Separation of thoraco-omphalopagus Siamese twin.

A pair of female thoraco-omphalopagus twins, with two pairs of lungs, common diaphragm and separate pleural cavities was separated at the age of 5(1/2) months after a parasitic relationship had developed between them. Before separation both the babies developed recurrent respiratory tract infection and frequent diarrhea. They were treated with medical therapy and made fit for anesthesia. The combined weight of the twins was 4(1/2) kg at birth and the combined weight at the time of separation was 9(1/2) kg. One baby was smaller in growth compared to the other baby. The closure of anterior abdominal wall was difficult in both babies. However, we could close it without use of any biodegradable patches or tissue expander. Both the babies survived and are doing well after 3 months of separation.

Mercury detoxifying enzymes within endospores of a broad-spectrum mercury resistant Bacillus pasteurii strain DR2.

Bacillus pasteurii DR2, a broad-spectrum Hg-resistant bacterial strain, exhibited delayed sporulation and less mercury volatilization in the presence of mercury compounds. However, Hg-sensitive Bacillus subtilis sporulated quickly in the presence of HgCl2 and volatilized no mercury. Levels of Hg2+-reductase and organomercurial lyase in the endospores of Bacillus pasteurii DR2 were lower than those in vegetative cells.

Purification of two azoreductases from Escherichia coli K12.

Two azoreductases (I and II) were purified to homogeneity from extracts of E. coli K12. Azoreductase I was a dimer of two identical subunits of molecular weight 28000 whereas azoreductase II was a monomer of 12,000 molecular weight. Both NADH and NADPH functioned as electron donors for the azoreductases. Azoreductase I and II used Ponceau SX, Tartrazine, Amaranth and Orange II as substrates. Ponceau SX was the best substrate for both the enzymes. However, azoreductase II utilized tartrazine, amaranth and orange II less efficiently than azoreductase I.

Identification of immune complex antigens in sera of Indian kala-azar patients.

Level of circulating immune complex (IC) in visceral leishmaniasis is much higher than that in control sera. In immunoblot experiment, treatment of kala-azar IC with patient sera showed at least 6 bands of which the band around 55 kDa region was most prominent. The band at 55 kDa is primarily due to the presence of an antigen recognized by its corresponding antibody present in the patient sera. This was confirmed by using radiolabelled antibody from kala-azar patient serum and antipromastigote serum. The heavy chain of IgG originating from IC is also present in the same region which was detected by its recognition with antihuman IgG. The IC gave a band at 55 kDa region with sea-urchin antitubulin. Kala-azar sera also reacted with purified rat brain tubulin. The present results suggest that a tubulin like protein is present at 55 kDa region along with the heavy chain of IgG.

Plasma membrane of Leishmania donovani.

Plasma membrane of Leishmania donovani promastigotes was isolated by disrupting the cells in Dounce homogenizer and found to be having two fractions M1 and M2. Chemical analysis of the two membrane fractions revealed that M1 had less RNA content and high sterol-phospholipid molar ratio than M2. M1 was also rich in membrane marker enzymes, e.g., 5' nucleotidase and acid phosphatase. Glucose-6-phosphatase, the marker enzyme of endoplasmic reticulum was higher in M2 fraction. The electron micrograph also revealed the presence of plasma membrane vesicles in M1 fraction.

Effect of ureastibamine on Leishmania donovani amastigote.

Ureastibamine, a pentavalent antimonial, reduced the parasitic load in the 60-day model of infection of L. donovani in hamsters. It also inhibited the in vivo multiplication of I donovani amastigotes in hamster peritoneal macrophages. No inhibition in either promastigote multiplication or amastigotes transformation was noted with filtrate obtained after incubation of the drugs for 72 h in the macrophage culture. Incubation of macrophages with ureastibamine revealed an impairment in the uptake of deoxyglucose. The effect of ureastibamine was compared with that of another pentavalent antimonial, sodium stibogluconate. It is suggested that impairment of macrophage membrane may contribute towards the adverse effect of these drugs against the intracellular parasite.

Characterization of potentially pathogenic free-living amoebae in sewage samples of Calcutta, India

1. It is widely accepted that foul or polluted environments are the principal sources of potentially pathogenic species of free-living amoebae. The present paper is the first report of occurrence of potentially pathogenic free-living amoebae in sewage sample of Calcutta, India. 2. We describe the occurrence, isolation, specific identification and comaprative mouse pathogenicity test of two pathogenic amoebae, viz., Naegleria fowleri (N. aerobia) carter, 1970, causing human meningoencephalitis and Acanthamoeba castellanii Douglas, 1930, causing granulomatous amoebic encephalitis, and one non-pathogenic amoeba, viz., A astronyxis Ray and Hayes, 1959, in sewage samples of Calcuta, India. 3. The existence of both pathogenic and non-pathogenic amoebae living side by side is of considerable epidemiological relevance

Excreted factors and membrane-associated carbohydrates of Indian leishmaniae.

Antigenic identity between the cell surface carbohydrate ligands and their excreted factor (EF) in all forms of Indian leishmaniasis were assessed by 11 carbohydrate-specific lectins. Our results demonstrated that 3 lectins, viz. PNA, SBA and WFA showed unique selectivity towards skin-dwelling parasites. The EFs of visceral leishmaniasis (VL), post-kala-azar dermal leishmaniasis (PKDL) and cutaneous leishmaniasis (CL) formed band against ConA at 1000, and 500 micrograms/ml concentration, respectively. RCA-120 at 3 mg/ml concentration was positive to both Leishmania tropica and L. major, whereas SBA was specific to L. tropica, L. major and PKDL strains at the same concentration. Antisera directed against the EFs (EF-As) induced agglutination to homologous promastigotes suspension. Cross-reactivity of agglutination was observed in different strains but highest was found among PKDL and CL strains. Although PKDL cases are normally found in patients with the history of visceral leishmaniasis (kala-azar), surprisingly in this study, the surface saccharides of PKDL strains had close affinity to CL type instead of VL.