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71.
The overall goal of acne management for all patients is to select treatments that effectively address as many pathogenic factors as possible while minimizing side effects. Acne therapy in darker skin patients presents unique challenges due to differences in the risk of postinflammatory hyperpigmentation, which may develop in response to acne itself or to irritation secondary to treatment. One combination treatment currently available is a gel formulation containing a retinoid (adapalene 0.1%) in fixed combination with an antimicrobial (benzoyl peroxide 2.5%). Results from three randomized, double-blind, vehicle-controlled, clinical trials of adapalene-benzoyl peroxide were combined in a retrospective meta-analysis that included 909 patients treated for 12 weeks and assessed at each visit for erythema, scaling, dryness, and stinging/burning. Only Week 1 results were included in the meta-analysis because the worst severity of cutaneous irritation was found to occur at this timepoint in all three trials. For each study, and for the meta-analysis, comparisons were made using the Cochran-Mantel-Haenszel test. There were no statistically significant differences in dryness, scaling, and stinging/burning with adapalene-benzoyl peroxide treatment when subjects with Fitzpatrick skin types I to III were compared to subjects with Fitzpatrick skin types IV to VI (P=NS). Erythema assessments were statistically different based on skin types, as subjects with Fitzpatrick skin types IV to VI were rated as having “none” more often than those with Fitzpatrick skin types I to III (P<0.001). This could be due to the difficulty in visualizing erythema in patients with darker skin types, mainly Fitzpatrick skin types VI. Acne patients with Fitzpatrick skin types IV to VI were not found to be more susceptible to cutaneous irritation from treatment with the adapalene-benzoyl peroxide gel than patients with Fitzpatrick skin types I to III.Acne affects individuals of all races and ethnicities. The pathogenesis of acne is multifactorial, and the same factors are probably involved across the spectrum of skin types: sebaceous follicle obstruction, excessive sebum production due to hormonal stimulation of sebaceous glands, and proliferation of Propionibacterium acnes, which produces chemotactic factors and proinflammatory mediators that, in turn, generate an inflammatory response, followed by follicular rupture and extension of inflammation into the dermis, resulting in the formation of inflammatory lesions.1,2The overall goal of acne management in all patients is to select treatment that effectively addresses as many of the pathogenic factors as possible while minimizing side effects.3,4 Using multiple agents at the same time during treatment (concomitant therapy) has been recommended as a rational means to achieve this goal.5,6 Acne therapy in skin of color (high melanin content) presents unique challenges due to differences relating to acne sequelae in these skin types, especially the presence or risk of postinflammatory hyperpigmentation (PIH) and keloidal scarring,710 which are more prevalent in darker skin.1113Current acne treatment recommendations include combining gentle cleansing, effective moisturization, and sun protection, along with lower concentrations of benzoyl peroxide (BPO, 2.5%, 5%) and topical retinoids (adaplene 0.1%, tretinoin microsphere 0.04%, tazarotene 0.05%).6,7,14 These agents can then be titrated up to higher concentrations if tolerated by the patient. Recently, a fixed-dose combination product containing a retinoid (adapalene) in combination with an antimicrobial (BPO) became available. Retinoids, such as adapalene, tretinoin, and tazarotene, are ideally suited for acne therapy because they target key factors in hyperkeratinization and comedogenesis, and are anti-inflammatory.15 Adapalene itself possesses anticomedogenic, comedolytic, and anti-inflammatory properties.1619 Some studies have documented that retinoids in skin of color, in addition to effectively treating noninflammatory and inflammatory acne, may also improve PIH.2023 Antimicrobials, such as BPO, provide additional benefits. BPO is an oxidizing agent with antibacterial and keratolytic effects and is used in acne treatment for its activities in decreasing the bacterial population of P. acnes.2427 In addition, the nonclinical and clinical safety profile of BPO is well established.28Despite the benefits of combination therapy, the potential for increased cutaneous irritation is a concern. Although it has not been established that skin of color is more or less sensitive to irritants,29 PIH may be triggered in darker skinned patients by skin irritation independent of cause (i.e., a disease or iatrogenic cause).11,21,30 This issue has led some physicians to believe that skin of color is more sensitive to irritation from therapy. Because acne-related PIH is caused by a response to skin inflammation,7,8 minimizing inflammation and reducing potential irritation and dryness is also a key goal in treating acne in skin of color. This is why dermatologists who treat acne patients with darker skin strive for a balance between effectively treating acne lesions and recognizing the importance of tolerability.This meta-analysis of the cutaneous irritation of adapalene-BPO gel was conducted to investigate possible differences in the incidence and severity of irritation among patients with different skin types. Three randomized, double-blind, vehicle- and placebo-controlled, clinical trials involving 3,855 patients have established the safety and efficacy of adapalene-BPO gel in the treatment of acne for all skin types.3133 The present retrospective meta-analysis is based on the tolerability data from those patients who were assigned to the adapalene 0.1%–BPO 2.5% treatment arm in each of the three randomized trials.  相似文献   
72.
Loss of epidermal growth factor receptor (EGFR) activity in mice alters growth plate development, impairs endochondral ossification, and retards growth. However, the detailed mechanism by which EGFR regulates endochondral bone formation is unknown. Here, we show that administration of an EGFR-specific small-molecule inhibitor, gefitinib, into 1-month-old rats for 7 days produced profound defects in long bone growth plate cartilage characterized by epiphyseal growth plate thickening and massive accumulation of hypertrophic chondrocytes. Immunostaining demonstrated that growth plate chondrocytes express EGFR, but endothelial cells and osteoclasts show little to no expression. Gefitinib did not alter chondrocyte proliferation or differentiation and vascular invasion into the hypertrophic cartilage. However, osteoclast recruitment and differentiation at the chondro-osseous junction were attenuated owing to decreased RANKL expression in the growth plate. Moreover, gefitinib treatment inhibited the expression of matrix metalloproteinases (MMP-9, -13, and -14), increased the amount of collagen fibrils, and decreased degraded extracellular matrix products in the growth plate. In vitro, the EGFR ligand transforming growth factor α (TGF-α) strongly stimulated RANKL and MMPs expression and suppressed osteoprotegerin (OPG) expression in primary chondrocytes. In addition, a mouse model of cartilage-specific EGFR inactivation exhibited a similar phenotype of hypertrophic cartilage enlargement. Together our data demonstrate that EGFR signaling supports osteoclastogenesis at the chondro-osseous junction and promotes chondrogenic expression of MMPs in the growth plate. Therefore, we conclude that EGFR signaling plays an essential role in the remodeling of growth plate cartilage extracellular matrix into bone during endochondral ossification.  相似文献   
73.

Purpose

Breast-conserving therapy (BCT) is an accepted method of treating early breast cancer. We hypothesized that routine excision of additional cavity shave margins (CSM) at time of initial partial mastectomy reduces the need for additional surgery.

Methods

A single-institution retrospective review was performed of women, 18 years or older, with a new diagnosis of breast cancer who underwent partial mastectomy between 1 January 2004 and 1 October 2009. Five hundred thirty-three charts were reviewed. Of those, 69 patients underwent CSM at time of initial operation. These 69 patients were matched with patients who had undergone partial mastectomy without CSM by tumor size, presence of extensive intraductal component, and primary histology.

Results

The two groups were well matched for age, nuclear grade, associated lymphovascular invasion (LVI), receptor status, and multifocality. We found that 31.9% (44/138) required return to the operating room (OR) for re-excision of margins. Rate of return to the OR was 21.7% (15/69) in the CSM group and 42.0% (29/69) in the matched group (p = 0.011). Multivariate analysis found factors significantly associated with need for additional operation included lack of CSM (odds ratio 9.2, 95% CI 2.8–30.5, p = 0.0003), larger extent of intraductal component (odds ratio 7.0, 95% CI 1.8–27.0, p = 0.005), and lack of directed re-excision (odds ratio 6.4, 95% CI 1.7–25.1, p = 0.007).

Conclusions

CSM at time of initial partial mastectomy decreases rate of re-excision by as much as ninefold. CSM should be considered at time of initial operation to reduce the need for subsequent reoperation.  相似文献   
74.
The purpose of this prospective observational study was to evaluate the effectiveness of the Dynamic SpineCor brace for adolescent idiopathic scoliosis in accordance with the standardized criteria proposed by the Scoliosis Research Society Committee on Bracing and Nonoperative Management. They proposed these guidelines to make the comparison among studies more valid and reliable. From 1993 to 2006, 493 patients were treated using the SpineCor brace. Two hundred forty-nine patients met the criteria for inclusion, and 79 patients were still actively being treated. Overall, 170 patients have a definitive outcome. All girls were premenarchal or less than 1 year postmenarchal. Assessment of brace effectiveness included (1) percentage of patients who have 5 degrees or less curve progression, and percentage of patients who have 6 degrees or more progression; (2) percentage of patients who have been recommended/undergone surgery before skeletal maturity; (3) percentage of patients with curves exceeding 45 degrees at maturity (end of treatment); and (4) Two-year follow-up beyond maturity to determine the percentage of patients who subsequently underwent surgery. Successful treatment (correction, >5 degrees, or stabilization, +/-5 degrees) was achieved in 101 (59.4%) of the 170 patients from the time of the fitting of the SpineCor brace to the point in which it was discontinued. Thirty-nine immature patients (22.9%) required surgical fusion while receiving treatment. Two (1.2%) of 170 patients had curves exceeding 45 degrees at maturity. One mature patient (2.1%) required surgery within 2 years of follow-up beyond skeletal maturity. The conclusion drawn from these findings is that the SpineCor brace is effective for the treatment of adolescent idiopathic scoliosis. Moreover, positive outcomes are maintained after 2 years because 45 (95.7%) of 47 patients stabilized or corrected their end of bracing Cobb angle up to 2 years after bracing. Therapeutic study-investigating the results of treatment: level II.  相似文献   
75.
76.

Background

Although alcohol is a leading risk factor for osteonecrosis of the femoral head (ONFH) and its prevalence reportedly ranges from 20% to 45%, there are no unified classification criteria for this subpopulation. In 2015, Association Research Circulation Osseous decided to develop classification criteria for alcohol-associated ONFH.

Methods

In June of 2017, Association Research Circulation Osseous formed a task force to conduct a Delphi survey. The task force invited 28 experts in osteonecrosis/bone circulation from 8 countries. Each round of the Delphi survey included questionnaires, analysis of replies, and feedback reports to the panel. After 3 rounds of the survey, consensus was reached on the classification criteria. The response rates for the 3 Delphi rounds were 100% (round 1), 96% (round 2), and 100% (round 3).

Results

The consensus on the classification criteria of alcohol-associated ONFH included the following: (1) patients should have a history of alcohol intake >400 mL/wk (320 g/wk, any type of alcoholic beverage) of pure ethanol for more than 6 months; (2) ONFH should be diagnosed within 1 year after alcohol intake of this dose; and (3) patients should not have other risk factor(s).

Conclusion

ARCO-established classification criteria to standardize clinical studies concerning AA-ONFH.  相似文献   
77.
BackgroundStenotrophomonas maltophilia is one of the most common multi-drug resistant organisms causing pulmonary infections in CF patients. It is unknown whether S. maltophilia infection follows the same pattern and shares similar risk factors for acquisition as described for Pseudomonas aeruginosa.MethodsWe examined all clinical events from 1997 to 2008 in the Toronto CF Database to identify risk factors for the acquisition of S. maltophilia and to define distinct patterns of infection.ResultsWe followed 601 patients over 12 years, during which time one quarter of subjects had at least one positive culture for S. maltophilia; the incidence rate was slightly higher in children (11.6/100 person years) compared with adults (10.6/100 person years). Using multi-variable Cox proportional hazards models, steeper rate of FEV1 decline was a significant risk factor for S. maltophilia acquisition, whereas new infections were less likely to occur with greater oral antibiotic use and a history of Burkholderia cepacia complex infection.ConclusionsThis study illustrates the evolution of S. maltophilia infection over time in a large cohort of adults and children with CF. Younger CF patients, and those with greater lung function decline were at increased risk of S. maltophilia infection. The use of oral antibiotics to maintain lung function may be a way of decreasing the risk of infection. However, the optimal management of CF patients with persistent S. maltophilia infection is not yet known and requires further studies.  相似文献   
78.

Background  

This study compared the prognostic value of exercise single-photon emission computed tomographic (SPECT) thallium imaging with that of treadmill exercise score in medically treated patients with coronary artery disease (CAD)  相似文献   
79.
A 713-base-pair Hae III fragment from bacteriophage T4 encompassing the denV gene with its preceding promoter has been cloned in a pBR322-derived positive-selection vector and introduced into a variety of DNA repair-deficient uvr and rec and uvr,rec Escherichia coli strains. The denV gene was found to be expressed, probably from its own promoter, causing pyrimidine dimer incision-deficient uvrA, uvrB, uvrC strains to be rescued by the denV gene. A uvrD (DNA helicase II) strain was also complemented, but to a lesser extent. A wild-type strain did not seem to be affected at the UV doses tested. Surprisingly, all recA, recB, and recC strains tested also showed an increased UV resistance, perhaps by reinforcement of the intact uvr system in these strains. Complementation of denV- T4 strains and host-cell reactivation of lambda phage was also observed in denV+ E. coli strains. Equilibrium sedimentation showed that DNA repair synthesis occurred in a UV-irradiated uvrA E. coli strain carrying the cloned denV gene. Southern blotting confirmed our earlier results [Valerie, K., Henderson, E. E. & de Riel, J. K. (1984) Nucleic Acids Res. 12, 8085-8096] that the denV gene is located at 64 kilobases on the T4 map. Phage T2 (denV-) did not hybridize to a denV-specific probe.  相似文献   
80.
The denV gene of phage T4, encoding the pyrimidine dimer-specific DNA repair enzyme endonuclease V, has been introduced by DNA transfection into the UV-sensitive DNA repair-deficient Chinese hamster ovary (CHO) cell line UV5. Transformants were first selected for resistance to the antibiotic G418 conferred by the neo gene from Tn5 carried by the same plasmid. A majority of the isolated G418-resistant UV5 clones also showed an increased resistance to 254-nm UV light. One clone, designated I-A1, was found to have an intermediate level of colony-forming ability after UV irradiation when compared to UV5 and wild-type AA8 cells. A Southern blot showed that I-A1 carries a single integrated intact copy of the denV gene. Alkaline sucrose gradients revealed a dose-dependent appearance of breaks in the DNA of I-A1 cells following UV-irradiation, while unirradiated cells did not exhibit any significant breaks. Analysis of DNA repair by isopycnic sedimentation showed that DNA excision repair by I-A1 was at least equal to the level of repair in AA8 cells. These results show that the prokaryotic denV gene can restore UV repair capabilities in vivo to CHO UV5 cells defective in repair of UV-induced damage.  相似文献   
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