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921.
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Gardam S Turner VM Anderton H Limaye S Basten A Koentgen F Vaux DL Silke J Brink R 《Blood》2011,117(15):4041-4051
B cells require signals delivered through B-cell activating factor of the TNF family receptor (BAFF-R) and CD40 to survive and produce antibody responses in vivo. In vitro data indicate that these signals are controlled by the homologous RING finger proteins cIAP1 and cIAP2, in collaboration with TRAF2 and TRAF3. There is also mounting evidence that all 4 of these signaling molecules can act as tumor suppressors in human B-lineage malignancies. However, it has not been possible to identify the roles of cIAP1 and cIAP2 in controlling B-cell physiology because of the absence of an appropriate in vivo model. Here we describe a unique genetically modified mouse in which the linked cIap1 and cIap2 genes can be independently inactivated. Deletion of cIAP1 plus cIAP2 (but not either protein alone) rendered primary B cells independent of BAFF-R for their survival and led to their uncontrolled accumulation in vivo. B cells deficient in cIAP1 and cIAP2 were also incapable of forming germinal centers, a key step in antibody-mediated immunity. These data define a fundamental role for cIAP1/cIAP2 in regulating B-cell survival and responsiveness, show this requires direct binding to TRAF2, and suggest how mutations of TRAF2, TRAF3, and cIAP1/cIAP2 contribute to B-lineage malignancies, such as multiple myeloma. 相似文献
924.
Nakasone H Binh PN Yamazaki R Tanaka Y Sakamoto K Ashizawa M Sato M Terasako K Kimura S Kikuchi M Kako S Okuda S Oshima K Tanihara A Nishida J Abe Y Kanda Y 《Blood》2011,117(12):3469-3472
Recently, a growing body of evidence has suggested that adiponectin, which is secreted by adipose tissues, plays a critical role in obesity-related and autoimmune diseases. We compared the concentrations of adiponectin among 26 normal subjects and 34 allogeneic stem cell transplantation recipients. The concentrations of adiponectin were significantly higher in recipients with chronic graft-versus-host disease (cGVHD) than those in subjects without cGVHD (21.7 ± 11.0 vs 9.1 ± 6.1 μg/mL in females, P < .001; and 10.1 ± 6.8 vs 4.3 ± 2.9 μg/mL in males, P = .003). Multivariate analysis revealed that a higher concentration of adiponectin was associated with female sex (β-coefficient 8.2, P < .0001) and the severity of cGVHD (β-coefficient 6.6, 12.7, and 15.6, P < .01, each for mild, moderate, and severe cGVHD, respectively). In addition, adiponectin levels increased as cGVHD progressed, decreased as cGVHD improved, and did not change with stable cGVHD. In conclusion, adiponectin was associated with the severity of cGVHD and might play a role in the pathophysiology of cGVHD. 相似文献
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926.
HIV testing uptake at 3 antenatal clinics in Johannesburg was 53% (1 333/2 502) during 4 months when lay counsellors were unpaid, which was lower than the 7 months when payment was provided (79%; 3 705/4 722; p<0.001), and a subsequent 12-month period (86%, 11 877/13 767; p<0.001) when counsellors were paid. Consistent remuneration of lay counsellors could markedly improve services for preventing mother-to-child HIV transmission. 相似文献
927.
A pressure ulcer is a medical complication that arises in persons with decreased mobility and/or sensation. Deep pressure ulcers starting at the bone-muscle interface are the most dangerous, as they can cause extensive damage before showing any signs at the skin surface. We previously proposed a novel intervention called intermittent electrical stimulation (IES) for the prevention of deep tissue injury (DTI). In this study, we tested the effects of four paradigms of IES and one conventional pressure relief paradigm in preventing the formation of deep pressure ulcers in rats. Loading equivalent to 18, 28, or 38% of the body weight (BW) of each rat was applied to the triceps surae muscle in one hind limb. Treatment groups received IES every 10 min for either (i) 5 or 10 s with moderate or maximal contraction, or (ii) complete pressure removal every 10 min for 10 s (conventional pressure relief). The results showed that conventional pressure relief, emulating a wheelchair push-up every 10 min, was inadequate for the prevention of DTI. In contrast, all IES paradigms were equally effective in significantly reducing the extent of deep muscle damage caused by 28 or 38% BW pressure application. These findings suggest that, in conjunction with existing techniques, IES may be an effective intervention for the prophylactic prevention of DTI. 相似文献
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Bernard T. Haylen Vivian Yang Dzung Vu Kelly Tse 《International urogynecology journal》2011,22(1):69-75