[Establishment of a 3D printing system for bone tissue engineering scaffold fabrication and the evaluation of its controllability over macro and micro structure precision]

OBJECTIVE

To establish a 3D printing system for bone tissue engineering scaffold fabrication based on the principle of fused deposition modeling, and to evaluate the controllability over macro and micro structure precision of polylactide (PLA) and polycaprolactone (PCL) scaffolds.

METHODS

The system was composed of the elements mixture-I bioprinter and its supporting slicing software which generated printing control code in the G code file format. With a diameter of 0.3 mm, the nozzle of the bioprinter was controlled by a triaxial stepper motor and extruded melting material. In this study, a 10 mm×10 mm×2 mm cuboid CAD model was designed in the image ware software and saved as STL file. The file was imported into the slicing software and the internal structure was designed in a pattern of cuboid pore uniform distribution, with a layer thickness of 0.2 mm. Then the data were exported as Gcode file and ready for printing. Both polylactic acid (PLA) and polycaprolactone (PCL) filaments were used to print the cuboid parts and each material was printed 10 times repeatedly. After natural cooling, the PLA and PCL scaffolds were removed from the platform and the macro dimensions of each one were measured using a vernier caliper. Three scaffolds of each material were randomly selected and scanned by a 3D measurement laser microscope. Measurements of thediameter of struts and the size of pores both in the interlayer overlapping area and non-interlayer overlapping area were taken.

RESULTS

The pores in the printed PLA and PCL scaffolds were regular and interconnected. The printed PLA scaffolds were 9.950 (0.020) mm long, 9.950 (0.003) mm wide and 1.970 (0.023) mm high, while the PCL scaffolds were 9.845 (0.025) mm long, 9.845 (0.045) mm wide and 1.950 (0.043) mm high. The struts of both the PLA and PCL parts became wider inthe interlayer overlapping area, and the former was more obvious. The difference between the designed size and the printed size was greatest in the pore size of the PLA scaffolds in interlayer overlapping area [(274.09 ± 8.35) μm)], which was 26.91 μm. However, it satisfied the requirements for research application.

CONCLUSION

The self-established 3D printing system for bone tissue engineering scaffold can be used to print PLA and PCL porous scaffolds. The controllability of this system over macro and micro structure can meet the precision requirements for research application.

Pharmacokinetics of sanguinarine, chelerythrine, and their metabolites in broiler chickens following oral and intravenous administration

Sanguinarine (SA) and chelerythrine (CHE) are the main active components of the phytogenic livestock feed additive, Sangrovit®. However, little information is available on the pharmacokinetics of Sangrovit® in poultry. The goal of this work was to study the pharmacokinetics of SA, CHE, and their metabolites, dihydrosanguinarine (DHSA) and dihydrochelerythrine (DHCHE), in 10 healthy female broiler chickens following oral (p.o.) administration of Sangrovit® and intravenous (i.v.) administration of a mixture of SA and CHE. The plasma samples were processed using two different simple protein precipitation methods because the parent drugs and metabolites are stable under different pH conditions. The absorption and metabolism of SA following p.o. administration were fast, with half-life (t_1/2 ) values of 1.05 ± 0.18 hr and 0.83 ± 0.10 hr for SA and DHSA, respectively. The maximum concentration (C_max ) of DHSA (2.49 ± 1.4 μg/L) was higher that of SA (1.89 ± 0.8 μg/L). The area under the concentration vs. time curve (AUC) values for SA and DHSA were 9.92 ± 5.4 and 6.08 ± 3.49 ng/ml hr, respectively. Following i.v. administration, the clearance (CL) of SA was 6.79 ± 0.63 (L·h^-1 ·kg^-1 ) with a t_1/2 of 0.34 ± 0.13 hr. The AUC values for DHSA and DHCHE were 7.48 ± 1.05 and 0.52 ± 0.09 (ng/ml hr), respectively. These data suggested that Sangrovit® had low absorption and bioavailability in broiler chickens. The work reported here provides useful information on the pharmacokinetic behavior of Sangrovit® after p.o. and i.v. administration in broiler chickens, which is important for the evaluation of its use in poultry.

[The application of computer-assisted design in the reduction of long bone fractures with Taylor spatial frame]

Objective: To evaluate the effect of computer-assisted design based on three-dimensional reconstruction technique on the reduction accuracy of tibial and fibular fractures with Taylor external fixation. Methods: A retrospective review was conducted on the clinical data of 69 patients who had tibia and fibula fractures treated with Taylor external fixation in department of orthopedic trauma of Tianjin Hospital from January 2016 to January 2018 to compare the residual deformity after fracture reduction between computer-assisted design method (experimental group) and the standard measurement method (control group). The frontal and lateral tibia and fibula X-ray of all the affected limbs were taken. In experimental group, all the patients took bilateral tibial CT tomography, and then DICOM format documents were input into the Mimics 17.1 software and got three-dimensional models of targeted bone and external fixation ring. After that the visual image matching was performed between external fixation ring three-dimensional reconstruction model and the standard model and also between the affected limb and the contralateral limb. Then the reduction trajectory plan of bone broken end and the position of external fixation ring were obtained. The STL files were input to Solid Works software and got the length of six rods to adjust the Taylor external fixation. In control group, the films were measured by Coreldraw X7 X-ray measurement software and the parameters were input in Taylor Spatial Frame system software. And then six calibrated threaded rods were adjusted according to the prescription of the software. Finally, all the patients took the X-ray films again to evaluate the degree of residual displacement. Skew distributional data are indicated with M(Q_R), and method of non-parameter was used to analyze variances between groups. Results: All patients had better fracture reduction and achieved functional reset criteria. In the control group, the amount of displacement and angle residual aberration (improvement) in the frontal and lateral radiographs were 0.50(2.30)mm(90%), 0.00(0.85)mm(100%)and 0.00°(1.50°)(100%), 0.00°(0.00°)(100%), respectively. In the control group, the amount of displacement and angle residual aberration (improvement) in the frontal and lateral radiographs were 1.40(3.28)mm(69%), 2.15(4.27)mm(46%)and 1.15°(1.85°)(73%), 0.80°(2.10°)(67%). The positive and lateral angles and lateral displacements in the two groups were significantly different(P<0.05), but there was no statistically significant difference in positive displacement (P=0.099). Conclusion: Both computer-assisted design method and the standard measurement method have satisfactory reduction effect, but computer-assisted design can accurately correct fracture deformity, which is good for fracture healing and functional recovery of affected limb.

Multi-functional spintronic devices based on boron- or aluminum-doped silicene nanoribbons

Zigzag silicene nanoribbons (ZSiNRs) in the ferromagnetic edge ordering have a metallic behavior, which limits their applications in spintronics. Here a robustly half-metallic property is achieved by the boron substitution doping at the edge of ZSiNRs. When the impurity atom is replaced by the aluminum atom, the doped ZSiNRs possess a spin semiconducting property. Its band gap is suppressed with the increase of ribbon's width, and a pure thermal spin current is achieved by modulating ribbon's width. Moreover, a negative differential thermoelectric resistance in the thermal charge current appears as the temperature gradient increases, which originates from the fact that the spin-up and spin-down thermal charge currents have diverse increasing rates at different temperature gradient regions. Our results put forward a promising route to design multi-functional spintronic devices which may be applied in future low-power-consumption technologies.

[Application of digital design of orthodontic-prosthodontic multidisciplinary treatment plan in esthetic rehabilitation of anterior teeth]

OBJECTIVE

To develop a digital workflow of orthodontic-prosthodontic multidisciplinary treatment plan which can be applied in complicated anterior teeth esthetic rehabilitation, in order to enhance the efficiency of communication between dentists and patients, and improve the predictability of treatment outcome.

METHODS

Twenty patients with the potential needs of orthodontic-prosthodontic multidisciplinary treatment to solve their complicated esthetic problems in anterior teeth were recruited in this study. Digital models of patients' both dental arches and soft tissues were captured using intra oral scanner. Direct prosthodontic (DP) treatment plan and orthodontic-prosthodontic (OP) treatment plan were carried out for each patient. For DP treatment plans, digital wax-up models were directly designed on original digital models using prosthodontic design system. For OP treatment plans, virtual-setups were performed using orthodontic analyze system according to orthodontic and esthetic criteria and imported to prosthodontic design system to finalize the digital wax-up models. These two treatment plans were shown to the patients and demonstrated elaborately. Each patient rated two treatment plans using visual analogue scales and the medians of scores of two treatment plans were analyzed using signed Wilcoxon test. Having taken into consideration various related factors, including time, costs of treatment, each patient chose a specific treatment plan. For the patients chose DP treatment plans, digital wax-up models were exported and printed into resin diagnostic models which would be utilized in the prosthodontic treatment process. For the patients chose OP treatment plans, virtual-setups were used to fabricate aligners or indirect bonding templates and digital wax-up models were also exported and printed into resin diagnostic models for prosthodontic treatment after orthodontic treatment completed.

RESULTS

The medians of scores of DP treatment plan and OP treatment plan were calculated and analyzed by IBM SPSS 20. The median of scores of DP treatment plan was 8.4, the minimum value was 6.9 and the maximum value was 9.3. The median of scores of OP treatment plan was 9.0, the minimum value was 7.9 and the maximum value was 9.6. The median of scores of OP was significantly higher than that of DP (Z=-3.23, P<0.01). Finally, 12 patients chose OP treatment plans and 8 patients chose DP treatment plans.

CONCLUSION

For cases with complex esthetic problems in anterior teeth, a digital workflow can demonstrate final treatment outcome and help patients make suitable treatment decisions. In our study, the orthodontic-prosthodontic multidisciplinary treatment plan is feasible which can provide predictions of treatment outcome and improve esthetic outcome with patients' satisfaction.

Proteomics analysis of faecal proteins in the tick Haemaphysalis flava

BACKGROUND

Ticks and tick-borne diseases are of major public health concern. Currently, development of vaccines against ticks is considered crucial for their control. A critical step in this process is the screening of viable antigens. Faeces are byproducts of digestion and blood meal utilization, and partly reflect the vitality and vector potential of ticks. However, an integrated analysis of proteins in tick faeces is lacking. The present study explored the protein components in the faeces of the tick Haemaphysalis flava, by liquid chromatography-tandem mass spectrometry (LC/MS-MS) to identify potential protein antigens for vaccine development against ticks.

METHODS

Faeces from adult H. flava engorged females were collected. Proteins were extracted from faeces, and the trypsin-digested peptides were analyzed by LC/MS-MS. High confidence proteins were identified based on unique peptides revealed by MS. Potential faecal protein genes, as well as their sources, were also characterized by searching previous transcriptome datasets from the salivary glands and midgut of H. flava.

RESULTS

In total, 21 were recognized with confidence. Amongst these, 18 were of likely tick origin, while three proteins (serum albumin, haemoglobin α and β subunits) were likely from hosts. Seventeen unigenes corresponding to these proteins were retrieved by searching our previous H. flava salivary glands and midgut transcriptomic datasets. Some proteins were reported to prevent blood clotting, play a role in immunity and antibiosis, and formation of musculature. The functions of the remaining proteins are unknown.

CONCLUSIONS

Identifying antigens for tick vaccine development is feasible by analyzing the faecal proteome as well as the transcriptomes of salivary glands and midguts. The vast number of proteins detected in tick faeces highlights the complexity of blood digestion in ticks, a field that needs more investigation.

Identification of gelsemine metabolites in rat liver S9 by high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry

RATIONALE

Gelsemine has been extensively studied because of its anti-tumor, immunomodulatory, insecticidal itching and other significant effects. However, limited information on the pharmacokinetics and metabolism of gelsemine has been reported. Therefore, the purpose of the present study was to investigate the in vitro metabolism of gelsemine in rat liver S9 by using rapid and accurate high-performance liquid chromatography/ quadrupole-time-of-flight mass spectrometry (HPLC/QqTOF-MS).

METHODS

The incubation mixture was processed with 15% trichloroacetic acid. Multiple scans of gelsemine metabolites and accurate mass measurements were automatically performed simultaneously through data-dependent acquisition in only 30 min. The structural elucidations of these metabolites were performed by comparing their changes in accurate molecular masses and product ions with those of the parent drug.

RESULTS

Five metabolites of gelsemine were identified in rat liver S9. Of these, four metabolites of gelsemine were identified for the first time. The present results showed that the metabolic pathways of gelsemine are oxidation, demethylation, and dehydrogenation in rat liver S9.

CONCLUSIONS

In this study, metabolites of gelsemine in liver S9 were identified and elucidated firstly using the HPLC/QqTOF-MS method. The proposed metabolic pathways of gelsemine in liver S9 will provide a basis for further studies of the in vivo metabolism of gelsemine in animals and humans.

A Prospective Investigation into the Epidemiology of In-Hospital Cardiopulmonary Resuscitation Using the International Utstein Reporting Style

Introduction

The Utstein template has been used to guide the assessment and study of cardiopulmonary resuscitation (CPR) in many countries. This article used the Utstein templates for cardiac arrest and resuscitation registries to evaluate outcomes of CPR at Hainan Provincial People's Hospital (HPPH), China.

Methods

A prospective observational study using Utstein CPR registry form to evaluate the epidemiological characteristics and outcomes of 511 resuscitation cases in the emergency department, HPPH.

Results

A total of 511 CPR patients registered were studied. Higher cardiac arrest rates were observed for the group of patients who were 40-70 years old. In preexisting chronic diseases, cardiovascular diseases (190, 37.2%) cerebrovascular diseases (48, 9.4%) and respiratory diseases (39, 7.6%) were common in the recruited patients. (173, 33.9%) of the cardiac arrest patients had underlying cardiac causes, of which 109 (21.3%) had acute myocardial infarct (AMI). Eighty (15.7%) patients had ventricular fibrillation as the first witnessed arrest rhythm. The return of spontaneous circulation (ROSC) and survival to discharge rates were 47.0% and 13.5% in the in-hospital cardiac arrest (IHCA) group but 16.7% and 4.7% in out-of-hospital cardiac arrest (OHCA) group (p<0.01) respectively.

Conclusions

This study indicated that the cardiovascular diseases, cerebrovascular diseases, and respiratory diseases were the most common preexisting chronic diseases. Myocardial infarct, stroke and trauma were the most common precipitation cause of cardiac arrest in the recruited patients. The rate of ROSC and survival to discharge for the patients with IHCA were higher than the ones with OHCA, but figures were still low. (Hong Kong j.emerg.med. 2011;18:391-396)

[Comparison of curative effect and prognosis analysis of patients with spinal metastases treated by percutaneous vertebroplasty combined with postoperative radiotherapy and radiotherapy alone]

Objective: To evaluate the efficacy of percutaneous vertebroplasty(PVP) combined with postoperative radiotherapy and radiotherapy alone in the treatment of spinal metastatic tumors and to evaluate the prognostic factors for survival. Methods: From December 2011 to December 2015, according to the choice of treatment, patients in group A(60 cases) were treated with PVP combined with postoperative radiotherapy and those in group B(50 cases) underwent radiotherapy alone, age, sex, primary tumor type , and other basic characteristics were analyzed in both groups in department of orthopedics and radiotherapy department, 307 Hospital of the People's Liberation Army. The pain visual analogue scale(visual analogue scale, VAS), tumors of the spine instability score(the spinal instability neoplastic score and sins), physical status score(Karnofsky performance score and KPS) were used to evaluate pain, spinal stability improvement and physical condition. Kaplan-Meier was used to analyze the survival rates of two groups of patients and the influence of primary tumor types on the survival of patients; Cox proportional hazard model was used to calculate the correlations between survival and visceral metastases, system medical treatment, vertebral number before treatment and physical condition. Results: There was no significant difference in baseline data between the two groups(P>0.05). The VAS in the group A was significantly lower than the scores in the group B at 1 month, 3 months, 6 months, and 12 months after surgery. The SINS score dropped from(7.8±1.2) to(6.3±0.9)(1 month), (6.1±0.8)(3 months) in patients with PVP combined with postoperative radiotherapy(P<0.05), the SINS score of radiotherapy patients simply dropped from(7.6±0.9) to(7.4±0.7)(1 month), (7.3±0.6)(3 months), and there was no statistically significant difference(P=0.12). The survival rates of 6 months, 1 years, and 3 years were similar between two groups(P>0.05). The influence of different types of primary tumors on the survival time of the patients was statistically significant(P<0.05). Multiple analysis showed that the internal organs metastasis, systemic medical treatment, the number of vertebral bodies and the physical condition were the important prognostic factors of the survival in patients with spinal metastases. Conclusion: PVP combined with postoperative radiotherapy for spinal metastases is better than radiotherapy alone in the treatment of relieving pain, maintaining the stability of vertebral body and improving the quality of life of patients. Survival prognosis was similar in two groups. The types of primary tumors, visceral metastasis, systemic medical treatment, the number of vertebral bodies and the physical condition are important prognostic factors in the survival of patients with spinal metastases.

[Efficiency of the Modified Ottawa ankle rules for the differential diagnosis of fracture in acute foot and ankle injury]

Objective: To evaluate the efficiency of modified Ottawa Ankle Rules (OAR) for the differential diagnosis of fractures in acute foot and ankle injuries. Methods: From October 2016 to December 2016, 272cases (135 males and 137 females) of foot and ankle injury in emergency department of Tianjin Hospital were prospective enrolled in the study.The median age was 27.5 years (7-87); left limb 155, right 117 cases; injury time ranged from 0.3 to 24 h (median 4 h). Conventional and modified OAR was applied on physical examination, subsequently radiography performed to determine the occurrence of fractures.The efficiency of the two methods were compared and analyzed. Results: Fractures were found in 100 cases (36.8%), 49 cases of ankle and 51 cases of foot fractures.With the imaging results as the standard, the sensitivity for conventional and modified OAR were 93.0% and 100%, specificity were 9.9% and 8.7%, the positive predictive value were 37.5% and 38.9%, the negative predictive value were 70.8% and 100%, the accuracy were 40.4% and 42.3%, missed diagnosis rate were 7% and 0% respectively.The sensitivity, positive likelihood ratio, positive predictive value, negative predictive value, accuracy, negative likelihood ratio and missed diagnosis ratio were better than in modified OAR compared with Conventional OAR, while the specificity was slightly lower compared to Conventional OAR.The Kappa value of modified OAR was 0.065 (P>0.05), which is better than conventional OAR.Conventional OAR can reduce 6.3% (17/272) X-ray and modified OAR decline 5.5% (15/272). Conclusion: Modified OAR significantly reduces the rate of missed diagnosis of foot fractures, but its specificity is poor. Ultrasound can be assisted to improve the specificity and reduce the number of unnecessary X-rays.

Nonlinear wave propagation in porous materials based on the Biot theory

Nonlinearity must be considered with some porous granular media because of the large deformation under seismic waves. In this study, the propagation of nonlinear waves in porous media is studied based on the Biot theory and the governing equations are obtained by the Lagrangian formulation. Three new nonlinear parameters are introduced to consider the coupled nonlinearity between the solid and fluid components in porous media. It is shown that an additional nonlinear wave with a double frequency is generated by the coupling effect of linear fast and slow waves. When only a shear wave is applied at the source, no double-frequency nonlinear wave is predicted and three nonlinear longitudinal waves are generated. On the basis of the practical case studies, the effect of strong nonlinearity is computed under the influence of a one-dimensional single longitudinal wave source and a single shear wave source.

Zigzag C2N nanoribbons with edge modifications as multi-functional spin devices

Recently, a holey two-dimensional (2D) C₂N crystal with a wide band gap has been successfully synthesized. However, its non-magnetic property largely limits real applications in spintronics. Here we find that edge magnetism can be introduced by tailoring the holey 2D C₂N crystal into nanoribbons with zigzag edges. When edge N atoms are bare or passivated by H atoms, the device can be used to design high-performance thermospin devices and thermal rectifiers. This is ascribed to the emergence of a spin semiconducting property with a wide band gap. Moreover, if the edge N atoms are passivated by O atoms, the device shows a half-metallic property; meanwhile an obvious spin Seebeck effect can also be observed when a temperature difference is applied across the device.

[Diagnossis and treatment of complicated anterior teeth esthetic defects by combination of whole-process digital esthetic rehabilitation with periodontic surgery]

OBJECTIVE

To explore a new method of whole-process digital esthetic prosthodontic rehabilitation combined with periodontic surgery for complicated anterior teeth esthetic defects accompanied by soft tissue morphology, to provide an alternative choice for solving this problem under the guidance of three-dimensional (3D) printing digital dental model and surgical guide, thus completing periodontic surgery and digital esthetic rehabilitation of anterior teeth.

METHODS

In this study, 12 patients with complicated esthetic problems accompanied by soft tissue morphology in their anterior teeth were included. The dentition and facial images were obtained by intra-oral scanning and three-dimensional (3D) facial scanning and then calibrated. Two esthetic designs and prosthodontic outcome predictions were created by computer aided design /computer aided manufacturing (CAD/CAM) software combined with digital photography, including consideration of white esthetics and comprehensive consideration of pink-white esthetics. The predictive design of prostheses and the facial appearances of the two designs were evaluated by the patients. If the patients chose the design of comprehensive consideration of pink-white esthetics, they would choose whether they would receive periodontic surgery before esthetic rehabilitation. The dentition design cast of those who chose periodontic surgery would be 3D printed for the guide of periodontic surgery accordingly.

RESULTS

In light of the two digital designs based on intra-oral scanning, facing scanning and digital photography, the satisfaction rate of the patients was significantly higher for the comprehensive consideration of pink-white esthetic design (P<0.05) and more patients tended to choose priodontic surgery before esthetic rehabilitation. The 3D printed digital dental model and surgical guide provided significant instructions for periodontic surgery, and achieved success transfer from digital design to clinical application. The prostheses were fabricated by CAD/CAM, thus realizing the whole-process digital esthetic rehabilitation.

CONCLUSION

The new method for esthetic rehabilitation of complicated anterior teeth esthetic defects accompanied by soft tissue morphology, including patient-involved digital esthetic analysis, design, esthetic outcome prediction, 3D printing surgical guide for periodontic surgery and digital fabrication is a practical technology. This method is useful for improvement of clinical communication efficiency between doctor-patient, doctor-technician and doctors from different departments, and is conducive to multidisciplinary treatment of this complicated anterior teeth esthetic problem.

[A novel tissue-engineered bone constructed by using human adipose-derived stem cells and biomimetic calcium phosphate scaffold coprecipitated with bone morphogenetic protein-2]

OBJECTIVE

To construct a novel biomimetic calcium phosphate (BioCaP) scaffold loaded with bone morphogenetic protein-2 (BMP-2), and to investigate its role in the osteogenesis of human adipose-derived stem cells (hASCs) in vitro and in vivo.

METHODS

The BioCaP scaffold coprecipitated with BMP-2 (BMP-2-BioCaP) was constructed in this study. Field emission scanning electron microscopy (SEM) was used to analyze the morphology of the surfaces. The release kinetics was measured to evaluate the slow-release characteristics in vitro. BMP-2-BioCaP was immersed in proliferation medium (PM) or osteogenic medium (OM), respectively. The supernatants were collected and used to culture hASCs in vitro. Cell numbers were determined using the cell-counting kit-8 (CCK-8) to assess the cell proliferation. After 7 and 14 days, alkaline phosphatase (ALP) staining and quantification were performed to test the activity of ALP. After 14 and 21 days, the calcification deposition was determined by alizarin red S (ARS) staining and quantification. The expressions of the osteoblast-related genes were tested on day 4 and day 14. In the in vivo study, 6 nude mice were used and implanted subcutaneously into the back of the nude mice for 4 groups: (1) BioCaP scaffold only, (2) BioCaP scaffold+hASCs, (3) BMP-2-BioCaP scaffold, (4) BMP-2-BioCaP scaffold+hASCs (test group). After 4 weeks of implantation, hematoxylin-eosin (HE) staining was performed to evaluate the in vivo osteogenesis of hASCs.

RESULTS

SEM observations showed that BioCaP and BMP-2-BioCaP scaffold were entirely composed of straight, plate-like and sharp-edged crystal units, and the length of the crystal units varied between 5 and 10 μm. Release kinetics analysis demonstrated that BMP-2 incorporated with BioCaP could be released at certain concentration and last for more than 21 days, and the accumulative protein release could reach 20%. CCK-8 assays showed that cell proliferation was not significantly affected by BMP-2-BioCaP. ALP activity was higher by the induction of OM+BMP-2-BioCaP than of the other groups (P<0.01). More mineralization deposition and more expressions of osteoblast-related genes such as Runt-related transcription factor 2 (RUNX2), ALP, osteopontin (OPN) and osteocalcin (OC) were determined in the OM+BMP-2-BioCaP group at different time points (P<0.01). HE staining showed that, in the test group and BMP-2-BioCaP scaffold group, the extracellular matrix (ECM) with eosinophilic staining were observed around hASCs, and newly-formed bone-like tissues could be found in ECM around the scaffold materials. Moreover, compared with the BMP-2-BioCaP scaffold group, more bone-like tissues could be observed in ECM with typical structure of bone tissue in the test groups. No obvious positive results were found in the other groups.

CONCLUSION

BMP-2-BioCaP scaffold could achieve slow-release of BMP-2 and promote the osteogenic differentiation of hASCs in vitro and in vivo. The novel tissue-engineered bone composed of hASCs and BMP-2-BioCaPis promising for the repair of bone defect.

[Dental implantation and soft tissue augmentation after ridge preservation in a molar site: a case report]

For ideal implant rehabilitation, an adequate bone volume, optical implant position, and stable and healthy soft tissue are required. The reduction of alveolar bone and changes in its morphology subsequent to tooth extraction will result in insufficient amount of bone and adversely affect the ability to optimally place dental implants in edentulous sites. Preservation of alveolar bone volume through ridge preservation has been demonstrated to reduce the vertical and horizontal contraction of the alveolar bone crest after tooth extraction and reduce the need for additional bone augmentation procedures during implant placement. In this case, a patient presented with a mandible molar of severe periodontal disease, the tooth was removed as atraumatically as possible and the graft material of Bio-Oss was loosely placed in the alveolar socket without condensation and covered with Bio-Gide to reconstruct the defects of the alveolar ridge. Six months later, there were sufficient height and width of the alveolar ridge for the dental implant, avoiding the need of additional bone augmentation and reducing the complexity and unpredictability of the implant surgery. Soft tissue defects, such as gingival and connective tissue, played crucial roles in long-term implant success. Peri-implant plastic surgery facilitated development of healthy peri-implant structure able to withstand occlusal forces and mucogingival stress. Six months after the implant surgery, the keratinized gingiva was absent in the buccal of the implant and the vestibular groove was a little shallow. The free gingival graft technique was used to solve the vestibulum oris groove supersulcus and the absence of keratinized gingiva around the implant. The deepening of vestibular groove and broadening of keratinized gingiva were conducive to the long-term health and stability of the tissue surrounding the implant. Implant installation and prosthetic restoration showed favorable outcome after six months.

Carbon-based molecular devices: Fano effects controlled by the molecule length and the gate voltage

Fano effect is an important quantum phenomenon in mesoscopic systems, which arises from an interference between the localized state and the extended state. Here we observe an obvious Fano effect near the Fermi level in an all-carbon molecular device consisting of an acene molecule sandwiched between two zigzag graphene nanoribbon (ZGNR) electrodes. By increasing the length of the molecule, an extended state gradually evolves into a localized state. With the aid of the nearby extended state, a Fano effect is achieved. Using a gate voltage, we can easily tune the Fano effect induced by the single-transmission channel. When the spin degree of freedom is involved, the all-carbon device can show a half-metallic property with positive or negative 100% spin polarization at the Fermi level under the gate voltage; meanwhile the spin thermoelectric effect can also be enhanced.

Identification of allocryptopine and protopine metabolites in rat liver S9 by high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry

RATIONALE

Allocryptopine (AL) and protopine (PR) have been extensively studied because of their anti-parasitic, anti-arrhythmic, anti-thrombotic, anti-inflammatory and anti-bacterial activity. However, limited information on the pharmacokinetics and metabolism of AL and PR has been reported. Therefore, the purpose of the present study was to investigate the in vitro metabolism of AL and PR in rat liver S9 using a rapid and accurate high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (HPLC/QqTOFMS) method.

METHODS

The incubation mixture was processed with 15% trichloroacetic acid (TCA). Multiple scans of AL and PR metabolites and accurate mass measurements were automatically performed simultaneously through data-dependent acquisition in only a 30-min analysis. The structural elucidations of these metabolites were performed by comparing their changes in accurate molecular masses and product ions with those of the precursor ion or metabolite.

RESULTS

Eight and five metabolites of AL and PR were identified in rat liver S9, respectively. Among these metabolites, seven and two metabolites of AL and PR were identified in the first time, respectively. The demethylenation of the 2,3-methylenedioxy, the demethylation of the 9,10-vicinal methoxyl group and the 2,3-methylenedioxy group were the main metabolic pathways of AL and PR in liver S9, respectively. In addition, the cleavage of the methylenedioxy group of the drugs and subsequent methylation or O-demethylation were also the common metabolic pathways of drugs in liver S9. In addition, the hydroxylation reaction was also the metabolic pathway of AL.

CONCLUSIONS

This was the first investigation of in vitro metabolism of AL and PR in rat liver S9. The detailed structural elucidations of AL and PR metabolites were performed using a rapid and accurate HPLC/QqTOFMS method. The metabolic pathways of AL and PR in rat were tentatively proposed based on these characterized metabolites and early reports. Copyright © 2016 John Wiley & Sons, Ltd.

Bone micro-architectural analysis of mandible and tibia in ovariectomised rats: A quantitative structural comparison between undecalcified histological sections and micro-CT

OBJECTIVES

This study aims to evaluate if micro-CT can work as a method for the 3D assessment and analysis of cancellous bone by comparing micro-CT with undecalcified histological sections in OVX rats.

METHODS

The mandible and tibia of sham, ovariectomised (OVX) and zoledronate-injected ovariectomised (OVX-ZOL) rats were assessed morphometrically. Specimens were scanned by micro-CT. Undecalcified histological sections were manufactured from the specimen scanned by micro-CT and stained with haematoxylin and eosin. Bivariate linear regressions and one-way analysis of variance were undertaken for statistics using SPSS 16.0.1 software.

RESULTS

There were highly significant correlations between undecalcified histological sections and micro-CT for all parameters (bone volume density (BV/TV), bone surface density (BS/BV), trabecular thickness (Tb.Th), trabecular number (Tb.N), and trabecular separation (Tb.Sp))in the mandible and tibia. Bone histomorphometric parameters analysed by both methods exhibited significant differences among sham, OVX, and OVX-ZOL groups. There were significant correlations between mandible and tibia in BV/TV, BS/BV, and Tb.Sp.

CONCLUSIONS

Micro-CT is a complementary tool to histological sections in basic research that could improve our understanding of bone histomorphometry. The mandible can be used as an effective site to assess bone morphometry of OVX or metabolic bone disease rat models.Cite this article: H. Liu, W. Li, Y. S. Liu, Y. S. Zhou. Bone micro-architectural analysis of mandible and tibia in ovariectomised rats: A quantitative structural comparison between undecalcified histological sections and micro-CT. Bone Joint Res 2016;5:253-262.

Effects of nucleotide usage on the synonymous codon usage patterns of biofilm-associated genes in Haemophilus parasuis

To provide a new perspective on the evolutionary characteristics shaping the genetic diversity of Haemophilus parasuis biofilms, the relative synonymous codon usage values, codon usage bias values, effective number of codons (ENC) values, codon adaptation index (CAI) values, and the base components were calculated. Our objective was to implement a comparative analysis to evaluate the dynamic evolution of biofilm-associated genes in H. parasuis. The analysis of genetic diversity provides evidence that some biofilm-associated genes have similar genetic features. However, other genes show some variations in genetic direction. Furthermore, preferential selection of the synonymous codons and amino acids is apparent in biofilm-associated genes. Additionally, the ENC and CAI data from this study all strongly suggested that biofilm-associated genes may depend on deoptimization to adapt to environmental changes, and the mutation effect of biofilm-associated genes in H. parasuis plays an important role in shaping the genetic features. Our results reveal that the mutations of biofilm-associated genes form a set of sophisticated strategies for combating the environmental changes arising from the host cell in the evolution of H. parasuis.

[Curative effect analysis of posterior decompression and internal fixation for spinal metastases epidural spinal cord compression]

OBJECTIVE

To explore the effects of posterior decompression and internal fixation for spinal metastases epidural spinal cord compression (MESCC) and analyze the related factors of postoperative ambulation function.

METHODS

Clinical data of 67 cases with MESCC who received thoracic posterior decompression and internal fixation in our department from January 2006 to December 2014 was retrospectively analyzed. Information about patients' age, gender, pathological type of primary tumor, Karnofsky performance status (KPS) score, pre-operative and postoperative visual analogue scale, preoperative Frankel grade, pre-operative and postoperative imaging characteristics (number of thoracic vertebrae metastases, location, compression fractures of vertebral bodies), time of movement dysfunction and survival was collected.

RESULTS

At the end of the follow-up of 67 cases, 57 cases were dead, 10 cases were alive, and the median survival was 8.1 months (1.2-91.9 months).38 cases (67%) died within one year, 50 cases (88%) died within two years. Visual analogue scale of preoperative and postoperative dropped from (5.67±1.67) points to (2.11±1.39) points (P<0.001), 38 (53%) patients' Frankel grade improved at least one grade. Among the 34 cases who were unable to walk, 15 cases regained ability of ambulation after surgery. The patients with KPS scores greater than 80 points and/or had preoperative ambulation ability, tended to have better postoperative ambulatory function.

CONCLUSIONS

Posterior decompression and internal fixation for MESCC is effective, and can effectively relieve pain and spinal cord compression, improve neurological function and the quality of life. The ambulatory functional outcomes after surgery are dependent on KPS scores, the occurrence time of neurological dysfunction, preoperative ambulatory status.

Compact high-power microwave divider and combiner

A novel, compact, TM01-TE10 mode power divider and a novel, compact, four-way TE10-TM01 mode power combiner were theoretically designed and experimentally tested as a proof of principle. The theoretical and experimental S parameters are consistent with each other. High-power experiments show that their power capacities are no less than 1.5 GW and 3 GW, respectively. The devices have the merits of high power capacities and low insertion losses.

Positive expression of insulin-like growth factor-1 receptor is associated with a positive hormone receptor status in ovarian cancer

Summary

PURPOSE

Ovarian cancer is the most deadly of all gynecologic malignancies, due in part to the diagnosis at an advanced stage caused by the deficiency of specific marks and symptoms, by the absence of reliable tests for screening, and by early detection.

MATERIALS AND METHODS

Insulin-like growth factor-I (IGF-I) is known to be involved in the development and promotion of diverse examples of solid tumors including ovarian cancer. IGF-I levels in local tissue are subject to both endocrine and paracrine/autocrine regulation.

RESULTS

Most patients will react initially to treatment, but almost 70% of them will have a recurrence. Consequently, new therapeutic modalities are urgently required to overcome chemoresistance observed in ovarian cancer patients. IGF-1R expression was evaluated immunohistochemically in tissue microarray blocks constructed from 1,200 ovarian cancer samples collected from three medical institutions.

CONCLUSION

Evidence accumulates suggesting that the insulin/insulin growth factor (IGF) pathways could play a good therapeutic target in various cancers, including ovarian cancer.