First Report of Neofusicoccum vitifusiforme Causing Blueberry Blight of Blueberry in China.

In May 2008, symptoms of blueberry blight were observed on half-high blueberry (Vaccinium corymbosum L.) in a plant nursery in Anning, Yunnan Province. Symptoms included dieback and bud and branch blight. Symptomatic plant samples were washed with running tap water, disinfected with 2% sodium hypochlorite and then 70% alcohol, rinsed in sterile distilled water, plated on potato dextrose agar (PDA), and incubated at 26°C. Conidia forming on PDA were hyaline, granular, fusoid to ellipsoid, widest in the upper third with an obtuse apex and flattened, subtruncate base, and 18 to 21 × 4.5 to 8 µm. The pathogen was also identified to the species level by sequencing the ribosomal internal transcribed spacer regions 1 and 2 (ITSI-5.8S-ITS2) and the translation elongation factor 1-alpha (EF1-α). BLAST searches at GenBank showed the highest nucleotide sequence identity with Neofusicoccum vitifusiforme reference sequence (ITS: >98%, EF638785; EF1-α: 100%, EF638744 and AY343343). Representative sequences of isolates from both regions were deposited in GenBank (ITS: Accession No. HM131604; EF1-α: Accession No. HM454277). Pathogenicity tests were conducted on 2-year-old blueberry seedlings (half-high blueberry). Mycelial plugs (3 mm in diameter) of N. vitifusiforme from actively growing colonies (PDA) were applied to same-size bark wounds in the center of the stems. Inoculation wounds were wrapped with Parafilm. Control seedlings received sterile PDA plugs. Inoculated and control seedlings (five each) were kept in a greenhouse and watered as needed. After 2 weeks, all of the inoculated but none of the control blueberry seedlings showed dark vascular stem tissue. N. vitifusiforme was reisolated from symptomatic tissues, thus fulfilling Koch's postulates. N. vitifusiforme has been reported as a pathogen of olive (2), plum, peach (1), and grapevine (3). To our knowledge, this is the first report of N. vitifusiforme on blueberry in China as well as worldwide. References: (1) U. Damm et al. Mycologia 99:664, 2007. (2) C. Lazzizera et al. Plant Pathol. 57:948, 2008. (3) J. M. van Niekerk et al. Mycologia 96:781, 2004.

Subharmonic gap structure of normal-state conductance and thermoelectric effect in a graphene-based nano device.

Using the quantum transport of chiral Dirac fermions in graphene, we investigate the normal-state conductance and thermoelectric effect of a nano device under the ballistic superconductor-graphene-superconductor (SGS) model. Because of the Josephson effect and Andreev reflections, there exists an oscillatory behavior of the normal-state conductance flowing through the successive discrete energy levels on a finite-sized graphene contacted to the superconducting leads. The normal-state conductance displays a rich structure of subharmonic gaps controlled by means of a gate voltage on the discrete energy levels near the Fermi energy. Since the Fermi energy is an essential factor in determining the nature of conduction such as n or p type, we study the thermoelectric effect over the graphene-based nano device. It is shown that the thermoelectric effect can provide information on the location of the Fermi energy with respect to the energy levels of the finite-sized graphene.

Inhibition of the EGF-induced activation of phospholipase C-gamma1 by a single chain antibody fragment.

Phospholipase C-gamma1(PLC-gamma1) is known to play an essential role in various cellular responses, such as proliferation and tumorigenesis, and PLC-gamma1-specific inhibitors are commonly employed to investigate the mechanism of the PLC-gamma1-mediated signaling pathway. In this study, we developed a single chain antibody fragment (scFv) as a blocker for PLC-gamma1 mediated signaling. scFv, designated F7-scFv, specifically bound to PLC-gamma1 with high affinity (K(d)=1.9x10(-8) M) in vitro. F7-scFv also bound to PLC-gamma1 in vivo and altered the distribution pattern of PLC-gamma1 from the cytoplasm to the intracellular aggregates, where F7-scFv was localized. Moreover, F7-scFv interrupted the EGF-induced translocation of PLC-gamma1 from the cytosol to the membrane ruffle and attenuated EGF-induced inositol phosphates generation and intracellular calcium mobilization. These results indicate that F7-scFv blocks EGF-induced PLC-gamma1 activation by causing sequestering of PLC-gamma1 into intracellular aggregates, and may therefore be useful in studies of the PLC-gamma1-mediated signaling pathway.

Structure-activity analysis of buforin II, a histone H2A-derived antimicrobial peptide: the proline hinge is responsible for the cell-penetrating ability of buforin II.

Buforin II is a 21-aa potent antimicrobial peptide that forms, in a hydrophobic medium, an amphipathic structure consisting of an N-terminal random coil region (residues 1-4), an extended helical region (residues 5-10), a hinge (residue 11), and a C-terminal regular alpha-helical region (residues 12-21). To elucidate the structural features of buforin II that are required for its potent antimicrobial activity, we synthesized a series of N- and C-terminally truncated or amino acid-substituted synthetic buforin II analogs and examined their antimicrobial activity and mechanism of action. Deletion of the N-terminal random coil region increased the antibacterial activity approximately 2-fold, but further N-terminal truncation yielded peptide analogs with progressively decreasing activity. Removal of four amino acids from the C-terminal end of buforin II resulted in a complete loss of antimicrobial activity. The substitution of leucine for the proline hinge decreased significantly the antimicrobial activity. Confocal fluorescence microscopic studies showed that buforin II analogs with a proline hinge penetrated the cell membrane without permeabilization and accumulated in the cytoplasm. However, removal of the proline hinge abrogated the ability of the peptide to enter cells, and buforin II analogs without a proline hinge localized on the cell surface, permeabilizing the cell membrane. In addition, the cell-penetrating efficiency of buforin II and its truncated analogs, which depended on the alpha-helical content of the peptides, correlated linearly with their antimicrobial potency. Our results demonstrate clearly that the proline hinge is responsible for the cell-penetrating ability of buforin II, and the cell-penetrating efficiency determines the antimicrobial potency of the peptide.

Resolution of ST-segment elevation after streptokinase therapy in anterior versus inferior wall myocardial infarction.

BACKGROUND: Resolution of ST-segment elevation is the best bedside predictor of myocardial reperfusion. HYPOTHESIS: This study was conducted to examine the resolution of ST-segment elevation after streptokinase therapy in anterior versus inferior acute myocardial infarction (MI) and to corroborate it with echocardiographic and coronary angiographic data. METHODS: The study population consisted of 70 patients, 35 each in the anterior and inferior MI groups. The electrocardiograms (ECGs) were recorded before, on completion of, and on Days 1 and 2 post streptokinase therapy. The resolution of ST segment determined from post-streptokinase ECGs was compared between the two groups and correlated with echocardiographic and coronary angiographic data. RESULTS: On completion of and on Day 1 post streptokinase therapy, ST-segment resolution in both groups was not significantly different. On Day 2 post streptokinase therapy, resolution of the ST segment per lead was significantly lower in anterior than that in inferior MI (61 +/- 21% anterior vs. 77 +/- 21% inferior, p 0.003). The number of patients with akinesis of infarct-related ventricular wall was significantly higher (17 anterior vs. 7 inferior, p 0.02), and left ventricular ejection fraction was significantly lower in anterior MI (39 +/- 7% anterior vs. 48 +/- 8% inferior, p < 0.01). There was no significant difference in coronary angiographic data. One patient in each group demonstrated normal coronary arteries. CONCLUSIONS: The resolution of ST-segment elevation on the completion of and on Day 1 post streptokinase therapy was comparable between anterior and inferior MI. The significantly less frequent resolution of ST-segment elevation in anterior MI on Day 2 post streptokinase could be due to more akinesis, larger infarct size, and worse systolic function rather than due to failure to open the infarct-related vessel.

Phorbol myristate acetate-dependent association of protein kinase C alpha with phospholipase D1 in intact cells.

A phospholipase D1 (PLD1) was purified from rat brain by the use of antibody-coupled protein A Sepharose. We found that protein kinase C alp (PKCalpha) stimulated PLD1 activity in the presence of phorbol myristate acetate (PMA). PMA-dependent association of PKCalpha with PLD1 was verified in NIH-3T3 fibroblast cells, and COS7 cells transiently expressing PLD1 as well as in vitro suggesting that the activation of PLD1 resulted from direct association of PKCalpha with PLD1.

Cloning and characterization of cDNAs encoding VH and VL of a monoclonal anti-CEA antibody (CEA 79) cross-reactive with NCA-95 and generation of a single-chain Fv molecule (scFv).

We cloned complementary DNA (cDNA) encoding the variable regions of heavy chain (VH) and of light chain (VL) of a monoclonal anti-carcinoembryonic antigen (CEA) antibody cross-reactive with nonspecific cross-reacting antigen-95 (NCA-95), which had been previously prepared and designated as CEA 79 (gamma 2a, kappa). From these cDNAs, a phagemid expression vector for the CEA79 single chain variable fragment (scFv) was generated. Enzyme-linked immunosorbent assay (ELISA), competitive ELISAs, and Western blotting confirmed that the scFv displayed on the surface of the bacteriophage had retained affinity for CEA and NCA-95. We then determined the nucleotide sequences of the cloned cDNAs for VH and VL. The sequence analysis revealed that VH and VL of the CEA 79 antibody represent new members of the mouse heavy chain subgroup "miscellaneous" and the kappa light chain subgroup "V", respectively.

Scrub typhus in Korea: importance of early clinical diagnosis in this newly recognized endemic area.

Scrub typhus became a well recognized infectious disease threat to military operations in the Pacific Theater during World War II. Early diagnosis and treatment with tetracycline or chloramphenicol dramatically reduces the mortality and morbidity of this disease. Korea is a newly recognized scrub typhus endemic country. We report our experience with 189 scrub typhus patients seen at a civilian outpatient clinic in Chinhae, Republic of Korea, from 1985 through 1990, and verify the accuracy of clinical diagnosis by serologic tests.