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1.
J Nematol ; 54(1): 20220057, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36742266

RESUMO

Pratylenchus is one of the most limiting nematodes of Musaceae production in the world. Knowledge of the nematode species is one of the requirements for its management in the field. This study aimed to identify up to the species level Pratylenchus populations associated with plantain and banana crops in the states of Caldas, Quindío, and Valle del Cauca in Colombia. In these regions, Pratylenchus has been reported to affect these crops in the past, but with records of the nematode only up to the genus level. For this purpose, five populations of Pratylenchus extracted from samples composed of roots and rhizospheric soil, four from plantain and one from banana, were identified through morphological, morphometric, and molecular analysis (sequencing of the D2-D3 of rRNA and cytochrome oxidase subunit I of mtDNA). All populations were identified as P. araucensis, a species reported previously in eastern Colombia, and one that the present study found in the center and southwest of the country, indicating that this species of nematode is widely distributed in the Musaceae-producing areas of Colombia. The present study reports the first COI mtDNA sequences for this species of nematode.

2.
Helminthologia ; 58(1): 74-84, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33664620

RESUMO

Aphelenchoides pseudogoodeyi has recently been reported in association with seeds of forage grasses and rice in Brazil and senescent strawberry plants, in the United States. This nematode is likely a mycophagous species; however, so far, its pathogenicity potential to plants is unclear. This study aimed to verify the pathogenicity of A. pseudogoodeyi to two species of ornamental plants. The experiments were conducted by inoculating A. pseudogoodeyi onto Bird's-Nest Fern (Asplenium nidus) and Oriental Lily (Lilium speciosum) leaves, using two inoculation methods (with and without injury). After 40 days of inoculation (DAI) in Bird's-Nest Fern and 5, 10, 20 and 40 DAI in Oriental Lily, the pathogenicity and the host efficiency were evaluated by symptoms observation and by severity, final nematode population and reproductive factor (RF), respectively. Additionally, a histopathological study was performed by inoculating A. pseudogoodeyi onto Bird's-Nest Fern for observing anatomical alterations. A. pseudogoodeyi was able to cause local necrotic lesions on both Bird's-Nest Fern and Oriental Lily leaves. However, the presence of injury was essential to enable A. pseudogoodeyi to penetrate and cause those symptoms in both plant species. Also, the total population of A. pseudogoodeyi decreased drastically over time and RF was <1, which characterized these species as poor-host or resistant plants. A. pseudogoodeyi penetrated into the foliar tissue and induced a total destruction of the mesophyll and collapse of the cells, with the formation of large intercellular spaces. It is concluded that A. pseudogoodeyi is an opportunistic pathogen as injury was required to induce symptoms in Bird's-Nest Fern and Oriental Lily.

3.
Helminthologia ; 58(2): 213-216, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34248382

RESUMO

Samples of black pepper root with the presence of galls from the most southern region of the State of Bahia, Brazil, were characterized biochemically and morphologically using three criteria: i) observation of the anterior region of the males; ii) analysis of female perineal configuration and iii) polyacrylamide gel electrophoresis technique. Meloidogyne arenaria was found. This is the first report of this pathosystem in the State.

4.
Helminthologia ; 57(1): 37-42, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32063738

RESUMO

Based on morphology, measurements of juveniles and female specimens and sequences of the D2/ D3 expansion 28S rDNA gene and ITS1 analysis by DNA barcode technique, a Xiphinema americanum group species associated with olive trees from state of Sao Paulo, Brazil was identifi ed as X. santos. This is the first report of X. santos in Southern Hemisphere and outside the European and African continents, thus extending its geographic range.

5.
Bull Entomol Res ; 108(1): 101-107, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28612699

RESUMO

The aim of this study was to verify the occurrence of the coffee berry borer, Hypothenemus hampei (Ferrari), and to evaluate the population fluctuation of the pest in the Brazilian Cerrado (Federal District). The study was conducted, between November 2014 and October 2015, at Embrapa Cerrados (Planaltina/DF, Brazil) in an irrigated conilon coffee production area. In November 2014, 120 samples (ten berries/sample) were collected from berries that had fallen on the ground from the previous harvest. Between November 2014 and October 2015, insects were collected weekly, using traps (polyethylene terephthalate bottles) baited with ethyl alcohol (98 GL), ethyl alcohol (98 GL) with coffee powder, or molasses. Between January and July 2015, samples were collected fortnightly from 92 plants (12 berries per plant). All samples were evaluated for the presence of adult coffee berry borers. Samples from the previous harvest had an attack incidence of 72.4%. The baited traps captured 4062 H. hampei adults, and showed no statistical difference in capture efficiency among the baits. Pest population peaked in the dry season, with the largest percentage of captured adults occurring in July (31.0%). An average of 18.6% of the collected berries was attacked by the borer and the highest percentage incidence was recorded in July (33.2%). Our results suggest that the coffee berry borer, if not properly managed, could constitute a limiting factor for conilon coffee production in the Brazilian Cerrado.


Assuntos
Coffea , Gorgulhos , Animais , Brasil , Dinâmica Populacional
6.
Zygote ; 26(1): 99-103, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29249213

RESUMO

The objective of this study was to assess the effects of bovine embryo vitrification by applying three different vitrification solutions containing ethylene glycol (EG) and dimethylsulphoxide (DMSO) at different concentrations (10, 20 or 25% each) combined with 1.0 M glucose or 1.0 M sucrose, on the in vitro hatching and expansion rates. Healthy oocytes were selected for in vitro maturation and fertilization from 200 bovine ovaries, and subsequently cultured up to the blastocyst stage (n = 800). Control (n = 200) and vitrified cells (n = 100 per treatment; 600 in total) were cultured for an extra 24 or 48 h to evaluate hatching and expansion, respectively. Vitrification significantly decreased embryonic re-expansion and hatching rates independently of the tested solution when compared with control embryos, but solutions with 25% EG + 25% DMSO resulted in the highest re-expansion (75%) and hatching (70%) rates, independently of the added sugar. The addition of sucrose resulted in higher rates of re-expanded and hatched embryos when compared with glucose addition. We concluded that the combination of 25% EG + 25% DMSO and 1.0 M sucrose allowed hatching and expansion of vitrified-warmed bovine embryos produced in vitro.


Assuntos
Blastocisto/fisiologia , Dimetil Sulfóxido/farmacologia , Etilenoglicol/farmacologia , Vitrificação , Animais , Bovinos , Crioprotetores/farmacologia , Feminino , Técnicas de Maturação in Vitro de Oócitos , Masculino
7.
Bull Entomol Res ; 107(5): 627-633, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28185606

RESUMO

This study aimed to monitor the population fluctuation of Cophes notaticeps (Marshall) (Coleoptera: Curculionidae) in a jatropha (Jatropha curcas L.) plantation in the Federal District, Brazil, through the use of a new trap, combined with different attractive lures and trap colors. The study was conducted at Embrapa Cerrados (Planaltina/DF) in a field trial with 720 plants. The new trap, named CPAC16, was made with PVC pipes (100 mm in diameter) of about 40 cm in length, with a window (8 × 10 cm2) in its center to enable insect access. A lure compartment was fixed on the inside of the trap`s top, and a pot, containing water and detergent, was placed at its bottom to collect the insects. The traps were painted in red, yellow, blue and green. Molasses, ethanol and pineapple were used as attractive lures. The traps were in the field trial area between May 2013 and April 2014 and the insects were collected weekly. The incidence of plants presenting damage caused by C. notaticeps was evaluated in the beginning and at the end of the study. The CPAC16 trap proved efficient in monitoring C. notaticeps. About 3494 of C. notaticeps adults were collected during the study. There were no significant differences among traps painted with different colors. The most attractive lure was molasses collecting 75.2% (n = 2627) of the specimens. Although the population peak occurred in December (n = 1162), C. notaticeps were collected throughout the year. The incidence of plants attacked by C. notaticeps ranged from 66.4% (start) to 100% (end).


Assuntos
Controle de Insetos/instrumentação , Gorgulhos , Animais , Brasil , Jatropha , Dinâmica Populacional
8.
Environ Manage ; 60(1): 157-164, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28271212

RESUMO

The presence of pharmaceuticals in the aquatic environment is a contemporary reality and it is necessary to understand more about the effects of this presence on organisms. The purpose of this work was to assess the ecotoxicity of antibiotics metronidazole, nitrofurantoin, trimethoprim, and sulphamethoxazole (single and mixture) in Vibrio fischeri and Desmodesmus subspicatus at µg L-1 concentrations. The evaluation of the toxic effect of the antibiotics on V. fischeri and D. subspicatus was based on fluorescence and bioluminescence tests, respectively, using nominal concentrations. When tested individually, the four antibiotics gave rise to a toxic effect on the evaluated organisms. Sulphamethoxazole caused a higher toxic effect on V. fischeri and D. subspicatus from 7.81 to 500 µg L-1. Trimethoprim and sulphamethoxazole showed hormesis for the concentrations, which ranged from 7.81 to 62.5 µg L-1. The mixture of antibiotics induced a toxic effect on the V. fischeri and D. subspicatus organisms (from 0.03 to 1 µg L-1 concentrations) than when the antibiotics were evaluated individually. These results were significant since water quality problems are widespread all over the word, and emerging pollutants such as antibiotics have been detected in the aquatic environment in very low concentrations.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Antibacterianos/toxicidade , Clorófitas/efeitos dos fármacos , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/toxicidade , Antibacterianos/análise , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Ecotoxicologia , Poluentes Químicos da Água/análise
9.
Osteoporos Int ; 26(2): 489-98, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25344400

RESUMO

SUMMARY: Age modifies the effect of area-level socioeconomic status (SES) in the risk of fragility hip fractures (HF). For older individuals, the risk of HF increases as SES increases. For younger individuals, risk of HF increases as SES decreases. Our study may help decision-makers to better direct the implementation of political decisions. INTRODUCTION: The effect of socioeconomic status (SES) on hip fracture (HF) incidence remains unclear. The objective of this study is to evaluate the association between HF incidence and municipality-level SES as well as interactions between age and SES. METHODS: From the Portuguese Hospital Discharge Database, we selected hospitalizations (2000-2010) of patients aged 50+, with HF diagnosis (codes 820.x, ICD9-CM), caused by traumas of low/moderate energy, excluding bone cancer cases and readmissions for aftercare. Municipalities were classified according to SES (deprived to affluent) using 2001 Census data. A spatial Bayesian hierarchical regression model (controlling for data heterogeneity and spatial autocorrelation), using the Poisson distribution, was used to quantify the relative risk (RR) of HF, 95% credible interval (95%CrI), and analyze the interaction between age and SES after adjusting for rural conditions. RESULTS: There were 96,905 HF, 77.3% of which were on women who, on average, were older than men (mean age 81.2±8.5 vs 78.2±10.1 years) at admission (p<0.001). In women, there was a lower risk associated with better SES: RR=0.83 (95%CrI 0.65-1.00) for affluent versus deprived. There was an inverse association between SES and HF incidence rate in the youngest and a direct association in the oldest, for both sexes, but significant only between deprived and affluent in older ages (≥75 years). CONCLUSIONS: Interaction between SES and age may be due to inequalities in lifestyles, access to health systems, and preventive actions. These results may help decision-makers to better understand the epidemiology of hip fractures and to better direct the available funding.


Assuntos
Fraturas do Quadril/epidemiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Portugal/epidemiologia , Características de Residência , Fatores de Risco , Classe Social
10.
Environ Monit Assess ; 187(6): 380, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26013655

RESUMO

In this work, particulate matter was collected using an active sampling system consisting of a PM10 (<10 µm) inlet coupled to a multifold device containing six channels, connected to a vacuum pump. Each channel was equipped with a filter holder fitted with adequately chosen filters. The system was fixed on a metallic structure, which was placed on the roof of the laboratory building, at the Faculty of Sciences, in Lisbon. Sampling took place under flow-controlled conditions. Aerosols were extracted from the filters with water, in defined conditions, and the water-soluble fraction was quantified by ion chromatography (IC) for the determination of inorganic anions (Cl(-), NO3 (-) and SO4 (2-)). Equivalent sampling through the various channels was validated. Validation was based on the metrological compatibility of the content results for the various filters. Ion masses are metrologically equivalent when their absolute difference is smaller than the respective expanded uncertainty. When this condition is verified, the studied multifold device produces equivalent samples.


Assuntos
Aerossóis/análise , Ânions/análise , Monitoramento Ambiental/instrumentação , Material Particulado/análise , Poluentes Atmosféricos/análise , Água/análise
11.
Photochem Photobiol Sci ; 13(9): 1253-60, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24977261

RESUMO

The oxidizing capacity and skin penetration of a commercial nanosized ZnO, Nanosun™ (Micronisers-Australia), were evaluated in vitro using porcine skin. Nanosun™ was initially characterized regarding its photo-reactivity and size distribution. An assay using methylene blue was performed to confirm the Nanosun™ photo-reactivity by exposing the labile molecule to UVA irradiation in the presence and absence of the nanosized ZnO. The nanosized ZnO was photo-reactive, reducing the methylene blue concentration to 7% while its concentration remained constant in the control formulation (without ZnO). The product label states that the average particle size is 30 nm. X-ray diffraction, nitrogen sorption and UV-spectrophotometry confirmed the presence of nanometric particles of approximately 30 nm. On the other hand, laser diffractometry showed micrometric particles in the size distribution profile. These analyses indicated that the nanoparticles are arranged as agglomerates and aggregates of micrometric proportions ranging from 0.6 to 60 µm. The skin lipid peroxidation was determined by the formation of thiobarbituric acid reactive species (TBARS) and quantified by UV-spectrophotometry. When exposed to UVA radiation the nanosized ZnO applied porcine skin showed a lower production of TBARS (7.2 ± 1.5 nmol g(-1)) than the controls, the MCT applied porcine skin (18.4 ± 2.8 nmol g(-1)) and the blank porcine skin (14.0 ± 2.0 nmol g(-1)). The penetration of ZnO nanoparticles was studied by scanning electron microscopy and energy dispersive X-ray spectroscopy. The tested ZnO particles did not penetrate into viable layers of the intact porcine skin. The particles tend to accumulate on the skin folds and in these regions they may penetrate into the horny layer.


Assuntos
Óxido de Zinco/química , Animais , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos da radiação , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Azul de Metileno/química , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Espectrometria por Raios X , Suínos , Raios Ultravioleta
12.
Genet Mol Res ; 12(3): 2712-24, 2013 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-23979896

RESUMO

Hymenaea courbaril L., popularly known as jatobá, is a plant species that grows in the forests of South America. The species has been used for culinary purposes and in folk medicine to treat arthritis and inflammations. Due to the increasing use of this plant globally, the present study aimed to evaluate the toxic, genotoxic, recombinogenic, and antigenotoxic effects of H. courbaril sap (Hycs) using the mouse bone marrow micronucleus test and the somatic mutation and recombination test (SMART) in Drosophila melanogaster. To evaluate the aneugenic and clastogenic activities revealed by the micronucleus test, the animals were treated with 3 doses of Hycs (5, 10, and 15 mL/kg body weight). To evaluate the antianeugenic and anticlastogenic activities, the animals were simultaneously treated with Hycs and mitomycin C (4 mg/kg body weight). To assess the mutagenic and recombinogenic activities using SMART, 3-day-old larvae derived from standard and high bioactivation crosses were treated with 3 doses of Hycs (3.0, 1.5, and 0.3 mL) for approximately 48 h. To evaluate antimutagenic and antirecombinogenic activities, larvae derived from both crosses were co-treated with 3 doses of Hycs (3.0, 1.5, and 0.3 mL) and doxorubicin (0.125 mg/ mL). The mouse bone marrow micronucleus test revealed that Hycs exhibited no cytotoxic, clastogenic and/or aneugenic effects, but did show anticytotoxic, anticlastogenic and/or antianeugenic activities. The SMART revealed no mutagenic or recombinogenic effects, but antimutagenic and antirecombinogenic activities were observed in somatic cells of D. melanogaster from both crosses.


Assuntos
Dano ao DNA , Hymenaea/química , Mutagênese/efeitos dos fármacos , Extratos Vegetais/toxicidade , Recombinação Genética/efeitos dos fármacos , Animais , Células da Medula Óssea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Drosophila melanogaster , Larva/efeitos dos fármacos , Camundongos , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Extratos Vegetais/farmacologia
13.
Exp Appl Acarol ; 60(3): 367-79, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23435931

RESUMO

Phytoseiulus macropilis Banks (Acari: Phytoseiidae) is an effective predator of tetranychid mites, but there are no data on its response to pesticides. We investigated the resistance of the predatory mite P. macropilis to the acaricides abamectin and dimethoate, and we examined the fitness costs associated with resistance. Two populations were tested: one from conventional cultivation and another from an area not commercially exploited. After the application of acaricides to the predator, we determined the lethal effects of the acaricides, the instantaneous rate of population increase (r(i)), the predation on Tetranychus urticae Koch (Acari: Tetranychidae) and its ability to locate prey in an olfactometer. P. macropilis exhibited resistance to dimethoate only. The low level of resistance (9.4x) of the predator did not affect their ability to locate prey. However, the dimethoate resistant population was not as effective in contatining prey population when in lower density and exhibited a more pronounced decrease of r(i) in the presence of this acaricide, due to the reduced oviposition of the predator, a likely consequence of the different genetic background of this population.


Assuntos
Dimetoato/toxicidade , Resistência a Medicamentos/genética , Inseticidas/toxicidade , Ácaros/efeitos dos fármacos , Comportamento Predatório/efeitos dos fármacos , Animais , Ácaros/genética , Controle Biológico de Vetores , Densidade Demográfica , Tetranychidae/fisiologia , Testes de Toxicidade
14.
Braz J Biol ; 83: e273470, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37851770

RESUMO

The performance of three successive generations of Mahanarva spectabilis (Distant) (Hemiptera: Cercopidae) fed on four forages exposed to environments with different CO2 concentrations was evaluated. In the first bioassay, we utilized the following scenarios: A) plants and insects were kept at high and constant CO2 (700 ppm) and B) the insects were kept at CO2 700 ppm and fed on plants from the greenhouse (average of 390 ppm). In the second bioassay, we utilized the following scenarios: C) plants and insects were kept in a greenhouse and D) the insects were kept in the greenhouse and fed on plants kept at CO2 700 ppm. The survival and duration of the nymphal and adult stages and the number of eggs/female of M. spectabilis were evaluated. It was only possible to evaluate the cumulative effects of the increase of CO2 on three successive generations of M. spectabilis kept in a greenhouse, due to the reduced survival of the insects in the first generation in the laboratory. A greater direct than indirect effect of the CO2 level on the performance of M. spectabilis was observed. Furthermore, it should be considered that the effect of CO2 elevation on the survival, periods of development, and fecundity, when taken together, can significantly impact the population dynamics of M. spectabilis in future climate scenarios.


Assuntos
Brachiaria , Hemípteros , Animais , Dióxido de Carbono , Ninfa , Clima
15.
Radiography (Lond) ; 29 Suppl 1: S117-S127, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36959043

RESUMO

INTRODUCTION: The role of the Therapy Radiographer/Radiation Therapist (TR/RTT) is to provide radiotherapy to patients with a cancer diagnosis. This includes, not only administration of treatment, but also management of side-effects and provision of support/care. Despite this role being consistent throughout Europe, there is currently no standardisation of education for TRs/RTTs. The SAFE EUROPE project aims to standardize TR/RTT education to enable 'safe and free exchange' of TRs/RTTs across Europe. Consequently, this study aims to explore patients' perspectives regarding the current skills and competencies of TRs/RTTs. METHODS: From May 2021 to February 2022, semi-structured interviews were conducted with patients who had recently received radiotherapy in the UK, Malta and Portugal. Ethical approval for this study was granted by the NHS Research Ethics Committee with additional local approvals obtained. RESULTS: Forty-eight participants from the UK (n = 18), Portugal (n = 19), and Malta (n = 11) completed interviews. Participants described high satisfaction with TRs'/RTTs' competence and skills in all three countries. The main theme arising from the analysis was the importance of trust building with TRs/RTTs. Six factors were identified as influencing levels of trust: communication; side-effect management; team consistency; relational skills; patient dignity; and competence. A small number of patients reported feeling rushed and not having their physical and emotional needs met by TRs/RTTs. CONCLUSION: This multicentre study demonstrated that patients perceive TRs/RTTs in the UK, Malta and Portugal as highly competent and skilled. Practical recommendations are provided to address identified deficits in practice, which can be addressed through adaptation of TR/RTT education/training and clinical practice. IMPLICATIONS FOR PRACTICE: Recommendations arising from this study are important to ensure that TRs/RTTs have transferable skills that provide consistently high quality care to patients throughout Europe.


Assuntos
Radioterapia (Especialidade) , Humanos , Portugal , Malta , Europa (Continente) , Reino Unido
16.
Arthritis Res Ther ; 24(1): 25, 2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-35039075

RESUMO

BACKGROUND: Intervertebral disc (IVD) herniation is characterized by annulus fibrosus failure (AF) in containing the nucleus pulposus (NP). IVD herniation involves cellular and extracellular matrix (ECM) alterations that have been associated with tissue fibrosis, although still poorly investigated. METHODS: Here, fibrotic alterations in human AF were evaluated, by characterizing the herniated ECM. Human AF samples (herniated lumbar IVD (n = 39, age 24-83) and scoliosis controls (n = 6, age 15-21)) were processed for transmission electron microscopy and histological/immunohistochemical analysis of fibrotic markers. Correlations between the fibrotic markers in AF ECM and the degree of NP containment (protused, contained and uncontained) and patients' age were conducted. RESULTS: Our results demonstrate that with herniation progression, i.e. loss of NP containment, human AF presents less stained area of sulphated glycosaminoglycans and collagen I, being collagen I fibres thinner and disorganized. On the other hand, fibronectin stained area and percentage of α-smooth muscle actin+ cells increase in human AF, while matrix metalloproteinase-12 (MMP12) production and percentage of macrophages (CD68+ cells) remain constant. These structural and biochemical fibrotic alterations observed in human AF with herniation progression occur independently of the age. CONCLUSIONS: The characterization of human AF here conducted evidence the presence of fibrosis in degenerated IVD, while highlighting the importance of considering the herniation progression stage, despite the patients' age, for a better understanding of the mechanisms behind AF failure and IVD herniation.


Assuntos
Anel Fibroso , Degeneração do Disco Intervertebral , Deslocamento do Disco Intervertebral , Disco Intervertebral , Anel Fibroso/patologia , Fibrose , Humanos , Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/patologia
17.
Chem Phys Lipids ; 234: 105018, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33232725

RESUMO

As a potential drug, 2-nitrobenzaldehyde-thiosemicarbazone (2-TSC), a thiosemicarbazone derived from the terpene R-(+)-limonene, was studied through calorimetric and spectroscopic techniques. Differential Scanning Calorimetry (DSC) data showed that 2-TSC causes structural changes in a 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DMPC) membrane, strongly decreasing the cooperativity of the bilayer gel-fluid thermal transition. Optical absorption spectroscopy showed that 2-TSC is more soluble in ethanol and lipids than in water medium, and that the drug displays different structures in the different environments. Though 2-TSC displays no fluorescence, time resolved fluorescence showed that the drug is an effective quencher of the fluorescent probe 6-dodecanoyl-2-dimethylaminonaphthalene (Laurdan). As it is well accepted that Laurdan is positioned into the bilayer close to the membrane surface, that is possibly the localization of 2-TSC in a bilayer. Electron spin resonance (ESR) of the probe 1-palmitoyl-2-stearoyl-(14-doxyl)-sn-glycero-3-phosphocholine (14-PCSL) revealed that 2-TSC is inserted into the hydrocarbon part of the bilayer, fluidizing the lipid bilayer gel phase and rigidifying or organizing the bilayer fluid phase. Similar effects are found for other lipophilic molecules, including cholesterol. These results are useful to improve the understanding of the processes that govern the interaction of thiosemicarbazones with cell membranes, related to the activity of the drugs and their cytotoxicity.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/análogos & derivados , Limoneno/química , 1,2-Dipalmitoilfosfatidilcolina/química , Varredura Diferencial de Calorimetria , Espectroscopia de Ressonância de Spin Eletrônica , Corantes Fluorescentes/química , Estrutura Molecular , Espectrometria de Fluorescência , Estereoisomerismo
18.
Sci Rep ; 10(1): 3732, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32099014

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

19.
Cell Mol Biol (Noisy-le-grand) ; 55(3): 29-33, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-20003809

RESUMO

The objective of this work is to develop procedures for internal monitoring of (18)F to be applied in cases of possible incorporation of fluoride and (18)FDG, using in vivo and in vitro methods of measurements. The Na I (Tl) 8" x 4" scintillation detector installed at IRD-Whole Body Counter was calibrated for measurements with a whole body anthropomorphic phantom, simulating homogeneous distribution of (18)F in the body. The NaI(Tl) 3"x 3" scintillation detector installed at the IRD-Whole Body Counter was calibrated for in vivo measurements with a brain phantom inserted in an artificial skull, simulating (18)FDG incorporation. The HPGe detection system installed at the IRD-Bioassay Laboratory was calibrated for in vitro measurements of urine samples with 1 liter plastic bottles containing a standard liquid source. A methodology for bioassay data interpretation, based on standard ICRP models edited with the software AIDE-version 6, was established. It is concluded that in vivo measurements have sufficient sensitivity for monitoring (18)F in the forms of fluoride and (18)FDG. The use of both in vitro and in vivo bioassay data can provide useful information for the interpretation of bioassay data in cases of accidental incorporation in order to identify the chemical form of (18)F incorporated.


Assuntos
Radioisótopos de Flúor/metabolismo , Fluordesoxiglucose F18/metabolismo , Exposição Ocupacional , Compostos Radiofarmacêuticos/metabolismo , Contagem Corporal Total , Brasil , Humanos , Imagens de Fantasmas , Contagem de Cintilação/instrumentação , Contagem de Cintilação/métodos , Contagem Corporal Total/instrumentação , Contagem Corporal Total/métodos
20.
J Oral Rehabil ; 36(1): 26-31, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18976263

RESUMO

The aim of this study was to assess the prevalence of condition-specific impacts on daily performances attributed to malocclusion in British adolescents. Two hundred 16- to 17-year-old adolescents were randomly selected from 957 children attending a public college in London, UK. During interviews, participants provided information about demographic variables and socio-dental impacts on quality of life attributed to malocclusions, using the Condition-Specific form of the Oral Impacts on Daily Performances (CS-OIDP) index. Adolescents were also clinically examined using the Index of Orthodontic Treatment Need. Statistical comparison by covariates was performed using chi-squared test and chi-squared test for trends. The prevalence of oral impacts on daily performances attributed to any oral condition was 26.5% whereas the prevalence of CS-OIDP attributed to malocclusion was 21.5%. There was no statistically significant difference by sex, age, ethnicity or orthodontic treatment status of schoolchildren in the prevalence of CS-OIDP attributed to malocclusion (P >/= 0.243 for all cases). However, there was a linear trend for the prevalence of CS-OIDP attributed to malocclusion, by level of normative orthodontic treatment need (P = 0.042). The prevalence of such impacts increased from 16.8% for adolescents with no/slight need for orthodontic treatment, to 31.7% for those with definite need for orthodontic treatment. Although findings support the idea that malocclusion has physical, psychological and social effects on quality of life of these adolescents, the inconsistencies in findings between the self-reports of impacts of malocclusion and the assessment of normative needs highlight the shortcomings of using only clinical indexes to estimate orthodontic treatment needs.


Assuntos
Atividades Cotidianas , Efeitos Psicossociais da Doença , Má Oclusão/classificação , Avaliação das Necessidades , Qualidade de Vida/psicologia , Adolescente , Distribuição de Qui-Quadrado , Inquéritos de Saúde Bucal , Nível de Saúde , Humanos , Má Oclusão/fisiopatologia , Má Oclusão/psicologia , Ortodontia Corretiva , Perfil de Impacto da Doença
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