Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Tamás Gáll is active.

Publication


Featured researches published by Tamás Gáll.


Oral Microbiology and Immunology | 2009

Progressive increase of human papillomavirus carriage rates in potentially malignant and malignant oral disorders with increasing malignant potential

Krisztina Szarka; Ildikó Tar; Enikő Fehér; Tamás Gáll; Andrea Kis; E. D. Tóth; Róbert Boda; Ildikó Márton; Lajos Gergely

INTRODUCTION We investigated the potential role of human papillomaviruses (HPVs) in potentially malignant oral disorders, oral leukoplakia (OL) and oral lichen planus (OLP), and in oral squamous cell cancer (OSCC) in an Eastern Hungarian population with a high incidence of OSCC. METHODS Excised tumor samples (65 OSCC patients) and exfoliated cells from potentially malignant lesions (from 44 and 119 patients with OL and OLP, respectively) as well as from healthy controls (72 individuals) were analysed. OLPs were classified based on clinical appearance, 61 patients had erosive-atrophic lesions (associated with higher malignancy risk, EA-OLP) and 58 had non-erosive non-atrophic lesions (with lower risk of becoming malignant, non-EA-OLP), respectively. Exfoliated cells collected from apparently healthy mucosa accompanied each lesion sample. HPV was detected by MY/GP polymerase chain reaction (PCR) and genotyped by restriction analysis of amplimers. Copy numbers in lesions were determined using real-time PCR. Prevalence rates, copy number distributions, and association with risk factors and diseases were analysed using chi-square test, t-test, and logistic regression, respectively. RESULTS We detected HPVs significantly more frequently in lesions than in controls (P < or = 0.001 in all comparisons). HPV prevalence increased gradually with increasing severity of lesions (32.8, 40.9, and 47.7% in OLP, OL, and OSCC, respectively). Copy number distribution patterns roughly corresponded to prevalence rates, but OLP and OL were comparable. HPV prevalence differed significantly between EA-OLP and non-EA-OLP groups (42.6 vs. 22.4%); EA-OLP group showed a prevalence similar to that found in OL. CONCLUSION HPVs may be involved in the development or progression of not only OSCC but also of potentially malignant oral lesions.


European Journal of Oral Sciences | 2009

Epstein-Barr virus prevalence in oral squamous cell cancer and in potentially malignant oral disorders in an eastern Hungarian population

Andrea Kis; Enikő Fehér; Tamás Gáll; Ildikó Tar; Róbert Boda; Etelka D. Tóth; Gábor Méhes; Lajos Gergely; Krisztina Szarka

We tested 65, 44, and 116 patients with oral squamous cell cancer (OSCC), oral leukoplakia (OL), and oral lichen planus (OLP) against 68 age-matched controls for the presence of Epstein-Barr virus (EBV). Apparently healthy mucosa was simultaneously sampled and examined in all patients. Paraffin-embedded tissue sections of all EBV-positive patients with OSCC were examined for latent membrane protein-1 (LMP-1) expression (demonstrable in most EBV-associated malignancies) using immunohistochemistry. The prevalence of EBV in the controls and in OSCC, OL, and OLP lesions was 19.1%, 73.8%, 29.5%, and 46.6%, respectively, and 66.2%, 22.7%, and 31.9% in the healthy mucosa of patients, respectively. The prevalence of EBV in OSCC patients was significantly higher than in controls or in respective samples of the other two patient groups both in the lesion and in the healthy mucosa. Comparisons including only patients with EBV-negative lesions yielded similar results. Lesions of patients with OLP, but not of patients with OL, differed significantly from controls in EBV prevalence. In OSCC, LMP-1 expression was not detected, and EBV carriage was not significantly associated with any risk factors and did not influence the outcome. Although a high prevalence of EBV was found in OSCC, comparable carriage rates on healthy mucosa of patients indicated that an aetiological role of EBV is unlikely.


Brain Behavior and Evolution | 2004

A possible stimulatory effect of FMRFamide on neural nitric oxide production in the central nervous system of Helix lucorum L.

Tamás Röszer; Zsolt Jenei; Tamás Gáll; Olivér Nagy; Zsolt Czimmerer; Zoltán Serfozo; Károly Elekes; Gaspar Banfalvi

The anatomical and functional relationship between neurons expressing nitric oxide (NO) synthase and molluscan cardioexcitatory (FMRFamide)-like neuropeptides was studied in the central ganglia of Helix lucorum (Pulmonata, Gastropoda), applying NADPHdiaphorase (NADPHd) histochemistry to visualize NO synthase and immunocytochemistry to demonstrate FMRFamide (FMRFa) at the light microscopic level. The NO production of the ganglia was detected by the colorimetric Griess determination of nitrite, a breakdown product of NO. Effects of the NO synthase substrate amino acid L-arginine, the NO synthase inhibitor Nω-nitro-L-arginine (NOARG), synthetic FMRFa and the FMRFa sensitive ion channel blocker amiloride hydrochloride on nitrite production were also tested. NADPHd reaction labeled nerve cells and fibers in the procerebra, mesocerebra and metacerebra within the cerebral ganglia, and cell clusters in the postcerebral ganglia. FMRFa immunolabeling could be observed within subpopulations of NADPHd positive cells and in pericellular varicose fibers surrounding NADPHd stained neurons. Nitrite production of the ganglia was stimulated by L-arginine (10– 20 mM) but was decreased by NOARG (1–2 mM). Synthetic FMRFa (0.830–3.340 mM) increased the nitrite production in a dose dependent manner, but was ineffective in the presence of NOARG. Amiloride hydrochloride (7.890 mM) reduced the FMRFa evoked nitrite production in all ganglia. This is the first description of an anatomical relationship between putative NO producing and FMRFa containing cells, suggesting a possible regulatory role of FMRFa in the NO mediated signaling in an invertebrate nervous system.


Toxicology and Applied Pharmacology | 2013

In vivo application of a small molecular weight antifungal protein of Penicillium chrysogenum (PAF)

Zoltán Palicz; Agnes Jenes; Tamás Gáll; Kornél Miszti-Blasius; Sándor Kollár; Ilona Kovács; Miklós Emri; Teréz Márián; Éva Leiter; István Pócsi; Éva Csősz; Gergő Kalló; Csaba Hegedűs; László Virág; László Csernoch; Péter Szentesi

The antifungal protein of Penicillium chrysogenum (PAF) inhibits the growth of important pathogenic filamentous fungi, including members of the Aspergillus family and some dermatophytes. Furthermore, PAF was proven to have no toxic effects on mammalian cells in vitro. To prove that PAF could be safely used in therapy, experiments were carried out to investigate its in vivo effects. Adult mice were inoculated with PAF intranasally in different concentrations, up to 2700 μg·kg⁻¹ daily, for 2 weeks. Even at the highest concentration--a concentration highly toxic in vitro for all affected molds used, animals neither died due to the treatment nor were any side effects observed. Histological examinations did not find pathological reactions in the liver, in the kidney, and in the lungs. Mass spectrometry confirmed that a measurable amount of PAF was accumulated in the lungs after the treatment. Lung tissue extracts from PAF treated mice exerted significant antifungal activity. Small-animal positron emission tomography revealed that neither the application of physiological saline nor that of PAF induced any inflammation while the positive control lipopolysaccharide did. The effect of the drug on the skin was examined in an irritative dermatitis model where the change in the thickness of the ears following PAF application was found to be the same as in control and significantly less than when treated with phorbol-12-myristate-13-acetate used as positive control. Since no toxic effects of PAF were found in intranasal application, our result is the first step for introducing PAF as potential antifungal drug in therapy.


Journal of Medical Virology | 2009

Investigation of the occurrence of torque tenovirus in malignant and potentially malignant disorders associated with human papillomavirus

Enikő Fehér; Tamás Gáll; Melinda Murvai; Andrea Kis; Róbert Boda; Tamás Sápy; Ildikó Tar; Lajos Gergely; Krisztina Szarka

In a previous pilot study, a significantly poorer outcome of laryngeal cancer was found in patients co‐infected with human papillomavirus (HPV) and genogroup 1 torque tenovirus (TTV). The present study aimed to collect data on the overall prevalence of TTVs on the prevalence of genogroup 1 TTV in two other malignancies associated with HPV, oral squamous cell cancer and cervical cancer, and in oral and cervical premalignant lesions (oral lichen planus, oral leukoplakia, cervical atypia). Oral samples from all patients were accompanied with a sample from the healthy mucosa. The overall prevalence of TTV was significantly higher both in oral squamous cell cancer and cervical cancer compared with other patient groups or with the respective controls. The prevalence of genogroup 1 TTV was significantly higher in lesions of oral squamous cell cancer and oral lichen planus, but not in lesions of oral leukoplakia (24.6%, 10.1%, and 4.5%, respectively), compared with the prevalence in the oral cavity of controls (1.4%). Co‐infection rates with genogroup 1 TTV and HPV were significantly higher in oral squamous cell cancer than in controls, oral lichen planus or oral leukoplakia patients (12.3%, 0.0%, 6.7%, and 4.5%, respectively). The prevalence of genogroup 1 TTV in all cervical samples were comparable. These data suggest that genogroup 1 TTV may be associated specifically with some head and neck mucosal disorders, but disproves a (co)carcinogenic role in oral cancer or cervical cancer as well as an association with HPV or with malignancies associated with HPV. J. Med. Virol. 81:1975–1981, 2009.


Virology Journal | 2011

Dominance of variant A in Human Herpesvirus 6 viraemia after renal transplantation

Eszter Csoma; Beáta Mészáros; Tamás Gáll; László Asztalos; József Kónya; Lajos Gergely

BackgroundHuman herpesvirus 6 (HHV-6), mostly variant B reactivation in renal transplant patients has been published by other authors, but the pathogenetic role of HHV-6 variant A has not been clarified. Our aims were to examine the prevalence of HHV-6, to determine the variants, and to investigate the interaction between HHV-6 viraemia, human cytomegalovirus (HCMV) infection and clinical symptoms.MethodsVariant-specific HHV-6 nested PCR and quantitative real-time PCR were used to examine blood samples from renal transplant patients and healthy blood donors for the presence and load of HHV-6 DNA and to determine the variants. Active HHV-6 infection was proved by RT-PCR, and active HCMV infection was diagnosed by pp65 antigenaemia test.ResultsHHV-6 viraemia was significantly more frequent in renal transplant patients compared to healthy blood donors (9/200 vs. 0/200; p = 0.004), while prevalence of HHV-6 latency was not significantly different (13/200 vs. 19/200; p > 0.05). Dominance of variant A was revealed in viraemias (8/9), and the frequency of HHV-6A was significantly higher in active infections compared with latency in renal transplant patients (8/9 vs. 2/13; p = 0.0015). Latency was established predominantly by HHV-6B both in renal transplant patients and in healthy blood donors (11/13 and 18/19). There was no statistical significant difference in occurrence of HCMV and HHV-6 viraemia in renal transplant patients (7/200 vs. 9/200). Statistical analysis did not reveal interaction between HHV-6 viraemia and clinical symptoms in our study.ConclusionsContrary to previous publications HHV-6A viraemia was found to be predominant in renal transplant patients. Frequency of variant A was significantly higher in cases of active infection then in latency.


Antiviral Research | 2011

Virological failure of intralesional cidofovir therapy in recurrent respiratory papillomatosis is not associated with genetic or epigenetic changes of HPV11: complete genome comparison of sequential isolates.

Tamás Gáll; Andrea Kis; Enikő Fehér; Lajos Gergely; Krisztina Szarka

Five sequential human papillomavirus type 11 (HPV11) positive samples collected from an aggressive juvenile onset recurrent respiratory papillomatosis before, during and after intralesional cidofovir therapy leading to virological failure after initial response were analyzed. Sequencing of the complete genome as well as methylation analysis by bisulfate modification and sequencing of the long control region (LCR) were performed to seek for genetic and epigenetic changes as a possible background for therapy failure. Single-strand conformation polymorphism of E1, E2, E6, E7 and LCR was used to exclude the presence of multiple HPV11 infection. All five complete genomes were identical and all four E2 binding sites in the LCR were uniformly unmethylated in all five genomes. Thus the virological failure was not due to virological factors suggesting that cidofovir action may depend more heavily on the host.


Emerging microbes & infections | 2016

Application of a low molecular weight antifungal protein from Penicillium chrysogenum (PAF) to treat pulmonary aspergillosis in mice

Zoltán Palicz; Tamás Gáll; Éva Leiter; Sándor Kollár; Ilona Kovács; Kornél Miszti-Blasius; István Pócsi; László Csernoch; Péter Szentesi

PAF, a small antifungal protein from Penicillium chrysogenum, inhibits the growth of several pathogenic filamentous fungi, including members of the Aspergillus genus. PAF has been proven to have no toxic effects in vivo in mice by intranasal application. To test its efficacy against invasive pulmonary aspergillosis (IPA), experiments were carried out in mice suffering from IPA. Adult mice were immunosuppressed and then infected with Aspergillus fumigatus. After stable infection, the animals were inoculated with PAF intranasally at a concentration of 2.7 mg/kg twice per day. At this concentration—which is highly toxic in vitro to A. fumigatus—the mortality of the animals was slightly delayed but finally all animals died. Histological examinations revealed massive fungal infections in the lungs of both PAF-treated and untreated animal groups. Because intranasally administered PAF was unable to overcome IPA, modified and combined therapies were introduced. The intraperitoneal application of PAF in animals with IPA prolonged the survival of the animals only 1 day. Similar results were obtained with amphotericin B (AMB), with PAF and AMB being equally effective. Combined therapy with AMB and PAF—which are synergistic in vitro—was found to be more effective than either AMB or PAF treatment alone. As no toxic effects of PAF in mammals have been described thus far, and, moreover, there are so far no A. fumigatus strains with reported inherent or acquired PAF resistance, it is worth carrying out further studies to introduce PAF as a potential antifungal drug in human therapy. Emerging Microbes & Infections (2016) 5, e114; doi:10.1038/emi.2016.116; published online 9 November 2016


Medical Microbiology and Immunology | 2013

Genomic differences in the background of different severity in juvenile-onset respiratory papillomatoses associated with human papillomavirus type 11

Tamás Gáll; Andrea Kis; Tímea Zsófia Tatár; Gábor Kardos; Lajos Gergely; Krisztina Szarka

This study aimed to compare complete genome sequences of human papillomavirus (HPV) type 11 from two solitary papillomas (considered minimally aggressive), two moderately (six and nine episodes) and two highly aggressive (30 and 33 episodes) juvenile-onset respiratory papillomatoses. Genomic regions were sequenced using the Sanger method; sequences were compared to available GenBank genomes. Activity of the long control region (LCR) was assessed in HEp-2 cell line using luciferase assays and compared to that of the reference (GenBank Accession Number M14119). Site-directed mutagenesis was performed to confirm the association of polymorphisms with differences in LCR activity. Eleven alterations resulted in amino acid changes in different open reading frames. A72E in E1 and Q86K in E2 proteins were exclusively present in a moderately aggressive disease, L1 alterations A476V and S486F were unique to a severe papillomatosis. HPV11s in both solitary papillomas had identical LCRs containing a T7546C polymorphism, which strongly attenuated LCR activity, as confirmed by site-directed mutagenesis. This strong attenuator polymorphism was also present in the other four genomes showing significantly higher activities, but in these other alterations with demonstrable but statistically not significant attenuating (A7413C, 7509 T deletion) or enhancing (C7479T, T7904A) effect on transactivating potential (as demonstrated by site-directed mutagenesis) were also detected. LCR activities corresponded well to severity, excepting the highly aggressive papillomatosis with the L1 alterations. Presence of intratypic variants cannot explain differences in severity of respiratory papillomatoses associated with HPV11; virulence seems to be determined by the interaction of multiple genetic differences.


Acta Microbiologica Et Immunologica Hungarica | 2011

Comparison of diversity of torque teno virus 1 in different mucosal tissues and disorders

Enikő Fehér; Gábor Kardos; Tamás Gáll; Andrea Kis; Lajos Gergely; Krisztina Szarka

Diversity of TTV1 was assessed in the head and neck region in patients with potentially malignant (oral lichen planus, oral leukoplakia) and malignant lesions (oral and laryngeal squamous cell cancers) and was compared to that found in the uterine cervix (cervical atypia and cervical cancer) by directly sequencing the NG061-063 segment of ORF1. These sequences were classified by the formerly used genogroup-genotype system as well as by the newly accepted species classification by aligning with the corresponding region of the type sequences of the 29 TTV species. All sequences obtained during the study clustered together with the TTV1 type sequence; to express diversity within TTV1, genotypes and subtypes of the former classification were used.The commonest subtypes were 2c followed by 2b, 1a and 1b. Subtypes 2b and 2c were evenly distributed among cervical samples; subtype 1a was more frequent in patients with cervical atypia or cancer. Subtypes 2c was more frequent than 2b in head and neck lesions. In conclusion, genotype and even subtype distribution may be important in association with diseases, therefore using this classification for characterization of intraspecies diversity of TTV1 is proposed.

Collaboration


Dive into the Tamás Gáll's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Andrea Kis

University of Debrecen

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Ildikó Tar

University of Debrecen

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Éva Leiter

University of Debrecen

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge