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2.
Biota Neotrop. (Online, Ed. ingl.) ; 24(2): e20231560, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1564053

RESUMO

Abstract The Ibitipoca Mountains occur in southeastern Minas Gerais state, Southeast Brazil, and includes a mosaic of different vegetation types, as part of the Atlantic Forest domain. Such heterogeneity results in the occurrence of several ecotones in the region, considered essential buffer zones for maintaining biodiversity and structure among adjacent ecosystems. Given the importance of these environments for biodiversity conservation, floristic surveys are important to catalogue plant richness in natural areas, where species and landscapes have been destroyed, especially over the last decades. To contribute to increase the knowledge on the vascular Flora in the Ibitipoca Mountains, a floristic inventory was undertaken in private properties located in the boundaries of "Parque Estadual do Ibitipoca" (Ibitipoca State Park). Relevant findings of the present study include: characterization of the different vegetation types, 17 new records for the Flora of Minas Gerais, collection of 288 species never recorded in the state park (80% dissimilarity - especially due to the occurrence and size of different phytophysiognomies between these areas) and presence of 31 threatened species. In addition, discussions about conservation efforts and public policies are presented.


Resumo A Serra do Ibitipoca ocorre no sudeste do estado de Minas Gerais, sudeste do Brasil, e inclui um mosaico de diferentes tipos de vegetação, como parte do domínio da Mata Atlântica. Tal heterogeneidade é resultado da ocorrência de diversos ecótonos na região, considerados áreas de amortecimento essenciais para manutenção da biodiversidade e estrutura de ecossistemas adjacentes. Dada a importância destes ambientes para conservação da biodiversidade, inventários florísticos são importantes para catalogar a riqueza de plantas em áreas naturais, onde espécies e paisagens têm sido destruídas, especialmente nas últimas décadas. Para contribuir com o aumento do conhecimento sobre a Flora vascular na Serra do Ibitipoca, um inventário florístico foi conduzido em áreas privadas adjacentes ao Parque Estadual do Ibitipoca. As descobertas mais relevantes do presente estudo incluem: caracterização dos diferentes tipos de vegetação, 17 novos registros para a Flora de Minas Gerais, coleta de 288 espécies nunca registradas para o parque (80% de dissimilaridade - especialmente devido à ocorrência e tamanho de diferentes fitofisionomias entre as áreas) e presença de 31 espécies ameaçadas. Além disso, discussões sobre esforços para conservação e políticas públicas são apresentadas.

3.
ACS Omega ; 8(42): 39535-39545, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37901565

RESUMO

Herein, we describe a urea hydrogen peroxide-mediated sustainable protocol for the synthesis of selenylated imidazo[2,1-b]thiazole by using half molar equivalent diorganyl diselenides in ethyl lactate as a greener solvent. The reaction features high yields, easy performance on gram scale, metal-free conditions, as well as applicability to imidazopyridine and imidazopyrimidine.

4.
Sci Rep ; 13(1): 14251, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37652946

RESUMO

In this paper, we report an eco-friendly approach for the C(sp2)-H bond selenylation of imidazopyridines and other N-heteroarenes as well as simple arenes at ambient temperature. This new protocol consists of the reaction between (N-hetero)-arenes and the diorganyl-diselenides and trichloroisocyanuric acid (TCCA)-ethanol reagent system. In a short reaction time, the desired selenylated products were obtained regioselectively in good yields, with tolerance for a wide range of functional groups.

5.
Curr Biol ; 33(16): 3495-3504.e4, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37473761

RESUMO

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%-18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost.


Assuntos
Biodiversidade , Florestas , Humanos , Floresta Úmida , Brasil , Clima Tropical , Conservação dos Recursos Naturais , Ecossistema
6.
Oecologia ; 197(1): 243-257, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34370096

RESUMO

The diversity of endotherms and ectotherms may be differently affected by ambient temperature and net primary productivity (NPP). Additionally, little is known about how these drivers affect the diversity of guilds of different trophic levels. We assessed the relative role of temperature and NPP in multitrophic guilds of ectothermic (arthropods: ants, ground beetles, spiders, and harvestmen) and endothermic (large mammals) animals along a tropical elevational gradient. We sampled arthropods at eight elevation belts and large mammals at 14 elevation belts in Atlantic rainforest (ranging from 600 to 2450 m.a.s.l.) of Itatiaia National Park, Southeast Brazil. Overall arthropod species richness was more associated with temperature than overall large-mammal species richness, while the latter was more associated with NPP. When separated into trophic guilds, we found that the species richness associated with NPP increased across arthropod trophic levels from herbivores to predators. Conversely, although NPP influenced large-mammal herbivore species richness, its effects did not seem to accumulate across large-mammal trophic levels since the species richness of large-mammal omnivores was more associated with temperature and none of the variables we studied influenced large-mammal predators. We suggest that thermal physiological differences between ectotherms and endotherms are responsible for the way in which arthropods and large mammals interact with or are constrained by the environment. Furthermore, the inconsistency regarding the role of temperature and NPP on species richness across multitrophic guilds of ectotherms and endotherms could indicate that thermal physiological differences might also interfere with energy use and flux in the food web.


Assuntos
Artrópodes , Biodiversidade , Animais , Ecossistema , Herbivoria , Temperatura
7.
Proc Biol Sci ; 288(1951): 20210094, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-34004131

RESUMO

While the climate and human-induced forest degradation is increasing in the Amazon, fire impacts on forest dynamics remain understudied in the wetter regions of the basin, which are susceptible to large wildfires only during extreme droughts. To address this gap, we installed burned and unburned plots immediately after a wildfire in the northern Purus-Madeira (Central Amazon) during the 2015 El-Niño. We measured all individuals with diameter of 10 cm or more at breast height and conducted recensuses to track the demographic drivers of biomass change over 3 years. We also assessed how stem-level growth and mortality were influenced by fire intensity (proxied by char height) and tree morphological traits (size and wood density). Overall, the burned forest lost 27.3% of stem density and 12.8% of biomass, concentrated in small and medium trees. Mortality drove these losses in the first 2 years and recruitment decreased in the third year. The fire increased growth in lower wood density and larger sized trees, while char height had transitory strong effects increasing tree mortality. Our findings suggest that fire impacts are weaker in the wetter Amazon. Here, trees of greater sizes and higher wood densities may confer a margin of fire resistance; however, this may not extend to higher intensity fires arising from climate change.


Assuntos
Incêndios , Incêndios Florestais , Secas , Florestas , Humanos , Árvores
8.
Oecologia, v. 197, p 243-257, set. 2021
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3921

RESUMO

The diversity of endotherms and ectotherms may be differently affected by ambient temperature and net primary productivity (NPP). Additionally, little is known about how these drivers affect the diversity of guilds of different trophic levels. We assessed the relative role of temperature and NPP in multitrophic guilds of ectothermic (arthropods: ants, ground beetles, spiders, and harvestmen) and endothermic (large mammals) animals along a tropical elevational gradient. We sampled arthropods at eight elevation belts and large mammals at 14 elevation belts in Atlantic rainforest (ranging from 600 to 2450 m.a.s.l.) of Itatiaia National Park, Southeast Brazil. Overall arthropod species richness was more associated with temperature than overall large-mammal species richness, while the latter was more associated with NPP. When separated into trophic guilds, we found that the species richness associated with NPP increased across arthropod trophic levels from herbivores to predators. Conversely, although NPP influenced large-mammal herbivore species richness, its effects did not seem to accumulate across large-mammal trophic levels since the species richness of large-mammal omnivores was more associated with temperature and none of the variables we studied influenced large-mammal predators. We suggest that thermal physiological differences between ectotherms and endotherms are responsible for the way in which arthropods and large mammals interact with or are constrained by the environment. Furthermore, the inconsistency regarding the role of temperature and NPP on species richness across multitrophic guilds of ectotherms and endotherms could indicate that thermal physiological differences might also interfere with energy use and flux in the food web.

9.
An Acad Bras Cienc ; 92(3): e20200263, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33175016

RESUMO

The main purpose of this paper was to present the Forestry Routing Optimization Model (FRoM) as a version of the classical Vehicle Routing Problem (VRP). This work approaches for wood logistic problems consisting of simple displacement and multiple displacements of trucks toward the stands. The FRoM encompasses both steps into one single integer mixed linear programming model, considering cranes and trucks schedule, fleet reduction, reduction of overtime, reduction of half-load transportation, and approaching the minimum distance traveled along a fixed planning horizon. Some technique constraints were implemented to provide accurate model function. An executed real problem data was used to compare the outcomes. The objective was to carry and transport 21,881.82 tons of lumber from 10 stands using a total of 48 trucks and 5 cranes in a planning horizon of 6 days, which each day has 20 hours of effective work. The FRoM has performed a fleet reduction of 72.92%, eliminating overtime. It has reduced the half-load trips to the order of 3.17% of all routes. The crane's analysis allowed catching points of inefficiency due to operational idleness. The FRoM provided savings of 49.12% at all logistic costs. FRoM has shown to be a good option as a route optimizer for forestry logistics.


Assuntos
Agricultura Florestal , Madeira , Meios de Transporte
10.
Trop Anim Health Prod ; 52(6): 3527-3535, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32960398

RESUMO

Palicourea marcgravii is the most important poisonous plant of cattle in Brazil. It contains monofluoroacetic acid and causes sudden death associated with exercise. Herein, we describe the temporal and spatial distribution of the toxic disease. The survey was based on the epidemiological, clinical, and pathological data of the Setor de Anatomia Patológica (SAP) of the Universidade Federal Rural do Rio de Janeiro (UFRuralRJ) to report outbreaks of poisoning by P. marcgravii, from 1953 to 2018. Clinical signs were peracute and included labored breathing, loss of balance, muscle tremors, lateral recumbency, and limb paddling. Gross lesions such as congestion of large vessels and edema and pulmonary congestion were observed. Multifocal areas of vacuolar hydropic degeneration of distal contorted tubule cells with nuclear pyknosis were observed in the kidneys. The plant is found in forests, and the poisoning occurs mainly after clearing forests for pasture, in areas of natural forest recovery called "capoeira," which provide a favorable environment for maintaining P. marcgravii growth. Outbreaks of P. marcgravii poisoning coincided with periods of creation of large deforested pastures in the Southeast and Midwest regions of Brazil, and the poisoning should be considered an additional risk after deforestation. The most effective prophylaxis is fencing off the forest areas that contain these plants.


Assuntos
Doenças dos Bovinos/etiologia , Intoxicação por Plantas/veterinária , Rubiaceae/química , Animais , Brasil , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/terapia , Intoxicação por Plantas/diagnóstico , Intoxicação por Plantas/etiologia , Intoxicação por Plantas/terapia , Plantas Tóxicas/química
11.
Front Oncol ; 10: 825, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32509587

RESUMO

Purpose: To evaluate the role of diffusion-weighted magnetic resonance imaging (DW-MRI) in the assessment of therapeutic response in patients with choroidal melanoma treated with brachytherapy. Materials and Methods: We performed a prospective, unicentric study which included patients with choroidal melanoma and indication for brachytherapy. Three DW-MRI examinations were proposed for each patient, one before and two after treatment. The apparent diffusion coefficient (ADC) value was calculated on DW-MRI and compared with local tumor control assessed by ophthalmologic follow-up. Results: From 07/2018 to 06/2019, 19 patients were recruited, 13 of whom underwent follow-up examinations. Patients' ages ranged from 24 to 78 years and 52.9% were male. At the ocular ultrasound, the mean tumor thickness and diameter were 6.3 and 11.5 mm, respectively. Two patients (15.4%) showed signs of tumor progression during follow-up (7 and 9 months after treatment). There was no statistically significant difference in tumor size between MR before and after treatment, however, there was a significant reduction in mean ADC in patients with progression (p = 0.02). Conclusion: DW-MRI is a promising method for monitoring patients with choroidal melanoma; reduction in the mean ADC values between pre-treatment MRI and the first post-treatment MRI may be related to the lack of response to brachytherapy and increased risk of disease progression.

12.
Appl Spectrosc ; 74(7): 758-766, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32419472

RESUMO

Burns are one of the leading causes of morbidity worldwide and the most costly traumatic injuries. A better understanding of the molecular mechanisms in wound healing is required to accelerate tissue recovery and reduce the health economic impact. However, the standard techniques used to evaluate the biological events associated to wound repair are laborious, time-consuming, and/or require multiple assays/staining. Therefore, this study aims to evaluate the feasibility of Fourier transform infrared (FT-IR) spectroscopy to monitor the progress and healing status of burn wounds. Burn injuries were induced on Wistar rats by water vapor exposure and biopsied for further histopathological and spectroscopic evaluation at four time-points (3, 7, 14, and 21 days). Spectral data were preprocessed and compared by principal component analysis. Pairwise comparison of post-burn groups to each other revealed that metabolic activity induced by thermal injury decreases as the healing progresses. Higher amounts of carbohydrates, proteins, lipids, and nucleic acids were evidenced on days 3 and 7 compared to healthy skin and reduced amounts of these molecular structural units on days 14 and 21 post-burn. FT-IR spectroscopy was used to determine the healing status of a wound based on the biochemical information retained by spectral signatures in each phase of healing. Our findings demonstrate that FT-IR spectroscopy can monitor the biological events triggered by burn trauma as well as to detect the wound status including full recovery based on the spectral changes associated to the biochemical events in each phase.


Assuntos
Queimaduras/terapia , Pele/lesões , Cicatrização , Animais , Queimaduras/diagnóstico por imagem , Raios Infravermelhos , Ratos Wistar , Análise Espectral
13.
J Econ Entomol ; 113(1): 482-488, 2020 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-31612227

RESUMO

The Tibraca limbativentris is a pest that causes rice crop damage and may lead to grain yield reductions of up to 90%. The most commonly used tactic for T. limbativentris control is chemical, which causes adverse effects on the environment. This study was conducted to identify sources of antixenosis and antibiosis resistance to T. limbativentris mediated by the hardness and diameter of the stem of the rice plant. Antibiosis and antixenosis tests were carried out with 22 rice genotypes of Brazilian and Asian origin. The Canela de Ferro, BRS Esmeralda, and Desconhecido Branco genotypes had the lowest proportions of stems showing symptoms of the damage caused by T. limbativentris. Canela de Ferro, Primavera, and IR 22 genotypes had the lowest nymphs survivorship and the genotypes Marabá Branco, Marabá, Skirivimankoti, Pepita, BR IRGA 409, Curinga, IR 40, Bonança, Desconhecido Branco, Bico Ganga, Primavera, and BRS Esmeralda were the least attractive to the insects. The genotypes BRS Esmeralda, Primavera, Desconhecido Branco, and Canela de Ferro were resistant to the rice stalk stink bug by antibiosis and/or antixenosis. These genotypes can be used directly by rice farmers for T. limbativentris management. Molecular biology studies should be conducted to identify and characterize resistance genes in these genotypes so that they can be used in breeding programs.


Assuntos
Hemípteros , Heterópteros , Oryza , Animais , Brasil , Genótipo , Ninfa
14.
Zootaxa ; 4496(1): 517-534, 2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-30313720

RESUMO

Earthworm populations often increase with the adoption of no-tillage (NT) practices, but few studies have evaluated earthworm diversity in these agroecosystems. In the present study we assessed earthworm species richness in 40 sites under NT and six native Atlantic forest fragments in Western Paraná, Southern Brazil. At each site earthworms were sampled quantitatively (n=5) and qualitatively (n=5), by handsorting soil monoliths (20 x 20 cm width x 20 cm depth), totaling 460 samples overall. Earthworms were killed and fixed in 96% ethanol, counted and identified. Overall, 18 species were found, in the families Acanthodrilidae, Glossoscolecidae, Megascolecidae, Rhinodrilidae and Ocnerodrilidae, of which 10 were native and eight exotic. No-tillage agroecosystems had larger earthworm populations and higher species richness overall than native forests, although this was mainly due to colonization of these agricultural fields by exotic species. Mostly native species were found in the Atlantic forests, highlighting the importance of these habitats as refugia for native earthworm species conservation.


Assuntos
Oligoquetos , Animais , Brasil , Florestas , Solo
15.
16.
PLoS One ; 11(11): e0167292, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27902787

RESUMO

Animal pollinators contribute to human food production and security thereby ensuring an important component of human well-being. The recent decline of these agents in Europe and North America has aroused the concern of a potential global pollinator crisis. In order to prioritize efforts for pollinator conservation, we evaluated the extent to which food production depends on animal pollinators in Brazil-one of the world's agriculture leaders-by comparing cultivated area, produced volume and yield value of major food crops that are pollinator dependent with those that are pollinator non-dependent. In addition, we valued the ecosystem service of pollination based on the degree of pollinator dependence of each crop and the consequence of a decline in food production to the Brazilian Gross Domestic Product and Brazilian food security. A total of 68% of the 53 major food crops in Brazil depend to some degree on animals for pollination. Pollinator non-dependent crops produce a greater volume of food, mainly because of the high production of sugarcane, but the cultivated area and monetary value of pollinator dependent crops are higher (59% of total cultivated area and 68% of monetary value). The loss of pollination services for 29 of the major food crops would reduce production by 16.55-51 million tons, which would amount to 4.86-14.56 billion dollars/year, and reduce the agricultural contribution to the Brazilian GDP by 6.46%- 19.36%. These impacts would be largely absorbed by family farmers, which represent 74.4% of the agricultural labor force in Brazil. The main effects of a pollinator crisis in Brazil would be felt by the poorer and more rural classes due to their lower income and direct or exclusive dependence on this ecosystem service.


Assuntos
Conservação dos Recursos Naturais , Produtos Agrícolas/fisiologia , Polinização , Animais , Brasil , Abastecimento de Alimentos
17.
PLoS One ; 11(4): e0153827, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27099925

RESUMO

Mollisols of Santa Fe have different tilth and load support capacity. Despite the importance of these attributes to achieve a sustainable crop production, few information is available. The objectives of this study are i) to assess soil physical indicators related to plant growth and to soil mechanical behavior; and ii) to establish relationships to estimate the impact of soil loading on the soil quality to plant growth. The study was carried out on Argiudolls and Hapludolls of Santa Fe. Soil samples were collected to determine texture, organic matter content, bulk density, water retention curve, soil resistance to penetration, least limiting water range, critical bulk density for plant growth, compression index, pre-consolidation pressure and soil compressibility. Water retention curve and soil resistance to penetration were linearly and significantly related to clay and organic matter (R2 = 0.91 and R2 = 0.84). The pedotransfer functions of water retention curve and soil resistance to penetration allowed the estimation of the least limiting water range and critical bulk density for plant growth. A significant nonlinear relationship was found between critical bulk density for plant growth and clay content (R2 = 0.98). Compression index was significantly related to bulk density, water content, organic matter and clay plus silt content (R2 = 0.77). Pre-consolidation pressure was significantly related to organic matter, clay and water content (R2 = 0.77). Soil compressibility was significantly related to initial soil bulk density, clay and water content. A nonlinear and significantly pedotransfer function (R2 = 0.88) was developed to predict the maximum acceptable pressure to be applied during tillage operations by introducing critical bulk density for plant growth in the compression model. The developed pedotransfer function provides a useful tool to link the mechanical behavior and tilth of the soils studied.


Assuntos
Solo/química , Agricultura/métodos , Silicatos de Alumínio/química , Argentina , Argila , Plantas/química , Água/química
18.
PLoS One ; 11(3): e0150860, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26938642

RESUMO

Increasing demand for biofuel has intensified land-use change (LUC) for sugarcane (Saccharum officinarum) expansion in Brazil. Assessments of soil quality (SQ) response to this LUC are essential for quantifying and monitoring sustainability of sugarcane production over time. Since there is not a universal methodology for assessing SQ, we conducted a field-study at three sites within the largest sugarcane-producing region of Brazil to develop a SQ index (SQI). The most common LUC scenario (i.e., native vegetation to pasture to sugarcane) was evaluated using six SQI strategies with varying complexities. Thirty eight soil indicators were included in the total dataset. Two minimum datasets were selected: one using principal component analysis (7 indicators) and the other based on expert opinion (5 indicators). Non-linear scoring curves were used to interpret the indicator values. Weighted and non-weighted additive methods were used to combine individual indicator scores into an overall SQI. Long-term conversion from native vegetation to extensive pasture significantly decreased overall SQ. In contrast, conversion from pasture to sugarcane had no significant impact on overall SQ at the regional scale, but site-specific responses were found. In general, sugarcane production improved chemical attributes (i.e., higher macronutrient levels and lower soil acidity); however it has negative effects on physical and biological attributes (i.e., higher soil compaction and structural degradation as well as lower soil organic carbon (SOC), abundance and diversity of macrofauna and microbial activity). Overall, we found that simple, user-friendly strategies were as effective as more complex ones for identifying SQ changes. Therefore, as a protocol for SQ assessments in Brazilian sugarcane areas, we recommend using a small number of indicators (e.g., pH, P, K, Visual Evaluation of Soil Structure -VESS scores and SOC concentration) and proportional weighting to reflect chemical, physical and biological processes within the soil. Our SQ evaluations also suggest that current approaches for expanding Brazilian sugarcane production by converting degraded pasture land to cropland can be a sustainable strategy for meeting increasing biofuel demand. However, management practices that alleviate negative impacts on soil physical and biological indicators must be prioritized within sugarcane producing areas to prevent unintentional SQ degradation over time.


Assuntos
Agricultura/métodos , Saccharum/crescimento & desenvolvimento , Solo/química , Algoritmos , Biocombustíveis , Brasil , Análise Custo-Benefício , Ecossistema , Monitoramento Ambiental , Geografia , Concentração de Íons de Hidrogênio , Modelos Estatísticos , Dinâmica não Linear , Análise de Componente Principal
19.
Lasers Surg Med ; 48(5): 538-45, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26899946

RESUMO

BACKGROUND AND OBJECTIVE: Vibrational spectroscopic methods associated with multivariate statistical techniques have been succeeded in discriminating skin lesions from normal tissues. However, there is no study exploring the potential of these techniques to assess the alterations promoted by photodynamic effect in tissue. The present study aims to demonstrate the ability of Fourier Transform Infrared (FTIR) spectroscopy on Attenuated total reflection (ATR) sampling mode associated with principal component-linear discriminant analysis (PC-LDA) to evaluate the biochemical changes caused by photodynamic therapy (PDT) in skin neoplastic tissue. MATERIALS AND METHODS: Cutaneous neoplastic lesions, precursors of squamous cell carcinoma (SCC), were chemically induced in Swiss mice and submitted to a single session of 5-aminolevulinic acid (ALA)-mediated PDT. Tissue sections with 5 µm thickness were obtained from formalin-fixed paraffin-embedded (FFPE) and processed prior to the histopathological analysis and spectroscopic measurements. Spectra were collected in mid-infrared region using a FTIR spectrometer on ATR sampling mode. Principal Component-Linear Discriminant Analysis (PC-LDA) was applied on preprocessed second derivatives spectra. Biochemical changes were assessed using PCA-loadings and accuracy of classification was obtained from PC-LDA . RESULTS: Sub-bands of Amide I (1,624 and 1,650 cm(-1) ) and Amide II (1,517 cm(-1) ) indicated a protein overexpression in non-treated and post-PDT neoplastic tissue compared with healthy skin, as well as a decrease in collagen fibers (1,204, 1,236, 1,282, and 1,338 cm(-1) ) and glycogen (1,028, 1,082, and 1,151 cm(-1) ) content. Photosensitized neoplastic tissue revealed shifted peak position and decreased ß-sheet secondary structure of proteins (1,624 cm(-1) ) amount in comparison to non-treated neoplastic lesions. PC-LDA score plots discriminated non-treated neoplastic skin spectra from post-PDT cutaneous lesions with accuracy of 92.8%, whereas non-treated neoplastic skin was discriminated from healthy tissue with 93.5% accuracy and post-PDT cutaneous lesions was discriminated from healthy tissue with 89.7% accuracy. CONCLUSION: PC-LDA was able to discriminate ATR-FTIR spectra of non-treated and post-PDT neoplastic lesions, as well as from healthy skin. Thus, the method can be used for early diagnosis of premalignant skin lesions, as well as to evaluate the response to photodynamic treatment. Lasers Surg. Med. 48:538-545, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Ácido Aminolevulínico/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Neoplasias Cutâneas/tratamento farmacológico , Pele/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Ácido Aminolevulínico/uso terapêutico , Animais , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Análise Discriminante , Feminino , Camundongos , Fármacos Fotossensibilizantes/uso terapêutico , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/tratamento farmacológico , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia , Análise de Componente Principal , Pele/metabolismo , Pele/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
20.
Zootaxa ; 4034(1): 161-81, 2015 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-26624436

RESUMO

Comprising 56 species, Timea Gray, 1867 belongs to the monotypic family Timeidae Gray, 1867, with both family and genus characterized by the presence of (sub)tylostyles as megascleres, and euasters as microscleres. Two new species are described from the coast of Rio de Janeiro state, Timea berlincki sp. nov. and Timea clandestina sp. nov., the first of which also from São Paulo state (southeastern Brazil). Both are compared to other species based on their morphological and skeletal characters. Records of all species of the genus worldwide are tabulated and discussed, and an identification key for Tropical western Atlantic species of Timea is offered.


Assuntos
Poríferos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Tamanho do Órgão , Poríferos/anatomia & histologia , Poríferos/crescimento & desenvolvimento
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