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1.
Diagn Pathol ; 18(1): 124, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37964347

RESUMO

AIMS: The association of human herpesvirus 6 (HHV-6) species with pancreatic cancer is controversially discussed. The aim of this study was to further investigate the postulated association and to identify the basis of HHV-6 DNA positivity reported for pancreatic cancer tissue. METHODS: All samples of patients with pancreatic cancer (cancer and surrounding tissue) were analyzed for presence of HHV-6 DNA by PCR and then selected cases by immunohistochemistry. RESULTS: Sixty eight per cent (68% = 52/77) of all patients were HHV-6 DNA positive in any of the samples, 49% (38/77) were positive in tumor tissue. Specimens of just one patient were HHV-6A DNA positive, all other patients were positive for HHV-6B. Immunohistochemical analysis of HHV-6 DNA positive samples did not reveal any specific HHV-6B protein positive tumor cell. In contrast, supposed immune cells presented intra- and peritumorally expressed HHV-6B-protein. The cause of presence of these cells in the tumor stroma is unknown, as of yet. CONCLUSIONS: HHV-6 DNA-positivity of pancreatic cancer tissue described by us and others is probably not due to the infection of pancreatic cells by HHV-6, but rather due to the migration of HHV-6 positive immune cells into the pancreas. Based on our data, we suppose that there is no direct evidence for HHV-6 as a causative agent of pancreatic cancer, but further in-depth studies (including investigation of immune status of patients) are necessary to make definitive conclusions.


Assuntos
Adenocarcinoma , Carcinoma Ductal Pancreático , Herpesvirus Humano 6 , Neoplasias Pancreáticas , Infecções por Roseolovirus , Humanos , Herpesvirus Humano 6/genética , Infecções por Roseolovirus/diagnóstico , Infecções por Roseolovirus/genética , DNA Viral/genética , Neoplasias Pancreáticas
2.
Vaccine ; 39(40): 5918-5927, 2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34462165

RESUMO

Juvenile Idiopathic Arthritis (JIA) patients living in areas with high prevalence of tick-borne-encephalitis-virus-(TBEV)-infection are recommended for administration of inactivated TBE-vaccination. However, there are serious concerns regarding protective vaccine-induced immune responses against TBEV in immunocompromised patients. The present study aimed to analyze the humoral and cellular immune response to TBE-vaccination in previously TBE-vaccinated JIA patients compared to healthy controls (HC) including investigation of IgG-anti-TBEV avidity, neutralization capacity, cellular reactivity by IFNgamma-ELISPOT and cytokine secretion assays. Similar IgG-anti-TBEV antibody concentrations, neutralization titers and cellular reactivity were found between JIA and HC. The number and the early timing of booster vaccinations after primary vaccination had the most prominent effect on neutralizing antibodies in JIA and on IgG-anti-TBEV concentrations in both JIA and HC. Administration of booster vaccinations made it more likely for JIA patients to have IgG-anti-TBEV concentrations ≥165 VIEU/ml and avidities >60%. TNF-alpha inhibitors had a positive and MTX administration a negative effect on humoral immune responses. In conclusion, irrespective of having JIA or not, vaccinated children showed similar humoral and cellular immunity against TBEV several years after primary TBE-vaccination. However, in JIA, booster vaccinations mounted a significantly higher humoral immune response than in JIA without boosters. Our results highlight the need for timely administration of boosters particularly in JIA. Although immunosuppressive treatment at vaccinations in diagnosed JIA had a negative effect mainly on TBEV-specific cellular immunity, most JIA patients mounted a favorable humoral immune response which was maintained over time. Thus, successful TBE-vaccination seems highly feasible in JIA patients with immunosuppressive regimens.


Assuntos
Artrite Juvenil , Encefalite Transmitida por Carrapatos , Carrapatos , Vacinas Virais , Animais , Anticorpos Antivirais , Criança , Encefalite Transmitida por Carrapatos/prevenção & controle , Humanos , Imunidade Celular , Vacinação
3.
Eur J Clin Microbiol Infect Dis ; 30(12): 1561-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21573818

RESUMO

The purpose of this study was to delineate the spectrum of neurological diseases attributed to Epstein-Barr virus (EBV) activity. The approach was a retrospective study on patients with EBV activity proven by a positive EBV antibody-specific index (AI) and/or cerebrospinal fluid (CSF) PCR. One hundred six children and adults (AI positive = 77, AI + PCR positive = 3, PCR positive = 26) were identified, most with reactivated infections. Twenty-eight showed typical EBV-related diseases (encephalitis, neuritis, meningitis), 19 further infections (HSV encephalitis, neuroborreliosis, HIV infection, bacterial meningitis), nine immune-mediated disorders (multiple sclerosis, optic neuritis), and 50 further diseases not typical for EBV. The highest AI values occurred in patients with encephalitis. No relationship between disease category or AI values and viral loads was found. Additional reanalysis of 1,500 consecutive CSF EBV PCR studies revealed the highest positive rates among patients with further infections (n = 18/227, 7.9%) but lower rates among patients with typical EBV-related disorders (5/395; 1.3%), immune-mediated disorders (n = 2/174; 1.1%) and other conditions (n = 4/704; 0.6%). Intrathecal EBV activity is not restricted to typical EBV-related disorders, unexpectedly frequent in further CNS infections and also present in non-inflammatory conditions. Prospective studies should assess the pathogenic role of EBV in these different diseases.


Assuntos
Encefalite Viral/epidemiologia , Encefalite Viral/virologia , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/patogenicidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Líquido Cefalorraquidiano/virologia , Criança , Pré-Escolar , DNA Viral/líquido cefalorraquidiano , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Carga Viral , Adulto Jovem
4.
J Clin Virol ; 50(2): 175-6, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21084220

RESUMO

Hepatitis E virus (HEV) is well-known to cause endemic outbreaks of hepatitis in tropical countries, mostly caused by HEV genotypes 1 or 2 and transmitted from humans to humans via the fecal-oral route. In contrast, HEV genotypes 3 or 4 are commonly encountered as sporadic cases in a non-endemic setting; these autochthonous cases are transmitted from animals to humans and commonly affect elderly male subjects. We report a five-month-old caucasian girl presenting with diarrhea, emesis, and elevated ALT. Surprisingly, acute infection with Hepatitis E virus (HEV) genotype 3 was laboratory-confirmed by reverse transcriptase polymerase chain reaction (RT-PCR) and sequencing. Thirteen months later, RT-PCR for HEV from stool tested negative whereas anti-HEV IgG in serum tested positive. Neither HEV RNA nor anti-HEV antibodies could be detected in stool or serum of the parents. To our knowledge, this is the first pediatric case of a HEV infection in Germany. Thus, HEV should be included into the differential diagnosis of pediatric infectious liver and bowel disease.


Assuntos
Vírus da Hepatite E/isolamento & purificação , Hepatite E/diagnóstico , RNA Viral/sangue , Sequência de Bases , Fezes/virologia , Feminino , Genótipo , Alemanha , Anticorpos Anti-Hepatite/sangue , Hepatite E/virologia , Vírus da Hepatite E/imunologia , Humanos , Imunoglobulina G/sangue , Lactente , RNA Viral/análise , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Infection ; 38(5): 401-5, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20589523

RESUMO

BACKGROUND: Respiratory infection and failure is a commonly encountered problem in intensive care unit (ICU) patients. However, despite the accumulating body of evidence to suggest that herpes simplex virus type 1 (HSV-1) is associated with pneumonia, the exact role played by this virus in this process is still not fully understood. Therefore, to identify patients at risk, we have conducted a case-control study to characterize patients with HSV-1-positive pneumonia. PATIENTS AND METHODS: Between 2007 and 2009, all patients with suspected viral pneumonia were tested for the presence of herpes viruses using a PCR assay approach with respiratory specimens. To identify possible associations, risk factors, and impact of HSV, HSV-1-positive ICU patients (n = 51) were compared to age-, gender-, and department- and season-matched HSV-negative patients (n = 52). RESULTS: HSV-positive patients differed significantly from the HSV-negative ones only in terms of time of mechanical ventilation (13 vs. 6 days, respectively; p = 0.002). Subgroup analysis in the patients aged >60 years and in those without bacterial detection revealed a similar trend (p = 0.01 and p = 0.004, respectively). Mortality did not differ between the groups or between the HSV-1-positive patients treated with aciclovir and those who were not. A viral load >10E+05 geq/ml was associated with mechanical ventilation (20/21 vs. 17/29; p = 0.004), acute respiratory distress syndrome (ARDS; 19/21 vs. 18/29; p = 0.005), sepsis (18/21 vs. 14/29; p = 0.008), detection of a bacterial pathogen in the same specimen (10/21 vs. 4/29; p = 0.01) and longer ICU stay (25 vs. 30 days; p = 0.04). CONCLUSION: Despite several associations with high viral load, the clinical outcome of HSV-1-positive ICU patients did not differ significantly from the clinical outcome of HSV-negative patients. This finding indicates that HSV-1 viral loads in respiratory specimens are a symptom of a clinically poor condition rather than a cause of it. Longitudinal and therapy studies are therefore needed to distinguish between HSV-1 as a causative pathogen and HSV-1 as a bystander of pneumonia/ARDS.


Assuntos
Pneumonia Viral/virologia , Sistema Respiratório/virologia , Simplexvirus/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/mortalidade , Respiração Artificial/efeitos adversos , Simplexvirus/genética , Simplexvirus/fisiologia , Carga Viral
6.
Pneumologie ; 64(2): 115-23, 2010 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-20143283

RESUMO

In industrialized countries respiratory tract infections are one of the most common reasons for medical consultations. It is assumed that almost one third of these infections include the lower respiratory tract (LRTI), e. g. acute bronchitis, acute exacerbation of chronic obstructive pulmonary disease (COPD), community- or hospital-acquired pneumonia and influenza. Due to a lack of sufficient and valid investigations to prove the presence of respiratory viruses their impact in the pathogenesis of lower respiratory tract infection has probably been underestimated for a long time. Therefore, there might have been many cases of unnecessary antibiotic treatment, especially in cases of acute bronchitis or acute exacerbations of COPD, because of an assumed bacteriological cause. With the introduction of more sensitive investigational procedures, such as polymerase chain reaction, it is possible to sufficiently prove respiratory viruses and therefore illuminate their role in the pathogenesis of lower respiratory tract infections of the adult. We have reviewed the current literature on the impact of viruses in lower respiratory tract infections to elucidate the role of viruses in the pathogenesis of lower respiratory tract infections. The preceding parts of this series provided an introduction to the frequently found viruses, pathogenesis, and diagnostic procedures (part I) as well as common viral infections of the lower respiratory tract (part II). The present 3 (rd) part deals with therapy for and prevention of viral LRTI.


Assuntos
Antivirais/uso terapêutico , Bronquite/tratamento farmacológico , Broncodilatadores/uso terapêutico , Glucocorticoides/uso terapêutico , Influenza Humana/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Viroses/tratamento farmacológico , Adulto , Antivirais/efeitos adversos , Bronquite/diagnóstico , Bronquite/prevenção & controle , Broncodilatadores/efeitos adversos , Terapia Combinada , Farmacorresistência Viral , Glucocorticoides/efeitos adversos , Humanos , Influenza Humana/diagnóstico , Influenza Humana/prevenção & controle , Pneumonia Viral/diagnóstico , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Viroses/diagnóstico , Viroses/prevenção & controle , Viroses/transmissão
7.
Pneumologie ; 64(1): 18-27, 2010 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-20091441

RESUMO

In industrialized countries respiratory tract infections are one of the most common reasons for medical consultations. It is assumed that almost one third of these infections affect the lower respiratory tract (LRTI), e. g. acute bronchitis, acute exacerbation of chronic obstructive pulmonary disease (COPD), community- or hospital-acquired pneumonia and influenza. Due to a lack of sufficient and valid investigations on the epidemiology of respiratory viruses, their impact on the pathogenesis of LRTI has probably been underestimated for a long time. Therefore, there might have been many cases of needless antibiotic treatment, particularly in cases of acute bronchitis or acute exacerbations of COPD, because of an assumed bacteriological aetiology. Following the introduction of diagnostic procedures with increased sensitivity, such as polymerase chain reaction, it is possible to reliably detect respiratory viruses and to illuminate their role in the pathogenesis of LRTI of the adult. We have reviewed the current literature to elucidate the role of viruses in the pathogenesis of LRTI. The first part of this series described frequent viral pathogens, pathogenesis of viral LRTI, and diagnostic procedures. In this 2 (nd) part the aetiological role of viruses in the most frequent forms of LRTI will be highlighted, and the third and last part will provide an overview of therapeutic and preventive options.


Assuntos
Bronquite/virologia , Doença Pulmonar Obstrutiva Crônica/virologia , Infecções Respiratórias/virologia , Viroses/virologia , Diagnóstico Diferencial , Humanos
8.
Pneumologie ; 63(12): 709-17, 2009 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-19890777

RESUMO

In industrialised countries respiratory tract infections are one of the most common reasons for medical consultations. It is assumed that almost one third of these infections include the lower respiratory tract (LRTI), e. g. acute bronchitis, acute exacerbation of chronic obstructive pulmonary disease (COPD), community- or hospital-acquired pneumonia and influenza. Due to a lack of sufficient and valid investigations on the epidemiology of respiratory viruses, their impact on the pathogenesis of LRTI has probably been underestimated for a long time. Therefore, there might have been many cases of needless antibiotic treatment, particularly in cases of acute bronchitis or acute exacerbations of COPD, because of an assumed bacteriological aetiology. Following the introduction of diagnostic procedures with increased sensitivity, such as polymerase chain reaction, it is possible to reliably detect respiratory viruses and to illuminate their role in the pathogenesis of LRTI of the adult. We have reviewed the current literature to elucidate the role of viruses in the pathogenesis of LRTI. The first part of this series deals with the relevant pathogens, pathogenesis, and diagnostic procedures. In the subsequent 2 parts of this series a review will be given on the most common variants of viral LRTI (part II), and therapeutic and preventive options (part III).


Assuntos
Infecções Respiratórias/diagnóstico , Infecções Respiratórias/virologia , Viroses/diagnóstico , Viroses/virologia , Adulto , Diagnóstico Diferencial , Humanos
9.
Klin Padiatr ; 220(5): 296-301, 2008.
Artigo em Alemão | MEDLINE | ID: mdl-18716982

RESUMO

BACKGROUND: Apart from established pathogens of lower respiratory tract infections, such as respiratory syncytial virus (RSV), an increasing number of additional agents has been identified in recent years. In 2005 the human bocavirus (hBoV) has been isolated from respiratory tract samples and has been reported worldwide with frequencies ranging from 1.5 to 18.3% in respiratory samples from children with airway infections. PATIENTS: We investigated 173 specimens of a total number of 162 children who were inpatients with severe respiratory tract infections most of whom required oxygen therapy. METHOD: We analyzed respiratory tract samples (83% nasopharyngeal washes, 15% tracheal secretions, 2% bronchoalveolar lavages) for adenoviruses, influenza A und B viruses, parainfluenzaviruses types 1 to 3 and RSV using antigen-specific immunofluorescence assays. Additionally we tested human metapneumovirus (hMPV) and hBoV using a PCR assay. MAIN RESULTS: 35.8% specimens were negative in all assays, 54.3% were positive for RSV and 9.8% were positive for adeno-, influenza-, parainfluenzaviruses or hMPV. HBoV could be detected in 17 specimens (9.8%), defining HBoV to be the second most frequent pathogen. Nine of these patients showed a coinfection with RSV, one with parainfluenza virus. Viral loads did range from 2x10 (2) to 5.6x10 (10) genome equivalents/ml with higher viral loads being observed in the first days after disease onset. Most children were infected in the months between December and April. Half of the patients with isolated HBoV infection showed rhinopharyngitis, a third suffered from pulmonary obstruction and nearly every second required oxygen therapy. However, no HBoV-specific symptoms were found. CONCLUSION: HBoV is a common pathogen causing viral respiratory tract infection in infants and young children. Among the here reported patients HBoV was the second most frequent identified pathogen. X-ray studies frequently revealed peribronchial and pneumonic infiltrates with only moderately elevated laboratory inflammatory markers. So far, no HBoV-specific clinical symptoms are known. Additional questions for example related to the way of transmission and optimal treatment remain to be investigated in prospective studies.


Assuntos
Bocavirus , Bronquite/virologia , Infecções por Parvoviridae , Infecções Respiratórias , Corticosteroides/administração & dosagem , Corticosteroides/uso terapêutico , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Bocavirus/isolamento & purificação , Lavagem Broncoalveolar , Criança , Pré-Escolar , Claritromicina/administração & dosagem , Claritromicina/uso terapêutico , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Infecções por Parvoviridae/tratamento farmacológico , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/virologia , Radiografia Torácica , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções Respiratórias/diagnóstico por imagem , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/virologia , Resultado do Tratamento , Carga Viral
11.
J Clin Microbiol ; 39(11): 3902-5, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11682505

RESUMO

The Enzygnost anti-Epstein-Barr virus enzyme-linked immunosorbent assay (ELISA) system, which is based on a defined antigen mixture and on detection of antibodies of the immunoglobulin G (IgG), IgM, and IgA classes, was evaluated for its reliability in diagnosing Epstein-Barr virus infections in childhood. With samples from 66 children, the Epstein-Barr virus status and the infection phase were defined by indirect immunofluorescence and anticomplement fluorescence assays: 11 children were seronegative, 8 had a primary infection, 20 had a recent primary or past infection, and in 27 a reactivated Epstein-Barr virus infection was diagnosed. When applying the Enzygnost ELISAs, 15 serum samples (22.7%) were not interpretable due to indeterminate results in at least one of the assays used and were therefore excluded from further evaluation. The respective sensitivities and specificities for the diagnosis of seronegativity were 100 and 100%, those for the diagnosis of primary infection were 100 and 97%, those for the diagnosis of recent primary or past infection were 100 and 52%, and those for the diagnosis of reactivated infection were 10 and 100%. This poor performance of the Enzygnost system with reactivated infections is due to the prerequisite of an IgG antibody value of >650 IU/ml for the diagnosis of viral activity, which was fulfilled in only two of the children. Despite the high rate of indeterminate results, the Enzygnost system is useful in diagnosing acute and past Epstein-Barr virus infection in childhood. For serological diagnosis of viral activity in childhood, a supplementary assay is necessary.


Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Infecções por Vírus Epstein-Barr/diagnóstico , Herpesvirus Humano 4/imunologia , Imunoglobulinas/sangue , Especificidade de Anticorpos , Criança , Pré-Escolar , Infecções por Vírus Epstein-Barr/virologia , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Lactente , Sensibilidade e Especificidade , Ativação Viral
12.
Gene ; 275(1): 157-62, 2001 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-11574164

RESUMO

A human homologue of the murine zinc finger protein zfr is transcriptionally induced in the Epstein-Barr virus-positive Burkitt lymphoma cell line Raji upon treatment with the granulocyte/macrophage lineage ganglioside IV(3)NeuAc-nLcOse(4)Cer. The gene was cloned by a rapid amplification of cDNA ends approach based on a cDNA clone. The resulting hzfr sequence is 3393 base pairs in length coding for a protein of 1057 amino acids. Sequence alignments between hzfr and zfr reveal an identity of 92% on the nucleotide level and an identity of 96.4% on the amino acid level, respectively. Based on Southern blot data hzfr can be addressed as a single copy gene. Tissue-specific expression was determined by semi-quantitative PCR of normalized cDNA populations from various human tissues with glyceraldehyde-3-phosphate dehydrogenase as an internal control. Highest levels of transcripts were found in brain. hzfr transcripts could not be detected in skeletal muscle.


Assuntos
Proteínas de Ligação a RNA/genética , Sequência de Aminoácidos , Animais , Southern Blotting , Clonagem Molecular , DNA/genética , DNA Complementar/química , DNA Complementar/genética , Feminino , Gangliosídeos/farmacologia , Dosagem de Genes , Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Dados de Sequência Molecular , RNA/genética , RNA/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Distribuição Tecidual , Células Tumorais Cultivadas
13.
J Clin Microbiol ; 38(11): 4006-9, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11060060

RESUMO

Detection of human cytomegalovirus (CMV) DNA in clinical specimens is considered a cornerstone in the diagnosis of CMV disease. The aim of this study was to evaluate a newly designed LightCycler-based quantitative CMV PCR. Specimens of human origin (n = 200) were tested using the LightCycler PCR, the quantitative COBAS AMPLICOR CMV MONITOR (CACM) assay, and a qualitative in-house PCR assay for the presence of CMV DNA. Samples that were reactive in at least two of the three assays were considered CMV DNA positive (n = 95 [47. 5%]), while samples that were nonreactive in two of the three assays were considered CMV DNA negative (n = 105 [52.5%]). Using the LightCycler assay, CMV DNA was detected in 91 of the 95 CMV DNA-positive human specimens (sensitivity, 95.8%; 95% confidence interval [CI], 89.6 to 98.8) and in 1 of the CMV DNA-negative specimens (specificity, 99%; 95% CI, 94.8 to 99.8). Results of CMV load determination as assessed by both quantitative test systems were correlated (r = 0.73; P < 0.0001; 95% CI, 0.61 to 0.81). Results for undiluted samples containing a high CMV load were more accurate with the LightCycler test than were results obtained with the CACM test, which underestimated the viral load of samples containing high DNA copy numbers. The high level of sensitivity, specificity, accuracy, and rapidity provided by the LightCycler technology are favorable for the use of this system in the detection of CMV DNA in clinical specimens.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Citomegalovirus/isolamento & purificação , DNA Viral/sangue , DNA Viral/urina , Reação em Cadeia da Polimerase/métodos , Citomegalovirus/genética , Infecções por Citomegalovirus/virologia , Humanos , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade
14.
Med Microbiol Immunol ; 189(1): 13-8, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11034553

RESUMO

Stimulation of Epstein-Barr virus (EBV) genome-positive Burkitt lymphoma cells with the ganglioside IV3NeuAc-nLcOse4Cer leads to the induction of cell differentiation processes and activates the EBV lytic viral cycle. In cells of the Burkitt lymphoma line Raji differential expression of host cell genes was analysed in the early phase (150 min) post stimulation with the ganglioside to display the cell activities that precede the activation of the EBV lytic cycle using the differential display reverse transcription-polymerase chain reaction technique. Multiple fragment cDNAs derived from control cells and ganglioside-stimulated cells were amplified using random primers and displayed via polyacrylamide gel electrophoresis. The expression pattern of 8,400 bands was analysed. Eleven differentially expressed fragment cDNAs were reamplified and identified by nucleotide sequencing. Six of these could be identified as coding for proteins that may take part in virus reactivation and differentiation. The most striking finding was the induction of s-adenosylhomocysteine hydrolase (AHCY) expression. The cellular enzyme AHCY plays an important role in transmethylation reactions controlling the replication of several viruses. Thus. an involvement in EBV replication can be suggested.


Assuntos
Gangliosídeos/farmacologia , Herpesvirus Humano 4/genética , Hidrolases/genética , Adenosil-Homocisteinase , Ciclo Celular , Linhagem Celular Transformada , DNA Complementar/análise , DNA Viral/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Herpesvirus Humano 4/efeitos dos fármacos , Humanos , Hidrolases/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ativação Transcricional , Ativação Viral
15.
Virus Res ; 68(1): 63-9, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10930663

RESUMO

LMP1 is a genuine oncogene encoded by the Epstein-Barr virus (EBV). The cellular response to expression of the EBV-encoded gene LMP1 in the epithelial cell line Wish was studied. Cells were stably transfected with pCEP-LMP, an expression vector for LMP1. On transcript level a transient expression of the LMP1-gene with a maximum 2 days post transfection was observed. Six days post transfection the rate of DNA synthesis of LMP1-transfected Wish cells was increased by 80% compared to control cells, after 2 further days the number of cells was increased by 32%. A human cDNA-array was screened with probes from LMP1-transfected and control cells showing induction of transcription for proliferation associated genes and repression for growth suppressor genes.


Assuntos
Células Epiteliais/fisiologia , Células Epiteliais/virologia , Regulação da Expressão Gênica , Herpesvirus Humano 4/metabolismo , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/metabolismo , Divisão Celular , Linhagem Celular , DNA/biossíntese , Herpesvirus Humano 4/genética , Humanos , Biossíntese de Proteínas , Transcrição Gênica , Transfecção
16.
Biochim Biophys Acta ; 1492(1): 139-44, 2000 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-10858540

RESUMO

Stimulation by the ganglioside IV(3)NeuAc-nLcOse(4)Cer leads to growth arrest in the Burkitt lymphoma cell line Raji. In order to analyze the primary response of Raji cells to that stimulus, a cDNA array screen and a suppression subtractive hybridization-PCR approach were performed. Twenty-four genes with assigned functions were confirmed to be induced by the ganglioside in reverse Northern blot experiments covering e.g. protein kinase B, phospholipase C, the MAP-kinase ERK3, the transcription factors YY1, DR1 and NSEP, the membrane traffic protein TAP, and the nuclear export protein CRM1. Most of the genes identified are involved in signal transduction, transcription, and cell trafficking. For selected genes, the induction of expression was quantified by semiquantitative RT-PCR.


Assuntos
Linfoma de Burkitt/patologia , Movimento Celular/efeitos dos fármacos , Gangliosídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Linfoma de Burkitt/genética , Divisão Celular/efeitos dos fármacos , Divisão Celular/genética , Movimento Celular/genética , Transformação Celular Neoplásica , Replicação do DNA/efeitos dos fármacos , DNA Complementar/efeitos dos fármacos , DNA Complementar/isolamento & purificação , Genes Neoplásicos/efeitos dos fármacos , Genes Neoplásicos/genética , Humanos , Transdução de Sinais/genética , Células Tumorais Cultivadas
17.
Infection ; 28(1): 30-3, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10697788

RESUMO

GB virus C/hepatitis G virus (GBV-C/HGV) is a recently discovered flavivirus of still unknown pathogenic relevance. We examined traumatologic outpatients to determine GBV-C/HGV viremia for further epidemiological studies, as blood donors hitherto used as controls represent healthy individuals without risk factors. Anti-GBV-C/HGV antibodies were detectable in 13.2% (95% confidence interval [CI] 9.3-18.2) and GBV-C/HGV RNA was detectable in 4.5% (95% CI 2.4-8.2) of the outpatients. In chronic non-A-E hepatitis patients GBV-C/HGV viremia was detectable at a significantly higher level of 16.1% (95% CI 6.1-34.5), while the prevalence of anti-GBV-C/HGV antibodies was 12.9% (95% CI 4.2-30.8). The rate of GBV-C/HGV viremia in patients with malignant diseases (different types of tumors, blood recipients were excluded) was 12.5% (95% CI 8.4-18.1), a significant elevation compared to traumatologic outpatients. The seroprevalence in the tumor group was 22.1% (95% CI 16.7-28.6), also significantly elevated. Thus, there are two messages. Firstly, testing for GBV-C/HGV may be a useful extension of the diagnostic procedure of viral hepatitis. Secondly, common risk factors or etiologic relations of GBV-C/HGV and extrahepatic malignancies should be discussed.


Assuntos
Flaviviridae , Hepatite Viral Humana/epidemiologia , Neoplasias/virologia , Ferimentos e Lesões , Adulto , Anticorpos Antivirais/análise , Feminino , Flaviviridae/imunologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Prevalência , RNA Viral/análise , Fatores de Risco
19.
Planta ; 209(1): 13-24, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10467027

RESUMO

The enzyme sucrose synthase (UDP-glucose: D-fructose 2alpha-glucosyltransferase, EC 2.4.1.13) is a key enzyme in carbohydrate metabolism, catalyzing the reversible conversion of sucrose uridine-diphosphate into fructose and UDP-glucose. We report the molecular characterization of two classes of cDNA and genomic clones encoding sucrose synthase from Craterostigma plantagineum Hochst., a resurrection plant in which the turnover of sucrose is considered to have an important role in the unique phenomenon of surviving desiccation. Sucrose-synthase transcript and protein levels are modulated by dehydration and rehydration. In-situ hybridization revealed that transcripts preferentially accumulate in phloem tissues. Promoter analysis underlined a role for class-I sucrose-synthase genes in dehydration stress and in response to cis-abscisic acid. A DNA sequence motif common to class-I sucrose-synthase and sucrose-phosphate-synthase genes was discovered.


Assuntos
Glucosiltransferases/genética , Plantas/enzimologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA de Plantas , Glucosiltransferases/classificação , Glucosiltransferases/isolamento & purificação , Dados de Sequência Molecular , Plantas/genética , Plantas Geneticamente Modificadas , Plantas Tóxicas , Regiões Promotoras Genéticas , RNA Mensageiro , Coelhos , Homologia de Sequência de Aminoácidos
20.
IUBMB Life ; 48(3): 353-8, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10690651

RESUMO

Two acidic glycosphingolipids (gangliosides) derived from mouse macrophage membranes and separated by thin-layer chromatography have a strong cytostatic effect on human and mouse tumor cells. The structure of the two gangliosides, named M phi G1 and M phi G2, was elucidated by application of physicochemical and immunochemical methods. Gas chromatography and mass spectrometry of M phi G1 and M phi G2 classified them as isomeric monosialogangliosides with ceramide moieties composed of sphingosine as the long-chain base, C16 and C18 fatty acids, respectively, and a lacto-tetraose backbone. For M phi G1, additional immunochemical findings led to the proposed structure IV3NeuAc-nLcOse4Cer. The immunochemical reactions of M phi G2 suggest a branched structure for the oligosaccharide moiety.


Assuntos
Glicoesfingolipídeos/análise , Macrófagos Peritoneais/metabolismo , Animais , Glicoesfingolipídeos/metabolismo , Humanos , Ativação de Macrófagos , Camundongos , Tioglicolatos
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