Objective To prepare virus-like particles (VLPs) for yellow fever virus (YFV) using the pACYCDuet-1 single-plasmid dual expression system. Methods Gene fragments including NS1, NS5, and 5' untranslated region (UTR) and 3' UTR fragment of YFV were cloned into the expression plasmid pACYCDuet-1-MS2-TMpac (carrying MS2 coat protein gene) and transformed into E. coli BL21(DE3) for expression. VLPs were observed by TEM. After DNase I/RNase A digestion, RNA was extracted and transcribed into cDNA, which was subjected to fluorescence quantitative PCR detection. Results According to SN/T 3560-2013, double digestion and colony PCR of pACYCDuet-1-MS2-TMpac-YFV both produced expected bands. SDS-PAGE showed a target band at 25-35 kDa. RT-PCR amplified VLPs after enzyme digestion, and TEM revealed VLPs with clear edges and translucent interiors. Thus, the plasmid was successfully constructed, and the phage coat protein packaged YFV genes with nuclease resistance. Conclusion VLPs containing specific gene fragments of yellow fever virus have been successfully prepared. These nuclease-resistant VLPs can serve as safe and stable quality control materials to ensure the reliability of laboratory detection for YFV.

Objective:To improve the understanding of patients with diffuse large B-cell lymphoma (DLBCL) with pulmonary cryptococcosis.Methods:The clinical data of 1 DLBCL patient with pulmonary cryptococcosis in the Central Hospital of Fengxian District of Shanghai in May 2023 were retrospectively analyzed, and the relevant literatures were reviewed.Results:This 75-year-old female patient was asymptomatic after 2 cycles of R-CHOP chemotherapy. The high-resolution CT of lung showed that lung nodules were progressively enlarged. Antibacterial treatment was ineffective. Pulmonary cryptococcosis was confirmed by bronchoalveolar lavage fluid (BALF) targeted high-throughput sequencing (tNGS) and cryptococcus capsular antigen (CrAg) detection. The central nervous system was not involved. And the long-term adequate-dose fluconazole was prescribed for 6 months, and the treatment against lymphoma was given synchronously. The lung nodule lesions reduced after antifungal therapy for 1 month. The lung nodules disappeared after the follow-up of 6 months after completion of final chemotherapy. The evaluation of lymphoma indicated complete remission.Conclusions:Pulmonary cryptococcosis occurs insidiously and shows no specific symptoms; its imaging manifestations are variable and routine anti-infection is ineffective. Immunochemotherapy for lymphoma patients is a high-risk factor for cryptococcal infection. tNGS and CrAg testing for BALF are effective methods of the confirmed diagnosis. The early and long-term adequate-dose antifungal treatment is the key to preventing the recurrence or progression.

Objective To evaluate the value of ultrasound and magnetic resonance imaging(MRI)in the diagnosis of knee osteoarthritis(KOA)by Meta-analysis.Methods Multiple databases for literature on KOA ultrasound and MRI diagnosis were screened.After data extraction and study quality assessment,14 articles involving 1613 patients were finally included.Meta-analysis were used on the extracted data to comprehensively evaluate the effectiveness of ultrasound and MRI in the diagnosis of KOA.Results All included studies used arthroscopy or surgical pathology as the gold standard for diagnosis.The pooled sensitivity,specificity,and diagnostic odds ratio(DOR)for ultrasound in diagnosing KOA were 0.79,0.82,and 20.30,respectively,with area under the curve(AUC)was 0.89.In comparison,the pooled sensitivity,specificity,and DOR for MRI in diagnosing KOA were 0.88,0.85,and 42.35,respectively,with AUC of 0.92.Conclusion Ultrasound and MRI have good accuracy in the diagnosis of KOA,and MRI is superior to ultrasound.

Objective To evaluate the value of ultrasound and magnetic resonance imaging(MRI)in the diagnosis of knee osteoarthritis(KOA)by Meta-analysis.Methods Multiple databases for literature on KOA ultrasound and MRI diagnosis were screened.After data extraction and study quality assessment,14 articles involving 1613 patients were finally included.Meta-analysis were used on the extracted data to comprehensively evaluate the effectiveness of ultrasound and MRI in the diagnosis of KOA.Results All included studies used arthroscopy or surgical pathology as the gold standard for diagnosis.The pooled sensitivity,specificity,and diagnostic odds ratio(DOR)for ultrasound in diagnosing KOA were 0.79,0.82,and 20.30,respectively,with area under the curve(AUC)was 0.89.In comparison,the pooled sensitivity,specificity,and DOR for MRI in diagnosing KOA were 0.88,0.85,and 42.35,respectively,with AUC of 0.92.Conclusion Ultrasound and MRI have good accuracy in the diagnosis of KOA,and MRI is superior to ultrasound.

Objective:To study the effects of epidermal growth factor(EGF)on the coordinated motor behaviors and changes of nigrostriatal dopaminergic system under the impact of EGF in middle-aged rats.Methods:Healthy aged Sprague Dawley(SD)rats were subcutaneously administered EGF(0.1 mg/ml)in the dorsal region for 7 days.Adhe-sive removal test,tapered beam walking test and descending a wire mesh pole test were performed to detect the changes in the coordinated motor behaviors of rats as well as changes in the expression of tyrosine hydroxylase(TH)and dopa-mine transporter(DAT)of nigrostriatal dopaminergic system in rats.Results:Middle-aged rats showed reduced behav-ioral parameters of adhesive removal test,tapered beam walking test and descending a wire mesh pole test compared with those of adult rats(P<0.05),which were improved after treatment with EGF(P<0.05).The expression of TH and DAT in nigrostriatal dopaminergic system was down-regulated in middle-aged rats compared with that in adult rats(P<0.01),however,which were up-regulated after treatment with EGF(P<0.01).Conclusion:EGF can amelio-rate the decline in coordinated motor behaviors and increases the activity of nigrostriatal dopaminergic system in middle-aged rats.

Objective:To study the effects of epidermal growth factor(EGF)on the coordinated motor behaviors and changes of nigrostriatal dopaminergic system under the impact of EGF in middle-aged rats.Methods:Healthy aged Sprague Dawley(SD)rats were subcutaneously administered EGF(0.1 mg/ml)in the dorsal region for 7 days.Adhe-sive removal test,tapered beam walking test and descending a wire mesh pole test were performed to detect the changes in the coordinated motor behaviors of rats as well as changes in the expression of tyrosine hydroxylase(TH)and dopa-mine transporter(DAT)of nigrostriatal dopaminergic system in rats.Results:Middle-aged rats showed reduced behav-ioral parameters of adhesive removal test,tapered beam walking test and descending a wire mesh pole test compared with those of adult rats(P<0.05),which were improved after treatment with EGF(P<0.05).The expression of TH and DAT in nigrostriatal dopaminergic system was down-regulated in middle-aged rats compared with that in adult rats(P<0.01),however,which were up-regulated after treatment with EGF(P<0.01).Conclusion:EGF can amelio-rate the decline in coordinated motor behaviors and increases the activity of nigrostriatal dopaminergic system in middle-aged rats.

Objective To evaluate the effectiveness of filter membranes made from different materials in monitoring the health status of rodents in barrier environment facilities by investigating their microbial capture performance.Methods Pasteurella pneumotropica(Pp)and Staphylococcus aureus(Sa)were used as representative strains to simulate the process of microbial capture by filter membranes under laboratory conditions.The microbial capture effectiveness of five self-selected filter membranes(M1,M2,M3,M4,and M5)with adsorption and breathability properties and a commercial filter membrane(T1)were comprehensively evaluated based on captured dust mass,minimum detection limit,and differences in Ct values obtained through fluorescence quantitative PCR detection.The best-performing self-selected filter membrane was placed in the ventilation ducts of cage racks within the barrier facility,with sentinel mice in corresponding cage racks as the control group.Staphylococcus epidermidis and Escherichia coli were used as indicator bacteria to calculate the positive detection rate and coincidence rate,thereby exploring the feasibility of using microbial capture filter membranes to monitor the health status of experimental animals in barrier facilities.Results In terms of the captured dust mass,the self-selected filter membrane M3(non-woven filter membrane with a diameter of 0.1 μm);showed a capture effectiveness second only to T1,with a capture mass of 0.126 g.For Sa,all filter membranes except M4 had a minimum detection limit of 102 CFU/g.For Pp,the minimum detection limit for all filter membranes was 102 CFU/g.However,the Ct value of the quantitative fluorescence PCR amplification results for M3 was significantly lower than that of other materials,indicating that M3 had the best capture performance among the five self-selected materials.In the filter detection verification experiment,the positive detection rate of Staphylococcus epidermidis in sentinel mouse feces and M3 was 50.00％(6/12)and 58.33％(7/12),respectively,with a coincidence rate of 92％.The positive detection rate of Escherichia coli in both sentinel mouse feces and M3 was 50.00％(6/12),with a coincidence rate of 100％.Conclusion Among the 5 self-selected filter membranes,M3 exhibits the best capturing performance.Within the barrier environment facilities,M3 outperforms sentinel mice in monitoring Staphylococcus epidermidis.Therefore,non-woven filter membrane with a diameter of 0.1 μm;can be used as the material for microbial capture filter membranes,providing valuable insights for the selection and application of microbial capture filter membranes used in PCR monitoring of cage exhaust air dust.

Objective To explore the effect of exposure to noise of 3.0T magnetic resonance imaging(MRI)on children's cochlear function.Methods We prospectively recruited 72 children who underwent cranial MRI examination at our hospital from May to November 2018;3M earplugs and sponge mats were used for hearing protection during MRI scanning.Noise level(dBA)of each MRI sequence was detected with a nonmagnetic microphone and a sound level meter.Distortion product otoacoustic emissions(DPOAE)test at 2-7 kHz was performed 24 hours before and 30 minutes after the MRI examination.Paired t-test or Wilcoxon signed-rank test was used to analyze differences in DPOAE amplitude before and after the MRI examination.Results The average noise level of MRI measured in the study was(107.7±3.92)dBA.Compared with that before the MRI examination,the DPOAE amplitude(dB)changed little after the MRI examination;the range of amplitude differences in each age group was as follows:left ear(-0.24-1.10)and right ear(-0.24-0.74)in the 0-1 year-old group;left ear(-0.07-0.59)and right ear(-0.57-0.75)in the 2-5 year-old group;left ear(-0.36-0.44)and right ear(-0.30-0.57)in the 6-12 year-old group.No statistically significant difference was found(correction P＞0.05).Conclusion No potential impact of 3.0T MRI noise on children's cochlear function was observed under routine hearing protection.

Objective To explore the key nursing cooperation points in single-port laparoscopic cholecystectomy based on magnetic anchor technique. Methods The general information of 24 patients with transumbilical single-port laparoscopic cholecystectomy based on magnetic anchor technique was analyzed. Combined with the surgical procedure, the key nursing cooperation points of this innovative surgery were analyzed from the perspective of operating room nurses. Results By learning the principles of magnetic anchor technique before surgery, understanding the usage and precautions of the magnetic anchor device, accurately passing the magnetic anchor device during surgery, and avoiding mutual interference between the magnetic anchor device and conventional surgical instruments, the operating room nurses successfully assisted the surgeons in completing 24 cases of transumbilical single-port laparoscopic cholecystectomy based on magnetic anchor technique. Conclusion Real-time understanding of the surgeon's operation progress during surgery, accurate delivery of instruments, and avoidance of interference between the magnetic anchor device and conventional surgical instruments are important factors in the nursing cooperation of this surgical procedure.

Objective To investigate the feasibility of the optimally designed"I"shaped structure mag-net based on the principle of magnetic compression technique for the preparation of rectovaginal fistula animal model.Methods Using 10 New Zealand female rabbits as the model animals,two self-designed magnets were inserted through the vagina and anus respectively after anesthesia,and the two magnets were adjusted to the appropriate position and made them attraction each other to form a magnet-rectovaginal partition-magnet structure.When the compression tissue between the magnets became ischemic necrosis and fell off,the two magnets formed the"1"shape structure and were located in the stoma of rectovaginal fistula to prevent the stoma from becoming smaller or even closing itself.The operation time and rectovaginal fistula formation time were recorded.The experimental rabbits were killed in postoperative 2 weeks,and the rectovaginal fistula specimens were obtained.The formation of fistula orifice was observed and the size of fistula orifice was meas-ured.Results The animal model of rectovaginal fistula was successfully prepared in all 10 experimental rab-bits.The procedure of intraoperative magnet placement was smooth and the operation time was(1.55±0.65)min.The experimental animals were generally in good condition after surgery,and the fistula orifice was formed on postoperative(4.80±0.75)d.After taking the gross specimen of rectovaginal septum in postopera-tive 2 weeks,the magnet was removed.The fistula orifice of rectovaginal fistula was visible with the diameter of(5.86±0.38)mm.Conclusion The"I"shaped structure magnet designed based on the principle of mag-netic compression technique could be used in the preparation of the rectovaginal fistula animal model.Its oper-ation is simple with high success rate of model preparation and good uniformity in fistula orifice.