Tn402: a new transposable element determining trimethoprim resistance that inserts in bacteriophage lambda.

We have found that the trimethoprim resistance determinant of the IncP plasmid R751 (Jacob et al., 1977; Jobanputra and Datta, 1974) transposes to bacteriophage lambda. We call this transposable element Tn402.     

Diaphragmatic defects in children of consanguineous parents

Summary It is known from the literature that total loss of the short arm causes complete Turner's signs (Hoo, 1975; Therman and Patau, 1974). Partial deletions of the short arm of the X chromosome are in some cases compatible with fertility (Fraccaro et al., 1977; Hoo, 1979), but in other cases they cause a significant ovarial insufficiency with Turner's signs (Giraud et al., 1974) or gonadal dysgenesis (Petrinelli et al., 1978). A common sign for all the patients having the Xp-wwith the break point in the dark band (p113-p21) seems to be a short stature. The presence of other clinical signs is rather irregular. In this work, a 25-year-old female patient having a Xp deficiency in region p21 (46,X,del(X) (qterp21:)) with short stature, primary amenorrhea, sterility, and clear Turner's is described.     

华南浅海相泥盆系吉维特阶和弗拉阶四射珊瑚组合特征

中泥盆世吉维特晚期(更精确的说是在中吉维特期末)发生的生物更替事件使大量的头贝、全部的泡沫珊瑚亚目以及大多数的绳珊瑚科和内板珊瑚科惨遭灭绝。晚泥盆世弗拉期出现了许多新生分子,诸如Micto-phyllum,Wapitiphyllum,Pseudozaphrentis,Peneckiella等。根据珊瑚的不同组合特征可以鉴别出它们的地质时代。华南自上而下可划分出4个四射珊瑚组合,分别为上泥盆统弗拉阶(Frasnian):4)Disphyllum-Wapitiphyl-lum组合(牙形类gigas或rhenana带和hassi-jamieae带),3)Mictophyllum-Pseudozaphrentis组合(牙形类asymmetricus带);中泥盆统吉维特阶(Givetian):2)Endophyllum-Sunophyllum组合(牙形类varcus带的中部和下部之上段),1)Stringophyllum-Paramixogonaria组合(牙形类hemiansatus带-varcus带最下部)。     

Map arrangement of the SLA chromosomal region and the J and C blood group loci in the pig

Linkage studies of three-point crosses (triple backcross matings) showed that the linear sequence of three of the pig's immunogenetic traits — the SLA major histocompatibility complex and the J and C blood group loci — is SLA-J-C . Andresen & Baker (1964) and Rasmusen (1965) described close linkage between the J and C blood group loci and respectively found their recombination frequency to be 5.29 ± 1.1 % and 7.00 ± 3.4 %; by combining the data the exact frequency was determined at 5.75 ± 0.79 % (Muir & Rasmusen, 1974). Later, linkage of the SLA major histocompatibility complex with both J (Hruban et al., 1976) and C (Hruban et al., 1977) erythrocytic loci was found. The maximum tabular lod score values were found in the recombination fraction Θ= 0.10 in comparison of SLA and J and in the fraction Θ= 0.20 in comparison of SLA and C (Hruban et al., 1977).     

Antipain microinjection prevents progesterone to inhibit adenyl cyclase in Xenopus oocytes

Microinjection of antipain, an inhibitor of thiol and Ca2+-dependent proteases, in immature Xenopus oocytes inhibited meiotic maturation induced by progesterone, but not by transfer of cytoplasm taken from maturing oocytes. Oocytes could be released from antipain inhibition by increasing progesterone concentration. alpha-32P-ATP was microinjected to study adenylcyclase in ovo. As already reported, neosynthesis of cAMP was decreased following progesterone application. This decrease was not observed, or it was considerably reduced, in oocytes previously injected with antipain. In amphibian, full-grown ovarian oocytes are arrested at first meiotic prophase, and have a large nucleus known as the germinal vesicle. Progesterone induces the production of a cytoplasmic maturation-promoting factor (MPF), which itself triggers germinal vesicle breakdown (GVBD), and subsequent events of meiotic maturation (Masui and Markert, 1971; Gerhart et al., 1984). A considerable body of evidences support the view that release from prophase block is due to inactivation of a cAMP-dependent protein kinase (reviewed by Maller, 1983). On the other hand, progesterone has been shown to induce a transient decrease in cAMP level (Speaker and Butcher, 1977; Schorderet-Slatkine et al., 1982; Cicirelli et al., 1985), and this initial drop of cAMP, along with a number of studies indicating a decrease in adenylate cyclase activity (Mulner et al., 1979; Baltus et al., 1981; Sadler and Maller, 1981; Finidori-Lepicard et al., 1981; Jordana et al., 1981), provided key support to the theory that an early drop in cAMP led to the dephosphorylation of a hypothetical protein which initiates maturation.(ABSTRACT TRUNCATED AT 250 WORDS)     

峡东地区早寒武世水井沱组古盘虫类三叶虫的再研究

对峡东和邻近地区早寒武世古盘虫类三叶虫的再研究,支持将Emeidiscus Li,1980;Mianxrindiscus S．Zhang et Zhu in Zhang et al,1980;Mianxiandiscus(Liangshandiscus)S．Zhang in Zhang et al．,1980;Hupeidiscus Chang in Lu et al．,1974;Guizhoudiscus S．Zhang in Zhang et al．,1980;Shizhudiscus S．Zhang et Zhu in Zhang et al．,1980等属作为Tsunyidiscus Chang,1966的同义名的意见。并对前人所建立的有关属的种,进行了重新研究和整理,作了大量的归并和修订。就目前所知道,峡东地区早寒武世水井沱组的古盘虫类三叶虫仅有Tsunyidiscus Chang,1966和Sinodiscus Chang in Lu et al,1974两属。Hupeidiscus经修订归入Tsunyidiscus Chang,1966后,原Hebediscus orientalis Chang,1953(即原Hupeidiscus的模式种)一种的种名与Tsunyidiscus orientalis(Walcott,1905)重名,故将前者重新命名为Tsunyidiscus pertenus nom．nov．。文中还记述了湖北宜昌、秭归等地的早寒武世古盘虫类三叶虫2属3种,包括Tsunyidiscus yanjiazhaiensis S．Zhang,Zhou et Yuan in Yin and Li,1978;Tsunyidisacutus(Sun,1983);Sinodiscus changyangensis S．Zhang in Zhou et al．,1977。     

Isolation of a D-genome specific repeated DNA sequence fromAegilops squarrosa

Three repeated sequence clones, pAS1(1.0 Kb), pAS2(1.8 Kb) and pAS12(2.5 Kb), were isolated fromAegilops squarrosa (Triticum tauschii). The inserts of the three clones did not hybridize to each other. Two of the clones, pAS2 and pAS12, contain repeated sequences which were distributed throughout the genome. The clone pAS1 sequence was more restricted and was located in specific areas on telomeres and certain interstitial sites along the chromosome length. This cloned sequence was also found to be restricted to the D genome at the level ofin situ hybridization. The pAS1 sequence will be useful in chromosomal identification and phylogenetic analysis. All three clones will allow assessment of genome plasticity inAegilops squarrosa. Nuclear DNA content varies over a range of 10,000 fold among all organisms (Nagl et al., 1983). Among angiosperms, at least a 65-fold range in genome size occurs in diploid species (Sparrow, Price and Underbrink, 1972; Bennett, Smith and Heslop-Harrison, 1982). This DNA variation has been reported within families, genera, and species (Rothfels et al., 1966; Rees and Jones, 1967; Miksche, 1968; Price, Chambers and Bachmann, 1981). Much of the interspecific variation in genome size among angiosperms appears to be due to amplification and/or deletion of DNA within chromosomes. The variation in genome size does not appear to result in changes in the number of coding genes (Nagl et al., 1983). While the number of coding genes, with the exception of rDNA in specific examples, appears to remain constant, the remaining non-coding regions are quite flexible. This non-coding DNA encompasses over 99% of the plant genome and consists of sequences that exist as multiple copies throughout the genome and are identified as repeated DNA sequences (Flavell et al., 1974). Flavell et al. (1974) have reported that increasing genome size in higher plants is associated with increasing repetitive DNA amounts. Subsequent reports have substantiated this correlation (Bachmann and Price, 1977; Narayan, 1982). In various cereals, heterochromatin, which has been demonstrated to be correlated with the location of specific repeated DNA sequences, has been positively correlated with genome size (Bennett, Gustafson and Smith, 1977; Rayburn et al., 1985). Furuta, Nishikawa and Makino (1975) found significant DNA content variation among different accessions ofAegilops squarrosa L. This species contains the D genome, a pivotal genome in several polyploid species and also found in hexaploid wheat (AABBDD). The importance of this genome to the study of bread wheat genomes makes the mechanism(s) of this genomic plasticity of particular interest. In order to determine which sequences are varying, one must first have a way to identify specific types of chromatin and/or DNA. Specific types of chromosome banding such as C- and N-banding have been used to identity types of chromatin in previous studies. C-banding of the D genome results in very lightly staining bands whose pattern is somewhat indistinct. N-banding alternatively has been shown to be useful in identifying certain chromosomes of hexaploid wheat but is limited by the lack of major bands in the D genome (Endo and Gill, 1984). Specific DNA sequences have been isolated fromTriticum aestivum cultivar “Chinese Spring” (hexaploid wheat). However, these sequences are representatives of the A and/or B genomes of hexaploid wheat and are not found in significant quantities in the D genome (Hutchinson and Lonsdale, 1982). Various other repeated DNA sequences have been successfully isolated from rye (Bedbrook et al., 1980) and identified on rye chromosomes (Appels et al., 1981; Jones and Flavell, 1982). Certain of these sequences are found in wheat genomes, but the sequences are representative of only a minor fraction of the D genome (Bedbrook et al., 1980; Rayburn and Gill, 1985). The purpose of this report is to describe three distinct repeated DNA sequences isolated fromA. squarrosa (D genome). Two clones appear to be distributed throughout the total genome, and the third clone is restricted to specific sites along the chromosomes. This latter clone will prove useful in cytologically defining the D genome chromosomes. These sequences appear representative of two types of repeated DNA genome organization: 1) sequences distributed throughout the genome and 2) specific arrays of repeated sequences. The availability of such repeated DNA sequence clones along with the known intraspecific DNA content variation inA. squarrosa will allow the study of genomic plasticity of this species.     

Two coupled oscillators as a model for the coordinated finger tapping by both hands

Recently, it was found that rhythmic movements (e.g. locomotion, swimmeret beating) are controlled by mutually coupled endogeneous neural oscillators (Kennedy and Davis, 1977; Pearson and Iles, 1973; Stein, 1974; Shik and Orlovsky, 1976; Grillner and Zangger, 1979). Meanwhile, it has been found out that the phase resetting experiment is useful to investigate the interaction of neural oscillators (Perkel et al., 1963; Stein, 1974). In the preceding paper (Yamanishi et al., 1979), we studied the functional interaction between the neural oscillator which is assumed to control finger tapping and the neural networks which control some tasks. The tasks were imposed on the subject as the perturbation of the phase resetting experiment. In this paper, we investigate the control mechanism of the coordinated finger tapping by both hands. First, the subjects were instructed to coordinate the finger tapping by both hands so as to keep the phase difference between two hands constant. The performance was evaluated by a systematic error and a standard deviation of phase differences. Second, we propose two coupled neural oscillators as a model for the coordinated finger tapping. Dynamical behavior of the model system is analyzed by using phase transition curves which were measured on one hand finger tapping in the previous experiment (Yamanishi et al., 1979). Prediction by the model is in good agreement with the results of the experiments. Therefore, it is suggested that the neural mechanism which controls the coordinated finger tapping may be composed of a coupled system of two neural oscillators each of which controls the right and the left finger tapping respectively.     

Giemsa banding patterns in chronic lymphocytic leukaemia.

The banding patterns of chromosomes from 20 patients with chronic lymphocytic leukaemia (C.L.L.) have been analyzed. 97 of 100 metaphases examined had a normal banding pattern. The 3 remaining metaphases, all from one patient had bands similar to those seen after aging. It is concluded that the chromosomes in C.L.L. have normal banding patterns. The majority of cytogenetic studies in chronic lymphocytic leukaemia have reported normal chromosomes (Fitzgerald and Adams 1965; Oppenheim et al., 1965; Lawler et al., 1968). An inherited abnormality of G group chromosome (No. 22) has been reported in a family, three members of whom developed C.L.L. (Fitzgerald and Hamer, 1969), but further investigations of cases of familial leukaemia failed to reveal a similar abnormality (Fitzgerald et. al., 1966). The development of new techniques which allow the positive identification of individual chromosomes (Caspersson et al., 1969; Dutrillaux and Lejeune, 1971; Sumner et al., 1971; Seabright, 1971), has revolutionised human cutogenetics and revealed additional information regarding chromosome abnormalities and leukaemia (Rowley, 1973; Lobb et al., 1972; Milligan and Garson, 1974). The purpose of this investigation was to determine whether the chromosomes in C.L.L. have normal banding patterns.     

Production of presumptive humoral haematopoietic regulators in canine cyclic haematopoiesis

Abstract. Conditioned media (CM) were prepared according to previously published techniques from the bone marrow of dogs with cyclic haematopoiesis (CH). CM prepared from day 9 marrows inhibited mouse bone marrow CFU-s proliferation rate while CM from day 10 marrows were stimulatory and also contained an erythroid stimulating factor which appeared to be erythropoietin. In addition a highly significant trend from CM containing CFU-s inhibitory materials to media with CFU-s stimulatory activity was observed through cycles day 1 to 8. These studies further support the concept that CH is due to a defect in factors controlling stem cell proliferation and suggest that a major event occurs in CH dog marrow on days 9 and/or 10 of the cycle. Bone marrow transplantation studies (Dale & Graw, 1974; Weiden et al., 1974; Jones et al., 1975b) have indicated that canine cyclic haematopoiesis (CH) is probably due to a disorder in the multipotential stem cells. Morphological evidence (Scott et al., 1973) and the almost synchronous cycling of CFU-e, CFU-c and diffusion chamber progenitor cells (DCPC) (DUM et al., 1977, 1978a, b) lend support to such a theory. However, efforts to identify the mechanisms controlliig multipotential stem cell proliferation in dogs have been handicapped by the lack of suitable techniques to study these cells in the canine. Recently, Wright and co-workers (Wright & Lord, 1978, 1979; Wright et al., 1979; Lord et al., 1979), on the basis of previous observations (Frindel et al., 1976; Frindel & Guigon, 1977), described the preparation of species non-specific, bone marrow conditioned media (CM) which are capable of influencing the proliferation rate of murine colony forming units-spleen (CFU-s). The studies now reported were designed to determine if CM prepared from canine CH marrow would influence the proliferation rate of murine bone marrow CFU-s. The results indicate that a major event, possibly related to the in vivo control of stem cell proliferation in dogs with CH, occurs on days 9–10 of the cycle; day 1 being the first day when the peripheral blood neutrophil count falls below-1600 mm³.     

北祁连山东段早石炭世棘鱼类、辐鳍鱼类和软骨鱼类--北祁连山东段石炭纪鱼类序列研究之一

对甘肃靖远一带和内蒙古自治区黑山地区早石炭世前黑山组、臭牛沟组和靖远组中三亚纲鱼类微体化石进行了形态学和古组织学研究。这些化石涉及 7个目或亚目 ,含 4属 4种 ,其中有 2新种。文中记述的属均为全球广布的属。建立了 3个早石炭世鱼类组合 ,这是我国早石炭世第一个鱼类组合序列。辐鳍鱼类和软骨鱼类中 2个目的化石均为我国早石炭世鱼类的首次记录     

A protein secondary structure prediction scheme for the IBM PC and compatibles

A prediction scheme has been developed for the IBM PC and compatiblescontaining computer programs which make use of the protein secondarystructure prediction algorithms of Nagano (1977a,b), Gamieret al. (1978), Burgess et al. (1974), Chou and Fasman (1974a,b),him (1974) and Dufton and Hider (1977). The results of the individualprediction methods are combined as described by Hamodrakas etal. (1982) by the program PLOTPROG to produce joint predictionhistograms for a protein, for three types of secondary structure:-helix, ß-sheet and ß-turns. The schemerequires uniform input for the prediction programs, producedby any word processor, spreadsheet, editor or database programand produces uniform output on a printer, a graphics screenor a file. The scheme is independent of any additional softwareand runs under DOS 2.0 or later releases. Received on January 26, 1988; accepted on May 24, 1988     

Standardization of procedures for nitrogen fractionation of ruminant feeds

The Cornell Net Carbohydrate Protein Model (Chalupa et al., 1991; Sniffen et al., 1992) has developed the need for uniform procedures to partition feed nitrogen into A, B, and C fractions (Pichard and Van Soest, 1977). While carbohydrate fractions are relatively standardized (based on NDF, ADF with corrections for ash, protein, and lignin), the fractionation of plant nitrogen has been open to considerable variation in procedures. This has led to non-uniformity among reported values for nitrogen fractions. This paper recommends reliable procedures for nonprotein nitrogen (NPN) and buffer-soluble protein. These procedures have been examined for reproducibility and relevance to biological expectations. Procedures for acid-detergent insoluble nitrogen (ADIN), and neutral-detergent insoluble nitrogen (NDIN) are also included as they are required for the model. Some alternatives in certain procedures are offered.     

Reduced Somatostatin in Hypothalamus of Young Male Mouse Increases Local but not Circulatory GH

The release of growth hormone (GH) from the pituitary gland is primarily inhibited by somatostatin (SRIF) from the hypothalamus via interactions with five types of SRIF receptors (SSTRs). However, the inhibition mechanism of SRIF on GH has not been fully examined. In this study, we repressed the hypothalamic SRIF in young male mice by stereotaxic injection of the lentiviral-shRNA against SRIF to investigate the role of hypothalamic SRIF on hormone secretion in the GH/IGF-1 axis. We found that the reduction of SRIF in hypothalamus was associated with an increase in the protein, but not the mRNA level, of the GH in the pituitary where SSTR 2 and SSTR 5 act importantly. Interestingly, the level of blood circulatory SRIF, GH, IGF-1 and the body weight were not significantly influenced by the downregulation of hypothalamic SRIF. Our findings provide insights into the mechanisms underlying the inhibition of SRIF on GH secretion.     

Types of enzymatic overdosing in trisomy 21: erythrocytic superoxide dismutase-AJ and phosphoglucomutase.

A comparative study was carried out on the hemolysates of 6 trisomic 21 and 6 normal subjects, by electrophoresis in starch gel, determining by a combined staining method both SOD-A (former IPO-dimer) and PGM activity. The enzymes were found statistically to be in a hyperactive status, the ratio of trisomic to normal values being approximately equalt to 1.4. SOD-A supraactivation is the effect of a genic dose, as demonstrated in earlier works (Sichitiu, 1973; Sichitiu et al., 1974; Sinet et al., 1974), whereas PGM hyperactivity appears to be modified secondarily, the same as the activity of other cellular enzymes in Down's disease.     

Genetic localization of diuron- and mucidin-resistant mutants relative to a group of loci of the mitochondrial DNA controlling coenzyme QH2-cytochrome c reductase in Saccharomyces cerevisiae.

Summary Diuron-resistance, DIU (Colson et al., 1977), antimycin-resistance, ANA (Michaelis, 1976; Burger et al., 1976), funiculosin-resistance, FUN (Pratje and Michaelis, 1977; Burger et al., 1977) and mucidin-resistance, MUC (Subik et al., 1977) are each coded by a pair of genetic loci on the mit DNA of S. cerevisiae. In the present paper, these respiratory-competent, drug-resistant loci are localized relative to respiratory-deficient BOX mutants deficient in coenzyme QH₂-cytochrome c reductase (Kotylak and Slonimski, 1976, 1977) using deletion and recombination mapping. Three drug-resistant loci possessing distinct mutated allelic forms are distinguished. DIU1 is allelic or closely linked to ANA2, FUN1 and BOX1; DIU2 is allelic or closely linked to ANA1, MUC1 and BOX4/5; MUC2 is allelic to BOX6. The high recombinant frequencies observed between the three loci (13% on the average for 33 various combinations analyzed) suggest the existence of either three genes coding for three distinct polypeptides or of a single gene coding for a single polypeptide but subdivided into three easily separable segments. The resistance of the respiratory-chain observed in vitro in the drug-resistant mutants and the allelism relationships between respiratory-competent, drug-resistant loci and coQH₂-cyt c reductase deficient, BOX, loci strongly suggest that each of the three drug-resistant loci codes for a structural gene-product which is essential for the normal coQH₂-cyt c reductase activity and is obviously a good candidate for a gene product of the drug-resistant loci mapped in this paper. Polypeptide length modifications of cytochrome b were observed in mutants deficient in the coQH₂-cyt c red and localized at the BOX1, BOX4 and BOX6 genetic loci (Claisse et al., 1977, 1978) which are precisely the loci allelic to drug resistant mutants as shown in the present work. Taken together these two sets of data provide a strong evidence in favor of the idea that there exist three non contiguous segments of the mitochondrial DNA sequence which code for a single polypeptide sequence of cytochrome b. In each segment mutations which modify the polypeptide sequence can occur leading to the loss (BOX mutants) or to a modification (drug resistant mutants) of the enzyme activity.Chercheur qualifié du Fonds National de la Recherche Scientifique     

广东省南雄盆地白垩系—第三系交界恐龙绝灭问题

广东省南雄盆地中的红层可划分为三个群五个组,大致代表了晚白垩世—始新世的沉积.根据绝对年龄、古地磁测定结果和脊椎动物化石组合性质的综合分析,位于地磁极性带 29R 上部的坪岭组和上湖组之间的分界线被确定为 K/T 界线.对晚白垩世恐龙蛋的研究表明,不同"种"的恐龙蛋是在地磁极性带 29R 的中、下部,也就是说在白垩系—第三系交界之前20～30万年期间绝迹的.而且在这一时期内,所有已发现的蛋壳中,绝大多数蛋壳的厚度和显微结构都显示出明显的病理特征,例如根据随机取样统计,Macroolithus yaotunensis 蛋壳异常结构的出现率,最高可达75%.产生病态恐龙蛋壳的生理机制可以根据发生在现生鸟类的相同病理特征来解释.进一步分析恐龙蛋壳的微量元素和稳定同位素组成,结果显示, Pb, Cu, Mn 等9种元素丰度变化在这一时期达到最大峰值, δ~(18)O 也出现正异常.在这一基础上提出,微量元素的污染和气候突然的变化妨碍了正常蛋壳结构的形成,导致了恐龙的绝灭.这一绝灭过程大约经历了20～30万年.