The present study aimed to establish an LC-MS/MS method for the quantification of tiamulin in minipig plasma and to further conduct a pharmacokinetic comparison of different formulations. The plasma samples were extracted with acetonitrile (meloxicam as internal standard), separated on a C18 column, and quantified by multiple reaction monitoring mode (ESI+). Sanyuan minipigs were used as experimental animals. Plasma samples were collected after intravenous injection (10 mg/kg) and intragastric administration (20 mg/kg). The method showed good linearity, with intra- and inter-batch RSD of 1.00%–8.13% and RE within ±15%. The extraction recovery, matrix effect and stability of the analytical methods met the relevant requirements. Tiamulin fumarate active pharmaceutical ingredient was intravenously administered, with c0 of about (4383.73±2676.78) ng/mL, AUC0-t of about (4803.50±965.68) h·ng/mL, t1/2 of about (4.66±1.68) h, and CL of about (2.14±0.46) L/(kg·h). Three tiamulin formulations were intragastrically administered, with cmax of (552.00±328.55), (545.00±136.97) and (590.60±237.02) ng/mL, tmax of (1.47±0.68), (0.69±0.75) and (0.72±0.72) h, and F of 24.85%, 15.28% and 16.97%, respectively. The validated method meets the requirements for biological sample analysis and is applicable for the pharmacokinetic evaluation of tiamulin formulations in minipigs.

Amide bond is formed by dehydration and condensation of amino and carboxyl groups in a molecule, which is used in structural design of drugs. The stability of the amide bond is affected by many factors, which make the pharmacokinetic behaviors of amide drugs complicated by metabolic heterogeneity. This review proposes that the expression and activity of hydrolase may be one of the important reasons for the obvious differences in the pharmacokinetics of amides among species, summarizes the common metabolic enzymes or proteins responsible for hydrolyzing amides so as to provide some reference for the structural design and further clinical study of amide drugs, and suggests that improper selection of in vitro evaluation systems may be an important cause for the inconsistency between between in vitro and in vivo pharmacokinetic characteristics of drugs, with a summary of the currently used in vitro drug metabolism systems for drug evaluation, aiming to provide a basis for preclinical evaluation of drugs.

Objective:To explore the related factors affecting the prognosis of children with parenteral nutrition-associated cholestasis (PNAC).Methods:Twenty children with PNAC admitted to Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology from January 2014 to December 2020 were selected as research objects by retrospective study. According to prognosis, children were divided into good (15 cases) and poor prognosis group (5 cases). Clinical data such as general condition, intravenous nutrition duration, related biochemical examination indexes and main treatment methods of children in the two groups were collected. Spearman correlation analysis was used to quantify the correlation between alanine aminotransferase (ALT) and poor prognosis. Univariate analysis was used to analyze the risk factors affecting the prognosis of children with PNAC, and receiver operating characteristic curve (ROC curve) was drawn to evaluate the predictive value of ALT on the prognosis of children.Results:There were no significant differences in gender, body weight, gestational age, age, feeding mode, duration of intravenous nutrition, direct bilirubin (DBil), aspartate aminotransferase (AST), γ-glutamyltranspeptidase (GGT), total protein (TP), serum albumin (Alb), globulin (GLB), alkaline phosphatase (ALP), platelet count (PLT), white blood cell count (WBC), red blood cell count (RBC), hemoglobin (Hb), lymphocyte count (LYM), urine culture, AST/PLT ratio (APRI) and main treatment methods between the two groups. Total bilirubin (TBil), ALT, neutrophil count (NEU) and monocyte count (MONO) in the good prognosis group were significantly lower than those in the poor prognosis group [TBil (μmol/L): 120.00±48.63 vs. 175.26±29.14, ALT (U/L): 73.25±44.29 vs. 145.30±74.33, NEU (×10 9/L): 2.55±1.29 vs. 5.08±4.10, MONO (×10 9/L): 1.23±0.87 vs. 2.13±0.60, all P < 0.05]. Logistic regression analysis showed that ALT was the risk factor affecting the prognosis of children with PNAC, when ALT increased by 1 U/L, the probability of poor prognosis increased by 3.6% [odds ratio ( OR) = 1.04, 95% confidence interval (95% CI) was 1.00-1.07, P = 0.04]. Spearman correlation analysis showed that the incidence of poor prognosis was positively correlated with ALT ( r = 0.49, P = 0.03). ROC analysis showed that ALT had certain predictive value for the prognosis of children with PNAC [area under ROC cure (AUC) = 0.83, 95% CI was 0.00-1.00, P = 0.03]; when the cut-off value was 121.50 U/L, its sensitivity was 80% and specificity was 93%, suggesting that ALT could be used as the main indicator for clinical prediction of poor prognosis for PNAC. Conclusion:ALT is an independent risk factor of poor prognosis in children with PNAC.

The solute carrier (SLC) consists of more than 400 transport proteins mediating the influx and efflux of ions, nucleotides, sugars and other exogenous and endogenous substances across biological membranes. Over 80 SLC carrier proteins have been reported to be closely associated with human diseases, in which more than 30 SLC proteins have been regarded as the potential drug targets. SLC13A5 mediates transmembrane transport of substances such as citrate, which is connected with de novo lipid synthesis (DNL). Studies have found that SLC13A5 is related to metabolic diseases such as obesity, insulin resistance (IR), non-alcoholic fatty liver disease (NAFLD). At present, there is no specific drug for clinical treatment of metabolic diseases caused by lipid metabolism disorders, especially NAFLD. Therefore, this paper summarizes the effect of SLC13A5 on metabolic regulation and its potential as a pharmacological target for metabolic diseases treatment, aiming to provide a reference for the research and development of drugs related to metabolic diseases.

Objective:To investigate the clinical manifestations and characteristics of children infected with 2019 novel coronavirus (2019-nCoV) in Wuhan City.Methods:The clinical data of 146 children diagnosed with 2019 novel coronavirus infection by nasopharyngeal swab real-time reverse transcription polymerase chain reaction in Wuhan Children′s Hospital, Tongji Medical College, Huazhong University of Science and Technology from January 21 to February 24, 2020 were retrospectively analyzed. The basic data, clinical symptoms, laboratory examinations, pulmonary imaging, clinical classification, treatment medication and the prognosis of disease were included for analysis.Results:Among the 146 cases, 86 (58.9%) were males and 60 (41.1%) were females, with a median age of 6 years and 10 months.Three cases (2.1%) had a history of underlying diseases, 127 cases (87.0%) had a clear history of infected family clusters, and two cases (1.4%) had a history of exposure with Huanan Seafood Wholesale Market in Wuhan City. The clinical classifications included 20 asymptomatic cases (13.7%), 26 mild cases (17.8%), 99 ordinary cases (67.8%), and one critical case (0.7%). A total of 146 patients were tested positive for nasopharyngeal swabs by 2019-nCoV nucleic acid. Among them, 10 patients had a negative nasopharyngeal swab nucleic acid test before diagnosis, and one of them had a negative nasopharyngeal swab nucleic acid test for two consecutive times. The initial symptoms were mainly fever (59 cases, 40.4%) and cough (52 cases, 35.6%). Thirteen cases (8.9%) showed decreased leukocyte counts and three cases (2.1%) showed decreased lymphocyte counts. In addition, aspartate aminotransferase increased in 23 cases (15.8%), serum creatinine increased in seven cases (4.8%), lactic acid dehydrogenase increased in 26 cases (17.8%), and C reactive protein increased in 38 cases (26.0%). Fifty-nine cases (40.4%) were tested positive for IgM antibody to Mycoplasma pneumoniae. One hundred cases (68.5%) were abnormal in pulmonary imaging and 50 cases (34.2%) presented with multiple frosted glass shadows. All the 146 children were given general treatment, and the antiviral treatment was mainly interferon or interferon combined with oral medication. As of February 24, 2020, 72 cases (49.3%) were discharged from the hospital after reaching the de-isolation standard, with a median length of stay of 10 days, and there was no death case.Conclusions:Children with 2019-nCoV infection in Wuhan City are mainly caused by family aggregation. The clinical classification is mainly ordinary type, and the laboratory examination has no specificity. Specimens could be collected from multiple repeatable sites for 2019-nCoV nucleic acid test in suspected cases. Chest computed tomography has certain value for the diagnosis of children with 2019-nCoV infection. The recent prognosis of the patients is good with general treatment.

Anticoagulant drugs are widely used in the prevention and treatment of thromboembolic diseases. In recent years, coagulation factor Xa inhibitors have become a hot spot for the development of new anticoagulant drugs. However, the anticoagulant drugs currently used still have side-effects such as increased bleeding risk. This paper analyzes the patent applications of coagulation factor Xa inhibitors, and summarizes the development route of patent application of Bristol-Myers Squibb Company and Guangdong Dongyang Pharmaceutical Co. , Ltd. as representatives of key enterprises, in order to provide some useful references and recommendations for the development, patent protection countermeasure and intellectual property strategy of coagulation factor Xa for domestic pharmaceutical enterprises.

Nisin is an antimicrobial peptide widely used in food industry. In this study, Nisin A production in Lactococcus lactis ATCC 11454 was improved by overexpression of Nisin A structural gene nisA through introducing a shuttle expression vector pMG36ek-nisA and an integrated vector pDG780-nisA into the host strain. The differences of growth profiles and Nisin A production level between the two obtained genetic engineering strains FMM1/FMM2 and the parent strain were investigated. Our results show that while the growth profile (the growth rate, biomass and pH) of FMM1 was similar to the parent strain, its Nisin A production increased 31%. In contrast, the biomass of FMM2 was notably lower than the parent strain, while its yield of Nisin A enhanced slightly. The transcription level of genes involved in Nisin A biosynthesis in both engineering strains was further detected by RT-PCR. We found that all the 11 Nisin A biosynthetic genes in FMM1 and FMM2 had a higher transcription level than those in the parent strain, and these genes exhibited more significant increasing degree of transcription level in FMM1 which hosted the autonomous replicating nisA gene. These data suggest that expression of nisA may act as a rate-limit factor in Nisin A biosynthesis. In conclusion, this work provides a new method to improve Nisin A production by increasing the transcription level of nisA, paving the way to further large-scale industrial production of Nisin A.
Bacterial Proteins ; genetics ; Genes, Bacterial ; Genetic Engineering ; Genetic Vectors ; Lactococcus lactis ; genetics ; metabolism ; Nisin ; biosynthesis ; genetics ; Transcription, Genetic

OBJECTIVE To investigate the expression of PTEN and VEGF gene in laryngeal squamous cell carcinoma and their clinical significance. METHODS The expression of PTEN and VEGF gene were examined by using immunohistochemical S-P staining method in 10 cases of normal tissues, 20 cases of para-tumor tissues and 60 cases of LSCC. RESULTS The positive rates of PTEN in normal tissues, para-tumor tissues and LSCC were 100.0 %, 95.0 %, and 70.0 % respectively (P＜0.05),and VEGF protein showed positive expression of 20.0 %,50.0 %,73.3% in normal, para-tumor and LSCC tissues with statistical significance(P＜0.05), In LSCC, the expression of PTEN and VEGF was positively correlated with TNM stage, differentiation of tumor, cervical and distant metastasis of lymph node, 3-year survive rate of patients(P＜0.05),No significant association was observed in expression of PTEN and VEGF with tumor location,patient's age and sex(P＞0.05). Spearman correlation analysis revealed that PTEN was negatively correlated with VEGF expression(?=-0.3948, P=0.0018). CONCLUSION The aberrant expression of PTEN and VEGF may play a role in occurrence, progression and metastasis of LSCC.