β-thalassemia mutations in the Portuguese population

Summary In this study we have carried out haplotype analysis on the -globin gene cluster and characterized the -thalassemia mutation by oligonucleotide hybridization in 14 patients with thalassemia major and 5 with sickle cell/-thalassemia originating from southern Portugal. We found that three mutations, namely the °-39, ° IVS-1 nt 1 and ⁺ IVS-1 nt 110 are prevalent accounting for 53%, 32% and 10% of the -thalassemia chromosomes respectively. In general each mutation was associated with a specific chromosomal haplotype; the ° mutation, however, was linked to three different haplotypes. These results indicate that three oligo-probes complementary to the most common mutations allow prenatal diagnosis by oligonucleotide analysis in 96% of the couples at risk of having offspring with thalassemia major in southern Portugal.     

Binding of the galactose-specificPseudomonas aeruginosa lectin,PA-I,to glycosphingolipids and other glycoconjugates

The carbohydrate-binding specificity ofPseudomonas aeruginosa lectin I (PA-I) in iodinated or biotinylated form was studied. A large number of glycosphingolipids, as well as some glycoproteins and neoglycoproteins were used as ligands. Also, inhibition by free saccharides of PA-I binding to glycosphingolipids was tested. It was found that the lectin binds most strongly to terminal and nonsubstituted Gal3Gal- or Gal4Gal-structures.Abbreviations PA-I Pseudomonas aeruginosa lectin I - Cer ceramide - lactosylceramide Gal4GlcCer - iso globotriaosylcerami Gal3Gal4GlcCer - globotriaosylceramide Gal4Gal4GlcCer - globoside or globotetraosylceramide GalNAc3Gal4Gal4GlcCer - Forssman glycolipid GalNAc3GalNAc3Gal4Gal4GlcCer - P1 glycolipid Gal4Gal4GlcNAc3Gal4GlcCer - lactoneotetraosylceramide Gal4GlcNAc3Gal4GlcCer - B5 glycolipid Gal3Gal4GlcNAc3Gal4GlcCer - gangliotetraosylceramide Gal3GalNAc4Gal4GlcCer - GM1 Gal3GalNAc4(NeuAc3)Gal4GlcCer - RBC red blood cells - BSA bovine serum albumin - PBS phosphate-buffered saline - SDS sodium dodecyl sulfate - TLC thin-layer chromatography - HPLC high pressure liquid chromatography - MS mass spectrometry - FAB fast-atom bombardment - EI electron impact     

Diversity of the mouse T cell receptor Cγ1 gene: structural analysis in C57BL/Ka

We have isolated an unusual T cell receptor chain cDNA clone (7.1) from a library made from RNA derived from adult thymus of C57BL/Ka mice. This cDNA clone corresponds to the appropriately processed C1 constant region exons preceded by 1.5 kb of J-C1 intron. The 7.1 coding region is extremely homologous to the C1 gene of BALB/c mice, differing at the protein level by a single deletion (alanine 139) and a single substitution. This latter change eliminates the sole N-linked sugar attachment site, providing a basis for strain-specific glycosylation patterns. The J-C1 intronic region contains two DNA segments (termed J1 and J2) that are highly reminiscent of joining (J) segments; both have potentially functional recombination and donor splice sequences flanking an open reading frame. Northern analysis suggests that 7.1 may be derived from a large, variable region-containing precursor.     

The α and γ subunits of 7S nerve growth factor are present in excess concentrations in the mouse submandibular gland

Summary The 7S nerve growth factor molecule, found in the mouse submandibular gland, is comprised of three distinct protein subunits named , and -NGF. In this paper, radioimmunoassays specific for each subunit were used to measure the concentrations of these subunits in homogenates of mouse submandibular gland. It was determined that there were excess concentrations of both the and subunits, more than enough to bind all of the -NGF in the gland to form 7S-NGF. The radioimmunoassay data was confirmed by gel filtration experiments. In the gel filtration experiments, the excess and subunits eluted at positions which would indicate that these excess subunits were free and not bound in the 7S-NGF complex. The identity of the excess and subunits was substantiated by ion exchange chromatography, isoelectric focusing polyacrylamide gels and immunoblotting experiments. In conclusion, there are considerable quantities of and subunits present in the submandibular gland which are not bound to -NGE The functional significance of these excess concentrations of the and subunits is not known.     

Photoreversion und Photoprotektion bei UV-induzierten Mutationen des nichtphotoreaktivierbaren Bacteriums E.coli phr?

Summary Stationary phase cells of strain phr^–/MC 2 ofE. coli are not photoreactivable but the frequency of UV-induced mutations to low Streptomycine-resistance (S 3, 3/ml) is decreased strongly by illumination with light of fluorescence tubes (310 to 500 nm) after UV-irradiation. Also dark-reversion (DRM) of these mutations due to keeping UV-irradiated cells in saline is observed. Illumination before UV-irradiation decreases the frequency of the mutations (photoprotection against mutation=PPM) to the same extent as the combined action of photoreversion (PRM) and DRM. The lag-phase of cell division is prolonged strongly by illumination from 80 min without light to 150 min by the light-dose of highest activity. The additional lag is nearly the same if the illumination is done before, after or without UV-irradiation; this lag is about additive to the small lag caused by UV. Pre-illumination of the stationary-phase cells does not cause photoprotection against killing (PP), it even decreases the survival after high UV-doses. The observations support the hypothesis that PRM in this strain may be indirect, i.e. caused by the light-induced additional division lag which enhances the dark repair of UV-premutations. Also spontaneous premutations which are apparently present in the stationary-phase cells seem to be influenced by the light in this way.     

Diel Movements of Bat Rays, Myliobatis californica, in Tomales Bay, California: Evidence for Behavioral Thermoregulation?

We used ultrasonic telemetry to examine movement patterns of 11 bat rays, Myliobatis californica, in Tomales Bay, California. Tomales Bay is long (20km) and narrow (1.4km), and is hydrographically separated into outer and inner bay regions. The outer bay (the outermost 8km) is characterized by oceanic conditions while the shallow inner bay (the innermost 12km) features wide seasonal temperature shifts. Five rays were tracked monthly from October 1990 to November 1991 and six rays (four of which carried temperature-sensing transmitters) were tracked daily from 30 June to 16 July 1992. Mean bat ray movement rate was 8.84mmin^–1 (range 4.49 to 13.40mmin^–1) and was not significantly affected by size (p=0.592), tidal stage (p=0.610), or time of day (p=0.327). Movement direction was unrelated to tidal stage (p=0.472) but showed a highly significant diel pattern (p<0.001). From 2:50–14:50h, rays moved toward the warmer and shallower inner bay, while from 14:50–2:50h they moved toward the cooler and deeper outer bay. These telemetry data, along with known bat ray foraging patterns and respiratory temperature-sensitivity, argue for behavioral thermoregulation as the primary influence on this movement pattern.     

The carotenoids of Flavobacterium strain R1560

The main carotenoid of Flavobacterium strain R1560 has been identified as (3R,3R)-zeaxanthin. Also present were small amounts of 15-cis-phytoene, phytofluene, -carotene (7,8,7,8-tetrahydro-, -carotene plus 7,8,11,12-tetrahydro-, -carotene), neurosporene, lycopene, -zeacarotene, -carotene, -carotene, -cryptoxanthin, rubixanthin, 3-hydroxy--zeacarotene and several apo-carotenals. Zeaxanthin production was inhibited by nicotine (10 mM), and lycopene and rubixanthin accumulated. The biosynthesis of zeaxanthin is discussed in terms of pathways and also of half-molecule reaction sequences. The presence of zeaxanthin may be a characteristic of a group of Flavobacterium species, and may thus be useful in the taxonomic classification of these organisms.     

Computerized scheme for the reaction of hemoglobin with ligands

A scheme for the reaction of hemoglobin with ligands is described, which postulates the functional heterogeneity of the chains, considers all possible combinations of the distribution of the ligand on the four chains of hemoglobin, and does not require simplifying assumptions about the hemoglobin reactivity. Ten tetrameric species are considered, together with 16 reactions between these species, each with an on and an off rate constant. The dissociation of hemoglobin tetramers into dimers is also considered, with four on and four off rate constants for the reactions between dimers, and ten equilibrium constants for the reactions between tetramers and dimers. Moreover, some side reactions, such as the trapping of ligands by a hemoglobin competitor, are included. A FORTRAN program, suitable for microcomputers, is described for handling this scheme, with some examples showing its advantages.     

Die bursa- und schwanzstrukturen und ihre aberrationen bei den strongylina (Nematoda) morphologische studien zum problem der pluri-und paripotenzerscheinungen

Zusammenfassung In der Einleitung ist das Ziel der Arbeit in den wesentlichsten Punkten herausgestellt.Die Bursastrukturen (Bursavelum und Rippen bzw. Papillen) der parasitischen Strongylina lassen sich von den entsprechenden Bildungen der freilebenden Rhabditina, vor allem der Gattung Rhabditis, ableiten und in ihren Einzelgliedern homologisieren.Die im Laufe der Phylogenie bei den Strongylina auftretenden strukturellen Transformationen lassen sich auf einige wenige, relativ einfache morphogenetische Grundvorgänge zurückführen, die da sind: Wachstumsallometrien, Materialkompensationen, Organverschmelzungen und Spaltungen (Fissationen), Rudimentationen und ähnliche Vorgänge.Innerhalb der Strongylina Bursa ist ein Gefälle der Wachstumsgradienten feststellbar, das sich vom Zentrum der Bursa sowohl nach distal als auch proximalwärts abschwdcht. Zunehmende Förderung der zentral gelegenen Organe (Rippen) führt zu entsprechender Reduktion der peripheren Bursastrukturen, was vor allem im terminalen Schwanzabschnitt auffällt und zur Ausbildung des oft nur noch als Rudiment vorhandenen Dorsalrippenkomplexes führt. Letzterer entspricht in seiner Gesamtheit der Schwanzspitze der peloderen Rhabditiden mit den Papillen 9 und 10.Die bei Rhabditis moist getrennten Papillen 7 und 8 sind bei allen Strongylina zu einer Rippe (Externodorsal-Rippe) verschmolzen, die jedoch in manchen Aberrationen durch Abspaltung eines akzessorischen Astes ihre wahre Natur (als Verschmelzungsprodukt) zu erkennen gibt (Atavismus).Da dieselben Transformationsvorgänge innerhalb der Strongylina mehrfach unabhängig voneinander wirksam geworden sind, treten bestimmte Strukturformen als Parallelbildungen in verschiedenen phylogenetischen Union auf (polytope Entstehung).Zahlreich untersuchte Bildungsabweichungen (Aberrationen), deren Bedeutung für die Morphologie kurz umrissen wird, erschöpfen sich in den gleichen strukturellen Transformationstypen, die auch bei der Evolution der verschiedenen Union der Strongylina nachweisbar sind. Die Aberrationen führen daher häufig zu Atavismen oder zu Parallelvariationen (homologe Variationen").Die Zahl der Umwandlungsmbglichkeiten (Potenzen) der Bursastrukturen innerhalb der Strongylina ist beschränkt (Paripotenz im Sinne Haeckers). Bestimmte Arten (und Entwicklungshnien) haben jeweils nur bestimmte Potenzen realisiert. Andere können jedoch latent (virtuell) im Kryptotypus vorhanden sein, ohne normalerweise in Erscheinung. zu treten. In bestimmten Aberrationen können sie jedoch plötzlich realisiert werden, so ihr latentes Vorhandensein demonstrierend (Pluripotenz).Wie lange bestimmte Potenzen in einer Gruppe erhalten bleiben konnen, verdeutlichen auch die Schwanzhocker weiblicher Nematoden, als zum Bauplan der Nematoden gehbrende Bildungen. Die Potenz zur Ausbildung dieser Strukturen kommt offensichtlich sehr vielen Nematoden-Arten zu, wird jedoch nur in relativ wenigen Fällen, aber innerhalb der verschiedenen Gruppen bald hier, bald dort (disjunkte Verbreitung), realisiert. Es handelt sich bei den Schwanzhöckern um rudimentäre Organe, die bei keiner Nematoden-Art mehr voll ausgebildet erhalten sind. Ihre Rudimentation beruht zum Teil auf Materialentzug, als Folge von Unkonstruktionen der Schwanzregion, wobei die Adultstadien zuerst betroffen werden (Aphanisie nach Sewertzoff).Bei den in Chiropteren parasitierenden Strongylacanthinae haben sich Schwanzhöcker noch bei allen Arten erhalten, was ein offensichtlich archaisches Merkmal darstellt. Bei anderen Nematoden, denen sie nur im Larvalstadium zukommen, treten sie wohl durch Fötalisation in seltenen Fällen auch bei den adulten Stadien wieder auf.Alle speziellen Bursaformen der Strongylina lassen sich durch relativ wenige und einfache Transformationsvorgänge aus einem durch Abstraktion gewonnenen diagrammatischen Typus ableiten (Prinzip der variablen Proportionen" nach Troll).Die typisierten Umwandlungsvorgänge decken sich weitgehend mit den von Remane allgemein gefaßten strukturellen Typen der Realmutationen. Da sie bei den beobachteten Aberrationen, deren Entstehung auf dem Wege über Realmutationen sehr wahrscheinlich ist, in homologer Weise auftreten, kann das innerhalb der Strongylina zu beobachtende Evolutionsphänomen auf Realmutationen zurückgeführt warden.Obwohl sich die untersuchten strukturellen Transformationen in dem systematisch relativ wait gefaßten Rahmen einer Unterordnung abspielen (transspezifische Evolution nach Rensch), handelt es sich bei der von uns bevorzugten Terminologie (nach Woltereck und Remane), unter Berücksichtigung des Charakters der Umwandlungen, doch nur um Vorgänge, die in den Bereich der Mikroevolution fallen.     

A model of associative memory in the brain

A model of associative memory for time varying spatial patterns is proposed and simulated on a digital computer. This is a network composed of many neuron-like elements, and shows an ability for associative memory similar to that of the brain.Suppose a number of sequences of spatial patterns are presented to this network, for example, 12345, ABC, and so on. Then, these patterns are memorized in the network. After that, if any part of one of these sequences, say 23, is presented to the circuit, the rest of the sequence, 45, is recalled following to it. It resembles to such a situation — if we hear a part of a melody which we have memorized in the past, the rest of the melody is recalled even after it is stopped half-way. Although the recalled patterns are not always 100% correct, they are not completely destroyed even if the presented patterns are imperfect.     

Extent and high frequency of a short conversion between the human Aγ and Gγ fetal globin genes

Summary Southern blotting and DNA sequencing after polymerase chain reaction (PCR) amplification provide evidence for the frequent occurrence (in 7 out of 24 chromosomes) of a short conversion GA in the 3 end of the human fetal A globin gene. This short conversion is characterized by the presence, 3 nucleotides downstream from the termination codon of the A gene, of the TCAC sequence that is normally present at the equivalent position at the 3 end of the G gene; it is therefore identical to a conversion already described. Interestingly, we have found that this conversion is associated with the presence of theHindIII polymorphic restriction site in the A IVS2, occuppying an equivalent position in both the G and A genes. Our observations strengthen the hypothesis that the presence of the HindIII polymorphic restriction site in A IVS2 and the presence of the sequence TCAC at the 3 end of the A gene might be the result of a single conversion event.     

Utilization and degradation of lindane by soil microorganisms

Of 147 microorganisms isolated from a loamy sand, 71 showed good growth with lindane (-1,2,3,4,5,6-hexachlorocyclohexane) and produced chloride in an aqueous medium. Thirteen soil microorganisms were selected to study the utilization of lindane. Lindane was metabolized by the microbes to -2,3,4,5,6-pentachloro-1-cyclohexene (-PCCH), -3,4,5,6-tetrachloro-1-cyclohexene (-TCCH), -3,4,5,6-tetrachloro-1-cyclohexene (-TCCH), -3,4,5,6-tetrachloro-1-cyclohexene (-TCCH), and pentachlorobenzene (PCB). Cells of Pseudomonas sp. No. 62 grown on lindane simultaneously adapted to -PCCH, -TCCH, -TCCH, -TCCH, PCB, 1,2,3,4-tetrachlorobenzene (1,2,3,4-TCB) and 1,2,4,5-tetrachlorobenzene (1,2,4,5-TCB). The bacteria degraded each of these chemicals at least partially as indicated by an increased rate of oxygen consumption.Abbreviations Lindane -1,2,3,4,5,6-hexachlorocyclohexane - -PCCH -2,3,4,5,6-pentachloro-1-cyclohexene - -TCCH -3,4,5,6-tetrachloro-1-cyclohexene - -TCCH -3,4,5,6-tetrachloro-1-cyclohexene - -TCCH -3,4,5,6-tetrachloro-1-cyclohexene - PCB pentachlorobenzene - 1,2,3,4-TCB 1,2,3,4-tetrachlorobenzene - 1,2,3,5-TCB 1,2,3,5-tetrachlorobenzene - 1,2,4,5-TCB 1,2,4,5-tetrachlorobenzene - 1,2,3-tCB 1,2,3-trichlorobenzene - 1,2,4-tCB 1,2,4-trichlorobenzene - 1,3,5-tCB 1,3,5-trichlorobenzene - 1,2-DCB 1,2-dichlorobenzene - 1,3-DCB 1,3-dichlorobenzene - 1,4-DCB 1,4-dichlorobenzene - MCB monochlorobenzene Contribution No. 631, Research Institute, Agriculture Canada, University Sub Post Office, London, Ontario N6A 5B7     

Synthesis of Gal-β-(1→4)-GlcNAc-β-(1→6)-[Gal-β- (1→3)]-GalNAc-α-OBn oligosaccharides bearing O-methyl or O-sulfo groups at C-3 of the Gal residue: specific acceptors for Gal: 3-O-sulfotransferases

Our recent studies have revealed the existence of two distinct Gal: 3-O-sulfotransferases capable of acting on the C-3 position of galactose in a Core 2 branched structure, e.g., Gal14GlcNAc16(Gal13)GalNac1OBenzyl as acceptor to give 3-O-sulfoGal14GlcNAc13(Gal13)GalNAc1OB 20 and Gal14GlcNAc16(3-O-sulfoGal13)GalNAc1OB 23. We herein report the synthesis of these two compounds and also that of other modified analogs that are highly specific acceptors for the two sulfotransferases. Appropriately protected 1-thio-glycosides 7, 8, and 10 were employed as glycosyl donors for the synthesis of our target compounds.     

Notes on the Mechanism of ATP Synthesis

The most commonly quoted mechanism of the coupling between the electrochemical proton gradient and the formation of ATP from ADP and P_i assumes that all states of the F₁ portion of the ATP synthase have subunits in tight, loose, and open conformations. Models based on this assumption are inconsistent with some of the available experimental evidence. A mechanism that includes an additional subunit conformation, closed, observed in the rat liver structure overcomes these difficulties.     

Restriction in the conformational flexibility of apoproteins in the presence of organic cosolvents: a consequence of the formation of "native-like conformation".

The influence of n-propanol on the overall -helical conformation of -globin, apocytochrome C, and the functional domain of streptococcal M49 protein (pepM49) and its consequence on the proteolysis of the respective proteins has been investigated. A significant amount of -helical conformation is induced into these proteins atpH 6.0 and 4°C in the presence of relatively low concentrations of n-propanol. The induction of -helical conformation into the proteins increased as a function of the propanol concentration, the maximum induction occurring around 30% n-propanol. In the case of -globin, the fluorescence of its tryptophyl residues also increased as a function of n-propanol concentration, the midpoint of this transition being around 20% n-propanol. Furthermore, concomitant with the induction of helical conformation into these proteins, the proteolysis of their polypeptide chain by V8 protease also gets restricted. The -helical conformation induced into - and -globin by n-propanol decreased as the temperature is raised from 4 to 24°C. In contrast, the -helical conformation of both - and -chain (i.e., globin with noncovalently bound heme) did not exhibit such a sensitivity to this change in temperature. However, distinct differences exist between the n-propanol induced -helical conformation of globins and the -helical conformation of - and -chains. A cross-correlation of the n-propanol induced increase in the fluorescence of -globin with the corresponding increase in the -helical conformation of the polypeptide chain suggested that the fluorescence increase represents a structural change of the protein that is secondary to the induction of the -helical conformation into the protein (i.e., an integration of the helical conformation induced to the segments of the polypeptide chain to influence the microenvironment of the tryptophyl residues). Presumably, the fluorescence increase is a consequence of the packing of the helical segments of globin to generate a native-like structure. The induction of -helical conformation into these proteins in the presence of n-propanol and the consequent generation of native-like conformation is not unique to n-propanol. Trifluoroethanol, another helix-inducing organic solvent, also behaves in the same fashion as n-propanol. However, in contrast to the proteins described above, n-propanol could neither induce an -helical conformation into performic acid oxidized RNAse-A nor restrict its proteolysis by proteases. Thus, the high sensitivity of apoproteins and the protein domains to assume -helical conformation in the presence of low concentration of n-propanol with a concomitant restriction of the proteolytic susceptibility of their polypeptide chain appears to be unique to those proteins that exhibit high -helical propensities. Apparently, this phenomenon of helix induction and the restriction of proteolysis reflects the formation of rudimentary tertiary interaction of the native protein and is unique to apoproteins or structural domains of -helical proteins. Consistent with this concept, the induction of -helical conformation into shorter polypeptide fragments of 30 residues, (e.g., _1-30, which exists in an -helical conformation in hemoglobin) is very low. Besides, this peptide exhibited neither the high sensitivity to the low concentrations of n-propanol seen with the apoproteins/protein domains nor the resistance toward proteolysis. The results suggest that the organic cosolvent induced decrease in the conformational flexibility of the apoprotein, and the consequent restriction of their proteolytic cleavage provides an opportunity to develop new strategies for protease catalyzed segment condensation reactions.     

Thermophilic and mesophilic bacteria in biofilms associated with corrosion in a heat exchanger

Biofilm development on AISI-1020 carbon steel coupons installed at the outlet of a heat exchanger was evaluated at the thirtieth and the sixtieth days of exposure. Water temperature varied between 41 and 60°C. The most probable number technique (MPN) was applied to quantify mesophilic and thermophilic species of aerobic, anaerobic, and sulphate-reducing bacteria (SRB) in planktonic and sessile phases. The results showed predominance of thermophilic aerobic bacteria in both phases, corresponding to 9.5±0.8×10⁶cells/ml in the planktonic phase. In biofilms, maximal aerobic cell concentration, 7.8±0.6×10⁸cells/cm2, was registered at the sixtieth day. An increase in the number of thermophilic anaerobic and SRB with elapsed time was also observed. The results obtained after 60 days were 5.8±0.4×10⁷ and 8.9±0.9×10⁴cells/cm² for anaerobic and sulphate-reducing bacteria, respectively. Scanning electron microscopy showed a varied composition of species in the biofilms and corrosion on the carbon steel surfaces after biofilm removal.     

Partial mispairing and crossing-over between β0 and δ genes as the origin of the δ β0 thalassemia gene

Summary Two double heterozygous ⁰/⁰ thalassemic sibs of Mexican descent were studied. The father had a ⁰/⁰ genotype, while the mother, one sib and several maternal relatives were ⁰/⁰ heterozygotes. Parental consanguinity and an apparently low frequency of thalassemia among Mexicans suggested a possible common origin of both ⁰ and ⁰ genes. A hypothesis to explain such a possibility is proposed on the basis of a partial mispairing between ⁰ and genes followed by a crossing-over which would results in a ⁰ recombinant gene. This hypothesis could also be extended to explain the 22 gluala, 22 alaglu and 116 arghis Hb variants as recombinants from double crossing-over between and mispaired genes for which the name interstitial-Lepore is proposed.     

Aluminum-induced secretion of both citrate and malate in rye

Aluminum (Al)-resistant mechanisms responsible for Al-induced secretion of organic acids are poorly understood. In this study, we characterized the Al-induced secretion of both citrate and malate from rye (Secale cereale L. cv. King). Secretion of organic acids increased with increasing concentration (10, 30 and 50 M) and duration of Al treatments. Neither phosphorous (P) deficiency up to 15 days nor addition of 50M lanthanum, 50 M lead, 10 M cadmium, or 200 M manganese caused secretion of organic acids, suggesting that this secretion was a specific response to Al stress. Aluminum activated citrate synthase, the main enzyme for the synthesis of citrate, but its activation occurred only in the root tip. The elongation of roots of an Al-sensitive cultivar of wheat (Tritium aestivum L. cv. Scout 66) was not inhibited by 50 M Al in the presence of externally applied 50 M citrate or 400 M malate. The secretion of citrate and malate from intact rye roots exposed to 50 M Al corresponded to 31.3 ± 1.7 M and 11.5 ± 2.5 M, respectively, in the rhizosphere based on an assumption of a 2 mm thick unstirred layer around root tips. This result indicated that Al-resistance in rye was achieved by the Al-induced synthesis of citrate in root apices followed by Al-induced specific secretion of citrate from root tips.     

Idioms of distress: Kinship and sickness among the people of the Kingdom of Tonga

Idioms of distress refers to the popular expression of emotional tension that arises in the relationship between sickness and kinship. By reference to case studies and discussions among the Polynesian people of Tonga, the author shows where such tension arises and how it influences the sickness process. Sickness is necessarily a collective phenomenon which can best be understood not simply as a clinical event, but as an experience that is part of the experience of family. Various ways of expressing distress as a reflexive encounter between personal and cultural meaning systems are reviewed, as are several new concepts such as doing sickness as kinship, and turning in the process of decision making in the kinship management of sickness. The explanatory models of sickness in Tonga are shown to encompass culturally sanctioned expressions of distress as part of the adaptive coping mechanisms in that society. Distress frequently emerges in somatic form, as a number of studies have shown. However, the author emphasizes the kinship meaning of sickness, kinship management and sickness therapy, the adaptive process of idiomatic expressions of distress, which are expanded here and offered as potential avenues for elaboration in other cultural milieu. Two aspects of the notion idioms of distress are noted, and the phenomenon is understood as a process which acts as a prime mover in social change.     

Abscisic acid as an endogenous component in lettuce fruits,Lactuca sativa L. cv. Grand Rapids. Does it control thermodormancy?

Summary Abscisic acid (ABA) has been unequivocally identified as an endogenous component of seeds of Grand Rapids lettuce. Both free and bound ABA levels were followed during imbibition at various temperatures but no clear role for ABA in the imposition of thermodormancy emerged. Furthermore it was apparent that different seed batches showed different ratios of free to bound ABA and patterns of changes. An unsuccessful attempt was made to identify bound ABA, presumed to be the glucosyl ester.Abbreviations ABA abscisic acid - ABA Me ester methyl abscisate - ECD electron capture detector - FID flame ionisation detector - GC-MS combined gas liquid chromatography, mass spectrometry - GLC gas liquid chromatography - PVP polyvinyl-pyrrolidone - TLC thin layer chromatography