Studies on the antidiarrhoeal activity of Aegle marmelos unripe fruit: Validating its traditional usage

<p>Abstract</p> <p>Background</p> <p><it>Aegle marmelos </it>(L.) Correa has been widely used in indigenous systems of Indian medicine due to its various medicinal properties. However, despite its traditional usage as an anti-diarrhoeal there is limited information regarding its mode of action in infectious forms of diarrhoea. Hence, we evaluated the hot aqueous extract (decoction) of dried unripe fruit pulp of <it>A. marmelos </it>for its antimicrobial activity and effect on various aspects of pathogenicity of infectious diarrhoea.</p> <p>Methods</p> <p>The decoction was assessed for its antibacterial, antigiardial and antirotaviral activities. The effect of the decoction on adherence of enteropathogenic <it>Escherichia coli </it>and invasion of enteroinvasive <it>E. coli </it>and <it>Shigella flexneri </it>to HEp-2 cells were assessed as a measure of its effect on colonization. The effect of the decoction on production of <it>E. coli </it>heat labile toxin (LT) and cholera toxin (CT) and their binding to ganglioside monosialic acid receptor (GM1) were assessed by GM1-enzyme linked immuno sorbent assay whereas its effect on production and action of <it>E. coli </it>heat stable toxin (ST) was assessed by suckling mouse assay.</p> <p>Results</p> <p>The decoction showed cidal activity against <it>Giardia </it>and rotavirus whereas viability of none of the six bacterial strains tested was affected. It significantly reduced bacterial adherence to and invasion of HEp-2 cells. The extract also affected production of CT and binding of both LT and CT to GM1. However, it had no effect on ST.</p> <p>Conclusion</p> <p>The decoction of the unripe fruit pulp of <it>A. marmelos</it>, despite having limited antimicrobial activity, affected the bacterial colonization to gut epithelium and production and action of certain enterotoxins. These observations suggest the varied possible modes of action of <it>A. marmelos </it>in infectious forms of diarrhoea thereby validating its mention in the ancient Indian texts and continued use by local communities for the treatment of diarrhoeal diseases.</p

Influence of the monsoon trough on air-sea interaction in the head of the bay of bengal during the southwest monsoon of 1990 (monsoon trough boundary layer experiment-90)

The analysis of 3-hourly time-series data on surface meteorological parameters collected at 20° N, 89° E in the head of the Bay of Bengal during the southwest monsoon period (18 August–19 September) of 1990 under the MONTBLEX-90 programme reveals considerable temporal variability in sea-level pressure, sea-surface temperature (SST) and the fluxes of heat and momentum at the air-sea interface. This variability is related closely to the north-south movement of the monsoon trough and the formation and development of synoptic weather systems during this period. A rapid increase in wind speed, cloudiness, instability, momentum flux, sensible heat flux and moisture flux (by 80 Wm-2), and a decrease of SST (by 0.3 °C) and net surface heat flux by 80 Wm-2, was associated with the development of a depression when the monsoon trough moved southwards. At the peak of the depression, values of the latent heat flux and evaporation reached up to 270 Wm-2 and 1.0 cm day-1 respectively. During the depression period the heat loss across the air-sea interface matched well with the heat loss in the upper (≈100 m) ocean. With the northward movement of the monsoon trough, the momentum and surface heat fluxes decreased rapidly while the sea surface gained heat energy at rates up to 195 Wm-

Coexistence of para and ferromagnetic phases of Fe3+ in undoped CdZnTe (Zn similar to 4%) crystals

The signatures of the coexistence of para and ferromagnetic phases for the Fe3+ charge state of iron have been identified in the low temperature electron spin resonance (ESR) spectra in undoped CdZnTe (Zn similar to 4%) crystals and independently verified by superconducting quantum interference device (SQUID) and AC susceptibility measurements. In the paramagnetic phase the inverse of AC susceptibility follows the Curie-Weiss law. In the ferromagnetic phase the thermal evolution of magnetization follows the well-known Bloch T-3/2 law. This is further supported by the appearance of hysteresis in the SQUID measurements at 2 K below T-c which is expected to lie in between 2 and 2.5 K. (C) 2010 Elsevier Ltd. All rights reserved

BOBMEX: The Bay of Bengal Monsoon Experiment

The first observational experiment under the Indian Climate Research Programme, called the Bay of Bengal Monsoon Experiment (BOBMEX), was carried out during July-August 1999. BOBMEX was aimed at measurements of important variables of the atmosphere, ocean, and their interface to gain deeper insight into some of the processes that govern the variability of organized convection over the bay. Simultaneous time series observations were carried out in the northern and southern Bay of Bengal from ships and moored buoys. About 80 scientists from 15 different institutions in India collaborated during BOBMEX to make observations in most-hostile conditions of the raging monsoon. In this paper, the objectives and the design of BOBMEX are described and some initial results presented. During the BOBMEX field phase there were several active spells of convection over the bay, separated by weak spells. Observation with high-resolution radiosondes, launched for the first time over the northern bay, showed that the magnitudes of the convective available potential energy (CA-PE) and the convective inhibition energy were comparable to those for the atmosphere over the west Pacific warm pool. CAPE decreased by 2-3 kJ kg(-1) following convection, and recovered in a time period of 1-2 days. The surface wind speed was generally higher than 8 m. s(-1). The thermohaline structure as well as its time evolution during the BOBMEX field phase were found to be different in the northern bay than in the southern bay. Over both the regions, the SST decreased during rain events and increased in cloud-free conditions. Over the season as a whole, the upper-layer salinity decreased for the north bay and increased for the south bay. The variation in SST during 1999 was found to be of smaller amplitude than in 1998. Further analysis of the surface fluxes and currents is expected to give insight into the nature of coupling

Ethnopharmacology, phytochemistry and pharmacology: a successful combination in the study of Croton cajucara

Phytochemical and pharmacological studies of Croton cajucara were oriented by traditional medicine. the stem bark of the mature plant is a rich source of clerodane-type diterpenes: trans-dehydrocrotonin (DCTN), trans-crotonin (CTN), cis-cajucarin B, cajucarin A, cajucarinolide and two novel clerodanes, trans-cajucarin B and sacacarin. in young (18-month-old) plants, the triterpene acetyl aleuritolic acid (AAA) was the major stem bark component and in these the diterpene DCTN was not present. the highest concentration of DCTN (1.4% of dry bark) was detected in 4-6 year-old plants, while 3-year-old plants contained only 0.26% of this diterpene. Three steroids (p-sitosterol, stigmasterol and sitosterol-3-O-beta-glucoside), two flavonoids (kaempferol 3,4',7-trimethyl ether and 3,7-dimethyl ether) and one diterpene (cajucarinolide) were isolated from the leaves of this Croton. the main pharmacological activity was correlated with DCTN. This clerodane produced anti-inflammatory and antinociceptive effects and a significant hypoglycemia in alloxan-induced diabetic rats. the compound also reduced the index of gastric lesions induced by restraint-in-cold. Dose-related DCTN and CTN inhibited in vivo the basal acid secretion in pylorus-ligature rats and oxyntic glands isolated from rabbit gastric mucosa, DCTN, CTN or AAA decreased in vitro uptake basal acid secretion induced by histamine and measured with the C-14-aminopyrine uptake method. Uniquely DCTN inhibited C-14-AP uptake induced by bethanechol. the terpenoids, DCTN and AAA, and the chloroform extract of 6-month-old plants reduced gastrointestinal transit in mice. the effects of DCTN and CTN on the survival of mice bearing Sarcoma 180 and Ehrlich carcinoma ascitic tumors, on the proliferation of cultured cells and TNF alpha were determined. DCTN was also evaluated for a possible antioestrogenic activity using the immature rat as a model system for bioassay of oestrogen and for an anti-implantation effect in regularly cycling rats. the biological experiments, using the plant extracts and the terpenoids DCTN, CTN and AAA, are herein discussed. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.Univ Fed Rio de Janeiro, Inst Quim, BR-21945970 Rio de Janeiro, BrazilUFPA, CCEN, Dept Quim, Belem, Para, BrazilUniv Fed Rural Rio de Janeiro, IB, Dept Ciencias Fisiol, Rio de Janeiro, BrazilUniversidade Federal de São Paulo, EPM, Dept Farmacol, Setor Prod Nat, São Paulo, BrazilUniv Fed Rural Rio de Janeiro, Dept Quim, Rio de Janeiro, BrazilUniv Estadual Londrina, CCB, Dept Biol Geral, Londrina, PR, BrazilUniv Fed Ceara, Dept Fisiol & Farmacol, Fortaleza, Ceara, BrazilUniversidade Federal de São Paulo, EPM, Dept Farmacol, Setor Prod Nat, São Paulo, BrazilWeb of Scienc