Über die Zytologie der Parthenogenese und der Geschlechtsbestimmung bei der GallmückeOligarces paradoxus Mein

Summary InOligarces paradoxus, the chromosomal behaviour was compared during pedogenetic development of and . The -egg undergoes a single non-reductional maturation division, the -egg shows two divisions which result in reduced nuclei. After maturation in the -egg, the number of chromosomes is restored by endomitosis. The nuclei of germ-line cells contain a high number of chromosomes (: 74\2-82; : at least 58) in both sexes. In somatic nuclei, the number is diminished by elimination to 10 in , to 5 in .     

Cytogénétique desLeggada: (1) La formule chromosomique deMus (Leggada)bufo Th., (2) Nouvelles données sur la délétion portant sur le bras court d'unX chezMus (Leggada)triton Th

Summary The author treats 2 topics connected with his studies on the cytogenetics of the African pigmy-mice. (1)Mus (Leggada) bufo Th. shows the primitive complement already detected in other species or subspecies (minutoides ssp ₁,indutus, tenellus, setulosus): 2N=36,N.F.=36, sex chromosomesPR. (2) The deletion of the short arm of oneX-chromosome (X _dc ) was previously observed as heterozygous mutation by 4 in a sample of 7 and 5 . A more important sample (18 , 21 ) gives the following results: 11 X-X, 10 X-X _dc , 18 X-Y. The occurrence of X _dc -X _dc and of X _dc -Y is also very improbable. It is not easy to understand how the chromosomeX _dc may persist in the population if the complementsX _dc -X _dc andX _dc -Y are lethal, which seems to result from these observations.     

Further morphological and biochemical studies on normal and hybrid embryos of sea urchins

Zusammenfassung (1) Es wurde bei den SeeigelartenParacentrotus ,Arbacia undSphaerechinus sowie den drei BastardenPar ×Arb ,Arb ×Par undPar ×Sphaer für eine Reihe von Entwicklungsstadien die Anzahl der Kerne pro Keim bestimmt (Tabelle). Der morphogenetischen Hemmung der Bastarde entsprechen herabgesetzte Kernzahlen und parallel eine Herabsetzung der DNS-Synthese. (2) Es wurde bei den genannten reinen Arten und den Bastarden derUmsatz der RNS bestimmt. Er geht in allen Fällen, bei den reinen Arten wie bei den Bastarden, der DNS- Synthese parallel.

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Our work was supported by a grant from the Schweizerischer Nationalfonds zur Förderung der wissenschaftlichen Forschung. We express our sincere thanks to the Nationalfonds and also to the authorities at the Zoological Station at Naples for generous help and supply of materials and facilities. — This paper is thankfully dedicated byF. Baltzer toF. E. Lehmann for his kind hospitality in the Bernese Institute.     

Funktion der Spermien in inkompatiblen Kreuzungen der StechmückeCulex pipiens L.

Summary After irradiating males of the incompatible crossC. pipiens Hamburg ×C. pipiens Paris with X-ray doses between 1 kR and 40 kR, it could be shown that in this cross the sperm has only the function of activating the egg. All the hybrid embryos develop from the haploid female pronucleus.Herrn Professor Dr.H. Laven danke ich für Unterstützung und wertvolle Diskussionen.     

Determination of reproductive categories in the life cycle of aphids

Riassunto L'incrocio fra di ceppi diB. brassicae con scarsa tendenza alla partenogenesi, con anfigoniche di ceppi tendenti alla partenogenesi costante, ha dato alla F₁ percentuali di sessuali intermedie rispetto a quelle dei ceppi usati per l'incrocio. Le categorie riproduttive degli Afidi sembrano quindi determinate da poligeni.     

Unkreaktion mit Befreiungsruf beim Weibchen der KreuzkröteBufo calamita

Summary The release call which is uttered by Bufo in connection with specific movements can also be evoked in the ofBufo calamita. This is indicative of homology of the male release call and the usually silent release movements of the .

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Mit Unterstützung des Schweizerischen Nationalfonds zur Förderung der wissenschaftlichen Forschung.     

Sex-specific pheromones in a termite

Résumé La glande sternale des jeunes imagos et secrète une phéromone attractive pour les individus du sexe opposé. Les peuvent prendre une position d'appel indentique à celle connue des . Les imagos, mais pas les nymphes, reconnaissent les phéromones sexuelles de la phéromone de piste sécrétée par la glande sternale des nymphes.     

Chromosomal polymorphism in the guinea-pig,Cavia porcellus

Zusammenfassung Bei der karyologischen Analyse von Metaphasen in Knochenmark, Cornea und andern Geweben des indischen Meerschweinchens,Cavia porcellus (7 , 3 ) wurde festgestellt, dass drei männliche Individuen in einem autosomalen Chromosom heterozygot waren. Das Chromosom wird als Marker III bezeichnet.     

Extreme chromosomal polymorphism in a coccinellid beetle

Zusammenfassung Von drei vonChilocorus stigma wies ein Tier eine (A), eines zwei (A, B) und das dritte drei (A, B, C) zentrische Fusionen auf; 2n war 26, 25 und 24. Beim mit 2n = 24 sind mindestens zwei Bivalente heterozygot. Abgesehen vom Unterschied der Geschlechtschromosomen (XX: XO) sind daher 243 verschiedene chromosomale Typen möglich. 2n wird von 21 () zu 28 () variieren. Weitere Fusionen bei den Chromosomen der heterozygoten Paare würden zu 2n = 19 führen, während sich nach andern Fusions-Kombinationen Ringkomplexe bilden müssten.     

Synthesis and pharmacological properties of [1-N4-dimethyl-asparagine]-angiotensin II

Summary [1-N⁴-Dimethyl-asparagine]-angiotensin II was synthesized by Merrifield's solid-phase procedure. The analogue gave rat blood pressure about 70% relative potency to Hypertensin (Ciba). Rabbit aorta strips gave intrinsic activity _E=1, a PD₂ of 6.92±0.09 and an affinity relative to [Asn¹]-angiotensin II of 6.5%.The editors do not hold themselves responsible for the opinions expressed in the authors' brief reports. — Les auteurs sont seuls responsables des opinions exprimées dans ces brèves communications. — Für die Kurzmitteilungen ist ausschliesslich der Autor verantwortlich. — Per le brevi comunicazioni è responsabile solo l'autore. — . — Solo los autores son responsables de las opiniones expresadas en estas comunicationes breves.Acknowledgment. The authors wish to express their appreciation to Dr Emanuel Escher, School of Medicine, Centre Hospitalier Universitaire, Sherbrooke, Quebec, for his help in providing the biological data and critical comments.     

W chromosome in the Indian water snake (checkered keel back)Natrix piscator (colubridae)

Zusammenfassung Die diploide Chromosomenzahl beider Geschlechter beträgt 40: 10 Macrochromosomen und 30 Microchromosomen. Die GeschlechtschromosomenZZ () undZW () sind cytologisch erkennbar.     

Durch polarisiertes Licht hervorgerufene Optomotorik beiUca tangeri

Summary Optomotor reactions were tested in 10Uca tangeri (5, 5) of intermediate body size, by slowly rotating the plane of polarized light entering the apical ommatidia of the animal; 8 out of 10 animals showed definite optomotor reactions immediately at, or a short time after, the beginning of the rotation. There were no such reactions when the apical ommatidia were stimulated by a rotating black and white disc.     

A study of DNA synthesis in sea urchin hybrids by the incorporation of H3-thymidine

Zusammenfassung (1) Es wird die DNS-Synthese der letalen SeeigelbastardeParacentrotus ×Arbacia (PA) undParacentrotus ×Sphaerechinus (PS) mit H³-Thymidin untersucht. (2) Dem verschiedenen, der Letalität vorausgehenden Entwicklungstpus (PA ohne, PS mit Chromosomenelimination) entspricht ein verschiedener Verlauf der Hemmung der DNS-Synthese. Parallel dazu wird die Vermehrung in der Anzahl der Kerne verglichen.     

Study of neurosecretory cells ofHelix pomatia by intracellular dye injection

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Molecular ontogenesis and molecular genetics in the crosses of toads

Riassunto È stata studiata la comparsa di antigeni nel corso dello sviluppo di due specie di rospi:Bufo bufo eB. viridis e dei loro incroci reciproci. Alcuni antigeni al loro primo apparire precipitano solo con l'antisiero specie-specifico e, solo dopo lo stadio di bottone caudale, sono precipitati anche dall'antisiero dell'altra specie; questo viene interpretato quale una ontogenesi molecolare. Negli incroci, le molecole con gruppi reattivi per i due antisieri sono più frequenti nell'incrocio vitale (B. bufo ×B. viridis ), mentre l'incrocio letale (B. viridis ×B. bufo ) mostra alcuni antigeni separati che precipitano ognuno con un antisiero.

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This investigation was supported by a grant from the Consiglio Nazionale delle Richerche.     

Influence de l'aneuploïdie sur la différenciation protéique au cours du développement embryonnaire de l'UrodèlePleurodeles waltlii Michah

Summary No qualitative differences have been found between the electrophoretic protein patterns observed in normal and in aneuploid embryos ( 3n × 2n). The overall amount of extractable protein increases, however, less rapidly in aneuploid than in normal embryos.     

Nouvelles contributions à la cytogénétique desMus Africains du sous-genreLeggada

Summary The author describes four new chromosome complements in the African pigmy-mice (Mus, subgenusLeggada). (1) One form from Angola has 18 metacentric chromosomes (N.F.=36) in both sexes. In contrast toMus minutoïdes minutoïdes Smith from South Africa, whose females have the same chromosome complement while the males show an acrocentric and shortY-chromosome, we have here a metacentricY. It is a confirmation of the hypothesis that theY ofM. m. minutoïdes was primarily of translocated type (TR) but lost a big intercalary segment of the autosomic arm. (2) In another species from Angola 2N=34;N.F.=36. It is the first case in the subgenus where a Robertsonian fusion occurs between autosomes before the transformation of the sex-chromosomesPR into sex-chromosomesTR. This observation is a confirmation that the complement 2N=36;N.F.=36 is the primitive one, being found in the three groups of species,minutoïdes, bufo-triton andtenellus. (3) Indeed, from Ghana, I have got specimens ofM. tenellus. We have here to deal with the primitive chromosome complement: 2N=36;N.F.=36. (4) In a sample of 12Leggada from the region of Bukawu (Congo), there are 5 and 7 . 4 show a total deletion of the short arm of theX-chromosome. In spite of the absence of X _dc -Y and of X _dc -X _dc in the sample, it is probable that neither of these complements is lethal.     

Bovine microvascular endothelial cells of separate morphology differ in growth and response to the action of interferon-γ

Five cell types recently isolated from the bovine corpus luteum differed in their epithelioid morphology and their cytoskeleton, but shared common criteria of microvascular endothelial cells^1,2. To give strong evidence for the separate entity, the growth rate of the 5 phenotypically different cells was studied. They were seeded at low density on day 0. Most of these cells were treated with 200 to 1000 U recombinant bovine interferon- (IFN-) for 3 days. The untreated remainder served as controls. Cell counts were made for all cultures on days 4, 7, 10 and 13. morphology: 13 d after treatment with IFN- senescent cells as well as intact cells occurred in cultures of cell types 1 to 4. Cultures of cell type 5 were apparently unchanged and resembled their untreated counterparts. Desminpositive cells in cultures of cell type 2 developed cell processes. Growth rate: In the absence of IFN-, the growth rate was high for cell types 3 and 4, moderate for cell type 1, and low for cell types 2 and 5. The presence of IFN- caused anti-proliferative effects. These were higher for cell types 3 and 4 than for cell types 1 and 2. IFN- could be cytotoxic on cell type 3. In contrast, the cytokine tended to support the cell growth of cell type 5. These findings substantiate the postulate that endothelial cells exhibiting separate morphology in culture also function differently.     

Artificial triploid hybrids by interspecific mating ofOdontophrynus (Amphibia,anura)

Résumé Des hybrides triploïdes ont été obtenus par croisement deOdontophrynus cultripes, amphibien diploïde, avecO. americanus, tétraploide. Les hybrides interspécifiques présentent normalement 33 chromosomes dans les cellules somatiques. Les hybridesO. cultripes ×O. americanus sont plus viables que lesO. americanus ×O. cultripes .

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This work was supported by Public Health Service Research Grant No. GM-14577-02 from the National Institute of General Medical Sciences and by Fundo de Pesquisas do Instituto Butantan.     

Hormone dependency of sex-linked feathering of female hybrid chick embryos (cross new Hampshire ♂ × light sussex ♀)

Zusammenfassung Die rote Daunenpigmentierung der weiblichen F₁ Hybriden der Hühnerrassen Cross New Hampshire × Light Sussex entsteht nicht ohne Ovarialhormone, wie Kastrationsexperimente beweisen. Sie kommt aber zustande, wenn man ganz oder subtotal kastrierten Embryonen Östrogene oder Androgene zuführt oder embryonale Keimdrüsen implantiert.