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981.
982.
Zhen Yang Wenjie Jin Zhenpeng Zhao Weidong Lin Di Zhang Enqi Yu Aijian Qin Hanchun Yang 《Archives of virology》2014,159(12):3407-3412
In this study, 396 samples from diarrheic pigs on 46 pig farms in Jiangsu Province, China, were analyzed by RT-PCR. One-hundred eighty-one pigs from 37 farms tested positive for porcine kobuvirus (PKV). Phylogenetic analysis of the 3D gene from 19 isolates showed sequence homology of 88.0 %-100 % and 69.4 %-100 % for nucleotides and amino acids, respectively, while similarity to isolates of other kobuviruses was 69.6 %–78.8 % and 27.8 %–56.9 %, respectively. One-hundred eighty-five samples contained two or more pathogens, and 31/68 PKV-positive samples tested positive for other diarrheic pathogens, confirming the existence of PKV infection and coinfection. 相似文献
983.
Jian Liu Jun Li Xiang Zeng Zhiguo Rao Jianfei Gao Bicheng Zhang Yong Zhao Bo Yang Zhigang Wang Lifang Yu Weixing Wang 《Inflammation》2014,37(3):984-992
In order to understand how tumor cells can escape immune surveillance mechanisms and thus develop antitumor therapies, it is critically important to investigate the mechanisms by which the immune system interacts with the tumor microenvironment. In our current study, wild-type mice were inoculated with melanoma cell line B16-F10 (1?×?106/mouse) and treated with the formyl peptide receptor (FPR) agonist WKYMVm or the FPR antagonist WRW4. Growth of melanoma cell line B16-F10 was significantly inhibited in WKYMVm-treated mice and markedly promoted in WRW4-treated mice compared with control. Decreased number of myeloid-derived suppressor cells (MDSCs) and increased NK cell infiltration in tumor tissues were detected from WKYMVm-treated mice. Next, we showed that depletion of NK cell significantly increased tumor development in B16 tumor-bearing mice compared with the control group, and the suppressed tumor-developing effect of WKYMVm in B16 melanoma was abrogated with NK cell depletion. We also found that WKYMVm stimulates chemotactic migration in NK cells via the FPR family, and this was dependent on extracellular signal-related kinase (ERK) activation. Moreover, in our further experiment, we showed that the increased infiltration of NK cell and promoted NK cell chemotaxis in B16 melanoma induced by WKYMVm were both abolished with ERK inhibitor PD98059 administration. In conclusion, the FPR family promoted NK cell migration through ERK activation and inhibited B16 melanoma growth in a murine model. 相似文献
984.
Xiao Gou Zhen Wang Ning Li Feng Qiu Ze Xu Dawei Yan Shuli Yang Jia Jia Xiaoyan Kong Zehui Wei Shaoxiong Lu Linsheng Lian Changxin Wu Xueyan Wang Guozhi Li Teng Ma Qiang Jiang Xue Zhao Jiaqiang Yang Baohong Liu Dongkai Wei Hong Li Jianfa Yang Yulin Yan Guiying Zhao Xinxing Dong Mingli Li Weidong Deng Jing Leng Chaochun Wei Chuan Wang Huaming Mao Hao Zhang Guohui Ding Yixue Li 《Genome research》2014,24(8):1308-1315
The hypoxic environment imposes severe selective pressure on species living at high altitude. To understand the genetic bases of adaptation to high altitude in dogs, we performed whole-genome sequencing of 60 dogs including five breeds living at continuous altitudes along the Tibetan Plateau from 800 to 5100 m as well as one European breed. More than 150× sequencing coverage for each breed provides us with a comprehensive assessment of the genetic polymorphisms of the dogs, including Tibetan Mastiffs. Comparison of the breeds from different altitudes reveals strong signals of population differentiation at the locus of hypoxia-related genes including endothelial Per-Arnt-Sim (PAS) domain protein 1 (EPAS1) and beta hemoglobin cluster. Notably, four novel nonsynonymous mutations specific to high-altitude dogs are identified at EPAS1, one of which occurred at a quite conserved site in the PAS domain. The association testing between EPAS1 genotypes and blood-related phenotypes on additional high-altitude dogs reveals that the homozygous mutation is associated with decreased blood flow resistance, which may help to improve hemorheologic fitness. Interestingly, EPAS1 was also identified as a selective target in Tibetan highlanders, though no amino acid changes were found. Thus, our results not only indicate parallel evolution of humans and dogs in adaptation to high-altitude hypoxia, but also provide a new opportunity to study the role of EPAS1 in the adaptive processes.The mechanisms of organismal adaptation to high-altitude hypoxia are of great interest during recent years. Highland wild animals have a long life history at high altitude, and the whole genomes of yak (descendants of wild yak) (Qiu et al. 2012), Tibetan antelope (Ge et al. 2013), snow leopard (Cho et al. 2013), and wild boar (Li et al. 2013) have been sequenced. In contrast, the human settlement history on highland is rather short, which dates from ∼25,000 yr ago (Zhao et al. 2009). Whole-genome genotyping and re-sequencing have been performed for three typical highland populations including Tibetans (Beall et al. 2010; Bigham et al. 2010; Simonson et al. 2010; Yi et al. 2010; Peng et al. 2011; Xu et al. 2011), Andeans (Bigham et al. 2009, 2010), and Ethiopians (Alkorta-Aranburu et al. 2012; Scheinfeldt et al. 2012).The increased oxygen uptake and delivery are physiological hallmarks of high-altitude adaptation. On one hand, the capacity of oxygen uptake is determined by hemoglobin concentration and oxygen affinity. For example, the Andean highlanders display a high level of hemoglobin concentration (Beall et al. 2002; Beall 2007). The high oxygen affinity of hemoglobin is found in many highland animals such as yak (Weber et al. 1988), alpaca (Piccinini et al. 1990), deer mice (Storz et al. 2007; Storz et al. 2009), bar-headed goose (Zhang et al. 1996; Liang et al. 2001), and Andean goose (Jessen et al. 1991). On the other hand, the rate of oxygen delivery is determined by blood flow. For example, although Tibetans maintain a nearly normal level of hemoglobin concentration and a low level of oxygen saturation, they display a high level of blood flow, resulting in the increase of oxygen delivery (Beall et al. 2001; Erzurum et al. 2007).Whole-genome scans revealed that positive selection for human high-altitude adaptation occurred in the hypoxia-inducible factor (HIF) pathway (Bigham et al. 2009; Beall et al. 2010; Bigham et al. 2010; Simonson et al. 2010; Yi et al. 2010; Peng et al. 2011; Xu et al. 2011; Alkorta-Aranburu et al. 2012; Scheinfeldt et al. 2012), which regulates genes associated with blood physiology. In addition, metabolic pathways may also be involved in the adaptive process of yak (Qiu et al. 2012) and Tibetan antelope (Ge et al. 2013).Although a lot of studies focused on wildlife and human highlanders, no research was performed on domesticated animals that migrated to the plateau with humans, which represent an adaptation pattern on a short evolutionary time scale of thousands of years. For example, the Tibetan Mastiff is a native dog living in the Tibetan Plateau with an altitude of 3000–6000 m. It is also an ancient dog in the world (Li and Zhang 2012). However, the genetic and physiological mechanisms of its adaptation to high-altitude environments remain elusive.In this study, we sampled five dog breeds including the Tibetan Mastiff from continuous altitudes along the Ancient Tea Horse Road in southwestern China as well as one European breed. We performed whole-genome sequencing for the dogs and identified candidate genes for high-altitude adaptation using selective sweep mapping. We also measured the hematologic and hemorheologic parameters of the dogs and tested the association between the candidate alleles and blood physiology. 相似文献
985.
Yu Rao Yang Qian Yufei Tao Xiao She Yalin Li Zhenming Che Hehe Li Lei Liu 《RSC advances》2019,9(66):38520
The physicochemical and microbial changes, volatile profile, texture and appearance were investigated in three groups of Sichuan pickles differing in oxygen exposure during a 64 day fermentation process. At the beginning, all the Sichuan pickles displayed similar sensory and fermentation characteristics regarding lactic acid bacteria domination, sugar utilization, and lactate accumulation. Soon afterwards, continued exposure allowed premature pellicle formation and typical aerobic deterioration of Sichuan pickle, accompanied by texture destruction and an odorous stench characterized by arenes and aldehydes on the 32nd day. Meanwhile, the facultative anaerobes including Lactobacillus (90 ± 2%), Pediococcus (4.7 ± 0.3%) and Lactococcus (1.2 ± 0.8%) were the dominant genera and probably associated with acetic acid production and arene enrichment under oxygen exposure conditions on the 32nd day. Until the 48th day, intermittent oxygen exposure resulted in pellicle formation and an unpleasant flavor characterized by ketones, esters and S-methyl thioacetate. In comparison, Sichuan pickle without oxygen exposure always maintained a relatively favorable fragrant scent and texture. Besides Lactobacillus, anaerobic genera were the main bacteria in Sichuan pickle under closed conditions and accounted for 50 ± 9% of the total bacteria on the 32nd day. The study indicated the microbial and chemical characteristics of Sichuan pickles during practical production and provided a theoretical guidance for the industrial production of Sichuan pickle.The physicochemical and microbial changes, volatile profile, texture and appearance were investigated in three groups of Sichuan pickles differing in oxygen exposure during a 64 day fermentation process. 相似文献
986.
Background: Monocyte subsets with low CD14 expression that coexpress CD16 (CD14+CD16+) are called non‐classic or hyperinflammatory monocytes. Previous studies have reported an increase in the percentage of CD14+CD16+ monocytes in the peripheral blood of patients with chronic periodontitis (CP). To our knowledge, there are no reports demonstrating the presence of CD14+CD16+ monocyte–derived macrophages (MDMs) in the gingival tissue. The objective of this study is to identify the proportion of non‐classic (CD14+CD16+) monocytes/macrophages in peripheral blood and gingiva of healthy individuals and patients with CP. Methods: A total of 60 individuals (n = 30 per group) were recruited for the study. Group 1 included 30 individuals with healthy gingiva, and group 2 included 30 patients with CP. Direct immunofluorescent staining was done in 200 μL whole‐blood and single‐cell suspensions obtained from gingival tissue, with fluorochrome‐conjugated monoclonal antibodies against CD14, CD16, and human leukocyte antigen‐DR (HLA‐DR), and subjected to flow cytometric analysis. Results: The mean percentage of CD14+CD16+ monocytes in the peripheral blood of healthy individuals was 9.10% ± 1.39%, and for patients with CP it was 14.18% ± 2.69% (P <0.05). The mean percentage of CD14+CD16+ MDMs in the gingival tissue of healthy individuals was found to be 0.93% ± 0.33%, whereas in patients with CP, it was 1.92% ± 0.78% (P <0.01). Non‐classic monocytes/macrophages showed a high median fluorescent intensity for HLA‐DR (DR++). Conclusion: This study demonstrates an increased proportion of CD14+CD16+HLA‐DR++ monocytes/macrophages in the peripheral blood and gingiva of patients with CP. 相似文献
987.
J. K. Dayashankara Rao Neelima Gehlot Vijay Siwach 《Journal of maxillofacial and oral surgery》2014,13(4):488-494
Purpose
The present study was carried out to evaluate the usefulness of mini retromandibular approach on accessibility, scarring and stability in open reduction and internal fixation of sub condylar fractures.Materials and Methods
Fifteen patients underwent open reduction and rigid fixation of middle and low subcondylar fractures, with mini-retro mandibular approach.Results
No signs of infection were observed in any patient postoperatively. Surgical scar was imperceptible and esthetically acceptable in all the cases. Out of 15 patients, only one patient had discrepancy in occlusion and after 2 months satisfactory centric occlusion was achieved. Salivary fistula (parotid fistula) was observed in 3 cases within 1 week postoperatively, which was treated spontaneously with the use of hypertonic saline. Transient facial nerve weakness was observed in 2 patients, in one patient it resolved in 4 weeks postoperatively and in second patient 3 months postoperatively. Mouth opening increased in all the patients with time. Average mouth opening at 1 week interval was 19.6 mm, at 2 months interval 28.2 mm, and after 6 months 38.33 mm suggesting that mouth opening gradually increased with time. At the end of 2 months postoperatively none of the patients had any restriction in lateral movements. At 2 months postoperatively 4 patients had deviation but none of the patients had any deviation 6 months postoperatively.Conclusion
It is evident from the results of our study that open reduction and internal fixation using mini-retromandibular approach is good treatment option in management of mandibular condylar fractures. 相似文献988.
Sen-Lin Xu Dong-Zu Zeng Wei-Guo Dong Yan-Qing Ding Jun Rao Jiang-Jie Duan Qing Liu Jing Yang Na Zhan Ying Liu Qi-Ping Hu Xia Zhang You-Hong Cui Hsiang-Fu Kung Shi-Cang Yu Xiu-Wu Bian 《International journal of clinical and experimental pathology》2014,7(6):2976-2986
Purpose: Aldehyde dehydrogenase 1A1 (ALDH1A1) has been proposed as a candidate biomarker for colorectal carcinoma (CRC). However, the heterogeneity of its expression makes it difficult to predict the outcome of CRC. The aim of this study was to evaluate the diagnostic and prognostic value of this molecule in CRC. Methods and Results: In this study, we examined ALDH1A1 expression by immunohistochemistry including 406 cases of primary CRC with corresponding adjacent mucosa, with confirmation of real-time PCR and Western blotting. We found that the expression patterns of ALDH1A1 were heterogeneous in the CRC and corresponding adjacent tissues. We defined the ratio of ALDH1A1 level in adjacent mucosa to that in tumor tissues as RA/C and found that the capabilities of tumor invasion and metastasis in the tumors with RA/C < 1 were significantly higher than those with RA/C ≥ 1. Follow-up data showed the worse prognoses in the CRC patients with RA/C < 1. For understanding the underlying mechanism, the localization of β-catenin was detected in the CRC tissues with different patterns of ALDH1A1 expression from 221 patients and β-catenin was found preferentially expressed in cell nuclei of the tumors with RA/C < 1 and ALDH1A1high expression of HT29 cell line, indicating that nuclear translocation of β-catenin might contribute to the increased potentials of invasion and metastasis. Conclusion: Our results indicate that RA/C is a novel biomarker to reflect the distinct expression patterns of ALDH1A1 for predicting metastasis and prognosis of CRC. 相似文献
989.
Qiu Rao Qiu-Yuan Xia Qin Shen Shan-Shan Shi Pin Tu Qun-Li Shi Xiao-Jun Zhou 《International journal of clinical and experimental pathology》2014,7(4):1782-1787
In this study, we analyzed the immunohistochemical and molecular profiles of an unusual RCC showed coexistent absence of INI1 and BRG1 expression, rhabdoid morphology, and poor prognosis. Histologically, the tumor had rhabdoid features, which were demonstrated by large round to polygonal cells with eccentric nuclei, prominent nucleoli, and eosinophilic cytoplasm varying from abundant to scanty. Immunohistochemically, the tumor were positive for BRM, PBRM1, ARID1A, CD10, CKpan, Vimentin, carbonic anhydrase IX (CA-IX), and P504S (AMACR) but negative for INI1, BRG1, HMB45, melan A, CK7, CD117, Ksp-cadherin, TFEB, TFE3, and Cathepsin K. We detected all three exons status of the VHL gene of the tumor and observed 1 somatic mutations in 1st exon. Chromosome 3p deletion, coupled with polysomy of chromosome 3 was also found. Based on these findings, it is further indicated that in some cases, rhabdoid RCC may arise from clear cell RCC. SWI/SNF chromatin remodeling complex may be an attractive candidate for being the “second hit” in RCCs and may play an important role during tumor progression. The role of SWI/SNF complex in rhabdoid RCC should be further studied on a larger number of cases. 相似文献
990.
Manu Tomar Raghavendra Prahlad Rao Palaniyamma Dorairaj Abhishek Koshta Sowbhagya Suresh Mohamed Rafiq Rajesh Kumawat Rangesh Paramesh Babu U. V K.
V. Venkatesh 《RSC advances》2019,9(32):18578
Hydroxycitric acid (HCA), a major active ingredient of Garcinia cambogia extracts, is known to suppress body weight gain and fat synthesis in animals and humans. But the underlying mechanism of HCA action is not fully understood. Clinical study on 100 obese individuals for a period of 3 months was performed followed by a computational study aimed to investigate the effects of HCA treatment on human subjects at anthropometric and plasma lipid profile levels. A detailed hepatic metabolic model was used to incorporate the effect of HCA at the metabolic pathway level. Perturbation analysis of ATP citrate lyase activity in the metabolic pathway was performed to simulate the net effect of HCA. Significant reductions in body weight, triceps, subscapular, and mid axillary measurements as well as in serum triglyceride, cholesterol, HDL and LDL levels were observed following HCA dosage. During the study, half of the subjects experienced a decline in body weight and the remainder experienced an increase in body weight. However, analysis of fat mass with the help of empirical correlations clearly showed significant reduction in the mean values due to HCA dosage in both cases. An extra increase in fat free mass was responsible for offsetting the decrease in fat mass for the subjects who experienced an increase in body weight during the trials. Perturbation analysis showed a net reduction in fatty acid, triglyceride and cholesterol synthesis along with urea cycle fluxes under lipogenetic conditions. Moreover, protein synthesis fluxes increased under these conditions. These results indicate that HCA treatment can reduce body weight gain and fat accumulation in obese subjects along with improving their anthropometric parameters and metabolic state.Hydroxycitric acid (HCA), a major active ingredient of Garcinia cambogia extracts, is known to suppress body weight gain and fat synthesis in animals and humans. 相似文献