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1.
Aquat Toxicol ; 270: 106896, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38490093

RESUMEN

Inorganic mercury (IHg) is hazardous to marine organisms especially resulting in neurotoxicity, bivalves are sensitive to pollutants as "ocean sentinel", but data on the neurotoxicity of IHg in bivalves are sparse. So we chosed M. chinensis philippi with typical neural structures in bivalves to investigate the neurotoxicity of IHg, which could be helpful to understand the specificity of neural regulation and the response characteristics of bivalves. After acute exposed to IHg (HgCl2) for 24 h, the metabolites of ganglion tissues in M. chinensis philippi were evaluated using 1H-nuclear magnetic resonance based metabolomics; Ca2+, neurotransmitters (nitric oxide, glutamate, acetylcholine) and related enzymes (calcineurin, nitric oxide synthase and acetylcholinesterase) were measured using biochemical detection. Compared to the control group, the levels of the nitric oxide (81.04 ± 12.84 µmol/g prot) and acetylcholine (30.93 ± 12.57 µg/mg prot) in M. chinensis philippi of IHg-treated were decreased, while glutamate (2.11 ± 0.61 mmol/L) increased significantly; the activity of nitric oxide synthase (679.34 ± 135.33 U/mg prot) was increased, while acetylcholinesterase (1.39 ± 0.44 U/mg prot) decreased significantly, and the activity of calcineurin (0.52 ± 0.02 U/mg prot) had a statistically insignificant increasing tendency. The concentration of Ca2+ (0.92 ± 0.46 mmol/g prot) in the IHg-treated group was significantly higher than that in the control group. OPLS-DA was performed to reveal the difference in metabolites between the control and IHg-challenged groups, the metabolites of glucose, glutamine, inosine, succinate, glutamate, homarine, and alanine were sensitive to IHg, subsequently metabolic pathways that were affected including glucose metabolism, glutamine metabolism, nucleotide metabolism, Krebs cycle, amino acid metabolism and osmotic regulation. In our study, IHg interfered with metabolites in M. chinensis philippi, thus the corresponding metabolic pathways were changed, which influenced the neurotransmitters subsequently. Furthermore, Ca2+overload affected the synthesis or degradation of the neurotransmitters, and then the altered neurotransmitters involved in changes in metabolic pathways again. Overall, we hypothesized that the neurotoxic effects of IHg on bivalve were in close contact with metabolism, neurotransmitters, related enzymes and Ca2+, which could be effective neurotoxic biomarkers for marine environmental quality assessment, and also provide effective data for the study of the regulatory mechanism of the nervous system in response to IHg in bivalves.


Asunto(s)
Bivalvos , Mercurio , Compuestos de Metilmercurio , Contaminantes Químicos del Agua , Animales , Mercurio/toxicidad , Mercurio/metabolismo , Acetilcolinesterasa , Óxido Nítrico , Acetilcolina , Calcineurina , Glutamina , Contaminantes Químicos del Agua/toxicidad , Bivalvos/metabolismo , Glutamatos , Neurotransmisores , Óxido Nítrico Sintasa , Compuestos de Metilmercurio/toxicidad
2.
Comput Biol Chem ; 108: 107997, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38154318

RESUMEN

This work focuses on data sampling in cancer-gene association prediction. Currently, researchers are using machine learning methods to predict genes that are more likely to produce cancer-causing mutations. To improve the performance of machine learning models, methods have been proposed, one of which is to improve the quality of the training data. Existing methods focus mainly on positive data, i.e. cancer driver genes, for screening selection. This paper proposes a low-cancer-related gene screening method based on gene network and graph theory algorithms to improve the negative samples selection. Genetic data with low cancer correlation is used as negative training samples. After experimental verification, using the negative samples screened by this method to train the cancer gene classification model can improve prediction performance. The biggest advantage of this method is that it can be easily combined with other methods that focus on enhancing the quality of positive training samples. It has been demonstrated that significant improvement is achieved by combining this method with three state-of-the-arts cancer gene prediction methods.


Asunto(s)
Redes Reguladoras de Genes , Neoplasias , Humanos , Redes Reguladoras de Genes/genética , Detección Precoz del Cáncer , Algoritmos , Aprendizaje Automático , Neoplasias/genética
3.
Trials ; 24(1): 724, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37957769

RESUMEN

BACKGROUND: Preoperative anxiety management is gaining particular attention in paediatric anaesthesia. Pharmacological and non-pharmacological resorts can be implemented to address this special issue. Despite the various approaches currently used for preoperative sedation in children, the different sedative and anti-anxiety effects between the newly marketed anaesthetic, S-ketamine, and the traditional sedative, midazolam, are still unclear. METHODS: This is a patient- and assessor-blinded randomized controlled clinical trial. Participants (n = 110) will receive S-ketamine (0.5 mg/kg) or midazolam (0.08 mg/kg) intravenously administrated at a ratio of 1:1 in the anaesthesia holding area. The primary outcome of this study is the sedative effect evaluated via the change in the modified Yale preoperative anxiety scale. It will be performed at two timepoints: in the pre-anaesthetic holding area before premedication (baseline, marked as T0) and about 5 min after premedication in the operating room without the existence of their guardians (marked as T1). Our secondary objectives include the parent separation anxiety score, postoperative agitation, caregivers' and anaesthesia care providers' satisfaction, and mask compliance. DISCUSSION: This randomized controlled trial is the first study to compare the anti-anxiety effect of intravenous S-ketamine and midazolam. We will provide a new approach for the clinical management of preoperative anxiety in preschool children posted for elective surgery. TRIAL REGISTRATION: ChiCTR2300069998. Registered on 30 March 2023.


Asunto(s)
Anestésicos , Ansiolíticos , Preescolar , Humanos , Hipnóticos y Sedantes/efectos adversos , Midazolam/efectos adversos , Ansiolíticos/efectos adversos , Método Doble Ciego , Ensayos Clínicos Controlados Aleatorios como Asunto
4.
BMJ Paediatr Open ; 7(1)2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37491133

RESUMEN

INTRODUCTION: The Nuss procedure, despite being a minimally invasive surgery, is regarded as one of the most painful surgical procedures in children, and postoperative pain control remains a major clinical issue in this population. Thoracic paravertebral nerve block (TPVB) is reported as excellent pain relief for the Nuss procedure despite its challenging performance and associated adverse effects. Serratus anterior plane block (SAPB) is a simplified and effective method for managing thoracic pain as an alternative to TPVB. However, whether SAPB can provide analgesia comparable with that provided by the TPVB approach in children undergoing the Nuss procedure is unknown. METHODS AND ANALYSIS: This will be a prospective, randomised, double-blind, single-centre, non-inferiority trial that will enrol children aged 7-16 years subjected to the Nuss operation for pectus excavatum. In total, 74 paediatric patients will be randomly assigned to either the SAPB or TPVB group after general anaesthesia to receive ultrasound-guided regional nerve blocks (0.25% ropivacaine 2.5 mg/kg). The primary outcome will be the assessment of postoperative pain intensity at predetermined time points. The secondary outcomes will include assessing intraoperative opioid intake, consumption of analgesics within 24 hours postoperatively, time of first use of rescue analgesics, extubation time, perioperative adverse events and plasma ropivacaine concentrations across the block groups. Demographic and clinical characteristics (eg, pectus severity and the number of bars used) of the patients will be recorded. All data will be collected by investigators who are blinded to the treatment. ETHICS AND DISSEMINATION: Ethical approval was obtained from the Ethics Committee on Biomedical Research of the West China Hospital of Sichuan University (2021-1275). During the period of the study, all procedures will be conducted following the principles of the Declaration of Helsinki. The results of the trial will be published in a peer-reviewed scientific journal. TRIAL REGISTRATION NUMBER: ChiCTR2200056596.


Asunto(s)
Analgesia , Bloqueo Nervioso , Niño , Humanos , Bloqueo Nervioso/efectos adversos , Bloqueo Nervioso/métodos , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/prevención & control , Dolor Postoperatorio/etiología , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto , Ropivacaína/uso terapéutico , Adolescente
5.
BMJ Paediatr Open ; 7(1)2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37316297

RESUMEN

BACKGROUND: Serratus anterior plane block (SAPB) has gained popularity in cardiothoracic surgery due to its feasibility and simplicity. However, the efficacy of ultrasound-guided single-injection SAPB in the paediatric population has not been well evaluated, as only a few studies with small sample sizes are available. METHODS: We searched PubMed, Embase (Ovid), Cochrane Central Register of Controlled Trials, Wanfang databases and China National Knowledge Infrastructure from their inception to 31 September 2022 for randomised comparative clinical trials that compared single-injection SAPB with systemic analgesia or different forms of regional analgesia in children. The primary outcomes included postoperative opioid consumption and pain scores within 24 hours. The secondary outcomes included postoperative adverse events, the need for rescue analgesia and the time from the end of surgery to endotracheal tube removal. RESULTS: Five randomised controlled trials with 418 children meeting the inclusion criteria were included. SAPB markedly reduced postoperative opioid consumption up to 24 hours compared with controls (mean difference (MD): -0.29 mg/kg, 95% CI -0.38 to -0.20, I 2 =67%]. The postoperative pain scores were reduced compared with controls: 1 hour (MD -0.6, 95% CI -1.17 to -0.04, I 2 =92%), 4-6 hours (MD -1.16, 95% CI -1.87 to -0.45, I 2 =90%) and 12 hours (MD -0.71, 95% CI -1.35 to -0.08, I 2 =86%). The incidence of postoperative nausea and vomiting was comparable between SAPB and controls. One trial suggested that the analgesic effect of SAPB was comparable to that of ICNB (intercostal nerve block). CONCLUSION: Single-injection SAPB is associated with a reduction in opioid consumption and pain intensity after cardiothoracic surgery via thoracotomy in children. Due to the high heterogeneity, the Grading of Recommendations Assessment, Development and Evaluation scores were low. Clinical trials with rigorous methodological approaches as well as safety endpoints are needed to confirm these preliminary findings. PROSPERO REGISTRATION NUMBER: CRD42021241691.


Asunto(s)
Bloqueo Nervioso , Manejo del Dolor , Dolor Postoperatorio , Procedimientos de Cirugía Plástica , Toracotomía , Niño , Humanos , Analgésicos Opioides/uso terapéutico , Manejo del Dolor/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto , Toracotomía/efectos adversos , Analgesia/métodos , Dolor Postoperatorio/prevención & control , Dolor Postoperatorio/terapia
6.
Anaesth Crit Care Pain Med ; 42(6): 101268, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37364851

RESUMEN

BACKGROUND: Postoperative analgesia in the cardiothoracic ICU has traditionally relied on intravenous opioids. Thoracic nerve blocks are attractive alternatives for analgesia that reduce the requirement for opioids, but their safety and feasibility remain unclear. METHODS: Sixty children were allocated randomly to three groups: group C received intravenous opioids alone, while group SAPB (deep serratus anterior plane block) and group ICNB (intercostal nerve block) received opioids combined with ultrasound-guided regional nerve blocks (0.2% ropivacaine 2.5 mg.kg-1) after patients were transferred to the ICU. The primary outcome was opioid requirement in the first 24 h after surgery. Other outcomes included the postoperative FLACC scale value, tracheal extubation time, and plasma ropivacaine concentrations after the block. RESULTS: The mean [sd] cumulative dose of opioids administered postoperatively within 24 h in the SAPB (168.6 [76.9] µg.kg-1) and ICNB groups (170.0 [86.8] µg.kg-1) were significantly lower by nearly 53% than those in group C (359.3 [125.3] µg.kg-1, p = 0.000). The tracheal extubation time was shorter in the regional block groups than that in the control group, but the difference was not statistically significant (p = 0.177). The FLACC scale values at 0, 1, 3, 6, 12, and 24 h post-extubation were similar in the three groups. The mean peak plasma ropivacaine concentrations in the SAP and ICNB groups were 2.1 [0.8] and 1.8 [0.7] mg.L-1, respectively, 10 min post-block and then slowly decreased. No noticeable complications associated with regional anesthesia were observed. CONCLUSIONS: Ultrasound-guided SAPB and ICNB provided safe and satisfactory early postoperative analgesia while reducing opioid consumption following sternotomy in pediatric patients. CLINICAL TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiChiCTR2100046754.


Asunto(s)
Nervios Intercostales , Bloqueo Nervioso , Humanos , Niño , Ropivacaína , Esternotomía/efectos adversos , Analgésicos Opioides/uso terapéutico , Dolor Postoperatorio/tratamiento farmacológico , Estudios Prospectivos , Estudios de Factibilidad , Ultrasonografía Intervencional , Bloqueo Nervioso/efectos adversos
7.
Microb Pathog ; 181: 106174, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37244489

RESUMEN

Exosomes are a class of extracellular vesicles released by bacteria and contain diverse biomolecules. In this study, we isolated exosomes from Vibrio harveyi and Vibrio anguillarum, which are both serious pathogens in mariculture, using a supercentrifugation method, and the proteins in the exosomes of these two vibrios were analyzed by LC-MS/MS proteomics. Exosome proteins released by V. harveyi and V. anguillarum were different; they not only contained virulence factors (such as lipase and phospholipase in V. harveyi, metalloprotease and hemolysin in V. anguillarum), but also participated in the important life activities of bacteria (such as fatty acid biosynthesis, biosynthesis of antibiotics, carbon metabolism). Subsequently, to verify whether the exosomes participated in bacterial toxicity, after Ruditapes philippinarum was challenged with V. harveyi and V. anguillarum, the corresponding genes of virulence factors from exosomes screened by proteomics were tested by quantitative real-time PCR. All the genes detected were upregulated which suggested that exosomes were involved in vibrio toxicity. The results could provide an effective proteome database for decoding the pathogenic mechanism of vibrios from the exosome perspective.


Asunto(s)
Exosomas , Vibrio , Cromatografía Liquida , Proteómica , Espectrometría de Masas en Tándem , Vibrio/genética , Factores de Virulencia/genética
8.
Front Nutr ; 9: 923590, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36034918

RESUMEN

Background: Observational studies have previously suggested a link between iron status makers and back pain. We conducted a two-sample Mendelian randomization (MR) study to determine the putative causal relationship between systemic iron status and back pain. Materials and methods: In this MR study, a genome-wide association study (GWAS) involving 48,972 individuals was used to identify genetic instruments highly associated with systemic iron status. The outcome data (back pain) were derived from the Neale Lab consortium's summary data from the UK Biobank (85,221 cases and 336,650 controls). With the inverse variance weighted (IVW) method as the main analysis, conservative analyses (selecting SNPs with concordant change of iron status biomarkers) and liberal analyses (selecting SNPs with genome-wide significant association with each iron status biomarker) were carried out. For sensitivity analyses, the MR-Egger, MR-Egger intercept, weighted median, weighted mode, and MR based on a Bayesian model averaging approaches were used. The Cochran's Q-test was used to detect heterogeneity. Results: Back pain was associated with genetically instrumented serum iron (OR = 1.01; 95% CI = 1.00-1.02, p = 0.01), ferritin (OR = 1.02; 95% CI = 1.00-1.04, p = 0.02), and transferrin saturation (OR = 1.01; 95% CI = 1.00-1.01, p = 0.01). Furthermore, there was no evidence of a link between transferrin and the risk of back pain (OR = 0.99, 95% CI = 0.98-1.00, p = 0.08). The sensitivity analyses and Cochran's Q-test indicated that no pleiotropy or heterogeneity was detected (all p > 0.05). Conclusion: We provided potential genetic evidences for the causal associations of iron status with increased incidence of back pain. However, the evidences were weakened due to the low power. Further larger MR studies or RCTs are needed to investigate small effects.

9.
J Chromatogr A ; 1678: 463365, 2022 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-35907366

RESUMEN

Penicillin G acylase (PGA), as a key enzyme, is increasingly used in the commercial production of semi-synthetic ß-lactam antibiotics (SSBAs). With the substitution of conventional chemical synthesis by emerging bioconversion processes, more and more PGAs fermented from different types of strains such as Escherichia coli (E. coli, ATCC 11105), Achromobacter sp. CCM 4824 and Providencia rettgeri (ATCC 31052) have been used in this kind of enzymatic processes. As an intermediate reaction catalyst, PGA protein and its presence in the final products may cause a potential risk of human allergic reaction and bring challenges for both quality and process controls. To achieve qualitative and quantitative analysis of PGAs and their residues in SSBAs, a tryptic digestion coupled with liquid chromatography - tandem mass spectrometry (LC-MS/MS) method was developed and proposed because of advantages like high selectivity and sensitivity. A suitable filter aided sample preparation (FASP) method was also used to remove matrix interference and to enrich the target PGA retained in the ultrafiltration membrane for an efficient enzymatic hydrolysis and subsequent accurate MS detection. Finally, twelve batches of PGAs from eight companies were identified and categorized into two types of strains (E. coli and Achromobacter sp. CCM 4824) using proteomic analysis. In total nine batches of five types of SSBAs (amoxicillin, cephalexin, cefprozil, cefdinir and cefaclor) from eight manufacturers were selected for investigation. Trace levels of PGA residual proteins ranging from 0.01 to 0.44 ppm were detected in six batches of different SSBAs which were far lower than the safety limit of 35 ppm reported by DSM, a manufacturer with expertise in the production of SSBAs by enzymatic processes. The developed FASP with LC-MS/MS method is superior to traditional protein assays in terms of selectivity, sensitivity and accuracy. Moreover, it could provide in-depth analysis of amino acid sequences and signature peptides contributing to assignment of the strain sources of PGAs. This method could become a promising and powerful tool to monitor enzymatic process robustness and reliability of this kind of SSBAs manufacturing.


Asunto(s)
Penicilina Amidasa , Humanos , Antibacterianos/metabolismo , Cromatografía Liquida , Escherichia coli/metabolismo , Penicilina Amidasa/química , Penicilina Amidasa/metabolismo , Proteómica , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem
10.
Eur Radiol ; 32(9): 5930-5942, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35384460

RESUMEN

OBJECTIVES: To develop and validate an optimal model based on the 1-mm-isotropic-3D contrast-enhanced StarVIBE MRI sequence combined with clinical risk factors for predicting survival in patients with esophageal squamous cell carcinoma (ESCC). METHODS: Patients with ESCC at our institution from 2015 to 2017 participated in this retrospective study based on prospectively acquired data, and were randomly assigned to training and validation groups at a ratio of 7:3. Random survival forest (RSF) and variable hunting methods were used to screen for radiomics features and LASSO-Cox regression analysis was used to build three models, including clinical only, radiomics only and combined clinical and radiomics models, which were evaluated by concordance index (CI) and calibration curve. Nomograms and decision curve analysis (DCA) were used to display intuitive prediction information. RESULTS: Seven radiomics features were selected from 434 patients, combined with clinical features that were statistically significant to construct the predictive models of disease-free survival (DFS) and overall survival (OS). The combined model showed the highest performance in both training and validation groups for predicting DFS ([CI], 0.714, 0.729) and OS ([CI], 0.730, 0.712). DCA showed that the net benefit of the combined model and of the clinical model is significantly greater than that of the radiomics model alone at different threshold probabilities. CONCLUSIONS: We demonstrated that a combined predictive model based on MR Rad-S and clinical risk factors had better predictive efficacy than the radiomics models alone for patients with ESCC. KEY POINTS: • Magnetic resonance-based radiomics features combined with clinical risk factors can predict survival in patients with ESCC. • The radiomics nomogram can be used clinically to predict patient recurrence, DFS, and OS. • Magnetic resonance imaging is highly reproducible in visualizing lesions and contouring the whole tumor.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Supervivencia sin Enfermedad , Neoplasias Esofágicas/diagnóstico por imagen , Carcinoma de Células Escamosas de Esófago/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Nomogramas , Estudios Retrospectivos
11.
Phytochem Anal ; 33(1): 5-11, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34275160

RESUMEN

OBJECTIVES: Because the purity of the two impurities reference standard (RS) of cefathiamidine is not easy to obtain, HPLC-PDA-ELSD were used to determin the RRFs of cefathiamidine impurities. METHODS: Peak area correction was applied to calculate RRFs to eliminate the influence of different responses caused by the difference in pH between the two mobile phases of HPLC-PDA and HPLC-PDA-ELSD. The resulting RRF values have been verified by qNMR. CONCLUSION: The new calcution method described in this article provides a reliable research idea for determintion the RRFs by HPLC-PDA-ELSD, especially when the purity of RS is unknown and the mobile phase of HPLC-PDA and HPLC-PDA-ELSD have difference. This method can be mutually verified with qNMR to ensure the accuracy of RRFs. It is also promingsing replace determination RRF by qNMR becausing economical, simple and low cost.


Asunto(s)
Luz , Cromatografía Líquida de Alta Presión , Dispersión de Radiación
12.
Front Chem ; 9: 753060, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34616716

RESUMEN

Objective: To establish a method for the determination of the chemical structure of vancomycin hydrochloride. Methods: Nuclear magnetic resonance spectroscopy and mass spectrometry were conducted to analyze the chemical structure of vancomycin hydrochloride. Results: In this study, the target compound (1) was identified as (Sα)-(3S, 6R, 7R, 22R, 23S, 26S, 36R, 38αR)-44-[[2-O-(3-amino-2, 3, 6-trideoxy-3-C-methyl-α-L-lyso-hexopyranosyl)-ß-D-glucopyranosyl] oxy]-3-(carbamoylmethyl)-10, 19-dichloro-7, 22, 28, 30, 32-pentahydroxy-6-[[(2R)-4-methyl-2-(methylamino) pentanoyl] amino]-2, 5, 24, 38, 39-pentaoxo-2, 3, 4, 5, 6, 7, 23, 24, 25, 26, 36, 37, 38, 38α-tetradecahydro-22H-8, 11: 18, 21-dietheno-23, 36-(iminomethano)-13, 16: 31, 35-dimetheno-1H, 13H-[1, 6, 9] oxadiazacyclohexadecino [4, 5-m] [10, 2, 16]-benzoxadiazacyclotetracosine-26-carboxylic acid hydrochloride. Conclusion: The method used in this study is accurate and can be used for the production and structural elucidation of vancomycin hydrochloride.

13.
Anal Biochem ; 631: 114299, 2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-34391726

RESUMEN

Antibiotics are widely used to treat bacterial infections during the process of vaccine production and storage resulting in antibiotic residues that can cause serious harm. A simple and sensitive method for residue analysis of 40 ß-lactam antibiotics was developed and validated for vaccines including inactivated enterovirus 71 vaccine (Vero cells), recombinant hepatitis B vaccine (Saccharomyces cerevisiae), and live attenuated varicella vaccine using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI- MS/MS). Samples were prepared with acetonitrile as the protein precipitant. LC separation was performed on a C18 column. These analytes were determined by LC-MS/MS operating multiple-reaction monitoring (MRM) scans in positive mode. The ranges for limits of detection (LOD) and quantification (LOQ) were as follows: 0.02-4 ng/dose (S/N ≥ 3) and 0.04-10 ng/dose in inactivated enterovirus 71 vaccine (Vero cells) and recombinant hepatitis B vaccine (Saccharomyces cerevisiae), 0.04-16 ng/dose and 0.2-20 ng/dose in live attenuated varicella vaccine. The ranges of recoveries of all antibiotics were 84.5%-108.2% in inactivated enterovirus 71 vaccine (Vero cells), 73%-108% in recombinant hepatitis B vaccine (Saccharomyces cerevisiae), and mostly 68.2%-107.8% in live attenuated varicella vaccine. This method simultaneously offers qualitative and quantitative analysis of multi-antibiotics in vaccines, which improves vaccine safety.


Asunto(s)
Antibacterianos/análisis , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Vacunas/análisis , beta-Lactamas/análisis , Animales , Vacuna contra la Varicela/análisis , Chlorocebus aethiops , Contaminación de Medicamentos , Vacunas contra Hepatitis B/análisis , Límite de Detección , Reproducibilidad de los Resultados , Saccharomyces cerevisiae , Células Vero
14.
ACS Appl Mater Interfaces ; 13(21): 24925-24936, 2021 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-34015912

RESUMEN

Ni-rich layered cathodes suffer detrimental structural changes due to irreversible phase transformation (IPT). Precisely surface structural reconstruction through foreign element doping is a potential method to alleviate IPT propagation. The structure of surface reconstructed layer is greatly determined by the foreign element content and species. Herein, small doses of Ti and Al were co-substituted in LiNi0.92Co0.08O2 to synergistically regulate the surface reductive Ni distribution, consequently constructing thin rock salt phase at the particle surface. This homogeneous rock salt phase combined with the strong Ti-O and Al-O bonds generated a reversible H2-H3 phase transition and further eliminated IPT propagation. Moreover, the suppressed IPT propagation converted the two-phase (H2 and H3) coexistence to a quasi-single-phase transition. This eliminated the strong internal strains caused by a significant lattice mismatch. The Ti and Al co-substituted LiNi0.92Co0.08O2 exhibited outstanding capacity retention and excellent structural stability. Similar improvements were observed with W or Zr and Al cosubstitution in Ni-rich layered cathodes. This study proposes a universal method for comprehensive improvement of structural stability based on the synergistic effect of dual-element cosubstitution in Ni-rich layered oxide cathodes, which is being explored for production of high-cycle-stability lithium-ion batteries.

15.
Analyst ; 146(8): 2712-2717, 2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33688885

RESUMEN

In this study, a novel colorimetric aptasensor was developed for the rapid detection and visual screening of HPV16 L1 proteins using gold nanoparticles (AuNPs) and an RNA aptamer against HPV16 L1 protein (APTHPV16 L1). The AuNP-APTHPV16 L1 conjugates could be aggregated by the addition of a salt in the presence of HPV16 L1 proteins at the ppb level. At the same time, the surface plasma resonance absorption peaks of AuNPs shifted to a short wavelength, and an observable change in color from red to blue occurred. The relative absorbance (Ablank - Asample/Ablank) at 520 nm exhibited a stable response to HPV16 L1 proteins over a concentration range from 9.6 to 201.6 ng mL-1. The visual detection limit of HPV16 L1 proteins was found to be 9.6 ng mL-1. Finally, the proposed colorimetric aptasensor was successfully applied for the rapid and effective detection of HPV16 L1 proteins in clinical samples and vaccine samples. The validity and reliability of the proposed colorimetric aptasensor were verified by the enzyme-linked immunosorbent assay method. The proposed colorimetric aptasensor provided a promising indicator for screening and quantitative detection of HPV16 L1 proteins in clinical samples.


Asunto(s)
Alphapapillomavirus , Aptámeros de Nucleótidos , Técnicas Biosensibles , Proteínas de la Cápside , Nanopartículas del Metal , Proteínas Oncogénicas Virales , Colorimetría , Oro , Papillomavirus Humano 16 , Humanos , Reproducibilidad de los Resultados
16.
Front Chem ; 8: 619307, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33585401

RESUMEN

In this study, two isomeric impurities were identified in cefotiam hydrochloride injection preparation and were characterized. Column-switching HPLC-MS and NMR techniques were used to identify the impurity 1 as the Δ3(4) isomers of cefotiam. Using software-based calculations, it was predicted that neither of the isomeric impurities was embryotoxic. This study provides a reference for the production, storage, and quality control of cefotiam and related cephalosporin antibiotics.

17.
Front Pharmacol ; 10: 1446, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31849686

RESUMEN

Traditional Chinese medicines (TCMs) represent one form of complementary and alternative medicine. The popularity and complexity in production make them attractive and vulnerable to adulteration in stages ranging from planting to production. Adulteration refers to the addition of extraneous, improper, or inferior ingredients that should not be present in TCMs. To detect and combat adulterated TCMs, supplementary testing methods (STMs), which expand the capability of routine testing standards, have been applied in China since 2003. From 2003 to 2017, a total of 184 STMs for TCMs were approved by the Chinese national drug regulatory authority. By assessing these STMs, this research intends to identify those TCMs vulnerable to adulteration, to list common adulterants, and to characterize the techniques of analysis. The results show that adulteration of TCMs can be classified into three main categories: the addition of undeclared drugs/chemical substances, substitution with non-drug components, and the addition of foreign non-drug materials. The top five therapeutic areas of TCMs vulnerable to adulteration are diabetes, calm and sleep, sexual dysfunction, pain relief, and rheumatism. A total of 166 adulterants were detected in the adulterated TCM preparations and herbal products studied here, with 158 adulterants in TCM preparations and 43 in herbal products, with 35 adulterants in common. Each STM consists of different pharmaceutical analysis techniques, including tests for physical-chemical properties, chromatography, spectroscopic techniques, and mass spectrometry. The analytical methodology of STMs relies on the combination of these techniques, with HPLC ranking the highest percentage (76.1%) and physical-chemical techniques the lowest percentage (11.4%). This research shows that STMs have played a crucial role in combating adulterated TCMs. However, STMs represent merely a product testing-centered regulatory strategy. The inspection of cultivation and manufacturing processes should also be strengthened. More importantly, the awareness and self-discipline of TCM manufacturers in implementing good manufacturing practices and regulating the planting and cultivation of raw materials should be improved.

18.
J Chromatogr A ; 1608: 460418, 2019 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-31420179

RESUMEN

High performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (HPLC-QTOF-MS) is widely used to qualitatively characterize the chemical profiles of herbal medicines, in which the generated adducts and fragments are crucial for confirming molecular ion (deprotonated/protonated ion) and deducing structure of detected components. However, how chromatographic and mass spectrometric (LC-MS) conditions/parameters affect the quantity and intensity of adducts and fragments of detected components is scarcely concerned. In present study, three types of triterpene saponins from the root of Ilex asprella (RIA) were selected as a case study to systematically investigate the effects of LC/MS conditions/parameters on their ionization and fragmentation, so as to obtain higher intensity (higher detection sensitivity) and quantity (rich information) of adducts and fragments for the characterization of components in RIA. It was found that for LC conditions, methanol as organic phase was more benefit for generating more adducts with higher intensity; formic acid as a modifier suppressed the formation of [M-2H]2-, thus promoted the generation of other types of adducts at lower concentration but inhibited the generation when the concentration exceeded 0.1%. MS parameters affect scarcely the quantity but mainly intensity of adducts, cone voltage, source temperature and desolvation gas flow have relatively higher impacts when compared with other parameters. Collision energy affected both quantity and intensity of fragments. MS parameters at the medium value largely increased the quantity and intensity of adducts and fragments. Three-types of triterpene saponins presented structurally specific ionization and fragmentation due to their amounts of acidic substitutes. A total of 55 components were detected and definitely or tentatively identified in RIA under the optimized LC-MS conditions, among which 35 triterpene saponins were firstly discovered. This is the first report that proposes and validates a systematic approach for assessing the effects of LC/MS conditions/parameters on the ionization and fragmentation of analytes, which could be helpful for the optimization of LC-MS conditions for effective chemical profiling analysis of herbal medicines.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Ilex/química , Extractos Vegetales/química , Saponinas/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Triterpenos/química , Estructura Molecular , Plantas Medicinales/química
19.
J Chromatogr A ; 1581-1582: 33-42, 2018 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-30389211

RESUMEN

In this study, a time segment scanning-based quasi-multiple reaction monitoring (quasi-MRM) mode was proposed to improve the quantitative performance of UPLC-QTOF-MS/MS. To achieve the quasi-MRM mode, a strategy to select the ion pair (precursor and product ions) of each analyte was adopted as follows. First, a stable and abundant ion by quadrupole was set as precursor ion in MS scan mode. Second, the fragment ions of the precursor ion formed via collision-induced dissociation were measured by time-of-flight (TOF) in MS/MS scan mode; a characteristic, stable and abundant fragment ion (or precursor ion in case of fragment ion unavailable) was designated as the product ion. Third, the detection specificity and sensitivity of the product ion by TOF were strengthened through time segment scanning over a narrowed mass scan range. The proposed quasi-MRM mode achieved simultaneous quantification of fifteen major components in Moutan Cortex, a widely used medicinal herb, as well as its sulfur-fumigated samples. The quasi-MRM mode was methodologically compared with the other two quantitative modes commonly used in the UPLC-PDA-QTOF-MS/MS apparatus, namely UPLC-PDA and extracted ion analysis. The results demonstrated that the quasi-MRM mode performed better in specificity, sensitivity and linearity. The quasi-MRM mode was further validated with regard to precision, accuracy and stability. The research deliverables indicate that the proposed mode improved the quantitative capability of UPLC-QTOF-MS/MS, and therefore could serve as a potential mode for QTOF-MS/MS-based quantification of herbal medicines.


Asunto(s)
Técnicas de Química Analítica/métodos , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos/química , Medicina de Hierbas , Paeonia/química , Espectrometría de Masas en Tándem , Plantas Medicinales/química
20.
Molecules ; 23(8)2018 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-30115851

RESUMEN

Gene fusion structure is a class of common somatic mutational events in cancer genomes, which are often formed by chromosomal mutations. Identifying the driver gene(s) in a fusion structure is important for many downstream analyses and it contributes to clinical practices. Existing computational approaches have prioritized the importance of oncogenes by incorporating prior knowledge from gene networks. However, different methods sometimes suffer different weaknesses when handling gene fusion data due to multiple issues such as fusion gene representation, network integration, and the effectiveness of the evaluation algorithms. In this paper, Synstable Fusion (SYN), an algorithm for computationally evaluating the fusion genes, is proposed. This algorithm uses network-based strategy by incorporating gene networks as prior information, but estimates the driver genes according to the destructiveness hypothesis. This hypothesis balances the two popular evaluation strategies in the existing studies, thereby providing more comprehensive results. A machine learning framework is introduced to integrate multiple networks and further solve the conflicting results from different networks. In addition, a synchronous stability model is established to reduce the computational complexity of the evaluation algorithm. To evaluate the proposed algorithm, we conduct a series of experiments on both artificial and real datasets. The results demonstrate that the proposed algorithm performs well on different configurations and is robust when altering the internal parameter settings.


Asunto(s)
Algoritmos , Fusión de Oncogenes , Redes Reguladoras de Genes , Humanos , Modelos Genéticos , Mutación , Neoplasias/genética
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