Effect of prednisolone on cell-mediated cytotoxicity in vitro. Demonstration of a short sensitive induction phase. The effect of prednisolone on the kinetics of killing of Detroit-6 cells by rat lymphocytes has been studied utilizing the release of 51Cr as a measure of target cell death. The results show that in both killing by allergized lymphocytes, and killing of antibody coated target cells by normal lymphocytes, there is a short (less than 15 min) prednisolone-sensitive induction phase. Prednisolone has no effect on the reaction after this phase. The inhibition of induction by prednisolone appears to have two mechanisms. The first occurs rapidly following the addition of the drug to the cells, and must involve a primary action of prednisolone. Washing the cells free of prednisolone allows initiation, and killing can proceed almost normally, but if these washed cells are preincubated before mixing with target cells, then a secondary inhibition of induction develops progressively.


Inhibition of xenogeneic cell-mediated cytotoxicity in the rat by antiglobulin sera. Differences can be demonstrated between the lysis of xenogeneic target cells by lymphocytes of injected rats, which is inhibited by antiglobulin serum, and the lysis of antibody-coated xenogeneic target cells by normal rat lymphoid cells, which is much less readily inhibited. This difference is demonstrated by the dilution of antiglobulin which is effective, and by the fact that inhibition of lysis produced by allergic lymphocytes can be shown if the lymphocytes are treated with antiglobulin and then washed. Differences can also be shown in the time course of inhibition, since to be effective antiglobulin must be present at the time of mixing normal lymphocytes and antibody-coated target cells, whereas addition of antiglobulin to allergized lymphocytes 4 h ater mixing with target cells still produces significant inhibition. These results are compatible with the hypothesis that allergic lymphocytes have immunoglobulin on their surfaces and kill by a different mechanism from the lymphoid cells which lyse antibody-coated target cells.


Quantity and avidity of antibodies against birch pollen in atopic patients during hyposensitization. A preliminary study. The degree and strength of the binding of radioactively labelled allergen by antibodies in the sera of birch pollen-sensitive individuals was studied during the course of hyposensitization with alun-precipitated aqueous-pyridine extracted birch pollen antigens using the ammonium-sulphate precipitation technique originally described by FARR. The allergen binding was measured before and after absorption of the sera with anti-human IgE antibodies conjugated to Sepharose. It was noted that IgE antibodies of low avidity caused clinical sensitivity as well as IgE antibodies of higher avidity. The nasal sensitivity to birch pollen allergen of six of the seven patients studied significantly decreased by the treatment without any quite uniform change of serum-binding capacity for the allergen. Thus the clinical improvement was accompanied either by disappearance of the specific IgE antibodies, concomitant with formation of antigen-binding non-IgE antibodies, or by increased formation of IgE antibodies with very slight contribution by non-IgE antibodies to the totally increased antigen-binding efficiency. It is felt that the serological antibody changes may not  reflect the most relevant immunological events during successful hyposensitization therapy.


Nevus lipomatosus cutaneous superficialis. Nevus lipomatosus cutaneus superficialis (Hoffman-Zurhelle) is a distinct clinical entity. A case is reported in which the lesions were large, appeared early in childhood and were linear in distribution along the natal cleft.


Quantitative guidelines for exotropia surgery. The effect of numerous preoperative variables on the amount of surgical correction attained was assessed in a population of intermittent exotropic patients; 54 had bilateral recession surgery, 48 had recess resect surgery. By appropriate multivariate statistical analyses, about 95 per cent of the variance in results of surgery (expressed as change in deviation from preoperative to the postoperative time in prism diopters per millimeter of surgical correction) could be accounted for. A workable scheme for utilizing this data base to guide future surgery is presented in the form of quantitative formulae. In addition to this empirical derivation, insights are provided into the mechanics of ocular muscle operations and the maturation of the eye as it affects strabismus sergery. Expansion of this approach to a wider ranger of cases and to additional types of cases should result in a greater descriptive and surgical accuracy from strabismus surgery.


Observation of protein diffusivity in intact human and bovine lenses with application to cataract. Using the technique of optical mixing spectroscopy, we have observed the Brownian movement and measured the diffusivity of proteins within whole, intact human and bovine lenses. The magnitude and the temperature dependence of the protein diffusivity in bovine and normal human lenses implies that cold cataract is the result of a first-order phase separation of the protein-water mixture in the lens. The magnitude of the diffusivity of proteins within cataractous human lenses indicates the presence of large aggregates of proteins.


Ciliary ganglion stimulation. II. Neurogenic, intraocular pathway for excitatory effects on aqueous humor production and outflow. Data obtained suggest that preganglionic stimulation of the ciliary ganglion produces an increase of aqueous humor formation and of facility of outflow "C" through the following neurogenic pathway: (1) the preganglionic fibers synapse in the ciliary ganglion as evidenced by depression of the response with nicotine applied topically to the ganglion. (2) The impulse proceeds to the equivalent of an intraocular interneuron which can be blocked by low concentrations of atropine and has been previously identified as being an E-2 receptor site. (3) From the interneuron, activity is ultimately exerted without further synapse on alpha-adrenergic receptors through the release of norepinephrine from the neuronal terminals. The adrenergic mechanism of action is supported by the inhibition of the responses by phenoxybenzamine, bretylium, and guanethidine. Constriction of efferent ciliary process blood vessels by neuron-released norepinephrine seems to be the end effect responsible for the increased production of aqueous humor. The site of the end response to increase "C" is unclear.


Optic nerve circulation and ocular pressure: contribution of central retinal artery and short posterior ciliary arteries and the effect on oxygen tension. Blood-flow rate in the optic nerve of the rhesus monkey 4 mm. behind the globe monitored by the heated thermocouple and tissue p02 measurement is found to be influenced by ocular pressure level. Ligation of central retinal artery reduced flow rate to 79 per cent of normal but did not influence the effect of IOP on blood-flow rate. Ligation of short posterior ciliary arteries reduced blood-flow rate to 21 per cent of normal and virtually eliminated the IOP effect. Raising IOP to above systolic arterial pressure level reduced blood-flow rate to 17 per cent of normal. At IOP levels greater than 50 mm. Hg, the reduction in blood-flow rate and in Po becomes marked and may be sufficient to produce primary lesions at this site.


A spectrophotometric method for quantitative determination of lysozyme in human tears: description and evaluation of the method and screening of 60 healthy subjects. A spectrophotometric micromethod for lysozyme determination in tears is described, which enables the estimation of very low concentrations of lysozyme in individual tear samples, and which can be performed rapidly. The method is based on collecting the tears by a microcapillary tube and diluting them in a special manner which increases the volume of the tear sample, thus making possible analysis of other tear constituents in addition to lysozyme. Lysozyme activity in tears is determined by reduction of optical density (OD) of Micrococcus lysodeikticus suspension. The sensitivity of the method was determined on the basis of repetitive readings. The level of lysozyme in tears of 60 healthy people was determined by this method and found to be 6.1 mg. per milliliter hen egg lysozyme (HEL) with standard deviation of 1.57 mg. per milliliter HEL or 1.5 mg. per milliliter human tear lysozyme (HTL) with standard deviation of 0.39 HTL. Lysozyme level in tears of both eyes of each individual is equal, and any difference observed between the two eyes is due to the variability of the method.


Full-thickness eye wall biopsy. I. An experimental approach to the tissue diagnosis and study of choroidal and retinal lesions. A surgical approach to full-thickness eye wall biopsy is proposed as a method that may be applied to poorly understood diseases of the retina and choroid. An eye basket is sutured to the eye for stabilization, and two trephines mark an area to which diathermy is applied until penetration is achieved. The specimen is removed with fine forceps and scissors. A scleral homograft closes the defect. In ten rabbits, no eyes were lost and all ten retinas were intact. All biopsy specimens were suitable for histologic study.


Excitation and emission spectra of fluorescein dye in the human ocular fundus. The excitation and emission spectra of fluorescein dye were determined during angiography from different sites in the human ocular fundus. All spectra were markedly shifted toward longer wavelengths relative to the spectra of fluorescein in aqueous solution. This effect is most pronounced for the macular area; however, it decreases for the choroidal background and even more for the retinal vessels. The results are relevant to the selection of optical filter combinations for fluorescein angiography.


Localization of radioactive lead in ocular and skin melanoma. The ability of radioactive lead to localize melanomas was studied. The Greene melanoma in the Syrian Golden hamster served as a model for both skin and ocular melanoma. The affinity of heavy metals for neoplasms has been studied but previous reports have been inconsistent as to tumor specificity. For this investigation the radioactive lead (203-Pb,) was studied as the chemical complex 203-Pb-Tris. Significant tumor:nontumor ratios were found in ocular melanoma and the concentration in the lens was minimal. The ratio of per cent uptake per gram of tumor: per cent uptake per gram in control tissue with skin melanoma was 9.4 at 24 hours and for the eye melanoma the ratio was 26.3 at 24 hours. The affinity of 203-Pb-Tris for melanomas appears to be as promising as other compounds presently being evaluated for ocular scintigraphy, namely, labeled quinoline analogs. Therefore, further preclinical evaluation is warranted.


Vascular alterations in canine histiocytic ulcerative colitis. The large intestines of eight boxer dogs with canine histiocytic ulcerative colitis (CHUC) and 10 normal dogs were studied by in vivo angiography and postmortem microangiography.  The vascular abnormalities were correlated with the gross and histologic pathology found at necropsy.  The angiographic abnormalities were variable, non-specific and were gross indicators of disease.  Intestinal segments with mild, focal inflammatory lesions appeared normal, while diseased segments with more extensive inflammatory change exhibited variable vascular dilatation and hypervascularity.  Microangiograms of bowel specimens with an early mucosal lesion were normal.  With increased disease severity, there was microvascular dilatation with attenuation of mucosal arterioles.  Areas with focal or confluent ulcerations demonstrated complete disruption of the mucosal microvascular bed and replacement with the chaotic tangle of ectatic vessels, characteristic of granulation tissue.  Anatomic arteriovenous shunts were not observed.


Addition of calcium or other cations and of oxygen to ionic and non-ionic contrast media.  Effects on cardiac function during coronary arteriography. Metrizamide is a new non-ionic water soluble contrast agent.  Isolated rabbit hearts were perfused with solutions of 1) metrizamide, 2) metrizamide with plasma equivalent amounts of cations, 3) oxygenated metrizamide, 4) oxygenated metrizamide with cations, 5) diatrizoate.  Solutions of 1) metrizamide, 2) metrizamide with plasmaequivalent amounts of cations, 3) metrizamide with calcium ions, 4) metrizoate (ionic medium) with calcium ions, metrizoate with 5) low and 6) high sodium content and 7) diatrizoate were injected into the left coronary artery of dog hearts in vivo.  Maximal change of myocardial contractile force was measured with a strain gauge arch.  Changes in aortic blood pressures were also recorded.  In both sets of experiments metrizamede affected these parameters less than the ionic contrast media.  The addition of calcium ions to both ionic and non-ionic media reduced the adverse effects on the observed cardiac funcitons, while simultaneous addition of plasma equivalent amounts of four cations as metrizoate salts had no beneficial effects.  Sodium ions had in high concentration deleterious effects on cardiac performance.  Oxygen saturation of the contrast medium had no observable effect.  The adverse effects on cardiac mechanical function of sodium ions and possibly other cations contained in a contrast medium solution might be counterbalanced by the addition of calcium ions to the solution.


The effect of metoclopramide on the contraction of the human gallbladder. In a double blind study 45 patients were given either an i.v. injection of 20 mg Primperan (20 mg metoclopramide, Lundbeck, n = 15), 20 mg Metopram (20 mg metoclopramide, Leiras, n = 15) or a corresponding amount of physiological saline (n = 15) and the effect of metoclopramide on the human gallbladder was studied in x-ray examination of gallbladder.  The gallstones do not appear to be a contraindication for the clinical use of metoclopramide as an antiemetic drug.  No contraction of the gallbladder was demonstrated, even though metoclopramide has been shown to contact intestinal smooth muscle.  Primperan caused more side effects than Metopram.  Sedation seems to be the most common side effect of metoclopramide.


The role of calcium and fluoride in osteoporosis in rhesus monkeys. Twenty-two female Rhesus monkeys were fed purified diets varying in calcium and fluoride content for five years and studied, using radiographic, photon absorptiometric and histologic techniques.  The results suggested that: 1) the addition of fluoride (50 ppm) to a diet containing 1 per cent calcium resulted in a reduction in bone growth rate and resorption, without affecting bone size or density nor resulting in fluorosis; 2) a diet containing 0.15 per cent calcium resulted in osteoporosis due to an increase in bone resorption; and 3) fluoride added to a similar low calcium diet prevented osteroporosis by reducing bone growth rate and resorption resulting in bones with normal density, but at the same time fluoride interfered with mineralization of osteoid leading to osteomalacia.


Ultrasonic pulmonary Densitometry: preliminary studies. The feasibility of using A-mode ultrasound to measure lung density changes was tested in two studies.  (A) Wet sponges were used as experimental analogs of the lung.  The sponges were weighed.  A-mode recordings were obtained by placing the transducer face against a sheet of film in contact with each sponge.  Ultrasound penetration increased directly with increasing water content.  The range of densities studied corresponds with that which occurs in normal and edematous human lungs.  In a second study (B), the depth of ultrasound penetration into 3 postmortem human lungs was measured at increasing levels of inflation by positive intrabronchial pressure.  Ultrasound penetration decreased approximately logarithmically with increasing inflation pressure.  These relationships indicate a potential application of ultrasound to pulmonary densitometry.  This could provide a noninvasive means for clinical estimation of changes in lung water, without the use of ionizing radiation.


The point of diminishing returns in nutrition education through home visits by aides: an evaluation of EFNEP. This three-year evaluation of field work with poor, rural homemakers by nutrition aides employed by the Expanded Food and Nutrition Education Program (EFNEP) of the Maryland Cooperative Extension Service is based on successive annual interviews with 93 homemakers and a control group of 58 designated friends. The results suggest various points of diminishing returns beyond which behavioral and attitudinal changes brought about by the specific educational strategies are too small to justify continued visits to a homemaker. To sustain cost-effective home visits after the first year, more emphasis must be placed on reinforcement of first-year gains, and on expanding the scope of nutrition education to include more health education of other kinds.


[Surgical preparation planning of hemodialysis candidates]. An early beginning of chronic hemodialysis is postulated to prevent dangerous uremic complications. Subcutaneous arteriovenous fistulas or autologous saphenous vein grafts in cases where multiple attempts to create a sufficiently functioning arteriovenous fistula have failed turned out to be the best procedures to obtain a suitable access to the blood vessels. The problems arising on a total of 57 patients to get an adequate blood flow by the time of first hemodialysis are discussed.


[Observations on surgical technic in inguinal femoral hernia according to McVay]. The technique of the operation first published by MCVAY in 1949 for the treatment of the inguinal and fermoral hernia is briefly described and its advantages, compared with the method of BASSINI, are discussed. The essential factor consists in the use of the fascia transversa abdominis which is sewn on to the ligament of Cooper instead of attaching the musculus obliquus externus to the ligamentum inguinale. The operation demands an accurate knowledge of all the anatomical structures concerned and a strict observance of the technique described.


[Complications of surgery in cirrhosis]. Extraabdominal operations are relatively well tolerated by the cirrhotic patient. However abdominal and thoracic surgery are followed by a very high morbidity and a mortality reaching 50% in these patients. Aggravating factors such as a decompensated cirrhosis and an alcoholic or viral hepatitis bear a catastrophic prognosis. The decision to perform surgery should as much as possible imply a knowledge of the histological nature of the cirrhosis and an intensive pre-operative preparation of the patient particularly in the respiratory and cardiac field.


[Surgery of aortic valvulopathies].

[Surgery of aortic valvulopathies]. 75 patients were operated for isolated aortic congenital or acquired valvulopathies (46 men, 25 women and 4 children). 8 patients were reoperated because of functional defects of the artificial valve or paravalvular dehiscence. 3 children from 3 to 10 years of age underwent aortic valvular commissurotomy. The other patients had aortic valve replacement by an artificial valve. Two types of valves were used. In the beginning, we employed the Starr-Edwards valves, models 1200, 2300, 2310 and 2320. Since July 1971, we are using the Björk-Shiley valve. Less pressure gradient across the valve and less hemolysis with Björk-Shiley valve are two important factors in favoring its use. Our hospital mortality has been 5.3% and late mortality also 5.3%. Clinical improvement is observed among 80% of patients in follow-up controls.


Barking dogs as an environmental problem. The levels of noise from barking dogs in and near representative veterinary hospitals were measured and evaluated to determine their effects on practicing veterinarians, their staffs, clients, and neighbors. Special design criteria to minimize noise levels within the hospitals and dog confinement areas, and to prevent noise travel to other parts of the establishments and to surrounding neighborhoods, were an important element of the study.


Evaluation of four techniques of cervical spinal fixation in dogs. Four surgical techniques for immobilizing unstable cervical vertebrae were evaluated. These techniques included: (1) placing screws bilaterally through the articular processes, (2) placing wires bilaterally through the articular processes, (3) placing a bone screw through vertebral bodies, and (4) placing a bone plate on the ventral surface of adjacent vertebral bodies. Each technique was found to have certain advantages and disadvantages.


Idiopathic hyperlipoproteinemia in dogs. Six dogs with hyperlipoproteinemia of undetermined cause had increased serum concentrations of lower density lipoprotein classes, as detected by lipid measurements and lipoprotein electrophoresis. Five of the dogs were Miniature Schnauzers and 1 was of mixed breeding. Signs of disease included abdominal distress (2 dogs), abdominal distress and seizures (2 dogs), and weizures (1 dog). One dog was clinically normal. Feeding of a low-fat diet resulted in alterations of lipoprotein distribution and serum lipid content. In 2 dogs, intravenous (IV) administration of heparin caused shifing of the lipoprotein electrophoretic pattern, indicating activated lipoprotein lipase. These clinical and laboratory findings suggested a syndrome caused by an inherited defect in lipid metabolism.


Hyperammonemia due to a urea cycle enzyme deficiency in two dogs. Hyperammonemia in 2 dogs was associated with a deficiency of arginosuccinate synthetase, one of the enzymes of the urea cycle. The usual criteria for evaluation of hepatic function were normal.


Rectal and vaginal constriction in Jersey cattle. Three Jersey herds had a total of 14 cows with constriction of the anorectal area and of the vagina. Maternal and paternal lines of all affected cows were traced to a common ancestor.


Survival of certain pathogenic organisms in swine lagoon effluent. Six pigs from a closed herd with no evidence or history of salmonellosis or swine dysentery were fed effluent from an anaerobic lagoon on a farm where salmonellosis and swine dysentery were enzootic. Salmonella saint-paul was isolated from the effluent and fromthe feces and certain tissues of the pigs. Clinical signs typical of swine dysentery and enteric shedding of large numbers of spirochetes with the characteristics of Treponema hyodysenteriae were noted in 5 of the 6 pigs.


The effect of starvation and refeeding on cell population kinetics in the rat small bowel mucosa. Male rats were starved for a period of 96 hours. Measurements of crypt cell population showed a small reduction during starvation. The growth fraction remained constant, but the total number of proliferating cells per crypt fell as a consequence of the reduction in crypt population. Both labelling and mitotic indices fell throughout the starvation period. The cell cycle time (Tc), measured by a stathmokinetic technique using vincristine, was increased from 10-4 hours in control rats to 14-7 hours after 96 hours' starvation. Upon refeeding, the proliferative indices were observed to rise. After a small initial fluctuation, the growth fraction remained constant. The crypt population remained substantially unchanged. Sixteen hours after refeeding, the cell cycle time was reduced to 6-5 hours. The hypoproliferative response to starvation is mediated solely by an increase in cell cycle time, and the response to refeeding is interpreted in terms of a reduction in Tc. Changes in the size of the proliferating population are considered not to play an important role in either response, although it is not possible to exclude entirely the presence of resting cells in the proliferative compartment itself.


Observations on the submucous plexus and mucosal arteries of the dog's stomach and first part of the duodenum. Arteriolar patterns of the submucous plexus were studied in all areas of the dog's stomach and in the first inch of the duodenum. There appeared to be no poverty of plexus, although in some cases the vessels were somewhat smaller in the pyloric part of the lesser curvature than elsewhere. Mucosal arteries arose from the plexus, and none appeared to have an extramural origin. In man, on the other hand, there is a poverty of the submucous plexus in the 'ulcer region', i.e. in the incisural region of the lesser curvature and in the first inch of the duodenum, associated in some cases with mucosal end arteries of extramural origin. The absence of these features in the dog, which does not suffer from spontaneous chronic ulceration, lends further support to the view that they play a role in the aetiology of the disease in man.


Studies of oogenesis and follicular development in the golden hamster. 2. Initiation and control of meiosis in vitro. The onset of meiotic prophase in the hamster occurs after birth and therefore it is possible to obtain ovaries which are at a relatively early stage of differentiation. Ovaries were maintained in vitro where the factors which might influence the onset of meiotic prophase could be studied in isolation. It was found that if ovaries were explanted prior to day 15 p.c. meiotic prophase began, but was subsequently blocked at the leptotene stage: the remaining oogonia and the oocytes at leptotene degenerated around day 5 p.p. By day 7 p.p. the few remaining oocytes were found at an abnormal stage which resembled leptotene. The addition of gonadotrophic hormones or maternal serum to the culture medium had no effect on the initiation of meiosis, neither had culture with the intact oviduct. By contrast, removal of the ovaries on or after the 15th day of gestation permitted meiotic prophase to proceed normally and oocytes at the diplotene stage were observed in the explants 8 days later. Culture of ovaries removed before day 15 p.c. resulted in abnormal development of the ovarian stroma: only when ovaries were explanted on day 15 or after was the development of 'nests' of oocytes normal. The evidence for endocrine control of oogenesis is discussed in the light of work on intersex animals and artificial chimaeras. These studies strongly suggest that oogonia enter meiosis spontaneously at the time which is specific for the species.


Studies of oogenesis and follicular development in the golden hamster. 3. The initiation of follicular growth in vitro. Ovaries derived from hamsters on day 5 p.p. were maintained in organ culture for 15 days. It was found that the process of follicular growth was severely retarded in organ cultures devoid of gonadotrophic hormones. The addition of FSH and LH resulted in a partial improvement in follicular development, a result which supports the view that gonadotrophic hormones are important in the early development of the ovary.


Observations on the three-dimensional structure of the nucleolar channel system of the human endometrial glandular cell. Nucleolar channel systems from human endometrial glandular cells have been subjected to three-dimensional analysis using a goniometer stage. The results are compatible with a secondary helical conformation of the constituent tubules and this idea has been incorporated into an improved model of the channel system.


Abnormalities in Schwann cell sheaths in spinal nerve roots of dystrophic mice. Dorsal and ventral spinal roots at cervical, thoracic, lumbar and sacral levels in dystrophic, dy/dy, mice of both 129/ReJ and C57Bl/6J phenotypes showed a complete lack of Schwann cell sheaths of any sort around the majority of their nerve fibres. This condition, termed amyelination, is more extensive (up to 1-5 cm in length) in the longer lumbar and sacral roots than in the shorter roots or in the proximal regions of the sciatic nerve which are also affected to some extent. Amyelination does not appear to be a consequence of myelin or Schwann cell degeneration, as debris is uncommon. Heterozygous carriers are not affected in any obvious way. Myelinated fibres, with Schwann cells of peripheral origin, occur immediately adjacent to the spinal cord in both dorsal and ventral roots, while in dorsal roots unmyelinated fibres also occur, as in normal animals. Amyelinated fibres begin to appear a few internodal lengths away from the cord and are present until near, or within, the dorsal root ganglion, where they become myelinated again. The portion of an axon which has no myelin begins at a normal appearing paranodal region (termed a half node of Ranvier) at the end of a myelin internode. Resumption of myelination likewise begins at a half node. A few myelinated axons may be seen in any given cross section of a root, but as a rule a given myelinated fibre does not remain myelinated throughout the whole length of the root. It is suggested that the nerve lesions develop where the nerves are lengthening rapidly as the animal grows and changes its shape. How these nerve changes release to those in muscle is conjectural.


The development of nephrocalcinosis in the rat following injections of neutral sodium phosphate. The development of nephrocalcinosis in the rat following intraperitoneal injections of various concentrations of neutral sodium phosphate (pH 7-4) was studied using histology, histochemistry, electron microscopy and quantitative techniques. Daily injections of 0-5 M phosphate consistently produced nephrocalcinosis after 6 days or more. Calcium deposits were at first confined to the basement membranes of proximal tubules; but a longer course of injections, up to 10 days, resulted in additional basement membrane calcification in the outer cortes, and outer medulla, together with intra-luminal casts, often calcified, in the outer medulla and papilla. Calcification was not found in other organs such as liver, lung, heart or aorta. Results from quantitative estimations of total kidney calcium and phosphorus suggested that it was the calcium content which was important to the initiation of nephrocalcinosis. Ultrastructural changes, suggestive of degeneration or alteration in function, were found in mitochondria of proximal tubules in experimental animals before the onset of histologically evident nephrocalcinosis. Later changes, especially to the basal part of proximal tubular cells and their basal laminae, were thought to be consequent upon the mitochondrial changes. It is suggested that the initial renal damage was caused both directly, by a toxic effect of the phosphate load on the kidney and, indirectly, by stimulation of the parathyroid glands as a result of the hypocalcaemia and hyperphosphataemia which followed an injection of phosphate. Daily doses of 1 M phosphate for 3 days produced a type of nephrocalcinosis which was more typical of that reported by previous investigators, who used high doses of phosphate. Twice daily injections of 0-25 M phosphate for 6 days did not induce nephrocalcinosis, whereas 0-375 M phosphate given twice daily for 6 days produced only minimal calcium deposits compared with animals given 0-5 M phosphate once daily for the same period. This may have important clinical implications, since phosphate has been used to control hypercalcaemia of various etiologies.


On the relationship between tetracycline and the incremental lines in dentine. Ground and decalcified sections of human, goat and pig teeth were examined using polarized and ultraviolet fluorescence microscopy, microradiography and electron microscopy. The experimental animals were given doses of tetracycline within the range 3-150 mg/kg. After the low doses there was no evidence of any disturbance of mineralization or of structural organization in either the goat or the pig. After the higher doses, however, the tetracycline lines usually corresponded with a disturbance of structural organization and often with a disturbance of mineralization as well. In the human cases, the tetracycline lines sometimes corresponded with a disturbance of mineralization or of structural organization. However, our evidence suggests that the disturbances in the structure or mineralization of the dentine in the human subjects were not caused by the tetracycline. It was concluded that, provided the dose is kept low (3-31 mg/kg) tetracycline can be used as a reliable non-toxic marker in growth studies and is also used in the study of mineral deposition.


On the configuration of incremental lines in human dentine as revealed by tetracycline labelling. The pattern of tetracycline labelling in dentine was investigated in ground sections of human teeth under visible and ultraviolet light. The tetracycline lines presented different appearances near the enamel-junction region, near the dentine-cementum junction, in the mantle dentine, and in the circumpulpal dentine, depending on whether the mineralization front was linear, globular or linear-globular.


A quantitative electron microscopic study of myelination in the anterior limb of the anterior commissure of the mouse brain. An electron microscopic study of myelination was carried out in the anterior limb of the anterior commissure of the mouse brain. The total number of axons increased from 48 700 at 17 days post-conception to 286 500 at 11 days postnatum. The first evidence of myelination was the presence of a few promyelin fibres at 8 days postnatum. Myelinated axons were first found at 11 days postnatum. The most rapid increase in myelinated fibres occurred between 17 and 21 days postnatum, but myelination continued to increase even after 45 days postnatum. There was no change in mean diameter (0-27 mum) of unmyelinated axons after 18 days post-conception. The mean diameter of myelinated axons (0-53 mum) also showed no variation with age. The modal diameter of myelinated axons lay between 0-4 and 0-6 mum. Small fibres (0-2-0-3 mum) myelinated around 32-35 days postnatum. The greatest increase in large myelinated axons (larger than or equal to 0-8 mum) occurred after 25 days postnatum. At all ages sheaths with outer and inner tongues in the same quadrant predominated and by 240 days postnatum 80% of sheaths showed this configuration.


An ultrastructural study of sinuatrial node cells in the embryonic rat heart. Sinuatrial nodal tissue, obtained from rat embryos of 15, 16 and 17 days, was examined with the electron microscope. Embryonic nodal cells were generally similar to adult cells except that (1) they showed thick prolongations of the cytoplasm which insinuated themselves between neighbouring cells; (2) they possessed osmiophilic granules with a predeliction for the region of the Golgi complex; (3) they exhibited a lesser and variable degree of pinocytosis.


The distribution and function of lysosomes in condylar cartilage. Using electron microscopic and histochemical methods it was possible to demonstrate in condylar cartilage the presence of acid phosphatase and aryl sulphatase in lysosome-like bodies of the cartilage cells, confirming that they are lysosomes. Lysosome-like bodies were also present in the extracellular matrix, but they reacted for acid phosphatase only. Lysosomes extruded by the cells may well provide a means whereby lysosomal enzymes are enabled to take part in the preliminaries to matrix calcification. The large numbers of lysosomes in the hypertrophic chondrocytes, however, are probably more concerned in bringing about autolysis of the cells than in promoting calcification of the matrix.


Pseudoeosinophilic leucocyte response to denuding the rabbit cornea. After scraping the epithelium from the rabbit's cornea, pseudoeosinophilic leucocytes appeared in the limbic area within one hour and began to advance, presumably by means of pseudopodia, into the anterior corneal stroma. The cytoplasmic granules of these cells were intensely stained by eosin and by the Undritz peroxidase method during the first hour, but were not stained by the PAS method until the eighteenth hour. Electron microscopy failed to show crystalloids in the granules. The cellular changes were followed until the fourth day, by which time most of the cells had disappeared by fragmentation, karyorrhexis and lysis.


A systematic approach to the quantitative description of musculo-skeletal geometry. 1. A systematized computer technique of centroid analysis has been developed to evaluate the precise geometric relationship between a muscle and a bone and it has been applied to the abductor mechanism of the human hip joint. 2. The validity of the traditional use of straight lines for displaying the line of action of a muscle is open to serious question, although in the case of the gluteus medius the straight line simplification is not unmeasurable. 3. The determination of the precise interactions of muscles and bones is of major importance in the consideration of various orthopaedic procedures.


A light and electron microscopic study of proliferation and maturation of fibrous astrocytes in the optic nerve of the human embryo. Optic nerves from perfusion-fixed human embryos of 28,50,75,105,120 and 165 mm crown-rump length were examined in the electron microscope. The number of glial cells per section was found to increase steadily from 10 weeks post-conception to 18 weeks and a close correlation (r = 0.92) was found between the percentage vascularity and the glial population. Mitotic figures were present in all optic nerves examined. From 14 weeks onwards all glial cells, except pericytes, were found to be fibrous astrocytes. The human fibrous astrocyte appears to pass through the following stages of development: (1) Astrocytic precursors (dark glioblasts) have a dense cytoplasmic matrix with few organelles, although a single cilium is frequently present.(2) Concomitant with the increase in vascularization of the optic nerve found between 12 and 14 weeks glycogen granules increase in the cytoplasm of astrocytic precursors, followed by microfibrils, which appear first in the processes and later extend into the perikaryon. (3) With the appearance of glycogen granules the cytoplasmic organelles, particularly mitochondria, increase in amount and the cytoplasmic matrix gradually becomes less dense. (4) With increasing age fewer organelles are found in astrocytic processes, which become thinner and densely packed with microfibrils.


The development of the olfactory mucosa in the mouse: light microscopy. The development of the olfactory and vomeronasal epithelia of the mouse has been investigated from the 9th day of gestation until shortly after birth. On the 10th day axons emerge from the base of the olfactory epithelium to reach the olfactory bulb primordia on the 11th day, at which time the olfactory dendrites first appear. On the 13th day a distinction between the elongate nuclei of the embryonic stem cells and the rounded nuclei of the differentiating receptors is visible. A basal layer of stem cells remains mitotically active from the 13th day of gestation onwards, and after the 15th day the majority of mitoses occur in this layer. It is suggested that from the 15th day of gestation onwards the nuclei situated most apically become those of the supporting cells. The glands of Bowman are first visible on the 17th day of gestation. The diverticulum of the vomeronasal organ begins to form on the 11th day and the development of its sensory epithelium resembles that of the olfactory organ except for the absence of basally situated stem cell nuclei in the later stages of the vomeronasal organ.


Chick vincula: elastic structures with a check-rein mechanism. From their mode of attachment and their elastic composition, it is clear that the vincula of the chick serve other functions besides that of carrying blood vessels to the digital flexor tendons within their synovial sheaths. Evidence is presented in support of the argument that elastic fibres bear the brunt of rapidly applied tensile forces and that the interweaving collagen fibres only become taut when the vincula are stretched to the limit and about to tear. Our hypothesis is that the collagen serves as a check-rein mechanism in an otherwise elastic structure.


Cholinesterase activity in the hypoglossal nucleus of the rat and the changes produced by axotomy: a light and electron microscopic study. Within the hypoglossal nucleus large amounts of acetylcholinesterase (AChE) activity are present in all the neurons, whereas intracellular butyrylcholinesterase (BuChE) activity occurs only within a ventro-caudally situated cluster of cells. AChE activity within the neurons occurs mainly in the cisternae of the granular endoplasmic reticulum but there is some in the intermembranous space of the nuclear envelope and in the Golgi complexes. In the neuropil, reaction product is seen along some axonal and synaptic membranes. The distribution of BuChE in the ventro-caudal cells is identical with that of AChE except that BuChE activity is absent from the neuropil. The level of intraneuronal AChE activity falls rapidly during the first few days after axotomy. The fall is due partly to a dissolution and peripheral migration of the E.R. but also to a decrease in AChE content of the E.R. that remains. Return of staining begins in the 4th week and continues as the E.R. reassembles. Staining in the neuropil falls more slowly, but recovers less completely. The ventro-caudal group of cells shows the same kinds of change, but more dramatically. BuChE activity returns only erratically and never completely. The similarity in normal distribution, and in response to axotomy, of the two cholinesterases suggests that their functions are related.


A study of mitotic activity and the diurnal variation of the epithelial cells in wounded rectal mucous membrane. Excision ulcers of the rectal mucous membrane were made in two groups of rats. One group was wounded at 09.00 hours and the second group at 21.00 hours. Mitotic counts were carried out in the glandular epithelium at the ulcer edges at 2 hour intervals over a period of 24 hours. Mitotic activity increased in 2-4 hours and thereafter showed a peak-and-trough pattern. The wounded rectal epithelial cells exhibited a diurnal variation with a peak of activity during the day and a low period of activity at night. It would seem unlikely that the adrenaline-chalone complex acts on the rectal epithelium, as this would entail maximal mitotic activity during periods of rest, when the circulating levels of adrenaline in the rat are at their lowest. The experiments clearly showed that the diurnal variation was not abolished by wounding. The increased mitotic activity occurred in the epithelial cells in the lower and mid thirds of the colonic glands; dividing cells were rarely seen in the top twenty cells or so of the glands, or in the surface epithelium. Mitotic activity was often lower in the first one or two glands at the immediate wound edge, which is difficult to explain by present theories of mitotic control.


Increase in fibre numbers of the rat pterygoid muscles during postnatal growth. The total numbers of fibres in transverse histological sections of the pterygoid muscles of Lister rats of various ages were counted on enlarged photomicrographic prints. The number in the medial pterygoid of the male doubled between birth and six weeks. This was followed by a decrease of rather more than 10 percent in the numbers between six weeks and the adult stage in both males and females. The number of fibres in the lateral pterygoid of the male increased by about 45 percent between birth and the adult stage. There were about 15 percent fewer fibres in the medial pterygoid of the adult female than in the male; no such sex difference occurred in the lateral pterygoid. Early precursors of muscle fibres were seen in histological sections of these muscles in the newborn, confirming new fibre formation after birth. Such precursors gradually disappeared, starting with the most primitive, so that by the age of four weeks the muscles had a mature appearance.


Direct association of messenger RNA with microsomal membranes in human diploid fibroblasts. Messenger RNA (mRNA) of membrane-bound polysomes in a membrane fraction of WI-38 cells remains associated with the microsomal membranes even after ribosomes and their nascent polypeptide chains are removed by using puromycin in a high salt buffer or by disassembling the ribosomes in a medium of high ionic strength lacking magnesium. mRNA either was specifically labeled in the presence of actinomycin D, or it was recognized by virtue of its affinity for oligo-dT. Poly A segments in bound mRNAs have an electrophoretic mobility in acrylamide gels which is characteristic of cytoplasmic mRNAs and corresponds to 150-200 adenyl residues. Extensive RNase treatment did not lead to release of the poly A segments of membrane-associated mRNA molecules either from an intact membrane fraction or from a membrane fraction previously stripped of ribosomes. On the other hand, RNase treatment led to the release and digestion of the nonpoly A segments of the mRNA molecules, indicating that the site of attachment of mRNA to the ER membranes is located near or at the 3' end of the molecule which contains the poly A. A direct association of mRNAs and endoplasmic reticulum membranes is considered in a modelto explain the assembly of bound polysomes and protein synthesis in a membrane-associated apparatus.


The mechanism of formation of inhibitor-induced ribosome helices in Entamoeba invadens. Helices andaggregates of helices (chromatoid bodies) composed of ribosomelike particles appear in cysts and slow-growing trophozoites of Entamoeba invadens. We found that similar helix aggregates were formed abundantly in actively growing E. invadens trophozoites treated with a variety of direct or indirect inhibitors of protein synthesis. The inhibitor-induced helices appeared cytochemically and ultrastructurally identical to those seen in cysts. Numerous single helices and small arrays occurred randomly distributed throughout the trophozoite cytoplasm within 15 min after treatment with NaF, which rapidly and completely stopped all nucleic acid and protein synthesis. Cycloheximide (CH), which inhibited protein synthesis as effectively a NaF, stimulated aggregate formation more slowly, and only after a delay of 30-60 min. CH temporarily blocked NaF-stimulated aggregated formation. Aggregation was slowest with actinomycin-D, which strongly inhibited RNA synthesis but depressed protein synthesis only slowly. These results suggested that release of ribosomes from mRNA was required for aggregation. Inhibition by CH was reversible, and aggregates disappeared from CH-treated amebas shortly after they were transferred to inhibitor-free frowth medium. There was no evidence that helices assembled about a structural organizer within the cell or that the process involved metabloc activity. It was concluded that the inhibitor-induced helices were composed of mature, normally functional ribosomes and that helix formation was a spontaneous and reversible consequence of the accumulation withing the cell of free monosomes (or subunits) which were prevented from binding to mRNA.


Comparision of the structure and function of polysomal and helical ribosomes from Entamoeba invadens. Some structural and functional properties of ribosomes from polysomes and from helix aggregates of Entamoeba invadens have been compared by sucrose gradient analysis and assays of in vitro protein synthesis. Actively growing trophozoites, lacking helices, presented normal polysome profiles in sucrose gradients. The single large ribosomal helix aggregate (chromoatoid body) of cysts diappeared as the cells were disrupted. Gradient profiles of cyst extracts contained predominantly large and small ribosome subunit peaks and no evidence of remaining helix fragments of mRNA-bound polysomes. Sequential profiles of trophozoites incubated with NaF or cycloheximide (which both stimulate ribosome aggregation, but at different rates) showed that polysome breakdown occurred before aggregates appeared and, again, that helices broke down to subunits in vitro. Radioactive ribosomes synthesized during vegetative growth were collected into helices during encystation. Subunits of these ribosomes cosedimented with comparable particles isolated from trophozoites. Ribosomes from both trophozoites and cysts were active in cell-free protein synthesis, although activity in cyst extracts required  the addition of trophozoite-soluble fraction. It was concluded that ribosomes from polysomes and helices in E. invadens were probably identical and that the ability to form helices was an intrinsic property of mature mRNA-free ribosomes of this organism.


Pressure-induced depolymerization of spindle microtubules. I. Changes in birefringence and spindle length. Changes in birefringence retardation (BR) and length of Chaetopterus meiotic metaphase-arrested spindles produced by increased hydrostatic pressure were observed with polarized-light microscopy using a newly developed optical pressure chamber. Increased pressure produced rapid, reversible decreases in spindle BR and length. Pressures of 3,500 psi or higher at 22 degrees C caused complete disappearance of spindle BR within 3 min. Up to 6,000 psi, the rates of both BR decay and spindle shortening increased progressively with increasing pressure. At 6,000 psi or above, the BR decreased rapidly but there was no evidence of spindle shortening. The general observations are consistent with results of earlier classical experiments on effects of pressure on mitosis, and with experiments that used colchicine or low temperature as microtubule-depolymerizing agents. The kinetics of spindle depolymerization and repolymerization showed two phases: an initial phase of rapid decreases or increase in half-spindle microtubule BR; and a second phase of nearly constant BR during which most of the spindle shortening or growth occurs. BR is assumed to be directly related to the number of microtubules in a spindle cross section. It is hypothesized that microtubules in the spindle have different stabilities depending on the attachment of nonattachment of their ends. This hypothesis is used to explain the two phases of spindle depolymerization and repolymerization as well as  several other observations.


An improved technique for the analysis of amino acids and related compounds on thin layers of cellulose. X. The characterization of some methionyl, phenylalanyl, tyrosyl and other peptides by thin-layer and ion-exchange chromatography. This paper is a continuation of previous work (Parts VI, VIII, and IX) designed to identify small peptides in biological fluids by a combination of ion-exchange and thin-layer chromatography. Several series of peptides, mainly dipeptides, with methionine, phenylalanine, tyrosine, aspartic acid, serine, or glutamic acid as the N-terminal amino acid, have been examined.


Gas-liquid chromatographic determination of theophylline in human plasma. A gas-liquid chromatographic method for the estimation of theophylline in human plasma is described. The method is based on the methylation of theophylline on-column and allows the determination of concentration of the drug down to the level of 1.0 mu-g/ml in plasma.


Quantitative thin-layer spectrodensitometric determination of the components of polyene macrolide antibiotice complexes. A direct spectrodensitometric method for quantitating the components of polyene macrolide complexes after separation by thin-layer chromatography is described. Resolution of the components of the candidin and candihexin complexes was good up to 2.5 and 10 mu-g/spot, respectively. The peak areas were linear with the amount spotted up to the same levels. Maximum peak areas for the components of the candidin and candihexin complexes were obtained using light wavelengths of 360 and 340 nm, respectively. Spotting errors rather than instrumental parameters were responsible for the variance of repeated determinations. Minimal relative standard deviation values were found at intermediate concentration levels in the linear range.


A method for the separation of plasma amino acids by ion-exchange chromatography combined with a semi-automatic computation of plasma amino acid concentrations. A method is described for combining the separation of plasma amino acids on a single column amino acid analyzer with semi-automatic computation of the plasma amino acid concentrations. The system used for the quantitation of the amino acids consists of an integrator with a teletype printer fitted with a puncher, and a table calculator with a punch reader and a converter. By using this system, the total time required for the calculation of the molar plasma concentration of 30 amino acids from one analytical run is less than 10 min.


Comparison of methods for aflatoxin analysis by high-pressure liquid chromatography. Reversed-phase columns packed with octadecyl and phenyl reversed phases did not provide adequate separation of aflatoxins. A peculiar adsorption column provided partial separation, i.e. B1 and B2 from G1 andG2, but not B1 from B2 nor G1 from G2. A microparticulate adsorption (7icro-A) column completely separated aflatoxins B1, B2, G1, and G2. Detection was more selective at 350 nm (or 365 nm) than at 254 nm. A Fluoro Monitor Model 1209 detector (Laboratory Data Control Corp.) was more sensitive for aflatoxins G1 and G2 than for B1 and B2. Aflatoxin B1 at the 30-ppb level in yellow corn was detected with the Micro-A column and the 350-nm photometer. The limit of detection was estimated at about 10 ppb.


[Fluorimetric determination of testosterone on Al2O3 by thin-layer chromatographic separation of the trimethylsilyl ether derivatives (author's transl)]. Small quantities (parts per 10-9) of testosterone were determined in the presence of large amounts of other steroids in urine samples obtained during pregnancy by subjecting their trimethylsilyl derivatives to spectrofluorimetry on alumina after purification by thin-layer chromatography on silica gel. The activity of the alumina and the fluorescence reactions are discussed.


Quantitative determination of cocaine and its metabolites benzoylecgonine and ecgonine by gas-liquid chromatography. A sensitive and reliable method was developed to determine quantitatively cocaine and its metabolites benzoylecgonine and ecgonine. The method involved the formation of fluoro derivatives which were separated on 3% and 5% OV-1 columns and detected in picomole quantities using an electron capture detector. Ecgonine and benzoylecgonine were derivatized with a mixture of hexafluoroisopropanol-heptafluorobutyric anhydride (1:2). Cocaine was first reduced by LiAlH4 and then acylated by pentafluoropropionic anhydride. Benzoylecgonine, but not ecgonine, could also be determined by reduction and subsequent acylation. This provided the basis for the determination of cocaine, benzoylecgonine and ecgonine from the same sample. Cocaine could be determined in urine and plasma by this method.


[Quantitative determinaton of glycerides by densitometry (author's transl)]. After determination of charring conditions and the measurement by densitometry of lipids separated by thin-layer chromatography, a statistical analysis was performed to determine the significance of the results. Calibration curves were studied and response factors calculated for some saturated and unsaturated triglycerides.


Kinetics of heroin deacetylation in aqueous alkaline solution and in human serum and whole blood. A kinetic study of heroin hydrolysis in alkaline aqueous solution at room temperature was conducted by a gas chromatographic method to measure the consecutive reactions of diacetylmorphine to monoacetylmorphine and of monoacetylmorphine to morphine. A first-order reaction was observed in both instances, and the rate for the deacetylation of heroin was greater than that of monoacetylmorphine. The rates of in vitro hydrolysis of diacetylmorphine in human whole blood and in serum were compared by the same method. Diacetylmorphine was hydrolyzed twice as rapidly in blood as in serum. While morphine was an end product of hydrolysis in the blood, it was absent in the serum.


Serum immunoreactive parathyroid hormone and 25-hydroxyvitamin D in patients with uremic bone diseases. Bone histologic parameters and serum iPTH and 25-OHD were measured in 20 patients with end-stage renal failure treated with hemodialysis. By bone histologic criteria, the patients were divided into three groups: mild, osteomalacic, and fibrotic. The increase in serum iPTH was much greater in the fibrotic group than in the mild or osteomalacic groups. In the uremic patients as a group, there were significant correlations between serum iPTH and both percent marrow fibrosis and percent resorbing surface. In the mild and fibrotic groups together, serum iPTH was also correlated with percent forming surface. This and other findings suggested that most of the bone changes in the mild and fibrotic groups could be explained by excess PTH. The difference in bone changes and in serum iPTH between the mild and fibrotic groups could be related to our eariler findings that duration of renal disease was much greater in the fibrotic than in the mild group. The lowest increment in serum iPTH was found in the osteomalacic group. In this group, percent resorbing surface was not increased and there was only a slight increase in marrow fibrosis. Thus in all three groups, serum iPTH appeared to reflect parathyroid status. The cause of the elevated serum iPTH and for the intergroup differences was not apparent inasmuch as serum calcium was normal in all three groups. Serum 25-OHD was significantly elevated in the osteomalacic and fibrotic groups. Because none of our patients had received preparations containing vitamin D, the elevated serum 25-OHD in the osteomalacic and fibrotic groups is consistent with altered vitamin D metabolism in these two groups. There was a direct relationship between percent osteroid area and serum 25-OHD. However, whether or not altered vitamin D metabolism contributed to the mineralization defect in uremic bone disease could not be established.


Conversion of androgens to estrogens in cirrhosis of the liver. The contribution, by peripheral conversion, of androstenedione and testosterone to the circulating estrogens was determined in men with cirrhosis of the liver. The conversion ratio of androstenedione to estrone, estradiol and testosterone and the conversion ratio of testosterone to estrone (but not estradiol) and androstenedione were significantly increased. The plasma concentrations of androstenedione and testosterone were increased and decreased respectively; the mean plasma concentration of androstenedione being similar to that found in normal women. The metabolic clearance rate of androstenedione was not altered in cirrhosis although the metabolic clearance rate of testosterone was decreased. The production rate of androstenedione was elevated while that of testosterone was reduced. The instantaneous contribution of plasma androstenedione to estrone and estradiol was increased in cirrhosis as was the contribution of testosterone to estrone (but not to estradiol). Thus the increased estradiol levels in cirrhosis result, in large part, from increased peripheral conversion from the androgens. The percent contribution of plasma testosterone to plasma androstenedione was decreased although the absolute amount derived by conversion was normal. The percent contribution of plasma androstenedione to plasma testosterone was increased sevenfold in cirrhosis. The fraction of the daily androstenedione production derived from the plasma testosterone pool was not significantly altered. However, a significant fraction of the daily production rate of testosterone was derived from androstenedione. Thus, 15% of the circulating testosterone is not secreted but is derived by peripheral conversion from androstenedione. Normal levels of gonadotropins were found in cirrhosis.


Nocturnal increase of plasma testosterone in men: relation to gonadotropins and prolactin. The nocturnal increase of plasma testosterone (T) in adult men has been well established. Luteinizing hormone (LH) does not show a similar increase throughout the night, whereas prolactin (PRL) does, suggesting the possibility of other hormone influence on T secretion. To investigate this possibility, 8 young adult men were studied for 4 consecutive nights in the sleep laboratory (2 nights adaptation, 2 nights blood sampling), by blood samples taken every 30 min during the 8-h sleep period, for measurement of LH, follicle stimulating hormone (FSH), PRL, and T. LH and FSH were secreted episodically, with little or no change in baseline levels during the night. PRL and T also were secreted episodically, but their baseline levels increased as the night progressed. Both LH and PRL had maximum within-subject correlations (averages equal +0.35 and +0.48 respectively) with T when they led T by 60 min. Within-subject correlations done on first differences (to remove the effect of slow trends) were near zero. LH and PRL had larger correlations with T than did FSH, for both calculations. These data suggest that both LH and PRL levels precede T levels by about 60 min. PRL thus may participate in the regulation of nocturnal T secretion in adult men.


Cortisol metabolism in chronic liver disease. Impairment of cortisol metabolism, evidence of endogenous hypercortism and sensitivity to oral corticosteroids are known to occur in patients with chronic liver disease. Measurements were made of plasma 11-OHCS and urinary cortisol levels and other parameters of adrenal function in a group of such patients. The mean plasma total 11-OHCS was lower in patients than in control subjects, although this difference was not statistically significant and the normal circadian rhythm was maintained. However, in patients with chronic liver disease a greater proportion of the 11-OHCS was in the non-protein bound state resulting in an elevation of this fraction. This elevation of non-protein bound 11-OHCS must represent a resetting of the pituitary-adrenal feedback mechanism in these patients. Corticosteroid binding globulin was lower in patients than in control subjects, although the difference was not statistically significant. Urinary cortisol excretion was significantly reduced as was excretion of 17-ketosteroids. Cortisol secretion rate was found to be normal. It is suggested that elevation of plasma non-protein bound 11-OHCS, resulting from impaired metabolism and reduced protein binding of cortisol in patients with hepatic disease, may explain the features of endogenous hypercorticism seen in such patients. Moreover, in the presence of impaired steroid metabolism and reduced protein binding, these patients may exhibit an increased sensitivity to corticosteroid therapy, and therefore administration of a reduced dosage may be advisable.


Production of estrone and fractional conversion of circulating androstenedione to estrone in women with endometrial carcinoma. Postmenopausal women convert circulatory C19 steroids to estrogen. In order to study the possible role of such estrogen in endometrial cancer, the determination of the fractional conversion of circulation delta-4-androstene-3,17-dione to estrone was attempted. However, in the course of this work it became apparent that the mathematical model upon which this determination is based does not adequately represent the true physiological conditions. The reasons for the inadequacy of the model are not apparent, although they seem to bear some relationship to obesity. The direction and magnitude of the deviation of the values; determined from the true values are unknown. The values for the apparent fractional conversion of androstenedione to estrone in 9 postmenopausal women with endometrial cancer are strongly correlated with values indices of obesity. These values also correlate well with values for the apparent rate of production of estrone in our 9 patients and also in 5 postomenopausal patients with uterine bleeding reported in the literature, but no such correlation is evident for postmenopausal women without endometrial abnormality reported in the literature. The range of values for both the apparent fractional conversion and the apparent rate of production of estrone are similar to those reported by other workers using the same model. However, the data suggest that women with endometrial cancer may produce estriol by a pathway not involving circulating estrone.


Metabolism of testosterone in previable human fetuses. Labeled testosterone was injected into the umbilical vein of each of 4 male and 3 female previable fetuses at the time of laparotomy. After leaving the circulation intact for 3 min, the fetal tissues of each fetus were removed and the labeled metabolites present in each tissue were extracted, separated and isolated. Aliquots of tissue extracts were used for the qualitative analysis of metabolites following which metabolites were reisolated quantitatively from other tissue aliquots with the aid of the corresponding 3-H-labeled recovery markers. Testosterone and 11beta-hydroxyandrostenedione-4 were isolated from the adrenals and 5beta-androstanedione, androstenedione, etiocholanolone, androsterone, 5alpha-androstanediol, 5beta-androstanediol and testosterone were isolated from the livers. In addition, etiocholanolone and 5beta-androstanediol were isolated from the sulfate and glucuronide fractions of the livers. A sex difference in fetal testosterone metabolism was observed in the liver where the amounts of unconjugated 5beta-androstanediol in the male livers with no overlap in values. This conclusion has to be viewed with caution as only 4 males and 3 female fetuses were examined in these studies.


Hormonal and metabolic changes induced by elevated plasma free fatty acids in term pregnancy. I. Effect on maternal blood glucose, insulin and human placental lactogen circulating levels. The influence of plasma free fatty acid (FFA) concentration on the secretion of human placental lactogen (hPL) was investigated in 16 normal young women during the last month of gestation, in order to determine whether hPL secretion is influenced in the same way as human growth hormone (hGH) during plasma FFA elevation. Maternal blood glucose (BG), plasma triglycerides (TG), FFA, immunoreactive insulin (IRI) and hPL levels were measured during and after a lipid emulsion infusion for 75 min (10 cases). The intravenous injection of 5,000 U of heparin at the 15th min of the lipid infusion was followed by a decrease in plasma triglyceride levels and by an accompanying rise in plasma FFA (rom 468 plus or minus 52 to 2,478 plus or minus 310 mueq/liter). In control experiments lipid infusion alone (3 cases) resulted in a moderate increase in FFA (718 plus or minus 157 to 1,046 plus or minus 255 mueq/liter), and separate iv heparin administration (3 cases) elevated the FFA levels from 728 plus or minus 50 to 1,649 plus or minus 153 mueq/liter). No significant change in either IRI or hPL levels was discernible in any of the tests performed. A tendency of blood glucose to increase was observed after heparin administration. It was concluded that a marked and sustained plasma FFA elevation, achieved through intravenous lipid and heparin infusion cannot alter hPL circulating levels in term human pregnancy.


In vitro determination of relative corticosteroid potency. The corticosteroid concentration required to inhibit phytohemagglutinin stimulated human lymphocyte transformation by 50% was determined for three corticosteroids. The relative potency of hydrocortisone, prednisolone and dexamethasone determined in 16 patients was 1.00, 2.43, and 24.7 respectively. This assay is proposed as an objective tool for comparison of relative corticosteroid potency in man.


Effectof sex, oral contraceptives, and glucose loading on apomorphine-induced growth hormone secretion. Apomorphine-induced growth hormone (GH) secretion less in women either on or off oral contraceptives than in men. Women on oral contraceptives have a significantly greater peak GH response to apomorphine than women on no medication. The reason for these differences is unclear. Prior glucose loading in men significantly decreases the GH response to apomorphine. This suggests that stimulation of glucoreceptors antagonises dopaminergic modulation of GH secretion.


Pituitary-gonadal response to acute I.M. stimulation with clomiphene citrate in normal men. In order to asses the effect of acute i.m. injection of clomiphene citrate (CC) on LH, FSH, and testosterone (T) secretion, five normal, fertile men received 5 mg of the drug dissolved in 2 ml 0.9% saline, while a further five were injected 10 mg of the same preparation. All tests were performed at 8 a.m. Blood samples were drawn at 0, 30, 60, 120 and 180 minutes of the injection. Serum LH, FSH, and T values were determined by the double antibody radioimmunoassay technique. A significant rise of the LH, FSH, and T levels was obtained in both groups. Peak LH values were obtained at 30 minutes (average), whereas FSH and T peaks occurred at 60 minutes. The 180-minute values were similar to basal. The results seem to indicate that intramsucularly administered CC could be useful, as a rapid test, in evaluating the function of the hypothalamic-pituitary-gonadal axis.


Twenty-four hour prolactin (PRL) secretory patterns during pregnancy. To determine if the central nervous system "program" controlling PRL secretion is operative during pregnancy, three pregnant women (12th, 20th and 32nd week of gestation) had 24-hour, 20-minute interval plasma sampling and polygraphic monitoring of nocturnal sleep. All three subjects showed episodic PRL secretion during waking which became augmented during nocturnal sleep. Since the number of "major" PRL secretory episodes was similar to normals, the increased PRL levels were most probably achieved by increased secretion per secretory episode. These findings suggest that during pregnancy, the PRL sleep related secretory "program" is maintained in a qualitative manner, albeit at a higher set-point.


Corticosteroids in human blood. VIII. Cortisol metabolites in plasma of normotensive subjects and patients with essential hypertension. Results of our previous studies revealed a derangement in the peripheral metabolism of adrenal steroids in patients with essential hypertension. To investigate further this finding, all indIVidual free and conjugated metabolites of cortisol were isolated, identified and quantitated in plasma of 14 normotensive subjects and 13 patients with benign, uncomplicated essential hypertension, following iv administration of a tracer dose of [4-14-C] cortisol. In addition, plasma levels of endogenous cortisol were determined at 8 AM and 4 PM in all the subjects examined. The results obtained revealed the following statistically significant differences between normotensives and hypertensives: 1) Mean plasma concentrations of cortisol metabolites reduced in ring-A with nonreduced 20-ketone, tetrahydrocortisol, tetrahydrocortisone, and their 5alpha-epimers, were 30% lower in the hypertensives; since these steroids constitute the bulk of the major group of cortisol metabolites--the glucuronide conjugates, plasma levels of this group of conjugates measured in toto were also found to be significantly lower in the hypertensives. 2) Concentrations of cortisol metabolites with non-reduced ring-A (delta-4-3-keto configuration preserved) but with reduced 20-ketone and/or hydroxylated at C-6, 20alpha- and 20beta- dihydrocortisol, 6alpha- and 6beta-hydroxycortisol, and 6-hydroxy-20-dihydrocortisol (all 4 isomers), were 73%, 48% and 68% respectively, higher in the hypertensives; since these steroids constitute the bulk of the sulfate-conjugated and nucleoside-complexed metabolites of cortisol, plasma levels of these groups of metabolites, measured in toto, were also found to be higher in the hypertensives. No significant difference was found between normotensives and hypertensives in the AM and PM plasma levels of cortisol. These findings, in conjunction with the results of our studies on urinary corticosteroid metabolites, which yielded identical findings, provide evidence for a decreased activity of hepatic cortisol-delta-4-hydrogenase enzyme system and increased activities (presumably compensatorily) of cortisol-20-reductase and 6-hydroxylase enzyme systems in patients with essential hypertension. The interrelation of these findings with those of other investigators studying steroid metabolites in hypertension, points to the corticosteroid metabolizing enzymes may be an etiological factor in essential hypertension.


Evaluation of azoestriol antisera for estriol measurements in pregnancy plasma directly and after extraction. 2-(4'-carboxyphenylazo)-estriol antisera were employed to quantitate pregnancy plasma estriol in ether extracts by single phase radioimmune assay without chromatography. Utilizing antiserum which crossreacted minimally even with the monoglucosiduronate metabolites, unextracted plasma estriol measurements were identical statistically to ether extract determinations.


Circulating 3,3', 5'-triiodothyronine (reverse T3) in the human newborn. Serum concentrations of 3,3',5'-triiodothyronine (reverse T3 rT3), 3,3',5-triiodothyronine (T), and thyroxine (T4) were measured in cord blood and invenous blood samples obtained between 2 h and 30 days of postnatal life from healthy full-term newborn infants. The mean serum rT3 concentration of (mean plus or minus SE) 151 plus or minus 12 ng per 100 ml in 18 cord blood samples was significantly higher than the level (41 plus or minus 2 ng per 100 ml) in 27 normal adult sera; the corresponding mean serum T4 of 12.7 plus or minus 0.8 mug per 100 ml in cord blood also was significantly higher than that (8.6 plus or minus 1.9 mug per 100 ml) in 108 normal adults. By contrast, the mean serum T3 concentration in 15 cord blood samples, 24 plus or minus 3 mg per 100 ml, was significantly lower than the value of 126 plus or minus 3.2 ng per 100 ml measured in 108 normal adults. At 4 h of age the mean serum rT3 concentration (165 plus or minus 13 ng per 100 ml) in six newborns was 4ot significantly different from that in paired cord blood samples (194 plus or minus 25 ng per 100 ml); on the other hand, whenever, studied, the mean serum T3 and T4 levels were significantly higher at 4 h than at birth. The failure of serum rT3 concentrations to rise after delivery in response to the early neonatal thyrotropin (TSH) surge and at a time when serum T3 and T4 levels increase significantly prompted a study of the rT3 response to 10 IU of intramuscular TSH in three healthy adult subjects. Just as in the newborns, serum rT3 failed to rise appreciably in these subjects, even though serum T3 and T4 showed the expected increments. Serum rT3 concentrations in 1-4 day-old newborn infants did not differ significantly from values in the cord blood but were significantly lower in older neonates. The mean serum rT3 level in 5-7-day-old infants was higher than that in normal adults, but in 9-11 day and 20-30-day-old infants, mean rT3 values were statistically similar to the adult value. The mean serum T3 concentrations in neonates between 1-30 days old were either higher than or comparable to the values of normal adults. The mean serum T4 concentrations in neonates between birth and 30 days of age were significantly higher than the mean adult level. The mean serum rT3 to T4 ratios (rT3/T4) were elevated in 1-4-day-old neonates; the values in older neonates were similar to those in adults. These results suggest that (a) factors other than TSH are important modulators of serum rT3 in man; (b) high serum rT3 concentration in the newborn becomes comparable to that in the normal adult by 9-11 days of neonatal life.


Uricosuric agents in uremic sera. Identification of indoxyl sulfata and hippuric acid. Serum and urine from chronically uremic patients and normal individuals were subjected to gel filtration of Sephadex-G10. The effects of the eluted fractions on the uptake of urate and para-aminohippurate by isolated cortical tubules of rabbit kidney were investigated. According to the origin of the samples, one to three major groups of fractions inhibiting both urate  and para-aminohippurate transport were disclosed. The first eluted group occurred for all the samples under study. The second one was demonstrated in both sera and urines from uremic patients but only in urines from normal individuals. The third one was exclusively detected in uremic sera and urines. Among all the compounds identified, only hippuric acid, eluted in the fractions of the second group, was capable of inhibiting the uptake of urate and para-aminohippurate in vitro. The concentration for which this inhbiitory effect of hippuric acid occurred was in the range of that existing in uremic sera. Indoxyl sulfate, which accumulates to very high concentrations in uremic serum, could not be disclosed in the above-mentioned fractions. This is explained by the strong adsorption of this indole derivative to Sephadex gel. Potassium indoxyl sulfate, when tested in vitro at the concentration existing in uremic serum, substantially inhibited the uptake of both urate and para-aminohippurate. In normal subjects, ingestion of hippuric acid or potassium indoxyl sulfate significantly increased fractional urinary excretion of uric acid. On the basis of these results, it is suggested that progressive retention of hippuric acid, indoxyl sulfate, and other yet unidentified inhibitors may explain the gradual increase in urinary fractional excretion of urate observed in uremia. The present results may be viewed as an example of a mechanism in which retention of normally excreted end products is responsible for adaptation of tubular transport in uremic subjects.


Pharmacokinetics of drugs in patients with the nephrotic syndrome. Since the binding of drugs to plasma proteins can significantly after the intensity of pharmacological and toxicological effects of drugs, we studied the pharmacokinetics of three drugs in patients with  hypoalbuminemia secondary to the nephrotic syndrome, but with relatively normal renal function. No significant differences were seen in the pharmacokinetic parameters observed for antipyrine, a drug which is less than 10% bound to plasms proteins. The percentage of unbound diphenylhydantoin, a highly plasms protein-bound drug, was found in patients with the nephrotic syndrome to be twice that of healthy individuals (19,2 vs. 10.1%, P smaller than 0.001). However, there was also a lower steady-state plasma concentration of diphenylhydantoin (2.9 plus or minus 0.6 vs. 6.8 plus or minus 0.6 mug/ml, P smaller than 0.001) secondary to an increase in the plasms clearance (0.048 plus or minus 0.019 vs. 0.022 plus or minus 0.006 liter/kg.h, P smaller than 0.001) in the nephrotic patients. The net effect is no difference in the absolute concentration of unbound diphenylhydantoin in healthy individuals (0.69 plus or minus 0.05 mug/ml) and patients with the nephrotic syndrome (0.59 plus or minus 0.06 mug/ml). Qualitatively, similar differences were observed with clofibrate. The dose of these drugs need not be routinely reduced in patients with the nephrotic syndrome as long as they have reasonably normal renal function (creatinine clearance greater than 50 ml/min). With all highly bound acidic drugs, knowledge of the concentration of unbound drug is essential to the proper interpretation of total blood levels and subsequent treatment of the patient.


Idiopathic scoliosis. Mechanical properties of the respiratory system and the ventilatory response to carbon dioxide. The aims were to examine the effects of scoliosis (angle), and age on lung volumes, elastic properties of the respiratory system, and the ventilatory response to CO2. The mean age of the 55 patients was 25.4 plus or minus SEM 2.5 yr, and the mean angle was 80 plus or minus SEM 4.2. The mean plus or minus SEM percent predicted lung volumes were vital capacity (VC), 60.5 plus or minus 2.7; total lung capacity (TLC), 70,2 plus or minus 2.6; functional residual capacity (frc), 79.3 plus or minus 3.2; and residual volume (RV), 99.7 plus or minus 5.2. The correlation coefficients between the angle of scoliosis and each of the following were significant: TLC (-0.548), percent predicted TLC (-0.547), VC (-0.485), percent predicted VC (-0.523), FRC (-0.533), percent predicted FRC (-0.338), RV (-0.438), and percent predicted RV (-0.318). The mean compliance of the total respiratory system (Crs) was 0.049 litter/cm H2O plus or minus SEM 0.004, and the mean compliance of the chest wall (Ccw) was 0.080 liter/cm H2O plus or minus SEM 0.012. The Crs and Ccw were inversely proportional to the angle (r-0.620 and -0.721) and directly proportional to the height and the weight. The mean deltaV/deltaPco2 was 1.32 liter/min per mm Hg (SEM 0.171), and the mean deltaVt/deltaPco2 was 28.9 ml/mm Hg (SEM 3.64). The correlation coefficients between deltaV/deltaPco2 and the following were height, 0.499; VC, 0.792; TLC, 0.632; AND Crs, 0.520; and between the deltaTt/deltaPco2 and the following were height, 0.500; VC, 0.878; TLC, 0.802; and Crs, 0.590. We conclude that body size and the deformity were the determinants of the lung volumes and the mechanical properties of the respiratory system, and that these variables were the major factors in both the magnitude and pattern of the ventilatory response to CO2. The correlations between age and the mechanical properties of the respiratory sytem, deltaV/deltaPco2, and deltaVt/deltaPco2, were not significant, but the correlation coefficients between age and several of the derivatives of deltaV/deltaPco2 and deltaVt/deltaPco2 were significant.


Defective alpha-polymerization in the conversion of fibrinogen Baltimore to fibrin. The subunit structure of fibrinogen Baltimore and fibrin formed from this inherited dysfibrinogenemia was analyzed by polyacrylamide gel electrophoresis in sodium dodecyl sulfate. The molecular weights of the alpha-, b- and gamma-chains of fibrinogen Baltimore were found to be identical to those of normal fibrinogen. Noncross-linked fibrin formed from both purified fibrinogen Baltimore as well as normal fibrinogen contained two alpha-monomers (alpha1 and alpha2). alpha2 was presumed to be alpha-monomer from which fibrinopeptide A had been released. The evolution of alpha2 during clotting of fibrinogen Baltimore was delayed and appeared to be quantitatively reduced when compared to normal. Crosslinked fibrin formed from fibrinogen Baltimore possessed an abnormal subunit structure. alpha-polymers were not generated in thrombin-induced, factor XIII-rich clots of fibrinogen Baltimore under conditions of pH and calcium concentration suitable for complete alpha-polymerization in normal fibrin. If clotting was carried out with calcium concentrations twice that required for normal clots or at pH 6.4, fibrin from fibrinogen Baltimore was completely cross-linked. These structural analyses of fibrin formed from fibrinogen Baltimore substantiate earlier findings that indicate a defect in the alpha-chain of this dysfibrinogenemia.


Effects of a molecular change in collagen on lung structure and mechanical function. Semicarbazide, a lathyrogen, was given to growing rats to elucidate the consequences of altering the molecular structure of fibrous proteins within the lung. Static pressure-volume (P-V) measurements during deflation of saline-filled lungs showed normal recoil pressure and compliance values within the physiological range of lung volume. Quasi-static P-V measurements were also normal during slow reinflation, even beyond physiological limits to a recoil pressure of 20 cm H20. However, the lungs of experimental rats ruptured at much lower recoil pressures than controls. Histology was normal in lungs fixed at 20 cm H20. In contrast, lungs showed dilation of terminal air spaces, rupture of alveolar walls, and an increase in mean linear intercept in experimental compared with control specimens, when fixed at 30 cm H20. Biochemical analyses revealed reduced cross-linking of lung collagen without change in its total content. There were no detectable changes in the quantity or quality of lung elastin. It is concluded that semicarbazide may selectively impair the maturation of lung collagen and that immaturity of lung collagen is associated with a reduction in the tensile strength of lung tissue, without changes in elasticity within physiological volume limits.


Hormonal control of ketogenesis. Rapid activation of hepatic ketogenic capacity in fed rats by anti-insulin serum and glucagon. The enhanced capacity for long-chain fatty acid oxidation and ketogenesis that develops in the rat liver between 6 and 9 h after the onset of starvation was shown to be inducible much more rapidly by administration of anti-insulin serum or glucagon to fed rats. After only 1 h of treatment with either agent, the liver had clearly switched from a "nonketogenic" to a "ketogenic" profile, as determined by rates of acetoacetate and b-hydroxybutyrate production on perfusion with oleic acid. As was the case after starvation, the administration of insulin antibodies or glucagon resulted in depletion of hepatic glycogen stores and a proportional increase in the ability of the liver to oxidize long-chain fatty acids and (-)-octanoylcarnitine, suggesting that all three treatment schedules activated the carnitine acyltransferase system of enzymes. In contrast to anti-insulin serum, which produced marked elevations in plasma glucose, free fatty acid, and ketone body concentrations, glucagon treatment had little effect on any of these parameters, presumably due to enhanced insulin secretion after the initial stimulation of glycogenolysis. Thus, after treatment with glucagon alone, it was possible to obtain a "ketogenic" liver from a nonketotic animal. The results are consistent with the possibility that the activity of carnitine acyltransferase, and thus ketogenic capacity, is subject to bihormonal control through the relative blood concentrations of insulin and glucagon, as also appears to be the case with hepatic carbohydrate metabolism.


Behavior of eosinophil leukocytes in acute inflammation. I. Lack of dependence on adrenal function. Acute infection is accompanied by a characteristic reduction in circulating eosinophils. This study examined the generally held assumption that the eosinopenia of infection is a manifestation of adrenal stimulation. Trichinosis, Escherichia coli pyelonephritis, and early subcutaneous pneumococcal abscess were used as experimental infections of limited severity. Trichinosis is associated with eosinophilia, but pyelonephritis and pneumococcal infection produce eosinopenia. An assay for serum corticosterone was developed that is sufficiently sensitive to be performed with the small volumes of blood obtained sequentially from individual mice. The corticosterone response to trichinosis fits the sterotyped reaction previously reported for several other bacterial, viral, and rickettsial infections. The peak concentrations of corticosterone in serum from mice with trichinosis was approximately twice normal and occurred at the onset of clinical illness. Serum corticosterone levels gradually declined to the normal range over the next several days. E. coli pyelonephritis produced a similar adrenal response, although the peak serum corticosterone caused by pyelonephritis was less than the serum corticosterone occurring during the first peak of eosinophilia during trichinosis. Infection of a subcutaneous air pouch with penumococci produced eosinopenia within 6 h after inoculation, but there was no rise in serum corticosterone during the first 12 h of the pneumococcal infection. In addition, the eosinopenic response produced by a 12-hpneumococcal abscess occurred mice adrenalectomized 1-4 days before infection with pneumococci. The eosinopenia of acute infection cannot be ascribed to adrenal stimulation.


Lymphocytotoxic antibodies in family members of patients with systemic lupus erythematosus. 57% of sera from 124 relatives of 28 patients with systemic lupus erythematosus (SLE) were found to have antibody directed against lymphocytes. The incidence in 60 members of 16 control families was 3%. Both consanguineous and nonconsanguineous relatives had the antibody in their sera. 68% of close household contacts of the SLE patients showed lymphocytotoxic antibody whereas only 23% of consanguineous relatives who had no household contact with the probands had this antibody. These data suggest that environmental factors may be important in the pathogenesis of SLE.


Characteristics of salt and water transport in superficial and juxtamedullary straight segments of proximal tubules. The purpose of the present studies was to characterize the nature of salt and water transport out of the superficial (SF) and juxtamedullary (JM) straight segments of rabbit proximal tubules as examined by in vitro microperfusion techniques. When the perfusate consisted of a solution simulating ultrafiltrate of plasma, there were no differences between SF and JM straight tubules in either net reabsorption of fluid (SF=0.47 nl/mm per min; JM=0.56 nl/mm per min) or in transtubular potential difference (PD) (SF=-2.1 mV; JM=-1.8 mV). Removal of glucose and alanine from the perfusate had no effect on the magnitude of the PD in either straight segment. Ouabain decreased both the net reabsorptive rates and the PD. Isosmolal replacement of NaCL by Na-cyclamate (a presumed impermeant anion) in the perfusate and the bath caused an increase in luminal negativity in both segments wheras similar substitution of NaCL by choline-CL (nontransported cation) changed the PD TO NEAR ZERO. These studies, therefore, suggest that sodium is transported out of the proximal straight tubules by an active noncoupled process that generates a PD (electrogenic process). When the perfusate consisted of a solution with a high chloride concentration (resulting from greater HCO3 than CI reabsorption in the proximal convoluted tubule), different PDs in SF and JM tubules were generated: SF=+1.6 plus or minus 0.2 mV; JM=-1.3 plus or minus 0.3 mV. This difference in PD was attributed to relative differences in Na and CI permeabilities in these two segments. Electrophysiological and isotopic estimates of the chloride to sodium permeability revealed that the SF tubule is about twice as permeant to chloride than to sodium whereas the JM tubules are approximately twice as permeant to sodium than to chloride. It is concluded that the mechanism of active sodium transport in the straight segment of proximal tubule differs from that of the convoluted segment and that both the SF and JM straight segments differ from each other with respect os sodium and chloride permeability.


Proinsulin, insulin, and C-peptide concentrations in human portal and peripheral blood. Concentrations of insulin, proinsulin, and C-peptide were measured in portal and peripheral venous blood in six nondiabetic, nonobese subjects. Portal vein samples were obtained by umbilical vein catheterization. Three subjects were studied with intravenous infusion of 25 g glucose, and three with 30 g arginine. Insulin and proinsulin were determined in the insulin immunoassay after separation by gel filtration, and C-peptide was measured by direct immunoassay. With both glucose and arginine stimulation, portal vein levels of all three peptides peaked at 90-120 s after the onset of the stimulus. Relative increases in insulin concentration were greater than those of proinsulin or C-peptide. In peripheral venous blood, maximal levels of the three peptides were observed later (2-5 min), and the increase in insulin relative toproinsulin and C-peptide was not as great. At the time of peak secretion, portal vein insulin and C-peptide approached equimolar concentrations, and proinsulin, as measured against an insulin standard, comprised approximately 2.5% of the total immunoreactive insulin. After stimulation by glucose or arginine, portal insulin, proinsulin and C-peptide levels were not correlated with the concentrations measured in simultaneously drawn peripheral samples. At all sampling times, however, significant correlation was found between insulin and C-peptide in both peripheral and portal blood. The results indicate that under the conditions studied, insulin and C-peptide are secreted in equimolar concentrations in man, and that proinsulin is secreted in the same proportion to insulin as found in the pancreas. Consideration of the relative secretory and metabolic rates of the three beta cell peptides explains their peripheral concentrations. The data further support the use of plasma C-peptide as an indicator of beta cell secretory function.


A functional comparison of the cortical collecting tubule and the distal convoluted tubule. Electrical and permeability features of the distal convoluted tubule (DCT) and the cortical collecting tubule (CCT) were examined using the technique in which isolated segments of rabbit tubules were perfused in vitro. When rabbits were given a regular diet and tubules were perfused and bathed in artificial solutions simulating plasma ultrafiltrate, the potential difference (PD) was +3.7 plus or minus 1.9 mV in the CCT and -40.4 plus or minus 2.8 mV in the DCT. When rabbits were given a low sodium, high potassium diet plus i.m. deoxycorticosterone acetate (DOCA) (1 mg/kg per day), the PD in both the CCT (-30.8 plus or minus 3.9 mV) and the DCT (-33.8 plus or minus 5.5 mV) was negative. The PD in the CCT was quantitatively similar to that of diet plus DOCA when animals were given DOCA alone. The PD in both segments was inhibited by ouabain (10-minus 5 M) in the bath or by amiloride (10-minus 5 M) in the perfusate. Addition of vasopressin (200 muU/ml) to the bath caused a gradual decline of PD to zero in the CCT but failed to produce a potential response in the DCT. Osmotic water permeability was essentially zero in both segments in the absence of vasopressin. After addition of the vasopressin to the bath, osmotic water permeability in the DCT remained zero but increased to 71.9 plus or minus 25.5 X 10-minus 7 cm/s per atm in the CCT. We conclude that both segments are similar in that each possesses an electrogenic transport process but that these segments differ in that: (a) the CCT requires either exogenous or endogenous mineralocorticoid to maintain a maximal negative PD, whereas the PD in the DCT appears to be independent of mineralocorticoid effect; and (b) the CCT responds to vasopressin with a marked rise in water permeability, whereas the DCT is impermeable to water before and after addition of vasopressin.


The acute effect of chlorothiazide on serum-ionized calcium. Evidence for a parathyroid hormone-dependent mechanism. The acute effects of chlorothiazide (CTZ) on total (TSCA) and ionized (SCA-plus 2) serum calcium concentrations were studied in three groups of people: (a) eight subjects with normal parathyroid function; (b) six patients with hypoparathyroidism; and (c) two patients with hyperparathyroidism. Most subjects were studied on four occasions; at least 3 days intervened between studies on an individual subject. During each experiment the subject received an i.v. influsion of 5% dextrose in water at 1 ml/min from 8 a.m. to 4 p.m. Additions to the infusions were (a) none; (b) CTZ to deliver 3.33 mg/kg/h; (c) parathyroid extract to deliver 1 U/kg/h; or (d) both CTZ and parathyroid extract at the rates previously indicated. CTZ, when used, was added to the infusion at 10 a.m., parathyroid extract at 8 a.m. When CTZ was infused, the diuretic-induced losses of Na and water were replaced by i.v. infusion. In normal subjects 2 h after the start of CTZ infusion, there was a transient increase in SCA-plus 2 which coincided in time of day with a transient decrease in SCA-plus 2 in control experiments. At that time of day SCA-plus 2 was 4.18 plus or minus 0.12 mg/100 ml in control experiments and 4.56 plus or minus 0.08 in experiments with CTZ, P smaller than 0.025. The corresponding values for (TSCA) were 9.32 plus or minus 0.15 and 9.80 plus or minus 0.30, P smaller than 0.01. Such differences were not observed in the group with hypoparathyroidism. In the two patients with hyperparathyroidism, CTZ produced sustained increases in TSCA and SCA-plus 2. In normal subjects and those with hypoparathyroidism, CTZ plus parathyroid extract infusion resulted in sustained increases in both SCA-plus 2 and TSCA throughout the periods of observation when compared to experiments in which only parathyroid extract was infused, P smaller than 0.01 in all instances. The results suggest that the acute hypercalcemic action of CTZ requires the presence of circulating parathyroid hormone.