Changes of mitochondrial respiratory function during odontogenic differentiation of rat dental papilla cells

Dental papilla cells (DPCs) belong to precursor cells differentiating to odontoblasts and play an important role in dentin formation and reproduction. This study aimed to explore the changes and and involvement of mitochondrial respiratory function during odontogenic differentiation. Primary DPCs were obtained from first molar dental papilla of neonatal rats and cultured in odontogenic medium for 7, 14, 21 days. DPCs, which expressed mesenchymal surface markers CD29, CD44 and CD90, had the capacity for self-renewal and multipotent differentiation. Odontoblastic induction increased mineralized matrix formation in a time-dependent manner, which was accompanied by elevated alkaline phosphatase (ALP), dentin sialophosphoprotein and dentin matrix protein 1 expression at mRNA and protein levels. Notably, odontogenic medium led to an increase in adenosine-5'-triphosphate content and mitochondrial membrane potential, whereas a decrease in intercellular reactive oxygen species production and NAD⁺/NADH ratio. Furthermore, odontogenic differentiation was significantly suppressed by treatment with rotenone, an inhibitor of mitochondrial respiratory chain. These results demonstrate that enhanced mitochondrial function is crucial for odontogenic differentiation of DPCs.

Efficient electro-optic modulation in low-loss graphene-plasmonic slot waveguides

Surface plasmon polaritons enable light concentration within subwavelength regions, opening thereby new avenues for miniaturizing the device and strengthening light-matter interactions. Here we realize efficient electro-optic modulation in low-loss plasmonic waveguides with the aid of graphene, and the devices are fully integrated in the silicon-on-insulator platform. By advantageously exploiting low-loss plasmonic slot-waveguide modes, which weakly leak into a substrate while featuring strong fields within the two-layer-graphene covered slots in metals, we successfully achieve a tunability of 0.13 dB μm^-1 for our fabricated graphene-plasmonic waveguide devices with extremely low insertion loss, which outperforms previously reported graphene-plasmonic devices. Our results highlight the potential of graphene plasmonic leaky-mode hybrid waveguides to realize active ultra-compact devices for optoelectronic applications.

[Clinical efficacy of clear aligners in treating bimaxillary protrusion]

Objective: To evaluate the efficiency of clear aligners in treating bimaxillary protrusion patients with first premolar extractions. Methods: Eleven patients with bimaxillary protrusion were selected in this study. All of them were treated by using clear aligners with four first premolar extractions and need maximal anchorage. Cephalometric analysis was carried out before and after treatment. Results: Cephalometric analysis results showed that significant changes in teeth and profile could be detected after clear aligner treatment and no change could be found in skeletal pattern. Upper and lower anterior teeth were retracted. The control of anterior torque and posterior anchorage were effective. The soft tissue analysis showed that position of upper and lower lip was significantly changed which improve the profile of patients. After treatment, the distance of U1 to NA and L1 to NB reduced by (5.19±4.12) mm and (4.53±1.20) mm, respectively. The differences were statistically significant (P<0.01). Conclusions: Bimaxillary protrusion patients who needed premolar extractions and maximal anchorage could be treated with clear aligners.

Radiation reduction of minimally invasive transforaminal lumbar interbody fusion with localisation system in overweight patients: practical technique

AIMS

Minimally invasive transforaminal lumbar interbody fusion (MITLIF) has been well validated in overweight and obese patients who are consequently subject to a higher radiation exposure. This prospective multicentre study aimed to investigate the efficacy of a novel lumbar localisation system for MITLIF in overweight patients.

PATIENTS AND METHODS

The initial study group consisted of 175 patients. After excluding 49 patients for various reasons, 126 patients were divided into two groups. Those in Group A were treated using the localisation system while those in Group B were treated by conventional means. The primary outcomes were the effective radiation dosage to the surgeon and the exposure time.

RESULTS

There were 62 patients in Group A and 64 in Group B. The mean effective dosage was 0.0217 mSv (standard deviation (sd) 0.0079) in Group A and 0.0383 mSv (sd 0.0104) in Group B (p < 0.001). The mean fluoroscopy exposure time was 26.42 seconds (sd 5.91) in Group A and 40.67 seconds (sd 8.18) in Group B (p < 0.001). The operating time was 175.56 minutes (sd 32.23) and 206.08 minutes (sd 30.15) (p < 0.001), respectively. The mean pre-operative localisation time was 4.73 minutes (sd 0.84) in Group A and 7.03 minutes (sd 1.51) in Group B (p < 0.001). The mean screw placement time was 47.37 minutes (sd 10.43) in Group A and 67.86 minutes (sd 14.15) in Group B (p < 0.001). The pedicle screw violation rate was 0.35% (one out of 283) in Group A and 2.79% (eight out of 287) in Group B (p = 0.020).

CONCLUSION

The study shows that the localisation system can effectively reduce radiation exposure, exposure time, operating time, pre-operative localisation time, and screw placement time in overweight patients undergoing MITLIF. Cite this article: Bone Joint J 2017;99-B:944-50.

Association of long non-coding RNA H19 and microRNA-21 expression with the biological features and prognosis of non-small cell lung cancer

In recent years, long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) have been shown to play important roles in tumor biological function. The aim of this study was to investigate the diagnostic and prognostic value of lncRNA H19 and miR-21 expression in non-small-cell lung cancer (NSCLC). H19 and miR-21 expression was measured in tumor tissues and corresponding non-tumor lung tissues from 200 patients by quantitative reverse transcription polymerase chain reaction. Moreover, the in vitro and in vivo effects of H19 knock out in A549 cells were investigated. Expression of both H19 and miR-21 was significantly higher in lung tissues from patients with NSCLC than in normal lung tissues. Increased expression of H19 and miR-21 was positively correlated with advanced tumor-node-metastasis stage and tumor size. miR-21 expression was highest in stage I and II NSCLC, whereas H19 expression was highest in stage III and IV NSCLC. Knockout of H19 significantly inhibited NSCLC cell proliferation both in vitro and in vivo. The results show that H19 may mainly contributes to the progression of NSCLC, and its expression levels can reflect the invasive and metastatic status to some extent. miR-21 expression more likely plays an important role in early stage NSCLC. Moreover, H19 and miR-21 interact in the regulation of NSCLC, and with greater expression of both H19 and miR-21, overall survival decreased. The combination of H19 and miR-21 may have diagnostic value in NSCLC and represent a target for new NSCLC treatments.

[Initial study of transthoracic echocardiography guided three-dimensional printing on the application of assessment of structural heart disease]

Objective: To investigate the feasibility and diagnostic value of preoperative transthoracic echocardiography guided three dimensional printing model (TTE Guided 3DPM) on the assessment of structural heart disease (SHD). Methods: From February 2016 to October 2016, 44 patients underwent cardiac surgery in Tianjin Chest Hospital, forty-four patients were assessed preoperatively using TTE Guided 3DPM, including 25 males and 19 females, aged 3-75 years, with an average of (44±22) years. compared to conventional three dimensional transthoracic echocardiography (3D-TTE), and took direct intraoperative findings as "Golden Standard" simultaneously. There are twelve patients with SHD, including four cases with mitral prolapse, two cases with partial endocardial cushion defect, two cases with secondary atrial septal defect, two cases with rheumatic mitral stenosis, one case with tetralogy of Fallot, one case with ventricular septal defect (VSD), thirty-two patients without SHD were designed as negative control. Results: The sensitivity and specificity of TTE Guided 3DPM were greater than or equal to 3D-TTE, P value of McNemar test of 3D-TTE was greater than 0.05, the difference was not statistically significant, kappa=0.745, P<0.01, indicated that the results of 3DTTE and the gold standard were generally consistent.P value of McNemar test of TTE Guided 3DPM was greater than 0.05, the difference was not statistically significant, kappa=0.955, P<0.01, indicated that the results of TTE Guided 3DPM and gold standards were consistent. Compared with 3D-TTE and TTE Guided 3DPM, P value was greater than 0.05, the difference was not statistically significant, kappa=0.879, P<0.01, indicated that the results of 3D-TTE and TTE Guided 3DPM were consistent. TTE Guided 3DPM displayed the three-dimensional structure of SHD cardiac lesions clearly, which were consistent with intraoperative findings. Conclusion: TTE Guided 3DPM provides essential information for the preoperative evaluation and decision of SHD.

Ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry and tandem mass spectrometry for peptide de novo amino acid sequencing for a seven-protein mixture by paired single-residue transposed Lys-N and Lys-C digestion

RATIONALE

Bottom-up tandem mass spectrometry (MS/MS) is regularly used in proteomics to identify proteins from a sequence database. De novo sequencing is also available for sequencing peptides with relatively short sequence lengths. We recently showed that paired Lys-C and Lys-N proteases produce peptides of identical mass and similar retention time, but different tandem mass spectra. Such parallel experiments provide complementary information, and allow for up to 100% MS/MS sequence coverage.

METHODS

Here, we report digestion by paired Lys-C and Lys-N proteases of a seven-protein mixture: human hemoglobin alpha, bovine carbonic anhydrase 2, horse skeletal muscle myoglobin, hen egg white lysozyme, bovine pancreatic ribonuclease, bovine rhodanese, and bovine serum albumin, followed by reversed-phase nanoflow liquid chromatography, collision-induced dissociation, and 14.5 T Fourier transform ion cyclotron resonance mass spectrometry.

RESULTS

Matched pairs of product peptide ions of equal precursor mass and similar retention times from each digestion are compared, leveraging single-residue transposed information with independent interferences to confidently identify fragment ion types, residues, and peptides. Selected pairs of product ion mass spectra for de novo sequenced protein segments from each member of the mixture are presented.

CONCLUSIONS

Pairs of the transposed product ions as well as complementary information from the parallel experiments allow for both high MS/MS coverage for long peptide sequences and high confidence in the amino acid identification. Moreover, the parallel experiments in the de novo sequencing reduce false-positive matches of product ions from the single-residue transposed peptides from the same segment, and thereby further improve the confidence in protein identification. Copyright © 2016 John Wiley & Sons, Ltd.

Transcatheter heart valve crimping and the protecting effects of a polyester cuff

INTRODUCTION

Prior to deployment, the percutaneous heart valves must be crimped and loaded into sheaths of diameters that can be as low as 6mm for a 23mm diameter valve. However, as the valve leaflets are fragile, any damage caused during this crimping process may contribute to reducing its long-term durability in vivo.

MATERIAL AND METHOD

Bovine pericardium percutaneous valves were manufactured as follows. The leaflets were sutured on a nitinol frame. A polyester cuff fabric served as a buffer between the pericardium and the stent. Two valves were crimped and one valve was used as control. The valves were examined in gross observation and micro-CT scan and then the leaflets were processed for histology and analyzed in scanning electron microscopy, light microscopy and transmission electron microscopy.

RESULT

Crimping of the valves resulted in the increase thickness of the leaflets and there was no evidence of additional delamination. The heavy prints of the stents were irregularly distributed on the outflow surface in the crimped devices and were shallow and did not penetrate throughout the thickness of the leaflets. However, the wavy microscopy of collagen fiber bundles was well preserved. They were found to remain individualized without any agglutination as shown by the regular banding appearance.

CONCLUSION

Crimping of self-deployable valves per se caused only minor damages to the leaflets. However, the procedure could be refined in order to minimize areas of high pressure and swelling of the tissue that can be accompanied with flow surface disruption and increase of the hydraulic conductance. The incorporation of a polyester buffer serves to prevent the deleterious effects that may be caused if the pericardium tissue were in direct contact with the nitinol stent.