646 research outputs found

    Multiple Venous Malformations as a Cause of Pulsatile Tinnitus.

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    INTRODUCTION: Pulsatile tinnitus is a relatively common presentation in otolaryngology clinics, most cases of which have a treatable cause. This presentation warrants a thorough workup to identify treatable, and rule out life-threatening, etiologies. We present a case of a patient with pulsatile tinnitus arising from multiple dilated venous channels in the head and neck. Case Presentation. We present the case of a 65-year-old Caucasian female with a two-year history of progressive, bilateral pulsatile tinnitus, which had become debilitating. Computed-tomographic angiography (CTA) studies ruled out an intracranial vascular cause for her symptoms. However, computed tomography (CT) scanning and magnetic resonance imaging (MRI) revealed multiple dilated bilateral, low-flow, venous channels throughout the head and neck. The proximity of such dilated venous channels to the temporal bone provides a route for sound to be transmitted to the inner ear. CONCLUSION: Arterial, venous, and systemic etiologies can cause pulsatile tinnitus. Arteriovenous malformations (AVMs) of the head and neck represent less than 1% of cases. In our patient, dilated low-flow venous malformations are the likely source of her symptoms, which is the first reported case in the literature.Peer Reviewe

    Bacterial Exopolysaccharides as New Natural Coagulants for Surface Water Treatment

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    Abstract: Coagulation-flocculation step is one of the most important steps during surface w ate r tre atm e n t. Che m ic al co ag ul an ts are o rdin ary use d such as al um . Howe ve r, the se chemical coagulants are dangerous to environment and human health. Natural coagulants derived from natural sources receive much attention during last years. This study aimed to isolate new bacterial exopolysaccharides from Bacillus licheniformis, B. insolitus and B. alvei to be used as natural coagulants during coagulation-flocculation process. Efficiency of extracted bacterial exopolysaccharides was examined through removal ability of bacterial indicators and some physicochemical parameters of River Nile water samples. Bacterial exopolysaccharides showed great removal percent when used as sole coagulant materials. Addition of alum to bacterial exopolysaccharides enhance removal efficiency

    Malaria Parasitemia during delivery

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    Objectives:  The aim of this study is to investigate the impact of plasmodium falciparum infection in parturient women in Central Sudan where malaria transmission is mesoendemic. The purpose of this paper is to find out the prevalenceof malaria parasitemia and the risk of anemia among parturient women and to suggest appropriate strategies to lower their prevalence rates. Methods:  This prospective study was conducted at Medani Teaching Hospital, Sudan a tertiary regional referral center, during the period January 1997 through to December 1997. All cases were admitted during labor to the delivery room and were clinically suspected to have malaria. History, examination and investigations were carried out on all patients. Results: The total number of patients enrolled in this study was 550, amounting to 14.9% of all women (N=3,687) who delivered during the study period. The prevalence of malaria parasitemia was 58.9% (N=550) while prevalence of anemia (defined as hemoglobulin   â€¦.9.0 g/dl) was 24.1% the mean hemoglobuin levels in patients with positive and negative malaria parasitemia was 9.72+ 1.62 and 9.85+ 1.60 g/dl. Statistically the difference in the mean hemoglobulin level was not significant, t=0.879, A significant negative correlation between parasite count in maternal blood and hemoglobulin level of the mother, was observed, where r=0.121 (P=0.032). out of 17 (3.3%) patients who had used chloroquine tablets for prophylaxis, 11patients still had positive parasitemia. Although there was a higher parasite count in those 11 patients, statistically the difference was not significance where P< 0.0

    Scaffold hopping of α-rubromycin enables direct access to FDA-approved cromoglicic acid as a SARS-CoV-2 M<sup>Pro</sup> inhibitor

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    The COVID-19 pandemic is still active around the globe despite the newly introduced vaccines. Hence, finding effective medications or repurposing available ones could offer great help during this serious situation. During our anti-COVID-19 investigation of microbial natural products (MNPs), we came across α-rubromycin, an antibiotic derived from Streptomyces collinus ATCC19743, which was able to suppress the catalytic activity (IC50 = 5.4 µM and Ki = 3.22 µM) of one of the viral key enzymes (i.e., MPro). However, it showed high cytotoxicity toward normal human fibroblasts (CC50 = 16.7 µM). To reduce the cytotoxicity of this microbial metabolite, we utilized a number of in silico tools (ensemble docking, molecular dynamics simulation, binding free energy calculation) to propose a novel scaffold having the main pharmacophoric features to inhibit MPro with better drug-like properties and reduced/minimal toxicity. Nevertheless, reaching this novel scaffold synthetically is a time-consuming process, particularly at this critical time. Instead, this scaffold was used as a template to explore similar molecules among the FDA-approved medications that share its main pharmacophoric features with the aid of pharmacophore-based virtual screening software. As a result, cromoglicic acid (aka cromolyn) was found to be the best hit, which, upon in vitro MPro testing, was 4.5 times more potent (IC50 = 1.1 µM and Ki = 0.68 µM) than α-rubromycin, with minimal cytotoxicity toward normal human fibroblasts (CC50 &gt; 100 µM). This report highlights the potential of MNPs in providing unprecedented scaffolds with a wide range of therapeutic efficacy. It also revealed the importance of cheminformatics tools in speeding up the drug discovery process, which is extremely important in such a critical situation

    Empirical shear based model for predicting plate end debonding in FRP strengthened RC beams

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    This paper presents the development of a simplified model for predicting plate end (PE) debonding capacity of reinforced concrete (RC) beams flexurally strengthened using fiber reinforced polymers (FRP). The proposed model is based on the concrete shear strength of the beams considering main parameters known to affect the opening of the shear cracks and consequently affect PE debonding. The model considers also the effect of the location of the cut-off point of FRP plate along the span of the beam. The proposed model was verified against experimental database of 128 FRP-strengthened beams collected from previous studies that failed in PE debonding. In addition, the predictions of the proposed model were also compared with those of the existing PE debonding models. The predictions of the model were found to be comparable to the best predictions provided by the existing models, yet the proposed model is simpler. Furthermore, the proposed model was combined with the ACI 440 IC debonding equation to provide a procedure for predicting the governing debonding failure mode in FRP strengthened RC beams. The procedure was validated against 238 beam tests available in the literature, and shown to be a reliable approach

    Inhibition of growth of Leishmania donovani promastigotes by newly synthesized 1,3,4-thiadiazole analogs

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    AbstractLeishmania donovani, the causative agent of visceral leishmaniasis, is transmitted by sand flies and replicates intracellularly in their mammalian host cells. The emergence of drug-resistant strains has hampered efforts to control the spread of the disease worldwide. Forty-four 1,3,4-thiadiazole derivatives and related compounds were tested in vitro for possible anti-leishmanial activity against the promastigotes of L. donovani. Micromolar concentrations of these agents were used to study the inhibition of multiplication of L. donovani promastigotes. Seven compounds were identified with potential antigrowth agents of the parasite. Compound 4a was the most active at 50μM followed by compound 3a. These compounds could prove useful as a future alternative for the control of visceral leishmaniasis

    Thymoquinone attenuates diethylnitrosamine induction of hepatic carcinogenesis through antioxidant signaling

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    Hepatocellular carcinoma accounts for about 80–90% of all liver cancer and is the fourth most common cause of cancer mortality. Although there are many strategies for the treatment of liver cancer, chemoprevention seems to be the best strategy for lowering the incidence of this disease. Therefore, this study has been initiated to investigate whether thymoquinone (TQ), Nigella sativa derived-compound with strong antioxidant properties, supplementation could prevent initiation of hepatocarcinogenesis-induced by diethylnitrosamine (DENA), a potent initiator and hepatocarcinogen, in rats. Male Wistar albino rats were divided into four groups. Rats of Group 1 received a single intraperitoneal (I.P.) injection of normal saline. Animals in Group 2 were given TQ (4 mg/kg/day) in drinking water for 7 consecutive days. Rats of Group 3 were injected with a single dose of DENA (200 mg/kg, I.P.). Animals in Group 4 were received TQ and DENA. DENA significantly increased alanine transaminase (ALT), alkaline phosphatase (ALP), total bilirubin, thiobarbituric acid reactive substances (TBARS) and total nitrate/nitrite (NOx) and decreased reduced glutathione (GSH), glutathione peroxidase (GSHPx), glutathione-s-transferase (GST) and catalase (CAT) activity in liver tissues. Moreover, DENA decreased gene expression of GSHPx, GST and CAT and caused severe histopathological lesions in liver tissue. Interestingly, TQ supplementation completely reversed the biochemical and histopathological changes induced by DENA to the control values. In conclusion, data from this study suggest that: (1) decreased mRNA expression of GSHPx, CAT and GST during DENA-induced initiation of hepatic carcinogenesis, (2) TQ supplementation prevents the development of DENA-induced initiation of liver cancer by decreasing oxidative stress and preserving both the activity and mRNA expression of antioxidant enzymes

    Proanthocyanidin Attenuation of Oxidative Stress and NF- κ

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    Hyperlipidemia and hyperglycemia result in oxidative stress and play a major role in the development of diabetic nephropathy (DN). We explored the effects of proanthocyanidin (PA) on the induction and progression of DN in apolipoprotein E-deficient mice. Diabetes Mellitus was induced in ten-week-old male apoE−/−mice using streptozotocin (STZ). Mice were fed with a high-fat diet in presence or absence of PA. PA treatment significantly reduced the high cholesterol levels, restored renal functions, and reduced albuminuria in the PA-treated diabetic mice compared with the diabetic untreated mice. In addition, the glomerular mesangial expansion in the diabetic mice was attenuated as a result of PA supplementation. Moreover, PA treatment restored the elevated levels of MDA and CML and the reduced activity of SOD and GSH in the diabetic mice. Furthermore, PA feeding reduced the activation and translocation of NF-κB to the nucleus compared with the diabetic untreated animals. Reduction of NF-κB activation resulted in the attenuation of the expression of IL-6, TGFβ, and RAGE which protected PA-treated mice against DN. The renoprotective effects of PA were found to be time independent regardless of whether the dietary feeding with PA was started pre-, co-, or post-STZ injection. In conclusion, part of the beneficial effects of PA includes the disruption of the detrimental AGE-RAGE-NFκB pathways

    Rumex dentatus L. phenolics ameliorate hyperglycemia by modulating hepatic key enzymes of carbohydrate metabolism, oxidative stress and PPARγ in diabetic rats

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    Rumex dentatus L. is a flowering plant with promising therapeutic effects. This study investigated the antioxidant efficacy of phenolic compounds isolated from R. dentatus L. in vitro and by conducting density function theory (DFT) studies to explore the mechanisms of action. The antioxidant, anti-inflammatory and antidiabetic effects of polyphenols-rich R. dentatus extract (RDE) were investigated in type 2 diabetic rats. Phytochemical investigation of the aerial parts of R. dentatus resulted in the isolation of one new and seven known compounds isolated for the first time from this species. All isolated phenolics showed in vitro radical scavenging activity. The antioxidant activity of the compounds could be oriented by the hydrogen atom transfer and sequential proton loss electron transfer mechanisms in gas and water phases, respectively. In diabetic rats, RDE attenuated hyperglycemia, insulin resistance and liver injury and improved carbohydrate metabolism. RDE suppressed oxidative stress and inflammation and upregulated PPARγ. In silico molecular docking analysis revealed the binding affinity of the isolated compounds toward PPARγ. In conclusion, the computational calculations were correlated with the in vitro antioxidant activity of R. dentatus derived phenolics. R. dentatus attenuated hyperglycemia, liver injury, inflammation and oxidative stress, improved carbohydrate metabolism and upregulated PPARγ in diabetic ratsThis work has DGI Project no. CTQ2015-63997-C2, a generous allocation of computing time at the Centro de Computación Científica of the UAM is also acknowledge
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