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1.
Cryo Letters ; 42(5): 290-299, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35363850

RESUMO

BACKGROUND: Pogostemon yatabeanus, synonym Dysophylla yatabeana, (Labiatae) is an endangered wild species in Korea. It has has a limited natural habitat and requires urgent conservation measures. OBJECTIVE: To develop an efficient cryopreservation protocol using in vitro shoot tips to complement traditional conservation approaches in case seeds are unavailable, or insufficient in number for conservation programs. MATERIALS AND METHODS: Node-cutting induced shoot tips of in vitro plants were produced and cryopreserved using a droplet-vitrification method following improvements in preculture, osmoprotection, vitrification solution (VS) and regrowth treatments. The starting protocol included preculture with 10% sucrose for 31 h, followed by osmoprotection with C4-35% (17.5% glycerol + 17.5% sucrose) for 40 min, and cryoprotection with A3-80% (33.3% glycerol + 13.3% DMSO + 13.3% EG + 20.1% sucrose) for 60 min on ice, cooling and warming using aluminum foil strips, and regrowth in MS hormone-free medium. RESULTS: Shoot tips of Pogostemon yatabeanus were sensitive to the osmotic stress evidenced by low survival after step-wise preculture with 17.5% sucrose and cryopreservation without osmoprotection. Among VS tested, including PVS2, PVS3 and their alternatives, A3-80% on ice for 60 min resulted in the highest post-cryopreservation survival (80%) and regeneration (20%). Post-cryopreservation regeneration significantly improved (up to 73%) by incubation of cryopreserved shoot tips on ammonium-free medium followed by GA X3-containing medium and medium without growth regulators. CONCLUSION: Cryopreservation of in vitro shoot tips using droplet-vitrification was developed as a complementary conservation approach for D. yatabeana. Adjustment of medium composition during the recovery stage was important for regeneration of healthy plants from both cryoprotected-control and cryopreserved shoot tips.


Assuntos
Compostos de Amônio , Pogostemon , Animais , Criopreservação/métodos , Criopreservação/veterinária , Crioprotetores/farmacologia , Espécies em Perigo de Extinção , Brotos de Planta , Vitrificação
2.
Cryo Letters ; 40(2): 113-122, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31017611

RESUMO

BACKGROUND: Aster altaicus var. uchiyamae Kitam is an endemic and endangered species in urgent need of a comprehensive conservation strategy. OBJECTIVE: To develop an efficient cryopreservation protocol using in vitro shoot tips to complement traditional conservation approaches in case seeds are not available or insufficient for conservation programs. METHODS: Shoot tips of in vitro plants were cryopreserved using a droplet-vitrification method following improvement of pre-culture, osmoprotection, vitrification solution (VS), unloading and post-culture treatments. The starting protocol included step-wise pre-culture with 10% and 17.5% sucrose for 55 h and 17 h, respectively, followed by osmoprotection with C4-35% (17.5% glycerol + 17.5% sucrose) for 30 min, and cryoprotection with B5-80% (40% glycerol + 40% sucrose) for 60 min. RESULTS: Shoot tips of A. altaicus were found to be moderately sensitive to the osmotic stress. Pre-culture and osmoprotection were not critical for the regeneration of cryopreserved explants when either of these treatments was applied. Osmoprotection with C4-35% on ice for 60 min followed by cryoprotection with A3-80%, a modified and diluted PVS2, on ice for 60 min resulted in the highest (65.3%) regeneration of cryopreserved shoot tips. Among alternative VSs tested, A3-80% and B5-80% were superior to PVS2 and PVS3 used under the same conditions. Step-wise recovery of shoot tips on ammonium-free medium followed by GA3-containing medium and medium without growth regulators were critical for the normal regeneration of both VS-treated and cryopreserved shoot tips. CONCLUSIONS: Cryopreservation of in vitro shoot tips using droplet-vitrification was developed as a complementary conservation approach for A. altaicus. Adjustment of the composition of regrowth media depending on recovery stage was important for the regeneration of healthy plants from cryopreserved shoot tips.


Assuntos
Aster , Criopreservação/métodos , Espécies em Perigo de Extinção , Brotos de Planta , Vitrificação , Animais , Crioprotetores , Sacarose
3.
Cryo Letters ; 36(5): 344-52, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26574682

RESUMO

BACKGROUND: Sweet potato is a staple food worldwide, but a problematic species in terms of long term storage, as it is not suitable for germplasm conservation. OBJECTIVE: This study aimed to develop cryopreservation protocols for sweet potato shoot tips based on a droplet-vitrification procedure. METHODS: As a standard procedure, sweet potato shoot tips were precultured in a liquid MS medium supplemented with 10% sucrose (S-10%) and 17.5% sucrose (S-17.5%) for 31 and 17 h, respectively. They were then osmoprotected with C4-35% (17.5% glycerol + 17.5% sucrose) for 50 min and cryoprotected with PVS3 (50% glycerol + 50% sucrose) for 60 min. A set of experiments was designed to investigate critical factors, i.e. stepwise sucrose preculture, osmoprotection, cryoprotection with PVS2- and PVS3-based vitrification solutions, and their combinational effect, as well as temperature alteration through placement in a cooling/rewarming container. RESULTS: Sucrose preculture was determined to be necessary for the adaptation of sweet potato shoot tips to cryoprotection with PVS3, and the highest post-thaw (LN) regeneration rate was observed in a preculture with S-10% for 31 h → S-17.5% for 17 h (19.0%). The effect of one-step or two-step osmoprotection was not significant on survival or regeneration of either the cryoprotected-control (LNC) or LN shoot tips. Responses of sweet potato shoot tips to osmoprotection and cryoprotection were linked to the level of sucrose preculture. The use of alumimium foil strips (droplet-vitrification) resulted in significantly higher LN survival (89.8%) and regeneration (19.0%), compared to those using cryovials (vitrification, 67.2% and 0%, respectively). LN regeneration increased by 67.5% when cryopreserved shoot tips were transferred to a new postculture medium. CONCLUSIONS: This study demonstrates that the combination of stepwise sucrose preculture with a higher final concentration (up to 17.5%), cryoprotection with PVS3 and cooling with foil strip is crucial to the regeneration of LN sweet potato shoot tips.


Assuntos
Criopreservação/métodos , Ipomoea batatas/fisiologia , Técnicas de Cultura de Células , Crioprotetores/farmacologia , Meios de Cultura/farmacologia , Glicerol/farmacologia , Ipomoea batatas/efeitos dos fármacos , Pressão Osmótica , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/fisiologia , Sacarose/farmacologia
4.
Cryo Letters ; 35(5): 377-84, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25397952

RESUMO

BACKGROUND: A comparison of different cryopreservation techniques should be based on the characteristics of both the methodology and the material in question using an optimized procedure. OBJECTIVE: This study aimed at developing an encapsulation-vitrification procedure for hairy roots of Rubia akane using alternative loading and vitrification solutions, based on the existing optimized droplet-vitrification procedure. MATERIALS AND METHODS: Encapsulated roots were first precultured in liquid medium with 10% sucrose for 3 days, then with 17.5 % sucrose for 1 day, after which they were osmoprotected with solution C6-40 % (20 % glycerol + 20 % sucrose) for 50 min, cryoprotected with solution A3-90 % (37.5 % glycerol + 15 % DMSO + 15 % EG + 22.5 % sucrose, w/v) on ice for 40 min, cooled and warmed in 2 ml cryovials, and unloaded in 35% sucrose solution for 60 min. RESULTS: Through the application of this procedure to aged-clustered roots, up to 97.5 % post-cryopreservation regeneration was observed. In our previous study, droplet-vitrification of hairy roots of R. akane resulted in 83.8 % post-rewarming regeneration following preculture with 10 % sucrose for 2 days and 17.5 % sucrose for 4-5 h, and osmoprotection with solution C4-35 % (17.5 % glycerol + 17.5 % sucrose) for 30 min, and cryoprotection with solution A3-70 % (29.2 % glycerol + 11.7 % DMSO + 11.7% EG + 17.4% sucrose, w/v) on ice for 20 min. In the present study, higher post-cryopreservation regeneration was observed by using a higher concentration of vitrification solution (A3-70 % → A3-90 %, B5-80 % → B1-100 %) and/or a longer cryoprotection duration (A3-70 % at room temperature (RT) for 8 min → 15-30 min, on ice for 20 min → 40-80 min; B5-80 % for 15 min → 30-60 min). CONCLUSION: Even though encapsulation provided some degree of protection from the cytotoxicity of vitrification solutions to cytotoxicity-sensitive R. akane hairy roots, an overall higher post-cryopreservation regrowth was obtained using the droplet-vitrification procedure under optimized conditions. This result implies that this sensitive material was not sufficiently cryoprotected, and thus, rapid cooling and warming using foil strips was more efficient than cryopreservation of encapsulated samples.


Assuntos
Criopreservação/métodos , Crioprotetores/metabolismo , Raízes de Plantas/fisiologia , Rubia/fisiologia , Vitrificação , Pressão Osmótica/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Rubia/efeitos dos fármacos , Rubia/crescimento & desenvolvimento
5.
Cryo Letters ; 33(6): 506-17, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23250410

RESUMO

A systematic approach using a set of 13 treatments was applied to develop a droplet-vitrification protocol for Rubia akane hairy roots, based on their responses to preculture, loading, dehydration and cooling/rewarming steps. The roots were very sensitive to osmotic stress induced by both preculture in liquid sucrose-enriched medium (up to 0.5 M sucrose) and by dehydration with highly concentrated vitrification solutions (VSs). Loading was necessary before dehydration of explants with VS, and the composition of the loading solution (LS) significantly affected their post-cryopreservation regeneration. Due to high sensitivity of roots to both chemical cytotoxicity and osmotic stress produced by VSs, cryoprotection with alternative VSs, i.e. B5-80 percent (40 percent glycerol + 40 percent sucrose, w/v) at room temperature for 15 min or with A3-70 percent (29.2 percent glycerol + 11.7 percent DMSO + 11.7 percent EG + 17.4 percent sucrose, w/v) at 0 degree C for 20 min ensured the highest post-cryopreservation regeneration. However, when using these solutions, endothermic peaks (enthalpies) with -2.9 and -5.8 J per gram fresh weight, respectively, were recorded by differential scanning calorimetry (DSC) during the rewarming phase. Droplet-vitrification using foil strips showed higher post-cryopreservation regeneration (86 percent) compared with vitrification in cryovials (59 percent), possibly due to the higher cooling and rewarming rates achieved with droplet-vitrification. The developed protocol was applied to hairy roots of five other species with minor modifications in explant type, the duration of the last subculture before explant excision, and the dehydration duration with VS B5-80 percent.


Assuntos
Criopreservação/métodos , Crioprotetores/metabolismo , Raízes de Plantas/fisiologia , Rubia/fisiologia , Vitrificação , Varredura Diferencial de Calorimetria , Dimetil Sulfóxido/metabolismo , Glicerol/metabolismo , Pressão Osmótica , Sacarose/metabolismo
6.
Cryo Letters ; 33(5): 402-10, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23224373

RESUMO

A cryopreservation protocol has been developed for embryogenic callus cultures of castor aralia (Kalopanax septemlobus), a deciduous tree which is widely used in oriental medicine and in landscape design. Three preculture treatments, four loading and six vitrification solutions were tested in a vitrification procedure. Preculture of embryogenic callus (EC) with high sucrose concentrations (up to 0.7 M) showed no effect on regrowth after cryopreservation. Loading for 20 min at ambient temperature improved regrowth of cryopreserved EC by 70-75 percent compared with non-loaded samples, regardless of the composition of the loading solution. Among vitrification solutions, the highest regrowth of 95-100 percent after cryopreservation was obtained after incubation of EC in a vitrification solution A3-80 percent comprising (w/v) 33.3 percent glycerol + 13.3 percent DMSO + 13.3 percent EG + 20.1 percent sucrose for 40 min at 0°C. Profiling of crystallization and recrystallization events using differential scanning calorimetry (DSC) confirmed that freezing injury was minimized in samples after loading and cryoprotection with this vitrification solution. Unlike many other papers, the droplet-vitrification protocol did not produce higher post-cryopreservation regrowth of Kalopanax EC, compared with the vitrification procedure. When samples are sufficiently cryoprotected during VS treatment, vitrification using cryovials may be preferred, since droplet-vitrification is more complex and requires skilled personnel. Cryopreserved callus grew rapidly and produced numerous somatic embryos, which developed similarly to embryos obtained from non-cryopreserved samples.


Assuntos
Criopreservação/métodos , Kalopanax/embriologia , Vitrificação , Varredura Diferencial de Calorimetria , Crioprotetores/química , Cristalização , Dimetil Sulfóxido/química , Glicerol/química , Kalopanax/crescimento & desenvolvimento , Sacarose/química
7.
Reproduction ; 144(5): 603-16, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22936286

RESUMO

Many seasonal breeders time their reproductive efforts to specific times of the year to ensure adequate resources for the production and care of young. For long-day (LD) breeders, females born before the summer solstice (LDs) reach sexual maturity quickly and often breed that same year, whereas females born after the summer solstice (short days (SDs)) may delay reproductive development to the following spring when environmental conditions are favorable for reproduction. In Siberian hamsters, development in SD is associated with structural and functional differences in the ovary compared with females held in LD, including a greater number of primordial follicles and an abundance of hypertrophied granulosa cells (HGCs), which are immunoreactive for anti-Müllerian hormone. The goal of this study was to determine whether SD-induced gonadotropin suppression is responsible for these phenotypic differences. Gonadotropin levels were suppressed in LD hamsters using the GNRH antagonist acyline. Conversely, to determine whether the SD ovarian phenotype is completely reversed by gonadotropin stimulation, recombinant human FSH (rhFSH) was administered. Our treatments were successful in mimicking FSH concentrations of the opposite photoperiod, but they did not produce a comparable change in the ovarian phenotype. Most notable was the lack of HGCs in the ovaries of acyline-treated LD females. Similarly, HGCs were maintained in the ovaries of SD females treated with rhFSH. Our data suggest that gonadotropins alone do not account for the SD ovarian phenotype. Future studies will determine whether SD-induced changes in other factors underlie these phenotypic changes.


Assuntos
Hormônio Foliculoestimulante/farmacologia , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Gonadotropinas/fisiologia , Ovário/fisiologia , Phodopus , Fotoperíodo , Animais , Hormônio Antimülleriano/análise , Cruzamento , Cricetinae , Feminino , Hormônio Foliculoestimulante Humano/farmacologia , Células da Granulosa/química , Células da Granulosa/citologia , Oligopeptídeos/farmacologia , Folículo Ovariano/anatomia & histologia , Ovário/anatomia & histologia , Proteínas Recombinantes , Estações do Ano , Maturidade Sexual
8.
Endoscopy ; 44(11): 1031-6, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23012217

RESUMO

BACKGROUND AND STUDY AIMS: Transanal endoscopic microsurgery (TEM) has been shown to be highly effective for early rectal cancer, and endoscopic submucosal dissection (ESD) has been introduced to treat noninvasive colorectal neoplasia. The aim of this study was to compare the outcomes of ESD and TEM for superficial early rectal cancer. PATIENTS AND METHODS: We retrospectively analyzed 63 patients with nonpolypoid rectal high grade dysplasia or submucosa-invading cancer who were treated with ESD or TEM, and compared clinical outcomes and safety between the treatment groups. RESULTS: 30 patients underwent ESD and 33 underwent TEM. For ESD compared with TEM, en bloc resection rates were 96.7% vs. 100% (P = 0.476) and R0 resection rates were 96.7 % vs. 97.0 % (P = 1.000). There were no cases of local recurrence or distant metastasis in either group. Antibiotics were required in 11 patients (36.7%) in the ESD group and 33 (100%) in the TEM group (P < 0.001). There was no difference in net procedure time although ESD was associated with shorter total procedure time and hospital stay than TEM, with mean (standard deviation [SD]) 84.0 (51.2) vs. 116.4 (58.5) min (P = 0.0023), and 3.6 (1.2) vs. 6.6 (3.5) days (P < 0.001), respectively. There were no significant differences in complications between the two groups. CONCLUSIONS: Both ESD and TEM are effective and oncologically safe for treating nonpolypoid rectal high grade dysplasia and submucosa-invading cancers. ESD has the additional advantages of minimal invasiveness and avoidance of anesthesia. Therefore, ESD could be recommended as a treatment option for superficial early rectal cancers.


Assuntos
Microcirurgia/métodos , Proctoscopia/métodos , Neoplasias Retais/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Complicações Pós-Operatórias , Lesões Pré-Cancerosas/cirurgia , Neoplasias Retais/patologia , Estudos Retrospectivos , Resultado do Tratamento
9.
Eur J Clin Nutr ; 65(11): 1250-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21697819

RESUMO

BACKGROUND/OBJECTIVES: This study was aimed to assess the beneficial effects on metabolic syndrome of functional yogurt NY-YP901 (Namyang Dairy Product Co. Ltd and Nutra R&BT Inc., Seoul, Korea) supplemented with mixture of Streptococcus thermophilus, Lactobacillus acidophilus, Bifidobacterium infantis and extra-ingredients containing Bifidobacterium breve (CBG-C2), Enterococcus faecalis FK-23, fibersol-2 and so on. SUBJECTS/METHODS: This study was designed as an 8-week randomized, double-blind, placebo-controlled, parallel study. Treatment and control groups consumed a functional yogurt NY-YP901 (150 ml) and a placebo yogurt twice a day, respectively, for 8 weeks. Body weight and body mass index (BMI), blood pressure, lipid profiles, fasting glucose with HbA1C and waist circumference were measured before and after treatment. Inclusion criteria were healthy individuals between the ages 20-65 years old who submitted an informed consent. RESULTS: During the period August 2009 to December 2009, 101 healthy participants (31 males and 70 females) finished the study. Treatment group were 53 individuals, and the control group were 48 individuals. In the treatment group consuming NY-YP901, statistically significant beneficial changes were observed in body weight (treatment group vs control group=-0.24±1.50 vs +0.64±1.39 kg, P<0.05), BMI (-0.10±0.58 vs +0.24±0.50 kg/m(2), P<0.05 ) and low-density lipoprotein (LDL)-cholesterol (-7.71±14.14 vs -0.43±15.32 mg/dl, P<0.05) after 8 weeks. The change in other parameters was not different between the treatment and the control groups. CONCLUSIONS: The functional yogurt NY-YP901 reduced LDL-cholesterol, body weight and BMI in the subjects at a 300-ml consumption daily for 8 weeks. From these findings, regular intake of functional yogurt NY-YP901 may be consequently related to improve metabolic syndrome.


Assuntos
Alimentos Formulados/microbiologia , Síndrome Metabólica/dietoterapia , Probióticos/uso terapêutico , Iogurte/microbiologia , Adulto , Bifidobacterium , Índice de Massa Corporal , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , LDL-Colesterol/sangue , Método Duplo-Cego , Enterococcus faecalis , Feminino , Alimentos Formulados/análise , Humanos , Lactobacillus acidophilus , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/fisiopatologia , Pessoa de Meia-Idade , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Polissacarídeos/administração & dosagem , Polissacarídeos/uso terapêutico , Probióticos/administração & dosagem , República da Coreia/epidemiologia , Risco , Streptococcus thermophilus , Redução de Peso , Iogurte/análise
10.
Cryo Letters ; 30(4): 291-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19789826

RESUMO

In plant vitrification protocols, the loading treatment, which involves treating the explants with a moderately concentrated cryoprotectant solution, precedes dehydration of explants with highly concentrated vitrification solutions in order to reduce the toxicity which can be induced by their direct exposure to such highly concentrated solutions. This study aimed at developing alternative loading solutions composed of mixtures of glycerol and sucrose at various concentrations. Differential scanning calorimetry runs of loading solutions and of loaded and dehydrated explants were performed to assay thermal events occurring during cooling and warming. These loading solutions were applied to two model species, viz. garlic and chrysanthemum which were cryopreserved using a droplet-vitrification procedure. The loading treatment proved to be beneficial to both garlic and chrysanthemum and increased recovery of cryopreserved explants. However, response to the loading solutions tested varied between the two model species employed: with garlic, all the loading solutions had a similar effect, whereas survival of chrysanthemum shoot tips was significantly influenced by the composition of the loading solution employed. A loading solution comprising 1.9 M glycerol and 0.5 M sucrose was the most effective. The loading treatment may thus act as an osmotic stress neutralizer and/or induce the physiological adaptation of tissues and cells, including membranes, to both dehydration and freezing.


Assuntos
Criopreservação/métodos , Crioprotetores/farmacologia , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/fisiologia , Chrysanthemum , Alho , Glicerol/farmacologia , Sacarose/farmacologia
11.
Bull Environ Contam Toxicol ; 83(6): 859-64, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19471846

RESUMO

In order to grasp the concentration distribution and identify sources of PCBs, air and soil samples around Sihwa and Banwol industrial area in Korea were analyzed. In result, the polychlorinated biphenyls (PCBs) concentration of air and soil was ranged from 2.08 to 5.82 ng/m3 (0.0686­1.01 pg WHO-TEQ/m3) and 2.43 to 274 ng/g dry (0.116­60.5 pg WHO-TEQ/g dry), respectively. Air and soil samples showed the very similar isomer composition pattern in each homologue by matrix, respectively. As a result of MLR for soil samples, the whole contribution rate of PCBs products (Aroclor) to soil was ~2 times higher than combustion.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/análise , Resíduos Industriais/análise , Bifenilos Policlorados/análise , Atmosfera/química , Análise por Conglomerados , Poluição Ambiental/estatística & dados numéricos , Cromatografia Gasosa-Espectrometria de Massas , Análise de Componente Principal , Solo/química
12.
Plant Cell Rep ; 21(12): 1194-8, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12910369

RESUMO

Scrophularia buergeriana Miq. (figwort) contains a diverse group of bioactive natural products and is used to treat a variety of ailments, including fever, constipation, neuritis, and laryngitis. A transformation protocol was established for S. buergeriana using Agrobacterium tumefaciens. Kanamycin-resistant plants were regenerated from leaf explants co-cultivated with A. tumefaciens strain GV3101. The shoot regeneration medium was supplemented with 2 mg l(-1) 6-benzylaminopurine and 70 mg l(-1) putrescine to improve the efficiency of organogenesis. Detection of the neomycin phosphotransferase gene, the presence of high levels of beta-glucuronidase (GUS) transcripts and enzyme activity, and the histochemical localization of GUS confirmed the genetic transformation of S. buergeriana. This work demonstrates the potential of using A. tumefaciens to efficiently transfer foreign genes into a commercially and culturally important Oriental medicinal plant.


Assuntos
Agrobacterium tumefaciens/genética , Scrophularia/genética , Transformação Genética , Plantas Geneticamente Modificadas , Plantas Medicinais , Sementes
13.
J Exp Bot ; 51(347): 1005-16, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10948228

RESUMO

An efficient protocol for the establishment of transgenic opium poppy (Papaver somniferum L.) and California poppy (Eschscholzia californica Cham.) root cultures using A. grobacterium rhizogenes is reported. Five strains of A. rhizogenes were tested for their ability to produce hairy roots on wounded opium poppy seedlings and California poppy embryogenic calli. Three of the strains induced hairy root formation on both species, whereas two others either caused the growth of tumorigenic calli or produced no response. To characterize the putative transgenic roots further, explant tissues were co-cultivated with the most effective A: rhizogenes strain (R1000) carrying the pBI121 binary vector. Except for the co-cultivation medium, all formulations included 50 mg l(-1) paromomycin to select for transformants and 200 mg l(-1) timentin to eliminate the Agrobacterium. Four weeks after infection, paromomycin-resistant roots appeared on 92-98% of explants maintained on hormone-free medium. Isolated hairy roots were propagated in liquid medium containing 1.0 mg l(-1) indole-3-acetic acid to promote rapid growth. Detection of the neomycin phosphotransferase gene, high levels of beta-glucuronidase (GUS) transcripts and enzyme activity, and GUS histochemical localization confirmed the integrative transformation of root cultures. Transgenic roots grew faster than wild-type roots, and California poppy roots grew more rapidly than those of opium poppy. With the exception of a less compact arrangement of epidermal cells and more root hairs, transformed roots of both species displayed anatomical features and benzylisoquinoline alkaloid profiles that were virtually identical to those of wild-type roots. Transgenic root cultures of opium poppy and California poppy are a simple, reliable and well-defined model system to investigate the molecular and metabolic regulation of benzylisoquinoline alkaloid biosynthesis, and to evaluate the genetic engineering potential of these important medicinal plants.


Assuntos
Papaver/genética , Raízes de Plantas/genética , Plantas Medicinais , Rhizobium/genética , Alcaloides/biossíntese , Northern Blotting , Técnicas de Cultura de Células , Genes Reporter , Glucuronidase/genética , Glucuronidase/metabolismo , Isoquinolinas/metabolismo , Papaver/metabolismo , Raízes de Plantas/citologia , Transformação Genética
14.
Plant Cell Rep ; 19(4): 421-426, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30754797

RESUMO

The development of a rapid protocol for high-efficiency somatic embryogenesis and plant regeneration from seed-derived embryogenic callus cultures of California poppy (Eschscholzia californica Cham.) is reported. The optimized procedure required less than 13 weeks from the initiation of seed cultures to the recovery of plantlets and involved the sequential transfer of cultures onto solid Murashige and Skoog basal medium containing three different combinations of growth regulators. All steps were performed at 25  °C. Friable primary callus was induced from seeds of E. californica cultured on medium supplemented with 1.0 mg l-1 2,4-dichlorophenoxyacetic acid. The primary callus was transferred to medium containing 1.0 mg l-1 1-naphthaleneacetic acid and 0.5 mg l-1 6-benzylaminopurine to establish embryogenic callus and promote somatic embryogenesis. Regenerated plantlets were recovered after the conversion of somatic embryos on medium containing 0.05 mg l-1 6-benzylaminopurine and showed normal development. Embryogenic callus was induced at a frequency of 85%, an average of 45 somatic embryos were produced per callus, 90% of the somatic embryos converted, and about 70% of the plantlets were recovered in soil. The growth rate of somatic embryo-derived shoots could be increased by gibberellic acid treatment, but the resulting plantlets were hyperhydritic.

15.
Plant Cell Rep ; 19(10): 1006-1012, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30754831

RESUMO

An efficient Agrobacterium-mediated protocol for the stable genetic transformation of Eschscholzia californica Cham. (California poppy) via somatic embryogenesis is reported. Excised cotyledons were co-cultivated with A. tumefaciens strain GV3101 carrying the pBI121 binary vector. Except for the co-cultivation medium, all formulations included 50 mg l-1 paromomycin as the selective agent and 200 mg l-1 timentin to eliminate the Agrobacterium. Four to five weeks after infection, paromomycin-resistant calli grew on 80% of explants in the presence of 2.0 mg l-1 1-naphthaleneacetic acid (NAA) and 0.1 mg l-1 6-benzylaminopurine (BAP). Calli were cultured on somatic embryogenesis induction medium containing 1.0 mg l-1 NAA and 0.5 mg l-1 BAP, and somatic embryos were visible on 30% of the paromomycin-resistant calli within 3-4 weeks. Three to four weeks after the somatic embryos were transferred to phytohormone-free plant regeneration medium, 32% converted to paromomycin-resistant plants. Detection of the neomycin phosphotransferase gene and high levels of ß-glucuronidase (GUS) mRNA and enzyme activity, and the cytohistochemical localization of GUS activity in all plant tissues confirmed the integrative transformation of the regenerated plants. The normal alkaloid profile of California poppy was unaffected by the transformation process; thus, the reported protocol could serve as a valuable tool to investigate the molecular and metabolic regulation of the benzophenanthridine alkaloid pathway.

16.
Bioorg Med Chem Lett ; 9(20): 2909-14, 1999 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-10571146

RESUMO

A series of 3-acyloxy-2-phenalkylpropyl amides and esters of homovanillic acid were designed and synthesized as vanilloid receptor agonists containing the three principal pharmacophores of resiniferatoxin. Amide analogues 23, 5 and 11 were found to be potent agonists in vanilloid receptor assay both for ligand binding and for activation.


Assuntos
Amidas/química , Ésteres/química , Ácido Homovanílico/análogos & derivados , Receptores de Droga/agonistas , Desenho de Fármacos , Ácido Homovanílico/síntese química , Ácido Homovanílico/farmacologia
17.
Plant Mol Biol ; 40(1): 121-31, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10394951

RESUMO

Tyrosine/dihydroxyphenylalanine decarboxylase (TYDC) and the berberine bridge enzyme (BBE) represent the entry point and a key branch point, respectively, in the biosynthesis of benzylisoquinoline alkaloids in select species of the Papaveraceae and Fumariaceae. Genomic clones for tydc7 and bbe1 from opium poppy (Papaver somniferum L.) were isolated. Deletion analysis of tydc7 and bbe1 5'-flanking regions revealed the location of putative regulatory domains necessary for expression of the beta-glucuronidase (gus) reporter gene in a transient assay system based on the microprojectile bombardment of cultured opium poppy cells. A 105-nucleotide region between -393 and -287 of the tydc7 5'-flanking region, and a 155-nucleotide region between -355 and -200 of the bbe1 5'-flanking region, were found to be essential for promoter activity. RNA gel blot analysis showed that tydc7 and bbe1 expression is induced in cultured opium poppy cells in response to wounding or treatment with a pathogen-derived elicitor. Time-courses for the induction of tydc7 and bbe1 mRNAs in wounded cells were nearly identical to those for GUS activity in cells bombarded with select promoter-gus constructs when the -393 to -287 region of tydc7, or the -355 to -200 region of bbe1, was present. Our data suggest that the wound signal caused by the entry of DNA-coated microcarriers into opium poppy cells was sufficient to induce tydc7 and bbe1 promoter activity, and that wound-responsive regulatory elements are located within domains identified by deletion analysis.


Assuntos
Alcaloides/biossíntese , Genes de Plantas , Oxirredutases N-Desmetilantes/genética , Papaver/genética , Plantas Medicinais , Regiões Promotoras Genéticas , Tirosina Descarboxilase/genética , Sequência de Aminoácidos , Sequência de Bases , Compostos de Benzil/metabolismo , Biolística , Técnicas de Cultura , Di-Hidroxifenilalanina/metabolismo , Regulação da Expressão Gênica de Plantas , Genes Reporter , Vetores Genéticos , Biblioteca Genômica , Isoquinolinas/metabolismo , Dados de Sequência Molecular , Papaver/enzimologia , Transformação Genética , Tirosina/metabolismo
18.
Exp Gerontol ; 27(2): 241-50, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1521597

RESUMO

Tests for the causal involvement of specific physiological mechanisms in the control of aging require evidence that these mechanisms can be used to increase longevity or reproductive lifespan. Selection for later reproduction in Drosophila has been shown to lead to increased longevity, as well as increased resistance to starvation and desiccation stresses. Selection for increased resistance to starvation and desiccation in Drosophila melanogaster is here shown to lead to increased longevity, indicating that alleles that increase stress resistance also may increase longevity. The responses of desiccation and starvation resistance to selection are partly independent of each other, indicating a multiplicity of physiological mechanisms involved in selectively postponed aging, and thus aging in general.


Assuntos
Longevidade/genética , Seleção Genética , Animais , Desidratação , Drosophila melanogaster , Feminino , Masculino , Inanição , Estresse Fisiológico
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