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21.
Mehdi Mehrali Ehsan Moghaddam Seyed Farid Seyed Shirazi Saeid Baradaran Mohammad Mehrali Sara Tahan Latibari Hendrik Simon Cornelis Metselaar Nahrizul Adib Kadri Keivan Zandi Noor Azuan Abu Osman 《PloS one》2014,9(9)
Calcium silicate (CaSiO3, CS) ceramic composites reinforced with graphene nanoplatelets (GNP) were prepared using hot isostatic pressing (HIP) at 1150°C. Quantitative microstructural analysis suggests that GNP play a role in grain size and is responsible for the improved densification. Raman spectroscopy and scanning electron microscopy showed that GNP survived the harsh processing conditions of the selected HIP processing parameters. The uniform distribution of 1 wt.% GNP in the CS matrix, high densification and fine CS grain size help to improve the fracture toughness by ∼130%, hardness by ∼30% and brittleness index by ∼40% as compared to the CS matrix without GNP. The toughening mechanisms, such as crack bridging, pull-out, branching and deflection induced by GNP are observed and discussed. The GNP/CS composites exhibit good apatite-forming ability in the simulated body fluid (SBF). Our results indicate that the addition of GNP decreased pH value in SBF. Effect of addition of GNP on early adhesion and proliferation of human osteoblast cells (hFOB) was measured in vitro. The GNP/CS composites showed good biocompatibility and promoted cell viability and cell proliferation. The results indicated that the cell viability and proliferation are affected by time and concentration of GNP in the CS matrix. 相似文献
22.
Abu Hena Mostafa Kamal Ki-Hyun Kim Kwang-Hyun Shin Hyung-Seok Seo Hisashi Tsujimoto Hwa-Young Heo Jong-Soon Choi Chul-Soo Park Sun-Hee Woo 《Journal of Plant Biology》2009,52(6):533-542
Glutenin is a major determinant of baking performance and viscoelasticity, which are responsible for high-quality bread with
a light porous crumb structure of a well-leavened loaf. We analyzed the diversity of glutenin genes from six wheat cultivars
(Korean cvs. Keumgang and Jinpum, Chinese cvs. China-108 and Yeonnon-78, and Japanese cvs. Norin-61 and Kantou-107). Glutenins
contain two types of isoforms such as high molecular weight glutenin subunit (HMW-GS) and low molecular weight glutenin subunit
(LMW-GS). Glutenin fractions were extracted from wheat endosperm using Osborne solubility method. A total of 217 protein spots
were separated on two-dimensional gel electrophoresis with isoelectric focusing (wide range of pH 3–10). The proteins spots
were subjected to tryptic digestion and identified by matrix assisted laser desorption/ionization–time of flight mass spectrometry.
HMW-GS (43 isoforms) and LMW-GS (seven isoforms) are directly responsible for producing high-quality bread and noodles. Likewise,
all the seed storage proteins are digested to provide nutrients for the embryo during seed germination and seedling growth.
We identified the diverse glutenin subunits in wheat cultivars and compared the gluten isoforms among different wheat cultivars
according to quality. This work gives an insight on the quality improvement in wheat crop. 相似文献
23.
Lavoie C Roy L Lanoix J Taheri M Young R Thibault G Farah CA Leclerc N Paiement J 《Progress in histochemistry and cytochemistry》2011,46(1):1-48
The endoplasmic reticulum (ER) is a highly dynamic organelle. It is composed of four subcompartments including nuclear envelope (NE), rough ER (rER), smooth ER (sER) and transitional ER (tER). The subcompartments are interconnected, can fragment and dissociate and are able to reassemble again. They coordinate with cell function by way of protein regulators in the surrounding cytosol. The activity of the many associated molecular machines of the ER as well as the fluid nature of the limiting membrane of the ER contribute extensively to the dynamics of the ER. This review examines the properties of the ER that permit its isolation and purification and the physiological conditions that permit reconstitution both in vitro and in vivo in normal and in disease conditions. 相似文献
24.
Chowdhury F Rahman MA Begum YA Khan AI Faruque AS Saha NC Baby NI Malek MA Kumar AR Svennerholm AM Pietroni M Cravioto A Qadri F 《PLoS neglected tropical diseases》2011,5(4):e999
Background
In Bangladesh, increases in cholera epidemics are being documented with a greater incidence and severity. The aim of this prospective study was to identify the prevalence and importance of V. cholerae O1 and enterotoxigenic Escherichia coli (ETEC) as causal agents of severe diarrhea in a high diarrhea prone urban area in Dhaka city.Methodology
Systematic surveillance was carried out on all diarrheal patients admitted from Mirpur between March 2008 to February 2010 at the ICDDR, B hospital. Stool or rectal swabs were collected from every third diarrheal patient for microbiological evaluation.Principal Findings
Of diarrheal patients attending the hospital from Mirpur, 41% suffered from severe dehydration with 39% requiring intravenous rehydration therapy. More diarrheal patients were above five years of age (64%) than those below five years of age (36%). About 60% of the patients above five years of age had severe dehydration compared with only 9% of patients under five years of age. The most prevalent pathogen isolated was Vibrio cholerae O1 (23%) followed by ETEC (11%). About 8% of cholera infection was seen in infants with the youngest children being one month of age while in the case of ETEC the rate was 11%. Of the isolated ETEC strains, the enterotoxin type were almost equally distributed; ST accounted for 31% of strains; LT/ST for 38% and LT for 31%.Conclusion
V. cholerae O1 is the major bacterial pathogen and a cause of severe cholera disease in 23% of patients from Mirpur. This represents a socioeconomic group that best reflects the major areas of high cholera burden in the country. Vaccines that can target such high risk groups in the country and the region will hopefully be able to reduce the disease morbidity and the transmission of pathogens that impact the life and health of people. 相似文献25.
Tsitsi Mutasa-Apollo Ray W. Shiraishi Kudakwashe C. Takarinda Janet Dzangare Owen Mugurungi Joseph Murungu Abu Abdul-Quader Celia J. I. Woodfill 《PloS one》2014,9(1)
Background
Since establishment of Zimbabwe''s National Antiretroviral Therapy (ART) Programme in 2004, ART provision has expanded from <5,000 to 369,431 adults by 2011. However, patient outcomes are unexplored.Objective
To determine improvement in health status, retention and factors associated with attrition among HIV-infected patients on ART.Methods
A retrospective review of abstracted patient records of adults ≥15 years who initiated ART from 2007 to 2009 was done. Frequencies and medians were calculated for rates of retention in care and changes in key health status outcomes at 6, 12, 24 and 36 months respectively. Cox proportional hazards models were used to determine factors associated with attrition.Results
Of the 3,919 patients, 64% were female, 86% were either WHO clinical stage III or IV. Rates of patient retention at 6, 12, 24 and 36 months were 90.7%, 78.1%, 68.8% and 64.4%, respectively. After ART initiation, median weight gains at 6, 12, and 24 months were 3, 4.5, and 5.0 kgs whilst median CD4+ cell count gains at 6, 12 and 24 months were 122, 157 and 279 cells/µL respectively. Factors associated with an increased risk of attrition included male gender (AHR 1.2; 95% CI, 1.1–1.4), baseline WHO stage IV (AHR 1.7; 95% CI, 1.1–2.6), lower baseline body weight (AHR 2.0; 95% CI, 1.4–2. 8) and accessing care from higher level healthcare facilities (AHR 3.5; 95% 1.1–11.2).Conclusions
Our findings with regard to retention as well as clinical and immunological improvements following uptake of ART, are similar to what has been found in other settings. Factors influencing attrition also mirror those found in other parts of sub-Saharan Africa. These findings suggest the need to strengthen earlier diagnosis and treatment to further improve treatment outcomes. Whilst decentralisation improves ART coverage it should be coupled with strategies aimed at improving patient retention. 相似文献26.
27.
Steve Horvath Abu NM Nazmul-Hossain Rodney PE Pollard Frans GM Kroese Arjan Vissink Cees GM Kallenberg Fred KL Spijkervet Hendrika Bootsma Sara A Michie Sven U Gorr Ammon B Peck Chaochao Cai Hui Zhou David TW Wong 《Arthritis research & therapy》2012,14(6):1-13
Bone tissue has an exceptional quality to regenerate to native tissue in response to injury. However, the fracture repair process requires mechanical stability or a viable biological microenvironment or both to ensure successful healing to native tissue. An improved understanding of the molecular and cellular events that occur during bone repair and remodeling has led to the development of biologic agents that can augment the biological microenvironment and enhance bone repair. Orthobiologics, including stem cells, osteoinductive growth factors, osteoconductive matrices, and anabolic agents, are available clinically for accelerating fracture repair and treatment of compromised bone repair situations like delayed unions and nonunions. Preclinical and clinical studies using biologic agents like recombinant bone morphogenetic proteins have demonstrated an efficacy similar or better than that of autologous bone graft in acute fracture healing. A lack of standardized outcome measures for comparison of biologic agents in clinical fracture repair trials, frequent off-label use, and a limited understanding of the biological activity of these agents at the bone repair site have limited their efficacy in clinical applications. 相似文献
28.
Vaibhav K Shrivastava P Javed H Khan A Ahmed ME Tabassum R Khan MM Khuwaja G Islam F Siddiqui MS Safhi MM Islam F 《Molecular and cellular biochemistry》2012,367(1-2):73-84
The pathophysiological mechanisms leading to neuronal injury in middle cerebral artery occlusion (MCAO) model of cerebral stroke are complex and multifactorial that form the bases of behavioral deficits and inflammation mediated damage. The present study demonstrates the effect of piperine pretreatment (10 mg/kg b wt, once daily p.o. for 15 days) on cerebral ischemia-induced inflammation in male Wistar rats. The right middle cerebral artery was occluded for 2 h followed by reperfusion for 22 h. A maximum infarct volume (57.80 %) was observed in ischemic MCAO group. However, piperine administration prior to ischemia showed a significant reduction in infarct volume (28.29 %; p < 0.05) and neuronal loss (12.72 %; p < 0.01). As a result of piperine pretreatment, a significant improvement in behavioral outputs of MCAO rats (p < 0.05-0.01) was observed. Piperine successfully reduced the level of proinflammatory cytokines IL-1β, IL-6 and TNF-α, in ischemic group (p < 0.01). Ischemic group brain has shown edematous morphology with vacuolated architecture and pyknotic nuclei in H & E staining which was successfully ameliorated by piperine administration. Moreover, piperine also succeeded in lowering the expression of COX-2, NOS-2, and NF-κB (p < 0.01). Both cytosolic and nuclear NF-κB were down-regulated in ischemic group pre-administered with piperine (p < 0.01). The present study suggests that piperine is able to salvage the ischemic penumbral zone neurons by virtue of its anti-inflammatory property, thereby limiting ischemic cell death. 相似文献
29.
Oh C Heo SJ De Zoysa M Affan A Jung WK Park HS Lee Y Lee J Yoon KT Kang DH 《Journal of bacteriology》2011,193(19):5557
We isolated Mesoflavibacter zeaxanthinifaciens S86 as xylanase-producing bacteria from seawater sampled in Micronesia. Analysis of the M. zeaxanthinifaciens genome revealed that it contains a single circular chromosome of 3,704,661 bp with 3,249 putative open reading frames. 相似文献
30.
Shubha Priyamvada Sara A. Khan Md.Wasim Khan Sheeba Khan Neelam Farooq Farah Khan A.N.K. Yusufi 《Prostaglandins, leukotrienes, and essential fatty acids》2010,82(1):35-44
Human and animal exposure demonstrates that uranium is nephrotoxic. However, attempts to reduce it were not found suitable for clinical use. Dietary fish oil (FO) enriched in ω-3 fatty acids reduces the severity of cardiovascular and renal diseases. Present study investigates the protective effect of FO on uranyl nitrate (UN)-induced renal damage. Rats prefed with experimental diets for 15 days, given single nephrotoxic dose of UN (0.5 mg/kg body weight) intraperitoneally. After 5 d of UN treatment, serum/urine parameters, enzymes of carbohydrate metabolism, brush border membrane (BBM), oxidative stress and phosphate transport were analyzed in rat kidney. UN nephrotoxicity was characterized by increased serum creatinine and blood urea nitrogen. UN increased the activity of lactate dehydrogenase and NADP-malic enzyme whereas decreased malate, isocitrate and glucose-6-phophate dehydrogenases; glucose-6-phophatase, fructose-1, 6-bisphosphatase and BBM enzyme activities. UN caused oxidant/antioxidant imbalances as reflected by increased lipid peroxidation, activities of superoxide dismutase, glutathione peroxidase and decreased catalase activity. Feeding FO alone increased activities of enzymes of glucose metabolism, BBM, oxidative stress and Pi transport. UN-elicited alterations were prevented by FO feeding. However, corn oil had no such effects and was not similarly effective. In conclusion, FO appears to protect against UN-induced nephrotoxicity by improving energy metabolism and antioxidant defense mechanism. 相似文献