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31.
32.

Background

Aortic pulse wave velocity (PWV) was linked to LV-geometry and -function in patients with kidney disease and non-ischemic cardiomyopathy. The role of aortic compliance after acute STEMI is so far unknown. In the present study, we prospectively investigated the relationship of increased aortic stiffness with biomarkers of myocardial wall stress 4 months after STEMI.

Methods

48 STEMI patients who were reperfused by primary coronary angioplasty underwent cardiovascular magnetic resonance (CMR) at baseline and at 4-month follow-up. The CMR protocol comprised cine-CMR as well as gadolinium contrast-enhanced CMR. Aortic PWV was determined by velocity-encoded, phase-contrast CMR. Blood samples were routinely drawn at baseline and follow-up to determine N-terminal pro-B-type natriuretic peptide (NT-proBNP). In a subgroup of patients, mid-regional pro-adrenomedullin (MR-proADM) and mid-regional pro-A-type natriuretic peptide (MR-proANP) levels were determined.

Results

Patients with a PWV above median (> 7.0 m/s) had significantly higher NT-proBNP, MR-proADM and MR-proANP concentrations at 4-month follow-up than patients with a PWV below median (all p < 0.02). PWV showed moderate to good correlation with NT-proBNP, MR-proAMD and MR-proANP levels 4 months after STEMI (all p < 0.05). Multivariate analysis revealed PWV, beside myocardial infarct size, as an independent predictor of 4-month NT-proBNP levels after correction for age, creatinine and LV ejection fraction (model r: 0.781, p < 0.001).

Conclusion

Aortic stiffness is directly associated with biomarkers of myocardial wall stress 4 months after reperfused STEMI, suggesting a role for aortic stiffness in chronic LV-remodelling.  相似文献   
33.
Neuroradiology - In this study, we aimed to develop a novel prediction model to identify patients in need of a non-contrast head CT exam during emergency department (ED) triage. We collected data...  相似文献   
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35.
We have assessed the ability of skeletal myoblasts to form long-term, differentiated grafts in ventricular myocardium. C2C12 myoblasts were grafted directly into the heart of syngeneic mice. Viable grafts were observed as long as 3 mo after implantation. Immunohistological analyses revealed the presence of differentiated myotubes that stably expressed the skeletal myosin heavy chain isoform. Thymidine uptake studies indicated that virtually all of the grafted skeletal myocytes were withdrawn from the cell cycle by 14 d after grafting. Graft myocytes exhibited ultrastructural characteristics typical of differentiated myotubes. Graft formation and the associated myocardial remodeling did not induce overt cardiac arrhythmia. This study indicates that the myocardium can serve as a stable platform for skeletal myoblast grafts. The long-term survival, differentiated phenotype, and absence of sustained proliferative activity observed in myoblast grafts raise the possibility that similar grafting approaches may be used to replace diseased myocardium. Furthermore, the genetic tractability of myoblasts could provide a useful means for the local delivery of recombinant molecules to the heart.  相似文献   
36.
Negative pressure wound therapy (NPWT) has become the prevailing standard of care for treating complex soft tissue wounds and is now being considered for use in alternative applications including improving skin graft take. While it is generally agreed that negative pressure leads to improved wound healing, universal consensus on its optimal application is not supported in the literature. We describe the design and validation of a bioreactor to determine the prospective benefits of NPWT on skin grafts and engineered skin substitutes (ESS). Clinically relevant pressures were applied, and the native human skin was able to withstand greater negative pressures than the engineered substitutes. Both skin types were cultured under static, flow‐only, and −75 mm Hg conditions for 3 days. While it remained intact, there was damage to the epidermal‐dermal junction in the ESS after application of negative pressure. The normal skin remained viable under all culture conditions. The engineered skin underwent apoptosis in the flow‐only group; however, the application of negative pressure reduced apoptosis. Vascular endothelial growth factor levels were significantly higher in the normal flow‐only group, 152.0 ± 75.1 pg/mg protein, than the other culture conditions, 81.6 ± 35.5 pg/mg for the static and 103.6 ± pg/mg for the negative pressure conditions. The engineered skin had a similar trend but the differences were not significant. This bioreactor design can be used to evaluate the impacts of NPWT on the anatomy and physiology of skin to improve outcomes in wounds after grafting with normal or engineered skin.  相似文献   
37.
This study is the first to provide an extensive overview of the microbiology of acute ear, nose and throat infections requiring hospitalisation. All 2,028 cases of acute infections admitted between 1 January 2001 and 31 December 2006 were reviewed to assess the use of pre-admission antibiotics, microbiological results, antibiotic and surgical management and length of hospitalisation. Infections of the oropharynx accounted for the vast majority of admissions, followed by ear infections, and cutaneous neck abscesses. Peritonsillar abscess was the most frequent diagnosis, accounting for over one third of admissions (39.8%, 808 out of 2,028). Complete microbiological data were available for 1,430 cultures, and were analysed for trends with respect to diagnosis, age, gender and use of pre-admission antibiotics. Forty-six percent (657 out of 1,430) of cultures yielded no growth or normal flora. This value increased to 77.0% (298 out of 387) in patients with pre-admission antibiotics. The distribution of microbiological isolates varied significantly between patients with and without pre-admission antibiotics, as well as with respect to age and gender. The most frequently isolated bacteria were Group A Streptococcus (13.7%, 196 out of 1,430), Fusobacterium necrophorum (13.6%, 195 out of 1,428) and Staphylococcus aureus (8.0%, 114 out of 1,430). Fusobacterium necrophorum was primarily isolated from cases of peritonsillar abscess (90.8%, 177 out of 195). This study suggests that F. necrophorum is a far more widespread pathogen in otorhinolaryngology than previously reported, and questions the value of routine culturing, as results rarely altered initial treatment. Further research on the microbiological variations with age and gender is recommended to better target culturing and treatment, and enhance our understanding of the pathogenesis of ear, nose and throat infections.  相似文献   
38.
In this study, the temperature profiles of insulin pump reservoirs during normal wear conditions across multiple seasons were characterized. Thermocouples secured in reservoirs filled with insulin diluent were loaded in infusion pumps worn by volunteers. Reservoir and ambient environmental temperature data and activity levels were logged during the course of normal daily activities in February (winter), April (spring), and August (summer). Each seasonal data set comprised 7 to 14 days of wear from 3 to 5 volunteers. Reservoir temperature profiles were generally higher than ambient temperatures, likely due to heat transfer from the wearer when the pump was placed close to the body. Temperature conditions inside pump reservoirs fluctuated between 25°C and 37°C regardless of seasonal variations. The average reservoir temperature remained close to 30°C across all seasons, notably lower than used in previously published compatibility and stability protocols (37°C). Results from this study could be utilized to develop more accurate stability and compatibility testing procedures for new insulin formulations and/or delivery devices.  相似文献   
39.
In a prospective multi-institutional study of 384 patients undergoing endoscopy, an 8.9% incidence of second primary neoplasms was discovered simultaneously in the lung (3.3%), esophagus (1.8%), and other head and neck sites (3.6%). The endoscopy was the only source of detection of these tumors in 58% of cases. A trend indicates that flexible fiberoptic bronchoscopy was more effective than rigid bronchoscopy in discovering lung tumors (7.5% vs 2.3%). Nevertheless, the chest roentgenogram remains an important tool in the diagnosis of second primary lesions in the lung. Panendoscopy is safe, takes little time, and can add invaluable information concerning therapy in patients with head and neck cancers.  相似文献   
40.
An immunoradiometric assay with the use of a monoclonal antibody can detect an antigenic determinant (CA125) in peripheral blood from more than 80% of patients with epithelial ovarian cancer. In this report elevated levels of CA125 were detected in serum from patients with adenocarcinomas of the fallopian tube, endometrium, and endocervix. Among patients with endometrial cancer, CA125 levels were elevated in recurrent or disseminated disease but not with tumors confined to the uterus.  相似文献   
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