Skin permeation and metabolism of di(2-ethylhexyl) phthalate (DEHP)

Phthalates are suspected to be endocrine disruptors. Di(2-ethylhexyl) phthalate (DEHP) is assumed to have low dermal absorption; however, previous in vitro skin permeation studies have shown large permeation differences. Our aims were to determine DEHP permeation parameters and assess extent of skin DEHP metabolism among workers highly exposed to these lipophilic, low volatile substances.     

Shaving effects on percutaneous penetration: clinical implications

Context: Human/animal shaving biology.

Objective: To assess the effect of shaving on percutaneous penetration and skin function.

Methods: We screened 500+publications in Pub Med, Scopus, Cochrane Library and pertinent journals out of which only 17 were deemed relevant. Terms for searches included shaving and skin, percutaneous penetration and shaving, skin absorption and shaving, absorption of dyes and shaving, skin penetration, effects of shaving and absorption, shave and dyes, axillary shaving and stratum corneum, shaving and breast cancer, shaving and infections, etc.

Result: Shaving appears to have an exaggerated effect on percutaneous absorption; however, some studies do not support this evidence.

Conclusion: Shaving enhances percutaneous penetration of some chemicals; however this effect is species and chemical specific. Further investigations of chemicals of varying physio-chemical properties are mandated before a generalized theory can be promulgated.     

端粒酶与女性生殖功能

端粒酶是细胞中负责端粒延长的一种酶,通过合成染色体末端的DNA赋予细胞复制的永生性。其在保持端粒稳定、基因组完整、细胞长期的活性和潜在的继续增殖能力等方面有重要作用,端粒/端粒酶复合物的结构和功能的改变将会导致不同的疾病,尤其是癌症的发生。在人类正常生殖细胞、早期胚胎、干细胞、高度增殖体细胞和许多癌细胞中均有不同程度的端粒酶活性表达,并受到严密的调控。在女性生殖功能调控下,端粒酶活性表达在卵泡的发育及闭锁、子宫内膜的周期性变化、卵巢储备功能及性激素调节等方面发挥着重要的作用,并可在一定程度上预测卵巢储备功能及体外受精妊娠结局。     

19530例泌尿生殖道感染患者支原体感染及药敏结果分析

目的：分析该地区泌尿生殖道支原体感染及耐药状况,为临床合理用药提供依据。方法采用支原体培养、鉴定、药敏试剂盒对19530例泌尿生殖道感染患者的送检标本进行检测,分析支原体感染及药敏情况。结果19530例送检样本中,支原体阳性11178例,阳性率为57.24%,其中解脲支原体(Uu)、人型支原体(Mh)、Uu+Mh 混合感染阳性率分别为44.63%、0.44%和12.17%;女性支原体阳性率高于男性,差异有统计学意义(P <0.05);2008~2014年支原体阳性率呈上升趋势;支原体对交沙霉素、强力霉素、米诺环素、克拉霉素敏感率分别为88.57%、84.32%、76.09%、71.53%,对喹诺酮类抗菌药物耐药率高;Uu、Mh 和 Uu+Mh 3类感染对12种抗菌药物的耐药种数递增。结论泌尿生殖道感染以 Uu 感染为主,Mh 感染多以混合感染方式出现;交沙霉素、强力霉素是该地区治疗支原体的首选药物,临床可参考药敏结果合理用药。支原体多重耐药情况严重,应引起临床重视。     

2016-2019年南昌地区泌尿生殖道支原体感染现状及药敏分析

目的了解南昌地区泌尿生殖道支原体感染情况并进行药敏分析,为临床规范使用抗菌药物提供参考依据。方法对2016—2019年该院103254例疑似泌尿生殖道支原体感染患者的感染情况和药敏试验结果进行回顾性分析。结果103254例标本中共检出支原体阳性标本50970例,感染率为49.36%,其中解脲脲原体(Uu)感染41478例(40.17%),人型支原体(Mh)感染970例(0.94%),Uu+Mh混合感染8522例(8.25%);Uu感染率明显高于Mh和Uu+Mh,连续4年总体呈上升趋势,而Mh感染率呈下降趋势,Uu+Mh混合感染率相对稳定。女性Uu、Mh、Uu+Mh感染率分别为45.46%、1.08%、9.20%,明显高于男性的28.81%、0.64%、6.22%,差异有统计学意义(P<0.05)。≤20岁年龄段人群支原体感染率(51.32%)最高。Uu、Mh和Uu+Mh对强力霉素、美满霉素、四环素及交沙霉素敏感性较高,耐药率较低;Uu、Mh和Uu+Mh对喹诺酮类药物的敏感性均较低,耐药率较高;Uu对除交沙霉素外的大环内酯类药物阿奇霉素、克拉霉素和罗红霉素敏感性较高,对红霉素耐药率较高,而Mh和Uu+Mh对该类药物耐药率均较高;Uu、Mh和Uu+Mh对阿奇霉素、克拉霉素的耐药率连续4年逐年小幅下降。结论强力霉素、美满霉素、四环素及交沙霉素可首选用于该地区泌尿生殖道支原体感染的治疗。南昌地区Uu感染率总体呈上升趋势,应重视对该地区支原体感染的实时监控,加强临床对抗菌药物的合理使用。     

Design principles of chemical penetration enhancers for transdermal drug delivery

Chemical penetration enhancers (CPEs) are present in a large number of transdermal, dermatological, and cosmetic products to aid dermal absorption of curatives and aesthetics. This wide spectrum of use is based on only a handful of molecules, the majority of which belong to three to four typical chemical functionalities, sporadically introduced as CPEs in the last 50 years. Using >100 CPEs representing several chemical functionalities, we report on the fundamental mechanisms that determine the barrier disruption potential of CPEs and skin safety in their presence. Fourier transform infrared spectroscopy studies revealed that regardless of their chemical make-up, CPEs perturb the skin barrier via extraction or fluidization of lipid bilayers. Irritation response of CPEs, on the other hand, correlated with the denaturation of stratum corneum proteins, making it feasible to use protein conformation changes to map CPE safety in vitro. Most interestingly, the understanding of underlying molecular forces responsible for CPE safety and potency reveals inherent constraints that limit CPE performance. Reengineering this knowledge back into molecular structure, we designed >300 potential CPEs. These molecules were screened in silico and subsequently tested in vitro for molecular delivery. These molecules significantly broaden the repertoire of CPEs that can aid the design of optimized transdermal, dermatological, and cosmetic formulations in the future.