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91.
Lung cancer is a leading cause of cancer‐related deaths with an increasing incidence and poor prognoses. To further understand the regulatory mechanisms of lipidomic profiles in lung cancer subtypes, we measure the profiles of plasma lipidome between health and patients with lung cancer or among patients with squamous cell carcinomas, adenocarcinoma or small cell lung cancer and to correct lipidomic and genomic profiles of lipid‐associated enzymes and proteins by integrating the data of large‐scale genome screening. Our studies demonstrated that circulating levels of PS and lysoPS significantly increased, while lysoPE and PE decreased in patients with lung cancer. Our data indicate that lung cancer‐specific and subtype‐specific lipidomics in the circulation are important to understand mechanisms of systemic metabolisms and identify diagnostic biomarkers and therapeutic targets. The carbon atoms, dual bonds or isomerism in the lipid molecule may play important roles in lung cancer cell differentiations and development. This is the first try to integrate lipidomic data with lipid protein‐associated genomic expression among lung cancer subtypes as the part of clinical trans‐omics. We found that a large number of lipid protein‐associated genes significantly change among cancer subtypes, with correlations with altered species and spatial structures of lipid metabolites.  相似文献   
92.

Background

Candidemia is one of the most common nosocomial bloodstream infections. Early diagnosis and antifungal treatment improve clinical outcomes in some studies but not all, with diverse data reported from different institutions. Similarly, antifungal resistance is more common in the USA than in Europe, but there is little data regarding the microbiology and clinical course of candidemia in adult patients in Asia.

Aims

(1) To capture species distribution and drug resistance rates among Candida bloodstream isolates, (2) to describe clinical features of candidemia, and (3) to identify factors associated with all-cause mortality, with emphasis on early initiation of antifungal treatment, at a large tertiary University Hospital in China.

Methods

In this single-center retrospective study, we identified all patients with candidemia, between 2008 and 2014. Demographic and clinical characteristics, microbiological information, details of antifungal therapy and clinical outcomes were collected.

Results

We studied 166 patients. 71 (42.8%) had cancer. Candida albicans was the most frequent species (37.3%), followed by C. parapsilosis (24.1%), C. tropicalis (22.8%), and C. glabrata (14.5%). Antifungal resistance was more frequent in non-albicans strains and especially C. glabrata. Twenty patients received inappropriate treatment with all-cause mortality of 35%. The remaining 146 patients had significantly lower mortality (21.9%, P?=?0.045). Among patients who received antifungal treatment, mortality rate increased with time to appropriate antifungal therapy (AAT): 13.7%, for?<?24 h, 21.1% for 24–48 h, 23.1% for?>?48 h, and 32.4% among patients who received no AT (χ2 for trend P?=?0.039). Initiating AAT more than 24 h after blood culture collection was an independent risk factor for mortality, after adjustment for other confounders (OR 7.1, 95% CI 1.3–39.4, P?=?0.024).

Conclusions

Candida albicans was the most frequent cause of candidemia at a large tertiary hospital in China, but antifungal resistance is a growing concern among non-albicans Candida species. The mortality rate of patients treated with ineffective antifungal agents based on in vitro susceptibilities was similar to that of patients who received no treatment at all, and delayed initiation of antifungal treatment was associated with increased risk of death.
  相似文献   
93.
Remote alpine regions were considered to be largely unimpacted by anthropogenic disturbance, but it is now clear these areas are changing rapidly. It is often difficult to identify the causal processes underpinning ecological change because the main drivers (direct and indirect climate forcing, land use change and atmospheric deposition) are acting simultaneously. In addition, alpine landscapes are morphometrically complex with strong local environmental gradients creating natural heterogeneity which acts as a variable filter to climate and anthropogenic forcing, emphasizing the need for analyzing responses at multiple sites. The eastern margin of Tibet is a hotspot of global biodiversity and is affected by both atmospheric N and dust deposition, whereas regional climate warming is comparatively recent. Here we use 210Pb and 137Cs dated sediment records from nine alpine lakes, and statistical measures of diatom ecological change (turnover and PCA axis 1 scores) to determine regional scale patterns in community response to global environmental change forcing over approximately the last 150 years. The study lakes showed contrasting ecological responses with increased nutrient input as the primary driver of change, mediated by lake morphology and catchment characteristics. Turnover rates of diatom composition, although low, are significantly associated with lake volume, lake area, altitude and DOC.  相似文献   
94.
95.
Lung cancer is one of the most common malignancies worldwide. Actinidia chinensis Planch root extract (acRoots) was found to have the capacity of the anti-tumor, although the molecular mechanisms remain unclear. The present study aims to investigate the molecular mechanisms by which lung cancer cells sense to inhibitory effects of acRoots with a special focus on immune-associated gene profiles. We firstly provide a preclinical evidence that acRoots can significantly inhibit lung cancer cell proliferation and apoptosis via the PI3K-OASL signal pathway. The heterogeneous alterations of immune-associated gene profiles of lung cancer cell types were measured after treatment with various doses of acRoots. The OASL gene was identified as the key regulator in molecular networks of acRoots-treated lung cancer cells and validated. The OASL gene plays an important role in the regulation of lung cancer cell sensitivity to acRoots, which modulated by the PI3K signal pathway. Thus, our data indicate that OASL can be one of the decisive regulators to maintain lung cancer cell susceptibility to acRoots and may be associated with the development of drug resistance. The regulation of OASL can be an alternative strategy to improve drug efficacy during cancer therapies.  相似文献   
96.
Zinc (Zn) is an essential trace element that is required during mammalian developmental processes. The objective of this study was to investigate the effects of Zn supplementation during in vitro maturation (IVM) on the developmental capacity of yak (Bos grunniens) oocytes. Cumulus expansion, nuclear maturation, intracellular glutathione (GSH), reactive oxygen species (ROS) levels, superoxide dismutase (SOD) activity, subsequent embryonic development, and the expression of Zn transporters (ZnTs) and Zrt and Irt-like proteins (ZiPs) were evaluated. The Zn concentrations in yak plasma and follicular fluid were 0.740?±?0.012 and 0.382?±?0.009 μg/mL, respectively. The cumulus expansion did not show significant differences in COCs after matured with or without Zn supplementation (P?>?0.05). The intracellular GSH was higher in oocytes matured with 1 or 2 mg/L Zn than in control group (0 mg/L) (P?<?0.05). However, ROS levels of oocytes matured with 1 or 2 mg/L Zn were reduced significantly compared with the control and 0.5 mg/L groups (P?<?0.05). The SOD activity was increased significantly after Zn supplementation. The cleavage rate was not significantly different after Zn supplementation (P?>?0.05). Percentages of matured oocytes that developed into the blastocyst stage after IVF were 47.9, 50.5, 60.4, and 58.9% for 0, 0.5, 1, and 2 mg/L Zn groups, respectively. Gene expression analysis revealed that the expression patterns associated with Zn were changed after Zn supplementation. In conclusion, Zn supplementation to IVM improved yak oocyte maturation and subsequent development by increasing GSH and SOD activity, decreasing ROS in oocytes.  相似文献   
97.
采用硫酸铵沉淀及柱层析等步骤纯化了日本根霉IFO5318的β—葡萄糖苷酶,回收率为22%。该酶分子量约为4.0×10~5,由四个相同大小的亚基组成;最适反应温度55℃,最适反应pH5.5;对热较敏感,但能在较大的pH范围内保持稳定。用对硝基苯基—β-D-吡喃葡糖苷为底物,测得的K_m和V_(max)值分别为0.825mg·ml~(-1)和135.4μmol·min~(-1)·mg~(-1)。该酶对纤维二糖的水解能力最强,SDS、Fe~(3 )、Hg~2 )等对酶活力有抑制作用。  相似文献   
98.
We detected the expression of IL-12 p40/p35 mRNA by semi-quantitative RT-PCR and silver staining, and studied the molecular interaction between the IL-12 expression and the NF-kB activation induced by LPS and IFN-γ/LPS in murine peritoneal suppressor macrophages (MPSMs). It was found that IFN-γ strongly enhanced the LPS-induced IL-12 p40 and p35 mRNA expression. Both p40 and p35 mRNA levels were approximately equal. IFN-γ also greatly promoted the LPS-induced secretion of IL-12 p70 in MPSMs. The Proteasome Inhibitor I (PSI) could block the expres-sion of IL-12 p40 and p35 mRNA, and the degradation of IkBα induced by LPS or LPS/IFN-γ. EM-SA showed that LPS could augment the NF-kB binding activity to p40 promoter DNA. However, IFN-γ could neither enhance the LPS-induced NF-kB activity nor promote the degradation of IkBα. Taken together, the data suggest: (i) IFN-γ/LPS could strongly induce the expression of IL-12 p40 and p35 mRNA; both the expression levels were equal; this phenomenon coincided with the high-level secretion of IL-12 p70 induced by IFN-γ/LPS; (ii) NF-kB signal pathway is essential for IFN-γ/LPS to induce IL-12 mRNA expression; (iii) by blocking the degradation of IkB, the PSI sup-presses the IL-12 p40/p35 mRNA expression induced by LPS and IFN-γ/LPS; (iv) NF-kB signal may not be involved in the mechanism by which IFN-γ enhanced the expression of the LPS-induced IL-12 p40/p35 mRNA.  相似文献   
99.
Up to date, the scarcity of publicly available complete mitochondrial sequences for European wild pigs hampers deeper understanding about the genetic changes following domestication. Here, we have assembled 26 de novo mtDNA sequences of European wild boars from next generation sequencing (NGS) data and downloaded 174 complete mtDNA sequences to assess the genetic relationship, nucleotide diversity, and selection. The Bayesian consensus tree reveals the clear divergence between the European and Asian clade and a very small portion (10 out of 200 samples) of maternal introgression. The overall nucleotides diversities of the mtDNA sequences have been reduced following domestication. Interestingly, the selection efficiencies in both European and Asian domestic pigs are reduced, probably caused by changes in both selection constraints and maternal population size following domestication. This study suggests that de novo assembled mitogenomes can be a great boon to uncover the genetic turnover following domestication. Further investigation is warranted to include more samples from the ever-increasing amounts of NGS data to help us to better understand the process of domestication.  相似文献   
100.
Neuropathic pain, caused by a lesion or dysfunction of the somatosensory nervous system, is a severe debilitating condition with which clinical treatment remains challenging. Jun activation domain-binding protein (JAB1) is a multifunctional protein that participates in several signaling pathways, controlling cell proliferation and apoptosis. However, the expression and possible function of JAB1 in the pathogenesis of neuropathic pain has not been elucidated. This study aimed to investigate the possible involvement of JAB1. Here, employing a neuropathic pain model induced by chronic constriction injury (CCI) on rats, we reported the role of JAB1 in the maintenance of neuropathic pain. By western blot, we found that CCI markedly up-regulated JAB1 expression in the dorsal root ganglion (DRG) and spinal cord. Immunofluorescent assay demonstrated that JAB1 was extensively localized in IB4-, CGRP- and NF200-positive neurons in the injured L5 DRG, and mainly co-localized with NeuN in spinal cord. In addition, we showed that CCI induced phosphorylation of p65 and JNK in vivo. Intrathecal injection of JAB1 siRNA significantly attenuated the CCI-induced JNK and p65 phosphorylation and alleviated both mechanical allodynia and heat hyperalgesia in rats. Taken together, these results suggested that JAB1 promotes neuropathic pain via positively regulating JNK and NF-κB activation.  相似文献   
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