The aim of present work was to investigate blends of Eudragit® NE 30D with Aquacoat® ECD using different ratios to eliminate curing effect associated with individual polymers. Propranolol HCl 10% w/w was layered onto sugar cores using 5% w/w HPMC as a binder. Drug-layered-cores were coated either with pure or blends of Aquacoat® ECD: Eudragit® NE 30D in a fluidized bed coater to obtain 20% w/w coating level. Talc 35% w/w was used as anti-tacking agent. The pellets were characterized for in vitro dissolution studies, morphology, water uptake-weight loss, osmolality and adhesion of coating after curing at 60 °C or 60 °C/75% RH for 24 h. The findings revealed that Aquacoat® ECD coated pellets showed curing effect due to further gradual coalescence of polymeric particles which resulted into better film formation upon curing. In contrast, the curing effect of Eudragit® NE 30D coated pellets was caused by decrease in adhesion of coatings after curing which provided entirely different swelling behavior of uncured (localized swelling) and cured (uniform swelling) pellets. The undesired curing effect of individual polymers was eliminated by using their blends in appropriate ratio.

Alzheimer disease (AD) is characterized by a low level of acetylcholine, beta-amyloid (Aβ) aggregation and oxidative stress. Donepezil is the core medicine used for the treatment of AD. Various structural modifications of donepezil have been carried out. Benzylpiperidine part of donepezil has been replaced with benzylpyridine, pyridyl methylpiperidine, benzylpiperazine, pyrimidyl piperazine. These derived molecules showed promising activities as anti-Alzheimer agents. Replacement of indanone part by other heterocyclic rings such as pyridine resulted in the formation of compounds which exhibited monoamine oxidase (MAO) as well as acetylcholinesterase (AChE) inhibition. Propargylamine containing derivatives displayed AChE as well as MAO inhibition properties. Attachment of donepezil with natural compounds like ferulic acid, flavonoids, and curcumin showed antioxidant activities in addition to inhibition of the AChE. Benzylpiperidine and benzylpiperazine have also been combined with condensed heterocyclic rings and these compounds displayed promising anti-Alzheimer properties. This review highlights the important structural modifications of donepezil and their influence on biological activities as anti-Alzheimer agents.

ABSTRACT Zidovudine was the first drug approved for the treatment of Acquired Immuno Deficiency Syndrome (AIDS). Its chemical name is azidothymidine (AZT). AZT use is associated with bone marrow toxicity. Shorter half-life and inability to penetrate the blood-brain barrier are the pharmacokinetic problems of this important drug molecule. Various modifications have been carried out in the structure of AZT. These include modification of hydroxyl and azido group, thymidine ring, preparation of phosphate and phosphonate derivatives, attachment of polymers and synthesis of hybrid molecules. Some of these changes produced compounds with significantly increased activity and less toxicity. This review highlights the various structural modifications of AZT and their influence on biological activities and pharmacokinetic properties.

RESUMO A emergência e o rendimento das culturas bulbosas ornamentais podem ser melhorados pela sua emergência no solo. A resposta do caládio a diferentes profundidades e datas de plantio foi pesquisada no Ornamental Horticulture Nursery, Departamento de Horticultura da Universidade de Agricultura de Peshawar durante o ano de 2008. O desenho de blocos completos randomizados em arranjo de parcelas subdivididas foi repetido três vezes. As épocas de semeadura (30 de março, 15 de abril e 30 de abril) foram distribuídas em parcelas principais enquanto as profundidades de plantio (2,5 cm, 5 cm, 7,5 cm e 10 cm) foram mantidas em subparcelas. Os resultados revelaram que os tubérculos de Caladium semeados em 30 de março levaram dias máximos para brotação (33), produziram o número máximo de brotos planta-1 (2,21), ganharam tamanho máximo de tubérculos (40,88 cm3) com alta produtividade de tubérculos (5.397 kg ha-1). Por outro lado, tubérculos semeados no dia 30 de abril levaram menos dias para brotar (20,21), produziram menos número de brotos planta-1 (1,53), produziram pequenos tubérculos (33,28 cm3) e a produção total de tubérculos também foi menor (4.374 kg ha-1). No caso da profundidade de plantio, tubérculos de caládio semeados a 7,5 cm de profundidade resultaram em altura máxima de plantas (52 cm), tamanho de tubérculos (41,76 cm3) e rendimento de tubérculos (5.288 kg ha-1) enquanto número máximo de tubérculos planta-1 (1,92) foi observado a uma profundidade de 10 cm. Tubérculos semeados em profundidade de 2,5 cm resultaram em produtividade mínima de tubérculos (4.538 kg ha-1) e altura de plantas (46,56 cm). Para maximizar a produção vegetativa e tubérculos de caládio cv. Flórida Sweet heart, será semeado no dia 30 de março com 7,5cm de profundidade.

ABSTRACT Ornamental bulbous crops emergence and yield can be improved by its emergence from soil. The response of Caladium to different planting depths and dates was investigated at Ornamental Horticulture Nursery, Department of Horticulture, The University of Agriculture, Peshawar during the year 2008. Randomized Complete Block Design in a split plot arrangement was used repeated three times. Sowing dates (30th March, 15th April and 30th April) were allotted to main plots whereas planting depths (2.5 cm, 5 cm, 7.5 cm and 10 cm) were kept in sub plots. Findings revealed that Caladium tubers sown on 30th March took maximum days to sprouting (33), produced maximum number of sprouts plant-1 (2.21), gained maximum tuber size (40.88 cm3) with high tuber yield (5397 kg ha-1). On the other hand, tubers sown on 30th April took less days to sprouting (20.21), produced less number of sprouts plant-1(1.53), produced small tuber (33.28 cm3) and total tuber yields was also less (4374 kg ha-1). In case of planting depth, Caladium tubers sown at a depth of 7.5cm resulted in maximum plant height (52 cm), tuber size (41.76 cm3), and tuber yield (5288 kg ha-1) while maximum number of tubers plant-1 (1.92) was observed at a depth of 10 cm. Tubers sown in 2.5 cm depth resulted in minimum tuber yield (4538 kg ha-1) and plant height (46.56 cm). To maximize vegetative as well as tubers production of Caladium cv. Florida sweet heart, it shall be sown on 30th March with 7.5cm depth.

Resveratrol (RSV) is a polyphenol produced by different plant species having a variety of biological activities. Synthesis of hybrid molecules of RSV with different natural and synthetic compounds has been studied. These hybrid molecules have been prepared by using fused or merged techniques or by using some linker groups. Wittig method was mostly applied by using the appropriate ylides to prepare the RSV core. The hybrid molecules prepared by these techniques exhibited anticancer, anti-inflammatory, antioxidant, anti-alzheimer, metal chelating and enzyme inhibitory activities. These hybrid RSV molecules can serve as a lead compounds for the future design of new drug molecules.