Publications by authors named "Siddiqui R"

We have previously characterized the effects of 2,6-diisopropylphenyl-docosahexaenoamide (DIP-DHA) conjugates and their analogs on the proliferation and progression of breast cancer cell lines. For this study, we investigated the effects of the DIP-DHA conjugate on 2 representative T cell acute lymphoblastic leukemia (T-ALL) cell lines: CEM and Jurkat. Treatment of both cell lines with DIP-DHA resulted in significantly greater inhibition of proliferation and induction of apoptosis than that of parent compounds, 2,6-diisopropylphenol (DIP) or docosahexaenoate (DHA).

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We previously described a lipid-accumulating phenotype of estrogen receptor negative (ER(-)) breast cancer cells exemplified by the MDA-MB-231 and MDA-MB-436 cell lines. These cells had more lipid droplets, a higher uptake of oleic acid and LDL, a higher ratio of cholesteryl ester (CE) to triacylglycerol (TAG), and higher expression of acyl-CoA:cholesterol acyltransferase 1 (ACAT1) as compared to ER(+) MCF-7 breast cancer cells. LDL stimulated proliferation of ER-cells only, and proliferation was reduced by inhibition of ACAT.

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The type III secretion system among Gram-negative bacteria is known to deliver effectors into host cell to interfere with host cellular processes. The type III secretion system in Yersina, Pseudomonas and Enterohemorrhagic Escherichia coli have been well documented to be involved in the bacterial pathogenicity. The existence of type III secretion system has been demonstrated in neuropathogenic E.

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Acanthamoeba are opportunistic protozoan pathogens that can produce sight-threatening keratitis and fatal granulomatous encephalitis. The successful prognosis requires early diagnosis and differentiation of pathogenic Acanthamoeba spp. followed by aggressive treatment regimen.

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Background: Breast cancer is a collection of diseases in which molecular phenotypes can act as both indicators and mediators of therapeutic strategy. Therefore, candidate therapeutics must be assessed in the context of multiple cell lines with known molecular phenotypes. Docosahexaenoic acid (DHA) and curcumin (CCM) are dietary compounds known to antagonize breast cancer cell proliferation.

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Acanthamoeba granulomatous encephalitis generally develops as a result of haematogenous spread, but it is unclear how circulating amoebae enter the central nervous system (CNS) and cause inflammation. At present, the mechanisms which Acanthamoeba use to invade this incredibly well-protected area of the CNS and produce infection are not well understood. In this paper, we propose two key virulence factors: mannose-binding protein and extracellular serine proteases as key players in Acanthamoeba traversal of the blood-brain barrier leading to neuronal injury.

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A recent model of collective action distinguishes 2 distinct pathways: an emotional pathway whereby anger in response to injustice motivates action and an efficacy pathway where the belief that issues can be solved collectively increases the likelihood that group members take action (van Zomeren, Spears, Fischer, & Leach, 2004). Research supporting this model has, however, focused entirely on relatively normative actions such as participating in demonstrations. We argue that the relations between emotions, efficacy, and action differ for more extreme, nonnormative actions and propose (a) that nonnormative actions are often driven by a sense of low efficacy and (b) that contempt, which, unlike anger, entails psychological distancing and a lack of reconciliatory intentions, predicts nonnormative action.

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Saturated fatty acids (SFAs), significant components of both enteral/parenteral nutritional formulations (including diet), are linked to cardiovascular disease complications, such as atherosclerosis. We investigated whether oleic acid (C18:1n-9) reduces the growth inhibitory and pro-inflammatory effects of the stearic acid (C18:0) in human aortic endothelial cells (HAEC). Stearic acid induced growth inhibition at concentrations less than 50 μM, whereas higher concentrations invoked cytotoxicity.

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Infections of the central nervous system due to neuroparasites have contributed significantly to morbidity and mortality. In part, this is because of our incomplete understanding of parasite traversal of the blood-brain barrier, a key step in the development of central nervous system infections, and the lack of available drugs that can cross the blood-brain barrier to gain entry into the brain to kill parasites. The novel in vitro, ex vivo, and in vivo models of the blood-brain barrier can offer strategies to elucidate the physical barriers, cellular mechanisms and molecular elements participating from both sides of parasite-host interactions leading to neuropathogenesis.

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The BCR-ABL1 fusion gene results from a reciprocal translocation rearrangement, t(9;22)(q34;q11.2), and is a hallmark of chronic myeloid leukemia (CML). The breakpoint on chromosome 9 is mostly 5' to ABL1 exon 2, whereas on chromosome 22, the breakpoint can occur in various regions involving the major breakpoint cluster region (M-bcr) in CML and the minor breakpoint cluster region (m-bcr) in acute lymphoblastic leukemia.

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An international project was conducted to identify the common acute lymphoblastic leukemia (ALL)-specific fusion genes (ETV6-RUNX1,MLL-AF4,TCF3-PBX1, and BCR-ABL1) in developing countries to provide additional prognostic information at diagnosis. A total of 181 children with newly diagnosed ALL were tested by reverse transcriptase-polymerase chain reaction at laboratories in India, Pakistan, Myanmar, and Sudan, following a common protocol. To our knowledge, this report is novel in its report from these countries, except India.

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The role of sphingosine 1-phosphate (S1P)-induced Rho kinase (ROCK) activation in the angiogenic responses of pulmonary artery-derived endothelial cells (PAEC) and smooth muscle cells (PASMC) was examined. S1P, a biologically active phospholipid that regulates angiogenesis, promoted PAEC chemotaxis and capillary morphogenesis; furthermore, this activity was unaltered by pretreatment with the pharmacological inhibitor of ROCK, H1152. In contrast, S1P (500 nM) significantly inhibited spontaneous PASMC chemotaxis and differentiation; however, this inhibition was eradicated upon H1152 pretreatment.

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The present study describes the characterization and evaluation of novel anticancer conjugates, 2,6-diisopropylphenol-docosahexaenoate (PP-DHA), and its analogues including 2,4-diisopropylphenol-docosahexaenoate (DIPP-DHA), 2-isopropylphenol-docosahexaenoate (IPP-DHA), 2-cyclohexanephenol-docosahexaenoate (CHP-DHA) and phenol-docosahexaenoate (P-DHA) on breast cancer cell lines. Representative breast cancer cell lines, based on estrogen alpha receptor (ER) and oncogene Her-2 expression, were used and include MDA-MB-231 (ER-negative, Her-2-negative), MCF-7 (ER-positive, Her-2-negative) AU565 (ER-negative, Her-2-positive) and MDA-MB-361 (ER-positive, Her-2-positive). The PP-DHA conjugate significantly inhibited cell growth and induced cell loss in the breast cancer cell lines similarly; however, this conjugate was not effective against normal mammary epithelial cells.

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In the present study, we investigated lipid biosynthesis in the bacterium Escherichia coli by mathematical modeling. In particular, we studied the interaction between the subsystems producing unsaturated and saturated fatty acids, phospholipids, lipid A, and cardiolipin. The present analysis was carried out both for the wild-type and for several in silico knockout mutants, using the concept of elementary flux modes.

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The existing protocols for analyzing fatty acid methyl esters (FAMEs) using a one-step acetyl chloride (AC) catalyzed transesterification and extraction procedure cannot accurately determine the medium- and long-chain fatty acids simultaneously in clinical (enteral, parenteral) formulations. For example: (1) addition of AC at room temperature generates an exothermic reaction that often results in loss of sample and possible injury to the analyst; (2) certain polyunsaturated fatty acids (PUFAs) are less stable at elevated temperatures during the transesterification and contribute to the over-estimation of the C16:0 and C18:1 fatty acids; and (3) the flame-ionization detector (FID) response varies depending on the carbon chain length of the fatty acids, that consequently impacts the underestimation of medium-chain fatty acid (C6-C10) recoveries. To overcome these deficiencies and accurately determine FAMEs, we have developed an improved one-step transesterification method that employs the addition of AC in tubes kept on a dry ice bath, the transesterification at room temperature, and the data analysis using relative response factors.

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CXCL16 is a chemokine that is expressed in both transmembrane and secreted isoforms. Both variants have been implicated in atherosclerosis. Increased CXCL16 expression on the surface of human aortic smooth muscle cells induced by interferon gamma (IFNgamma) signaling results in enhanced oxidized low density lipoprotein uptake and enhanced recruitment of pro-inflammatory cells.

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Background & Aims: Saturated fatty acids (SFAs), significant components of enteral and parenteral formulations, have been linked to cardiovascular complications. However, the effect of SFAs upon vascular inflammation is less clear. Endothelial cells (EC) play an important role in the acute inflammatory responses.

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The specific role of dietary fat in breast cancer progression is unclear, although a low-fat diet was associated with decreased recurrence of estrogen receptor alpha negative (ER(-)) breast cancer. ER(-) basal-like MDA-MB-231 and MDA-MB-436 breast cancer cell lines contained a greater number of cytoplasmic lipid droplets compared to luminal ER(+) MCF-7 cells. Therefore, we studied lipid storage functions in these cells.

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n-3 PUFA have well-recognised cardio-beneficial effects. In contrast, premature coronary deaths are associated with consumption of high levels of trans-fatty acids (TFA). The present study determined the effects of n-3 PUFA and TFA on sudden cardiac death and vascular inflammation.

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Balamuthia mandrillaris is a causative agent of granulomatous encephalitis that almost always proves fatal. A major concern during the course of therapy is that B. mandrillaris can transform into cysts.

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Valve replacement started in 1960, with the surgeon now having a significant variety of prosthetic heart valves from which to choose. These valves are broadly divided into mechanical heart valves (MHV) and bioprosthetic heart valves (BHV). Improvements in the performance and ease of usage of BHV without the need for anticoagulant therapy are among the desired features of BHV and hence the increasingly preferred choice over their mechanical counterparts.

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AIDS has changed from a mostly male-specific health problem to one that predominantly affects females. Although sex differences in HIV-1 susceptibility are beyond doubt, the extent to which sex affects the onset and progression of AIDS has remained elusive. Here, we provide evidence for an influence of X chromosomal variation on the course of retroviral infection, both in HIV-1-infected patients and in the rhesus macaque model of AIDS.

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Haematogenous spread is a key step in the development of Acanthamoeba granulomatous encephalitis, however it is not clear how circulating amoebae cross the blood-brain barrier to enter the CNS to produce disease. Using the primary human brain microvascular endothelial cells (HBMEC), which constitute the blood-brain barrier, here it is shown that Acanthamoeba abolishes the HBMEC transendothelial electrical resistance. Using traversal assays, it was observed that Acanthamoeba crosses the HBMEC monolayers.

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