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Biomedical subjects

M A Weiss

Publications and source records attributed to M A Weiss.

At least 163 records · Page 9Linked to original sources

Recurrence of diabetic nodular glomerulosclerosis in a renal transplant.

A 36-year-old woman with a 26-year history of insulin-dependent diabetes mellitus developed chronic renal failure in 1974 and was started on dialysis. She received a kidney transplant from her HLA-identical brother. Her HLA typing showed the following antigens: A1, A28, B8, B12 (44), BW4, BW6 DR3, and DR4. Nephrectomy performed prior to transplantation showed advanced diffuse diabetic glomerulosclerosis. Her postoperative course was relatively uncomplicated, but within the next seven years she gradually developed symptoms of deteriorating renal function and hypertension. Two years later, a renal arteriogram showed 90% stenosis of the main renal artery. Biopsy of the kidney was obtained during surgical repair of this lesion and showed diffuse nodular diabetic glomerulosclerosis. Since the B8/DR3 form of diabetes is reported to have a predilection for diabetic microangiopathy and vascular complications, we are speculating that the patient's antigenic composition might have enhanced the recurrence of the diabetic lesions in the transplanted kidney.

Adult↗

Reactive airways dysfunction syndrome (RADS). Persistent asthma syndrome after high level irritant exposures.

Ten individuals developed an asthma-like illness after a single exposure to high levels of an irritating vapor, fume, or smoke. In most instances, the high level exposure was the result of an accident occurring in the workplace or a situation where there was poor ventilation and limited air exchange in the area. In all cases, symptoms developed within a few hours and often minutes after exposure. We have designated the illness as reactive airway dysfunction syndrome (RADS) because a consistent physiologic accompaniment was airways hyperreactivity. When tested, all subjects showed positive methacholine challenge tests. No documented preexisting respiratory illness was identified nor did subjects relate past respiratory complaints. In two subjects, atopy was documented, but in all others, no evidence of allergy was identified. In the majority of the cases, there was persistence of respiratory symptoms and continuation of airways hyperreactivity for more than one year and often several years after the incident. The incriminated etiologic agent varied, but all shared a common characteristic of being irritant in nature. In two cases, bronchial biopsy specimens were available, and an airways inflammatory response was noted. This investigation suggests acute high level, uncontrolled irritant exposures may cause an asthma-like syndrome in some individuals which is different from typical occupational asthma. It can lead to long-term sequelae and chronic airways disease. Nonimmunologic mechanisms seem operative in the pathogenesis of this syndrome.

Adult↗

Thrombosis in systemic lupus erythematosus. Relation to the presence of circulating anticoagulants.

In an earlier report on the kidney in systemic lupus erythematosus (SLE), we described a subset of patients with circulating anticoagulants; many had glomerular and arteriolar thrombosis in the absence of necrosis and subendothelial deposits. The present study extends these observations to a larger group of patients with SLE and a circulating anticoagulant, and compares its findings with those in patients with SLE without evidence of an anticoagulant. It demonstrates (1) a higher prevalence of clinically recognizable thrombotic events in the venous and arterial circulations in patients with SLE and a detectable anticoagulant; (2) a probable shortening in life span; (3) a higher prevalence of glomerular thrombi; (4) elevated levels of factor VIII antigen and von Willebrand factor; and (5) significantly lower platelet counts and decreased in vitro platelet aggregation in response to adenosine diphosphate, epinephrine, and collagen. Since prednisone treatment often results in improvement or disappearance of a prolonged partial thromboplastin time, the test most commonly used for screening of a circulating anticoagulant, we suggest that the prevalence of this abnormality may be underestimated in patients with SLE.

Adolescent↗

Lupus nephritis with thrombosis and abnormal fibrinolysis: effect of ancrod.

Recent evidence demonstrates that coagulation plays a role in mediating glomerular damage in patients with systemic lupus erythematosus and diffuse proliferative glomerulonephritis. Because of its beneficial effect in experimental glomerulonephritis, we treated patients with systemic lupus erythematosus and diffuse proliferative glomerulonephritis with ancrod, a drug known to lower fibrinogen levels and thought to activate fibrinolysis. Our patients had unusually severe renal disease; renal function was deteriorating in many. Before ancrod, vascular plasminogen activator levels were low, and levels of an inhibitor of plasminogen activation were elevated. Some patients had elevated plasmin inhibitor levels. Results were considered in two groups. In 13 patients characterized as fibrinolysis responders, the low vascular plasminogen activator and increased plasminogen activation inhibitor levels normalized. After ancrod, striking resolution of microvascular thrombosis occurred, which was associated with some improvement in renal function and blood pressure control. In five patients characterized as fibrinolysis nonresponders and who also had an elevated plasmin inhibitor (alpha 2-antiplasmin) level, normalization of fibrinolysis did not occur. There was little change in microvascular thrombosis, renal function, or blood pressure control in the fibrinolysis nonresponders. These preliminary observations demonstrate a disorder of fibrinolysis in patients with systemic lupus erythematosus with microvascular thrombi in the kidney. Ancrod therapy reverses this disorder rapidly in patients with a normal level of plasmin inhibitor and may lead to repair of glomerular damage.

Adolescent↗

Reactive airways dysfunction syndrome. Case reports of persistent airways hyperreactivity following high-level irritant exposures.

Two individuals developed an asthma-like illness after a single exposure to high levels of an irritating aerosol, vapor, fume, or smoke. Symptoms developed within a few hours. A consistent physiologic accompaniment was airways hyperreactivity, with the two subjects showing positive methacholine challenge tests. No documented preexisting respiratory illness was identified, nor did subjects relate past respiratory complaints. Respiratory symptoms and airways hyperreactivity persisted for at least four years after the incident. The incriminated etiologic agents all shared a common characteristic of being irritant in nature. Bronchial biopsy specimens showed an airways inflammatory response. This report suggests that acute high-level irritant exposures may produce an asthma-like syndrome in some individuals, with long-term sequelae and chronic airways disease. Nonimmunologic mechanisms seems to be operative in the pathogenesis of this syndrome.

Adult↗

Amino-terminal arm of the lambda repressor: a 1H NMR study.

The N-terminal arm of the lambda repressor is shown to be flexible in solution by one- and two-dimensional 1H NMR methods. In particular, the relaxation of Thr-2 is largely independent of macromolecular tumbling. The conformation of the operator-binding domain is not affected by the removal of the first three residues nor by a point mutation, Lys-4----Gln. These results support a proposed model of the lambda repressor-operator complex in which the N-terminal arm of the repressor is assumed to be flexible and to wrap around the operator double helix.

DNA-Binding Proteins↗

1H-NMR study of the lambda operator site OL1: assignment of the imino and adenine H2 resonances.

One- and two-dimensional proton NMR methods are being used to study the synthetic lambda operator site O-L1, a 17 base-pair DNA duplex recognized by lambda repressor and Cro protein. The complete assignment of the 17 imino protons, which participate in Watson-Crick hydrogen bonding, and of the eight adenine H2 protons, which lie in the minor groove of the double helix, is presented.

Adenine↗

Secondary renal osteogenic sarcoma 14 years after primary therapy.

We excised a left renal osteogenic sarcoma 14 years after curative therapy for a primary tumor of the left ulna and 2 years after resecting a solitary pulmonary metastasis. This large renal neoplasm was recognized because it concentrated abnormally large amounts of technetium during a radionuclide bone scan.

Adult↗

Renal biopsy findings in Wegener's granulomatosis: segmental necrotizing glomerulonephritis with glomerular thrombosis.

The clinicopathologic features of 14 patients with documented Wegener's granulomatosis (WG), with a detailed analysis of renal biopsy findings, are presented. The characteristic renal lesion found in all initial and in three of eight follow-up biopsies was segmental necrotizing glomerulonephritis (SNGN). The SNGN was generally focal and involved more than 60 per cent of the glomeruli in only two specimens. Light microscopic evidence of glomerular thrombosis, with or without necrosis, was found in 60 per cent of the biopsies. By immunofluorescence fibrin was demonstrated in 54 per cent of the biopsy specimens with "acute" SNGN, while 36 per cent of the specimens lacked both IgG and C3. Electron microscopy showed fibrin(oid) deposition with variable platelet activation associated with mesangionecrosis (two specimens) and peripheral glomerular basement membrane fragmentation/dissolution (three specimens). Rare discrete intramembranous (four specimens) and mesangial/subendothelial (one specimen) dense deposits were identified, but these deposits were associated with necrosis in only two biopsies. These findings fail to demonstrate an immune complex pathogenesis for the SNGN and suggest that glomerular thrombosis and necrosis are the primary findings in WG.

Adult↗

Dynamic filtering by two-dimensional 1H NMR with application to phage lambda repressor.

Flexible regions of proteins play an important role in catalysis, ligand binding, and macromolecular interactions. Because of its enhanced sensitivity to motional narrowing, two-dimensional coupling constant J-correlated 1H NMR may be used to observe these regions selectively. Dynamic filtering is an intrinsic feature of this experiment because cross-peak amplitude decays rapidly as linewidths approach the coupling constant. We demonstrate here the flexibility of the NH2-terminal arm of phage lambda repressor, which is thought to wrap around the double helix in the repressor-operator complex. The assignment of arm resonances is made possible by the construction of mutant repressor genes containing successive NH2-terminal deletions.

Bacteriophage lambda↗

Benign lymphocytic angiitis and granulomatosis: a case report with evidence of an autoimmune etiology.

Benign lymphocytic angiitis and granulomatosis (BLAG) is characterized by dense benign-appearing infiltrates of mature lymphocytes, plasma cells, and histiocytes within the pulmonary parenchyma and vasculature. The disorder typically is restricted to the lungs and has a good prognosis. The authors report a patient with BLAG and involvement of lung, kidney, and prostate. This is the first report of prominent systemic distribution in this disease. Another unique feature of this case was the presence of serum antinuclear antibodies and evidence of immune complex deposition in both lung and kidney, suggesting an underlying autoimmune disorder. An association of this entity with lymphomatoid granulomatosis (LG) has been suggested, and the prominent genitourinary disease in this patient may be indicative of a transitional stage leading to LG. An autoimmune state may be the underlying stimulus for the development of BLAG and LG.

Antibodies, Antinuclear↗

Necrotizing sarcoid granulomatosis with suppurative features.

Necrotizing sarcoid granulomatosis has become a well-defined entity within the spectrum of disorders classified as pulmonary granulomatosis with angiitis. It is characterized clinically by disease generally restricted to the chest, steroid sensitivity, and a good prognosis. Pathologically, confluent granulomas, vasculitis, and bland necrosis are seen. The authors report a patient initially presenting with the typical clinical and pathologic features of necrotizing sarcoid granulomatosis who, on subsequent recurrence, demonstrated a suppurative character to the necrosis. This feature has not been reported previously, and its recognition will allow more cases to be diagnosed correctly. Serum angiotensin converting enzyme (ACE) was not elevated, and ACE could not be demonstrated in tissue from the lung biopsy obtained during recurrence of disease. This further suggests significant differences between this entity and sarcoid.

Adult↗

Hyperfunctioning cystic parathyroid glands: CT and sonographic findings.

Four functioning cystic parathyroid glands were evaluated with computed tomography (CT) and sonography in four patients, only one of whom had prior surgery. Sonography demonstrated solid lesions of decreased echogenicity with fluid-filled cavities near the lower thyroid poles or in the posterosuperior mediastinum. On CT the cystic parts of the lesions were of low attenuation (1-44 H), often with a well defined wall that was better demonstrated after intravenous contrast administration. Fine-needle aspiration biopsy of two of the cystic parathyroids revealed elevated parathyroid hormone levels. These lesions probably represent degenerating adenomas rather than true parathyroid cysts. While the CT and sonographic findings are nonspecific, the diagnosis of a cystic parathyroid should be entertained when a fluid-filled lesion is encountered in the neck of a patient with or without hypercalcemia. The diagnosis may be confirmed by assay of parathyroid hormone from the fluid aspirate.

Adenoma↗

Expression of normal and tumor-associated antigens in human breast carcinoma.

The expression of six cytoplasmic/membrane antigens (beta 2-microglobulin, HLA, HLA-DR, carcinoembryonic antigen, and two breast tumor-associated antigens (TAAs), B6.2 and B72.3) was investigated in serial sections of 28 human breast carcinomas using monoclonal antibodies and the avidin-biotin complex immunoperoxidase technique. The frequency of expression and linkage between these antigens was determined, and antigenic expression was related to patient age, morphologic differentiation, cytologic grade, and estrogen receptor/progesterone receptor content of the tumor. The expression of beta 2-microglobulin and HLA correlated with morphologic differentiation, well-differentiated and moderately well-differentiated tumors expressing these antigens more often than poorly differentiated tumors. Expression of the TAAs, however, was not related to differentiation. There was no linkage between beta 2-microglobulin/HLA and the TAAs. Carcinoembryonic antigen was found to be linked to the TAA, B6.2. Expression of the TAA, B72.3, correlated with patient age. Eighty percent (23 of 28) of the tumors were positive for carcinoembryonic antigen or at least one of the TAAs. The estrogen receptor/progesterone receptor status of the tumor was not statistically related to the expression of any of the antigens studied. Analysis of tumor antigen profiles may provide important information relevant to prognosis, therapy, and early detection of cancer, as well as insights into the nature of the neoplastic process.

Adult↗

Ancrod in systemic lupus erythematosus with thrombosis. Clinical and fibrinolysis effects.

A patient with systemic lupus erythematosus had severe hypertension, rapidly worsening renal failure, and multiple successive thrombotic cerebrovascular and retinal lesions develop. In a kidney biopsy specimen luminal thrombi were demonstrated in arteries and arterioles, without vasculitic or inflammatory changes. The patient's plasma was markedly deficient in both prostacyclin stimulating factor (PSF) and vascular plasminogen activator (VPA), and also contained a potent inhibitor of in vitro urokinase-induced fibrinolysis. Treatment with ancrod resulted in striking reversal of the progressive renal damage and clinical recovery from the thrombotic cerebrovascular and retinal lesions. This clinical improvement was associated with improved renal histologic appearance, correction of the PSF and VPA deficiencies, and disappearance of the urokinase inhibitor. Possible mechanisms of action of ancrod are discussed.

Acute Kidney Injury↗

Membranous glomerulopathy following kidney transplantation. Association with renal vein thrombosis in two of nine cases.

The association of renal vein thrombosis and membranous glomerulopathy in native kidneys has been well documented. However, this association has only occasionally been described following renal transplantation. A review of 693 renal transplant recipients revealed 77 (11%) in whom persistent, heavy proteinuria (greater than 2 g/24 hr) developed. Renal histology was available in all 77 patients. A diagnosis of membranous glomerulopathy was made in 7 patients. Two further cases were added on the basis of biopsy findings--1 patient had a protein excretion of 1.7 g/24 hr, the other had microscopic hematuria and red cell casts in the urine. Renal venography was performed in 4 cases. The decision to perform venography was based on clinical criteria (thrombophlebitis or marked edema of the leg on the side of the allograft), and/or histological criteria (associated interstitial edema and venous congestion). Renal vein thrombosis was present in 2 patients. Three of the 9 patients had membranous glomerulopathy as the cause of their end-stage renal disease; 2 of these patients had received kidneys from living-related donors. Four of the patients were classified as having de novo membranous glomerulopathy on the basis of having a different cause for their end-stage renal disease. Two patients were classified as having unspecified membranous glomerulopathy; both of these patients had had chronic glomerulonephritis, but there was lack of characterization of the original glomerular disease. Seven of the 9 patients continued to have stable allograft function 1-12 months after the diagnosis of membranous glomerulopathy was made in the renal allograft. The remaining 2 patients both had associated renal vein thrombosis; 1 had progressive deterioration of renal function and returned to dialysis 24 months after the diagnosis of membranous glomerulopathy had been made, while the other died of unrelated causes 27 months after the diagnosis had been made.

Adult↗