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1.
Chem Commun (Camb) ; 60(32): 4302-4305, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38530770

RESUMO

A dynamic covalent approach was exploited to generate a family of homometallic [PtnL2n]2n+ cage (predominantly [Pt2L4]4+ systems) architectures. The family of platinum(II) architectures were characterized using 1H nuclear magnetic resonance (NMR) and diffusion ordered spectroscopy (DOSY), electrospray ionization mass spectrometry (ESI-MS) and the molecular structures of two cages were determined by X-ray crystallography.

2.
Disaster Med Public Health Prep ; 16(5): 1753-1760, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-33762057

RESUMO

The ongoing pandemic disaster of coronavirus erupted with the first confirmed cases in Wuhan, China, in December 2019, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) novel coronavirus, the disease referred to as coronavirus disease 2019, or COVID-19. The World Health Organization (WHO) confirmed the outbreak and determined it a global pandemic. The current pandemic has infected nearly 300 million people and killed over 3 million. The current COVID-19 pandemic is smashing every public health barrier, guardrail, and safety measure in underdeveloped and the most developed countries alike, with peaks and troughs across time. Greatly impacted are those regions experiencing conflict and war. Morbidity and mortality increase logarithmically for those communities at risk and that lack the ability to promote basic preventative measures. States around the globe struggle to unify responses, make gains on preparedness levels, identify and symptomatically treat positive cases, and labs across the globe frantically rollout various vaccines and effective surveillance and therapeutic mechanisms. The incidence and prevalence of COVID-19 may continue to increase globally as no unified disaster response is manifested and disinformation spreads. During this failure in response, virus variants are erupting at a dizzying pace. Ungoverned spaces where nonstate actors predominate and active war zones may become the next epicenter for COVID-19 fatality rates. As the incidence rates continue to rise, hospitals in North America and Europe exceed surge capacity, and immunity post infection struggles to be adequately described. The global threat in previously high-quality, robust infrastructure health-care systems in the most developed economies are failing the challenge posed by COVID-19; how will less-developed economies and those health-care infrastructures that are destroyed by war and conflict fare until adequate vaccine penetrance in these communities or adequate treatment are established? Ukraine and other states in the Black Sea Region are under threat and are exposed to armed Russian aggression against territorial sovereignty daily. Ukraine, where Russia has been waging war since 2014, faces this specific dual threat: disaster response to violence and a deadly infectious disease. To best serve biosurveillance, aid in pandemic disaster response, and bolster health security in Europe, across the North Atlantic Treaty Alliance (NATO) and Black Sea regions, increased NATO integration, across Ukraine's disaster response structures within the Ministries of Health, Defense, and Interior must be reinforced and expanded to mitigate the COVID-19 disaster.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias/prevenção & controle , SARS-CoV-2 , Ucrânia , RNA Viral
4.
EBioMedicine ; 37: 205-213, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30385234

RESUMO

BACKGROUND: Using patient-derived xenografts (PDXs) to assess chemosensitivity to anti-cancer agents in real-time may improve cancer care by enabling individualized clinical decision-making. However, it is unknown whether this new approach will be met with acceptance by patients, family and community. METHODS: We used a cross-sectional structured survey to investigate PDX acceptability with 1550 individuals across Australia and New Zealand (648 survivors of adult and childhood cancer, versus 650 community comparisons; and 48 parents of childhood cancer survivors versus 204 community parents). We identified factors influencing willingness-to-use PDXs, willingness-to-pay, maximum acceptable wait-time, and maximum acceptable number of mice used per patient. FINDINGS: PDXs were highly acceptable: >80% of those affected by cancer felt the potential advantages of PDXs outweighed the disadvantages (community participants: 68%). Survivors' and survivors' parents' most highly endorsed advantage was 'increased chance of survival'. 'Harm to animals' was the least endorsed disadvantage for all groups. Cancer survivors were more willing to use PDXs than community comparisons [p < ·001]. Survivors and survivors' parents were willing to pay more [p < ·001; p = ∙004 respectively], wait longer for results [p = ·03; p = ∙01], and use more mice [p = ·01; p < ∙001] than community comparisons. Male survivors found PDXs more acceptable [p = ·01] and were willing to pay more [p < ·001] than female survivors. Survivors with higher incomes found PDXs more acceptable [p = ·002] and were willing to pay more [p < ·001] than survivors with lower incomes. Mothers found PDXs more acceptable [p = ·04] but were less willing to wait [p = ·02] than fathers. INTERPRETATION: We found significant attitudinal support for PDX-guided cancer care. Willingness-to-pay and maximum acceptable number of mice align well with likely future usage. Maximum acceptable wait-times were lower than is currently achievable, highlighting an important area for future patient education until technology has caught up.


Assuntos
Sobreviventes de Câncer , Aceitação pelo Paciente de Cuidados de Saúde , Medicina de Precisão/métodos , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto , Animais , Feminino , Humanos , Masculino , Camundongos , Projetos Piloto , Fatores Sexuais
5.
Global Health ; 14(1): 27, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29510752

RESUMO

This short letter from the field is offered as a rapid communiqué of the emergency medical situation in Mosul and surrounding areas on the eve of the final onslaught to liberate the city. This letter is based on emergency medical work at two World Health Organization (WHO) and Ministry of Health (MoH) Iraq lead Role II+ Field Hospital facilities south of Mosul City from April to June 2017; these facilities are currently and temporarily managed and administered by private medical industry until full handover to MoH Iraq, with WHO support and expert facilitation. The prominence of non-state actors in the conflict, using hybrid warfare tactics that maximize casualties, makes health security a particular challenge for the global community. This challenge requires health leaders and other actors in the region to set clear strategic goals that support public health of the many millions displaced, maimed and affected by the war. Whether in clinical medicine, development, peace and stability operations, or global health diplomacy, the shared values and conviction to best serve vulnerable communities and mitigate morbidity must embrace the lessons of evidenced based practice derived from military medical experience. WHO is leading the charge in disaster response for the conflict in Iraq, and many challenges remain. This might also include developing a new process in emergency medical response that utilizes private contracting to improve efficiency in delivery and overall sustainability.


Assuntos
Serviços Médicos de Emergência/organização & administração , Unidades Móveis de Saúde , Guerra , Humanos , Iraque , Organização Mundial da Saúde
6.
Dalton Trans ; 47(4): 997-1002, 2018 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-29271436

RESUMO

Ligands containing the bidentate 2-pyridyl-1,2,3-triazole and tridentate 2,6-pyridyl-bis(1,2,3-triazole) moieties have emerged as alternatives to 2,2'-bypridine and 2,2':6',2''-terpyridine and other nitrogen-containing bi- and tri-dentate chelators. Because these "click" ligands are readily functionalised they are attractive options for the development of functional coordination complexes. This Frontiers Article discusses key recent reports on functional CuAAC "click" complexes in the areas of biological agency, photophysics, and catalysis.

7.
Clin Genet ; 92(6): 569-578, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28170090

RESUMO

This review assessed parents' attitudes toward childhood genetic testing for health conditions, with a focus on perceived advantages and disadvantages. We also evaluated the factors that influence parents' attitudes toward childhood genetic testing. We searched Medline, Medline In-Process, EMBASE, PsycINFO, Social Work Abstracts and CINAHL. We screened 945 abstracts and identified 21 studies representing the views of 3934 parents. Parents reported largely positive attitudes toward childhood genetic testing across different genetic tests with varying medical utility. Parents perceived a range of advantages and disadvantages of childhood genetic testing. Childhood genetic testing was viewed by most as beneficial. Parents' education level, genetic status, sex and sociodemographic status were associated with reported attitudes. This yielded some conflicting findings, indicating the need for further research. Genetic counseling remains essential to support this population in making well-informed decisions. Targeted interventions tailored to specific families with different sociodemographic characteristics may be useful. Further research on the long-term impact of childhood genetic testing on families is warranted.


Assuntos
Aconselhamento Genético/psicologia , Doenças Genéticas Inatas/psicologia , Testes Genéticos , Conhecimentos, Atitudes e Prática em Saúde , Pais/psicologia , Adulto , Austrália , Criança , Tomada de Decisão Clínica , Feminino , Doenças Genéticas Inatas/diagnóstico , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Fatores Socioeconômicos
8.
Ann Behav Med ; 51(3): 432-441, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28054312

RESUMO

BACKGROUND: Nocebo nausea is a debilitating and prevalent side effect that can develop after conditioning occurs between cues present in the treatment context and the experience of nausea. Interventions that retard conditioning may therefore be able to reduce nocebo nausea. PURPOSE: To test whether 'latent inhibition', where pre-exposing cues in the absence of an outcome retards subsequent learning about those cues, could reduce nocebo nausea in healthy adults. METHODS: We examined this possibility using a Galvanic Vestibular Stimulation (GVS) model of nausea in healthy participants, with pre-exposure to the treatment cues achieved using a placebo version of GVS. RESULTS: In Experiment 1 we found clear evidence of conditioned nocebo nausea that was eradicated by latent inhibition following pre-exposure to placebo stimulation. Experiment 2 tested whether deception, which may be unethical in clinical settings, was necessary to produce latent inhibition by including an open pre-exposure group informed they were pre-exposed to placebo stimulation. Experiment 2 replicated the latent inhibition effect on nocebo nausea following deceptive pre-exposure from Experiment 1 and found that open pre-exposure was just as effective for reducing nocebo nausea. In both experiments, there was an interesting discrepancy found in expectancy ratings whereby expectations appeared to drive the development of conditioned nocebo nausea, but were not responsible for its suppression through latent inhibition. CONCLUSIONS: These findings have significant clinical implications. Applying open pre-exposure in clinical settings may effectively and ethically reduce the development of nocebo effects for nausea and other conditions via latent inhibition.


Assuntos
Condicionamento Psicológico/fisiologia , Náusea/psicologia , Efeito Nocebo , Adolescente , Adulto , Sinais (Psicologia) , Enganação , Feminino , Humanos , Masculino , Adulto Jovem
9.
Eur J Hum Genet ; 24(11): 1517-1523, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27329735

RESUMO

Selection of women for treatment-focused genetic testing (TFGT) following a new diagnosis of breast cancer is changing. Increasingly a patient's age and tumour characteristics rather than only their family history are driving access to TFGT, but little is known about the impact of receiving carrier-positive results in individuals with no family history of cancer. This study assesses the role of knowledge of a family history of cancer on psychosocial adjustment to TFGT in both women with and without mutation carrier-positive results. In-depth semistructured interviews were conducted with 20 women who had undergone TFGT, and who had been purposively sampled to represent women both family history and carrier status, and subjected to a rigorous qualitative analysis. It was found that mutation carriers without a family history reported difficulties in making surgical decisions quickly, while in carriers with a family history, a decision regarding surgery, electing for bilateral mastectomy (BM), had often already been made before receipt of their result. Long-term adjustment to a mutation-positive result was hindered by a sense of isolation not only by those without a family history but also those with a family history who lacked an affected relative with whom they could identify. Women with a family history who had no mutation identified and who had not elected BM reported a lack of closure following TFGT. These findings indicate support deficits hindering adjustment to positive TFGT results for women with and without a family history, particularly in regard to immediate decision-making about risk-reducing surgery.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/psicologia , Testes Genéticos , Mutação , Revelação da Verdade , Adulto , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Heterozigoto , Humanos , Pessoa de Meia-Idade , Inquéritos e Questionários
10.
J Psychosom Res ; 78(5): 484-488, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25687878

RESUMO

OBJECTIVE: Traditional rotation-based models of placebo nausea are limited because they do not have vehicle settings and are tied to their context. The present study introduces a new model for examining placebo-induced nausea in the laboratory that overcomes these limitations, namely, Galvanic Vestibular Stimulation (GVS). GVS stimulates the vestibular system to cause nausea through sensory mismatch with visual cues and importantly has a non-nauseating placebo setting. Using this, we tested whether conditioning could elicit placebo nausea when participants were later exposed to placebo stimulation as well as whether this placebo nausea was generalised across contexts--something that is extremely difficult to test with rotation-based models of placebo nausea. METHODS: Thirty healthy undergraduate students were randomised to receive either placebo GVS (controls) or active GVS during training (Context-Consistent and Context-Change). On test, all groups received placebo GVS. The controls and Context-Consistent groups were tested in the same context as training, whereas the Context-Change group was tested in a new context. RESULTS: Participants conditioned with nausea during training had significantly higher nausea symptom ratings after placebo stimulation on test than those given no conditioning. This placebo-induced nausea also generalised to a novel test context with no differences observed between the Context-Change and Context-Consistent groups. CONCLUSION: GVS provides a new model of placebo-induced nausea that overcomes limitations to traditional rotation-based paradigms. Future studies should use this device to explore the effect of instructions and conditioning on the development of placebo nausea and to assess the efficacy of conditioning-based interventions for clinical use.


Assuntos
Estimulação Elétrica , Náusea/etiologia , Efeito Placebo , Vestíbulo do Labirinto , Adulto , Feminino , Humanos , Masculino
11.
Nat Neurosci ; 16(8): 1111-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23792945

RESUMO

Relapse to alcohol abuse is an important clinical issue that is frequently caused by cue-induced drug craving. Therefore, disruption of the memory for the cue-alcohol association is expected to prevent relapse. It is increasingly accepted that memories become labile and erasable soon after their reactivation through retrieval during a memory reconsolidation process that depends on protein synthesis. Here we show that reconsolidation of alcohol-related memories triggered by the sensory properties of alcohol itself (odor and taste) activates mammalian target of rapamycin complex 1 (mTORC1) in select amygdalar and cortical regions in rats, resulting in increased levels of several synaptic proteins. Furthermore, systemic or central amygdalar inhibition of mTORC1 during reconsolidation disrupts alcohol-associated memories, leading to a long-lasting suppression of relapse. Our findings provide evidence that the mTORC1 pathway and its downstream substrates are crucial in alcohol-related memory reconsolidation and highlight this pathway as a therapeutic target to prevent relapse.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Anisomicina/farmacologia , Consumo Excessivo de Bebidas Alcoólicas/psicologia , Memória/efeitos dos fármacos , Complexos Multiproteicos/antagonistas & inibidores , Córtex Pré-Frontal/fisiopatologia , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Tonsila do Cerebelo/efeitos dos fármacos , Animais , Anisomicina/uso terapêutico , Consumo Excessivo de Bebidas Alcoólicas/prevenção & controle , Condicionamento Operante/fisiologia , Sinais (Psicologia) , Etanol/sangue , Etanol/química , Etanol/farmacologia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Memória/fisiologia , Complexos Multiproteicos/fisiologia , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Plasticidade Neuronal , Odorantes , Fosforilação/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , Biossíntese de Proteínas/fisiologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Ratos , Ratos Long-Evans , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Sirolimo/uso terapêutico , Comportamento Espacial/efeitos dos fármacos , Comportamento Espacial/fisiologia , Serina-Treonina Quinases TOR/fisiologia , Paladar
12.
J Neurosci ; 31(27): 9885-94, 2011 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-21734280

RESUMO

We previously showed that infusion of glial cell line-derived neurotrophic factor (GDNF) into the ventral tegmental area (VTA) rapidly reduces alcohol intake and relapse (Carnicella et al., 2008, 2009a), and increases dopamine (DA) levels in the nucleus accumbens (NAc) of alcohol-naive rats (Wang et al., 2010). Withdrawal from excessive alcohol intake is associated with a reduction in NAc DA levels, whereas drug-induced increases in NAc DA levels are associated with reward. We therefore tested whether GDNF in the VTA reverses alcohol withdrawal-associated DA deficiency and/or possesses rewarding properties. Rats were trained for 7 weeks to consume high levels of alcohol (5.47 ± 0.37 g/kg/24 h) in intermittent access to 20% alcohol in a two-bottle choice procedure. Using in vivo microdialysis, we show that 24 h withdrawal from alcohol causes a substantial reduction in NAc DA overflow, which was reversed by intra-VTA GDNF infusion. Using conditioned place preference (CPP) paradigm, we observed that GDNF on its own does not induce CPP, suggesting that the growth factor is not rewarding. However, GDNF blocked acquisition and expression of alcohol-CPP. In addition, GDNF induced a downward shift in the dose-response curve for operant self-administration of alcohol, further suggesting that GDNF suppresses, rather than substitutes for, the reinforcing effects of alcohol. Our findings suggest that GDNF reduces alcohol-drinking behaviors by reversing an alcohol-induced allostatic DA deficiency in the mesolimbic system. In addition, as it lacks abuse liability, the study further highlights GDNF as a promising target for treatment of alcohol use/abuse disorders.


Assuntos
Álcoois/farmacologia , Alostase/efeitos dos fármacos , Dopamina/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/farmacologia , Sistema Límbico/efeitos dos fármacos , Recompensa , Consumo de Bebidas Alcoólicas/psicologia , Álcoois/metabolismo , Animais , Comportamento de Escolha/efeitos dos fármacos , Condicionamento Operante/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sistema Límbico/metabolismo , Masculino , Microdiálise/métodos , Modelos Biológicos , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Long-Evans , Autoadministração , Estatísticas não Paramétricas
13.
Biol Psychiatry ; 70(6): 575-82, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21549353

RESUMO

BACKGROUND: Neuroadaptations within the nucleus accumbens (NAc) have been implicated in molecular mechanisms underlying the development and/or maintenance of alcohol abuse disorders. We recently reported that the activation of mammalian target of rapamycin complex 1 (mTORC1) signaling pathway in the NAc of rodents, after exposure to alcohol, contributes to alcohol drinking behaviors. The kinase AKT is a main upstream activator of the mTORC1 pathway. We therefore hypothesized that the activation of AKT in the NAc in response to alcohol exposure plays an important role in mechanisms that underlie excessive alcohol consumption. METHODS: Western blot analysis was used to assess the phosphorylation levels of enzymes. Acute exposure of mice to alcohol was achieved by the administration of 2 g/kg alcohol intraperitoneally (i.p.). Two-bottle choice and operant self-administration procedures were used to assess drinking behaviors in rats. RESULTS: We found that acute systemic administration of alcohol and recurring cycles of excessive voluntary consumption of alcohol and withdrawal result in the activation of AKT signaling in the NAc of rodents. We show that inhibition of AKT or its upstream activator, phosphatidylinositol-3-kinase (PI3K), within the NAc of rats attenuates binge drinking as well as alcohol but not sucrose operant self-administration. CONCLUSIONS: Our results suggest that the activation of the AKT pathway in the NAc in response to alcohol exposure is an important contributor to the molecular mechanisms underlying alcohol-drinking behaviors. AKT signaling pathway inhibitors are therefore potential candidates for drug development for the treatment of alcohol use and abuse disorders.


Assuntos
Consumo de Bebidas Alcoólicas/metabolismo , Comportamento Aditivo/metabolismo , Comportamento Aditivo/fisiopatologia , Condicionamento Operante/efeitos dos fármacos , Núcleo Accumbens/fisiopatologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Transdução de Sinais/fisiologia , Consumo de Bebidas Alcoólicas/fisiopatologia , Androstadienos/administração & dosagem , Androstadienos/farmacologia , Animais , Comportamento de Escolha/efeitos dos fármacos , Comportamento de Escolha/fisiologia , Condicionamento Operante/fisiologia , Etanol/administração & dosagem , Etanol/antagonistas & inibidores , Etanol/intoxicação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microinjeções , Núcleo Accumbens/metabolismo , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Long-Evans , Ribonucleosídeos/administração & dosagem , Ribonucleosídeos/farmacologia , Autoadministração/métodos , Autoadministração/psicologia , Transdução de Sinais/efeitos dos fármacos , Sacarose/administração & dosagem , Wortmanina
14.
J Neurosci ; 31(6): 2180-7, 2011 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-21307254

RESUMO

We report here that the Src family tyrosine kinase Lyn negatively regulates the release of dopamine (DA) in the mesolimbic system, as well as the rewarding properties of alcohol. Specifically, we show that RNA interference-mediated knockdown of Lyn expression results in an increase in KCl-induced DA release in DAergic-like SH-SY5Y cells, whereas overexpression of a constitutively active form of Lyn (CA-Lyn) leads to a decrease of DA release. Activation of ventral tegmental area (VTA) DAergic neurons results in DA overflow in the nucleus accumbens (NAc), and we found that the evoked release of DA was higher in the NAc of Lyn knock-out (Lyn KO) mice compared with wild-type littermate (Lyn WT) controls. Acute exposure of rodents to alcohol causes a rapid increase in DA release in the NAc, and we show that overexpression of CA-Lyn in the VTA of mice blocked alcohol-induced (2 g/kg) DA release in the NAc. Increase in DA levels in the NAc is closely associated with reward-related behaviors, and overexpression of CA-Lyn in the VTA of mice led to an attenuation of alcohol reward, measured in a conditioned place preference paradigm. Conversely, alcohol place preference was increased in Lyn KO mice compared with Lyn WT controls. Together, our results suggest a novel role for Lyn kinase in the regulation of DA release in the mesolimbic system, which leads to the control of alcohol reward.


Assuntos
Condicionamento Operante/fisiologia , Dopamina/metabolismo , Regulação da Expressão Gênica/fisiologia , Núcleo Accumbens/metabolismo , Área Tegmentar Ventral/metabolismo , Quinases da Família src/metabolismo , Animais , Comportamento Animal , Linhagem Celular , Depressores do Sistema Nervoso Central/farmacologia , Condicionamento Operante/efeitos dos fármacos , Eletroquímica/métodos , Inibidores Enzimáticos/farmacologia , Etanol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Proteínas de Fluorescência Verde/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microdiálise , Núcleo Accumbens/efeitos dos fármacos , Cloreto de Potássio/farmacologia , Pirimidinas/farmacologia , Interferência de RNA/fisiologia , Estatísticas não Paramétricas , Transfecção/métodos , Trítio/metabolismo , Área Tegmentar Ventral/efeitos dos fármacos , Quinases da Família src/deficiência , Quinases da Família src/genética
15.
Alcohol Clin Exp Res ; 35(1): 116-25, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21039633

RESUMO

BACKGROUND: Oral ethanol self-administration procedures in rats are useful preclinical tools for the evaluation of potential new pharmacotherapies as well as for the investigation into the etiology of alcohol abuse disorders and addiction. Determination of the effects of a potential treatment on a full ethanol dose-response curve should be essential to predict its clinical efficacy. Unfortunately, this approach has not been fully explored because of the aversive taste reaction to moderate to high doses of ethanol, which may interfere with consumption. In this study, we set out to determine whether a meaningful dose-response curve for oral ethanol self-administration can be obtained in rats. METHODS: Long-Evans rats were trained to self-administer a 20% ethanol solution in an operant procedure following a history of excessive voluntary ethanol intake. After stabilization of ethanol self-administration, the concentration of the solution was varied from 2.5 to 60% (v/v), and operant and drinking behaviors, as well as blood ethanol concentration (BEC), were evaluated following the self-administration of a 20, 40, and 60% ethanol solution. RESULTS: Varying the concentration of ethanol from 2.5 to 60% after the development of excessive ethanol consumption led to a typical inverted U-shaped dose-response curve. Importantly, rats adapted their level and pattern of responding to changes in ethanol concentration to obtain a constant level of intake and BEC, suggesting that their operant behavior is mainly driven by the motivation to obtain a specific pharmacological effect of ethanol. CONCLUSION: This procedure can be a useful and straightforward tool for the evaluation of the effects of new potential pharmacotherapies for the treatment of alcohol abuse disorders.


Assuntos
Consumo de Bebidas Alcoólicas , Alcoolismo , Depressores do Sistema Nervoso Central/administração & dosagem , Condicionamento Operante , Etanol/administração & dosagem , Animais , Relação Dose-Resposta a Droga , Etanol/sangue , Masculino , Ratos , Ratos Long-Evans , Autoadministração , Paladar
16.
Addict Biol ; 15(4): 424-33, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21040239

RESUMO

Ibogaine is a naturally occurring alkaloid that has been reported to decrease various adverse phenotypes associated with exposure to drugs of abuse and alcohol in human and rodent models. Unfortunately, ibogaine cannot be used as a medication to treat addiction because of severe side effects. Previously, we reported that the desirable actions of ibogaine to reduce self-administration of, and relapse to, alcohol consumption are mediated via the upregulation of the expression of the glial cell line-derived neurotrophic factor (GDNF) in the midbrain ventral tegmental area (VTA), and the consequent activation of the GDNF pathway. The ibogaine metabolite, noribogaine, and a synthetic derivative of ibogaine, 18-Methoxycoronaridine (18-MC), possess a similar anti-addictive profile as ibogaine in rodent models, but without some of its adverse side effects. Here, we determined whether noribogaine and/or 18-MC, like ibogaine, increase GDNF expression, and whether their site of action to reduce alcohol consumption is the VTA. We used SH-SY5Y cells as a cell culture model and found that noribogaine, like ibogaine, but not 18-MC, induces a robust increase in GDNF mRNA levels. Next, we tested the effect of intra-VTA infusion of noribogaine and 18-MC on rat operant alcohol self-administration and found that noribogaine, but not 18-MC, in the VTA decreases responding for alcohol. Together, our results suggest that noribogaine and 18-MC have different mechanisms and sites of action.


Assuntos
Dissuasores de Álcool/farmacologia , Consumo de Bebidas Alcoólicas/genética , Alcoolismo/genética , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Ibogaína/análogos & derivados , Ibogaína/farmacologia , Área Tegmentar Ventral/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Condicionamento Operante/efeitos dos fármacos , Humanos , Masculino , Motivação/efeitos dos fármacos , RNA Mensageiro/genética , Ratos , Ratos Long-Evans , Autoadministração
17.
J Neurosci ; 30(30): 10187-98, 2010 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-20668202

RESUMO

A growing number of studies suggest that the development of compulsive drug seeking and taking depends on dorsostriatal mechanisms. We previously observed that ex vivo acute exposure of the dorsal striatum to, and withdrawal from, alcohol induces long-term facilitation (LTF) of the activity of NR2B-containing NMDA receptors (NR2B-NMDARs) in a mechanism that requires the Src family protein tyrosine kinase (PTK), Fyn (Wang et al., 2007). In the present study, we first compared alcohol's actions in rat dorsomedial (DMS) and the dorsolateral (DLS) subregions of the striatum, which differ in their anatomical connectivity and function. We found that alcohol-mediated induction of LTF of NR2B-NMDAR activity is centered in the DMS. Next, we tested whether in vivo exposure of rats to alcohol leads to long-term adaptations of the NMDAR system in the DMS. We observed that repeated daily administration of alcohol results in a long-lasting increase in the activity of the NR2B-NMDARs in the DMS. The same procedure leads to a prolonged activation of Fyn, increased NR2B phosphorylation, and membrane localization of the subunit. Importantly, similar electrophysiological and biochemical modifications were observed in the DMS of rats that consumed large quantities of alcohol. Finally, we show that inhibition of NR2B-NMDARs or Src family PTKs in the DMS, but not in the DLS, significantly decreases operant self-administration of alcohol and reduces alcohol-priming-induced reinstatement of alcohol seeking. Our results suggest that the upregulation of NR2B-NMDAR activity within the DMS by alcohol contributes to the maladaptive synaptic changes that lead to excessive alcohol intake and relapse.


Assuntos
Adaptação Fisiológica , Consumo de Bebidas Alcoólicas/patologia , Corpo Estriado/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/metabolismo , Consumo de Bebidas Alcoólicas/sangue , Consumo de Bebidas Alcoólicas/psicologia , Análise de Variância , Animais , Comportamento Animal , Depressores do Sistema Nervoso Central/administração & dosagem , Depressores do Sistema Nervoso Central/efeitos adversos , Depressores do Sistema Nervoso Central/sangue , Comportamento de Escolha , Condicionamento Operante/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/patologia , Etanol/administração & dosagem , Etanol/efeitos adversos , Etanol/sangue , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Imunoprecipitação/métodos , Técnicas In Vitro , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Técnicas de Patch-Clamp , Fenóis/farmacologia , Fosforilação/efeitos dos fármacos , Piperidinas/farmacologia , Proteínas Proto-Oncogênicas c-fyn/metabolismo , Ratos , Ratos Long-Evans , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Recidiva , Autoadministração/métodos , Sacarose/administração & dosagem , Edulcorantes/administração & dosagem , Sinaptossomos/metabolismo
18.
Plant Biol (Stuttg) ; 9(2): 342-55, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17236101

RESUMO

Three model communities of trembling aspen (monoculture, and mixed with either paper birch or sugar maple) were grown for seven years in elevated atmospheric CO(2) and O(3) using Free Air CO(2) Enrichment (FACE) technology. We utilized trends in species' importance, calculated as an index of volume growth and survival, as indications of shifting community composition. For the pure aspen communities, different clones emerged as having the highest change in relative importance values depending on the pollutant exposure. In the control and elevated CO(2) treatments, clone 42E was rapidly becoming the most successful clone while under elevated O(3), clone 8 L emerged as the dominant clone. In fact, growth of clone 8 L was greater in the elevated O(3) treatment compared to controls. For the mixed aspen-birch community, importance of aspen and birch changed by - 16 % and + 62 %, respectively, in the controls. In the treatments, however, importance of aspen and birch changed by - 27 % and + 87 %, respectively, in elevated O(3), and by - 10 % and + 45 %, respectively, in elevated CO(2). Thus, the presence of elevated O(3) hastened conversion of stands to paper birch, whereas the presence of elevated CO(2) delayed it. Relative importance of aspen and maple changed by - 2 % and + 3 %, respectively, after seven years in the control treatments. But in elevated O(3), relative importance of aspen and maple changed by - 2 % and + 5 %, respectively, and in elevated CO(2) by + 9 and - 20 %, respectively. Thus, elevated O(3) slightly increases the rate of conversion of aspen stands to sugar maple, but maple is placed at a competitive disadvantage to aspen under elevated CO(2).


Assuntos
Acer/efeitos dos fármacos , Atmosfera , Betula/efeitos dos fármacos , Dióxido de Carbono/farmacologia , Ozônio/farmacologia , Especificidade da Espécie
19.
Plant Physiol ; 137(2): 747-55, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15665240

RESUMO

To function, the catalytic sites of Rubisco (EC 4.1.1.39) need to be activated by the reversible carbamylation of a lysine residue within the sites followed by rapid binding of magnesium. The activation of Rubisco in vivo requires the presence of the regulatory protein Rubisco activase. This enzyme is thought to aid the release of sugar phosphate inhibitors from Rubisco's catalytic sites, thereby influencing carbamylation. In C3 species, Rubisco operates in a low CO2 environment, which is suboptimal for both catalysis and carbamylation. In C4 plants, Rubisco is located in the bundle sheath cells and operates in a high CO2 atmosphere close to saturation. To explore the role of Rubisco activase in C4 photosynthesis, activase levels were reduced in Flaveria bidentis, a C4 dicot, by transformation with an antisense gene directed against the mRNA for Rubisco activase. Four primary transformants with very low activase levels were recovered. These plants and several of their segregating T1 progeny required high CO2 (>1 kPa) for growth. They had very low CO2 assimilation rates at high light and ambient CO2, and only 10% to 15% of Rubisco sites were carbamylated at both ambient and very high CO2. The amount of Rubisco was similar to that of wild-type plants. Experiments with the T1 progeny of these four primary transformants showed that CO2 assimilation rate and Rubisco carbamylation were severely reduced in plants with less than 30% of wild-type levels of activase. We conclude that activase activity is essential for the operation of the C4 photosynthetic pathway.


Assuntos
Flaveria/enzimologia , Regulação da Expressão Gênica de Plantas/fisiologia , Fotossíntese/fisiologia , Proteínas de Plantas/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo , Dióxido de Carbono , Regulação Enzimológica da Expressão Gênica/fisiologia , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , RNA Antissenso
20.
Neurotoxicol Teratol ; 22(5): 703-11, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11106863

RESUMO

Prenatal alcohol exposure can disrupt brain development and lead to a myriad of behavioral alterations, including motor coordination deficits, hyperactivity, and learning deficits. There remains a need, however, to identify treatments and interventions for reducing the severity of alcohol-related neurodevelopmental disorders. Some of the alcohol-induced deficits in learning may be related to alterations in cholinergic functioning. Interestingly, there is a growing literature demonstrating that pre- and/or early postnatal choline supplementation can lead to long-term enhancement in learning and memory and cholinergic activity in rats. The present study examined whether such early choline supplementation might counter the effects of prenatal alcohol treatment on a visuospatial discrimination task. Pregnant Sprague-Dawley rats were randomly assigned to one of three prenatal treatment groups. One group received a liquid diet containing 35% ethanol-derived calories (EDC) from gestational day (GD) 6-20. A second group served as a pair-fed (PF) control group and the third group served as an ad lib lab chow (LC) control. On postnatal day (PD) 2, pups were assigned within-litter to one of three postnatal treatments: choline, saline vehicle, or no treatment. Choline and vehicle pups were intubated with a choline chloride solution or vehicle daily from PD 2 to 21, whereas the non-treated pups were handled daily but not intubated. On PD 45, subjects were tested on a visuospatial discrimination task. Ethanol-exposed subjects who were not treated neonatally with choline committed a significantly greater number of errors both during acquisition and during delayed discrimination training compared to both PF and LC controls. Neonatal choline treatment significantly improved performance on the discrimination task in all groups; however, the beneficial effects of choline were significantly larger in ethanol-exposed subjects. Indeed, the performance of ethanol-exposed pups treated with neonatal choline did not differ from any of the PF or LC groups on any measure. Thus, early postnatal choline supplementation significantly attenuated the effects of prenatal alcohol on this learning task. Importantly, these effects were not due to the acute effects of choline, but rather to long-term changes in brain and behavioral development. These data suggest that early dietary interventions may reduce the severity of fetal alcohol effects.


Assuntos
Depressores do Sistema Nervoso Central/toxicidade , Colina/administração & dosagem , Aprendizagem por Discriminação/efeitos dos fármacos , Etanol/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Animais , Animais Recém-Nascidos , Comportamento Animal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Suplementos Nutricionais , Feminino , Masculino , Gravidez , Ratos
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