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151.
Respiratory syncytial virus (RSV) is the most important virus mediating lower respiratory tract illness in infants and young children. RSV infection is associated with pulmonary inflammation and increased levels of substance P (SP), making the airways and leukocytes that express SP receptors susceptible to the proinflammatory effects of this peptide. This study examines combining neutralizing anti-F glycoprotein and anti-SP antibody treatment of RSV-infected BALB/c mice to inhibit RSV replication and inflammation associated with infection. BALB/c mice were prophylactically treated with antibody prior to RSV infection or were therapeutically treated at day 2 or 6 post-RSV infection. Prophylactic or therapeutic treatment with anti-SP antibodies promptly reduced pulmonary inflammatory cell infiltration and decreased the number of cells expressing proinflammatory cytokines, while anti-F antibody treatment reduced virus titers. The results suggest that combined anti-viral and anti-SP antibody treatment may be effective in treating RSV disease.  相似文献   
152.
Using the type III restriction-modification enzyme EcoP15I, we isolated sequences flanking sites digested by the methylation-sensitive HpaII enzyme or its methylation-insensitive MspI isoschizomer for massively parallel sequencing. A novel data transformation allows us to normalise HpaII by MspI counts, resulting in more accurate quantification of methylation at >1.8 million loci in the human genome. This HELP-tagging assay is not sensitive to sequence polymorphism or base composition and allows exploration of both CG-rich and depleted genomic contexts.  相似文献   
153.
We report abnormal maternal laboratory parameters in twin-to-twin transfusion syndrome (TTTS) at mid-pregnancy. A retrospective chart review was undertaken of 109 patients with TTTS evaluated for placental laser surgery. Complete blood count (CBC), blood type and Rh factor, urine analysis and serum chemistry panel were obtained preoperatively, with the CBC and serum albumin repeated on the first postoperative day. The mean gestational age was 21.2+/-1.7 weeks. Initial abnormal values included hematocrit (32.1+/-3.0%), hemoglobin (11.0+/-1.03 g/dl), serum magnesium (1.71+/-0.17 mg/dl), total protein (6.08+/-0.55 g/dl) and albumin (3.06+/-0.34 g/dl). Despite minimal blood loss and conservative fluid replacement mean hematocrit, hemoglobin, and albumin were 27.3+/-2.74%, 9.3+/-0.94 g/dl and 2.56+/-0.23 g/dl, respectively on postoperative day one. Weight gain (8.0+/-5.5 lb.) and low urinary output were characteristic peri-operative events. Maternal hypoproteinemia and anemia occur in TTTS at mid-pregnancy. This may contribute independently to amniotic fluid production rates in the fetuses, and explain in part the maternal sensitivity to intravenous fluids in multiple pregnancy.  相似文献   
154.

Background  

The Picornaviridae family contains a number of important pathogenic viruses, among which the recently reclassified human parechoviruses (HPeVs). These viruses are widespread and can be grouped in several types. Understanding the evolutionary history of HPeV could answer questions such as how long the circulating lineages last shared a common ancestor and how the evolution of this viral species is shaped by its population dynamics. Using both strict and relaxed clock Bayesian phylogenetics we investigated 1) the substitutions rates of the structural P1 and capsid VP1 regions and 2) evolutionary timescale of currently circulating HPeV lineages.  相似文献   
155.
156.
Several studies have established an association between diabetes and alterations in bone metabolism; however, the underlying mechanism is not well established. Although zinc is recognized as a potential preventive agent against diabetes-induced bone loss, there is no evidence demonstrating its effect in chronic diabetic conditions. This study evaluated the effects of zinc supplementation in a chronic (90 days) type 1 diabetes-induced bone-loss model. Male Wistar rats were distributed in three groups: control, type 1 diabetes mellitus (T1DM), and T1DM plus zinc supplementation (T1DMS). Serum biochemical analysis; tibia histomorphometric, biomechanical, and collagen-content analyses; and femur mRNA expression were evaluated. Relative to T1DM, the zinc-supplemented group showed increased histomorphometric parameters such as TbWi and BAr and decreased TbSp, increased biomechanical parameters (maximum load, stiffness, ultimate strain, and Young’s modulus), and increased type I collagen content. Interestingly, similar values for these parameters were observed between the T1DMS and control groups. These results demonstrate the protective effect of zinc on the maintenance of bone strength and flexibility. In addition, downregulation of OPG, COL1A, and MMP-9 genes was observed in T1DMS, and the anabolic effects of zinc were evidenced by increased OC expression and serum ALP activity, both related to osteoblastogenesis, demonstrating a positive effect on bone formation. In contrast, T1DM showed excessive bone loss, observed through reduced histomorphometric and biomechanical parameters, characterizing diabetes-associated bone loss. The bone loss was also observed through upregulation of OPG, COL1A, and MMP-9 genes. In conclusion, zinc showed a positive effect on the maintenance of bone architecture and biomechanical parameters. Indeed, OC upregulation and control of expression of OPG, COL1A, and MMP-9 mRNAs, even in chronic hyperglycemia, support an anabolic and protective effect of zinc under chronic diabetic conditions. Furthermore, these results indicate that zinc supplementation could act as a complementary therapy in chronic T1DM.  相似文献   
157.
Diabetes mellitus is a chronic disease that affects over 382 million people worldwide. Type-1 Diabetes (T1D) is classified as an autoimmune disease that results from pancreatic β-cell destruction and insulin deficiency. Type-2 Diabetes (T2D) is characterized principally by insulin resistance in target tissues followed by decreased insulin production due to β-cell failure. It is challenging to identify immunological markers such as inflammatory molecules that are triggered in response to changes during the pathogenesis of diabetes. APRIL is an important member of the TNF family and has been linked to chronic inflammatory processes of various diseases since its discovery in 1998. Therefore, this study aimed to evaluate APRIL serum levels in T1D and T2D. For this, we used the ELISA assay to measure serum APRIL levels of 33 T1D and 30 T2D patients, and non-diabetic subjects as control group. Our data showed a decrease in serum APRIL levels in T1D patients when compared with healthy individuals. The same pattern was observed in the group of T2D patients when compared with the control. The decrease of serum APRIL levels in diabetic patients suggests that this cytokine has a role in T1D and T2D. Diabetes is already considered as an inflammatory condition with different cytokines being implicated in its physiopathology. Our data suggest that APRIL can be considered as a potential modulating cytokine in the inflammatory process of diabetes.  相似文献   
158.
The release of extracellular vesicles (EV) by fungal organisms is considered an alternative transport mechanism to trans‐cell wall passage of macromolecules. Previous studies have revealed the presence of EV in culture supernatants from fungal pathogens, such as Cryptococcus neoformans, Histoplasma capsulatum, Paracoccidioides brasiliensis, Sporothrix schenckii, Malassezia sympodialis and Candida albicans. Here we investigated the size, composition, kinetics of internalization by bone marrow‐derived murine macrophages (MO) and dendritic cells (DC), and the immunomodulatory activity of C. albicans EV. We also evaluated the impact of EV on fungal virulence using the Galleria mellonella larvae model. By transmission electron microscopy and dynamic light scattering, we identified two populations ranging from 50 to 100 nm and 350 to 850 nm. Two predominant seroreactive proteins (27 kDa and 37 kDa) and a group of polydispersed mannoproteins were observed in EV by immunoblotting analysis. Proteomic analysis of C. albicans EV revealed proteins related to pathogenesis, cell organization, carbohydrate and lipid metabolism, response to stress, and several other functions. The major lipids detected by thin‐layer chromatography were ergosterol, lanosterol and glucosylceramide. Short exposure of MO to EV resulted in internalization of these vesicles and production of nitric oxide, interleukin (IL)‐12, transforming growth factor‐beta (TGF‐β) and IL‐10. Similarly, EV‐treated DC produced IL‐12p40, IL‐10 and tumour necrosis factor‐alpha. In addition, EV treatment induced the up‐regulation of CD86 and major histocompatibility complex class‐II (MHC‐II). Inoculation of G. mellonella larvae with EV followed by challenge with C. albicans reduced the number of recovered viable yeasts in comparison with infected larvae control. Taken together, our results demonstrate that C. albicans EV were immunologically active and could potentially interfere with the host responses in the setting of invasive candidiasis.  相似文献   
159.
We have developed a full genome virus detection process that combines sensitive nucleic acid preparation optimised for virus identification in fecal material with Illumina MiSeq sequencing and a novel post-sequencing virus identification algorithm. Enriched viral nucleic acid was converted to double-stranded DNA and subjected to Illumina MiSeq sequencing. The resulting short reads were processed with a novel iterative Python algorithm SLIM for the identification of sequences with homology to known viruses. De novo assembly was then used to generate full viral genomes. The sensitivity of this process was demonstrated with a set of fecal samples from HIV-1 infected patients. A quantitative assessment of the mammalian, plant, and bacterial virus content of this compartment was generated and the deep sequencing data were sufficient to assembly 12 complete viral genomes from 6 virus families. The method detected high levels of enteropathic viruses that are normally controlled in healthy adults, but may be involved in the pathogenesis of HIV-1 infection and will provide a powerful tool for virus detection and for analyzing changes in the fecal virome associated with HIV-1 progression and pathogenesis.  相似文献   
160.
We investigated species relationships and timing of speciation in North American Haemorhous finches by using a mitochondrial phylogeographic approach combined with a multilocus species tree reconstruction. Haemorhous purpureus and H. cassinii were strongly supported as sister taxa, and H. mexicanus was sister to H. purpureus + H. cassinii. Our divergence times indicated that diversification within Haemorhous occurred progressively from the Late Miocene into the Pleistocene. Our inferred pattern of speciation demonstrates the complexity of the origins of North American birds, and provides additional evidence that a single cause for speciation in closely related North American birds, such as Late Pleistocene glacial–interglacial cycles, is unlikely.  相似文献   
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