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1.
Anal Chem ; 96(18): 7179-7186, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38661266

RESUMEN

This study uses real-time monitoring, at microsecond time scales, with a charge-sensing particle detector to investigate the evaporation and fission processes of methanol/micrometer-sized polystyrene beads (PS beads) droplets and bacterial particles droplets generated via electrospray ionization (ESI) under elevated temperatures. By incrementally raising capillary temperatures, the solvent, such as methanol on 0.75 µm PS beads, experiences partial evaporation. Further temperature increase induces fission, and methanol molecules continue to evaporate until PS ions are detected after this range. Similar partial evaporation is observed on 3 µm PS beads. However, the shorter period of the fission temperature range is necessary compared to 0.75 µm PS beads. For the spherical-shaped bacterium, Staphylococcus aureus, the desolvation process shows a similar fission period as compared to 0.75 µm PS beads. Comparably, the rod-shaped bacteria, Escherichia coli EC11303, and E. coli strain W have shorter fission periods than S. aureus. This research provides insights into the evaporation and fission mechanisms of ESI droplets containing different sizes and shapes of micrometer-sized particles, contributing to a better understanding of gaseous macroion formation.


Asunto(s)
Escherichia coli , Poliestirenos , Espectrometría de Masa por Ionización de Electrospray , Staphylococcus aureus , Poliestirenos/química , Escherichia coli/química , Tamaño de la Partícula , Temperatura , Volatilización , Metanol/química , Microesferas
2.
J Sci Food Agric ; 103(4): 2014-2022, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36221181

RESUMEN

BACKGROUND: Tartary buckwheat is rich in flavonoids. The application of physical processing technology and exogenous materials treatment can effectively promote grain germination and the accumulation of bioactive secondary metabolites. The content of four flavonoids, the activities of key enzymes (phenylalanine ammonia-lyase (PAL), chalcone isomerase (CHI), flavonol synthase (FLS)) and the expression of key enzyme genes (FtPAL, FtCHI, FtFLS1, FtFLS2) in Tartary buckwheat sprouts treated with microwave and l-phenylalanine (l-Phe) were investigated, and the relationship between them was analyzed to explore the mechanism of promoting flavonoid accumulation, and to provide a theoretical basis for the development of functional Tartary buckwheat sprout food. RESULTS: Germination can promote the synthesis of flavonoids. The contents of chlorogenic acid and rutin in 7-day sprouts increased by 13 420.63% and 225.12% compared with seeds, respectively. Under the best treatment condition T3 (microwave 250 W, 90 s, 2.9 mmol L-1 L-Phe), the specific activities of PAL, CHI and FLS in 5-day-old sprouts increased by 47.84%, 53.04% and 28.02% compared with control check (CK), respectively; and the expression of FtPAL, FtCHI and FtFlS1 increased by 39.84%, 24.78% and 33.72% compared with CK, respectively. Correlation analysis showed that the content of flavonoids in Tartary buckwheat sprouts was significantly positively correlated with the specific activities of key enzymes (P < 0.01) and dynamically correlated with genes related to the synthesis of three enzymes. CONCLUSION: It suggested that microwave and l-Phe treatment may promote the synthesis of flavonoids by promoting the expression of key enzymes genes in phenylpropane metabolism and controlling the activity of key enzymes in phenylpropane metabolism. © 2022 Society of Chemical Industry.


Asunto(s)
Fagopyrum , Flavonoides , Flavonoides/metabolismo , Fagopyrum/química , Fenilalanina , Microondas , Rutina , Fenilanina Amoníaco-Liasa/genética , Fenilanina Amoníaco-Liasa/metabolismo
3.
Anal Chem ; 94(34): 11734-11738, 2022 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-35977070

RESUMEN

Polyhydroxyalkanoate (PHA) is one of the biocompatible and biodegradable plastics that can be produced and accumulated as granules inside microorganisms. In this study, a new approach to rapidly quantify a short-chain-length PHA, polyhydroxybutyrate (PHB), produced from genetically engineered Escherichia coli containing phaCAB is presented. The mass of each bacterial cell was measured using a laser-induced radio frequency (rf) plasma charge detection quadrupole ion trap mass spectrometer (LIRFP CD QIT-MS), and then, the PHB contents were determined by calculating the change in cellular mass. The quantitative results showed that the PHB contents measured by LIRFP CD QIT-MS were consistent with those by reference analysis, gas chromatography (GC). The PHB content of each bacterial sample can be obtained within 20 min from sampling using LIRFP CD QIT-MS while GC analysis takes 2 days. In addition, LIRFP CD QIT-MS does not use any hazardous chemicals in cellular mass quantification as compared to GC. This indicates that LIRFP CD QIT-MS has potential in routine monitoring of PHB production.


Asunto(s)
Escherichia coli , Polímeros , Cromatografía de Gases y Espectrometría de Masas , Hidroxibutiratos , Espectrometría de Masas/métodos , Poliésteres
4.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(12): 1419-1424, 2020 Dec 28.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-33472997

RESUMEN

OBJECTIVES: Bispectral index (BIS) can reflect the depth of propofol sedation. This study aims to compare the anesthetic satisfaction, anesthetic dose, and hemodynamic changes between closed-loop target controlled infusion (CLTCI) and open-loop target controlled infusion (OLTCI) during abdominal surgery. METHODS: From December 2016 to December 2018, 70 patients undergoing abdominal surgery under general anesthesia were selected in Beijing Hospital, including 51 males and 19 females, at the age from 49 to 65 years old. They were classified as grade I-II by the American Society of anesthesiologists (ASA) and were randomly divided into the CLTCI group and the OLTCI group (n=35). The CLTCI group received propofol CLTCI, and the target BIS value was set between 45 to 55; in the OLTCI group, the plasma target concentration was adjusted to maintain the BIS value between 40 to 60. Both groups were given remifentanil by target controlled infusion, and the plasma target concentration was 6.0 ng/mL. The percentages of adequate anesthesia time, deep anesthesia time, and light anesthesia time were calculated. The total induction dose of propofol, continuous infusion dose of propofol, predicted target propofol concentration of effect chamber, and continuous infusion dose of remifentanil were calculated. The times of automatic adjustment of propofol concentration in closed-loop system and manual adjustment of propofol concentration in the OLTCI group were recorded. Hemodynamic indexes were recorded, and the percentage of target mean arterial pressure (MAP) maintenance time and target heart rate (HR) maintenance time were calculated. Anesthesia time, operation time, recovery time, and extubation time were compared between the 2 groups. RESULTS: In the induction stage, the percentage of adequate anesthesia time in the CLTCI group was higher than that in the OLTCI group, and the percentage of deep anesthesia time in the CLTCI group was significantly lower than that in the OLTCI group (both P<0.05). In the maintenance stage, the percentage of light anesthesia time in the CLTCI group was significantly lower than that in the OLTCI group (P<0.05). The times of propofol adjustment in the CLTCI group was significantly more than that in the OLTCI group (P<0.001). The total induction dose of propofol in the CLTCI group was less than that in the OLTCI group (P<0.05), but there were no significant differences in the continuous infusion dose of propofol, predicted target concentration of propofol, continuous infusion dose of remifentanil between the 2 groups (all P>0.05). There were no significant differences in the percentages of target MAP maintenance time and target HR maintenance time between the 2 groups (both P>0.05). There was no intraoperative awareness in both groups, and there were no significant differences in operation time and anesthesia time between the 2 groups (both P>0.05). CONCLUSIONS: Compared with propofol OLTCI, anesthesia with propofol CLTCI under BIS guidance can maintain a more appropriate depth of anesthesia sedation and more stable hemodynamics.


Asunto(s)
Anestesia General , Propofol , Procedimientos Quirúrgicos Operativos , Abdomen/cirugía , Anciano , Anestesia Intravenosa , Anestésicos Intravenosos , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Remifentanilo
5.
Anal Chem ; 90(22): 13236-13242, 2018 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-30352503

RESUMEN

A laser-induced rf plasma (LIRFP) ion source was developed to ionize submicrometer-sized particles for the first time. The LIRFP ion source can increase the charge of those particles to several thousand charges via charge exchange reactions so that those particles can be trapped and analyzed with a charge detection quadrupole ion trap-mass spectrometer (CD QIT-MS). Different reagent gases for charge exchange reaction were investigated, viz. argon, nitrogen, oxygen, methane, helium, krypton, xenon, argon/methane (with ratios of 10:1 and 2:1), argon/nitrogen (with a ratio of 1:1), nitrogen/oxygen (10:1), krypton/methane (10:1), and air. The average charge of 0.75 µm polystyrene particles could reach 1631 using an argon/methane mixture with a ratio of ∼10:1. The average charges for freeze-dried Escherichia coli EC11303, Escherichia coli strain W, and Staphylococcus aureus were 842, 1112, and 971, respectively, with a mass-to-charge ratio ( m/ z) range from 107 to 108; and the average masses were 3.5 × 1010 Da, 6.0 × 1010 Da, and 5.6 × 1010 Da, respectively. The average mass and charge of the vaccinia virus were ∼9.1 × 109 Da and ∼708 with a m/ z of ∼107. This LIRFP CD QIT-MS method was rapid with only 20 min for each sample measurement.


Asunto(s)
Gases/química , Iones/química , Escherichia coli/química , Rayos Láser , Espectrometría de Masas/instrumentación , Espectrometría de Masas/métodos , Tamaño de la Partícula , Poliestirenos/química , Ondas de Radio , Staphylococcus aureus/química , Electricidad Estática , Virus Vaccinia/química
6.
BMC Anesthesiol ; 18(1): 148, 2018 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-30342470

RESUMEN

BACKGROUND: Many cases of coronary artery spasm (CAS) during general plus epidural anesthesia have been reported. But transversus abdominis plane(TAP) block in combination with general anesthesia has not been reported to be a cause of CAS, let alone a life-threatening CAS. CASE PRESENTATION: In this case report, we present a case of a patient with CAS accompanied by ventricular fibrillation under general anesthesia with TAP block. CONCLUSION: Coronary artery spasm, even life-threatening CAS, may occur during TAP block in combination with general anesthesia.


Asunto(s)
Anestesia General/efectos adversos , Vasoespasmo Coronario/inducido químicamente , Bloqueo Nervioso/efectos adversos , Fibrilación Ventricular/inducido químicamente , Músculos Abdominales/inervación , Adulto , Anestesia General/métodos , Humanos , Masculino , Bloqueo Nervioso/métodos
7.
Aging Clin Exp Res ; 30(10): 1217-1223, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29435832

RESUMEN

BACKGROUND: The development of sensitive myocardial-specific cardiac biomarkers allows for detection of very small amounts of myocardial injury or necrosis. Myocardial injury (MI) as a prelude of the serious perioperative complication myocardial infarction, should be paid more attention, especially in elderly susceptible patients. Myocardial injury after abdominal surgery in elderly patients has not been described yet. The objectives of this study were to identify the incidence, predictors, characteristics and the impact of MI on outcome in elderly patients underwent abdominal surgery. METHODS: Patients aged ≥ 65 who underwent abdominal surgery longer than 2 h between January 2016 and March 2017 were reviewed. Patients with peak troponin I level of 0.04 ng/ml or greater (abnormal laboratory threshold) within once-administration-period and without non-ischemia troponin elevation proof (e.g., sepsis) were assessed for characteristics and prognosis. Risk factors of MI were determined by multivariable regression. RESULTS: Among 285 patients with whole information, 36 patients (12.6%) suffered MI, only 2 patients (0.7%) fulfilled definition of myocardial infarction. With most of them occurred within first 7 days after surgery. Multivariable analysis showed that coronary artery disease (CAD) history [odds ratio (OR) 2.817, P = 0.015], non-laparoscopic surgery (OR 5.181, P = 0.030), blood loss ≥ 800 ml (OR 3.430, P = 0.008), non-venous maintain (OR 2.105, P = 0.047), and infection (OR 4.887, P = 0.008) as risk factors for MI. MI was associated with longer hospital stay (P = 0.006), more cardiac consultation (P = 0.011), higher infection(P = 0.016) and reoperation(P = 0.026) rate. CONCLUSION: MI is common in elderly patients who underwent abdominal surgery, while myocardial infarction is infrequent. They are both associated with risk factors and worse prognosis. MI deserves more attention especially in elderly patients. Troponin I measurement is a useful test after massive surgery, which can help risk-stratifying patients, effective preventing, prompt managing and predicting outcomes. Routine monitoring of cardiac biomarkers especially within 7 days after abdominal surgery in elderly patients is recommended.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Infarto del Miocardio/etiología , Complicaciones Posoperatorias/etiología , Anciano , Biomarcadores/sangre , Enfermedad de la Arteria Coronaria , Femenino , Humanos , Incidencia , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Tempo Operativo , Factores de Riesgo , Troponina/sangre
8.
J Anesth ; 31(1): 58-65, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-26350110

RESUMEN

BACKGROUND: Transcutaneous electrical acupoint stimulation (TEAS), a non-invasive and non-pharmacological adjunctive intervention for perioperative analgesia, may also reduce the incidence of postoperative pulmonary complications. The effect of TEAS on video-assisted thoracic surgical (VATS) patients is still unknown, however. The purpose of this study was to investigate the effects of TEAS of different frequency on perioperative anesthetic dosage, recovery, complications, and prognosis for patients undergoing VATS lobectomy. METHODS: Eighty VATS lobectomy patients with no previous experience of TEAS or acupuncture were randomly assigned to four groups: control (con), 2/100, 2, and 100 Hz. The last three experimental groups received TEAS at the indicated frequencies for 30 min before induction, during the operation, and for another 30 min 24 and 48 h after surgery. 2/100 Hz is a type of alternating frequency which goes between 2 and 100 Hz every 3 s. TEAS was administered over acupoints Neiguan, Hegu, Lieque, and Quchi on the sick lateral. Electrodes were applied to the patients in the control group, but no TEAS was used. Anesthetic dosage, blood gas analysis results, lung function indexes FEV1 and FVC, post-anesthesia care unit (PACU) status, postoperative complications, and quality of life scores were recorded and analyzed statistically. RESULTS: Intraoperative opioid consumption was lowest in the 2/100 Hz group, with statistical significance (con, P ≤ 0.001; 2 Hz, P ≤ 0.001; 100 Hz, P = 0.026). Compared with preoperative FEV1 and FVC, postoperative FEV1 and FVC were significantly lower in all groups; during one-lung ventilation, arterial oxygen partial pressure (PaO2) decreased more slowly in the 2/100 Hz group than in the con group (P = 0.042). Moreover, in the 2/100 Hz group extubation time was shorter (P = 0.038), visual analgesia scale score lower (P = 0.047), and duration of PACU stay shorter (P = 0.043) than in the con group. In the 100 Hz group incidence of postoperative nausea and vomiting (PONV) was lower than the con group (P = 0.044). In all groups mean postoperative physical component scores were significantly lower than mean preoperative scores. CONCLUSIONS: TEAS is a safe noninvasive adjunctive intervention for anesthesia management among patients undergoing VATS lobectomy. TEAS at 2/100 Hz can reduce intraoperative opioid dosage and slow the decrease of PaO2 during one-lung ventilation. It can also effectively reduce pain score, extubation time, and PACU stay immediately after surgery. Further, 100 Hz TEAS can reduce PONV morbidity.


Asunto(s)
Puntos de Acupuntura , Anestésicos/administración & dosificación , Anestésicos/efectos adversos , Pulmón/cirugía , Cirugía Torácica Asistida por Video/métodos , Estimulación Eléctrica Transcutánea del Nervio/métodos , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/uso terapéutico , Periodo de Recuperación de la Anestesia , Cuidados Críticos , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor Postoperatorio/epidemiología , Periodo Perioperatorio , Pronóstico , Pruebas de Función Respiratoria
9.
Anal Chem ; 88(23): 11913-11918, 2016 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-27780355

RESUMEN

Mass is a fundamental physical property of an individual cell, from which is revealed the cell growth, cycle, and activity. Taking advantage of cell mass spectrometry (CMS), accurate mass measurement of a charged single cell has been achieved. However, with the increasing demand for high-efficiency single-cell analysis in biology, the limited throughput and inefficient cell desorption/ionization of the CMS inevitably become important issues. To address the challenge, a state of the art visible-wavelength matrix assisted laser desorption/ionization (MALDI) CMS was developed. The employed transmission mode laser ablation and fast evaporation sample preparation enabled the visible-wavelength MALDI to be soft enough and to generate intact charged cells for mass measurement. By using resorufin as matrix, ten sorts of cells, viz., red blood cells (RBCs), Jurkat (JK), CCRF-CEM, SNU-5, BGC-803, MCF-7, L-O2, 293T, Hep G2, and A549 cells, have been successfully analyzed. It was found that the desorption/ionization efficiency of visible-wavelength MALDI was at least 3-fold higher than that of conventional laser-induced acoustic desorption (LIAD) and relevant to the suspension/adherent property of analyzed cells. Based on the measured mass, different cell types in either the individual or mixed state can be differentiated successfully.


Asunto(s)
Análisis de la Célula Individual , Línea Celular , Humanos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrofotometría Ultravioleta
10.
Anal Chem ; 86(8): 3876-81, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24650149

RESUMEN

In this paper, particle mass spectrometry (PMS), which consists of an aerodynamic desorption/ionization (AD) source, a quadrupole ion trap (QIT) mass analyzer, and a charge detector, was exploited to characterize the protein adsorption on microparticles based on the mass variations of microparticles before and after protein adsorption. This method is simple and has low sample cost. Importantly, its mass resolution is good enough to distinguish the microparticles with and without protein. For the adsorption of bovine serum albumin (BSA) on 3 µm porous poly styrene-divinylbenzene (poly S-DVB), the minimum mass increase that can be resolved by PMS corresponds to 128 fg (1.8 ng/cm(2)) or 1.17 × 10(6) BSA molecules on each poly S-DVB particle. With PMS, the adsorption process of BSA on poly S-DVB spheres was successfully characterized, and the obtained maximum adsorption capacity qm and dissociation constant Kd were consistent with that determined by the conventional depletion method. In addition, the influence of surface modification of silica particles on the enzyme immobilization was evaluated. Compared with C4 (propyldimethylsilane), C8 (octyldimethylsilane), and Ph (phenyldimethylchlorosilane), the CN (cyanoethyldimethylchlorosilane) functionalized silica particles were screened to be most beneficial for the immobilization of both lysozyme and trypsin.


Asunto(s)
Nanopartículas/química , Proteínas/química , Adsorción , Calibración , Enzimas Inmovilizadas/química , Concentración de Iones de Hidrógeno , Espectrometría de Masas , Muramidasa/química , Tamaño de la Partícula , Albúmina Sérica Bovina/química , Dióxido de Silicio , Tripsina/química
11.
Analyst ; 139(14): 3507-23, 2014 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-24878969

RESUMEN

Large biomolecules and bioparticles play a vital role in biology, chemistry, biomedical science and physics. Mass is a critical parameter for the characterization of large biomolecules and bioparticles. To achieve mass analysis, choosing a suitable ion source is the first step and the instruments for detecting ions, mass analyzers and detectors should also be considered. Abundant mass spectrometric techniques have been proposed to determine the masses of large biomolecules and bioparticles and these techniques can be divided into two categories. The first category measures the mass (or size) of intact particles, including single particle quadrupole ion trap mass spectrometry, cell mass spectrometry, charge detection mass spectrometry and differential mobility mass analysis; the second category aims to measure the mass and tandem mass of biomolecular ions, including quadrupole ion trap mass spectrometry, time-of-flight mass spectrometry, quadrupole orthogonal time-of-flight mass spectrometry and orbitrap mass spectrometry. Moreover, algorithms for the mass and stoichiometry assignment of electrospray mass spectra are developed to obtain accurate structure information and subunit combinations.


Asunto(s)
Espectrometría de Masas/instrumentación , Espectrometría de Masas/métodos , Algoritmos , Animales , Cápside/química , Diseño de Equipo , Humanos , Peso Molecular , Subunidades de Proteína/química , Proteínas/química , Motor de Búsqueda , Virus/química
12.
J Mater Chem B ; 12(14): 3533-3542, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38526339

RESUMEN

Fluorescent nanodiamonds (FNDs) are carbon nanoparticles containing a dense ensemble of nitrogen-vacancy defects as color centers. These centers have exceptional photostability and unique quantum properties, making them useful for ultrasensitive biosensing applications. This work employed FNDs conjugated with antibodies as magneto-optical immunosensors for tuberculosis (TB) diagnostics using competitive spin-enhanced lateral flow immunoassay (SELFIA). ESAT6 (6-kDa early secretory antigenic target) of Mycobacterium tuberculosis is a clinical marker of TB. We evaluated the assay's performance using the recombinant ESAT6 antigen and its antibodies noncovalently coated on FNDs. A detection limit of ∼0.02 ng mL-1 was achieved with the lateral flow membrane strip pre-structured with a narrow channel of 1 mm width. Adopting a cut-off value of 24.0 ng mm-1 for 100-nm FNDs on the strips, the method detected 49 out of 50 clinical samples with Mycobacterium tuberculosis complexes. In contrast, none of the assays for 10 clinical samples with non-tuberculous mycobacteria (NTM) isolates exhibited the presence of ESAT6. These results suggest that the SELFIA platform is applicable for TB detection and can differentiate TB from NTM infections, which also affect the human respiratory system. The FND-enabled immunosensing techniques are versatile and promising for early detection of TB and other diseases, opening a new avenue for biomedical applications of carbon-based nanomaterials.


Asunto(s)
Técnicas Biosensibles , Mycobacterium tuberculosis , Nanodiamantes , Tuberculosis , Humanos , Inmunoensayo , Tuberculosis/diagnóstico , Colorantes , Anticuerpos
13.
Anal Methods ; 16(22): 3464-3474, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38804556

RESUMEN

The unambiguous identification of protein species requires high sequence coverage. In this study, we successfully improved the sequence coverage of early secretory 10 kDa cell filtrate protein (CFP-10) and 6 kDa early secretory antigenic target (ESAT-6) proteins from the Mycobacterium tuberculosis complex (MTC) in broth culture media with the use of the 4-chloro-α-cyanocinnamic acid (Cl-CCA) matrix. Conventional matrices, α-cyano-hydroxy-cinnamic acid (CHCA) and 2,5-dihydroxybenzoic acid (DHB), were also used for comparison. After nanodiamond (ND) extraction, the sequence coverage of the CFP-10 protein was 87% when CHCA and DHB matrices were used, and the ESAT-6 protein was not detected. On the other hand, the sequence coverage for ND-extracted CFP-10 and ESAT-6 could reach 94% and 100%, respectively, when the Cl-CCA matrix was used and with the removal of interference from bovine serum albumin (BSA) protein and α-crystallin (ACR) protein. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) was also adopted to analyze the protein mass spectra. A total of 6 prominent ion signals were observed, including ESAT-6 protein peaks at mass-to-charge ratios (m/z) of ∼7931, ∼7974, ∼9768, and ∼9813 and CFP-10 protein peaks at m/z of ∼10 100 and ∼10 660. The ESAT-6 ion signals were always detected concurrently with CFP-10 ion signals, but CFP-10 ion signals could be detected alone without the ESAT-6 ion signals. Furthermore, the newly found ESAT-6 peaks were also confirmed using a Mag-Beads-Protein G kit with an ESAT-6 antibody to capture the ESAT-6 protein, which was also consistent with the sequence coverage analysis.


Asunto(s)
Antígenos Bacterianos , Proteínas Bacterianas , Mycobacterium tuberculosis , Nanodiamantes , Mycobacterium tuberculosis/química , Proteínas Bacterianas/química , Nanodiamantes/química , Antígenos Bacterianos/química , Antígenos Bacterianos/aislamiento & purificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
14.
Anal Chem ; 85(9): 4370-5, 2013 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-23534443

RESUMEN

An ambient desorption/ionization method, named aerodynamic desorption (AD), was proposed for the in situ rapid mass measurement of microparticles. The AD method exploited the discontinuous atmospheric pressure interface (DAPI) to generate a pulsed airflow, which was used to desorb the microparticles under atmospheric pressure. Various microparticles, e.g., bacteria, cell, polystyrene, synthetic diamond, and silica particles, with different size and surface component were successfully desorbed. Similar to that in the conventional laser-induced acoustic desorption (LIAD) method, these microparticles were desorbed as precharged ions in the AD process and the charge number was largely relevant to the particle size. However, compared with LIAD, the sensitivity of the AD method was higher. A lower concentration of particles was required for the analysis. In addition, the construction and sampling process of AD source were much simpler. All types of liquid, solid, or/and gaseous samples can be directly sampled under ambient condition. As a demonstration of this AD method, the in situ mass analysis of red blood cells (RBCs) and E. coli bacteria were carried out using a homemade ambient AD mass spectrometer consisting of AD source, QIT mass analyzer, and charge detector. Their mass and mass distributions were obtained successfully.


Asunto(s)
Diamante/análisis , Eritrocitos/química , Escherichia coli/química , Poliestirenos/análisis , Dióxido de Silicio/análisis , Presión Atmosférica , Tamaño de la Partícula , Propiedades de Superficie
15.
Anal Chem ; 85(23): 11275-83, 2013 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-24171642

RESUMEN

Electrospray ionization coupled to native mass spectrometry (MS) has evolved into an important tool in structural biology to decipher the composition of protein complexes. However, the mass analysis of heterogeneous protein assemblies is hampered because of their overlapping charge state distributions, fine structure, and peak broadening. To facilitate the mass analysis, it is of importance to automate preprocessing raw mass spectra, assigning ion series to peaks and deciphering the subunit compositions. So far, the automation of preprocessing raw mass spectra has not been accomplished; Massign was introduced to simplify data analysis and decipher the subunit compositions. In this study, we develop a search engine, AutoMass, to automatically assign ion series to peaks without any additional user input, for example, limited ranges of charge states or ion mass. AutoMass includes an ion intensity-dependent method to check for Gaussian distributions of ion series and an ion intensity-independent method to address highly overlapping and non-Gaussian distributions. The minimax theorem from game theory is adopted to define the boundaries. With AutoMass, the boundaries of ion series in the well-resolved tandem mass spectra of the hepatitis B virus (HBV) capsids and those of the mass spectrum from CRISPR-related cascade protein complex are accurately assigned. Theoretical and experimental HBV ion masses are shown in agreement up to ~0.03%. The analysis is finished within a minute on a regular workstation. Moreover, less well-resolved mass spectra, for example, complicated multimer mass spectra and norovirus capsid mass spectra at different levels of desolvation, are analyzed. In sum, this first-ever fully automatic program reveals the boundaries of overlapping ion peak series and can further aid developing high-throughput native MS and top-down proteomics.


Asunto(s)
Automatización de Laboratorios/métodos , Teoría del Juego , Motor de Búsqueda/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos , Algoritmos , Espectrometría de Masas/métodos
16.
Front Nutr ; 10: 1168361, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37476405

RESUMEN

Compared with the common grain, Tartary buckwheat enjoys higher nutritional value. Some distinctive nutrition associated with physiological activity of Tartary buckwheat is valuable in medicine. In addition, it's a good feed crop. In the paper, the main components (starch, protein, amino acid, fatty acid and mineral) and polyphenol bioactive components in Tartary buckwheat and its sprouts were reviewed, and the accumulation of flavonoids in sprouts during germination, especially the methods, synthetic pathways and mechanisms of flavonoid accumulation was summarized. The research on bioactive components and health benefits of Tartary buckwheat also were reviewed. Besides, the applications of innovative physical technology including microwave, magnetic, electromagnetic, ultrasonic, and light were also mentioned and highlighted, which could promote the enrichment of some active substances during seeds germination and growth of Tartary buckwheat sprouts. It would give a good support and benefit for the research and processing of Tartary buckwheat and its sprouts in next day.

17.
Food Sci Biotechnol ; 32(1): 11-19, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36606090

RESUMEN

The phenolic substances, antioxidant capacity, and enzyme inhibitory activity of germinated Fagopyrum tataricum (Tartary buckwheat) under different microwave and l-phenylalanine (l-Phe) were investigated for the potential of enriching polyphenols. With the germination of seeds, the contents of total phenolics and total flavonoids increased, the antioxidant capacity and enzyme inhibitory activity were enhanced. The highest contents of total phenolics and total flavonoids in Tartary buckwheat sprouts were 17.41 mg GAE/g and 6.26 g RE/100 g DW (7 days), respectively. Correlation analysis and principal component analysis indicated that T3 (microwave 250 W, 90 s; l-Phe 2.9 mmol/L) could effectively improve the content of polyphenols, enzyme inhibition activity and antioxidant capacity of Tartary buckwheat sprouts obviously. This study hopes to provide some new ideas for enriching phenolics and improving antioxidation of Tartary buckwheat sprouts.

18.
Heliyon ; 9(10): e20796, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37842612

RESUMEN

A highly accurate classification of diabetes mellitus (DM) with the synthetic impacts of several variables is first studied via optoacoustic technology in this work. For this purpose, an optoacoustic measurement apparatus of blood glucose is built, and the optoacoustic signals and peak-peak values for 625 cases of in vitro rabbit blood are obtained. The results show that although the single impact of five variables are obtained, the precise classification of DM is limited because of the synthetic impacts. Based on clinical standards, different levels of blood glucose corresponding to hypoglycaemia, normal, slight diabetes, moderate diabetes and severe diabetes are employed. Then, a wavelet neural network (WNN) is utilized to establish a classification model of DM severity. The classification accuracy is 94.4 % for the testing blood samples. To enhance the classification accuracy, particle swarm optimization (PSO) and quantum-behaved particle swarm optimization (QPSO) are successively utilized to optimize WNN, and accuracy is enhanced to 98.4 % and 100 %, respectively. It is demonstrated from comparison between several algorithms that optoacoustic technology united with the QPSO-optimized WNN algorithm can achieve precise classification of DM with synthetic impacts.

19.
Foods ; 12(10)2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37238810

RESUMEN

Exploring a cost-effective and high-accuracy optical detection method is of great significance in promoting fruit quality evaluation and grading sales. Apples are one of the most widely economic fruits, and a qualitative and quantitative assessment of apple quality based on soluble solid content (SSC) was investigated via visible (Vis) spectroscopy in this study. Six pretreatment methods and principal component analysis (PCA) were utilized to enhance the collected spectra. The qualitative assessment of apple SSC was performed using a back-propagation neural network (BPNN) combined with second-order derivative (SD) and Savitzky-Golay (SG) smoothing. The SD-SG-PCA-BPNN model's classification accuracy was 87.88%. To improve accuracy and convergence speed, a dynamic learning rate nonlinear decay (DLRND) strategy was coupled with the model. After that, particle swarm optimization (PSO) was employed to optimize the model. The classification accuracy was 100% for testing apples via the SD-SG-PCA-PSO-BPNN model combined with a Gaussian DLRND strategy. Then, quantitative assessments of apple SSC values were performed. The correlation coefficient (r) and root-square-mean error for prediction (RMSEP) in testing apples were 0.998 and 0.112 °Brix, surpassing a commercial fructose meter. The results demonstrate that Vis spectroscopy combined with the proposed synthetic model has significant value in qualitative and quantitative assessments of apple quality.

20.
J Biophotonics ; 16(3): e202200304, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36377642

RESUMEN

In this work, the photoacoustic (PA) quantitative measurement of blood glucose concentration (BGC) influenced by multiple factors was firstly investigated. A set of PA detection system of blood glucose considering the comprehensive influence of five factors was established. The PA signals and peak-to-peak values (PPVs) of 625 rabbit whole blood were obtained under 625 influence combinations. Due to the accurate measurement of BGC limited by the overlap PA signals, wavelet neural network (WNN) was utilized to train the PPVs of blood glucose for 500 rabbit blood. The mean square error (MSE) of BGC for 125 testing blood was approximately 6.5782 mmol/L. To decrease the MSE, the parameters of WNN were optimized by particle swarm optimization (PSO), that is, PSO-WNN algorithm was employed. Under the optimal parameters, MSE of BGC was decreased to approximately 0.48005 mmol/L. To further improve the prediction accuracy of BGC, an improved nonlinear dynamic inertia weight (NDIW) strategy of PSO was proposed, and compared with other two kinds of dynamic inertia weight strategies. Under the optimal parameters, the MSE of BGC was decreased to approximately 0.2635 mmol/L. The comparison of nine algorithms demonstrate that the PA technique combined with PSO-WNN and the improved NDIW strategy is significant in the quantitative measurement of blood glucose influenced by multiple factors.


Asunto(s)
Redes Neurales de la Computación , Técnicas Fotoacústicas , Glucemia/análisis , Animales , Conejos , Técnicas Fotoacústicas/métodos , Algoritmos , Dinámicas no Lineales
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