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1.
Ethics Med Public Health ; 14: 100516, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32352024

RESUMO

This commentary, on Heine and Quintavalla's article Priorities and Human Rights, considers the authors' position that, while the right to life and other civil and political rights are equally as important as health and other social rights, some degree of prioritizing types of rights is necessary because all rights cannot be implemented simultaneously. This commentary concurs with Heine and Quintavalla's challenge to the common argument that civil and political rights are of higher importance (Phillips J, 2013; Farer T, 1992; Koji T, 2001). But this commentary goes further, in suggesting that before a society begins to prioritize implementation of human rights, it must first secure the basic understanding that the right to health is indeed equally important to civil and political rights. This commentary uses the example of national courts to show how judicial engagement with the right to health has begun to chip away at the boundary between the categories of rights. It suggests that greater interconnection among health and other rights has also made mapping out a hierarchical relationship far more difficult. Thus, before implementation can have any defined order, states must first come to a shared understanding regarding the equal if not greater importance of the right to health.


Ce commentaire, qui porte sur l'article de Heine et Quintavalla, intitulé « Priorités et droits de l'homme ¼, examine la position des auteurs selon laquelle si le droit à la vie et les autres droits civils et politiques sont aussi importants que la santé et les autres droits sociaux, il est nécessaire de hiérarchiser les types de droits dans une certaine mesure, car tous les droits ne peuvent être mis en œuvre simultanément. Ce commentaire rejoint la contestation par Heine et Quintavalla de l'argument commun selon lequel les droits civils et politiques sont d'une importance supérieure (Phillips J, 2013; Farer T, 1992; Koji T, 2001). Mais ce commentaire va plus loin, en suggérant qu'avant qu'une société ne commence à donner la priorité à la mise en œuvre des droits de l'homme, elle doit d'abord s'assurer que le droit à la santé est effectivement aussi important que les droits civils et politiques. Ce commentaire utilise l'exemple des tribunaux nationaux pour montrer comment l'engagement judiciaire en faveur du droit à la santé a commencé à effacer la frontière entre les catégories de droits. Il suggère qu'une plus grande interconnexion, entre le droit à la santé et les autres droits, a également rendu beaucoup plus difficile l'établissement d'une relation hiérarchique. Ainsi, avant que la mise en œuvre puisse avoir un ordre défini, les États doivent d'abord parvenir à une compréhension commune de l'importance égale, voire supérieure, du droit à la santé.

2.
Sci Adv ; 5(9): eaaw5549, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31517047

RESUMO

Nakhlite meteorites are ~1.4 to 1.3 Ga old igneous rocks, aqueously altered on Mars ~630 Ma ago. We test the theory that water-rock interaction was impact driven. Electron backscatter diffraction demonstrates that the meteorites Miller Range 03346 and Lafayette were heterogeneously deformed, leading to localized regions of brecciation, plastic deformation, and mechanical twinning of augite. Numerical modeling shows that the pattern of deformation is consistent with shock-generated compressive and tensile stresses. Mesostasis within shocked areas was aqueously altered to phyllosilicates, carbonates, and oxides, suggesting a genetic link between the two processes. We propose that an impact ~630 Ma ago simultaneously deformed the nakhlite parent rocks and generated liquid water by melting of permafrost. Ensuing water-rock interaction focused on shocked mesostasis with a high density of reactive sites. The nakhlite source location must have two spatially correlated craters, one ~630 Ma old and another, ejecting the meteorites, ~11 Ma ago.

3.
HIV Med ; 20(7): 450-455, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31034141

RESUMO

OBJECTIVES: In the late 1990s, when the current Russian opioid epidemic began, illicit opioids used in Russia consisted almost exclusively of heroin. The type of opioids used has evolved in the early 21st Century. The objective of this study was to describe the evolution of illicit opioid use among people living with HIV (PLWH) reporting recent opioid use in St Petersburg, Russia. METHODS: We examined baseline data from four research studies conducted in the period 2004-2015 that included PLWH who used opioids [Partnership to Reduce the Epidemic Via Engagement in Narcology Treatment (PREVENT; 2004-2005; n = 17), HIV Evolution in Russia-Mitigating Infection Transmission and Alcoholism in a Growing Epidemic (HERMITAGE; 2007-2010; n = 281), Linking Infectious and Narcology Care (LINC; 2013-2014; n = 119) and Russia Alcohol Research Collaboration on HIV/AIDS (Russia ARCH; 2012-2015; n = 121)] and reported recent use of heroin and other opioids. RESULTS: Although these studies spanned more than a decade, the participants represented similar birth cohorts; the mean age was 24.5 years in 2004 and 33.3 years in 2014. The use of opioid types, however, evolved across cohorts, with the use of any illicit drug other than heroin increasing from 6% [95% confidence interval (CI) 000.2, 29%] in PREVENT (2004-2005) to 30% (95% CI 25, 36%) in HERMITAGE (2007-2010) to 70% (95% CI 61, 78%) in LINC (2013-2014) to 77% (95% CI 68, 84%) in ARCH (2012-2015). Any heroin use consistently decreased over the 10-year period in the cohorts, from 100% (95% CI 80, 100%) in 2004-2005 to 54% (95% CI 44, 63%) in 2012-2015. CONCLUSIONS: Among PLWH who use opioids in St Petersburg, Russia, illicit use of opioids other than heroin appears to be more common than heroin use.


Assuntos
Infecções por HIV/epidemiologia , Heroína , Abuso de Substâncias por Via Intravenosa/epidemiologia , Adulto , Analgésicos Opioides , Estudos de Coortes , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Federação Russa/epidemiologia , Abuso de Substâncias por Via Intravenosa/classificação , Adulto Jovem
4.
Am J Transplant ; 6(8): 1882-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16889543

RESUMO

The purpose of this study is to determine the role of liver biopsy and outcome of patients undergoing donor evaluation for adult-to-adult right hepatic lobe living donor liver transplantation (LDLT). Records of patients presenting for a comprehensive donor evaluation between 1997 and February 2005 were reviewed. Liver biopsy was performed only in patients with risk factors for abnormal histology. Two hundred and sixty patients underwent a comprehensive donor evaluation and 116 of 260 (45%) were suitable for donation, 14 of 260 (5.4%) did not complete evaluation and 130 of 260 (50%) were rejected. Four patients underwent unsuccessful hepatectomy surgery due to discovery of intraoperative abnormalities. Between 1997 and 2001, the acceptance rate of donor candidates (63%) was higher than 2002-2005 (36%), p < 0.0001. Sixty-six of the 150 eligible patients (44%) fulfilled criteria for liver biopsy and 28 of 66 (42%) had an abnormal finding. Less than half of the patients undergoing donor evaluation were suitable donors and the donor acceptance rate has declined over time. A large proportion of the patients undergoing liver biopsy have abnormal findings. Our evaluation process failed to identify 4 of 103 who had aborted donor surgeries.


Assuntos
Seleção do Doador/métodos , Transplante de Fígado , Doadores Vivos , Adolescente , Adulto , Biópsia , Seleção do Doador/normas , Feminino , Humanos , Transplante de Fígado/estatística & dados numéricos , Doadores Vivos/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
5.
J Struct Biol ; 147(2): 185-99, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15193647

RESUMO

This study investigated how effectively a laboratory microCT (X-ray micro-computed tomography) system can quantify bone resorption in an in vitro calvarial model and how well this measure correlates with a conventional assay for calcium release (fluorometric titration). In vitro bone resorption in neonatal murine calvaria was quantified for 0.3 or 1.0 nM interleukin-1 (IL-1) or for 1.0 or 10.0 nM parathyroid hormone (PTH) treatment. Compared to control calvaria, a significantly greater fraction F of the calvarial "shell" (computed from the volumetric microCT data) was resorbed in treated calvaria of 5- to 7-day-old pups from the same litter. Excellent correlation (R2 = 0.8234) was observed between F and calcium release, and, unlike the calcium assay, the 3-D maps revealed where bone was resorbed. Mineral was preferentially lost near the sutures, and areas away from the suture were left relatively intact. MicroCT of calvaria before and after 96 h culture demonstrated that this X-irradiation neither increased control resorption nor prevented responses in the treated calvaria. Observations on calvaria from intact mice aged 1, 3, 5, 8, and 11 days showed uniformly distributed mineral (not a pronounced patchwork of "high" and "low" mineral regions) and increasing levels of mineral with age; this suggested that the spatial patterns of resorption were not related to inhomogeneities in the starting mineral distribution.


Assuntos
Reabsorção Óssea/diagnóstico por imagem , Interleucina-1/farmacologia , Hormônio Paratireóideo/farmacologia , Tomografia Computadorizada por Raios X/métodos , Animais , Reabsorção Óssea/metabolismo , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Cálcio/análise , Cálcio/metabolismo , Flúor/análise , Flúor/metabolismo , Camundongos , Minerais/análise , Minerais/metabolismo , Crânio/diagnóstico por imagem , Crânio/efeitos dos fármacos , Crânio/metabolismo
6.
Minerva Chir ; 58(5): 725-40, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14603151

RESUMO

This article highlights the currently available immunosuppressive medications that are used to prevent or treat hepatic allograft rejection. Currently-available immunosuppressive medications are highly effective in prevention of allograft rejection, graft loss, and patient death. However, side effects of medications are common, usually dose-related, and specific to the administered drug. Maintenance immunosuppression which has been primarily based upon calcineurin inhibitors (Cyclosporine, CsA, or tacrolimus, Tac) is commonly modified to reduce metabolic complications of therapy. Toxic consequences of steroids may be ameliorated by steroid withdrawal without risk of acute rejection or immunologic graft loss. Calcineurin-sparing regimens may include use of mycophenolate mofetil (MMF) or sirolimus, and allow reduction in doses and plasma levels of CsA and Tac. Recurrence of hepatitis C is universal after liver transplantation and progresses rapidly, compared to its natural history in non-immunocompromised patients. Unfortunately, no single immunosuppressive agent or strategy has yet been shown to convincingly modify the course of post-transplant recurrence. Most centers manage recurrenc hepatitis C by either steroid avoidance, reduction in immunosuppression, or institution of antiviral therapy. Ongoing advances in immunosuppressive and antiviral medications will allow tailoring of the immunosuppressive prescription, which undoubtedly will benefit current and future liver recipients.


Assuntos
Terapia de Imunossupressão , Transplante de Fígado/imunologia , Inibidores de Calcineurina , Glucocorticoides/uso terapêutico , Hepatite C/cirurgia , Humanos , Recidiva , Sirolimo/uso terapêutico
7.
Brain Res Bull ; 54(5): 565-8, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11397549

RESUMO

Free radical-induced oxidative damage may be involved in the neurodegenerative process associated with Alzheimer's disease (AD). 8-Isoprostaglandin F(2alpha) (iPF(2alpha)-III) is an isoprostane derived from free radical-induced non-enzymatic oxidation of arachidonic acid. It is formed in vivo and is an indicator of lipid peroxidation. Measurements were made of iPF(2alpha)-III in the urine of patients with mild to moderate dementia associated with probable AD and compared to those in the urine of non-demented subjects, who were similar in age and gender. 2,3-Dinor thromboxane B(2) (dinor TXB(2)), a urinary metabolite of TXB(2) was also measured, and served as an indicator of the enzymatic transformation of a product of arachidonic acid. Enzyme linked immunoassays were used to measure iPF(2alpha)-III and dinor TXB(2) in the urine. The concentration of iPF(2alpha)-III was significantly elevated in urine of patients assessed to have mild to moderate dementia as compared to non-demented patients. The concentration of urinary dinor TXB(2) was also significantly elevated in the patients with dementia and probable AD as compared to the non-demented subjects. There was considerable overlap of values obtained for demented and non-demented patients for iPF(2alpha)-III and dinor TXB(2), respectively. The observed elevation of iPF(2alpha)-III suggests that patients with mild to moderate dementia associated with probable AD are experiencing significant oxidative stress. This finding is consistent with current data suggesting that oxidative stress may be occurring in patients with dementia and probable AD. The increase of dinor TXB(2) may indicate that enzymatic processes related to the metabolism of arachidonic acid-derived products are also increased in demented patients with probable AD.


Assuntos
Doença de Alzheimer/urina , Dinoprosta/urina , Peroxidação de Lipídeos/fisiologia , Degeneração Neural/urina , Tromboxano B2/urina , Idoso , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/fisiopatologia , Creatinina/urina , Dinoprosta/análogos & derivados , F2-Isoprostanos , Feminino , Humanos , Masculino , Degeneração Neural/fisiopatologia , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo/fisiologia , Tromboxano B2/análogos & derivados
9.
Am J Crit Care ; 10(1): 4-10, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11153183

RESUMO

BACKGROUND: Depressive symptoms are an independent risk factor for outcome in patients with cardiac disease, but their effect on outcome among patients undergoing coronary artery bypass grafting is not well understood. OBJECTIVES: To determine whether or not clinical variables including length of stay, readmission rates, and mortality are related to patients' level of depressive symptoms before and after coronary artery bypass grafting. METHODS: An observational, longitudinal design was used. The Medical Outcomes Study 36-item short-form health survey was used to collect data on depressive symptoms in 416 patients undergoing coronary artery bypass grafting. The distribution of depressive symptoms was correlated with length of stay after the procedure, readmission, and mortality. RESULTS: The level of depressive symptoms before coronary artery bypass grafting correlated with the level of depressive symptoms at 6 weeks follow-up, both for the individual items "feeling down in the dumps" (r = 0.24, P = .009) and "feeling downhearted" (r = 0.36, P < .001) and for the overall score on the Mental Health scale (r = 0.40, P < .001). Feeling down in the dumps (P = .007) and overall scores on the Mental Health scale (P = .02) were significantly related to readmission within 6 months. CONCLUSIONS: Higher levels of depressive symptoms before coronary artery bypass grafting are related to higher hospital readmission rates 6 months after the procedure. Nurses can play a pivotal role in determining which patients require evaluation, educating patients, and initiating effective treatment, which may prevent readmission related to depressive symptoms.


Assuntos
Ponte de Artéria Coronária/psicologia , Doença das Coronárias/psicologia , Doença das Coronárias/cirurgia , Depressão/complicações , Idoso , Fatores de Confusão Epidemiológicos , Doença das Coronárias/mortalidade , Feminino , Inquéritos Epidemiológicos , Humanos , Tempo de Internação , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Observação , Readmissão do Paciente , Fatores de Risco , Inquéritos e Questionários , Resultado do Tratamento
10.
J Am Osteopath Assoc ; 101(12 Suppl Pt 1): S11-5, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11794746

RESUMO

There is increasing evidence that free radical-induced oxidative damage may play a role in the pathogenesis of Alzheimer's disease. Free radicals are reactive oxygen compounds that may attack and damage lipids, proteins, and DNA. The brain is especially sensitive to oxidative damage because of its high content of readily oxidized fatty acids, high use of oxygen, and low levels of antioxidants. Evidence for oxidative damage has been obtained from postmortem brain tissue as well as from living patients with Alzheimer's disease. Antioxidants such as vitamin E show promise that they may help in treating the disease.


Assuntos
Doença de Alzheimer/etiologia , Antioxidantes/administração & dosagem , Radicais Livres/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Idoso , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Medição de Risco , Sensibilidade e Especificidade
11.
J Am Osteopath Assoc ; 100(6): 349-50, 355-9, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10902406

RESUMO

Physician-assisted suicide (PAS) was legalized in Oregon in 1997. In the study reported here, the authors surveyed a sample of New Jersey physicians with regard to Oregon's Death with Dignity Act and to whether similar legislation should be enacted in New Jersey. A 49-item questionnaire was sent to 563 physicians in New Jersey who were licensed in the specialties of family practice, internal medicine, surgery, psychiatry, and obstetrics/gynecology. The questionnaire contained sections pertaining to demographics, physicians' attitudes regarding PAS, and physicians' opinions on Oregon's Death with Dignity Act. A brief summary of the legislation was included in the mailing, which participants were asked to read before completing the questionnaire. Of the 191 physicians who responded to the survey, 55% agreed with legislation that would legalize PAS, and 59% said that a law similar to that enacted in Oregon should exist in New Jersey. However, only 47% of respondents indicated that they believed PAS to be consistent with the role of a physician to relieve pain and suffering. Slightly more than half of respondents indicated that they would refuse to participate in PAS and were concerned about issues such as professional and personal liability and the potential for abuse. Physicians in New Jersey will require additional information, education, and discussion of the ethical and legal implications of PAS before a law similar to that in Oregon could be proposed or considered.


Assuntos
Ética Médica , Médicos/estatística & dados numéricos , Suicídio Assistido/legislação & jurisprudência , Idoso , Atitude do Pessoal de Saúde , Coleta de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , New Jersey , Oregon , Direito a Morrer , Inquéritos e Questionários
13.
Acta Haematol ; 102(3): 148-51, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10692679

RESUMO

Ozone autohemotherapy has been considered a form of alternative medicine and has not yet been subjected to the rigors of well-designed clinical trials. Despite encouraging anecdotal reports regarding the use of ozone in various disorders, there has been a concern that ozone per se may adversely affect red cell membranes and metabolites. The purpose of this study was to ascertain the effect of ozone administration at a concentration commonly used in autohemotherapy on a panel of red cell enzymes and intermediates, as well as its effect on red cell integrity. Since these parameters were unaffected by ozone, we suggest that clinical trials for the use of ozone autohemotherapy should be encouraged.


Assuntos
Eritrócitos/efeitos dos fármacos , Oxidantes Fotoquímicos/farmacologia , Ozônio/farmacologia , Trifosfato de Adenosina/metabolismo , Eritrócitos/enzimologia , Eritrócitos/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Técnicas In Vitro , Oxidantes Fotoquímicos/efeitos adversos , Ozônio/efeitos adversos
14.
Ann Intern Med ; 132(2): 118-21, 2000 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-10644272

RESUMO

BACKGROUND: Rosiglitazone maleate is the second approved oral hypoglycemic agent of the thiazolidinedione class. The first, troglitazone, has been associated with liver failure, occasionally resulting in liver transplantation or death. There have been no reports to date of rosiglitazone-associated elevations in the alanine aminotransferase level or hepatotoxicity. OBJECTIVE: To report the clinical characteristics of liver failure developing in a patient receiving rosiglitazone. DESIGN: Case report. SETTING: University hospital. PATIENT: 69-year-old man taking rosiglitazone, 4 mg/d. INTERVENTION: Discontinuation of rosiglitazone therapy and treatment with lactulose, vitamin K, fresh frozen plasma, ventilatory assistance, and intensive care unit support. MEASUREMENTS: Blood test monitoring, including toxicology screening, liver function tests, coagulation studies, serum chemistries, and complete blood counts. RESULTS: After 21 days of rosiglitazone therapy, hepatic failure developed. Other causes of hepatic failure, such as viruses and toxins, were excluded, although it is possible that congestive heart failure was also a causative factor. The patient recovered fully with supportive care. CONCLUSION: Rosiglitazone may be associated with hepatic failure.


Assuntos
Hipoglicemiantes/efeitos adversos , Falência Hepática/induzido quimicamente , Tiazóis/efeitos adversos , Tiazolidinedionas , Idoso , Terapia Combinada , Doença das Coronárias/complicações , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Interações Medicamentosas , Humanos , Isquemia/complicações , Fígado/irrigação sanguínea , Falência Hepática/diagnóstico , Falência Hepática/terapia , Masculino , Monitorização Fisiológica , Pravastatina/uso terapêutico , Rosiglitazona , Verapamil/uso terapêutico
15.
Arch Intern Med ; 159(19): 2349-56, 1999 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-10547175

RESUMO

BACKGROUND: Previous observational and interventional studies have suggested that regular physical exercise may be associated with reduced symptoms of depression. However, the extent to which exercise training may reduce depressive symptoms in older patients with major depressive disorder (MDD) has not been systematically evaluated. OBJECTIVE: To assess the effectiveness of an aerobic exercise program compared with standard medication (ie, antidepressants) for treatment of MDD in older patients, we conducted a 16-week randomized controlled trial. METHODS: One hundred fifty-six men and women with MDD (age, > or = 50 years) were assigned randomly to a program of aerobic exercise, antidepressants (sertraline hydrochloride), or combined exercise and medication. Subjects underwent comprehensive evaluations of depression, including the presence and severity of MDD using Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria and Hamilton Rating Scale for Depression (HAM-D) and Beck Depression Inventory (BDI) scores before and after treatment. Secondary outcome measures included aerobic capacity, life satisfaction, self-esteem, anxiety, and dysfunctional cognitions. RESULTS: After 16 weeks of treatment, the groups did not differ statistically on HAM-D or BDI scores (P = .67); adjustment for baseline levels of depression yielded an essentially identical result. Growth curve models revealed that all groups exhibited statistically and clinically significant reductions on HAM-D and BDI scores. However, patients receiving medication alone exhibited the fastest initial response; among patients receiving combination therapy, those with less severe depressive symptoms initially showed a more rapid response than those with initially more severe depressive symptoms. CONCLUSIONS: An exercise training program may be considered an alternative to antidepressants for treatment of depression in older persons. Although antidepressants may facilitate a more rapid initial therapeutic response than exercise, after 16 weeks of treatment exercise was equally effective in reducing depression among patients with MDD.


Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo/terapia , Exercício Físico , Idoso , Ansiedade , Cognição , Terapia Combinada , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/fisiopatologia , Transtorno Depressivo/psicologia , Feminino , Humanos , Pulmão/fisiopatologia , Medidas de Volume Pulmonar , Masculino , Pessoa de Meia-Idade , Aptidão Física , Qualidade de Vida , Autoimagem , Índice de Gravidade de Doença
16.
Life Sci ; 64(21): 1877-87, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10353586

RESUMO

Inhibition of nitric oxide synthase (NOS) activity results in opioid-mediated supraspinal analgesia in the rat, as indicated by increased reaction time in the hot plate test. It is documented that a relationship exists between NMDA receptor activation and the activity of NOS. The present investigation sought to determine if inactivation of the NMDA receptor produced antinociception of supraspinal origin, as was observed in response to inhibition of NOS, and if this response was mediated by brain opioids, by activation of receptors for the neurotransmitter, dopamine, or both. Administration of MK-801, a non-competitive antagonist of the NMDA receptor, produced significant antinociception as measured by reaction time in the hot plate test of analgesia. Antinociception resulting from treatment with MK-801 appeared to be mediated by brain opioids, as indicated by the ability of the opioid antagonist, naloxone, to partially reverse the effect of MK-801 administration. This analgesic response was also partially diminished by administration of the dopamine D1 receptor antagonist, SCH 23390 and the dopamine D2 receptor antagonist, sulpiride. The analgesia resulting from NMDA receptor antagonism was found to be only partially attributable to dopamine and brain opioids, since co-administration of naloxone and SCH 23390 or naloxone and sulpiride, were unable to completely reverse the antinociceptive response to MK-801. The present findings suggest that inhibition of NMDA receptor activity produces supraspinal analgesia. Furthermore, it appears that antinociception induced by blockade of the NMDA receptor results, at least in part, from activation of endogenous brain opioids and stimulation of D1 and D2 subtypes of the dopamine receptor.


Assuntos
Analgésicos não Narcóticos/farmacologia , Encéfalo/efeitos dos fármacos , Antagonistas de Aminoácidos Excitatórios/farmacologia , Peptídeos Opioides/fisiologia , Receptores Dopaminérgicos/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Animais , Benzazepinas/farmacologia , Maleato de Dizocilpina/farmacologia , Masculino , Naloxona/farmacologia , Óxido Nítrico Sintase/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Sulpirida/farmacologia
17.
Methods Mol Biol ; 120: 107-18, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10343314

RESUMO

Enzyme immunoassay of eicosanoids is a nonradioactive, highly sensitive method of determining the concentration of eicosanoids in biological samples. Although relatively easy to use, the assays require a high level of precise pipetting technique and familiarity with critical points in the assay procedure. Although assay kits complete with plates, buffers, antibodies, tracers, and color development reagents are available, it is more economical to develop the assay within the laboratory if the assay is to be performed routinely. The only major disadvantage with EIA is that the investigator is limited to measuring eicosanoids with commercially available enzyme-tracers and antibodies. The labeling of particular eicosanoids by enzyme tracers is rarely, if ever, performed outside of industry. Growing of antibodies is conducted in many laboratories but is beyond the scope of this chapter. It requires a significant level of commitment of time and resources to establish the specificity of the antibody (i.e., does the antibody cross-react with eicosanoids of similar structure). Furthermore, this will not solve the problem of availability of eicosanoid-tracer. On the other hand, it must be noted that with the exception of the cytochrome P-450 metabolites of arachidonic acid, most of the major eicosanoids that are biologically active and are known to play regulatory roles in physiology and/or pathology, have commercially available antibodies and enzyme-tracers.


Assuntos
Eicosanoides/análise , Técnicas Imunoenzimáticas/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Diabetes ; 48(3): 603-8, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10078563

RESUMO

Heterogeneous myocardial sympathetic denervation complicating diabetes has been invoked as a factor contributing to sudden unexplained cardiac death. In subjects with diabetic autonomic neuropathy (DAN), distal left ventricular (LV) denervation contrasts with preservation of islands of proximal innervation, which exhibit impaired vascular responsiveness. The aims of this study were to determine whether this heterogeneous pattern of myocardial sympathetic denervation occurs in a rat model of diabetes and to explore a potential association with regional fluctuations in myocardial nerve growth factor (NGF) protein. Myocardial sympathetic denervation was characterized scintigraphically using the sympathetic neurotransmitter analog C-11 hydroxyephedrine ([11C]HED) and compared with regional changes in myocardial NGF protein abundance and norepinephrine content after 6 and 9 months in nondiabetic (ND) and streptozotocin-induced diabetic (STZ-D) rats. In ND rats, no difference in [11C]HED retention or norepinephrine content was detected in the proximal versus distal myocardium. After 6 months, compared with ND rats, myocardial [11C]HED retention had declined in the proximal segments of STZ-D rats by only 9% (NS) compared with a 33% decrease in the distal myocardium (P < 0.05). Myocardial norepinephrine content was similar in both ND and STZ-D rats. At 6 months, LV myocardial NGF protein content in STZ-D rats decreased by 52% in the proximal myocardial segments (P < 0.01 vs. ND rats) and by 82% distally (P < 0.01 vs. ND rats, P < 0.05 vs. proximal segments). By 9 months, [11C]HED retention had declined in both the proximal and distal myocardial segments of the STZ-D rats by 42% (P < 0.01 vs. ND rats), and LV norepinephrine content and NGF protein were decreased in parallel. Therefore, 6 months of STZ-induced diabetes results in heterogeneous cardiac sympathetic denervation in the rat, with maximal denervation occurring distally, and is associated with a proximal-to-distal gradient of LV NGF protein depletion. It is tempting to speculate that regional fluctuations of NGF protein in the diabetic myocardium contribute to heterogeneous cardiac sympathetic denervation complicating diabetes.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Neuropatias Diabéticas/fisiopatologia , Miocárdio/metabolismo , Fatores de Crescimento Neural/metabolismo , Sistema Nervoso Simpático/fisiopatologia , Animais , Glicemia/metabolismo , Peso Corporal , Radioisótopos de Carbono/farmacocinética , Denervação , Diabetes Mellitus Experimental/metabolismo , Neuropatias Diabéticas/metabolismo , Efedrina/análogos & derivados , Efedrina/farmacocinética , Coração/diagnóstico por imagem , Coração/inervação , Coração/fisiopatologia , Masculino , Norepinefrina/metabolismo , Cintilografia , Ratos , Ratos Wistar , Distribuição Tecidual , Função Ventricular
19.
Cell Death Differ ; 5(11): 984-95, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9846185

RESUMO

The product of the ras proto-oncogene has been implicated as an essential signal transducer, involved in a variety of biological or pathological activities, including apoptosis. The aim of this investigation was to further explore the mechanisms of apoptosis triggered by Ras. Stable expression of constitutively-activated (v)-Ki-Ras in Balb/c-3T3 mouse fibroblasts resulted in a loss of G1 arrest in response to treatments which induced cell cycle arrest in the parental Balb/c-3T3 cells, accompanied by decreased expression of the p53 tumor suppressor protein and the GADD45 gene, the product of which is involved in DNA repair, and deregulated expression of the MDM-2 gene, the product of which can regulate p53 expression. Ki-Ras expression also increased the frequency of PALA-selectable CAD gene amplification, and paradoxically the susceptibility to PALA-induced apoptosis. After persistent serum-starvation, cells expressing the activated ras gene lost clonogenic potential, indicating impaired capability for genetic repair in the cells. Taken together, these data suggest that activated Ki-ras may confer genetic instabilty upon cells, possibly through interference with tumor suppressors, such as p53. While this instability may facilitate adaptation to environmental stresses, this instability in the genome also renders cells containing activated ras genes intrinsically more susceptible to programmed cell death, possibly by accumulation of undesirable or lethal genetic events during the process of tumor development.


Assuntos
Apoptose/genética , Genes ras , Proteínas Nucleares , Células 3T3 , Animais , Apoptose/efeitos dos fármacos , Aspartato Carbamoiltransferase/genética , Ácido Aspártico/análogos & derivados , Ácido Aspártico/farmacologia , Carbamoil Fosfato Sintase (Glutamina-Hidrolizante)/genética , Ensaio de Unidades Formadoras de Colônias , Meios de Cultura Livres de Soro , Reparo do DNA/genética , Di-Hidro-Orotase/genética , Fase G1/efeitos dos fármacos , Fase G1/genética , Amplificação de Genes , Expressão Gênica , Genes p53 , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Complexos Multienzimáticos/genética , Ácido Fosfonoacéticos/análogos & derivados , Ácido Fosfonoacéticos/farmacologia , Proteínas/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-mdm2 , Transdução de Sinais , Proteínas GADD45
20.
J Lab Clin Med ; 132(6): 519-29, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9851743

RESUMO

The exposure of endothelial cells to hypoxic environments regulates the expression of a number of genes with products that are vasoactive or mitogenic for vascular tissue, including platelet-derived growth factor, endothelin-1, and endothelial nitric oxide synthase. Hypoxia is also known to alter the adhesive properties of endothelium toward a variety of blood cell types. Thrombospondin-1 (TSP-1) is a glycoprotein with major roles in cellular adhesion and vascular smooth muscle proliferation and migration. We report here that hypoxia induces TSP-1 gene and protein expression. Oxygen tensions of < or =30 torr resulted in TSP-1 transcript induction initially apparent at 1 to 6 hours, with maximal induction (6.5-fold+/-1.2-fold) within 24 to 48 hours in both human and bovine endothelial cells. TSP-1 protein levels remain elevated after 72 hours of continuous hypoxic exposure. The induction of TSP-1 steady-state transcript levels is caused in large part, if not entirely, by post-transcriptional stabilization of the TSP-1 mRNA. The TSP-1 induction by hypoxia is a graded and reversible physiologic response and can be mimicked by the use of cobalt chloride or the inhibition of nitric oxide production, suggesting both the involvement of a heme-containing oxygen sensor and a role for the endogenous production of nitric oxide in TSP-1 regulation. The effects of hypoxia both on the stabilization of the TSP-1 transcript and the stimulation of TSP-1 protein production are completely inhibited by arginine butyrate.


Assuntos
Endotélio Vascular/metabolismo , Regulação da Expressão Gênica , Hipóxia/metabolismo , Trombospondina 1/genética , Trombospondina 1/metabolismo , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Butiratos/farmacologia , Bovinos , Células Cultivadas , Cobalto/farmacologia , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Humanos , Ácidos Hidroxâmicos/farmacologia , NG-Nitroarginina Metil Éster/farmacologia , Oxigênio/metabolismo , RNA Mensageiro/metabolismo
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