The growth of three plague phages from Qinghai Plateau in two Yersinia pestis strains(plague vaccine strains EV76 and 614F)and four non-Yersinia pestis strains(Yersinia pseudotuberculosis PTB3,PTB5,Escherichia coli V517,and Yersinia enterocolitica 52302-2)were detected through a micromethod based on the OmniLogTM microbial identification system and by the drop method,to provide a scientific basis for future ecological studies and classification based on the host range.For plague vaccine strains EV76 and 614F,successful phage infection and subsequent phage growth were observed in the host bacte-rium.Diminished bacterial growth and respiration and a concomitant decrease in color were observed with the OmniLogTM mi-crobial identification system at 33 ℃ for 48 h.Yersinia pseudotuberculosis PTB5 was sensitive to Yersinia pestis phage 476,but Yersinia pseudotuberculosis PST5 was insensitive to phage 087 and 072204.Three strains of non-Yersinia pestis(Yersinia pseudotuberculosis PTB3,Escherichia coli V517,and Yersinia enterocolitica 52302-2)were insensitive to Yersinia pestis pha-ges 087,072204,and 476 showed similar growth curves.The growth of phages 476 and 087,as determined with the drop method,in two Yersinia pestis strains(plague vaccine strains EV76 and 614F)and four non-Yersinia pestis strains(Yersinia pseudotuberculosis PTB3,Escherichia coli V517,and Yersin-ia enterocolitica 52302-2)showed the same results at 37 ℃,on the basis of comparisons with the OmniLogTM microbial i-dentification system;in contrast,phages 072204 did not show plaques on solid medium at 37 ℃ with plague vaccine strains EV76 and 614F.Determination based on the OmniLogTM detection system can be used as an alternative to the traditional determination of the host range,thus providing favorable application val-ue for determining the interaction between the phage and host bacteria.

Objective To investigate the dynamic expression with the time change of N6-methyladenosine(m6A)methylation-related factors in the repair process of skeletal muscle injury and its mechanism in the inflammatory response of macrophage in the injure process.Methods In vivo mice models of BaCl2 injury in the gastrocnemius were established.Four mice per group in the control group and injury group.Gastrocnemius tissues were harvested at day 1,3,5,7,and 9 after injury for experiments.Primary gastrocnemius muscle tissue cells,muscle satellite cells,muscle cells,and cell line C2C12 cells were treated with dexamethasone(DEX,50 μmol/L)to mimic injury.Lipopolysaccharide(LPS,100 μg/L)induced RAW264.7 cell lines to mimic the inflammatory response after skeletal muscle injury,and STM2457(30 μmol/L)was added to inhibit the effect of methyltransferase 3(Mettl3)before LPS treatment.The expression of m6A methylation-related factors(Writers,Erasers,Readers)and inflammation factors were detected by Real-time PCR and Western blotting.Results The muscle fibers were dissolved and then gradually repaired with the extension of injury time,the number of monocytes/macrophages increased first and then decreased,and the Pax7 mRNA level increased first and then decreased with the change of injury time.Compared with the control group,the mRNA and protein levels of m6A methylation-related factors in gastrocnemius did not change significantly on the injury-1 day.However,they were significantly increased on the injury-3 days compared with the control group(P＜0.05),and then obviously decreased on the injury-5 days group compared with the injury-3 days group(P＜0.05).Compared with the control group,they were no significant differences on the injury-7 days group and-9 days group.In vitro DEX decreased the mRNA levels of m6A methyltransferase factors in primary muscle satellite cells and C2C12 cells and increased the mRNA expression level of methylation-recognition enzyme factors(P＜0.05).The mRNA levels of m6A methylation-related factors increased significantly in skeletal muscle tissue cells and myocytes after DEX treatment(P＜0.05).After LPS treatment,the mRNA and protein expression levels of m6A methylation-related factors and the mRNA expression levels of inflammatory factors interleukin(IL)-6 and IL-1β in macrophages increased significantly(P＜0.05),while the levels of IL-6 and IL-1β mRNA in macrophages decreased significantly when the Mettl3 was inhibited(P＜0.05).Conclusion m6A methylation-related factors primarily is activated in the damaged muscle cells and inflammation response of macrophages.Inhibition of m6A methyltransferase can reduce the inflammatory response of macrophages.

The development status quo of Shanghai's medical device industry was described.By using SWOT analysis method the influencing factors of the industry were analyzed and the key influencing factors were determined.A SWOT strategy matrix was constructed with considerations on the strengths,weaknesses,opportunities and threats of the key influencing factors.Some suggestions were put forward based on the SWOT strategy matrix and weak links of Shanghai's medical device industry to promote the development of the industry,and references were provided for the development of Shanghai's medical device industry.[Chinese Medical Equipment Journal,2024,45(6):77-82]

Objective To observe the effects of melatonin on autophagy in cortical neurons of neonatal rats with hypoxic-ischemic brain damage(HIBD)and to explore its mechanisms via the PI3K/AKT signaling pathway,aiming to provide a basis for the clinical application of melatonin.Methods Seven-day-old Sprague-Dawley neonatal rats were randomly divided into a sham operation group,an HIBD group,and a melatonin group(n=9 each).The neonatal rat HIBD model was established using the classic Rice-Vannucci method.Neuronal morphology in the neonatal rat cerebral cortex was observed with hematoxylin-eosin staining and Nissl staining.Autophagy-related protein levels of microtubule-associated protein 1 light chain 3(LC3)and Beclin-1 were detected by immunofluorescence staining and Western blot analysis.Phosphorylated phosphoinositide 3-kinase(p-PI3K)and phosphorylated protein kinase B(p-AKT)protein expression levels were measured by immunohistochemistry and Western blot.The correlation between autophagy and the PI3K pathway in the melatonin group and the HIBD group was analyzed using Pearson correlation analysis.Results Twenty-four hours post-modeling,neurons in the sham operation group displayed normal size and orderly arrangement.In contrast,neurons in the HIBD group showed swelling and disorderly arrangement,while those in the melatonin group had relatively normal morphology and more orderly arrangement.Nissl bodies were normal in the sham operation group but distorted in the HIBD group;however,they remained relatively intact in the melatonin group.The average fluorescence intensity of LC3 and Beclin-1 was higher in the HIBD group compared to the sham operation group,but was reduced in the melatonin group compared to the HIBD group(P<0.05).The number of p-PI3K+and p-AKT+cells decreased in the HIBD group compared to the sham operation group but increased in the melatonin group compared to the HIBD group(P<0.05).LC3 and Beclin-1 protein expression levels were higher,and p-PI3K and p-AKT levels were lower in the HIBD group compared to the sham operation group(P<0.05);however,in the melatonin group,LC3 and Beclin-1 levels decreased,and p-PI3K and p-AKT increased compared to the HIBD group(P<0.05).The correlation analysis results showed that the difference of the mean fluorescence intensity of LC3 and Beclin-1 protein in the injured cerebral cortex between the melatonin and HIBD groups was negatively correlated with the difference of the number of p-PI3K+and p-AKT+cells between the two groups(P<0.05).Conclusions Melatonin can inhibit excessive autophagy in cortical neurons of neonatal rats with HIBD,thereby alleviating HIBD.This mechanism is associated with the PI3K/AKT pathway.

Objective To investigate the preliminary clinical effect of closed reduction and cannulated nail internal fixa-tion for femoral neck fracture assisted by robot navigation and positioning system.Methods From July 2019 to January 2020,16 cases of femoral neck fracture(navigation group)were treated with closed reduction and internal fixation guided by robot system,including 7 males and 9 females,aged 25 to 72 years old with an average of(53.61±5.45)years old;Garden classification of fracture:3 cases of type Ⅰ,3 cases of type Ⅱ,8 cases of type Ⅲ,2 cases of type Ⅳ.Non navigation group(control group):20 cases of femoral neck fracture were treated with closed reduction and hollow nail internal fixation,8 males and 12 females,aged 46 to 70 years old with an average of(55.23±4.64)years old;Garden type Ⅰ in 2 cases,type Ⅱ in 4 cases,type Ⅲ in 11 cases,type Ⅳ in 3 cases.The operation time,fluoroscopy times,guide needle drilling times,screw adjustment times,intraoperative bleeding volume and other indicators of two groups were evaluated.Results Both groups were followed up for 12 to 18 months with an average of(15.6±2.8)months.The fractures of both groups were healed without delayed union and nonunion.There was no significant difference in healing time between two groups(P=0.782).There was no significant differ-ence in Harris scores between two groups at the last follow-up(P=0.813).There was no significant difference in operation time between two groups(P＞0.05).There were significant differences between two groups in fluoroscopy times,guide needle drilling times,hollow screw replacement times,and intraoperative bleeding volume(P＜0.05).Conclusion Closed reduction and hollow screw internal fixation assisted by robot navigation system for femoral neck fracture has the advantages of minimally invasive operation,precise screw placement,and reduction of X-ray radiation damage during operation.

Objective To compare clinical efficacy of robot-assisted(RA)and remote sensing navigation alignment(RSNA)system-assisted total knee arthroplasty(TKA).Methods From March 2023 to June 2023,60 patients who underwent the first unilateral TKA due to severe knee osteoarthritis(KOA)were admitted and divided into RSNA group and RA group according to different treatment methods,with 30 patients in each group.There were 5 males and 25 females in RSNA group,aged from 56 to 81 years old with an average of(66.33±7.16)years old;body mass index(BM1)ranged from 19.87 to 38.54 kg·m-2 with an average of(28.40±6.18)kg·m-2;the courses of disease ranged from 5 to 36 months with an average of(18.20±8.98)months;RSNA system was used to assist the positioning of osteotomy.There were 7 males and 23 females in RA group,aged from 55 to 82 years old with an average of(67.83±8.61)years old;BMI ranged from 19.67 to 37.25 kg·m-2 with an aver-age of(28.01±4.89)kg·m-2;the courses of disease ranged from 3 to 33 months with an average of(17.93±9.20)months;RA was performed.Operation time,incision length,latent blood loss at 2 weeks after operation and incidence of lower extremity thrombosis were compared between two groups.Hip-knee ankle angle(HKAA),HKAA deviation,lateral distal femoral angle(LDFA),medial proximal tibial angle(MPTA)and posterior tibial slope(PTS)were compared between two groups;Western Ontario McMaster Universities Osteoarthritis Index(WOMAC)and Knee Society score(KSS)were used to evaluate functional recovery before operation,3 and 6 months after operation.Results The operation was performed successfully in both groups,and there were no serious complications such as vascular and nerve injury during operation.The wound healed well at stage Ⅰafter operation,and the follow-up time was 6 months.The operation time,latent blood loss at 2 weeks after operation and inci-sion length in RSNA group were(94.35±5.75)min,(130.54±17.53)mland(14.73±2.14)cm,respectively;while(102.57±6.88)min,(146.33±19.47)ml and(16.78±2.32)cm in RA group,respectively.RSNA group was better than RA group(P＜0.05).No deep vein thrombosis occurred in both groups at 2 weeks after operation,5 patients occurred intermuscular vein throm-bosisin in RSNA group and 8 patients in RA group,the difference was not statistically significant(P＞0.05).In RSNA group,HKAA,LDFA and MPTA were(173.00±5.54)°,(86.96±3.45)°,(82.79±3.35)° before operation,and(178.34±1.85)°,(89.92±0.42)°,(89.84±0.73)° at 1 week after operation,respectively.In RA group,HKAA,LDFA and MPTA were(173.31±6.48)°,(87.15±3.40)° and(82.99±3.05)° before operation,and(178.52±1.79)°,(90.03±0.39)° and(90.15±0.47)° at 1 week after operation,respectively.HKAA,LDFA and MPTA were significantly improved in both groups at 1 week after oper-ation(P＜0.05).There were no significant difference in HKAA,LDFA,MPTA and PTS between two groups before operation and 1 week after operation(P＞0.05).There was no significant difference in deviation distribution of HKAA at 1 week after op-eration(x2=2.61 1,P=0.456).There were no significant difference in WOMAC and KSS between two groups before operation,3 and 6 months after operation(P＞0.05),and postoperative WOMAC and KSS at 3 and 6 months between two groups were im-proved compared with those before operation(P＜0.05).Conclusion Both RA and RSNA system assisted TKA could obtain ac-curate osteotomy,RA has higher surgical accuracy,RSNA system assisted operation has less trauma,and operation is simpler.

Objective To explore clinical accuracy of remote sensing navigation alignment(RSNA)system in total knee arthroplasty(TKA)and its influence on postoperative clinical efficacy.Methods From May 2021 to May 2022,60 knee os-teoarthritis(KOA)patients with Kellgren-Lawrence(K-L)grade Ⅲ to Ⅳ treated by unilateral primary TKA were selected and divided into RSNA group and traditional operation group according to treatment methods,and 30 patients in each group.There were 6 males and 24 females in RSNA group,aged from 55 to 86 years old with an average of(68.06±8.23)years old;body mass index(BMI)ranged from 22.15 to 34.58 kg·m-2 with an average of(28.20±3.01)kg·m-2;the courses of disease ranged from 2 to 60 months with an average of(18.80±14.80)months;13 patients with grade Ⅲ and 17 patients with grade Ⅳaccording to K-L grading.In traditional operation group,there were 8 males and 22 females,aged from 57 to 85 years old with an average of(67.26±6.32)years old;BMI ranged from 23.94 to 34.55 kg·m-2 with an average of(27.49±2.32)kg·m-2;the courses of disease ranged from 3 to 60 months with an average of(21.30±16.44)months;14 patients with grade Ⅲ and 16 pa-tients with grade Ⅳ according to K-L grading.Western Ontario and McMaster Universities(WOMAC)osteoarthritis index and Knee Society score(KSS)were used to evaluate functional recovery of patients.Hip-knee-ankle angle(HKAA),distal femoral valgus angle(FVA)and distal fermoral flexion angle(DFFA)were measured before operation.HKAA and HKAA deviation angle were measured at 1 week after operation,and defective rate of lower limb force line,femur prosthesis valgus angle(FP-VA)and femoral prosthesis flexion angle(FPFA),respectively,were calculated.Results There were no serious complications such as vascular and nerve injury during operation,and wound healed at stage Ⅰ.Both groups were followed up for 6 months.There were no significant difference in WOMAC index,KSS,HKAA,FVA and DFFA between two groups before operation(P＞0.05).The force line defect rate,HKAA,HKAA deviation angle,FPVA deviation angle and FPFA of RSNA group were 6.7％,(178.74±1.56)°,(1.25±1.56)°,(1.84±0.16)° and(4.85±2.46)°,respectively;while in traditional operation group were 20％,(176.73±3.46)°,(3.27±3.46)°,(2.44±0.26)°,(6.60±1.86)°;the difference between two groups were statistically sig-nificant(P＜0.05).There were no significant difference in WOMAC index and KSS between two groups at 3 and 6 months after operation(P＞0.05).Conclusion RSNA system could reduce defective rate of lower limb force line,FPVA deviation angle and FPFA after TKA,which is more accurate and easy to operate than traditional intramedullary localization surgery while ensuring postoperative efficacy.

Objective To investigate the safety and efficacy of novel bioabsorbable vascular scaffold(BVS)in the treatment of patients with complex coronary artery disease.Methods This was a retrospective,matched,single-center observational study.45 patients with coronary atherosclerotic cardiopathy received BVS treatment in the cardiovascular medicine department Department of the Affiliated Hospital of Guangdong Medical University from June 2020 to June 2021(BVS),and 45 patients treated with drug-eluting stents(DES)group were selected according to matching study requirements during the same period.Baseline,surgical,and follow-up data were compared between the two groups to evaluate safety and efficacy.The main measures of safety were:surgical time,intraoperative adverse events,etc.,and the end point of efficacy was target lesion failure(TLF),including cardiac death,target vessel myocardial infarction,and ischa-driven target lesion revascularization.Results A total of 90 patients were enrolled in this study,all of whom were followed up for at least 3 years.There were 20 cases of bifurcation lesions and 25 cases of diffuse long lesions in the two groups,and 50 cases of imaging were reviewed among the 90 patients.The proportion of stable coronary heart disease,history of diabetes,history of hypertension,history of smoking,pre-dilated balloon pressure and postoperative diastolic blood pressure in BVS group was higher than that in DES group,and the proportion of family history was lower than that in DES group(all P＜0.05).There were no statistically significant differences in the rates of cardiac death,target vessel myocardial infarction,and ischemia-driven revascularization of target lesions between the two groups(all P＞0.05).Binary Logistic regression model analysis showed that the diameter stenosis ratio of target lesions was an independent risk factor for intrastent restenosis(OR 2.786,95％CI 1.096-7.081,P=0.031).Conclusions Compared with traditional DES,BVS implantation has consistent safety and efficacy in the treatment of complex coronary artery disease within 3 years.The diameter stenosis ratio of target lesions was an independent risk factor for intrastent restenosis.

Objective:To compare the efficacy of proximal femoral nail antirotation (PFNA) with metaphyseal expansion or non-expansion in the treatment of femoral intertrochanteric fracture in the elderly.Methods:A retrospective cohort study was conducted to analyze the clinical data of 349 elderly patients with femoral intertrochanteric fracture, comprising 168 males and 181 females, aged 60-84 years [(73.5±8.6)years]. According to AO fracture classification, 108 patients were classified as type A1, 164 type A2, and 77 type A3. Of them, 168 patients received PFNA with metaphyseal expansion (expansion group), while 181 received PFNA with metaphyseal non-expansion (non-expansion group). The operation time, intraoperative blood loss, recessive blood loss, postoperative drainage volume, total blood loss, intraoperative blood transfusion rate and length of hospital stay were compared between the two groups. Visual analogue scale (VAS) scores preoperatively, at 2 and 6 weeks postoperatively of the two groups were detected. The neck-shaft angle and tip-apex distance were measured preoperatively, immediately after surgery, and at 6 months postoperatively. Harris hip score was evaluated at 1, 3, and 6 months postoperatively. Additionally, time to weight-bearing ambulation, fracture healing time, and postoperative complication rate were compared between the two groups.Results:All the patients were followed up for 6-10 months [(7.8±1.2)months]. The operation time for the expansion group was (69.6±12.4)minutes, significantly longer than (65.3±11.5)minutes of the non-expansion group ( P<0.01). Intraoperative blood loss, recessive blood loss, postoperative drainage volume and total blood loss were (124.8±16.9)ml, (684.1±95.3)ml, (123.9±25.1)ml and (932.8±125.4)ml respectively, which were more than those of the non-expansion group [(96.3±12.6)ml, (623.4±87.4)ml, (110.6±29.7)ml, and (830.3±112.6)ml] ( P<0.01). The intraoperative blood transfusion rate was 50.0% (84/168), higher than 38.1% (69/181) of the non-expansion group ( P<0.05). There was no significant difference in the length of hospital stay between the two groups ( P>0.05). There was no significant difference in VAS scores between the two groups before surgery, at 2 and 6 weeks after surgery ( P>0.05). The VAS scores of the two groups at 2 and 6 weeks after surgery were lower than those before surgery, and there were significantly lower scores at 6 weeks after surgery when compared with those at 2 weeks after surgery ( P<0.05). There were no significant differences in neck-shaft angle and tip-apex distance of the two groups before surgery, immediately after surgery and at 6 months after surgery ( P>0.05). In both groups, the neck-shaft angle immediately after surgery and at 6 months after surgery decreased while the apex distance increased when compared with those before surgery ( P<0.05). Furthermore, significantly lower neck-shaft angle and larger apex distance were observed at 6 months after surgery when compared with those immediately after surgery ( P<0.05). There was no significant difference in Harris hip scores at 1, 3 and 6 months after surgery between the two groups ( P>0.05). In both groups, the Harris hip scores at 3 and 6 months after surgery were higher than those at 1 month after surgery ( P<0.05) and the Harris hip scores at 6 months after surgery were higher than that those at 3 months after surgery ( P<0.05). There were no significant differences in time to weight-bearing ambulation, fracture healing time and total postoperative complication rate between the two groups ( P>0.05). Conclusions:For the elderly patients with femoral intertrochanteric fractures, PFNA with proximal metaphyseal expansion or non-expansion is equally effective in shortening hospital stay, relieving pain, improving reduction quality, promoting hip function recovery and reducing complication rate. However, PFNA with non-expansion treatment can shorten the operation time, reduce intraoperative blood loss, recessive blood loss, postoperative drainage volume and total blood loss, and lower intraoperative blood transfusion rate.

The incidence of male infertility has been increasing year by year,and one of the major causes is testicular spermato-genic epithelial injury,which affects the spermatogenic function of the testis.Ferroptosis is a novel mode of cell death and plays an im-portant role in testicular cell injury.Some traditional Chinese medicines can intervene in the progression of testicular injury by regula-ting the ferroptosis pathway in testicular spermatogenic epithelia.This paper focuses on the effect of traditional Chinese drugs in regula-ting the ferroptosis pathway in testicular cells,and summarizes the advances in the studies of traditional Chinese medicines in the treat-ment of testicular spermatogenic epithelial injury,aiming to provide a theoretical basis for the selection of relevant medicines and their clinical application.