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61.
The VACTERL-H syndrome is a rare combination of vertebral anomalies, anal atresia, congenital heart defects, tracheo-esophageal fistula, abnormalities of kidneys and limb anomalies together with hydrocephalus. This condition is recognized as a hereditary entity with poor prognosis. We present a newborn weighing 3400 g, born by cesarean section to a 27 years old mother who had had an irregular antenatal follow-up. The patient had severe hydrocephalus, proximal esophageal atresia and distal tracheoesophageal fistula, gastric outlet obstruction, imperforated anus and recto-urethral fistula, patent ductus arterious, a bifid scrotum, a vertebral defect, sacral dimple and central hypothyroidism. The patient had no limb defects. The association of central hypothyroidism and VACTERL-H has previously not been reported.  相似文献   
62.
Zinc (Zn) deficiency is a widespread problem which reduces yield and grain nutritive value in many cereal growing regions of the world. While there is considerable genetic variation in tolerance to Zn deficiency (also known as Zn efficiency), phenotypic selection is difficult and would benefit from the development of molecular markers. A doubled haploid population derived from a cross between the Zn inefficient genotype RAC875-2 and the moderately efficient genotype Cascades was screened in three experiments to identify QTL linked to growth under low Zn and with the concentrations of Zn and iron (Fe) in leaf tissue and in the grain. Two experiments were conducted under controlled conditions while the third examined the response to Zn in the field. QTL were identified using an improved method of analysis, whole genome average interval mapping. Shoot biomass and shoot Zn and Fe concentrations showed significant negative correlations, while there were significant genetic correlations between grain Zn and Fe concentrations. Shoot biomass, tissue and grain Zn concentrations were controlled by a number of genes, many with a minor effect. Depending on the traits and the site, the QTL accounted for 12–81% of the genetic variation. Most of the QTL linked to seedling growth under Zn deficiency and to Zn and Fe concentrations were associated with height genes with greater seedling biomass associated with lower Zn and Fe concentrations. Four QTL for grain Zn concentration and a single QTL for grain Fe concentration were also identified. A cluster of adjacent QTL related to the severity of symptoms of Zn deficiency, shoot Zn concentration and kernel weight was found on chromosome 4A and a cluster of QTL associated with shoot and grain Fe concentrations and kernel weight was found on chromosome 3D. These two regions appear promising areas for further work to develop markers for enhanced growth under low Zn and for Zn and Fe uptake. Although there was no significant difference between the parents, the grain Zn concentration ranged from 29 to 43 mg kg?1 within the population and four QTL associated with grain Zn concentration were identified. These were located on chromosomes 3D, 4B, 6B and 7A and they described 92% of the genetic variation. Each QTL had a relatively small effect on grain Zn concentration but combining the four high Zn alleles increased the grain Zn by 23%. While this illustrates the potential for pyramiding genes to improve grain Zn, breeding for increased grain Zn concentration requires identification of individual QTL with large effects, which in turn requires construction and testing of new mapping populations in the future.  相似文献   
63.
Aluminium stress induces peroxidation of lipids in the plasma membrane, the effect akin to that caused by reactive oxygen species (ROS). ROS have recently been proposed as regulators of redox-dependent ion transport across the plasma membrane during biotic and abiotic stresses, thus contributing to the plant defence system. The aim of this study was to discover whether ROS production is linked to redox-dependent H+ transport system located at the plasma membranes of two near-isogenic lines of wheat (Triticum aestivum L., ET8 = Al-resistant, ES8 = Al-sensitive).The activities of NADPH-dependent ROS synthase and SOD were increased in both wheat lines 15 and 30 min after Al treatments. However, the ROS production was also increased under acidic stress. There was no difference between the two wheat lines in the root-cell plasma membrane capacity to efflux H+ in response to potassium ferricyanide after Al and acidic treatments. In ET8, both stresses led to increases in ROS production and H+ influx.ROS production in wheat seedlings was activated primarily by low pH exposure rather than by the Al stress. ROS production and breakdown in wheat seedlings under Al and acidic stresses appear to be linked to the intracellular metabolic changes rather than to the increased activity of plasma membrane-based NADPH-dependent ROS synthase.Key Words: ion fluxes, reactive oxygen species (ROS), redox system, superoxide dismutase (SOD), Triticum aestivum L., wheat  相似文献   
64.
Cu,Zn superoxide dismutase (SOD1) is an antioxidant enzyme that catalyzes the removal of superoxide radicals generated in various biological oxidations. Amyotrophic lateral sclerosis (ALS) is one of the most common neurodegenerative disorders, occurring in families (FALS) and sporadically (SALS). FALS and SALS are distinguishable genetically but not clinically. More than 100 point mutations in the human SOD 1 gene have been identified that cause FALS. In order to determine the effects of mutant SOD protein, we first cloned wild-type and A4V mutant human SOD1 into Schizosaccharomyces pombe. This study shows viabilities and some antioxidant properties including SOD, catalase, proteasomal activity, and protein carbonyl levels of transformants in SOD1 deleted strain (MN415); and its parental strain (JY741) at different stress conditions. There was no more oxidative damage in the human mutant SOD carrying the transformant strain compared with other strains. These results may help to explain whether ALS progresses as a consequence of cellular oxidative damage.  相似文献   
65.
Cakmak  I.  Erenoglu  B.  Gülüt  K.Y.  Derici  R.  Römheld  V. 《Plant and Soil》1998,202(2):309-315
The effect of varied light intensity (50 – 600 mol m-2 s-1) on the rate of phytosiderophore release was studied under zinc (Zn) deficiency using a bread (Triticum aestivum L. cv. Aroona) and a durum wheat cultivar (Triticum durum Desf. cv. Durati) differing in zinc (Zn) efficiency and under iron (Fe) deficiency using a barley cultivar (Hordeum vulgare L. Europe). Plants were grown under controlled environmental conditions in nutrient solution for 15 days (wheat plants) or 11 days (barley plants). Phytosiderophore release was determined by measuring capacity of root exudates to mobilize copper (Cu) from a Cu-loaded resin.With increasing light intensity visual Zn deficiency symptoms such as whitish-brown lesions on leaf blade developed rapidly and severely in wheat, particularly in the durum cultivar Durati. In wheat plants supplied well with Zn, increases in light intensity from 100 to 600 mol m-2 s-1 did not clearly affect the rate of phytosiderophore release. However, under Zn deficiency increases in light intensity markedly enhanced release of phytosiderophores in Zn-deficient Aroona, but not in Zn-inefficient Durati. When Fe-deficient barley cultivar Europe was grown first at 220 mol m-2 s-1 and then exposed to 600 mol m-2 s-1 for 24 and 48 h, the rate of release of phytosiderophores was enhanced about 4-fold and 7-fold, respectively. Transfer of Fe-deficient plants from 600 to 50 mol m-2 s-1 for 48 h reduced the rate of release of phytosiderophores by a factor of 7. The effect of light on phytosiderophore release was similar regardless of whether the rate of phytosiderophore release was expressed per plant or per unit dry weight of roots.The results demonstrate a particular role of light intensity in phytosiderophore release from roots under both Zn and Fe deficiency. It is suggested that in the studies concerning the role of phytosiderophore release in expression of Zn or Fe efficiency among and within cereals, a special attention should be given to the light conditions.  相似文献   
66.
Extracts of Anthemis hyalina (Ah), Nigella sativa (Ns) and peels of Citrus sinensis (Cs) have been used as folk medicine to fight antimicrobial diseases. To evaluate the effect of extracts of Ah, Ns and Cs on the replication of coronavirus (CoV) and on the expression of TRP genes during coronavirus infection, HeLa-CEACAM1a (HeLa-epithelial carcinoembryonic antigen-related cell adhesion molecule 1a) cells were inoculated with MHV-A59 (mouse hepatitis virus–A59) at moi of 30. 1/50 dilution of the extracts was found to be the safe active dose. ELISA kits were used to detect the human IL-8 levels. Total RNA was isolated from the infected cells and cDNA was synthesized. Fluidigm Dynamic Array nanofluidic chip 96.96 was used to analyze the mRNA expression of 21 TRP genes and two control genes. Data was analyzed using the BioMark digital array software. Determinations of relative gene expression values were carried out by using the 2???Ct method (normalized threshold cycle (Ct) value of sample minus normalized Ct value of control). TCID50/ml (tissue culture infectious dose that will produce cytopathic effect in 50 % of the inoculated tissue culture cells) was found for treatments to determine the viral loads. The inflammatory cytokine IL-8 level was found to increase for both 24 and 48 h time points following Ns extract treatment. TRPA1, TRPC4, TRPM6, TRPM7, TRPM8 and TRPV4 were the genes which expression levels changed significantly after Ah, Ns or Cs extract treatments. The virus load decreased when any of the Ah, Ns or Cs extracts was added to the CoV infected cells with Ah extract treatment leading to undetectable virus load for both 6 and 8hpi. Although all the extract treatments had an effect on IL-8 secretion, TRP gene expression and virus load after CoV infection, it was the Ah extract treatment that showed the biggest difference in virus load. Therefore Ah extract is the best candidate in our hands that contains potential treatment molecule(s).  相似文献   
67.
Understanding the factors influencing the transport of microbial pathogens, such as Salmonella and Escherichia coli, through porous media is critical to protecting drinking water supplies. The production of biofilms, along with individual biofilm-associated components, such as tafi, is believed to hinder transport of microorganisms through soil. This study investigated the relationship between biofilm formation and tafi production and the transport of environmental Salmonella through porous media. Thirty-two Salmonella isolates were initially assayed for their ability to form biofilms, from which a subset of these was selected to represent a range of high and low biofilm-formation potential and tafi formation capabilities. These were subsequently examined in unsaturated sand columns for transport characteristics. No obvious correlation was observed between Salmonella phenotypes and column retention. The results indicated that while transport of well-characterized laboratory E. coli strains can often be hindered by the presence of tafi and the potential to form biofilms, the presence of tafi did not retard the transport of the Salmonella strains.  相似文献   
68.
Cakmak O  Buyuklu F 《Plastic and reconstructive surgery》2006,118(7):1658; author reply 1658-1658; author reply 1659
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69.
One consequence of chronic kidney disease (CKD) is an elevated risk for cancer. There is sufficient evidence to conclude that there is an increased incidence of at least some cancers in kidney-dialysis patients. Cancer risk after kidney transplantation has mainly been attributed to immunosuppressive therapy. There are no data evaluating DNA damage in children with CKD, in dialysis patients, or following kidney transplantation. In this study, the comet assay and the enzyme-modified comet assay - with the use of endonuclease III (Endo III) and formamidopyrimidine glycosylase (FPG) enzymes - were conducted to investigate the basal damage and the oxidative DNA damage as a result of treatment in peripheral blood lymphocytes of children. Children at various stages of treatment for kidney disease, including pre-dialysis patients (PreD) (n=17), regular hemodialysis patients (HD) (n=15), and those that received kidney transplants (Tx) (n=17), comprised the study group. They were compared with age- and gender-matched healthy children (n=20) as a control group. Our results show that the %DNA intensity, a measure of basal damage, was significantly increased in children with CKD (mean ± SD) (5.22 ± 1.57) and also in each of the PreD, HD, and Tx groups [(4.92 ± 1.23), (4.91 ± 1.35), and (5.79 ± 1.94), respectively, vs the healthy children (2.74 ± 2.91) (p<0.001). Significant increases in oxidative DNA damage were only found in the FPG-sensitive sites for the PreD and Tx groups, compared with control and HD groups (p<0.05), suggesting that basal DNA damage was more evident for the PreD, HD, and Tx groups. The findings of the present study indicate a critical need for further research on genomic damage with different endpoints and also for preventive measures and improvements in treatment of pediatric patients, in order to improve their life expectancy.  相似文献   
70.
In this study, a total of 5,094 ticks found on humans were examined in terms of species, development stage, gender, host features and seasonality for a year period. Of these ticks 17 were argasid and 5,077 were ixodid. Predominantly species of the ixodid genera Hyalomma, Dermacentor, Rhipicephalus and Haemaphysalis were found on humans in Ankara (Anatolia). Most abundant were Hyalomma nymphs (29.8%) and adults (28.2%). Primary factors in terms of tick bite risk were region, habitat and season.  相似文献   
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