Circulating endothelial cells are increased in chronic myeloid leukemia blast crisis

We measured circulating endothelial precursor cells (EPCs), activated circulating endothelial cells (aCECs), and mature circulating endothelial cells (mCECs) using four-color multiparametric flow cytometry in the peripheral blood of 84 chronic myeloid leukemia (CML) patients and 65 healthy controls; and vascular endothelial growth factor (VEGF) by quantitative real-time PCR in 50 CML patients and 32 healthy controls. Because of an increase in mCECs, the median percentage of CECs in CML blast crisis (0.0146%) was significantly higher than in healthy subjects (0.0059%, P<0.01) and in the accelerated phase (0.0059%, P=0.01). There were no significant differences in the percentages of CECs in chronic- or active-phase patients and healthy subjects (P>0.05). In addition, VEGF gene expression was significantly higher in all phases of CML: 0.245 in blast crisis, 0.320 in the active phase, and 0.330 in chronic phase patients than it was in healthy subjects (0.145). In conclusion, CML in blast crisis had increased levels of CECs and VEGF gene expression, which may serve as markers of disease progression and may become targets for the management of CML.

Plasmatic ADAMTS-13 metalloprotease and von Willebrand factor in children with cyanotic congenital heart disease

Changes in plasma von Willebrand factor concentration (VWF:Ag) and ADAMTS-13 activity (the metalloprotease that cleaves VWF physiologically) have been reported in several cardiovascular disorders with prognostic implications. We therefore determined the level of these proteins in the plasma of children with cyanotic congenital heart disease (CCHD) undergoing surgical treatment. Forty-eight children were enrolled (age 0.83 to 7.58 years). Measurements were performed at baseline and 48 h after surgery. ELISA, collagen-binding assays and Western blotting were used to estimate antigenic and biological activities, and proteolysis of VWF multimers. Preoperatively, VWF:Ag and ADAMTS-13 activity were decreased (65 and 71% of normal levels considered as 113 (105-129) U/dL and 91 ± 24% respectively, P < 0.003) and correlated (r = 0.39, P = 0.0064). High molecular weight VWF multimers were not related, suggesting an interaction of VWF with cell membranes, followed by proteolytic cleavage. A low preoperative ADAMTS-13 activity, a longer activated partial thromboplastin time and the need for cardiopulmonary bypass correlated with postoperative bleeding (P < 0.05). Postoperatively, ADAMTS-13 activity increased but less extensively than VWF:Ag (respectively, 2.23 and 2.83 times baseline, P < 0.0001), resulting in an increased VWF:Ag/ADAMTS-13 activity ratio (1.20 to 1.54, respectively, pre- and postoperative median values, P = 0.0029). ADAMTS-13 consumption was further confirmed by decreased ADAMTS-13 antigenic concentration (0.91 ± 0.30 to 0.70 ± 0.25 µg/mL, P < 0.0001) and persistent proteolysis of VWF multimers. We conclude that, in pediatric CCHD, changes in circulating ADAMTS-13 suggest enzyme consumption, associated with abnormal structure and function of VWF.

Plasma von Willebrand factor as a predictor of survival in pulmonary arterial hypertension associated with congenital heart disease

Biomarkers have been identified for pulmonary arterial hypertension, but are less well defined for specific etiologies such as congenital heart disease-associated pulmonary arterial hypertension (CHDPAH). We measured plasma levels of eight microvascular dysfunction markers in CHDPAH, and tested for associations with survival. A cohort of 46 inoperable CHDPAH patients (age 15.0 to 60.2 years, median 33.5 years, female:male 29:17) was prospectively followed for 0.7 to 4.0 years (median 3.6 years). Plasma levels of von Willebrand factor antigen (VWF:Ag), tissue plasminogen activator (t-PA) and its inhibitor (PAI-1), P-selectin, reactive C-protein, tumor necrosis factor alpha, and interleukin-6 and -10 were measured at baseline, and at 30, 90, and 180 days in all subjects. Levels of six of the eight proteins were significantly increased in patients versus controls (13 to 106 percent increase, P < 0.003). Interleukin-10 level was 2.06 times normal (P = 0.0003; Th2 cytokine response). Increased levels of four proteins (t-PA, PAI-1, P-selectin, and interleukin-6) correlated with disease severity indices (P < 0.05). Seven patients died during follow-up. An average VWF:Ag (mean of four determinations) above the level corresponding to the 95th percentile of controls (139 U/dL) was independently associated with a high risk of death (hazard ratio = 6.56, 95 percentCI = 1.46 to 29.4, P = 0.014). Thus, in CHDPAH, microvascular dysfunction appears to involve Th2 inflammatory response. Of the biomarkers studied, plasma vWF:Ag was independently associated with survival.

Pattern self-repetition allied to complexity and adaptationof different anatomic structures of human body

The first appliances about Chaos Theory in the biological sciences, made by Robert May, turned visible thegrowth and appliance of this sciences in morphology or even in fisiology, when is stipulated the behaviorof very sensitive systems to different conditions, showing complex behavior. Behind this parameters, itwas stipulated a morphological study in microscopic and macroscopic scales for pathologic appliances andobtaining new parameters in the anatomy and histology field. We observed that the skin shows the greatestself-repetition pattern, being the largest organ in the human body. The circulatory system has its great blooddiffusion in function of a complex branched web of vases in a non-linear shape. It was observed a great fractalpatterns in the structure of the heart, and it’s frequency must be chaotic in function of the need of the humanbody and specific activities to avoid muscular hyperplasia. Bones and articulations denote dynamic interaction,what permit temporal adaptations such as the formation of the cranial bone sutures. The encephalic anatomy,specially the sulcus, got a self-repetition pattern. The following step was to stipulate these concepts in dynamicalprocess such as the cell differentiation.

DNA tests probe the genomic ancestry of Brazilians

We review studies from our laboratories using different molecular tools to characterize the ancestry of Brazilians in reference to their Amerindian, European and African roots. Initially we used uniparental DNA markers to investigate the contribution of distinct Y chromosome and mitochondrial DNA lineages to present-day populations. High levels of genetic admixture and strong directional mating between European males and Amerindian and African females were unraveled. We next analyzed different types of biparental autosomal polymorphisms. Especially useful was a set of 40 insertion-deletion polymorphisms (indels) that when studied worldwide proved exquisitely sensitive in discriminating between Amerindians, Europeans and Sub-Saharan Africans. When applied to the study of Brazilians these markers confirmed extensive genomic admixture, but also demonstrated a strong imprint of the massive European immigration wave in the 19th and 20th centuries. The high individual ancestral variability observed suggests that each Brazilian has a singular proportion of Amerindian, European and African ancestries in his mosaic genome. In Brazil, one cannot predict the color of persons from their genomic ancestry nor the opposite. Brazilians should be assessed on a personal basis, as 190 million human beings, and not as members of color groups.

Hyperhomocystinemia in patients with coronary artery disease

Hyperhomocystinemia has been related to an increased risk of cardiovascular disease in several studies. The C677T polymorphism for the gene that encodes the methylenetetrahydrofolate reductase enzyme (MTHFR) and low plasma folate levels are common causes of hyperhomocystinemia. Due to differences in nutritional patterns and genetic background among different countries, we evaluated the role of hyperhomocystinemia as a coronary artery disease (CAD) risk factor in a Brazilian population. The relation between homocysteine (Hcy) and the extent of CAD, measured by an angiographic score, was determined. A total of 236 patients referred for coronary angiography for clinical reasons were included. CAD was found in 148 (62.7 percent) patients and 88 subjects had normal or near normal arteries. Patients with CAD had higher Hcy levels [mean (SD)] than those without disease (14 (6.8) vs 12.5 (4.0) æM; P = 0.04). Hyperhomocystinemia (Hcy >17.8 æM) prevalence was higher in the CAD group: 31.1 vs 12.2 percent (P = 0.01). After adjustment for major risk factors, we found an independent association between hyperhomocystinemia and CAD (OR = 2.48; 95 percent CI = 1.02-6.14). Patients with a more advanced coronary score had a higher frequency of hyperhomocystinemia and tended to have higher mean Hcy levels. An inverse relation between plasma folate and Hcy levels was found (r = -0.14; P = 0.04). Individuals with the MTHFR C677T polymorphism had a higher prevalence of hyperhomocystinemia than those without the mutated allele. We conclude that hyperhomocystinemia is independently associated with CAD, with a positive association between Hcy level and disease severity.

Ethnicity and glutathione S-transferase (GSTM1/GSTT1) polymorphisms in a Brazilian population

The distribution of polymorphisms related to glutathione S-transferases (GST) has been described in different populations, mainly for white individuals. We evaluated the distribution of GST mu (GSTM1) and theta (GSTT1) genotypes in 594 individuals, by multiplex PCR-based methods, using amplification of the exon 7 of CYP1A1 gene as an internal control. In São Paulo, 233 whites, 87 mulattos, and 137 blacks, all healthy blood-donor volunteers, were tested. In Bahia, where black and mulatto populations are more numerous, 137 subjects were evaluated. The frequency of the GSTM1 null genotype was significantly higher among whites (55.4 percent) than among mulattos (41.4 percent; P = 0.03) and blacks (32.8 percent; P < 0.0001) from São Paulo, or Bahian subjects in general (35.7 percent; P = 0.0003). There was no statistically different distribution among any non-white groups. The distribution of GSTT1 null genotype among groups did not differ significantly. The agreement between self-reported and interviewer classification of skin color in the Bahian group was low. The interviewer classification indicated a gradient of distribution of the GSTM1 null genotype from whites (55.6 percent) to light mulattos (40.4 percent), dark mulattos (32.0 percent) and blacks (28.6 percent). However, any information about race or ethnicity should be considered with caution regarding the bias introduced by different data collection techniques, specially in countries where racial admixture is intense, and ethnic definition boundaries are loose. Because homozygous deletions of GST gene might be associated with cancer risk, a better understanding of chemical metabolizing gene distribution can contribute to risk assessment of humans exposed to environmental carcinogens.

Association of hepatic nuclear factor-4 in the apolipoprotein B promoter: a preliminary report

Previous studies have examined the arrangement of regulatory elements along the apolipoprotein B (apoB) promoter region (-3067 to +940) and a promoter fragment extending from nucleotides -150 to +124 has been demonstrated to be essential for transcriptional activation of the apoB gene in hepatic and intestinal cells. It has also been shown that transcriptional activation of apoB requires a synergistic interaction between hepatic nuclear factor-4 (HNF-4) and CCAAT/enhancer-binding protein a (C/EBPa) transcription factors. Here, we have examined the hypothesis that HNF-4 factor binding to DNA may induce a DNA helix bend, thus facilitating the communication with a C/EBPa factor located one helix turn from this HNF-4 factor in the apoB promoter. A gel electrophoretic mobility shift assay using wild type double-stranded oligonucleotides or modified wild type duplex oligonucleotides with 10 nucleotides inserted between HNF-4 and C/EBPa factor motifs showed similar retarded complexes, indicating that HNF-4 and C/EBPa factors interact independently of the distance between binding sites. However, when only one base, a thymidine, was inserted at the -71 position of the apoB promoter, the complex shift was completely abolished. In conclusion, these results regarding the study of the mechanisms involving the interaction between HNF-4 and C/EBPa factors in the apoB promoter suggest that the perfect 5'-CCCTTTGGA-3' motif is needed in order to facilitate the interaction between the two factors.

Fator von Willebrand e disfunçäo endotelial pulmonar. Implicaçöes prognósticas / von Willebrand factor and pulmonary vascular endothelial cell dysfunction. Prognostic implications

OBJETIVO - Avaliar alteraçöes quantitativas e estruturais do fator von Willebrand (fvW) circulante em 40 pacientes com hipertensäo pulmonar pré-capilar e verificar possíveis implicaçöes prognósticas dos resultados iniciais, em um ano de seguimento. MÉTODOS - A atividade antigênica plasmática do fator von Willebrand (vWF:Ag) foi analisada por imunoeletroforese. A concentraçäo de multímeros de baixo peso molecular em relaçäo...

DNA polymorphisms of apolipoprotein B and AI-CIII-AIV genes in a Brazilian population: a preliminary report

Possible associations between coronary heart disease (CHD) and restriction fragment length polymorphisms (RFLPs) in the apo AI-CIII-AIV cluster and the apo B gene were investigated in a Brazilian population consisting of 46 patients with CHD and 24 individuals without evidence of CHD. A preliminary genetic analysis of SstI RFLP in the apo AI-CIII-AIV cluster showed a significantly higher frequency of the rare SstI allele (S2) in CHD patients as compared with controls. No significant differences were found in the frequencies of PstI RFLP in the apo AI-CIII-AIV cluster or XbaI and EcoRI RFLPs in the apo B gene between CHD patients and controls. Moreover, no association was seen between the RFLPs studied and myocardial infarction or plasma cholesterol or triglyceride levels.

Polymerase chain reaction in the diagnosis of tuberculous meningitis: preliminary report

Nesse relato preliminar säo registrados os resultados da pesquisa de PCR para detecçäo de sequências de DNA (antígeno 65 KDa) do Mycobacteruium tuberculosis no LCR. Foram estudadas amostras de LCR de 20 pacientes: em 10 havia suspeita clínica e laboratorial de neurotuberculose (grupo de teste); nos outros 10 havia suspeita diagnóstica de meningite ou menigoencefalite de outras etiologias ( grupo controle). Em 7 dos 10 pacientes do primeiro grupo a pesquisa de sequências antigênicas de DNA do Mycobacterium tuberculosis por PCR foi positiva; em nenhum dos pacientes do grupo controle a pesquisa foi positiva

Papaverine inhibits human platelet aggregation induced by ADP

The in vitro and ex vivo effect of therapeutic levels of papaverine on human platelet aggregation induced by 3-5 uM adenosine-5-diphosphate (ADP) was evaluated in platelet-rich plasma (PRP) by photometric and impedance aggregometry and in whole blood by impedance aggregometry. Platelet aggregation induced by 3-5 uM ADP in whole blood was significantly inhibited by 5.32 and 10.64 uM papaverine in vitro. This effect was also observed in PRP enriched with erythrocytes but not in PRP alone of enriched with leukocytes. Papaverine (5.32 uM) significantly enhanced the antiplatelet activity of adenosine (0.75 uM) in human whole blood, an effect that was not observed in PRP. A single oral dose of 100 mg papaverine hydrochloride, given to eight healthy human volunteersa 1 h before the platelet aggregation evaluation, significantly inhibited the platelet aggregation induced by 3-5 uM ADP in whole blood. This effect was not observed in PRP. Oral administration of the same dose at 8-h intervals (10 times) to seven additional healthy human volunteers led to a significant negative correlation (r+0.55, P<0.01) between the slope of platelet aggregation in whole blood and plasma papaverine levels )0.12-0.75 uM). Papaverine and adenosine, alone or together, had no in vitro effect on whole blood platelet aggregation of male Wistar rats measured by impedance aggregometry. These results suggest that papaverine inhibits human platelet aggregation in whole blood by an intgeraction with red blood cells

An aqueous extract of guaraná (Paullinia cupana) decreases platelet thromboxane synthesis

The effects of an aqueous extract of guaraná (Paullinia cupana) on rabbit platelet aggregation and thromboxane synthesis were examined. The guaraná extract (100 mg/ml) and fractions separated by TLC (origin and xanthines) decreased platelet aggregation (37.27 and 31% of control values, respectively) and platelet thromboxane formation from [14C]-arachidonic acid (78, 70 and 50% of control values respectively). The decreased thromboxane synthesis could be responsible, at least in part, for the antiaggregatory action of guaraná

A novel property of an aqueous guaraná extract (Paullinia cupana): inhibition of platelet aggregation in vitro and in vivo

Aqueous extracts of guaraná were studied in terms of effects on the aggregation of human and rabbit platelets. Guaraná extracts have anti-aggregatory and de-aggregatory actions on platelet aggragation induced by ADP or arachidonate but not by collagen. The active material was shown to be water soluble and heat resistant and appeared to be different from salicylates, nicotinic acid or known xanthines. Guaraná extracts inhibited platelet aggregation in rabbits following either intravenous or oral administration

Effect of lipid-free milk on prostaglandin synthesis and lipid esterification in the young rabbit aorta

The effect of lipid-free milk on prostaglandin synthesis and lipid esterification by [14C]-aracghidonic acid was examined in one week-old rabbit aortas, ion vitro. In the presence of albumin, lipid-free milk increased arachidonic acid incorporation into aortic phospholipids, cholesterol esters and triglycerides but not into mono-and diglycerides. Lipid-free milk also increased the conversion of arachidonic acid into aortic 6-Keto-PGF1 alfa, but nor into PGF2 alfa or PGE2

Fisiopatologia das cefaleias de origem dietetica. / Fhysiopathology of dietetic headaches

Os fatores dieteticos, que levam ao aparecimento de cefaleias sao analisados. Sao considerados tambem os defeitos bioquimicos que causam deficiencia na metabolizacao e eliminacao de substancias desencandeadoras de cefaleia