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61.
Apoptosis is an essential ubiquitous process that controls the duration of the life span of cells, thus playing a crucial role in morphogenetic, histogenetic, and phylogenetic developmental processes. Apaf1 (apoptosis protease activating factor 1) is one of the central mediators of the intrinsic apoptotic pathway and a part of the apoptosome, which activates procaspase-3 and promotes cell death. Gene knockout of Apaf1 in mice leads to late embryonic lethality with malformations such as the persistence of interdigital webs and hyperplasia of brain and retina. Therefore, Apaf1 is generally believed to play a crucial role in developmental apoptosis and have a widespread expression. However, its pattern of expression in early development remains unknown. To specify whether Apaf1 indeed plays this key role, we investigated the pattern of gene expression for Apaf1 in mouse embryos on day 7, 9, and 12 of development. Our results show, that gene expression for Apaf1 first occurs within the embryo between day 7 and 9 of development, becoming more widespread toward day 12 and then includes structures, such as yolk sac, mesenchyme, cartilage, heart anlage, otic vesicle, peridermis, and anlagen of the spinal ganglia and vertebral bodies. Our results also show that gene expression for Apaf1 is not ubiquitous in early mouse development. This finding indicates that cell death processes are independent of or less dependent on Apaf1 during this time. Of interest, an active gene expression for Apaf1 is also present in organ anlagen such as heart or intestine, in which no obvious phenotype is seen after Apaf1 deletion. This finding suggests a possible role for Apaf1 in such anlagen as a putative alternative compensatory pathway, which could be switched on in the case of defects in the mediators that are normally involved in such organs.  相似文献   
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Background  Stress gated myocardial perfusion single photon emission computed tomography (gSPECT) is increasingly used before and after intercurrent therapeutic intervention and is the basis for ongoing evaluation in the Department of Veterans Affairs clinical outcomes utilizing revascularization and aggressive drug evaluation (COURAGE) trial. Methods and Results  The COURAGE trial is a North American multicenter randomized clinical trial that enrolled 2287 patients to aggressive medical therapy vs percutaneous coronary intervention plus aggressive medical therapy. Three COURAGE nuclear substudies have been designed. The goals of substudy 0 are to examine the diagnostic accuracy of the extent and severity of inducible ischemia at baseline in COURAGE patients compared with patient symptoms and quantitative coronary angiography and to explore the relationship between inducible ischemia and the benefit from revascularization when added to medical therapy. Substudy 1 will correlate the extent and severity of provocative ischemia with the frequency, quality, and instability of recurrent symptoms in postcatheterization patients. Substudy 2 (n _ 300) will examine the usefulness of sequential gSPECT monitoring 6 to 18 months after therapeutic intervention. Together, these nuclear substudies will evaluate the role of gSPECT to determine the effectiveness of aggressive risk-factor modifications, lifestyle interventions, and anti-ischemic medical therapies with or without revascularization in reducing patients’ ischemic burdens. Conclusions  The unfolding of evidence on the application of gSPECT in trials such as COURAGE defines a new era for nuclear cardiology. We hope the evidence that emerges from the COURAGE trial will further establish the role of nuclear imaging in the evidence-based management of patients with stable coronary disease. The COURAGE trial was supported by the Cooperative Studies Program of the Department of Veterans Affairs Office of Research and Development in collaboration with the Canadian Institutes of Health Research. Unrestricted research grants were obtained from Merck & Co; Pfizer Pharmaceuticals; Bristol-Myers Squibb Medical Imaging; Astellas Pharma; Kos Pharmaceuticals; Data Scope; Astra Zeneca Pharmaceuticals; Astra-Zeneca-Canada; Schering-Plough Coorporation, Ltd; Sanofi-Aventis, Inc; First Horizon; and GE Healthcare. All industrial funding for this trial was directed through the Department of Veterans Affairs. Additional funding for this substudy was provided by grants to the Department of Veterans Affairs and Canadian Institutes of Health Research from Astellas Pharma and Bristol-Myers-Squibb Medical Imaging.  相似文献   
63.
Most of the techniques described in the literature for the repair of chronic partial ACL tears, don’t spare the intact portion of the ligament. The aim of this study was to perform a prospective analysis of the results of augmentation surgery using gracilis and semitendinosus tendons to treat partial sub-acute lesions of the ACL. This technique involves an “over the top” femoral passage, which enables salvage and strengthening of the intact portion of the ACL. The study included 47 patients treated consecutively at our institute from 1993 to 1998, with a mean injury-surgery interval of 18 weeks (range 12–36). The patients were followed up by clinical and instrumental assessment criteria at 3 months, 1 and 5 years after surgery. Clinical assessment was performed using the IKDC form. Subjective and functional parameters were assessed by the Tegner activity scale. Instrumental evaluation was done using the KT-2000 instrument: the 30-pound passive test and the manual maximum displacement test were performed. We obtained good or excellent results in 95.7% of cases. No recurrences in ligamentous laxity were observed. We believe that the described technique has the advantage of being compatible with ACL anatomy, and enables very rapid functional recovery.  相似文献   
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FDA’S Perspectives on Cardiovascular Devices   总被引:1,自引:0,他引:1  
The Food and Drug Administration (FDA) decision process for approving or clearing medical devices is often determined by a review of robust clinical data and extensive preclinical testing of the device. The mission statement for the Center for Devices and Radiological Health (CDRH) is to review the information provided by manufacturers so that it can promote and protect the health of the public by ensuring the safety and effectiveness of medical devices deemed appropriate for human use (Food, Drug & Cosmetic Act, §903(b)(1, 2(C)), December 31, 2004; accessed December 17, 2008 ). For high-risk devices, such as ventricular assist devices (VADs), mechanical heart valves, stents, cardiac resynchronization therapy (CRT) devices, pacemakers, and defibrillators, the determination is based on FDA’s review of extensive preclinical bench and animal testing followed by use of the device in a clinical trial in humans. These clinical trials allow the manufacturer to evaluate a device in the intended use population. FDA reviews the data from the clinical trial to determine if the device performed as predicted and the clinical benefits outweigh the risks. This article reviews the regulatory framework for different marketing applications related to cardiovascular devices and describes the process of obtaining approval to study a cardiovascular device in a U.S. clinical trial.  相似文献   
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The purpose of this study was to evaluate a single-session peer-led safer sex intervention, based on the Information-Motivation-Behavioral Skills theoretical model, for college students residing in campus residence halls. Participants (N = 108) were assigned to either an hour long control or 5-module intervention session. Compared to the control condition, the intervention increased participants’ information and women’s subjective norms about preventative behavior. Both the control and intervention sessions increased intentions to perform preventative behaviors (e.g., keep condoms available). These preliminary results suggest that this intervention is promising for increasing constructs associated with safer sexual behavior and could easily be implemented by residence hall staff.  相似文献   
69.
Aim and methods  Nutrition, unhealthy lifestyles and cancer appear to be strictly related, but few authors have analysed the interest in dietary information of cancer patients and their families. This survey was conducted in the Veneto area (Italy) to investigate the concern of cancer patients and their family members about diet as a health tool before and after diagnosis of cancer. Results  Seven hundred and four questionnaires were collected: 380 from cancer patients and 324 from family members of cancer subjects. Breast cancer (BC) was the most frequent disease for patients (61.8%) as well as families (26.5%). Generally, the importance of having precise diet information after diagnosis is recognised by 40.3% of patients, with significant differences between the various types of cancer: gastric and colon/rectum cancer (GCC) patients were more concerned than BC women about precise information concerning a diet to follow immediately after diagnosis (p = 0.000, ODs = 3.10, CI 1.68–5.71) or during treatments (p = 0.001, ODs = 2.67, CI 1.46–4.89). The nutritional information is supplied to patients in 34% of cases and to relatives in 30.3%, often from non-medical sources. In total healthcare workers (family doctor, oncologist, surgeon, dietician) represented the exclusive source of dietary information for 24.9% of patients and 22.9% of family members. Diet after diagnosis changes in 69.1% of GCC patients and in 39.2% of BC women. Relatives, particularly women, report difficulties preparing patients’ meals in 30.7% of cases, changes in the eating habits of the entire family in 29.9% and discontent connected with patients diet in 13.9%. The concern about proper nutrition after diagnosis increases more in GCC subjects (p < 0.025) when compared to BC subjects and in patients with more recent diagnosis (p < 0.041) when compared with patients with diagnosis >5 years ago, while in family members the interest in diet after diagnosis increases more in women than in men (p < 0.030) without other differences regarding the degree of relationship, type of cancer or diagnosis time. Relatives (92.7%) have more interest in nutritional education than patients (74.9%). Cancer patients <65 years were more interested in educational initiatives concerning nutrition (p = 0.000, ODs = 4.46, CI 2.6–7.4) than older patients (>65 years) and female subjects were more concerned than male patients (p = 0.008, ODs = 2.11, CI 1.2–3.6). Conclusions  The interest in the dietary knowledge and in educational initiatives concerning nutrition is high in cancer patients and their relatives, although it decreases with the age. The poor attention paid to nutrition of cancer patients by various healthcare workers deserves consideration, since the psychophysical wellbeing and perhaps also survival of cancer patients can be improved by correct dietary management, as well as, naturally, by the principal treatments themselves.  相似文献   
70.
BACKGROUND: The inflammatory cascade has been hypothesized to be an important mechanism of post-ischaemic myocardial reperfusion injury and several studies demonstrated that C1 esterase inhibitor (C1-INH) is effective in post-ischaemia myocardial protection. Therefore, we aimed to investigate prospectively in a randomised double-blind study the cardioprotective effects of C1-INH in ST segment elevation myocardial infarction (STEMI) in patients who underwent emergent reperfusion with coronary artery bypass grafting (CABG). METHODS: In this study, we enrolled 80 patients affected with STEMI who underwent emergent CABG. Patients were assigned in two groups (C1-INH group: receive 1000 UI of C1-INH; and placebo group: receive a saline solution). The effects of C1-INH on complement inhibition, myocardial cell injury extension and clinical outcome were studied. Haemodynamic data and myocardial function were monitored. C1-INH, C3a, C4a complement activation fragments and cardiac troponin I (cTnI) serum levels were measured before, during and after surgery. RESULTS: Patient characteristics were not different between the two groups. The overall in-hospital mortality rate was 6.2%. No statistical significant difference was observed between the two groups with regard to early mortality (p=0.36). Statistical significant difference between the two groups was showed for cardiopulmonary bypass support (p=0.04), administration of high dose of inotropes drugs (p=0.001), time of intubation (p=0.03), intensive care unit (ICU) stay (p=0.04) and in-hospital stay (p=0.03). A significant improvement in mean arterial pressure (p=0.03), cardiac index (p=0.02) and stroke volume (p=0.03) was showed in C1-INH group versus placebo group. The serum cTnI levels were significantly low in the C1-INH group versus placebo group after reperfusion, during the observation period. Plasma levels of C3a and C4a complement fragments were reduced significantly in C1-INH group. No drugs-related adverse effects were observed. CONCLUSIONS: The inhibition of the classic complement pathway by C1-INH appears to be an effective mean of preserving ischaemic myocardium from reperfusion injury as demonstrated by low serum cTnI levels in C1-INH group. Therefore, the use of C1-INH during CABG as a rescue therapy in STEMI patients is probably an effective treatment to inhibit complement activity and to improve cardiac function and haemodynamic performance without impacting early mortality. Large randomised study should be performed to support our results.  相似文献   
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