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991.
Blockade of LTB4-induced chemotaxis by bioactive molecules interfering with the BLT2-Gαi interaction
BLT2, a low-affinity leukotriene B4 (LTB4) receptor, is a member of the G-protein coupled receptor (GPCR) family and is involved in the pathogenesis of inflammatory diseases such as asthma. Despite its clinical implications, however, no pharmacological inhibitors are available. In the present study, we screened for small molecules that interfere with the interaction between the third intracellular loop region of BLT2 (BLT2iL3) and the Gαi3 protein subunit (Gαi3), using a high-throughput screening (HTS) assay with a library of 1040 FDA-approved drugs and bioactive compounds. We identified two small molecules—purpurin [1,2,4-trihydroxy-9,10-anthraquinone; IC50 = 1.6 μM for BLT2] and chloranil [tetrachloro-1,4-benzoquinone; IC50 = 0.42 μM for BLT2]—as specific BLT2-blocking agents. We found that blockade of the BLT2iL3-Gαi3 interaction by these small molecules inhibited the BLT2-downstream signaling cascade. For example, BLT2-signaling to phosphoinositide-3 kinase (PI3K)/Akt phosphorylation was completely abolished by these molecules. Furthermore, we observed that these small molecules blocked LTB4-induced chemotaxis by inhibiting the BLT2-PI3K/Akt-downstream, Rac1-reactive oxygen species-dependent pathway. Taken together, our results show that purpurin and chloranil interfere with the interaction between BLT2iL3 and Gαi3 and thus block the biological functions of BLT2 (e.g., chemotaxis). The present findings suggest a potential application of purpurin and chloranil as pharmacological therapeutic agents against BLT2-associated inflammatory human diseases. 相似文献
992.
Dolores Acevedo-Garcia Lisa M. Bates Theresa L. Osypuk Nancy McArdle 《Social science & medicine (1982)》2010
Global self-rated health (SRH) is increasingly a key indicator in the assessment of immigrant health. However, evidence of the impact on SRH of generational status, duration of residence in the US, and socioeconomic status (SES) among immigrants and their offspring is limited and inconsistent. We overcome limitations in existing research on this topic by using a uniquely large and diverse data source, the March Annual Social and Economic Supplement of the Current Population Survey (CPS; 2003–2007) (n = 637,209). As a result, we are able to disaggregate results by race/ethnicity, account for country of origin, and consider the role of multiple dimensions of SES. We find that overall first-generation immigrants in the US have lower odds of poor/fair SRH compared to the third-generation. This association is particularly strong for blacks and Hispanics but not significant for Asians. Among first-generation Asians and Hispanics, longer duration of residence is positively associated with poor/fair SRH. Finally, socioeconomic gradients in SRH tend to be less pronounced among the first-generation (versus the third) and, within the first-generation, among recent arrivals (versus those with longer durations). Our results highlight the importance of explicitly accounting for multiple immigration-related variables and their interactions with race/ethnicity and SES. Otherwise, studies may misestimate SRH differences by race/ethnicity and socioeconomic status. The continued growth of the US immigrant population and the second-generation underscore the need to examine patterns in immigrant health systematically. 相似文献
993.
994.
目的为探讨结直肠癌术后复发的原因、诊断和术后复发的治疗效果。方法笔者回顾性分析10年间收治的60例结直肠癌术后复发患者的临床资料。结果手术后2年内复发40例(66.7%)。60例中吻合口处复发15例,腹腔、盆腔内复发20例,会阴部复发10例,肝脏转移8例,腹壁切口复发7例。全组患者均再次行手术治疗,其中根治性切除38例,姑息性切除22例。再手术后的1,3,5年生存率根治性切除分别为93.6%,48.8%,36.3%;姑息性切除为54.5%,0,0。结论重视术中无瘤技术、切除足够的肠管、彻底清除淋巴结及其所在的肠系膜、消灭微小转移灶是预防结直肠癌术后复发的主要措施。对复发患者应根据复发部位、病期早晚选择以手术为主的综合治疗方案。 相似文献
995.
霍新合 《中国普通外科杂志》2007,16(12):4-114
目的探讨十二指肠镜联合腹腔镜治疗胆囊结石并胆管结石的临床效果。方法回顾分析7年间106例胆囊结石并胆管结石患者的临床资料。106例均先行内镜下十二指肠乳头切开(EST)取石、鼻胆引流(ENBD)然后行腹腔镜胆囊切除术(LC)。结果EST取石成功101例(95.3%);并发症包括胰腺炎(高淀粉酶血症)11例(10.4%),出血1例,急性胆管炎2例,均经对症处理治愈。全组病例无死亡,均痊愈出院。85例获平均3.1年随访,术后复发胆管结石5例(5.9%),十二指肠乳突部再狭窄1例;另发生胆管癌2例,其他原因死亡2例。结论联合EST和LC治疗肝外胆管结石是一种安全有效的微创手术方法。 相似文献
996.
Physical activity is an important, but often underused, therapeutic strategy within diabetes care. To date, little is known about the best way to promote physical activity in diabetes care. Physical activity consultation is an intervention designed to promote physical activity behaviour change. This article provides guidelines on how to conduct a physical activity consultation with people who have Type 2 diabetes, and reviews the evidence surrounding the effectiveness of this intervention in this population. The trans-theoretical model is the underlying theory of behaviour change for the physical activity consultation intervention. The review identifies research which supports the use of this model for understanding physical activity behaviour in people with Type 2 diabetes. The review outlines a number of modifiable variables associated with physical activity behaviour change in this population. How each of these variables is addressed within the guidelines for conducting a physical activity consultation is identified. Finally, limited but consistent research highlights the effectiveness of physical activity consultation for promoting physical activity in people with Type 2 diabetes. 相似文献
997.
C Piérard-Franchimont P Paquet P Quatresooz GE Piérard 《Journal of the European Academy of Dermatology and Venereology》2007,21(5):657-661
BACKGROUND: The observation of photo-exposed skin under ultraviolet light reveals a mosaic pattern of varying intensity in epidermal melanization. Several patterns of mosaic subclinical melanoderma (MSM) have been described using a specially designed CCD camera and the ultraviolet light-enhanced visualization (ULEV) method. Vitamin D(3) and its analogues influence the biology of keratinocytes and melanocytes. OBJECTIVE: To assess the effect of calcipotriol on MSM. METHODS: This randomized split-face study was conducted in 27 men to compare the effect of once daily applications of 5% calcipotriol cream or a moisturizing cream on the heterogeneity of facial MSM. Computerized image analysis of video images was used at 1-month intervals before and during a 2-month treatment, as well as during a 3-month follow-up. RESULTS: At both sites, the average melanin content of the epidermis showed no significant change over time. However, the mottled appearance was smoothened at the calcipotriol site, whereas it was increased at the site receiving the moisturizer. CONCLUSION: The decreased heterogeneity in MSM after calcipotriol applications suggests a control of the epidermal melanocyte unit by the vitamin D(3) derivative. 相似文献
998.
Distension-induced gastric accommodation in functional dyspepsia: effect of autonomic manipulation 总被引:2,自引:0,他引:2
j. a. lunding o. h. gilja † t. hausken † a. bayati ‡ h. mattsson ‡ & a. berstad 《Neurogastroenterology and motility》2007,19(5):365-375
Functional dyspepsia (FD) is associated with impaired gastric accommodation and autonomic dysregulation. The aim of this study was to investigate the effects of autonomic manipulation on distension-induced gastric accommodation in subjects with and without FD, using a newly developed gastric barostat paradigm. Twelve healthy subjects (HS) and 18 subjects with FD had four barostat examinations each: no intervention, intravenous atropine (1 mg), vagal stimulation (mental relaxation with deep breathing) and acute stress stimulation (serial subtraction task). Intrabag pressure increased from 1 to 15 mmHg in 5 min (ramp phase), and was maintained at 15 mmHg for 5 min (tonic phase). Volume responses were analysed using predefined parameters. There were no significant group differences in accommodation variables between HS and subjects with FD. The FD group could be subdivided into two distinct subgroups: subgroup 1 (n = 7, 38%) with low maximum volume and accommodation rate, and subgroup 2 with normal accommodation (n = 11). In subgroup 1, but not in subgroup 2 atropine increased maximum volume and accommodation rate substantially. Neither mental stress nor mental relaxation changed any of the accommodation variables. In a subgroup of subjects with FD, impairment of distension-induced gastric accommodation can be improved by cholinergic blockade, but not by acute physiological autonomic manipulation. 相似文献
999.
Zhipan Zhang Gaoquan Shi 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2004,569(2):197-202
Poly (3-phenylthiophene) (P3PhT) films have been electrochemically synthesized by direct oxidation of 3-phenylthiophene in the electrolyte of pure boron trifluoride diethyl etherate (BFEE). The oxidation potential of the monomer was measured to be 1.29 V (vs. SCE), and about 0.15 V lower than that measured in a neutral medium of acetonitrile. Free-standing P3PhT film with tensile strength of 32–40 MPa has been obtained for the first time. The morphology and the structure of the polymer film have been studied by scanning electron microscopy, infrared and Raman spectroscopies. Raman spectral results demonstrated that the doping level of the P3PhT film increased with film thickness during electrochemical growth process. 相似文献
1000.
胰岛素样生长因子1对新生大鼠缺氧缺血性脑损伤保护机制的研究 总被引:1,自引:0,他引:1
目的 建立单侧缺氧缺血性脑损伤 (HIBD)动物模型 ,研究胰岛素样生长因子 1(IGF 1)对HIBD的影响和可能机制。 方法 选择健康 7日龄Wistar大鼠 12 0只 ,建立HIBD模型 ,随机分成假手术组、HIBD组、HIBD后 0 .2mg/kg人基因重组IGF 1干预组 (RH IGF 1组 )、0 .0 6 6mg/kg人基因重组IGF 1干预组 (SRH IGF 1组 )及盐水对照组 (对照组 )。各组按观察时段进一步分为 2 4、4 8、72h组 ,每组 8只。各组于规定时刻观测脑形态学改变、谷氨酸 (Glu)含量、凋亡细胞计数、Bcl 2蛋白表达。 结果 (1)HIBD 4 8h组Glu(116 2 .2± 10 8.1)mg/kg ,较假手术组(75 0 .9± 5 3.4 )mg/kg明显升高 (P <0 .0 5 ) ;HIBD组凋亡细胞计数 [2 4h :(7.6± 1.9) % ,4 8h(12 .6±1.2 ) % ,72h :(13.8± 0 .9) % ],较假手术组 [2 4h(2 .0± 0 .2 ) % ,4 8h(2 .0± 0 .3) % ,72h(2 .0±0 .2 ) % ]明显增加 (P均 <0 .0 5 )。 (2 )与对照组相比 ,RH IGF 1组脑组织病变减轻 ;干预 4 8h组Glu[SRH IGF 1组 (781.4± 5 4 .2 )mg/kg ,RH IGF 1组 (74 0 .5± 4 6 .6 )mg/kg],较对照组 (112 6 .6± 4 8.0 )mg/kg明显降低 (P均 <0 .0 5 ) ;RH IGF 1组凋亡细胞计数 [2 4h :(3.6± 0 .9) % ,4 8h(8.2± 2 .2 ) % ,72h(9.4± 1.4 ) % ],较对 相似文献