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101.
NKG2D blockade prevents autoimmune diabetes in NOD mice   总被引:19,自引:0,他引:19  
NKG2D is an activating receptor on CD8(+) T cells and NK cells that has been implicated in immunity against tumors and microbial pathogens. Here we show that RAE-1 is present in prediabetic pancreas islets of NOD mice and that autoreactive CD8(+) T cells infiltrating the pancreas express NKG2D. Treatment with a nondepleting anti-NKG2D monoclonal antibody (mAb) during the prediabetic stage completely prevented disease by impairing the expansion and function of autoreactive CD8(+) T cells. These findings demonstrate that NKG2D is essential for disease progression and suggest a new therapeutic target for autoimmune type I diabetes.  相似文献   
102.
Experiments were performed to study the effects of agents that elevate endogenous cyclic AMP levels on the progression of a reverse passive Arthus reaction in the pleural cavity of rats. Three hours after the onset of the reaction a marked reduction in histamine release was observed which correlated well with increases in cellular cyclic AMP concentration. The results at 6 hr suggested a relationship between cyclic AMP and leucocyte PGE, the latter being reduced dramatically both in the cells and in the fluid exudate by agents that elevate cyclic AMP. It was concluded that cyclic AMP may play an important regulatory role in vivo in the release of inflammatory mediators from leucocytes.  相似文献   
103.

To determine whether pregnant women receiving the Mothers and Babies group–based intervention exhibited greater depressive symptom reductions and fewer new cases of major depression than women receiving usual community-based services, and to examine whether groups run by paraprofessional home visitors and mental health professionals yielded similar depressive symptom reductions and prevention of major depression. Using a cluster-randomized design, 37 home visiting programs were randomized to usual home visiting, Mothers and Babies delivered via home visiting paraprofessionals, or Mothers and Babies delivered via mental health professionals. Baseline assessments were conducted prenatally with follow-up extending to 24 weeks postpartum. Eligibility criteria were ≥ 16 years old, ≤ 33 gestation upon referral, and Spanish/English speaking. Depressive symptoms at 24 weeks postpartum was the primary outcome. Eight hundred seventy-four women were enrolled. Neither intervention arm was superior to usual care in decreasing depressive symptoms across the sample (p = 0.401 home visiting paraprofessional vs. control; p = 0.430 mental health professional vs. control). Post hoc analyses suggest a positive intervention effect for women exhibiting mild depressive symptoms at baseline. We have evidence of non-inferiority, as the model-estimated mean difference in depressive symptoms between intervention arms (0.01 points, 95% CI: −0.79, 0.78) did not surpass our pre-specified margin of non-inferiority of two points. Although we did not find statistically significant differences between intervention and control arms, non-inferiority analyses found paraprofessional home visitors generated similar reductions in depressive symptoms as mental health professionals. Additionally, Mothers and Babies appears to reduce depressive symptoms among women with mild depressive symptoms when delivered by mental health professionals. This trial is registered on ClinicalTrials.gov (initial post: December 1, 2016; identifier: NCT02979444).

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Despite the increasing attention paid to the role of social forces in determining health, most physicians finish their training ill-prepared to address these issues. The authors describe their efforts to fill that training gap for internal medicine residents at Oregon Health and Science University through a community-based social medicine curriculum, designed in 2006 in conjunction with community partners at Central City Concern (CCC), an organization addressing homelessness, poverty, and addiction in downtown Portland, Oregon. The challenge was to develop a curriculum that would (1) fit within the scheduling constraints of an established categorical internal medicine residency program, (2) give all internal medicine residents a chance to better understand how social forces affect health, and (3) help show how they, as health professionals, might intervene to improve health and health care. The authors maintain that by developing this curriculum with community partners--who took the lead in deciding what residents should learn about their community and how they should learn it--the residency program is providing a relatively brief but extremely rich opportunity for residents to engage the personal, social, and health-related issues experienced by clients served by CCC.The authors first provide a brief overview of the curriculum and describe how the principles and practices of community-based participatory research were used in its development. They then discuss the challenges involved in teaching medical residents about social determinants of health, how their academic-community partnership approaches those challenges, and the recently established methods of evaluating the curriculum.  相似文献   
107.
Primary DNA damage sensing in mammalian global genome nucleotide excision repair (GG-NER) is performed by the xeroderma pigmentosum group C (XPC)/HR23B protein complex. HR23B and HR23A are human homologs of the yeast ubiquitin-domain repair factor RAD23, the function of which is unknown. Knockout mice revealed that mHR23A and mHR23B have a fully redundant role in NER, and a partially redundant function in embryonic development. Inactivation of both genes causes embryonic lethality, but appeared still compatible with cellular viability. Analysis of mHR23A/B double-mutant cells showed that HR23 proteins function in NER by governing XPC stability via partial protection against proteasomal degradation. Interestingly, NER-type DNA damage further stabilizes XPC and thereby enhances repair. These findings resolve the primary function of RAD23 in repair and reveal a novel DNA-damage-dependent regulation mechanism of DNA repair in eukaryotes, which may be part of a more global damage-response circuitry.  相似文献   
108.
Autosomal dominant (de novo) mutations in PBX1 are known to cause congenital abnormalities of the kidney and urinary tract (CAKUT), with or without extra‐renal abnormalities. Using trio exome sequencing, we identified a PBX1 p.(Arg107Trp) mutation in a deceased one‐day‐old neonate presenting with CAKUT, asplenia, and severe bilateral diaphragmatic thinning and eventration. Further investigation by droplet digital PCR revealed that the mutation had occurred post‐zygotically in the father, with different variant allele frequencies of the mosaic PBX1 mutation in blood (10%) and sperm (20%). Interestingly, the father had subclinical hydronephrosis in childhood. With an expected recurrence risk of one in five, chorionic villus sampling and prenatal diagnosis for the PBX1 mutation identified recurrence in a subsequent pregnancy. The family opted to continue the pregnancy and the second affected sibling was stillborn at 35 weeks, presenting with similar severe bilateral diaphragmatic eventration, microsplenia, and complete sex reversal (46, XY female). This study highlights the importance of follow‐up studies for presumed de novo and low‐level mosaic variants and broadens the phenotypic spectrum of developmental abnormalities caused by PBX1 mutations.  相似文献   
109.
Cell line PER-278 was established from a bone marrow sample of a 10-year-old boy diagnosed with pre-B acute lymphoblastic leukemia (ALL). PER-278 cells show the pre-B phenotype, express cytoplasmic Ig, and exhibit two translocations: t(1;19)(q23;p13) and t(1;9)(q23;p13). Assessment of the immunoglobulin rearrangements confirmed the clonal origin of cell line PER-278, and comparison with the patients's leukemic cells showed an identical pattern: loci involved at the breakpoint on chromosome 1 code for the oncogene SKI and for the Fc receptor II and on chromosome 19 for the insulin receptor. The t(1;19) may contribute to the malignant transformation in leukemic cells of pre-B phenotype.  相似文献   
110.
Summary Peak torque, work, mean power and electromyographic (EMG) activity were recorded for each of 150 repeated isokinetic maximal shoulder flexions (45°–90°) in 23 healthy females. From the EMG signals of trapezius, deltoid, infraspinatus and biceps brachii the mean power frequency and the signal amplitude were determined in real time. The mechanical output showed a steep decrease during the first 40 contractions, followed by a plateau maintained until the end. In all muscles, except the biceps brachii, significant decreases in mean power frequency occurred during the first 40 contractions, showing a tendency to stabilize around the same absolute frequency value. Signal amplitude increased in the trapezius, the deltoid and the infraspinatus, but was constant in the biceps brachii. For some individuals rather high EMG activity was recorded in the muscles during the time the arm was supposed to be passively extended to the starting position, and this was found to be associated with lower strength and endurance levels. Longitudinal analyses showed that the mean power frequencies correlated better than the signal amplitudes with the three mechanical variables. The results suggest that the initial steep decrease in mechanical performance and mean power frequency is caused by fatiguing of type 2 motor units.  相似文献   
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