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《Vaccine》2022,40(16):2370-2378
Porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae (M. hyopneumoniae, Mhp) are two of the most common pathogens involved in the porcine respiratory disease complex (PRDC) resulting in significant economic losses worldwide. Vaccination is the most effective approach to disease prevention. Since PRRSV and Mhp co-infections are very common, an efficient dual vaccine against these pathogens is required for the global swine industry. Compared with traditional vaccines, multi-epitope vaccines have several advantages, they are comparatively easy to produce and construct, are chemically stable, and do not have an infectious potential. In this study, to develop a safe and effective vaccine, B cell and T cell epitopes of PRRSV-GP5, PRRSV-M, Mhp-P46, and Mhp-P65 protein had been screened to construct a recombinant epitope protein rEP-PM that has good hydrophilicity, strong antigenicity, and high surface accessibility, and each epitope is independent and complete. After immunization in mice, rEP-PM could induce the production of high levels of antibodies, and it had good immunoreactivity with anti-rEP-PM, anti-PRRSV, and anti-Mhp antibodies. The anti-rEP-PM antibody specifically recognizes proteins from PRRSV and Mhp. Moreover, rEP-PM induced a Th1-dominant cellular immune response in mice. Our results showed that the rEP-PM protein could be a potential candidate for the development of a safe and effective multi-epitope peptide combined vaccine to control PRRSV and Mhp infections.  相似文献   
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《Pancreatology》2022,22(8):1175-1180
BackgroundHepatic steatosis has been described as a common finding in adults following total pancreatectomy with islet autotransplantation (TPIAT) but it is unknown if this occurs in children and adolescents.ObjectivesTo define the frequency of post-TPIAT hepatic steatosis in a sample of children and adolescents and to identify clinical predictors of incident steatosis post-TPIAT.MethodsIn this prospective study, consecutive participants at least 1-month post-TPIAT underwent a liver MRI with proton density fat fraction (PDFF) and blood draw at our pediatric academic medical center between April 2021 and January 2022. Comparison clinical pre-TPIAT liver MRI or ultrasound and insulin use and graft function data were extracted from the medical record. T-tests were used for the comparison of means across continuous variables between participants with and without post-TPIAT steatosis.ResultsA total of 20 participants (mean: 13 ± 4 years; 12 female) were evaluated. Mean liver PDFF at research MRI was 7.4 ± 6.2% (range: 2–25%). Seven participants (35%) had categorical hepatic steatosis (PDFF>5%) post-TPIAT, five of whom had pre-TPIAT steatosis, reflecting a 13% (2/15; 95% CI: 2–40%) incidence of post-TPIAT steatosis. Participant characteristics were not significantly different between subgroups with and without post-TPIAT steatosis. Mean PDFF at research MRI was not different between graft function subgroups (7.5% optimal/good vs. 7.3% marginal/failure; p = .96).ConclusionOur study shows a moderate prevalence but low incidence of hepatic steatosis in a small sample of children and adolescents post-TPIAT. This study raises questions about a causal relationship between TPIAT and hepatic steatosis.  相似文献   
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MicroRNAs (miRNAs) play important roles in prostate cancer development. However, it remains unclear how individual miRNAs contribute to the initiation and progression of prostate cancer. Here we show that a basal layer‐enriched miRNA is required for prostate tumorigenesis. We identify miR‐205 as the most highly expressed miRNA and enriched in the basal cells of the prostate. Although miR‐205 is not required for normal prostate development and homeostasis, genetic deletion of miR‐205 in a Pten null tumor model significantly compromises tumor progression and does not promote metastasis. In Pten null basal cells, loss of miR‐205 attenuates pAkt levels and promotes cellular senescence. Furthermore, although overexpression of miR‐205 in prostate cancer cells with luminal phenotypes inhibits cell growth in both human and mouse, miR‐205 has a minimal effect on the growth of a normal human prostate cell line. Taken together, we have provided genetic evidence for a requirement of miR‐205 in the progression of Pten null‐induced prostate cancer.  相似文献   
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This study is focussed on micro-encapsulation of essential oils in polylactic acid (PLA) and a poly(methyl methacrylate) (PMMA) matrix as well as blends of the same. Microspheres were prepared by the solvent evaporation technique and characterised by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infra-red spectroscopy (FTIR). The encapsulation efficiencies and release profiles of the essential oils were studied by gas chromatography mass spectrometry (GC-MS) and head-space solid-phase microextraction GC-MS, respectively. Furthermore, the microspheres were tested for antibacterial activity against both Gram-negative and Gram-positive bacterial strains.

The results showed that the microspheres compositions (PLA/PMMA ratio) have significant effect on their characteristics. The process adopted for preparing the microspheres promoted formation of spherical particles at the sizes of 1.5–9.5?µm. The highest encapsulation efficiency of the prepared microspheres was observed in systems consisting of linalool (81.10?±?10.0?wt. % for PLA system and 76.0?±?3.3?wt. % for PMMA system). Confirmation was also made that the release rate of the microspheres was affected by the size of the same.  相似文献   

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