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241.
N. Manzoor O. Anwar Bég S. Shaheen 《Computer methods in biomechanics and biomedical engineering》2019,22(7):685-695
Bionic systems frequently feature electromagnetic pumping and offer significant advantages over conventional designs via intelligent bio-inspired properties. Complex wall features observed in nature also provide efficient mechanisms which can be utilized in biomimetic designs. The characteristics of biological fluids are frequently non-Newtonian in nature. In many natural systems super-hydrophobic slip is witnessed. Motivated by these phenomena, in this paper, we discussed a mathematical model for the cilia-generated propulsion of an electrically-conducting viscoelastic physiological fluid in a ciliated channel under the action of magnetic field. The rheological behavior of the fluid is simulated with the Johnson-Segalman constitutive model which allows internal wall slip. The regular or coordinated movement of the ciliated edges (which line the internal walls of the channel) is represented by a metachronal wave motion in the horizontal direction which generates a two-dimensional velocity profile. This mechanism is imposed by a periodic boundary condition which generates propulsion in the channel flow. Under the classical lubrication approximation, the boundary value problem is non-dimensionalized and solved analytically with a perturbation technique. The influence of the geometric, rheological (slip and Weissenberg number) and magnetic parameters on velocity, pressure gradient and the pressure rise (evaluated via the stream function in symbolic software) are presented graphically and interpreted at length. 相似文献
242.
Ali Muhammad Mehmood Azra Anjum Muhammad Sohail Tarrar Moazzam Nazir Khan Shaheen N. Riazuddin Sheikh 《Molecular and cellular biochemistry》2015,403(1-2):267-276
Molecular and Cellular Biochemistry - Type 1 diabetes mellitus (DM) is a strong risk factor for the development of diabetic cardiomyopathy (DCM) which is the leading cause of morbidity and... 相似文献
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The Notch pathway contributes to self-renewal of tumor-initiating cell and inhibition of normal colonic epithelial cell differentiation. Deregulated expression of Notch1 and Jagged1 is observed in colorectal cancer. Hairy/enhancer of split (HES) family, the most characterized targets of Notch, involved in the development of many cancers. In this study, we explored the role of Hes1 in the tumorigenesis of colorectal cancer. Knocking down Hes1 induced CRC cell senescence and decreased the invasion ability, whereas over-expression of Hes1 increased STAT3 phosphorylation activity and up-regulated MMP14 protein level. We further explored the expression of Hes1 in human colorectal cancer and found high Hes1 mRNA expression is associated with poor prognosis in CRC patients. These findings suggest that Hes1 regulates the invasion ability through the STAT3-MMP14 pathway in CRC cells and high Hes1 expression is a predictor of poor prognosis of CRC. 相似文献
246.
A genome‐scale screen reveals context‐dependent ovarian cancer sensitivity to miRNA overexpression 下载免费PDF全文
Benjamin B Shields Chad V Pecot Hua Gao Elizabeth McMillan Malia Potts Christa Nagel Scott Purinton Ying Wang Cristina Ivan Hyun Seok Kim Robert J Borkowski Shaheen Khan Cristian Rodriguez‐Aguayo Gabriel Lopez‐Berestein Jayanthi Lea Adi Gazdar Keith A Baggerly Anil K Sood Michael A White 《Molecular systems biology》2015,11(12)
Large‐scale molecular annotation of epithelial ovarian cancer (EOC) indicates remarkable heterogeneity in the etiology of that disease. This diversity presents a significant obstacle against intervention target discovery. However, inactivation of miRNA biogenesis is commonly associated with advanced disease. Thus, restoration of miRNA activity may represent a common vulnerability among diverse EOC oncogenotypes. To test this, we employed genome‐scale, gain‐of‐function, miRNA mimic toxicity screens in a large, diverse spectrum of EOC cell lines. We found that all cell lines responded to at least some miRNA mimics, but that the nature of the miRNA mimics provoking a response was highly selective within the panel. These selective toxicity profiles were leveraged to define modes of action and molecular response indicators for miRNA mimics with tumor‐suppressive characteristics in vivo. A mechanistic principle emerging from this analysis was sensitivity of EOC to miRNA‐mediated release of cell fate specification programs, loss of which may be a prerequisite for development of this disease. 相似文献
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Hepatitis C is one of the common types of chronic liver disease, and its plausible association with trace metal imbalance
has been investigated in the present study. The blood samples of hepatitis C patients and healthy donors were analysed for
trace metals (Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Pb, and Zn) by flame atomic absorption spectrophotometry after wet
acid digestion. In the blood of the hepatitis patients, mean concentrations of essential metals, Na, K, Fe, Ca, Mg, and Zn,
were 918.7, 361.0, 102.5, 20.00, 24.66, and 9.429 ppm, respectively, while the mean metal levels in the blood of healthy donors
were 1509, 406.8, 232.5, 28.35, 24.59, and 8.799 ppm, respectively. On the average, Cr was significantly higher, while Na,
Fe, Ca, Cu, Mn, Pb, and Cd were comparatively lower in the blood of the patients. The correlation study manifested significantly
divergent mutual relationships of trace metals in the blood of the patients and healthy donors. Multivariate statistical methods
revealed considerably diverse distribution of trace metals in the two groups. Dissimilarity in the trace metal distribution
was also noted with the gender and residential location of the donors in both groups. 相似文献
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