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91.
Cultivated rye (Secale cereale L., 2n = 2x = 14, RR) is an important source of genes for insect and disease resistance in wheat (Triticum aestivum L., 2n = 6x = 42). Rye chromosome arm 1RS of S. cereale 'Kavkaz' originally found as a 1BL.1RS translocation, carries genes for disease resistance (e.g., Lr26, Sr31, Yr9, and Pm8), while 1RS of the S. cereale 'Amigo' translocation (1RSA) carries a single resistance gene for greenbug (Schizaphis graminum Rondani) biotypes B and C and also carries additional disease-resistance genes. The purpose of this research was to identify individual plants that were recombinant in the homologous region of.1AL.1RSV and 1AL.1RSA using both molecular and phenotypic markers. Secale cereale 'Nekota' (1AL.1RSA) and S. cereale 'Pavon 76' (1AL.1RSV) were mated and the F1 was backcrossed to 'Nekota' (1AL.1AS) to generate eighty BC1F2:3 families (i.e., ('Nekota' 1AL.1RSA x 'Pavon 76' 1AL.1RSV) x 'Nekota' 1AL.1AS). These families were genotyped using the secalin-gliadin grain storage protein banding pattern generated with polyacrylamide gel electrophoresis to discriminate 1AL.1AS/1AL.1RS heterozygotes from the 1AL.1RSA+V and 1AL.1AS homozygotes. Segregation of the secalin locus and PCR markers based on the R173 family of rye specific repeated DNA sequences demonstrated the presence of recombinant 1AL.1RSA+V families. Powdery mildew (Blumeria graminis) and greenbug resistance genes on the recombinant 1RSA+V arm were mapped in relation to the Sec-1 locus, 2 additional protein bands, 3 SSRs, and 13 RFLP markers. The resultant linkage map of 1RS spanned 82.4 cM with marker order and spacing showing reasonable agreement with previous maps of 1RS. Fifteen markers lie within a region of 29.7 cM next to the centromere, yet corresponded to just 36% of the overall map length. The map position of the RFLP marker probe mwg68 was 10.9 cM distal to the Sec-1 locus and 7.8 cM proximal to the powdery mildew resistance locus. The greenbug resistance gene was located 2.7 cM proximal to the Sec-1 locus.  相似文献   
92.
ObjectiveA well-established belief regarding inequalities in health around the world is that hypertension and diabetes are higher in groups of lower socioeconomic status. We examined whether rates of hypertension, diabetes, and the coexistence of hypertension and diabetes are higher in people from a lower socioeconomic status than in those from a higher socioeconomic status in Bangladesh.MethodsWe investigated a nationally representative dataset from the 2011 Bangladesh Demographic and Health Survey with objective measures for hypertension and diabetes. A wealth index was constructed from data on household assets using principal components analysis. Chi-square tests and logistic regressions were performed to test the associations between wealth level, hypertension and diabetes.FindingsPeople from the highest wealth quintile were significantly more likely to have hypertension (Adjusted odds ratios [AOR] = 1.65, 95% confidence interval [CI] = 1.22-2.25), diabetes (AOR = 1.81, 95% CI = 1.21-2.71), and the coexistence of hypertension and diabetes (AOR = 2.17, 95% CI = 1.05-4.49) than people from the lowest wealth quintile. The odds of having hypertension, diabetes, and their coexistence were higher for older people, women, people who engaged in less physical labor, and people who were overweight and obese.ConclusionWealthier people, particularly people from the fourth and highest wealth quintiles, should be careful to avoid unhealthy lifestyles to prevent hypertension and diabetes. Health policy makers and planners are urged to target wealthier strata in terms of hypertension and diabetes initiatives while paying special attention to older people, women, people who engage in less physical labor, and individuals who are overweight.  相似文献   
93.
Simultaneous bioelectricity generation and dye degradation was achieved in the present study by using a combined anaerobic-aerobic process. The anaerobic system was a typical single chambered microbial fuel cell (SMFC) which utilizes acid navy blue r (ANB) dye along with glucose as growth substrate to generate electricity. Four different concentrations of ANB (50, 100, 200 and 400 ppm) were tested in the SMFC and the degradation products were further treated in an activated sludge post treatment process. The dye decolorization followed pseudo first order kinetics while the negative values of the thermodynamic parameter ∆G (change in Gibbs free energy) shows that the reaction proceeds with a net decrease in the free energy of the system. The coulombic efficiency (CE) and power density (PD) attained peak values at 10.36% and 2,236 mW/m2 respectively for 200 ppm of ANB. A further increase in ANB concentrations results in lowering of cell potential (and PD) values owing to microbial inhibition at higher concentrations of toxic substrates. Cyclic voltammetry studies revealed a perfect redox reaction was taking place in the SMFC. The pH, temperature and conductivity remain 7.5–8.0, 27(±2°C and 10.6–18.2 mS/cm throughout the operation. The biodegradation pathway was studied by the gas chromatography coupled with mass spectroscopy technique, suggested the preferential cleavage of the azo bond as the initial step resulting in to aromatic amines. Thus, a combined anaerobic-aerobic process using SMFC coupled with activated sludge process can be a viable option for effective degradation of complex dye substrates along with energy (bioelectricity) recovery.  相似文献   
94.
Triazine-2-14C metsulfuron–methyl is a selective, systemic sulfonylurea herbicide. Degradation studies in soils are essential for the evaluation of the persistence of pesticides and their breakdown products. The purpose of the present study was to investigate the degradation of triazine-2-14C metsulfuron–methyl in soil under laboratory conditions. A High Performance Liquid Chromatograph (HPLC) equipped with an UV detector and an on-line radio-chemical detector, plus a Supelco Discovery column (250 x 4.6 mm, 5 μm), and PRP–1 column (305 x 7.0 mm, 10 μm) was used for the HPLC analysis. The radioactivity was determined by a Liquid Scintillation Counter (LSC) in scintillation fluid. The soil used was both sterilized and non-sterilized in order to observe the involvement of soil microbes. The estimated DT50 and DT90 values of metsulfuron-methyl in a non-sterile system were observed to be 13 and 44 days, whereas in sterilized soil, the DT50 and DT90 were 31 and 70 days, respectively. The principal degradation product after 60 days was CO2. The higher cumulative amount of 14CO2 in 14C- triazine in the non-sterilized soil compared to that in the sterile system suggests that biological degradation by soil micro-organisms significantly contributes to the dissipation of the compound. The major routes of degradation were O-demethylation, sulfonylurea bridge cleavage and the triazine “ring-opened.”  相似文献   
95.
Interleukin (IL)-23 and IL-12 are closely related in structure, and these cytokines regulate both innate and adaptive immunity. However, the precise signaling networks that regulate the production of each in Toxoplasma gondii-infected THP-1 monocytic cells, particularly the PI3K/AKT and MAPK signaling pathways, remain unknown. In the present study, T. gondii infection upregulated the expression of IL-23 and IL-12 in THP-1 cells, and both cytokines increased with parasite dose. IL-23 secretion was strongly inhibited by TLR2 monoclonal antibody (mAb) treatment in a dose-dependent manner and by TLR2 siRNA transfection, whereas IL-12 secretion was strongly inhibited by TLR4 mAb treatment dose-dependently and by TLR4 siRNA transfection. IL-23 production was dose-dependently inhibited by the PI3K inhibitors LY294002 and wortmannin, whereas IL-12 production increased dose-dependently. THP-1 cells exposed to live T. gondii tachyzoites underwent rapid p38 MAPK, ERK1/2 and JNK activation. IL-23 production was significantly upregulated by the p38 MAPK inhibitor SB203580 dose-dependently, whereas pretreatment with 10 μM SB203580 significantly downregulated IL-12 production. ERK1/2 inhibition by PD98059 was significantly downregulated IL-23 production but upregulated IL-12 production. JNK inhibition by SP600125 upregulated IL-23 production, but IL-12 production was significantly downregulated dose-dependently. T. gondii infection resulted in AKT activation, and AKT phosphorylation was inhibited dose-dependently after pretreatment with PI3K inhibitors. In T. gondii-infected THP-1 cells, ERK1/2 activation was regulated by PI3K; however, the phosphorylation of p38 MAPK and JNK was negatively modulated by the PI3K signaling pathway. Collectively, these results indicate that IL-23 production in T. gondii-infected THP-1 cells was regulated mainly by TLR2 and then by PI3K and ERK1/2; however, IL-12 production was mainly regulated by TLR4 and then by p38 MAPK and JNK. Our findings provide new insight concerning the intracellular networks of the PI3K/AKT and MAPK signaling cascades for regulating T. gondii-induced IL-23 and IL-12 secretion in human monocytic cells.  相似文献   
96.

Introduction

Tuberculosis (TB) is a significant public health problem and the diagnosis in human immunodeficiency virus (HIV)—infected individuals is challenging. The use of mycobacterial culture remains an important complementary tool and optimizing it has important benefits. We sought to determine the effect of an increase in the number of specimens evaluated, addition of nutritional supplementation to the culture medium, sputum appearance and volume on diagnostic yield and time to detection of pulmonary TB among smear-negative, HIV-infected adults.

Methods

In this prospective study conducted at the Tshwane District Hospital and Academic TB Laboratory, Pretoria, South Africa we collected three sputum specimens an hour apart from presumptive TB cases at an antiretroviral treatment site. We analysed specimens from 236 patients. Specimen appearance and volume were recorded. All specimens were processed for culture using both standard and supplemented media.

Results

A single specimen identified 79% of PTB cases using standard media; the second and third specimens added 12.5% and 8.3% respectively. Media supplementation, sputum appearance and specimen volume had no effect on culture yield or contamination rates. The mean time to detection was reduced from 19.8 days in standard cultures to 11.8 days in nutrient supplemented cultures (p = 0.002). For every 1 ml increase in sputum volume, time to detection was decreased by a factor of 0.797 (p = 0.011).

Conclusion

Use of an inexpensive culture supplement substantially reduced time to detection and could contribute to reducing treatment delay among HIV-infected cases.  相似文献   
97.

Objectives

Recent evidence suggests that suicidal ideation is increased among university students, it is essential to increase our knowledge concerning the etiology of suicidal ideation among university students. This study was conducted to examine the relationships between problem-solving skills appraisal, hardiness, and suicidal ideation among university students. In addition, this study was conducted to examine problem-solving skills appraisal (including the three components of problem-solving confidence, approach-avoidance style, and personal control of emotion) as a potential mediator between hardiness and suicidal ideation.

Methods

The participants consisted of 500 undergraduate students from Malaysian public universities.

Results

Structural Equation Modelling (SEM) estimated that undergraduate students with lower hardiness, poor problem-solving confidence, external personal control of emotion, and avoiding style was associated with higher suicidal ideation. Problem-solving skills appraisal (including the three components of problem-solving confidence, approach-avoidance style, and personal control of emotion) partially mediated the relationship between hardiness and suicidal ideation.

Conclusion

These findings underline the importance of studying mediating processes that explain how hardiness affects suicidal ideation.  相似文献   
98.
The pine processionary moth Thaumetopoea pityocampa (Den. & Schiff.) is one of the most harmful pests to pine species in Mediterranean countries including Turkey. Caterpillars of T. pityocampa are not only significantly harmful to forest trees but also responsible for various allergic reactions in humans and animals. In this study, in order to find a more effective and safe biological control agent against T. pityocampa, we investigated fungal pathogens of T. pityocampa in the Black Sea Region of Turkey and tested their pathogenicity on it. Five different fungi were isolated and identified based on their morphological and molecular characteristics including ITS and partial sequence of EF1-[alpha]. Based on these characteristics, four isolates were identified as Beauveria bassiana cf. Clade C (Rehner and Buckley in Mycologia 97:84–98, 2005) and one isolate was identified as Beauveria bassiana. Among these isolates, B. bassiana KTU-24, B. bassiana cf. Clade C KTU-66 and KTU-67 showed the highest virulence with 100% mortality within 10 days after application. B. bassiana isolate KTU-24 produced the highest mycosis value with %100. Consequently, B. bassiana KTU-24 seems to be good candidate for further investigation as a possible biological control agent against this pest.  相似文献   
99.
Exopolysaccharides (EPS) from lactic acid bacteria contribute to specific rheology and texture of fermented milk products and finds applications even in non-dairy foods and in therapeutics. Box-Behnken model of response surface methodology (RSM) was employed to formulate the production medium for exopolysaccharide (EPS). FT-IR spectral analysis of the purified EPS from Lactobacillus plantarum MTCC 9510 revealed prominent characteristic groups corresponding to polyhydric alcohols. The degradation temperature (Td) of the polysaccharide was found to be 260°C with the help of thermo gravimetric analysis (TGA). Structure elucidation of the EPS showed that it consists of a trisaccharide repeating unit of α-d-glucose, β-d-glucose and α-d-mannose.  相似文献   
100.

Background and Aims

Micronutrient malnutrition, particularly zinc and iron deficiency, afflicts over three billion people worldwide due to low dietary intake. In the current study, wild emmer wheat (Triticum turgidum ssp. dicoccoides), the progenitor of domesticated wheat, was tested for (1) genetic diversity in grain nutrient concentrations, (2) associations among grain nutrients and their relationships with plant productivity, and (3) the association of grain nutrients with the eco-geographical origin of wild emmer accessions.

Methods

A total of 154 genotypes, including wild emmer accessions from across the Near Eastern Fertile Crescent and diverse wheat cultivars, were characterized in this 2-year field study for grain protein, micronutrient (zinc, iron, copper and manganese) and macronutrient (calcium, magnesium, potassium, phosphorus and sulphur) concentrations.

Key Results

Wide genetic diversity was found among the wild emmer accessions for all grain nutrients. The concentrations of grain zinc, iron and protein in wild accessions were about two-fold greater than in the domesticated genotypes. Concentrations of these compounds were positively correlated with one another, with no clear association with plant productivity, suggesting that all three nutrients can be improved concurrently with no yield penalty. A subset of 12 populations revealed significant genetic variation between and within populations for all minerals. Association between soil characteristics at the site of collection and grain nutrient concentrations showed negative associations between soil clay content and grain protein and between soil-extractable zinc and grain zinc, the latter suggesting that the greatest potential for grain nutrient minerals lies in populations from micronutrient-deficient soils.

Conclusions

Wild emmer wheat germplasm offers unique opportunities to exploit favourable alleles for grain nutrient properties that were excluded from the domesticated wheat gene pool.  相似文献   
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