Staphylococcus aureus is a Gram-positive bacterium with strong pathogenicity. With the widespread use of antibiotics， its multi-drug resistance has gradually increased. Among them， methicillin-resistant S. aureus （MRSA） is one of the main pathogens of hospital and community infections. Antimicrobial peptides are short-chain peptides with good antibacterial effects and low drug resistance， which have been widely studied in recent years. This study summarizes the mechanism of action of antimicrobial peptides and related study on antimicrobial peptides against MRSA from different sources. It is found that the mechanisms of action of antimicrobial peptides include targeting bacterial cell membranes， bacterial cells， and bacterial cell walls， etc. Besides isolating antimicrobial peptides with anti-MRSA activity from animals， plants， and microorganisms， antimicrobial peptides can also be obtained through synthetic methods. Among them， GHa-derived peptides from animal sources， Ib-AMP4 from plant sources， Ph-SA from microbial sources， the synthetic peptide LLKLLLKLL-NH2， and so on， due to their effective antibacterial activity， rapid bactericidal speed， and low toxicity， are promising candidates for anti-MRSA drugs.

Objective To establish and evaluate a rapid detection method for SARS-CoV-2 based on reverse transcriptase-recombinase aided amplification(RT-RAA)combined with the clustered regularly interspaced short palindromic repeats(CRISPR)/Cas12a system.Methods RT-RAA primers and CRISPR-derived RNA(crRNA)were designed based on the nucleocapsid(N)gene of SARS-CoV-2 from NCBI database.The detection system was optimized with magnesium acetate(MgAc)concentration,RT-RAA reaction tempera-ture and time and LbCas12a reaction temperature.The sensitivity and specificity of the method were evaluated using recombinant plas-mids(100-106 copies/μL)and other respiratory pathogens.The RT-RAA-CRISPR/Cas12a method was compared with RT-PCR by tes-ting 70 clinical samples in parallel.Results The optimized RT-RAA-CRISPR/Cas12a assay could detect SARS-CoV-2 within 50 min at 37 ℃.The limit of detection was 10 copies/μL for the fluorescence-based method and 1×102 copies/μL for the lateral flow assay.The method specifically detected SARS-CoV-2 without cross-reactivity to other respiratory pathogens.The results of testing 70 clinical samples using RT-RAA-CRISPR/Cas12a showed agreement of 100％with those of RT-PCR.Conclusion The established RT-RAA-CRISPR/Cas12a assay for SARS-CoV-2 detection is rapid,cost-effective,highly sensitive and specific.It can be performed by less experienced personnel and no expensive equipment is required,thus it may provide a new approach for rapid clinical diagnosis and large-scale on-site screening of SARS-CoV-2.

Platelets contribute to maintaining brain homeostasis in a physiological environment,and platelet dysfunction is closely associated with the occurrence of many diseases,including neurodegenerative diseases.This article provides a comprehensive summary of the various functions of platelets and their role in the occurrence and development of one specific neurodegenerative disease,Parkinson's disease.It discusses the correlation between platelet functional status and Parkinson's disease pathology,the potential and possible clinical significance of platelet heterogeneity as a peripheral biomarker for Parkinson's disease diagnosis and prognosis,as well as the therapeutic potential of healthy platelets in Parkinson's disease.

Objective:To evaluate the effect of transcutaneous auricular vagus nerve stimulation (taVNS) on tourniquet-induced hypertension (TIH) in the patients undergoing anterior cruciate ligament reconstruction.Methods:Seventy-four patients of either sex, aged 18-60 yr, of American Society of Anesthesiologists Physical Status classification I or II, with body mass index of 18-30 kg/m 2, undergoing elective anterior cruciate ligament reconstruction under general anesthesia combined with preoperative femoral nerve block, were divided into 2 groups ( n=37 each) using a random number table method: sham stimulation group (group SS) and group taVNS. Group SS received stimulation on the ear lobe and the tail of the helix of the left ear. Group taVNS received stimulation on the cymba concha and the earlobe of the left ear. Both groups received stimulation from 1 h before induction of anesthesia until the end of the procedure (frequency of 30 Hz, pulse width of 300 μs, and amplitude of the strongest current that could be tolerated by the patient in the absence of pain). The tourniquet inflation pressure was 280 mmHg, with an inflation time of 60-90 min. Systolic blood pressure, diastolic blood pressure and heart rate were recorded before tourniquet inflation to assess the development of intraoperative TIH. The consumption of intraoperative propofol, remifentanil, nitroglycerin, esmolol, norepinephrine and atropine was recorded, and the occurrence of postoperative nausea and vomiting, skin itching and headache and dizziness was also recorded. Results:Compared with group SS, the incidence of TIH and the number of patients used nitroglycerin were significantly reduced ( P<0.05), and no significant changes were found in the other parameters in group taVNS ( P>0.05). Conclusions:taVNS can decrease the occurrence of TIH in the patients undergoing anterior cruciate ligament reconstruction.

【Objective】 To evaluate the safety and efficacy of modified ultrasound-guided needle-like visible nephroscope (Needle perc) holmium laser lithotripsy in the treatment of 1-2 cm calyceal calculi, and provide a reference for the selection of clinical treatment methods. 【Methods】 The clinical data of 60 patients with single intrarenal calyceal calculi (the largest diameter 1~2 cm) treated in our hospital during Jan.2022 and May 2023 were retrospectively analyzed.The patients were divided into ureteroscopic holmium laser lithotripsy group (flexible ureteroscope group) and Needle perc group, with 30 patients in either group.The clinical data of the two groups were compared. 【Results】 Compared with the flexible ureteroscope group, the Needle perc group had shorter overall hospitalization time [(3.00±1.25) d vs. (4.00±1.25) d], shorter operation time [(44.63±5.42) min vs. (48.50±7.24) min], lower hospitalization expenses [(15 518±441) yuan vs. (16 872±903) yuan], higher stone-clearance rate [93.3% (28/30) vs. 50.7% (15/30), P<0.001], less increase of procalcitonin after operation [(0.02±0.01) vs. (0.12±0.18), P=0.007], and lower incidence of complications [3.3% (1/30) vs. 26.7% (8/30), P=0.030]. 【Conclusion】 The modified ultrasound-guided Needle perc holmium laser lithotripsy is safe and effective in the treatment of 1-2 cm lower calyceal calculi, with high stone removal rate and low complication rate.

Background Based on numerous epidemiological studies, radionuclide ¹³¹I can result in thyroid disease. Objective To study the contamination level of thyroid ¹³¹I in ¹³¹I treatment associated radiation workers in nuclear medicine departments in Shanghai. Methods Based on a general survey on basic situation of nuclear medicine in Shanghai, the level of internal exposure of radiation workers involved in ¹³¹I treatment was assessed with questionnaires and on-site monitoring. A portable γ spectrometer was used for on-site detection, the intake and annual effective dose were estimated according to the measurement results. Physical examination reports were collected for radionuclide positive workers, and chromosome testing was performed. Results There were 579 nuclear medicine workers and 175 were engaged in ¹³¹I treatment in Shanghai. ¹³¹I was detected in thyroid of 18 workers, with a detection rate of 10.3%. Among them, the detection rates of thyroid ¹³¹I in nurses and cleaners were 23% and 25% respectively. The mean measured activity of thyroid ¹³¹I was 306.1 Bq and the maximum measured activity was 3716.9 Bq (nurse). The maximum intake was estimated at 37544 Bq and the median was 786.4 Bq. The average annual committed effective dose was 1.22 mSv and the maximum value was 14.87mSv. The chromosomal aberration rates of all detected workers were negative, and all blood indicators were normal except one with low hemoglobin. Conclusion The annual dose of nuclear medical staff engaged in ¹³¹I treatment does not exceed the national standard limit, but the internal exposure of nurses and cleaners should not be ignored. On the basis of strengthening protection and decontamination, routine internal exposure monitoring should be carried out.

Humans ; Asthma/drug therapy* ; Biological Therapy

Hepatocellular carcinoma(HCC) is one of the most common malignancies of the digestive system,which is prone to be associated with microvascular or macrovascular invasion. Among them,HCC with inferior vena cava tumor thrombus(IVCTT) or right atrium tumor thrombus(RATT) is rare and has a poor prognosis. However,surgical treatment of HCC with IVCTT and (or) RATT is rarely reported and summarized. The review described the classification of HCC tumor thrombus with IVCTT and (or) RATT, summarized the progress of surgical approaches and surgical operations,and introduced a case of thrombectomy after pushing from the outer surface of the atrium,rendering the RATT to the inferior vena cava under non-cardiopulmonary bypass. The review also proposed the prospective treatments for HCC with IVCTT or RATT,providing clinical guidance to hepatobiliary surgeons.

The limited coverage of soft tissue and complex biomechanical factors make resection and reconstruction of distal tibial tumors extremely challenging. Megaprosthesis can provide good mechanical strength for tumor en bloc resection, but there are many postoperative complications, and the problems of insufficient soft tissue coverage and postoperative ankle instability must be solved. The development of three-dimensional digital technology may provide a new treatment strategy for distal tibial reconstruction. Compared to ankle joint preservation endoprostheses, the rapid osseointegration effect of three dimensional-printed megaprosthesis with ankle arthrodesis provides better ankle joint stability and postoperative function. In addition, the three dimensional-printed megaprosthesis may improve complications such as insufficient soft tissue coverage and talus collapse by reducing the circumference of the prosthesis and matching it with the talus through personalized design. Of course, there are few research reports on distal tibial prostheses, and the safety of three dimensional-printed megaprosthesis with ankle arthrodesis needs to be confirmed through extensive long-term follow-up studies. The selection of proximal and distal fixation methods for prostheses needs to be explored in future research.