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1.
J Sep Sci ; 47(3): e2300745, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38356226

RESUMEN

Understanding and comparing the applicability of electromembrane extraction (EME) and liquid-phase microextraction (LPME) is crucial for selecting an appropriate microextraction approach. In this work, EME and LPME based on supported liquid membranes were compared using biological samples, including whole blood, urine, saliva, and liver tissue. After optimization, efficient EME and LPME of clozapine from four biological samples were achieved. EME provided higher recovery and faster mass transfer for blood and liver tissue than LPME. These advantages were attributed to the electric field disrupting clozapine binding to interfering substances. For urine and saliva, EME demonstrated similar recoveries while achieving faster mass transfer rates. Finally, efficient EME and LPME were validated and evaluated combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS). The coefficient of determination of all methods was greater than 0.999, and all methods showed acceptable reproducibility (≤14%), accuracy (90%-110%), and matrix effect (85%-112%). For liver and blood with high viscosity and complex matrices, EME-LC-MS/MS provided better sensitivity than LPME-LC-MS/MS. The above results indicated that both EME and LPME could be used to isolate non-polar basic drugs from different biological samples, although EME demonstrated higher recovery rates for liver tissue and blood.


Asunto(s)
Clozapina , Microextracción en Fase Líquida , Cromatografía Liquida , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem , Microextracción en Fase Líquida/métodos , Membranas Artificiales
2.
BMC Musculoskelet Disord ; 25(1): 622, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103800

RESUMEN

OBJECTIVE: The management of length-unstable femoral shaft fractures(LUFSFs) in pediatric patients is still controversial. This study aims to explore the clinical efficacy of ultrasound-guided closed reduction combined with external fixation for treating LUFSFs in children. METHODS: We conducted a retrospective analysis of clinical data from 19 pediatric patients with LUFSFs who underwent ultrasound-guided closed reduction and external fixation between January 2018 and January 2023. Ultrasound was employed not only to facilitate closed reduction of the fracture but also to guide real-time insertion of Schanz pins and monitor pin length as it traversed the opposite cortex. Surgical time, intraoperative fluoroscopy count, hospital stay length, fracture fixation duration, complication incidence, fracture reduction quality at the final follow-up were recorded. RESULTS: The patients' average age was 7.5 years( range: 5 to 11 years). The mean surgical duration was 70.4 min (range: 48-105 min), and the average intraoperative fluoroscopy count was 6.5 (range: 2-16). Fracture fixation lasted an average of 10.9 weeks (range: 7-20 weeks). All patients were followed up for more than one year. 6 cases of superficial pin tract infection occurred, which resolved with oral antibiotics and enhanced needle tract care. No deep infections were observed. Temporary stiffness of the knee joint was observed in 2 patients. According to Flynn's efficacy evaluation system, fracture reduction quality at the final follow-up was rated as excellent in 11 cases and satisfactory in 8 cases, yielding a combined success rate of 100% (19/19). CONCLUSIONS: The technique of ultrasound-guided closed reduction combined with external fixation offers favorable outcomes for children aged 5 to 11 years with LUFSFs, reducing reliance on fluoroscopic guidance.


Asunto(s)
Fracturas del Fémur , Fijación de Fractura , Ultrasonografía Intervencional , Humanos , Niño , Estudios Retrospectivos , Femenino , Preescolar , Fracturas del Fémur/cirugía , Fracturas del Fémur/diagnóstico por imagen , Masculino , Ultrasonografía Intervencional/métodos , Fijación de Fractura/métodos , Reducción Cerrada/métodos , Resultado del Tratamiento , Clavos Ortopédicos , Tempo Operativo
3.
Mikrochim Acta ; 190(4): 151, 2023 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-36952093

RESUMEN

The development of molecularly imprinted monolith (MIM) for pipette-tip solid-phase extraction (PT-SPE) for sample pretreatment is challenging . In this work, a wax-based molecularly imprinted monolith (WMIM) was successfully prepared with a hybrid method by integration of the traditional packing SPE column and MIM, including preparation of the salt column inside the pipette, polymerization of wax-based imprinted column (WIC) outside the pipette, and immobilization of WIC inside the pipette tip. To ensure the penetration of samples and solvents during the PT-SPE, micrometer-range interconnected macropores were tailor-made via the salt-template sacrifice method. For the production of high affinity imprinted sites within the WIC, octadecanoic acid was used as functional monomer in the paraffin matrix. In terms of the adsorption property, the synthesized WIC exhibited a specific affinity to cardiovascular drugs, with an imprinting factor (IF) of 4.8 for the target analyte. Moreover, the WMIM-based PT-SPE was coupled with fluorescence spectrophotometry for the target propranolol determination  (the excitation and emission wavelengths were 294 nm and 343 nm, respectively). This analytical method showed high recovery of target detection in different real samples (R > 90%), good sensitivity, and accuracy (R2 = 0.99, LOD = 0.03 ng mL-1). We believe this work could provide a significant contribution  for the fabrication of MIM and promote an emerging trend of developing elution-free materials for sample pretreatment.


Asunto(s)
Impresión Molecular , Impresión Molecular/métodos , Polímeros , Cromatografía Líquida de Alta Presión , Extracción en Fase Sólida/métodos , Solventes
4.
Molecules ; 28(20)2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37894582

RESUMEN

Molecularly imprinted polymers (MIPs) have gained significant attention as artificial receptors due to their low cost, mild operating conditions, and excellent selectivity. To optimize the synthesis process and enhance the recognition performance, various support materials for molecular imprinting have been explored as a crucial research direction. Yeast, a biological material, offers advantages such as being green and environmentally friendly, low cost, and easy availability, making it a promising supporting substrate in the molecular imprinting process. We focus on the preparation of different types of MIPs involving yeast and elaborate on the specific roles it plays in each case. Additionally, we discuss the advantages and limitations of yeast in the preparation of MIPs and conclude with the challenges and future development trends of yeast in molecular imprinting research.


Asunto(s)
Impresión Molecular , Polímeros Impresos Molecularmente , Saccharomyces cerevisiae , Polímeros/química , Polimerizacion
5.
Chin J Traumatol ; 26(1): 2-7, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36137934

RESUMEN

Pediatric acute hyperextension spinal cord injury (SCI) named as PAHSCI by us, is a special type of thoracolumbar SCI without radiographic abnormality and highly related to back-bend in dance training, which has been increasingly reported. At present, it has become the leading cause of SCI in children, and brings a heavy social and economic burden. Both domestic and foreign academic institutions and dance education organizations lack a correct understanding of PAHSCI and relevant standards, specifications or guidelines. In order to provide standardized guidance, the expert team formulated this guideline based on the principles of science and practicability, starting from the diagnosis, differential diagnosis, etiology, admission evaluation, treatment, complications and prevention. This guideline puts forward 23 recommendations for 14 related issues.


Asunto(s)
Traumatismos de la Médula Espinal , Niño , Humanos , Traumatismos de la Médula Espinal/diagnóstico , Traumatismos de la Médula Espinal/terapia , Traumatismos de la Médula Espinal/complicaciones , Médula Espinal
6.
Mikrochim Acta ; 189(9): 324, 2022 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-35939150

RESUMEN

An electromembrane microextraction (EME)-assisted fluorescent molecularly imprinted polymer (MIP) sensing method is presented for detecting the total cathinone drugs in urine samples. In this detection system, the clean-up ability of EME eliminated the matrix effects on both target binding with MIPs and the luminescence of the fluorophore in the sensor. Moreover, by optimizing the extraction conditions of EME, different cathinone drugs with a same concentration show a same response on the single aggregation induced emission (AIE) based MIP (AIE-MIP) sensor (λex = 360 nm, λem = 467 nm). The recoveries were 57.9% for cathinone (CAT) and 78.2% for methcathinone (MCAT). The EME-assisted "light-up" AIE-MIP sensing method displayed excellent performance with a linear range of 2.0-12.0 µmol L-1 and a linear determination coefficient (R2) of 0.99. The limit of detection (LOD) value for EME-assisted "light-up" AIE-MIP sensing method was 0.3 µmol L-1. The relative standard deviation (RSD) values for the detection were found to be within the range 2.0-12.0%. To the best of our knowledge, this is the first time that determination of total illicit drugs with a single fluorescent MIP sensor was achieved and also the first utilization of sample preparation to tune the sensing signal of the sensor to be reported. We believe that this versatile combination of fluorescent MIP sensor and sample preparation can be used as a common protocol for sensing the total amount of a group of analytes in various fields.


Asunto(s)
Alcaloides , Impresión Molecular , Colorantes , Límite de Detección , Impresión Molecular/métodos , Polímeros
7.
Molecules ; 27(21)2022 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-36364181

RESUMEN

The separation and detection of flavonoids from various natural products have attracted increasing attention in the field of natural product research and development. Depending on the high specificity of molecularly imprinted polymers (MIPs), MIPs are proposed as efficient adsorbents for the selective extraction and separation of flavonoids from complex samples. At present, a comprehensive review article to summarize the separation and purification of flavonoids using molecular imprinting, and the employment of MIP-based sensors for the detection of flavonoids is still lacking. Here, we reviewed the general preparation methods of MIPs towards flavonoids, including bulk polymerization, precipitation polymerization, surface imprinting and emulsion polymerization. Additionally, a variety of applications of MIPs towards flavonoids are summarized, such as the different forms of MIP-based solid phase extraction (SPE) for the separation of flavonoids, and the MIP-based sensors for the detection of flavonoids. Finally, we discussed the advantages and disadvantages of the current synthetic methods for preparing MIPs of flavonoids and prospected the approaches for detecting flavonoids in the future. The purpose of this review is to provide helpful suggestions for the novel preparation methods of MIPs for the extraction of flavonoids and emerging applications of MIPs for the detection of flavonoids from natural products and biological samples.


Asunto(s)
Productos Biológicos , Impresión Molecular , Flavonoides , Polímeros Impresos Molecularmente , Polímeros , Impresión Molecular/métodos , Extracción en Fase Sólida/métodos
9.
Anal Chem ; 93(33): 11488-11496, 2021 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34383461

RESUMEN

Polymerase chain reaction (PCR) technology has become the cornerstone of DNA analysis. However, special samples (e.g., forensic samples, soil, food, and mineral medicine) may contain powerful PCR inhibitors. High levels of inhibitors can hardly be sufficiently removed by conventional DNA extraction approaches and may result in the complete failure of PCR. In this work, the removal of PCR inhibitors by electromembrane extraction (EME) was investigated for the first time. To demonstrate the universality of the approach, EME formats with and without supported membranes (termed parallel-EME and µ-EME, respectively) were employed, and both anionic [humic acid (HA)] and cationic (Ca2+) PCR inhibitors were used as models. During EME, charged inhibitors in the sample migrate into the liquid membrane in the presence of an electric field and might further leech into the waste solution, while PCR analytes remain in the sample. After EME, the clearance values for HA at 0.2 and 2.5 mg mL-1 were 94 and 85%, respectively, and that for Ca2+ (275 mM) was 63%. Forensic PCR-short tandem repeat (PCR-STR) genotyping showed that EME significantly reduced the interference by HA in PCR-STR analysis and displayed a higher HA purge capability compared to existing methods. Furthermore, by combining EME with liquid-liquid extraction or solid-phase extraction, satisfactory STR profiles were obtained from HA-rich blood samples. In addition, false-negative reports of bacterial detection in mineral medicine and shrimps were avoided after the removal of Ca2+ by µ-EME. Our research demonstrates the great potential of EME for the purification of DNA samples containing high-level PCR inhibitors and opens up a new application direction for EME.


Asunto(s)
Electricidad , Membranas Artificiales , Aniones , Cationes , Reacción en Cadena de la Polimerasa
10.
Anal Chem ; 93(42): 14323-14333, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34648282

RESUMEN

Fluorescent aptamer beacons (FABs) are a major category of biosensors widely used in environmental analysis. However, due to their low compatibility, it is difficult to use the common FABs for biological samples. To overcome this challenge, construction of FABs with complex structures to adapt the nature of biological samples is currently in progress in this field. Unlike previous works, we moved our range of vision from the FAB itself to the biological sample. Inspired by this idea, in this work, flat membrane-based liquid-phase microextraction (FM-LPME) with sufficient sample cleanup and preconcentration capacities was integrated with FABs. With the merits of both FM-LPME and FABs, the integrated LPME-FAB system displayed a clear synergistic enhancement for target analysis. Specifically, LPME in the LPME-FAB system provided purified and enriched Hg2+ for the FAB recognition, while the FAB recognition event promoted the extraction efficiency of LPME. Due to superior performances, the LPME-FAB system achieved highly sensitive analysis of Hg2+ in urine samples with a detection limit of 27 nM and accuracies in the range of 98-113%. To the best of our knowledge, this is the first time that an integrated LPME-FAB system was constructed for target analysis in biological samples. We believe that this study will provide a new insight into the next generation of biosensors, where the integration of sample preparation with detection probes is as important as the design of complex probes in the field of bioanalysis.


Asunto(s)
Microextracción en Fase Líquida
11.
J Shoulder Elbow Surg ; 30(9): 2113-2119, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33639301

RESUMEN

BACKGROUND: It is difficult for surgeons to successfully perform closed reduction and percutaneous pinning on displaced and rotated lateral condylar humeral fractures in children. This study aimed to introduce an ultrasound-assisted closed reduction and percutaneous pinning technique and determine its usefulness in the treatment of displaced and rotated lateral condylar humeral fractures in children. METHODS: Between 2013 and 2018, 42 of 44 displaced and rotated pediatric lateral humeral condylar fractures were successfully treated with ultrasound-assisted closed reduction and percutaneous pinning. All surgical procedures were performed by 1 senior surgeon. Demographic and clinical data including age, sex, affected side, time from injury to reduction, operative time, and number of intraoperative radiographs (without fluoroscopy) were analyzed. Postoperative data were evaluated in terms of Kirschner wire in situ duration, follow-up duration, range of motion, carrying angle, cosmetic result, and complications. RESULTS: The average operative time was 67 minutes from 2013 to 2015 and 51 minutes from 2016 to 2018. All 42 patients who successfully underwent ultrasound-assisted closed reduction were followed up for >3 months, and 31 of 42 patients were followed up for >1 year. Among these 31 patients, the range-of-motion outcomes were excellent in 25 and good in 6. The carrying angle outcomes were excellent in 28 patients and good in 3. Two instances of wire infection, 9 instances of granulation tissue hyperplasia, and 23 instances of lateral spur formation occurred. No nonunion, avascular necrosis, or postoperative nerve issues were identified. CONCLUSIONS: The surgical technique of ultrasound-assisted closed reduction and percutaneous pinning presented in this study can effectively help surgeons reduce displaced and rotated lateral condylar humeral fractures in children to avoid some open reductions and achieve satisfactory outcomes.


Asunto(s)
Fijación Intramedular de Fracturas , Fracturas del Húmero , Niño , Fijación Interna de Fracturas , Humanos , Fracturas del Húmero/diagnóstico por imagen , Fracturas del Húmero/cirugía , Húmero , Estudios Retrospectivos , Resultado del Tratamiento
12.
J Pediatr Orthop ; 40(4): e287-e292, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31834243

RESUMEN

BACKGROUND: Pediatric lateral humeral condyle fractures (LHCFs) are sometimes misdiagnosed and inappropriately treated on the basis of x-ray radiographs because cartilage cannot be seen on radiographs. However, as a useful technique, transverse ultrasonography can accurately and readily determine the integrity of the cartilage hinge in pediatric LHCFs. The purpose of this study was to assess the reliability of the Jakob classification, the treatment plan, and the necessity for further examination of pediatric LHCFs with the use of x-ray with and without transverse ultrasound images. METHODS: Five pediatric orthopaedic surgeons with different levels of experience evaluated 62 cases on the basis of the use of x-ray alone and x-ray combined with transverse ultrasound images. These 2 types of evaluations were repeated after an interval of 4 to 6 weeks. At the time of each evaluation, all observers were asked to classify the fractures according to the Jakob classification, to formulate treatment plans, and to determine whether further examinations were required. RESULTS: After the training of transverse ultrasound image interpretation, the interobserver reliability of the Jakob classification significantly improved from fair (a kappa of 0.54) to moderate (a kappa of 0.71) with the addition of transverse ultrasound images. The treatment plan was changed from conservative treatment to surgical treatment in 7% of the ratings but from surgical treatment to conservative treatment in 15% of the ratings after reviewing the ultrasound images, and the difference was statistically significant (P=0.003). CONCLUSIONS: The use of the Jakob classification and a treatment plan for pediatric LHCFs can be optimized by the addition of transverse ultrasound images, especially after training for transverse ultrasound image interpretation. LEVEL OF EVIDENCE: Level III-diagnostic study.


Asunto(s)
Fracturas del Húmero , Húmero/diagnóstico por imagen , Radiografía/métodos , Ultrasonografía/métodos , Niño , China , Errores Diagnósticos/prevención & control , Femenino , Humanos , Fracturas del Húmero/clasificación , Fracturas del Húmero/diagnóstico por imagen , Masculino , Variaciones Dependientes del Observador , Planificación de Atención al Paciente , Selección de Paciente , Reproducibilidad de los Resultados
13.
Anal Chem ; 91(13): 8267-8273, 2019 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-31141346

RESUMEN

Isolation of substances by liquid-phase microextraction (LPME) or electromembrane extraction (EME) is becoming more and more important in analytical chemistry. However, the understanding of the mass transfer in LPME and EME is limited, especially for highly concentrated samples. In this work, the mass transfer in LPME and EME from aqueous samples (0.5-200 mg L-1) was studied in terms of recovery, equilibrium time, flux, and mass transfer capacity. In both EME and LPME, high recoveries were achieved at low analyte concentration, and the recoveries decreased at high analyte concentration. For EME, the loss in recovery was partly compensated by increasing the extraction voltage (from 50 to 200 V), while the LPME recovery at high analyte concentration was improved by increasing the extraction time (from 30 to 180 min). EME was superior in terms of equilibrium time and flux, while LPME provided much higher mass transfer capacity especially for highly concentrated samples. Moreover, the recovery was much more sensitive to high analyte concentrations in EME than in LPME, and the EME recovery decreased significantly above 50 mg L-1, indicating that LPME could be used to isolate analytes in a wider concentration range than EME. We believe that this fundamental study will be of great importance for the selection of a suitable membrane-based microextraction technique.

14.
Int Orthop ; 43(6): 1405-1411, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30980114

RESUMEN

PURPOSE: This study aimed to investigate the radiographic outcomes, rate of redislocation, and avascular necrosis of proximal femoral epiphysis (AVN) in patients aged 24 to 36 months with developmental dysplasia of the hip (DDH) treated by closed reduction (CR) and spica cast immobilization in human position. MATERIAL AND METHODS: We reviewed the medical records of 39 patients (51 hips) aged 24 to 36 months with DDH treated by CR and spica cast immobilization in human position. The Tönnis grade, rate of redislocation and AVN, acetabular index (AI), centre-edge angle (CEA), and Severin radiographic grade were evaluated on plain radiographs. RESULTS: Among the included 39 patients (51 hips), 15 hips (29.4%) were Tönnis grade II, 24 hips (47.1%) were grade III, and 12 hips (23.5%) were grade IV. In 47 hips (92.2%), the ossific nucleus was present at the time of CR. Stable reduction was achieved by CR in 39/51 hips (76.5%) and redislocation occurred in 12/51 hips (23.5%). Among the 12 hips that redislocated, 11 underwent open reduction and one repeated CR. Two out of 40 hips (5%) treated by CR developed AVN. Overall, 54.6% of the hips had satisfactory outcomes (39.2% Severin type I and 17.6% type II), while 45.4% had unsatisfactory outcomes (39.2% Severin type III and 3.9% type IV). Of the 40 hips treated by CR, 57.5% and 42.5% of cases had satisfactory outcomes and residual acetabular dysplasia, respectively. Six out of 11 hips (54.6%) treated by open reduction and pelvic osteotomy had satisfactory outcomes. CONCLUSIONS: Our study showed that stable CR could be achieved in 76.5% of patients aged 24 to 36 months with DDH at the time of index procedure. Satisfactory outcomes can be expected in 56.4% of the cases (5.0% AVN rate), although late acetabular dysplasia may develop in 43.6% of the hips.


Asunto(s)
Luxación Congénita de la Cadera/diagnóstico por imagen , Preescolar , Femenino , Luxación Congénita de la Cadera/cirugía , Humanos , Lactante , Masculino , Osteonecrosis/cirugía , Osteotomía , Radiografía , Procedimientos de Cirugía Plástica , Estudios Retrospectivos , Férulas (Fijadores) , Resultado del Tratamiento
15.
Anal Chem ; 90(20): 11764-11769, 2018 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-30232889

RESUMEN

Detection of heavy metals is of great importance for food safety and environmental analysis. Among various heavy metal ions, mercury ion is one of the most prevalent species. The methods for detection of mercury were numerous, and the T-Hg-T based assay was promising due to its simplicity and compatibility. However, traditional T-Hg-T based methods mainly relied on multiple T-Hg-T to produce enough conformational changes for further detection, which greatly restrained the limit of detection. Hence, we established a branch-migration based fluorescent probe and found that single T-Hg-T could produce strong signals. The sensing mechanism of our method in different reaction modes was explored, and the detection limits were determined to be 18.4 and 14.7 nM in first-order reaction mode and mixed reaction mode, respectively. Moreover, coupled with Endonuclease IV assisted signal amplification, the detection limit could be 1.2 nM, lower than most DNA based fluorometric assays. For practicability, the specificity of our assay toward different interfering ions was investigated and detection of Hg2+ in deionized water and lake water was also achieved with similar recoveries compared to those of atomic fluorescence spectrometry, which demonstrated the practicability of our method in real samples. Definitely, the proposed branch migration probe would be a promising substitution for current DNA probes based on recognition of multiple T-Hg-T and we anticipate it to be widely adopted in food and environmental analysis.


Asunto(s)
Colorantes Fluorescentes/análisis , Colorantes Fluorescentes/química , Mercurio/análisis , Sondas de ADN , Fluorometría , Mercurio/química
16.
Anal Chem ; 87(13): 6951-7, 2015 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-26039105

RESUMEN

Electromembrane extraction (EME) and liquid-phase microextraction (LPME) were combined in a single step for the first time to realize simultaneous and clear group separation of basic and acidic drugs. Using 2-nitrophenyl octyl ether as the supported liquid membrane (SLM) for EME and dihexyl ether as the SLM for LPME, basic and acidic drugs were extracted and separated simultaneously from a low pH sample by EME and LPME, respectively. After 15 min of extraction, basic drugs (citalopram and sertraline) were exhaustively extracted, whereas the recoveries for acidic drugs (ketoprofen and ibuprofen) were in the range of 76%-86%. Longer extraction time provided higher recoveries for the acidic drugs, but this somewhat deteriorated the group separation. Matrices effects from the coexisting acidic drugs/basic drugs were tested, and we observed that simultaneous EME/LPME was not affected by coexisting drugs at high concentration. This approach was further investigated from human plasma. Extraction recoveries were strongly dependent on dilution of plasma with buffer and on extraction time. Finally, this simultaneous EME/LPME approach was evaluated in combination with liquid chromatography (LC)-MS. The linearity ranges for the basic and acidic drugs were 10-600 ng/mL and 1-60 µg/mL, respectively, with R(2) > 0.997 for all analytes. The repeatability at three different levels for all analytes was less than 15%. The limits of quantification (LOQ, S/N = 10) were found to be 4.0-6.3 ng/mL and 0.6-0.9 µg/mL for basic and acidic drugs, respectively. Simultaneous EME/LPME enabled efficient group separation of basic and acidic analytes under optimum experimental conditions for both EME and LPME.


Asunto(s)
Microextracción en Fase Líquida , Membranas Artificiales , Preparaciones Farmacéuticas/aislamiento & purificación , Cromatografía Liquida , Espectrometría de Masas
17.
Acta Radiol ; 55(6): 745-52, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24060815

RESUMEN

BACKGROUND: Ultrasound can be used for the diagnosis of elbow injuries in infants and toddlers. However, ultrasound is highly operator-dependent and accurate ultrasound examinations require a complete understanding of the complex anatomy of the elbow joint. PURPOSE: To report the normal ultrasound anatomy of the elbow, particularly of the humeroulnar joint, in infants and toddlers. MATERIAL AND METHOD: Thirty subjects aged <3 years with no history of elbow injuries underwent ultrasound examinations of the elbow joint from six directions: (i) lateral to the humeroradial joint; (ii) anterior to the humeroradial joint; (iii) posterior to the humeroradial joint; (iv) medial to the humeroulnar joint; (v) anterior to the humeroulnar joint; and (vi) posterior to the humeroulnar joint. RESULTS: The appearance of the humeroradial joint observed from three directions was similar and resembled a pair of double fists ("double-breast sign"). The appearance of the humeroulnar joint observed from three directions was different, which is related to the irregular morphology of the medial sides of the humerus and ulna. Anteroposteriorly, the coronoid and olecranon epiphyses and coronoid fossa appear anteriorly and the olecranon and trochlear epiphyses and olecranon fossa appear posteriorly, resembling a "check-mark sign". The medial epicondyle, cubital tunnel and distal humerus appear together ("double-hump sign"). The "anterior hump" is the medial epicondyle and is always higher than the "posterior hump", which is the bony protrusion on the articular surface of the distal humerus. The ultrasound signal of cortical bone in the metaphysis of the distal humerus is continuous with that of the epiphysis of the medial epicondyle. CONCLUSION: Ultrasound is useful for the diagnosis of elbow injuries in infants and toddlers.


Asunto(s)
Articulación del Codo/anatomía & histología , Articulación del Codo/diagnóstico por imagen , Preescolar , Femenino , Humanos , Lactante , Masculino , Estudios Prospectivos , Valores de Referencia , Reproducibilidad de los Resultados , Ultrasonografía
18.
Angew Chem Int Ed Engl ; 53(40): 10687-90, 2014 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-25111359

RESUMEN

The tendency of bacteria to assemble at oil-water interfaces can be utilized to create microbial recognition sites on the surface of polymer beads. In this work, two different groups of bacteria were first treated with acryloyl-functionalized chitosan and then used to stabilize an oil-in-water emulsion composed of cross-linking monomers that were dispersed in aqueous buffer. Polymerization of the oil phase followed by removal of the bacterial template resulted in well-defined polymer beads bearing bacterial imprints. Chemical passivation of chitosan and cell displacement assays indicate that the bacterial recognition on the polymer beads was dependent on the nature of the pre-polymer and the target bacteria. The functional materials for microbial recognition show great potential for constructing cell-cell communication networks, biosensors, and new platforms for testing antibiotic drugs.


Asunto(s)
Bacterias/citología , Quitosano/análogos & derivados , Emulsiones/química , Impresión Molecular/métodos , Aceites/química , Polímeros/química , Polimerizacion , Propiedades de Superficie , Agua/química
19.
Environ Sci Pollut Res Int ; 31(5): 7828-7836, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38170364

RESUMEN

Previous works have shown that hematological system can be affected by exposure to lead; however, the effects of multiple metals on platelets remain elusive within the population from metal-contaminated areas. Hence, the study enrolled 609 participants, with 396 from a metal-exposed area and 213 from a control area. Platelet count (PLT), mean platelet volume (MPV), thrombocytocrit (PCT), platelet to large cell ratio (P-LCR), and platelet distribution width (PDW) were selected to evaluate platelet function. Stepwise regression and Lasso regression were utilized to identify the most influential metals. Moreover, the generalized linear model (GLM), Bayesian kernel machine regression (BKMR) models, and quantile g-computation were employed to estimate the individual or combined effects associations between 12 urinary metals and platelet indices. The results revealed all metals except vanadium, copper, strontium, and molybdenum were significantly higher in the exposed group. The GLM models indicated that urinary metals, including lead, antimony, and arsenic, exhibited associations with PLT, MPV, P-LCR, and PDW. Quantile g-computation and BKMR demonstrated negative correlations between metal mixtures and MPV as well as PDW. In conclusion, the study highlights the associations between multiple metal exposures and platelet indices, suggesting that elevated levels of the metal mixture may impede platelet activation in the population in metal-contaminated areas.


Asunto(s)
Plomo , Volúmen Plaquetario Medio , Humanos , Estudios Transversales , Teorema de Bayes , China
20.
J Chromatogr A ; 1714: 464550, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38043167

RESUMEN

Molecularly imprinted polymers (MIPs) possess high specific cavities towards the template molecules, thus solid-phase extraction (SPE) based on MIPs using the target as the template has been widely used for selective extraction. However, the performance of SPE depends strongly on the shape and the distribution of the MIP sorbents, and rapid synthesis of MIPs with uniform particles remains a challenge. Our previous studies have shown that reflux precipitation polymerization (RPP) was a simple and rapid method for the synthesis of uniform MIPs. However, synthesis of MIPs by RPP for a group of targets using only one of the targets as the template has rarely been reported. In this work, MIPs with specific recognition capability for a group of quinolone antibiotics were synthesized for the first time via RPP with only ofloxacin as the template. The synthesized MIPs displayed good adsorption performance and selectivity (IF > 3.5) towards five quinolones, and subsequently were used as SPE adsorbents. Based on this MIPs-SPE, after systematic optimization of the SPE operation parameters during loading, washing and elution, an efficient and sensitive enough SPE method for separation and enrichment of the five quinolones in urine was developed and evaluated in combination with LC-MS/MS. The results showed that MIPs-SPE-LC-MS/MS has a good correlation (R2 ≥ 0.9961) in the linear range of 1-500 µg L-1. The limit of detection (LOD) and limit of quantification (LOQ) for the five quinolones were 0.10-0.14 µg L-1 and 0.32-0.48 µg L-1, respectively. In addition, the proposed method demonstrated good reproducibility (≤ 13 %) and high accuracy (92 %-113 %). We are confident that this method holds significant promise for the analysis of quinolones within the contexts of forensic medicine, epidemiology, and environmental chemistry.


Asunto(s)
Impresión Molecular , Quinolonas , Polímeros Impresos Molecularmente , Cromatografía Liquida , Polimerizacion , Reproducibilidad de los Resultados , Impresión Molecular/métodos , Polímeros/química , Espectrometría de Masas en Tándem , Extracción en Fase Sólida/métodos , Antibacterianos , Adsorción
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