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21.
A technique of modelling the left ventricle for the purpose of volume determination has been devised. Two-dimensional echocardiographic data from the apical four chamber and two chamber views are used to pattern the ventricle as a stack of elliptical discs. The method has been validated for an array of regular geometric shapes commonly associated with ventricular architecture. The relative advantages of this model are discussed. 相似文献
22.
Two-dimensional echocardiographic imaging of the mitral valve orifice was attempted in 26 patients with isolated mitral stenosis. The intention was to examine further the clinical usefulness and limitations of this technique for estimating the severity of mitral stenosis. Technically adequate recordings of the mitral orifice were obtained in 20 patients (77%). Mitral valve area calculated from echocardiography compared favorably to the valve area derived from cardiac catheterization with the use of the Gorlin formula (r = 0.95). The average difference between the two methods was 0.109 cm(2). Two-dimensional echocardiography does provide clinically useful data for predicting the degree of mitral stenosis in the majority of patients provided that critical technical limitations are recognized. 相似文献
23.
Cortés JC Montalvo EA Muñiz J Mornet D Garrido E Centeno F Cisneros B 《Neurochemical research》2009,34(3):438-444
Previously, it was shown that Dp71f binds to the β1-integrin adhesion complex to modulate PC12 cell adhesion. The absence
of Dp71f led to a failure in the β1-integrin adhesion complex formation. One of the structural proteins which links the β1-integrin
cytoplasmic domain to the actin cytoskeleton is ILK. GSK3-β is an ILK substrate and the carboxi-terminal region of dystrophin
427 is a substrate for hierarchical phosphorylation by GSK3-β. Dp71f contains the carboxi-terminal domain present in dystrophin
427. By using co-immunoprecipitation assays, in the present work it is demonstrated that in the neuronal PC12 cell line an
interaction between Dp71f and GSK3-β occurs. This interaction was corroborated by in vitro pulldown assays. We show that GSK3-β
is recruited to the β1-integrin complex and that a reduced expression of Dp71f induces a reduced GSK3-β recruitment to the
β1-integrin complex. In addition, the present work establishes that adhesion of PC12 cells to laminin does not influence the
phosphorylation status of Dp71f. 相似文献
24.
Neira R Arroyave J Ramirez H Ortiz CL Solarte E Sequeda F Gutierrez MI 《Plastic and reconstructive surgery》2002,110(3):912-22; discussion 923-5
Low-level laser energy has been increasingly used in the treatment of a broad range of conditions and has improved wound healing, reduced edema, and relieved pain of various etiologies. This study examined whether 635-nm low-level lasers had an effect on adipose tissue in vivo and the procedural implementation of lipoplasty/liposuction techniques. The experiment investigated the effect of 635-nm, 10-mW diode laser radiation with exclusive energy dispersing optics. Total energy values of 1.2 J/cm(2), 2.4 J/cm(2), and 3.6 J/cm(2) were applied on human adipose tissue taken from lipectomy samples of 12 healthy women. The tissue samples were irradiated for 0, 2, 4, and 6 minutes with and without tumescent solution and were studied using the protocols of transmission electron microscopy and scanning electron microscopy. Nonirradiated tissue samples were taken for reference. More than 180 images were recorded and professionally evaluated. All microscopic results showed that without laser exposure the normal adipose tissue appeared as a grape-shaped node. After 4 minutes of laser exposure, 80 percent of the fat was released from the adipose cells; at 6 minutes of laser exposure, 99 percent of the fat was released from the adipocyte. The released fat was collected in the interstitial space. Transmission electron microscopic images of the adipose tissue taken at x60,000 showed a transitory pore and complete deflation of the adipocytes. The low-level laser energy affected the adipose cell by causing a transitory pore in the cell membrane to open, which permitted the fat content to go from inside to outside the cell. The cells in the interstitial space and the capillaries remained intact. Low-level laser-assisted lipoplasty has a significant impact on the procedural implementation of lipoplasty techniques. 相似文献
25.
A large pulmonary arteriovenous fistula was discovered in a patient with long-standing cyanosis, clubbing and dyspnea, with no other cardiovascular signs or symptoms and a normal chest roentgenogram at the time of cardiac catheterization and pulmonary angiography. The fistula was overshadowed by the cardiac silhouette. Surgical resection was successful. Although rarely undetected on the chest roentgenogram, this potentially lethal malformation should be considered in the differential diagnosis of cyanosis unaccompanied by other cardiovascular signs or symptoms. 相似文献
26.
The submandibular glands of male C57BL/6J mice were studied cytologically and chemically at the following ages (months): 1–1.5, 6–8, 12–13, 28–32. The relative proportion of granular convoluted tubules (GCT) as well as the size and content of secretion granules of GCT cells, progressively increased throughout the first year of life. Correspondingly, the concentration within the glands of two GCT cell products, epidermal growth factor (EGF) and protease, also steadily increased. In senescent glands, GCTs formed relatively less of the gland parenchyma and were composed of shorter cells with reduced amounts of secretory granules. The concentration of EGF was reduced to 17% of its peak value at one year, while protease activity declined to 50% of its peak value. These morphologic and chemical findings imply a functional impairment in submandibular glands of the mouse with senescence. 相似文献
27.
Anna M. Stewart Ibarra Sadie J. Ryan Efrain Beltrán Raúl Mejía Mercy Silva ángel Mu?oz 《PloS one》2013,8(11)
Background
Dengue fever, a mosquito-borne viral disease, is now the fastest spreading tropical disease globally. Previous studies indicate that climate and human behavior interact to influence dengue virus and vector (Aedes aegypti) population dynamics; however, the relative effects of these variables depends on local ecology and social context. We investigated the roles of climate and socio-ecological factors on Ae. aegypti population dynamics in Machala, a city in southern coastal Ecuador where dengue is hyper-endemic.Methods/Principal findings
We studied two proximate urban localities where we monitored weekly Ae. aegypti oviposition activity (Nov. 2010-June 2011), conducted seasonal pupal surveys, and surveyed household to identify dengue risk factors. The results of this study provide evidence that Ae. aegypti population dynamics are influenced by social risk factors that vary by season and lagged climate variables that vary by locality. Best-fit models to predict the presence of Ae. aegypti pupae included parameters for household water storage practices, access to piped water, the number of households per property, condition of the house and patio, and knowledge and perceptions of dengue. Rainfall and minimum temperature were significant predictors of oviposition activity, although the effect of rainfall varied by locality due to differences in types of water storage containers.Conclusions
These results indicate the potential to reduce the burden of dengue in this region by conducting focused vector control interventions that target high-risk households and containers in each season and by developing predictive models using climate and non-climate information. These findings provide the region''s public health sector with key information for conducting time and location-specific vector control campaigns, and highlight the importance of local socio-ecological studies to understand dengue dynamics. See Text S1 for an executive summary in Spanish. 相似文献28.
Marina Stolina Georg Schett Denise Dwyer Steven Vonderfecht Scot Middleton Diane Duryea Efrain Pacheco Gwyneth Van Brad Bolon Ulrich Feige Debra Zack Paul Kostenuik 《Arthritis research & therapy》2009,11(6):1-15
Introduction
Rat adjuvant-induced arthritis (AIA) and collagen-induced arthritis (CIA) feature bone loss and systemic increases in TNFα, IL-1β, and receptor activator of NF-κB ligand (RANKL). Anti-IL-1 or anti-TNFα therapies consistently reduce inflammation in these models, but systemic bone loss often persists. RANKL inhibition consistently prevents bone loss in both models without reducing joint inflammation. Effects of these therapies on systemic markers of bone turnover and inflammation have not been directly compared.Methods
Lewis rats with established AIA or CIA were treated for 10 days (from day 4 post onset) with either PBS (Veh), TNFα inhibitor (pegsunercept), IL-1 inhibitor (anakinra), or RANKL inhibitor (osteoprotegerin (OPG)-Fc). Local inflammation was evaluated by monitoring hind paw swelling. Bone mineral density (BMD) of paws and lumbar vertebrae was assessed by dual X-ray absorptiometry. Markers and mediators of bone resorption (RANKL, tartrate-resistant acid phosphatase 5b (TRACP 5B)) and inflammation (prostaglandin E2 (PGE2), acute-phase protein alpha-1-acid glycoprotein (α1AGP), multiple cytokines) were measured in serum (day 14 post onset).Results
Arthritis progression significantly increased paw swelling and ankle and vertebral BMD loss. Anti-TNFα reduced paw swelling in both models, and reduced ankle BMD loss in AIA rats. Anti-IL-1 decreased paw swelling in CIA rats, and reduced ankle BMD loss in both models. Anti-TNFα and anti-IL-1 failed to prevent vertebral BMD loss in either model. OPG-Fc reduced BMD loss in ankles and vertebrae in both models, but had no effect on paw swelling. Serum RANKL was elevated in AIA-Veh and CIA-Veh rats. While antiTNFα and anti-IL-1 partially normalized serum RANKL without any changes in serum TRACP 5B, OPG-Fc treatment reduced serum TRACP 5B by over 90% in both CIA and AIA rats. CIA-Veh and AIA-Veh rats had increased serum α1AGP, IL-1β, IL-8 and chemokine (C-C motif) ligand 2 (CCL2), and AIA-Veh rats also had significantly greater serum PGE2, TNFα and IL-17. Anti-TNFα reduced systemic α1AGP, CCL2 and PGE2 in AIA rats, while anti-IL-1 decreased systemic α1AGP, IL-8 and PGE2. In contrast, RANKL inhibition by OPG-Fc did not lessen systemic cytokine levels in either model.Conclusions
Anti-TNFα or anti-IL-1 therapy inhibited parameters of local and systemic inflammation, and partially reduced local but not systemic bone loss in AIA and CIA rats. RANKL inhibition prevented local and systemic bone loss without significantly inhibiting local or systemic inflammatory parameters. 相似文献29.
30.
Laura R Jarboe Ammara Khalid Efrain Rodriguez Ocasio Kimia Fashkami Noroozi 《Journal of industrial microbiology & biotechnology》2022,49(2)
The goal of cost-effective production of fuels and chemicals from biomass has been a substantial driver of the development of the field of metabolic engineering. The resulting design principles and procedures provide a guide for the development of cost-effective methods for degradation, and possibly even valorization, of plastic wastes. Here, we highlight these parallels, using the creative work of Lonnie O''Neal (Neal) Ingram in enabling production of fuels and chemicals from lignocellulosic biomass, with a focus on ethanol production as an exemplar process. 相似文献