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21.
Guido Cimoli Monica Valenti Elvira Noviello Silvio Parodi Alessandra Mazzoni Elisabetta Rovini Fabio De Sessa Patrizia Russo 《Journal of cancer research and clinical oncology》1995,121(3):155-163
Human ovarian cancer cells A2780, selected for resistance to doxorubicin (A2780-DX3), are crossresistant to various other topoisomerase-II-targeted drugs but not to vinblastine. The parental cell line was very sensitive to doxorubicin-, mitoxantrone- or etoposide (VP16)-induced DNA single-strand breaks, under deproteinizing conditions. In contrast, little or no DNA strand breakage was seen in resistant A2780-DX3 cells, even at very high concentrations, indicating a good correlation, with cytotoxicity. No significant alterations in cellular drug uptake were observed in DX3 cells. Further studies showed that the nuclei isolated from resistant cells were also resistant to mitoxantroneor VP16-induced single-strand breaks, indicating that nuclear modifications in resistant cells are responsible for this resistance. Catalytic activity in crude nuclear extracts from wild-type and DX3 cells was almost equal. However, an assay that specifically measures generation of 5-protein-linked breaks in32P-labeled 3 DNA revealed that, DNA cleavage activity in nuclear extract from the DX3 cell line is profoundly resistant to a stimulation by VP16. These data indicate that stimulation of topoisomerase-II-mediated DNA cleavage is responsible for topoisomerase-II-targeted drugcytotoxicity rather than loss of normal topoisomerase catalytic function. These data support the hypothesis that A2780-DX3 cells display an atypical multidrug resistance.Abbreviations
MDR
multidrug resistance
-
SSB
Single-strand break 相似文献
22.
Fred Stephen Sarfo Albert Akpalu Ansumana Bockarie Lambert Appiah Samuel Blay Nguah Nana Kwame Ayisi-Boateng Sheila Adamu Christiana Neizer Agnes Arthur Richard Nyamekye Kwabena Agyenim-Boateng Raelle Tagge Nathaniel Adusei-Mensah Michael Ampofo Ruth Laryea Arti Singh John Humphry Amuasi Bruce Ovbiagele 《Journal of stroke and cerebrovascular diseases》2021,30(8):105888
ObjectivesThe Sub-Saharan African (SSA) region now has the highest estimated effect size of hypertension for stroke causation worldwide. An urgent priority for countries in SSA is to develop and test self-management interventions to control hypertension among those at highest risk of adverse outcomes. Thus the overall objective of the Phone-based Intervention under Nurse Guidance after Stroke II study (PINGS-2) is to deploy a hybrid study design to assess the efficacy of a theoretical-model-based, mHealth technology-centered, nurse-led, multi-level integrated approach to improve longer term blood pressure (BP) control among stroke survivors.Materials and methodsA phase III randomized controlled trial involving 500 recent stroke survivors to be enrolled across 10 Ghanaian hospitals. Using a computer-generated sequence, patients will be randomly assigned 1:1 into the intervention or usual care arms. The intervention comprises of (i) home BP monitoring at least once weekly with nurse navigation for high domiciliary BP readings; (2) medication reminders using mobile phone alerts and (3) education on hypertension and stroke delivered once weekly via audio messages in preferred local dialects. The intervention will last for 12 months. The control group will receive usual care as determined by local guidelines. The primary outcome is the proportion of patients with systolic BP <140 mm Hg at 12 months. Secondary outcomes will include medication adherence, self-management of hypertension, major adverse cardiovascular events, health related quality of life and implementation outcomes.ConclusionAn effective PINGS intervention can potentially be scaled up and disseminated across healthcare systems in low-and-middle income countries challenged with resource constraints to reduce poor outcomes among stroke survivors. 相似文献
23.
Emily Kilroy Laura Harrison Christiana Butera Aditya Jayashankar Sharon Cermak Jonas Kaplan Marian Williams Emily Haranin Susan Bookheimer Mirella Dapretto Lisa AzizZadeh 《Human brain mapping》2021,42(5):1532
A deficit in pre‐cognitively mirroring other people''s actions and experiences may be related to the social impairments observed in autism spectrum disorder (ASD). However, it is unclear whether such embodied simulation deficits are unique to ASD or instead are related to motor impairment, which is commonly comorbid with ASD. Here we aim to disentangle how, neurologically, motor impairments contribute to simulation deficits and identify unique neural signatures of ASD. We compare children with ASD (N = 30) to children with Developmental Coordination Disorder (DCD; N = 23) as well as a typically developing group (N = 33) during fMRI tasks in which children observe, imitate, and mentalize about other people''s actions. Results indicate a unique neural signature in ASD: during action observation, only the ASD group shows hypoactivity in a region important for simulation (inferior frontal gyrus, pars opercularis, IFGop). However, during a motor production task (imitation), the IFGop is hypoactive for both ASD and DCD groups. For all tasks, we find correlations across groups with motor ability, even after controlling for age, IQ, and social impairment. Conversely, across groups, mentalizing ability is correlated with activity in the dorsomedial prefrontal cortex when controlling for motor ability. These findings help identify the unique neurobiological basis of ASD for aspects of social processing. Furthermore, as no previous fMRI studies correlated brain activity with motor impairment in ASD, these findings help explain prior conflicting reports in these simulation networks. 相似文献
24.
Volz Kristen Wyckoff Emily Medina Tania Heudo Denmat Zeely Field Christiana LaRose Jessica Gorin Amy Leahey Tricia 《Journal of behavioral medicine》2021,44(6):853-859
Journal of Behavioral Medicine - Lower income is associated with greater stress, and stress has been shown to undermine treatment engagement and weight loss outcomes in face-to-face interventions.... 相似文献
25.
Napoli C Ackah E De Nigris F Del Soldato P D'Armiento FP Crimi E Condorelli M Sessa WC 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(19):12467-12470
The effects of chronic treatment with nitric oxide-containing aspirin (NO-aspirin, NCX-4016) in comparison with regular aspirin or placebo on the development of a chronic disease such as atherosclerosis were investigated in hypercholesterolemic low-density lipoprotein (LDL)-receptor-deficient mice. Male mice were assigned randomly to receive in a volume of 10 ml/kg either placebo (n = 10), 30 mg/kg/day NO-aspirin (n = 10), or 18 mg/kg/day of regular aspirin (n = 10). After 12 weeks of treatment, the computer-assisted imaging analysis revealed that NO-aspirin reduced the aortic cumulative lesion area by 39.8 +/- 12.3% compared with that of the placebo (P < 0.001). Regular aspirin did not reduce significantly aortic lesions (-5.1 +/- 2.3%) compared with the placebo [P = 0.867, not significant (NS)]. Furthermore, NO-aspirin reduced significantly plasma LDL oxidation compared with aspirin and placebo, as shown by the significant reduction of malondialdehyde content (P < 0.001) as well as by the prolongation of lag-time (P < 0.01). Similarly, systemic oxidative stress, measured by plasma isoprostanes, was significantly reduced by treatment with NCX-4016 (P < 0.05). More importantly, mice treated with NO-aspirin revealed by immunohistochemical analysis of aortic serial sections a significant decrease in the intimal presence of oxidation-specific epitopes of oxLDL (E06 monoclonal antibody, P < 0.01), and macrophages-derived foam cells (F4/80 monoclonal antibody, P < 0.05), compared with placebo or aspirin. These data indicate that enhanced NO release by chronic treatment with the NO-containing aspirin has antiatherosclerotic and antioxidant effects in the arterial wall of hypercholesterolemic mice. 相似文献
26.
27.
Anna Sessa Alessandra Mazzola Chetana Lim Mohammed Atif Juliana Pappatella Valerie Pourcher Olivier Scatton Filomena Conti 《World journal of gastroenterology : WJG》2020,26(44):7076-7084
BACKGROUNDCoronavirus disease (COVID) is a new and highly contagious infectious disease caused by the coronavirus (COVID-19 or severe acute respiratory syndrome coronavirus 2). There is limited data regarding the incidence and management of COVID-19 in immunocompromised patients’ post-transplantation. In the pre-COVID-19 era, these patients were already at an increased risk of developing opportunistic infections. These often manifested with atypical symptoms.CASE SUMMARYWe report another case of uneventful COVID-19 pneumonia in a 58-year old male who was 18 mo’ post liver transplantation. He received tacrolimus monotherapy since July 2019. The clinical manifestations included only epigastric pain radiating to the right hypochondrium, nausea and vomiting. He had no fevers, cough, shortness of breath, anosmia or dysgeusia even if the chest computed tomography scan revealed an extension of the multiple patchy ground-glass density shadows to the upper lobe of the left lung too. He was hospitalised and received a course of oral chloroquine (200 mg × 3 per day) for a period of 10 d. Interestingly, the COVID 19 infection was uneventful though there were no modifications to his tacrolimus dosing. He was successfully discharged. We performed subsequent follow-up via telemedicine.CONCLUSIONIn light of the current pandemic, it is even more important to identify how the liver recipient’s patients present and are managed, especially for immunosuppression treatment. 相似文献
28.
Maria Torner Adjmal Mangal Hubert Scharnagl Christian Jansen Michael Praktiknjo Alexander Queck Wenyi Gu Robert Schierwagen Jennifer Lehmann Frank E. Uschner Christiana Graf Christian P. Strassburg Javier Fernandez Tatjana Stojakovic Rainer Woitas Jonel Trebicka 《Liver international》2020,40(1):186-193
29.
Lown MT Munyombwe T Harrison W West RM Hall CA Morrell C Jackson BM Sapsford RJ Kilcullen N Pepper CB Batin PD Hall AS Gale CP;Evaluation of Methods Management of Acute Coronary Events 《The American journal of cardiology》2012,109(3):307-313
Risk assessment is central to the management of acute coronary syndromes. Often, however, assessment is not complete until the troponin concentration is available. Using 2 multicenter prospective observational studies (Evaluation of Methods and Management of Acute Coronary Events [EMMACE] 2, test cohort, 1,843 patients; and EMMACE-1, validation cohort, 550 patients) of unselected patients with acute coronary syndromes, a point-of-admission risk stratification tool using frontal QRS-T angle derived from automated measurements and age for the prediction of 30-day and 2-year mortality was evaluated. Two-year mortality was lowest in patients with frontal QRS-T angles <38° and highest in patients with frontal QRS-T angles >104° (44.7% vs 14.8%, p <0.001). Increasing frontal QRS-T angle-age risk (FAAR) scores were associated with increasing 30-day and 2-year mortality (for 2-year mortality, score 0 = 3.7%, score 4 = 57%; p <0.001). The FAAR score was a good discriminator of mortality (C statistics 0.74 [95% confidence interval 0.71 to 0.78] at 30 days and 0.77 [95% confidence interval 0.75 to 0.79] at 2 years), maintained its performance in the EMMACE-1 cohort at 30 days (C statistics 0.76 (95% confidence interval 0.71 to 0.8] at 30 days and 0.79 (95% confidence interval 0.75 to 0.83] at 2 years), in men and women, in ST-segment elevation myocardial infarction and non-ST-segment elevation myocardial infarction, and compared favorably with the Global Registry of Acute Coronary Events (GRACE) score. The integrated discrimination improvement (age to FAAR score at 30 days and at 2 years in EMMACE-1 and EMMACE-2) was p <0.001. In conclusion, the FAAR score is a point-of-admission risk tool that predicts 30-day and 2-year mortality from 2 variables across a spectrum of patients with acute coronary syndromes. It does not require the results of biomarker assays or rely on the subjective interpretation of electrocardiograms. 相似文献
30.
Baguet JP Chavanon O Sessa C Thony F Lantelme P Barone-Rochette G Mallion JM 《Journal of hypertension》2012,30(2):440-443
Hypertension, one of the major cardiovascular risk factors, promotes the formation of atheromatous lesions in the large arteries, including the aorta. It also favors aortic aneurysm and acute aortic syndrome such as aortic dissection or hematoma. In patients with aortic disease, beta-blockers and/or renin-angiotensin-aldosterone system inhibitors should be preferentially used to decrease blood pressure and improve arterial wall properties. 相似文献