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Ebrahim Abbasi-Oshaghi,1,2,* Fatemeh Mirzaei,2,* Mona Pourjafar3 1Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran; 2Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran; 3Student Research Committee, Hamadan University of Medical Sciences, Hamadan, Iran *These authors contributed equally to this work Purpose: This study evaluated the effects of titanium dioxide nanoparticles (TiO2 NPs) on liver and intestine of normal rats. Methods: Male rats were divided into four groups as follows: 1) control rats, 2) control rats that orally received 10 mg/kg TiO2 NPs, 3) control rats that orally received 50 mg/kg TiO2 NPs, and 4) control rats that orally received 100 mg/kg TiO2 NPs. After 30 days, the NLRP3 inflammasome pathway (NLRP3, caspase-1, and IL-1β), antioxidant pathway (superoxide dismutase [SOD], glutathione peroxidase [GPx], and catalase [CAT]), inflammatory pathway (inducible nitric oxide synthase [iNOS] and tumor necrosis factor-α [TNF-α]), and the apoptosis pathway (p53, Bax, Bcl-2, and caspase-3) were determined in the intestine and liver of the rats. H&E and Masson’s trichrome (MT) staining as well as TUNEL assay were used to examine the liver and the intestine. Biochemical factors, cytotoxicity, ROS generation, and apoptosis rate were also determined in HepG2 and Caco-2 cells.Results: TiO2 NPs in a dose-dependent manner increased cytotoxicity, oxidative stress, and apoptosis rate in Caco-2 and HepG2 cells. The administration of TiO2 NPs significantly reduced antioxidant enzyme activity and gene expressions (SOD, CAT, and GPx) as well as glutathione (GSH) levels and total antioxidant capacity (TAC) in a dose-dependent manner. TiO2 NPs also induced the apoptosis pathway and inflammatory pathway gene expressions and caspase-3 activity in the intestine and liver. TUNEL assay was in agreement with gene expressions. TiO2 NPs also led to morphological changes in the liver and intestine.Conclusion: TiO2 NPs could have cytotoxic effects on the intestine and liver structure and function by inducing oxidative stress, inflammation, and apoptosis. Keywords: caco-2 cells, hepg2 cells, gene expression, rat

Interfacial stability of purelv-viscous fluids is numerically investigated in channel flow. It is assumed that the main fluid (i.e., the fluid flowing through the center of the channel) is thixotropic and obeys the Moore model as its constitutive equation while the fluids flowing above and below this central (core) layer are assumed to be the same Newtonian fluids with the same thickness. Having found an analytical solution for the base-flow in all three layers, a temporal, normal-mode, linear stability analysis is employed to investigate the vulnerability of the base flow to small perurbations. An eigenvalue problem is obtained this way which is solved numerically using the pseudo-spectral collocation method. The main objective of the work is to explore the role played by the time-constant introduced through the core fluid's thixotropic behavior on the critical Reynolds number. It is found that the thixotropic behavior of the core fluid has a stabilizing effect on the interface. An increase in the viscosity of the upper/lower Newtonian fluids is predicted to have a stabilizing or destabilizing effect on the interface depending on the parameter values of the Moore model (e.g., the ratio of the zero-shear viscosity to infinite-shear viscosity in this fluid model). [ABSTRACT FROM AUTHOR]

Linear stability of a thixotropic fluid obeying the Moore model is investigated in pipe flow using a temporal stability analysis in which infinitesimally small perturbations, represented by normal modes, are superimposed on the base flow and their evolution in time is monitored in order to detect the onset of instability. An eigenvalue problem is obtained, which is solved numerically using the pseudo-spectral Chebyshev-based collocation method. The neutral instability curve is plotted as a function of the thixotropy number of the Moore model. Based on the results obtained in this work, it is concluded that the thixotropic behavior of the Moore fluid has a destabilizing effect on pipe flow. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer is the fourth leading cause of death. Various natural compounds are known to have antitumor properties. Garcinol, a polyisoprenylated benzophenone, has antioxidant and anti-inflammatory properties. In the current study, we investigated the anticancer activity of garcinol on human colorectal adenocarcinoma cell line (HT-29) human colon cancer cells. Methods: HT-29 cells were treated with various concentrations of garcinol for 24 h. The effect of garcinol on HT-29 cells proliferation was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay; the mRNA expression of microsomal prostaglandin E synthase-1 (mPGES-1), hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF), C-X-C chemokine receptor type 4 (CXCR4), matrix metalloproteinase-2 (MMP-2), and matrix metalloproteinase-9 (MMP-9) were examined by quantitative real-time polymerase chain reaction; apoptosis was detected by proportion of sub-G1 cell; caspase 3 activity and prostaglandin E2 (PGE2) level were determined by enzyme-linked immunosorbent assay and HT-29 cells migration was assessed using scratch test. Results: Garcinol preconditioning markedly decreased the expression of mPGES-1, HIF-1α, VEGF, CXCR4, MMP-2, and MMP-9. The proportion of cells in sub-G1 phase and caspase 3 activity were increased by garcinol treatment whereas the cell proliferation, PGE2 level, and cell migration were decreased in these cells, compared to the control group. Conclusion: Our findings suggest that garcinol plays a critical role in elevating apoptosis and inhibiting HT-29 cells proliferation, angiogenesis, and invasion by suppressing the mPGES-1/PGE2/HIF-1α signaling pathways. [ABSTRACT FROM AUTHOR]

The rapid and uncontrolled haphazard urbanization is a serious threat to the manmade and natural environment and the socio-economic balance of our time. There is a global concern that urbanization must be oriented in responsible, sustainable, and livable urban forms. High quality of sustainable urban design plays a key role in creating these sustainable living environments. In this regard, learning from culture and history and searching together are vital for new ways of designing. In this paper, the evolution of the settlements with respect to sustainable urban design in past, present, and future is analyzed. The study indicates that we had sustainable urban design in pre-industrial period in an organic way; however, we altered the existing ecosystems by welcoming incompatible technological elements; elements that cause a kind of ill growth similar to cancer. In this relation, a case study of urban environmental design for Darabad River Valley in Tehran as a sustainable urban design project is presented briefly. Finally, it is concluded that we should know that designing is a kind of altering the systems. A comprehensive wise and conscious approach similar to what we have used in Darabad River Valley project is suggested for similar situations. [ABSTRACT FROM AUTHOR]

Fifteen clinically healthy non-pregnant 4-year-old Iranian Najdi does were divided into 3 equal experimental groups (n=5) and received different doses of furosemide intravenously (Group 1: 2.5 mg.kg-1; Group 2: 5 mg.kg-1 and Group 3: 10 mg.kg-1). Electrocardiogram recordings and blood samplings to evaluate serum sodium, potassium, chloride, calcium, magnesium and phosphorus concentrations were performed prior and 1, 2, 3, 4, 5 and 24 hours after furosemide administration. In Group 3, R amplitude at 5th hour was significantly different from other experimental groups (P=0.001) and significantly higher than baseline level (P=0.001). P-R, R-R and S-T intervals in Group 3 at 5th hour were significantly higher than in other groups (P<0.05). These parameters in Group 3 at this time were significantly higher than baseline values (P<0.05). In all 3 experimental groups, serum concentrations of sodium, chloride and potassium at 5th hour were significantly lower than baseline levels at hour zero. It may be suggested that changes of electrocardiographic parameters after furosemide administration are due to alterations of the electrical conduction of action potential in the myocardium. [ABSTRACT FROM AUTHOR]

The experiment evaluated the effects of intravenous administration of polymyxin B on experimental endotoxaemia in sheep.

Five clinically healthy 1-year old Iranian fat-tailed ewes (25±1.5 kg body weight) were randomly selected and lipopolysaccharide from Escherichia coli serotype O55:B5 was infused intravenously to induce endotoxaemia at 20 µg/kg. Blood samplings and serum separations were performed prior and 1, 2, 3, 4, 5, 6 and 24 hours after lipopolysaccharide injection and values of serum homocysteine, cardiac troponin I, creatine kinase isoenzyme MB and lactate dehydrogenase were assayed. A rapid and significant elevation of all studied parameters was seen after endotoxaemia induction. There were positive correlations among homocysteine, cardiac troponin I, creatine kinase isoenzyme MB and lactate dehydrogenase at all hours after endotoxaemia induction. The results of the current experimental study provide evidence for associations among these biomarkers and their changes during endotoxaemia and the data can be useful for assessing suspected cases of myocardial diseases and its changes may be of diagnostic and prognostic values. [ABSTRACT FROM AUTHOR]

The present study was performed to find out the prevalence of cardiac arrhythmias in clinically healthy Iranian Najdi goats at a different age, without any clinical signs of cardiac diseases. The animals (n=118) were assigned into 6 age groups, including 15-day-old (n=17), 2-month-old (n=23), 6-month-old (n=22), 1-year-old (n=11), 3-year-old (n=22) and 5-year-old (n=23). In 53.3% of all studied goats, at least one type of cardiac arrhythmia was seen. Four types of cardiac arrhythmias were detected in this study, including sinus tachycardia, respiratory sinus arrhythmia, sinoatrial block and ventricular premature complex. The proportion of cardiac arrhythmias differed significantly (P<0.05) between 15-day-old animals and all other age groups. Since none of the goats with cardiac arrhythmias showed any clinical signs of heart disease at the time of electrocardiogramme recordings, the arrhythmias observed in this study could be considered as physiological ones. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate serum concentrations of serum amyloid A (SAA), haptoglobin (Hp), interferon-gamma (INF-γ) and tumor necrosis factor-a (TNF-α) in dairy calves affected with diarrhoea during the first 4 weeks of life, with special reference to etiological agents. To study the acute phase reaction in infectious diarrhoea with E. coli k99, rota and corona viruses and Cryptosporidium parvum, 50 clinically healthy and 50 diarrhoeic calves 1-28 days of age were randomly selected. Blood samples were taken from jugular vein and serum concentrations of serum amyloid A (SAA), haptoglobin (Hp), interferon-gamma (INF-γ) and tumor necrosis factor-a (TNF-α) were determined. Although all studied acute phase response indicators were significantly increased in diarrhoeic calves, SAA and Hp were two major acute phase proteins that were remarkably increased (p<0.05) compared to healthy animals. According to this study, the SAA and Hp correlated with faecal scores and proved to be reliable indicators of the severity of diarrhea (Spearman rho = 0.22 and 0.23, respectively, P=0.05). [ABSTRACT FROM AUTHOR]