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The region is characterized by diversity in cultural, political, economic and health conditions. Blindness in the region varies from 6.4% to 0.2% with cataract ranking highly as an underlying cause. There is a need to develop national policies to deliver affordable, technically suitable, and cost effective management plans to reduce cataract. Economic, demographic, health, and manpower statistics are essential information to be considered in formulating such policies.  相似文献   
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Maximal dynamic expiratory pressures are higher when forced expiration is preceded by a fast inspiration to total lung capacity (TLC) than when preceded by a slow inspiration and a few seconds pause at TLC. We hypothesized that these pressure differences are due to the stretch-shorten cycle (SSC), which refers to enhancement of muscle force when a concentric muscle contraction is immediately preceded by an eccentric contraction. Seven volunteers [36 (2) years; mean (SEM)] performed maximal forced expirations against minimal resistance with fast (F) or slow (S) maneuvers. F maneuvers consisted of a fast inspiration to TLC followed immediately by a fast expiration, whereas S consisted of a slow inspiration to TLC and a 4- to 5-s pause at TLC prior to forced expiration. We measured esophageal pressure (P es), peak expiratory flow rate (PEFR), and the EMG activity of the transversus abdominis (Tr) by means of intramuscular fine-wire electrodes. The subjects performed several runs of each maneuver in a random order, and runs with the greatest expiratory P es were analyzed. In comparison with S, F yielded greater P es [182 (15) versus 167 (15) cmH2O; P=0.003)] but similar PEFR [9.8 (0.7) versus 9.6 (0.7) l/s, P>0.05] and EMG activity of the Tr during forced expiration [221 (31) versus 208 (34) a.u., P>0.05]. Further analysis revealed significant EMG activity of Tr during end-inspiration (eccentric contraction) with F maneuvers only [73 (22) versus 32 (17) a.u., P<0.05]. We conclude that the ability of expiratory muscles to generate greater P es with F maneuvers is related to the sequence of an eccentric contraction, which is followed immediately by concentric contraction in a manner analogous to SSC described in skeletal muscles. Electronic Publication  相似文献   
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BACKGROUND: Melasma is a chronic hypermelanotic disorder that is challenging to treat; no single effective therapeutic agent for it has been discovered. Methimazole, an oral antithyroid drug, has a skin depigmenting effect when used topically. OBJECTIVE: We sought to evaluate the efficacy and safety of methimazole, applied during microneedling sessions and additional topical use in between sessions, for the treatment of melasma. METHODS: This split-face study included 30 Egyptian patients with melasma, each of whom received 12 microneedling sessions once per week for 12 weeks followed by topical methimazole on the right side of face and placebo on the left side. In between the sessions, topical methimazole 5% cream was applied twice per day on the right side and placebo on the left side. Assessments were performed using the Hemi-melasma Area and Severity Index (hemi-MASI) percentage of improvement, patient satisfaction, dermoscopy, and thyroid-stimulating hormone (TSH) serum levels. RESULTS: There were significant clinical and dermoscopic improvements; hemi-MASI scores on the methimazole-treated right sides were decreased (p<0.001). The percent of hemi-MASI score improvement was significantly associated with the malar pattern (p=0.031) and epidermal type (p=0.04) of melasma. About 70 percent of our studied patients reported being satisfied with their treatment response (7% excellent, 33% good, 30% fair). No significant local or systemic side effects were observed. Pre- and posttreatment serum TSH levels were within the normal range in all treated cases. CONCLUSIONS: Methimazole has the potential to be a safe and promising therapeutic agent for the treatment of melasma via dermapen-delivered microneedling sessions with topical use in between sessions.  相似文献   
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Acyclovir treatment was used in a randomized, double-blind, placebo-controlled clinical trial with parallel groups to test the hypothesis that herpes virus infections are involved in the pathogenesis of multiple sclerosis (MS). Sixty patients with the relapsing-remitting form of MS were randomized to either oral treatment with 800 mg acyclovir or placebo tablets three times daily for 2 years. The clinical effect was investigated by an extensive test battery consisting of neurological examinations, neuro-ophthalmological and neuropsychological tests, and evoked potentials. Results were based on intent-to-treat data and the primary outcome measure was the exacerbation rate. In the acyclovir group (n = 30), 62 exacerbations were recorded during the treatment period, yielding an annual exacerbation rate of 1.03. The placebo group (n = 30) had 94 exacerbations and an annual exacerbation rate of 1.57. Thus, 34% fewer exacerbations were encountered during acyclovir treatment. This difference in exacerbation rate between the treatment groups was not significant (P = 0.083). However, this trend to a lower disease activity in acyclovir-treated patients was supported in subsequent data analysis. If the patients were grouped according to exacerbation frequencies, i.e. into low (0–2), medium (3–5) and high (6–8) rate groups, the difference between acyclovir and placebo treatment was significant (P = 0.017). Moreover, in a subgroup of the population with a duration of the disease of at least 2 years providing an exacerbation rate base-line before entry, individual differences in exacerbation rates were compared between the 2-year pre-study period and the study period in acyclovir-treated (n = 19) and placebo (n = 20) patients and acyclovir-treated patients showed a significant reduction of exacerbations (P = 0.024). Otherwise, neurological parameters were essentially unaffected by acyclovir treatment and there were no convincing signs of reduced neurological deterioration in the acyclovir group. This study indicates that acyclovir treatment might inhibit the triggering of MS exacerbations and thus suggests that acyclovir-susceptible viruses might be involved in the pathogenesis of MS. This possibility warrants further investigation.  相似文献   
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BACKGROUND: The recently discovered arachidonic acid derivatives, isoprostanes, are increased in pathological conditions associated with oxidative stress, such as diabetes. No role has yet been described for isoprostanes during the development of diabetic nephropathy. Cell culture in high ambient glucose has been used as a model in elucidating cellular mechanisms underlying diabetic nephropathy. Among the growth factors involved in the effect of high glucose, transforming growth factor-beta (TGF-beta) has been described as playing a key role in the development of nephropathy. METHODS: Streptozotocin-induced diabetic rats were supplemented in their diet with the antioxidant vitamin E (1000 U/kg diet). Blood and urine samples were taken to determine renal function and isoprostane concentration, as determined by gas chromatography/mass spectrometry. Glomerular mesangial and endothelial cells were cultured in high ambient glucose to determine the synthesis of isoprostanes and the role of isoprostanes in high glucose-induced synthesis of TGF-beta. RESULTS: Streptozotocin-induced diabetic rats had marked increases in plasma levels and urinary excretion rates of F(2)-isoprostanes. Dietary supplementation with vitamin E normalized (plasma) and reduced (urine) isoprostane levels and, surprisingly, improved proteinuria and blood urea nitrogen (BUN) levels. High ambient glucose increased F(2)-isoprostane synthesis in glomerular endothelial and mesangial cells in culture. Incubation of glomerular cells with F(2)-isoprostanes stimulated the production of TGF-beta. CONCLUSIONS: Increased F(2)-isoprostane synthesis during diabetes appears to be responsible in part for the increase in renal TGF-beta, a well-known mediator of diabetic nephropathy.  相似文献   
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