Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 672
Filter
1.
Chinese Medical Journal ; (24): 190-199, 2024.
Article in English | WPRIM | ID: wpr-1007747

ABSTRACT

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.


Subject(s)
Animals , Humans , Mice , Acute-On-Chronic Liver Failure/pathology , ATP-Dependent Proteases/metabolism , Gluconeogenesis , Hepatocytes/pathology , Liver/metabolism , Mitochondrial Proteins/metabolism , Protease La/metabolism
2.
Chinese Medical Journal ; (24): 97-104, 2024.
Article in English | WPRIM | ID: wpr-1007737

ABSTRACT

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.


Subject(s)
Adult , Female , Humans , Male , Leadership , Liver Cirrhosis , Malnutrition/diagnosis , Nutritional Status , Retrospective Studies , Sarcopenia/diagnosis
3.
Chinese Journal of Medical Science Research Management ; (4): 266-272, 2023.
Article in Chinese | WPRIM | ID: wpr-995867

ABSTRACT

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.

4.
Chinese Journal of Digestion ; (12): 40-46, 2023.
Article in Chinese | WPRIM | ID: wpr-995424

ABSTRACT

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.

5.
Chinese Journal of Perinatal Medicine ; (12): 331-334, 2023.
Article in Chinese | WPRIM | ID: wpr-995105

ABSTRACT

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.

6.
Chinese Journal of Obstetrics and Gynecology ; (12): 595-602, 2023.
Article in Chinese | WPRIM | ID: wpr-992892

ABSTRACT

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.

7.
Chinese Journal of Infection Control ; (4): 295-303, 2023.
Article in Chinese | WPRIM | ID: wpr-991695

ABSTRACT

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.

8.
Chinese Journal of Medical Education Research ; (12): 504-507, 2023.
Article in Chinese | WPRIM | ID: wpr-991350

ABSTRACT

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.

9.
Chinese Journal of Medical Education Research ; (12): 297-301, 2023.
Article in Chinese | WPRIM | ID: wpr-991309

ABSTRACT

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.

10.
Chinese Journal of Emergency Medicine ; (12): 126-130, 2023.
Article in Chinese | WPRIM | ID: wpr-989795

ABSTRACT

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.

11.
Chinese Journal of Biotechnology ; (12): 1107-1118, 2023.
Article in Chinese | WPRIM | ID: wpr-970426

ABSTRACT

L-arabinose isomerase (L-AI) is the key enzyme that isomerizes D-galactose to D-tagatose. In this study, to improve the activity of L-arabinose isomerase on D-galactose and its conversion rate in biotransformation, an L-arabinose isomerase from Lactobacillus fermentum CGMCC2921 was recombinantly expressed and applied in biotransformation. Moreover, its substrate binding pocket was rationally designed to improve the affinity and catalytic activity on D-galactose. We show that the conversion of D-galactose by variant F279I was increased 1.4 times that of the wild-type enzyme. The Km and kcat values of the double mutant M185A/F279I obtained by superimposed mutation were 530.8 mmol/L and 19.9 s-1, respectively, and the catalytic efficiency was increased 8.2 times that of the wild type. When 400 g/L lactose was used as the substrate, the conversion rate of M185A/F279I reached a high level of 22.8%, which shows great application potential for the enzymatic production of tagatose from lactose.


Subject(s)
Galactose/metabolism , Limosilactobacillus fermentum/genetics , Lactose , Hexoses/metabolism , Aldose-Ketose Isomerases/genetics , Hydrogen-Ion Concentration
12.
Chinese Journal of Clinical Pharmacology and Therapeutics ; (12): 86-92, 2023.
Article in Chinese | WPRIM | ID: wpr-1014702

ABSTRACT

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.

13.
Chinese Pharmacological Bulletin ; (12): 532-536, 2023.
Article in Chinese | WPRIM | ID: wpr-1013826

ABSTRACT

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.

14.
Acta Pharmaceutica Sinica B ; (6): 4523-4534, 2023.
Article in English | WPRIM | ID: wpr-1011191

ABSTRACT

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.

15.
Journal of Clinical Otorhinolaryngology Head and Neck Surgery ; (12): 1011-1018, 2023.
Article in Chinese | WPRIM | ID: wpr-1011090

ABSTRACT

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.


Subject(s)
Humans , Thyroidectomy/methods , Retrospective Studies , Goiter, Substernal/pathology , Hypoparathyroidism/surgery
16.
Chinese Journal of Biotechnology ; (12): 3351-3363, 2023.
Article in Chinese | WPRIM | ID: wpr-1007962

ABSTRACT

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.


Subject(s)
Thermomonospora , Actinomycetales , Escherichia coli/genetics , Polyhydroxyalkanoates
17.
Chinese Journal of Biotechnology ; (12): 3253-3272, 2023.
Article in Chinese | WPRIM | ID: wpr-1007956

ABSTRACT

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.


Subject(s)
Valine , Corynebacterium glutamicum/genetics , Metabolic Engineering , Amino Acids, Branched-Chain , Bioreactors
18.
Chinese Journal of Biotechnology ; (12): 3236-3252, 2023.
Article in Chinese | WPRIM | ID: wpr-1007955

ABSTRACT

Succinic acid is an important C4 platform chemical that is widely used in food, chemical, medicine sectors. The bottleneck of fermentative production of succinic acid by engineered Escherichia coli is the imbalance of intracellular cofactors, which often leads to accumulation of by-products, lower yield and low productivity. Stoichiometric analysis indicated that an efficient production of succinic acid by E. coli FMME-N-26 under micro-aeration conditions might be achieved when the TCA cycle provides enough ATP and NADH for the r-TCA pathway. In order to promote succinic acid production, a serial of metabolic engineering strategies include reducing ATP consumption, strengthening ATP synthesis, blocking NADH competitive pathway and constructing NADH complementary pathway were developed. As result, an engineered E. coli FW-17 capable of producing 139.52 g/L succinic acid and 1.40 g/L acetic acid in 5 L fermenter, which were 17.81% higher and 67.59% lower than that of the control strain, was developed. Further scale-up experiments were carried out in a 1 000 L fermenter, and the titer of succinic acid and acetic acid were 140.2 g/L and 1.38 g/L, respectively.


Subject(s)
Escherichia coli/genetics , NAD , Succinic Acid , Acetic Acid , Adenosine Triphosphate
19.
Chinese Journal of Biotechnology ; (12): 3111-3124, 2023.
Article in Chinese | WPRIM | ID: wpr-1007948

ABSTRACT

L-homophenylalanine (L-HPA) is an important non-natural amino acid that has been used as a key intermediate for the synthesis of Puli drugs for the treatment of hypertension. At present, L-HPA is synthesized using chemical methods, which has the disadvantages of expensive raw materials, tedious steps and serious pollution. Therefore, researchers have conducted in-depth research on the enzymatic production of L-HPA. This review summarizes the research progress on the enzymatic synthesis of L-HPA, including the dehydrogenase process, the transaminase process, the hydantoinase process, and the decarboxylase process, with the hope to facilitate the industrial production of L-HPA.


Subject(s)
Amino Acids , Environmental Pollution , Industry , Protein Biosynthesis
20.
Chinese Acupuncture & Moxibustion ; (12): 277-281, 2023.
Article in Chinese | WPRIM | ID: wpr-969984

ABSTRACT

OBJECTIVE@#To observe the awakening effect and safety of Xingnao Kaiqiao (regaining consciousness and opening orifices) acupuncture on consciousness disorder in children with early severe traumatic brain injury (STBI) based on western medicine treatment.@*METHODS@#A total of 62 children with STBI were randomly divided into an observation group (31 cases,1 case dropped off) and a control group (31 cases, 1 case dropped off). The control group was treated with routine rehabilitation therapy (6 times a week for 30 days), and intravenous drip of cattle encephalon glycoside and ignotin injection (once a day for 28 days). On the basis of the treatment in the control group, the observation group was treated with Xingnao Kaiqiao acupuncture at Neiguan (PC 6), Shuigou (GV 26), Yintang (GV 24+), Baihui (GV 20), Sanyinjiao (SP 6), Zusanli (ST 36), etc., and supplementary acupoints according to clinical symptoms, once a day, 6 times a week for 30 days. The scores of Glasgow coma scale (GCS), coma recovery scale-revised (CRS-R) and modified Barthel index (MBI) were observed before treatment and 10, 20 and 30 d into treatment. Electroencephalogram (EEG) grading before and after treatment was observed in the two groups, and safety was evaluated.@*RESULTS@#After 10, 20 and 30 days of treatment, the scores of GCS, CRS-R and MBI in the two groups were increased compared before treatment (P<0.05), and those in the observation group were higher than the control group (P<0.05). After treatment, EEG grading of both groups was improved compared with that before treatment (P<0.05), and the observation group was better than the control group (P<0.05). There were no adverse events or adverse reactions in the two groups during treatment.@*CONCLUSION@#On the basis of western medicine treatment, Xingnao Kaiqiao acupuncture plays a remarkable role in wakening the early STBI children, can improve the level of consciousness disorder and daily living ability, and it is safe and effective.


Subject(s)
Humans , Child , Acupuncture Points , Acupuncture Therapy , Brain , Brain Injuries, Traumatic/therapy , Consciousness Disorders/therapy
SELECTION OF CITATIONS
SEARCH DETAIL