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51.
BK virus is the causative agent of polyomavirus-associated nephropathy, a major cause of kidney transplant failure affecting 1%-10% of recipients. Previous studies that investigated the viral source on the kidney recipient pointed that the donor is implicated in the origin of human polyomavirus BK (BKPyV) infection in recipients, but giving the low genetic variability of BKPyV this subject is still controversial. The aim of this study was to determine if BKPyV replicating in kidney recipients after transplantation is always originated from the donor. Urine and blood samples from 68 pairs of living donors and kidney recipients who underwent renal transplantation from August 2010-September 2011 were screened for BKPyV by real time polymerase chain reaction. Only three recipients presented viremia. When both donors and recipients were BKPyV positive, a larger fragment of VP1 region was obtained and sequenced to determine the level of similarity between them. A phylogenetic tree was built for the 12 pairs of sequences obtained from urine and high level of similarity among all sequences was observed, indicating that homology inferences for donor and recipient viruses must be cautiously interpreted. However, a close inspection on the donor-recipient pairs sequences revealed that 3 of 12 pairs presented considerably different viruses and 4 of 12 presented mixed infection, indicating that the source of BKPyV infection is not exclusively derived from the donor. We report that about 60% of the renal recipients shed BKPyV genetically distinct from the donor, confronting the accepted concept that the donor is the main source of recipients’ infection.  相似文献   
52.
Infection with human papillomavirus (HPV) is the main cause of cervical cancer. Viral persistence is considered the main risk factor for neoplastic progression and evidence suggests that regulatory T cells (Treg) play an important role in the failure of viral elimination. The aim of this study was to detect phenotypic markers of Treg and cytokines interleukin (IL)-10 and transforming growth factor (TGF)-β, in the cervical microenvironment of HPV-infected patients. One hundred and one samples of uterine cervix embedded in paraffin were analyzed. We used immunohistochemistry to examine the coexpression of the CD25/FOXP3 and CD4/TGF-β markers, and the expression of GITR and IL-10 in cells present in the cervical stroma. We detected a microenvironment composed of high proportions of CD25+FOXP3+, CD4+TGFβ+, IL-10+, and GITR+ cells in samples with high viral loads and severe lesions of HPV-infected patients. The abundance of these markers, indicative of the presence of Treg cells and immunosuppressive cytokines, was significantly associated with severe lesions and elevated viral loads in the examined samples. These results suggest that Treg cells may be involved in maintaining a microenvironment favorable for viral persistence and neoplastic progression. Our findings support those of previous studies that suggested that these markers could be used to predict HPV persistence and neoplastic progression, and as potential targets for immune response modulation.  相似文献   
53.
54.
Ioana Agache  Isabella Annesi‐Maesano  Andreas Bonertz  Francesco Branca  Andrew Cant  Zlatko Fras  Frank Ingenrieth  Leyla Namazova‐Baranova  Mikaela Odemyr  Antonio Spanevello  Stefan Vieths  Arzu Yorgancioglu  Montserat Alvaro‐Lozano  Domingo Barber Hernandez  Toms Chivato  Stefano Del Giacco  Zuzana Diamant  Ibon Eguiluz‐Gracia  Roy Gert van Wijk  Philippe Gevaert  Anke Graessel  Peter Hellings  Karin Hoffmann‐Sommergruber  Marek Jutel  Susanne Lau  Antti Lauerma  Jose Maria Olaguibel  Liam O'Mahony  Cevdet Ozdemir  Oscar Palomares  Oliver Pfaar  Joaquin Sastre  Glennis Scadding  Carsten Schmidt‐Weber  Peter Schmid‐Grendelmeier  Mohamed Shamji  Isabel Skypala  Monica Spinola  Otto Spranger  Maria Torres  Andrea Vereda  Sergio Bonini 《Allergy》2019,74(11):2064-2076
The European Academy of Allergy and Clinical Immunology (EAACI) organized the first European Strategic Forum on Allergic Diseases and Asthma. The main aim was to bring together all relevant stakeholders and decision‐makers in the field of allergy, asthma and clinical Immunology around an open debate on contemporary challenges and potential solutions for the next decade. The Strategic Forum was an upscaling of the EAACI White Paper aiming to integrate the Academy's output with the perspective offered by EAACI's partners. This collaboration is fundamental for adapting and integrating allergy and asthma care into the context of real‐world problems. The Strategic Forum on Allergic Diseases brought together all partners who have the drive and the influence to make positive change: national and international societies, patients’ organizations, regulatory bodies and industry representatives. An open debate with a special focus on drug development and biomedical engineering, big data and information technology and allergic diseases and asthma in the context of environmental health concluded that connecting science with the transformation of care and a joint agreement between all partners on priorities and needs are essential to ensure a better management of allergic diseases and asthma in the advent of precision medicine together with global access to innovative and affordable diagnostics and therapeutics.  相似文献   
55.
Immunologic Research - The impairment of regulatory T cells (Tregs) is a characteristic feature of autoimmune hepatitis (AIH), and the degradation of tryptophan (Trp) to kynurenine (Kyn), by gamma...  相似文献   
56.

Efficient and sensitive diagnostic tools are essential for the study of the eco-epidemiology of Echinococcus species. We evaluated an automated magnetic bead-based DNA extraction commercial kit followed by qPCR (MB-qPCR), for the detection of Echinococcus multilocularis and Echinococcus canadensis in coyote (Canis latrans) fecal samples. The diagnostic sensitivity was determined by validating the method against the scraping, filtration, and counting technique (SFCT) for samples collected in Canada. From the 60 samples tested, 27 out of 31 SFCT positives samples for Echinococcus cestodes were positive in the MB-qPCR for E. multilocularis, with a sensitivity of 87.1% (95% CI 70.2 to 96.4%). Two samples were also positive for E. canadensis in the MB-qPCR and confirmed by morphological identification of adult worms. The agreement of the MB-qPCR and the SFCT was statistically significant with a kappa value of 0.67 (95% CI 0.48–0.85; p value < 0.001). The magnetic bead-based DNA extraction followed by qPCR proved to have a sensitivity comparable to the SFCT to detect E. multilocularis. Although the diagnostic sensitivity for E. canadensis was not estimated, MB-qPCR identified E. canadensis cases previously overlooked when using SFCT. We propose a combination of molecular and morphological identification using the MB-qPCR and the SFCT to detect both parasites, allowing for a more efficient large-scale surveillance, and detecting co-infections of Echinococcus species that can be difficult to identify when only based on morphology.

  相似文献   
57.
Parasitology Research - It is known that premature elimination of non-parasitized RBCs (nRBCs) plays an important role in the pathogenesis of malarial anemia, in which suicidal death process...  相似文献   
58.
Parasitology Research - The treatment of cutaneous leishmaniasis in associated with several adverse effects and therapeutic failure, resulting in patients’ abandonment of treatment. Research...  相似文献   
59.

Blastocystis is a ubiquitous protozoan with a wide range of hosts. In humans, its presence has been associated with gastrointestinal disorders, although its role as a pathogen still needs to be elucidated. Until now, 17 Blastocystis subtypes (STs) have been identified, with ST1–ST4 the most commonly found in humans. Among domestic animals, the same STs reported in humans have been detected in dogs. An epidemiological survey on dog kennels was carried out to evaluate the prevalence of Blastocystis and the STs involved. Overall, 99 faecal samples were collected from the rescue shelters. Blastocystis detection was performed through conventional barcoding PCR targeting the 1800-bp SSU-rDNA, followed by sequencing and phylogenetic analysis. Blastocystis DNA was found in 21 faecal samples (21.2%), and all samples were successfully sequenced and identified as ST3 in a unique monophyletic group. The presence of Blastocystis was reported for the first time in dogs from Italy, with the identification of ST3, the subtype most commonly found in humans.

  相似文献   
60.
Intellectual disability in Down syndrome (DS) has been attributed to neurogenesis impairment during fetal brain development. Consistently with explicit memory alterations observed in children with DS, fetuses with DS exhibit neurogenesis impairment in the hippocampus, a key region involved in memory formation and consolidation. Recent evidence suggests that the subiculum plays a unique role in memory retrieval, a process that is also altered in DS. While much attention has been devoted to the hippocampus, there is a striking lack of information regarding the subiculum of individuals with DS and DS models. In order to fill this gap, in the current study, we examined the subiculum of fetuses with DS and of the Ts65Dn mouse model of DS. We found that in fetuses with DS (gestational week: 17–21), the subiculum had a reduced thickness, a reduced cell density, a reduced density of progenitor cells in the ventricular zone, a reduced percentage of neurons, and an increased percentage of astrocytes and of cells immunopositive for calretinin—a protein expressed by inhibitory interneurons. Similarly to fetuses with DS, the subiculum of neonate Ts65Dn mice was reduced in size, had a reduced number of neurons and a reduced number of proliferating cells. Results suggest that the developmental defects in the subiculum of fetuses with DS may underlie impairment in recall memory and possibly other functions played by the subiculum. The finding that the subiculum of the Ts65Dn mouse exhibits neuroanatomical defects resembling those seen in fetuses with DS further validates the use of this model for preclinical studies.  相似文献   
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