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1.
Biocell ; 32(1): 33-39, Apr. 2008. ilus, tab
Artículo en Inglés | LILACS | ID: lil-541120

RESUMEN

Tropical Ilex species have recalcitrant seeds. This work describes experiments demonstrating the feasibility of long-term conservation of Ilex brasiliensis, I. brevicuspis, I. dumosa, I. intergerrima, I. paraguariensis, I. pseudoboxus, I. taubertiana, and I. theezans through cryopreservation of zygotic rudimentary embryos at the heart developmental stage. The embryos were aseptically removed from the seeds and precultured (7 days) in the dark, at 27 +/- 2 degrees C on solidified (0.8% agar) 1/4MS medium, [consisting of quarter-strength salts and vitamins of Murashige and Skoog (1962) medium] with 3% sucrose and 0.1 mg/l Zeatin.The embryos were then encapsulated in 3% calcium alginate beads and pretreated at 24 h intervals in liquid medium supplemented with progressively increasing sucrose concentrations (0.5, 0.7 5 and 1 M). Beads were dehydrated for 5 h with silicagel to 25% water content (fresh weight basis) and then placed in sterile 5 ml cryovials. Then the beads were either plunged rapidly in liquid nitrogen were they were kept for 1 h (rapid cooling) or cooled at 1 degrees C min(-1) to -30 degrees C. Then the beads were immersed in liquid nitrogen for 1 h (slow cooling). The beads were rewarmed by immersion of the cryovials for 1 min in a water bath thermostated at 30 degrees C. Finally, beads were transferred onto culture medium (1/4MS, 3% sucrose, 0.1 mg/l zeatin, solidified with 0.8% agar) and incubated in a growth room at 27 +/- 2 degrees C under a 14 h light (116 micromol. m(-2) x s(-1))/ 10 h dark photoperiod. Maximum recovery percentages between 15 and 83% (depending on de the species and the treatment) were obtained with the cryopreserved embryos.


Asunto(s)
Supervivencia Celular , Criopreservación/métodos , Ilex/embriología , Ilex/fisiología , Semillas , Semillas/fisiología , Germinación , Técnicas de Cultivo de Tejidos
2.
Biocell ; 32(1): 33-39, Apr. 2008. ilus, tab
Artículo en Inglés | BINACIS | ID: bin-127186

RESUMEN

Tropical Ilex species have recalcitrant seeds. This work describes experiments demonstrating the feasibility of long-term conservation of Ilex brasiliensis, I. brevicuspis, I. dumosa, I. intergerrima, I. paraguariensis, I. pseudoboxus, I. taubertiana, and I. theezans through cryopreservation of zygotic rudimentary embryos at the heart developmental stage. The embryos were aseptically removed from the seeds and precultured (7 days) in the dark, at 27 +/- 2 degrees C on solidified (0.8% agar) 1/4MS medium, [consisting of quarter-strength salts and vitamins of Murashige and Skoog (1962) medium] with 3% sucrose and 0.1 mg/l Zeatin.The embryos were then encapsulated in 3% calcium alginate beads and pretreated at 24 h intervals in liquid medium supplemented with progressively increasing sucrose concentrations (0.5, 0.7 5 and 1 M). Beads were dehydrated for 5 h with silicagel to 25% water content (fresh weight basis) and then placed in sterile 5 ml cryovials. Then the beads were either plunged rapidly in liquid nitrogen were they were kept for 1 h (rapid cooling) or cooled at 1 degrees C min(-1) to -30 degrees C. Then the beads were immersed in liquid nitrogen for 1 h (slow cooling). The beads were rewarmed by immersion of the cryovials for 1 min in a water bath thermostated at 30 degrees C. Finally, beads were transferred onto culture medium (1/4MS, 3% sucrose, 0.1 mg/l zeatin, solidified with 0.8% agar) and incubated in a growth room at 27 +/- 2 degrees C under a 14 h light (116 micromol. m(-2) x s(-1))/ 10 h dark photoperiod. Maximum recovery percentages between 15 and 83% (depending on de the species and the treatment) were obtained with the cryopreserved embryos.(AU)


Asunto(s)
Supervivencia Celular , Criopreservación/métodos , Ilex/embriología , Ilex/fisiología , Semillas , Semillas/fisiología , Germinación , Técnicas de Cultivo de Tejidos
3.
Cryo Letters ; 27(4): 235-42, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16990951

RESUMEN

Encapsulation-dehydration was employed for cryopreserving seeds and in vitro-cultured protocorms of Oncidium bifolium. Freshly harvested seeds, 120 days after pollination, were encapsulated in beads containing 1/2 MS medium with 3% sucrose and 3% calcium alginate and subsequently pretreated in agitated (80 rpm) liquid medium supplemented with 0.15 M sucrose (24 h) followed by 0.25 M sucrose (48 h), 0.5 M sucrose (24 h) and 0.75 M sucrose (24 h). The beads with seeds were dehydrated with silica gel for 5 h to 19.2% moisture content and immersed in liquid nitrogen for 1 h, thawed at 30 degrees C for 2 min, post-treated using the same series of liquid media [0.5 M sucrose (24 h), 0.25 M sucrose (48 h), 0.15 M sucrose (24 h)], and recultured on 1/2 MS medium with 0.1M sucrose and 0.7% percent agar. As much as 4.8% of the cryopreserved seeds produced complete plants. In-vitro cultured protocorms were successfully cryopreserved following the same procedure, allowing 11.3% of them to produce plants.


Asunto(s)
Criopreservación/métodos , Orchidaceae/fisiología , Semillas/fisiología , Crioprotectores/farmacología , Deshidratación , Relación Dosis-Respuesta a Droga , Orchidaceae/efectos de los fármacos , Semillas/efectos de los fármacos , Gel de Sílice , Dióxido de Silicio , Sacarosa/farmacología
4.
Plant Cell Rep ; 19(9): 856-862, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30754920

RESUMEN

Plant regeneration in Arachis pintoi was obtained via two developmental pathways: organogenesis and somatic embryogenesis. Organogenic callus cultures were initiated from pieces of leaf on MS medium supplemented with NAA or 2,4-D in combination with BA, KIN or 2iP. The most suitable combination for plant regeneration through organogenesis was an initial medium composed of 10 mg/l NAA+1 mg/l BA followed by transfer of the callus to a shoot induction medium (MS+1 mg/l BA). Rooting of regenerated shoots was readily achieved by culture on MS+0.01 mg/l NAA. Embryogenic callus cultures were initiated from pieces of leaf on MS medium supplemented with PICL in combination with KIN, ZEA, BA or 2iP, and the most suitable combinations were 20 mg/l PICL+1 mg/l BA or 2iP. When pieces of embryogenic callus were subcultured on MS+1 mg/l BA, somatic embryos were differentiated and developed further into well-developed plants in MS+1 g/l AC followed by MS medium devoid of plant growth regulators.

5.
Qual Assur Health Care ; 3(3): 179-82, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1782385

RESUMEN

A program for automatic reading of medical prescriptions has been introduced in Friuli Venezia Giulia (Italy), to control the quality of medical care and the physicians' prescribing methods in office-based medical practice. Data on the prescribing practice of general practitioners, drug consumption and costs are collected, and then general practitioners are confidentially informed, through patient-specific medication profiles, on the number and costs of their prescriptions. The first data often showed inappropriate prescription practice on the part of doctors. Through this program an approach based on quality assurance principles is made possible to improve prescribing practice. Being "peer review" activities, bereft of fiscal or punitive ends, they are more readily acceptable by physicians who feel directly involved in improving the use of drugs, with positive connotations for containing costs.


Asunto(s)
Utilización de Medicamentos/estadística & datos numéricos , Medicina Familiar y Comunitaria/normas , Garantía de la Calidad de Atención de Salud , Costos de los Medicamentos , Prescripciones de Medicamentos/economía , Utilización de Medicamentos/economía , Utilización de Medicamentos/normas , Medicina Familiar y Comunitaria/economía , Italia , Pautas de la Práctica en Medicina/estadística & datos numéricos
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