Age differences in spatial positioning of males in a chimpanzee unit-group at the mahale mountains National Park,Tanzania

Proximity partner choice by male chimpanzees of various age classes was analyzed in relation to their spatial positioning. Field work was carried out twice at the Mahale Mountains National Park, Tanzania. Proximity data were recorded at 3 and 10m from the focal animal. The data for the proximity between the focal male and other individuals allowed the males to be classified into two categories according to both criteria: early adolescence to young adult, and prime to old age. Between the males, the 3m proximity data permitted a classification into two categories as above, but those for 10m did not. These two spatial distances thus probably have different meanings for the males. The numbers of male proximity partners and proximity with the alpha male also allowed the males to be classified into two categories: early and late adolescence, and young adult to old age. Together, the above results support the classification of males into three age-graded categories: (1) early and late adolescence, (2) young adult, and (3) prime to old age. This does not arise because the males of each category form an age group. Prime or older males are most frequently in proximity, while their juniors consistently attempt to approach them. However, even prime or older males are not equally in proximity with one another. Their proximity partners change as time passes. Probably recognizing such changes, they form coalitions or are in rivalry. The sexual interest of adolescent males is probably a factor stimulating them to separate from their mothers, and to approach older males. Young adult males, even though physically mature, do not have equal proximity relations with older males. They are not yet sufficiently qualified to join the coalitions formed by their seniors.     

Beneficial effect of ACE inhibitor in congestive heart failure

The effects of captopril, an angiotensin-converting enzyme inhibitor, on congestive heart failure (CHF) were investigated in animal and clinical studies. Congestive heart failure was induced in rats by a combination of pressure and volume overload. Cardiac pressure overload was induced by constricting one renal artery (Goldblatt rat) and volume overload was induced by aorto-caval fistula. Captopril (100 mg/kg/day) was then administered for 14 weeks. Isometric contraction was assessed using isolated left ventricular papillary muscles. The maximum developed tension and the maximum rate of increase in tension (dT/dtmax) were decreased in untreated rats with CHF and improved in captopriltreated rats. The left ventricular myosin isoenzyme pattern was shifted towards V3 in untreated rats with CHF, and was shifted back towards V1 in the captopril-treated rats. In the clinical study, captopril (37.5–75 mg/day) was administered to patients with cardiomyopathy for 12 months. There was no effect on left ventricular mass in hypertrophic cardiomyopathy, although systolic anterior motion of the mitral valve disappeared in one patient. In dilated cardiomyopathy, however, left ventricular mass tended to decrease. These results indicate that captopril has a beneficial effect in congestive heart failure.     

Isolation and chemical characterization of lipopolysaccharides from four Mycoplana species (M. bullata,M. segnis,M. ramosa and M. dimorpha)

Lipopolysaccharides (LPS), isolated from four Mycoplana species, i.e. the type strains of M. bullata, M. segnis, M. ramosa and M. dimorpha, were characterized onto their chemical composition and their respective lipid A-types. Those of M. bullata and M. segnis showed on DOC-PAGE an R-type character and had lipid A's of the Lipid A_DAG-type which exclusively contained 2,3-diamino-2,3-dideoxy-d-glucose as lipid A sugar. LPS's of M. ramosa and M. dimorpha showed, although only weakly expressed, ladder-like patterns on DOC-PAGE indicating some S-type LPS's and lipid A of the d-glucosamine type (Lipid A_GlcN). M. bullata LPS contained mannose and glucose in major amounts and additionally l-glycero-d-mannoheptose, whereas M. segnis LPS was composed of rhamnose, mannose and glucose together with both, d-glycero-d-manno- and l-glycero-d-manno-heptoses in a molar ratio of 1:2. All LPS's contained 2-keto-3-deoxy-octonic acid (Kdo), phosphate and an unidentified acidic component X. In addition to X, M. segnis LPS contained glucuronic and galacturonic acids, whereas M. ramosa LPS contained only galacturonic acid. Acetic acid hydrolysis of the LPS resulted in splitting off lipid A moieties, very rich in 3-hydroxy fatty acids, in particular in 3-OH-12:0 (in Lipid A_DAG), or in 3-OH-14:0 (in Lipid A_GlcN). Analysis of the 3-acyloxyacyl residues revealed major amounts of amide-linked 3-OH(3-OH-13:0)12:0 in lipid A of M. bullata and 3-OH(12:0)12:0 in lipid A of M. segnis. The rare 4-oxo-myristic acid (4-oxo-14:0) was observed only in M. bullata LPS, where it is ester-linked. Amide linked diesters could not be traced in M. ramosa and M. dimorpha. All four lipid A's lacked erster-bound acyloxyacyl residues.Non-standard abbreviations DAG 2,3-diamino-2,3-dideoxy-d-glucose - Kdo 2-keto-3-deoxy-octonate - LPS lipopolysaccharide - PITC phenyl isothiocyanate - NANA N-acetyl neuraminic acid     

Characterization of Borrelia Species Isolated from Ixodid Ticks,Ixodes ovatus

Thirty-two Borrelia isolates were obtained from the adult stage of ixodid ticks, Ixodes ovatus, collected in various localities in Japan. Borrelial isolates were cultivated and analyzed by polyacrylamide gel electrophoresis, with monoclonal antibodies, by pulsed field gel electrophoresis, and by genomic Southern hybridization. All borrelial isolates showed similar protein profiles and monoclonal antibody reactivities, while plasmid profiles were rather diverse. Genomic hybridization using rRNA gene probes demonstrated the genetic similarities of those isolates. We found no significant differences among the borrelial isolates tested, and the restriction fragment length polymorphism patterns of I. ovatus isolates were quite distinct from those of borrelial strains associated with Lyme disease. Therefore, the isolates of Borrelia obtained from I. ovatus were thought to fall into different genospecies.     

Mutations in the rfbT Gene Are Responsible for the Ogawa to Inaba Serotype Conversion in Vibrio cholerae O1

In cultures of Vibrio cholerae strains of Ogawa serotype, variant strains which had undergone serotype conversion from Ogawa to Inaba were identified. The rfbT genes cloned from the parent strains were found to produce a 31-kDa protein in the maxicell system, and to cause serotype conversion when introduced into E. coli cells expressing Inaba serotype specificity. On the other hand, rfbT genes cloned from the variant strains neither produced the 31-kDa protein nor caused serotype conversion. Nucleotide sequence of these rfbT genes as well as those of two clinical Vibrio cholerae strains of Inaba serotype revealed that mutations causing premature termination of their rfbT genes were invariably present in strains expressing Inaba serotype specificity. The result strongly suggested that genetic alteration of the rfbT gene is responsible for serotype conversion of Vibrio cholerae O1.     

Biosynthesis of brassinolide from castasterone in cultured cells of Catharanthus roseus

Feeding experiments with tritium- and deuterium-labeled castasterone (CS) were conducted with three cell lines of Catharanthus roseus, including crown gall cells and nontransformed cells. In all three cell lines, the conversion of CS to brassinolide (BL) was observed and unequivocally confirmed by gas chromatography/mass spectrometry (GC/MS). This is the first conclusive evidence that CS is the biosynthetic precursor of BL.Biosynthesis of brassinosteroids in Catharanthus roseus. Part II. Part I of this series: Yokota et al. (1990a).     

Gas chromatographic—mass spectrometric determination of tiopronin in human blood using acrylic acid esters as a derivatization reagent for the thiol group

A gas chromatographic—mass spectrometric method for determining tiopronin, which has a thiol group, in human blood has been described. To prevent the oxidative degradation of tiopronin in the blood, its thiol group was immediately protected by treatment with isobutyl acrylate, which reacted readily with tiopronin in a 0.1 M Na₂HPO₄ solution (pH 9.1). The reaction was quantitative within 30 min. The blood sample was deproteinized and purified by a combination of liquid—liquid extraction and solid-phase extraction. Finally, the carboxyl moiety of the ester adduct was derivatized to the pentafluorobenzyl ester. The derivatives of tiopronin and the internal standard were analysed with gas chromatography—mass spectrometry. The precision of the method was satisfactory, and the calibration curve had good linearity in the concentration range investigated. The limit of determination of tiopronin in blood was estimated to be ca. 1 ng/ml.     

Comparison of dispersal ability between the green leafhoppers,Nephotettix virescens andN. cincticeps (hemiptera: Cicadellidae) by tethered flight

Dispersal propensity of green leafhoppers was compared between a tropical species, Nephotettix virescens, and a temperate species, N. cincticeps. The flight ability was measured with tethered flight technique under laboratory conditions (25°C, 16L-8D). The pre-flight period was shorter and the flight duration was longer in N. virescens than in N. cincticeps in both sexes. No significant correlations were found between the flight activity and morphometric characters for either of the two species. The results suggested that dispersal propensity of N. virescens is higher than that of N. cincticeps.