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61.
Background: Systemic isotretinoin has been known for decades to be effective in the treatment of severe forms of rosacea, but it must be used off‐label because of the lack of evidence‐based data. Patients and Methods: 573 patients with rosacea subtype II and III received one of three different dosages of isotretinoin (0.1 mg, 0.3 mg, or 0.5 mg per kg body weight), doxycycline (100 mg daily for 14 days, then 50 mg daily) or placebo in a double‐blinded, randomized way for 12 weeks in 35 German centers. Results: Isotretinoin 0.3 mg/kg proved to be the most effective dose with significant superiority versus placebo. Isotretinoin 0.3 mg/kg showed also significant non‐inferiority versus doxycycline with reduction of lesions of 90 % compared to 83 % with doxycycline. Investigators diagnosed complete remission in 24 % and marked improvement in further 57 % of patients with isotretinoin treatment, in contrast to remission in 14 % and marked improvement in 55 % of patients treated with doxycycline. Isotretinoin 0.3 mg/kg revealed a similar safety profile as for the treatment of acne. Isotretinoin 0.5 mg/kg showed more dermatitis facialis as compared to 0.3 mg/kg. Conclusions: Isotretinoin 0.3 mg/kg is an effective and well‐tolerated therapy option for the treatment of rosacea subtype II and III and can therefore be used successfully as an alternative to therapy with oral antibiotics.  相似文献   
62.
The protein tyrosine phosphatase (PTP) Shp2 (PTPN11) is an attractive target for anticancer drug discovery because it mediates growth factor signaling and its gain-of-function mutants are causally linked to leukemias. We previously synthesized SPI-112 from a lead compound of Shp2 inhibitor, NSC-117199. In this study, we demonstrated that SPI-112 bound to Shp2 by surface plasmon resonance (SPR) and displayed competitive inhibitor kinetics to Shp2. Like some other compounds in the PTP inhibitor discovery efforts, SPI-112 was not cell permeable, precluding its use in biological studies. To overcome the cell permeation issue, we prepared a methyl ester SPI-112 analog (SPI-112Me) that is predicted to be hydrolyzed to SPI-112 upon entry into cells. Fluorescence uptake assay and confocal imaging suggested that SPI-112Me was taken up by cells. Incubation of cells with SPI-112Me inhibited epidermal growth factor (EGF)-stimulated Shp2 PTP activity and Shp2-mediated paxillin dephosphorylation, Erk1/2 activation, and cell migration. SPI-112Me treatment also inhibited Erk1/2 activation by a Gab1-Shp2 chimera. Treatment of Shp2E76K mutant-transformed TF-1 myeloid cells with SPI-112Me resulted in inhibition of Shp2E76K-dependent cell survival, which is associated with inhibition of Shp2E76K PTP activity, Shp2E76K-induced Erk1/2 activation, and Bcl-XL expression. Furthermore, SPI-112Me enhanced interferon-γ (IFN-γ)-stimulated STAT1 tyrosine phosphorylation, ISRE-luciferase reporter activity, p21 expression, and the anti-proliferative effect. Thus, the SPI-112 methyl ester analog was able to inhibit cellular Shp2 PTP activity.  相似文献   
63.
BACKGROUND: The major side-effect of progestogen-only contraception is disruption of menstrual bleeding patterns, which can lead to a high incidence of early discontinuation. The aim of this study was to compare three treatments with placebo on the duration and recurrence of frequent and/or prolonged bleeding in Implanon users. METHOD: Women between the ages of 18 and 45 years, who had used Implanon for > or =3 months and were experiencing prolonged or frequent bleeding patterns, were recruited at four Australian sites. Subjects were randomized to treatment using computer-generated random number table if they met the World Health Organization criteria for prolonged and/or frequent bleeding in the previous 90 days [Belsey, E.M., Pinol, A.P.Y. and Taskforce on Long-Acting Systemic Agents for Fertility Regulation, World Health Organization (1997) Contraception 55,57-65]. Treatments were: (1) mifepristone 25 mg given twice on day 1 followed by 4 days of twice daily placebo; (2) mifepristone 25 mg given twice on day 1 followed by 4 days of ethinyl estradiol (EE) 20 microg in the morning and placebo at night; (3) doxycycline 100 mg twice daily for 5 days; and (4) placebo twice daily for 5 days. Analysis was by intention to treat. The primary endpoint was the number of days of bleeding and spotting immediately following initiation of the 5 day course of each active therapy compared with placebo. RESULTS: A total of 179 women was assigned to treatment. Both mifepristone in combination with EE and doxycycline alone were significantly more effective in stopping an episode of bleeding {mean 4. 3 days [confidence interval (CI) 3.5-5.2], and 4.8 days (CI 3.9-5.8) respectively} than mifepristone alone or placebo [5.9 days (CI 4.8-7.2) and 7.5 days (CI 6.1-9.1) respectively]. No effect on subsequent bleeding patterns was observed in any treatment group. CONCLUSION: Both mifepristone plus EE and doxycycline alone were significantly more effective than placebo in terminating an episode of bleeding in women with prolonged and/or frequent bleeding using Implanon. We believe that the observed reduction in the number of bleeding days by almost 50% compared to placebo in both the mifepristone combination group and the doxycycline group demonstrates a clinically significant improvement in bleeding patterns and that further trials are needed to compare different combinations of therapy as well as multiple dosing regimens in order to establish which is the most effective treatment option. The effect of repeat administration or combinations of these preparations on long-term bleeding patterns requires further investigation.  相似文献   
64.
The discovery of newly recognised pathogens and the emergence of antimicrobial resistance have led to the development of new antimicrobial agents or to new indications for older agents. The indications have continued to increase because of new discoveries on the older agents’ antimicrobial and non-antimicrobial activities. Macrolides and tetracyclines have received attention for their non-antimicrobial properties and potential use in chronic inflammatory disorders. Doxycycline, minocycline and trimethoprim-sulfamethoxazole regained interest for their activity against methicillin-resistant Staphylococcus aureus, whereas colistin has regained interest for its activity against multiple drug-resistant, Gram-negative pathogens (i.e., Pseudomonas aeruginosa). Despite the recent development of new antimicrobial agents, older and less costly agents maintain an important role today in the treatment of infectious diseases.  相似文献   
65.
[目的]观察中医药分期联合西药治疗真菌性角膜溃疡疗效。[方法]使用随机平行对照方法,将55例住院患者按病志号抽签简单随机分为两组。对照组27例氟康唑滴眼液与那他霉素滴眼液交替点眼,1次/h;托吡卡胺滴眼液,3次/d;妥布霉素滴眼液冲洗结膜囊,6次/d;维生素C,50mg/次,3次/d。治疗组28例早期龙胆泻肝汤(龙胆草12g,栀子9g,黄芩6g,柴胡12g,车前子10g,生地黄12g,泽泻、夏枯草、茯苓、厚朴各9g,甘草6g);中晚期托里消毒散(黄芪20g,当归、白芍、川芎、党参、白术、茯苓各10g,甘草6g,金银花15g,连翘、蝉蜕、白蒺藜各10g);水煎200mL,1剂/d,早晚口服;西药治疗同对照组。连续治疗20d为1疗程。观测临床症状、角膜、前房、视力、真菌菌丝、不良反应。治疗1疗程,判定疗效。[结果]治疗组痊愈11例,有效14例,无效3例,总有效率89.29%。对照组痊愈4例,有效14例,无效9例,总有效率66.67%。治疗组疗效优于对照组(P0.05)。[结论]中医药分期联合西药治疗真菌性角膜溃疡效果显著,值得推广。  相似文献   
66.
Background Frontal fibrosing alopecia (FFA) is a primary lymphocytic cicatricial alopecia with a distinctive clinical pattern of progressive frontotemporal hairline recession. Currently, there are no evidence‐based studies to guide treatment for patients with FFA; thus, treatment options vary among clinicians. Objectives We report clinical findings and treatment outcomes of 36 patients with FFA, the largest cohort to date. Further, we report the first evidence‐based study of the efficacy of hydroxychloroquine in FFA using a quantitative clinical score, the Lichen Planopilaris Activity Index (LPPAI). Methods A retrospective case note review was performed of 36 adult patients with FFA. Data were collected on demographics and clinical findings. Treatment responses to hydroxychloroquine, doxycycline and mycophenolate mofetil were assessed using the LPPAI. Adverse events were monitored. Results Most patients in our cohort were female (97%), white (92%) and postmenopausal (83%). Apart from hairline recession, 75% also reported eyebrow loss. Scalp pruritus (67%) and perifollicular erythema (86%) were the most common presenting symptom and sign, respectively. A statistically significant reduction in signs and symptoms in subjects treated with hydroxychloroquine (P < 0·05) was found at both 6‐ and 12‐month follow up. Conclusions In FFA, hairline recession, scalp pruritus, perifollicular erythema and eyebrow loss are common at presentation. Despite the limitations of a retrospective review, our data reveal that hydroxychloroquine is significantly effective in reducing signs and symptoms of FFA after both 6 and 12 months of treatment. However, the lack of a significant reduction in signs and symptoms between 6 and 12 months indicates that the maximal benefits of hydroxychloroquine are evident within the first 6 months of use.  相似文献   
67.
HIV-Tat protein has been implicated in the pathogenesis of HIV-1 neurological complications (i.e., neuroAIDS), but direct demonstrations of the effects of Tat on behavior are limited. GT-tg mice with a doxycycline (Dox)-inducible and brain-selective tat gene coding for Tat protein were used to test the hypothesis that the activity of Tat in brain is sufficient to impair learning and memory processes. Western blot analysis of GT-tg mouse brains demonstrated an increase in Tat antibody labeling that seemed to be dependent on the dose and duration of Dox pretreatment. Dox-treated GT-tg mice tested in the Barnes maze demonstrated longer latencies to find an escape hole and displayed deficits in probe trial performance versus uninduced GT-tg littermates, suggesting Tat-induced impairments of spatial learning and memory. Reversal learning was also impaired in Tat-induced mice. Tat-induced mice additionally demonstrated long-lasting (up to one month) deficiencies in novel object recognition learning and memory performance. Furthermore, novel object recognition impairment was dependent on the dose and duration of Dox exposure, suggesting that Tat exposure progressively mediated deficits. These experiments provide evidence that Tat protein expression is sufficient to mediate cognitive abnormalities seen in HIV-infected individuals. Moreover, the genetically engineered GT-tg mouse may be useful for improving our understanding of the neurological underpinnings of neuroAIDS-related behaviors.  相似文献   
68.
In recent years, coagulase‐negative staphylococci such as Staphylococcus epidermidis have gained importance as nosocomial pathogens, especially in immunocompromised patients and prosthetic joint infections (PJIs). These infections are often long lasting and difficult to treat due to the production of bacterial biofilm and the transformation of the bacteria into a stationary growth phase. Rifampicin is able to penetrate the biofilm, but to reduce the risk of development of rifampicin resistance it should be used in combination with an additional antibiotic. In this study we used Etest to investigate the antimicrobial susceptibility of 134 clinical isolates of S. epidermidis obtained from PJIs to six oral antibiotics: doxycycline, rifampicin, linezolid, fusidic acid, clindamycin, and ciprofloxacin. We also performed synergy testing on doxycycline in combination with each of the remaining antibiotics. Ninety‐three (69%) of the 134 isolates were susceptible to doxycycline, 94/134 (70%) to rifampicin, 56/134 (42%) to clindamycin, 25/134 (19%) to ciprofloxacin, 81/134 (60%) to fusidic acid, and 100% to linezolid. Thirty‐two (80%) of the 40 isolates not fully susceptible to rifampicin were susceptible to doxycycline. Doxycycline in combination with each of the other investigated antibiotics exerted an additive effect on nearly half of the isolates, with the exception of clindamycin, which displayed an even higher percentage of additive effect (69%). To conclude, as the majority of the S. epidermidis isolates were susceptible to doxycycline, this antimicrobial agent may provide a potential alternative for combination therapy together with rifampicin.  相似文献   
69.
目的 使用斑马鱼 (Danio rerio) 肝癌模型进行药物筛选,确定筛选方法和最适条件。方法 用不同浓度盐酸多西环素 (Dox) 处理转基因斑马鱼胚胎,诱导其肝脏异常增生,通过综合评价诱导效应与毒性效应,确定适合的诱导浓度;选择适宜的诱导浓度,对索拉非尼抑制肝部异常增生的能力进行评估。结果 确定了盐酸多西环素的最适诱导浓度为30~60mg/L,索拉非尼对斑马鱼模型的肝部异常增生有显著的抑制作用,同时也观察到药物的毒副作用。结论 该模型适用于索拉非尼及其类似物抗肝癌活性的评价与筛选,是评估化合物体内生物活性的快速筛选模型,同时也可以观测毒副作用,在其它抗肝癌药物及与Ras下游信号通路相关靶点的药物的筛选等方面具有广阔的应用前景。  相似文献   
70.
AIM: In the present 6-month multicentre trial, the outcome of 2 different approaches to non-surgical treatment of chronic periodontitis, both involving the use of a locally delivered controlled-release doxycycline, was evaluated. MATERIAL AND METHODS: 105 adult patients with moderately advanced chronic periodontitis from 3 centres participated in the trial. Each patient had to present with at least 8 periodontal sites in 2 jaw quadrants with a probing pocket depth (PPD) of > or =5 mm and bleeding following pocket probing (BoP), out of which at least 2 sites had to be > or =7 mm and a further 2 sites > or =6 mm. Following a baseline examination, including assessments of plaque, PPD, clinical attachment level (CAL) and BoP, careful instruction in oral hygiene was given. The patients were then randomly assigned to one of two treatment groups: scaling/root planing (SRP) with local analgesia or debridement (supra- and subgingival ultrasonic instrumentation without analgesia). The "SRP" group received a single episode of full-mouth supra-/subgingival scaling and root planing under local analgesia. In addition, at a 3-month recall visit, a full-mouth supra-/subgingival debridement using ultrasonic instrumentation was provided. This was followed by subgingival application of an 8.5% w/w doxycycline polymer at sites with a remaining PPD of > or =5 mm. The patients of the "debridement" group were initially subjected to a 45-minute full-mouth debridement with the use of an ultrasonic instrument and without administration of local analgesia, and followed by application of doxycycline in sites with a PPD of > or =5 mm. At month 3, sites with a remaining PPD of > or =5 mm were subjected to scaling and root planing. Clinical re-examinations were performed at 3 and 6 months. RESULTS: At 3 months, the proportion of sites showing PPD of < or =4 mm was significantly higher in the "debridement" group than in the "SRP" group (58% versus 50%; p<0.05). The CAL gain at 3 months amounted to 0.8 mm in the "debridement" group and 0.5 mm in the "SRP" group (p=0.064). The proportion of sites demonstrating a clinically significant CAL gain (> or =2 mm) was higher in the "debridement" group than in the "SRP" group (38% versus 30%; p<0.05). At the 6-month examination, no statistically significant differences in PPD or CAL were found between the two treatment groups. BoP was significantly lower for the "debridement" group than for the "SRP" group (p<0.001) both at 3- and 6 months. The mean total treatment time (baseline and 3-month) for the "SRP" patients was 3:11 h, compared to 2:00 h for the patients in the "debridement" group (p<0.001). CONCLUSION: The results indicate that simplified subgingival instrumentation combined with local application of doxycycline in deep periodontal sites can be considered as a justified approach for non-surgical treatment of chronic periodontitis.  相似文献   
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