A collection of 36 Clostridium botulinum type E strains was examined by pulsed-field gel electrophoresis (PFGE) and Southern hybridization with probes targeted to botE and orfX1 in the neurotoxin gene cluster. Three strains were found to contain neurotoxin subtype E1 gene clusters in large plasmids of about 146 kb in size.
The relationship between suicidality and major depression is complex. Socio- demography, clinical features, comorbidity, clinical symptoms, and stressful life events are important factors influencing suicide in major depression, but these are not well defined. Thus, the aim of the present study was to assess the associations between the above-mentioned factors and suicide ideation, suicide plan, and suicide attempt in 6008 Han Chinese women with recurrent major depression (MD). Patients with any suicidality had significantly more MD symptoms, a significantly greater number of stressful life events, a positive family history of MD, a greater number of episodes, a significant experience of melancholia, and earlier age of onset. Comorbidity with dysthymia, generalized anxiety disorder (GAD), social phobia, and animal phobia was seen in suicidal patients. The present findings indicate that specific factors act to increase the likelihood of suicide in MD. Our results may help improve the clinical assessment of suicide risk in depressed patients, especially for women.
Wdpcp, a protein required for both planar cell polarity and ciliogenesis, regulates cell polarity and alignment via direct modulation of the actin cytoskeleton.
Planar cell polarity (PCP) regulates cell alignment required for collective cell movement during embryonic development. This requires PCP/PCP effector proteins, some of which also play essential roles in ciliogenesis, highlighting the long-standing question of the role of the cilium in PCP. Wdpcp, a PCP effector, was recently shown to regulate both ciliogenesis and collective cell movement, but the underlying mechanism is unknown. Here we show Wdpcp can regulate PCP by direct modulation of the actin cytoskeleton. These studies were made possible by recovery of a Wdpcp mutant mouse model. Wdpcp-deficient mice exhibit phenotypes reminiscent of Bardet–Biedl/Meckel–Gruber ciliopathy syndromes, including cardiac outflow tract and cochlea defects associated with PCP perturbation. We observed Wdpcp is localized to the transition zone, and in Wdpcp-deficient cells, Sept2, Nphp1, and Mks1 were lost from the transition zone, indicating Wdpcp is required for recruitment of proteins essential for ciliogenesis. Wdpcp is also found in the cytoplasm, where it is localized in the actin cytoskeleton and in focal adhesions. Wdpcp interacts with Sept2 and is colocalized with Sept2 in actin filaments, but in Wdpcp-deficient cells, Sept2 was lost from the actin cytoskeleton, suggesting Wdpcp is required for Sept2 recruitment to actin filaments. Significantly, organization of the actin filaments and focal contacts were markedly changed in Wdpcp-deficient cells. This was associated with decreased membrane ruffling, failure to establish cell polarity, and loss of directional cell migration. These results suggest the PCP defects in Wdpcp mutants are not caused by loss of cilia, but by direct disruption of the actin cytoskeleton. Consistent with this, Wdpcp mutant cochlea has normal kinocilia and yet exhibits PCP defects. Together, these findings provide the first evidence, to our knowledge, that a PCP component required for ciliogenesis can directly modulate the actin cytoskeleton to regulate cell polarity and directional cell migration.
Cilia are microscopic cell surface hair-like protrusions that can act as antennae to mediate cell signaling. Mutations disrupting ciliogenesis can cause many developmental anomalies associated with syndromes known as “ciliopathies.” Some developmental defects, such as limb polydactyly, arise from disruption of cilia-transduced sonic hedgehog signaling, while other defects, such as aberrant patterning of hair cells in the inner ear, arise from disrupted Wnt signaling resulting in modulation of planar cell polarity (PCP)—a process whereby cells are polarized and aligned. While ciliopathy phenotypes would suggest that cilia are involved in modulating PCP, the mechanistic link between cilia and PCP has been elusive. Our study using a mouse model carrying a mutation in Wdpcp, a gene required for both ciliogenesis and PCP, suggest that Wdpcp modulation of PCP involves interactions with the actin cytoskeleton separate from its function in ciliogenesis. We observe Wdpcp localization in cilia, where it is required for recruitment of proteins essential for ciliogenesis. Wdpcp interacts with Sept2, and is also found in actin filaments, where it regulates actin dynamics essential for PCP. Together, these findings show that PCP regulation by Wdpcp is distinct from its function in ciliogenesis and involves direct modulation of the actin cytoskeleton.
SNAP25, an essential component of the soluble NSF (N-ethylmaleimide-sensitive factor) attachment protein receptor (SNARE) complex that mediates exocytosis, is not considered to play a role in endocytosis, which couples to exocytosis by retrieving a similar amount of exocytosed vesicles. By knocking down SNAP25 and imaging slow endocytosis at a conventional synapse, the rat cultured hippocampal synapse, we found that SNAP25 is involved in slow, clathrin-dependent endocytosis. With similar techniques, we found that not only SNAP25, but also synaptobrevin is involved in slow endocytosis. These results provide the first evidence showing the dual role of SNAP25 and synaptobrevin in both exocytosis and slow endocytosis at conventional synapses. Such a dual role may contribute to mediate the coupling between exocytosis and clathrin-dependent endocytosis at conventional synapses, a mechanism critical for the maintenance of synaptic transmission and the normal structure of nerve terminals.
MicroRNAs play critical roles in various biological and metabolic processes. The function of miRNAs has been widely studied in model plants such as Arabidopsis and rice. However, the number of identified miRNAs and related miRNA targets in peach (Prunus persica) is limited. To understand further the relationship between miRNAs and their target genes during tissue development in peach, a small RNA library and three degradome libraries were constructed from three tissues for deep sequencing. We identified 117 conserved miRNAs and 186 novel miRNA candidates in peach by deep sequencing and 19 conserved miRNAs and 13 novel miRNAs were further evaluated for their expression by RT-qPCR. The number of gene targets that were identified for 26 conserved miRNA families and 38 novel miRNA candidates, were 172 and 87, respectively. Some of the identified miRNA targets were abundantly represented as conserved miRNA targets in plant. However, some of them were first identified and showed important roles in peach development. Our study provides information concerning the regulatory network of miRNAs in peach and advances our understanding of miRNA functions during tissue development.
Parallel conductance (electric current flow through surrounding tissue) is an important determinant of accurate measurements of arterial lumen diameter, using the conductance method. The present study is focused on the role of non-uniform geometrical/electrical configurations of surrounding tissue, which are a primary source of electric current leakage. Computational models were constructed to simulate the conductance catheter measurement with two different excitation electrodes spacings (i.e. 12 and 20 mm for coronary and peripheral sizing, respectively) for different vessel–tissue configurations: (i) blood vessel fully embedded in muscle tissue, (ii) blood vessel superficially embedded in muscle tissue, and (iii) blood vessel superficially embedded in muscle tissue with fat covering half of the arterial vessel (anterior portion). The simulations suggest that the parallel conductance and accuracy of measurement is dependent on the inhomogeneous/anisotropic configuration of surrounding tissue, including the asymmetric dimension and anisotropy in electrical conductivity of surrounding tissue. Specifically, the measurement was shown to be accurate as long as the vessel was superficial, regardless of the considerable total surrounding tissue dimension for coronary or peripheral arteries. Moreover, it was shown that the unfavourable impact of parallel conductance on the accuracy of conductance catheter measurement is decreased by the combination of a lower transverse electrical conductivity of surrounding muscle tissue, a smaller electrode spacing and a larger lumen diameter. The present findings confirm that the conductance catheter technique provides an accurate platform for sizing of clinically relevant (i.e. superficial and diseased) arteries.
parallel conductance; impedance catheter; asymmetric surrounding tissue; anisotropic electrical conductivity
Objective: This study deals with the effect of phosphoric acid etching and conditioning on enamel micro-tensile bond strengths (μTBSs) of conventional and resin-modified glass ionomer cements (GICs/RMGICs). Methods: Forty-eight bovine incisors were prepared into rectangular blocks. Highly-polished labial enamel surfaces were either acid-etched, conditioned with liquids of cements, or not further treated (control). Subsequently, two matching pre-treated enamel surfaces were cemented together with one of four cements [two GICs: Fuji I (GC), Ketac Cem Easymix (3M ESPE); two RMGICs: Fuji Plus (GC), RelyX Luting (3M ESPE)] in preparation for μTBS tests. Pre-treated enamel surfaces and cement-enamel interfaces were analyzed by scanning electron microscopy (SEM). Results: Phosphoric acid etching significantly increased the enamel μTBS of GICs/RMGICs. Conditioning with the liquids of the cements produced significantly weaker or equivalent enamel μTBS compared to the control. Regardless of etching, RMGICs yielded stronger enamel μTBS than GICs. A visible hybrid layer was found at certain enamel-cement interfaces of the etched enamels. Conclusions: Phosphoric acid etching significantly increased the enamel μTBSs of GICs/RMGICs. Phosphoric acid etching should be recommended to etch the enamel margins before the cementation of the prostheses such as inlays and onlays, using GICs/RMGICs to improve the bond strengths. RMGICs provided stronger enamel bond strength than GICs and conditioning did not increase enamel bond strength.
Glass ionomer cements; Surface treatments; Bovine enamels; Scanning electron microscopy (SEM); Micro-tensile bond strengths
Drought is a major threat to agriculture production worldwide. Mitogen-activated protein kinases (MAPKs) play a pivotal role in sensing and converting stress signals into appropriate responses so that plants can adapt and survive. To examine the function of MAPKs in the drought tolerance of tomato plants, we silenced the SpMPK1, SpMPK2, and SpMPK3 genes in wild-type plants using the virus-induced gene silencing (VIGS) method. The results indicate that silencing the individual genes or co-silencing SpMPK1, SpMPK2, and SpMPK3 reduced the drought tolerance of tomato plants by varying degrees. Co-silencing SpMPK1 and SpMPK2 impaired abscisic acid (ABA)-induced and hydrogen peroxide (H2O2)-induced stomatal closure and enhanced ABA-induced H2O2 production. Similar results were observed when silencing SpMPK3 alone, but not when SpMPK1 and SpMPK2 were individually silenced. These data suggest that the functions of SpMPK1 and SpMPK2 are redundant, and they overlap with that of SpMPK3 in drought stress signaling pathways. In addition, we found that SpMPK3 may regulate H2O2 levels by mediating the expression of CAT1. Hence, SpMPK1, SpMPK2, and SpMPK3 may play crucial roles in enhancing tomato plants’ drought tolerance by influencing stomatal activity and H2O2 production via the ABA-H2O2 pathway.
Solanum pimpinellifolium; protein kinase; stomata; drought tolerance; virus-induced gene silencing (VIGS)
Transcription factors (TFs) and miRNAs are essential for the regulation of gene expression; however, the global view of human gene regulatory networks remains poorly understood. For example, how is the expression of so many genes regulated by limited cohorts of regulators and how are genes differentially expressed in different tissues despite the genetic code being the same in all tissues?
We analyzed the network properties of housekeeping and tissue-specific genes in gene regulatory networks from seven human tissues. Our results show that different classes of genes behave quite differently in these networks. Tissue-specific miRNAs show a higher average target number compared with non-tissue specific miRNAs, which indicates that tissue-specific miRNAs tend to regulate different sets of targets. Tissue-specific TFs exhibit higher in-degree, out-degree, cluster coefficient and betweenness values, indicating that they occupy central positions in the regulatory network and that they transfer genetic information from upstream genes to downstream genes more quickly than other TFs. Housekeeping TFs tend to have higher cluster coefficients compared with other genes that are neither housekeeping nor tissue specific, indicating that housekeeping TFs tend to regulate their targets synergistically. Several topological properties of disease-associated miRNAs and genes were found to be significantly different from those of non-disease-associated miRNAs and genes.
Tissue-specific miRNAs, TFs and disease genes have particular topological properties within the transcriptional regulatory networks of the seven human tissues examined. The tendency of tissue-specific miRNAs to regulate different sets of genes shows that a particular tissue-specific miRNA and its target gene set may form a regulatory module to execute particular functions in the process of tissue differentiation. The regulatory patterns of tissue-specific TFs reflect their vital role in regulatory networks and their importance to biological functions in their respective tissues. The topological differences between disease and non-disease genes may aid the discovery of new disease genes or drug targets. Determining the network properties of these regulatory factors will help define the basic principles of human gene regulation and the molecular mechanisms of disease.
Regulatory networks; Tissue-specific genes; Housekeeping genes; Cluster coefficient
Clinical epidemiological studies suggested a link between fetal growth conditions and later coronary heart disease (CHD) in adult life. However, no such studies have been conducted in a Chinese population.
We investigated the association between various birth characteristics and CHD occurrence in a Chinese cohort.
Retrospective cohort study.
Peking Union Medical College Hospital, Beijing, China.
A total of 2,033 subjects who were born at Peking Union Medical College Hospital between 1921 and 1954.
Neonatal birth-weight, placental weight, length from crown to heel, head circumference, and biparietal and occipitofrontal diameters were routinely recorded at the time of birth. All participants were followed up between May 2002 and April 2004 for the occurrence of CHD.
CHD was identified in 135 patients. The occurrence of CHD was inversely related to birth sizes, such as birth-weight, head circumference, placental weight (P < 0.05), but was not significantly related to birth length or ponderal index (birth-weight/birth length3). After multivariable logistic regression, the ratio of birth-weight to birth length was an independent predictor of CHD along with two other variables: obesity and age.
This was a single-center retrospective study.
In China low birth size or birth disproportion, which is suggestive of fetal growth retardation, has an effect on CHD occurrence during adulthood. This suggests that environmental factors operate in both the prenatal and postnatal periods with regard to the development of CHD.
Birth size; coronary artery disease; fetal growth retardation; risk factors
Thymosin beta 4 (Tβ4) is a peptide with 43 amino acids that is critical for repair and remodeling tissues on the skin, eye, heart, and neural system following injury. To fully realize its utility as a treatment for disease caused by injury, the authors constructed a cost-effective novel Tβ4 dimer and demonstrated that it was better able to accelerate tissue repair than native Tβ4.
A prokaryotic vector harboring two complete Tβ4 genes with a short linker was constructed and expressed in Escherichia coli. A pilot-scale fermentation (10 L) was performed to produce engineered bacteria and the Tβ4 dimer was purified by one-step hydrophobic interaction chromatography. The activities of the Tβ4 dimer to promote endothelial cell proliferation, migration, and sprouting were assessed by tetramethylbenzidine (methylthiazol tetrazolium), trans-well, scratch, and tube formation assays. The ability to accelerate dermal healing was assessed on rats.
After fermentation, the Tβ4 dimer accounted for about 30% of all the bacteria proteins. The purity of the Tβ4 dimer reached 98% after hydrophobic interaction chromatography purification. An average of 562.4 mg/L Tβ4 dimer was acquired using a 10 L fermenter. In each assay, the dimeric Tβ4 exhibited enhanced activities compared with native Tβ4. Notably, the ability of the dimeric Tβ4 to promote cell migration was almost two times higher than that of Tβ4. The rate of dermal healing in the dimeric Tβ4-treated rats was approximately 1 day faster than with native Tβ4-treated rats.
The dimeric Tβ4 exhibited enhanced activity on wound healing than native Tβ4, and the purification process was simple and cost-effective. This data could be of significant benefit for the high pain and morbidity associated with chronic wounds disease. A better strategy to develop Tβ4 as a treatment for other diseases caused by injuries such as heart attack, neurotrophic keratitis, and multiple sclerosis was also described.
thymosin beta 4; dimer; wound healing; tissue repair; peptide; genetic engineering
The content of icaritin and genistein in herba is very low, preparation with relatively large quantities is an important issue for extensive pharmacological studies.
This study focuses on preparing and enzymic hydrolysis of flavonoid glycosides /β-cyclodextrin inclusion complex to increase the hydrolysis rate.
Materials and Methods:
The physical property of newly prepared inclusion complex was tested by differential scanning calorimetry (DSC). The conditions of enzymatic hydrolysis were optimized for the bioconversion of flavonoid glycosides /β-cyclodextrin inclusion complex by mono-factor experimental design. The experiments are using the icariin and genistein as the model drugs.
The solubility of icariin and genistein were increased almost 17 times from 29.2 μg/ml to 513.5 μg/ml at 60°C and 28 times from 7.78 μg/ml to 221.46 μg/ml at 50°C, respectively, demonstrating that the inclusion complex could significantly increase the solubility of flavonoid glycosides. Under the optimal conditions, the reaction time of icariin and genistin decreased by 68% and 145%, when compared with that without β-CD inclusion. By using this enzymatic condition, 473 mg icaritin (with the purity of 99.34%) and 567 mg genistein(with the purity of 99.46%), which was finally determined by melt point, ESI-MS, UV, IR, 1H NMR and 13C NMR, was obtained eventually by transforming the inclusion complex(contains 1.0 g substrates).
This study can clearly indicate a new attempt to improve the speed of enzyme-hydrolysis of poorly water-soluble flavonoid glycosides and find a more superior condition which is used to prepare icaritin and genistein.
Cellulase; enzymatic hydrolysis; flavonoid glycosides; snailase; β-CD inclusion complex
Essential proteins are indispensable for cell survive. Identifying essential proteins is very important for improving our understanding the way of a cell working. There are various types of features related to the essentiality of proteins. Many methods have been proposed to combine some of them to predict essential proteins. However, it is still a big challenge for designing an effective method to predict them by integrating different features, and explaining how these selected features decide the essentiality of protein. Gene expression programming (GEP) is a learning algorithm and what it learns specifically is about relationships between variables in sets of data and then builds models to explain these relationships.
In this work, we propose a GEP-based method to predict essential protein by combing some biological features and topological features. We carry out experiments on S. cerevisiae data. The experimental results show that the our method achieves better prediction performance than those methods using individual features. Moreover, our method outperforms some machine learning methods and performs as well as a method which is obtained by combining the outputs of eight machine learning methods.
The accuracy of predicting essential proteins can been improved by using GEP method to combine some topological features and biological features.
Non-propagating evanescent fields play an important role in the development of nano-photonic devices. While detecting the evanescent fields in far-field can be accomplished by coupling it to the propagating waves, in practice they are measured in the presence of unwanted propagating background components. It leads to a poor signal-to-noise ratio and thus to errors in quantitative analysis of the local evanescent fields. Here we report on a plasmonic near-field scanning optical microscopy (p-NSOM) technique that incorporates a nanofocusing probe for adiabatic focusing of propagating surface plasmon polaritons at the probe apex, and for enhanced coupling of evanescent waves to the far-field. In addition, a harmonic demodulation technique is employed to suppress the contribution of the background. Our experimental results show strong evidence of background free near-field imaging using the new p-NSOM technique. Furthermore, we present measurements of surface plasmon cavity modes, and quantify their contributing sources using an analytical model.
Angiotensin-converting enzyme 2 (ACE2), a monocarboxypeptidase which metabolizes angiotensin II (Ang II) to generate Ang-(1–7), has been shown to prevent cardiac hypertrophy and injury but the mechanism remains elusive. Irbesartan has the dual actions of angiotensin receptor blockade and peroxisome proliferator-activated receptor-γ (PPARγ) activation. We hypothesized that irbesartan would exert its protective effects on ACE2 deficiency-mediated myocardial fibrosis and cardiac injury via the PPARγ signaling.
10-week-old ACE2 knockout (ACE2KO; Ace2-/y) mice received daily with irbesartan (50 mg/kg) or saline for 2 weeks. The wild-type mice (Ace2+/y) were used to the normal controls. We examined changes in myocardial ultrastructure, fibrosis-related genes and pathological signaling by real-time PCR gene array, Western blotting, Masson trichrome staining and transmission electron microscope analyses, respectively.
Compared with the Ace2+/y mice, cardiac expression of PPARα and PPARγ were reduced in Ace2-/y mice and the myocardial collagen volume fraction (CVF) and expression of fibrosis-related genes were increased, including transforming growth factor-β1 (TGFβ1), connective tissue growth factor (CTGF), collagen I and collagen III. Moreover, ACE2 deficiency triggered cardiac hypertrophy, increased myocardial fibrosis and adverse ultrastructure injury in ACE2KO hearts with higher levels of atrial natriuretic factor (ANF) and phosphorylated extracellular signal-regulated kinase 1/2 (ERK1/2), without affecting cardiac systolic function. Intriguingly, treatment with irbesartan significantly reversed ACE2 deficiency-mediated pathological hypertrophy and myocardial fibrosis in Ace2-/y mice linked with enhancement of plasma Ang-(1–7) level and downregulation of AT1 receptor in heart. Consistent with attenuation of myocardial fibrosis and ultrastructure injury, the myocardial CVF and levels of ANF, TGFβ1, CTGF, collagen I, collagen III and phosphorylated ERK1/2 were lower, and expression of PPARγ was higher in ACE2KO mice in response to irbesartan treatment, without affecting cardiac expression of PPARα, PPARδ, β-myosin heavy chain, TGFβ2 and fibronectin.
We conclude that irbesartan prevents ACE2 deficiency-mediated pathological hypertrophy and myocardial fibrosis in ACE2 mutant mice via activation of the PPARγ signaling and suppression of the TGFβ−CTGF−ERK signaling, resulting in attenuation of myocardial injury. Drugs targeting ACE2 and PPARγ represent potential candidates to prevent and treat myocardial injury and related cardiac disorders.
Angiotensin-converting enzyme 2; Irbesartan; Peroxisome proliferator-activated receptor-γ; Connective tissue growth factor; Myocardial injury
While most Japanese apricot (Prunus mume Sieb. et Zucc.) cultivars display typical S-RNase-based gametophytic self-incompatibility, some self-compatible (SC) cultivars have also been identified. In this study, we confirmed SC of ‘Zaohong’ through replicated self-pollination tests. Cross-pollination tests showed that SC of ‘Zaohong’ was caused by a loss of pollen function, so we determined that the S-genotype of ‘Zaohong’ was S2S15. Sequence analysis of the S-haplotypes of ‘Zaohong’ showed no mutations which were likely to alter gene function. Furthermore, expression analysis based on RT-PCR of S-locus genes revealed no differences at the transcript level when compared with ‘Xiyeqing’, a self-incompatible cultivar with the same S haplotypes. In addition, except for S-locus genes, a new type of F-box gene encoding a previously uncharacterised protein with high sequence similarity (61.03–64.65 %) to Prunus SFB genes was identified. Putative structural regions of PmF-box genes have been described, corresponding to regions in PmSFB alleles, but with some sequence variations. These results suggest that SC in ‘Zaohong’ occurs in pollen, and that other factors outside the S-locus, including PmF-box genes, might be associated with the loss of function of pollen S genes.
Japanese apricot; Self-compatibility (compatible) (SC); Self-incompatibility (incompatible) (SI); S-RNase; SFB; PmF-box
Since individualized therapy becomes more and more important in the treatment of rectal cancer, an accurate and effective approach should be established in the clinical settings to help physicians to make their decisions. Circulating tumor cells (CTCs), originated from either primary or metastatic cancer, could provide important information for diagnosis and monitoring of cancer. However, the implication and development of CTCs are limited due to the extreme rarity of these tumor cells. In this study we fabricated a simple and high-performance microfluidic device, which exploited numerous filtered microchannels in it to enrich the large-sized target tumor cells from whole blood. A very high CTC capture efficiency (average recovery rate: 94%) was obtained in this device at the optimum flow rate of 0.5 mL/h and channel height of 5 µm. Additionally, we used this device for detecting CTCs in 60 patients with rectal cancer. The CTC counts of rectal cancer patients were significantly higher than those in healthy subjects. Furthermore, the CTC counts detected by this device were significantly higher than those by EpCAM bead-based method for rectal cancer patients with various stage. Especially, for localized rectal cancer patients, the positive rates of samples with more than 3 CTCs per 5 mL blood by use of microdevice vs. EpCAM-based ones were 100% vs. 47%, respectively. Thus, this device provides a new and effective tool for accurate identification and measurement of CTCs in patients with rectal cancer, and has broad potential in clinical practice.
The widespread use of clopidogrel alone or in combination with aspirin may result in gastrointestinal mucosal injury, clinically represented as recurrent ulceration and bleeding complications. Our recent work suggested that clopidogrel significantly induced human gastric epithelial cell (GES-1) apoptosis and disrupted gastric mucosal barrier, and that a p38 MAPK inhibitor could attenuate such injury. However, their exact mechanisms are largely unknown.
The GES-1 cells were used as a model system, the effects of clopidogrel on the whole gene expression profile were evaluated by human gene expression microarray and gene ontology analysis, changes of the mRNA and protein expression were determined by real-time PCR and Western blot analysis, and cell viability and apoptosis were measured by MTT assay and flow cytometry analysis, respectively.
Gene microarray analysis identified 79 genes that were differentially expressed (P<0.05 and fold-change >3) when cells were treated with or without clopidogrel. Gene ontology analysis revealed that response to stress and cell apoptosis dysfunction were ranked in the top 10 cellular events being affected, and that the major components of endoplasmic reticulum stress-mediated apoptosis pathway – CHOP and TRIB3– were up-regulated in a concentration- and time-dependent manner when cells were treated with clopidogrel. Pathway analysis demonstrated that multiple MAPK kinases were phosphorylated in clopidogrel-treated GES-1 cells, but that only SB-203580 (a p38-specific MAPK inhibitor) attenuated cell apoptosis and CHOP over-expression, both of which were induced by clopidogrel.
Increased endoplasmic reticulum stress response is involved in clopidogrel-induced gastric mucosal injury, acting through p38 MAPK activation.
Manganese-oxidizing bacteria in the aquatic environment have been comprehensively investigated. However, little information is available about the distribution and biogeochemical significance of these bacteria in terrestrial soil environments. In this study, stratified soils were initially examined to investigate the community structure and diversity of manganese-oxidizing bacteria. Total 344 culturable bacterial isolates from all substrata exhibited Mn(II)-oxidizing activities at the range of 1 µM to 240 µM of the equivalent MnO2. The high Mn(II)-oxidizing isolates (>50 mM MnO2) were identified as the species of phyla Actinobacteria, Firmicutes and Proteobacteria. Seven novel Mn(II)-oxidizing bacterial genera (species), namely, Escherichia, Agromyces, Cellulomonas, Cupriavidus, Microbacterium, Ralstonia, and Variovorax, were revealed via comparative phylogenetic analysis. Moreover, an increase in the diversity of soil bacterial community was observed after the combined enrichment of Mn(II) and carbon-rich complex. The phylogenetic classification of the enriched bacteria represented by predominant denaturing gradient gel electrophoresis bands, was apparently similar to culturable Mn(II)-oxidizing bacteria. The experiments were further undertaken to investigate the properties of the Mn oxide aggregates formed by the bacterial isolates with high Mn(II)-oxidizing activity. Results showed that these bacteria were closely encrusted with their Mn oxides and formed regular microspherical aggregates under prolonged Mn(II) and carbon-rich medium enrichment for three weeks. The biotic oxidation of Mn(II) to Mn(III/IV) by these isolates was confirmed by kinetic examinations. X-ray diffraction assays showed the characteristic peaks of several Mn oxides and rhodochrosite from these aggregates. Leucoberbelin blue tests also verified the Mn(II)-oxidizing activity of these aggregates. These results demonstrated that Mn oxides were formed at certain amounts under the enrichment conditions, along with the formation of rhodochrosite in such aggregates. Therefore, this study provides insights into the structure and diversity of soil-borne bacterial communities in Mn(II)-oxidizing habitats and supports the contribution of soil-borne Mn(II)-oxidizing bacteria to Mn oxide mineralization in soils.
Crystal structure analyses for biological macromolecules without known structural relatives entail solving the crystallographic phase problem. Typical de novo phase evaluations depend on incorporating heavier atoms than those found natively; most commonly, multi- or single-wavelength anomalous diffraction (MAD or SAD) experiments exploit selenomethionyl proteins. Here we realize routine structure determination using intrinsic anomalous scattering from native macromolecules. We devised robust procedures for enhancing signal-to-noise in the slight anomalous scattering from generic native structures by combining data measured from multiple crystals at lower-than-usual x-ray energy. Using this multi-crystal SAD method (5–13 equivalent crystals), we determined structures at modest resolution (2.8Å-2.3Å) for native proteins varying in size (127–1148 unique residues) and number of sulfur sites (3–28). With no requirement for heavy-atom incorporation, such experiments provide an attractive alternative to selenomethionyl SAD experiments.
AIM: To evaluate the clinical value of diffusion-weighted magnetic resonance imaging (DW-MRI) in predicting the response of rectal cancer to neoadjuvant chemoradiation.
METHODS: This prospective study was approved by our institutional review board, and informed consent was obtained from each patient. Fifteen patients (median age 56 years) with locally advanced rectal cancer were treated in our hospital from June 2006 to December 2007. All patients were stage IIIB-C according to the results of MRI and endorectal ultrasound examinations. All patients underwent pelvic irradiation with 45 Gy/25 fx per 35 days. The concurrent chemotherapy regimen consisted of capecitabine 625 mg/m2, bid (Monday-Friday), and oxaliplatin 50 mg/m2, weekly. The patients underwent surgery 5-8 wk after the completion of neoadjuvant therapy. T downstaging was defined as the downstaging of the tumor from cT3 to ypT0-2 or from cT4 to ypT0-3. Good regression was defined as TRG 3-4, and poor regression was defined as TRG 0-2. Diffusion-weighted magnetic resonance images were obtained prior to and weekly during the course of neoadjuvant chemoradiation, and the apparent diffusion coefficient (ADC) values were calculated from the acquired tumor images.
RESULTS: Comparison with the mean pretreatment tumor ADC revealed an increase in the mean tumor ADC during the course of neoadjuvant chemoradiation, especially at the 2nd week (P = 0.004). We found a strong negative correlation between the mean pretreatment tumor ADC and tumor regression after neoadjuvant chemoradiation (P = 0.021). In the T downstage and tumor regression groups, we found a significant increase in the mean ADC at the 2nd week of neoadjuvant therapy (P = 0.011; 0.004).
CONCLUSION: DW-MRI might be a valuable clinical tool to help predict or assess the response of rectal cancer to neoadjuvant chemoradiation at an early timepoint.
Locally advanced rectal cancer; Neoadjuvant chemoradiation; Diffusion-weighted magnetic resonance imaging; Apparent diffusion coefficient
Hormones are closely associated with dormancy in deciduous fruit trees, and gibberellins (GAs) are known to be particularly important. In this study, we observed that GA4 treatment led to earlier bud break in Japanese apricot. To understand better the promoting effect of GA4 on the dormancy release of Japanese apricot flower buds, proteomic and transcriptomic approaches were used to analyse the mechanisms of dormancy release following GA4 treatment, based on two-dimensional gel electrophoresis (2-DE) and digital gene expression (DGE) profiling, respectively. More than 600 highly reproducible protein spots (P<0.05) were detected and, following GA4 treatment, 38 protein spots showed more than a 2-fold difference in expression, and 32 protein spots were confidently identified according to the databases. Compared with water treatment, many proteins that were associated with energy metabolism and oxidation–reduction showed significant changes after GA4 treatment, which might promote dormancy release. We observed that genes at the mRNA level associated with energy metabolism and oxidation–reduction also played an important role in this process. Analysis of the functions of the identified proteins and genes and the related metabolic pathways would provide a comprehensive proteomic and transcriptomic view of the coordination of dormancy release after GA4 treatment in Japanese apricot flower buds.
2-DE; DGE; dormancy; GA4; Japanese apricot; proteomics; transcriptomics.
Coronary arteries bring blood flow to the heart muscle. Understanding the developmental program of the coronary arteries provides insights into the treatment of coronary artery diseases. Multiple sources have been described as contributing to coronary arteries including the proepicardium, sinus venosus (SV), and endocardium. However, the developmental origins of coronary vessels are still under intense study. We have produced a new genetic tool for studying coronary development, an AplnCreER mouse line, which expresses an inducible Cre recombinase specifically in developing coronary vessels. Quantitative analysis of coronary development and timed induction of AplnCreER fate tracing showed that the progenies of subepicardial endothelial cells (ECs) both invade the compact myocardium to form coronary arteries and remain on the surface to produce veins. We found that these subepicardial ECs are the major sources of intramyocardial coronary vessels in the developing heart. In vitro explant assays indicate that the majority of these subepicardial ECs arise from endocardium of the SV and atrium, but not from ventricular endocardium. Clonal analysis of Apln-positive cells indicates that a single subepicardial EC contributes equally to both coronary arteries and veins. Collectively, these data suggested that subepicardial ECs are the major source of intramyocardial coronary arteries in the ventricle wall, and that coronary arteries and veins have a common origin in the developing heart.
coronary artery; origin; development; subepicardial endothelial cell; angiogenesis
Osteogenesis imperfecta (OI) type V is an autosomal-dominant disease characterized by calcification of the forearm interosseous membrane, radial head dislocation, a subphyseal metaphyseal radiodense line, and hyperplastic callus formation. The causative mutation, c.-14C>T in the 5'-untranslated region of IFITM5, was recently discovered to be involved in this disease. However, in spite of the little genotypic variability, considerable phenotypic variability has been recognized in two cohorts of patients, the majority of whom were Caucasians. Using exome sequencing, we identified the same heterozygous mutation in four Chinese families with OI type V. This study confirms the molecular cause of OI type V and describes the phenotype of Chinese patients with this disorder. In conclusion, the phenotype of Chinese patients was generally similar to that of Caucasian patients.
We propose a quantum key distribution scheme that combines a biased basis choice with the decoy-state method. In this scheme, Alice sends all signal states in the Z basis and decoy states in the X and Z basis with certain probabilities, and Bob measures received pulses with optimal basis choice. This scheme simplifies the system and reduces the random number consumption. From the simulation result taking into account of statistical fluctuations, we find that in a typical experimental setup, the proposed scheme can increase the key rate by at least 45% comparing to the standard decoy-state scheme. In the postprocessing, we also apply a rigorous method to upper bound the phase error rate of the single-photon components of signal states.