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1.
Restriction fragment length polymorphisms (RFLPs) at the apolipoprotein AI-CIII-AIV gene cluster and their association with coronary artery disease (CAD) and lipid levels were studied in a Northern Greek population. Ninety-five patients with CAD and fifty-four normal controls, angio-graphically proven, were included in this study. Using genomic hybridization techniques, three polymorphic restriction sites were identified at this locus: the PstI at the 3' end of the apoAI gene, the SacI at the 3' non-coding region of the apoCIII gene and the PvuII at the intergenic region between the apoCIII-AIV genes. The rare allele (P2) arising from the absence of the PstI restriction site was observed with a significantly higher frequency (p<0.01) in patients compared to normals (0.11 vs 0.02). In contrast, the rare allele for the SacI polymorphic site had a similar distribution among patients and controls (0.12 vs 0.16). The same was observed for the PvuII RFLP (0.04 vs 0.05). Correlation of lipid and apolipoprotein AI levels with the three RFLPs revealed no significant association, although apo AI and HDL were lower in patients with the P2 allele. Thus, in this Greek population, only the PstI polymorphism, among the polymorphic restriction sites examined, appears to be associated with CAD.  相似文献   
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Skeletal differences exist between closely matched Black and White women, although it is unknown if similar differences also exist between Black and White men after controlling for age, body weight, and stature. The aim of this study was twofold: to test the hypothesis that Black men have greater bone mass, higher bone mineral density, and longer limbs compared to White men of similar age, weight, and height; and second, to establish if ethnic variation in skeletal characteristics has an impact on the models upon which three widely used methods for estimating total body fat are based. Twenty-four healthy Black men were matched by age (±5 years), height (±3 cm), and weight (±2 kg) to 24 healthy White men. Skeletal characteristics and body composition were studied using anatomical and compartment estimates derived by anthropometry, 3H2O dilution, hydrodensitometry, whole-body 40K counting, and dual photon systems. Black men had greater bone mineral mass (P = 0.007), higher bone density (P = 0.054), longer femurs (P = 0.002), longer anthropometric arm and thigh lengths (P = 0.001 and P = 0.002, respectively), lower spine to femur ratio (P = 0.004), and similar spine length (P = 0.271) compared to White men. Total body fat and fat-free body mass (FFM) were estimated in the men using a four-compartment model. Black and White men had similar total body fat, K (TBK), water (TBW), and FFM. Density of FFM and TBK/FFM were also similar between Black and White men, suggesting that current two-compartment hydrodensitometry and TBK models for estimating fat may not require adjustments for ethnicity. The TBW/FFM ratio, which is the main assumed steady-state relation for the two-compartment TBW method of estimating fat, was modestly increased (P = 0.05) in Black men (x? ± SD, 0.744 ± 0.018) compared to White men (0.732 ± 0.021). These results confirm that Black and White men differ significantly in some skeletal characteristics and these differences have implications in the study of both osteoporosis and human body composition. © 1994 Wiley-Liss, Inc.  相似文献   
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Coronavirus disease 2019 (COVID-19) due to SARS-CoV-2 is associated with a wide spectrum of disease, ranging from asymptomatic infection to acute respiratory distress syndrome. Some biomarkers may predict disease severity. Among them, the anti-SARS-CoV-2 antibody response has been related to severe disease. The aim of this study was to assess the correlation between the anti-SARS-CoV-2 serological response and COVID-19 outcome. Demographic, clinical, and biological data from nasopharyngeal-PCR confirmed COVID-19 hospitalized patients were prospectively collected between April and August 2020 at our institution. All patients had serial weekly serology testing for a maximum of three blood samples or until discharge. Two different serological assays were used: a chemiluminescent assay and an in-house developed Luminex immunoassay. Kinetics of the serological response and correlation between the antibody titers and outcome were assessed. Among the 70 patients enrolled in the study, 22 required invasive ventilation, 29 required non-invasive ventilation or oxygen supplementation, and 19 did not require any oxygen supplementation. Median duration of symptoms upon admission for the three groups were 13, 8, and 9 days, respectively. Antibody titers gradually increased for up to 3 weeks since the onset of symptoms for patients requiring oxygen supplementation with significantly higher antibody titers for patients requiring invasive ventilation. Antibody titers on admission were also significantly higher in severely ill patients and serology performed well in predicting the necessity of invasive ventilation (AUC: 0.79, 95% CI: 0.67–0.9). Serology testing at admission may be a good indicator to identify severe COVID-19 patients who will require invasive mechanical ventilation.  相似文献   
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Here we describe the design and synthesis of pyrazolo[3,4-d]pyridazines as adenosine receptor (AR) ligands. We demonstrate that the introduction of a 3-phenyl group, together with a 7-benzylamino and 1-methyl group at the pyrazolopyridazine scaffold, generated the antagonist compound 10b, which displayed 21 nM affinity and a residence time of ∼60 min, for the human A1R, 55 nM affinity and a residence time of ∼73 min, for the human A3R and 1.7 μΜ affinity for the human A2BR while not being toxic. Strikingly, the 2-methyl analog of 10b, 15b, had no significant affinity. Docking calculations and molecular dynamics simulations of the ligands inside the orthosteric binding area suggested that the 2-methyl group in 15b hinders the formation of hydrogen bonding interactions with N6.55 which are considered critical for the stabilization inside the orthosteric binding cavity. We, therefore, demonstrate that 10a is a novel scaffold for the development of high affinity AR ligands. From the mutagenesis experiments the biggest effect was observed for the Y2717.46A mutation which caused an ∼10-fold reduction in the binding affinity of 10b.  相似文献   
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Primary liver cancer or hepatocellular carcinoma (HCC) is one of the most frequent tumors representing the fifth commonest malignancy worldwide and the third cause of mortality from cancer. Currently, the treatments for HCC are not so effective and new strategies are needed for its fight. Chemoprevention, the use of natural or synthetic chemical agents to reverse, suppress or prevent carcinogenesis is considered an important way for confronting HCC. Many of the chemopreventive agents are phytochemicals, namely non-nutritive plant chemicals with protective or disease preventive properties. In this review, we focus on plant polyphenols, one of the most important classes of phytochemicals, their chemopreventive properties against HCC and discuss the molecular mechanisms accounting for this activity.  相似文献   
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Some patients with hypertrophic cardiomyopathy experience postprandial exacerbation of symptoms. The aim of this study was to determine whether the hemodynamic and/or hormonal responses to a meal differ between patients with and without postprandial symptoms. Ten hypertrophic cardiomyopathy patients with postprandial symptoms, 10 patients without postprandial symptoms, and 10 normal subjects ate a 740 Kcal meal, following which heart rate, blood pressure, and echocardiographic and gastrointestinal hormone changes were compared among the three groups. Heart rate increased (p<0.001) and diastolic blood pressure fell (p < 0.001) to a similar degree in the three groups. Left ventricular outflow tract velocity increased (p< 0.01) and some patients had substantial increases in outflow tract pressure gradient; however, this was independent of the presence or absence of postprandial symptoms. The atrial contribution to filling increased in normal subjects and in both groups of hypertrophic cardiomyopathy patients. There was no significant difference in the gastrointestinal hormone changes in the three groups. In summary, there is no evidence for a distinctive hemodynamic or hormonal response to food in hypertrophic cardiomyopathy patients with postprandial symptoms. These symptoms more likely reflect differences in underlying cardiac disease characteristics and severity.  相似文献   
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