Frequency of large granular lymphocytes in peripheral blood of healthy persons and breast cancer patients

Summary The frequency of large granular lymphocytes (LGL) in the peripheral blood of healthy persons (n=56) and breast cancer patients (31 cases with stage-I and -II disease and 42 cases with stage-III and -IV disease) was studied. The frequency of LGL in peripheral blood was significantly depressed in cancer patients, and particularly in patients with advanced breast cancer.     

Modulation of the beta-adrenergic response in cultured rat heart cells

Incubation of rocker-cultured neonatal rat heart cells with 3 mM L(+)-lactate led to a sharp increase in the sensitivity of cardiomyocytes to the beta-adrenergic agonist isoprenaline, as measured by their chronotropic response. This effect was accompanied by a reduction in the arachidonic acid content of the total phospholipids. The phospholipase A₂-activator melittin as well as free arachidonic acid induced this supersensitivity to the same degree. On the other hand, the L(+)-lactate-evoked supersensitivity could be blocked by the phospholipase A₂ inhibitors mepacrine and n-bromophenacyl-bromide, suggesting an involvement of phospholipase A₂ in the process of beta-adrenergic sensitization. The sensitizing action of arachidonic acid was blocked by the lipoxygenase inhibitors esculetin and nordihydroguaiaretic acid, but not by the cyclooxygenase inhibitor indomethacin. Supersensitivity was likewise evoked by 15-S-hydroxyeicosatetraenoic acid (15-S-HETE), but not by 5-S-HPETE or 5-S-HETE. These findings suggest that the phospholipase A₂-15-lipoxygenase pathway plays a role in the induction of beta-adrenergic supersensitivity in the cultured cardiomyocytes and point to a new physiological role of the lipoxygenase product 15-S-HETE.Abbreviations NDGA nordihydroguaiaretic acid - HETE hydroeicosatetraenoic acid - HPETE hydroperoxyeicosatetraenoic acid     

Fragmenta mycologica

Summary The historical developmental stages of the hairbaiting technique are traced through the past decades.Since three investigators have substantially contributed to the development of this technique, it is proposed that this technique should in the future be known as theToma-Karling-Vanbreuseghem hairbaiting method or abbreviated as in the anagram: ToKaVa-hairbaiting method.

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Zusammenfassung Die historischen Entwicklungsstufen der Haarköder-Methode werden durch die Jahrzehnte verfolgt.Da drei Forscher zum Aufbau dieser Methode am wesentlichsten beigetragen haben, wird es vorgeschlagen, dass diese Methode in Zukunft als dieToma-Karling-Vanbreuseghem Haarköder-Methode benannt werde oder kurz, mit einem Anagramm, als die ToKaVa-Haarködermethode.

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Résumé L'auteur discute les étapes historiques du développement de la méthode en usant la kératinophilie des dermatophytes pour les cultiver.Puisqu'il y a trois investigateurs qui ont contribué, par excellence, au développement de cette méthode, on propose que cette téchnique soit dénommée au future comme d'appât de cheveux deToma-Karling-Vanbreuseghem ou, bref, la méthode d'appât de cheveux de ToKaVa.

     

Sterols and frost hardening of winter rape

Winter rape ( Brassica napus L., var. olifera cv. Górczanski) seedlings were exposed to hardening conditions and the content and composition of free sterols as well as the ratio of free sterols to total phospholipids were determined. There was a reduction in free sterol content in the leaves at the most advanced stage of hardening. The ratio of free sterol to total phospholipids was significantly reduced by hardening due to a decrease in the level of the former and an increase in that of the latter compounds. There was a negative correlation between this ratio and the temperature at which half of the seedlings died. Thus, adaptation of membranes to temperature takes place also at the level of sterol-phospholipid interactions. Exposing seedlings already hardened to freezing temperatures caused injury higher than 50%, and brought about a drastic increase in the level of free sterols and an elevation in the ratio of free sterols to phospholipids. The results are discussed in terms of a possible role of the molecular architecture of membranes in surviving at subzero temperatures.     

Nocturnal parasitism of moth eggs by Trichogramma wasps

Parasitoid wasps of the genus Trichogramma are used worldwide as biological control agents against lepidopteran pests. Trichogramma wasps develop inside eggs of a wide range of host species, most of them moths. They are generally considered as diurnal insects. Here, we investigated whether Trichogramma wasps can also successfully parasitise host eggs at night under controlled laboratory conditions. Eggs of the moth Ephestia kuehniella were offered under dark conditions (scotophase) to females of Trichogramma brassicae and Trichogramma evanescens either from 9:00 PM to 9:00 AM or from 11:00 AM to 5:00 PM at four different temperatures (5°C, 10°C, 15°C and 20°C). Both species are known to parasitise E. kuehniella eggs in the photophase during daytime. The results show that T. brassicae did not parasitise eggs in the scotophase at night and only very few in the artificially induced scotophase during daytime from 10°C to 20°C. In contrast, T. evanescens parasitised more eggs in the dark both at night and artificially induced scotophase during daytime. Parasitism in the scotophase already started at 5°C, with more eggs being parasitised and more offspring being produced at higher temperatures. T. evanescens displayed higher parasitism activity in the induced scotophase during daytime than in the scotophase at night. The present study suggests that Trichogramma are capable of successfully parasitising host eggs at night, even at low temperatures, but that nocturnal activity with respect to parasitism varies between wasp species.     

Between‐male variation in sperm size,velocity and longevity in sand martins Riparia riparia

Sperm mobility is known to be an important determinant of a male's sperm competitive ability. Although more debated, sperm length and its relation to sperm swimming ability has also been proposed to determine a male's fertilisation potential. Furthermore, both mobility and length may covary with a male's phenotype, either positively (the phenotype‐linked fertility hypothesis) or negatively if, for instance, low‐quality males have less access to females but invest more in sperm production. Using dummy females, we collected sperm samples from wild sand martins Riparia raparia males. We investigated the relationship between sperm length and sperm swimming speed as measured by sperm straight line velocity (VSL), and determined whether sperm traits are correlated with male body size and condition. We found that total sperm length is repeatable within‐ejaculate and shows substantial inter‐male variation. Sperm length was associated with sperm velocity: males with short sperm have sperm that swim initially faster but die sooner, whereas males with longer sperm have sperm that swim more slowly but for a longer time. Smaller males produced sperm with higher overall velocity. This correlation between male size and sperm behaviour may reflect alternative fertilisation strategies where small males having less mating opportunities invest more in sperm competitive ability. The existence of such alternative strategies would participate in maintaining variation in sperm length and velocity in this species.     

Brain‐derived neurotrophic factor selectively regulates dendritogenesis of parvalbumin‐containing interneurons in the main olfactory bulb through the PLCγ pathway

Molecular mechanisms of neurotrophin signaling on dendrite development and dynamics are only partly understood. To address the role of brain‐derived neurotrophic factor (BDNF) in the morphogenesis of GABAergic neurons of the main olfactory bulb, we analyzed mice lacking BDNF, mice carrying neurotrophin‐3 (NT3) in the place of BDNF, and TrkB signaling mutant mice with a receptor that can activate phospholipase Cγ (PLCγ) but is unable to recruit the adaptors Shc/Frs2. BDNF deletion yielded a compressed olfactory bulb with a significant loss of parvalbumin (PV) immunoreactivity in GABAergic interneurons of the external plexiform layer. Dendrite development of PV‐positive interneurons was selectively attenuated by BDNF since other Ca²⁺‐binding protein‐containing neuron populations appeared unaffected. The deficit in PV‐positive neurons could be rescued by the NT3/NT3 alleles. The degree of PV immunoreactivity was dependent on BDNF and TrkB recruitment of the adaptor proteins Shc/Frs2. In contrast, PLCγ signaling from the TrkB receptor was sufficient for dendrite growth in vivo and consistently, blocking PLCγ prevented BDNF‐dependent dendrite development in vitro. Collectively, our results provide genetic evidence that BDNF and TrkB signaling selectively regulate PV expression and dendrite growth in a subset of neurochemically‐defined GABAergic interneurons via activation of the PLCγ pathway. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006     

Isolation and partial characterization of basic proteinases from stem bromelain

Crude bromelain extracts from pineapple stems (Ananas comosus) were fractionated by two-step FPLC-cation-exchange chromatography. At least eight basic proteolytically active components were detected. The two main components F4 and F5 together with the most active proteinase fraction F9 were characterized by SDS-PAGE, mass spectroscopy, multizonal cathodal electrophoresis, partial amino acid sequence, and monosaccharide composition analysis. F9 amounts to about 2% of the total protein and has a 15 times higher specific activity against the substratel-pyroglutamyl-l-phenylanalyl-l-leucine-p-nitroanilide (PFLNA) than the main component F4. The molecular masses of F4, F5, and F9 were determined to 24,397, 24,472, and 23,427, respectively, by mass spectroscopy. Partial N-terminal amino acid sequence analysis (20 amino acids) revealed that F9 differs from the determined sequence of F4 and F5 by an exchange at position 10 (tyrosineserine) and position 20 (asparagine glycine). F4 and F5 contained fucose, N-acetylglucosamine, xylose, and mannose in ratio of 1.02.01.02.0, but only 50% of the proteins seem to be glycosylated, whereas F9 was found to be unglycosylated. Polyclonal antibodies (IgG) against F9 detected F4 and F5 with tenfold reduced reactivity. ThepH optimum of F4 and F5 was betweenpH4.0 and 4.5 and for F9 close to neutralpH. The kinetic parameters for PFLNA hydrolysis were similar for F4 (K _m 2.30 mM,k _cat 0.87 sec^–1 and F5 (K _m 2.42 mM,k _cat 0.68 sec^–1), and differed greatly from F9 (K _m 0.40 mM,k _cat 3.94 sec^–1).Dedicated to H. Tschesche, Bielefeld, Germany, on behalf of his 60th anniversary.