bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cerebral hyperperfusion syndrome post‐carotid artery stenting
Authors: Tan GS‐S , Phatouros CC 
Published: April 2009

SummaryCerebral hyperperfusion syndrome is increasingly recognized as a complication in carotid artery stenting for severe internal carotid artery stenosis. This study reviews the cases of hyperperfusion syndrome occurring after this procedure. We reviewed our database of 170 cases of internal carotid artery stenting carried out at our hospital between January 1999 and June 2006. A radiology search was also carried out to identify those who had CT or MRI within 1 month of post‐carotid artery stenting. We had four patients who developed cerebral hyperperfusion syndrome. One patient developed cerebral oedema, one patient had petechial intracerebral haemorrhage and two patients had large intracerebral haemorrhages, one of whom died. This gives a risk of 2.3% (95% confidence interval 2.27–2.323). All patients with cerebral haemorrhage presented within 6 h. Both patients with large intracerebral haemorrhage had carotid stenting within 3 weeks after presentation of symptoms and all had critically severe stenosis of 95% or more. In our series, large intracerebral haemorrhage has occurred only in patients who have been treated early. Cerebral hyperperfusion is an uncommon but serious complication post‐carotid stenting. Further studies comparing early treatment of endarterectomy and carotid stenting are awaited.
Comprehensive Australasian multicentre dosimetric intercomparison: Issues, logistics and recommendations
Authors: Ebert MA , Harrison KM , Cornes D , Howlett SJ , Joseph DJ , Kron T , Hamilton CS , Denham JW 
Published: April 2009

SummaryThe present paper describes the logistics of the 2004–2008 Australasian Level III Dosimetry Intercomparison. Dosimetric intercomparisons (or ‘audits’) can be used in radiotherapy to evaluate the accuracy and quality of radiation delivery. An intercomparison was undertaken in New Zealand and Australia to evaluate the feasibility and logistics of ongoing dosimetric intercomparisons that evaluate all steps in the radiotherapy treatment process, known as a ‘Level III’ intercomparison. The study commenced in 2002 with the establishment of a study team, definition of the study protocol, acquisition of appropriate equipment and recruitment of participating radiotherapy centres. Measurements were undertaken between October 2004 and March 2008, and included collation of data on time, costs and logistics of the study. Forty independent Australian and New Zealand radiotherapy centres agreed to participate. Measurement visits were made to 37 of these centres. Data is presented on the costs of the study and the level of support required. The study involved the participation of 16 staff at the study centre who invested over 4000 hours in the study, and of over 200 professionals at participating centres. Recommendations are provided for future phantom‐based intercomparisons. It is hoped that the present paper will be of benefit to any centres or groups contemplating similar activities by identifying the processes involved in establishing the study, the potential hazards and pitfalls, and expected resource requirements.
Macular function after intravitreal triamcinolone acetonide injection for diabetic macular oedema
Authors: Karacorlu Murat , Ozdemir Hakan , Senturk Fevzi , Karacorlu Serra Arf , Uysal Omer 
Published: April 2009

Abstract.Purpose:  We aimed to evaluate the effect of intravitreal triamcinolone acetonide (IVTA) on macular function in patients with diabetic macular oedema (DMO).Methods:  Eleven eyes in 11 patients with DMO were enrolled. In each eye, at baseline and at 30 days after IVTA injection, logMAR visual acuity (VA), macular sensitivity, fixation stability and fixation location by MP‐1 microperimetry and optical coherence tomography (OCT) foveal thickness were assessed.Results:  Thirty days after IVTA injection, eyes with DMO showed a significant (p < 0.001) reduction in foveal thickness and significant (p < 0.01) increases in logMAR VA and MP‐1 retinal sensitivity (p < 0.001). There was also significant (p = 0.046) improvement in fixation location and some improvement in fixation stability, although the latter was not significant (p = 0.08).Conclusions:  In eyes with DMO, short‐term improvement in retinal sensitivity and fixation properties can be achieved by IVTA injection.
Reducing the incidence of early postoperative vitreous haemorrhage by preoperative intravitreal bevacizumab in vitrectomy for diabetic tractional retinal detachment
Authors: Yeung Ling , Liu Laura , Wu Wei‐Chi , Kuo Ya‐Hui , Chao An‐Ning , Chen Kuan‐Jen , Yang Ko‐Jen , Chen Tun‐Lu , Lai Chi‐Chun 
Published: April 2009

Acta Ophthalmol. 2010: 88: 635–640Abstract.Purpose:  This study aimed to evaluate whether preoperative intravitreal injection of bevacizumab reduces early postoperative vitreous haemorrhage (VH) in vitrectomy for diabetic tractional retinal detachment.Methods:  We conducted a retrospective chart review of a consecutive, interventional case series. This included 29 eyes (27 patients) in the bevacizumab group and 40 eyes (37 patients) in the non‐bevacizumab group. For statistical analysis, each patient was assigned to one of four groups according to the haemostatic modalities used (group 1, none; group 2, only long‐acting gas; group 3, only preoperative intravitreal bevacizumab; group 4, both long‐acting gas and preoperative intravitreal bevacizumab). The primary outcome measure was the incidence of early postoperative VH. The secondary outcome measure was visual acuity (VA) at 1 month.Results:  The incidence of early postoperative VH was highest in group 1 (63%), followed by group 2 (21%), group 3 (20%) and group 4 (5%). Group 3 showed the best visual recovery in the first month. All eyes in group 3 reached VA ≥ 1/100 at 1 month after the operation, compared with 44%, 29% and 42% in groups 1, 2 and 4, respectively.Conclusions:  Preoperative intravitreal injection of bevacizumab may be useful for reducing early postoperative VH in vitrectomy for diabetic tractional retinal detachment. Eyes receiving preoperative intravitreal bevacizumab without the use of long‐acting gas achieved the best visual recovery at 1 month after the operation.
Combined intravitreal bevacizumab and triamcinolone in exudative age‐related macular degeneration
Authors: Jonas Jost B. , Libondi Teodosio , Golubkina Lidia , Spandau Ulrich H. , Schlichtenbrede Frank , Rensch Florian 
Published: April 2009

Acta Ophthalmol. 2010: 88: 630–634Abstract.Purpose:  We report on the combined application of intravitreal bevacizumab and triamcinolone acetonide for treatment of exudative age‐related macular degeneration (AMD).Methods:  The clinical interventional case‐series study included 16 patients (16 eyes) with exudative AMD who had previously received 3.5 ± 1.8 mono‐injections of bevacizumab (1.5 mg) without significant improvement in visual acuity (VA) or reduction in macular exudation. All patients underwent a combined intravitreal injection of bevacizumab (1.5 mg) and triamcinolone acetonide (about 20 mg). Main outcome measures were VA and macular thickness as determined by optical coherence tomography. All patients were re‐examined at 2–3 months after the intervention.Results:  Visual acuity improved significantly (p = 0.03) from 0.80 ± 0.40 logMAR prior to the combined injection to 0.65 ± 0.42 logMAR at 3 months after the injection. An improvement of ≥ 1 Snellen line was found in eight subjects, an increase of ≥ 2 lines in five subjects, and an improvement of ≥ 3 lines in two subjects. One patient lost 1 line and one patient lost 3 lines. Central retinal thickness decreased significantly from 272 ± 62 μm to 220 ± 47 μm (p = 0.03). At the 6‐month follow‐up examination, central retinal thickness had increased again to 319 ± 142 μm, which was not significantly (p = 0.30) different from baseline measurements.Conclusions:  The combined intravitreal application of bevacizumab and triamcinolone may temporarily be helpful in the treatment of exudative AMD if previous intravitreal bevacizumab mono‐injections have failed to improve vision and reduce macular oedema.
Requirement of Polyphosphate by
Pseudomonas fluorescens
Pf0-1 for Competitive Fitness and Heat Tolerance in Laboratory Media and Sterile Soil
Authors: Silby Mark W. , Nicoll Julie S. , Levy Stuart B. 
Published: April 2009

ABSTRACT

Knowledge of the genetic basis for bacterial survival and persistence in soil is a critical component in the development of successful biological control strategies and for understanding the ecological success of bacteria. We found a locus specifying polyphosphate kinase (
ppk
) and a nonpredicted antisense RNA (
iiv8
) in
Pseudomonas fluorescens
Pf0-1 to be necessary for optimal competitive fitness in LB broth culture and sterile loam soil. Pf0-1 lacking
ppk
and
iiv8
was more than 10-fold less competitive against wild-type Pf0-1 in sterile loam soil low in inorganic phosphate. Studies indicated that
ppk
, and not
iiv8
, was required for competitive fitness. No role for
iiv8
was identified. While a
ppk
and
iiv8
mutant of Pf0-1 did not have increased sensitivity to osmotic, oxidative, and acid stress, it was more sensitive to elevated temperatures in laboratory medium and during growth in sterile soil.
ppk
was shown to be part of the Pho regulon in
P. fluorescens
, being upregulated in response to a low external P
i
concentration. Of importance, overproduction of polyphosphate in the soil environment appears to be more deleterious than production of none at all. Our findings reveal a new role for polyphosphate (and the need for proper regulation of its production) in competitive fitness of
P. fluorescens
in laboratory and soil environments.
Assessment of the Diversity, Abundance, and Ecological Distribution of Members of Candidate Division SR1 Reveals a High Level of Phylogenetic Diversity but Limited Morphotypic Diversity
Authors: Davis James P. , Youssef Noha H. , Elshahed Mostafa S. 
Published: April 2009

ABSTRACT
We used a combination of 16S rRNA gene clone library surveys, quantitative PCR (qPCR) analysis, and fluorescent in situ hybridization to investigate the diversity, abundance, and distribution of members of candidate division SR1 in multiple habitats. Using SR1-specific 16S rRNA gene primers, we identified multiple novel SR1 lineages in four different anaerobic environments: sediments from Zodletone Spring, a sulfide- and sulfur-rich spring in southwestern Oklahoma; inner layers of microbial mats obtained from Sperm Pool, a high-temperature, low-pH pool (55°C, pH 2.5) in Yellowstone National Park; fresh bovine ruminal contents; and anaerobic freshwater pond sediments (Duck Pond) in Norman, Oklahoma. qPCR analysis indicated that SR1 members constitute a small fraction (<0.01%) of the microbial communities in Duck Pond and ruminal samples but constitute a significant fraction (11.6 and 48.7%) of the total number of bacterial 16S rRNA genes in Zodletone Spring and the inner layers of Sperm Pool microbial mat samples, respectively. By using SR1-specific fluorescent probes, filamentous cells were identified as the sole SR1 morphotype in all environments examined, with the exception of Sperm Pool, where a second bacillus morphotype was also identified. Using a full-cycle 16S rRNA approach, we show that each of these two morphotypes corresponds to a specific phylogenetic lineage identified in the Sperm Pool clone library. This work greatly expands the intralineage phylogenetic diversity within candidate division SR1 and provides valuable quantification and visualization tools that could be used for investigating the ecological roles, dynamics, and genomics of this as-yet-uncultured bacterial phylum.
Archaeal Diversity and the Prevalence of
Crenarchaeota
in Salt Marsh Sediments
Authors: Nelson Katelyn A. , Moin Nicole S. , Bernhard Anne E. 
Published: April 2009

ABSTRACT

Crenarchaeal 16S rRNA sequences constituted over 70% of the archaeal clones recovered from three salt marsh sites dominated by different grasses. Group I.1a
Crenarchaeota
dominated at two sites, while group I.3b
Crenarchaeota
sequences were most abundant at a third site. Abundances of 16S rRNA genes related to “
Candidatus
Nitrosopumilus maritimus” differed by site and sampling date.
Utilization of Mucus from the Coral
Acropora palmata
by the Pathogen
Serratia marcescens
and by Environmental and Coral Commensal Bacteria
Authors: Krediet Cory J. , Ritchie Kim B. , Cohen Matthew , Lipp Erin K. , Sutherland Kathryn Patterson , Teplitski Max 
Published: April 2009

ABSTRACT

In recent years, diseases of corals caused by opportunistic pathogens have become widespread. How opportunistic pathogens establish on coral surfaces, interact with native microbiota, and cause disease is not yet clear. This study compared the utilization of coral mucus by coral-associated commensal bacteria (“
Photobacterium mandapamensis
” and
Halomonas meridiana
) and by opportunistic
Serratia marcescens
pathogens.
S. marcescens
PDL100 (a pathogen associated with white pox disease of
Acroporid
corals) grew to higher population densities on components of mucus from the host coral. In an in vitro coculture on mucus from
Acropora palmata
,
S. marcescens
PDL100 isolates outgrew coral isolates. The white pox pathogen did not differ from other bacteria in growth on mucus from a nonhost coral,
Montastraea faveolata.
The ability of
S. marcescens
to cause disease in acroporid corals may be due, at least in part, to the ability of strain PDL100 to build to higher population numbers within the mucus surface layer of its acroporid host. During growth on mucus from
A. palmata
, similar glycosidase activities were present in coral commensal bacteria, in
S. marcescens
PDL100, and in environmental and human isolates of
S. marcescens
. The temporal regulation of these activities during growth on mucus, however, was distinct in the isolates. During early stages of growth on mucus, enzymatic activities in
S. marcescens
PDL100 were most similar to those in coral commensals. After overnight incubation on mucus, enzymatic activities in a white pox pathogen were most similar to those in pathogenic
Serratia
strains isolated from human mucosal surfaces.
Diversity and Abundance of Ammonia-Oxidizing Archaea in Hydrothermal Vent Chimneys of the Juan de Fuca Ridge
Authors: Wang Shufang , Xiao Xiang , Jiang Lijing , Peng Xiaotong , Zhou Huaiyang , Meng Jun , Wang Fengping 
Published: April 2009

ABSTRACT

The abundance and diversity of archaeal ammonia monooxygenase subunit A (
amoA
) genes from hydrothermal vent chimneys at the Juan de Fuca Ridge were investigated. The majority of the retrieved archaeal
amoA
sequences exhibited identities of less than 95% to those in the GenBank database. Novel ammonia-oxidizing archaea may exist in the hydrothermal vent environments.
Identification of Promoters for Efficient Gene Expression inMagnetospirillum gryphiswaldense
Authors: Lang Claus , Pollithy Anna , Schüler Dirk 
Published: April 2009

ABSTRACTTo develop an expression system for the magnetotactic bacteriumMagnetospirillum gryphiswaldense, we compared gene expression from the widely usedEscherichia coliPlacpromoter with that from known and predicted genuineM. gryphiswaldensepromoters. With the use of green fluorescent protein as a reporter, the highest expression level was observed with the magnetosomal PmamDCpromoter. We demonstrate that this promoter can be used for the expression of modified magnetosome proteins to generate “antibody-binding” magnetosomes.
An IcmF Family Protein, ImpL
M
, Is an Integral Inner Membrane Protein Interacting with ImpK
L
, and Its Walker A Motif Is Required for Type VI Secretion System-Mediated Hcp Secretion in
Agrobacterium tumefaciens
Authors: Ma Lay-Sun , Lin Jer-Sheng , Lai Erh-Min 
Published: April 2009

ABSTRACT

An intracellular multiplication F (IcmF) family protein is a conserved component of a newly identified type VI secretion system (T6SS) encoded in many animal and plant-associated
Proteobacteria
. We have previously identified ImpL
M
, an IcmF family protein that is required for the secretion of the T6SS substrate hemolysin-coregulated protein (Hcp) from the plant-pathogenic bacterium
Agrobacterium tumefaciens
. In this study, we characterized the topology of ImpL
M
and the importance of its nucleotide-binding Walker A motif involved in Hcp secretion from
A. tumefaciens
. A combination of β-lactamase-green fluorescent protein fusion and biochemical fractionation analyses revealed that ImpL
M
is an integral polytopic inner membrane protein comprising three transmembrane domains bordered by an N-terminal domain facing the cytoplasm and a C-terminal domain exposed to the periplasm.

impL
M

mutants with substitutions or deletions in the Walker A motif failed to complement the

impL
M

deletion mutant for Hcp secretion, which provided evidence that ImpL
M
may bind and/or hydrolyze nucleoside triphosphates to mediate T6SS machine assembly and/or substrate secretion. Protein-protein interaction and protein stability analyses indicated that there is a physical interaction between ImpL
M
and another essential T6SS component, ImpK
L
. Topology and biochemical fractionation analyses suggested that ImpK
L
is an integral bitopic inner membrane protein with an N-terminal domain facing the cytoplasm and a C-terminal OmpA-like domain exposed to the periplasm. Further comprehensive yeast two-hybrid assays dissecting ImpL
M
-ImpK
L
interaction domains suggested that ImpL
M
interacts with ImpK
L
via the N-terminal cytoplasmic domains of the proteins. In conclusion, ImpL
M
interacts with ImpK
L
, and its Walker A motif is required for its function in mediation of Hcp secretion from
A. tumefaciens
.
A Novel Allele of
kaiA
Shortens the Circadian Period and Strengthens Interaction of Oscillator Components in the Cyanobacterium
Synechococcus elongatus
PCC 7942
Authors: Chen You , Kim Yong-Ick , Mackey Shannon R. , Holtman C. Kay , LiWang Andy , Golden Susan S. 
Published: April 2009

ABSTRACT

The basic circadian oscillator of the unicellular fresh water cyanobacterium
Synechococcus elongatus
PCC 7942, the model organism for cyanobacterial circadian clocks, consists of only three protein components: KaiA, KaiB, and KaiC. These proteins, all of which are homomultimers, periodically interact to form large protein complexes with stoichiometries that depend on the phosphorylation state of KaiC. KaiA stimulates KaiC autophosphorylation through direct physical interactions. Screening a library of
S. elongatus
transposon mutants for circadian clock phenotypes uncovered an atypical short-period mutant that carries a
kaiA
insertion. Genetic and biochemical analyses showed that the short-period phenotype is caused by the truncation of KaiA by three amino acid residues at its C terminus. The disruption of a negative element upstream of the
kaiBC
promoter was another consequence of the insertion of the transposon; when not associated with a truncated
kaiA
allele, this mutation extended the circadian period. The circadian rhythm of KaiC phosphorylation was conserved in these mutants, but with some modifications in the rhythmic pattern of KaiC phosphorylation, such as the ratio of phosphorylated to unphosphorylated KaiC and the relative phase of the circadian phosphorylation peak. The results showed that there is no correlation between the phasing of the KaiC phosphorylation pattern and the rhythm of gene expression, measured as bioluminescence from luciferase reporter genes. The interaction between KaiC and the truncated KaiA was stronger than normal, as shown by fluorescence anisotropy analysis. Our data suggest that the KaiA-KaiC interaction and the circadian pattern of KaiC autophosphorylation are both important for determining the period, but not the relative phasing, of circadian rhythms in
S. elongatus
.
Role of Quorum Sensing in
Sinorhizobium meliloti
-Alfalfa Symbiosis
Authors: Gurich Nataliya , González Juan E. 
Published: April 2009

ABSTRACT

The ExpR/Sin quorum-sensing system of the gram-negative soil bacterium
Sinorhizobium meliloti
plays an important role in the establishment of symbiosis with its host plant
Medicago sativa
. A mutant unable to produce autoinducer signal molecules (
sinI
) is deficient in its ability to invade the host, but paradoxically, a strain lacking the quorum-sensing transcriptional regulator ExpR is as efficient as the wild type. We compared the whole-genome expression profile of the wild-type strain with strains missing one of the quorum-sensing regulatory components to identify genes controlled by the ExpR/Sin system throughout the different phases of the bacterial growth cycle, as well as in planta. Our analyses revealed that ExpR is a highly versatile regulator with a unique ability to show different regulatory capabilities in the presence or absence of an autoinducer. In addition, this study provided us with insight into the plant invasion defect displayed by the autoinducer mutant. We also discovered that the ExpR/Sin quorum-sensing system is repressed after plant invasion. Therefore, quorum sensing plays a crucial role in the regulation of many cell functions that ensures the successful invasion of the host and is inactivated once symbiosis is established.
6-Pyruvoyltetrahydropterin Synthase Paralogs Replace the Folate Synthesis Enzyme Dihydroneopterin Aldolase in Diverse Bacteria
Authors: Pribat Anne , Jeanguenin Linda , Lara-Núñez Aurora , Ziemak Michael J. , Hyde John E. , de Crécy-Lagard Valérie , Hanson Andrew D. 
Published: April 2009

ABSTRACT

Dihydroneopterin aldolase (FolB) catalyzes conversion of dihydroneopterin to 6-hydroxymethyldihydropterin (HMDHP) in the classical folate biosynthesis pathway. However,
folB
genes are missing from the genomes of certain bacteria from the phyla
Chloroflexi
,
Acidobacteria
,
Firmicutes
,
Planctomycetes
, and
Spirochaetes
. Almost all of these
folB
-deficient genomes contain an unusual paralog of the tetrahydrobiopterin synthesis enzyme 6-pyruvoyltetrahydropterin synthase (PTPS) in which a glutamate residue replaces or accompanies the catalytic cysteine. A similar PTPS paralog from the malaria parasite
Plasmodium falciparum
is known to form HMDHP from dihydroneopterin triphosphate in vitro and has been proposed to provide a bypass to the FolB step in vivo. Bacterial genes encoding PTPS-like proteins with active-site glutamate, cysteine, or both residues were accordingly tested together with the
P. falciparum
gene for complementation of the
Escherichia coli folB
mutation. The
P. falciparum
sequence and bacterial sequences with glutamate or glutamate plus cysteine were active; those with cysteine alone were not. These results demonstrate that PTPS paralogs with an active-site glutamate (designated PTPS-III proteins) can functionally replace FolB in vivo. Recombinant bacterial PTPS-III proteins, like the
P. falciparum
enzyme, mediated conversion of dihydroneopterin triphosphate to HMDHP, but other PTPS proteins did not. Neither PTPS-III nor other PTPS proteins exhibited significant dihydroneopterin aldolase activity. Phylogenetic analysis indicated that PTPS-III proteins may have arisen independently in various PTPS lineages. Consistent with this possibility, merely introducing a glutamate residue into the active site of a PTPS protein conferred incipient activity in the growth complementation assay, and replacing glutamate with alanine in a PTPS-III protein abolished complementation.
Characterization of theCorynebacterium glutamicumΔpimB′ ΔmgtADouble Deletion Mutant and the Role ofMycobacterium tuberculosisOrthologues Rv2188c and Rv0557 in Glycolipid Biosynthesis
Authors: Mishra Arun K. , Batt Sarah , Krumbach Karin , Eggeling Lothar , Besra Gurdyal S. 
Published: April 2009

ABSTRACTIn this study, utilizing aCorynebacterium glutamicumΔpimB′ ΔmgtAdouble deletion mutant, we unequivocally assign the in vivo functions of Rv2188c as an Ac1PIM1:mannosyltransferase (originally termed PimB′Mt[Mycobacterium tuberculosisPimB′]) and Rv0557 as a GlcAGroAc2:mannosyltransferase (originally termed PimBMt), which we have reassigned as PimBMtand MgtAMt, respectively, inMycobacterium tuberculosis.