Purine salvage as metabolite and energy saving mechanism in Camelus dromedarius: the recovery of guanine

The preservation of purine ring as purine bases appears to be a common feature of camel liver. Hepatic guanine appears to be actively converted into GMP in the camel rather than further degraded. The limiting step of guanine degradation appears to be the lack of hepatic guanase activity. Higher purine bases over uric acid ratios were found in camel urine with respect to those of zebu.     

Isolation and characterisation of nuv11, a mutation affecting meiotic and mitotic recombination in Aspergillus nidulans

A mutant of Aspergillus nidulans, designated nuv11, has been isolated as hypersensitive to the monofunctional alkylating agent MNNG and the quasi-UV-mimetic mutagen 4-NQO. The mutation was recessive, resulting from mutation of a single gene which mapped to chromosome IV, and was non-allelic to the previously characterised repair-deficient mutations uvsB and uvsH which are also located on this linkage group. The nuv11 mutation results in slow growth, deficient intragenic and intergenic meiotic recombination, increased spontaneous chromosome instability, and increased intragenic and intergenic mitotic recombination in homozygous diploids. By screening a wild-type gene bank of A nidulans, a clone (pNUV11A40) has been isolated which complements the nuv11 mutation, restoring wild-type responses to both MNNG and 4-NQO.     

Glycoalkaloids of Solanum Series Megistacrolobum and related potato cultigens

Glycoalkaloids were used as evidence of the affinities of nine taxa of Solanum Series Megistacrolobum and related potato cultigens from western Bolivia. S. boliviense, S. sanctae-rosae and S. toralapanum contain the commertetraose sugar moiety and appear to represent a relatively wild group within the Series. S. megistacrolobum, S. sogarandinum and S. raphanifolium show anomolous glycoalkaloid profiles that probably reflect hybridization associated with human disturbance. Primitive forms of the S. χ ajanhuiri cultigen are indistinguishable chemicaliy from conspecific weeds that were previously classified as S. megistacrolobum. Variation in total glycoalkaloid content within Series Megistacrolobum likely reflects direct selection by humans for reduced glycoalkaloid levels during the domestication process.     

On the morphology,behaviour and systematic status of the assam macaque (Macaca assamensis McClelland, 1839)

Studies on a living and freshly dead male ofM. assamensis at Y.R.P.R.C. supplemented by notes on a living pair and their male offspring observed at the Z.S.L., enable us to supplement existing data on the somatology, craniology, dental anatomy and behavioural features of the species. Collectively the new data necessitate taxonomic revision of the status of the species, viz: its removal from immediate association withM. mulatta (subgenusMaimon) and alignment within the subgenusZati. Zoogeographical discontinuity in this subgenus is compared with that of the subgenusSilenus.     

Meiobenthic distribution and nematode community structure in five European estuaries

Meiofauna from the intertidal zone of five European estuaries (Ems, Westerschelde, Somme, Gironde, Tagus) was investigated. Samples represented a cross section of various benthic habitats from near-freshwater to marine, from pure silts to fine-sandy bottoms. The meiobenthic community comprised everywhere a fauna strongly dominated by nematodes, with meiobenthic density increasing with increasing salinity. The Ems differed from the other estuaries due to the presence of a well developed community of Copepods, Gastrotrichs, large Ciliates and/or soft-shelled Foraminiferans in some sites. The Westerschelde stood out due to the near-absence of harpacticoid copepods and, as in the Tagus, the lower meiobenthic densities in the marine part of the estuary. For nematode community analysis, we also included data from the Tamar which were obtained from the literature (Warwick &; Gee, 1984). This resulted in the enumeration of 220 species, belonging to 102 genera, each with a characteristic distribution along the salinity, sedimentary and latitudinal gradients. Using the multivariate technique CANOCO, a zonation along these different physicochemical determinants was observed as well although salinity and sediment characteristic (scale of hundreds of meters to kilometers) proved to be more important in explaining community structure than latitudinal differences (scale of hundreds of kilometers). Nematode diversity was nearly entirely determined on the genus level and was positively related to salinity. Deviations from this general trend in the Gironde and the Tamar were attributed to sedimentary characteristics or to low macrobenthic predation. The presence of a typical opportunistic colonizing nematode species Pareurodiplogaster pararmatus in the low-salinity region of the Gironde could indicate (organic?) pollution or disturbance of the intertidal mud-flats.     

Simultaneous Determination of Fluzinamide and three of its active metabolites in plasma by high-performance liquid chromatography

A sensitive and selective high-performance liquid chromatographic method has been developed for a new anticonvulsant, fluzinamide, and three of its active metabolites. This method requires only 0.5 ml of plasma, and it involves a single extraction with a mixture of hexane—dichloromethane—butanol (55:40:5). The plasma extract is chromatographed on a 10-μm, C₁₈ reversed-phase column and quantitated by ultraviolet absorbance at 220 nm. The concentration—response curve for all four compounds are linear from 0.05 μg/ml to at least 10 μg/ml. The extraction efficiency of this method is greater than 90%. The accuracy and precision of the method were tested by analyzing spiked unknown samples that had been randomly distributed across the concentration range. The mean concentrations found were within ± 9% of the various amounts added with a standard deviation of ± 3.5%. This method has been successfully applied to the analysis of samples obtained from fluzinamide-dosed dogs, healthy unmedicated volunteers, and patients who were at steady state with phenytoin, carbamazepine, and fluzinamide.     

Nucleotide sequences of the trpG regions of Escherichia coli,Shigella dysenteriae,Salmonella typhimurium and Serratia marcescens

The nucleotide sequences of Serratia marcescens trpG and the corresponding regions of Escherichia coli, Shigella dysenteriae and Salmonella typhimurium trpD have been determined. Analysis of the nucleotide sequence divergence suggests the following evolutionary relationships: Serratia-[Salmonella, (Escherichia, Shigella)]. Partial reconstruction of ancestral nucleotide sequences and subsequent analysis of nucleotide substitutions show that the majority of nucleotide substitutions in the evolution of trp(G)D are transitions that result in a reduction of G + C content. Since most of the nucleotide substitutions are in the third position of codons, bias in synonymous codon usage also reflects G + C content. The trpE-trp(G)D junction in the four organisms is characterized by overlapping translation termination and initiation codons. The relative positions of trpE and trp(G)D thus became fixed in evolution before the fusion of trpG and trpD. Nucleotide sequences representing the fusion of trpG and trpD in Escherichia, Shigella and Salmonella are not more nor less divergent than other portions of the trp(G)D coding sequences.     

Therapeutic value of indomethacin in threatened abortion

One hundred cases of threatened abortion were randomly allocated to four lines of treatment namely, long acting progesterone, antispasmodic, indomethacin and placebo. The lowest success rate was encountered in the indomethacin treated group; symptoms of intolerance were common and three cases out of sixteen turned into missed abortion. Indomethacin does not offer any advantage over other lines of treatment in threatened abortion.     

Isolubimin: A possible precursor of lubimin in infected potato slices

Potato slices treated with spirovetiva-1(10),11-diene-2-one yield lubimin and rishitin within 24 hr. A vetispirane which has not been detected in fungally infected potatoes was also isolated. This compound, isolubimin, appears to be an intermediate in the conversion of the above spirovetivone to lubimin.