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91.
92.
Blood fluidity is related to the ability to oxidize lipids at exercise   总被引:5,自引:0,他引:5  
We previously reported in rugbywomen correlations between RBC deformability and the ability to oxidize at exercise more lipids. This surprising finding might of course be spurious, or reflect the importance of the balance of substrates at exercise on baseline parameters that regulate blood rheology. Actually, the capacity of skeletal muscle to utilize either lipid or carbohydrate as fuels strongly influences whole body metabolism both at rest and during exercise. While the healthy skeletal muscle has substantial metabolic flexibility and is able to switch from predominantly lipid o oxidation during fasting or endurance exercise to increased glucose oxidation in conditions of insulin stimulation, obese individuals and those with type 2 diabetes manifest higher lipid oxidation during insulin-stimulated conditions despite lower rates of lipid oxidation during fasting or prolonged exercise. A low ability to oxidize and to periodically deplete triglyceride in muscle is associated with raised blood lipids. In addition, high carbohydrate oxidation rates in the mitochondrion are likely to promote more free radical generation. An increase in either blood lipids or free radicals is likely to induce profound hemorheological effects. We present here hemorheological studies in various populations with the use of exercise calorimetry in order to assess this switch of substrates. These studies further evidence negative correlations between the ability to oxidize lipids at exercise and parameters of blood viscosity. Correlations found between RBC deformability and the ability to oxidize at exercise more lipids may be due to effects of endurance training on lipid oxidation which may in turn modify both lipid metabolism and free radical generation, thus influencing RBC rheology.  相似文献   
93.
OBJECTIVE: The feasibility of gene transfer to myocardial tissue using viral vectors was investigated over the last few years. In this study we report gene transfer using a recently described improved of Herpes simplex virus (HSV-1)-derived amplicon vectors and demonstrate that these vectors are a powerful and potentially very interesting tool for gene transfer into neonatal primary as well as in adult cardiac myocytes. METHODS AND RESULTS: Non-pathogenic HSV-1 amplicon vectors simultaneously expressing GFP and LacZ were constructed using a novel helper system that yields essentially helper-free vector particles. These vectors were used to infect either cultured primary neonatal rat cardiomyocytes or adult cardiac tissue. Transgenic expression was quantified using a FACS (GFP) or X-gal staining (LacZ). Infection of primary cardiomyocytes showed efficient transduction even at very low multiplicity of infection (MOI), and expression increased with the infectious dose. By investigating release of lactate dehydrogenase (LDH) or spontaneous beating of the cells, we failed to detect cytotoxic effects in cardiomyocytes infected at high MOI. Thin slices of adult cardiac tissue placed in medium containing vectors also showed very good levels of transduction, without any evidence of toxic effects. CONCLUSIONS: Helper-free amplicon vectors very efficiently transduce genes into cardiomyocytes. Our results indicate similar or better transduction efficiencies than those reported using other vector systems. Furthermore, the very high transgenic capacity of amplicon vectors (up to 150 kbp) makes these vectors a unique and very suitable system to transduce large genomic sequences into cardiomyocytes.  相似文献   
94.

BACKGROUND

Diet quality is associated with brain aging outcomes. However, few studies have explored in humans the brain structures potentially affected by long-term diet quality. We examined whether cumulative average of the Alternative Healthy Eating Index 2010 (AHEI-2010) score during adult life (an 11-year exposure period) is associated with hippocampal volume.

METHODS

Analyses were based on data from 459 participants of the Whitehall II imaging sub-study (mean age [standard deviation] (SD)?=?59.6 [5.3] years in 2002-2004, 19.2% women). Multimodal magnetic resonance imaging examination was performed at the end of follow-up (2015-2016). Structural images were acquired using a high-resolution 3-dimensional T1-weighted sequence and processed with Functional Magnetic Resonance Imaging of the Brain Software Library (FSL) tools. An automated model-based segmentation and registration tool was applied to extract hippocampal volumes.

RESULTS

Higher AHEI-2010 cumulative average score (reflecting long-term healthy diet quality) was associated with a larger total hippocampal volume. For each 1 SD (SD?=?8.7 points) increment in AHEI-2010 score, an increase of 92.5 mm3 (standard error?=?42.0 mm3) in total hippocampal volume was observed. This association was independent of sociodemographic factors, smoking habits, physical activity, cardiometabolic health factors, cognitive impairment, and depressive symptoms, and was more pronounced in the left hippocampus than in the right hippocampus. Of the AHEI-2010 components, no or light alcohol consumption was independently associated with larger hippocampal volume.

CONCLUSIONS

Higher long-term AHEI-2010 scores were associated with larger hippocampal volume. Accounting for the importance of hippocampal structures in several neuropsychiatric diseases, our findings reaffirm the need to consider adherence to healthy dietary recommendation in multi-interventional programs to promote healthy brain aging.  相似文献   
95.
96.
HIV infection has become a chronic disease, with a lower mortality, but a consequent increase in age-related noninfectious comorbidities. Metabolic disorders have been linked to the effect of cART as well to the effects of immune activation and chronic inflammation. Whereas it is known that aging is intrinsically associated with hyperinflammation and immune system deterioration, the relative impact of chronic HIV infection on such inflammatory and immune activation has not yet been studied focusing on an elderly HIV-infected population.The objectives of the study were to assess 29 blood markers of immune activation and inflammation using an ultrasensitive technique, in HIV-infected patients aged ≥75 years with no or 1 comorbidity (among hypertension, renal disease, neoplasia, diabetes mellitus, cardiovascular disease, stroke, dyslipidemia, and osteoporosis), in comparison with age-adjusted HIV-uninfected individuals to identify whether biomarkers were associated with comorbidities. Wilcoxon nonparametric tests were used to compare the levels of each marker between control and HIV groups; logistic regression to identify biomarkers associated to comorbidity in the HIV group and principal component analysis (PCA) to determine clusters associated with a group or a specific comorbidity.A total of 111 HIV-infected subjects were included from the Dat’AIDS cohort and compared to 63 HIV-uninfected controls. In the HIV-infected group, 4 biomarkers were associated with the risk of developing a comorbidity: monocyte chemoattractant protein-1 (MCP-1), neurofilament light chain (NF-L), neopterin, and soluble CD14. Six biomarkers (interleukin [IL]-1B, IL-7, IL-18, neopterin, sCD14, and fatty acid-binding protein) were significantly higher in the HIV-infected group compared to the control group, 11 biomarkers (myeloperoxydase, interleukin-1 receptor antagonist, tumor necrosis factor receptor 1, interferon-gamma, MCP-1, tumor necrosis factor receptor 2, IL-22, ultra sensitivity C-reactive protein, fibrinogen, IL-6, and NF-L) were lower. Despite those differences, PCA to determine clusters associated with a group or a specific comorbidity did not reveal clustering nor between healthy control and HIV-infected patients neither between the presence of comorbidity within HIV-infected group.In this highly selected geriatric HIV population, HIV infection does not seem to have an additional impact on age-related inflammation and immune disorder. Close monitoring could have led to optimize prevention and treatment of comorbidities, and have limited both immune activation and inflammation in the aging HIV population.  相似文献   
97.
Clinical Rheumatology - To examine the mortality rates and causes of death among French decedents with Behçet’s disease (BD). Data collected between 1979 and 2016 by the French...  相似文献   
98.
Measles virus was isolated from the middle ear fluid (MEF) of two infant cases of acute otitis media (AOM) associated with measles. This is the first report on the isolation of measles virus from the MEF in patients with AOM, and possibility of the measles virus as a causative agent of AOM was suggested.  相似文献   
99.
PC is produced in the liver and inhibits blood coagulation by catalyzing active factors V and VIII. PC deficiency causes abnormal blood clotting that is difficult to regulate by anticoagulative treatments. Four reports of PC deficiency treated with LTx have been published; however, no report of DLT as a therapy for PC deficiency is available. We describe a case of a 23‐month‐old girl who received DLT for compound heterozygous PC deficiency. Her PC activity was below 5%. She developed intracranial lesion and frequent refractory purpura fulminans. Both her parents had heterozygous mutations of PC genes and were excluded as living donors. Furthermore, she was a low priority on the waiting list of deceased‐donor transplantation. We performed living DLT using the liver from a patient with MSUD. Activated PC concentrate safely supported the perioperative period. After DLT, she maintained normal PC activities and BCAA levels. This is the first case of PC deficiency successfully treated by living DLT with MSUD. We propose that DLT using liver from patients with MSUD is a treatment option for PC deficiency.  相似文献   
100.
Ovulation is caused by a sequence of neuroendocrine events: GnRH and LH surges that are induced by positive feedback action of estrogen secreted by the mature ovarian follicles. The central mechanism of positive feedback action of estrogen on GnRH/LH secretion, however, is not fully understood yet. The present study examined whether metastin, the product of metastasis suppressor gene KiSS-1, is a central neuropeptide regulating GnRH/LH surge and then estrous cyclicity in the female rat. Metastin had a profound stimulation on LH secretion by acting on the preoptic area (POA), where most GnRH neurons projecting to the median eminence are located, because injection of metastin into the third ventricle or POA increased plasma LH concentrations in estrogen-primed ovariectomized rats. Metastin neurons were immunohistochemically found in the arcuate nucleus (ARC) to be colocalized with estrogen receptors with some fibers in the preoptic area (POA) in close apposition with GnRH neuronal cell bodies or fibers. Quantitative RT-PCR has revealed that KiSS-1 and GPR54 mRNAs were expressed in the ARC and POA, respectively. The blockade of local metastin action in the POA with a specific monoclonal antibody to rat metastin completely abolished proestrous LH surge and inhibited estrous cyclicity. Metastin-immunoreactive cell bodies in the ARC showed a marked increase and c-Fos expression in the early proestrus afternoon compared with the day of diestrus. Thus, metastin released in the POA is involved in inducing the preovulatory LH surge and regulating estrous cyclicity.  相似文献   
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