Construction of porous structure on the surface of PLLA/β-tricalcium scaffold and its effect on cell adhesion / 西安交通大学学报(医学版)

【Objective】 To construct a 3D printed PLLA/β-tricalcium (PLLA/β-TCP) bone tissue engineering scaffold surface porous structure through simple treatment with NaOH solution, increase the roughness and hydrophilicity of the scaffold, and promote cell adhesion on the scaffold surface. 【Methods】 The PLLA/β-TCP mesh scaffold was prepared by 3D printing melt deposition molding technology, and the scaffold was roughed by NaOH etching. The effects of NaOH concentration and time on the scaffold were observed according to the microstructure, energy spectrum, contact angle, mechanics, and cell adhesion of the scaffold. 【Results】 The PLLA/β-TCP composite scaffold constructed by melt deposition technology had a pre-set porous structure, and the pores were interconnected. After NaOH etching, a porous structure with both macroscopic and microscopic pores was formed. The increase in any of the NaOH concentration and time parameters would lead to the increase of pore diameter and surface roughness. When the NaOH treatment parameter was 0.1 mol/L (9 h), it could significantly reduce the water contact angle on the surface of the scaffold, and had no significant effect on the compressive strength of the scaffold. In vitro cell testing showed that the surface porous composite scaffold etched with NaOH had more advantages in the adhesion and proliferation of BMSCs. 【Conclusion】 Using NaOH to process 3D printing of PLLA/β-TCP bone tissue engineering scaffolds can effectively improve the surface morphology of the scaffold, and optimize its hydrophilicity and cell adhesion.

Identification and expression analysis of TCP family members in tobacco (Nicotiana tabacum L.) / 生物工程学报

TCP family as plant specific transcription factor, plays an important role in different aspects of plant development. In order to screen TCP family members in tobacco, the homologous sequences of tobacco and Arabidopsis TCP family were identified by genome-wide homologous alignment. The physicochemical properties, phylogenetic relationships and cis-acting elements were analyzed by bioinformatics. The homologous genes of AtTCP3/AtTCP4 were screened, and RT-qPCR was used to detect the changes of gene expression upon 20% PEG6000 treatment. The results show that tobacco contains 63 TCP family members. Their amino acid sequence length ranged from 89 aa to 596 aa, and their protein hydropathicity grand average of hydropathicity (GRAVY) ranged from -1.147 to 0.125. The isoelectric point (pI) ranges from 4.42 to 9.94, the number of introns is 0 to 3, and the subcellular location is all located in the nucleus. The results of conserved domain and phylogenetic relationship analysis showed that the tobacco TCP family can be divided into PCF, CIN and CYC/TB1 subfamilies, and each subfamily has a stable sequence. The results of cis-acting elements in gene promoter region showed that TCP family genes contain low docile acting elements (LTR) and a variety of stress and metabolic regulation related elements (MYB, MYC). Analysis of gene expression patterns showed that AtTCP3/AtTCP4 homologous genes (NtTCP6, NtTCP28, NtTCP30, NtTCP33, NtTCP42, NtTCP57, NtTCP63) accounted for 20% PEG6000 treatment significantly up-regulated/down-regulated expression, and NtTCP30 and NtTCP57 genes were selected as candidate genes in response to drought. The results of this study analyzed the TCP family in the tobacco genome and provided candidate genes for the study of drought-resistance gene function and variety breeding in tobacco.

On the use of radiobiological-based optimization functions in radiotherapy treatment planning for prostate and head and neck cases on Monaco and Eclipse TPS / Sobre el uso de funciones de costo basadas en radiobiología en la planeación de tratamientos de radioterapia para casos de próstata y cabeza y cuello en los TPS Monaco y Eclipse

INTRODUCTION Radiobiological-based optimization functions for radiotherapy treatment planning involve dose-volume effects that could allow greater versatility when shaping dose distributions and DVHs than traditional dose volume (DV) criteria. Two of the most commercially available TPS (Monaco and Eclipse) already offer biological-based optimization functions, but they are not routinely used by most planners in clinical practice. Insight into the benefits of using EUD, TCP/NTCP-based cost functions in Monaco and Eclipse TPS was gained by comparing biological-based optimizations and physical-based optimizations for prostate and head and neck cases. METHODS Three prostate and three H&N cases were retrospectively optimized in Monaco and Eclipse TPS, using radiobiological-based cost functions vs DV-based cost functions. Plan comparison involved ICRU Report 83 parameters D95%, D50%, D2% and TCP for the PTV, and NTCP and RTOG tolerance doses for OARs. RESULTS Although there were differences between Monaco and Eclipse plans due to their dissimilar optimization and dose calculation algorithms as well as optimization functions, both TPS showed that radiobiological-based criteria allow versatile tailoring of the DVH with variation of only one parameter and at most two cost functions, in contrast to the use of three to four DV-based criteria to reach a similar result. CONCLUSION Despite the use of a small sample, optimization of three prostate and three head and neck cases allowed the exploration of optimization possibilities offered by two of the most commercially available TPS on two anatomically dissimilar regions. Radiobiological-based optimization efficiently drives dose distributions and DVH shaping for OARs without sacrifice of PTV coverage. Use of EUD-based cost functions should be encouraged in addition to DV cost functions to obtain the best possible plan in daily clinical practice

INTRODUCCION Las funciones de optimización basadas en radiobiología para la planificación del tratamiento de radioterapia implican efectos dosis volumen que podrían permitir una mayor versatilidad a la hora de dar forma a las distribuciones de dosis y DVH que los tradicionales criterios dosis-volumen (DV). Dos de los TPS más disponibles comercialmente (Mónaco y Eclipse) ya ofrecen productos de funciones de optimización de base biológica, pero la mayoría de los planificadores no las utilizan de forma rutinaria en la práctica clínica. El conocimiento de los beneficios del uso de las funciones de costos basadas en EUD, TCP/NTCP en Mónaco y Eclipse TPS se obtuvo comparando optimizaciones de base biológica y optimizaciones físicas para casos de próstata y cabeza y cuello. MÉTODOS Tres próstatas y tres casos de H&N en Mónaco y Eclipse TPS fueron optimizadas retrospectivamente usando funciones de costos basadas en radiobiología vs funciones de costos basadas en DV. La comparación de planes involucró los parámetros del Informe ICRU 83 D95%, D50%, D2% y TCP para el PTV, y dosis de tolerancia NTCP y RTOG para OAR. Resultados. Aunque hubo diferencias entre los planes Mónaco y Eclipse, debido a sus diferentes algoritmos de optimización y cálculo de dosis, así como funciones de optimización, ambos TPS demostraron que el criterio basado en radiobiología permiten una adaptación versátil del DVH con variación de un solo parámetro y como máximo dos funciones de costos, en contraste con el uso de tres o cuatro criterios basados en DV para alcanzar un resultado similar. CONCLUSIÓN A pesar del uso de una muestra pequeña, la optimización de tres casos de próstata y tres de cabeza y cuello permitió la exploración de las posibilidades de optimización que ofrecen dos de los TPS más disponibles comercialmente en dos regiones anatómicamente diferentes. La optimización basada en radiobiología impulsa de manera eficiente las distribuciones de dosis y la configuración de DVH para OAR sin sacrificar Cobertura de PTV. Se debe fomentar el uso de funciones de costos basadas en EUD además de las funciones de costos DV para obtener el mejor posible plan en la práctica clínica diaria

Bioinformatics analysis and function prediction of ginseng TCP transcription factor family / 中国中药杂志

The longevity mechanism of ginseng(Panax ginseng) is related to its strong meristematic ability. In this paper, this study used bioinformatic methods to identify the members of the ginseng TCP gene family in the whole genome and analyzed their sequence characteristics. Then, quantitative real-time fluorescent PCR was performed to analyze the TCP genes containing elements rela-ted to meristem expression in the taproots, fibrous roots, stems, and leaves. According to the data, this study further explored the expression specificity of TCP genes in ginseng tissues, which facilitated the dissection of the longevity mechanism of ginseng. The ginseng TCP members were identified and analyzed using PlantTFDB, ExPASy, MEME, PLANTCARE, TBtools, MEGA and DNAMAN. The results demonstrated that there were 60 TCP gene family members in ginseng, and they could be divided into two classes: Class Ⅰ and Class Ⅱ, in which the Class Ⅱ possessed two subclasses: CYC-TCP and CIN-TCP. The deduced TCP proteins in ginseng had the length of 128-793 aa, the isoelectric point of 4.49-9.84 and the relative molecular mass of 14.2-89.3 kDa. They all contained the basic helix-loop-helix(bHLH) domain. There are a variety of stress response-related cis-acting elements in the promoter regions of ginseng TCP genes, and PgTCP20-PgTCP24 contained the elements associated with meristematic expression. The transcription levels of PgTCP20-PgTCP24 were high in fibrous roots and leaves, but low in stems, indicating the tissue-specific expression of ginseng TCP genes. The Class Ⅰ TCP members which contained PgTCP20-PgTCP23, may be important regulators for the growth and development of ginseng roots.

International communication system of acupuncture-moxibustion based on OSI model / 中国针灸

Borrowing the open system interconnection (OSI) model of internet protocol and the 5W theory in communication studies, the links in the international communication of acupuncture-moxibustion can be classified into seven layers: physical layer, data link layer, network layer, transport layer, session layer, presentation layer and application layer, therefore it is built an OSI model of international communication system of acupuncture-moxibustion. It is pointed out that present international communication system of acupuncture-moxibustion is similar to the user datagram protocol (UDP) in internet technology. Evidence-based medicine (EBM) plays a key role to modernize acupuncture- moxibustion theory based upon its clinical effects. According to phenomenon-taking by classified analogy, it is found that the PICO model of EBM agrees pretty well with the "three-way handshakes" mechanism of the internet transmission control protocol (TCP), which is promising to construct an international discourse of acupuncture-moxibustion compatible with western medicine. Thus it will benefit to explore the scientific connotation of acupuncture-moxibustion theory and significantly improve the international prestige of acupuncture-moxibustion.

Antibacterial Efficacy and Drug-release Behavior Study of β-tricalcium Phosphate Micro-granules Against Staphylococcus aureus and Escherichia coli

@#Introduction: This study aims to investigate different residue sizes of β-tricalcium phosphate (β-TCP) micro-granules as carriers to assess antibacterial activity and drug-control release behavior of ampicillin (AMP-) and antimycotic (AMC-). Incorporation of antibiotic into the β-TCP micro-granules and it sustain release behavior could be used as alternative solution to reduce the risk of osteomyelitis and bone infections risks. Methods: Three different residue sizes (less than 300 µm, 300 µm and 600 µm) were prepared and coated with antibiotics solution (20 µg/µl of ampicillin and 100X antimycotic solution) by using two methods; dip and stream coating. After 72 h, 1.5 mL of distilled water was added to the treated (β-TCP) micro-granules at two different pH value (5.0 and 7.4). The extracted solution was further analyzed by Kirby Bauer disc diffusion test and spectrophotometer assay. Results: The solution containing AMC-(β-TCP) micro-granules with the size of 300 µm residue produced the largest inhibition zones against Escherichia coli (E. coli). All residue sizes coated with AMP- showed no antibacterial activity against both strains; Staphylococcus aureus (S. aureus) and E.coli. Additionally, the release behavior of AMC-(β-TCP) micro-granules was found not depending on the pH, but on the size of residue. Complete drug release was rapidly observed within 48 h. Conclusion: Based on this findings, it showed AMC-(β-TCP) micro-granules had an antibacterial activity against Gram-negative strain. Specifically, it can reduced the growth rate of E. coli and the rapid release behavior of AMC(β-TCP) micro-granules help in minimizing the risk-infections in early stage of implantation.

Polyphyllin I alleviates osteoblasts injuries induced by TCP wear particles in vitro via inhibition of autophagy / 中草药

Objective: To observe the effect of polyphyllin I (PPI) on osteoblasts injuries induced by tricalcium phosphate (TCP) wear particles in vitro, and explain its regulation mechanisms. Methods: Primary osteoblasts obtained from the calvaria of neonatal SD rat by the series of digestion were identified with ALP staining. The osteoblasts were treated with TCP wear particles (TCP, 0.1 mg/mL) for 48 h to establish an in vitro injuries model of the calvarial osteoblasts. The experiment was randomly divided into control group, model (TCP, 0.1 mg/mL) group, PPI (30 μg/mL) group and PPI (100 μg/mL) group. CCK-8 and chemical colorimetry were used to examine cell viability and lactic dehydrogenase (LDH) content in culture media; Real-time PCR was performed to detect mRNA levels of ALP, Collagen I and RUNX2 in osteoblasts; The flow cytometry was used to examine apoptosis of osteoblasts using Annexin V/PI double staining; When the osteoblasts were treated for 14 d, mineral nodules formation was observed with alizarin S staining; Western blot was applied to examine proteins expression of Bax, Bcl-2, cleaved Caspase-3, Atg5, p62, and microtubule associated protein 1 light chain3 (LC-3). Results: Compared with control group, model group showed that the cell viability of osteoblasts, mRNA levels of ALP, Collagen I and RUNX2, and mineral nodules formation were significantly decreased; LDH content, percentage of apoptosis and proteins expression of Bax, cleaved Caspase-3, Atg5, LC-3 and the ratio of LC-3II/LC-3I were obviously increased in calvarial osteoblasts, whereas proteins expression of Bcl-2 and p62 was remarkably decreased. Compared with model group, PPI groups indicated that cell viability of osteoblasts, mRNA levels of ALP, Collagen I and RUNX2, and mineral nodules formation were dramatically increased; LDH content, percentage of apoptosis, protein expressions of Bax, cleaved Caspase-3, Atg5, and LC-3 and the ratio of LC-3II/LC-3I were obviously decreased, but Bcl-2 and p62 expression were obviously increased. Conclusion: PPI alleviates osteoblasts injuries induced by TCP wear particles via inhibition of autophagy.

Effect of psoralen on rat osteoblasts injuries induced by TCP wear particles in vitro and its mechanism / 中国应用生理学杂志

To investigate the effect and mechanism of psoralen on calvarial osteoblasts injuries caused by tricalcium phosphate (TCP) wear particles in vitro. Primary osteoblasts were obtained from the calvaria of neonatal SD rat by the series of digestion and were identified with ALP staining. Calvarial osteoblasts were treated with TCP wear particles for 48 h to establish the in vitro model of osteoblasts injuries. The rat osteoblasts were randomly divided into control group, TCP wear particles (0.1 mg/ml) group, psoralen treated (at the concentrations of 10, 10, 10 mol/L) groups. WST assay and the flow cytometry were used to detect the cell viability of osteoblasts and apoptosis, respectively. Chemical colorimetry was performed to examine ALP activity of osteobalsts. When the osteoblasts were treated for 14 day, mineral nodules formation was observed with alizarin red S staining. Western blot was applied to examine protein expressions of glucose regulated protein78/94(GRP78/94), inositol dependent enzyme 1 alpha (IREα), spliced X-box binding protein 1 (XBP1s) and phosphorylated c-Jun N-terminal kinase (p-JNK) in calvarial osteoblasts. Compared with control group, the cell viability of osteoblasts, ALP activity and mineral nodules formation in TCP group were decreased significantly (P＜0.05), while the percentage of apoptosis and protein expressions of GRP78/94, IRE1α, XBP1 and p-JNK were obviously increased in calvarial osteoblasts (P＜0.05). Compared with TCP group, the injuries of calvarial osteoblasts and cell apoptosis in psoralen treated groups were obviously decreased (P＜0.05), and the expression levels of GRP78/94, IRE1α, XBP1 and p-JNK were down-regulated remarkably (P＜0.05). Psoralen prevents osteoblasts injuries caused by TCP wear particles through IRE1α-XBP1s-JNK signaling pathway activation.

Mechanism of CCT2, a new downstream substrate of PDGFRα, on proliferation of tumor cells / 上海交通大学学报（医学版）

Objective: To study the molecular mechanism of chaperonin containing TCP1 subunit 2(CCT2), a new downstream substrate of platelet derived growth factor receptor α(PDGFRα), in tumorigenesis. Methods: Non-small cell lung cancer cell line H1703 was used. Western blotting was used to measure the phosphorylation of CCT2 upon PDGFRα inhibitor Gleevec treatment and PDGF stimulation. H1703 cells were divided into siCon group, siPDGFRα group and siCCT2 group; 48 h later, cell number counting was used to test the effect of CCT2 on cell growth after siRNA transfection. H1703 cells were divided into siCon group, siPDGFRα group, siAKT group and siCCT2 group; Western blotting was used to measure the protein level of PDGFRα and PARP. Cell fractionation was used to detect the cellular localization of CCT2 and co-immunoprecipitation was used to test the interaction between CCT2 and PDGFRα. Results: CCT2 phosphorylation was inhibited by Gleevec and induced by PDGF. Compared to the control group, the number of cells transfected by siCCT2 reduced by 30% (P=0.006). The protein level of PDGFRα was also decreased in siCCT2 transfected cells, whereas the cleavage of PARP was increased. CCT2 was localized in both cytoplasmic and membrane fractions and interacted with PDGFRα directly. Conclusion: CCT2 is a new downstream substrate of PDGFRα. CCT2 can promote tumor cells growth by interacting and stabilizing PDGFRα.

Clinical application of controllable microstructured porous β-TCP bioceramics in the repair of jawbone defects / 中国现代医生

Objective To investigate the clinical application of controllable microstructured porous β-TCP bioceramics in the repair of jawbone defects. Methods From January 2016 to January 2017, 60 cases of jawbone defects who were admitted to our department were randomly assigned to the experimental group and the control group, with 30 cases in each group. In the experimental group, the controllable microstructured porous β-TCP bioceramic was used to repair the bone cavity of the jawbone defect. The control group was not implanted with any bone replacement material. The postoperative bone healing, bone cavity infection rate, and the rejection of the controllable microstructured porous β-TCP bioceramics in the body were studied in both groups. Results In the experimental group, the wounds were healed at stage I after surgery, and no rejection and adverse reactions occurred. A review of CT at 3 months after surgery indicated that the bone was healed well. In the control group, there were 6 cases of postoperative wound infection and 1 case of pathological fractures, who were cured after anti-infection and conservative treatment. CT was reexamined 3 months after surgery, and no obvious changes were found in the defected bone cavity. Conclusion Controllable microstructured porous β-TCP bioceramics can effectively repair jawbone defects as a new bone replacement material, eliminate the dead cavity of bone defect, effectively reduce the infection and pathological fractures caused by the defected bone cavity, and has a good application prospect.

Preparation and Characterization of Nanocomposite Scaffolds (Collagen/β-TCP/SrO) for Bone Tissue Engineering

BACKGROUND: Nowadays, production of nanocomposite scaffolds based on natural biopolymer, bioceramic, and metal ions is a growing field of research due to the potential for bone tissue engineering applications. METHODS: In this study, a nanocomposite scaffold for bone tissue engineering was successfully prepared using collagen (COL), beta-tricalcium phosphate (β-TCP) and strontium oxide (SrO). A composition of β-TCP (4.9 g) was prepared by doping with SrO (0.05 g). Biocompatible porous nanocomposite scaffolds were prepared by freeze-drying in different formulations [COL, COL/β-TCP (1:2 w/w), and COL/β-TCP-Sr (1:2 w/w)] to be used as a provisional matrix or scaffold for bone tissue engineering. The nanoparticles were characterized by X-ray diffraction, Fourier transforms infrared spectroscopy and energy dispersive spectroscopy. Moreover, the prepared scaffolds were characterized by physicochemical properties, such as porosity, swelling ratio, biodegradation, mechanical properties, and biomineralization. RESULTS: All the scaffolds had a microporous structure with high porosity (~ 95–99%) and appropriate pore size (100–200 µm). COL/β-TCP-Sr scaffolds had the compressive modulus (213.44 ± 0.47 kPa) higher than that of COL/β-TCP (33.14 ± 1.77 kPa). In vitro cytocompatibility, cell attachment and alkaline phosphatase (ALP) activity studies performed using rat bone marrow mesenchymal stem cells. Addition of β-TCP-Sr to collagen scaffolds increased ALP activity by 1.33–1.79 and 2.92–4.57 folds after 7 and 14 days of culture, respectively. CONCLUSION: In summary, it was found that the incorporation of Sr into the collagen-β-TCP scaffolds has a great potential for bone tissue engineering applications.

Characterization of bone substitute beta946; -TCP block for maxillofacial reconstruction / Caracterización del bloque beta946; -TCP de sustitución ósea para la reconstrucción maxilofacial

SUMMARY: The aim of this study was to characterize a commercial beta tricalcium phosphate (β-TCP) block allograft for use in maxillofacial reconstruction, evaluating its homogeneity, porosity and mineralization. Two commercial 5 x 5 x10 mm chronOS Vivify β-TCP blocks were used, which were evaluated by a STEM SU-3500 variable pressure scanning electron microscope (SEM-STEM) (Hitachi, Japan). For the semi-quantitative microanalysis of elements, the QUANTAX 100 energy dispersive x-ray spectrometer detector (EDX) (Bruker, Germany) was used. The homogeneity of the structural morphology, macropore and micropore size and component homogeneity were evaluated. The microscopic analysis showed micropores of 164.92 mm (± 35.032 mm) in diameter in the outer area and micropores in the inner area of 54.44 mm (± 17.676 mm). The formation of porosities and irregularities present in the block was heterogeneous between the outer and inner surfaces. The mineral content of the blocks presented homogeneity with the presence of carbon (2.02 %), oxygen (44.33 %), phosphate (16.62 %) and calcium (37.87 %). The β-TCP block can be used in bone reconstruction but the presence of reduced macropore and micropore sizes could limit efficiency in the substitution and bone regeneration phase.

RESUMEN: El objetivo de este estudio fue caracterizar un aloinjerto de bloqueo de fosfato tricálcico (β-TCP) comercial para su uso en la reconstrucción maxilofacial, evaluando su homogeneidad, porosidad y mineralización. Se utilizaron dos bloques comerciales de 5 x 5 x 10 mm de vivify β-TCP de chronOS, que se evaluaron mediante un microscopio electrónico de barrido de presión variable STEM SU-3500 (SEM-STEM) (Hitachi, Japón). Para el microanálisis de elementos semicuantitativo, se utilizó el detector de espectrómetro de rayos X de dispersión de energía QUANTAX 100 (EDX) (Bruker, Alemania). Se evaluó la homogeneidad de la morfología estructural, el tamaño del macroporo y microporo y la homogeneidad de los componentes. El análisis microscópico mostró microporos de 164,92 mm (± 35,032 mm) de diámetro en el área externa y microporos en el área interna de 54,44 mm (± 17,676 mm). La formación de porosidades e irregularidades presentes en el bloque fue heterogénea entre las superficies externas e internas. El contenido mineral de los bloques presentó homogeneidad con la presencia de carbono (2,02 %), oxígeno (44,33 %), fosfato (16,62 %) y calcio (37,87 %). El bloque β-TCP se puede utilizar en la reconstrucción ósea, pero la presencia de macroporos y tamaños de microporos reducidos podría limitar la eficacia en la fase de sustitución y regeneración ósea.

Mechanical Properties and Biological Characteristics of the Porous 3D-Printed β-TCP Composite Scaffolds / 医用生物力学

Objective To study the mechanical properties and biological characteristics of 3D-printed porous β-tricalcium phosphate ［β-Ca3(PO4)2, β-TCP］ scaffolds, so as to provide guidance for the design of composite scaffolds in animal experimentation. Methods Poly 1,8-octanediol citrate (POC), a kind of novel biodegradable materials, was used as the adhesive. The 3D-printed porous β-TCP scaffolds were fabricated by fused deposition modeling (FDM) technology, and Gly-Arg-Gly-Asp-Ser (GRGDS), a kind of polypeptides, was added into the scaffolds to improve the adhesive property of cells. The optical microscope and scanning electron microscope (SEM) were used to observe the micro-pore architectures of those scaffolds. The material testing machine was used to conduct compressive test on the scaffolds, and the water contact angles of the scaffolds were measured. The cell adhesion rate and proliferation rate of the scaffolds were also tested by in vitro cell experiment. The model of SD rat skull defects was repaired by the scaffolds, and the osteogenic ability in vivo was further studied. Results The GRGDS, remaining active, was evenly distributed in the composite scaffolds. The micro-pore architectures of the polypeptide modified scaffolds changed, with improvement in cell adhesion rate, while the compressive modulus, water contact angle and osteogenic ability in vivo of the scaffolds were not obviously affected. Conclusions The cell adhesion capacity of β-TCP composite scaffolds modified by polypeptide improved significantly, while the mechanical properties and hydrophilicity, osteogenic ability in vivo of the scaffolds were not affected very much. These research results provide new ideas for reconstruction of scaffolds for repairing bone defects in clinic, and a laboratory basis for further clinical application of this scaffold.

Simultaneous integrated boost on hypoxic region by means of setup errors for pancreatic cancer SBRT / 中华放射医学与防护杂志

Objective To assess the dosimetric impact on the target volumes and organs at risk ( OARs) using simultaneous integrated boost ( SIB ) for the hypoxic regions of the pancreatic cancer patients treated with stereotactic body radiotherapy ( SBRT ) , and to predict an optimal way of SIB. Methods The setup corrections guided by 100 sets of CBCT scans of 10 patients previously treated with SBRT were imported to the treatment planning system ( TPS ) to recalculate the dose to the target and OARs. Two tumor control probability ( TCP ) models were applied to calculate the TCP under various hypoxic situations. The correlations between the TCP and target dose were analyzed. Results Without setup corrections, the PTV and ITV were underdosed by 8. 9％ and 9. 2％ on average respectively relative to planed dose. With setup corrections, the mean dose to PTV and ITV coverage were 1. 6％ and 1. 3％lower than planned respectively. The mean deviations of OAR dose were between -0. 11 Gy and 0. 26 Gy for all plans. The predictive values of Dmean on hypoxic regions were 31. 4, 34. 0 and 37. 2 Gy (Niemierko model) or 31. 6, 33. 9 and 37. 2 Gy (Poisson model) when the oxygen enhancement ratios (OERs) were 1, 1. 5 and 3 respectively. Conclusions With CBCT setup corrections, the dosimetric impacts of setup errors on the target and OARs can be neglected. Significant deviations of TCP calculation were observed without accounting for tumor hypoxia. To counteract the impacts of hypoxia, the mean dose to the hypoxic regions should be at least 1. 24 times of prescribed dose.

Histomorphometric study of rabbit's maxillary sinus augmentation with various graft materials / 대한해부학회지

The purpose of this animal study is to evaluate, by histomorphometric analysis, bone regeneration in rabbit's maxillary sinuses with blood clots alone, Bio-Oss, β-tricalcium phosphate (β-TCP), and demineralized tooth dentin (DTD) grafting. Bilateral sinus augmentation procedures were performed in 18 adult male rabbits. Rectangular replaceable bony windows were made with a piezoelectric thin saw insert. In the group 1, blood clots were filled; group 2, anorganic bovine graft (Bio-Oss) was grafted; group 3, β-TCP was grafted; group 4, DTD was grafted, and covered by replaceable bony windows. Animals were sacrificed at 2, 4, and 8 weeks after surgical procedure. The augmented sinuses were evaluated by histomorphometric analysis using hematoxylin and eosin and Masson's trichrome stains. Histologically, new bone formation was revealed along the elevated sinus membrane and all graft materials. The new bone area of the group 2 was significantly greater than the group 1, and of the group 3 was significantly greater than the group 2, and of the group 4 was significantly greater than the group 3 at 8 weeks with P < 0.05. The bone marrow area of group 1 was significantly greater than other groups at 8 weeks. The DTD area was significantly lesser than Bio-Oss or β-TCP particles area at 8 weeks. This present study suggests that DTD can be effective graft materials for bone regeneration of the maxillary sinus augmentation.

Effect of oxidative stress on periprosthetic osteolysis induced by TCP wear particles in mouse calvaria and its mechanism / 中国应用生理学杂志

OBJECTIVE@#To explore the effect of oxidative stress on periprosthetic osteolysis induced by TCP wear particles in mouse calvaria and its mechanism.@*METHODS@#Thirty-six male ICR mice were randomly divided into three groups (=12):sham group, TCP wear particles (TCP) group and N-acetyl-L-cysteine (NAC) group. Aperiprosthetic osteolysis model in mouse was established by implanting 30 mg of TCP wear particles onto the surface of bilateral parietal bones following removal of the periosteum. On the 2nd day post-operation, NAC (1.0 mg/kg) was locally injected to the calvarium under the periosteum every other day for 2 weeks. Then, all the mice were sacrificed to obtain blood and the calvaria. Periprosthetic osteolysis in the mouse calvaria was observed by tartrate resistant acid phosphatase (TRAP) staining; serum levels of tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), interleukin-6 (IL-6); total anti-oxidation capacity (T-AOC) and superoxide dismutase (SOD) activity were examined by ELISA and chemical colorimetry, respectively; protein levels of glucose-regulated protein 78 (GRP78), protein kinase R-like ER kinase (PERK), phospho-PERK (p-PERK), eukaryotic initiation factor 2α (eIF2α) and phospho-eIF2α (p-eIF2α) in periprosthetic bone tissue were detected by Western blot.@*RESULTS@#Compared with sham group, serum levels of TNF-α, IL-1β and IL-6, and osteolysis area were increased obviously in TCP group (<0.05), and serum level of T-AOC and SOD activity were decreased significantly in TCP group (<0.05), GRP78 expression, the ratio of p-PERK and PERK, p-eIF2α and eIF2α in the mouse calvaria of TCP group were up-regulated markedly. Compared with TCP group, serum levels of TNF-α, IL-1β and IL-6, and osteolysis area were decreased markedly in NAC group (<0.05), serum level of T-AOC and SOD activity were increased obviously in NAC group (<0.05), and GRP78 expression, the ratio of p-PERK/PERK and p-eIF2α/eIF2α were obviously down-regulated.@*CONCLUSIONS@#Inhibition of oxidative stress can prevent periprosthetic osteolysis induced by TCP wear particles, which may be mediated by inactivation of PERK/eIF2α signaling pathway.

TCP wear particles causes injury of periprosthetic osteocytes in the mouse calvaria / 中国应用生理学杂志

OBJECTIVE@#To study whether tricalcium phosphate(TCP) wear particles cause injuries of periprosthetic osteocytes in the mouse calvaria, and to explain its molecular mechanism.@*METHODS@#Thirty six-week(ICR)male mice were randomly divided into sham group, model (TCP) group and 3-methyladenine (3-MA) group. A murine calvarial model of osteolysis was established by 30 mg of TCP wear particles implantation over the periosteum around the middle suture of calvaria in mice. On the second postoperative day, the autophagy specific inhibitor 3-MA (1.0 mg/kg) was subcutaneously injected to the calvaria in the 3-MA-treated mice every other day. After 2 weeks, blood and the calvaria were obtained. Micro-CT was used to detect bone mineral density(BMD), bone volume fraction (BVF) and porosity number. HE staining and flow cytometry were performed to analyze the viability and apoptosis of periprosthetic osteocytes. The serum levels of dentin matrix protein 1(DMP-1) and sclerostin (SOST) were determined by ELISA. The proteins expressions of DMP-1, SOST, Beclin-1 and microtuble-associated protein 1 light chain 3 (LC-3) were detected by Western blot in the calvaria osteocytes.@*RESULTS@#Compared with the sham group, the mice in the TCP group showed that a significant decrease in the viability of periprosthetic osteocytes, but obvious increases in number of osteocytes death and osteocytes apoptosis (<0.05), and in serum level and protein expression of SOST; significant decreases in serum level and protein expression of DMP-1 (<0.05), and remarkable up-regulation of autophagy-related factors beclin-1 and the conversion of LC3-Ⅱ from LC3-I in the calvaria osteocytes. Compared with TCP group, the mice in the 3-MA group showed that injuries of calvaria osteocytes were obviously aggravated, and osteocytes apoptosis was significantly increased (<0.05).@*CONCLUSIONS@#TCP wear particles can cause injuries of periprosthetic osteocytes via activation of apoptosis and autophagy, which promotes osteolysis around the prosthesis osteolysis and joint aseptic loosening.

Modelo experimental para el estudio de la reconstrucción mandibular: opciones en conejos Oryctolagus cuniculus / Experimental model for the study of mandibular reconstruction: options in rabbits Oryctolagus cuniculus

El propósito de este estudio fue de evaluar la técnica quirúrgica propuesta para estudios de resección y reconstrucción mandibular en modelos experimentales en conejos. Se utilizaron 7 conejos neozelandeses (Orictolagus cuniculus), en los cuales se realizó la resección del cuerpo mandibular izquierdo, una vez asegurada la movilidad de los segmentos, se reconstruyó con placa de osteosíntesis de titanio de 1,5 mm y tornillos monocorticales de 5 mm, en la zona resecada se fijó un bloque de beta fosfato tricálcico y estabilizado con tornbillo de 1,2 mm. Se sacrificaron los animales a los 2 meses. Todos los animales sobrevivieron al procedimiento y se pudo llevar a cabo la resección y reconstrucción en todos ellos. No se presentaron signos ni síntomas de infección en el sitio quirúrgico mientras duró el experimento. El tiempo promedio de cirugía fue de 68 minutos. El peso promedio de los animales fue de 3925 g, la pérdida promedio de peso fue de 2,03 %. No se realizó eutanasia de ningún animal por motivos de sufrimiento. Al examen macroscópico de las muestras extraídas se observó la presencia de todos los elementos de osteosíntesis en posición, así como continuidad de la estructura ósea casi en su totalidad en la superficie . La utilización de conejos en modelos de reconstrucción maxilofacial es un modelo probado debido a la similitud de los procesos reparativos, su facilidad de manipulación y cuidados. El modelo propuesto representa una alternativa más cercana a los procesos reconstructivos en cirugía resectiva maxilofacial, debido a que somete los injertos a las fuerzas propias de la masticación y de la función orofacial.

The purpose of this study was to evaluate the surgical technique proposed for studies of resection and mandibular reconstruction in experimental models in rabbits. Seven rabbits (Orictolagus cuniculus) were used, in which the left mandibular body was resected, once the mobility of the segments was assured, reconstructed with 1.5 mm titanium osteosynthesis plate and monocortical screws of 5 mm, in the resected area a block of beta-tricalcium phosphate was stabilized and stabilized with tornbillo of 1.2 mm. The animals were sacrificed at 2 months. All animals survived the procedure, and resection and reconstruction were performed in all of them. There were no signs or symptoms of infection at the surgical site during the experiment. The average length of surgery was 68 minutes. The average weight of the animals was 3.925 g, the average weight loss was 2.03 %. No animal was euthanized for reasons of suffering. Macroscopic examination of the extracted samples showed the presence of all elements of osteosynthesis in position, as well as continuity of the bone structure almost entirely on the surface. The use of rabbits in models of maxillofacial reconstruction is a proven model due to the similarity of the reparative processes, their ease of manipulation and care. Our proposed model represents a closer alternative to the reconstructive processes in maxillofacial resective surgery, because it subjects the grafts to the forces of chewing and orofacial function.

Instrumento para evaluar la intención de niños mexicanos para consumir bebidas alcohólicas desde la Teoría de la Conducta Planeada / Instrument to evaluate the intention of Mexican children to consume alcoholic beverages based on the Theory of Planned Behavior

Resumen El incremento en el consumo de alcohol y la disminución en la edad de inicio requieren del desarrollo de propuestas preventivas dirigidas a población en edad más temprana, sustentadas teórica y empíricamente, como la Teoría de la Conducta Planeada (TCP). Para ello se debe conocer la intención que tiene el sujeto de consumir esta sustancia, por lo que se vuelve necesario evaluar sus creencias de comportamiento, normativas y de control sobre la conducta de interés. Un medio para evaluar dichas creencias lo constituyen las escalas de medición. El objetivo de este trabajo fue describir el proceso que se siguió para construir un instrumento, válido y confiable, que mide la intención de los niños de consumir bebidas con alcohol desde la Teoría de la Conducta Planeada. A diferencia de los estudios reportados desde esta teoría con adultos, no se encontró diferencia entre las creencias normativas y la importancia que se les da. En cuanto al control conductual percibido, los niños no identifican barreras para el consumo en el cuestionario, solo facilitadores. Esto puede estar relacionado con que en esta edad, es una conducta experimental. Por lo tanto la forma de calificar el instrumento para obtener la puntación en intención tuvo que modificarse.

Abstract The increase in alcohol consumption and the decrease in the age of onset requires the development of preventive proposals aimed at younger age population, theoretically and empirically supported. Theory of Planned Behavior (TCP) has this base, for it must know the intention of the subject of doing, being necessary to assess their behavioral beliefs, normative and control on the behavior of interest. A means of assessing such beliefs is constituted by the measurement scales. The aim of this study was to describe the process followed to build a valid and reliable instrument, which measures the intention of children to consume alcoholic beverages from the The-ory of Planned Behavior. Unlike the reported studies from this theory with adults, there were no differences between normative beliefs and the importance they are given. In terms of perceived behavioral control, children did not identify barriers to consumption in the questionnaire, only facilitators. This may be related to the fact that at this age, this is an experimental behaviour, so the way to qualify the instrument to get a score in intention had to be modified.

The Influences of Different Ratios of Biphasic Calcium Phosphate and Collagen Augmentation on Posterior Lumbar Spinal Fusion in Rat Model

PURPOSE: To determine the influence of different ratios of hydroxyapatite (HA)/beta tricalcium phosphate (β-TCP) and collagen augmentation for posterior lumbar fusion in a rat model. MATERIALS AND METHODS: We generated a posterior lumbar fusion model in 50 rats and divided it into five groups of equal number as follows; 1) autologous bone graft as group A, 2) 70% HA+30% β-TCP as group B, 3) 70% HA+30% β-TCP+collagen as group C, 4) 30% HA+70% β-TCP as group D, and 5) 30% HA+70% β-TCP+collagen as group E. Rats were euthanized at 12 weeks after surgery and fusion was assessed by manual palpation, quantitative analysis using microCT and histology. RESULTS: The score of manual palpation was significantly higher in group C than group E (3.1±1.1 vs. 1.8±0.8, p=0.033). However, in terms of microCT analysis, group D showed significantly higher scores than group B (5.5±0.8 vs. 3.1±1.1, p=0.021). According to quantitative volumetric analysis, 30% HA+70% β-TCP groups (group D and E) showed significantly reduced fusion mass at 12 weeks after surgery (123±14.2, 117±46.3 vs. 151±27.3, p=0.008, 0.003, respectively). Collagen augmentation groups revealed superior results in terms of both microCT score and histologic grade. CONCLUSION: A 7:3 HA/β-TCP ratio with collagen augmentation rather than a 3:7 HA/β-TCP ratio could be a more favorable graft substitute for lumbar spinal fusion. There was positive role of collagen as an adjunct for spinal bone fusion process.