bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cdv‐based cell division and cell cycle organization in the thaumarchaeon Nitrosopumilus maritimus
Authors: Pelve Erik A. , Lindås Ann‐Christin , Martens‐Habbena Willm , de la Torre José R. , Stahl David A. , Bernander Rolf 
Published: September 2011

SummaryCell division is mediated by different mechanisms in different evolutionary lineages. While bacteria and euryarchaea utilize an FtsZ‐based mechanism, most crenarchaea divide using the Cdv system, related to the eukaryotic ESCRT‐III machinery. Intriguingly, thaumarchaeal genomes encode both FtsZ and Cdv protein homologues, raising the question of their division mode. Here, we provide evidence indicating that Cdv is the primary division system in the thaumarchaeon Nitrosopumilus maritimus. We also show that the cell cycle is differently organized as compared to hyperthermophilic crenarchaea, with a longer pre‐replication phase and a shorter post‐replication stage. In particular, the time required for chromosome replication is remarkably extensive, 15–18 h, indicating a low replication rate. Further, replication did not continue to termination in a significant fraction of N. maritimus cell populations following substrate depletion. Both the low replication speed and the propensity for replication arrest are likely to represent adaptations to extremely oligotrophic environments. The results demonstrate that thaumarchaea, crenarchaea and euryarchaea display differences not only regarding phylogenetic affiliations and gene content, but also in fundamental cellular and physiological characteristics. The findings also have implications for evolutionary issues concerning the last archaeal common ancestor and the relationship between archaea and eukaryotes.
An SMC ATPase mutant disrupts chromosome segregation in Caulobacter
Authors: Schwartz Monica A. , Shapiro Lucy 
Published: September 2011

SummaryAccurate replication and segregation of the bacterial genome are essential for cell cycle progression. We have identified a single amino acid substitution in the Caulobacter structural maintenance of chromosomes (SMC) protein that disrupts chromosome segregation and cell division. The E1076Q point mutation in the SMC ATPase domain caused a dominant‐negative phenotype in which DNA replication was able to proceed, but duplicated parS centromeres, normally found at opposite cell poles, remained at one pole. The cellular positions of other chromosomal loci were in the wild‐type order relative to the parS centromere, but chromosomes remained unsegregated and appeared to be stacked upon one another. Purified SMC‐E1076Q was deficient in ATP hydrolysis and exhibited abnormally stable binding to DNA. We propose that SMC spuriously links the duplicated chromosome immediately after passage of the replication fork. In wild‐type cells, ATP hydrolysis opens the SMC dimer, freeing one chromosome to segregate to the opposite pole. The loss of ATP hydrolysis causes the SMC‐E1076Q dimer to remain bound to both chromosomes, inhibiting segregation.
Bacillus anthracis virulence regulator AtxA: oligomeric state, function and CO2‐signalling
Authors: Hammerstrom Troy G. , Roh Jung Hyeob , Nikonowicz Edward P. , Koehler Theresa M. 
Published: September 2011

SummaryAtxA, a unique regulatory protein of unknown molecular function, positively controls expression of the major virulence genes of Bacillus anthracis. The 475 amino acid sequence of AtxA reveals DNA binding motifs and regions similar to proteins associated with the phosphoenolpyruvate: carbohydrate phosphotransferase system (PTS). We used strains producing native and functional epitope‐tagged AtxA proteins to examine protein–protein interactions in cell lysates and in solutions of purified protein. Co‐affinity purification, non‐denaturing polyacrylamide gel electrophoresis and bis(maleimido)hexane (BMH) cross‐linking experiments revealed AtxA homo‐multimers. Dimers were the most abundant species. BMH cross‐links available cysteines within 13 Å. To localize interaction sites, six AtxA mutants containing distinct Cys→Ser substitutions were tested for multimerization and cross‐linking. All mutants multimerized, but one mutation, C402S, prevented cross‐linking. Thus, BMH uses C402 to make the inter‐molecular bond between AtxA proteins, but C402 is not required for protein–protein interaction. C402 is in a region bearing amino acid similarity to Enzyme IIB proteins of the PTS. The AtxA EIIB motif may function in protein oligomerization. Finally, cultures grown with elevated CO2/bicarbonate exhibited increased AtxA dimer/monomer ratios and increased AtxA activity, relative to cultures grown without added CO2/bicarbonate, suggesting that this host‐associated signal enhances AtxA function by shifting the dimer/monomer equilibrium towards the dimeric state.
The phytochelatin transporters AtABCC1 and AtABCC2 mediate tolerance to cadmium and mercury
Authors: Park Jiyoung , Song Won‐Yong , Ko Donghwi , Eom Yujin , Hansen Thomas H. , Schiller Michaela , Lee Tai Gyu , Martinoia Enrico , Lee Youngsook 
Published: September 2011

SummaryHeavy metals such as cadmium (Cd) and mercury (Hg) are toxic pollutants that are detrimental to living organisms. Plants employ a two‐step mechanism to detoxify toxic ions. First, phytochelatins bind to the toxic ion, and then the metal–phytochelatin complex is sequestered in the vacuole. Two ABCC‐type transporters, AtABCC1 and AtABCC2, that play a key role in arsenic detoxification, have recently been identified in Arabidopsis thaliana. However, it is unclear whether these transporters are also implicated in phytochelatin‐dependent detoxification of other heavy metals such as Cd(II) and Hg(II). Here, we show that atabcc1 single or atabcc1 atabcc2 double knockout mutants exhibit a hypersensitive phenotype in the presence of Cd(II) and Hg(II). Microscopic analysis using a Cd‐sensitive probe revealed that Cd is mostly located in the cytosol of protoplasts of the double mutant, whereas it occurs mainly in the vacuole of wild‐type cells. This suggests that the two ABCC transporters are important for vacuolar sequestration of Cd. Heterologous expression of the transporters in Saccharomyces cerevisiae confirmed their role in heavy metal tolerance. Over‐expression of AtABCC1 in Arabidopsis resulted in enhanced Cd(II) tolerance and accumulation. Together, these results demonstrate that AtABCC1 and AtABCC2 are important vacuolar transporters that confer tolerance to cadmium and mercury, in addition to their role in arsenic detoxification. These transporters provide useful tools for genetic engineering of plants with enhanced metal tolerance and accumulation, which are desirable characteristics for phytoremediation.
Thrombocytopenia at birth in neonates with red cell alloimmune haemolytic disease
Authors: Rath M. E. A. , Smits‐Wintjens V. E. H. J. , Oepkes D. , van Zwet E. W. , van Kamp I. L. , Brand A. , Walther F. J. , Lopriore E. 
Published: September 2011

Objective  To evaluate the incidence and severity of and risk factors for thrombocytopenia at birth in neonates with red cell alloimmunization.Study design  All neonates with haemolytic disease of the foetus/newborn (HDFN) due to red cell alloimmunization admitted to our centre between January 2000 and September 2010 were included in this retrospective study. We measured platelet counts at birth and determined the incidence of thrombocytopenia (platelet count < 150 × 109/l) and severe thrombocytopenia (platelet count < 50 × 109/l). Risk factors for thrombocytopenia at birth were evaluated.Results  Thrombocytopenia was present in 26% (94/362) of included neonates with HDFN at birth. Severe thrombocytopenia was found in 6% (20/362) of neonates. Three risk factors were found to be independently associated with thrombocytopenia at birth: treatment with intrauterine red cell transfusion (IUT) (OR 3·32, 95% CI 1·67–6·60, P = 0·001), small for gestational age (SGA) below the 10th percentile (OR 3·32, 95% CI 1·25–8·80, P = 0·016) and lower gestational age at birth (OR 1·22/week, 95% CI 1·02–1·44, P = 0·025).Conclusions  Thrombocytopenia at birth occurs in 26% of neonates with HDFN due to red cell alloimmunization and is independently associated with IUT treatment, SGA and lower gestational age at birth.
Adhesive interaction between peripheral blood mononuclear cells and activated platelets in the presence of anti‐human leukocyte antigen Class I alloantibody causes production of IL‐1β and IL‐8
Authors: Takahashi D. , Fujihara M. , Azuma H. , Wakamoto S. , Sato S. , Kato T. , Ikeda H. 
Published: September 2011

Background:  Activated platelets form heterogeneous aggregates of platelets and monocytes, which are involved in a variety of inflammatory disorders. Some anti‐human leukocyte antigen (HLA) Class I antibodies have been shown to activate platelets.Materials and Methods:  Human leukocyte antigen‐A2‐positive or HLA‐A2‐negative platelets were incubated with HLA‐A2‐negative peripheral blood mononuclear cells (PBMNCs) in the presence of anti‐HLA‐A2 serum at 37°C. The binding of platelets to monocytes was analysed by flow cytometry. The levels of IL‐1 β and IL‐8 in the culture supernatant were determined by ELISA.Results:  Anti‐HLA‐A2 serum increased the formation of aggregates between monocytes and HLA‐A2‐positive platelets, but not HLA‐A2‐negative platelets, in a dose‐dependent manner. Antiserum also increased the number of platelets bound to monocytes in a time‐dependent manner. The addition of anti‐P‐selectin glycoprotein ligand (PSGL‐1) mAb almost completely inhibited the formation of platelet–monocyte aggregates as well as the number of platelets bound to monocytes. When HLA‐A2‐positive or HLA‐A2‐negative platelets were incubated with HLA‐A2‐negative PBMNCs in the presence of anti‐HLA‐A2, the level of IL‐1β and IL‐8 in the supernatant of coculture was significantly higher in HLA‐A2‐positive platelets than in HLA‐A2‐negative platelets. The addition of anti‐PSGL‐1 mAb partially but significantly inhibited the production of both IL‐1β and IL‐8.Conclusions:  The activation of platelets with anti‐HLA Class I alloantibody caused the formation of platelet–monocyte aggregates, followed by the production of IL‐1β and IL‐8, in a cognate antigen–antibody manner. The adhesive interaction of P‐selectin and PSGL‐1 at least partially contributed to these phenomena.
Detection and Identification of Three ‘Candidatus Phytoplasma’ Species in Picea spp. Trees in Poland
Authors: Kamińska Maria , Berniak Hanna 
Published: September 2011

AbstractWe report the detection of phytoplasmas in Picea abies, Picea glauca and Picea pungens trees with witches’ brooms and other growth abnormalities and also in symptomless trees. Phytoplasmas were detected in c. 25% of the tested plants by polymerase chain reaction using phytoplasma universal P1/P7 followed by R16F2n/R16R2 primer pairs. The phytoplasmas were classified as members of the phylogenetic groups: 16SrI, ‘Ca. Phytoplasma asteris’; 16SrIII, X‐disease phytoplasma group; and 16SrXXI, ‘Ca. Phytoplasma pini’.
Long‐term outcomes of living kidney donors: A single centre experience of 29 years
Authors: CHU KWOK‐HONG , POON CLARA KA‐YAN , LAM CHUNG‐MAN , CHEUK AU , YIM KA‐FAI , LEE WILLIAM , TANG HON‐LOK , CHAN HILDA WAI‐HAN , FUNG KA‐SHUN , TONG KWOK‐LUNG 
Published: September 2011

ABSTRACTAim:  Living kidney donation provides the best source of kidney graft. The mortality and morbidity rates are small but the long‐term effects have not been studied. This is a report on our 29‐year experience of living kidney donation.Methods:  All living donors were arranged to have follow‐ups. Defaulters were traced via a territory‐wide computer system.Results:  A total of 149 living kidney donor operations were performed. 136/149 records were available. 41 defaulted follow‐up. One donor died of multiple myeloma. The male to female ratio was 1.00 to 1.52. Mean age at donation was 33.94 ± 9.66 years. Mean follow‐up duration was 160.39 ± 87.96 months. Hypertension was diagnosed in 27 donors (19.9%). 22 donors (17.3%) had stage 3 chronic kidney disease (CKD). Glomerular filtration rate (GFR) dropped from 90.95 ± 15.62 mL/min per 1.73 m2 at time 0 to 66.29 ± 12.06 mL/min per 1.73 m2 at 2 years. GFR improved subsequently and remained stable for 25 years. Age at donation was associated with hypertension (HT) in univariate and multivariate analyses. HT was not associated with sex or GFRs over time. Using binary logistic regression, age at donation was associated with the development of stage 3 CKD and GFR before donation was associated with lower CKD risk. In multivariate analysis, only age at donation was associated with CKD. Other co‐morbidities included: hyperlipidaemia 16/136, diabetes mellitus 6/136, cardiovascular event 1/136, stroke 1/136 and cancer 5/136.Conclusions:  Living kidney donors had reductions in GFR post uninephrectomy with subsequent improvement. A significant proportion developed HT and stage 3 CKD. Age at donation was a strong determinant of development of HT and stage 3 CKD.
CAPSULE ENDOSCOPY FINDINGS IN PATIENTS WITH OCCULT OR OVERT BLEEDING OLDER THAN 80 YEARS
Authors: TSIBOURIS PANAGIOTIS , KALANTZIS CHRISSOSTOMOS , APOSTOLOPOULOS PERIKLIS , ALEXANDRAKIS GEORGIOS , MAVROGIANNI PANAGIOTA , KALANTZIS NIKOLAOS 
Published: September 2011

Background:  Overt and occult bleeding are the main indications for a wireless capsule endoscopy (WCE) study of the small bowel. Most published studies omit patients aged over 80.Aim:  To determine whether WCE is feasible in patients with overt or occult bleeding over age 80 and to define the spectrum of small bowel pathologies in this age group.Patients and Methods:  In a retrospective non‐randomized tertiary care study, 60 patients at least 80 years or older (aged group) and 120 matched patients aged <80 years (younger group) with overt or occult bleeding (including iron deficiency anaemia) and no significant gastroscopic or colonoscopic findings underwent WCE.Results:  Of the 180 patients, 46 (77%) patients in the aged group and 97 (81%) in the younger group successfully completed small bowel study (P = 0.51). There was no difference in gastric transit time and small bowel passing time between the two groups. More patients in the aged group (48 cases, 80%) than the younger group (56 cases, 47%) presented with small bowel angiodysplasias (P < 0.0001). Nevertheless, there was no difference between the two groups concerning ulcerative and neoplastic lesions. No patient presented with capsule impaction, but more patients in the aged group (35 cases, 58%) than in the younger group (10 cases, 8%) found the study difficult and tiresome (P < 0.001). Preparation validation was poor in 34% of small bowel lumen in the aged group and 19% in the younger group (P = 0.03).Conclusion:  WCE is feasible, although rather tiresome, in patients over the age of 80. Though the vast majority of patients older than 80 presented with angiodysplasias, there were no differences between the aged and younger groups in the presence of ulcerative lesions and polyps or tumors.
Local anesthetics and their adjuncts
Authors: Mazoit Jean‐Xavier 
Published: September 2011

SummaryLocal anesthetics (LA) block propagation of impulses along nerve fibers by inactivation of voltage‐gated sodium channels, which initiate action potentials (1). They act on the cytosolic side of phospholipid membranes. Two main chemical compounds are used, amino esters and amino amides. Amino esters are degraded by pseudocholinesterases in plasma. Amino amides are metabolized exclusively by the liver. Only amide LAs will be considered in this article.
A novel platelet‐activating factor acetylhydrolase discovered in a metagenome from the earthworm‐associated microbial community
Authors: Navarro‐Fernández José , Nechitaylo Taras Y. , Guerrero José A. , Golyshina Olga V. , García‐Carmona Francisco , Sánchez‐Ferrer Álvaro , Golyshin Peter N. 
Published: September 2011

SummaryMetagenomics is an emerging field for mining the bioresources for new biomolecules for potential application in biotechnology and biomedicine. In the present study, a novel acetylhydrolase (Est13) was detected during the function‐based screening of a metagenomic library established from the DNA extracted from the cellulose‐depleting microbial community set up with an earthworm cast. Analysis showed that Est13 exhibited some similarities with a human and parasite platelet‐activating factor acetylhydrolase (PAF‐AH) belonging to the SGNH hydrolase superfamily. Biochemical characterization of the purified recombinant enzyme using substrates common for hydrolases of this superfamily demonstrated that Est13 hydrolysed p‐nitrophenyl acetate quite efficiently, with a kcat/KM value of 3209 mM−1 s−1. The Est13 showed highest activity at pH 8.0 and 40°C, conditions in which it is relatively stable compared with known PAF‐AHs. In vitro functional analysis of the platelet‐activating factor hydrolysis showed a dose‐ and time‐dependent inhibition of platelet aggregation in the range of 2–4 µM, making this enzyme a potential candidate for biomedical applications.
The impact of the two‐week wait referral pathway on rectal cancer survival
Authors: Currie A. C. , Evans J. , Smith N. J. , Brown G. , Abulafi A. M. , Swift R. I. 
Published: September 2011

AbstractAim  The aim of this study was to compare the outcome of patients with rectal cancer referred through the two‐week wait (TWW) system with those identified by routine referral pathways (non‐TWW).Method  A prospective study was carried out of 125 consecutive patients diagnosed with rectal cancer between January 2000 and December 2005 (6 years) in one district general hospital. Data were recorded prospectively in a local clinicopathological registry. The patients were divided into two groups: group 1 (TWW) and group 2 (routine referral pathway).Results  Fifty‐two (41%) of the 125 patients were diagnosed through the TWW (group 1). There was no significant difference in patient demographics, including baseline tumour characteristics, between the two groups. There was no difference in preoperative or postoperative T stage between the two groups (P = 0.63). There was no significant difference in circumferential margin positivity (five of 52 in group 1 vs four of 73 in group 2; P = 0.52) or local recurrence rates (P = 0.37). The 5‐year all‐cause mortality was 49% for group 1 and 52% for group 2 (P = 0.3). The overall disease‐free survival was similar in the two groups (1521 days for group 1 vs 1591 days for group 1, P = 0.29).Conclusion  Referral under the TWW strategy does not translate into improved survival in rectal cancer.
Onchocerca lupicausing ocular disease in two cats
Authors: Labelle Amber L. , Daniels Joshua B. , Dix Michael , Labelle Philippe 
Published: September 2011

AbstractAlthough canine ocular onchocerciasis has been well described as an emerging pathogen of dogs in Europe and North America over the past 20 years, there are no previous reports of feline ocular onchocerciasis. This report details the clinical, histopathologic, and molecular diagnosis of two domestic short hair cats residing in the United States infected withOnchocerca lupicausing episcleritis and orbital cellulitis. The results of this report suggest thatO. lupiis a newly recognized disease of domestic cats.
The effect of dorzolamide 2% on circadian intraocular pressure in cats with primary congenital glaucoma
Authors: Sigle Kelly J. , Camaño‐Garcia Gabriel , Carriquiry Alicia L. , Betts Daniel M. , Kuehn Markus H. , McLellan Gillian J. 
Published: September 2011

AbstractObjective To determine the extent of fluctuation in circadian intraocular pressure (IOP) and the efficacy of topical dorzolamide 2% q 8 h in lowering IOP and blunting circadian fluctuation in IOP in glaucomatous cats.Animals studied Seven adult cats with primary congenital glaucoma (PCG).Procedures Measurements of IOP and pupil diameter were obtained for both eyes (OU) of each cat q 4 h for 12 days. Cats were housed in a laboratory animal facility with a 12‐h light:dark cycle. Baseline values were established for 2 days. For the next 5 days, placebo (1.4% polyvinyl alcohol) was administered OU q 8 h. Dorzolamide 2% was then administered OU q 8 h for a further 5 days. A multivariate mixed linear model was fitted to the data, with parameters estimated from a Bayesian perspective. The 4 amtime point was selected as the reference for the purposes of comparisons.Results Estimated mean IOP for the reference time point pre‐treatment was symmetric (about 33 mmHg OU). In all cats, IOP was significantly lower during the diurnal phase, relative to the 4 ammeasurements, with highest IOP observed 2–6 h after the onset of the dark phase. Circadian fluctuations in IOP were dampened during the treatment period. There was a significant decrease in IOP in all cats during the dorzolamide treatment period (estimated mean for the treatment period reference = 17.9 mmHg OU).Conclusions Topical dorzolamide 2% q 8 h is effective in reducing IOP and IOP fluctuation in cats with PCG.
Brief interventions are effective in reducing alcohol consumption in opiate‐dependent methadone‐maintained patients: Results from an implementation study
Authors: DARKER CATHERINE D. , SWEENEY BRION P. , EL HASSAN HAYTHAM O. , SMYTH BOBBY P. , IVERS JO‐HANNA H. , BARRY JOE M. 
Published: September 2011

AbstractIntroduction and Aims. An implementation study to test the feasibility and effectiveness of brief interventions (BIs) to reduce hazardous and harmful alcohol consumption in opiate‐dependent methadone‐maintained patients.Design and Methods. Before and after intervention comparison of Alcohol Use Disorders Identification Test (AUDIT‐C) scores from baseline to 3 month follow up. Seven hundred and ten (82%) of the 863 eligible methadone‐maintained patients within three urban addiction treatment clinics were screened. A World Health Organization protocol for a clinician‐delivered single BI to reduce alcohol consumption was delivered. The full AUDIT questionnaire was used at baseline (T1) to measure alcohol consumption and related harms; and in part as a screening tool to exclude those who may be alcohol‐dependent. AUDIT‐C was used at 3 month follow up (T2) to assess any changes in alcohol consumption.Results. One hundred and sixty (23% of overall sample screened) ‘AUDIT‐positive’ cases were identified at baseline screening with a mean total full AUDIT score of 13.5 (SD 6.7). There was a statistically significant reduction in AUDIT‐C scores from T1 (
, SD = 2.35) to T2 (, SD = 2.66) for the BI group (z = −3.98, P < 0.01). There was a statistically significant decrease in the proportion of men who were AUDIT‐positive from T1 to T2 (χ2 = 8.25, P < 0.003).Discussion and Conclusions. It is feasible for a range of clinicians to screen for problem alcohol use and deliver BI within community methadone clinics. Opiate‐dependent patients significantly reduced their alcohol consumption as a result of receiving a BI. [Darker CD, Sweeney BP, El Hassan HO, Smyth BP, Ivers J‐HH, Barry JM. Brief interventions are effective in reducing alcohol consumption in opiate‐dependent methadone‐maintained patients: Results from an implementation study. Drug Alcohol Rev 2012;31:348–356]
The Effects of Culture and Structure on Strategic Flexibility during Business Model Innovation
Authors: Bock Adam J. , Opsahl Tore , George Gerard , Gann David M. 
Published: September 2011

abstractThis study uses responses from 107 multinational firms to reveal CEO perceptions of the drivers of strategic flexibility during business model innovation. While the positive effect of creative culture is confirmed, partner reliance reduces strategic flexibility during business model innovation. Further, structural change is disaggregated into efforts that either focus managerial attention on core activities or reconfigure existing activities. CEOs perceive that structural flexibility requires structural simplification while retaining control of non‐core functions. We find that the relative magnitude of business model innovation effort moderates the effect of reconfiguration on strategic flexibility. The implications for theories of organizational design and dynamic capabilities are discussed.