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961.
We report a case of tinea capitis mimicking tufted hair folliculitis in a 56‐year‐old European man, who presented with a 4‐year history of pain and erythema in an area of scarring alopecia of the occipital scalp, with scales and tufts of hair emerging from individual follicles. Histological examination showed hair plugging, and a dense perifollicular infiltrate of plasma cells, lymphocytes, and neutrophils. There was widespread scarring and fibrosis. Bacterial cultures were negative for Staphylococcus aureus, but fungal cultures and periodic‐acid–Schiff stain were positive for Trichophyton tonsurans. Videodermatoscopy of the lesion showed a pattern consistent with folliculitis decalvans. Diagnosis was made on the basis of the clinical, histological, microbiological and videodermatoscopy data. After 30 days of systemic antifungal treatment, there were a substantial clinical improvement and disappearance of pain. After 5 months, a residual cicatricial area was seen with some hair tufts emerging from a single orifice.  相似文献   
962.
BACKGROUND: Head and neck non-Hodgkin's lymphomas in HIV positive patients are highly related with Epstein-Barr virus (EBV) infection. In general, viral agents can alter p53 protein levels by enhancing degradation of cellular p53 or by increasing its half-life by viral protein-p53 interaction. Moreover, it has been reported that modifications of p53 gene can modulate tumor cells' response to radio- and chemotherapy. METHODS: To assess a possible role of EBV infection, p53 protein deregulation, and p53 gene alterations in exons 5 to 8, we have studied six cases of HIV-related primary oral large B-cell lymphoma. We used in situ hybridization (ISH) for EBV-DNA and EBV-encoded nuclear RNA-1 (EBER-1), immunohistochemistry (IHC) for EBV latent membrane protein -1 (LMP-1) and p53 proteins expression, and single strand conformational polymorphism (SSCP) analysis to screen p53 gene mutations in exons 5 to 8. RESULTS: The EBV-DNA was present in all specimens, according to conventional DNA-ISH. No evidence for EBER-1 was found by ISH. The presence of EBV-DNA was correlated with the LMP-1 expression in all but one case. Moreover, p53 protein expression was negative in three cases and strongly positive in the others. However, mutational analysis of p53 gene in exons 5-8 showed no alteration. CONCLUSIONS: Our data may suggest that both EBV infection and LMP-1 expression may cause p53 loss of function even in the absence of p53 gene mutations, as assessed by SSCP. We speculate that the presence of EBV-infection and p53 protein deregulation may be responsible for radio- and chemotherapy resistance, by influencing apoptosis of cancer cells.  相似文献   
963.
964.
Celtis tala is a tree, widely distributed in Argentina. Its significance as a source of allergic sensitisation is still unclear. Our aim was to partially characterise the IgE binding proteins of C. tala pollen. Skin prick tests using C. tala pollen extract were carried out in 25 patients with respiratory allergy. Celtis tala extract elicited positive skin reactions in five patients. Sensitised patients showed increased specific IgE levels to C. tala by immunodot. Immunoblotting assay demonstrated IgE binding to proteins of 50 kDa and 55 kDa. Celtis tala pollen extract is allergenically potent requiring approximately 50 ng of self-protein for 50% inhibition of IgE binding in enzyme_linked immunosorbent assay (ELISA) inhibition, whereas no cross-inhibition was detected with other types of pollen widely distributed in Argentina (Helianthus annuus and Prosopis spp.). Thus, these results taken together indicate that proteins of 50 kDa and 55 kDa may be considered as specific allergens of C. tala pollen.  相似文献   
965.
The aim of the work is to optimise the image processing of a motion analyser. This is to improve accuracy, which is crucial for neurophysiological and rehabilitation applications. A new motion analyser, ELITE-S2, for installation on the International Space Station is described, with the focus on image processing. Important improvements are expected in the hardware of ELITE-S2 compared with ELITE and previous versions (ELITE-S and Kinelite). The core algorithm for marker recognition was based on the current ELITE version, using the cross-correlation technique. This technique was based on the matching of the expected marker shape, the so-called kernel, with image features. Optimisation of the kernel parameters was achieved using a genetic algorithm, taking into account noise rejection and accuracy. Optimisation was achieved by performing tests on six highly precise grids (with marker diameters ranging from 1.5 to 4 mm), representing all allowed marker image sizes, and on a noise image. The results of comparing the optimised kernels and the current ELITE version showed a great improvement in marker recognition accuracy, while noise rejection characteristics were preserved. An average increase in marker co-ordinate accuracy of +22% was achieved, corresponding to a mean accuracy of 0.11 pixel in comparison with 0.14 pixel, measured over all grids. An improvement of +37%, corresponding to an improvement from 0.22 pixel to 0.14 pixel, was observed over the grid with the biggest markers.  相似文献   
966.
Toll-like receptors (TLRs) are crucial players in the innate immune response to microbial invaders. The lipophilic yeast Malassezia furfur has been implicated in the triggering of scalp lesions in psoriasis. The aim of the present study was to assess the role of TLRs in the defence against M. furfur infection. The expression of the myeloid differentiation factor 88 (MyD88) gene, which is involved in the signalling pathway of many TLRs, was also analysed. In addition, a possible correlation of antimicrobial peptides of the β-defensin family to TLRs was tested. Human keratinocytes infected with M. furfur and a variety of M. furfur-positive psoriatic skin biopsies were analysed by RT-PCR, for TLRs, MyD88, human β-defensin 2 (HBD-2), HBD-3 and interleukin-8 (IL-8) mRNA expression. When keratinocytes were infected with M. furfur, an up-regulation for TLR2, MyD88, HBD-2, HBD-3 and IL-8 mRNA was demonstrated, compared to the untreated cells. The same results were obtained when psoriatic skin biopsies were analysed. The M. furfur-induced increase in HBD-2 and IL-8 gene expression is inhibited by anti-TLR2 neutralising antibodies, suggesting that TLR2 is involved in the M. furfur-induced expression of these molecules. These findings suggest the importance of TLRs in skin protection against fungi and the importance of keratinocytes as a component of innate immunity.  相似文献   
967.
968.
969.
Background:  An increasing number of youth are being diagnosed with, and treated for, bipolar disorder (BD). Controversy exists about whether youth with non-episodic irritability and symptoms of attention deficit hyperactivity disorder (ADHD) should be considered to have a developmental presentation of mania.
Method:  A selective review of the literature related to this question, along with recommendations to guide clinical assessment.
Results:  Data indicate differences between youth with episodic mania and those with non-episodic irritability in longitudinal diagnostic associations, family history, and pathophysiology. In youth with episodic mania, elation and irritability are both common during manic episodes.
Conclusions:  In diagnosing mania in youth, clinicians should focus on the presence of episodes that consist of a distinct change in mood accompanied by concurrent changes in cognition and behavior. BD should not be diagnosed in the absence of such episodes. In youth with ADHD, symptoms such as distractibility and agitation should be counted as manic symptoms only if they are markedly increased over the youth's baseline symptoms at the same time that there is a distinct change in mood and the occurrence of other associated symptoms of mania. Although different techniques for diagnosing comorbid illnesses have not been compared systematically, it appears most rational to diagnose co-occurring illnesses such as ADHD only if the symptoms of the co-occurring illness are present when the youth is euthymic.  相似文献   
970.
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