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981.
Ratnam Wickneswari M. A. R. Bhuiyan Sabu Kalluvettankuzhy K. Li Sze Lim Michael J. Thomson Md. Kairudin Narimah Md. Zain Abdullah 《Plant Molecular Biology Reporter》2012,30(4):929-939
A backcross breeding strategy was used to identify quantitative trait loci (QTLs) associated with 14 traits in a BC2F2 population derived from a cross between MR219, an indica rice cultivar and an accession of Oryza rufipogon (IRGC 105491). A total of 261 lines were genotyped with 96 microsatellite markers and evaluated for plant morphology, yield components and growth period. The genetic linkage map generated for this population with an average interval size of 16.2?cM, spanning 1,553.4?cM (Kosambi) of the rice genome. Thirty-eight QTLs were identified with composite interval mapping (CIM), whereas simple interval mapping (SIM) resulted in 47 QTLs (LOD >3.0). The O. rufipogon allele was favourable for 59% of QTLs detected through CIM. Of 261 BC2F2 families, 26 advanced backcross breeding lines (BC2F5) were used for QTL validation. These lines were selected on the basis of the yield traits potentiality in BC2F3 and BC2F4 generations. The field trial was conducted at three different locations in Malaysia using randomized complete block design with three replications. Trait based marker analysis was done for QTL determination. Twenty-five QTLs were detected in BC2F5 generation whereas 29 QTLs were detected in BC2F2 generation of the same population. Two QTLs (qPL-1 and qSPL-7) were not considered for validation due to their low R 2 values and two QTLs (qPSS-3-2 and qGW-3-2) were not detected in the BC2F5 population. Fifteen QTLs showed the beneficial effect to enhance the trait value of the breeding lines. QTL validation aided to select the promising lines for further utilization. 相似文献
982.
This study examines the effects of Ramadan fasting on performance during an intense exercise session performed at three different times of the day, i.e., 08:00, 18:00, and 21:00?h. The purpose was to determine the optimal time of the day to perform an acute high-intensity interval exercise during the Ramadan fasting month. After familiarization, nine trained athletes performed six 30-s Wingate anaerobic test (WAnT) cycle bouts followed by a time-to-exhaustion (T(exh)) cycle on six separate randomized and counterbalanced occasions. The three time-of-day nonfasting (control, CON) exercise sessions were performed before the Ramadan month, and the three corresponding time-of-day Ramadan fasting (RAM) exercise sessions were performed during the Ramadan month. Note that the 21:00?h session during Ramadan month was conducted in the nonfasted state after the breaking of the day's fast. Total work (TW) completed during the six WAnT bouts was significantly lower during RAM compared to CON for the 08:00 and 18:00?h (p?.017; effect size [d]?=?.55 [small] and .39 [small], respectively) sessions, but not for the 21:00?h (p?=?.03, d?=?.18 [trivial]) session. The T(exh) cycle duration was significantly shorter during RAM than CON in the 18:00 (p < .017, d?=?.93 [moderate]) session, but not in the 08:00 (p?=?.03, d?=?.57 [small]) and 21:00?h (p?=?.96, d?=?.02 [trivial]) sessions. In conclusion, Ramadan fasting had a small to moderate, negative impact on quality of performance during an acute high-intensity exercise session, particularly during the period of the daytime fast. The optimal time to conduct an acute high-intensity exercise session during the Ramadan fasting month is in the evening, after the breaking of the day's fast. (Author correspondence: abdul_rashid_aziz@ssc.gov.sg ). 相似文献
983.
Susan Quach Jemila S. Hamid Jennifer A. Pereira Christine L. Heidebrecht Shelley L. Deeks Natasha S. Crowcroft Sherman D. Quan Stephanie Brien Jeffrey C. Kwong 《CMAJ》2012,184(15):1673-1681
Background:
The success of influenza vaccination campaigns may be suboptimal if subgroups of the population face unique barriers or have misconceptions about vaccination. We conducted a national study to estimate influenza vaccine coverage across 12 ethnic groups in Canada to assess the presence of ethnic disparities.Methods:
We pooled responses to the Canadian Community Health Survey between 2003 and 2009 (n = 437 488). We estimated ethnicity-specific self-reported influenza vaccine coverage for the overall population, for people aged 65 years and older, and for people aged 12–64 years with and without chronic conditions. We used weighted logistic regression models to examine the association between ethnicity and influenza vaccination, adjusting for sociodemographic factors and health status.Results:
Influenza vaccination coverage ranged from 25% to 41% across ethnic groups. After adjusting for sociodemographic factors and health status for people aged 12 years and older, all ethnic groups were more likely to have received a vaccination against influenza than people who self-identified as white, with the exception of those who self-identified as black (odds ratio [OR] 1.01, 95% confidence interval [CI] 0.88–1.15). Compared with white Canadians, Canadians of Filipino (OR 2.00, 95% CI 1.67–2.40) and Southeast Asian (OR 1.66, 95% CI 1.36–2.03) descent had the greatest likelihood of having received vaccination against influenza.Interpretation:
Influenza vaccine coverage in Canada varies by ethnicity. Black and white Canadians have the lowest uptake of influenza vaccine of the ethnic groups represented in our study. Further research is needed to understand the facilitators, barriers and misconceptions relating to vaccination that exist across ethnic groups, and to identify promotional strategies that may improve uptake among black and white Canadians.Accurate and reliable data on vaccine coverage are essential for evaluating the success of influenza vaccination campaigns. Identifying populations with suboptimal coverage can help program planners design effective, targeted health-promotion strategies. Vaccine coverage has traditionally been described by age and sex;1 little research in Canada has examined coverage by ethnicity.Many studies in the United States have shown large ethnic disparities (> 15%) in coverage between people who self-identify as white, black or Hispanic among adults with high-risk conditions,2 older adults3,4 and Medicare beneficiaries.5 The reasons for these disparities are complex and may be related to attitudes and knowledge about vaccination, access to health care, socioeconomic status and provider bias.6 However, these findings cannot be applied to the Canadian population, which is distinct in terms of the delivery of influenza vaccinations and ethnic composition. Since the late 1970s, the number of non-European immigrants to Canada has risen, contributing to a substantial increase in the visible minority population, from 4.7% of the total population in 1981 to 16.2% in 2006.7 More than 200 different ethnic origins were reported in the 2006 Census,8 with people of South Asian (4.0%), Chinese (3.9%) and black (2.5%) heritage representing the largest proportions of the population.Canada’s National Advisory Committee on Immunization recommends vaccination against influenza for people at high risk of serious infection and their contacts.9 The largest risk groups are adults 65 years of age and older and people with certain chronic medical conditions (e.g., cardiac and pulmonary disorders, diabetes, cancer, immune-compromising conditions, renal disease, anemia and obesity). Every province and territory provides free influenza vaccinations to these priority groups. Since 2000, Ontario has provided publicly funded influenza vaccinations to all people older than 6 months of age. Other jurisdictions (Alberta, Manitoba, Saskatchewan, Nova Scotia, Nunavut, Yukon and Northwest Territories) have subsequently adopted similar programs.10 Although these initiatives should reduce financial barriers to vaccination, there may be other barriers or misconceptions unique to specific groups that affect behaviour.The purpose of this study was to estimate influenza vaccine coverage across 12 ethnic groups in Canada to assess possible disparities. 相似文献984.
The effect of three-dimensional shape optimization on the probabilistic response of a cemented femoral hip prosthesis 总被引:2,自引:0,他引:2
Probabilistic analyses allow the effect of uncertainty in system parameters on predicted model performance measures to be determined. Furthermore, using performance functions to describe a failure event, the probability of failure can be quantified. The effect of three-dimensional prosthesis shape optimization on the probabilistic response and failure probability of a cemented hip prosthesis system is investigated. Random variables include joint and muscle loading, cortical and cancellous bone and PMMA bone cement elastic properties, and strength parameters describing failure of the bone cement and the prosthesis-bone cement interface. Several performance functions describing the bone cement and prosthesis-cement interface are used to compute the probability of failure. When evaluated deterministically, most performance functions indicated a safe design, with the exception of interface tensile failure. However, when evaluated probabilistically, finite probabilities of failure were computed, some significant. The most likely mode of failure before shape optimization was prosthesis-bone cement interface tensile failure with a predicted probability of failure of 97.9%. Deterministic prosthesis shape optimization reduced the probability of failure for all performance functions and reduced prosthesis-bone cement interface tensile failure by 31.7%. Probability sensitivity factors indicate that the uncertainty in the joint loading, cement strength, and implant-cement interface strength have the greatest effect on the computed probability of failure. Implant shape optimization results in a more robust implant design that is less sensitive to uncertainties in joint loading, which cannot be easily controlled, and more sensitive to cement and interface properties, which are easier to modify. 相似文献
985.
986.
Zakaria ZA Raden Mohd Nor RN Hanan Kumar G Abdul Ghani ZD Sulaiman MR Rathna Devi G Mat Jais AM Somchit MN Fatimah CA 《Canadian journal of physiology and pharmacology》2006,84(12):1291-1299
The present study was carried out to establish the antinociceptive, anti-inflammatory, and antipyretic properties of the aqueous extract of Melastoma malabathricum leaves in experimental animals. The antinociceptive activity was measured using abdominal constriction, hot-plate, and formalin tests, whereas the anti-inflammatory and antipyretic activities were measured using carrageenan-induced paw edema and brewer's yeast-induced pyrexia tests, respectively. The extract, which was obtained after soaking the air-dried leaves in distilled water for 72 h and then preparing in concentrations of 10%, 50%, and 100% (v/v), was administered subcutaneously 30 min prior to subjection to the above mentioned assays. At all concentrations tested, the extract was found to exhibit significant (P < 0.05) antinociceptive, anti-inflammatory, and antipyretic activities in a concentration-independent manner. Our findings that the aqueous extract of M. malabathricum possesses antinociceptive, anti-inflammatory, and antipyretic activities supports previous claims on its traditional uses to treat various ailments. 相似文献
987.
Enhanced immunogenicity of heat shock protein 70 peptide complexes from dendritic cell-tumor fusion cells 总被引:7,自引:0,他引:7
Enomoto Y Bharti A Khaleque AA Song B Liu C Apostolopoulos V Xing PX Calderwood SK Gong J 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(9):5946-5955
We have developed a molecular chaperone-based tumor vaccine that reverses the immune tolerance of cancer cells. Heat shock protein (HSP) 70 extracted from fusions of dendritic (DC) and tumor cells (HSP70.PC-F) possess superior properties such as stimulation of DC maturation and T cell proliferation over its counterpart from tumor cells. More importantly, immunization of mice with HSP70.PC-F resulted in a T cell-mediated immune response including significant increase of CD8 T cells and induction of the effector and memory T cells that was able to break T cell unresponsiveness to a nonmutated tumor Ag and provide protection of mice against challenge with tumor cells. By contrast, the immune response to vaccination with HSP70-PC derived from tumor cells is muted against such nonmutated tumor Ag. HSP70.PC-F complexes differed from those derived from tumor cells in a number of key manners, most notably, enhanced association with immunologic peptides. In addition, the molecular chaperone HSP90 was found to be associated with HSP70.PC-F as indicated by coimmunoprecipitation, suggesting ability to carry an increased repertoire of antigenic peptides by the two chaperones. Significantly, activation of DC by HSP70.PC-F was dependent on the presence of an intact MyD88 gene, suggesting a role for TLR signaling in DC activation and T cell stimulation. These experiments indicate that HSP70-peptide complexes (PC) derived from DC-tumor fusion cells have increased their immunogenicity and therefore constitute an improved formulation of chaperone protein-based tumor vaccine. 相似文献
988.
Carmichael MD Davis JM Murphy EA Brown AS Carson JA Mayer EP Ghaffar A 《American journal of physiology. Regulatory, integrative and comparative physiology》2006,291(5):R1344-R1348
Brain cytokines, induced by various inflammatory challenges, have been linked to sickness behaviors, including fatigue. However, the relationship between brain cytokines and fatigue after exercise is not well understood. Delayed recovery of running performance after muscle-damaging downhill running is associated with increased brain IL-1beta concentration compared with uphill running. However, there has been no systematic evaluation of the direct effect of brain IL-1beta on running performance after exercise-induced muscle damage. This study examined the specific role of brain IL-1beta on running performance (either treadmill or wheel running) after uphill and downhill running by manipulating brain IL-1beta activity via intracerebroventricular injection of either IL-1 receptor antagonist (ra; downhill runners) or IL-1beta (uphill runners). Male C57BL/6 mice were assigned to the following groups: uphill-saline, uphill-IL-1beta, downhill-saline, or downhill-IL-1ra. Mice initially ran on a motor-driven treadmill at 22 m/min and -14% or +14% grade for 150 min. After the run, at 8 h (wheel cage) or 22 h (treadmill), uphill mice received intracerebroventricular injections of IL-1beta (900 pg in 2 microl saline) or saline (2 microl), whereas downhill runners received IL-1ra (1.8 microg in 2 microl saline) or saline (2 microl). Later (2 h), running performance was measured (wheel running activity and treadmill run to fatigue). Injection of IL-1beta significantly decreased wheel running activity in uphill runners (P<0.01), whereas IL-1ra improved wheel running in downhill runners (P<0.05). Similarly, IL-1beta decreased and Il-1ra increased run time to fatigue in the uphill and downhill runners, respectively (P<0.01). These results support the hypothesis that increased brain IL-1beta plays an important role in fatigue after muscle-damaging exercise. 相似文献
989.
Hu Q Wang X Lee J Mansoor A Liu J Zeng L Swingen C Zhang G Feygin J Ochiai K Bransford TL From AH Bache RJ Zhang J 《American journal of physiology. Heart and circulatory physiology》2006,291(2):H648-H657
Regions of myocardial infarct (MI) are surrounded by a border zone (BZ) of normally perfused but dysfunctional myocardium. Although systolic dysfunction has been attributed to elevated wall stress in this region, there is evidence that intrinsic abnormalities of contractile performance exist in BZ myocardium. This study examined whether decreases of high-energy phosphates (HEP) and mitochondrial F(1)F(0)-ATPase (mtATPase) subunits typical of failing myocardium exist in BZ myocardium of compensated postinfarct remodeled hearts. Eight pigs were studied 6 wk after MI was produced by ligation of the left anterior descending coronary artery (LAD) distal to the second diagonal. Animals developed compensated LV remodeling with a decrease of ejection fraction from 54.6 +/- 5.4% to 31 +/- 2.1% (MRI) 5 wk after LAD occlusion. The remote zone (RZ) myocardium demonstrated modest decreases of ATP and mtATPase components. In contrast, BZ myocardium demonstrated profound abnormalities with ATP levels decreased to 42% of normal, and phosphocreatine-to-ATP ratio ((31)P-magnetic resonance spectroscopy) decreased from 2.06 +/- 0.19 in normal hearts to 1.07 +/- 0.10, with decreases in alpha-, beta-, OSCP, and IF(1) subunits of mtATPase, especially in the subendocardium. The reduction of myocardial creatine kinase isoform protein expression was also more severe in the BZ relative to the RZ myocardium. These abnormalities were independent of a change in mitochondrial content because the mitochondrial citrate synthase protein level was not different between the BZ and RZ. This regional heterogeneity of ATP content and expression of key enzymes in ATP production suggests that energetic insufficiency in the peri-infarct region may contribute to the transition from compensated LV remodeling to congestive heart failure. 相似文献
990.
Purified glucoamylase from Arachniotus citrinus was immobilized on polyacrylamide gel with 70% yield of immobilization. The immobilization improved the pH optima, temperature optima, values of K(m), V(max), and activation energy. Irreversible thermal denaturation studies of soluble and immobilized glucoamylase indicated that immobilization decreased the entropy and enthalpy of deactivation by magnitudes and made the immobilized glucoamylase thermodynamically more stable. 相似文献