Induction of IgG1 and IgE responses to protein-conjugated and unconjugated β-lactam antibiotics in the mouse-efficacy of Freund's complete adjuvant

Summary One or two injections two weeks apart of protein-conjugated penicillin G, cephalothin or cefmetazole emulsified with Freund's complete adjuvant were quite effective in producing anti-antibiotic antibodies of the IgE as well as of the IgG₁ class in mice. Long-lasting and boostable production of both antibody classes was also obtained against unconjugated cephalothin or cefmetazole, though the positivity depended on the mouse strain.     

The Use of Soluble Polymer in Enzyalc Reactions

1 Results Enzyme-mediated kinetic resolution of racemic esters is one of the practical methods for the preparation of optically active compounds. In the reaction process, the products and the substrates could be separated mainly by column chromatography. The most tedious and wasteful purification step is the bottleneck to a sustainable production. We already reported enantioselective hydrolysis of poly(ethylene glycol)(PEG)-supported carbonates which were soluble in some kinds of solvent[1-2]. Here, we ...     

Heterozygous mutations of the kinesin KIF21A in congenital fibrosis of the extraocular muscles type 1 (CFEOM1)

Congenital fibrosis of the extraocular muscles type 1 (CFEOM1; OMIM #135700) is an autosomal dominant strabismus disorder associated with defects of the oculomotor nerve. We show that individuals with CFEOM1 harbor heterozygous missense mutations in a kinesin motor protein encoded by KIF21A. We identified six different mutations in 44 of 45 probands. The primary mutational hotspots are in the stalk domain, highlighting an important new role for KIF21A and its stalk in the formation of the oculomotor axis.     

He and Ar isotopes in mantle megacryst minerals from Nushan and Yingfengling in Southeast China

He and Ar isotopic compositions of megacrystal minerals from mantle xenoliths were measured by the technique of vacuum crushing extraction. The used samples were clinopyroxene, garnet and ilmenite in Cenozoic alkaline basalts, which were from Nushan in Anhui Province and Ying-fengling in Guangdong Province, respectively, and represented materials from the upper mantle in the continental margin of SE China. The results show ^3He/^4He ratios of 7.99 Ra to 8.58 Ra, consistent with the characteristic ratios of the MORB-type mantle. ^40Ar／^39Ar ratios vary from 313 to 909, suggesting a binary mixing between the MORB-type mantle and air argons. This may reflect the incorporation of the air argon absorbed in oceanic sediments into the mantle beneath the continental margin by subduction of oceanic plate. This study presents the first report that ilmenite megacrysts contain abundant fluid inclusions and noble gases in the mantle xenoliths.     

Quantitative reconstruction of the paleosalinity in the Daihai Lake, Inner Mongolia, China

Ostracods are small bivalved aquatic crustaceans. They secrete shells of low-Mg calcite that are often preserved in lake sediments. Recent work has shown that the uptake of trace elements (especially Mg and Sr) into the shell may be a function of the salinity and temperature of the host water. We measured Sr/Ca ratios in living ostracod valves from the species of genus Limnocythere cf. inopinata and Sr²⁺/Ca²⁺ ratios of the host water to calculate distribution coefficient of genus Limnocythere cf. inopinata in the Daihai Lake. A function for Sr²⁺/Ca²⁺ ratio and salinity was established by measuring a series of Sr²⁺/Ca²⁺ ratios and salinities of the lake water in different places of the Daihai Lake. Finally paleosalinities of the lake water were quantitatively reconstructed by the Sr/Ca ratios of ostracod shells of the same species in sediment core of the Daihai Lake.     

Spred is a Sprouty-related suppressor of Ras signalling

Cellular proliferation, and differentiation of cells in response to extracellular signals, are controlled by the signal transduction pathway of Ras, Raf and MAP (mitogen-activated protein) kinase. The mechanisms that regulate this pathway are not well known. Here we describe two structurally similar tyrosine kinase substrates, Spred-1 and Spred-2. These two proteins contain a cysteine-rich domain related to Sprouty (the SPR domain) at the carboxy terminus. In Drosophila, Sprouty inhibits the signalling by receptors of fibroblast growth factor (FGF) and epidermal growth factor (EGF) by suppressing the MAP kinase pathway. Like Sprouty, Spred inhibited growth-factor-mediated activation of MAP kinase. The Ras-MAP kinase pathway is essential in the differentiation of neuronal cells and myocytes. Expression of a dominant negative form of Spred and Spred-antibody microinjection revealed that endogenous Spred regulates differentiation in these types of cells. Spred constitutively associated with Ras but did not prevent activation of Ras or membrane translocation of Raf. Instead, Spred inhibited the activation of MAP kinase by suppressing phosphorylation and activation of Raf. Spred may represent a class of proteins that modulate Ras-Raf interaction and MAP kinase signalling.     

Paramyosin and actin in schistosomal teguments

Schistosomes are blood-dwelling trematode parasites that infect 200 million people in developing countries. The critical role served by the tegument in immune evasion and parasite homeostasis suggests that a detailed knowledge of tegumental components would be helpful in the design of new drugs and the production of vaccines. We demonstrate here, by immunoelectron microscopy, that the cytoskeletal proteins actin and paramyosin are organized into major tegumental structures of Schistosoma mansoni. The surface spines are composed of paracrystalline arrays of actin filaments. Actin is also present in areas recovering from damage, implying an important role for this structural protein in tegumental repair. Paramyosin exists predominantly in the tegument in a non-filamentous form, the membrane-bounded elongate bodies. The localization of this protein to the tegument of the parasite is the likely basis for resistance to S. mansoni observed in mice immunized with paramyosin (refs 1, 2 and T. P. Flanigen et al., in preparation).     

Determination of polyamine oxidase activities in human tissues

Summary A very simple fluorometric assay for polyamine oxidase (PAO) in tissues, with N¹-monoacetylspermine as substrate, is described. The PAO was present in all human organs tested; it was highest in the liver, followed by the testis, kidney, spleen and small intestine.     

Sleep in parabiosis

Résumé Le taux de la synchronization de la phase de sommeil chez le rat parabiotique est plus élevé que chez le rat de controle, particulièrement en cas de sommeil paradoxal (P<0.001). Ces resultats indiquent que le facteur humoral joue un grand rôle dans le déclenchement et l'anticipation du sommeil paradoxal.     

Unique cell lines harbouring both Epstein-Barr virus and adult T-cell leukaemia virus, established from leukaemia patients

Members of three distinct classes of animal virus have been associated with naturally occurring neoplasias in man: Epstein--Barr virus (EBV), a DNA virus belonging to herpesvirus group, papillomavirus, and a novel human RNA (retro) virus, human T-cell leukemia virus or adult T-cell leukaemia (ATL) virus. We have established seven continuous cell lines from ATL patients and 0.1-7% of these cells consistently express ATL-specific antigens (ATLA). EBV-associated nuclear antigen (EBNA) is also found in more than 90% of these cells. We have cloned cells from two of these lines and show here that both ATLA and EBNA were present in the same B-cell clone carrying surface immunoglobulin (sIg).