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Melasma represents a pigmentary disorder that is difficult to treat. This study aims to broadly review the use of ablative lasers (Er:YAG and CO2) in the treatment of melasma, presenting the level of evidence of studies published to date. A total of 75 patients were enrolled in four case series studies (n=39), one controlled clinical trial (n=6) and one randomized controlled clinical trial (n=30). Studies on the Er:YAG laser showed better results with the use of short square-shaped pulses, which determined low rates of post-inflammatory hyperpigmentation and long-lasting maintenance of results. Likewise, studies on the CO2 laser proved the benefits of short pulse duration along with low-density energy. Post-treatment maintenance with the use of antipigmenting creams was necessary and effective to sustain long-term results. Ablative lasers may represent another useful and effective tool against melasma. Postinflammatory hyperpigmentation and difficulty in sustaining long-term results still represent the main limitations to a broader use of ablative lasers. Based on actual evidence, the use of this technology should be restricted to patients with recalcitrant disease. Further studies will help establish optimal laser parameters and treatment regimens.  相似文献   
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Homocysteine is a sulfur-containing amino acid derived from methionine metabolism. When plasma homocysteine levels exceed 10–15 μM, there is a condition known as hyperhomocysteinemia, which occur as a result of an inborn error of methionine metabolism or by non-genetic causes. Mild hyperhomocysteinemia is considered a risk factor for development of neurodegenerative diseases. The objective of the present study was to evaluate whether acetylsalicylic acid has neuroprotective role on the effect of homocysteine on inflammatory, oxidative/nitrative stress, and morphological parameters in cerebral cortex of rats subjected to chronic mild hyperhomocysteinemia. Wistar male rats received homocysteine (0.03 μmol/g of body weight) by subcutaneous injections twice a day and acetylsalicylic acid (25 mg/Kg of body weight) by intraperitoneal injections once a day from the 30th to the 60th postpartum day. Control rats received vehicle solution in the same volume. Results showed that rats subjected to chronic mild hyperhomocysteinemia significantly increased IL-1β, IL-6, and acetylcholinesterase activity and reduced nitrite levels. Homocysteine decreased catalase activity and immunocontent and superoxide dismutase activity, caused protein and DNA damage, and altered neurons ultrastructure. Acetylsalicylic acid totally prevented the effect of homocysteine on acetylcholinesterase activity and catalase activity and immunocontent, as well as the ultrastructural changes, and partially prevented alterations on IL-1β levels, superoxide dismutase activity, sulfhydryl content, and comet assay. Acetylsalicylic acid per se increased DNA damage index. In summary, our findings showed that chronic chemically induced model of mild hyperhomocysteinemia altered some parameters and acetylsalicylic acid administration seemed to be neuroprotective, at least in part, on neurotoxicity of homocysteine.  相似文献   
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Idiopathic Atrophoderma of Pasini and Pierini (IAPP) is a rare, exclusively cutaneous disease. It is more frequent in females, with incidence peak in the second and third decades of life. The etiopathogenesis remains unknown. IAPP most commonly affects the back, abdomen and proximal regions of the limbs. Lesions may be rounded, oval or circular; single or multiple. The evolution is variable and the course is initially progressive. Collagen changes such as atrophy, thinning, condensation and sclerosis may be observed in the papillary dermis. This paper describes a case of Idiopathic Atrophoderma of Pasini and Pierini with histopathologic findings.  相似文献   
65.
Prostatic artery embolization requires a refined technique to achieve good imaging and clinical success. The PErFecTED (Proximal Embolization First, Then Embolize Distal) technique has produced greater prostate ischemia and infarction than previously described methods with clinical improvement of lower urinary symptoms and lower recurrence rates. The microcatheter should cross any collateral branch to the bladder, rectum, corpus cavernosum, gonad, or penis and be placed distally into the prostatic artery before its branching to the central gland and peripheral zone. This technique allows better distribution of embolic material in the intraprostatic arteries and reduces risk of spasm or thrombus. Because benign prostatic hyperplasia develops primarily in the periurethral region of the prostate, the urethral group of arteries should be embolized first. Subsequent distal investigation and embolization completes occlusion and stasis of blood flow to the prostatic parenchyma. Since we added the second step to the PErFecTED technique, we have observed infarcts in all patients submitted to prostatic artery embolization.  相似文献   
66.
Social context plays a significant role in adolescent identity development, particularly for youth lacking traditional systems of support. Using ecological and symbolic interactionism perspectives, this study qualitatively explored the psychosocial identity development of Black gay, bisexual, or transgendered youth participating in the House Ball Community (HBC). The HBC is a diverse network of family-like structures called ‘houses’, as well as a glamorous social outlet via pageant-like ‘balls’ in which participants compete. A series of focus groups were conducted with youth and leaders from the HBC (n?=?37; age range?=?17–24). Via cross-case and comparative analyses, specific motivating factors related to entry into and continued involvement in the community were identified. Factors related to entry into the community included lack of safe spaces, opportunities for acceptance, means of subsistence, and allure of the scene. Factors related to continued involvement included resilience and coping skills development, sexual identity acceptance and pride, prevalence of risky behaviour, and risk of exploitation. Discussion of these factors provides insight on how self-constructed, supplementary social contexts may provide both unique supports and risks to members, allowing for more focused and well-informed interventions and policies to enhance healthy development in such communities while mitigating risk.  相似文献   
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Several studies have suggested that rheumatoid arthritis (RA) is uncommon in rural sub-Saharan Africa. The aim of this study is to determine the potential differences between patients with RA living in rural areas and those living in urban areas. We performed a cross-sectional study from June 2006 to May 2009. We included all patients with RA (1987 ACR criteria) seen at the Rheumatology Unit of the Le Dantec Teaching Hospital, Dakar, Senegal. We compared the main socio-demographic and clinical characteristics of patients living in rural areas to those living in urban areas. We included 180 patients in our study, of whom, 143 (79.4?%) lived in urban areas and 37 (20.6?%) in rural areas. The median age was 44?years [range 34–55] in patients from rural areas vs. 41?years [range 30–53] in patients from urban areas, without any statistical significance (p?=?0.24). Patients under the age of 60 mostly lived in urban areas (p?=?0.03). The extra-articular manifestations were significantly more frequent in patients living in rural areas (p?=?0.02). There was no statistical significance when comparing the delay in diagnosis, number of swollen joints, disease activity, hand deformities, and concentration of autoantibodies (RF and ACPA) in both populations. The percentage of patients seen from the rural areas of Senegal is low (20.6?%) compared to those seen from the urban areas. The number of extra-articular manifestations is the main difference between patients living in rural and urban areas. The role played by environmental factors seems important. Further incidence studies are needed.  相似文献   
70.
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