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21.
In the current study, a series of pyrazole-sulfonamide derivatives (2–14) were synthesized, characterized, and the inhibition effects of the derivatives on human carbonic anhydrases (hCA I and hCA II) were investigated as in vitro. Structures of these sulfonamides were confirmed by FT-IR, 1H NMR, 13C NMR and LC–MS analysis. 1H NMR and 13C NMR revealed the tautomeric structures. hCA I and hCA II isozymes were purified from human erythrocytes and inhibitory effects of newly synthesized sulfonamides on esterase activities of these isoenzymes have been studied. The Ki values of compounds were 0.062–1.278 μM for hCA I and 0.012–0.379 μM for hCA II. The inhibition effects of 7 for hCA I and 4 for hCA II isozymes were almost in nanomolar concentration range.  相似文献   
22.
Highlights? Cardiac laterality involves Nodal modulating an antimotogenic Bmp activity ? The Nodal target Hyaluronan synthase 2 unilaterally dampens Bmp signaling activity ? Nonmuscle myosin II is positively regulated by Bmp within cardiac tissue ? High levels of nonmuscle myosin II activity reduce cardiac cell motility  相似文献   
23.
Herein, we have identified cross-talk between the Hippo and fibroblast growth factor receptor (FGFR) oncogenic signaling pathways in cholangiocarcinoma (CCA). Yes-associated protein (YAP) nuclear localization and up-regulation of canonical target genes was observed in CCA cell lines and a patient-derived xenograft (PDX). Expression of FGFR1, -2, and -4 was identified in human CCA cell lines, driven, in part, by YAP coactivation of TBX5. In turn, FGFR signaling in a cell line with minimal basal YAP expression induced its cellular protein expression and nuclear localization. Treatment of YAP-positive CCA cell lines with BGJ398, a pan-FGFR inhibitor, resulted in a decrease in YAP activation. FGFR activation of YAP appears to be driven largely by FGF5 activation of FGFR2, as siRNA silencing of this ligand or receptor, respectively, inhibited YAP nuclear localization. BGJ398 treatment of YAP-expressing cells induced cell death due to Mcl-1 depletion. In a YAP-associated mouse model of CCA, expression of FGFR 1, 2, and 4 was also significantly increased. Accordingly, BGJ398 treatment was tumor-suppressive in this model and in a YAP-positive PDX model. These preclinical data suggest not only that the YAP and Hippo signaling pathways culminate in an Mcl-1-regulated tumor survival pathway but also that nuclear YAP expression may be a biomarker to employ in FGFR-directed therapy.  相似文献   
24.
25.

Background

In Chad, several species of tsetse flies (Genus: Glossina ) transmit African animal trypanosomoses (AAT), which represents a major obstacle to cattle rearing, and sleeping sickness, which impacts public health. After the failure of past interventions to eradicate tsetse, the government of Chad is now looking for other approaches that integrate cost-effective intervention techniques, which can be applied by the stake holders to control tsetse-transmitted trypanosomoses in a sustainable manner. The present study thus attempted to assess the efficacy of restricted application of insecticides to cattle leg extremities using footbaths for controlling Glossina m. submorsitans, G . tachinoides and G . f . fuscipes in southern Chad.

Methodology/Principal Findings

Two sites were included, one close to the historical human African trypanosomiasis (HAT) focus of Moundou and the other to the active foci of Bodo and Moissala. At both sites, a treated and an untreated herd were compared. In the treatment sites, cattle were treated on a regular basis using a formulation of deltamethrin 0.005% (67 to 98 cattle were treated in one of the sites and 88 to 102 in the other one). For each herd, tsetse densities were monthly monitored using 7 biconical traps set along the river and beside the cattle pen from February to December 2009. The impact of footbath treatment on tsetse populations was strong (p < 10-3) with a reduction of 80% in total tsetse catches by the end of the 6-month footbath treatment.

Conclusions/Significance

The impact of footbath treatment as a vector control tool within an integrated strategy to manage AAT and HAT is discussed in the framework of the “One Health” concept. Like other techniques based on the treatment of cattle, this technology should be used under controlled conditions, in order to avoid the development of insecticide and acaricide resistance in tsetse and tick populations, respectively.  相似文献   
26.
Chalcone synthase (CHS) genes in Petunia hybrida comprise a multigene family containing at least 7 complete members in the strain Violet 30 (V30). Based on a high sequence homology in both coding and non-coding sequence, a number of CHS genes can be placed into two subfamilies. By restriction fragment length polymorphism (RFLP) analysis it was shown that both chromosomes II and V carry one of these subfamilies, in addition to the other CHS genes identified so far. Members of a subfamily were found to be closely linked genetically. Analysis of the Petunia species that contributed to the hybrid nature of P. hybrida (P. axillaris, P. parodii, P. inflata and P. violacea) shows that none of the CHS gene clusters is specific for either one of the parents and therefore did not arise as a consequence of the hybridization. The number of CHS genes within a subfamily varies considerably among these Petunia species. From this we infer that the CHS subfamilies arose from very recent gene duplications.  相似文献   
27.
Ziziphora tenuior L. (Lamiaceae) is an aromatic herb used for its medicinal values against fungi, bacteria. Micropropagation can be used for large-scale multiplication of essential oil producing plants thus avoiding an overexploitation of natural resources. This work aims to develop a reliable protocol for the in vitro propagation of Z. tenuior, and to compare the antioxidant activity between in vitro propagated and wild plants.The explants were sterilized and cultured on MS medium containing different concentrations of growth regulators naphthalene acetic acid (NAA) or indole-3-butyric acid (IBA) with 0.5 mg/L of kinetin (Kin) callus formation was 70.2% after 45 days of incubation in dark on medium supplemented with 1.5 mg/L of NAA. After one month of callus culture on medium supplemented with 2 mg/L BA the shoot number was 5.12 and for the multiplication stage. The shoot number was 4.21 and length was 6.17 cm on medium supplemented with 1 mg/L Kin + 0.1 mg/L NAA.DPPH• reagent was used to test the antioxidant activity. The aqueous and methanol extracts of in vitro plants which were treated with 1.5 and 1 mg/L of kin plus 0.1 mg/L of NAA showed a strong DPPH• scavenging activity where IC50 was 0.307 and 0.369 mg/ml, respectively, while the IC50 of aqueous and methanol extracts of wild plants was 0.516 and 9.229 mg/ml, respectively. Our results suggested that plant growth regulators and in vitro culture conditions increased the antioxidant activity.  相似文献   
28.
Salt tolerance ofEchinochloa crusgalli was studied using gravel culture with root medium electrical conductivity between 3 to 25 dS m-1. Salinity depressed germination and shoot yield. A 50 % reduction in shoot yield occurred at 15.9 dS m-1. The plant was able to maintain its tissue water content and K concentration in the tissue water while Na, Ca and Cl increased and Mg decreased with increasing root zone salinity.  相似文献   
29.
Neurodegeneration is an early event in the diabetic retina which may lead to diabetic retinopathy. One of the potential pathways in damaging retinal neurons is the activation of renin angiotensin system including angiotensin II type 1 receptor (AT1R) in the diabetic retina. The purpose of this study was to determine the effect of telmisartan, an AT1R blocker on retinal level of brain derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF) and tyrosine hydroxylase (TH), glutathione (GSH) and caspase activity in the diabetic rats. The dysregulated levels of these factors are known to cause neurodegeneration in diabetic retina. Three weeks streptozotocin induced diabetic rats were orally treated or untreated with telmisartan (10 mg/kg/day). After 4 weeks of treatments, the levels of BDNF and GSH were found to be increased systemically in the sera as well as in the retina of diabetic rats compared to untreated rats as measured by enzyme-linked immunosorbent assay and biochemical techniques (p < 0.05). The caspase-3 activity in the telmisartan treated diabetic retina was decreased compared to untreated diabetic rats (p < 0.05). Western blotting experiments showed the expression levels of BDNF, CNTF and TH were increased compared to untreated diabetic rats (p < 0.05). Thus, our findings show a beneficial effect of AT1R blocker telmisartan in efficiently increasing neurotrophic support, endogenous antioxidant GSH content, and decreasing signs of apoptosis in diabetic retina.  相似文献   
30.
A 6‐month long study was conducted to improve the nutritional quality of the cultured sobaity bream, Sparidentex hasta by feeding them finisher feeds containing high docosahexaenoic acid (DHA) at the last two months of the grow‐out stage so that the muscle DHA level be increased at par to the wild. A grow‐out feed used from the beginning until the end of the trial was considered as the control (Diet 1). Experimental diets 2 and 3 were formulated to contain 9.0% DHA (e.g. 1.68 g DHA/100 g feed) and 10.5% DHA (2.20 g DHA/100 g feed), by incorporating high DHA tuna oil into a sea bream grow‐out diet. For comparison, a commercial finisher feed (Diet 4) from Skretting, Italy was also used. The results of this study demonstrated that fish fed DHA enriched finisher diets resulted in significantly (p < .05) better growth, feed utilization and higher muscle eicosapentaenoic acid (EPA) and DHA content compared to those fed grow‐out diet. The muscle DHA and EPA of fish fed finisher diets were also higher than those of the whole year average DHA and EPA content of wild sobaity. An organoleptic evaluation showed no significant (p > .05) differences between sensory attributes of muscle from cultured and wild sea bream. The results of the study demonstrated that feeding finisher feed enriched with DHA at the later part of the grow‐out operation, the n‐3 PUFA levels of cultured sobaity can cost‐effectively be increased at par to the wild.  相似文献   
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