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1.
Studies have shown a high correlation between measurements of bone mineral density (BMD) obtained on differentdual-energy X-ray absorptiometry machines. Challenger osteodensitometers (Diagnostic Medical System [DMS],Montpellier, France) are becoming widely used but little is known about their clinical performance. The aim of this study was to compare BMD measurements and the resulting patient classification based on T-scores obtained on a DMS Challenger device to those obtained on Hologic 4500A (Bedford, MA) device. Fifty-three volunteers were studied.The BMD of the spine and of the hip were simultaneously measured on both densitometers. BMD values obtained on the Challenger were significantly higher than those obtained with the Hologic QDR4500 (p<0.001). The correlations coefficients between the Hologic QDR4500 and the DMS Challenger measured BMDs were r=0.70 at the femoral neck, r=0.70 at the trochanter, and r=0.83 at the spine (p<0.001). Among the 35 postmenopausal women, there was discordance in the WHO T-score-based classification in 28 subjects (80%) at the spine, 18 subjects (52%) at the femoral neck, and 14 subjects (42%) at the trochanter. The intermachine agreement was low: The kappa score was -0.10 at the spine, 0.2 at the femoral neck, and 0.3 at the trochanter. In conclusion, this study cautions against the use of non established densitometers that leads to underdiagnosis of patients and, subsequently, to inappropriate treatment strategies.  相似文献   
2.
Synovial sarcoma demonstrates epithelial differentiation, either by light microscopy (biphasic synovial sarcoma) or by immunohistochemical/ultrastructural methods only (monophasic) and poorly differentiated synovial sarcoma. Although the glands of synovial sarcoma are known to have tight junction-like structures, far less is known about junction formation in the spindled component of synovial sarcomas. Additionally, it is unknown whether the tight junctions of synovial sarcoma are normally constituted. The tight junction is a multiprotein complex consisting of numerous proteins that include ZO-1, claudin-1 and occludin. A total of 35 cases of synovial sarcoma (13 biphasic, 14 monophasic and eight poorly differentiated) were immunostained for ZO-1, claudin-1 and occludin using commercially available antibodies, heat-induced epitope retrieval and standard avidin-biotin technique. When available, corresponding electron micrographs were reviewed. For five cases, the presence of either an SYT-SSX1 (three cases) or SYT-SSX2 (two cases) gene fusion was known. Positive cases showed particulate membrane staining. The glands of biphasic synovial sarcomas expressed ZO-1 (13/13), claudin-1 (12/13) and occludin (11/13) in a manner identical to normal glandular epithelia, at the apical portion of the lateral membrane. The spindle cells of biphasic synovial sarcomas showed abnormal circumferential membranous expression of ZO-1 (12/13), claudin-1 (6/13) and occludin (3/13). Monophasic synovial sarcomas expressed ZO-1 in a circumferential pattern (13/14) but less often claudin-1 (4/14) or occludin (3/14). Poorly differentiated synovial sarcomas expressed ZO-1 (8/8) and claudin-1 (6/8) but only rarely occludin (2/8). By electron microscopy, recognizable tight junctions were seen only in glands. No correlation was seen between histologic subtype or fusion type and expression of tight junction proteins. We conclude that the glands of biphasic synovial sarcomas show well-organized, true epithelial tight junctions. In contrast, the spindled cells of all synovial sarcomas show significant abnormalities in the expression and localization of tight junction proteins, suggesting partial and/or aberrant epithelial differentiation.  相似文献   
3.
It has been speculated that exposure to the chronic stress of racism contributes to the high rates of hypertension among African Americans. Social support may buffer the effects of stress on cardiovascular (CV) health by attenuating stress-induced CV responses that have been linked to hypertension. In this study we investigated the effects of racism and social support on CV reactivity in African American women. Participants showed greater increases in CV and emotional responses while responding and listening to racist provocation. Augmented blood pressure (BP) persisted through recovery following racial stress. Participants receiving no support showed the greatest increases in anger during racist provocation. No significant effects were seen for support on CV reactivity. These results provide some of the first evidence that interactive confrontation with racism elicits significant increases in CV reactivity and emotional distress. Furthermore, individuals receiving less support may be at greater risk for the potentially health-damaging effects of racial stress. These findings may have significant implications for the health of African Americans.  相似文献   
4.
Haplotypic association of DDAH1 with susceptibility to pre-eclampsia   总被引:3,自引:0,他引:3  
Association between pre-eclampsia (PEE1) and the dimethylarginine dimethylaminohydrolase (DDAH) 1 and 2 genes, which play a role in the regulation of nitric oxide synthesis and release, was studied. In a case-control study design single nucleotide polymorphisms (SNPs) were determined at eight sites in the DDAH1 gene and at one site (Pro231Pro) in the DDAH2 gene from 132 women with pre-eclampsia and 112 healthy controls. Three SNPs in the DDAH1 gene were associated with pre-eclampsia, showing complete linkage disequilibrium with each other, but none of the associations in the allele or genotype data reached statistical significance in either of the genes after the correction for multiple testing. Haplotype frequencies were estimated using a population based on a maximum likelihood method (EM algorithm). Four common DDAH1 haplotypes were present and a significant association of haplotypes H2 and H3 with pre-eclampsia (P=0.03) was found. The risk of pre-eclampsia was greatest in individuals (odds ratio: 3.93; 95% confidence interval: 1.54-9.99) who had two copies of the high-risk haplotypes (H2 or H3). The observed haplotypic association provides the first evidence of the importance of DDAH1 polymorphisms in pre-eclampsia susceptibility.  相似文献   
5.
IFN-alpha and IFN-beta: a link between immune memory and chronic inflammation   总被引:11,自引:0,他引:11  
The majority of expanded T cells generated during an immune response are cleared by apoptosis. Prevention of death in some activated T cells enables the persistence of a memory T-cell pool. Here, observations that IFN-alpha and IFN-beta inhibit activated T-cell apoptosis are described. Although this enables memory T cells to persist without antigen, excessive IFN-alpha or IFN-gamma secretion might lead to chronic inflammation.  相似文献   
6.
7.
Queensland is home to the largest diaspora of Māori and Pasifika peoples in Australia. They form an understudied population concerning experiences and challenges of food insecurity. This community co-designed research aims to explore the conceptualization of household food security by Māori and Pasifika peoples living in south-east Queensland. Participatory action research and talanoa were used to collect and analyse forty interviews with leaders representing 22 Māori and Pasifika cultural identities in south-east Queensland. Eight key themes emerged that conceptualise food security as an integral part of the culture and holistic health. These themes included: spirituality, identity, hospitality and reciprocity, stigma and shame, expectations and obligations, physical and mental health and barriers and solutions. Addressing food insecurity for collectivist cultures such as Māori and Pasifika peoples requires embracing food sovereignty approaches for improved food security through the co-design of practical solutions that impact social determinants and strengthen existing networks to produce and distribute affordable and nutritious food.  相似文献   
8.
9.
Introduction: Tunisia is experiencing a double burden of morbidity, characterized by the explosion of cardiovascular diseases and their risk factors including arterial Hypertension. The objective of this study, based on the HSHS cohort (Hammam Sousse Sahloul Heart Study), was to determine the prevalence of hypertension in the general population and to identify its predisposing factors. Methods: HSHS is a cardiovascular health promotion initiative in the city of Hammam Sousse (Tunisia). The study was conducted via a random sample of households, using the WHO PEV technique, made up of 33 clusters, of 33 households each. All people aged 20 and over, included, benefited from a questionnaire, a physical examination and a biological assessment. The Systolic Blood Pressure (SBP) and the Diastolic Blood Pressure (DBP) were measured from the average of the last two measurements, by an OMRON type tensiometer, of suitable width. These prevalences were adjusted according to sex and age group, by their weighting coefficients in the general population, and they were accompanied by their 95% CIs. Binary logistic regression was conducted to identify independent factors associated with hypertension. Results: The study population was composed of 481 men (33.4%) and 960 women (66.6%), with an average age of 49.6±16.35 years in males (M) and 46.6±16.18 in females (F). In addition to the family history of hypertension, the sufficient weekly consumption of vegetables and fruits was low (M: 32.4%, F: 24.9%). The adjusted rate of hypertension in the adult study population was 32.5%, 95%CI[31.9-33.1] (M: 36.4%, 95%CI[35, 5-37.3]; F: 28.4%; 95% CI[27.6-29.2]), reaching in the age group of 60 years and above: M: 74.6% (95%CI[66.9-82.3], F: 82.7% (95%CI[73.8-83.6]) Multivariate analysis identified five independent factors significantly associated with hypertension: male sex (ORa=1.55 [1.18-2.03]), age over 40 years (ORa=6.54[4.70-9.11]), low level of schooling (ORa=1.80 [1.36-2.38]), low physical activity (ORa=1.42[1.07-1.88]) and high socio-economic level (ORa=1 .84 [1.30-2.63]). Conclusion: The HSHS study confirmed the high prevalence of hypertension, and the extent of its low detection and control. Hence the need for a universal approach to health promotion, oriented towards the general population, piloted by its local organizations, based on the adoption of a healthy lifestyle, and centered on physical activity.  相似文献   
10.
This study presents the conversion of bovine horn powder (BHP) as an available and low-cost waste material to a value-added highly recyclable catalyst. This green catalyst was prepared through the immobilization of BHP, as a natural keratin resource, on the magnetic Fe3O4 nanoparticles. The successful preparation of the catalyst was fully investigated using Fourier transform infrared, X-ray diffraction, and energy-dispersive X-ray spectroscopies as well as field emission scanning electron microscopy, vibrating sample magnetometry, and thermogravimetry. The catalytic efficiency of the prepared magnetic organocatalyst was evaluated in the synthesis of a large series of amide derivatives through the solvent-free transamidation reaction of different amides and amines with yields of 75–96%.

The conversion of bovine horn powder as an available and low-cost waste material to a value-added recyclable organocatalyst for transamidation reaction.  相似文献   
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