Optimizing Pichia pastoris protein secretion: Role of N-linked glycosylation on the α-mating factor secretion signal leader.

The methylotrophic yeast, Pichia pastoris (P. pastoris; syn. Komagataella spp.), known for its ability to grow to high cell densities, its strong and tightly regulated promoters, and mammalian liked secretion pathway, has been widely used as a robust system to secrete heterologous proteins. The α-mating factor (MF) secretion signal leader from Saccharomyces cerevisiae (S. cerevisiae) is currently the most successfully used secretion signal sequence in the P. pastoris system. In this study, the secretion efficiency mediated by the α-MF secretion signal leaders from Komagataella pastoris (K. pastoris) and Komagataella phaffii (K. phaffii) was assessed using Enhanced Green Fluorescent Protein (EGFP) as a reporter. The results indicated that the secretion efficiency associated with the α-MF secretion signal leaders from K. pastoris and K. phaffii was notably lower in comparison to the α-MF secretion signal leader from S. cerevisiae. Further research indicated that N-linked glycosylation of the α-MF secretion signal leader enhanced the secretion of EGFP. Disruption of calnexin impaired the secretion of EGFP mediated by the N-linked glycosylated α-MF secretion signal leader, without affecting EGFP secretion mediated by the non-N-linked glycosylation α-MF secretion signal leader. The N-linked glycosylated of the α-MF secretion signal leader reduced the unfolded protein response (UPR) in the endoplasmic reticulum (ER). The enhancement of EGFP secretion by the N-linked glycosylated α-MF secretion signal leader might be achieved through the acceleration of proper folding of glycoproteins by the molecular chaperone calnexin. This study enhances the understanding of protein secretion in P. pastoris, specifically highlighting the influence of N-linked glycosylation on secretion efficiency, and could have implications for the production of recombinant proteins in bioengineering and biotechnological applications in P. pastoris.

Chaihu Longgu Muli Decoction for post-stroke insomnia: A protocol for systematic review and meta-analysis.

BACKGROUND: Poststroke insomnia (PSI) is a frequent complication of stroke usually as a comorbidity of poststroke depression and mainly occurs within the first 6 months after stroke.[1] Addressing PSI to improve stroke prognosis is of great value. Herbal medicine like Chaihu Longgu Muli Decoction (CLMD), which is commonly considered to be a good treatment for depression and epilepsy, has the therapeutic potential on PSI; however, insufficient systematic reviews were conducted to testify its efficacy. Therefore, the objective of this paper is to provide reliable evidence of the efficacy and safety of CLMD on PSI and a foundation for further investigation. METHODS: The literature of clinical randomized controlled trials (RCTs) regarding CLMD for PSI published before June of 2021 will be retrieved in the databases, and 2 investigators will be asked to collect and crosscheck the data independently. For the including studies, the quality evaluation on methodology will be assessed in the light of the Cochrane Handbook for Systematic Review of Interventions V.5.1.0 as well as the quality of evidence will be evaluated by the Grading of Recommendations Assessment, Development, and Evaluation. Besides, the assessment of heterogeneity and reporting bias, the sensitivity analysis and the subgroup analysis will be conducted. Stata 15 will be applied to analyze the above data. RESULTS: The review will conduct a high-quality synthesis on present evidence of CLMD for PSI. CONCLUSION: The conclusion of the study will indicate whether CLMD is effective and safe for PSI.

Prophylactic Norepinephrine Infusion Reduces Postoperative Complications and Hospitalization Time in Elderly Patients Undergoing Posterior Lumbar Spinal Fusion.

This single-center prospective randomized controlled trial explores the effect of prophylactic norepinephrine infusion on the incidence of complications and hospitalization time in elderly patients (60-85 years old) undergoing posterior lumbar spinal fusion. In total, 129 elderly patients were randomized into two groups: a group that received norepinephrine during general anesthesia and a control group not receiving norepinephrine. The primary outcomes were in-hospital complications and 90-day postoperative complications and hospitalization time. The results show that in-hospital complications occurred in 24 of 60 patients (40%) in the control group versus 11 of 60 patients (18.3%) in the norepinephrine group (RR, 2.182; 95% CI, 1.177-4.045; P = 0.015). Cardiac events occurred significantly more frequently in the control than in the norepinephrine group. Total number of patients experiencing complications within 90 days postoperatively was lower in the norepinephrine (11 of 60; 18.3%) than in the control group (26 of 60; 43.3%; RR, 2.364; 95% CI, 1.288-4.339; P = 0.005). The median length of hospital stay was 17 days (11-27) in the control group and 15 days (10- 23) in the norepinephrine group (P = 0.01). The secondary outcomes were serum levels of syndecan-1, hyaluronic acid, heparan sulfate, and brain natriuretic peptide. Logistic regression analysis is used to describe the relationship between selected independent variables and in-hospital complications. Intraoperative total fluid, crystalloid, and colloid volumes were significantly higher in the control than in the norepinephrine group. The patients in the norepinephrine group had a higher MAP but a lower heart rate than those in the control group after the induction of anesthesia and intraoperatively. Syndecan-1, hyaluronic acid, and heparan sulfate serum levels showed a different course in the two groups. In conclusion, prophylactic norepinephrine infusion during posterior lumbar spinal fusion is preferable for elderly patients undergoing lumbar spinal fusion under general anesthesia. It can reduce postoperative complications and hospitalization time by reducing the injury to the vascular endothelium. This trial is registered with Clinical Trial Registration http://www.chictr.org.cn/showproj.aspx?proj=33660, identifier ChiCTR-1900021309.

Topiramate for hypoxic ischemic encephalopathy: A systematic review protocol.

BACKGROUND: Hypoxic ischemic encephalopathy (HIE) is brain injury caused by different reasons and the most common diagnosed is neonatal HIE. Most of the existing treatments have their own shortcomings or there are still some unexplained mechanisms in it. Topiramate (TPM) is a new drug for the treatment for seizures in neonates with HIE, but is currently used off-label. Our protocol aims to access the efficiency and safety of TPM for HIE. METHODS AND ANALYSIS: Eight databases will be searched by 2 independent researchers for the article on the topic of using TPM as treatment for HIE, including PubMed, the Cochrane Central Register of Controlled Trials (Cochrane Library), Embase, and Web of Science, China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database (CBM), Wang Fang Database and Chinese Science and Technology Periodical database (VIP). The included papers are those published from the established date of the databases to 2019. The therapeutic effects based on the grade of neonatal behavioral neurological assessment will be regarded as the primary outcomes. RevMan V5.3 will be used to compute the data synthesis and carry out meta-analysis. The risk of bias will be appraised by the Cochrane risk of bias tool. Rare ratio for dichotomous outcomes and mean different for continuous data will be expressed with 95% confidence intervals (CI) for analysis. A random effects model or a fixed effects model will be employed, when heterogeneity is found or not. Subgroup analysis and sensitivity analysis will be applied if the heterogeneity is obvious. RESULTS: This study will provide the recent evidence of TPM for HIE from reducing seizure acticity. CONCLUSION: The conclusion of this study will provide proof to evaluate if TPM is effective and safe in the treatment of HIE.PROSPERO registration number: PROSPERO CRD42018117981.

Taohong Siwu decoction for femoral head necrosis: A protocol for systematic review.

BACKGROUNDS: Femoral head necrosis is one of the most common orthopedic diseases which can be diagnosed in all ages with different reasons. Taohong Siwu decoction (TSD) has been widely used in the treatment of femoral head necrosis. However, as far as we know, there is still a lack of supporting evidence regarding the efficacy of TSD for femoral head necrosis. Therefore, this protocol aims to evaluate the effectiveness and safety of TSD for femoral head necrosis. METHODS: Eight electronic databases, including PubMed, the Cochrane Central Register of Controlled Trials, EMBASE, Web of Science, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, Technology Periodical database, (Chinese Scientific Journal Database) and Wanfang Database will be searched from the time when the respective databases were established to January 2020. Randomized controlled trials of TSD in the treatment of femoral head necrosis will be collected. After evaluating the quality of methodology and extracting valid data, the final meta-analysis will be carried out with software Revman 5.3. ETHICS AND DISSEMINATION: The results of this systematic review will offer implications of the use of TSD treatment for Femoral Head Necrosis. It uses aggregated published data instead of individual patient data and does not require an ethical board review and approval. The findings will be published in a peer-reviewed journal and disseminated in conference presentations. RESULTS: The results of this study will offer implications of the use of TSD treatment for FHN with this meta-analysis. CONCLUSION: The conclusion of this study will provide recent evidence to assess whether TSD is effective and safe in the treatment of FHN.

Efficacy and safety of core stability training on gait of children with cerebral palsy: A protocol for a systematic review and meta-analysis.

BACKGROUND: Cerebral palsy (CP) is a common disability in children featured with pathological gait and limb function limitation due to muscle weakness. Improving limb function and quality of life is currently considered to be highlighted. Physiotherapy is a chief component of rehabilitation for children with CP, correcting gait and improve walking capacity through muscle strength training. Standard rehabilitation programs for CP have not been determined. Core stability training (CST), which coordinates limb balance via trunk control, is widely used in sports competition. And it is gradually introduced into the rehabilitation of children with cerebral palsy with a positive impact on the patients' gait performance. By screening published literatures, this study aims to conduct a meta-analysis to systematically evaluate the effectiveness and safety of CST in gait of children with CP. METHODS: Randomized controlled trials (RCTs) and controlled clinical trials (CCTs) on CST in the treatment of children with CP were searched from 6 databases. Moreover, the reference lists of conference papers and included literatures will be manually searched to avoid omissions. Literature screening and data extraction were performed independently by 2 researchers. RCTs carry out the risk of bias analysis evaluation from seven aspects through the Cochrane Collaboration's risk of bias tool. Fixed or random effect model will be performed to analyze the outcomes. When higher heterogeneity occurs (I > 50%), the sensitivity or subgroup analysis will also be conducted to find potential factors. And the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach is used for assessing the quality of evidence. RESULTS: The study will evaluate the effect of CST on gait of children with CP from multiple outcomes, including walking speed, endurance, stride length, and safety. CONCLUSION: Based on evidence-based medicine, the conclusion of this study can demonstrate the effectiveness and safety of CST in gait correction for children with CP. PROSPERO REGISTRATION NUMBER: PROSPERO CRD 42019134094.

[Analysis on regularity of traditional Chinese patent medicine in treating hyperlipidemia].

To explore the regularity of traditional Chinese patent medicines for the treatment of hyperlipidemia recorded in Newly Edited National Chinese Traditional Patent Medicines,the Composition Principles of Chinese Patent Drugs,New Drug Conversion Standard,the Compilation of National Standard for Traditional Chinese Medicines and Chinese Pharmacopoeia. Researchers extracted the information of prescriptions from these cases according to the inclusion and exclusion criteria. Then microsoft excel 2010 was used to conduct frequency statistics and count the frequency of traditional Chinese medicine. SPSS Clementine( ver.12. 0) and SPSS( ver. 18. 0)were adopted respectively for frequency analysis,association rules analysis,cluster analysis and factor analysis. Besides,KMO test and Bartlett spherical test were performed for factor adaptation test. Finally,a total of 173 traditional Chinese medicines were included,involving 94 Chinese patent medicine prescriptions. The frequency results of traditional Chinese medicine showed that there were 33 kinds of high-frequency traditional Chinese medicine,mainly including those for tonifying medicine,activating blood and resolving stasis and blood-stasis,and clearing damp. The association rules analysis found out 12 association rules of drug pairs,3-herb pairs of 25 and4-herb pairs of 6. Totally 11 medicine groups with relevance were respectively extracted by cluster analysis. KMO test and Bartlett spherical test indicated that the method was suitable for factor analysis and 11 common factors were respectively extracted by factor analysis. The association rules reflected the therapeutic method for tonify the liver and kidney,activating blood and resolving stasis. Cluster analysis and factor analysis showed the therapeutic method of Qi-enriching and Yin-nourishing,and the factor analysis focused more on removing blood stasis and dampness. The decision tree with hawthorn as the dependent variable reflects the importance of alisma orientalis and fructus schisandrae in the drug matching. In conclusion,data mining technique can comprehensively analyze the regularity of prescriptions of traditional Chinese patent medicine for hyperlipidemia,and is helpful for guiding the development of Chinese patent medicines and the clinical practice of traditional Chinese medicine.

Dexmedetomidine activates the PI3K/Akt pathway to inhibit hepatocyte apoptosis in rats with obstructive jaundice.

Obstructive jaundice (OJ) is a common disease in clinical surgery. The present study aimed to determine the effects of dexmedetomidine (Dex) on hepatocyte apoptosis in rats with OJ and also to explore the underlying mechanism. A total of 30 adult male Sprague Dawley rats were randomly divided into 3 groups: Sham group, bile duct ligation (BDL) group, and BDL+Dex group. The serum liver function index, expression levels of serum inflammatory factor interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), and the liver pathological changes were compared amongst groups. The serum liver function index and expression levels of inflammatory factors in the BDL group and BDL+Dex group were higher compared with the sham group. The serum liver function index and expression levels of inflammatory factors were lower in the BDL+Dex group compared with the BDL group. The severity of hepatic injury was diminished in the BDL+Dex group compared with the BDL group. Compared with the sham group, the hepatocyte apoptosis rate increased significantly in the BDL group and BDL+Dex group. The present findings suggested that Dex improved the liver function of rats with OJ, reduced the production of inflammatory factors and inhibited the apoptosis of hepatocytes. Dex demonstrated a protective effect on liver damage potentially via activation of the phosphoinositide 3-kinase/protein kinase B signaling pathway.

Dexmedetomidine Attenuates Lung Injury in Obstructive Jaundice Rats Through PI3K/Akt/HIF-1α Signaling Pathway.

BACKGROUND: Obstructive jaundice (OJ) could seriously affect the biochemical and immune functions in the body. Up to now, there are still poor evidences about the role of dexmedetomidine in OJ. METHODS: Male Wistar rats were divided into four groups: Sham operation group (Sham group, n = 10), obstructive jaundice group (OJ group, n = 10), OJ + dexmedetomidine group (D group, n = 10), OJ+ dexmedetomidine +LY294002 group (DL group, n = 10). The expressions of phospho-Akt(p-Akt), HIF-1α(hypoxia inducible factor-1α), Akt mRNA, HIF-1αmRNA, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in different groups were evaluated. RESULTS: The lung injury score was decreased in OJ group compared with that in DL group. The expression of the HIF-1α protein, p-Akt protein, Akt mRNA, and HIF-1α mRNA in OJ group were significantly increased (p <0.05) (vs. S group). Meanwhile, these protein molecular were significantly higher in the D group than that in OJ group (p <0.05). However, the mRNA expressions of these molecular in OJ group were significantly lower than that in D group (p <0.05). The concentrations of IL-6 and TNF-α in OJ group and D group was significantly up-regulated compared with that in S group (p <0.05). Meanwhile, IL-6 and TNF-α concentrations were significantly up-regulated in DL group compared with that in group D (p <0.05). The concentrations of IL-6 and TNF-α were significantly decreased in the D group and DL group compared with that in OJ group (p <0.05). CONCLUSION: Dexmedetomidine can attenuate lung injury in obstructive jaundice rats through PI3K/Akt/HIF-1α signaling pathway. Meanwhile, dexmedetomidine can reduce the concentrations of IL-6 and TNF-α in obstructive jaundice rats.

Preventive Effects of Dexmedetomidine on Renal Dysfunction and Hemodynamic Stability in Malignant Obstructive Jaundice Patients During Peri-Operative Period.

BACKGROUND This study aimed to investigate effects of intra-operative administration with dexmedetomidine (Dex) on hemodynamics and renal function in patients with malignant obstructive jaundice. MATERIAL AND METHODS Our randomized, double-blinded, placebo-controlled study was conducted among 40 patients with malignant obstructive jaundice between August 2009 and March 2011 in The Affiliated Hospital of Inner Mongolia Medical University. The 40 patients were randomly divided into 2 groups: the Dex group (receiving Dex 0.5 µg/kg 10-minutes before induction and then a 0.5 µg/kg/hour maintenance infusion until end of operation 30 minutes) and the Control group (receiving normal saline of same amount and at same rate). The adverse events, including incidence of cardiovascular complications and nausea and vomiting, and length of hospital stay were determined. The level of cystatin C (CysC), retinol-binding protein (RBP), creatinine (Scr), and blood urea nitrogen (BUN) were also evaluated. RESULTS Dexmedetomidine administration significantly decreased heart rate (HR) and stroke volume variation (SVV) and significantly increased capital venous pressure (CVP) and mean arterial pressure (MAP) values compared to that in the Control group (P<0.05). Dexmedetomidine administration significantly upregulated urine volume and significantly downregulated atropine levels compared to the Control group (P<0.05). Dexmedetomidine administration significantly improved renal functions, by modulating CysC, RBP, Scr and BUN levels compared to the Control group (P<0.05). Dexmedetomidine administration demonstrated no additional side-effects. Dexmedetomidine administration significantly shortened length of hospitalization in the Dex group compared to the Control group (P<0.05). CONCLUSIONS Dexmedetomidine plays preventive effects on renal dysfunction and hemodynamic stability in malignant obstructive jaundice patients during peri-operative period.

Current Therapy of Drugs in Amyotrophic Lateral Sclerosis.

Amyotrophic lateral sclerosis (ALS), commonly termed as motor neuron disease (MND) in UK, is a chronically lethal disorder among the neurodegenerative diseases, meanwhile. ALS is basically irreversible and progressive deterioration of upper and lower motor neurons in the motor cortex, brain stem and medulla spinalis. Riluzole, used for the treatment of ALS, was demonstrated to slightly delay the initiation of respiratory dysfunction and extend the median survival of patients by a few months. In this study, the key biochemical defects were discussed, such as: mutant Cu/Zn superoxide dismutase, mitochondrial protectants, and anti-excitotoxic/ anti-oxidative / antiinflammatory/ anti-apoptotic agents, so the related drug candidates that have been studied in ALS models would possibly be further used in ALS patients.