Evolution of green lacewings (Neuroptera: Chrysopidae): a molecular supermatrix approach

We present a time‐calibrated phylogeny of the charismatic green lacewings (Neuroptera: Chrysopidae). Previous phylogenetic studies on the family using DNA sequences have suffered from sparse taxon sampling and/or limited amounts of data. Here we combine all available previously published DNA sequence data and add to it new DNA sequences generated for this study. We analysed these data in a supermatrix using Bayesian and maximum likelihood methods and provide a phylogenetic hypothesis for the family that recovers strong support for the monophyly of all subfamilies and resolves relationships among a large proportion of chrysopine genera. Chrysopinae tribes Leucochrysini and Belonopterygini were recovered as monophyletic sister clades, while the species‐rich tribe Chrysopini was rendered paraphyletic by Ankylopterygini. Relationships among the subfamilies were resolved, although with relatively low statistical support, and the topology varied based on the method of analysis. Greatest support was found for Apochrysinae as sister to Nothochrysinae and Chrysopinae, which is in contrast to traditional concepts that place Nothochrysinae as sister to the rest of the family. Divergence estimates suggest that the stem groups to the various subfamilies diverged during the Triassic‐Jurassic, and that stem groups of the chrysopine tribes diverged during the Cretaceous.     

Hypoxia-inducible factor 1α regulates branching morphogenesis during kidney development

The kidneys are exposed to hypoxic conditions during development. Hypoxia-inducible factor (HIF), an important mediator of the response to hypoxia, is believed to have an important role in development. However, the relationship between HIF and branching morphogenesis has not been elucidated clearly.     

Comparative study of the mucin-type sugar chains of human chorionic gonadotropin present in the urine of patients with trophoblastic diseases and healthy pregnant women

Human chorionic gonadotropins (hCGs) highly purified from the urine of patients with trophoblastic diseases and of healthy pregnant women contain approximately four mucin-type sugar chains in one molecule. The structures of these sugar chains were studied comparatively by using a new sensitive method to obtain mucin-type sugar chains quantitatively as radioactive oligosaccharides from a small amount of glycoproteins. The mucin-type sugar chains of all hCGs include sialylated and nonsialylated Gal beta 1----3GalNAc and Gal beta 1----4GlcNAc beta 1----6(Gal beta 1----3)GalNAc. In the case of normal hCG and hydatidiform mole hCG, oligosaccharides containing the tetrasaccharide core occupy approximately 10% of the total mucin-type sugar chains. The ratio of the tetrasaccharide containing oligosaccharides is increased prominently to approximately 60% in choriocarcinoma hCG. The proportion in invasive mole hCG was also increased, but less than the proportion of choriocarcinoma hCG.     

The APC/C activator Cdh1 regulates the G2/M transition during differentiation of placental trophoblast stem cells

Differentiation of placental trophoblast stem (TS) cells to trophoblast giant (TG) cells is accompanied by transition from a mitotic cell cycle to an endocycle. Here, we report that Cdh1, a regulator of the anaphase-promoting complex/cyclosome (APC/C), negatively regulates mitotic entry upon the mitotic/endocycle transition. TS cells derived from homozygous Cdh1 gene-trapped (Cdh1^GT/GT) murine embryos accumulated mitotic cyclins and precociously entered mitosis after induction of TS cell differentiation, indicating that Cdh1 is required for the switch from mitosis to the endocycle. Furthermore, the Cdh1^GT/GT TS cells and placenta showed aberrant expression of placental differentiation markers. These data highlight an important role of Cdh1 in the G2/M transition during placental differentiation.     

Watersoluble synthetic nucleic acid analogs--polyethyleneimine derivatives containing nucleic acid bases--conformation and interactionwith nucleic acids

Water soluble polyethyleneimine derivatives containing nucleic acid bases were found to interact with polynucleotides, DNA, RNA. The conformational change by formation of complex was observed by CD spectra and was discussed with the hypochromicity in UV spectra. The rates of interactions between nucleic acid bases in polymers were slow as shown by UV spectra, but the conformational changes of the polynucleotides were fast as shown by CD spectra. In the case of the uracil derivative (PEI-Hse-Ura), high value of CD spectra [theta] 2.80 = -8.0 x 10(-4) for the complex with DNA might be caused by psi type conformation of DNA.     

Application of coomassie brilliant blue staining to cultured hepatocytes

Coomassie brilliant blue staining developed by Pena (1980) was applied to cultured hepatocytes of adult rats with some modifications. Many of organelles in the cytoplasms were clearly visible as blue granules by this method. Various cytoskeletal elements were also visualized clearly. Because of its simplicity, Coomassie blue staining proved to be a very powerful tool for study of morphological changes of cell organelles and cytoskeletal systems of cultured hepatocytes.     

Extensin Secreted into the Culture Medium by Tobacco Cells I. Purification and Some Properties

The medium of 12-day-old culturs of tobacco cells (Nicotianatabacum L., var Xanthi; line XD-6S) contain c.a. 160mg/literof protein, of which 14% of the constituent ami no acids werefound to be hydroxyproline. By sequential column chromatographiesand CsCl density-gradient centrifugation, a basic hydroxyproline-richglycoprotein was purified from the medium and found to havean amino acid composition typical of extensin; with a high levelof hydroxyproline (33mole%), tyrosine (13%), and lysine (14%).The glycoprotein contained 42% (w/w) of sugars, among whicharabinose was the major component (85%). The proportion of thisextensin in the proteins in the culture medium was estimatedto be much higher than that of arabino-galactan protein (about5 times higher) on a protein basis, with extensin comprisingbetween 25% and 41%, and probably about 37% of the proteinsin the medium. (Received September 19, 1988; Accepted December 26, 1988)     

Effects of growth hormone releasing factor on pancreatic secretion in vivo and in vitro

Growth hormone releasing factor (GRF), a 44-residue peptide originally isolated from human pancreatic tumors, shows structural similarities to the members of the secretin-vasoactive intestinal peptide (VIP) peptides. This study was designed to determine the effects of human GRF (hGRF-(1-44] on pancreatic secretion in vivo in conscious dogs and in vitro in dispersed rat pancreatic acini. GRF given i.v. in graded doses in dogs caused a small but significant stimulation of pancreatic HCO3- and protein outputs and potentiated secretin- and cholecystokinin (CCK)-induced pancreatic HCO3- but not protein secretion. When given together with somatostatin, GRF failed to reverse the inhibitory action of this peptide on HCO3- and protein responses to secretin plus CCK in dogs. Studies in vitro dispersed rat pancreatic acini showed that GRF added to the incubation medium of these acini caused an increase in basal amylase release and shifted to the left the amylase dose-response curve to caerulein and urecholine but failed to affect the amylase response to VIP. This study indicates that GRF in vivo stimulates basal and augments secretin- or CCK-induced pancreatic HCO3- secretion and that this is probably due to direct stimulatory action of the peptide on pancreatic secretory cells.     

Immunohistochemical localization of proteoglycans in interstitial elements of human pancreas and biliary system

Summary The immunohistochemical localization of large proteoglycan and small proteoglycan was observed, using antibodies 2B1 and 6B6 (Sobueet al., 1988, 1989a), in fetal and adult pancreas and biliary system as well as in tumour tissues, obtained from 11 autopsies and 74 biopsies. The distribution of chondroitin 4- and 6-sulphate side chains, type I and IV collagen and elastin were also studied. In adult pancreas and all the biliary tracts examined, periductal fibrous tissues consisted mainly of dermatan sulphate small proteoglycan with networks of fibrous elements, which were composed of large proteoglycan, elastin, type I collagen and type IV collagen. In the interstitial components of cystadenoma of pancreas and biliary duct carcinoma, similar small proteoglycan-rich components were relatively abundant, although large proteoglycan was present in much larger amounts than that in non-neoplastic adult tissues. In some cholangiomas, the extra-and intracellular hyaline globules formed by the carcinoma cells were found to contain chondroitin sulphate large proteoglycan, laminin and fibronectin.The distribution of proteoglycans was observed to be different in the arterial walls of the interlobular tissues of the adult and the fetal pancreas. The biological significance of large and small proteoglycans in the interstitial connective tissues was discussed.