bluuebunny/crossref_metadata_2025_split huggingface dataset:
Targeted lamellar keratoplasty in the horse: A paradigm shift in equine corneal transplantation
Authors: BROOKS D. E. 
Published: March 2011

SummaryMany equine keratopathies primarily affect individual layers of the cornea. Targeted lamellar keratoplasty rather than full thickness penetrating keratoplasty (PK) seems most appropriate to the microsurgical management of many of these equine keratopathies. Despite the positive results with PK in the horse the author now suggests that this procedure should be rarely utilised in the treatment of equine keratitis. Selective lamellar surgical replacement of only the diseased corneal layers while retaining unaffected normal corneal layers represents a new paradigm shift in the field of corneal transplantation in the horse.
Generation and Screening of Pichia pastoris Strains with Enhanced Protein Production by Use of Microengraving
Authors: Panagiotou Vasiliki , Love Kerry Routenberg , Jiang Bo , Nett Juergen , Stadheim Terrance , Love J. Christopher 
Published: March 2011

ABSTRACTThe selection of highly productive cell lines remains a key step for manufacturing therapeutic proteins. Microengraving was used to screen chemically mutagenized populations ofPichia pastorisfor increased production of an Fc fragment. Clones retrieved following three rounds of mutagenesis yielded titers 2.65-fold greater than those of the parental strain.
Specific Electromagnetic Effects of Microwave Radiation on Escherichia coli
Authors: Shamis Yury , Taube Alex , Mitik-Dineva Natasa , Croft Rodney , Crawford Russell J. , Ivanova Elena P. 
Published: March 2011

ABSTRACT

The present study investigated the effects of microwave (MW) radiation applied under a sublethal temperature on
Escherichia coli
. The experiments were conducted at a frequency of 18 GHz and at a temperature below 40°C to avoid the thermal degradation of bacterial cells during exposure. The absorbed power was calculated to be 1,500 kW/m
3
, and the electric field was determined to be 300 V/m. Both values were theoretically confirmed using CST Microwave Studio 3D Electromagnetic Simulation Software. As a negative control,
E. coli
cells were also thermally heated to temperatures up to 40°C using Peltier plate heating. Scanning electron microscopy (SEM) analysis performed immediately after MW exposure revealed that the
E. coli
cells exhibited a cell morphology significantly different from that of the negative controls. This MW effect, however, appeared to be temporary, as following a further 10-min elapsed period, the cell morphology appeared to revert to a state that was identical to that of the untreated controls. Confocal laser scanning microscopy (CLSM) revealed that fluorescein isothiocyanate (FITC)-conjugated dextran (150 kDa) was taken up by the MW-treated cells, suggesting that pores had formed within the cell membrane. Cell viability experiments revealed that the MW treatment was not bactericidal, since 88% of the cells were recovered after radiation. It is proposed that one of the effects of exposing
E. coli
cells to MW radiation under sublethal temperature conditions is that the cell surface undergoes a modification that is electrokinetic in nature, resulting in a reversible MW-induced poration of the cell membrane.
Adherence and Cytokine Induction in Caco-2 Cells by Bacterial Populations from a Three-Stage Continuous-Culture Model of the Large Intestine
Authors: Bahrami Bahram , Child Matthew W. , Macfarlane Sandra , Macfarlane George T. 
Published: March 2011

ABSTRACTAdherence of bacteria to epithelial cells is an important step in colonization and immune modulation in the large bowel. The aims of this study were to use a three-stage continuous-culture system (CCS) to investigate how environmental factors affect bacterial attachment to Caco-2 cells and modulation of cytokine expression by gut microorganisms, including a probioticBifidobacterium longumstrain, DD2004. The CCS simulated environmental conditions in the proximal large intestine (vessel 1 [V1]) and distal colon (V2 and V3) at two different system retention times (R) within the range of normal colonic transits (20 and 60 h). The model was inoculated with human fecal material, and fluorescencein situhybridization (FISH) was used to characterize microbial populations and to assess bacterial attachment to Caco-2 cells. Real-time quantitative PCR (qPCR) was employed to measure cytokine gene expression following challenge with bacteria from different components of the CCS in the presence and absence ofB. longum. At anRof 60 h, bacterial adherence increased from V1 to V3, but this trend was reversed at anRof 20 h. Atopobia were the predominant adherent organisms detected at both system retention times in each culture vessel. Modulation of transforming growth factor β1 (TGF-β1), interleukin 6 (IL-6), and IL-18 gene expression by CCS bacteria was marked at anRof 60 h, while at anRof 20 h, IL-4, IL-10, TGF-β2, IL-1α, and tumor necrosis factor alpha (TNF-α) were significantly affected. The addition ofB. longumaffected cytokine expression significantly at both retention times. This study demonstrates that environmental determinants regulate the adherence properties of intestinal bacteria and their abilities to regulate cytokine synthesis.
Coupling of Dimethylsulfide Oxidation to Biomass Production by a Marine Flavobacterium
Authors: Green David H. , Shenoy Damodar M. , Hart Mark C. , Hatton Angela D. 
Published: March 2011

ABSTRACT

Dimethylsulfide (DMS) is an important climatically active gas. In the sea, DMS is produced primarily by microbial metabolism of the compatible solute dimethylsulfoniopropionate. Laboratory growth of
Bacteroidetes
with DMS resulted in its oxidation to dimethyl sulfoxide but only in the presence of glucose. We hypothesized that electrons liberated from sulfur oxidation were used to augment biomass production.
Fungal Gene Expression on Demand: an Inducible, Tunable, and Metabolism-Independent Expression System for Aspergillus niger
Authors: Meyer Vera , Wanka Franziska , van Gent Janneke , Arentshorst Mark , van den Hondel Cees A. M. J. J. , Ram Arthur F. J. 
Published: March 2011

ABSTRACT

Filamentous fungi are the cause of serious human and plant diseases but are also exploited in biotechnology as production platforms. Comparative genomics has documented their genetic diversity, and functional genomics and systems biology approaches are under way to understand the functions and interaction of fungal genes and proteins. In these approaches, gene functions are usually inferred from deletion or overexpression mutants. However, studies at these extreme points give only limited information. Moreover, many overexpression studies use metabolism-dependent promoters, often causing pleiotropic effects and thus limitations in their significance. We therefore established and systematically evaluated a tunable expression system for
Aspergillus niger
that is independent of carbon and nitrogen metabolism and silent under noninduced conditions. The system consists of two expression modules jointly targeted to a defined genomic locus. One module ensures constitutive expression of the tetracycline-dependent transactivator rtTA2
S
-M2, and one module harbors the rtTA2
S
-M2-dependent promoter that controls expression of the gene of interest (the Tet-on system). We show here that the system is tight, responds within minutes after inducer addition, and allows fine-tuning based on the inducer concentration or gene copy number up to expression levels higher than the expression levels of the
gpdA
promoter. We also validate the Tet-on system for the generation of conditional overexpression mutants and demonstrate its power when combined with a gene deletion approach. Finally, we show that the system is especially suitable when the functions of essential genes must be examined.
The Issue of Secretion in Heterologous Expression of Clostridium cellulolyticum Cellulase-Encoding Genes in Clostridium acetobutylicum ATCC 824
Authors: Mingardon Florence , Chanal Angélique , Tardif Chantal , Fierobe Henri-Pierre 
Published: March 2011

ABSTRACT

The genes encoding the cellulases Cel5A, Cel8C, Cel9E, Cel48F, Cel9G, and Cel9M from
Clostridium cellulolyticum
were cloned in the
C. acetobutylicum
expression vector pSOS952 under the control of a Gram-positive constitutive promoter. The DNA encoding the native leader peptide of the heterologous cellulases was maintained. The transformation of the solventogenic bacterium with the corresponding vectors generated clones in the cases of Cel5A, Cel8C, and Cel9M. Analyses of the recombinant strains indicated that the three cellulases are secreted in an active form to the medium. A large fraction of the secreted cellulases, however, lost the C-terminal dockerin module. In contrast, with the plasmids pSOS952-cel9E, pSOS952-cel48F, and pSOS952-cel9G no colonies were obtained, suggesting that the expression of these genes has an inhibitory effect on growth. The deletion of the DNA encoding the leader peptide of Cel48F in pSOS952-cel48F, however, generated strains of
C. acetobutylicum
in which mature Cel48F accumulates in the cytoplasm. Thus, the growth inhibition observed when the wild-type
cel48F
gene is expressed seems related to the secretion of the cellulase. The weakening of the promoter, the coexpression of miniscaffoldin-encoding genes, or the replacement of the native signal sequence of Cel48F by that of secreted heterologous or endogenous proteins failed to generate strains secreting Cel48F. Taken together, our data suggest that a specific chaperone(s) involved in the secretion of the key family 48 cellulase, and probably Cel9G and Cel9E, is missing or insufficiently synthesized in
C. acetobutylicum
.
Regulation of Type VI Secretion Gene Clusters by σ
54
and Cognate Enhancer Binding Proteins
Authors: Bernard Christophe S. , Brunet Yannick R. , Gavioli Marthe , Lloubès Roland , Cascales Eric 
Published: March 2011

ABSTRACT

Type VI secretion systems (T6SS) are bacteriophage-derived macromolecular machines responsible for the release of at least two proteins in the milieu, which are thought to form an extracellular appendage. Although several T6SS have been shown to be involved in the virulence of animal and plant pathogens, clusters encoding these machines are found in the genomes of most species of Gram-negative bacteria, including soil, marine, and environmental isolates. T6SS have been associated with several phenotypes, ranging from virulence to biofilm formation or stress sensing. Their various environmental niches and large diversity of functions are correlated with their broad variety of regulatory mechanisms. Using a bioinformatic approach, we identified several clusters, including those of
Vibrio cholerae
,
Aeromonas hydrophila
,
Pectobacterium atrosepticum
,
Pseudomonas aeruginosa
,
Pseudomonas syringae
pv. tomato, and a
Marinomonas
sp., which possess typical −24/−12 sequences, recognized by the alternate sigma factor sigma 54 (σ
54
or σ
N
). σ
54
, which directs the RNA polymerase to these promoters, requires the action of a bacterial enhancer binding protein (bEBP), which binds to
cis
-acting upstream activating sequences. Putative bEBPs are encoded within the T6SS gene clusters possessing σ
54
boxes. Using
in vitro
binding experiments and
in vivo
reporter fusion assays, we showed that the expression of these clusters is dependent on both σ
54
and bEBPs.
Complete Genome Sequence of the Proteolytic Clostridium botulinum Type A5 (B3′) Strain H04402 065
Authors: Carter Andrew T. , Pearson Bruce M. , Crossman Lisa C. , Drou Nizar , Heavens Darren , Baker David , Febrer Melanie , Caccamo Mario , Grant Kathie A. , Peck Michael W. 
Published: March 2011

ABSTRACT

H04402 065 is one of a very small group of strains of proteolytic
Clostridium botulinum
that form type A5 neurotoxin. Here, we report the complete 3.9-Mb genome sequence and annotation of strain H04402 065, which was isolated from a botulism patient in the United Kingdom in 2004.
Absence of PmrAB-Mediated Phosphoethanolamine Modifications of Citrobacter rodentium Lipopolysaccharide Affects Outer Membrane Integrity
Authors: Viau Charles , Le Sage Valerie , Ting Daniel K. , Gross Jeremy , Le Moual Hervé 
Published: March 2011

ABSTRACT

The PmrAB two-component system of enterobacteria regulates a number of genes whose protein products modify lipopolysaccharide (LPS). The LPS is modified during transport to the bacterial outer membrane (OM). A subset of PmrAB-mediated LPS modifications consists of the addition of phosphoethanolamine (pEtN) to lipid A by PmrC and to the core by CptA. In
Salmonella enterica
, pEtN modifications have been associated with resistance to polymyxin B and to excess iron. To investigate putative functions of pEtN modifications in
Citrobacter rodentium
, Δ
pmrAB
, Δ
pmrC
, Δ
cptA
, and Δ
pmrC
Δ
cptA
deletion mutants were constructed. Compared to the wild type, most mutant strains were found to be more susceptible to antibiotics that must diffuse across the LPS layer of the OM. All mutant strains also showed increased influx rates of ethidium dye across their OM, suggesting that PmrAB-regulated pEtN modifications affect OM permeability. This was confirmed by increased partitioning of the fluorescent dye 1-
N
-phenylnaphthylamine (NPN) into the OM phospholipid layer of the mutant strains. In addition, substantial release of periplasmic β-lactamase was observed for the Δ
pmrAB
and Δ
pmrC
Δ
cptA
strains, indicating a loss of OM integrity. This study attributes a new role for PmrAB-mediated pEtN LPS modifications in the maintenance of
C. rodentium
OM integrity.
Promoting tobacco cessation via the workplace: opportunities for improvement: Table 1
Authors: Hughes M Courtney , Yette Emily M , Hannon Peggy A , Harris Jeffrey R , Tran Nguyet M , Reid Terry R 
Published: March 2011

IntroductionLittle research exists on the prevalence of evidence-based tobacco cessation practices in workplaces, employer promotion of state-sponsored quitlines and predictors of these practices.MethodsCross-sectional analysis of the 2008 Healthy Worksite Survey, a telephone survey administered to Washington employers with 50 or more employees (n=693). The objectives were to describe workplaces' implementation of evidence-based tobacco cessation practices and identify key predictors of implementation in order to highlight opportunities for interventions.ResultsAmong these employers, 38.6% promoted quitting tobacco, and 33.8% offered insurance coverage for cessation medications and counselling, 27.5% referred no-smoking violators to cessation services, and 5.7% included the state-sponsored quitline in health promotion messages. Larger workplaces and workplaces with a wellness staff, committee or coordinator had greater insurance coverage for tobacco cessation, communications promoting tobacco cessation, and promotion of the state-sponsored quitline (p<0.01). Workplaces with a wellness staff, committee or coordinator referred more violators of no-smoking policies to cessation services (p<0.01).ConclusionsIn Washington State workplaces do little to promote tobacco cessation by their employees. The lack of tobacco cessation promoting practices at small businesses, restaurants and bars, and businesses without wellness personnel indicates an opportunity for finding and reaching current smokers at businesses with limited resources. By adopting inexpensive prevention efforts, such as promoting the state-sponsored tobacco cessation quitline, employers can help employees quit smoking and, thereby, assist in improving employee health and lower medical costs.
Retrospective study of scintigraphic and radiological findings in 21 cases of enostosis‐like lesions in horses
Authors: O'Neill H. D. , Bladon B. M. 
Published: March 2011

Records of horses admitted to a veterinary surgery in the UK for lameness investigation during 2000 to 2008 were reviewed. Twenty‐one horses were identified with both scintigraphic and radiological evidence of enostosis‐like lesions (ELLs), in which 68 individual foci of increased radiopharmaceutical uptake were confirmed in 57 long bones. The presenting lameness was attributed to ELLs in 15 of 21 (71 per cent) horses; the remainder were thought to be incidental findings. Five horses were subjected to a repeat examination, four of which showed the occurrence of new lesions in the same or different limbs. Hindlimbs had significantly more lesions than forelimbs, but there was no difference between the right and left limbs. All 18 horses for which follow‐up information was available were treated conservatively and returned to soundness after a variable period of time. Following ELL resolution, thoroughbred horses performed at a similar level to that before investigation and diagnosis.
MRI of Coronary Wall Remodeling in a Swine Model of Coronary Injury Using an Elastin-Binding Contrast Agent
Authors: von Bary Christian , Makowski Marcus , Preissel Anne , Keithahn Alexandra , Warley Alice , Spuentrup Elmar , Buecker Arno , Lazewatsky Joel , Cesati Richard , Onthank David , Schickl Nikolaus , Schachoff Sylvia , Hausleiter Jörg , Schömig Albert , Schwaiger Markus , Robinson Simon , Botnar René 
Published: March 2011

Background—
The extracellular matrix (ECM) plays an important role in the pathogenesis of atherosclerosis and in-stent restenosis. Elastin is an essential component of the ECM. ECM degradation can lead to plaque destabilization, whereas enhanced synthesis typically leads to vessel wall remodeling resulting in arterial stenosis or in-stent restenosis after stent implantation. The objective of this study was to demonstrate the feasibility of MRI of vascular remodeling using a novel elastin-binding contrast agent (BMS-753951).

Methods and Results—

Coronary injury was induced in 6 pigs by endothelial denudation and stent placement. At day 28, delayed-enhancement MRI coronary vessel wall imaging was performed before and after injection of gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA). Two days later, DE-MRI was repeated after administration of BMS-753951. Contrast-to-noise-ratio and areas of enhancement were determined. Delayed-enhancement MRI with BMS-753951 caused strong enhancement of the aortic, pulmonary artery, and injured coronary artery walls, whereas Gd-DTPA did not. Delayed-enhancement MRI of the stented coronary artery with BMS-753951 yielded a 3-fold higher contrast-to-noise-ratio when compared with the balloon-injured and control coronary artery (21±6 versus 7±3 versus 6±4;
P
<0.001). The area of enhancement correlated well with the area of remodeling obtained from histological data (
R
2
=0.86,
P
<0.05).

Conclusions—
We demonstrate the noninvasive detection and quantification of vascular remodeling in an animal model of coronary vessel wall injury using an elastin-specific MR contrast agent. This novel approach may be useful for the assessment of coronary vessel wall remodeling in patients with suspected coronary artery disease. Further studies in atherosclerotic animal models and degenerative ECM disease are now warranted.
Origins and Levels of Seasonal Forecast Skill for Sea Ice in Hudson Bay Using Canonical Correlation Analysis
Authors: Tivy Adrienne , Howell Stephen E. L. , Alt Bea , Yackel John J. , Carrieres Thomas 
Published: March 2011

Abstract
Canonical correlation analysis (CCA) is used to estimate the levels and sources of seasonal forecast skill for July ice concentration in Hudson Bay over the 1971–2005 period. July is an important transition month in the seasonal cycle of sea ice in Hudson Bay because it is the month when the sea ice clears enough to allow the first passage of ships to the Port of Churchill. Sea surface temperature (quasi global, North Atlantic, and North Pacific), Northern Hemisphere 500-mb geopotential height (z500), sea level pressure (SLP), and regional surface air temperature (SAT) are tested as predictors at 3-, 6-, and 9-month lead times. The model with the highest skill has three predictors—fall North Atlantic SST, fall z500, and fall SAT—and significant tercile forecast skill covering 61% of the Hudson Bay region.
The highest skill for a single-predictor model is from fall North Atlantic SST (6-month lead). Fall SST explains 69% of the variance in July ice concentration in Hudson Bay and a possible atmospheric link that accounts for the lagged relationship is presented. CCA diagnostics suggest that changes in the subpolar North Atlantic gyre and the Atlantic multidecadal oscillation (AMO), reflected in sea surface temperature, precedes a deepening/weakening of the winter upper-air ridge northwest of Hudson Bay. Changes in the height of the ridge are reflected in the strength of the winter northwesterly winds over Hudson Bay that have a direct impact on the winter ice thickness distribution; anomalies in winter ice severity are later reflected in the pattern and timing of spring breakup. July ice concentration in Hudson Bay has declined by approximately 20% per decade between 1979 and 2007, and the hypothesized link to the AMO may help explain this significant loss of ice.
Murine Ciliotoxicity and Rabbit Sinus Mucosal Healing by Polyhydrated Ionogen
Authors: DePoortere David , Kofonow Jennifer M. , Chen Bei , Chiu Alexander G. , Cohen Noam A. 
Published: March 2011

ObjectivesDetermine the toxicity and efficacy of a novel antiprotease topical irrigation, polyhydrated ionogen (PHI) ± MgBr2, in improving sinonasal remucosalization following surgery.Study DesignBlinded, randomized controlled study.SettingAcademic.Subjects and MethodsCiliary beat frequency (CBF) of murine nasal septal explants was continuously recorded before and after addition of PHI solution to asses for ciliotoxicity. To evaluate for efficacy in remucosalization, 9 New Zealand white rabbits underwent bilateral medial‐wall maxillary mucosal stripping followed by placement of an indwelling irrigation catheter. In a randomized fashion one side received 3 mL of normal saline (NS) daily, whereas the contralateral side received PHI ± MgBr2. Following a 14‐day therapeutic trial, remucosalization was assessed by hematoxylin and eosin staining and immunohistochemistry for β‐tubulin, a marker of cilia. A semiquantitative grading of ciliated remucosalization was applied with a chi‐square test to compare the saline with the PHI ± MgBr2 treatment.ResultsSafety evaluation of the PHI solutions demonstrated no evidence of ciliotoxicity. Histologic semiquantitative analysis of maxillary sinus remucosalization demonstrated significantly more ciliated epithelium (>60%) in the majority of PHI (n = 4) and PHI with MgBr2 (n = 5) treatment compared with the saline treatment (<30%) (n = 9). This was confirmed with immunohistochemical staining for type IV β‐tubulin a marker of respiratory cilia.ConclusionsSuccess of functional endoscopic sinus surgery depends on restoration of normal mucociliary clearance. Topical PHI application has previously been demonstrated to significantly increase dermal wound healing. PHI solution is not ciliotoxic, and daily topical PHI or PHI MgBr2 irrigation enhances ciliated remucosalization compared with saline.