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1.
Cureus ; 16(5): e59819, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38846242

RESUMO

Background Drug and substance abuse remains a major medical problem worldwide. Amphetamines are potent stimulants of the central nervous system. Amphetamine abuse is highly prevalent among drug-dependents. This study was conducted in Qassim, Saudi Arabia, to evaluate amphetamine's toxic effects on major and trace elements and their correlation with redox status. Methods The study involved amphetamine-only patients admitted to the Erada Rehabilitation Centre from March to October 2023. Urine samples were analysed from both normal subjects and amphetamine-dependent groups. Results Urinary sodium and chloride levels were significantly higher in the amphetamine-dependent group than in the control group, while their calcium levels decreased. Lipid peroxidase levels significantly increased in people with a substance use disorder (SUD), indicating oxidative stress. Together, their total antioxidant capacity decreased. Zinc (Zn), copper (Cu), lead (Pb), cadmium (Cd), sodium (Na), and total antioxidant capacity levels were positively correlated with lipid peroxidase. Conclusions Amphetamine-dependent people are more likely to experience a variety of health problems. This study found a direct correlation between an imbalance in major and trace elements and the redox status.

2.
Plants (Basel) ; 13(3)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38337891

RESUMO

Terrestrial algae are a group of photosynthetic organisms that can survive in extreme conditions. pH is one of the most important factors influencing the distribution of algae in both aquatic and terrestrial ecosystems. The impact of different pH levels on the cell volume and other morphological characteristics of authentic and reference strains of Chlorella vulgaris, Bracteacoccus minor, Pseudoccomyxa simplex, Chlorococcum infusionum, and Vischeria magna were studied. Chlorella vulgaris, Pseudoccomyxa simplex, and Vischeria magna were the most resistant species, retaining their morphology in the range of pH 4-11.5 and pH 3.5-11, respectively. The change in pH towards acidic and alkaline levels caused an increase in the volume of Pseudoccomixa simplex and Vischeria magna cells, according to a polynomial regression model. The volume of Chlorella vulgaris cells increased from a low to high pH according to a linear regression model. Changes in pH levels did not have a significant impact on the volume of Bracteacoccus minor and Chlorococcum infusionum cells. Low and high levels of pH caused an increase in oil-containing substances in Vischeria magna and Bracteacoccus minor cells. Our study revealed a high resistance of the studied species to extreme pH levels, which allows for us to recommend these strains for broader use in biotechnology and conservation studies of natural populations.

3.
BioTech (Basel) ; 12(2)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37218759

RESUMO

Hydroponics is a promising method for growing agricultural plants and is especially relevant in the context of global climate change. Microscopic algae, including Chlorella vulgaris, has great potential for use in hydroponic systems as natural growth stimulators. The effect of the suspension of an authentic strain of Chlorella vulgaris Beijerinck on the length of cucumber shoots and roots, as well as its dry biomass, was studied. During cultivation in a Knop medium with the addition of Chlorella suspension, the length of the shoots was shortened from 11.30 to 8.15 cm, while the length of the roots also decreased from 16.41 to 10.59 cm. At the same time, the biomass of the roots increased from 0.04 to 0.05 g. The data obtained indicate the positive effect of the suspension of the Chlorella vulgaris authentic strain on the dry biomass of cucumber plants in hydroponic conditions and make it possible to recommend this strain for use when growing plants in hydroponic systems.

4.
Mar Environ Res ; 184: 105858, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36630747

RESUMO

Macroalgal bloom events have been frequent in recent years. Eutrophication and overexploitation fishing may favor blooms through nutrient availability and capturing top predators. We aim to investigate the drivers of the macroalgae blooms and their consequences on the food web of the two tropical coastal ecosystems: Porto do Mangue (with high macroalgae production) and Baía Formosa (control environment, without macroalgae), both exploited by artisanal fisheries in northeastern Brazil. The food webs are modeled using the Ecopath with Ecosim (EwE) approach. Our results suggest that fishing did not favor macroalgae blooms but rather the high concentration of nutrients added to the semi-arid conditions. Furthermore, the macroalgae bloom showed low trophic impact, so much of their biomass is transferred into detritus. However, when it decomposes, this accumulation of matter alters the structure and functioning of the ecosystem, affecting its main fish resources: shrimp and piscivorous fish. Investigating blooms is key to management.


Assuntos
Ecossistema , Alga Marinha , Animais , Cadeia Alimentar , Pesqueiros , Biomassa , Eutrofização
5.
Food Chem Toxicol ; 146: 111846, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33166674

RESUMO

A biopreservative derived from the fermentation of a dairy byproduct by Enterococcus faecalis UGRA10 strains being developed. This product possesses a strong and wide antibacterial spectrum mainly due to the presence of Enterocin AS-48 in its composition. To assess its potential as food additive, the mutagenicicity and genotoxicity has been assayed by means of the bacterial reverse-mutation assay in Salmonella typhimurium TA97A, TA98, TA100, TA102, TA1535 strains (Ames test, OECD 471, 2020) and the micronucleus test (MN) (OECD 487, 2016) in L5178Y/Tk ± cells. The results in the Ames test after exposure to the byproduct (6.75-100 µg/plate) with absence and presence of the metabolic activation system from rat liver (S9 fraction), revealed not mutagenicity at the conditions tested. For the MN test, the exposition to five enterocin AS-48 concentrations (0.2-1 µg/µl) was tested in the absence and presence of S9 fraction, with no evidence of genotoxicity. Negative results in the mutagenicity and genotoxicity assays point out the good safety profile of the byproduct and support its use as additive. Further toxicological studies are required before its approval and commercial application.


Assuntos
Bacteriocinas/química , Conservantes de Alimentos/química , Conservantes de Alimentos/toxicidade , Animais , Fígado , Testes de Mutagenicidade , Ratos , Salmonella typhimurium
6.
J Appl Microbiol ; 128(5): 1448-1459, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31883415

RESUMO

AIMS: Quality evaluation of fresh whitemouth croaker (Micropogonias furnieri) by histamine determination using the HPLC-DAD method and quantification of histamine-forming bacteria using NGS and qPCR. METHODS AND RESULTS: The histamine content of fresh whitemouth croaker was detected by high performance liquid chromatography with diode array detector with a concentration ranging from 258·52 to 604·62 mg kg-1 being observed. The number of histidine decarboxylase (hdc gene) copies from Gram-negative bacteria and the bacteria Morganella morganii and Enterobacter aerogenes were quantified by quantitative polymerase chain reaction. All samples were positive, with copy numbers of the hdc gene ranging from 4·67 to 12·01 log10 per g. The microbial community was determined by sequencing the V4 region of the 16S rRNA gene using the Ion Torrent platform. The bioinformatics data generated by frog software showed that the phylum Proteobacteria was the most abundant, with the family Moraxellaceae being more prevalent in samples collected in the summer, whereas the Pseudomonadaceae was more present in the winter. CONCLUSIONS: All fish muscle samples analysed in this study presented histamine values higher than those allowed by CODEX Alimentarius. Additionally, a wide variety of spoilage micro-organisms capable of expressing the enzyme histidine decarboxylase were detected. Thus, improvements in handling and processing are required to minimize the prevalence of histamine-producing bacteria in fish. SIGNIFICANCE AND IMPACT OF THE STUDY: Global fish production in 2016 was 171 million tons, with the largest consumer being China, followed by Indonesia and the USA. In Brazil, 1·3 million tons of fish are consumed per year, with whitemouth croaker being the main fish landed. Notably, cases associated with histamine poisoning are quite common. According to the European Food Safety Authority and European Centre for Disease Prevention and Control, a total of 599 HFP outbreaks were identified in the European Union during the period 2010-2017. In the USA, there were 333 outbreaks with 1383 people involved between 1998 and 2008.


Assuntos
Qualidade dos Alimentos , Histamina/análise , Perciformes/microbiologia , RNA Ribossômico 16S/genética , Alimentos Marinhos/microbiologia , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Brasil , Histamina/biossíntese , Histidina Descarboxilase/genética , Histidina Descarboxilase/metabolismo , Microbiota/genética
7.
FEMS Microbiol Lett ; 366(17)2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31633749

RESUMO

A freshwater dwelling, tapering, heterocytous cyanobacterium (strain V13) was isolated from an oligotrophic pond in the Shrirampur taluka, Ahmednagar district of Maharashtra in India. Initial morphological examination indicated that strain V13 belonged to the genus Calothrix. Subsequent molecular and phylogenetic assessment based on 16S rRNA gene, led us to describe the freshwater/terrestrial clade of Calothrix strains without terminal hairs as a new genus Dulcicalothrix gen. nov., with the type species Dulcicalothrix necridiiformans sp. nov. (Strain V13) on the basis of the necridia forming ability of the strain. Also, the 16S-23S ITS secondary structure analysis clearly differentiated strain V13 from the other members of the clade. Past studies and the current state of knowledge makes it imperative to separate the groups Calothrix (marine/freshwater Calothrix), Macrochaete and Dulcicalothrix (freshwater/terrestrial Calothrix) into separate genera in accordance with the International Code of Nomenclature for Algae, Fungi and Plants. Robust phylogenetic evidence and previous reports strongly support the re-erection of the family Calotrichaceae distinct from the existing family Rivulariaceae.


Assuntos
Cianobactérias/classificação , Cianobactérias/genética , Filogenia , DNA Espaçador Ribossômico , Ecossistema , Conformação de Ácido Nucleico , Fenótipo , RNA Ribossômico 16S/genética
8.
Carbohydr Polym ; 190: 339-345, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29628256

RESUMO

Mucoadhesive membranes were proposed in this study as drug delivery system for betamethasone-17-valerate (BMV) in the treatment of recurrent aphthous stomatitis (RAS). The membranes were obtained by using the polymers chitosan (CHI) in both presence and absence of polyvinilpyrrolidone (PVP), following the solvent evaporation method. The presence of PVP in the membranes causes significant modifications in its thermal properties. Changes in the thermal events at 114 and 193 °C (related to BMV melting point), and losses in mass (39.38 and 30.68% for CH:PVP and CH:PVP-B, respectively), suggests the incorporation of BMV in these membranes. However, the morphological aspects of the membranes do not change after adding PVP and BMV. PVP causes changes in swelling ratios (>80%) of the membranes, and it is suggested that the reorganization of the polymer mesh was highlighted by the chemical interactions between the polymers leading to different percentages of BMV released ∼40% and ∼80% from CH-B and CH:PVP-B. BMV release profile follows Korsmeyer and Peppas model (n > 0.89) which suggests that the diffusion of the drug in the swollen matrix is driven by polymer relaxation. In addition, the membranes containing PVP (higher swelling ability) present high rates of tensile strength, and therefore, higher mucoadhesion. Moreover, given the results presented, the developed mucoadhesive membranes are a promising system to deliver BMV for the treatment of RAS.

9.
Exp Oncol ; 39(4): 276-280, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29284778

RESUMO

AIM: In stress research, reducing times of stress induction may contribute to improving the well-being of experimental animals, especially in cancer models, already under physiological distress. To support this idea, we evaluated the effects of a short-timed stress protocol on endocrine, metabolic and immune indicators in mice bearing the L5178Y-R lymphoma. MATERIALS AND METHODS: A 30-minute daily stress protocol was applied for 28 days to healthy and lymphoma-bearing BALB/c mice; body weight, plasma levels of corticosterone, norepinephrine, Th1/Th2 cytokines, insulin, and leptin, were measured. RESULTS: We found a 12% significant decrease in body weight in non-tumor bearing mice under stress (p < 0.007). The disruption of weight evolution was accompanied by a stress induced 85% decrease in plasmatic leptin (p < 0.01) and total reduction of insulin. Tumor burden alone was associated to an increase in more than two-fold of plasmatic levels of norepinephrine (p < 0.008). Neither stress nor tumor or their combination, resulted in an elevation of systemic IL-6. IFN-γ levels were 20 times higher in lymphoma-bearing animals when compared with non-tumor bearing mice (p < 0.01); however, under stress, this response was reduced by half, indicating a suppressing effect of chronic stress on the antitumor immune response. CONCLUSION: A short-timed stress induction is enough to cause significant alterations in the metabolism and immunity of healthy and tumor-bearing mice, supporting the use of short-timed protocols as an efficient way to induce chronic stress that also considers concerns regarding the well-being of experimental animals in biomedical research.


Assuntos
Linfoma/imunologia , Linfoma/metabolismo , Estresse Fisiológico/fisiologia , Animais , Feminino , Camundongos , Camundongos Endogâmicos BALB C
10.
Int J Syst Evol Microbiol ; 67(5): 1296-1305, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28109209

RESUMO

A filamentous, soil-dwelling cyanobacterial strain (9C-PST) was isolated from Mandsaur, Madhya Pradesh, India, and is described as a new species of the genus Nostoc. Extensive morphological and molecular characterization along with a thorough assessment of ecology was performed. The style of filament orientation, type and nature of the sheath (e.g. distribution and visibility across the trichome), and vegetative and heterocyte cell dimensions and shape were assessed for over one year using both the laboratory grown culture and the naturally occurring samples. Sequencing of the 16S rRNA gene showed 94 % similarity with Nostocpiscinale CENA21 while analyses of the secondary structures of the 16S-23S ITS region showed unique folding patterns that differentiated this strain from other species of Nostoc. The level of rbcl and rpoC1 gene sequence similarity was 91 and 94 % to Nostocsp. PCC 7524 and Nostocpiscinale CENA21, respectively, while the nifD gene sequence similarity was found to be 99 % with Nostocpiscinale CENA21. The phenotypic, ecological, genetic and phylogenetic observations indicate that the strain 9C-PST represents a novel species of the genus Nostoc with the name proposed being Nostoc thermotolerans sp. nov. according to the International Code of Nomenclature for Algae, Fungi, and Plants.


Assuntos
Nostoc/classificação , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Genes Bacterianos , Índia , Nostoc/genética , Nostoc/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
11.
Arq. bras. med. vet. zootec ; 68(5): 1343-1350, set.-out. 2016. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-827905

RESUMO

O tiametoxam é um inseticida neonicotinóide usado em diversas culturas e classificado como perigoso para o meio ambiente.O objetivo do presente trabalho foi avaliar a toxicidade aguda do inseticida, por meio da determinação da CL50%, e o risco ecotoxicológico com mensuração da concentração ambiental estimada (CAE) e do quociente de risco (QR). O experimento foi realizado com alevinos de tilápias expostas a 150, 300, 450, 600 e 750mg/L de Actara(R) WG por um período total de 96 horas. O oxigênio dissolvido, o pH e a temperatura foram mensurados diariamente em todos os aquários. Nos grupos experimentais, houve uma variação dos valores de pH e de OD para as diferentes concentrações do inseticida. A CL50% 96h do Actara(R) para alevinos de tilápia foi de 322,08ppm. O quociente de risco (QR) variou de baixo a alto, de acordo com a metodologia usada.(AU)


The neonicotinoid insecticide thiamethoxam is used in different cultures and classified as dangerous for the environment. The aim of this study was to evaluate the acute toxicity of thiamethoxam by determining the lethal concentration (LC50) and ecotoxicological risk through Estimated Environmental Concentration (EEC) and Risk Quotient (RQ) measurement. The assays were done with Tilapia fingerlings exposed to 150, 300, 450, 600 and 750mg / L Actara WG during 96 hours. Dissolved oxygen, pH and temperature were measured daily in all aquariums. Dissolved oxygen and pH varied in the experimental groups. The LC50 Actara(R); 96h was 322.08ppm. The risk quotient (RQ) ranged from low to high according to the methodology used.(AU)


Assuntos
Animais , Testes de Toxicidade Aguda , Ciclídeos , Poluição Ambiental/análise , Inseticidas/toxicidade , Dose Letal Mediana
12.
Enferm. univ ; 13(3): 159-165, jul.-sep. 2016. tab
Artigo em Espanhol | LILACS-Express | LILACS, BDENF - Enfermagem | ID: biblio-840348

RESUMO

Introducción: El envejecimiento es un proceso natural. La calidad e independencia con que se vive esta etapa depende no solo de la estructura genética de los seres humanos, sino también de lo que se realiza durante el curso de vida. Objetivo: Establecer la relación entre calidad de vida del adulto mayor y su nivel de dependencia y autocuidado. Métodos: Estudio transversal, descriptivo y correlacional. Fueron entrevistados 116 adultos mayores que acudieron a consulta en una unidad de salud. Las variables estudiadas fueron: dependencia, autocuidado y calidad de vida. Se utilizaron la Escala de Barthel, la Escala de capacidades de autocuidado y el Cuestionario SF-36 de calidad de vida. Se realizó un análisis descriptivo de las variables y correlación de Pearson y Spearman. El presente proyecto fue revisado y aprobado por un Comité de Investigación. Resultados: El 54.3% de los participantes fueron mujeres. El 80.2% de los adultos mayores encuestados presentaron independencia para realizar las actividades de la vida diaria y el 19.8% presentaron dependencia leve. En la calificación global de las actividades de autocuidado el 22.4% tuvieron buena capacidad y el 76.6%, muy buena capacidad. En la percepción de calidad de vida en la dimensión física, el 24% de los entrevistados consideran que su salud es buena y el 56%, regular. En las pruebas de correlación se encontró mínima relación entre las variables de autocuidado y dependencia; escasa entre autocuidado y grado de escolaridad; correlación positiva entre la dependencia y la calidad de vida, así como la calidad de vida y la edad, aunque el valor de todas las correlaciones fue bajo.


Introduction: Getting old is a natural process. The quality of life and independency lived during this stage depend not only on the genetic structure, but also on what is done throughout the entire life. Objective: To explore the relationship among the levels of quality of life, dependency, and self-care in the elder adult. Methods: This is a transversal, descriptive, and correlational study. One hundred and sixteen elder adults who attended consultation visits at a health unit were interviewed. The variables studied were: dependency, self-care, and quality of life. The Barthel scale, the Self-Care Capacities Scale, and the SF-36 Quality of Life Questionnaire were used. The Pearson and Spearman correlations were calculated. This project was reviewed and approved by a Research Committee. Results: Fifty four point three percent of the participants were female. The 80.2% of the elder adults interviewed showed independence to perform their daily life activities, while the rest (19.8%) showed a mild level of dependency. In relation to the self-care activities, 22.4% showed a good capacity, while 76.6% showed a very good capacity. In relation to their perception of quality of life, in the physical dimension, 24% of the participants considered their health as good, while 56% consider it as more or less good. In the correlation tests, a minimal relationship was found between the variables of self-care and dependency, also, a low relationship was found between the self-care and the school levels. A positive correlation was found between dependency and quality of life, and also between quality of life and age, though their values were low.


Introdução: O envelhecimento é um processo natural. A qualidade e independência com que se vive esta etapa depende não só da estrutura genética dos seres humanos, senão também do que se realiza durante o curso de vida. Objetivo: Estabelecer a relação entre a qualidade de vida do idoso e o seu nível de dependência e autocuidado. Métodos: Estudo transversal, descritivo e de correlação. Foram entrevistados 116 idosos que acudiram a consulta em uma unidade de saúde. As variáveis estudadas foram: dependência, autocuidado e qualidade de vida. Utilizou-se a escala de Barthel, Escala de capacidades de autocuidado e Questionário SF-36 de qualidade de vida. Realizou-se uma análise descritiva das variáveis e correlação de Pearson e Spearman. O presente projeto foi revisado e aprovado por um Comité de Pesquisa. Resultados: 54.3% dos participantes era mulher. O 80.2% dos idosos respondentes apresentou independência para realizar as atividades da vida diária e o 19.8% apresentou dependência leve. Na qualificação global das atividades de autocuidado, 22.4% teve boa capacidade e 76.6% muito boa capacidade. Na percepção de qualidade de vida na dimensão física, 24% dos entrevistados considera que sua saúde é boa e o 56% regular. Nas provas de correlação encontrou-se mínima relação entre as variáveis de autocuidado e dependência, escassa entre autocuidado e grau de escolaridade, correlação positiva entre a dependência e a qualidade de vida, bem como a qualidade de vida e a idade, ainda assim, o valor de todas as correlações foi baixo.


Assuntos
Humanos , Masculino , Feminino , Idoso , Qualidade de Vida , Autocuidado , Idoso , Envelhecimento
13.
J Appl Microbiol ; 121(3): 831-9, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27206682

RESUMO

AIMS: The main goal was to estimate the prevalence of methicillin-resistant Staphylococcus aureus on hands and in nose of health care professionals. METHODS AND RESULTS: Detection of Staph. aureus on hands or in the nose of 169 individuals was performed. Nasal and hand carriage was found in 39·6 and in 8·9% respectively. About 17·2% of the individuals were carriers of methicillin-resistant Staph. aureus (MRSA) in the nose and 4·7% on hands. The majority of nasal MRSA were resistant to ß-lactams, erythromycin and ciprofloxacin. All nasal MRSA were SCCmec type IV and Panton-Valentine leukocidin (PVL) negative. One MRSA isolated from hand was SCCmec type V. About 75·6% of MRSA isolates presented the same or closely related restriction patterns. Sixty per cent of Staph. aureus from hands and from noses from the same individual were the same strain. CONCLUSIONS: MRSA nasal carriage was high considering healthy health care professionals but in accordance with high level of MRSA infection in Portugal. Isolates recovered in this study seemed to be different from major clones previously isolated in other Portuguese hospitals. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings may have implications on the knowledge of healthy health care workers as vehicles of MRSA infections among the community. Presence of several virulence factors may contribute to increased pathogenesis in case of infection.


Assuntos
Mãos/microbiologia , Nariz/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/isolamento & purificação , Adulto , Feminino , Pessoal de Saúde/estatística & dados numéricos , Hospitais , Humanos , Masculino , Resistência a Meticilina , Portugal/epidemiologia , Prevalência , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Adulto Jovem
15.
J Econ Entomol ; 108(5): 2278-88, 2015 10.
Artigo em Inglês | MEDLINE | ID: mdl-26453716

RESUMO

The use of synthetic acaricides for management of pest mites may alter the efficacy of the ectoparasitoid Tamarixia radiata (Waterston) in biological control of Diaphorina citri Kuwayama, the vector of the bacteria associated with huanglongbing (HLB) in citrus orchards. We evaluated the toxicity of 16 acaricides that are recommended for the control of citrus-pest mites to T. radiata. Acrinathrin, bifenthrin, carbosulfan, and fenpropathrin caused high acute toxicity and were considered harmful (mortality >77%) to T. radiata. Abamectin, diflubenzuron, etoxazole, fenbutatin oxide, fenpyroximate, flufenoxuron, hexythiazox, propargite, spirodiclofen, and sulfur caused low acute toxicity and affected the parasitism rate and emergence rate of adults (F1 generation), and were considered slightly harmful to T. radiata. Dicofol and pyridaben did not affect the survival and action of the ectoparasitoid, and were considered harmless. In addition to its acute toxicity, carbosulfan caused mortality higher than 25% for >30 d after application, and was considered persistent. Acrinathrin, bifenthrin, fenpropathrin, fenpyroximate, propargite, and sulfur caused mortalities over 25% until 24 d after application and were considered moderately persistent; abamectin was slightly persistent, and fenbutatin oxide was short lived. Our results suggest that most acaricides used to control pest mites in citrus affect the density and efficacy of T. radiata in the biological control of D. citri. However, further evaluations are needed in order to determine the effect of these products on this ectoparasitoid under field conditions.


Assuntos
Acaricidas/toxicidade , Hemípteros/efeitos dos fármacos , Interações Hospedeiro-Parasita/efeitos dos fármacos , Vespas/efeitos dos fármacos , Animais , Feminino , Hemípteros/crescimento & desenvolvimento , Hemípteros/parasitologia , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Masculino , Ninfa/efeitos dos fármacos , Ninfa/crescimento & desenvolvimento , Controle Biológico de Vetores , Pupa/efeitos dos fármacos , Pupa/crescimento & desenvolvimento , Vespas/crescimento & desenvolvimento , Vespas/fisiologia
16.
J Colloid Interface Sci ; 456: 190-6, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26125515

RESUMO

HYPOTHESIS: Liquid crystalline precursors, which are in situ gelling nanostructured surfactant systems, can undergo phase transition in aqueous solution and become more structured aggregates, controlling release of larvicides and acting as biotechnology alternatives for dengue control. Such systems can contain bioactive substances as Citrus sinensis essential oil (CSEO) which exhibits biological activity against Aedes aegypti (Ae. aegypti) larvae. EXPERIMENTS: The formulations were composed by fixed concentration of CSEO stabilized by Polyoxypropylene (5) Polyoxyethylene (20) Cetyl Ether (PPG-5 CETETH-20): oleic acid (OA) 2:1, increasing water content. The phase diagram was established and systems structure was evaluated by polarized light microscopy (PLM), small angle X-ray scattering (SAXS) and rheology. Median lethal concentration was determined against Ae. aegypti larvae. FINDINGS: The phase diagram exhibited four regions: liquid crystal (LC), emulsion, microemulsion (ME) and phase separation. The PLM and SAXS distinguished microemulsions, lamellar and hexagonal LC structures. Flow and oscillatory tests showed that increasing water content increases elasticity from Newtonian to non-newtonian behavior confirming the in situ gelation behavior. The larvicidal activity of formulations indicates that these nanostructured systems improved the oil solubility in aqueous medium and in addition are potential environmental larvicide against Ae. aegypti larvae.


Assuntos
Aedes/efeitos dos fármacos , Dengue/prevenção & controle , Inseticidas/química , Óleos Voláteis/química , Tensoativos/química , Animais , Citrus , Sistemas de Liberação de Medicamentos , Emulsões , Géis , Humanos , Cristais Líquidos/química , Nanoestruturas/química , Espalhamento de Radiação , Espalhamento a Baixo Ângulo , Viscosidade , Água/química , Difração de Raios X , Raios X
17.
J Phycol ; 51(6): 1040-54, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26987000

RESUMO

Members of the morphologically unusual cyanobacterial family Gomontiellaceae were studied using a polyphasic approach. Cultured strains of Hormoscilla pringsheimii, Starria zimbabweënsis, Crinalium magnum, and Crinalium epipsammum were thoroughly examined, and the type specimen of the family, Gomontiella subtubulosa, was investigated. The results of morphological observations using both light microscopy and transmission electron microscopy were consistent with previous reports and provided evidence for the unique morphological and ultrastructural traits of this family. Analysis of the 16S rRNA gene confirmed the monophyletic origin of non-marine repre-sentatives of genera traditionally classified into this family. The family was phylogenetically placed among other groups of filamentous cyanobacterial taxa. The presence of cellulose in the cell wall was analyzed and confirmed in all cultured Gomontiellaceae members using Fourier transform infrared spectroscopy and fluorescence microscopy. Evaluation of toxins produced by the studied strains revealed the hepatotoxin cylindrospermopsin (CYN) in available strains of the genus Hormoscilla. Production of this compound in both Hormoscilla strains was detected using high-performance liquid chromatography in tandem with high resolution mass spectrometry and confirmed by positive PCR amplification of the cyrJ gene from the CYN biosynthetic cluster. To our knowledge, this is the first report of CYN production by soil cyanobacteria, establishing a previously unreported CYN-producing lineage. This study indicates that cyanobacteria of the family Gomontiellaceae form a separate but coherent cluster defined by numerous intriguing morphological, ultrastructural, and biochemical features, and exhibiting a toxic potential worthy of further investigation.

19.
J Ethnopharmacol ; 127(2): 451-6, 2010 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-19837149

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Bowdichia virgilioides Kunth (Leguminosae Papilonoideae) is a plant with anti-inflammatory activity used in folk medicine. The importance of this plant promoted its inclusion in Brazilian Pharmacopoeia. AIM OF THE STUDY: In order to evaluate the actions of this plant, studies were performed on antinociceptive and anti-inflammatory activities. MATERIALS AND METHODS: The aqueous extracts (AE) of Bowdichia virgilioides inner bark and leaves were used at 100, 200, and 400mg/kg. Antinociceptive activity of plant extract was evaluated by writhing, hot-plate and formalin tests. Anti-inflammatory activity was evaluated using paw oedema and peritonitis methods. RESULTS: Oral treatment with the AE of inner bark or leaves elicited inhibitory activity (P<0.01) on acetic acid effect at 200 and 400mg/kg, and reduced the formalin effect at the second-phase (200 and 400mg/kg, P<0.01), however it did not elicit any inhibitory effect on hot-plate test. The indomethacin inhibited the acetic acid-induced writhing and the formalin effect at the second-phase (P<0.001), and the morphine reduced the both phases of formalin test (P<0.001). Carrageenan-induced oedema formation and neutrophil migration into the peritoneal cavity were reduced with the AE of inner bark or leaves at 100, 200, and 400mg/kg (P<0.05), and by the reference compounds aspirin (P<0.001) and dexamethasone (P<0.001), respectively. CONCLUSIONS: The AE of Bowdichia virgilioides shows antinociceptive and anti-inflammatory activities, supporting the folkloric usage of the plant to treat various inflammatory diseases.


Assuntos
Analgésicos/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Fabaceae , Extratos Vegetais/uso terapêutico , Analgésicos/isolamento & purificação , Analgésicos/farmacologia , Animais , Anti-Inflamatórios não Esteroides/isolamento & purificação , Anti-Inflamatórios não Esteroides/farmacologia , Relação Dose-Resposta a Droga , Edema/tratamento farmacológico , Edema/patologia , Feminino , Masculino , Camundongos , Medição da Dor/efeitos dos fármacos , Medição da Dor/métodos , Casca de Planta , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Folhas de Planta , Ratos , Ratos Wistar
20.
Arq. bras. med. vet. zootec ; 61(3): 621-627, jun. 2009. ilus, tab
Artigo em Português | LILACS | ID: lil-519455

RESUMO

Avaliou-se o uso de brânquias, fígado e rins como biomarcadores histológicos em ensaio de toxicidade crônica com o herbicida Roundup® em piauçu (Leporinus. macrocephalus). Para tanto, os animais foram expostos a 1,58mg/L, dose equivalente a 1/10 da CL50 para a espécie por 14 e 28 dias, sendo utilizados cinco animais por tratamento correspondentes aos dias 0, 14 e 28. Hemorragia e necrose hepática e congestão renal foram as alterações que apresentaram diferenças entre os animais expostos e os não expostos. Dentre os órgãos usados como biomarcadores histopatológicos, o fígado foi o que apresentou os melhores resultados, seguido pelo rim.


The use of gills, liver, and kidneys as histological biomarkers was evaluated in a chronic toxicity analysis with herbicide Roundup® in piauçu (Leporinus macrocephalus). The animals were exposed to 1/10 of LC50 (1.58mg/L), during a period of 14 and 28 days. Five animals were used for treatment (days 0, 14, and 28). Hepatic hemorrhage and necrosis and renal congestion were the alterations that presented differences between exposed and non-exposed animals. Among the organs used as histological biomarkers, the liver presented the best results, followed by the kidneys.


Assuntos
Animais , Brânquias , Herbicidas/farmacologia , Rim , Fígado , Biomarcadores , Peixes/anatomia & histologia , Testes de Toxicidade Crônica/análise
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