852 resultados para Salt-tolerant variant


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The objective of this study was to evaluate the association of PPARG coactivator1 alpha (PPARGC1A), peroxisome proliferator activated receptor gamma (PPARG), and uncoupling protein1 (UCP1) gene polymorphisms with the metabolic syndrome (MS) in an Asian Indian population. Nine common polymorphisms were genotyped via polymerase chain reaction restriction fragment length polymorphism and direct sequencing in 950 normal glucose-tolerant subjects and 550 type 2 diabetic subjects, chosen randomly from the Chennai Urban Rural Epidemiological Study, an ongoing population based study in Southern India. Among the 9 polymorphisms examined, only the Thr394Thr variant of the PPARGC1A gene was significantly associated with diabetes and obesity. The genotype frequency of GA of Thr394Thr variant was 16% (138/887) in the nonMS group and 22% (136/613) in the MS group, and this genotype frequency was significantly higher with MS both in males (p = 0.01) and females (p = 0.05), compared to the without-MS group. Logistic regression analysis revealed that the odds ratio for MS for the susceptible genotype GA of Thr394Thr was 1.411 [95% CI: 1.03-1.84, p = 0.012]. In the multiple logistic regression analysis, however, there was no association of this polymorphism as an independent factor with MS. Hence, the study shows that the polymorphisms in the PPARGC1A, PPARG and UCP1 genes are not associated with MS in Asian Indians.

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There is strong evidence for the link between high dietary sodium and increased risk of cardiovascular disease which drives the need to reduce salt content in foods. In this study, herb and spice blends were used to enhance consumer acceptability of a low salt tomato soup (0.26% w/w). Subjects (n=148) scored their liking of tomato soup samples over five consecutive days. The first and last days were pre-and post-exposure visits where all participants rated three tomato soup samples; standard, low salt and low salt with added herbs and spices. The middle 3 days were the repeated exposure phase where participants were divided into three balanced groups; consuming the standard soup, the low salt soup, or the low salt soup with added herbs and spices. Reducing salt in the tomato soup led to a significant decline in consumer acceptability, and incorporating herbs and spices did not lead to an immediate enhancement in liking. However, inclusion of herbs and spices enhanced the perception of the salty taste of the low salt soup to the same level as the standard. Repeated exposure to the herbs and spice-modified soup led to a significant increase in the overall liking and liking of flavour, texture and aftertaste of the soup, whereas no changes in liking were observed for the standard and low salt tomato soups over repeated exposure. Moreover, a positive trend in increasing the post-exposure liking of the herbs and spices soup was observed. The findings suggest that the use of herbs and spices is a useful approach to reduce salt content in foods; however, herbs and spices should be chosen carefully to complement the food as large contrasts in flavour can polarise consumer liking.

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Simulated intestinal fluids (SIFs) used to assay the solubility of orally administered drugs are typically based on a single bile salt; sodium taurocholate (STC). The aim of this study was to develop mimetic intestinal fluids with a closer similarity to physiological fluids than those reported to date by developing a mixed bile salt (MBS) system (STC, sodium glycodeoxycholate, sodium deoxycholate; 60:39:1) with different concentrations of lecithin, the preponderant intestinal phospholipid. Hydrocortisone and progesterone were used as model drugs to evaluate systematically the influence of SIF composition on solubility. Increasing total bile salt concentration from 0 to 30 mM increased hydrocortisone and progesterone solubility by 2- and ∼25-fold, respectively. Accordingly, higher solubilities were measured in the fed-state compared to the fasted-state SIFs. Progesterone showed the greatest increases in solubility in STC and MBS systems (2-7-fold) compared to hydrocortisone (no significant change; P>0.05) as lecithin concentration was increased. Overall, MBS systems gave similar solubility profiles to STC. In conclusion, the addenda of MBS and lecithin were found to be secondary to the influence of BS concentration. These data provide a foundation for the design of more bio-similar media for pivotal decision-guiding assays in drug development and quality control settings.

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In situ generation of HCl or HBr in alcohol leads to O-protonation of the amide group of carbamazepine. Six salt phases have been produced using this method and their crystal structures determined by single crystal diffraction. A new polymorph of carbamazepine hydrochloride is described as are two polymorphs of carbamazepine hydrobromide. All are protonated at the amide O atom to give RC(OH)NH2 cations. Prolonged exposure to air results in addition of water to the solid salt forms. Such hydration of carbamazepine hydrobromide simply gives a monohydrated phase, but similar treatment of the equivalent hydrochloride results in partial loss of HCl and the transfer of the remaining proton from the amide group to water to give [carbamazepine][H3O]0.5[Cl]0.5·H2O. A similar hydronium chloride species is the only product isolated after reaction of the carbamazepine analogue cytenamide with HCl generated in methanol.

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Myostatin plays a fundamental role in regulating the size of skeletal muscles. To date, only a single myostatin gene and no splice variants have been identified in mammals. Here we describe the splicing of a cryptic intron that removes the coding sequence for the receptor binding moiety of sheep myostatin. The deduced polypeptide sequence of the myostatin splice variant (MSV) contains a 256 amino acid N-terminal domain, which is common to myostatin, and a unique C-terminus of 65 amino acids. Western immunoblotting demonstrated that MSV mRNA is translated into protein, which is present in skeletal muscles. To determine the biological role of MSV, we developed an MSV over-expressing C2C12 myoblast line and showed that it proliferated faster than that of the control line in association with an increased abundance of the CDK2/Cyclin E complex in the nucleus. Recombinant protein made for the novel C-terminus of MSV also stimulated myoblast proliferation and bound to myostatin with high affinity as determined by surface plasmon resonance assay. Therefore, we postulated that MSV functions as a binding protein and antagonist of myostatin. Consistent with our postulate, myostatin protein was co-immunoprecipitated from skeletal muscle extracts with an MSV-specific antibody. MSV over-expression in C2C12 myoblasts blocked myostatin-induced Smad2/3-dependent signaling, thereby confirming that MSV antagonizes the canonical myostatin pathway. Furthermore, MSV over expression increased the abundance of MyoD, Myogenin and MRF4 proteins (P,0.05), which indicates that MSV stimulates myogenesis through the induction of myogenic regulatory factors. To help elucidate a possible role in vivo, we observed that MSV protein was more abundant during early post-natal muscle development, while myostatin remained unchanged, which suggests that MSV may promote the growth of skeletal muscles. We conclude that MSV represents a unique example of intra-genic regulation in which a splice variant directly antagonizes the biological activity of the canonical gene product.

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Background Autism Spectrum Conditions (ASC) are neurodevelopmental conditions characterized by difficulties in communication and social interaction, alongside unusually repetitive behaviours and narrow interests. Asperger Syndrome (AS) is one subgroup of ASC and differs from classic autism in that in AS there is no language or general cognitive delay. Genetic, epigenetic and environmental factors are implicated in ASC and genes involved in neural connectivity and neurodevelopment are good candidates for studying the susceptibility to ASC. The aryl-hydrocarbon receptor nuclear translocator 2 (ARNT2) gene encodes a transcription factor involved in neurodevelopmental processes, neuronal connectivity and cellular responses to hypoxia. A mutation in this gene has been identified in individuals with ASC and single nucleotide polymorphisms (SNPs) have been nominally associated with AS and autistic traits in previous studies. Methods In this study, we tested 34 SNPs in ARNT2 for association with AS in 118 cases and 412 controls of Caucasian origin. P values were adjusted for multiple comparisons, and linkage disequilibrium (LD) among the SNPs analysed was calculated in our sample. Finally, SNP annotation allowed functional and structural analyses of the genetic variants in ARNT2. We tested the replicability of our result using the genome-wide association studies (GWAS) database of the Psychiatric Genomics Consortium (PGC). Results We report statistically significant association of rs17225178 with AS. This SNP modifies transcription factor binding sites and regions that regulate the chromatin state in neural cell lines. It is also included in a LD block in our sample, alongside other genetic variants that alter chromatin regulatory regions in neural cells. Conclusions These findings demonstrate that rs17225178 in the ARNT2 gene is associated with AS and support previous studies that pointed out an involvement of this gene in the predisposition to ASC.

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In cooperative communication networks, owing to the nodes' arbitrary geographical locations and individual oscillators, the system is fundamentally asynchronous. Such a timing mismatch may cause rank deficiency of the conventional space-time codes and, thus, performance degradation. One efficient way to overcome such an issue is the delay-tolerant space-time codes (DT-STCs). The existing DT-STCs are designed assuming that the transmitter has no knowledge about the channels. In this paper, we show how the performance of DT-STCs can be improved by utilizing some feedback information. A general framework for designing DT-STC with limited feedback is first proposed, allowing for flexible system parameters such as the number of transmit/receive antennas, modulated symbols, and the length of codewords. Then, a new design method is proposed by combining Lloyd's algorithm and the stochastic gradient-descent algorithm to obtain optimal codebook of STCs, particularly for systems with linear minimum-mean-square-error receiver. Finally, simulation results confirm the performance of the newly designed DT-STCs with limited feedback.

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We investigated the potential of soil moisture and nutrient amendments to enhance the biodegradation of oil in the soils from an ecologically unique semi-arid island. This was achieved using a series of controlled laboratory incubations where moisture or nutrient levels were experimentally manipulated. Respired CO2 increased sharply with moisture amendment reflecting the severe moisture limitation of these porous and semi-arid soils. The greatest levels of CO2 respiration were generally obtained with a soil pore water saturation of 50–70%. Biodegradation in these nutrient poor soils was also promoted by the moderate addition of a nitrogen fertiliser. Increased biodegradation was greater at the lowest amendment rate (100 mg N kg−1 soil) than the higher levels (500 or 1,000 mg N kg−1 soil), suggesting the higher application rates may introduce N toxicity. Addition of phosphorous alone had little effect, but a combined 500 mg N and 200 mg P kg−1 soil amendment led to a synergistic increase in CO2 respiration (3.0×), suggesting P can limit the biodegradation of hydrocarbons following exogenous N amendment.

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Treatment of emerging RNA viruses is hampered by the high mutation and replication rates that enable these viruses to operate as a quasispecies. Declining honey bee populations have been attributed to the ectoparasitic mite Varroa destructor and its affiliation with Deformed Wing Virus (DWV). In the current study we use next-generation sequencing to investigate the DWV quasispecies in an apiary known to suffer from overwintering colony losses. We show that the DWV species complex is made up of three master variants. Our results indicate that a new DWV Type C variant is distinct from the previously described types A and B, but together they form a distinct clade compared with other members of the Iflaviridae. The molecular clock estimation predicts that Type C diverged from the other variants ~319 years ago. The discovery of a new master variant of DWV has important implications for the positive identification of the true pathogen within global honey bee populations.

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The products of reactions of the pharmaceutical amide carbamazepine (CBZ) with strong acids under aqueous conditions were investigated by both powder and single crystal X-ray diffraction. Despite previous claims to the contrary, it was found that salt forms with CBZ protonated at the amide O atom could be isolated from reactions with both HCl and HBr. These forms include the newly identified hydrate phase [CBZ(H)][Cl]·H O. Reactions with other mineral acids (HI and HBF ) gave ionic cocrystalline (ICC) forms (CBZ· [acridinium][I ]·2.5I and CBZ·[H O ] [BF ] ·H O) as well as the salt form CBZ·[CBZ(H)][BF ]·0.5H O. Reaction 2 4 3 2 5 2 0.25 4 0.25 2 4 2 of CBZ with a series of sulfonic acids also gave salt forms, namely, [CBZ(H)][O SC H ], [CBZ(H)][O SC H (OH)]· 3 6 5 3 6 4 0.5H O, [CBZ(H)] [O SCH CH SO ], and [CBZ(H)][O SC H (OH) (COOH)]·H O. CBZ and protonated CBZ(H) 2 2 3 2 2 3 3 6 3 2 moieties can be differentiated in the solid state both by changes to molecular geometry and by differing packing preferences

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Future extreme-scale high-performance computing systems will be required to work under frequent component failures. The MPI Forum's User Level Failure Mitigation proposal has introduced an operation, MPI_Comm_shrink, to synchronize the alive processes on the list of failed processes, so that applications can continue to execute even in the presence of failures by adopting algorithm-based fault tolerance techniques. This MPI_Comm_shrink operation requires a fault tolerant failure detection and consensus algorithm. This paper presents and compares two novel failure detection and consensus algorithms. The proposed algorithms are based on Gossip protocols and are inherently fault-tolerant and scalable. The proposed algorithms were implemented and tested using the Extreme-scale Simulator. The results show that in both algorithms the number of Gossip cycles to achieve global consensus scales logarithmically with system size. The second algorithm also shows better scalability in terms of memory and network bandwidth usage and a perfect synchronization in achieving global consensus.

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Background: ABCA1 plays an important role in HDL metabolism. Single nucleotide polymorphisms (SNPs) in ABCA1 gene were associated with variation in plasina HDL-c. Methods: The effect of the ABCA1 SNPs C-14T, R219K and of a novel variant C-105T on serum lipids was investigated in 367 unrelated Brazilian individuals (224 hypercholesterolemic and 143 normolipidemic). The relation between ABCA1 SNPs and the lipid-lowering response to atorvastatin (10 mg/day/4 weeks) was also evaluated in 141 hypercholesterolemic (HC) individuals. The polymorphisms were detected by PCRR_FLP and confirmed by DNA sequencing. Results: Linkage disequilibrium was found between the SNPs C-105T and C-14T in the HC group. HC individuals carrying - 105CT/TT genotypes had higher serum HDL-c and lower triglyceride and VLDL-c concentrations as well as lower TG/HDL-c ratio compared to the -105CC carriers (p<0.05). The R219K SNP was associated with reduced serum triglyceride, VLDL-c and TG/HDL-c ratio in the HC group (p<0.05), and with an increased serum apoAI in NL individuals. The effects of ABCA1 SNPs on basal serum lipids of HC individuals were not modified by atorvastatin treatment. Conclusions: The ABCA1 SNPs R219K and C-105T were associated with a less atherogenic lipid profile but not with the lowering-cholesterol response to atorvastatin in a Brazilian population. (C) 2007 Elsevier B.V. All rights reserved.

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We evaluated the development of arterial hypertension, cardiac function, and collagen deposition, as well as the level of components of the renin-angiotensin system in the heart of transgenic rats that overexpress an angiotensin (Ang)-(1-7)-producing fusion protein, TGR(A1-7)3292 (TG), which induces a lifetime increase in circulating levels of this peptide. After 30 days of the induction of the deoxycorticosterone acetate (DOCA)-salt hypertension model, DOCA-TG rats were hypertensive but presented a lower systolic arterial pressure in comparison with DOCA-Sprague-Dawley (SD) rats. In contrast to DOCA-SD rats that presented left ventricle (LV) hypertrophy and diastolic dysfunction, DOCA-TG rats did not develop cardiac hypertrophy or changes in ventricular function. In addition, DOCA-TG rats showed attenuation in mRNA expression for collagen type I and III compared with the increased levels of DOCA-SD rats. Ang II plasma and LV levels were reduced in SD and TG hypertensive rats in comparison with normotensive animals. DOCA-TG rats presented a reduction in plasma Ang-(1-7) levels; however, there was a great increase in Ang-(1-7) (approximate to 3-fold) accompanied by a decrease in mRNA expression of both angiotensin-converting enzyme and angiotensin-converting enzyme 2 in the LV. The mRNA expression of Mas and Ang II type 1 receptors in the LV was not significantly changed in DOCA-SD or DOCA-TG rats. This study showed that TG rats with increased circulating levels of Ang-(1-7) are protected against cardiac dysfunction and fibrosis and also present an attenuated increase in blood pressure after DOCA-salt hypertension. In addition, DOCA-TG rats showed an important local increase in Ang-(1-7) levels in the LV, which might have contributed to the attenuation of cardiac dysfunction and prefibrotic lesions. (Hypertension. 2010;55:889-896.)

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Cambial variants represent a form of secondary growth that creates great stem anatomical diversity in lianas. Despite the importance of cambial variants, nothing is known about the developmental mechanisms that may have led to the current diversity seen in these stems. Here, a thorough anatomical analysis of all genera along the phylogeny of Bignonieae (Bignoniaceae) was carried out in order to detect when in their ontogeny and phylogeny there were shifts leading to different stem anatomical patterns. We found that all species depart from a common developmental basis, with a continuous, regularly growing cambium. Initial development is then followed by the modification of four equidistant portions of the cambium that reduce the production of xylem and increase the production of phloem, the former with much larger sieve tubes and an extended lifespan. In most species, the formerly continuous cambium becomes disjunct, with cambial portions within phloem wedges and cambial portions between them. Other anatomical modifications such as the formation of multiples of four phloem wedges, multiple-dissected phloem wedges, and included phloem wedges take place thereafter. The fact that each novel trait raised on the ontogenetic trajectory appeared in subsequently more recent ancestors on the phylogeny suggests a recapitulatory history. This recapitulation is, however, caused by the terminal addition of evolutionary novelties rather than a truly heterochronic process. Truly heterochronic processes were only found in shrubby species, which resemble juveniles of their ancestors, as a result of a decelerated phloem formation by the variant cambia. In addition, the modular evolution of phloem and xylem in Bignonieae seems to indicate that stem anatomical modifications in this group occurred at the level of cambial initials.