Indian childhood cirrhosis: an inherited disorder of tryptophan metabolism?

Urine samples from members of 29 families of patients with Indian childhood cirrhosis (ICC) and nine families with related disorders gave positive reactions when tested with ferric chloride. Column chromatography showed that this was due to the presence of abnormally large amounts of tryptophan metabolites, notably 3-hydroxyanthranilic acid. Affected pedigrees had a significantly greater prevalence of peptic ulcer, adult cirrhosis, diabetes mellitus, migraine, and Parkinsonism than a control population. ICC may result from an inborn error of tryptophan metabolism in susceptible ethnic groups.     

Neisseria meningitidis: heterogenicity in the outer membrane proteins released into the growth medium

Eight strains of Neisseria meningitidis belonging to different serogroups were analysed for their virulence in mice and their release of outer membrane proteins into the medium during growth. All strains released proteins. No detectable lipopolysaccharide was observed. However, SDS-PAGE showed a heterogenicity in the protein number and profile among the different strains of N. meningitidis tested.     

New and Known Species of Pratylenchus Filipjev, 1936 (Nematoda: Pratylenchidae) from Haryana,India, with Remarks on Intraspecific Variations

Two new monosexual and one bisexual species Pratylenchus Filipjev, 1936 collected from Haryana state of India are described and illustrated. The primary distinguishing features of these species are Pratylenchus microstylus n. sp.: L = 331-458 μm, spear = 11 or 12 μm; Pratylenchus cruciferus n. sp.: L = 648-793 μm, central core of lateral fields with oblique lines, hemizonid 2-8 annules anterior to excretory pore; Pratylenchus ekrami n. sp.: spear = 11-13 μm, spermatheca oblong, post vulval uterine sac with differentiated cells, tail with 26-40 annules, males abundant. Studies on intraspecific variations of P. cruciferus, P. ekrami, and P. coffeae (Zimmermann, 1898) Goodey, 1951 revealed that spear length and value of ''V'' are the least variable characters. Body length and size of post vulval uterine sac varies to varying degrees in different species. Shape of median bulb in P. ekrami, number of incisures in P. coffeae, and tail shape in P. ekrami and P. coffeae exhibit the greatest amount of intraspecific variations. P. zeae Graham, 1936 and P. thornei Sher & Allen, 1953 are the other species collected during the present studies.     

Purification and properties of the alkaline phosphatase ofSerratia marcescens

1. A hypothesis based on the Hill-Bendall-model of photosynthetic electron transport is proposed to explain positive and negative photo-phobotaxis inPhormidium uncinatum. In the non-cyclic electron chain a pool is located into which photosystem II (e. g. by absorption by C-phycoerythrin, 561 nm) feeds electrons while photosystem I (e.g. 723 nm) drains electrons out of it.
2. Interruption of the electron flow into the pool causes a sudden decrease of the pool size and thus a positive phobic response. This happens e.g. when an organism leaves a trap which is illuminated by a wavelength absorbed by photosystem II pigments (e. g. 561 nm).
3. A negative reaction takes place when electrons are suddenly drained out of the pool; again the pool size decreases. This is the case when an organism enters a light trap illuminated by photosystem I light (723 nm).
4. The net flow of electrons into or out of the pool—and thus the reaction sense—can be manipulated by the relative excitation of the two photosystems or by blocking the electron influx by DCMU.

     

Cryopreservation of non-encapsulated embryogenic tissue of sweet potato (Ipomoea batatas)

Embryogenic tissue of the sweet potato (Ipomoea batatas (L) LAM) genotype TIB 10 was established from in vitro axillary shoot tips on Murashige and Skoog (1962) medium supplemented with 5 M 2,4-dichlorophenoxyacetic acid. Embryogenic aggregates of fresh mass 9.0–12 mg were subjected to a rapid freezing protocol in liquid nitrogen following sucrose preculture and varying degrees of dehydration. Up to 50% of embryogenic explants survived rapid freezing after preculture on 0.4 or 0.7M sucrose only. Dehydration with silica gel to moisture contents in the range 18–41% improved the survival after cryopreservation of embryogenic tissue. Tissue dehydrated for intermediate periods exhibited poor survival. Following freezing, embryogenic tissue appeared to develop normally, retaining its competence to produce mature embryos and plantlets.Abbreviations BA 6-benzyladenine - 2,4-D 2,4-dichlorophenoxyacetic acid - MS Murashige and Skoog (1962) medium     

Cross-Reactions of Human Lupus Autoantibodies with 8-Methoxypsoralen Photomodified DNA Fragments

DNA fragments of around 200 base pair (average size) have been covalently crosslinked with 8-methoxypsoralen under 365 nm UV light. The photoadduct, induced antibodies in rabbits with a titer of > 1:12,800 by direct bindng ELISA. Binding data showed that the induced antibodies are conformation-specific recognizing restricted conformational change at site of crosslinking. Human autoantibodies against DNA, bound not only to native DNA but to the photomodified DNA fragment as well. In addition, binding patterns of SLE sera obtained from different patients were remarkably similar, indicating the recognition of altered conformation of the modified polymer by naturally occurring SLE anti-DNA autoantibodies.     

Methanogenic granular sludge formation in an upflow anaerobic sludge blanket reactir treating synthetic methanolic waste

A laboratory upflow anaerobic sludge blanket reactor, seeded with fine, suspended, bacterial floc with 1.76 g volatile suspended solids/l, was used to treat synthetic methanolic waste. After 180 days of continuous peration, granular sludge with discrete granules of 1 to 2 mm diam. was formed, with 52 g volatile suspended solids/l. Granules were brown, relatively soft and had a settling velocity of 1.61 cm/s. Extracellular polymeric matter extracted from the granular sludge had high carbohydrate content but low nucleic acid content. The ash of the granular sludge contained Na⁺, K⁺ and Mg²⁺ up to 15.0, 11.7 and 3.75 mg/g, respectively. Scanning and transmission electron microscopy revealed that the granular sludge was dominated by methanogens resembling Methanosarcina.The authors are with the Department of Environmental Engineering, Faculty of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565, Japan     

The reproductive cycle in the population of Saccostrea cuccullatta (Born) from the coast of Karachi,Pakistan

Periphytic diatom communities on clay tile and sterilized rock substrates were compared with those on natural substrates. Clay tiles yielded diatom communities with the least variability between replicate samples, and the greatest similarity to the natural substrate assemblage. The advantages of utilizing introduced substrate communities and problems encountered with their simulation of the natural substrate community are discussed.