926 resultados para treatment resistance


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This article presents the design and implementation of a progressive resistance strength program adapted to prostate cancer. The initial model corresponds to the guide of the American College Sports Medicine Position Stand (ACSM, 2009). This program includes the most habitual symptoms related to the illness and its treatments. The study design is quasi-experimental. The sample is 33 subjects in treatment phase. Study variables are tumour classification TNM, anthropometric measures, resistance strength, hypertension, fatigue, incontinence, pain and quality of life. After 24 weeks a significant improvement on resistance strength capacity is observed. This result is more consistent in lower extremities. Also improves hypertension, urinary incontinence, pain and quality of life. As conclusion, the improvement of the quality of life is mediated by the functional and physical capacity of the ill person

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Trying to define the precise role played by insulin regulating the survival of brown adipocytes, we have used rat fetal brown adipocytes maintained in primary culture. The effect of insulin on apoptosis and the mechanisms involved were assessed. Different from the known effects of insulin as a survival factor, we have found that long-term treatment (72 h) with insulin induces apoptosis in rat fetal brown adipocytes. This process is dependent on the phosphatidylinositol 3-kinase/mammalian target of rapamycin/p70 S6 kinase pathway. Short-term treatment with the conditioned medium from brown adipocytes treated with insulin for 72 h mimicked the apoptotic effect of insulin. During the process, caspase 8 activation, Bid cleavage, cytochrome c release, and activation of caspases 9 and 3 are sequentially produced. Treatment with the caspase inhibitor, benzyloxycarbonyl-Val-Ala-Asp (Z-VAD), prevents activation of this apoptotic cascade. The antioxidants, ascorbic acid and superoxide dismutase, also impair this process of apoptosis. Moreover, generation of reactive oxygen species (ROS), probably through reduced nicotinamide adenine dinucleotide phosphate oxidases, and a late decrease in reduced glutathione content are produced. According to this, antioxidants prevent caspase 8 activation and Bid cleavage, suggesting that ROS production is an important event mediating this process of apoptosis. However, the participation of uncoupling protein-1, -2, and -3 regulating ROS is unclear because their levels remain unchanged upon insulin treatment for 72 h. Our data suggest that the prolonged hyperinsulinemia might cause insulin resistance through the loss of brown adipose tissue.

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Metabolic syndrome (MetS) is a disease composed of different risk factors such as obesity, type 2 diabetes or dyslipidemia. The prevalence of this syndrome is increasing worldwide in parallel with the rise in obesity. Nonalcoholic fatty liver disease (NAFLD) is now the most frequent chronic liver disease in western countries, affecting more than 30% of the general population. NAFLD encompasses a spectrum of liver manifestations ranging from simple steatosis to nonalcoholic steatohepatitis (NASH), fibrosis and cirrhosis, which may ultimately progress to hepatocellular carcinoma. There is accumulating evidence supporting an association between NAFLD and MetS. Indeed, NAFLD is recognized as the liver manifestation of MetS. Insulin resistance is increasingly recognized as a key factor linking MetS and NAFLD. Insulin resistance is associated with excessive fat accumulation in ectopic tissues, such as the liver, and increased circulating free fatty acids, which can further promote inflammation and endoplasmic reticulum stress. This in turn aggravates and maintains the insulin resistant state, constituting a vicious cycle. Importantly, evidence shows that most of the patients developing NAFLD present at least one of the MetS traits. This review will define MetS and NAFLD, provide an overview of the common pathophysiological mechanisms linking MetS and NAFLD, and give a perspective regarding treatment of these ever growing metabolic diseases.

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The Highly Active Antiretroviral Therapy (HAART) is the combination of at least three antiretroviral compounds. The combination purpose is to reduce the likelihood of drug resistance. However in the long-term the resistance to the first-line combination occurs and leads to treatment failure. Thus, a second-line and even a third-line regimen are recommended in the long run. [...] [P. 5] The two treatment alternatives under comparison: Tenofovir (300 mg) CO-formulated with Emtricitabine (200 mg) and Efavirenz (600 mg) currently known under the brand name Atripla (R) was introduced in July 2006 in the United States market. The excellent safety profile and ease of use make this combination a perfect first-line regimen in low-income settings. Therefore, this treatment option was recommended in WHO 2006 reviewed guidelines. Unfortunately, Tenofovir and Emtricitabine compounds are still costly and not yet widely available. For a matter of simplification this regimen is referred in this report as "the recent" therapy. Initially, we had in mind to consider the most frequently used first-line regimen in low-income countries (Stavudine / Larnivudme / Nevirapine) as a comparator for this economic evaluation. Unfortunately, according to the literature review results (see Annex 3); there was no data available comparing head to head the effectiveness of this regimen with the recent one. Instead, we selected a less frequently but commonly used first-line regimen in low-income countries as a comparator: Zidovudine, Lamivudine, Efavirenz. This combination has extensive experience in durability, safety and toxicity and seems to be an optimal choice for a first-line regimen according to the clinical trial group 384 team. Furthermore, Zidovudine, one of the compounds of this combination is now recommended as one of the preferred NNRTI [Non Nucleoside Reverse Transcriptase Inhibitors] options to be considered by countries instead of Stavudine (the most used NNRTI in limited-income countries). As this combination has been included in the WHO guidelines as a first-line therapy since 2003 when WHO launched the "3 by 5" scaling-up initiative, this combination of drugs is referred in this report as the "old" therapy. Objectives: The primary objective of this economic evaluation is to compare the two first-line HAARTs introduced above, in a low-income setting context. Both of these combinations are recommended by the 2006 WHO guidelines as potential first-line regimens. The secondary objective is to provide a simplified and comprehensible cost-effectiveness modeling tool in order to help policy makers, in resource-limited settings, make decisions about which first-line HAART to fund using the scarce resources available. [P. 6-7]

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Background: One of the problems in prostate cancer (CaP) treatment is the appearance of the multidrug resistance phenotype, in which ATP-binding cassette transporters such as multidrug resistance protein 1 (MRP1) play a role. Different localizations of the transporter have been reported, some of them related to the chemoresistant phenotype. Aim: This study aimed to compare the localization of MRP1 in three prostate cell lines (normal, androgen-sensitive, and androgen-independent) in order to understand its possible role in CaP chemoresistance. Methods: MRP1 and caveolae protein markers were detected using confocal microscopy, performing colocalization techniques. Lipid raft isolation made it possible to detect these proteins by Western blot analysis. Caveolae and prostasomes were identified by electron microscopy. Results: We show that MRP1 is found in lipid raft fractions of tumor cells and that the number of caveolae increases with malignancy acquisition. MRP1 is found not only in the plasma membrane associated with lipid rafts but also in cytoplasmic accumulations colocalizing with the prostasome markers Caveolin-1 and CD59, suggesting that in CaP cells, MRP1 is localized in prostasomes. Conclusion: We hypothesize that the presence of MRP1 in prostasomes could serve as a reservoir of MRP1; thus, taking advantage of the release of their content, MRP1 could be translocated to the plasma membrane contributing to the chemoresistant phenotype. The presence of MRP1 in prostasomes could serve as a predictor of malignancy in CaP

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Background: One of the problems in prostate cancer (CaP) treatment is the appearance of the multidrug resistance phenotype, in which ATP-binding cassette transporters such as multidrug resistance protein 1 (MRP1) play a role. Different localizations of the transporter have been reported, some of them related to the chemoresistant phenotype. Aim: This study aimed to compare the localization of MRP1 in three prostate cell lines (normal, androgen-sensitive, and androgen-independent) in order to understand its possible role in CaP chemoresistance. Methods: MRP1 and caveolae protein markers were detected using confocal microscopy, performing colocalization techniques. Lipid raft isolation made it possible to detect these proteins by Western blot analysis. Caveolae and prostasomes were identified by electron microscopy. Results: We show that MRP1 is found in lipid raft fractions of tumor cells and that the number of caveolae increases with malignancy acquisition. MRP1 is found not only in the plasma membrane associated with lipid rafts but also in cytoplasmic accumulations colocalizing with the prostasome markers Caveolin-1 and CD59, suggesting that in CaP cells, MRP1 is localized in prostasomes. Conclusion: We hypothesize that the presence of MRP1 in prostasomes could serve as a reservoir of MRP1; thus, taking advantage of the release of their content, MRP1 could be translocated to the plasma membrane contributing to the chemoresistant phenotype. The presence of MRP1 in prostasomes could serve as a predictor of malignancy in CaP

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Background: One of the problems in prostate cancer (CaP) treatment is the appearance of the multidrug resistance phenotype, in which ATP-binding cassette transporters such as multidrug resistance protein 1 (MRP1) play a role. Different localizations of the transporter have been reported, some of them related to the chemoresistant phenotype. Aim: This study aimed to compare the localization of MRP1 in three prostate cell lines (normal, androgen-sensitive, and androgen-independent) in order to understand its possible role in CaP chemoresistance. Methods: MRP1 and caveolae protein markers were detected using confocal microscopy, performing colocalization techniques. Lipid raft isolation made it possible to detect these proteins by Western blot analysis. Caveolae and prostasomes were identified by electron microscopy. Results: We show that MRP1 is found in lipid raft fractions of tumor cells and that the number of caveolae increases with malignancy acquisition. MRP1 is found not only in the plasma membrane associated with lipid rafts but also in cytoplasmic accumulations colocalizing with the prostasome markers Caveolin-1 and CD59, suggesting that in CaP cells, MRP1 is localized in prostasomes. Conclusion: We hypothesize that the presence of MRP1 in prostasomes could serve as a reservoir of MRP1; thus, taking advantage of the release of their content, MRP1 could be translocated to the plasma membrane contributing to the chemoresistant phenotype. The presence of MRP1 in prostasomes could serve as a predictor of malignancy in CaP

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Helicobacter pylori (H. pylori) is a gram negative bacteria that represents a considerable global burden in the world and is related to many gastrointestinal diseases (peptic ulcer, gastric MALT lymphoma or gastric cancer). Currently the triple standard therapy is less used as there is an increase of the clarithromycin resistance. Therefore patients have to receive several lines of treatment with the consequence of adverse events and the possibility to interrupt the treatment. This is why the main objective is to determine if making a culture and antibiogram to do a targeted treatment cause less adverse events with the same eradication than making an empirical treatment to eradicate H. pylori. The secondary objective is to determine the prevalence of resistance to clarithromycin in the province of GironaThis is a multicentre clinical trial without blinding; patients are selected by non-probabilistic sampling, with a total sample of 868 patients randomized in two equal groups of 434 patients in each group. The study will last 2 years. The endpoints will be to evaluate the adverse events and eradication of each group of patients. Also it will be evaluated the resistance to clarithromycin

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Pharmaceutical compounds have been detected in sewage treatment plant (STP) effluents, surface waters and, less frequently, in groundwater and drinking water, all over the world. Different sources are responsible for their appearance in the aquatic environment, however, it is widely accepted that the main sources of this type of pollutant are STP effluents. The adverse effects of pharmaceuticals in the environment include aquatic toxicity, development of resistance in pathogenic bacteria, genotoxicity and endocrine disruption. Thus, the discharge of these compounds to the environment in STP effluents should be minimized.

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Salmonella enterica – Fluorokinoloni- ja makrolidiresistenssimekanisimit Vakavia salmonellainfektioita on pitkään hoidettu fluorokinoloniantibiooteilla, kuten siprofloksasiinilla. Fluorokinolonien runsas käyttö niin ihmisillä kuin eläimilläkin on kuitenkin johtanut fluorokinoloniresistenttien salmonellakantojen lisääntymiseen. Vuoteen 2002 asti kaikki matalan tason fluorokinoloniresistenssiä ilmentävät salmonellakannat olivat resistenttejä nalidiksiinihapolle, joka on vanha ensimmäisen polven kinoloniantibiootti jota ei enää käytetä infektioiden hoidossa. Vuonna 2003 havaitsimme aivan uudentyyppisen resistenssifenotyypin salmonelloissa. Kaikki uuden fenotyypin kannat osoittivat matalaa fluorokinoloniresistenssiä (MIC ≥0.125 mg/L), mutta useat kannat olivat yllättäen aikaisempaa herkempiä nalidiksiinihapolle (MIC ≤32 mg/L). Ilmiöllä on suuri merkitys salmonellan antibioottiherkkyyksien määrittämisessä, sillä jos kanta on ollut nalidiksiinihapolle herkkä, sitä on pidetty herkkänä myös fluorokinoloneille. Väitöskirjatyössä määritettiin vuosina 2003–2007 Suomessa kerättyjen kotimaisten ja ulkomaalaisten S. enterica -kantojen fluorokinoloniresistenssiä sekä tutkittiin uuden salmonellafenotyypin epidemiologiaa ja resistenssimekanismeja. Lisäksi tutkittiin salmonellan hoidossa mahdollisesti käyttökelpoisen makrolidiantibioottijohdannaisen, atsitromysiinin tehoa salmonelloihin ja erityisesti matalaa fluorokinoloniresistenssiä ilmentäviin kantoihin. Tutkimuksessa havaittiin, että matalaa fluorokinoloniresistenssiä osoittavien salmonellakantojen määrä vähenee. Lasku oli voimakkainta Kaakkois-Aasiasta tuoduissa kannoissa. Uusi resistenssifenotyyppi on plasmidivälitteinen ja qnr-geenit olivat ainoa plasmidivälitteinen kinoloniresistenssimekanismi, joka kannoista löydettiin. Myöskään kromosomaalisten gyrA, gyrB ja parE -geenien QRDR-alueelta ei löydetty fluorokinoloniresistenssiä aiheuttavia mutaatioita. Transformaatiolla osoitettiin qnr-plasmidien olevan siirtyviä ja uusi resistenssifenotyyppi saatiin ilmennettyä myös herkässä vastaanottajakannassa. Nämä tulokset osoittavat, että vaikka S. enterican qnr-fenotyyppi on toistaiseksi levinnyt pääasiassa Kaakkois-Aasiaan, se siirtyy helposti bakteerista toiseen ja tulee todennäköisesti aiheuttamaan hoito-ongelmia myös muualla maailmassa. Uudentyyppinen qnr-fenotyyppi voi olla vaikea havaita perinteisellä herkkyysmäärityksellä. Siksi laboratorioissa tulisi aina määrittää sekä siprofloksasiiniettä nalidiksiinihappoherkkyydet. Atsitromysiinin osoitettiin olevan herkkyysmääritysten mukaan tehokas salmonelloja kohtaan mukaanlukien matala-asteista fluorokinoloniresistenssiä ilmentävät bakteerikannat.

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Resistance induction through the use of chemical inducers often results in physiological costs to the plant. In this study, induced resistance in cotton plants was evaluated with regard to physiological costs in a cultivar susceptible to Colletotrichum gossypii var. cephalosporioides (CNPA GO 2002 - 7997). Plants were cultivated in substrates with two levels of nitrogen and received two applications of acibenzolar-S-methyl (ASM), jasmonic acid (JA) and Agro-Mos® (AM) disease resistance inducers. Plant height (H), internodal length (IL), shoot fresh weight (SFW), root fresh weight (RFW), shoot dry weight (SDW) and root dry weight (RDW) were evaluated. The activity of the phenylalanine ammonia lyase (PAL) and peroxidase (POX) was also determined. The plants treated with ASM presented high physiological costs with an accentuated reduction in H, SFW and SDW, whereas those treated with JA exhibited a significant increase in SDW, and did not significantly differ from H and IL. In the potting mix supplemented with nitrogen, all inducers differed from the control treatment regarding to internodal length, whereas only ASM and AM presented a significant difference between one another in the potting mix without the addition of nitrogen. Significant correlations (P=0.05) were found for most of the variables analyzed, with greater correlations observed between SFW and SDW (0.94); IL and H (0.74); SFW and H (0.70); and SDW and H (0.70). ASM induced the least amount of PAL activity, significantly differing from the remaining treatments. Greater POX activity was observed in ASM, which significantly differed from the control. AM and JA, however, presented lower activity than the control with regard to these enzymes, and it was not possible to confirm induction resistance in these two treatments.

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Experiments were carried out in a growth chamber with controlled temperature and photoperiod to test two populations of Blumeria graminis f. sp. hordei from Guarapuava, Paraná State, and Passo Fundo, Rio Grande do Sul State, Brazil. Treatments consisted in application of the fungicide triadimenol (Baytan 150 SC®) at three rates of its commercial formulation: 150, 250, 350 mL/100 Kg barley seeds. The experiments were conducted separately in a growth chamber for each population, adopting the same temperature and photoperiod. For inoculation, pots containing barley seedlings colonized by the fungus were placed among the plots. After emergence of the first symptoms, the disease severity was assessed at two-day intervals. The experiments were repeated twice for each fungus population. Data were expressed as area under the disease progress curve and as powdery mildew control by comparing the severity after the fungicide treatments to that of control. Data were subjected to analysis of variance and regression analysis; the area under the disease progress curve was also calculated. Comparing the data obtained in the present study with those reported in the literature and the control, the maximum value of 26.1% is considered insufficient to prevent the damages caused by the disease. The control response to the fungicide rate was significant. We can conclude that there was a reduction in the sensitivity of both B. graminis f.sp. hordei populations to the fungicide triadimenol, which explains the control failure observed in barley farms.

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Rapid identification and resistance determination of pathogens in clinical specimens is vital for accurate treatment and monitoring of infectious diseases. Antimicrobial drug resistance is increasing globally and healthcare settings are facing this cost-intensive and even life-threatening problem. The incidence of resistant pathogens in Finland has remained relatively steady and manageable at least for the time being. DNA sequencing is the gold standard method for genotyping, mutation analysis, and identification of bacteria. Due to significant cost decrease in recent years, this technique is available to many research and clinical laboratories. Pyrosequencing technique, a rapid real-time DNA sequencing method especially suitable for analyzing fairly short stretches of DNA, was used in this study. Due to its robustness and versatility, pyrosequencing was applied in this study for identification of streptococci and detection of certain mutations causing antimicrobial resistance in different bacteria. Certain streptococcal species such as S. pneumoniae and S. pyogenes are significantly important clinical pathogens. S. pneumoniae causes e.g. pneumonia and otitis media and is one of the most important community-acquired pathogens. S. pyogenes, also known as group A streptococcus, causes e.g. angina and erysipelas. In contrast, the socalled alpha-haemolytic streptococci, such as S. mitis and S. oralis, belong to the normal microbiota, which are regarded to be non-pathogenic and are nearly impossible to identify by phenotypic methods. In this thesis, a pyrosequencing method was developed for identification of streptococcal species based on the 16S rRNA sequences. Almost all streptococcal species could be differentiated from one another by the developed method, including S. pneumoniae from its close relatives S. mitis and S. oralis . New resistance genes and their variants are constantly discovered and reported. In this study, new methods for detecting certain mutations causing macrolide resistance or extended spectrum beta-lactamase (ESBL) phenotype were developed. These resistance detection approaches are not only suitable for surveillance of mechanisms causing antimicrobial resistance but also for routine analysis of clinical samples particularly in epidemic settings. In conclusion, pyrosequencing was found to be an accurate, versatile, cost-effective, and rapid DNA sequencing method that is especially suitable for mutation analysis of short DNA fragments and identification of certain bacteria.

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Antimicrobial Resistance in Campylobacter jejuni and Campylobacter coli Campylobacters are a common cause of bacterial gastroenteritis worldwide, with Campylobacter jejuni and C. coli being the most common species isolated in human infections. If antimicrobial treatment is required, the drugs of choice at the moment are the macrolides and fluoroquinolones. In this thesis, the in vitro resistance profiles of the C. jejuni and C. coli strains were evaluated with emphasis on multidrug resistance. The aim was also to evaluate the different resistance mechanisms against the macrolides. Further, the disk diffusion method was compared to agar dilution method and its repeatability was evaluated, since it has been widely used for the susceptibility testing of campylobacters. The results of the present study showed that resistance to the fluoroquinolones is common in strains isolated from Finnish patients, but resistance to the macrolides is still rare. Multidrug resistance was associated with resistance to both ciprofloxacin and erythromycin. Among the available per oral drugs, least resistance was observed to coamoxiclav There was no resistance to the carbapenems. Sitafloxacin and tigecycline were in vitro highly effective towards Campylobacter species. A point mutation A2059G of the 23S rRNA gene was the main mechanism behind the macrolide resistance, whereas the efflux pumps did not seem to play an important role when a strain had A2059G mutation. A five amino acids insertion, which has not been described previously, in the ribosomal protein L22 of one highly-resistant C. jejuni strain without mutation in the 23S rRNA gene was also detected. Concerning the disk diffusion method, there was variation in the repeatability In conclusion, macrolides still appear to be the first-choice alternative for suspected Campylobacter enteritis. The in vitro susceptibilities found suggest that co-amoxiclav might be a candidate for clinical trials on campylobacteriosis, but in life-threatening situations, a carbapenem may be the drug of choice. More studies are needed on whether the disk diffusion test method could be improved or whether all susceptibilities of campylobacters should be done using a MIC based method.

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PURPOSE: To compare two single-agent chemotherapy (ChT) regimens evaluating, in first-line treatment, response and side effects and, in final single-agent treatment, the outcomes, among Brazilian patients with low-risk gestational trophoblastic neoplasia (GTN), according to International Federation of Gynecology and Obstetrics (FIGO) 2002. METHODS: Retrospective analysis of two concurrent cohorts with 194 low-risk GTN patients: from 1992 to 2012, as first-line treatment, 115 patients received 4 intramuscular doses of methotrexate alternated with 4 oral doses of folinic acid (MTX/FA) repetead every 14 days and, since 1996, 79 patients received an endovenous bolus-dose of actinomycin D (Act-D), biweekly. At GTN diagnosis, patient opinion was taken into consideration when defining the initial single-agent ChT regimen, and when there was resistance or toxicity to one regimen, the other drug was used preferentially. This study was approved by the Irmandade da Santa Casa de Misericórdia de Porto Alegre Ethical Committee. RESULTS: Both groups were clinically similar (p>0.05). In first-line treatments, frequency of complete response was similar (75.7% with MTX/FA and 67.1% with bolus Act-D); the number of ChT courses -median 3 (range: 1-10) with MTX/FA and 2 (range: 1-6) with bolus Act-D - and the time to remission -median 9 weeks (range: 2-16) with MTX/FA and 10 weeks (range: 2-16) with bolus Act-D) - were not different between the groups. In both groups, first-line side effects frequency were high but intensity was low; stomatitis was higher with MTX/FA (p<0.01) and nausea and vomit with Act-D (p<0.01). Final single-agent ChT responses were high in both groups (94.8% with MTX/FA and 83.5% with bolus Act-D; p<0.01) and 13% higher in the group initially treated with MTX/FA. Rates of hysterectomy and of GTN recurrence were low and similar. No patient died due to GTN. CONCLUSION: The two regimens had similar first-line ChT response. Final single-agent response rates were high and similar in both groups but the final single-agent remission rate was higher in the MTX/FA group.