Do ethnicity and gender have an impact on pain thresholds in minor dermatologic procedures?

Background and Objectives: The perception of pain is a personal experience influenced by many factors, including genetic, ethnic and cultural issues. Understanding these perceptions is especially important in dermatologic patients undergoing minor surgical operations and who often differ in their pain response to surgical treatments. Little is known about how these differences affect the perception of experimental pain. The purpose of this study was to determine experimental pain perception differences in three distinct East Asian ethnic populations.
Methods: Pain thresholds were examined with a psychophysical computerized quantitative thermal sensory testing device (TSA 2001) in healthy volunteers recruited from three different Asian ethnic groups. Using the methods of limits, experimental pain perception threshold was measured on the forehead and volar aspect of the forearm in 49 healthy subjects. The measurements were then repeated after skin barrier perturbation with adhesive tape stripping of the stratum corneum. All three ethnic groups were analyzed separately with respect to age, gender educational level and skin type.
Results: A total of 20 Chinese, 14 Malay and 15 Indian subjects completed the study. Thermal pain thresholds were similar in all three ethnic groups before and after tape strippings. No significant differences were noted between genders.
Conclusions: Using quantitative sensory thermal testing, we demonstrated that no significant differences in pain occur between different races and genders.     

骨髓间质干细胞体外预构组织工程化肌腱的实验研究

目的探讨骨髓间质干细胞与胶原-聚羟基乙酸的细胞相容性,为构建组织工程化肌腱寻求理想方法.方法以贴壁法分离、培养骨髓间质干细胞,并检测CD44.在实验组中将骨髓间质干细胞置入含胶原-聚羟基乙酸的DMEM培基中培养:在对照组中将骨髓间质干细胞置入DMEM培基中培养.通过MTT方法比较两组的细胞活性和生长情况,并对实验组进行超微观察.以骨髓间质干细胞为种子细胞,以胶原-聚羟基乙酸为支架在体外预构组织工程化肌腱.结果以贴壁法原代培养骨髓间质干细胞,11天细胞即汇合成片,检测CD44示阳性.骨髓间质干细胞接种于胶原-聚羟基乙酸中混合培养后14天生长良好,始终保持89%以上的细胞活力,与对照组比较无显著差别;实验组细胞数未发生明显改变,而对照组从第4天开始即发生增殖.透射电镜示实验组细胞培养14天后仍保持旺盛的分泌功能.体外预构的组织工程化肌腱具有良好的形态,细胞伸展成梭形,沿聚羟基乙酸缝线大致平行排列.结论骨髓间质干细胞与胶原-聚羟基乙酸的细胞相容性好.以骨髓间质干细胞为种子细胞,以胶原-聚羟基乙酸为支架可在体外初步预构组织工程化肌腱.     

A型肉毒毒素多表位串联体的设计、表达、纯化及鉴定

目的:设计、表达两个A型肉毒毒素多表位串联体.方法:从文献报道的A型肉毒毒素(botulinum neurotoxin type A,BoNT/A)的表位及生物信息学方法预测得到的B细胞表位中遴选表位,并加入适当的辅助性元件,设计多表位串联体A、B.对其基因进行优化后,经重叠PCR方法合成串联体A、B的全长基因.分别插入原核表达载体pQE-30,再转化E.coli M15[pREP4]感受态细胞中进行诱导表达,以金属螯合亲和层析法纯化重组蛋白,并进行鉴定.结果与结论:成功设计并构建了两个多表位串联体A、B,并在E.coli中以包涵体形式获得高效表达.Ni-NTA法纯化后分别获得纯度大于92.2%、99%的重组串联体A、B蛋白,并经透析复性法复性.Western印迹和间接ELISA显示纯化、复性后的重组蛋白与抗天然BoNT/A马血清有特异性结合反应.     

中央型小细胞肺癌的CT诊断及鉴别诊断

目的:探讨中央型小细胞肺癌(Small Cell Lung Cancer,SCLC)的CT表现特点,并找出与非小细胞肺癌(NSCLC)、肺结核、结节病、纵隔淋巴瘤的鉴别诊断要点。方法:回顾性分析经病理证实的57例中央型SCLC、60例NSCLC,5例肺结核,2例结节病,3例纵隔淋巴病的胸部平片及CT资料,全部病例均行胸部平片和CT平扫、增强检查。结果:57例中央型SCLC,CT主要表现为沿支气管长轴生长的肺内肿块,肺门与纵隔广泛淋巴结肿大,而肺不张相对少见。NSCLC60例主要表现为肺门肿块,支气管阻塞性改变相对多见。5例肺结核表现为肺内结节和肺门、纵隔淋巴结肿大,伴有同侧和/或对侧肺内结核病灶。2例结节病,表现为双侧肺门对称性淋巴结肿大。3例纵隔淋巴病表现为中前纵隔的弥漫性软组织肿块。结论:沿支气管长轴生长的肺内肿块、肺门及纵隔淋巴结肿大。支气管阻塞改变少见,随访1～2个月,肿块体积增大1倍以上,是中央型SCLC的CT诊断要点,据此特征诊断正确率达80％。结合临床与其他检查方法可与NSCLC、肺结核、结节病、纵隔淋巴瘤鉴别。     

氟对体外培养人牙乳头间充质细胞合成I型胶原的影响

目的:明确氟对人牙乳头细胞合成 I型胶原的影响。 方法:对人牙乳头细胞进行体外培养 ,分别给予0 .0、0 .2× 10 - 6、1.0× 10 - 6、5 .0× 10 - 6、2 5 .0× 10 - 6 g/ L 氟处理 ,采用免疫细胞化学方法染色 ,图象分析氟对细胞合成 I型胶原的影响。 结果:I型胶原在对照组和 4种氟浓度处理组细胞表达均为阳性。图象分析结果表明 ,4种氟浓度对体外培养的人牙乳头细胞合成 I型胶原量与对照组相比差异无统计学意义 (P>0 .0 5 )。结论:过量氟对牙本质基质 型胶原的影响可能不是通过影响成牙本质细胞内合成实现的     

糖尿病脑内胰岛移植临床初步研究(附三例报告)

本文报告胰岛细胞脑内移植治疗I型糖尿病共3例,分别经过3个月、4个月、6个月的临床观察,其临床症状明显改善或消失,空腹血糖由移植前平均12.38mmol/L下降至7.77mmol/L;3例患者普通胰岛素用量平均每日62.3~u,移植后第21～30天均完全停用胰岛素,其中1例已持续撤离胰岛素治疗达5个月。观察结果提示:胰岛移植物在患者的脑内成活,并具有良好的内分泌功能。     

二甲双胍和罗格列酮对肥胖型PCOS治疗作用的对照性研究

目的观察罗格列酮和二甲双胍联合氯米芬治疗肥胖型多囊卵巢综合征患者的内分泌改善及生殖功能的临床疗效。方法50例肥胖型PCOS患者分别给予罗格列酮4mg/d和二甲双胍1500mg/d联合氯米芬100mg/d,治疗3个月,比较治疗前后体重指数、内分泌参数、腰臀比和Hom a IR的变化。结果用罗格列酮治疗后排卵率为88%,周期排卵率为64.29%,优势卵泡平均个数为1.8±0.8个,妊娠率为56%,而用二甲双胍治疗后分别为72%、54.84%、1.1±0.6个、48%。两者治疗后能使LH、LH/FSH、T的血清浓度明显下降,SHBG的浓度明显上升,Hom a IR明显改善。结论罗格列酮和二甲双胍联合氯米芬治疗肥胖型多囊卵巢综合征疗效可靠。二甲双胍有降低体重作用、价格便宜,适用于肥胖型P-COS伴胰岛素抵抗不严重者;罗格列酮在胰岛素增敏作用优于二甲双胍,适用于胰岛素抵抗较严重的PCOS患者。     

Viscoelastic properties of acid- and alkaline-treated human dermis: a correlation between total surface charge and elastic modulus

BACKGROUND: One of the major mechanical functions of collagenous tissues is the storage, transmission and dissipation of elastic energy during mechanical deformation. In skin, mechanical energy is stored during loading and then is transmitted and dissipated, which protects skin from mechanical failure. Thus energy storage (elastic properties) and dissipation (viscous properties) are important characteristics of extracellular matrices. METHODS: A uniaxial incremental stress relaxation test method has been used to characterize the time-dependent (viscous) and time-independent (elastic) properties of human dermis. Viscoelasticity was investigated in processed human dermis that was equilibrated at pHs of 3.0, 7.4 and 11.0 in an effort to study the link between electrostatic interactions within the collagen matrix and macroscopic tissue properties. RESULTS: Our results show that the solution pH and the charge on collagen significantly affected the high-strain elastic behavior of dermis; the elastic behavior of skin has previously been shown to be directly correlated with axial stretching of the collagen triple helix in crosslinked collagen fibrils. A positive linear correlation existed between the high-strain elastic modulus and both pH (R(2)=0.96) and the total number of charged residues on collagen (R(2)=0.93). These results provide in vitro/ex vivo evidence that charged groups on the surface of collagen molecules in processed human skin influence the high-strain elastic properties of dermis and are likely to be involved in elastic energy storage. CONCLUSION: It is proposed that the pH and charged residue dependency of the elastic modulus suggests that charged pair interactions and repulsions within and between collagen molecules are involved in elastic energy storage during stretching at high strains. It is hypothesized that elastic energy storage is associated with the stretching of pairs of charged amino acid residues that are found primarily in the flexible regions of collagen molecules.     

Incretin mimetics as a novel therapeutic option for hepatic steatosis.

BACKGROUND: Fat accumulation in the liver or non-alcoholic fatty liver disease (NAFLD) is regarded as a key pathogenic factor and component of the metabolic syndrome. It was reported that administration of the incretin mimetic exenatide reversed hepatic steatosis in an obese mouse model. We had the opportunity to study the effect of additional exenatide administration on liver fat content in a patient with type 2 diabetes. CASE REPORT: A 59-year-old male with poorly controlled type 2 diabetes was treated with exenatide in addition to metformin monotherapy. Following 44 weeks of exenatide therapy, mean the liver fat measured by liver spectroscopy declined from 15.8% to 4.3%. This dramatic decrease in liver fat was accompanied by significant beneficial changes in several cardiovascular disease risk factors and improvement of all liver enzymes, in particular alanine aminotransferase, the most important marker of liver steatosis. CONCLUSION: This case report suggests that the incretin mimetic exenatide decreases hepatic fat accumulation and may play a role in the future treatment of NAFLD, and the associated insulin resistance and cardiovascular risk factors in an ever-growing high-risk population.