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81.
82.
Grdina David J.; Nagy Biserka; Hill Colin K.; Wells Robert L.; Peraino Carl 《Carcinogenesis》1985,6(6):929-931
N-(2-mercaptoethyl)-lt3-diaminopropane (WR1065) protects againstradiation-induced cell killing and mutagenesis at the hypoxanthine-guaninephosphoribosyl transferase (HGPRT) locus in V79 Chinese hamsterhing fibroblast cells. At a concentration of 4 mM, WR1065 wasfound to be effective in protecting against radiation-inducedcell lethality only if present during irradiation, e.g., a dosemodification factor (DMF) of 1.9. No protective effect was observedif the protector was added within 5 min after irradiation or3 h later, e.g., DMFs of 1.0 and 1.1, respectively. The effectof WR1065 on radiation-induced mutation, expressed as resistanceto the cytotoxic purine analogue 6-thioguanine (HGPRT), wasalso investigated. In contrast to the treatment-schedule dependencefor protection by WR1065 against cell killing, this agent waseffective in reducing radiation-induced mutations regardlessof when it was administered. Following a dose of 10 Gy of 60Co-rays, the mutation frequencies observed per 106 survivors were77 ± 8, 27 ± 6, 42 ± 7, and 42 ±7 for radiation only, and WR1065 present during, immediatelyafter, or 3 h after irradiation. These data suggest that althougha segment of radiation-induced damage leading to reproductivedeath cannot be modulated through the postirradiation actionof WR1065, processes leading to the fixation of gross geneticdamage and mutation induction in surviving cells can be effectivelyaltered and interfered with leading to a marked reduction inmutation frequency. 相似文献
83.
Lerebours E Ducable G Francheschi A Saour N Colin R 《Clinical nutrition (Edinburgh, Scotland)》1985,4(3):135-138
Catheter obstruction is a serious incident during prolonged parenteral nutrition (PN). This retrospective study was carried out in order to compare the frequencies of catheter obstruction with nutritive mixtures in bags according to whether or not lipids were mixed with the entire 24 h nutritional supply (Group I, n=33) or infused separately (Group II, n=30). Our results show that obstructions are significantly more frequent in Group I (11 13 ) than in group 2 (3 10 ), appearing within a mean interval of 29 days after inserting the catheter. The global percentages of patients undergoing cyclic PN were the same in both patient groups. In group I, however, the percentage of patients on cyclic PN was significantly higher for the obstructed catheters (100%) than for the unobstructed catheters (59%). In conclusion, the mixture of lipids with the remainder of the nutrients in the conditions of this study is the prime cause of catheter obstruction, although the exact mechanism is not elucidated. The role of cyclic PN appears to be accessory. 相似文献
84.
Peter Molenaar Grant A. McPherson Errol Malta Colin Raper 《Naunyn-Schmiedeberg's archives of pharmacology》1985,331(2-3):240-246
Summary The affinity and efficacy of a number of sympathomimetic amines structurally related to prenalterol and the selective 1-adrenoceptor agonist RO 363 were determined using a combination of radioligand binding and organ bath techniques. Affinity of the molecules (pK
D) was calculated from their ability to displace the radioligand [125I]iodocyanopindolol ([125I]CYP) from -adrenoceptor sites in left atrial (1) and uterine (2) membrane homogenates. These pK
D values were used to calculate efficacy from the positive inotropic and uterine relaxant responses elicited by the drugs in organ bath experiments. The drugs studied were either arylethanolamines i.e., (–)-isoprenaline (ISO), p-hydroxyisoprenaline (pOH-ISO), compounds XIV and XVI or aryloxypropanolamine-derivatives, i.e., oxymethylene-isoprenaline (OM-ISO), prenalterol and Compound XI which possessed ap-phenol or catechol ring and an isopropyl or a homoveratryl amine substituent. Only ISO, OM-ISO, pOH-ISO and Compound XVI were active as agonists in both tissue preparations. These drugs were partial agonists which exhibited a wide range of pD2 values and did not display any marked selectivity for either -adrenoceptor subtype. Compound XI and prenalterol were inactive as agonists and together with the partial agonists behaved as competitive antagonists to ISO in the two preparations. All drugs tested displaced [125I]CYP from -adrenoceptor sites, however, there was also a wide range of potency amongst the drugs.Analysis of the structure-affinity and structure-efficacy relationships indicated that removal of the 3-hydroxyl group from the catechol ring reduces both affinity and efficacy without altering the selectivity of the drug for either -adrenoceptor subtype. While aryloxypropanolamine derivatives have generally higher affinities than arylethanol-amines, especially at -adrenoceptor sites, their efficacies are generally reduced at both -adrenoceptors. The presence of a homoveratryl group in aryloxypropanolamines enhances slightly the affinity for 1- and reduces affinity for 2-adrenoceptors. With this amine group, efficacy is markedly reduced at 2- as opposed to 2-adrenoceptor sites.Thus for prenalterol, the small degree of cardioselectivity can be attributed to the oxymethylene group whilst its lack of agonist activity (i.e., efficacy) reflects a combined action of this group and the absence of the 3-hydroxyl group on the phenyl ring. In RO363 it can be deduced that the oxymethylene group, together with the homoveratryl substituent are responsible for the observed selective affinity of the drug for 1- as opposed to 2-adrenoceptors. 相似文献
85.
Conventional management of acute left sided colonic obstruction employs some form of proximal colostomy. Intraoperative antegrade colonic irrigation relieves proximal faecal loading and may permit safer primary resection and anastomosis. The results of a pilot study are presented, and are shown to be favourable.
on p.56
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相似文献86.
Low intakes of fruits and vegetables have resulted in suboptimal intakes of several micronutrients, including vitamin C. This cross-sectional study used data from 84,902 children/adults (≥1 y) who completed a 24-h dietary recall as part of the United States National Health and Nutrition Examination Survey (1999–2018). Mean vitamin C intakes from foods/beverages were calculated as were trends in major food/beverage sources of vitamin C. Percentages below the Estimated Average Requirement (EAR) were estimated. Overall, mean vitamin C consumption declined by 23% (97–75 mg/d; p-value for trend < 0.001). 100% fruit juice was the leading source of vitamin C (25.6% of total or 21.7mg/d), but this declined by 48% (25–13 mg/d; p-value for trend < 0.001). Whole fruit increased among children/adolescents (+75.8%;10–17 mg/d; p-value for trend < 0.001), but not adults, while the vegetable contribution was generally unchanged. The proportion of the population below the EAR increased by 23.8% on a relative scale or 9 percentage points on an absolute scale (38.3–47.4%). Declines in vitamin C intake is driven largely by decreases in fruit juice coupled with modest increases in whole fruit. Due to associations between vitamin C intake and numerous health outcomes these trends warrant careful monitoring moving forward. 相似文献
87.
Evelyn P. Murphy Christopher Fenelon Ahmed I. Akoud Stephen R. Kearns Fintan J. Shannon Colin G. Murphy 《The Journal of arthroplasty》2021,36(6):2044-2048
BackgroundUncemented hemiarthroplasty (UHA) for displaced femoral neck fracture (FNF) is favored by some surgeons because of the reduced rate of perioperative mortality and operative time. However higher rates of intraoperative and postoperative periprosthetic fractures (PPFs) have been reported. The aim of the study was to review day-0, day-1, day-2, day-30, and one-year mortality as well as intraoperative and postoperative PPF after UHA for displaced FNF and compare this with cemented hemiarthroplasties (CHAs) performed. Secondary objectives were to assess whether femoral stem geometry and alignment were associated with PPF in UHA.MethodsA retrospective observational study was conducted of patients treated with a hemiarthroplasty for a displaced FNF over an eleven-year period. Radiographic analysis was conducted of femoral geometry and stem alignment.ResultsOver the 11-year study period, 857 UHAs and 247 CHAs were performed. There were no on-table, day-0, day-1, or day-2 deaths in UHA. Intraoperative PPF occurred in 3.6% UHA and 2% CHA and postoperative PPF in 2.4% UHA and 4.8% CHA. Intraoperative PPF was not associated with increased mortality (P = .15), postoperative PPF, or all-cause revision in UHA. Valgus stem alignment was a risk factor for a postoperative PPF and additional surgery in UHA (P = .004).ConclusionUHA was associated with no perioperative deaths and a 30-day mortality rate of 5% in this series. It can be considered in patients with multiple medical comorbidities. Careful surgical planning and technique is important to optimize stem alignment particularly in Dorr C type femurs. 相似文献
88.
Sean Cowlishaw Olivia Metcalf Tracey Varker Caleb Stone Robyn Molyneaux Lisa Gibbs Karen Block Louise Harms Colin MacDougall H. Colin Gallagher Richard Bryant Ellie Lawrence‐Wood Connie Kellett Meaghan O'Donnell David Forbes 《Journal of traumatic stress》2021,34(1):46-55
Anger is an important dimension of affect and a prominent feature of posttraumatic mental health, but it is commonly overlooked in postdisaster settings. We aimed to examine the distribution and implications of significant anger problems in the aftermath of a natural disaster, via analyses of Beyond Bushfires survey data from 736 residents of rural communities 5 years after the 2009 Black Saturday bushfires in Victoria, Australia. Assessments included the five‐item Dimensions of Anger Reaction (DAR‐5) scale along with measures of PTSD, depression, and significant mental illness, and indicators of life satisfaction, suicidality, hostile aggressive behavior, and violence exposure. The results indicated that approximately 10% of respondents from areas highly affected by the bushfires scored above the provisional cutoff criteria for significant anger problems on the DAR‐5, which was a more than 3‐fold increase, OR = 3.26, relative to respondents from areas of low‐to‐moderate bushfire impact. The rates were higher among women, younger participants, and those who were unemployed, and co‐occurred commonly, although not exclusively, with other postdisaster mental health problems. Anger problems were also associated with lower life satisfaction, β = ?.31, an 8‐fold increase in suicidal ideation, OR = 8.68, and a nearly 13‐fold increase in hostile aggressive behavior, OR = 12.98. There were associations with anger problems and violence exposure, which were reduced when controlling for covariates, including probable PTSD. The findings provide evidence indicating that anger is a significant issue for postdisaster mental health and should be considered routinely alongside other posttraumatic mental health issues. 相似文献
89.
90.
Raoud Marayati Laura V. Bownes Colin H. Quinn Nikita Wadhwani Adele P. Williams Hooper R. Markert Venkatram Atigadda Jamie M. Aye Jerry E. Stewart Karina J. Yoon Elizabeth A. Beierle 《Journal of pediatric surgery》2021,56(6):1165-1173
IntroductionThe poor therapeutic efficacy seen with current treatments for neuroblastoma may be attributed to stem cell-like cancer cells (SCLCCs), a subpopulation of cancer cells associated with poor prognosis and disease recurrence. Retinoic acid (RA) is a differentiating agent used as maintenance therapy for high-risk neuroblastoma but nearly half of children treated with RA relapse. We hypothesized that 6-Methyl-UAB30 (6-Me), a second-generation rexinoid recently developed with a favorable toxicity profile compared to RA, would reduce cancer cell stemness in human neuroblastoma patient-derived xenografts (PDXs).MethodsCells from three neuroblastoma PDXs were treated with 6-Me and proliferation, viability, motility, and cell-cycle progression were assessed. CD133 expression, sphere formation, and mRNA abundance of stemness and differentiation markers were evaluated using flow cytometry, in vitro extreme limiting dilution analysis, and real-time PCR, respectively.ResultsTreatment with 6-Me decreased proliferation, viability, and motility, and induced cell-cycle arrest and differentiation in all three neuroblastoma PDXs. In addition, 6-Me treatment led to decreased CD133 expression, decreased sphere-forming ability, and decreased mRNA abundance of Oct4, Nanog, and Sox2, indicating decreased cancer cell stemness.Conclusions6-Me decreased oncogenicity and reduced cancer cell stemness of neuroblastoma PDXs, warranting further exploration of 6-Me as potential novel therapy for neuroblastoma. 相似文献