Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.

OBJECTIVE: To evaluate the efficacy and safety of Shexiang Tongxin Dropping Pill (STDP) in treating stable angina patients with phlegm-heat and blood-stasis syndrome by exercise duration and metabolic equivalents. METHODS: This multicenter, randomized, double-blind, placebo-controlled clinical trial enrolled stable angina patients with phlegm-heat and blood-stasis syndrome from 22 hospitals. They were randomized 1:1 to STDP (35 mg/pill, 6 pills per day) or placebo for 56 days. The primary outcome was the exercise duration and metabolic equivalents (METs) assessed by the standard Bruce exercise treadmill test after 56 days of treatment. The secondary outcomes included the total angina symptom score, Chinese medicine (CM) symptom scores, Seattle Angina Questionnaire (SAQ) scores, changes in ST-T on electrocardiogram and adverse events (AEs). RESULTS: This trial enrolled 309 patients, including 155 and 154 in the STDP and placebo groups, respectively. STDP significantly prolonged exercise duration with an increase of 51.0 s, compared to a decrease of 12.0 s with placebo (change rate: -11.1% vs. 3.2%, P<0.01). The increase in METs was significantly greater in the STDP group than in the placebo group (change: -0.4 vs. 0.0, change rate: -5.0% vs. 0.0%, P<0.01). The improvement of total angina symptom scores (25.0% vs. 0.0%), CM symptom scores (38.7% vs. 11.8%), reduction of nitroglycerin consumption (100.0% vs. 11.3%), and all domains of SAQ, were significantly greater with STDP than placebo (all P<0.01). The changes in Q-T intervals at 28 and 56 days from baseline were similar between the two groups (both P>0.05). Twenty-five participants (16.3%) with STDP and 16 (10.5%) with placebo experienced AEs (P=0.131), with no serious AEs observed. CONCLUSION STDP could improve exercise tolerance in patients with stable angina and phlegm-heat and blood stasis syndrome, with a favorable safety profile. (Registration No. ChiCTR-IPR-15006020).
Humans ; Double-Blind Method ; Drugs, Chinese Herbal/adverse effects* ; Male ; Female ; Middle Aged ; Angina, Stable/physiopathology* ; Aged ; Syndrome ; Treatment Outcome ; Placebos ; Tablets

Aim To investigate the regulatory role and mechanism of resveratrol in inhibiting autophagy and promoting apoptosis in choroidal melanoma cells. Methods Choroidal melanoma cells (MUM2B) were divided into control and experimental groups, and treated with different concentrations of resveratrol (0, 10, 20,40,60,80 μmol ·L

Human brain banks use a standardized protocol to collect,process and store post-mortem human brains and related tissues,along with relevant clinical information,and to provide the tissue samples and data as a resource to foster neuroscience research according to a standardized operating protocols(SOP).Human brain bank serves as the foundation for neuroscience research and the diagnosis of neurological disorders,highlighting the crucial rule of ensuring the consistency of standardized quality for brain tissue samples.The first version of SOP in 2017 was published by the China Human Brain Bank Consortium.As members increases from different regions in China,a revised SOP was drafted by experts from the China Human Brain Bank Consortium to meet the growing demands for neuroscience research.The revised SOP places a strong emphasis on ethical standards,incorporates neuropathological evaluation of brain regions,and provides clarity on spinal cord sampling and pathological assessment.Notable enhancements in this updated version of the SOP include reinforced ethical guidelines,inclusion of matching controls in recruitment,and expansion of brain regions to be sampled for neuropathological evaluation.

Objective To explore the modal testing method for the three-axis manned centrifuge under elastic boundary conditions with considerations on its complicated structure and high rotational inertia.Methods Modal testing was carried out with a three-axis manned centrifuge under elastic boundary conditions as the subject and a force hammer as the excitation source according to GJB 2706A-2008 Modal tests method for spacecraft and GB/T 11349.3-1992 Experimental determination of mechnical mobility measurements using impact excitation.Four times of hammering were carried out at each excitation position,and the data of the four times of hammering underwent linear average computation.Data acquisition was implemented with a three-axis accelerometer and a 64-channel data collector,and the modal data were analyzed using a frequency response function based on the Test.Lab modal test and analysis software.Results The coherence coefficient of the excitation signal was not lower than 0.8 in the 30 Hz band;the first three orders of the system's intrinsic vibrations were all torsional vibrations,with the frequencies of 9.15,15.66 and 19.22 Hz,respectively;the first order frequency of the system was about 9.15 Hz for both Z18 and Z21 excitation positions,and each of the second and third order frequencies similar situations were observed for also had a roughly equal value for the two excitation positions.Conclusion The force hammer testing method is applicable for the modal testing of the three-axis manned centrifuge,ensuring equipment safety and subject comfort.Referen-ces are provided for the following structural optimization design.[Chinese Medical Equipment Journal,2024,45(8):38-43]

Objective To design an adjustable and removable nursing support for dressing patients with lower extremity injuries.Methods The adjustable nursing support was composed of a supporting plate,a cylinder,an upper adjustment mechanism and a lower fixation mechanism.The supporting plate was used to hold the leg of the patient,which had a curved st ruc t u re with a length from 40 to 80 cm;the cylinder was internally snap-fitted with a second slip sleeve to facilitate the adjustment of the support plate;the upper adjustment mechanism mainly consisted of a second sliding bar,a second cross bar and an adjustment plate;the lower fixation mechanism was mainly composed of a first clamping plate and a second clamping plate.Results The adjustable nursing support could be firmly fixed on the sickbed,and its height and angle could be adjusted according to the patient's wound position and subjective comfort.Conclusion The adjustable nursing support gains advantages in safety and patient comfort,and can be used for the dressing of patients with lower extremity injuries.[Chinese Medical Equipment Journal,2024,45(8):110-112]

Objective To design and implement a high-precision ear pulse wave physiological signal detection device for human centrifuge training to solve the problems in measurement and calibration of pilot ear pulse wave signal during human centrifuge training.Methods The high-precision ear pulse wave physiological signal detection device was composed of an ear pulse wave acquisition sensor,a signal acquisition and control unit and a host signal processing module.The ear pulse wave acquisition sensor had an ear-clip-like shape and consisted of an outer shell,an inner shell and an elastic steel plate;the signal acquisition and control unit was made up of an power supply module,a constant voltage module for the light source,a signal acquisition module,a master control module and a data transmission module,which had its software developed with an embedded system;the host signal processing module divided the signal processing into 2 phases of signal pre-processing and pulse wave signal monitoring and display.The detection performance of the device was verified by using a physiological electrical signal calibrator to test the ear pulse wave signals detected with the device;the effectiveness and stability of the device were validated by implementing human centrifuge training experiments with different loads.Results The voltage measurement error,amplitude-frequency characteristics and common mode rejection ratio detected by this device were all within the permitted ranges of JJG 760-2003 Verification Regulation for Electro Cardiac Monitor and JJG 954-2019 Verification Regulation of Digital Electroencephalographs;the device was capable of detecting the ear pulse wave signals of pilot during human centrifuge training in real time with little interference from motion and stable signal quality.Conclusion The device can accurately clarify the changes in the amplitude of the pilot's ear pulse wave during human centrifuge training and effectively reflect the changes in the pilot's cerebral blood flow under positive acceleration.[Chinese Medical Equipment Journal,2024,45(9):35-40]

Insects frequently encounter microbial infections in their natural environment.Infections such as viruses carried by vector arthropods can cause serious human illness or animal epidemics.However,insects rely primarily on their innate immune system to defend themselves against pathogenic infections.Based on its structure and effector mechanisms,the immune system primarily comprises cellular and humoral immunity.Cellular immunity involves phagocytosis,agglutination,and encapsulation,carried out by hemocytes.Humoral immunity mostly depends on immunological proteins generated by adipose cells to protect against infections using antimicrobial peptides or melanization reactions.Antimicrobial peptide synthesis contributed significantly to specific immune signalling pathways including Toll,IMD and JAK/STAT.Studying insects'natural defences would help develop new ways to protect humans and animals from vector-borne diseases.

Objective: This cross-sectional investigation aimed to determine the incidence, clinical characteristics, prognosis, and related risk factors of olfactory and gustatory dysfunctions related to infection with the SARS-CoV-2 Omicron strain in mainland China. Methods: Data of patients with SARS-CoV-2 from December 28, 2022, to February 21, 2023, were collected through online and offline questionnaires from 45 tertiary hospitals and one center for disease control and prevention in mainland China. The questionnaire included demographic information, previous health history, smoking and alcohol drinking, SARS-CoV-2 vaccination, olfactory and gustatory function before and after infection, other symptoms after infection, as well as the duration and improvement of olfactory and gustatory dysfunction. The self-reported olfactory and gustatory functions of patients were evaluated using the Olfactory VAS scale and Gustatory VAS scale. Results: A total of 35 566 valid questionnaires were obtained, revealing a high incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain (67.75%). Females(χ2=367.013, P<0.001) and young people(χ2=120.210, P<0.001) were more likely to develop these dysfunctions. Gender(OR=1.564, 95%CI: 1.487-1.645), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), oral health status (OR=0.881, 95%CI: 0.839-0.926), smoking history (OR=1.152, 95%CI=1.080-1.229), and drinking history (OR=0.854, 95%CI: 0.785-0.928) were correlated with the occurrence of olfactory and taste dysfunctions related to SARS-CoV-2(above P<0.001). 44.62% (4 391/9 840) of the patients who had not recovered their sense of smell and taste also suffered from nasal congestion, runny nose, and 32.62% (3 210/9 840) suffered from dry mouth and sore throat. The improvement of olfactory and taste functions was correlated with the persistence of accompanying symptoms(χ2=10.873, P=0.001). The average score of olfactory and taste VAS scale was 8.41 and 8.51 respectively before SARS-CoV-2 infection, but decreased to3.69 and 4.29 respectively after SARS-CoV-2 infection, and recovered to 5.83and 6.55 respectively at the time of the survey. The median duration of olfactory and gustatory dysfunctions was 15 days and 12 days, respectively, with 0.5% (121/24 096) of patients experiencing these dysfunctions for more than 28 days. The overall self-reported improvement rate of smell and taste dysfunctions was 59.16% (14 256/24 096). Gender(OR=0.893, 95%CI: 0.839-0.951), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), history of head and facial trauma(OR=1.180, 95%CI: 1.036-1.344, P=0.013), nose (OR=1.104, 95%CI: 1.042-1.171, P=0.001) and oral (OR=1.162, 95%CI: 1.096-1.233) health status, smoking history(OR=0.765, 95%CI: 0.709-0.825), and the persistence of accompanying symptoms (OR=0.359, 95%CI: 0.332-0.388) were correlated with the recovery of olfactory and taste dysfunctions related to SARS-CoV-2 (above P<0.001 except for the indicated values). Conclusion: The incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain is high in mainland China, with females and young people more likely to develop these dysfunctions. Active and effective intervention measures may be required for cases that persist for a long time. The recovery of olfactory and taste functions is influenced by several factors, including gender, SARS-CoV-2 vaccination status, history of head and facial trauma, nasal and oral health status, smoking history, and persistence of accompanying symptoms.
Female ; Humans ; Adolescent ; SARS-CoV-2 ; Smell ; COVID-19/complications* ; Cross-Sectional Studies ; COVID-19 Vaccines ; Incidence ; Olfaction Disorders/etiology* ; Taste Disorders/etiology* ; Prognosis

Objective To explore the clinical value of second polar body (Pb2) exclusion monitoring by timelapse in predicting the fertilization and embryo development efficiency for intracytoplasmic sperm injection ( ICSI). Methods A retrospective research was performed on 278 patients treated with ICSI, the clinical data and Time-lapse monitoring embryo culture data were collected and analyzed, to explore the exclusion of Pb2 after ICSI and the relationship between the specific exclusion time and the outcome of fertilization and embryo development. Results The average time of Pb2 exclusion after ICSI was ( 3. 03 ± 1. 21) hours; The fertilization rate, 2 pronucleus(PN) fertilization rate and 5 days ( D5) blastocyst formation rate in the Pb2 exclusion group were significantly higher than those in the without Pb2 exclusion group (99.95% vs f. 75%, P < 0 . 001; 97.18% vs 0.66%, P< 0.001; 60.50% vs 16.67%, P < 0 . 0 5 ) ; The 2PN fertilization rate in Pb2 exclusion time >3-4 hours group was significantly higher than that in 0-2 hours group and >5 hours group (98.80% vs 9 3 . 8 1 % , P<0. 05; 98.80% vs 95.40%, P<0. 0 5 ) ; The exclusion time of Pb2 was significantly correlated with the average number of blastomeres in D3 embryos (P<0. OOf). The D5 blastocyst formation rate of 3-4 hours group was significantly lower than that of > 2-3 hours group ( 56. 23% vs 67. 23%, P < 0. 05 ) , > 4-5 hours group was significantly lower than 0-2 hours group and >2-3 hours group ( 46. 6f % vs 62. 30% , P<0. 05; 46. 6f % vs 67. 23% , P< 0. 05) , and D5 blastocyst formation rate of >5 hours group was 7. f 4 % , which were significantly lower than that of the other four groups (P<0. 05). The fonnation rate of D5 high-quality blastocysts in 3-4 hours group was significantly lower than 0-2 hours group and > 2-3 hours group ( 9. 92% vs 16. 39% , P<0. 05; 9. 92% vs 20. 72% , P<0. 05) , and D5 highquality blastocysts formation rate in > 4-5 hours group was significantly lower than that in > 2-3 hours group (11. 02% vs 20.72%, P<0. 05). Conclusion Monitoring Pb2 exclusion by Time-lapse can accurately predict fertilization outcome. The time of Pb2 exclusion is significantly correlated with embiyo development potential. It is a valuable morphological index to predict fertilization and embiyo development outcome in ICSI.