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201.
Madec Y Germanaud D Moya-Alvarez V Alkassoum W Issa A Amadou M Tchiombiano S Pizzocolo C Huber F Diallo S Abdoulaye-Mamadou R 《PloS one》2011,6(7):e22787
Background
In developing countries, malnutrition is a contributing factor in over 50% of child deaths. Mortality rates are higher in underweight children, and HIV-infection is known to increase underweight. Our goals were to evaluate the prevalence of HIV among children hospitalised for severe malnutrition (SM) at the Niamey national hospital (Niger), and to compare renutrition and mortality by HIV-status.Methods
Retrospective study based on all children <5 years hospitalised for SM between January 1st 2008 and July 1st 2009. HIV-prevalence was the ratio of HIV+ children on the number of children tested. Duration of renutrition and mortality were described using survival curves.Results
During the study period, 477 children were hospitalised for SM. HIV testing was accepted in 470 (98.5%), of which 40 were HIV+ (HIV prevalence (95% confidence interval) of 8.6% (6.2–11.5)). Duration of renutrition was longer in HIV+ than HIV− children (mean: 22 vs. 15 days; p = 0.003). During renutrition, 8 (20%) and 61 (14%) HIV+ and HIV− children died, respectively (p = 0.81).Conclusion
Around 9% of children hospitalised for severe malnutrition were HIV infected, while in Niger HIV prevalence in adults is estimated at 0.8%. This pleads for wider access to HIV testing in this population. 相似文献202.
203.
Konishi K Watanabe Y Shen L Guo Y Castoro RJ Kondo K Chung W Ahmed S Jelinek J Boumber YA Estecio MR Maegawa S Kondo Y Itoh F Imawari M Hamilton SR Issa JP 《PloS one》2011,6(11):e27889
Background
The contribution of DNA methylation to the metastatic process in colorectal cancers (CRCs) is unclear.Methods
We evaluated the methylation status of 13 genes (MINT1, MINT2, MINT31, MLH1, p16, p14, TIMP3, CDH1, CDH13, THBS1, MGMT, HPP1 and ERα) by bisulfite-pyrosequencing in 79 CRCs comprising 36 CRCs without liver metastasis and 43 CRCs with liver metastasis, including 16 paired primary CRCs and liver metastasis. We also performed methylated CpG island amplification microarrays (MCAM) in three paired primary and metastatic cancers.Results
Methylation of p14, TIMP3 and HPP1 in primary CRCs progressively decreased from absence to presence of liver metastasis (13.1% vs. 4.3%; 14.8% vs. 3.7%; 43.9% vs. 35.8%, respectively) (P<.05). When paired primary and metastatic tumors were compared, only MGMT methylation was significantly higher in metastatic cancers (27.4% vs. 13.4%, P = .013), and this difference was due to an increase in methylation density rather than frequency in the majority of cases. MCAM showed an average 7.4% increase in DNA methylated genes in the metastatic samples. The numbers of differentially hypermethylated genes in the liver metastases increased with increasing time between resection of the primary and resection of the liver metastasis. Bisulfite-pyrosequencing validation in 12 paired samples showed that most of these increases were not conserved, and could be explained by differences in methylation density rather than frequency.Conclusions
Most DNA methylation differences between primary CRCs and matched liver metastasis are due to random variation and an increase in DNA methylation density rather than de-novo inactivation and silencing. Thus, DNA methylation changes occur for the most part before progression to liver metastasis. 相似文献204.
In typical sexual conflict scenarios, males best equipped to exploit females are favored locally over more prudent males, despite reducing female fitness. However, local advantage is not the only relevant form of selection. In multigroup populations, groups with less sexual conflict will contribute more offspring to the next generation than higher conflict groups, countering the local advantage of harmful males. Here, we varied male aggression within- and between-groups in a laboratory population of water striders and measured resulting differences in local population growth over a period of three weeks. The overall pool fitness (i.e., adults produced) of less aggressive pools exceeded that of high aggression pools by a factor of three, with the high aggression pools essentially experiencing no population growth over the course of the study. When comparing the fitness of individuals across groups, aggression appeared to be under stabilizing selection in the multigroup population. The use of contextual analysis revealed that overall stabilizing selection was a product of selection favoring aggression within groups, but selected against it at the group-level. Therefore, this report provides further evidence to show that what evolves in the total population is not merely an extension of within-group dynamics. 相似文献
205.
206.
Twenty one fungal isolates belonging to 7 genera were screened for ureolytic activity. APenicillium waksmanii isolate was found to be the most potent and was selected for further study. No ammonia-nitrogen was detected inP. waksmanii cultures either urea-free or containing up to 1 g urea per L. The maximum extracellular urease production was recorded at
a urea concentration of 15 g/L. It peaked after 6 d of incubation at 25°C when the initial pH of the glucose—peptone broth
was adjusted to 6. On the other hand, the highest fungus biomass was detected at a concentration of 2 g urea per L after 4
d of incubation at 35°C when the pH of the medium was 8. The intracellular urease activity (measured in cell-free extract)
was the highest at 12 mg urea per mL after 75-min incubation at 25°C at pH 8. Incubation temperature of 25°C favored both
urease production and activity. 相似文献
207.
Jallow Mustapha F. A. Dahab Abdelhafiz A. Albaho Mohammed S. Devi Vimala Y. Jacob Joby Al-Saeed Omar 《Applied Entomology and Zoology》2020,55(2):213-221
Applied Entomology and Zoology - The efficacy of mating disruption with Isonet®-T at the rate of 30, 45 or 60 g a.i. ha –1 of sex pheromone to control Tuta absoluta (Meyrick)... 相似文献
208.
Periklis?Makrythanasis Michel?Guipponi Federico?A.?Santoni Maha?Zaki Mahmoud?Y.?Issa Muhammad?Ansar Hanan?HamamyEmail author Stylianos?E.?AntonarakisEmail author 《Human genomics》2016,10(1):26
Background
The recent availability of whole-exome sequencing has opened new possibilities for the evaluation of individuals with genetically undiagnosed intellectual disability.Results
We report two affected siblings, offspring of first-cousin parents, with intellectual disability, hypotonia, short stature, growth hormone deficiency, and delayed bone age. All members of the nuclear family were genotyped, and exome sequencing was performed in one of the affected individuals. We used an in-house algorithm (CATCH v1.1) that combines homozygosity mapping with exome sequencing results and provides a list of candidate variants. One identified novel homozygous missense variant in KALRN (NM_003947.4:c.3644C>A: p.(Thr1215Lys)) was predicted to be pathogenic by all pathogenicity prediction software used (SIFT, PolyPhen, Mutation Taster). KALRN encodes the protein kalirin, which is a GTP-exchange factor protein with a reported role in cytoskeletal remodeling and dendritic spine formation in neurons. It is known that mice with ablation of Kalrn exhibit age-dependent functional deficits and behavioral phenotypes.Conclusion
Exome sequencing provided initial evidence linking KALRN to monogenic intellectual disability in man, and we propose that KALRN is the causative gene for the autosomal recessive phenotype in this family.209.
210.
Bakr Mohamed El-Zawahry Omar Ahmed AzzamNagla Sameh Zaki Heba Mohamed Abdel-RaheemDalia Ahmed Bassiouny Mervat Mamdooh Khorshied 《Gene》2013
PTPN22 1858C>T gene polymorphism has been associated with several autoimmune disorders including alopecia areata. The aim of the current study was to investigate the effect of the inherited genetic polymorphism 1858C>T of PTPN22 gene on the predisposition to severe forms of alopecia areata and its effect on the response to DPC treatment. To achieve our aim, PTPN22 1858C>T genotyping was performed by PCR-based restricted fragment length polymorphism (PCR-RFLP) analysis. The study included 103 Egyptian patients with extensive alopecia areata treated by DPC. Hundred healthy age and sex matched blood donors were included in the current study as a control group. Results of genotyping showed that PTPN22 CT and TT mutant genotypes were significantly higher in AA patients compared to controls and conferred increase risk of AA (OR = 2.601, 95% CI = 1.081–6.255). Statistical comparison between AA patients with wild and mutant genotypes revealed that the duration of the illness was significantly longer in those harboring the mutant genotypes. Moreover, the association of other autoimmune diseases as atopy and diabetes mellitus was higher in patients with mutant genotypes. Furthermore, PTPN22 1858C>T genetic polymorphism did not affect the patients' response to DPC immunotherapy. 相似文献