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1.
Annu Rev Plant Biol ; 71: 713-739, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32155342

RESUMO

Cannabis sativa L. is an important yet controversial plant with a long history of recreational, medicinal, industrial, and agricultural use, and together with its sister genus Humulus, it represents a group of plants with a myriad of academic, agricultural, pharmaceutical, industrial, and social interests. We have performed a meta-analysis of pooled published genomics data, andwe present a comprehensive literature review on the evolutionary history of Cannabis and Humulus, including medicinal and industrial applications. We demonstrate that current Cannabis genome assemblies are incomplete, with ∼10% missing, 10-25% unmapped, and 45S and 5S ribosomal DNA clusters as well as centromeres/satellite sequences not represented. These assemblies are also ordered at a low resolution, and their consensus quality clouds the accurate annotation of complete, partial, and pseudogenized gene copies. Considering the importance of genomics in the development of any crop, this analysis underlines the need for a coordinated effort to quantify the genetic and biochemical diversity of this species.


Assuntos
Cannabis , Humulus , Cannabis/genética , Família , Genômica
2.
Respir Res ; 20(1): 184, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31416461

RESUMO

BACKGROUND: Influenza attacks the epithelium of the lung, causing cell death and disruption of the epithelial barrier leading to fluid buildup in the lung and impairment of gas exchange. Limited treatment options for severe influenza pneumonia prioritize the need for the discovery of effective therapies. IL-22 is a cytokine that promotes tissue integrity and has strong promise as a treatment option. While research has been focused on the cytokine itself, there is limited understanding of the regulation of the IL-22 receptor (IL-22Ra1) at the epithelial surface during infection. METHODS: IL-22Ra1 levels were measured by qRT-PCR, western blot and immunofluorescence following H1N1 influenza infection (A/PR/8/34 H1N1) or synthetic TLR3 mimetic, Poly (I:C). Regulation of the receptor was determined using STAT inhibitors (STAT1, STAT3 and PanSTAT inhibitors), TLR3 inhibition, and neutralization of interferon alpha receptor 2 (IFNAR2). Significance was determined by a p-value of greater than 0.05. Significance between two groups was measured using unpaired t-test and significance between more than two groups was measured using one-way ANOVA with Tukey Multiple Comparison Test. RESULTS: Here we show both in vivo and in vitro that IL-22Ra1 was induced as early as 24 h after influenza (H1N1 PR8) infection. This induction was triggered by toll-like receptor 3 (TLR3) as a TLR3 mimetic [Poly (I:C)] also induced IL-22Ra1 and inhibition of endosomal formation required for TLR3 function inhibited this process. This upregulation was dependent upon IFNß signaling through STAT1. Importantly, induction of IL-22Ra1 significantly increased IL-22 signaling as evidenced by pSTAT3 levels following IL-22 treatment. CONCLUSION: Collectively, these data suggest epithelial cells may optimize the beneficial effects of IL-22 through the induction of the IL-22 receptor during viral infection in the lung.


Assuntos
Influenza Humana/metabolismo , Receptores de Interleucina/biossíntese , Fator de Transcrição STAT1/biossíntese , Receptor 3 Toll-Like/biossíntese , Células A549 , Animais , Cloroquina/farmacologia , Humanos , Influenza Humana/patologia , Interferons/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Poli I-C/farmacologia
3.
Mucosal Immunol ; 11(1): 199-208, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28401938

RESUMO

Influenza A is a highly contagious respiratory virus that causes seasonal epidemics and occasional worldwide pandemics. The primary cause of influenza-related mortality is bacterial superinfection. There are numerous mechanisms by which preceding influenza infection attenuates host defense, allowing for increased susceptibility to bacterial pneumonia. Herein, we demonstrate that influenza inhibits Staphylococcus aureus-induced production of interleukin-33 (IL-33). Restoration of IL-33 during influenza A and methicillin-resistant S. aureus superinfection enhanced bacterial clearance and improved mortality. Innate lymphoid Type 2 cells and alternatively activated macrophages are not required for IL-33-mediated protection during superinfection. We show that IL-33 treatment resulted in neutrophil recruitment to the lung, associated with improved bacterial clearance. These findings identify a novel role for IL-33 in antibacterial host defense at the mucosal barrier.


Assuntos
Vírus da Influenza A/imunologia , Interleucina-33/metabolismo , Linfócitos/imunologia , Infecções por Orthomyxoviridae/imunologia , Mucosa Respiratória/imunologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/imunologia , Animais , Carga Bacteriana , Imunidade Inata , Interleucina-33/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infiltração de Neutrófilos , Mucosa Respiratória/microbiologia , Mucosa Respiratória/virologia , Superinfecção , Células Th2/imunologia
4.
Mucosal Immunol ; 10(4): 1069-1081, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28247861

RESUMO

Approximately 2 billion people are infected with Mycobacterium tuberculosis (Mtb), resulting in 1.4 million deaths every year. Among Mtb-infected individuals, clinical isolates belonging to the W-Beijing lineage are increasingly prevalent, associated with drug resistance, and cause severe disease immunopathology in animal models. Therefore, it is exceedingly important to identify the immune mechanisms that mediate protection against rapidly emerging Mtb strains, such as W-Beijing lineage. IL-22 is a member of the IL-10 family of cytokines with both protective and pathological functions at mucosal surfaces. Thus far, collective data show that IL-22 deficient mice are not more susceptible to aerosolized infection with less virulent Mtb strains. Thus, in this study we addressed the functional role for the IL-22 pathway in immunity to emerging Mtb isolates, using W-Beijing lineage member, Mtb HN878 as a prototype. We show that Mtb HN878 stimulates IL-22 production in TLR2 dependent manner and IL-22 mediates protective immunity during chronic stages of Mtb HN878 infection in mice. Interestingly, IL-22-dependent pathways in both epithelial cells and macrophages mediate protective mechanisms for Mtb HN878 control. Thus, our results project a new protective role for IL-22 in emerging Mtb infections.


Assuntos
Células Epiteliais/imunologia , Interleucinas/metabolismo , Pulmão/imunologia , Macrófagos/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Animais , Células Cultivadas , Doença Crônica , Resistência a Medicamentos , Humanos , Imunidade nas Mucosas , Interleucinas/genética , Pulmão/microbiologia , Pulmão/patologia , Macaca mulatta , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Interleucina 22
5.
J Vet Pharmacol Ther ; 39(3): 292-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26669905

RESUMO

Respiratory tract infections are common in farmed North American white-tailed deer (Odocoileus virginianus). Tulathromycin is approved for use in cattle but not deer but is often employed to treat deer. The pharmacokinetic properties and lung and muscle concentrations of tulathromycin in white-tailed deer were investigated. Tulathromycin was administered to 10 deer, and then, serum, lung, and muscle tulathromycin concentrations were measured using liquid chromatography-mass spectrometry (LC-MS). The mean maximal serum tulathromycin concentration in deer was 359 ng/mL at 1.3 h postinjection. The mean area under the serum concentration-time curve, apparent volume of distribution, apparent clearance, and half-life was 4883 ng·h/mL, 208 L/kg, 0.5 L/h/kg, and 281 h (11.7 days), respectively. The maximal tulathromycin concentration in lung and muscle homogenate from a single animal was 4657 ng/g (14 days) and 2264 ng/g (7 days), respectively. The minimum concentrations in lung and muscle were 39.4 ng/g (56 days) and 9.1 ng/g (56 days), respectively. Based on similarity in maximal serum concentrations between deer and cattle and high lung concentrations in deer, we suggest the recommended cattle dosage is effective in deer. Tissue concentrations persisted for 56 days, suggesting a need for longer withdrawal times in deer than cattle. Further tissue distribution and depletion studies are necessary to understand tulathromycin persistence in deer tissue; clinical efficacy studies are needed to confirm the appropriate dosage regimen in deer.


Assuntos
Antibacterianos/farmacocinética , Cervos/metabolismo , Dissacarídeos/farmacocinética , Compostos Heterocíclicos/farmacocinética , Pulmão/metabolismo , Músculo Esquelético/metabolismo , Animais , Antibacterianos/química , Antibacterianos/metabolismo , Área Sob a Curva , Dissacarídeos/química , Dissacarídeos/metabolismo , Meia-Vida , Compostos Heterocíclicos/química , Compostos Heterocíclicos/metabolismo , Injeções Subcutâneas/veterinária , Pulmão/química , Estrutura Molecular , Músculo Esquelético/química , Distribuição Tecidual
6.
Am J Transplant ; 16(6): 1766-78, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26693965

RESUMO

Bacterial pneumonia and tracheobronchitis are diagnosed frequently following lung transplantation. The diseases share clinical signs of inflammation and are often difficult to differentiate based on culture results. Microbiome and host immune-response signatures that distinguish between pneumonia and tracheobronchitis are undefined. Using a retrospective study design, we selected 49 bronchoalveolar lavage fluid samples from 16 lung transplant recipients associated with pneumonia (n = 8), tracheobronchitis (n = 12) or colonization without respiratory infection (n = 29). We ensured an even distribution of Pseudomonas aeruginosa or Staphylococcus aureus culture-positive samples across the groups. Bayesian regression analysis identified non-culture-based signatures comprising 16S ribosomal RNA microbiome profiles, cytokine levels and clinical variables that characterized the three diagnoses. Relative to samples associated with colonization, those from pneumonia had significantly lower microbial diversity, decreased levels of several bacterial genera and prominent multifunctional cytokine responses. In contrast, tracheobronchitis was characterized by high microbial diversity and multifunctional cytokine responses that differed from those of pneumonia-colonization comparisons. The dissimilar microbiomes and cytokine responses underlying bacterial pneumonia and tracheobronchitis following lung transplantation suggest that the diseases result from different pathogenic processes. Microbiomes and cytokine responses had complementary features, suggesting that they are closely interconnected in the pathogenesis of both diseases.


Assuntos
Bronquite/diagnóstico , Líquido da Lavagem Broncoalveolar/microbiologia , Citocinas/metabolismo , Transplante de Pulmão/efeitos adversos , Microbiota , Pneumonia Bacteriana/diagnóstico , Traqueíte/diagnóstico , Adulto , Idoso , Teorema de Bayes , Bronquite/etiologia , Bronquite/metabolismo , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Bacteriana/etiologia , Pneumonia Bacteriana/metabolismo , Estudos Retrospectivos , Traqueíte/etiologia , Traqueíte/metabolismo , Transplantados
7.
J Vet Pharmacol Ther ; 38(5): 471-4, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25772094

RESUMO

Tulathromycin is approved for the treatment of respiratory disease in cattle and swine. It is intended for long-acting, single-dose injection therapy (Draxxin), making it particularly desirable for use in bison due to the difficulty in handling and ease of creating stress in these animals. The pharmacokinetic properties of tulathromycin in bison were investigated. Ten wood bison received a single 2.5 mg/kg subcutaneous injection of Draxxin. Serum concentrations were measured by liquid chromatography-mass spectrometry (LC-MS) detection. Tulathromycin demonstrated early maximal serum concentrations, extensive distribution, and slow elimination characteristics. The mean maximum serum concentration (Cmax) was 195 ng/mL at 1.04 h (tmax) postinjection. The mean area under the serum concentration-time curve, extrapolated to infinity (AUC0-inf ), was 9341 ng · h/mL. The mean apparent volume of distribution (Vd /F) and clearance (Cls/F) was 111 L/kg and 0.4 L/h/kg, respectively, and the mean half-life (t1/2) was 214 h (8.9 days). Compared to values for cattle, Cmax and AUC0-inf were lower in bison, while the Vd /F was larger and the t1/2 longer. Tissue distribution and clinical efficacy studies in bison are needed to confirm the purported extensive distribution of tulathromycin into lung tissue and to determine whether a 2.5 mg/kg subcutaneous dosage is adequate for bison.


Assuntos
Antibacterianos/farmacocinética , Bison/metabolismo , Dissacarídeos/farmacocinética , Compostos Heterocíclicos/farmacocinética , Animais , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Bison/sangue , Dissacarídeos/administração & dosagem , Dissacarídeos/sangue , Feminino , Compostos Heterocíclicos/administração & dosagem , Compostos Heterocíclicos/sangue , Injeções Subcutâneas/veterinária
9.
J Vet Pharmacol Ther ; 37(6): 571-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24730377

RESUMO

Antimicrobial efficacy against Lawsonia intracellularis is difficult to evaluate in vitro, thus, the effects of gallium maltolate's (GaM) were investigated in a rabbit model for equine proliferative enteropathy (EPE). Juvenile (5-6-week-old) does were infected with 3.0 × 10(8) L. intracellularis/rabbit and allocated into three groups (n = 8). One week postinfection, one group was treated with GaM, 50 mg/kg; one, with doxycycline, 5 mg/kg; and one with a sham-treatment (control). Feces and blood were collected daily and weekly, respectively, to verify presence of L. intracellularis fecal shedding using qPCR, and seroconversion using immunoperoxidase monolayer assay. Rabbits were sacrificed after 1 week of treatment to collect intestinal tissues focusing on EPE-affected sections. Intestinal lesions were confirmed via immunohistochemistry. No difference was noted between treatments regarding EPE-lesions in jejunum (P = 0.51), ileum (P = 0.74), and cecum (P = 0.35), or in L. intracellularis fecal shedding (P = 0.64). GaM and doxycycline appear to have similar efficacy against EPE in infected rabbits.


Assuntos
Antibacterianos/uso terapêutico , Infecções por Desulfovibrionaceae/veterinária , Lawsonia (Bactéria)/efeitos dos fármacos , Compostos Organometálicos/uso terapêutico , Pironas/uso terapêutico , Animais , Infecções por Desulfovibrionaceae/tratamento farmacológico , Infecções por Desulfovibrionaceae/microbiologia , Infecções por Desulfovibrionaceae/patologia , Modelos Animais de Doenças , Feminino , Coelhos , Resultado do Tratamento
10.
J Vet Pharmacol Ther ; 37(5): 486-99, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24628462

RESUMO

Oral gallium maltolate (GaM) pharmacokinetics (PK) and intestinal tissue (IT) concentrations of elemental gallium ([Ga]) and iron ([Fe]) were investigated in a rabbit model of equine proliferative enteropathy (EPE). New Zealand white does (uninfected controls and EPE-infected, n = 6/group) were given a single oral GaM dose (50 mg/kg). Serial blood samples were collected from 0 to 216 h post-treatment (PT) and IT samples after euthanasia. Serology, qPCR, and immunohistochemistry confirmed, or excluded, EPE. Blood and IT [Ga] and [Fe] were determined using inductively coupled plasma-mass spectrometry. PK parameters were estimated through noncompartmental approaches. For all statistical comparisons on [Ga] and [Fe] α = 5%. The Ga log-linear terminal phase rate constant was lower in EPE rabbits vs. uninfected controls [0.0116 ± 0.004 (SD) vs. 0.0171 ± 0.0028 per hour; P = 0.03]; but half-life (59.4 ± 24.0 vs. 39.4 ± 10.8 h; P = 0.12); Cmax (0.50 ± 0.21 vs. 0.59 ± 0.42 µg/mL; P = 0.45); tmax (1.75 ± 0.41 vs. 0.9 ± 0.37 h; P = 0.20); and oral clearance (6.743 ± 1.887 vs. 7.208 ± 2.565 L/h; P = 0.74) were not. IT's [Ga] and [Fe] were higher (P < 0.0001) in controls. In conclusion, although infection reduces IT [Ga] and [Fe], a 48 h GaM dosing interval is appropriate for multidose studies in EPE rabbits.


Assuntos
Antibacterianos/farmacocinética , Antibacterianos/uso terapêutico , Infecções por Desulfovibrionaceae/microbiologia , Lawsonia (Bactéria) , Compostos Organometálicos/farmacocinética , Compostos Organometálicos/uso terapêutico , Pironas/farmacocinética , Pironas/uso terapêutico , Animais , Infecções por Desulfovibrionaceae/tratamento farmacológico , Feminino , Meia-Vida , Coelhos
11.
Mucosal Immunol ; 7(5): 1186-98, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24549277

RESUMO

Asthma is a common respiratory disease affecting ∼300 million people worldwide. Airway inflammation is thought to contribute to asthma pathogenesis, but the direct relationship between inflammation and airway hyperresponsiveness (AHR) remains unclear. This study investigates the role of inflammation in a steroid-insensitive, severe allergic airway disease model and in severe asthmatics stratified by inflammatory profile. First, we used the T-helper (T(H))-17 cells adoptive transfer mouse model of asthma to induce pulmonary inflammation, which was lessened by tumor necrosis factor (TNF)-α neutralization or neutrophil depletion. Although decreased airspace inflammation following TNFα neutralization and neutrophil depletion rescued lung compliance, neither intervention improved AHR to methacholine, and tissue inflammation remained elevated when compared with control. Further, sputum samples were collected and analyzed from 41 severe asthmatics. In severe asthmatics with elevated levels of sputum neutrophils, but low levels of eosinophils, increased inflammatory markers did not correlate with worsened lung function. This subset of asthmatics also had significantly higher levels of T(H)17-related cytokines in their sputum compared with severe asthmatics with other inflammatory phenotypes. Overall, this work suggests that lung compliance may be linked with cellular inflammation in the airspace, whereas T-cell-driven AHR may be associated with tissue inflammation and other pulmonary factors.


Assuntos
Asma/complicações , Inflamação/complicações , Pulmão/fisiologia , Adolescente , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Animais , Asma/imunologia , Asma/fisiopatologia , Hiper-Reatividade Brônquica/imunologia , Broncoconstritores/farmacologia , Criança , Citocinas/imunologia , Feminino , Humanos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Cloreto de Metacolina/farmacologia , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Escarro/imunologia
13.
Proc Natl Acad Sci U S A ; 108(13): 5308-12, 2011 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-21402916

RESUMO

Conservation scientists, national governments, and international conservation groups seek to devise, and implement, governance strategies that mitigate human impact on the environment. However, few studies to date have systematically investigated the performance of different systems of governance in achieving successful conservation outcomes. Here, we use a newly-developed analytic framework to conduct analyses of a suite of case studies, linking different governance strategies to standardized scores for delivering ecosystem services, achieving sustainable use of natural resources, and conserving biodiversity, at both local and international levels. Our results: (i) confirm the benefits of adaptive management; and (ii) reveal strong associations for the role of leadership. Our work provides a critical step toward implementing empirically justified governance strategies that are capable of improving the management of human-altered environments, with benefits for both biodiversity and people.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/legislação & jurisprudência , Conservação dos Recursos Naturais/métodos , Ecossistema , Governo , Animais , Humanos
14.
Artigo em Inglês | MEDLINE | ID: mdl-22255294

RESUMO

Local volume averaging method and local mass (drug) equilibrium were used for developing a mathematical model for transient drug transport and elimination in the liver. Taking into account the liver porosity and tortuosity, physio-chemical properties of the drug, the drug effective diffusivity, dispersion, convection, local plasma-hepatocyte equilibrium and hepatocellular drug metabolism, the governing partial differential equation was developed and numerically solved to describe a transient drug transfer and elimination across the liver following intravenous (IV) administration. The predicted values of hepatic clearance and bioavailability had very good agreement with the reported observations for different drugs. Unlike the well-stirred, parallel tube and dispersion models of hepatic clearance, the proposed mechanistic model is able to predict the drug concentration gradient across the liver with time and position in very dynamic conditions associated with drug absorption process in the intestine.


Assuntos
Fígado/metabolismo , Farmacocinética , Humanos , Modelos Teóricos
15.
Br J Nutr ; 102(3): 361-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19216812

RESUMO

The present study involved a comparative analysis of the effects of purified flaxseed lignans, secoisolariciresinol diglucoside (SDG) and its aglycone metabolite (SECO), in hyperlipidaemic rats. For hypercholesterolaemia, female Wistars (six rats per group) were fed a standard or 1 % cholesterol diet and orally administered 0, 3 or 6 mg SDG/kg or 0, 1.6 or 3.2 mg SECO/kg body weight once daily for 4 weeks. Hypertriacylglycerolaemia was induced in male Sprague-Dawley rats (ten rats per group) by supplementing tap water with 10 % fructose. These rats were orally administered 0, 3 or 6 mg SDG/kg body weight once daily for 2 weeks. Fasting blood samples (12 h) were collected predose and at the end of the dosing period for serum lipid analyses. Rats were killed and livers rapidly excised and sectioned for lipid, mRNA and histological analyses. Chronic administration of equimolar amounts of SDG and SECO caused similar dose-dependent reductions in rate of body-weight gain and in serum total and LDL-cholesterol levels and hepatic lipid accumulation. SDG and SECO failed to alter hepatic gene expression of commonly reported regulatory targets of lipid homeostasis. SDG had no effect on serum TAG, NEFA, phospholipids and rate of weight gain in 10 % fructose-supplemented rats. In conclusion, our data suggest that the lignan component of flaxseed contributes to the hypocholesterolaemic effects of flaxseed consumption observed in humans. Future studies plan to identify the biochemical mechanism(s) through which flaxseed lignans exert their beneficial effects and the lignan form(s) responsible.


Assuntos
Butileno Glicóis/farmacologia , Linho , Glucosídeos/farmacologia , Hiperlipidemias/dietoterapia , Lignanas/farmacologia , Lipídeos/análise , Fígado/metabolismo , Animais , Sequência de Bases , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Frutose/administração & dosagem , Expressão Gênica , Hiperlipidemias/metabolismo , Hiperlipidemias/patologia , Lipídeos/sangue , Fígado/química , Fígado/patologia , Masculino , Modelos Animais , Dados de Sequência Molecular , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Ratos Wistar
16.
Avian Pathol ; 37(4): 367-73, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18622851

RESUMO

The present study examined the possible role of reactive oxygen species in the pathogenesis of heart failure in broilers. Data were collected from three groups of birds at various risk of heart failure: Leghorn chickens (resistant to heart failure), slow-growing feed-restricted broilers (low risk of heart failure), fast-growing ad libitum fed broilers (high risk of heart failure), and broilers with congestive heart failure (CHF). In the first part of the study, basic clinical parameters and ultrastructural changes were examined in the context of lipid peroxidation of the ventricular myocardium. This was followed by the study of in vitro changes in the activity of selected cytosolic enzymes (creatine kinase and lactate dehydrogenase) and mitochondrial enzymes (pyruvate dehydrogenase and alpha-ketoglutarate dehydrogenase) in the presence of oxidants (hydrogen peroxide or tertiary butyl hydroperoxide). The distinctive clinical feature in the fast-growing broilers and in the broilers with CHF as compared with slow-growing broilers or Leghorn chickens was a significantly lower heart rate (P <0.05). Electron microscopy revealed marked morphological changes in myocardial mitochondria in these broilers (i.e. fast-growing broilers and broilers with CHF). The level of malondialdehyde equivalents, an indicator of lipid peroxidation subsequent to generated oxidative stress, was significantly higher (P <0.05) in ad libitum fed broilers and was highest (P <0.01) in broilers with CHF. In vitro, the presence of oxidants had a detrimental effect on creatine kinase and alpha-ketoglutarate dehydrogenase activity, while lactate dehydrogenase activity increased. The activity of pyruvate dehydrogenase was not altered by oxidants. Our results indicate that the deterioration of heart function in fast-growing commercial broilers in our experimental model is associated with oxidative stress leading to lipid peroxidation of cellular and mitochondrial membranes, and decreased activity of myocardial creatine kinase and alpha-ketoglutarate dehydrogenase enzymes critical for energy synthesis and transformation pathways.


Assuntos
Galinhas/crescimento & desenvolvimento , Galinhas/genética , Predisposição Genética para Doença , Insuficiência Cardíaca/veterinária , Estresse Oxidativo/genética , Doenças das Aves Domésticas/genética , Animais , Privação de Alimentos , Insuficiência Cardíaca/genética , Frequência Cardíaca , Incidência , Miocárdio/enzimologia
17.
Res Vet Sci ; 85(1): 131-40, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17904171

RESUMO

Sudden death syndrome (SDS) in fast growing broiler chickens has been recognized as a patho-physiological entity for four decades, but its pathogenesis still remains unknown. More recent investigations provided evidence that link SDS to cardiac arrhythmia, but the mechanism triggering arrhythmogenesis and factors responsible for fatal outcome are poorly understood. In order to understand the chain of events leading to SDS in broilers, the present study focused on putative mechanisms that trigger arrhythmia and mechanisms that predispose the myocardium to fatal arrhythmia. Susceptibility of broilers to cardiac arrhythmia under stress conditions was evaluated using a simulated stress test with epinephrine. Detailed histopathological evaluation of the broiler heart was undertaken to identify structural features that may predispose the myocardium to fatal arrhythmia. The simulated stress challenge revealed that many broilers are highly susceptible to stress induced cardiac arrhythmia. In some broilers the stress challenge induced severe ventricular arrhythmia, and the life threatening nature of this arrhythmia was evidenced by the fact that several birds showing the most severe arrhythmic responses, died suddenly within several days after the stress challenge. Examination of hearts of broilers that died of SDS revealed microscopic lesions in the cardiomyocytes, and widespread changes in the sub-endocardial and mural His-Purkinje system (HPS). Immune staining for Caspase-3 confirmed that numerous Purkinje cells in the left ventricular myocardium from broiler chickens that died of SDS were undergoing apoptosis. The observed lesions suggest that the electrical stability of the myocardium was compromised. Taken together, our findings indicate that stress is a most likely trigger of cardiac arrhythmia in broilers, whereas the pathological changes seen in the myocardium and in the HPS in fast growing broilers provide a very conducive milieu for sustained ventricular arrhythmia. In cases where the electrical stability of the myocardium is compromised, even an episodic arrhythmic event may readily degenerate to catastrophic ventricular fibrillation and sudden death. We conclude that the combination of stress and changes in the cardiomyocytes and HPS are the key requisite features in the pathogenesis of SDS.


Assuntos
Galinhas , Morte Súbita/veterinária , Doenças das Aves Domésticas/etiologia , Animais , Arritmias Cardíacas/fisiopatologia , Arritmias Cardíacas/veterinária , Morte Súbita/etiologia , Epinefrina/farmacologia , Miocárdio/patologia , Doenças das Aves Domésticas/epidemiologia , Estresse Fisiológico/induzido quimicamente
18.
Tissue Antigens ; 71(2): 178-9, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18069932

RESUMO

We report the novel HLA-Cw allele HLA-Cw*0751. The allele was identified during routine sequence-based typing in our laboratory. The novel allele is identical to Cw*07020101 except for a single nucleotide change in codon 90.2 in position 268. HLA-Cw*0751 allele possesses an adenine at position 268 in exon 2, while HLA-Cw*07020101 has a cytosine at this position. Although this substitution does not change serologic reactivity of HLA-Cw7 molecule, it changes the amino acid at codon 90 from an aspartic acid to an alanine. Aspartic acid is polar and acidic, while alanine is non-polar and neutral.


Assuntos
Antígenos HLA-C/genética , Adenina/química , Alelos , Substituição de Aminoácidos , Citosina/química , Antígenos HLA-C/química , Humanos
19.
Artigo em Inglês | MEDLINE | ID: mdl-17988909

RESUMO

Broiler chickens (Gallus gallus) genetically selected for rapid growth are inherently predisposed to heart failure. In order to understand the biochemical mechanisms associated with the deterioration of heart function and development of congestive heart failure (CHF) in fast-growing chickens, this study examined several factors critical for myocardial energy metabolism. Measured variables included cardiac energy substrates [creatine phosphate (CrP), adenosine triphosphate (ATP), l-carnitine], activity of selected cytosolic enzymes [creatine kinase (CK; EC 2.7.3.2), lactate dehydrogenase (LDH; EC 1.1.1.27)] and mitochondrial enzymes [pyruvate dehydrogenase (PDH; EC 1.2.4.1), alpha-ketoglutarate dehydrogenase (alpha-KGDH; EC 1.2.4.2)]. The CK activities were higher in fast-growing and CHF broilers as compared to slow-growing broilers (p<0.05). Cardiac LDH and alpha-KGDH activities were not changed (p>0.05), whereas PDH activity was highest (p<0.05) in broilers with CHF. Deterioration of heart function is correlated with lowered cardiac ATP, CrP, and l-carnitine levels (all p<0.05). Depletion of high energy phosphate substrates, ATP and CrP, is evident in fast-growing chickens and those that developed CHF. Increased activity of CK suggests that cardiac energy management in fast-growing broilers and those with CHF largely depends on contribution of this pathway to regeneration of ATP from CrP. In this scenario, inadequate level of CrP is a direct cause of ATP insufficiency, whereas low cardiac l-carnitine, because of its role in fatty acid transport, is most likely an important factor contributing to shortage of key substrate required for synthesis of cardiac ATP. The insufficiencies in cardiac energy substrate synthesis provide metabolic basis of myocardial dysfunction in chickens predisposed to heart failure.


Assuntos
Galinhas/crescimento & desenvolvimento , Galinhas/genética , Coração/crescimento & desenvolvimento , Miocárdio/metabolismo , Animais , Dióxido de Carbono/sangue , Galinhas/metabolismo , Genótipo , Coração/fisiologia , Frequência Cardíaca , Masculino , Microscopia Eletrônica de Transmissão , Miocárdio/ultraestrutura , Oxigênio/sangue , Fatores de Tempo
20.
Foot Ankle Int ; 28(5): 584-94, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17559766

RESUMO

BACKGROUND: Reliable measurement of subfascial pressures represents an essential part of compartment syndrome management. To date, there is neither consensus on the number or location of foot compartments, nor a standardized protocol for needle placement. The purpose of this study was to devise a new system using 3-Tesla MRI that assesses the number and location of these compartments. METHODS: To document the specific location of foot compartments, high resolution 3-Tesla MRI (General Electric, Milwaukee, WI) was coupled with a dedicated transmit-receive high signal-to-noise foot/ankle coil (IGC-Medical Advances, Milwaukee, WI). Individual compartments were highlighted and mapped to T1-weighted MRI. Three-dimensional image analysis allowed standardized needle placement recommendations. RESULTS: Six feet from healthy volunteers were imaged. From these, ten compartments were described: (1) medial, (2) central superficial, (3) central deep (adductor), (4) lateral, (5-8) interossei, (9) calcaneal, and (10) skin. Optimal needle placement and depth were identified. CONCLUSIONS: The proposed system allowed us to assess the number and location of foot compartments. Computer image analysis enabled us to define exact points for needle insertion and depth of penetration for accurate pressure monitoring.


Assuntos
Síndromes Compartimentais/diagnóstico , Pé/anatomia & histologia , Imageamento por Ressonância Magnética , Síndromes Compartimentais/fisiopatologia , Feminino , Humanos , Masculino , Modelos Anatômicos , Agulhas , Pressão
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