Scarlet gourdCoccinia grandis little-known tropical drug plant

Coccinia grandis (Cucurbitaceae), scarlet gourd, is widely distributed throughout the tropics and can be found in both wild and cultivated states on the plains of India. Although the sweet type is extensively cultivated for its edible fruits,C. grandis may have some potential value as a remedy for diabetes. A brief account of the botanical aspects and the food and the potential medicinal value of the different promising cultivars is provided.     

Effects of medium alterations on in vitro development of Brugia malayi larvae in cultured mosquito thoraces.

A recent study showed that 1-day-old, intracellularly lodged larvae of Brugia species develop in vitro to the infective third-stage larvae (L3) in excised thoraces of susceptible mosquitoes in the diphasic insect tissue culture medium containing a nutrient agar base overlaid with a 1:1 mixture of Schneider's Drosophila medium and Grace's insect cell culture medium supplemented with 20% fetal bovine serum (FBS) and antimicrobial agents. In the present investigation, the diphasic culture medium was used to evaluate the effects of medium alterations on the development of 1-day-old, intracellularly lodged larvae of subperiodic Brugia malayi in excised thoraces of Aedes aegypti to the L3. One-day-old larvae developed to the L3 in medium without nutrient agar base, at pH 7.0 and pH 7.5, in Hanks' balanced salt solution (HBSS) and in HBSS supplemented with bovine albumin fraction-V (BAF-V). These larvae also developed in the absence of FBS in the overlay medium, in overlay medium containing 5-20% FBS, in medium components obtained from different sources, in serum free Sf-900 (GIBCO) medium, and when FBS is replaced by BAF-V in the overlay medium. The percentage of L3 was not increased substantially in infected excised thoraces of mosquitoes when nutrient supplements, such as folic acid, p-aminobenzoic acid, glucose, lipid concentrate, hemin, or reduced glutathione, were added to the overlay medium containing BAF-V. These results suggested that 1-day-old, intracellularly lodged larvae developed to the L3 in infected excised thoraces of mosquitoes at almost the same rate as in intact mosquito, when excised thoraces were maintained alive under optimal conditions in a culture medium.     

The impact of petroleum hydrocarbons (diesel) on periphyton in an impacted tropical estuary based on in situ microcosms

The distribution of petroleum hydrocarbons and their effects on the periphytic algal biomass using in situ microcosms were investigated in Ponggol estuary located on the northeastern coast of Singapore. Dissolved or dispersed petroleum hydrocarbon (DDPH) concentrations in the surface and bottom waters and absorbed or adsorbed petroleum hydrocarbon (AAPH) concentrations in sediments were monitored from July 1999 to June 2000. Results showed concentrations ranging from 4.42 to 248.94 μg l⁻¹, from 0.35 to 1099.65 μg l⁻¹, and from 20.55 to 541.01 mg kg⁻¹ for DDPH in surface and bottom waters and AAPH in sediments, respectively. Accidental spillages of fuel from dredgers operating in the estuary, fuel and engine oil from recreational boats, shipping operations in the adjacent strait, and runoff monsoon drains in the vicinity were some of the possible sources of petroleum hydrocarbons in the estuary. An assessment of environmentally realistic concentrations of petroleum hydrocarbons on periphytic algal biomass using in situ microcosms revealed signs of acute toxicity. A reduction in periphytic algal biomass (with respect to controls) of 68-93% was observed for various treatments exposed to diesel.     

Mosquito transmission of wild turkey malaria, Plasmodium hermani.

Culex nigripalpus experimentally transmitted Plasmodium hermani, a plasmodium of wild turkeys (Meleagris gallopavo) in Florida. The mosquitoes were infected by feeding upon blood induced parasitemias in domestic turkey poults. The resulting sporozoites, transmitted by either mosquito bites or injection, produced malaria infections in domestic poults.     

Chemoreceptor sensitivity and maladaptation to high altitude in man

Studies were carried out to find out the role of chemoreceptor sensitivity in the causation of maladaptation syndromes on acute exposure to altitude. The experiments were done in two phases. In phase I, the responses in chemoreceptor sensitivity were studied in altitude acclimatized subjects and compared with those who suffered from either High Altitude Pulmonary Oedema (HAPO) or Acute Mountain Sickness (AMS). In Phase II, a similar comparison was done in two groups of subjects, one representing normal sojourners at 3,500 m and the other being subjects who had just recovered from HAPO. The first phase was done at Delhi; and the second at an altitude of 3,500 m. Parameters of assessment were hypoxic sensitivity, carbon dioxide sensitivity, ventilation (VE), respiratory frequency (Rf), forced vital capacity (FVC), forced expiratory volume at the first second (FEV1), heart rate (HR), blood pressure (BP), and oral temperature (Tor). The results showed significantly lower sensitivity to both hypoxia and carbon dioxide in maladapted subjects, as compared to those who were acclimatized in both the categories suggesting thereby that reduced chemoreceptor sensitivity might be an initiating factor in the causation of maladaptation syndromes at altitude.     

Uses of Plants and Plant Products in Traditional Indian Mural Paintings

The genius of Indian paintings was first manifested in the Ajantan mural art which spanned a whole millennium from the second century B.C. to the eighth century A.D. This rich tradition, which continued up to the nineteenth century under the patronage of different dynasties in India, declined by the end of that century. But this cultural heritage has been kept alive by a few artists in Kerala who practice even today the methods and techniques of mural paintings similar to those practiced by the Ajantan mural painters. Plant materials and/or plant products used during different phases of a mural painting, from preparation of the base wall to the finishing touches of the creation are identified and pro-cessing and application detailed. Ajantan and post-Ajantan murals are reviewed and the ma-terials, methods and techniques used in them are discussed.     

Variation in the susceptibility to cold injury in Indians

The peripheral vascular responses during local cold stress, (heat output from the hands and cold induced vasodilatation-CIVD response) were studied on 4 groups (10 each) of Indian population, viz., South-Indians, North-Indians, Gurkhas and High Altitude Natives (HAN) of 3,500m. The parameters were recorded at Delhi, and at 3,500 m in thermoneutral laboratory (25–28°C). The sea level readings of HAN were taken after 3 weeks of their stay at Delhi; and that of lowlanders at 3,500 m were taken after 3 weeks of their sojourn. The results show that the heat output and CIVD were highest in HAN, and lowest in the South-Indians. The responses of the other two groups were similar in nature and were better than that of South-Indians. Based on an earlier study which has shown that individuals with higher heat output and CIVD are better protected against the occurrence of cold injuries, it can be suggested that HAN are most resistant and the South-Indians are highly susceptible to the occurrence of cold injuries.