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1.
Haemophilia ; 21(5): e402-10, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26178807

RESUMO

INTRODUCTION: Osteoporosis is common in haemophilic arthropathy. Quantitative ultrasound (QUS) can be a suitable alternative for dual-energy x-ray absorptiometry for diagnosing osteoporosis in haemophiliacs due to its lack of ionizing radiation, and ease to use. AIM: We investigated the intra- and inter-operator reliability of QUS, its responsiveness to bone growth, its ability to differentiate bone adjacent to blood-injected vs. control joints, and the effect of soft tissues on the speed of sound (SOS) QUS values in a juvenile white New Zealand rabbit model of blood-induced arthritis. METHODS: Eight of 16 rabbits were injected with autologous blood (0.1 mL kg(-1) ) 8 times over a 17-week period, the remaining eight rabbits served as controls. SOS was measured at baseline, weeks 8 and 17 in vivo and after the bones were excised on week 17. RESULTS: Intra- and inter-operator coefficients of variation for QUS data were <5% and intraclass correlation coefficients were >60% for 22/27 (81.5%) of bones assessed. The level of interval increase in SOS values from baseline to week 17 was significantly different in tibiae of injected, contralateral to injected and non-injected knee groups by anova (P = 0.01). In vivo (mean ± SD, 4147.17 ± 96.27 m s(-1) ) and postmortem (4457.85 ± 104.00 m s(-1) ) measurements on week 17 differed (P < 0.01) indicating an effect of soft tissues on SOS. CONCLUSION: In conclusion, QUS' acceptable reliability, its responsiveness to growth-related changes and its ability to discriminate injected and non-injected joints make this technique a plausible candidate as a diagnostic tool for osteoporosis in the paediatric haemophilic population if these results are confirmed upon animal-human translation.


Assuntos
Artrite/sangue , Artrite/complicações , Reabsorção Óssea/diagnóstico por imagem , Animais , Autopsia , Reabsorção Óssea/complicações , Modelos Animais de Doenças , Injeções Intra-Articulares , Estudos Longitudinais , Coelhos , Reprodutibilidade dos Testes , Ultrassonografia
4.
Insect Mol Biol ; 22(2): 211-32, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23398403

RESUMO

As important vectors of human disease, phlebotomine sand flies are of global significance to human health, transmitting several emerging and re-emerging infectious diseases. The most devastating of the sand fly transmitted infections are the leishmaniases, causing significant mortality and morbidity in both the Old and New World. Here we present the first global transcriptome analysis of the Old World vector of cutaneous leishmaniasis, Phlebotomus papatasi (Scopoli) and compare this transcriptome to that of the New World vector of visceral leishmaniasis, Lutzomyia longipalpis. A normalized cDNA library was constructed using pooled mRNA from Phlebotomus papatasi larvae, pupae, adult males and females fed sugar, blood, or blood infected with Leishmania major. A total of 47 615 generated sequences was cleaned and assembled into 17 120 unique transcripts. Of the assembled sequences, 50% (8837 sequences) were classified using Gene Ontology (GO) terms. This collection of transcripts is comprehensive, as demonstrated by the high number of different GO categories. An in-depth analysis revealed 245 sequences with putative homology to proteins involved in blood and sugar digestion, immune response and peritrophic matrix formation. Twelve of the novel genes, including one trypsin, two peptidoglycan recognition proteins (PGRP) and nine chymotrypsins, have a higher expression level during larval stages. Two novel chymotrypsins and one novel PGRP are abundantly expressed upon blood feeding. This study will greatly improve the available genomic resources for P. papatasi and will provide essential information for annotation of the full genome.


Assuntos
Perfilação da Expressão Gênica , Proteínas de Insetos/genética , Phlebotomus/genética , Sequência de Aminoácidos , Animais , Sangue/parasitologia , Quimotripsina/genética , Quimotripsina/metabolismo , Etiquetas de Sequências Expressas , Feminino , Biblioteca Gênica , Insetos Vetores/genética , Leishmania major , Masculino , Dados de Sequência Molecular , Filogenia , Polimorfismo de Nucleotídeo Único , Psychodidae/genética , Homologia de Sequência de Aminoácidos , Tripsina/genética , Tripsina/metabolismo
5.
S Afr Med J ; 109(6): 387-391, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31266556

RESUMO

South Africa (SA) is in the process of amending its patent laws. Since its 2011 inception, Fix the Patent Laws, a coalition of 40 patient groups, has advocated for reform of SA's patent laws to improve affordability of medicines in the country. Building on two draft policies (2013, 2017) and a consultative framework (2016) for reform of SA's patent laws, Cabinet approved phase 1 of the Intellectual Property Policy of the Republic of South Africa on 23 May 2018. Fix the Patent Laws welcomed the policy, but highlighted concerns regarding the absence of important technical details, as well as the urgent need for government to develop bills, regulations and guidelines to provide technical detail and to codify and implement patent law reform in the country. In this article, we explore how reforms proposed in SA's new intellectual property policy could improve access to medicine through four medicine case studies.


Assuntos
Custos de Medicamentos , Acessibilidade aos Serviços de Saúde , Patentes como Assunto/legislação & jurisprudência , Preparações Farmacêuticas/economia , Antineoplásicos/economia , Antivirais/economia , Custos e Análise de Custo , Indústria Farmacêutica , Cloridrato de Erlotinib/economia , Guanina/análogos & derivados , Guanina/economia , Humanos , Fatores Imunológicos/economia , Lenalidomida/economia , Sorafenibe/economia , África do Sul
6.
BMC Bioinformatics ; 9: 493, 2008 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-19032776

RESUMO

BACKGROUND: Microarray experimentation requires the application of complex analysis methods as well as the use of non-trivial computer technologies to manage the resultant large data sets. This, together with the proliferation of tools and techniques for microarray data analysis, makes it very challenging for a laboratory scientist to keep up-to-date with the latest developments in this field. Our aim was to develop a distributed e-support system for microarray data analysis and management. RESULTS: EMAAS (Extensible MicroArray Analysis System) is a multi-user rich internet application (RIA) providing simple, robust access to up-to-date resources for microarray data storage and analysis, combined with integrated tools to optimise real time user support and training. The system leverages the power of distributed computing to perform microarray analyses, and provides seamless access to resources located at various remote facilities. The EMAAS framework allows users to import microarray data from several sources to an underlying database, to pre-process, quality assess and analyse the data, to perform functional analyses, and to track data analysis steps, all through a single easy to use web portal. This interface offers distance support to users both in the form of video tutorials and via live screen feeds using the web conferencing tool EVO. A number of analysis packages, including R-Bioconductor and Affymetrix Power Tools have been integrated on the server side and are available programmatically through the Postgres-PLR library or on grid compute clusters. Integrated distributed resources include the functional annotation tool DAVID, GeneCards and the microarray data repositories GEO, CELSIUS and MiMiR. EMAAS currently supports analysis of Affymetrix 3' and Exon expression arrays, and the system is extensible to cater for other microarray and transcriptomic platforms. CONCLUSION: EMAAS enables users to track and perform microarray data management and analysis tasks through a single easy-to-use web application. The system architecture is flexible and scalable to allow new array types, analysis algorithms and tools to be added with relative ease and to cope with large increases in data volume.


Assuntos
Biologia Computacional/métodos , Internet , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Software , Redes de Comunicação de Computadores
7.
BMJ Open ; 6(12): e013361, 2016 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-27927666

RESUMO

INTRODUCTION: Barrett's oesophagus (BO), a metaplastic condition affecting the lower oesophagus due to long-standing gastro-oesophageal reflux and chronic inflammation, is a precursor lesion for oesophageal adenocarcinoma (OADC). There is no clinical test to predict which patients with BO will progress to OADC. The British Society of Gastroenterology recommends endoscopic surveillance of patients with BO. Epigenetic changes have been well characterised in the neoplastic progression of ulcerative colitis to colonic carcinoma, another gastrointestinal cancer associated with chronic inflammation. This systematic review protocol aims to identify and evaluate studies which examine epigenetic biomarkers in BO and their association with progression to OADC. METHODS AND ANALYSIS: All prospective and retrospective primary studies, and existing systematic reviews investigating epigenetic markers including DNA methylation, histone modification, chromatin remodelling, micro and non-coding RNAs of all types will be eligible for inclusion. Eligible patients are those over the age of 18 with BO, BO with dysplasia, OADC or unspecified oesophageal cancer. A comprehensive search of bibliographic databases using combinations of text and index words relating to the population, prognostic markers and outcome will be undertaken with no language restrictions. Results will be screened by 2 independent reviewers and data extracted using a standardised proforma. The quality and risk of bias of individual studies will be assessed using the Quality in Prognostic Studies (QUIPS) tool. A narrative synthesis of all evidence will be performed with key findings tabulated. Meta-analysis will be considered where studies and reported outcomes are considered sufficiently homogeneous, both clinically and methodologically. Findings will be interpreted in the context of the quality of included studies. The systematic review will be reported according to PRISMA guidelines. ETHICS AND DISSEMINATION: This is a systematic review of completed studies and no ethical approval is required. Findings from the full systematic review will be submitted for publication and presentation at national and international conferences which will inform future research on risk stratification in patients with BO. REVIEW REGISTRATION NUMBER: CRD42016038654.


Assuntos
Adenocarcinoma/patologia , Esôfago de Barrett/patologia , Neoplasias Esofágicas/patologia , Lesões Pré-Cancerosas/patologia , Adenocarcinoma/metabolismo , Esôfago de Barrett/complicações , Esôfago de Barrett/metabolismo , Biomarcadores/metabolismo , Progressão da Doença , Endoscopia , Epigenômica , Neoplasias Esofágicas/metabolismo , Refluxo Gastroesofágico , Humanos , Lesões Pré-Cancerosas/complicações , Lesões Pré-Cancerosas/metabolismo , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Revisões Sistemáticas como Assunto
8.
Nat Commun ; 7: 13542, 2016 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-27922008

RESUMO

In spite of extensive recent progress, a comprehensive understanding of how actin cytoskeleton remodelling supports stable junctions remains to be established. Here we design a platform that integrates actin functions with optimized phenotypic clustering and identify new cytoskeletal proteins, their functional hierarchy and pathways that modulate E-cadherin adhesion. Depletion of EEF1A, an actin bundling protein, increases E-cadherin levels at junctions without a corresponding reinforcement of cell-cell contacts. This unexpected result reflects a more dynamic and mobile junctional actin in EEF1A-depleted cells. A partner for EEF1A in cadherin contact maintenance is the formin DIAPH2, which interacts with EEF1A. In contrast, depletion of either the endocytic regulator TRIP10 or the Rho GTPase activator VAV2 reduces E-cadherin levels at junctions. TRIP10 binds to and requires VAV2 function for its junctional localization. Overall, we present new conceptual insights on junction stabilization, which integrate known and novel pathways with impact for epithelial morphogenesis, homeostasis and diseases.


Assuntos
Células Epiteliais/metabolismo , Junções Intercelulares/metabolismo , Automação , Caderinas/metabolismo , Adesão Celular , Humanos , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Especificidade de Órgãos , Fator 1 de Elongação de Peptídeos/metabolismo , Fenótipo , Ligação Proteica , Mapas de Interação de Proteínas , Proteínas Proto-Oncogênicas c-vav/metabolismo , Interferência de RNA , Reprodutibilidade dos Testes
9.
Endocr Relat Cancer ; 12(2): 319-34, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15947106

RESUMO

RET/PTC rearrangements represent key genetic events involved in papillary thyroid carcinoma (PTC) initiation. The aim of the present study was to identify the early changes in gene expression induced by RET/PTC in thyroid cells. For this purpose, microarray analysis was conducted on PCCL3 cells conditionally expressing the RET/PTC3 oncogene. Gene expression profiling 48 h after activation of RET/PTC3 identified a statistically significant modification of expression of 270 genes. Quantitative PCR confirmation of 20 of these demonstrated 90% accuracy of the microarray. Functional clustering of genes with greater than or less than 1.75-fold expression change (86 genes) revealed RET/PTC3-induced regulation of genes with key functions in apoptosis (Ripk3, Tdga), cell-cell signaling (Cdh6, Fn1), cell cycle (Il24), immune and inflammation response (Cxcl10, Scya2, Il6, Gbp2, Oas1, Tap1, RT1Aw2, C2ta, Irf1, Lmp2, Psme2, Prkr), metabolism (Aldob, Ptges, Nd2, Gss, Gstt1), signal transduction (Socs3, Nf1, Jak2, Cpg21, Dusp6, Socs1, Stat1, Stat3, Cish) and transcription (Nr4a1, Junb, Hfh1, Runx1, Foxe1). Genes coding for proteins involved in the immune response and in intracellular signal transduction pathways activated by cytokines and chemokines were strongly represented, indicating a critical role of RET/PTC3 in the early modulation of the immune response.


Assuntos
Carcinoma Papilar/genética , Fatores Imunológicos/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Recombinação Genética , Neoplasias da Glândula Tireoide/genética , Animais , Carcinoma Papilar/imunologia , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Proteínas Proto-Oncogênicas c-ret , Ratos , Neoplasias da Glândula Tireoide/imunologia
10.
J Am Coll Cardiol ; 14(2): 489-95; discussion 496-8, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2754134

RESUMO

Eight dogs were studied by simultaneous invasive hemodynamic and two-dimensional echocardiographic methods to determine whether left ventricular contractility is altered by 2 weeks of rapid atrial pacing. Additionally, this study evaluated the response of three ventricular contractility indexes to both the pacing intervention and acute load alteration. The indexes compared were ejection fraction, peak systolic pressure to end-systolic volume index ratio (SBP/ESVI) and end-systolic wall stress to end-systolic volume index ratio (ESWS/ESVI). After 2 weeks of pacing at 265 +/- 20 min-1 (mean +/- SD), cardiac index and ejection fraction were reduced to 73 +/- 38 ml/kg per min and 22 +/- 6%, respectively, from 161 +/- 22 and 46 +/- 7 before pacing (both p less than 0.001). Concomitantly, SBP/ESVI and ESWS/ESVI were reduced to 34 +/- 10 mm Hg/ml per kg and 54 +/- 19 g/cm2 per ml per kg, respectively, from 84 +/- 29 and 121 +/- 36 before pacing (both p less than 0.005). There were high correlations for the changes in SBP/ESVI and ejection fraction (r = 0.94, p less than 0.001) and ESWS/ESVI and ejection fraction (r = 0.89, p less than 0.003). Acute afterload alteration with phenylephrine depressed ejection fraction but not SBP/ESVI or ESWS/ESVI. Therefore, this study demonstrates 1) that left ventricular contractility is markedly depressed in the dog by 2 weeks of rapid atrial pacing, and 2) that SBP/ESVI and ESWS/ESVI are superior to ejection fraction as ventricular contractility indexes because these ratios accurately measure contractility changes but are influenced less by after-load conditions.


Assuntos
Contração Miocárdica , Marca-Passo Artificial , Volume Sistólico , Animais , Estimulação Cardíaca Artificial , Cães , Ecocardiografia , Átrios do Coração , Masculino , Taquicardia Supraventricular/fisiopatologia , Fatores de Tempo
11.
J Mol Biol ; 264(1): 7-19, 1996 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-8950263

RESUMO

Expression of the aboral ectoderm-specific LpS1 gene in Lytechinus was used to study lineage-specific transcriptional regulation during sea urchin development. Band shift assays using anti-USF antibody showed that a USF-like protein bound the USF core sequence 5'-CACGTG-3' in the promoter of the LpS1 gene. DNA constructs consisting of a wild-type LpS1 promoter and the same LpS1 promoter with a mutated USF binding site fused to the bacterial chloramphenicol acetyltransferase reporter gene were tested. The mutation in the USF binding site caused an increase in chloramphenicol acetyltransferse activity. We selected a clone that encodes USF, LvUSF, from a gastrula-stage cDNA library representing Lytechinus variegatus. Transactivation experiments, in which LvUSF RNA or a DNA construct consisting of the LvUSF cDNA clone fused to the Lytechinus pictus metallothionein promoter coinjected with the wild-type or mutated LpS1 promoter-chloramphenicol acetyltransferase gene construct, showed that chloramphenicol acetyltransferase activity from the wild-type construct was repressed, while the construct mutated at the USF binding site was active. The same wild-type and mutated LpS1 promoter DNA fragments ligated to the green fluorescent protein reporter gene were used to examine spatial expression. The reporter gene constructs containing the mutated USF binding site were expressed inappropriately in all cell types including the gut and oral ectoderm in gastrula and larva stage embryos, while the wild-type constructs were expressed primarily in the aboral ectoderm. USF was expressed in all cells of the early embryo and in all tissues except the aboral ectoderm in later embryos. The data are consistent with a model depicting Lytechinus USF, as a temporal and spatial regulator by repressing LpS1 gene transcription in non-aboral ectoderm cells.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação a DNA , Proteínas Repressoras/genética , Ouriços-do-Mar/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação/genética , Cloranfenicol O-Acetiltransferase/genética , Cloranfenicol O-Acetiltransferase/metabolismo , Clonagem Molecular , DNA Complementar/genética , Embrião não Mamífero/citologia , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Dados de Sequência Molecular , Regiões Promotoras Genéticas , RNA/genética , RNA/metabolismo , Proteínas Repressoras/metabolismo , Ouriços-do-Mar/crescimento & desenvolvimento , Ouriços-do-Mar/metabolismo , Fatores de Transcrição/metabolismo , Fatores Estimuladores Upstream
12.
Mech Dev ; 44(1): 33-40, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8155573

RESUMO

Development and LpS1 transcription in Lytechinus embryos are arrested at the mesenchyme blastula stage when collagen deposition is inhibited by the lathrytic agent beta-aminopropionitrile (BAPN) or by proline analogs. We found that human recombinant platelet derived growth factor-BB (PDGF-BB) and transforming growth factor-alpha (TGF-alpha) synergistically rescue collagen disrupted/developmentally arrested L. pictus and L. variegatus embryos so that development and RNA accumulation of LpS1 proceed. In addition, nonspecific antagonists of PDGF block gastrulation and LpS1 RNA accumulation. The embryos recover and LpS1 RNA accumulation resumes when the antagonists are removed. These data suggest that a growth factor mediated pathway, associated with the ECM, is required for sea urchin gastrulation, spiculogenesis, and LpS1 gene activation.


Assuntos
Colágeno/farmacologia , Gástrula/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/farmacologia , Ouriços-do-Mar/efeitos dos fármacos , Fator de Crescimento Transformador alfa/farmacologia , Animais , Becaplermina , Sinergismo Farmacológico , Expressão Gênica/efeitos dos fármacos , Substâncias de Crescimento/farmacologia , Proteínas Proto-Oncogênicas c-sis , Proteínas Recombinantes/farmacologia , Ouriços-do-Mar/embriologia
13.
Arch Dis Child Fetal Neonatal Ed ; 90(4): F341-2, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16036894

RESUMO

There is a need to explore novel methods of assessing bone health in sick preterm infants. This study of the speed of sound in the long bones of newborn term and preterm infants shows that, in this population, this technique is not site specific and has a high degree of interobserver and intraobserver precision. The speed of sound in newborn infants is primarily dependent on gestation rather than birth weight.


Assuntos
Doenças Ósseas/diagnóstico por imagem , Doenças do Prematuro/diagnóstico por imagem , Peso ao Nascer , Osso e Ossos/diagnóstico por imagem , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , Masculino , Variações Dependentes do Observador , Rádio (Anatomia)/diagnóstico por imagem , Reprodutibilidade dos Testes , Tíbia/diagnóstico por imagem , Ultrassonografia
14.
Gene ; 147(2): 219-22, 1994 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-7926803

RESUMO

Homeobox genes from the urochordates Styela clava (AHox2) and S. plicata (AHox3) were cloned and analyzed. The two genes are homologous and Antennapedia-like. The homeobox regions have 87% identity at the nucleotide level and are identical at the amino-acid level. No introns are present in the homeobox region of AHox3, and AHox3 is represented at a low copy number per haploid genome. AHox2 and AHox3 represent the second type of homeobox gene found in this evolutionarily and developmentally important group of organisms.


Assuntos
Genes Homeobox , Urocordados/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos
15.
Virus Res ; 53(2): 151-62, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9620207

RESUMO

Canine herpesvirus (CHV) is an alpha-herpesvirus of limited pathogenicity in healthy adult dogs and infectivity of the virus appears to be largely limited to cells of canine origin. CHV's low virulence and species specificity make it an attractive candidate for a recombinant vaccine vector to protect dogs against a variety of pathogens. As part of the analysis of the CHV genome, the authors determined the complete nucleotide sequence of the CHV US region as well as portions of the flanking inverted repeats. Seven full open reading frames (ORFs) encoding proteins larger than 100 amino acids were identified within, or partially within the CHV US: cUS2, cUS3, cUS4, cUS6, cUS7, cUS8 and cUS9; which are homologs of the herpes simplex virus type-1 US2; protein kinase; gG, gD, gI, gE; and US9 genes, respectively. An eighth ORF was identified in the inverted repeat region, cIR6, a homolog of the equine herpesvirus type-1 IR6 gene. The authors identified and mapped most of the major transcripts for the predicted CHV US ORFs by Northern analysis.


Assuntos
Genoma Viral , Herpesvirus Canídeo 1/genética , Animais , Linhagem Celular , Clonagem Molecular , Cães , RNA Viral
16.
Am J Cardiol ; 37(3): 373-81, 1976 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-1258770

RESUMO

The status of myocardial function in rabbits subjected to cardiac catheterization and infection with Streptococcus viridans was assessed at 3 and 6 days. Sham-operated control animals as well as uninfected catheterized animals were used for comparison. Although left heart hypertrophy and interstitial edema were evident in both uninfected and infected animals, the infected animals exhibited in addition mononuclear cell infiltration and muscle degeneration as well as lung congestion and accumulation of pleural fluid. Both uninfected and infected animals has elevated levels of serum creatine phosphokinase, lactic dehydrogenase and glutamic oxaloacetic transaminase as well as electrocardiographic abnormalities such as increased amplitude of the ORS complex and flattening or inversion of the T wave. Unlike findings in the uninfected animals, the serum calcium, magnesium and sodium levels were slightly but significantly decreased and serum potassium levels were increased in the infected rabbits. Both heart rate and pulse pressure were higher in 6 day uninfected and 3 day infected animals whereas 6 day infected animals showed a decrease in heart rate. In comparison to the sham-operated control rabbits and the uninfected animals, the infected animals exhibited depression in the rates of left ventricular pressure development and relaxation as well as prolongation in time for half relaxation in situ. Relative maximal contractile element velocity extrapolated from intraventricular pressure-velocity curves was decreased by 24, 52 and 76 percent, respectively, of control values in the uninfected hearts and those with 3 and 6 days of infection. The isolated perfused hearts from infected animals also generated less contractile force and showed a decrease in the rates of contraction and relaxation, but half-relaxation time was increased. These results demonstrate myocardial dysfunction during experimental bacterial endocarditis and provide evidence that infective cardiomyopathy is associated with heart failure.


Assuntos
Fosfatase Alcalina/sangue , Animais , Aspartato Aminotransferases/sangue , Creatina Quinase/sangue , Modelos Animais de Doenças , Insuficiência Cardíaca/etiologia , L-Lactato Desidrogenase/sangue , Masculino , Miocárdio/patologia , Coelhos , Infecções Estreptocócicas/enzimologia , Infecções Estreptocócicas/patologia , Infecções Estreptocócicas/fisiopatologia
17.
Biochem Pharmacol ; 34(22): 4033-41, 1985 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-2998397

RESUMO

The present study has examined early cellular effects of chronic adriamycin administration to dogs using a protocol (1 mg/kg/week to a total cumulative dose of 240 mg/m2) producing significant but small reductions in ejection fraction and stroke volume as determined echocardiographically prior to the development of clinical or radiological manifestations of heart failure. At this early phase of cardiomyopathy, significant reduction (P less than 0.05) in sarcoplasmic reticulum Ca2+, K+-ATPase was observed without any change in mitochondrial, lysosomal or sarcolemmal marker enzymes. Myocardial calcium (P less than 0.01) and glutathione (P less than 0.001) levels were increased significantly. Detailed analysis of myocardial phospholipid profiles failed to show any significant differences between control and treated dogs. In contrast, red cell membranes showed increased phosphatidylcholine (PC) and decreased phosphatidylserine (PS) contents, resulting in a significant increase in PC/PS ratio (P less than 0.05). No significant changes were detected in activities of catalase, superoxide dismutase or glutathione peroxidase in erythrocytes or myocardial tissue from control and adriamycin-treated animals. A significant (P less than 0.05) elevation in plasma sialic acid was observed following adriamycin treatment. Our results suggest that early adriamycin-induced damage is unlikely to result from alterations in cellular processes protecting tissues against oxidant injury. Regression analysis indicated that, of the various abnormalities observed, only the elevated myocardial calcium levels and the increases in plasma sialic acid correlated with the degree of myocardial functional impairment. Our findings suggest the presence of sarcolemmal alterations in Ca2+ handling in early adriamycin-induced myocardial injury and indicate that measurement of plasma sialic acid should be further investigated as a possible noninvasive indicator of impending adriamycin cardiotoxicity.


Assuntos
Cardiomiopatias/induzido quimicamente , Doxorrubicina/toxicidade , Coração/fisiopatologia , Animais , ATPases Transportadoras de Cálcio/análise , Cardiomiopatias/patologia , Cardiomiopatias/fisiopatologia , Modelos Animais de Doenças , Cães , Ecocardiografia , Complexo IV da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Radicais Livres , Glutationa/análise , Miocárdio/análise , Fosfolipídeos/análise
18.
J Heart Lung Transplant ; 10(4): 518-26, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1911794

RESUMO

Preservation of the donor heart is an important and controversial subject in heart transplantation. This study compares simple hypothermic storage and hypothermic perfusion in a swine model of heart transplantation (n = 14). The donor hearts of group A (n = 7) were placed in simple hypothermic storage for 5 hours. The donor hearts of group B (n = 7) were placed onto a perfusion apparatus for 5 hours, with pressure maintained at 28 cm of H2O and a myocardial temperature of 8 to 10 degrees C. In both groups the hearts were initially protected with isosmolar potassium cardioplegic solution. The perfusate in group B contained moderate sodium, mannitol, glucose, insulin, and oxygen. The ischemic interval within both groups was 6 hours including orthotopic transplantation. Investigation was conducted at three time periods: prepreservation, postpreservation, and immediately after loading. For both groups there was nonsignificant depression of myocardial function (cardiac index, stroke index, stroke work index, ejection fraction, and wall stress) at the postpreservation period. After volume loading, for the hypothermic perfusion group there was significant improvement of myocardial function (cardiac index, p less than 0.01; stroke index, p less than 0.01) with no significant change in heart rate, systemic vascular resistance, and systolic blood pressure. There was also significant improvement in myocardial performance (p less than 0.05) for the hypothermic perfusion group after volume loading. Ultrastructural changes were minimal for both groups, and there were no major heart transplantation after 6 hours of ischemia; however, hearts retain their contractile capacity better after hypothermic perfusion than after simple hypothermic storage.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Soluções Cardioplégicas , Temperatura Baixa , Transplante de Coração , Preservação de Órgãos/métodos , Animais , Ecocardiografia , Transplante de Coração/fisiologia , Microscopia Eletrônica , Miocárdio/química , Miocárdio/ultraestrutura , Perfusão , Suínos , Fatores de Tempo
19.
DNA Cell Biol ; 15(6): 511-7, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8672248

RESUMO

LpS1 RNA transcripts and proteins are expressed exclusively in the aboral ectoderm of the embryo in the sea urchin Lytechinus pictus. We have characterized the LpS1-beta promoter to identify the cis-acting elements that may be involved in the aboral ectoderm-specific expression of the LpS1-beta gene. The distal G-string site, composed of six contiguous guanine deoxynucleotides located at -721 to -726, was analyzed. A mutation at the distal G-string caused over a two-fold increase in reporter chloramphenicol acetyltransferase gene activity and inappropriate expression of reporter green fluorescent protein in nonaboral ectoderm cells in L. pictus embryos. These results suggest that the proteins that bind the distal G-string act as a spatial repressor in the nonaboral ectoderm cells of the developing embryo.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Regiões Promotoras Genéticas/genética , Proteínas Repressoras/metabolismo , Ouriços-do-Mar/genética , Fatores de Transcrição/genética , Animais , Sequência de Bases , Sítios de Ligação , Cloranfenicol O-Acetiltransferase/biossíntese , Cloranfenicol O-Acetiltransferase/genética , DNA/metabolismo , DNA Recombinante , Ectoderma , Embrião não Mamífero , Genes Reporter/genética , Proteínas de Fluorescência Verde , Proteínas Luminescentes/biossíntese , Proteínas Luminescentes/genética , Dados de Sequência Molecular , Mutação , Ouriços-do-Mar/embriologia
20.
Neurochem Int ; 45(5): 669-76, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15234109

RESUMO

Alpha synuclein protein may play an important role in familial and sporadic Parkinson's disease pathology. We have induced G209A mutant or wild-type alpha-synuclein expression in stable HEK293 cell models to determine if this influences markers of oxidative stress and damage under normal conditions or in the presence of dopamine or paraquat. Induced wild-type or mutant alpha-synuclein expression alone had no effect upon levels of oxidative stress or damage, as measured by glutathione levels or aconitase activity. Both wild-type and mutant alpha-synuclein expression decreased the oxidative damage induced by paraquat, although the protection was less marked with mutant alpha-synuclein expression. This suggests that alpha-synuclein expression may either have anti-oxidant properties or may upregulate cellular antioxidant levels, a function that was diminished by the G209A mutation. However, mutant but not wild-type alpha-synuclein expression specifically enhanced dopamine associated oxidative damage. Non-expressing cells treated with reserpine to inhibit the vesicular monoamine compartmentalisation produced similar results. However, consistent with the hypothesis that mutant alpha-synuclein disrupts vesicular dopamine compartmentalization, this effect was diminished in cells expressing mutant alpha-synuclein. This may result in increased dopamine metabolism and cause selective oxidative damage to dopaminergic cells.


Assuntos
Dopamina/toxicidade , Ecdisterona/análogos & derivados , Mutação/genética , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Aconitato Hidratase/metabolismo , Inibidores da Captação Adrenérgica/farmacologia , Western Blotting , Linhagem Celular , Células Cultivadas , Dopamina/metabolismo , Ecdisterona/farmacologia , Glutationa/análise , Glutationa/metabolismo , Herbicidas/toxicidade , Humanos , Imuno-Histoquímica , Paraquat/toxicidade , Reserpina/farmacologia , Sinucleínas , alfa-Sinucleína
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