250 research outputs found
First sequence-confirmed case of infection with the new influenza A(H1N1) strain in Germany
Here, we report on the first sequence-confirmed case of infection with the new influenza A(H1N1) virus in Germany. Two direct contacts of the patient were laboratory-confirmed as cases and demonstrate a chain of direct human-to-human transmission
The Florida Current at Key West: Summer 1972
Sixteen dropsonde cross-sections of the Florida Straits at the Key West, Florida, longitude are used to examine the persistent features and large-scale variations of the temperature, salinity, and horizontal velocity structures of the Florida Current. A persistent counterflow was found along the northern shore of the Current, which can be interpreted from the salinity distribution as cyclonic recirculation of the Florida Current water. Analysis of the temporal variations indicate that a downstream acceleration of the Current is accompanied by a warming trend
Analysis of an ankyrin-like region in Epstein Barr Virus encoded (EBV) BZLF-1 (ZEBRA) protein: implications for interactions with NF-κB and p53
Epstein–Barr virus in the multiple sclerosis brain: a controversial issue—report on a focused workshop held in the Centre for Brain Research of the Medical University of Vienna, Austria
Recent epidemiological and immunological studies provide evidence for an association between Epstein–Barr virus infection and multiple sclerosis, suggesting a role of Epstein–Barr virus infection in disease induction and pathogenesis. A key question in this context is whether Epstein–Barr virus-infected B lymphocytes are present within the central nervous system and the lesions of patients with multiple sclerosis. Previous studies on this topic provided highly controversial results, showing Epstein–Barr virus reactivity in B cells in the vast majority of multiple sclerosis cases and lesions, or only exceptional Epstein–Barr virus-positive B cells in rare cases. In an attempt to explain the reasons for these divergent results, a workshop was organized under the umbrella of the European Union FP6 NeuroproMiSe project, the outcome of which is presented here. This report summarizes the current knowledge of Epstein–Barr virus biology and shows that Epstein–Barr virus infection is highly complex. There are still major controversies, how to unequivocally identify Epstein–Barr virus infection in pathological tissues, particularly in situations other than Epstein–Barr virus-driven lymphomas or acute Epstein–Barr virus infections. It further highlights that unequivocal proof of Epstein–Barr virus infection in multiple sclerosis lesions is still lacking, due to issues related to the sensitivity and specificity of the detection methods
Population-based study of the durability of humoral immunity after SARS-CoV-2 infection
SARS-CoV-2 antibody quantity and quality are key markers of humoral immunity. However, there is substantial uncertainty about their durability. We investigated levels and temporal change of SARS-CoV-2 antibody quantity and quality. We analyzed sera (8 binding, 4 avidity assays for spike-(S-)protein and nucleocapsid-(N-)protein; neutralization) from 211 seropositive unvaccinated participants, from the population-based longitudinal TiKoCo study, at three time points within one year after infection with the ancestral SARS-CoV-2 virus. We found a significant decline of neutralization titers and binding antibody levels in most assays (linear mixed regression model, p<0.01). S-specific serum avidity increased markedly over time, in contrast to N-specific. Binding antibody levels were higher in older versus younger participants – a difference that disappeared for the asymptomatic-infected. We found stronger antibody decline in men versus women and lower binding and avidity levels in current versus never-smokers. Our comprehensive longitudinal analyses across 13 antibody assays suggest decreased neutralization-based protection and prolonged affinity maturation within one year after infection
Epigenetic mechanisms in virus-induced tumorigenesis
About 15–20% of human cancers worldwide have viral etiology. Emerging data clearly indicate that several human DNA and RNA viruses, such as human papillomavirus, Epstein–Barr virus, Kaposi’s sarcoma-associated herpesvirus, hepatitis B virus, hepatitis C virus, and human T-cell lymphotropic virus, contribute to cancer development. Human tumor-associated viruses have evolved multiple molecular mechanisms to disrupt specific cellular pathways to facilitate aberrant replication. Although oncogenic viruses belong to different families, their strategies in human cancer development show many similarities and involve viral-encoded oncoproteins targeting the key cellular proteins that regulate cell growth. Recent studies show that virus and host interactions also occur at the epigenetic level. In this review, we summarize the published information related to the interactions between viral proteins and epigenetic machinery which lead to alterations in the epigenetic landscape of the cell contributing to carcinogenesis
Analysis of Epstein-Barr virus reservoirs in paired blood and breast cancer primary biopsy specimens by real time PCR
INTRODUCTION: Epstein-Barr virus (EBV) is present in over 90% of the world's population. This infection is considered benign, even though in limited cases EBV is associated with infectious and neoplastic conditions. Over the past decade, the EBV association with breast cancer has been constantly debated. Adding to this clinical and biological uncertainty, different techniques gave contradictory results for the presence of EBV in breast carcinoma specimens. In this study, minor groove binding (MGB)-TaqMan real time PCR was used to detect the presence of EBV DNA in both peripheral blood and tumor samples of selected patients. METHODS: Peripheral blood and breast carcinoma specimens from 24 patients were collected. DNA was extracted and then amplified by MGB-TaqMan real time PCR. RESULTS: Of 24 breast tumor specimens, 11 (46%) were positive for EBV DNA. Of these 11 breast tumor specimens, 7 (64%) were also positive for EBV DNA in the peripheral blood, while 4 (36%) were positive for EBV DNA in the tumor, but negative in the blood. CONCLUSION: EBV was found at extremely low levels, with a mean of 0.00004 EBV genomes per cell (range 0.00014 to 0.00001 EBV genomes per cell). Furthermore, our finding of the presence of EBV in the tumor specimens coupled to the absence of detection of EBV genomic DNA in the peripheral blood is consistent with the epithelial nature of the virus. Because of the low levels of viral DNA in tumor tissue, further studies are needed to assess the biological input of EBV in breast cancer
Detection of influenza A(H1N1)v virus by real-time RT-PCR.
Influenza A(H1N1)v virus was first identified in April 2009. A novel real-time RT-PCR for influenza A(H1N1)v virus was set up ad hoc and validated following industry-standard criteria. The lower limit of detection of the assay was 384 copies of viral RNA per ml of viral transport medium (95% confidence interval: 273-876 RNA copies/ml). Specificity was 100% as assessed on a panel of reference samples including seasonal human influenza A virus H1N1 and H3N2, highly pathogenic avian influenza A virus H5N1 and porcine influenza A virus H1N1, H1N2 and H3N2 samples. The real-time RT-PCR assay for the influenza A matrix gene recommended in 2007 by the World Health Organization was modified to work under the same reaction conditions as the influenza A(H1N1)v virus-specific test. Both assays were equally sensitive. Clinical applicability of both assays was demonstrated by screening of almost 2,000 suspected influenza (H1N1)v specimens, which included samples from the first cases of pandemic H1N1 influenza imported to Germany. Measuring influenza A(H1N1)v virus concentrations in 144 laboratory-confirmed samples yielded a median of 4.6 log RNA copies/ml. The new methodology proved its principle and might assist public health laboratories in the upcoming influenza pandemic
Myelodysplastic syndrome (MDS) as a late stage of subclinical hemophagocytic lymphohistiocytosis (HLH): A putative role forLeptospirainfection. A hypothesis
It is proposed that hemophagocytic lymphohistiocytosis (HLH) and myelodysplastic syndromes (MDS) may be temporally distinct phases of patho-physiologically related disease processes. A significant subgroup of MDS may develop from subclinical HLH. In that case, HLH-like disease would chronically proceed with little disease activity or under occasional flares only, until it first becomes clinically apparent at the MDS stage. At the MDS stage, however, HLH activity may be easily overlooked by histological or cytogenetic means, since hemophagocytosis has fallen already largely silent. Current treatment options for HLH, like high-dose intravenous immunoglobulins (IVIG), may turn out to be helpful in MDS patients as well. In rare and extreme cases, Leptospira infection causes severe and life-threatening HLH. Thus, this proposal also implies that an insufficient, dysfunctional or misdirected immunological response to Leptospira infection may lead to MDS in the long run in a significant number of cases, which have not been recognized as Leptospira-triggered events in the first place. Infections by agents other than Leptospira may lead to subclinical HLH-like disease with MDS as a late stage as well
Myelodysplastic syndrome (MDS) as a late stage of subclinical hemophagocytic lymphohistiocytosis (HLH): A putative role for Leptospira infection. A hypothesis
It is proposed that hemophagocytic lymphohistiocytosis (HLH) and myelodysplastic syndromes (MDS) may be temporally distinct phases of pathophysiologically related disease processes. A significant subgroup of MDS may develop from subclinical HLH. In that case, HLH-like disease would chronically proceed with little disease activity or under occasional flares only, until it first becomes clinically apparent at the MDS stage. At the MDS stage, however, HLH activity may be easily overlooked by histological or cytogenetic means, since hemophagocytosis has fallen already largely silent. Current treatment options for HLH, like high-dose intravenous immunoglobulins (IVIG), may turn out to be helpful in MDS patients as well.In rare and extreme cases, Leptospira infection causes severe and life-threatening HLH. Thus, this proposal also implies that an insufficient, dysfunctional or misdirected immunological response to Leptospira infection may lead to MDS in the long run in a significant number of cases, which have not been recognized as Leptospira-triggered events in the first place. Infections by agents other than Leptospira may lead to subclinical HLH-like disease with MDS as a late stage as well
- …
