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Notes: PER values determined for corn gluten meal (CGM) and CGM fermented with Aspergillus oryzae NRRL 1988 were not significantly different (P 〉 0.05) and both diets failed to meet maintenance requirements of rats. In order to characterize some of the changes that occur during fungal fermentation, CGM was also fermented for 4 days at 28°C with A. oryzae NRRL 1988 and NRRL 506 and Rhizopus oligosporus NRRL 2710 and NRRL 2549, respectively. Proteolytic activity, pH, and nitrogen content increased rapidly between 20 and 70 hr for all the fungi. Decreases in some amino acids were observed, possibly due to their catabolism by the molds. Lysine as a proportion of total essential amino acids released by pepsin and pancreatin in vitro was increased as a result of these fungal fermentations.

Notes: Molds commonly used in Oriental food fermentation have been examined for their ability to produce phytase. Except for Mucor dispersus NRRL 3103 and Actinomucor elegans NRRL 3104, all the other molds tested produced both extra- and intracellular phytase. The enzyme produced by Aspergillus oryzae NRRL 1988 was purified by acetone fractionation, gel filtration, and diethylaminoethyl-cellulose chromatography. The phytase was successfully separated from an acid phosphatase, and a 44-fold increase in specific activity was observed. The pH optimum of 5.3 characterizes the enzyme as an acid phosphohydrolase, and its maximum activity at 50°C suggests a relatively high thermostability. The enzyme is also fairly stable over a pH range 3.5-7.8 at 25°C. The A. oryzae phytase is active with either phytic acid or glycerophosphate. as substrate, but it hydrolyzes phytic acid twice as fast as it does glycerophosphate. However, the enzyme is partially inhibited by high concentration of phytic acid. The Km value of A. oryzae phytase was estimated as 0.47 mM and Vmax was 11.9 μmoles Pi per mg per mg protein.

Notes: We have fabricated unilayer electroluminescent devices from soluble poly(p-pyridine) (PPy). The solubility of PPy in weak acids allows direct spin casting of the polymer films. The electroluminescence spectrum peaks at 2.5 eV (497 nm) corresponding to white light weighted towards the blue end of the spectrum. The photoluminescence spectrum peaks at 2.35 eV (530 nm). The operating voltages of the devices ranged from 4 to 12 V with current densities of 6 to 8 mA/mm2. We compare our devices with similar blue emitting devices based on poly(p-phenylene). © 1995 American Institute of Physics.

Notes: Summary.  Factor X (FX) deficiency is a rare bleeding disorder inherited as an autosomal recessive trait. In this study, we investigated the molecular basis of FX deficiency in a Chinese pedigree. The proposita showed a markedly prolonged activated partial thromboplastin time and a mild prolongation of prothrombin time. The levels of FX antigen and FX activity were 58.6% and 2.5%, respectively. Molecular analysis revealed that the proposita was compound heterozygous for two novel mutations: IVS1 + 1G 〉 A and G1185A (Arg347His). The aberrant transcripts from the IVS1 + 1G 〉 A mutant allele were not detected by analyzing the splicing pattern of ectopic transcripts in leukocytes of the patient with nested polymerase chain reaction after reverse transcription. We thus hypothesize that the mRNA molecules originating from the IVS1 + 1G 〉 A mutation were rapidly destroyed in vivo. Site-directed mutagenesis of FX cDNA was used to introduce FXG1185A mutation, and wild-type as well as mutant FX proteins were expressed by transient transfection in HEK 293 cells. Normal FX antigen levels both in the conditioned media of cells expressing the mutant and in cell lysates were detected by an enzyme-linked immunoadsorbent assay. Evaluation of wild-type and mutant coagulant activity demonstrated that the FX molecules carrying the Arg347His mutation have dramatically decreased activity.

Notes: Summary.  To investigate the molecular defects in two Chinese pedigrees with inherited factor V (FV) deficiency.A 37-year-old male (proband 1) and an 18-month-old boy (proband 2) were diagnosed as inherited coagulation FV deficiency by severely reduced plasma levels of FV activity and antigen. All 25 exons and their flanking sequence of F5 gene were amplified by polymerase chain reaction (PCR) for both probands and the PCR products were directly sequenced. Total RNA was extracted from the peripheral lymphocytes of proband 1 for detecting the changes at mRNA level.The homozygous deletion IVS8 −2A〉G was identified in the F5 gene of proband 1 and complementary DNA (cDNA) analysis revealed the abolishment of the canonical splicing site by the mutation and the activation of the cryptic acceptor site 24 bp upstream instead. The insertion introduced eight additional amino acids (AA) into the FV protein. Two heterozygous mutations of F5 gene were discovered in proband 2. The 2238-9del AG in exon 13 introduced a premature termination code at 689 AA and the substitution of G6410 by T in exon 23 lead to the missense mutation Gly2079Val.Three F5 gene mutations, IVS8 −2A〉G, 2238-9del AG and G6410T, have been identified in two Chinese pedigree with congenital FV deficiency, respectively.

Notes: We have previously demonstrated that intra-hippocampal injection of corticotrophin-releasing factor improved memory retention of an inhibitory avoidance learning in rats; while the electrophysiological effects corticotrophin-releasing factor produces on hippocampal neurons are largely uncharacterized. In the present study, we found that corticotrophin-releasing factor injected into the dentate gyrus of hippocampus produced a dose-dependent and long-lasting enhancement in synaptic efficacy of these neurons, as measured by an increase in the amplitude and slope of population excitatory postsynaptic potentials, as well as the amplitude of population spike. The onset of corticotrophin-releasing factor-induced potentiation was slow. It was observed approximately 40–60 min after corticotrophin-releasing factor administration and lasted for more than 5 h. This effect of corticotrophin-releasing factor was blocked by pretreatment with the cyclase-adenosine-3,5-monophosphate (cAMP) inhibitor Rp-adenosine-3,5-cyclic monophosphothiolate triethylamine (Rp-cAMPS) and partially blocked by the N-methyl-D-aspartate receptor antagonist MK-801. Further, pretreatment with corticotrophin-releasing factor receptor antagonist dose-dependently diminished tetanization-induced long-term potentiation, and corticotrophin-releasing factor and tetanic stimuli had an additive effect on hippocampal neuron excitation. Moreover, direct injection of corticotrophin-releasing factor increased cAMP level in the dentate gyrus. These results together suggest that corticotrophin-releasing factor-induced potentiation simulates the late phase of tetanization-induced long-term potentiation and cAMP seems to be the messenger mediating this effect. Moreover, corticotrophin-releasing factor-induced potentiation and long-term potentiation may share some similar mechanisms, and corticotrophin-releasing factor is probably involved in the neural circuits underlying long-term potentiation. Thus, corticotrophin-releasing factor may play an important role in modulating synaptic plasticity in the hippocampus.

Notes: Most polymer electroluminescent devices to date are represented as tunnel diodes and operate under direct-current (dc) driving field. Here we report the fabrication of symmetrically configured alternating-current (ac) light-emitting (SCALE) devices based on conjugated polymers. The new devices consist of an emissive polymer layer sandwiched between two redox polymer layers. This configuration enables the SCALE devices to work under both forward and reverse dc bias as well as in ac modes. The nearly ohmic electrode/redox polymer contacts improve the charge injection efficiency significantly and make the SCALE device operation insensitive to electrode work functions. Symmetric operation supports the key role of redox polymer/emissive polymer interface states. © 1996 American Institute of Physics.

Notes: In the developing wheat grain, photosynthate is transferred longitudinally along the crease phloem and then laterally into the endosperm cavity through the crease vascular parenchyma, pigment strand and nucellar projection. In order to clarify this cellular pathway of photosynthate unloading, and hence the controlling mechanism of grain filling, the potential for symplastic and apoplastic transfer was examined through structural and histochemical studies on these tissue types. It was found that cells in the crease region from the phloem to the nucellar projection are interconnected by numerous plasmodesmata and have dense cytoplasm with abundant mitochondria. Histochemical studies confirmed that, at the stage of grain development studied, an apoplastic barrier exists in the cell walls of the pigment strand. This barrier is composed of lignin, phenolics and suberin. The potential capacity for symplastic transfer, determined by measuring plasmodesmatal frequencies and computing potential sucrose fluxes through these plasmodesmata, indicated that there is sufficient plasmodesmatal cross-sectional area to support symplastic unloading of photosynthate at the rate required for normal grain growth. The potential capacity for membrane transport of sucrose to the apoplast was assessed by measuring plasma membrane surface areas of the various cell types and computing potential plasma membrane fluxes of sucrose. These fluxes indicated that the combined plasma membrane surface areas of the sieve element–companion cell (se–cc) complexes, vascular parenchyma and pigment strand are not sufficient to allow sucrose transfer to the apoplast at the observed rates. In contrast, the wall ingrowths of the transfer cells in the nucellar projection amplify the membrane surface area up to 22-fold, supporting the observed rates of sucrose transfer into the endosperm cavity. We conclude that photosynthate moves via the symplast from the se–cc complexes to the nucellar projection transfer cells, from where it is transferred across the plasma membrane into the endosperm cavity. The apoplastic barrier in the pigment strand is considered to restrict solute movement to the symplast and block apoplastic solute exchange between maternal and embryonic tissues. The implications of this cellular pathway in relation to the control of photosynthate transfer in the developing grain are discussed.

Notes: The cellular pathway of sucrose transfer from the endosperm cavity to the starchy endosperm of developing grains of wheat (Triticum turgidum) has been elucidated. The modified aleurone and sub-aleurone cells exhibit a dense cytoplasm enriched in mitochondria and endoplasmic relicilium. Significantly, the sub-aleurone cells are characterized by secondary wall ingrowths. Numerous plasmodesmata interconnect all cells between the modified aleurone and starchy endosperm. The pro-tonophore carbonylcyanide-m-chlorophenyl hydrazone (CCCP) slowed [14C]sucrose uptake by grain tissue slices enriched in modified aleurone and sub-aleurone cells but had no effect on uptake by the starchy endosperm. The fluorescent weak acid sulphorhodamine G (SRG) was preferentially accumulated by the modified aleurone and sub-aleurone cells, and this uptake was sensitive to CCCP. The combined plasma membrane surface areas of the modified aleurone and sub-aleurone cells appeared to be sufficient to support the in vivo rates of sucrose transfer to the starchy endosperm. Plasmolysis of intact excised grain inhibited [14C]sucrose transfer from the endosperm cavity to the starchy endosperm. The sulphydryl group modifier p-chloromercuribenzenesulphonie acid (PCMBS) decreased [14C]sucrose uptake by the modified aleurone and sub-aleurone cells but had little effect on uptake by the starchy endosperm. In contrast, when PCMBS and [14C]sucrose were supplied to the endosperm cavity of intact excised grain, PCMBS slowed accumulation by all tissues equally. Estimates of potential sucrose fluxes through the interconnecting plasmodesmata were found to be within the published range. It is concluded that the bulk of sucrose is accumulated from the endosperm cavity by the modified aleurone and sub-aleurone cells and subsequently transferred through the symplast to the starchy endosperm.