Search results for "drug resistance"
showing 10 items of 953 documents
Dual disruption of aldehyde dehydrogenases 1 and 3 promotes functional changes in the glutathione redox system and enhances chemosensitivity in nonsm…
2020
AbstractAldehyde dehydrogenases (ALDHs) are multifunctional enzymes that oxidize diverse endogenous and exogenous aldehydes. We conducted a meta-analysis based on The Cancer Genome Atlas and Gene Expression Omnibus data and detected genetic alterations in ALDH1A1, ALDH1A3, or ALDH3A1, 86% of which were gene amplification or mRNA upregulation, in 31% of nonsmall cell lung cancers (NSCLCs). The expression of these isoenzymes impacted chemoresistance and shortened survival times in patients. We hypothesized that these enzymes provide an oxidative advantage for the persistence of NSCLC. To test this hypothesis, we used genetic and pharmacological approaches with DIMATE, an irreversible inhibito…
Evaluation of HIV-1 integrase resistance emergence and evolution in patients treated with integrase inhibitors
2020
Abstract Objectives This study evaluated the emergence of mutations associated with integrase strand transfer inhibitors (INSTI) resistance (INSTI-RMs) and the integrase evolution in human immunodeficiency virus type 1 (HIV-1) infected patients treated with this drug class. Methods The emergence of INSTI-RMs and integrase evolution (estimated as genetic distance between integrase sequences under INSTI treatment and before INSTI treatment) were evaluated in 107 INSTI-naive patients (19 drug-naive and 88 drug-experienced) with two plasma genotypic resistance tests: one before INSTI treatment and one under INSTI treatment. A logistic regression analysis was performed to evaluate factors associ…
Profiles of multidrug-resistant organisms among patients with bacteremia in intensive care units: an international ID-IRI survey
2021
Evaluating trends in antibiotic resistance is a requisite. The study aimed to analyze the profile of multidrug-resistant organisms (MDROs) among hospitalized patients with bacteremia in intensive care units (ICUs) in a large geographical area. This is a 1-month cross-sectional survey for blood-borne pathogens in 57 ICUs from 24 countries with different income levels: lower-middle-income (LMI), upper-middle-income (UMI), and high-income (HI) countries. Multidrug-resistant (MDR), extensively drug-resistant (XDR), or pan-drug-resistant isolates were searched. Logistic regression analysis determined resistance predictors among MDROs. Community-acquired infections were comparable to hospital-acq…
Transmission dynamics of HIV-1 subtype B in the Basque Country, Spain
2016
This work was aimed to study the HIV-1 subtype B epidemics in the Basque Country, Spain. 1727 HIV-1 subtype B sequences comprising protease and reverse transcriptase (PR/RT) coding regions, sampled between 2001 and 2008, were analyzed. 156 transmission clusters were detected by means of phylogenetic analyses. Most of them comprised less than 4 individuals and, in total, they included 441 patients. Six clusters comprised 10 or more patients and were further analyzed in order to study their origin and diversification. Four clusters included men who had unprotected homosexual sex (MSM), one group was formed by intravenous drug users (IDUs), and another included both IDUs and people infected th…
Predicting resistant etiology in hospitalized patients with blood cultures positive for Gram-negative bacilli
2018
Abstract Objective To develop a risk-scoring tool to predict multidrug-resistant (MDR) etiology in patients with bloodstream infections (BSI) caused by Gram-negative bacilli (GNB). Methods A prospective multicenter study analyzed patients with BSI hospitalized in 31 Internal Medicine wards in Italy from March 2012 to December 2012. Patients with BSI caused by MDR-GNB (non-susceptible to at least one agent in three antimicrobial categories) were compared to those with BSI due to susceptible GNB. A logistic regression to identify predictive factors of MDR-GNB was performed and the odds ratio (OR) were calculated. A score to predict the risk of MDR was developed. Results Of 533 BSI episodes, 2…
Non-neuronal cholinergic system contributes to corticosteroid resistance in chronic obstructive pulmonary disease patients
2016
Background: Inhaled corticosteroid (ICS) with long-acting beta-2 agonists is a well-documented combination therapy for chronic obstructive pulmonary disease (COPD) based on its additive anti-inflammatory properties. By contrast, the recommendation of ICS in combination with long-acting muscarinic antagonist (LAMA) is not evidence-based. In this study, neutrophils obtained from COPD patients were used to compare the anti-inflammatory effects of aclidinium bromide (a long-acting muscarinic antagonist) with corticosteroids and their potential additive effect. Methods: Human sputum and blood neutrophils were isolated from healthy individuals ( n = 37), patients with stable COPD ( n = 52) and th…
The Clinical Efficacy of Enzalutamide in Metastatic Prostate Cancer: Prospective Single-center Study
2017
Background/Aim: To evaluate the effectiveness of enzalutamide in Italian patients with hormone-refractory metastatic castration-resistant prostate cancer, progressing after chemotherapy with docetaxel plus prednisone. Patients and Methods: A total of 60 patients were enrolled. Reduction in serum prostate-specific antigen (PSA) was assessed as the primary endpoint, while reduction in pain, safety, progression-free survival and overall survival represented secondary endpoints. Results: Enzalutamide was well tolerated, with a manageable toxicity profile and a modest objective response rate. A considerable difference in serum levels of PSA before and after treatment was observed. A significant …
Both cholestatic and steatotic drugs trigger extensive alterations in the mRNA level of biliary transporters in rat hepatocytes: Application to devel…
2016
Disruption of the vectorial bile acid transport in the liver is a key feature of cholestatic drugs, although many causal and mechanistic aspects are still unknown. The aim of the present study was to explore if cholestatic drugs can repress or induce the expression of hepatic transporters. To this end, sandwich-cultured rat hepatocytes were treated with cholestatic and non-cholestatic (steatotic, non-hepatotoxic, etc.) drugs and the mRNA expression of 10 uptake and efflux biliary transporters was measured. Results evidenced that all cholestatic drugs cause extensive alterations in the mRNA expression of most biliary transporters. Surprisingly, nearly all steatotic drugs also affected the ex…
Prevalence of Single and Multiple Natural NS3, NS5A and NS5B Resistance-Associated Substitutions in Hepatitis C Virus Genotypes 1-4 in Italy
2018
AbstractNatural resistance-associated substitutions (RASs) are reported with highly variable prevalence across different HCV genotypes (GTs). Frequency of natural RASs in a large Italian real-life cohort of patients infected with the 4 main HCV-GTs was investigated. NS3, NS5A and NS5B sequences were analysed in 1445 HCV-infected DAA-naïve patients. Sanger-sequencing was performed by home-made protocols on 464 GT1a, 585 GT1b, 92 GT2c, 199 GT3a, 16 GT4a and 99 GT4d samples. Overall, 20.7% (301/1455) of patients showed natural RASs, and the prevalence of multiclass-resistance was 7.3% (29/372 patients analysed). NS3-RASs were particularly common in GT1a and GT1b (45.2-10.8%, respectively), mai…
Multiclass HCV resistance to direct-acting antiviral failure in real-life patients advocates for tailored second-line therapies
2017
Background & Aims: Despite the excellent efficacy of direct-acting antivirals (DAA) reported in clinical trials, virological failures can occur, often associated with the development of resistance-associated substitutions (RASs). This study aimed to characterize the presence of clinically relevant RASs to all classes in real-life DAA failures. Methods: Of the 200 virological failures that were analyzed in 197 DAA-treated patients, 89 with pegylated-interferon+ribavirin (PegIFN+RBV) and 111 without (HCV-1a/1b/1g/2/3/4=58/83/1/6/24/25; 56.8% treatment experienced; 65.5% cirrhotic) were observed. Sanger sequencing of NS3/NS5A/NS5B was performed by home-made protocols, at failure (N= 200) and w…