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Biomedical subjects

J Varga

Publications and source records attributed to J Varga.

At least 217 records · Page 12Linked to original sources
PubMed1990

Peripheral neuropathy associated with eosinophilia-myalgia syndrome.

In 1989, the Centers for Disease Control recognized the existence of an epidemic illness characterized by myalgia and eosinophilia in individuals taking preparations containing L-tryptophan. We evaluated 3 patients with eosinophilia-myalgia syndrome who presented with subacute progressive neuropathies. The neuropathies were predominantly motor and maximal in the lower extremities. Two patients were confined to a wheelchair and one was ventilator-dependent and bedridden. Sensory loss predominantly involved small fiber modalities. Electrophysiological studies showed multifocal marked conduction slowing and conduction block indicating segmental demyelination, with associated axonal degeneration that was accentuated distally. Examination of sural nerve biopsy specimens demonstrated axonal degeneration in all 3 patients and perivascular infiltrates in 2. Levels of quinolinic acid, a neurotoxic metabolite of L-tryptophan, were elevated in the cerebrospinal fluid in the 2 patients in whom it was measured. The cause of the neuropathy is unknown but may include immune mechanisms or toxicity of eosinophils, L-tryptophan, its metabolic products, or contaminants within L-tryptophan preparations.

Adult↗
PubMed1990

Evaluation of transforming growth factor beta and type I procollagen gene expression in fibrotic skin diseases by in situ hybridization.

Full thickness biopsies of affected skin and fascia from one patient with diffuse fasciitis and eosinophilia (DF), two patients with generalized morphea (GM), and five patients with progressive systemic sclerosis (PSS) of recent onset were examined for the expression of transforming growth factor beta 1 (TGF beta 1) and type I procollagen genes by in situ hybridization with human sequence-specific cDNA. An increased number of fibroblasts showing clearly detectable expression of pro alpha 1(I)collagen gene was found in all fibrotic lesions when compared with unaffected skin from the patient with DF and skin from two normal individuals examined in parallel. Expression of the TGF beta 1 gene was noted in a fibroblast subpopulation of the affected tissues from the patients with DF and GM. In contrast, the TGF beta 1 gene was not expressed at a detectable level in affected skin from the five patients with PSS. The results suggest that TGF beta 1 may play a role in the development of skin fibrosis in cases of DF and GM. However, from these studies, we cannot implicate TGF beta 1 in the pathogenesis of skin fibrosis in PSS.

DNA↗
PubMed1990

Interferon-gamma reverses the stimulation of collagen but not fibronectin gene expression by transforming growth factor-beta in normal human fibroblasts.

It has recently become apparent that several cytokines and growth factors are capable of modulating fibroblast proliferation and biosynthetic activity. To understand the role of these factors in connective tissue regulation, we examined the effects of the simultaneous addition of interferon-gamma (IFN-gamma) and transforming growth factor-beta (TGF-beta) on normal human dermal fibroblast collagen and fibronectin production. In addition, in vitro transcription rates and steady-state mRNA levels for these molecules were determined by nuclear run-off assays and Northern and dot-blot hybridization using specific human cDNA probes. Treatment of cultures with TGF-beta caused stimulation of collagen and fibronectin production. Addition of IFN-gamma to the TGF-beta-treated cultures abrogated the stimulatory effects of TGF-beta on collagen production in a dose-dependent manner and resulted in a net inhibition of collagen production. In contrast, the increase in fibronectin synthesis induced by TGF-beta was augmented further by IFN-gamma. These changes in collagen and fibronectin production were accompanied by parallel changes in the steady-state mRNA levels for these proteins. The effects of TGF-beta plus IFN-gamma on fibronectin gene expression appeared to be mediated entirely by transcriptional mechanisms, whereas the effects on collagen gene expression resulted from a combination of transcriptional and post-transcriptional events.

Cells, Cultured↗
PubMed1990

Serogroups of Campylobacter fetus and Campylobacter jejuni isolated in cases of ovine abortion.

Of 38 aborted ovine fetuses from 23 sheep flocks 29 C. fetus subsp. fetus and 22 C. jejuni were isolated and examined biochemically and serologically for heat-stable antigens. Serologic examinations were carried out by passive haemagglutination test. In case of C. fetus subsp. fetus strains alkaline antigen extraction was used. Antisera to two serogroups of C. fetus and to Penner serotype reference strains 1 to 60 were produced in rabbits. Abortion was caused in 18 (78.3%) flocks by C. fetus subsp. fetus and in 5 (21.7%) flocks by C. jejuni. Six C. fetus subsp. fetus strains grew well at both 43 and 25 degrees C. With one exception all C. fetus subsp. fetus were resistant, whereas all 29 C. fetus subsp. venerealis strains were sensitive to 30 micrograms/ml cefoxitin and cefamandole. These two cephalosporins can be used to differentiate the two subspecies of C. fetus. Passive haemagglutination test using alkaline antigen extraction is a proper method for the examination of heat-stable antigens of both C. fetus subspecies. Out of 24 C. fetus subsp. fetus strains 13 belonged to serogroup A(01), and 11 to serogroup B(02). C. jejuni strains examined belonged to Penner serogroup 1 (6 strains), to serogroup 5 (4 strains) and to serogroup 8 (4 strains).

Abortion, Veterinary↗
PubMed1990

Serogroups of Campylobacter jejuni from man and animals.

A total of 186 campylobacter strains from aborted calf and sheep fetuses, from scouring dogs, rabbits and man, and from retailed poultry were isolated and examined biochemically and serologically for heat stable antigens. Immune sera were produced in rabbits against Penner reference strains from 1 to 60, and against two field isolates. Out of 186 biochemically tested strains 179 (96.2%) proved C. jejuni and only 6 (3.2%) C. coli. One strain has been identified as C. laridis. In cattle and sheep 3.2 and 21.7% respectively of all campylobacter abortions were due to C. jejuni infection. The same agent caused 12.7% of diarrhoea of dogs. The campylobacter infection rate of freshly slaughtered and dressed chicken varied between 25 and 64.3%. Out of the serologically examined 140 C. jejuni strains 118 (84.3%) could be assigned to 16 Penner serogroups and 13 (9.3%) to 2 further serogroups. Serogroups 8 (31.4%), 1 (19.3%) and 2 (12.1%) occurred most frequently. The human isolates represented the widest serotype distribution, as 32 tested strains belonged to 12 serogroups. All those serogroups which caused abortion or diarrhoea in animals or were isolated from poultry carcases were isolated also from man with diarrhoea, but some serogroups were found only in man.

Animals↗
PubMed1990

Characterization of Actinobacillus strains isolated from aborted swine fetuses.

Eleven Actinobacillus strains were isolated in pure culture from 12- to 13-week-old aborted swine fetuses. Apart from minor biochemical differences, they resembled strains isolated from sow vaginas by Ross et al. (1972) in the U. S. A. Some of the strains agglutinated sheep, cattle and horse but not pig, dog and chicken erythrocytes. Haemagglutination was mannose resistant and could be inhibited by specific hyperimmune serum. Heating above 70 degrees C diminished or abolished haemagglutination of the cultures. Electron microscopy showed no fimbriae on the surface of the bacteria.

Abortion, Veterinary↗
PubMed1990

[Occurrence and significance of different Campylobacter types in domestic animals in Hungary].

Experiences, including results of original experimental work on Campylobacter fetus, C. jejuni and C. coli induced diseases of cattle, sheep, dogs, rabbits poultry and men in Hungary are reviewed. Out of 31 cases of abortion in cows 29 (93.5%) were causes by C. fetus subsp. venerealis and only one case each (3.2%) by C. fetus subsp. fetus and C. jejuni, respectively. Out of the 29 strains of C. fetus subsp. venerealis, 26 belonged to serogroup 01 (A) and only 3 to serogroup 02 (B). Campylobacter abortions in sheep flocks were caused in 18 cases (78.3%) by C. fetus subsp. fetus and in 5 cases (21.7%) by C. jejuni. The latter strains belonged to Penner's serogroup 1 (6 strains), 5 (4 strains) and 8 (5 strains), respectively. In scouring dogs 12.7% of the cases were caused by C. jejuni. The same pathogen caused diarrhoea also in young rabbits. Isolated strains belonged to serogroup 2. In cases of Campylobacter hepatitis of laying hens, egg production has been reduced by 8 to 15% for 2 to 3 weeks. Row poultry meat represents often the source of infection for men. The 32 strains of C. jejuni isolated from faecal samples of men affected with diarrhoea belonged to 12 serogroups.

Abortion, Veterinary↗
PubMed1990

Hypoglycemia due to antiinsulin receptor antibodies in systemic lupus erythematosus.

An elderly woman with unexplained episodic fasting hypoglycemia was hospitalized for ascites. Evaluation revealed polyserositis, arthritis and immunologic abnormalities that suggested the diagnosis of systemic lupus erythematosus (SLE). Antibodies to insulin receptor with insulin binding inhibitory activity were detected in her serum. Treatment with prednisone was accompanied by resolution of hypoglycemic episodes and disappearance of the antireceptor antibodies. Autoantibody mediated alterations in serum glucose may be included in the growing list of autoimmune phenomena in SLE. Antiinsulin receptor antibodies should be sought in patients with SLE and idiopathic hypoglycemia.

Aged↗
PubMed1989

Systemic sclerosis after augmentation mammoplasty with silicone implants.

We describe four women who presented with systemic sclerosis several years after cosmetic augmentation mammoplasty with silicone-gel implants. The interval between implantation mammoplasty and the onset of systemic sclerosis ranged from 6 to 15 years. All patients fulfilled the criteria established by the American Rheumatism Association for systemic sclerosis and had Raynaud phenomenon, arthralgia, and evidence of pulmonary or gastrointestinal involvement. Enlargement of lymph nodes draining the prostheses was noted in two patients. Antinuclear antibodies were detected in three patients and showed speckled or nucleolar patterns. Removal of the prostheses in two cases did not result in improvement of systemic sclerosis. Evidence of silicone leakage from the implants included the following. The observation by light microscopy of refractile particles in tissues distant from the prostheses, the observation by electron microscopy of electron-dense structures consistent with silica, and the definitive identification of the element silicon by energy-dispersive analysis in these electron-dense structures. A marked, chronic inflammatory infiltrate containing lymphocytes, "foamy" histiocytes, and larger numbers of multi-nucleated giant cells with vacuoles and asteroid bodies was found at the same sites. Our demonstration that silicone escapes from elastomer-silicone-gel breast implants and appears to be closely associated with a chronic inflammatory reaction suggests that silicone plays a role in the development of certain cases of systemic sclerosis.

Adult↗
PubMed1989

Transforming growth factor-beta stimulation of lung fibroblast prostaglandin E2 production.

Transforming growth factor-beta (TGF beta) stimulated the production of total protein, collagen, and fibronectin by normal human lung fibroblasts. The stimulatory response was maximal at 100 pM TGF beta and reversed toward control at higher concentrations. Inhibition of fibroblast prostaglandin (PG) synthesis enhanced TGF beta-induced stimulation of total protein, collagen, and fibronectin production and reversed the negative slope of the dose-response curve at high concentrations of TGF beta. Determination of the steady-state levels of Types I and III procollagens and fibronectin mRNAs employing specific cDNA probes demonstrated that inhibition of fibroblast PG production increased the stimulatory effect of TGF beta on the levels of these transcripts. Exogenous PGE2 abrogated the stimulatory effects of TGF beta. These findings suggest that fibroblast stimulation by TGF beta may be down-regulated by endogenous PG synthesized in response to TGF beta. This notion was supported by the demonstration that TGF beta markedly stimulated fibroblast PGE2 production. These results indicate that TGF beta-induced stimulation of fibroblast PGE2 production may be an autoregulatory control mechanism to limit the effects of TGF beta on connective tissue protein synthesis.

Blotting, Northern↗
PubMed1989

Biochemical and serological properties of Actinobacillus pleuropneumoniae biotype 2 strains isolated from swine.

The biochemical and serological properties of 21 strains of Actinobacillus pleuropneumoniae biotype 2 isolated from haemorrhagic necrotic pleuropneumonia of swine were examined. For serologic typing, the indirect haemagglutination (IHA) and the double gel-diffusion tests were used. On the basis of their soluble surface antigens, our A. pleuropneumoniae biotype 2 isolates could be assigned to two proposed serotypes. Serotype 1 comprised 11 strains and serotype 2 comprised 10 strains. All strains contained two surface antigen components. In the strains belonging to serotype 1, one of the antigens was identical with the serotype-specific antigen of Pasteurella haemolytica T4. Both antigens of serotype 2 strains proved to be type-specific. Four strains received from Switzerland, including the holotype strain of A. pleuropneumoniae biotype 2, and three strains isolated from swine in the G.D.R. belonged to serotype 2. Both the double gel diffusion and the IHA tests detected a 2-way cross-reaction between biotype 1, serotype 2 and biotype 2, serotype 2 strains of A. pleuropneumoniae, which could be eliminated using cross-absorbed sera.

Actinobacillosis↗
PubMed1989

In-vitro activity of cefetamet (Ro 15-8074) compared with other oral agents.

The bacteriostatic and bactericidal activities of cefetamet (Ro 15-8074) were compared with those of cefadroxil, cefaclor, ampicillin, doxycycline, chloramphenicol and erythromycin against a total of 400 bacterial strains isolated from nosocomial respiratory tract and auditory canal infections. The broth macrodilution method was used to determine antimicrobial susceptibility. None of the compounds was effective against Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus strains. Cefetamet was very active against ampicillin-resistant Klebsiella pneumoniae. Proteus mirabilis and Escherichia coli strains with the minimal inhibitory concentrations for 90% of the strains tested ranging from 0.25 to 1 mg/l. Cefetamet at a concentration of 8 mg/l inhibited 90% of Enterobacter aerogenes and 60% of S. epidermidis strains. In biophotometric studies, subinhibitory concentrations of cefetamet greatly lengthened the lag-phase and flattened the log-phase, the extent varying with the concentrations and species tested. It did not cause detectable lysis in the stationary-phase of the cultures. Adding two to 32 times inhibitory concentrations of cefetamet to middle-log cultures, no or moderate lysis occurred., except with Esch. coli. This observation suggests that cefetamet is primarily bacteriostatic for some of the strains tested.

Anti-Bacterial Agents↗