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61.
Perinatal asphyxia in infants of insulin-dependent diabetic mothers   总被引:1,自引:0,他引:1  
Infants of diabetic mothers are thought to be at risk for perinatal asphyxia. We hypothesized that the following are significant risk factors for perinatal asphyxia: poor third-trimester glycemic control, diabetic vascular disease (nephropathy, retinopathy) appearing in pregnancy, pregnancy-associated hypertension, smoking, prematurity, fetal macrosomia, and maternal hyperglycemia and hypoglycemia within 6 hours preceding delivery. We prospectively studied 162 infants born to 149 diabetic mothers (White classes B through R-T). Perinatal asphyxia was defined clinically as fetal distress during labor (late decelerations, persistent fetal bradycardia, or both), 1-minute Apgar score less than or equal to 6, or intrauterine fetal death. Forty-four infants (26.7%) had perinatal asphyxia. The presence of perinatal asphyxia did not correlate with third-trimester glycemic control, pregnancy-associated hypertension, smoking, fetal macrosomia, or maternal hypoglycemia before delivery, but it did correlate significantly with nephropathy appearing in pregnancy, maternal hyperglycemia before delivery, and prematurity. We speculate that (1) the appearance of diabetic vasculopathy (nephropathy) during pregnancy is accompanied by placental vascular disease and subsequently by fetal compromise and (2) in pregnancy complicated by diabetes, maternal and subsequently fetal hyperglycemia before delivery leads to fetal hypoxemia.  相似文献   
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AIM: To assess the frequency and associated risk factors of diabetic retinopathy among Sudanese individuals with diabetes attending Makka Eye complex in Khartoum, Sudan. METHODS: The cross sectional hospital based study recruited 316 individuals with diabetes from Makkah Eye Complex Retina Clinic. Standard questionnaire was used to collect demographic data, medical history and life style characteristics. Blood samples were taken to measure HbA1c and lipid profile. Fundus and slit lamp examination were performed for screening of diabetic retinopathy. RESULTS: Among 316 participants, 187 (59.2%) were males and 129 (40.8%) were females. The mean age of participants was 58.7±10.5y. The overall frequency of retinopathy was 261 (82.6%). The percentages of the total participants with proliferative diabetic retinopathy (PDR) were 126 (39.9%) and non-proliferative diabetic retinopathy (NPDR) were 135 (42.7%). Importantly, duration of diabetes mellitus (DM) (72.2% of more than 10y), being on oral hypoglycaemic drugs (versus insulin), and hypertension were all significant risk factors for diabetic retinopathy (P=0.00, 0.01 and 0.00 respectively). Complications of diabetes like diabetic foot (17.7%), history of amputation (6.7%) and clinically significant macular edema (CSME) (47.4%) of the eyes were all significant risk factors (P<0.05). Logistic regression analysis showed that duration of diabetes, hypertension and CSME were found to be absolute risk factors (P=0.007, 0.003 and 0.000 respectively). Duration of DM of more than 10y have more than double risk (OR=2.8), while having hypertension triples the risk of retinopathy (OR=3.1). CONCLUSION: High rates of diabetic retinopathy are noted among individuals with diabetes attending Makkah Eye hospital in capital Khartoum. Urgent strategies are needed to monitor and treat hypertension and optimize diabetes control in individuals with diabetes. More investment in diabetes services is urgently needed.  相似文献   
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We present a novel method that can assay cellular viability in real-time using supervised machine learning and intracellular dynamic activity data that is acquired in a label-free, non-invasive, and non-destructive manner. Cell viability can be an indicator for cytology, treatment, and diagnosis of diseases. We applied four supervised machine learning models on the observed data and compared the results with a trypan blue assay. The cell death assay performance by the four supervised models had a balanced accuracy of 93.92 ± 0.86%. Unlike staining techniques, where criteria for determining viability of cells is unclear, cell viability assessment using machine learning could be clearly quantified.  相似文献   
66.
A capability for effective tissue reparation is a living requirement for all multicellular organisms. Bone exits as a precisely orchestrated balance of bioactivities of bone forming osteoblasts and bone resorbing osteoclasts. The main feature of osteoblasts is their capability to produce massive extracellular matrix enriched with calcium phosphate minerals. Hydroxyapatite and its composites represent the most common form of bone mineral providing mechanical strength and significant osteoinductive properties. Herein, hydroxyapatite and fluorapatite functionalized composite scaffolds based on electrospun polycaprolactone have been successfully fabricated. Physicochemical properties, biocompatibility and osteoinductivity of generated matrices have been validated. Both the hydroxyapatite and fluorapatite containing polycaprolactone composite scaffolds demonstrated good biocompatibility towards mesenchymal stem cells. Moreover, the presence of both hydroxyapatite and fluorapatite nanoparticles increased scaffolds’ wettability. Furthermore, incorporation of fluorapatite nanoparticles enhanced the ability of the composite scaffolds to interact and support the mesenchymal stem cells attachment to their surfaces as compared to hydroxyapatite enriched composite scaffolds. The study of osteoinductive properties showed the capacity of fluorapatite and hydroxyapatite containing composite scaffolds to potentiate the stimulation of early stages of mesenchymal stem cells’ osteoblast differentiation. Therefore, polycaprolactone based composite scaffolds functionalized with fluorapatite nanoparticles generates a promising platform for future bone tissue engineering applications.  相似文献   
67.
In this article, construction of amperometric sensor(s) based on screen-printed carbon electrodes covered by thin layers of two types of carbon nanomaterials serving as amplifiers, and containing [Cu(bipy)2Cl]Cl∙5H2O complex is reported. Their performance and biomimetic activity towards two selected neurotransmitters (dopamine and serotonin) was studied mainly using flow injection analysis (FIA). The important parameters of FIA such as working potential, flow rate, and pH were optimized. The mechanism of the catalytic activity is explained and experimentally confirmed. It reveals that presence of hydrogen peroxide plays a crucial role which leads to answer the title question: can presented complex really be considered as a tyrosinase biomimetic catalyst or only as a redox mediator?  相似文献   
68.
The extant literature has suggested relationships between an individual's chronotype (in relation to morningness/eveningness) and several outcomes, including addictive disorders, psychological distress and daytime sleepiness. Moreover, sleep quality has been proposed to be a mediator in the aforementioned relationships. Consequently, the aim of the present study was to investigate the complex relationship between morningness/eveningness, problematic social media use, psychological distress and daytime sleepiness, with the potential mediators of sleep quality and insomnia. All participants (N = 1,791 [30.1% males]; mean age = 27.2 years, SD = 10.1) completed a battery of psychometric scales, including a reduced version of the Morningness‐Eveningness Questionnaire (at baseline), the Pittsburgh Sleep Quality Index and Insomnia Severity Index (1 month after baseline assessment), the Bergen Social Media Addiction Scale, the Hospital Anxiety and Depression Scale, and the Epworth Sleepiness Scale (2 months after baseline assessment). The impacts of morningness‐eveningness on problematic social media use, anxiety, depression and daytime sleepiness were found in the mediation models. Furthermore, the mediated effects of insomnia and sleep quality were observed. The present study's results emphasize the importance of promoting healthy sleep habits and sleep hygiene behaviours, and that of early detection of sleep problems among individuals who have the eveningness chronotype, because this would significantly improve their health outcomes.  相似文献   
69.
AimDiabetic nephropathy (DN) is one of the worst complications of diabetes. Despite a growing number of DN metabolite profiling studies, most studies are suffering from inconsistency in their findings. The main goal of this meta-analysis was to reach to a consensus panel of significantly dysregulated metabolites as potential biomarkers in DN.Data synthesisTo identify the significant dysregulated metabolites, meta-analysis was performed by “vote-counting rank” and “robust rank aggregation” strategies. Bioinformatics analyses were performed to identify the most affected genes and pathways. Among 44 selected studies consisting of 98 metabolite profiles, 17 metabolites (9 up-regulated and 8 down-regulated metabolites), were identified as significant ones by both the meta-analysis strategies (p-value<0.05 and OR>2 or <0.5) and selected as DN metabolite meta-signature. Furthermore, enrichment analyses confirmed the involvement of various effective biological pathways in DN pathogenesis, such as urea cycle, TCA cycle, glycolysis, and amino acid metabolisms. Finally, by performing a meta-analysis over existing time-course studies in DN, the results indicated that lactic acid, hippuric acid, allantoin (in urine), and glutamine (in blood), are the topmost non-invasive early diagnostic biomarkers.ConclusionThe identified metabolites are potentially involved in diabetic nephropathy pathogenesis and could be considered as biomarkers or drug targets in the disease.Prospero registration numberCRD42020197697.  相似文献   
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