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11.
Mineral nutrient malnutrition, and particularly deficiency in zinc and iron, afflicts over 3 billion people worldwide. Wild emmer wheat, Triticum turgidum ssp. dicoccoides, genepool harbors a rich allelic repertoire for mineral nutrients in the grain. The genetic and physiological basis of grain protein, micronutrients (zinc, iron, copper and manganese) and macronutrients (calcium, magnesium, potassium, phosphorus and sulfur) concentration was studied in tetraploid wheat population of 152 recombinant inbred lines (RILs), derived from a cross between durum wheat (cv. Langdon) and wild emmer (accession G18-16). Wide genetic variation was found among the RILs for all grain minerals, with considerable transgressive effect. A total of 82 QTLs were mapped for 10 minerals with LOD score range of 3.2–16.7. Most QTLs were in favor of the wild allele (50 QTLs). Fourteen pairs of QTLs for the same trait were mapped to seemingly homoeologous positions, reflecting synteny between the A and B genomes. Significant positive correlation was found between grain protein concentration (GPC), Zn, Fe and Cu, which was supported by significant overlap between the respective QTLs, suggesting common physiological and/or genetic factors controlling the concentrations of these mineral nutrients. Few genomic regions (chromosomes 2A, 5A, 6B and 7A) were found to harbor clusters of QTLs for GPC and other nutrients. These identified QTLs may facilitate the use of wild alleles for improving grain nutritional quality of elite wheat cultivars, especially in terms of protein, Zn and Fe.  相似文献   
12.
Genetic factors that contribute to the risk of breast cancer are largely not known and association studies have revealed several genes with low penetrance risk alleles for breast cancer. Analysis of these genes may provide important information on the risk factors affecting carcinogenesis. Variations in the ARLTS1, RAD51 and MDM2 genes have been associated with increased risk of different cancer types but for breast cancer the results are not consistent. In this study we investigated the role of the allelic variants in candidate genes acting in the tumor suppressor, DNA repair and p53 pathways as risk factors for familial breast cancer in 147 patients displaying characteristics of familial disease. Presence of the polymorphic variants were investigated by amplification of the corresponding regions and restriction fragment length polymorphism analysis. Genotype and allele frequencies in the patients were significantly different for all three variants. Our results indicate that the polymorphic variants might affect individual susceptibility towards breast cancer.  相似文献   
13.
BackgroundExercise is associated with major benefits in patients with rheumatic diseases for both cardiovascular and rheumatic status. However, information about exercise generally is not collected systematically in routine rheumatology care. A multidimensional health assessment questionnaire (MDHAQ), which was designed for busy clinical settings, includes a query about exercise status. We analyzed possible associations between change in MDHAQ exercise scores and other MDHAQ measures in patients with various rheumatic diseases over one year.MethodsIn one rheumatology clinical setting, all patients, regardless of diagnosis, complete an MDHAQ before seeing a rheumatologist. The MDHAQ includes scores for physical function, pain, and patient global estimate, compiled into an index, routine assessment of patient index data (RAPID3), as well as a self-report joint count and a query about exercise. Patients were classified into four groups according to their exercise status at baseline and one year later as: EXER-Yes (regular exercise), EXER-Yes; EXER-No (no regular exercise), EXER-Yes; EXER-Yes, EXER-No; and EXER-No, EXER-No. These groups were compared using the chi square and Kruskal-Wallis tests and analysis of variance (ANOVA).ResultsPatients who reported regular exercise at baseline were younger, had higher formal education, and better clinical status than other patients. The EXER-No, EXER-Yes group had greater improvement in other MDHAQ variables than patients in the other three groups. By contrast, the EXER-Yes, EXER-No group was the only group with poorer status one year later.ConclusionsThe MDHAQ exercise query indicates that regular exercise is associated with better clinical status. Patients in the EXER-No, EXER-Yes group reported the best clinical improvement, although it is not known whether exercise preceded or followed the improved clinical status.  相似文献   
14.
The gaseous signalling molecule nitric oxide (NO) is involved in various physiological processes including regulation of blood pressure, immunocytotoxicity and neurotransmission. In the mammalian olfactory bulb (OB), NO plays a role in the formation of olfactory memory evoked by pheromones as well as conventional odorants. While NO generated by the neuronal isoform of NO synthase (nNOS) regulates neurogenesis in the olfactory epithelium, NO has not been implicated in olfactory signal transduction. We now show the expression and function of the endothelial isoform of NO synthase (eNOS) in mature olfactory sensory neurons (OSNs) of adult mice. Using NO-sensitive micro electrodes, we show that stimulation liberates NO from isolated wild-type OSNs, but not from OSNs of eNOS deficient mice. Integrated electrophysiological recordings (electro-olfactograms or EOGs) from the olfactory epithelium of these mice show that NO plays a significant role in modulating adaptation. Evidence for the presence of eNOS in mature mammalian OSNs and its involvement in odorant adaptation implicates NO as an important new element involved in olfactory signal transduction. As a diffusible messenger, NO could also have additional functions related to cross adaptation, regeneration, and maintenance of MOE homeostasis.  相似文献   
15.
Micronutrient malnutrition afflicts over three billion people worldwide and the numbers are continuously increasing. Developing genetically micronutrient-enriched cereals, which are the predominant source of human dietary, is essential to alleviate malnutrition worldwide. Wheat chromosome 6B derived from wild emmer wheat [ Triticum turgidum ssp. dicoccoides (Körn.) Thell] was previously reported to be associated with high Zn concentration in the grain. In the present study, recombinant chromosome substitution lines (RSLs), previously constructed for genetic and physical maps of Gpc-B1 (a 250-kb locus affecting grain protein concentration), were used to identify the effects of the Gpc-B1 locus on grain micronutrient concentrations. RSLs carrying the Gpc-B1 allele of T. dicoccoides accumulated on average 12% higher concentration of Zn, 18% higher concentration of Fe, 29% higher concentration of Mn and 38% higher concentration of protein in the grain as compared with RSLs carrying the allele from cultivated wheat ( Triticum durum ). Furthermore, the high grain Zn, Fe and Mn concentrations were consistently expressed in five different environments with an absence of genotype by environment interaction. The results obtained in the present study also confirmed the previously reported effect of the wild-type allele of Gpc-B1 on earlier senescence of flag leaves. We suggest that the Gpc-B1 locus is involved in more efficient remobilization of protein, zinc, iron and manganese from leaves to the grains, in addition to its effect on earlier senescence of the green tissues.  相似文献   
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17.
The pathophysiological mechanism behind the link between antipsychotic drugs and sexual dysfunction is still unknown. The goal of this research is to compare the potential effects of antipsychotics on the male reproductive system. Fifty rats were randomly assigned into the five groups indicated: Control, Haloperidol, Risperidone, Quetiapine and Aripiprazole. Sperm parameters were significantly impaired in all antipsychotics-treated groups. Haloperidol and Risperidone significantly decreased the level of testosterone. All antipsychotics had significantly reduced inhibin B level. A significant reduction was observed in SOD activity in all antipsychotics-treated groups. While GSH levels diminished, MDA levels were rising in the Haloperidol and Risperidone groups. Also, the GSH level was significantly elevated in the Quetiapine and Aripiprazole groups. By causing oxidative stress and altering hormone levels, Haloperidol and Risperidone are damaging to male reproductivity. This study represents useful starting point for exploring further aspects of the underlying mechanisms reproductive toxicity of antipsychotics.  相似文献   
18.
Herpes simplex virus type-1 (HSV-1) and type-2 (HSV-2) are among the most "successful" pathogens and code for a variety of proteins to direct the apoptosis/necrosis responses of the cells they infect. Nitric oxide (NO) is an important intracellular signaling molecule in pathological processes. Acyclovir (ACV) is a chain terminator that targets the viral DNA polymerase as an antiviral agent. In this study, NO signals, and apoptosis/necrosis responses of HEp-2 cells were compared when infected by HSV-1 and -2 for 24 hours against non toxic doses (starting from 48.8, 24.4, 12.2, 6.1, 3 to 1.5 microg/mL) of ACV. In 48.8, 24.4 and 12.2 microg/mL of ACV, HSV-1 had an "upregulating effect" whereas HSV-2 had a "downregulating effect" on NO production, and in 6.1, 3 and 1.5 microg/mL of ACV HSV-1 had a "down-regulating effect" whereas HSV-2 had an "upregulating effect" on NO responses (HSV-1 had a "downregulating effect" on NO production whereas HSV-2 had an "upregulating effect" on NO production without any ACV). In 48.8, 24.4 and 12.2 microg/mL of ACV, HSV-1 had an "anti-apoptotic effect" whereas HSV-2 had a stimulation on "apoptotic effect", and in 6.1, 3 and 1.5 microg/mL of ACV HSV-1 had an "apoptotic effect" and HSV-2 turned to "its natural viral apoptotic effect level" (HSV-1 had an "natural viral apoptotic effect" whereas HSV-2 had a "natural viral apoptotic effect" on apoptosis response without any ACV). In 48.8, and 24.4 microg/mL of ACV, HSV-1 had significant "necrotic effect" on necrotic cellular death, "necrosis" increased in 12.2, 6.1, 3 and 1.5 microg/mL of ACV (HSV-1 had a negligible "necrotic effect" on HEp-2 cells alone), and HSV-2 had a "natural viral necrotic effect" alone; and also in all non toxic ACV concentrations. These results showed that HSV-1 and -2 had different "strategies" on apoptosis/necrosis and NO with and without non toxic ACV. These differences deserve further studies in order to explain the interactions between apoptotic/anti apoptotic, necrotic genes and NO, and ACV in HSV-1 and HSV-2 infections respectively.  相似文献   
19.
The simultaneous detection of nitric oxide and glutamate using an array of individually addressable electrodes, in which the individual electrodes in the array were suitably modified with a highly sensitive nitric oxide sensing chemistry or a glutamate oxidase/redox hydrogel-based glutamate biosensor is presented. In a sequence of modification steps one of the electrodes was covered first with a positively charged Ni porphyrin entrapped into a negatively charged electrodeposition paint followed by the manual modification of the second working electrode by a bienzyme sensor architecture based on crosslinked redox hydrogels with entrapped peroxidase and glutamate oxidase. Adherently growing C6-glioma cells were grown on membrane inserts and placed in close distance to the modified sensor surfaces. The current responses recorded at each electrode after stimulation of glutamate and NO release by means of K+ and bradykinin clearly demonstrate the ability of the individual electrode in the array to detect the analyte towards which its sensitivity and selectivity was targeted without interference from the neighbouring electrode or other analytes present in the test mixture.  相似文献   
20.
An array of electrodes on which cells could be grown directly was fabricated using silicon anisotropic etching and a thick-photoresist process and employed for the detection of nitric oxide (NO) released from a population of adherently growing human umbilical vein endothelial cells (HUVEC). The electrodes are tip-shaped and are 40 microm high of which only the top 15 microm are exposed Pt-tips. After electrochemical induced modification of the exposed Pt tips using Ni phthalocyanine the individual addressable electrode tips were sensitive and selective for the detection of NO at an applied constant potential of 750 mV. The silicon nitride insulation of the lower part of the tip electrodes prevented the death of the cells upon the application of the working potential at which NO was detected. It also helped to avoid the perturbation of the integrity of the sensing chemistry imparted on the electrode surface that could have resulted from the contact of the adherently growing cells with the active electrode surface. The release of nitric oxide from HUVEC was successfully monitored with different numbers of tip electrodes simultaneously connected as combined working electrode.  相似文献   
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