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Benjamin Drew Rockett Mark Melton Mitchel Harris Lance C. Bridges Saame Raza Shaikh 《The Journal of nutritional biochemistry》2013,24(11):1810-1816
Fish oil-enriched long chain n-3 polyunsaturated fatty acids disrupt the molecular organization of T-cell proteins in the immunological synapse. The impact of fish oil derived n-3 fatty acids on antigen-presenting cells, particularly at the animal level, is unknown. We previously demonstrated B-cells isolated from mice fed with fish oil-suppressed naïve CD4+ T-cell activation. Therefore, here we determined the mechanistic effects of fish oil on murine B-cell major histocompatibility complex (MHC) class II molecular distribution using a combination of total internal reflection fluorescence, Förster resonance energy transfer and confocal imaging. Fish oil had no impact on presynaptic B-cell MHC II clustering. Upon conjugation with transgenic T-cells, fish-oil suppressed MHC II accumulation at the immunological synapse. As a consequence, T-cell protein kinase C theta (PKCθ) recruitment to the synapse was also diminished. The effects were independent of changes in B-T cell adhesion, as measured with microscopy, flow cytometry and static cell adhesion assays with select immune ligands. Given that fish oil can reorganize the membrane by lowering membrane cholesterol levels, we then compared the results with fish oil to cholesterol depletion using methyl-B-cyclodextrin (MβCD). MβCD treatment of B-cells suppressed MHC II and T-cell PKCθ recruitment to the immunological synapse, similar to fish oil. Overall, the results reveal commonality in the mechanism by which fish oil manipulates protein lateral organization of B-cells compared to T-cells. Furthermore, the data establish MHC class II lateral organization on the B-cell side of the immunological synapse as a novel molecular target of fish oil. 相似文献
24.
Jamil?Ahmed?SoomroEmail author Zeeshan?Noor?Shaikh Tennegedara?Buhary?Saheer Suhail?Ahmed?Bijarani 《International breastfeeding journal》2016,11(1):24
Background
Breastfeeding is considered to be an important measure to achieve optimum health outcomes for children, women’s return to work has frequently been found to be a main contributor to the early discontinuation of breastfeeding. The aim of the study is to assess workplace breastfeeding support provided to working mothers in Pakistan.Method
A workplace based cross-sectional survey was conducted from April through December 2014. Employers from a representative sample of 297 workplaces were interviewed on pre-tested and structured questionnaire. The response rate was 93.7 %. Prevalence of workplace breastfeeding facilities were assessed in the light of World Alliance for Breastfeeding Action (WABA) guidelines.Results
Among non-physical facilities, all workplaces offered 3 months paid maternity leave, 45 % of the sites were offering task adjustment to mothers during lactation period. Only 15 % of the sites were offering breastfeeding breaks to working mothers. Physical facilities that include a breastfeeding corner, refrigerator for storing breast milk, breast milk pump and nursery for childcare were provided in less than 7 % of the sites. Multinational organizations provided better support compared to national organizations.Conclusion
Support for continuation of breastfeeding by working women at workplaces is inadequate; hence, women discontinue breastfeeding earlier than planned. Policies need to be developed and enforced, employers and employees need to be educated and supportive environment needs to be created to encourage and facilitate breastfeeding friendly worksite environment.25.
Jamal S.M. Sabir Abdelfatteh El Omri Noor A. Shaik Babajan Banaganapalli Nahid H. Hajrah Houda Zrelli Leila Arfaoui Zuhier A. Awan Abdulkader M. Shaikh Omar Arif Mohammed Mona G. Alharbi Alawiah M. Alhebshi Robert K. Jansen Muhummadh Khan 《Saudi Journal of Biological Sciences》2019,26(7):1338-1343
Obesity is a multifactorial metabolic disorder characterized by low grade chronic inflammation. Rare and novel mutations in genes which are vital in several key pathways have been reported to alter the energy expenditure which regulates body weight. The TP53 or p53 gene plays a prominent role in regulating various metabolic activities such as glycolysis, lipolysis, and glycogen synthesis. Recent genome-wide association studies reported that tumor suppressor gene p53 variants play a critical role in the predisposition of type 2 diabetes and obesity. Till date, no reports are available from the Arabian population; hence the present study was intended to assess the association between p53 variants with risk of obesity development in the Saudi population. We have selected three p53 polymorphisms, rs1642785 (C > G), and rs9894946 (A > G), and rs1042522 (Pro72Arg; C > G) and assessed their association with obesity risk in the Saudi population. Phenotypic and biochemical parameters were also evaluated to check their association with p53 genotypes and obesity. Genotyping was carried out on 136 obese and 122 normal samples. We observed that there is significantly increased prevalence p52 Pro72Arg (rs1042522) polymorphism in obese persons when compared to controls at GG genotype in overall comparison (OR: 2.169, 95% CI: 1.086-4.334, p = 0.02716). Male obese subjects showed three-fold higher risk at GG genotype (OR: 3.275, 95% CI: 1.230-8.716, p = 0.01560) and two-fold risk at G allele (OR: 1.827, 95% CI: 1.128-2.958, p = 0.01388) of p53 variant Pro72Arg respectively. This variant has also shown significant influence on cholesterol, LDL level, and random insulin levels in obese subjects (p ≤ 0.05). In conclusion, p53 Pro72Arg variant is highly prevalent among obese individuals and may act as a genetic modifier for obesity development among Saudis. 相似文献
26.
3D-QSAR studies of Dipeptidyl peptidase IV inhibitors using a docking based alignment 总被引:1,自引:0,他引:1
Dipeptidyl peptidase IV (DPP-IV) deactivates the incretin hormones GLP-1 and GIP by cleaving the penultimate proline or alanine
from the N-terminal (P1-position) of the peptide. Inhibition of this enzyme will prevent the degradation of the incretin hormones
and maintain glucose homeostasis; this makes it an attractive target for the development of drugs for diabetes. This paper
reports 3D-QSAR analysis of several DPP-IV inhibitors, which were aligned by the receptor-based technique. The conformation
of the molecules in the active site was obtained through docking methods. The QSAR models were generated on two training sets
composed of 74 and 25 molecules which included phenylalanine, thiazolidine, and fluorinated pyrrolidine analogs. The 3D-QSAR
models are robust with statistically significant r2, q2, and values. The CoMFA and CoMSIA models were used to design some new inhibitors with several fold higher binding affinity.
Figure The CoMFA contours around molecule D1T155 (a) steric contours - favored (green); disfavored (yellow) (b) electrostatic contours
- electropositive (blue); electronegative (red) 相似文献
27.
Antony R. Shoaf Ali U. Shaikh Joseph H. Ford William C. Carlson Richard H. Steele 《Luminescence》1996,11(1):9-22
The reactions between superoxide free radical anion (.O−2) with the halocarbons CCl4, CHCl3, BrCH2CH2Br(EDB), decachloro-biphenyl (DCBP), and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in dimethyl sulphoxide (DMSO) results in the emission of chemiluminescence (CL). The chemiluminescence reactions are characterized as having biphasic second order kinetics, CL wavelengths between 350 nm and 650 nm, and exhibiting perturbation by chemicals reactive with singlet oxygen. These data suggest that singlet oxygen species are the excited state responsible for the light emissions. Polarographic studies confirm .O−2 consumption and halide release in the reactions, while gas liquid chromatography and NBT reduction demonstrate the decomposition of the halocarbons into products. A chemiluminescent reaction mechanism is proposed involving reductive dehalogenation of the halocarbons and the generation of singlet oxygen. The significance of singlet oxygen generation is discussed with respect to a general mechanism for explaining the rapid initiation of lipid peroxidative membrane damage in halocarbon toxigenicity in animal and plant tissues. 相似文献
28.
Tightly clustered 11q23 and 22q11 breakpoints permit PCR-based detection of the recurrent constitutional t(11;22) 下载免费PDF全文
Kurahashi H Shaikh TH Zackai EH Celle L Driscoll DA Budarf ML Emanuel BS 《American journal of human genetics》2000,67(3):763-768
Palindromic AT-rich repeats (PATRRs) on chromosomes 11q23 and 22q11 at the constitutional t(11;22) breakpoint are predicted to induce genomic instability, which mediates the translocation. A PCR-based translocation-detection system for the t(11;22) has been developed with PCR primers flanking the PATRRs of both chromosomes, to examine the involvement of the PATRRs in the recurrent rearrangement. Forty unrelated carriers of the t(11;22) balanced translocation, plus two additional, independent cases with the supernumerary-der(22) syndrome, were analyzed to compare their translocation breakpoints. Similar translocation-specific junction fragments were obtained from both derivative chromosomes in all 40 carriers of the t(11;22) balanced translocation and from the der(22) in both of the offspring with unbalanced supernumerary-der(22) syndrome, suggesting that the breakpoints in all cases localize within these PATRRs and that the translocation is generated by a similar mechanism. This PCR strategy provides a convenient technique for rapid diagnosis of the translocation, indicating its utility for prenatal and preimplantation diagnosis in families including carriers of the balanced translocation. 相似文献
29.
Sajal Chakraborti Animesh Chowdhury Pulak Kar Partha Das Soni Shaikh Soumitra Roy Tapati Chakraborti 《Archives of biochemistry and biophysics》2009,487(2):123-130
Treatment of bovine pulmonary smooth muscle cells with the TxA2 mimetic, U46619 stimulated [Ca2+]i, which was inhibited upon pretreatment with apocynin (NADPH oxidase inhibitor). Pretreatment with cromakalim (KV channel opener) or nifedepine (L-VOCC inhibitor) inhibited U46619 induced increase in [Ca2+]i, indicating a role of KV-LVOCC axis in this scenario. Neither cromakalim nor nifedepine inhibited U46619 induced increase in NADPH oxidase activity, suggesting that the NADPH oxidase activation is proximal to the KV-LVOCC axis in the cells. Pretreatment with calphostin C (PKC inhibitor) markedly reduced U46619 induced increase in NADPH oxidase activity and [Ca2+]i in the cells. Calphostin C pretreatment also markedly reduced p47phox phosphorylation and translocation to the membrane and association with p22phox, a component of Cyt.b558 of NADPH oxidase in the membrane. Overall, PKC plays an important role in NADPH oxidase derived O2−-mediated regulation of KV-LVOCC axis leading to an increase in [Ca2+]i by U46619 in the cells. 相似文献
30.
Beylergil Sinem Balta Murray Jordan Noecker Angela M. Gupta Palak Kilbane Camilla McIntyre Cameron C. Shaikh Aasef G. Ghasia Fatema F. 《Journal of computational neuroscience》2021,49(3):345-356
Journal of Computational Neuroscience - Miniature yoked eye movements, fixational saccades, are critical to counteract visual fading. Fixational saccades are followed by a return saccades forming... 相似文献