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11.
Transport of metabolites across the mitochondrial inner membrane is highly selective, thereby maintaining the electrochemical proton gradient that functions as the main driving force for cellular adenosine triphosphate synthesis. Mitochondria import many preproteins via the presequence translocase of the inner membrane. However, the reconstituted Tim23 protein constitutes a pore remaining mainly in its open form, a state that would be deleterious in organello. We found that the intermembrane space domain of Tim50 induced the Tim23 channel to close. Presequences overcame this effect and activated the channel for translocation. Thus, the hydrophilic cis domain of Tim50 maintains the permeability barrier of mitochondria by closing the translocation pore in a presequence-regulated manner.  相似文献   
12.
Both resiniferatoxin (RTX) and tetrodotoxin (TTX) have been reported to be effective in several clinical trials aiming to cure urinary bladder dysfunction. The goal of this experiment was to study the effect of intravesical administration of RTX and TTX on the chemical coding of paracervical ganglion (PCG) neurons that supply the urinary bladder in pigs. The vasoactive intestinal peptide (VIP) and the opioid family member Leu5-enkephalin (LENK) are both known for their regulatory effects in the function of the porcine genitourinary tract. The PCG neurons innervating the urinary bladder were identified by application of the retrograde tracer Fast Blue (FB), injected into the bladder wall prior to intravesical RTX or TTX administration. Immunocytochemical detection of LENK and VIP expression in the FB-labelled perikarya revealed that in the control group 25.15% of the FB-positive PCG neurons contained LENK, and 9.22% of them expressed VIP. Intravesical infusion of RTX resulted in an increase in the number of LENKIR neurons to 48.19% and VIP-IR perikarya to 11.25%. Optional treatment with TTX induced increase of LENK-IR neurons up to 81.67% and VIP-IR population to 16.46% of the FB-positive PCG cells. The present results show that both neurotoxins affect the chemical coding of PCG nervous cells supplying the porcine urinary bladder and that they stimulate both LENK and VIP expression. Furthermore, the results indicate a possible involvement of LENK and VIP neurons in the mechanisms of action of RTX and TTX in the therapy of overactive bladder disorder.  相似文献   
13.
In both the horse and the man, nutritional ergogenic aids have been used to improve physical ability in conjunction with an appropriate training regimen. Although training increases physical condition, the ease of taking a nutritional additive to improve training results explains the demand for supplementation, which may increase mechanical energy of work, delay onset of fatigue, or improve neuromuscular coordination. The purpose of this study was to determine the effects of oral supplementation of β-hydroxy-β-methylbutyrate (HMB) and γ-oryzanol (GO) on indices of exercise-induced muscle damage in Thoroughbred race horses. In this 32-week study, the horses were assigned to either a placebo, GO (3.0 g/d), HMB (15 g/d), or GO and HMB treatment groups. The supplements were administered for the first 16 weeks of the study during the training period before the racing season began. Blood samples were taken at baseline, and then during training, before exercise, immediately after exercise, and 30 minutes after exercise. Heart rate and speed were monitored in each exercise session. Hematocrit, glucose, lactate (LA), creatine phosphokinase, and aspartate aminotransferase were measured before and after each exercise session. Analysis of variance showed a significantly greater increase in postexercise creatine kinase activity in placebo-supplemented group than in the other treatment groups, both in the training period and during the racing seasons (P < .05). Blood LA was higher immediately after exercise in the placebo group compared with the supplemented groups. In conclusion, supplementation with HMB and GO resulted in decreased creatine kinase and LA after exercise. These findings support the hypothesis that HMB and GO supplementation helps to prevent exercise-induced muscle damage.  相似文献   
14.
Biotic interactions affect the impact of potential plant growth promoting microorganisms in the rhizosphere, but their magnitude and fundamentals are often hardly known. In a pot experiment, two physiologically different strains of the ectomycorrhizal fungus Paxillus involutus (GUL and FRA) were tested separately and in combination with associated bacteria (Sphingomonas paucimobilis 1 L, Ralstonia pickettii 16 B, Sphingomonas sp. 23 L) on their effects on the growth of willows (Salix viminalis). Both P. involutus strains significantly increased the growth of the willows compared with non-inoculated plants, but the magnitude of this effect was significantly affected by the fungal strain. The P. involutus strain GUL with higher synthesis of auxin-like substances, acid phosphatases, siderophores and faster utilisation of yeast extract in vitro increased the willow growth in situ more effectively than strain FRA. Additionally, dual inoculation with the P. involutus strains GUL and FRA in combination with the associated bacteria promoted the willow growth, especially the combination with S. paucimobilis 1 L. This bacterial strain used effectively C sources which are common components of plant root exudates, e.g. glucose, sucrose, maltose and mannose as well as compounds synthesized by fungi, e.g. trehalose in vitro. We conclude that the analyses of fungal metabolites and of C source use of associated bacteria can successfully contribute to accelerate the selection of capable plant growth promoting combinations.  相似文献   
15.
The behavior of 2 spectacled bears (Tremarctos ornatus) was studied at Wroclaw Zoo (Poland), where they were housed in a very small outdoor enclosure, and then in a separate study after transfer to a large naturalistic exhibit at Chester Zoo (CZ; United Kingdom). The studies combine to form an opportunistic “experiment” on the effects of transfer on zoo animals. This situation provided a unique opportunity for a closer investigation of known behavior problems and their causation. In part 1 of the study, at Wroclaw Zoo, the median amount of time devoted to stereotypical movements was 57 min/h. After the move to CZ, immediate changes in behavior were reported in 1 individual, for whom the stereotypy was eradicated. The other bear continued performing repetitive behavior of high intensity and only used a small area of the large enclosure. Signs of dental problems were subsequently observed in both bears, and so a dental examination was carried out, resulting in multiple extractions. After treatment, the amount of time that the bear with ongoing behavior problems spent stereotyping reduced significantly, and foraging increased. Our data suggest the bears' stereotypic behavior occurred not only in response to an understimulating environment in their old enclosure but also perhaps in association with medical conditions in one of the bears. Although other factors could have contributed to the observed reduction in stereotypy, it is clear that further investigation is needed into the effects of pain and physical condition on stereotypy in animals.  相似文献   
16.
Chemical analyses and mass spectrometry were used to study the structure of the lipopolysaccharide (LPS) isolated from Aeromonas bestiarum strain K296, serotype O18. ESI-MS revealed that the most abundant A. bestiarum LPS glycoforms have a hexa-acylated or tetra-acylated lipid A with conserved architecture of the backbone, consisting of a 1,4′-bisphosphorylated β-(1→6)-linked d-GlcN disaccharide with an AraN residue as a non-stoichiometric substituent and a core oligosaccharide composed of Kdo1Hep6Hex1HexN1P1. 1D and 2D NMR spectroscopy revealed that the O-specific polysaccharide (OPS) of A. bestiarum K296 consists of a branched tetrasaccharide repeating unit containing two 6-deoxy-l-talose (6dTalp), one Manp and one GalpNAc residues; thus, it is similar to that of the OPS of A. hydrophila AH-3 (serotype O34) in both the sugar composition and the glycosylation pattern. Moreover, 3-substituted 6dTalp was 2-O-acetylated and additional O-acetyl groups were identified at O-2 and O-4 (or O-3) positions of the terminal 6dTalp. Western blots with polyclonal rabbit sera showed that serotypes O18 and O34 share some epitopes in the LPS. The very weak reaction of the anti-O34 serum with the O-deacylated LPS of A. bestiarum K296 might have been due to the different O-acetylation pattern of the terminal 6dTalp. The latter suggestion was further confirmed by NMR.  相似文献   
17.
Journal of Soils and Sediments - The objective of this study was to evaluate the mutual relations between the soil organic matter (SOM) fractions: fulvic acids (FA), humic acids (HA), humins (HN),...  相似文献   
18.
Plant Foods for Human Nutrition - This study analysed fruits of cranberry cultivars: Ben Lear, Bergman, Early Richard, Pilgrim and Stevens and compared them with wild-grown cranberry fruits. The...  相似文献   
19.
Nanomaterials and particularly silver nanoparticles (AgNPs) have increased great interest in many fields of science. The element may affect plant growth and development but so far research studies have been scarce and their results disparate. Tulip is one of the most important ornamental plants and its production technology is constantly being improved. The aim of this study was to investigate the effects of AgNPs on growth and yield attributes of tulip cv. ‘Pink Impression’. Before planting, the tulip ‘Pink Impression’ bulbs were soaked in the following concentrations of AgNPs: 25, 50, 100 and 150?mg?L-1. Control bulbs were soaked in deionized water. The plants were forced in a greenhouse for two growing seasons. The tulips treated with 100?mg?L?1 AgNPs flowered earlier, had longer cut-flower stem, larger petals, greater stem diameter and cut-flower fresh weight. Moreover, at this concentration of AgNPs, they showed increased leaf greenness index (SPAD), stomatal conductance, root fresh weight, root length and produced daughter bulbs of the greatest weight. The study outcomes indicate that AgNPs may be used as plant growth promoters in horticulture.  相似文献   
20.
Background: Long non-coding RNAs(lncRNAs) may regulate gene expression in numerous biological processes including cellular response to xenobiotics.The exposure of living organisms to 2,3,7,8-tetrachlorodibenzo-p-dioxin(TCDD),a persistent environmental contaminant,results in reproductive defects in many species including pigs.The aims of the study were to identify and characterize lncRNAs in porcine granulosa cells as well as to examine the effects of TCDD on the lncRNA expression profile in the cells.Results: One thousand six hundred sixty-six lncRNAs were identified and characterized in porcine granulosa cells.The identified lncRNAs were found to be shorter than mRNAs.In addition,the number of exons was lower in lncRNAs than in m RNAs and their exons were longer.TCDD affected the expression of 22 lncRNAs(differentially expressed lncRNAs [DELs]; log2 fold change ≥ 1,P-adjusted 0.05) in the examined cells.Potential functions of DELs were indirectly predicted via searching their target cis-and trans-regulated protein-coding genes.The coexpression analysis revealed that DELs may influence the expression of numerous genes,including those involved in cellular response to xenobiotics,dioxin metabolism,endoplasmic reticulum stress and cell proliferation.Aryl hydrocarbon receptor(AhR) and cytochrome P450 1 A1(CYP1 A1) were found among the trans-regulated genes.Conclusions: These findings indicate that the identified lncRNAs may constitute a part of the regulatory mechanism of TCDD action in granulosa cells.To our knowledge,this is the first study describing lncRNAs in porcine granulosa cells as well as TCDD effects on the lncRNA expression profile.These results may trigger new research directions leading to better understanding of molecular processes induced by xenobiotics in the ovary.  相似文献   
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