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1.
Einstein (Sao Paulo) ; 22: eAO0575, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38922219

RESUMO

OBJECTIVE: Currently programmed cell death protein 1 (PD-1) inhibitors in combination with other therapies are being evaluated to determine their efficacy in cancer treatment. However, the effect of PD-ligand (L) 1 expression on disease outcomes in stage III (EC III) non-small cell lung cancer is not completely understood. Therefore, this study aimed to assess the influence of PD-L1 expression on the outcomes of EC III non-small cell lung cancer. METHODS: This study was conducted on patients diagnosed with EC III non-small cell lung cancer who underwent treatment at a tertiary care hospital. PD-L1 expression was determined using immunohistochemical staining, all patients expressed PD-L1. Survival was estimated using the Kaplan-Meier method. Relationships between variables were assessed using Cox proportional regression models. RESULTS: A total of 49 patients (median age=69 years) with EC III non-small cell lung cancer and PD-L1 expression were evaluated. More than half of the patients were men, and most were regular smokers. The patients were treated with neoadjuvant chemotherapy, surgery, or sequential or combined chemotherapy and radiotherapy. The median progression-free survival of the entire cohort was 14.2 months, and the median overall survival was 20 months. There was no significant association between PD-L1 expression and disease progression, clinical characteristics, or overall survival. CONCLUSIONS: PD-L1 expression was not correlated with EC III non-small cell lung cancer outcomes. Whether these findings differ from the association with immune checkpoint inhibitors remains to be addressed in future studies.


Assuntos
Antígeno B7-H1 , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Estadiamento de Neoplasias , Humanos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/terapia , Masculino , Feminino , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Antígeno B7-H1/análise , Antígeno B7-H1/metabolismo , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Prognóstico , Estimativa de Kaplan-Meier , Imuno-Histoquímica , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Adulto
2.
Addict Biol ; 28(12): e13338, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38017638

RESUMO

Cues associated with smoking can induce relapse, which is likely driven by cue-induced neurobiological and physiological mechanisms. For instance, greater relapse vulnerability is associated with increases in cue-induced insula activation and heightened cortisol concentrations. Determining if there is a link between such cue-induced responses is critical given the need for biomarkers that can be easily measured in clinical settings and used to drive targeted treatment. Further, comprehensively characterising biological reactions to cues promises to aid in the development of therapies that address this specific relapse risk factor. To determine whether brain and cortisol responses to smoking cues are linked, this study recruited 27 nicotine-dependent tobacco-smoking individuals and acquired whole-brain functional activation during a cue reactivity task; salivary cortisol was measured before and after scanning. The results showed that increases in blood-oxygen-level-dependent activation in the right anterior insula and right dorsolateral prefrontal cortex (DLPFC) when viewing smoking versus neutral cues were positively correlated with a post-scan rise in salivary cortisol concentrations. These brain regions have been previously implicated in substance use disorders for their role in salience, interoception and executive processes. These findings show that those who have a rise in cortisol following smoking cue exposure also have a related rise in cue-induced brain reactivity, in brain regions previously linked with heightened relapse vulnerability. This is clinically relevant as measuring cue-induced cortisol responses is a more accessible proxy for assessing the engagement of cue-induced neurobiological processes associated with the maintenance of nicotine dependence.


Assuntos
Sinais (Psicologia) , Hidrocortisona , Fumar , Humanos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Nicotina , Recidiva
4.
Ecotoxicology ; 32(4): 502-511, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37118609

RESUMO

Small wild mammals have been used to measure the damage caused by exposure to oil-contaminated soil, including deer mice. However, the study of toxic effects of crude oil using oxidative damage biomarkers in the wild rodent Calomys laucha (Vesper mouse) is absent. This investigation aimed to evaluate the effects of acute exposure to contaminated soil with different concentrations of crude oil (0, 1, 2, 4 and 8% w/w), simulating an accidental spill, using oxidative stress biomarkers in the liver, kidneys, lungs, testes, paw muscle, and lymphocytes of C. laucha. Animals exposed to the contaminated soil showed increases in lipid peroxidation and protein carbonylation at the highest exposure concentrations in most organ homogenates analyzed and also in blood cells, but responses to total antioxidant capacity were tissue-dependent. These results showed that acute exposure to oil-contaminated soil caused oxidative damage in C. laucha and indicate these small mammals may be susceptible to suffer the impacts of such contamination in its occurrence region, threatening the species' survival.


Assuntos
Poluição por Petróleo , Petróleo , Animais , Poluição por Petróleo/efeitos adversos , Estresse Oxidativo , Biomarcadores , Petróleo/toxicidade , Solo , Mamíferos
5.
Int J Mol Sci ; 24(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36835617

RESUMO

Inactivation of the cyclin-dependent kinase inhibitor 2A (CDKN2A) gene is considerably more frequent in squamous cell lung cancer (SqCLC) than in other subtypes of lung cancer and may be a promising target for this histology. Here, we present the course of diagnosis and treatment of a patient with advanced SqCLC, harboring not only CDKN2A mutation but also PIK3CA amplification, Tumor Mutational Burden-High (>10 mutations/megabase), and a Tumor Proportion Score of 80%. After disease progression on multiple lines of chemotherapy and immunotherapy, he responded favorably to treatment with the CDK4/6i Abemaciclib and later achieved a durable partial response to immunotherapy rechallenge with a combination of anti-PD-1 and anti-CTLA-4, nivolumab, and ipilimumab.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Masculino , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma de Células Escamosas/tratamento farmacológico , Classe I de Fosfatidilinositol 3-Quinases/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Células Epiteliais , Imunoterapia , Ipilimumab/uso terapêutico , Neoplasias Pulmonares/genética , Mutação , Nivolumabe/uso terapêutico
6.
Clin Genitourin Cancer ; 21(2): e58-e69, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36266221

RESUMO

INTRODUCTION: Non-metastatic, castration-resistant prostate cancer (nmCRPC) is an important clinical stage of prostate cancer, prior to morbidity and mortality from clinical metastases. In particular, the introduction of novel androgen-receptor signaling inhibitors (ARSi) has changed the therapeutic landscape in nmCRPC. Given recent developments in this field, we update our recommendations for the management of nmCRPC. METHODS: A panel of 51 invited medical oncologists and urologists convened in May of 2021 with the aim of discussing and providing recommendations regarding the most relevant issues concerning staging methods, antineoplastic therapy, osteoclast-targeted therapy, and patient follow-up in nmCRPC. Panel members considered the available evidence and their practical experience to address the 73 multiple-choice questions presented. RESULTS: Key recommendations and findings include the reliance on prostate-specific antigen doubling time for treatment decisions, the absence of a clear preference between conventional and novel (i.e., positron-emission tomography-based) imaging techniques, the increasing role of ARSis in various settings, the general view that ARSis have similar efficacy. Panelists highlighted the slight preference for darolutamide, when safety is of greater concern, and a continued need to develop high-level evidence to guide the intensity of follow-up in this subset of prostate cancer. DISCUSSION: Despite the limitations associated with a consensus panel, the topics addressed are relevant in current practice, and the recommendations can help practicing clinicians to provide state-of-the-art treatment to patients with nmCRPC in Brazil and other countries with similar healthcare settings.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Neoplasias de Próstata Resistentes à Castração/diagnóstico , Neoplasias de Próstata Resistentes à Castração/terapia , Humanos , Masculino , Estadiamento de Neoplasias , Antineoplásicos/uso terapêutico , Antagonistas de Receptores de Andrógenos/uso terapêutico , Consenso , Brasil , Osteoclastos
7.
Genes (Basel) ; 13(10)2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36292694

RESUMO

Frantz tumors or solid pseudopapillary pancreatic neoplasm (SPN) are rare exocrine neoplasms that carry a favorable prognosis; they represent up to 3% of all tumors located in the region of the pancreas and have specific age and gender predispositions. In recent years, the rising curve of diagnosis is entitled to the evolution and access of diagnostic imaging. In this paper, we have retrospectively reviewed and described the clinical course of 40 patients with SPN from three institutions in Brazil, who had their diagnosis between 2005 and 2020, and analyzed the clinicopathological, genetic, and surgical aspects of these individuals. In accordance with the literature, most patients were women, 60% with unspecified symptoms at diagnosis, with tumors mainly located in the body and tail of the pancreas, of whom 70% underwent a distal pancreatectomy with sparing splenectomy as a standard procedure, and none of the cases have experienced recurrence to date. Surgery still remains the mainstay of treatment given the low metastatic potential, but more conservative approaches as observed in this cohort are evolving to become the standard of care. Herein, we present an in-depth analysis of cases focusing on the latest literature and report some of the smallest tumor cases in the literature. To our knowledge, this is the first report evaluating germline genetic testing and presenting a case of detected Li-Fraumeni syndrome.


Assuntos
Neoplasias Pancreáticas , Humanos , Feminino , Masculino , Brasil , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas/diagnóstico , Estudos Retrospectivos , Pancreatectomia/métodos , Pâncreas/patologia
8.
Sci Rep ; 12(1): 13592, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35948602

RESUMO

Neoadjuvant chemotherapy is considered a new treatment option for potentially resectable pancreatic cancer. However, data are not well established on overall survival and delaying surgery in resectable pancreatic cancer, as well as on those patients that ultimately cannot undergo surgery. We analyzed pancreatic cancer patients treated in a tertiary hospital from January 2016 to December 2020. Patients with resectable stage I and II pancreatic cancer were evaluated regarding surgery, neoadjuvant treatment, and other clinical demographics. The survival function was estimated using the Kaplan-Meier method, and the relationship between the variables of interest and the overall survival (OS) was assessed by adopting the proportional regression Cox models. A total of 216 patients were evaluated. 81 of them with resectable/borderline resectable disease and 135 with unresectable /metastatic disease at diagnosis. Median OS for stage I and II disease were 36 and 28 months, respectively. For resectable pancreatic cancer median OS was 28 months, for borderline resectable pancreatic cancer median OS was 11 months. Median OS for stage III (locally advanced) and stage IV (metastatic) were 10 and 7 months, respectively (p < 0.0001). Median OS of 9 months were obtained for patients with stage I and II that did not undergo surgery compared to 25 months in patients that underwent surgery in any time (p < 0.001). Comparing patients with localized disease, median OS for patients treated with upfront surgery was 28 months, compared to 15 months in patients treated with neoadjuvant approach (p = 0.04). Most patients that did not undergo surgery have decline of performance status or disease progression on neoadjuvant treatment. On multivariable analysis in pancreatic cancer stages I and II, including age, sex, borderline or resectable disease, CA 19-9, positive lymph nodes and neoadjuvant treatment, the surgery was the only factor associated with improved overall survival (p = 0.04). Upfront surgery should still be considered a standard of care approach for resectable pancreatic cancer. Biomarker driven studies and randomized trials with combination therapies are necessary to address neoadjuvant chemotherapy and delaying surgery in purely resectable pancreatic cancer.


Assuntos
Terapia Neoadjuvante , Neoplasias Pancreáticas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Humanos , Terapia Neoadjuvante/métodos , Pâncreas/patologia , Pancreatectomia/métodos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/cirurgia , Estudos Retrospectivos , Neoplasias Pancreáticas
9.
Lung Cancer ; 166: 94-97, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35245845

RESUMO

Comprehensive next-generation sequencing panels are leading to detection of rare gene fusion events. EFGR-RAD51 fusion is a rare oncogenic finding and clinical data for management of this condition is scarce. We report a widely metastatic non-small cell lung cancer in a never-smoker young male patient with sustained near-complete systemic and intracranial response to osimertinib, a third-generation EGFR tyrosine-kinase inhibitor (TKI). We also review the available data of other TKIs in this scenario and underscore the role of comprehensive molecular testing for NSCLC.


Assuntos
Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Acrilamidas , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Compostos de Anilina/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/genética , Fusão Gênica , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Masculino , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Rad51 Recombinase/genética
10.
Clinics (Sao Paulo) ; 76: e2498, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33503195

RESUMO

OBJECTIVES: To evaluate the efficacy and safety of sorafenib in elderly patients with advanced hepatocellular carcinoma (HCC). METHODS: We analyzed data from a cohort of patients with advanced HCC treated using systemic treatment according to the local institutional protocol. Patients were divided into two groups, Group A, individuals <70 years of age, and Group B, individuals 70 years of age or older at the time of treatment initiation. Efficacy, measured based on overall survival (OS) and time to treatment failure (TTF), and toxicity were compared between groups. RESULTS: A total of 238 patients with advanced HCC who received sorafenib between 2007 and 2018 were evaluated. The median age for Group A was 59.1 years and that for Group B 73.6 years. The major prognostic characteristics were balanced between the groups. There were no significant differences in OS between Group A (8.0 months, 95%CI 6.34-9.3) and Group B (9.0 months, 95%CI 5.38-12.62), p=0.433, or in TTF between Group A (3.0 months, 95%CI 2.39-3.60) and Group B (3.0 months, 95%CI 1.68-4.32), p=0.936. There were no significant differences between Groups A and B with respect to the incidence of adverse events or treatment discontinuation because of toxicity. CONCLUSION: Efficacy and safety of sorafenib did not differ significantly between younger and older patients with HCC. Our data suggest that age alone should not restrict clinical decision-making for patients with advanced HCC.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Idoso , Antineoplásicos/efeitos adversos , Carcinoma Hepatocelular/tratamento farmacológico , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Pessoa de Meia-Idade , Niacinamida/efeitos adversos , Compostos de Fenilureia/efeitos adversos , Prognóstico , Sorafenibe/efeitos adversos
11.
Clinics ; 76: e2498, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153964

RESUMO

OBJECTIVES: To evaluate the efficacy and safety of sorafenib in elderly patients with advanced hepatocellular carcinoma (HCC). METHODS: We analyzed data from a cohort of patients with advanced HCC treated using systemic treatment according to the local institutional protocol. Patients were divided into two groups, Group A, individuals <70 years of age, and Group B, individuals 70 years of age or older at the time of treatment initiation. Efficacy, measured based on overall survival (OS) and time to treatment failure (TTF), and toxicity were compared between groups. RESULTS: A total of 238 patients with advanced HCC who received sorafenib between 2007 and 2018 were evaluated. The median age for Group A was 59.1 years and that for Group B 73.6 years. The major prognostic characteristics were balanced between the groups. There were no significant differences in OS between Group A (8.0 months, 95%CI 6.34-9.3) and Group B (9.0 months, 95%CI 5.38-12.62), p=0.433, or in TTF between Group A (3.0 months, 95%CI 2.39-3.60) and Group B (3.0 months, 95%CI 1.68-4.32), p=0.936. There were no significant differences between Groups A and B with respect to the incidence of adverse events or treatment discontinuation because of toxicity. CONCLUSION: Efficacy and safety of sorafenib did not differ significantly between younger and older patients with HCC. Our data suggest that age alone should not restrict clinical decision-making for patients with advanced HCC.


Assuntos
Humanos , Pessoa de Meia-Idade , Idoso , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Antineoplásicos/efeitos adversos , Compostos de Fenilureia/efeitos adversos , Prognóstico , Niacinamida/efeitos adversos , Sorafenibe/efeitos adversos
12.
Clin Lung Cancer ; 21(6): e511-e515, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32389509

RESUMO

INTRODUCTION: We analyzed the prevalence of non-small-cell lung cancer (NSCLC) with a programmed cell death ligand 1 (PD-L1) tumor proportion score (TPS) of ≥ 50% and compared the results with the existing data from clinical trials and databases from other countries. MATERIALS AND METHODS: The Latin American Cooperative Oncology Group and Grupo Brasileiro de Oncologia Torácica performed a retrospective, cross-sectional study from August 2017 to April 2018. PD-L1 expression was collected from pathology reports from 5 laboratories in Brazil. All tests were sponsored by the pharmaceutical industry on request from the treating medical oncologist. PD-L1 expression was assessed by immunohistochemistry. The variables were summarized as absolute and relative frequencies or the median and interquartile range. Pearson's χ2 test was used to compare the TPS categories stratified by sex, age, and histologic type. All analyses were performed with SAS, version 9.4, and were deemed statistically significant at P < .05. RESULTS: A total of 1512 patients were included in the present study. Their median age was 66 years. Most patients were men (56.02%), and the most common histologic type was adenocarcinoma (58.04%); 109 tumors (11.31%) had EGFR mutations and 34 (3.64%) had ALK gene rearrangements. Overall, 56.54% had a PD-L1 TPS < 1%, 25.63% a TPS of 1% to 49%, and 17.83% a TPS of ≥ 50%. The factors associated with PD-L1 expression were histologic type (with adenocarcinoma samples having a greater proportion of TPS < 1%) and the laboratory that performed the test. CONCLUSION: The prevalence of high PD-L1 expression among the Brazilian NSCLC samples was lower than previously described in other countries, which could affect the number of patients who might be candidates for immunotherapy alone.


Assuntos
Adenocarcinoma de Pulmão/patologia , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Pulmonares/patologia , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/terapia , Idoso , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/terapia , Estudos Transversais , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Estudos Retrospectivos
13.
Behav Pharmacol ; 31(6): 565-573, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32209809

RESUMO

The α4ß2* nicotinic acetylcholine receptor (nAChR) subtypes are targeted for the development of smoking cessation aids, and the use of drug discrimination in mice provides a robust screening tool for the identification of drugs acting through nAChRs. Here, we established that the α4ß2* nAChR agonist epibatidine can function as a discriminative stimulus in mice. Male C57BL/6J mice discriminated epibatidine (0.0032 mg/kg, subcutaneously) and were tested with agonists varying in selectivity and efficacy for α4ß2* nAChRs. The discriminative stimulus effects of epibatidine were characterized with the nonselective, noncompetitive nicotinic antagonist mecamylamine, with the selective ß2-substype-containing nAChR antagonist dihydro-ß-erythroidine hydrobromide (DHßE), and the α7 antagonist methyllycaconitine (MLA). Nicotine (0.32-1.0 mg/kg, subcutaneously), the partial nAChR agonist cytisine (1.0-5.6 mg/kg, subcutaneously), and the α7 nAChR agonist N-[(3R)-1-azabicyclo[2.2.2]oct-3-yl]-4-chlorobenzamide (10-56 mg/kg, intraperitoneally) produced no more than 33% epibatidine-appropriate responding. The partial α4ß2* nAChR agonists varenicline and 2'-fluoro-3'-(4-nitro-phenyl)deschloroepibatidine produced 61 and 69% epibatidine-appropriate responding, respectively. DHßE and mecamylamine, but not MLA, significantly antagonized the discriminative stimulus effects of epibatidine. These results show that epibatidine may be trained as a discriminative stimulus in mice and has utility in elucidating the in-vivo pharmacology of α4ß2* nAChR ligands.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Aprendizagem por Discriminação/efeitos dos fármacos , Piridinas/farmacologia , Aconitina/análogos & derivados , Aconitina/farmacologia , Animais , Di-Hidro-beta-Eritroidina/farmacologia , Masculino , Mecamilamina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL
14.
Brain Behav ; 10(4): e01581, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32092237

RESUMO

OBJECTIVES: There is a long-standing interest in developing nicotinic acetylcholine receptor (nAChR) antagonists for concomitant use with nAChR agonists (e.g., nicotine replacement) as complementary smoking cessation aids. Previous studies demonstrate that daily nicotine treatment confers tolerance to some effects of nicotine, as well as cross-tolerance to other nAChR agonists. The current study assessed the extent to which antagonism of nicotine varies as a function of daily nicotine treatment. METHODS: Schedule-controlled responding and hypothermia were selected for study because they have been previously used to examine the pharmacology of nicotine, and both are sensitive to the development nicotine tolerance. The rate-decreasing and hypothermic effects of nicotine, as well as antagonism of those effects, were examined in C57BL/6J mice before, during treatment with, and after discontinuation of three daily injections of 1.78 mg/kg nicotine. The nonselective nAChR antagonist mecamylamine and the ß2 nAChR antagonist dihydro-ß-erythroidine (DHßE) were studied in combination with nicotine. RESULTS: The ED50 values of nicotine to produce rate-decreasing and hypothermic effects were, respectively, 0.44 and 0.82 mg/kg prior, 1.6 and 3.2 mg/kg during, and 0.74 and 1.1 mg/kg after discontinuation of daily nicotine treatment. Prior to daily nicotine treatment, mecamylamine decreased response rate and rectal temperature. However, during daily nicotine, mecamylamine (up to 5.6 mg/kg) only decreased rectal temperature. DHßE (up to 5.6 mg/kg) when studied prior to daily nicotine decreased rectal temperature, but that decrease was abolished during chronic nicotine treatment. Mecamylamine and DHßE antagonized the rate-decreasing and hypothermic effects of nicotine before and after daily nicotine; however, during daily nicotine, mecamylamine and DHßE antagonized only the hypothermic effects of nicotine. CONCLUSIONS: The differential antagonism of rate-decreasing and hypothermic effects implicates differential involvement of nAChR subtypes. The decreased capacity of mecamylamine and DHßE to antagonize nicotine during chronic nicotine treatment may indicate that their effectiveness as smoking cessations might vary as a function of nicotine tolerance and dependence.


Assuntos
Di-Hidro-beta-Eritroidina/farmacologia , Tolerância a Medicamentos , Mecamilamina/farmacologia , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Antagonistas Nicotínicos/farmacologia , Animais , Relação Dose-Resposta a Droga , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Abandono do Hábito de Fumar
15.
J Neurointerv Surg ; 12(8): 818-826, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31900352

RESUMO

BACKGROUND: Treatment of intracranial aneurysms with flow diverter stent (FDS) procedures can lead to caliber changes of jailed vessels. The reason some branches remain unchanged and others are affected by narrowing remains unknown. OBJECTIVE: To investigate the influence of resistance to flow from distal vasculature on stent-induced hemodynamic modifications affecting bifurcating vessels. MATERIALS AND METHODS: Radiological images and demographic data were acquired for 142 aneurysms treated with a FDS. Vascular resistance was estimated from patient-specific anatomic data. Correlation analysis was used to identify correspondence between anatomic data and clinical outcome. Computational Fluid Dynamics was performed on a typical patient-specific model to evaluate the influence of FDS on flow. Relevant hemodynamic variables along the bifurcating vessels were quantitatively analyzed and validated with in vitro data obtained using power Doppler ultrasound. RESULTS: Statistical analysis showed a correlation between clinical outcome and FDS resistance to flow considering overall jailed vessel vascular resistance (r=0.5, P<0.001). Computational predictions of blood flow showed that hemodynamics is minimally affected by FDS treatment in the ophthalmic artery. CONCLUSIONS: Jailed vessels are affected by narrowing when resistance to flow from the FDS constitutes a larger proportion of the overall vessel resistance to flow. This knowledge may contribute to better understanding of intracranial hemodynamics after a FDS procedure and reinforce indications for flow diversion in the treatment of intracranial aneurysms.


Assuntos
Constrição Patológica/diagnóstico por imagem , Aneurisma Intracraniano/diagnóstico por imagem , Stents , Hemodinâmica , Humanos , Hidrodinâmica , Aneurisma Intracraniano/cirurgia , Radiografia , Resultado do Tratamento
16.
Exp Clin Psychopharmacol ; 28(5): 517-526, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31789555

RESUMO

Chronic health problems associated with long-term nicotine use are the leading cause of preventable death in the United States. The use of tobacco products is 3-4 times greater among individuals with cocaine use disorder than that observed in the general population. This may reflect the propensity of nicotine to augment the reinforcing effects of cocaine. However, the mechanism of action of nicotine differs from that of cocaine, which presents a significant challenge for the development of pharmacotherapeutic interventions for the management of nicotine + cocaine polydrug abuse. Bupropion, an FDA-approved smoking cessation aid, has pharmacological actions at both monoamine transporters and nicotinic receptors, suggesting that it may be effective at decreasing nicotine + cocaine coabuse. Here, rhesus monkeys (n = 4) responded for food pellets and, separately, intravenous injections of nicotine, cocaine, or nicotine + cocaine mixtures under a second-order FR2(VR16:S) schedule of reinforcement during 7- to 10-day continuous treatment with saline or bupropion (1.0 and 1.8 mg/kg/hr). Results show that bupropion treatment dose-dependently decreased self-administration of nicotine combined with a low dose of cocaine (0.0032 mg/kg/inj); however, when the dose of cocaine in the mixture was higher (i.e., 0.01 mg/kg/inj), bupropion attenuated self-administration in only a subset of subjects. The effective dosage of bupropion increased responding for cocaine alone, nicotine alone, and for saline injections and significantly increased measures of daily activity. The apparent stimulant-like effects of bupropion at the dosage required to decrease cocaine + nicotine self-administration does not support its clinical use for the management of nicotine + cocaine polydrug abuse. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Bupropiona/administração & dosagem , Cocaína/administração & dosagem , Macaca mulatta/fisiologia , Nicotina/administração & dosagem , Agentes de Cessação do Hábito de Fumar/administração & dosagem , Animais , Estimulantes do Sistema Nervoso Central/uso terapêutico , Relação Dose-Resposta a Droga , Masculino , Reforço Psicológico , Autoadministração
17.
J Pharmacol Exp Ther ; 371(3): 624-632, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31527281

RESUMO

Nicotine can produce antinociception in preclinical pain models; however, the ability of nicotine to augment the antinociceptive effects of opioid agonists has not been investigated. The present experiments were conducted to determine how nicotine modifies the effects of opioid agonists differing in efficacy. Male squirrel monkeys responded for the delivery of milk under a fixed ratio 10 schedule of reinforcement. During the 30-second timeout period following each milk delivery, the subject's tail was immersed in 35, 50, 52, or 55°C water, and the latency to remove the tail was recorded. Dose-response functions for tail-withdrawal latency and operant performance were determined for fentanyl, oxycodone, buprenorphine, and nalbuphine alone and after treatment with nicotine. Excepting nalbuphine, all opioids produced dose-related disruptions in food-maintained responding and increases in tail-withdrawal latency at each water temperature. Nicotine did not exacerbate the behaviorally disruptive effects of the µ-opioids on operant performance but produced a significant mecamylamine-sensitive enhancement of the antinociceptive potency of each opioid. Failure of arecoline to augment the antinociceptive effects of oxycodone and antagonism by mecamylamine suggests this nicotine-induced augmentation of prescription opioid antinociception was nicotinic acetylcholine receptor (nAChR) mediated. This was reflected in leftward shifts in the antinociceptive dose-response curve of each opioid, ranging from 2- to 7-fold increases in the potency of oxycodone across all water temperatures to an approximately 70-fold leftward shift in the antinociceptive dose-response curve of nalbuphine at the lower and intermediate water temperatures. These results suggest that nicotine may enhance µ-opioid antinociceptive effects without concomitantly exacerbating their behaviorally disruptive effects. SIGNIFICANCE STATEMENT: Prescription opioids remain the most effective pain-management pharmacotherapeutics but are limited by their adverse effects. The present results indicate that nicotine enhances antinociceptive effects of various opioid agonists in nonhuman primates without increasing their disruptive effects on operant performance. These results suggest that nicotine might function as an opioid adjuvant for pain management by enabling decreased clinically effective analgesic doses of prescription opioids without exacerbating their adverse behavioral effects.


Assuntos
Analgésicos Opioides/farmacologia , Nicotina/farmacologia , Animais , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Masculino , Tempo de Reação/efeitos dos fármacos , Receptores Opioides mu/efeitos dos fármacos , Saimiri
18.
J. bras. nefrol ; 41(1): 89-94, Jan.-Mar. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1002420

RESUMO

Abstract Introduction: Vascular access (VA) in hemodialysis (HD) is essential to end-stage renal disease (ESRD) patients survival. Unfortunately, after some years in HD program, a significant number of patients may develop VA failure for many reasons. In this situation, arterial venous fistula (AVF) confection or catheters placement in traditional vascular sites (jugular, femoral or subclavian) are not feasible. In this scenario, translumbar tunneled dialysis catheter (TLDC) may be a salvage option. Objectives: To describe placement technic, complications, and patency of 12 TLDC. Methods: A retrospective study was performed to analyze 12 TLDC placement in an angiography suite using fluoroscopic guidance at the University Hospital of the Rio Grande do Norte Federal University from January 2016 to October 2017. The data collected of the total procedures performed consisted of demographic characteristics, success rates, observed complications, patient survival, and catheter patency. Results: All 12 TLDC were placed with success; there were only 2 significant periprocedure complications (major bleeding and extubation failure); 41.6% of patients presented a catheter-related first infection after 98 ± 72.1 (6-201) days, but catheter withdrawal was not necessary, mean total access patency was 315.5 (range 65 - 631) catheter-days, and catheter patency at 3, 6 and 12 months was 91 %, 75%, and 45%. Conclusion: TLDC is an option for patients with VA failure, improving survival and acting as a bridge for renal transplantation.


Resumo Introdução: O acesso vascular (AV) para hemodiálise (HD) é crucial para os pacientes portadores de doença renal crônica (DRC) estágio V. Infelizmente, com o passar dos anos, um percentual não desprezível desses enfermos evolui para falência de AV por diversos motivos, o que impossibilita a confecção de novas fístulas arteriovenosas (FAV) ou o implante de cateteres venosos centrais nos sítios de punções tradicionais. Nesse cenário, o implante de cateteres translombares para hemodiálise (CTLHD) em veia cava inferior ganha destaque como medida salvadora. Objetivos: Relatar uma série de 12 casos de implante de CTLHD, sua técnica de implante, patência e complicações. Métodos: Estudo retrospectivo que analisou 12 implantes de CTLHD por radiologista intervencionista no setor de hemodinâmica do Hospital Universitário da Universidade Federal do Rio Grande do Norte (UFRN), no período de janeiro/2016 a outubro/2017. Os dados coletados consistiram em: características demográficas da população estudada, taxa de sucesso, complicações observadas, sobrevida dos pacientes, patência do cateter e desfechos clínicos. Resultados: Todos os 12 CTLHD foram implantados e utilizados com sucesso; ocorreram apenas 2 complicações associadas ao procedimento (sangramento e falha na extubação); 41,6% dos pacientes apresentaram infecção relacionada ao cateter após 98 ± 72,1 dias (6-201 dias), mas não houve necessidade de remoção; e a patência foi de 315,5 cateteres-dia (65-631 dias). Conclusão: O CTLHD é uma opção para pacientes com falência de acesso vascular, prolongando a sobrevida dos pacientes e atuando como ponte para o transplante renal.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Doenças Vasculares/etiologia , Veia Cava Inferior/cirurgia , Cateterismo Venoso Central/métodos , Cateteres de Demora/efeitos adversos , Diálise Renal , Cateteres Venosos Centrais/efeitos adversos , Falência Renal Crônica/terapia , Região Lombossacral/irrigação sanguínea , Fluoroscopia , Estudos de Viabilidade , Estudos Retrospectivos , Fístula Arteriovenosa/complicações , Transplante de Rim , Resultado do Tratamento , Hemorragia/etiologia
19.
Behav Pharmacol ; 30(5): 412-421, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30398980

RESUMO

Varenicline is a smoking cessation pharmacotherapy with a presumed mechanism of action of partial efficacy at the α4ß2 nicotinic acetylcholine receptor (nAChR); however, the extent to which daily varenicline use leads to changes in nAChR sensitivity is unclear. This study examined the consequences of daily varenicline treatment on disruptions in operant responding (i.e. rate-decreasing effects) and hypothermia induced by administration of nicotine, epibatidine, cytisine, and cocaine in C57BL/6J mice. Furthermore, mecamylamine was used to assess the involvement of nAChRs in the effects of varenicline. Mice were trained under a fixed ratio 20 of milk reinforcement, and rectal temperatures were measured after 30 min following drug-administration. Varenicline, nicotine, epibatidine, and cytisine produced dose-dependent decreases in response rate and rectal temperature. Chronic varenicline (30 mg/kg) engendered tolerance to varenicline, but more cross-tolerance to nicotine, for both disruptions in operant responding and hypothermia. Cross-tolerance only developed to the hypothermic effects of epibatidine, and no cross-tolerance developed to any effects of cytisine and cocaine. In varenicline-tolerant mice, mecamylamine did not antagonize the effects of varenicline. The varying magnitudes of tolerance and cross-tolerance among effects and drugs are indicative of a nonuniform nAChR pharmacology in vivo.


Assuntos
Tolerância a Medicamentos/fisiologia , Receptores Nicotínicos/efeitos dos fármacos , Vareniclina/farmacologia , Alcaloides/farmacologia , Animais , Azocinas/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Cocaína/farmacologia , Condicionamento Operante/efeitos dos fármacos , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Antagonistas Nicotínicos/farmacologia , Piridinas/farmacologia , Quinolizinas/farmacologia , Receptores Nicotínicos/fisiologia , Reforço Psicológico , Abandono do Hábito de Fumar/métodos , Vareniclina/metabolismo
20.
Acta amaz ; 48(4): 338-346, Oct.-Dec. 2018. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1455374

RESUMO

Capirona decorticans (Rubiaceae) is popularly used to treat warts, wounds, mycoses and scabies, and is also a component of the Ayahuasca tea. Despite its popular use, the phytochemical and pharmacological research on this species is limited. Therefore, this work quantified phenolic compounds in the ethanolic extract (EE) and hydromethanolic fraction (FM) (406, 293 mgEAG g-1, respectively) from leaves of C. decorticans. We identified flavonoids by LC-MS/MS-MMR-ESI (apigenin, rutin, luteolin, miricetin, quercetin, quercetin-3--D-glucoside, quercetrin), and evaluated oxidative stress and mutagenic/antimutagenic effect of EE and FM through an in vivo experiment using Swiss mice and cyclophosphamide (CP) as an inducer of DNA damage and oxidative stress. Mice were pretreated for 15 consecutive days with EE or FM (250 mg kg-1) and then intraperitoneally injected with CP (25 mg kg-1). Carbonylated proteins, ascorbic acid, catalase and thiobarbituric acid-reactive substances were measured in hepatic and renal tissues. The mutagenic/antimutagenic effect was evaluated through the Micronucleus Test. Protein carbonylation in the liver of animals exposed to CP was reduced by FM. There was no significant effect on other markers of oxidative stress. The groups treated with the extracts showed a significant percentage reduction (EE = 96% and FM = 71%) in the frequency of micronucleated polychromatic erythrocytes induced by CP. EE showed mutagenicity when used alone. The EE and FM of C. decorticans leaves showed antioxidant potential equivalent to that observed in other species, did not cause oxidative stress, nor toxicity, and had a protective and antimutagenic effect, although the EE showed signs of mutagenicity.


Capirona decorticans (Rubiaceae) é popularmente usada para tratar verrugas, feridas, micoses e sarna, e como um componente do chá de Ayahuasca. Apesar do uso popular, são limitadas as pesquisas fitoquímicas e farmacológicas sobre a espécie. Portanto, este estudo quantificou compostos fenólicos no extrato etanólico (EE) e na fração hidrometanólica (FM) (406 e 293 mgEAG g-1, respectivamente) de folhas de C. decorticans. Identificamos flavonoides por LC-MS / MS-MMR-ESI (apigenina, rutina, luteolina, miricetina, quercetina, quercetina-3--D-glicosídeo, quercetrina), e avaliamos o estresse oxidativo e o efeito mutagênico/antimutagênico de EE e FM em um experimento in vivo utilizando camundongos Swiss e ciclofosfamida (CP) como um indutor de danos no DNA e estresse oxidativo. Os camundongos foram pré-tratados por 15 dias consecutivos com EE ou FM (250 mg kg-1) e injetados intraperitonealmente com CP (25 mg kg-1). Proteínas carboniladas, ácido ascórbico, catalase e substâncias reativas ao ácido tiobarbitúrico foram dosadas em tecidos hepáticos e renais. O efeito mutagênico/antimutagênico foi avaliado através do Teste de Micronúcleo. Houve carbonilação protéica no fígado de animais expostos à CP, que foi reduzida pela FM. Não houve efeito significativo sobre outros marcadores de estresse oxidativo. Os grupos tratados com os extratos apresentaram uma redução percentual significativa (EE = 96% e FM = 71%) na frequência de eritrócitos policromáticos micronucleados induzidos pela PC. O EE também apresentou mutagenicidade quando utilizado isoladamente. O EE e FM das folhas de C. decorticans apresentaram potencial antioxidante equivalente ao observado em outras espécies, não causaram estresse oxidativo, nem toxicidade, e tiveram efeito protetor e antimutagênico, embora a EE tenha apresentado mutagenicidade.


Assuntos
Masculino , Animais , Camundongos , Compostos Fenólicos/análise , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Rubiaceae/química , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Estresse Oxidativo , Modelos Animais
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