Miracle-dz/UniFAR-FTUs huggingface dataset:
Effect of elevated temperatures and cooling regimes on normal strength concrete

The compressive strength of normal strength concrete at elevated temperatures up to 700∘C and the effect of cooling regimes were investigated and compared in this study. Thus, two different mixture groups with initial strengths of 20 and 35 MPa were produced by using river sand, normal aggregate and portland cement. Thirteen different temperature values were chosen from 50 to 700∘C. The specimens were heated for 3 h at each temperature. After heating, concretes were cooled to room temperature either in water rapidly or in laboratory conditions gradually. The residual strengths were determined by an axial compressive strength test. Strength and unit weight losses were compared with the initial values. Throughout this study, ASTM and Turkish Standards were used. It was observed that concrete properties deteriorated with the heat; however, a small increase in strength was observed from 50 to 100∘C. Strength loss was more significant on the specimens rapidly cooled in water. Both concrete mixtures lost a significant part of their initial strength when the temperature reached 700∘C. Copyright © 2008 John Wiley & Sons, Ltd.
Genetic and Molecular Insights Into the Role of PROX1 in Glucose Metabolism

Genome-wide association studies have shown that the rs340874 single nucleotide polymorphism (SNP) in PROX1 is a genetic susceptibility factor for type 2 diabetes. We conducted genetic and molecular studies to better understand the role of PROX1 in type 2 diabetes. We assessed the impact of the whole common genetic variability of PROX1 (80 SNPs) on type 2 diabetes–related biochemical traits in the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study (n = 1,155). Three SNPs (rs340838, rs340837, and rs340836) were significantly associated with fasting plasma insulin levels (P ≤ 0.00295). We evaluated the impact of nine PROX1 SNPs (the three insulin-associated SNPs plus six SNPs in strong linkage disequilibrium) on luciferase reporter gene expression. The insulin-lowering alleles of rs340874, rs340873, and rs340835 were associated with lower luciferase activity in MIN6 and HepG2 cells (except for rs340874, which was in HepG2 cells only). Electrophoretic mobility shift assays indicated that specific nuclear protein bindings occur at the three SNPs in HepG2 cells, with allele-binding differences for rs340874. We also showed that the knockdown of Prox1 expression by small interfering RNAs in INS-1E cells resulted in a 1.7-fold reduction in glucose-stimulated insulin secretion. All together, we propose that reduced expression of PROX1 by cis-regulatory variants results in altered β-cell insulin secretion and thereby confers susceptibility to type 2 diabetes.
RNA Polymerase II Binding Patterns Reveal Genomic Regions Involved in MicroRNA Gene Regulation

MicroRNAs are small non-coding RNAs involved in post-transcriptional regulation of gene expression. Due to the poor annotation of primary microRNA (pri-microRNA) transcripts, the precise location of promoter regions driving expression of many microRNA genes is enigmatic. This deficiency hinders our understanding of microRNA-mediated regulatory networks. In this study, we develop a computational approach to identify the promoter region and transcription start site (TSS) of pri-microRNAs actively transcribed using genome-wide RNA Polymerase II (RPol II) binding patterns derived from ChIP-seq data. Based upon the assumption that the distribution of RPol II binding patterns around the TSS of microRNA and protein coding genes are similar, we designed a statistical model to mimic RPol II binding patterns around the TSS of highly expressed, well-annotated promoter regions of protein coding genes. We used this model to systematically scan the regions upstream of all intergenic microRNAs for RPol II binding patterns similar to those of TSS from protein coding genes. We validated our findings by examining the conservation, CpG content, and activating histone marks in the identified promoter regions. We applied our model to assess changes in microRNA transcription in steroid hormone-treated breast cancer cells. The results demonstrate many microRNA genes have lost hormone-dependent regulation in tamoxifen-resistant breast cancer cells. MicroRNA promoter identification based upon RPol II binding patterns provides important temporal and spatial measurements regarding the initiation of transcription, and therefore allows comparison of transcription activities between different conditions, such as normal and disease states.
Characterization and substrate specificity of an endo-beta-1,4-D-glucanase I (Avicelase I) from an extracellular multienzyme complex of Bacillus circulans

An endo-1,4-beta-D-glucanase I (Avicelase I; EC 3.2.1.4) was purified to homogeneity from an extracellular celluloxylanosome of Bacillus circulans F-2. The purification in the presence of 6 M urea yielded homogeneous enzyme. The enzyme had a monomeric structure, its relative molecular mass being 75 kDa as determined by gel filtration and 82 kDa as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The pI was 5.4, and the N-terminal amino acid sequence was ASNIGGWVGGNESGFEFG. The optimal pH was 4.5, and the enzyme was stable at pH 4 to 10. The enzyme has a temperature optimum of 50 degrees C, it was stable at 55 degrees C for 46 h, and it retains approximately 20% of its activity after 30 min at 80 degrees C. It showed high-level activity towards carboxymethyl cellulose (CMC) as well as p-nitrophenyl-beta-D-cellobioside, 4-methylumbelliferyl cellobioside, xylan, Avicel, filter paper, and some cello-oligosaccharides. Km values for birch xylan, CMC, and Avicel were 4.8, 7.2, and 87.0 mg/ml, respectively, while Vmax values were 256, 210, and 8.6 mumol x min-1 x mg-1, respectively. Cellotetraose was preferentially cleaved into cellobiose (G2) plus G2, and cellopentaose was cleaved into G2 plus cellotriose (G3), while cellohexaose was cleaved into cellotetraose plus G2 and to a lesser extent G3 plus G3. G3 was not cleaved at all. G2 was the main product of Avicel hydrolysis. Xylotetraose (X4) and xylobiose (X2) were mainly produced by the enzyme hydrolysis of xylan. G2 inhibited the activity of carboxymethyl cellulase and Avicelase, whereas Mg2+ stimulated it. The enzyme was completely inactivated by Hg2+, and it was inhibited by a thiol-blocking reagent. Hydrolysis of CMC took place, with a rapid decrease in viscosity but a slow liberation of reducing sugars. On the basis of these results, it appeared that the cellulase should be regarded as endo-type cellulase, although it hydrolyzed Avicel.
Growth hormone response to growth hormone-releasing hormone in beef cows divergently selected for milk production.

In dairy cattle, increased circulating growth hormone has been associated with selection for greater milk yield. This study tested the hypothesis that beef cows divergently selected for milk production would have differing GH responses to a challenge dose of GHRH. Growth hormone response to a challenge of GHRH was measured in 36 Angus-sired cows ranging from 6 to 10 yr of age. The cows were classified as high milking (n = 16) or low milking (n = 20), on the basis of their sires' milk EPD. Mean milk EPD (in kilograms) were 16.6 and -14.4 for high and low milking cows, respectively. Milk production was estimated by the weigh-suckle-weigh procedure. Blood samples were taken immediately before and 10 min after a clearance dose of 4.5 microg of GHRH/100 kg BW (injected i.v.) and, 3 h later, immediately before and 10 min after a challenge dose of either 1.5 or 4.5 microg of GHRH/100 kg BW. Each animal received both challenge doses, and the doses were randomly assigned across 2 d of blood collection. Serum concentrations of GH and IGF-I were measured by RIA. Serum IGF-I was measured in the baseline blood sample on d 1 of blood collection. A positive relationship (r = 0.35; P = 0.03) was observed between the cows' rankings for each dose of GHRH; that is, high responders to the low dose were high responders to the high dose. Growth hormone response to the 4.5 microg/100 kg BW challenge dose of GHRH was positively related to sire milk EPD (R2 = 0.09; P = 0.03). Response of GH to the 1.5 microg GHRH/100 kg BW challenge dose also tended to be related (P = 0.08) to sire milk EPD of high milking cows. In addition, IGF-I concentrations of high milking cows were inversely related (R2 = 0.24; P = 0.04) to sire milk EPD. Growth hormone response to GHRH challenge may have potential as an additional tool in the evaluation of milk production in beef cattle.
Identification of the meiotic life cycle stage of Trypanosoma brucei in the tsetse fly

Elucidating the mechanism of genetic exchange is fundamental for understanding how genes for such traits as virulence, disease phenotype, and drug resistance are transferred between pathogen strains. Genetic exchange occurs in the parasitic protists Trypanosoma brucei, T. cruzi, and Leishmania major, but the precise cellular mechanisms are unknown, because the process has not been observed directly. Here we exploit the identification of homologs of meiotic genes in the T. brucei genome and demonstrate that three functionally distinct, meiosis-specific proteins are expressed in the nucleus of a single specific cell type, defining a previously undescribed developmental stage occurring within the tsetse fly salivary gland. Expression occurs in clonal and mixed infections, indicating that the meiotic program is an intrinsic but hitherto cryptic part of the developmental cycle of trypanosomes. In experimental crosses, expression of meiosis-specific proteins usually occurred before cell fusion. This is evidence of conventional meiotic division in an excavate protist, and the functional conservation of the meiotic machinery in these divergent organisms underlines the ubiquity and basal evolution of meiosis in eukaryotes.
Molecular ecological approaches to studying the evolutionary impact of selective harvesting in wildlife

Harvesting of wildlife populations by humans is usually targeted by sex, age or phenotypic criteria, and is therefore selective. Selective harvesting has the potential to elicit a genetic response from the target populations in several ways. First, selective harvesting may affect population demographic structure (age structure, sex ratio), which in turn may have consequences for effective population size and hence genetic diversity. Second, wildlife‐harvesting regimes that use selective criteria based on phenotypic characteristics (e.g. minimum body size, horn length or antler size) have the potential to impose artificial selection on harvested populations. If there is heritable genetic variation for the target characteristic and harvesting occurs before the age of maturity, then an evolutionary response over time may ensue. Molecular ecological techniques offer ways to predict and detect genetic change in harvested populations, and therefore have great utility for effective wildlife management. Molecular markers can be used to assess the genetic structure of wildlife populations, and thereby assist in the prediction of genetic impacts by delineating evolutionarily meaningful management units. Genetic markers can be used for monitoring genetic diversity and changes in effective population size and breeding systems. Tracking evolutionary change at the phenotypic level in the wild through quantitative genetic analysis can be made possible by genetically determined pedigrees. Finally, advances in genome sequencing and bioinformatics offer the opportunity to study the molecular basis of phenotypic variation through trait mapping and candidate gene approaches. With this understanding, it could be possible to monitor the selective impacts of harvesting at a molecular level in the future. Effective wildlife management practice needs to consider more than the direct impact of harvesting on population dynamics. Programs that utilize molecular genetic tools will be better positioned to assess the long‐term evolutionary impact of artificial selection on the evolutionary trajectory and viability of harvested populations.
The relationship between the geniculocortical afferents and their cortical target cells during development of the cat's primary visual cortex

To study the prenatal development of connections between the lateral geniculate nucleus (LGN) and the primary visual cortex in the cat, we have examined the relationship between the position of ingrowing afferents from the LGN and their target cells in cortical layers 4 and 6 at various times during the cat's 65 d gestation period and during the first 3 weeks of postnatal life. In 1 series of experiments, the method of transneuronal transport of intraocularly injected tritiated proline (3H-proline), followed by autoradiography, was used to label the developing geniculocortical pathway. In another series, the tritiated thymidine (3H-thymidine) method was employed to keep track of the cells destined for layers 4 and 6 by labeling them on their birthdates (layer 4: embryonic day (E) 37–43; layer 6: E31–36) (Luskin and Shatz, 1985b) and then charting their locations at subsequent times during development. The results of the 2 sets of experiments were compared at corresponding ages. By E39, many of the cells of cortical layer 6 have completed their migrations and are situated within the cortical plate immediately above the subplate. However, the transneuronal labeling pattern indicates that the geniculocotical afferents have not yet arrived within the vicinity of the future visual cortex, but rather are still en route and confined within the optic radiations of the telencephalon. By E42, a week after the first afferents can be detected in the radiations, substantial transneuronal label is found in the subplate immediately below future visual cortex. However, the overlying cortical plate is free of label. Over the next 2 weeks, geniculocortical axons continue to accumulate in the subplate zone, and, in addition, transneuronal label can be found in the marginal zone. By E55 a faint geniculocortical projection can be detected within the cortical plate, but only within its deeper half (future layers 5 and 6), and even then the major portion of the projection is still confined to the subplate. The absence of a projection to cortical layer 4 at these ages is remarkable in view of the results from our 3H-thymidine experiments, which indicate that by E57 the majority of cells destined to belong to layer 4 have already completed their migrations and assumed positions superficial to the cells of layers 5 and 6. By birth, a substantial geniculocortical projection to cortical layer 4 can be detected in the transneuronal autoradiographs. (ABSTRACT TRUNCATED AT 400 WORDS)
The pathology of AIDS.

With an estimated 17,000 cases world wide, the acquired immune deficiency syndrome (AIDS) is pandemic. In addition, for every known case of AIDS, between 50 and 100 people are infected with the AIDS virus (HTLV-III). Although AIDS remains incurable, more and more is being learned about the nature of the virus and the pathogenesis of the disease. There is considerable genetic variation between different isolates of the virus, although a single antibody can be used to detect the virus in all European and North American patients. Observation of the disease in man has triggered tremendous research in animals, especially monkeys, in whom 3 distinct retroviruses have been found. Pre-existing immunosuppression and excessive antigenic stimulation are important factors which predispose people carrying HTLV-III to developing AIDS. Excessive antigenic stimulation is especially relevant among homosexuals with multiple sexual partners and repeated sexually transmitted infections. A positive test implies past experience of the virus and continuing excretion of the virus by the patient. Whether or not counseling at risk groups actually affects their sex behavior was discussed by Mr. J. Green, a clinical psychologist from St. Mary's Hospital, London. He believes that his studies on homosexual patients have shown that counseling did persuade them to change to safer sex. It is important to maintain a high level of suspicion, particularly when a young person in an at risk group presents with a syndrome similar to glandular fever or a pyrexia of unknown origin. Once a patient in hospital is known to have AIDS, full precautions should be taken to protect clinical and laboratory staff, as well as to preserve the patient's dignity and confidentiality.
Human Cell Assays for Synthesis-Dependent Strand Annealing and Crossing over During Double-Strand Break Repair

DNA double-strand breaks (DSBs) are one of the most deleterious types of lesions to the genome. Synthesis-dependent strand annealing (SDSA) is thought to be a major pathway of DSB repair, but direct tests of this model have only been conducted in budding yeast and Drosophila. To better understand this pathway, we developed an SDSA assay for use in human cells. Our results support the hypothesis that SDSA is an important DSB repair mechanism in human cells. We used siRNA knockdown to assess the roles of a number of helicases suggested to promote SDSA. None of the helicase knockdowns reduced SDSA, but knocking down BLM or RTEL1 increased SDSA. Molecular analysis of repair products suggests that these helicases may prevent long-tract repair synthesis. Since the major alternative to SDSA (repair involving a double-Holliday junction intermediate) can lead to crossovers, we also developed a fluorescent assay that detects crossovers generated during DSB repair. Together, these assays will be useful in investigating features and mechanisms of SDSA and crossover pathways in human cells.
Differential expression of proteins in response to the interaction between the pathogen Fusarium graminearum and its host, Hordeum vulgare

Using proteomic techniques, a study aimed at isolating and identifying proteins associated with resistance to fusarium head blight (FHB) was conducted on six barley genotypes of varying resistance. At anthesis, barley spikelets were point inoculated with Fusarium graminearum macroconidial suspensions or mock inoculum. In total, 43 acidic protein spots out of 600 were detected 3 days postinoculation to be differentially expressed due to FHB and were identified. Identification of proteins responsive to FHB included those associated with oxidative burst and oxidative stress response, such as malate dehydrogenase and peroxidases, and pathogenesis‐related (PR). An increase in abundance of PR‐3 or PR‐5 could be associated with the resistant genotypes CI4196, Svansota, and Harbin, as well as the intermediate resistant genotype CDC Bold. On the contrary, the susceptible genotype Stander showed a decrease in abundance of these acidic PR‐proteins. In the susceptible and intermediate resistant genotypes Stander and CDC Bold, as well as CI4196, the increased abundance of proteins associated with an oxidative response might have prepared the terrain for saprophytic fungal invasion. On the contrary, in the resistant sources Harbin and Svansota we did not observed change in abundance of these proteins. Not a single significant change in acidic protein abundance could be detected in Chevron. Three distinct response patterns are reported from these six barley genotypes.
Effect of High Hydrostatic Pressure Applied Before Cryopreservation on the Survival Rate and Quality of Porcine Mesenchymal Stem Cells After Thawing

ABSTRACT The aim of the present study was to examine the effects of varied high hydrostatic pressure (HHP) values on survival rate, proliferation rate, cell multipotency (transcript expression of SOX2, C-MYC, and REX1) and apoptosis (expression of phosphatidylserine (PS), SURVIVIN at the RNA level and BAX at the protein level) of porcine mesenchymal stem cells (MSCs). MSCs were isolated from porcine bone marrow and cultured in vitro. Before cryopreservation and storage in liquid nitrogen, MSCs were subjected to HHP at the varied pressures of 20, 30, 40, 50, or 60 MPa for 1 h at 24°C. Immediately after thawing and after 8 days of in vitro culture, cells were subjected to trypan blue staining, cell counting, real-time Polymerase Chain Reaction (PCR), western blotting, and fluorescence microscopy. BAX protein expression was only estimated immediately after HHP to exclusively examine the impact of HHP on apoptosis of MSCs. The viability of MSC subjected to 40, 50, and 60 MPa and estimated immediately after thawing increased significantly (P < 0.001 for 60 MPa and P < 0.05 for 40 and 50 MPa) in comparison to control. The proliferation rate of MSCs subjected to 40 MPa HHP was significantly higher than in the control group (P < 0.02) after 8 days of in vitro culture. After 8 days of in vitro culture, no significant differences were noted in the survival rates, PS exposure, or levels of SOX2, C-MYC, REX1, and SURVIVIN gene expression in all analyzed groups compared to control. In conclusion: 40–60 MPa HHP has a positive impact by improving cell viability in short term. 20–60 MPa HHP does not induce nor decrease apoptosis in MSCs. Fortunately, HHP does not induce differentiation of MSC. Our results calls for further analysis using HHP values higher than 60 MPa.
Comparison of spiral multidetector CT angiography and myocardial perfusion imaging in the noninvasive detection of functionally relevant coronary artery lesions: first clinical experiences.

UNLABELLED Compared with conventional coronary angiography, spiral multidetector CT (MDCT) angiography has delivered promising accuracy in the detection and validation of coronary lesions. Myocardial perfusion imaging (MPI) using SPECT is an established method for noninvasively assessing the functional significance of coronary stenoses and delivers valuable information for risk stratification. This retrospective analysis compared the accuracies of MDCT angiography and MPI in the detection of hemodynamically relevant lesions of the coronary arteries. METHODS Twenty-five patients with suspected or known coronary artery disease were studied. Electrocardiographically gated MPI and 16-MDCT angiography were performed. Myocardial perfusion images were analyzed by 2 experienced observers, and reversible and fixed perfusion defects were detected and allocated to their corresponding coronary vessels. For the evaluation of MDCT angiography, image quality was determined, and lesions > or = 50% and luminal narrowing < 50% were visually assessed and characterized by 2 independent observers unaware of the results of MPI. RESULTS Ninety-nine coronary vessels were analyzed, and the quality of MDCT angiography images was assessed for 330 coronary segments. Coronary artery diameter was interpretable for 231 (70%) of 330 segments, whereas in 99 (30%) of 330 segments, vessel diameter could not be evaluated because of heavy calcifications, blurring, motion artifacts, or intracoronary stents. MDCT angiography detected stenoses > or = 50% in 15 of 100 coronary arteries. Eight (53%) of 15 stenoses > or = 50% showed reversible or fixed perfusion defects in the corresponding myocardial areas on MPI. Sensitivity, specificity, and negative and positive predictive values were 100%, 87%, 100%, and 29%, respectively, for the ability of MDCT angiography to detect reversible perfusion defects in the corresponding myocardial areas. CONCLUSION MDCT angiography detected myocardial ischemia, as defined by reversible perfusion defects on MPI, with a positive predictive value of 29% in a nonselected study cohort. Compared with MPI alone, MDCT angiography added important morphologic information, but MPI remains mandatory for evaluating the functional relevance of coronary artery lesions.