Objective To design an experimental device for simulating the interface micro motion of bone trabecular prosthesis and carry out the finite element analysis.Methods The experimental device was composed of a screw-in cylinder with threads,a flexible hinge,a micro-motion rod,a trabecular prosthesis,a connecting rod and a fixation post.A model of the experimental device was constructed with SolidWorks software,and then imported into ABAQUS software to establish a finite element model.An axial displacement load was applied to the femur to analyze the effects of the position of the flexible hinge,the gap between the prosthesis and the femur and the length of the connecting rod on the micro motion.Results The interface micro motion produced by the experimental device increased with the distance of the flexible hinge from the lower end of the screwed-in cylinder;the gap between the prosthesis and the femur did not affect the interface micro motion when the gap was not lower than 20 μm;the interface micro motion rose with the length of the connecting rod.Conclusion The experimental device can accurately simulate the micro motion of different bone trabecular prosthesis interfaces,and can be used for studying the effect of the interface micro motion on osseointegration.[Chinese Medical Equipment Journal,2024,45(1):25-30]

Objective To establish a rapid and convenient UPLC-MS/MS method for the determination of tamoxifen and its active metabolite endoxifen in plasma of patients with breast cancer.Methods With diazepam as the internal standard,the plasma sample was precipitated with acetonitrile and methanol-acetonitrile was used as mobile phase.The samples were separated by chromatographic column ZORBAX Eclipse plus C18(18 μm,2.1 mm x50 mm)and scanned by electrospray ion source and positive ion multiple reaction monitoring mode.The ion channels were detected as tamoxifen m/z 372.0→72.1,endoxifen m/z 374.0→58.2 and diazepam m/z 285→192.9.Results The linearity of tamoxifen and endoxifen were good in the concentration range of 1-500 ng·mL-1(R2=0.999 5)and 0.5-250 ng·mL-1,respectively(R2=0.999 9).The intra-day and inter-day precision of low,medium and high quality control concentrations were all less than 10％.Tamoxifen and endoxifen were stable at low temperature and stable after repeated freeze-thaw.Conclusion The experimental results show that the method meets the requirements of biological sample analysis,and the sample treatment is simple,specific,and can be used for the accurate and rapid determination of tamoxifen and indoloxifen in human plasma.

Objective To investigate the distribution characteristics of pathogens in adult community-acquired pneumonia(CAP)patients who visited the fever clinic before and after the outbreak of the novel coronavirus infection,and to provide theoretical basis for the diagnosis,treatment,and prevention of CAP.Methods CAP patients who visited the fever clinic of Peking University Third Hospital from June 2017 to July 2022 were included in the study and divided into pre-outbreak and post-outbreak groups based on the time point(January 24,2020,when Beijing entered the first-level COVID-19 prevention and control).Respiratory samples were collected and pathogen nucleic acid detection was performed using real-time fluorescence quantitative polymerase chain reaction.The detection and distribution of pathogens were analyzed.Results A total of 415 CAP patients were included,divided into pre-outbreak group(312 cases)and post-outbreak group(103 cases).Mycoplasma pneumoniae,Streptococcus pneumoniae,and Influenza A virus were the three most common pathogens in the pre-outbreak CAP group.In the post-outbreak community-acquired pneumonia,Influenza B virus,Klebsiella pneumoniae and Streptococcus pneumoniae were the three most common pathogens.The incidence of Influenza A virus,Parainflluenza virus,and Mycoplasma pneumoniae was significantly higher in the pre-outbreak period than in the post-outbreak period,and the differences between the two groups were statistically significant(all P＜0.05).Conclusion Before and after the epidemic,viral infection are the main pathogens of CAP patients,which is of great significance for future empirical treatment,protection of susceptible population and control of infectious diseases.

italic>Lamiophlomis rotata is an important medicinal plant species endemic to the Tibetan Plateau, which is prone to strong climate change impacts on its habitable range due to the high sensitivity of the Tibetan Plateau to climate change. Accurate quantification of species vulnerability to climate change is essential for assessing species extinction risk and developing effective conservation strategies. Therefore, we carried out the α-shape analysis to determine the habitat of L. rotata. We then carried out the climate-niche factor analysis (CNFA) to assess the vulnerability of L. rotata to climate change based on five climate variables (i.e., mean diurnal range, temperature seasonality, mean temperature of warmest quarter, precipitation of driest month and precipitation of warmest quarter) in the context of two shared socioeconomic pathways (i.e., SSP126 and SSP585) and three global climate models (CMCC-ESM2: Centro Euro-Mediterraneo sui Cambiamenti Climatici-Earth System Model version 2; HadGEM3-GC31-LL: Hadley Global Environment Model version 3-Global Coupled configuration 3.1; IPSL-CM6A-LR: Institut Pierre Simon Laplace-Climate Model version 6) during two different periods (2041-2060 and 2081-2100). The vulnerability of L. rotata to climate change was calculated by integrating the sensitivity and exposure indices of L. rotata to five climate variables. The results showed that L. rotata had the highest vulnerability to the precipitation of warmest quarter. Its vulnerability within its habitat range generally showed a spatial pattern of high value in the southern region and low in the northern region, high in the western region and low in the eastern region. In general, the vulnerability of L. rotata under the SSP585 scenario was higher than that under the SSP126 scenario. The climate data of different global climate models have some influence on the results, while the resulted uncertainty can be reduced by data integration methods. As a result of climate change, the pressure on the survival of L. rotata in the future will be intensified in the low-altitude areas such as the Yarlung Zangbo River, Yigongzangbu River, Zayu River, and Jiaomuzu River, etc., while the highly weathered scree flats or stony alpine meadows in the high-altitude zones, such as the eastern Tanggula Mountain Range, the northern part of Hengduan Mountain Range, and the western part of the Qinling Mountains, may become its refuge. It is necessary to focus on and strengthen the protection and management of L. rotata resources in these vulnerble and critical areas.

Damarane-type triterpene saponins are the main active ingredients in Gynostemma pentaphyllum (Thunb.) Makino. By using D101 macroporous adsorption resin and silica gel open-columns, C18 medium-pressure column chromatography, and preparative high performance liquid chromatography, we isolated four compounds from the leaves of G. pentaphyllum planted in Guangxi Zhuang Autonomous Region. Their structures were determined by comprehensive analyses of MS, NMR data and circular dichroism spectroscopy and identified as (3β,12β)-dihydroxy-25-peroxyhydrohydrodammarane-20,23-diene-3-O-[β-D-glucopyranosyl(1→2)]-β-D-glucopyranoside (1), (3β,12β,24S)-trihydroxydammarane-20,25-diene-3-O-[β-D-glucopyranosyl(1→2)]-β-D-glucopyranoside (2), (3β,20α)-dihydroxy-24-en-12β,22S-epoxydammarane-3-O-[β-D-glucopyranosyl(1→2)]-β-D-glucopyranoside (3), (3β,12β,20S)-trihydroxydammarane-24-en-3-O-[6-O-acetyl-β-D-glucopyranosyl(1→2)-β-D-glucopyranosyl]-20-O-β-D-xylopyranosyl(1→3)-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside (4). Compounds 1-4 are new dammarane-type triterpene saponins.

This study was aimed at comparing performance differences among three metagenomic sequencing platforms,MGISEQ-2000,Illumina NextSeq 2000,and Ion GeneStudio S5 Plus,to optimize the sequencing process for trace samples.The three sequencing platforms were used to perform high-throughput sequencing on DNA standards and simulated samples.Through analysis of the quality of raw data and microbial detection capabilities,systematic differences among platforms were compared.The sequencing results were optimized for trace samples by incorporation of exogenous nucleic acids during the li-brary preparation process.In terms of data output per batch and base quality,MGISEQ-2000 surpassed the other two plat-forms.Illumina NextSeq 2000 had the lowest proportion of duplicate reads,whereas Ion GeneStudio S5 Plus had the highest proportion,and significant differences were observed across platforms(P＜0.001).In sequencing uniformity,MGISEQ-2000 and Illumina NextSeq 2000 were superior to Ion GeneStudio S5 Plus.MGISEQ-2000 provided a substantial advantage in microbial detection capability(P＜0.001),but the advantage diminished with decreasing bacterial fluid concentration.Ion GeneStudio S5 Plus had the shortest duration for single-batch sequencing.Moreo-ver,for trace samples with DNA content ≤0.05 ng,the experi-mental group(with added exogenous nucleic acids)achieved a higher number of reads than the control group(without exogenous nucleic acids),with a 11.09±8.03 fold increase.In conclu-sion,the different sequencing platforms each had advantages and disadvantages,thus allowing researchers to choose the appro-priate platform according to specific needs.Furthermore,the addition of exogenous nucleic acids improved the microorganism detection efficiency,and provided better support for subsequent diagnosis and evaluation of results.

Objective:To retrospectively analyze the detection and diagnosis process of two cases with double rare thalassemia genotypes,explore the causes of missed diagnosis and misdiagnosis of rare thalassemia,and improve the diagnosis level of rare thalassemia.Methods:Base on the family history,hematological phenotype and hemoglobin electrophoretic analysis results,the common genotypes of α and β-thalassemia were detected by PCR+diversion hybridization.DNA sequencing technology was used for rare α and β protein genes sequencing.Results:Both subjects were combined with double rare thalassemia genotypes,and both rare thalassemia gene combinations were reported for the first time.One of them was αβ complex thalassemia with αα*53_55 del TCC/αα heterozygous merger βIVS Ⅱ2(-T)/βN heterozygous,the other was ααIVS-Ⅱ-55(T→G)in α1/αα4,2-Q double azygous heterozygous α-thalassemia,among whichαα*53_55 del TCC/αα genotype was also reported for the first time.Conclusion:The reported rare gene type αα*53_55 del TCC/αα and two cases of rare gene combinations enriches the spectrum of gene mutations in the Chinese population,and provides richer molecular information for thalassemia diagnosis and eugenics counseling.

Aim To study the effect of Guben Yanling pills on liver aging in aging mice and the related mech-anism.Methods The mice were randomly divided in-to blank control group,model group,vitamin E group(0.1 g·kg-1)and low,medium and high dose groups(0.59,1.17,2.34 g·kg-1)of Guben Yan-ling pills.The aging mouse model was established by subcutaneous injection of D-galactose(150 mg·kg-1)into the back of neck.At the same time of mod-eling,the corresponding drugs were given by gavage once a day for six weeks.The main organ indexes were calculated.HE staining was used to observe the mor-phology of liver tissue.Colorimetry was used to detect the activity of β-galactosidase in liver.ELISA was used to detect the content of TNF-α,IL-1 β,IL-6,IL-4,IL-10.Western blot was used to detect the protein relative expression level of IKKβ,Iκ Bα,NF-κB p65.Immunofluorescence was used to detect the expression level of NF-κB p65.Results Compared with the blank control group,the organ index of the brain,liv-er,kidney,spleen,and thymus in the model group decreased(P＜0.05,P＜0.01),the activity of β-galactosidase increased(P＜0.01),liver tissue mor-phology and structure were significantly damaged,the content of TNF-α,IL-1 β and IL-6 increased(P＜0.01),the content of IL-4 and IL-10 decreased(P＜0.01),the levels of IKKβ,NF-κB p65 in-creased(P＜0.01),the levels of IKBα decreased(P＜0.01),and the levels of NF-κB p65 in nucleus increased(P＜0.01).Compared with the model group,the organ indexes of brain,liver,kidney,spleen,and thymus in each dose group of Guben Yan-ling pills increased(P＜0.05,P＜0.01),the activity of β-galactosidase decreased(P＜0.01),the morpho-logical and structural damage of liver tissue was signifi-cantly improved,the content of TNF-α,IL-1 β and IL-6 decreased(P＜0.01),the content of IL-4 and IL-10 increased(P＜0.01),the levels of IKKβ,NF-κB p65 decreased(P＜0.01),the levels of IκBα in-creased(P＜0.01),and the levels of NF-κB p65 in nucleus decreased(P＜0.01).Conclusions Guben Yanling pills can antagonize liver aging in mice,and its mechanism may be related to inhibiting the activa-tion of NF-κB signaling pathway in liver,downregulat-ing downstream pro-inflammatory factor levels,upregu-lating anti-inflammatory factor levels,and alleviating inflammation in liver.

Objective: This meta-analysis aims to refine the understanding of the optimal choice between different cage shapes in transforaminal lumbar interbody fusion (TLIF) by systematically comparing perioperative data, radiological outcomes, clinical results, and complications associated with banana-shaped and straight bullet cages. Methods: A meticulous literature search encompassing PubMed, Embase, Scopus, Web of Science, China Knowledge Network, and Wanfang Data was executed up to October 5, 2023. Inclusion criteria focused on studies comparing banana-shaped and straight bullet cages in TLIF. The quality of included studies was assessed using appropriate tools such as the Newcastle-Ottawa Scale (NOS) for nonrandomized studies. Rigorous evaluations were performed for radiographic outcomes, including disc height (DH), segmental lordosis (SL), lumbar lordosis (LL), subsidence, and fusion rates. Clinical outcomes were meticulously evaluated using visual analogue scale (VAS), Oswestry Disability Index (ODI), and complications. Results: The analysis incorporated 7 studies, involving 573 patients (297 with banana-shaped cages, 276 with straight cages), all with NOS ratings exceeding 5 stars. No statistically significant differences were observed in operative time, blood loss, or hospitalization between the 2 cage shapes. Banana-shaped cages exhibited greater changes in DH (p = 0.001), SL (p = 0.02), and LL (p = 0.01). Despite statistically higher changes in ODI for straight cages (26.33, p < 0.0001), the actual value remained similar to banana-shaped cages (26.15). Both cage types demonstrated similar efficacy in VAS, complication rates, subsidence, and fusion rates. Conclusion Although banana-shaped cages can excel in restoring DH, SL, and LL, straight bullet cages can provide comparable functional improvements, pain relief, and complication rates.

Objective: This meta-analysis aims to refine the understanding of the optimal choice between different cage shapes in transforaminal lumbar interbody fusion (TLIF) by systematically comparing perioperative data, radiological outcomes, clinical results, and complications associated with banana-shaped and straight bullet cages. Methods: A meticulous literature search encompassing PubMed, Embase, Scopus, Web of Science, China Knowledge Network, and Wanfang Data was executed up to October 5, 2023. Inclusion criteria focused on studies comparing banana-shaped and straight bullet cages in TLIF. The quality of included studies was assessed using appropriate tools such as the Newcastle-Ottawa Scale (NOS) for nonrandomized studies. Rigorous evaluations were performed for radiographic outcomes, including disc height (DH), segmental lordosis (SL), lumbar lordosis (LL), subsidence, and fusion rates. Clinical outcomes were meticulously evaluated using visual analogue scale (VAS), Oswestry Disability Index (ODI), and complications. Results: The analysis incorporated 7 studies, involving 573 patients (297 with banana-shaped cages, 276 with straight cages), all with NOS ratings exceeding 5 stars. No statistically significant differences were observed in operative time, blood loss, or hospitalization between the 2 cage shapes. Banana-shaped cages exhibited greater changes in DH (p = 0.001), SL (p = 0.02), and LL (p = 0.01). Despite statistically higher changes in ODI for straight cages (26.33, p < 0.0001), the actual value remained similar to banana-shaped cages (26.15). Both cage types demonstrated similar efficacy in VAS, complication rates, subsidence, and fusion rates. Conclusion Although banana-shaped cages can excel in restoring DH, SL, and LL, straight bullet cages can provide comparable functional improvements, pain relief, and complication rates.