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1.
An Acad Bras Cienc ; 95(suppl 2): e20210997, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126517

RESUMO

In this study, we tested the taxonomic validation of red snappers species (Southern red snapper Lutjanus purpureus; Silk snapper L. vivanus; Blackfin snapper L. buccanella; and Pacific red snapper L. peru) based on comparative analysis, using four methods for species delimitation. These methods were based on either genetic similarity or phylogenetic trees inferred from two mitochondrial (Cytochrome b and D-loop) and two nuclear (Myostatin and S7 introns) markers. On one hand, the genetic results corroborated the presence of four red snapper species, confirming their taxonomic validation despite their remarkable morphological similarity. On the other hand, few incongruencies in the species delimitation methods were observed according to the phylogenetic reconstruction method (maximum likelihood or Bayesian inference) when using. Based on the phylogenetic results, L. buccanella should represent a more ancient lineage in relation to the clade that encompasses L. purpureus, L. peru and L. vivanus. The single-locus phylogenetic analysis based on Cytb recovered each the red snapper species as a well-supported clade. Overall, this study provided a DNA-based validation of the traditional morphological taxonomy of red snappers.


Assuntos
Peixes , Perciformes , Animais , Filogenia , Teorema de Bayes , Perciformes/genética , Peru
2.
Entropy (Basel) ; 24(9)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36141111

RESUMO

We report an analysis of the distribution of lengths of plant DNA (exons). Three species of Cucurbitaceae were investigated. In our study, we used two distinct κ distribution functions, namely, κ-Maxwellian and double-κ, to fit the length distributions. To determine which distribution has the best fitting, we made a Bayesian analysis of the models. Furthermore, we filtered the data, removing outliers, through a box plot analysis. Our findings show that the sum of κ-exponentials is the most appropriate to adjust the distribution curves and that the values of the κ parameter do not undergo considerable changes after filtering. Furthermore, for the analyzed species, there is a tendency for the κ parameter to lay within the interval (0.27;0.43).

3.
J Bioenerg Biomembr ; 53(2): 149-156, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33635515

RESUMO

The present study aimed to evaluate the in vitro efflux pump inhibitory capacity of hydroxyamines derived from lapachol and norlachol, where compounds 3, 4, and 5 were tested against the S. aureus strains: RN4220 carrying the pUL5054 plasmid; and IS-58, endowed with the PT181 plasmid. The substances were synthesized from 2-hydroxy-quinones, lapachol and nor-lapachol obtaining the corresponding 2-methoxylated derivatives via dimethyl sulfate alkylation in a basic medium, which then reacted chemoselectively with 2-ethanolamine and 3-propanolamine to form the corresponding amino alcohols. The antibacterial action of the substances was quantified by determining the Minimum Inhibitory Concentration (MIC), while a microdilution assay was carried out to ascertain efflux pump inhibition of Staphylococcus aureus strains carrying the MsrA macrolide and the TetK tetracycline efflux pumps with the substances at a sub-inhibitory concentration. The results were subjected to statistical analysis by an ANOVA test and Bonferroni post hoc test. The MIC from the substances exhibited a value ≥ 1024 µg/mL. However, a significant reduction (p < 0.0001) of the erythromycin, tetracycline and ethidium bromide MIC was demonstrated when these were in combination with the substances, with this effect being due to a supposed efflux pump inhibition. The tested substances demonstrated effectiveness at decreasing the MIC of erythromycin, tetracycline and ethidium bromide, potentially by inhibiting the MsrA macrolide and the TetK tetracycline efflux pumps present in the tested S. aureus strains.


Assuntos
Antibacterianos/uso terapêutico , Naftoquinonas/uso terapêutico , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Naftoquinonas/farmacologia
4.
Mol Phylogenet Evol ; 147: 106780, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32135307

RESUMO

Lutjanus campechanus and Lutjanus purpureus are two commercially important lutjanid fishes (snappers) with non-sympatric distribution throughout Western Atlantic. Even though both taxa have traditionally been regarded as valid species, their taxonomic status remains under debate. In the present study, we used phylogeographic approaches and molecular methods of species delimitation to elucidate the taxonomic issues between both species, based on 1478 base pairs from four genomic regions. We found haplotypes shared between the two species, particularly in relation to nuclear DNA (nuDNA) sequences. The molecular delimitation of species supported the discrimination of L. purpureus and L. campechanus as distinct evolutionary units. Nonetheless, a unidirectional gene flow was found from L. campechanus towards L. purpureus. Therefore, it seems plausible to infer that L. campechanus and L. purpureus are two evolutionary units in which the apparent sharing of haplotypes should be driven by introgression.


Assuntos
Loci Gênicos , Perciformes/classificação , Perciformes/genética , Animais , Bases de Dados Genéticas , Genética Populacional , Genoma , Geografia , Haplótipos/genética , Filogenia , Especificidade da Espécie
5.
Proc Biol Sci ; 286(1900): 20182924, 2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30940064

RESUMO

Species delimitation is a major quest in biology and is essential for adequate management of the organismal diversity. A challenging example comprises the fish species of red snappers in the Western Atlantic. Red snappers have been traditionally recognized as two separate species based on morphology: Lutjanus campechanus (northern red snapper) and L. purpureus (southern red snapper). Recent genetic studies using mitochondrial markers, however, failed to delineate these nominal species, leading to the current lumping of the northern and southern populations into a single species ( L. campechanus). This decision carries broad implications for conservation and management as red snappers have been commercially over-exploited across the Western Atlantic and are currently listed as vulnerable. To address this conflict, we examine genome-wide data collected throughout the range of the two species. Population genomics, phylogenetic and coalescent analyses favour the existence of two independent evolutionary lineages, a result that confirms the morphology-based delimitation scenario in agreement with conventional taxonomy. Despite finding evidence of introgression in geographically neighbouring populations in northern South America, our genomic analyses strongly support isolation and differentiation of these species, suggesting that the northern and southern red snappers should be treated as distinct taxonomic entities.


Assuntos
Especiação Genética , Perciformes/classificação , Animais , Oceano Atlântico , Região do Caribe , DNA Mitocondrial/análise , Genoma , Golfo do México , Perciformes/anatomia & histologia , Perciformes/genética , Filogenia
6.
An Acad Bras Cienc ; 89(3 Suppl): 2095-2100, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28678957

RESUMO

In the present study, a novel set of eight EPIC primers were developed for Lutjanus purpureus and assayed in five other marine teleosts including three lutjanids, one scianid and one anablepid. Most of the genomic regions used in this study presented genetic diversity indexes equal or greater than the intragenic regions commonly used in population genetics studies. Moreover, six out of eight markers showed cross-amplification with other taxa. Thus, the primers described here may be used to elucidate questions at the intraspecific level for a large number of taxa.


Assuntos
Perciformes/genética , Reação em Cadeia da Polimerase/métodos , Animais , Marcadores Genéticos , Variação Genética , Genética Populacional , Perciformes/classificação , Filogenia , Análise de Sequência de DNA
7.
Microb Pathog ; 97: 9-13, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27057677

RESUMO

During the early periods of antibiotic usage, bacterial infections were considered tamed. However, widespread antibiotic use has promoted the emergence of antibiotic-resistant pathogens, including multidrug resistant strains. Active efflux is a mechanism for bacterial resistance to inhibitory substances, known simply as drug efflux pumps. The bacterium Staphylococcus aureus is an important pathogenic bacterium responsible for an array of infections. The NorA efflux pump has been shown to be responsible for moderate fluoroquinolone resistance of S. aureus. The inhibition of the efflux pump was assayed using a sub-inhibitory concentration of standard efflux pump inhibitors and tannic acid (MIC/8), where its capacity to decrease the MIC of Ethidium bromide (EtBr) and antibiotics due to the possible inhibitory effect of these substances was observed. The MICs of EtBr and antibiotics were significantly reduced in the presence of tannic acid, indicating the inhibitory effect of this agent against the efflux pumps of both strains causing a three-fold reduction of the MIC when compared with the control. These results indicate the possible usage of tannic acid as an adjuvant in antibiotic therapy against multidrug resistant bacteria (MDR).


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Staphylococcus aureus/efeitos dos fármacos , Taninos/farmacologia , Etídio/farmacologia , Testes de Sensibilidade Microbiana
8.
Molecules ; 20(8): 15434-48, 2015 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-26305244

RESUMO

Lipid supplements (oilseeds vegetables) are included in ruminant diet to increase its energy density and improve fatty acid composition of milk and consequently of fresh cheese. Milk and cheeses were evaluated from crossbred Holstein × Zebu, fed diets enriched with 0%, 25%, 50%, and 75% inclusion levels of palm kernel cake in concentrated supplement, which were supplied daily (3.0 kg). Milk and fresh cheese (p = 0.001) fatty acids C12:0 exhibited quadratic negative values. Milk fatty acids C13:0, C20:0, C18:2t10c12, and C20:2n-6 presented positive quadratic values. The milk C18:2n-6 decreased linearly and in fresh cheese exhibited an increasing linear effect (p = 0.016). However, the fatty acids grouped in milk fat were not affected. The medium-chain fatty acids varied negatively and quadratically (p = 0.045). There was no effect on milk and fresh cheese chemical composition (p > 0.05). The milk fat was increased (p = 0.0065) quadratically (minimum point of 24.7%). Thus, the addition of palm kernel cake to cow diets negatively altered the fatty acid profile, it raises the percentage of lauric (C12) and tridecanoic (C13) acids fat which is not beneficial to human health from a nutraceutical perspective, although it did not influence the atherogenicity index.


Assuntos
Arecaceae/química , Queijo/análise , Indústria de Laticínios , Dieta , Suplementos Nutricionais , Ácidos Graxos/análise , Leite/química , Animais , Bovinos , Isomerismo , Ácidos Linoleicos Conjugados/química
9.
BMC Pregnancy Childbirth ; 14: 266, 2014 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-25108701

RESUMO

BACKGROUND: Over the last decades there has been a reduction of social inequalities in Brazil, as well as a strong expansion of health services, including prenatal care. The objective of the present study was to estimate the rate of inadequate prenatal care utilization and its associated factors in São Luís, Brazil, in 2010 and to determine whether there was a reduction of inequity in prenatal care use by comparing the present data to those obtained from a previous cohort started in 1997/98. METHODS: Data from the BRISA (Brazilian birth cohort studies of Ribeirão Preto and São Luís) population-based cohort, which started in 2010 (5067 women), were used. The outcome variable was the inadequate utilization of prenatal care, classified according to the recommendations of the Brazilian Ministry of Health. The explanatory variables were organized into three hierarchical levels based on the Andersen's behavioral model of the use of health services: predisposing, enabling and need factors. RESULTS: Only 2.0% of the women did not attend at least one prenatal care visit. The rate of inadequate prenatal care utilization was 36.7%. Despite an improved adequacy of prenatal care use from 47.3% in 1997/98 to 58.2% in 2010, social inequality persisted: both low maternal schooling (prevalence ratio (PR) = 2.78; 95% confidence interval (95% CI) 2.23-3.47 for 0 to 4 years of study) and low family income, less than 0.5 monthly minimum wage per capita (PR = 1.37; 95% CI 1.22-1. 54), continued to be associated with higher rates of inadequate prenatal care utilization. Racial disparity regarding adequate utilization of prenatal services was detected, with black (PR = 1.19; 95% CI 1.04-1.36) and mulatto (PR = 1.14; 95% CI 1.02-1.26) women showing higher rates of inadequate use. On the other hand, women covered by the FHP - Family Health Program (PR = 0.92; 95% CI 0.85-0.98) showed a lower rate of inadequate prenatal care utilization. CONCLUSIONS: Despite strong expansion of health services and expressive improvements in adequate prenatal care use and social indicators, inequalities in prenatal care use still persist. The FHP seems to be effective in reducing inadequate prenatal care utilization.


Assuntos
Programas Governamentais , Disparidades em Assistência à Saúde/tendências , Cuidado Pré-Natal/estatística & dados numéricos , Cuidado Pré-Natal/tendências , Adulto , Consumo de Bebidas Alcoólicas , População Negra/estatística & dados numéricos , Brasil , Estudos Transversais , Feminino , Disparidades em Assistência à Saúde/etnologia , Humanos , Renda , Mães/educação , Gravidez , Fumar , Adulto Jovem
10.
Materials (Basel) ; 17(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38793394

RESUMO

This study investigates the tribocorrosion performance of a cast Co-Cr-Mo alloy prepared using casting and electromagnetic stirring (EMS) at specific frequencies. The tribocorrosion behaviour of the alloy was evaluated when exposed to Ringer's lactate solution to optimize the EMS parameters and improve its properties. The research focuses on biomedical implant applications and explores how EMS affects alloy wear and corrosion resistance. As did the friction coefficient and wear volume, the wear rate of samples produced with EMS frequencies of 75 Hz and 150 Hz decreased. These improvements are attributed to the ability of EMS to refine grain size and homogenize the microstructure, thereby increasing the resistance to tribocorrosion. Techniques such as scanning electron microscopy (SEM) and profilometry were used for surface and wear analysis, while mechanical properties were evaluated through instrumented indentation tests. The findings confirm that EMS improves the alloy's durability and tribocorrosion resistance, making it highly suitable for demanding biomedical applications such as joint replacements. This highlights the importance of advanced manufacturing techniques in optimizing biomedical alloys for simulated body conditions.

11.
PeerJ ; 11: e15973, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37780387

RESUMO

Previous studies about the genetic diversity, connectivity and demographic history in Lutjanidae fishes have reported a common pattern of genetic homogeneity and expansion in populations from Western South Atlantic. In the present work, we inferred the population structure, the levels of genetic diversity and the demographic history of the Brazilian snapper Lutjanus alexandrei, a recently described and endemic species from Northeastern coast of Brazil. Five different fragments, including mitochondrial DNA (Control Region, Cyt b and ND4) and nuclear DNA (Myostatin and S7) regions were analyzed in 120 specimens of L. alexandrei from four localities in Northeastern Brazil, representing the first study of population genetics in this species. High levels of genetic diversity were observed following a panmictic pattern, probably related to the larval dispersal by the current tides along the Brazilian coast. In addition, both demographic history and neutrality tests indicated that L. alexandrei has undergone population expansion during Pleistocene. In this sense, the sea level variation from this period could have increased the available resources and suitable habitats for the Brazilian snapper.


Assuntos
Peixes , Perciformes , Animais , Brasil/epidemiologia , Peixes/genética , Perciformes/genética , Genética Populacional , DNA Mitocondrial/genética
12.
Sci Rep ; 13(1): 19749, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957204

RESUMO

This study aimed to identify the teleost fish species sold in Bragança, a major fishing hub on the north coast of Brazil. The COI gene analysis was performed for the identification of fish species. The local market uses common names that are not accurate and do not reflect the diversity of the species. 204 sequences were obtained, with 119 haplotypes. 83 species were identified by comparing with public databases and constructing phylogenetic trees, with Carangidae being the most prevalent family. The study also found Haemulon atlanticus, Menticirrhus cuiaranensis and Hoplias misioneira, a newly described species from the Amazon basin, among the samples. Additionally, 73 commercial names were recorded, including 10 categories, and the illegal trade of Epinephelus itajara was detected. The DNA Barcode method proved to be effective for discriminating the species. The study highlights that common and commercial names are vague and underestimate the fish diversity, and that Brazil needs to revise its regulations for commercial and scientific names.


Assuntos
Espécies em Perigo de Extinção , Perciformes , Animais , Código de Barras de DNA Taxonômico , Filogenia , DNA
13.
Materials (Basel) ; 16(7)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37049218

RESUMO

Cobalt-chromium-molybdenum (Co-Cr-Mo) alloy is a material recommended for biomedical implants; however, to be suitable for this application, it should have good tribological properties, which are related to grain size. This paper investigates the tribological behaviour of a Co-Cr-Mo alloy produced using investment casting, together with electromagnetic stirring, to reduce its grain size. The samples were subjected to wear and scratch tests in simulated body fluid (Ringer's lactate solution). Since a reduction in grain size can influence the behaviour of the material, in terms of resistance and tribological response, four samples with different grain sizes were produced for use in our investigation of the behaviour of the alloy, in which we considered the friction coefficient, wear, and scratch resistance. The experiments were performed using a tribometer, with mean values for the friction coefficient, normal load, and tangential force acquired and recorded by the software. Spheres of Ti-6Al-4V and 316L steel were used as counterface materials. In addition, to elucidate the influence of grain size on the mechanical properties of the alloy, observations were conducted via scanning electron microscopy (SEM) with electron backscatter diffraction (EBSD). The results showed changes in the structure, with a reduction in grain size from 5.51 to 0.79 mm. Using both spheres, the best results for the friction coefficient and wear volume corresponded to the sample with the smallest grain size of 0.79 mm. The friction coefficients obtained were 0.37 and 0.45, using the Ti-6Al-4V and 316L spheres, respectively. These results confirm that the best surface finish for Co-Cr-Mo alloy used as a biomedical implant is one with a smaller grain size, since this results in a lower friction coefficient and low wear.

14.
PLoS One ; 18(9): e0292232, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37768976

RESUMO

The efficiency of the DNA barcoding relies on sequencing fragment of the Cytochrome C Subunit I (COI) gene, which has been claimed as a tool to biodiversity identification from distinct groups. Accordingly, the goal of this study was to identify juvenile fish species along an estuary of Caeté River in the Brazilian Blue Amazon based on. For this purpose, we applied the DNA barcoding and discuss this approach as a tool for discrimination of species in early ontogenetic stages. A 500-bp fragment was obtained from 74 individuals, belonging to 23 species, 20 genera, 13 families and seven orders. About 70% of the 46 haplotypes revealed congruence between morphological and molecular species identification, while 8% of them failed in identification of taxa and 22% demonstrated morphological misidentification. These results proved that COI fragments were effective to diagnose fish species at early life stages, allowing identifying all samples to a species-specific status, except for some taxa whose COI sequences remain unavailable in public databases. Therefore, we recommend the incorporation of DNA barcoding to provide additional support to traditional identification, especially in morphologically controversial groups. In addition, periodic updates and comparative analyses in public COI datasets are encouraged.


Assuntos
Código de Barras de DNA Taxonômico , Estuários , Humanos , Animais , Código de Barras de DNA Taxonômico/métodos , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Filogenia , Peixes , DNA/genética
15.
Viruses ; 14(10)2022 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-36298656

RESUMO

The rapid and disorderly urbanization in the Amazon has resulted in the insertion of forest fragments into cities, causing the circulation of arboviruses, which can involve hematophagous arthropods and free-ranging birds in the transmission cycles in urban environments. This study aimed to evaluate the circulation of arboviruses in free-ranging birds and hematophagous arthropods captured in an Environmental Protection Area in the Belem metropolitan area, Brazil. Birds were captured using mist nets, and hematophagous arthropods were collected using a human protected attraction technique and light traps. The birds' sera were subjected to a hemagglutination inhibition test to detect antibodies against 29 arbovirus antigens. Arthropod macerates were inoculated into C6/36 and VERO cell cultures to attempt viral isolation and were tested using indirect immunofluorescence, subsequent genetic sequencing and submitted for phylogenetic analysis. Four bird sera were positive for arbovirus, and one batch of Psorophora ferox was positive for Flavivirus on viral isolation and indirect immunofluorescence. In addition, the Ilheus virus was detected in the sequencing and phylogenetic analysis. The presence of antibodies in sera from free-ranging birds and the isolation of Ilheus virus in Psorophora ferox indicate the circulation of arboviruses in forest remnants in the urban center of Belem.


Assuntos
Infecções por Arbovirus , Arbovírus , Artrópodes , Culicidae , Animais , Humanos , Conservação dos Recursos Naturais , Nematóceros , Filogenia , Aves , Florestas , Ecossistema , Infecções por Arbovirus/veterinária
16.
Breast Cancer Res Treat ; 125(1): 261-4, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20734131

RESUMO

Breast cancer represents a serious public health problem worldwide, for its high incidence, morbidity, mortality, and its high cost treatment. It is known that breast cancer is a multifactorial disease, possessing various risk factors, among which include hormonal factors, genetic and environmental. The role of viruses in breast carcinogenesis is controversial. This study aims to evaluate the expression of HPV 6, 11, 16, and 18 by polymerase chain reaction (PCR) in invasive ductal breast carcinoma. We analyzed 90 women diagnosed with invasive ductal breast carcinoma, of which the extracted DNA was amplified, quantified and tested for DNA subtypes 6, 11, 16, and 18 by PCR. The research carried out in 79 samples of HPV DNA, proved negative. Our study demonstrates no association between the most prevalent types of HPV and breast cancer.


Assuntos
Alphapapillomavirus/isolamento & purificação , Neoplasias da Mama/virologia , Carcinoma Intraductal não Infiltrante/virologia , Infecções por Papillomavirus/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Alphapapillomavirus/genética , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , DNA Viral/isolamento & purificação , Feminino , Papillomavirus Humano 11/isolamento & purificação , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/isolamento & purificação , Papillomavirus Humano 6/isolamento & purificação , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Infecções por Papillomavirus/complicações , Reação em Cadeia da Polimerase , Medição de Risco , Fatores de Risco , Adulto Jovem
17.
ACS Omega ; 6(4): 2434-2442, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33553861

RESUMO

Petroleum-based plastics commonly and widely used on a daily basis are a threat to ecological health as they do not degrade in an ecologically feasible time frame. A class of natural polymers known as polyhydroxyalkanoates (PHAs) represents an up-and-coming alternative to petroleum-based materials, as they share properties similar to those of commodity plastics, such as polyethylene, polystyrene, among others, with the advantage of being biodegradable. PHAs are naturally produced by microorganisms under stress, and various farming practices have been proposed to be used for the synergistic and sustainable production of PHA for commercial purposes. Aquaculture has demonstrated particular potential for the production of PHA; however, a large struggle in commercializing these polymers is in procuring necessary feedstocks for manufacture outside of the laboratory environment. Through the coupling of PHA production and biofloc technology in aquaculture, the impediments to commercial exploitation can be potentially surmounted, while also providing for higher production efficiency in aquafarms. This mini-review covers the basic aspects of biofloc technology applied to aquaculture for the commercial production of PHA in large scale and offers a brief perspective on the next steps associated with the research and implementation of PHA production with biofloc technology.

18.
J Ethnobiol Ethnomed ; 17(1): 16, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33752732

RESUMO

BACKGROUND: Copernicia prunifera belongs to the Arecaceae family, and its production chain includes a set of economic activities based on the use of the stipe, petiole, fiber, fruits, roots, and leaves from which carnaúba wax is extracted, an economically valuable resource in the region. This study aimed to evaluate the uses, management, and perception of the species by local extractors. METHODS: Two communities were studied, Bem Quer, where 15 extractors of carnaúba leaves were interviewed, and Cana, where 21 extractors considered specialists were interviewed, totaling a sample of 36 interviewees. Interviewees were asked questions about uses, ways of handling, and perception of morphological variation in the carnaúba leaves. The number of leaves extracted and the income obtained from the sale of leaves were estimated from interviews and notes that each leader of extractors held during the year of the research and previous years, as well as direct observations made by researchers in the communities which recollection area of straw hold about 80 thousand individuals of C. prunifera. A regression analysis was used to explore the relationships between social variables (age, time in extractive activity, and income obtained from extraction) with the number of leaves exploited. RESULTS: The leaf was indicated as the most used part, from which an important powder is extracted for the production of wax. In addition, the leaf was also indicated to be used for fertilization and construction. The relationship between the socioeconomic variables, income from extraction, and the number of leaves extracted (in thousands) was significant (R2 = 0.73 and p < 0.001). However, the other variables analyzed in this study, such as the time spent extracting leaves and the years of residence in the community (R2 = 0.03 and p > 0.05); the number of leaves extracted and interviewee age (R2= 0.05 and p > 0.05); and the number of leaves extracted and extraction time (R2 = 0.04 and p > 0.05) did not indicate a relationship. CONCLUSION: Local extractors observed that new leaves have the highest sales value, as they have the highest production of powder. In addition, economic factor is the preponderant force that directs the management strategies of native species. For this species, however, morphological and genetic studies are needed for further clarification.


Assuntos
Arecaceae , Ceras , Brasil , Humanos , Folhas de Planta , População Rural , Ceras/economia
19.
PLoS One ; 16(8): e0256677, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34449827

RESUMO

Baryancistrus xanthellus (Loricariidae) is an endemic fish species from the Xingu River basin with its life history in the shallow rapid waters flowing over bedrock substrates. In order to investigate the genetic diversity and demographic history of B. xanthellus we analyzed sequence data for one mitochondrial gene (Cyt b) and introns 1 and 5 of nuclear genes Prolactin (Prl) and Ribosomal Protein L3 (RPL3). The analyses contain 358 specimens of B. xanthellus from 39 localities distributed throughout its range. The number of genetically diverged groups was estimated using Bayesian inference on Cyt b haplotypes. Haplotype networks, AMOVA and pairwise fixation index was used to evaluate population structure and gene flow. Historical demography was inferred through neutrality tests and the Extended Bayesian Skyline Plot (EBSP) method. Five longitudinally distributed Cyt b haplogroups for B. xanthellus were identified in the Xingu River and its major tributaries, the Bacajá and Iriri. The demographic analysis suggests that rapids habitats have expanded in the Iriri and Lower Xingu rivers since 200 ka (thousand years) ago. This expansion is possibly related to an increase in water discharge as a consequence of higher rainfall across eastern Amazonia. Conversely, this climate shift also would have promoted zones of sediment trapping and reduction of rocky habitats in the Xingu River channel upstream of the Iriri River mouth. Populations of B. xanthellus showed strong genetic structure along the free-flowing river channels of the Xingu and its major tributaries, the Bacajá and Iriri. The recent impoundment of the Middle Xingu channel for the Belo Monte hydroelectric dam may isolate populations at the downstream limit of the species distribution. Therefore, future conservation plans must consider the genetic diversity of B. xanthellus throughout its range.


Assuntos
Peixes-Gato/genética , Variação Genética/genética , Filogeografia , Proteína Ribossômica L3/genética , Animais , Brasil , Fluxo Gênico/genética , Genes Mitocondriais/genética , Haplótipos
20.
Diagnostics (Basel) ; 10(1)2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31936598

RESUMO

Cellular angiofibroma is a rare benign mesenchymal neoplasm most commonly occurring in the vulvovaginal region in women and the inguinoscrotal region in men with specific genetic deletion involved in the RB1 gene in chromosome 13q14 region. Atypical cellular angiofibroma and cellular angiofibroma with sarcomatous transformation are recently described variants showing worrisome morphological features and strong, diffuse p16 expression. Nevertheless, the molecular profile of these tumor entities is largely unknown. We carried out a next generation sequencing (NGS) study from six cases of atypical cellular angiofibroma and cellular angiofibroma with sarcomatous transformation. We were able to identify oncogenic TP53 gene mutations (33%) which may contribute to pathogenesis also resulting in p16 overexpression. In addition, RB1 gene alterations generally present were identified. Since it is a recently described and rare entity, the whole molecular signaling pathway is still largely obscured and the analysis of larger cohorts is needed to elucidate this issue.

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