Bovine thecal cells secrete factor(s) that promote granulosa cell proliferation

To determine if soluble factors (other than steroids) secreted by bovine thecal cells may be involved in local regulation of follicular development, we examined the effects of thecal cell secretory products on the growth of granulosa cells obtained from the same follicles. DNA synthesis (assessed by the incorporation of 3H-thymidine) by granulosa cells plated on coverslips and cocultured with, but not directly in contact with, thecal cells in organ culture dishes in a serum-free medium was 5-fold greater than controls. The effect of the thecal cell-secreted products on DNA synthesis by granulosa cells was significantly higher than the maximum response produced by epidermal growth factor (EGF). Thecal cell-conditioned medium stimulated 3H-thymidine incorporation into the DNA of granulosa cells and a normal rat kidney cell line in a dose-dependent manner. The increases in 3H-thymidine incorporation into granulosa cell DNA subsequently lead to an increase in cell number. Preliminary characterization studies using ultrafiltration membranes indicated that the mitogenic factor was retained in the greater than 10,000 molecular weight fraction. The activity was stable to heating at 90 degrees C for 5 min and was not extracted in ether. The thecal cell-generated growth factor may act as a paracrine regulator of granulosa cell growth, thus providing the dominant follicle with autonomy over other follicles in the cohort.     

Angiogenic activity of human tumor plasma membrane components

Plasma membranes from the human colon adenocarcinoma cell line HT-29 have been isolated and examined for the presence of angiogenic activity. Membrane-associated macromolecules extracted with Triton X-100 were fractionated on immobilized wheat germ agglutinin. The fraction which bound specifically (about 200 ng of protein/mL packed cells) was highly angiogenic when assayed on the chick embryo chorioallantoic membrane. As little as 0.2 ng of this human tumor derived material consistently induced neovascularization. Similarly, 1-2 ng of this material implanted into the rabbit cornea induced new vessel growth (5-8 mm) within 10 days. The plasma membranes of eight other human tumor lines were examined for angiogenic activity. For each, the wheat germ agglutinin bound material induced neovascularization at the low nanogram level. In contrast, the wheat germ agglutinin bound material derived from purified plasma membranes of two normal human diploid fibroblast cell lines failed to induce an angiogenic response on the chick chorioallantoic membrane, even at microgram levels.     

Cloning and sequence analysis of channel catfish heavy chain cDNA indicate phylogenetic diversity within the IgM immunoglobulin family

Catfish cDNA libraries were constructed using the poly(A+) RNA obtained from in vitro stimulated catfish leukocytes. Antigenic analysis with different antisera to catfish Ig resulted in the definition of cDNA clones encoding the catfish H chain. Sequence analysis confirmed that the catfish H chain was definitively identified, based on its similarities with chicken and mouse mu chains. Two clones were each shown to encode part of the CH2 domain, the complete CH3 and CH4 domains, the C-terminus, and a 184-bp 3' untranslated region before the poly(A+) tail. The conservation of domain size and structure is clearly evident. The two cysteines forming the intradomain disulfide bridge, as well as the tryptophans located within each domain, are absolutely conserved. There are four carbohydrate acceptor sites in the catfish H chain, only one of which is phylogenetically conserved. Of the six sequenced H chain clones, one was found to differ in a single base in the CH3, which results in the loss of a carbohydrate acceptor site. Whether this difference indicates isotypic variation between closely related genes or somatic mutation is unresolved. Amino acid sequence comparisons indicate that there is a approximately 24% similarity when the catfish H chain is aligned with mouse mu chains. This is considerably less than the approximately 40% amino acid conservation found between the chicken and mouse mu chain. The amino acid sequence of the catfish H chain is most conserved in the C-terminus (approximately 30%) and the CH4 (approximately 26%); there is less conservation in the CH3 (approximately 20%) when comparisons are made with mouse mu chain. The CH3 domain of the catfish H chain also has different hydropathy properties, when compared with the CH3 domain of the higher vertebrate mu chains. Finally, the sequence of the catfish H chain indicates an unusual arrangement of the cysteines that likely participate in intersubunit and inter-H chain disulfide linkages. The disulfide linkage of these cysteines during Ig polymerization may account for the unusual covalent architecture associated with the catfish tetramer.     

Seed transmission of turnip yellow mosaic virus in winter turnip and winter oilseed rapes

This is the first record of seed transmission of turnip yellow mosaic virus (TYMV) in oilseed and turnip rapes. The seed transmission of TYMV in a naturally infected winter turnip rape (Brassica napus var. silvestris) cultivar Perko PVH was investigated. By ELISA 1.6%, 3.2% and 8.3% seed transmission of the virus was found in seed of plants from three localities. The proportion of infected seeds produced by artificially infected plants of winter oilseed rape (Brassica napus ssp. oleifera) and winter turnip rape cultivars was determined. The virus transmission rate, expressed as the proportion of virus-infected plants which germinated from the seed was for the oilseed rape cvs Jet Neuf 0.1%, Solida 0.4%, Silesia 0.8%, Darmor 1.2%, SL-507 0.2%, SL-509 0.0% and for the winter turnip rape cv. Perko 1.5%. ELISA cannot be used in direct tests on bulk seed lots to estimate proportion of infected seed, but must be used on germinated seedlings.     

Aspects of hadrosaurian cranial anatomy

Supraorbital bones in Saurolophus angustirostris are described, and their presence in all hadrosaurs is suggested. Frontal-nasal and premaxillar-nasal fontanellae are distinguished in hadrosaurs; their presence is explained as connected with growth and considered to he responsible for the variability of crest structures. New data indicating the presence of a cartilaginous diverticulum nasi within the circumnarial depression in Saurobphus ongustirostris are presented. A physiological (respiratory and/or thermoregulatory) function of the nasal diverticulum is proposed.     

华西银腊梅挥发油化学成分的研究

用水蒸气蒸馏法提取华西银腊梅挥发油,并用气相色谱-质谱(GC-MS)联用技术对其挥发油的化学成分进行分析,结果共鉴定了其中的39种成分,所鉴定成分含量约占总检出量的87.83%。其化学成分主要为(Z,Z)-9,12-十八碳二烯酸甲酯(9.00%),壬醛(5.83%),二十一烷(5.69%),二十烷(5.08%),辛炔酸(4.50%),2,6,10,15-四甲基十七烷(3.93%),(Z)-6-十八烯酸甲酯(3.65%),3,8-二甲基十一烷(3.52%),1-十六碳炔(3.31%),肉豆蔻酸(2.86%),月桂醛(2.81%),壬酸(2.23%),5,6,7,7α-四氢-4,4,7α三甲基-2(4H)-苯并呋喃酮(2.18%)等。     

Purification and characterization of heparin-binding endothelial cell growth factors

Thirteen endothelial cell growth factors have been purified to homogeneity by heparin affinity and reversed-phase high performance liquid chromatography, and their chromatographic and electrophoretic properties were compared. The amino acid compositions of 10 of these mitogens have also been determined. The results indicate that these heparin-binding growth factors (HBGFs) can be subdivided into two classes. Class 1 HBGFs are anionic mitogens of molecular weight 15,000-17,000 found in high levels in neural tissue and include acidic brain fibroblast growth factor and retina-derived growth factor. Class 2 HBGFs are cationic mitogens of molecular weight 18,000-20,000 found in a variety of normal tissues and are typified by pituitary fibroblast growth factor and cartilage-derived growth factor. Typical class 2 HBGFs have also been isolated from a rat chondrosarcoma, a human melanoma, and a human hepatoma, suggesting that tumors do not make a structurally distinct HBGF class. These results provide a sound basis for the evaluation of the HBGFs purified from a variety of tissues and species and for the delineation of their normal and pathological functions in vivo.     

Slr4, a newly identified S-layer protein from marine Gammaproteobacteria,is a major biofilm matrix component

S-layers are paracrystalline proteinaceous lattices that surround prokaryotic cells, forming a critical interface between the cells and their extracellular environment. Here, we report the discovery of a novel S-layer protein present in the Gram-negative marine organism, Pseudoalteromonas tunicata D2. An uncharacterized protein (EAR28894) was identified as the most abundant protein in planktonic cultures and biofilms. Bioinformatic methods predicted a beta-helical structure for EAR28894 similar to the Caulobacter S-layer protein, RsaA, despite sharing less than 20% sequence identity. Transmission electron microscopy revealed that purified EAR28894 protein assembled into paracrystalline sheets with a unique square lattice symmetry and a unit cell spacing of ~9.1 nm. An S-layer was found surrounding the outer membrane in wild-type cells and completely removed from cells in an EAR28894 deletion mutant. S-layer material also appeared to be “shed” from wild-type cells and was highly abundant in the extracellular matrix where it is associated with outer membrane vesicles and other matrix components. EAR28894 and its homologs form a new family of S-layer proteins that are widely distributed in Gammaproteobacteria including species of Pseudoalteromonas and Vibrio, and found exclusively in marine metagenomes. We propose the name Slr4 for this novel protein family.     

European checkerspots (Melitaeini: Lepidoptera,Nymphalidae) are not aposematic – the point of view of great tits (Parus major)

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Multiplex panels of polymorphic microsatellite loci for two cryptic bat species of the genus Pipistrellus,developed by cross‐species amplification within the family Vespertilionidae

The paper presents multiplex panels of polymorphic microsatellites for two closely related cryptic species Pipistrellus pipistrellus and Pipistrellus pygmaeus. We tested the cross‐species amplification of 34 microsatellite loci, originally developed for five vespertilionid bat species. Ten and nine polymorphic loci in P. pipistrellus (mean number of alleles per locus = 10.5) and P. pygmaeus (8.1), respectively, in three multiplex polymerase chain reactions per species were amplified. All loci can be analysed in a single fragment analysis and can be used as markers to the study of evolution and the ecology of structured populations of socially living bats.