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1.

Background

Rosacea is a chronic inflammatory skin condition whose etiology has been linked to mast cells and the antimicrobial peptide cathelicidin LL-37. Individuals with refractory disease have demonstrated clinical benefit with periodic injections of onabotulinum toxin, but the mechanism of action is unknown.

Objectives

To investigate the molecular mechanism by which botulinum toxin improves rosacea lesions.

Methods

Primary human and murine mast cells were pretreated with onabotulinum toxin A or B or control. Mast cell degranulation was evaluated by β-hexosaminidase activity. Expression of botulinum toxin receptor Sv2 was measured by qPCR. The presence of SNAP-25 and VAMP2 was established by immunofluorescence. In vivo rosacea model was established by intradermally injecting LL-37 with or without onabotulinum toxin A pretreatment. Mast cell degranulation was assessed in vivo by histologic counts. Rosacea biomarkers were analyzed by qPCR of mouse skin sections.

Results

Onabotulinum toxin A and B inhibited compound 48/80-induced degranulation of both human and murine mast cells. Expression of Sv2 was established in mouse mast cells. Onabotulinum toxin A and B increased cleaved SNAP-25 and decreased VAMP2 staining in mast cells respectively. In mice, injection of onabotulinum toxin A significantly reduced LL-37-induced skin erythema, mast cell degranulation, and mRNA expression of rosacea biomarkers.

Conclusions

These findings suggest that onabotulinum toxin reduces rosacea-associated skin inflammation by directly inhibiting mast cell degranulation. Periodic applications of onabotulinum toxin may be an effective therapy for refractory rosacea and deserves further study.  相似文献   
2.
This article describes a modified suture technique designed for the vertical repair of the anterior horn of the meniscus after arthroscopic decompression of a large meniscal cyst. This procedure comprises of three steps: first, the meniscus was pierced vertically using a suture hook and a No. 0 PDS suture. Second, both ends of the No. 0 PDS on the femoral and tibial surfaces of the meniscus were pulled to the outside of the joint capsule using a spinal needle preloaded with suture material. Finally, a skin incision was made adjacent to the suture materials, and both ends were tied. We recommend this technique not only for the vertical repair of the anterior horn of the meniscus after decompression of large meniscal cyst, but also to repair a longitudinal tear of the meniscus.  相似文献   
3.
【目的】探讨地塞米松的用药方式对孕妇糖代谢的影响。【方法】对 1999年 9月至 2 0 0 1年 1月在本院住院的15 0名不同用药方式使用地塞米松促胎儿肺成熟的孕妇进行研究 ,在用药前及用药后 18~ 2 4h抽取肘前静脉血查空腹血糖、血浆C肽 ,糖负荷后 2h血糖、血浆C肽。【结果】使用地塞米松后 ,空腹血糖值、糖负荷后 2h血糖值、空腹C肽及糖负荷后 2hC肽值较用药前高 ;用药方式对母体空腹血糖值和空腹C肽值的影响差异无统计学意义 (P >0 0 5 ) ,对母体糖负荷后 2h血糖值和糖负荷后 2hC肽值的影响差异有统计学意义 (P <0 0 5 ) ;不同糖代谢状态的受试者使用地塞米松后 ,空腹C肽值、糖负荷后 2hC肽值的改变差异有统计学意义 (P <0 0 5 )。【结论】孕妇使用地塞米松促胎儿肺成熟对母体的糖代谢均有一定程度的影响 ,用药过程中和用药后需严密监测母体血糖和胎儿宫内状况  相似文献   
4.
Cooking processes that gelatinize granules or disrupt structure might increase the glucose and insulin responses because a disruption of the structure of starch by gelatinization increases its availability for digestion and absorption in the small intestine. We hypothesized that the uncooked form of rice, which has a relatively low degree of gelatinization even though in powder form, would result in lower metabolic glucose and insulin responses compared with cooked rice (CR). To assess the effects of the gelatinization of rice on metabolic response of glucose and insulin, we investigated the glucose and insulin responses to 3 rice meals of different gelatinization degree in female college students (n = 12): CR (76.9% gelatinized), uncooked rice powder (UP; 3.5% gelatinized), and uncooked freeze-dried rice powder (UFP; 5.4% gelatinized). Uncooked rice powders (UP and UFP) induced lower glucose and insulin responses compared with CR. The relatively low gelatinization degree of UPs resulted in low metabolic responses in terms of the glycemic index (CR: 72.4% vs UP: 49.7%, UFP: 59.8%) and insulin index (CR: 94.8% vs UP: 74.4%, UFP: 68.0%). In summary, UPs that were less gelatinized than CR induced low postprandial glucose and insulin responses.  相似文献   
5.
目的探讨如何对新调入肿瘤科的护士进行专科教育的有关问题。方法帮助新护士尽快适应工作环境,进行必要的专科知识教育和专科技术传授,熟练掌握肿瘤病人的心理特点及健康教育技巧。结果新护士在调入1个月后能单独完成本职工作,未发生差错和事故,同事对新调入护士评价好,病人满意。结论护士长对新调入护士有目的地进行专科理论知识教育和专科技术操作传授,言传身教,对尽快提高新调入护士的工作能力,确保护理质量起着重要的作用。  相似文献   
6.
Objective: Two major changes have occurred in inguinal hernia repair during the last two decades: (i) the use of tension‐free mesh repair; and (ii) the application of laparoscopic technique for repair. The aims of the present study were to study: (i) how inguinal hernia repair was carried out; and (ii) the outcome of inguinal hernia repair in Hospital Authority (HA) hospitals. Methodology: This was a retrospective analysis on 8311 elective inguinal hernia repairs performed in 16 HA hospitals from January 2001 to December 2003. The mean age was 63.9 ± 14.2 years, and the male to female ratio was 22.0 : 1.0. Among these, 869 (10.5%) repairs were performed with the laparoscopic approach and 7442 (89.5%) repairs with the open approach. The proportion of laparoscopic hernia repair increased from 8.7% to 12.6%. Results: For open repair, 39% of cases were carried out with regional anaesthesia, 32% with general anaesthesia and 29% with local anaesthesia (LA). Furthermore, mesh repair was used in 88% of the patients. For laparosocpic repair, 98.4% of cases were carried out under general anaesthesia, and all patients had mesh repair using the totally extraperitoneal approach. A significantly higher proportion of bilateral repair and recurrent hernia repair was performed with the laparoscopic approach (P = 0.000). For primary unilateral repair, there was no significant difference in the postoperative length of stay (LOS) and the total LOS between the laparoscopic and the open surgery groups. No difference in LOS was found in recurrent hernia repair between the two groups. With respect to bilateral repair, both the preoperative LOS (P = 0.036) and total LOS (P = 0.039) were shorter in the laparoscopic group. Furthermore, a significantly higher proportion of day‐surgery patients was observed in the laparoscopic group than the open surgery group (21.3%vs 16.9%, P = 0.001). Nevertheless, when only the results of 2003 were analyzed, the postoperative LOS (P = 0.000) and total LOS (P = 0.000) were significantly shorter in the laparoscopic group than the open surgery group. The LOS parameters were significantly shorter in the open surgery LA subgroup compared with the non‐LA subgroup (P = 0.000), and they were not different from those in the laparoscopic group. Conclusions: The open mesh repair is the predominant approach for inguinal hernia repair in HA hospitals. The originally described local anaesthetic approach was under utilized, although it resulted in good outcome. The use of laparoscopic hernia repair is increasing and a learning curve was recently observed with improved outcome.  相似文献   
7.
Although studies exist using both male and female rats, there are virtually no studies that compare male and female bladder function. In this initial study, in-vivo and in-vitro urinary bladder function was investigated in two age groups of male and female rats (sexually immature and sexually mature). These studies compare in-vivo micturition behavior (water intake, urine output, frequency and volume per micturition); and in-vitro whole bladder function (bladder volume/pressure relationships, the ability of the in-vitro bladders to generate pressure and empty in response to bethanechol and field stimulation). The results can be summarized as follows: 1) The 24 hour water intake, urine output, and volume per micturition for the mature male rats was significantly greater than that of the mature females with no significant differences among the immature females, mature females, or immature males. 2) There were no significant differences in the frequency of micturition between the 4 groups. 3) Although the average plateau pressures (cystometrograms) of the immature and mature female bladders were greater than that of the immature and mature male bladders, the compliance was similar for all groups. 4) The maximum pressure response of the mature female bladder was significantly greater than pressures generated by bladders in the other three groups; there were no age or sex related differences in the bethanechol log ED50 values. 5) There were no age or sex-related differences in the bethanechol log ED50 values or maximal expulsion responses. 6) Field stimulated bladders from mature animals generated significantly greater intravesical pressures than bladders from immature animals, but, there were no significant differences in maximal pressures attained between mature male and female bladders nor between immature male and female bladders. In conclusion, micturition behavior, and the maximal pressure response to bethanechol changed dramatically with sexual maturity. These results are consistent with the idea that estrogen and other hormones may have a marked influence on bladder function and micturition behavior.  相似文献   
8.
Transforming growth factor-β1 (TGF-β1) is known to be a potent growth inhibitor for many cell types, including most epithelial cells. In skin keratinocytes, TGF-β1 has been shown to inhibit growth and to rapidly reduce c-mycexpression. However, the molecular mechanism of TGF-β1 action on cell growth of cervical carcinoma has not yet been elucidated. We thus assessed the effect of TGF-β1 on the growth of cervical carcinoma cell lines. Two cervical squamous carcinoma cell lines, CUMC-3 and CUMC-6, were incubated with varying concentrations of TGF-β1, and growth inhibition was evaluated with tetrazolium-based colorimetric assay. After culture in TGF-β1 for 24 h, inhibition of growth was detected in a dose-dependent manner at concentrations of 0.1–10 ng/ml in both cell lines. This effect of TGF-β1 on cultured carcinoma cells was associated with apoptotic process including oligonucleosomal ladder DNA and apoptotic body formations. Northern blot analysis revealed c-mycmRNA expression was suppressed by 10 ng/ml of TGF-β1 following 3 h of treatment in both cell lines. Western blot analysis showed that the level of p27Kip1protein was increased after TGF-β1 treatment in both cell lines. These results suggest that the mechanisms by which TGF-β1 inhibits the growth of cervical carcinoma are complex and may include effects on down-regulation of c-mycgene, and overexpression of p27Kip1protein.  相似文献   
9.
胃癌D17S261和D17S799位点二核苷酸重复序列不稳定性的意义   总被引:2,自引:2,他引:0  
目的研究二核苷酸重复序列不稳定性〔DRSI〕在胃癌发生中的作用及其临床意义.方法采用PCR方法检测了D17S261和D17S799位点二核苷酸重复序列不稳定性.结果胃癌总DRSI发生率为34%(17/50),其中高中分化腺癌DRSI阳性率(667%,10/15)显著高于低分化癌(194%,6/31,P<001);肠型胃癌DRSI阳性率(556%,10/18)显著高于胃型胃癌(20%,6/30,P<005),DRSI与胃癌部位、大小、浸润、分期、淋巴结转移无显著相关.结论DRSI在胃癌的发生中可能起重要作用.  相似文献   
10.
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