The carpal tunnel syndrome as a probable primary deficiency of vitamin B6 rather than a deficiency of a dependency state

The mean basal specific activities and the mean % deficiencies of the activity of the glutamic oxaloacetic transaminase of the erythrocytes were identical (n.s.) for a group of eight patients with a severe carpal tunnel syndrome and for a group of eight university students. There was no significant difference in the increases in the specific activities for the patients and the students at 4 concentrations of pyridoxal 5′-phosphate. The apparent K_m for the patients and the students was 95 μM and 61 μM (n.s.) respectively. It is concluded from these data in conjunction with previous findings that the carpal tunnel syndrome is a deficiency disease of vitamin B₆, which is probably primary rather than one of a dependency state.     

Alcohol dehydrogenase isozymes in the mouse: Genetic regulation, allelic variation among inbred strains and sex differences of liver and kidney A2 isozyme activity

Genetic analysis of a proposed cis-acting temporal locus ( Adh-3t ), which regulates alcohol dehydrogenase C₂ (ADH-C₂) acitivity in mouse epididymis extracts, among F₁ (ddN × BALB/c) × ddN male backcross progeny provided evidence for genetic distinctness between the structural ( Adh-3 ) and temporal ( Adh-3t ) loci on chromosome 3. Genetic analysis also confirmed the close, linkage of Adh-1 (encoding liver and kidney ADH-A₂) and Adh-3 (encoding stomach ADH-C₂) to within 0.3 centimorgans on the mouse genome. Evidence is presented for a proposed closely linked cis-acting temporal locus (designated Adh-1t ) for the A₂ isozyme (encoded by Adh-1 ) controlling the activity of this enzyme in mouse kidney extracts, but having no apparent affect on liver and intestine ADH-A₂ activities. An extensive survey of the distribution of Adh-1, Adh-3 and Adh-3t alleles among 65 strains of mice is reported — with the exception of two Japanese strains (ddN and KF), linkage disequilibrium between Adh-3 and Adh-3t was observed. Sex differences in mouse liver and kidney ADH-A₂ activities were observed, with male/female ratios of approximately 0.6 and 3 respectively for these tissue extracts.     

The effects of pollution on Gammarus pulex (L) subsp,pulex (Schellenberg) in the inlet streams of Rostherne Mere,Cheshire

Two inlet streams, Rostherne Brook and the Southern Drain of Dolls Meadow, flowing into Rostherne Mere, Cheshire were sampled for macroinvertebrata, and their physical and chemical conditions analysed.The physical and chemical factors for these streams were similar, except for the stream beds and the pollution of Rostherne Brook. Both streams had large populations of Gammarus pulex and the life history of this organism was studied. The ratio of adult organism to juvenile diflered in the two streams, Rostherne Brook having a higher proportion of adults in winter and juveniles in summer as opposed to the Southern Drain in which a normal life history was exhibited.Experiments showed that these differences were not related to differences in stream bed conditions. It was considered that the different adult to juvenile ratios were therefore caused by pollution in Rostherne Brook. The juveniles were more tolerant to pollution and therefore more able to survive the summer when pollution effects were at a maximum.The life history was altered in Rostherne Brook by pollution. Instead of the dual life history produced by overwintering juveniles and speedy summer maturation, a simple alternation of juveniles and adults was seen.This change in life history enabled Gammarus to survive in the polluted waters of Rostherne Brook.

---

Resume Deux débouchés de ruisseaux, Rostherne Brook et le Southern Drain de Doll's Meadow, qui coulent tous les deux dans le lac de Rostherne dans le Cheshire, ont été échantillonnés pour y trouver des macroinvertébrés, et pour en analyser les conditions physiques et chimiques.On a trouvé semblables les éléments physiques et chimiques de ces ruisseaux, à l'exception du lit des deux ruisseaux et de la pollution de Rostherne Brook.Les deux ruisseaux avaient une population nombreuse de Gammarus pulex dont on a étudié le cycle d'évolution. On a trouvé une proportion différente d'organismes adultes et jeunes dans les deux ruisseaux: Rotherne Brook a une plus grande proportion d'adultes en hiver et de jeunes en été, pendant que Southern Drain montre un cycle normal des organismes.Des expériences ont prouvés que ces différences n'avaient aucun rapport à des différences de conditions du lit des ruisseaux. On a considéré que la pollution de Rostherne Brook a donc causé les proportions différentes d'adultes et de jeunes. Les jeunes toléraient mieux la pollution et pouvaient donc mieux survivre à l'été quand les effets de la pollution étaient au maximum.Le cycle d'évolution était changé dans Rostherne Brook par la pollution. Au lieu du double cycle d'évolution produit par les jeunes qui passaient l'hiver et par un développement rapide en été, on a découvert uniquement l'alternation de jeunes et d'adultes.Ce changement du cycle d'évolution a permis au Gammarus de survivre dans les eaux corrumpues de Rostherne Brook.

     

The effect of behavioural and morphological plasticity on foraging efficiency in the threespine stickleback (Gasterosteus sp.)

We conducted an experiment to assess the change in foraging efficiency resulting from diet-induced morphological and behavioural plasticity in a species of freshwater, threespine stickleback (Gasterosteus sp.). Different degrees of morphological and behavioural change were induced using two prey items commonly found in the diet of this species, allowing us to estimate the relative importance of each type of plasticity. The purpose of the experiment was twofold. First, earlier work had suggested that diet variability might be an important factor in the evolution of trophic morphological plasticity in sticklebacks. The present results extend this work by revealing the adaptive significance of morphological plasticity. The current experiment also qualitatively assessed the compatibility of the time scale of morphological change with that of the natural resource variability experienced by this species. The results indicate that diet-induced plasticity improves foraging efficiency continuously for up to 72 days of prey exposure. This is probably due in part to plasticity of the external trophic morphology but our results also suggest a complex interplay between morphology and behaviour. The time scale appears to be matched to that of natural diet variability although it is possible that some traits exhibit non-labile plasticity. Our discussion highlights the important distinction between conditions favouring the evolution of labile versus non-labile plasticity. The second objective of the experiment was to determine the relative importance of morphological and behavioural plasticity. Few studies have attempted to quantify the adaptive significance of morphological plasticity and no study to our knowledge has separated the effects of morphological and behavioural plasticity. Our experiment reveals that both behavioural and morphological plasticity are important and it also suggests a dichotomy between the two: behavioural plasticity predominately affects searching efficiency whereas morphological plasticity predominately affects handling efficiency.     

Conservation in structure of TOC1 transposons from Chlamydomonas reinhardtii.

TOC1 transposons from Chlamydomonas reinhardtii have an unusual arrangement of long terminal repeats. Polymorphic regions between TOC1 transposons were identified by restriction mapping on Southern blots. The variation in size of an internal MluI fragment defines two subclasses of TOC1 elements. Full-length cloned members of each subclass of TOC1 element were compared by electron microscope heteroduplex analysis. The cloned elements were co-linear over their entire length with no large sequence discontinuities. Base substitutions and small insertion/deletion events of less than 50 bp are responsible for forming the two subclasses of TOC1 elements.