Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Org Biomol Chem ; 16(1): 62-69, 2017 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-29098212

RESUMEN

3,7-Dihydroxytropolones (3,7-dHTs) are highly oxygenated troponoids that have been identified as lead compounds for several human diseases. To date, structure-function studies on these molecules have been limited due to a scarcity of synthetic methods for their preparation. New synthetic strategies towards structurally novel 3,7-dHTs would be valuable in further studying their therapeutic potential. Here we describe the successful adaptation of a [5 + 2] oxidopyrilium cycloaddition/ring-opening for 3,7-dHT synthesis, which we apply in the synthesis of a plausible biosynthetic intermediate to the natural products puberulic and puberulonic acid. We have also tested these new compounds in several biological assays related to human immunodeficiency virus (HIV), hepatitis B virus (HBV) and herpes simplex virus (HSV) in order to gain insight into structure-functional analysis related to antiviral troponoid development.


Asunto(s)
Antivirales/farmacología , VIH/efectos de los fármacos , Virus de la Hepatitis B/efectos de los fármacos , Simplexvirus/efectos de los fármacos , Tropolona/análogos & derivados , Antivirales/síntesis química , Antivirales/química , Relación Dosis-Respuesta a Droga , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Relación Estructura-Actividad , Tropolona/síntesis química , Tropolona/química , Tropolona/farmacología
2.
J Food Sci Technol ; 52(1): 161-70, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25593366

RESUMEN

Sapburn injury in mango is regarded as the most serious problem as it reduces the aesthetic appeal and downgrade the fruit quality with considerable economic losses. For the control of sapburn injury, physiologically mature mango fruits of cv. Chausa were harvested along with 5-8 cm stalk attached. Immediately after harvesting, fruits were de-stemmed and treated with different desapping agent solutions [calcium hydroxide (1 %), sodium hydroxide (1 %), alum (0.5 and 1 %)] by dipping them for 5 min. In control fruits, the pedicels were removed and sap was allowed to spread freely over the fruit surface. After treatment application, fruits were air-dried and stored at ambient condition (30 ± 2 °C) for 12 days. Among the treatments, fruits desapped with sodium hydroxide (1 %) showed significantly lower (7.6-fold) sapburn injury followed by alum (0.5 %) treatment than control. Respiration and ethylene evolution rates were also significantly suppressed and delayed with sodium hydroxide (1 %) treatment. Fruit firmness and functional properties like, antioxidant capacity, total carotenoids and total phenolics content were also found higher in sodium hydroxide (1 %) treated fruits. Pectin methyl esterase and polygalacturonase enzyme activity were recorded higher in fruits of control and calcium hydroxide treatment however; it was suppressed by sodium hydroxide and alum treatments. Fruit quality parameters like color, total soluble solids, titratable acidity and total sugars content were found higher in calcium hydroxide and sodium hydroxide treated fruits than control and alum treated fruits.

3.
J Food Sci Technol ; 51(1): 111-7, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24426055

RESUMEN

Functional properties (anthocyanins, antioxidant, ascorbic acid and tannin) and sensory score were determined in pomegranate fruits at two storage temperatures (3 and 5 °C) after treatment with 2 mM putrescine and 1 : 10 carnauba wax (carnauba wax : water). The treatments (putrescine and carnauba wax) were given by immersion method followed by storage up to 60 days. Both treatments retained significantly higher anthocyanins, antioxidant, ascorbic acid, tannin and sensory qualities as compared with control fruits under both the storage conditions. Combined application of putrescine + carnauba wax showed better response in retaining functional properties than putrescine treated or nontreated fruits. The impacts of putrescine and carnauba wax treatments were found more pronounced after 30 days at 3-5 °C storage temperature in retaining functional and sensory qualities. After 60 days of storage, putrescine + carnauba wax retained about 25% higher antioxidant activity both at 3 and 5 °C storage temperatures.

4.
J Food Sci Technol ; 50(3): 590-4, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24425958

RESUMEN

Effect of heat shrinkable films on shelf life and quality of apples under ambient conditions was studied. Fully mature Royal Delicious apples (starch index 2.5 on 4.0 point scale) were either shrink-wrapped in 3 heat shrinkable films like Cryovac (9 µ), polyolefin (13 µ) and LDPE (25 µ) or were not wrapped at all (control) and then stored at ambient conditions (22-28°C and 52-68% RH). Observations on physiological loss in weight (PLW), decay loss, firmness, juice recovery, total soluble solids (TSS), acidity, ascorbic acid content and overall sensory quality were recorded immediately before packing, and after packing at weekly intervals. Best results were obtained with Cryovac (9 µ) films, which exhibited least PLW (2.3%) and decay loss (2.8%) and higher juice recovery (65.2%) and TSS (16.4%) over other films or control. Apples wrapped in Cryovac films also had higher overall sensory acceptability (8.3 out of 9) over other films or control. These studies indicated that apples could be very well packed in Cryovac heat shrinkable films for about 35 days with least PLW or decay loss, and without any adverse effect on fruit quality.

5.
J Food Sci Technol ; 48(6): 763-8, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23572819

RESUMEN

Sapota fruits are highly perishable due to their climacteric nature. The rapid softening of fruits is primarily due to high activity of many oxidative enzymes and liberation of ethylene. Harvest maturity plays a crucial role in deciding the marketability of climacteric fruits in general. Attempt has been made to evaluate the response of ethylene absorbent on variable maturity groups of harvested Sapota cv. Kallipatti with the objective to delay the ripening during transit and extend its marketability during storage at ambient condition (27-32 °C & 65-75% R.H.). Harvested fruits having three different degree of ripeness (as maturity indices viz. mature, half-ripe and ripe) were packed with or without ethylene absorbent sachets (Bioconservación, France) in 10 kg CFB boxes and transported from Dahnu to Delhi covering a distant of approximately 2500 KM by truck on road along with conventional packaging as control. The fruits were evaluated immediately on arrival at Delhi and subsequently during storage for various physical, physiological, biochemical and decay parameters. Mature fruits with ethylene absorbent exhibited maximum delay in ripening, low ethylene liberation, weight loss and high fruit firmness. The response of ethylene absorbent to extend the marketability of ripe fruit was not significant.

6.
Am J Ind Med ; 53(8): 836-41, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20213748

RESUMEN

BACKGROUND: Exposure to methyl isocyanate and other toxic gases in Bhopal, India, on December 3, 1984 resulted in thousands of acute deaths, pregnancy loss and long-term effects. METHODS: From 1985 to 2007, we conducted successive surveys of vital status and health to determine whether the exposure of parents to toxic gases in the Bhopal incident affected the 5-year survival and anthropometric variables of their offspring. RESULTS: Initial 5-year mortality of offspring of exposed parents was very high. Male but not female offspring who were exposed to gases in utero or who were born to exposed parents were stunted in growth until puberty, which was followed by a period of accelerated growth. Results also suggest a post-puberty effect on head circumference of females exposed to gases in utero. CONCLUSION: Exposure of pregnant women to toxic gases in Bhopal in 1984 resulted in high pregnancy loss, increased first 5-year mortality and delayed development of male progeny.


Asunto(s)
Trastornos del Crecimiento/inducido químicamente , Isocianatos/toxicidad , Exposición Materna/efectos adversos , Exposición Paterna/efectos adversos , Plaguicidas/toxicidad , Efectos Tardíos de la Exposición Prenatal/epidemiología , Análisis de Varianza , Antropometría , Antidrepanocíticos/toxicidad , Estatura , Tamaño Corporal , Peso Corporal , Liberación de Peligros Químicos/estadística & datos numéricos , Preescolar , Femenino , Trastornos del Crecimiento/epidemiología , Estado de Salud , Encuestas Epidemiológicas , Humanos , India/epidemiología , Lactante , Mortalidad Infantil/tendencias , Recién Nacido , Masculino , Ápice del Flujo Espiratorio , Embarazo , Pubertad , Factores Sexuales , Estrés Fisiológico
7.
Indian J Pathol Microbiol ; 36(1): 45-7, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8354554

RESUMEN

Histopathological study of 10 cases sclerema neonatorum showed subcutaneous fibrosis with lobulation in all the cases. 8 (80 percent) cases showed non-specific chronic inflammation of dermis and thinning of epidermis with atrophy of rete pegs and hypercollgenisation of dermis was evident in 70 percent cases. Fat necrosis with crystallisation of fat content was not a conspicuous feature.


Asunto(s)
Esclerema Neonatal/patología , Tejido Adiposo/patología , Tamaño de la Célula , Epidermis/patología , Necrosis Grasa/patología , Muerte Fetal/patología , Humanos , Recién Nacido , Inflamación
9.
Plant Foods Hum Nutr ; 59(2): 67-72, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15678754

RESUMEN

Guava (Psidium guajava) fruits of cv. L-49 with individual shrink wrapping using 9 micro LLDPE film could be successfully stored up to 12 days at ambient and 18 days in evaporative cool chamber with negligible loss in vitamin C content. The untreated fruits lose 25-30% of ascorbic acid within 1 week after harvest. Delay in senescence and metabolic activities as supported by less changes in soluble solids, sugars, acidity, respiration, and ethylene evaluation rate was also observed in individual shrink wrapped fruits in cool chamber. The spoilage of fruits by Fusarium rots was significantly less in cool chamber in individually shrink wrapped fruits followed by Sta-fresh treatment. Sta-fresh was more effective in cool chamber than ambient. Individually stored wrapped fruits scored a better value of sensory score than Sta-fresh under both the storage condition.


Asunto(s)
Manipulación de Alimentos/métodos , Embalaje de Alimentos/métodos , Conservación de Alimentos/métodos , Psidium , Antioxidantes/análisis , Ácido Ascórbico/análisis , Comportamiento del Consumidor , Humanos , Valor Nutritivo , Gusto , Temperatura , Factores de Tiempo
10.
Carcinogenesis ; 2(12): 1345-52, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7326833

RESUMEN

In rat liver microsomal preparations, the 10,11-dihydrodiol of dibenz[a,c]anthracene (DBA) is metabolized to r-10,t-11-dihydroxy-t-12,13-oxy-10,11,12,13-tetrahydrodibenz[a,c]anthracene (anti-DBA 10,11-diol 12,13-oxide), the anti isomer of a non-bay-region diol-epoxide of DBA. When 3H-labelled DBA or trans-10,11-dihydro-10,11-dihydroxydibenz[a,c]anthracene were metabolized in this system in the presence of DNA or when 3H-labelled DBA was added to primary cultures of hamster embryo cells, covalent reactions of hydrocarbon metabolites with DNA occurred. The chromatographic characteristics of the radioactive hydrocarbon-deoxyribonucleoside adducts formed in these reactions were examined using Sephadex LH20 column chromatography and high pressure liquid chromatography. The results showed that whilst some of the radioactive hydrocarbon-deoxyribonucleoside adducts formed were indistinguishable from adducts that were formed when anti-DBA 10,11-diol 12,13-oxide reacted with DNA, other, unidentified adducts, which did not apparently arise from reactions of this diol-epoxide with DNA, were also present. Hydrocarbon-nucleoside adducts were not detected in hydrolysates of nucleic acids that were isolated from mouse skin that had been treated in vivo with DBA.


Asunto(s)
Benzo(a)Antracenos/metabolismo , ADN/metabolismo , Microsomas Hepáticos/metabolismo , Animales , Biotransformación , Células Cultivadas , Cromatografía Líquida de Alta Presión , Cricetinae , Embrión de Mamíferos , Mesocricetus , Ratones , Ratas , Piel/metabolismo , Espectrofotometría Ultravioleta
SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda