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1.
Bull World Health Organ ; 92(2): 108-16, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24623904

RESUMO

OBJECTIVE: To determine whether national drug control laws ensure that opioid drugs are available for medical and scientific purposes, as intended by the 1972 Protocol amendment to the 1961 Single Convention on Narcotic Drugs. METHODS: The authors examined whether the text of a convenience sample of drug laws from 15 countries: (i) acknowledged that opioid drugs are indispensable for the relief of pain and suffering; (ii) recognized that government was responsible for ensuring the adequate provision of such drugs for medical and scientific purposes; (iii) designated an administrative body for implementing international drug control conventions; and (iv) acknowledged a government's intention to implement international conventions, including the Single Convention. FINDINGS: Most national laws were found not to contain measures that ensured adequate provision of opioid drugs for medical and scientific purposes. Moreover, the model legislation provided by the United Nations Office on Drugs and Crime did not establish an obligation on national governments to ensure the availability of these drugs for medical use. CONCLUSION: To achieve consistency with the Single Convention, as well as with associated resolutions and recommendations of international bodies, national drug control laws and model policies should be updated to include measures that ensure drug availability to balance the restrictions imposed by the existing drug control measures needed to prevent the diversion and nonmedical use of such drugs.


Assuntos
Analgésicos Opioides/provisão & distribuição , Controle de Medicamentos e Entorpecentes/legislação & jurisprudência , Internacionalidade , Humanos , Projetos Piloto
2.
PLoS Biol ; 7(6): e1000121, 2009 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-19492080

RESUMO

Recent evidence suggests that many malignancies, including breast cancer, are driven by a cellular subcomponent that displays stem cell-like properties. The protein phosphatase and tensin homolog (PTEN) is inactivated in a wide range of human cancers, an alteration that is associated with a poor prognosis. Because PTEN has been reported to play a role in the maintenance of embryonic and tissue-specific stem cells, we investigated the role of the PTEN/Akt pathway in the regulation of normal and malignant mammary stem/progenitor cell populations. We demonstrate that activation of this pathway, via PTEN knockdown, enriches for normal and malignant human mammary stem/progenitor cells in vitro and in vivo. Knockdown of PTEN in normal human mammary epithelial cells enriches for the stem/progenitor cell compartment, generating atypical hyperplastic lesions in humanized NOD/SCID mice. Akt-driven stem/progenitor cell enrichment is mediated by activation of the Wnt/beta-catenin pathway through the phosphorylation of GSK3-beta. In contrast to chemotherapy, the Akt inhibitor perifosine is able to target the tumorigenic cell population in breast tumor xenografts. These studies demonstrate an important role for the PTEN/PI3-K/Akt/beta-catenin pathway in the regulation of normal and malignant stem/progenitor cell populations and suggest that agents that inhibit this pathway are able to effectively target tumorigenic breast cancer cells.


Assuntos
Mama , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Células-Tronco/metabolismo , beta Catenina/metabolismo , Animais , Mama/citologia , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Células-Tronco/patologia , beta Catenina/genética
3.
Environ Toxicol Chem ; 41(3): 758-770, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35112731

RESUMO

Mercury (Hg) and radiocesium (137 Cs) are well-known environmental contaminants with the potential to impact the health of humans and wildlife. Snakes have several characteristics conducive to studying environmental contamination but have rarely been included in the monitoring of polluted sites. We investigated the bioaccumulation of Hg and 137 Cs and associations with sublethal effects (standard metabolic rate [SMR] and hemoparasite infections) in Florida green watersnakes (Nerodia floridana). We captured 78 snakes from three former nuclear cooling reservoirs on the US Department of Energy's Savannah River Site in South Carolina (USA). For captured snakes, we (1) determined whole-body 137 Cs, (2) quantified total Hg (THg) using snake tail clips, (3) conducted hemoparasite counts, and (4) measured the SMR. We used multiple regression models to determine associations among snake body size, capture location, sex, tail THg, whole-body 137 Cs, Hepatozoon spp. prevalence and parasitemia, and SMR. Average whole-body 137 Cs (0.23 ± 0.08 Becquerels [Bq]/g; range: 0.00-1.02 Bq/g) was correlated with snake body size and differed significantly by capture site (Pond B: 0.67 ± 0.05 Bq/g; Par Pond: 0.10 ± 0.02 Bq/g; Pond 2: 0.03 ± 0.02 Bq/g). Tail THg (0.33 ± 0.03 mg/kg dry wt; range: 0.16-2.10 mg/kg) was significantly correlated with snake body size but did not differ by capture site. We found no clear relationship between SMR and contaminant burdens. However, models indicated that the prevalence of Hepatozoon spp. in snakes was inversely related to increasing whole-body 137 Cs burdens. Our results indicate the bioaccumulation of Hg and 137 Cs in N. floridana and further demonstrate the utility of aquatic snakes as bioindicators. Our results also suggest a decrease in Hepatozoon spp. prevalence related to increased burdens of 137 Cs. Although the results are intriguing, further research is needed to understand the dynamics between 137 Cs and Hepatozoon spp. infections in semiaquatic snakes. Environ Toxicol Chem 2022;41:758-770. © 2022 SETAC.


Assuntos
Mercúrio , Animais , Biomarcadores Ambientais , Monitoramento Ambiental , Florida , Humanos , Mercúrio/análise , Rios , Serpentes/metabolismo
4.
Mol Oncol ; 7(3): 680-92, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23538216

RESUMO

BACKGROUND: Enumeration of circulating tumor cells (CTC) from whole blood permits monitoring of patients with breast carcinoma. Analysis of apoptosis & Bcl-2 expression in CTC might add additional prognostic and predictive information. We estimated the degree of these markers in CTC from patients being treated for metastatic breast cancer. METHODS: Eighty-three evaluable patients initiating a new therapy for metastatic breast cancer were enrolled. Whole blood was collected at baseline, at one of three short term time windows (24, 48, or 72 h) after initiating treatment, and at first follow-up (3-5 weeks). CTC were isolated, enumerated, and expression of M30 and Bcl2 was determined using the CellSearch(®) System. RESULTS: At baseline, window, and 3-5 weeks post-treatment, 41/80 (51%), 40/80 (50%) and 21/75 (28%) patients had ≥5 CTC, respectively. At baseline, the proportion of CTC-apoptosis (M30) was inversely correlated with CTC number, and modestly inversely correlated with CTC-Bcl-2. As expected, higher CTC levels at baseline or first follow-up were associated with worse prognosis. Surprisingly, in patients with elevated CTC, higher levels of CTC-apoptosis were associated with worse prognosis, while higher CTC-Bcl-2 levels correlated with better outcomes. CONCLUSIONS: CTC apoptosis and expression of Bcl-2 can be analytically determined in patients with metastatic breast cancer and may have biological and clinical implications. Characterization of CTC for these and other markers could further increase the utility of CTC monitoring patients in clinical investigations of new anti-neoplastic agents.


Assuntos
Apoptose , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Mama/patologia , Células Neoplásicas Circulantes/patologia , Proteínas Proto-Oncogênicas c-bcl-2/análise , Antineoplásicos/uso terapêutico , Mama/efeitos dos fármacos , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Contagem de Células , Intervalo Livre de Doença , Método Duplo-Cego , Feminino , Humanos , Projetos Piloto , Prognóstico
5.
J Pain Palliat Care Pharmacother ; 25(3): 246-51, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21882978

RESUMO

In 2011, the World Health Organization (WHO) published a series of 21 guidelines to assist governments in improving their national drug control laws, regulations, and administrative procedures to promote the availability of controlled medicines for pain relief and for a variety of acute and chronic diseases and conditions. These guidelines ultimately are designed to encourage the development of policies designed to fulfill a country's dual obligation concerning these medicines: to prevent their abuse, diversion and trafficking while ensuring access for medical and scientific purposes. This article summarizes each guideline and outlines the constituents who can actively participate in making controlled medicines available to the patients who need them. It is hoped that representatives of governments and medical institutions, as well as health care professionals, will commonly and effectively use the revised WHO guidelines as a policy change tool.


Assuntos
Controle de Medicamentos e Entorpecentes/legislação & jurisprudência , Medicamentos Essenciais/provisão & distribuição , Guias como Assunto , Acessibilidade aos Serviços de Saúde/legislação & jurisprudência , Medicamentos Essenciais/efeitos adversos , Política de Saúde/legislação & jurisprudência , Humanos , Formulação de Políticas , Organização Mundial da Saúde
6.
J Clin Invest ; 120(2): 485-97, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20051626

RESUMO

Recent evidence suggests that breast cancer and other solid tumors possess a rare population of cells capable of extensive self-renewal that contribute to metastasis and treatment resistance. We report here the development of a strategy to target these breast cancer stem cells (CSCs) through blockade of the IL-8 receptor CXCR1. CXCR1 blockade using either a CXCR1-specific blocking antibody or repertaxin, a small-molecule CXCR1 inhibitor, selectively depleted the CSC population in 2 human breast cancer cell lines in vitro. Furthermore, this was followed by the induction of massive apoptosis in the bulk tumor population via FASL/FAS signaling. The effects of CXCR1 blockade on CSC viability and on FASL production were mediated by the FAK/AKT/FOXO3A pathway. In addition, repertaxin was able to specifically target the CSC population in human breast cancer xenografts, retarding tumor growth and reducing metastasis. Our data therefore suggest that CXCR1 blockade may provide a novel means of targeting and eliminating breast CSCs.


Assuntos
Neoplasias da Mama/patologia , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/transplante , Receptores de Interleucina-8A/antagonistas & inibidores , Células-Tronco/patologia , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Proteína Ligante Fas/genética , Feminino , Humanos , Camundongos , RNA Mensageiro/genética , Receptores de Interleucina-8A/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sulfonamidas/farmacologia , Transplante Heterólogo/patologia
7.
Cancer Res ; 69(4): 1302-13, 2009 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19190339

RESUMO

Tumors may be initiated and maintained by a cellular subcomponent that displays stem cell properties. We have used the expression of aldehyde dehydrogenase as assessed by the ALDEFLUOR assay to isolate and characterize cancer stem cell (CSC) populations in 33 cell lines derived from normal and malignant mammary tissue. Twenty-three of the 33 cell lines contained an ALDEFLUOR-positive population that displayed stem cell properties in vitro and in NOD/SCID xenografts. Gene expression profiling identified a 413-gene CSC profile that included genes known to play a role in stem cell function, as well as genes such as CXCR1/IL-8RA not previously known to play such a role. Recombinant interleukin-8 (IL-8) increased mammosphere formation and the ALDEFLUOR-positive population in breast cancer cell lines. Finally, we show that ALDEFLUOR-positive cells are responsible for mediating metastasis. These studies confirm the hierarchical organization of immortalized cell lines, establish techniques that can facilitate the characterization of regulatory pathways of CSCs, and identify potential stem cell markers and therapeutic targets.


Assuntos
Neoplasias da Mama/patologia , Mama/citologia , Metástase Neoplásica/patologia , Células-Tronco/patologia , Aldeído Desidrogenase/genética , Animais , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Citometria de Fluxo , Perfilação da Expressão Gênica , Homeostase , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Receptores de Interleucina-8A/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células-Tronco/citologia , Células-Tronco/fisiologia
8.
J Proteome Res ; 7(6): 2406-14, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18422355

RESUMO

Sandwich enzyme-linked immunosorbent assay (ELISA) microarrays are emerging as a strong candidate platform for multiplex biomarker analysis because of the ELISA's ability to quantitatively measure rare proteins in complex biological fluids. Advantages of this platform are high-throughput potential, assay sensitivity and stringency, and the similarity to the standard ELISA test, which facilitates assay transfer from a research setting to a clinical laboratory. However, a major concern with the multiplexing of ELISAs is maintaining high assay specificity. In this study, we systematically determine the amount of assay interference and noise contributed by individual components of a multiplexed 24-assay system. We find that nonspecific reagent cross-reactivity problems are relatively rare. We did identify the presence of contaminant antigens in a "purified antigen". We tested the validated ELISA microarray chip using paired serum samples that had been collected from four women at a 6-month interval. This analysis demonstrated that protein levels typically vary much more between individuals than within an individual over time, a result which suggests that longitudinal studies may be useful in controlling for biomarker variability across a population. Overall, this research demonstrates the importance of a stringent screening protocol and the value of optimizing the antibody and antigen concentrations when designing chips for ELISA microarrays.


Assuntos
Análise Serial de Proteínas/métodos , Proteômica/métodos , Anticorpos Monoclonais/imunologia , Antígenos/análise , Antígenos/imunologia , Antineoplásicos Hormonais/uso terapêutico , Proteínas Sanguíneas/análise , Proteínas Sanguíneas/efeitos dos fármacos , Proteínas Sanguíneas/imunologia , Neoplasias da Mama/sangue , Neoplasias da Mama/tratamento farmacológico , Reações Cruzadas/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Fator de Crescimento Epidérmico/sangue , Feminino , Humanos , Proteínas/análise , Proteínas/imunologia , Reprodutibilidade dos Testes , Tamoxifeno/uso terapêutico
9.
Cell Stem Cell ; 1(5): 555-67, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18371393

RESUMO

Application of stem cell biology to breast cancer research has been limited by the lack of simple methods for identification and isolation of normal and malignant stem cells. Utilizing in vitro and in vivo experimental systems, we show that normal and cancer human mammary epithelial cells with increased aldehyde dehydrogenase activity (ALDH) have stem/progenitor properties. These cells contain the subpopulation of normal breast epithelium with the broadest lineage differentiation potential and greatest growth capacity in a xenotransplant model. In breast carcinomas, high ALDH activity identifies the tumorigenic cell fraction, capable of self-renewal and of generating tumors that recapitulate the heterogeneity of the parental tumor. In a series of 577 breast carcinomas, expression of ALDH1 detected by immunostaining correlated with poor prognosis. These findings offer an important new tool for the study of normal and malignant breast stem cells and facilitate the clinical application of stem cell concepts.


Assuntos
Células-Tronco Adultas/enzimologia , Aldeído Desidrogenase/metabolismo , Neoplasias da Mama/enzimologia , Isoenzimas/metabolismo , Glândulas Mamárias Humanas/enzimologia , Células-Tronco Neoplásicas/enzimologia , Células-Tronco Adultas/imunologia , Família Aldeído Desidrogenase 1 , Animais , Biomarcadores/análise , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Antígeno CD24/análise , Diferenciação Celular , Linhagem da Célula , Proliferação de Células , Separação Celular , Células Cultivadas , Feminino , Citometria de Fluxo , Humanos , Receptores de Hialuronatos/análise , Imuno-Histoquímica , Glândulas Mamárias Humanas/imunologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Células-Tronco Neoplásicas/imunologia , Células-Tronco Neoplásicas/patologia , Fenótipo , Retinal Desidrogenase , Transplante de Células-Tronco , Análise de Sobrevida , Análise Serial de Tecidos , Resultado do Tratamento , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
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