Changes of synapsin I messenger RNA expression during rat brain development

Synapsin I is a synaptic phosphoprotein that is involved in the short-term regulation of neurotransmitter release. In this report we present the first extensive study of the developmental expression of its corresponding messenger ribonucleic acid (mRNA) by in situ hybridization and northern blot analysis in rat brain. Synapsin I mRNA showed pronounced differences in expression in different brain regions during postnatal development. The early expression of synapsin I mRNA in ontogenetically older regions such as the thalamus, the piriform cortex and the hippocampus coincides with the earlier maturation of these regions, in contrast to its later expression in ontogenetically younger areas such as the cerebellum and the neocortex. An intriguing expression pattern was found in the hippocampus. In all hippocampal subregions synapsin I mRNA expression increased from postnatal day (PND) 1 to 17. After PND 17, however, there was a marked dissociation between persisting high expression levels in CA3 and the dentate gyrus and a strong decline in synapsin I mRNA expression in CA1. The persistence of synapsin I in some adult rat brain regions indicates that it plays a part in synapse formation during plastic adaption in neuronal connectivities.     

Development of a blocking enzyme-linked immunosorbent assay for the detection of avian polyomavirus-specific antibodies

Avian polyomavirus, described originally as budgerigar fledgling disease virus, has been associated with devastating contagious disease outbreaks in budgerigar aviaries. At present, this virus affects a wide range of psittacine and non-psittacine birds worldwide, and the serum neutralisation test is used for the serodiagnosis of avian polyomavirus infections. A blocking enzyme-linked immunosorbent assay was developed for the screening of large numbers of sera collected from various avian species. The assay employs a monoclonal antibody directed against the major structural protein VP1 as a blocking antibody in a sandwich blocking procedure. Either purified avian polyomavirus particles or avian polyomavirus VP1 expressed in recombinant baculovirus-infected Sf9 cells were used as antigen. The specificity of the blocking enzyme-linked immunosorbent assay was evaluated by testing sera directed against mammalian polyomaviruses. Using sera obtained from chicken infected experimentally with avian polyomavirus and a collection of psittacine field-origin sera, a good correlation was observed between the results of the blocking enzyme-linked immunosorbent assay and the serum neutralisation test. However, the blocking enzyme-linked immunosorbent assay is more rapid and more economic. Both, avian polyomavirus particles and VP1 produced by recombinant DNA technology proved to be suitable antigens.     

Das Hepatitis-E-Virus – ein zoonotisches Virus: Verbreitung, Übertragungswege und Bedeutung für die Lebensmittelsicherheit

Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Das Hepatitis-E-Virus (HEV) ist ein Erreger einer akuten Hepatitis beim Menschen. Darüber hinaus treten zunehmend auch...     

The simultaneous occurrence of human norovirus and hepatitis E virus in a Norway rat (Rattus norvegicus)

Wild rats can be reservoirs and vectors for several human pathogens. An initial RT-PCR screening of the intestinal contents of Norway rats trapped in the sewer system of Copenhagen, Denmark, for caliciviruses revealed the presence of a human norovirus in one of 11 rodents. Subsequent phylogenetic analysis of the ~4.0-kb 3′-terminus of the norovirus genome resulted in the identification of a recombinant GI.b/GI.6 strain. The simultaneous detection of hepatitis E virus-like particles in the feces of this rat by transmission electron microscopy was confirmed by RT-PCR and sequence determination, resulting in the identification of a novel rat hepatitis E virus.     

Small and large fiber sensory polyneuropathy in type 2 diabetes: Influence of diagnostic criteria on neuropathy subtypes

Diabetic polyneuropathy (DPN) can be classified based on fiber diameter into three subtypes: small fiber neuropathy (SFN), large fiber neuropathy (LFN), and mixed fiber neuropathy (MFN). We examined the effect of different diagnostic models on the frequency of polyneuropathy subtypes in type 2 diabetes patients with DPN. This study was based on patients from the Danish Center for Strategic Research in Type 2 Diabetes cohort. We defined DPN as probable or definite DPN according to the Toronto Consensus Criteria. DPN was then subtyped according to four distinct diagnostic models. A total of 277 diabetes patients (214 with DPN and 63 with no DPN) were included in the study. We found a considerable variation in polyneuropathy subtypes by applying different diagnostic models independent of the degree of certainty of DPN diagnosis. For probable and definite DPN, the frequency of subtypes across diagnostic models varied from: 1.4% to 13.1% for SFN, 9.3% to 21.5% for LFN, 51.4% to 83.2% for MFN, and 0.5% to 14.5% for non‐classifiable neuropathy (NCN). For the definite DPN group, the frequency of subtypes varied from: 1.6% to 13.5% for SFN, 5.6% to 20.6% for LFN, 61.9% to 89.7% for MFN, and 0.0% to 6.3% for NCN. The frequency of polyneuropathy subtypes depends on the type and number of criteria applied in a diagnostic model. Future consensus criteria should clearly define sensory functions to be tested, methods of testing, and how findings should be interpreted for both clinical practice and research purpose.     

An ORF1‐rearranged hepatitis E virus derived from a chronically infected patient efficiently replicates in cell culture

Hepatitis E is an increasingly reported disease in industrialized countries. Studies on the replication cycle of hepatitis E virus (HEV) are hampered due to the lack of efficient and robust cell culture systems for this virus. We describe the successful isolation of HEV derived from a chronically infected kidney transplant patient held under immunosuppressive therapy. Inoculation of serum sample 47832 onto the human lung carcinoma cell line A549 resulted in the replication of the virus as shown by RT‐qPCR. This novel human‐derived HEV strain is closely related to a wild boar‐derived genotype 3 strain, which did not replicate in A549 cells. It carries a 186 nucleotide insertion in the hypervariable ORF1‐region, derived from two parts of its ORF1. By passaging of the infected cells, a cell line continuously producing HEV particles was generated as demonstrated by RT‐qPCR, immuno‐electron microscopy, density gradient centrifugation and immunohistochemistry. Replication of the produced virus was demonstrated after its inoculation onto fresh A549 cells and two consecutive passages, whereas heating at 65 °C for 2 min abolished its infectivity. Several point mutations scattered along the whole genome were present in the HEV strain from the second passage; however, the ORF1 insertion was still present. Previously, cell culture isolation of two other HEV strains carrying insertions in their hypervariable regions, but originating from human ribosomal protein genes, has been described. The findings may indicate that cell culture adaptation of is mostly dependent on the length and position of the insertion, rather than from the sequence itself.     

A comparison of immunohistochemical staining for oestrogen receptor, progesterone receptor and HER-2 in breast core biopsies and subsequent excisions

AIMS: To compare immunohistochemical staining for oestrogen receptor, progesterone receptor and HER-2 between core biopsy and matched subsequent excisional specimens. METHODS: One hundred consecutive core biopsy cases and subsequent excisional specimens were retrieved and immunohistochemical staining performed. Proportion and intensity of staining for hormone receptors and HercepTest score were recorded for each case in a blinded fashion by the authors. RESULTS: Overall hormone receptor status was concordant between cores and excisions in 96.9% of cases. ER status was concordant between the core and excision in 95.8% of cases. The intensity of staining for ER was similar in both core and excision specimens. PR status was concordant in cores and excisions in 90.3% of cases. There was weaker PR staining in the excisional specimens when compared with the cores. HER-2 status was concordant in cores and excisions in 86.6% of cases. CONCLUSIONS: Hormone receptor staining produced similar results on core and excisional specimens, although a small number of additional hormone receptor positive cases could be detected by performing staining on a previously received core in the case of a negative result on the excisional specimen. HER-2 staining is less reproducible between cores and excisions, but the clinical significance of this observation remains to be tested.