Objectives:To analyze the mechanical properties of the personalized artificial vertebral body of 3D-printed poly etheretherketone(PEEK)matrix composites after implantation and its effect on adjacent tissues using finite element analysis.Methods:The CT scan data of a healthy male volunteer was extracted for 3D reconstruction,the finite element model of the lumbar spine(L1-L5)was constructed,and the ranges of motion of different lumbar vertebrae segments in various motion states were simulated,after that,the effectiveness of the finite element model was verified by comparing with the research data in previous studies.The total en bloc spondylectomy(TES)was simulated to remove the L3 vertebral body and adjacent intervertebral discs,and a personalized artificial vertebral body was designed based on the design principles of artificial vertebral body and was fixed to the adjacent lumbar segments using a posterior approach with a titanium alloy rod-screw system.The interior of the artificial vertebral body was designed as honeycomb structures with densities of 30％,50％,and 70％.PEEK/hydroxylaptite(HA)composite materials were selected as the external shell of the personalized lumbar artificial vertebral body,and PEEK/carbon fiber(CF)materials were used as the internal filler.The forces and moments of each vertebral body in the upright,forward bending,backward extension,lateral bending and rotation states were obtained through the Vicon Nexus system,and as the boundary con-ditions of finite element analysis,the appropriate size of the bone graft hole and the thickness of the shell were selected,and then the inside of the artificial vertebral body was filled with hexagonal honeycombs of different densities.The models of young and middle-aged and elderly groups were established by changing the elastic modulus of cortical bone and cancellous bone,and the finite element simulation was carried out on the models.The maximum stress values of the artificial vertebral body,fixation system and adjacent upper and lower endplates under different motion states,and the stress occlusion rate of the artificial vertebral body were analyzed to evaluate the performance of the artificial vertebral body.Results:The maximum stress value of artificial vertebral body(42.25MPa)was lower than the yield strength of PEEK/HA(65MPa),and the maximum stress value of internal honeycomb(26.38MPa)was lower than the yield strength of PEEK/CF(90MPa);The maximum stress value of rod-screw system(271.75MPa)was lower than the yield strength of titanium alloy(900MPa),and the maximum stress value of the endplate on adjacent endplate(7.87MPa)was lower than the yield strength of cartilage endplate(50MPa).The stress occlusion rate of artificial vertebral body with 30％honeycomb density in the middle-aged and elderly group was the lowest.Conclusions:The 3D-printed personalized artificial vertebral body of PEEK matrix composite can complete the structure reconstruction of lumbar spine well after TES with good biomechanical stability.

Objective:To investigate the effect of internet-based perinatal nutrition clinic initiated management at different trimesters on pregnancy outcomes.Methods:Adopting a retrospective study design,1120 singleton pregnant women registered at Nanning Maternal and Child Health Hospital from March 2021 to March 2022 were included.Randomly divided into early pregnancy intervention group(single day randomized,n=551)and mid pregnancy intervention group(double day randomized,n=569)based on the registation date.Both groups received internet-based perinatal nutrition clinic initiated management.The general information,pre pregnancy BMI,weight gain during pregnancy and pregnancy outcomes between two groups were compared.The pregnancy outcomes of two different pre pregnancy weight classification groups were compared.Results:Compared of age and weight gain during pregnancy between early pregnancy intervention group and mid pregnancy intervention group,the difference was statistically significant(P＜0.05).Compared of delivery mode,hypertensive disorders of pregnancy(HDP),gestational diabetes mellitus(GDM)and macrosomia between the early pregnancy intervention group and the mid pregnancy intervention group,the difference was statistically significant(P＜0.05).Compared of low birth weight infants and weight gain during pregnancy in low body weight group between early intervention and mid intervention,the difference was statistically significant(P＜0.05).Compared of delivery mode,GDM and weight gain during pregnancy in normal weight group between early intervention and mid intervention,the difference was statistically significant(P＜0.05).Compared of delivery mode,HDP,GDM,postpartum hemorrhage,macrosomia and weight gain during pregnancy in overweight group between early intervention and mid intervention,the difference was statistically significant(P＜0.05).Compared of delivery mode,HDP,GDM and weight gain during pregnancy in obesity group between early intervention and mid intervention,the difference was statistically significant(P＜0.05).Conclusion:Early pregnancy nutrition weight management based on internet-based perinatal nutrition clinic can regulate the rate of weight gain during pregnancy,can effectively reduce the risk of HDP,GDM and cesarean section.

Objective:To investigate the effect of internet-based perinatal nutrition clinic initiated management at different trimesters on pregnancy outcomes.Methods:Adopting a retrospective study design,1120 singleton pregnant women registered at Nanning Maternal and Child Health Hospital from March 2021 to March 2022 were included.Randomly divided into early pregnancy intervention group(single day randomized,n=551)and mid pregnancy intervention group(double day randomized,n=569)based on the registation date.Both groups received internet-based perinatal nutrition clinic initiated management.The general information,pre pregnancy BMI,weight gain during pregnancy and pregnancy outcomes between two groups were compared.The pregnancy outcomes of two different pre pregnancy weight classification groups were compared.Results:Compared of age and weight gain during pregnancy between early pregnancy intervention group and mid pregnancy intervention group,the difference was statistically significant(P＜0.05).Compared of delivery mode,hypertensive disorders of pregnancy(HDP),gestational diabetes mellitus(GDM)and macrosomia between the early pregnancy intervention group and the mid pregnancy intervention group,the difference was statistically significant(P＜0.05).Compared of low birth weight infants and weight gain during pregnancy in low body weight group between early intervention and mid intervention,the difference was statistically significant(P＜0.05).Compared of delivery mode,GDM and weight gain during pregnancy in normal weight group between early intervention and mid intervention,the difference was statistically significant(P＜0.05).Compared of delivery mode,HDP,GDM,postpartum hemorrhage,macrosomia and weight gain during pregnancy in overweight group between early intervention and mid intervention,the difference was statistically significant(P＜0.05).Compared of delivery mode,HDP,GDM and weight gain during pregnancy in obesity group between early intervention and mid intervention,the difference was statistically significant(P＜0.05).Conclusion:Early pregnancy nutrition weight management based on internet-based perinatal nutrition clinic can regulate the rate of weight gain during pregnancy,can effectively reduce the risk of HDP,GDM and cesarean section.

Objective This study analyzed the chemical structures of two unknown substances in e-liquid using methods such as nuclear magnetic resonance(NMR),infrared spectroscopy(IR),and mass spectrometry(MS).Methods After separating,purifying,and freeze-drying two suspicious substances from e-liquid,GC-MS analysis was used to obtain the mass spectrum characteristic ion fragments and fragmentation patterns of unknown compounds.The precise mass numbers were measured by high-resolution mass spectrometry,and proton numbers and their assignments,carbon types,and fluorine atom numbers and positions were obtained by combining 1HNMR,13CNMR,and 19FNMR.The functional groups were then analyzed by infrared spectroscopy.Results Through data analysis,the molecular formulas of the two suspicious substances are C13H13FN2O2 and C14H15FN2O2,respectively.Their structures were determined to be etomidate derivatives:1-(o-fluoromethylphenyl)imidazole-5-carboxylic acid methyl ester and 1-(o-fluoromethylphenyl)imidazole-5-carboxylic acid ethyl ester.Conclusion The structural data of two substances obtained in this study in terms of mass spectrometry,nuclear magnetic resonance,and infrared spectroscopy provide support for combating crimes involving the two substances,and provide reference for the regulation and detection of the two drugs.

BACKGROUND:Black phosphorus has a high degree of homology with human bone,so it has been extensively studied in the field of bone tissue engineering in recent years.Since 2014,two-dimensional black phosphorus materials have garned significant attention in the field of biomedicine due to their excellent exceptional physical,chemical,and biological properties. OBJECTIVE:To summarize the advancements made in black phosphorus-based nanomaterials for bone tissue engineering,focus on the synthesis methods,osteogenic characteristics,and applications in biomaterials pertaining to two-dimensional black phosphorus nanomaterials. METHODS:Chinese and English key words were"black phosphorus,bone tissue engineering,bone defect,bone regeneration,osteogenesis."Relevant articles in PubMed and CNKI databases from January 2014 to December 2023 were searched.After exclusion and screening,96 articles were analyzed. RESULTS AND CONCLUSION:Black phosphorus nanomaterials play an important role in bone tissue engineering due to their good biocompatibility,biodegradability,photothermal action,antibacterial ability,drug loading performance,and special osteogenic effect,and are ideal candidate materials for promoting bone regeneration.The preparation of black phosphorus nanomaterials is mainly a top-down top-layer stripping method.The main principle is to weaken the van der Waals force between the black phosphorus layers by physical or chemical means to obtain a single or less layer of phosphanse,that is,black phosphorus nanosheets or quantum dots.Black phosphate-based nanocomposites are mainly divided into hydrogels,3D printing scaffolds,composite scaffolds,electrospinning,bionic periosteum,microspheres,and bionic coatings.The research of nano-black phosphorus in bone tissue engineering is in its infancy,and still faces many challenges:the behavior of black phosphorus in vivo and the interaction mechanism with various biomolecules need to be further studied.The long-term potential toxicity of black phosphorus is unknown.The manufacturing process for black phosphorus is difficult to control.Therefore,how to develop uniform size,safe,reliable,and efficient nano black phosphorus and transform it into clinical application requires interdisciplinary research on modern biomedical technology,physicochemical technology,and precision manufacturing technology.

Objective This study analyzed the chemical structures of two unknown substances in e-liquid using methods such as nuclear magnetic resonance(NMR),infrared spectroscopy(IR),and mass spectrometry(MS).Methods After separating,purifying,and freeze-drying two suspicious substances from e-liquid,GC-MS analysis was used to obtain the mass spectrum characteristic ion fragments and fragmentation patterns of unknown compounds.The precise mass numbers were measured by high-resolution mass spectrometry,and proton numbers and their assignments,carbon types,and fluorine atom numbers and positions were obtained by combining 1HNMR,13CNMR,and 19FNMR.The functional groups were then analyzed by infrared spectroscopy.Results Through data analysis,the molecular formulas of the two suspicious substances are C13H13FN2O2 and C14H15FN2O2,respectively.Their structures were determined to be etomidate derivatives:1-(o-fluoromethylphenyl)imidazole-5-carboxylic acid methyl ester and 1-(o-fluoromethylphenyl)imidazole-5-carboxylic acid ethyl ester.Conclusion The structural data of two substances obtained in this study in terms of mass spectrometry,nuclear magnetic resonance,and infrared spectroscopy provide support for combating crimes involving the two substances,and provide reference for the regulation and detection of the two drugs.

Lumbosacral radiculopathy refers to the pain syndrome caused by inflammation or mechanical compression of the lumbar nerve root, mainly manifested as low back pain, and radiating to the lower limbs in cutaneous mode, which can be accompanied by numbness, paresthesia, tingling, muscle weakness and loss of specific reflexes and other symptoms, which not only bring physical pain and life inconvenience to the patients, but also bring huge economic burden to the social medical care. Selective nerve root block(SNRB), as a safe, effective, low-cost, precise and minimally invasive clinical technique, can accurately intervene in specific nerve roots and quickly relieve pain symptoms by reducing inflammation and improving the surrounding environment of nerves. However, there are still many challenges and controversies in practice, such as precise targeting requirements, drug selection, potential risks and complications, and differences in efficacy among different patient populations. The purpose of this review is to systematically review and analyze the existing research results on SNRB, so as to provide useful reference and guidance for the further development of this field.

INTRODUCTION: This review aims to provide evidence-based recommendations for an enhanced primary series (third dose) coronavirus disease 2019 (COVID-19) vaccination in people with rheumatic diseases (PRDs) in the local and regional context. METHODS: Literature reviews were performed regarding the necessity, efficacy, safety and strategies for enhanced primary series COVID-19 vaccination in PRDs. Recommendations were developed based on evidence according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. Evidence was synthesised by eight working group members, and the consensus was achieved by a Delphi method with nine members of an expert task force panel. RESULTS: Two graded recommendations and one ungraded position statement were developed. PRDs have impaired immunogenicity from the COVID-19 vaccine and are at an increased risk of postvaccine breakthrough severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and poor clinical outcomes, compared to the general population. We strongly recommend that PRDs on immunomodulatory drugs be offered a third dose of the messenger RNA (mRNA) vaccine as part of an enhanced primary series, after the standard two-dose regimen. We conditionally recommend that the third dose of mRNA vaccine against SARS-CoV-2 be given at least 4 weeks after the second dose or as soon as possible thereafter. There is insufficient data to inform whether the third mRNA vaccine should be homologous or heterologous in PRDs. CONCLUSION These recommendations that were developed through evidence synthesis and formal consensus process provide guidance for an enhanced primary series COVID-19 vaccination in PRDs.
Humans ; COVID-19/prevention & control* ; COVID-19 Vaccines/administration & dosage* ; Rheumatic Diseases/immunology* ; Singapore ; SARS-CoV-2 ; Vaccination/methods* ; Delphi Technique ; Immunization, Secondary