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.

Guided by the concept of quality by design(QbD), this study optimizes the calcination and quenching process of calcined Magnetitum and establishes the XRD characteristic spectra of calcined Magnetitum, providing a scientific basis for the formulation of quality standards. Based on the processing methods and quality requirements of Magnetitum in the Chinese Pharmacopoeia, the critical process parameters(CPPs) identified were calcination temperature, calcination time, particle size, laying thickness, and the number of vinegar quenching cycles. The critical quality attributes(CQAs) included Fe mass fraction, Fe~(2+) dissolution, and surface color. The weight coefficients were determined by combining Analytic Hierarchy Process(AHP) and the criteria importance though intercrieria correlation(CRITIC) method, and the calcination process was optimized using orthogonal experimentation. Surface color was selected as a CQA, and based on the principle of color value, the surface color of calcined Magnetitum was objectively quantified. The vinegar quenching process was then optimized to determine the best processing conditions. X-ray diffraction(XRD) was used to establish the characteristic spectra of calcined Magnetitum, and methods such as similarity evaluation, cluster analysis, and orthogonal partial least squares-discriminant analysis(OPLS-DA) were used to evaluate the quality of the spectra. The optimized calcined Magnetitum preparation process was found to be calcination at 750 ℃ for 1 h, with a laying thickness of 4 cm, a particle size of 0.4-0.8 cm, and one vinegar quenching cycle(Magnetitum-vinegar ratio 10∶3), which was stable and feasible. The XRD characteristic spectra analysis method, featuring 9 common peaks as fingerprint information, was established. The average correlation coefficient ranged from 0.839 5-0.988 1, and the average angle cosine ranged from 0.914 4 to 0.995 6, indicating good similarity. Cluster analysis results showed that Magnetitum and calcined Magnetitum could be grouped together, with similar compositions. OPLS-DA discriminant analysis identified three key characteristic peaks, with Fe_2O_3 being the distinguishing component between the two. The final optimized processing method is stable and feasible, and the XRD characteristic spectra of calcined Magnetitum was initially established, providing a reference for subsequent quality control and the formulation of quality standards for calcined Magnetitum.
X-Ray Diffraction/methods* ; Drugs, Chinese Herbal/chemistry* ; Quality Control ; Particle Size

Incomplete debridement of chronic osteomyelitis is the main factor leading to recurrence. For the treatment of chronic osteomyelitis, the complete elimination of the source of infection is the key to preventing recurrence. This process includes not only the complete removal of infected lesions, dead bone, accreted scar tissue and granulation tissue, but also the elimination of dead space and improved local blood circulation. In these steps, debridement is a core procedure, and judging the scope of debridement is the premise of whether it could be completely debridement. This article systematically reviewed the application of different imaging techniques in evaluating the scope of chronic osteomyelitis infection, and discusses its future development trend. Although traditional plain X-ray film could preliminarily indicate osteomyelitis, it is difficult to determine the infection scope. CT scan has the function of accurate anatomic localization, which is important for preoperative assessment of the scope of bone infection, but the recognition of soft tissue information is limited. MRI, with its high sensitivity, clearly distinguishes between infected bone and soft tissue, which plays an important role in the evaluation of soft tissue infection, but may overestimate the extent of bone infection. Nuclide techniques such as 18F-FDG PET/CT and SPECT/CT show great potential for accurately assessing the extent of infection before surgery. In the future, by optimizing the combination of different imaging technologies, combining clinical symptoms, intraoperative conditions and pathological results, and developing an image analysis platform based on artificial intelligence, it will be able to more accurately assess the scope of infection, provide more effective and personalized treatment plans for patients with chronic osteomyelitis, enhance treatment effects, and significantly improve quality of life of patients.
Humans ; Osteomyelitis/diagnosis* ; Chronic Disease ; Magnetic Resonance Imaging ; Tomography, X-Ray Computed

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

Objective:To establishment an assay for HIV-1 intact proviral DNA assay through droplet digital PCR (ddPCR).Methods:DNA was extracted by culturing 8E5 cells, a Tlymphocyte cell line containing a single copy of integrated HIV-1 provirus. Serial diluting DNA were prepared by amplified 1-fold, 5-fold, 25-fold, 625-fold, 3 125-fold, and 15 625-fold across the HIV-1 Ψ region, env region, and eukaryotic chromosome 10 RPP30 regions, and the linear relationship was calculated and the minimum detection concentration. DNA solution of 5 μl, 3.1 μl, 2.5 μl was added to the ddPCR mixture respectively, with each dilution undergoing two batches of detection, and each was repeated four times. The intra-batch variation coefficient was detected, while the inter-batch variation coefficient was detected by the same DNA amount and different DNA amounts to determine the stability; 8E5 cell was used to detect the intact proviral content in cells.Results:The linear fitting goodness of Ψ region, env region and RPP30 region are R2≥0.999, R2≥0.993, R2≥0.996 in 6 dilutions of DNA, respectively. At a 3 125-fold dilution, the lowest positive droplets were detected in the Ψ region, env region and RPP30 region were 3, 2 and 2, respectively, the detected concentrations were 2.37 copies/μl, 1.21 copies/μl and 1.58 copies/μl. The ddPCR repeatability experimental detecting DNA showed that the Ψ region of the intra-batch variation coefficients ranged from 0.66% to 3.43%, with the inter-batch variation coefficients of the same DNA at 3.19%, 4.3% and 3.45% respectively, and the inter-batch variation coefficients of the different DNA at only 4.35%. The env region of the intra-batch variation coefficients ranged from 0.7% to 3.20%, with the inter-batch variation coefficients of the same DNA at 3.18%, 4.52% and 3.4% respectively, and the inter-batch variation coefficients of the different DNA at only 4.02%. The RPP30 region of the intra-batch variation coefficients ranged from 0.91% to 2.91%, with the inter-batch variation coefficients of the same DNA at 3%, 4.55% and 3.37% respectively, and the inter-batch variation coefficients of the different DNA at only 3.98%. The proportion of 8E5 cells containing defective provirus and the proportion of intact provirus were calculated to be approximately 90% and 45%, respectively. Conclusions:Droplet digital PCR used to detect HIV-1 intact proviral DNA, showed strong stability and provided a technical means for HIV-1 infection reservoir detection.

Important forensic diagnostic indicators of sudden death in coronary atherosclerotic heart dis-ease,such as acute or chronic myocardial ischemic changes,sometimes make it difficult to locate the ischemic site due to the short death process,the lack of tissue reaction time.In some cases,the de-ceased died of sudden death on the first-episode,resulting in difficulty for medical examiners to make an accurate diagnosis.However,clinical studies on coronary instability plaque revealed the key role of coronary spasm and thrombosis caused by their lesions in sudden coronary death process.This paper mainly summarizes the pathological characteristics of unstable coronary plaque based on clinical medi-cal research,including plaque rupture,plaque erosion and calcified nodules,as well as the influencing factors leading to plaque instability,and briefly describes the research progress and technique of the atherosclerotic plaques,in order to improve the study on the mechanism of sudden coronary death and improve the accuracy of the forensic diagnosis of sudden coronary death by diagnosing different patho-logic states of coronary atherosclerotic plaques.

Microplastics(MPs)and nanoplastics(NPs)have become hazardous materials due to the massive amount of plastic waste and disposable masks,but their specific health effects remain uncertain.In this study,fluorescence-labeled polystyrene NPs(PS-NPs)were injected into the circulatory systems of mice to determine the distribution and potential toxic effects of NPs in vivo.Interestingly,whole-body imaging found that PS-NPs accumulated in the testes of mice.Therefore,the toxic effects of PS-NPs on the reproduction systems and the spermatocytes cell line of male mice,and their mechanisms,were investigated.After oral exposure to PS-NPs,their spermatogenesis was affected and the spermatogenic cells were damaged.The spermatocyte cell line GC-2 was exposed to PS-NPs and analyzed using RNA sequencing(RNA-seq)to determine the toxic mechanisms;a ferroptosis pathway was found after PS-NP exposure.The phenomena and indicators of ferroptosis were then determined and verified by ferroptosis inhibitor ferrostatin-1(Fer-1),and it was also found that nuclear factor erythroid 2-related factor 2(Nrf2)played an important role in spermatogenic cell ferroptosis induced by PS-NPs.Finally,it was confirmed in vivo that this mechanism of Nrf2 played a protective role in PS-NPs-induced male reproductive toxicity.This study demonstrated that PS-NPs induce male reproductive dysfunction in mice by causing spermatogenic cell ferroptosis dependent on Nrf2.

Purpose::Vibrio vulnificus ( V. Vulnificus) infection is characterized by rapid onset, aggressive progression, and challenging treatment. Bacterial resistance poses a significant challenge for clinical anti-infection treatment and is thus the subject of research. Enhancing host infection tolerance represents a novel infection prevention strategy to improve patient survival. Our team initially identified cytochrome P4501A1 (CYP1A1) as an important target owing to its negative modulation of the body's infection tolerance. This study explored the superior effects of the CYP1A1 inhibitor bergamottin compared to antibiotic combination therapy on the survival of mice infected with multidrug-resistant V. Vulnificus and the protection of their vital organs. Methods::An increasing concentration gradient method was used to induce multidrug-resistant V. Vulnificus development. We established a lethal infection model in C57BL/6J male mice and evaluated the effect of bergamottin on mouse survival. A mild infection model was established in C57BL/6J male mice, and the serum levels of creatinine, urea nitrogen, aspartate aminotransferase, and alanine aminotransferase were determined using enzyme-linked immunosorbent assay to evaluate the effect of bergamottin on liver and kidney function. The morphological changes induced in the presence of bergamottin in mouse organs were evaluated by hematoxylin and eosin staining of liver and kidney tissues. The bacterial growth curve and organ load determination were used to evaluate whether bergamottin has a direct antibacterial effect on multidrug-resistant V. Vulnificus. Quantification of inflammatory factors in serum by enzyme-linked immunosorbent assay and the expression levels of inflammatory factors in liver and kidney tissues by real-time quantitative polymerase chain reaction were performed to evaluate the effect of bergamottin on inflammatory factor levels. Western blot analysis of IκBα, phosphorylated IκBα, p65, and phosphorylated p65 protein expression in liver and kidney tissues and in human hepatocellular carcinomas-2 and human kidney-2 cell lines was used to evaluate the effect of bergamottin on the nuclear factor kappa-B signaling pathway. One-way ANOVA and Kaplan-Meier analysis were used for statistical analysis. Results::In mice infected with multidrug-resistant V. Vulnificus, bergamottin prolonged survival ( p = 0.014), reduced the serum creatinine ( p = 0.002), urea nitrogen ( p = 0.030), aspartate aminotransferase ( p = 0.029), and alanine aminotransferase ( p = 0.003) levels, and protected the cellular morphology of liver and kidney tissues. Bergamottin inhibited interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α expression in serum (IL-1β: p = 0.010, IL-6: p = 0.029, TNF-α: p = 0.025) and inhibited the protein expression of the inflammatory factors IL-1β, IL-6, TNF-α in liver (IL-1β: p = 0.010, IL-6: p = 0.011, TNF-α: p = 0.037) and kidney (IL-1β: p = 0.016, IL-6: p = 0.011, TNF-α: p = 0.008) tissues. Bergamottin did not affect the proliferation of multidrug-resistant V. Vulnificus or the bacterial load in the mouse peritoneal lavage fluid ( p = 0.225), liver ( p = 0.186), or kidney ( p = 0.637). Conclusion::Bergamottin enhances the tolerance of mice to multidrug-resistant V. Vulnificus infection. This study can serve as a reference and guide the development of novel clinical treatment strategies for V. Vulnificus.

Silver nanoparticles(AgNPs)is widely used in biomedicine,daily chemicals,food industry and other fields,and the possible negative health effects of its exposure have attracted widespread attention.Accurate analysis of AgNPs in biological matrices is the basis for biosafety studies of AgNPs.Among the existing analytical techniques,single particle-inductively coupled plasma-mass spectrometry(sp-ICP-MS)has significant advantages such as high sensitivity and simultaneous detection of different forms of silver.However,AgNPs in biological matrices is uniquely highly dynamic and low in content,and the matrix interference is severe,which increases the complexity of the analysis.Although some scholars have reviewed the application of this method for detection of metal nanoparticles in different scenarios,there is a lack of a summary of the quality control and optimization of the whole process from the perspective of AgNPs detection.There is still a lack of reference standards for the sp-ICP-MS analysis of AgNPs in biological matrices,and the existing methods need to be summarized and further optimized to achieve accurate quantification.Therefore,this paper reviewed the recent studies on the analysis of silver-containing nanoparticles in biological matrices based on sp-ICP-MS,mainly included the principles of the technique,the extraction methods of the particles,and the process of data processing,which focused on elaborating and comparing different pre-treatment methods,and explored issues of the current application of sp-ICP-MS for detection of AgNPs in biological tissues and the development of future optimization trends.The current problems of sp-ICP-MS for detection of AgNPs in biological tissues and the future development trend were also discussed.

Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75％(27/36);boys accounted for 64％(23/36).Among the 36 neonates,31(86％)had disease onset within 3 days after birth,and 19(53％)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61％)had left cerebral infarction and 13(36％)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75％)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72％)and seizures in 10 neonates(34％).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33％,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44％(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.