bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Local Features from Two Spanish Hospitals Reveals Common and Specific Traits at Multiple Levels of the Molecular Epidemiology of Metallo-β-Lactamase-Producing Pseudomonas spp
Authors: Viedma Esther , Estepa Vanesa , Juan Carlos , Castillo-Vera Jane , Rojo-Bezares Beatriz , Seral Cristina , Castillo Francisco Javier , Sáenz Yolanda , Torres Carmen , Chaves Fernando , Oliver Antonio
Published: February 2014

Twenty-seven well-characterized metallo-β-lactamase (MBL)-producing
Pseudomonas
strains from two distantly located hospitals were analyzed. The results revealed specific features defining the multilevel epidemiology of strains from each hospital in terms of species, clonality, predominance of high-risk clones, composition/diversity of integrons, and linkages of Tn
402
-related structures. Therefore, despite the global trends driving the epidemiology of MBL-producing
Pseudomonas
spp., the presence of local features has to be considered in order to understand this threat and implement proper control strategies.
Novel Regimens Identified in Mice for Treatment of Latent Tuberculosis Infection in Contacts of Patients with Multidrug-Resistant Tuberculosis
Authors: Lanoix Jean-Philippe , Betoudji Fabrice , Nuermberger Eric
Published: February 2014

Preventing the development of tuberculosis (TB) in contacts of patients with multidrug-resistant TB (MDR-TB) by the treatment of latent TB infection (LTBI) is highly desirable. However, few safe, well tolerated, and effective drugs are available to treat MDR-LTBI and the published guidance is limited. Fortunately, six new chemical entities from four classes developed to treat TB have entered clinical trials in the past decade. We tested three of these drugs alone and in combination in an experimental paucibacillary LTBI chemotherapy model using BALB/c and C3HeB/FeJ mice immunized with a recombinant strain of
Mycobacterium bovis
bacillus Calmette-Guérin (rBCG30) and then challenged with a low-dose aerosol of
M. tuberculosis
H37Rv. The regimens tested contained bedaquiline (TMC), PA-824 (Pa), sutezolid (PNU), and/or one of two fluoroquinolones. Control mice received rifampin (RIF) or isoniazid (INH). In BALB/c mice, TMC-containing regimens and the Pa-PNU combination were the most active test regimens and were at least as effective as RIF. Pa, PNU, and levofloxacin had activity comparable to that of INH. Virtually identical results were observed in C3HeB/FeJ mice. This study confirms the potent activity of TMC observed previously in BALB/c mice and highlights Pa alone or in combination with either PNU or a fluoroquinolone as a regimen worthy of evaluation in future clinical trials of MDR-LTBI. Given their closer pathological representation of human TB lesions, C3HeB/FeJ mice may become a preferred model for the experimental chemotherapy of LTBI. Future studies should evaluate additional clinically relevant LTBI regimens in this strain including relapse as an endpoint.
Variation in Potency and Spectrum of Tigecycline Activity against Bacterial Strains from U.S. Medical Centers since Its Approval for Clinical Use (2006 to 2012)
Authors: Sader Helio S. , Farrell David J. , Flamm Robert K. , Jones Ronald N.
Published: February 2014

Tigecycline was initially approved by the U.S. Food and Drug Administration (FDA) in June 2005. We assessed the evolution of tigecycline
in vitro
activities since the initial approval of tigecycline for clinical use by analyzing the results of 7 years (2006 to 2012) of data from the SENTRY Antimicrobial Surveillance Program in the United States. We also analyzed trends over time for key resistance phenotypes. The analyses included 68,608 unique clinical isolates collected from 29 medical centers and tested for susceptibility using reference broth microdilution methods. Tigecycline was highly active against Gram-positive organisms, with MIC
50
and MIC
90
values of 0.12 and 0.25 μg/ml for
Staphylococcus aureus
(28,278 strains; >99.9% susceptible), 0.06 to 0.12 and 0.12 to 0.25 μg/ml for enterococci (99.3 to 99.6% susceptible), and ≤0.03 and ≤0.03 to 0.06 μg/ml for streptococci (99.9 to 100.0% susceptible), respectively. When tested against 20,457
Enterobacteriaceae
strains, tigecycline MIC
50
and MIC
90
values were 0.25 and 1 μg/ml, respectively (98.3% susceptible using U.S. FDA breakpoints). No trend toward increasing tigecycline resistance (nonsusceptibility) was observed for any species or group during the study period. The prevalence of multidrug-resistant (MDR) and extensively drug-resistant (XDR)
Enterobacteriaceae
increased from 4.4 and 0.5%, in 2006 to 8.5 and 1.5% in 2012, respectively. During the same period, the prevalence of
Escherichia coli
and
Klebsiella
spp. with an extended-spectrum β-lactamase (ESBL) phenotype increased from 5.8 and 9.1% to 11.1 and 20.4%, respectively, whereas rates of meropenem-nonsusceptible
Klebsiella pneumoniae
escalated from 2.2% in 2006 to 10.8% in 2012. The results of this investigation show that tigecycline generally retained potent activities against clinically important organisms isolated in U.S. institutions, including MDR organism subsets of Gram-positive and Gram-negative pathogens.
Molecular Survey of the Dissemination of Two
bla
KPC
-Harboring IncFIA Plasmids in New Jersey and New York Hospitals
Authors: Chen Liang , Chavda Kalyan D. , Melano Roberto G. , Hong Tao , Rojtman Albert D. , Jacobs Michael R. , Bonomo Robert A. , Kreiswirth Barry N.
Published: February 2014

Klebsiella pneumoniae
carbapenemase (KPC)-producing
K. pneumoniae
strains have spread worldwide and become a major threat in health care facilities. Transmission of
bla
KPC
, the plasmid-borne KPC gene, can be mediated by clonal spread and horizontal transfer. Here, we report the complete nucleotide sequences of two novel
bla
KPC-3
-harboring IncFIA plasmids, pBK30661 and pBK30683. pBK30661 is 74 kb in length, with a mosaic plasmid structure; it exhibits homologies to several other plasmids but lacks the plasmid transfer operon (
tra
) and the origin of transfer (
oriT
) that are required for plasmid transfer. pBK30683 is a conjugative plasmid with a cointegrated plasmid structure, comprising a 72-kb element that highly resembles pBK30661 (>99.9% nucleotide identities) and an extra 68-kb element that harbors
tra
and
oriT
. A PCR scheme was designed to detect the distribution of
bla
KPC
-harboring IncFIA (pBK30661-like and pBK30683-like) plasmids in a collection of clinical
Enterobacteriaceae
isolates from 10 hospitals in New Jersey and New York. KPC-harboring IncFIA plasmids were found in 20% of 491
K. pneumoniae
isolates, and all carried
bla
KPC-3
. pBK30661-like plasmids were identified mainly in the epidemic sequence type 258 (ST258)
K. pneumoniae
clone, while pBK30683-like plasmids were widely distributed in ST258 and other
K. pneumoniae
sequence types and among non-
K. pneumoniae Enterobacteriaceae
species. This suggests that both clonal spread and horizontal plasmid transfer contributed to the dissemination of
bla
KPC
-harboring IncFIA plasmids in our area. Further studies are needed to understand the distribution of this plasmid group in other health care regions and to decipher the origins of pBK30661-like and pBK30683-like plasmids.
Matrix Metalloproteinase Inhibition Lowers Mortality and Brain Injury in Experimental Pneumococcal Meningitis
Authors: Liechti Fabian D. , Grandgirard Denis , Leppert David , Leib Stephen L.
Published: February 2014

Pneumococcal meningitis (PM) results in high mortality rates and long-lasting neurological deficits. Hippocampal apoptosis and cortical necrosis are histopathological correlates of neurofunctional sequelae in rodent models and are frequently observed in autopsy studies of patients who die of PM. In experimental PM, inhibition of matrix metalloproteinases (MMPs) and/or tumor necrosis factor (TNF)-converting enzyme (TACE) has been shown to reduce brain injury and the associated impairment of neurocognitive function. However, none of the compounds evaluated in these studies entered clinical development. Here, we evaluated two second-generation MMP and TACE inhibitors with higher selectivity and improved oral availability. Ro 32-3555 (Trocade, cipemastat) preferentially inhibits collagenases (MMP-1, -8, and -13) and gelatinase B (MMP-9), while Ro 32-7315 is an efficient inhibitor of TACE. PM was induced in infant rats by the intracisternal injection of live
Streptococcus pneumoniae
. Ro 32-3555 and Ro 32-7315 were injected intraperitoneally, starting at 3 h postinfection. Antibiotic (ceftriaxone) therapy was initiated at 18 h postinfection, and clinical parameters (weight, clinical score, mortality rate) were recorded. Myeloperoxidase activities, concentrations of cytokines and chemokines, concentrations of MMP-2 and MMP-9, and collagen concentrations were measured in the cerebrospinal fluid. Animals were sacrificed at 42 h postinfection, and their brains were assessed by histomorphometry for hippocampal apoptosis and cortical necrosis. Both compounds, while exhibiting disparate MMP and TACE inhibitory profiles, decreased hippocampal apoptosis and cortical injury. Ro 32-3555 reduced mortality rates and cerebrospinal fluid TNF, interleukin-1β (IL-1β) and collagen levels, while Ro 32-7315 reduced weight loss and cerebrospinal fluid TNF and IL-6 levels.
Protein Kinase C Mediates Enterohemorrhagic Escherichia coli O157:H7-Induced Attaching and Effacing Lesions
Authors: Shen-Tu Grace , Kim Hyunhee , Liu Mingyao , Johnson-Henry Kathene C. , Sherman Philip M.
Published: February 2014

Enterohemorrhagic
Escherichia coli
serotype O157:H7 causes outbreaks of diarrhea, hemorrhagic colitis, and the hemolytic-uremic syndrome.
E. coli
O157:H7 intimately attaches to epithelial cells, effaces microvilli, and recruits F-actin into pedestals to form attaching and effacing lesions. Lipid rafts serve as signal transduction platforms that mediate microbe-host interactions. The aims of this study were to determine if protein kinase C (PKC) is recruited to lipid rafts in response to
E. coli
O157:H7 infection and what role it plays in attaching and effacing lesion formation. HEp-2 and intestine 407 tissue culture epithelial cells were challenged with
E. coli
O157:H7, and cell protein extracts were then separated by buoyant density ultracentrifugation to isolate lipid rafts. Immunoblotting for PKC was performed, and localization in lipid rafts was confirmed with an anti-caveolin-1 antibody. Isoform-specific PKC small interfering RNA (siRNA) was used to determine the role of PKC in
E. coli
O157:H7-induced attaching and effacing lesions. In contrast to uninfected cells, PKC was recruited to lipid rafts in response to
E. coli
O157:H7. Metabolically active bacteria and cells with intact lipid rafts were necessary for the recruitment of PKC. PKC recruitment was independent of the intimin gene, type III secretion system, and the production of Shiga toxins. Inhibition studies, using myristoylated PKCζ pseudosubstrate, revealed that atypical PKC isoforms were activated in response to the pathogen. Pretreating cells with isoform-specific PKC siRNA showed that PKCζ plays a role in
E. coli
O157:H7-induced attaching and effacing lesions. We concluded that lipid rafts mediate atypical PKC signal transduction responses to
E. coli
O157:H7. These findings contribute further to the understanding of the complex array of microbe-eukaryotic cell interactions that occur in response to infection.
Role of Pht Proteins in Attachment of Streptococcus pneumoniae to Respiratory Epithelial Cells
Authors: Kallio Anna , Sepponen Kirsi , Hermand Philippe , Denoël Philippe , Godfroid Fabrice , Melin Merit
Published: February 2014

Pneumococcal adherence to mucosal surfaces is a critical step in nasopharyngeal colonization, but so far few pneumococcal adhesins involved in the interaction with host cells have been identified. PhtA, PhtB, PhtD, and PhtE are conserved pneumococcal surface proteins that have proven promising as vaccine candidates. One suggested virulence function of Pht proteins is to mediate adherence at the respiratory mucosa. In this study, we assessed the role of Pht proteins in pneumococcal binding to respiratory epithelial cells. Pneumococci were incubated with human nasopharyngeal epithelial cells (Detroit-562) and lung epithelial cells (A549 and NCI-H292), and the proportion of bound bacteria was measured by plating viable counts. Strains R36A (unencapsulated), D39 (serotype 2), 43 (serotype 3), 4-CDC (serotype 4), and 2737 (serotype 19F) with one or more of the four homologous Pht proteins deleted were compared with their wild-type counterparts. Also, the effect of anti-PhtD antibodies on the adherence of strain 2737 to the respiratory epithelial cells was studied. Our results suggest that Pht proteins play a role in pneumococcal adhesion to the respiratory epithelium. We also found that antibody to PhtD is able to inhibit bacterial attachment to the cells, suggesting that antibodies against PhtD present at mucosal surfaces might protect from pneumococcal attachment and subsequent colonization. However, the relative significance of Pht proteins to the ability of pneumococci to bind
in vitro
to epithelial cells depends on the genetic background and the capsular serotype of the strain.
Suppression of Antimicrobial Peptide Expression by Ureaplasma Species
Authors: Xiao Li , Crabb Donna M. , Dai Yuling , Chen Yuying , Waites Ken B. , Atkinson T. Prescott
Published: February 2014

Ureaplasma
species commonly colonize the adult urogenital tract and are implicated in invasive diseases of adults and neonates. Factors that permit the organisms to cause chronic colonization or infection are poorly understood. We sought to investigate whether host innate immune responses, specifically, antimicrobial peptides (AMPs), are involved in determining the outcome of
Ureaplasma
infections. THP-1 cells, a human monocytoid tumor line, were cocultured with
Ureaplasma parvum
and
U. urealyticum
. Gene expression levels of a variety of host defense genes were quantified by real-time PCR.
In vitro
antimicrobial activities of synthetic AMPs against
Ureaplasma
spp. were determined using a flow cytometry-based assay. Chromosomal histone modifications in host defense gene promoters were tested by chromatin immunoprecipitation (ChIP). DNA methylation status in the AMP promoter regions was also investigated. After stimulation with
U. parvum
and
U. urealyticum
, the expression of cell defense genes, including the AMP genes (
DEFB1
,
DEFA5
,
DEFA6
, and
CAMP
), was significantly downregulated compared to that of
TNFA
and
IL-8
, which were upregulated.
In vitro
flow cytometry-based antimicrobial assay revealed that synthetic peptides LL-37, hBD-3, and hBD-1 had activity against
Ureaplasma
spp. Downregulation of the AMP genes was associated with chromatin modification alterations, including the significantly decreased histone H3K9 acetylation with
U. parvum
infection. No DNA methylation status changes were detected upon
Ureaplasma
infection. In conclusion, AMPs have
in vitro
activity against
Ureaplasma
spp., and suppression of AMP expression might be important for the organisms to avoid this aspect of the host innate immune response and to establish chronic infection and colonization.
Enhanced Interaction of Vibrio cholerae Virulence Regulators TcpP and ToxR under Oxygen-Limiting Conditions
Authors: Fan Fenxia , Liu Zhi , Jabeen Nusrat , Birdwell L. Dillon , Zhu Jun , Kan Biao
Published: February 2014

Vibrio cholerae
is the causative agent of the diarrheal disease cholera. The ability of
V. cholerae
to colonize and cause disease requires the intricately regulated expression of a number of virulence factors during infection. One of the signals sensed by
V. cholerae
is the presence of oxygen-limiting conditions in the gut. It has been shown that the virulence activator AphB plays a key role in sensing low oxygen concentrations and inducing the transcription of another key virulence activator, TcpP. In this study, we used a bacterial two-hybrid system to further examine the effect of oxygen on different virulence regulators. We found that anoxic conditions enhanced the interaction between TcpP and ToxR, identified as the first positive regulator of
V. cholerae
virulence genes. We further demonstrated that the TcpP-ToxR interaction was dependent on the primary periplasmic protein disulfide formation enzyme DsbA and cysteine residues in the periplasmic domains of both ToxR and TcpP. Furthermore, we showed that in
V. cholerae
, an interaction between TcpP and ToxR is important for virulence gene induction. Under anaerobic growth conditions, we detected ToxR-TcpP heterodimers, which were abolished in the presence of the reducing agent dithiothreitol. Our results suggest that
V. cholerae
may sense intestinal anoxic signals by multiple components to activate virulence.
Mucosal Immunization with Recombinant Fusion Protein DnaJ-ΔA146Ply Enhances Cross-Protective Immunity against Streptococcus pneumoniae Infection in Mice via Interleukin 17A
Authors: Liu Yusi , Wang Hong , Zhang Shuai , Zeng Lingbin , Xu Xiuyu , Wu Kaifeng , Wang Wei , Yin Nanlin , Song Zhixin , Zhang Xuemei , Yin Yibing
Published: February 2014

Pneumolysin (Ply) and its variants are protective against pneumococcal infections in animal models, and as a Toll-like receptor 4 agonist, pneumolysin has been reported to be a mucosal adjuvant. DnaJ has been approved as a useful candidate vaccine protein; we therefore designed novel fusion proteins of DnaJ with a form of Ply that has a deletion of A146 (ΔA146Ply-DnaJ [the C terminus of ΔA146Ply connected with the N terminus of DnaJ] and DnaJ-ΔA146Ply [the C terminus of DnaJ connected with the N terminus of ΔA146Ply]) to test whether they are protective against focal and lethal pneumococcal infections and their potential protective mechanisms. The purified proteins were used to intranasally immunize the animals without additional adjuvant. Immunization with DnaJ-ΔA146Ply or DnaJ plus ΔA146Ply (Ply with a single deletion of A146) could significantly reduce
S. pneumoniae
colonization in the nasopharynx and lung relative with DnaJ alone. Additionally, we observed the best protection for DnaJ-ΔA146Ply-immunized mice after challenge with lethal doses of
S. pneumoniae
strains, which was comparable to that achieved by PPV23. Mice immunized with DnaJ-ΔA146Ply produced significantly higher levels of anti-DnaJ IgG in serum and secretory IgA (sIgA) in saliva than those immunized with DnaJ alone. The production of IL-17A was also striking in DnaJ-ΔA146Ply-immunized mice. IL-17A knockout (KO) mice did not benefit from DnaJ-ΔA146Ply immunization in colonization experiments, and sIgA production was impaired in IL-17A KO mice. Collectively, our results indicate a mucosal adjuvant potential for ΔA146Ply and that, without additional adjuvant, DnaJ-ΔA146Ply fusion protein exhibits extensive immune stimulation and is effective against pneumococcal challenges, properties which are partially attributed to the IL-17A-mediated immune responses.
The δ Subunit of RNA Polymerase Guides Promoter Selectivity and Virulence in Staphylococcus aureus
Authors: Weiss Andy , Ibarra J. Antonio , Paoletti Jessica , Carroll Ronan K. , Shaw Lindsey N.
Published: February 2014

In Gram-positive bacteria, and particularly the
Firmicutes
, the DNA-dependent RNA polymerase (RNAP) complex contains an additional subunit, termed the δ factor, or RpoE. This enigmatic protein has been studied for more than 30 years for various organisms, but its function is still not well understood. In this study, we investigated its role in the major human pathogen
Staphylococcus aureus
. We showed conservation of important structural regions of RpoE in
S. aureus
and other species and demonstrated binding to core RNAP that is mediated by the β and/or β′ subunits. To identify the impact of the δ subunit on transcription, we performed transcriptome sequencing (RNA-seq) analysis and observed 191 differentially expressed genes in the
rpoE
mutant. Ontological analysis revealed, quite strikingly, that many of the downregulated genes were known virulence factors, while several mobile genetic elements (SaPI5 and prophage ϕSA3usa) were strongly upregulated. Phenotypically, the
rpoE
mutant had decreased accumulation and/or activity of a number of key virulence factors, including alpha toxin, secreted proteases, and Panton-Valentine leukocidin (PVL). We further observed significantly decreased survival of the mutant in whole human blood, increased phagocytosis by human leukocytes, and impaired virulence in a murine model of infection. Collectively, our results demonstrate that the δ subunit of RNAP is a critical component of the
S. aureus
transcription machinery and plays an important role during infection.
A Broadly Implementable Research Course in Phage Discovery and Genomics for First-Year Undergraduate Students
Authors: Jordan Tuajuanda C. , Burnett Sandra H. , Carson Susan , Caruso Steven M. , Clase Kari , DeJong Randall J. , Dennehy John J. , Denver Dee R. , Dunbar David , Elgin Sarah C. R. , Findley Ann M. , Gissendanner Chris R. , Golebiewska Urszula P. , Guild Nancy , Hartzog Grant A. , Grillo Wendy H. , Hollowell Gail P. , Hughes Lee E. , Johnson Allison , King Rodney A. , Lewis Lynn O. , Li Wei , Rosenzweig Frank , Rubin Michael R. , Saha Margaret S. , Sandoz James , Shaffer Christopher D. , Taylor Barbara , Temple Louise , Vazquez Edwin , Ware Vassie C. , Barker Lucia P. , Bradley Kevin W. , Jacobs-Sera Deborah , Pope Welkin H. , Russell Daniel A. , Cresawn Steven G. , Lopatto David , Bailey Cheryl P. , Hatfull Graham F.
Published: February 2014

Engaging large numbers of undergraduates in authentic scientific discovery is desirable but difficult to achieve. We have developed a general model in which faculty and teaching assistants from diverse academic institutions are trained to teach a research course for first-year undergraduate students focused on bacteriophage discovery and genomics. The course is situated within a broader scientific context aimed at understanding viral diversity, such that faculty and students are collaborators with established researchers in the field. The Howard Hughes Medical Institute (HHMI) Science Education Alliance Phage Hunters Advancing Genomics and Evolutionary Science (SEA-PHAGES) course has been widely implemented and has been taken by over 4,800 students at 73 institutions. We show here that this alliance-sourced model not only substantially advances the field of phage genomics but also stimulates students’ interest in science, positively influences academic achievement, and enhances persistence in science, technology, engineering, and mathematics (STEM) disciplines. Broad application of this model by integrating other research areas with large numbers of early-career undergraduate students has the potential to be transformative in science education and research training.

IMPORTANCE
Engagement of undergraduate students in scientific research at early stages in their careers presents an opportunity to excite students about science, technology, engineering, and mathematics (STEM) disciplines and promote continued interests in these areas. Many excellent course-based undergraduate research experiences have been developed, but scaling these to a broader impact with larger numbers of students is challenging. The Howard Hughes Medical Institute (HHMI) Science Education Alliance Phage Hunting Advancing Genomics and Evolutionary Science (SEA-PHAGES) program takes advantage of the huge size and diversity of the bacteriophage population to engage students in discovery of new viruses, genome annotation, and comparative genomics, with strong impacts on bacteriophage research, increased persistence in STEM fields, and student self-identification with learning gains, motivation, attitude, and career aspirations.
Osteochondroma of condyle: case discussion and review of treatment modalities
Authors: Arora Piyush , Deora Shakti Singh , Kiran Shital , Bargale Seema Dinesh
Published: February 2014

Temporomandibular joint (TMJ) forms a synovial articulation between the condyle and the cranium. It is a complex joint and shows hinge and gliding movements. Unlike other articulating heads, condyle grows with intramembranous ossification. TMJ is subjected to excessive loads throughout life as it supports essential functions such as mastication, deglutition, speech and respiration. Traumatic, neoplastic or non-neoplastic pathologies sometimes necessitate joint replacement therapy. Osteochondroma is one such benign tumour originating from condyle which requires surgical replacement of condyle with prosthesis. Various replacement methods have been designed in the past. Alloplastic grafts have been successfully used in joint replacement surgeries like hip joint, knee joint, etc. This case discussion supports the use of titanium-made condylar prosthesis for long-term functional stability of TMJ.
Unidentified intralesional and intracellular coccoid microorganism discovered in the young man with a diffuse erosive gastroduodenitis and multiple superficial ulcerations
Authors: Okada Takayuki , Adkins Graham
Published: February 2014

AHelicobacterpylori-negative young Japanese man with dyspeptic symptoms suffered from a diffuse erosive gastroduodenitis and multiple superficial ulcerations. Histology and electron microscopic examinations on the biopsy specimens revealed the presence of multiple unidentified intralesional and intracellular coccoid microorganisms in the pathological gastroduodenal mucosa. Microaerophilic and anaerobic Gram-negative coccoid and filamentobacillary bacteria were cultured from the gastric aspirate. The triple therapy containing tetracycline for 14 days followed by 4 months treatment with omeprazole resulted in the resolution of the gastroduodenal pathology. The question, therefore, was raised regarding a possible role for the cultured coccoid bacteria in the pathogenesis. 16S rRNA gene sequence analysis of the isolated Gram-negative coccoid bacteria revealed a close relationship withHaemophilus haemolyticus. The unidentified coccoid microorganisms and cultured X and V factors independent coccoid bacteria, however, shared similar phenotypic, microbiological and pathological characteristics to the novel Gram-negativeStreptococcaceae:Okadaella gastrococcus.
Climate change effects on human health: projections of temperature-related mortality for the UK during the 2020s, 2050s and 2080s
Authors: Hajat Shakoor , Vardoulakis Sotiris , Heaviside Clare , Eggen Bernd
Published: February 2014

Background

The most direct way in which climate change is expected to affect public health relates to changes in mortality rates associated with exposure to ambient temperature. Many countries worldwide experience annual heat-related and cold-related deaths associated with current weather patterns. Future changes in climate may alter such risks. Estimates of the likely future health impacts of such changes are needed to inform public health policy on climate change in the UK and elsewhere.

Methods

Time-series regression analysis was used to characterise current temperature-mortality relationships by region and age group. These were then applied to the local climate and population projections to estimate temperature-related deaths for the UK by the 2020s, 2050s and 2080s. Greater variability in future temperatures as well as changes in mean levels was modelled.

Results

A significantly raised risk of heat-related and cold-related mortality was observed in all regions. The elderly were most at risk. In the absence of any adaptation of the population, heat-related deaths would be expected to rise by around 257% by the 2050s from a current annual baseline of around 2000 deaths, and cold-related mortality would decline by 2% from a baseline of around 41 000 deaths. The cold burden remained higher than the heat burden in all periods. The increased number of future temperature-related deaths was partly driven by projected population growth and ageing.

Conclusions

Health protection from hot weather will become increasingly necessary, and measures to reduce cold impacts will also remain important in the UK. The demographic changes expected this century mean that the health protection of the elderly will be vital.
Impact of chronic obstructive pulmonary disease on morbidity and mortality after myocardial infarction
Authors: Andell Pontus , Koul Sasha , Martinsson Andreas , Sundström Johan , Jernberg Tomas , Smith J Gustav , James Stefan , Lindahl Bertil , Erlinge David
Published: February 2014

Aim

To gain a better understanding of the impact of chronic obstructive pulmonary disease (COPD) on long-term mortality in patients with myocardial infarction (MI) and identify areas where the clinical care for these patients may be improved.

Methods

Patients hospitalised for MI between 2005 and 2010 were identified from the nationwide Swedish SWEDEHEART registry. Patients with MI and a prior COPD hospital discharge diagnosis were compared to patients with MI without a prior COPD hospital discharge diagnosis for the primary endpoint of all-cause mortality at 1 year after MI. Secondary endpoints included rates of reinfarction, new-onset stroke, new-onset bleeding and new-onset heart failure at 1 year.

Results

A total of 81 191 MI patients were included, of which 4867 (6%) had a COPD hospital discharge diagnosis at baseline. Patients with COPD showed a significantly higher unadjusted 1-year mortality (24.6 vs 13.8%) as well as a higher rate of reinfarction, new-onset bleeding and new-onset heart failure post-MI. After adjustment for potential confounders, including comorbidities and treatment, the patients with COPD still showed a significantly higher 1-year mortality (HR 1.14, 95% CI 1.07 to 1.21) as well as a higher rate of new-onset heart failure (HR 1.35, 95% CI 1.24 to 1.47), whereas no significant association between COPD and myocardial reinfarction or new-onset bleeding remained.

Conclusions

In this nationwide contemporary study, patients with COPD frequently had an atypical presentation, less often underwent revascularisation and less often received guideline-recommended secondary preventive medications of established benefit. Prior COPD was associated with a higher 1-year mortality and a higher risk of subsequent new-onset heart failure after MI. The association seems to be mainly explained by differences in background characteristics, comorbidities and treatment, although a minor part might be explained by COPD in itself. Improved in-hospital MI treatment and post-MI secondary prevention according to the guidelines may lower the mortality in this high-risk population.
Analytical solution for determining the required strength of a side-exposed mine backfill containing a plug
Authors: Li Li
Published: February 2014

Backfilling is well known in the mining industry. A basic issue associated with mine backfill design is the determination of the strength of the backfill required to maintain the stability of the backfill body upon removal of a side wall when an adjacent secondary stope is excavated. This task is usually accomplished using a solution proposed by Mitchell et al. in the early 1980s. Recently, this solution has been reviewed and a modified solution has been proposed. These existing solutions, however, were developed for a uniform backfill. In practice, mine stopes are usually divided into primary and secondary stopes. Primary stopes are often backfilled in two stages: a plug pour and a final pour. In many cases, the cement content of the plug pour is higher than that of the final pour. The positive effect of the stronger plug is neglected in both the original and the modified Mitchell et al. solutions. Here, a new analytical solution is developed for estimating the required strength of a laterally exposed backfill by taking the plug into account. The proposed solution reduces to the modified Mitchell et al. solution if the plug pour and final pour have the same cement content. If the plug pour has a cement content higher than that of the final pour, the required backfill strength calculated with the proposed solution is lower than the values estimated with the modified Mitchell et al. solution; the same conclusion can be drawn to the comparison between the proposed solution and the original Mitchell et al. solution when the bond cohesion along the side walls is close to the cohesion of the backfill. Furthermore, the proposed solution indicates that an optimal cohesion ratio between the plug and final pours exists: there is no benefit in using excessively high cement content in the plug pour. It is noted that the proposed solution is valid only for high, narrow backfilled stopes, solutions for low and wide backfilled stopes are under development.
Estimation of rockburst wall-rock velocity invoked by slab flexure sources in deep tunnels
Authors: Qiu Shili , Feng Xiating , Zhang Chuanqing , Xiang Tianbing
Published: February 2014

For rock support in burst-prone ground, the wall-rock velocity adjacent to the surface of underground openings is a vital support design parameter, and depends on the seismic source mechanism inducing rockburst damage. In this study, to estimate the wall-rock velocity evoked only by rock slab buckling (an important rockburst source mechanism), a comprehensive velocity assessment method is proposed, using an excellent slab column buckling model with a small eccentricity, which relies on a novel compressive or tensile buckling failure criterion of rock slab. The true-triaxial loading–unloading tests and rockburst case analyses reveal that rock mass slabbing induced by high rock stress has major impacts on the evolution and formation of buckling rockburst in deep tunnels. Using a method based on the energy balance principle, the slabbing thickness of intact rock mass is also calculated by an analytical method, which indicates that the slabbing thickness parameter has a nonlinear relation to the following six parameters: uniaxial tensile strength (UTS), uniaxial compressive strength (UCS), normal stress (σn), length of joint (L), friction angle ([Formula: see text]), and joint roughness coefficient (JRC). These proposed models and methods have been quite successfully applied to rockburst and slabbing cases occurring in deep tunnels. These applications show that slab flexure is an important source mechanism invoking high wall-rock velocities and leading to severe rockburst damages in the area surrounding deep tunnels.
Density functional theory study of electric field effects on the isomerization of a photochromic molecular switch based on 1,2-dithienylethene
Authors: Zahedi Ehsan , Mozaffari Majid , Karimi Fereshteh-Sadat , Nouri Azita
Published: February 2014

Structural and electronic properties of 1,2-bis(5-methyl-[2,2′-bithiophen]-4-yl)cyclopent-1-ene in closed form and open form under various external electric field with strengths, 0, 10 × 10−4, 20 × 10−4, 30 × 10−4, 40 × 10−4, and 50 × 10−4a.u., were studied using the DFT-B3LYP/6-31G* method. As a positive index, structural parameters, length of the photoisomers, and the electronic spatial extents are almost stable at different external electric fields. The UV-Vis electronic spectrum based on time-dependent density functional theory indicated that the HOMO → LUMO transition in the closed form under different electric field strengths is strongly allowed, whereas is very weak in the open form. Electronic response parameters such as the HOMO−LUMO gap, electric dipole moment, and polarizability showed that electric conductivity of the closed form at different field strengths is greater than in the open form. Results of electronic density of states show that at high external electric field, the conductivity of the open form and closed form will be probably equal and switching behavior cannot be observed. Isomerization of the closed form to the open form at different external electric fields can be considered as exothermic and spontaneous.
A Note on Some Fuchsian Groups
Authors: Keskin Refik
Published: February 2014

In this paper, we introduce some Fuchsian groups and calculate their parabolic class numbers. In addition, we give two conjectures concerning with the parabolic class number.
Finite Groups Whose Cyclic Subnormal Subgroups Are Permutable
Authors: Robinson Derek J. S.
Published: February 2014

Finite groups in which each cyclic subnormal subgroup is Sylow-permutable, permutable or normal are investigated. Characterizations are found in both the soluble and insoluble cases.
n-Isoclinism Classes and n-Nilpotency Degree of Finite Groups
Authors: Moghaddam Mohammad Reza R. , Salemkar Ali Reza , Chiti Kazem
Published: February 2014

Gallagher (1970) and Gustafson (1973) introduced the commutativity degree of a finite group. In this paper, we define the n-nilpotency degree of finite groups for n ≥ 1, and prove some results as Lescot (1995) does for a certain class of groups. In particular, it is shown that the n-isoclinism of finite groups preserves their n-nilpotency degrees. Finally, some sharper and more general upper bound than previously known is constructed for the commutativity degree of non-abelian finite groups.
On Duality Relative to Self-orthogonal Bimodules
Authors: Wu Jun , Tong Wenting
Published: February 2014

Let R be a left and right Noetherian ring and RωR a faithfully balanced self-orthogonal bimodule. We introduce the notions of special embeddings and modules of ω-D-class n, and then give some characterizations of them. As an application, we study the properties of RωR with finite injective dimension. Our results extend the main results in [4].
Another Existence and Uniqueness Proof for the Higman–Sims Simple Group
Authors: Michler Gerhard O. , Previtali Andrea
Published: February 2014

In this article, we give a short proof for the existence and uniqueness of the Higman–Sims sporadic simple group 𝖧𝖲 by means of the first author's algorithm [17] and uniqueness criterion [18], respectively. We realize 𝖧𝖲 as a subgroup of GL 22(11), and determine its automorphism group Aut (𝖧𝖲). We also give a presentation for Aut (𝖧𝖲) in terms of generators and relations. Furthermore, the character table of 𝖧𝖲 is determined and representatives of its conjugacy classes are given as short words in its generating matrices inside GL 22(11).
Minimal Flat Resolutions of Artinian Modules
Authors: Payrovi Sh.
Published: February 2014

The purpose of this paper is to establish connection between the minimal flat resolutions of Artinian modules and the concept of cosequences in commutative algebra. The main result of this paper leads to a characterization of local Cohen–Macaulay rings in terms of vanishing property of the dual Bass numbers of certain Artinian modules.
Radicals of Semilattice-graded Rings
Authors: Chen Yuqun , Shum K. P. , Hao Zhifeng
Published: February 2014

Let [Formula: see text] be a semilattice Ω-graded ring and P a radical. Conditions are found under which [Formula: see text] if and only if [Formula: see text] for all α, β ∈ Ω. Examples are given to show that some conditions cannot be removed.
A Remark on the Green Correspondence on G-Algebras
Authors: Harris Morton E.
Published: February 2014

In the context of G-algebras, we prove that Green correspondent points satisfy some important properties that are suggested by the classical finite group Green correspondence.
The Structure of G/ Φ (G) in Terms of σ (G)
Authors: Jamali Alireza , Mousavi Hamid
Published: February 2014

Let G be a finite group. We let [Formula: see text] and σ (G) denote the number of maximal subgroups of G and the least positive integer n such that G is written as the union of n proper subgroups, respectively. In this paper, we determine the structure of G/ Φ (G) when G is a finite soluble group with [Formula: see text].
Exactness of Complexes of Modules over Schur Superalgebras
Authors: Grishkov Alexandr N. , Marko František , Zubkov Alexandr N.
Published: February 2014

In this paper, we study tensor products of injective modules and exactness of certain naturally appearing complexes of projective and injective modules over Schur superalgebras over an algebraically closed field K of characteristic p > 2. In particular, for the complex [Formula: see text] of projective modules P(i) = Sξ 1i(m+1)r-i given by multiplication by ui = ξ 1i(m+1)r-i, 1i+1 (m+1)r-i-1, we determine all of the terms where it is exact.
The Lie Pseudoalgebra of an Anchored Module
Authors: Popescu Paul
Published: February 2014

The aim of this paper is to define and to construct some ∞-Lie functors from two categories of anchored modules which admit linear connections to the corresponding categories of Lie pseudoalgebras; the isomorphism class of the Lie pseudoalgebra does not depend on the linear connection or on the corresponding bracket. In the particular case of a module, the ∞-Lie algebra is isomorphic with the free Lie algebra of the module in Bourbaki's sense.
Factorisable Semigroups of Linear Transformations
Authors: Ittharat Jirasook , Sullivan R. P.
Published: February 2014

Let P(X) be the semigroup of all partial transformations of a set X. A subsemigroup S of P(X) is factorisable if S = GE = EH, where G, H are subgroups of S and E is the set of idempotents in S. In 2001, Jampachon, Saichalee and Sullivan proved a simple result that generalized most of the previous work on factorisable subsemigroups of P(X). They also determined when the semigroup T(V) of all linear transformations of a vector space V is factorisable. In this paper, we extend that work to partial linear transformations of V and consider the notion of locally factorisable for such semigroups.
A Topological Study of Some Groups Arising from Cellular Quotients
Authors: Cavicchioli Alberto , Spaggiari Fulvia , Wang Moon-Ok
Published: February 2014

Kim and Kostrikin constructed in [8, 9] a tessellation on the boundary of a polyhedral 3-cell consisting of 8n pentagons (n ≥ 1). The tessellation produces a family of closed connected orientable 3-manifolds (denoted by M1(n) in the quoted papers) with spines corresponding to certain presentations of their fundamental groups. We investigate the topological and algebraic properties of such groups together with their derived quotients and split extensions, and completely classify the considered manifolds.
Groups Satisfying the Minimal Condition on Subnormal Non-normal Subgroups
Authors: De Mari Fausto , de Giovanni Francesco
Published: February 2014

In this paper, the structure of (generalized) soluble groups for which the set of all subnormal non-normal subgroups satisfies the minimal condition is described, taking as a model the known theory of groups in which normality is a transitive relation.
Finite Groups with Poles
Authors: Deaconescu Marian , Walls Gary L.
Published: February 2014

This paper studies the finite groups G that have a pair (A,B) of non-trivial proper subgroups satisfying the condition that for every H ⩽ G either A ⩽ H or H ⩽ B.
Induction and Restriction of Lifts of π-Partial Characters
Authors: Lewis Mark L.
Published: February 2014

In this paper, we study lattices of subgroups that can be used to obtain lifts of π-partial characters. In particular, we find a condition on the lattices so that the associated lifts will be well-behaved regarding induction and restriction on normal subgroups. We show that the lattices obtained from all subnormal subgroups have this property, but the lattices obtained from all normal subgroups do not.
Extensions of Exchange QB-Rings
Authors: Chen Huanyin
Published: February 2014

Let I be an exchange QB-ideal of a unital ring R. It is shown that for any regular A∈ Mn(I), there exist U, V∈ Mn(R)q-1∩ (In+Mn(I)) such that UAV= diag (e1,…,en) for some idempotents e1,…,en ∈ I.
Weakly Polymatroidal Ideals
Authors: Kokubo Masako , Hibi Takayuki
Published: February 2014

The concept of the weakly polymatroidal ideal, which generalizes both the polymatroidal ideal and the prestable ideal, is introduced. A fundamental fact is that every weakly polymatroidal ideal has a linear resolution. One of the typical examples of weakly polymatroidal ideals arises from finite partially ordered sets. We associate each weakly polymatroidal ideal with a finite sequence, alled the polymatroidal sequence, which will be useful for the computation of graded Betti numbers of weakly polymatroidal ideals as well as for the construction of weakly polymatroidal ideals.
Continuity of the Inverse in Pseudocompact Paratopological Groups
Authors: Romaguera S. , Sanchis M.
Published: February 2014

By a celebrated theorem of Numakura, a Hausdorff compact topological semigroup with two-sided cancellation is a group which has inverse continuous, i.e., it is a topological group. We improve Numakura's Theorem in the realm of non-Hausdorff topological semigroups. This improvement together with some properties of pseudocompact nature in the field of bitopological spaces is used in order to prove that a T0 paratopological group (G,τ) is a (Hausdorff) pseudocompact topological group if and only if (G, τ ∨ τ-1) is pseudocompact or, equivalently, G is Gδ-dense in the Stone–Čech bicompactification [Formula: see text] of (G, τ, τ-1). We also present a version for paratopological groups of the renowned Comfort–Ross Theorem stating that a topological group is pseudocompact if and only if its Stone–Čech compactification is a topological group.
On Sequentially Co-Cohen–Macaulay Modules
Authors: Dung Nguyen Thi
Published: February 2014

In this paper, we define the notion of dimension filtration of an Artinian module and study a class of Artinian modules, called sequentially co-Cohen–Macaulay modules, which contains strictly all co-Cohen–Macaulay modules. Some characterizations of co-Cohen–Macaulayness in terms of the Matlis duality and of local homology are also given.
Non-commutative Poisson Algebra Structures on the Lie Algebra $so_n\widetilde{({\Bbb C}_Q)}$
Authors: Tong Jie , Jin Quanqin
Published: February 2014

Non-commutative Poisson algebras are the algebras having both an associative algebra structure and a Lie algebra structure together with the Leibniz law. In this paper, the non-commutative poisson algebra structures on [Formula: see text] are determined.
A Note on Periodic Rings
Authors: Dorbidi H. R.
Published: February 2014

Let S be a semigroup. The degree of S is the smallest natural number r such that for each x ∈ S, xn(x)+r = xn(x), where n(x) ∈ ℕ. If such a number r does not exist, we say that the degree of S is infinite. For a group G, this coincides with the exponent of G. We prove that for a periodic ring R, the degree of R equals exp (U(R)), where U(R) denotes the unit group of R. Then we determine all degrees for any rings.
Deformation Theory of Dialgebra Morphisms
Authors: Yau Donald
Published: February 2014

An algebraic deformation theory of dialgebra morphisms is obtained.
Recognizing Finite Groups Through Order and Degree Pattern
Authors: Moghaddamfar A. R. , Zokayi A. R.
Published: February 2014

The degree pattern of a finite group G is introduced in [10] and it is proved that the following simple groups are uniquely determined by their degree patterns and orders: all sporadic simple groups, alternating groups Ap (p ≥ 5 is a twin prime) and some simple groups of Lie type. In this paper, we continue this investigation. In particular, we show that the automorphism groups of sporadic simple groups (except Aut (J2) and Aut (McL)), all simple C22-groups, the alternating groups Ap, Ap+1, Ap+2 and the symmetric groups Sp, Sp+1, where p is a prime, are also uniquely determined by their degree patterns and orders.
Generalized Regular Sequence and Finiteness of Local Cohomology Modules
Authors: Mafi A. , Saremi H.
Published: February 2014

Let R be a commutative Noetherian local ring, 𝔞 an ideal of R, and M a finitely generated generalized f-module. Let t be a positive integer such that [Formula: see text] and t > dim M - dim M/𝔞M. In this paper, we prove that there exists an ideal 𝔟 ⊇ 𝔞 such that (1) dim M - dim M/𝔟M = t; and (2) the natural homomorphism [Formula: see text] is an isomorphism for all i > t and it is surjective for i = t. Also, we show that if [Formula: see text] is a finite set for all i < t, then there exists an ideal 𝔟 of R such that dim R/𝔟 ≤ 1 and [Formula: see text] for all i < t.