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The anion transport, "band 3," family of proteins in mammalian brain performs the same functions as that of erythroid band 3. These functions are anion transport, ankyrin binding, and generation of senescent cell antigen, an aging antigen that terminates the life of cells. The presence of 5-7 band 3 related proteins in brain tissue was suggested by the reaction of antibodies to synthetic peptides of erythroid band 3 with a number of bands in immunoblots. Since there are a number of different cell types in brain, tissue cultures of neural cell types were examined to determine whether multiple band 3 related proteins are present in each cell type or whether several band 3 related proteins are present in each cell type. The tumor cell lines exhibit anion transport and are inhibited by the anion transport inhibitors 4,4'-diisothiocyano-2,2' disulfonic acid (DIDS), phenylglyoxal, and furosemide. Glucose transport is inhibited by cytochalasin B and the anion transport inhibitor, phenylglyoxal, in these cell lines, but not by 4,4'-diisothiocyano-2,2' disulfonic acid. Furosemide gave partial inhibition of most, but not all, cell lines. Since phenylglyoxal inhibits anion transport by binding to an arginine near the transport site, inhibition of glucose transport by phenylglyoxal suggests that an arginine lies in the substrate binding site. The number of cytochalasin B and DIDS binding sites was quantitated on cell lines as an approximation of the number of glucose transporter and anion transporter sites, respectively.

Osteopathia striata is an unusual skeletal condition that can affect the bones of the skull quite markedly and result in dental problems that have rarely been discussed in the literature. The characteristic features exhibited by the patient in this case report were dense maxillary and mandibular bone, a high forehead with frontal bossing, a broad nasal bridge, prominent zygomatic arches and thickened angles of the mandible. The mouth opening was limited as a result of sclerosis of the mastoid process, and right lateral excursion of the mandible was reduced, probably because of a deformity of the left condyle.

Some concern has been expressed in recent years about the use of formocresol for vital pulpotomy treatment of primary molars. This paper reviews the literature concerning the toxicity of formocresol and considers the evidence for the use of calcium hydroxide and glutaraldehyde. It is concluded that more work is required in this field before an alternative to formocresol can be recommended and that, in the meantime, a 1:5 dilution of the standard formocresol solution should be used but not included in the zinc oxide-eugenol sublining.

Oxygen conserving devices, the TTO catheters, electronic pulsed DODS and reservoir cannulas, increase efficacy of oxygen delivery; TTO also improves cosmetic appearance, comfort and compliance. We speculated that pulsing of oxygen transtracheally can increase efficiency of TTO. We modified the DODS to include settable delays and a rapid pre-inspiratory trigger. The first part of the study was performed with nasal oxygen on seven subjects and the second part, with TTO on 17 subjects. Nasal oxygen results indicate improved delivery efficiency with more rapid response. The TTO results indicate no significant change for each delay setting, but there was improvement in delivery efficiency when DODS was combined with TTO vs continuous flow TTO. Thus, early inspiratory delivery increases efficiency of oxygen therapy. Small delays in response time are critical in nasal delivery but not important in TTO. Pulsed TTO is more efficient than continuous flow TTO and merits long-term studies.

Facultatively anaerobic and strictly anaerobic bacteria colonizing the intestinal tracts of 14-day-old chicks fed a corn-based diet were enumerated, isolated, and identified. Colony counts from anaerobic roll tubes (rumen fluid medium) or aerobic plates (brain heart infusion agar) recovered from homogenates of the duodenum, upper and lower ileum, and cecum varied appreciably among samples from individual birds. Anaerobic and aerobic counts from the duodenum and ileum were similar. Anaerobic counts were highest from the cecum (0.7 X 10(11) to 1.6 X 10(11)/g of dry tissue) and exceeded aerobic plate counts by a factor of at least 10(2). Facultatively anaerobic groups (Streptococcus, Staphylococcus, Lactobacillus, and Escherichia coli) comprised the predominant flora of the duodenum and ileum, although large numbers of anaerobes (9 to 39% of the small intestine isolates), represented by species of Eubacterium, Propionibacterium, Clostridium, Gemmiger, and Fusobacterium, were also recovered. Strict anaerobes (anaerobic gram-positive cocci, Eubacterium, Clostridium Gemmiger, Fusobacterium, and Bacteriodes) made up nearly the entire microbial population of the cecum. Scanning electron microscopy of the intestinal epithelia of chicks revealed populations of microbes on the duodenal, ileal, and cecal mucosal surfaces.

Differentiation and growth of swine subcutaneous adipose tissue was assessed by chemical analysis of tissue components, cell size measurements of isolated adipocytes, and light and electron microscopic observations. At birth all adipocytes were multilocular (contained multiple small lipid droplets), but by day 3 postpartum, many were already differentiated to the unilocular state (one major, central lipid droplet). Microscopic observations of fixed tissue, cell size determinations on isolated adipocytes, and chemical analysis of tissue composition indicated a marked increase in adipocyte size accompanied by an increase in the size of the central lipid droplet with age. Small cells were observed at all ages (in both fixed tissue and isolated cell preparations), yielding biphasic size distributions. Although the adipocyte stem cell was not discerned, an early stage in differentiation, designated an adipoblast, was observed.

A 12-year-old girl developed Takayasu's arteritis (pulseless disease) within a month of the appearance of tuberculous cervical adenitis. This unusual form of arteritis is common in Japan and Korea but has rarely been reported in individuals born in the United States. The etiology is unclear. The literature currently hypothesizes an autoimmune basis and treatment with steroids. Although a tuberculin sensitization pathogenesis has been suggested, a close temporal relationship with the onset of a tuberculous process has not previously been documented. The likelihood of uncovering tuberculin sensitivity or active tuberculosis in patients with Takayasu's arteritis is substantially higher than in the general population in all countries analyzed. The natural history of this arteritis is highly variable. The adolescent described in this paper has demonstrated complete symptomatic remission as well as return of pulses simultaneous with antituberculosis therapy.

The combination of interstitial nephritis and minimal-change nephrotic syndrome has been well described in adults receiving nonsteroidal anti-inflammatory agents. The association of interstitial nephritis and minimal-change nephrotic syndrome has recently been described in 1 adult patient receiving ampicillin and in 1 patient receiving rifampin. We describe an 8-month-old child who developed reversible interstitial nephritis and minimal-change nephrotic syndrome while taking antibiotics.

In prospectively evaluating 100 cases of adolescents with chest pain (along with two control groups), 91 were found to have recurrent chest pain; fewer than 5 had a serious organic cause. Significantly higher school absenteeism occurred in patients with either chest or abdominal pain than in patients without pain. Adolescents with chest and abdominal pain were more likely to be high users of medical services than those with no pain. Most adolescents believed that persons their age could have attacks; 44 of those with chest pain thought their symptom was due to a heart attack. The occurrence of chest pain was not influenced by an adolescent's age, sex, race, smoking status or family structure, nor was it consistently associated with depression. Chest pain is thus a common problem of adolescence that produces considerable functional impairment not attributable to serious underlying disease.

Lamination of the basement membrane has been considered to be the lesion characteristic of familial nephritis and attenuation to be the lesion of "Benign" familial hematuria. Electron micrographs were reviewed of 57 children who had renal biopsies for persistent hematuria. Attenuation or lamination of the glomerular capillary basement membrane was found in each. Twenty of the 57 children had familial nephritis; 20 had familial hematuria; and 17 had no involved relatives. Follow-up data were available for 14 of 20 children with familial nephritis, 12 of 20 with familial hematuria, and 12 of 17 with sporadic hematuria for 13.6 +/- 6.3, 6.7 +/- 4.6, and 7.0 +/- 4.8 years, respectively, after discovery of hematuria. Five children developed end-stage renal disease: three with familial nephritis, one with familial hematuria, and one with sporadic hematuria. Only two no longer had hematuria. Attenuation of the glomerular capillary basement membrane was seen in every biopsy, whereas lamination was not. Because hematuria and ultrastructural abnormalities were findings shared by all the children, we suggest the possibility that familial nephritis, and familial or sporadic hematuria as defined in this study, may be variations in a spectrum of inherited abnormality or abnormalities in the formation of the glomerular capillary basement membrane.

A 16-year-old boy with primary intestinal lymphangiectasia presented with peripheral edema of 6 weeks duration. Laboratory and radiological studies included absolute lymphopenia, hypoalbuminemia, steatorrhea, abnormal stool 51Cr-albumin value, edema of small intestinal folds, dilated mesenteric lymphatics, as well as bilateral filling defects in external and common iliac lymph nodes. Abdominal CT scan revealed a possible periaortic mass. Small intestinal biopsies demonstrated normal villous architecture with dilated lacteals, and electron microscopy revealed enterocytes with normal as well as blunted microville, enlarged, dilated lacteals and intercellular vacuoles. An exploratory laparatomy was performed and revealed no masses but dilated serosal lymphatic vessels. Medical treatment, including marked restriction of long chain triglyceride intake, resulted in loss of peripheral edema, weight stabilization, and normal activity.

Female NZB/NZW F1 mice were treated as adults with 5-alpha-dihydrotestosterone powder packed into subcutaneous implants. Two treatment protocols were followed: (a) 3-mo-old mice received 6 mg of androgen, and (b) 6-mo-old mice were castrated and given 12 mg of androgen. Sham females received empty implants. Mice were followed monthly for surival, for antibodies to DNA and polyadenylic acid, and for renal histopathology. The percent survival at 11 mo was 74% for mice treated at 3 mo, compared to 11% for the sham controls, and 100% for mice treated at 6 mo, compared to 20% for their sham controls. Androgen-treated mice had less immune complex glomerulonephritis as determined by immunofluorescent and electron microscopy. Surprisingly, treated mice had no significant sustained reduction in antibodies to DNA although they had reduced antibodies to polyadenylic acid. These results suggest that androgens can still prolong survival and reduce immune complex deposition even when treatment is delayed to an age when disease is relatively established. After delayed androgen treatment, mice survive despite the presence of high levels of IgG antibodies to DNA.

Six conditions cause most of the neck pain complaints seen by primary care physicians: cervical muscle strain or sprain, torticollis, acceleration injury, myofascial pain dysfunction syndrome, and cervical osteoarthritis or rheumatoid arthritis. Most of them can be diagnosed and treated by the primary care physician. Of the more unusual causes, one should not miss a clinical fracture; a herniated cervical disc, spinal cord compression from a disc, or epidural tumor; infection of the disc or the vertebral body; subluxation of the vertebral bodies; or pain referred from the chest or mediastinal structures. MRI offers new opportunity for early diagnosis of myelopathy owing to OA or RA, vertebral osteomyelitis, and metastatic involvement of cervical vertebrae.

Naturally occurring autoantibodies to band 3 in normal human serum do not bind to red cells unless they are senescent, stored, or damaged. We suspected that IgG did not bind to native band 3 in intact red cells because of steric "shielding" of band 3 by adjacent molecules such as the glycophorins. In order to test this hypothesis, immunoelectron microscopy experiments were performed on intact red cells and red cells subjected to enzymatic treatment. Results revealed that antibodies to band 3 did not bind to untreated red cells, but did bind to red cells treated with trypsin, which spares band 3 but cleaves glycophorins A and C. Treatment with alpha-chymotrypsin did not significantly increase antiband 3 antibody binding. Binding of antibodies to the senescent cell antigen was not increased by either enzymatic treatment. It appears that binding of antibodies to the senescent cell antigen requires more than exposure of band 3 and proteolysis at a site other than the alpha-chymotrypsin sensitive site in intact red cells.

NZB/NZW F1 mice of both sexes were castrated at 2 wk of age and implanted subcutaneously with silastic tubes containing either 5-alpha-dihydrotestosterone or estradiol-17-beta. Mice receiving androgen showed improved survival, reduced anti-nucleic acid antibodies, or less evidence of glomerulonephritis as determined by light, immunofluorescent, and electron microscopy. By contrast, opposite effects were observed in castrated mice receiving estrogen. Intact male NZB/NZW F1 mice received androgen implants at 8 mo, an age when they develop an accelerated autoimmune disease associated with a decline in serum testosterone concentration. Such treated mice had improved survival and reduced concentrations of antibodies to DNA and to polyadenylic acid (Poly A). Prepubertal castration of male NZB/NZW F1 mice results in an earlier appearance of IgG antibodies to Poly A. This effect of castration was prevented if neonatal thymectomy was also performed.

Among nonhuman primates, the renal anatomy of the spider monkey (Ateles geoffroyi) is unique, as it is multipyramidal and multipapillary. Renal function parameters (glomerular filtration rate, renal plasma flow, and concentrating ability) are compared to man and other primates. The kidneys of the spider monkey are similar both anatomically and functionally to man.

Band 3, the major transmembrane polypeptide of erythrocytes, mediates the exchange of anions (chloride and bicarbonate) across the membrane. We suspected that band 3 was present on nucleated somatic cells as well as erythrocytes because the senescent cell antigen that is immunologically related to band 3 is present on lymphocytes, platelets, adult liver cells, and embryonic kidney cells; and antibodies prepared against the senescent cell antigen isolated from leukocytes react with erythrocyte band 3. For this reason, we examined human fibroblasts, lung cells, neutrophils, mononuclear leukocytes, squamous epithelial (mouth) cells, lung squamous epithelial carcinoma, mouse neuroblastoma cells, and rat hepatocytes for immunoreactive forms of band 3 by using monospecific antibodies to erythrocyte band 3. The results demonstrated that polypeptides sharing common antigenic determinants with erythrocyte band 3 are present in nucleated somatic cells as determined by immunofluorescence, immunoelectron microscopy, and immunoautoradiography. Peptide mapping revealed substantial sequence homology between erythrocyte band 3 and the band 3-like protein of leukocytes. Immunofluorescence studies indicate that the band 3-like proteins in nucleated cells participate in antibody-induced cell surface capping.

Distribution of federal funds has achieved equal status with Congressional reapportionment as a motivation and justification for the Census of Population and Housing. This article describes the effects that U.S. population redistribution during the 1970s, as measured by the 1980 Census, will have on the spatial distribution of federal grants-in-aid provided to state and local governments through programs with formula-based funding systems. The conclusion is that funding changes will not match population changes. The overall redistribution of federal grants-in-aid to state and local governments occurring in response to incorporation of 1980 Census population counts into federal funding formulas will be far less than the level of population redistribution since 1970. Use of intercensal data, formula specifications, limited geographic specificity in many formula allocations, and nonformula determinants of formula-based grants all weaken the relationship between Census-measured population change and the receipt of federal funds at the local level. Despite all the intervening factors, it is probably that in many programs there will be some redistribution of funds when the 1980 Census counts are incorporated into the allocation formulas. But the importance of measurement errors and threshold and reclassification effects may equal that of true population change in determining the funds received by local communities.

Family practice physicians' perceptions of the usefulness and clinical outcome of drug therapy recommendations made by clinical pharmacists in a family medicine clinic were determined. For 15 weeks, pharmacists in the clinic recorded all consultations in which they made recommendations about the drug therapy of specific patients. At the time of each consultation, the pharmacists gave the physician a questionnaire designed to gauge the physician's opinion of the usefulness of the consultation. Physicians who implemented the recommendations were sent a second questionnaire and asked to indicate the extent to which the clinical pharmacist influenced their decision to implement the recommendation, the effect the recommendation had on the patient's clinical status, and the usefulness of the recommendation to the patient in ways unrelated to clinical status (such as greater patient acceptance, safety, or lower cost). Five clinical pharmacists provided 59 consultations to 33 physicians. The physicians rated 51 (88%) of the consultations as very useful, and they implemented 78 (98%) of the 80 recommended actions. Of the 56 physicians who attributed their decision to implement the recommendation to their consultation with the clinical pharmacist, 43 believed that the recommendations had improved the clinical status of the patient, and 38 believed that the recommendations were useful to patients in ways unrelated to clinical status. Physicians in a family medicine residency training program had positive perceptions of the usefulness of drug therapy recommendations made by clinical pharmacists. A majority of the physicians believed that the recommendations had a positive effect on patients' clinical status.

It is easy to distort the "truth" in morphological reports in order to confirm a previously established dogma by selecting from a field of view only such details which are in accordance with the dogma and by ignoring parts contradictory to it. The renal corpuscle is used in this paper as an example and as a guide to the readers for future fraud.

The distribution of calcium phosphate granules in mitochondria of proximal and distal renal tubules of nonuremic and uremic children was analyzed by electron microscopy of material obtained by percutaneous kidney biopsy. Although distal tubule had fewer granules/mitochondrion than proximal tubule, uremia induced a significant drop (50%) in both, related to an increase in mitochondria containing O granules and a decrease in mitochondria with 2+ granules. The decrease observed in uremic children was reproduced experimentally by partial nephrectomy in rats. Uremia resulted in a 58% decrease of calcium phosphate granules in rat proximal tubule while a smaller but significant decrease (36%) occurred in distal tubule. Vitamin D deficiency in rats was associated with greatly decreased granulation in proximal tubule (80%) whereas distal tubule was less severely affected (36%). Supplementation of vitamin D to uremic rats restored mitochondrial granulation to normal in proximal tubule in 24 hr, but had no effect in distal tubule since the number of granules/mitochondrion, 0.5 +/- 0.1, remained statistically similar to that of untreated animals. Granulation in both proximal and distal tubule of uremic rats was unaffected by parathyroid hormone administration. Since restoration of granulation occurred only in proximal tubule, the defect in uremia which can be overcome by vitamin D treatment appears localized at the level of the proximal tubular cell membrane, indicating an action of vitamin D on calcium and/or phosphorus translocation into the proximal tubule.

Removable partial dentures (RPDs) are frequently used in the treatment of severe hypodontia. The failure rates and modes of failure of 138 such prostheses incorporating acrylic resin onlays were assessed in a retrospective survey. Failures primarily occurred either early or late in the life of the prostheses. Particular problems identified were the low wear resistance of acrylic resin onlays and poor fixation of resin components to metal bases, especially when space was limited.

Studies of early progressive vitiligo, Vogt-Koyanagi syndrome, and incontinentia pigmenti achromians were made by electron microscopy. At the periphery of the depigmented lesion, the melanocytes had several subcellular abnormalities, ie, vacuolization of the cytoplasm, aggregation of melanosomes, autophagic vacuoles, fatty degeneration, pyknosis or homogeneous cytoplasmic degeneration, and others. Numerous nerve endings were seen in close contact with the basal lamina of the epidermis or even within the epidermis. Direct continuities between Schwann cell basal lamina of nerve endings and the basal lamina of the melanocytes were observed. Nerve endings could be associated with either normal or abnormal melanocytes.

A spontaneously occurring antibasement membrane antibody has been further characterised according to antigenic specificity, immunoglobulin class, and tissue localisation using immunofluorescent and immunoelectron microscopic techniques. The autoantibody reacted with the basement membrane of kidney tubules, Bowman's capsule, and the epithelial portion of ileum but not with the basement membrane of skin, cornea, glomerulus, or oesophagus. It also reacted with bile canaliculi, sarcolemmal sheath, and salivary duct. On electron microscopy the antibody was distributed along the basement membrane of Bowman's capsule and renal tubules. Some reactivity against collagen was observed. Antibody activity was found in both IgG and IgM fractions. In immunodeficiency disorders, the autoantibody was found only in patients with selective IgA deficiency.

One hundred adolescents with chest pain were prospectively analyzed to determine the etiology, functional consequences, and illness attributions of patients seen in a general pediatric clinic. The typical patient had frequent pain (63% had two or more episodes weekly) of moderate duration (51% of the pain lasted longer than six minutes) that had been occurring for many months (36% had pain occurring longer than 6 months). Stressful events, such as a death in the family, major illness, an accident, family separations, and school changes occurred in 31% of patients. The most frequently diagnosed condition was musculoskeletal problems (31%) including costochondritis (14%), chest wall syndrome (13%), skeletal trauma (2%), and ribcage anomalies (2%). Hyperventilation accounted for 20% of diagnoses and 5% had breast-related problems. Thirty-nine percent of patients had pain not readily classifiable. Serious underlying illness was a rare cause of chest pain, although several patients had associated organic disease not responsible for their chest pain. More than two thirds of patients restricted physical activities; more than 40% were absent from school. When patients were questioned about their understanding of their illness, 44% were afraid that they were experiencing a heart attack, 12% worried about heart disease, and 12% feared cancer. Chest pain is a prevalent problem that is usually benign but is commonly misunderstood and causes considerable dysfunction and anxiety in adolescents.

Over a 2-year period, the safety and efficacy of a program specifically designed for transtracheal oxygen therapy were evaluated in 100 patients with chronic hypoxemia. The four clinically defined phases of the program included patient orientation, evaluation, and selection (phase I); a new needle-wire guide-dilator transtracheal procedure and stent week (phase II); transtracheal oxygen delivery with an immature tract (phase III); and transtracheal oxygen delivery with a mature tract (phase IV). Sequelae and complications were minor, and patient acceptance was high. As compared with the nasal cannula, the transtracheal catheter was associated with a significant reduction in oxygen flow requirement during both rest and exercise. Adequate oxygenation was maintained over time, and erythrocythemia was alleviated with transtracheal delivery. We conclude that transtracheal oxygenation by this method has a low, acceptable morbidity; it is more efficient than nasal cannula delivery and may be more effective in some patients.

This paper is based on the experience of the author in establishing and directing a program of behavior modification for children and their parents at the New Hampshire Hospital. The focus is on the operant conditioning procedures used with the parents to foster improved relationships with their children and between spouses. Attention was given to the promotion of awareness and praise for productive behaviors and extinction of hostility. Modeling, prompting, shaping, ignoring, and reinforcement principles were followed in parent activities such as TV viewing, individual and group counseling, and controlled visits with children.

The Magnetip* double J type ureteral stent has been used in a wide variety of clinical urological settings. We reviewed the use of the stent in 50 patients. In 45 patients stents were placed in conjunction with extracorporeal shock wave lithotripsy, stone manipulation, obstruction due to pregnancy or malignancy, pyeloplasty and ureteroneocystostomy. In 83 per cent of the attempts the stent was placed successfully. Retrieval with the Magnetriever* was accomplished in 86 per cent of the cases (100 per cent in female and 76 per cent in male patients). Details of stent use are described.

We have presented the case history of a patient with unilateral pyelonephritis and elevated peripheral venous renin, an obvious cause of renal hypertension. However, a complete evaluation revealed pheochromocytoma as the primary cause of the hypertension. It is assumed that the increase in renin is secondary to catecholamine stimulation. Since surgery or diagnostic procedures may be disastrous in a patient with unsuspected pheochromocytoma, we urge all physicians to make a special effort to detect the presence of a tumor in the hypertensive patient.

Jaw claudication accompanies relatively few disorders, but it may be an important presenting feature that heralds serious underlying disease. In temporal arteritis, for example, jaw claudication rather than the classic finding of unilateral lancinating headache may be the distinguishing symptom. In the case reported here, jaw claudication was a prominent symptom for five months in a black woman. Temporomandibular joint disease can produce pain similar to that of jaw claudication, as can rheumatoid arthritis involving the temporomandibular joint in the elderly. Myasthenia gravis closely mimics jaw claudication, and parotid tumors can produce similar pain. Atherosclerotic narrowing of the external carotid artery proximal to the origins of the facial and maxillary branches is a rare cause of jaw claudication. Recognition of the importance of jaw claudication can lead to early identification of the underlying disease and quick initiation of therapy to avoid serious complications.

Morphological and physiological studies were made on chicken cecal isolates of the strictly anaerobic bacterial species Gemmiger formicilis. Structural features (phase-contrast and electron microscopy) of these microorganisms indicate they (i) are highly pleomorphic, (ii) possess a trilaminar cell wall like gram-negative bacteria, (iii) exhibit an unusual growth process characterized by polar swelling (resembling budding bacteria), and (iv) grow into elongated cells when exposed to a subinhibitory concentration of penicillin. The morphological data presented suggest that this species has a rod-shaped structure. These bacteria ferment a variety of sugars to produce formic, butyric, and lactic acids. There appear to be two groups of Gemmiger, one producing primarily lactate and the other producing formate as major fermentation metabolites. Growth of six strains in a basal medium, consisting of Trypticase, minerals, carbohydrate, Na2CO3 buffer, and cysteine as reducing agent, was stimulated by rumen fluid and yeast extract. Volatile fatty acids partially replaced the requirement for rumen fluid with some strains. Single deletions of vitamins (from a defined vitamin mixture) indicated that pantothenate, riboflavin, and thiamine were highly stimulatory to growth of the organism in a medium containing rumen fluid and Trypticase as source of vitamins. Other vitamin requirements were not studied.

Mitochondria contain electron-dense particles, partly composed of an amorphous form of calcium phosphate. We have used electron microscopy from percutaneous renal biopsy material to analyze mitochondrial granulation in the proximal renal tubule of nonuremic and uremic children. Based on a technique of cutting mitochondria from ten electron micrographs per biopsy, counting the granules in each mitochondrion and weighing the paper, we found that mitochondria of nonuremic children averaged 23.7 +/- 1.2 granules/g paper while uremic children had only 11.8 +/- 1.1 granules/g. The number of granules per gram was unrelated to the serum calcium phosphate solubility product. A significant decrease in calcium granulation in uremia can also be produced experimentally in rats. Control rats averaged 14.7 +/- 1.5 granules/g, while rats made uremic by partial nephrectomy had 6.0 +/- 0.7 granules/g. Treatment of uremic rats with a pharmacological dose of vitamin D restored granulation to normal within 24 h. The significant decrease in calcium phosphate granulation in the renal proximal tubule in uremic children and in experimental animals is probably related to the documented loss of 1 alpha-hydroxylation of vitamin D in uremia.