Anti-inflammatory activity of the latex of Calotropis procera

The anti-inflammatory property of the latex of Calotropis procera was studied on carrageenin- and formalin-induced rat paw oedema model. A single dose of the aqueous suspension of the dried latex was effective to a significant level against the acute inflammatory response.

Expression and characterization of a parasite-specific antigen on macrophages after infection with Leishmania donovani

A rabbit polyclonal antibody to crude soluble antigen of Leishmania donovani promastigotes recognized a determinant expressed on the surface membrane of mouse peritoneal macrophages and human monocyte derived macrophages infected in vitro. The determinant was recognized on infected macrophage surface only when F(ab')2 fragments of anti-leishmanial antiserum was employed in immunofluorescence. F(ab')2 fragments of human patient sera also could recognize the determinant. The expression of this antigen was not stage-specific for the parasite. Immunochemical analyses revealed this antigen to be of 51 kDa protein. Specific leaching of membrane proteins by trypsin showed three bands of expressed antigens of 26, 11 and 10 kDa, which in all likelihood might be arising from the 51 kDa antigen. The antigen was not expressed until 12 h of post infection, reached a maximum level at 24 h and thereafter attained a steady state level as studied upto 96 h of post infection. This type of antigen might have a great potential in immunodiagnostics and site-specific drug targeting.

Effect of lead exposure on plasma phenylbutazone levels in rats

The effect of lead exposure on phenylbutazone kinetics was studied in rats. The biological half-life (t1/2) of phenylbutazone was determined from the plasma level versus time curve in 3 groups of rats given (i) 10 mg/kg lead orally for 8 weeks (ii) 100 mg/kg single oral dose and (iii) no lead, after oral administration of 100 mg/kg phenylbutazone to all rats. The t1/2 of the drug was found to be 33% lower on chronic lead exposure and 46% higher on acute exposure than in unexposed control rats. This variation in the t1/2 values of the two different groups of rats indicates that probably phenylbutazone metabolism varies with the period of lead exposure.

Neurocysticercosis

Sixty-two cases of neurocysticercosis (NCC) were examined over a period of five years. Convulsive seizure was the commonest presentation (57%). The other modes of presentation included features of raised intracranial pressure (19%) meningoencephalitis (9%), "Stroke" like onset (4%) and progressive dementia (6%). Clinical signs were scanty. Six patients had papilloedema, five had hemiparesis while three had isolated cranial nerve palsies. Soft tissue calcification and mucocutaneous nodules were infrequent and was found in 13 (21%) and 5 cases (8%) respectively. Clinical suspicion supported by CT scan and Immunobiologic tests using ELISA were the mainstay in diagnosis. Praziquantel and Albendazole were found effective in the treatment of neurocysticercosis, but because of serious side effects encountered in some cases, the drugs should be used cautiously in selected cases only.

Potential of doxorubicin as an antileishmanial agent

Doxorubicin, a well characterized anticancer drug, was tested in vitro and in vivo for activity against Leishmania donovani. Activity in vitro was very high against both the promastigote and amastigote forms of this parasite with 50% effective dose (ED50) values on the order of 0.43 microM and 0.86 microM, respectively. An in vivo inhibition of spleen parasite burden up to 95% in an infected mouse model was achieved when a dosage of 625 micrograms doxorubicin/kg body weight/day was given in 4 consecutive doses, which is far less than the toxic dose. These results suggest that doxorubicin is highly active against visceral leishmaniasis and may be considered with second-line therapeutic agents such as amphotericin B and pentamidine.

Down-regulation of mannose receptors on macrophages after infection with Leishmania donovani

Macrophages express a mannose-specific endocytosis receptor that binds and internalizes mannose-terminated glycoproteins. Infection of mouse peritoneal macrophages with Leishmania donovani resulted in a decrease in mannose-receptor activity. With 125I-labelled beta-glucuronidase as ligand, a 2-fold decrease in uptake rate was observed in infected cells, with no change in Kuptake. Cell-surface binding of 125I-mannose-BSA was diminished 2.5-fold after infection. The decrease in ligand binding appeared to be due to a decrease in the number of sites, with no change in affinity. Elimination of parasites from infected cells by treatment with neoglycoprotein-conjugated methotrexate resulted in an increase in receptor number. Cycloheximide suppressed the drug-treatment-mediated rise in receptor number in infected macrophages. A decrease in receptor activity was also observed in liver Kupffer cells isolated from parasite-infected mice. Binding of ligand by another carbohydrate receptor, the mannose 6-phosphate receptor, was not altered by infection. Phagocytosis of yeast cells was also not altered. These results suggest that mannose receptor synthesis in macrophages is specifically suppressed after infection with Leishmania parasites.

Blood lead levels of children with pica and surma use

Blood lead levels of 253 Delhi children were estimated by dithizone method. In 82 (controls) children with no symptoms mean blood lead level was 9.6 micrograms/dl (+/- SD 6.8: median 10 micrograms); only 6 had high levels between 30-33 micrograms/dl. In 88 children with pica, the mean blood lead level was 23.0 micrograms/dl (+/- SD 13.82; median 17 micrograms) which was significantly higher than the control; 26 had high levels between 30-92 micrograms/dl. Sixteen children with pica and surma-use and 46 children suspected of lead poisoning showed lead level patterns like the pica group. However, 21 surma-using children without pica resembled the control group. Children with pica were significantly more anemic than the controls and showed higher prevalence of abdominal-neurological symptoms. Because, in India, blood lead cannot be estimated in most of the hospitals, it is suggested that children with severe pica, anemia, abdominal-neurological symptoms and exposure to surma or lead, be suspected of lead poisoning, kept in lead-free environment with corrected nutrition, and be given a short cautious therapeutic trial with oral penicillamine.

DDT levels in human body fat & milk samples from Delhi

A study of 45 human fat samples from autopsy and surgery specimens from Delhi showed a mean total DDT level of 6.37 micrograms/g (SE +/- 0.36; range 3.34-9.12 micrograms/g). While these values compare well with those reported from India and abroad, they are much lower than those obtained from other areas of Delhi, confirming wide variation in the quantity of DDT sprayed in different pockets of this city. Twenty one human milk samples from Delhi showed a mean total DDT level of 0.144 ppm (micrograms/ml). Thus, many infants in Delhi appear to be consuming 3 to 5 times the permissible 5 micrograms/kg/day quantity of DDT. This study too indicates the need of continuous monitoring of DDT and other insecticides commonly used in India.

Pharmacokinetics of intravenous metronidazole in neonates

Metronidazole is being extensively used in neonates for the prevention and treatment of anaerobic infections. However, detailed pharmacokinetic studies are not available. Thirty neonates receiving intravenous metronidazole 7.5 mg/kg at eight-hour intervals were studied with serial blood levels. The levels increased up to the third day of treatment and then reached a plateau. Neonates less than seven days of age showed higher levels than older infants. Septicemic neonates, however, showed continually rising levels. The half-life of metronidazole was 22.3 to 22.5 hours, approximately twice that in adults. This study indicates that neonates handle the drug differently than adults and may require it in lesser doses or at greater time intervals.

Some aspects of pharmacological profile of sodium curcuminate

Rapid i.v. injection of sodium curcuminate (NaC) produced transient hypotension and bradycardia in anaesthetized dogs and cats which were not blocked by bilateral vagotomy, atropine, mepyramine or propranolol. In open-chest anaesthetized cats, decrease in blood pressure and heart rate was accompanied by simultaneous transient reductions in left ventricular systolic pressure, maximal rate of rise of left ventricular pressure and a concomitant increase in left ventricular end-diastolic pressure. It was concluded that the transient hypotensive effect of NaC is due to its myocardial depressant action. NaC exhibited negative inotropic and chronotropic effect on isolated perfused rabbit heart, an antispasmodic effect on smooth muscle of dog s intestine in vivo and of vas deferens of guinea-pig in vitro but no effect on the rectus abdominis muscle of frog or its response to cholinergic stimulation.

Anti-inflammatory and irritant activities of curcumin analogues in rats

The anti-inflammatory activity of curcumin (C), sodium curcuminate (NaC), diacetyl curcumin (DAC), triethyl curcumin (TEC), tetrahydro curcumin (THC) and ferulic acid (FA) was compared with that of phenylbutazone (PB) using the carrageenin-induced rat paw edema and cotton pellet granuloma tests. The rank order of potencies of curcumin analogues and PB in carrageenin-induced inflammation were NaC greater than THC greater than C greater than PB greater than TEC. The curcumin analogues de decreased carrageenin-induced paw edema at low doses, however, at higher doses this effect was partially reversed. FA and DAC were devoid of anti-inflammatory activity. Curcumin analogues were less effective in inhibiting the granulomatous tissue formation. Maximum activity was observed with TEC whereas C, NaC and PB were almost half as effective as TEC. C and NaC possess both anti-inflammatory and irritant properties as was evident from experiments in which drugs were incorporated into carrageenin and the cotton pellets for inducing inflammation. The anti-inflammatory action of NaC is not mediated through release of steroids from the adrenal cortex or inhibition of the biosynthesis of prostaglandins from arachidonic acid. The results of the present study support the rationale for the use of powdered rhizome of tumeric (contains 0.6% of curcumin) for conditions of sprain and inflammation.

Copper metabolism in retinitis pigmentosa

Clinically and electrophysiologically confirmed cases of primary retinitis pigmentosa have been investigated regarding their copper metabolic state. It is observed that these patients show a normal or near normal serum copper concentration, very low plasma caeruloplasmin concentration, and a very high copper urinary excretion. A similarity between this condition and hepatolenticular degeneration is drawn and it is suggested that retinitis pigmentosa may also be a condition caused by an inborn error of copper metabolism.