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BACKGROUND:Scaffold materials serve as platforms that provide space and structure,playing a crucial role in the regeneration of cartilage tissue.Scholars from around the world are exploring different approaches to fabricate more ideal scaffold materials. OBJECTIVE:To review the design principles and preparation methods of cartilage scaffolds,and to further explore the advantages and limitations of various preparation methods. METHODS:Literature searches were conducted on the databases of CNKI,WanFang Data,PubMed,and FMRS from 1998 to 2023.The search terms were"cartilage repair,cartilage tissue engineering,cartilage scaffold materials,preparation"in Chinese and English.A total of 57 articles were ultimately reviewed. RESULTS AND CONCLUSION:(1)The articular cartilage has a unique structure and limited self-repair capacity after injury.Even if self-repair occurs,the newly formed cartilage is typically fibrocartilage,which is far inferior to normal articular cartilage in terms of structure and mechanical properties.It is difficult to maintain normal function and often leads to degenerative changes.Currently,the design and fabrication of scaffold materials for cartilage repair need to consider the following aspects:biocompatibility and biodegradability,suitable pore structure and porosity,appropriate mechanical properties,and bioactivity.(2)Research on the preparation of cartilage scaffolds has made significant progress,continuously introducing new preparation methods and optimization strategies.These methods have their advantages and disadvantages,providing more possibilities for customized preparation and functional design of cartilage scaffolds according to specific requirements.
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BACKGROUND:Bone formation is the process by which osteoblasts synthesize and secrete osteoid and promote its mineralization,which generally involves mechanical signal transduction.Osteoblasts are primarily regulated by mechanical factors such as gravity,compressive stress,tensile stress,fluid shear stress,and hydrostatic pressure in vivo,and different mechanical stimuli modulate the proliferation,differentiation,and apoptosis of osteoblasts through various mechanisms,including hormones,cytoskeletal proteins,and microRNAs.By clarifying the effects of biomechanical forces on osteoblasts,it provides ideas and a reference basis for the treatment of osteometabolic diseases involving osteoblasts. OBJECTIVE:To review the effects of different biomechanical forces on the biological characteristics of osteoblasts. METHODS:We conducted a literature search using PubMed,Web of Science,FMRS,CNKI,and WanFang databases for relevant publications published from 2000 to 2023,covering basic research and tissue engineering studies related to the effects of biomechanical forces on osteoblasts.Ultimately,a total of 70 articles were reviewed. RESULTS AND CONCLUSION:Different biomechanical forces have an impact on the biological characteristics of osteoblasts,including proliferation,differentiation,and apoptosis,and these effects are dependent on the intensity and duration of the applied force.Specifically,the effects are as follows:(1)Under microgravity conditions,osteoblast proliferation and differentiation are inhibited,resulting in a decrease in bone density and the development of osteoporosis.(2)Compared to microgravity,hypergravity has a promoting effect on osteoblast proliferation.(3)The effects of compressive stress on osteoblasts are dependent on the loading intensity and time.Appropriate compressive stress can promote osteoblast proliferation and differentiation,which is beneficial for bone tissue formation and repair,while excessive compressive stress can cause osteoblast apoptosis and bone tissue destruction.(4)The biological effects of different types of tensile stress on osteoblasts differ.Studies have shown that a strain rate within the range of 0-12%has a promoting effect on osteoblast proliferation.(5)Fluid shear stress can promote osteoblast proliferation and differentiation and enhance the bone-inducing effect of biomaterials.(6)Static hydrostatic pressure can affect the biological behavior of osteoblasts,including proliferation,differentiation,and apoptosis,and these effects are closely related to the time and intensity of the pressure.Understanding the effects of different biomechanical forces on osteoblasts is of great significance for a deeper understanding of bone growth and maintenance mechanisms.
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Objective@#To explore the characteristics of pain sensitivity of autism spectrum disorder (ASD), and to provide reference for clinical comprehensive intervention of ASD.@*Methods@#A case-control study was conducted to investigate the characteristics of pain sensitivity in 142 ASD children and 142 normal children using the items related to pain sensitivity in the Autism Treatment Evaluation Checklist (ATEC). In addition, two recognized ASD model mice (BTBR mice and model mice induced by VPA) were selected as experimental group. The thermal pain threshold and mechanical pain threshold of BTBR mice were measured by electroshock seizure threshold and Von Frey filament test, and the differences of pain characteristics between BTBR mice and control mice were compared, the thermal pain threshold of model mice induced by VPA (VPA rats) was measured by electroshock seizure threshold, and the differences between BTBR mice and control mice (Con) were compared.@*Results@#There was significant difference in pain sensitivity between ASD group and control group (χ 2=0.81,P<0.05), and the sensitivity of ASD children to pain was significantly lower than that of normal control children. The pain sensitivity of BTBR mice and C57BL/6 mice on the 42 nd day after birth was measured. The T-test analysis showed that the time taken for BTBR and C57BL/6 mice to retract their feet on the 42 nd day after birth (3.62±0.38,3.02±0.33)s (t=3.28,P<0.01), and the mechanical pain threshold (9.75±3.58,0.55±0.93)s (t=7.44,P<0.01). The detection of thermal stinging pain in VPA rats and con rats on the 9 th, 11 th, 13 th and 15 th day after birth was detected. The results of t test were as follows:P9(11.34±1.38,9.81±1.64)g, P11(11.37±1.98,9.36±1.11)g, P13(11.53±1.38,9.51±1.01)g and P15(12.05±2.91,8.74±1.60)g (t=-2.79,-2.25,3.95,3.95,P<0.05).@*Conclusion@#Compared with normal control children, ASD children show insensitivity to pain which is further supported by two types of animal models for ASD.
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Background@#We hypothesized that specific amino acids or acylcarnitines would have benefits for the differential diagnosis of diabetes. Thus, a targeted metabolomics for amino acids and acylcarnitines in patients with diabetes and its complications was carried out. @*Methods@#A cohort of 54 normal individuals and 156 patients with type 2 diabetes mellitus and/or diabetic complications enrolled from the First Affiliated Hospital of Jinzhou Medical University was studied. The subjects were divided into five main groups: normal individuals, impaired fasting glucose, overt diabetes, diabetic microvascular complications, and diabetic peripheral vascular disease. The technique of tandem mass spectrometry was applied to obtain the plasma metabolite profiles. Metabolomics multivariate statistics were applied for the metabolic data analysis and the differential metabolites determination. @*Results@#A total of 10 cross-comparisons within diabetes and its complications were designed to explore the differential metabolites. The results demonstrated that eight comparisons existed and yielded significant metabolic differences. A total number of 24 differential metabolites were determined from six selected comparisons, including up-regulated amino acids, down-regulated medium-chain and long-chain acylcarnitines. Altered differential metabolites provided six panels of biomarkers, which were helpful in distinguishing diabetic patients. @*Conclusion@#Our results demonstrated that the biomarker panels consisted of specific amino acids and acylcarnitines which could reflect the metabolic variations among the different stages of diabetes and might be useful for the differential diagnosis of prediabetes, overt diabetes and diabetic complications.
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Background@#We hypothesized that specific amino acids or acylcarnitines would have benefits for the differential diagnosis of diabetes. Thus, a targeted metabolomics for amino acids and acylcarnitines in patients with diabetes and its complications was carried out. @*Methods@#A cohort of 54 normal individuals and 156 patients with type 2 diabetes mellitus and/or diabetic complications enrolled from the First Affiliated Hospital of Jinzhou Medical University was studied. The subjects were divided into five main groups: normal individuals, impaired fasting glucose, overt diabetes, diabetic microvascular complications, and diabetic peripheral vascular disease. The technique of tandem mass spectrometry was applied to obtain the plasma metabolite profiles. Metabolomics multivariate statistics were applied for the metabolic data analysis and the differential metabolites determination. @*Results@#A total of 10 cross-comparisons within diabetes and its complications were designed to explore the differential metabolites. The results demonstrated that eight comparisons existed and yielded significant metabolic differences. A total number of 24 differential metabolites were determined from six selected comparisons, including up-regulated amino acids, down-regulated medium-chain and long-chain acylcarnitines. Altered differential metabolites provided six panels of biomarkers, which were helpful in distinguishing diabetic patients. @*Conclusion@#Our results demonstrated that the biomarker panels consisted of specific amino acids and acylcarnitines which could reflect the metabolic variations among the different stages of diabetes and might be useful for the differential diagnosis of prediabetes, overt diabetes and diabetic complications.
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The paper briefly introduces the definition, characteristics of MOOC and its development both in China and abroad, ana-lyzes the relation between medical college and university library and MOOC.It points out that libraries should provide embedded course services based on MOOC, establish MOOC Information Commons ( IC) , develop MOOC specialized database and enhance capability of the librarians in order to develop MOOC from various aspects and continuously promote information service innovation.
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Objective To explore the clinical features of vestibular paroxysmia (VP).Methods The clinical features of 51 patients with VP from January 2009 to April 2011 were analyzed retrospectively.The treatment effectiveness of antiepileptics was evaluated.Results The ratio of male to female was 1 ∶ 1.55 in the 51 patients with VP and the course of disease was 10 days to 20 years.In 46 patients (90.2%) the attacks occurred at rest,whereas 37 patients (72.5%) were precipitated by a head turn or a body turn.Three minutes hyperventilation-induced vertigo was found in 13 patients (25.5%) and Fukuda test was positive in 15 patients (29.4%).Forty patients (78.4%) were abnormal in brainstem auditory evoked potentials (BAEP) and the interpeak latency of wave Ⅰ-Ⅲ was prolonged than 2.2 ms in 26 patients (51.0%).There were 47 ears had neurovascular cross-compression (NVCC),which were unilateral in 37 patients and bilateral in 5 patients,with type Ⅰ in 23 ears(48.9%),type Ⅱ in 5 ears(10.6%),type Ⅲ in 17 ears(36.2%) and type Ⅳ in 2 ears(4.3%).Three month-treatment led to a significant reduction in the attack frequency(3 (2,7) per month vs 15 (9,30) per month,Z =-6.156,P < 0.01),in the attack duration(2(1,4) s vs 12(6,20) s,Z =-6.066,P <0.01),and a reduction in the visual analogue scale of vertigo (1.86 ±0.57 vs 5.83 ± 1.12,t =1.984,P < 0.01).Conclusions Briefvertigoattacksatrestis the character of VP.Three minutes hyperventilation-induced vertigo is helpful for the diagnosis of VP.The prolongation of the interpeak latency of wave Ⅰ-Ⅲ in BAEP is the character of VP.NVCC widely existed in the patients with VP and types Ⅰ and type Ⅲ was more common.Using antiepileptics,a better treatment effectiveness can be obtained.
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Objective To explore the clinical features and repositioning maneuver effects of benign paroxysmal positional vertigo ( BPPV ).Method The clinical features of 326 patients with BPPV from August 2009 to July 2011 were analyzed retrospectively.Different types of BPPV were compared.Results BPPV was more common in female and the peak period of onset was between the ages of 50 and 60.The average latency of vertigo attack was ( 1.52 ± 1.22) s and 43 patients ( 13.2% ) had no obvious latency.The median duration of vertigo attack was 10 s,with less than 60 s in 312 patients (95.7%) and between 60—180 s in 13 patients (4.0%).The latency of vertigo attack of posterior semicircular canal-BPPV ( ( 1.74 ± 1.21 ) s) was longer than that of horizontal semicircular canal-BPPV ( ( 0.96 ± 1.06 ) s,t =5.546,P <0.01 ).But there were no differences in the gender,the course of disease and the duration of vertigo attack.The patients with posterior semicircular canal-cupulolithiasis were younger than those with posterior semicircular canal-canalithiasis.The duration of vertigo attack of posterior semicircular canalcupulolithiasis was longer than that of posterior semicircular canal-canalithiasis.The latency and the duration of vertigo attack of horizontal semicircular canal-cupulolithiasis were longer than that of horizontal semicircular canal-canalithiasis and the age was older.Conclusions The posterior semicircular canal is more involved in BPPV.The latency of vertigo attack of posterior semicircular canal-BPPV is longer than that of horizontal semicircular canal-BPPV.The latency and the duration of vertigo attack of horizontal semicircular canal-cupulolithiasis are longer than that of horizontal semicircular canal-canalithiasis and the age is older.
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Objective:For improving the imperfection of the Active contour model.Methods:This paper puts forward a new active contour model based on the greedy algorithm.The average contour length term is added into the internal energy of the model.The gradient directional energy is introduced to the external energy of the model.A fast algorithm is introduced to solve the minimum of region energy.The algorithm of add or delete snaxel also adopted in this paper.Segmentation of the MRI brain tumor are studied in the experiments.Results:Comparing to the manual segmentation and the GVF segmentation,the method is better.Conclusion:The results of experiments indicate that the model is none sensitive to initial contour.So this algorithm is practical.
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Medical electronics has become an elective or the compulsory course in medical colleges,but the teaching condition has restricted the quality of teaching,so the educational reform is imperative.This article analyzed the medical electronics teaching actuality,and then according to their own teaching reform practice,put forward the future direction of the teaching reform on medical electronics —— strengthening teachers training and improving teaching condition.