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691.
Nauman Siddiqi MD Morton J. Kern MD FACC Pranav M. Patel MD FACC 《Catheterization and cardiovascular interventions》2012,79(5):809-811
A 34‐year‐old woman presented with refractory ascites and edema. Echocardiography revealed normal left ventricular function with a restrictive diastolic filling pattern. Tissue Doppler velocities of the mitral annulus were normal. Cardiac magnetic resonance imaging (MRI) revealed a focal region of pericardial thickening anterior to the right ventricle and normal thickness pericardium in the other segments. However, abnormal delayed enhancement MRI (consistent with inflammation) was present in both the thickened and the normal pericardial segments. Invasive hemodynamics confirmed constrictive physiology and the patient underwent successful pericardiectomy. This case highlights the utility of multimodality imaging in the diagnosis of constrictive pericarditis and the underappreciated fact that the pericardium need not be globally thickened to cause hemodynamically significant constrictive physiology.© 2012 Wiley Periodicals, Inc. 相似文献
692.
693.
The use of alkali therapy in severe diabetic ketoacidosis 总被引:1,自引:0,他引:1
694.
Javaid Nauman Bjarne M. Nes Carl J. Lavie Andrew S. Jackson Xuemei Sui Jeff S. Coombes Steven N. Blair Ulrik Wisløff 《Mayo Clinic proceedings. Mayo Clinic》2017,92(2):218-227
Objective
To assess the predictive value of estimated cardiorespiratory fitness (eCRF) and evaluate the additional contribution of traditional risk factors in cardiovascular disease (CVD) mortality prediction.Participants and Methods
The study included healthy men (n=18,721) and women (n=19,759) aged 30 to 74 years. A nonexercise algorithm estimated cardiorespiratory fitness. Cox proportional hazards models evaluated the primary (CVD mortality) and secondary (all-cause, ischemic heart disease, and stroke mortality) end points. The added predictive value of traditional CVD risk factors was evaluated using the Harrell C statistic and net reclassification improvement.Results
After a median follow-up of 16.3 years (range, 0.04-17.4 years), there were 3863 deaths, including 1133 deaths from CVD (734 men and 399 women). Low eCRF was a strong predictor of CVD and all-cause mortality after adjusting for established risk factors. The C statistics for eCRF and CVD mortality were 0.848 (95% CI, 0.836-0.861) and 0.878 (95% CI, 0.862-0.894) for men and women, respectively, increasing to 0.851 (95% CI, 0.839-0.863) and 0.881 (95% CI, 0.865-0.897), respectively, when adding clinical variables. By adding clinical variables to eCRF, the net reclassification improvement of CVD mortality was 0.014 (95% CI, ?0.023 to 0.051) and 0.052 (95% CI, ?0.023 to 0.127) in men and women, respectively.Conclusion
Low eCRF is independently associated with CVD and all-cause mortality. The inclusion of traditional clinical CVD risk factors added little to risk discrimination and did not improve the classification of risk beyond this simple eCRF measurement, which may be proposed as a practical and cost-effective first-line approach in primary prevention settings. 相似文献695.
Qureshi HS Salama ME Chitale D Bansal I Ma CK Raju U Ormsby A Lee MW 《The American Journal of dermatopathology》2004,26(5):353-358
BACKGROUND: Primary cutaneous mucinous carcinoma (PCMC) is a rare malignancy with probable apocrine differentiation. It is important to differentiate it from metastatic mucinous carcinoma (MMC), especially from the breast. The histologic and immunohistochemical features overlap between PCMC and breast mucinous carcinomas. In this study, we introduce the presence of myoepithelial component in PCMC as a new morphologic parameter to distinguish it from MMC from either breast or sites elsewhere in the body. MATERIALS AND METHODS: We studied 7 cases of PCMC. The possible in situ component in the tumor was assessed by the presence of a peripheral myoepithelial cell layer. Myoepithelial cell differentiation was confirmed with immunohistochemical stains for p63, CK 5/6, calponin, smooth muscle actin (SMA), HHF-35, and CD10. Estrogen and progesterone receptor (ER/PR), gross cystic disease fluid protein (GCDFP 15), CK7, CK20, and S-100 immunostains were also performed. RESULTS: Histologically, multiple small monomorphic epithelial islands floating in multilocular pools of mucin characterized the tumor. Focally, epithelial islands were bordered by dermal connective tissue at the periphery of mucin pools. Secretory snouts were apparent in all cases providing evidence for apocrine differentiation. In 5 of the 7 cases, an in situ component was identified as epithelial islands being bounded by a myoepithelial layer, which was highlighted by p63, CK 5/6, calponin, SMA, and HHF-35. ER/PR and CK7 were positive in all the cases. GCDFP-15 and CD10 were focally positive in the tumor cells and myoepithelial cells, respectively. All 7 cases were negative for S-100 and CK 20. CONCLUSION: We conclude that an in situ component is frequently present in PCMC (5/7) and may help in distinguishing this entity from MMC, especially of breast origin. Furthermore, it may provide insight into the pathogenetic mechanism of mucinous carcinoma evolving from in situ carcinoma with luminal mucinous distention to cellular tumor with a little surrounding mucin. 相似文献
696.
Trine Moholdt Carl J. Lavie Javaid Nauman 《Journal of the American College of Cardiology》2018,71(10):1094-1101
Background
Individuals with coronary heart disease (CHD) are recommended to be physically active and to maintain a healthy weight. There is a lack of data on how long-term changes in body mass index (BMI) and physical activity (PA) relate to mortality in this population.Objectives
This study sought to determine the associations among changes in BMI, PA, and mortality in individuals with CHD.Methods
The authors studied 3,307 individuals (1,038 women) with CHD from the HUNT (Nord-Trøndelag Health Study) with examinations in 1985, 1996, and 2007, followed until the end of 2014. They calculated the hazard ratio (HR) for all-cause and cardiovascular disease (CVD) mortality according to changes in BMI and PA, and estimated using Cox proportional hazards regression models adjusted for age, smoking, blood pressure, diabetes, alcohol, and self-reported health.Results
There were 1,493 deaths during 30 years of follow-up (55% from CVD, median 15.7 years). Weight loss, classified as change in BMI <–0.10 kg/m2/year, associated with increased all-cause mortality (adjusted HR: 1.30; 95% confidence interval [CI]: 1.12 to 1.50). Weight gain, classified as change in BMI ≥0.10 kg/m2/year, was not associated with increased mortality (adjusted HR: 0.97; 95% CI: 0.87 to 1.09). Weight loss only associated with increased risk in those who were normal weight at baseline (adjusted HR: 1.38; 95% CI: 1.11 to 1.72). There was a lower risk for all-cause mortality in participants who maintained low PA (adjusted HR: 0.81; 95% CI: 0.67 to 0.97) or high PA (adjusted HR: 0.64; 95% CI: 0.50 to 0.83), compared with participants who were inactive over time. CVD mortality associations were similar as for all-cause mortality.Conclusions
The study observed no mortality risk reductions associated with weight loss in individuals with CHD, and reduced mortality risk associated with weight gain in individuals who were normal weight at baseline. Sustained PA, however, was associated with substantial risk reduction. 相似文献697.
Aqil F Gupta A Munagala R Jeyabalan J Kausar H Sharma RJ Singh IP Gupta RC 《Nutrition and cancer》2012,64(3):428-438
Colored fruits, particularly berries, are highly chemoprotective because of their antioxidant, antiproliferative, and antiinflammatory activities. We report the cancer chemoprotective potential of Syzygium cumini L., commonly known as jamun or Indian blackberry. Anthocyanins and other polyphenolics were extracted with acidic ethanol and enriched by amberlite XAD7/HP20 (1:1). The pulp powder was found to contain 0.54% anthocyanins, 0.17% ellagic acid/ellagitannins, and 1.15% total polyphenolics. Jamun seed contained no detectable anthocyanins but had higher amounts of ellagic acid/ellagitannins (0.5%) and total polyphenolics (2.7%) than the pulp powder. Upon acid hydrolysis, the pulp extract yielded 5 anthocyanidins by HPLC: malvidin (44.4%), petunidin (24.2%), delphinidin (20.3%), cyanidin (6.6%), and peonidin (2.2%). Extracts of both jamun pulp (1,445 ± 64 μmol of trolox equivalent (TE)/g) and seeds (3,379 ± 151 μM of TE/g) showed high oxygen radical absorbance capacity. Their high antioxidant potential was also reflected by 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)- and 2,2-diphenyl-1-picrylhydrazyl-scavenging and ferrous ion-chelating activities. We also analyzed antiproliferative activity of jamun extracts against human lung cancer A549 cells. The hydrolyzed pulp and seed extracts showed significant antiproliferative activity. However, unhydrolyzed extracts showed much less activity. These data showed that in addition to 5 anthocyanidins, jamun contains appreciable amounts of ellagic acid/ellagitannins, with high antioxidant and antiproliferative activities. 相似文献
698.
Hina J Panchal Joel B Durinka Jeromy Patterson Farah Karipineni Sarah Ashburn Eric Siskind Jorge Ortiz 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2015,17(12):1074-1084
BackgroundThe Model for End‐stage Liver Disease (MELD) has been used as a prognostic tool since 2002 to predict pre‐transplant mortality. Increasing proportions of transplant candidates with higher MELD scores, combined with improvements in transplant outcomes, mandate the need to study surgical outcomes in patients with MELD scores of ≥40.MethodsA retrospective longitudinal analysis of United Network for Organ Sharing (UNOS) data on all liver transplantations performed between February 2002 and June 2011 (n= 33 398) stratified by MELD score (<30, 30–39, ≥40) was conducted. The primary outcomes of interest were short‐ and longterm graft and patient survival. A Kaplan–Meier product limit method and Cox regression were used. A subanalysis using a futile population was performed to determine futility predictors.ResultsOf the 33 398 transplant recipients analysed, 74% scored <30, 18% scored 30–39, and 8% scored ≥40 at transplantation. Recipients with MELD scores of ≥40 were more likely to be younger (P < 0.001), non‐White and to have shorter waitlist times (P< 0.001). Overall patient survival correlated inversely with increasing MELD score; this trend was consistent for both short‐term (30 days and 90 days) and longterm (1, 3 and 5 years) graft and patient survival. In multivariate analysis, increasing age, African‐American ethnicity, donor obesity and diabetes were negative predictors of survival. Futility predictors included patient age of >60 years, obesity, peri‐transplantation intensive care unit hospitalization with ventilation, and multiple comorbidities.ConclusionsLiver transplantation in recipients with MELD scores of ≥40 offers acceptable longterm survival outcomes. Futility predictors indicate the need for prospective follow‐up studies to define the population to gain the highest benefit from this precious resource. 相似文献
699.
Effect of porosity on the fluid flow characteristics and mechanical properties of tantalum scaffolds 总被引:1,自引:0,他引:1
Shimko DA Shimko VF Sander EA Dickson KF Nauman EA 《Journal of biomedical materials research. Part B, Applied biomaterials》2005,73(2):315-324
In many cases of traumatic bone injury, bone grafting is required. The primary source of graft material is either autograft or allograft. The use of both material sources are well established, however, both suffer limitations. In response, many grafting alternatives are being explored. This article specifically focuses on a porous tantalum metal grafting material (Trabecular Metaltrade mark) marketed by Zimmer. Twenty-one cylindrical scaffolds were manufactured (66% to 88% porous) and tested for porosity, intrinsic permeability, tangent elastic modulus, and for yield stress and strain behavior. Scaffold microstructural geometries were also measured. Tantalum scaffold intrinsic permeability ranged from 2.1 x 10(-10) to 4.8 x 10(-10) m(2) and tangent elastic modulus ranged from 373 MPa to 2.2 GPa. Both intrinsic permeability and tangent elastic modulus closely matched porosity-matched cancellous bone specimens from a variety of species and anatomic locations. Scaffold yield stress ranged from 4 to 12.7 MPa and was comparable to bovine and human cancellous bone. Yield strain was unaffected by scaffold porosity (average = 0.010 mm/mm). Understanding these structure-function relationships will help complete the basic physical characterization of this new material and will aid in the development of realistic mathematical models, ultimately enhancing future implant designs utilizing this material. 相似文献
700.
Alok K. Pandey K. Sony Reddy Tajali Sahar Sonal Gupta Hina Singh E. Jyotheeswara Reddy Mohd Asad Faiza A. Siddiqui Pankaj Gupta Bijender Singh Kunal R. More Asif Mohmmed Chetan E. Chitnis Virander S. Chauhan Deepak Gaur 《Infection and immunity》2013,81(2):441-451
Blood-stage malaria vaccines that target single Plasmodium falciparum antigens involved in erythrocyte invasion have not induced optimal protection in field trials. Blood-stage malaria vaccine development has faced two major hurdles, antigenic polymorphisms and molecular redundancy, which have led to an inability to demonstrate potent, strain-transcending, invasion-inhibitory antibodies. Vaccines that target multiple invasion-related parasite proteins may inhibit erythrocyte invasion more efficiently. Our approach is to develop a receptor-blocking blood-stage vaccine against P. falciparum that targets the erythrocyte binding domains of multiple parasite adhesins, blocking their interaction with their receptors and thus inhibiting erythrocyte invasion. However, with numerous invasion ligands, the challenge is to identify combinations that elicit potent strain-transcending invasion inhibition. We evaluated the invasion-inhibitory activities of 20 different triple combinations of antibodies mixed in vitro against a diverse set of six key merozoite ligands, including the novel ligands P. falciparum apical asparagine-rich protein (PfAARP), EBA-175 (PfF2), P. falciparum reticulocyte binding-like homologous protein 1 (PfRH1), PfRH2, PfRH4, and Plasmodium thrombospondin apical merozoite protein (PTRAMP), which are localized in different apical organelles and are translocated to the merozoite surface at different time points during invasion. They bind erythrocytes with different specificities and are thus involved in distinct invasion pathways. The antibody combination of EBA-175 (PfF2), PfRH2, and PfAARP produced the most efficacious strain-transcending inhibition of erythrocyte invasion against diverse P. falciparum clones. This potent antigen combination was selected for coimmunization as a mixture that induced balanced antibody responses against each antigen and inhibited erythrocyte invasion efficiently. We have thus demonstrated a novel two-step screening approach to identify a potent antigen combination that elicits strong strain-transcending invasion inhibition, supporting its development as a receptor-blocking malaria vaccine. 相似文献