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1.
BACKGROUND: Myocardial perfusion imaging (MPI) is a well-established diagnostic method for evaluation and risk stratification of coronary artery disease (CAD).We undertook this study to validate both the positive predictive value (when compared to cardiac catheterization) and the prognosis afforded by MPI in a group of minority women patients. MATERIAL/METHODS: The database of our Nuclear Imaging and Catheterization Laboratory was retrospectively queried for consecutive minority (African-American, Hispanic and Asian) women patients who underwent MPI and cardiac catheterization within 90 days of each other. Patients with recent revascularization were excluded. Attenuation/scatter correction was utilized in the final interpretation of the study. RESULTS: Of the 54 women patients who underwent MPI, 7 underwent exercise stress testing, 26 had stress testing with adenosine, 18 with dipyridamole and 3 with dobutamine. Eighteen patients (53%) had same number of vessels predicted by MPI and coronary angiography (7 patients with triple vessel disease, 7 with 2-vessel disease and 4 with single vessel disease). Five (3 with intermediate and 2 with high risk scans) out of the 54 patients (9.3%) were dead at 2 years. The sensitivity, specificity and positive predictive value of MPI as compared to angiography were 87.2%, 26.7%, 75.6% and 44.4% respectively. CONCLUSIONS: The sensitivity of MPI in this group of patients is comparable to the general population though the specificity is lower in spite of using attenuation and scatter correction. Low risk perfusion scan signifies favorable prognosis at 2 years with regards to mortality.  相似文献   
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Antitumor and antimetastatic activity of the angiogenesis inhibitor O-(chloroacetyl-carbamoyl) fumagillol (TNP-470), a semisynthetic analogue offumagillin, was evaluated in breast cancer cell lines. In an in vitro MTTassay, after 72 hrs continuous exposure to TNP-470, growth inhibition wasobserved in all seven cell lines of murine (JYG-A, JYG-B, DD-762, andBALB/c-MC) or human (KPL-1, MDA-MB-231, and MKL-F) origin, in which the50% inhibitory concentrations (IC50) at 72 hrstreatment were 4.6, 4.4, 4.6, 10.1, 35.0, 25.3, and 33.4 µg/ml,respectively. In an in vivo assay using JYG-A, JYG-B, KPL-1, and MDA-MB-231cells by orthotopic (right thoracic mammary fat pad) transplantation infemale nude mice, TNP-470 at 30 or 50 mg/kg body weight was injected s.c.every other day from the day of tumor cell inoculation until the end of theexperiment. The inhibitory effect on primary tumor growth was obtained inall four cell lines in a dose-dependent manner. In the 50 mg/kgTNP-470-treated group, the reductions in tumor weight of the JYG-A, JYG-B,KPL-1, and MDA-MB-231 cells with respect to the controls were 50%,30%, 4%, and 49%, respectively. Metastasis was seen inthe JYG-A, JYG-B, and KPL-1 cells. The numbers of mice bearing pulmonarymetastases of JYG-A and JYG-B cells and regional axillary lymph nodemetastases of KPL-1 cells were reduced, and TNP-470 at the 50 mg/kg dose toKPL-1 cells significantly reduced lymph node metastases compared with thecontrol. Although the weight gain was retarded in the TNP-470-treated mice,weight loss was not seen. TNP-470 was highly effective in the treatment ofbreast cancer cells. These results suggest that the clinical use of TNP-470may be a promising treatment for breast cancer patients.  相似文献   
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Abstract

Gelatin, chitosan and nano calcium phosphate based composite scaffold with tailored architectures and properties has great potential for bone regeneration. Herein, we aimed to improve the physico chemical, mechanical and osteogenic properties of 3D porous scaffold by incorporation of dihydrogen calcium phosphate anhydrous (DCPA) nanoparticles into biopolymer matrix with variation in composition in the prepared scaffolds. Scaffolds were prepared from the slurry containing gelatin, chitosan and synthesized nano DCPA particle using lyophilization technique. DCPA nano particles were synthesized using calcium carbonate and phosphoric acid in water–ethanol medium. XRD pattern showed phase pure DCPA in synthesized nanopowder. Scaffolds were prepared by addition of DCPA nanoparticles to the extent of 5–10?wt% of total polymer into gelatin–chitosan solution with solid loading varying between 2.5 and 2.75?wt%. The prepared scaffold showed interconnected porosity with pore size varying between 110 and 200 micrometer. With addition of DCPA nanoparticles, average pore size of the prepared scaffolds decreased. With increase in nano ceramic phase content from 5?wt% to 10?wt% of total polymer, the compressive strength of the scaffold increased. Scaffold containing 10?wt% DCPA showed the highest average compressive strength of 2.2?MPa. Higher cellular activities were observed in DCPA containing scaffolds as compared to pure gelatin chitosan scaffold suggesting the fact that nano DCPA addition into the scaffold promoted better osteoblast adhesion and proliferation as evident from MTT assay and scanning electron microscopic (SEM) investigation of osteoblast cultured scaffolds. A higher degree of lamellopodia and filopodia extensions and better spreading behavior of osteoblasts were observed in FESEM micrographs of MG 63 cultured DCPA containing scaffold. The results demonstrated that both mechanical strength and osteogenic properties of gelatin–chitosan scaffold could be improved by addition of anhydrous dihydrogen calcium phosphate nanoparticles into it.  相似文献   
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Journal of Thrombosis and Thrombolysis - Studies of patients with COVID-19 have demonstrated markedly dysregulated coagulation and a high risk of morbid arterial and venous thrombotic events....  相似文献   
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Titanium alloys are the most commonly used dental and orthopedic implant materials due to their proven biocompatibility and mechanical properties. The native oxide layer (TiO2 layer) formed on such Ti-based implants acts as the self-protecting layer against possible ion release. Increasing the oxide layer thickness further on such TiO2 implants even opens the triggering of the osseointegration process if the oxide layer is having a certain degree of roughness, preferably higher. This work reports a novel photocatalytic patterning of sputter deposited TiO2 layers with flower-like Au structures to enhance the early osteoblastic activity. The prepared hierarchical Au structures, composed of micro- and nanoscale features on the top, lead to improved number of filopodia formation. This suggest that proposed Au–TiO2 surface may foster the cell attachment and as well as cell proliferation.

Flower-like hierarchical Au structures, composed of micro- and nanoscale features, lead to higher number of filopodia formation on TiO2 thin films.  相似文献   
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BackgroundThe association of depression and epilepsy is thought to be bidirectional. The present study aimed to evaluate the prevalence of depression in patients on antiepileptic drugs (AEDs) and factors affecting it.MethodsIn this preliminary cross sectional study, patients at epilepsy clinic of a tertiary care centre were studied for occurrence of depression, using Hospital Anxiety and Depression Scale (HADS-D) and Patient Health Questionnaire (PHQ-2) scales. Correlation analysis was carried out to determine the factors associated with presence of depression in these patients.ResultsA total of 12 AEDs (maximum 5 per patient including older and newer) were prescribed to 933 patients in different treatment regimens over a period of 3 years. The median age of the patients was 22 years (10–77) and among them 63.5% were men. Mild and clinically relevant depression occurred in 279 (29.9%) and 223 (23.9%) patients, respectively. Mean HADS-D and PHQ-2 score was significantly higher with polytherapy as compared to monotherapy (p < 0.001). Patients on levetiracetam exhibited significantly higher HADS-D score in comparison to phenytoin (p < 0.001), carbamazepine (p < 0.001) and sodium valproate (p < 0.05). However, there was no significant difference in PHQ score among patients on monotherapy of different AEDs. Multivariate regression analysis suggested correlation between depression and seizure frequency, total number of AEDs and their load (p < 0.001).ConclusionDepressive symptoms were found to be present in more than half of the patients with epilepsy which require detailed work up for depression. Levetiracetam was found to be associated with a higher incidence of subclinical depression which needs further investigation.  相似文献   
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Background  

Increased intestinal permeability (IP) has been implicated in the etiopathogenesis, disease activity and relapse of Crohn’s disease (CD). Glutamine, the major fuel for the enterocytes, may improve IP.  相似文献   
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Background and Aim:  Patients with chronic pancreatitis are often malnourished. The role of malnutrition in the pathogenesis of chronic pancreatitis is unclear. The aim of the present article was to study prospectively the cause and effect relationship of malnutrition with idiopathic chronic pancreatitis in a case–control study.
Methods:  Consecutive patients with chronic pancreatitis underwent anthropometry, nutritional and dietary assessments. For dietary assessment, food frequency questionnaire and 24-hour dietary recall methods were used. Primary outcome measure was cause and effect relationship of malnutrition with idiopathic chronic pancreatitis.
Results:  Of 201 patients with chronic pancreatitis, 120 had idiopathic chronic pancreatitis (mean age 29.60 years, 74 males) who formed the study group. None of the patients consumed cassava. The nutritional status and dietary intake of the patients before the onset of chronic pancreatitis were comparable with those of controls with 20.6% of patients and 22.5% of controls being malnourished (body mass index [BMI] < 18.5). After the onset of chronic pancreatitis, 56.5% of patients lost weight and significantly more patients became malnourished compared with controls (45.8% vs 22.5%; P  < 0.001). The causes of weight loss were diabetes, higher calories from proteins, and pseudocyst.
Conclusion:  Malnutrition was not a cause of idiopathic chronic pancreatitis and weight loss occurred as an effect of chronic pancreatitis. Cassava was not found to be a cause of idiopathic chronic pancreatitis.  相似文献   
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