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A single myocardial stretch or decreased systolic fiber shortening stimulates the expression of heat shock protein 70 in the isolated, erythrocyte-perfused rabbit heart. 总被引:9,自引:3,他引:6 下载免费PDF全文
A A Knowlton F R Eberli P Brecher G M Romo A Owen C S Apstein 《The Journal of clinical investigation》1991,88(6):2018-2025
The regulation of heat shock protein 70 (HSP 70) expression was examined in the isolated, red blood cell-perfused rabbit heart by Northern and Western blot analysis. In the isovolumic (balloon in left ventricle), isolated perfused heart, HSP 70 mRNA was increased threefold after 30 min and sevenfold at 2 and 4 h compared to normal, nonperfused hearts. To further elucidate the etiology of the increase in HSP 70 mRNA, the effects of decreased systolic shortening (isovolumic heart) and of a single ventricular stretch were examined. Perfusion without the application of a stretch or the presence of a balloon resulted in no increase in HSP 70 mRNA; while a single stretch resulted in a threefold increase in HSP 70 mRNA. These changes were accompanied by an increase in HSP 70 protein by Western blot analysis. To elucidate the signalling mechanism mediating the increase in HSP 70, hearts were perfused with H7, a protein kinase C inhibitor. H7 did not prevent the induction of HSP 70. These results indicate that initiation of expression of myocardial HSP 70 can be stimulated by a single myocardial stretch or by prevention of systolic shortening. These mechanisms may contribute to the rapid expression of HSP 70 after coronary occlusion when dyskinesis, reduced systolic shortening, and increased diastolic segment length all occur. 相似文献
34.
Penny H Feldman Christopher M Murtaugh Liliana E Pezzin Margaret V McDonald Timothy R Peng 《Health services research》2005,40(3):865-886
OBJECTIVE: To assess the impact and cost-effectiveness of two information-based provider reminder interventions designed to improve self-care management and outcomes of heart failure (HF) patients. DATA SOURCES/STUDY SETTING: Interview and agency administrative data on 628 home care patients with a primary diagnosis of HF. STUDY DESIGN: Patients were treated by nurses randomly assigned to usual care or one of two intervention groups. The basic intervention was an e-mail to the patient's nurse highlighting six HF-specific clinical recommendations. The augmented intervention supplemented the initial nurse reminder with additional clinician and patient resources. DATA COLLECTION: Patient interviews were conducted 45 days post admission to measure self-management behaviors, HF-specific outcomes (Kansas City Cardiomyopathy Questionnaire-KCCQ), health-related quality of life (EuroQoL), and service use. PRINCIPAL FINDINGS: Both interventions improved the mean KCCQ summary score (15.3 and 12.9 percent, respectively) relative to usual care (p< or =.05). The basic intervention also yielded a higher EuroQoL score relative to usual care (p< or =.05). In addition, the interventions had a positive impact on medication knowledge, diet, and weight monitoring. The basic intervention was more cost-effective than the augmented intervention in improving clinical outcomes. CONCLUSIONS: This study demonstrates the positive impact of targeting evidence-based computer reminders to home health nurses to improve patient self-care behaviors, knowledge, and clinical outcomes. It also advances the field's limited understanding of the cost-effectiveness of selected strategies for translating research into practice. 相似文献
35.
Integrating Decision Making and Mental Health Interventions Research: Research Directions 总被引:2,自引:0,他引:2
The importance of incorporating patient and provider decision-making processes is in the forefront of the National Institute of Mental Health (NIMH) agenda for improving mental health interventions and services. Key concepts in patient decision making are highlighted within a simplified model of patient decision making that links patient-level/"micro" variables to services-level/"macro" variables via the decision-making process that is a target for interventions. The prospective agenda for incorporating decision-making concepts in mental health research includes (a) improved measures for characterizing decision-making processes that are matched to study populations, complexity, and types of decision making; (b) testing decision aids in effectiveness research for diverse populations and clinical settings; and (c) improving the understanding and incorporation of preference concepts in enhanced intervention designs. 相似文献
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Rapid prototype patient-specific drill template for cervical pedicle screw placement. 总被引:11,自引:0,他引:11
Brent D Owen Gary E Christensen Joseph M Reinhardt Timothy C Ryken 《Computer aided surgery》2007,12(5):303-308
OBJECTIVE: To assess the feasibility and accuracy of a drill template for the placement of a cervical pedicle screw in a single vertebral level. MATERIALS AND METHODS: A volumetric CT scan was performed on a cadaver cervical spine. Using computer software, a drill template with a predefined trajectory was constructed that was designed to match the posterior surface of the right side of the fifth cervical vertebra. A physical template was created from the computer model using a rapid prototyping machine. The drill template was used to guide drilling of a pilot hole, and a CT scan was performed to assess the accuracy of this hole. A 3.5-mm diameter pedicle screw was placed in the pilot hole. The spine was then dissected to separate the vertebrae and the trajectory of the screw was visually inspected. RESULTS: The feasibility of this patient-specific rapid prototyping technique was demonstrated. Imaging and visual inspection confirmed accurate placement of the pilot hole and cervical pedicle screw without cortical violation. CONCLUSIONS: The potential use of drill templates to place cervical pedicle screws is promising. Our initial methodology appears to provide an accurate technique and trajectory for pedicle screw placement in the cervical spine. 相似文献
39.
Philip F. Giampietro MD PhD Margaret G. E. Peterson PhD Robert Schneider MD Jessica G. Davis MD Stephen W. Burke MD Oheneba Boachie-Adjei MD Charles M. Mueller PhD RD Cathleen L. Raggio MD 《HSS journal》2007,3(1):89-92
Reduced bone mineral density (BMD) was sporadically reported in patients with Marfan syndrome. This may or may not place the
Marfan patient at increased risk for bone fracture. In comparing the BMDs of our patients with those reported in the literature,
it seemed that agreement between values, and hence the degree of osteoporosis or osteopenia reported, was dependent on the
instrumentation used. The objective of this study was to statistically assess this impression. Bone mineral density measurements
from our previously published study of 30 adults with Marfan syndrome performed on a Lunar DPXL machine were compared with
studies published between 1993–2000 measured using either Lunar or Hologic bone densitometry instruments. The differences
of our measurements compared with those made on other Lunar machines were not statistically significant, but did differ significantly
with published results from Hologic machines (P < 0.001). Before progress can be made in the assessment of BMD and fracture risk in Marfan patients and in the evidence-based
orthopedic management of these patients, standardization of instrumental bone density determinations will be required along
with considerations of height, obesity, age, and sex. 相似文献
40.
Gina Kearney MSN RN CS AHN-BC JeMe Cioppa-Mosca PT MBA Margaret G. E. Peterson Ph.D C. Ronald MacKenzie MD 《HSS journal》2007,3(2):198-201
In an outpatient rehabilitation setting, both patients’ use and therapists’ knowledge of complementary and alternative medicine
(CAM) varies widely. Based on this observation and a recognition of CAM as an emerging practice area for rehabilitation professionals,
it was felt that a thorough and consistent approach to the education and orientation of physical therapists to the world of
CAM and integrative care was needed. This special interest paper will describe one center’s approach, development, and use
of a unique and comprehensive training manual designed to provide both a structured and standardized approach for educating
physical therapists about CAM and related therapeutic modalities. This innovative teaching tool allows for multiple methods
of content delivery within a multidisciplinary format and can be used for those who practice currently or desire to practice
in an integrative care environment. 相似文献