258 research outputs found

    Clinical manifestation and maternal complications and neonatal outcomes in pregnant women with COVID-19: a comprehensive evidence synthesis and meta-analysis

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    Objectives: There is little known about pregnancy-related complications and comorbidity in this group of women. Therefore, this systematic review and meta-analysis were performed to find out whether COVID-19 may cause different manifestations and outcomes in the antepartum and postpartum period or not. Material and methods: We searched databases, including Medline (PubMed), Embase, Scopus, Web of sciences, Cochrane library, Ovid, and CINHAL to retrieve all articles reporting the prevalence of maternal and neonatal complications, in addition to clinical manifestations, in pregnant women with COVID-19 that published with English language January to November 2020. Results: Seventy-four studies with total 5560 pregnant women included in this systematic review. The results show that the pooled prevalence of neonatal mortality, lower birth weight, stillbirth, premature birth, and intrauterine fetal distress in women with COVID-19 was 4 (95 Cl: 1 � 9), 21 (95 Cl: 11 � 31), 2 (95 Cl: 1 � 6), 28 (95 Cl: 13 � 43), and 14 (95 Cl: 4 � 25); respectively. Moreover, the pooled prevalence of fever, cough, diarrhea, and dyspnea were 56 (95 Cl: 32 � 81), 29 (95 Cl: 21 � 38), 9 (95 Cl: 2 � 16), and 3 (95 Cl: 1 � 6) in pregnant women with COVID-19. Two studies reported that pregnant women with severe COVID pneumonia have higher levels of d-dimer. Also, COVID pneumonia is more common in pregnant women than non-pregnant. Conclusion: According to this meta-analysis, pregnant women with COVID-19 with or without pneumonia, are at a higher risk of preeclampsia, preterm birth, miscarriage and cesarean delivery. Furthermore, the risk of LBW and intrauterine fetal distress seems to be increased in neonates. In addition, our evaluations are investigative of higher risk of COVID-19 in the third trimester in pregnant women comparing to the first and second trimester. It can be due to higher BMI in the third trimester causing to increase the likelihood of disease deterioration, which can trigger a cascade of side effects starting with coagulation, pneumonia, hypoxemia affecting the placenta leading to ICU admission, fetal distress, premature birth and higher rates of C-section. © 2021 Informa UK Limited, trading as Taylor & Francis Group

    Lavandula angustifolia biological characteristics: An in vitro study

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    Objective: Lavender is an aromatic shrub belonging to the Lamiaceae family. The flowers and leaves in different forms of extracts are used as herbal medicine. The accumulation of amyloid beta (Aβ) plaques, reduction of acetylcholine due to hyperactivity of acetylcholinesterase, and glutamate neurotoxicity are known to be involved in decreased level of cognitive function. In our previous study, we proved that the aqueous extract of lavender improves learning and memory. This in vitro study was designed to evaluate antiaggregative, antioxidant, and antiacetylcholinesterase activities of the herbal medicine. Methods: Thin layer chromatography, high-performance liquid chromatography, thioflavin, atomic force microscope (AFM), Elleman,and 2,2-diphenyl-1-picryl hydrazyl techniques were used for qualitative analysis, quantitative analysis, antiaggregative characteristics, anti-acetylcholinestrase activity and antioxidant activity of the lavender extract, respectively. Results: We found chromatographic peaks of caffeic acid and luteolin-7-glycosid in the lavender extract. Our results indicated that aqueous extract of lavender dose-dependently inhibits the formation of Aβ aggregate. The AFM technique showed that lavender largely diminished the Aβ fibril formation. We also observed a considerable radical scavenging activity of the extract. Conclusions: Prevention of Aβ plaque formation and antioxidant activity along with nontoxic features of the lavender extract promise possible effectiveness of this plant on improving some neurological disorders including Alzheimer's disease. © 2019 Wiley Periodicals, Inc

    Numerics of stochastic parabolic differential equations with stable finite difference schemes

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    Abstract In the present article, we focus on the numerical approximation of stochastic partial differential equations of Itˆo type with space-time white noise process, in particular, parabolic equations. For each case of additive and multiplicative noise, the numerical solution of stochastic diffusion equations is approximated using two stochastic finite difference schemes and the stability and consistency conditions of the considered methods are analyzed. Numerical results are given to demonstrate the computational efficiency of the stochastic methods

    A moving mesh method with variable relaxation time

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    We propose a moving mesh adaptive approach for solving time-dependent partial differential equations. The motion of spatial grid points is governed by a moving mesh PDE (MMPDE) in which a mesh relaxation time \tau is employed as a regularization parameter. Previously reported results on MMPDEs have invariably employed a constant value of the parameter \tau. We extend this standard approach by incorporating a variable relaxation time that is calculated adaptively alongside the solution in order to regularize the mesh appropriately throughout a computation. We focus on singular problems involving self-similar blow-up to demonstrate the advantages of using a variable relaxation ime over a fixed one in terms of accuracy, stability and efficiency.Comment: 21 page

    Adapted MMSE and TYM cognitive tests: how much powerful in screening for Alzheimer�s disease in Iranian people

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    Alzheimer�s disease (AD) is a major global health priority and providing an efficient way for early diagnosis of people developing dementia is important. The Mini-Mental State Examination (MMSE, total score = 30) and Test Your Memory (TYM, total score = 50) are widely used as screening tests for cognitive function. In the present study 174 subjects including healthy people (CON group) and those having Alzheimer�s disease (AD group) were introduced to MMSE and TYM cognitive tests adjusted to Iranian population. Sensitivities and specificities with optimal cut-off scores, area under curve (AUC), positive predictive value (PPV) and negative predictive value (NPV) were measured for both tests. The MMSE scores of the CON and AD groups were 23.77 ± 0.327 and 10.88 ± 0.762, respectively. The TYM scores were 44.32 ± 0.389 and 14.37 ± 1.368 in the CON and AD participants, respectively. Findings in the MMSE test were: AUC = 0.962, optimal cut-off score = 18.5, sensitivity = 0.90 and specificity = 0.96. Values in the TYM test were: AUC = 0.991, optimal cut-off score = 31, sensitivity = 0.90 and specificity = 1. We found no correlation between the cognitive performance and age in the CON group but a positive correlation in the AD patients. On the other hand, t-test analysis indicated that achievement of the test scores are significantly sex dependent, with more scores attained by the females. Taken together, in regard to correct classification rate (CCR); the TYM test seems to be more appropriate for cognitive screening in our study. However, considering an analogous AUC, both tests are comparable and have high sensitivity and specificity for discriminating between people with and without AD. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group

    Does severity of Alzheimer's disease contribute to its responsiveness to modifying gut microbiota? A double blind clinical trial

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    Alzheimer's disease (AD) is associated with cognitive dysfunction. Evidence indicates that gut microbiota is altered in the AD and, hence, modifying the gut flora may affect the disease. In the previous clinical research we evaluated the effect of a probiotic combination on the cognitive abilities of AD patients. Since, in addition to pathological disorders, the AD is associated with changes in oxidant/antioxidant and inflammatory/anti-inflammatory biomarkers, the present work was designed to evaluate responsiveness of the inflammatory and oxidative biomarkers to the probiotic treatment. The control (CON) and probiotic (PRO) AD patients were treated for 12 weeks by the placebo and probiotic supplementation, respectively. The patients were cognitively assessed by Test Your Memory (TYM = 50 scores). Also serum concentrations of nitric oxide (NO), glutathione (GSH), total antioxidant capacity (TAC), malondialdehyde (MDA), 8-hydroxy-2' -deoxyguanosine (8-OHdG) and cytokines (TNF-α, IL-6, and IL-10) were measured. The cognitive test and the serum biomarkers were assessed pre- and post-treatment. According to TYM test 83.5 of the patients showed severe AD. The CON (12.86 ± 8.33) and PRO (-9.35 ± 16.83) groups not differently scored the cognitive test. Not pronounced change percent was found in the serum level of TNF-α (1.67 ± 1.33 vs. -0.15 ± 0.27), IL-6 (0.35 ± 0.17 vs. 2.18 ± 0.15), IL-10 (0.05 ± 0.10 vs. -0.70 ± 0.73), TAC (0.07 ± 0.07 and -0.06 ± 0.03), GSH (0.08 ± 0.05 and 0.04 ± 0.03) NO (0.11 ± 0.06 and 0.05 ± 0.09), MDA (-0.11 ± 0.03 and -0.17 ± 0.03), 8-OHdG (43.25 ± 3.01 and 42.70 ± 3.27) in the CON and PRO groups, respectively. We concluded that the cognitive and biochemical indications in the patients with severe AD are insensitive to the probiotic supplementation. Therefore, in addition to formulation and dosage of probiotic bacteria, severity of disease and time of administration deeply affects results of treatment. © 2018 Agahi, Hamidi, Daneshvar, Hamdieh, Soheili, Alinaghipour, Esmaeili Taba and Salami

    The association between common C677T mutation in methylenetetrahydrofolate reductase gene and the risk of venous thrombosis in an Iranian population

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    Background: Venous thrombosis is a multicausal disease involving acquired and genetic factors. The prevalence of methylenetetrahydrofolate reductase (MTHFR) C677T genotypes and its association with venous thrombosis is not established in the Iranian population. In this study we investigated a possible association between fasting hyperhomocysteinemia and C677T mutation in the MTHFR gene with venous thrombosis. Materials and Methods: We studied 200 venous thrombotic patients and 100 healthy controls, of similar age and sex. Mutation analysis was carried out by PCR-RFLP, and the homocysteine level was measured by EIA. Results: No significant differences in the frequency of C677T genotypes were observed between patients and controls (P=0.2). The frequency of the T allele was 21 and 27.2 in controls and patients, respectively (odds ratio, 1.27; 95 CI, 0.83-1.94, P=0.15). Fasting homocysteine level was significantly higher in patients than controls (P=0.001). Conclusions: We concluded that hyperhomocysteinemia, but not MTHFR C677T mutation, is a significant risk factor for venous thrombosis in the Iranian population, and measuring the level of homocysteine is less expensive and more useful than the genetic test for the MTHFR mutation

    Rescaled coordinate descent methods for linear programming

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    We propose two simple polynomial-time algorithms to find a positive solution to Ax=0Ax=0 . Both algorithms iterate between coordinate descent steps similar to von Neumann’s algorithm, and rescaling steps. In both cases, either the updating step leads to a substantial decrease in the norm, or we can infer that the condition measure is small and rescale in order to improve the geometry. We also show how the algorithms can be extended to find a solution of maximum support for the system Ax=0Ax=0 , x≥0x≥0 . This is an extended abstract. The missing proofs will be provided in the full version

    Structural and Functional Reorganization of the Brain in Migraine Without Aura

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    It remains unknown whether migraine headache has a progressive component in its pathophysiology. Quantitative MRI may provide valuable insight into abnormal changes in the migraine interictum and assist in identifying disrupted brain networks. We carried out a data-driven study of structural integrity and functional connectivity of the resting brain in migraine without aura. MRI scanning was performed in 36 patients suffering from episodic migraine without aura and 33 age-matched healthy subjects. Voxel-wise analysis of regional brain volume was performed by registration of the T1-weighted MRI scans into a common study brain template using the tensor-based morphometry (TBM) method. Changes in functional synchronicity of the brain networks were assessed using probabilistic independent component analysis (ICA). TBM revealed that migraine is associated with reduced volume of the medial prefrontal cortex (mPFC). Among 375 functional brain networks, resting-state connectivity was decreased between two components spanning the visual cortex, posterior insula, and parietal somatosensory cortex. Our study reveals structural and functional alterations of the brain in the migraine interictum that may stem from underlying disease risk factors and the “silent” aura phenomenon. Longitudinal studies will be needed to investigate whether interictal brain changes are progressive and associated with clinical disease trajectories
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