AIM To study the chemical constituents from the leaves of Drynaria fortunei(Kunze)J.Sm.and their antioxidant activity.METHODS ODS-AG-HG,Sephadex LH-20 and semi-preparative HPLC were used for separation and purification,then the structures of obtained compounds were identified by physicochemical properties and spectral data.The antioxidant activity was determined by DPPH mothod.RESULTS Fifteen compounds were isolated and identified as kaempferol-3-O-neohesperidoside(1),dihydrodehydrodiconiferyl alcohol(2),kaempferol-3,7-di-O-α-L-rahmnoside(3),astragalin(4),loliolid(5),trichothecene analogue(6),2,2-[bis-4-(2,3-dihydroxypropoxy)phenyl]propane(7),maculatin(8),trichothecin(9),4-[(Z)-but-2-enoyloxy]-8-chloro-12-hydroxy-7,13-epoxytrichothec-9-ene(10),8-deoxy-trichotecin(11),β-sitosterol(12),daucosterol(13),afzelin(14),samwinol(15).The IC50 values of the leaf and rhizome extracts against DPPH free radicals were(0.072±0.005),(0.287±0.012)mg/mL,respectively.CONCLUSION Compounds 1,2,5-11,15 are isolated from this plant for the first time.The leaves of D.fortunei exhibit strong antioxidant activity.

The existing relevant standards and registration of disposable sterile surgical drapes were introduced,and four times of national supervision and sample inspection of disposable sterile surgical drapes from 2017 to 2023 were described.The unqualified items found in the supervision and sample inspection were analyzed,the exploratory research projects carried out were summarized and other problems encountered during the sample inspection were pointed out.Relevant enterprises were suggested to strengthen the implementation of industry standards,take seriously the product material identification information,clearly limit the raw materials used and standardize the product registration name.References were provided for the industrial supervision and development of disposable sterile surgical drapes.[Chinese Medical Equipment Journal,2025,46(5):66-72]

The existing relevant standards and registration of disposable sterile surgical drapes were introduced,and four times of national supervision and sample inspection of disposable sterile surgical drapes from 2017 to 2023 were described.The unqualified items found in the supervision and sample inspection were analyzed,the exploratory research projects carried out were summarized and other problems encountered during the sample inspection were pointed out.Relevant enterprises were suggested to strengthen the implementation of industry standards,take seriously the product material identification information,clearly limit the raw materials used and standardize the product registration name.References were provided for the industrial supervision and development of disposable sterile surgical drapes.[Chinese Medical Equipment Journal,2025,46(5):66-72]

AIM To study the chemical constituents from the leaves of Drynaria fortunei(Kunze)J.Sm.and their antioxidant activity.METHODS ODS-AG-HG,Sephadex LH-20 and semi-preparative HPLC were used for separation and purification,then the structures of obtained compounds were identified by physicochemical properties and spectral data.The antioxidant activity was determined by DPPH mothod.RESULTS Fifteen compounds were isolated and identified as kaempferol-3-O-neohesperidoside(1),dihydrodehydrodiconiferyl alcohol(2),kaempferol-3,7-di-O-α-L-rahmnoside(3),astragalin(4),loliolid(5),trichothecene analogue(6),2,2-[bis-4-(2,3-dihydroxypropoxy)phenyl]propane(7),maculatin(8),trichothecin(9),4-[(Z)-but-2-enoyloxy]-8-chloro-12-hydroxy-7,13-epoxytrichothec-9-ene(10),8-deoxy-trichotecin(11),β-sitosterol(12),daucosterol(13),afzelin(14),samwinol(15).The IC50 values of the leaf and rhizome extracts against DPPH free radicals were(0.072±0.005),(0.287±0.012)mg/mL,respectively.CONCLUSION Compounds 1,2,5-11,15 are isolated from this plant for the first time.The leaves of D.fortunei exhibit strong antioxidant activity.

Objective:To assess the deformation of the bladder-neck opening and the impact of the bladder-neck angle(BNA)on urination in male patients by fluid-structure interaction(FSI)analysis.Methods:We established geometric models of the blad-der,prostate and urethra were established,incorporating both normal and enlarged BNAs,and assessed the effects of BNA alteration on urinary flow by FSI simulation of the flow rate and pressure of the urine within the bladder,bladder neck and urethra,and that of pros-tate displacement as well.We retrospectively analyzed the clinical data on 145 male patients from the Second Hospital of Hebei Medical University between June 2020 and June 2023,39 with acute urine retention(the AUR group)and 106 without(the non-AUR group),and evaluate the impact of BNA on urination based on the urinary flow rate and prostate volume.Results:Comparative simulation a-nalysis showed significant differences in the total urethral pressure and flow rate between the normal and enlarged BNA models(P＜0.05).The maximum prostate displacement was found at the bladder neck,with moderate displacement and unchanged urethral diame-ter in the normal BNA model,but significant displacement and a reduced urethral opening diameter in the enlarged BNA model.FSI analysis confirmed an evident impact of enlarged BNA on urination,more significant in the AUR than in the non-AUR patients(P＜0.05).The BNAs in the patients with the maximum urinary flow rate(Qmax)of＜10,10-15 or＞15 ml/s were 83.7°±2.5°,67.5°±1.8° and 65.1°±4.8° respectively,with statistically significant difference between the former one and the latter two groups(P＜0.05).The BNAs in the patients with normal prostate volume or BPH of grade Ⅰ,Ⅱ,Ⅲ or Ⅳ were 65.0°±3.7°,67.2°±3.1°,71.5°±2.0°,82.8°±3.5° and 105.8°±6.0°,respectively(P＜0.05),with statistically significant difference between BPH grades Ⅲ and Ⅳ(P＜0.05)as well as between these two and the other three groups(P＜0.05),but not among the normal prostate volume,BPH grade Ⅰ and BPH grade Ⅱ groups(P＞0.05).Spearman correlation analysis indicated that BNA was strongly correlated with total prostate volume(TPV),transition zone volume(TZV),intravesical prostatic protrusion(IPP),prostatic urethral angle(PUA),IPSS,and Qmax(P＜0.05).Conclusion:Changes in BNA affect urination and are closely associated with the se-verity of prostate hyperplasia.The BNA may be an important anatomical factor for assessing the severity of lower urinary tract symptoms in BPH patients.

Objective To propose a Q factor-based fatigue vibration evaluation method of the ultrasonic knife tip.Methods Firstly,an ultrasonic cutter fatigue testing table was established to realize repeated cutting,which was composed of a power supply module,a three-axis moving module,an ultrasonic cutter clamping module and a control module.Secondly,10 ultrasonic knives of some brand underwent fatigue testing with the table,during which non-contact measurement of the ultrasonic knife tip vibration was carried out and the Q factors were calculated at the five periods of the fatigue test,including the periods before cutting,after 500 times of cutting,after 1 000 times of cutting,after 2 000 times of cutting and after 3 000 times of cutting.Finally,the average cutting speed and burst pressure for coagulated vessels were computed at each period to validata the effectiveness of the method proposed.Results It's indicated that Q factor could effectively reflect the fatigue degradation of the ultrasonic knife tip,while the average cutting speed and burst pressure for coagulated vessels were difficult to efficiently evaluate the fatigue degradation level of the ultrasonic knife tip due to the uncertainty factors in the measurement process.Conclusion The proposed Q factor-based evaluation method can directly evaluate fatigue vibration of the ultrasonic knife tip in an accurate and quantitative manner.[Chinese Medical Equipment Journal,2024,45(6):17-22]

Objective To carry out accurate quantative evaluation of MRI scanning noise based on laser vibrometry technology.Methods Skull and spine MRI was performed with mute and conventional sequences.A laser vibrometry device was used to sample the surface vibration noise at the outer edge of the inspection hole of MRI system according to GB/T 16539-1996 Acoustics—Determination of sound power levels of noise sources using vibration velocity—Measurement for seal machinery,and the indicators of sound power level,sound pressure level and perceived noise level obtained by the three calculation methods(LPN1,LPN2 and LPN3)were analyzed with some dedicated MRI noise analysis software.Results The peak sound pressure levels for conventional and mute sequences of skull scanning were 81 and 63 dB(A),respectively,and mute sequence reduced the noise level significantly;the peak sound pressure levels for conventional and mute sequences of spine scanning were 79 and 75 dB(A),respectively,and the noise reduction level was significantly lower than that of skull scanning.Significant differences in noise reduction were not found in spine scanning sequences,while were found in skull scanning sequences.During spine and skull scanning LPN1,LPN2 and LPN3 obtained by the three calculation methods of conventional and mute sequences were all higher than the overall sound power and overall pressure levels obviously.Conclusion Mute sequence can not realize linear noise reduction for the whole frequency band,the perceived noise of the human ear during MRI scanning is related directly to the scanning sequence,and there may be some bias when only one physical indicator is involved in the noise evaluation of MRI system.[Chinese Medical Equipment Journal,2024,45(10):20-24]

The assessment of adverse drug events is an important basis for clinical safety evaluation and post-marketing risk control of drugs,and its causality assessment is gaining increasing attention.The existing methods for assessing the causal relationship between drugs and the occurrence of adverse reactions can be broadly classified into three categories:global introspective methods,standardized methods,and probabilistic methods.At present,there is no systematic introduction of the operational details of the various methods in the domestic literature.This paper compares representative causality assessment methods in terms of definition and concept,methodological steps,industry evaluation and advantages and disadvantages,clarifies the basic process of determining the causality of adverse drug reactions,and discusses how to further improve the adverse drug reaction monitoring and evaluation system,with a view to providing a reference for drug development and pharmacovigilance work in China.

Bacterial biofilms gave rise to persistent infections and multi-organ failure, thereby posing a serious threat to human health. Biofilms were formed by cross-linking of hydrophobic extracellular polymeric substances (EPS), such as proteins, polysaccharides, and eDNA, which were synthesized by bacteria themselves after adhesion and colonization on biological surfaces. They had the characteristics of dense structure, high adhesiveness and low drug permeability, and had been found in many human organs or tissues, such as the brain, heart, liver, spleen, lungs, kidneys, gastrointestinal tract, and skeleton. By releasing pro-inflammatory bacterial metabolites including endotoxins, exotoxins and interleukin, biofilms stimulated the body’s immune system to secrete inflammatory factors. These factors triggered local inflammation and chronic infections. Those were the key reason for the failure of traditional clinical drug therapy for infectious diseases.In order to cope with the increasingly severe drug-resistant infections, it was urgent to develop new therapeutic strategies for bacterial-biofilm eradication and anti-bacterial infections. Based on the nanoscale structure and biocompatible activity, nanobiomaterials had the advantages of specific targeting, intelligent delivery, high drug loading and low toxicity, which could realize efficient intervention and precise treatment of drug-resistant bacterial biofilms. This paper highlighted multiple strategies of biofilms eradication based on nanobiomaterials. For example, nanobiomaterials combined with EPS degrading enzymes could be used for targeted hydrolysis of bacterial biofilms, and effectively increased the drug enrichment within biofilms. By loading quorum sensing inhibitors, nanotechnology was also an effective strategy for eradicating bacterial biofilms and recovering the infectious symptoms. Nanobiomaterials could intervene the bacterial metabolism and break the bacterial survival homeostasis by blocking the uptake of nutrients. Moreover, energy-driven micro-nano robotics had shown excellent performance in active delivery and biofilm eradication. Micro-nano robots could penetrate physiological barriers by exogenous or endogenous driving modes such as by biological or chemical methods, ultrasound, and magnetic field, and deliver drugs to the infection sites accurately. Achieving this using conventional drugs was difficult. Overall, the paper described the biological properties and drug-resistant molecular mechanisms of bacterial biofilms, and highlighted therapeutic strategies from different perspectives by nanobiomaterials, such as dispersing bacterial mature biofilms, blocking quorum sensing, inhibiting bacterial metabolism, and energy driving penetration. In addition, we presented the key challenges still faced by nanobiomaterials in combating bacterial biofilm infections. Firstly, the dense structure of EPS caused biofilms spatial heterogeneity and metabolic heterogeneity, which created exacting requirements for the design, construction and preparation process of nanobiomaterials. Secondly, biofilm disruption carried the risk of spread and infection the pathogenic bacteria, which might lead to other infections. Finally, we emphasized the role of nanobiomaterials in the development trends and translational prospects in biofilm treatment.

ObjectiveThe scale of microalgae farming industry is huge. During farming, it is easy for microalgae to be affected by miscellaneous bacteria and other contaminants. Because of that, periodic test is necessary to ensure the growth of microalgae. Present microscopy imaging and spectral analysis methods have higher requirements for experiment personnel, equipment and sites, for which it is unable to achieve real-time portable detection. For the purpose of real-time portable microalgae detection, a real-time microalgae detection system of low detection requirement and fast detection speed is needed. MethodsThis study has developed a microalgae detection system based on deep learning. A microscopy imaging device based on bright field was constructed. With imaged captured from the device, a neural network based on YOLOv3 was trained and deployed on microcomputer, thus realizing real-time portable microalgae detection. This study has also improved the feature extraction network by introducing cross-region residual connection and attention mechanism and replacing optimizer with Adam optimizer using multistage and multimethod strategy. ResultsWith cross-region residual connection, the mAP value reached 0.92. Compared with manual result, the detection error was 2.47%. ConclusionThe system could achieve real-time portable microalgae detection and provide relatively accurate detection result, so it can be applied to periodic test in microalgae farming.