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1.
J Exp Med ; 177(6): 1613-21, 1993 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-8496680

RESUMO

Surface immunoglobulin (sIg)-mediated stimulation of B lymphocytes induces a tyrosine kinase-dependent sequence of events leading to rapid and large elevations in intracellular ionized calcium ([Ca2+]i). These early biochemical events do not necessarily lead to proliferation of B cells, however, and conversely, the absence of or inhibition of these events does not necessarily prevent cellular proliferation. We now show by digital image analysis of single B cells that conditions which lead to B cell proliferation are associated with low-level but persistent sustained or cyclic elevations in [Ca2+]i. In marked contrast, early and nonsustained elevations in [Ca2+]i are induced in B cells by stimuli that lead to G1 transition but fail to progress to DNA synthesis. Thus, when B cells were stimulated with mitogenic and nonmitogenic anti-IgD antibodies, both of which induce entry of cells into G1 and early calcium transients of comparable magnitude, persistent low-level calcium elevations were only detected in cells stimulated with the mitogenic antibody. Furthermore, persistent calcium elevations were also seen when B cells were stimulated with a multivalent dextran-anti-Ig conjugate which induced very high levels of B cell proliferation in the absence of detectable phosphatidylinositol 4,5-biphosphate hydrolysis or elevations in [Ca2+]i as detected by flow cytometry. Finally, B cells from X-linked B cell-defective mice, which do not proliferate in response to anti-Ig antibody, show marked and early increases in [Ca2+]i, but do not show persistent calcium elevations. These data suggest that the rapid and large increases of [Ca2+]i seen in lymphocytes within seconds after antigen receptor ligation may be associated with entry in G1, whereas low-level but persistent elevations may be the hallmark of a cell destined to synthesize DNA.


Assuntos
Linfócitos B/metabolismo , Cálcio/metabolismo , DNA/biossíntese , Ativação Linfocitária , Receptores de Antígenos de Linfócitos B/fisiologia , Animais , Anticorpos Anti-Idiotípicos/imunologia , Linfócitos B/imunologia , Camundongos , Camundongos Endogâmicos DBA
2.
Int J Gynecol Cancer ; 19(4): 641-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19509563

RESUMO

Micro-RNAs are a group of small noncoding RNAs approximately 22 nucleotides in length. Recent work has shown differential expression of mature micro-RNAs in human cancers. We characterized the alteration in expression of miR-29b in ovarian serous carcinoma. miR-29b expression was analyzed using quantitative stem-loop reverse transcriptase polymerase chain reaction on a set of 50 formalin-fixed, paraffin-embedded ovarian serous carcinoma samples. Protein expression of p53, estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, Ki-67, and insulinlike growth factor 1 was quantified in the corresponding tissue microarray. The expression profile of miR-29b was correlated with clinicopathological and patient survival data. We provide definitive evidence that miR-29b is down-regulated in a significant proportion of ovarian serous carcinomas and is associated with specific clinicopathological features, most notably high miR-29b expression being associated with reduced disease-free survival.


Assuntos
Cistadenocarcinoma Seroso/genética , MicroRNAs/biossíntese , Neoplasias Ovarianas/genética , Cistadenocarcinoma Seroso/metabolismo , Cistadenocarcinoma Seroso/patologia , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , MicroRNAs/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
3.
Ophthalmologe ; 116(6): 563-568, 2019 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-30051282

RESUMO

BACKGROUND: The World Health Organisation (WHO) defines low vision as a best corrected visual acuity (BCVA) in the better eye between ≥0.5 logMAR and ≤1.3 logMAR. In diabetic macular edema (DME) the correlation between retinal morphology and function is not completely understood in patients with advanced visual impairment. OBJECTIVE: The aim of the study was to describe the pathomorphological similarities of DME in patients with low vision and to correlate them with clinical parameters. MATERIAL AND METHODS: Optical coherence tomography (OCT) and fluorescence angiography (FA) images were graded according to the SAVE protocol and correlated with BCVA, cataract grade and clinical parameters in order to elucidate joint features. RESULTS: Out of a total collective of 65 patients 24 had low vision and 18 of these 24 patients (75%) showed typical signs of atrophic edema according to SAVE protocol criteria (SAVE group 4); however, 6 patients were afflicted with less progressive forms of DME but still suffered from low vision. Common pathomorphological findings were a discontinuity of the ellipsoid zone (EZ; n = 18), loss of pseudosepta (n = 7), layer-disrupting cysts (n = 7) and hard exudates (n = 10). CONCLUSION: It is suggested that a disruption of the EZ, loss of pseudosepta and layer-disrupting cysts are signs of an advanced chronic DME causing low vision. A definition of characteristic pathomorphological patterns of chronic damage in OCT is important for a possible treatment discontinuation in the clinical routine.


Assuntos
Retinopatia Diabética , Edema Macular , Baixa Visão , Humanos , Retina , Tomografia de Coerência Óptica , Acuidade Visual
4.
J Clin Pathol ; 59(7): 721-4, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16556661

RESUMO

AIM: To investigate and compare topoisomerase II-alpha expression in benign prostatic hyperplasia (BPH), prostate cancer of varying Gleason scores and hormone-insensitive prostate cancer. METHODS: The immunohistochemical expression of topoisomerase II-alpha antibody in the above-mentioned diagnostic categories was investigated and compared. RESULTS: Increased expression of topoisomerase II-alpha was seen in the prostate cancers of Gleason scores 7 and 8-10 (p = 0.000) compared with prostate cancers of Gleason score 6 and BPH (p = 0.245). Statistically significant differences were found in the topoisomerase II-alpha gene expression between prostate cancers categorised by Gleason Score. Also, increased expression of topoisomerase II-alpha was seen in the known hormone-resistant prostate carcinomas compared with prostate cancers with no hormone treatment in the subgroup with Gleason scores 8-10, which approached statistical significance (p = 0.081). No statistically significant difference was observed in topoisomerase II-alpha expression between the groups with BPH and prostate carcinoma of Gleason score 6 (p = 0.245). CONCLUSION: Topoisomerase II-alpha expression was found to increase with the known prognostic marker Gleason score and with hormone insensitivity. Objective evidence is provided for clinical trials with drugs targeting topoisomerase II-alpha to be targeted to patients with prostate cancers of Gleason Score >6 and, in particular, prostate cancers of Gleason Scores 8-10.


Assuntos
Adenocarcinoma/enzimologia , Antígenos de Neoplasias/metabolismo , Antineoplásicos Hormonais/uso terapêutico , Biomarcadores Tumorais/metabolismo , DNA Topoisomerases Tipo II/metabolismo , Proteínas de Ligação a DNA/metabolismo , Neoplasias da Próstata/enzimologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Diferenciação Celular , Resistencia a Medicamentos Antineoplásicos , Humanos , Técnicas Imunoenzimáticas , Isoenzimas/metabolismo , Masculino , Hiperplasia Prostática/enzimologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia
5.
Clin Physiol Funct Imaging ; 36(5): 389-95, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26046377

RESUMO

Increased carotid intima-media thickness (cIMT) is associated with an increased risk of cardiac events and stroke. Several semi-automated edge-detection techniques for measuring cIMT are used for research and in clinical practice. Our aim was to compare two currently available semi-automated techniques for the measurement of cIMT. Carotid ultrasound recordings were obtained from 99 subjects (mean age 54·4 ± 8·9 years, range 33-69) without known cardiovascular diseases using a General Electric (GE) Vivid 7 ultrasound scanner, 8-MHz transducer. The far-wall cIMT was evaluated 1-2 cm proximal to the carotid bulb. Three diastolic images (ECG R-wave) from the left and three images from the right common carotid arteries were analysed using GE and Artery Measurement System (AMS) semi-automated softwares. Mean systolic and diastolic blood pressures were 120 ± 13 and 76 ± 8 mmHg, respectively. The cIMTmean (left + right)/2 by GE and cIMTmean (left + right)/2 AMS were highly correlated (r = 0·92, P<0·001). Higher values were measured by GE (0·72 ± 0·12 mm) compared with AMS (0·69 ± 0·12 mm), and this was significant (P<0·001). The coefficients of variation for the intra-observer variability of cIMTmean (left + right)/2 were 1·0% (GE) and 2·2% (AMS). cIMTmean measured by GE's semi-automated edge-detection method correlated well with that measured by AMS. However, there were small but significant systematic differences between the cIMTmean values measured by the two techniques. Thus, the use of only one type of measurement program seems favourable in follow-up studies and when evaluating treatment effects.


Assuntos
Artéria Carótida Primitiva/diagnóstico por imagem , Espessura Intima-Media Carotídea , Interpretação de Imagem Assistida por Computador/métodos , Adulto , Idoso , Automação , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Software
6.
J Neurosci ; 20(3): 1073-84, 2000 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-10648713

RESUMO

Differentiation of progenitors into neurons and glia is regulated by interactions between regulatory DNA elements of neuron- and glia-specific genes and transcription factors that are differentially expressed by progenitors at progressive stages of neural development. We have identified a novel DNA regulatory element (TTTGCAT = septamer) present on the enkephalin (ENK), neuronal cell adhesion molecule, neurofilament of 68 kDa (NF68), growth-associated protein of 43 kDa, glial high-affinity glutamine transporter, tyrosine hydroxylase, etc., genes. When septamer function was blocked by introducing septamer competitor DNA into primary differentiating neural cultures, mRNA levels of ENK, NF68, and glial fibrillary acidic protein decreased by 50-80%, whereas no effect was seen using a control DNA. Septamer elements serve as binding sites for lineage-specific multimeric complexes assembled from three distinct nuclear proteins. Progenitors express a 16 kDa protein (p-sept) which binds to DNA as a homodimer (detected as the 32 kDa P-band). Cells that entered the neuronal lineage express an additional 29 kDa protein (n-sept) that binds to the homodimerized p-sept, and together they form a 62 kDa multimer (detected as N-band). Cells that entered the glial lineage express a distinct 23 kDa protein (g-sept), which along with the homodimerized p-sept form a 56 kDa multimer (observed as G-band). The binding of the distinct protein complexes (P, G, and N) to the septamer site causes a lineage-specific DNA bending (P = 53 degrees; G = 72 degrees; and N = 90 degrees ), which may contribute to the regulatory effect of the septamer interaction. In summary, septamer and its binding proteins represent novel protein-DNA interactions that may contribute to the regulation of neuroglial differentiation in the developing mammalian CNS.


Assuntos
Neuroglia/citologia , Neurônios/citologia , Sequências Reguladoras de Ácido Nucleico/fisiologia , Envelhecimento/metabolismo , Animais , Sequência de Bases/genética , Sítios de Ligação , Encéfalo/embriologia , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Diferenciação Celular/fisiologia , Linhagem Celular , Células Cultivadas , Desenvolvimento Embrionário e Fetal/fisiologia , Dados de Sequência Molecular , Neuroglia/fisiologia , Neurônios/fisiologia , Proteínas Nucleares/metabolismo , Fenótipo , Ratos , Ratos Sprague-Dawley
7.
J Am Coll Cardiol ; 18(4): 1091-7, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1894854

RESUMO

The effects of catheter ablation with radiofrequency versus direct current energy were compared in 18 dogs assigned to two groups (of 9 dogs each). Each dog underwent a single ablation at two sites in the left ventricle at energy levels of 100, 200 or 300 J delivered in unipolar configuration to six dogs each. A transient decrease in left ventricular systolic pressure (from 121.3 +/- 24.5 to 94.2 +/- 18.7 mm Hg, p less than 0.01) and wall motion abnormality were noted in dogs with direct current shock. The left ventricular ejection fraction decreased (from 50 +/- 2% to 34 +/- 3%, p less than 0.001) shortly after direct current ablation but improved 4 weeks later to 43 +/- 3%. There were no significant changes in left ventricular pressure, wall motion or ejection fraction in dogs in the radiofrequency ablation group. Sustained ventricular tachycardia (greater than or equal to 30 s) was seen immediately after direct current shock in all dogs, and one dog died of intractable ventricular fibrillation. A 24-h ambulatory electrocardiographic (ECG) monitor obtained immediately after the procedure showed multiple runs of ventricular tachycardia in all dogs exposed to direct current ablation but in only three dogs that underwent radiofrequency ablation. No differences were found in peak creatine kinase, complete blood count with smear and B-beta 15-42 fibrinopeptide levels. Pathologically, direct current-induced lesions were larger (mean length x width x depth 10.9 x 7.5 x 5.2 vs. 4.8 x 4.6 x 4.3 mm) and were poorly circumscribed with inhomogeneous margins of necrosis.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Arritmias Cardíacas/cirurgia , Eletrocoagulação/métodos , Sistema de Condução Cardíaco/cirurgia , Ondas de Rádio , Animais , Cateterismo Cardíaco , Cães , Eletrocardiografia Ambulatorial , Eletrocoagulação/efeitos adversos , Miocárdio/patologia , Taquicardia/etiologia , Função Ventricular Esquerda/fisiologia
8.
J Clin Pathol ; 58(5): 525-34, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15858126

RESUMO

AIM: To analyse and compare expression patterns of three potential biomarkers-p16(INK4A), CDC6, and MCM5-and evaluate their use as predictive biomarkers in squamous and glandular cervical preinvasive neoplasia. METHODS: Immunocytochemical analysis of p16(INK4A), MCM5, and CDC6 expression was performed on 20 normal, 38 cervical intraepithelial neoplasia 1 (CIN1), 33 CIN2, 46 CIN3, 10 squamous cell carcinoma, 19 cervical glandular intraepithelial neoplasia (cGIN), and 10 adenocarcinoma samples. Staining intensity was assessed using a 0-3 scoring system. p16(INK4A), MCM5, and CDC6 expression was also examined in ThinPrep slides exhibiting mild, moderate, and severe dyskaryosis. Human papillomavirus (HPV) was detected using a modified SYBR green assay. Fluorogenic polymerase chain reaction (PCR) and solution phase PCR were used for specific HPV typing. RESULTS: All three markers showed a linear correlation between expression and grade of dysplasia. p16(INK4A) and MCM5 protein expression was upregulated in all grades of squamous and glandular dysplasia. CDC6 protein was preferentially expressed in high grade lesions and in invasive squamous cell carcinoma. CONCLUSION: p16(INK4A) expression was closely associated with high risk HPV infection-all grades of squamous and glandular cervical lesions were immunohistochemically positive. MCM5 staining intensity was independent of high risk HPV infection, highlighting its potential as a biomarker in both HPV dependent and independent cervical dysplasia. CDC6 may be a biomarker of high grade and invasive lesions of the cervix, with limited use in low grade dysplasia. p16(INK4A) was the most reliable marker of cervical dysplasia. Combinations of dysplastic biomarkers may be useful in difficult diagnostic cases.


Assuntos
Biomarcadores Tumorais/análise , Proteínas de Ciclo Celular/análise , Inibidor p16 de Quinase Dependente de Ciclina/análise , Proteínas de Ligação a DNA/análise , Proteínas Nucleares/análise , Proteínas de Schizosaccharomyces pombe/análise , Displasia do Colo do Útero/química , Neoplasias do Colo do Útero/química , Adenocarcinoma/química , Adenocarcinoma/complicações , Adenocarcinoma/imunologia , Anticorpos Monoclonais/imunologia , Western Blotting/métodos , Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/imunologia , Proteínas de Ciclo Celular/imunologia , Proteínas de Ligação a DNA/imunologia , Feminino , Humanos , Imuno-Histoquímica/métodos , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/imunologia , Proteínas Nucleares/imunologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/diagnóstico , Fatores de Risco , Proteínas de Schizosaccharomyces pombe/imunologia , Neoplasias do Colo do Útero/complicações , Neoplasias do Colo do Útero/imunologia , Displasia do Colo do Útero/complicações , Displasia do Colo do Útero/imunologia
9.
Avian Dis ; 49(3): 390-6, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16252494

RESUMO

Ten conventional and four extensive outdoor broiler flocks, distributed over nine farms, were investigated twice per week during a 35-58-day rearing period to observe the dynamics of Campylobacter spp. spread within these flocks. Strains isolated during this period were genotyped by restriction fragment length polymorphism analysis of the flaA gene and macrorestriction profiling with pulsed field gel electrophoresis. A total of 4112 samples were collected; 157 (3.8%) of these samples were Campylobacter positive, with all C. jejuni. The positive samples were distributed over three conventional and two extensive outdoor flocks on five farms. These five positive flocks were colonized from the fifth to the seventh week of age and remained colonized until slaughter. Each of the flocks showed a flock-specific genotype of Campylobacter that predominated until slaughter. Presuming different ways of entry, a combination of this fact and the observed dynamics of C. jejuni spread within the flocks indicates that a single source from the environment may have been responsible for the colonization of each flock. These conclusions may serve to further develop combat strategies at farm level.


Assuntos
Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/veterinária , Campylobacter/isolamento & purificação , Galinhas/microbiologia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/microbiologia , Animais , Campylobacter/genética , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/transmissão , Flagelina/genética , Genótipo , Abrigo para Animais , Doenças das Aves Domésticas/transmissão , Prevalência , Estações do Ano , Suíça/epidemiologia
11.
Int J Oral Maxillofac Surg ; 44(6): 785-90, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25748609

RESUMO

The objective was to investigate the influence of maxillary alveolar bone on the stress distribution of zygomatic implants in an extra-sinus position. A three-dimensional finite element model was created based on a computed tomography scan of an edentulous female patient. Two zygomatic implants were modelled and placed in the skull in an extra-sinus position. These were supported by the zygomatic bone and the maxillary alveolar bone and were connected by a fixed bridge. This model was duplicated, and the area of the maxillary alveolar bone supporting the implants was removed. Occlusal and lateral forces were applied to both models and the maximum von Mises stresses were recorded. Higher maximum stresses were noted in the model with no alveolar support. Occlusal stresses were higher than lateral stresses in the model with no alveolar support, while occlusal stresses were lower than lateral stresses in the model with alveolar support. Low stresses were noted in the zygomatic bone in both models. Maxillary alveolar bone support is beneficial in the distribution of forces for zygomatic implants placed in an extra-sinus position.


Assuntos
Processo Alveolar/cirurgia , Implantes Dentários , Análise de Elementos Finitos , Maxila/cirurgia , Zigoma/cirurgia , Fenômenos Biomecânicos , Análise do Estresse Dentário , Feminino , Humanos , Imageamento Tridimensional , Arcada Edêntula/cirurgia , Tomografia Computadorizada por Raios X
12.
Ann Anat ; 202: 61-70, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26406882

RESUMO

Dry eye disease, or keratoconjunctivitis sicca, is a multifactorial syndrome with altered tear film homeostasis leading to ocular irritations. These alterations cause discomfort and stress for the patient, but only a few objective parameters allow for proper differential diagnosis into different subtypes of this condition. The mostly invasively performed standard assessment procedures for tear film diagnosis are manifold, but often correlate quite poorly with the subjectively reported symptoms. Due to the inherent limitations, e.g. the subjectivity of the commonly performed invasive tests, a number of devices have been developed to assess the human tear film non-invasively. Since the production, delivery, distribution and drainage of the tear film is a dynamic process, we have focused our review on non-invasive methods which are capable of continuous or repetitive observations of the tear film during an inter-blink interval. These dynamic methods include (1) Interferometry, (2) Pattern Projection, (3) Aberrometry, (4) Thermography; and (5) Evaporimetry. These techniques are discussed with respect to their diagnostic value, both for screening and differential diagnostic of Dry Eye Disease. Many of the parameters obtained from these tests have been shown to have the potential to reliably discriminate patients from healthy subjects, especially when the tests are performed automatically and objectively. The differentiation into subtypes based solely on a single, dynamic parameter may not be feasible, but the combination of non-invasively performed procedures may provide good discrimination results.


Assuntos
Técnicas de Diagnóstico Oftalmológico , Síndromes do Olho Seco/patologia , Lágrimas/química , Lágrimas/citologia , Síndromes do Olho Seco/diagnóstico , Humanos , Interferometria , Ceratoconjuntivite Seca/diagnóstico , Ceratoconjuntivite Seca/patologia , Termografia , Água
13.
Biol Psychiatry ; 15(1): 95-102, 1980 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7357060

RESUMO

Male hooded rats were observed for 6 days following implantation with slow-release subcutaneous pellets containing LSD, mescaline, or control vehicle solution. In animals housed in isolation cages, continuous hallucinogen administration resulted in a gradual increase in head twitches and catatonic postures which peaked 3--4 days after pellet implantation and then declined. In animals housed in social colonies, there were also delayed increases in behavior following hallucinogen-pellet implantation, but these principally involved social behaviors such as fighting by mescaline-treated animals and social grooming by LSD-treated animals. This finding of gradual and cumulative effects of continuous hallucinogen administration contrasts with the usual finding of a rapid tolerance to hallucinogens following repeated injections.


Assuntos
Comportamento Animal/efeitos dos fármacos , Dietilamida do Ácido Lisérgico/farmacologia , Mescalina/farmacologia , Animais , Preparações de Ação Retardada , Tolerância a Medicamentos , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Reflexo de Sobressalto/efeitos dos fármacos , Isolamento Social
14.
Thromb Haemost ; 60(3): 428-33, 1988 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-2976994

RESUMO

In order to define some of the determinants of successful thrombolysis and reocclusion during fibrinolytic therapy for acute myocardial infarction (AMI), specific molecular markers of fibrin metabolism were serially measured in 15 patients with AMI treated with tissue-type plasminogen activator (t-PA). Fibrin formation was assessed by measurement of fibrinopeptide A (FpA) and fibrinolysis by assay of B-beta peptides 1-42 and 15-42 and crosslinked fibrin degradation products (XDP). At baseline, FpA levels were high while markers of fibrinolysis were near normal. Following a 90-minute infusion of t-PA (0.5-1.1 mg kg-1 hr-1), all markers of fibrinolysis increased. Levels of FpA remained elevated despite heparin at the initiation of cardiac catheterization. None of these markers discriminated between patients with successful reperfusion from those without. At 4 hours, B-beta 15-42 peptide and XDP levels remained elevated suggesting persistence of fibrinolysis beyond the short circulatory half-life of t-PA. FpA levels at 4 hours were lower in patients who underwent acute coronary angioplasty compared to those who received additional low dose t-PA (12.3 +/- 4.5 vs. 30.4 +/- 5.5 ng/ml, p less than 0.05). By 48 hours, markers of fibrinolysis had returned toward normal except in 2 patients with persistently elevated B-beta 15-42 peptide levels who suffered reocclusion on days 5 and 6 (75 and 44 vs. 29 +/- 3 nM, p less than 0.005). In conclusion, molecular markers of fibrin metabolism during fibrinolytic therapy may provide clinically relevant data.


Assuntos
Fibrina/metabolismo , Infarto do Miocárdio/metabolismo , Ativador de Plasminogênio Tecidual/uso terapêutico , Angioplastia com Balão , Cateterismo , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Fibrinolisina/metabolismo , Fibrinopeptídeo A/metabolismo , Fibrinopeptídeo B/metabolismo , Humanos , Infarto do Miocárdio/tratamento farmacológico , Fragmentos de Peptídeos/metabolismo , Proteínas Recombinantes/uso terapêutico , Reprodutibilidade dos Testes , Trombina/metabolismo , Fatores de Tempo
15.
Am J Cardiol ; 67(16): 1330-4, 1991 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-2042563

RESUMO

Intracoronary thrombus formation may be involved in the pathogenesis of arterial closure after coronary angioplasty and may contribute to restenosis. It is hypothesized that, unlike markers of platelet activation and fibrin formation, D-dimer, a product of plasmin-mediated proteolysis of cross-linked fibrin, is not subject to significant catheter-induced artifact and could be used to study intracoronary fibrin degradation during angioplasty. No significant difference in D-dimer levels was noted in serial plasma samples obtained from an 8Fr arterial sheath and the wire lumen of an angioplasty balloon catheter, indicating that sampling through the catheter lumen did not induce artifactual D-dimer elevations. Translesion (proximal and distal to the lesion) coronary blood samples were collected in 31 patients undergoing elective coronary angioplasty pretreated with aspirin, dipyridamole and heparin. In 20 of those in whom translesion coronary samples for plasma D-dimer levels (mean +/- standard deviation) were collected before balloon dilation, there was no evidence of ongoing intracoronary fibrinolysis (proximal D-dimer levels, 289 +/- 145 ng/ml; distal, 299 +/- 156 ng/ml; difference not significant). After coronary angioplasty (n = 31), there was a relatively small, but significant (p less than 0.001) increase (45 +/- 71 ng/ml) in translesional D-dimer levels (proximal, 396 +/- 223 ng/ml; distal, 441 +/- 257 ng/ml). The results from this study suggest (1) D-dimer levels are not subject to significant catheter-induced artifact and may be useful for assessment of intracoronary fibrin metabolism, and (2) intracoronary degradation of fibrin can be detected after (but not before) routine coronary angioplasty despite pretreatment with antithrombotic therapy, presumably in response to balloon-induced arterial injury and fibrin formation.


Assuntos
Angioplastia Coronária com Balão/efeitos adversos , Doença das Coronárias/terapia , Trombose Coronária/etiologia , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Idoso , Doença das Coronárias/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Am J Cardiol ; 69(1): 69-76, 1992 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-1729870

RESUMO

There has been increasing application of coronary angioplasty to patients with chronic total occlusions. The acute and long-term outcome in 271 patients after coronary angioplasty (142 single and 129 multiple stenoses) of a total occlusion was compared with 1,429 patients undergoing angioplasty of subtotal (less than or equal to 99% stenosis) occlusions (885 single and 544 multilesion) participating in the 1985-1986 National Heart, Lung, and Blood Institute Percutaneous Transluminal Coronary Angioplasty Registry. Baseline characteristics were similar for each lesion group except for a higher incidence of prior myocardial infarction and left ventricular dysfunction (ejection fraction less than 50%) in patients with total occlusion. Major complications (death, myocardial infarction or emergency bypass surgery) were similar (p = not significant) between patients with total and subtotal occlusions for single (6 vs 7%) and multilesion angioplasty (9 vs 6%). At 2 years, after making adjustments for baseline variables, patients with a total occlusion had a significantly increased risk of death compared with those with subtotal occlusion. There were no significant differences in cumulative event rates for myocardial infarction or bypass surgery. Approximately three-fourths of patients in each group were free of angina at 2 years. In conclusion, angioplasty of chronic total occlusions is associated with a similar acute complication rate. Despite similar relief of anginal symptoms, patients in the total occlusion group have a higher 2-year mortality.


Assuntos
Angioplastia Coronária com Balão , Doença das Coronárias/terapia , Idoso , Angioplastia Coronária com Balão/efeitos adversos , Distribuição de Qui-Quadrado , Ponte de Artéria Coronária , Doença das Coronárias/patologia , Feminino , Oclusão de Enxerto Vascular/terapia , Humanos , Masculino , Pessoa de Meia-Idade , National Institutes of Health (U.S.) , Modelos de Riscos Proporcionais , Sistema de Registros , Resultado do Tratamento , Estados Unidos
17.
Insect Biochem Mol Biol ; 26(5): 511-8, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8763168

RESUMO

Retrotransposable elements encode for several polypeptides that contain a number of conserved amino acid motifs, especially in the region encoding reverse transcriptase. We have used these motifs to design primers for the PCR amplification of retrotransposon DNA. These primers have allowed us to isolate a retroposon, or LINE (long interspersed nuclear element), from the pest insect, Peridroma saucia. DNA sequence analysis of this element, YAKPs1, demonstrated a high degree of homology to a number of retroposons from Drosophila melanogaster, in particular the Fw and Doc elements with homologies of up to 69%. Determination of the complete sequence of the YAKPs1 element will enable a detailed analysis of its evolutionary relatedness to other elements as well as a greater insight into its mode of action.


Assuntos
Mariposas/genética , Retroelementos , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Sequências Repetitivas de Ácido Nucleico , Homologia de Sequência de Aminoácidos
18.
Insect Biochem Mol Biol ; 28(1): 51-8, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9612936

RESUMO

We expressed an N-terminally extended Schistocerca gregaria ion transport peptide (ScgITP) and its homologue (ion transport peptide-like; ITP-L) in insect Sf9 cells using baculovirus expression vectors. Antibodies raised against peptide fragments of ITP and ITP-L were used to detect and characterize the baculovirus expressed peptides (bacITP, bacITP-L). Biological activity of the expressed peptides was assayed using the highly specific bioassay for native ITP, namely the increase in ileal short-circuit current which is a measure of active Cl- transport. BacITP and bacITP-L expression was optimal in Sf9 cells infected at a multiplicity of infection of 1, grown in Grace's medium, and harvested 2-3 days after infection. Western blots showed that bacITP was 2 kDa larger than native or synthetic ITP. This difference was not due to glycosylation and could in part be attributed to post-translational cleavage of the ITP propeptide at a site 11 amino acids upstream of the cleavage site used by S. gregaria to produce native ITP. BacITP stimulated ileal short-circuit current but is significantly less active (270-fold) than synthetic ITP (synITP) possibly as a result of the N-terminal extension. Production of bacITP-L permitted us to show that it is not stimulatory in the bioassay but reduces the synITP response in vitro and thus may have some potential for enhancing the effectiveness of biological control agents such as baculoviruses.


Assuntos
Proteínas de Transporte/genética , Gafanhotos/metabolismo , Hormônios de Inseto/genética , Proteínas de Insetos , Neuropeptídeos/genética , Nucleopoliedrovírus , Sequência de Aminoácidos , Animais , Bioensaio , Western Blotting , Linhagem Celular , Clonagem Molecular , Expressão Gênica , Vetores Genéticos , Gafanhotos/genética , Dados de Sequência Molecular , Processamento de Proteína Pós-Traducional , Spodoptera
19.
Brain Res Mol Brain Res ; 52(1): 98-111, 1997 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9450682

RESUMO

We have developed a novel 'sample and probe' approach as a means to identifying specific DNA elements of the enkephalin gene that control differentiation of the enkephalinergic phenotype during neurodevelopment. The approach is a systematic spatiotemporal analysis of protein-DNA interactions; soluble nuclear proteins ('samples') prepared from microdissected regions of the developing brain are 'probed' with radiolabeled DNA fragments representing various regulatory regions of the enkephalin gene. The resulting spatiotemporal 'molecular maps', i.e. characteristic patterns of protein-DNA complexes showed DNA regions that harbor potential cis-elements regulating differentiation of the enkephalin phenotype at various stages of neurodevelopment. DNase I footprint analysis of such a DNA region identified a binding site (GACGGGAGATCGCTCGT) which is similar to the motif for a lymphoid-specific, developmentally regulated transcription factor, Ikaros, suggesting that the developing brain expresses Ikaros-like transcription factor(s) in a spatiotemporally defined manner. In summary, our approach offers a unique view into the chronology of coordinated protein-DNA interactions and will greatly facilitate identifying DNA elements and isolating development-specific transcription factors.


Assuntos
Encéfalo/embriologia , Encefalinas/genética , Teste de Complementação Genética , Animais , Sequência de Bases , Encéfalo/crescimento & desenvolvimento , Mapeamento Cromossômico , Pegada de DNA , Desoxirribonuclease I , Dados de Sequência Molecular , Fosforilação , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Fatores de Transcrição/metabolismo
20.
Eur J Heart Fail ; 2(2): 151-60, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10856728

RESUMO

BACKGROUND: Doppler tissue imaging (DTI) is an echocardiographic technique by which regional contractility, relaxation properties and time intervals are obtained easily. DTI has been reported to be relatively pre-load independent and could, in comparison with the commonly used mitral pulse wave Doppler (MPWD) method, be of clinical interest for identification of patients with diastolic dysfunction. The atrio-ventricular plane displacement (AVPD) method is an established technique to assess left ventricular systolic function. AIMS: To determine the pulsed Doppler DTI-pattern in patients with heart failure and to examine whether it has a similar capacity as MPWD and AVPD to diagnose diastolic dysfunction. METHODS: We studied 15 controls without congestive heart failure (CHF), 15 patients with diastolic (EF>45%+CHF) and 15 patients with systolic (EF<35%+CHF) left ventricular dysfunction and CHF. RESULTS: The DTI maximal velocities during systole (s), early filling wave (e) and atrial filling wave (a), decrease with reduced left ventricular ejection fraction, r=0.75, r=0.56 and r=0.66 (P<0.001) and regional isovolumetric contraction and intraventricular relaxation time measured by DTI are prolonged, r=0.59 and r=0.73, respectively (P<0.001). The 15 patients with diastolic heart failure were identified by MPWD or DTI but only 11 by AVPD with 8, 10 and 9 false-positive, respectively (P<0.01, P<0.05 and NS). CONCLUSIONS: Regional DTI show a consistent pattern in patients with left ventricular dysfunction and heart failure. Regional DTI has similar accuracy as MPWD in identifying diastolic heart failure patients and is superior to the AVPD technique. DTI may be a useful diagnostic tool in diastolic heart failure patients.


Assuntos
Ecocardiografia Doppler/métodos , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Diástole , Feminino , Humanos , Masculino , Sístole
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