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71.
Abeer M. Mahmoud Umaima Al-Alem Firas Dabbous Mohamed M. Ali Ken Batai Ebony Shah Rick A. Kittles 《PloS one》2016,11(11)
Zinc is an essential dietary element that has been implicated in the pathogenesis of prostate cancer, a cancer that disproportionately affects men of African descent. Studies assessing the association of zinc intake and prostate cancer have yielded inconsistent results. Furthermore, very little is known about the relationship between zinc intake and prostate cancer among African Americans. We examined the association between self-reported zinc intake and prostate cancer in a hospital-based case-control study of African Americans. We then compared our results with previous studies by performing a meta-analysis to summarize the evidence regarding the association between zinc and prostate cancer. Newly diagnosed African American men with histologically confirmed prostate cancer (n = 127) and controls (n = 81) were recruited from an urban academic urology clinic in Washington, DC. Controls had higher zinc intake, with a mean of 14 mg/day versus 11 mg/day for cases. We observed a non-significant, non-linear increase in prostate cancer when comparing tertiles of zinc intake (OR <6.5 vs 6.5–12.5mg/day 1.8, 95% CI: 0.6,5.6; OR <6.5 vs >12.5mg/day 1.3, 95% CI: 0.2,6.5). The pooled estimate from 17 studies (including 3 cohorts, 2 nested case-control, 11 case-control studies, and 1 randomized clinical trial, with a total of 111,199 participants and 11,689 cases of prostate cancer) was 1.07hi vs lo 95% CI: 0.98–1.16. Using a dose-response meta-analysis, we observed a non-linear trend in the relationship between zinc intake and prostate cancer (p for nonlinearity = 0.0022). This is the first study to examine the relationship between zinc intake in black men and risk of prostate cancer and systematically evaluate available epidemiologic evidence about the magnitude of the relationship between zinc intake and prostate cancer. Despite of the lower intake of zinc by prostate cancer patients, our meta-analysis indicated that there is no evidence for an association between zinc intake and prostate cancer. 相似文献
72.
Improved heterologous production of the nonribosomal peptide‐polyketide siderophore yersiniabactin through metabolic engineering and induction optimization 下载免费PDF全文
Biosynthesis of complex natural products like polyketides and nonribosomal peptides using Escherichia coli as a heterologous host provides an opportunity to access these molecules. The value in doing so stems from the fact that many compounds hold some therapeutic or other beneficial property and their original production hosts are intractable for a variety of reasons. In this work, metabolic engineering and induction variable optimization were used to increase production of the polyketide‐nonribosomal peptide compound yersiniabactin, a siderophore that has been utilized to selectively remove metals from various solid and aqueous samples. Specifically, several precursor substrate support pathways were altered through gene expression and exogenous supplementation in order to boost production of the final compound. The gene expression induction process was also analyzed to identify the temperatures and inducer concentrations resulting in highest final production levels. When combined, yersiniabactin production was extended to ~175 mg L?1. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1412–1417, 2016 相似文献
73.
Here, an ultrasensitive label-free electrochemical aptasensor was developed for dopamine (DA) detection. Construction of the aptasensor was carried out by electrodeposition of gold–platinum nanoparticles (Au–PtNPs) on glassy carbon (GC) electrode modified with acid-oxidized carbon nanotubes (CNTs–COOH). A designed complementary amine-capped capture probe (ssDNA1) was immobilized at the surface of PtNPs/CNTs–COOH/GC electrode through the covalent amide bonds formed by the carboxyl groups on the nanotubes and the amino groups on the oligonucleotides. DA-specific aptamer was attached onto the electrode surface through hybridization with the ssDNA1. Methylene blue (MB) was used as an electrochemical indicator that was intercalated into the aptamer through the specific interaction with its guanine bases. In the presence of DA, the interaction between aptamer and DA displaced the MB from the electrode surface, rendering a lowered electrochemical signal attributed to a decreased amount of adsorbed MB. This phenomenon can be applied for DA detection. The peak current of probe (MB) linearly decreased over a DA concentration range of 1–30 nM with a detection limit of 0.22 nM. 相似文献
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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.77.
Spectrofluorimetric determination of thioridazine and flupentixol in dosage forms; application to content uniformity test 下载免费PDF全文
A reliable, sensitive, cheap and non‐extractive spectrofluorimetric method has been developed and validated for determination of thioridazine and flupentixol based on ternary complex formation with eosin and lead(II) in the presence of methylcellulose as surfactant at pH 3.2. Under the optimum conditions, the quantitative quenching effect of investigated drugs on the native fluorescence of eosin has been investigated. The quenching of the eosin fluorescence was measured at 517 nm after excitation at 462 nm. The different experimental parameters affecting the development and stability of the reaction products were carefully studied and optimized, and the results were satisfactory. The calibration plots were constructed over the range of 0.5–3.0 µg mL?1. The developed method was successfully applied for determination of investigated drugs in commercial tablets without interference from common excipients. It was further applied for content uniformity testing of flupentixol in its tablets. Statistical comparisons of the results with those of the reference methods revealed excellent agreement and indicated no significant difference in accuracy and precision. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
78.
László?K?lesEmail author Erzsébet?Kató Adrienn?Hanuska Zoltán?S.?Zádori Mahmoud?Al-Khrasani Tibor?Zelles Patrizia?Rubini Peter?IllesEmail author 《Purinergic signalling》2016,12(1):1-24
Glutamate is the main excitatory neurotransmitter of the central nervous system (CNS), released both from neurons and glial cells. Acting via ionotropic (NMDA, AMPA, kainate) and metabotropic glutamate receptors, it is critically involved in essential regulatory functions. Disturbances of glutamatergic neurotransmission can be detected in cognitive and neurodegenerative disorders. This paper summarizes the present knowledge on the modulation of glutamate-mediated responses in the CNS. Emphasis will be put on NMDA receptor channels, which are essential executive and integrative elements of the glutamatergic system. This receptor is crucial for proper functioning of neuronal circuits; its hypofunction or overactivation can result in neuronal disturbances and neurotoxicity. Somewhat surprisingly, NMDA receptors are not widely targeted by pharmacotherapy in clinics; their robust activation or inhibition seems to be desirable only in exceptional cases. However, their fine-tuning might provide a promising manipulation to optimize the activity of the glutamatergic system and to restore proper CNS function. This orchestration utilizes several neuromodulators. Besides the classical ones such as dopamine, novel candidates emerged in the last two decades. The purinergic system is a promising possibility to optimize the activity of the glutamatergic system. It exerts not only direct and indirect influences on NMDA receptors but, by modulating glutamatergic transmission, also plays an important role in glia-neuron communication. These purinergic functions will be illustrated mostly by depicting the modulatory role of the purinergic system on glutamatergic transmission in the prefrontal cortex, a CNS area important for attention, memory and learning. 相似文献
79.
Ziad A Audat Mahmoud H. Hajyousef Mohammad D. Fawareh Khaldoon M. Alawneh Mohannad A. Odat Mohammad M. Barbarawi Ali A. Alomari Rami A. Jahmani Mohammad A. Khatatbeh Mohammed A. Assmairan 《Scoliosis》2016,11(1):47
Background
This was a prospective study to evaluate the effect of multilevel vertebral augmentation in addition to conventional therapy in multiple myeloma patients.Methods
We treated 27 patients, whom were recently diagnosed to have multiple myeloma by two ways of treatment. Thirteen patients (group I) were treated with conventional therapy and 14 patients (group II) with adding vertebroplasty and kyphoplasty. Patients were evaluated pre-treatment and at half, one, two and 3-years post-treatment by using Oswestry Disability Index (ODI), the Stanford Score (SS) and the Spinal Instability Neoplastic Score (SINS).Results
Mean values of ODI, SS and SINS were 31.9 (63.8%), 4.3 and 13.8 for group I and 33.2 (66.4%), 4.6 and 12.8 for group II before starting treatment. Group II showed improvement better than group I at all follow-up intervals with best results at first 6 months. P-values at the end of the study were ODI?=?0.047, SS?=?0.180 and SINS?=?0.002. Mortality rates were equal of both groups (four patients of each group).Conclusion
Adding vertebral augmentation to conventional therapy improves multiple myeloma patients’ quality of life, but didn’t affect the mortality rate.80.