bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Location Choices of Multinational Firms: The Role of Internationalisation Experience and Group Affiliation
Authors: Gazaniol Alexandre 
Published: May 2014

AbstractThis paper investigates whether location choices of multinational firms depend on their past export, import or Foreign Direct Investment (FDI) experience on foreign markets or the experience of other affiliated firms. Regardless of locations' characteristics, we find that exporting in a given country, and to a smaller extent importing from it, significantly increases the probability of investing in that particular country the following year. This preliminary exporting phase appears more important for firsttime investors. Moreover, location choices not only depend on the investor's own international experience, but also on the international experience of other affiliated firms: firms tend to invest in countries where the group already exports or owns a local affiliate. These last findings suggest the existence of coordinated strategies and/or information sharing between affiliated firms.
Limited and Localized Outbreak of Newly Emergent Type 2 Vaccine-Derived Poliovirus in Sichuan, China
Authors: Yan Dongmei , Zhang Yong , Zhu Shuangli , Chen Na , Li Xiaolei , Wang Dongyan , Ma Xiaozhen , Zhu Hui , Tong Wenbin , Xu Wenbo 
Published: May 2014

ABSTRACTFrom August 2011 to February 2012, an outbreak caused by type 2 circulating vaccine-derived poliovirus (cVDPV) occurred in Aba County, Sichuan, China. During the outbreak, four type 2 VDPVs (≥0.6% nucleotide divergence in theVP1region relative to the Sabin 2 strain) were isolated from 3 patients with acute flaccid paralysis (AFP) and one close contact. In addition, a type 2 pre-VDPV (0.3% to 0.5% divergence from Sabin 2) that was genetically related to these type 2 VDPVs was isolated from another AFP patient. These 4 patients were all unimmunized children 0.7 to 1.1 years old. Nucleotide sequencing revealed that the 4 VDPV isolates differed from Sabin 2 by 0.7% to 1.2% in nucleotides in theVP1region and shared 5 nucleotide substitutions with the pre-VDPV. All 5 isolates were closely related, and all were S2/S3/S2/S3 recombinants sharing common recombination crossover sites. Although the two major determinants of attenuation and temperature sensitivity phenotype of Sabin 2 (A481in the 5′ untranslated region and Ile143in theVP1protein) had reverted in all 5 isolates, one VDPV (strain CHN16017) still retained the temperature sensitivity phenotype. Phylogenetic analysis of the third coding position of the completeP1coding region suggested that the cVDPVs circulated locally for about 7 months following the initiating oral poliovirus vaccine (OPV) dose. Our findings reinforce the point that cVDPVs can emerge and spread in isolated communities with immunity gaps and highlight the emergence risks of type 2 cVDPVs accompanying the trivalent OPV used. To solve this issue, it is recommended that type 2 OPV be removed from the trivalent OPV or that inactivated polio vaccine (IPV) be used instead.
Desulfovibrio legallii Prosthetic Shoulder Joint Infection and Review of Antimicrobial Susceptibility and Clinical Characteristics of Desulfovibrio Infections
Authors: Vasoo Shawn , Mason Erin L. , Gustafson Daniel R. , Cunningham Scott A. , Cole Nicolynn C. , Vetter Emily A. , Steinmann Scott P. , Wilson Walter R. , Patel Robin , Berbari Elie F. , Henry Nancy K. 
Published: May 2014

ABSTRACT

We describe a case of shoulder hemiarthroplasty infection with
Desulfovibrio legallii
. Antimicrobial susceptibilities of 36
Desulfovibrio
isolates are presented. Metronidazole and carbapenems exhibited reliable activity, although piperacillin-tazobactam did not. Eleven previous cases of
Desulfovibrio
infection are reviewed; most arose from a gastrointestinal tract-related source.
Genomic Variation between Campylobacter jejuni Isolates Associated with Milk-Borne-Disease Outbreaks
Authors: Revez Joana , Zhang Ji , Schott Thomas , Kivistö Rauni , Rossi Mirko , Hänninen Marja-Liisa 
Published: May 2014

ABSTRACT

Bacterial genome sequencing has led to the development of new approaches for the analysis of food-borne epidemics and the exploration of the relatedness of outbreak-associated isolates and their separation from nonassociated isolates. Using Illumina technology, we sequenced a total of six isolates (two from patients, two from raw bulk milk, and two from dairy cattle) associated with a milk-borne
Campylobacter jejuni
outbreak in a farming family and compared their genomes. These isolates had identical pulsed-field gel electrophoresis (PFGE) types, and their multilocus sequence typing (MLST) type was ST-50. We used the Ma_1 isolate (milk) as the reference, and its genome was assembled and tentatively ordered using the
C. jejuni
NCTC 11168 genome as the scaffold. Using whole-genome MLST (wgMLST), we identified a total of three single-nucleotide polymorphisms (SNPs) and differences in poly(G or C) or poly(A or T) tracts in 12 loci among the isolates. Several new alleles not present in the database were detected. In contrast, the sequences of the unassociated
C. jejuni
strains P14 and 1–12S (both ST-50) differed by 420 to 454 alleles from the epidemic-associated isolates. We found that the fecal contamination of bulk tank milk occurred by highly related sequence variants of
C. jejuni
, which are reflected as SNPs and differences in the length of the poly(A or T) tracts. Poly(G or C) tracts are reversibly variable and are thus unstable markers for comparison. Further, unrelated strains of ST-50 were clearly separated from the outbreak-associated isolates, indicating that wgMLST is an excellent tool for analysis. In addition, other useful data related to the genes and genetic systems of the isolates were obtained.
Comparative Mycobacterium tuberculosis Spoligotype Distribution in Mexico
Authors: Vera-Cabrera Lucio , Ramos-Alvarez Jessica , Molina-Torres Carmen A. , Rivera-Morales Lydia Guadalupe , Rendón Adrian , Quiñones-Falconi Francisco , Ocampo-Candiani Jorge 
Published: May 2014

ABSTRACT

In the present work, we studied the genetic diversity of
Mycobacterium tuberculosis
clinical isolates from patients according to their gender, age, and geographic location in Mexico. We did not observe any statistically significant differences in regard to age or gender. We found that spoligo international type 53 (SIT53) is more frequent in the northern states and that SIT119 predominates in central Mexico.
E1-Mediated Recruitment of a UAF1-USP Deubiquitinase Complex Facilitates Human Papillomavirus DNA Replication
Authors: Lehoux Michaël , Gagnon David , Archambault Jacques 
Published: May 2014

ABSTRACT
The human papillomavirus (HPV) E1 helicase promotes viral DNA replication through its DNA unwinding activity and association with host factors. The E1 proteins from anogenital HPV types interact with the cellular WD repeat-containing factor UAF1 (formerly known as p80). Specific amino acid substitutions in E1 that impair this interaction inhibit maintenance of the viral episome in immortalized keratinocytes and reduce viral DNA replication by up to 70% in transient assays. In this study, we determined by affinity purification of UAF1 that it interacts with three deubiquitinating enzymes in C33A cervical carcinoma cells: USP1, a nuclear protein, and the two cytoplasmic enzymes USP12 and USP46. Coimmunoprecipitation experiments indicated that E1 assembles into a ternary complex with UAF1 and any one of these three USPs. Moreover, expression of E1 leads to a redistribution of USP12 and USP46 from the cytoplasm to the nucleus. Chromatin immunoprecipitation studies further revealed that E1 recruits these threes USPs to the viral origin in association with UAF1. The function of USP1, USP12, and USP46 in viral DNA replication was investigated by overproduction of catalytically inactive versions of these enzymes in transient assays. All three dominant negative USPs reduced HPV31 DNA replication by up to 60%, an effect that was specific, as it was not observed in assays performed with a truncated E1 lacking the UAF1-binding domain or with bovine papillomavirus 1 E1, which does not bind UAF1. These results highlight the importance of the USP1, USP12, and USP46 deubiquitinating enzymes in anogenital HPV DNA replication.

IMPORTANCE
Human papillomaviruses are small DNA tumor viruses that induce benign and malignant lesions of the skin and mucosa. HPV types that infect the anogenital tract are the etiological agents of cervical cancer, the majority of anal cancers, and a growing proportion of head-and-neck cancers. Replication of the HPV genome requires the viral protein E1, a DNA helicase that also interacts with host factors to promote viral DNA synthesis. We previously reported that the E1 helicase from anogenital HPV types associates with the WD40 repeat-containing protein UAF1. Here, we show that UAF1 bridges the interaction of E1 with three deubiquitinating enzymes, USP1, USP12, and USP46. We further show that these deubiquitinases are recruited by E1/UAF1 to the viral origin of DNA replication and that overexpression of catalytically inactive versions of these enzymes reduces viral DNA replication. These results highlight the need for an E1-associated deubiquitinase activity in anogenital HPV genome replication.
Human Immunodeficiency Virus Reverse Transcriptase Displays Dramatically Higher Fidelity under Physiological Magnesium Conditions
In Vitro
Authors: Achuthan Vasudevan , Keith Brian J. , Connolly Bernard A. , DeStefano Jeffrey J. 
Published: May 2014

ABSTRACT

The fidelity of human immunodeficiency virus (HIV) reverse transcriptase (RT) has been a subject of intensive investigation. The mutation frequencies for the purified enzyme
in vitro
vary widely but are typically in the 10
−4
range (per nucleotide addition), making the enzyme severalfold less accurate than most polymerases, including other RTs. This has often been cited as a factor in HIV's accelerated generation of genetic diversity. However, cellular experiments suggest that HIV does not have significantly lower fidelity than other retroviruses and shows a mutation frequency in the 10
−5
range. In this report, we reconcile, at least in part, these discrepancies by showing that HIV RT fidelity
in vitro
is in the same range as cellular results from experiments conducted with physiological (for lymphocytes) concentrations of free Mg
2+
(∼0.25 mM) and is comparable to Moloney murine leukemia virus (MuLV) RT fidelity. The physiological conditions produced mutation rates that were 5 to 10 times lower than those obtained under typically employed
in vitro
conditions optimized for RT activity (5 to 10 mM Mg
2+
). These results were consistent in both commonly used
lacZ
α complementation and steady-state fidelity assays. Interestingly, although HIV RT showed severalfold-lower fidelity under high-Mg
2+
(6 mM) conditions, MuLV RT fidelity was insensitive to Mg
2+
. Overall, the results indicate that the fidelity of HIV replication in cells is compatible with findings of experiments carried out
in vitro
with purified HIV RT, providing more physiological conditions are used.

IMPORTANCE
Human immunodeficiency virus rapidly evolves through the generation and subsequent selection of mutants that can circumvent the immune response and escape drug therapy. This process is fueled, in part, by the presumably highly error-prone HIV polymerase reverse transcriptase (RT). Paradoxically, results of studies examining HIV replication in cells indicate an error frequency that is ∼10 times lower than the rate for RT in the test tube, which invokes the possibility of factors that make RT more accurate in cells. This study brings the cellular and test tube results in closer agreement by showing that HIV RT is not more error prone than other RTs and, when assayed under physiological magnesium conditions, has a much lower error rate than in typical assays conducted using conditions optimized for enzyme activity.
Accelerated, Spleen-Based Titration of Variant Creutzfeldt-Jakob Disease Infectivity in Transgenic Mice Expressing Human Prion Protein with Sensitivity Comparable to That of Survival Time Bioassay
Authors: Halliez Sophie , Reine Fabienne , Herzog Laetitia , Jaumain Emilie , Haïk Stéphane , Rezaei Human , Vilotte Jean-Luc , Laude Hubert , Béringue Vincent 
Published: May 2014

ABSTRACT
The dietary exposure of the human population to the prions responsible for the bovine spongiform encephalopathy (BSE) epizooty has led to the emergence of variant Creutzfeldt-Jakob disease (vCJD). This fatal, untreatable neurodegenerative disorder is a growing public health concern because the prevalence of the infection seems much greater than the disease incidence and because secondary transmission of vCJD by blood transfusion or use of blood products has occurred. A current limitation in variant CJD risk assessment is the lack of quantitative information on the infectivity of contaminated tissues. To address this limitation, we tested the potential of a transgenic mouse line overexpressing human prion protein (PrP), which was previously reported to propagate vCJD prions. Endpoint titration of vCJD infectivity in different tissues was evaluated by two different methods: (i) the “classical” bioassay, based on the appearance of clinical symptoms and the detection of pathological prion protein in tissues of the inoculated mouse, and (ii) a shortened bioassay based on the detection of the protein in the mouse spleen at defined time points. The two methods proved equally sensitive in quantifying infectivity, even after very-low-dose inoculation of infected material, but the time schedule was shortened from ∼2.5 years to ∼1 year with the spleen bioassay. Compared to the “gold-standard” RIII model routinely used for endpoint titration of vCJD/BSE prions, either method improved the sensitivity by >2 orders of magnitude and allowed reevaluating the infectious titer of spleen from a vCJD individual at disease end stage to >1,000-fold-higher values.

IMPORTANCE
Here, we provide key reevaluation of the infectious titer of variant CJD brain and spleen tissues. The highly sensitive, accelerated spleen-based assay should thus constitute a key advance for variant CJD epidemiological and risk assessment purposes and should greatly facilitate future titration studies, including, for example, those aimed at validating decontamination procedures. The overlooked notion that the lymphoid tissue exhibits a higher capacity than the brain to replicate prions even after low-dose infection raises new questions about the molecular and/or cellular determinant(s) involved, a key issue regarding potent silent carriers of variant CJD in the lymphoid tissue.
Genus Beta Human Papillomavirus E6 Proteins Vary in Their Effects on the Transactivation of p53 Target Genes
Authors: White Elizabeth A. , Walther Johanna , Javanbakht Hassan , Howley Peter M. 
Published: May 2014

ABSTRACTThe genus beta human papillomaviruses (beta HPVs) cause cutaneous lesions and are thought to be involved in the initiation of some nonmelanoma skin cancers (NMSCs), particularly in patients with the genetic disorder epidermodysplasia verruciformis (EV). We have previously reported that at least two of the genus beta HPV E6 proteins bind to and/or increase the steady-state levels of p53 in squamous epithelial cells. This is in contrast to a well-characterized ability of the E6 proteins of cancer-associated HPVs of genus alpha HPV, which inactivate p53 by targeting its ubiquitin-mediated proteolysis. In this study, we have investigated the ability of genus beta E6 proteins from eight different HPV types to block the transactivation of p53 target genes following DNA damage. We find that the E6 proteins from diverse beta HPV species and types vary in their capacity to block the induction of MDM2, p21, and proapoptotic genes after genotoxic stress. We conclude that some genus beta HPV E6 proteins inhibit at least some p53 target genes, although perhaps not by the same mechanism or to the same degree as the high-risk genus alpha HPV E6 proteins.IMPORTANCEThis study addresses the ability of various human papillomavirus E6 proteins to block the activation of p53-responsive cellular genes following DNA damage in human keratinocytes, the normal host cell for HPVs. The E6 proteins encoded by the high-risk, cancer-associated HPV types of genus alpha HPV have a well-established activity to target p53 degradation and thereby inhibit the response to DNA damage. In this study, we have investigated the ability of genus beta HPV E6 proteins from eight different HPV types to block the ability of p53 to transactivate downstream genes following DNA damage. We find that some, but not all, genus beta HPV E6 proteins can block the transactivation of some p53 target genes. This differential response to DNA damage furthers the understanding of cutaneous HPV biology and may help to explain the potential connection between some beta HPVs and cancer.
Interaction of Kaposi's Sarcoma-Associated Herpesvirus ORF6 Protein with Single-Stranded DNA
Authors: Ozgur Sezgin , Griffith Jack 
Published: May 2014

ABSTRACT

Kaposi's sarcoma-associated herpesvirus (KSHV) ORF6 is homologous to the herpes simplex virus 1 (HSV-1) ICP8 and Epstein-Barr virus (EBV) BALF2 proteins. Here, we describe its single-stranded DNA (ssDNA) binding properties. Based on previous findings with ICP8 and BALF2, a 60-amino-acid C-terminal deletion mutant of Orf6 was generated, and the protein was purified to explore the function of the C terminus in ssDNA binding. We showed that full-length ORF6 binds cooperatively to M13 ssDNA, disrupting its secondary structure and extending it to a length equivalent to that of duplex M13 DNA. The width of the ORF6-ssDNA filament is 9 nm, and a 7.3-nm repeat can be distinguished along the filament axis. Fluorescence polarization analysis revealed that the wild-type and C-terminal mutant ORF6 proteins bind equally well to short ssDNA substrates, with dissociation constant (

K
d

) values of 2.2 × 10
−7
M and 1.5 × 10
−7
M, respectively. These values were confirmed by electrophoretic mobility shift assay (EMSA) analysis, which also suggested that binding by the full-length protein may involve both monomers and small multimers. While no significant difference in affinities of binding between full-length ORF6 and the C-terminal deletion mutant were observed with the short DNAs, binding of the C-terminal mutant protein to M13 ssDNA showed a clear lack of cooperativity as seen by electron microscopy (EM). Incubation of a duplex DNA containing a long single-stranded tail with double-helical ORF6 protein filaments revealed that the ssDNA segment can be enveloped within the protein filament without disrupting the filament structure.

IMPORTANCE
This work describes the biochemical characterization of the single-stranded DNA binding protein of KSHV, ORF6, central to viral DNA replication in infected cells. A C-terminal deletion mutant protein was generated to aid in understanding the role of the C terminus in DNA binding. Here we analyze the binding of the wild-type and mutant proteins to short oligomeric and longer genomic ssDNA substrates. Although it is capable of interacting with the short substrates, the inability of mutant ORF6 to form oligomers in solution hindered it from fully covering the long genomic substrates. We previously showed that ORF6 forms long filaments in solution, and we showed here that these can absorb ssDNA without disruption of the filament structure. This work will provide an important basis for future studies by us and/or others.
Prolapsed giant sigmoid lipoma: a rare cause of adult ischaemic intussusception
Authors: Elliott Mark , Martin Jennifer , Mullan Fred 
Published: May 2014

Intussusception is a rare cause of obstruction in adults and has a variable, non-specific presentation. Adult intussusception is usually associated with an underlying organic pathology, such as a benign or malignant tumour which acts as the lead point. Prolapse of the lead-point mass through the anal canal is an extremely rare presentation with very few reported cases in the literature. We describe a case of a 67-year-old man who presented with rectal prolapse of a large soft tissue mass. CT of the abdomen and barium enema revealed partial intussusception of an upper sigmoid lipomatous polyp. Examination under anaesthesia was performed and the prolapse reduced. A laparoscopic sigmoid colectomy was planned. The patient subsequently re-presented clinically unwell with a recurrent necrotic prolapsing mass. Laparotomy and sigmoid colectomy was performed and the patient recovered fully. The resected mass was a 7×4.5×4.0 cm necrotic sigmoid lipoma.
STRATEGIC ENVIRONMENTAL ASSESSMENT IN THE MEXICAN ELECTRICITY SECTOR
Authors: MONTAÑEZ-CARTAXO LUIS E. 
Published: May 2014

In Mexico, the Federal Commission of Electricity (CFE) is the public entity that is responsible for the annual preparation of the national programme of the electricity system development with a 15 year horizon (POISE in Spanish). Besides this national planning process, there are regional plans as well as others regarding the development of hydroelectric and geothermoelectric projects; these plans are essential inputs to prepare the POISE. Another key decision window is the site selection of the projects listed in the Program. For a few years the Environmental Protection Division of CFE has been promoting the incorporation of SEA into the decision-making processes of the company. Two regional SEAs have been made so far. This paper presents the actions carried out to incorporate SEA into CFE since 2002, as well as the methodologies followed in each of the two cases, and primarily the lessons learned from these experiences.
Piedra Pajarilla: a candidacy as a global heritage stone resource for Martinamor granite
Authors: Pereira Dolores , Gimeno Ana , Del Barrio Santiago 
Published: May 2014

Abstract
Piedra Pajarilla is the local name under which the Martinamor granite was known when it was quarried during the 19th century. It is a leucogranite of Hercynian age, and here we present its formal nomination as a ‘Global Heritage Stone Resource’. Piedra Pajarilla fits the proposed designation because it has been used for centuries in the construction of major historical and famous buildings in Salamanca, leading the city to being included in the UNESCO World Heritage list in 1988. Piedra Pajarilla is no longer quarried, and this nomination will help to maintain the historical quarry for the restoration of the monuments if blocks need to be replaced.