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1.  The I405V and Taq1B polymorphisms of the CETP gene differentially affect sub-clinical carotid atherosclerosis 
Background
Cholesteryl ester transfer protein (CETP) plays a major role in lipid metabolism, but studies on the association of CETP polymorphisms with risks of cardiovascular disease are inconsistent. This study investigated whether the CETP gene I405V and Taq1B polymorphisms modified subclinical atherosclerosis in an asymptomatic Brazilian population sample.
Methods
The polymorphisms were analyzed using polymerase chain reaction in 207 adult volunteers. Serum lipid profiles, oxLDL Ab titers, C-reactive protein and tumor necrosis factor-α concentrations and CETP and phospholipid transfer protein (PLTP) activities were determined, and common carotid artery intima-media thickness (cIMT) was measured using ultrasonography.
Results
No differences in cIMT were observed between the presence or absence of the minor B2 and V alleles in either polymorphism. However, inverse correlations between mean cIMT and CETP activity in the presence of these polymorphisms were observed, and positive correlations of these polymorphisms with PLTP activity and oxLDL Ab titers were identified. Moreover, logistic multivariate analysis revealed that the presence of the B2 allele was associated with a 5.1-fold (CI 95%, OR: 1.26 – 21.06) increased risk for cIMT, which was equal and above the 66th percentile and positively interacted with age. However, no associations with the V allele or CETP and PLTP activities were observed.
Conclusions
None of the studied parameters, including CETP activity, explained the different relationships between these polymorphisms and cIMT, suggesting that other non-determined factors were affected by the genotypes and related to carotid atherosclerotic disease.
doi:10.1186/1476-511X-11-130
PMCID: PMC3503625  PMID: 23039379
Carotid atherosclerosis; Carotid intima-media thickness; Cholesteryl ester transfer protein; Genetic polymorphism
2.  High resolution melting: improvements in the genetic diagnosis of hypertrophic cardiomyopathy in a Portuguese cohort 
BMC Medical Genetics  2012;13:17.
Background
Hypertrophic Cardiomyopathy (HCM) is a complex myocardial disorder with a recognized genetic heterogeneity. The elevated number of genes and mutations involved in HCM limits a gene-based diagnosis that should be considered of most importance for basic research and clinical medicine.
Methodology
In this report, we evaluated High Resolution Melting (HRM) robustness, regarding HCM genetic testing, by means of analyzing 28 HCM-associated genes, including the most frequent 4 HCM-associated sarcomere genes, as well as 24 genes with lower reported HCM-phenotype association. We analyzed 80 Portuguese individuals with clinical phenotype of HCM allowing simultaneously a better characterization of this disease in the Portuguese population.
Results
HRM technology allowed us to identify 60 mutated alleles in 72 HCM patients: 49 missense mutations, 3 nonsense mutations, one 1-bp deletion, one 5-bp deletion, one in frame 3-bp deletion, one insertion/deletion, 3 splice mutations, one 5'UTR mutation in MYH7, MYBPC3, TNNT2, TNNI3, CSRP3, MYH6 and MYL2 genes. Significantly 22 are novel gene mutations.
Conclusions
HRM was proven to be a technique with high sensitivity and a low false positive ratio allowing a rapid, innovative and low cost genotyping of HCM. In a short return, HRM as a gene scanning technique could be a cost-effective gene-based diagnosis for an accurate HCM genetic diagnosis and hopefully providing new insights into genotype/phenotype correlations.
doi:10.1186/1471-2350-13-17
PMCID: PMC3359199  PMID: 22429680
Hypertrophic cardiomyopathy; Gene-based diagnosis; High Resolution Melting; Sarcomere proteins; CSRP3 gene
3.  Cytogenetic characterization and genome size of the medicinal plant Catharanthus roseus (L.) G. Don 
AoB Plants  2012;2012:pls002.
The genome size and organization of the important medicinal plant Catharanthus roseus is shown to correspond to 1C = 0.76 pg (~738 Mbps) and 2n = 16 chromosomes. The data provide a sound basis for future studies including cytogenetic mapping, genomics and breeding.
Background and aims
Catharanthus roseus is a highly valuable medicinal plant producing several terpenoid indole alkaloids (TIAs) with pharmaceutical applications, including the anticancer agents vinblastine and vincristine. Due to the interest in its TIAs, C. roseus is one of the most extensively studied medicinal plants and has become a model species for the study of plant secondary metabolism. However, very little is known about the cytogenetics and genome size of this species, in spite of their importance for breeding programmes, TIA genetics and emerging genomic research. Therefore, the present paper provides a karyotype description and fluorescence in situ hybridization (FISH) data for C. roseus, as well as a rigorous characterization of its genome size.
Methodology
The organization of C. roseus chromosomes was characterized using several DNA/chromatin staining techniques and FISH of rDNA. Genome size was investigated by flow cytometry using an optimized methodology.
Principal results
The C. roseus full chromosome complement of 2n = 16 includes two metacentric, four subtelocentric and two telocentric chromosome pairs, with the presence of a single nucleolus organizer region in chromosome 6. An easy and reliable flow cytometry protocol for nuclear genome analysis of C. roseus was optimized, and the C-value of this species was estimated to be 1C = 0.76 pg, corresponding to 738 Mbp.
Conclusions
The organization and size of the C. roseus genome were characterized, providing an important basis for future studies of this important medicinal species, including further cytogenetic mapping, genomics, TIA genetics and breeding programmes.
doi:10.1093/aobpla/pls002
PMCID: PMC3292738  PMID: 22479673
4.  Filamentous Fungi in Drinking Water, Particularly in Relation to Biofilm Formation 
The presence of filamentous fungi in drinking water has become an area worthy of investigation with various studies now being published. The problems associated with fungi include blockage of water pipes, organoleptic deterioration, pathogenic fungi and mycotoxins. Fungal biofilm formation is a less developed field of study. This paper updates the topic and introduces novel methods on fungal biofilm analysis, particularly from work based in Brazil. Further recommendations for standard methodology are provided.
doi:10.3390/ijerph8020456
PMCID: PMC3084471  PMID: 21556196
fungal biofilms; drinking water; contaminants; filamentous fungi; water distribution system
5.  Lack of plasma albumin impairs intravascular lipolysis and explains the associated free fatty acids deficiency and hypertriglyceridemia 
Background
Abnormalities in lipid metabolism and transport are hallmarks in analbuminemic Nagase rats (NAR) and humans. Triglyceridemia is nearly 3- to 5-fold higher in female NAR than in control Sprague-Dawley rats (SDR). Also, NAR present with a severe plasma free fatty acid (FFA) deficit. There are conflicting results regarding the mechanisms underlying NAR hypertriglyceridemia.
Objective
We aimed at investigating whether liver lipogenesis and triglyceride secretion rates into the plasma contribute to the hypertriglyceridemia in NAR. We also studied whether heparin or albumin administration would release the hypothesized lipolysis inhibition in NAR.
Methods
The incorporation of tritiated water into lipids and the linear accumulation rate of plasma triglycerides after Triton WR1339 injection were the measures of liver lipogenesis and triglyceride secretion rates.
Results
Lipogenesis (596 ± 40 vs. 929 ± 124 μmol 3H2O/g/h) and triglyceride (4.25 ± 1.00 vs. 7.04 ± 1.68 mg/dL/min) secretion rates were slower (P ≤ 0.05) in fasted NAR than in control SDR. The injection of either heparin or albumin elicited an increase in NAR plasma FFA levels over time. FFA levels reached control levels 90 min after the albumin administration, increasing from 0.36 ± 0.05 to 1.34 ± 0.16 mEq/L (P ≤ 0.05). These results indicate that the lack of plasma albumin inhibits intravascular lipolysis and causes the FFA deficit observed in NAR.
Conclusion
NAR hepatic triglyceride synthesis and output do not contribute to NAR hypertriglyceridemia. We propose that the lack of albumin diminishes intravascular lipolysis which reduces the plasma triglyceride removal rate and explain both NAR hypertriglyceridemia and FFA deficiency.
doi:10.1186/1476-511X-9-146
PMCID: PMC3022753  PMID: 21187011
6.  Ciprofibrate increases cholesteryl ester transfer protein gene expression and the indirect reverse cholesterol transport to the liver 
Background
CETP is a plasma protein that modulates atherosclerosis risk through its HDL-cholesterol reducing action. The aim of this work was to examine the effect of the PPARα agonist, ciprofibrate, on the CETP gene expression, in the presence and absence of apolipoprotein (apo) CIII induced hypertriglyceridemia, and its impact on the HDL metabolism.
Results
Mice expressing apo CIII and/or CETP and non-transgenic littermates (CIII, CIII/CETP, CETP, non-Tg) were treated with ciprofibrate during 3 weeks. Drug treatment reduced plasma triglycerides (30-43%) and non-esterified fatty acids (19-47%) levels. Cholesterol (chol) distribution in plasma lipoprotein responses to ciprofibrate treatment was dependent on the genotypes. Treated CIII expressing mice presented elevation in VLDL-chol and reduction in HDL-chol. Treated CETP expressing mice responded with reduction in LDL-chol whereas in non-Tg mice the LDL-chol increased. In addition, ciprofibrate increased plasma post heparin lipoprotein lipase activity (1.3-2.1 fold) in all groups but hepatic lipase activity decreased in treated CETP and non-Tg mice. Plasma CETP activity and liver CETP mRNA levels were significantly increased in treated CIII/CETP and CETP mice (30-100%). Kinetic studies with 3H-cholesteryl ether (CEt) labelled HDL showed a 50% reduction in the 3H-CEt found in the LDL fraction in ciprofibrate treated compared to non-treated CETP mice. This means that 3H-CEt transferred from HDL to LDL was more efficiently removed from the plasma in the fibrate treated mice. Accordingly, the amount of 3H-CEt recovered in the liver 6 hours after HDL injection was increased by 35%.
Conclusion
Together these data showed that the PPARα agonist ciprofibrate stimulates CETP gene expression and changes the cholesterol flow through the reverse cholesterol transport, increasing plasma cholesterol removal through LDL.
doi:10.1186/1476-511X-8-50
PMCID: PMC2784759  PMID: 19930639
7.  Neonectria liriodendri sp. nov., the main causal agent of black foot disease of grapevines 
Studies in Mycology  2006;55:227-234.
Black foot disease is a serious disease of grapevine crops in most areas where vines are grown. Mainly two species of Cylindrocarpon, C. destructans and C. macrodidymum, are associated with this disease. Recent studies have revealed a tremendous molecular variation within the former but only slight molecular variation within the latter, indicating that C. destructans presents a complex of several species The present study elucidates the taxonomic status of C. destructans-like isolates associated with black foot disease of grapevines. Grapevine isolates were studied morphologically, subjected to DNA analyses of their ITS and partial β-tubulin genes, and were mated in all combinations in vitro. Cylindrocarpon destructans strains isolated from grapevines in Europe and South Africa appeared morphologically and genetically identical, and had identical ITS and partial β-tubulin gene sequences. Phylogenetic analyses placed these strains in a clade closely related but clearly distinct from other clades with C. destructans-like anamorphs obtained from various herbaceous or woody hosts. Only the ex-type strain of Cylindrocarpon liriodendri had identical sequences to strains isolated from grapevines, and could also not be distinguished by morphological characters. The grapevine isolates are therefore reidentified here as Cylindrocarpon liriodendri. Cylindrocarpn liriodendri formed perithecia in heterothallic conditions and the holomorph of this species is described as Neonectria liriodendri sp. nov. Neonectria liriodendri is genetically distinct from the ex-type strain of Neonectria radicicola, which originated from Cyclamen in Sweden. Both ex-type strains also differ from at least two other clades comprising additional C. destructans-like strains. Many of these strains originated from Panax sp., which is the host of the type of C. destructans. Our phylogenetic analyses indicate that C. destructans is not the anamorph of N. radicicola and that N. liriodendri, N. radicicola and several C. destructans-like taxa may have evolved independently within the same phylogenetic species complex.
PMCID: PMC2104714  PMID: 18490982
β-tubulin gene; black foot disease; Cylindrocarpon; internal transcribed spacer regions; Nectriaceae; phylogeny; systematics; Vitis
8.  High frequency of Fredrickson's phenotypes IV and IIb in Brazilians infected by human immunodeficiency virus 
Background
Human immunodeficiency virus (HIV) infection is very prevalent in Brazil. HIV therapy has been recently associated with coronary heart disease (CHD). Dyslipidemia is a major risk factor for CHD that is frequently described in HIV positive patients, but very few studies have been conducted in Brazilian patients evaluating their lipid profiles.
Methods
In the present work, we evaluated the frequency and severity of dyslipidemia in 257 Brazilian HIV positive patients. Two hundred and thirty-eight (93%) were submitted to antiretroviral therapy (224 treated with protease inhibitors plus nucleoside reverse transcriptase inhibitors, 14 treated only with the latter, 12 naive and 7 had no records of treatment).
The average time on drug treatment with antiretroviral therapy was 20 months. None of the patients was under lipid lowering drugs. Cholesterol, triglyceride, phospholipid and free fatty acids were determined by enzymatic colorimetric methods. Lipoprotein profile was estimated by the Friedewald formula and Fredrickson's phenotyping was obtained by serum electrophoresis on agarose. Apolipoprotein B and AI and lipoprotein "a" were measured by nephelometry.
Results
The Fredrickson phenotypes were: type IIb (51%), IV (41%), IIa (7%). In addition one patient was type III and another type V. Thirty-three percent of all HIV+ patients presented serum cholesterol levels ≥ 200 mg/dL, 61% LDL-cholesterol ≥ 100 mg/dL, 65% HDL-cholesterol below 40 mg/dL, 46% triglycerides ≥ 150 mg/dL and 10% have all these parameters above the limits. Eighty-six percent of patients had cholesterol/HDL-cholesterol ratio ≥ 3.5, 22% increased lipoprotein "a", 79% increased free fatty acids and 9% increased phospholipids. The treatment with protease inhibitors plus nucleoside reverse transcriptase inhibitors increased the levels of cholesterol and triglycerides in these patients when compared with naïve patients. The HDL-cholesterol (p = 0.01) and apolipoprotein A1 (p = 0.02) levels were inversely correlated with the time of protease inhibitor therapy while total cholesterol levels had a trend to correlate with antiretroviral therapy (p = 0.09).
Conclusion
The highly varied and prevalent types of dyslipidemia found in Brazilian HIV positive patients on antiretroviral therapies indicate the urgent need for their early diagnosis, the identification of the risk factors for CHD and, when needed, the prompt intervention on their lifestyle and/or with drug treatment.
doi:10.1186/1471-2334-5-47
PMCID: PMC1180436  PMID: 15955243
9.  Molecular and Phenotypic Analyses Reveal Association of Diverse Colletotrichum acutatum Groups and a Low Level of C. gloeosporioides with Olive Anthracnose 
Anthracnose (Colletotrichum spp.) is an important disease causing major yield losses and poor oil quality in olives. The objectives were to determine the diversity and distribution pattern of Colletotrichum spp. populations prevalent in olives and their relatedness to anthracnose pathogens in other hosts, assess their pathogenic variability and host preference, and develop diagnostic tools. A total of 128 Colletotrichum spp. isolates representing all olive-growing areas in Portugal and a few isolates from other countries were characterized by molecular and phenotypic assays and compared with reference isolates. Arbitrarily primed PCR data, internal transcribed spacer of rRNA gene and β-tubulin 2 nucleotide sequences, colony characteristics, and benomyl sensitivity showed Colletotrichum acutatum to be dominant (>97%) with limited occurrence of Colletotrichum gloeosporioides (<3%). Among C. acutatum populations, five molecular groups, A2 to A6, were identified. A2 was widely prevalent (89%), coinciding with a high incidence of anthracnose and environmental conditions suitable to disease spread. A4 was dominant in a particular region, while other C. acutatum groups and C. gloeosporioides were sporadic in their occurrence, mostly related to marginal areas of olive cultivation. C. gloeosporioides, isolated from olive fruits with symptoms indistinguishable from those of C. acutatum, showed same virulence rating as the most virulent C. acutatum isolate from group A2. C. acutatum and C. gloeosporioides isolates tested in infected strawberry fruits and strawberry and lupin plants revealed their cross-infection potential. Diagnostic tools were developed from β-tubulin 2 sequences to enable rapid and reliable pathogen detection and differentiation of C. acutatum groups.
doi:10.1128/AEM.71.6.2987-2998.2005
PMCID: PMC1151867  PMID: 15932994
10.  Effect of Cr(V) on reproductive organ morphology and sperm parameters: An experimental study in mice 
Background
Cr(V) species are formed during the intracellular reduction of Cr(VI), a ubiquitous environmental pollutant. In this study, the acute toxicity of a physiologically stable Cr(V) compound, [CrV-BT]2- (BT = bis(hydroxyethyl)aminotris(hydroxymethyl)methane) was investigated in the male reproductive system of sexually mature 60-day-old male ICR-CD1 mice.
Methods
Eight-week-old animals were subcutaneously injected daily with a dose of ca 8 μmol of Cr/mouse, during 5 days. The control group was injected with 0.5 mL of BT buffer. Testis and epididymis morphology was evaluated using light and transmission electron microscopy. Epididymal sperm counts, motility and acrosome integrity were also assayed using standard methods.
Results
Seminiferous epithelium abnormalities were detected in the CrV-BT experimental group, including intraepithelial vacuolation, and remarkable degeneration of Sertoli cells, spermatocytes and spermatids. The premature release of germ cells into the tubular lumen was also evident. Histological evaluation of epididymal compartments revealed apparently normal features. However, the epididymal epithelium presented vacuolation. [CrV-BT]2- induced a reduction in sperm acrosome integrity. However, sperm motility and density were not significantly affected.
Conclusion
This in vivo study using a Cr(V) compound, provides evidence for the potential reproductive hazards caused on male reproductive system by species containing chromium in intermediate oxidation states.
doi:10.1186/1476-069X-4-9
PMCID: PMC1187905  PMID: 15921522
11.  Sex differences in risk factors for coronary heart disease: a study in a Brazilian population 
BMC Public Health  2001;1:3.
Background
In Brazil coronary heart disease (CHD) constitutes the most important cause of death in both sexes in all the regions of the country and interestingly, the difference between the sexes in the CHD mortality rates is one of the smallest in the world because of high rates among women. Since a question has been raised about whether or how the incidence of several CHD risk factors differs between the sexes in Brazil the prevalence of various risk factors for CHD such as high blood cholesterol, diabetes mellitus, hypertension, obesity, sedentary lifestyle and cigarette smoking was compared between the sexes in a Brazilian population; also the relationships between blood cholesterol and the other risk factors were evaluated.
Results
The population presented high frequencies of all the risk factors evaluated. High blood cholesterol (CHOL) and hypertension were more prevalent among women as compared to men. Hypertension, diabetes and smoking showed equal or higher prevalence in women in pre-menopausal ages as compared to men. Obesity and physical inactivity were equally prevalent in both sexes respectively in the postmenopausal age group and at all ages. CHOL was associated with BMI, sex, age, hypertension and physical inactivity.
Conclusions
In this population the high prevalence of the CHD risk factors indicated that there is an urgent need for its control; the higher or equal prevalences of several risk factors in women could in part explain the high rates of mortality from CHD in females as compared to males.
doi:10.1186/1471-2458-1-3
PMCID: PMC31435  PMID: 11305930
12.  Plasma lipases and lipid transfer proteins increase phospholipid but not free cholesterol transfer from lipid emulsion to high density lipoproteins. 
BMC Biochemistry  2001;2:1.
Background
Plasma lipases and lipid transfer proteins are involved in the generation and speciation of high density lipoproteins. In this study we have examined the influence of plasma lipases and lipid transfer protein activities on the transfer of free cholesterol (FC) and phospholipids (PL) from lipid emulsion to human, rat and mouse lipoproteins. The effect of the lipases was verified by incubation of labeled (3H-FC,14C-PL) triglyceride rich emulsion with human plasma (control, post-heparin and post-heparin plus lipase inhibitor), rat plasma (control and post-heparin) and by the injection of the labeled lipid emulsion into control and heparinized functionally hepatectomized rats.
Results
In vitro, the lipase enriched plasma stimulated significantly the transfer of 14C-PL from emulsion to high density lipoprotein (p<0.001) but did not modify the transfer of 3H-FC. In hepatectomized rats, heparin stimulation of intravascular lipolysis increased the plasma removal of 14C-PL and the amount of 14C-PL found in the low density lipoprotein density fraction but not in the high density lipoprotein density fraction. The in vitro and in vivo experiments showed that free cholesterol and phospholipids were transferred from lipid emulsion to plasma lipoproteins independently from each other. The incubation of human plasma, control and control plus monoclonal antibody anti-cholesteryl ester transfer protein (CETP), with 14C-PL emulsion showed that CETP increases 14C-PL transfer to human HDL, since its partial inhibition by the anti-CETP antibody reduced significantly the 14C-PL transfer (p<0.05). However, comparing the nontransgenic (no CETP activity) with the CETP transgenic mouse plasma, no effect of CETP on the 14C-PL distribution in mice lipoproteins was observed.
Conclusions
It is concluded that: 1-intravascular lipases stimulate phospholipid transfer protein mediated phospholipid transfer, but not free cholesterol, from triglyceride rich particles to human high density lipoproteins and rat low density lipoproteins and high density lipoproteins; 2-free cholesterol and phospholipids are transferred from triglyceride rich particles to plasma lipoproteins by distinct mechanisms, and 3 - CETP also contributes to phospholipid transfer activity in human plasma but not in transgenic mice plasma, a species which has high levels of the specific phospholipid transfer protein activity.
doi:10.1186/1471-2091-2-1
PMCID: PMC31329  PMID: 11242564

Results 1-12 (12)