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41.
42.
The sites and numbers of submental perforator vessels were examined using a Doppler probe in 21 volunteers. The subcutaneous vascular network from each perforator was studied in three cases of dissection of upper-neck lymph nodes among the volunteers. A perforator from the submental vessels was noted in all 21 volunteers: a single perforator in 13 cases, and double perforators in eight. The main perforator, which had some subdermal branches, was located 31.8 (8.3) mm in front of the facial artery that was palpated at the mandible. Five patients who presented with skin defects on the cheek and the chin had the submental perforator flap reconstructed, excluding the platysma muscle. All flaps covered the wounds. The submental perforator flap was useful for reconstructing skin defects on the cheek and the chin, because the site of the submental perforator was stable and raising the flap was easy, and the colour and texture matches were acceptable.  相似文献   
43.
Most common scalp flaking disorders show a strong correlation with sebaceous gland (SG) activity. Early SG activity in the neonate results in microfloral colonization and cradle cap. After maternal hormonal control subsides, there is little SG activity until puberty, when the SG turns on under sex hormone control. When the SG activity increases, the present but low Malassezia population has a new food source and proliferates, resulting in the scalp itching and flaking common to greater than 50% of adults. Dry scalp flaking, dandruff, and seborrheic dermatitis are chronic scalp manifestations of similar etiology differing only in severity. The common etiology is a convergence of three factors: (1) SG secretions, (2) microfloral metabolism, and (3) individual susceptibility. Dandruff and seborrheic dermatitis (D/SD) are more than superficial stratum corneum disorders, including alteration of the epidermis with hyperproliferation, excess lipids, interdigitation of the corneal envelope, and parakeratosis. The pathogenic role of Malassezia in D/SD has recently been elucidated, and is focused on their lipid metabolism. Malassezia restricta and M. globosa require lipids. They degrade sebum, free fatty acids from triglycerides, consume specific saturated fatty acids, and leave behind the unsaturates. Penetration of the modified sebaceous secretions results in inflammation, irritation, and scalp flaking.  相似文献   
44.
We determined the presence of antibodies to the heat-shock protein hsp73 (anti-hsp73) in 57 serum samples from patients with localized scleroderma using an enzyme-linked immunosorbent assay (ELISA). In addition, 30 samples from healthy individuals, 30 from patients systemic lupus erythematosus (SLE) and 32 from patients with systemic sclerosis were assessed. IgG and/or IgM anti-hsp73 antibodies were detected in 33% (19/57) of the patients with localized scleroderma. Among the three subtypes of localized scleroderma, generalized morphoea showed the highest incidence of anti-hsp73 antibodies (40%, 6/15). IgG and/or IgM anti-hsp73 antibodies were also detected in 9/30 samples (30%) from patients with SLE and in 13/32 samples (41%) from patients with systemic sclerosis, while the samples from the healthy controls were all negative for anti-hsp73. By immunoblotting, specific binding of antibodies to hsp73 was confirmed with representative serum samples that were positive for anti-hsp73 in the ELISA. Our findings indicate that the presence of anti-hsp73 is an additional immunological abnormality in localized scleroderma.  相似文献   
45.
Localized scleroderma has been reported to be accompanied by immunological abnormalities related to B cells, but little is known about T-cell activation in this disease. In this study, serum levels of interleukin-2 (IL-2), interleukin-4 (IL-4) and interleukin-6 (IL-6), which are known to be released by activated T cells, were determined using a sensitive enzyme-linked immunosorbent assay in 48 patients with localized scleroderma and 20 with systemic sclerosis, and in 20 healthy control subjects. IL-2, IL-4 and IL-6 were detected in serum from patients with localized scleroderma but not in that from healthy controls. The presence of antihistone antibodies correlated significantly with elevated IL-4 and IL-6 levels. Decreased serum levels of IL-2, IL-4 and IL-6 paralleled improvement in cutaneous sclerosis. Frequent detection of these lymphokines in serum from patients with localized scleroderma reflects T-cell activation in this disorder.  相似文献   
46.
Systemic sclerosis (SSc) is an autoimmune systemic connective tissue disorder characterized by sclerotic change of the skin and multiple internal organs. Although the pathogenesis of this disorder is still unknown, overproduction of extracellular matrix proteins, including collagens and fibronectin, and aberrant immune activation may be involved in the mechanism. Interleukin (IL)‐1 is one of the key regulators of inflammatory response. IL‐1 is also involved in regulating connective tissue remodeling and cellular differentiation of epithelial and ectodermal cells. There are three major members of the IL‐1 family: IL‐1α, IL‐1β and IL‐1 receptor antagonist. IL‐1α was first described as a factor derived from keratinocytes that stimulates thymocyte proliferation. IL‐1α plays a crucial role in procollagen production by fibroblasts derived from patients with SSc. The present study was undertaken to investigate the serum levels of IL‐1α in patients with SSc. Serum samples were obtained from 66 Japanese patients with SSc and 19 healthy controls. Levels of serum IL‐1α were measured with a specific enzyme‐linked immunoassay kit. Mean serum levels were significantly higher in SSc patients than in those healthy control subjects. Moreover, contracture of phalanges was found at a significantly lower prevalence in SSc patients with elevated serum IL‐1α levels than those with normal levels. These results suggest that IL‐1α may play a role in the pathogenesis of SSc.  相似文献   
47.
Localized scleroderma (LSc), a connective tissue disorder restricted to the skin and subcutaneous tissue, is characterized by skin fibrosis due to an excessive deposition of types I collagen. The mechanism of such fibrosis is still unknown, but epigenetics may play some roles in the excessive collagen expression. In the present study, we investigated the mechanism of fibrosis seen in LSc, focusing on microRNA (miRNA). miRNA expression was determined by PCR array, real-time PCR, and in situ hybridization. The function of miRNA was evaluated using specific inhibitor. Immunoblotting was performed to detect α2(I) collagen protein. PCR array analysis using tissue miRNA demonstrated miR-7 level was significantly decreased in LSc skin as well as keloid tissue compared to normal skin in vivo. In situ hybridization also showed miR-7 expression in dermal fibroblasts was decreased in LSc dermis. The transfection of specific inhibitor for miR-7 into cultured normal dermal fibroblasts resulted in the up-regulation of α2(I) collagen protein in vitro. Also, the serum levels of miR-7 were significantly decreased in LSc patients compared with healthy controls, but serum miR-29a levels not. Systemic or local down-regulation of miR-7 may contribute to the pathogenesis of LSc via the overexpression of α2(I) collagen, and serum miR-7 may be useful as a disease marker. Investigation of the regulatory mechanisms of LSc by miRNA may lead to new treatments by the transfection into the lesional skin of this disease.  相似文献   
48.

Background

Malassezia yeasts are normal flora of the skin found in 75~98% of healthy subjects. The accurate identification of the Malassezia species is important for determining the pathogenesis of the Malassezia yeasts with regard to various skin diseases such as Malassezia folliculitis, seborrheic dermatitis, and atopic dermatitis.

Objective

This research was conducted to determine a more accurate and rapid molecular test for the identification and classification of Malassezia yeasts.

Methods

We compared the accuracy and efficacy of restriction fragment length polymorphism (RFLP) and the nested polymerase chain reaction (PCR) for the identification of Malassezia yeasts.

Results

Although both methods demonstrated rapid and reliable results with regard to identification, the nested PCR method was faster. However, 7 different Malassezia species (1.2%) were identified by the nested PCR compared to the RFLP method.

Conclusion

Our results show that RFLP method was relatively more accurate and reliable for the detection of various Malassezia species compared to the nested PCR. But, in the aspect of simplicity and time saving, the latter method has its own advantages. In addition, the 26S rDNA, which was targeted in this study, contains highly conserved base sequences and enough sequence variation for inter-species identification of Malassezia yeasts.  相似文献   
49.
Abstract:  Localized scleroderma is a connective tissue disorder that is limited to the skin and subcutaneous tissue. Macrophages have been reported to be particularly activated in patients with skin disease including systemic sclerosis and are potentially important sources for fibrosis-inducing cytokines, such as transforming growth factor β. To clarify the features of immunohistochemical characterization of the immune cell infiltrates in localized scleroderma focusing on macrophages, skin biopsy specimens were analysed by immunohistochemistry. The number of cells stained with monoclonal antibodies, CD68, CD163 and CD204, was calculated. An evident macrophage infiltrate and increased number of alternatively activated macrophages (M2 macrophages) in their fibrotic areas were observed along with their severity of inflammation. This study revealed that alternatively activated macrophages (M2 macrophages) may be a potential source of fibrosis-inducing cytokines in localized scleroderma, and may play a crucial role in the pathogenesis of localized scleroderma.  相似文献   
50.
Rationale:Veno-occlusive disease (VOD) is characterized by painful hepatomegaly, ascites, weight gain, and jaundice with nonthrombotic, fibrous obliteration of the centrilobular hepatic veins. VOD after liver transplantation is a rare complication, with an incidence of approximately 2%; however, it can be life-threatening in severe cases. The precise etiology and mechanism of VOD after liver transplantation remains unclear. Acute cellular rejection, antibody-mediated rejection, and treatment with tacrolimus or azathioprine may be associated with the development of VOD after liver transplantation. Additionally, the optimal treatment of VOD after liver transplantation has not yet been established and focuses on supportive care. Defibrotide is an anti-ischemic and antithrombotic drug with no systemic anticoagulant effects. Moreover, only a few reports have investigated the use of defibrotide for VOD after liver transplantation, which has shown promising results.Patient concerns:A 39-year-old woman with primary biliary cholangitis underwent living-donor liver transplantation at our center. She experienced right upper quadrant pain with increased ascites, pleural effusion, and weight gain on postoperative day 14.Diagnoses:Imaging and pathological tests showed no evidence of rejection or vessel complications. VOD was diagnosed clinically based on the findings of weight gain, ascites, jaundice, and pathological biopsy.Interventions:Defibrotid, 25 mg/kg/day, was administered intravenously for 21 days.Outcomes:She showed complete clinical resolution of the VOD.Lessons:Herein, we report a case of successful defibrotide treatment of VOD after living-donor liver transplantation.  相似文献   
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