AIM: To observe the changes of retinal nerve fiber layer(RNFL)thickness and radial peripheral capillary(RPC)density in patients with unilateral branch retinal vein occlusion(BRVO), and further analyze the correlation between RPC density and RNFL thickness.METHODS: Observational study. Totally 37 patients with unilateral BRVO diagnosed at the ophthalmology department of First Hospital of Qinhuangdao from October 2020 to January 2022 were selected, the 37 affected eyes were the unilateral BRVO group, and 37 fellow healthy eyes were the contralateral unaffected group, and 35 healthy individuals(35 right eyes were selected)without ocular diseases during the same period were selected as the normal control group. The best corrected visual acuity, intraocular pressure, anterior segment, fundus and optical coherence tomography angiography(OCTA)were examined in both eyes of all BRVO patients and healthy individuals. The central macular thickness(CMT), the RNFL thickness, and the optic disc-AV crossing distance(DAVD)were measured by built-in software of the OCTA equipment. The optimized U-net algorithm was used to eliminate the large blood vessels, and then the RPC density was calculated. The CMT, RNFL thickness and RPC density were compared among the three groups. And the correlations of the RPC density with the CMT, RNFL thickness, and the DAVD were investigated.RESULTS: Compared with the contralateral unaffected group and the normal control group, the CMT and the RNFL thickness were significantly thickened in the unilateral BRVO group(all P<0.05); there were no statistical differences in the CMT and the RNFL thickness between the contralateral unaffected group and the normal control group(all P>0.05). The RPC density in the unilateral BRVO group increased compared with the contralateral unaffected group and decreased compared with the normal control group, but there was no statistically difference(all P>0.05). However, the RPC density in the contralateral unaffected group decreased compared with the normal control group(P<0.05). The RPC density in the unilateral BRVO group was not correlated with the CMT(P=0.960), but positively correlated with the RNFL thickness(r=0.401, P=0.014)and negatively correlated with the DAVD(r=-0.339, P=0.040).CONCLUSION: The RNFL thickened significantly and the RPC density did not change significantly in the optic disc area of BRVO patients. The RPC density is positively correlated with the RNFL thickness, indicating that the RNFL thickness can be used as a monitoring indicator to analyze and study the damage degree of the RPC density.

L-theanine is an important natural non-protein amino acid that is widely used in food and medicine. Although in previous studies, a microbial fermentation method for L-theanine without the addition of ethylamine has been developed, the conversion rate of this process needs to be further improved. In this study, we constructed a de novo synthesis pathway of L-theanine with glucose as the substrate. First, an in vitro transformation pathway containing ω-transaminase (TA) and γ-glutamylmethylamide synthetase (GMAS) was designed, optimized, and introduced into the chassis strain Escherichia coli K12 W3110 to achieve de novo synthesis of L-theanine. To improve the synthesis efficiency through metabolic engineering, we increased the copies of the GMAS gene gams and the TA gene spuC and enhanced the expression of the aldehyde dehydrogenase gene eutE to provide sufficient acetaldehyde substrate, knocked out the lactate dehydrogenase gene ldhA and the pyruvate formate lyase gene pflB to block bypass metabolism, and introduced the alanine dehydrogenase gene alD to recycle alanine. Furthermore, we over-expressed the phosphoenolpyruvate carboxylase gene ppc to enhance the carbon flux of the TCA cycle, knocked out the succinyl-CoA synthase gene sucCD to reduce the loss of downstream flux of TCA, and integrated the glutamate dehydrogenase gene gdh to enhance the supply of L-glutamate. Finally, the polyphosphate kinase gene ppk was introduced to the ATP cycle, which enhanced the energy supply in L-theanine production. The recombinant strain Tea11 produced 22.60 g/L L-theanine in a 5 L fermenter in 28 h, with a conversion rate of 41.71%. This synthetic pathway in this study balanced the relationship between the supply of ethylamine and the production of theanine, providing a new idea for metabolic engineering of microorganisms to produce L-theanine.
Glutamates/biosynthesis* ; Metabolic Engineering/methods* ; Escherichia coli/genetics* ; Fermentation ; Transaminases/metabolism* ; Amide Synthases/metabolism* ; Glucose/metabolism*

L-tyrosine is one of the 20 amino acids that make up proteins and is an essential amino acid for mammals, often used as a nutritional supplement. The conventional methods for synthesizing L-tyrosine have some problems such as the production of many by-products, high requirements for production conditions, and environmental pollution. In this study, we designed and constructed a multi-enzyme cascade for the synthesis of L-tyrosine with alanine, glutamate, ammonium chloride, and phenol as substrates. Initially, the sources of glutamate oxidase, alanine aminotransferase, and tyrosine phenol lyase were screened and analyzed, which was followed by the identification of the rate-limiting enzyme in the reaction process. A colorimetric screening method was established, and the rate-limiting enzyme DbAlaA was engineered to enhance its activity by 40.0%. Subsequently, the reaction conditions, including temperature, pH, cell concentration, and surfactant and coenzyme dosages, were optimized. After optimization, the yield of L-tyrosine reached 9.93 g/L, with a alanine conversion rate of 54.90%. Finally, a feed-batch fermentation strategy was adopted, and the yield of L-tyrosine reached 56.07 g/L after 24 h, with a alanine conversion rate of 65.22%. This study provides a reference for the whole-cell catalytic synthesis of L-tyrosine and its industrialization.
Tyrosine/biosynthesis* ; Escherichia coli/metabolism* ; Tyrosine Phenol-Lyase/genetics* ; Multienzyme Complexes/metabolism* ; Fermentation

Objective To investigate the prediction of diffusion kurtosis imaging(DKI)and intra voxel incoherent motion(IVIM)imaging global histogram parameters for the efficacy of neoadjuvant chemotherapy(NAC)in patients diagnosed with breast invasive ductal carcinoma.Methods A total of 69 patients with breast invasive ductal carcinoma confirmed by penetration pathology were retrospectively selected.Prior to undergoing NAC,all patients underwent sequential scans including MR conventional(T1WI,T2WI),dynamic contrast enhancement(DCE),DKI,and IVIM.After surgery,the patients were divided into significant group(40 patients)and non-significant group(29 patients)based on the efficacy of NAC,which was evaluated using the Miller-Payne(MP)grading method criteria.The differences in global histogram parameters of DKI[mean diffusivity(MD),mean kurtosis(MK)]and IVIM(D value,f value,D*value)between the significant group and the non-significant group were compared by the two-independent sample t-test and Mann-Whitney U test.In addition,the receiver operating characteristic(ROC)curve was plotted,and Spearman rank correlation analysis was used to evaluate the diagnostic efficacy and correlation of DKI and IVIM global histogram parameters in predicting NAC efficacy.The DeLong test was used to compare whether there was statistical significance in area under the curve(AUC)differences among histogram parameters.Results The DKI MD value(90th percentile,mean,median,maximum,range,root mean square),IVIM D value(mean,range,root mean square,median)and D*value(entropy,90th percentile)of patients with breast invasive ductal carcinoma in the significant group with efficacy of NAC were higher than those in the non-significant group,while the DKI MK value(mean and median)were lower than those in the non-significant group,and all the differences mentioned above were statistically significant(P＜0.05).The AUC,sensitivity and specificity of DKI combined with IVIM global histogram parameters were the highest,which were 0.816,72.41％and 90.00％,respectively.MD value,D value and D*value were negatively correlated with the efficacy of NAC in breast invasive ductal carcinoma.MK value was positively correlated with NAC efficacy significance.Conclusion DKI combined with IVIM global histogram parameters can effectively predict the efficacy of NAC in patients with breast invasive ductal carcinoma and provide effective value for clinical NAC preoperative efficacy evaluation.

Objective To investigate the relationship between systemic immune-inflammation index (SII)and lower extremity vascular disease in patients with type 2 diabetes mellitus (T2DM).Methods A cross-sectional study was conducted on 390 T2DM patients admitted in our department from January 2013 to January 2024.According to the diagnostic criteria for lower extremity vascular disease in T2DM patients,they were divided into a lower extremity vascular disease group (n=158)and a control group (n=232).General data and results of laboratory tests were compared between the 2 groups.Spearman correlation analysis was used to identify the related factors for lower extremity vascular diseases in T2DM patients.The correlation between SII and lower extremity vascular diseases in T2DM patients was analyzed using the Row Mean Scores and Cochran-Armitage Trend analysis.Multivariate logistic regression analysis was applied to identify the risk factors for lower limb vascular lesions in T2DM patients.Receiver operating characteristic (ROC)curve was plotted to evaluate the diagnostic efficacy of SII for lower extremity vascular disease in the patients.Results Compared with T2DMpatients without lower extremity vascular disease,those with lower extremity vascular disease were older,had higher levels of total cholesterol (TC),low-density lipoprotein cholesterol (LDL-C),SII,larger proportion of carotid vascular lesions,and increased proportion of no-taking statins.The lower extremity vascular disease in T2DM patients was positively correlated with SII/100 (r=0.429,P<0.001),age (r=0.517,P<0.001),TC (r=0.161,P=0.001),LDL-C (r=0.117,P=0.021),carotid artery lesions (r=0.101,P=0.047),no-taking statins (r=0.266,P<0.001).Logistic regression analysis showed that SII,age,LDL-C,and no-taking statins were the risk factors for lower extremity vascular lesions in T2DM patients (P<0.01).The area under the curve (AUC)value of SII combined with age,LDL-C,and no-taking statins in predicting lower extremity vascular disease in T2DM patients was 0.896.Conclusion SII is not only a risk factor,but also a simple marker for lower extremity vascular disease in T2DM patients,suggesting that inflammatory response plays an important role in the occurrence and development of lower extremity vascular disease in T2DM.

BACKGROUND:In recent years,computer-assisted navigation has gradually attracted attention in the medical field.Some scholars have reported that the clinical effects of computer navigation in total knee arthroplasty vary.To explore the clinical effect of the new generation of Brainlab Knee 3 navigation system,this study is conducted. OBJECTIVE:To analyze the application effect of computer navigation system(Brainlab Knee 3)combined with gap balance technology in total knee arthroplasty. METHODS:A total of 71 patients received total knee arthroplasty at the Department of Joint Surgery of Dalian Second People's Hospital from November 2020 to May 2021.In the navigation group,35 patients underwent total knee arthroplasty by computer navigation combined with gap balance.In the traditional group,36 patients underwent osteotomy with traditional surgical instruments.The difference between medial and lateral joint spaces,knee range of motion,hospital for special surgery knee score,hip-knee-ankle angle,deviation values of coronal femoral component angle,coronal tibial component angle,and sagittal tibial component angle were compared between the two groups. RESULTS AND CONCLUSION:(1)In the navigation group,the differences of intraoperative medial and lateral joint gap at knee extension 0,1,and 2 mm were found in 19,14,and 2 cases,respectively.The gap difference was 0 mm in 18 cases,1 mm in 15 cases and 2 mm in 2 cases at 90° degree knee flexion.In the traditional group,the gap difference at knee extention was 0 mm in 10 cases,1 mm in 20 cases,and 2 mm in 6 cases.The gap difference at 90 degree knee flexion was 0 mm in 10 cases,1 mm in 15 cases and 2 mm in 8 cases.(2)The operation time in the navigation group was longer than that in the traditional group(P<0.05),and two patients in the navigation group developed lower limb intermuscular vein thrombosis after surgery,and none of the patients in the traditional group had complications.(3)The range of motion between the two groups increased significantly at 6 and 12 months after surgery,and the range of motion in the navigation group was higher than that in the traditional group(P<0.05).(4)At 12 months after surgery,the hospital for special surgery knee scores of both groups increased significantly,and the hospital for special surgery knee score in the navigation group was higher than that in the traditional group(P<0.05).(5)At 6 months after surgery,the deviation values of hip-knee-ankle angle,coronal femoral component angle,coronal tibial component angle,and sagittal tibial component angle of navigation group were significantly lower than those in the traditional group(P<0.05).(6)The results showed that computer navigation technique combined with gap balance in total knee arthroplasty had advantages in postoperative range of motion,lower limb alignment and the accuracy of tibial prosthesis component position,and joint function recovered well.

Objective To explore the research dynamics and hotspots of project management in the field of hospital man-agement,and analyze the contents that still need to be improved,so as to provide references for the subsequent research,and provide hospital managers with practical experience in hospital management.Methods Based on the PubMed database,we used the citexs data analysis platform to analyze the literature and big data from January 2012 to December 2022 on the application of project management in the field of hospital management.Results The effective literature was retrieved from 4236 articles,and the analysis found thatthe annualnumberofpublicationsinthisfield hasbeenincreasing,2021 sawthe highestannualnumberof 573 articles,and the fastest growth rate was 20.36% in 2017.The country with the most publications is the United States(1 546 articles,36.5% ),the research institution with the most publications is Monash University,Australia,the journal with the most publications is BMJ Open(124 articles),and the key words with the highest frequency of occurrence in the retrieved literature are quality improvement,primary care improvement,covid-19,telemedicine.Conclusion The research in this field has been rapidly developed and is in a fast rising phase.In almost every organization and industry,the share of project management or"projectization"is increasing,and project management has become an important part of hospital management research and prac-tice.In the context of building a modern hospital management system,the application of project management to hospital manage-ment is an effective means of improving the level of fine hospital management.

Objective To sort out and summarize the research hotspots and trends of Chinese medicine nursing technolo-gy at the present stage.Methods We searched the research literature on TCM nursing technology included in China Knowledge,Wanfang,and Wipu build-up to November 30,2023,and used CiteSpace 6.1.R6 software to perform co-occurrence analysis of research institutions and keyword clustering,timeline,and emergence analysis.Results A total of 5 771 documents were in-cluded,with a general upward trend in the number of publications,peaking at 692 publications in 2021.5 206 documents from 673 journals were included in the research literature,of which 19 journals had ≥50 publications(35.47％).2 087 research or-ganizations were involved,of which 27 had ≥20 publications(13.24％).Involving 9 484 authors,there were a total of 8 au-thors ≥5 in the cluster,indicating the existence of stable teamwork in the cluster.The keyword co-occurrence analysis yielded the research hotspots of TCM nursing technology as TCM nursing,training,nursing management,clinical efficacy,complica-tions,and quality of life.Conclusion Based on the econometrics and visualization analysis of the literature on TCM nursing technology,we explored the research hotspots and trends in this field,and provided two theoretical paths for medical institution managers to construct and optimize the management system of TCM nursing technology:to standardize the TCM nursing technology in hospitals and establish a clinical access management system;and based on the multidimensional management method,to inno-vate the training system of TCM nursing technology.

Objective To explore the association of the magnitude of systolic blood pressure reduction(SBPr)with post-procedure 24 h symptomatic intracranial hemorrhage(sICH)and 90-day clinical outcomes in patients with successful endovascular thrombectomy(EVT).Methods Consecutively registered patients with EVT caused by anterior circulation large vessel occlusion stroke(LVOS)in the First Affiliated Hospital of Wannan Medical College(Yijishan Hospital)between July 2015 and April 2023 and patients with successful reperfusion were analyzed.Demographic data,medical history(hypertension,diabetes),the trial of Org 10172 in acute stroke treatment(TOAST)classification,the baseline National Institutes of Health Stroke Scale(NIHSS)score and the baseline Alberta stroke early CT(ASPECT)score of patients were collected.And procedure related parameters(including time from onset to puncture,time from onset to reperfusion,occluded site[internal carotid artery,M1 segment of middle cerebral artery,M2 segment of middle cerebral artery],collateral circulation status[determined based on preoperative occluded angiography showing the range of collateral circulation in the occluded vessel area,defined as good collateral circulation with a reflux range of ≥ 50％and poor collateral circulation with a reflux range of＜50％]),immediate postoperative reperfusion status(evaluated using the modified thrombolysis for cerebral infarction[mTICI]grading,successful reperfusion defined as mTICI grading of 2b-3),24 hours sICH,and 90 days clinical outcomes(evaluated using the modified Rankin scale score at 90days after EVT,with a score ≤ 2indicating a good prognosis and a score＞2indicating a poor prognosis).SBPr was defined as(baseline SBP-mean SBP)/baseline SBP x 100％.According to the the magnitude of SBPr,SBPr is divided into 5 categories(＜-10％,-10％-10％,＞10％-20％,＞20％-30％and＞30％).Based on the clinical outcomes at 90 days and the occurrence of sICH at 24 hours after EVT,patients were divided into a good prognosis group and a poor prognosis group,as well as an sICH group and a non-sICH group.The relationship between SBPr and postoperative 90 days clinical prognosis or sICH was analyzed using a binary Logistic regression model.Subgroup analysis was conducted based on a history of hypertension(yes and no),continuous intravenous hypotensive therapy(yes and no),baseline ASPECT scores(3-5 and 6-10),and collateral circulation status(good and bad).Using a restricted cubic plot to depict the relationship between SBPr and sICH and clinical prognosis at 90days.Results(1)In total,731 patients were included.The median age was 71(62,77)years and 424(58.0％)were men.The median baseline NIHSS score was 14(12,18),the median baseline ASPECT was 9(7,10),405(55.4％)patients achieved 90-day modified Rankin scale score 0-2,and 35 patients(4.8％)developed sICH.(2)Multivariate analysis showed that the older age(OR,1.036,95％CI 1.017-1.056),the higher baseline NIHSS score(OR,1.095,95％CI1.049-1.144),the lower baseline ASPECT score(OR,0.704,95％CI 0.636-0.780),diabetes(OR,1.729,95％CI 1.084-2.758),bad collateral circulation(good collateral circulation vs.bad collateral circulation,OR,0.481,95％CI 0.332-0.696)and SBPr＞30％(SBPr-10％-10％as a reference,OR,2.238,95％CI 1.230-4.071),the higher the risk of poor clinical outcomes at 90 days(all P＜0.05).Continuous intravenous hypotensive therapy is a risk factor for postoperative 24 h sICH(OR,2.278,95％CI 1.047-4.953;P=0.038),while SBPr 20％-30％is associated with a lower risk of postoperative 24 h sICH(SBPr-10％-10％as a reference,OR,0.362,95％CI0.131-0.998;P=0.049).(3)The restrictive cube plot shows that there is a U-shaped relationship between SBPr after EVT and poor clinical outcomes at 90 days,while there is a nearly linear relationship with the occurrence of sICH.The more SBP reduction,the lower the incidence of sICH.(4)In the subgroup analyses,in the non-hypertension history and the good collateral circulation group,SBPr＞30％has a higher risk of poor clinical outcomes compared to SBPr-10％-10％(OR and 95％CI were 2.921[1.000-8.528]and 2.363[1.078-5.183],respectively,with P=0.05 or P＜0.05);After EVT,the group receiving continuous intravenous hypotensive therapy and the baseline ASPECT score 6-10 groups showed a significant correlation between SBPr＞30％and poor clinical outcomes at 90 days(SBPr-10％-10％as a reference,OR and 95％CI were 2.646[1.168-5.993]and 2.481[1.360-4.527],respectively,with P＜0.05).The correlation between SBPr and lower incidence of sICH was only found in the subgroup of poor collateral circulation(SBPr-10％-10％as a reference,SBPr＞20％-30％:OR,0.133,95％CI 0.027-0.652;SBPr＞30％:OR,0.104,95％CI 0.013-0.864;all P＜0.05).Conclusions Among patients who achieved successful reperfusion with EVT,SBPr might be related to a worse functional outcome at 90 days and sICH 24 h after operation.However,the relationship may exhibit significant heterogeneity across different subgroups.Baseline ASPECT score,history of hypertension,collateral circulation,and the use of continuous venous hypertension after EVT have been highlighted in individualized blood pressure management after EVT.

AIM: To quantify early changes of macular capillary parameters in type 2 diabetic patients using optical coherence tomography angiography(OCTA).METHODS: Retrospective case study. A total of 49 healthy subjects, 52 diabetic patients without retinopathy(noDR)patients, and 43 mild nonproliferative diabetic retinopathy(mNPDR)patients were recruited. Capillary perfusion density, vessel length density(VLD), and average vessel diameter(AVD)were calculated from macular OCTA images(3 mm×3 mm)of the superficial capillary plexus after segmenting large vessels and the deep capillary plexus. Parameters were compared among control subjects, noDR, and mNPDR patients. The area under the receiver operating characteristic curve estimated the abilities of these parameters to detect early changes of retinal microvascular networks.RESULTS: Significant differences were found in the VLD and AVD among the three groups(P<0.001). Compared with the control group, the noDR group had significantly higher AVD(P<0.05). VLD of both layers in patients of mNPDR group was significant decreased compared with that of noDR group(all P<0.01). Deep AVD had a higher area under the curve(AUC)of 0.796 than other parameters to discriminate the noDR group from the healthy group. Deep AVD had the highest AUC of 0.920, followed by that of the deep VLD(AUC=0.899)to discriminate the mNPDR group from the healthy group.CONCLUSIONS: NoDR patients had wider AVD than healthy individuals and longer VLD than mNPDR patients in both layers. When compared with healthy individuals, deep AVD had a stronger ability than other parameters to detect early retinal capillary impairments in noDR patients.