LONP1 ameliorates liver injury and improves gluconeogenesis dysfunction in acute-on-chronic liver failure / 中华医学杂志(英文版)

BACKGROUND@#Acute-on-chronic liver failure (ACLF) is a severe liver disease with complex pathogenesis. Clinical hypoglycemia is common in patients with ACLF and often predicts a worse prognosis. Accumulating evidence suggests that glucose metabolic disturbance, especially gluconeogenesis dysfunction, plays a critical role in the disease progression of ACLF. Lon protease-1 (LONP1) is a novel mediator of energy and glucose metabolism. However, whether gluconeogenesis is a potential mechanism through which LONP1 modulates ACLF remains unknown.@*METHODS@#In this study, we collected liver tissues from ACLF patients, established an ACLF mouse model with carbon tetrachloride (CCl 4 ), lipopolysaccharide (LPS), and D-galactose (D-gal), and constructed an in vitro hypoxia and hyperammonemia-triggered hepatocyte injury model. LONP1 overexpression and knockdown adenovirus were used to assess the protective effect of LONP1 on liver injury and gluconeogenesis regulation. Liver histopathology, biochemical index, mitochondrial morphology, cell viability and apoptosis, and the expression and activity of key gluconeogenic enzymes were detected to explore the underlying protective mechanisms of LONP1 in ACLF.@*RESULTS@#We found that LONP1 and the expressions of gluconeogenic enzymes were downregulated in clinical ACLF liver tissues. Furthermore, LONP1 overexpression remarkably attenuated liver injury, which was characterized by improved liver histopathological lesions and decreased serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in ACLF mice. Moreover, mitochondrial morphology was improved upon overexpression of LONP1. Meanwhile, the expression and activity of the key gluconeogenic enzymes were restored by LONP1 overexpression. Similarly, the hepatoprotective effect was also observed in the hepatocyte injury model, as evidenced by improved cell viability, reduced cell apoptosis, and improved gluconeogenesis level and activity, while LONP1 knockdown worsened liver injury and gluconeogenesis disorders.@*CONCLUSION@#We demonstrated that gluconeogenesis dysfunction exists in ACLF, and LONP1 could ameliorate liver injury and improve gluconeogenic dysfunction, which would provide a promising therapeutic target for patients with ACLF.

Application of Global Leadership Initiative on Malnutrition criteria in patients with liver cirrhosis / 中华医学杂志(英文版)

BACKGROUND@#The Global Leadership Initiative on Malnutrition (GLIM) criteria were published to build a global consensus on nutritional diagnosis. Reduced muscle mass is a phenotypic criterion with strong evidence to support its inclusion in the GLIM consensus criteria. However, there is no consensus regarding how to accurately measure and define reduced muscle mass in clinical settings. This study aimed to investigate the optimal reference values of skeletal muscle mass index for diagnosing sarcopenia and GLIM-defined malnutrition, as well as the prevalence of GLIM-defined malnutrition in hospitalized cirrhotic patients.@*METHODS@#This retrospective study was conducted on 1002 adult patients with liver cirrhosis between January 1, 2018, and February 28, 2022, at Beijing You-An Hospital, Capital Medical University. Adult patients with a clinical diagnosis of liver cirrhosis and who underwent an abdominal computed tomography (CT) examination during hospitalization were included in the study. These patients were randomly divided into a modeling group (cohort 1, 667 patients) and a validation group (cohort 2, 335 patients). In cohort 1, optimal cut-off values of skeletal muscle index at the third lumbar skeletal muscle index (L3-SMI) were determined using receiver operating characteristic analyses against in-hospital mortality in different gender groups. Next, patients in cohort 2 were screened for nutritional risk using the Nutritional Risk Screening 2002 (NRS-2002), and malnutrition was diagnosed by GLIM criteria. Additionally, the reference values of reduced muscle mass in GLIM criteria were derived from the L3-SMI values from cohort 1. Multivariate logistic regression analysis was used to analyze the association between GLIM-defined malnutrition and clinical outcomes.@*RESULTS@#The optimal cut-off values of L3-SMI were 39.50 cm 2 /m 2 for male patients and 33.06 cm 2 /m 2 for female patients. Based on the cut-off values, 31.63% (68/215) of the male patients and 23.3% (28/120) of the female patients had CT-determined sarcopenia in cohort 2. The prevalence of GLIM-defined malnutrition in cirrhotic patients was 34.3% (115/335) and GLIM-defined malnutrition was an independent risk factor for in-hospital mortality in patients with liver cirrhosis ( Wald = 6.347, P  = 0.012).@*CONCLUSIONS@#This study provided reference values for skeletal muscle mass index and the prevalence of GLIM-defined malnutrition in hospitalized patients with liver cirrhosis. These reference values will contribute to applying the GLIM criteria in cirrhotic patients.

Nephrotoxicity caused by polymyxin in the treatment of drug-resistant Gram-negative bacterial infections：a meta-analysis / 中国药房

OBJECTIVE To evaluate the incidence of nephrotoxicity in patients with drug-resistant Gram-negative bacterial infections after the use of polymyxin， and to provide evidence-based reference for clinical rational drug use. METHODS PubMed， Embase， Web of Science， the Cochrane Library， Wanfang database， CNKI， VIP and SinoMed were searched to collect randomized controlled trials （RCTs） or cohort studies about the polymyxin （trial group） versus other antibiotics （control group） or polymyxin B （trial group） versus polymyxin E （control group）. After literature screening， data extraction and quality evaluation， RevMan 5.4.1 software was used for meta-analysis. RESULTS A total of 37 studies were included， including 4 RCTs and 33 cohort studies， with a total of 5 871 patients. The meta-analysis results showed that in RCT [RR＝2.64，95%CI （1.43，4.87），P＝0.002] and in cohort studies [RR＝1.59， 95%CI （1.27， 1.98）， P＜0.000 1]， the incidence of nephrotoxicity in the trial group was significantly higher than control group. The results of the subgroup analysis of cohort studies showed that the incidence of nephrotoxicity in the trial group （receiving polymyxin） was significantly higher than control group （receiving new β-lactam and β-lactamase inhibitors and tigecycline）； when Kidney Disease Improving Global Outcomes （KDIGO）， renal replacement therapy or 0.5 times increase in serum creatinine were used as the standard of nephrotoxicity， the incidence of nephrotoxicity in the trial group was significantly higher than the control group （P＜0.05）. The incidence of nephrotoxicity in patients receiving polymyxin E was significantly higher than those using polymyxin B [RR＝0.57， 95%CI （0.39，0.84）， P＝0.005]. CONCLUSIONS In the treatment of drug-resistant Gram-negative bacteria infections， the incidence of nephrotoxicity caused by polymyxin is relatively high. The TYU108F）； incidence of nephrotoxicity caused by polymyxin E is higher than polymyxin B.

Practice and study on the establishment of transformation-oriented scientific research program in medical field: Taking a medical new research & development institution of Haihe Laboratory of Cell Ecosystem as an example / 中华医学科研管理杂志

Objective:To explore the innovation mode of independent transformation-oriented science and technology research program approval by medical new research & development (R&D) institution.Methods:Through analyzing the program layout, funds, review experts, undertaking units, chief experts and interdisciplinarity to summarize the experiences of the independent transformation-oriented municipal program approval by Haihe laboratory of Cell Ecosystem in 2022.Results:As a new medical R&D institution, which vigorously constructed by Tianjin, Haihe laboratory of Cell Ecosystem has carried out the practice of the independent transformation-oriented municipal program through the measures of layout of full-chain transformation, conducting transformation-oriented review, gathering high-level research talents, and emphasizing interdisciplinarity.Conclusions:The experiences of Haihe laboratory of Cell Ecosystem make significance for medical new R&D institutions to explore and cultivate scientific research program with transformation potential and to promote the transformation of scientific and technological achievements, which are powerful factors for new R&D institutions to play a role of pilot and provide important support to scientific and technological innovation and transformation.

Colonoscopy follow-up in patients with simultaneous multiple primary colorectal cancer and patients with sporadic colorectal cancer: a matched-pair study / 中华消化杂志

Objective:To investigate the incidences of metachronous advanced adenoma (MAA) in patients with simultaneous multiple primary colorectal cancer (CRC) and patients with sporadic CRC.Methods:From January 1, 2008 to September 30, 2022, at Beijing Shijitan Hospital, Capital Medical University, CRC patients who underwent surgery and 3 years follow-up with endoscopy were enrolled. The patients completed colonoscopy at least 2 times during follow-up in 6 to 36 months after surgery, and the interval between the 2 times colonoscopies was over 6 months. Clinical data including age, gender, and tumor location, stage, pathological features, combined underlying diseases, preoperative carcinoembryonic antigen, hemoglobin and other laboratory results, baseline colonoscopy results, and detection of MAA were collected. According to age (±2 years old), gender, location of primary lesion and stage of tumor, patients with simultaneous CRC or sporadic CRC were matched at 1∶1 ratio by propensity score matching. The cumulative risks of MAA in patients with simultaneous multiple primary CRC and patients with sporadic CRC were calculated. Cox proportional hazard regression was used to analyze the influencing factors in the occurrence of MAA.Results:A total of 814 CRC patients were enrolled and matched. After paired matching, there were 36 cases of simultaneous multiple primary CRC (78 lesions) and 78 cases of sporadic CRC (78 lesions). The cumulative incidences of MAA at 1, 2 and 3 years of simultaneous CRC group were 11.1%(4/36), 22.2%(8/36) and 33.3%(12/36), respectively. The cumulative incidences of MAA at 1-, 2- and 3-year of sporadic CRC group were 3.8%(3/78), 12.8%(10/78) and 20.5%(16/78), respectively.Simultaneous CRC was correlated with an increase in the 3-year cumulative incidence of MAA ( HR=4.163, 95% confidence interval(95% CI) 1.032 to 4.721, P=0.047). Especially in left-sided CRC, the risk of MAA in simultaneous CRC increased ( HR=7.186, 95% CI 1.602 to 20.787, P=0.010). The results of multivariate cox-regression analysis indicated that detection of simultaneous advanced adenoma at baseline endoscopy was an independent risk factor of MAA ( HR=3.175, 95% CI 1.411 to 7.142, P=0.005). Conclusion:Colouoscopy follow-up should be strengthened in patients with simultaneous multiple primary CRC and simultaneous advanced adenomas.

Prenatal diagnosis and intrauterine treatment of a giant fetal hepatic hemangioma:a case report / 中华围产医学杂志

This article reported a case of fetal giant hepatic hemangioma with cardiomegaly managed with intrauterine treatment. At 23 weeks of gestation, the patient was referred to Guangdong Women and Children Hospital due to abnormal abdominal echogenicity of the fetus, which was suspected to be a hepatic hemangioma or a hepatic arteriovenous fistula. The prenatal ultrasound at 26 weeks of gestation revealed an enlarged fetal hepatic hemangioma of 45 mm×35 mm×42 mm and an enlarged heart (cardiothoracic area ratio of 0.50). So, with the patient's informed consent, the fetus was treated with intrauterine administration of propranolol and dexamethasone and closely monitored by ultrasound. The volume of the lump still increased at the beginning of the medication, but started to shrink in the 7th week. Besides, the fetal cardiac load was reduced and the condition was controlled. The patient delivered at 37 weeks of gestation. The baby received a CT examination on the fourth day after birth which revealed an abdominal mass of 40 mm×30 mm×44 mm requiring no treatment, and no abnormalities were reported during a one-year follow-up.

Comparison of long-term clinical outcomes between transvaginal mesh and pelvic floor reconstruction with native tissue repair in the treatment of advanced pelvic organ prolapse / 中华妇产科杂志

Objective:To study the long-term clinical effect of transvaginal mesh (TVM) and pelvic floor reconstruction with native tissue repair (NTR) in the treatment of advanced pelvic organ prolapse (POP).Methods:Totally 207 patients with advanced POP who were treated in Hunan Provincial Maternal and Child Health Care Hospital from Jan. 2016 to Sep. 2019 were enrolled. The patient′s pelvic organ prolapse quantification were all at degree Ⅲ or above, and they all complained for different degree of symptoms. They were divided into two groups according to the different surgical methods, TVM group and NTR group. In TVM group, the mesh was implanted through the vagina for pelvic floor reconstruction, while in NTR group, the traditional transvaginal hysterectomy combined with uterosacral ligament suspension and anterior and posterior wall repair, as well as perineal body repair were performed. The median follow-up time was 60 months, during the follow up time, 164 cases (79.2%, 164/207) had completed follow-up, including 76 cases in TVM group and 88 cases in NTR group. The perioperative data and complication rates of the two groups were compared, and the subjective and objective outcomes of the two groups at 1, 3 and 5 years were observed, respectively. The objective efficacy was evaluated by three composite criteria, namely: (1) the distance from the farthest end of the prolapse of the anterior and posterior wall of the vagina to the hymen is ≤0 cm, and the descending distance of the top is ≤1/2 of the total length of the vagina; (2) determine the disappearance of relevant POP symptoms according to “Do you often see or feel vaginal mass prolapse？”; (3) no further operation or pessary treatment was performed due to prolapse. If the above three criteria were met at the same time, the operation is successful; otherwise, it was recurrence. The subjective efficacy was evaluated by the pelvic floor distress inventory-short form 20 (PFDI-20) and pelvic floor impact questionnaire-short form 7 (PFIQ-7).Results:The median follow-up time of the two groups was 60 months (range: 41-82 months). Five years after the operation, the subjective and objective cure rates of TVM group were 89.5% (68/76) and 94.7% (72/76), respectively. The subjective and objective cure rates in NTR group were 80.7% (71/88) and 85.2% (75/88), respectively. There were significant differences in the subjective and objective cure rates between the two groups ( χ2=9.869, P=0.002; χ2=3.969, P=0.046). The recurrence rate of TVM group was 5.3% (4/76), and that of NTR group was 14.8% (13/88). There was a significant difference between the two groups ( P=0.046). The postoperative PFDI-20 and PFIQ-7 scores of the two groups were significantly lower than those before surgery, and there were significant differences of the two groups before and after surgery (all P<0.05). Postoperative mesh exposure in TVM group was 1.3% (1/76). Conclusions:The long-term outcomes between the two groups show that the subjective and objective outcomes of pelvic floor reconstruction in TVM group are significantly higher than those in NTR group, and the recurrence rate is significantly lower than that in NTR group. TVM has certain advantages in the treatment of advanced POP.

Triaging patients in the outbreak of COVID-2019 / 中国感染控制杂志

In the outbreak of COVID-19,triage procedures based on epidemiology were implemented in a local hospital in Changsha to control the transmission of SARS-CoV-2 and avoid healthcare-associated infection.This re-trospective study analyzed the data collected during the triage period and found that COVID-19 patients were en-riched 7 folds into the Section A designated for patients with obvious epidemiological history.On the other side,nearly triple amounts of visits were received at the Section B for patients without obvious epidemiological history.8 COVID-19 cases were spotted out of 247 suspected patients.More than 50％of the suspected patients were submi-tted to multiple rounds of nucleic acid analysis for SARS-CoV-2 infection.Of the 239 patients who were diagnosed as negative of the virus infection,188 were successfully revisited and none was reported as COVID-19 case.Of the 8 COVID-19 patients,3 were confirmed only after multiple rounds of nucleic acid analysis.Besides comorbidities,delayed sharing of epidemiological history added complexity to the diagnosis in practice.The triaging experience and strategy will be helpful for the control of infectious diseases in the future.

The practice of cultivating gastroenterological postgraduates based on the innovation of "dual synergy ability" / 中华医学教育探索杂志

Under the background of "Medical Education Synergy", the clinical practice ability of postgraduates has been significantly improved, and the post competency has been enhanced. However, the "cultivation goal orientation" focuses on clinical practice, the education management department has weakened the cultivation of scientific research literacy, and the postgraduate tutors have not paid enough attention. As a result, the cultivation of scientific research literacy of professional degree postgraduates is seriously affected, and their scientific research ability is obviously weak. Taking gastroenterology as an example, by optimizing the course setting and rotation plan arrangement, attaching importance to the management of the graduate management department and the tutor responsibility system, and strengthening the application of interdisciplinary in the innovation and development of disciplines, we have explored an educational plan for cultivating professional degree postgraduates. The clinical practice and clinical research capabilities of postgraduates majoring in gastroenterology have been synergistically developed with remarkable results.

Mediating effect of psychological capital on rumination and learning burnout among undergraduate nursing students / 中华医学教育探索杂志

Objective:To investigate the effect of rumination on learning burnout of nursing undergraduate students and the mediating role of psychological capital between rumination and learning burnout of nursing undergraduate students.Methods:A total of 296 undergraduate nursing students from three medical colleges were assessed by using ruminative responses scale, learning burnout questionnaire and psychological capital scale. SPSS 20.0 was used for t-test. Pearson correlation was to analyze the relationship among psychological capital, learning burnout and ruminative thinking. AMOS 20.0 was used to construct and analyze the mediating model of psychological capital and its mediating effect was tested by Bootstrap method. Results:The average score of rumination of nursing undergraduate students was 46.60±11.40, learning burnout score was 56.18±11.25, and psychological capital scale score was 99.93±15.27. There was a significant difference among the rumination, psychological capital, and learning burnout scores in whether there was curriculum failure ( P < 0.05). The total score of rumination was positively related to the total score of learning burnout ( r = 0.39, P < 0.01), and was negatively related to the total score of psychological capital ( r = -0.53, P < 0.01). The total score of rumination was negatively related to the total score of psychological capital ( r = -0.46, P < 0.01). The psychological capital played a partial mediating role between rumination and learning burnout. The mediating effect value was 0.216, accounting for 61.521% of the total variation. Conclusion:The rumination can both directly affect the learning burnout of nursing undergraduate students and indirectly affect the learning burnout through psychological capital. Psychological capital plays a bridge role in improving rumination related to learning burnout.

Investigation on the cognition and training status of basic life support among county medical staff in Linfen, Shanxi Province / 中华急诊医学杂志

Objective:To understand the cognition and training status of basic life support among medical staff in Linfen, Shanxi Province, and to provide reference for the development of targeted training strategies and programs.Methods:A questionnaire survey was conducted among medical staff in 12 county hospitals in Linfen, Shanxi Province by convenience sampling method. The survey included the general characteristics of departments and medical staff, previous basic life support training assessment and cognitive status.Results:A total of 839 medical staff were included, 756 (90.1%) completed the survey, 183 (24.2%) were doctors and 573 (75.8%) were nurses. Most personnel lacked awareness of environmental safety, emergency response system start-up, adequate compression, airway management, and electrical defibrillation.Conclusions:The cognitive status of basic life support of medical staff in Linfen county is not optimistic. It is necessary to construct an applicable precision training course and retraining assessment system to improve the cognitive level and practical operation ability.

Qianjin Wenwu decoction suppresses renal interstitial fibrosis by enhancing the degradation of extracellular matrix in mice with unilateral ureteral obstruction / 中国天然药物

Diabetic kidney disease (DKD) is the most common complication of diabetes mellitus (DM). Qianjin Wenwu decoction (QWD), a well-known traditional Korean medicine, has been used for the treatment of DKD, with satisfactory therapeutic effects. This study was designed to investigate the active components and mechanisms of action of QWD in the treatment of DKD. The results demonstrated that a total of 13 active components in five types were found in QWD, including flavonoids, flavonoid glycosides, phenylpropionic acids, saponins, coumarins, and lignins. Two key proteins, TGF-β1 and TIMP-1, were identified as the target proteins through molecular docking. Furthermore, QWD significantly suppressed Scr and BUN levels which increased after unilateral ureteral obstruction (UUO). Hematoxylin & eosin (H&E) and Masson staining results demonstrated that QWD significantly alleviated renal interstitial fibrosis in UUO mice. We also found that QWD promoted ECM degradation by regulating MMP-9/TIMP-1 homeostasis to improve renal tubulointerstitial fibrosis and interfere with the expression and activity of TGF- β1 in DKD treatment. These findings explain the underlying mechanism of QWD for the treatment of DKD, and also provide methodological reference for investigating the mechanism of traditional medicine in the treatment of DKD.

Concerns of Technical Evaluation on Registration of All-inside Meniscus Suture System / 中国医疗器械杂志

OBJECTIVE@#To summarize the product registration declaration ideas and registration technical review of the all-inside meniscal suture system, and to systematically think about of the technical review concerns of the all-inside meniscal suture system products to provide technical guidance for improving the quality of registration and application and regulatory efficiency.@*METHODS@#Consult the public information of such products at home and abroad, and summarize the experience of registration review of such products.@*RESULTS@#The technical review of the all-inside meniscus suture system registration mainly focuses on product basic information, pre-clinical research, clinical evaluation and product technical requirements.@*CONCLUSIONS@#The difficulty of product registration and declaration of the all-inside meniscus suture system lies in the provision of pre-clinical research data of the product, and the applicant needs to strengthen the basic research ability, formulate scientific technical indicators and test methods to ensure the safety and effectiveness of the product, and also provide sufficient supporting data for the registration declaration.

Analysis of Revision Content and Evaluation Attentions on Guidance for Registration of Metallic Bone Plate Internal Fixation System (Revised in 2021) / 中国医疗器械杂志

This study briefly introduces the revised content of Guidance for Registration of Metallic Bone Plate Internal Fixation System (Revised in 2021) compared to the original guidance, mainly including the principles of dividing registration unit, main performance indicators of standard specification, physical and mechanical performance research, and clinical evaluation. At the same time, in order to provide some references for the registration of metallic bone plate internal fixation system, this study analyzes the main concerns in the review process of these products based on the accumulation of experience combining with the current review requirements.

Functions of CRABP2 in tumorigenesis and progression / 中国临床药理学与治疗学

Retinoic acid (RA) is a metabolic intermediate of vitamin A, which plays an important role in embryonic development and cell growth and differentiation. Cellular retinoic acid-binding proteins 2 (CRABP2) are a group of low-molecular weight intracellular proteins whose primary physiological function is to transport RA to the nucleus. Generally, CRABP2 binds to the retinoic acid receptor (RAR), then regulates specific downstream signaling pathways to function. Abnormal expression of CRABP2 was closely related to several human malignant tumors, and could affect the tumor occurrence and development through regulating multiple growth or apoptosis associated pathways or key biological molecules. Therefore, CRABP2 may be considered as a new diagnostic and prognostic marker for cancer, and a new therapeutic target for malignant tumors. Our present article summarizes the relationship between CRABP2 and tumor progression, drug resistance and prognosis, so as to provide reference for the future research.

The protective effect of terpinen-4-ol on inflammatory injury of VSMCs induced by high glucose through improving autophagic flux disorder / 中国药理学通报

Aim To investigate the effect of terpinen-4-ol (T40) on inflammatory injury of vascular smooth muscle cells (VSMCs) induced by high glucose based on the improvement of autophagic flow disorder and involved molecular signals. Methods The scratch test was used to analyze the migration ability of VSMCs, the levels of IL-1β and IL-6 in cell culture supernatant were measured by ELISA, the expression levels of inflammation-related proteins NF-κb p65, p-NF-κb p65, IL-1β, IL-18 and autophagy-related proteins p62, LC3-HYLC3-I, Beclinl, p-Beclinl were de-tected by Western blot. Results T40 inhibited migration of VSMCs induced by high glucose, reduced the secretion and release of pro-inflammatory factors IL-1β and IL-6, inhibited the expression of p-NF-κb p65/ NF-κb p65, IL-1β, IL-18, downregulated the expression of p62, LC3-TJ/LC3- I and p-Beclinl at same time. After interfering the autophagic flux of VSMCs with autophagy inhibitor chloroquine (CQ) , T40 pre-treatment significantly inhibited the protein expression levels of the above inflammatory factors and autophagy-related signals which mediated by CQ. Conclusion T40 inhibits the inflammatory injury of VSMCs induced by high glucose through improving the autophagic flow disorder.

The F-box-only protein 44 regulates pregnane X receptor protein level by ubiquitination and degradation

Pregnane X receptor (PXR) is a ligand-activated nuclear receptor that transcriptionally upregulates drug-metabolizing enzymes [e.g., cytochrome P450 3A4 (CYP3A4)] and transporters. Although the regulation of PXR target genes is well-characterized, less is known about the regulation of PXR protein level. By screening an RNAi library, we identified the F-box-only protein 44 (FBXO44) as a novel E3 ligase for PXR. PXR abundance increases upon knockdown of FBXO44, and, inversely, decreases upon overexpression of FBXO44. Further analysis revealed that FBXO44 interacts with PXR, leading to its ubiquitination and proteasomal degradation, and we determined that the F-box associated domain of FBXO44 and the ligand binding domain of PXR are required for the functional interaction. In summary, FBXO44 regulates PXR protein abundance, which has downstream consequences for CYP3A4 levels and drug-drug interactions. The results of this study provide new insight into the molecular mechanisms that regulate PXR protein level and activity and suggest the importance of considering how modulating E3 ubiquitin ligase activities will affect PXR-mediated drug metabolism.

Clinical application of retrograde thyroidectomy from top to bottom in retrosternal thyroid surgery / 临床耳鼻咽喉头颈外科杂志

Objective:To investigate the value of retrograde thyroidectomy from top to bottom in the operation of retrosternal thyroid surgery. Methods:Retrospective analysis was performed on the cases of retrosternal goiter excised by our surgeons from January 2017 to June 2022,the technical points, feasibility and advantages of the operation were summarized. Results:A total of 15 cases of retrosternal goiter treated by retrograde thyroidectomy were collected, including 5 cases of type Ⅰ retrosternal goiter and 10 cases of type Ⅱ retrosternal goiter.The postoperative pathology was benign. The surgical time is 40-60 minutes for unilateral retrosternal goiter and 70-90 minutes for bilateral goiter. All patients were discharged normally within 7 days after operation, and no operative complications were observed such as bleeding, hoarseness or hypoparathyroidism. Conclusion:This surgical excision method of thyroid is suitable for the type Ⅰ and type Ⅱ retrosternal goiter surgery, which can avoid the difficulties in exposing and separating the the inferior thyroid behind the sternum in conventional surgical method, speed up the operation and reduced the difficulty of operation, and has certain promotion value in clinic.

Expression, thermal stability modification and application in PHB degradation of polyhydroxyalkanoate depolymerase from Thermomonospora umbrina / 生物工程学报

Polyhydroxyalkanoate depolymerase (PHAD) can be used for the degradation and recovery of polyhydroxyalkanoate (PHA). In order to develop a PHAD with good stability under high temperature, PHAD from Thermomonospora umbrina (TumPHAD) was heterelogously expressed in Escherichia coli BL21(DE3). At the same time, a mutant A190C/V240C with enhanced stability was obtained via rational design of disulfide bonds. Characterization of enzymatic properties showed that the mutant A190C/V240C had an optimum temperature of 60 ℃, which was 20 ℃ higher than that of the wild type. The half-life at 50 ℃ was 7 hours, at 50 ℃ which was 21 times longer than that of the wild type. The mutant A190C/V240C was used for the degradation of polyhydroxybutyrate (PHB), one of the typical PHA. At 50 ℃, the degradation rate of PHB being treated for 2 hours and 12 hours was 2.1 times and 3.8 times higher than that of the wild type, respectively. The TumPHAD mutant A190C/V240C obtained in this study shows tolerance to high temperature resistance, good thermal stability and strong PHB degradation ability, which may facilitate the degradation and recovery of PHB.

Highly efficient production of L-valine by multiplex metabolic engineering of Corynebacterium glutamicum / 生物工程学报

As a branched chain amino acid, L-valine is widely used in the medicine and feed sectors. In this study, a microbial cell factory for efficient production of L-valine was constructed by combining various metabolic engineering strategies. First, precursor supply for L-valine biosynthesis was enhanced by strengthening the glycolysis pathway and weakening the metabolic pathway of by-products. Subsequently, the key enzyme in the L-valine synthesis pathway, acetylhydroxylate synthase, was engineered by site-directed mutation to relieve the feedback inhibition of the engineered strain. Moreover, promoter engineering was used to optimize the gene expression level of key enzymes in L-valine biosynthetic pathway. Furthermore, cofactor engineering was adopted to change the cofactor preference of acetohydroxyacid isomeroreductase and branched-chain amino acid aminotransferase from NADPH to NADH. The engineered strain C. glutamicum K020 showed a significant increase in L-valine titer, yield and productivity in 5 L fed-batch bioreactor, up to 110 g/L, 0.51 g/g and 2.29 g/(L‧h), respectively.