RESUMO
BACKGROUND: Cryopreservation opens new avenues in the field of genetic resource conservation, especially in recalcitrant seeded palms such as arecanut for which field genebanks are exposed to pest and disease attacks and natural calamities. It is only through cryopreservation that the safety of the conserved germplasm can be assured at a relatively low cost for extended periods. OBJECTIVE: The objective of this work was to standardize various aspects of arecanut pollen cryopreservation, viz. collection and desiccation of pollen, in vitro germination, viability and fecundity studies. MATERIALS AND METHODS: Pollens of three arecanut genotypes (Sumangala, Hirehalli Dwarf and Hirehalli Dwarf x Sumangala) were collected in December 2013-February 2014. In vitro viability tests were conducted using fresh and desiccated pollen. Desiccated pollen was cryopreserved by direct immersion in liquid nitrogen and cryostored for different durations (24 hours to 2 years). Viability and fertility studies were conducted using cryopreserved pollen. RESULTS: Pollen extraction was achieved from fully opened male flowers by desiccation at room temperature (33-34 degree C). A medium containing 2.5 g/L sucrose was found to be best for in vitro germination at room temperature. There was no significant difference in germination between desiccated and cryopreserved pollen whereas pollen tube length decreased significantly after cryopreservation. Fertility studies using HD x Sumangala pollen cryostored for various durations (1 month, 1 year and 2 years) showed the setting of 70, 43 and 62%, respectively. Normal nut set was observed using cryopreserved pollen. CONCLUSION: Pollen cryopreservation is a viable option for germplasm conservation and hybridization programmes in arecanut.
Assuntos
Areca/fisiologia , Criopreservação/métodos , Pólen/fisiologia , Areca/efeitos dos fármacos , Areca/genética , Dessecação , Fertilidade/efeitos dos fármacos , Genótipo , Germinação/efeitos dos fármacos , Germinação/fisiologia , Pólen/efeitos dos fármacos , Tubo Polínico/anatomia & histologia , Tubo Polínico/efeitos dos fármacos , Padrões de Referência , Sacarose/farmacologia , Temperatura , Sobrevivência de Tecidos/efeitos dos fármacosRESUMO
Three-component coupling of aldehydes, vinylcyclopropyl carbinols, and nitriles in the presence of 10 mol% TMSOTf at -40 to 0 °C in dichloromethane affords a novel class of (3-oxabicyclo[4.2.0]octanyl)amides in high yields with excellent selectivity, whereas (1-vinylcyclobutyl)methanol provides the corresponding (1-(5-aryltetrahydrofuran-3-yl)cyclobutyl)amides under similar conditions. This is the first report on the synthesis of oxabicycles through a sequential Prins/Wagner/Ritter process.
Assuntos
Amidas/síntese química , Química Orgânica/métodos , Furanos/síntese química , Amidas/química , Produtos Biológicos/síntese química , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Catálise , Furanos/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , EstereoisomerismoRESUMO
This report focuses on application of zinc oxide nanoparticles (ZnONPs) carrying phycomolecule ligands as a novel plant growth promoter aimed at increasing the crop productivity. The present investigation examined the effect of ZnONPs on plant growth characteristics, and associated biochemical changes in cotton (Gossypium hirsutum L.) following growth in a range of concentrations (25-200 mg L-l ZnONPs) in combination with 100 mM P in a hydroponic system. Treated plants registered an increase in growth and total biomass by 130.6% and 131%, respectively, over control. Results demonstrated a significant increase in the level of chlorophyll a (141.6%), b (134.7%), carotenoids (138.6%), and total soluble protein contents (179.4%); at the same time, a significant reduction (68%) in the level of malondialdehyde (MDA) in leaves with respect to control. Interestingly, a significant increase in superoxide dismutase (SOD, 264.2%), and peroxidase (POX, 182.8%) enzyme activities followed by a decrease in the catalase (CAT) activity, in response to above treatments. These results suggest that bioengineered ZnONPs interact with meristematic cells triggering biochemical pathways conducive to an accumulation of biomass. Further investigations will map out the mode of action involved in growth promotion.
Assuntos
Gossypium/efeitos dos fármacos , Nanopartículas Metálicas/administração & dosagem , Fósforo/farmacologia , Óxido de Zinco/farmacologia , Biomassa , Carotenoides/metabolismo , Catalase/metabolismo , Clorofila/metabolismo , Relação Dose-Resposta a Droga , Gossypium/crescimento & desenvolvimento , Gossypium/metabolismo , Hidroponia/métodos , Malondialdeído/metabolismo , Meristema/efeitos dos fármacos , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Peroxidase/metabolismo , Fósforo/química , Proteínas de Plantas/metabolismo , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Superóxido Dismutase/metabolismo , Propriedades de Superfície , Difração de Raios X , Óxido de Zinco/químicaRESUMO
OBJECTIVES: Ethanol extract of the stem of Bauhinia purpurea Linn. was subjected to analgesic and anti-inflammatory activities in animal models. MATERIALS AND METHODS: Albino Wistar rats and mice were the experimental animals respectively. Different CNS depressant paradigms like analgesic activity (determined by Eddy's hot plate method and acetic acid writhing method) and anti-inflammatory activity determined by carrageenan induced paw edema using plethysmometer in albino rats) were carried out, following the intra-peritoneal administration of ethanol extract of Bauhinia purpurea Linn. (BP) at the dose level of 50 mg/kg and 100 mg/kg. RESULTS: The analgesic and anti-inflammatory activities of ethanol extracts of BP were significant (P < 0.001). The maximum analgesic effect was observed at 120 min at the dose of 100 mg/kg (i.p.) and was comparable to that of standard analgin (150 mg/kg) and the percentage of edema inhibition effect was 46.4% and 77% for 50 mg/kg and 100 mg/kg (i.p) respectively. Anti-inflammatory activity was compared with standard Diclofenac sodium (5 mg/kg). CONCLUSION: Ethanol extract of Bauhinia purpurea has shown significant analgesic and anti-inflammatory activities at the dose of 100 mg/kg and was comparable with corresponding standard drugs. The activity was attributed to the presence of phytoconstituents in the tested extract.
RESUMO
Modulation of NK cell activity by various lymphokines is well documented. Freshly isolated NK cells exhibit natural cytotoxicity (NC) and antibody-dependent cellular cytotoxicity (ADCC) against certain targets. Upon stimulation with IL-2, the NK cells acquire lymphokine-activated killer (LAK) activity, which enables them to kill a wide variety of targets. Our results demonstrate that freshly isolated NK cells from tumor-bearing rats exhibit NK activity towards YAC-1, and ADCC activity towards AK-5 targets. Fresh NK cells did not lyse AK-5 targets in the absence of anti AK-5 antibody. However, in vitro culture of fresh NK cells in the presence of rat recombinant IL-2 (r-IL-2) over a period of 7 days resulted in complete loss of ADCC activity with concomitant acquisition of LAK activity on AK-5 tumor targets. The LAK and ADCC activities could be effectively distinguished based on our observation that monoclonal anti-rat ICAM-1 and anti-rat LFA-1 antibodies inhibited only LAK activity, but not ADCC activity, in addition, anti-AK-5 antiserum, but not purified anti-AK-5 antibody, inhibited LAK activity, suggesting that soluble ICAM-1 present in hyperimmune serum could be responsible for inhibition of LAK activity. The loss of ADCC activity upon culture of NK cells with rIL-2 was not observed when the cultures were grown on a macrophage feeder layer. In addition, NK cells retained their ADCC activity when cultures were supplemented with a combination of recombinant IL-2 and IL-12. However IL-2, IFN-gamma or IL-12 alone did not prevent the loss of ADCC activity, suggesting the requirement of a combination of these lymphokines for the maintainance of ADCC activity.
Assuntos
Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Células Matadoras Ativadas por Linfocina/efeitos dos fármacos , Células Matadoras Ativadas por Linfocina/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Linfocinas/farmacologia , Neoplasias Experimentais/imunologia , Animais , Citotoxicidade Imunológica , Técnicas In Vitro , Molécula 1 de Adesão Intercelular/metabolismo , Interferon gama/farmacologia , Interleucina-12/farmacologia , Interleucina-2/farmacologia , Antígeno-1 Associado à Função Linfocitária/metabolismo , Masculino , Regressão Neoplásica Espontânea/imunologia , Ratos , Ratos Wistar , Proteínas RecombinantesRESUMO
We have studied the role of cytokines in the spontaneous regression of AK-5 histiocytoma in syngeneic rats. Animals in which the tumour regresses show high levels of cytokines in the serum compared with animals which succumb to the tumour, and levels of IL-2, IL-4, IL-12, interferon-gamma (IFN-gamma) and tumour necrosis factor-alpha (TNF-alpha) are significantly higher in tumour tissue of the former. Thus there is an association between rejection of the tumour and the levels of cytokines present in the tumour mass. Our results also suggest a predominant Th1-type of response in those rats that display early tumour rejection.