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In this study, the flow injection (FI) technology combined with the unique step wise multiple ions monitoring scanning (step-wise MIM) mode of Qtrap-MS was first established for the identification and discrimination of eight Murraya species. It only takes 5 min for each sample to detect approximate 600 compounds. The characteristic MS chromatograms of eight Murraya plants were analyzed by Analyst and SIMCA-P. The results of PCA showed that sect. Murraya and sect. Bergera were clearly divided into two categories, suggesting that there is difference in the chemical compositions between these two groups. Further detail analysis of the MS data could realize the preliminary structure elucidation of the component types contained in different plants. The main components in M. exotica and M. alata are coumarins, and polymethoxyflavones are rich in M. paniculata, while carbazole alkaloids are the major ones in sect. Bergera plants. The results are consistent with our previous comprehensive analysis of the chemical components of Murraya species. In conclusion, our research confirmed that FI-Qtrap-MS technology can be used for rapid identification and differentiation of similar plant species, providing reference for chemical taxonomy and a new method for the quality evaluation of medicinal materials.
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@#In 2022, many excellent clinical studies emerged in the field of cardiovascular surgery. Selecting papers published in The New England Journal of Medicine and other top medicine and cardiology journals, this review focused on the research progress on 7 topics in the field of cardiovascular surgery: coronary artery surgery, vascular surgery, valvular surgery, structural heart disease, congenital heart disease, heart transplantation, perioperative management, and special population.
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There are two source plants for the traditional Chinese medicine Murrayae Folium et Cacumen (MFC) in Chinese Pharmacopoeia, i.e. Murraya exotica L. and M. paniculata (L.) Jack. Herein, a chemical comparison of M. exotica and M. paniculata by high performance liquid chromatography (HPLC) fingerprint analysis coupled with chemometrics and network pharmacology was performed. The main peaks in the fingerprints were identified by liquid chromatography coupled with ion trap/time-of-flight mass spectrometry (LC-IT-TOF-MS) and authenticated by references. The chemometrics results showed that the HPLC fingerprints of these two species were clearly divided into two categories using hierarchical cluster analysis (HCA) and principal component analysis (PCA), and a total of 13 significantly differentiated markers were screened out by orthogonal partial least squares-discriminant analysis (OPLS-DA). However, the following network pharmacology analysis showed that these discriminated markers were found to act via many common targets and metabolic pathways, indicating the possibly similar pharmacological effects and mechanisms for M. exotica and M. paniculata. The above results provide valuable evidence for the equivalent use of these two plants in clinical settings. Moreover, the chromatographic fingerprint analysis coupled with chemometrics and network pharmacology supplies an efficient approach for the comparative analysis of multi-source TCMs like MFC.
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BACKGROUND@#Anterior thalamic nuclei (ATN) deep brain stimulation (DBS) is an effective method of controlling epilepsy, especially temporal lobe epilepsy. Mossy fiber sprouting (MFS) plays an indispensable role in the pathogenesis and progression of epilepsy, but the effect of ATN-DBS on MFS in the chronic stage of epilepsy and the potential underlying mechanisms are unknown. This study aimed to investigate the effect of ATN-DBS on MFS, as well as potential signaling pathways by a kainic acid (KA)-induced epileptic model.@*METHODS@#Twenty-four rhesus monkeys were randomly assigned to control, epilepsy (EP), EP-sham-DBS, and EP-DBS groups. KA was injected to establish the chronic epileptic model. The left ATN was implanted with a DBS lead and stimulated for 8 weeks. Enzyme-linked immunosorbent assay, Western blotting, and immunofluorescence staining were used to evaluate MFS and levels of potential molecular mediators in the hippocampus. One-way analysis of variance, followed by the Tukey post hoc correction, was used to analyze the statistical significance of differences among multiple groups.@*RESULTS@#ATN-DBS is found to significantly reduce seizure frequency in the chronic stage of epilepsy. The number of ectopic granule cells was reduced in monkeys that received ATN stimulation (P < 0.0001). Levels of 3',5'-cyclic adenosine monophosphate (cAMP) and protein kinase A (PKA) in the hippocampus, together with Akt phosphorylation, were noticeably reduced in monkeys that received ATN stimulation (P = 0.0030 and P = 0.0001, respectively). ATN-DBS also significantly reduced MFS scores in the hippocampal dentate gyrus and CA3 sub-regions (all P < 0.0001).@*CONCLUSION@#ATN-DBS is shown to down-regulate the cAMP/PKA signaling pathway and Akt phosphorylation and to reduce the number of ectopic granule cells, which may be associated with the reduced MFS in chronic epilepsy. The study provides further insights into the mechanism by which ATN-DBS reduces epileptic seizures.
Subject(s)
Humans , Adenosine Monophosphate , Anterior Thalamic Nuclei , Cyclic AMP-Dependent Protein Kinases , Deep Brain Stimulation , Epilepsy/therapy , Epilepsy, Temporal Lobe/therapy , Hippocampus , Mossy Fibers, Hippocampal , Signal TransductionABSTRACT
Rotator cuff tears are one of the three most prevalent musculoskeletal disorders, with the supraspinatus tendon as the most common lesion site. It may lead to chronic shoulder pain, weakness and limited joint motion, and eventually to secondary degeneration of the shoulder. As traditional biomechanical experiments are limited by measurement techniques and ethical issues, it is almost impossible to clarify the stress distributions at the rotator cuff under physiological and pathological conditions. Recently, advances in computer science, software development and image processing have rapidly improved finite element models of shoulder joint which promote the researches into pathogenesis of rotator cuff tears and their surgical techniques, making finite element analysis an indispensable means in the biomechanic research of rotator cuff. This paper reviews the recent literature available in China and abroad to expound on the element models of shoulder joint applied in the researches into pathogenesis and surgery of rotator cuff tear.
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Objective:To evaluate whether posterior cruciate ligament (PCL) avulsion fracture was correlated with intercondylar notch and tibial slope.Methods:A total of 48 patients with PCL avulsion fracture were compared with 48 age- and sex-matched healthy controls without PCL avulsion fracture from January 2012 to October 2018 in our hospital. There were 25 males and 23 females with an average age of 54.35±14.06 years (range 27-82 years) in PCL avulsion fracture group. MRI of the knee joint were acquired in the sagittal, coronal, and axial sequences. The measurements included intercondylar notch's angle, width, and height, medial/lateral condylar widths, condylar width, medial/lateral posterior tibial slopes and coronal tibial slope. Notch shape index and notch width index were also calculated to adjust for size variations. The predictive accuracy of Risk factors were analyzed using the area under the receiver operating characteristic curve (AUC). The differences of morphological measurements between the two groups were compared. The morphological measurements with statistical significance were included for further multivariate analysis. Risk factors of PCL avulsion fracture were determined by binary logistic regression analysis. The inter- and intra-observer reproducibility of the measurements was determined by the intraclass correlation coefficients (ICC).Results:Except for coronal intercondylar notch height (0.709), medial posterior tibial slope (0.699) and lateral posterior tibial slope (0.705), the other intra-observer ICC ranged from 0.802 to 0.980, which indicated that the parameters had desirable reproducibility. Similarly, except for coronal intercondylar notch height (0.700), the other intra-observer ICC ranged from 0.778 to 0.971. Parameters of patients with PCL avulsion fracture, including the axial notch angle (52.56°±6.56°), coronal notch angle (54.81°±7.29°), axial intercondylar notch width (19.62±2.32 mm), axial notch shape index (0.68±0.08) and medial posterior tibial slope (8.27°±3.53°), were all significantly larger than those of the control group. The binary logistic regression analysis showed that the coronal notch angle ( β=0.102, OR=1.108, P=0.030) and medial posterior tibial slope ( β=0.151, OR=1.163, P=0.046) were the risk factors or PCL avulsion fracture. The AUC for coronal notch angle (0.678) and medial posterior tibial slope (0.631) exhibited good predictive power for the occurrence of PCL avulsion fracture. Conclusion:The larger coronal notch angle and medial posterior tibial slope were positively correlated with the incidence of PCL avulsion fracture.
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Objective@#To investigate the mid-term efficacy of extracapsular arthroscopic surgery for refractory tennis elbow and explore prognostic factors.@*Methods@#A retrospective study of 38 patients suffered from refractory tennis elbow and underwent extracapsular arthroscopic surgery performed by the same group of doctors during March 2012 to January 2016 at Institute of Sports Medicine, Peking University Third Hospital. There were 15 males and 23 females with age of 44.2 years(range: 32-59 years). Fifteen cases on the left and 23 cases on the right. Visual analogue scale(VAS), Mayo elbow performance score and Disability of Army, Shoulder and Hand (DASH) score were collected preoperatively and postoperatively, and compared by paired-t test. Independent sample t test, χ2 test, multivariate logistic regression were used to analyze the relationship between scores and various potential influencing factors.@*Results@#All 38 patients were followed up for 24 months. There was no complication such as infection or nerve injury recorded. VAS decreased from 7.0(1.2) (M(QR)) preoperative to 0(1) (Z=-5.40, P=0.00), Mayo increased from 55(26) to 100(0) (Z=-5.38, P=0.00),DASH decreased from 56.7(27.3) to 0.8(5.8)(Z=-5.37,P=0.00). The Mayo elbow performance score was excellent in 36 cases (94.7%) and good in 2 cases (5.3%). Women was significantly associated with poor prognosis.@*Conclusions@#The mid-term effect of extracapsular arthroscopic treatment of refractory tennis elbow is satisfactory with few postoperative complications. Women was associated with poor prognosis.
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Scoliosis is a complex spinal three-dimensional malformation with complicated pathogenesis, often associated with complications as thoracic deformity and shoulder imbalance. Because the acquisition of specimen or animal models are difficult, the biomechanical study of scoliosis is limited. In recent years, along with the development of the computer technology, software and image, the technology of establishing a finite element model of human spine is maturing and it has been providing strong support for the research of pathogenesis of scoliosis, the design and application of brace, and the selection of surgical methods. The finite element model method is gradually becoming an important tool in the biomechanical study of scoliosis. Establishing a high quality finite element model is the basis of analysis and future study. However, the finite element modeling process can be complex and modeling methods are greatly varied. Choosing the appropriate modeling method according to research objectives has become researchers' primary task. In this paper, the author reviews the national and international literature in recent years and concludes the finite element modeling methods in scoliosis, including data acquisition, establishment of the geometric model, the material properties, parameters setting, the validity of the finite element model validation and so on.
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Humans , Biomechanical Phenomena , Computer Simulation , Finite Element Analysis , Scoliosis , General Surgery , Spine , PathologyABSTRACT
Isorhapontigenin (ISO) is suggested to have many different kinds of pharmacology activities, such as anti-inflammatory effect, anti-oxidation effect and anti-cancer effect. This paper mainly discussed the transport mechanism of ISO in Caco-2 cell models. The concentration of ISO was determined by UPLC method with PDA detector at 310 nm, and then the apparent permeability coefficient Papp was calculated. The cytotoxic of different concentrations of ISO was investigated on Caco-2 cells to determine the concentration of drug administration. The effects of ISO concentration, time, temperature and transporter inhibitors on the transport of ISO were investigated. The test results showed that, ISO didn't have significant cytotoxicity at 10-60 μmol•L ⁻¹ in 14 hours. The transportation of ISO on Caco-2 cells was related to the concentration to a certain extent. Papp of ISO was higher than 10×10-6 cm•s ⁻¹ and ISO was absorbed easily by Caco-2 cells. The transport volume of ISO at BL side reached maximum at 3 h and was slightly decreased at 6 h. Papp (AP-BL) and Papp(BL-AP) at 4 ℃ were lower than those at 37 ℃. Papp (AP-BL) of ISO was significantly increased after adding P-gp inhibitor verapamil and Papp (BL-AP) of ISO was significantly decreased after adding MRP-2 inhibitor (probenecid or MK-571). The results suggested that transport mode of ISO was mainly passive diffusion in Caco-2 cell models, and P-gp and MRP may be involved in the transport of ISO.
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Objective:To explore the influence of the veneering porcelain thickness on the compressive strength of zirconia all-ceramic crown.Methods:25 zirconia basement crowns with the thickness of 0.5 mm were made by CAD-CAMsystem,and then were divided into 5 groups randomly with the veneering porcelain thickness of 0.5(A),1.0(B),1.5(C),2.0(D)and 2.5 mm(E)respectively. The compressive strength of the samples was measured by a testing machine.Statistical analysis was conducted by SPSS13.0 software. The microstructure of the fractured bonding interface of the specimens was observed by scanning electron microscope(SEM).Results:The compressive strength in group A,B,C,D and E were:(1 279.96 ±42.85)N,(2 235.44 ±50.14)N,(2 216.38 ±48.97)N, (2 169.22 ±60.40)N and (2 028.70 ±47.37)N respectively(A or E vs B,C or D,P 0.05;C vs D,P >0.05).SEMobservation found that in group A and E the bonding interface was uneven and loose,the cracks and spores in veneering porcelain appeared more and larger,and had a more intensive distribution.Conclusion:When the veneering porce-lain is too thick or too thin,the compressive strength of zirconia all-ceramic crown decreases,the thickness of the veneering porcelain should be controled in an appropriate range.
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Objective:To compare the titanium-porcelain bonding strength between CAD/CAM and cast pure titanium.Methods:Pure titanium samples were prepaired by CAD/CAMand casting respectively and fused with porcelain.The bond strength between tita-nium and porcelain of the samples was measured with three-point test.The titanium-porcelain interface was investigated under scanning electronic microscope(SEM).Results:The bond strength of CAD/CAMpure titanium to porcelain was (35.95 ±3.74)MPa and cast pure titanium to porcelain was (28.37 ±1 .98)MPa(P <0.05).SEMobservation showed that there was thin transition layer between titanium substrate and ceramic in CAD/CAM bond interface,titanium and porcelain combined closely,no obvious pores.However, there was thicker transition layer and small pore in cast pure titanium to porcelain bonding interface.Conclusion:The bonding strength of porcelain to CAD/CAMpure titanium is greater than that of porcelain to casting pure titanium.
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<p><b>OBJECTIVE</b>To develop a child craniofacial three-dimensional (3D) finite element model (FEM) with sutures defined alone.</p><p><b>METHODS</b>The CT data for this study was developed from sequential computed tomography scan images taken at 0.625 mm intervals of an 8 years children skull. Data set was imported into Mimics 10.0 and processed with Geomagic 9.0, and exported as initial graphics exchange specification(IGES) files. The IGES files were then imported into Ansys 13.0 to set up two FEM with or without the median palatine suture being opened. The FEM contained nine craniofacial sutures and eight teeth which were defined alone.For simulating orthopedic maxillary protraction, three forces (F1-F2) were loaded on FEM.F1(1 N) was loaded at 1 cm above the geison. F2(1 N) was loaded at articular fossa of temporal bone. F3(2 N) was directed anteriorly and paralleled with occlusal plane near the canine. The stress distribution and the values distributed in each point gained in the two models were compared.</p><p><b>RESULTS</b>Two craniofacial 3D FEM of the child were developed with the median palatine suture opened or not .With median palatine suture being opened or not, the two models showed the similar von Mises stresses (VMS). The distribution of the VMS was in the bridge of the nose and dextro-ala nasi.When the median palatine suture was opened, the max VMS value was 18916.00×10(-4) MPa which appeared in the nose point and the min VMS value was 1.61×10(-4) MPa which appeared in the maxillary central incisor point. At the same time, the max stress value at the direction Y was -3985.30×10(-4) MPa and appeared in the frontomaxillary suture point, and the min Y value was 0.08×10(-4) MPa which appeared in the maxillary central incisor point. When the median palatine suture was not opened, the max VMS value was 19 244.00×10(-4) MPa and appeared in the nose point. The min VMS value was 1.62×10(-4) MPa and appeared in the maxillary central incisor point. At the same time, the max stress value at the direction Y was -4258.20×10(-4) MPa and appeared in the frontomaxillary suture point, and the min Y value was 0.08×10(-4) MPa which appeared in the maxillary central incisor point.</p><p><b>CONCLUSIONS</b>To define the sutures as entities alone contributed to develop child craniofacial 3D FEM which consist nine sutures. There was tiny difference in stress distribution in both the VMS and in Y direction with the median palatine suture being opened or not.</p>
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Child , Humans , Male , Cephalometry , Methods , Computer Simulation , Cranial Sutures , Physiology , Dental Stress Analysis , Methods , Finite Element Analysis , Imaging, Three-Dimensional , Models, Biological , Skull , Diagnostic Imaging , Stress, Mechanical , Tomography, Spiral ComputedABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect of potential spinal growth on the posterior-only spinal instrumentation of adolescent idiopathic scoliosis (AIS).</p><p><b>METHODS</b>From June 2003 to October 2007, 40 patients received posterior-only spinal instrumentation. Group of open triradiate cartilage (Group A) included 16 female AIS patients with mean age of 11.8, and group of closed triradiate cartilages (Group B) covered 24 female AIS patients with mean age of 13.7. The mean preoperative Cobb angles of Group A and B were 53.3° and 49.6° respectively, and the mean kyphosis in the sagittal plane was 27.7° and 27.8° respectively.</p><p><b>RESULTS</b>The post-operative Cobb angles were 22.2° (Group A) vs. 20.7° (Group B) (P = 0.34) with correction rate of 58.3% (Group A) vs. 57.7% (Group B) (P = 0.83). The mean Cobb angles at final follow-up were 24.8° (Group A) vs. 21.1° (Group B) (P = 0.05) with the correction loss of 5.3% (Group A) vs. 1.0% (Group B) (P = 0.01). In the sagittal plane, the average post-operative kyphosis was 22.5° (Group A) vs. 23.9° (Group B) (P = 0.49) with correction of 5.2° (Group A) vs. 3.9°(Group B) (P = 0.63). The mean kyphosis at final follow-up was 20.8°(Group A) vs. 24.7°(Group B) (P = 0.04) with the correction loss of -1.7° (Group A) vs. 0.8°(Group B) (P = 0.01). Group A showed obvious correction loss in the coronal plane and decrease of kyphosis in the sagittal plane. Adding on phenomenon was found in 2 cases with Lenke type I with selected fusion in Group A, but not in Group B.</p><p><b>CONCLUSIONS</b>Although similar post-operative correction is found in AIS patients with OTRC or CTRC, the loss of correction and "adding on phenomenon" are more likely to happen in patients with OTRC.</p>