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931.
目的 探讨应用多烯磷脂酰胆碱联合双环醇治疗胃癌化疗所致的药物性肝损伤(DILI)患者疗效及其对血清细胞因子和氧化应激指标的影响。方法 2017年5月~2019年5月我院收治的胃癌根治术后患者78例,给予奥沙利铂、多西他赛和氟尿嘧啶化疗。在化疗过程中出现DILI患者40例,被随机分为对照组(n=19)和观察组(n=21),给予对照组患者多烯磷脂酰胆碱治疗,给予观察组多烯磷脂酰胆碱联合双环醇片治疗,两组均观察4周。采用ELISA法检测血清肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6),采用硫代巴比妥酸法检测血清丙二醛(MDA),采用黄嘌呤氧化法检测血清超氧化物歧化酶(SOD)。采用卡氏功能状态(KPS)量表评估患者生存质量。结果 在治疗4周末,观察组血清丙氨酸氨基转移酶(ALT)水平为(33.5±7.9)U/L,显著低于对照组【(42.4±8.8)U/L,P<0.05】,血清天冬氨酸氨基转移酶(AST)水平为(34.4±5.7)U/L,显著低于对照组【(39.4±6.2)U/L,P<0.05】,血清碱性磷酸酶(ALP)水平为(60.6±14.2)U/L,显著低于对照组【(75.3±16.6)U/L,P<0.05】,而KPS评分为(64.1±17.2)分,显著高于对照组【(48.3±14.5)分,P<0.05】;联合组肝功能复常率为81.0%,显著高于对照组的63.2%(P<0.05);观察组血清TNF-α水平为(15.2±2.1)mg/L,显著低于对照组【(21.4±3.6)mg/L,P<0.05】,血清IL-6水平为(28.1±4.5)pg/mL,显著低于对照组【(46.2±5.9)pg/mL,P<0.05】;血清MDA水平为(5.1±0.8)nmol/mL,显著低于对照组【(5.9±0.7)nmol/mL,P<0.05】,而血清SOD水平为(2.3±0.5)U/mL,显著高于对照组【(1.8±0.4)U/mL,P<0.05】。结论 联合应用多烯磷脂酰胆碱和双环醇片治疗化疗药导致的DILI患者能改善肝功能,可能与抑制了氧化应激反应,降低了血清细胞因子水平有关,值得进一步研究。  相似文献   
932.
Background/AimsThis study aimed to analyze the data of 24 cases of multiple perforation or obstruction of the digestive tract caused by accidental ingestion of magnetic beads, to improve the understanding of its harmfulness to children and explore the best treatment.Materials and MethodsIn total, 24 cases were collected and retrospectively analyzed. These patients were divided into two groups: perforation group and non-perforation group. The medical history, number of magnetic beads, white blood cell (WBC) count, and C-reactive protein (CRP) were analyzed.ResultsThere was no significant difference in age, gender, medical history, number of magnetic beads, and WBC count between the perforation group and non-perforation group, but there was a significant difference in CRP. After the diagnosis, 70% of the cases underwent laparotomy and perforation repair. All cases recovered smoothly after the operation, and no complications occurred during the follow-up.ConclusionThis study offers diagnosis and treatment methods for the perforation or obstruction of the digestive tract caused by accidental ingestion of magnetic beads and raises the awareness regarding the harmfulness of the presence of foreign bodies in the digestive tract.  相似文献   
933.
In spring 2013, a novel avian‐origin influenza A (H7N9) virus emerged in mainland China. The burden of H7N9 infection was estimated based on systematic review and meta‐analysis. The systematic search for available literature was conducted using Chinese and English databases. We calculated the pooled seroprevalence of H7N9 infection and its 95% confidence interval by using Freeman‐Tukey double arcsine transformation. Out of 16 890 records found using Chinese and English databases, 54 articles were included in the meta‐analysis. These included studies of a total of 64 107 individuals. The pooled seroprevalence of H7N9 infection among humans was 0.122% (95% CI: 0.023, 0.275). In high‐risk populations, the highest pooled seroprevalence was observed among close contacts (1.075%, 95% CI: 0.000, 4.357). The seroprevalence among general population was (0.077%, 95% CI: 0.011, 0.180). Our study discovered that asymptomatic infection of H7N9 virus did occur, even if the seroprevalence among humans was low.  相似文献   
934.
935.
BACKGROUNDHepatitis E virus (HEV) superinfection is a suspected promoting factor for hepatocellular carcinoma (HCC) in patients with chronic hepatitis and cirrhosis. However, to date, very few cases of HEV-related HCC have been reported. Nevertheless, the role of HEV re-infection in cirrhotic liver without other chronic hepatitis infections has rarely been explored.CASE SUMMARYA 53-year-old male farmer was diagnosed with liver cirrhosis and splenomegaly in August 2016, accompanied with negative HEV-IgM and positive HEV-IgG. No evidence of hepatitis B virus or hepatitis C virus infection was found. Since then the patient was evaluated for liver function and viral parameters every 3 mo. In June 2017, the patient presented severe fatigue with whole body itching and was diagnosed with HCC. Afterwards this patient experienced quick HCC development, progression, relapse, and metastasis in the following 8 mo, and presented persistent dual positivity of HEV-IgM and HEV-IgG. This patient had a long history of smoking and alcohol consumption.CONCLUSIONThis unique case invokes the importance of HEV surveillance and treatment among cirrhotic patients, HCC cases, and blood donors.  相似文献   
936.
Sixty-two strains of avian infectious bronchitis virus (IBV) were isolated from diseased chickens at different farms in southern China during 2011–2012, and 66.1 % of the isolated strains were associated with typical nephritis. Analysis of the S1 gene sequences amplified from the 62 isolated strains together with 40 reference strains published in Genbank showed nucleotide homologies ranging from 63.5 to 99.9 % and amino acid homologies ranging from 57.9 to 100 %. Phylogenetic analysis revealed that all Chinese IBV strains were clustered into six distinct genetic groups (I–VI). Most of the isolated strains belonged to group I, and the isolation of group V strains was increased compared with an earlier period of surveillance. Current vaccine strains used in China (H120, H52, W93, and Ma5) formed the group Mass which is evolutionarily distant from Chinese isolates. Alignment of S1 amino acid sequences revealed polymorphic and diverse substitutions, insertions, and deletions, and the S1 protein of major pandemic strains contained 540 amino acids with a cleavage site sequence of HRRRR or RRF(L/S)RR. Further analysis showed that recombination events formed a new subgroup. Taken together, these findings suggest that various IBV variants were co-circulating and undergoing genetic evolution in southern China during the observation period. Therefore, long-term continuing surveillance is significantly important for prevention and control of IBV infection.  相似文献   
937.
The mesenteric lymph node (MLN) is the main draining lymph node in mouse enterocoelia, which contains many types of immune cells. Among these cells, natural killer (NK) and natural killer T (NKT) cells belong to innate lymphoid cells (ILCs), which have potent activities for controlling a variety of pathogenic infections. In this study, C57BL/6 mice were infected with Schistosoma japonicum for 5–7 weeks. Lymphocytes were isolated from the MLN to detect changes in the phenotype and function of NK and NKT cells using a fluorescence activating cell sorter (FACS). These results demonstrated that a S. japonicum infection could significantly increase the percentage of NK cells in the mouse MLN, (P?<?0.05). We found an increase in the cell number of both NK and NKT cells. In addition, we found that NK and NKT cells from infected mice expressed higher levels of CD69 compared to normal mice (P?<?0.05). These results demonstrated that a S. japonicum infection could induce MLN NK and NKT cell activation. Moreover, we found that the expression of CD4 was increased in infected MLN NK cells (P?<?0.05). Furthermore, intracellular cytokine staining revealed that expression of IL-4 and IL-17 were significantly enhanced in both the NK and NKT cells of infected mice after phorbol 12-myristate 13-acetate (PMA) and ionomycin stimulation (P?<?0.05). Taken together, these results indicated that infection-induced MLN NK and NKT cells might play roles in modulating the classical T cell response. Finally, our results indicated that the expression of CD94 was decreased in NK cells, suggesting that the downregulation of CD94 expression might served as a mechanism in NK cell activation.  相似文献   
938.
Many Gram-negative bacteria utilize a type III secretion system (T3SS) to translocate virulence proteins into host cells to cause diseases. In responding to infection, macrophages detect some of the translocated proteins to activate caspase-1-mediated cell death, called pyroptosis, and secretion of proinflammatory cytokines to control the infection. Edwardsiella tarda is a Gram-negative enteric pathogen that causes hemorrhagic septicemia in fish and both gastrointestinal and extraintestinal infections in humans. In this study, we report that the T3SS of E. tarda facilitates its survival and replication in murine bone marrow-derived macrophages, and E. tarda infection triggers pyroptosis of infected macrophages from mice and fish and increased secretion of the cytokine interleukin 1β in a T3SS-dependent manner. Deletion of the flagellin gene fliC of E. tarda results in decreased cytotoxicity for infected macrophages and does not attenuate its virulence in a fish model of infection, whereas upregulated expression of FliC in the fliC mutant strain reduces its virulence. We propose that the host controls E. tarda infection partially by detecting FliC translocated by the T3SS, whereas the bacteria downregulate the expression of FliC to evade innate immunity.  相似文献   
939.
Human bocavirus (HBoV), a recently identified pathogen with a worldwide distribution is closely related to paediatric acute respiratory infection and gastroenteritis. The present study was performed to evaluate the immunogenicity of HBoV1 and HBoV2 virus‐like particles (VLPs) as vaccine candidates in mice. Both HBoV1 and HBoV2 VLPs were expressed in the bacmid virus–SF9 cell system. Mice were inoculated three times at 3‐week intervals with HBoV VLPs at one dose intramuscular (i.m.) or intradermal (i.d.) with or without the addition of the alum adjuvant. ELISA was used to detected antibody, and ELISPOT was used to test cellular immune responses. HBoV‐specific IgG antibodies were induced and alum adjuvant improved the antibody titres and avidity, while the inoculation pathway had no influence. T helper type 1/ type 2 immune responses were balanced induced by HBoV1 VLPs but not HBoV2 VLPs. Serum IgG antibody cross‐reactivity rates of the two subtypes were similar, but cross‐reactions of HBoV1 immunization groups were higher. The single i.m. group had more interferon‐γ‐secreting splenocytes. These data indicate that HBoV VP2 VLPs have good immunogenicity with induction of strong humoral and cellular immune responses, and they may be potential candidate vaccines for HBoV infection.  相似文献   
940.
Regulatory T (Treg) cells play an important role in the maintenance of immune self-tolerance and homeostasis. We previously reported that neonatal CD4+ T cells have an intrinsic ‘default’ mechanism to become Treg (neoTreg) cells in response to T-cell receptor (TCR) stimulation. However, the underlying mechanisms are unclear and the effects of neoTreg cells on regulating immune responses remain unknown. Due to their involvement in Foxp3 regulation, we examined the role of DNA methyltransferase 1 (DNMT1) and DNMT3b during the induction of neoTreg cells in the Foxp3gfp mice. The function of neoTreg cells was assessed in an acute allograft rejection model established in RAG2−/− mice with allograft cardiac transplantation and transferred with syngeneic CD4+ effector T cells. Following ex vivo TCR stimulation, the DNMT activity was increased threefold in adult CD4+ T cells, but not significantly increased in neonatal cells. However, adoptively transferred neoTreg cells significantly prolonged cardiac allograft survival (mean survival time 47 days, P < 0·001) and maintained Foxp3 expression similar to natural Treg cells. The neoTreg cells were hypomethylated at the conserved non-coding DNA sequence 2 locus of Foxp3 compared with adult Treg cells. The DNMT antagonist 5-aza-2′-deoxycytidine (5-Aza) induced increased Foxp3 expression in mature CD4+ T cells. 5-Aza-inducible Treg cells combined with continuous 5-Aza treatment prolonged graft survival. These results indicate that the ‘default’ pathway of neoTreg cell differentiation is associated with reduced DNMT1 and DNMT3b response to TCR stimulus. The neoTreg cells may be a strategy to alleviate acute allograft rejection.  相似文献   
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