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71.
Recently, we reported that Src homology 2 domain-containing protein tyrosine phosphatase substrate 1 (SHPS-1) plays an important role in the migration of Langerhans cells (LC). Here, we show that SHPS-1 is involved in the maturation of LC. Immunofluorescence analysis on epidermal sheets for I-A or CD86 revealed that LC maturation induced by 2,4-dinitro-1-fluorobenzene (DNFB) or by TNF-alpha was inhibited by pretreatment with an anti-SHPS-1 monoclonal antibody (mAb) or with CD47-Fc fusion protein, a ligand for SHPS-1. Further, FACS analysis demonstrated that I-A(+) LC that had emigrated from skin explants expressed CD80 or CD86, whereas CD47-Fc protein reduced CD80(high+) or CD86(high+) cells. CD47-Fc protein also reduced the up-regulation of surface CD80 or CD86 by LC remaining in the skin explants. In SHPS-1 mutant mice, we observed that the up-regulation of surface CD86 and CCR7 by LC induced by DNFB as well as that of surface CD80 and CD86 by LC in skin explants was attenuated. Finally, contact hypersensitivity (CHS) response was suppressed in SHPS-1 mutant mice and in wild-type mice treated with an anti-SHPS-1 mAb. These observations indicate that SHPS-1 plays an important role in the maturation of LC ex vivo and in vivo, and that SHPS-1-CD47 interaction may negatively regulate CHS.  相似文献   
72.
Two new dimeric sterols, manadosterols A (1) and B (2), were isolated from the marine sponge Lissodendryx fibrosa collected in Indonesia. The two compounds are comprised of two sulfonated sterol cores connected through the respective side chains. Manadosterols A (1) and B (2) inhibited the Ubc13-Uev1A interaction with IC(50) values of 0.09 and 0.13 μM, respectively. They are the second and third natural compounds showing inhibitory activities against the Ubc13-Uev1A interaction and are more potent than leucettamol A (IC(50), 106 μM), the first such inhibitor, isolated from another marine sponge.  相似文献   
73.
AIM: To evaluate the safety and clinical application of high-intensity focused ultrasound (HIFU) therapy for unresectable pancreatic cancer (PC).METHODS: Thirty PC patients (16 cases in stage III and 14 cases in stage IV) with visualized pancreatic tumors were admitted for HIFU therapy as an optional local therapy in addition to systemic chemotherapy or chemoradiotherapy. Informed consent was obtained. This study began at the end of 2008 and was approved by the ethics committee of our hospital [Institutional Review Board (IRB): 890]. The HIFU device used was the FEP-BY02 (Yuande Bio-Medical Engineering, Beijing, China).RESULTS: The mean tumor size after HIFU therapy changed to 30.9 ± 1.7 mm from 31.7 ± 1.7 mm at pre-therapy. There were no significant changes in tumor size, mean number of treatment sessions (2.7 ± 0.1 mm), or mean total treatment time (2.4 ± 0.1 h). The rate of symptom relief effect was 66.7%. The effectiveness of primary lesion treatment was as follows: complete response, 0; partial response, 4; stable disease, 22; progressive disease, 4. Treatment after HIFU therapy included 2 operations, 24 chemotherapy treatments, and 4 best supportive care treatments. Adverse events occurred in 10% of cases, namely pseudocyst formation in 2 cases and mild pancreatitis development in 1. However, no severe adverse events occurred in this study.CONCLUSION: We suggest that HIFU therapy is safe and has the potential to be a new method of combination therapy for PC.  相似文献   
74.
Cathinone-derived designer drugs have recently grown to be popular as drugs of abuse. 3,4-Dimethylmethcathinone (DMMC) has recently been abused as one of the alternatives to controlled cathinones. In the present study, DMMC and its major metabolites, 3,4-dimethylcathinone (DMC), 1-(3,4-dimethylphenyl)-2-methylaminopropan-1-ol (β-OH-DMMC, diastereomers), and 2-amino-1-(3,4-dimethylphenyl)propan-1-ol (β-OH-DMC, diastereomers), have been identified and quantified in a DMMC user’s urine by gas chromatography–mass spectrometry and liquid chromatography–tandem mass spectrometry using newly synthesized authentic standards. Other putative metabolites including oxidative metabolites of the xylyl group and conjugated metabolites have also been detected in urine. The identified and putative phase I metabolites indicated that the metabolic pathways of DMMC include its reduction of the ketone group to the corresponding alcohols, N-demethylation to the primary amine, oxidation of the xylyl group to the corresponding alcohol and carboxylate forms, and combination of these steps. Concentrations of the identified metabolites were found to increase slightly after enzymatic hydrolysis, suggesting that these compounds are partially metabolized to the respective conjugates.  相似文献   
75.
We report two rare cases of recurrent, multiple eccrine spiradenoma. Both cases presented with extensive lesions comprised of multiple red papules of various sizes and a soft blue-red nodule. The first case was a 30-year-old woman. Her lesions followed a linear arrangement on her chin, and extended down the right side of the neck with spontaneous pain. The second case was a 57-year-old woman with tumors in a localized group on the left occipital region without pain. A search of the literature revealed only 15 reported cases of linear/zosteriform/nevoid multiple eccrine spiradenoma. Both cases were treated by surgical excision. Most of the red papules displayed typical histological features including two cell types: large clear cells with low-density cytoplasm; and small dark cells with high-density cytoplasm. The large soft tumors exhibited a variable histological appearance. In the first case, the cystic tumors displayed an homogeneous structure comprised of eosinophilic material. In the second case, the cystic tumors included abundant interstitial tissue.  相似文献   
76.
Tumor necrosis factor (TNF)-α is known to play a pivotal role in the pathogenesis of psoriasis. TNF-α has been shown to act directly on keratinocytes, thereby inducing the production of various kinds of chemokines, which contributes to the infiltration of leucocytes into the psoriatic lesions. Recent studies have shown that both interleukin (IL)-17 and IL-27 are increased in psoriatic lesional tissue. However, the interactions between TNF-α, IL-17 and IL-27 in chemokine production by keratinocytes have not been fully elucidated. Here, we examined in human keratinocytes how TNF-α, IL-17 and IL-27 affect production of chemokines that are involved in the pathogenesis of psoriasis. We found that IL-17 and IL-27 exert opposite effects on TNF-α-mediated chemokine production. This suggests that lesional balance of IL-17 and IL-27 is involved in the recruitment of T cells, natural killer cells, neutrophils, monocytes or dendritic cells, thereby affecting inflammation in skin diseases.  相似文献   
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78.
CD47 is a membrane-associated glycoprotein that suppresses the function of immune cells. We previously reported that Langerhans cells (LCs) express Src homology 2 domain-containing protein tyrosine phosphatase substrate 1 (SHPS-1), a ligand for CD47, which plays an important role in the regulation of their motility. In this study, we show that LCs also express CD47, and that ligation of CD47 with SHPS-1-Fc fusion protein in vivo diminishes the development of the contact hypersensitivity response. We further demonstrate that CD47 engagement affects immune functions of LCs. CD47 engagement in vivo significantly inhibits the emigration of LCs from the epidermis into draining lymph nodes following treatment with haptens and tumor necrosis factor-alpha. The emigration of dendritic cells from skin explants into the medium and the chemotaxis of murine XS52 dendritic cells were significantly reduced by treatment with SHPS-1-Fc or an anti-CD47 mAb. Under explant culture system, SHPS-1-Fc treatment suppressed the expression of CD80 and CD86 of LCs. These effects on LCs and contact hypersensitivity response of CD47 ligation were reversed by treatment with pertussis toxin. These results suggest that the ligation of CD47 inhibits the migration of LCs and the expression of B7 costimulatory molecules, which results in inhibition of the contact hypersensitivity response.  相似文献   
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