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1.
Braz J Biol ; 83: e274032, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37937626

RESUMO

The rubber tree (Hevea brasiliensis (Willd. ex A.Juss.) Müll.Arg.), a native Amazonian species, is responsible for more than 50 thousand products and stands out as the world's main source of natural rubber. Commercial production is carried out by grafting, however, the technique has gaps in terms of time and quality for seedling production. Vegetative production via cuttings is an alternative, however, the species is difficult to root. Thus, the study tested the rooting induction, through a chemical method, with the hormonal regulator indolbutyric acid (IBA) of 5000 ppm, and a mechanical method, with the strangulation of stems, and the interaction between the methods, to analyze the survival and sprouting of rubber tree (Hevea brasiliensis) cuttings, as well as verifying the efficiency of breaking the sclerenchyma ring by strangulation. A randomized block design was used, with four treatments (control, with strangulation, with IBA, strangulation x IBA) distributed in six blocks with 36 cuttings. Data were submitted to ANOVA test and Tukey's post-test (p>0.05). The results obtained 12.5% of live cuttings, without rooting, during 68 days, being the combination of strangulation and IBA with greater survival and sprouting. No breakage of the sclerenchyma ring was observed by histological analysis. The data indicate strategic gains in combining chemical and mechanical techniques for species of difficult rooting in vegetative propagation, however, the test was not enough to affirm an answer in relation to each technique, the deepening of the technique on the behavior of the species remains the biggest challenge.


Assuntos
Hevea , Reprodução
2.
Braz J Biol ; 83: e268716, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37042910

RESUMO

Pre-emergent herbicides can contribute to the control of weed competition in direct seeding restoration, however it is necessary to evaluate their effects on seeds of native tropical forest species. The aim of the study was to assess the potential impact of the herbicide indaziflam on the germination of 17 forest species. For this, a dosage of 180 mL of the product in 200L of water was compared to the control without herbicide. The degree of sensitivity of each species was calculated by a ratio between the percentage of germination with herbicide (GH) and the control without herbicide (GC) classifying them as: extremely sensitive (ES= (GH/GC) <0.25), sensitive (S=0.25< (GH/GC) <0.50), low sensitivity (LS=0.50< (GH/GC) <0.75), indifferent (I=0.75< (GH/GC) <1.0) and potentiated (P= (GH/GC) >1). The herbicide promoted a significant reduction in mean germination in 35% (n=6) of the species and 59% (n = 10) were sensitive or extremely sensitive to indaziflam, and only three did not germinate. On the other hand, 29.4% (n=5) showed low sensitivity or indifference to the herbicide, while seed germination was slightly increased by indaziflam to 11.7% (n=2). Pre-emergent indaziflam can be recommended in direct seeding restoration, as only 17.6% (n=3) of the species were inhibited by pre-emergent. However, the effect of indaziflam varies by species and requires further studies to support large-scale use in direct seeding.


Assuntos
Germinação , Herbicidas , Sementes , Herbicidas/farmacologia , Florestas
3.
Mol Hum Reprod ; 17(2): 85-91, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20833870

RESUMO

Oocyte quality is one of the most important aspects of in vitro embryo development. Extensive epigenetic programming must occur during oocyte growth and maturation. A specific DNA methylation pattern of the imprinted genes must be established on differentially methylated regions (DMR). The insulin-like growth factor 2 (IGF2) gene is an important growth factor, and it is imprinted in several mammalian species. The aim of this study was to evaluate the methylation pattern on the DMR of the last exon of IGF2 in immature and mature bovine oocytes with different developmental competencies. Mature oocytes from large follicles were less methylated (28.93%) than immature oocytes from large follicles (77.38% P = 0.002), and there was also a tendency towards lower methylation in mature oocytes from large follicles (28.93%) compared with mature oocytes from small follicles (52.58% P = 0.07). Immature oocytes from small and large follicles showed 53.85% (7/13) and 91.66% (11/12) hypermethylated sequences, respectively, whereas mature oocytes from small and large follicles showed 61.11% (11/18) and 40% (4/10), respectively. The hypomethylation pattern in mature oocytes from large follicles may be related to the higher competence of these oocytes. Our results suggest that the methylation pattern in this DMR may be a useful parameter to investigate as a molecular marker for oocyte competence in cattle and as a model for studies in other species.


Assuntos
Metilação de DNA , Fator de Crescimento Insulin-Like II/química , Fator de Crescimento Insulin-Like II/genética , Oócitos/metabolismo , Animais , Bovinos , Células do Cúmulo , Epigênese Genética , Feminino , Sequência Rica em GC , Impressão Genômica , Folículo Ovariano , Reação em Cadeia da Polimerase
6.
Plant Biol (Stuttg) ; 21(3): 389-397, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-29779253

RESUMO

Large-scale restoration programmes in the tropics require large volumes of high quality, genetically diverse and locally adapted seeds from a large number of species. However, scarcity of native seeds is a critical restriction to achieve restoration targets. In this paper, we analyse three successful community-based networks that supply native seeds and seedlings for Brazilian Amazon and Cerrado restoration projects. In addition, we propose directions to promote local participation, legal, technical and commercialisation issues for up-scaling the market of native seeds for restoration with high quality and social justice. We argue that effective community-based restoration arrangements should follow some principles: (i) seed production must be based on real market demand; (ii) non-governmental and governmental organisations have a key role in supporting local organisation, legal requirements and selling processes; (iii) local ecological knowledge and labour should be valued, enabling local communities to promote large-scale seed production; (iv) applied research can help develop appropriate techniques and solve technical issues. The case studies from Brazil and principles presented here can be useful for the up-scaling restoration ecology efforts in many other parts of the world and especially in tropical countries where improving rural community income is a strategy for biodiversity conservation and restoration.


Assuntos
Sementes , Biodiversidade , Brasil , Conservação dos Recursos Naturais , Ecologia
7.
Braz J Biol ; 76(4): 955-966, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27166566

RESUMO

Ecological restoration aims to retrieve not only the structure but also the functionality of ecosystems. Frugivorous birds may play an important role in this process due to their efficiency in seed dispersal. Color perception in these animals is highly developed, and then the colors of fleshy fruits may provide important clues for choosing plant species for restoration plans. This study aims to integrate bird color preferences and restoration of degraded areas, with an objective to evaluate the potential attractiveness to birds by colored fruits. We carried out an experiment with 384 artificial fruits made of edible modeling clay with the following colors: black, blue, green and red, with 96 fruits of each color in six sites, including four restored areas and two second-growth forest fragments. We also tested the possible effect of light intensity on fruit consumption by color. A total of 120 (38.6%) were assumed to be consumed by birds, and the fruit consumption varied in response to the location and light incidence. Consumption of black and blue fruits was not related to site by chance. Notwithstanding, red and black fruits were consumed significantly more than any other colors, emphasizing bird preference to these colors, regardless of location. Enrichment with shade tolerant shrubs or forest species with black or red fruits may be an alternative way to manage established restorations. In recently established or new restorations, one may introduce pioneer shrubs or short-lived forest species which have blue fruits, but also those having black or red ones.


Assuntos
Aves , Cor , Recuperação e Remediação Ambiental , Preferências Alimentares , Florestas , Frutas , Animais , Brasil , Herbivoria , Pigmentação , Dispersão de Sementes
8.
Int Surg ; 83(2): 111-4, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9851325

RESUMO

BACKGROUND: In the surgical management of duodenal ulcers, the most feared complications are related to the treatment of the duodenal stump after Billroth lI-type gastric resections. Such complications are more evident in so-called 'difficult duodenum' cases, whose identification is directly related to the surgeon's experience. Among available techniques to avoid those complications, one is the treatment of the antralduodenal stump by the method of pre-pyloric exclusion and removal of antral mucosa, as proposed by Finsterer in 1918 and diffused by Bancroft in 1932. This method, however, was criticized, especially because of the possibility of retaining residual antral mucosa, which would be a determinant factor for the ulcer disease recurrence. The objective of the study was to verify whether the Finsterer-Bancroft operation is a valid alternative in the treatment of unresectable duodenal ulcers, as well as to encourage its application by less experienced surgeons, by the standardization of the surgical technique. METHODS: From April, 1984 to December, 1996 two hundred and six elective partial gastrectomies for duodenal ulcers were performed with Billroth II reconstruction. Of these, in thirty-one (15%), the Finsterer-Bancroft method was used. The patients' ages, varied between 23 and 65 years, constituting 25 males and 6 females. In all cases, surgery was indicated due to the presence of stenosis. RESULTS: Three patients (9.7%) had complications. There was one death (3.2%) due to leakage of duodenal stump and peritonitis, one case of duodenal fistula (3.2%), and one case of ulcer recurrence (3.2%). All three complications were caused by inappropriate application of the method. CONCLUSIONS: We conclude that the Finsterer-Bancroft operation is a valid alternative in the surgical treatment of chronic duodenal ulcers, when considered unresectable, and is within the reach of in-training and less experienced surgeons.


Assuntos
Úlcera Duodenal/cirurgia , Adulto , Idoso , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Duodeno/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Braz. j. biol ; 76(4): 955-966, Oct.-Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-828096

RESUMO

Abstract Ecological restoration aims to retrieve not only the structure but also the functionality of ecosystems. Frugivorous birds may play an important role in this process due to their efficiency in seed dispersal. Color perception in these animals is highly developed, and then the colors of fleshy fruits may provide important clues for choosing plant species for restoration plans. This study aims to integrate bird color preferences and restoration of degraded areas, with an objective to evaluate the potential attractiveness to birds by colored fruits. We carried out an experiment with 384 artificial fruits made of edible modeling clay with the following colors: black, blue, green and red, with 96 fruits of each color in six sites, including four restored areas and two second-growth forest fragments. We also tested the possible effect of light intensity on fruit consumption by color. A total of 120 (38.6%) were assumed to be consumed by birds, and the fruit consumption varied in response to the location and light incidence. Consumption of black and blue fruits was not related to site by chance. Notwithstanding, red and black fruits were consumed significantly more than any other colors, emphasizing bird preference to these colors, regardless of location. Enrichment with shade tolerant shrubs or forest species with black or red fruits may be an alternative way to manage established restorations. In recently established or new restorations, one may introduce pioneer shrubs or short-lived forest species which have blue fruits, but also those having black or red ones.


Resumo A restauração ecológica tem a finalidade de recuperar não apenas a estrutura, mas também a funcionalidade dos ecossistemas, e as aves frugívoras podem desempenhar um papel importante neste processo devido à sua eficiência na dispersão de sementes. Como a percepção da cor nestes animais é altamente desenvolvida, a cor dos frutos carnosos pode ser uma característica importante na escolha de espécies de plantas para os reflorestamentos. Este estudo tem como foco integrar a preferência de cor de frutos por aves e a recuperação de áreas degradadas, objetivando determinar a atratividade potencial de aves por frutos de cores diferentes. Foi realizado um experimento com 384 frutos artificiais feitos com massa de modelar comestível nas cores preta, azul, verde e vermelha, com um total de 96 frutos em cada cor em seis locais, incluindo quatro áreas restauradas e dois fragmentos de floresta secundária. Também foi testado o possível efeito da intensidade de luz sobre o consumo de frutos conforme as cores. Um total de 120 (38,6%) frutos foi considerado consumido pelas aves, e o consumo variou em resposta aos locais e incidência de luz. O consumo de frutos pretos e azuis foi significativamente relacionado com o local. Os frutos vermelhos e pretos foram significativamente mais consumidos do que as outras cores, enfatizando a preferência aves por essas cores, independentemente do local. O enriquecimento com espécies tolerantes à sombra com frutos pretos ou vermelhos pode ser uma alternativa para manejo de restaurações já estabelecidos; enquanto nos recentemente criados podem ser introduzidas espécies pioneiras ou florestais de vida curta com frutos azuis, pretos ou vermelhos.


Assuntos
Animais , Aves , Florestas , Cor , Recuperação e Remediação Ambiental , Preferências Alimentares , Frutas , Brasil , Pigmentação , Dispersão de Sementes , Herbivoria
10.
Arq. bras. med. vet. zootec ; 67(2): 555-563, Mar-Apr/2015. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: lil-747056

RESUMO

The aim of this study was to determine the nutritional requirements of energy and protein for maintenance and weight gain of crossbred cattle, as well as their efficiencies. Fifty 3/4 Zebu × 1/4 Holstein crossbred bulls with initial weights of 214±4kg and aged 11±0.2 months on average were used in this experiment. Four animals were used in the reference group; ten bulls were fed at the maintenance level; and the remaining 36 bulls were fed ad libitum and distributed in a completely randomized design in a 3×3 factorial arrangement, which had three feedlot periods (56, 112 or 168 days) and three calcium and phosphorus levels (low, medium and normal) in the diet. Four of the maintenance animals had their heat production measured by respirometry at the Laboratory of Metabolism and Calorimetry of UFMG. After slaughter, composite samples, referred to as carcass and noncarcass samples were obtained from each animal. The net energy requirements for maintenance (NEm) and metabolizable energy for maintenance (MEm) were 68.9 and 90.1 kcal/EBW0.75/day, respectively. The efficiency (km) was 76.41%. The NEm requirement determined in the respirometry chamber was 85.5 kcal/kg0.75. The following equations were obtained for net energy for gain (NEg) and net protein for gain (NPg): NEg (Mcal/day) = 0.0505±0.000986 × EBW0.75× EBWG1.095 and NPg (g/day) = 162.79±18.2546 × EBWG - 1.30±5.3010 × RE. The efficiencies of fat and protein deposition were 70.04 and 15.12%, respectively. In conclusion, the requirements of NEm for growing and finishing non-castrated 3/4 Zebu × 1/4 Holstein crossbred cattle are 68.9 kcal/EBW0.75/day. Requirements of NEg and NPg can be obtained by the following equations: NEg (Mcal/day) = 0.05050.000986 × EBW0.75 × EBWG1.095 and NPg (g/day) = 162.79±18.2546 × EBWG - 1.30±5.3010× RE.(AU)


Objetivou-se determinar as exigências nutricionais de energia e proteína para mantença e ganho de peso de bovinos cruzados, bem como suas eficiências. Foram utilizados 50 bovinos cruzados 3/4 Zebu × 1/4 Holandês, não castrados, com peso inicial de 214±4kg e idade média de 11±0,2 meses. Quatro animais foram usados para referência, dez para o grupo mantença e os 36 animais alimentados à vontade foram distribuídos em delineamento inteiramente ao acaso em esquema fatorial 3×3, sendo três períodos de confinamento (56, 112 ou 168 dias) e três níveis de cálcio e fósforo (baixo, médio e normal) na dieta. Quatro dos animais mantença foram encaminhados ao laboratório de metabolismo e calorimetria da UFMG para medição da produção de calor através da respirometria. Após os abates, foram obtidas duas amostras compostas para cada animal, denominadas carcaça e não carcaça. As exigências de energia líquida para mantença (ELm) e energia metabolizável para mantença (EMm) foram, respectivamente, de 68,9 e 90,1kcal/PCVZ0,75/dia. A eficiência (km) foi de 76,41%. A exigência de ELm obtida na câmara respirométrica foi de 85,5kcal/kg0,75. As equações obtidas para energia líquida de ganho (ELg) e proteína líquida de ganho (PLg) foram: ELg (Mcal/dia) = 0,0505±0,000986 × PCVZ 0,75 × GPCVZ 1,095 e PLg (g/dia) = 162,79±18,2546 × GPCVZ - 1,30±5,3010 × ER. As eficiências para deposição de gordura e de proteína foram de 70,04 e 15,12%, respectivamente. Conclui-se que as exigências de ELm para bovinos cruzados 3/4 Zebu × 1/4 Holandês não castrados em crescimento e terminação são de 68,9kcal/PCVZ0,75/dia; e que as exigências de ELg e PLg podem ser obtidas pelas respectivas equações: ELg (Mcal/dia) = 0,0505±0,000986 × PCVZ 0,75 × GPCVZ 1,095 e PLg (g/dia) = 162,79±18,2546 × GPCVZ - 1,30±5,3010 × ER.(AU)


Assuntos
Animais , Bovinos , Minerais na Dieta/administração & dosagem , Cálcio da Dieta , Fósforo na Dieta , Necessidades Nutricionais , Fenômenos Fisiológicos da Nutrição Animal
18.
J Microsc ; 122(Pt 3): 295-300, 1981 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7241589

RESUMO

A simple method of obtaining analogue images from traced models of biological specimens is presented. It consists of the photographic defocusing of traced models and it is illustrated with negatively stained cylindrical forms of the ASFV; the black lines of the trace in the model correspond to the negative stain surrounding the viral morphological subunits as seen in the electron micrograph. The photographic defocusing is the means by which the traced model is filtered and is used to introduce grey levels on an otherwise black and white image. The right amount of defocusing is attained when the width of the trace of the model equals the width of the rim of the negative stain appearing between the morphological subunits in the electron micrograph.


Assuntos
Modelos Estruturais , Fotomicrografia/métodos , Vírus da Febre Suína Africana/ultraestrutura , Animais , Computadores , Microscopia Eletrônica , Óptica e Fotônica
19.
Pediatr Surg Int ; 13(2-3): 95-9, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9580417

RESUMO

Gastric inflammatory myofibroblastic proliferation (IMP) is an extremely rare entity in children, which to our knowledge has only been mentioned in case reports. We describe the ninth pediatric case and review the literature concerning the etiology, clinical and laboratory features, pathology, treatment, and outcome. There has been a predominance in preschool females. Abdominal pain, upper gastrointestinal hemorrhage, and an abdominal mass, either isolated or associated, have been the main clinical features. Iron-deficiency anemia has been a constant finding. Lesions are elevated and involve the full thickness of the gastric wall, usually with ulceration of the luminal surface; extragastric extension suggesting malignancy is frequent. Diagnosis is made by histology after surgical excision. There was no mortality directly related to gastric IMP, and only one case recurred after surgical excision. The pathogenesis is controversial, but the finding of Helicobacter pylori in our case may indicate an inflammatory origin. Awareness of this benign lesion and its mimicry of malignancy is important so that inappropriately aggressive therapy can be avoided.


Assuntos
Granuloma de Células Plasmáticas/patologia , Gastropatias/patologia , Divisão Celular , Criança , Feminino , Fibroblastos/patologia , Granuloma de Células Plasmáticas/cirurgia , Humanos , Gastropatias/cirurgia
20.
Reproduçäo ; 5(1): 47-8, 1990.
Artigo em Português | LILACS | ID: lil-123217

RESUMO

Os AA avaliaram o resultado da microcirurgia tubária em 196 casos operados na Clínica Ginecológica da Escola Paulista de Medicina, no período de 10 anos; de 1978 a 1987. Separam os casos de acordo com o tipo de cirurgia em Salpingostomia: 52 vezes; lise de aderências (salpingolise): 48; anastomose ístmico ístmica: 62 e reimplante tubo-uterino: 34. Descrevem as técnicas e concluem expondo seus resultados em termos de permeabilizaçäo e de gravidez. Afirmam que cerca de 25% dos casos resultam em gestaçäo, na média de todos os casos e especificam as porcentagens de cada tipo de cirurgia realizada


Assuntos
Humanos , Feminino , Gravidez , Adulto , Tubas Uterinas/cirurgia , Microcirurgia , Prognóstico , Estudos Retrospectivos
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