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101.
Langerhans cells (LCs) are epidermal dendritic cells with incompletely understood origins that associate with hair follicles for unknown reasons. Here we show that in response to external stress, mouse hair follicles recruited Gr-1(hi) monocyte-derived precursors of LCs whose epidermal entry was dependent on the chemokine receptors CCR2 and CCR6, whereas the chemokine receptor CCR8 inhibited the recruitment of LCs. Distinct hair-follicle regions had differences in their expression of ligands for CCR2 and CCR6. The isthmus expressed the chemokine CCL2; the infundibulum expressed the chemokine CCL20; and keratinocytes in the bulge produced the chemokine CCL8, which is the ligand for CCR8. Thus, distinct hair-follicle keratinocyte subpopulations promoted or inhibited repopulation with LCs via differences in chemokine production, a feature also noted in humans. Pre-LCs failed to enter hairless skin in mice or humans, which establishes hair follicles as portals for LCs.  相似文献   
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The iliac crest bone grafting (ICBG) technique for lumbar posterolateral fusion surgery is widely used; however, donor site problems such as pain and sensory disturbance have been reported. Local bone is available for fusion surgery, but its reliability as a graft has not been fully reported. In the current study, we examined single-level instrumented posterolateral fusion with a local bone graft versus an ICBG in a prospective randomized study. Eighty-two patients diagnosed with L4 degenerated spondylolisthesis were divided into two groups at random. Forty-two patients underwent instrumented posterolateral fusion with a local bone graft (L4–L5 level), and 40 patients underwent instrumented posterolateral fusion with an ICBG (L4–L5 level). Rate and duration of bone union, visual analog scale (VAS) score, Japanese orthopedic association score (JOAS), Oswestry Disability Index (ODI), and complications were evaluated before and 2 years after therapy. VAS score, JOAS, and ODI were not significantly different between the two groups before and after surgery (P > 0.05). Rate and average duration of bone union were 90% and 8.5 months in the local bone graft group, and 85% and 7.7 months in the ICBG group, but without significant difference (P > 0.05). Prolonged surgical time and complications such as donor site pain (8 patients) and sensory disturbance (6 patients) were observed in the ICBG group. If single-level posterolateral fusion was performed, local bone graft technique has the same bone union rate compared with ICBG, requires less surgical time, and has fewer complications.  相似文献   
105.

Purpose  

We aimed to reveal the difference in contrast enhancement of the abdominal organs and major vessels on dynamic contrast-enhanced magnetic resonance imaging (DCM-MRI) using gadoxetic sodium (Gd-EOB-DTPA) and gadopentetate dimeglumine (Gd-DTPA) in the same patients.  相似文献   
106.
Quantification of arthritis is helpful for investigating pain mechanisms of arthritis and for developing new drugs. We assessed and identified a feasible parameter for quantification of rat arthritis using a novel gait analyzing system. Knee-joint injection with small doses of lambda-carrageenan decreased swing time ratio (STR, swing time of the non-treated hindlimb/swing time of the lambda-carrageenan-injected hindlimb) in a dose-dependent manner. Intraperitoneal treatment with indomethacin restored the decreased STR dose-dependently. The arthritis could not be accurately quantified by swing time and swelling, common indices of arthritis. These results show that STR is a sensitive, reliable parameter for quantification of arthritis.  相似文献   
107.
Valk E  Leung R  Kang H  Kaneko K  Rudd CE  Schneider H 《Immunity》2006,25(5):807-821
The costimulatory molecule CTLA-4 is a potent downregulator of T cell responses. Although localized mostly in intracellular compartments, little is understood regarding the mechanism that regulates its transport to the cell surface. In this study, we demonstrated that the adaptor TRIM (T cell receptor-interacting molecule) bound to CTLA-4 in the trans Golgi network (TGN) and promoted transport of CTLA-4 to the surface of T cells. Increased TRIM expression augmented surface CTLA-4 expression, and pulse-chase analysis showed a more rapid transport of CTLA-4 to the cell surface. A reduction of TRIM expression by small hairpin RNAs reduced the expression of surface CTLA-4. This resulted in a more localized pattern of CTLA-4 in the TGN. Altered CTLA-4 expression by TRIM was accompanied by corresponding changes in coreceptor-mediated effects on cytokine production and proliferation. Our findings identify a role for TRIM as a chaperone in regulating CTLA-4 expression and function by enhancing CTLA-4 transport to the surface of T cells.  相似文献   
108.
BACKGROUNDS: Although long-term treatment with beta-blockers has been shown to improve morbidity and mortality in dilated cardiomyopathy (DCM), patient responses are heterogeneous. METHODS: To establish the appropriate indication for the initiation of beta-blocker therapy, we retrospectively analyzed 38 DCM patients treated with beta-blockers (metoprolol or carvedilol) and examined differences in baseline profiles between patients who could continue the therapy (responders) and those who could not (non-responders). RESULTS: In 13 non-responders, the duration from onset of symptoms to beta-blocker initiation was longer (p < 0.05), systolic blood pressure was lower (p < 0.001), serum sodium concentration was lower (p < 0.05), left ventricular posterior wall thickness was thinner (p < 0.05), left ventricular end-diastolic pressure was higher (p < 0.05) and left ventricular wall stress was lower (p < 0.05) than in 25 responders. In 19 patients receiving carvedilol, 5 non-responders showed higher levels of human atrial natriuretic peptide (p < 0.05) and brain natriuretic peptide (p < 0.01) than 13 responders. Discriminant analysis with a linear discriminant function showed the following equation predicted response to beta-blocker therapy: h = 0.004 x systolic blood pressure - 0.002 x brain natriuretic peptide + 0.667 (R2 = 0.67, p < 0.001). The probability of predicting the response was 94.1% with h > or = 0.5. CONCLUSION: We conclude that h > or = 0.5 is the appropriate indication for the initiation of beta-blocker therapy in DCM.  相似文献   
109.
Aim: Japanese nurses have increasingly experienced “burnout” in the past several years. Studies on Japanese nurses are required in order to explore how to prevent nursing burnout. The objectives of this report were to: (i) introduce the concept, definition, and measurement of burnout; (ii) look at an overview of the prevalence, possible causes, and consequences of burnout among Japanese nurses; and (iii) explore how to prevent burnout among nurses. Methods: The authors and co‐researchers have been studying burnout among Japanese workers for more than 15 years. Therefore, previously performed studies were reviewed and summarized. Results: In Japan, approximately 36% of human services professionals, such as nurses, were burned out compared to 18% of civil servants, and 12% of company employees. It was quite obvious that nurses are prone to burnout. The possible causes and consequences of burnout among Japanese nurses were reviewed. Excessive workloads and interpersonal conflict in the workplace were possible causes of burnout among Japanese nurses. The consequences of nurse burnout are potentially very serious, including medical accidents/errors. Issues to prevent nursing burnout were then reviewed. Enhancement of cognitive coping skills for female nurses and problem‐solving skills for male nurses could contribute to prevention of burnout in nurses. Conclusion: The authors' previous study revealed that the new model of the organizational context of burnout developed by Leiter and Maslach could be applied to Japanese. Further examination is needed. This report supports the call to scale up burnout prevention strategy for Japanese nurses.  相似文献   
110.
Patients with indwelling catheters at home are more likely to receive home‐visit nursing care. However, the condition of patients with indwelling catheters among those receiving home‐visit nursing care, as well as the actual status of catheter management practised by visiting nurses, has not been studied. The aim of this study was to study the condition of long‐term indwelling urinary catheter users receiving home‐visit nursing care and the status of catheter management by visiting nurses. Thirty visiting nurses with experience in home‐visit nursing care for patients with long‐term indwelling catheters participated in this study. The questionnaire covered (1) attributes of visiting nurses, (2) the condition of indwelling catheter users, and (3) the state of implementation of catheter management by visiting nurses and difficulties experienced. It was found that patients receiving home‐visit nursing care had used indwelling catheters for a prolonged period for both disease management and other reasons, and they developed various abnormal symptoms and complications such as urinary tract infection. A high percentage of visiting nurses implemented all the items of observation, practice, guidance and cooperation in catheter management. Items of catheter management that caused difficulty for visiting nurses included detection of urinary tract infection or other complications, catheter insertion, obtaining catheter replacement supplies, encouraging ingestion of water and cooperation with physicians. This study concludes by throwing light on the condition of long‐term indwelling urinary catheter users receiving home‐visit nursing care, and the status of catheter management by visiting nurses.  相似文献   
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