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

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.

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.

Objective To investigate the influencing factors for acute multiple vessels occlusion(MVO)and its impact on the prognosis of patients with anterior circulation acute large vessel occlusion stroke(ALVOS)who achieved successful recanalization after endovascular treatment(EVT).Methods Patients with anterior circulation ALVOS who received successful EVT at the Yijishan Hospital of Wannan Medical College between July 2015 and April 2023 were retrospectively analyzed.Baseline data,including age,sex,onset-to-puncture time(OTP),onset-to-recanalization time(OTR),medical history(including atrial fibrillation,diabetes,hypertension),alcohol and smoking history,admission blood pressure(systolic and diastolic),Alberta stroke program early CT score(ASPECTS),National Institutes of Health stroke scale(NIHSS)score,trial of Org 10172 in acute stroke treatment(TOAST)classification(atherosclerotic type,cardioembolic type,and other etiology types),and 90-day modified Rankin scale(mRS)score were collected.Collateral circulation was assessed based on the degree of contrast agent reflux observed in the occluded arterial supply area during delayed DSA,and patients were classified into poor and good collateral circulation groups.Malignant cerebral edema was defined as a midline shift of ≥5 mm on the follow-up CT scan performed on day 3 post-surgery.The primary endpoint(efficacy indicator)was the 90-day mRS score,with mRS score≤ 2 considered as a good prognosis and mRS score＞2 considered as a poor prognosis.The secondary endpoint(safety indicator)was the 90-day mortality rate.All patients were divided into MVO and non-MVO groups based on whether they had single or multiple intracranial vessel occlusions.Acute MVO was defined as the detection of acute occlusion of other large or medium vessels,in addition to the main vessels(internal carotid artery or M1/M2 segments of the middle crebral artery[MCA]),in CT angiography,MR angiography,or DSA,resulting in ischemia in brain regions distinct from the main occlusion area.Factors that showed statistically significant differences in univariate analysis were further analyzed using multivariate Logistic regression to identify the risk factors for the occurrence of acute MVO and the factors associated with the prognosis of ALVOS patients.Results A total of 846 patients with ALVOS were included,with ages ranging from 26 to 94 years(mean age[69±11]years).The proportion of male patients was 57.2％(484/846).The median admission ASPECTS was 8(7,9)and the median admission NIHSS score was 14(12,18).The incidence of malignant cerebral edema at 3 days post-surgery was 13.4％(112/835),and the 90-day mortality rate was 19.1％(162/846).(1)Among the 846 ALVOS patients,810(95.7％)were in the non-MVO group and 36(4.3％)were in the MVO group.Univariate analysis showed significant differences between the MVO and non-MVO groups in terms of atrial fibrillation,malignant cerebral edema,admission ASPECTS,admission NIHSS scores,TOAST classification,collateral circulation,rate of complete recanalization,and 90-day poor prognosis rate(all P＜0.05).However,there was no statistically significant difference in 90-day mortality between the two groups(P=0.193).Multivariate Logistic regression analysis showed that TOAST classification of cardioembolic type(OR,16.089,95％CI 1.835-141.061,P=0.012)and other etiology types(OR,9.768,95％CI 1.078-88.540,P=0.043)were associated with the occurrence of MVO.(2)Among the 846 ALVOS patients,445 had a good prognosis at 90days,and 401 had a poor prognosis.Univariate analysis showed that,compared to the good prognosis group,the poor prognosis group had a lower proportion of males and smokers,and a higher proportion of patients with older age,higher baseline systolic blood pressure,hypertension,diabetes,and atrial fibrillation(all P＜0.01).Additionally,the poor prognosis group had higher admission NIHSS scores(P＜0.01),lower admission ASPECTS,lower rates of good collateral circulation and complete recanalization,higher rates of malignant cerebral edema and MVO,and statistically significant differences in TOAST classification distribution(all P＜0.01).Multivariate Logistic regression analysis showed that MVO was associated with poor 90-day prognosis in ALVOS patients after EVT(OR,3.368,95％CI 1.149-9.878,P=0.027).Furthermore,older age(OR,1.045,95％CI 1.025-1.066),diabetes(OR,1.719,95％CI 1.080-2.734),higher baseline systolic blood pressure(OR,1.012,95％CI 1.004-1.019),lower admission ASPECTS(OR,0.746,95％CI 0.674-0.826),higher admission NIHSS score(OR,1.115,95％CI 1.070-1.162),without immediate postoperative complete recanalization(OR,0.413,95％CI 0.290-0.592),poor collateral circulation(OR,0.594,95％CI 0.415-0.851),and malignant cerebral edema(OR,6.191,95％CI 3.026-12.670)were all associated with poor 90-day prognosis after EVT in ALVOS patients(all P＜0.05).Conclusions The TOAST classification of cardioembolic type and other etiology types is associated with MVO.MVO is a risk factor for poor outcomes after successful EVT in ALVOS patients.

Objective To observe splenic T cell apoptosis and XIAP-associated factor 1(XAF1),FAS,and tumor necrosis factor(TNF)-α protein expression levels in rats with acute lung injury(ALI),and to determine their roles in the protective effect of Yifei Jianpi formula.Methods Sixty male specific pathogen-free SD rats were divided randomly into blank,model,positive control,and high-,medium-,and low-dose Yifei Jianpi formula groups.Rats in the positive control group were given 0.5 g/kg dexamethasone by gavage,and rats in the high-,medium-,and low-dose Yifei Jianpi formula groups were given 12,6,and 3 g/kg Yifei Jianpi formula by gavage,respectively.Rats in the model and blank groups were given equal amounts of saline by gavage.All medications were administered once a day for 14 days.Lung function testing was carried out in all rats.We observed the imaging characteristics of the lungs and changes in the organ index and lung tissue wet/dry weight(W/D)in each group,and detected the pathological changes in lung tissues by hematoxylin-eosin staining.Splenic T-cell subpopulations(CD4+/CD8+)and apoptosis of splenic T-cells were detected by flow cytometry and XAF1,FAS,and TNF-α protein expression levels in the spleen were detected by Western Blot.Results Rats in the model group showed reduced lung function,decreased spleen and thymus organ indexes,and significantly higher W/D of lung tissue(P＜0.01).In addition,they had inflammatory exudation and alveolar rupture in the lung tissue,accompanied by thickening of the lung texture and large areas of ground-glass shadows,with a significant decrease in T-cell subsets(CD4+/CD8+)and significant increases in XAF1,FAS,and TNF-α proteins,and in the rate of T-cell apoptosis(P＜0.01).Yifei Jianpi formula significantly reduced the W/D spleen of rat lung tissues,significantly increased the thymus organ index(P＜0.05,P＜0.01)and the T-cell subpopulation(CD4+/CD8+),and significantly decreased the protein expression levels of XAF1,FAS,and TNF-α,and the T-cell apoptosis rate(P＜0.05,P＜0.01).Conclusions ALI induced up-regulation of XAF1,FAS,and TNF-α protein expression and T-cell apoptosis in the spleen of rats,and Yifei Jianpi formula may protect against ALI by down-regulating these factors.

Existing studies have shown that Astragalus membranaceus(AM)and its active ingredients astragalus polysaccharides,oninon,and astragalus methyl glycosides can attenuate X-ray radiation-induced injury.However,there are no studies on how isoliquiritigenin(ISL)attenuate the bystander effect of bone marrow mesenchymal stem cells(BMSCs)induced by carbon ion radiation therapy for lung cancer.This study aimed to investigate the AM-derived small molecule ISL to enhance radiotherapy sensitivity by attenuating the carbon ion radiation-induced bystander effect(RIBE)in BMSCs to elucidate its mecha-nism of action.In this study,we established a C57BL/6 mouse lung cancer transplantation tumor model in vivo and a co-culture model of A549 cells and BMSCs in vitro,and the models were successfully treated with carbon ions.In further work,we used flow cytometry,immunofluorescence,Western blot,enzyme-linked immunosorbent assay(ELISA),inhibitor,short hairpin RNA(shRNA),Cell Counting Kit-8(CCK-8),and other methods to illustrate the mechanism.In the next experiments,we found that ISL combined with carbon ion radiotherapy had a significant anti-tumor effect and protected BMSCs from radiation damage.The aim of this study was to investigate the potential of ISL in enhancing the sensitivity of lung cancer cells to radiotherapy and attenuating RIBE in both in vitro and in vivo settings.Traditional Chinese medicine combined with radiation therapy is a promising and innovative treatment for non-small cell lung cancer.These results establish a theoretical foundation for further clinical development of ISL as a potential radiosensitizer option.

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.

ObjectiveTo explore the interaction among root fungi of Stellaria dichotoma var. lanceolata， soil factors， and main components of medicinal materials in lithosol habitats. MethodHigh-throughput sequencing technology was employed to determine the fungal community of the root system of S. dichotoma var. lanceolata at different levels （bulk soil， rhizosphere soil， rhizoplane soil， and root interior） and the soil properties of the root system （bulk and rhizosphere）， and the relationship among the fungal community， soil properties， and the main components of medicinal materials was analyzed. ResultThe total phosphorus， available phosphorus， alkaline nitrogen， dissolved organic carbon， and soil water content in the rhizosphere soil of S. dichotoma var. lanceolata were slightly higher than those in the rhizosphere， but the difference was not significant. Ascomycota is the dominant phylum of root fungi in S. dichotoma var. lanceolata. In the progressive level of bulk-rhizosphere-rhizoplane-root interior system， although the fungal diversity gradually decreased， the abundance of Hypocreales， a new phylum （unclassified_ k_ Fungi）， Helotiales， and Natipusilales gradually increased， among which Hypocreales is the most important fungal group in the root system of S. dichotoma var. lanceolata. The structural equation model （SEM） shows that the physicochemical factors of the root-soil play an important regulatory role in the fungal community and the main components of medicinal herbs， with soil total nitrogen， alkaline nitrogen， soil water content， and pH being the main regulatory factors. Soil nitrogen content is the key to promoting the main components of the medicinal herbs， and Penicillium fungi are the key fungal group to regulate the main components of the medicinal herbs. ConclusionIt highlights that the physicochemical properties of the soil of S. dichotoma var. lanceolata play a crucial role in the fungal community and the components of medicinal materials. Hypocreales fungi in the root of S. dichotoma var. lanceolata were an important group， and Penicillium fungi had a certain role in mediating the components of medicinal materials.