Search PubMed⌕ Search

Biomedical subjects

E Nagy

Publications and source records attributed to E Nagy.

At least 145 records · Page 8Linked to original sources

Prevention of congenital toxoplasmosis in Szeged, Hungary.

BACKGROUND: Toxoplasma gondii infection of the fetus can only be discovered or prevented by the appropriate serological screening and subsequent treatment of the mother and her offspring. In Hungary, there is no obligatory toxoplasma screening for pregnant women and both the reporting and follow-up of congenital toxoplasmosis cases is limited. In 1987 we started a systematic study in the Szeged region of Hungary, in which all pregnant women were screened and appropriate treatment given to all mothers and their offspring where congenital toxoplasmosis was suspected. METHODS: All pregnant women were routinely screened within the first 16 weeks of gestation for toxoplasma antibodies by complement fixation test (CFT). Seronegative cases were retested for possible seroconversion every second month. Patients with CFT titres > or = 1:256 were retested for anti-P30 immunoglobulin A (IgA), IgM and IgG antibodies by ELISA and/or SDS-PAGE-Western immunoblot in order to distinguish the acute and chronic phases of the infection. RESULTS: Up to the end of 1994, the sera of 17,735 gravidae were screened. Ten women were found to have seroconverted during pregnancy and 78 had high initial antibody levels accompanied by anti-P30 IgA antibodies at the very first screening. These two groups together were considered as definitely (10) or possibly (78) infected with Toxoplasma during pregnancy and were treated with Spiramycin. All of their offspring were also treated for one month and followed-up by systematic serological and clinical screening for 2 years. No congenital toxoplasmosis was found in any of the offspring. CONCLUSIONS: Antenatal, early diagnosis and treatment of toxoplasmosis in mothers, together with treatment and follow-up of their offspring, may considerably reduce the incidence of the disease in the offspring.

Animals↗

Prevalence of Chlamydia trachomatis infection in a low-risk population in Hungary.

BACKGROUND AND OBJECTIVE: Chlamydia trachomatis is the leading cause of nongonococcal urethritis and cervicitis in women. Because of the recent increases in the numbers of new cases and severe consequences, there is an urgent demand for the introduction of sensitive and specific rapid diagnostic methods. GOAL: A multicenter examination involving seven centers was sponsored by the Hungarian Ministry of Health and Welfare in order to provide a survey of Chlamydia trachomatis in the gravid population. 6,161 women were tested between 1994 to 1995. STUDY DESIGN: The seven centers were selected with regard to different aspects, from developed and less developed areas in the capital, two large provincial towns, and various other provincial regions reflecting either an industrial or an agricultural background. The nucleic acid hybridization method (PACE 2 Gen-Probe, San Diego, CA) was introduced in this low-risk population for the examination of Chlamydia trachomatis. In one center, a further two methods, antigen detection by ELISA (SYVA, CA) and cultivation on the McCoy cell line (staining with SYVA FITC-labeled antichlamydia monoclonal antibody), were applied. RESULTS: International surveys and experience indicate that the proportion of the population threatened by Chlamydia trachomatis is above 10%. The overall average incidence of Chlamydia trachomatis cases in this low-risk gravid population was 5.74%. The data from the different centers ranged between 1.6% and 9.7%. The chlamydia-infected Hungarian gravid population is below the critical 10%, but there is one Hungarian county where the value is close to 10%. CONCLUSIONS: In this provincial, industrial area, the number of unmarried and divorced gravida in a low economic situation is disproportionately high. For this disadvantaged population, permanent Chlamydia trachomatis screening was suggested. In the other centers, screening of pregnant women for Chlamydia trachomatis and the treatment of positive cases and their partners were suggested for pathological gravida with preterm labor and preterm rupture of the membranes.

Adult↗

Restriction endonuclease analysis of equine herpesvirus-1 isolates recovered in Ontario, 1986-1992, from aborted, stillborn, and neonatal foals.

Ninety-two equine herpesvirus type 1 isolates were recovered from aborted, stillborn, or neonatal foals from Ontario, Canada, from 1986 to 1992. From this total, 32 strains were randomly chosen for further study. Four or 5 isolates from each winter were selected, each from a different premises, and characterized by restriction enzyme analysis using BamHI, KpnI, BglII, HindIII, and EcoRI. Additional isolates from 2 premises and from a zebra foal were also assessed. For the strains isolated in 1986 and 1989-1992, the DNA pattern of 18 strains was similar to that of type 1P (Kentucky D) for BamHI and KpnI. None of the 32 strains studied could be differentiated by HindIII or EcoRI. Using BglII, an inconsistent fragment pattern and distribution were observed. Of the 8 strains isolated in 1987 and 1988, 7 were assigned into the 1B prototype group. The geographic distribution of 17 type 1P and 12 1B isolates was random across southern Ontario. These findings suggest that both electropherotypes can be recovered from horses in Ontario. The patterns of the additional equine isolates from the same premises were identical. The zebra isolate was different from the prototype equine herpesvirus type 1 and type 4 patterns and from all other equine isolates.

Abortion, Veterinary↗

Complex Therapy of Neck-Related Tinnitus, Hypacusia, and Vertigo.

The authors report the strategy of examination and treatment in patients suffering from tinnitus, hypacusia, and vertigo. In addition to the customary examinations, a routine cervical radiological examination and hemorrheological examination are recommended. The authors propose appropriate complex treatment and report their experience.

Journal Article↗

[Experience gained from the organization of the first group of patients who benefited from liver transplantation].

The authors report in this ciency in the majority of the cases was alcohol abuse or article about their experiences, how could they select a small group of patients awaiting liver transplantation since September 1994. The cause of the liver insuffiHCV infection. During 37 weeks 3 liver transplantations were performed and 5 patients died on the waiting list. (15,6% of the patients on the waiting list.)

Adult↗

Neuroimmune mechanisms in health and disease: 2. Disease.

In the second part of their article on the emerging field of neuroimmunology, the authors present an overview of the role of neuroimmune mechanisms in defence against infectious diseases and in immune disorders. During acute febrile illness, immune-derived cytokines initiate an acute phase response, which is characterized by fever, inactivity, fatigue, anorexia and catabolism. Profound neuroendocrine and metabolic changes take place: acute phase proteins are produced in the liver, bone marrow function and the metabolic activity of leukocytes are greatly increased, and specific immune reactivity is suppressed. Defects in regulatory processes, which are fundamental to immune disorders and inflammatory diseases, may lie in the immune system, the neuro endocrine system or both. Defects in the hypothalamus-pituitary-adrenal axis have been observed in autoimmune and rheumatic diseases, chronic inflammatory disease, chronic fatigue syndrome and fibromyalgia. Prolactin levels are often elevated in patients with systemic lupus erythematosus and other autoimmune diseases, whereas the bioactivity of prolactin is decreased in patients with rheumatoid arthritis. Levels of sex hormones and thyroid hormone are decreased during severe inflammatory disease. Defective neural regulation of inflammation likely plays a pathogenic role in allergy and asthma, in the symmetrical form of rheumatoid arthritis and in gastrointestinal inflammatory disease. A better understanding of neuroimmunoregulation holds the promise of new approaches to the treatment of immune and inflammatory diseases with the use of hormones, neurotransmitters, neuropeptides and drugs that modulate these newly recognized immune regulators.

Acquired Immunodeficiency Syndrome↗

Neuroimmune mechanisms in health and disease: 1. Health.

A novel scientific discipline that examines the complex interdependence of the neural, endocrine and immune systems in health and disease has emerged in recent years. In health, the neuroimmunoregulatory network is fundamental to host defence and to the transfer of immunity to offspring; the network also plays important roles in intestinal physiology and in tissue regeneration, healing and reproduction. The proliferation of lymphocytes in primary lymphoid organs (bone marrow, bursa of Fabricius [in birds] and thymus) and in secondary lymphoid organs (spleen, lymph nodes and mucosal lymphoid tissue) depends on prolactin and growth hormone. These hormones allow immune cells to respond to antigen and to soluble mediators, called cytokines. Immune-derived cytokines are capable of inducing fever and of altering neuro-transmitter activity in the brain and hormone secretion by the pituitary gland. The activation of the hypothalamus-pituitary-adrenal axis by cytokines leads to immunosuppression. Lymphoid organs are innervated, and tissue mast cells respond to neurologic stimuli. In general, acetylcholine and substance P exert immunostimulatory and proinflammatory effects, whereas epinephrine and somatostatin are immunosuppressive and anti-inflammatory. In this article, the authors predict that novel approaches to immunomodulation will be possible by altering the level or efficacy of immunoregulatory hormones and neurotransmitters.

Humans↗

Anti-estrogens enhance the therapeutic effect of lymphokine-activated killer cells on the P815 murine mastocytoma.

Tamoxifen (TX) and toremifene (TO) enhanced the lysis of P815 mastocytoma cells in vitro by syngeneic DBA2 spleen cells that have been activated by human recombinant interleukin-2 (IL-2) for 6 days (lymphokine-activated killer [LAK] cells). Similarly, enhanced tumor suppression occurred when TX- or TO-treated P815 cells were mixed with LAK cells and injected s.c. into normal DBA2 recipients. Tumor suppression could be increased further by treating such recipients orally with TX or TO and by the repeated injections of LAK cells into the tumor site. The treatment of animals bearing tumors (5 mm in diameter) orally with TX or TO or with LAK cells i.p. resulted in tumor suppression. When the drug treatment was combined with LAK cells, tumor suppression was more pronounced, and complete tumor regression was induced in a significant number of the animals so treated. Our results indicate that the immunotherapeutic effect of LAK cells can be significantly amplified by combined treatment with the anti-estrogens TX or TO.

Analysis of Variance↗

Modulation of lymphokine-activated killer cell-mediated cytotoxicity by estradiol and tamoxifen.

The effect of tamoxifen (TX) and estradiol (E2) on interleukin-2 (IL-2 )-activated killer (LAK) cell-mediated cytotoxicity was examined using spleen cells of Fischer 344 rats as the source of effectors and P815 murine mastocytoma cells as targets. Treatment of target cells with either TX or E2 for 4 or 18 hr rendered them highly sensitive to LAK cell-mediated lysis. When TX and E2 were applied jointly, cytotoxicity remained at the level of TX alone. The cytotoxic potential of IL-2-primed LAK cells was not modified consistently by TX and E2. When TX-treated target and effector cells were combined, high cytotoxicity characteristic of sensitized target cells was observed. In similar experiments with E2-treated cells, both enhancement and inhibition of cytotoxicity by treated effector cells was seen in some designs. Target cells could be sensitized for LAK cell-mediated destruction by physiological concentrations (1 nM) of E2 and equimolar concentration of TX. Sensitization led to the accelerated release of the nuclear label 3H-thymidine from target cells after cytotoxic insult and could be prevented by treatment with the metabolic inhibitors cycloheximide and actinomycin D. Enhanced 3H-thymidine release from TX-treated targets was also demonstrated after induction of Ca2+ influx by exposure to the ionophore A23187. Neither E2 nor TX exerted a direct cytotoxic effect on P815 cells. P815 cells had no classical receptors for E2 or progesterone.

Animals↗

[Effect of vaccination on the risk of hepatitis B infection in hospital personnel].

The effect of vaccination on acute B hepatitis, on HBsAg carrier state and on the seropositivity of hepatitis B virus was examined in the personnel of the St. László Hospital in two periods. Human plasma origin vaccine was introduced gradually from 1985 to 1989. From 1989 till the end of 1994 recombinant vaccines were provided for all workers. A total of 10577 tests were done from 3524 sera of 2019 hospital workers. A total of 2.4% of the workers developed acute hepatitis. Hepatitis B was confirmed most frequently (29%) of hepatitis cases. In the first and second period HBsAg positivity was 4.1% and 2.1% (P = 0.1), respectively. Although the annual frequency of acute hepatitis has not changed, that of HBsAg positivity showed a decreasing tendency during the nine years of the study. The prevalence of hepatitis B markers could be characterized by a significant rise in close correlation with age. The protective effect of vaccination is markedly reflected by the altered prevalence of hepatitis B virus markers in the different age groups. At the age of fifty and above hepatitis B seropositivity was 47.2% and 36.4% in the first and second period (P = 0.1), respectively. The frequency of seropositivity was the highest among the workers of surgical, pathological, hepatological departments and ICU. Our results show that vaccination is an effective tool in hepatitis B prevention. Every effort has to be made to promote hepatitis B immunity to all health care workers and strictly follow hygienic preventive measures.

Adult↗

[Molecular biology of thyroid diseases].

Recent developments in molecular biology and the accessibility of techniques for clinical research have led to a better understanding of the background of common thyroid diseases. The cloning and sequencing of the thyroid stimulating hormone receptor, thyroid peroxidase and thyroglobulin, and the characterization of the protein-DNA interaction during thyroid hormone action, as well as the discovery of intracellular signal transduction pathways were the most important steps which resulted in new diagnostic and therapeutic approaches. New explanations of thyroid autoimmune processes are being investigated.

Genes, Tumor Suppressor↗

Single-step purification of recombinant wild-type and mutant HIV-1 reverse transcriptase.

We have devised a single-step method that enables purification of HIV-1 recombinant reverse transcriptase directly from bacterial lysates in less than 2 h. Clarified lysates are applied to commercial Q- and S-matrix cartridge columns connected in series. The columns are washed with low-salt buffer to remove unbound protein, then the Q column is removed and reverse transcriptase is eluted from the S column using a salt gradient. The purification has been carried out with both medium-pressure and high-pressure chromatographic systems. Purifications are carried out at room temperature near neutral pH, providing enzyme with high DNA polymerase specific activity. A crucial aspect of the procedure is the use of Tris buffer, a buffer that is normally incompatible in cation-exchange methods. The method is applicable for the purification of the p51/p66 heterodimer and the p5l and p66 homodimer forms of reverse transcriptase. We have used this method to purify wild-type reverse transcriptase and several recombinant proteins containing mutations correlated with dideoxynucleoside drug resistance.

Blotting, Western↗

dsRNA associated with virus-like particles in Eimeria spp. of the domestic fowl.

RNA segments, identified as double-stranded, were found in sporozoites of the Guelph strains of Eimeria acervulina, E. brunetti, E. maxima and E. necatrix and in 8 of 11 strains of E. acervulina obtained from poultry houses across the United States. These RNAs were resistant to RNase A digestion in the presence of high salt concentrations (0.3 M NaCl). On agarose-gel electrophoresis, E. acervulina had one obvious band at 1.7 kb and a faint band at 3.5 kb; E. brunetti had two bands at 2.1 and 3.3 kb, respectively; E. maxima had one band at 4.5 kb; and E. necatrix had two major bands at 4.5 and 5.6 kb, respectively. No dsRNA band was seen in the three strains of E. tenella examined. Virus-like particles were purified by cesium chloride density centrifugation of homogenates of E. necatrix sporulated oocysts. The fraction at peak virus concentration had a buoyant density of 1.39 g ml-1. These virus-like particles were icosahedral, had no envelope and measured 42-44 nm in diameter. Only one RNA band at 5.6 kb was observed when nucleic acids from gradient fractions containing virus were subjected to electrophoresis. The 4.5-kb dsRNA segment of E. necatrix was not associated with a virus-like particle.

Animals↗

Porcine adenoviruses types 1, 2 and 3 have short and simple early E-3 regions.

The nucleotide sequence of the E-3 region genes, the hexon associated protein pVIII genes, and part of the fiber genes coding for the N-terminal tail regions, of porcine adenovirus (PAV) types 1 and 2 were determined. The sizes of the E-3 regions were found to be 1162 and 1222 bp, respectively. The five open reading frames (ORF) encoded within the sequenced regions of PAV types 1 and 2 shared a high degree of homology with the published sequences of the corresponding ORFs of PAV-3. The E-3 regions of PAV types 1, 2 and 3 were further characterized by Northern blot analysis and 5' and 3' end mapping of the transcripts by S1 nuclease analysis. The results of these experiments indicated that the E-3 regions in these three viruses are shorter and simpler in organization than the E-3 regions of human adenoviruses. A potential promoter for the E-3 regions of these PAVs was identified.

Adenovirus E3 Proteins↗

Molecular cloning and restriction enzyme mapping of avian adenovirus type 8 DNA.

Avian adenovirus (AAV) type 8 was cultured in an avian hepatoma cell line designated CH-SAH and the viral DNA extracted and purified. Restriction enzyme analysis of viral DNA using the endonucleases ApaI, EcoRI, HindIII, KpnI, NotI, SpeI, StuI and XbaI was carried out, and fragments representing the entire genome were cloned. According to the restriction enzyme fragments, the size of the AAV type 8 genome was calculated to be 44.7 kb. Subcloning of viral DNA fragments and hybridization studies using selected viral DNA fragments facilitated the construction of the physical map of AAV type 8 DNA.

Animals↗

The immune effects of neuropeptides.

Current evidence indicates that the neuroendocrine system is the highest regulator of immune/inflammatory reactions. Prolactin and growth hormone stimulate the production of leukocytes, including lymphocytes, and maintain immunocompetence. The hypothalamus-pituitary-adrenal axis constitutes the most powerful circuit regulating the immune system. The neuropeptides constituting this axis, namely corticotrophin releasing factor, adrenocorticotrophic hormone, alpha-melanocyte stimulating hormone, and beta-endorphin are powerful immunoregulators, which have a direct regulatory effect on lymphoid cells, regulating immune reactions by the stimulation of immunoregulatory hormones (glucocorticoids) and also by acting on the central nervous system which in turn generates immunoregulatory nerve impulses. Peptidergic nerves are major regulators of the inflammatory response. Substance P and calcitonin gene-related peptide are pro-inflammatory mediators and somatostatin is anti-inflammatory. The neuroendocrine regulation of the inflammatory response is of major significance from the point of view of immune homeostasis. Malfunction of this circuit leads to disease and often is life-threatening. The immune system emits signals towards the neuroendocrine system by cytokine mediators which reach significant blood levels (cytokine-hormones) during systemic immune/inflammatory reactions. Interleukin-1, -6, and TNF-alpha are the major cytokine hormones mediating the acute phase response. These cytokines induce profound neuroendocrine and metabolic changes by interacting with the central nervous system and with many other organs and tissues in the body. Corticotrophin releasing factor functions under these conditions as a major co-ordinator of the response and is responsible for activating the ACTH-adrenal axis for regulating fever and for other CNS effects leading to a sympathetic outflow. Increased ACTH secretion leads to glucocorticoid production. alpha-melanocyte stimulating hormone functions under these conditions as a cytokine antagonist and an anti-pyretic hormone. The sympathetic outflow, in conjunction with increased adrenal activity. leads to the elevation of catecholamines in the bloodstream and in tissues. Current evidence suggests that neuroimmune mechanisms are essential in normal physiology, such as tissue turnover, involution, atrophy, intestinal function, and reproduction. Host defence against infection, trauma and shock relies heavily on the neuroimmunoregulatory network. Moreover, abnormalities of neuroimmunoregulation contribute to the aetiology of autoimmune disease, chronic inflammatory disease, immunodeficiency, allergy, and asthma. Finally, neuroimmune mechanisms play an important role in regeneration and healing.

Animals↗