bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficient disruption of Zebrafish genes using a Gal4-containing gene trap
Authors: Balciuniene Jorune , Nagelberg Danielle , Walsh Kathleen T , Camerota Diana , Georlette Daphné , Biemar Frédéric , Bellipanni Gianfranco , Balciunas Darius
Published: September 2013

Background

External development and optical transparency of embryos make zebrafish exceptionally suitable for in vivo insertional mutagenesis using fluorescent proteins to visualize expression patterns of mutated genes. Recently developed Gene Breaking Transposon (GBT) vectors greatly improve the fidelity and mutagenicity of transposon-based gene trap vectors.

Results

We constructed and tested a bipartite GBT vector with Gal4-VP16 as the primary gene trap reporter. Our vector also contains a UAS:eGFP cassette for direct detection of gene trap events by fluorescence. To confirm gene trap events, we generated a UAS:mRFP tester line. We screened 270 potential founders and established 41 gene trap lines. Three of our gene trap alleles display homozygous lethal phenotypes ranging from embryonic to late larval: nsf 
tpl6
, atp1a3a

tpl10
and flr

tpl19
. Our gene trap cassette is flanked by direct loxP sites, which enabled us to successfully revert nsf 
tpl6
, atp1a3a

tpl10
and flr

tpl19
gene trap alleles by injection of Cre mRNA. The UAS:eGFP cassette is flanked by direct FRT sites. It can be readily removed by injection of Flp mRNA for use of our gene trap alleles with other tissue-specific GFP-marked lines. The Gal4-VP16 component of our vector provides two important advantages over other GBT vectors. The first is increased sensitivity, which enabled us to detect previously unnoticed expression of nsf in the pancreas. The second advantage is that all our gene trap lines, including integrations into non-essential genes, can be used as highly specific Gal4 drivers for expression of other transgenes under the control of Gal4 UAS.

Conclusions

The Gal4-containing bipartite Gene Breaking Transposon vector presented here retains high specificity for integrations into genes, high mutagenicity and revertibility by Cre. These features, together with utility as highly specific Gal4 drivers, make gene trap mutants presented here especially useful to the research community.
A combination of improved differential and global RNA-seq reveals pervasive transcription initiation and events in all stages of the life-cycle of functional RNAs in Propionibacterium acnes, a major contributor to wide-spread human disease
Authors: Lin Yu-fei , A David Romero , Guan Shuang , Mamanova Lira , McDowall Kenneth J
Published: September 2013

Background

Sequencing of the genome of Propionibacterium acnes produced a catalogue of genes many of which enable this organism to colonise skin and survive exposure to the elements. Despite this platform, there was little understanding of the gene regulation that gives rise to an organism that has a major impact on human health and wellbeing and causes infections beyond the skin. To address this situation, we have undertaken a genome–wide study of gene regulation using a combination of improved differential and global RNA-sequencing and an analytical approach that takes into account the inherent noise within the data.

Results

We have produced nucleotide-resolution transcriptome maps that identify and differentiate sites of transcription initiation from sites of stable RNA processing and mRNA cleavage. Moreover, analysis of these maps provides strong evidence for ‘pervasive’ transcription and shows that contrary to initial indications it is not biased towards the production of antisense RNAs. In addition, the maps reveal an extensive array of riboswitches, leaderless mRNAs and small non-protein-coding RNAs alongside vegetative promoters and post-transcriptional events, which includes unusual tRNA processing. The identification of such features will inform models of complex gene regulation, as illustrated here for ribonucleotide reductases and a potential quorum-sensing, two-component system.

Conclusions

The approach described here, which is transferable to any bacterial species, has produced a step increase in whole-cell knowledge of gene regulation in P. acnes. Continued expansion of our maps to include transcription associated with different growth conditions and genetic backgrounds will provide a new platform from which to computationally model the gene expression that determines the physiology of P. acnes and its role in human disease.
Leaf cDNA-AFLP analysis of two citrus species differing in manganese tolerance in response to long-term manganese-toxicity
Authors: Zhou Chen-Ping , Qi Yi-Ping , You Xiang , Yang Lin-Tong , Guo Peng , Ye Xin , Zhou Xin-Xing , Ke Feng-Jiao , Chen Li-Song
Published: September 2013

Background

Very little is known about manganese (Mn)-toxicity-responsive genes in citrus plants. Seedlings of ‘Xuegan’ (Citrus sinensis) and ‘Sour pummelo’ (Citrus grandis) were irrigated for 17 weeks with nutrient solution containing 2 μM (control) or 600 μM (Mn-toxicity) MnSO4. The objectives of this study were to understand the mechanisms of citrus Mn-tolerance and to identify differentially expressed genes, which might be involved in Mn-tolerance.

Results

Under Mn-toxicity, the majority of Mn in seedlings was retained in the roots; C. sinensis seedlings accumulated more Mn in roots and less Mn in shoots (leaves) than C. grandis ones and Mn concentration was lower in Mn-toxicity C. sinensis leaves compared to Mn-toxicity C. grandis ones. Mn-toxicity affected C. grandis seedling growth, leaf CO2 assimilation, total soluble concentration, phosphorus (P) and magenisum (Mg) more than C. sinensis. Using cDNA-AFLP, we isolated 42 up-regulated and 80 down-regulated genes in Mn-toxicity C. grandis leaves. They were grouped into the following functional categories: biological regulation and signal transduction, carbohydrate and energy metabolism, nucleic acid metabolism, protein metabolism, lipid metabolism, cell wall metabolism, stress responses and cell transport. However, only 7 up-regulated and 8 down-regulated genes were identified in Mn-toxicity C. sinensis ones. The responses of C. grandis leaves to Mn-toxicity might include following several aspects: (1) accelerating leaf senescence; (2) activating the metabolic pathway related to ATPase synthesis and reducing power production; (3) decreasing cell transport; (4) inhibiting protein and nucleic acid metabolisms; (5) impairing the formation of cell wall; and (6) triggering multiple signal transduction pathways. We also identified many new Mn-toxicity-responsive genes involved in biological and signal transduction, carbohydrate and protein metabolisms, stress responses and cell transport.

Conclusions

Our results demonstrated that C. sinensis was more tolerant to Mn-toxicity than C. grandis, and that Mn-toxicity affected gene expression far less in C. sinensis leaves. This might be associated with more Mn accumulation in roots and less Mn accumulation in leaves of Mn-toxicity C. sinensis seedlings than those of C. grandis seedlings. Our findings increase our understanding of the molecular mechanisms involved in the responses of plants to Mn-toxicity.
Comparison of microbial diversity determined with the same variable tag sequence extracted from two different PCR amplicons
Authors: He Yan , Zhou Ben-Jie , Deng Guan-Hua , Jiang Xiao-Tao , Zhang Hai , Zhou Hong-Wei
Published: September 2013

Background

Deep sequencing of the variable region of 16S rRNA genes has become the predominant tool for studying microbial ecology. As sequencing datasets have accumulated, meta-analysis of sequences obtained with different variable 16S rRNA gene targets and by different sequencing methods has become an intriguing prospect that remains to be evaluated experimentally.

Results

We amplified a group of fecal samples using both V4F-V6R and V6F-V6R primer sets, excised the same V6 fragment from the two sets of Illumina sequencing data, and compared the resulting data in terms of the α-diversity, β-diversity, and community structure. Principal component analysis (PCA) comparing the microbial community structures of different datasets, including those with simulated sequencing errors, was very reliable. Procrustes analysis showed a high degree of concordance between the different datasets for both abundance-weighted and binary Jaccard distances (P < 0.05), and a meta-analysis of individual datasets resulted in similar conclusions. The Shannon’s diversity index was consistent as well, with comparable values obtained for the different datasets and for the meta-analysis of different datasets. In contrast, richness estimators (OTU and Chao) varied significantly, and the meta-analysis of richness estimators was also biased. The community structures of the two datasets were obviously different and led to significant changes in the biomarkers identified by the LEfSe statistical tool.

Conclusions

Our results suggest that beta-diversity analysis and Shannon’s diversity are relatively reliable for meta-analysis, while community structures and biomarkers are less consistent. These results should be useful for future meta-analyses of microbiomes from different data sources.
Pre-existing Schistosoma japonicum infection alters the immune response to Plasmodium berghei infection in C57BL/6 mice
Authors: Wang Mei-lian , Cao Ya-ming , Luo En-jie , Zhang Ying , Guo Ya-jun
Published: September 2013

Background

Since helminths and malaria parasites are often co-endemic, it is important to clarify the immunoregulatory mechanism that occurs during the process of co-infection. A previous study confirmed that dendritic cells (DCs) are involved in the establishment and regulation of the T-cell-mediated immune response to malaria infection. In the current study, distinct response profiles for splenic DCs and regulatory T cell (Treg) responses were assessed to evaluate the effects of a pre-existing Schistosoma japonicum infection on malaria infection.

Methods

Malaria parasitaemia, survival rate, brain histopathology and clinical experimental cerebral malaria (ECM) were assessed in both Plasmodium berghei ANKA-mono-infected and S. japonicum-P. berghei ANKA-co-infected mice. Cell surface/intracellular staining and flow cytometry were used to analyse the level of splenic DC subpopulations, toll-like receptors (TLRs), DC surface molecules, Tregs (CD4+CD25+Foxp3+), IFN-γ/IL-10-secreting Tregs, and IFN-γ+/IL-10+-Foxp3-CD4+ T cells. IFN-γ, IL-4, IL-5, IL-10 and IL-13 levels were determined in splenocyte supernatants using enzyme-linked immunosorbent assay (ELISA).

Results

The co-infected mice had significantly higher malaria parasitaemia, compared with the mono-infected mice, on days 2, 3, 7 and 8 after P. berghei ANKA infection. M ono-infected mice had a slightly lower survival rate, while clinical ECM symptoms, and brain pathology, were significantly more severe during the period of susceptibility to ECM. On days 5 and 8 post P. berghei ANKA infection, co-infected mice had significantly lower levels of CD11c+CD11b+, CD11c+CD45R/B220+, CD11c+TLR4+, CD11c+TLR9+, CD11c+MHCII+, CD11c+CD86+, IFN-γ-secreting Tregs, and IFN-γ+Foxp3-CD4+ T cells in single-cell suspensions of splenocytes when compared with P. berghei ANKA-mono-infected mice. Co-infected mice also had significantly lower levels of IFN-γ and higher levels of IL-4, IL-5, and IL-13 in splenocyte supernatants compared to mono-infected mice. There were no differences in the levels of IL-10-secreting Tregs or IL-10+Foxp3-CD4+ T cells between co-infected and mono-infected mice.

Conclusions

A Tregs-associated Th2 response plays an important role in protecting against ECM pathology. Pre-existing S. japonicum infection suppressed TLR ligand-induced DC maturation and had an anti-inflammatory effect during malaria infection not only by virtue of its ability to induce Th2 responses, but also by directly suppressing the ability of DC to produce pro-inflammatory mediators.
Homology modeling and ligand docking of Mitogen-activated protein kinase-activated protein kinase 5 (MK5)
Authors: Lindin Inger , Wuxiuer Yimingjiang , Kufareva Irina , Abagyan Ruben , Moens Ugo , Sylte Ingebrigt , Ravna Aina Westrheim
Published: September 2013

Background

Mitogen-activated protein kinase-activated protein kinase 5 (MK5) is involved in one of the major signaling pathways in cells, the mitogen-activated protein kinase pathway. MK5 was discovered in 1998 by the groups of Houng Ni and Ligou New, and was found to be highly conserved throughout the vertebrates. Studies, both in vivo and in vitro, have shown that it is implicated in tumor suppression as well as tumor promotion, embryogenesis, anxiety, locomotion, cell motility and cell cycle regulation.

Methods

In order to obtain a molecular model of MK5 that can be used as a working tool for development of chemical probes, three MK5 models were constructed and refined based on three different known crystal structures of the closely related MKs; MK2 [PDB: 2OZA and PDB: 3M2W] and MK3 [PDB: 3FHR]. The main purpose of the present MK5 molecular modeling study was to identify the best suited template for making a MK5 model. The ability of the generated models to effectively discriminate between known inhibitors and decoys was analyzed using receiver operating characteristic (ROC) curves.

Results

According to the ROC curve analyzes, the refined model based on 3FHR was most effective in discrimination between known inhibitors and decoys.

Conclusions

The 3FHR-based MK5 model may serve as a working tool for development of chemical probes using computer aided drug design. The biological function of MK5 still remains elusive, but its role as a possible drug target may be elucidated in the near future.
Dengue 2 infection of HepG2 liver cells results in endoplasmic reticulum stress and induction of multiple pathways of cell death
Authors: Thepparit Chutima , Khakpoor Atefeh , Khongwichit Sarawut , Wikan Nitwara , Fongsaran Chanida , Chingsuwanrote Pimjai , Panraksa Patcharee , Smith Duncan R
Published: September 2013

Background

A number of studies have implicated the direct involvement of the liver in dengue virus (DENV) infection, and it has been widely shown that liver cells subsequently undergo apoptosis. The mechanism by which liver cells undergo apoptosis in response to DENV infection remains unclear. To provide further information on the mechanism of apoptosis in DENV infected liver cells, HepG2 cells were infected with DENV 2 and analyzed for the induction of ER stress, apoptosis and autophagy.

Results

In response to DENV infection, HepG2 cells showed the induction of both the ER resident unfolded protein response as well as the Noxa/PUMA stress response pathways. Proteolytic activation of caspases 4, 7, 8 and 9 was observed as well as changes in mitochondrial transmembrane potential. Increased monodansylcadaverine staining was observed in DENV infected cells, consistent with the previously reported induction of autophagy.

Conclusions

These results are consistent with a model in which the induction of multiple ER stress pathways is coupled with the induction of multiple cell death pathways as a mechanism to ensure the removal of infected liver cells from the system.
Time course of soluble P-selectin and von Willebrand factor levels in trauma patients: a prospective observational study
Authors: Tang Ning , Yin Shiyu , Sun Ziyong , Pan Yingying
Published: September 2013

Background

Coagulopathy often develops in patients with serious trauma and is correlated with the clinical outcome. The contribution of platelet activity and endothelial dysfunction to trauma-induced coagulopathy remain to be defined. The purpose of this study was to investigate the time courses of soluble P-selectin (sPsel, an index of platelet activation) and von Willebrand factor (VWF, an index of endothelial dysfunction) in trauma patients and elucidate their relationship to coagulation parameter levels, the presence of coagulopathy, and patient outcome.

Methods

This prospective observational study, which took place in a university hospital intensive care unit (ICU), included 82 severely injured trauma patients. The sPsel, VWF antigen, protein C, and factor VII levels were measured and routine coagulation tests were performed upon admission to ICU and daily within the first week. The 30-day mortality rate was also determined.

Results

Thirty-seven (45.1%) patients developed coagulopathy upon admission to the ICU, and the 30-day mortality rate was 20.7% (n = 17). Both the admission sPsel and VWF levels were lower in patients with coagulopathy than in those without (p < 0.05) and were significantly correlated with the protein C and factor VII levels, respectively (all p < 0.05). The VWF levels were lower during the first 3 days and higher on day 7 after admission in nonsurvivors than in survivors (all p < 0.05). No significant differences in sPsel levels were found between nonsurvivors and survivors on each day during the first week.

Conclusion

In severely injured trauma patients in the ICU, lower levels of sPsel and VWF on admission were associated with the presence of coagulopathy and might not predict a better outcome. An increase in the VWF level at the end of the first week after admission to ICU was associated with increased 30-day mortality.
Association between radiological findings and severity of community-acquired pneumonia in children
Authors: Patria Maria Francesca , Longhi Benedetta , Lelii Mara , Galeone Carlotta , Pavesi Maria Angela , Esposito Susanna
Published: September 2013

Background

There are few published data concerning radiological findings and their relationship with community-acquired pneumonia (CAP) severity. The aim if this study was to assess radiographic findings in children with CAP of different severity in order to evaluate whether some parameters are associated with severe CAP.

Methods

We analysed the characteristics of parenchymal densities in 335 chest radiographs of otherwise healthy children (173 males; mean age ± standard deviation, 7.5 ± 4.5 years) admitted to our Emergency Room for CAP. Upon admission, chest radiographs were obtained in the two standard projections, and the children with severe or mild/moderate CAP were compared in order to identify any correlations between CAP severity and the radiological findings.

Results

Seventy-six of the 335 enrolled children (22.7%) fulfilled the criteria for severe CAP. In comparison with the children with mild/moderate CAP, in severe CAP there was a significantly greater frequency of a bilateral multifocal distribution (p = 0.01), the simultaneous involvement of ≥3 sites (p = 0.007), and the involvement of the right hilum (p = 0.02). The same results were confirmed in the multiple logistic regression model.

Conclusions

This study shows that radiological findings such as a multifocal bilateral distribution, the simultaneous involvement of at least three sites, and right hilar consolidation are associated with severe CAP in otherwise healthy children, and could be considered markers of disease severity in children with CAP.
The tumor suppressor gene DAPK2 is induced by the myeloid transcription factors PU.1 and C/EBPα during granulocytic differentiation but repressed by PML-RARα in APL
Authors: Humbert Magali , Federzoni Elena A , Britschgi Adrian , Schläfli Anna M , Valk Peter J M , Kaufmann Thomas , Haferlach Torsten , Behre Gerhard , Simon Hans-Uwe , Torbett Bruce E , Fey Martin F , Tschan Mario P
Published: September 2013

DAPK2 is a proapoptotic protein that is mostly expressed in the hematopoietic tissue. A detailed DAPK2 expression analysis in two large AML patient cohorts revealed particularly low DAPK2 mRNA levels in APL. DAPK2 levels were restored in APL patients undergoing ATRA therapy. PML-RARA is the predominant lesion in APL causing transcriptional repression of genes important for neutrophil differentiation. We found binding of PML-RARA and PU.1, a myeloid master regulator, to RARA and PU.1 binding sites in the DAPK2 promoter. Ectopic expression of PML-RARA in non-APL, as well as knocking down PU.1 in APL cells, resulted in a significant reduction of DAPK2 expression. Restoring DAPK2 expression in PU.1 knockdown APL cells partially rescued neutrophil differentiation, thereby identifying DAPK2 as a relevant PU.1 downstream effector. Moreover, low DAPK2 expression is also associated with C/EBPα-mutated AML patients, and we found C/EBPα-dependent regulation of DAPK2 during APL differentiation. In conclusion, we identified first inhibitory mechanisms responsible for the low DAPK2 expression in particular AML subtypes, and the regulation of DAPK2 by two myeloid transcription factors underlines its importance in neutrophil development.
Cost-effectiveness of injectable opioid treatmentv. oral methadone for chronic heroin addiction
Authors: Byford Sarah , Barrett Barbara , Metrebian Nicola , Groshkova Teodora , Cary Maria , Charles Vikki , Lintzeris Nicholas , Strang John
Published: September 2013

Background

Despite evidence of the effectiveness of injectable opioid treatment compared with oral methadone for chronic heroin addiction, the additional cost of injectable treatment is considerable, and cost-effectiveness uncertain.

Aims

To compare the cost-effectiveness of supervised injectable heroin and injectable methadone with optimised oral methadone for chronic refractory heroin addiction.

Method

Multisite, open-label, randomised controlled trial. Outcomes were assessed in terms of quality-adjusted life-years (QALYs). Economic perspective included health, social services and criminal justice resources.

Results

Intervention costs over 26 weeks were significantly higher for injectable heroin (mean £8995 v. £4674 injectable methadone and £2596 oral methadone;P<0.0001). Costs overall were highest for oral methadone (mean £15805 v. £13410 injectable heroin and £10945 injectable methadone;P=n.s.) due to higher costs of criminal activity. In cost-effectiveness analysis, oral methadone was dominated by injectable heroin and injectable methadone (more expensive and less effective). At willingness to pay of £30 000 per QALY, there is a higher probability of injectable methadone being more cost-effective (80%) than injectable heroin.

Conclusions

Injectable opioid treatments are more cost-effective than optimised oral methadone for chronic refractory heroin addiction. The choice between supervised injectable heroin and injectable methadone is less clear. There is currently evidence to suggest superior effectiveness of injectable heroin but at a cost that policy makers may find unacceptable. Future research should consider the use of decision analytic techniques to model expected costs and benefits of the treatments over the longer term.
Inhibitors of SCF-Skp2/Cks1 E3 Ligase Block Estrogen-Induced Growth Stimulation and Degradation of Nuclear p27kip1: Therapeutic Potential for Endometrial Cancer
Authors: Pavlides Savvas C. , Huang Kuang-Tzu , Reid Dylan A. , Wu Lily , Blank Stephanie V. , Mittal Khushbakhat , Guo Lankai , Rothenberg Eli , Rueda Bo , Cardozo Timothy , Gold Leslie I.
Published: September 2013

In many human cancers, the tumor suppressor, p27kip1 (p27), a cyclin-dependent kinase inhibitor critical to cell cycle arrest, undergoes perpetual ubiquitin-mediated proteasomal degradation by the E3 ligase complex SCF-Skp2/Cks1 and/or cytoplasmic mislocalization. Lack of nuclear p27 causes aberrant cell cycle progression, and cytoplasmic p27 mediates cell migration/metastasis. We previously showed that mitogenic 17-β-estradiol (E2) induces degradation of p27 by the E3 ligase Skp1-Cullin1-F-Box- S phase kinase-associated protein2/cyclin dependent kinase regulatory subunit 1 in primary endometrial epithelial cells and endometrial carcinoma (ECA) cell lines, suggesting a pathogenic mechanism for type I ECA, an E2-induced cancer. The current studies show that treatment of endometrial carcinoma cells-1 (ECC-1) with small molecule inhibitors of Skp2/Cks1 E3 ligase activity (Skp2E3LIs) stabilizes p27 in the nucleus, decreases p27 in the cytoplasm, and prevents E2-induced proliferation and degradation of p27 in endometrial carcinoma cells-1 and primary ECA cells. Furthermore, Skp2E3LIs increase p27 half-life by 6 hours, inhibit cell proliferation (IC50, 14.3μM), block retinoblastoma protein (pRB) phosphorylation, induce G1 phase block, and are not cytotoxic. Similarly, using super resolution fluorescence localization microscopy and quantification, Skp2E3LIs increase p27 protein in the nucleus by 1.8-fold. In vivo, injection of Skp2E3LIs significantly increases nuclear p27 and reduces proliferation of endometrial epithelial cells by 42%–62% in ovariectomized E2-primed mice. Skp2E3LIs are specific inhibitors of proteolytic degradation that pharmacologically target the binding interaction between the E3 ligase, SCF-Skp2/Cks1, and p27 to stabilize nuclear p27 and prevent cell cycle progression. These targeted inhibitors have the potential to be an important therapeutic advance over general proteasome inhibitors for cancers characterized by SCF-Skp2/Cks1-mediated destruction of nuclear p27.
Stimulated Thyroglobulin at Recombinant Human TSH-Aided Ablation Predicts Disease-free Status One Year Later
Authors: Melo Miguel , Costa Gracinda , Ribeiro Cristina , Carrilho Francisco , Martins Maria João , da Rocha Adriana Gaspar , Sobrinho-Simões Manuel , Carvalheiro Manuela , Soares Paula
Published: September 2013

Context:

Thyroglobulin (Tg) levels measured at the time of remnant ablation after thyroid hormone withdrawal (THW) were shown to have prognostic value in predicting disease-free status.

Objectives:

Our objectives were to determine whether stimulated Tg levels, measured at the time of remnant ablation performed under recombinant human TSH (rhTSH) stimulation, has value in predicting absence of detectable disease 1 year after radioiodine therapy and to compare the results obtained with this approach with a cohort of patients submitted to ablation after THW.

Design:

This was a prospective observational study.

Setting and Patients:

The study included 293 consecutive patients treated for a differentiated thyroid carcinoma with no initial evidence of distant metastasis. All patients were submitted to a total or near-total thyroidectomy, followed by ablation either under rhTSH (n = 151) or endogenous TSH stimulation (n = 142). Patients with positive Tg antibodies were excluded.

Main Outcome Measures:

The predictive value of Tg at ablation was assessed by receiver operating characteristic curve analysis.

Results:

In the rhTSH group, 96 patients (73.3%) were considered disease-free at 1 year. Stimulated Tg at ablation after rhTSH was found to be an independent prognostic indicator of disease persistence 12 months later. The highest-accuracy cutoff value for absence of detectable disease was defined as 7.2 ng/mL, with a negative predictive value of 90%. In the THW group, Tg at ablation also proved to have independent predictive value. Using the same threshold (7.2 ng/mL), the negative predictive value of Tg was 95% in the THW group.

Conclusions:

When rhTSH was used, stimulated Tg at ablation had independent predictive value for disease-free status 1 year later. A low stimulated Tg at rhTSH-aided ablation may be considered a favorable prognosis factor.
Reduced Serum Concentrations of Carboxylated and Undercarboxylated Osteocalcin Are Associated With Risk of Developing Type 2 Diabetes Mellitus in a High Cardiovascular Risk Population: A Nested Case-Control Study
Authors: Díaz-López Andrés , Bulló Mònica , Juanola-Falgarona Marti , Martínez-González Miguel A. , Estruch Ramón , Covas Maria-Isabel , Arós Fernando , Salas-Salvadó Jordi
Published: September 2013

Context and Objective:

Because it has been suggested that osteocalcin (OC), an osteoblast-derived hormone, is a new link between bone and glucose metabolism, we tested whether serum carboxylated osteocalcin (cOC) and undercarboxylated osteocalcin (ucOC) levels are independently associated with the development of type 2 diabetes in subjects at high cardiovascular risk.

Design, Setting, and Participants:

A prospective, nested case-control study was conducted using data from the Prevención con Dieta Mediterránea (PREDIMED) study. We included 153 case subjects with newly diagnosed diabetes and 306 individually matched control subjects free of diabetes identified during a mean 5-year follow-up. Conditional logistic regression models were used to estimate matched odds ratios for incident diabetes according to categories of both forms of OC measured by ELISAs.

Results:

Baseline serum concentrations of both forms of OC were significantly lower in case subjects than in control subjects. In subjects with incident cases of diabetes, concentrations of cOC, but not of ucOC, were inversely and significantly associated with homeostasis model assessment of insulin resistance levels (β = −0.335) and with fasting glucose concentrations (β = −0.044) in control subjects, independent of other relevant confounders. In the conditional logistic model that took into account the matching factors, the odds ratios for diabetes incidence in the lowest vs the highest tertile of cOC and ucOC were 2.03 (95% confidence interval, 1.32–3.13) and 1.88 (1.23–2.85), respectively. Further adjustment for family history of diabetes, lifestyle, and other confounding factors did not appreciably change the magnitude of these associations.

Conclusion:

In a population at high cardiovascular risk, low concentrations of serum cOC and ucOC were strongly associated with an increased risk of incident diabetes.
IGF-1R Modulation of Acute GH-Induced STAT5 Signaling: Role of Protein Tyrosine Phosphatase Activity
Authors: Gan Yujun , Zhang Yue , Buckels Ashiya , Paterson Andrew J. , Jiang Jing , Clemens Thomas L. , Zhang Zhong-Yin , Du Keyong , Chang Yingzi , Frank Stuart J.
Published: September 2013

GH is a potent anabolic and metabolic factor that binds its cell surface receptor (GHR), activating the GHR-associated tyrosine kinase, Janus kinase 2, which phosphorylates and activates the latent transcription factor, signal transducer and activator of transcription 5 (STAT5). Some GH actions are mediated by the elaboration of IGF-1, which exerts effects by binding and activating the heterotetrameric tyrosine kinase growth factor receptor, IGF-1R. In addition to this GH-GHR-IGF-1-IGF-1R scheme, we have demonstrated in primary osteoblasts and in islet β-cells that then deletion or silencing of IGF-1R results in diminished GH-induced STAT5 phosphorylation, suggesting that the presence of IGF-1R may facilitate GH signaling. In this study, we explore potential roles for protein tyrosine phosphatase activity in modulating GH-induced signaling, comparing conditions in which IGF-1R is present or diminished. We confirm that in mouse primary osteoblasts harboring loxP sites flanking the IGF-1R gene, infection with an adenovirus that expresses the Cre recombinase results in IGF-1R deletion and diminished acute GH-induced STAT5 phosphorylation. Furthermore, we present a new model of IGF-1R silencing, in which expression of short hairpin RNA directed at IGF-1R greatly reduces IGF-1R abundance in LNCaP human prostate cancer cells. In both models, treatment with a chemical inhibitor of protein tyrosine phosphatase-1B (PTP-1B), but not one of src homology region 2 domain-containing phosphotase-1 (SHP-1) and SHP-2, reverses the loss of GH-induced STAT5 phosphorylation in cells lacking IGF-1R but has no effect in cells with intact IGF-1R. Furthermore, expression of either a dominant-negative PTP-1B or the PTP-1B-interacting inhibitory protein, constitutive photomorphogenesis 1, also rescues acute GH-induced STAT5 signaling in IGF-1R-deficient cells but has no effect in IGF-1R replete cells. By expressing a substrate-trapping mutant PTP-1B, we demonstrate that tyrosine phosphorylated Janus kinase-2 is a PTP-1B substrate only in cells lacking IGF-1R. Collectively, our data suggest that IGF-1R positively regulates acute GH signaling by preventing access of PTP-1B activity to Janus kinase 2 and thereby preventing PTP-1B-mediated suppression of GH-induced STAT5 activation.
Interactions between the discoidin domain receptor 1 and β1 integrin regulate attachment to collagen
Authors: Staudinger Lisa A. , Spano Stephen J. , Lee Wilson , Coelho Nuno , Rajshankar Dhaarmini , Bendeck Michelle P. , Moriarty Tara , McCulloch Christopher A.
Published: September 2013

Collagen degradation by phagocytosis is essential for physiological collagen turnover and connective tissue homeostasis. The rate limiting step of phagocytosis is the binding of specific adhesion receptors, which include the integrins and discoidin domain receptors (DDR), to fibrillar collagen. While previous data suggest that these two receptors interact, the functional nature of these interactions is not defined. In mouse and human fibroblasts we examined the effects of DDR1 knockdown and over-expression on β1 integrin subunit function. DDR1 expression levels were positively associated with enhanced contraction of floating and attached collagen gels, increased collagen binding and increased collagen remodeling. In DDR1 over-expressing cells compared with control cells, there were increased numbers, area and length of focal adhesions immunostained for talin, paxillin, vinculin and activated β1 integrin. After treatment with the integrin-cleaving protease jararhagin, in comparison to controls, DDR1 over-expressing cells exhibited increased β1 integrin cleavage at the cell membrane, indicating that DDR1 over-expression affected the access and susceptibility of cell-surface β1 integrin to the protease. DDR1 over-expression was associated with increased glycosylation of the β1 integrin subunit, which when blocked by deoxymannojirimycin, reduced collagen binding. Collectively these data indicate that DDR1 regulates β1 integrin interactions with fibrillar collagen, which positively impacts the binding step of collagen phagocytosis and collagen remodeling.
Unique properties of Drosophila spermatocyte primary cilia
Authors: Riparbelli Maria Giovanna , Cabrera Oscar A. , Callaini Giuliano , Megraw Timothy L.
Published: September 2013

The primary cilium is an essential organelle required for animal development and adult homeostasis that is found on most animal cells. The primary cilium contains a microtubule-based axoneme cytoskeleton that typically grows from the mother centriole in G0/G1 phase of the cell cycle as a membrane-bound compartment that protrudes from the cell surface. A unique system of bidirectional transport, intraflagellar transport (IFT), maintains the structure and function of cilia. While the axoneme is dynamic, growing and shrinking at its tip, at the same time it is very stable to the effects of microtubule-targeting drugs. The primary cilia found on Drosophila spermatocytes diverge from the general rules of primary cilium biology in several respects. Among these unique attributes, spermatocyte cilia assemble from all four centrioles in an IFT-independent manner in G2 phase, and persist continuously through two cell divisions. Here, we show that Drosophila spermatocyte primary cilia are extremely sensitive to microtubule-targeting drugs, unlike their mammalian counterparts. Spermatocyte cilia and their axonemes fail to assemble or be maintained upon nocodazole treatment, while centriole replication appears unperturbed. On the other hand, paclitaxel (Taxol), a microtubule-stabilizing drug, disrupted transition zone assembly and anchoring to the plasma membrane while causing spermatocyte primary cilia to grow extensively long during the assembly/elongation phase, but did not overtly affect the centrioles. However, once assembled to their mature length, spermatocyte cilia appeared unaffected by Taxol. The effects of these drugs on axoneme dynamics further demonstrate that spermatocyte primary cilia are endowed with unique assembly properties.
Targeted inactivation and identification of targets of the Gli2a transcription factor in the zebrafish
Authors: Wang Xingang , Zhao Zhonghua , Muller Julius , Iyu Audrey , Khng Alexis Jiaying , Guccione Ernesto , Ruan Yijun , Ingham Philip W.
Published: September 2013

Hedgehog (Hh) signaling is mediated by the Gli transcription factors and, in the zebrafish, plays an important role in patterning both the neural tube and myotome. Using a null allele of the gli2a gene induced by targeted mutagenesis, we show that Gli2a is completely dispensable in the fish but acts redundantly with Gli1 to regulate expression of known Hh targets, such as ptch2, prdm1a and eng2a, in the myotome and neural tube. To identify novel targets of Hh signaling, we performed chromatin immunoprecipitation sequencing (ChIP-seq) of whole embryo extracts. Samples were significantly enriched for 192 genomic regions, some of which are associated with four known Hh target genes, ptch1, ptch2, gli1 and olig2. Sequence analysis of these regions reveals a high level of conservation of Gli-binding sites from fish to mammals in some, but not all, cases. Expression analysis of other transcription units that are closely associated with peaks identified several putative targets not previously implicated as Hh targets, including myl10, hnmt, lrp4, efemp2, fras1, quo, and lamc1. Each of these genes shows loss of, or reduced expression in, embryos homozygous for an antimorphic allele of gli2a, you-too (yot), consistent with their being direct targets of Gli2a.
Inflammatory challenge increases measures of oxidative stress in a free-ranging, long-lived mammal
Authors: Schneeberger Karin , Czirják Gábor Á. , Voigt Christian C.
Published: September 2013

Oxidative stress - the imbalance between reactive oxygen species (ROS) and neutralising antioxidants - has been under debate as the main cause of ageing in aerobial organisms. The level of ROS should increase during infections as part of the activation of an immune response, leading to oxidative damage on proteins, lipids and DNA. Yet, it is unknown how long-lived organisms, especially mammals, cope with oxidative stress. Bats are known to carry a variety of zoonotic pathogens and at the same time are despite their high mass-specific basal metabolic rate unusually long-lived, which may be partly caused by low oxidative damage of organs. Here, we ask if an immune challenge causes oxidative stress in free-ranging bats, measuring two oxidative stress markers. We injected 20 short-tailed fruit bats (Carollia perspicillata) with bacterial derived lipopolysaccharides (LPS) and 20 individuals with phosphate-buffered saline solution (PBS) as a control. Individuals injected with LPS showed an immune reaction by increased white blood cell count after 24h, whereas there was no significant change in leukocyte counts in control animals. The biological antioxidant potential (BAP) remained the same in both groups, but reactive oxygen metabolites (ROM) increased after treatment with LPS, indicating a significant increase in oxidative stress in animals when mounting an immune reaction toward the inflammatory challenge. Control individuals did not show a change in oxidative stress markers. We conclude that in a long-lived mammal, even high concentrations of antioxidants do not immediately neutralise free radicals produced during a cellular immune response. Thus, fighting an infection may lead to oxidative stress in bats.
Photochromic Performance of 1-Thiazolyl-2-vinylcyclopentene Derivatives Having a Phenyl- or 4-Methoxyphenyl-Substituted Olefin
Authors: Takami Shizuka , Shimizu Ayano , Shimizu Kazuyuki , Miyoshi Ryota , Yamaguchi Tadatsugu , Irie Masahiro
Published: September 2013

1-Thiazolyl-2-vinylcyclopentene derivatives, 1-(5-methoxy-2-phenyl-4-thiazolyl)-2-(2-methyl-1-phenyl-1-propenyl)perfluorocyclopentene (1a), 1-[5-methoxy-2-(4-methoxyphenyl)-4-thiazolyl]-2-(2-methyl-1-phenyl-1-propenyl)perfluorocyclopentene (2a), and 1-[5-methoxy-2-(4-methoxyphenyl)-4-thiazolyl]-2-[1-(4-methoxyphenyl)-2-methyl-1-propenyl]perfluorocyclopentene (3a) were synthesized in an attempt to obtain yellow photochromic compounds having low photocycloreversion quantum yields and large absorption coefficients of the closed-ring isomers. Their photochromic performance, thermal stability, and fatigue resistance were compared with 1-[5-methoxy-2-(4-methoxyphenyl)-4-thiazolyl]-2-(1,2-dimethyl-1-propenyl)perfluorocyclopentene (4a) having a methyl-substituted olefin. Upon irradiation with 313 nm light, compounds 1a, 2a, and 3a changed from colorless to various shades of yellow in toluene. The conversions from the open-ring (1a, 2a, and 3a) to the closed-ring (1b, 2b, and 3b) isomers in the photostationary state under irradiation with 313 nm light were 93, 95, and 98%, respectively. Among the three derivatives 3b has the largest absorption coefficient (ε = 18900 M−1 cm−1) at 428 nm and the lowest cycloreversion quantum yield of 1.8 × 10−3.
Synthesis and antitubercular evaluation of new 1,2,3-triazole derivatives of carbohydrates
Authors: Dos Santos Juliana Alves , Corrales Roberta C. N. Reis , Pavan Fernando R. , Leite Clarice Queico. F. , De Paula Dias Rafael Mafra , Da Silva Adilson David
Published: September 2013

We reported in this work the preparation of novel 1,4-disubstituted-1,2,3-triazoles derivatives from D-glucose and D-fructose and their in vitro antibacterial activity against Mycobacterium tuberculosis were evaluated. The chemical synthesis was performed based on the 1,3-dipolar cycloaddition reaction, and antimicrobial activity was determined based on Resazurin Microtiter Assay against Mycobacterium. None of the triazole glycoconjugates tested showed activity against these microorganisms.
Investigation of the Self-Diffusion Coefficients of Trivalent Gd3+ in aqueous solutions: The Effect of Hydrolysis and nitrate ion association
Authors: Besbes Rafik , Ouerfelli Noureddine , Abderabba Manef , Lindqvist-Reis Patric , Latrous Habib
Published: September 2013

In recent work, we have deduced that berkelium and gadolinium, which have 4f and 5f with half-filled configurations, also display similar diffusion properties. Results, using self-diffusion coefficients to study thermodynamic properties, show very similar behavior, which is understood given their similarities in charge, ionic size, mobility, conductance, and hydration number. In this paper we undertook a study of Gd3+ as an aid for deducing the thermodynamics properties of the Bk3+ .In first part we compare magnitudes of transport (self-diffusion coefficient) of the trivalent aquo ions of Gd III for two concentrations, C1 = 2 10-4 mol.L-1, C2 = 10-3 mol.L-1 , and in perchlorate and nitrate media . In second part, we studied the variation of D with the mediumâ€™s pH. Self-diffusion coefficients, D, of the trivalent f-elements aqua ions have been determined in an aqueous electrolyte support of Gd(NO3)3 and Nd(ClO4)3 and at a pH=2.5. (HNO3, HClO4 ) and at 25 Â°C using the open-end capillary method (O.E.C.M.).The variation of D versus pH shows three zonesWe changed the NO3- counter ion with ClO4- ,and found that measurements must be carried in perchloric acid medium so as to avoid pairing phenomena. Using association constants between Gd3+ and NO3- , and a hydration constant, we estimated self-diffusion coefficients for Gd(NO3)2+ and Gd(OH)2+ .The results justified our choice of working at pH = 2.5 which constitute an optimum condition to avoid hydrolysis and pairing phenomena. Our results were confirmed by mobility measurements using an electro migration technique.
Selective Release of antiâ€“TB Drugs Complex from Smart Copolymeric Bioactive nanoâ€“carriers
Authors: Arredondo–Penaranda Alejandro , Guerrero–Ramirez Luis Guillermo , Gaitan Maria Dolores Blanco , Mendizabal Eduardo , Katime Issa
Published: September 2013

Smart nanoâ€“copolymeric matrices have been employed to load and release anti tuberculosis (anti â€“TB) drugs combinated complexes of Ethambutol (EMB), Isoniazid (INH), Rifampicin (RMP) and Pyrazinamide (PZA). Copolymeric nanocarriers were synthesized using a microemulsion polymerization method previously reported. These nanocarriers can show selective swellingâ€“collapse response under changes in local environments such a temperature, pH, solvent composition and electrical stimuli. The employ of these kinds of systems permits a controlled and selective delivery and release on specific human tissues. High Performance Liquid Chromatography technique was used to allow the detection of combinated mixtures of different active principles of antiâ€“TB drugs using an acetonitrile mobile phase at 0.5 mL/min of flow rate whit a Spherisorb ODS2, C18 column. The results obtained suggest that the employ of smart nanohydrogels is a novel method in several tuberculosis therapies.
Concentration dependent wetting by aniline-ethanol binary system
Authors: Madhurima Vinjanampaty , Lalnunsiama Jonathan
Published: September 2013

Wetting of five substrates namely glass, indium tin oxide, aluminum oxide, hylam and teflon by aniline-ethanol binary system over the entire concentration range is studied using contact angle measurements. Rapid wetting of the substrates, especially hylam in the aniline rich region is understood in terms of the surface energies of the substrates and the intermolecular interactions between the two moieties. FTIR, dielectric and conformational analysis are used to study the molecular interactions in the binary system.
Perfluoroalkyl Epoxides: Synthesis and Conversion into Ionic Surfactants
Authors: Ayari Abdelhamid , Mekni Henda , Jaoued Najeh Grayaa , Hedhli Ahmed
Published: September 2013

Perfluoroalkylated surfactants having a quaternary ammonium surrounded by three hydroxyl groups as hydrophilic moiety and a perfluoroalkyl chain as tail were obtained by coupling diethanolamine with perfluoroalkylated epoxide followed by quaternisation. The amphiphilic properties of these surfactants were investigated by measuring their surface and interfacial tensions.
Highly diastereoselective synthesis of N-substituted 4-(diethoxyphosphoryl)-pyrrolidines-3-carboxylate starting from tetraethyl methylenediphosphonate
Authors: Ameur Maha , Arfaoui Aicha , Ben Kraiem Jihene , Al-Deyab Salem S. , Amri Hassen
Published: September 2013

Â This paper describes a convenient synthesis of novel series of 3,4-disubstituted pyrrolidines based on the aza-Michael addition of primary amines to 3,4-difunctionalized-1,3-diene followed by an intramolecular cyclization.
Analysis of chemical composition of high viscous oils
Authors: Yashchenko Irina Germanovna , Polishchuk Yury Mikhailovich
Published: September 2013

The spatial distribution of viscous oils which are considered as an important reserve for oil-production in future were studied on base of information from global database on oil physical and chemical properties. Changes in chemical composition of viscous oils in different basins and continents were analyzed as well. It is shown, on average, viscous oils are sulfur-bearing, low paraffin, highly resinous oils with an average content of asphaltenes and low content of the fraction boiling at 200 ï‚°C. Study results of viscous oils peculiarities of Canada, Russia and Venezuela are given. The analysis results can be used to determine the optimal layouts and conditions of oil transportation, to improve the search methods of geochemical exploration, and to solve other problems in the oil chemistry.