39 results on '"Németh V"'
Search Results
2. Advantages and Limitation of Lab-on-a-chip Technique in the Analysis of Wheat Proteins
- Author
-
Balázs, G., Tömösközi, S., Harasztos, A., Németh, V., Tamás, Á., Morgounov, A., Belan, I., Ma, W., and Békés, F.
- Published
- 2012
3. 290 Immune alterations of response to anti-PD-1 therapy in melanoma-preliminary results
- Author
-
Németh, V., primary, Hunyadi, K., additional, Gyulai, R., additional, and Lengyel, Z., additional
- Published
- 2021
- Full Text
- View/download PDF
4. The use of transcranial direct current stimulation in stroke rehabilitation: effects on mood and cognition
- Author
-
Szépfalusi, N., primary, Németh, V., additional, Kazinczi, C., additional, Holczer, A., additional, Vékony, T., additional, Csifcsák, G., additional, Jakab, K., additional, Vécsei, L., additional, and Must, A., additional
- Published
- 2019
- Full Text
- View/download PDF
5. High-Resolution Seismic Imaging Using a 2C Land Streamer System
- Author
-
Szabþ, T., primary, Toth, T., additional, Hamori, Z., additional, Németh, V., additional, and Filipszki, P., additional
- Published
- 2019
- Full Text
- View/download PDF
6. 124 Investigation of the circadian system in psoriasis
- Author
-
Németh, V., Á Kinyó, Horváth, S., Gyulai, R., and Lengyel, Z.
- Published
- 2021
- Full Text
- View/download PDF
7. Serological survey of hantavirus infection among rodents in Hungary
- Author
-
Madai, M., primary, Németh, V., additional, Oldal, M., additional, Horváth, G., additional, Herczeg, R., additional, Pintér, R., additional, Kutas, A., additional, Dallos, B., additional, Bányai, K., additional, and Jakab, F., additional
- Published
- 2016
- Full Text
- View/download PDF
8. West Nile virus surveillance in mosquitoes, April to October 2013, Vojvodina province, Serbia: implications for the 2014 season
- Author
-
Kemenesi, G, primary, Krtinić, B, additional, Milankov, V, additional, Kutas, A, additional, Dallos, B, additional, Oldal, M, additional, Somogyi, N, additional, Németh, V, additional, Bányai, K, additional, and Jakab, F, additional
- Published
- 2014
- Full Text
- View/download PDF
9. Novel European lineages of bat astroviruses identified in Hungary
- Author
-
KEMENESI, G., primary, DALLOS, B., additional, GÖRFÖL, T., additional, BOLDOGH, S., additional, ESTÓK, P., additional, KURUCZ, K., additional, OLDAL, M., additional, NÉMETH, V., additional, MADAI, M., additional, BÁNYAI, K., additional, and JAKAB, F., additional
- Published
- 2014
- Full Text
- View/download PDF
10. Interesting conformational and substitutional disorder in the crystal structures of three homologous crowns
- Author
-
Böcskei, Zs., primary, Simon, K., additional, Németh, V., additional, Ágai, B., additional, and Tőke, L., additional
- Published
- 1996
- Full Text
- View/download PDF
11. POSITRON ANNIHILATION AND MÖSSBAUER STUDIES OF ZrxFe1-x AMORPHOUS AND CRYSTALLINE ALLOYS
- Author
-
BALOGH, A., BALOGH, J., DEZSI, I., NEMETH, V., ENGELMANN, H., GHAFARI, M., and GONSER, U.
- Published
- 1985
- Full Text
- View/download PDF
12. Monitoring Changes in the Antimicrobial-Resistance Gene Set (ARG) of Raw Milk and Dairy Products in a Cattle Farm, from Production to Consumption.
- Author
-
Kerek Á, Németh V, Szabó Á, Papp M, Bányai K, Kardos G, Kaszab E, Bali K, Nagy Z, Süth M, and Jerzsele Á
- Abstract
Raw milk and dairy products can serve as potential vectors for transmissible bacterial, viral and protozoal diseases, alongside harboring antimicrobial-resistance genes. This study monitors the changes in the antimicrobial-resistance gene pool in raw milk and cheese, from farm to consumer, utilizing next-generation sequencing. Five parallel sampling runs were conducted to assess the resistance gene pool, as well as phage or plasmid carriage and potential mobility. In terms of taxonomic composition, in raw milk the Firmicutes phylum made up 41%, while the Proteobacteria phylum accounted for 58%. In fresh cheese, this ratio shifted to 93% Firmicutes and 7% Proteobacteria. In matured cheese, the composition was 79% Firmicutes and 21% Proteobacteria. In total, 112 antimicrobial-resistance genes were identified. While a notable reduction in the resistance gene pool was observed in the freshly made raw cheese compared to the raw milk samples, a significant growth in the resistance gene pool occurred after one month of maturation, surpassing the initial gene frequency. Notably, the presence of extended-spectrum beta-lactamase (ESBL) genes, such as OXA-662 (100% coverage, 99.3% identity) and OXA-309 (97.1% coverage, 96.2% identity), raised concerns; these genes have a major public health relevance. In total, nineteen such genes belonging to nine gene families ( ACT , CMY , EC , ORN , OXA , OXY , PLA , RAHN , TER ) have been identified. The largest number of resistance genes were identified against fluoroquinolone drugs, which determined efflux pumps predominantly. Our findings underscore the importance of monitoring gene pool variations throughout the product pathway and the potential for horizontal gene transfer in raw products. We advocate the adoption of a new approach to food safety investigations, incorporating next-generation sequencing techniques.
- Published
- 2024
- Full Text
- View/download PDF
13. "…in the middle of nowhere…" Access to, and quality of, services for autistic adults from parents' perspectives: a qualitative study.
- Author
-
Németh V, Győri M, Ehmann B, Völgyesi-Molnár M, and Stefanik K
- Abstract
Introduction: Adequate education, employment, and services for autistic individuals contribute significantly to their and their parents' quality of life. Services and support for adults are dramatically more limited than those for children. The main purpose of this study was to explore how parents perceive factors supporting/hindering access to services, and how they assess the quality of services., Methods: Qualitative data provided by 12 parents via a semi-structured interview with a broader focus on parental quality of life and its factors were analyzed. Their autistic children were between 20 and 34 years of age. A thematic analysis was performed on parts of the narratives on their adult periods of life., Results: A complex pattern of parental perception of supportive and hampering factors influencing access to services unfolded. The sparsity of services/activities and reliable information on them made the space for autonomous decisions on service take highly limited. Parents have modest expectations on quality of services, evaluating them along two key aspects: a safe, positive atmosphere, and communication between parents and professionals. Other aspects of individualized autism-specific support were not or just rarely mentioned., Discussion: Parents perceive themselves as investing a lot of effort and resources in getting some form of regular service and/or activity for their adult child. However, these parental efforts often fail, their child becoming inactive, and dependent on their presence. This suggests system-level problems with services for autistic adults in Hungary, with literature showing it is not specific to this country., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Németh, Győri, Ehmann, Völgyesi-Molnár and Stefanik.)
- Published
- 2024
- Full Text
- View/download PDF
14. Hemizygous nonsense variant in the moesin gene (MSN) leads to a new autoimmune phenotype of Immunodeficiency 50.
- Author
-
Kovács AL, Kárteszi J, Prohászka Z, Kalmár T, Késmárky G, Koltai K, Nagy Z, Sebők J, Vas T, Molnár K, Berki T, Böröcz K, Gyömörei C, Szalma J, Egyed M, Horváth S, Oláh P, Csuka D, Németh V, and Gyulai R
- Subjects
- Cryoglobulins, Humans, Lupus Coagulation Inhibitor, Male, Microfilament Proteins, Phenotype, RNA, Messenger, Antiphospholipid Syndrome, Hashimoto Disease genetics, Tooth Loss
- Abstract
Here, we present the findings of an investigation involving two male siblings with juvenile total tooth loss, early-onset chronic leg ulcers, and autoimmune thyroiditis, as well as focal segmental glomerulosclerosis with associated pulmonary emphysema in one and diabetes mellitus in the other. The clinical picture and lupus anticoagulant, cryoglobulin, and cold agglutinin positivity suggested the diagnosis of antiphospholipid syndrome. Flow cytometry analysis showed immunophenotypes consistent with immune dysregulation: a low number of naive T cells, elevated CD4
+ T cell counts, and decreased CD8+ T-cell counts were detected, and more than half of the T-helper population was activated. Considering the siblings' almost identical clinical phenotype, the genetic alteration was suspected in the background of the immunodeficiency. Whole exome sequencing identified a previously not described hemizygous nonsense variant (c.650G>A, p.W217X) within exon 6 of the moesin ( MSN ) gene localized on chromosome X, resulting in significantly decreased MSN mRNA expression compared to healthy controls. We present a putative new autoimmune phenotype of Immunodeficiency 50 (MIM300988) characterized by antiphospholipid syndrome, Hashimoto's thyroiditis, leg ulcers, and juvenile tooth loss, associated with W217X mutation of the MSN gene., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Kovács, Kárteszi, Prohászka, Kalmár, Késmárky, Koltai, Nagy, Sebők, Vas, Molnár, Berki, Böröcz, Gyömörei, Szalma, Egyed, Horváth, Oláh, Csuka, Németh and Gyulai.)- Published
- 2022
- Full Text
- View/download PDF
15. Population snapshot of the extended-spectrum β-lactamase-producing Escherichia coli invasive strains isolated from a Hungarian hospital.
- Author
-
Tóth K, Tóth Á, Kamotsay K, Németh V, and Szabó D
- Subjects
- Escherichia coli genetics, Escherichia coli Infections diagnosis, Escherichia coli Infections epidemiology, Escherichia coli Proteins genetics, Hospitals, Humans, Hungary epidemiology, Incidence, Multilocus Sequence Typing, Prevalence, Anti-Bacterial Agents pharmacology, Escherichia coli isolation & purification, Escherichia coli Infections drug therapy, beta-Lactamases genetics
- Abstract
Background: This study was carried out to determine the prevalence and the genetic background of extended-spectrum β-lactamase-producing Escherichia coli invasive isolates obtained from a tertiary-care hospital in Budapest, Hungary., Methods: Between October-November 2018, all invasive ESBL-producing E. coli isolates were collected from Central Hospital of Southern Pest. The antimicrobial susceptibility testing was performed according to the EUCAST guidelines. The possible clonal relationships were investigated by core genome (cg)MLST (SeqSphere +) using whole-genome sequencing (WGS) data of isolates obtained from Illumina 251-bp paired-end sequencing. From WGS data acquired antimicrobial resistance genes, virulence genes and replicon types were retrieved using ResFinder3.1, PlasmidFinder2.1, pMLST-2.0, VirulenceFinder2.0 and Virulence Factors Database online tools., Results: Overall, six E. coli isolates proved to be resistant to third-generation cephalosporins and ESBL-producers in the study period. Full genome sequence analysis showed that five E. coli isolates belonged to the ST131 clone: two to C1-M27 subclade with bla
CTX-M-27 and three to C2/H30Rx subclade with blaCTX-M-15 . One isolate belonged to ST1193 with blaCTX-M-27 . According to cgMLST, all C2/H30Rx isolates formed a cluster (≤ 6 allele differences), while the blaCTX-M-27 -producing C1-M27 isolates differed at least 35 alleles from each other. Both C2/H30Rx and C1-M27 ST131 isolates harbored similar antimicrobial resistance gene sets. However, only C2/H30Rx isolates had the qnrB and aac(3)-IIa. The isolates carried similar extraintestinal virulence gene set but differed in some genes encoding siderophores, protectins and toxins. Moreover, only one C2/H30Rx isolate carried salmochelin siderophore system and showed virotype B. All isolates showed resistance against ceftriaxone, cefotaxime, and ciprofloxacin, and the C2/H30Rx isolates were also resistant to gentamicin, tobramycin, and ceftazidime., Conclusions: Out of six ESBL-producing E. coli, five belonged to the ST131 clone. This study indicates, that the C2/H30Rx and C1-M27 subclades of the ST131 appear to be the dominant clones collected in a Hungarian hospital., (© 2022. The Author(s).)- Published
- 2022
- Full Text
- View/download PDF
16. Expression Patterns of Clock Gene mRNAs and Clock Proteins in Human Psoriatic Skin Samples.
- Author
-
Németh V, Horváth S, Kinyó Á, Gyulai R, and Lengyel Z
- Subjects
- Adult, Cell Line, Cytokines genetics, Down-Regulation genetics, Epidermis metabolism, HaCaT Cells, Humans, Inflammation genetics, Inflammation metabolism, Keratinocytes metabolism, Psoriasis metabolism, CLOCK Proteins genetics, Circadian Rhythm genetics, Psoriasis genetics, RNA, Messenger genetics, Skin metabolism
- Abstract
Psoriasis is a systemic inflammatory skin disorder that can be associated with sleep disturbance and negatively influence the daily rhythm. The link between the pathomechanism of psoriasis and the circadian rhythm has been suggested by several previous studies. However, there are insufficient data on altered clock mechanisms in psoriasis to prove these theories. Therefore, we investigated the expression of the core clock genes in human psoriatic lesional and non-lesional skin and in human adult low calcium temperature (HaCaT) keratinocytes after stimulation with pro-inflammatory cytokines. Furthermore, we examined the clock proteins in skin biopsies from psoriatic patients by immunohistochemistry. We found that the clock gene transcripts were elevated in psoriatic lesions, especially in non-lesional psoriatic areas, except for rev-erbα , which was consistently downregulated in the psoriatic samples. In addition, the REV-ERBα protein showed a different epidermal distribution in non-lesional skin than in healthy skin. In cytokine-treated HaCaT cells, changes in the amplitude of the bmal1 , cry1 , rev-erbα and per1 mRNA oscillation were observed, especially after TNFα stimulation. In conclusion, in our study a perturbation of clock gene transcripts was observed in uninvolved and lesional psoriatic areas compared to healthy skin. These alterations may serve as therapeutic targets and facilitate the development of chronotherapeutic strategies in the future.
- Published
- 2021
- Full Text
- View/download PDF
17. Temporal Dynamics of Two Pathogenic Hantaviruses Among Rodents in Hungary.
- Author
-
Madai M, Németh V, Oldal M, Horváth G, Herczeg R, Kelemen K, Kemenesi G, and Jakab F
- Subjects
- Animals, Female, Hungary epidemiology, Male, Seasons, Time Factors, Arvicolinae, Orthohantavirus isolation & purification, Murinae
- Abstract
Hantaviruses are worldwide pathogens, which often cause serious or even fatal diseases in humans. Hosts are predominantly in the form of rodents and soricomorphs; however, bats are also described as an important reservoir. In Hungary, representatives of two human pathogenic species of the genus Orthohantavirus are present: the Dobrava-Belgrade orthohantavirus and Puumala orthohantavirus. In Hungarian forests, the dominant rodent species are Apodemus flavicollis , Apodemus agrarius , Apodemus sylvaticus , and Myodes glareolus , all of which are natural reservoirs comprising different hantaviruses. The aim of the study was to survey the prevalence of hantaviruses among rodent populations and examine the potential relationship regarding population densities, years, sex, and seroprevalence. Rodents were trapped at 13 sampling plots in a forest reserve located in the Mecsek Mountain range, Hungary, from March to October between 2011 and 2014. Rodent serum samples were tested for IgG antibodies against Dobrava-Belgrade virus and Puumala virus by enzyme-linked immunosorbent assay (ELISA) using a recombinant nucleocapsid protein. During the 4-year sampling period, 2491 specimens were tested and 254 (10.2%) proved seropositive for orthohantaviruses. In 2011, the seroprevalence among Apodemus spp. and M. glareolus was 17.2% (114/661) and 3.9% (3/77), respectively, although this rate had reversed itself in 2014. Seropositivity was substantiated in 18.4% (12/65) of Myodes voles, while only 3.6% (13/359) of the tested Apodemus rodents were found to be IgG positive. Seroconversion was observed in 58 cases, while seroreversion was only detected in 3 individual cases. A significant difference among the number of infected males and females was identified in the first 2 years of our study. Winter survival with respect to rodents was not negatively affected due to the hantavirus infection. Hantavirus seroprevalence was not directly influenced by host abundance. Consequently, we assume that high rodent density alone does not lead to an increased risk of hantavirus infection among the rodent host population.
- Published
- 2020
- Full Text
- View/download PDF
18. Serologic survey of the Crimean-Congo haemorrhagic fever virus infection among wild rodents in Hungary.
- Author
-
Földes F, Madai M, Németh V, Zana B, Papp H, Kemenesi G, Bock-Marquette I, Horváth G, Herczeg R, and Jakab F
- Subjects
- Animals, Female, Hemorrhagic Fever, Crimean epidemiology, Hemorrhagic Fever, Crimean virology, Hungary epidemiology, Male, Prevalence, Rodent Diseases virology, Seroepidemiologic Studies, Arvicolinae, Hemorrhagic Fever Virus, Crimean-Congo isolation & purification, Hemorrhagic Fever, Crimean veterinary, Murinae, Rodent Diseases epidemiology
- Abstract
Crimean-Congo haemorrhagic fever virus (CCHFV) is a tick-borne pathogen, which causes an increasing number of severe infections in many parts of Africa, Asia and in Europe. The virus is primarily transmitted by ticks, however, the spectrum of natural hosts regarding CCHFV includes a wide variety of domestic and wild animals. Although the presence of CCHFV was hypothesized in Hungary, data in support of CCHFV prevalence has thus far, proven insufficient. In the present study, rodents belonging to four species, the yellow-necked mouse (Apodemus flavicollis), the striped field mouse (A. agrarius), the wood mouse (A. sylvaticus) and the bank vole (Myodes glareolus), were all systematically trapped in the Mecsek Mountain region (Southwest Hungary), from 2011 through 2013. Rodent sera were collected and screened for CCHFV antibodies with dot-blot pre-screening and immunofluorescence assay. Among the 2085 tested rodents, 20 (0.96%) were positive for IgG antibody against CCHFV. Seroprevalence was the highest (1.25%) in A. flavicollis serum samples. Distinctly, we now provide the first data regarding CCHFV occurrence and seroprevalence among wild rodents in Hungary. This observation represents a need for large-scale surveillance to effectively assess the enzootic background and the potential public health risk of CCHFV in Hungary., (Copyright © 2019 Elsevier GmbH. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
19. [Diagnostic challenges in pediatric cow’s milk protein allergy].
- Author
-
Lendvai-Emmert D, Emmert V, Fusz K, Prémusz V, Németh V, Ligetvári R, and Tóth GP
- Subjects
- Animals, Cattle, Child, Child, Preschool, Female, Food Hypersensitivity, Humans, Immunoglobulin E blood, Infant, Infant, Newborn, Male, Milk Proteins immunology, Predictive Value of Tests, Sensitivity and Specificity, Skin Tests methods, Allergens immunology, Immunoglobulin E immunology, Milk Hypersensitivity diagnosis, Milk Hypersensitivity immunology, Milk Proteins adverse effects
- Abstract
Introduction and aim: The aim of our research is to evaluate and compare commonly performed diagnostic tests, and to examine the psychological disorders induced by this food allergy. Children with symptoms suggesting cow's milk protein allergy were included in this study (n = 47). Blood and saliva samples were collected from the participants. Parents were asked to fill in a questionnaire constructed by the research team (containing the DSM-5 symptoms checklist about attention deficit hyperactivity disorder). Method: One of the most widely used diagnostic tool is the skin allergy test, which was performed in 47 subjects (n = 47, mean age: 7.36 years); only 2 children showed positive test result for cow's milk. Lymphocyte transformation test was observed to be positive in 8 children (17%), 4 subjects demonstrated questionable results. In our sub-study about psychological symptoms (n = 43, mean age: 7.88 years), the score was according to the attention deficit hyperactivity disorder symptom checklist before the diet (6.88, SD: 4.43) and showed significant decrease after 3 months of the elimination diet (4.48, SD: 3.69, p = 0.001). Scores of children with sleep disorder (10.62, SD: 4.23) also represented a significant reduction after 3 months of the diet (6.69, SD: 4.59, p = 0.009). Salivary cortisol levels did not show significant changes before and after elimination diet. Results: According to our data, skin allergy testing and lymphocyte transformation test are not reliable diagnostic tools for establishing the diagnosis. Conclusion: We conclude that a significant improvement in clinical symptoms can only be achieved with a strict elimination diet. Orv Hetil. 2019; 160(33): 1311-1318.
- Published
- 2019
- Full Text
- View/download PDF
20. Microglia control the spread of neurotropic virus infection via P2Y12 signalling and recruit monocytes through P2Y12-independent mechanisms.
- Author
-
Fekete R, Cserép C, Lénárt N, Tóth K, Orsolits B, Martinecz B, Méhes E, Szabó B, Németh V, Gönci B, Sperlágh B, Boldogkői Z, Kittel Á, Baranyi M, Ferenczi S, Kovács K, Szalay G, Rózsa B, Webb C, Kovacs GG, Hortobágyi T, West BL, Környei Z, and Dénes Á
- Subjects
- Animals, Brain virology, Mice, Microglia virology, Neurons metabolism, Neurons virology, Brain metabolism, Herpesviridae Infections metabolism, Microglia metabolism, Monocytes metabolism, Receptors, Purinergic P2Y12 metabolism, Signal Transduction physiology
- Abstract
Neurotropic herpesviruses can establish lifelong infection in humans and contribute to severe diseases including encephalitis and neurodegeneration. However, the mechanisms through which the brain's immune system recognizes and controls viral infections propagating across synaptically linked neuronal circuits have remained unclear. Using a well-established model of alphaherpesvirus infection that reaches the brain exclusively via retrograde transsynaptic spread from the periphery, and in vivo two-photon imaging combined with high resolution microscopy, we show that microglia are recruited to and isolate infected neurons within hours. Selective elimination of microglia results in a marked increase in the spread of infection and egress of viral particles into the brain parenchyma, which are associated with diverse neurological symptoms. Microglia recruitment and clearance of infected cells require cell-autonomous P2Y12 signalling in microglia, triggered by nucleotides released from affected neurons. In turn, we identify microglia as key contributors to monocyte recruitment into the inflamed brain, which process is largely independent of P2Y12. P2Y12-positive microglia are also recruited to infected neurons in the human brain during viral encephalitis and both microglial responses and leukocyte numbers correlate with the severity of infection. Thus, our data identify a key role for microglial P2Y12 in defence against neurotropic viruses, whilst P2Y12-independent actions of microglia may contribute to neuroinflammation by facilitating monocyte recruitment to the sites of infection.
- Published
- 2018
- Full Text
- View/download PDF
21. Serologic survey of orthopoxvirus infection among rodents in hungary.
- Author
-
Oldal M, Sironen T, Henttonen H, Vapalahti O, Madai M, Horváth G, Dallos B, Kutas A, Földes F, Kemenesi G, Németh V, Bányai K, and Jakab F
- Subjects
- Animals, Arvicolinae, Disease Reservoirs, Female, Humans, Hungary epidemiology, Male, Mice, Murinae, Orthopoxvirus isolation & purification, Poxviridae Infections epidemiology, Poxviridae Infections virology, Rodent Diseases virology, Rodentia, Seroepidemiologic Studies, Surveys and Questionnaires, Antibodies, Viral blood, Orthopoxvirus immunology, Poxviridae Infections veterinary, Rodent Diseases epidemiology
- Abstract
As a result of discontinuing vaccination against smallpox after the late 1970s, different orthopoxviruses (OPVs), such as cowpox virus (CPXV), have become a re-emerging healthcare threat among zoonotic pathogens. In Hungary, data on OPV prevalence among its rodent host species have been absent. Here, rodents belonging to four species, i.e., striped field mouse (Apodemus agrarius), yellow-necked mouse (A. flavicollis), wood mouse (A. sylvaticus) and bank vole (Myodes glareolus), were live trapped at 13 sampling plots on a 149-ha area in the Mecsek Mountains, Hungary, from March to September in 2011 and 2012. Rodent sera were collected and screened for OPV-reactive antibodies with an immunfluorescence assay (IFA). Among the 1587 tested rodents, 286 (18.0%) harbored OPV-specific antibodies. Seroprevalence was the highest for the bank vole (71.4%) and the striped field mouse (66.7%). Due to a masting event in the autumn of 2011 across Central Europe, the abundance of bank voles increased drastically in the 2012 season, raising the overall OPV seroprevalence. We provide the first data on OPV occurrence and seroprevalence in rodents in Hungary. The circulation of OPV in rodents in densely populated areas warrants further studies to elucidate the zoonotic potential of OPV in humans.
- Published
- 2015
- Full Text
- View/download PDF
22. Putative novel lineage of West Nile virus in Uranotaenia unguiculata mosquito, Hungary.
- Author
-
Kemenesi G, Dallos B, Oldal M, Kutas A, Földes F, Németh V, Reiter P, Bakonyi T, Bányai K, and Jakab F
- Abstract
West Nile virus (WNV) is an increasing public health concern in Europe with numerous human cases. A total of 23,029 female mosquitoes were tested for a variety of mosquito-borne flaviviruses and orthobunyaviruses supposedly endemic in Southern Transdanubia, Hungary, in the frames of a large-scale surveillance between 2011 and 2013. WNV nucleic acid was detected in a single pool containing Uranotaenia unguiculata mosquitoes. Sequence- and phylogenetic analyses for two different regions (NS5 and E) of the viral genome showed that the novel Hungarian WNV strain was different from other previously described WNV lineages. These findings may indicate the presence of a putative, novel lineage of WNV in Europe. Our results also indicate that U. unguiculata mosquito may become relevant species as a potential vector for West Nile virus in Europe.
- Published
- 2014
- Full Text
- View/download PDF
23. Molecular survey of RNA viruses in Hungarian bats: discovering novel astroviruses, coronaviruses, and caliciviruses.
- Author
-
Kemenesi G, Dallos B, Görföl T, Boldogh S, Estók P, Kurucz K, Kutas A, Földes F, Oldal M, Németh V, Martella V, Bányai K, and Jakab F
- Subjects
- Animals, Astroviridae classification, Astroviridae genetics, Astroviridae isolation & purification, Base Sequence, Caliciviridae classification, Caliciviridae genetics, Caliciviridae isolation & purification, Coronavirus classification, Coronavirus genetics, Coronavirus isolation & purification, Hungary epidemiology, Phylogeny, Prevalence, RNA Virus Infections epidemiology, RNA Virus Infections virology, RNA Viruses isolation & purification, Real-Time Polymerase Chain Reaction, Chiroptera virology, RNA Virus Infections veterinary, RNA Viruses classification, RNA Viruses genetics
- Abstract
Unlabelled: Background: Bat-borne viruses pose a potential risk to human health and are the focus of increasing scientific interest. To start gaining information about bat-transmitted viruses in Hungary, we tested multiple bat species for several virus groups between 2012 and 2013., Materials and Methods: Fecal samples were collected from bats across Hungary. We performed group-specific RT-PCR screening for astro-, calici-, corona-, lyssa-, othoreo-, paramyxo-, and rotaviruses. Positive samples were selected and sequenced for further phylogenetic analyses., Results: A total of 447 fecal samples, representing 24 European bat species were tested. Novel strains of astroviruses, coronaviruses, and caliciviruses were detected and analyzed phylogenetically. Out of the 447 tested samples, 40 (9%) bats were positive for at least one virus. Bat-transmitted astroviruses (BtAstV) were detected in eight species with a 6.93% detection rate (95% confidence interval [CI] 4.854, 9.571). Coronaviruses (BtCoV) were detected in seven bat species with a detection rate of 1.79% (95% CI 0.849, 3.348), whereas novel caliciviruses (BtCalV) were detected in three bat species with a detection rate of 0.67% (95% CI 0.189, 1.780). Phylogenetic analyses revealed a great diversity among astrovirus strains, whereas the Hungarian BtCoV strains clustered together with both alpha- and betacoronavirus strains from other European countries. One of the most intriguing findings of our investigation is the discovery of novel BtCalVs in Europe. The Hungarian BtCalV did not cluster with any of the calcivirus genera identified in the family so far., Conclusions: We have successfully confirmed BtCoVs in numerous bat species. Furthermore, we have described new bat species harboring BtAstVs in Europe and found new species of CalVs. Further long-term investigations involving more species are needed in the Central European region for a better understanding on the host specificity, seasonality, phylogenetic relationships, and the possible zoonotic potential of these newly described viruses.
- Published
- 2014
- Full Text
- View/download PDF
24. Highly potent dUTPase inhibition by a bacterial repressor protein reveals a novel mechanism for gene expression control.
- Author
-
Szabó JE, Németh V, Papp-Kádár V, Nyíri K, Leveles I, Bendes AÁ, Zagyva I, Róna G, Pálinkás HL, Besztercei B, Ozohanics O, Vékey K, Liliom K, Tóth J, and Vértessy BG
- Subjects
- Bacterial Proteins antagonists & inhibitors, Genomic Islands, Pyrophosphatases antagonists & inhibitors, Pyrophosphatases genetics, Repressor Proteins antagonists & inhibitors, Staphylococcus aureus enzymology, Staphylococcus aureus metabolism, Bacterial Proteins metabolism, Gene Expression Regulation, Bacterial, Pyrophosphatases metabolism, Repressor Proteins metabolism, Staphylococcus aureus genetics
- Abstract
Transfer of phage-related pathogenicity islands of Staphylococcus aureus (SaPI-s) was recently reported to be activated by helper phage dUTPases. This is a novel function for dUTPases otherwise involved in preservation of genomic integrity by sanitizing the dNTP pool. Here we investigated the molecular mechanism of the dUTPase-induced gene expression control using direct techniques. The expression of SaPI transfer initiating proteins is repressed by proteins called Stl. We found that Φ11 helper phage dUTPase eliminates SaPIbov1 Stl binding to its cognate DNA by binding tightly to Stl protein. We also show that dUTPase enzymatic activity is strongly inhibited in the dUTPase:Stl complex and that the dUTPase:dUTP complex is inaccessible to the Stl repressor. Our results disprove the previously proposed G-protein-like mechanism of SaPI transfer activation. We propose that the transfer only occurs if dUTP is cleared from the nucleotide pool, a condition promoting genomic stability of the virulence elements., (© The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.)
- Published
- 2014
- Full Text
- View/download PDF
25. Serosurvey of pathogenic hantaviruses among forestry workers in Hungary.
- Author
-
Oldal M, Németh V, Madai M, Pintér R, Kemenesi G, Dallos B, Kutas A, Sebők J, Horváth G, Bányai K, and Jakab F
- Subjects
- Adolescent, Adult, Aged, Antibodies, Viral blood, Blotting, Western, Female, Hantavirus Infections blood, Hantavirus Infections virology, Humans, Hungary epidemiology, Male, Middle Aged, Occupational Diseases blood, Occupational Diseases virology, Seroepidemiologic Studies, Forestry, Hantavirus Infections epidemiology, Occupational Diseases epidemiology
- Abstract
Objectives: The aim of the study was to survey the prevalence of human hantavirus infections among forestry workers, who are considered a risk population for contracting the disease. Sera collected from volunteers were tested for antibodies against Dobrava-Belgrade (DOBV) and Puumala (PUUV) viruses., Material and Methods: For serological analyses, full capsid proteins of DOBV and PUUV viruses were produced in a bacterial expression system, while Ni-resin was used for protein purification. Samples were screened for anti-hantavirus antibodies by ELISA, results were confirmed by Western blot analysis., Results: A total of 835 samples collected from 750 males and 85 females were tested by indirect ELISA and positive test results were confirmed by Western blot assay. Out of the 45 ELISA-reactive samples, 38 were confirmed by Western blot analysis. The regional distribution of seropositive individuals was as follows: 1.9% (2/107) in the Danube-Tisza Plateau (Great Plains), 3.1% (10/321) in the Southern Transdanubian region, 5.2% (13/248) in the Northern Transdanubian, and 8.2% (13/159) in the North Hungarian Mountains., Conclusions: Our data show marked geographic differences in seroprevalence of pathogenic hantaviruses within Hungary, indicating elevated exposure to hantavirus infections in some areas.
- Published
- 2014
- Full Text
- View/download PDF
26. Molecular detection and phylogenetic analysis of tick-borne encephalitis virus in rodents captured in the transdanubian region of Hungary.
- Author
-
Pintér R, Madai M, Horváth G, Németh V, Oldal M, Kemenesi G, Dallos B, Bányai K, and Jakab F
- Subjects
- Animals, Arvicolinae virology, Encephalitis Viruses, Tick-Borne classification, Encephalitis, Tick-Borne epidemiology, Epidemiological Monitoring, Hungary epidemiology, Murinae virology, Phylogeny, Reverse Transcriptase Polymerase Chain Reaction, Encephalitis Viruses, Tick-Borne genetics, Encephalitis Viruses, Tick-Borne isolation & purification, Encephalitis, Tick-Borne virology, Rodent Diseases epidemiology, Rodentia virology
- Abstract
Abstract Tick-borne encephalitis virus (TBEV) infection is a common zoonotic disease affecting humans in Europe and Asia. To determine whether TBEV is present in small mammalian hosts in Hungary, liver samples of wild rodents were tested for TBEV RNA. Over a period of 7 years, a total of 405 rodents were collected at five different geographic locations of the Transdanubian region. TBEV nucleic acid was identified in four rodent species: Apodemus agrarius, A. flavicollis, Microtus arvalis, and Myodes glareolus. Out of the 405 collected rodents, 17 small mammals (4.2%) were positive for TBEV. The present study provides molecular evidence and sequence data of TBEV from rodents in Hungary.
- Published
- 2014
- Full Text
- View/download PDF
27. Identification of hantavirus infection by Western blot assay and TaqMan PCR in patients hospitalized with acute kidney injury.
- Author
-
Oldal M, Németh V, Madai M, Kemenesi G, Dallos B, Péterfi Z, Sebők J, Wittmann I, Bányai K, and Jakab F
- Subjects
- Acute Kidney Injury pathology, Adult, Aged, Clinical Laboratory Techniques methods, Female, Hantavirus Infections virology, Hemorrhagic Fever with Renal Syndrome virology, Humans, Hungary, Male, Middle Aged, Young Adult, Acute Kidney Injury virology, Blotting, Western methods, Orthohantavirus isolation & purification, Hantavirus Infections diagnosis, Hemorrhagic Fever with Renal Syndrome diagnosis, Polymerase Chain Reaction methods, Puumala virus isolation & purification
- Abstract
Hantaviruses, one of the causative agents of viral hemorrhagic fevers, represent a considerable healthcare threat. In Hungary, Dobrava-Belgrade virus (DOBV) and Puumala virus (PUUV) are the main circulating hantavirus species, responsible for the clinical picture known as hemorrhagic fever with renal syndrome, a disease that may be accompanied by acute kidney injury (AKI), requiring hospitalization with occasionally prolonged recovery phase. A total of 20 patient sera were collected over a 2-year period from persons hospitalized with AKI, displaying clinical signs and laboratory findings directly suggestive for hantavirus infection. Samples were tested using an immunoblot assay, based on complete viral nucleocapsid proteins to detect patients' IgM and IgG antibodies against DOBV and PUUV. In parallel, all specimens were also tested by 1-step real-time TaqMan reverse-transcriptase polymerase chain reaction to confirm infection and to determine the causative hantavirus genotype. We present here the first Hungarian clinical study spanning across 2 years and dedicated specifically to assess acute kidney injuries, in the context of hantavirus prevalence., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
28. Catalytic mechanism of α-phosphate attack in dUTPase is revealed by X-ray crystallographic snapshots of distinct intermediates, 31P-NMR spectroscopy and reaction path modelling.
- Author
-
Barabás O, Németh V, Bodor A, Perczel A, Rosta E, Kele Z, Zagyva I, Szabadka Z, Grolmusz VI, Wilmanns M, and Vértessy BG
- Subjects
- Biocatalysis, Crystallography, X-Ray, Deoxyuracil Nucleotides chemistry, Deoxyuracil Nucleotides metabolism, Mason-Pfizer monkey virus enzymology, Nuclear Magnetic Resonance, Biomolecular, Phosphorus Isotopes, Protein Conformation, Pyrophosphatases metabolism, Models, Molecular, Phosphates chemistry, Pyrophosphatases chemistry
- Abstract
Enzymatic synthesis and hydrolysis of nucleoside phosphate compounds play a key role in various biological pathways, like signal transduction, DNA synthesis and metabolism. Although these processes have been studied extensively, numerous key issues regarding the chemical pathway and atomic movements remain open for many enzymatic reactions. Here, using the Mason-Pfizer monkey retrovirus dUTPase, we study the dUTPase-catalyzed hydrolysis of dUTP, an incorrect DNA building block, to elaborate the mechanistic details at high resolution. Combining mass spectrometry analysis of the dUTPase-catalyzed reaction carried out in and quantum mechanics/molecular mechanics (QM/MM) simulation, we show that the nucleophilic attack occurs at the α-phosphate site. Phosphorus-31 NMR spectroscopy ((31)P-NMR) analysis confirms the site of attack and shows the capability of dUTPase to cleave the dUTP analogue α,β-imido-dUTP, containing the imido linkage usually regarded to be non-hydrolyzable. We present numerous X-ray crystal structures of distinct dUTPase and nucleoside phosphate complexes, which report on the progress of the chemical reaction along the reaction coordinate. The presently used combination of diverse structural methods reveals details of the nucleophilic attack and identifies a novel enzyme-product complex structure.
- Published
- 2013
- Full Text
- View/download PDF
29. Molecular characterization of Dobrava and Kurkino genotypes of Dobrava-Belgrade hantavirus detected in Hungary and Northern Croatia.
- Author
-
Németh V, Oldal M, Madai M, Horváth G, Kemenesi G, Dallos B, Bányai K, and Jakab F
- Subjects
- Animals, Croatia, Genotype, Orthohantavirus classification, Orthohantavirus isolation & purification, Hantavirus Infections virology, Hungary, Mice, Molecular Sequence Data, Phylogeny, Orthohantavirus genetics, Hantavirus Infections veterinary, Rodent Diseases virology
- Abstract
Among the Hantavirus genus, Saaremaa virus (SAAV) has been the subject of taxonomical debates. While the International Committee on Taxonomy of Viruses declares SAAV as a distinct species, several European hantavirus experts proposed that SAAV is in fact a genotype of Dobrava-Belgrade virus (DOBV). In the present study we performed S-segment-based phylogenetic analysis of eight DOBV strains identified in rodents in Hungary and Northern Croatia. These new sequences considerably increase the number of complete nucleoprotein gene sequences deposited in the NCBI database. Our phylogenetic analysis clearly support the taxonomical nomenclature recently proposed for DOBV, i.e., genotypes such as Dobrava, Saaremaa, Kurkino, and Sochi should indeed be classified within the DOBV hantavirus species. Moreover, we found that only the Dobrava and Kurkino genotypes of DOBV species are circulating in Hungary while currently there is no evidence for the presence of Saaremaa genotype.
- Published
- 2013
- Full Text
- View/download PDF
30. Structure and enzymatic mechanism of a moonlighting dUTPase.
- Author
-
Leveles I, Németh V, Szabó JE, Harmat V, Nyíri K, Bendes ÁÁ, Papp-Kádár V, Zagyva I, Róna G, Ozohanics O, Vékey K, Tóth J, and Vértessy BG
- Subjects
- Amino Acid Sequence, Cations, Divalent metabolism, Magnesium metabolism, Models, Molecular, Molecular Sequence Data, Phylogeny, Protein Conformation, Sequence Alignment, Staphylococcus Phages chemistry, Staphylococcus aureus virology, Pyrophosphatases chemistry, Pyrophosphatases metabolism, Staphylococcus Phages enzymology
- Abstract
Genome integrity requires well controlled cellular pools of nucleotides. dUTPases are responsible for regulating cellular dUTP levels and providing dUMP for dTTP biosynthesis. In Staphylococcus, phage dUTPases are also suggested to be involved in a moonlighting function regulating the expression of pathogenicity-island genes. Staphylococcal phage trimeric dUTPase sequences include a specific insertion that is not found in other organisms. Here, a 2.1 Å resolution three-dimensional structure of a ϕ11 phage dUTPase trimer with complete localization of the phage-specific insert, which folds into a small β-pleated mini-domain reaching out from the dUTPase core surface, is presented. The insert mini-domains jointly coordinate a single Mg2+ ion per trimer at the entrance to the threefold inner channel. Structural results provide an explanation for the role of Asp95, which is suggested to have functional significance in the moonlighting activity, as the metal-ion-coordinating moiety potentially involved in correct positioning of the insert. Enzyme-kinetics studies of wild-type and mutant constructs show that the insert has no major role in dUTP binding or cleavage and provide a description of the elementary steps (fast binding of substrate and release of products). In conclusion, the structural and kinetic data allow insights into both the phage-specific characteristics and the generally conserved traits of ϕ11 phage dUTPase.
- Published
- 2013
- Full Text
- View/download PDF
31. Identification of tick-borne encephalitis virus in ticks collected in southeastern Hungary.
- Author
-
Pintér R, Madai M, Vadkerti E, Németh V, Oldal M, Kemenesi G, Dallos B, Gyuranecz M, Kiss G, Bányai K, and Jakab F
- Subjects
- Animals, Dermacentor virology, Encephalitis Viruses, Tick-Borne genetics, Encephalitis, Tick-Borne virology, Female, Humans, Hungary epidemiology, Larva, Male, Nymph, Phylogeny, Prevalence, RNA, Viral chemistry, RNA, Viral genetics, Seasons, Sequence Analysis, RNA, Arachnid Vectors virology, Encephalitis Viruses, Tick-Borne isolation & purification, Encephalitis, Tick-Borne epidemiology, Ixodes virology, Ixodidae virology
- Abstract
Tick-borne encephalitis virus (TBEV) is an arthropod-borne viral pathogen causing infections in Europe and is responsible for most arbovirus central nervous system infections in Hungary. Assessing the TBEV prevalence in ticks through detection of genomic RNA is a broadly accepted approach to estimate the transmission risk from a tick bite. For this purpose, 2731 ticks were collected from the neighboring area of the town of Dévaványa, located in southeastern Hungary, which is considered a low-risk-transmission area for TBEV. Altogether, 2300 ticks were collected from the vegetation, while 431 were collected from rodents. Samples were pooled and then screened for TBEV with a newly designed semi-nested RT-PCR (RT-snPCR) targeting the NS1 genomic region. PCR results were confirmed by direct sequencing of the second round amplicons. Among the 3 different collected tick species (Ixodes ricinus, Haemaphysalis concinna, Dermacentor marginatus), I. ricinus was the only species that tested positive for TBEV. TBEV-positive ticks were collected from small mammals or from the vegetation. One nymphal pool and 4 larval pools tested positive for TBEV. The only positive nymphal pool was unfed and came from vegetation, while ticks of the 4 positive larval pools were collected from rodents. Minimal TBEV prevalence in ticks was 0.08% for unfed nymphs and 0.78% for feeding larvae. Our results indicate that further long-term investigations on the occurrence of TBEV are needed to better describe the geographic distribution and the prevalence of infected ticks in Hungary., (Copyright © 2013 Elsevier GmbH. All rights reserved.)
- Published
- 2013
- Full Text
- View/download PDF
32. Serologic evidence of Crimean-Congo hemorrhagic fever virus infection in Hungary.
- Author
-
Németh V, Oldal M, Egyed L, Gyuranecz M, Erdélyi K, Kvell K, Kalvatchev N, Zeller H, Bányai K, and Jakab F
- Subjects
- Animals, CHO Cells, Cricetulus, Hemorrhagic Fever Virus, Crimean-Congo isolation & purification, Hemorrhagic Fever, Crimean diagnosis, Hemorrhagic Fever, Crimean epidemiology, Hemorrhagic Fever, Crimean virology, Humans, Hungary epidemiology, Immunoglobulin G blood, Public Health, Antibodies, Viral blood, Arachnid Vectors virology, Hares virology, Hemorrhagic Fever Virus, Crimean-Congo immunology, Hemorrhagic Fever, Crimean veterinary, Ixodidae virology
- Abstract
Crimean-Congo hemorrhagic fever virus (CCHFV) is a typical tick-borne pathogen that causes an increasing number of severe infections in many parts of Africa, Asia, the Middle East, and the Balkans, as well as in some other parts of Europe. The virus is transmitted primarily by Hyalomma spp., and the spectrum of natural hosts for CCHFV is broad, including wild and domestic animals. Although, the presence of CCHFV was hypothesized in Hungary, no significant research activity has been carried out in the past 30 years. In the present study, we provide serological evidence of CCHFV infection in Lepus europeus using newly developed antibody detection assays. Of 198 samples, 12 (6%) were positive for immunoglobulin G antibody against CCHFV, with 2 independent detection assays. This observation indicates a need for a large-scale surveillance to estimate the potential public health risk of CCHFV in Hungary.
- Published
- 2013
- Full Text
- View/download PDF
33. Collective motion of cells mediates segregation and pattern formation in co-cultures.
- Author
-
Méhes E, Mones E, Németh V, and Vicsek T
- Subjects
- Animals, Coculture Techniques, Diffusion, Embryonic Development, Fishes, Keratinocytes cytology, Microscopy, Video, Motion, Body Patterning, Cell Movement, Cell Separation
- Abstract
Pattern formation by segregation of cell types is an important process during embryonic development. We show that an experimentally yet unexplored mechanism based on collective motility of segregating cells enhances the effects of known pattern formation mechanisms such as differential adhesion, mechanochemical interactions or cell migration directed by morphogens. To study in vitro cell segregation we use time-lapse videomicroscopy and quantitative analysis of the main features of the motion of individual cells or groups. Our observations have been extensive, typically involving the investigation of the development of patterns containing up to 200,000 cells. By either comparing keratocyte types with different collective motility characteristics or increasing cells' directional persistence by the inhibition of Rac1 GTP-ase we demonstrate that enhanced collective cell motility results in faster cell segregation leading to the formation of more extensive patterns. The growth of the characteristic scale of patterns generally follows an algebraic scaling law with exponent values up to 0.74 in the presence of collective motion, compared to significantly smaller exponents in case of diffusive motion.
- Published
- 2012
- Full Text
- View/download PDF
34. Detection of Dobrava-Belgrade hantavirus using recombinant-nucleocapsid-based enzyme-linked immunosorbent assay and SYBR Green-based real-time reverse transcriptase-polymerase chain reaction.
- Author
-
Németh V, Madai M, Maráczi A, Bérczi B, Horváth G, Oldal M, Kisfali P, Bányai K, and Jakab F
- Subjects
- Animals, Croatia epidemiology, Female, Fluorescent Dyes, Orthohantavirus genetics, Hungary epidemiology, Male, Phylogeny, Rodent Diseases epidemiology, Rodent Diseases virology, Enzyme-Linked Immunosorbent Assay methods, Orthohantavirus isolation & purification, Murinae virology, Reverse Transcriptase Polymerase Chain Reaction methods
- Abstract
Dobrava (DOBV) hantaviruses belong to the genus Hantavirus, family Bunyaviridae, and are carried by yellow-necked and striped field mice. The goal of this study was to detect DOBV using serological and genetic methods in Apodemus rodents in Hungary and in northern Croatia. During the study period, a total of 125 Apodemus sp. (67 A. agrarius, 58 A. flavicollis) were tested for the presence of hantaviruses, and 21 rodents (17%) were positive by rRT-PCR and/or ELISA. We conclude that the prevalence of DOBV is much higher than previously anticipated. The simultaneous use of molecular and serological techniques provides a highly reliable way to detect hantavirus infections.
- Published
- 2011
- Full Text
- View/download PDF
35. Dobrava-Belgrade hantavirus infection mimics acute appendicitis.
- Author
-
Jakab F, Sebok J, Szántó Z, Hang D, Imre M, Németh V, Madai M, Oldal M, Kovács T, and Wittmann I
- Subjects
- Adult, Appendicitis diagnosis, Diagnosis, Differential, Orthohantavirus isolation & purification, Hemorrhagic Fever with Renal Syndrome immunology, Humans, Hungary, Immunoglobulin G blood, Immunoglobulin M blood, Male, Reverse Transcriptase Polymerase Chain Reaction, Antibodies, Viral blood, Orthohantavirus immunology, Hemorrhagic Fever with Renal Syndrome diagnosis
- Abstract
Dobrava-Belgrade hantavirus infection mimicked acute appendicitis in a patient suffering from hemorrhagic fever with renal syndrome in Hungary. The 27-year-old man was admitted to the local hospital with severe abdominal pain localized mainly at the right lower quadrant of the abdomen and with fever, nausea, vomiting and bloody diarrhea. Based on these findings supported by computerized tomography acute perforated appendicitis was suspected and an explorative laparatomy was performed, which did not confirm the diagnosis. Next day he developed acute oliguric renal failure raising the possibility of hantavirus infection. Specific serum IgG and IgM antibodies against hantavirus were identified, and by molecular methods the presence of Dobrava-Belgrade virus was proven. This report describes a rare clinical manifestation of hemorrhagic fever with renal syndrome (HFRS), and shows that HFRS might be difficult to diagnose especially when symptoms mimick those of an acute abdominal inflammation., (Copyright © 2010 Elsevier B.V. All rights reserved.)
- Published
- 2011
- Full Text
- View/download PDF
36. Viral epidemics in a cell culture: novel high resolution data and their interpretation by a percolation theory based model.
- Author
-
Gönci B, Németh V, Balogh E, Szabó B, Dénes Á, Környei Z, and Vicsek T
- Subjects
- Animals, Astrocytes cytology, Astrocytes virology, Computer Simulation, Culture Media metabolism, Epidemics, Fractals, Green Fluorescent Proteins metabolism, Herpesvirus 1, Suid genetics, Immunohistochemistry methods, Kinetics, Mice, Models, Statistical, Normal Distribution, Software, Cells, Cultured virology, Virus Diseases epidemiology
- Abstract
Because of its relevance to everyday life, the spreading of viral infections has been of central interest in a variety of scientific communities involved in fighting, preventing and theoretically interpreting epidemic processes. Recent large scale observations have resulted in major discoveries concerning the overall features of the spreading process in systems with highly mobile susceptible units, but virtually no data are available about observations of infection spreading for a very large number of immobile units. Here we present the first detailed quantitative documentation of percolation-type viral epidemics in a highly reproducible in vitro system consisting of tens of thousands of virtually motionless cells. We use a confluent astroglial monolayer in a Petri dish and induce productive infection in a limited number of cells with a genetically modified herpesvirus strain. This approach allows extreme high resolution tracking of the spatio-temporal development of the epidemic. We show that a simple model is capable of reproducing the basic features of our observations, i.e., the observed behaviour is likely to be applicable to many different kinds of systems. Statistical physics inspired approaches to our data, such as fractal dimension of the infected clusters as well as their size distribution, seem to fit into a percolation theory based interpretation. We suggest that our observations may be used to model epidemics in more complex systems, which are difficult to study in isolation.
- Published
- 2010
- Full Text
- View/download PDF
37. Epidemiological and clinical characterization of norovirus infections among hospitalized children in Baranya County, Hungary.
- Author
-
Jakab F, Németh V, Oldal M, Varga L, Nyul Z, Oldal M, Mitchell DK, Matson DO, Oldal M, Szucs G, and Oldal M
- Subjects
- Adolescent, Caliciviridae Infections virology, Child, Child, Preschool, Feces virology, Female, Gastroenteritis virology, Humans, Hungary epidemiology, Infant, Length of Stay, Male, Norovirus isolation & purification, Caliciviridae Infections epidemiology, Caliciviridae Infections physiopathology, Gastroenteritis epidemiology, Gastroenteritis physiopathology, Hospitalization statistics & numerical data, Norovirus pathogenicity
- Published
- 2010
- Full Text
- View/download PDF
38. Crystallization and preliminary X-ray studies of dUTPase from Mason-Pfizer monkey retrovirus.
- Author
-
Barabás O, Németh V, and Vértessy BG
- Subjects
- Crystallization, Models, Molecular, Nucleocapsid Proteins isolation & purification, Protein Conformation, Pyrophosphatases genetics, Pyrophosphatases isolation & purification, Pyrophosphatases metabolism, Viral Proteins chemistry, Viral Proteins genetics, Viral Proteins isolation & purification, Viral Proteins metabolism, X-Ray Diffraction, Mason-Pfizer monkey virus enzymology, Pyrophosphatases chemistry
- Abstract
Deoxyuridine 5'-triphosphate nucleotidohydrolase from Mason-Pfizer monkey retrovirus (M-PMV dUTPase) is a betaretroviral member of the dUTPase enzyme family. In the mature M-PMV virion, this enzyme is present as the C-terminal domain of the fusion protein nucleocapsid-dUTPase. The homotrimeric organization characteristic of dUTPases is retained in this bifunctional fusion protein. The fusion protein supposedly plays a role in adequate localization of dUTPase activity in the vicinity of nucleic acids during reverse transcription and integration. Here, the nucleocapsid-free dUTPase (48 426 Da) was cocrystallized with a dUTP substrate analogue using the hanging-drop vapour-diffusion method. The obtained crystals belong to the primitive hexagonal space group P6(3), with unit-cell parameters a = 60.6, b = 60.6, c = 63.6 angstroms, alpha = 90, beta = 90, gamma = 120 degrees. Native and PtCl4-derivative data sets were collected using synchrotron radiation to 1.75 and 2.3 angstroms, respectively. Phasing was successfully performed by isomorphous replacement combined with anomalous scattering.
- Published
- 2006
- Full Text
- View/download PDF
39. Effect of the Ca2+ chelators EDTA and EGTA on sinoatrial-node activity and heart irritability.
- Author
-
Solti F, Juhász-Nagy S, Kecskeméti V, Czakó B, Németh V, and Kékesi V
- Subjects
- Animals, Arrhythmias, Cardiac chemically induced, Dogs, Electrocardiography, Heart physiology, Heart physiopathology, Sinoatrial Node drug effects, Sinoatrial Node physiopathology, Arrhythmias, Cardiac physiopathology, Edetic Acid pharmacology, Egtazic Acid pharmacology, Ethylene Glycols pharmacology, Heart drug effects, Sinoatrial Node physiology
- Abstract
The effect of the Ca-chelators EDTA and EGTA on sinoatrial activity and heart irritability was studied in dog experiments by perfusing the artery supplying the sinoatrial node. Beside the usual ECG recordings left and right atrial and left and right ventricular epicardial electrograms, His-bundle electrogram and the early activity of the sinoatrial node were recorded. In addition action potentials were recorded from the left auricle and right ventricle of the dog hearts. Local application around the sinoatrial and atrio-ventricular nodes of EDTA and EGTA caused sinus bradycardia and later sinus arrest within 1 min after introduction of the drugs. For substitution of the sinus rhythm junctional (seldom lower atrial) escape rhythm developed. One to two minutes later it was followed by atrial premature beats and even later atrial flutter and fibrillation could be recorded. In one third of the cases atrial fibrillation was followed by secondary ventricular fibrillation. Atrio-ventricular impulse conduction was prolonged in the av node by EDTA and EGTA. Atrial action potentials and the slow (Ca dependent) ventricular action potentials were depressed by EDTA and EGTA.
- Published
- 1982
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.