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Biomedical subjects

S Yatziv

Publications and source records attributed to S Yatziv.

At least 37 records · Page 2Linked to original sources
PubMed1986

Termination of absence status and suppression of inter-ictal bursts with phenytoin: case report.

An 11 year old female with a first episode of absence status is described. Clinical manifestations, ictal and post-ictal EEGs were generalized. An IV loading dose of phenytoin resulted in an abrupt cessation of both clinical and EEG ictal phenomena, and later was found to be effective in suppressing inter-ictal bursts of 3 per second spike and slow wave discharges. This response is unusual since phenytoin is considered ineffective in controlling petit mal epilepsy.

Child↗
PubMed1986

Clinical and laboratory study in 22 patients with inherited hyperammonemic syndromes.

Twenty-two patients with inherited hyperammonemic syndromes are presented. These patients represent 22 different families. The diagnosis was based mainly on family history, blood ammonium levels, acid base balance, urinary orotic acid, urinary and plasma amino acids and organic acids. The final diagnosis was confirmed by determination of liver enzyme activity. In 12 patients (54%), the first clinical manifestations were noticed after the neonatal period; 7 patients (31%) were diagnosed after infancy, and 8 (23%) after the age of 8 years. Two patients who represent the late-onset group of inherited hyperammonemic syndromes are presented in detail. The three most common diagnoses were ornithine transcarbamoylase deficiency, carbamoyl phosphate synthetase deficiency, and lysinuric protein intolerance, which comprised 59% of the diagnosed patients. Our data, based on one of the largest series reported, reveal a relatively large percentage of late-onset inherited hyperammonemic syndromes as compared with previous reports.

Amino Acid Metabolism, Inborn Errors↗
PubMed1985

Human ciliated epithelial cells from nasal polyps as an experimental model for Mycoplasma pneumoniae infection.

Human ciliated epithelial cells derived from nasal polyps and cultured in a monolayer were studied as an experimental model for Mycoplasma pneumoniae infection. Scanning electron microscopy revealed two types of cultured epithelial cells: one which was covered by microvilli only and another which had microvilli and actively beating cilia. M. pneumoniae adhered to both types of cells, and the adherence followed saturation kinetics as a function of time. Infection of the cells for 20 h resulted in 75% inhibition of their intracellular catalase activity and a 3.5-fold increase in their malonyldialdehyde levels compared with noninfected controls. This indicates the presence of cellular oxidative damage due to M. pneumoniae infection. It is suggested that human nasal ciliated epithelial cells may serve as a representative model for studying M. pneumoniae in relation to its natural host.

Adhesiveness↗
PubMed1984

Role of superoxide anion in host cell injury induced by mycoplasma pneumoniae infection. A study in normal and trisomy 21 cells.

The role of Mycoplasma pneumoniae-generated superoxide and hydrogen peroxide in inducing host cell injury was studied in normal and trisomy 21 human cells. As a result of M. pneumoniae infection, catalase activity in infected normal skin fibroblasts and ciliated epithelial cells decreased by 74-77% as compared with uninfected controls. Addition of superoxide dismutase to the infected cultured cells totally prevented the inhibition whereas addition of catalase or catalytically inactivated superoxide dismutase had no protective effect. Trisomy 21 erythrocytes and cultured skin fibroblasts in which CuZn-superoxide dismutase content is 50% greater than in normal cells were infected by M. pneumoniae. The inhibition of catalase activity in these cells was 7-33% and 0-20.5%, respectively, as compared with 65-72% and 48-68% inhibition in normal infected controls. Following M. pneumoniae infection, the levels of malonyldialdehyde, an indicator for membrane lipid peroxidation were raised in trisomy 21 cultured fibroblasts by 10-32% while in normal cells malonyldialdehyde increased by 140-870%. Externally added superoxide dismutase, but not catalase, reduced the extent of lipid peroxidation in normal infected cells. Lactate dehydrogenase release from normal infected cells was time correlated with the increase in their malonyldialdehyde formation. It is suggested that superoxide generated during M. pneumoniae infection is involved in the inhibition of host cell catalase activity. The inactivation of this cellular antioxidative defense mechanism results in progressive oxidative damage to the M. pneumoniae-infected cells.

Catalase↗
PubMed1983

Distribution of actin, myosin and actin binding protein in platelets of patients with hyperlipoproteinemia.

Significant anomalies in the quantity and relative distribution of the contractile proteins actin, myosin and actin binding protein (ABP) were observed in platelets obtained from patients with hyperbetalipoproteinemia (type IIa) and in patients with hypertriglyceridemia (type IV). Changes were observed in unfractionated platelets, (increased ABP in type IIa patients and increased actin in both type IIa and type IV) in isolated platelet membranes (increased ABP and actin in type IV, and increased myosin in type IIa) and in the KCl extract of platelets (increased actin in type IV and increased myosin in type IIa). The myosin ATPase specific activity was increased in platelets of type IV patients. No changes were observed in the concentrations and distribution of membrane glycoproteins in the platelets of these patients. The above anomalies in the contractile proteins might be relevant to the known functional anomalies of the platelets of patients with hyperlipoproteinemias.

Actins↗
PubMed1983

Clinical heterogeneity in a sibship with Niemann-Pick disease type C.

The clinical presentation of Niemann-Pick type C is variable. However, in families hitherto described, the affected individuals in a given sibship show a similar clinical course. A family with histological and biochemical findings of Niemann-Pick type C is described. Four of the affected siblings presented with an early onset and a fulminant course resembling Niemann-Pick type A, whereas in the fifth sibling a later onset and a much slower neurological deterioration was observed. Genetic counseling in families with Niemann-Pick type C should take into consideration the possibility of clinical heterogeneity within the same sibship.

Fibroblasts↗
PubMed1983

Inhibition of host cell catalase by Mycoplasma pneumoniae: a possible mechanism for cell injury.

This study demonstrates that viable Mycoplasma pneumoniae cells inhibit catalase activity in several types of intact human cells as well as in solution. Human erythrocyte catalase was inhibited up to 72%, and the inhibition of catalase in human cultured skin fibroblasts, lung carcinoma epithelial cells, and ciliated epithelial cells from human nasal polyps ranged between 75 and 80%. UV light-killed mycoplasmas failed to inhibit catalase activity both in intact cells and in vitro. After M. pneumoniae infection of human cultured skin fibroblasts, the level of malonyldialdehyde, an indicator for membrane lipid peroxidation, was 3.5 times higher than in control fibroblasts. Virulent M. pneumoniae completely inhibited catalase activity in solution, whereas the nonvirulent strains had a lesser ability to inhibit catalase activity. These findings suggest that as a result of host cell catalase inhibition by M. pneumoniae, the toxicity of the hydrogen peroxide generated by the microorganism and the affected cell is enhanced, thereby inducing host cell damage.

Catalase↗
PubMed1982

Coexistence of Gaucher Disease and Philadelphia positive chronic granulocytic leukemia.

A patient with coexistent Gaucher disease and Philadelphia positive chronic granulocytic leukemia (CGL), who subsequently developed myeloblastic leukemia, is described. The diagnosis of CGL was established according to standard clinical, morphological, biochemical, and cytogenetic data, while the diagnosis of true Gaucher disease was based on biochemical data and the presence of Gaucher cells with typical ultrastructural features in the bone marrow and spleen. Enzyme studies showed low activity of ceramide-beta-glucosidase in the patient's peripheral blood leukocytes, skin fibroblasts, and splenic tissue and the presence of increased amounts of ceramide-beta-glucoside in the spleen. This case is reported in order to draw attention to the possible coexistence of these two diseases in the same patient, as opposed to the well-recognized finding of "Gaucher-like" cells in the bone marrow of patients with CGL. Enzyme studies enable distinction between these two situations.

Chromosomes, Human, 21-22 and Y↗
PubMed1982

Long-term enzyme replacement therapy in beta-glucuronidase--deficient mice by allogeneic bone marrow transplantation.

Enzyme replacement therapy was successfully accomplished in beta-Glu-deficient C3H/HeJ mice after transplantation of BM cells obtained from normal BALB/c donors. Marrow recipients were prepared for transplantation by fractionated TLI. Enzyme activity increased from 20.5 +/- 7.0 nmol/mg of protein per hour to 180 +/- 30.2 in the liver (p less than 0.001) and from 8.2 +/- 2.0 to 17.5 +/- 5.0 nmol/ml/hr in the plasma (p less than 0.05) at 50 days after marrow infusion. Normal enzyme activity was maintained in treated mice for at least 100 days after marrow transplantation, as documented by repeated liver biopsies and examination of plasma samples. The marrow donors and the recipients were fully histoincompatible. Both immunologic rejection of the marrow allograft and GVHD were prevented by the prior conditioning of the recipients with TLI, resulting in bilateral transplantation tolerance of host vs. graft and graft vs. host. The data suggest that allogeneic BM transplantation may provide a possible therapeutic approach for certain enzyme deficiency syndromes.

Animals↗
PubMed1981

An unusual form of metachromatic leukodystrophy in three siblings.

An unusual form of Metachromatic Leukodystrophy (MLD) has been described in three siblings who are the sole children of related parents of Iranian origin. Clinical progression in the three siblings was insidious and protracted, the hallmark of the condition being a dystonia mainly induced by intention and manifested by dysarthria and torsion spasm of the neck, spine and extremities. The dysarthria sometimes culminated in apparent choreoathetosis. Laboratory studies included positive sural nerve biopsies, prolonged nerve conduction times and a marked deficiency of arylsulfatase A in the urine, leukocytes and fibroblasts. The parents presented no clinical manifestations, but the arylsulfatase A activity in both was reduced by 50%.

Adolescent↗
PubMed1981

Familial pellagra-like skin rash with neurological manifestations.

A 14-year-old boy of Arabic origin presented with a pellagra-like rash and neurological manifestations including ataxia, dysarthria, nystagmus, and coma. There was a striking response to oral nicotinamide. The laboratory findings were not typical of Hartnup disease: aminoaciduris and indicanuria were absent and there was no evidence of tryptophan malabsorption. Tryptophan loading did not induce tryptophanuria nor did it increase excretion of xanthurenic or kynurenic acids. These findings support the possibility of a block in tryptophan degradation. The family history suggests a genetically-determined disorder.

Adolescent↗
PubMed1981

Myopathy in hyperornithinemic gyrate atrophy of choroid and retina.

Five patients in two families with hyperornithinemia and gyrate atrophy (HOGA) of the choroid and retina are reported. All patients had marked muscle wasting. Biochemical studies revealed high levels of plasma ornithine and low levels of plasma lysine. Muscle biopsies were performed in four patients and showed subsarcolemmal accumulation of pleomorphic mitochondria and tubular aggregates. These findings suggest that muscle wasting in HOGA is associated with a myopathy that is probably secondary to hyperornithinemia and/or hypolysinemia.

Adolescent↗
PubMed1980

Correction of enzyme deficiency in mice by allogeneic bone marrow transplantation with total lymphoid irradiation.

Enzyme deficiency was corrected in mice after allogeneic bone marrow transplantation with occurrence of graft versus host disease. beta-Glucuronidase-deficient C3H/HeJ mice were treated with total lymphoid irradiation. Normal bone marrow cells (30 X 10(6)) from BALB/c to C3H/HeJ chimeras (>90 percent circulating donor-type cells) without graft versus host disease. beta-Glucuronidase activity increases to normal levels in all chimeras as measured in the liver and in the plasma. Activity was maintained throughout an observation period of 7 months.

Animals↗