Nowadays, short dental implants are being increasingly applied in extremely resorbed posterior regions. The recent studies have indicated that short implants present a similar success rate to conventional implants. It is assumed that short implants can avoid additional surgical morbidity and are less technically demanding. However, high-quality evidence (≥Ib: evidence from at least one randomized controlled trial) on comparing the clinical outcome of short implants and longer implants combined with osteotome sinus floor elevation (OSFE) technique is limited.
The proposed study is designed as a prospective single-center, three-arm parallel group, randomized controlled trial. We plan to enroll 150 patients in need of dental implant treatment in the posterior maxilla. The inclusion criteria include: age ≧18 years, partial edentulism in the posterior maxilla for at least 3 months from tooth loss, residual bone height ranging from 6 to 8 mm, sufficient bone width (≥6 mm) in the edentulous region. The patients will be divided into three groups according to a table of random numbers: group 1: short implants (6 mm) alone; group 2: short implants (8 mm) combined with osteotome sinus floor elevation (OSFE); group 3: standard implants (10 mm) combined with OSFE. The assignment will be concealed from the clinical operators until the beginning of implant surgery. The outcome examiners and patients will be kept blinded to the assignment. Implant survival rates, implant success rates, complications, resonance frequency analysis (RFA) measurements, marginal bone level, treatment time and patient-reported outcome (visual analogue scale for intraoperative discomfort and postoperative pain) will be recorded. Clinical re-evaluations will be performed at 12, 24, 36 and 60 months after crown placement.
The results of the trial will support better decision-making for dental implant treatment in atrophic maxillary ridges. If favorable, the use of short implants may avoid adjunct procedures used for implant insertion, thus reducing operative time, complexity and postoperative discomfort.
Clinicaltrials.gov identifier: NCT02350075 (registered on 17 February 2015).
Dental implants; Short implants; Osteotome sinus floor elevation; Clinical evaluation
The mechanism of how magnetotactic bacteria navigate along magnetic field has been a puzzle. Two main models disagree on whether the magnetotactic behavior results from passive alignment to the magnetic field or active sensing of the magnetic force. Here, we quantitatively studied the swimming patterns of Magnetospirillum magneticum AMB-1 cells to understand the origin of their magnetotaxis behaviors. Single-cell tracking and swimming pattern analysis showed that the cells follow a mixed run/reverse/tumble pattern. The average run time decreased with the angle between the cell’s moving velocity and the external magnetic field. For mutant cells without the methyl-accepting chemotaxis protein (MCP) Amb0994, such dependence disappeared and bacteria failed to align to magnetic field lines. This dysfunction was recovered by complementary amb0994 on plasmid. At high magnetic field (>5mT), all strains with intact magnetosome chains (including the Δamb0994-0995 strain) showed alignment with the external magnetic field. These results suggested that the mechanism for magnetotaxis is magnetic field dependent. Due to the magnetic dipole moment of the cell, the external magnetic field exerts a torque on the cell. In high magnetic fields, this torque is large enough to overcome the random re-orientation of the cell, and the cells align passively with the external magnetic field, much like a compass. In smaller (and biologically more relevant) external fields, the external force alone is not strong enough to align the cell mechanically. However, magnetotactic behaviors persist due to an active sensing mechanism in which the cell senses the torque by Amb0994 and actively regulate the flagella bias accordingly to align its orientation with the external magnetic field. Our results reconciled the two putative models for magnetotaxis and revealed a key molecular component in the underlying magneto-sensing pathway.
Objective. To test the hypothesis that salidroside (SAL) can protect heart from exhaustive exercise-induced injury by enhancing mitochondrial respiratory function and mitochondrial biogenesis key signaling pathway PGC-1α–NRF1/NRF2 in rats. Methods. Male Sprague-Dawley rats were divided into 4 groups: sedentary (C), exhaustive exercise (EE), low-dose SAL (LS), and high-dose SAL (HS). After one-time exhaustive swimming exercise, we measured the changes in cardiomyocyte ultrastructure and cardiac marker enzymes and mitochondrial electron transport system (ETS) complexes activities in situ. We also measured mitochondrial biogenesis master regulator PGC-1α and its downstream transcription factors, NRF1 and NRF2, expression at gene and protein levels. Results. Compared to C group, the EE group showed marked myocardium ultrastructure injury and decrease of mitochondrial respiratory function (P < 0.05) and protein levels of PGC-1α, NRF1, and NRF2 (P < 0.05) but a significant increase of PGC-1α, NRF1, and NRF2 genes levels (P < 0.05); compared to EE group, SAL ameliorated myocardium injury, increased mitochondrial respiratory function (P < 0.05), and elevated both gene and protein levels of PGC-1α, NRF-1, and NRF-2. Conclusion. Salidroside can protect the heart from exhaustive exercise-induced injury. It might act by improving myocardial mitochondrial respiratory function by stimulating the expression of PGC-1α–NRF1/NRF2 pathway.
The classic non-working (NW) heterotopic heart transplant (HTX) model in rodents had been widely used for researches related to immunology, graft rejection, evaluation of immunosuppressive therapies and organ preservation. But unloaded models are considered not suitable for some researches. Accordingly, We have constructed a volume-loaded (VL) model by a new and simple technique.
Thirty male New Zealand White rabbits were randomly divided into two groups, group NW with 14 rabbits and group VL with 16 rabbits, which served as donors and recipients. We created a large and nonrestrictive shunt to provide left heart a sufficient preload. The donor superior vena cave and ascending aorta (AO) were anastomosed to the recipient abdominal aorta (AAO) and inferior vena cava (IVC), respectively.
No animals suffered from paralysis, pneumonia and lethal bleeding. Recipients’ mortality and morbidity were 6.7% (1/15) and 13.3% (2/15), respectively. The cold ischemia time in group VL is slight longer than that in group NW. The maximal aortic velocity (MAV) of donor heart was approximately equivalent to half that of native heart in group VL. Moreover, the similar result was achieved in the parameter of late diastolic mitral inflow velocity between donor heart and native heart in group VL. The echocardiography (ECHO) showed a bidirectional flow in donor SVC of VL model, inflow during diastole and outflow during systole. PET-CT imaging showed the standard uptake value (SUV) of allograft was equal to that of native heart in both groups on the postoperative day 3.
We have developed a new VL model in rabbits, which imitates a native heart hemodynamically while only requiring a minor additional procedure. Surgical technique is simple compared with currently used HTX models. We also developed a standard operating procedure that significantly improved graft and recipient survival rate. This study may be useful for investigations in transplantation in which a working model is required.
Heterotopic heart transplantation (HTX); volume-loaded model (VL model); standard operating procedure
To investigate the effects of CCL21/CCR7 on the proliferation, migration, and invasion of T24 cells and the possible associated mechanisms: expression of MMP-2 and MMP-9, and regulation of BCL-2 and BAX proteins.
T24 cells received corresponding treatments including vehicle control, antibody (20ng/mL CCR7 antibody and 50 ng/ml CCL21), and 50, 100, and 200 ng/ml CCL21. Proliferation was evaluated by MTT assay; cell migration and invasion were assayed using a transwell chamber. Cell apoptosis was induced by Adriamycin (ADM). The rate of cell apoptosis was examined by flow cytometry using annexin V-FITC/PI staining. Western-blot was used to analyze MMP-2 and MMP-9 and BCL-2 and BAX proteins.
CCL21 promoted T24 cell proliferation in concentration-dependent manner with that 200 ng/mL induced the largest amount of proliferation. Significant differences of cell migration were found between CCL21treatment groups and the control group in both the migration and invasion studies (P < 0.001 for all). The expressions of MMP-2 and MMP-9 proteins were significantly increased after CCL21 treatment (p < 0.05 for all). Protein expression of Bcl-21 follows an ascending trend while the expression of Bax follows a descending trend as the concentration of CCL21 increases. No difference was found between the control group and antibody group for all assessments.
CCL21/CCR7 promoted T24 cell proliferation and enhanced its migration and invasion via the increased expression of MMP-2 and MMP-9. CCL21/CCR7 had antiapoptotic activities on T24 cells via regulation of Bcl-2 and Bax proteins. CCL21/CCR7 may promote bladder cancer development and metastasis.
A description is given of new tools to facilitate model building and refinement into electron cryo-microscopy reconstructions.
The recent rapid development of single-particle electron cryo-microscopy (cryo-EM) now allows structures to be solved by this method at resolutions close to 3 Å. Here, a number of tools to facilitate the interpretation of EM reconstructions with stereochemically reasonable all-atom models are described. The BALBES database has been repurposed as a tool for identifying protein folds from density maps. Modifications to Coot, including new Jiggle Fit and morphing tools and improved handling of nucleic acids, enhance its functionality for interpreting EM maps. REFMAC has been modified for optimal fitting of atomic models into EM maps. As external structural information can enhance the reliability of the derived atomic models, stabilize refinement and reduce overfitting, ProSMART has been extended to generate interatomic distance restraints from nucleic acid reference structures, and a new tool, LIBG, has been developed to generate nucleic acid base-pair and parallel-plane restraints. Furthermore, restraint generation has been integrated with visualization and editing in Coot, and these restraints have been applied to both real-space refinement in Coot and reciprocal-space refinement in REFMAC.
model building; refinement; electron cryo-microscopy reconstructions; LIBG
Instituted in major medical programs only within the past decade, the advent of an ‘expanded’ 8-year medical curriculum reflects a major reformation of how physicians are trained in China. Although much remains to be done, including the refinement of associated learning objectives, instructional models, and teaching pedagogies, movement toward a longer, more standardized training framework represents a marked transition for Chinese medical practice. This article highlights the current status and anticipated future of these emerging 8-year medical training programs in modern-day China.
medical education; China; cultivating objective; teaching model
PH5 is a petunia gene that encodes a plasma membrane H+-ATPase and determines the vacuolar pH. The citrate content of fruit cell vacuoles influences citrus organoleptic qualities. Although citrus could have PH5-like homologs that are involved in citrate accumulation, the details are still unknown. In this study, extensive data-mining with the PH5 sequence and PCR amplification confirmed that there are at least eight PH5-like genes (CsPH1-8) in the citrus genome. CsPHs have a molecular mass of approximately 100 kDa, and they have high similarity to PhPH5, AtAHA10 or AtAHA2 (from 64.6 to 80.9%). They contain 13–21 exons and 12–20 introns and were evenly distributed into four subgroups of the P3A-subfamily (CsPH1, CsPH2, and CsPH3 in Group I, CsPH4 and CsPH5 in Group II, CsPH6 in Group IV, and CsPH7 and CsPH8 in Group III together with PhPH5). A transcript analysis showed that CsPH1, 3, and 4 were predominantly expressed in mature leaves, whereas CsPH2 and 7 were predominantly expressed in roots, CsPH5 and 6 were predominantly expressed in flowers, and CsPH8 was predominantly expressed in fruit juice sacs (JS). Moreover, the CsPH transcript profiles differed between orange and pummelo, as well as between high-acid and low-acid cultivars. The low-acid orange “Honganliu” exhibits low transcript levels of CsPH3, CsPH4, CsPH5, and CsPH8, whereas the acid-free pummelo (AFP) has only a low transcript level of CsPH8. In addition, ABA injection increased the citrate content significantly, which was accompanied by the obvious induction of CsPH2, 6, 7, and 8 transcript levels. Taken together, we suggest that CsPH8 seems likely to regulate citrate accumulation in the citrus fruit vacuole.
abscisic acid; citrus; citrate accumulation; fruit development; plasma membrane H+-ATPase
Sucrose synthase (Sus) (EC 18.104.22.168) is a key enzyme for the sugar accumulation that is critical to form fruit quality. In this study, extensive data-mining and PCR amplification confirmed that there are at least six Sus genes (CitSus1-6) in the citrus genome. Gene structure and phylogeny analysis showed an evolutionary consistency with other plant species. The six Sus genes contain 12–15 exons and 11–14 introns and were evenly distributed into the three plant Sus groups (CitSus1 and CitSus2 in the Sus I group, CitSus3 and CitSus6 in the Sus II group, and CitSus4 and CitSus5 in the Sus III group). Transcripts of these six CitSus genes were subsequently examined. For tissues and organs, CitSus1 and 2 were predominantly expressed in fruit juice sacs (JS) whereas CitSus3 and 4 were predominantly expressed in early leaves (immature leaves), and CitSus5 and 6 were predominantly expressed in fruit JS and in mature leaves. During fruit development, CitSus5 transcript increased significantly and CitSus6 transcript decreased significantly in fruit JS. In the fruit segment membrane (SM), the transcript levels of CitSus2 and 5 were markedly higher and the abundant levels of CitSus3 and 6 gradually decreased. Moreover, transcript levels of CitSus1-4 examined were higher and the CitSus5 transcript level was lower in the fruit SM than in fruit JS, while CitSus6 had a similar transcript level in fruit JS and SM. In addition, transcripts of CitSus1-6 responded differently to dehydration in mature leaves or to mild drought stress in fruit JS and SM. Finally, the possible roles of Sus genes in the regulation of sugar accumulation are discussed; however, further study is required.
Single-molecule force spectroscopy with an atomic force microscope has been widely used to study inter- and intramolecular interactions. To obtain data consistent with single molecular events, a well-defined method is critical to limit the number of molecules at the apex of an AFM probe to one or to a few. In this paper, we demonstrate an easy method for single-molecule probe modification by using the Cu-catalyzed alkyne–azide cycloaddition reaction. Excess terminal alkynes were covalently attached to the probe, and a bi-functional molecule containing an azide at one end and a carboxylic acid at the other was dissolved in the reaction solution. By simply contacting the probe and the Cu substrate, controlled carboxylation on the probe apex could be achieved, since the ‘click’ reaction requires the co-exist of alkyne, azide and Cu(I). The finite contact area would result in a highly defined surface functionality of the probe down to single molecule level with high reproducibility.
atomic force microscopy; click reaction; force spectroscopy; single molecule modification
Infection-related complications have been a critical issue for the application of titanium orthopedic implants. The use of Ag nanoparticles offers a potential approach to incorporate antimicrobial properties into the titanium implants. In this work, a novel and simple method was developed for synthesis of Ag (II) oxide deposited TiO2 nanotubes (TiNTs) using electrochemical anodization followed by Ag electroplating processes in the same electrolyte. The quantities of AgO nanoparticles deposited in TiNT were controlled by selecting different electroplating times and voltages. It was shown that AgO nanoparticles were crystalline and distributed throughout the length of the nanotubes. Inductively coupled plasma mass spectrometry tests showed that the quantities of released Ag were less than 7 mg/L after 30 days at 37°C. Antimicrobial assay results show that the AgO-deposited TiNTs can effectively kill the Escherichia coli bacteria. Although the AgO-deposited TiNTs showed some cytotoxicity, it should be controllable by optimization of the electroplating parameters and incorporation of cell growth factor. The results of this study indicated that antimicrobial properties could be added to nanotextured medical implants through a simple and cost effective method.
TiO2 nanotube arrays; anodization; AgO nanoparticles; antimicrobial; cytotoxicity
Mitochondria have specialized ribosomes that have diverged from their bacterial and cytoplasmic counterparts. We have solved the structure of the yeast mitoribosomal large subunit using single-particle electron cryo-microscopy. The resolution of 3.2 Ångstroms enabled a nearly complete atomic model to be built de novo and refined, including 39 proteins, 13 of which are unique to mitochondria, as well as expansion segments of mitoribosomal RNA. The structure reveals a new exit tunnel path and architecture, unique elements of the E site and a putative membrane docking site.
A large number of wearable and implantable electronic medical devices are widely used in clinic and playing an increasingly important role in diagnosis and treatment, but the limited battery capacity restricts their service life and function expansion. Piezoelectric nanogenerators can convert mechanical energy into electrical energy. Our experiment tries to find out if the piezoelectric nanogenerator fixed to the surface of the heart can convert the natural contractions and relaxations of the heart into stable electric energy for electronic medical devices such as pacemakers.
We used Chinese miniature pig and prepared with standard open chest procedure. Then we fixed two opposite edges of the rectangular nanogenerator at the following three positions of the heart respectively to detect the electric voltage output: Position A, right ventricular surface, near the atrioventricular groove, parallel to the long axis of the heart; Position B, right ventricular surface, parallel to the atrioventricular groove; and Position C, left ventricular surface, near cardiac apex, parallel to the left anterior descending branch. Then we selected the place which has the highest voltage output to fix both ends of the nanogenerator and closed the chest of pig. We recorded the voltage output of nanogenerator under closed chest condition (natural condition) and compared the result with open chest condition. Finally we used Dopamine (positive inotropic agents) and Esmolol (negative inotropic agents) respectively to detect the relation between voltage output of nanogenerator and myocardial contractility.
With its both ends fixed on the surface of the heart, the piezoelectric nanogenerator produced stable voltage output from the mechanical contractions of the heart. Piezoelectric nanogenerator which was fixed at Position A produced the highest voltage output (3.1 V), compared with those fixed at Position B or Position C. The voltage is enough for the pacemaker’s operation. The voltage output of piezoelectric nanogenerator at the natural condition (closed chest) was the same as the open chest condition and made a light emitting diode (LED) light continue to shine, which further confirmed its clinical application value. The voltage output of piezoelectric nanogenerator is positively correlated with the myocardial contractile force. The voltage output increased after we used positive inotropic agents and decreased after we used negative inotropic agents.
Piezoelectric nanogenerators can convert the kinetic energy of the heart during the contractions and relaxations of the muscles to electric energy. The output voltage was stable in three positions on the surface of the heart. The highest voltage appeared on the surface of right ventricle, near atrioventricular groove, parallel to the long axis direction of the heart, which can be the potential new energy source for pacemakers. Piezoelectric nanogenerator can be used as cardiac function monitor in the future for its voltage output is positively correlated with myocardial contractile force.
Implantable medical electronic device; wearable medical electronic device; piezoelectric nanogenerator; body mechanical energy; biomechanical energy harvester; new power source
AIM: To screen lymph nodes metastasis associated long noncoding RNAs (lncRNAs) in colorectal cancer through microarray analysis.
METHODS: Metastatic lymph node (MLN), normal lymph node (NLN) and tumor tissues of 3 colorectal cancer (CRC) patients were collected during the operation and validated by pathological examinations. RNAs were extracted from MLN, NLN, and cancer tissues separately. RNA quantity and quality were measured with a NanoDrop ND-1000 spectrophotometer and RNA integrity was assessed by standard denaturing agarose electrophoresis. Agilent Feature Extraction Software (Version 22.214.171.124) was used to analyze acquired array images. Four differently expressed lncRNAs were confirmed by quantitative real-time polymerase chain reaction (qRT-PCR) in 26 subsets of MLN, NLN, and tumor tissues.
RESULTS: Of 33045 lncRNAs, 1133 were differentially expressed in MLN compared with NLN, of which 260 were up-regulated and 873 down-regulated (≥ 2 fold-change). Five hundred and forty-five lncRNAs were differentially expressed in MLN compared with tumor tissues, of which 460 were up-regulated and 85 down-regulated (≥ 2 fold-change). Compared with NLN and cancer tissues, 14 lncRNAs were specifically up-regulated and 5 specifically down-regulated in MLN. AK307796, ENST00000425785, and AK021444 were confirmed to be specifically up-regulated in MLN and ENST00000465846 specifically down-regulated in MLN by qRT-PCR in 26 CRC patients.
CONCLUSION: The specifically expressed lncRNAs in MLN may exert a partial or key role in the progress of lymph nodes metastasis of CRC.
Long noncoding RNAs; Colorectal cancer; Lymph nodes metastasis; Quantitative real-time polymerase chain reaction; MicroRNA
The PDB_REDO pipeline aims to improve macromolecular structures by optimizing the crystallographic refinement parameters and performing partial model building. Here, algorithms are presented that allowed a web-server implementation of PDB_REDO, and the first user results are discussed.
The refinement and validation of a crystallographic structure model is the last step before the coordinates and the associated data are submitted to the Protein Data Bank (PDB). The success of the refinement procedure is typically assessed by validating the models against geometrical criteria and the diffraction data, and is an important step in ensuring the quality of the PDB public archive [Read et al. (2011 ▶), Structure, 19, 1395–1412]. The PDB_REDO procedure aims for ‘constructive validation’, aspiring to consistent and optimal refinement parameterization and pro-active model rebuilding, not only correcting errors but striving for optimal interpretation of the electron density. A web server for PDB_REDO has been implemented, allowing thorough, consistent and fully automated optimization of the refinement procedure in REFMAC and partial model rebuilding. The goal of the web server is to help practicing crystallographers to improve their model prior to submission to the PDB. For this, additional steps were implemented in the PDB_REDO pipeline, both in the refinement procedure, e.g. testing of resolution limits and k-fold cross-validation for small test sets, and as new validation criteria, e.g. the density-fit metrics implemented in EDSTATS and ligand validation as implemented in YASARA. Innovative ways to present the refinement and validation results to the user are also described, which together with auto-generated Coot scripts can guide users to subsequent model inspection and improvement. It is demonstrated that using the server can lead to substantial improvement of structure models before they are submitted to the PDB.
PDB_REDO; validation; model optimization
Bacteria of the genus Photobacterium thrive worldwide in oceans and show substantially varied lifestyles, including free-living, commensal, pathogenic, symbiotic, and piezophilic. Here, we present the genome sequence of a luminous, piezophilic Photobacterium phosphoreum strain, ANT-2200, isolated from a water column at 2,200 m depth in the Mediterranean Sea. It is the first genomic sequence of the P. phosphoreum group. An analysis of the sequence provides insight into the adaptation of bacteria to the deep-sea habitat.
Intricate coordinated mechanisms that govern the synchrony of hair growth and melanin synthesis remain largely unclear. These two events can be uncoupled in prematurely gray hair, probably due to oxidative insults that lead to the death of oxidative stress-sensitive melanocytes. In this study, we examined the gene expression profiles of middle (bulge) and lower (hair bulb) segments that had been micro-dissected from unpigmented and from normally pigmented hair follicles from the same donors using quantitative real-time RT-PCR (qPCR) arrays. We found a significant down-regulation of melanogenesis-related genes (TYR, TYRP1, MITF, PAX3, POMC) in unpigmented hair bulbs and of marker genes typical for melanocyte precursor cells (PAX3, SOX10, DCT) in unpigmented mid-segments compared with their pigmented analogues. qPCR, western blotting and spin trapping assays revealed that catalase protein expression and hydroxyl radical scavenging activities are strongly repressed in unpigmented hair follicles. These data provide the first clear evidence that compromised antioxidant activity in gray hair follicles simultaneously affects mature hair bulb melanocytes and their immature precursor cells in the bulge region.
The purpose of this study was to evaluate reconstruction of the medial patellofemoral ligament (MPFL) using the double-bundle anatomical or single-bundle isometric procedure with respect to the patients’ clinical outcomes.
In this retrospective study, we evaluated the clinical outcome of double-bundle anatomical versus single-bundle isometric reconstruction of the MPFL for patellar dislocation patients. Sixty-three patients were included in this study from August 2004 to January 2008. From August 2004 to September 2006, MPFL reconstruction using a single-bundle isometric technique was performed in 21 patients (26 knees). Since October 2006, the double-bundle anatomical reconstruction of the MPFL has been used as the routine surgical procedure. It was performed in 37 patients (44 knees). Fifty-eight patients (70 knees) could be followed up. According to the different techniques, we divided the patients into two groups: group D with double-bundle anatomical reconstruction (37 patients) and group S with single-bundle isometric reconstruction (21 patients). Clinical evaluation consisted of the number with a patellar re-dislocation, patellar apprehension sign, Kujala score, subjective questionnaire score, the patella lateral shift rate and patellar tilt angle measured by cross-sectional CT scan.
According to the Kujala score and the subjective questionnaire score, the outcome of the double-bundle group was better than the outcome of the single-bundle group especially in the long-term. Patellar re-dislocation occurred in three patients in the group S, while no re-dislocation occurred in the group D. In total, 26.9 % of group S was considered to have patellar instability, compared to 4.54 % of the group D. After operation, the patellar tilt angle (PTA) and the patella lateral shift rate (PLSR) were restored to the normal range, with statistical significance (P < 0.05) compared to the preoperative state.
Single- and double-bundle reconstruction of the MPFL can both effectively restore patella stability and improve knee function. However, outcomes in the follow-up period showed that the double-bundle surgery procedure was much better than in single-bundle surgery.
In the title compound, [Fe(C5H5)(C9H6ClN2)], the two cyclopentadienyl rings are almost parallel, subtending a dihedral angle of 3.01 (5)°. The dihedral angle between the substituted cyclopentadienyl ring and the pyrimidinyl ring is 12.02 (1)°. The conformation of the two cyclopentadienyl rings in the ferrocenyl moiety is eclipsed.
The endophytic strain Zong1 isolated from root nodules of the legume Sophora alopecuroides was characterized by conducting physiological and biochemical tests employing gfp-marking, observing their plant growth promoting characteristics (PGPC) and detecting plant growth parameters of inoculation assays under greenhouse conditions. Results showed that strain Zong1 had an effective growth at 28 ºC after placed at 4–60 ºC for 15 min, had a wide range pH tolerance of 6.0–11.0 and salt tolerance up to 5% of NaCl. Zong1 was resistant to the following antibiotics (μg/mL): Phosphonomycin (100), Penicillin (100) and Ampicillin (100). It could grow in the medium supplemented with 1.2 mmol/L Cu, 0.1% (w/v) methylene blue and 0.1–0.2% (w/v) methyl red, respectively. Zong1 is closely related to Pseudomonas chlororaphis based on analysis the sequence of 16S rRNA gene. Its expression of the gfp gene indicated that strain Zong1 may colonize in root or root nodules and verified by microscopic observation. Furthermore, co-inoculation with Zong1 and SQ1 (Mesorhizobium sp.) showed significant effects compared to single inoculation for the following PGPC parameters: siderophore production, phosphate solubilization, organic acid production, IAA production and antifungal activity in vitro. These results suggest strains P. chlororaphi Zong1 and Mesorhizobium sp. SQ1 have better synergistic or addictive effect. It was noteworthy that each growth index of co-inoculated Zong1+SQ1 in growth assays under greenhouse conditions is higher than those of single inoculation, and showed a significant difference (p < 0.05) when compared to a negative control. Therefore, as an endophyte P. chlororaphis Zong1 may play important roles as a potential plant-growth promoting agent.
PGPC; endophyte; the gpf-marker; colonization; co-inoculation
Novel large, rod-shaped magnetotactic bacteria (MTB) were discovered in intertidal sediments of the Yellow Sea, China. They biomineralized more than 300 rectangular magnetite magnetosomes per cell. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that they are affiliated with the Alphaproteobacteria and may represent a new genus of MTB.
Acute treatment of stroke with HDAC inhibitors has been shown to reduce ischemic cell damage; however, it is unclear whether delayed treatment with HDAC inhibitors will contribute to the brain repair and plasticity. In the present study, we investigated the effects of delayed treatment of stroke with a pan HDAC inhibitor, valproic acid (VPA), on white matter injury and neurogenesis during stroke recovery. Administration of VPA at a dose of 100 mg/kg for 7 days starting 24 hours after middle cerebral artery occlusion (MCAo) in rats significantly improved neurological outcome measured 7 to 28 days post-MCAo. In addition, the VPA treatment significantly increased oligodendrocyte survival and newly generated oligodendrocytes, which was associated with elevation of myelinated axonal density in the ischemic boundary 28 days after MCAo. VPA treatment also increased the expression of glutamate transporter 1 (GLT1) in the ischemic boundary after stroke, and increased acetylated histone H4 expression in neuroblasts and the number of new neurons in striatal ischemic boundary region. This study provides new evidence that the delayed VPA treatment enhances white matter repair and neurogenesis in ischemic brain, which may contribute to improved functional outcome.
Valproic acid; oligodendrocyte; axon; neural progenitor cells; subventricular zone (SVZ); stroke
To determine the pathogenesis of a patient born with congenital heart defects, who had appeared normal in prenatal screening.
In routine prenatal screening, G-banding was performed to analyse the karyotypes of the family and fluorescence in situ hybridization was used to investigate the 22q11.2 deletion in the fetus. After birth, the child was found to be suffering from heart defects by transthoracic echocardiography. In the following study, sequencing was used to search for potential mutations in pivotal genes. SNP-array was employed for fine mapping of the aberrant region and quantitative real-time PCR was used to confirm the results. Furthermore, other patients with a similar phenotype were screened for the same genetic variations. To compare with a control, these variations were also assessed in the general population.
The child and his mother each had a region that was deleted in the beta-defensin repeats, which are usually duplicated in the general population. Besides, the child carried a SOX7-gene duplication. While this duplication was not detected in his mother, it was found in two other patients with cardiac defects who also had the similar deletion in the beta-defensin repeats.
The congenital heart defects of the child were probably caused by a SOX7-gene duplication, which may be a consequence of the partial haplotype of beta-defensin regions at 8p23.1. To our knowledge, this is the first congenital heart defect case found to have the haplotype of beta-defensin and the duplication of SOX7.
Enterohaemorrhagic Escherichia coli (EHEC) O157:H7 is a major cause of zoonotic food- and water-borne intestinal infections worldwide with clinical consequences ranging from mild diarrhoea to hemolytic uraemic syndrome. The genome of EHEC O157:H7 contains many regions of unique DNA that are referred to as O islands including the Shiga toxin prophages and pathogenicity islands encoding key virulence factors. However many of these O islands are of unknown function. In this study, genetic analysis was conducted on OI-172 which is a 44,434 bp genomic island with 27 open reading frames. Comparative genome analysis showed that O1-72 is a composite island with progressive gain of genes since O157:H7 evolved from its ancestral O55:H7. A partial OI-172 island was also found in 2 unrelated E. coli strains and 2 Salmonella strains. OI-172 encodes several putative helicases, one of which (Z5898) is a putative DEAH box RNA helicase. To investigate the function of Z5898, a deletion mutant (EDL933ΔZ5898) was constructed in the O157:H7 strain EDL933. Comparative proteomic analysis of the mutant with the wild-type EDL933 found that flagellin was down-regulated in the Z5898 mutant. Motility assay showed that EDL933ΔZ5898 migrated slower than the wild-type EDL933 and electron microscopy found no surface flagella. Quantitative reverse transcription PCR revealed that the fliC expression of EDL933ΔZ5898 was significantly lower while the expression of its upstream regulator gene, fliA, was not affected. Using a fliA and a fliC promoter – green fluorescent protein fusion contruct, Z5898 was found to affect only the fliC promoter activity. Therefore, Z5898 regulates the flagella based motility by exerting its effect on fliC. We conclude that OI-172 is a motility associated O island and hereby name it the MAO island.
Corky split vein caused by boron (B) deficiency in ‘Newhall’ Navel Orange was studied in the present research. The boron-deficient citrus exhibited a symptom of corky split vein in mature leaves. Morphologic and anatomical surveys at four representative phases of corky split veins showed that the symptom was the result of vascular hypertrophy. Digital gene expression (DGE) analysis was performed based on the Illumina HiSeq™ 2000 platform, which was applied to analyze the gene expression profilings of corky split veins at four morphologic phases. Over 5.3 million clean reads per library were successfully mapped to the reference database and more than 22897 mapped genes per library were simultaneously obtained. Analysis of the differentially expressed genes (DEGs) revealed that the expressions of genes associated with cytokinin signal transduction, cell division, vascular development, lignin biosynthesis and photosynthesis in corky split veins were all affected. The expressions of WOL and ARR12 involved in the cytokinin signal transduction pathway were up-regulated at 1st phase of corky split vein development. Furthermore, the expressions of some cell cycle genes, CYCs and CDKB, and vascular development genes, WOX4 and VND7, were up-regulated at the following 2nd and 3rd phases. These findings indicated that the cytokinin signal transduction pathway may play a role in initiating symptom observed in our study.