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1.
PLoS One ; 17(10): e0274976, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36197884

RESUMO

This study investigates PhD candidates' (N = 391) perceptions about their research environment at a Dutch university in terms of the research climate, (un)ethical supervisory practices, and questionable research practices. We assessed whether their perceptions are related to career considerations. We gathered quantitative self-report estimations of the perceptions of PhD candidates using an online survey tool and then conducted descriptive and within-subject correlation analysis of the results. While most PhD candidates experience fair evaluation processes, openness, integrity, trust, and freedom in their research climate, many report lack of time and support, insufficient supervision, and witness questionable research practices. Results based on Spearman correlations indicate that those who experience a less healthy research environment (including experiences with unethical supervision, questionable practices, and barriers to responsible research), more often consider leaving academia and their current PhD position.


Assuntos
Inquéritos e Questionários , Humanos , Autorrelato
2.
J Oral Pathol Med ; 44(9): 722-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25495524

RESUMO

Oral human papillomavirus (HPV) carriage rates were investigated in relation to genital HPV carriage in women with HPV-associated cervical lesions and male partner of such women, including several couples, in comparison with healthy individuals. Buccal and lingual mucosa of 60 males and 149 females with healthy oral mucosa and without known genital lesion, genital and oral mucosa of further 40 females with cervical high-grade squamous intraepithelial lesion (HSIL) and 34 male sexual partners of women with HSIL (including 20 couples) were sampled. HPV DNA was detected using MY/GP PCR. Genotype was determined by sequencing or restriction fragment length polymorphism. Virus copy numbers were determined by real-time PCR. Overall, oral HPV carriage rate was 5.7% (12/209) in healthy individuals; average copy number was 5.8 × 10(2) copies/1 µg DNA; male and female rates were comparable. Oral carriage in women with HSIL was significantly higher, 20.0% (8/40, P = 0.003); males with partners with HSIL showed a carriage rate of 17.6% (6/34), copy numbers were similar to the healthy controls. In contrast, genital carriage rate (52.9%, 18/34 vs. 82.5%, 33/40; P = 0.006) and average copy number were lower in males (5.0 × 10(5) vs. 7.8 × 10(5) copies/1 µg DNA; P = 0.01). Oral copy numbers in these groups and in healthy individuals were comparable. High-risk genotypes were dominant; couples usually had the same genotype in the genital sample. In conclusion, genital HPV carriage is a risk factor of oral carriage for the individual or for the sexual partner, but alone is not sufficient to produce an oral HPV infection in most cases.


Assuntos
Carcinoma de Células Escamosas/virologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/patologia , Criança , DNA Viral , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/patologia , Mucosa Bucal/virologia , Gradação de Tumores , Papillomaviridae/genética , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Polimorfismo Genético , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Parceiros Sexuais , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/patologia , Adulto Jovem , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/patologia
3.
Pathol Oncol Res ; 20(4): 923-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24710824

RESUMO

Occurrence of genetic and epigenetic alterations affecting p14ARF and p16INK4A were investigated in tumour samples of 37 oral (OSCC) and 28 laryngeal squamous cell cancer (LSCC) patients, and compared to exfoliated buccal epithelial cells of 68 healthy controls. Presence of deletions and mutations/polymorphisms affecting exons were examined using sequencing. Methylation status of promoters was assessed by methylation-specific PCR. Chi-square and Fisher's exact tests were used to compare frequency of events. Exon deletions were found in four controls, one OSCC and 22 LSCC patients; the latter significantly differed from controls (p < 0.001). Only two mutations (T24610A and C24702A) were in p16 exon 1 of two OSCC patients. Polymorphisms G28575A (Ala140Thr), G31292C (C540G) and G28608A were found in both patient groups. The p14 promoter was unmethylated in 86.7 % of OSCC and in 85.7 % of LSCC patients; for the p16 promoter these rates were 69.0 % and 76.2 % for OSCC and LSCC patients, respectively. Combining the two patient groups, unmethylated promoter was significantly less frequent in case of both p14 and p16 (p = 0.043 and p = 0.001, respectively) compared to the control group. In summary, exon deletion may be important in LSCC, while promoter methylation was relatively frequent in both patient groups.


Assuntos
Carcinoma de Células Escamosas/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Epigênese Genética/genética , Deleção de Genes , Neoplasias Laríngeas/genética , Neoplasias Bucais/genética , Proteína Supressora de Tumor p14ARF/genética , Adulto , Idoso , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/mortalidade , Estudos de Casos e Controles , Metilação de DNA , Feminino , Seguimentos , Inativação Gênica , Humanos , Hungria/epidemiologia , Neoplasias Laríngeas/epidemiologia , Neoplasias Laríngeas/mortalidade , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/epidemiologia , Neoplasias Bucais/mortalidade , Mutação/genética , Prognóstico , Regiões Promotoras Genéticas/genética , Taxa de Sobrevida
4.
Med Microbiol Immunol ; 202(5): 353-63, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23649705

RESUMO

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.


Assuntos
Genoma Viral , Papillomavirus Humano 11/genética , Papillomavirus Humano 11/patogenicidade , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Polimorfismo Genético , Infecções Respiratórias/patologia , Infecções Respiratórias/virologia , Criança , Pré-Escolar , Feminino , Papillomavirus Humano 11/isolamento & purificação , Humanos , Lactente , Mutagênese Sítio-Dirigida , Mutação , Análise de Sequência de DNA , Virulência
5.
Acta Microbiol Immunol Hung ; 58(4): 319-37, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22207290

RESUMO

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.


Assuntos
Mucosa/virologia , Torque teno virus/classificação , Feminino , Variação Genética , Genótipo , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Leucoplasia Oral/virologia , Líquen Plano/virologia , Neoplasias de Células Escamosas/virologia , Filogenia , Torque teno virus/genética , Neoplasias do Colo do Útero/virologia
6.
Antiviral Res ; 92(2): 356-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21945249

RESUMO

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.


Assuntos
Antivirais/administração & dosagem , Citosina/análogos & derivados , Genoma Viral , Papillomavirus Humano 11/genética , Organofosfonatos/administração & dosagem , Infecções por Papillomavirus/tratamento farmacológico , Infecções por Papillomavirus/virologia , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/virologia , Cidofovir , Citosina/administração & dosagem , Metilação de DNA , DNA Viral/química , DNA Viral/genética , Epigênese Genética , Papillomavirus Humano 11/isolamento & purificação , Humanos , Dados de Sequência Molecular , Mutação , Polimorfismo Conformacional de Fita Simples , Análise de Sequência de DNA , Falha de Tratamento
7.
J Lipid Res ; 51(2): 286-96, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19654424

RESUMO

The importance of membrane rafts in HIV-1 infection is still in the focus of interest. Here, we report that new monoclonal anticholesterol IgG antibodies (ACHAs), recognizing clustered membrane cholesterol (e.g., in lipid rafts), rearrange the lateral molecular organization of HIV-1 receptors and coreceptors in the plasma membrane of HIV-1 permissive human T-cells and macrophages. This remodeling is accompanied with a substantial inhibition of their infection and HIV-1 production in vitro. ACHAs promote the association of CXCR4 with both CD4 and lipid rafts, consistent with the decreased lateral mobility of CXCR4, while Fab fragments of ACHAs do not show these effects. ACHAs do not directly mask the extracellular domains of either CD4 or CXCR4 nor do they affect CXCR4 internalization. No significant inhibition of HIV production is seen when the virus is preincubated with the antibodies prior to infection. Thus, we propose that the observed inhibition is mainly due to the membrane remodeling induced by cholesterol-specific antibodies on the target cells. This, in turn, may prevent the proper spatio-temporal juxtaposition of HIV-1 glycoproteins with CD4 and chemokine receptors, thus negatively interfering with virus attachment/entry.


Assuntos
Anticorpos Monoclonais/farmacologia , Especificidade de Anticorpos/imunologia , Colesterol/imunologia , Colesterol/metabolismo , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Replicação Viral/efeitos dos fármacos , Animais , Anticorpos Monoclonais/imunologia , Antígenos CD4/metabolismo , Linhagem Celular , Humanos , Imunoglobulina G/imunologia , Imunoglobulina G/farmacologia , Macrófagos/imunologia , Macrófagos/metabolismo , Microdomínios da Membrana/imunologia , Microdomínios da Membrana/metabolismo , Camundongos , Movimento , Receptores CXCR4/metabolismo , Ressonância de Plasmônio de Superfície , Linfócitos T/imunologia , Linfócitos T/metabolismo , Ligação Viral , Internalização do Vírus
8.
Eur J Oral Sci ; 117(5): 536-40, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19758249

RESUMO

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.


Assuntos
Carcinoma de Células Escamosas/virologia , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/isolamento & purificação , Neoplasias Bucais/virologia , Lesões Pré-Cancerosas/virologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antígenos Virais/análise , Capsídeo/virologia , Estudos de Casos e Controles , Feminino , Herpesvirus Humano 4/imunologia , Humanos , Hungria , Leucoplasia Oral/virologia , Líquen Plano Bucal/virologia , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/virologia , Proteínas Oncogênicas Virais/análise , Fatores de Risco , Carga Viral , Proteínas da Matriz Viral/análise , Adulto Jovem
9.
J Med Virol ; 81(11): 1975-81, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19774682

RESUMO

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.


Assuntos
Neoplasias Bucais/virologia , Neoplasias de Células Escamosas/virologia , Infecções por Papillomavirus/complicações , Neoplasias do Colo do Útero/virologia , Viroses/epidemiologia , Vírus/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
10.
Orv Hetil ; 150(19): 903-7, 2009 May 10.
Artigo em Húngaro | MEDLINE | ID: mdl-19403434

RESUMO

The purpose of this study was to examine the effect of Guardian Angel powder (GA) on the blood alcohol level. According to the experimental protocol, two sets of measurement were performed: modeling the eating and drinking habit of a typical family or social meeting, alcohol containing drinks corresponding to 70 g of pure alcohol and copious amount of food were consumed first without GA powder, then with GA powder. In the latter case GA powder was dissolved in water and one dose was taken before eating, the other one was consumed during eating. Blood samples were hourly collected from the volunteers in both sets for four hours. The measurement of blood alcohol level was performed by gas chromatography-mass spectrometry method proceeding to Solid Phase Micro Extraction (SPME). Our results show that the blood alcohol level decreased significantly when two doses of GA powder were consumed. After two hours of taking GA powder, the blood alcohol level was significantly lower in each volunteers compared to their own blood alcohol level measured in the absence of GA powder. This result shows that the individual variation of the alcohol metabolism does not influence significantly the effect of GA powder. Further studies are needed to investigate the detailed mechanism of the action of GA powder to find out whether GA powder influences the absorption of alcohol or/and the metabolism of alcohol.


Assuntos
Consumo de Bebidas Alcoólicas/sangue , Bebidas Alcoólicas , Etanol/sangue , Administração Oral , Adulto , Idoso , Índice de Massa Corporal , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Pós , Valores de Referência , Fatores de Tempo
11.
Pharmacol Rep ; 61(2): 343-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19443949

RESUMO

In this short communication, it is shown that 4-thio-uridylate (s(4)UMP, designated as UD29) inhibits glyceraldehyde 3-phosphate dehydrogenase (GAPDH), suggesting that the enol-form of the thiolated nucleotide may interfere with the function of the essential -SH group in the active center of the enzyme. Since HIV entry requires thiol/disulfide exchange processes, this activity prompted us to study the anti-HIV activity of the nucleotide. Indeed, UD29 inhibited the replication of HIV-1(IIIB) in the MT-4 cell line and HIV-1(Ada-M) in peripheral blood mononuclear cells (PBMC). Furthermore, UD29 was not toxic in PBMCs in vitro or in mice when the compound was administered intravenously.


Assuntos
Fármacos Anti-HIV/farmacologia , Inibidores Enzimáticos/farmacologia , Gliceraldeído-3-Fosfato Desidrogenases/antagonistas & inibidores , HIV-1/efeitos dos fármacos , Compostos de Sulfidrila/metabolismo , Tionucleotídeos/farmacologia , Uridina Monofosfato/análogos & derivados , Replicação Viral/efeitos dos fármacos , Animais , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Uridina Monofosfato/farmacologia
12.
Orv Hetil ; 147(33): 1539-44, 2006 Aug 20.
Artigo em Húngaro | MEDLINE | ID: mdl-17037676

RESUMO

INTRODUCTION: Epstein-Barr virus is a ubiquitous human herpes virus in the Hungarian population. The virus is associated with an increasing number of lymphoid malignancies, such as Hodgkin and non-Hodgkin lymphomas. The ability of the virus to establish life-long persistent infection and induce growth transformation is related to the viral proteins that are variously expressed in both normal and malignant cells. Although the presence of ZEBRA protein induces lytic cycle, some lymphoma cases show this protein expression. AIM: In our present study we investigated the frequency of expression of ZEBRA protein in Hungarian patients with Hodgkin lymphoma associated with Epstein-Barr virus infection. The authors wanted to clarify whether this expression is specific to latency type II or occurs in some non-Hodgkin lymphoma cases with latency type III as well. Does the expression of ZEBRA protein have any effect on therapeutic response and survival rate of the patients? METHOD: 109 HL and 59 NHL were studied for the presence of the virus in the tumor and for expression of the latency proteins and ZEBRA by immunohistochemistry. RESULTS: 25 samples were evaluated successfully for ZEBRA of the 47 LMP1 positive HL samples. We detected the weak expression of ZEBRA protein in 13 of the 25 LMP1 positive Hodgkin lymphoma cases and in 6 of the 18 LMP1 positive non-Hodgkin lymphoma samples. The authors could not find correlation between the expression of ZEBRA protein and the type of latency. During the followed 120 months the total survival of patients with ZEBRA positivity proved to be significantly shorter as compared to that of ZEBRA negative cases. The authors could not find significant difference in the uneventful survival of these two groups. CONCLUSION: In the examined group of patients the ZEBRA positivity associated with a poor prognosis of the disease. Besides this relatively small number of cases, additional extensive studies are needed to conclude our observation. Elucidation of the switching mechanisms by which Epstein-Barr virus induces lytic cycle may provide an efficacious therapeutic approach to the EBV-related malignancies.


Assuntos
Proteínas de Ligação a DNA/análise , Infecções por Vírus Epstein-Barr/metabolismo , Herpesvirus Humano 4/metabolismo , Doença de Hodgkin/metabolismo , Doença de Hodgkin/virologia , Transativadores/análise , Proteínas Virais/análise , Adulto , Idoso , Infecções por Vírus Epstein-Barr/complicações , Antígenos Nucleares do Vírus Epstein-Barr/análise , Feminino , Regulação Neoplásica da Expressão Gênica , Regulação Viral da Expressão Gênica , Doença de Hodgkin/terapia , Humanos , Hungria , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida , Resultado do Tratamento , Proteínas da Matriz Viral/análise
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