328 research outputs found
Multiple ITS Copies Reveal Extensive Hybridization within Rheum (Polygonaceae), a Genus That Has Undergone Rapid Radiation
During adaptive radiation events, characters can arise multiple times due to parallel evolution, but transfer of traits through hybridization provides an alternative explanation for the same character appearing in apparently non-sister lineages. The signature of hybridization can be detected in incongruence between phylogenies derived from different markers, or from the presence of two divergent versions of a nuclear marker such as ITS within one individual.In this study, we cloned and sequenced ITS regions for 30 species of the genus Rheum, and compared them with a cpDNA phylogeny. Seven species contained two divergent copies of ITS that resolved in different clades from one another in each case, indicating hybridization events too recent for concerted evolution to have homogenised the ITS sequences. Hybridization was also indicated in at least two further species via incongruence in their position between ITS and cpDNA phylogenies. None of the ITS sequences present in these nine species matched those detected in any other species, which provides tentative evidence against recent introgression as an explanation. Rheum globulosum, previously indicated by cpDNA to represent an independent origin of decumbent habit, is indicated by ITS to be part of clade of decumbent species, which acquired cpDNA of another clade via hybridization. However decumbent and glasshouse morphology are confirmed to have arisen three and two times, respectively.These findings suggested that hybridization among QTP species of Rheum has been extensive, and that a role of hybridization in diversification of Rheum requires investigation
Protein C Mutation (A267T) Results in ER Retention and Unfolded Protein Response Activation
BACKGROUND: Protein C (PC) deficiency is associated with a high risk of venous thrombosis. Recently, we identified the PC-A267T mutation in a patient with PC deficiency and revealed by in vitro studies decreased intracellular and secreted levels of the mutant. The aim of the present study was to characterize the underlying mechanism(s). METHODOLOGY/PRINCIPAL FINDINGS: CHO-K1 cells stably expressing the wild-type (PC-wt) or the PC mutant were generated. In order to examine whether the PC mutant was subjected to increased intracellular degradation, the cells were treated with several inhibitors of various degradation pathways and pulse-chase experiments were performed. Protein-chaperone complexes were analyzed by treating the cells with a cross-linker followed by Western blotting (WB). Expression levels of the immunoglobulin-binding protein (BiP) and the phosphorylated eukaryotic initiation factor 2α (P-eIF2α), both common ER stress markers, were determined by WB to examine if the mutation induced ER stress and unfolded protein response (UPR) activation. We found no major differences in the intracellular degradation between the PC variants. The PC mutant was retained in the endoplasmic reticulum (ER) and had increased association with the Grp-94 and calreticulin chaperones. Retention of the PC-A267T in ER resulted in UPR activation demonstrated by increased expression levels of the ER stress markers BiP and P-eIF2α and caused also increased apoptotic activity in CHO-K1 cells as evidenced by elevated levels of DNA fragmentation. CONCLUSIONS/SIGNIFICANCE: The reduced intracellular level and impaired secretion of the PC mutant were due to retention in ER. In contrast to other PC mutations, retention of the PC-A267T in ER resulted in minor increased proteasomal degradation, rather it induced ER stress, UPR activation and apoptosis
Genomic aberrations associated with outcome in anaplastic oligodendroglial tumors treated within the EORTC phase III trial 26951
Despite similar morphological aspects, anaplastic oligodendroglial tumors (AOTs) form a heterogeneous clinical subgroup of gliomas. The chromosome arms 1p/19q codeletion has been shown to be a relevant biomarker in AOTs and to be perfectly exclusive from EGFR amplification in gliomas. To identify new genomic regions associated with prognosis, 60 AOTs from the EORTC trial 26951 were analyzed retrospectively using BAC-array-based comparative genomic hybridization. The data were processed using a binary tree method. Thirty-three BACs with prognostic value were identified distinguishing four genomic subgroups of AOTs with different prognosis (p < 0.0001). Type I tumors (25%) were characterized by: (1) an EGFR amplification, (2) a poor prognosis, (3) a higher rate of necrosis, and (4) an older age of patients. Type II tumors (21.7%) had: (1) loss of prognostic BACs located on 1p tightly associated with 19q deletion, (2) a longer survival, (3) an oligodendroglioma phenotype, and (4) a frontal location in brain. Type III AOTs (11.7%) exhibited: (1) a deletion of prognostic BACs located on 21q, and (2) a short survival. Finally, type IV tumors (41.7%) had different genomic patterns and prognosis than type I, II and III AOTs. Multivariate analysis showed that genomic type provides additional prognostic data to clinical, imaging and pathological features. Similar results were obtained in the cohort of 45 centrally reviewed–validated cases of AOTs. Whole genome analysis appears useful to screen the numerous genomic abnormalities observed in AOTs and to propose new biomarkers particularly in the non-1p/19q codeleted AOTs
Current challenges in software solutions for mass spectrometry-based quantitative proteomics
This work was in part supported by the PRIME-XS project, grant agreement number 262067, funded by the European Union seventh Framework Programme; The Netherlands Proteomics Centre, embedded in The Netherlands Genomics Initiative; The Netherlands Bioinformatics Centre; and the Centre for Biomedical Genetics (to S.C., B.B. and A.J.R.H); by NIH grants NCRR RR001614 and RR019934 (to the UCSF Mass Spectrometry Facility, director: A.L. Burlingame, P.B.); and by grants from the MRC, CR-UK, BBSRC and Barts and the London Charity (to P.C.
Claw and limb disorders in 12 Norwegian beef-cow herds
<p>Abstract</p> <p>Background</p> <p>The main aim of the study was to assess the prevalence of claw and limb disorders in Norwegian beef-cow herds.</p> <p>Methods</p> <p>Twenty-six herds with ≥15 cow-years were selected by computerized systematic assignment from the three most beef cattle-dense regions of Norway. The study population consisted of 12 herds with 28 heifers and 334 cows. The animals were trimmed and examined once by claw trimmers during the late winter and spring of 2003. The seven claw trimmers had been taught diagnosing and recording of claw lesions. Environment, feeding and management routines, age and breed, culling and carcass characteristics were also recorded.</p> <p>Results</p> <p>Lameness was recorded in 1.1% of the animals, and only in hind claws. Pericarpal swellings were recorded in one animal and peritarsal lesions in none. In total, claw and limb disorders including lameness were recorded in 29.6% of the animals, 4.1% with front and 28.2% with hind limb disorders, respectively. Most lesions were mild. Laminitis-related claw lesions were recorded in 18.0% of the animals and infectious lesions in 16.6%. The average claw length was 84 mm in front claws and 89 mm in hind claw. Both laminitis-related and infectious claw lesions were more prevalent with increasing age. Carcasses from animals with claw and limb disorders were on average 34 kg heavier than carcasses from animals without such disorders (p = 0.02). Our results also indicate association between some management factors and claw lesions.</p> <p>Conclusion</p> <p>The study shows that the prevalence of lameness was low in 12 Norwegian beef-cow herds compared to beef-cattle herds in other countries and also that there were less claw and limb disorders in these herds compared to foreign dairy-cattle herds. The prevalence of lameness and white-line fissures was approximately the same as in Norwegian dairy herds whereas less dermatitis, heel-horn erosions, haemorrhages of the sole and the white line and sole ulcers were recorded.</p
Study of the reaction e^{+}e^{-} -->J/psi\pi^{+}\pi^{-} via initial-state radiation at BaBar
We study the process with
initial-state-radiation events produced at the PEP-II asymmetric-energy
collider. The data were recorded with the BaBar detector at center-of-mass
energies 10.58 and 10.54 GeV, and correspond to an integrated luminosity of 454
. We investigate the mass
distribution in the region from 3.5 to 5.5 . Below 3.7
the signal dominates, and above 4
there is a significant peak due to the Y(4260). A fit to
the data in the range 3.74 -- 5.50 yields a mass value
(stat) (syst) and a width value (stat)(syst) for this state. We do not
confirm the report from the Belle collaboration of a broad structure at 4.01
. In addition, we investigate the system
which results from Y(4260) decay
Low serum creatinine is associated with type 2 diabetes in morbidly obese women and men: a cross-sectional study
<p>Abstract</p> <p>Background</p> <p>Low skeletal muscle mass is associated with insulin resistance and metabolic syndrome. Serum creatinine may serve as a surrogate marker of muscle mass, and a possible relationship between low serum creatinine and type 2 diabetes has recently been demonstrated. We aimed to validate this finding in a population of Caucasian morbidly obese subjects.</p> <p>Methods</p> <p>Cross-sectional study of 1,017 consecutive morbidly obese patients with an estimated glomerular filtration rate >60 ml/min/1.73 m<sup>2</sup>. Logistic regression (univariate and multiple) was used to assess the association between serum creatinine and prevalent type 2 diabetes, including statistically testing for the possibility of non-linearity in the relationship by implementation of Generalized Additive Models (GAM) and piecewise linear regression. Possible confounding variables such as age, family history of diabetes, waist-to-hip ratio, hypertension, current smoking, serum magnesium, albuminuria and insulin resistance (log HOMA-IR) were adjusted for in three separate multiple logistic regression models.</p> <p>Results</p> <p>The unadjusted GAM analysis suggested a piecewise linear relationship between serum creatinine and diabetes. Each 1 μmol/l increase in serum creatinine was associated with 6% (95% CI; 3%-8%) and 7% (95% CI; 2%-13%) lower odds of diabetes below serum creatinine levels of 69 and 72 μmol/l in women and men, respectively. Above these breakpoints the serum creatinine concentrations did not reduce the odds further. Adjustments for non-modifiable and modifiable risk factors left the piecewise effect for both women and men largely unchanged. In the fully adjusted model, which includes serum magnesium, albuminuria and log HOMA-IR, the piecewise effect for men was statistically non-significant, but it remained present for women. Patients with creatinine levels below median had approximately 50% (women) and 75% (men) increased odds of diabetes.</p> <p>Conclusions</p> <p>Low serum creatinine is a predictor of type 2 diabetes in Caucasian morbidly obese patients, independent of age, gender, family history of diabetes, anthropometric measures, hypertension, and current smoking. Longitudinal studies of both obese and non-obese populations are needed to investigate whether serum creatinine may be causally linked with type 2 diabetes, and if so, precisely how they are linked.</p
Restriction of HIV-1-based lentiviral vectors in adult primary marrow-derived and peripheral mobilized human CD34+ hematopoietic stem and progenitor cells occurs prior to viral DNA integration
A Prominent Role for DC-SIGN+ Dendritic Cells in Initiation and Dissemination of Measles Virus Infection in Non-Human Primates
Measles virus (MV) is a highly contagious virus that is transmitted by aerosols. During systemic infection, CD150+T and B lymphocytes in blood and lymphoid tissues are the main cells infected by pathogenic MV. However, it is unclear which cell types are the primary targets for MV in the lungs and how the virus reaches the lymphoid tissues. In vitro studies have shown that dendritic cell (DC) C-type lectin DC-SIGN captures MV, leading to infection of DCs as well as transmission to lymphocytes. However, evidence of DC-SIGN-mediated transmission in vivo has not been established. Here we identified DC-SIGNhiDCs as first target cells in vivo and demonstrate that macaque DC-SIGN functions as an attachment receptor for MV. Notably, DC-SIGNhicells from macaque broncho-alveolar lavage and lymph nodes transmit MV to B lymphocytes, providing in vivo support for an important role for DCs in both initiation and dissemination of MV infection
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