bluuebunny/crossref_metadata_2025 huggingface dataset:
Autoregulator Protein PhaR for Biosynthesis of Polyhydroxybutyrate [P(3HB)] Possibly Has Two Separate Domains That Bind to the Target DNA and P(3HB): Functional Mapping of Amino Acid Residues Responsible for DNA Binding
Authors: Yamada Miwa , Yamashita Koichi , Wakuda Akiko , Ichimura Kazuyoshi , Maehara Akira , Maeda Michihisa , Taguchi Seiichi
Published: November 2006

PhaR from
Paracoccus denitrificans
functions as a repressor or autoregulator of the expression of genes encoding phasin protein (PhaP) and PhaR itself, both of which are components of polyhydroxyalkanoate (PHA) granules (A. Maehara, S. Taguchi, T. Nishiyama, T. Yamane, and Y. Doi, J. Bacteriol. 184:3992-4002, 2002). PhaR is a unique regulatory protein in that it also has the ability to bind tightly to an effector molecule, PHA polyester. In this study, by using a quartz crystal microbalance, we obtained direct evidence that PhaR binds to the target DNA and poly[(
R
)-3-hydroxybutyrate] [P(3HB)], one of the PHAs, at the same time. To identify the PhaR amino acid residues responsible for DNA binding, deletion and PCR-mediated random point mutation experiments were carried out with the gene encoding the PhaR protein. PhaR point mutants with decreased DNA-binding abilities were efficiently screened by an in vivo monitoring assay system coupled with gene expression of green fluorescent protein in
Escherichia coli
. DNA-binding abilities of the wild-type and mutants of recombinant PhaR expressed in
E. coli
were evaluated using a gel shift assay and a surface plasmon resonance analysis. These experiments revealed that basic amino acids and a tyrosine in the N-terminal region, which is highly conserved among PhaR homologs, are responsible for DNA binding. However, most of the mutants with decreased DNA-binding abilities were unaffected in their ability to bind P(3HB), strongly suggesting that PhaR has two separate domains capable of binding to the target DNA and P(3HB).
Role of GerD in Germination of
Bacillus subtilis
Spores
Authors: Pelczar Patricia L. , Igarashi Takao , Setlow Barbara , Setlow Peter
Published: November 2006

Spores of a
Bacillus subtilis
strain with a
gerD
deletion mutation (Δ
gerD
) responded much slower than wild-type spores to nutrient germinants, although they did ultimately germinate, outgrow, and form colonies. Spores lacking GerD and nutrient germinant receptors also germinated slowly with nutrients, as did Δ
gerD
spores in which nutrient receptors were overexpressed. The germination defect of Δ
gerD
spores was not suppressed by many changes in the sporulation or germination conditions. Germination of Δ
gerD
spores was also slower than that of wild-type spores with a pressure of 150 MPa, which triggers spore germination through nutrient receptors. Ectopic expression of
gerD
suppressed the slow germination of Δ
gerD
spores with nutrients, but overexpression of GerD did not increase rates of spore germination. Loss of GerD had no effect on spore germination induced by agents that do not act through nutrient receptors, including a 1:1 chelate of Ca
2+
and dipicolinic acid, dodecylamine, lysozyme in hypertonic medium, a pressure of 500 MPa, and spontaneous germination of spores that lack all nutrient receptors. Deletion of GerD's putative signal peptide or change of its likely diacylglycerylated cysteine residue to alanine reduced GerD function. The latter findings suggest that GerD is located in a spore membrane, most likely the inner membrane, where the nutrient receptors are located. All these data suggest that, while GerD is not essential for nutrient germination, this protein has an important role in spores' rapid response to nutrient germinants, by either direct interaction with nutrient receptors or some signal transduction essential for germination.
Comparison of Antimicrobial Susceptibility Testing of
Campylobacter
spp. by the Agar Dilution and the Agar Disk Diffusion Methods
Authors: Luangtongkum Taradon , Morishita Teresa Y. , El-Tayeb Amna B. , Ison Aaron J. , Zhang Qijing
Published: November 2006

The correlation and the level of agreement between the standardized agar dilution and the agar disk diffusion methods for antimicrobial susceptibility testing of
Campylobacter
were investigated. A high-level agreement between the two methods was evident for aminoglycosides and fluoroquinolones, while a low-level agreement was observed for other antibiotics.
Determining Human Immunodeficiency Virus Coreceptor Use in a Clinical Setting: Degree of Correlation between Two Phenotypic Assays and a Bioinformatic Model
Authors: Skrabal Katharina , Low Andrew J. , Dong Winnie , Sing Tobias , Cheung Peter K. , Mammano Fabrizio , Harrigan P. Richard
Published: November 2006

Two recombinant phenotypic assays for human immunodeficiency virus (HIV) coreceptor usage and an HIV envelope genotypic predictor were employed on a set of clinically derived HIV type 1 (HIV-1) samples in order to evaluate the concordance between measures. Previously genotyped HIV-1 samples derived from antiretroviral-naïve individuals were tested for coreceptor usage using two independent phenotyping methods. Phenotypes were determined by validated recombinant assays that incorporate either an ∼2,500-bp (“Trofile” assay) or an ∼900-bp (TRT assay) fragment of the HIV envelope gp120. Population-based HIV envelope V3 loop sequences (∼105 bp) were derived by automated sequence analysis. Genotypic coreceptor predictions were performed using a support vector machine model trained on a separate genotype-Trofile phenotype data set. HIV coreceptor usage was obtained from both phenotypic assays for 74 samples, with an overall 85.1% concordance. There was no evidence of a difference in sensitivity between the two phenotypic assays. A bioinformatic algorithm based on a support vector machine using HIV V3 genotype data was able to achieve 86.5% and 79.7% concordance with the Trofile and TRT assays, respectively, approaching the degree of agreement between the two phenotype assays. In most cases, the phenotype assays and the bioinformatic approach gave similar results. However, in cases where there were differences in the tropism results, it was not clear which of the assays was “correct.” X4 (CXCR4-using) minority species in clinically derived samples likely complicate the interpretation of both phenotypic and genotypic assessments of HIV tropism.
Prevalence and Characterization of Class I Integrons among
Pseudomonas aeruginosa
and
Acinetobacter baumannii
Isolates from Patients in Nanjing, China
Authors: Gu Bing , Tong Mingqing , Zhao Wenjun , Liu Genyan , Ning Mingzhe , Pan Shiyang , Zhao Wangsheng
Published: November 2006

Class I integrons were detected in 40.8% (40/98) of
Pseudomonas aeruginosa
strains and 52.8% (56/106) of
Acinetobacter baumannii
strains in the Nanjing area of China, including several cassette arrays not previously reported.
Molecular Epidemiology of Metallo-β-Lactamase-Producing
Pseudomonas aeruginosa
in the Calgary Health Region: Emergence of VIM-2-Producing Isolates
Authors: Pitout Johann D. D. , Chow Barbara L. , Gregson Daniel B. , Laupland Kevin B. , Elsayed Sameer , Church Deirdre L.
Published: November 2006

A study was designed to describe the molecular epidemiology of carbapenem-resistant (CR)
Pseudomonas aeruginosa
in a large well-defined geographical region with a centralized laboratory system serving one pediatric and three large adult hospitals (acute care centers I, II, and III). Molecular characterization was done using PCR with sequencing of the integron-associated gene cassettes. Pulsed-field gel electrophoresis (PFGE) using a modified combined
Stenotrophomas maltophilia
and
Streptococcus pneumoniae
protocol with SpeI was performed on CR
P. aeruginosa
strains isolated in the Calgary Health Region during 2002-2006. The majority (96%) of metallo-β-lactamase (MBL)-producing isolates produced VIM-2 with gene cassettes
aacC1
and
aacA4
, while 4% produced IMP-7 with gene cassettes
aacC4
and
aacC1
. Eighty-six percent of VIM-2 producers belonged to a cluster (MBLV) that was responsible for nosocomial outbreaks during 2003 (intensive care unit) and 2004 (bone marrow transplant unit) at acute care center I. Environmental isolates from these units also belonged to MBLV. The majority of strains from cluster MBLVR (related to MBLV) were present in acute care center III. Isolates producing IMP-7 belonged to a different cluster (MBLI) and were related to strains described during the 1990s. PFGE of the MBL-negative CR strains showed that 37% belonged to a closely related cluster, NMBL, whose members were predominantly isolated from acute care center II. Our findings suggest that CR and dissemination of MBL clusters among
P. aeruginosa
populations in large geographic healthcare regions are dynamic processes that require continuous molecular surveillance.
Outbreaks of Multidrug-Resistant
Pseudomonas aeruginosa
in Community Hospitals in Japan
Authors: Sekiguchi Jun-Ichiro , Asagi Tsukasa , Miyoshi-Akiyama Tohru , Kasai Atsushi , Mizuguchi Yukie , Araake Minako , Fujino Tomoko , Kikuchi Hideko , Sasaki Satoru , Watari Hajime , Kojima Tadashi , Miki Hiroshi , Kanemitsu Keiji , Kunishima Hiroyuki , Kikuchi Yoshihiro , Kaku Mitsuo , Yoshikura Hiroshi , Kuratsuji Tadatoshi , Kirikae Teruo
Published: November 2006

We previously reported an outbreak in a neurosurgery ward of catheter-associated urinary tract infection with multidrug-resistant (MDR)
Pseudomonas aeruginosa
strain IMCJ2.S1, carrying the 6′-
N
-aminoglycoside acetyltransferase gene [
aac(6
′
)-Iae
]. For further epidemiologic studies, 214 clinical isolates of MDR
P. aeruginosa
showing resistance to imipenem (MIC ≥ 16 μg/ml), amikacin (MIC ≥ 64 μg/ml), and ciprofloxacin (MIC ≥ 4 μg/ml) were collected from 13 hospitals in the same prefecture in Japan. We also collected 70 clinical isolates of
P. aeruginosa
that were sensitive to one or more of these antibiotics and compared their characteristics with those of the MDR
P. aeruginosa
isolates. Of the 214 MDR
P. aeruginosa
isolates, 212 (99%) were serotype O11. We developed a loop-mediated isothermal amplification (LAMP) assay and a slide agglutination test for detection of the
aac(6
′
)-Iae
gene and the AAC(6′)-Iae protein, respectively. Of the 212 MDR
P. aeruginosa
isolates, 212 (100%) and 207 (98%) were positive in the LAMP assay and in the agglutination test, respectively. Mutations of
gyrA
and
parC
genes resulting in amino acid substitutions were detected in 213 of the 214 MDR
P. aeruginosa
isolates (99%). Of the 214 MDR
P. aeruginosa
isolates, 212 showed pulsed-field gel electrophoresis patterns with ≥70% similarity to that of IMCJ2.S1 and 83 showed a pattern identical to that of IMCJ2.S1, indicating that clonal expansion of MDR
P. aeruginosa
occurred in community hospitals in this area. The methods developed in this study to detect
aac(6
′
)-Iae
were rapid and effective in diagnosing infections caused by various MDR
P. aeruginosa
clones.
Evaluation of the Sensitivities of DNA Extraction and PCR Methods for Detection of
Giardia duodenalis
in Stool Specimens
Authors: Nantavisai Kwannan , Mungthin Mathirut , Tan-ariya Peerapan , Rangsin Ram , Naaglor Tawee , Leelayoova Saovanee
Published: November 2006

Sensitivities of DNA extraction methods and PCR methods for
Giardia duodenalis
were evaluated. A combination of the most sensitive methods, i.e., FTA filter paper and a PCR protocol using RH11/RH4 and GiarF/GiarR primers, showed no significant differences compared to immunofluorescence assay in terms of their sensitivities and specificities.
Usefulness of the BACTEC MGIT 960 System for Isolation of
Mycobacterium tuberculosis
from Sputa Subjected to Long-Term Storage
Authors: Pardini Manuela , Varaine Francis , Bonnet Maryline , Orefici Graziella , Oggioni Marco Rinaldo , Fattorini Lanfranco
Published: November 2006

The recovery of
Mycobacterium tuberculosis
from sputa positive or negative for acid-fast bacilli that were stored for 17 ± 7 days and inoculated in the BACTEC MGIT 960 system (MGIT) was higher than that from sputa inoculated in Lowenstein-Jensen medium. MGIT is useful for isolation of
M. tuberculosis
from sputa subjected to long-term storage.
Rapid Detection of Point Mutations Conferring Resistance to Fluoroquinolone in
gyrA
of
Helicobacter pylori
by Allele-Specific PCR
Authors: Nishizawa Toshihiro , Suzuki Hidekazu , Umezawa Ayako , Muraoka Hiroe , Iwasaki Eisuke , Masaoka Tatsuhiro , Kobayashi Intetsu , Hibi Toshifumi
Published: November 2006

Helicobacter pylori
strains with reduced susceptibility to fluoroquinolones have a mutation at either codon 87 Asn or 91 Asp of the
gyrA
gene. A rapid test based on an allele-specific PCR (AS-PCR) was designed to detect the
gyrA
mutations. Clinical
H. pylori
isolates were obtained from the stomachs of 51 patients with
H. pylori
infections who showed treatment failure. The MICs of gatifloxacin (GAT) were determined by the agar dilution method. Identical genotyping results were obtained with AS-PCR and conventional PCR. The
gyrA
mutations of
H. pylori
causing reduced susceptibility to fluoroquinolones could be detected successfully by this method. A significant association was observed between the presence of mutations, as detected by AS-PCR, and the resistance of the strains to GAT. Moreover, genotyping by AS-PCR took less than 3 to 4 h. The AS-PCR method for the detection of
gyrA
mutations in
H. pylori
is useful for easy identification of fluoroquinolone-resistant strains of
H. pylori
.
Structural and Functional Characterization of Sapovirus RNA-Dependent RNA Polymerase
Authors: Fullerton Stephen W. B. , Blaschke Martina , Coutard Bruno , Gebhardt Julia , Gorbalenya Alexander , Canard Bruno , Tucker Paul A. , Rohayem Jacques
Published: November 2006

Sapoviruses are one of the major agents of acute gastroenteritis in childhood. They form a tight genetic cluster (genus) in the
Caliciviridae
family that regroups both animal and human pathogenic strains. No permissive tissue culture has been developed for human sapovirus, limiting its characterization to surrogate systems. We report here on the first extensive characterization of the key enzyme of replication, the RNA-dependent RNA polymerase (RdRp) associated with the 3D
pol
-like protein. Enzymatically active sapovirus 3D
pol
and its defective mutant were expressed in
Escherichia coli
and purified. The overall structure of the sapovirus 3D
pol
was determined by X-ray crystallography to 2.32-Å resolution. It revealed a right hand fold typical for template-dependent polynucleotide polymerases. The carboxyl terminus is located within the active site cleft, as observed in the RdRp of some (norovirus) but not other (lagovirus) caliciviruses. Sapovirus 3D
pol
prefers Mn
2+
over Mg
2+
but may utilize either as a cofactor in vitro. In a synthetic RNA template-dependent reaction, sapovirus 3D
pol
synthesizes a double-stranded RNA or labels the template 3′ terminus by terminal transferase activity. Initiation of RNA synthesis occurs de novo on heteropolymeric templates or in a primer-dependent manner on polyadenylated templates. Strikingly, this mode of initiation of RNA synthesis was also described for norovirus, but not for lagovirus, suggesting structural and functional homologies in the RNA-dependent RNA polymerase of human pathogenic caliciviruses. This first experimental evidence makes sapovirus 3D
pol
an attractive target for developing drugs to control calicivirus infection in humans.
Proinflammatory Cytokine Gene Induction by Human T-Cell Leukemia Virus Type 1 (HTLV-1) and HTLV-2 Tax in Primary Human Glial Cells
Authors: Banerjee Prabal , Rochford Rosemary , Antel J. , Canute G. , Wrzesinski Stephen , Sieburg Michelle , Feuer Gerold
Published: November 2006

Infection with human T-cell leukemia virus type 1 (HTLV-1) can result in the development of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a chronic inflammatory disease of the central nervous system (CNS). HTLV-2 is highly related to HTLV-1 at the genetic level and shares a high degree of sequence homology, but infection with HTLV-2 is relatively nonpathogenic compared to HTLV-1. Although the pathogenesis of HAM/TSP remains to be fully elucidated, previous evidence suggests that elevated levels of the proinflammatory cytokines in the CNS are associated with neuropathogenesis. We demonstrate that HTLV-1 infection in astrogliomas results in a robust induction of interleukin-1β (IL-1β), IL-1α, tumor necrosis factor alpha (TNF-α), TNF-β, and IL-6 expression. HTLV encodes for a viral transcriptional transactivator protein named Tax that also induces the transcription of cellular genes. To investigate and compare the effects of Tax1 and Tax2 expression on the dysregulation of proinflammatory cytokines, lentivirus vectors were used to transduce primary human astrocytomas and oligodendrogliomas. The expression of Tax1 in primary human astrocytomas and oligodendrogliomas resulted in significantly higher levels of proinflammatory cytokine gene expression compared to Tax2. Notably, Tax1 expression uniquely sensitized primary human astrocytomas to apoptosis. A Tax2/Tax1 chimera encoding the C-terminal 53 amino acids of the Tax1 fused to the Tax2 gene (Tax221) demonstrated a phenotype that resembled Tax1, with respect to proinflammatory cytokine gene expression and sensitization to apoptosis. The patterns of differential cytokine induction and sensitization to apoptosis displayed by Tax1 and Tax2 may reflect differences relating to the heightened neuropathogenicity associated with HTLV-1 infection and the development of HAM/TSP.
Mutually Exclusive T-Cell Receptor Induction and Differential Susceptibility to Human Immunodeficiency Virus Type 1 Mutational Escape Associated with a Two-Amino-Acid Difference between HLA Class I Subtypes
Authors: Yu Xu G. , Lichterfeld Mathias , Chetty Senica , Williams Katie L. , Mui Stanley K. , Miura Toshiyuki , Frahm Nicole , Feeney Margaret E. , Tang Yanhua , Pereyra Florencia , LaBute Montiago X. , Pfafferott Katja , Leslie Alisdair , Crawford Hayley , Allgaier Rachel , Hildebrand William , Kaslow Richard , Brander Christian , Allen Todd M. , Rosenberg Eric S. , Kiepiela Photini , Vajpayee Madhu , Goepfert Paul A. , Altfeld Marcus , Goulder Philip J. R. , Walker Bruce D.
Published: November 2006

The relative contributions of HLA alleles and T-cell receptors (TCRs) to the prevention of mutational viral escape are unclear. Here, we examined human immunodeficiency virus type 1 (HIV-1)-specific CD8
+
T-cell responses restricted by two closely related HLA class I alleles, B*5701 and B*5703, that differ by two amino acids but are both associated with a dominant response to the same HIV-1 Gag epitope KF11 (KAFSPEVIPMF). When this epitope is presented by HLA-B*5701, it induces a TCR repertoire that is highly conserved among individuals, cross-recognizes viral epitope variants, and is rarely associated with mutational escape. In contrast, KF11 presented by HLA-B*5703 induces an entirely different, more heterogeneous TCR β-chain repertoire that fails to recognize specific KF11 escape variants which frequently arise in clade C-infected HLA-B*5703
+
individuals. These data show the influence of HLA allele subtypes on TCR selection and indicate that extensive TCR diversity is not a prerequisite to prevention of allowable viral mutations.
Comparative Analysis of Twelve Genomes of Three Novel Group 2c and Group 2d Coronaviruses Reveals Unique Group and Subgroup Features
Authors: Woo Patrick C. Y. , Wang Ming , Lau Susanna K. P. , Xu Huifang , Poon Rosana W. S. , Guo Rongtong , Wong Beatrice H. L. , Gao Kai , Tsoi Hoi-wah , Huang Yi , Li Kenneth S. M. , Lam Carol S. F. , Chan Kwok-hung , Zheng Bo-jian , Yuen Kwok-yung
Published: November 2006

Twelve complete genomes of three novel coronaviruses—bat coronavirus HKU4 (bat-CoV HKU4), bat-CoV HKU5 (putative group 2c), and bat-CoV HKU9 (putative group 2d)—were sequenced. Comparative genome analysis showed that the various open reading frames (ORFs) of the genomes of the three coronaviruses had significantly higher amino acid identities to those of other group 2 coronaviruses than group 1 and 3 coronaviruses. Phylogenetic trees constructed using chymotrypsin-like protease, RNA-dependent RNA polymerase, helicase, spike, and nucleocapsid all showed that the group 2a and 2b and putative group 2c and 2d coronaviruses are more closely related to each other than to group 1 and 3 coronaviruses. Unique genomic features distinguishing between these four subgroups, including the number of papain-like proteases, the presence or absence of hemagglutinin esterase, small ORFs between the membrane and nucleocapsid genes and ORFs (NS7a and NS7b), bulged stem-loop and pseudoknot structures downstream of the nucleocapsid gene, transcription regulatory sequence, and ribosomal recognition signal for the envelope gene, were also observed. This is the first time that NS7a and NS7b downstream of the nucleocapsid gene has been found in a group 2 coronavirus. The high Ka/Ks ratio of NS7a and NS7b in bat-CoV HKU9 implies that these two group 2d-specific genes are under high selective pressure and hence are rapidly evolving. The four subgroups of group 2 coronaviruses probably originated from a common ancestor. Further molecular epidemiological studies on coronaviruses in the bats of other countries, as well as in other animals, and complete genome sequencing will shed more light on coronavirus diversity and their evolutionary histories.
The Construction of the BESIII Experiment
Authors: Wang Yi-Fang
Published: November 2006

BESIII is a high precision, general purpose detector for the high luminosity e+e- collider, BEPCII, running at the tau-charm energy region. Its design and current status of construction is presented.
Recent Results of D Physics on BESII
Authors:   For BES collaboration., Ma Hai Long
Published: November 2006

Based on the data sample of 33 pb-1 collected at and around 3.773 GeV with the BESII detector at the BEPC collider, the absolute branching fractions for some exclusive semileptonic decays and inclusive decays of D mesons have been measured. With the measured branching fractions, the ratio of the two partial widths of the decays D0 → K-μ+νμ and [Formula: see text] is determined to be 0.87 ± 0.24 ± 0.15, which supports that the isospin conversation holds in the exclusive semimuonic decays of D0 and D- mesons. The ratio of the vector to pseudoscalar semileptonic decay rates [Formula: see text] is determined to be 0.57 ± 0.17 ± 0.02.
Form Factors and Absolute Branching Fractions for D0 → K(π)ℓν
Authors:   BELLE Collaboration., WIDHALM LAURENZ
Published: November 2006

We present a study of D0 decaying to K-ℓ+ν and π-ℓ+ν final states using a 282 fb-1 data sample collected by the Belle experiment at the KEKB e+e- collider. The D0 flavor and momentum are tagged through a full reconstruction of the recoiling charm meson and additional mesons from fragmentation. The reconstruction method provides very good resolution in neutrino momentum and in q2 = (pℓ + pν)2. Normalizing to the total number of D0 tags, we measure the absolute branching fractions to be [Formula: see text] and [Formula: see text] and the semi-leptonic form factors (within the modified pole model) [Formula: see text] and [Formula: see text].
$D^0\mbox{-}\overline{D}^0$ Mixing Results from BABAR with D0 → K+π-π0
Authors:   For the BABAR Collaboration., Rahimi Amir M. , Wilson Michael G.
Published: November 2006

We present a preliminary search for [Formula: see text] mixing using the decays D0 → K+π-π0, additionally presenting Dalitz-plot distributions and a measurement of the branching ratio for this mode. A new tagging technique is used to produce the doubly Cabibbo-suppressed Dalitz plot, which in turn is used to motivate the method used for the D-mixing search. We analyze 230.4 fb-1 of data collected from the BABAR detector at the PEP-II collider. Assuming CP conservation, we find RM < 0.054% with 95% confidence, and we estimate that the data are consistent with no mixing at a 4.5% confidence level. We present D-mixing results both with and without the assumption of CP conservation.
Dynamically Generated Hidden-Charm Baryon Resonances
Authors: Lutz M. F. M. , Hofmann J.
Published: November 2006

Identifying a zero-range exchange of vector mesons as the driving force for the s-wave scattering of pseudo-scalar mesons off the baryon ground states, a rich spectrum of hadronic nuclei is formed. We argue that chiral symmetry and large-Nc considerations determine that part of the interaction which generates the spectrum. We suggest the existence of strongly bound crypto-exotic baryons, which contain a charm-anti-charm pair. Such states are narrow since they can decay only via OZI-violating processes.
TWO PHOTON PHYSICS AT BELLE
Authors:   For the BELLE Collaboration., Chen Augustine E.
Published: November 2006

Results of high statistic two-photon collisions at Belle are presented. Only [Formula: see text] process is included in this report, here [Formula: see text] could be π+π-, K+K-, [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] or [Formula: see text]. Measurements of [Formula: see text] for charmonia resonance states are listed. A new χ′c2 candidate in [Formula: see text] has been identified as a spin-2 (helicity-2) object. Cross section and production angle distributions are measured and compared with various QCD calculations.
$D_{sJ}^*(2317)$, $D_{J}^*(2308)$ AND $D_{sJ}^*(2632)$ AS CANDIDATES FOR OPEN-CHARM TETRAQUARKS
Authors: DMITRAŠINOVIĆ V.
Published: November 2006

We review the theoretical and experimental evidence for the candidacy of the [Formula: see text], [Formula: see text] and the [Formula: see text] for charmed tetraquarks. We briefly review the 't Hooft interaction's influence on the single-charm ( C =1)[Formula: see text] tetraquark mass spectrum: its consequences for other observed mesons such as the [Formula: see text], as well as its predictions of the (thus far) unobserved exotic tetraquark states. In particular we show that the near mass degeneracy of [Formula: see text] and [Formula: see text] was naturally predicted by the tetraquark model with 't Hooft interaction, and thus may constitute the first "smoking gun" evidence for tetraquark existence. A short outlook of possible future research directions is given.
RECENT RESULTS OF ψ′ DECAY AT BESII
Authors: MO XIAO-HU
Published: November 2006

Based on 14 M ψ′ events, systematic studies have been make for hadronic decays, which are conerned with 12% rule test, phase analysis and form factor measurement. All these studies are helpful for understanding the decay dynamics in charmonium region.
FORMATION AND HARD MAGNETIC PROPERTIES OF A HEXAGONAL NETWORK OF NICKEL FERRITE NANOPARTICLES
Authors: CHEN JIAFU , YE YU , CHEN QIANWANG
Published: November 2006

A novel hexagonal network structure formed by self-assembly of discrete nickel ferrite nanoparticles on a carbon-coated Cu grid is reported. Each hexagon consists of about 22 discrete nanoparticles with sizes from 120 to 250 nm. The side of the regular hexagon contains 4–6 discrete nanoparticles. The sample displays a large coercivity of 622.6 Oe, exhibiting a hard magnetic feature different from those of the corresponding bulk materials, and is closely related to the hexagonal network structure of nickel ferrite nanoparticles.
AN ADAPTIVE OBSERVER FOR CHAOS SYNCHRONIZATION OF A NONLINEAR ELECTRONIC CIRCUIT
Authors: FOTSIN HILAIRE , KAKMENI F. M. MOUKAM , BOWONG SAMUEL
Published: November 2006

This Letter studies adaptive chaos synchronization between two coupled nonlinear electrical circuits using a linear state feedback. A simple and yet easily applicable algorithm is derived for adaptive chaos synchronization based on the Lyapunov stability theory. An adaptive linear state feedback is derived such that the coupled systems are globally synchronized. Numerical simulations show the effectiveness of the proposed synchronization scheme. A Pspice simulation of the adaptive synchronization process is performed to confirm the numerical results.
LIFETIME MEASUREMENTS IN 134Pr AND CHIRALITY IN NUCLEI
Authors: TONEV D. , PETKOV P. , BALABANSKI D. L. , DE ANGELIS G. , GADEA A. , NAPOLI D. R. , MARGINEAN N. , DEWALD A. , PEJOVIC P. , FITZLER A. , MÖLLER O. , ZELL K. O. , BRANT S. , FRAUENDORF S. , BAZZACCO D. , LENZI S. , LUNARDI S. , BEDNARCZYK P. , CURIEN D. , PETRACHE C. , ZHONG Q. , ZHANG Y. H. , ZHANG JING-YE
Published: November 2006

Lifetimes of exited states in 134 Pr were measured be means of the recoil distance Doppler-shift and Doppler-shift attenuation techniques. The experiments were performed at IReS, Strasbourg using the EUROBALL IV spectrometer, in conjunction with the inner BGO ball and the Cologne coincidence plunger apparatus. Exited states in 134 Pr were populated in the fusion-evaporation reaction 119 Sn (19 F , 4 n )134 Pr . Reduced transition probabilities in 134 Pr are compared to the predictions of the two quasiparticle+triaxial rotor and interacting boson fermion-fermion models. The experimental results do not support the presence of static chirality in 134 Pr underlying the importance of shape fluctuations. Only within a dynamical context the presence of intrinsic chirality in 134 Pr can be supported.
SPECTROSCOPY ON UNSTABLE NUCLEI AT RIKEN
Authors: SAKURAI HIROYOSHI
Published: November 2006

Recent studies on nuclear structure by using radioactive isotope beams available at the RIKEN projectile-fragment separator (RIPS) are introduced. Special emphasis is given to experiments selected from recent programs that highlight studies; anomalous quadrupole natures in 16 C , new results on 28 Ne with respect to the island-of-inversion region. Experimental programs at the new facility called RIBF are also introduced.
STUDY OF LIGHT UNSTABLE NUCLEI VIA DIRECT NUCLEAR REACTIONS
Authors: YE YANLIN , PANG DANYANG , ZHANG CENG , JIANG DONGXING , ZHENG TAO , LI ZHIHUAN , LI XIANGQING , GE YUCHENG , HUA HUI , WU CUIE , LI CHEN , LOU JIANLING
Published: November 2006

Sensitivity of the direct nuclear reaction to the exotic structure of the unstable nuclei is outlined. The transfer reaction induced by 6 He on a 9 Be target at 25 MeV/u is described. The theoretical analysis using CRC model supports the di-neutron configuration of the two valence neutrons in 6 He . Preliminary calculation for 17 Ne were introduced which indicates the advantage of using transfer reaction to clarify the s-wave or d-wave configuration of the valence protons.
CLUSTER ASPECT IN UNSTABLE NUCLEI IN P-SHELL AND SD-SHELL REGIONS
Authors: KANADA-EN'YO YOSHIKO , KIMURA MASAAKI
Published: November 2006

Structures of excited states in 11 C and 11 B were studied based on variational calculations after spin-parity projection in a framework of antisymmetrized molecular dynamics (AMD). The calculations systematically reproduce the experimental data of the transition strengths such as Gamov-Teller and M1 transitions. A well-developed cluster structure of 2α+3 He (t) was found in the [Formula: see text] state of 11 C (11 B ), which can be assigned to the observed [Formula: see text] state at 8 MeV. The calculations reproduce the small [Formula: see text] measured in the recent experiments. It was suggested that the [Formula: see text] state has a dilute cluster state, and its features are similar to those of the [Formula: see text] which is considered to be a gas state of three α clusters. The structures of 13 C were also discussed.
SUPERHEAVY ELEMENTS — SYNTHESIS, STRUCTURE AND REACTION MECHANISM
Authors: ACKERMANN DIETER
Published: November 2006

The elements with Z = 107 - 112 have been successfully synthesized at GSI employing 208 Pb and 209 Bi targets and producing relatively cold compound systems. The unambiguous identification of these elements via evaporation residue(ER)-α correlations and the link to known α emitters has been confirmed by independent measurements performed at RIKEN, Japan and partly by chemistry experiments. An impressive body of data which is interpreted as the synthesis of isotopes with Z = 114 - 116 and 118 has been accumulated at the FLNR, Dubna, where the alternative approach of reactions with actinoide targets forming more excited compound nuclei was pursued. Despite of a consistent systematic picture, the final confirmation, however, is still missing. These exciting results together with the possibilities opened up by the advanced experimental techniques and the nowadays available beam intensities with their expected future increase have triggered a broad range of activities. Apart from experiments to attempt the synthesis of new elements, nuclear structure investigations in the transactinoide region has become possible for Z up to 108 or 110. Heavy element chemistry has successfully placed Hs in the periodic table and is now attacking element 112. The development of accelerators and experimental methods promises advances to enable the extension of these investigations in regions closer to the "island of stability". Mass measurements using ion traps and neutron rich unstable beam species for the systematic investigation of nuclear structure and reaction mechanisms for heavy neutron rich systems are believed to complete the variety of tools in future.
K = 6+ ISOMERS IN Hf, Yb AND W NUCLEI
Authors: RATH ASWINI KUMAR , WALKER P. M. , PRAHARAJ C. R. , XU F. R.
Published: November 2006

Using deformed Hartree-Fock and angular momentum projection (PHF) technique we try to understand the intrinsic structure and the systematics in the life times of K = 6+ isomers in the Hf isotopes (in 172-178 Hf nuclei) and N = 104 Yb , Hf and W isotones. The band structure in 172 Hf is reasonably well reproduced. The variation in the B ( E 2;2+ → 0+) values in the Hf isotopes as well as N = 104 isotones are well reproduced. The calculated K -forbidden E2 transition probabilities from the isomer bandheads to the 4+ yrast states qualitatively explain the variation of the lifetimes with N and Z .
ISOMER BEAMS
Authors: WALKER P. M.
Published: November 2006

As a subset of radioactive beams, isomer beams open up the dimensions of excitation energy and angular momentum. The problem of isomer decay rates is briefly presented, as they are not yet well understood. The use of isomer beams for nuclear structure investigations is reviewed, using examples related to exotic decay modes, charge radii, and Coulomb excitation. There are also unique possibilities for the study of induced electromagnetic depopulation. A key aspect is beam purification, for which different techniques are discussed.
CHARACTERIZATION OF POLY(ACRYLIC ACID) DIFFUSION DYNAMICS ON THE GRAFTED SURFACE OF POLY(ETHYLENE TEREPHTHALATE) FILMS BY FLUORESCENCE CORRELATION SPECTROSCOPY
Authors: PAN XIAOTAO , AW CAILI , DU YANAN , YU HANRY , WOHLAND THORSTEN
Published: November 2006

Poly(acrylic acid) (PAAc) is a commonly used polymer grafted on poly(ethylene terephthalate) films for the immobilization of bioactive molecules that directly interact with living cells or tissues for the maintenance of their viability and functionality. The diffusion property of the grafted PAAc on the surface is a critical parameter related to the density, length of polymer chains, and ionic strength of the solution. Fluorescence correlation spectroscopy (FCS) is able to measure the diffusion coefficient of fluorescent particles in solution with single molecule sensitivity and specificity. It was used as an effective tool to detect diffusion dynamics of Atto 565 molecules, a good indicator for viscosity of PAAc, in both aqueous polymer solutions and polymer grafted film surfaces immersed in solution. In this work we determine the polymer chain length under different polymerization conditions in solution and deduce the solution viscosity by FCS measurements of Atto 565 as tracer molecule. By using the same tracer on the grafted polymer films we can infer the viscosity of these grafted layers under a variety of conditions, including the PAAc chain length, the UV exposure time during polymerization, the ionic strength, and the pH value of the immersed solution.
QUANTITATIVE STUDIES OF SUBDIFFUSION IN LIVING CELLS AND ACTIN NETWORKS
Authors: MUNTEANU EMILIA-LAURA , OLSEN ANJA LEA , TOLIC-NØRRELYKKE IVA , FLYVBJERG HENRIK , ODDERSHEDE LENE , BERG-SØRENSEN KIRSTINE
Published: November 2006

Optical tweezers are a versatile tool in biophysics and have matured from a tool of manipulation to a tool of precise measurements. We argue here that the data analysis with advantage can be developed to a level of sophistication that matches that of the instrument. We review methods of analysis of optical tweezers data, primarily based on the power spectra of time series of positions for trapped spherical objects. The majority of precise studies in the literature are performed on in vitro systems, whereas in the present work, an example of an in vivo system is presented for which precise power spectral analysis is both useful and necessary. The biological system is the cytoplasm of fission yeast, Schizosaccharomyces pombe in which we observe subdiffusion of lipid granules. In a search for the cause of subdiffusion, we chemically disrupt the actin network in the cytoplasm and further consider in vitro networks of filamenteous actin undergoing similar chemical disruption.
Inhibitory role of Src family tyrosine kinases on Ca2+-dependent insulin release
Authors: Cheng Haiying , Straub Susanne G. , Sharp Geoffrey W. G.
Published: November 2006

Both neurotransmitter release and insulin secretion occur via regulated exocytosis and share a variety of similar regulatory mechanisms. It has been suggested that Src family tyrosine kinases inhibit neurotransmitter release from neuronal cells (H. Ohnishi, S. Yamamori, K. Ono, K. Aoyagi, S. Kondo, and M. Takahashi. Proc Natl Acad Sci USA 98: 10930–10935, 2001). Thus the potential role of Src family kinases in the regulation of insulin secretion was investigated in this study. Two structurally different inhibitors of Src family kinases, SU-6656 and PP2, but not the inactive compound, PP3, enhanced Ca2+-induced insulin secretion in both rat pancreatic islets and INS-1 cells in a concentration-dependent and time-dependent manner. Furthermore, Src family kinase-mediated insulin secretion appears to be dependent on elevated intracellular Ca2+and independent of glucose metabolism, the ATP-dependent K+channel, adenylyl cyclase, classical PKC isoforms, extracellular signal-regulated kinase 1/2, and insulin synthesis. The sites of action for Src family kinases seem to be distal to the elevation of intracellular Ca2+level. These results indicate that one or more Src family tyrosine kinases exert a tonic inhibitory role on Ca2+-dependent insulin secretion.
Effects of leptin replacement on hypothalamic-pituitary growth hormone axis function and circulating ghrelin levels in ob/ob mice
Authors: Luque Raul M. , Huang Zhi H. , Shah Bhumik , Mazzone Theodore , Kineman Rhonda D.
Published: November 2006

Leptin-deficient obese mice ( ob/ob) have decreased circulating growth hormone (GH) and pituitary GH and ghrelin receptor (GHS-R) mRNA levels, whereas hypothalamic GH-releasing hormone (GHRH) and somatostatin (SST) expression do not differ from lean controls. Given the fact that GH is suppressed in diet-induced obesity (a state of hyperleptinemia), it remains to be determined whether the absence of leptin contributes to changes in the GH axis of ob/ob mice. Therefore, to study the impact of leptin replacement on the hypothalamic-pituitary GH axis of ob/ob mice, leptin was infused for 7 days (sc), resulting in circulating leptin levels that were similar to wild-type controls (∼1 ng/ml). Leptin treatment reduced food intake, body weight, and circulating insulin while elevating circulating n-octanoyl ghrelin concentrations. Leptin treatment did not alter hypothalamic GHRH, SST, or GHS-R mRNA levels compared with vehicle-treated controls. However, leptin significantly increased pituitary GH and GHRH-R expression and tended to enhance circulating GH levels, but this latter effect did not reach statistical significance. In vitro, leptin (1 ng/ml, 24 h) did not affect pituitary GH, GHRH-R, or GHS-R mRNA but did enhance GH release. The in vivo effects of leptin on circulating hormone and pituitary mRNA levels were not replicated by pair feeding ob/ob mice to match the food intake of leptin-treated mice. However, leptin did prevent the fall in hypothalamic GHRH mRNA and circulating IGF-I levels observed in pair-fed mice. These results demonstrate that leptin replacement has positive effects on multiple levels of GH axis function in ob/ob mice.
Progesterone acutely increases LH pulse amplitude but does not acutely influence nocturnal LH pulse frequency slowing during the late follicular phase in women
Authors: McCartney Christopher R. , Blank Susan K. , Marshall John C.
Published: November 2006

Progesterone (P) is the primary effector of LH (and by inference gonadotropin-releasing hormone) pulse frequency slowing in cycling women, but the time course of this action is unclear. We hypothesized that P administration to estradiol (E2)-pretreated women would slow LH pulse frequency within 12 h. We studied eight normally cycling women in two separate cycles (follicular phase, cycle days 7–11). After 3 days of E2pretreatment (0.2 mg/day via transdermal patches), a 25-h blood sampling protocol (starting at 0800) was performed to define LH pulsatility. Oral micronized P (100 mg) or placebo (PBO) was administered at 1800 in a randomized, double-blind fashion, with treatment crossover occurring during a subsequent cycle. The 10-h mean P concentration increased from 0.6 ± 0.1 ng/ml before P (0800–1800) to 3.9 ± 0.3 ng/ml after P administration (2200–0800, P < 0.01). Ten-hour mean LH interpulse interval increased significantly after both P and PBO administration, with no significant difference between P and PBO. In contrast, mean LH, LH amplitude, and mean FSH increased significantly within 4 h of P administration, but not after PBO. We conclude that, in E2-pretreated women in the late follicular phase, 1) nocturnal LH pulse frequency is not acutely (within 12 h) influenced by P administration; 2) an acute increase in P causes pronounced augmentation of gonadotropin pulse amplitude within 4 h; and 3) LH pulse frequency slows overnight during the second half of the follicular phase.
Impact of proestrous milieu on expression of orexin receptors and prepro-orexin in rat hypothalamus and hypophysis: actions of Cetrorelix and Nembutal
Authors: Silveyra Patricia , Catalano Paolo N. , Lux-Lantos Victoria , Libertun Carlos
Published: November 2006

Orexins and their receptors OX1 and OX2 regulate energy balance and the sleep-wake cycle. We studied the expression of prepro-orexin (PPO), OX1, and OX2 in brain and pituitary under the influence of the hormonal status in adult rats. Primarily, PPO, OX1, and OX2 expression was determined in Sprague-Dawley female cycling rats during proestrus and in males. Animals were killed at 2-h intervals. Anterior (AH) and mediobasal (MBH) hypothalamus, anterior pituitary (P), and frontoparietal cortex (CC) were homogenized in TRIzol, and mRNAs were obtained for screening of PPO, OX1, OX2 expression by semiquantitative RT-PCR. Main findings were confirmed and extended to all days of the cycle by quantitative real-time RT-PCR. Hormones and food consumption were determined. Finally, OX1, OX2, and PPO were measured by real-time RT-PCR in tissues collected at 1900 of proestrus after treatments at 1400 with ovulation-blocking agents Cetrorelix or pentobarbital. OX1 and OX2 expression increased at least threefold in AH, MBH, and P, but not in CC, between 1700 and 2300 of proestrus, without variations in estrus, diestrus, or in males. PPO in AH and MBH showed a fourfold or higher increase only during proestrus afternoon. Cetrorelix or pentobarbital prevented increases of OX1 and OX2 only in the pituitary and blunted gonadotropin surges, but left OX1, OX2, and PPO brain expression unchanged. Reproduction, energy balance, and sleep-wake cycle are integrated. Here, we demonstrate that, in the physiological neuroendocrine condition leading to ovulation, information to the orexinergic system acts in hypothalamus and pituitary by different mechanisms.
Glucose-induced release of nitric oxide from mouse pancreatic islets as detected with nitric oxide-selective glass microelectrodes
Authors: Nunemaker Craig S. , Buerk Donald G. , Zhang Min , Satin Leslie S.
Published: November 2006

Nitric oxide (NO) is believed to play an important role in pancreatic islet physiology and pathophysiology. Research in this area has been hampered, however, by the use of indirect methods to measure islet NO. To investigate the role of NO in islet function, we positioned NO-sensitive, recessed-tip microelectrodes in close proximity to individual islets and monitored oxidation current to detect subnanomolar NO in the bath. NO release from islets consisted of a series of rapid bursts lasting several seconds and/or slow oscillations with a period of ∼100–300 s. Average baseline NO near the islets in 2.8 mM glucose was 524 ± 59 nM ( n = 12). Raising glucose from 2.8 to 11.1 mM augmented NO release by 429 ± 133 nM ( n = 12, P < 0.05), an effect blocked by the NO synthase inhibitor l-NAME ( n = 3). We also observed that glucose-stimulated increases in NO release were contemporaneous with changes in NAD(P)H and O2but occurred well before increases in calcium associated with glucose-stimulated insulin secretion. In summary, we demonstrate that NO release from islets is oscillatory and rapidly augmented by glucose, suggesting that NO release occurs early following an increase in glucose metabolism and may contribute to the stimulated insulin secretion triggered by suprathreshold glucose.
Reduction ofO-GlcNAc protein modification does not prevent insulin resistance in 3T3-L1 adipocytes
Authors: Robinson Katherine A. , Ball Lauren E. , Buse Maria G.
Published: November 2006

3T3-L1 adipocytes develop insulin-resistant glucose transport upon preincubation with high (25 mM) glucose, provided that insulin (0.6 nM) is included, Akt activation is impaired, and high glucose and insulin act synergistically. Considerable evidence suggests that increased glucose flux via the hexosamine biosynthesis pathway enhances the O-GlcNAc modification ( O-GlcNAcylation) of some critical protein(s) that may contribute to insulin resistance. However, whether enhanced protein O-GlcNAcylation is necessary for the development of insulin resistance is unknown. We used two strategies to test this hypothesis. The first strategy was the overexpression of O-GlcNAcase, which removes O-GlcNAc from Ser/Thr of proteins. Cells were infected with O-GlcNAcase-expressing adenovirus (or empty virus) 5 days before they were submitted to protocols that elicit (or not) insulin resistance. O-GlcNAcase was highly expressed and functional as assessed by Western blot, O-GlcNAcase assay, and marked reduction of O-GlcNAcylated proteins. The activity was mainly cytosolic. The second strategy was the expression of O-GlcNAc transferase (OGT) being markedly reduced by transfection of OGT siRNA, resulting in an approximately 90% decrease of nuclear and cytosolic OGT protein expression and similar reduction in O-GlcNAcylated proteins. Nontargeting siRNA had no effect. Preincubation in high glucose with low-dose insulin decreased the acute insulin response of glucose transport by at least 50% and impaired Akt activation. None of these parameters were affected by overexpression of O-GlcNAcase or by OGT knockout. Excess O-GlcNAcylation is one of many factors that can cause insulin resistance. It does not seem to be required for the development of glucose/insulin-induced insulin resistance of glucose transport and Akt activation in 3T3-L1 adipocytes.