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1.
The influence of feeding, egg load and stage of ovarian development on the sexual receptivity of some insect species has been reported. This work investigated the effects of different brewer's yeast concentrations in the diet offered to females of West Indian fruit fly, Anastrepha obliqua, on their sexual receptivity. Wild females were fed on artificial diets containing 2.0 g brewer's yeast per 100 mL of water (low‐yeast diet, LY diet), 6.5 g yeast per 100 mL of water (high‐yeast diet, HY diet) or only sucrose (Su diet) and then placed with the males. Female sexual receptivity tests were carried out in acrylic boxes in the laboratory under controlled conditions (temperature, humidity and light). Females fed on the HY diet were more sexually receptive to male courtship than the other females. Additionally, when fed on the same diet (HY diet), those females with higher egg load were more sexually receptive. The data suggest that the ingestion of a protein source is essential for increasing sexual receptivity and that egg load is the most important factor affecting sexual receptivity of A. obliqua females.  相似文献   
2.
Cardiotoxicity of the cancer therapeutic agent imatinib mesylate   总被引:17,自引:0,他引:17  
Imatinib mesylate (Gleevec) is a small-molecule inhibitor of the fusion protein Bcr-Abl, the causal agent in chronic myelogenous leukemia. Here we report ten individuals who developed severe congestive heart failure while on imatinib and we show that imatinib-treated mice develop left ventricular contractile dysfunction. Transmission electron micrographs from humans and mice treated with imatinib show mitochondrial abnormalities and accumulation of membrane whorls in both vacuoles and the sarco- (endo-) plasmic reticulum, findings suggestive of a toxic myopathy. With imatinib treatment, cardiomyocytes in culture show activation of the endoplasmic reticulum (ER) stress response, collapse of the mitochondrial membrane potential, release of cytochrome c into the cytosol, reduction in cellular ATP content and cell death. Retroviral gene transfer of an imatinib-resistant mutant of c-Abl, alleviation of ER stress or inhibition of Jun amino-terminal kinases, which are activated as a consequence of ER stress, largely rescues cardiomyocytes from imatinib-induced death. Thus, cardiotoxicity is an unanticipated side effect of inhibition of c-Abl by imatinib.  相似文献   
3.
The ACR-8-like group of C. elegans nicotinic acetylcholine receptor (nAChR) subunits contain unusual motifs in the ACh binding site and in the −1′ position of transmembrane region two (TM2). Using site-directed mutagenesis (SDM) we have introduced these motifs into chicken α7 as it has not been possible to express C. elegans nAChR in vitro. Oocytes expressing α7 with the C. elegans binding motif show a reduced affinity and efficacy for both ACh and nicotine. The blocking action of the anthelmintic drug levamisole is reduced. The TM2 motif resulted in a non-functional receptor. We conclude that the TM2 motif profoundly restricts cation movement through the α7 channel but does not confer anion permeability. The altered form of the ACh binding motif is likely to result in a receptor with altered pharmacology, adding potential functional diversity at synapses in the nervous system and neuromuscular junctions of C. elegans.  相似文献   
4.

Background

Cerebral palsy refers to permanent, mutable motor development disorders stemming from a primary brain lesion, causing secondary musculoskeletal problems and limitations in activities of daily living. The aim of the present study was to determine the effects of gait training combined with transcranial direct-current stimulation over the primary motor cortex on balance and functional performance in children with cerebral palsy.

Methods

A double-blind randomized controlled study was carried out with 24 children aged five to 12 years with cerebral palsy randomly allocated to two intervention groups (blocks of six and stratified based on GMFCS level (levels I-II or level III).The experimental group (12 children) was submitted to treadmill training and anodal stimulation of the primary motor cortex. The control group (12 children) was submitted to treadmill training and placebo transcranial direct-current stimulation. Training was performed in five weekly sessions for 2 weeks. Evaluations consisted of stabilometric analysis as well as the administration of the Pediatric Balance Scale and Pediatric Evaluation of Disability Inventory one week before the intervention, one week after the completion of the intervention and one month after the completion of the intervention. All patients and two examiners were blinded to the allocation of the children to the different groups.

Results

The experimental group exhibited better results in comparison to the control group with regard to anteroposterior sway (eyes open and closed; p<0.05), mediolateral sway (eyes closed; p<0.05) and the Pediatric Balance Scale both one week and one month after the completion of the protocol.

Conclusion

Gait training on a treadmill combined with anodal stimulation of the primary motor cortex led to improvements in static balance and functional performance in children with cerebral palsy.

Trial Registration

Ensaiosclinicos.gov.br/RBR-9B5DH7  相似文献   
5.
Although yeasts belonging to the genus Candida are frequently seen as commensals in the oral cavity, they possess virulence attributes that contribute for pathogenicity. The aims of the present study were to study the prevalence of Candida spp. isolated from the oral cavity of renal transplant recipients and to analyze strains virulence factors. We isolated a total of 70 Candida strains from 111 transplant recipients, and Candida albicans was the most prevalent species (82.86 %). Oral candidiasis was diagnosed in 14.4 % kidney transplant patients, while 11 isolates (15.7 %) corresponded to non-Candida albicans Candida (NCAC) species. C. albicans adhered to a higher extension than NCAC strains. Some isolates of Candida tropicalis were markedly adherent to human buccal epithelial cells and highly biofilm-forming strains. Regarding proteinase activity, Candida orthopsilosis was more proteolytic than Candida metapsilosis. Candida glabrata and Candida dubliniensis showed very low ability to form biofilm on polystyrene microtiter plates. We have demonstrated here diverse peculiarities of different Candida species regarding the ability to express virulence factors. This study will contribute for the understanding of the natural history and pathogenesis of yeasts belonging to the genus Candida in the oral cavity of patients who were submitted to kidney transplant and are under immunosuppressive therapies.  相似文献   
6.
7.
Mother-to-child transmission (MTCT) of HIV-1 has been significantly reduced with the use of antiretroviral therapies, resulting in an increased number of HIV-exposed uninfected infants. The consequences of HIV infection on the innate immune system of both mother-newborn are not well understood. In this study, we analyzed peripheral blood and umbilical cord blood (CB) collected from HIV-1-infected and uninfected pregnant women. We measured TNF-α, IL-10 and IFN-α secretion after the stimulation of the cells with agonists of both extracellular Toll-like receptors (TLRs) (TLR2, TLR4 and TLR5) and intracellular TLRs (TLR7, TLR7/8 and TLR9). Moreover, as an indicator of the innate immune response, we evaluated the responsiveness of myeloid dendritic cells (mDCs) and plasmacytoid DCs (pDCs) to TLRs that are associated with the antiviral response. Our results showed that peripheral blood mononuclear cells (PBMCs) from HIV-1-infected mothers and CB were defective in TNF-α production after activation by TLR2, TLR5, TLR3 and TLR7. However, the TNF-α response was preserved after TLR7/8 (CL097) stimulation, mainly in the neonatal cells. Furthermore, only CL097 activation was able to induce IL-10 and IFN-α secretion in both maternal and CB cells in the infected group. An increase in IFN-α secretion was observed in CL097-treated CB from HIV-infected mothers compared with control mothers. The effectiveness of CL097 stimulation was confirmed by observation of similar mRNA levels of interferon regulatory factor-7 (IRF-7), IFN-α and TNF-α in PBMCs of both groups. The function of both mDCs and pDCs was markedly compromised in the HIV-infected group, and although TLR7/TLR8 activation overcame the impairment in TNF-α secretion by mDCs, such stimulation was unable to reverse the dysfunctional type I IFN response by pDCs in the HIV-infected samples. Our findings highlight the dysfunction of innate immunity in HIV-infected mother-newborn pairs. The activation of the TLR7/8 pathway could function as an adjuvant to improve maternal-neonatal innate immunity.  相似文献   
8.
Pressed grape pomace obtained from the wine production of Cabernet sauvignon (Vitis vinifera) vintage was dried until 9.8% moisture content, ground and submitted to extraction of soluble components from different extraction techniques. Low pressure extractions were performed with ethanol maceration followed by fractionation with n-hexane, dichloromethane, butanol and ethyl acetate. These solvents were furthermore applied for soxhlet extraction. Supercritical fluid extraction (SFE) was also performed to obtain grape pomace extracts by using pure CO(2) and CO(2) with ethanol as co-solvent in concentrations of 10, 15 and 20%w/w. The operating condition used in high pressure extractions was 150bar and 40 degrees C. The antioxidant activity of the grape pomace extracts was determined considering the free radical scavenging assay using 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and was correlated with the total phenol content determined according to the Folin-Ciocalteu method. The results obtained in DPPH tests indicate the highest antioxidant activity of 96.6+/-0.3%AA, with an IC(50) value of 13+/-1, for the extracts obtained with ethyl acetate in solid-liquid extraction. The highest yield values were achieved in soxhlet extraction with ethanol (13.2%w/w) and with butanol (12.2%w/w), and also by SFE with 15% ethanol (9.2%w/w). The lipophilic composition of grape pomace extracts was evaluated by gas chromatography-mass spectrometry with the identification of components like linoleic acid and ethyl linoleate, with important therapeutic activities.  相似文献   
9.
BACKGROUND: Adenoviral gene transfer has been shown to be effective in cardiac myocytes in vitro and in vivo. A major limitation of myocardial gene therapy is the extracardiac transgene expression. METHODS: To minimize extracardiac gene expression, we have constructed a tissue-specific promoter for cardiac gene transfer, namely, the 250-bp fragment of the myosin light chain-2v (MLC-2v) gene, which is known to be expressed in a tissue-specific manner in ventricular myocardium followed by a luciferase (luc) reporter gene (Ad.4 x MLC250.Luc). Rat cardiomyocytes, liver and kidney cells were infected with Ad.4 x MLC.Luc or control vectors. For in vivo testing, Ad.4 x MLC250.Luc was injected into the myocardium or in the liver of rats. Kinetics of promoter activity were monitored over 8 days using a cooled CCD camera. RESULTS: In vitro: By infecting hepatic versus cardiomyocyte cells, we found that the promoter specificity ratio (luc activity in cardiomyocytes per liver cells) was 20.4 versus 0.9 (Ad.4 x MLC250.Luc vs. Ad.CMV). In vivo: Ad.4 x MLC250.Luc significantly reduced luc activity in liver (38.4-fold), lung (16.1-fold), and kidney (21.8-fold) versus Ad.CMV (p =.01); whereas activity in the heart was only 3.8-fold decreased. The gene expression rate of cardiomyocytes versus hepatocytes was 7:1 (Ad.4 x MLC.Luc) versus 1:1.4 (Ad.CMV.Luc). DISCUSSION: This new vector may be useful to validate therapeutic approaches in animal disease models and offers the perspective for selective expression of therapeutic genes in the diseased heart.  相似文献   
10.
Background: Transcranial direct current stimulation (tDCS) has emerged as a promising therapeutic tool to improve balance and optimize rehabilitation strategies. However, current literature shows the methodological heterogeneity of tDCS protocols and results, hindering any clear conclusions about the effects of tDCS on postural control.

Objective: Evaluate the effectiveness of tDCS on postural control, and identify the most beneficial target brain areas and the effect on different populations.

Methods: Two independent reviewers selected randomized tDCS clinical-trials studies from PubMed, Scopus, Web of Science, and reference lists of retrieved articles published between 1998 and 2017. Most frequently reported centre of pressure (COP) variables were selected for meta-analysis. Other postural control outcomes were discussed in the review.

Results: Thirty studies were included in the systematic review, and 11 were submitted to a meta-analysis. A reduction of COP displacement area has been significantly achieved by tDCS, evidencing an improvement in balance control. Individuals with cerebral palsy (CP) and healthy young adults are mostly affected by stimulation. The analysis of the impact of tDCS over different brain areas revealed a significant effect after primary motor cortex (M1) stimulation, however, with no clear results after cerebellar stimulation due to divergent results among studies.

Conclusions: tDCS appears to improve balance control, more evident in healthy and CP subjects. Effects are observed when primary MI is stimulated. Cerebellar stimulation should be better investigated.  相似文献   

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