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101.
Abdelhadi Lahoum Nasserdine Sabaou Christian Bijani Noureddine Bouras Frédéric Pont Selma P. Snini Florence Mathieu 《Saudi Pharmaceutical Journal》2019,27(1):56-65
The actinobacterium strain ABH26 closely related to Saccharothrix xinjiangensis, isolated from an Algerian Saharan soil sample, exhibited highly antagonist activity against Gram-positive bacteria, yeasts and filamentous fungi. Its ability to produce antimicrobial compounds was investigated using several solid culture media. The highest antimicrobial activity was obtained on Bennett medium. The antibiotics secreted by strain ABH26 on Bennett medium were extracted by methanol and purified by reverse-phase HPLC using a C18 column. The chemical structures of the compounds were determined after spectroscopic (1H NMR, 13C NMR, 1H-1H COSY and 1H-13C HMBC spectra), and spectrometric (mass spectrum) analyses. Two new cyanogriside antibiotics named cyanogriside I (1) and cyanogriside J (2), were characterized along with three known caerulomycins, caerulomycin A (3), caerulomycin F (4) and caerulomycinonitrile (5). This is the first report of cyanogrisides and caerulomycins production by a member of the Saccharothrix genus. The minimum inhibitory concentrations (MIC) of these antibiotics were determined against pathogenic microorganisms. 相似文献
102.
目的探讨先天性中枢性低通气综合征(CCHS)的临床和基因变异特征。方法分析1例首发表现为不明原因肺动脉高压的CCHS患儿的临床资料,并总结国内外文献中CCHS病例的临床特点、致病机制和基因变异情况。结果11月龄女婴,主要表现为浮肿、尿少、低血压、嗜睡、发绀、抽搐及颅内压增高。B型脑利钠肽、丙氨酸氨基转移酶升高,凝血酶原时间延长。颅脑磁共振示右侧额叶出血;超声心动图示中重度肺动脉高压。靶向捕获二代测序未发现可能的致病基因。采用Sanger法验证示患儿PHOX 2 B基因第3外显子存在多聚丙氨酸重复扩展变异,基因型为20/25。患儿入院后采用无创通气,睡眠时呼吸浅慢、微弱,伴血氧下降;血气分析提示二氧化碳潴留。随后改用夜间无创通气、降肺压药物治疗。复查肺动脉压力明显下降,生命体征稳定。随访至24月龄,夜间只需较低压力水平的无创通气,生长发育无异常。结论对于不明原因的肺动脉高压伴撤机困难患儿,需警惕CCHS。疑诊者应尽早针对CCHS相关基因进行靶向捕获二代测序及PHOX 2 B基因Sanger法验证。早期给予无创通气有望改善预后。 相似文献
103.
Takaharu Negoro Kanami Orihara Tomoko Irahara Hiroshi Nishiyama Kanae Hagiwara Risa Nishida Hiroki Takagi Kazue Satoh Yoshiki Yamamoto Shunichi Shimizu Tamio Hagiwara Masakazu Ishii Toshihiro Tanioka Yasuko Nakano Ken Takeda Isao Yoshimura Yoji Iikura Takashi Tobe 《Pediatric allergy and immunology》2006,17(8):583-590
Although many single nucleotide polymorphism (SNP) studies have reported an association of atopy, allergic diseases and total serum immunoglobulin E (IgE) levels, almost all of these studies sought risk factors for the onset of these allergic diseases. Furthermore, many studies have analyzed a single gene and hardly any have analyzed environmental factors. In these analyses, the results could be masked and the effects of other genes and environmental factors may be decreased. Here, we described the correlation between four genes [interleukin (IL)-4 (C-590T), IL-4 receptor (A1652G), FCER1B (G6842A) and STAT6 (G2964A)] in connection with IgE production; the role of IL-10 (C-627A) as a regulatory cytokine of allergy; and the severity of food allergy (FA) and atopic eczema (AE) in 220 Japanese allergic children. In addition to these SNPs, environmental factors, i.e., patient's attitude, indoor environment, and so on, were also investigated in this study. Our study was retrospective, and the correlation was analyzed by our defined clinical scores divided into three terms: worst symptoms, recent symptoms and general amelioration at the most recent examination during the disease course. Our results indicated that IL-10 AA, the genotype with lower IL-10 production, is associated with higher IgE levels in the serum (p < 0.0001, estimate; 0.912). Marginal liver abnormalities were observed in the subject group with both FA and AE (p < 0.1191, estimate; 0.1490). Our defined clinical scores enabled evaluation of various aspects of disease severity. Based on the scores, while no single SNP selected in this study determined severity, the combination of the SNP with laboratory data and environmental factors appeared to determine severity. 相似文献
104.
肝细胞核因子-κB异常激活与肝细胞癌变 总被引:3,自引:0,他引:3
核因子-κB(nuclear factor-κB,NF-κB)是具有和某些基因上启动子区固定核苷酸序列结合而启动该基因转录的蛋白质。NF-κB是具有多向性调节作用的核转录因子,可调控多种基因(免疫、炎症反应、病毒和原癌基因)的转录表达。激活的NF-κB参与癌症的启动、发生及发展过程,在炎症性相关的肝癌(HCC)发生发展中呈高表达,在肝细胞炎症与癌变间起桥梁作用,其中包括肝脏免疫炎症反应相关基因、肝炎病毒相关基因和原癌基因的转录表达。在肝癌组织中异常激活,可抑制细胞凋亡,促进肝细胞存活,与肝癌的发生发展密切相关。 相似文献
105.
S. Nishida J. J. Gaynor N. Nakamura F. Butt H. G. Illanes J. Kadono G. W. Neff D. M. Levi J. I. Moon G. Selvaggi T. Kato P. Ruiz A. G. Tzakis J. R. Madariaga 《American journal of transplantation》2006,6(1):140-149
A retrospective study of 1058 liver transplant recipients was performed to determine: (i) the incidence, etiology, timing, clinical features and treatment of refractory ascites (RA), (ii) risk factors for RA development, (iii) predictors of RA disappearance, (iv) predictors of survival following RA and (v) the impact of RA on patient survival. Sixty-two patients (5.9%) developed RA and its disappearance occurred in 27/62 cases. Patients having hepatitis C virus (HCV) had a significantly higher hazard rate of developing RA (p < 0.00001). No other baseline characteristic was associated with RA. Cox stepwise regression analysis of the hazard rate of RA disappearance found two significant factors: HCV recurrence as the reason for developing RA implied a poorer outcome (p = 0.006), whereas an unknown reason implied a favorable outcome (p = 0.02). In addition, survival following RA was significantly poorer among patients having bacterial peritonitis or HCV recurrence. Finally, the mortality rate was significantly (nearly 8.6 times) higher in patients following RA development while it was ongoing (p < 0.00001); however, if the RA disappeared, then the additional risk of death also disappeared. This study illustrates the importance of developing an optimal treatment strategy to (i) effectively treat RA if it develops and (ii) prevent hepatitis C recurrence. 相似文献
106.
Marieke C Wichers Gunter Kenis Carsten Leue Ger Koek Geert Robaeys Michael Maes 《Neuropsychopharmacology》2006,60(1):77-79
BACKGROUND: Major depression has been associated cross-sectionally with increased cell-mediated immune activation but causality has been difficult to establish. This study prospectively investigated the hypothesis that baseline level of immune activation predicts the development of depression during interferon-alpha (IFN-alpha) treatment. METHODS: Sixteen hepatitis C patients without psychiatric disorder underwent IFN-alpha treatment. Proinflammatory and anti-inflammatory cytokines were determined before starting treatment. Presence of a major depressive disorder (MDD) was assessed at baseline and several times during treatment. RESULTS: Baseline soluble interleukin-2 receptor (sIL-2r), interleukin-6 (IL-6), and interleukin-10 (IL-10) concentrations were significantly increased in the five subjects that developed MDD during treatment compared with those that did not, with standardized effect sizes of 1.08, 1.16, and 1.25, respectively, controlling for marijuana use, cigarette smoking, and baseline level of depressive symptoms. CONCLUSIONS: Results suggest that increased immune activation, rather than an epiphenomenon, is a causal risk factor for the development of MDD. 相似文献
107.
目的从三列凹顶藻Laurenciatristicha中寻找具有多样性结构的倍半萜化学成分,供药理活性筛选。方法采用凝胶柱色谱、硅胶柱色谱、重结晶和高效液相色谱等方法进行分离;借助包括一维和二维NMR等波谱方法和X-单晶衍射鉴定化合物的结构;用MTT法对得到的化合物进行细胞毒活性评价。结果分离得到5个倍半萜类化合物,分别鉴定为海兔阿普里素(aplysin,)、海兔阿普里醇(aplysinol,)、去溴海兔阿普里醇(debro-moaplysinol,)、凹顶藻联苯(laurebiphenyl,)、约翰斯顿醇(johnstonol,);在人肿瘤细胞株HCT-8、Bel-7402、BGc-823、A549和HeLa模型上,化合物对所有细胞株均显示毒性,化合物对HeLa细胞显示中等强度的细胞毒活性,其他化合物对所有细胞株均无明显毒性,IC50均大于10.0μg/mL。结论化合物~均为首次从三列凹顶藻中得到,化合物对HeLa细胞具有中等强度的选择性细胞毒活性,化合物对所有细胞株均显示毒性。 相似文献
108.
109.
Dino Donataccio Francine Roggen Chantal De Reyck Catherine Verbaandert Monique Bodeus Jan Lerut 《Transplant international》2006,19(1):38-43
The use of livers from anti-hepatitis B core (HBc) positive donors can alleviate donor shortage. Nineteen of 367 (6%) adults receiving anti-HBc positive allografts [three were hepatitis B antigen (HBsAg) negative, hepatitis B antibody (HBsAb) positive; four were HBsAg positive and 12 were not exposed to hepatitis B viral (HBV) infection] were retrospectively reviewed. In HBsAg negative recipients, immunoprophylaxis (IP) was guided by viral serology and immunohistochemistry (IH) of day 0 and day 7 liver biopsies. If IH was negative, IP was stopped. None of three HBsAg negative, HBsAb positive recipients infected; one (replicating) of four HBsAg positive recipients reinfected and seven of eight (87.5%) HBsAg, HBsAb negative recipients, who did not receive long-term IP, infected after a median time of 2 years (range 1-5); one patient died of liver failure. Four HBsAg, HBsAb negative recipients, receiving life-long IP, remained infection free. Anti-HBc positive donor livers must be directed selectively first to HBsAg positive recipients, next to recipients having HBV antibodies and finally to HBV-naive recipients. Identification of both donor and recipient risk factors for HBV infection before transplantation allows indiscriminate use of antiviral prophylaxis. The necessity for IP therapy should be guided by HBV-DNA testing of donor liver tissue and serum. IH of early liver biopsies is an unreliable marker for predicting antiviral treatment requirements. 相似文献
110.
凯时治疗慢性重型肝炎患者疗效观察 总被引:2,自引:0,他引:2
目的探讨凯时即前列地尔脂微球载体制剂(Lipo-PGE1)治疗慢性重型肝炎的疗效。方法将84例慢性重型肝炎患者随机分成两组,对照组予综合治疗及对症治疗,治疗组在该基础上加用凯时10μg溶于5%葡萄糖注射液250ml中静脉缓慢滴注,1次/d,疗程为4周。结果治疗组对慢性重型肝炎的疗效优于对照组(P〈0.01),肝功能改善优于对照组(P〈0.01)。结论Lipo-PCEI是一种治疗慢性重型肝炎安全、有效的药物。 相似文献