Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.

Objective:To investigate the value of serum free light chain(sFLC)and serum calcium ion in the diagnosis and prognosis of multiple myeloma(MM).Methods:Forty patients with MM treated in Henan Provincial People's Hospital from January 2018 to January 2022 were selected as the observation group,and 40 healthy volunteers were selected as the control group.The differences of sFLC-κ,sFLC-λ,sFLC-κ/λ,serum calcium ions,etc between the two groups were compared.Meanwhile,the differences of sFLC-κ,sFLC-λ,sFLC-κ/λ,serum calcium ions,etc in different international staging systems(ISS),chemotherapy efficacy and prognosis patients were analyzed.Results:The levels of sFLC-κ[(98.39±21.19)vs(12.01±4.45)mg/L],sFLC-λ[(210.20±45.54)vs(14.10±5.11)mg/L]and proportions of hypocalcemia(65％vs 0)in the observation group were significantly higher than those in the control group(P＜0.05),while sFLC-κ/λ ratio[(0.44±0.10)vs(0.87±0.12)]and serum calcium ions[(1.98±0.46)vs(2.42±0.40)mmol/L]were significantly lower than those in the control group(P＜0.05).The sFLC-κ,sFLC-λ,the proportion of hypocalcemia and the course of hypocalcemia in ISS stage Ⅲ patients in the observation group were significantly higher than those in stage Ⅰ and Ⅱ patients(P＜0.05),while sFLC-κ/λ ratio,and serum calcium ions were significantly lower than those in stage Ⅰ and Ⅱ patients(P＜0.05).The levels of sFLC-κ[(107.76±21.22)vs(94.67 ±20.11)mg/L],sFLC-λ[(245.54±41.12)vs(205.54±50.22)mg/L]of patients with hypocalcemia in the observation group was significantly higher than those without hypocalcemia(P＜0.05),while the sFLC-κ/λ ratio was significantly lower than those without hypocalcemia[(0.42±0.04)vs(0.47±0.06);P＜0.05].The levels of sFLC-κ[(107.29±20.14)vs(91.11±18.92)mg/L],sFLC-λ[(247.98±42.26)vs(179.29±39.32)mg/L]in patients with ineffective chemotherapy were significantly higher than those in patients with effective chemotherapy(P＜0.05),while the sFLC-κ/λ ratio was significantly lower than those in patients with effective chemotherapy[(0.43± 0.10)vs(0.50±0.09);P＜0.05)].The area under the ROC curve for sFLC-κ,sFLC-λ,sFLC-κ/λ predicting ineffective chemotherapy was 0.803,0.793 and 0.699 respectively,P＜0.05.There was no significant difference in sFLC-κ,sFLC-λ,sFLC-κ/λ ratio,serum calcium ion,hypocalcemia ratio and hypocalcemia course between survival and death patients(P＞0.05).Conclusion:sFLC and serum calcium are related to 1SS stage of MM patients.sFLC level has a certain value to predict the curative effect of chemotherapy in MM patients.However,the prognostic values of sFLC and serum calcium are not yet confirmed for MM patients.

Objective To explore the common features of Chinese ethnic groups.Methods Eight body indexes of 62 ethnic groups in China were analyzed.Results The cluster analysis showed that 52 males and 59 females ethnic groups were grouped into the mixed group dominated by the northern ethnic group and the mixed group dominated by the southern ethnic group.Eight Han ethnic groups were grouped into each group,but no Han group was aggregated.The result of body index classification showed that the main body types of Chinese male population were long trunk,middle chest,wide shoulder,wide pelvis and middle leg.Middle body,wide chest,wide shoulder,wide pelvis and middle leg were the main body types of Chinese female population.This showed that the characteristics of Chinese ethnic groups had obvious consistency.The consistency of Chinese group features was related to its close origin.It should be said that Han nationality played an important role in the process of communication and integration of various ethnic groups in China.In the history of the Han nationality,there had been many large-scale population migration.The southern movement of the northern ethnic minorities into the northern Han and the southward movement of the northern Han into the south promoted the formation of the Southern Han,which made the southern Han and the northern Han had similar body features,and also promoted the southern ethnic minorities into the southern Han.In addition,the Han nationality who moved into minority areas also gradually integrated into minority areas.Conclusion There are obvious commonalities in Chinese ethnic groups.

Objective:To investigate the application value of single-sperm sequencing in resolving the carrier status of preim-plantation genetic testing(PGT)for chromosomal structural rearrangements in Robertsonian translocations.Methods:Haplotypes were constructed by single-sperm isolation combined with single-sperm sequencing for a patient with 45,XY,der(13;14)(q10;q10).Twenty single-sperm samples were isolated by mechanical braking and subjected to whole-genome amplification(WGA),and then the Asian Screening Array(ASA)gene chip was used to detect the 183 708 single nucleotide polymorphisms(SNP)of the WGA products.The single sperm associated with the translocation that could be used as haplotype inference was detected by copy number variation(CNV)sequencing,and the chromosomal haplotypes with normal and Robertsonian translocations were inferred.Three biopsy samples of embryonic trophoblast cells were used as the objects.After whole-genome amplification,high-throughput sequencing was employed to determine the status of the translocation chromosome carried by the embryos.The available blastocysts were selected for transfer,and the amniotic fluid samples were taken at 18 weeks of gestation to confirm whether the fetus carried the pathogenic muta-tion.Results:A total of 6 037 SNP sites were screened by single-sperm sequencing,and 30 sites selected to distinguish normal and translocation haplotypes.Preimplantation haplotype analysis showed that all the three embryos were euploids without Robertsonian translocation chromosome.Genetic testing of amniotic fluid in the second trimester confirmed that the karyotype of the fetus was 46,XN,carrying no Robertsonian translocation chromosome.Conclusion:For male carriers of Robertsonian translocation,single sperm sequencing can be used to screen SNP sites to construct haplotypes for distinguishing normal and Robertsonian translocation em-bryos,and to provide a basis for embryo selection by preimplantation chromosomal structural genetic testing.

Humans ; Child ; Primary Myelofibrosis/genetics* ; Prognosis ; Mutation

Attenuated Salmonella typhimurium VNP20009 is a widely used natural oncolytic bacterium, which has great application potential given its unique characteristics, including clinical safety, tumor targeting specificity, and explicit genome sequence. Here, we show that tumor progression can be effectively reduced by intraperitoneal administration with VNP20009 in a mouse model of melanoma (all animal experiments were conducted in accordance with the Animal Ethics Committee of China Pharmaceutical University); co-culture experiment in vitro demonstrated that VNP20009 can induce the polarization of macrophage M1, accompanied by expression of inflammation-related factors; flow cytometry analysis showed that VNP20009 induced the increase of immune cell infiltration in tumor. Further analysis showed that T cells infiltration in tumor-draining lymph node (TDLN) increased, and VNP20009 induced the activation of CD4⁺ T cells and CD8⁺ T cells in tumor. Our results demonstrate that VNP20009 treatment significantly inhibited melanoma tumors by remodeling tumor-associated macrophages to an M1-like phenotype, as well as recruiting and activating cytotoxic T cells, combined with its own antigenic activity to exert anti-tumor immunity.

Objective:To investigate the effects of intravenous thrombolysis combined with Xingnaojing injection on hemodynamic indexes and neurological function in patients with cerebral infarction. Methods:A total of 142 patients with cerebral infarction who were treated in Xing An Meng Hospital from April 2020 to May 2021 were included in this study. They were randomly divided into a control group ( n = 71, intravenous thrombolysis) and a Xingnaojing injection group ( n = 71, intravenous thrombolysis + Xingnaojing injection). Intracranial arterial hemodynamic indexes, National Institutes of Health Stroke Scale score, Fugl-Meyer Assessment Scale score, serum inflammatory factors, oxidative stress indexes, brain injury markers, and the incidence of adverse reactions were compared between the two groups. Results:After treatment, serum levels of interleukin-1β, interleukin-6, and tumor necrosis factor-α were significantly lower in the Xingnaojing injection group than the control group [interleukin-1β: (4.05 ± 0.83) ng/L vs. (6.85 ± 1.02) ng/L, interleukin-6: (43.61 ± 5.14) ng/L vs. (60.31 ± 7.04) ng/L, tumor necrosis factor-α: (35.93 ± 4.25) ng/L vs. (20.93 ± 3.11) ng/L, t = 17.94, 16.14, 15.37, all P < 0.001]. After treatment, the mean blood flow velocities of the anterior cerebral artery, middle cerebral artery, and posterior cerebral artery in the Xingnaojing injection group were significantly higher than those in the control group [anterior cerebral artery: (49.36 ± 5.28) cm/s vs. (41.15 ± 5.12) cm/s, middle cerebral artery: (61.27 ± 7.02) cm/s vs. (50.19 ± 6.08) cm/s, posterior cerebral artery: (44.92 ± 5.63) cm/s vs. (37.26 ± 4.93) cm/s, t = 9.40, 10.05, 8.62, all P < 0.001]. After treatment, the National Institutes of Health Stroke Scale score and Fugl-Meyer Assessment Scale score in the Xingnaojing injection group were superior to those in the control group [National Institutes of Health Stroke Scale score: (10.36 ± 1.52) points vs. (14.62 ± 2.05) points, Fugl-Meyer Assessment Scale score: (76.19 ± 8.08) points vs. (65.28 ± 7.14) points, t = 14.06, 8.52, both P < 0.05]. After treatment, the serum level of malondialdehyde in the Xingnaojing injection group was significantly higher than that in the control group [(6.35 ± 1.02) μmol/L vs. (10.05 ± 1.63) μmol/L), t = 16.21, P < 0.001]. The serum level of superoxide dismutase in the Xingnaojing injection group was significantly lower than that in the control group [(114.31 ± 13.69) U/L vs. (92.25 ± 10.16) U/L), t = 10.90, P < 0.001]. Serum levels of neuron-specific enolase and S100β in the Xingnaojing injection group were significantly lower than those in the control group [neuron-specific enolase: (24.01 ± 3.24) IU/L vs. (30.31 ± 4.02) IU/L, S100β: (0.73 ± 0.17) ng/L vs. (1.13 ± 0.22) ng/L, t = 10.28, 12.12, both P < 0.001). There was a significant difference in the incidence of adverse reactions between the two groups ( P > 0.05). Conclusion:Intravenous thrombolysis combined with Xingnaojing injection for the treatment of cerebral infarction can improve intracranial hemodynamics, reduce the inflammatory response and oxidative stress, and alleviate brain tissue injury. The combined therapy is beneficial to protect the neurological function of patients with cerebral infarction and is highly safe.

Objective: To investigate the change in intestinal flora in Mongolian students with anxiety,so as to provide basis for exploring the relationship between flora and secretion expression in vivo. Methods: The Self rating Anxiety Scale(SAS)was used to assess anxiety in medical college students; then a semi structured interview was administered. Fecal samples that met the inclusion criteria were collected and divided into anxiety (SAS score≥50) and control groups (no anxiety, SAS score<50) according to the standard score of SAS. Samples provided by Mongolian female students were selected from each group. The total bacterial DNA was extracted from the fecal samples for PCR amplification and NovaSeq 2x250bp high throughput sequencing was performed for the V3- V4 region of 16S rDNA gene to obtain the biological information of the intestinal flora. The intergroup OTU, structural diversity, significant difference, and LEfSe analyses were performed with information mining of the literature think tanks. Results: Anxiety existed in 23.86% of the Mongolian students,and 16.96% of the Han people. A Chi square test showed no significant difference in detection of anxiety between Mongolian and Han college students ( P =0.07). Analysis of the alpha diversity index showed that the Shannon index, Simpson index, Chao1 index, and Observed species did not differed significantly between the two groups( t =8.0， 9.0 ，6.0，6.5). The difference in abundance of some bacteria was significant at the Class, Order, Family, and Genus levels between the two groups( t =-2.26-2.57，-5.08-3.58，-2.65-2.09， P <0.05). Conclusion The alpha diversity index showed that there was no significant difference in the abundance and diversity of intestinal flora between the two groups. While there were significant differences at different classification levels, the results suggest that the structure of intestinal flora can change in students with anxiety.

The present study focused on the potential mechanism of betulin (BT), a pentacyclic triterpenoid isolated from the bark of white birch (Betula pubescens), against chronic alcohol-induced lipid accumulation and metaflammation. AML-12 and RAW 264.7 cells were administered ethanol (EtOH), lipopolysaccharide (LPS) or BT. Male C57BL/6 mice were fed Lieber-DeCarli liquid diets containing 5% EtOH for 4 weeks, followed by single EtOH gavage on the last day and simultaneous treatment with BT (20 or 50 mg/ kg) by oral gavage once per day. In vitro, MTT showed that 0-25 mM EtOH and 0-25 μM BT had no toxic effect on AML-12 cells. BT could regulate sterolregulatory-element-binding protein 1 (SREBP1), lipin1/2, P2X7 receptor (P2X7r) and NOD-like receptor family, pyrin domains-containing protein 3 (NLRP3) expressions again EtOH-stimulation. Oil Red O staining also indicated that BT significantly reduced lipid accumulation in EtOH-stimulated AML-12 cells. Lipin1/2 deficiency indicated that BT might mediate lipin1/2 to regulate SREBP1 and P2X7r expression and further alleviate lipid accumulation and inflammation. In vivo, BT significantly alleviated histopathological changes, reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and triglyceride (TG) levels, and regulated lipin1/2, SREBP1, peroxisome proliferator activated receptor α/γ (PPARα/γ) and PGC-1α expression compared with the EtOH group. BT reduced the secretion of inflammatory factors and blocked the P2X7rNLRP3 signaling pathway. Collectively, BT attenuated lipid accumulation and metaflammation by regulating the lipin1/2-mediated P2X7r signaling pathway.

Objective: To investigate the repair effect and JNK/NF-κB,SOX9 mechanisms of vibration exercise with different frequencies on articular cartilage in rats with early knee osteoarthritis. Methods: Forty-eight adult male SD rats were randomly divided into six groups(n=8):model control group(MC),high frequency vibration group 1 (GP₁,60 Hz),high frequency vibration 2 group (GP₂,40 Hz),medium frequency vibration group (ZP,20 Hz),minor frequency group(DP,10 Hz)and normal control group(NC). Except for NC group,the rats in each group were made into early knee osteoarthritis model after six weeks of knee joint cavity injection of papain solution and 2% mixture l-cysteine on the 1^st,4 ^th and 7^th day. Each exercise group was subjected vibration to 40 minutes a day with amplitude of 2～5 mm and 5 days a week. Four weeks later, the articular cartilage of the lateral femoral condyle of the both back leg knee joints were detected by HE staining,serine O staining and Mankin scores for morphological observation. The expression levels of JNK,NF-κB p65 and Sox9 mRNA in articular cartilage of the medial femoral condyle were detected by RT-qPCR,and the protein expressions of JNK,NF-κB p65 and Sox9 were detected by Western blot. Results: Compared with the NC group,the Mankin score in other groups was significantly higher (P＜0.01). Compared with the MC group,the Mankin score of each vibration group was significantly lower(P＜0.05),the mRNA and protein expressions of JNK and NF-κB p65 in each vibration training group were significantly lower (P＜0.01),the expressions of Sox9 mRNA and protein in vibration training group were increased significantly (P＜0.01). Compared with the higher frequency group,the Mankin score,the mRNA and protein expressions of JNK and NF-κB p65 of lower frequency group were significantly lower (P＜0.05 or P＜0.01). But the expressions of Sox9 mRNA and protein were significantly higher (P＜ 0.05 or P＜0.01). Conclusion: Vibration exercise of different frequencies may present varying degrees of cartilage repair impact in rats with early knee osteoarthritis,and the cartilage repair by low-frequency vibration training is better than that by high-frequency vibration. This can be one of the mechanisms on controlling collagen synthesis by down-regulating JNK/NF-κB expression and increasing SOX9 activity of OA articular cartilage.
Animals ; Cartilage, Articular/metabolism* ; MAP Kinase Kinase 4 ; Male ; NF-kappa B/metabolism* ; Osteoarthritis, Knee/therapy* ; RNA, Messenger/metabolism* ; Rats ; Rats, Sprague-Dawley ; SOX9 Transcription Factor ; Vibration