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Chemical Characterization of Auriferous Ores from the Brazilian State of Paraiba

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Journal of Minerals and Materials Characterization and Engineering 2015年第1期3卷 9-14页

作者： Marcelo rodrigues do Nascimento Artur M.G.lourenco Instituto Federal de Educacao Ciencia e Tecnologia da ParaibaLaboratorio de FlotacaoCampina GrandeBrazil Universidade Federal de Campina Grande Programa de Pos-Graduacao em Engenharia CivilCampina GrandeBrazil

One of the most important problems facing the gold industry is that the placer and free milling gold ores are almost terminating. Hence, the use of refractory ores has been increased during the recent years. In general, gold refractory ores occurs in various types of deposits associated with a range of minerals. Among the refractory ores, the sulfide type is the most common. The methodology employed in the mining process depends on the mode of occurrence of the ore and on the particle size, shape and degree of purity of the auriferous species. We have undertaken a mineralogical investigation of a representative sample of a complex gold mining ore collected in the municipality of Princesa Isabel, Paraiba, Brazil, using X-ray fluorescence spectrometry, X-ray diffractometry, infrared spectroscopy, inductively coupled plasma-atomic emission spectrometry and the Fire Assay. The results showed that the arsenic content of the ore was closely related to the gold content, and that the occurrence of “invisible gold” was associated primarily with pyrite and secondarily with arsenopyrite. The sulfur content of the ore was directly related to its refractoriness. It is concluded that gold mineralization in the study area is mainly of the gold-quartz-sulfide veins (lode gold), while the gold found in the mini-fractures of the deposits is probably associated with the hydrothermal processes that occurred in the region.

关键词： Auriferous Ore Chemical Characterization X-Ray Fluorescence Spectrometry X-Ray Diffractometry Inductively Coupled Plasma-Atomic Emission Spectrometry

Characterization and strong risk association of TLR2 del-196 to-174 polymorphism and Helicobacter pylori and their influence on mRNA expression in gastric cancer

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World Journal of Gastrointestinal Oncology 2020年第5期12卷 535-548页

作者： Caroline de Matos lourenco Manoela Dias Susi Mariah Cristina Antunes do Nascimento Vilson Serafim Junior Ana Paula Simedan Vila Gabriela Helena rodrigues-Flemming Eny Maria Goloni-Bertollo Ana Elizabete Silva Juliana Garcia de Oliveira-Cucolo Department of Graduate-Level Research Sacred Heart UniversityBauruSao Paulo 17011-970Brazil Department of Molecular Biology Sao Josédo Rio Preto School of MedicineSao Josédo Rio PretoSao Paulo 15090-000Brazil Department of Biology Sao Paulo State UniversitySao Josédo Rio PretoSao Paulo 15054-000Brazil

BACKGROUND Toll-like receptor-2(TLR2) is responsible for recognizing Helicobacter pylori(***) and activating the immune response. Polymorphisms in TLR2 may modulate gastric *** To evaluate whether the TLR2 19216 T/C(rs3804099) and TLR2-196 to-174 ins/del(rs111200466) polymorphisms contribute to gastric carcinogenesis in the Brazilian population, and to determine the influence of both polymorphisms and H. pylori infection on TLR2 mRNA *** DNA was extracted from 854 peripheral blood leukocyte or gastric tissue samples[202 gastric cancer(GC), 269 chronic gastritis(CG), and 383 control/healthy(C)]and genotyped by allele-specific PCR or restriction fragment length polymorphism(RFLP)-PCR. Quantitative polymerase chain reaction by Taq Man■ assay was used to quantify TLR2 mRNA levels in fresh gastric tissues(48 GC, 36 CG, and 14 C).RESULTS Regarding the TLR2-196 to -174 polymorphism, the ins/del and del/del genotypes were associated with a higher risk of GC by comparison with the C in all of the analyzed inheritance models(codominant, dominant, recessive, overdominant and log-additive;P < 0.0001). Similarly, an increased risk was observed when comparing the GC and CG groups [codominant(P < 0.0001), dominant(P <0.0001), recessive(P = 0.0260), overdominant(P < 0.0001) and log-additive(P <0.0001)]. In contrast, TLR2 19216 T/C was associated with a protective effect in the GC group compared to the C group [dominant(P = 0.0420) and log-additive(P =0.0300)]. Regarding the association of polymorphisms with H. pylori infection,individuals infected with H. pylori and harboring the TLR2-196 to-174 ins/del polymorphism had an increased risk of gastric carcinogenesis [codominant(P =0.0120), dominant(P = 0.0051), overdominant(P = 0.0240) and log-additive(P =0.0030)], while TLR2 19216 T/C was associated with a protective effect[codominant(P = 0.0039), dominant(P < 0.0001), overdominant(P = 0.0097) and log-additive(P = 0.0021)]. TLR2 mRNA levels were sig

关键词： Toll-like receptor 2 Helicobacter pylori Gastric cancer Chronic gastritis Polymorphisms Gene expression

Research on territory, environment and development

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Virtual Screening and Molecular Docking for Arylalkylamine-N-Acetyltransferase(aaNAT)Inhibitors,a Key Enzyme of Aedes(Stegomyia)aegypti(L.)Metabolism

2005年

作者： Nelson lourenco Carlos Russo Machado and Luis rodrigues.

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Computational Molecular Bioscience 2015年第3期5卷 35-44页

作者： Bruno Luis Alves lourenco Maicon Vinícius Araújo Santos Silva Elisson Barros de Oliveira Wagner rodrigues de Assis Soares Aristóteles Góes-Neto Gesivaldo Santos Bruno Silva Andrade Departamento de Saúde II Universidade Estadual do Sudoeste da Bahia (UESB) Jequié Brasil Departamento de Ciências Biológicas Universidade Estadual de Feira de Santana (UEFS) Feira de Santana Brasil Departamento de Ciências Biológicas Universidade Estadual do Sudoeste da Bahia (UESB) Jequié Brasil

Background: Dengue is a Neglected tropical disease (NTDs) with high incidence in Brazil. This disease is caused by Dengue virus and is transmitted by Aedes aegypti mosquito. The search for new approaches for controlling of this disease is the subject of numerous studies. The aaNAT is a key enzyme in the metabolism of A. aegypti and is crucial in the sclerotization process, as well as regulation of circadian rhythm and inactivation of neurotransmitters. Computational techniques applied to studies of biological systems become an effective weapon in the mapping and management of 3D data structures, giving direction and guidance of potential ligands that can form stable complexes with targets of interest, using a Molecular Docking approach. The present study was conducted by a virtual screening, followed by docking calculations, in order to find molecules that could inhibit aaNAT. In this study, we used available compounds in SAM database (Bioinformatics and Medicinal Chemistry Laboratory—Southwest Bahia State University, Jequié-Bahia, Brazil), PubChem and ZINC. Results: The result of dockings with selected ligands showed good energy affinities, presenting potential inhibitory interactions with the enzyme active site. Conclusions: The Coa-S-acetyl-tryptamine and 3-indoleacriloil-coenzyme-A showed the same binding energies -8.9 Kcal/Mol and were described as possible inhibitors of aaNAT.

关键词： Aedes aegypti aaNAT Virtual Screening Molecular Docking

Metabolic surgery and intestinal gene expression:Digestive tract and diabetes evolution considerations

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World Journal of Gastroenterology 2015年第22期21卷 6990-6998页

作者： Marcos Ricardo da Silva rodrigues Marco aurelio Santo Giovani Marino Favero Elaine Cristina Vieira Roberto Ferreira Artoni Viviane Nogaroto Egberto Gaspar de Moura Patricia Lisboa Fabio Quirillo Milleo Laboratório Multidisciplinar da Universidade Estadual de Ponta Grossa-Campus Uvaranas Avenida General Carlos Cavalcanti

AIM: To investigate the effects of bariatric surgery on metabolic parameters, incretin hormone secretion, and duodenal and ileal mucosal gene ***: Nine patients with type 2 diabetes mellitus(T2DM), chronic serum hyperglycemia for more than2 years, and a body mass index(BMI) of 30-35 kg/m2 underwent metabolic surgery sleeve gastrectomy with transit bipartition between May 2011 and December2011. Blood samples were collected pre and 3, 6 and12 mo postsurgery. Duodenal and ileal mucosa samples were collected pre- and 3 mo postsurgery. Pre- and postoperative blood samples were collected in the fasting state before ingestion of a standard meal(520kcal) and again 30, 60, 90, and 120 min after the mealto determine hemoglobin A1c(HbA1c) levels and the lipid profile, which consisted of triglyceride and total cholesterol levels. Intestinal gene expression of p53 and transforming growth factor(TGF)-β was analyzed using quantitative reverse-transcription PCR. Gastric inhibitory polypeptide(GIP) and glucagon-like peptide-1(GLP-1)were quantified using the enzyme-linked immunoassay method and analyzed pre- and ***'s t test or repeated measurements analysis of variance with Bonferroni corrections were performed as ***: BMI values decreased by 15.7% within the initial 3 mo after surgery(31.29 ± 0.73 vs 26.398± 0.68, P < 0.05) and then stabilized at 22% at 6mo postoperative, resulting in similar values 12 mo postoperatively(20-25 kg/m2). All of the patients experienced improved T2 DM, with 7 patients(78%)achieving complete remission(HbA1c < 6.5%), and 2patients(22%) achieving improved diabetes(HbA1c< 7.0% with or without the use of oral hypoglycemic agents). At 3 mo postoperatively, fasting plasma glucose had also decreased(59%)(269.55 ±18.24 mg/dL vs 100.77 ± 3.13 mg/dL, P < 0.05)with no further significant changes at 6 or 12 mo postoperatively. In the first month postoperatively,there was a complete withdrawal of hypoglycemic medica

关键词： Diabetes mellitus Hyperglycemia Intestine Gene expression Hyperplasia Bariatric surgery

Effect of Growth Regulators in Production and Rooting of Coffea arabica ***

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American Journal of Plant Sciences 2018年第4期9卷 628-636页

作者： Paulo Fernando Marques Cavalcanti Filho Diego Corona Baitelle Sílvio de Jesus Freitas Waldinei Souza da Silva Paulo Cesar dos Santos Weverton Pereira rodrigues Silverio de Paiva Freitas Ismael lourenco de Jesus Freitas Tamara Locatelli Abraao Carlos Verdin Filho Guilherme Bessa Miranda Department of Plant Science State University of Northern Rio de JaneiroCampos dos GoitacazesRio de Janeiro StateBrazil

The plants of C. arabica do not naturally produce a large number of orthotropic sprouts, hindering clonal multiplication by cutting, which would be the simplest technique with a lower cost of production compared to other methods of vegetative propagation. An alternative form, used successfully in the propagation of eucalyptus, is propagation by minicutting, which consists of pruning the shoot apex of the plant, forming the ministumps, which in variable time interval emits the shoots that will be used to make minicutting. In C. arabica plants the number of shoots can be increased with the application of growth regulators and fertilizers. So, the purpose of this work was to verify the effect of growth regulators and foliar fertilizers on the emission and development of orthotropic shoots of C. arabica. The experiment was installed in a randomized complete block design, with ten treatments composed by growth regulators and fertilizers: T1 (Control);T2 (Stimulate + Sturdy + Enervig);T3 (Stimulate + Vitakelp + Biozyme);T4 (Tiba + Sturdy + Enervig);T5 (Tiba + Vitakelp + Biozyme);T6 (Brs + Sturdy + Enervig) T7 (Brs + Vitakelp + Biozyme);T8 (Stimulate);T9 (TIBA);T10 (Brs-Brassinoesteroid), each plot consisting of two plants. Biometric and physiological parameters were evaluated for the ministumps, as well as the biometric parameters of the shoots and plant survival. The results showed that there was no influence of the treatments on the biometric parameters of the ministumps. A greater number of orthotopic sprouts were obtained in treatments with the TIBA growth regulator, as well as a greater plant survival of the minicuttings, after 25 days of transplanting in a greenhouse. It was concluded that TIBA treatments influenced the production and quality of clonal minicuttings of C. arabica.

关键词： Arabica Coffee Ministumps Clonal Propagation

Disentangling spatial,environmental and historical effects on tropical forest tree species turnover

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Journal of Plant Ecology 2021年第4期14卷 717-729页

作者： Alisson Borges Miranda Santos Vinicius Andrade Maia Cleber Rodrigo de Souza Nathalle Cristine Alencar Fagundes Fernanda Moreira Gianasi aurelio de Jesus rodrigues Pais Natalia de Aguiar-Campos Gabriela Gomes Pires Diego Teixeira Girardelli Jean Daniel Morel Mariana Caroline Moreira Morelli Felipe de Carvalho Araujo Rubens Manoel dos Santos Department of Forestry Sciences Federal University of LavrasUniversity CampusLavrasBrazil Biological Sciences University of the State of Minas GeraisItuiutaba UnitItuiutabaBrazil Department of Biology Federal University of LavrasUniversity CampusLavrasBrazil Faculty of Environmental Engineering and Natural Resources Zambeze UniversityChimoioMozambique

Aims We aimed at disentangling the effects of spatial distance,current and past environmental dissimilarity,and their combinations on tree community taxonomic and phylogenetic turnover by addressing the following questions:(i)Is tree community taxonomic and phylogenetic turnover related to the indirect effects of spatial distance via environmental dissimilarity?(ii)Does tree community taxonomic and phylogenetic turnover respond to paleoclimate(Last Glacial Maximum and Mid-Holocene)?Methods The study was carried out in 14 Atlantic rainforest sites in Brazil(20.4 ha sampled)containing 615 tree species from 83 plant *** obtained plot-level geographic coordinates and soil variables and site-level bioclimatic variables in the current,Mid-Holocene and Last Glacial *** used structural equation models with a distance-based approach to(i)test the direct effects of spatial distance and environmental dissimilarity and(ii)test the indirect effects of spatial distance via environmental dissimilarity on taxonomic(Bray–Curtis distance)and phylogenetic turnover(Comdist and Comdistnt distances).Important Findings Our results suggest a weak indirect effect of spatial distance via environmental dissimilarity on taxonomic and phylogenetic *** community turnover was driven by the direct effects of neutral,niche-based and historical ***,we inferred that the paleoclimate(historical processes)promoted the selection of the clades that gave rise to the current flora,while spatial distances(neutral processes)limited the dispersal range of species from the regional pool and environmental conditions(niche-based processes)locally selected the taxa that are able to persist.

关键词： assembly processes phylogenetic communities environmental filtering neutral communities phylogenetic turnover ecological niche paleoclimate effects