The influence of environmental factors on dormancy and duration of egg development in Metrioptera roeseli (Orthoptera: Tettigoniidae)

Summary Developing eggs of Metrioptera roeseli HGB. have an obligate embryonic diapause in stage 23 and a facultative initial diapause in stage 4. Initial diapause is lacking when the ovipositing females are kept at long day photoperiod (LD 16/8), but is induced at LD 14/10 and LD 8/16. When natural light conditions are given in the laboratory, the females mostly lay diapausing eggs from the end of August onwards. In eggs without initial diapause, a larger number of embryos reach a stage, in which the embryonic diapause can be broken by chilling, only at favorable temperature (4 weeks at 24°C or 8 at 18°C) and in contact with water before the first winter. Thus, some individuals of a given population of M. roeseli have an annual, others a biennial life cycle. The variability in the duration of egg development is due to a photoperiodically induced, facultative initial diapause and to a possible quiescence caused by insufficient temperature and/or moisture.     

Psychological changes associated with self-regulatory treatments of irritable bowel syndrome

The psychological side effects of self-regulatory treatment (a combination of relaxation, thermal biofeedback, and cognitive therapy) for irritable bowel syndrome (IBS) were compared among 20 successfully treated patients, 12 unsuccessfully treated patients, and 9 patients who merely monitored symptoms for 12 weeks. Pretreatment and posttreatment scores on the Beck Depression Inventory, State-Trait Anxiety Inventory, and Psychosomatic Symptom Checklist were examined. Successfully treated patients had significant (p<.01) reductions on all measures and significantly greater reductions on depression and state anxiety than the symptom monitoring group. Interestingly, the failures also showed a significant (p=.027) reduction in trait anxiety and no significant increases on other measures.     

INFLUENCE DU SUPERPARASITISME SUR LA DURÉE DU DÉVELOPPEMENT LARVAIRE ET LE POIDS DU PARASITOÏDE LIXOPHAGA DIATRAEAEÉLEVÉ DANS UN HÔTE DE SUBSTITUTION GALLERIA MELLONELLA

Résumé G. mellonella infestée au dernier stade larvaire avec 1, 2, 3 ou 5 planidia/hôte (ph/H) produit 1 à 5 pupes/hôte (pu/H). La mortalité des chenilles augmente avec le nombre de pl/H. Le poids des pupes et décroît avec un nombre croissant de pu/H (18,2 à 12,9 mg pour les et 12,5 à 9,7 mg pour les ). Le développement larvaire dure 8,7 j. chez les et 8,3 chez les ; il est peu affecté par le superparasitisme. Avec 1, 2, 3 et 5 pl/H nous obtenons 0,84–1,61–2,17 et 3,43 pu/H et 0,81–1,48–2,10 et 3,11 imagos/H. L'optimum est de 3 pl/H ou 1 à 2=pl/H pour obtenir des parasitoïdes plus lourds.

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Summary The influence of superparasitism on larval and pupal development is investigated. Last-larval instar G. mellonella (200±5 mg) were infected with 1, 2, 3 or 5 planidia/host (pl/H) producing 1 to 5 pupae per host (pu/H). Host mortality (8.6–8.3–14.3 and 22.2%) increased with the number of planidia. The planidia may transmit a bacteriosis. Pupal weight ( and ) decreased as number of pu/H increased. pupae were heavier than ones: 12.9 to 18.2 mg for against 9.7 to 12.5 mg for . Larval development lasted slightly longer for (8.7 d.) than for (8.3 d.), and its duration was little affected by superparasitism. 1, 2, 3 or 5 pl/H yielded 0.84–1.61–2.17 and 3.43 pu/H and 0.81–1.48–2.10 and 3.11 adults/H. An optimum was obtained with 3 planidia of L. diatraeae on G. mellonella or 1 to 2 to obtain heavier parasitoids.

     

Repeated larval diapause and diapause-free development in geographic strains of the burnet moth Zygaena trifolii Esp. (Insecta,Lepidoptera)

Summary Zygaena trifolii is a long-day insect with temperature-dependent photoperiodic responses. All larval instars are sensitive to photoperiod; however, diapause may occur at the third larval stage or any subsequent larval instars. There were quantitative differences within populations in the threshold photoperiod for diapause induction. The diapause response was polymorphic, so that larvae might enter diapause at different instars under the same culture conditions. Furthermore, decreasing photoperiods below a critical daylength shifted the diapausing instar towards earlier stages. Geographic strains of Z. trifolii showed discontinuous clinal variation. Near the northern edge of the distribution [Cologne (Köln), FRG], there is first an obligatory diapause, mainly during early instars, and additional facultative (repeat) diapauses during later larval instars in subsequent years. In the southern part of its distribution, this burnet moth is partially bivoltine in the field with a facultative first developmental arrest and a decreased capacity for repeated diapause (Valencia, Spain; Marseille, France). Further experiments indicated that the photoperiodically controlled diapause reaction is also influenced by the number of photoperiodic cycles experienced during the period spent in each larval instar, which depends on temperature. The adaptive significance of obligatory and facultative repeated diapause, varying even among the offspring of a single female, may be to buffer the populations against the more extreme and, from year to year, unpredictable fluctuations in climatic conditions at the northern edge of the distribution.Abbreviations L₃ feeding 3rd larval instar - L₄D diapausing 4th larval instar - L₅D2 repeat-diapausing larval instar with second diapause at the 5th larval stage - LD light-dark cycle - KT shortday conditions (e.g. LD 8:16) - LT long-day conditions (e.g. LD 16:8)     

Die Hypokotylfarbe als Markierungsfaktor von Genomstufen der Zuckerrübe

Zusammenfassung In zunehmendem Maße werden anisoploideBeta-Rübensorten angebaut, deren zytologische Kontrolle zwecks Feststellung der Genomstufenprozentanteile recht arbeitszeitaufwendig ist. Übereinstimmend mit polnischen Autoren wurde festgestellt, daß die Hypokotylfarbe ein geeigneter Markierungsfaktor für die einzelnen Genomstufen darstellt. Kreuzt man tetraploide Pflanzen, die ein grünes Hypokotyl besitzen, mit diploiden Pflanzen, die ein rosa Hypokotyl aufweisen, so erhält man von dem tetraploiden Partner tetraploide grüne und triploide hellbraune, von dem diploiden Partner diploide rosa und triploide hellbraune Nachkommenschaften. Die in bezug auf die Hypokotylfarbe heterozygoten Pflanzen kann man demnach von den homozygot grünen und homozygot rosa Individuen unterscheiden. Die Kreuzung diploid grünxtetraploid rosa ist für diese Zwecke nicht brauchbar, da sich die triploiden Heterozygoten mit einem grünen und zwei rosa Allelen in der Hypokotylfarbe nicht deutlich von den homozygoten rosa Pflanzen abheben. Auf die Bedeutung dieser Markierungsmöglichkeit für bestimmte Forschungsprobleme, die Züchtung und die Saatgutkontrolle wird hingewiesen.     

Regeneration of plantlets through organogenesis in the Himalayan yellow poppy,Meconopsis paniculata

Plantlet formation through organogenesis in callus cultures of Himalayan yellow poppy,Meconopsis paniculata D.Don (Prain), a threatened taxon of ornamental value, is described. Hypocotyl segments from 3-month-old laboratory-raised seedlings produced callus on agar-solidified Murashige and Skoog medium (MS) containing 10 M -naphthaleneacetic acid and 1 M kinetin. Shoots differentiated best from callus on MS containing 10 M indolebutyric acid (IBA) and 1 M 6-benzyladenine. The regenerated shoots rooted best on MS medium containing 10 M IBA. From seed germination to differentiation of plantlets through the two-step organogenesis process required 28–29 weeks.Abbreviations 2,4-d 2,4-dichlorophenoxyacetic acid - FAA formalin-acetic acid-alcohol - BA 6-benzyladenine - IAA indole-acetic acid - IBA indolebutyric acid - GA₃ gibberellic acid - NAA -naphthaleneacetic acid - RH relative humidity     

Histoenzymatic characterization of sub-types of Type I fibres in fast muscles of rats

Summary The histochemical activities of succinic dehydrogenase (SDH), myofibrillar Adenosine triphosphatase (ATPase) and alpha glycerophosphate dehydrogenase were studied in serial sections of rat vastus lateralis (red) (RVL), gastrocnemius and diaphragm muscles. Three main fibre-types were distinguished. The Type I fibres of RVL and gastrocnemius muscles fell into two distinct groups: one category-Type IA showed very low ATPase activity. The second category of Type IB fibres displayed moderate ATPase reaction. The Type IA fibres were divisible into two sub-groups when tested for SDH reaction. Type IA₁ fibres possessed a homogenous distribution of diformazan·granules throughout the fibre: Type IA₂ fibres displayed characteristic moth-eaten pattern of diformazan localization. The diaphragm muscle did not show either Type IB or Type IA₂ varieties. The great majority of Type I fibres were sub-type IA₁ in the three fast muscles studied. It is also demonstrated here that an inherent heterogeneity exists between Type I fibres of diaphragm and leg muscles in regard to -GPD localization. This histochemical data emphasizes the fact that subdivision of Type I striated muscle fibres of mammalian animals into two sub-types is only approximate and that a further subcategorization is possible.     

Genetic characterization of a new splice variant of the β2 subunit of the voltage-dependent calcium channel

This study reports a novel splice variant form of the voltage-dependent calcium channel ₂ subunit (_2g). This variant is composed of the conserved amino-terminal sequences of the _2a subunit, but lacks the -subunit interaction domain (BID), which is thought essential for interactions with the ₁ subunit. Gene structure analysis revealed that this gene was composed of 13 translated exons spread over 107 kb of the genome. The gene structure of the ₂ subunit was similar in exon-intron organization to the murine ₃ and human ₄ subunits. Electrophysiological evaluation revealed that _2a and _2g affected channel properties in different ways. The _2a subunit increased the peak amplitude, but failed to increase channel inactivation, while _2g had no significant effects on either the peak current amplitude or channel inactivation. Other subunits, such as ₃ and ₄, significantly increased the peak current and accelerated current inactivation.     

N6-(Δ2-Isopentenyl) adenine inhibits the alcohol dehydrogenase activity in cell-free extracts of Zymomonas mobilis

The plant growth substance N⁶-(²-isopentenyl) adenine (i⁶Ade) significantly inhibits the rates of ethanol oxidation and acetaldehyde reduction in vitro by cell-free extracts of Zymomonas mobilis and of an Escherichia coli recombinant strain, containing the Z. mobilis adhB gene. The two-substrate kinetics of ethanol oxidation (forward) is affected by increasing values of dissociation constants for coenzyme and coenzyme —enzyme complexes in the presence of i⁶Ade, whereas the reaction maximum velocity (V _m) remains unchanged and reflects the competitive type of inhibition. Changes of the kinetic constants of acetaldehyde reduction (back) are similar, except the increasing value of V _m and correspond to the CIS (competitive inhibition and stimulation) type of inhibition. The estimated values of inhibition constants of the forward and back reactions are 0.39 ± 0.05 mM and 0.19 ± 0.06 mM, respectively.     

Oxygen Consumption and Respiration Following Two Yoga Relaxation Techniques

The present study was conducted to evaluate a statement in ancient yoga texts that suggests that a combination of both calming and stimulating measures may be especially helpful in reaching a state of mental equilibrium. Two yoga practices, one combining calming and stimulating measures (cyclic meditation) and the other, a calming technique (shavasan), were compared. The oxygen consumption, breath rate, and breath volume of 40 male volunteers (group mean ± SD, 27.0 ± 5.7 years) were assessed before and after sessions of cyclic meditation (CM) and before and after sessions of shavasan (SH). The 2 sessions (CM, SH) were 1 day apart. Cyclic meditation includes the practice of yoga postures interspersed with periods of supine relaxation. During SH the subject lies in a supine position throughout the practice. There was a significant decrease in the amount of oxygen consumed and in breath rate and an increase in breath volume after both types of sessions (2-factor ANOVA, paired t test). However, the magnitude of change on all 3 measures was greater after CM: (1) Oxygen consumption decreased 32.1% after CM compared with 10.1% after SH; (2) breath rate decreased 18.0% after CM and 15.2% after SH; and (3) breath volume increased 28.8% after CM and 15.9% after SH. These results support the idea that a combination of yoga postures interspersed with relaxation reduces arousal more than relaxation alone does.     

Production of a novel syrup containing neofructo-oligosaccharides by the cells of Penicillium citrinum

A novel syrup containing neofructo-oligosaccharides was produced from sucrose (Brix 70) by whole cells of Penicillium citrinum. The efficiency of fructo-oligosaccharides production was more than 55% and those of the main carbohydrate components, 1-kestose (Fruf 21Fruf 21 Glc), nystose (Fruf 21Fruf 21 Fruf 21 Glc) and neokestose (Fruf 26 Glc12 Fruf), were 22, 14 and 11%, respectively.     

Comparative Modulation by 3α,5α and 3β,5β Neurosteroids of GABA Binding Sites During Avian Central Nervous System Development

Neurosteroids are endogenous Central Nervous System (CNS) compounds which act mainly by allosteric modulation of the GABA_A receptor complex. The presence of a 3-hydroxyl group and a 5-hydrogen atom have been found to be essential structural requirements for biological activity in mammals. In the present work we report the enhancing activity on [³H]GABA binding to its receptor sites in chick optic lobe produced by progesterone metabolites 3-hydroxy,5-pregnan-20-one (3,5-P) and 3-hydroxy,5-pregnan-20-one (3,5-P). Both steroids were found able to enhance [³H]GABA binding along ontogeny, displaying a similar profile at early developmental stages, while in adulthood 3,5-P had greater potency (EC₅₀ 0.22 M) and enhancing effect (E_max: 122%). In adult synaptic membranes, the two compounds displayed a complex interaction with the GABA_A receptor, disclosed by a Schild plot with slope below one and an incomplete displacement of 3,5-P by its 3,5 isomer. Such complexity could be related to the steroidogenic profile in avian CNS, with 5-reduced progesterone metabolites present since early development, while 3,5-P is found only in adulthood. Bearing in mind differences between avian and mammalian steroidogenic profiles and the relevance of 5-steroids in early avian development, we propose that 3,5-P, instead of the classical potent 3,5-steroids, may be the endogenous modulator of GABAergic activity in developing avian brain.     

Synergistic induction of cytotoxicity in macrophages by murine interferon-γ and biological response modifiers derived from microorganisms

Summary The ability of recombinant murine interferon-gamma (rMuIFN-) to activate murine macrophages with or without several biological response modifiers (BRM), including synthetic muramyl dipeptide derivatives (MDPs), was investigated. Mouse peritoneal macrophages were activated by rMuIFN- alone to the cytostatic state, but not the cytolytic state. Other BRM as well as bacterial lipopolysaccharide (LPS), including a lyophilized preparation of an attenuated strain of Streptococcus hemolyticus, a cell wall skeleton of bacillus Calmette-Guerin and synthetic MDPs, were highly active in generating the synergism with rMuIFN-. Macrophages were endowed with the cytolytic activities by combinations of rMuIFN- and MDP-Lys(L18); the combination of 100U/ml of rMuIFN- with 10 ng/ml of MDP-Lys(L18) was sufficient to induce cytolytic activities in macrophages. The synergism was observed when the macrophages primed with rMuIFN- were treated with LPS or MDP-Lys(L18), but not when the sequence of treatment was reversed. The cytotoxicity of macrophages induced by rMuIFN- with MDP-Lys(L18) was suppressed by priming with MDP-Lys(L18). The suppressive effect was also observed by priming with LPS in combinations of rMUIFN- and LPS. The reason for the suppression of macrophage activation by priming with LPS and MDP-Lys(L18) is at present unknown.     

Occurrence of airborne Cladosporium and Alternaria spores in Southern and Central Poland in 1995–1996

The concentration of airborne spores of Cladosporium and Alternaria has been investigated at five monitoring stations situated in cities from the foot of the Tatra Mountains to central Poland along a south-north transect (Zakopane, Kraków, Ostrowiec witokrzyski, Warszawa, Pozna) i.e. from a height of 900 m to 80 m above sea level. The aerobiological monitoring of fungal spores was performed by means of five Burkard volumetric spore traps.Cladosporium spores were dominant at all the stations. The highest Cladosporium and Alternaria spore concentrations were observed at all the sites in July and August, except at Warszawa in both years and at Pozna in 1995 where the maximum of Cladosporium spores occurred in June and July, and at Ostrowiec witokrzyski in 1995 where the maximum was found in July, August and September.Fungal spore concentrations in Zakopane and Kraków were significantly lower than those in Ostrowiec witokrzyski, Warszawa and Pozna and periods of abundant Cladosporium spore occurrence were different in these two groups of monitoring stations.     

Labor efficiency and intensity of land use in rice production: An example from Kalimantan

The Boserup hypothesis contends that land-intensive systems of agriculture will be adopted only when high population density precludes the use of land-extensive methods. In the Kerayan District of East Kalimantan (Indonesia) the Lun Dayeh practice permanent-field rice cultivation despite very low human densities. An examination of the relative labor efficiencies of shifting and permanent-field agriculture in the Kerayan, as well as of local environmental and historical variables, explains why this anomalous situation exists. It is argued that since relative success in production of rice by shifting- and permanent-field irrigated methods depends on many natural and social conditions other than levels of population density, the environment-free Boserup hypothesis cannot adequately explain or predict the occurrence of particular forms of rice agriculture.     

Die Richtungen des Nahrungsflusses im Darmtrakt der Kleinzikade Euscelidius variegatus KBM. (Jassidae)

Zusammenfassung Der Verlauf des Nahrungsflusses im Darmtrakt der Kleinzikade Euscelidius variegatus wird nach Verfütterung von farbstoffhaltiger Nährlösung ermittelt. Es wird der Beweis erbracht, daß die aufgenommene Nahrungsmenge in der Filterkammer geteilt wird und die beiden Anteile den Darmtrakt auf zwei verschiedenen Wegen in Richtung Rektalblase passieren. Ein Anteil der aufgenommenen Nährlösung wird über einen Kurzschlußweg in der Filterkammer sowohl über den Filterkammerdarm als auch über die Kryptonephridien direkt in den Enddarm gepumpt, während die in der Magentasche der Filterkammer verbleibenden Nahrungsanteile über einen langen Verdauungsweg zum After gelangen. Hierbei wird der Magentascheninhalt in den Magen gedrückt. Von dort aus passiert er den Mitteldarm und erreicht über den Enddarm den After. Der Kurzschlußweg und der Verdauungsweg können gleichzeitig benutzt werden. Der Kurzschlußweg wird von der Nahrung jedoch in viel kürzerer Zeit durchströmt als der längere Verdauungsweg.

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The directions of the flow of food in the alimentary trad of the leafhopper Euscelidius variegatus KBM. (Jassidae)

Summary The leafhopper Euscelidius variegatus is fed with synthetic food, coloured with 1% Azorubin-S. Its flow in the alimentary tract has been studied. It has been found that the sucked-in food is divided into two parts in the filter chamber, each taking different way in the alimentary tract for its flow. One part of the food is pumped into the hindgut via the short circuit way going through the filter chamber once over the Filterkammerdarm and also over the kryptonephries. That part of the food, which remains in the pocket of the filter chamber takes the long digestion way to the anus over stomach, midgut and hindgut. Both the ways could be used at the same time. But the food takes much shorter time for its passage through the short circuit way as compared to the time needed for the long digestion way.

     

The cytology of phytophthora infestans

Summary Phytophthora infestans has three kinds of somatic nuclei: an oval shaped nucleus (approx. 3.1×2.7 ) which stains diffusely except for a crescent shaped Feulgen positive cap which stains intensely; a granular nucleus whose contents are organized into a fairly constant number of stained bodies, and, a deeply staining condensed nucleus. The capped nucleus is thought to be metabolic or resting and the granular nucleus is thought to be dividing as it is most commonly found in hyphal tips. Attenuated forms of all three kinds of nuclei are found.Nuclear division is mitotic and intranuclear. Eight—ten chromosomes are seen at metaphase.Sporangia have a mean of 6.3 nuclei which is constant for age and strain of culture. Sporangia become multinucleate as a result of nuclear migration and not by division in the developing sporangium. Zoospores are usually uninucleate.The nuclear cap is persistent throughout nuclear division when it also divides. It is associated with flagella production and nuclear migration and has some of the properties of a blepharoplast.     

Variation of glucose 6-phosphate dehydrogenase in the HeLa and Detroit 98 cell lines and their clonal derivatives

Contrary to other reports, we have found that the A type G6PD found in two permanent cell lines—HeLa (Gey), with its single cell clonal derivative HeLa S3, and Detroit 98, with its four clonal derivative lines—is not a single variant but rather at least three different isozymes. One is heat stable with normal specific activity and normal A type electrophoretic migration, another is heat labile with normal specific activity and normal A type electrophoretic migration, and the third is heat labile with reduced specific activity and slightly slow A type electrophoretic migration. We also found that in a mosaic cell population with respect to G6PD phenotype, the predominant G6PD phenotype varied randomly over a 5-month period, that the G6PD phenotype might be mutable in permanent cell lines, and that spontaneous human cell lines might not be HeLa cell contaminants as has been suggested.Aided by the National Institutes of Health General Research Support Grant # 5 S01 FR05507.     

Ultrastructure of four types of striated muscle fibers in the atlantic hagfish (Myxine glutinosa,L.)

Summary Four types of striated muscle fibers with distinctive ultrastructure were defined in the Atlantic hagfish (Myxine glutinosa, L.): white, intermediate, and red fibers of m. parietalis, and red fibers of m. craniovelaris.White fibers are thick, contain very few mitochondria and fat vacuoles, and possess distinct and separate myofibrils with thin Z-disks and distinct M-lines. Intermediate fibers are thinner, possess largely similar myofibrils that often are even better separated due to a higher content of fat vacuoles and especially mitochondria and glycogen granules. Red fibers of m. parietalis contain large amounts of mitochondria, fat vacuoles, and glycogen granules. Their myofibrils possess M-lines, and although branching more, the myofibrils of red fibers conform with a Fibrillenstruktur pattern like those of white and intermediate fibers. Red fibers of m. craniovelaris are very thin, possess many smaller fat vacuoles, and large amounts of mitochondria and glycogen granules. The myofibrils are significantly thinner than in m. parietalis fibers, run as quite independent well separated units, possess thicker Z-disks, and lack M-lines. Large amounts of myosatellite cells are associated with these red fibers.Triads are located near A/I-junctions in all four fiber types and occur irregularly, the density of triads being different in the various fiber types.We are indebted to Dr. Finn Walvig, Biological Station, University of Oslo, Drøbak, for supply of hagfishes, and we also wish to thank Dr. Jan K. S. Jansen, Institute of Physiology, University of Oslo, for valuable suggestions during this study.