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131.
132.
Ahmed Al-Qahtani Mashael Al-Anazi Nisha A. Viswan Nisreen Khalaf Ayman A. Abdo Faisal M. Sanai Hamad Al-Ashgar Mohammed Al-Ahdal 《PloS one》2012,7(9)
Background/Aim
Kinesin family member 1B (KIF1B) gene resides in the chromosomal region 1p36.22 and has been reported to have frequent deletions in a variety of human cancers. A recent genome wide association study (GWAS) study conducted on a Chinese population has reported the involvement of a KIF1B genetic variant in Hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). This study aims to investigate the significance of KIF1B genetic variations in HBV-associated hepatitis in patients of Saudi Arabian ethnicity.Methods
TaqMan genotyping assay was used to investigate the association of three SNPs (rs17401966, rs12734551, and rs3748578) in 584 normal healthy controls and 660 HBV-infected patients. The patients were categorized into inactive carriers (Case I), active carriers (Case II), Cirrhosis (Case III) and Cirrhosis-HCC (Case IV) sub-groups.Results
Since SNPs rs12734551 and rs3748578 are in strong linkage disequilibrium (LD) with rs17401966, only results for the latter SNP are reported. Therefore, the allele frequency of rs17401966 among HBV-infected patients and healthy controls were comparable and therefore, no significant association was observed (P = 0.2811, Odds Ratio (OR) 0.897). A similar analysis was performed among the different sub-groups in order to determine whether KIF1B SNPs were associated with the advancement of the disease. No significant differences were observed in any of the comparisons performed.Conclusion
Polymorphisms at KIF1B gene locus investigated in this study showed no significant association with HBV infection or with HBV-associated diseases such as liver cirrhosis or HCC. 相似文献133.
Wu L Al-Hejazi A Filion L Ben R Halpenny M Yang L Giulivi A Allan DS 《Cytotherapy》2012,14(2):205-214
Background aimsDelayed neutrophil recovery following autologous hematopoietic stem cell transplantation (aHSCT) increases transplant-related morbidity. Apoptosis induced by cryopreservation and thawing of hematopoietic progenitor cells collected by apheresis (HPC-A) was investigated in this nested case-control study as a factor associated with delayed neutrophil recovery following aHSCT.MethodsAmong patients with lymphoma who underwent aHSCT between 2000 and 2007 (n = 326), 13 cases of primary delayed neutrophil recovery and 22 age- and sex-matched controls were identified. Apoptosis and viability were measured using multiparameter flow cytometry, and colony-forming capacity was determined using semi-solid methylcellulose assays.ResultsHPC-A grafts from cases and controls had similar percentages of viable mononuclear cells (MNC) and CD34+progenitor cells, as determined by standard 7AAD dye exclusion methods measured before and after cryopreservation. Patients with delayed neutrophil recovery received increased numbers of apoptotic MNC (P = 0.02) but similar numbers of apoptotic CD34+ cells per kilogram measured after thawing. Apoptosis was more pronounced in MNC compared with CD34+ cells after thawing, and apoptosis was negligible in freshly collected HPC-A products. Patients with delayed neutrophil recovery had fewer total colony-forming unites (CFU) and CFU-granulocyte–macrophages (GM) per 105 viable post-thaw MNC compared with controls (P < 0.05).ConclusionsIncreased numbers of apoptotic MNC in thawed HPC-A products are associated with delayed neutrophil recovery after aHSCT. Studies that address factors contributing to increased apoptosis are needed, and measuring apoptosis in thawed HPC-A may have a role in the assessment of graft adequacy. 相似文献
134.
135.
Raboin SJ Gulley S Henley SC Chan WC Esdaile AR Jackson CA Billups LH Sayegh AI 《Regulatory peptides》2006,134(2-3):141-148
Chemical sympathectomy with daily, intraperitoneal (IP) injections of guanethidine sulfate to adult rats, attenuated myenteric, but not dorsal vagal complex (DVC) Fos-like immunoreactivity (Fos-LI) by cholecystokinin-8 (CCK). This technique destroys only 60-70% of the sympathetic neurons, and spares the hormonal source of catecholamines, the adrenal medulla. The goal of the current study is to evaluate the effect of complete sympathectomy or destroying 100% of the sympathetic neurons by injecting guanethidine to 1-day-old pups (40 mg/kg daily for 5 weeks), and surgically removing the adrenal medulla. In the DVC, demedullation and sympathectomy-demedullation increased Fos-LI by CCK in the area postrema and nucleus of the solitary tract, but sympathectomy-demedullation increased it only in the area postrema. In the myenteric plexus, sympathectomy increased this response in the duodenum, and demedullation increased it in the duodenum and jejunum. On the other hand, sympathectomy-demedullation attenuated myenteric Fos-LI in the jejunum. These results indicate that catecholamines may play an inhibitory role on the activation of the DVC neurons by CCK. In the myenteric neurons, however, catecholamines may have both inhibitory and excitatory roles depending on the level of the intestine e.g., duodenum vs. jejunum. This may also indicate that CCK activates the enteric neurons by different mechanisms or through different pathways. 相似文献
136.
Sherine Nabil Khattab Nesreen Saied Haiba Ahmed Mosaad Asal Adnan A. Bekhit Aida A. Guemei Adel Amer Ayman El-Faham 《Bioorganic & medicinal chemistry letters》2017,27(4):918-921
A new small library of 2-aminobenzoyl amino acid hydrazide derivatives and quinazolinones derivatives was synthesized and fully characterized by IR, NMR, and elemental analysis. The activity of the prepared compounds on the growth of Leishmania aethiopica promastigotes was evaluated. 2-Benzoyl amino acid hydrazide showed higher inhibitory effect than the quinazoline counterpart. The in vitro antipromastigote activity demonstrated that compounds 2a, 2b, 2f and 4a had IC50 better than standard drug miltefosine and comparable activity to amphotericin B deoxycholate, which indicates their high antileishmanial activity against Leishmania. aethiopica. Among the prepared compounds; 2-amino-N-(6-hydrazinyl-6-oxohexyl)benzamide 2f (IC50 = 0.051 μM) has the best activity, 154 folds more active than reference standard drug miltefosine (IC50 = 7.832 μM), and half fold the activity of amphotericin B (IC50 = 0.035 μM). In addition, this compound was safe and well tolerated by experimental animals orally up to 250 mg/kg and parenterally up to 100 mg/kg. 相似文献
137.
Ayman El-Faham Abdel Moneim El Massry Adel Amer Yousry M. Gohar 《Letters in Peptide Science》2002,9(1):49-54
The synthesis of N-protected L-amino acid (3-benzylquinoxalin-2-yl) hydrazide derivatives is reported here. 3-Benzyl-2-hydrazinoquinoxaline was prepared and then coupled with N-Boc-L-amino acids including; Alanine, Valine, Leucine, Phenylalanine, Tyrosine, Serine and Proline in the presence of HBTU as a coupling reagent to provide the expected product with high yield and purity. The products were deprotected by p-toluenesulphonic acid in acetonitrile and then the tosylate salts were evaluated for antibacterial and antifungal activity. 相似文献
138.
Estate Sokhadze Joshua Baruth Allan Tasman Lonnie Sears Grace Mathai Ayman El-Baz Manuel F. Casanova 《Applied psychophysiology and biofeedback》2009,34(1):37-51
To better understand visual processing abnormalities in autism we studied the attention orienting related frontal event potentials
(ERP) and the sustained attention related centro-parietal ERPs in a three stimulus oddball experiment. The three stimulus
oddball paradigm was aimed to test the hypothesis that individuals with autism abnormally orient their attention to novel
distracters as compared to controls. A dense-array 128 channel EGI electroencephalographic (EEG) system was used on 11 high-functioning
children and young adults with autism spectrum disorder (ASD) and 11 age-matched, typically developing control subjects. Patients
with ASD showed slower reaction times but did not differ in response accuracy. At the anterior (frontal) topography the ASD
group showed significantly higher amplitudes and longer latencies of early ERP components (e.g., P100, N100) to novel distracter
stimuli in both hemispheres. The ASD group also showed prolonged latencies of late ERP components (e.g., P2a, N200, P3a) to
novel distracter stimuli in both hemispheres. However, differences were more profound in the right hemisphere for both early
and late ERP components. Our results indicate augmented and prolonged early frontal potentials and a delayed P3a component
to novel stimuli, which suggest low selectivity in pre-processing and later-stage under-activation of integrative regions
in the prefrontal cortices. Also, at the posterior (centro-parietal) topography the ASD group showed significantly prolonged
N100 latencies and reduced amplitudes of the N2b component to target stimuli. In addition, the latency of the P3b component
was prolonged to novel distracters in the ASD group. In general, the autistic group showed prolonged latencies to novel stimuli
especially in the right hemisphere. These results suggest that individuals with autism over-process information needed for
the successful differentiation of target and novel stimuli. We propose the potential application of ERP evaluations in a novelty
task as outcome measurements in the biobehavioral treatment (e.g., EEG biofeedback, TMS) of autism. 相似文献
139.
Ayman G Mustafa Mohammad A Bani-Ahmad Ahmad Q Jaradat Mohammed Z Allouh 《Experimental biology and medicine (Maywood, N.J.)》2015,240(1):109-112
Oxidative stress is characterized by excessive production of various free radicals and reactive species among which, peroxynitrite is most frequently produced in several pathological conditions. Peroxynitrite is the product of the superoxide anion reaction with nitric oxide, which is reported to take place in the intravascular compartment. Several studies have reported that peroxynitrite targets red blood cells, platelets and plasma proteins, and induces various forms of oxidative damage. This in vitro study was designed to further characterize the types of oxidative damage induced in platelets and plasma proteins by peroxynitrite. This study also determined the ability of tempol to protect blood plasma and platelets against peroxynitrite-induced oxidative damage. The ability of various concentrations of tempol (25, 50, 75, and 100 µM) to antagonize peroxynitrite-induced oxidation was evaluated by measuring the levels of protein carbonyl groups and thiobarbituric-acid-reactive substances in experimental groups. Exposure of platelets and plasma to 100 µM peroxynitrite resulted in an increased levels of carbonyl groups and lipid peroxidation (P < 0.05). Tempol significantly inhibited carbonyl group formation in plasma and platelet proteins (P < 0.05). In addition, tempol significantly reduced the levels of lipid peroxidation in both plasma and platelet samples (P < 0.05). Thus, tempol has antioxidative properties against peroxynitrite-induced oxidative damage in blood plasma and platelets. 相似文献
140.
Sabrina Llop Karin Engstr?m Ferran Ballester Elisa Franforte Ayman Alhamdow Federica Pisa Janja Snoj Tratnik Datja Mazej Mario Murcia Marisa Rebagliato Mariona Bustamante Jordi Sunyer Αikaterini Sofianou-Katsoulis Alexia Prasouli Eleni Antonopoulou Ioanna Antoniadou Sheena Nakou Fabio Barbone Milena Horvat Karin Broberg 《PloS one》2014,9(5)