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Background  

Sporadic and sometimes contradictory studies have indicated changes in satellite cell behaviour associated with the progressive nature of human Duchenne muscular dystrophy (DMD). Satellite cell proliferation and number are reportedly altered in DMD and the mdx mouse model. We recently found that satellite cells in MSVski transgenic mice, a muscle hypertrophy model showing progressive muscle degeneration, display a severe ageing-related differentiation defect in vitro. We tested the hypothesis that similar changes contribute to the gradual loss of muscle function with age in mdx and PMP22 mice, a model of human motor and sensory neuropathy type 1A (HMSN1A).  相似文献   
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Weight is recognized as an important factor in determining an individuals risk of osteoporosis. However, little is known about whether weight or weight change influences bone loss around the time of the menopause, and the relationship with energy intake and physical activity level remains largely undefined. Healthy premenopausal women (1,064 selected from a random population of 5,119 women aged 45–54 years at baseline) each had bone mineral density (BMD), weight and height measurements, and completed a food frequency and physical activity questionnaire. Of the original participants, 907 women (85.2%) returned 6.3 ± 0.6 years later for repeat BMD measurements, and 896 women completed the questionnaires. Bone loss at the hip (FN) and spine (LS) occurred before the menopause. Weight change rather than weight was associated with FN BMD loss (r=0.102, p=0.002), but weight at follow-up was associated with LS BMD change (r=0.105, p=0.002). Although an increase in physical activity level (PAL) appeared to be beneficial for FN BMD in women who were heavy weight gainers, PAL was associated with increased LS BMD loss in women who lost weight. For current HRT users, neither weight nor weight change was associated with change in BMD. Postmenopausal women not taking HRT should be made aware that low body weight or losing weight during this particularly vulnerable period may worsen bone loss.  相似文献   
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Indolent CD8+ cutaneous lymphoid proliferation represents a recently described entity among cutaneous T‐cell lymphomas that typically presents with solitary skin lesions on the face or at acral sites and usually follows an indolent clinical course. Histopathologically, this entity is characterized by a dense dermal infiltrate of non‐epidermotropic, small‐ to medium‐sized pleomorphic CD8+ T‐cells of the non‐activated cytotoxic phenotype showing a clear‐cut grenz zone and a low proliferation index. Distinction from otherwise aggressive T‐cell lymphomas bearing a cytotoxic CD8+ phenotype is fundamental. We herein present an unusual case of indolent CD8+ cutaneous lymphoid proliferation presenting in bilateral symmetrical distribution on both feet and lacking the otherwise described grenz zone. Our case widens the spectrum of possible clinical and histomorphological variations of this entity. Taking into account the distinctive and unique clinical and microscopic features of all hitherto published cases of indolent CD8+ cutaneous lymphoid proliferation we suppose that this lymphoma subtype has to be included as a new and distinct entity in the World Health Organisation (WHO)‐/European Organisation for Research and Treatment of Cancer (EORTC)‐classification of cutaneous lymphomas.  相似文献   
96.
OBJECTIVE--To examine biopsy specimens of tissue immediately adjacent to anogenital (AG) warts which had been treated with either cryotherapy plus subcutaneous interferon (IFN) alpha 2a or cryotherapy alone, for histological features of (a) human papilloma virus (HPV) infection (b) localised cellular immune responses, to further characterise any cellular immune infiltrates with tissue immunocytochemistry, and to relate any histological, immunocytochemical findings to the treatment response of nearby AG warts. DESIGN--A randomised placebo controlled observer blind study. SETTING--Genitourinary Medicine clinic, Department of Immunopathology, Royal Victoria Hospital, Belfast, N. Ireland. SUBJECTS--Thirty patients with AG warts; 16 treated with IFN alpha 2a plus cryotherapy, and 14 treated with cryotherapy alone. OUTCOME MEASURES--(1) Light microscopic features associated with HPV infection and local cellular immune responses. (2) Indirect immunofluorescence detection of the following cell surface markers: HLA DR, alpha one antitrypsin, CD1, CD3, CD4, CD8, CD22. (3) Clinical response of AG warts to treatment. RESULTS--In pre-treatment biopsies only non specific indicators of HPV infection (acanthosis, 29/30 biopsies, and hyperkeratosis, 7/30 biopsies) were seen on light microscopy. Mononuclear cells were seen both throughout the upper dermis and centred around dermal blood vessels in 19/30 (63.3%) biopsies, and infiltrating into the epidermis in 12/30 (40%) biopsies. On indirect immunofluorescence CD3, CD8, CD4 antigen was detected on the surface of cells throughout the upper dermis in 24/29 (82.7%), 15/29 (51.7%), and 3/29 (10.3%), of biopsy specimens respectively. CD3 antigen, CD8 antigen and CD4 antigen was detected on the surface of cells infiltrating into the epidermis in 18/29 (62%), 7/29 (24.1%), and 6/29 (20.7%) of biopsy specimens respectively. CD1 antigen was seen on the surface of dendritic cells throughout the epidermis in all specimens; CD1 positive cells infiltrated into the upper dermis in 5/29 (17.2%). HLA DR was detected on the surface of dendritic cells throughout the epidermis in 22/29 (75.9%) of specimens, and on the surface of cells scattered both diffusely throughout the upper dermis and centred around dermal blood vessels in all specimens. Alpha one antitrypsin (A1AT) antigen was seen on the surface of cells in the upper dermis in 6/29 (20.7%) of biopsy specimens; no cells expressing CD22 surface antigen were seen. The nature of this local cellular immune response was not altered by treatment of nearby warts with either cryotherapy alone or cryotherapy plus systemic IFN alpha 2a, or related to the therapeutic outcome of these warts. CONCLUSIONS--(1) No convincing histological evidence of HPV infection was seen in epithelium surrounding AG warts. (2) A predominantly T cell-mediated immune response (the target of which is uncertain) was seen in this perilesional epithelium. (3) In the dosage regimens used in this study, treatment of AG warts with either systemic IFN alpha 2a plus cryotherapy or cryotherapy alone did not appear to augment localised cellular immune responses (against any presumed subclinical HPV infection) in epithelium surrounding AG warts.  相似文献   
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OBJECTIVE: To determine whether the combination of systemically administered interferon alpha-2a and ablative surgery for the treatment of genital and/or perianal warts produces a 30% or greater improvement in lasting response rate compared with a control group receiving a combination of placebo and ablative therapy. DESIGN: Randomised, triple-blind, placebo-controlled trial using 1 or 3 MIU of interferon alpha-2a or placebo administered subcutaneously three times weekly for 10 weeks in combination with ablative surgery. SETTING: International, multicentre study in 10 genitourinary medicine clinics. PATIENTS: Two hundred and fifty patients with anogenital warts. MAIN OUTCOME MEASURES: Lasting response at week 38. RESULTS: Standard efficacy analysis at week 38 showed a lasting response in 51% (35/68) of 3 MIU interferon-treated patients, 48% (30/63) of 1 MIU interferon-treated patients and 43% (29/67) of placebo-treated patients. CONCLUSIONS: With the doses and regime described, treatment with interferon alpha-2a in combination with ablative therapy is not significantly superior in the treatment of anogenital warts than placebo and ablative therapy.  相似文献   
100.
OBJECTIVES--The primary objective was to determine if six weeks treatment with subcutaneous interferon alpha-2a (IFN) and podophyllin 25% W/V administered twice per week, preceded by IFN alpha-2a three times weekly for one week showed a greater complete response rate in patients with primary condylomata acuminata when assessed at week 10 than treatment with podophyllin and placebo injections in the same schedule. The secondary objective was to compare recurrence rates in complete responders at six months in the two treatment groups. DESIGN--Randomised, double-blind parallel group study. SETTING--Multicentre study in six genitourinary clinics within the U.K. PATIENTS--One hundred and twenty-four patients with primary anogenital warts. MAIN OUTCOME MEASURES--Complete response rate at week 10, and recurrence rate at week 26 in complete responders. RESULTS--At week 10 analysis of the efficacy population showed complete response in 36% (15/42 patients) of IFN-treated group and 26% (11/43 patients) in the placebo group (no significant difference). Analysis of the safety population at week 26 showed persistence of the complete response in 57% (8/14 patients) of the IFN-treated group and 80% (12/15 patients) of the placebo group (no significant difference). Adverse effects were more common in IFN-treated patients, involved particularly application site reaction and malaise but were generally mild. CONCLUSIONS--At the dose and with the regime described treatment with IFN alpha-2a in combination with podophyllin is no more effective in the treatment of primary anogenital warts than podophyllin alone and is associated with more adverse events.  相似文献   
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