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1.
Braz J Biol ; 84: e276874, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38808783

RESUMO

Strawberry (Fragaria x ananassa Duch.) is a highly perishable fruit whose characteristics make it susceptible to developing microorganisms. Plant extracts have been studied as an alternative to pesticides to control spoilage microorganisms, responding to the expectation of the population seeking a healthier way of life. The fungus Botrytis cinerea is a facultative pathogen of vegetables, which can affect all stages of the development of several fruits, such as the strawberry, where it causes gray rot. Trichilia catigua (catuaba), Paullinia cupana (guarana), Stryphnodendron barbatiman (barbatimão), and Caesalpinia peltophoroides (sibipiruna) are planted in the Brazilian flora and have demonstrated pharmacological properties in their extracts. This work aimed to treat strawberries with a biodegradable film containing extracts of these species to evaluate strawberry conservation. There were notable distinctions in mass loss between the extract-treated and control samples. The pH, total acidity (TA), and soluble solids parameters exhibited consistently significant means across both sets of samples. Luminosity increased over the course of days in the color parameters, with the exception of strawberries coated with guarana. The red color showed greater intensity, except for those coated with barbatimão extract. Considering the results, it is possible to conclude that the coatings used can become an alternative to enhance the conservation of strawberries.


Assuntos
Fragaria , Extratos Vegetais , Fragaria/química , Fragaria/microbiologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Botrytis/efeitos dos fármacos , Paullinia/química , Caesalpinia/química , Frutas/química
2.
Psychon Bull Rev ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383840

RESUMO

In contrast to language production, there are few comprehension models of the representation and use of grammatical gender in long-term memory. To bridge this gap, we conducted a systematic review of empirical studies on the role of gender-form regularities in the recognition of nouns in isolation and within sentences. The results of a final sample of 40 studies suggest that there are two routes for the retrieval of gender during real-time comprehension: a form-based route and a lexical-based route. Our review indicates that the use of these routes depends on the degree of gender transparency of the language and the degree of overtness of the experimental paradigm. To accommodate these findings, we incorporate a dual-route mechanism within a general model of lexical access in comprehension, the AUSTRAL (Activation Using Structurally Tiered Representations and Lemmas) model, and identify directions for future research.

3.
Rev Sci Instrum ; 91(5): 053301, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32486736

RESUMO

This work describes the new facility for applied nuclear physics at the University of Sao Paulo, mainly for irradiation of electronic devices. It is a setup composed of a quadrupole doublet for beam focusing/defocusing plus multiple scattering through gold foils to produce low intensity, large-area, and high-uniformity heavy-ion beams from 1H to 107Ag. Beam intensities can be easily adjusted from 102 particles cm2/s to hundreds of nA for an area as large as 2.0 cm2 and uniformity better than 90%. Its irradiation chamber has a high-precision motorized stage, and the system is controlled by a LabViewTM environment, allowing measurement automation. Design considerations and examples of use are presented.

4.
Appl Radiat Isot ; 152: 78-85, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31280111

RESUMO

This work presents the development of a portable system that allows 2D elemental mapping of large areas (maximum of 35.0 × 35.0 cm2) by XRF. A measuring head, composed of an x-ray source and a detector, is mounted on a 3-axis stage with movement reproducibility better that 0.03 mm. The final elemental map resolution of 1.4 mm was experimentally determined in the best condition of collimation, and the same experiments indicate that the resolution is fully dominated by the x-ray beam spot size. The main goal of this new setup is to perform analyses of historical, archaeological and geological objects. Because it's lightweight, our setup has the potential to be of great utility for in situ analyses, given the great difficulty and high costs transporting the artifacts from the museum to a laboratory. The importance of this instrumentation is related to the need to identify the distribution of the chemical elements in large surface areas of cultural heritage objects by a nondestructive method.

5.
Can J Physiol Pharmacol ; 83(2): 142-51, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15791287

RESUMO

Fetal and neonatal pancreatic islets present a lower insulin secretory response as compared with adult islets. Prolonged culturing leads to an improvement of the glucose-induced insulin secretion response in neonatal pancreatic islets that may involve regulation of gap junction mediated cell communication. In this study, we investigated the effect of culturing neonatal islet cells for varying periods of time and with different glucose medium concentrations on the cellular expression of the endocrine pancreatic gap junction associated connexin (Cx) 36 and Cx43. We report here that the 7-d culture induced upregulation of the expression of these junctional proteins in neonatal islets in a time-dependent manner. A correlation was observed between the increased mRNA and protein expression of Cx36 and Cx43 and the increased insulin secretion following islet culturing. In addition, increasing glucose concentration within the culture medium induced a concentration-dependent enhancement of Cx36 islet expression, but not of Cx43 expression in cultured neonatal islets. In conclusion, we suggest that the regulation of gap junctional proteins by culture medium containing factors and glucose may be an important event for the maturation process of beta cells observed at in vitro conditions.


Assuntos
Conexina 43/biossíntese , Conexinas/biossíntese , Ilhotas Pancreáticas/metabolismo , Animais , Animais Recém-Nascidos , Técnicas de Cultura de Células , Células Cultivadas , Conexina 43/genética , Conexinas/genética , Glucose/metabolismo , Insulina/metabolismo , Secreção de Insulina , RNA Mensageiro/biossíntese , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Regulação para Cima , Proteína delta-2 de Junções Comunicantes
6.
Pancreas ; 23(2): 177-85, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11484920

RESUMO

Fetal and neonatal pancreatic islets have lower insulin secretory responses compared with adult islets. In culture conditions and after treatment with mammosomatotropic hormones, neonatal islets undergo maturation of the secretory machinery that might involve regulation of cell-cell contacts within the islet. This study is an investigation of the effect of prolonged culturing and in vitro treatment with prolactin on the expression of the gap junction-associated connexin 43 and the adherens junction-associated beta-catenin in cultured neonatal rat islets. Pancreatic islets from neonatal Wistar rats were cultured for 24 hours or 7 days, and the treated group was exposed to 2 microg/mL prolactin daily for 7 days. Connexin 43 and beta-catenin were barely detected at the cell-cell contacts in 24-hour-cultured islets, as revealed by immunocytochemical analysis. Nevertheless, both junctional proteins were well expressed at the junctional region in islet cells cultured for 7 days and showed even greater staining in islets after long-term prolactin treatment. In accordance with the morphologic data, neonatal islets cultured for 24 hours displayed a relatively low level of connexin 43, as determined by Western blot analysis. Culturing for 7 days or combined prolactin treatment induced a significant increase in connexin 43 expression; this was 40% greater in the prolactin-treated group than in the control group. Furthermore, an enhancement of the expression of beta-catenin and translocation of this protein to the cell-cell contact site was also observed in neonatal islets cultured for 7 days compared with those cultured for 24 hours. In vitro prolactin treatment induced even greater expression of beta-catenin in islet cells. A correlation was observed between the increased expression of these junctional proteins and an increase in insulin secretion in cultured neonatal islets. In conclusion, prolonged culturing and in vitro treatment with prolactin induce the modulation of gap and adherens junctional proteins in pancreatic islets, which may be an important event in the in vitro maturation process of neonatal islet cells.


Assuntos
Conexina 43/metabolismo , Proteínas do Citoesqueleto/metabolismo , Ilhotas Pancreáticas/metabolismo , Transativadores , Animais , Animais Recém-Nascidos , Células Cultivadas , Imuno-Histoquímica , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Prolactina/farmacologia , Ratos , Fatores de Tempo , beta Catenina
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