Biomedical subjects

E Nagy

Publications and source records attributed to E Nagy.

At least 127 records · Page 7Linked to original sources

PubMed1998

Neuroimmunoregulation and cancer (review).

It is certain that neuroimmune mechanisms play a role in host defence against cancer. However, this interaction is highly complex and many variations are possible according to the nature of the neoplasms involved. There are indications that adaptive immunity is present in a significant proportion of tumor bearing hosts, and this defence may be boosted by specially designed vaccines and cytokines. Natural immune mediators are also implicated in resistance against tumor development. Here we review the evidence suggesting that hormonal manipulation of the host can result in the elevation of immune defences against cancer. Such manipulation strengthens both the adaptive and natural immune defences of the host, both of which play significant roles. Natural defence mechanisms are boosted by cytokines and hormones during febrile reactions which are now known as the acute phase response. It is suggested that hormonal stimulation of immune mechanisms coupled with the usual immunostimulants already in use may be employed to good advantage for the combination immunotherapy of cancer. Modern molecular biology approaches permit the development of laboratory monitoring procedures which may be used for the prediction and follow-up of therapeutic success.

Acute-Phase Reaction↗

PubMed1998

Analysis of infectious laryngotracheitis virus isolates from Ontario and New Brunswick by the polymerase chain reaction.

The polymerase chain reaction (PCR) was used to amplify DNA of infectious laryngotracheitis virus (ILTV) isolates obtained from field specimens. The examined 47 samples included 37 isolates representing 35 cases of infectious laryngotracheitis from Ontario and 10 isolates originating from 10 field cases in New Brunswick. The viruses were grown in either embryonated chicken eggs or cell culture, the DNA extracted and amplified using primers designed from the sequence information of a 1.1 kb BamHI fragment of the Ontario 1598 ILTV strain. Thirty-four of the Ontario isolates and all of the New Brunswick isolates were amplified successfully. This suggests that the selected primers would be useful for the majority of the isolates encountered in outbreaks of ILTV.

Animals↗

PubMed1998

The possible role of anaerobic bacteria in chronic prostatitis.

Prostatis, the most common urological disease in men, afflicts between 25 and 50% of all adult men. Four clinical categories are recognized: acute and chronic bacterial prostatitis, non-bacterial prostatitis and prostatodynia. The role of Gram-positive aerobic bacteria and the different anaerobes in chronic bacterial prostatitis is still a matter of debate. During this study, the urethral discharge and the prostatic fluid obtained after prostatic massage of 50 patients with chronic prostatitis, confirmed by clinical examination and resistant to empirical quinolone therapy, were cultured under aerobic and anaerobic conditions. The parallel specimens from 24 patients exhibited high colony counts of Gram-positive and Gram-negative anaerobic bacteria, either alone (18 cases) or in combination with aerobic bacteria (6 cases). The specimens obtained after prostatic massage of the remaining 26 patients were completely negative for both aerobic and anaerobic bacteria. No Chlamydia trachomatis, Mycoplasma hominis, Ureaplasma urealyticum or Trichomonas vaginalis were isolated from these patients. Patients with chronic prostatitis who gave positive culture results for anaerobes were treated with amoxicillin/clavulanic acid or clindamycin for 3-6 weeks. After treatment, samples were again taken and cultured for all pathogens known to cause prostatitis. These post-therapeutic samples revealed a decrease or total elimination of the symptoms, and no anaerobic bacteria could be detected.

Adult↗

PubMed1998

[Vitamin K: biochemistry, function, and deficiency. Review].

Vitamin K is a cofactor for the synthesis of blood coagulation Factors II, VII, IX and X, and inhibitors such as Protein C and S and bone matrix protein. Its active form is a coenzyme in the glutamic acid carboxylation. Vitamin K-dependent factors form enzymatic complexes with calcium and membrane phospholipids. The insufficiency of gamma glutamic carboxylation impairs the hemostatic function. Hereditary deficiencies, antibiotics and oral anticoagulants, decrease the capacity of complex formation giving way to hemorrhage or thrombosis, or bone mass disturbances which are easily treated with administration of Vitamin K. The main causes of Vitamin K deficiency are lack of hepatic storage in newborns, liver insufficiency, malabsorption, dietetic deficiency, therapy with the antibiotics and coumarin administration. For the study of Vitamin K there are methods to measure the Vit K dependent proteins and as well methods to measure specifically the quinonas.

Adult↗

PubMed1998

The association of titers to bovine coronavirus with treatment for bovine respiratory disease and weight gain in feedlot calves.

The association between bovine respiratory disease (BRD) and antibody titers to bovine coronavirus (BCV) was studied in 604 calves (19 different groups in 4 different feedlots from 2 provinces). Almost all calves had antibody titers on arrival in the Alberta feedlot and 82% of the calves had an antibody titer on arrival at the Ontario feedlots; titers in calves in Alberta were almost twice as high as those in calves in Ontario. The incidence of infection, in the first mo after arrival as judged by seroconversion, ranged from 61% to 100%; titer increases were much greater in calves in Ontario feedlots. Titer variables were not significantly related to BRD, except on a within-group basis (group was a confounding variable for BCV-BRD associations). Given control of group effects, calves with an antibody titer on arrival appeared to be protected against BRD for the first 28 d in the feedlot, and the association was reasonably linear over the range of titers. Each titer unit on arrival decreased the risk of BRD by about 0.8x (odds ratio). Titer change was not strongly related to the risk of BRD and the relationship was not linear over the range of titer changes. Titer change was strongly and negatively correlated with titer on arrival, and titer change was not significantly related to BRD in the presence of arrival titers. Arrival titer retained its relationship with BRD in the presence of titer data for other putative pathogens. Each higher unit of titer to BCV on arrival increased the 28-day weight gain (controlling for group, initial weight and the occurrence of BRD) by slightly more than 1 kg. Titer change was associated with decreased weight gain, when initial titer was not in the model. The lack of a linear or multivariable association between BCV titer change and BRD, and weight gain, may indicate that BCV is not a major pathogen; or, its lack of significance may merely be due to its strong correlation with arrival titer. Given the associations found in this study, particularly the interprovincial differences in arrival titers, more and different approaches to studying the possible effects of BCV on BRD are in order.

Animals↗

PubMed1998

The association of titers to Haemophilus somnus, and other putative pathogens, with the occurrence of bovine respiratory disease and weight gain in feedlot calves.

Serum samples were obtained from 602 calves (from 19 groups in four feedlots: three in Ontario, and one in Alberta) upon arrival at the feedlot and 28 d later. Of these calves, 202 developed bovine respiratory disease (BRD) and 400 did not develop BRD. Based on high antibody titers noted upon arrival, we infer that most calves were exposed to Haemophilus somnus prior to arrival at the feedlot. Within a group, calves with high titers on arrival had a reduced risk of developing BRD later. Most calves did not experience titer increases after arrival; however, calves that had stable or increasing titers had a relatively low risk of contracting BRD. The calves at greatest risk of BRD were those with titers on arrival of less than 6.8 units and subsequent titer decreases of more than 1 unit. The effects of both the titer on arrival and the titer change after arrival were stable when the serologic effects of a number of viruses and Mycoplasma agents were considered. Neither antibody titer on arrival nor titer change was related to weight gain differences among calves. Calves with BRD or calves with lower weight on arrival had decreased weight gains in the first 28-day feeding period. The high titers on arrival may have protected most calves against further infection with H. somnus. However, since the calves that developed BRD had large titer increases to a number of viruses and to Pasteurella haemolytica, while having decreased antibody titers to H. somnus, we infer that the existing antibodies were "used up" in combatting the agents, including H. somnus, which may have "caused" the BRD. Calves which were able to increase their antibody levels to H. somnus tended to have a reduced risk of BRD.

Animals↗

PubMed1998

On the role of Na,K-ATPase: a challenge for the membrane-pump and association-induction hypotheses.

The regulation of cellular ion levels has been an important issue of cell physiology since the beginning of the century. A special interest was focused on the monovalent ions which are involved in several cellular functions; in fact, the maintenance of high K+ level inside the cells is one of the most basic life-phenomena. Regarding the regulation of monovalent ions in general, two opposing ideas emerged: one being the membrane theory and the other the sorption theory(ies). Today most scientists are familiar only with the membrane theory which involves the pump and leak hypothesis and only a few consider the predictions of the association-induction hypothesis which may be classified as one of the sorption theories. In the regulation of monovalent ions the Na,K-ATPase is a key-molecule according to the membrane theory but not considered that important by the association-induction hypothesis. In this paper, we present two simple experiments which demonstrate the possible role of this molecule in the regulation of cellular Na+, K+ homeostasis and also disprove the pump and leak hypothesis.

Animals↗

PubMed1998

The microflora associated with human oral carcinomas.

Both local and systemic infections may complicate the morbidity of patients with oral malignant neoplasms, particularly those presenting intraorally. This study investigated the microbial contents of the biofilms present on the surfaces of oral squamous cell carcinomas. Biofilm samples were obtained from the central surface of the lesions in 21 patients (20 male, 1 female) aged 52.8 (+/- 8.2) years, and from contiguous healthy mucosa, before any antibiotic therapy or any tumour treatment. All lesions were keratinising squamous cell carcinomas with surface ulceration. Samples were transported in reduced brain heart infusion (BHI) broth and cultured within 1 h of removal, using aerobic and anaerobic complete and selective media. The median number of anaerobic colony forming units (CFU/ml) at the tumour sites (1.6 x 10(8)) was significantly higher than for the healthy (control) mucosa (3.0 x 10(7); P = 0.0001, Wilcoxon); the same was true for aerobes at the tumour sites (1.51 x 10(8)) relative to the controls (2.8 x 10(7); P = 0.0008, Wilcoxon). The species isolated in increased numbers at tumour sites were Veillonella, Fusobacterium, Prevotella, Porphyromonas, Actinomyces and Clostridium (anaerobes), and Haemophilus, Enterobacteriaceae and Streptococcus spp. (aerobes). Candida albicans was found at eight of the 21 tumour sites, but never at control sites. It was concluded that human oral carcinoma surface biofilms harbour significantly increased numbers of aerobes and anaerobes as compared with the healthy mucosal surface of the same patient. Candida albicans can also be present in these biofilms. These findings must be considered in relation to the known predisposition of such patients to systemic infections, and to the unpleasant complications of oral morbidity due to infected lesions.

Adult↗

PubMed1998

Investigation of the presence of different broad-spectrum beta-lactamases among clinical isolates of Enterobacteriacae.

Chromosomal or plasmid-encoded beta-lactamases are the most frequent causes of resistance to broad-spectrum beta-lactam antibiotics in clinical isolates of Gram-negative bacteria. Different screening methods can be used for their detection during routine laboratory work, while molecular biological methods may help in the detection of the genetic background of the phenotypic resistance. Clinical isolates of Klebsiella pneumoniae (170) and Enterobacter cloaceae (82) were obtained from different parts of Hungary, whereas those of Serratia marcescens (15) were isolated in our Department from a nosocomial outbreak. Disk diffusion and the Etest were used to screen inducible Class C beta-lactamase and plasmid-mediated extended spectrum beta-lactamases (ESBLs) among clinical isolates of Enterobacteriaceae. Single-strand conformation polymorphism (SSCP) analysis of the PCR products obtained after using SHV-specific primers revealed the presence of SHV-2 and SHV-5 ESBL among 170 K. pneumoniae strains in 12 and 3 cases, respectively. The results of the screening methods and the PCR-SSCP analysis suggested that 14 of the 15 S. marcescens strains not only produced the Class C, inducible chromosomal beta-lactamase, but also acquired a plasmid-mediated SHV-2-type ESBL. One strain isolated from the environment during the outbreak was genetically related to the other isolates, as demonstrated by the different typing methods, but it did not produce ESBL. The in vivo transfer of SHV-2 gene was assumed from an SHV-2 positive K. pneumoniae strain present in the same ward, in the same patient and at the same time. A very high prevalence of the stable derepressed mutants of E. cloaceae was confirmed among the Hungarian isolates. Seventy seven per cent of the strains produced high amounts of beta-lactamase without induction being responsible for their resistance to third-generation cephalosporins. Nineteen per cent of the strains were inducible when cefoxitin or imipenem was used, as confirmed by direct measurement of the MICs with the Etest.

Anti-Bacterial Agents↗

PubMed1997

[Serodiagnosis of toxoplasmosis].

Generally, toxoplasmosis has mild symptoms, or is asymptomatic, in patients with intact immune system. The infection, however, may have serious consequences in immunodeficient or immunosuppressed patients, as well as in the off-springs of pregnant women. If the mother has acute toxoplasmosis during the pregnancy, the passage of parasites through the placenta may result in the death of the fetus, or, in the severe damage of the fetus or neonate. All these consequences can be prevented by the early detection of the disease followed by the immediate therapy of the mother. Contrary to the most infectious diseases, however, the high specific IgM level has not proved to be a reliable marker of the acute infection in the case of toxoplasmosis. Therefore, in the case of infections discovered in the "plateau" period [i.e. with persistent IgM ("residual" IgM) and/or persistent high level of IgG antibody), the "acute" and the "chronic" phases can be distinguished more reliably by the detection with ELISA of the IgA antibody response to the so called P30 protein of Toxoplasma gondii. The anti-P30 IgA antibody response appears very early and generally disappears in 3-9 months. Thus, it is possible to discriminate the acute phase of the disease from the harmless chronic phase. Between 1987 and 1996, practically all pregnant women in Szeged and its region (altogether 21,952 women), underwent serologic toxoplasma screening. Among them, 124 pregnant women were found highly suspicious for having acute toxoplasmosis. Appropriate counselling, followed by spiramycin therapy during pregnancy and regular ultrasound examination were their antenatal management. No clinically manifested fetal or neonatal infection was observed. The screening and treatment schedule seems to be promising in the prevention of fetal and neonatal toxoplasmosis.

Adult↗

PubMed1997

[Lipoprotein (a) studies in thyroid diseases].

High lipoprotein (a) levels have been established as a risk factor for atherosclerosis. The physiological and pathological function of lipoprotein (a) and the effect of other factors of lipoprotein (a) plasma concentrations are not well known. The role of thyroid hormones concerning Lp(a) plasma concentrations are not fully cleared. The Lp(a) levels are genetically determined, relatively stable, while the thyroid hormones react differently. 30 hyperthyroid and 29 hypothyroid patients were studied. The thyroid status and lipid parameters were investigated. A significant correlation was observed between the cholesterol, triglyceride, LDL-cholesterol, Apolipoprotein B and the thyroid hormone levels. The HDL-cholesterol and Apolipoprotein A correlated inversely with the thyroid hormone levels. Data obtained on the Lp(a) and thyroid hormone was in contrast with those of other studies. Hyperthyroid patients were increased Lp(a) concentrations as compared those of euthyroid subjects. In severe thyreotoxicosis (especially with high levels of antithyroid antibodies) elevated Lp(a) plasma concentrations were found. In hypothyroid patients the high levels of Lp(a) were measured as described in previous studies. Authors concluded that further studies are needed to investigate this phenomenon.

Apolipoproteins A↗

PubMed1997

[Aorto-bi-subclavian bypass in the treatment of left subclavian steal syndrome and stenosis of the innominate artery].

Authors report a case of a left side subclavian steal syndrome, caused by occlusion of the subclavian artery, combined with a high grade stenosis of the innominate artery. The rare combination of arteriosclerotic lesions of the supraaortic arteries have been treated by an aorto-bisubclavian bypass procedure performed from a median sternotomy. This is the first publication of this method in the Hungarian surgical literature.

Angiography↗

PubMed1997

[Low dose ACTH therapy in West syndrome].

Ten patients with infantile spasms were treated with low dose ACTH therapy during the last five years. The etiology, EEG, the clinical features and the efficacy of the treatment were found to be similar to the data published in the literature. The early diagnosis, etiological classification and the appropriate therapy of the disease were important to obtain a better outcome. The low dose (20-40 UE) ACTH therapy proved to be effective.

Adrenocorticotropic Hormone↗

PubMed1997

Interaction of AU-rich sequence binding proteins with actin: possible involvement of the actin cytoskeleton in lymphokine mRNA turnover.

In the current study, we report that cytochalasin-induced disruption of microfilaments stabilizes lymphokine mRNAs in activated human peripheral blood lymphocytes. Parallel with this, a dose- and time-dependent increase in AU-rich sequence binding protein (AUPB) activities is apparent in the nonionic detergent-resistant fractions of these cells, suggesting that cytochalasin-induced modulation of lymphokine mRNA stability might be mediated through cytoplasmic AUBPs. We provide evidence that some of the AUBPs can be immunoprecipitated with anti-actin antibodies, implicating the potential of these proteins to associate with the actin-based cytoskeleton in vivo. Moreover, disruption of the microfilament network by cytochalasins produces increased immunoprecipitable actin-AUBP complexes in the detergent-resistant cytoplasmic subfractions of lymphocytes. We show that cytochalasin-induced changes in AUBP activities are parallel with their higher binding affinity to RNA containing AU-rich instability sequence element as judged by in vitro competition and in vivo ultraviolet-crosslinking analysis. Correlation of these findings with changes in mRNA stability indicates that the actin cytoskeleton may play a physiologically important role in posttranscriptional regulation of lymphokine gene expression during early lymphocyte activation.

Actin Cytoskeleton↗

PubMed1997

The pathogenetic role of heme in pregnancy-induced hypertension-like disease in ewes.

Toxicosis syndrome of fasting pregnant ewes has a close similarity to human preeclampsia (hypertension, albuminuria). The common etiological factor might be oxidative hemolysis and heme-induced endothelial damage. Ewes (5 starving, 5 control) at 130-135 gestational days with a 96-h fasting period followed by refeeding were used. Blood pressure, platelet count, electrolytes, kidney and liver function parameters, as well as plasma glucose, hemoglobin/heme, free thiol groups and Trolox equivalent antioxidant capacity, and plasma iron and ferritin levels were measured. Statistical significance was assessed using Student's t test (P < 0.05). Besides hypertension and renal disturbances, hemolysis, elevated liver enzymes and low platelet count, characteristic of human HELLP syndrome, were also present. In the first 24 h of glucose deprivation there was a significant rise in both the plasma hemoglobin/heme and indirect bilirubin concentrations. The antioxidant free thiol levels decreased significantly the next day, without any change in the total antioxidant capacity of the plasma. While the loss of calcium and magnesium levels related to the similarity to preeclampsia, reduced plasma iron concentrations referred to species differences in iron homeostasis. An oxidative stress causing hemolysis in a glucose-6-phosphate dehydrogenase-deficient animal model was proven by the loss of free thiols after glucose deprivation. The activation of the oxidative stress protein heme oxygenase was a signal of endothelial cell injury, the primary cause of pregnancy-induced hypertension.

Animals↗

PubMed1997

Loss of pacing-induced preconditioning in rat hearts: role of nitric oxide and cholesterol-enriched diet.

We examined whether the inhibition of nitric oxide (NO) synthesis by NG-nitro-L-arginine (lNNA) abolished pacing-induced preconditioning, and if prolonged exposure to cholesterol-enriched diet led to the loss of preconditioning due to decreased cardiac NO formation. Therefore, Wistar rats fed 2% cholesterol-enriched diet or standard diet for 24 weeks were treated with a single dose of 1 mg/kg lNNA or its solvent at the end of the week 24, respectively. Isolated hearts from all groups were subjected to either preconditioning induced by three consecutive periods of pacing at 600 beats/min for 5 min, with 5-min interpacing periods, or time-matched non-preconditioning perfusion, followed by a 10-min coronary occlusion, respectively. In the control group, coronary occlusion after a non-preconditioning protocol decreased aortic flow (AF) from 45.4+/-2.4 to 15.6+/-1.5 ml/min, and resulted in a lactate dehydrogenase (LDH) release of 219+/-55 mU/min/g, however, preconditioning attenuated the consequences of coronary occlusion [AF: 27.3+/-1.7 ml/min (P<0.05); LDH: 44+/-14 mU/min/g (P<0.05)]. Preconditioning did not confer protection in the lNNA-treated (AF: 17.4+/-1.5 ml/min; LDH: 151+/-21 mU/min/g), and/or in the high-cholesterol-fed groups (AF: 15.7+/-1.2 ml/min; LDH: 168+/-22 mU/min/g). Preconditioning was preserved however, when hearts were treated with lNNA after the preconditioning protocol [AF: 29.6+/-2.2 ml/min (P<0.05); LDH: 48+/-17 mU/min/g (P<0.05)]. Both lNNA treatment and cholesterol-enriched diet markedly decreased cardiac NO content assayed by electron spin resonance spectroscopy. We conclude that NO may be involved in the triggering mechanism of pacing-induced preconditioning, the protective effect of which is blocked by sustained exposure to dietary cholesterol, possibly by influencing cardiac metabolism of NO.

Animals↗

PubMed1997

Moyamoya with arterial anomalies: relevance to pathogenesis.

We report five patients with moyamoya associated with arterial anomalies, including five aneurysms, one with ectasia of the parent artery, a basilar artery fenestration and an arteriovenous malformation. Possible pathogenetic factors for moyamoya are discussed, and a prenatal origin is suggested.

Adult↗

PubMed1997

Characterization of the early region 4 of porcine adenovirus type 3.

The nucleotide sequence of a 3028 bp DNA segment, located between map co-ordinates 100 and 92 in the genome of porcine adenovirus type 3 (PAV-3), was determined. The segment includes the entire early region 4 (E-4) and the right inverted terminal repeat sequences. There were two TATA boxes and one canonical polyadenylation signal on the 1 strand. Homology searches of the GenBank data base for the predicted amino acid sequences revealed that, of the eight open reading frames (ORFs) on the 1 strand, and four ORFs on the r strand, only ORF 8 on the 1 strand showed homology with the 34 kDa E-4 protein of human adenovirus types 2, 12 and 34. Northern blot analysis showed that transcription from the E-4 region of PAV-3 began 4 h after infection, peaked at 8 h and declined after 10 h, before DNA replication began 16 h after infection. The E-4 region of PAV-3 was further characterized by 5' and 3' end mapping of the transcription unit.

Adenoviridae↗