TTV and other anelloviruses: The astonishingly wide spread of a viral infection

The broad family of viruses known as anelloviruses (AV) infects both humans and numerous animal species. They have a tiny, covalently closed single-stranded DNA genome and the astonishing capacity to infect a very high percentage of healthy and ill people with chronic infections that could last a lifetime. AV, and particularly the prototype Torquetenovirus, have established a successful interaction with the host's immune system and the rate at which they replicate is a gauge to measure overall immune function, even though many aspects of their life cycle and pathogenesis are still poorly understood

Simultaneous control of DNA and RNA processing efficiency using a nucleic acid calibration set.

PCR-based detection techniques enables reliable and sensitive nucleic acid target detection. However, quantitative determination methods often fail to control for the efficiency of nucleic acid extraction, reverse transcription, and PCR amplification. This problem is even more prominent when working with clinical samples due to target sequence loss during nucleic acid processing or the co-purification of PCR inhibitors (1,2). Handling processes are often assumed to approach 100% efficiency in the laboratory, even if practical experience shows that this efficiency can be much lower. This inability to ensure accuracy can lead to significant error in uncalibrated DNA sample quantitation. The additional need for reverse transcription of RNA may further increase the quantitative error rate, as yet another enzymatic process is involved. Nucleic acid controls have been developed based upon known sequences to calibrate either DNA or RNA handling; DNA calibrators have been used to control for the amplification of target sequences using realtime PCR methods (3–8), while RNA calibrators have been developed to test reverse transcription and amplification efficiencies (9–11). A nonpathogenic viral particle carrying a sequence for use as an external positive control of extraction and amplification has also been described (12). Unfortunately, most of the established processing controls are only suitable for limited applications (i.e., either DNA or RNA detection). Cross-contamination of biological samples or minute detection from natural sources reveals the need for completely synthetic sequences, with no homology to sequences in the nucleic acid databases. It is, therefore, beneficial to design an internal, synthetic calibration system that can control for both DNA and RNA processing steps in a single tube. This set includes both RNA and DNA targets with identical primer binding sites and, thus, primer binding efficiency, but easily distinguishable sequence characteristics, allowing for simultaneous detection, quantitation, and calibration of nucleic acid processing efficiency. A 150-bp randomly generated nucleic acid sequence was developed for use as a short control (SC). A GCrich 75-bp sequence was inserted in the middle of the 150-bp sequence to generate a 225-bp sequence, long control (LC). Besides size, the two sequences were designed to have easily distinguishable probe binding sites with a predicted product melting temperature difference of 4°C. Calibrator sequences have been published as GenBank® accession nos. EF143258 (DNA control, LC) and EF143257 (RNA control, SC). Simultaneous control of DNA and RNA processing efficiency using a nucleic acid calibration se

Orthopoxvirus Seroprevalence in Cats and Veterinary Personnel in North-Eastern Italy in 2011

Orthopoxviruses (OPV) are emerging zoonotic pathogens, and an increasing number of human infections is currently reported in Europe and in other continents, warranting heightened attention on this topic. Following two OPV infections reported in veterinarians scratched by sick cats in 2005 and 2007 in North-Eastern-Italy, involving a previously undescribed OPV, a similar strain was isolated by a sick cat from the same territory in 2011, i.e., 6 years later, raising attention on OPV circulation in this region. A surveillance program was launched to assess the OPV seroprevalence among the veterinarians working in local veterinary clinics and in the local wild and domestic cat population; seroprevalence was 33.3% in veterinarians and 19.5% in cats. Seroprevalence in cats was unevenly distributed, peaking at 40% in the area where OPV-infected cats had been observed

Performance of rapid tests in the management of dengue fever imported cases in Lazio, Italy 2014-2019

Abstract Background In Italy, dengue virus is the most frequent agent of imported viral infections. The use of rapid diagnostic tests (RDTs) may be of help as a preliminary user-friendly quick assay to facilitate dengue diagnosis, as ordinary laboratory diagnosis of dengue fever may require special efforts in terms of tools availability, interpretation of results, and skilled personnel. The performance of RDTs, however, may vary according to different epidemiological and laboratory background. Methods We reviewed five years of laboratory records of two dengue RDT results (Colorimetric SD-Bioline Dengue-Duo-RDT and Fluorimetric SD-Biosensor-STANDARD-F-Dengue-RDT), able to detect viral NS1 antigen and specific IgM and IgG. Diagnostic parameters were calculated using as reference the results of molecular (RT-PCR) and serological (immunofluorescence, IFA) tests. Overall performance, calculated considering the final case definition, was included in the accuracy assessment of RDTs. Results The combined use of NS1 and IgM/IgG RDT for the detection of acute dengue cases resulted in an overall sensitivity and specificity of 87.2% and 97.9% for Colorimetric RDT, 96.2% and 96.2% for Fluorimetric RDT. NS1 was the most reliable marker of acute infection, while IgM resulted falsely positive in nine samples, including sera derived from 2 Zika and 4 non-arbovirus infected patients. Conclusions The inclusion of RDT in the diagnostic algorithm is of undeniable help in the prompt management and surveillance of dengue infection in non-endemic areas. Confirmatory tests are, however, necessary to rule in or rule out dengue fever diagnosis

Zika virus NS2A inhibits interferon signaling by degradation of STAT1 and STAT2

The Interferon (IFN) response is crucial to restrain pathogenic infections. Investigations into flavivirus-host interactions reported that the high virulence is linked to innate immune evasion. Zika Virus (ZIKV) has developed diversified strategies to evade the innate immune system. We report that the viral protein NS2A counteracts the IFN response by strongly suppressing the IFN signaling. NS2A targets transcription factors STAT1 and STAT2, to impede their nuclear localization, thereby suppressing the transcription of ISRE promoter and IFN-stimulated genes. We found that NS2A promotes degradation of STAT1 and STAT2. Treatment of NS2A transfected cells with MG132 restores the levels of both transcription factors, suggesting the involvement of the proteasome system. Given the impact that the IFN antagonism has on flavivirus virulence, the knowledge gained by characterizing the mechanism through which ZIKV evades the IFN response paves the ground for new strategies to attenuate the pathogenesis and to develop countermeasures against effective pharmacological targets

Locally advanced leiomyosarcoma of the spleen. A case report and review of the literature

<p>Abstract</p> <p>Background</p> <p>Leiomyosarcomas are rare tumours, predominantly localized in the stomach, small intestine and retroperitoneum. Only one case of primary leiomyosarcoma of the spleen is described in human beings in literature.</p> <p>Case presentation</p> <p>We report a case of locally advanced primary leiomyosarcoma of the spleen in a 54 year-old woman, diagnosed only after splenectomy, performed with the suspicion of splenic haematoma.</p> <p>Conclusion</p> <p>Due to the lack of cases, no specific chemotherapy regimen has been tested to provide a longer survival.</p

Full-length genome sequence of a dengue serotype 1 virus isolate from a traveler returning from Democratic Republic of Congo to Italy, July 2019.

Abstract We report the full-genome sequence of a Dengue serotype-1 virus (DENV-1) isolated from a traveller returning in July 2019 to Italy from Democratic Republic of Congo (DRC), which is currently affected by Ebola and measles outbreaks. The sequence shows high similarity with two 2013 strains isolated in Angola and China