Functional diversity of bacterial genes associated with aromatic hydrocarbon degradation in anthropogenic dark earth of Amazonia

The objective of this work was to evaluate the catabolic gene diversity for the bacterial degradation of aromatic hydrocarbons in anthropogenic dark earth of Amazonia (ADE) and their biochar (BC). Functional diversity analyses in ADE soils can provide information on how adaptive microorganisms may influence the fertility of soils and what is their involvement in biogeochemical cycles. For this, clone libraries containing the gene encoding for the alpha subunit of aromatic ring-hydroxylating dioxygenases (α-ARHD bacterial gene) were constructed, totaling 800 clones. These libraries were prepared from samples of an ADE soil under two different land uses, located at the Caldeirão Experimental Station - secondary forest (SF) and agriculture (AG) -, and the biochar (SF_BC and AG_BC, respectively). Heterogeneity estimates indicated greater diversity in BC libraries; and Venn diagrams showed more unique operational protein clusters (OPC) in the SF_BC library than the ADE soil, which indicates that specific metabolic processes may occur in biochar. Phylogenetic analysis showed unidentified dioxygenases in ADE soils. Libraries containing functional gene encoding for the alpha subunit of the aromatic ring-hydroxylating dioxygenases (ARHD) gene from biochar show higher diversity indices than those of ADE under secondary forest and agriculture.

Gastric and colorectal cancer mortality in an urban and industrialized area of Brazil

PURPOSE: To study the gastric and colorectal cancer mortalities and their relation to the urban-industrialization in Baixada Santista, located in the southeastern region of Brazil. METHODS: Selected from the registries of the State System of Data Analysis Foundation (SEADE) were 1105 deaths due to gastric cancer (ICD 153--154) and 690 due to colorectal cancer (ICD 151) that occurred from 1980 to 1993 in males, above 10 years of age, residing in Baixada Santista. For each of these types of cancer, the standardized mortality rates, age-adjusted by world population in the 1960s, for 4 industrialized and 4 non-industrialized urban communities in that region were calculated. The ratios among those rates were calculated in order to compare the mortality in the periods 1980--93, 1980--1986, and 1987--1993. RESULTS: Standardized mortality rates for colorectal cancer were significantly higher in industrialized area, with ratios of 1.6 [95% CI 1.22 -- 2.29], 1.6 [95% CI 1.2 -- 2.0], and 1.6 [95% CI 1.3 -- 2.0] in the periods 1980--86, 1987--1993 and 1980--93, respectively. Gastric cancer did not show any statistical difference between the industrialized and non-industrialized areas, but there was a significant decrease in BS from the period 1980--1986 to 1987--1993. CONCLUSIONS: The significant elevation of colorectal cancer mortality in the industrialized area could be related to exposure to numerous carcinogens such as aromatic hydrocarbon, organic-chloride, metals, and industrial-port dust present in the region. Alternatively, the non-significant difference in gastric cancer between industrialized and non-industrialized areas and significant decrease in the last few years could be predominately reflecting the advances in the quality of life in urban areas. These results require further case-control studies that could help with the analysis of the associations among cancer and environmental factors (occupational, urban-industrial, habit, and life condition) and genetic susceptibility.

The cuticular hydrocarbons of the Triatoma sordida species subcomplex (Hemiptera: Reduviidae)

The cuticular hydrocarbons of the Triatoma sordida subcomplex (Hemiptera: Reduviidae: Triatominae) were ana-lysed by gas chromatography and their structures identified by mass spectrometry. They comprised mostly n-alkanes and methyl-branched alkanes with one-four methyl substitutions. n-alkanes consisted of a homologous series from C21-C33 and represented 33-45% of the hydrocarbon fraction; n-C29 was the major component. Methyl-branched alkanes showed alkyl chains from C24-C43. High molecular weight dimethyl and trimethylalkanes (from C35-C39) represented most of the methyl-branched fraction. A few tetramethylalkanes were also detected, comprising mostly even-numbered chains. Several components such as odd-numbered 3-methylalkanes, dimethylalkanes and trimethylalkanes of C37 and C39 showed patterns of variation that allowed the differentiation of the species and populations studied. Triatoma guasayana and Triatoma patagonica showed the most distinct hydrocarbon patterns within the subcomplex. The T. sordida populations from Brazil and Argentina showed significantly different hydrocarbon profiles that posed concerns regarding the homogeneity of the species. Triatoma garciabesi had a more complex hydrocarbon pattern, but it shared some similarity with T. sordida. The quantitative and qualitative variations in the cuticular hydrocarbons may help to elucidate the relationships between species and populations of this insect group.

Avaliação do destino e bioacumulação de benzo(a)pireno através de simulação computacional

The objective of this work was to evaluate the environmental distribution of benzo(a)pirene, a polycyclic aromatic hydrocarbon, by the EQC model. The modeling of the contaminant distribution was accomplished by means of the fugacity model applied to a hypothetical scenario constituted by air, water, soil and sediment. The modeling and simulations revealed that the soil is the preferential compartment. We also discuss the implications of the results about fate and ecological risks associated with benzo(a)pirene. We concluded that the emissions of HPAs can not be ignored and bioaccumulation among others risks can be induced.

Técnicas de extrações e procedimentos de clean-up para a determinação de hidrocarbonetos policílicos aromáticos (HPA) em sedimentos da costa do Ceará

Extraction and clean-up are essential points in polycyclic aromatic hydrocarbon (PAHs) analysis in a solid matrix. This work compares extraction techniques and clean-up procedures for PAH analysis. PAH levels, their toxicological significance and source were also evaluated in the waters of the Cocó and Ceará rivers. The efficiency of PAH recovery was higher for the soxhlet and ultrasonic techniques. PAH recovery varied from 69.3 to 99.3%. Total PAH concentration (ΣHPA) varied from 720.73 to 2234.76 µg kg-1 (Cocó river) and 96.4 to 1859.21 µg kg-1 (Ceará river). The main PAH sources are pyrolytic processes and the levels were classified as medium so that adverse effects are possible.

Avaliação geoquímica de óleos brasileiros com ênfase nos hidrocarbonetos aromáticos

Aromatic compounds are still poorly evaluated in geochemical studies of Brazilian oil samples. For this reason, the objective of this work was to analyze and evaluate 26 oil samples from four Brazilian sedimentary basins. Aromatic hydrocarbon fractions have been analyzed by gas chromatography coupled to mass spectrometry. The results were also compared with previously evaluated saturated hydrocarbon data. Maturation parameters obtained using the 4- and 1-methyl-dibenzothiophenes and trimethyl-dibenzothiophenes led to the best results because a better grouping was observed. For this correlation, the samples were grouped by maturity degree enabling the routine use of these parameters to evaluate oil maturity levels.

Modification of the performance of WO3-ZrO2 catalysts by metal addition in hydrocarbon reactions

A study of the different hydrocarbon reactions over Ni doped WO3-ZrO2 catalysts was performed. Ni was found as NiO at low Ni concentration while at high Ni concentrations a small fraction was present as a metal. For both cases, Ni strongly modified total acidity and concentration of strong acid sites. In the cyclohexane dehydrogenation reaction, Ni addition promotes both benzene and methyl cyclopentane production. The hydroconversion activity (n-butane and n-octane) increases with the augment of total acidity produced by Ni. The selectivity to reaction products is modified according to the acid strength distribution changes produced by Ni addition.

Hentriacontane: a leaf hydrocarbon from Syzygium jambos with stimulatory effects on the germination of urediniospores of Puccinia psidii

A crude Sohxlet extract from leaves of Syzygium jambos was sequentially fractionated using a silica gel flash column. A bioassay based on the numbers of urediniospores of Puccinia psidii that germinated in 2% water agar detected an active stimulant of germination when the fraction eluted with 100% n-hexane was used. The active fraction induced up to 88% increase in germination when added to a spore suspension in mineral oil. The active fraction was characterized as a hydrocarbon by ¹H nuclear magnetic resonance, 13C nuclear magnetic resonance, and infrared analysis. Gas chromatography-mass spectrometry analysis indicated that the fraction was a long-chain 436 MW hydrocarbon with corresponding to C31H64, namely hentriacontane. This is the first time such a compound proved to be involved with stimulation of fungal spore germination. These results may contribute to better understanding the infection process of rusts.

Polymorphism of the aryl-hydrocarbon receptor gene in intron 10 of human cancers

Polychlorinated dibenzo-p-dioxins (PCDDs) and related halogenated aromatic hydrocarbons (e.g., PCDFs), often called "dioxins", are ubiquitously present environmental contaminants. Some of them, notably 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), are among the most toxic synthetic compounds known. The biological effects of dioxins are mediated via the aryl hydrocarbon receptor (AhR). Mutations in the AhR transactivation domain are linked to sensitivity to the acute lethality of TCDD. We present here a study of AhR gene polymorphism in normal and cancer human tissues affecting pre-mRNA splicing in the AhR gene-coding transactivation domain region (exon 10, intron 10, exon 11 region), previously shown to be associated with AhR dysfunction. We tested 126 pairs of normal and cancer tissue samples from liver, lung, stomach, kidney, mucous, breast, and pancreas of 49 males and 77 females (45-70 years of age). We used in vitro splicing assay, RT-PCR and sequencing methods. Our results showed that in an in vitro system it is possible to reconstitute cellular pre-mRNA splicing events. Tested cancer tissues did not contain mutations in the AhR transactivation domain region when the DNA sequences were compared with those from normal tissues. There were also no differences in AhR mRNA splice variants between normal and malignant breast tissues and no polymorphisms in the studied regions or cDNA.

Diabetes burden in Brazil: fraction attributable to overweight, obesity, and excess weight

OBJECTIVE To estimate the burden of type 2 diabetes mellitus and its percentage attributable to overweight and obesity in Brazil.METHODS The burden of diabetes mellitus was described in terms of disability-adjusted life years, which is the sum of two components: years of life lost and years lived with disability. To calculate the fraction of diabetes mellitus attributable to overweight, obesity, and excess weight, we used the prevalence of these risk factors according to sex and age groups (> 20 years) obtained from the 2008 Pesquisa Dimensões Sociais das Desigualdades (Social Dimensions of Inequality Survey) and the relative risks derived from the international literature.RESULTS Diabetes mellitus accounted for 5.4% of Brazilian disability-adjusted life years in 2008, with the largest fraction attributed to the morbidity component (years lived with disability). Women exhibited higher values for disability-adjusted life years. In Brazil, 49.2%, 58.3%, and 70.6% of diabetes mellitus in women was attributable to overweight, obesity, and excess weight, respectively. Among men, these percentages were 40.5%, 45.4%, and 60.3%, respectively. Differences were observed with respect to Brazilian regions and age groups.CONCLUSIONS A large fraction of diabetes mellitus was attributable to preventable individual risk factors and, in about six years, the contribution of these factors significant increased, particularly among men. Policies aimed at promoting healthy lifestyle habits, such as a balanced diet and physical activity, can have a significant impact on reducing the burden of diabetes mellitus in Brazil.

Hydrophobic fraction of Taenia saginata metacestodes, rather than hydrophilic fraction, contains immunodominant markers for diagnosing human neurocysticercosis

INTRODUCTION: Considering that alternative antigens for diagnosing neurocysticercosis continue to be a challenge because of the increasing difficulty in obtaining parasites from naturally infected pigs for preparation of Taenia solium homologous antigen, the aim of the present study was to evaluate the detergent (D) and aqueous (A) fractions from saline extract of Taenia saginata metacestodes for diagnosing neurocysticercosis. METHODS: Taenia saginata was obtained from naturally infected bovines in the Triângulo Mineiro region, State of Minas Gerais, Brazil. The carcasses came from cold storage units and had been slaughtered in accordance with the inspection technique recommended by the Federal Inspection Service. The D and A fractions were obtained by using Triton X-114 (TX-114). Serum samples were obtained from 40 patients with a diagnosis of neurocysticercosis, 45 with other parasitic diseases and 30 from apparently normal individuals. IgG antibody levels were evaluated using the ELISA and immunoblotting assays. RESULTS: The ELISA sensitivity and specificity were 95% and 73.3%, when using saline extract; 95% and 82.6% for the D fraction; and 65% and 61.3% for the A fraction, respectively. The immunoblotting assay confirmed the ELISA results, such that the D fraction was more efficient than the other extracts, and the 70-68kDa component was immunodominant among neurocysticercosis patients. CONCLUSIONS: These results demonstrated that the D fraction from Taenia saginata metacestodes obtained using TX-114 can be used as a heterologous antigenic fraction in the immunoblotting assay for serologically diagnosing human neurocysticercosis, given its ability to select immunodominant antigens.

High molecular mass fraction in clinical isolates of Paracoccidioides brasiliensis

INTRODUCTION: Different serum levels of the IgG/IgE for Paracoccidioides brasiliensis high mass molecular (hMM) fraction (~366kDa) in the acute and chronic forms of the disease have been reported. Considering the nonexistence of hMM fraction investigation involving clinical isolates of P. brasiliensis, the present study aimed to investigate the presence of the hMM fraction (~366kDa) in cell free antigens (CFA) from P. brasiliensis clinical isolates. METHODS: CFA from 10 clinical isolates and a reference strain (Pb18) were submitted to SDS-polyacrylamide gel electrophoresis (SDS-PAGE) followed by gel image capturing and densitometer analysis. Additionally, CFA from 20 isolates and Pb18 were analyzed by capture ELISA (cELISA) using polyclonal (polAb) or monoclonal (mAb) antibodies to the hMM fraction. RESULTS: The presence of the hMM component was observed in CFA of all samples analyzed by SDS-PAGE/densitometry and by cELISA. In addition, Pearson's correlation test demonstrated stronger coefficients between hMM fraction levels using pAb and mAb (R = 0.853) in cELISA. CONCLUSIONS: The soluble hMM fraction was present in all the P. brasiliensis clinical isolates analyzed and the reference strain Pb18, which could be used as a source of this antigen. The work also introduces for first time, the cELISA method for P. brasiliensis hMM fraction detection. Analysis also suggests that detection is viable using polAb or mAb and this methodology may be useful for future investigation of the soluble hMM fraction (~366kDa) in sera from PCM patients.

Mildly symptomatic chronic mitral regurgitation. Analysis of left ventricular systolic function and mitral regurgitant fraction under pharmacological influence: echocardiographic study

OBJECTIVE: To study echocardiographic parameters of left ventricular systolic function and valvar regurgitation under pharmacological influence in mildly symptomatic patients with chronic mitral regurgitation (MR). METHODS: We carried out a double-blind placebo controlled study in 12 patients with MR, mean aged 12.5 years old, who were randomized in 4 phases: A) digoxin; B) enalapril; C) digoxin + enalapril; D) placebo. The medication was administered for 30 days in each phase, and the following variables were analyzed: shortening and ejection fractions, wall stress index of left ventricle, left ventricular meridional end-systolic wall stress, Doppler-derived mean rate of left ventricular pressure rise (mean dP/dt), stroke volume and MR jet area. The clinical variables analysed were heart rate and systemic arterial pressure. RESULTS: No significant variation was observed in the clinical variables analysed. The shortening and ejection fraction, the mean dP/dt and stroke volume significantly increased and the wall stress index of left ventricle, the meridional left ventricular end systolic wall stress and the mitral regurgitation jet area decreased in the phases with medication as compared with that in the placebo phase. CONCLUSION: The parameters of left ventricular systolic function improved significantly and the degree of MR decreased with the isolated administration of digoxin or enalapril in mildly symptomatic patients with chronic MR. The combination of the drugs, however, did not show better results.

Assessing Strategies for Heart Failure with Preserved Ejection Fraction at the Outpatient Clinic

Background: Heart failure with preserved ejection fraction (HFPEF) is the most common form of heart failure (HF), its diagnosis being a challenge to the outpatient clinic practice. Objective: To describe and compare two strategies derived from algorithms of the European Society of Cardiology Diastology Guidelines for the diagnosis of HFPEF. Methods: Cross-sectional study with 166 consecutive ambulatory patients (67.9±11.7 years; 72% of women). The strategies to confirm HFPEF were established according to the European Society of Cardiology Diastology Guidelines criteria. In strategy 1 (S1), tissue Doppler echocardiography (TDE) and electrocardiography (ECG) were used; in strategy 2 (S2), B-type natriuretic peptide (BNP) measurement was included. Results: In S1, patients were divided into groups based on the E/E'ratio as follows: GI, E/E'> 15 (n = 16; 9%); GII, E/E'8 to 15 (n = 79; 48%); and GIII, E/E'< 8 (n = 71; 43%). HFPEF was confirmed in GI and excluded in GIII. In GII, TDE [left atrial volume index (LAVI) ≥ 40 mL/m2; left ventricular mass index LVMI) > 122 for women and > 149 g/m2 for men] and ECG (atrial fibrillation) parameters were assessed, confirming HFPEF in 33 more patients, adding up to 49 (29%). In S2, patients were divided into three groups based on BNP levels. GI (BNP > 200 pg/mL) consisted of 12 patients, HFPEF being confirmed in all of them. GII (BNP ranging from 100 to 200 pg/mL) consisted of 20 patients with LAVI > 29 mL/m2, or LVMI ≥ 96 g/m2 for women or ≥ 116 g/m2 for men, or E/E'≥ 8 or atrial fibrillation on ECG, and the diagnosis of HFPEF was confirmed in 15. GIII (BNP < 100 pg/mL) consisted of 134 patients, 26 of whom had the diagnosis of HFPEF confirmed when GII parameters were used. Measuring BNP levels in S2 identified 4 more patients (8%) with HFPEF as compared with those identified in S1. Conclusion: The association of BNP measurement and TDE data is better than the isolated use of those parameters. BNP can be useful in identifying patients whose diagnosis of HF had been previously excluded based only on TDE findings.