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91.
Coronavirus disease 2019 (COVID-19) remains a major public health concern, and vaccine unavailability, hesitancy, or failure underscore the need for discovery of efficacious antiviral drug therapies. Numerous approved drugs target protein kinases associated with viral life cycle and symptoms of infection. Repurposing of kinase inhibitors is appealing as they have been vetted for safety and are more accessible for COVID-19 treatment. However, an understanding of drug mechanism is needed to improve our understanding of the factors involved in pathogenesis. We tested the in vitro activity of three kinase inhibitors against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including inhibitors of AXL kinase, a host cell factor that contributes to successful SARS-CoV-2 infection. Using multiple cell-based assays and approaches, gilteritinib, nintedanib, and imatinib were thoroughly evaluated for activity against SARS-CoV-2 variants. Each drug exhibited antiviral activity, but with stark differences in potency, suggesting differences in host dependency for kinase targets. Importantly, for gilteritinib, the amount of compound needed to achieve 90% infection inhibition, at least in part involving blockade of spike protein-mediated viral entry and at concentrations not inducing phospholipidosis (PLD), approached a clinically achievable concentration. Knockout of AXL, a target of gilteritinib and nintedanib, impaired SARS-CoV-2 variant infectivity, supporting a role for AXL in SARS-CoV-2 infection and supporting further investigation of drug-mediated AXL inhibition as a COVID-19 treatment. This study supports further evaluation of AXL-targeting kinase inhibitors as potential antiviral agents and treatments for COVID-19. Additional mechanistic studies are needed to determine underlying differences in virus response.  相似文献   
92.
Many unbalanced large copy number variants reviewed in the paper are associated with syndromic orofacial clefts, including a 1.6 Mb deletion on chromosome 3q29. The current report presents a new family with this recurrent deletion identified via whole-exome sequencing and confirmed by array comparative genomic hybridization. The proband exhibited a more severe clinical phenotype than his affected mother, comprising right-sided cleft lip/alveolus and cleft palate, advanced dental caries, heart defect, hypospadias, psychomotor, and speech delay, and an intellectual disability. Data analysis from the 3q29 registry revealed that the 3q29 deletion increases the risk of clefting by nearly 30-fold. No additional rare and pathogenic nucleotide variants were identified that could explain the clefting phenotype and observed intrafamilial phenotypic heterogeneity. These data suggest that the 3q29 deletion may be the primary risk factor for clefting, with additional genomic variants located outside the coding sequences, methylation changes, or environmental exposure serving as modifiers of this risk. Additional studies, including whole-genome sequencing or methylation analyses, should be performed to identify genetic factors underlying the phenotypic variation associated with the recurrent 3q29 deletion.  相似文献   
93.
Anthocyanins belong to the flavonoid family and are ubiquitous in plants, especially in flower petals and fruit peels. We established that anthocyanins isolated from fruits of Aronia melanocarpa markedly inhibited the mutagenic activity of benzo(a)pyrene and 2-amino fluorene in the Ames test. In the Sister Chromatid Exchanges (SCEs) test with human blood-derived lymphocytes cultured in vitro, a significant decrease of SCEs frequency induced by benzo(a)pyrene was observed in the presence of anthocyanins. In the case of mitomycin C the effect of anthocyanins on SCEs frequency was smaller but still noticeable. Anthocyanins markedly inhibited the generation and release of superoxide radicals by human granulocytes. The results suggest that the antimutagenic influence of anthocyanins is exerted mainly by their free-radicals scavenging action as well as by the inhibition of enzymes activating promutagens and converting mutagens to the DNA-reacting derivatives. These preliminary data seem to be important in the aspect of a possible antimutagenic and anticarcinogenic potency of anthocyanins commonly present in fruits and vegetables.  相似文献   
94.
The concentrations of fibrinogen (Fb) and the activities of factor VII (F VIIC) and antithrombin III (AT III) both in men less than 55 years old with a history of myocardial infarction (MI) and with normolipemia (MI-NLP) or hyperlipoproteinemia (MI-HLP) and in their sons have been measured. A significantly higher levels of Fb were found in both MI groups. Significantly higher levels of F VIIC and AT III were found only in the MI-NLP group. No lipid or haemostatic disorders were noted in sons. Furthermore, a positive correlation between the level of F VIIC and triglycerides (TG) or total cholesterol (TCh) in the patients and sons was revealed. A positive correlation was found between: (a) Fb levels in MI-HLP patients and in their sons; (b) TG levels in MI-HLP patients and in their sons; and (c) AT III activity in MI patients and in their sons. Fibrinogen appears to be associated with ischemic heart disease more closely than factor VII, the latter being strongly linked with hypertriglyceridemia. Elevated activities of AT III may reflect the haemostatic response to the prothrombotic state in IHD on the one hand whereas they may contribute to the development of IHD on the other.  相似文献   
95.
Mercury concentration was determined in the caps and stalks of nine species of edible mushrooms collected at the area of Wieluńska Upland in district of Czestochowa in 1995-96. The mushroom species examined were such as: yellow-cracking bolete Xerocomus subtomentosus, brown birch scaber stalk Leccinum scabrum, slippery Jack Suillus luteus, larch bolete Suillus grevillei, gray knight-cap Tricholoma terreum, parasol mushroom Macrolepiota procera, horse mushroom Agaricus arvensis, fennel funnel cap Clitocybe odora, fairy-ring mushroom Marasmius oreades and tacky green brittle gills Russula aereuginea. The method of mercury measurement was cold-vapour atomic absorption spectroscopy (CV-AAS) after wet digestion of the samples with concentrated nitric acid in a whole glass system. The parasol mushroom and horse mushroom showed a highest mercury concentrations and contained, respectively, 4500 +/- 1700 and 4400 +/- 2400 ng/g dry wt in caps, and 2800 +/- 1300 and 2800 +/- 2100 ng/g dry wt in stalks. In the case of fennel funnel cap and fairy-ring mushroom the mean total mercury concentrations in caps was above 500 ng/g dry wt, and for other species were between 150 +/- 50 and 500 +/- 230 ng/g dry wt. The stalks of the mushroom species examined in all cases showed lower contamination with mercury than caps. The mean total mercury concentrations noted in caps and stalks of mushrooms examined were usually higher than was reported till now in the same species elsewhere in Poland, while a maximum values found in an individual fruiting bodies are within the range of the concentrations noted in specimens collected from an unpolluted areas.  相似文献   
96.
The aim of present study was to analyse possible myopathic changes in the muscles of manifesting carriers of Duchenne Muscular Dystrophy (DMD) using concentric needle emg and macroemg methods. Our material consisted of 10 manifesting carriers aged 9-52 (mean 30 years) and 20 healthy age-matched females. Concentric needle emg (CNEMG) and macroemg was performed in biceps brachii (BB) muscle in both groups: carriers and controls. Myopathic changes were observed in BB muscle in 5 of 10 manifesting carriers using CNEMG and in all cases (10 carriers) using macroemg method. Macro electrode, which reflects total motor unit activity, i.e., the total number and size of component muscle fibres, supplies information about early myogenic lesion of the muscle. Therefore the macroemg seems to be a sensitive and useful electrophysiological diagnostic method in carriers of DMD.  相似文献   
97.
Male Wistar rats were subjected to streptozotocin administration (85 mg/kg i.p.) and to cerebral air embolia with common carotids ligation. Electron microscope studies showed dark neurons, degeneration of endothelial cells and changes in basement membrane of brain capillaries, and changed astroglia in diabetic rats. Our results seem to support our previous findings in light microscopy and correspond with some others authors' suggestions that diabetes leads to chronic, generalized pathologic process in diabetic-rat brain, not-only dependent on vascular pathology, but which may be related to an oxidative/metabolic stress leading to a death of neurons in necrotic or apoptotic way.  相似文献   
98.
Forty-five children with primary brain tumors were evaluated by in vivo proton magnetic resonance spectroscopy (MRS) with the aim of detecting correlations between the obtained spectra and tumor malignancy and histology. All investigations were performed using a 1.5 T MR scanner (Picker) with point-resolved spectroscopic (PRESS) sequence (TR 1600 ms, TE 270 ms, NEX 256). Spectra were analyzed for N-acetylaspartate (NAA), choline containing-compounds (Cho), creatine and phosphocreatine (Cr) and lactate (Lac). The Cho/NAA ratio was the most useful parameter for differentiating between normal brain, benign and malignant tumors as well as discriminating the three main groups of pediatric brain tumors namely pilocytic astrocytoma, ependymoma and medulloblastoma. Proton MRS appears to be an important noninvasive technique in the differential diagnosis of pediatric brain tumors.  相似文献   
99.
100.
52 clinically definite multiple sclerosis (MS) patients were treated with subcutaneous injection of 5 mg 2-CDA in 5 consecutive days. The injection courses were repeated 6 times in one month interval. The MRI pattern and immunological markers were studied in serum and CSF before and after 6 months of treatment. The obtained results suggest that treatment with 2-CDA has not any significant effect on humoral immunological events in multiple sclerosis, what is in contrast to some normalization of cellular immunopathological processes.  相似文献   
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