New synthetic precocenoids as potential insect control agents.

Ageratochromes or precocenes are known for their insect growth regulating (IGR) activity. The present investigation was taken up with an objective to look for the lead structure in these compounds which can be elaborated synthetically to obtain useful growth regulators for practical purposes. With this in mind, some variants of precocenes were synthesized in the laboratory and tested for their toxicity and growth regulating activity using red cotton bug Dysdercus koenigii as the test insect. Most of the precocenoids showed toxicity of various degree and metamorphic derangements to different extents. Adults emerging from treated nymphs could not complete the normal life span. Among the compounds tested 8-acetyl-7-hydroxy-5-methoxy-dimethylchromene (alloevodinol) was more toxic and also showed developmental defects at very low dose such as 0.5 mg l(-1)/nymph. Precocene II (6, 7-dimethoxy-2, 2-dimethylchromene) was used as the standard compound. It was the least toxic and showed effects at 30 mg l(-1)/nymph.

Acute myocardial infarction secondary to myocardial bridge treated with drug-eluting stent.

We report a case of myocardial bridge in left anterior descending coronary artery associated with acute anterior wall myocardial infarction. The patient had many unusual features like coronary ectasia and atherosclerosis within the myocardial bridge segment. The patient was treated with drug-eluting stent under intravascular ultrasound guidance with good result over 6 months follow-up.

Congenital atresia of left main coronary artery.

We report a rare case of congenital atresia of left main coronary artery in an elderly male presenting with angina and positive stress thallium test. Coronary angiogram showed absence of left main coronary artery in the left aortic sinus. Collaterals from right coronary artery supplied left anterior descending artery and left circumflex artery territories. Despite collaterals, the left anterior descending and left circumflex arteries were rudimentary. Poor size of left-sided arteries precluded any surgical revascularization which is the treatment of choice in this rare entity.

A comparative study of allitin and garlic on lipid turnover in a teleost, Anabas testudineus (Bloch).

Both allitin and garlic have anti-lipogenic properties substantiated by the activity of three lipogenic enzymes and lipid profiles. The rise in the HDL levels and simultaneous fall in the LDL upon garlic intake is the most convincing indicator of reduced lipid concentration. However, the administration of allitin recorded a decrease in the HDL and LDL levels, but when calculated on a percentage basis, there was a marginal increase in the HDL level. On the basis of results, it can be concluded that garlic or its derivatives have hypolipidaemic effect in submammalian vertebrates also. The cholesterol lowering effect of allitin and garlic can be commercially exploited for producing fish with low cholesterol for possible human consumption.

99mTc-labeled field bean protease inhibitor can function as an efficient tumor detecting agent.

Purified field bean protease inhibitor (FBPI) was labeled with 99mTcO4- to ascertain its ability to locate tumors in tumor-bearing rat models. The labeling was done with Sn2+ as a reducing agent and the yield was 95%. It was stable for 2 hr at ambient temperature. The biodistribution study of the intravenously injected radiolabeled FBPI in normal Wistar rats at various time intervals showed a rapid blood clearance from the systemic circulation (approximately 5hr). The complex was predominantly excreted through the renal and the hepatobiliary systems. In vivo distribution and scintiimaging of 99mTc-FBPI were carried out in rats bearing carcinogen-induced mammary tumor or transplanted C6-gliomas. The results obtained were compared with conventional tumor-seeking radiopharmaceuticals such as 99mTc-(V)dimercaptosuccinic acid (DMSA), 201Thallous chloride (TICI) and 99mTc-Citrate. The tumor to muscle (T/M) ratios obtained with 99mTc-FBPI in rat C6 glioma was nearly 2 to 5-fold higher than obtained with all the three conventional tumor-seeking agents. The T/M ratio obtained with 99mTc-FBPI in rat mammary tumor on the other hand appeared to be 2-3-fold higher than noted with 99mTc(V)-DMSA and 201TlCl. The ratio was however comparable with that obtained with 99mTc-Citrate. The study indicated that 99mTc-FBPI has the specific potentials for imaging gliomas and possibly other tumors as well.

Alterations in brain tumor DNA detected by a fingerprinting probe.

We used a novel DNA fingerprinting probe O-chi-1 (ref. 1) to detect differences in the hybridization pattern of brain tumor DNA and paired normal tissue of a given individual. Representatives of meningiomas (two), glioblastoma multeforme (three) and astrocytoma (one) were studied. Alterations, which included amplification as well as the loss of a normal band in tumor DNA, were observed in four of the six tumours. While the increased intensity of a band can be taken to imply increased copy number, the disappearance of bands could either be due to loss of DNA sequence or rearrangement resulting in different sized bands.

Fate of leucine in the biosynthesis of bakuchiol, a meroterpene from Psoralea corylifolia.

Significant incorporations of labelled leucine, valine and isovaleric acid into the meroterpene, bakuchiol (1) isolated from the medicinal plant, Psoralea corylifolia have been observed. Degradation experiments show that labels from these substrates find their way into both phenylpropane derived as well as terpenic part of 1 thereby indicating that none of the known pathways is operative in the case of 1. It is suggested that these substrates are metabolised to CO2 which is then incorporated into 1.