bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic Typing, Based on the 56-Kilodalton Type-Specific Antigen Gene, of Orientia tsutsugamushi Strains Isolated from Chiggers Collected from Wild-Caught Rodents in Taiwan
Authors: Lin Pey-Ru , Tsai Hui-Ping , Tsui Pei-Yi , Weng Ming-Hui , Kuo Ming-Der , Lin Hung-Chi , Chen Kuo-Ching , Ji Dar-Der , Chu Der-Ming , Liu Wen-Tssann 
Published: March 2011

ABSTRACTOrientia tsutsugamushiis the etiological agent of scrub typhus, a mite-borne, febrile illness that occurs in the Asia-Pacific region. We conducted strain characterization ofO. tsutsugamushiisolates from chiggers obtained from rodents based the nucleotide sequence of the 56-kDa outer membrane protein gene. With the use of PCR, a total of 68 DNA sequences of 56-kDa antigen genes were amplified. Phylogenetic analysis revealed that there were at least six definable clusters among the 68 isolates: 37% Karp-related strains (25/68), 27% TA763 strains (18/68), 12% JG-related strains (8/68), 19% Kato-related strains (13/68), 4% divergent strains (3/68), and 1% representing a Gilliam prototype strain (1/68). Overall, theO. tsutsugamushigenotypes exhibited a high degree of diversity, similar to that seen in strains from the rest of the areas where scrub typhus is endemic. Moreover, the 56-kDa protein sequence similarity betweenO. tsutsugamushiisolates from mites and those from human patients (H. Y. Lu et al., Am. J. Trop. Med. Hyg. 83:658-663, 2010) were striking, thus highlighting potential risk factors for this emerging zoonotic disease.
Corynebacterium glutamicum Tailored for Efficient Isobutanol Production
Authors: Blombach Bastian , Riester Tanja , Wieschalka Stefan , Ziert Christian , Youn Jung-Won , Wendisch Volker F. , Eikmanns Bernhard J. 
Published: March 2011

ABSTRACT

We recently engineered
Corynebacterium glutamicum
for aerobic production of 2-ketoisovalerate by inactivation of the pyruvate dehydrogenase complex, pyruvate:quinone oxidoreductase, transaminase B, and additional overexpression of the
ilvBNCD
genes, encoding acetohydroxyacid synthase, acetohydroxyacid isomeroreductase, and dihydroxyacid dehydratase. Based on this strain, we engineered
C. glutamicum
for the production of isobutanol from glucose under oxygen deprivation conditions by inactivation of
l
-lactate and malate dehydrogenases, implementation of ketoacid decarboxylase from
Lactococcus lactis
, alcohol dehydrogenase 2 (ADH2) from
Saccharomyces cerevisiae
, and expression of the
pntAB
transhydrogenase genes from
Escherichia coli
. The resulting strain produced isobutanol with a substrate-specific yield (Y
P/S
) of 0.60 ± 0.02 mol per mol of glucose. Interestingly, a chromosomally encoded alcohol dehydrogenase rather than the plasmid-encoded ADH2 from
S. cerevisiae
was involved in isobutanol formation with
C. glutamicum
, and overexpression of the corresponding
adhA
gene increased the Y
P/S
to 0.77 ± 0.01 mol of isobutanol per mol of glucose. Inactivation of the malic enzyme significantly reduced the Y
P/S
, indicating that the metabolic cycle consisting of pyruvate and/or phosphoenolpyruvate carboxylase, malate dehydrogenase, and malic enzyme is responsible for the conversion of NADH+H
+
to NADPH+H
+
. In fed-batch fermentations with an aerobic growth phase and an oxygen-depleted production phase, the most promising strain,
C. glutamicum
Δ
aceE
Δ
pqo
Δ
ilvE
Δ
ldhA
Δ
mdh
(pJC4
ilvBNCD-pntAB
)(pBB1
kivd-adhA
), produced about 175 mM isobutanol, with a volumetric productivity of 4.4 mM h
−1
, and showed an overall Y
P/S
of about 0.48 mol per mol of glucose in the production phase.
Independent Emergence of Yersinia ruckeri Biotype 2 in the United States and Europe
Authors: Welch Timothy J. , Verner-Jeffreys David W. , Dalsgaard Inger , Wiklund Thomas , Evenhuis Jason P. , Garcia Cabrera Jose A. , Hinshaw Jeffrey M. , Drennan John D. , LaPatra Scott E. 
Published: March 2011

ABSTRACT

Biotype 2 (BT2) variants of the bacterium
Yersinia ruckeri
are an increasing disease problem in U.S. and European aquaculture and have been characterized as serovar 1 isolates that lack both peritrichous flagella and secreted phospholipase activity. The emergence of this biotype has been associated with an increased frequency of enteric redmouth disease (ERM) outbreaks in previously vaccinated salmonid fish. In this study, four independent specific natural mutations that cause the loss of both motility and secreted lipase activity were identified in BT2 strains from the United States, United Kingdom, and mainland Europe. Each of these was a unique mutation in either
fliR
,
flhA
, or
flhB
, all of which are genes predicted to encode essential components of the flagellar secretion apparatus. Our results demonstrate the existence of independent mutations leading to the BT2 phenotype; thus, this phenotype has emerged separately at least four times. In addition, BT2 strains from the United Kingdom were shown to have the same mutant allele found in U.S. BT2 strains, suggesting a common origin of this BT2 lineage. This differentiation of distinct BT2 lineages is of critical importance for the development and validation of alternative vaccines or other treatment strategies intended for the control of BT2 strains.
Strain-Dependent Norovirus Bioaccumulation in Oysters
Authors: Maalouf Haifa , Schaeffer Julien , Parnaudeau Sylvain , Le Pendu Jacques , Atmar Robert L. , Crawford Sue E. , Le Guyader Françoise S. 
Published: March 2011

ABSTRACTNoroviruses (NoVs) are the main agents of gastroenteritis in humans and the primary pathogens of shellfish-related outbreaks. Some NoV strains bind to shellfish tissues by using carbohydrate structures similar to their human ligands, leading to the hypothesis that such ligands may influence bioaccumulation. This study compares the bioaccumulation efficiencies and tissue distributions in oysters (Crassostrea gigas) of three strains from the two principal human norovirus genogroups. Clear differences between strains were observed. The GI.1 strain was the most efficiently concentrated strain. Bioaccumulation specifically occurred in digestive tissues in a dose-dependent manner, and its efficiency paralleled ligand expression, which was highest during the cold months. In comparison, the GII.4 strain was very poorly bioaccumulated and was recovered in almost all tissues without seasonal influence. The GII.3 strain presented an intermediate behavior, without seasonal effect and with less bioaccumulation efficiency than that of the GI.1 strain during the cold months. In addition, the GII.3 strain was transiently concentrated in gills and mantle before being almost specifically accumulated in digestive tissues. Carbohydrate ligand specificities of the strains at least partly explain the strain-dependent bioaccumulation characteristics. In particular, binding to the digestive-tube-specific ligand should contribute to bioaccumulation, whereas we hypothesize that binding to the sialic acid-containing ligand present in all tissues would contribute to retain virus particles in the gills or mantle and lead to rapid destruction.
Uncovering a Role for the Tail of the Dictyostelium discoideum SadA Protein in Cell-Substrate Adhesion
Authors: Kowal Anthony S. , Chisholm Rex L. 
Published: March 2011

ABSTRACTPrevious work from our laboratory showed that theDictyostelium discoideumSadA protein plays a central role in cell-substrate adhesion. SadA null cells exhibit a loss of adhesion, a disrupted actin cytoskeleton, and a cytokinesis defect. How SadA mediates these phenotypes is unknown. This work addresses the mechanism of SadA function, demonstrating an important role for the C-terminal cytoplasmic tail in SadA function. We found that a SadA tailless mutant was unable to rescue thesadAadhesion deficiency, and overexpression of the SadA tail domain reduced adhesion in wild-type cells. We also show that SadA is closely associated with the actin cytoskeleton. Mutagenesis studies suggested that four serine residues in the tail, S924/S925 and S940/S941, may regulate association of SadA with the actin cytoskeleton. GlutathioneS-transferase pull-down assays identified at least one likely interaction partner of the SadA tail, cortexillin I, a known actin bundling protein. Thus, our data demonstrate an important role for the carboxy-terminal cytoplasmic tail in SadA function and strongly suggest that a phosphorylation event in this tail regulates an interaction with cortexillin I. Based on our data, we propose a model for the function of SadA.
Mimicry of the Pathogenic Mycobacterium VacuoleIn VitroElicits the Bacterial Intracellular Phenotype, Including Early-Onset Macrophage Death
Authors: Early Julie , Bermudez Luiz E. 
Published: March 2011

ABSTRACTMycobacterium aviumcomplex (MAC) within macrophages undergoes a phenotype change that allows for more efficient entry into surrounding host cells. We hypothesized that, by developing anin vitrosystem resembling the intravacuolar environment, one could generate insights into the mycobacterial intracellular phenotype. MAC was incubated in “elemental mixtures” that reproduce metal concentrations and pH in the vacuoles at different time points and then used to infect fresh macrophages. Incubation of MAC with the mixture corresponding to the vacuole environment 24 h postinfection infected macrophages at a significantly higher rate than bacteria that were incubated in Middlebrook 7H9 broth. Uptake occurred by macropinocytosis, similar to the uptake of bacteria passed through macrophages. Genes reported to be upregulated in intracellular bacteria, such asMav1365,Mav2409,Mav4487, andMav0996, were upregulated in MAC incubated in the 24-h elemental mixture. Like MAC obtained from macrophages, the vacuoles of bacteria from the 24-h elemental mixture were more likely to contain lysosome-associated membrane protein 1 (LAMP-1). A stepwise reduction scheme of the 24-h elemental mixture indicated that incubation in physiologically relevant concentrations of potassium chloride, calcium chloride, and manganese chloride was sufficient to induce characteristics of the intracellular phenotype. It was demonstrated that bacteria harboring the intracellular phenotype induced early-onset macrophage death more efficiently than bacteria grown in broth. This new trace elemental mixture mimicking the condition of the vacuole at different time points has the potential to become an effective laboratory tool for the study of the MAC andMycobacterium tuberculosisdisease process, increasing the understanding of the interaction with macrophages.
Molecular Basis of Immunity to Rickettsial Infection Conferred through Outer Membrane Protein B
Authors: Chan Yvonne Gar-Yun , Riley Sean Phillip , Chen Emily , Martinez Juan José 
Published: March 2011

ABSTRACTPathogenic rickettsiae are the causative agents of Rocky Mountain spotted fever, typhus, and other human diseases with high mortality and an important impact on society. Although survivors of rickettsial infections are considered immune to disease, the molecular basis of this immunity or the identification of protective antigens that enable vaccine development was hitherto not known. By exploring the molecular pathogenesis ofRickettsia conorii, the agent of Mediterranean spotted fever, we report here that the autotransporter protein, rickettsial outer membrane protein B (rOmpB), constitutes a protective antigen for this group of pathogens. A recombinant, purified rOmpB passenger domain fragment comprised of amino acids 36 to 1334 is sufficient to elicit humoral immune responses that protect animals against lethal disease. Protective immunity requires folded antigen and production of antibodies that recognize conformational epitopes on the rickettsial surface. Monoclonal antibodies (MAbs) 5C7.27 and 5C7.31, which specifically recognize a conformation present in the folded, intact rOmpB passenger domain, are sufficient to confer immunityin vivo. Analysesin vitroindicate this protection involves a mechanism of complement-mediated killing in mammalian blood, a means of rickettsial clearance that has not been previously described. Considering the evolutionary conservation of rOmpB and its crucial contribution to bacterial invasion of host cells, we propose that rOmpB antibody-mediated killing confers immunity to rickettsial infection.
Genome Sequences of the High-Acetic Acid-Resistant Bacteria Gluconacetobacter europaeus LMG 18890
T
and G. europaeus LMG 18494 (Reference Strains), G. europaeus 5P3, and Gluconacetobacter oboediens 174Bp2 (Isolated from Vinegar)
Authors: Andrés-Barrao Cristina , Falquet Laurent , Calderon-Copete Sandra P. , Descombes Patrick , Ortega Pérez Ruben , Barja François 
Published: March 2011

ABSTRACT

Bacteria of the genus
Gluconacetobacter
are usually involved in the industrial production of vinegars with high acetic acid concentrations. We describe here the genome sequence of three
Gluconacetobacter europaeus
strains, a very common bacterial species from industrial fermentors, as well as of a
Gluconacetobacter oboediens
strain.
Different approaches to obtaining consent for follow-up result in biased samples
Authors: Pless Barry , Hagel Brent , Zhang Xun , Magdalinos Helen 
Published: March 2011

BackgroundMany injury studies use samples of hospital patients. If a study requires further contact, consent is usually required but the sample may be biased if many fail to consent.ObjectiveTo determine whether wording requiring ‘active’ consent resulted in more refusals than wording that was ‘passive’—that is, where consent is implied in the absence of direct refusal.MethodsSubjects were injured children seen in the emergency departments in five hospitals where the Canadian Hospital Injury Reporting and Prevention Program (CHIRPP) operates. For CHIRPP, parents or older children complete a one-page questionnaire to describe the injury; one question seeks consent to follow-up for research. Three of the hospitals use passive wording for this question and two use active wording. All cases where CHIRPP coordinators completed forms using the medical record were treated as refusals. It was hypothesised that there would be a significant association between the form of wording (active or passive) and the rate of consent, and that this association would be affected by socio-demographic and clinical variables.ResultsOn average, 64.5% of parents gave consent for follow-up at hospitals using passive consent wording versus 42% where active consent wording was used. Passive wording consistently yielded a higher percentage of consents for all variables. The differences were greater than 5% for families living in census tracts with low median household incomes and greater than 10% for those age 15–19 years. For parent completed forms the adjusted OR for active wording was 0.48 (95% CI 0.43 to 0.54).ConclusionCaution is needed when interpreting results from studies using hospital samples, especially when wording of consent for follow-up requires direct affirmation.
Are we homogenising risk factors for public health surveillance? Variability in severe injuries on First Nations reserves in British Columbia, 2001–5
Authors: Bell Nathaniel , Schuurman Nadine , Hameed S Morad , Caron Nadine 
Published: March 2011

BackgroundAboriginal Canadians are considered to be at increased risk of injury. The de facto standard for measuring injury risk factors among Aboriginal Canadians is to compare hospitalisation and mortality against non-Aboriginal Canadians, but this may be too broad an approach for injury prevention and public health if it over-generalises injury risk.MethodsData from this study are drawn from the 2001–5 British Columbia Trauma Registry and British Columbia Coroner's Service. Observed and expected hospitalisations and mortality rates on reserves were assessed against three different spatial aggregations of non-reserve reference populations. Data analysis was conducted in a geographical information system using a Poisson probability map.ResultsA total of 47 (9.6%) of 487 reserves in British Columbia contained at least one person who was hospitalised or died as a result of serious injury during the study period. Of these, two reserve populations represented 20% (n=19) of all injury morbidity events and 30% (n=22) of all mortality events.ConclusionEvidence from this study suggests that community-based rather than provincial-based injury reporting is less likely to over-generalise the burden of injury among Aboriginal communities. Community-based surveillance enables researchers to identify why severe unintentional and intentional injury continues to burden some communities but not others and avoids the potentially demoralising and stigmatising effects of current surveillance practices.
Predictive factors for ciclosporin-associated nephrotoxicity in children with minimal change nephrotic syndrome
Authors: Kim Ji Hong , Park Se Jin , Yoon So Jin , Lim Beom Jin , Jeong Hyeon Joo , Lee Jae Seung , Kim Pyung Kil , Shin Jae Il 
Published: March 2011

AimsTo identify the predictive factors for ciclosporin A (CyA)-associated nephrotoxicity (CAN) in children with minimal change nephrotic syndrome (MCNS).MethodsThe clinical and laboratory findings of 58 children (median age 3.2 years, range 1.1–13.1 years, male:female 48:10) with MCNS who were treated with CyA from 1992 to 2002 were analysed retrospectively. Forty-eight (83%) of them were steroid dependent and 10 (17%) were steroid resistant. The starting dose of CyA was 5 mg/kg per day, and the desired drug level was kept at 100–200 ng/ml. Serial renal biopsies were performed before and after CyA therapy.ResultsTwenty-two patients (38%) had CAN (group I) and 36 (62%) did not (group II). There were no differences in the age at onset, sex, initial response to steroids, duration of CyA therapy and relapse rates. However, the median CyA trough levels were significantly higher in group I than in group II (218.0±15.2 vs 171.8±6.7 ng/ml, p=0.01). Changes in creatinine clearance were more decreased in group I than in group II (−39.4±8.2 vs 2.7±4.3 ml/min per 1.73 m2, p<0.0001). Multiple logistic regression analysis also revealed the median CyA trough level was an independent risk factor for the development of CAN (OR 1.025, 95% CI 1.007 to 1.044, p=0.007).ConclusionsThe median CyA trough level was an independent and significant risk factor for the development of CAN in children with MCNS receiving moderate-dose CyA.
Mast cell densities in bronchial biopsies and small airways are related
Authors: Carroll M L , Carroll N G , Gundersen H J , James A L 
Published: March 2011

IntroductionThe study sought to determine whether mast cell counts in endobronchial biopsies of large airways are related to mast cell counts in the small airways.MethodsLungs, obtained postmortem from 10 subjects who had died of non-respiratory causes, were fixed in inflation. Mast cell densities (cells/mm3), determined with an optical disector, were compared on histological sections (30 μm thick) of biopsies and small airways stained with human anti-mast cell tryptase.ResultsMean mast cell density over the inner airway wall in biopsies was significantly related to mean mast cell density over the total airway wall in the small airways (r=∼0.80, p<0.01). A minimum of three biopsies per case was required to demonstrate this relationship. Within relevant count areas, mast cell density was about 1.6-fold higher in the small airways than in the biopsies.ConclusionsThese findings suggest that when mean counts from at least three biopsies per case are used, intersubject comparisons of mast cell density in the inner airway wall in endobronchial biopsies reflect intersubject comparisons of mast cell density over the total airway wall in small airways. This is despite the observation that mast cell densities are generally higher in the small airways.
The attribution of work environment in explaining gender differences in long-term sickness absence: results from the prospective DREAM study: Table 1
Authors: Labriola Merete , Holte Kari Anne , Christensen Karl Bang , Feveile Helene , Alexanderson Kristina , Lund Thomas 
Published: March 2011

ObjectivesTo identify differences in risk of long-term sickness absence between female and male employees in Denmark and to examine to what extent differences could be explained by work environment factors.MethodsA cohort of 5026 employees (49.1% women, mean age 40.4 years; 50.9% men, mean age 40.2 years) was interviewed in 2000 regarding gender, age, family status, socio-economic position and psychosocial and physical work environment factors. The participants were followed for 18 months in order to assess their incidence of long-term sickness absence exceeding 8 consecutive weeks.Results298 workers (5.9%) received sickness absence compensation for 8 weeks or more. Women had an excess risk of 37% compared to men, when adjusting for age, family status and socio-economic position. Physical work environment exposures could not explain this difference, whereas differences in psychosocial work environment exposures explained 32% of the differences in risk of long-term sickness absence between men and women, causing the effect of gender to become statistically insignificant. The combined effect of physical and psychosocial factors was similar, explaining 30% of the gender difference.ConclusionDifferences in psychosocial work environments in terms of emotional demands, reward at work, management quality and role conflicts, explained roughly 30% of women's excess long-term sickness absence risk. Assuming women and men had identical working conditions would leave the larger part of the gender difference in long-term sickness absence from work unexplained.
Enhancement of systemic and sputum granulocyte response to inhaled endotoxin in people with the GSTM1 null genotype: Figure 1
Authors: Dillon Madeline A , Harris Bradford , Hernandez Michelle L , Zou Baiming , Reed William , Bromberg Philip A , Devlin Robert B , Diaz-Sanchez David , Kleeberger Steven , Zhou Haibo , Lay John C , Alexis Neil E , Peden David B 
Published: March 2011

ObjectiveTo determine if the GSTM1 null genotype is a risk factor for increased inflammatory response to inhaled endotoxin.Methods35 volunteers who had undergone inhalation challenge with a 20 000 endotoxin unit dose of Clinical Center Reference Endotoxin (CCRE) were genotyped for the GSTM1 null polymorphism. Parameters of airway and systemic inflammation observed before and after challenge were compared in GSTM1 null (n=17) and GSTM1 (n=18) sufficient volunteers.ResultsGSTM1 null volunteers had significantly increased circulating white blood cells (WBCs), polymorphonuclear neutrophils (PMNs), platelets and sputum PMNs (% sputum PMNs and PMNs/mg sputum) after CCRE challenge. GSTM1 sufficient volunteers had significant, but lower increases in circulating WBCs, PMNs and % sputum PMNs, and no increase in platelets or PMNs/mg sputum. Linear regression analysis adjusted for baseline values of the entire cohort revealed that the GSTM1 null genotype significantly increased circulating WBCs, platelets and % sputum PMNs after challenge.ConclusionThese data support the hypothesis that the GSTM1 null genotype is a risk factor for increased acute respiratory and systemic inflammatory response to inhaled CCRE. These data are consistent with other observations that the GSTM1 null genotype is associated with increased respiratory, systemic and cardiovascular effects linked to ambient air particulate matter exposure and indicate that the GSTM1 null genotype should be considered a risk factor for adverse health effects associated with exposure to environmental endotoxin.