Objective To evaluate the possibility of detection mutations of multiple genes in stool for secondary screening for colorectal cancer.Methods Tumor specimens and stool samples from 40 patients with colorectal cancer and 40 normal persons were examined for mutations of p53,K-ras and APC gene by polymerase chain reaction single strand conformation polymorphism(PCR-SSCP) and silver nitrate staining.Results ①The mutation rate of p53,K-ras and APC gene in the tissues and stools of colorectal cancer respectively were 57.50%,50.00%,60.00% and 42.86%,40.00%,51.43%,and no mutations were found in normal mucosa and stool.②The mutation ratioes between multiple gene and single gene had significant difference(P

Objective To study the function of vascular endothelial growth factor (VEGF) in type 2 diabetes model rats and its effect on focal cerebral ischemia induced by middle cerebral artery occlusion in these rats. Methods Focal cerebral ischemia was induced by middle cerebral artery occlusion for 6 hours in type 2 diabetes rats and normal control rats.Blood vessels morphology was examined by ink perfusion,infarct size was measured by TTC and expression of VEGF and CD34 were evaluated by immunohistochemistry staining. Results Ink perfusion revealed increased number of small vessels in type 2 diabetes rats. Infarct size was significantly smaller in type 2 diabetes rats ( ( 80. 07 ± 11.21 ) mm3 ) than that in normal controls ((98. 91 ± 14. 86) mm3,t = 2.48,P = 0. 0326). There were more hemorrhage lesions in the ischemic hemisphere in type 2 diabetes rats when comparing with the controls. VEGF and CD34 showed significantly higher expression in type 2 diabetes rats than in normal controls. Conclusions High expression of VEGF and CD34 are found in type 2 diabetes rats after middle cerebral artery occlusion. There is cerebrolvascular remodeling in diabetes rats. While this diabetes-induced remodeling appears to prevent infarct expansion,the changes also increase the risk of hemorrhagic transformation. The latter may result in poor prognosis.

OBJECTIVE:To establish the method for the determination of mildronate in human plasma and urine,and to study the pharmacokinetic characteristics in healthy volunteers. METHODS:After precipitating plasma and urine sample,LC-MS/MS method was adopted. Dikma Diamonsil C18 column was used with mobile phase consisted of methanol-water(containing 0.2% for-mic acid,0.3% ammonium acetate)(31∶69,V/V)at the flow rate of 0.6 ml/min. ESI was adopted in MRM mode,by using nega-tive ion. The ion for quantitative analysis were m/z 147.10→58.20 (mildronate) and m/z 152.00→110.10 (internal standard,acet-aminophen). The pharmacokinetic parameters of mildronate with single administration and multiple administration were calculated by using DAS 2.1 software and compared. RESULTS:The linear range of mildronate in plasma were 0.02-20 ng/ml(r=0.999 3) and in urine were 0.05-40 ng/ml(r=0.998 2). The lowest limits of quantitation were 0.02 and 0.05 ng/ml. Precision and recovery met the requirements of biological specimen determination,and endogenous impurities hadn’t effect on the determination. The main pharmacokinetics parameters of low-dose,medium-dose and low-dose(250,500,750 mg)of mildronate in plasma with single ad-ministration were as follows:t1/2 were(3.39±0.81),(5.52±0.57)and(5.32±0.96)h;tmax were(0.80±0.45),(1.38±0.43)and (1.10±0.36)h;cmax were(4.17±1.46),(8.08±1.04)and(15.04±1.86)ng/ml;AUC0-36 h were(24.55±5.81),(45.50±7.07)and (85.60 ± 13.09)ng·h/ml. In the dose range,cmax,AUC0-36 h h had a linear relationship with dose (R2 were 0.974 5 and 0.968 3). The main pharmacokinetic parameters of low-dose of mildronate with multiple administration after keeping stable were as follows:cmin was(0.28 ± 0.10)ng/ml;AUCs was(38.78 ± 4.18)ng·h/ml;cs was(1.62 ± 0.17)ng/ml;DF was(3.81 ± 1.14);t1/2 was(6.17 ± 1.46)h;tmax was(1.20 ± 0.33)h;cmax was(6.46 ± 1.96)ng/ml;AUC0-36 h was(40.33 ± 4.65)ng·h/ml;accumulation factor of cmax and AUC were(1.73±0.90)and(1.64±0.40). Compared with single administration,t1/2,cmax and AUC of mildronate with multiple admin-istration after keeping stable all changed,and tmax had no signifi-cant difference. After single administration,26 h accumulative excretion rate of those groups were (0.004 009 ± 0.001 1)%, (0.004 026±0.001 01)% and(0.003 858±0.000 68)% respec-tively. CONCLUSIONS:Established method is sensitive,accurate and specific,and suitable for the determination of mildronate concentration in human plasma and urine and pharmacokinetics study. Mildronate capsule shows certain accumulation effect in healthy volunteers,and linear pharmacokinetic characteristics.

Objective:To explore the value of tumor stroma ratio (TSR) in non-small lung cancer (NSCLC) tissue in predicting the efficacy of tumor immunotherapy.Methods:The clinical and histopathological data of patients with stage ⅢB-Ⅳ NSCLC treated with immune checkpoint inhibitors in the Renmin Hospital of Wuhan University from January 2017 to December 2020 were collected. Taking 50% as the TSR boundary value, the patients were divided into low TSR group (≤50%) and high TSR group (>50%) . The histopathological features, 4-cycle objective response rate (ORR) and disease control rate (DCR) , 6-cycle ORR and DCR, and progression-free survival (PFS) were compared between the two groups. Univariate and multivariate Cox regression models were used to analyze the prognostic factors related to PFS.Results:A total of 50 patients were included, including 27 with low TSR and 23 with high TSR. There were no significant differences between the two groups in age ( χ2=0.59, P=0.441) , gender ( P=0.578) , smoking history ( χ2=0.12, P=0.730) , histopathological type ( χ2=2.33, P=0.313) , TNM stage ( χ2=0.22, P=0.636) , 4-cycle ORR ( χ2=0.48, P=0.487) and DCR ( P=0.593) , 6-cycle ORR ( χ2=0.05, P=0.818) and DCR ( P=0.641) . The incidence of brain metastasis was higher in the high TSR group than that in the low TSR group [34.8% (8/23) vs. 7.4% (2/27) , χ2=4.23, P=0.040]. Kaplan-Meier survival analysis showed that the PFS in the low TSR group was significantly longer than that in the high TSR group (15.6 months vs. 10.2 months, χ2=13.84, P<0.001) . Univariate analysis showed that TSR value ( HR=0.29, 95% CI: 0.14-0.58, P<0.001) and brain metastasis ( HR=2.38, 95% CI: 1.12-5.05, P=0.024) were correlated with the worse prognosis of NSCLC patients. Multivariate Cox regression analysis showed that TSR value was an independent prognostic factor for NSCLC immunotherapy ( HR=0.32, 95% CI: 0.14-0.70, P=0.004) . Conclusion:TSR is an independent predictor of immunotherapy for NSCLC, but whether it can predict the short-term efficacy of immunotherapy for advanced NSCLC still needs further research.

Chloromethyl ether and diclomethyl ether are statutory substances that cause occupational lung cancer. From 2021 to 2022, the Department of Occupational Diseases of the Eighth People's Hospital of Hebei Province successively received 4 cases of lung cancer from a chemical company that required occupational disease diagnosis. All four patients had a clear occupational history of chloromethyl ether and diclomethyl ether for more than 1 year, diagnosis of primary small cell lung cancer supported by relevant histopathology, immunohistochemistry, and tumor markers. All the 4 patients were diagnosed as occupational lung cancer (chloromethyl ether, diclomethyl ether) .

Chloromethyl ether and diclomethyl ether are statutory substances that cause occupational lung cancer. From 2021 to 2022, the Department of Occupational Diseases of the Eighth People's Hospital of Hebei Province successively received 4 cases of lung cancer from a chemical company that required occupational disease diagnosis. All four patients had a clear occupational history of chloromethyl ether and diclomethyl ether for more than 1 year, diagnosis of primary small cell lung cancer supported by relevant histopathology, immunohistochemistry, and tumor markers. All the 4 patients were diagnosed as occupational lung cancer (chloromethyl ether, diclomethyl ether) .

Enzyme-catalyzed CO₂ reduction to value-added commodities is important for alleviating the global environmental issues and energy crises due to high selectivity and mild conditions. Owing to high energy density, formic acid or methanol produced from CO₂ using formate dehydrogenase (FDH) or multi-enzyme cascades are promising target chemicals for CO₂ utilization. However, the low activity, poor stability and low reusability of key enzymes involved in such process hampered its large-scale application. Enzyme immobilization provides an effective solution to these problems and significant progress have been made in immobilization carriers. Moreover, integration of enzyme immobilization with other catalysis techniques have been explored extensively. This review summarized the recent advances in the immobilization of enzymes using membranes, inorganic materials, metal-organic frameworks, covalent organic frameworks and other carriers, and illustrated the characteristics and advantages of different immobilization materials and immobilization methods. The synergistic effects and applications of immobilized enzymes and electrocatalytic or photocatalytic coupling reaction systems for CO₂ reduction were further summarized. Finally, the current challenges of enzyme immobilization technology and coupling reaction systems were pointed out and their development prospects were presented.
Enzymes, Immobilized ; Carbon Dioxide ; Catalysis ; Formate Dehydrogenases ; Metal-Organic Frameworks

Glycosite-specific antibody‒drug conjugatess (gsADCs), harnessing Asn297 N-glycan of IgG Fc as the conjugation site for drug payloads, usually require multi-step glycoengineering with two or more enzymes, which limits the substrate diversification and complicates the preparation process. Herein, we report a series of novel disaccharide-based substrates, which reprogram the IgG glycoengineering to one-step synthesis of gsADCs, catalyzed by an endo-N-acetylglucosaminidase (ENGase) of Endo-S2. IgG glycoengineering via ENGases usually has two steps: deglycosylation by wild-type (WT) ENGases and transglycosylation by mutated ENGases. But in the current method, we have found that disaccharide LacNAc oxazoline can be efficiently assembled onto IgG by WT Endo-S2 without hydrolysis of the product, which enables the one-step glycoengineering directly from native antibodies. Further studies on substrate specificity revealed that this approach has excellent tolerance on various modification of 6-Gal motif of LacNAc. Within 1 h, one-step synthesis of gsADC was achieved using the LacNAc-toxin substrates including structures free of bioorthogonal groups. These gsADCs demonstrated good homogeneity, buffer stability, in vitro and in vivo anti-tumor activity. This work presents a novel strategy using LacNAc-based substrates to reprogram the multi-step IgG glycoengineering to a one-step manner for highly efficient synthesis of gsADCs.