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1.
Intra-uterine immunization of mice with paternal allogeneic or xenogeneic (rat) splenocytes was found to increase embryo tolerance to cyclophosphamide (CP)-induced teratogenesis. As the CP-induced teratogenic effect was shown to be associated with apoptosis, the present study was designed to investigate whether the protective effect of immunopotentiation may be realized via an alteration of CP-induced apoptosis. Various doses of CP were injected intraperitoneally into ICR mice on day 12 of pregnancy. Intra-uterine immunization with xenogeneic rat splenocytes was carried out 3 weeks before mating. Implantation sites, resorptions, live and dead fetuses, as well as soft tissue anomalies and external malformations, were recorded to evaluate the CP-induced embryotoxic effect. In parallel, flow cytometric analysis and DNA fragmentation assay were used for evaluation of CP-induced apoptosis in limbs, tail and whole embryos. The treatment of mothers with a high dose of CP induced the death of almost all embryos and striking fetal growth retardation in survivors. This strong embryotoxic effect was accompanied by very prominent DNA degradation in cells collected from whole embryos. Immunostimulation caused a dramatic decrease of embryonal loss (by ˜ 50%) and a significant (about 30%) increase in fetal weight. Such an increase in fetal survival and in fetal weight was found to be accompanied by a clear decrease in apoptosis level in embryo cell populations as judged by DNA gel electrophoresis with subsequent quantitation of DNA fragmentation in negatives by an image analysis technique. After treatment with a low dose of CP, a decrease in the proportion of fetuses with limb and tail anomalies in immunized females was accompanied by a decrease in the proportion of apoptotic nuclei in cells taken from limbs and tails. The results of this study suggest that the teratogen-induced apoptosis may, at least partly, be dependent on fetomaternal immune interactions.  相似文献   
2.
Typical lesions of benign prostatic hyperplasia (BPH) were induced experimentally in the ventral prostate of adolescent (6 week old) male rats by citral, a nonsteroidal compound. Incipient BPH changes were already observed in the acinar glands 10 days after citral administration. A longer period of treatment (1 month) significantly enhanced epithelial hyperplasia, whereas the stromal elements were less reactive. Characteristic BPH lesions involving both prostatic compartments were found after 3 months of treatment. Castration prior to citral administration prevented such BPH changes; however, citral did not prevent the involutive lesions of castration. The mechanism of action of citral is yet unknown, various possibilities concerning the induction of BPH in rats are presented and discussed. The potential advantage of this model, especially as BPH is not necessarily linked to age or exogenous hormones, may offer new alternative pathways for understanding the complexity of BPH pathogenesis in animals and perhaps even in man.  相似文献   
3.
Individuals with phenylketonuria (PKU) have been reported to have altered trace mineral status. In this study, we evaluated in a murine PKU model whether protein level and level of phenylalanine (PHE) restriction could modulate iron, copper, and zinc status. Fifty-four male weanling PKU and control mice were assigned to receive for 56 days an elemental low or normal protein diet; PKU mice also were assigned to receive PHE restriction (treated) or no restriction (untreated). PHE-restricted mice consumed a prescribed dietary PHE to maintain plasma PHE concentrations between 120 and 480 micromol/L. PHE-unrestricted and control mice received equal amounts of dietary PHE. Intestinal and hepatic copper, iron, and zinc were measured at day 56 and fecal minerals measured at baseline and day 56. Mean plasma PHE concentrations were significantly greater in PKU PHE-unrestricted versus PKU PHE-restricted mice and control mice. Mean intestinal weights when normalized for body weight were significantly greater in PKU mice versus control mice. PKU PHE-unrestricted mice had significantly lower hepatic copper and zinc than PKU PHE-restricted mice, and significantly greater hepatic iron than control and PKU PHE-restricted mice. PKU PHE-unrestricted mice on a low protein diet had hepatic iron concentrations about 1.5 times that of the other mice. Fecal iron concentrations in all mice were significantly greater at day 56 than at baseline. No animal group effects or protein level effects were found for fecal copper, iron, or zinc contents. We conclude that hyperphenylalaninemia alters the metabolism of iron, copper, and zinc in PKU mice.  相似文献   
4.
From the beginning, the reporting of the results of National Acute Spinal Cord Injury Studies (NASCIS) II and III has been incomplete, leaving clinicians in the spinal cord injury (SCI) community to use or avoid using methylprednisolone in acute SCI on the basis of faith rather than a publicly developed scientific consensus. NASCIS II was initially reported by National Institutes of Health announcements, National Institutes of Health facsimiles to emergency room physicians, and the news media. The subsequent report in the New England Journal of Medicine implied that there was a positive result in the primary efficacy analysis for the entire 487 patient sample. However, this analysis was in fact negative, and the positive result was found only in a secondary analysis of the subgroup of patients who received treatment within 8 hours. In addition, that subgroup apparently had only 62 patients taking methylprednisolone and 67 receiving placebo. The NASCIS II and III reports embody specific choices of statistical methods that have strongly shaped the reporting of results but have not been adequately challenged or or even explained. These studies show statistical artifacts that call their results into question. In NASCIS II, the placebo group treated before 8 hours did poorly, not only when compared with the methylprednisolone group treated before 8 hours but even when compared with the placebo group treated after 8 hours. Thus, the positive result may have been caused by a weakness in the control group rather than any strength of methylprednisolone. In NASCIS III, a randomization imbalance occurred that allocated a disproportionate number of patients with no motor deficit (and therefore no chance for recovery) to the lower dose control group. When this imbalance is controlled for, much of the superiority of the higher dose group seems to disappear. The NASCIS group's decision to admit persons with minor SCIs with minimal or no motor deficit not only enables statistical artifacts it complicates the interpretation of results from the population actually sampled. Perhaps one half of the NASCIS III sample may have had at most a minor deficit. Thus, we do not know whether the results of these studies reflect the severely injured population to which they have been applied. The numbers, tables, and figures in the published reports are scant and are inconsistently defined, making it impossible even for professional statisticians to duplicate the analyses, to guess the effect of changes in assumptions, or to supply the missing parts of the picture. Nonetheless, even 9 years after NASCIS II, the primary data have not been made public. The reporting of the NASCIS studies has fallen far short of the guidelines of the ICH/FDA and of the Evidence-based Medicine Group. Despite the lucrative "off label" markets for methylprednisolone in SCI, no Food and Drug Association indication has been obtained. There has been no public process of validation. These shortcomings have denied physicians the chance to use confidently a drug that many were enthusiastic about and has left them in an intolerably ambiguous position in their therapeutic choices, in their legal exposure, and in their ability to perform further research to help their patients.  相似文献   
5.
The aim of this article is to provide clarity of the concept of health habit. Using Walker and Avant's (1983; 2010) method for conducting a concept analysis, the authors identify the attributes and characteristics of health habit, its theoretical and practical application to nursing, and sample cases to further illustrate the concept. Empirical and conceptual literature was used to inform this concept analysis. Articles and one book from 1977 to 2014 were reviewed from PsycINFO, Medline, Cumulative Index to Nursing Health Literature (CINAHL), Science Direct, EBSCOhost and Web of Science. Offering a clear definition and conceptual model of health habit provide the foundation to identify/develop appropriate measures of the concept and guide further investigation of understanding the development and sustainability of healthy habits. Additional research is needed to test the conceptual relationships between health habits and outcome variables as they apply to different groups across the age continuum.  相似文献   
6.
Bovine granulosa cells seeded in the presence of serum on extracellular matrix-coated dishes proliferate actively when exposed to serum-free medium supplemented with insulin (2 microgram/ml), fibroblast growth factor (FGF, 100 ng/ml), and high density lipoprotein (HDL, 30 microgram protein/ml). The final density of the cultures is 80-120% that of cultures grown in the presence of medium supplemented with optimal concentration (10%) of calf serum. Insulin has the greatest effect on cell proliferation when added alone to serum-free medium, since it induced an increase in cell number that was 35-60% that observed with optimal serum concentration. Somatomedin C can replace insulin when added alone. FGF, epidermal growth factor, or HDL had no significant effect on cell proliferation by themselves. When these factors were added together with insulin, they acted synergistically in stimulating cell proliferation. When cultures were seeded in the total absence of serum, the addition of transferrin (10 microgram/ml) to serum-free medium was required in order for insulin and FGF to be mitogenic. Cultures maintained on extracellular matrix and exposed to serum-free medium alone have a lifespan in culture of 4 generations. Addition of insulin, FGF, and HDL increases the lifespan of the cultures to 12 generations. Bovine granulosa cells, which proliferate in a defined medium, respond to dibutyryl cAMP by releasing progesterone into the medium. Addition of FSH to the defined medium resulted in a 30% decrease in cell proliferation and in a 2.1-fold increase in the amount of progesterone released into the medium in response to dibutyryl cAMP. This release of progesterone reached a level similar to that observed with cultures grown in medium supplemented with optimal concentration of serum and exposed or not to FSH during their growth phase and at confluence. These results demonstrate that bovine granulosa cells can actively proliferate in a serum-free medium and maintain their differentiated function, as indicated by their ability to produce progesterone.  相似文献   
7.
Rat stromal bone-marrow cells cultured in the presence of dexamethasone, ascorbic acid, &#103 -glycerophosphate, and fibroblast growth factor-2 (FGF-2) express the osteogenic phenotype (Pitaru et al., J. Bone Miner. Res . 8:919-929, 1993). The purpose of this study was to establish a long-term homogeneous culture expressing the osteogenic phenotype. The cultures were routinely passaged every 5 days in the absence or presence of either or both dexamethasone and FGF-2, and the cumulative doubling number and the expression of the osteogenic phenotype were determined. Cultures treated with dexamethasone (10 &#109 7 M) ceased proliferation and only upon addition of FGF-2 (3 ng/ml) was a spontaneous immortalization achieved, as expressed by sustained proliferation for about 1 year, with a doubling time of 22 h and more than 300 doublings in 72 passages. Both FGF-2 and dexamethasone are required and act synergistically to maintain cell propagation, alkaline phosphatase expression, and osteocalcin secretion; however, protein content was FGF-2 dependent and the mineralization was dexamethasone dependent. Repetitive single-cell cloning tested the homogeneity and stability of the cells expressing the osteogenic phenotype in these long-term cultures. It was shown that 25% to 50% of subclones derived from clones with an osteogenic phenotype do not further express the osteogenic phenotype. In conclusion, we have established a spontaneously immortalized dexamethasone- and FGF-2-dependent rat stromal bone-marrow-derived long-term culture expressing the osteogenic phenotype. The cultures tend to lose the osteogenic phenotype, and dexamethasone supports the long-term preservation of the osteogenic phenotype.  相似文献   
8.
9.
Antithrombotic management of patients with atrial fibrillation (AF) undergoing coronary stenting is complicated by the need for anticoagulant therapy for stroke prevention and dual antiplatelet therapy for prevention of stent thrombosis and coronary events. Triple antithrombotic therapy, typically comprising warfarin, aspirin, and clopidogrel, is associated with a high risk of bleeding. A modest‐sized trial of oral anticoagulation with warfarin and clopidogrel without aspirin showed improvements in both bleeding and thrombotic events compared with triple therapy, but large trials are lacking. The RE‐DUAL PCI trial (NCT 02164864) is a phase 3b, a strategy of prospective, randomized, open‐label, blinded‐endpoint trial. The main objective is to evaluate dual antithrombotic therapy with dabigatran etexilate (110 or 150 mg twice daily) and a P2Y12 inhibitor (either clopidogrel or ticagrelor) compared with triple antithrombotic therapy with warfarin, a P2Y12 inhibitor (either clopidogrel or ticagrelor, and low‐dose aspirin (for 1 or 3 months, depending on stent type) in nonvalvular AF patients who have undergone percutaneous coronary intervention with stenting. The primary endpoint is time to first International Society of Thrombosis and Hemostasis major bleeding event or clinically relevant nonmajor bleeding event. Secondary endpoints are the composite of all cause death or thrombotic events (myocardial infarction, or stroke/systemic embolism) and unplanned revascularization; death or thrombotic events; individual outcome events; death, myocardial infarction, or stroke; and unplanned revascularization. A hierarchical procedure for multiple testing will be used. The plan is to randomize ~ 2500 patients at approximately 550 centers worldwide to try to identify new treatment strategies for this patient population.  相似文献   
10.
Composite endpoints are commonly used as the primary measure of efficacy in heart failure clinical trials to assess the overall treatment effect and to increase the efficiency of trials. Clinical trials still must enrol large numbers of patients to accrue a sufficient number of outcome events and have adequate power to draw conclusions about the efficacy and safety of new treatments for heart failure. Additionally, the societal and health system perspectives on heart failure have raised interest in ascertaining the effects of therapy on outcomes such as repeat hospitalization and the patient's burden of disease. Thus, novel methods for using composite endpoints in clinical trials (e.g. clinical status composite endpoints, recurrent event analyses) are being applied in current and planned trials. Endpoints that measure functional status or reflect the patient experience are important but used cautiously because heart failure treatments may improve function yet have adverse effects on mortality. This paper discusses the use of traditional and new composite endpoints, identifies qualities of robust composites, and outlines opportunities for future research.  相似文献   
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