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51.
The role of simultaneous prophylactic diaphragmatic plication during major abdominal operations is evaluated. In five patients with a history of phrenic nerve injury, postoperative ventilation requirements and hospital stay were significantly reduced when synchronous diaphragmatic plication was performed, compared with corresponding values obtained during previous abdominal operation without diaphragmatic plication. In addition, diaphragmatic plication was associated with postoperative improvement of respiratory mechanics and blood gas exchange.  相似文献   
52.
There is mounting evidence that Th2 cytokines adversely affect skin barrier functions and contribute to the pathogenesis of atopic dermatitis (AD). AD is also characterized by abnormal cohesion in the stratum corneum (SC). However, the contribution of Th2 cytokines to this abnormality remains unknown. This study examined the effects of IL‐4, a prototypic Th2 cytokine, on the cohesion of the SC. Structural and physiological assessments revealed that repeated intradermal injections of IL‐4 compromised the cohesion of the SC of normal hairless mice. Two potential mechanisms were explored to account for the altered cohesion. First, IL‐4 decreased the amount of corneodesmosomes and down‐regulated the expression of desmoglein 1, but not of corneodesmosin (CDSN) or loricrin expression, in murine skin and in cultured human keratinocytes (KC). IL‐4 did not affect the skin surface pH, and in situ zymography revealed no net change in total serine protease activity in the IL‐4‐treated SC. Yet, IL‐4 enhanced expression of kallikrein (KLK)7, while simultaneously down‐regulating KLK5 and KLK14. Finally, IL‐4 did not alter the expression of the lympho‐epithelial Kazal‐type inhibitor (LEKTI) in KC. This study suggests that IL‐4 abrogates the cohesion of SC primarily by reducing epidermal differentiation.  相似文献   
53.
Course of macular edema in uveitis under medical treatment   总被引:1,自引:0,他引:1  
OBJECTIVE: To describe the response of uveitic macular edema to various treatment methods using optical coherence tomography (OCT). METHODS: This is a prospective study of consecutive uveitis patients with macular edema in at least one eye. The patients received medical treatment. Best corrected Snellen Visual Acuity (BCVA) and tomographic features of the macula, including macular thickness measurement, were obtained at one, three, six, and 12 months after commencing treatment. RESULTS: Eighty-one eyes of 58 patients were analyzed. Complete resolution of macular edema occurred in 38 eyes (47%). The average BCVA was 20/34 logarithm of minimum angle of resolution (-logMAR, 0.2 +/- 0.3) upon study entry and 20/27 (-logMAR, 0.13 +/- 0.29) upon study completion. The difference was statistically significant (p = 0.04). The corresponding mean retinal thickness at the central fovea was 319 +/- 150 microm at the beginning of the study compared to 241 +/- 125 microm at 12 months (p < 0.001). A weak but statistically significant correlation between the reduction of macular thickness and the improvement of BCVA (r = 0.3, p = 0.01) was found. Thirteen of the 43 eyes (30%) with persistent macular edema had a more than 15% reduction of macular thickness compared to baseline, whereas 10 eyes (23, 3%) had a more than 15% increase in macular thickness. Statistical analysis indicated that the presence of an epiretinal membrane and an OCT pattern of diffuse macular edema was a significant factor associated with medical treatment failure. CONCLUSION: This study demonstrates the overall favorable visual prognosis of uveitic macular edema under medical treatment. The presence of an epiretinal membrane is an important factor associated with medical treatment failure.  相似文献   
54.
BACKGROUND: Histopathological studies of acute multiple evanescent white dot syndrome (MEWDS) have not been reported because of the transient and benign nature of the disease. Ultrahigh resolution optical coherence tomography (UHR-OCT), capable of high resolution in vivo imaging, offers a unique opportunity to visualize retinal microstructure in the disease. METHODS: UHR-OCT images of the maculae of five patients with MEWDS were obtained and analyzed. Diagnosis was based on clinical presentation, examination, visual field testing, and angiography. RESULTS: UHR-OCT revealed disturbances in the photoreceptor inner/outer segment junction (IS/OS) in each of the five patients (six eyes) with MEWDS. In addition, thinning of the outer nuclear layer was seen in the case of recurrent MEWDS, suggesting that repeated episodes of MEWDS may result in photoreceptor atrophy. CONCLUSIONS: Subtle disruptions of the photoreceptor IS/OS are demonstrated in all eyes affected by MEWDS. UHR-OCT may be a useful adjunct to diagnosis and monitoring of MEWDS.  相似文献   
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The epidermal permeability barrier of premature infants matures rapidly following birth. Previous studies suggest that air exposure could contribute to this acceleration, because: (i) development of a structurally and functionally mature barrier accelerates when fetal rat skin explants are incubated at an air-medium interface, and (ii) occlusion with a water-impermeable membrane prevents this acceleration. To investigate further the effects of air exposure on epidermal barrier ontogenesis, we compared the activities of several key enzymes of lipid metabolism and gene expression of protein markers of epidermal differentiation in fetal rat skin explants grown immersed versus air exposed. The rate-limiting enzymes of cholesterol (HMG CoA reductase) and ceramide (serine palmitoyl transferase) synthesis were not affected. In contrast, the normal developmental increases in activities of glucosylceramide synthase and cholesterol sulfotransferase, responsible for the synthesis of glucosylceramides and cholesterol sulfate, respectively, were accelerated further by air exposure. Additionally, two enzymes required for the final stages of barrier maturation and essential for normal stratum corneum function, beta-glucocerebrosidase, which converts glucosylceramide to ceramide, and steroid sulfatase, which desulfates cholesterol sulfate, also increased with air exposure. Furthermore, filaggrin and loricrin mRNA levels, and filaggrin, loricrin, and involucrin protein levels all increased with air exposure. Finally, occlusion with a water-impermeable membrane prevented both the air-exposure-induced increase in lipid enzyme activity, and the expression of loricrin, filaggrin, and involucrin. Thus, air exposure stimulates selected lipid metabolic enzymes and the gene expression of key structural proteins in fetal epidermis, providing a biochemical basis for air-induced acceleration of permeability barrier maturation in premature infants.  相似文献   
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Liver X receptor-alpha and -beta are members of the nuclear hormone receptor superfamily that heterodimerize with retinoid X receptor and are activated by oxysterols. In recent studies we found that treatment of cultured human keratinocytes with oxysterolstimulated differentiation, as demonstrated by increased expression of involucrin and transglutaminase, and inhibited proliferation. The aims of this study were to determine: (i) whether oxysterols applied topically to the skin of mice induce differentiation in normal epidermis; (ii) whether this effect is mediated via liver X receptor-alpha and/or liver X receptor-beta; and (iii) whether oxysterols normalize epidermal morphology in an animal model of epidermal hyperplasia. Topical treatment of normal hairless mice with 22(R)-hydroxycholesterol or 24(S),25-epoxycholesterol resulted in a decrease in epidermal thickness and a decrease in keratinocyte proliferation assayed by proliferating cell nuclear antigen staining. Moreover, oxysterol treatment increased the levels of involucrin, loricrin, and profilaggrin protein and mRNA in the epidermis, indicating that oxysterols stimulate epidermal differentiation. Additionally, topical oxysterol pretreatment improved permeability barrier homeostasis. Whereas liver X receptor-alpha-/- mice revealed no alterations in epidermal differentiation, the epidermis was thinner in liver X receptor-beta-/- mice than in wild-type mice, with a reduced number of proliferating cell nuclear antigen positive cells and a modest reduction in the expression of differentiation markers. Topical oxysterol treatment induced differentiation in liver X receptor-alpha-/- mice whereas in liver X receptor-beta-/- mice there was no increase in the expression of differentiation markers. Whereas both liver X receptor-alpha and liver X receptor-beta are expressed in cultured human keratinocytes and in fetal rat skin, only liver X receptor-beta was observed on northern blotting in adult mouse epidermis. Finally, treatment of hyperproliferative epidermis with oxysterols restored epidermal homeostasis. These studies demonstrate that epidermal differentiation is regulated by liver X receptor-beta and that oxysterols, acting via liver X receptor-beta, can induce differentiation and inhibit proliferation in vivo. The ability of oxysterols to reverse epidermal hyperplasia suggests that these agents could be beneficial for the treatment of skin disorders associated with hyperproliferation and/or altered differentiation.  相似文献   
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Breast cancer is the most common invasive cancer among women in developed countries. Obesity is a major risk factor for breast cancer recurrence and mortality in both pre- and postmenopausal women. Co-morbid medical conditions are common among breast cancer survivors. The Exercise and Nutrition to Enhance Recovery and Good Health for You (ENERGY) study is a 4-year randomized clinical trial of 693 overweight/obese women aged ≥ 21 years diagnosed with any early stage breast cancer (stages I[≥ 1 cm]-III) within the previous five years, designed to demonstrate the feasibility of achieving sustained weight loss and to examine the impact of weight loss on quality of life and co-morbidities, and to enable future exploration of biochemical mechanisms linking obesity to lower likelihood of disease-free survival. This trial is strategically designed as a vanguard for a fully-powered trial of women who will be evaluated for breast cancer recurrence and disease-free survival. Participants were recruited between 2010 and 2012 at four sites, had completed initial therapies, and had a body mass index between 25 and 45 kg/m2. The intervention featured a group-based cognitive-behavioral weight loss program with telephone counseling and tailored newsletters to support initial weight loss and subsequent maintenance, with the goal of 7% weight loss at two years. This study has high potential to have a major impact on clinical management and outcomes after a breast cancer diagnosis. This trial initiates the effort to establish weight loss support for overweight or obese breast cancer survivors as a new standard of clinical care.  相似文献   
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