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1.
Psychopharmacology (Berl) ; 240(10): 2201-2215, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37552291

RESUMO

RATIONALE: An important facet of cocaine addiction is a high propensity to relapse, with increasing research investigating factors that predispose individuals toward uncontrolled drug use and relapse. A personality trait linked to drug addiction is high sensation seeking, i.e., a preference for novel sensations/experiences. In an animal model of sensation seeking, operant novelty seeking predicts the acquisition of drug self-administration. OBJECTIVE: The primary goal of this research was to evaluate the hypothesis that sensitivity to the reinforcing effects of novel sensory stimuli predicts more intensive aspects of drug-taking behaviors, such as relapse. METHODS: Rats were first tested for Operant Novelty Seeking, during which responses resulted in complex visual/auditory stimuli. Next, rats were trained to respond to water/cocaine reinforcers signaled by a cue light. Finally, rats were exposed to extinction in the absence of discrete cues and subsequently tested in a single session of cue-induced reinstatement, during which active responses resulted in cues previously paired with water/cocaine delivery. RESULTS: The present study showed operant responses to produce novel sensory stimuli positively correlate with responding for cocaine during self-administration and during discrete cue-induced reinstatement, but no association with performance during extinction. A different pattern of associations was observed for a natural reward, in this case, water reinforcement. Here, the degree of novelty seeking also correlated with responding to water reinforcement and extinction responding; however, operant novelty seeking did not correlate with responding to water cues during testing of cue-induced reinstatement. Taken together, the incongruence of relationships indicates an underlying difference between natural and drug reinforcers. CONCLUSION: In summary, we found a reinforcer-dependent relationship between operant novelty seeking (i.e., sensation seeking) and responsivity to extinction and discrete cues signaling availability for cocaine (i.e., craving), demonstrating the validity of the operant novelty seeking model to investigate drug seeking and relapse.


Assuntos
Transtornos Relacionados ao Uso de Cocaína , Cocaína , Ratos , Masculino , Animais , Cocaína/farmacologia , Sinais (Psicologia) , Condicionamento Operante , Comportamento Exploratório , Extinção Psicológica/fisiologia , Recidiva , Autoadministração
2.
Am J Dermatopathol ; 45(8): 563-566, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37462206

RESUMO

ABSTRACT: Spindle cell lipoma (SCL) is a benign subcutaneous lipomatous neoplasm with a heterogeneous histologic appearance that varies greatly depending on the amount of fat, collagen, and myxoid stroma, which define the multiple subtypes of SCL, such as fat poor SCL, pseudoangiomatous SCL, and dendritic fibromyxolipoma. Cutaneous lymphoid hyperplasia is a spectrum of benign conditions characterized by reactive B-cell and T-cell cutaneous lymphocytic infiltrates. Cutaneous B-cell lymphoid hyperplasia is a heterogeneous group of non-neoplastic conditions that can be observed as reactive phenomena to infections, medications, allergens, or neoplasms and must be distinguished from cutaneous B-cell lymphomas. Here, we report a novel case of spindle cell lipoma, associated with B-cell primary lymphoid follicular hyperplasia, mixed within the tumor in a peculiar pattern, while discussing potential diagnostic pitfalls with low-grade B-cell lymphomas. This is the first report of such association in the literature.


Assuntos
Lipoma , Linfoma de Células B , Neoplasias de Tecido Conjuntivo , Neoplasias Cutâneas , Humanos , Hiperplasia , Lipoma/diagnóstico , Lipoma/patologia , Neoplasias Cutâneas/diagnóstico
3.
J Clin Oncol ; 39(12): 1317-1328, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33621109

RESUMO

PURPOSE: Patients with the activated B-cell-like (ABC) subtype of diffuse large B-cell lymphoma (DLBCL) historically showed inferior survival with standard rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). Phase II studies demonstrated that adding the immunomodulatory agent lenalidomide to R-CHOP improved outcomes in ABC-type DLBCL. The goal of the global, phase III ROBUST study was to compare lenalidomide plus R-CHOP (R2-CHOP) with placebo/R-CHOP in previously untreated, ABC-type DLBCL. METHODS: Histology and cell-of-origin type were prospectively analyzed by central pathology prior to random assignment and study treatment. Patients with ABC-DLBCL received lenalidomide oral 15 mg/d, days 1-14/21 plus standard R-CHOP21 versus placebo/R-CHOP21 for six cycles. The primary end point was progression-free survival (PFS) per independent central radiology review. RESULTS: A total of 570 patients with ABC-DLBCL (n = 285 per arm) were stratified by International Prognostic Index score, age, and bulky disease, and randomly assigned to R2-CHOP or placebo/R-CHOP. Baseline demographics were similar between arms. Most patients completed six cycles of treatment: 74% R2-CHOP and 84% placebo/R-CHOP. The most common grade 3/4 adverse events for R2-CHOP versus placebo/R-CHOP were neutropenia (60% v 48%), anemia (22% v 14%), thrombocytopenia (17% v 11%), and leukopenia (14% v 15%). The primary end point of PFS was not met, with a hazard ratio of 0.85 (95% CI, 0.63 to 1.14) and P = .29; median PFS has not been reached for either arm. PFS trends favoring R2-CHOP over placebo/R-CHOP were seen in patients with higher-risk disease. CONCLUSION: ROBUST is the first DLBCL phase III study to integrate biomarker-driven identification of eligible ABC patients. Although the ROBUST trial did not meet the primary end point of PFS in all patients, the safety profile of R2-CHOP was consistent with individual treatments with no new safety signals.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Lenalidomida/administração & dosagem , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Feminino , Humanos , Lenalidomida/efeitos adversos , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Rituximab/administração & dosagem , Rituximab/efeitos adversos , Vincristina/administração & dosagem , Vincristina/efeitos adversos , Adulto Jovem
5.
Clin Cancer Res ; 23(15): 4127-4137, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28381416

RESUMO

Purpose: Randomized, multicenter, open-label, phase 2/3 trial investigating lenalidomide versus investigator's choice (IC) in relapsed/refractory diffuse large B-cell lymphoma (DLBCL).Experimental Design: Patients with DLBCL who received ≥2 prior therapies were stratified by DLBCL subtype [germinal center B-cell (GCB) vs. non-GCB; determined by immunohistochemistry (IHC)] and then randomized 1:1 to lenalidomide (25 mg/day, 21 days of 28-day cycle) or IC (gemcitabine, rituximab, etoposide, or oxaliplatin). Crossover to lenalidomide was permitted for IC-treated patients with radiologically confirmed progressive disease. The primary endpoint was overall response rate (ORR). Progression-free survival (PFS), overall survival, and subtype analysis [GCB vs. activated B-cell (ABC)] using gene expression profiling (GEP) were exploratory endpoints.Results: Stage 1: 102 DLBCL patients (by IHC: non-GCB, n = 54; GCB, n = 48) received ≥1 dose of lenalidomide or IC. Hematologic treatment-emergent adverse events with lenalidomide versus IC included neutropenia (42.6%; 36.4%), anemia (33.3%; 47.3%), thrombocytopenia (24.1%; 43.6%), and leukopenia (5.6%; 12.7%), respectively. Overall, lenalidomide-treated patients had an ORR of 27.5% versus 11.8% in IC (ORRs were similar regardless of IHC-defined DLBCL subtype). Median PFS was increased in patients receiving lenalidomide (13.6 weeks) versus IC (7.9 weeks; P = 0.041), with greater improvements in non-GCB patients (15.1 vs. 7.1 weeks, respectively; P = 0.021) compared with GCB (10.1 vs. 9.0 weeks, respectively; P = 0.550).Conclusions: The clinical benefit of lenalidomide monotherapy in DLBCL patients was more evident in the non-GCB subtype. Exploratory analyses suggest that this preferential benefit was more pronounced in the GEP-defined ABC population, demonstrating a need for additional studies of lenalidomide in DLBCL using GEP subtyping. Clin Cancer Res; 23(15); 4127-37. ©2017 AACR.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Prognóstico , Talidomida/análogos & derivados , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Etoposídeo/administração & dosagem , Feminino , Humanos , Estimativa de Kaplan-Meier , Lenalidomida , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Modelos de Riscos Proporcionais , Rituximab/administração & dosagem , Talidomida/administração & dosagem , Talidomida/efeitos adversos , Resultado do Tratamento , Gencitabina
6.
Physiol Biochem Zool ; 86(2): 193-204, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23434779

RESUMO

Life history integration of the defense response was investigated at intra- and interspecific levels in land snails of the family Helicidae. Two hypotheses were tested: (i) fitness consequences of defense responses are closely related to life history traits such as size at maturity and life span; (ii) different pathways of the immune response based on "nonspecific" versus "specific" responses may reflect different defense options. Relevant immune responses to a challenge with E. coli were measured using the following variables: blood cell density, cellular or plasma antibacterial activity via reactive oxygen species (ROS) level, and bacterial growth inhibition. The results revealed that the largest snails did not exhibit the strongest immune response. Instead, body mass influenced the type of response in determining the appropriate strategy. Snails with a higher body mass at maturity had more robust plasma immune responses than snails with a lower mass, which had greater cell-mediated immune responses with a higher hemocyte density. In addition, ROS appeared also to be a stress mediator as attested by differences between sites and generations for the same species.


Assuntos
Caramujos/fisiologia , Animais , Tamanho Corporal , Escherichia coli/fisiologia , Hemócitos/fisiologia , Imunidade Celular , Longevidade , Espécies Reativas de Oxigênio/metabolismo , Caramujos/imunologia , Especificidade da Espécie
8.
Dermatol Online J ; 17(9): 15, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21971280

RESUMO

TNF-α inhibitors, including adalimumab, are increasingly used in the management of inflammatory cutaneous, gastrointestinal, and rheumatologic diseases. An untoward class effect of these medications is the development of new-onset psoriasis, particularly in patients treated for rheumatologic diseases without any personal or family history of cutaneous psoriasis. We report two patients that developed cutaneous and histologic changes consistent with psoriasis while receiving treatment with adalimumab for inflammatory arthridities: one patient with Crohn disease and ankylosing spondylitis who tolerated adalimumab for 15 months before developing psoriasis and another patient with rheumatoid arthritis who developed psoriasis 3 years after starting adalimumab. Both patients experienced rapid resolution of their psoriasis after discontinuation of adalimumab.


Assuntos
Anti-Inflamatórios/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Psoríase/induzido quimicamente , Adalimumab , Adulto , Artrite Reumatoide/tratamento farmacológico , Doença de Crohn/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Espondilite Anquilosante/tratamento farmacológico
11.
PLoS One ; 6(5): e20122, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21647445

RESUMO

Many bioinformatic databases and applications focus on a limited domain of knowledge federating links to information in other databases. This segregated data structure likely limits our ability to investigate and understand complex biological systems. To facilitate research, therefore, we have built HIVToolbox, which integrates much of the knowledge about HIV proteins and allows virologists and structural biologists to access sequence, structure, and functional relationships in an intuitive web application. HIV-1 integrase protein was used as a case study to show the utility of this application. We show how data integration facilitates identification of new questions and hypotheses much more rapid and convenient than current approaches using isolated repositories. Several new hypotheses for integrase were created as an example, and we experimentally confirmed a predicted CK2 phosphorylation site. Weblink: [http://hivtoolbox.bio-toolkit.com].


Assuntos
Biologia Computacional/métodos , Bases de Dados de Proteínas , HIV-1 , Internet , Integração de Sistemas , Sítios de Ligação , Caseína Quinase II/metabolismo , Integrase de HIV/química , Integrase de HIV/metabolismo , HIV-1/enzimologia , HIV-1/fisiologia , Modelos Moleculares , Fosforilação , Multimerização Proteica , Estrutura Quaternária de Proteína , Interface Usuário-Computador
12.
Physiol Biochem Zool ; 84(2): 212-21, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21460532

RESUMO

Immune defenses have been shown to be heavily involved in the evolution of physiological trade-offs. In this study, we compared the internal defense systems in two subspecies of the land snail Cornu aspersum that exhibit contrasting life-history strategies. The "fast-living" Cornu aspersum subsp. aspersa is widespread throughout the world, especially in ecosystems disturbed by man, whereas natural populations of the giant Cornu aspersum subsp. maxima, characterized by a longer life span, are present only in north Africa. Snails were experimentally challenged with Escherichia coli; the measurements used to assess their internal defense for cell- and humoral-mediated immune responses were bacterial clearance, hemocyte density, reactive oxygen species (ROS) production, and plasma antibacterial activity. Both subspecies showed a similar ability to clear bacteria from their hemolymph; however, they varied in the robustness of different individual immune components. Cornu aspersum aspersa had higher ROS activity than did C. a. maxima and lower plasma bactericidal activity. These results suggest that ecological factors can sculpt the immune response. One interpretation is that shorter life span selects for immune defenses such as ROS that, although effective, can cause long-term damage. Such different immune patterns obviously entail various costs involved in the strong intraspecific variation of life-history trade-offs we previously observed. We also have to consider that such variation might be related to intraspecific differences in the relative strength of resistance and tolerance mechanisms.


Assuntos
Caramujos/imunologia , Animais , Escherichia coli/imunologia , Hemócitos/citologia , Hemócitos/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Caramujos/metabolismo , Caramujos/microbiologia
17.
Cell Tissue Res ; 333(1): 147-58, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18431599

RESUMO

The disturbance of plasma membrane carbohydrates and of lipopolysaccharide (LPS) ligands in relation to cytoskeletal transformations of haemocytes has been investigated after chronic exposure of pond snails (Lymnaea stagnalis) to the peroxidizing toxicant fomesafen. Neither of the two lectins used (concanavalin A and wheat germ agglutinin) showed any binding modification after incubation of the snails in the presence of the toxicant. However, after exposure of the snails to fomesafen, a clear and persistent reduction in LPS labelling of haemocytes occurred. The actin cytoskeleton of the same cells also appeared to be sensitive to the toxicant. The reduction in LPS-binding sites was related to actin staining, leading to the hypothesis that LPS ligands and actin could be similarly modulated by the toxicant. Damaged cells showed non-adherent membrane portions with reduced filopodial extrusions, exhibiting a smooth surface free of microvilli. These changes could lower the spreading and adhesion of the cells and could therefore account for the loss in their phagocytic capabilities.


Assuntos
Lymnaea/efeitos dos fármacos , Lymnaea/imunologia , Fagocitose/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Actinas/metabolismo , Animais , Benzamidas/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fluoresceína-5-Isotiocianato/metabolismo , Corantes Fluorescentes/metabolismo , Hemócitos/efeitos dos fármacos , Hemócitos/imunologia , Hemócitos/metabolismo , Hemócitos/ultraestrutura , Herbicidas/toxicidade , Lectinas/imunologia , Lectinas/metabolismo , Lectinas/farmacologia , Lymnaea/metabolismo , Fagocitose/imunologia , Faloidina/metabolismo , Rodaminas/metabolismo , Fatores de Tempo
18.
Cell Tissue Res ; 328(2): 431-41, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17252246

RESUMO

The effects of a xenobiotic on the circulating haemocytes of Lymnaea stagnalis were investigated after short-term (24 h, 96 h) and long-term (504 h) exposure of snails to environmental concentrations. Fomesafen, a pro-oxidant generator led to the activation of the haemocyte apoptotic program by promoting reactive oxygen species (ROS). Cells entering apoptosis underwent a series of events, both on the plasma membrane and in the mitochondria; these events were quantified by flow cytofluorometry. The data showed a loss of mitochondrial transmembrane potential (Deltapsim), which was dose-dependent and time-dependent and related to an increased release of superoxide anions. The phosphatidylserine that was exposed at the outer plasma membrane was not related to the disruption of either ROS or Deltapsim but was strongly correlated with the haemocyte concentration (total haemocyte count). This cascade of apoptotic processes occurred in a dose-independent manner and was not strengthened over time. The increase of circulating haemocytes depended upon the life span of the cells and might have reflected either facilitated cell turn-over or the accompanying presence of haemocytes phagocytosing apoptotic cells.


Assuntos
Apoptose/efeitos dos fármacos , Benzamidas/toxicidade , Hemócitos/citologia , Imunidade/efeitos dos fármacos , Lymnaea/efeitos dos fármacos , Lymnaea/imunologia , Animais , Anexina A5/metabolismo , Contagem de Células Sanguíneas , Citometria de Fluxo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
19.
Environ Pollut ; 146(2): 420-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16930795

RESUMO

Responses of circulating hemocytes were studied in Lymnaea stagnalis exposed to 10, 30, 90, and 270 microg/L fomesafen for 24 and 504 h. Flow cytometry was used to quantify fomesafen-induced production of reactive oxygen species (ROS), phagocytic activity on Escherichia coli, and oxidative burst when hemocytes were challenged by E. coli or phorbol 12-myristate-13-acetate (PMA). Lysosomal membrane damage was assessed, using the neutral-red retention time (NRRT) assay. Exposure to fomesafen for 24 h resulted in increase in ROS levels and decreases in phagocytosis and the oxidative burst in PMA-stimulated hemocytes. After 504 h, intracellular levels of ROS returned to normal, but phagocytosis of E. coli was still inhibited and the associated oxidative burst significantly reduced. After both durations of exposure, decreases of NRRT indicated that lysosome membrane fragility increased with fomesafen concentration. Potential implications for the health and survival of the snails and consequences on populations are discussed.


Assuntos
Benzamidas/toxicidade , Hemócitos/efeitos dos fármacos , Herbicidas/toxicidade , Lymnaea/imunologia , Animais , Relação Dose-Resposta a Droga , Escherichia coli/imunologia , Hemócitos/imunologia , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/imunologia , Lymnaea/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/imunologia , Estresse Oxidativo/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Acetato de Tetradecanoilforbol/imunologia , Fatores de Tempo
20.
Environ Pollut ; 127(2): 303-11, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14568729

RESUMO

Immunotoxicological effects of environmentally relevant concentrations (10, 23, 50, 100 microg/l) of atrazine were studied in Lymnaea stagnalis. Individual hemolymph sampling was performed at 0, 24, 48, 72, 96, 168, 336, 504 and 672 h during exposure. Every atrazine concentration induced a significant increase in the mean number of circulating hemocytes, without any concentration-response relation. A peak (1.6-fold increase) of hemocyte density was observed after 96 h of exposure. After 504 h, the number of hemocytes remained higher only in the snails exposed to the two highest concentrations. Granulocytes contributed most to the increase in hemocyte density in herbicide-exposed snails. Both short- (24 and 96 h) and long-term (504 h) exposures resulted in significant inhibition of hemocyte phagocytic activity upon E. coli. Over the long-term, phagocytosis recovered for the two lowest concentrations. After 504 h of exposure, every herbicide level resulted in a significant reduction of reactive oxygen species production in E. coli-stimulated hemocytes, which was not observed for short-term exposures.


Assuntos
Atrazina/toxicidade , Lymnaea/efeitos dos fármacos , Resíduos de Praguicidas/toxicidade , Fagocitose/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Relação Dose-Resposta a Droga , Escherichia coli/imunologia , Hemócitos/efeitos dos fármacos , Hemócitos/fisiologia , Lymnaea/imunologia , Lymnaea/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Explosão Respiratória/efeitos dos fármacos
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