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Ischemic acute renal failure (ARF) is a highly complex disorder involving renal vasoconstriction, filtration failure, tubular obstruction, tubular backleak and generation of reactive oxygen species. Due to this complexity, the aim of our study was to explore effects of Angiotensin II type 1 receptor (AT1R) blockade on kidney structure and function, as well as oxidative stress in spontaneously hypertensive rats (SHR) after renal ischemia reperfusion injury. Experiments were performed on anaesthetized adult male SHR in the model of ARF with 40 minutes clamping the left renal artery. The right kidney was removed and 40 minutes renal ischemia was performed. Experimental groups received AT1R antagonist (Losartan) or vehicle (saline) in the femoral vein 5 minutes before, during and 175 minutes after the period of ischemia. Biochemical parameters were measured and kidney specimens were collected 24h after reperfusion. ARF significantly decreased creatinine and urea clearance, increased LDL and lipid peroxidation in plasma. Treatment with losartan induced a significant increase of creatinine and urea clearance, as well as HDL. Lipid peroxidation in plasma was decreased and catalase enzyme activity in erythrocytes was increased after losartan treatment. Losartan reduced cortico-medullary necrosis and tubular dilatation in the kidney. High expression of pro-apoptotic Bax protein in the injured kidney was downregulated after losartan treatment. Our results reveal that angiotensin II (via AT1R) mediates the most postischemic injuries in hypertensive kidney through oxidative stress enhancement. Therefore, blockade of AT1R may have beneficial effects in hypertensive patients who have developed ARF.  相似文献   
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The advent of publishing anonymized call detail records opens the door for temporal and spatial human dynamics studies. Such studies, besides being useful for creating universal models for mobility patterns, could be also used for creating new socio-economic proxy indicators that will not rely only on the local or state institutions. In this paper, from the frequency of calls at different times of the day, in different small regional units (sub-prefectures) in Côte d''Ivoire, we infer users'' home and work sub-prefectures. This division of users enables us to analyze different mobility and calling patterns for the different regions. We then compare how those patterns correlate to the data from other sources, such as: news for particular events in the given period, census data, economic activity, poverty index, power plants and energy grid data. Our results show high correlation in many of the cases revealing the diversity of socio-economic insights that can be inferred using only mobile phone call data. The methods and the results may be particularly relevant to policy-makers engaged in poverty reduction initiatives as they can provide an affordable tool in the context of resource-constrained developing economies, such as Côte d''Ivoire''s.  相似文献   
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Differentiation of cancer cells entails the reversion of phenotype from malignant to the original. The conversion to cell type characteristic for another tissue is named transdifferentiation. Differentiation/transdifferentiation of malignant cells in high grade tumor mass could serve as a nonaggressive approach that potentially limits tumor progression and augments chemosensitivity. While this therapeutic strategy is already being used for treatment of hematological cancers, its feasibility for solid malignancies is still debated. We will presently discuss the natural compounds that show these properties, with focus on anthraquinones from Aloe vera, Senna, Rheum sp. and hop derived prenylflavonoids.  相似文献   
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Kv1.3 is a voltage gated potassium channel that has been implicated in pathophysiology of multiple sclerosis (MS). In the present study we investigated temporal and cellular expression pattern of this channel in the lumbar part of spinal cords of animals with experimental autoimmune encephalomyelitis (EAE), animal model of MS. EAE was actively induced in female Dark Agouti rats. Expression of Kv1.3 was analyzed at different time points of disease progression, at the onset, peak and end of EAE. We here show that Kv1.3 increased by several folds at the peak of EAE at both gene and protein level. Double immunofluorescence analyses demonstrated localization of Kv1.3 on activated microglia, macrophages, and reactive astrocytes around inflammatory lesions. In vitro experiments showed that pharmacological block of Kv1.3 in activated astrocytes suppresses the expression of proinflammatory mediators, suggesting a role of this channel in inflammation. Our results support the hypothesis that Kv1.3 may be a therapeutic target of interest for MS and add astrocytes to the list of cells whose activation would be suppressed by inhibiting Kv1.3 in inflammatory conditions.  相似文献   
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Sponges (phylum Porifera) live in a symbiotic relationship with microorganisms, primarily bacteria. Until now, molecular proof for the capacity of sponges to recognize fungi in the surrounding aqueous milieu has not been available. Here we demonstrate, for the demosponge Suberites domuncula (Porifera, Demospongiae, Hadromerida), a cell surface receptor that recognizes (1-->3)-beta-D-glucans, e.g. curdlan or laminarin. This receptor, the (1-->3)-beta-D-glucan-binding protein, was identified and its cDNA analysed. The gene coding for the 45 kDa protein was found to be upregulated in tissue after incubation with carbohydrate. Simultaneously with the increased expression of this gene, two further genes showed an elevated steady state level of expression; one codes for a fibrinogen-like protein and the other for the epidermal growth factor precursor. Expression of the (1-->3)-beta-D-glucan-binding protein and the fibrinogen-like protein occurred in cells on the sponge surface, in the pinacoderm. By Western blotting, the product of the fibrinogen-like protein gene was identified, the recombinant protein isolated, and antibodies raised to this protein. Their application revealed that a 5 kDa factor is produced, which is apparently processed from the 77 kDa epidermal growth factor precursor. Finally, we provided evidence that a tyrosine kinase pathway is initiated in response to exposure to D-glucan; its phosphorylation activity could be blocked by aeroplysinin. In turn, the increased expression of the downstream genes was suppressed. We conclude that sponges possess a molecular mechanism for recognizing fungi via the d-glucan carbohydrates on their surfaces.  相似文献   
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COVID-19 disease has been a problem in today’s society, which has worldwide effects on different areas, especially on the economy; also, from a health perspective, the disease affects the daily life quality. Physical activity is one major positive factor with regard to enhancing life quality, as it can improve the whole psychological, social, and physical health conditions. Current measures such as social distancing are focused on preventing the viral spread. However, the consequences on other areas are yet to be investigated. Elderly, people with chronic diseases, obese, and others benefit largely from exercise from the perspective of improved health, and preventive measures can drastically improve daily living. In this article, we elaborate the effects of exercise on the immune system and the possible strategies that can be implemented toward greater preventive potential.  相似文献   
69.
Cerebral palsy (CP) is a nonprogressive motor disorder caused by white matter damage in the developing brain. Recent epidemiological and clinical data suggest intrauterine infection/inflammation as the most common cause of preterm delivery and neonatal complications, including CP. Cyclooxygenases are key enzymes in the conversion of arachidonic acid to prostaglandins. The COX family consists of two isoforms, COX-1 and COX-2. In the brain, COX-2 is constitutively expressed at high levels on pyramidal neurons, while COX-1 is predominantly expressed by microglia and can be upregulated in pathological conditions, such as infection, ischemia and traumatic brain injury. Single nucleotide polymorphisms in the COX-1 and COX-2 gene could have profound effects on COX-1 and COX-2 expression and, directly or indirectly, influence the pathogenesis, development and severity of CP. In this study we investigated the association between single nucleotide polymorphisms of the COX-1 and COX-2 gene and susceptibility to cerebral palsy in very preterm infants. The results of our study showed the association between COX-1 high expression genotype (?842 AA) and COX-1 high expression allele ?842A and risk of CP in infants with cystic periventricular leucomalacia (cPVL). Our results support an important role of COX-1 enzyme on microglial activation during neuroinflammation resulting in huge neuroinflammatory response and the proinflammatory mediator overproduction, with the serious white matter damage and CP development as a consequence.  相似文献   
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