Iron-Chelating Property of Phytic Acid in Thalassaemia: An In vitro Study.

Aims: The aim of this study is to report an oral iron chelator phytic acid (PA), on blood samples from different types of thalassaemic patients of various age groups and physical conditions. Study Design: The In vitro iron chelating effect was evaluated by ferritin assay using ELISA. Methodology: Blood from the iron-overloaded 30 Thalassaemic patients of different age groups, body weights and heights were collected and the serum was separated. Patients without any history of blood transfusion and chelation therapy were taken as control group. The ELISA based ferritin assay was performed with standard phytic acid (40% water solution, Fluka), using Desferrioxamine (DFO) as control (0.5g Deferoxamine mesylate USP, Novartis, USA). The serum ferritin levels were recorded in two different conditions (treated with DFO and PA) at different time intervals (10, 30 and 60 min) by measuring absorbance at 450 nm. Results: The Kolmogorov-Smirnov test of patient samples in two different conditions showed that the ferritin concentration, treated by DFO and PA, was significantly decrease in PA treated group compared to DFO, when used in equivalent concentrations, at intervals of 10 min (P=0.760),30 min (P=0.537) and 60 min (P=0.055). Conclusion: The common iron chelators DFO or Deferiprone used as monotherapy may lead to transient and incomplete removal of iron, while PA showed a more complete and sustained removal of ferritin due to specific chemical binding at a wider pH range. However, further trial is required to establish its maintenance dose, comparative efficacy and mechanism of action.

Serum cortisol and prolactin response to surgical stress in infants and children.

In a prospective study on 40 infants and children undergoing elective surgery under general anaesthesia, serum cortisol and prolactin levels were compared to assess hormonal response to stress as regards to age, sex, length of surgery and anaesthetic techniques. The rise in serum cortisol was independent of age, sex, length of surgery and anaesthetic techniques while percentage rise in serum prolactin were more in females compared to males and significant post-induction surge irrespective of sex.

Immunohistopathological reactions for liver-specific membrane lipo-protein in experimental autoimmune hepatitis.

Antibody to the hepatocyte membrane protein, was induced in inbred strain C57BL/6 and C3H mice by immunisation with 100,000 g supernatant of syngeneic liver homogenate in CFA. Three weekly intraperitoneal injection of 200 ul of liver homogenate with CFA for continuous 4 weeks gave the best possible result. Histopathological changes were characterised mainly by perivascular inflammatory infiltrates and hepatocyte necrosis which mimicked human autoimmune hepatitis. In one of the immunological parameters, antibody to hepatocyte membrane protein (LSP) has been demonstrate by ouchterlony method in the test serum of those animals, who had received weekly doses of liver antigen. Thus in experimental autoimmune liver disease, semi-purified syngeneic liver fluid (S-100) leads to hepatic destruction and to an inflammatory process with several features in common with human chronic aggressive hepatitis. The presence of antibody against syngeneic liver antigen (S-100) in the test sera emphasizes that hepatocyte membrane protein does have an important role in liver tissue pathogenesis and disease process in experimental model. In this study we tried to prove that hepatocyte membrane protein may act as a target antigen in developing experimental autoimmune hepatitis.

Antiovarian antibody in premature ovarian failure.

Premature ovarian failure is a syndrome consisting of primary or secondary amenorrhoea, hypergonodotropiremia and hypoestrogenemia in women under the age of 40. An autoimmune mechanism was suggested as possible etiology when Vallolton and Forbes in 1966-67 found antibodies to the cytoplasm of rabbit ova in 29 of 232 tested sera. Immune mechanism in the pathogenesis of premature ovarian failure (POF) is suggested by association of autoimmune phenomenon with POF in some cases and demonstration of circulating antibodies to ovary in serum samples from women with POF. The incidence of presence of antiovarian antibody of POF patients has been reported earlier. Evidence of autoimmunity is present in 18-92% of patients with POF. In the present study we have studied 18 cases of POF without any overt manifestation of autoimmune disorder but the antiovarian antibody was detected, with the idea that this autoantibody might be the cause of ovarian dysfunction which is evident in POF. Presence of antiovarian antibody in 16.67% cases with POF in our study that ovarian antibodies may play a role in or reflect an autoimmune process responsible for the development of POF.

Cloning of ribosomal RNA genes from an Indian isolate of Giardia lamblia and the use of intergenic nontranscribing spacer regions in the differentiation of Giardia from other enteric pathogens.

The ribosomal RNA genes from an Indian isolate of Giardia lamblia have been cloned and characterized with respect to size, composition and copy number. Southern blotting and rDNA cloning of Giardia lamblia revealed that genes coding for ribosomal RNA (rRNA) are exceptionally small and are encoded within a 5.6 kb genome fragment repeat. The rDNA repeat unit of this isolate was found to be highly G-C rich like other human isolates and the physical map showed several SmaI sites. There are 132 copies of the rDNA repeat unit per cell in a head to tail arrangement. Two fragments corresponding to intergenic (0.2 kb and 0.3 kb) region and one (0.8 kb) containing both an intergenic region and a small part of the small subunit ribosomal RNA (SS rRNA) have been identified within the rDNA. These were used in heterogeneity studies of Giardia isolated from two geographic locations as well as in the analysis of cross reactivity with other enteric organisms. In Southern blots, all the three fragments were found to be highly specific for the differential diagnosis of Giardia spp. from the other enteric pathogens. These findings should help in developing a sensitive and more specific method for the diagnosis of giardiasis over currently available techniques.

Ocular injuries.

A total of 800 cases of ocular injuries were studied during the period from January, 1982 to December, 1985 at the department of eye, North Bengal Medical College and Hospital, Darjeeling. Major ocular injuries (n = 248) required hospitalisation. The rest 552 cases had minor injuries and treated at outpatients' department. The incidence of age, sex, mode of injury, interval between injury and first observation, structural damage were studied in all these cases.

Optimisation of cultural conditions for antifungal antibiotic accumulation by Streptomyces rochei G164.

To induce higher amount of antifungal antibiotic production by variation of cultural parameters has been studied. The maximum effectivity was found in sucrose as carbon source, peptone as nitrogen source and at pH 7.0. The effect of other selected factors were also evaluated in order to judge the variables that influenced antibiotic production.

Mutagenesis study to ameliorate the bacterial expression of phosphoprotein P of vesicular stomatitis virus.

The phosphoprotein gene of vesicular stomatitis virus, a Rhabdovirus, has been inserted into bacterial expression plasmids containing the Escherichia coli tac promoter and ribosome binding site (RBS). A low level of expression of the protein was detected. Sequence analysis showed the presence of 15 nucleotides in the spacer region i.e., between the Shine- Dalgarno sequence and ATG. Alteration of the distance and the sequence in the spacer region by oligonucleotide-directed mutagenesis revealed a correlation among the expression levels, accessibility of the RBS and requirement for a minimum spacing of at least 7 nucleotides between the Shine-Dalgarno sequence and ATG for optimal gene expression.

Curative effect of methionine on certain enzymes of chick kidney cortex under lanthanum toxicity situation.

Acute single dose administration of lanthanum chloride (250 mg/kg body wt, ip) to chicks have been found to alter the levels of enzymes of the antioxidant defence system of chick renal cortex fractions. Such changes involved significant decrease in activities of glucose-6-phosphate dehydrogenase, glutathione reductase, glutathione peroxidase and catalase of kidney epithelial cells. However glutathione-S-transferase activity was not altered. Glutathione and total thiol contents were decreased while lipoperoxidative reactions in kidney-cortex was significantly enhanced. The data indicate that amelioration of lanthanum toxicity condition by methionine supplementation may be due to the methionine serving as a precursor of glutathione.

Impact of chromium on lipoperoxidative processes and subsequent operation of the glutathione cycle in rat renal system.

Oral administration of K2Cr2O7 to male albino rats at an acute dose of 1500 mg/kg body wt/day for 3 days brought about sharp decrease in the activities of glucose-6-phosphate dehydrogenase and glutathione reductase of kidney epithelial cells. The scavenging system of kidney epithelium is also affected as evident by the highly significant fall in the activities of glutathione peroxidase, superoxide dismutase and catalase which ultimately leads to the increase in lipid peroxidation value in kidney cortical homogenate. However, glutathione-s-transferase activity in cytosol and glutathione and total thiol content in cortical homogenate were not altered. Chronic oral administration of K2Cr2O7 (300 mg/kg body wt/day) for 30 days to rats lead to elevation in the activities of glutathione peroxidase, glutathione reductase, glutathione-s-transferase, superoxide dismutase and catalase with no change in glucose-6-phosphate dehydrogenase activity in epithelial cells. This might lead to the increase in glutathione and total thiol status and decrease in lipid peroxidation value in whole homogenate system.

Antioxidant protection mechanism of chick hepatic mitochondria exposed to lanthanum chloride & neodymium chloride treatment.

Acute lanthanum chloride (250 mg/kg body wt) and neodymium chloride (200 mg/kg body wt) administrations resulted in significant enhancement of glutathione level in chick hepatic mitochondria. However, glutathione-s-transferase activity was depressed. There was no alteration in the activity of glutathione reductase. Activity of glucose-6-phosphate dehydrogenase was not altered under lanthanum and neodymium treatment. There was a significant enhancement of intramitochondrial glutathione peroxidase and superoxide dismutase. Lipid peroxidation remains the same as control group of animals.

Chicken erythrocyte membrane: lipid profile and enzymatic activity under lanthanum chloride and neodymium chloride administration.

Acute single dose (ip) administration of two rare earth elements like lanthanum chloride (250 mg/kg body wt) and neodymium chloride (200 mg/kg body wt) to chicks have been found to reduce the activity of certain erythrocyte membrane bound enzymes, viz. acetylcholinesterase, NADH dehydrogenase, Mg(2+)-ATPase, p-nitrophenyl phosphatase. Erythrocyte membrane bound glycosidases e.g. beta-D-glucosidase, beta-D-galactosidase and beta-D-glucuronidase were also reduced. Other components such as cholesterol and phospholipid residues were reduced but their ratio (cholesterol/phospholipid) remaining unchanged. Membrane sulfhydryl groups were also significantly inhibited by these rare earth elements.