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1.
J Plant Physiol ; 210: 64-71, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28088087

RESUMO

In order to gain insights into the controversial ripening behavior of loquat fruits, in the present study we have analyzed the expression of three genes related to ethylene biosynthesis (ACS1, ACO1 and ACO2), two ethylene receptors (ERS1a and ERS1b), one signal transduction component (CTR1) and one transcription factor (EIL1) in peel and pulp of loquat fruit during natural ripening and also in fruits treated with ethylene (10µLL-1) and 1-MCP (10µLL-1), an ethylene action inhibitor. In fruits attached to or detached from the tree, a slight increase in ethylene production was detected at the yellow stage, but the respiration rate declined progressively during ripening. Accumulation of transcripts of ethylene biosynthetic genes did not correlate with changes in ethylene production, since the maximum accumulation of ACS1 and ACO1 mRNA was detected in fully coloured fruits. Expression of ethylene receptor and signaling genes followed a different pattern in peel and pulp tissues. After fruit detachment and incubation at 20°C for up to 6days, ACS1 mRNA slightly increased, ACO1 experienced a substantial increment and ACO2 declined. In the peel, these changes were advanced by exogenous ethylene and partially inhibited by 1-MCP. In the pulp, 1-MCP repressed most of the changes in the expression of biosynthetic genes, while ethylene had almost no effects. Expression of ethylene perception and signaling genes was barely affected by ethylene or 1-MCP. Collectively, a differential transcriptional regulation of ethylene biosynthetic genes operates in peel and pulp, and support the notion of non-climacteric ripening in loquat fruits. Ethylene action, however, appears to be required to sustain or maintain the expression of specific genes.


Assuntos
Eriobotrya/metabolismo , Etilenos/biossíntese , Proteínas de Plantas/metabolismo , Eriobotrya/genética , Eriobotrya/crescimento & desenvolvimento , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Análise de Sequência de DNA
2.
Food Sci Technol Int ; 16(2): 159-67, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21339131

RESUMO

The effects of storage temperature, inhibition of ethylene action by treatment with 1-methylcyclopropene (1-MCP) and ultra low oxygen (ULO) atmosphere on chilling injury (CI), fruit firmness and ethylene production in the astringent 'Rojo Brillante' persimmon fruit were investigated. CI symptoms were manifested as a very dramatic loss of firmness after fruit transfer from cold storage to shelf-life conditions (18 °C). During cold storage, fruit softening appeared more rapidly in fruit stored at the intermediate temperature of 10 °C than at 1 °C or 14.5 °C. Ethylene production increased with storage time at the chilling temperature (1 °C) but a sharp increase took place upon fruit transfer from 1 °C to ambient temperature. This ethylene increase was accompanied by a loss of fruit firmness associated with chilling damage development. A pre-treatment with the competitive inhibitor of ethylene action 1-MCP, at 1 µL/L, reduced firmness loss and mitigated CI damage but considerably increased ethylene production in fruit transferred to shelf-life conditions after a prolonged cold storage period. Collectively, these results suggest a role of ethylene in the reduction of flesh firmness and consequently in the induction of CI in persimmon fruit. Moreover, ethylene exerts a negative feedback regulation of cold-induced ethylene biosynthesis. Storage of 'Rojo Brillante' persimmon fruit under ULO (1.3-1.8% O2, v/v) atmosphere did not affect the incidence of CI but reduced fruit astringency, suggesting that ULO may be an alternative postharvest storage system for 'Rojo Brillante' persimmon fruit.


Assuntos
Ciclopropanos/metabolismo , Diospyros/química , Conservação de Alimentos/métodos , Oxigênio/metabolismo , Atmosfera , Temperatura Baixa , Resposta ao Choque Frio , Etilenos/biossíntese , Frutas/química
3.
Br J Ophthalmol ; 89(10): 1298-301, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16170120

RESUMO

AIM: To compare the results of the water drinking test between glaucomatous eyes with and without visual field progression. METHODS: Retrospective analysis of 76 eyes of 76 open angle glaucoma patients followed for a mean period of 26.0 (SD 13.8) months. Patients were submitted to the water drinking test at the beginning of the follow up period. Reliable achromatic automated perimetry tests performed during the studied period were used to characterise visual field progression. All subjects were under clinical therapy and had an intraocular pressure (IOP) lower than 17 mm Hg monitored by isolated measurements during the follow up period. The results of the water drinking test were compared between glaucomatous eyes with and without visual field progression. RESULTS: Twenty eight eyes reached definite visual field progression. There were no significant differences in the mean age, sex, race, basal IOP, number of antiglaucomatous drugs, initial mean deviation (MD), and corrected pattern standard deviation (CPSD) between eyes that showed visual field progression and the ones who did not progress. A significant difference of 1.9 (SD 0.6) mm Hg (p = 0.001, analysis of covariance; 95% CI 0.8 to 3.0) was observed between glaucomatous eyes that showed visual field deterioration and glaucomatous eyes that did not progress. A significant difference of 16.8% (SD 4.6%) in the mean percentage of IOP variation was also observed between the two groups (p<0.001, analysis of covariance; 95% CI 7.7 to 26.0). CONCLUSIONS: Mean IOP peak and percentage of IOP variation during water drinking test were significantly higher in patients with visual field progression compared with patients who did not progress.


Assuntos
Ingestão de Líquidos , Glaucoma de Ângulo Aberto/fisiopatologia , Campos Visuais , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/uso terapêutico , Ritmo Circadiano , Técnicas de Diagnóstico Oftalmológico , Progressão da Doença , Feminino , Seguimentos , Glaucoma de Ângulo Aberto/tratamento farmacológico , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Testes de Campo Visual
4.
J Agric Food Chem ; 49(12): 6020-5, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11743802

RESUMO

Low-temperature, nonfreezing, storage induces pitting and necrosis in the flavedo tissue of chilling susceptible citrus fruits. In this study the role of ethylene and phenylalanine ammonia-lyase (PAL; EC 4.3.1.5) in the cold-induced citrus peel damage has been investigated. It has been shown that increasing PAL activity by applying ethylene at a nonchilling temperature did not cause fruit damage or reduce the incidence of this peel disorder when fruits were subsequently held at a chilling temperature (2 degrees C). The cold-induced peel damage was enhanced by applying inhibitors of PAL activity and ethylene synthesis and action. These results indicate that the induction of PAL and ethylene during fruit cold storage, but not before, plays a role in reducing the development of chilling symptoms. The cold-induced PAL activity was reduced by inhibitors of ethylene production, but inhibitors of ethylene action exerted little effect on the activation of this enzyme. Therefore, the activation of PAL may be dependent on ethylene but also an independent cold signal apparently related to the cold-induced peel damage.


Assuntos
Citrus/enzimologia , Etilenos/farmacologia , Fenilalanina Amônia-Liase/metabolismo , Fenilalanina/análogos & derivados , Citrus/fisiologia , Temperatura Baixa , Etilenos/antagonistas & inibidores , Conservação de Alimentos/métodos , Cinética , Fenilalanina/farmacologia
5.
J Agric Food Chem ; 48(7): 2726-31, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10898613

RESUMO

The effects of different periods of heating at 37 degrees C on phenylalanine ammonia-lyase (PAL) and how this relates to chilling tolerance was investigated in fruits of the chilling-sensitive Fortune mandarin. All effective heat-conditioning treatments caused an early and transient increase in PAL mRNA and PAL activity. Conditioning fruits at 37 degrees C for 1 or 2 days prevented the manifestation of chilling symptoms but not the accumulation of PAL mRNA and PAL activity observed in untreated fruits. In fruits conditioned for 3 days, cold-induced damage and PAL activity were also suppressed but not the accumulation of PAL transcript upon subsequent storage at 2 degrees C. Storage of 3-day-heated fruits at a nonchilling temperature (12 degrees C) induced an early and transient increase in both PAL mRNA and PAL activity. High levels of PAL transcript and PAL activity were detected in freshly harvested fruits of a chilling-resistant mandarin (Hernandina) that decreased upon cold storage at 2 degrees C in heat-treated and nontreated fruits. These results indicate that sensitivity of mandarins to chilling correlates with low constitutive levels of PAL mRNA and PAL activity and with the inducibility of both upon exposure to low temperatures.


Assuntos
Citrus/enzimologia , Conservação de Alimentos , Fenilalanina Amônia-Liase/metabolismo , Temperatura Baixa , Temperatura Alta , Fenilalanina Amônia-Liase/biossíntese , Fenilalanina Amônia-Liase/genética , Transcrição Gênica
6.
Bol. méd. Hosp. Infant. Méx ; 52(7): 439-42, jul. 1995. ilus
Artigo em Espanhol | LILACS | ID: lil-161961

RESUMO

Introducción. La estenosis bronquial es una patología poco común, de etiología congénita o adquirida. La estenosis en las vías aéreas se localiza en la gran mayoría de los casos a nivel subglótico, es rara en tráquea y extaordinariamente rara en bronquios. Caso clínico. Femenino de 6 años de edad con antecedente de intubación endotraqueal en el período neonatal. Evolución asintomática. Padecimiento de 5 meses de evolución con tos progresiva, posteriormente fiebre. Hipoventilación basal derecha, vibraciones vocales disminuidas y estertores bronquioalveolares ipsilaterales. En telerradiografía de tórax opacidad basal derecha que borra el ángulo cardiofrénico y sobredistensión pulmonar derecha. Broncoscopia con estenosis de 75 por ciento de la luz bronquial del lado derecho. Tratamiento quirúrgico con toma y colocación de injerto de cartílago costal. Evolución a 2 años favorable. Conclusiones. La estenosis bronquial fue de origen probablemente adquirido y secundario a la intubación endotraqueal en el período neonatal. El tratamiento con aplicación de parche de cartílago es una técnica útil, con resultados satisfactorios y accesible en nuestro medio


Assuntos
Criança , Humanos , Feminino , Brônquios/lesões , Brônquios/cirurgia , Brônquios/transplante , Intubação Intratraqueal/efeitos adversos , Estenose Traqueal/etiologia , Estenose Traqueal/cirurgia , Transplante Autólogo/reabilitação
7.
Plant Physiol ; 99(4): 1575-81, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16669076

RESUMO

Satsuma (Citrus unshiu [Mak] Marc.) and Clementine (Citrus reticulata [Hort.] Ex. Tanaka, cv Oroval) are two species of seedless mandarins differing in their tendency to develop parthenocarpic fruits. Satsuma is a male-sterile cultivar that shows a high degree of natural parthenocarpy and a high fruit set. Seedless Clementine varieties are self-incompatible, and in the absence of cross-pollination show a very low ability to set fruit. The gibberellins (GAs) GA53, putative 17-OH-GA(53), GA(44), GA(17), GA(19), GA(20), GA(29), GA(1), 3-epi-GA(1), GA(8), GA(24), GA(9), and GA(4) have been identified from developing fruits of both species by full-scan combined gas chromatography-mass spectrometry. Using selected ion monitoring with [(2)H(2)]- and [(13)C]-labeled internal standards, the levels of GA(53), GA(44), GA(19), GA(20), GA(1), GA(8), GA(4), and GA(9) were determined in developing ovaries at anthesis and 7 days before and after anthesis, from both species. Except for GA8, levels of the 13-hydroxy-GAs were higher in Satsuma than in Clementine, and these differences were more prominent for developing young fruits. At petal fall, Satsuma had, on a nanograms per gram dry weight basis, higher levels of GA(53) (10.4x), GA(44) (13.9x), GA(19) (3.0x), GA(20) (11.2x), and GA(1) (2.0x). By contrast, levels of GA(8) were always higher in Clementine, whereas levels of GA(4) did not differ greatly. Levels of GA(9) were very low in both species. At petal fall, fruitlets of Satsuma and Clementine contained 65 and 13 picograms of GA(1), respectively. At this time, the application of 25 micrograms of paclobutrazol to fruits increased fruit abscission in both varieties. This effect was reversed by the simultaneous applications of 1 microgram of GA(3). GA(3) alone improved the set in Clementine (13x), but had little influence on Satsuma. Thus, seedless fruits of the self-incompatible Clementine mandarin may not have adequate GA levels for fruit set. Collectively, these results suggest that endogenous GA content in developing ovaries is the limiting factor controlling the parthenocarpic development of the fruits.

8.
Tex Heart Inst J ; 12(3): 269-74, 1985 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15227017

RESUMO

New glutaraldehyde-treated vascular prosthesis tubes of bovine pericardium were placed in the abdominal aortas of 29 mongrel dogs and observed for 30 to 540 days. Clinical evaluation was performed during follow-up, and histologic and arteriographic studies were done at the end of the study. Patency was shown by arteriography in 27 of 29 tubes (93.1%). Neoendothelialization was found in all grafts, and there was a mixed effect, characterized by both rejection and foreign body reaction in the prostheses from 180 days onward. Both the handling and consistency of the grafts were excellent for implantation. Graft procoagulation and animal anticoagulation were not necessary.

9.
Stud Fam Plann ; 15(3): 143-8, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6740731

RESUMO

Clinical trials of norethisterone enanthate (NET-EN), a long-acting, injectable progestogen, have demonstrated its short-term safety and effectiveness as a method of contraception in a controlled trial setting. Family planning programs interested in providing NET-EN need information on its efficacy and acceptability under usual field conditions. This first field study of NET-EN was conducted in family planning clinics in rural areas of Mexico. Women admitted to the study were followed up at two-month intervals to receive an injection of 200 milligrams of NET-EN, and to be asked about possible side effects of the drug. Among the 5,792 women recruited, the overall life-table discontinuation rate was 57.0 per 100 women at 12 months and 69.0 at 18 months. The single most common reason for discontinuation was amenorrhea, followed by bleeding problems. Women who were older and who already had several children were most likely to continue using NET-EN. Nine pregnancies were reported during the study, with a cumulative pregnancy rate of 0.3 per 100 women at 18 months. NET-EN appears to be an effective method of contraception that is acceptable to a substantial proportion of women from rural areas in Mexico who choose to use it, when it is provided through a national family planning program.


Assuntos
Ensaios Clínicos como Assunto , Anticoncepcionais Orais Sintéticos , Anticoncepcionais Orais , Noretindrona/análogos & derivados , Análise Atuarial , Adolescente , Adulto , Fatores Etários , Amenorreia/induzido quimicamente , Feminino , Humanos , México , Noretindrona/efeitos adversos , Cooperação do Paciente , Gravidez , População Rural
10.
Invest. med. int ; 9(4): 331-5, 1982.
Artigo em Espanhol | LILACS | ID: lil-12976

RESUMO

Se exponen las experiencias de mas de 10 anos con el empleo de un antitrombotico, dipiridamol, administrado a largo plazo (promedio 72 meses), en pacientes sujetos a cirugia por arteriopatia oclusiva arteriosclerotica o tromboembolica. Un grupo testigo, sin medicacion antitrombotica, sirve de control. El grupo A muestra una incidencia muy baja de fenomenos tromboembolicos, durante los periodos en que se administra el dipiridamol y alta incidencia cuando se suspende este medicamento.El grupo B, sin medicacion antitrombolica, presenta el segundo episodio oclusivo en mas del 50% de los pacientes


Assuntos
Adulto , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Arteriopatias Oclusivas , Arteriosclerose Obliterante , Dipiridamol , Tromboembolia
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