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31.
Acinetobacter baumannii causes serious infections especially in immunocompromised and/or hospitalized patients. Several A. baumannii strains are multidrug resistant and infect wounds, bones, and the respiratory tract. Current studies are focused on finding new effective agents against A. baumannii. Phage therapy is a promising means to fight this bacterium and many studies on procuring and applying new phages against A. baumannii are currently being conducted. As shown in animal models, phages against multidrug-resistant A. baumannii may control bacterial infections caused by this pathogen and may be a real hope to solve this dangerous health problem. 相似文献
32.
Chung Kwon Kim Ji-Yoon Hwang Tae Hee Hong Du Man Lee Kyunghoon Lee Hyun Nam Kyeung Min Joo 《BMB reports》2022,55(7):336
Narrowing of arteries supplying blood to the limbs provokes critical hindlimb ischemia (CLI). Although CLI results in irreversible sequelae, such as amputation, few therapeutic options induce the formation of new functional blood vessels. Based on the proangiogenic potentials of stem cells, in this study, it was examined whether a combination of dental pulp stem cells (DPSCs) and human umbilical vein endothelial cells (HUVECs) could result in enhanced therapeutic effects of stem cells for CLI compared with those of DPSCs or HUVECs alone. The DPSCs+ HUVECs combination therapy resulted in significantly higher blood flow and lower ischemia damage than DPSCs or HUVECs alone. The improved therapeutic effects in the DPSCs+ HUVECs group were accompanied by a significantly higher number of microvessels in the ischemic tissue than in the other groups. In vitro proliferation and tube formation assay showed that VEGF in the conditioned media of DPSCs induced proliferation and vessel-like tube formation of HUVECs. Altogether, our results demonstrated that the combination of DPSCs and HUVECs had significantly better therapeutic effects on CLI via VEGF-mediated crosstalk. This combinational strategy could be used to develop novel clinical protocols for CLI proangiogenic regenerative treatments. 相似文献
33.
Woo HN Baik SH Park JS Gwon AR Yang S Yun YK Jo DG 《Biochemical and biophysical research communications》2011,(1):402-15
Accumulation of amyloid-β (Aβ) is widely accepted as the key instigator of Alzheimer’s disease (AD). The proposed mechanism is that accumulation of Aβ results in inflammatory responses, oxidative damages, neurofibrillary tangles and, subsequently, neuronal/synaptic dysfunction and neuronal loss. Given the critical role of Aβ in the disease process, the proteases that produce this peptide are obvious targets. The goal would be to develop drugs that can inhibit the activity of these targets. Protease inhibitors have proved very effective for treating other disorders such as AIDS and hypertension. Mutations in APP (amyloid-β precursor protein), which flanks the Aβ sequence, cause early-onset familial AD, and evidence has pointed to the APP-to-Aβ conversion as a possible therapeutic target. Therapies aimed at modifying Aβ-related processes aim higher up the cascade and are therefore more likely to be able to alter the progression of the disease. However, it is not yet fully known whether the increases in Aβ levels are merely a result of earlier events that were already causing the disease. 相似文献
34.
Ana O. Fagundes Maira R. Aguiar Claudia S. Aguiar Giselli Scaini Monique U. Sachet Nayara M. Bernhardt Gislaine T. Rezin Samira S. Valvassori João Quevedo Emilio L. Streck 《Neurochemical research》2010,35(11):1675-1680
Methylphenidate is commonly used for the treatment of attention deficit/hyperactivity disorder. There are still few works
regarding the effects of methylphenidate on brain energy metabolism. Thus, in the present study we evaluated the effect of
chronic administration of methylphenidate on the activities of mitochondrial respiratory chain complexes I and III in the
brain of young rats. The effect of acute administration of methylphenidate on mitochondrial respiratory chain complexes I,
II, III and IV in the brain of young rats was also investigated. For acute administration, a single injection of methylphenidate
was given to rats on postnatal day 25. For chronic administration, methylphenidate injections were given starting at postnatal
day 25 once daily for 28 days. Our results showed that complexes I and III were not affected by chronic administration of
methylphenidate. Moreover, the acute administration of methylphenidate decreased complex I activity in cerebellum and prefrontal
cortex, whereas complexes II, III and IV were not altered. 相似文献
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36.
A survey on attitudes toward large carnivores was conducted in a representative sample of the Norwegian population (n = 3134). People were asked about the acceptability of carnivores living in remote wilderness, close to where people live, killing livestock, killing pets, or threatening humans. Large differences in acceptability appeared across the five situations. Wolves and bears were less acceptable than lynx and wolverines when observed close to where people live. Negative associations were found between acceptability and lack of personal control, economic loss, and respondents' age. Acceptability was higher among males than among females, and higher among urban than among rural residents. The results showed that general measures of attitudes alone toward large carnivores were of limited value in wildlife management. The situational and social specificity of these attitudes should be given more attention. 相似文献
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40.
María Capa João Miguel de Matos Nogueira Maíra Cappellani Silva Rossi 《Journal of morphology》2011,272(3):302-319
Fan worms (Sabellidae) possess paired modified prostomial structures at the base of the radiolar crown, dorso‐lateral to the mouth, called dorsal lips. The dorsal lips are involved in the sorting of particles collected by the radiolar crown. The range of variation in the morphology of dorsal lips is extensive, and probably this is not only due to adaptations to different environments and feeding preferences but also due to phylogenetic constraints. In this study, we describe and compare the morphology of dorsal lips in a range of sabellid taxa based on histological cross‐sections of these structures, and compare our data and terminology with those of previous studies. Dorsal lips are maintained erect in most taxa by a modified radiole fused to them known as dorsal radiolar appendage. We suggest that dorsal radiolar appendages with an internal supporting axis (cellular or acellular) and probably also the ventral lips are synapomorphies of the family. J. Morphol., 2011. © 2010 Wiley‐Liss, Inc. 相似文献