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31.
Fang Hua Jun Wang Iqbal Sayeed Tauheed Ishrat Fahim Atif Donald G. Stein 《Biochemical and biophysical research communications》2009,390(3):678-1466
TIR domain-containing adaptor protein (TRIF) is an adaptor protein in Toll-like receptor (TLR) signaling pathways. Activation of TRIF leads to the activation of interferon regulatory factor 3 (IRF3) and nuclear factor kappa B (NF-κB). While studies have shown that TLRs are implicated in cerebral ischemia/reperfusion (I/R) injury and in neuroprotection against ischemia afforded by preconditioning, little is known about TRIF’s role in the pathological process following cerebral I/R. The present study investigated the role that TRIF may play in acute cerebral I/R injury. In a mouse model of cerebral I/R induced by transient middle cerebral artery occlusion, we examined the activation of NF-κB and IRF3 signaling in ischemic cerebral tissue using ELISA and Western blots. Neurological function and cerebral infarct size were also evaluated 24 h after cerebral I/R. NF-κB activity and phosphorylation of the inhibitor of kappa B (IκBα) increased in ischemic brains, but IRF3, inhibitor of κB kinase complex-ε (IKKε), and TANK-binding kinase1 (TBK1) were not activated after cerebral I/R in wild-type (WT) mice. Interestingly, TRIF deficit did not inhibit NF-κB activity or p-IκBα induced by cerebral I/R. Moreover, although cerebral I/R induced neurological and functional impairments and brain infarction in WT mice, the deficits were not improved and brain infarct size was not reduced in TRIF knockout mice compared to WT mice. Our results demonstrate that the TRIF-dependent signaling pathway is not required for the activation of NF-κB signaling and brain injury after acute cerebral I/R. 相似文献
32.
Arbuscular Mycorrhizal Fungi Enhance Zinc and Nickel Uptake from Contaminated Soil by Soybean and Lentil 总被引:1,自引:0,他引:1
Atif Jamal Najma Ayub Muhammad Usman Dr. Abdul G. Khan 《International journal of phytoremediation》2002,4(3):205-221
Generally, soils in Pakistan are deficient in P and N. Due to intensive cropping and irrigation, Pakistani soils have also become deficient in micronutrients such as Zn, Fe, Cu, and Mn. Arbuscular mycorrhizal fungi, which form symbiotic associations with roots of most land plants, are known to enhance uptake of P and trace elements such as Cu, Ni, Pb, and Zn. The present study was conducted to investigate the role of arbuscular mycorrhizae (AM) in uptake of nickel (Ni) and zinc (Zn) by crops viz. soybean (Glycine max (L.) Merrill) and lentil (Lens culinaris Medic). Zn and Ni were applied as ZnSO4 7H2O and NiCl2 respectively, in four concentrations (0.0, 1.0, 3.0, and 5.0 g kg-1 soil). AM inoculum consisted of sand containing sporocarps, spores, and AMF infected root pieces from a pot culture of Glomus mosseae. Control plants received pot culture filtrate containing soil microflora minus AM fungal propagules. A significant difference (p < 0.05) was observed in the dry weights of roots and shoots of the mycorrhizal (M) and nonmycorrhizal (NM) cereal plants. The sievate-amended treatments did not stimulate plant growth to the same extent as the AM fungal amended treatments. Trace metals inhibited the extent of mycorrhizal colonization of the cereal roots. The concentrations of the trace metals in the plant tissues of 12-week old cereal plants were found significantly (p < 0.05) higher in M than NM plants. These results indicate that mycorrhize can be used as effective tools to supply sufficient Zn in generally Zn-deficient Pakistani soils and to ameliorate the toxicity of trace metals in polluted soils. The contents of Ni in mycorrhizal soybean plant tissues were higher than those in the mycorrhizal lentil plant tissues. The implications of these results in mycorrhizo remediation of agricultural soils are discussed. 相似文献
33.
Protein proteinase inhibitor genes in combat against insects, pests, and pathogens: natural and engineered phytoprotection 总被引:11,自引:0,他引:11
The continual need to increase food production necessitates the development and application of novel biotechnologies to enable the provision of improved crop varieties in a timely and cost-effective way. A milestone in this field was the introduction of Bacillus thuringiensis (Bt) entomotoxic proteins into plants. Despite the success of this technology, there is need for development of alternative strategies of phytoprotection. Biotechnology offers sustainable solutions to the problem of pests, pathogens, and plant parasitic nematodes in the form of other insecticidal protein genes. A variety of genes, besides (Bt) toxins that are now available for genetic engineering for pest resistance are genes for vegetative insecticidal proteins, proteinase inhibitors, alpha-amylase inhibitors, and plant lectins. This review presents a comprehensive summary of research efforts that focus on the potential use and advantages of using proteinase inhibitor genes to engineer insect- and pest-resistance. Crop protection by means of PI genes is an important component of Integrated Pest Management programmes. 相似文献
34.
Charlwood J Skehel JM King N Camilleri P Lord P Bugelski P Atif U 《Journal of proteome research》2002,1(1):73-82
The regionally specific structure and function of the kidney renders it susceptible to toxic exposure. To characterize these changes at the proteome level, we have investigated the effects on protein expression following treatment with gentamicin. The more than 20 proteins identified were involved in the citric acid cycle, gluconeogenesis, fatty acid synthesis, and transport or cellular stress responses. These results strongly support the notion that energy production is impaired and mitochondrial dysfunction is involved in gentamicin-induced nephrotoxicity. 相似文献
35.
Alaa Fehaid Mohammad S. Al-Ghamdi Khalid J. Alzahrani Abdulrahman Theyab Osama M. Al-Amer Saad S. Al-Shehri Mohammad Algahtani Atif Abdulwahab A. Oyouni Mrim M. Alnfiai Mohamed H. Aly Khalaf F. Alsharif Ashraf Albrakati Rami B. Kassab Hussam A. Althagafi Fahad Alharthi Ahmed E. Abdel Moneim Maha S. Lokman 《Journal of biochemical and molecular toxicology》2023,37(3):e23275
Exposure to lead (Pb) is associated with serious health problems including hepatorenal toxicity. Apigenin is a natural-sourced flavonoid with promising antioxidant and anti-inflammatory effects. In this research, we investigated the potential protective role of apigenin against lead acetate (PbAc)-induced hepatorenal damage. Thus, this experiment studied the exposure of male Wistar Albino rats to apigenin and/or PbAc and their effects in comparison to the control rats. Apigenin administration decreased the levels of Pb and prevented the histopathological deformations in liver and kidney tissues following PbAc exposure. This was confirmed by the normalized levels of liver and kidney function markers. Additionally, apigenin inhibited significantly oxidative reactions through upregulating Nrf2 and HO-1, and activating their downstreamed antioxidants accompanied by a marked depletion of pro-oxidants. Moreover, apigenin decreased the elevated pro-inflammatory cytokines and inhibited cell loss in liver and kidney tissues in response to PbAc intoxication in both tissues. The obtained results demonstrated that apigenin could be used to attenuate the molecular, biochemical, and histological alterations associated with Pb exposure due to its potent antioxidant, anti-inflammatory, and antiapoptotic effects. 相似文献
36.
The fatty acyl group composition of Ehrlich ascites tumor cell plasma membranes was modified by feeding the tumor-bearing mice diets rich in either coconut or sunflower oil. When coconut oil was fed, the oleate content of the membrane phospholipids was elevated and the linoleate content reduced. The opposite occurred when sunflower oil was fed. Qualitatively similar changes were observed in the plasma membrane phosphatidylethanolamine, phosphatidylcholine and mixed phosphatidylserine plus phosphatidylinositol fractions. These diets also produced differences in the sphingomyelin fraction, particularly in the palmitic and nervonic acid contents. Unexpectedly, the saturated fatty acid content of the plasma membrane phospholipids was somewhat greater when the highly polyunsaturated sunflower oil was fed. The small quantities of neutral lipids contained in the plasma membrane exhibited changes in acyl group composition similar to those observed in the phospholipids. These fatty acyl group changes were not accompanied by any alteration in the cholesterol or phospholipid contents of the plasma membranes. Therefore, the lipid alterations produced in this experimental model system are confined to the membrane acyl groups. 相似文献
37.
Amphiphilic 2,17-bis-sulfonato-5,10,15(trispentafluorophenyl)corrole (2) and its Ga and Mn complexes (2-Ga and 2-Mn) form tightly bound noncovalent conjugates with human serum albumin (HSA). Protein-induced changes in the electronic absorption, emission, and circular dichroism spectra of these corroles, as well as results obtained from HPLC profiles of the conjugates and selective fluorescence quenching of the single HSA tryptophan, are interpreted in terms of multiple corrole:HSA binding sites. High-affinity binding sites, close to the unique tryptophan, are fully occupied at very low concentrations. At biologically relevant HSA concentrations (2-3 orders of magnitude larger than those employed in our studies), all corroles (2, 2-Ga, and 2-Mn) may be considered as fully conjugated. 相似文献
38.
Weinstock-Guttman B Baier M Park Y Feichter J Lee-Kwen P Gallagher E Venkatraman J Meksawan K Deinehert S Pendergast D Awad AB Ramanathan M Munschauer F Rudick R 《Prostaglandins, leukotrienes, and essential fatty acids》2005,73(5):397-404
OBJECTIVES: To determine whether a low fat diet supplemented with omega-3 positively affects quality of life (QOL) in relapsing-remitting MS (RRMS) patients. In this 1-year long double-blind, randomized trial, patients were randomized to two dietary interventions: the "Fish Oil" (FO) group received a low fat diet (15% fat) with omega-3 FOs and the "Olive Oil" (OO) group received the AHA Step I diet (fat 30%) with OO supplements. The primary outcome measure was the Physical Components Summary Scale (PCS) of the Short Health Status Questionnaire (SF-36). Additional measures using MS specific QOL questionnaires, neurological status and relapse rate were obtained. RESULTS: 31 RRMS patients were enrolled, with mean follow up over 11 +/- SD 2.9 months. Clinical benefits favoring the FO group were observed on PCS/SF-36 (P = 0.050) and MHI (P = 0.050) at 6 months. Reduced fatigue was seen on the OO diet at 6 months (P = 0.035). The relapse rate decreased in both groups relative to the rates during the 1 year preceding the study: mean change in relapse rate in the FO group: -0.79 +/- SD 1.12 relapses/year (P = 0.021) vs. -0.69 +/- SD 1.11 (P = 0.044) in the OO group. This study suggests that a low fat diet supplemented with omega-3 PUFA can have moderate benefits in RRMS patients on concurrent disease modifying therapies. 相似文献
39.
Humblet V Lapidus R Williams LR Tsukamoto T Rojas C Majer P Hin B Ohnishi S De Grand AM Zaheer A Renze JT Nakayama A Slusher BS Frangioni JV 《Molecular imaging》2005,4(4):448-462
Surgical resection remains a definitive treatment for prostate cancer. Yet, prostate cancer surgery is performed without image guidance for tumor margin, extension beyond the capsule and lymph node positivity, and without verification of other occult metastases in the surgical field. Recently, several imaging systems have been described that exploit near-infrared (NIR) fluorescent light for sensitive, real-time detection of disease pathology intraoperatively. In this study, we describe a high-affinity (9 nM), single nucleophile-containing, small molecule specific for the active site of the enzyme PSMA. We demonstrate production of a tetra-sulfonated heptamethine indocyanine NIR fluorescent derivative of this molecule using a high-yield LC/MS purification strategy. Interestingly, NIR fluorophore conjugation improves affinity over 20-fold, and we provide mechanistic insight into this observation. We describe the preparative production of enzymatically active PSMA using a baculovirus expression system and an adenovirus that co-expresses PSMA and GFP. We demonstrate sensitive and specific in vitro imaging of endogenous and ectopically expressed PSMA in human cells and in vivo imaging of xenograft tumors. We also discuss chemical strategies for improving performance even further. Taken together, this study describes nearly complete preclinical development of an optically based small-molecule contrast agent for image-guided surgery. 相似文献
40.
Adhip P. Nandi Majumdar Atif M. Nakhla 《Biochemical and biophysical research communications》1977,76(1):71-77
Eight hours after a single tube-feeding of tryptophan the activity of acetylcholinesterase in the cerebral hemisphere of well-fed (non-fasted) normal and adrenalectomized rats was 28 and 53% higher, respectively, compared to the corresponding water-fed control. On the other hand, the enzyme activity in the cerebellum of both normal and adrenalectomized rats remained essentially unchanged following tryptophan administration. Pretreatment of adrenalectomized rats with actinomycin-D totally abolished the tryptophan-mediated stimulation of cerebral acetylcholinesterase activity. The pattern of response of cerebral acetylcholinesterase in well-fed adrenalectomized rats over a period of 24-hr following a dose of tryptophan was found to be biphasic. 相似文献