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Hélio Amante Miot

Bio: Hélio Amante Miot is an academic researcher from Sao Paulo State University. The author has contributed to research in topics: Medicine & Melasma. The author has an hindex of 30, co-authored 337 publications receiving 3729 citations. Previous affiliations of Hélio Amante Miot include University of São Paulo & State University of Campinas.


Papers
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Journal ArticleDOI
TL;DR: In this article, a proper sample planning depends on basic knowledge of the study statistics and deep knowledge of a problem under investigation, in order to combine the statistical significance of the tests with the clinical meaning of the results.
Abstract: dimension and also the sampling technique (collection/selection) of the elements of the study. It is essential in the elaboration of the project, and problems with such planning may compromise the final data analysis and interpretation of its results. A proper sample planning depends on basic knowledge of the study statistics and deep knowledge of the problem under investigation, in order to combine the statistical significance of the tests with the clinical meaning of the results 1,3,4 . Most biostatistical tests assume that the study sample is probabilistically representative of the population. Some samples of convenience, e.g. like choosing consecutive patients of a specific outpatient clinic, may not properly rep resent all the study population. The investigator should be alert to possible selection biases resulting from the availability of patients in consecutive sampling, because increasing sample size would not correct the effect of biased samples. In addition, strategies of non-probability stratified sampling, by using sample quotas, complex sampling (conglomerates, multi-levels), voluntary response, saturation of variables,

245 citations

Journal ArticleDOI
TL;DR: The authors discuss the main clinical and epidemiological aspects of melasma, a chronic acquired hypermelanosis of the skin characterized by irregular brown macules symmetrically distributed on sun-exposed areas of the body, particularly on the face.
Abstract: Melasma is a chronic acquired hypermelanosis of the skin, characterized by irregular brown macules symmetrically distributed on sun-exposed areas of the body, particularly on the face. It is a common cause of demand for dermatological care that affects mainly women (especially during the menacme), and more pigmented phenotypes (Fitzpatrick skin types III-V). Due to its frequent facial involvement, the disease has an impact on the quality of life of patients. Its pathogeny is not yet completely understood, although there are some known triggering factors such as sun exposure, pregnancy, sexual hormones, inflammatory processes of the skin, use of cosmetics, steroids, and photosensitizing drugs. There is also a clear genetic predisposition, since over 40% of patients reported having relatives affected with the disease. In this manuscript, the authors discuss the main clinical and epidemiological aspects of melasma.

199 citations

Journal ArticleDOI
TL;DR: A large number of patients with chronic hypermelanosis of sun‐exposed areas are diagnosed with atypical central giant cell granuloma, which is a leading cause of death in people with these patients.
Abstract: Background Melasma is a common acquired chronic hypermelanosis of sun-exposed areas which significantly impacts quality of life. There are few epidemiological studies in medical literature concerning these patients. Objective Characterize clinical and epidemiological data on Brazilian female patients with melasma. Methods A semi-structured questionnaire was administered to melasma patients treated at a dermatology clinic between 2005 and 2010. Association between variables was performed by multivariate regression models. Results We assessed 302 patients; intermediate skin phototypes III (34.4%) and IV (38.4%) were prevalent. Mean disease onset age was 27.5 ± 7.8 years and familiar occurrence of melasma was identified in 56.3%. The most commonly reported trigger factors were pregnancy (36.4%), contraceptive pills (16.2%) and intense sun exposure (27.2%). Preferred facial topographies were zygomatic (83.8%), labial superior (51.3%) and frontal (49.7%). Pregnancy induced melasma has been associated to early disease (OR = 0.86) and number of pregnancies (OR = 1.39). Childbearing was correlated to melasma extension. Older disease onset age was associated to darker skin phototypes. Co-occurrence of facial topographies supported clinical classification as centrofacial and peripheral melasma. Conclusion This population was characterized by: a high prevalence in adult females, intermediate skin phototypes, disease precipitation by hormonal stimulus and familiar genetic influence.

135 citations

Journal ArticleDOI
TL;DR: The authors present a review of the epidemiology of basal cell carcinoma, finding that between 30% and 75% of the sporadic cases are associated with patched hedgehog gene mutation, but other genetic changes are also described.
Abstract: Basal cell carcinoma is the most common malignant neoplasm in humans and its incidence has increased over the last decades. Its high frequency significantly burdens the health system, making the disease a public health issue. Despite the low mortality rates and the rare occurrence of metastases, the tumor may be locally invasive and relapse after treatment, causing significant morbidity. Exposure to ultraviolet radiation is the main environmental risk factor associated with its cause. However, other elements of risk are described, such as light skin phototypes, advanced age, family history of skin carcinoma, light eyes and blond hair, freckles in childhood and immunosuppression. Behavioral aspects such as occupational sun exposure, rural labor and sunburns at a young age also play a role. Between 30% and 75% of the sporadic cases are associated with patched hedgehog gene mutation, but other genetic changes are also described. The tumor is commonly found in concomitance with skin lesions related to chronic sun exposure, such as actinic keratoses, solar lentigines and facial telangiectasia. The prevention of basal cell carcinoma is based on the knowledge of risk factors, early diagnosis and treatment, as well as on the adoption of specific measures, particularly in susceptible populations. The authors present a review of the epidemiology of basal cell carcinoma.

125 citations

Journal ArticleDOI
TL;DR: The main clinical, epidemiological and pathophysiological aspects of female pattern hair loss are discussed, with characteristic clinical, dermoscopic and histological patterns.
Abstract: Female Pattern Hair Loss or female androgenetic alopecia is the main cause of hair loss in adult women and has a major impact on patients' quality of life. It evolves from the progressive miniaturization of follicles that lead to a subsequent decrease of the hair density, leading to a non-scarring diffuse alopecia, with characteristic clinical, dermoscopic and histological patterns. In spite of the high frequency of the disease and the relevance of its psychological impact, its pathogenesis is not yet fully understood, being influenced by genetic, hormonal and environmental factors. In addition, response to treatment is variable. In this article, authors discuss the main clinical, epidemiological and pathophysiological aspects of female pattern hair loss.

121 citations


Cited by
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Journal ArticleDOI
21 Jul 1979-BMJ
TL;DR: It is suggested that if assessment of overdoses were left to house doctors there would be an increase in admissions to psychiatric units, outpatients, and referrals to social services, but for house doctors to assess overdoses would provide no economy for the psychiatric or social services.
Abstract: admission. This proportion could already be greater in some parts of the country and may increase if referrals of cases of self-poisoning increase faster than the facilities for their assessment and management. The provision of social work and psychiatric expertise in casualty departments may be one means of preventing unnecessary medical admissions without risk to the patients. Dr Blake's and Dr Bramble's figures do not demonstrate, however, that any advantage would attach to medical teams taking over assessment from psychiatrists except that, by implication, assessments would be completed sooner by staff working on the ward full time. What the figures actually suggest is that if assessment of overdoses were left to house doctors there would be an increase in admissions to psychiatric units (by 19°U), outpatients (by 5O°'), and referrals to social services (by 140o). So for house doctors to assess overdoses would provide no economy for the psychiatric or social services. The study does not tell us what the consequences would have been for the six patients who the psychiatrists would have admitted but to whom the house doctors would have offered outpatient appointments. E J SALTER

4,497 citations

DOI
05 Nov 2009
TL;DR: 结节病易误诊,据王洪武等~([1])收集国内18篇关于此第一印象中拟诊 结核5例,为此应引起临床对本 病诊
Abstract: 结节病易误诊,据王洪武等~([1])收集国内18篇关于此病误诊的文献,误诊率高达63.2%,当然有误诊就会有误治,如孙永昌等~([2])报道26例结节病在影像学检查诊断的第一印象中拟诊结核5例,其中就有2例完成规范的抗结核治疗,为此应引起临床对本病诊治的重视。

1,821 citations

Journal ArticleDOI
TL;DR: Issues from grading of acne to the topical and systemic management of the disease are reviewed and suggestions on use are provided based on available evidence.
Abstract: Acne is one of the most common disorders treated by dermatologists and other health care providers. While it most often affects adolescents, it is not uncommon in adults and can also be seen in children. This evidence-based guideline addresses important clinical questions that arise in its management. Issues from grading of acne to the topical and systemic management of the disease are reviewed. Suggestions on use are provided based on available evidence.

928 citations

Journal Article
TL;DR: In this paper, the authors explore the current knowledge about distinct signalling cascades resulting from self TLR activation and highlight the involvement of endogenous TLR activators in disease and highlight how specifically targeting DAMPs may yield therapies that do not globally suppress the immune system.
Abstract: Damage-associated molecular patterns (DAMPs) include endogenous intracellular molecules released by activated or necrotic cells and extracellular matrix (ECM) molecules that are upregulated upon injury or degraded following tissue damage. DAMPs are vital danger signals that alert our immune system to tissue damage upon both infectious and sterile insult. DAMP activation of Toll-like receptors (TLRs) induces inflammatory gene expression to mediate tissue repair. However, DAMPs have also been implicated in diseases where excessive inflammation plays a key role in pathogenesis, including rheumatoid arthritis (RA), cancer, and atherosclerosis. TLR activation by DAMPs may initiate positive feedback loops where increasing tissue damage perpetuates pro-inflammatory responses leading to chronic inflammation. Here we explore the current knowledge about distinct signalling cascades resulting from self TLR activation. We also discuss the involvement of endogenous TLR activators in disease and highlight how specifically targeting DAMPs may yield therapies that do not globally suppress the immune system.

724 citations

Journal ArticleDOI
TL;DR: In this article, the authors present a comprehensive coverage of those skin diseases in which histopathology plays an important role in diagnosis, and present a clinicopathologic classification of cutaneous disease while incorporating a primer on pattern-algorithm diagnosis.
Abstract: Remains your authoritative source for comprehensive coverage of those skin diseases in which histopathology plays an important role in diagnosis. This edition maintains the proven, clinicopathologic classification of cutaneous disease while incorporating a “primer” on pattern-algorithm diagnosis. More than 1,800 full-color illustrations, including photomicrographs and clinical photographs, help you visualize and make the most of the clinical diagnostic process.

703 citations