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91.
92.
Journal of Plant Growth Regulation - Salt stress is a main factor limiting the production and productivity of wheat in arid and semi-arid zones. The objectives of this study were to compare the...  相似文献   
93.
Data included 393,097 calving ease, 129,520 gestation length, and 412,484 birth weight records on 412,484 Gelbvieh cattle. Additionally, pedigrees were available on 72,123 animals. Included in the models were effects of sex and age of dam, treated as fixed, as well as direct, maternal genetic and permanent environmental effects and effects of contemporary group (herd-year-season), treated as random. In all analyses, birth weight and gestation length were treated as continuous traits. Calving ease (CE) was treated either as a continuous trait in a mixed linear model (LM), or as a categorical trait in linear-threshold models (LTM). Solutions in TM obtained by empirical Bayes (TMEB) and Monte Carlo (TMMC) methodologies were compared with those by LM. Due to the computational cost, only 10,000 samples were obtained for TMMC. For calving ease, correlations between LM and TMEB were 0.86 and 0.78 for direct and maternal genetic effects, respectively. The same correlations but between TMEB and TMMC were 1.00 and 0.98, respectively. The correlations between LM and TMMC were 0.85 and 0.75, respectively. The correlations for the linear traits were above.97 between LM and TMEB but as low as 0.91 between LM and TMMC, suggesting insufficient convergence of TMMC. Computing time required was about 2 hrs, 5 hrs, and 6 days for LM, TMEB and TMMC, respectively, and memory requirements were 169, 171, and 445 megabytes, respectively. Bayesian implementation of threshold model is simple, can be extended to multiple categorical traits, and allows easy calculation of accuracies; however, computing time is prohibitively long for large models.  相似文献   
94.
Currently, there are no differentiation strategies for human embryonic stem cells (hESCs) that efficiently produce one specific cell type, possibly because of lack of understanding of the genes that control signaling events prior to overt differentiation. sed HepG2 cell conditioned medium (MEDII), which induces early differentiation in mouse ES cells while retaining pluripotent markers, to query gene expression in hESCs. Treatment of adherent hESCs with 50% MEDII medium effected differentiation to a cell type with gene expression similar to primitive streak stage cells of mouse embryos. MEDII treatment up-regulates TDGF1 (Cripto), a gene essential for anterior-posterior axis and mesoderm formation in mouse embryos and a key component of the TGFB1/NODAL signaling pathway. LEFTYA, an antagonist of NODAL/TDGF1 signaling expressed in anterior visceral endoderm, is down-regulated with MEDII treatment, as is FST, an inhibitor of mesoderm induction via the related INHBE1 pathway. In summary, the TGFB1/NODAL pathway is important for primitive-streak and mesoderm formation and in using MEDII, we present a means for generating an in vitro cell population that maintains pluripotent gene expression (POU5F1, NANOG) and SSEA-4 markers while regulating genes in the TGFB1/NODAL pathway, which may lead to more uniform formation of mesoderm in vitro.  相似文献   
95.
This paper describes the trends in tobacco sales and smoking prevalence in the Tunisian population, estimates the consequences of smoking on mortality of this population, and discusses anti-tobacco actions: educational actions, legislative measures and price increases. Sales Data were collected from the Tunisia tobacco company. Smoking prevalence data from surveys, conducted by several institutes, and numbers of deaths by causes have been estimated from WHO for the year 1998. Tobacco sales increased from 4.96 g per adult per day in 1981, to 6.3 g, in 1993, then decreased widely. The proportion of smokers was 30% in 1996. 55% among men versus 5.6% among women. Among 17 to 24 years old young adults, the proportion of smokers was 29.2% in 1994 (50% among men versus 3.9%, among women). Mortality attributable to tobacco in Tunisia has been estimated to 6430 deaths in 1997 (5580 among men versus 850 among women). These deaths represent 22% of the total male deaths and 4% of the female ones. Anti-tobacco measures have been reinforced by the enactment of anti-tobacco law. Proportion of young smokers remaining elevated, it is expected that consequences of the tobacco addiction in Tunisia, in term of mortality, will be even heavier in the next two decades, if efficient anti-tobacco actions are not implemented.  相似文献   
96.

Introduction

Two replicate randomized, placebo-controlled six-month trials (RCTs) and an open-label treatment extension (OLE) comprised the pegloticase development program in patients with gout refractory to conventional therapy. In the RCTs, approximately 40% of patients treated with the approved dose saw complete response (CR) of at least one tophus. Here we describe the temporal course of tophus resolution, total tophus burden in patients with multiple tophi, tophus size at baseline, and the relationship between tophus response and urate-lowering efficacy.

Methods

Baseline subcutaneous tophi were analyzed quantitatively using computer-assisted digital images in patients receiving pegloticase (8 mg biweekly or monthly) or placebo in the RCTs, and pegloticase in the OLE. Tophus response, a secondary endpoint in the trials, was evaluated two ways. Overall tophus CR was the proportion of patients achieving a best response of CR (without any new/enlarging tophi) and target tophus complete response (TT-CR) was the proportion of all tophi with CR.

Results

Among 212 patients randomized in the RCTs, 155 (73%) had ≥1 tophus and 547 visible tophi were recorded at baseline. Overall tophus CR was recorded in 45% of patients in the biweekly group (P = 0.002 versus placebo), 26% in the monthly group, and 8% in the placebo group after six months of RCT therapy. TT-CR rates at six months were 28%, 19%, and 2% of tophi, respectively. Patients meeting the primary endpoint of sustained urate-lowering response to therapy (responders) were more likely than nonresponders to have an overall tophus CR at six months (54% vs 20%, respectively and 8% with placebo).Both overall tophus CR and TT-CRs increased with treatment duration in the OLE, reaching 70% (39/56) of patients and 55% (132/238) of target tophi after one year of treatment in patients receiving pegloticase during both the RCTs and OLE. At that time point, more tophi had resolved in responders (102/145 or 70% of tophi) than nonresponders (30/93; 32%).

Conclusions

Pegloticase reduced tophus burden in patients with refractory tophaceous gout, especially those achieving sustained urate-lowering. Complete resolution of tophi occurred in some patients by 13 weeks and in others with longer-term therapy.

Trial registrations

NCT00325195, NCT01356498  相似文献   
97.
Artemia has a remarkable genetic variability that can be expressed in various phenotypic characteristics, such as morphometry, growth rate, reproductive isolation or molecular composition. This study presents reproduction characteristics, survival rate and sex-ratio of four Artemia salina populations from Tunisia cultured under standard conditions. Results show that both low (17.8% and 30.6% in Megrine saltwork and Sabkhet Sijoumi, respectively) and high (83.9% for Sahline saltwork) values were recorded for the percentage of total oviparous offspring. The offspring per brood varied from 70.3?±?41.9 (Megrine saltwork) to 73.6?±?51.4 (Sabkhet El Adhibet). Broods per female varied between 3.1?±?0.9 (Sahline saltwork) and 4.5?±?1.2 (Megrine saltwork), and time between broods ranged from 5.7?±?1.1 to 6.5?±?2.2 days for Megrine and Sahline, respectively. Statistical analysis (one-way analysis of variance, Tukey's HSD test, p?<?0.05) revealed no significant differences between reproductive traits of the four studied populations except for mean of oviparous and oviviparous offspring per female (F?=?9.158, p?<?0.05), and brood per female (F?=?4.779, p?<?0.05). The survival rate of the four studied A. salina populations fluctuated between 31.4% and 64.5% for Megrine and Sahline saltwork, respectively. However, the sex-ratio showed that for Megrine saltwork and Sabkhet El Adhibet, males predominated with 1?:?0.90 and 1?:?0.97 (males?:?females), respectively. The comparison between our results and those reported of other Artemia populations showed that the offspring per brood of Tunisian Artemia are comparable to A. persimilis but different to A. salina from Abu Kammash (Libya) and A. urmiana (Urmia Lake, Iran), and that days between brood, are similar to A. salina from Abu Kammash, A. sinica and polyploid A. parthenogenetica, but different from A. persimilis and A. franciscana.  相似文献   
98.
Post ‘omic’ era has resulted in the development of many primary, secondary and derived databases. Many analytical and visualization bioinformatics tools have been developed to manage and analyze the data available through large sequencing projects. Availability of heterogeneous databases and tools make it difficult for researchers to access information from varied sources and run different bioinformatics tools to get desired analysis done. Building integrated bioinformatics platforms is one of the most challenging tasks that bioinformatics community is facing. Integration of various databases, tools and algorithm is a challenging problem to deal with. This article describes the bioinformatics analysis workflow management systems that are developed in the area of gene sequence analysis and phylogeny. This article will be useful for biotechnologists, molecular biologists, computer scientists and statisticians engaged in computational biology and bioinformatics research.  相似文献   
99.
Bottom trawl survey data are commonly used as a sampling technique to assess the spatial distribution of commercial species. However, this sampling technique does not always correctly detect a species even when it is present, and this can create significant limitations when fitting species distribution models. In this study, we aim to test the relevance of a mixed methodological approach that combines presence-only and presence-absence distribution models. We illustrate this approach using bottom trawl survey data to model the spatial distributions of 27 commercially targeted marine species. We use an environmentally- and geographically-weighted method to simulate pseudo-absence data. The species distributions are modelled using regression kriging, a technique that explicitly incorporates spatial dependence into predictions. Model outputs are then used to identify areas that met the conservation targets for the deployment of artificial anti-trawling reefs. To achieve this, we propose the use of a fuzzy logic framework that accounts for the uncertainty associated with different model predictions. For each species, the predictive accuracy of the model is classified as ‘high’. A better result is observed when a large number of occurrences are used to develop the model. The map resulting from the fuzzy overlay shows that three main areas have a high level of agreement with the conservation criteria. These results align with expert opinion, confirming the relevance of the proposed methodology in this study.  相似文献   
100.
Pathophysiological conditions that lead to the release of the prototypic damage-associated molecular pattern molecule high mobility group box 1 (HMGB1) also result in activation of poly(ADP-ribose) polymerase 1 (PARP1; now known as ADP-ribosyl transferase 1 [ARTD1]). Persistent activation of PARP1 promotes energy failure and cell death. The role of poly(ADP-ribosyl)ation in HMGB1 release has been explored previously; however, PARP1 is a versatile enzyme and performs several other functions including cross-talk with another nicotinamide adenine dinucleotide- (NAD+) dependent member of the Class III histone deacetylases (HDACs), sirtuin-1 (SIRT1). Previously, it has been shown that the hyperacetylation of HMGB1 is a seminal event prior to its secretion, a process that also is dependent on HDACs. Therefore, in this study, we seek to determine if PARP1 inhibition alters LPS-mediated HMGB1 hyperacetylation and subsequent secretion due to its effect on SIRT1. We demonstrate in an in vitro model that LPS treatment leads to hyperacetylated HMGB1 with concomitant reduction in nuclear HDAC activity. Treatment with PARP1 inhibitors mitigates the LPS-mediated reduction in nuclear HDAC activity and decreases HMGB1 acetylation. By utilizing an NAD+-based mechanism, PARP1 inhibition increases the activity of SIRT1. Consequently, there is an increased nuclear retention and decreased extracellular secretion of HMGB1. We also demonstrate that PARP1 physically interacts with SIRT1. Further confirmation of this data was obtained in a murine model of sepsis, that is, administration of PJ-34, a specific PARP1 inhibitor, led to decreased serum HMGB1 concentrations in mice subjected to cecal ligation and puncture (CLP) as compared with untreated mice. In conclusion, our study provides new insights in understanding the molecular mechanisms of HMGB1 secretion in sepsis.  相似文献   
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