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S M Bonsib

Publications and source records attributed to S M Bonsib.

At least 55 records · Page 3Linked to original sources
PubMed1988

Glomerular basement membrane necrosis and crescent organization.

In order to reveal structural damage to the glomerular basement membranes occurring in crescentic glomerulonephritis and the subsequent connective tissue organization of the crescent, 14 kidney biopsies were treated with detergents to remove cellular components and the tissue remaining examined by transmission (TEM) and scanning (SEM) electron microscopy. The fourteen biopsies were divided into two groups for analysis. Group I (7 cases) contained necrotizing lesions and cellular crescents. Acellular TEM (ATEM) revealed widespread lysis of mesangial matrix, while acellular SEM (ASEM) of five cases revealed three general patterns of GBM necrosis. Group II (7 cases) contained fibrocellular and fibrosis crescents. ATEM and ASEM revealed that collagen fibers initially form along fibrin fibrils and eventually result in formation of lacunar spaces occupied by cells of the crescent. Fibrous crescents were associated with prominent glomerular tuft distortion and entrapment of normal capillary loops. Continuity between interstitial space, matrix of crescent and mesangium were often observed. These observations suggest that lysis of mesangial matrix is extensive and precedes GBM lysis while the pattern of GBM damage fits best with local release of lytic factors. Furthermore, the architectural distortion and continuity which develops between normally segregated compartments (mesangial-interstitial) indicate that both the initial necrosis and the reparative response to injury, contribute substantially to overall nephron dysfunction.

Basement Membrane↗
PubMed1988

Development of fetal lamb lung and kidney in obstructive uropathy: a preliminary report.

Oligohydramnios, whatever the cause, results in lungs that are 'hypoplastic' or at least smaller than normal. The fine structure in such lungs has not been reported previously. Three fetal lambs had both ureters ligated at 60, 72 and 58 days of gestation. They were sacrificed at 117, 143 and 142 days of gestation. The lungs were fixed by tracheal perfusion at 15 mm Hg. Individual lobar volumes were determined, and the lungs were sampled for electron microscopy. Total lung volumes for 2 of the lambs were very close to those previously reported for lungs of equivalent gestation with diaphragmatic hernia. The third lamb had a twin that had been unrecognised at the time of the original procedure. This lamb's lung volumes were normal. The morphological appearances of the lungs at the electron microscopy level are not normal but dramatically different from those previously reported in lambs with diaphragmatic hernia, phrenic nerve avulsion, and fetal tracheostomy. The lungs of the lamb with bilateral ureteric ligation and a normal twin were essentially normal. These preliminary findings point to the need for more studies of lung structure in oligohydramnios/obstructive uropathy models. However, the normal lungs in a lamb with grossly dysplastic kidneys and a normal twin argue against any important renal trophic factor in lung development in the fetal lamb. An interesting sidelight to this investigation was the unequivocal demonstration that early ureteric ligation results in true renal dysplasia in the fetal lamb. The kidneys of the lamb sacrificed at 117 days were smaller than normal and grossly dysplastic. The kidneys of the lambs that underwent ureteric ligation at 60 and 72 days were structurally different, with the ureters ligated at 60 days being small and dysplastic, while those with the ureters ligated at 72 days were larger and appeared almost polycystic.

Animals↗
PubMed1987

Sarcomatoid renal tumors. Clinicopathologic correlation of three cases.

The clinical, light and ultrastructural features of three renal neoplasms demonstrating a sarcomatous appearance on light microscopic examination are reported. At the time of radical nephrectomy, all three tumors displayed aggressive features with capsular invasion and either metastases or invasion of adjacent organs. Ultrastructural examination revealed epithelial features in a pure spindle cell tumor and in a malignant fibrous histiocytoma-like tumor (sarcomatoid renal carcinoma) and smooth muscle differentiation (leiomyosarcoma) in a lesion showing features of malignant fibrous histiocytoma. All three patients died from 1 to 9 months after nephrectomy. Renal tumors with a sarcomatous histologic appearance are aggressive neoplasms that cannot be classified accurately solely by employing light microscopic criteria.

Adult↗
PubMed1987

Coexistent Wegener's granulomatosis and anti-glomerular basement membrane disease.

Wegener's granulomatosis and Goodpasture's syndrome represent two major causes of a pulmonary-renal syndrome. We describe the clinical course and morphologic features of a patient in whom pulmonary manifestations of Wegener's granulomatosis developed and were followed six months later by anti-glomerular basement membrane disease. Although we regard this as a unique and probably fortuitous association, a genetic predisposition or a secondary form of anti-GBM disease cannot be excluded.

Aged↗
PubMed1986

Giant cell tumors of synovium (Pigmented villonodular synovitis) involving the vertebral column.

Giant cell tumors of synovium (pigmented villonodular synovitis) involving the vertebral column recently have been seen in two women: the third and fourth cases to be reported in the English-language literature. Unlike the previously reported cases, both these tumors grew outside the dura and produced symptoms of spinal cord compression. The first case involved lumbar vertebrae 5 and 6; the second, lumbar vertebrae 2 and 3. Even though initial resection of both tumors was incomplete, the patients improved postoperatively. One tumor was known to be unresectable at the time of surgery. In the other patient, a recurrence of symptoms required second and third resections 4 and 8 months after the first, respectively. Although synovial giant cell tumors rarely metastasize, the rate of local recurrence is high, especially if excision is incomplete. For this reason, close follow-up of patients with lesions in the spinal column is indicated. Increased physician awareness that synovial giant cell tumors can occur in the spine will help to ensure that these tumors are not misdiagnosed in this location.

Adult↗
PubMed1986

Two types of collecting duct mitochondria-rich (intercalated) cells: lectin and band 3 cytochemistry.

Anion exchange plays an important role in renal ion transport and acidification. To further understand the molecular nature of renal epithelial anion exchange, we used a monoclonal antibody to the membrane domain (52 kDa) of human erythrocyte band 3 protein to immunocytochemically search for this polypeptide in the rabbit kidney. In cryostat sections, a subpopulation of cells in the cortical and outer medullary collecting tubules showed immunoreactivity; labeling was restricted to the basolateral membrane. Proximal tubules and thick and thin limbs of Henle showed no immunoreactivity. Approximately 11% of cells in the cortical, but 43% of cells in the medullary, collecting tubule were positive for band 3. To determine the type of cells that were band 3 positive, mitochondria-rich (intercalated) cells were identified by their positive histochemical staining for succinic dehydrogenase activity and by their ability to bind peanut lectin at the apical membrane. In the cortical collecting tubule, the majority of mitochondria-rich cells bound peanut lectin but were band 3 negative; the remainder were band 3 positive but lectin negative. This distribution was reversed in the inner stripe of the outer medulla: all mitochondria-rich cells were band 3 positive and lectin negative. Thus mitochondria-rich cells are of at least two types, each of which has a distinct axial distribution pattern. Given available information about in vitro HCO3 transport properties of rabbit collecting tubules, it is likely that the lectin-positive, band 3-negative mitochondria-rich cells secrete HCO3, whereas the lectin-negative, band 3-positive cells reabsorb HCO3 (secrete H).

Animals↗
PubMed1986

In utero bladder diversion--problems with patient selection.

Based upon the concept that an obstruction-maldevelopment sequence is reversible after diversion, it has been suggested that the fetus with a bladder outlet obstruction is a potential candidate for in utero intervention. We report an infant who had both renal and pulmonary dysplasia at birth despite a technically successful diversion at 22 weeks' gestation. The poor outcome suggests that the organ damage either occurs so early that it precludes corrective surgery, or that the maldevelopment is not the result of obstruction, but rather a primary mesodermal defect.

Abdomen↗
PubMed1986

Acellular scanning electron microscopy of spicular renal amyloidosis.

Two human renal biopsies containing glomerular amyloid deposits organized into spicular formations (spicular amyloid) were studied by scanning electron microscopy following removal of the cellular components (acellular SEM). Following SEM studies, portions of the same acellular tissue were embedded in paraffin and plastic for light microscopy and transmission electron microscopy, respectively. Spicular deposits by acellular SEM appear as tapering conical formations interconnected by a delicate branching network of fibrils, which imparts a higher degree of organization than previously appreciated by two-dimensional LM and TEM. Silver stains of paraffin- and plastic-embedded acellular tissue showed persistence of argyrophilia in spicular deposits, while acellular TEM showed that the spicules appeared comprised "purely" of amyloid fibrils without visible contaminating material. We conclude that the argyrophilia of spicular amyloid is an inherent feature of the parallel organization of fibrils rather than a result of incorporation of glomerular basement membrane or cell components and that spicular amyloid deposits have a higher degree of organization than is apparent by two-dimensional studies.

Amyloid↗
PubMed1986

Argyria: microanalytic-morphologic correlation using paraffin-embedded tissue.

Scanning electron microscopes, which have energy dispersive spectroscopy (x-ray microanalysis) capability, can provide accurate identification of the composition of inorganic deposits in tissue. We report a case of florid argyria in which the same deparaffinized 4-micron sections were sequentially examined by light microscopy, scanning electron microscopy, backscattered electron imaging, and x-ray microanalysis to confirm the clinical impression of argyria. We recommend the use of x-ray microanalysis of paraffin-embedded tissue as a simple, rapid and inexpensive means of precise identification of inorganic deposits of heavy elements in tissue sections.

Administration, Intranasal↗
PubMed1985

Recurrent thrombotic microangiopathy in a renal allograft. Case report and review of the literature.

Thrombotic microangiopathy in a renal allograft may either reflect a recurrence of the patient's original disease, i.e., thrombotic thrombocytopenic purpura, hemolytic-uremic syndrome, or more commonly may be a manifestation of allograft rejection. This report describes a patient in whom irreversible renal failure developed during thrombotic thrombocytopenic purpura. Two years later while her condition was in clinical remission, she received a 2 DR-matched cadaveric allograft. Nineteen days following transplantation, thrombotic microangiopathy developed in the graft with eventual loss of allograft function despite vigorous plasmapheresis therapy. Multiple factors in addition to possible recurrent disease that may have contributed to this event were identified. The literature on thrombotic microangiopathy and renal transplantation is reviewed.

Adult↗
PubMed1985

Segmental subepithelial deposits in primary glomerulonephritis: scanning electron microscopic examination of acellular glomeruli.

More accurate perception of the structural alterations in glomerular basement membrane (GBM) produced by subepithelial immune complex deposits is possible with a recently adapted technique that uses scanning electron microscopy of acellular material. With this procedure frozen tissue is treated sequentially by osmotic lysis, detergents, and DNase to solubilize both cellular components and immune complex deposits. Four patients with glomerulonephritis (acute postinfectious glomerulonephritis [one patient], segmental membranous glomerulonephritis [two patients], membranoproliferative glomerulonephritis, type III [one patient]) in whom segmental subepithelial deposits were found were studied by this technique; the resulting observations were correlated with the results of routine morphologic studies and a previous study of minimal change disease and diffuse membranous glomerulonephritis. Four types of structural alterations of the subepithelial GBM surface were observed. The differences in lesions observed in the various forms of glomerulonephritis are believed to be related to temporal, quantitative, and qualitative differences in immune complex-mediated glomerular injury.

Basement Membrane↗
PubMed1985

Scanning electron microscopy of acellular glomeruli in nephrotic syndrome.

All cellular elements were extracted from portions of 13 renal biopsies performed for nephrotic syndrome and the acellular glomerular basement membrane (GBM) examined by scanning electron microscopy (SEM). Five biopsy specimens did not contain subepithelial deposits by light microscopy (LM), immunofluorescence (IF), and transmission electron microscopy (TEM). SEM of the acellular GBM showed a uniform slightly granular surface identical to that previously reported for normal human GBM. Eight biopsy specimens contained subepithelial deposits by LM, IF, and TEM. SEM showed complete extraction of deposits and a spectrum of clearly visualized diffuse GBM alterations in response to subepithelial deposits. Shallow pits or indentations of the GBM were noted in two cases stage I MGN which correlated with numerous "pinholes" visualized by LM in tangential sections of the GBM on silver stain. A complex reticular pattern of GBM elaboration was observed in cases of stage II MGN corresponding to "spikes" visualized by LM on silver stain. SEM of glomeruli following cell extraction permits the first direct three-dimensional visualization of the GBM alterations occurring in various stages of subepithelial immune complex formation.

Adult↗
PubMed1985

Ask-Upmark kidney with contralateral renal artery fibromuscular dysplasia.

A case of Ask-Upmark kidney with coexistent contralateral renal artery fibromuscular dysplasia is presented with detailed light and electron microscopic findings. Both lesions are known to produce renin-mediated hypertension which was corrected in this patient by nephrectomy and contralateral renal artery bypass. Ask-Upmark kidney is briefly reviewed.

Adult↗
PubMed1985

Glomerular basement membrane discontinuities. Scanning electron microscopic study of acellular glomeruli.

Glomerulonephritides which develop necrotizing and crescentic lesions usually have glomerular basement membrane (GBM) disruptions when carefully examined by light microscopy or transmission electron microscopy. Despite numerous excellent and detailed ultrastructural investigations of GBM discontinuities, a complete appreciation of their actual number, appearance, and distribution within a glomerulus has been difficult to achieve by reconstruction of two-dimensional light or transmission electron microscopic images. Selective removal of podocytes by a sequence of lytic and solubilization procedures has been developed which exposes any structural alteration of the GBM to direct examination by scanning electron microscopy. A case of idiopathic, immune-complex-negative, focal-segmental necrotizing glomerulonephritis has been studied by this technique, permitting three-dimensional visualization of the GBM defects which result in free communication between the vascular and urinary spaces. These disruptions were distinctive by their frequency within an affected lobule, variable size, and sharply demarcated edges. Application of this technique to human renal biopsies is capable of enhancing our understanding of the morphologic alterations occurring in human glomerulonephritis.

Basement Membrane↗
PubMed1984

Urological manifestations of patients with visceral myopathy.

Of 10 patients with familial or nonfamilial visceral myopathy studied for urological manifestations only 3 had symptoms of urinary retention. Excretory urography revealed megacystis in all 3 symptomatic patients, while the 7 asymptomatic patients had normal-sized bladders. Cystometrograms performed in 4 asymptomatic patients also were normal. Bladder tissue from 5 patients was studied. Of 3 autopsy cystectomy specimens 2 were dilated severely and thin-walled without trabeculations or diverticula suggestive of mechanical obstruction. Microscopic sections showed segmental intrafascicular fibrosis in 4 patients, which was associated with elastosis in 3. Electron microscopy of leiomyocytes in abnormal fascicles revealed myofilament disorganization, lipid accumulation and increased numbers of cytoplasmic organelles. We conclude that pathological changes in the bladder occur commonly but urinary symptoms occur in less than half of the patients with visceral myopathy available for study. An abnormal excretory urogram was seen in only patients who had symptoms suggestive of lower urinary tract dysfunction.

Adolescent↗
PubMed1984

Scanning electron microscopy of acellular glomeruli in human glomerulonephritis: application of a technique.

Scanning electron microscopy (SEM) has been employed in studies of human and experimental glomerulonephritis (GN), a major contribution being the elucidation of podocyte morphology and the process of podocyte foot process retraction in proteinuric conditions. Application of SEM in GN has been limited however by an emphasis on cell surface alterations while the site of major disease processes, the glomerular basement membrane, has remained hidden from view. A previously reported technique for the preparation of acellular glomeruli from fresh tissue has been adapted for use on frozen human renal biopsies. One case of minimal change disease (MCD) and one case of membranous glomerulonephritis (MGN) have been studied. The acellular glomerular basement membrane of MCD has a lightly textured or granular surface whereas in MGN a striking reticular network of basement membrane has formed perpendicular to the native basement membrane. The immune complexes have been removed. This technique provides a graphic visualization of GBM alterations occurring in glomerulonephritis and is applicable to the study of human as well as experimental model of glomerulonephritis.

Basement Membrane↗