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81.
Wnt/β-catenin signaling pathway plays a crucial role in diabetic cardiomyopathy (DCM), thus we aimed at investigating the effect of one therapeutic approach with resveratrol (RSV) given systemically and combined treatment of RSV with mesenchymal stem cells (MSCs) that was either RSV-preconditioned or not on Wnt/β-catenin signaling pathway in streptozotocin-induced DCM, and to evaluate effects of RSV preconditioning on MSCs therapeutic potential. The rats were divided into control (C, n = 8), diabetic (DM, n = 8), diabetic treated with systemic RSV (DM-RSV, n = 8), diabetic treated with RSV and nonconditioned MSCs (DM-RSV-MSCs, n = 8), diabetic treated with RSV and RSV-incubated with MSCs (DM-RSV-MSCc, n = 8) and diabetic treated with RSV-conditioned MSCs (DM-MSCc, n = 8). Echocardiography (Echo) showed significant improvement of cardiac functions in all groups treated with RSV either systemic or added in culture media. Data of ejection fraction (EF%) of DM-RSV-MSCc (81.50; interquartile range [IQR], 80.00–83.00) was comparable to both DM-RSV-MSCs (77.50; IQR, 71.50–79.00), and DM-MSCc (71.50; IQR, 70.00–74.50). Histological examination of the left ventricles was performed for all groups. DM group revealed significant myocardial hypertrophy, apoptosis, interstitial fibrosis, and microvascular affection. All treated groups were associated, in variable degrees, with attenuation of cardiac hypertrophy and fibrosis, decreased area% for cardiac immunostaining of secreted frizzled-related protein (sFRP2) and Wnt/β-catenin and improvement of the microvasculature. In conclusion, MSCs pretreated with resveratrol for 7 days showed increased 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and combined use of RSV (systemically and in culture media) significantly could improve cardiac remodeling capacity of MSCs via attenuation of sFRP2-mediated fibrosis and the downstream Wnt/β-catenin pathway.  相似文献   
82.
Macrophage migration inhibitory factor (MIF) is a ubiquitous cytokine that functions in reproduction and plays an important role in sperm maturation and motility. Here we reveal a correlation between MIF levels in human seminal fluid and fertility status. We identify an abnormal biphasic profile of MIF in the seminal fluid of patients with impaired sperm parameters. Our findings may be of interest for the development of a diagnostic method for fertility status.  相似文献   
83.
The key mimetic features of hoverflies through avian eyes   总被引:1,自引:0,他引:1  
Batesian mimicry occurs when a palatable species (the mimic) gains protection from predators by resembling an unpalatable or otherwise protected species (the model). While some mimetic species resemble their models closely, other species ('imperfect mimics') are thought to bear only a crude likeness. In an earlier study, pigeons (Columba livia) were trained to recognize wasp images in one experiment and non-mimetic (NM) fly images in another by rewarding the pigeons for pecking on the respective image types. These pigeons were subsequently presented with different images, including seemingly wasp-like hoverfly species, and the recorded peck rates on these images were used as a measure of the pigeons' perception of the hoverflies' mimetic similarity. To identify a candidate set of morphological features that the pigeons used when assessing this mimetic similarity, we first extracted a range of biometrical measurements from images originally presented to the pigeons. We then repeatedly optimized an empirical model in an attempt to match the recorded pigeon peck rates while using as few biometrical features as input as possible. Our models were able to fit the pigeon peck rates with considerable accuracy even while excluding many input features. Antennal length, a feature commonly used to discriminate between flies and wasps, was regularly retained as an input variable, but overall a different set of biometrical features was important for predicting the peck rates of pigeons rewarded for identifying wasps compared to those rewarded for identifying NM flies. In highlighting the importance of specific biometrical features in promoting mimicry and the irrelevance of others, our optimized models provide an explanation as to why certain species that appear to be poor mimics to humans are judged to be good mimics by birds.  相似文献   
84.
Traumatic brain injury features deficits are often ameliorated by dopamine (DA) agonists. We have previously shown deficits in striatal DA neurotransmission using fast scan cyclic voltammetry after controlled cortical impact (CCI) injury that are reversed after daily treatment with the DA uptake inhibitor methylphenidate (MPH). The goal of this study was to determine how a single dose of MPH (5 mg/kg) induces changes in basal DA and metabolite levels and with electrically evoked overflow (EO) DA in the striatum of CCI rats. MPH-induced changes in EO DA after a 2-week daily pre-treatment regime with MPH was also assessed. There were no baseline differences in basal DA or metabolite levels. MPH injection significantly increased basal [DA] output in dialysates for control but not injured rats. Also, MPH injection increased striatal peak EO [DA] to a lesser degree in CCI (176% of baseline) versus control rats (233% of baseline). However, daily pre-treatment with MPH resulted in CCI rats having a comparable increase in EO [DA] after MPH injection when compared with controls. The findings further support the concept that daily MPH therapy restores striatal DA neurotransmission after CCI.  相似文献   
85.

Background

Increased urbanization in the developing world parallels a rising burden of chronic diseases. Developing countries account for ∼80% of global cardiovascular (CV) deaths, but contribute a paucity of systematic epidemiological data on CV risk factors.

Objective

To estimate the prevalence of CV risk factors in rural and urban cohorts attending general practice clinics in the Africa and Middle East (AfME) region.

Methods

In a cross-sectional epidemiological study, the presence of CV risk factors (hypertension, diabetes mellitus (diabetes), dyslipidemia, obesity, smoking and abdominal obesity) were evaluated in stable adult outpatients attending general practice primary care clinics. A rural population was defined as isolated (>50 km or lack of easy access to commuter transportation) from urban centers.

Results

4,378 outpatients were systematically recruited from 94 clinics across 14 AfME countries. Mean age was 46±14 years and 52% of outpatients were female. A high prevalence of dyslipidemia (70%) and abdominal obesity (68%) were observed, followed by hypertension (43%) and diabetes (25%). The vast majority of outpatients (92%) had at least one modifiable CV risk factor, many (74%) had more than one, and half (53%) had 3 or more. These findings were observed in both genders and across urban and rural centers. Among outpatients with pre-existing hypertension or dyslipidemia, many were not at their target blood pressure or LDL-cholesterol goals.

Conclusion

Cardiovascular risk factors are highly prevalent among relatively young, stable outpatients attending general practice clinics across AfME. The findings support opportunistic screening for CV risk factors whenever outpatients visit a general practitioner and provide an opportunity for early identification and management of CV risk factors, including lifestyle interventions.  相似文献   
86.
Gastric pathology is a common complication in diabetes mellitus. The aim of the study was to evaluate the functions and morphological changes of the parietal cells of the rat stomach after streptozotocin-induced diabetes. Diabetes mellitus was induced in Wistar rats by a single intraperitoneal injection of streptozotocin (60 mg/kg body weight). The rats were weighed weekly and sacrificed after 6 months. The glandular portion of the stomach was removed and processed for H+-K+-ATPase immunohistochemistry and light and electron microscopy studies. Acid secretion was measured in vivo. After 6 months of diabetes, the mean weight of the rats was significantly lower (P < 0.001) compared to control. The mean weight of the stomach to body weight percentage increased significantly (P < 0.001) compared to control. The blood glucose level in diabetic rats was significantly higher (P < 0.001) than in normal control. Diabetic rats showed significant (P < 0.001) decrease in basal and stimulated acid secretion when compared to control. Electron micrographs of the parietal cells of glandular stomach of diabetic rats revealed significant (P < 0.0002) reduction in the number of mitochondria and a small though not significant increase in the number of canaliculi in the parietal cells compared with normal. Immunohistochemistry showed reduced H+-K+-ATPase (P < 0.00001) compared to control. Long-term diabetes induces morphological as well as functional changes in gastric parietal cells. The decrease in the number of mitochondria accompanied by reduced in H+-K+-ATPase in parietal cells may explain the reduced acid secretion observed in diabetics.  相似文献   
87.
88.
We describe an isotope dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of succinylacetone (SA) in urine for the diagnosis of hepatorenal tyrosinemia (HT1). The method used 15N-labeled 5(3)-methyl-3(5)-isoxazole propionic acid as internal standard. Urine samples were oximated with hydroxylamine hydrochloride at 80 degrees C, extracted by solvent-solvent extraction, and followed by derivatization of the butyl ester. The butylated isoxazole derivatives of SA and its internal standard were detected and quantified using positive ion electrospray LC-MS/MS with selected reaction monitoring. The turnaround time between injections was 10 min. Calibration curves were linear over the range of 0.0633-63.3 micromol/L. The intra- and interday assay variations were less than 7%. Mean recoveries of SA at three different concentrations ranged from 96 to 109%. During the course of this study, we identified 12 new patients with HT1 and applied this method to follow up the treatment of 4 of these patients as well as previously diagnosed HT1 patients.  相似文献   
89.
Succinylacetone (SA) is a specific marker for the inherited metabolic disease, hepatorenal tyrosinemia. We developed a stable-isotope dilution liquid chromatography tandem mass spectrometry for the determination of SA in dried blood spots (DBS) and liquid urine using a (13)C(4)-SA as internal standard. SA was extracted, converted to the butyl ester and derivatized with dansylhydrazine (Dns-H). Calibration curves in DBS and urine calibrators were linear up to 100 and 30 microM, respectively. At a signal-to-noise ratio of 3, the limits of detection in DBS and urine were 0.2 and 0.005 microM, respectively. Total run time was 5 min. Intra- and inter-assay precision expressed as coefficient of variation were better than 9.1% with more than 96% recovery. The method was applied retrospectively and prospectively for the diagnosis of hepatorenal tyrosinemia and for follow-up of patients under treatment.  相似文献   
90.
Ethanol extracts, dried powders and fibres (total and soluble fibre) of the tropical red algae Kappaphycus alvarezii, Kappaphycus striatus and Eucheuma denticulatum were analysed for their effect on lipase and α-amylase activity using turbidimetric method and dinitrosalicylic acid (DNS) assay, respectively. The nutrient composition analyses were determined using standard methods. The ethanol extract of dried K. striatus (Ks-III) showed the highest reduction in lipase activity with 92 % inhibition followed by seaweed powders (K. alvarezii (Ka-III), K. striatus (Ks-III) and E. denticulatum (Ed-III)) with average inhibition of 60 %. Soluble fibres of K. alvarezii (Ka-V) and E. denticulatum (Ed-V) showed significant inhibition with 60 and 57 % reduction, respectively. Only the ethanol extract of fresh E. denticulatum (Ed-I) showed 88 % inhibition of α-amylase. Nutritional component analyses showed that all three seaweeds are low in crude fat, suggesting the possible use of seaweed as a dietary supplement and for potential weight and glycaemia management.  相似文献   
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