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J Passwell

Publications and source records attributed to J Passwell.

18 recordsLinked to original sources
PubMed1989

Tissue-specific initiation of murine complement factor B mRNA transcription.

Factor B (Bf) gene expression is regulated independently in hepatic and extrahepatic tissues. In studying murine factor B expression, we found two mature mRNA species for Bf in kidney and intestine (2.7 and 2.4 kb) but in other tissues, including liver, lung, spleen, heart, brain, and skeletal muscle, only a single Bf transcript (2.4 kb) was observed. These two Bf transcripts in kidney or intestine are identical in structure except for a 300 bp 5' extension found in the 2.7-kb mRNA. The long Bf transcript originates from a tissue-specific alternative site of transcriptional initiation upstream of the initiation site for the 2.4-kb mRNA, as determined by primer extension and nuclease protection assays. The upstream initiation site lacks a typical promoter motif and is only 80 bp downstream from the terminus of the murine C2 gene. After stimulation in vivo with endotoxin, only the 2.4-kb mRNA increases in kidney indicating independent regulation of the two Bf transcripts. The differences in 5' untranslated region generated in these two Bf mRNA species may affect local concentrations of factor B protein in kidney and intestine by mechanisms depending on differential translation rates or stability of mRNA.

Acute-Phase Reaction↗
PubMed1988

Local extrahepatic expression of complement genes C3, factor B, C2, and C4 is increased in murine lupus nephritis.

Systemic lupus erythematosus (SLE) is associated with the presence of complement proteins and immune complexes in affected organs. Since complement proteins are synthesized in hepatic and extrahepatic sites, we studied a murine model of SLE to ascertain the relative importance of local and humoral (liver) synthesis of complement. C3, C4, and C2 mRNA increase in kidney coincident with the development of nephritis in the MRL lpr/lpr mouse, a strain that spontaneously develops SLE. Two factor B messenger RNA transcripts are expressed in kidney and intestine; SLE nephritis is associated with decrease in the long factor B mRNA and increase in the short form. Increased local synthesis of C3 and B protein and a concomitant glomerular and renal interstitial macrophage infiltrate paralleled the increase in mRNA content in the (lpr/lpr) mice. In addition to kidney, an increase in C3, C4, C2 and factor B mRNA was noted in the lung, heart and intestine and to a lesser extent in liver of (lpr/lpr) in comparison to the MRL (+/+) animals. These results suggest that in SLE local expression of complement genes plays a role in the pathogenesis of chronic glomerulonephritis and in the autoimmune arteritis of other organs.

Animals↗
PubMed1987

The varied clinical and laboratory manifestations of type II Gaucher's disease.

An infant of Arab extraction with the Type II form of Gaucher's disease is described. His clinical presentation was unusual because in addition to the extensive neurological involvement and marked hepatosplenomegaly a severe congestive cardiomyopathy and renal tubular dysfunction were present. In addition, marked hypergammaglobulinemia and raised serum angiotensin converting enzyme levels were found. It is suggested that these varied manifestations may be ascribed to the consequences of glucocerebroside deposition within the macrophages of the reticuloendothelial system.

Cardiomyopathy, Dilated↗
PubMed1987

Effects of the components of breast milk on mucosal enzyme activity of the newborn small intestine.

The effects of the aqueous phase of human breast milk on the disaccharidase activity of newborn rabbit small intestinal mucosal explants were studied in vitro culture. These explants continuously synthesized protein and normal morphology was maintained for the duration of the cultures. Addition of the aqueous phase resulted in significant increase of lactase (p less than 0.001) and maltase (p less than 0.01) concentrations in these organ cultures. This effect was dose dependent and was observed whether the organ biopsies were derived from fed or starved newborn rabbits. Further purification of the aqueous phase showed that the active ingredient exerting these effects was lactose. These studies suggest that lactose may have an important function in stabilization of newborn intestinal disaccharidase enzymes.

Animals↗
PubMed1985

Human monocytes infected with Leishmania amastigotes enhance lymphocyte proliferation.

Human monocytes were infected in vitro with Leishmania tropica major (L. major) promastigotes which transformed to intracellular amastigotes. A spontaneous increase in lymphocyte proliferation occurred in mononuclear cell cultures where the monocytes had been infected with L. major organisms. In addition, an apparent additive effect of lymphocyte proliferation was seen in cultures infected with L. major following phytohaemagglutinin stimulation. This effect was apparent after 3 days in culture and the amount of increase in response was dependent on the number of monocytes in the culture. The effect was also dependent on the number of parasites ingested by the monocytes. The presence of monocytes was essential for this effect, as no enhancement was observed with supernatants from infected cells. This enhanced effect of lymphocyte proliferation was observed predominantly in the B lymphocyte subpopulation. These findings may be of relevance in the immunopathogenesis of Leishmania infections.

B-Lymphocytes↗
PubMed1979

Enzyme replacement in Tay-Sachs disease.

Enzyme replacement therapy was attempted with two Tay-Sachs-diseased individuals--a 14-month-old child and a 7-week-old infant. Treatment consisted of repeated weekly intrathecal injections of pure hexosaminidase A. Injection of this enzyme resulted in almost complete disappearance of GM2 from the serum, but did not bring about dissolution of the GM2 membranous cytoplasmic bodies in the brain, as detected by electronmicroscopy. Both patients tolerated the treatment without apparent clinical complications, but no clear-cut improvement was noted as a result of prolonged injections of hexosaminidase A. Since this treatment was initiated in both an advanced stage and a very early stage of the disease, we conclude that enzyme replacement treatment by this route is not beneficial for patients with Tay-Sachs disease.

Biopsy↗
PubMed1977

The metabolic effects of excess noradrenaline secretion from a pheochromocytoma.

We report a 14-year-old boy with severe hypertension who was cured by surgical removal of a pheochromocytoma. The tumor was shown biochemically and morphologically to secrete predominantly noradrenaline. The metabolic effects noted in this patient were raised free fatty acid levels and depressed insulin levels, hyperreninemia, hypercalcemia, and hypercalciuria with normal parathyroid function. All these abnormalities returned to normal after removal of the tumor. It is suggested that these effects were mediated via beta-adrenergic stimulation of the excess noradrenaline.

Adolescent↗
PubMed1977

Heterogeneity of Wilson's disease in Israel.

In a survey in Israel of 50 patients with Wilson's disease, it was found that this disease occurred in all ethnic groups. In the Arab patients there was a significantly early age of onset and the disease followed a more severe course than that in the Jewish patients. The overall sex ratio of patients was nearly 1:1, and genetic analysis of 20 families confirmed an autosomal recessive mode of inheritance. The very similar age of onset and type of disease within sibships and the varying ages of onset noted between the Arab and Jewish patients suggest that the disease is genetically heterogeneous.

Adolescent↗
PubMed1976

Fatal disseminated BCG infection. An investigation of the immunodeficiency.

A 2-year-old boy had a fatal disseminated BCG infection. Immunologic assessment showed a normal humoral response and normal numbers of E rosettes, normal thymus weight and histological features, but an abnormal response of lymphocytes in vitro and negative skin tests. Histological examination showed the presence of Gram-negative acid-fast bacilli within the macrophages. The possible mechanisms of immunodeficiency in this patient are discussed.

Animals↗
PubMed1976

Immunologic studies in phenylketonuria.

Significantly reduced immunoglobulins were found in 22 patients with phenylketonuria. Tests of cellular immune function which included delayed skin hypersensitivity, T rosettes and PHA transformation were normal. Escherichia coli antibodies and the booster response to tetanus toxoid were also normal.

Adolescent↗
PubMed1976

Abnormal renal functions in cyanotic congential heart disease.

Children with cyanotic congenital heart disease had a decreased glomerular filtration rate (71-8 +/- 18-9 ml/min per 1-73 m2) measured by endogenous creatinine clearances, compared with children who had had complete corrective surgery, children with noncyanotic heart disease, and normal children. There was a significant correlation between low glomerular filtration rate and haematocrit values above 50%. Daily urinary sodium excretion was reduced in the cyanotic patients.

Child↗