Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Molecules ; 29(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38731426

RESUMO

The use of by-products as a source of bioactive compounds with economic added value is one of the objectives of a circular economy. The olive oil industry is a source of olive pomace as a by-product. The olive pomace used in the present study was the exhausted olive pomace, which is the by-product generated from the air drying and subsequent hexane extraction of residual oil from the olive pomace. The objective was to extract bioactive compounds remaining in this by-product. Various types of green extraction were used in the present study: solvent extraction (water and hydroalcoholic); ultrasound-assisted extraction; Ultra-Turrax-assisted extraction; and enzyme-assisted extraction (cellulase; viscoenzyme). The phenolic profile of each extract was determined using HPLC-DAD and the total phenolic content (TPC) and antioxidant activity (ABTS, DPPH, and ORAC) were determined as well. The results showed significant differences in the yield of extraction among the different methods used, with the enzyme-assisted, with or without ultrasound, extraction presenting the highest values. The ultrasound-assisted hydroethanolic extraction (USAHE) was the method that resulted in the highest content of the identified phenolic compounds: 2.021 ± 0.29 mg hydroxytyrosol/100 mg extract, 0.987 ± 0.09 mg tyrosol/100 mg extract, and 0.121 ± 0.005 mg catechol/100 mg extract. The conventional extraction with water at 50 °C produced the best results for TPC and antioxidant activity of the extracts. The extracts from the USAHE were able to inhibit Gram-positive bacteria, especially Bacillus cereus, showing 67.2% inhibition at 3% extract concentration.


Assuntos
Antioxidantes , Azeite de Oliva , Extratos Vegetais , Polifenóis , Azeite de Oliva/química , Polifenóis/isolamento & purificação , Polifenóis/química , Polifenóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Química Verde/métodos , Olea/química , Cromatografia Líquida de Alta Pressão/métodos , Solventes/química
2.
Foods ; 13(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38275685

RESUMO

The present review paper focuses on recent developments in edible films and coatings made of base compounds from biological sources, namely plants, animals, algae, and microorganisms. These sources include by-products, residues, and wastes from agro-food industries and sea products that contribute to sustainability concerns. Chitosan, derived from animal biological sources, such as crustacean exoskeletons, has been the most studied base compound over the past three years. Polysaccharides typically constitute no more than 3-5% of the film/coating base solution, with some exceptions, like Arabic gum. Proteins and lipids may be present in higher concentrations, such as zein and beeswax. This review also discusses the enrichment of these bio-based films and coatings with various functional and/or bioactive compounds to confer or enhance their functionalities, such as antimicrobial, antioxidant, and anti-enzymatic properties, as well as physical properties. Whenever possible, a comparative analysis among different formulations was performed. The results of the applications of these edible films and coatings to fruit and vegetable products are also described, including shelf life extension, inhibition of microbial growth, and prevention of oxidation. This review also explores novel types of packaging, such as active and intelligent packaging. The potential health benefits of edible films and coatings, as well as the biodegradability of films, are also discussed. Finally, this review addresses recent innovations in the edible films and coatings industry, including the use of nanotechnologies, aerogels, and probiotics, and provides future perspectives and the challenges that the sector is facing.

3.
Foods ; 12(1)2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36613248

RESUMO

The micro- and nanoencapsulation of bioactive compounds has resulted in a large improvement in the food, nutraceutical, pharmaceutical, and agriculture industries. These technologies serve, on one side, to protect, among others, vitamins, minerals, essential fatty acids, polyphenols, flavours, antimicrobials, colorants, and antioxidants, and, on the other hand, to control the release and assure the delivery of the bioactive compounds, targeting them to specific cells, tissues, or organs in the human body by improving their absorption/penetration through the gastrointestinal tract. The food industry has been applying nanotechnology in several ways to improve food texture, flavour, taste, nutrient bioavailability, and shelf life using nanostructures. The use of micro- and nanocapsules in food is an actual trend used mainly in the cereal, bakery, dairy, and beverage industries, as well as packaging and coating. The elaboration of bio capsules with high-value compounds from agro-industrial by-products is sustainable for the natural ecosystem and economically interesting from a circular economy perspective. This critical review presents the principal methodologies for performing micro- and nanoencapsulation, classifies them (top-down and/or bottom-up), and discusses the differences and advantages among them; the principal types of encapsulation systems; the natural plant sources, including agro-industrial by-products, of bioactive compounds with interest for the food industry to be encapsulated; the bioavailability of encapsulates; and the main techniques used to analyse micro- and nanocapsules. Research work on the use of encapsulated bioactive compounds, such as lycopene, hydroxytyrosol, and resveratrol, from agro-industrial by-products must be further reinforced, and it plays an important role, as it presents a high potential for the use of their antioxidant and/or antimicrobial activities in food applications and, therefore, in the food industry. The incorporation of these bioactive compounds in food is a challenge and must be evaluated, not only for their nutritional aspect, but also for the chemical safety of the ingredients. The potential use of these products is an available economical alternative towards a circular economy and, as a consequence, sustainability.

4.
Molecules ; 25(11)2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32526879

RESUMO

Nowadays, the food sector is highly concerned with environmental issues and foreseen to develop strategies to reduce waste and losses resulting from activities developed in the food system. An approach is to increment added value to the agro-industrial wastes, which might provide economic growth and environmental protection, contributing to a circular economy. Mushroom by-products represent a disposal problem, but they are also promising sources of important compounds, which may be used due to their functional and nutritional properties. Research has been developed in different fields to obtain value added solutions for the by-products generated during mushroom production and processing. Bioactive compounds have been obtained and applied in the development of nutraceutical and pharmaceutical formulations. Additionally, other applications have been explored and include animal feed, fertilizer, bioremediation, energy production, bio-based materials, cosmetics and cosmeceuticals. The main purpose of this review is to highlight the relevant composition of mushroom by-products and discuss their potential as a source of functional compounds and other applications. Future research needs to explore pilot and industrial scale extraction methods to understand the technological feasibility and the economic sustainability of the bioactive compounds extraction and valorization towards different applications.


Assuntos
Agaricales/química , Antioxidantes/química , Suplementos Nutricionais/análise , Preparações Farmacêuticas/química , Resíduos/análise , Animais , Composição de Medicamentos , Humanos , Valor Nutritivo
5.
J Fish Dis ; 42(3): 455-463, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30659615

RESUMO

Perkinsus spp. have been detected in various bivalve species from north-east Brazil. Santa Catarina is a South Brasil state with the highest national oyster production. Considering the pathogenicity of some Perkinsus spp., a study was carried out to survey perkinsosis in two oyster species cultured in this State, the mangrove oyster Crassostrea gasar and the Pacific oyster Crassostrea gigas. Sampling involved eight sites along the state coast, and oyster sampling was collected during the period between January 2013 and December 2014. For the detection of Perkinsus, Ray's fluid thioglycollate medium (RFTM) and histology were used, and for the identification of the species, PCR and DNA sequencing were used. Perkinsus spp. was found by RFTM in C. gigas and C. gasar from São Francisco do Sul. This pathology was also detected in C. gasar from Balneário Barra do Sul both, by RFTM and histology. Perkinsus marinus was identified in C. gigas and C. gasar from São Francisco do Sul and Perkinsus beihaiensis in C. gasar from Balneário Barra do Sul. This is the first report of P. marinus in C. gigas from South America. Results of this preliminary study suggest that both oyster species tolerate the species of Perkinsus identified, without suffering heavy lesions.


Assuntos
Alveolados/isolamento & purificação , Crassostrea/parasitologia , Infecções Protozoárias em Animais/epidemiologia , Alveolados/genética , Animais , Aquicultura , Brasil/epidemiologia , Reação em Cadeia da Polimerase/métodos , Infecções Protozoárias em Animais/parasitologia , Análise de Sequência de DNA/métodos
6.
An Acad Bras Cienc ; 90(2 suppl 1): 2011-2023, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30133569

RESUMO

We present two pollen diagrams from the semi-arid Caatinga of the Catimbau National Park, in Pernambuco and from a Mauritia palm forest in the Caatinga/Cerrado ecotone of southern Piauí, NE Brazil, spanning the last 10,000 cal. yrs BP and the last 1,750 cal yrs BP, respectively. These two records contain a signature of the local vegetation and permit the correlation of the pollen signal with regional climatic changes. The Catimbau record shows Zizyphus sp., a typical Caatinga taxon, in all three pollen zones indicating regional Caatinga vegetation and the predominance of local arboreal taxa adapted to high humidity from 10,000 to ca. 6,000 cal. yrs BP with a gradual tendency towards drier conditions revealed by a deposition hiatus between 6,000 to ca. 2,000 cal. yrs BP. This abrupt loss of sediments in both localities is interpreted as a consequence of the establishment of modern semi-arid climates. The subsequent return of humidity is signaled by increased sedimentation rates and 14C date inversions in agreement with high precipitation, revealed by σ18O ratios in speleothems from NE Brazil. Modern sediments deposited in the last 500 years reflect local conditions with the maintenance of humidity by geological faulting and surfacing water tables.


Assuntos
Sedimentos Geológicos , Paleontologia , Pólen , Brasil , Clima Desértico , Árvores
7.
Int J Legal Med ; 132(4): 1139-1149, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29248958

RESUMO

Estimating the forensic age of living individuals is ever more important in forensic practice, due to the ongoing increase of migratory flows, amongst other causes. Using the Greulich and Pyle method on a sample of 1150 individuals of the Spanish population (n = 560, 0-18 years for girls, and n = 590, 0-19 years for boys), the mean difference between the bone and chronological ages was obtained: 0.01 years (- 0.81, + 0.92) for girls and 0.33 years (- 1.15, + 0.34) for boys. For a same class of age and sex, the inherent variability was also evaluated: [Formula: see text] (0.41-1.25) for girls and [Formula: see text]years (0.36-1.76) for boys. To minimise systematic errors with regard to the reference population, adjustment factors are proposed for each age and sex. A sequential classification criterion based on decision trees is postulated to improve reliability in the prediction of maturity. Implementation of the decision criterion in three categories enables the doubtful individuals to be separated into the category of "undetermined" and to satisfactorily classify in the categories of "mature" and "under age": 0.96 (0.86-0.99) specificity; 1.00 (0.92-1.00) specificity; and 1.00 (0.92-1.00) predictive value.


Assuntos
Determinação da Idade pelo Esqueleto/métodos , Ossos da Mão/crescimento & desenvolvimento , Rádio (Anatomia)/crescimento & desenvolvimento , Ulna/crescimento & desenvolvimento , Adolescente , Calcificação Fisiológica , Criança , Pré-Escolar , Epífises/diagnóstico por imagem , Epífises/crescimento & desenvolvimento , Feminino , Antropologia Forense , Ossos da Mão/diagnóstico por imagem , Humanos , Lactente , Recém-Nascido , Masculino , Osteogênese , Rádio (Anatomia)/diagnóstico por imagem , Reprodutibilidade dos Testes , Espanha , Ulna/diagnóstico por imagem , Adulto Jovem
8.
J Food Sci Technol ; 54(10): 3152-3160, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28974800

RESUMO

The aim of the present work was to study the effect of the osmotic dehydration (OD) pre-treatment on the mass transfer kinetics and water activity (aw) of apple cubes during hot air drying. The adequacy of different mathematical models to describe the moisture content of the product during this process was also evaluated. Apple cubes were osmotically dehydrated with sucrose or sorbitol solutions at 60 °C, and then dried by air at 25-80 °C. Overall, the OD and rise of the air temperature resulted in an increased water loss rate and a reduction of the aw. The osmotic agent used in the OD was not relevant to the air drying kinetics, but the pre-treatment with sorbitol solutions produced dried samples with lower aw. Newton's, Page's, modified Page's, Henderson and Pabis', Two-term, Two-term exponential, Logarithmic, Midilli et al.'s models could describe the moisture content well during the air drying process.

10.
World J Microbiol Biotechnol ; 28(3): 1253-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22805845

RESUMO

The main objective of this study was to evaluate the stability of astaxanthin after drying and storage at different conditions during a 9-week period. Recovery of astaxanthin was evaluated by extracting pigments from the dried powders and analysing extracts by HPLC. The powders obtained were stored under different conditions of temperature and oxygen level and the effects on the degradation of astaxanthin were examined. Under the experimental conditions conducted in this study, the drying temperature that yielded the highest content of astaxanthin was 220°C, as the inlet, and 120°C, as the outlet temperature of the drying chamber. The best results were obtained for biomass dried at 180/110°C and stored at -21°C under nitrogen, with astaxanthin degradation lower than 10% after 9 weeks of storage. A reasonable preservation of astaxanthin can be achieved by conditions 180/80°C, -21°C nitrogen, 180/110°C, 21°C nitrogen, and 220/80°C, 21°C vacuum: the ratio of astaxanthin degradation is equal or inferior to 40%. In order to prevent astaxanthin degradation of Haematococcus pluvialis biomass, it is recommended the storage of the spray dried carotenized cells (180/110ºC) under nitrogen and -21°C.


Assuntos
Biomassa , Dessecação/métodos , Preservação Biológica/métodos , Volvocida/química , Cromatografia Líquida de Alta Pressão , Temperatura , Fatores de Tempo , Xantofilas/análise
11.
Rev Clin Esp ; 207(10): 510-20, 2007 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-17988599

RESUMO

The patients being treated in our health care system are becoming increasingly older and have a greater prevalence of chronic diseases. Due to these factors, these patients require greater and easier accessibility to the system as well as continuity of medical care. Collaboration between the different levels of health care has been instrumental in the success of the system and has produced changes in the hospital medical care protocol. Our hospital has developed a care model oriented towards the patient's needs, resulting in a higher grade of satisfaction among the medical professionals. In this paper, we have given a detailed description of part of our medical model, illustrating its different components and indicating several parameters of its evaluation. We have also reviewed the current state of the various models published on this topic. In summary, we believe that this medical care model presents a different approach to management that benefits patients, medical professionals and the health system alike.


Assuntos
Continuidade da Assistência ao Paciente , Hospitais , Atenção Primária à Saúde , Continuidade da Assistência ao Paciente/organização & administração , Humanos , Modelos Organizacionais , Avaliação de Programas e Projetos de Saúde
12.
Rev. clín. esp. (Ed. impr.) ; 207(10): 510-520, nov. 2007. tab
Artigo em Es | IBECS | ID: ibc-057845

RESUMO

Los pacientes atendidos en nuestro sistema sanitario tienen cada vez más edad y mayor prevalencia de enfermedades crónicas. Estas características de salud han condicionado que entre las expectativas de mayor relevancia de los pacientes, se indiquen la accesibilidad al sistema y la continuidad en los cuidados. La colaboración entre los distintos niveles asistenciales ha sido una herramienta reconocida que facilita la consecución de estas expectativas, provocando cambios en la organización del trabajo. Nuestro hospital ha desarrollado un modelo de atención sanitaria que ­en su orientación al enfermo­ facilita la colaboración entre los distintos niveles asistenciales, consiguiendo un grado de satisfacción de los profesionales elevado. En este trabajo se describe detalladamente parte del modelo, mostrando los elementos que lo caracterizan, indicando algunos parámetros de la evaluación de resultados y revisando la situación de los modelos de continuidad asistencial publicados. En resumen, consideramos que este sistema asistencial está dotado de elementos de gestión que permiten atender las expectativas de los usuarios, aportando beneficios para el paciente, el profesional y el sistema sanitario (AU)


The patients being treated in our health care system are becoming increasingly older and have a greater prevalence of chronic diseases. Due to these factors, these patients require greater and easier accessibility to the system as well as continuity of medical care. Collaboration between the different levels of health care has been instrumental in the success of the system and has produced changes in the hospital medical care protocol. Our hospital has developed a care model oriented towards the patient's needs, resulting in a higher grade of satisfaction among the medical professionals. In this paper, we have given a detailed description of part of our medical model, illustrating its different components and indicating several parameters of its evaluation. We have also reviewed the current state of the various models published on this topic. In summary, we believe that this medical care model presents a different approach to management that benefits patients, medical professionals and the health system alike (AU)


Assuntos
Humanos , Atenção Primária à Saúde/métodos , Departamentos Hospitalares/métodos , Comportamento Cooperativo , Assistência ao Paciente , Espanha , Avaliação de Programas e Projetos de Saúde
13.
Bioresour Technol ; 96(15): 1650-7, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16023567

RESUMO

The Chemical Analysis Laboratory under study weekly generates 46.5 L effluent with low pH (0.7), high COD concentration (6535 mg O2/L), sulphate (10390 mg/L) and heavy metals (213 mg Hg/L, 55 mg Cr/L, 28 mg Al/L, 22 mg Fe/L, 10mg Cu/L, 4 mg Ag/L). A treatment sequence has been proposed using a physical chemical step (coagulation/flocculation or chemical precipitation) followed by a biological step (anaerobic treatment). Removals of COD (18%), turbidity (76%) and heavy metals (64-99%) were attained only after adjusting pH to 6.5, without requiring the addition of Al2(SO4)3 and FeCl3. Due to the low COD:sulphate ratio (0.9-1.3), it was possible to efficiently operate the UASB reactor (at the biological step) only upon mixing the effluent with household wastewater. COD, sulphate and heavy metals removals of 60%, 23% and 78% to 100%, respectively, were attained for 30% effluent in the reactor feed. The results pointed to the need of a pretreatment step and mixing the effluent in household wastewater prior to the biological step. This alternative is feasible as this can be achieved using sanitary wastewater generated in the university campus.


Assuntos
Reatores Biológicos , Química Analítica , Laboratórios , Universidades , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Bactérias Anaeróbias/metabolismo , Brasil , Físico-Química/métodos , Metais Pesados/análise , Metais Pesados/metabolismo , Oxigênio/metabolismo , Eliminação de Resíduos Líquidos/instrumentação
14.
Meat Sci ; 61(4): 449-55, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22061076

RESUMO

Lactobacillus sake 2a is a bacteriocinogenic strain isolated from "lingüiça frescal", a Brazilian sausage. The combined effect of modified-atmosphere (MA) packaging (100% CO(2) and 50% CO(2)/50% N(2)) and addition of L. sake 2a on inhibition of growth of Listeria monocytogenes was evaluated in "lingüiça" stored at 6 °C. By the end of the first week, the inhibition of L. monocytogenes due to MA was significant (P⩽0.05) while the presence of L. sake 2a did not influence significantly the growth of the pathogen. After 14 days, a reduction of 1.3-1.4 log in counts of L. monocytogenes was observed in samples containing L. sake 2a only or MA packaged only, while a reduction of 3.5 log was detected in those submitted to both treatments. Results indicate that inhibition of L. monocytogenes in "lingüiça frescal" by the bacteriocinogenic L. sake 2a is enhanced by the packaging of the product in MA.

15.
Bioresour Technol ; 81(1): 61-9, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11710346

RESUMO

The anaerobic treatment of the wastewater from the meat processing industry was studied using a 7.2 1 UASB reactor. The reactor was equipped with an unconventional configuration of the three-phase separation system. The effluent was characterized in terms of pH (6.3-6.6), chemical oxygen demand (COD) (2,000-6,000 mg l(-1)), biochemical oxygen demand BOD5 (1,300-2,300 mg 1(-1)), fats (40-600 mg l(-1)) and total suspended solids (TSS) (850-6,300 mg l(-1)) The reactor operated continuously throughout 80 days with hydraulic retention time of 14, 18 and 22 h. The wastewater from Rezende Industrial was collected after it had gone through pretreatment (screening, flotation and equalization). COD, BOD and TSS reductions and the biogas production rate were the parameters considered in analyzing the efficiency of the process. The average production of biogas was 111 day(-1) (STP) for the three experimental runs. COD removal varied from 77% to 91% while BOD removal was 95%. The removal of total suspended solids varied from 81% to 86%. This fact supports optimal efficiency of the proposed three-phase separation system as well as the possibility of applying it to the treatment of industrial effluents.


Assuntos
Matadouros , Indústria de Embalagem de Carne , Eliminação de Resíduos Líquidos , Purificação da Água/métodos , Anaerobiose , Animais , Reatores Biológicos , Gases/análise , Esgotos/análise
16.
Rev. microbiol ; 30(4): 315-23, out.-dez. 1999. ilus, tab, graf
Artigo em Inglês | LILACS | ID: lil-286785

RESUMO

In this study we determined some properties of cholesterol oxidase from a "Brevibacterium" strain isolated from buffalo's milk and identified the cholesterol degradation products by bacterial cell. A small fraction of the enzyme synthesized by cells cultured in liquid medium for 7 days was released into the medium whereas a larger fraction remained boud to the cell membrane. The extraction of this fraction was efficiently accomplished in 1 mM phosphate buffer, pH 7.0, containing 0.7(per cent) Triton X-100. The enzyme stability under freezing and at 45ºC was imrproved by addition of 20(per cent) glycerol. The optimum tempereature and pH for the enzyme activity were 53ºC and 7.5, respectively. The only steroidal product from cholesterol oxidation by the microbial cell and by the crude extract of the membrane-bound enzyme was 4-colesten-3-one. Chromatographic analysis showed that minor no steroidal compounds as well as 4-colesten-3-one found in the enzyme in the buffer solution. Cholesterol oxidation by the membrane-bound enzyme was a first order reaction type


Assuntos
Brevibacterium/isolamento & purificação , Brevibacterium/enzimologia , Colesterol Oxidase/análise , Cromatografia , Técnicas Bacteriológicas
17.
Med Clin (Barc) ; 98(14): 521-6, 1992 Apr 11.
Artigo em Espanhol | MEDLINE | ID: mdl-1602849

RESUMO

BACKGROUND: Given the progressive increase in infectious endocarditis (IE) in intravenous drug addicts (IVDA) in the province of Cadiz the present study was designed with the aim of studying the epidemiologic and clinical characteristics of this disease in our environment. METHODS: One hundred fifty episodes of IE occurring in 133 IVDA admitted to 6 hospitals in the province of Cadiz were studied in an open, multicentric study with a protocol of gathering of common data. Well known diagnostic criteria were used for this process and a univariant technique was employed in the analysis of prognostic factors. RESULTS: Fifty-three percent of the episodes occurred in the county of Campo de Gibraltar and 32% in the area of the Bay of Cadiz. The increase of the disease has been progressive since 1984 and marked over the last two years. All the patients presented fever, abnormal chest radiography in 90% and the process was produced by Staphylococcus aureus in 88%. Echography was abnormal in 85% of the episodes and vegetation was identified in 75%. The IE was located as right in 90%, mixed in 5% and left in 5%. Surgical treatment was required in 4 patients. Mortality was of 9%. Mixed or left location (p = 0.00003) and the development of the respiratory distress syndrome of the adult (p = 0.00001) were significantly associated with greater mortality. CONCLUSIONS: Infectious endocarditis in intravenous drug addicts maintains a well defined pattern of clinical expressivity and presents identifiable factors of prognostic influence. The increase in its prevalence in the province of Cadiz is probably due to a parallel increase in the addiction to intravenous heroin in this area.


Assuntos
Endocardite Bacteriana/epidemiologia , Dependência de Heroína/epidemiologia , Abuso de Substâncias por Via Intravenosa/epidemiologia , Adolescente , Adulto , Endocardite Bacteriana/complicações , Endocardite Bacteriana/etiologia , Endocardite Bacteriana/microbiologia , Endocardite Bacteriana/terapia , Feminino , Dependência de Heroína/complicações , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Espanha/epidemiologia , Abuso de Substâncias por Via Intravenosa/complicações
18.
Biol Neonate ; 60(3-4): 258-72, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1665709

RESUMO

Adrenocorticotrophin (ACTH) effects on lung development were studied in sheep. ACTH was infused into 10 fetal lambs at 129 days of gestation at a rate of 29, 110 or 250 micrograms/day for 72 h, a time course which was independent of the mechanical and hormonal forces associated with labor. Lungs were compared with those of normal fetuses at term (day 147). ACTH accelerates maturation of components of lung structure toward term values. Different components of cytodifferentiation of the type II alveolar cell showed different levels of sensitivity. The degree of acceleration, not the nature of the changes, was influenced by dose.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Pulmão/embriologia , Glândulas Suprarrenais/anatomia & histologia , Animais , Peso Corporal/efeitos dos fármacos , Dióxido de Carbono/sangue , Relação Dose-Resposta a Droga , Feminino , Sangue Fetal/química , Hidrocortisona/análise , Concentração de Íons de Hidrogênio , Pulmão/efeitos dos fármacos , Pulmão/ultraestrutura , Medidas de Volume Pulmonar , Masculino , Troca Materno-Fetal , Microscopia Eletrônica , Tamanho do Órgão/efeitos dos fármacos , Oxigênio/sangue , Gravidez , Progesterona/sangue , Radioimunoensaio , Ovinos
19.
J Dev Physiol ; 6(4): 313-27, 1984 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6481108

RESUMO

The effect of fetal nephrectomy on lung development was studied in sheep. Fetal kidneys were removed early in the canalicular stage of lung development (95 to 99 days of pregnancy) and lung structure examined during the alveolar stage (125 to 134 days of gestation). Progesterone and estradiol 17 beta concentrations in maternal and fetal plasma were normal for gestational age, thus indicating that the ewes were not close to labour at the time the fetuses were removed. Mean body weight was significantly reduced in nephrectomized fetuses (P less than 0.05). Overall growth of the fetal lung was not markedly affected by fetal nephrectomy. However, compared to controls, alveolar airspaces were smaller in the cranial lobes of nephrectomized fetuses (P less than 0.05) and made up a smaller percentage of the parenchyma for the whole lung. There were fewer lamellar bodies per type 2 alveolar cell in nephrectomized fetuses (P less than 0.05), and more cells were without lamellar bodies (P less than 0.01). Umbilical venous thyroxin (T4) concentrations were lower in nephrectomized fetuses compared to control values (P less than 0.005). Plasma thyroxin concentration in nephrectomized fetuses correlated directly with thyroid weight (P less than 0.02). There was no significant difference in cortisol concentrations in maternal or fetal plasma or fetal tracheal fluid between the two groups. It is thus possible that the delayed lung development observed in nephrectomized fetuses was related to reduced thyroid activity.


Assuntos
Pulmão/embriologia , Nefrectomia , Animais , Estradiol/sangue , Feminino , Maturidade dos Órgãos Fetais , Hidrocortisona/sangue , Rim/embriologia , Pulmão/ultraestrutura , Microscopia Eletrônica , Tamanho do Órgão , Gravidez , Ovinos , Tiroxina/sangue
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...