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Biomedical subjects

S M Katz

Publications and source records attributed to S M Katz.

At least 73 records · Page 4Linked to original sources
PubMed1988

Microscopic nephrocalcinosis in cystic fibrosis.

Airway, sweat-duct, and other epithelial cells in patients with cystic fibrosis display abnormal ion transport. To test whether the kidney, the organ most exquisitely adapted for ion transport, has a similar defect, we measured the levels of calcium excretion and searched for microscopic nephrocalcinosis in patients with cystic fibrosis. Thirty-eight specimens of kidney tissue were stained for calcium deposits, and 24-hour levels of urinary calcium excretion were measured in 14 patients and 15 control subjects. Microscopic nephrocalcinosis was observed in 35 of the 38 specimens (92 percent), and hypercalciuria (greater than 182 mg per gram of creatinine) in 5 of the 14 patients (36 percent). Notably, nephrocalcinosis was detected near the time of birth (in six patients under one year old, including two neonates and one stillborn infant), which supports the hypothesis that such renal calcium deposits reflect the genomic defect and are not due to longstanding pulmonary dysfunction, chronic infection, therapeutic agents, or disease progression. None of the patients with hypercalciuria or nephrocalcinosis had clinical evidence of renal dysfunction. The finding of microscopic nephrocalcinosis near the time of birth in patients with cystic fibrosis suggests a primary abnormality of calcium metabolism in the kidney. Studies of the pathophysiologic features of the kidney in cystic fibrosis may elucidate the molecular alterations observed in this disorder.

Adolescent↗
PubMed1988

A self-limited febrile illness produced in guinea pigs associated with oral administration of Legionella pneumophila.

The presumed route of human infection by Legionella pneumophila is inhalation. We investigated possible oral transmission of legionellosis in guinea pigs. Fifty-six guinea pigs (group 1) were given virulent L. pneumophila, serogroup 1, in drinking water. Fifty-nine guinea pigs (group 2) were inoculated with L. pneumophila via gastric intubation. Nineteen guinea pigs (group 3) were given heat-killed L. pneumophila in drinking water. Twenty-four guinea pigs (group 4, positive control) were inoculated intraperitoneally with L. pneumophila. Twenty-seven guinea pigs (group 5, negative control) were either intubated gastrically with phosphate-buffered saline or given drinking water without L. pneumophila. Sixty-six of 115 (57%) of the guinea pigs orally inoculated with viable L. pneumophila (groups 1 and 2) had a temperature greater than or equal to 103 degrees F and 8 of 115 (7%) had diarrhea, compared with 0 of 19 (0%) and 0 of 19 (0%), respectively, in group 3 and 1 of 27 (4%) and 0 of 27 (0%), respectively, in group 5. There were no fatalities in groups 1, 2, 3, and 5 compared with 15 of 24 (63%) in group 4. Groups 1, 2, and 4 consistently showed pneumonitis and splenitis. The pneumonitis of groups 1 and 2 was mild, predominantly interstitial, and mainly composed of macrophages; neither gross nor microscopic evidence of aspiration was seen. In group 1, 4 of 29 (14%) guinea pigs tested seroconverted to L. pneumophila compared with 0 of 7 (0%) in group 3 and 0 of 10 (0%) in group 5. In groups 1 and 2 combined, L. pneumophila was isolated from the lung of 5 of 57 (11%) guinea pigs and spleen of 5 of 47 (11%) guinea pigs compared with 0 of 14 guinea pigs in group 5. We conclude that viable L. pneumophila administered orally produces a self-limited febrile illness in guinea pigs.

Administration, Oral↗
PubMed1988

Transitional epithelial lesions of the ureter in renal transplant rejection.

The spectrum of ureteric lesions of human renal allografts, long attributed exclusively to postsurgical complications such as ischemia, has recently been shown to include the types of rejection seen in the kidney. Since the rejected ureter also exhibits transitional epithelial lesions that may impact on renal and ureteral function, we studied, by light, immunohistochemical, immunofluorescent, and electron microscopic techniques, ureters of 65 irreversibly rejected kidneys. Seven unused cadaver kidneys served as controls. Urothelial lesions, noticed in 57 of 65 ureters (88%), ranged from minimal basal vacuolization to complete sloughing with or without necrosis of the epithelial lining. Epithelial exfoliation was noticed in 31 cases (54.4%), and basal vacuolization, severe enough to produce cleavage of the epithelial junctions and thus create bullae, was noticed in 21 cases (36.8%). Immunofluorescent and immunoperoxidase stains, performed in 16 cases, were all positive for immunoglobulins but yielded varied results ranging from granular to linear staining, particularly in the region of the basal cells and the basement membrane. Electron microscopic findings confirmed the light microscopic alterations. By contrast, control ureters showed no lesions. Urothelial ureteric lesions might impede ureteral functions and result in obstruction or infection, thus compounding the consequences of renal allograft rejection. Moreover, elucidation of the pathophysiology of the process will advance the understanding of various cutaneous and transitional epithelial autoimmune conditions.

Autoimmune Diseases↗
PubMed1988

Hypomagnesemia-induced cardiomyopathy.

Magnesium is the fourth most abundant cation in the body and the second most plentiful intracellularly. Magnesium is crucial to mitochondrial integrity, oxidative phosphorylation, protein synthesis, nucleic acid stability, membrane permeability, and neuro-muscular excitability. In addition, magnesium deficiency induces other electrolyte disturbances including hypocalcemia, hypokalemia, and hypophosphatemia. Because it is not routinely measured, many physicians fail to remember the significance of this element. Reported here is a patient with bulimia who presented with a magnesium deficiency which resulted in her refractory and eventually fatal cardiomyopathy. The cardiac pathophysiology of hypomagnesemia, hypokalemia, hypocalcemia and hypophosphatemia is reviewed and correlated with the clinical and pathological findings.

Adult↗
PubMed1987

Plastic embedding evaluation of Pneumocystis carinii pneumonia in AIDS. Simultaneous demonstration of cyst and sporozoite forms.

To study the possible role of plastic embedding in the surgical pathologic diagnosis of Pneumocystis carinii pneumonia, bronchial biopsy specimens from five patients with AIDS were examined using 0.9 micron thick methacrylate sections stained with silver methenamine borate and counterstained with toluidine blue. This technique was found to be superior to paraffin embedding in the demonstration of the fine structural details of both Pneumocystis and the surrounding lung tissue. This method permitted the simultaneous demonstration of both the cyst wall and intracystic sporozoites of Pneumocystis in biopsy tissue, which had been previously possible only by using electron microscopy. This technique assists in the differentiation of Pneumocystis from other opportunistic agents, and may be useful in estimating the relative numbers of cyst and sporozoite forms of the organism. We recommend that bronchoscopic and open lung biopsies from AIDS patients suspected of having Pneumocystis pneumonia be submitted for plastic embedding and high-resolution light microscopy.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Objective measurement of hypertrophic burn scar: a preliminary study of tonometry and ultrasonography.

Many people are burned each year and subsequently develop hypertrophic burn scars. An objective means for quantitatively measuring scar characteristics would be useful in monitoring resolution of the individual patient's scars as well as in evaluating different treatment protocols. Two methods for quantitative measurement of hypertrophic scars were evaluated in 4 patients at 8 scar sites over a 2-month period. A specially designed tonometer, the cicatrometer, assesses scar firmness and pliability. It is shown to provide a simple noninvasive means for objectively evaluating the progress of scar maturation and therapy. High-resolution ultrasonic scanning is shown to provide an objective, quantitative measurement of hypertrophic scar thickness, which can be compared between patients. This allows for the design of controlled trials comparing different treatment protocols.

Burns↗
PubMed1984

Pleomorphism of Legionella pneumophila.

Legionella pneumophila (Lp), serogroups 1-6, was grown in vitro on a variety of media, in embryonated hens' eggs, and in guinea pigs. The morphology of the microbe was examined by light, immunofluorescent, and electron microscopy (transmission, scanning, negative staining). The configuration of all serogroups examined differed somewhat on agar media, in liquid media, and in vivo. Each serogroup of Lp showed pleomorphic features indistinguishable from the others. Except for filamentous forms, pleomorphism was least conspicuous on agar. By contrast, pleomorphism was most apparent in yeast extract broth, and it was detected by all of the morphologic techniques employed. Bacilli were seen most commonly, but the spectrum of forms was as follows: cocci, coccobacilli (short bacilli), medium bacilli, bacilli with terminal cocci, filamentous forms, and branches. Diplococci, branches, and stalks were only rarely seen, and the latter form was never visualized by immunofluorescence. In tissue samples from infected guinea pigs and embryonated hens' eggs, Lp was typically a short bacillus, but coccoid and coccobacillary forms were seen. Lp is clearly a pleomorphic bacterium, particularly when grown in yeast extract broth. The variety of forms described herein might provide clues to taxonomy, ecologic niche, and physiology of Lp.

Animals↗
PubMed1984

Cilia in the human kidney.

Utilizing transmission electron microscopy we have found multiple cilia with a 9 + 2 microtubular pattern (the same type found in the bronchial tree) in the renal tubules of four adults with the nephrotic syndrome. Each patient had a different pathologic diagnosis: amyloidosis, lipoid nephrosis, membranoproliferative glomerulonephritis, and focal segmental glomerulosclerosis. Previously, multiple renal tubular cilia with 9 + 2 architecture had been reported in patients with Burnett's syndrome, systemic lupus erythematosus, and congenital nephrotic syndrome. Additionally, we found multiple cilia in the metanephric tubules of 4 of 4 human fetuses. Pathologists should be aware that cilia with various microtubular patterns occur in human adult kidneys.

Adult↗
PubMed1983

The relative roles of MHC and non-MHC genes in heart and skin allograft survival.

Although the role of the major histocompatibility complex (MHC) of the rat (RT1) in graft rejection has been established, the role of non-RT1 genes is not well understood. To investigate the influence of MHC and non-MHC genes in graft rejection, various combinations of congenic and inbred strains of rats were used as donors and recipients of skin grafts and perfused abdominal heart grafts. In addition, hemagglutinating and cytotoxic antibody responses were evaluated to assess loci that were serologically active in transplantation. Our results demonstrate that: (1) RT1 antigens are the most important determinant in heart and skin rejection; (2) antigens controlled by non-MHC genes also play a major role in rejection because they cause disparate heart grafts to be rejected by day 18 and skin grafts by day 26; (3) RT2 cell antigens alone do not cause graft rejection; and (4) allogeneic differences at the RT1, RT2, RT3, and RT6 loci elicit an antibody response in heart transplantation.

Animals↗