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The use of bioactive peptides as a doping agent in both human and animal sports has become increasingly popular in recent years. As such, methods to control the misuse of bioactive peptides in equine sports have received attention. This paper describes a sensitive accurate mass method for the detection of 40 bioactive peptides and two non‐peptide growth hormone secretagogues (< 2 kDa) at low pg/mL levels in horse urine using ultra‐high performance liquid chromatography‐high resolution mass spectrometry (UHPLC/HRMS). A simple mixed‐mode cation exchange solid‐phase extraction (SPE) cartridge was employed for the extraction of 42 targets and/or their in vitro metabolites from horse urine. The final extract was analyzed using UHPLC/HRMS in positive electrospray ionization (ESI) mode under both full scan and data independent acquisition (DIA, for MS2). The estimated limits of detection (LoD) for most of the targets could reach down to 10 pg/mL in horse urine. This method was validated for qualitative detection purposes. The validation data, including method specificity, method sensitivity, extraction recovery, method precision, and matrix effect were reported. A thorough in vitro study was also performed on four gonadotrophin‐releasing factors (GnRHs), namely leuprorelin, buserelin, goserelin, and nafarelin, using the S9 fraction isolated from horse liver. The identified in vitro metabolites have been incorporated into the method for controlling the misuse of GnRHs. The applicability of this method was demonstrated by the identification of leuprorelin and one of its metabolites, Leu M4, in urine obtained after intramuscular administration of leuprorelin to a thoroughbred gelding (castrated horse).  相似文献   
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BackgroundValues of fractional flow reserve (FFRCT) by coronary computed tomography angiography (CTA) decline from the ostium to the terminal vessel, irrespective of stenosis severity. The purpose of this study is to determine if the site of measurement of FFRCT impacts assessment of ischemia and its diagnostic performance relative to invasive FFR (FFRINV).Methods1484 patients underwent FFRCT; 1910 vessels were stratified by stenosis severity (normal; <25%, 25–50%, 50–70%, and >70% stenosis). The rates of positive FFRCT (≤0.8) were determined by measuring FFRCT from the terminal vessel and from distal-to-the-lesion. Reclassification rates from positive to negative FFRCT were calculated. Diagnostic performance of FFRCT relative to FFRINV was evaluated in 182 vessels using linear regression, Bland Altman analysis, and receiver operating characteristic (ROC) curves.ResultsPositive FFRCT was identified in 24.9% of vessels using terminal vessel FFRCT and 10.1% using FFRCT distal-to-the-lesion (p ?< ?0.001). FFRCT obtained distal-to-the-lesion resulted in reclassification of 59.6% of positive terminal FFRCT to negative FFRCT. Relative to FFRINV, there were improvements in specificity (50% to 86%, p ?< ?0.001), diagnostic accuracy (65% to 88%, p ?< ?0.001), positive predictive value (50% to 78%, p ?< ?0.001), and area-under-the-curve (AUC, 0.83 to 0.91, p ?< ?0.001) when FFRCT was measured distal-to-the-lesion.ConclusionFFRCT values from the terminal vessel should not be used to assess lesion-specific ischemia due to high rates of false positive results. FFRCT measured distal-to-the-lesion improves the diagnostic performance of FFRCT relative to FFRINV, ensures that FFRCT values are due to lesion-specific ischemia, and could reduce the rate of unnecessary invasive procedures.  相似文献   
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Idiopathic nephrotic syndrome (INS) is a multifactorial disease, characterized by proteinuria, hypoalbuminemia, edema and hyperlipidemia. Studies in humans and animal models have associated INS with changes in the immune response. The purpose of this article is to review clinical and experimental findings showing the involvement of the immune response in the pathogenesis of INS. The role of the immune system in INS has been shown by clinical and experimental studies. However, the pattern of immune response in patients with INS is still not clearly defined. Many studies show changes in the dynamics of T lymphocytes, especially the regulatory T cells. Alternatively, there are other reports regarding the involvement of the complement system and B lymphocytes in the pathophysiology of INS. Indeed, none of the immunological biomarkers evaluated were undeniably linked to changes in glomerular permeability and proteinuria. On the other hand, some studies suggest a link between urinary chemokines, such as IL-8/CXCL8 and MCP-1/CCL2, and changes in glomerular permeability and/or the deterioration of glomerulopathies. To understand the pathophysiology of INS, longitudinal studies are clearly needed. The characterization of the profile of the immune response might help the development of specific and individualized therapies, leading to clinical improvement and better prognosis.  相似文献   
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Interleukin-15 (IL-15) enhances the effector mechanisms of anti-HIV immune responses and thus is considered a potential adjuvant of HIV-1 vaccine. However, there are a lack of data concerning the relationships between IL-15 expression and regulation in HIV-1-infected patients and the course of disease progression. We found that IL-15, but not IL-15Rα, is expressed at significantly higher levels in the CD14(+) monocytes [stimulated or not with interferon (IFN)-γ] of long-term nonprogressors (LTNP) than in those of HIV-1 progressors or healthy controls. There was no between-group difference in the amounts of soluble IL-15 released from the cells. We also found that like the healthy controls, the LTNP expressed the IL-15 and IL-15Rα genes in a more coordinated manner than the progressors. Our findings show that there are significant differences in IL-15 expression between patients with different courses of HIV infection, and that the coordinated expression of the IL-15 and IL-15Rα genes is dysregulated in patients with progressive disease. They also provide important information concerning the mechanisms of infection and the potential use of IL-15 as a therapeutic agent.  相似文献   
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Purpose

John Cunningham (JC) viral DNA sequence has seldom been reported in patients with brain tumors such as high grade gliomas and medulloblastomas, pointing to a role in the etiopathogenesis of such tumors.

Results

We present a unique clinical case of an HIV-positive pediatric patient with multifocal leukoencephalopathy and confirmed JC virus (JCV) infection that developed a giant-cell glioblastoma.

Conclusions

Experimental data with infected primates has previously hypothesized an association of human giant-cell glioblastoma with JCV or progressive multifocal leukoencephalopathy, though such association has not been documented in the literature for humans. Future studies with larger cohorts and molecular pathological analyses are still needed to corroborate the role of the widely spread human neurotropic virus in early transformation and in the development of brain tumors with different histology in the setting of HIV-related severe immunosuppression.  相似文献   
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Mowat–Wilson syndrome (MWS) is a rare genetic condition where variable and multiple congenital anomalies including Hirschsprung's disease, intellectual disability, and prominent facial features are present. At molecular level, MWS is characterized by many different described mutations in the zinc finger E-box protein 2 (ZEB2) gene, ultimately leading to loss of gene function. This report is the first to describe the association of MWS with two different asynchronous malignant brain tumors (medulloblastoma and glioblastoma) occurring in a child.  相似文献   
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