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1.
Environ Sci Pollut Res Int ; 30(40): 92950-92962, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37501024

RESUMO

Rice cultivation on paddy soil is commonly associated with emissions of methane, a greenhouse gas, but rice varieties may differ in their actual level of emissions. This study analysed methane emissions associated with 22 distinct rice genotypes, using gas chromatography, and identified the cultivar Heijing 5 from northern China as a potential low-methane rice variety. To confirm this and to examine whether Heijing 5 can perform similarly at higher latitudes, Heijing 5 was cultivated in field trials in China (lat. 32° N) and Sweden (lat. 59° N) where (i) methane emissions were measured, (ii) methanogen abundance in the rhizosphere was determined using quantitative PCR, and (iii) the concentrations of nutrients in water and of heavy metals in rice grain and paddy soil were analysed. The results demonstrated that the low-methane rice cultivar Heijing 5 can successfully complete an entire growth period at high-latitude locations such as central Sweden. Massively parallel sequencing of mRNAs identified candidate genes involved in day length and cold acclimatisation. Cultivation of Heijing 5 in central Sweden was also associated with relatively low heavy metal accumulation in rice grains and lowered nutrient losses to neighbouring water bodies.


Assuntos
Agricultura , Oryza , Agricultura/métodos , Temperatura , Metano/análise , Solo/química , China , Óxido Nitroso/análise
2.
Plants (Basel) ; 12(23)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38068669

RESUMO

Timothy (Phleum pratense) is a cool-season perennial forage grass widely grown for silage and hay production in northern regions. Climate change scenarios predict an increase in extreme weather events with fluctuating periods of high rainfall, requiring new varieties adapted to waterlogging (WL). Wild accessions could serve as germplasm for breeding, and we evaluated the responses of 11 wild and 8 domesticated accessions of timothy, P. nodosum and P. alpinum from different locations in northern Europe. Young plants at tillering stage were exposed to WL for 21 days in a greenhouse, and responses in growth allocation and root anatomy were studied. All accessions produced adventitious roots and changed allocation of growth between shoot and root as a response to WL, but the magnitude of these responses varied among species and among accessions. P. pratense responded less in these traits in response to WL than the other two species. The ability to form aerenchyma in the root cortex in response to WL was found for all species and also varied among species and among accessions, with the highest induction in P. pratense. Interestingly, some accessions were able to maintain and even increase root growth, producing more leaves and tillers, while others showed a reduction in the root system. Shoot dry weight (SDW) was not significantly affected by WL, but some accessions showed different and significant responses in the rate of production of leaves and tillers. Overall correlations between SDW and aerenchyma and between SDW and adventitious root formation were found. This study identified two wild timothy accessions and one wild P. nodosum accession based on shoot and root system growth, aerenchyma formation and having a root anatomy considered to be favorable for WL tolerance. These accessions are interesting genetic resources and candidates for development of climate-resilient timothy varieties.

3.
Plants (Basel) ; 12(19)2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37836234

RESUMO

Timothy grass (Phleum pratense L.) is one of the most important forage crops in temperate regions. Forage production, however, faces many challenges, and new cultivars adapted to a changing climate are needed. Wild populations and relatives of timothy may serve as valuable genetic resources in the breeding of improved cultivars. The aim of our study is to provide knowledge about the phenotypic diversity in domesticated (cultivars, breeding lines and landraces) and wild timothy and two closely related species, P. nodosum (lowland species) and P. alpinum, (high altitude species) to identify potential genetic resources. A total of 244 accessions of timothy and the two related species were studied for growth (plant height, fresh and dry weight) and plant development (days to stem elongation, days to booting and days to heading) in the field and in a greenhouse. We found a large diversity in development and growth between the three Phleum species, as well as between the accessions within each species. Timothy showed the highest growth, but no significant difference was found between wild accessions and cultivars of timothy in fresh and dry weight. However, these two groups of accessions showed significant differences in plant development, where timothy cultivars as a group reached flowering earlier than the wild accessions. This suggests that there has not been a strong directional selection towards increased yield during the domestication and breeding of timothy; rather, timothy has been changed for other traits such as earlier heading. Principal component analysis and cluster analysis based on all traits revealed distinct clusters. Accessions falling within the same cluster showed similarities in the development and growth rather than the type of accession. The large diversity found in this study shows the potential of using timothy accessions as genetic resources in crosses with existing cultivars. Also, accessions of P. nodosum with favorable traits can be candidates for the domestication of a novel forage crop, and the high-altitude relative P. alpinum may be a source of genes for the development of more cold and stresstolerant cultivars.

4.
Front Pharmacol ; 12: 598925, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33716737

RESUMO

Background: There is pressing urgency to identify therapeutic targets and drugs that allow treating COVID-19 patients effectively. Methods: We performed in silico analyses of immune system protein interactome network, single-cell RNA sequencing of human tissues, and artificial neural networks to reveal potential therapeutic targets for drug repurposing against COVID-19. Results: We screened 1,584 high-confidence immune system proteins in ACE2 and TMPRSS2 co-expressing cells, finding 25 potential therapeutic targets significantly overexpressed in nasal goblet secretory cells, lung type II pneumocytes, and ileal absorptive enterocytes of patients with several immunopathologies. Then, we performed fully connected deep neural networks to find the best multitask classification model to predict the activity of 10,672 drugs, obtaining several approved drugs, compounds under investigation, and experimental compounds with the highest area under the receiver operating characteristics. Conclusion: After being effectively analyzed in clinical trials, these drugs can be considered for treatment of severe COVID-19 patients. Scripts can be downloaded at https://github.com/muntisa/immuno-drug-repurposing-COVID-19.

5.
J Public Health Manag Pract ; 16(4): 277-84, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20520365

RESUMO

OBJECTIVE: This study characterized longitudinal changes in cigarette smoking and purchase and cessation patterns among low-income smokers in New York State. DESIGN: Longitudinal tobacco use surveys were conducted in 2002 and 2005. Responses from the 2002 and 2005 surveys were compared among participants who completed both surveys. SETTING: New York State. PARTICIPANTS: Adult low-income smokers (n = 274) were recruited from the Department of Social Services office in Erie County, New York, in 2002 and recontacted in 2005. MAIN OUTCOME MEASURES: These included cigarette smoking, cessation and purchase behaviors, awareness and use of the Quitline, and participation in tobacco industry promotions during the 3-year follow-up period. RESULTS: During the 3-year follow-up period, 37 participants (13.5%) stopped smoking. Among smokers, the average number of daily cigarettes smoked decreased from 16.1 to 13.7 cigarettes (P < .01). There were significant increases in the proportion of smokers who reported that they had ever used a stop smoking medication (26.6% to 51.9%), had ever heard of the Quitline (32.5% to 73.0%), or had ever called the Quitline (4.2% to 11.0%). There was an increase in the use of tobacco industry coupons (41.1% to 59.3%). CONCLUSIONS: Findings suggest that state and local tobacco control policies and programs are being increasingly utilized by this population; however, tobacco company price promotions are also being increasingly used, offsetting the public health benefit of the tobacco control policies and programs in this low-income population.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Pobreza/psicologia , Abandono do Hábito de Fumar/psicologia , Fumar/psicologia , Marketing Social , Indústria do Tabaco , Adolescente , Adulto , Feminino , Seguimentos , Inquéritos Epidemiológicos , Linhas Diretas , Humanos , Masculino , Pessoa de Meia-Idade , New York/epidemiologia , Fumar/epidemiologia , Abandono do Hábito de Fumar/métodos , Poluição por Fumaça de Tabaco/legislação & jurisprudência , Adulto Jovem
6.
Acupunct Electrother Res ; 31(1-2): 33-44, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17063829

RESUMO

The effect of acupuncture stimulation at Zusanli point (ST.36) on the bioavailability of radio-pharmaceutical 99mTc-sodium pertechnetate (Na99mTcO4) in Wistar rats was investigated. Ten healthy rats were allocated into two groups of five. Group 1 (n=5) was treated by acupuncture by inserting stainless steel needles bilaterally at ST.36; Group 2 was the untreated control. Ocular plexus administration of 0.3ml of Na99mTcO4 (3.7MBq) was carried out 10 minutes after every needle insertion. The rats were killed 25 minutes later. The organs were isolated, the radioactivity determined in a well gamma counter, and the percentage of injected radio-pharmaceutical dose per gram of tissue (%ID/g) was assessed for each organ. The %ID/g varied significantly (p<0.05) between Group 1 and Group 2 in pancreas (0.91 +/- 0.17 vs 0.15 +/- 0.03), stomach (7.97 +/- 0.68 vs 3.51 +/- 0.22), spleen (0.97 +/- 0.11 vs 0.41 +/- 0.14), brain (0.19 +/- 0.09 vs 0.09 +/- 0.04), kidneys (0.91 +/- 0.17 vs 0.15 +/- 0.03), heart (0.81 +/- 0.17 vs 0.31 +/- 0.02) and testis (0.46 +/- 0.04 vs 0.14 +/- 0.03). These findings suggest that the effect of acupuncture at ST.36 modulated organs and tissues responses in rats. Using Chinese theories of Zang-Fu and Five Phases, we suggest that the relationship between acupoints and organs may be related to neuromodulation mechanisms such as somatovisceral reflex responses, which play an important role in the autonomic nervous system. These results also suggest that the effect of acupuncture on the bio-availability of radio-pharmaceuticals may help our understanding of the action of acupuncture points on various organs and tissues.


Assuntos
Pontos de Acupuntura , Pertecnetato Tc 99m de Sódio/farmacocinética , Animais , Disponibilidade Biológica , Masculino , Ratos , Ratos Wistar
7.
Appl Radiat Isot ; 70(1): 59-62, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21924619

RESUMO

We evaluated the in vitro effect of an aqueous extract of Ginkgo biloba (EGb) on the distribution in blood cells (BC) and plasma (P) and on the binding of Na(123)I to the blood constituents using precipitation with trichloroacetic acid. The radioactivity percentages insoluble (SF) and insoluble fraction (IF) of blood constituents were determined. The EGb interfered (p<0.05) on the distribution of Na(123)I in the P (from 69.64 to 86.13) and BC (from 30.36 to 13.87) and altered the fixation of the Na(123)I in IF-P and in IF-BC.


Assuntos
Análise Química do Sangue/métodos , Proteínas Sanguíneas/química , Ginkgo biloba/química , Extratos Vegetais/química , Mapeamento de Interação de Proteínas/métodos , Iodeto de Sódio/química , Humanos , Radioisótopos do Iodo/química , Ligação Proteica
8.
Biol Res ; 40(2): 131-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18064350

RESUMO

The radiobiocomplexes labeled with technetium-99m (Tc-99m) have been widely used in nuclear medicine in single photon emission computed tomography and in basic research. The aim of this study was to assess the influence of a Nectandra membranacea extract on the bioavailability of the sodium pertechnetate (Na(99m)TcO(4)) radiobiocomplex in rat organs. The animals were treated with a N. membranacea extract (30 mg/ ml), for 6 days. Na(99m)TcO(4) was injected, the organs were isolated and weighed, and the radioactivity was determined in each organ (%ATI/organ). The %ATI/organ was divided by the mass of each organ to calculate the %ATI/g. A significant increase of the %ATI/organ of Na(99m)TcO(4) was observed in muscle and thyroid as well as in the %ATI/g in the heart, kidney and thyroid. These findings could result from the interaction between components of the plant extract and the radiobiocomplex which may influence the uptake Na(99m)TcO(4) in rat organs. Therefore, precaution is suggested in the interpretation of nuclear medicine results in patients using this herb.


Assuntos
Lauraceae/química , Extratos Vegetais/farmacologia , Compostos Radiofarmacêuticos/farmacocinética , Pertecnetato Tc 99m de Sódio/farmacocinética , Animais , Feminino , Ratos , Ratos Wistar , Distribuição Tecidual/efeitos dos fármacos
9.
Rev. bras. farmacogn ; 22(5): 1060-1069, Sept.-Oct. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-649661

RESUMO

Wistar rats (n=20) were divided in two groups: G1 received 2 mg/kg of GBE (Ginkgo biloba extract 761), whereas G2 received the same volume of a sodium chloride solution (0.9%), both for 10 days. After a 7-day interval, the treatment was repeated for 8 days. Urine volume and food and water intake were measured daily during this protocol. Histological assessments were performed. No significant difference (p>0.05) was observed in food and water intake of animals during treatment with GBE. Animals who received GBE had a smaller urine volume and increase of weight with a significance difference (p<0.05) during the first and second exposure period. No histological alteration was observed in tissues, except for the kidney of the experimental group, which revealed a higher concentration of red cells in the glomerulus with a strong staining for Vascular Endothelial Growth Factor (VEGF). The introduction of GBE (therapeutic dose) in health rats may promote alterations in the physiology of the kidney, but no sufficient to modify the glomerulus architecture, including at ultra structural level (electron microscopy).

10.
Rev. chil. ter. ocup ; (10): 59-72, dic. 2010. tab
Artigo em Espanhol | LILACS | ID: lil-600360

RESUMO

Introducción: Un porcentaje significativo de personas que adquieren una lesión cerebral necesita programas de rehabilitación ambulatoria. En Chile predomina aún un modelo biomédico de rehabilitación, no obstante, las nuevas guías clínicas recomiendan un abordaje interdisciplinario que considere las necesidades del paciente y su familia. Actualmente existe un vacío respecto a cómo operacionalizar intervenciones eficaces que respondan a este paradigma. Objetivo: Encontrar evidencia que permita el desarrollo y evaluación de enfoques en neurorehabilitación ambulatoria de personas con lesión cerebral adquirida y las posibles metodologías de operacionalización de estos. Metodología: Revisión inductiva y conceptual de la literatura. Resultados: En la literatura chilena no existe evidencia empírica ni desarrollos sistemáticos sobre los fundamentos y la efectividad de los programas de rehabilitación ambulatoria para estas personas. En la literatura internacional se destacan tres enfoques: el enfoque holista, el centrado en el cliente y el basado en la planificación de metas. Si bien tales enfoques permiten guiar las acciones de los equipos, la evidencia de su efectividad, en base al criterio de expertos y pequeños estudios longitudinales y de caso único, es aun limitada. Conclusiones: Esencial a la construcción de identidad de un equipo de rehabilitación es determinar los principios y enfoques que sustente su labor. La complejidad y diversidad de los pacientes en la fase ambulatoria requiere que los equipos posean claros fundamentos para guiar la constante toma de decisiones. Es necesaria la evaluación de la eficacia de los programas de rehabilitación ambulatoria en Chile, desarrollando metodologías acordes a la naturaleza multifactorial del fenómeno.


Introduction: A significant percentage of people who acquire a Brain Injury need outpatient rehabilitation programs. In Chile the rehabilitation field is in a transitional stage. Even though the biomedical model is predominant in rehabilitation, the clinical guidelines have begun to recommend an interdisciplinary approach that considers patients needs and their families. Now-a-days, there is a gap on how to operationalize effective interventions responding to this paradigm. Objectives: To find evidence that sustains the development and assessment of outpatient neurorehabilitation approaches of people with brain injury and, to describe the possible operationalization methodologies of these. Methodology: Inductive and conceptual review of literature. Results: In Chilean Literature does not exist empirical evidence nor systematic developments on the foundations and effectiveness of outpatient rehabilitation programs for people with brain injury. International Literature describes three approaches: holistic, client centered, and goal-based. While such approaches can guide the team actions, the evidence of their effectiveness, based on expert criteria and small longitudinal studies and single case studies is still limited. Conclusions: For the development of a rehabilitation team identity, it is essential to determine the principles and approaches that support their work. Due to complexity and diversity of patients in the ambulatory phase, it is crucial that teams have clear foundations to guide the constant decision making. The evaluation of the effectiveness of ambulatory programs in Chile is a necessity; also it is to develop methodologies according to the nature of the phenomenon.


Assuntos
Humanos , Assistência Ambulatorial , Equipe de Assistência ao Paciente , Reabilitação/métodos , Lesões Encefálicas Traumáticas/reabilitação , Modelos Teóricos
11.
DST j. bras. doenças sex. transm ; 22(2): 57-59, 2010. graf, tab
Artigo em Inglês | LILACS | ID: lil-573316

RESUMO

Introduction: the lesions caused by herpes simplex are common and have symptoms affecting the quality of life of affected people. Objective: this study aims to assess the safety efficacy of cream with Uncaria tomentosa (cat?s claw), for topical treatment of the herpes labialis. Methods: a clinical investigation was undertaken by means of controlled, randomized, double-blinded protocol in humans. According to the regulatory procedures, 74 patients were selected based on inclusion/exclusion criteria previously submitted to the Local Ethical Committee (no 144/02) whenever herpes labialis lesion appeared. Following, those selected through medical evaluation received either the test (Uncaria) or the reference (Acyclovir) drug. Results: fifty-four episodes of herpes labialis lesions ecloded in 31 volunteers. After their clinical assessment, one showed 4 episodes, two had 3 episodes and six had 2 infections. Hence, 27 patients received the reference drug while 27 applied the Uncaria cream four times a day. Overall, there were not significant differences between either responses. Although, the Uncaria group showed lower scores on the first two days of treatment (p < 0,005; t = 0,028), on day 3, it was even to Acyclovir. Conclusion:the assessment of clinical efficacy of either treatment demonstrated that both drugs were safe as no adverse reactions were reported. Futher, there was no difference (p > 0,05) in the overall period infections as well as in the inflammatory process or crost formation. Regarding the severity of inflammatory reaction, the clinical efficacy of Uncaria tomentosa was significantly better than acyclovir. Rather than the being antiviral drug, the Uncaria tomentosa may act as an anti-inflammatory agent and this would possibly represent an advantage of not inducing viral resistance for long use.


Introdução: as lesões causadas por herpes simples são comuns e apresentam sintomatologia que altera a qualidade de vida das pessoas acometidas. Objetivo: este estudo visa avaliar a eficácia da segurança de creme com Uncaria tomentosa (unha-de-gato) para o tratamento tópico de herpes labial. Métodos: a pesquisa clínica foi realizada por meio de protocolo controlado, randomizado e duplo-cego. De acordo com os procedimentos de regulamentação, 74pacientes foram selecionados com base em critérios de inclusão e exclusão previamente submetidos à Comissão de Ética Local (no 144/02), sempre a lesão de herpes labial apareceu. Em seguida, os selecionados através de avaliação médica receberam o produto-teste (Uncaria) ou o de referência (aciclovir).Resultados: cinquenta e quatro episódios de lesões de herpes labial eclodiram em 31 voluntários. Após a avaliação clínica, um apresentou quatro episódios, dois tiveram três episódios e seis tinham duas infecções. Assim, 27 pacientes receberam a droga de referência, enquanto 27 aplicaram o creme Uncaria quatro vezes por dia. Em geral, não houve diferença significativa entre as respostas. Contudo, o grupo de Uncaria apresentou escores inferiores nos dois primeiros dias de tratamento (p < 0,005 t = 0,028), depois do dia 3, foi similar ao aciclovir. Conclusão: a avaliação da eficácia clínica dos tratamentosdemonstraram que ambas as drogas foram seguras, bem como não foram notificadas reações adversas. Além disso, não houve diferença significativa (p 0,05) no período total de infecções, bem como no processo inflamatório ou na formação de crosta. Quanto à gravidade da reação inflamatória, a eficácia clínica da Uncaria tomentosa foi significativamente melhor do que o aciclovir. Em vez de a droga ser antiviral, a Uncaria tomentosa pode atuar como um agente anti-inflamatório e isso, possivelmente, representa uma vantagem de não induzir resistência viral para uso por muito tempo.


Assuntos
Humanos , Masculino , Feminino , Adulto , Aciclovir , Unha-de-Gato , Avaliação de Medicamentos , Herpes Labial/terapia , Herpes Simples/terapia , Método Duplo-Cego
12.
Can J Physiol Pharmacol ; 82(12): 1091-5, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15644951

RESUMO

Phytic acid occurs in foods derived from plants. We have investigated the possibility that phytic acid and stannous fluoride are capable of altering the physiological properties (osmotic fragility) and morphological properties of red blood cells (RBC). Osmotic fragility was unchanged by the presence of phytic acid and stannous fluoride in the studied concentrations, but RBC morphology was modified in the presence of the studied substances. In conclusion, the alterations to RBC morphology were not sufficient to promote modifications in osmotic fragility. Our results suggest that the chelating properties of phytic acid could be responsible for the observed effects.


Assuntos
Eritrócitos/efeitos dos fármacos , Eritrócitos/ultraestrutura , Ácido Fítico/farmacologia , Fluoretos de Estanho/farmacologia , Animais , Técnicas In Vitro , Fragilidade Osmótica , Ratos , Ratos Wistar , Cloreto de Sódio/farmacologia
13.
Cell Mol Biol (Noisy-le-grand) ; 48(7): 751-5, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12619970

RESUMO

Sechium edule (chayotte) is used as food or as medication in popular medicine. The labeling of blood elements with technetium-99m (99mTc) has been altered by drugs (synthetic and natural). Some authors have reported biological effects concerning the chayotte. We have evaluated the influence of chayotte extracts (macerated and infusion) on the labeling of blood elements with 99mTc. In vitro study, blood was incubated with the extracts, (6.25, 12.5, 25, 50 and 100% v/v). In in vivo study, the animals were treated with the extracts (100% v/v), as drinking water (15 and 60 days) and samples of blood were withdrawn. The blood samples were incubated with stannous chloride and with 99mTc. Plasma (P) and blood cells (BC) were isolated, also precipitated with trichloroacetic acid and soluble (SF) and insoluble fractions (IF) separated. There was a (p < 0.05) decrease in the radioactivity in BC, IF-BC and IF-P with the infusion (100%) and a slight decrease in the uptake of 99mTc by BC and a strong decrease in the fixation in IF-P with the macerated when the extracts were administrated in vivo (15 days). In 60 days, there was a decrease in BC (98.77 to 53.53%), in IF-BC (90.36 to 21.20%) and in IF-P (77.20 to 11.01%). In vitro study no alterations on the labeling of blood elements were found, however, we have found alterations on the fixation of 99mTc in the in vivo study, probably, due to the metabolization of chayotte capable to induce the generation of active metabolites.


Assuntos
Proteínas Sanguíneas/metabolismo , Cucurbitaceae/química , Eritrócitos/efeitos dos fármacos , Eritrócitos/diagnóstico por imagem , Tecnécio/sangue , Animais , Eritrócitos/metabolismo , Técnicas In Vitro , Extratos Vegetais/farmacologia , Cintilografia , Compostos Radiofarmacêuticos/sangue , Ratos , Ratos Wistar , Solubilidade
14.
Braz. arch. biol. technol ; 52(3): 601-609, May-June 2009. ilus, graf
Artigo em Inglês | LILACS | ID: lil-520912

RESUMO

Food allergy is an adverse reaction that occurs in susceptible people when they eat sensitizing foods and is one of the causes of Inflammatory Bowel Disease (IBD). The effort to understand the induction process of these diseases is important as IBD is increasing worldwide, including in Brazil. The aim of this study was to develop an experimental antigen specific inflammatory process of the gut of mice and rats, using peanut seeds. Animals were immunized with peanut protein extract before their exposure to the in natura peanut seeds. Results showed that systemic immunization with peanut protein extracts rendered significantly higher antibody titers than control groups and that immunized animals submitted to a challenge diet containing peanuts presented time dependent alterations of the gut similar to celiac disease. In conclusion, results suggested that this experimental model was a convenient tool to study the evolution of alterations in chronic antigen specific gut inflammatory process.


A alergia alimentar consiste em uma reação adversa que ocorre em pessoas susceptíveis quando ingerem alimentos sensibilizantes, sendo uma das causas das Doenças Inflamatórias Intestinais (IBD). O objetivo deste estudo foi desenvolver um protocolo experimental de indução de um processo inflamatório intestinal antígeno-específico em camundongos e ratos. Foi escolhida para a indução deste processo a semente de amendoim. Os animais foram imunizados com o extrato protéico previamente à exposição com a semente in natura. Nossos resultados mostram que a imunização sistêmica com extratos protéicos de amendoim ocasiona títulos significativamente maiores de anticorpos quando comparado ao grupo controle e que os animais imunizados submetidos ao desafio com a dieta contendo exclusivamente amendoim apresentam alterações intestinais tempo-dependente similares àquelas observadas na doença celíaca. Os resultados obtidos sugerem que este modelo experimental constitui uma ferramenta conveniente para avaliar as alterações no processo inflamatório intestinal crônico antígeno-específico

15.
Braz. arch. biol. technol ; 51(spe): 151-155, Dec. 2008. tab
Artigo em Inglês | LILACS | ID: lil-508869

RESUMO

The influence (in vivo and in vitro) of an Uncaria tomentosa extract (Cats claw) on the labeling of red blood cells (RBCs) and plasma and cellular proteins with technetium-99m (Tc-99m) was evaluated. For the in vivo treatment, animals were treated with Cats claw. For the in vitro treatment, heparinized blood was incubated with Cats claw before the addition of stannous chloride (SnCl2) and Tc-99m. Samples of plasma (P) and RBCs were separated and also precipitated with trichloroacetic acid. The soluble and insoluble fractions of P and RBCs were isolated. The analysis of the results of the in vivo study, indicates that there is no significant alteration on the uptake of Tc-99m by the blood constituents, but it significantly decrease (p<0.05) the labeling of blood constituents by in vitro methods. These effects could be due to chelation of stannous and /or pertechnetate ions and blockage of the Tc-99m bindings sites.


O objetivo do presente estudo foi avaliar a influência (in vivo e in vitro) de um extrato de Uncaria tomentosa (unha de gato) na marcação de hemácias e proteínas plasmáticas e celulares com tecnécio-99m (Tc-99m). Para o estudo in vivo, animais foram tratados com um extrato de unha de gato. Para o estudo in vitro, sangue heparinizado foi incubado com o extrato de unha de gato antes da adição de cloreto estanoso (SnCl2) e Tc-99m. Amostras de plasma e células foram separadas e também precipitadas com ácido tricloracético. As frações solúveis e insolúveis foram isoladas. A análise dos resultados do estudo in vivo, indica que não houve alteração significante na captação de Tc-99m pelos constituintes sanguíneos, entretanto, no tratamento in vitro, ocorreu redução significante da marcação de constituintes sanguíneos. Esses efeitos poderiam ser justificados por quelação dos íons estanoso e pertecnetato e bloqueio dos sítios de ligação do Tc-99m.

16.
Braz. arch. biol. technol ; 51(spe): 169-174, Dec. 2008. ilus, tab
Artigo em Inglês | LILACS | ID: lil-508872

RESUMO

The aim of this study was to evaluate the effect of the extracts of Nectandra membranacea (N. membranacea), Ginkgo biloba (EGb) and Passiflora (PEF) on the morphology of red blood cells (RBC), on the biodistribution of sodium pertechnetate (99mTcO4Na), on the morphology of duodenum and on the labeling of blood constituents (BC, IF-P, IF-BC) with technetium-99m (Tc-99m). Morphometry studies also were performed. The results show that EGb promotes alteration of the labeling of BC, IF-P and IF-BC (p<0.05). The N. membranacea extract does not promote significant alteration of the radiolabeling, and PEF extract alters the IF-P labeling. N. membranacea, EGb and PEF extracts were able to alter the RBC morphology (P<0.05). N. membranacea extract and EGb modifies the biodistribution of the 99mTcO4Na, and EGb influences the morphometry of duodenum isolated from rats (P<0.05).


O objetivo deste estudo foi avaliar o efeito de um extrato de Nectandra (N. membranacea), de Ginkgo (EGb) e de Passiflora e. flavicarpa (PEF) na marcação de constituintes sanguíneos (BC, IF-P, IF-BC) com Tc-99m, na morfologia de hemácias (RBC), na biodistribuição do 99mTcO4Na na morfologia do duodeno. Amostras de sangue foram incubadas com os extratos. Tc-99m foi adicionado e as frações do plasma (IF-P) e da célula (IF-BC) foram isoladas. Estudos morfométricos foram realizados. Os resultados mostram que EGb promove alteração na marcação de BC, IF-P e IF-BC. N. membranacea não altera a radiomarcação e PEF altera a marcação de IF-P. O extrato de N. membranacea, EGb e PEF alteraram a morfologia de RBC (p<0.05). Os extratos de N. membranacea e EGb modificam a biodistribuição do 99mTcO4Na, e o EGb influencia a morfometria (p<0.05) do duodeno de ratos.

17.
Braz. arch. biol. technol ; 51(spe): 185-190, Dec. 2008. ilus
Artigo em Inglês | LILACS | ID: lil-508875

RESUMO

Ginkgo biloba extract (EGb) has been used to treat memory and concentration deficits, acts as platelet activatingfactor antagonism and prevents against damages caused by free radicals. EGb is a standardized extract that contains 24% flavonoids and 6% terpenoids. The aim of this work was to evaluate the possible influence of an EGb on the ultrastructure of some organs isolated from rats and on the biodistribution of sodium pertechnetate (99mTcO4Na). The animals were treated with EGb and after six days, received 99mTcO4Na. The organs were isolated and fixed for ultrastructural analysis. The results showed that EGb has modified the ultrastructure of kidney, liver and duodenum and altered the biodistribution of 99mTcO4Na (P<0.05). It is speculated that the substances present in the EGb could act directly or generate metabolites capable to promote changes on the biodistribution of 99mTcO4Na and on the morphology of organs at ultrastructural level.


O extrato de Ginkgo Biloba extract (EGb) tem sido usado para tratar dificuldades de concentração,memória, age como antagonista do fator de ativação de plaquetas e previne contra danos causados por radicais livres. EGb é um extrato padronizado com 24% de flavonóides e 6% de lactonas terpênicas. O objetivo deste estudo foi avaliar o efeito de um EGb na ultraestrutura de alguns órgãos isolados de ratos e na biodistribuição do radiofármaco pertecnetato de sódio (99mTcO4Na). Os animais foram tratados com EGb e após 6 dias receberam 99mTcO4Na. Os órgãos foram isolados e a radioatividadedeterminada. Os tecidos foram fixados para microscopia eletrônica. Os resultados mostraram que EGb alterou a ultraestrutura do rim, figado e duodeno e modificou a biodistribuição do99mTcO4Na. Sugerimos que substâncias presentes no EGb poderiam agir diretamente ou gerar metabólitos capazes de promover alterações nabiodistribuição e na morfologia de órgãos em nível ultraestrutural.

18.
Braz. arch. biol. technol ; 50(spe): 153-159, Sept. 2007. ilus, graf
Artigo em Inglês | LILACS | ID: lil-478778

RESUMO

Passiflora edulis f. flavicarpa (maracuja) is a fruit consumed in Brazil and worldwide. Blood constituents labeled with technetium-99m (99mTc) are used in nuclear medicine. The effect of P. flavicarpa extract on the radiolabeling of blood constituents and on red blood cells morphology was evaluated. Blood samples from Wistar rats was incubated with P. flavicarpa extract. After that, the labeling of blood constituents with 99mTc was carried out. Samples of plasma and blood cells were precipitated with trichloroacetic acid to isolate the soluble and insoluble fractions of plasma and blood cells. The radioactivity in each fractions was counted and the percentage of radioactivity was determined. Blood smears were also prepared to morphological evaluation and perimeter/area ratio determination. P. flavicarpa extract altered (p<0.05) the fixation of 99mTc on plasma proteins and the perimeter/area ratio of red blood cells. Substances present in P. flavicarpa extract could affect the labeling of blood constituents with 99mTc acting in specific targets as membrane of red blood cells.


Passiflora edulis f. flavicarpa (maracujá) é um fruto consumido no Brasil e no mundo. O efeito de um extrato de farinha da casca de maracujá na marcação dos constituintes sangüíneos com tecnécio-99m e na morfologia de hemácias foi avaliado. Amostras de sangue de ratos Wistar, foram incubadas com extrato de P. flavicarpa. Em seguida, o procedimento de marcação de constituintes sangüíneos com Tc-99m foi realizado. Amostras de plasma e células sangüíneas foram separadas e alíquotas destas frações foram precipitadas com ácido tricloroacético para isolamento das frações solúvel e insolúvel do plasma e das células sangüíneas. A radiatividade em cada fração foi contada a porcentagem de radioatividade ( por centoATI) foi calculada. Distensões sangüíneas foram também preparadas para avaliação morfológica e da relação perímetro/área de hemácias. O extrato de P. flavicarpa alterou a fixação do 99mTc nas proteínas plasmáticas e a relação perímetro/área das hemácias. Substâncias presentes no extrato de P. flavicarpa poderiam afetar a marcação de constituintes sangüíneos com 99mTc atuando em alvos específicos, como a membrana das hemácias.

19.
Braz. arch. biol. technol ; 50(spe): 167-174, Sept. 2007. ilus, tab
Artigo em Inglês | LILACS | ID: lil-478780

RESUMO

Arctium lappa (burdock) has been used to treat inflammatory processes. Blood constituents labeled with technetium-99m (99mTc) have been utilized in nuclear medicine. It was evaluated the influence of a burdock extract on the labeling of blood constituents with 99mTc and on the morphometry of red blood cells. Blood samples from Wistar rats were incubated with burdock extract and the radiolabeling procedure was carried out. Plasma and blood cells, soluble and insoluble fractions of plasma and blood cells were separated. The radioactivity in each fraction was counted and the percentages of radioactivity ( percentATI) were determined. Morphology and morphometric (perimeter/area ratio) measurements of red blood cells (RBC) were performed. The incubation with burdock extract significantly (p<0.05) altered the percentATI on the blood compartments and the perimeter/area ratio of RBC, as well as, induced modifications on the shape of RBC. Alterations on membrane could justify the decrease of labeling of blood cells with 99mTc obtained in this study.


Arctium lappa (bardana) tem sido utilizada na medicina popular para o tratamento de processos inflamatórios. Constituintes sangüíneos marcados com tecnécio-99m (99mTc) são utilizados na medicina nuclear para obtenção de imagens. Neste trabalho foi avaliada a influência de um extrato de bardana na marcação de constituintes sangüíneos com 99mTc e na morfologia de hemácias. Amostras de sangue de ratos Wistar foram incubadas com extrato de bardana e o processo de radiomarcação de constituintes sangüíneos foi realizado. Plasma e células sangüíneas, frações solúvel e insolúvel do plasma e das células sangüíneas foram separadas, a radioatividade em cada fração foi contada e as porcentagens de radioatividade ( por centoATI) foram determinadas. A morfologia e a relação perímetro/área das hemácias foram avaliadas. A incubação de sangue com o extrato de bardana alterou significativamente (p<0.05) a por centoATI a distribuição de radioatividade nos compartimentos plasmático e celular. A relação perímetro/área de hemácias, bem como a forma das hemácias também sofreram alterações Modificações na membrana poderiam justificar a diminuição da marcação das células sangüíneas com 99mTc obtidas neste estudo.

20.
Biol. Res ; 40(2): 131-135, 2007. tab
Artigo em Inglês | LILACS | ID: lil-468184

RESUMO

The radiobiocomplexes labeled with technetium-99m (Tc-99m) have been widely used in nuclear medicine in single photon emission computed tomography and in basic research. The aim of this study was to assess the influence of a Nectandra membran cea extract on the bioavailability of the sodium pertechnetate (Na99mTc0(4)) radiobiocomplex in rat organs. The animals were treated with a N. membran cea extract (30 mg/ ml), for 6 days. Na99mTc0(4) was injected, the organs were isolated and weighed, and the radioactivity was determined in each organ ( percentATI/organ). The percentATI/organ was divided by the mass of each organ to calculate the percentATI/g. A significant increase of the percentATI/organ of Na99mTc0(4) was observed in muscle and thyroid as well as in the percentATI/g in the heart, kidney and thyroid. These findings could result from the interaction between components of the plant extract and the radiobiocomplex which may influence the uptake Na99mTc0(4) in rat organs. Therefore, precaution is suggested in the interpretation of nuclear medicine results in patients using this herb.


Assuntos
Animais , Feminino , Ratos , Lauraceae/química , Extratos Vegetais/farmacologia , Compostos Radiofarmacêuticos/farmacocinética , /farmacocinética , Ratos Wistar , Distribuição Tecidual/efeitos dos fármacos
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