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1.
J Med Biogr ; 27(2): 67-75, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-27885153

RESUMO

Karl Landsteiner applied the sciences of biochemistry, pathology, microbiology, and immunology in medical research to great success during the first half of the 20th century. Although he is principally known for elucidating the major blood group antigens A and B and their isoantibodies for which he was awarded the Nobel Prize in Physiology or Medicine, Landsteiner made many other important medical discoveries. In that respect, he ascertained that paralytic poliomyelitis was due to a virus, the pancreas was damaged in cystic fibrosis, simple chemicals called haptens were able to combine with antibodies, and the Rh antigen that was later found to be the principal cause of hemolytic anemia of the newborn was found in most humans. Moreover, Landsteiner's book "The Specificity of Serological Reactions" was a precursor to the molecular revolution in immunology that occurred after Second World War. Finally, he was one of the leaders of the American Association of Immunology and of the Journal of Immunology.


Assuntos
Alergia e Imunologia/história , Bioquímica/história , Médicos/história , Áustria , Antígenos de Grupos Sanguíneos/história , Europa (Continente) , História do Século XIX , História do Século XX , New York , Sorologia/história
2.
J Med Biogr ; 24(4): 452-459, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26508622

RESUMO

In 2003, we published evidence that the most likely cause of FDR's 1921 neurological disease was Guillain-Barré syndrome. Afterwards, several historians and neurologists stated in their publications that FDR had paralytic poliomyelitis. However, significant criticism of our article or new support for that diagnosis was not revealed. One critic claimed that FDR's cerebrospinal fluid indicated poliomyelitis, but we did not find evidence that a lumbar puncture was performed. The diagnosis of FDR's neurological disease still depends upon documented clinical abnormalities. His age, prolonged symmetric ascending paralysis, transient numbness, protracted dysaesthesia (pain on slight touch), facial paralysis, bladder and bowel dysfunction, and absence of meningismus are typical of Guillain-Barré syndrome and are inconsistent with paralytic poliomyelitis. FDR's prolonged fever was atypical for both diseases. Finally, permanent paralysis, though commoner in paralytic poliomyelitis, is frequent in Guillain-Barré syndrome. Thus, the clinical findings indicate the most likely diagnosis in FDR's case remains Guillain-Barré syndrome.


Assuntos
Pessoas Famosas , Síndrome de Guillain-Barré/história , Poliomielite/história , Política , Diagnóstico Diferencial , História do Século XX , Humanos , Masculino
3.
Burns ; 38(7): 1072-8, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22647495

RESUMO

INTRODUCTION: Acute lung injury (ALI) and sepsis are major contributors to the morbidity and mortality of critically ill patients. The current study was designed further evaluate the mechanism of pulmonary vascular hyperpermeability in sheep with these injuries. METHODS: Sheep were randomized to a sham-injured control group (n=6) or ALI/sepsis group (n=7). The sheep in the ALI/sepsis group received inhalation injury followed by instillation of Pseudomonas aeruginosa into the lungs. These groups were monitored for 24 h. Additional sheep (n=16) received the injury and lung tissue was harvested at different time points to measure lung wet/dry weight ratio, vascular endothelial growth factor (VEGF) mRNA and protein expression as well as 3-nitrotyrosine protein expression in lung homogenates. RESULTS: The injury induced severe deterioration in pulmonary gas exchange, increases in lung lymph flow and protein content, and lung water content (P<0.01 each). These alterations were associated with elevated lung and plasma nitrite/nitrate concentrations, increased tracheal blood flow, and enhanced VEGF mRNA and protein expression in lung tissue as well as enhanced 3-nitrotyrosine protein expression (P<0.05 each). CONCLUSIONS: This study describes the time course of pulmonary microvascular hyperpermeability in a clinical relevant large animal model and may improve the experimental design of future studies.


Assuntos
Lesão Pulmonar Aguda , Permeabilidade Capilar , Pneumonia , RNA Mensageiro/análise , Lesão por Inalação de Fumaça , Fator A de Crescimento do Endotélio Vascular/metabolismo , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/fisiopatologia , Animais , Modelos Animais de Doenças , Feminino , Pulmão/metabolismo , Pulmão/fisiopatologia , Microcirculação , Óxido Nítrico/metabolismo , Pneumonia/complicações , Pneumonia/metabolismo , Pneumonia/fisiopatologia , Infecções por Pseudomonas/complicações , Infecções por Pseudomonas/metabolismo , Infecções por Pseudomonas/fisiopatologia , Pseudomonas aeruginosa , Circulação Pulmonar , Edema Pulmonar/etiologia , Edema Pulmonar/metabolismo , Edema Pulmonar/fisiopatologia , Troca Gasosa Pulmonar , Sepse/complicações , Sepse/metabolismo , Sepse/fisiopatologia , Ovinos , Lesão por Inalação de Fumaça/complicações , Lesão por Inalação de Fumaça/metabolismo , Lesão por Inalação de Fumaça/fisiopatologia , Fatores de Tempo , Tirosina/análogos & derivados , Tirosina/metabolismo
4.
Shock ; 37(5): 468-72, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22266977

RESUMO

The formation of oxidative stress in the lung and activation of neutrophils are major determinants in the development of respiratory failure after acute lung injury and sepsis. However, the time changes of these pathogenic factors have not been sufficiently described. Twenty-four chronically instrumented sheep were subjected to cotton smoke inhalation injury and instillation of live Pseudomonas aeruginosa into both lungs. The sheep were euthanized at 4, 8, 12, 18, and 24 h after injury. Additional sheep received sham injury and were euthanized after 24 h. Pulmonary function was assessed by determination of oxygenation index and pulmonary shunt fraction. In addition, lung tissue was harvested at the respective time points for the measurement of malondialdehyde, interleukin 6, poly(ADP ribose), myeloperoxidase, and alveolar polymorphonuclear neutrophil score. The injury induced severe respiratory failure that was associated with an early increase in lipid peroxidation and interleukin 6 expression. The injury further led to an increase in poly(ADP ribose) activity that reached its peak at 12 h after injury and declined afterward. In addition, progressive increases in markers of neutrophil accumulation in the lung were observed. The peak of neutrophil accumulation in the lung was associated with a severe depletion of circulating neutrophils. The results from our model may enhance the understanding of the pathophysiological alterations after acute lung injury and sepsis and thus be useful in exploring therapeutic interventions directed at modifying the expression or activation of inflammatory mediators.


Assuntos
Lesão Pulmonar Aguda/imunologia , Ativação de Neutrófilo/imunologia , Neutrófilos/imunologia , Estresse Oxidativo/imunologia , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Animais , Modelos Animais de Doenças , Regulação da Expressão Gênica/imunologia , Mediadores da Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Interleucina-6/imunologia , Interleucina-6/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Malondialdeído/imunologia , Malondialdeído/metabolismo , Neutrófilos/metabolismo , Peroxidase/imunologia , Peroxidase/metabolismo , Poli Adenosina Difosfato Ribose/imunologia , Poli Adenosina Difosfato Ribose/metabolismo , Infecções por Pseudomonas/imunologia , Infecções por Pseudomonas/metabolismo , Infecções por Pseudomonas/patologia , Pseudomonas aeruginosa , Ovinos , Lesão por Inalação de Fumaça/imunologia , Lesão por Inalação de Fumaça/metabolismo , Lesão por Inalação de Fumaça/patologia , Fatores de Tempo
5.
Crit Care Med ; 39(2): 357-63, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21057315

RESUMO

OBJECTIVE: To elucidate the effects of low-dose arginine vasopressin on cardiopulmonary functions and nitrosative stress using an established model of acute lung injury. DESIGN: Prospective, randomized, controlled laboratory experiment. SETTING: Investigational intensive care unit. SUBJECTS: Eighteen chronically instrumented sheep. INTERVENTIONS: Sheep were randomly assigned to a sham group without injury or treatment, an injury group without treatment (40% total body surface area third-degree burn and 48 breaths of cold cotton smoke), or an injured group treated with arginine vasopressin (0.02 IU·min⁻¹) from 1 hr after injury until the end of the 24-hr study period (each n = 6). All sheep were mechanically ventilated and fluid resuscitated using an established protocol. MEASUREMENTS AND MAIN RESULTS: There were no differences among groups at baseline. The injury was characterized by a severe deterioration of cardiopulmonary function (left ventricular stroke work indexes and Pao2/Fio2 ratio; p < .01 each vs. sham). Compared with controls, arginine vasopressin infusion improved myocardial function, as suggested by higher stroke volume indexes and left ventricular stroke work indexes (18-24 hrs and 6-24 hrs, respectively; p < .05 each). In addition to an improved gas exchange (higher Pao2/Fio2 ratios from 6 to 24 hrs, p < .01 each), pulmonary edema (bloodless wet-to-dry-weight ratio; p = .018), bronchial obstruction (p = .01), and pulmonary shunt fraction (12-24 hrs; p ≤ .001 each) were attenuated in arginine vasopressin-treated animals compared with controls. These changes occurred along with reduced nitrosative stress, as indicated by lower plasma levels of nitrate/nitrite (12-24 hrs, p < .01 each), as well as lower myocardial and pulmonary tissue concentrations of 3-nitrotyrosine (p = .041 and p = .042 vs. controls, respectively). At 24 hrs, pulmonary 3-nitrotyrosine concentrations were negatively correlated with Pao2/Fio2 ratio (r = -.882; p < .001) and myocardial 3-nitrotyrosine content with stroke volume indexes (r = -.701; p = .004). CONCLUSIONS: Low-dose arginine vasopressin reduced nitrosative stress and improved cardiopulmonary functions in sheep with acute lung injury secondary to combined burn and smoke inhalation injury.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Arginina Vasopressina/administração & dosagem , Hemodinâmica/efeitos dos fármacos , Vasoconstritores/administração & dosagem , Lesão Pulmonar Aguda/etiologia , Animais , Débito Cardíaco/efeitos dos fármacos , Pressão Venosa Central/efeitos dos fármacos , Pressão Venosa Central/fisiologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Consumo de Oxigênio/fisiologia , Troca Gasosa Pulmonar , Distribuição Aleatória , Valores de Referência , Ovinos , Carneiro Doméstico , Lesão por Inalação de Fumaça/complicações , Volume Sistólico/efeitos dos fármacos , Tirosina/análogos & derivados , Tirosina/farmacologia , Resistência Vascular/efeitos dos fármacos
6.
Ann Pharmacother ; 44(9): 1471-7, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20716691

RESUMO

The response to treatment was the diagnostic mainstay in ancient times when diseases were poorly understood. Now that the bases of most diseases are known, appropriate diagnostic means are available. However, many physicians still rely on therapeutic tests to establish diagnoses. Since most illnesses are self-limited and because of the placebo effect, many physicians and patients attribute the improvement to the medication and believe that the correct diagnosis was made. However, inappropriate therapeutic tests often lead to diagnostic delays, rapid emergence of antibiotic-resistant bacterial pathogens, increased risks of adverse drug reactions, and unnecessary expenses. To reduce the frequency of unwarranted therapeutic tests, health-care professionals and educators must take steps to rectify the problem.


Assuntos
Diagnóstico , Usos Diagnósticos de Compostos Químicos , Doença , Preparações Farmacêuticas , Ensaios Clínicos como Assunto/história , Custos e Análise de Custo , Resistência a Medicamentos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , História do Século XV , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , História Antiga , História Medieval , Humanos , Efeito Placebo
7.
Crit Care ; 14(4): R129, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20602787

RESUMO

INTRODUCTION: Different isoforms of nitric oxide synthases (NOS) and determinants of oxidative/nitrosative stress play important roles in the pathophysiology of pulmonary dysfunction induced by acute lung injury (ALI) and sepsis. However, the time changes of these pathogenic factors are largely undetermined. METHODS: Twenty-four chronically instrumented sheep were subjected to inhalation of 48 breaths of cotton smoke and instillation of live Pseudomonas aeruginosa into both lungs and were euthanized at 4, 8, 12, 18, and 24 hours post-injury. Additional sheep received sham injury and were euthanized after 24 hrs (control). All animals were mechanically ventilated and fluid resuscitated. Lung tissue was obtained at the respective time points for the measurement of neuronal, endothelial, and inducible NOS (nNOS, eNOS, iNOS) mRNA and their protein expression, calcium-dependent and -independent NOS activity, 3-nitrotyrosine (3-NT), and poly(ADP-ribose) (PAR) protein expression. RESULTS: The injury induced severe pulmonary dysfunction as indicated by a progressive decline in oxygenation index and concomitant increase in pulmonary shunt fraction. These changes were associated with an early and transient increase in eNOS and an early and profound increase in iNOS expression, while expression of nNOS remained unchanged. Both 3-NT, a marker of protein nitration, and PAR, an indicator of DNA damage, increased early but only transiently. CONCLUSIONS: Identification of the time course of the described pathogenetic factors provides important additional information on the pulmonary response to ALI and sepsis in the ovine model. This information may be crucial for future studies, especially when considering the timing of novel treatment strategies including selective inhibition of NOS isoforms, modulation of peroxynitrite, and PARP.


Assuntos
Óxido Nítrico Sintase/metabolismo , Poli Adenosina Difosfato Ribose/metabolismo , Sepse/metabolismo , Tirosina/análogos & derivados , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/fisiopatologia , Animais , Modelos Animais de Doenças , Interleucina-8/análise , Interleucina-8/metabolismo , Interleucina-8/fisiologia , Pulmão/química , Pulmão/enzimologia , Nitratos/sangue , Óxido Nítrico Sintase/fisiologia , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo II/fisiologia , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico Sintase Tipo III/fisiologia , Nitritos/sangue , Poli Adenosina Difosfato Ribose/análise , Poli Adenosina Difosfato Ribose/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sepse/fisiopatologia , Ovinos , Fatores de Tempo , Tirosina/análise , Tirosina/metabolismo , Tirosina/fisiologia
8.
J Med Biogr ; 18(2): 88-98, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20519707

RESUMO

The science of immunology emerged in the last of the 19th and the first of the 20th century. Substantial progress in physics, chemistry and microbiology was essential for its development. Indeed, microorganisms became one of the principal investigative tools of the major founders of that science - Louis Pasteur, Robert Koch, Ilya Ilich Metchnikoff, Paul Ehrlich and Jules Bordet. It is pertinent that these pioneering scientists were born when questioning and exploration were encouraged because of the legacies of the previous century of enlightenment. Mentors greatly aided their development. Their discoveries were shaped by their individual personalities. In turn they developed other contributors to the nascent field. Their discoveries included the types of leukocytes, the roles of neutrophils in inflammation and defence, cellular lysis due to complement, the principles of humoral and cellular immunology, passive and active immunization, tissue antigens, anaphylaxis, anaphylactoid reactions and autoimmunity. Their work formed the basis of modern immunology that developed many decades later. Immunology has enormously impacted our understanding of the pathogenesis, diagnosis and treatment of infections, immune-mediated disorders and inflammation. Burgeoning advances forecast further important clinical applications of immunology. Yet, their applications will be problematic because few physicians sufficiently understand the science. We propose that understanding modern immunology requires a grasp of how that science developed - who made the discoveries, how they were made, their successes and failures, their interactions and debates all reveal the foundation of modern immunology.


Assuntos
Alergia e Imunologia/história , Animais , Pesquisa Biomédica/história , Europa (Continente) , História do Século XIX , História do Século XX , Humanos , Infecções/história , Ciência/história
9.
Am J Physiol Lung Cell Mol Physiol ; 298(3): L427-36, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19965980

RESUMO

Neuronal nitric oxide synthase is critically involved in the pathogenesis of acute lung injury resulting from combined burn and smoke inhalation injury. We hypothesized that 7-nitroindazole, a selective neuronal nitric oxide synthase inhibitor, blocks central molecular mechanisms involved in the pathophysiology of this double-hit insult. Twenty-five adult ewes were surgically prepared and randomly allocated to 1) an uninjured, untreated sham group (n = 7), 2) an injured control group with no treatment (n = 7), 3) an injury group treated with 7-nitroindazole from 1-h postinjury to the remainder of the 24-h study period (n = 7), or 4) a sham-operated group subjected only to 7-nitroindazole to judge the effects in health. The combination injury was associated with twofold increased activity of neuronal nitric oxide synthase and oxidative/nitrosative stress, as indicated by significant increases in plasma nitrate/nitrite concentrations, 3-nitrotyrosine (an indicator of peroxynitrite formation), and malondialdehyde lung tissue content. The presence of systemic inflammation was evidenced by twofold, sixfold, and threefold increases in poly(ADP-ribose) polymerase, IL-8, and myeloperoxidase lung tissue concentrations, respectively (each P < 0.05 vs. sham). These molecular changes were linked to tissue damage, airway obstruction, and pulmonary shunting with deteriorated gas exchange. 7-Nitroindazole blocked, or at least attenuated, all these pathological changes. Our findings suggest 1) that nitric oxide formation derived from increased neuronal nitric oxide synthase activity represents a pivotal reactive agent in the patho-physiology of combined burn and smoke inhalation injury and 2) that selective neuronal nitric oxide synthase inhibition represents a goal-directed approach to attenuate the degree of injury.


Assuntos
Lesão Pulmonar/enzimologia , Óxido Nítrico Sintase Tipo I/antagonistas & inibidores , Obstrução das Vias Respiratórias/complicações , Obstrução das Vias Respiratórias/patologia , Obstrução das Vias Respiratórias/fisiopatologia , Animais , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Ativação Enzimática/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Indazóis/farmacologia , Interleucina-8/metabolismo , Lesão Pulmonar/sangue , Lesão Pulmonar/complicações , Lesão Pulmonar/fisiopatologia , Malondialdeído/metabolismo , Nitratos/sangue , Óxido Nítrico Sintase Tipo I/metabolismo , Nitritos/sangue , Peroxidase/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Pressão , Fluxo Sanguíneo Regional/efeitos dos fármacos , Testes de Função Respiratória , Ovinos , Análise de Sobrevida , Traqueia/irrigação sanguínea , Traqueia/efeitos dos fármacos , Traqueia/enzimologia , Traqueia/patologia , Fator de Transcrição RelA/metabolismo , Tirosina/análogos & derivados , Tirosina/metabolismo
10.
J Med Biogr ; 17(4): 217-24, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20029083

RESUMO

Jules Bordet, a pioneering immunologist, lived until the dawn of molecular immunology. He was born in Belgium in 1870, obtained a medical degree in 1892, worked at l'Institut Pasteur in Paris from 1894 to 1901 and then established the Pasteur Institute of Brabant in Brussels. Before World War I, Bordet found that complement binds to antibody-antigen complexes regardless of the antigen or antibodies involved. Subsequently he developed the complement fixation test that was of diagnostic importance for several decades. For his research concerning complement he was awarded the 1919 Nobel Prize in Physiology or Medicine. During that period he also discovered anaphylatoxin, conglutinin, and the cause of whooping cough (Bordetella pertussis). After World War I he found how thrombin forms, how platelets participate in clotting, lysozyme in human milk and much of the biology of bacteriophages. In addition, Bordet worked fervently to limit weapons of mass destruction and promote peace until his death in 1961.


Assuntos
Alergia e Imunologia/história , Animais , Complexo Antígeno-Anticorpo/história , Distinções e Prêmios , Bacteriófagos , Bélgica , História do Século XIX , História do Século XX , Humanos , Microbiologia/história
11.
12.
Surg Today ; 39(5): 399-406, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19408077

RESUMO

PURPOSE: To evaluate the effects of a monoclonal antibody against interleukin-8 (K2.2) on the microvascular fluid flux after combined injury by burn and smoke inhalation. METHODS: Fourteen sheep were prepared surgically by placing a lung lymph catheter and a flank lymph catheter to examine the microvascular fluid flux. After a recovery period, they were subjected to a combined injury of 40% third-degree burns on the flank and smoke inhalation. RESULTS: This combined injury induced a rapid increase in burned tissue lymph flow (b-Q(L)) and a delayed-onset increase in lung lymph flow (l-Q(L)). The initial increase in b-Q(L) was associated with an elevation of the lymph-to-plasma oncotic pressure ratio, which led to a predominant increase in the burned tissue permeability index (b-PI). Pretreatment with K2.2 had no effect on the permeability change seen in the burned tissue; however, the lung permeability changes were attenuated by pretreatment with K2.2. CONCLUSION: These findings indicate that the pathogenesis of the increase in microvascular fluid flux seen after the combined injury differs in burned tissue and the lung.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Anticorpos Monoclonais/uso terapêutico , Interleucina-8/imunologia , Circulação Pulmonar , Lesão por Inalação de Fumaça/complicações , Lesão Pulmonar Aguda/prevenção & controle , Animais , Queimaduras/complicações , Feminino , Hemodinâmica , Hipóxia , Consumo de Oxigênio , Permeabilidade , Ovinos
13.
Exp Lung Res ; 35(2): 104-18, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19263280

RESUMO

Previous studies have indicated increased plasma levels of inducible nitric oxide synthase in lung. This study further examines the pulmonary expression of nitric oxide synthase (NOS) isoforms in an ovine model of acute lung injury induced by smoke inhalation and burn injury (S+B injury). Female range bred sheep (4 per group) were sacrificed at 4, 8, 12, 24, and 48 hours after injury and immunohistochemistry was performed in tissues for various NOS isoforms. The study indicates that in uninjured sheep lung, endothelial (eNOS) is constitutively expressed in the endothelial cells associated with the airways and parenchyma, and in macrophages. Similarly, neuronal (nNOS) is constitutively present in the mucous cells of the epithelium and in neurons of airway ganglia. In uninjured lung, inducible (iNOS) was present in bronchial secretory cells and macrophages. In tissue after S+B injury, new expression of iNOS was evident in bronchial ciliated cells, basal cells, and mucus gland cells. In the parenchyma, a slight increase in iNOS immunostaining was seen in type I cells at 12 and 24 hours after injury only. Virtually no change in eNOS or nNOS was seen after injury.


Assuntos
Queimaduras/enzimologia , Pulmão/metabolismo , Óxido Nítrico Sintase/análise , Lesão por Inalação de Fumaça/enzimologia , Animais , Brônquios/enzimologia , Epitélio/enzimologia , Feminino , Cinética , Macrófagos/enzimologia , Modelos Animais , Neurônios/enzimologia , Óxido Nítrico Sintase Tipo I/biossíntese , Óxido Nítrico Sintase Tipo II/biossíntese , Óxido Nítrico Sintase Tipo III/biossíntese , Mucosa Respiratória/enzimologia , Ovinos , Distribuição Tecidual
14.
Crit Care Med ; 37(1): 208-14, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19050603

RESUMO

OBJECTIVE: Acute respiratory distress syndrome/acute lung injury is a serious complication of burn patients with concomitant smoke inhalation injury. Nitric oxide has been shown to play a major role in pulmonary dysfunction from thermal damage. In this study, we have tested the hypothesis that inhibition of neuronal nitric oxide synthase could ameliorate the severity of acute lung injury using our well-established ovine model of cutaneous burn and smoke inhalation. DESIGN: Prospective, randomized, controlled, experimental animals study. SETTING: Investigational intensive care unit at university hospital. SUBJECTS: Adult female sheep. INTERVENTIONS: Female sheep (n = 16) were surgically prepared for the study. Seven days after surgery, all sheep were randomly allocated into three study groups: sham (noninjured, nontreated, n = 6); control (injured, treated with saline, n = 6); and neuronal nitric oxide synthase (injured, treated with specific neuronal nitric oxide synthase inhibitor, ZK 234238 (n = 4). Control and neuronal nitric oxide synthase groups were given a cutaneous burn (40% of total body surface, third degree) and insufflated with cotton smoke (48 breaths, <40 degrees C) under halothane anesthesia. Animals in sham group received fake injury also under halothane anesthesia. After injury or fake injury procedure, all sheep were placed on ventilators and resuscitated with lactated Ringer's solution. Neuronal nitric oxide synthase group was administered with continuous infusion of ZK 234238 started 1 hr postinjury with a dose of 100 microg/kg/hr. Sham and control groups received same amount of saline. MEASUREMENTS AND MAIN RESULTS: Cardiopulmonary hemodynamics monitored during the 24-hr experimental time period was stable in the sham group. Control sheep developed multiple signs of acute lung injury. This pathophysiology included decreased pulmonary gas exchange and lung compliance, increased pulmonary edema, and inflammatory indices, such as interleukin-8. Treatment of injured sheep with neuronal nitric oxide synthase inhibitor attenuated all the observed pulmonary pathophysiology. CONCLUSIONS: The results provide definitive evidence that inhibition of neuronal nitric oxide synthase-derived excessive nitric oxide may be a novel and beneficial treatment strategy for pulmonary pathology in burn victims with smoke inhalation injury.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Óxido Nítrico Sintase Tipo I/antagonistas & inibidores , Oxazinas/uso terapêutico , Lesão Pulmonar Aguda/enzimologia , Lesão Pulmonar Aguda/etiologia , Animais , Queimaduras/complicações , Modelos Animais de Doenças , Feminino , Ovinos , Lesão por Inalação de Fumaça/complicações
16.
Free Radic Biol Med ; 45(4): 425-33, 2008 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-18503777

RESUMO

Fire accident victims who sustain both thermal injury to skin and smoke inhalation have gross evidence of systemic and pulmonary oxidant damage and acute lung injury. We hypothesized that gamma-tocopherol (gT), a reactive O(2) and N(2) scavenger, when delivered into the airway, would attenuate lung injury induced by burn and smoke inhalation. Acute lung injury was induced in chronically prepared, anesthetized sheep by 40% total burn surface area, third-degree skin burn and smoke insufflation (48 breaths of cotton smoke, <40 degrees C). The study groups were: (1) Sham (not injured, flaxseed oil (FO)-nebulized, n=6); (2) SA-neb (injured, saline-nebulized, n=6); (3) FO-neb (injured, FO-nebulized, n=6); and (4) gT+FO-neb (injured, gT and FO-nebulized, n=6). Nebulization was started 1 h postinjury, and 24 ml of FO with or without gT (51 mg/ml) was delivered into airways over 47 h using our newly developed lipid aerosolization device (droplet size: 2.5-5 microm). The burn- and smoke inhalation-induced pathological changes seen in the saline group were attenuated by FO nebulization; gT addition further improved pulmonary function. Pulmonary gT delivery along with a FO source may be a novel effective treatment strategy in management of patients with acute lung injury.


Assuntos
Encéfalo/fisiopatologia , Testes de Função Respiratória , Ovinos/fisiologia , Lesão por Inalação de Fumaça/fisiopatologia , gama-Tocoferol/administração & dosagem , Aerossóis , Animais , Encéfalo/enzimologia , Encéfalo/metabolismo , Feminino , Imuno-Histoquímica , Interleucina-6/genética , Interleucina-6/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Malondialdeído/metabolismo , Nebulizadores e Vaporizadores , Poli(ADP-Ribose) Polimerases/metabolismo , RNA Mensageiro/genética , Lesão por Inalação de Fumaça/enzimologia , Lesão por Inalação de Fumaça/metabolismo
17.
J Med Biogr ; 16(2): 96-103, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18463079

RESUMO

Ilya Metchnikoff and Paul Ehrlich shared the 1908 Nobel Prize in Physiology or Medicine - Metchnikoff for discovering the major types and functions of phagocytes and Ehrlich for discovering the types of blood leukocytes, helping to uncover how to generate and use antibodies to protect against bacterial toxins, and formulating the receptor concept of antibodies binding to antigens. In 1908 phagocytic and humoral defences were thought to be unrelated but it was realized much later that they influence one other. Thus, it is fitting that the 1908 Nobel Laureates in Physiology or Medicine remain closely connected in the minds of modern immunologists. Metchnikoff and Ehrlich shared qualities of natural curiosity and tenacity coupled with remarkable inductive-mechanistic thinking and a zest for experimentation. However, their approaches to and methods of research were decidedly different - Metchnikoff's by evolutionary biology and an approach to experimentation via microscopy and Ehrlich's by an imaginative side-chain theory and organic chemistry.


Assuntos
Alergia e Imunologia/história , Prêmio Nobel , Fisiologia/história , História do Século XIX , História do Século XX , Humanos , Macrófagos , Federação Russa , Ucrânia
18.
Crit Care Med ; 36(4): 1196-204, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18379246

RESUMO

OBJECTIVE: We hypothesized that nitric oxide derived from the neuronal nitric oxide synthase (NOS) is responsible for much of the injury resulting from skin burn and smoke inhalation. Therefore, we aimed to examine the effects of selective neuronal NOS inhibition on cardiopulmonary functions and cellular injury in sheep with acute respiratory distress syndrome secondary to combined burn and smoke inhalation injury. DESIGN: Prospective, randomized, controlled laboratory experiment. SETTING: Investigational intensive care unit. SUBJECTS: A total of 22 chronically instrumented adult ewes. INTERVENTIONS: Sheep were randomly assigned to either healthy controls (sham), injured controls (40% third-degree flame burn; 48 breaths of cotton smoke), or an injury group treated with the specific neuronal NOS inhibitor 7-nitroindazole (1 mg x kg(-1) x hr(-1)) from 1 hr postinjury to the end of the 48-hr study period. Hypoxic pulmonary vasoconstriction was assessed as decrease in left pulmonary blood flow in response to single-lung hypoxic challenges (100% nitrogen) at baseline, 24 hrs, and 48 hrs. MEASUREMENTS AND MAIN RESULTS: The combination injury contributed to a approximately 90% loss of hypoxic pulmonary vasoconstriction and was associated with significant pulmonary shunting and death of one animal. The increase in nitrate/nitrite plasma levels in injured controls (12 hrs: 17 +/- 2 vs. 6 +/- 1 microM in sham animals; p < .001) was linked to increases in inducible NOS messenger RNA and 3-nitrotyrosine formation in lung tissue (48 hrs: 22 +/- 1 vs. 0.8 +/- 0.3 nM in sham animals; p < .001). 7-Nitroindazole treatment prevented the injury-associated changes in inducible NOS messenger RNA, nitrate/nitrite, and 3-nitrotyrosine, thereby attenuating the loss of hypoxic pulmonary vasoconstriction and improving gas exchange. In addition, 7-nitroindazole decreased lung tissue concentrations of hemoxygenase-1 and ameliorated myocardial depression, airway obstruction, pulmonary edema, ventilatory pressures, and histopathologic changes seen in injured controls. CONCLUSIONS: The present study provides evidence that neuronal NOS-derived nitric oxide plays a pivotal role in the pathogenesis of acute respiratory distress syndrome resulting from combined burn and smoke inhalation injury.


Assuntos
Queimaduras/complicações , Inibidores Enzimáticos/farmacologia , Indazóis/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Síndrome do Desconforto Respiratório/etiologia , Lesão por Inalação de Fumaça/complicações , Equilíbrio Ácido-Base/efeitos dos fármacos , Animais , Inibidores Enzimáticos/sangue , Feminino , Hemodinâmica/efeitos dos fármacos , Indazóis/sangue , Óxido Nítrico Sintase/sangue , Óxido Nítrico Sintase/fisiologia , Circulação Pulmonar/efeitos dos fármacos , Troca Gasosa Pulmonar/efeitos dos fármacos , Síndrome do Desconforto Respiratório/fisiopatologia , Ovinos
19.
Ann Surg ; 246(3): 512-21; discussion 521-3, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17717455

RESUMO

UNLABELLED: OBJECTIVES AND SUMMARY BACKGROUND: Low tidal volume ventilation (LTV) has improved survival with acute respiratory distress syndrome (ARDS) by reducing lung stretch associated with volutrauma and barotrauma. Additional strategies to reduce lung stretch include arteriovenous carbon dioxide removal (AVCO2R), and high frequency percussive ventilation (HFPV). We performed a prospective, randomized study comparing these techniques in our clinically relevant LD100 sheep model of ARDS to compare survival, pathology, and inflammation between the 3 ventilator methods. METHODS: Adult sheep (n = 61) received smoke inhalation (48 breaths) and a 40% third-degree burn. After ARDS developed (Pao2/FiO2 <200), animals were randomized. In experiment 1, animals were killed at 48 hours after randomization. Hemodynamics, pulmonary function, injury scores, myeloperoxidase (MPO) in lung tissues and neutrophils, IL-8 in lung tissues, and apoptosis were evaluated. In experiment 2, the end point was survival to 72 hours after onset of ARDS or end-of-life criteria with extension of the same studies performed in experiment 1. RESULTS: There were no differences in hemodynamics, but minute ventilation was lower in the AVCO2R group and Paco2 for the HFPV and AVCO2R animals remained lower than LTV. Airway obstruction and injury scores were not different among the 3 ventilation strategies. In experiment 1, lung tissue MPO and IL-8 were not different among the ventilation strategies. However, in experiment 2, lung tissue MPO was significantly lower for AVCO2R-treated animals (AVCO2R < HFPV < LTV). TUNEL staining showed little DNA breakage in neutrophils from experiment 1, but significantly increased breakage in all 3 ventilator strategies in experiment 2. In contrast, AVCO2R tissue neutrophils showed significant apoptosis at 72 hours post-ARDS criteria as measured by nuclear condensation (P < 0.001). Survival 72 hours post-ARDS criteria was highest for AVCO2R (71%) compared with HFPV (55%) and LTV (33%) (AVCO2R vs. LTV, P = 0.05). CONCLUSIONS: Significantly more animals survived AVCO2R than LTV. In experiment 2, Lung MPO was significantly lower for AVCO2R, compared with LTV (P < 0.05). This finding taken together with the TUNEL and neutrophil apoptosis results, suggested that disposition of neutrophils 72 hours post-ARDS criteria was different among the ventilatory strategies with neutrophils from AVCO2R-treated animals removed chiefly through apoptosis, but in the cases of HFPV and LTV, dying by necrosis in lung tissue.


Assuntos
Queimaduras por Inalação/complicações , Dióxido de Carbono/sangue , Respiração Artificial/métodos , Síndrome do Desconforto Respiratório/terapia , Lesão por Inalação de Fumaça/complicações , Análise de Variância , Animais , Apoptose , Modelos Animais de Doenças , Marcação In Situ das Extremidades Cortadas , Interleucina-8/metabolismo , Estudos Prospectivos , Troca Gasosa Pulmonar , Distribuição Aleatória , Síndrome do Desconforto Respiratório/etiologia , Carneiro Doméstico , Taxa de Sobrevida , Volume de Ventilação Pulmonar
20.
J Med Biogr ; 15(2): 104-10, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17551612

RESUMO

When Abraham Lincoln delivered the Gettysburg Address, he was weak and dizzy; his face had a ghastly colour. That evening on the train to Washington, DC, he was febrile and weak, and suffered severe headaches. The symptoms continued; back pains developed. On the fourth day of the illness, a widespread scarlet rash appeared that soon became vesicular. By the tenth day, the lesions itched and peeled. The illness lasted three weeks. The final diagnosis, a touch of varioloid, was an old name for smallpox that was later used in the 20th century to denote mild smallpox in a partially immune individual. It was unclear whether Lincoln had been immunized against smallpox. Indeed, this review suggests that Lincoln had unmodified smallpox and that Lincoln's physicians tried to reassure the public that Lincoln was not seriously ill. Indeed, the successful conclusion of the Civil War and reunification of the country were dependent upon Lincoln's presidency.


Assuntos
Guerra Civil Norte-Americana , Pessoas Famosas , Varíola/história , Fala , História do Século XIX , Humanos , Masculino , Pessoa de Meia-Idade , Pennsylvania , Varíola/virologia
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