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991.
Wald DN Vermaat HM Zang S Lavik A Kang Z Peleg G Gerson SL Bunting KD Agarwal ML Roth BL Tse W 《Cancer research》2008,68(11):4369-4376
As the pathophysiology of acute myelogenous leukemia (AML) involves a block of myeloid maturation, a desirable therapeutic strategy is to induce leukemic cell maturation to increase the efficacy and to avoid the side effects of traditional chemotherapeutics. Through a compound library screen, 6-benzylthioinosine (6BT) was identified as a promising differentiation-inducing agent. 6BT induces monocytic differentiation of myeloid leukemia cell lines such as HL-60 and OCI-AML3, as well as primary patient samples as evidenced by morphology, immunophenotyping, and nitroblue tetrazolium reduction. Not only can 6BT induce differentiation but a subset of AML cell lines such as MV4-11 and HNT34 instead undergo 6BT-mediated cell death. Despite inducing cell death in some leukemic cells, 6BT exhibits extremely low toxicity on several nonmalignant cells such as fibroblasts, normal bone marrow, and endothelial cells. This toxicity profile may relate to the function of 6BT as an inhibitor of the nucleoside transporter, ent1, which is thought to prevent it from entering many cell types. In contrast, 6BT likely enters at least some leukemic cell lines as shown by its requirement for phosphorylation for its differentiation activity. 6BT is also able to synergize with currently used myeloid differentiation agents such as ATRA and decitabine. Early studies indicate that the mechanism of action of this compound may involve ATP depletion that leads to growth inhibition and subsequent differentiation. Besides in vitro activity, 6BT also shows the ability to impair HL-60 and MV4-11 tumor growth in nude mice. 6BT is a promising new monocytic differentiation agent with apparent leukemic cell-specific activity. 相似文献
992.
Z Tang R Du S Jiang C Wu D S Barkauskas J Richey J Molter M Lam C Flask S Gerson A Dowlati L Liu Z Lee B Halmos Y Wang J A Kern P C Ma 《British journal of cancer》2008,99(6):911-922
Despite clinical approval of erlotinib, most advanced lung cancer patients are primary non-responders. Initial responders invariably develop secondary resistance, which can be accounted for by T790M-EGFR mutation in half of the relapses. We show that MET is highly expressed in lung cancer, often concomitantly with epidermal growth factor receptor (EGFR), including H1975 cell line. The erlotinib-resistant lung cancer cell line H1975, which expresses L858R/T790M-EGFR in-cis, was used to test for the effect of MET inhibition using the small molecule inhibitor SU11274. H1975 cells express wild-type MET, without genomic amplification (CNV=1.1). At 2 μM, SU11274 had significant in vitro pro-apoptotic effect in H1975 cells, 3.9-fold (P=0.0015) higher than erlotinib, but had no effect on the MET and EGFR-negative H520 cells. In vivo, SU11274 also induced significant tumour cytoreduction in H1975 murine xenografts in our bioluminescence molecular imaging assay. Using small-animal microPET/MRI, SU11274 treatment was found to induce an early tumour metabolic response in H1975 tumour xenografts. MET and EGFR pathways were found to exhibit collaborative signalling with receptor cross-activation, which had different patterns between wild type (A549) and L858R/T790M-EGFR (H1975). SU11274 plus erlotinib/CL-387,785 potentiated MET inhibition of downstream cell proliferative survival signalling. Knockdown studies in H1975 cells using siRNA against MET alone, EGFR alone, or both, confirmed the enhanced downstream inhibition with dual MET–EGFR signal path inhibition. Finally, in our time-lapse video-microscopy and in vivo multimodal molecular imaging studies, dual SU11274-erlotinib concurrent treatment effectively inhibited H1975 cells with enhanced abrogation of cytoskeletal functions and complete regression of the xenograft growth. Together, our results suggest that MET-based targeted inhibition using small-molecule MET inhibitor can be a potential treatment strategy for T790M-EGFR-mediated erlotinib-resistant non-small-cell lung cancer. Furthermore, optimised inhibition may be further achieved with MET inhibition in combination with erlotinib or an irreversible EGFR-TKI. 相似文献
993.
994.
Gerson Aparecido Foratori-Junior Leonardo Silva Mscoli Carolina Cordeiro Marchese Eliel Soares Orenha Silvia Helena de Carvalho Sales-Peres 《International dental journal》2021,71(3):242-249
ObjectiveThis study aimed to compare the systemic and periodontal conditions between morbidly obese patients with and without hypertension who were candidates for bariatric surgery.MethodsThe study cohort had 111 morbidly obese patients stratified into two groups: patients with (G1 = 54) and without (G2 = 57) arterial hypertension. The following characteristics were compared between the two groups: (i) education level; (ii) anthropometric parameters [weight, height, body mass index (BMI), waist and hip circumferences and waist-to-hip ratio (WHR)]; (iii) risk of developing cardiovascular diseases (based on patients’ sex, age and WHR); (iv) behaviours regarding oral hygiene; and (v) periodontal status. The t-test, Mann–Whitney U-test, chi-square test and logistic regression were applied, with a significance level of 5%.ResultsPatients in G1 had a lower level of education (P = 0.002). There were no intergroup differences for weight (P = 0.211), height (P = 0.126), BMI (P = 0.551), waist circumference (P = 0.859) and WHR (P = 0.067); however, patients in G2 had a smaller hip circumference (P = 0.029), and 78% of patients in G1 had a high/very high risk of developing cardiovascular diseases. The prevalence of periodontitis was 72.2% (n = 39) in G1 and 38.6% (n = 22) in G2. On logistic regression analysis, age [adjusted odds ratio (OR) = 1.07; 95% CI = 1.01–1.13; P = 0.008) and the presence of arterial hypertension (OR = 2.77; 95% CI = 1.17–6.56; P = 0.019) were identified as the independent variables associated with periodontitis.ConclusionMorbid obesity and arterial hypertension are associated with a higher prevalence of cardiovascular diseases. Moreover, morbidly obese patients with hypertension have a higher prevalence of periodontitis and greater severity of periodontal disease than those without hypertension. 相似文献
995.
996.
Eduardo K. Moioli Paul A. Clark Mo Chen James E. Dennis Helaman P. Erickson Stanton L. Gerson Jeremy J. Mao 《PLoS Clinical Trials》2008,3(12)
Poor angiogenesis is a major road block for tissue repair. The regeneration of virtually all tissues is limited by angiogenesis, given the diffusion of nutrients, oxygen, and waste products is limited to a few hundred micrometers. We postulated that co-transplantation of hematopoietic and mesenchymal stem/progenitor cells improves angiogenesis of tissue repair and hence the outcome of regeneration. In this study, we tested this hypothesis by using bone as a model whose regeneration is impaired unless it is vascularized. Hematopoietic stem/progenitor cells (HSCs) and mesenchymal stem/progenitor cells (MSCs) were isolated from each of three healthy human bone marrow samples and reconstituted in a porous scaffold. MSCs were seeded in micropores of 3D calcium phosphate (CP) scaffolds, followed by infusion of gel-suspended CD34+ hematopoietic cells. Co-transplantation of CD34+ HSCs and CD34− MSCs in microporous CP scaffolds subcutaneously in the dorsum of immunocompromized mice yielded vascularized tissue. The average vascular number of co-transplanted CD34+ and MSC scaffolds was substantially greater than MSC transplantation alone. Human osteocalcin was expressed in the micropores of CP scaffolds and was significantly increased upon co-transplantation of MSCs and CD34+ cells. Human nuclear staining revealed the engraftment of transplanted human cells in vascular endothelium upon co-transplantation of MSCs and CD34+ cells. Based on additional in vitro results of endothelial differentiation of CD34+ cells by vascular endothelial growth factor (VEGF), we adsorbed VEGF with co-transplanted CD34+ and MSCs in the microporous CP scaffolds in vivo, and discovered that vascular number and diameter further increased, likely owing to the promotion of endothelial differentiation of CD34+ cells by VEGF. Together, co-transplantation of hematopoietic and mesenchymal stem/progenitor cells may improve the regeneration of vascular dependent tissues such as bone, adipose, muscle and dermal grafts, and may have implications in the regeneration of internal organs. 相似文献
997.
998.
de Meneses Francisco Gerson A. Teles Ariel Soares Nunes Monara da Silva Farias Daniel Teixeira Silmar 《Brain topography》2022,35(4):464-480
Brain Topography - Software such as EEGLab has enabled the treatment and visualization of the tracing and cortical topography of the electroencephalography (EEG) signals. In particular, the... 相似文献
999.
érique José Peixoto De Miranda Gerson Sobrinho Salvador De Oliveira Felício Lopes Roque Sílvia Regina Dos Santos Rodrigo Diaz Olmos Paulo Andrade Lotufo 《Revista do Instituto de Medicina Tropical de S?o Paulo》2014,56(4):313-324
Introduction: Urinary tract infection (UTI) has a high incidence and
recurrence, therefore, treatment is empirical in the majority of cases.
Objectives: The aim of this study was to analyze the urine cultures
performed at a secondary hospital, during two periods, 2005-2006 and 2010-2011, and
to estimate the microbial resistance.
Patients and methods: We analyzed 11,943 aerobic urine cultures
according to basic demographic data and susceptibility to antibiotics in accordance
with the Clinical and Laboratory Standards Institute (CLSI) for Vitek 1 and 2.
Results: Most of our cohort consisted of young adult females that were
seen at the Emergency Department. E. coli was the most frequent
(70.2%) among the 75 species isolated. Resistance of all isolates was ≥ 20% for
trimethoprim/sulfamethoxazole (TMP/SMX), norfloxacin, nitrofurantoin, cefazolin and
nalidixic acid. Although E. coli was more susceptible (resistance ≥
20% for TMP/SMX and nalidixic acid) among all of the isolates, when classified by the
number and percentage of antibiotic resistance. Global resistance to fluoroquinolones
was approximately 12%. Risk factors for E. coli were female gender
and an age less than 65 years. Men and patients older than 65 years of age, presented
more resistant isolates. Extended spectrum beta-lactamases (ESBL) were identified in
173 out of 5,722 Gram-negative isolates (3.0%) between 2010 and 2011.
Conclusion:
E. coli was the most frequent microbe isolated in the urine cultures
analyzed in this study. There was a significant evolution of bacterial resistance
between the two periods studied. In particular, the rise of bacterial resistance to
fluoroquinolones was concerning. 相似文献
1000.
Audrey Borghi-Silva Renata Gonçalves Mendes Renata Trimer Gerson Cipriano Jr. 《Progress in cardiovascular diseases》2014
Cardiovascular diseases (CVD) are among the leading causes of morbidity and mortality in Brazil. Cardiac rehabilitation (CR) is a program composed of structured exercise training, comprehensive education and counseling to positively impact functional, psychological, social, and quality of life aspects in these patients. However, the delivery of formal CR programs is limited to major metropolitan centers in Brazil and does not exist in much of the national territory, specifically in the North and Northeast regions. Barriers to the inclusion of qualified patients are lack of referral by the health professionals, as well as transportation difficulties, low income, lack of insurance coverage, and low educational level. Government efforts to implement CR programs on a broader scale, to reach a larger portion of the CVD population, are imperative. Additional research must be focused on the assessment of CR referral and adherence patterns as well as the effectiveness of different CR delivery models. 相似文献