Study of azathioprine encapsulation into liposomes

The factors influencing the encapsulation of azathioprine (AZA) into liposomes were investigated to find out the conditions for its optimal entrapment. Similar studies for comparison were also carried out on 6-mercaptopurine (6-MP), of which AZA is a prodrug. AZA and also 6-MP show higher encapsulation efficiencies in MLVs as compared to LUVs. Variation in phospholipid composition does not seem to affect the loading capacity of either of the two drugs. The encapsulation efficiency of both the drugs improves upon addition of cholesterol in the bilayer, but the effect is seen only up to 30% cholesterol. Thereafter the effect becomes constant. AZA shows better incorporation in the positively charged liposomes as compared to those with neutral or negative charge. The entrapment of 6-MP is, however, found to be independent of the charge on the liposomes. Entrapment efficiency for both the drugs markedly depends on the pH of the hydration medium, yielding better entrapment efficiencies at high pH values. The rise in solute concentration initially causes increase in the entrapment of the two drugs which is followed by a decreasing phase.

Novel delivery systems for coagulation proteins

Long-term haemophilia prophylaxis with clotting factors administered by alternative delivery modes requires stable liquid formulations of these factors. We developed an aqueous-formulated human coagulation factor IX (hCFIX) with in vitro half-life (T 1/2) of 6 weeks at 37 degrees C and 18 months at 4 degrees C. Upon bolus subcutaneous (s.c.) injection in animals, hCFIX had a bioavailability of up to 16% compared to intravenous (i.v.) dose. When delivered by s.c. implanted pumps, hCFIX attained > 2% of normal human levels in the animal plasma. Hydrogels of hCFIX in a chitosan derivative, N,O-carboxymethyl chitosan (NOCC), released hCFIX slowly in vitro, and when injected s.c., gave prolonged plasma levels over those obtained by bolus i.v. or s.c. injection. Freeze-dried human coagulation factor VIII (hCFVIII) formulated in non-aqueous solvents had in vitro T 1/2 up to 80 days at 37 degrees C.

Possible mechanism of captopril induced endothelium-dependent relaxation in isolated rabbit aorta

The mechanism of captopril, an angiotensin converting enzyme (ACE) inhibitor with sulfhydryl group (SH) in its structure, to produce an endothelium-dependent vasorelaxation was studied. In rabbit aorta with intact endothelium and precontracted with phenylephrine, captopril and superoxide dismutase (SOD) produced dose-dependent relaxation. Lisinopril, an ACE inhibitor without a -SH group in its structure, did not produce endothelium-dependent relaxation. It was observed that captopril, like SOD, produced the relaxation by protecting the EDRF from getting inactivated by superoxide anions as pyrogallol and methylene blue inhibited both the captopril and SOD-mediated relaxation. The free radical scavenging action of captopril is further substantiated by the observation that captopril, but not lisinopril, inhibited FeCl3/ascorbic acid-induced lipid peroxidation in whole tissue homogenates of rabbit aorta to a level comparable to that of SOD. These results suggest that endothelium-dependent vasodilation produced by captopril may be due to its ability to scavenge superoxide anion and this property may be ascribed to the -SH group present in its structure.

Genomic polymorphism among Blastocystis hominis strains and development of subtype-specific diagnostic primers

Genomic polymorphisms among nine strains of Blastocystis hominis were examined by random amplified polymorphic DNA (RAPD) using four different arbitrary polymerase chain reaction (PCR) primers. Based on the RAPD patterns, nine strains were classified into three groups. The specific primers designed from the unique bands yielded a single band from within each same group, but did not amplify between all the groups examined. Specificity of these diagnostic primers was tested against several common intestinal parasites and a yeast, and no amplification was confirmed. Since the current criteria indicates that Blastocystis organisms isolated from humans are designated as B. hominis, the authors propose to classify several subtypes among B. hominis groups based on the difference of genomic DNA using three diagnostic primers.

Absence of Helicobacter pylori in oral mucosal lesions

A prospective study was conducted in 26 patients with benign oral ulcers and oral carcinoma and 26 age and sex matched controls to determine the prevalence of Helicobacter pylori in oral mucosal biopsies. Oral mucosal biopsies were subjected to rapid urease test, campylobacter like organism (CLO) test, histopathological examination and bacteriological culture for demonstration of H pylori. Urease test was positive for H pylori in 3 (11.4%) out of 26 cases and CLO test in 2 (14%) out of 14 cases. On histology, H pylori was identified in 4 (15.38%) out of 26 cases. The spiral organism was universally absent in culture of both patients and controls. These pilot data negate the casual association of H pylori in oral mucosal lesions.

Regain of fertility and normality of progeny born during below protective threshold antibody titers in women immunized with the HSD-hCG vaccine

PROBLEM

Phase II clinical trials with the heterospecies dimer of beta hCG and alpha-subunit of ovine luteinizing hormone (HSD)-human chorionic gonadotrophin (hCG) vaccine showed that pregnancy was prevented at and above 50 ng/ml titers, whereas conceptions occurred below 35 ng/ml of hCG bioneutralization capacity. The effect of below-protective threshold anti-hCG antibodies on the progression of pregnancy and the normality of progeny was studied.

METHOD OF STUDY

Four women enrolled by informed consent in the Phase II trials. The women studied were immunized with the HCG vaccine and did not receive booster injections in consideration of their desire to have another child. They were examined clinically at least once every month until delivery. The babies were followed up from 2 to 3.5 years, and their anthropometric indices were compared with elder siblings.

RESULTS

The pregnancies progressed to 35 to 38 weeks with the usual obstetric problems, and the children developed normally.

CONCLUSIONS

The anti-fertility effect of the HSD-hCG vaccine is reversible and low titers of antibodies below the protective threshold have no apparent side effects on the progression of pregnancy and on the early development of the progeny.

Cytopathic effect of Blastocystis hominis after intramuscular inoculation into laboratory mice

The present study investigated the pathogenesis of Blastocystis hominis by intramuscular injection of the organism into experimental mice. A total of 27 naïve BALB/c mice aged 6-8 weeks were injected in the leg muscle with axenic culture isolate B of B. hominis. Histological examination at different times revealed that B. hominis could produce a severe inflammatory reaction and myonecrosis. Most changes were observed at 6 h after injection and for up to 2-3 days. By 2 weeks the muscle had regained normal histology. There was infiltration of polymorphonuclear leukocytes (PML) into the injection site, indicating that B. hominis had a strong chemoattractant activity for PML.

Host vector system for high-level expression and purification of recombinant, enzymatically active alanine dehydrogenase of Mycobacterium tuberculosis

The 40-kDa antigen of M. tuberculosis, which is an alanine dehydrogenase, is a species-specific antigen that is potentially useful for strain identification. Large quantities of the purified protein are required for immunological, as well as for detailed biochemical and structural, characterization. The AlaDH gene was cloned by PCR from H37Rv (virulent) and H37Ra (partially attenuated) strains of M. tuberculosis, and their DNA sequence was determined. A host-vector system suitable for the production of sufficient quantities of the recombinant AlaDH antigen was developed. The AlaDH gene was expressed under the control of strong, transcriptional (bacteriophage pLpR) and translational (atpE) signals. High-level expression of soluble AlaDH was obtained using the recombinant E. coli K-12 strain CAG629 [pMSK12], which is deficient in Lon protease and the heat-shock response. A simple two-step procedure for the rapid purification of the recombinant protein was developed. The protein was purified to near homogeneity, and the purified AlaDH showed a specific enzyme activity comparable to the native protein isolated from M. tuberculosis. In addition, the product showed an expected amino acid sequence and reacted strongly to the 40-kDa (AlaDH)-specific mAb HBT-10. Furthermore, the epitope of the mAb HBT-10 was mapped to a 12-amino-acid region. Contrary to the published results, we show that the AlaDH and the PNT (pyridine nucleotide transhydrogenase) of M. tuberculosis do not share common epitopes reacting to the species-specific mAb HBT-10. The availability of highly purified AlaDH should now enable a detailed biochemical and structural characterization of this important enzyme of M. tuberculosis.

Oxidative transformations of 1-nitropyrene under simulated environmental conditions

The oxidation of 1-nitropyrene (1-NP), adsorbed on silica gel, with dimethyldioxirane (DMD) leads to the formation of 1-nitropyrene 4,5-oxide and 1-nitropyrene 9,10-oxide in a ratio of 74/26 (4,5-oxide/9,10-oxide). When the adsorbed 1-NP is exposed to the products of the gas-phase reaction of tetramethylethylene (TME) with ozone at -40 degrees C, the same oxides are produced in a ratio of 72/28. The fact that the ratio of the oxides is essentially the same in these two different types of experiments is highly significant. We have speculated that the gas-phase ozonolysis of TME produces an energy-rich form of the carbonyl oxide, acetone oxide. Some of this carbonyl oxide may cyclize to the isomeric DMD which, we propose, is responsible for oxide formation in the TME/ozone experiment. This proposal is supported by the observation that using ozone alone to oxidize 1-NP does not lead to oxide formation. Thus the oxidant responsible for oxide formation in the TME/ozone experiment must be produced in the ozonolysis. We suggest that this oxidant is DMD.

Cardiac mast cell stabilization and cardioprotective effect of ischemic preconditioning in isolated rat heart

This study was designed to investigate the effect of disodium cromoglycate (DSCG), a mast cell stabilizer, on cardioprotective effect of ischemic preconditioning. Isolated rat heart was subjected to 30 min of global ischemia followed by 30 min of reperfusion. Ischemic preconditioning was provided by four episodes of 5-min global ischemia followed by 5 min of reperfusion before sustained ischemia. Ischemic preconditioning and DSCG (10 and 100 microM) treatment markedly decreased the release of lactate dehydrogenase (LDH) and creatine kinase (CK) in coronary effluent and percentage incidence of ventricular premature beats (VPBs) and ventricular tachycardia/fibrillation (VT/VF) during reperfusion. Ischemic preconditioning and DSCG treatment also significantly reduced ischemia/reperfusion-induced mast cell peroxidase (MPO) release, a marker of mast cell degranulation. A significant increase in MPO release was observed immediately after ischemic preconditioning, and the release was found to be inhibited in hearts perfused with DSCG (10 and 100 microM) during ischemic preconditioning. DSCG administered during ischemic preconditioning (DSCG in ischemic preconditioning) attenuated the cardioprotective and antiarrhythmic effects of ischemic preconditioning. DSCG in ischemic preconditioning produced no marked effect on ischemia/reperfusion-induced MPO release. These findings tentatively suggest that DSCG administration during ischemic preconditioning abolishes its cardioprotective effect, perhaps by stabilizing resident cardiac mast cells.

Immunotherapy with Mycobacterium vaccae in the treatment of psoriasis

A placebo-controlled study of immunotherapy with Mycobacterium vaccae for chronic plaque psoriasis showed improvement in the psoriasis area severity index in 19 of 21 immunotherapy recipients (P<0.005). Minor improvement, not reaching statistical significance for the group, occurred in nine of 14 placebo recipients. There were losses to follow-up and the placebo used, tetanus toxoid, was not ideal. Clinical improvement after immunotherapy persisted for 6 months and another injection of the immunotherapeutic given to a few volunteers from either group resulted in benefits lasting a year. Lymphoproliferative tests were carried out at each clinic visit, and on 50 matched controls. Starting with reduced responses to mycobacterial antigens and concanavalin A, both treatment groups showed a fall after 3 months, and diverged at 6 months with M. vaccae recipients rising to values similar to those of healthy controls, whereas placebo recipients continued to fall. Conclusions reached were that immunotherapy with M. vaccae gave long-lasting clinical benefit to most patients, with minimal side effects. This accompanied a return towards normal cellular immune responsiveness to mycobacterial antigens, which did not follow the use of the placebo.

Characterization of a second calcium-dependent protein kinase from winged bean

In plants, Ca2+ has emerged as the predominant second messenger for signal transduction, as cyclic nucleotides are not known to play any significant role in this system. Earlier, we characterized an interesting Ca(2+)-dependent protein kinase, WbCDPK (winged bean calmodulin-like domain protein kinase), from the soluble fraction of winged bean (Psophocarpus tetragonolobus) shoot extract. Here an isoform of WbCDPK is purified to apparent homogeneity from the same winged bean shoot extract. It is a single polypeptide chain protein-serine kinase, having an M(r) of about 70,000 and like WbCDPK, its preferred substrates are histone H1, syntide 2 and MLC-peptide (a synthetic myosin light chain related peptide) and it is totally dependent on Ca2+ for its activity, but exogenous calmodulin (CaM) does not stimulate it. However, it is strongly inhibited by CaM antagonists, indicating the presence of a CaM-like domain, as in WbCDPK. The two enzymes do not cross react immunologically and the isoform differs significantly from WbCDPK in its apparent inability to catalyse the autophosphorylation reaction, which is known to cause down-regulation of substrate phosphorylation in the case of WbCDPK.

Transferrin directed delivery of adriamycin to human cells

Transferrin was covalently conjugated to adriamycin (Trf-adr) by the formation of a schiff base. This conjugate was found to bind to cell membrane trf receptors in a variety of human tumor cell lines. The Trf-adr conjugate was found to be active against sensitive and resistant cell lines e.g. Lovo, HL-60, H-meso and Hep2. It was, however, found that Trf-adr conjugate was more potent against resistant human tumor cell lines as compared to sensitive cell lines (based on cytotoxicity assays). The Trf-adr conjugate was then tested against nude mice bearing human mesothelioma tumors in their peritoneal cavity. The Trf-adr conjugate prolonged the lifespan of advanced tumor bearing nude mice as compared to either adriamycin alone or adriamycin and trf unlinked. Our studies show that trf can be successfully used as an ligand for directing anticancer drugs to human tumor cells.

Transurethral electrovaporization of the prostate--a possible alternative to transurethral resection: a one-year follow-up of a prospective randomized trial

OBJECTIVE

To compare the efficacy, safety and durability of transurethral electrovaporization of the prostate (TUVP) with standard transurethral resection (TURP) in a prospective randomized trial.

PATIENTS AND METHODS

The study included 104 consecutive men with symptomatic benign prostatic hyperplasia (BPH) admitted for surgery who were randomized to TUVP or TURP. The variables evaluated included the duration of surgery, catheterization and hospital stay, the International Prostate Symptom Score (IPSS), a quality-of-life assessment (QOL), the maximum urinary flow rate (Qmax) and the postvoid residual urine volume (PVR).

RESULTS

Both groups showed a comparable significant and maintained decline in the mean IPSS, from 26.5 to 4.4 (TUVP) and from 26.6 to 5.9 (TURP), and increase in mean Qmax, from 8.6 to 20.8 mL/s [corrected] (TUVP) and 8.6 to 22.8 mL/s (TURP) after 1 year. However, there were significant differences in the mean duration of catheterization (TUVP 20.9 h, TURP 46.6 h, P<0.001), hospital stay (TUVP 2.2 day, TURP 3.1 days, P<0.001), and the duration and volume of post-operative irrigation (TUVP none, TURP 18.1 h with 17.5 L of saline). Two patients in each group developed urethral strictures (4%) and two patients in each group required re-operation for residual adenoma (4%); two patients undergoing TURP had a bladder neck stricture (4%).

CONCLUSION

The results suggest that TUVP is as effective as standard TURP in the treatment of moderate-sized BPH. TUVP offers the advantage of using established instruments, has excellent peri-operative haemostasis and requires a shorter hospital stay.

Anaerobic septicaemia by Fusobacterium necrophorum: Lemierre's syndrome

Lemierre's syndrome is characterized by acute pharyngotonsillitis with secondary thrombophlebitis of the internal jugular vein which is complicated by multiple metastatic foci of infections. This syndrome is caused by Fusobacterium necrophorum in healthy young persons and is extremely rare in occurrence. A pre-school child with Lemierre's syndrome is reported. The diagnostic and therapeutic aspects are emphasized in order to sensitize physicians to this uncommon condition.

Renal cell carcinoma containing fat mimicking angiomyolipoma: demonstration with CT scan and histopathology

We report a case of a large renal tumour containing small amounts of fat and some calcification that proved to be a renal cell carcinoma. The CT appearance of the tumour was suggestive of an angiomyolipoma. Although the overwhelming majority of renal masses containing fat are angiomyolipomas, in the presence of calcification the diagnosis of renal cell carcinoma should be entertained.

Structural and kinetic properties of nonglycosylated recombinant Penicillium amagasakiense glucose oxidase expressed in Escherichia coli

The gene coding for Penicillium amagasakiense glucose oxidase (GOX; beta-D-glucose; oxygen 1-oxidoreductase [EC 1.1.3.4]) has been cloned by PCR amplification with genomic DNA as template with oligonucleotide probes derived from amino acid sequences of N- and C-terminal peptide fragments of the enzyme. Recombinant Escherichia coli expression plasmids have been constructed from the heat-induced pCYTEXP1 expression vector containing the mature GOX coding sequence. When transformed into E. coli TG2, the plasmid directed the synthesis of 0.25 mg of protein in insoluble inclusion bodies per ml of E. coli culture containing more than 60% inactive GOX. Enzyme activity was reconstituted by treatment with 8 M urea and 30 mM dithiothreitol and subsequent 100-fold dilution to a final protein concentration of 0.05 to 0.1 mg ml-1 in a buffer containing reduced glutathione-oxidized glutathione, flavin adenine dinucleotide, and glycerol. Reactivation followed first-order kinetics and was optimal at 10 degrees C. The reactivated recombinant GOX was purified to homogeneity by mild acidification and anion-exchange chromatography. Up to 12 mg of active GOX could be purified from a 1-liter E. coli culture. Circular dichroism demonstrated similar conformations for recombinant and native P. amagasakiense GOXs. The purified enzyme has a specific activity of 968 U mg-1 and exhibits kinetics of glucose oxidation similar to those of, but lower pH and thermal stabilities than, native GOX from P. amagasakiense. In contrast to the native enzyme, recombinant GOX is nonglycosylated and contains a single isoform of pI 4.5. This is the first reported expression of a fully active, nonglycosylated form of a eukaryotic, glycosylated GOX in E. coli.

The light gene of Drosophila melanogaster encodes a homologue of VPS41, a yeast gene involved in cellular-protein trafficking

Mutations in a number of genes affect eye colour in Drosophila melanogaster; some of these "eye-colour" genes have been shown to be involved in various aspects of cellular transport processes. In addition, combinations of viable mutant alleles of some of these genes, such as carnation (car) combined with either light (lt) or deep-orange (dor) mutants, show lethal interactions. Recently, dor was shown to be homologous to the yeast gene PEP3 (VPS18), which is known to be involved in intracellular trafficking. We have undertaken to extend our earlier work on the lt gene, in order to examine in more detail its expression pattern and to characterize its gene product via sequencing of a cloned cDNA. The gene appears to be expressed at relatively high levels in all stages and tissues examined, and shows strong homology to VPS41, a gene involved in cellular-protein trafficking in yeast and higher eukaryotes. Further genetic experiments also point to a role for lt in transport processes: we describe lethal interactions between viable alleles of lt and dor, as well as phenotypic interactions (reductions in eye pigment) between allels of lt and another eye-colour gene, garnet (g), whose gene product has close homology to a subunit of the human adaptor complex, AP-3.

Harm reduction and street-based program: looking into Nepal

In August 1991 the Lifesaving and Lifegiving Society (LALS) became the first nongovernmental organization in Nepal to work with injecting drug users (IDUs) to reduce the harm caused by drugs in order to prevent HIV/AIDS. Its mission is to provide education, counseling, and primary health care, as well as bleach, sterile water, condoms, and new needles and syringes to IDUs to lower their risk of acquiring blood-borne diseases. An evaluation of the program found that the prevalence of HIV infection among IDUs who were in regular contact with the program from 1991 to 1994 was 1.6%. No new cases of HIV infection were detected among participants in either 1993 or 1994. Though a harm reduction program is expensive to implement and sustain in Nepal, through its nonjudgmental, noncoercive, and confidential philosophy, LALS has engaged drug users into recovery and given them a platform by which they are able to address their concerns in a public forum.

Thelightgene ofDrosophila melanogasterencodes a homologue ofVPS41, a yeast gene involved in cellular-protein trafficking

Mutations in a number of genes affect eye colour in Drosophila melanogaster; some of these "eye-colour" genes have been shown to be involved in various aspects of cellular transport processes. In addition, combinations of viable mutant alleles of some of these genes, such as carnation (car) combined with eitherlight (lt) or deep-orange (dor) mutants, show lethal interactions. Recently, dor was shown to be homologous to the yeast gene PEP3 (VPS18), which is known to be involved in intracellular trafficking. We have undertaken to extend our earlier work on the lt gene, in order to examine in more detail its expression pattern and to characterize its gene product via sequencing of a cloned cDNA. The gene appears to be expressed at relatively high levels in all stages and tissues examined, and shows strong homology to VPS41, a gene involved in cellular-protein trafficking in yeast and higher eukaryotes. Further genetic experiments also point to a role for lt in transport processes: we describe lethal interactions between viable alleles of lt and dor, as well as phenotypic interactions (reductions in eye pigment) between alleles of lt and another eye-colour gene, garnet (g),whose gene product has close homology to a subunit of the human adaptor complex, AP-3.Key words: vesicle transport, eye-colour gene, heterochromatin.

Computational learning reveals coiled coil-like motifs in histidine kinase linker domains

The recent rapid growth of protein sequence databases is outpacing the capacity of researchers to biochemically and structurally characterize new proteins. Accordingly, new methods for recognition of motifs and homologies in protein primary sequences may be useful in determining how these proteins might function. We have applied such a method, an iterative learning algorithm, to analyze possible coiled coil domains in histidine kinase receptors. The potential coiled coils have not yet been structurally characterized in any histidine kinase, and they appear outside previously noted kinase homology regions. The learning algorithm uses a combination of established sequence patterns in known coiled coil proteins and histidine kinase sequence data to learn to recognize efficiently this coiled coil-like motif in the histidine kinases. The common appearance of the structural motif in a functionally important part of the receptors suggests hypotheses for kinase regulation and signal transduction.

Homologous plasma-stored tendon grafting in equids--gross and histomorphological observations

The efficacy of homologous plasma-stored tendon grafting in the superficial digital flexor tendon severed in the mid-metacarpal region was evaluated in 10 donkeys. Experimental tenectomies were performed, followed by grafting using plasma-stored tendon and human amniotic membrane encasement in group I (n=8) but no grafting or encasement in group II (control) (n=2). Gross observations in group I showed no peritendinous adhesions, except in one animal, while control animals showed thick fibrous adhesions and thickening at both the cut ends. Histologically, in the grafted tendon there was normal healing tissue at the junctional sites with negligible collagen fibre and mild regressing inflammatory reaction by day 15. By day 30 there were a great number of blood vessels but without any inflammatory reaction. The healing tissue at the grafted site and the adjoining paratenon was more mature. The fibroblastic activity appeared to be both extrinsic and intrinsic in origin. By day 60 fibroblastic activity was negligible and the healing tissue at the distal graft and host tendon junction site was at a more advanced stage of maturation and showed early fasciculi/bundle formation. Healing tissue at three months showed collagen fibres fasciculi/bundle comparable to normal tendon architecture. Tendon appeared histologically normal at four months after grafting.

Neonatal mechanical ventilation--experience at a level II care centre

One hundred and fifty nine neonates were ventilated over a period of one year of whom 74 (46.54%) survived. This study aims to analyse the indications, complications and outcome of babies requiring mechanical ventilation. The early outcome measures were (i) survival rate with respect to birth weight, gestation and indication of ventilation, and (ii) Complications of assisted ventilation. One hundred and forty seven babies received IPPV and 34 received CPAP. Twenty two out of these 34 required IPPV later. Survival was cent percent on exclusive CPAP mode. HMD was the commonest indication for ventilation followed by Birth asphyxia, Apnea of prematurity, Meconium Aspiration Syndrome and Persistent Pulmonary Hypertension of the New born. Survival rates increased with increasing birth weight and gestational age, changing from 25% for < 1000 gm and 20% for < 28 wks to 53% for > 2500 gms and 50.2% for > 37 wks. Prolonged ventilatory support was needed for HMD (mean 114 hrs) and PPHN (mean 156 hrs). Commonest complication was Sepsis (26%) followed by Pulmonary hemorrhage, Pneumothorax and IVH. Lower success rates in ventilation is due to the poor survival of babies weighing < 1000 gms and those with a gestation of < 28 wks with nosocomial infections as a major complication of assisted ventilation being an additional factor.

Preparation & standardization of the goat lung surfactant extract

Exogenous goat lung surfactant extract (GLSE) was obtained by chloroform-methanol extraction of the centrifuged lung lavage. Four lungs provided around 250 mg of surfactant. GLSE has a phospholipid content of 50 percent, cholesterol of 1.5 percent and protein content under 1 percent. The preparation was bacteriologically sterile and had a shelf life of at least one month at 4 degrees C. Endotracheal administration of surfactant (50 mg/kg) in a rat lung model rendered surfactant deficient by saline lavage, restored the compliance characteristics to normal, thus documenting biological activity of the preparation. The cost of a course of 2 doses of surfactant replacement therapy was estimated to be as low as Rs 500/-. The study opens up the possibility of surfactant replacement therapy for the management of neonatal respiratory distress syndrome in India by an indigenous product at an affordable cost.