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81.
17β-Hydroxysteroid dehydrogenase type 1 (17β-HSD1) catalyzes the formation of the potent proliferation-stimulating hormone estradiol, and it is thus involved in the development of hormone-dependent breast cancer. Due to its high substrate specificity and the known relationships between its overexpression and disease incidence, 17β-HSD1 is considered an attractive target for drug development. Here, we have used structure-based virtual high-throughput screening to successfully identify potent nonsteroidal 17β-HSD1 inhibitors. Computational screening of a drug-like database containing 13 million compounds identified hits with a 2-benzylidenebenzofuran-3(2H)-one scaffold that we show to be highly potent 17β-HSD1 inhibitors. The most potent in the series, compound 1, showed an IC(50) of 45nM in our 17β-HSD1 inhibition assay, and also showed good selectivity for 17β-HSD1 over 17β-HSD2.  相似文献   
82.
Evaluation of a hydrogel-fiber composite for ACL tissue engineering   总被引:1,自引:0,他引:1  
The anterior cruciate ligament (ACL) is necessary for normal knee stability and movement. Unfortunately the ACL is also the most frequently injured ligament of the knee with severe disruptions requiring surgical intervention. In response to this, tissue engineering has emerged as an option for ACL replacement and repair. In this study we present a novel hydrogel-fibrous scaffold as a potential option for ACL replacement. The scaffold was composed of PLLA fibers, in a previously evaluated braid-twist structure, combined with a polyethylene glycol diacrylate (PEGDA) hydrogel to improve viscoelastic properties. Both hydrogel concentration (10%, 15%, and 20%) and amount of hydrogel (soaking the fibrous scaffold in hydrogel solution or encasing the scaffold in a block of hydrogel) were evaluated. It was found that the braid-twist scaffold had a greater porosity and larger number of pores above 100 μm than braided scaffolds with the same braiding angle. After testing for their effects on swelling, fiber degradation, and protein release, as well as viscoelastic and tensile testing (when combined with fibrous scaffolds), it was found that the composite scaffold soaked in 10% hydrogel had the best chemical release and mechanical properties. The optimized structure behaved similarly to natural ligament in tension with the addition of the hydrogel decreasing the ultimate tensile stress (UTS), but the UTS was still comparable to natural ACL. In addition, cellular studies showed that the hydrogel-PLLA fiber composite supported fibroblast growth.  相似文献   
83.
Using ultrasound in evaluation of infant's hip development can reduce surgical procedures, hospitalization and late presentation of developmental dysplasia of the hip (DDH). The increasing incidence of DDH after ultrasound examination is observed and published by many authors. In a prospective study, radiograph of every single ultrasonographic positive hip in infants older than three months, was taken and analyzed in order to see whether it affects infants splintage rate in treating DDH. In a period of 30 months, clinical and simple static ultrasonographic examinations according to Graf were performed on 1430 consecutive infant hips in patients aged between 4 and 6 months. Sonographic positive hips were radiographed and acetabular index (AI) values on simple AP radiographs were analyzed. The sonographic DDH incidence was 51.75 per 1000 hips (51.75 per thousand). After X-ray examination of all 74 ultrasonographic positive hips, only 44 remained abnormal and required treatment indicating a true DDH incidence of 30.77 per 1000 hips (30.77 per thousand). The difference in incidence per ultrasonographic and X-ray positive hips is statistically significant p < 0.01 (t = 5,536). The rational approach in detection of DDH in a child more than 3 months old is to do radiographic assessment of every sonographic positive hip.  相似文献   
84.
85.

Background

The genetic code is redundant, meaning that most amino acids can be encoded by more than one codon. Highly expressed genes tend to use optimal codons to increase the accuracy and speed of translation. Thus, codon usage biases provide a signature of the relative expression levels of genes, which can, uniquely, be quantified across the domains of life.

Results

Here we describe a general statistical framework to exploit this phenomenon and to systematically associate genes with environments and phenotypic traits through changes in codon adaptation. By inferring evolutionary signatures of translation efficiency in 911 bacterial and archaeal genomes while controlling for confounding effects of phylogeny and inter-correlated phenotypes, we linked 187 gene families to 24 diverse phenotypic traits. A series of experiments in Escherichia coli revealed that 13 of 15, 19 of 23, and 3 of 6 gene families with changes in codon adaptation in aerotolerant, thermophilic, or halophilic microbes. Respectively, confer specific resistance to, respectively, hydrogen peroxide, heat, and high salinity. Further, we demonstrate experimentally that changes in codon optimality alone are sufficient to enhance stress resistance. Finally, we present evidence that multiple genes with altered codon optimality in aerobes confer oxidative stress resistance by controlling the levels of iron and NAD(P)H.

Conclusions

Taken together, these results provide experimental evidence for a widespread connection between changes in translation efficiency and phenotypic adaptation. As the number of sequenced genomes increases, this novel genomic context method for linking genes to phenotypes based on sequence alone will become increasingly useful.  相似文献   
86.
Objective of this paper is to estimate interim risk factors (INTF) proportions and changes within 5-years of groups with at least one risk health behavior (BEHF) in CroHort population. Results show that CroHort 2008 group has higher proportions of excess abdominal fat and overweight. Men older than 65 without any BEHF have smaller proportions of INTF in 2008 than in 2003. Proportion of people with high blood pressure is smaller in 2008 for all groups except for young women who show increase. Analysis of middle age group shows significant increase in all INTF in women smokers while men smokers have the highest increase in abdominal fat. Physical inactivity in women is associated with increase of all INTF, while men have decrease in overweight INTF. Alcohol intake has protective effect on middle aged men, except for increase in waist circumference. Women show constant increase in all INTF with heavy alcohol intake.  相似文献   
87.
The aims of this paper are to investigate the change in prevalence of psychological distress (PD), to investigate the cumulative incidence of the psychological distress and to indicate are there any differences between genders and various age groups in Croatian adult population. Psychological distress status was measured by the five-item Mental Health Scale (MHI-5) of the Short Form questionnaire (SF-36). Psychological distress was present in 28.5% (95% CI 25.7%-31.2%) of men and 32.1% (95% CI 30.1%-34.0%) of women in 2003. In 2008 PD was present in 33.0% (95% CI 30.1%-35.9%) of men and 34.1% (95% CI 32.1%-36.0%) of women. The highest incidence of PD, both for men and women, was in the oldest age group (> 65 years). Results of this study demonstrating the fact that every third adult men and woman in Croatia are in psychological distress, the fact that there is an increase in PD prevalence for men and women should be taken into account in the future mental health policy planning.  相似文献   
88.
Rural areas, where 47.6% of the Croatian population lives are not generally the focus of research; yet there are challenges which affect the rural population that often go unreported. These communities often exhibit disadvantages in many areas of health. The aim of this study is to examine the specific health needs and related determinants of rural populations influenced by transition that were affected by the consequences of war. The focus of the research is rural lifestyle, behaviour and cardiovascular risk factors in three villages of Sisacko-moslavacka County. Results show that participants generally understand that their own lifestyles influence their health, but they often neglect to change their behaviour to improve their health. This can be explained through complex socio-economic conditions and traditional values of their heritage. These results suggest a need for further research on health status, attitude, and behaviour of Croatia's rural population. Specific public health intervention and services for rural populations must be promoted.  相似文献   
89.
T Huotari  H Korpelainen 《Gene》2012,508(1):96-105
Elodea canadensis is an aquatic angiosperm native to North America. It has attracted great attention due to its invasive nature when transported to new areas in its non-native range. We have determined the complete nucleotide sequence of the chloroplast (cp) genome of Elodea. Taxonomically Elodea is a basal monocot, and only few monocot cp genomes representing early lineages of monocots have been sequenced so far. The genome is a circular double-stranded DNA molecule 156,700bp in length, and has a typical structure with large (LSC 86,194bp) and small (SSC 17,810bp) single-copy regions separated by a pair of inverted repeats (IRs 26,348bp each). The Elodea cp genome contains 113 unique genes and 16 duplicated genes in the IR regions. A comparative analysis showed that the gene order and organization of the Elodea cp genome is almost identical to that of Amborella trichopoda, a basal angiosperm. The structure of IRs in Elodea is unique among monocot species with the whole cp genome sequenced. In Elodea and another monocot Lemna minor the borders between IRs and LSC are located upstream of rps19 gene and downstream of trnH-GUG gene, while in most monocots, IR has extended to include both trnH and rps19 genes. A phylogenetic analysis conducted using Bayesian method, based on the DNA sequences of 81 chloroplast genes from 17 monocot taxa provided support for the placement of Elodea together with Lemna as a basal monocot and the next diverging lineage of monocots after Acorales. In comparison with other monocots, the Elodea cp genome has gone through only few rearrangements or gene losses. IR of Elodea has a unique structure among the monocot species studied so far as its structure is similar to that of a basal angiosperm Amborella. This result together with phylogenetic analyses supports the placement of Elodea as a basal monocot to the next diverging lineage of monocots after Acorales. So far, only few cp genomes representing early lineages of monocots have been sequenced and, therefore, this study provides valuable information about the course of evolution in divergence of monocot lineages.  相似文献   
90.

Background

Adequate foetal growth is primarily determined by nutrient availability, which is dependent on placental nutrient transport and foetal metabolism. We have used 1H nuclear magnetic resonance (NMR) spectroscopy to probe the metabolic adaptations associated with premature birth.

Methodology

The metabolic profile in 1H NMR spectra of plasma taken immediately after birth from umbilical vein, umbilical artery and maternal blood were recorded for mothers delivering very-low-birth-weight (VLBW) or normo-ponderal full-term (FT) neonates.

Principal Findings

Clear distinctions between maternal and cord plasma of all samples were observed by principal component analysis (PCA). Levels of amino acids, glucose, and albumin-lysyl in cord plasma exceeded those in maternal plasma, whereas lipoproteins (notably low-density lipoprotein (LDL) and very low-density lipoprotein (VLDL) and lipid levels were lower in cord plasma from both VLBW and FT neonates. The metabolic signature of mothers delivering VLBW infants included decreased levels of acetate and increased levels of lipids, pyruvate, glutamine, valine and threonine. Decreased levels of lipoproteins glucose, pyruvate and albumin-lysyl and increased levels of glutamine were characteristic of cord blood (both arterial and venous) from VLBW infants, along with a decrease in levels of several amino acids in arterial cord blood.

Conclusion

These results show that, because of its characteristics and simple non-invasive mode of collection, cord plasma is particularly suited for metabolomic analysis even in VLBW infants and provides new insights into the materno-foetal nutrient exchange in preterm infants.  相似文献   
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