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951.

Background

Risk factors for ischemic stroke are mostly known, but it is still unclear in most countries, what are their combined population-attributable risk percent (PAR%). In a case-control study the individual odds ratios (ORs) and the individual and combined PAR%, including risk factors not addressed in previous studies were estimated.

Methods

Cases and controls were selected from patients attending to an emergency department. Cases were patients aged with 45 years or more with the first episode of ischemic stroke, characterized by a focal neurological deficit or change in the mental status occurring during the previous 24 hours. Controls, matched to cases by age and gender, were selected from patients without neurological complaints.

Results

133 cases and 272 controls were studied. Odds ratios for ischemic stroke were: atrial fibrillation (27.3; CI 95% 7.5–99.9), left ventricular hypertrophy (20.3; CI 95% 8.8–46.4), history of hypertension (11.2; CI 95% 5.4–23.3), physical inactivity (6.6; CI 95% 3.3–13.1), low levels of HDL-cholesterol (5.0; CI 95%2.8–8.9), heavy smoking (2.8; CI 95% 1.5–5.0), carotid bruit (2.5; CI 95% 1.3–4.6), diabetes (2.4; CI 95% 1.4–4.0) and alcohol abuse (2.1; CI 95% 1.1–4.0), The combination of these risk factors accounted for 98.9% (95% CI; 96.4%–99.7%) of the PAR% for all stroke.

Conclusions

Nine risk factors, easily identified, explain almost 100% of the population attributable risk for ischemic stroke.  相似文献   
952.
In spite of the many advances in haplotyping methods, it is still very difficult to characterize rare haplotypes in tissues and different environmental samples or to accurately assess the haplotype diversity in large mixtures. This would require a haplotyping method capable of analyzing the phase of single molecules with an unprecedented throughput. Here we describe such a haplotyping method capable of analyzing in parallel hundreds of thousands single molecules in one experiment. In this method, multiple PCR reactions amplify different polymorphic regions of a single DNA molecule on a magnetic bead compartmentalized in an emulsion drop. The allelic states of the amplified polymorphisms are identified with fluorescently labeled probes that are then decoded from images taken of the arrayed beads by a microscope. This method can evaluate the phase of up to 3 polymorphisms separated by up to 5 kilobases in hundreds of thousands single molecules. We tested the sensitivity of the method by measuring the number of mutant haplotypes synthesized by four different commercially available enzymes: Phusion, Platinum Taq, Titanium Taq, and Phire. The digital nature of the method makes it highly sensitive to detecting haplotype ratios of less than 1:10,000. We also accurately quantified chimera formation during the exponential phase of PCR by different DNA polymerases.  相似文献   
953.

Background

The impact of early postnatal androgen exposure on female laryngeal tissue may depend on certain characteristics of this exposure. We assessed the impact of the dose, duration, and timing of early androgen exposure on the vocal development of female subjects who had been treated for adrenocortical tumor (ACT) in childhood.

Methods

The long-term effects of androgen exposure on the fundamental vocal frequency (F0), vocal pitch, and final height and the presence of virilizing signs were examined in 9 adult (age, 18.4 to 33.5 years) and 10 adolescent (13.6 to 17.8 years) female ACT patients. We also compared the current values with values obtained 0.9 years to 7.4 years after these subjects had undergone ACT surgery, a period during which they had shown normal androgen levels.

Results

Of the 19 subjects, 17 (89%) had been diagnosed with ACT before 4 years of age, 1 (5%) at 8.16 years, and 1 (5%) at 10.75 years. Androgen exposure (2 to 30 months) was sufficiently strong to cause pubic hair growth in all subjects and clitoromegaly in 74% (14/19) of the subjects, but did not reduce their height from the target value. Although androgen exposure induced a remarkable reduction in F0 (132 Hz) and moderate pitch virilization in 1 subject and partial F0 virilization, resulting in F0 of 165 and 169 Hz, in 2 subjects, the majority had normal F0 ranging from 189 to 245 Hz.

Conclusions

Female laryngeal tissue is less sensitive to androgen exposure between birth and adrenarche than during other periods. Differential larynx sensitivity to androgen exposure in childhood and F0 irreversibility in adulthood are age-, concentration-, duration-, and timing-dependent events that may also be affected by exposure to inhibitory or stimulatory hormones. Further studies are required to better characterize each of these factors.  相似文献   
954.
Constraint-based models of biochemical reaction networks require experimental validation to test model-derived hypotheses and iteratively improve the model. Physiological and proteomic analysis of Thermotoga neapolitana growth on cellotetraose was conducted to identify gene products related to growth on cellotetraose to improve a constraint-based model of T. neapolitana central carbon metabolism with incomplete cellotetraose pathways. In physiological experiments comparing cellotetraose to cellobiose and glucose as growth substrates, product formation yields on cellotetraose, cellobiose, and glucose were similar; however cell yields per mol carbon consumed were higher on cellotetraose than on cellobiose or glucose. Proteomic analysis showed increased expression of several proteins from cells grown on cellotetraose compared with glucose cell cultures, including cellobiose phosphorylase (CTN_0783), endo-1,4-β-glucosidase (CTN_1106), and an ATP-binding protein (CTN_1296). The CTN_1296 gene product should be evaluated further for participation in cellotetraose metabolism and is included as one of two hypothetical gene-protein-reaction associations in the T. neapolitana constraint-based model to reinstate cellotetraose metabolism in model simulations.  相似文献   
955.
Kappaphycus alvarezii is a red alga that is commercially important as a source of carrageenan. Since K. alvarezii presents large phenotypic plasticity and rarely develops reproductive structures in culture, identification of gametophytic and tetrasporophytic phases in cultivation systems are difficult. The aim of this study was to determine the ploidy of three K. alvarezii strains previously identified as brown “tetrasporophyte”, brown “gametophyte” and “Edison de Paula” (EP). Nuclei from these strains were stained with DAPI, and analyzed using confocal fluorescence microscopy and ImageJ software. The brown “tetrasporophyte” had the highest nuclear fluorescence intensity, consistent with a diploid tetrasporophyte (2N). The brown “gametophyte” and “EP” strains had nuclear fluorescence intensities of 55.78% and 57.10% in relation to the tetrasporophyte, respectively, consistent with haploid gametophytes (N). The present study demonstrated that this technique can be used as a rapid and effective tool to distinguish between haploid (gametophytic) and diploid (tetrasporophytic) plants of K. alvarezii, in addition to help identify new strains developed through alterations of ploidy level.  相似文献   
956.
We studied, in the rat brain, the synaptosomal and microsomal membrane fractions of Cl ion-activated, Mg2+-dependent ATPase, satisfying the necessary kinetic peculiarities of transport ATPases, by a novel method of kinetic analysis of the multisite enzyme systems: (1) the [Mg-ATP] complex constitutes the substrate of the enzymic reaction; (2) the V = f(Cl) dependence-reflecting curve is bell-shaped; (3) substrate dependence, V = f(S), curves at a constant concentration of free ligands (Mgf, ATPf, Cl); (4) as known from the literature, in the process of reaction a phosphorylated intermediate is formed (Gerencser, Crit Rev Biochem Mol Biol 31:303–337, 1996). We report on the Cl-ATPase molecular mechanism and its place in the “P-type ATPase” classification.  相似文献   
957.
Bispecific antibodies and antibody fragments are a new class of therapeutics increasingly utilized in the clinic for T cell recruitment (catumaxomab anti-EpCAM/CD3 and blinatumomab anti-CD19/CD3), increase in the selectivity of targeting, or simultaneous modulation of multiple cellular pathways. While the clinical potential for certain bispecific antibody formats is clear, progress has been hindered because they are often difficult to manufacture, may suffer from suboptimal pharmacokinetic properties, and may be limited due to potential immunogenicity issues. Current state-of-the-art human IgG-like bispecific technologies require co-expression of two heavy chains with a single light chain, use crossover domains to segregate light chains, or utilize scFv (single-chain fragment variable)-Fc fusion. We have engineered both human IgG1 and IgG2 subtypes, with minimal point mutations, to form full-length bispecific human antibodies with high efficiency and in high purity. In our system, the two antibodies of interest can be expressed and purified separately, mixed together under appropriate redox conditions, resulting in a formation of a stable bispecific antibody with high yields. With this approach, it is not necessary to generate new antibodies that share a common light chain, therefore allowing the immediate use of an existing antibody regardless of whether it has been generated via standard hybridoma or display methods. We demonstrate the generality of the approach and show that these bispecific antibodies have properties similar to those of wild-type IgGs, and we further demonstrate the utility of the technology with an example of a CD3/CD20 bispecific antibody that effectively depletes B cells in vitro and in vivo.  相似文献   
958.
Angiosperm and gymnosperm plants evolved from a common ancestor about 300 million years ago. Apart from morphological and structural differences in embryogenesis and seed origin, a set of embryogenesis-regulating genes and the molecular mechanisms involved in embryo development seem to have been conserved alike in both taxa. Few studies have covered molecular aspects of embryogenesis in the Brazilian pine, the only economically important native conifer in Brazil. Thus eight embryogenesis-regulating genes, viz., ARGONAUTE 1, CUP-SHAPED COTYLEDON 1, WUSCHEL-related WOX, S-LOCUS LECTIN PROTEIN KINASE, SCARECROW-like, VICILIN 7S, LEAFY COTYLEDON 1, and REVERSIBLE GLYCOSYLATED POLYPEPTIDE 1, were analyzed through semi-quantitative RT-PCR during embryo development and germination. All the eight were found to be differentially expressed in the various developmental stages of zygotic embryos, seeds and seedling tissues. To our knowledge, this is the first report on embryogenesis-regulating gene expression in members of the Araucariaceae family, as well as in plants with recalcitrant seeds.  相似文献   
959.
Concentrations of four metals (Cu, Zn, Pb, and Cd) in the sediments of the Anzali Lagoon in the northern part of Iran were determined to evaluate the level of contamination and spatial distribution. The sediments were collected from 21 locations in the lagoon. At each lagoon site a core, 60 cm long, was taken. The ranges of the measured concentrations in the sediments are as follows: 17–140 mg kg?1 for Cu, 20–113 mg kg?1 for Zn, 1–37 mg kg?1 for Pb and 0.1–3.5 mg kg?1 for Cd in surficial (0-20 cm) and 16–87 mg kg?1 for Cu, 28.5–118 mg kg?1 for Zn, 3–20 mg kg?1 for Pb and 0.1–3.5 mg kg?1 for Cd in deep (40–60 cm) sediments. The results of the geoaccumulation index (Igeo) show that Cd causes moderate to heavy pollution in most of the study area. Environmental risk evaluation showed that the pollution in the Anzali Lagoon is moderate to considerable and the ranking of the contaminants followed the order: Cd > Cu > Pb > Zn. Some locations present severe pollution by metals depending on the sources, of which sewage outlets and phosphate fertilizers are the main sources of contaminants to the area.  相似文献   
960.
The aims of the present study were to investigate the effects of simple and microencapsulated Lactobacillus acidophilus as probiotic with or without inulin as prebiotic on meat quality of broiler infected by avian influenza virus (H9N2). Two hundred-day-old chicks were randomly allocated into 14 groups based on simple, microencapsulated probiotic and prebiotic and based on vaccination and challenge with H9N2 virus. Groups 1–7 contained 20 chicks, and groups 8–12 and 14 contained 10 chicks. Group 13 was derived from group 1 with 10 chicks at challenge day with avian influenza virus (AIV). Half of the groups were vaccinated by H9N2 vaccine on day 5. All groups except the negative control and positive vaccine control were challenged with 106.5 EID50 of low-virulence H9N2 AIV at day 21. Each bird was received 109 CFU of simple or microencapsulated probiotic on days 0 and 17 by gavage. Prebiotic as dose as 0.1 % of feed weight was used daily. Increase in water-holding capacity, dry matter, ash and protein content, and decrease in dripping loss plus beneficial changes in lightness and redness of breast meat were detected in response to probiotic especially microencapsulated synbiotic. In conclusion, probiotic alone or with prebiotic was able to improve the physicochemical properties of chicken breast muscle in both healthy and AIV-infected chickens.  相似文献   
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