Bangladesh Journal of Biochemsitry. Vol 4(1&2): 1998
INFLAMMATORY MEDIATORS IN CHILDREN AND ADULTS WITH SHIGELLOSIS

Pricila Khan MOLY, Laila N. ISLAM and Rubhana RAQIB
Immunology Laboratory, Laboratory Science Division, International Centre for Diarrheal Disease Research, Bangladesh. (ICDDR,B) and Department of Biochemistry, University of Dhaka, Dhaka-1000, Bangladesh.

Abstract
Inflammatory cells and the mediators secreted by the cells were studied at the cell level in the rectum of pediatric and adult patients with shigellosis to better understand their role, and in inflammation and in the immunopathogenesis of and recovery from the, disease. The histopathology of the gut after one month of onset showed that persistent inflammation was, seen more often in children (54%) than in adults (29%). Increased numbers of inflammatory cells including neutrophils and macrophages were present in the rectal mucosa in the acute stage of the disease and decreased during convalescence. Myloperoxidase (MPO) and lactoferrin (Lf) expressing neutrophils and inducible nitric oxide synthase (iNOS) expressing macrophages and neutrophils were significantly higher in the acute stage (3 to 5 days after onset of diarrhea) than in the convalescent stage (30 days after onset). The results suggested increased formation of reactive oxygen and nitrogen species by inflammatory cells during the acute, disease. Expression of superoxide dismutase (SOD), a scavenger of free radicals was also studied. Significantly lower numbers of superoxide dismutase (SOD) expressing cells were at local site during acute Shigella infection suggesting decreased scavenging of the reactive oxygen radicals that may contribute to tissue damage. Eosinophils gradually increased in numbers during convalescence. In line with this, expression of major basic protein (MBP), predominantly present in the granules of eosinophils also increased during convalescence. The study suggested that the mediators of the innate defense system were up-regulated in both adults and children during acute shigellosis. Persistence of inflammatory cells and the pro-inflammatory molecules released by these cells in the convalescent stage may contribute to the immunopathogenesis of severe colitis caused by Shigellae and  were suggestive of immune mediated inflammation in the rectal mucosa.   

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Bangladesh Journal of Biochemsitry. Vol 4(1&2): 1998
EFFECTS OF BACTERIAL ENDOTOXIN ON THE FUNCTIONS OF HUMAN LEUKOCYTES

Laila N. ISLAM, A. H. M. Nurun NABI, K. Mokim AHMED, Hasna Yusuf KANTA, Novera SULTAN and Kajla SEHELI.
Department of Biochemistry, University of Dhaka, Dhaka-1000, Bangladesh.

Abstract
Bacterial endotoxin is a potent agonist for priming and stimulating leukocytes. We investigated the effects of endotoxins of pathogenic bacteria: S. dysenteriae typhimurium and K pneumoniae on the functions of human neutrophils and lymphocytes. The endotoxins (lipopolysaccharides, LPS) induced morphological polarization of neutrophils in suspension and the responses were dose- and time- dependent. Variable proportions, 40-70%, of the neutrophils were polarized with different endotoxins as compared with N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) which stimulated about 90% of the neutrophils to become polarized. We found the endotoxins to be chemotactic stimuli for the neutrophils although not as effective as FMLP. The endotoxins bad and inhibitory effect upon the proportions of neutrophils phagocytosing opsonized yeast and the cell engulfed fewer yeasts.Interestingly, uniform concentrations of endotoxins stimulated the neutrophils to exhibit increased random locomotion (chemokinesis) through cellulose nitrate filters. Neutrophils pretreated with endotoxins showed an enhanced ability to reduce nitroblue tetrazolium (NBT) dye. The test endotoxins increased neutrophil adhesion to clean glass surfaces. Available data imply that very few lymphocytes direct from blood show polarized morphology but the cells acquire locomotor capacity during 24-48 hr culture with mitogens such as monoclonal anti-CD3 antibodies, phytohaemagglutinin (PHA), phorbol myristate acetate (PMA) or concanavalin A (Con A). We found that stimulation of human peripheral blood mononuclear cells (MNCS) with microgram levels of endotoxins in long–term culture resulted in an increase in the proportion of polarized cells which acquired locomotor morphologies. These cells were stained for acid a-naphthyl acetate esterase, and the majority of them were indentified as esterase negative B-lymphocytes which would release antibodies. These findings suggest that bacterial endotoxins modulate the functions of human blood neutrophils and lymphocyte.   

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Bangladesh Journal of Biochemistry. 4 (1&2): 97, 1998
THE EFFICACY OF PLANT HORMONES ON THE YIELD OF ASCORBIC ACID OF MANGO (MANGIFERA INDICA L) CV. KHIRSAPAT 

M. Ibrahim, MR Karim and MS Alam
Institute of Biological Sciences, Department of Biochemistry and Department of Botany, University of Rajshahi, Rajshahi-6205, Bangladesh. 

Abstract
The effects of foliar application of three different plant hormones at various concentrations on the mango cultivar of khirsapat were studied in order to control anthracnose disease, increase in yield and size and also to improve quality. Ten 8-year old trees of khirsapat cultivar were selected and grouped into A, B and C consisting of three trees in each group and one tree was marked as control. The trees of group A were sprayed separately with indol 3-acetic acid (IAA), 2,4-dichlorophenoxy acetic acid (2,4-D) and a-napthalene acetic acid (NAA) at a concentration of 10 ppm each. Similarly groups B and C trees were sprayed with these hormones at a concentrations of 20 and 30 ppm respectively. The trees were sprayed three times at an interval of 30 day. The first spray was carried out when the fruits attained pea size. The control tree was sprayed with water in identical condition. Only with 20 ppm NAA spray, significant development was observed in yield and size of the mango cultivar of khirsapat along with an increase of ascorbic acid content.   

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Bangladesh Journal of Biochemistry. 4 (1&2): 97, 1998
AGROBACTERIUM-MEDIATED TRASFORMATION OF BANGLADESH INDICA RICE FOR CONFERENCE SALT TOLERANCE

Zeba I. SERAJ, Haseena Khan, Noorain M. RASUL, M. Bakhtiar HOSSAIN, M. Rafiqul ISLAM, K. Mohammad ALI and Hasina AKHTER
Department of Biochemistry, University of Dhaka, Dhaka-1000. 

Abstract
Transformation protocols  with marker genes are being established with Bangladesh farmer-popular rice varieties as well as local and IRRI-derived salt tolerant varieties. Rice varieties do not produce osmoprotective compounds like mannitol and trehalose which have been shown to protect  against salt strees. It is our objective to transform moderately salt tolerant rice with osmolyte producing genes, so that there is a further enhancement of salt tolerance. In  collaboration with IRRI, we have acquired the genes  mannitol-1 phosphate dehydrogenase for production of mannitol and trehalose synthase and phosphatase for the production of trehalose. Transformation experiments have started with the mannitol-producing gene in BR 5331, and advanced T. Aman moderately salt tolerant rice variety. Other varieties being used are farmer-popular  BR-29 and IRRI salt tolerant variety IRS 1500. After proper mobilization of the plasmids containing genes for production of trehalose, into the correct Agrobacterium strain, we will start transformation using established protocols with marker genes and rice varieties which have been shown to be easily transformed.   

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:Bangladesh Journal of Biochemistry. 4 (1&2):99, 1998
SOME BIOCHEMICAL AND PHYSIOLOGICAL ASPECTS OF SUBMERGENCE TOLERANCE IN LOCAL BANGLADESHI RICE VARIANCE

M. Aftab UDDIN, Abdullahel AMIN, Sanjeeda AHAMED, M. Shahidul ISLAM, Monwar AZIZ, Moktadir Shahid HOSSAIN, Nityananda CHOWDHURY, Kuntal BISWAS, M. Anwar HOSSAIN
Department of Biochemistry, University of Dhaka, Dhaka-1000, Bangladesh
and A. Rashid GOMOSTA,
Department of Plant Physiology, Bangladesh Rice Research Institute (BRRI), Gazipur, Bangladesh. 

Abstract
Physiological screening for submergence tolerance of 156 varieties of rice (Oryza sativa L.), including both high-yielding and local varieties from different districts of Bangladesh  showed 8 tolerant (T) and 28 moderately tolerant (MT) varieties when tested at 15-day-old seedling stage. These results were confirmed by RAPD analysis with markers for susceptible and tolerant traits. The susceptible varieties (S) elongate much more rapidly under submergence and lodge when the water recedes. Biochemical studies, on 28 rice varieties which included 8 most tolerant, 11 moderately tolerant and nine most susceptible, showed that the two key enzymes of anaerobic glycolysis-pyruvate decarboxylase (PDC; EC 4.1.1.1) and alcohol dehydrogenase (ADH; EC 1.1.1.1), respectively, induced in almost all varieties exhibited higher levels of PDC and ADH activities than that of susceptible rice varieties.
Under submerged and covered conditions the carbohydrate depletion was significantly higher in susceptible rice plants than the tolerant and moderately tolerant ones. On the other hand , the rate of translocation of accumulated  carbohydrate from stem and leaf sheath to the panicle at maturity was minimum in the case of tolerant varieties. The α-amylse (EC 3.2.1.1) activity at seven days after flowering stage was higher in shaded condition than in natural light condition.