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1.
Br J Dermatol ; 167(2): 270-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22428802

RESUMO

BACKGROUND: Skin ageing is a complex process due to intrinsic chronological factors (chronoageing) and extrinsic environmental factors. The primary extrinsic factor is cumulative ultraviolet (UV) exposure, and is therefore termed photoageing. The current standards for measuring cumulative sun damage are biopsy histology and skin microtopography. However, skin biopsies are too invasive for population studies and skin replicas render only superficial skin architecture data. Reflectance confocal microscopy (RCM) is a noninvasive imaging tool that allows for in vivo imaging of the skin at quasihistological resolution. OBJECTIVES: To define and identify RCM features associated with chronological ageing and photoageing on the forearm in two age groups with different skin phototypes and to assess whether these results agree with previous findings. METHODS: We obtained RCM images of dorsal and volar nonlesional skin of the lower forearm of 75 individuals with skin Fitzpatrick phototypes I-III in two age groups (20-30 years and 50-60 years). From each participant and body site, 21 RCM features were assessed and statistically significant differences between the two age groups and different forearm sites determined. RESULTS: RCM enabled identification of changes in architecture, cell morphology and extracellular matrix (collagen) at the level of the epidermis, dermoepidermal junction and papillary dermis. Changes that were correlated with chronological ageing and which were aggravated on the UV-exposed dorsal forearm were: loss of small skin furrows resulting in wider and less intersecting furrows; irregularity of the epidermal honeycomb pattern; irregularly distributed (mottled) pigmented keratinocytes/melanocytes; irregularity of the papillary rings and/or effacement of the rete ridges; and loss of thin collagen fibres and presence of collagen clods. CONCLUSION: We have tested previously reported and new parameters for skin ageing evaluation by RCM, and identified 15 statistically significant RCM features that can be used to quantify ageing and photoageing in forearm skin noninvasively.


Assuntos
Microscopia Confocal/métodos , Envelhecimento da Pele/patologia , Pele/patologia , Adulto , Feminino , Antebraço , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Adulto Jovem
2.
G Ital Dermatol Venereol ; 143(3): 213-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18833064

RESUMO

Dermatology is perhaps the most visual specialty in medicine, making it ideally suited for modern telemedicine techniques, as has been shown in a number of recent studies investigating feasibility and reliability of teledermatology. It has generally demonstrated high levels of concordance in diagnosis and management plans compared with face-to-face consultations. Teledermatology has been also used for various purposes, including triage, diagnostic and management services, and second opinion services for primary care practitioners. It has been set up in a number of ways: 1) direct referral for primary care using images and clinical history sent to secondary care dermatology services for second opinion and for triage referrals; and 2) facilitating community-based clinics led by nurses or general practitioners. Moreover, in the last years new fields in teledermatology have grown up. Teledermoscopy is a promising area for melanoma screening as well as for diagnosis and management of equivocal pigmented skin lesions. The feasibility of mobile teledermatology and mobile teledermoscopy has been recently proved and these new facilities have the potential to become an easy applicable tool for everyone and may open the door for a new flexible triage system for detection of skin cancer in general and melanoma in particular. The implementation of virtual slide systems for teledermatopathology has allowed avoiding the limitations imposed by conventional photographs. Finally, web consultations in dermatology are a rather new tool that became available in the last years and teledermatologic services through the Internet offer many possibilities, including continuing medical education, on-line atlases and databases, and specific web application suited for teledermatology (i.e. www.telederm.org).


Assuntos
Dermatologia/métodos , Telemedicina , Dermoscopia , Humanos , Telepatologia
3.
J Med Virol ; 59(1): 14-8, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10440802

RESUMO

Hepatitis B virus (HBV) precore mutants are associated often with highly productive infection in hepatitis B surface antigen (HBsAg) carriers lacking hepatitis B e antigen (HBeAg) but positive for anti-HBe, rendering serological identification of infectious individuals unreliable. Although considered initially to be limited mostly to the Mediterranean area, more recent studies suggest a significant presence of these mutants in northern European countries. The sequence of the precore region was determined and examined for mutations from HBV isolates of 99 German chronic HBsAg carriers positive for HBV-DNA and either HBeAg (n = 15) or anti-HBe (n = 84). In addition, clinical data of individuals carrying wild-type virus and those with precore mutants were compared. HBV precore mutants were found in more than half (44/84) of all HBeAg-negative, anti-HBe-positive virus carriers. There was no difference between carriers of wild-type and precore mutant HBV in the level of viremia or in the clinical course of chronic infection. In conclusion, HBV precore mutants are common in Germany and can therefore present a diagnostic problem for serological testing. However, precore mutants do not appear to have a detrimental effect on the course of chronic HBV infection.


Assuntos
Portador Sadio/virologia , Antígenos E da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Mutação , Adulto , Idoso , DNA Viral/sangue , DNA Viral/isolamento & purificação , Feminino , Alemanha , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Antígenos E da Hepatite B/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA
4.
Z Orthop Ihre Grenzgeb ; 137(3): 214-8, 1999.
Artigo em Alemão | MEDLINE | ID: mdl-10441825

RESUMO

OBJECTIVE: The purpose of this biomechanical in-vitro-study was to compare two different PLIF-techniques with two types of implants on human lumbar spine: PLIF with threaded cages, (Bagby and Kuslich, Spinetech, Minneapolis, USA) and PLIF with the Moss-Miami-implants, (DePuy International Limited, Leeds, Great Britain). METHODS: Six cadaveric human lumbar spine segments L2-5 were explanted, frozen at -20 degrees C and thawed before preparation. They were cut in two parts by discectomie and arthrotomie L3/4, so six specimen L2/3 and six specimen L4/5 were obtained and used in a crossover-trial. Analysis included testing in a tension-torsion-machine under axial compression with 600 N, rotation (left-right) with 25 Nm and shearing forces with 250 N without preload. This was first done in the intact and then in the fused specimen. RESULTS: Stiffness before treatment was comparable in both groups irrespective of location. Posttreatment stiffness was higher with MOSS-MIAMI-implants as compared to PLIF with BAK-cages. Average relative superiority (and 95%-confidence intervall) were 1.98 (1.01-3.69) for compression, 2.30 (0.85-6.24) for rotation and 1.73 (0.78-3.84) for shearing. Statistical comparison of log posttreatment stiffness was significant for compression but not for rotation and shearing (2-sided independent crossover t-test). CONCLUSION: This biomechanical in-vitro-study demonstrates the higher initial stability of PLIF with titanium surgical mesh and posterior instrumentation when compared to PLIF with threaded cages alone.


Assuntos
Vértebras Lombares/cirurgia , Complicações Pós-Operatórias/fisiopatologia , Fusão Vertebral/instrumentação , Fenômenos Biomecânicos , Placas Ósseas , Parafusos Ósseos , Estudos Cross-Over , Humanos , Técnicas In Vitro , Vértebras Lombares/fisiopatologia , Próteses e Implantes
5.
Mund Kiefer Gesichtschir ; 1(2): 95-103, 1997 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-9410619

RESUMO

In a prospective pilot study we investigated the percentage of immunocompetent cells in the peripheral blood in 146 patients (lymphocytes, leucocytes, monocytes, T cells, B cells, NK cells, T-helper cells, T-suppressor cells, ratio T-helper/T-suppressor cells, activated T cells HLA-DR) by flow cytometry. The immunologic parameters were derived from patients with oral and oropharyngeal squamous cell carcinomas, precancerous lesions and benign tumours and from a group of heavy smokers and alcoholics. Carcinoma patients (n = 46) were compared with risk groups and a reference group consisting of patients with inflammatory disease. Within the collective of carcinoma patients we measured the immune status before and after chemo-, radio- and operative therapy. We also analysed the immune parameters in relation to clinical and histomorphological parameters (TNM status, grading). The univariate analysis of monocytes showed significant relationships between on the one hand carcinoma patients and on the other alcoholics and those with benign tumours and precancerous lesions. In precancerous lesions NK cells were significantly increased compared with alcoholics and the reference group. A significant decrease in B cells in carcinoma patients may show incipient insufficiency of the humoral immunity. The immune parameters showed a different reaction depending on therapy. After irradiation we found a significant increase of T-suppressor cytotoxic cells and decreases in B and T-helper cells. Chemotherapy showed an increase in T and T-helper cells and a decrease in B cells. Surgical therapy alone yielded an increase in B cells. The comparison of all pre- and posttherapeutic parameters showed significant changes only in activated T cells HLA-DR. We found no correlation between prognostic clinico-pathological factors and immune parameters. No changes were found in a multivariate analysis.


Assuntos
Alcoolismo/imunologia , Carcinoma de Células Escamosas/imunologia , Subpopulações de Linfócitos/imunologia , Neoplasias Bucais/imunologia , Lesões Pré-Cancerosas/imunologia , Alcoolismo/patologia , Formação de Anticorpos/imunologia , Carcinoma de Células Escamosas/patologia , Humanos , Tolerância Imunológica/imunologia , Ativação Linfocitária/imunologia , Subpopulações de Linfócitos/patologia , Neoplasias Bucais/patologia , Estadiamento de Neoplasias , Projetos Piloto , Lesões Pré-Cancerosas/patologia , Estudos Prospectivos , Fatores de Risco , Fumar/efeitos adversos , Fumar/imunologia
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