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1.
Brain ; 144(6): 1711-1726, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-33693512

RESUMO

Patients with neuropathic pain often experience innocuous cooling as excruciating pain. The cell and molecular basis of this cold allodynia is little understood. We used in vivo calcium imaging of sensory ganglia to investigate how the activity of peripheral cold-sensing neurons was altered in three mouse models of neuropathic pain: oxaliplatin-induced neuropathy, partial sciatic nerve ligation, and ciguatera poisoning. In control mice, cold-sensing neurons were few in number and small in size. In neuropathic animals with cold allodynia, a set of normally silent large diameter neurons became sensitive to cooling. Many of these silent cold-sensing neurons responded to noxious mechanical stimuli and expressed the nociceptor markers Nav1.8 and CGRPα. Ablating neurons expressing Nav1.8 resulted in diminished cold allodynia. The silent cold-sensing neurons could also be activated by cooling in control mice through blockade of Kv1 voltage-gated potassium channels. Thus, silent cold-sensing neurons are unmasked in diverse neuropathic pain states and cold allodynia results from peripheral sensitization caused by altered nociceptor excitability.


Assuntos
Temperatura Baixa/efeitos adversos , Hiperalgesia/metabolismo , Neuralgia/metabolismo , Neurônios/metabolismo , Nociceptores/metabolismo , Animais , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/metabolismo , Superfamília Shaker de Canais de Potássio/metabolismo , Sensação Térmica/fisiologia
2.
Nat Methods ; 9(3): 245-53, 2012 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-22373911

RESUMO

Data-intensive research depends on tools that manage multidimensional, heterogeneous datasets. We built OME Remote Objects (OMERO), a software platform that enables access to and use of a wide range of biological data. OMERO uses a server-based middleware application to provide a unified interface for images, matrices and tables. OMERO's design and flexibility have enabled its use for light-microscopy, high-content-screening, electron-microscopy and even non-image-genotype data. OMERO is open-source software, available at http://openmicroscopy.org/.


Assuntos
Sistemas de Gerenciamento de Base de Dados , Bases de Dados Factuais , Interpretação de Imagem Assistida por Computador/métodos , Armazenamento e Recuperação da Informação/métodos , Modelos Biológicos , Software , Interface Usuário-Computador , Animais , Biologia/métodos , Simulação por Computador , Humanos
5.
Neuron ; 111(18): 2773-2774, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37734319

RESUMO

How do we know an animal is feeling pain? In this issue of Neuron, Bohic et al.1 develop computational methods to detect pain in mice, shining a light on the behavioral changes that occur during pain, its relief, and recovery.


Assuntos
Emoções , Neurônios , Animais , Camundongos , Dor
6.
bioRxiv ; 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38076807

RESUMO

The neuropeptides Substance P and CGRPα have long been thought important for pain sensation. Both peptides and their receptors are expressed at high levels in pain-responsive neurons from the periphery to the brain making them attractive therapeutic targets. However, drugs targeting these pathways individually did not relieve pain in clinical trials. Since Substance P and CGRPα are extensively co-expressed we hypothesized that their simultaneous inhibition would be required for effective analgesia. We therefore generated Tac1 and Calca double knockout (DKO) mice and assessed their behavior using a wide range of pain-relevant assays. As expected, Substance P and CGRPα peptides were undetectable throughout the nervous system of DKO mice. To our surprise, these animals displayed largely intact responses to mechanical, thermal, chemical, and visceral pain stimuli, as well as itch. Moreover, chronic inflammatory pain and neurogenic inflammation were unaffected by loss of the two peptides. Finally, neuropathic pain evoked by nerve injury or chemotherapy treatment was also preserved in peptide-deficient mice. Thus, our results demonstrate that even in combination, Substance P and CGRPα are not required for the transmission of acute and chronic pain.

7.
Biol Blood Marrow Transplant ; 18(2): 235-40, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21723225

RESUMO

Increasing numbers of allogeneic hematopoietic stem cell transplantation (allo-SCT) are being performed for patients who have failed a previous allogeneic or autologous SCT. We investigated whether the EBMT risk score could predict outcome after a subsequent allo-SCT. We analyzed prognostic factors in 124 consecutive patients who underwent a second transplantation using an allogeneic donor at our institution. Patients with either a first autologous (N = 64) or first allogeneic (N = 60) SCT were included. Age, disease stage, time interval from diagnosis to transplantation, donor type, and donor-recipient sex combination were used to establish a score from 0 to 7 points, from which 3 groups were identified. The 5-year survival probability decreased from 51.7% for risk scores 0-3 (low, n = 25), to 29.3% for risk score 4 (intermediate, n = 42), and only 10.4% for risk scores 5-7 (high, n = 57), P = .001. We propose that the EBMT risk score can identify patients most likely to benefit from a second transplantation.


Assuntos
Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas , Adolescente , Adulto , Fatores Etários , Criança , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Taxa de Sobrevida , Transplante Autólogo , Transplante Homólogo
8.
Blood ; 115(20): 4018-20, 2010 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-20304808

RESUMO

Outstanding results have been obtained in the treatment of chronic myeloid leukemia (CML) with first-line imatinib therapy. However, approximately 35% of patients will not obtain long-term benefit with this approach. Allogeneic hematopoietic stem cell transplantation (HCT) is a valuable second- and third-line therapy for appropriately selected patients. To identify useful prognostic indicators of transplantation outcome in postimatinib therapeutic interventions, we investigated the role of the HCT comorbidity index (HCT-CI) together with levels of C-reactive protein (CRP) before HCT in 271 patients who underwent myeloablative HCT for CML in first chronic phase. Multivariate analysis showed both an HCT-CI score higher than 0 and CRP levels higher than 9 mg/L independently predict inferior survival and increased nonrelapse mortality at 100 days after HCT. CML patients without comorbidities (HCT-CI score 0) with normal CRP levels (0-9 mg/L) may therefore be candidates for early allogeneic HCT after failing imatinib.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Seleção de Pacientes , Adolescente , Adulto , Proteína C-Reativa/metabolismo , Criança , Comorbidade , Feminino , Sobrevivência de Enxerto , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Taxa de Sobrevida , Condicionamento Pré-Transplante , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
9.
Blood ; 116(12): 2033-9, 2010 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-20562327

RESUMO

Natural killer (NK) cells exert antimyeloma cytotoxicity. The balance between inhibition and activation of NK-cells played by the inherited repertoire of killer immunoglobulin-like receptor (KIR) genes therefore may influence prognosis. One hundred eighty-two patients with multiple myeloma (MM) were analyzed for KIR repertoire. Multivariate analysis showed that progression-free survival (PFS) after autologous stem cell transplantation (ASCT) was significantly shorter for patients who are KIR3DS1(+) (P = .01). This was most evident for patients in complete or partial remission (good risk; GR) at ASCT. The relative risk (RR) of progression or death for patients with KIR3DS1(+) compared with KIR3DS1(-) was 1.9 (95% CI, 1.3-3.1; P = .002). The most significant difference in PFS was observed in patients with GR KIR3DS1(+) in whom HLA-Bw4, the ligand for the corresponding inhibitory receptor KIR3DL1, was missing. Patients with KIR3DS1(+) KIR3DL1(+) HLA-Bw4(-) had a significantly shorter PFS than patients who were KIR3DS1(-), translating to a difference in median PFS of 12 months (12.2 vs 24 months; P = .002). Our data show that KIR-human leukocyte antigen immunogenetics represent a novel prognostic tool for patients with myeloma, shown here in the context of ASCT, and that KIR3DS1 positivity may identify patients at greater risk of progression.


Assuntos
Antígenos HLA-B/análise , Células Matadoras Naturais/imunologia , Mieloma Múltiplo/terapia , Valor Preditivo dos Testes , Receptores KIR3DS1/análise , Transplante de Células-Tronco/mortalidade , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Antígenos HLA-B/genética , Humanos , Imunogenética , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/mortalidade , Prognóstico , Receptores KIR3DS1/genética , Transplante Autólogo
10.
Hematol Oncol ; 30(1): 8-12, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21638304

RESUMO

Immunohistochemistry can sub-classify diffuse large B-cell lymphoma (DLBCL) into germinal centre B-cell like (GCB) and non-GCB subtypes. The latter consists predominately of the activated B-cell like subgroup in which nuclear factor kappa-B activation is its characteristic. Expression of cellular caspase 8 (FLICE)-like inhibitory protein (cFLIP), a caspase 8 homologue, is regulated by nuclear factor kappa-B signalling, and it is the main inhibitor of Fas ligand activated apoptosis. To determine if cFLIP expression was confined to non-GCB subtype, we studied 66 cases of DLBCL. cFLIP expression showed no significant correlation to DLBCL subtypes (GCB or non-GCB) but was associated with a worse clinical outcome. For cFLIP positive and negative patients, the five-year event free survival was 20 and 31%, respectively (p = 0.049), and the five-year overall survival was 20 and 57%, respectively (p = 0.041).


Assuntos
Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/biossíntese , Linfoma Difuso de Grandes Células B/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/fisiologia , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/genética , Feminino , Humanos , Imuno-Histoquímica , Imunofenotipagem , Linfoma Difuso de Grandes Células B/classificação , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida
11.
PLoS One ; 17(12): e0279317, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36548287

RESUMO

Monogenic, high penetrance syndromes, conferring an increased risk of malignancies in multiple organs, are important contributors to the hereditary burden of cancer. Early detection and risk reduction strategies in patients with a cancer predisposition syndrome can save their lives. However, despite evidence supporting the benefits of early detection and risk reduction strategies, most Canadian jurisdictions have not implemented programmatic follow up of these patients. In our study site in the province of Newfoundland and Labrador (NL), Canada, there is no centralized, provincial registry of high-risk individuals. There is no continuity or coordination of care providing cancer genetics expertise and no process to ensure that patients are referred to the appropriate specialists or risk management interventions. This paper describes a study protocol to test the feasibility of obtaining and analyzing patient risk management data, specifically patients affected by hereditary breast ovarian cancer syndrome (HBOC; BRCA 1 and BRCA 2 genes) and Lynch syndrome (LS; MLH1, MSH2, MSH6, and PMS2 genes). Through a retrospective cohort study, we will describe these patients' adherence to risk management guidelines and test its relationship to health outcomes, including cancer incidence and stage. Through a qualitative interviews, we will determine the priorities and preferences of patients with any inherited cancer mutation for a follow up navigation model of risk management. Study data will inform a subsequent funding application focused on creating and evaluating a research registry and follow up nurse navigation model. It is not currently known what proportion of cancer mutation carriers are receiving care according to guidelines. Data collected in this study will provide clinical uptake and health outcome information so gaps in care can be identified. Data will also provide patient preference information to inform ongoing and planned research with cancer mutation carriers.


Assuntos
Predisposição Genética para Doença , Síndromes Neoplásicas Hereditárias , Humanos , Estudos Retrospectivos , Seguimentos , Estudos de Viabilidade , Canadá , Síndromes Neoplásicas Hereditárias/genética , Síndromes Neoplásicas Hereditárias/prevenção & controle , Sistema de Registros , Testes Genéticos/métodos
12.
Rev Bras Med Trab ; 20(1): 94-104, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36118065

RESUMO

Introduction: The pandemic caused by the severe acute respiratory syndrome coronavirus 2 imposed restrictions to movement, generating new work dynamics especially in the education sector, where remote working has become the rule. The overlapping of work-related and domestic tasks and the fear of the virus generated an additional burden to workers, with unknown effects on their quality of life. Objectives: To estimate the quality of life of employees of the education sector who were working remotely during the pandemic caused by the severe acute respiratory syndrome coronavirus 2 and identify associated factors. Methods: This is a cross-sectional study performed with a sample of 317 government employees of a federal university between August 25 2020 and September 11 2020. Standardized questionnaires concerning sociodemographic and economic aspects were constructed using the Google Forms tool. The European Health Interview Survey - Quality of Life 8-item index was used to assess quality of life. Multiple linear regression was used to check for associations between variables using quality of life scores as outcome (alpha value of 5%). This research proposal was approved by the National Research Ethics Commission, with a Certificate of Presentation for Ethical Appreciation No. 33636220.1.0000.0056. Results: The European Health Interview Survey - Quality of Life 8-item index resulted in mean adjusted scores of 3.5 ± 1.9. Quality of life was independently associated with age (ß = 0.01, 95% confidence interval 0.00 to 0.02, p = 0.015), physical activity (ß = 0.19, 95% confidence interval 0.00 to 0.38, p = 0.049), smoking habits (ß = 0.54, 95% confidence interval 0.19 to 0.88, p = 0.002), having a dedicated workspace (ß = 0.14, 95% confidence interval 0.02 to 0.26, p = 0.023), performing housework (ß =-0.20, 95% confidence interval-0.32 to-0.08, p < 0.001), financial difficulties (ß =-0.26, 95% confidence interval-0.40 to-0.12, p < 0.001), and the impact of social distancing at work (ß =-0.33, 95% confidence interval-0.47 to-0.19, p < 0.001). Conclusions: The level of quality of life within the sample was reasonable; it was higher among older participants who were physically active and did not smoke, and lower when the socioeconomic situation was unfavorable. This highlights the importance of constructing support strategies while the effects of the pandemic linger.

13.
Nat Commun ; 13(1): 6922, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376307

RESUMO

SARS-CoV-2 infection, and resulting disease, COVID-19, has a high mortality amongst patients with haematological malignancies. Global vaccine rollouts have reduced hospitalisations and deaths, but vaccine efficacy in patients with haematological malignancies is known to be reduced. The UK-strategy offered a third, mRNA-based, vaccine as an extension to the primary course in these patients. The MARCH database is a retrospective observational study of serological responses in patients with blood disorders. Here we present data on 381 patients with haematological malignancies. By comparison with healthy controls, we report suboptimal responses following two primary vaccines, with significantly enhanced responses following the third primary dose. These responses however are heterogeneous and determined by haematological malignancy sub-type and therapy. We identify a group of patients with continued suboptimal vaccine responses who may benefit from additional doses, prophylactic extended half-life neutralising monoclonal therapies (nMAB) or prompt nMAB treatment in the event of SARS-CoV-2 infection.


Assuntos
COVID-19 , Neoplasias Hematológicas , Vacinas Virais , Humanos , Vacinas contra COVID-19 , SARS-CoV-2 , COVID-19/prevenção & controle , Formação de Anticorpos , Neoplasias Hematológicas/terapia , Anticorpos Antivirais , Vacinas de mRNA
14.
Biol Blood Marrow Transplant ; 17(5): 632-9, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20708085

RESUMO

Limited data are available on immunologic responses to primary H1N1 infection in patients with hematologic malignancies. We present a prospective, case-surveillance study of such patients with real-time polymerase chain reaction (RT-PCR) confirmed H1N1-influenza who presented to our institution between September 2009 and January 2010. Ninety-two patients presented with influenza-like symptoms, and 13 had H1N1 infection confirmed by RT-PCR, including 4 allogeneic stem cell transplant recipients (1 with acute myelogenous leukemia, 1 with chronic lymphoblastic leukemia [CLL], 1 with non-Hodgkin lymphoma, and 1 with chronic myelogenous leukemia), 5 patients with multiple myeloma following autologous stem cell transplantation, 1 patient with multiple myeloma perimobilization, 2 patients with NHL post chemotherapy, and 1 patient with CLL. All 13 patients required hospitalization. Six (43%) were admitted to the intensive care unit (ICU), of whom 4 (67%) died. We evaluated B cell and T cell responses to H1N1 infection prospectively in these patients compared with those in 4 otherwise healthy controls. Within 12 weeks of diagnosis, only 6 of 11 patients developed seropositive antibody titers as measured by hemagglutination-inhibition or microneutralization assays, compared with 4 of 4 controls. H1N1-specific T cells were detected in only 2 of 8 evaluable patients compared with 4 of 4 controls. H1N1-specific T cells were functional, capable of producing interferon γ, tumor necrosis factor α, and CD107a mobilization. Furthermore, CD154 was up-regulated on CD4(+) T cells in 3 of 4 controls and 2 of 2 patients who had both B cell and T cell responses to H1N1. Post-H1N1 infection, 5 of 8 patients developed seasonal influenza-specific T cells, suggesting cross-reactivity induced by H1N1 infection. These data offer novel insights into humoral and cell-mediated immunologic responses to primary H1N1 infection.


Assuntos
Neoplasias Hematológicas/imunologia , Imunidade Celular , Imunidade Humoral , Influenza Humana/imunologia , Adulto , Idoso , Anticorpos/análise , Anticorpos/imunologia , Ligante de CD40/análise , Estudos de Casos e Controles , Feminino , Testes de Inibição da Hemaglutinação , Neoplasias Hematológicas/patologia , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/prevenção & controle , Interferon gama/análise , Interferon gama/biossíntese , Proteína 1 de Membrana Associada ao Lisossomo/análise , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante de Células-Tronco , Transplante Homólogo
15.
Haematologica ; 96(2): 307-14, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20971824

RESUMO

BACKGROUND: In 2009 the declaration by the World Health Organization of a global pandemic of influenza-H1N1 virus led to a vaccination campaign to ensure protection for immunocompromised patients. The goal of this study was to determine the efficacy of the 2009 H1N1 vaccine in patients with hematologic malignancies. DESIGN AND METHODS: We evaluated humoral and cellular immune responses to 2009 H1N1 vaccine in 97 adults with hematologic malignancies and compared these responses with those in 25 adult controls. Patients received two injections of vaccine 21 days apart and the controls received one dose. Antibody titers were measured using a hemagglutination-inhibition assay on days 0, 21 and 49 after injection of the first dose. Cellular immune responses to H1N1 were determined on days 0 and 49. RESULTS: By day 21 post-vaccination, protective antibody titers of 1:32 or more were seen in 100% of controls compared to 39% of patients with B-cell malignancies (P<0.001), 46% of allogeneic stem cell transplant recipients (P<0.001) and 85% of patients with chronic myeloid leukemia (P=0.086). After a second dose, seroprotection rates increased to 68%, (P=0.008), 73%, (P=0.031), and 95% (P=0.5) in patients with B-cell malignancies, after allogeneic stem cell transplantation and with chronic myeloid leukemia, respectively. On the other hand, T-cell responses to H1N1 vaccine were not significantly different between patients and controls. CONCLUSIONS: These data demonstrate the efficacy of H1N1 vaccine in most patients with hematologic malignancies and support the recommendation for the administration of two doses of vaccine in immunocompromised patients. These results may contribute towards the development of evidence-based guidelines for influenza vaccination in such patients in the future.


Assuntos
Neoplasias Hematológicas/virologia , Hospedeiro Imunocomprometido , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/uso terapêutico , Influenza Humana/imunologia , Vacinação/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Estudos de Casos e Controles , Feminino , Testes de Inibição da Hemaglutinação , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/terapia , Humanos , Imunidade Celular , Influenza Humana/complicações , Influenza Humana/prevenção & controle , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Transplante de Células-Tronco , Taxa de Sobrevida , Adulto Jovem
16.
Hematol Oncol ; 29(2): 75-80, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20635327

RESUMO

High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) is a recognized treatment option for patients with relapsed diffuse large B-cell lymphoma. We have analysed 51 patients who underwent ASCT after LACE (lomustine (CCNU), cytarabine (Ara-C), cyclophosphamide, etoposide) conditioning for relapsed (n = 34, 67%) or primary refractory (n = 17, 33%) diffuse large B-cell lymphoma. With a median follow-up of 60 months (range 2-216) the probabilities of overall survival (OS) and progression-free survival (PFS) at 5 years were 47 and 42%, respectively. The cumulative treatment-related mortality was 10% (n = 5). Probabilities for OS and PFS at 5 years were 56 and 50% for patients with chemosensitive and 29 and 27% for patients with chemorefractory disease. In multivariate analysis abnormal pre-ASCT levels of C-reactive protein (>5 mg/L) were identified as a risk factor for worse OS, whereas abnormal pre-ASCT levels of C-reactive protein and chemoresistance predicted inferior PFS. LACE followed by ASCT is an effective treatment for approximately half of patients with chemosensitive relapsed diffuse large B-cell lymphoma, and a proportion of chemorefractory patients also benefit.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/métodos , Linfoma Difuso de Grandes Células B/terapia , Condicionamento Pré-Transplante/métodos , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Terapia Combinada , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Citarabina/administração & dosagem , Citarabina/efeitos adversos , Diarreia/etiologia , Resistencia a Medicamentos Antineoplásicos , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Lomustina/administração & dosagem , Lomustina/efeitos adversos , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Recidiva , Estomatite/etiologia , Análise de Sobrevida , Transplante Autólogo , Resultado do Tratamento , Vômito/etiologia , Adulto Jovem
17.
Arch Environ Contam Toxicol ; 61(1): 14-28, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21442249

RESUMO

Three sets of effects-based sediment-quality guidelines (SQGs) were evaluated to support the selection of sediment-quality benchmarks for assessing risks to benthic invertebrates in the Calcasieu Estuary, Louisiana. These SQGs included probable effect concentrations (PECs), effects range median values (ERMs), and logistic regression model (LRMs)-based T50 values. The results of this investigation indicate that all three sets of SQGs tend to underestimate sediment toxicity in the Calcasieu Estuary (i.e., relative to the national data sets), as evaluated using the results of 10-day toxicity tests with the amphipod, Hyalella azteca, or Ampelisca abdita, and 28-day whole-sediment toxicity tests with the H. azteca. These results emphasize the importance of deriving site-specific toxicity thresholds for assessing risks to benthic invertebrates.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Sedimentos Geológicos/química , Invertebrados/efeitos dos fármacos , Rios/química , Poluentes Químicos da Água/toxicidade , Animais , Ecossistema , Monitoramento Ambiental , Modelos Logísticos , Louisiana , Medição de Risco , Testes de Toxicidade , Poluentes Químicos da Água/análise
18.
Arch Environ Contam Toxicol ; 61(1): 1-13, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21442250

RESUMO

A remedial investigation/feasibility study (RI/FS) of the Calcasieu Estuary cooperative site was initiated in 1998. This site, which is located in the southwestern portion of Louisiana in the vicinity of Lake Charles, includes the portion of the estuary from the saltwater barrier on the Calcasieu River to Moss Lake. As part of the RI/FS, a baseline ecological risk assessment (BERA) was conducted to assess the risks to aquatic organisms and aquatic-dependent wildlife exposed to environmental contaminants. The purpose of the BERA was to determine if adverse effects on ecological receptors are occurring in the estuary; to evaluate the nature, severity, and areal extent of any such effects; and to identify the substances that are causing or substantially contributing to effects on ecological receptors. This article describes the environmental setting and site history, identifies the chemicals of potential concern, presents the exposure scenarios and conceptual model for the site, and summarizes the assessment and measurement endpoints that were used in the investigation. Two additional articles in this series describe the results of an evaluation of effects-based sediment-quality guidelines as well as an assessment of risks to benthic invertebrates associated with exposure to contaminated sediment.


Assuntos
Organismos Aquáticos , Invertebrados , Modelos Biológicos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Animais , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos/química , Louisiana , Projetos de Pesquisa , Medição de Risco , Poluentes Químicos da Água/química
19.
Arch Environ Contam Toxicol ; 61(1): 29-58, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21442248

RESUMO

The sediments in the Calcasieu Estuary are contaminated with a wide variety of chemicals of potential concern (COPCs), including heavy metals, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, phthalates, chlorinated benzenes, and polychlorinated dibenzo-p-dioxins and dibenzofurans. The sources of these COPCs include both point and non-point source discharges. As part of a baseline ecological risk assessment, the risks to benthic invertebrates posed by exposure to sediment-associated COPCs were assessed using five lines of evidence, including whole-sediment chemistry, pore-water chemistry, whole-sediment toxicity, pore-water toxicity, and benthic invertebrate community structure. The results of this assessment indicated that exposure to whole sediments and/or pore water from the Calcasieu Estuary generally posed low risks to benthic invertebrate communities (i.e., risks were classified as low for 68% of the sampling locations investigated). However, incremental risks to benthic invertebrates (i.e., compared with those associated with exposure to conditions in reference areas) were indicated for 32% of the sampling locations within the estuary. Of the three areas of concern (AOCs) investigated, the risks to benthic invertebrates were highest in the Bayou d'Inde AOC; risks were generally lower in the Upper Calcasieu River AOC and Middle Calcasieu River AOC. The areas showing the highest risks to sediment-dwelling organisms were generally located in the vicinity of point source discharges of COPCs. These results provided risk managers with the information required to make decisions regarding the need for remedial actions at the site.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Sedimentos Geológicos/química , Invertebrados/efeitos dos fármacos , Rios/química , Poluentes Químicos da Água/toxicidade , Animais , Biota , Ecossistema , Monitoramento Ambiental , Louisiana , Medição de Risco , Testes de Toxicidade , Poluentes Químicos da Água/análise
20.
Neuron ; 109(9): 1497-1512.e6, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33823138

RESUMO

Deletion of SCN9A encoding the voltage-gated sodium channel NaV1.7 in humans leads to profound pain insensitivity and anosmia. Conditional deletion of NaV1.7 in sensory neurons of mice also abolishes pain, suggesting that the locus of analgesia is the nociceptor. Here we demonstrate, using in vivo calcium imaging and extracellular recording, that NaV1.7 knockout mice have essentially normal nociceptor activity. However, synaptic transmission from nociceptor central terminals in the spinal cord is greatly reduced by an opioid-dependent mechanism. Analgesia is also reversed substantially by central but not peripheral application of opioid antagonists. In contrast, the lack of neurotransmitter release from olfactory sensory neurons is opioid independent. Male and female humans with NaV1.7-null mutations show naloxone-reversible analgesia. Thus, inhibition of neurotransmitter release is the principal mechanism of anosmia and analgesia in mouse and human Nav1.7-null mutants.


Assuntos
Analgesia , Canal de Sódio Disparado por Voltagem NAV1.7/deficiência , Neurônios Receptores Olfatórios/metabolismo , Dor/genética , Transmissão Sináptica/fisiologia , Adulto , Animais , Feminino , Humanos , Masculino , Camundongos , Canal de Sódio Disparado por Voltagem NAV1.7/genética , Transtornos do Olfato/congênito , Transtornos do Olfato/genética
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