bluuebunny/crossref_metadata_2025_split huggingface dataset:
Defects in leaf carbohydrate metabolism compromise acclimation to high light and lead to a high chlorophyll fluorescence phenotype in Arabidopsis thaliana
Authors: Schmitz Jessica , Schöttler Mark Aurel , Krueger Stephan , Geimer Stefan , Schneider Anja , Kleine Tatjana , Leister Dario , Bell Kirsten , Flügge Ulf-Ingo , Häusler Rainer E 
Published: January 2012

Abstract

Background
We have studied the impact of carbohydrate-starvation on the acclimation response to high light using Arabidopsis thaliana double mutants strongly impaired in the day- and night path of photoassimilate export from the chloroplast. A complete knock-out mutant of the triose phosphate/phosphate translocator (TPT; tpt-2 mutant) was crossed to mutants defective in (i) starch biosynthesis (adg1-1, pgm1 and pgi1-1; knock-outs of ADP-glucose pyrophosphorylase, plastidial phosphoglucomutase and phosphoglucose isomerase) or (ii) starch mobilization (sex1-3, knock-out of glucan water dikinase) as well as in (iii) maltose export from the chloroplast (mex1-2).

Results
All double mutants were viable and indistinguishable from the wild type when grown under low light conditions, but - except for sex1-3/tpt-2 - developed a high chlorophyll fluorescence (HCF) phenotype and growth retardation when grown in high light. Immunoblots of thylakoid proteins, Blue-Native gel electrophoresis and chlorophyll fluorescence emission analyses at 77 Kelvin with the adg1-1/tpt-2 double mutant revealed that HCF was linked to a specific decrease in plastome-encoded core proteins of both photosystems (with the exception of the PSII component cytochrome b559), whereas nuclear-encoded antennae (LHCs) accumulated normally, but were predominantly not attached to their photosystems. Uncoupled antennae are the major cause for HCF of dark-adapted plants. Feeding of sucrose or glucose to high light-grown adg1-1/tpt-2 plants rescued the HCF- and growth phenotypes. Elevated sugar levels induce the expression of the glucose-6-phosphate/phosphate translocator2 (GPT2), which in principle could compensate for the deficiency in the TPT. A triple mutant with an additional defect in GPT2 (adg1-1/tpt-2/gpt2-1) exhibited an identical rescue of the HCF- and growth phenotype in response to sugar feeding as the adg1-1/tpt-2 double mutant, indicating that this rescue is independent from the sugar-triggered induction of GPT2.

Conclusions
We propose that cytosolic carbohydrate availability modulates acclimation to high light in A. thaliana. It is conceivable that the strong relationship between the chloroplast and nucleus with respect to a co-ordinated expression of photosynthesis genes is modified in carbohydrate-starved plants. Hence carbohydrates may be considered as a novel component involved in chloroplast-to-nucleus retrograde signaling, an aspect that will be addressed in future studies.
TGF-β1 modulates the homeostasis between MMPs and MMP inhibitors through p38 MAPK and ERK1/2 in highly invasive breast cancer cells
Authors: Gomes Luciana R , Terra Letícia F , Wailemann Rosângela AM , Labriola Leticia , Sogayar Mari C 
Published: January 2012

Abstract

Background
Metastasis is the main factor responsible for death in breast cancer patients. Matrix metalloproteinases (MMPs) and their inhibitors, known as tissue inhibitors of MMPs (TIMPs), and the membrane-associated MMP inhibitor (RECK), are essential for the metastatic process. We have previously shown a positive correlation between MMPs and their inhibitors expression during breast cancer progression; however, the molecular mechanisms underlying this coordinate regulation remain unknown. In this report, we investigated whether TGF-β1 could be a common regulator for MMPs, TIMPs and RECK in human breast cancer cell models.

Methods
The mRNA expression levels of TGF-β isoforms and their receptors were analyzed by qRT-PCR in a panel of five human breast cancer cell lines displaying different degrees of invasiveness and metastatic potential. The highly invasive MDA-MB-231 cell line was treated with different concentrations of recombinant TGF-β1 and also with pharmacological inhibitors of p38 MAPK and ERK1/2. The migratory and invasive potential of these treated cells were examined in vitro by transwell assays.

Results
In general, TGF-β2, TβRI and TβRII are over-expressed in more aggressive cells, except for TβRI, which was also highly expressed in ZR-75-1 cells. In addition, TGF-β1-treated MDA-MB-231 cells presented significantly increased mRNA expression of MMP-2, MMP-9, MMP-14, TIMP-2 and RECK. TGF-β1 also increased TIMP-2, MMP-2 and MMP-9 protein levels but downregulated RECK expression. Furthermore, we analyzed the involvement of p38 MAPK and ERK1/2, representing two well established Smad-independent pathways, in the proposed mechanism. Inhibition of p38MAPK blocked TGF-β1-increased mRNA expression of all MMPs and MMP inhibitors analyzed, and prevented TGF-β1 upregulation of TIMP-2 and MMP-2 proteins. Moreover, ERK1/2 inhibition increased RECK and prevented the TGF-β1 induction of pro-MMP-9 and TIMP-2 proteins. TGF-β1-enhanced migration and invasion capacities were blocked by p38MAPK, ERK1/2 and MMP inhibitors.

Conclusion
Altogether, our results support that TGF-β1 modulates the mRNA and protein levels of MMPs (MMP-2 and MMP-9) as much as their inhibitors (TIMP-2 and RECK). Therefore, this cytokine plays a crucial role in breast cancer progression by modulating key elements of ECM homeostasis control. Thus, although the complexity of this signaling network, TGF-β1 still remains a promising target for breast cancer treatment.
Phylogenetic analysis of strains of Orf virus isolated from two outbreaks of the disease in sheep in Greece
Authors: Billinis Charalambos , Mavrogianni Vasia S , Spyrou Vasiliki , Fthenakis George C 
Published: January 2012

Abstract

Background
Although orf is endemic around the world, there are few descriptions of Orf virus strains and comparisons of these strains. We report the sequence and phylogenetic analysis of the partial B2L gene of Orf virus from two outbreaks of the disease in Greece. The first was an outbreak of genital form of the disease in a flock imported from France, whilst the second was an outbreak of the disease in the udder skin of ewes and around the mouth of lambs in an indigenous flock.

Results
Phylogenetic analysis was performed on a part (498 bp) of the B2L gene of 35 Parapoxvirus isolates, including the two Orf virus isolates recovered from each of the two outbreaks in the present study. This analysis revealed that the maximum nucleotide and amino-acid variation amongst Orf virus strains worldwide (n = 33) was 8.1% and 9.6%, respectively. The homology of the nucleotide and amino-acid sequences between the two Greek isolates was 99.0% and 98.8%, respectively. The two Greek isolates clustered only with Orf virus strains.

Conclusions
We suggest that there can be differences between strains based on their geographical origin. However, differences in the origin of strains or in the clinical presentation of the disease may not be associated with their pathogenicity. More work is required to determine if differing clinical presentations are linked to viral strain differences or if other factors, e.g., flock immunity, method of exposure or genetic susceptibility, are more important to determine the clinical presentation of the infection.
Biomechanical evaluation of predictive parameters of progression in adolescent isthmic spondylolisthesis: a computer modeling and simulation study
Authors: Sevrain Amandine , Aubin Carl-Eric , Gharbi Hicham , Wang Xiaoyu , Labelle Hubert 
Published: January 2012

Abstract

Background
Pelvic incidence, sacral slope and slip percentage have been shown to be important predicting factors for assessing the risk of progression of low- and high-grade spondylolisthesis. Biomechanical factors, which affect the stress distribution and the mechanisms involved in the vertebral slippage, may also influence the risk of progression, but they are still not well known. The objective was to biomechanically evaluate how geometric sacral parameters influence shear and normal stress at the lumbosacral junction in spondylolisthesis.

Methods
A finite element model of a low-grade L5-S1 spondylolisthesis was constructed, including the morphology of the spine, pelvis and rib cage based on measurements from biplanar radiographs of a patient. Variations provided on this model aimed to study the effects on low grade spondylolisthesis as well as reproduce high grade spondylolisthesis. Normal and shear stresses at the lumbosacral junction were analyzed under various pelvic incidences, sacral slopes and slip percentages. Their influence on progression risk was statistically analyzed using a one-way analysis of variance.

Results
Stresses were mainly concentrated on the growth plate of S1, on the intervertebral disc of L5-S1, and ahead the sacral dome for low grade spondylolisthesis. For high grade spondylolisthesis, more important compression and shear stresses were seen in the anterior part of the growth plate and disc as compared to the lateral and posterior areas. Stress magnitudes over this area increased with slip percentage, sacral slope and pelvic incidence. Strong correlations were found between pelvic incidence and the resulting compression and shear stresses in the growth plate and intervertebral disc at the L5-S1 junction.

Conclusions
Progression of the slippage is mostly affected by a movement and an increase of stresses at the lumbosacral junction in accordance with spino-pelvic parameters. The statistical results provide evidence that pelvic incidence is a predictive parameter to determine progression in isthmic spondylolisthesis.
Interim-treatment quantitative PET parameters predict progression and death among patients with hodgkin's disease
Authors: Tseng Diane , Rachakonda Leelanand P , Su Zheng , Advani Ranjana , Horning Sandra , Hoppe Richard T , Quon Andrew , Graves Edward E , Loo Billy W , Tran Phuoc T 
Published: January 2012

Abstract

Purpose
We hypothesized that quantitative PET parameters may have predictive value beyond that of traditional clinical factors such as the International Prognostic Score (IPS) among Hodgkin's disease (HD) patients.

Methods
Thirty HD patients treated at presentation or relapse had staging and interim-treatment PET-CT scans. The majority of patients (53%) had stage III-IV disease and 67% had IPS ≥ 2. Interim-treatment scans were performed at a median of 55 days from the staging PET-CT. Chemotherapy regimens used: Stanford V (67%), ABVD (17%), VAMP (10%), or BEACOPP (7%). Hypermetabolic tumor regions were segmented semiautomatically and the metabolic tumor volume (MTV), mean standardized uptake value (SUVmean), maximum SUV (SUVmax) and integrated SUV (iSUV) were recorded. We analyzed whether IPS, absolute value PET parameters or the calculated ratio of interim- to pre-treatment PET parameters were associated with progression free survival (PFS) or overall survival (OS).

Results
Median follow-up of the study group was 50 months. Six of the 30 patients progressed clinically. Absolute value PET parameters from pre-treatment scans were not significant. Absolute value SUVmax from interim-treatment scans was associated with OS as determined by univariate analysis (p < 0.01). All four calculated PET parameters (interim/pre-treatment values) were associated with OS: MTVint/pre (p < 0.01), SUVmeanint/pre (p < 0.05), SUVmaxint/pre (p = 0.01), and iSUVint/pre (p < 0.01). Absolute value SUVmax from interim-treatment scans was associated with PFS (p = 0.01). Three calculated PET parameters (int/pre-treatment values) were associated with PFS: MTVint/pre (p = 0.01), SUVmaxint/pre (p = 0.02) and iSUVint/pre (p = 0.01). IPS was associated with PFS (p < 0.05) and OS (p < 0.01).

Conclusions
Calculated PET metrics may provide predictive information beyond that of traditional clinical factors and may identify patients at high risk of treatment failure early for treatment intensification.
Proteomic analysis of the ventral disc of Giardia lamblia
Authors: Lourenço Daniela , Andrade Iamara da Silva , Terra Letícia Labati , Guimarães Patricia Ramos , Zingali Russolina Benedeta , de Souza Wanderley 
Published: January 2012

Abstract

Background

Giardia lamblia is a multiflagellated protozoan that inhabits the small intestine of vertebrates, causing giardiasis. To colonize the small intestine, the trophozoites form of the parasite remains attached to intestinal epithelial cells by means of cytoskeletal elements that form a structure known as the ventral disc. Previous studies have shown that the ventral disc is made of tubulin and giardins.

Results
To obtain further information on the composition of the ventral disc, we developed a new protocol and evaluated the purity of the isolation by transmission electron microscopy. Using 1D- and 2D-PAGE and mass spectrometry, we identified proteins with functions associated with the disc. In addition to finding tubulin and giardin, proteins known to be associated with the ventral disc, we also identified proteins annotated in the Giardia genome, but whose function was previously unknown.

Conclusions
The isolation of the ventral disc shown in this work, compared to previously published protocols, proved to be more efficient. Proteomic analysis showed the presence of several proteins whose further characterization may help in the elucidation of the mechanisms involved in the attachment of the protozoan to epithelial cells.
The loci recommended as universal barcodes for plants on the basis of floristic studies may not work with congeneric species as exemplified by DNA barcoding of Dendrobium species
Authors: Singh Hemant Kumar , Parveen Iffat , Raghuvanshi Saurabh , Babbar Shashi B 
Published: January 2012

Abstract

Background
Based on the testing of several loci, predominantly against floristic backgrounds, individual or different combinations of loci have been suggested as possible universal DNA barcodes for plants. The present investigation was undertaken to check the applicability of the recommended locus/loci for congeneric species with Dendrobium species as an illustrative example.

Results
Six loci, matK, rbcL, rpoB, rpoC1, trnH-psbA spacer from the chloroplast genome and ITS, from the nuclear genome, were compared for their amplification, sequencing and species discrimination success rates among multiple accessions of 36 Dendrobium species. The trnH-psbA spacer could not be considered for analysis as good quality sequences were not obtained with its forward primer. Among the tested loci, ITS, recommended by some as a possible barcode for plants, provided 100% species identification. Another locus, matK, also recommended as a universal barcode for plants, resolved 80.56% species. ITS remained the best even when sequences of investigated loci of additional Dendrobium species available on the NCBI GenBank (93, 33, 20, 18 and 17 of ITS, matK, rbcL, rpoB and rpoC1, respectively) were also considered for calculating the percent species resolution capabilities. The species discrimination of various combinations of the loci was also compared based on the 36 investigated species and additional 16 for which sequences of all the five loci were available on GenBank. Two-locus combination of matK+rbcL recommended by the Plant Working Group of Consortium for Barcoding of Life (CBOL) could discriminate 86.11% of 36 species. The species discriminating ability of this barcode was reduced to 80.77% when additional sequences available on NCBI were included in the analysis. Among the recommended combinations, the barcode based on three loci - matK, rpoB and rpoC1- resolved maximum number of species.

Conclusions
Any recommended barcode based on the loci tested so far, is not likely to provide 100% species identification across the plant kingdom and thus is not likely to act as a universal barcode. It appears that barcodes, if based on single or limited locus(i), would be taxa specific as is exemplified by the success of ITS among Dendrobium species, though it may not be suitable for other plants because of the problems that are discussed.
High-level tolerance to triclosan may play a role in Pseudomonas aeruginosa antibiotic resistance in immunocompromised hosts: evidence from outbreak investigation
Authors: D'Arezzo Silvia , Lanini Simone , Puro Vincenzo , Ippolito Giuseppe , Visca Paolo 
Published: January 2012

Abstract

Background and methods

Pseudomonas aeruginosa is a major infectious threat to immunocompromised patients. We recently reported a fatal epidemic of multidrug-resistant P. aeruginosa in an onchoematology unit, linked to massive contamination of a triclosan-based disinfectant. The aim of this study is to evaluate the antimicrobial activity of triclosan and chlorhexidine digluconate against the epidemic strain of P. aeruginosa, to confirm the hypothesis that the soap dispenser acted as a continuous source of the infection during the outbreak, and to explore the potential role of triclosan in increasing the level of resistance to selected antibiotics.
Susceptibility tests and time-kill assays for disinfectans were performed using two commercial formulations containing triclosan and chlorhexidine digluconate, respectively. Antibiotic susceptibility testing was performed by the broth microdilution method.

Findings
The P. aeruginosa epidemic strain exhibited an extremely high level of triclosan resistance (apparent MIC = 2,125 mg/L), while it was markedly susceptible to chlorhexidine digluconate (apparent MIC = 12.5 mg/L). Upon gradual adaptation to triclosan, the epidemic strain survived for a long period (> 120 h) in the presence of 3,400 mg/L (equivalent to 1.6 × MIC) of triclosan, concomitantly increasing the resistance to six antibiotics that are typical substrates of drug efflux pumps of the resistance nodulation division family. This effect was reversed by efflux pump inhibitors.

Conclusions
The epidemic P. aeruginosa strain was resistant to triclosan and its previous exposure to triclosan increases antibiotic resistance, likely through active efflux mechanisms. Since P. aeruginosa can become tolerant to elevated triclosan concentrations, the use of triclosan-based disinfectants should be avoided in those healthcare settings hosting patients at high risk for P. aeruginosa infection.
Heart Failure Is a Clinically and Densitometrically Independent Risk Factor for Osteoporotic Fractures: Population-Based Cohort Study of 45,509 Subjects
Authors: Majumdar Sumit R. , Ezekowitz Justin A. , Lix Lisa M. , Leslie William D. 
Published: January 2012

Objective:
The aim of the study was to determine whether heart failure is associated with an increased risk of major osteoporotic fractures that is independent of bone mineral density (BMD).

Methods:
We conducted a population-based cohort study in Manitoba, Canada, by linking a clinical registry of all adults 50 yr of age and older who underwent initial BMD testing from 1998–2009 with administrative databases. We collected osteoporosis risk factors, comorbidities, medications, and BMD results. Validated algorithms identified recent-onset heart failure before the BMD test and new fractures after. The main outcome was time to major osteoporotic fractures (i.e. clinical vertebrae, distal forearm, humerus, and hip), and multivariable proportional hazards models were used for analyses.

Results:
The cohort consisted of 45,509 adults; 1,841 (4%) had recent-onset heart failure. Subjects with heart failure were significantly (P &lt; 0.001) older (74 vs. 66 yr) and had more previous fractures (21 vs. 13%) and lower total hip BMD [T-score, −1.3 (sd 1.3) vs. −0.9 (sd 1.2)] than those without. There were 2703 incident fractures over the 5-yr observation. Overall, 10% of heart failure subjects had incident major fractures compared with 5% of those without [unadjusted hazard ratio (HR), 2.45; 95% confidence interval (CI), 2.11–2.85]. Adjustment for osteoporosis risk factors, comorbidities, and medications attenuated but did not eliminate this association (HR, 1.33; 95% CI, 1.11–1.60), nor did further adjustment for total hip BMD (HR, 1.28; 95% CI, 1.06–1.53).

Conclusions:
Heart failure is associated with a 30% increase in major fractures that is independent of traditional risk factors and BMD, and it also identifies a high-risk population that may benefit from increased screening and treatment for osteoporosis.
Bone bruise, lipohemarthrosis, and joint effusion in CT of non-displaced hip fracture
Authors: Geijer Mats , Dunker Dennis , Collin David , Göthlin Jan H 
Published: January 2012

BackgroundA suspected occult hip fracture after normal radiography is not uncommon in an elderly person after a fall. Despite a lack of robust validation in the literature, computed tomography (CT) is often used as secondary imaging.PurposeTo assess the frequency and clinical utility of non-cortical skeletal and soft tissue lesions as ancillary fracture signs in CT diagnosis of occult hip fractures.Material and MethodsAll fracture signs (cortical and trabecular fractures, bone bruise, joint effusion, and lipohemarthrosis) were recorded in 231 hip low-energy trauma cases with CT performed after normal or equivocal radiography in two trauma centers.ResultsThere were no fracture signs in 110 patients. Twelve of these had a joint effusion. In 121 patients with 46 cervical hip fractures and 75 trochanteric fractures one or more fracture signs were present. Cortical fractures were found in 115 patients. Bone bruise was found in 119 patients, joint effusion in 35, and lipohemarthrosis in 20 patients.ConclusionAncillary signs such as bone bruise and lipohemarthrosis can strengthen and sometimes indicate the diagnosis in CT of occult hip fractures. Joint effusion is a non-specific sign.
Are Routine Ancillary Stains Required to Diagnose Helicobacter Infection in Gastric Biopsy Specimens?
Authors: Hartman Douglas J. , Owens Scott R. 
Published: January 2012

Abstract
Gastric biopsies are often done to evaluate for Helicobacter gastritis. Given the oncogenic association with Helicobacter gastritis and the relative ease of therapy, it is important for pathology departments to identify all positive cases. We describe an institutional quality assurance study of an institutional method for the diagnosis of Helicobacter gastritis. We reviewed 356 gastric biopsy specimens from a 4-week period at 1 institution. Approximately half were evaluated by 4 methods, H&E stain, Giemsa stain, Warthin-Starry stain, and Helicobacter immunostain, while the remainder were stained only with H&E and Helicobacter immunostains. There were 30 cases of Helicobacter gastritis diagnosed; about 83% of cases were diagnosed on the initial H&E-stained slides. Our study highlights a quality assurance study and a head-to head comparison of 4 methods not previously reported and supports the use of ancillary stains at the discretion of the sign-out pathologist.