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Nance-Horan Syndrome (NHS) is a rare X-linked syndrome characterized by congenital cataract which leads to profound vision loss, characteristic dysmorphic features and specific dental anomalies. Microcornea, microphthalmia and mild or moderate mental retardation may accompany these features. Heterozygous females often manifest similarly but with less severe features than affected males. We describe two brothers who have the NHS phenotype and their carrier mother who had microcornea but not cataract. We identified a previously unreported frameshift mutation (c.558insA) in exon 1 of the NHS gene in these patients and their mother which is predicted to result in the incorporation of 11 aberrant amino acids prior to a stop codon (p.E186Efs11X). We also discussed genotype–phenotype correlation according to relevant literature.  相似文献   
3.
During the process of transformation in Hemophilus influenzae integration of donor DNA, i.e. the formation of recombinant DNA, involves the incorporation of single-stranded DNA. Evidence was obtained from cesium chloride density gradient centrifugation of DNA from donor-recipient complexes that integration was accompanied by the formation of hybrid DNA with a density intermediate with respect to heavy, 2H, 15N, donor and light, 1H, 4N recipient DNA. On denaturation the position of the heavy donor DNA moved closer to, but not all the way toward, the density position of the original donor DNA. In addition to supporting the idea of single-stranded incorporation, this evidence suggested that the integrated donor DNA was covalently linked to light recipient DNA. The DNA was taken up in the double-stranded form and no detectable amounts of denatured DNA could be found during the transformation process. However, during the process of integration an amount of donor atoms, equivalent to the amount of hybrid DNA formed, appeared in recipient DNA, and indicated that while one strand of DNA was integrated the other was broken down and resynthesized. The density of the hybrid DNA, as well as rebanding of denatured hybrid, indicated that the size of the integrated piece of DNA was large, approximately 6 x 106 daltons.  相似文献   
4.
Established methods for quantifying experimental Cryptosporidium infection are highly variable and subjective. We describe a new technique using quantitative real-time PCR (qPCR) that can be used to measure in vitro and in vivo laboratory infections with Cryptosporidium. We show for the first time that qPCR permits absolute quantification of the parasite while simultaneously controlling for the amount of host tissue and correlates significantly with established methods of quantification in in vitro and in vivo laboratory models of infection.  相似文献   
5.
To elucidate bacterial population dynamics in an aquifer, we attempted to reveal the impact of protozoan grazing on bacterial productivity and community structure by an in situ incubation experiment using a diffusion chamber. The abundance and vertical distribution of bacteria and protozoa in the aquifer were revealed using wells that were drilled in a sedimentary rock system in Itako, Ibaraki, Japan. The water column in the wells possessed aerobic and anaerobic layers. Active bacterial populations under the grazing pressure of protozoa were revealed through in situ incubation with grazer eliminating experiment by the filtration. On August 19, 2003, the total number of bacteria (TDC) decreased from 1.5 × 106 cells ml? 1 at 2.2 m depth to 3.0 × 105 cells ml? 1 at 10 m depth. The relative contribution of the domain Bacteria to TDC ranged between 63% and 84%. Protozoa existed at a density of 4.2 × 104 to 1.9 × 105 cells ml? 1 in both aerobic and microaerobic conditions. A grazing elimination experiment in situ for 6 days brought about clearly different bacterial community profiles between the 2.2 m and 10 m samples. The bacterial composition of the initial community was predominantly β- and γ -proteobacteria at 2.2 m, while at 10 m β-, α - and γ -proteobacteria represented 56%, 26% and 13% of the community, respectively. The distribution of bacterial abundance, community composition and growth rates in the subsurface were influenced by grazing as well as by geochemical factors (dissolved oxygen and concentrations of organic carbon, methane and sulfate). Results of the in situ incubation experiment suggested that protozoan grazing contributes significantly to bacterial population dynamics.  相似文献   
6.
The development, survival and reproduction of the cabbage aphid, Brevicoryne brassicae (L.) were evaluated at three constant temperatures (20, 25 and 30°C) on cabbage, cauliflower, red cabbage, turnip and radish. The development periods of immature stages ranged from 10.7 d at 20°C to 7.60 d at 30°C for red cabbage. Total percentages of survivorship of immature stages varied from 39.40 and 82.50 within the temperature range of 25–30°C on radish. The average progeny per female was 31.15, 28.95 and 23.77 at 20, 25 and 30°C on cabbage.  相似文献   
7.
Glioblastoma (GBM) is the most common and aggressive intraparenchymal primary brain tumor in adults. The principal reasons for the poor outcomes of GBM are the high rates of recurrence and resistance to chemotherapy. The aim of this study was to determine the role of tailored cellular therapy for GBM with a poor prognosis and compare the activity of dendritic cells (DCs) that have encountered GBM cells. Detecting the correlations between methylation and expression of MGMT and PTEN genes and GBM cancer stem cells (CSCs) markers after co-cultures with a mononuclear cell cocktail are also aims for this study. Allogenic umbilical cord blood (UCB)-derived DCs were labeled with the CD11a and CD123 for immature DCs, and CD80 and CD11c for mature DCs. CD34, CD45, and CD56 cells were isolated from allogenic UCB for using in DCs maturation. GBM CSCs were detected with CD133/1 and CD111 antibodies after co-culture studies. DC activation was carried out via GBM cells including CD133 and CD111 cells and a mononuclear cells cocktail including CD34, CD45, and CD56 natural killer cells. Real-time PCR was performed to detect the expression and promoter methylation status of PTEN and MGMT genes. The expression of CSCs markers was found in all GBM cases, and a statistically significant correlation was found among them after co-culture studies. The most pronounced affinity of DCs to GBM cells was observed at dilutions between 1/4 and 1/256 in co-cultures. There was a statistically significant correlation between cellularity and granularity ratios for CD123 and CD11c. PTEN and MGMT gene expression and methylation values were evaluated with respect to CSCs expression and no statistical significance was found. Activation of DCs might associate with CSCs and the mononuclear cells cocktail including CD34, CD45, and CD56 cells which were obtained from allogenic UCB.  相似文献   
8.
Our aim in this study was to investigate the effect of moderate acute alcohol administration on cysteine protease mediated neuronal apoptosis and nitric oxide production in the traumatic brain injury. A total of 29 adult Sprague–Dawley male rats weighing 250–300 g were used. The rats were allocated into four groups. The first group was the control (sham-operated) group in which only a craniotomy was performed, the others were alcohol, trauma and trauma + alcohol groups. Caspase-3 enzyme activity in the trauma group increased significantly in comparison with the control group. The alcohol given group showed a decreased caspase-3 enzyme activity compared to the trauma group. The level of caspase-3 enzyme activity in the alcohol + trauma group decreased in comparison to the trauma group. SF/FEL ratio of cathepsin-L enzyme activity in the trauma group was significantly higher than in the control group. Our results indicate that moderate alcohol consumption may have protective effects on apoptotic cell death after traumatic brain injury. Protective effects of moderate ethanol consumption might be related to inhibition of lysosomal protease release and nitric oxide production.  相似文献   
9.
Vascular plants have lignified tissues that transport water, minerals, and photosynthetic products throughout the plant. They are the dominant primary producers in terrestrial ecosystems and capture significant quantities of atmospheric carbon dioxide (CO2) through photosynthesis. Some of the fixed CO2 is respired by the plant directly, with additional CO2 lost from rhizodeposits metabolized by root-associated soil microorganisms. Microbially-mediated mineralization of organic nitrogen (N) from plant byproducts (rhizodeposits, dead plant residues) followed by nitrification generates another greenhouse gas, nitrous oxide (N2O). In anaerobic soils, reduction of nitrate by microbial denitrifiers also produces N2O. The plant-microbial interactions that result in CO2 and N2O emissions from soil could be affected by genetic modification. Down-regulation of genes controlling lignin biosynthesis to achieve lower lignin concentration or a lower guaiacyl:syringyl (G:S) ratio in above-ground biomass is anticipated to produce forage crops with greater digestibility, improve short rotation woody crops for the wood-pulping industry and create second generation biofuel crops with low ligno-cellulosic content, but unharvested residues from such crops are expected to decompose quickly, potentially increasing CO2 and N2O emissions from soil. The objective of this review are the following: 1) to describe how plants influence CO2 and N2O emissions from soil during their life cycle; 2) to explain how plant residue chemistry affects its mineralization, contributing to CO2 and N2O emissions from soil; and 3) to show how modification of plant lignin biosynthesis could influence CO2 and N2O emissions from soil, based on experimental data from genetically modified cell wall mutants of Arabidopsis thaliana. Conceptual models of plants with modified lignin biosynthesis show how changes in phenology, morphology and biomass production alter the allocation of photosynthetic products and carbon (C) losses through rhizodeposition and respiration during their life cycle, and the chemical composition of plant residues. Feedbacks on the soil environment (mineral N concentration, soil moisture, microbial communities, aggregation) affecting CO2 and N2O emissions are described. Down-regulation of the Cinnamoyl CoA Reductase 1 (CCR1) gene is an excellent target for highly digestable forages and biofuel crops, but A. thaliana with this mutation has lower plant biomass and fertility, prolonged vegetative growth and plant residues that are more susceptible to biodegradation, leading to greater CO2 and N2O emissions from soil in the short term. The challenge in future crop breeding efforts will be to select tissue-specific genes for lignin biosynthesis that meet commercial demands without compromising soil CO2 and N2O emission goals.  相似文献   
10.
Hyperglycemia-induced oxidative stress leads to diabetes-associated damage to the microvasculature of the brain. Pericytes in close proximity to endothelial cells in the brain microvessels are vital to the integrity of the blood–brain barrier and are especially susceptible to oxidative stress. According to our recently published results, streptozotocin-diabetic mouse brain exhibits oxidative stress and loose pericytes by twelve weeks of diabetes, and cerebral pericytes cultured in high glucose media suffer intracellular oxidative stress and apoptosis. Oxidative stress in diabetes is hypothesized to be caused by reactive oxygen species (ROS) produced during hyperglycemia-induced enhanced oxidative metabolism of glucose (respiration). To test this hypothesis, we investigated the effect of high glucose on respiration rate and ROS production in mouse cerebral pericytes. Previously, we showed that pharmacological inhibition of mitochondrial carbonic anhydrases protects the brain from oxidative stress and pericyte loss. The high glucose-induced intracellular oxidative stress and apoptosis of pericytes in culture were also reversed by inhibition of mitochondrial carbonic anhydrases. Therefore, we extended our current study to determine the effect of these inhibitors on high glucose-induced increases in pericyte respiration and ROS. We now report that both the respiration and ROS are significantly increased in pericytes challenged with high glucose. Furthermore, inhibition of mitochondrial carbonic anhydrases significantly slowed down both the rate of respiration and ROS production. These data provide new evidence that pharmacological inhibitors of mitochondrial carbonic anhydrases, already in clinical use, may prove beneficial in protecting the brain from oxidative stress caused by ROS produced as a consequence of hyperglycemia-induced enhanced respiration.  相似文献   
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