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Coffin-Lowry syndrome (CLS) is an X-linked disorder associated with mental retardation, distinctive facies and hands, hypotonia, and skeletal abnormalities. The syndrome results from mutations in the RSK2 gene located in Xp22.2. Although the syndrome has been elucidated clinically, few, if any, studies have focused on the cognitive deficits of the affected males or carrier females. The subjects of the present study were selected from two African-American families who have the same missense mutation (C340T) in RSK2. The subjects included six affected males, seven carrier females, three normal males and three non-carrier (normal) females. Normal family members served as contrast/comparison cohorts to control for socio-economic, sociocultural and genetic variables which would impinge on intellectual abilities. Analysis of cognitive function, as measured by the Stanford-Binet Intelligence Scale, 4th edn, demonstrated a distinct hierarchy of abilities from normal to carrier to affected patients. The mean composite IQs of the cohorts were 90.8, 65.0 and 43.2 for normal, carrier and affected individuals, respectively. These findings lend support to the clinical concept of negative intellectual effects in carriers of certain X-linked mental retardation conditions. X-inactivation studies showed that carrier females had mild to significant skewing. Normal females in the family did not demonstrate skewing. The correlation coefficient between IQ and X-inactivation status among carriers was not significant.  相似文献   
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We showed that the paraphenylenediamine (PPD) poisoning caused myocarditis but there is no data on the echocardiographic features. We report a case of myocarditis induced by PPD poisoning with echographic data. After ingestion of 5 g of PPD, a 18-year-old woman was admitted to the hospital with asphyxia and rhabdomyolysis. An electrocardiogram showed ventricular extrasystoles and negative T waves. The serum concentration of CK was 28,020 UI l(-1) (iso-enzyme MB = 840 UI l(-1)). A transthoracic echocardiography showed significant left and right ventricular hypokinesis (shortening fraction = 20% and left ventricular ejection fraction = 35%) and a left ventricular apical thrombus. Anticoagulation treatment with heparin was initiated. A follow-up echocardiogram performed on the 15th day showed normalization of ventricular function and disappearance of the thrombus. No embolic event was noted. Echocardiography is indicated in the myocarditis induced by PPD poisoning to prove the ventricular function as well as the presence of a thrombus.  相似文献   
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目的:建立大鼠的骨质疏松性椎体骨折模型,探讨骨折愈合程度与X射线、骨结构和力学性能的相互关系,以期能为临床治疗提供科学的指导和理论依据。方法:实验于2005-07/2006-07在解放军兰州军区总医院骨研所完成。实验动物:选择雌性SPF级8个月龄SD大鼠54只。实验分组:采用随机数字法将大鼠分为2组:骨质疏松组和对照组,每组27只。实验干预:骨质疏松组经双背侧手术切除卵巢,对照组行伪手术。术后3个月,所有动物麻醉下,采用L5椎体手术开窗刮除术区内松质骨方法建立人工椎体骨折模型。实验评估:于术后1,2,4,6,8,12周观察两组大鼠腰椎影像学、骨组织切片组织学与受累椎体力学性能。结果:54只SD大鼠全部进入结果分析。①影像学观察:术后两组X射线片示L5椎体有一骨折缺损透光区。对照组在术后6周时原透光区与周围骨质无明显差别,而骨质疏松组原透光区仍清晰可见,于8周时无明显差别。②组织学观察:两组软骨细胞在骨愈合1周时出现,形成软骨岛,但骨质疏松组软骨细胞每高倍视野数量明显少于对照组,另外,软骨细胞改建成成熟骨细胞,骨小梁形成数量,胶原纤维排列与对照组比较有显著性差异。③力学性能:在骨质愈合6~12周,L5椎体的最大载荷、弹性模量、最大应力明显低于同期对照组,差异有显著性意义(P<0.05)。结论:骨质疏松性椎体骨折SD大鼠模型,符合动物模型标准,可用于研究新骨形成与正常骨质结构关系,观察骨质疏松性椎体骨折愈合机制,并证明骨质疏松性松质骨骨折修复过程中,骨折愈合质量降低。  相似文献   
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Background

We examined the association of alcohol use disorders (AUD) with adherence to and health-related quality of life (HRQOL) outcomes of antiretroviral treatment (ART) for HIV/AIDS patients.

Methods

A cross-sectional multi-site survey was conducted in 468 drug users and 648 non-drug users (age: 35.4 ± 7.0 years; 63.8% male) in 3 epicentres of Vietnam. AUD, ART adherence, and HRQOL were measured using the Alcohol Use Disorders Identification Test - Consumption (AUDIT-C), the self-reported Visual Analogue Scale (VAS), and the World Health Organization Quality of Life instrument (WHOQOL-HIV BREF).

Results

35.0% of drug users were hazardous drinkers, compared to 25.9% of non-drug users. 22.3% of drug users engaged in binge drinking, and 25.9% reported suboptimal ART adherence. Adjusting for propensity scores of AUD, patients who had either at-risk or binge drinking behaviour were about twice as likely to be treatment non-adherent as those who did not have AUD. Hazardous drinkers reported small to medium decrements in the Performance, Physical, Social, Spirituality, and Environment quality of life domains. Binge drinkers had a slightly higher score in Social dimension.

Conclusion

AUD is prevalent and negatively affecting adherence to and HRQOL outcomes of ART services in injection-driven HIV epidemics. Screening and intervention are recommended for AUD, especially during the stable periods of ART. Other social and psychological interventions might also enhance patients’ responses to and outcomes of ART in Vietnam.  相似文献   
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T-cell hybridomas are highly metastatic, and their in vitro invasiveness correlates with metastatic capacity. Invasion is blocked by pertussis toxin (PT), which adenosine diphosphate (ADP)-ribosylates G1-proteins, and we have provided evidence that the PT-sensitive signal stimulates leukocyte function-associated antigen-1 (LFA-1)-mediated adhesion required for invasion. PT pretreatment of TAM2D2 T-cell hybridoma cells reduced metastasis, but only to a limited extent. In the present study, we have transfected the cDNA of the PT ADP- ribosyltransferase S1 subunit into TAM2D2 cells to abrogate G1-protein function permanently. We report here a substantial reduction in the metastatic capacity of two transfectants, S05 and S09, in which 88% and 95% of the G1-proteins was ADP-ribosylated. Two-thirds of the mice injected with S09 cells were tumor-free. Metastasis to the liver was almost completely prevented and less metastases were formed in the spleen and kidneys. Metastasis formation by S05 cells in liver and spleen was much reduced, but in lymph nodes and peritoneal tissues, metastases occurred with a frequency similar to that of controls. We conclude that G1-proteins play an important role in T-cell hybridoma metastasis. We propose that the reduction in metastasis is due to diminished entry of tumor cells from the blood into tissues.  相似文献   
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