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1.
J Vasc Interv Radiol ; 34(12): 2208-2212, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37652297

RESUMEN

This study aimed to investigate the feasibility of ultrasound (US)-guidance in reducing adverse event (AE) rates when using Angioseal device during antegrade lower limb angioplasty via common femoral artery access. From December 2016 to November 2022, 1,322 patients were identified, including 1,131 (85.6%) patients who underwent US-guided closure and 191 (14.4%) who underwent non-US-guided closure. Moderate AEs were encountered in 10 (5.2%) patients in the non-US-guided closure group compared to 38 (3.4%) patients in the US-guided closure group (P = .208). Severe AEs were encountered in 4 (2.1%) patients in the non-US-guided closure group compared to 3 (0.3%) patients in the US-guided closure group (P = .010). Overall AEs occurred in 14 (7.3%) patients in the non-US-guided closure group compared to 41 (3.6%) patients in the US-guided closure group (P = .029). Binary logistic regression showed that only non-US guidance was an independent risk factor for the occurrence of severe AEs (P = .008).


Asunto(s)
Arteria Femoral , Técnicas Hemostáticas , Humanos , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/cirugía , Resultado del Tratamiento , Punciones , Extremidad Inferior , Estudios Retrospectivos
2.
Aging Clin Exp Res ; 32(9): 1801-1807, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31598913

RESUMEN

BACKGROUND: Type 2 myocardial infarction (T2MI) refers to myocardial ischemic necrosis as a result of myocardial oxygen supply/demand mismatch, which are common comorbidities of critically ill patients. The purpose of this study was to investigate the incidence rate and risks of T2MI in critically ill elderly patients and further elucidate in-hospital prognostic factors. METHODS: A total of 223 critically ill elderly patients admitted to our hospital from October 2016 to September 2018 were recruited. The clinical data and the in-hospital mortality rate were compared between the T2MI and non-T2MI groups. Multivariate linear regression analysis was used to identify independent factors related to T2MI. The clinical data and incidence of T2MI were also compared between patients who survived and those who died; multivariate regression analysis was used to identify independent risk factors for in-hospital death and survival analysis was conducted. RESULTS: In this study, the incidence of T2MI was 24.2% (54/223), and the mortality rate of critically ill elderly patients was 39.0% (87/223). Multivariate linear regression analysis showed that severe hypoxemia, arrhythmia, shock, and multiple organ dysfunction syndrome (MODS) were independent risk factors of T2MI. Compared to the survival patients, the use of mechanical ventilation, the incidence of T2MI, APACHE II score, troponin T, high-sensitivity C-reactive protein, and procalcitonin levels were significantly higher in patients who died, while the estimated glomerular filtration rate (eGFR) was significantly decreased (all P < 0.05). In-hospital mortality was significantly increased in patients with T2MI (59.3% vs. 32.5%, P < 0.001). After adjustment for relevant factors, the incidence of T2MI, mechanical ventilation required, and eGFR reduction were independent and significant predictors of in-hospital death. CONCLUSIONS: Critically, ill elderly patients have a high incidence of T2MI. In addition to severe hypoxia, shock, and arrhythmia, MODS is also associated with T2MI. At the same time, the risk of in-hospital death is increased in patients with type 2 MI.


Asunto(s)
Enfermedad Crítica , Infarto del Miocardio , Anciano , Hospitales , Humanos , Unidades de Cuidados Intensivos , Infarto del Miocardio/epidemiología , Pronóstico
5.
Angew Chem Int Ed Engl ; 54(40): 11745-9, 2015 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-26308558

RESUMEN

Dimeric, trimeric, and tetrameric cyclic [2]catenanes have been prepared directly through one-pot sodium-ion-templated dynamic imine formation from a diamine and a tetraaldehyde. NaBH4 mediated reduction of the labile imino bonds of these cyclic [2]catenane oligomers, followed by methylation of the resulting secondary amino groups enabled the isolation and characterization of oligomeric cyclic [2]catenanes as stable, covalently linked compounds.

6.
J Sep Sci ; 37(16): 2260-7, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24841359

RESUMEN

A simple, novel, and selective flow-injection solid-phase extraction with inductively coupled plasma optical emission spectrometry method was developed for the speciation of inorganic selenium in environmental water samples. A mesoporous zirconia film was simply introduced to coat coal cinder by means of the sol-gel technique, and the adsorptive performance of the coated material for Se(IV)/Se(VI) was investigated in different media. Both Se(IV) and Se(VI) can be retained quantitatively by the material in HCl/NaOH (pH 1.0-9.0) media, while only Se(IV) was adsorbed quantitatively in sodium acetate buffer (pH 3.5-6.0). Thus, the assay of Se(VI) is based on subtracting Se(IV) from total selenium by controlling different adsorptive media without employing any redox procedure. Under the optimum conditions, the detection limit of Se(IV) is 9.0 ng/L with an enrichment factor of 100, and the relative standard deviation is 3.6% (n = 9, C = 5.0 ng/mL). The developed method was successfully applied to the speciation of inorganic selenium in environmental water samples with satisfactory results. In order to further verify the accuracy of the developed method, it was applied to analysis of total selenium in GSBZ 50031-94 certified reference environmental water, and the determined values coincided with the certified values very well.


Asunto(s)
Selenio/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Circonio/química , Adsorción , Tampones (Química) , Carbón Mineral , Monitoreo del Ambiente/métodos , Agua Dulce/química , Concentración de Iones de Hidrógeno , Compuestos Inorgánicos/química , Límite de Detección , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Oxidación-Reducción , Transición de Fase , Reproducibilidad de los Resultados , Acetato de Sodio/química , Extracción en Fase Sólida , Agua/química
7.
Chin J Cancer Res ; 26(5): 517-24, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25400416

RESUMEN

PURPOSE: To determine the diagnostic performance of 3'-deoxy-3'-(18)F-fluorothymidine positron emission tomography/computed tomography (FLT PET/CT) and FLT PET for evaluating response to chemotherapy in patients with breast cancer. METHODS: Databases such as PubMed (MEDLINE included) and excerpta medica database (EMBASE), were searched for relevant original articles. The included studies were assessed for methodological quality with quality assessment of diagnosis accuracy studies (QUADAS) score tool. Histopathological analysis and/or clinical and/or radiological follow-up for at least 6 months were used as the reference standard. The data were extracted by two reviewers independently to analyze the sensitivity, specificity, summary receiver operating characteristic (SROC) curve, area under the curve (AUC), and heterogeneity. RESULTS: The present study analyzed a total of 4 selected articles. The pool sensitivity was 0.773 [95% confidence interval (CI): 0.594-0.900]. The pooled specificity was 0.685 (95% CI: 0.479-0.849) on basis of FEM. The pooled LR+, LR-, and DOR were 2.874 (1.492-5.538), 0.293 (0.146-0.589), and 14.891 (3.238-68.475), respectively. The AUC was 0.8636 (±0.0655), and the Q* index was 0.7942 (±0.0636). CONCLUSIONS: Our results indicate that (18)F-FLT PET/CT or PET is useful to predict chemotherapy response in breast cancer with reasonable sensitivity, specificity and DOR. However, future larger scale clinical trials will be needed to assess the regimen of (18)F-FLT PET/CT or PET in monitoring the response to chemotherapy in breast cancer patients.

8.
J Vasc Access ; : 11297298241250246, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38708823

RESUMEN

AIM: Arteriovenous fistula (AVF) dysfunction resulting from stenosis or occlusion, is a prevalent issue in end-stage renal failure patients reliant on autogenous AVFs for dialysis. Recently, a distal transradial approach (dTRA) has emerged, offering advantages such as diminished access site complications, better patient comfort and reduced risk of radial artery occlusion. Our study seeks to assess the effectiveness, outcomes and complication rates of employing dTRA for arteriovenous fistuloplasty in Singaporean patients. METHODS: A retrospective review of all dTRA fistuloplasties performed on dysfunctional or slow to mature AVFs from 2017 to 2023 in our institution was performed. Patients with a distal radial artery measuring 2 mm or more with no evidence of occlusion or thrombosis were included. Patients who required central venoplasty or cutting balloon angioplasty were excluded. Outcome measures included technical success, mean procedure duration, complications and post-intervention primary patency at 1, 3 and 6 months. Patients were followed up for 12 months post-intervention. RESULTS: A total of 37 patients were included. 97.3% of patients undergoing dTRA fistuloplasty had radiocephalic fistulas while 2.7% had brachiobasilic fistulas. There was 100% technical success (defined as success in radial artery cannulation, sheath insertion and crossing of stenotic lesions) in our study as all patients successfully underwent fistuloplasty via dTRA approach. One-month patency rate was 97.4%, 3-month patency rate was 92.1% and 6-month patency rate was 86.8%. There were no immediate complications (haematoma, infection, bleeding, pseudoaneurysm, occlusion) of the radial artery post-intervention. CONCLUSION: Our paper illustrates the safety and efficacy of utilising dTRA for arteriovenous fistuloplasty. This approach offers distinct benefits in addressing non-mature or dysfunctional distal forearm arteriovenous fistulas and should be taken into account in anatomically suitable cases.

9.
J Vasc Surg Cases Innov Tech ; 9(4): 101340, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37965113

RESUMEN

Blue toe syndrome can occur due to distal embolization from proximal lesions such as an aortic thrombus. We describe the case of a patient who presented with chronic limb threatening ischemia due to a flow-limiting infrarenal aortic thrombus, with gangrene from distal embolization to the left fifth toe, and was successfully treated with endovascular aortic stent graft insertion. Distal embolization during instrumentation was successfully prevented by using a partially deployed Wallstent (Boston Scientific) as an embolic protection device. The reconstrainable Wallstent device can be considered for distal thromboembolic protection during aortic stenting, in particular, when distal embolization is a concern and commercial devices are not readily available.

10.
Biol Trace Elem Res ; 201(2): 677-682, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35332437

RESUMEN

Dental calculus is a potential material that can be used for assessing chronic exposure to trace heavy metals in oral cavity as it is a long-term reservoir. The aim of this study was to investigate the correlation between dental calculus copper levels and risk of oral submucous fibrosis (OSF) due to chewing dried areca-nut quids in Mainland China. This study included 34 OSF (grade 1) sufferers with dried areca-nut quids chewing as the patient group and 23 healthy individuals without areca-nut chewing as the control group. The dental calculus sample was obtained from all 57 participants and evaluated by inductively coupled plasma mass spectrometry (ICP-MS) for dental calculus level of copper. This work revealed that the mean copper level of dental calculus was significantly higher in OSF (grade 1) sufferers with areca-nut chewing than those in healthy individuals without areca-nut chewing (p < 0.001). This work provided an evidence to support that there may be a positive correlation between elevated levels of copper in dental calculus caused by chewing dried areca-nut quids and an increased risk of developing OSF in Mainland China.


Asunto(s)
Fibrosis de la Submucosa Bucal , Oligoelementos , Humanos , Fibrosis de la Submucosa Bucal/etiología , Cobre/análisis , Areca/efectos adversos , Masticación , Nueces/química , Cálculos Dentales , China , Oligoelementos/análisis
11.
Zhonghua Yi Xue Za Zhi ; 91(35): 2456-8, 2011 Sep 20.
Artículo en Zh | MEDLINE | ID: mdl-22321838

RESUMEN

OBJECTIVE: To evaluate the clinic value of (18)F-FDG PET/CT imaging in differentiation of malignant from benign disease in lung. METHODS: 188 patients underwent (18)F-FDG 45 min early and 2 h delayed PET/CT imaging after intravenous injection of (18)F-FDG. The standardized uptake value (SUV) and retention index (RI) of region of interesting were calculated. The histological diagnosis or clinical findings in a 12 months follow-up period served as the standard of truth. RESULTS: In 114 patients with malignant disease and 74 patients with benign disease, the sensitivity, speciality and accuracy of (18)F-FDG PET/CT imaging in differentiation of malignant from benign lung nodules (diameter more than 10 mm) were 98.2%, 80.0%, and 96.6%, in mediastinal lymph nodes and were 95.7%, 41.7%, and 84.8%, respectively. The sensitivity of (18)F-FDG PET imaging for lung nodules (diameter less than 10 mm) was lower than CT. CONCLUSIONS: Integrated PET/CT imaging provides high sensitivity, specificity and reasonably high accuracy for lung cancer.


Asunto(s)
Tomografía de Emisión de Positrones , Radiofármacos , Fluorodesoxiglucosa F18 , Humanos , Neoplasias Pulmonares , Tomografía Computarizada por Rayos X
12.
J Belg Soc Radiol ; 105(1): 25, 2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-33987526

RESUMEN

This article demonstrates the technique of using a coaxial guiding needle to perform combined percutaneous biopsy and microwave ablation via a single tract. From May 2019 to July 2020, 14 patients underwent combined biopsy and microwave ablation by using a coaxial guiding cannula. Tumors were in the kidney of six patients (43%), the liver of six patients (43%), and the lung in two patients (14%). The diagnostic yield of biopsy was 86% (12/14). Ablation technical success rate was 100%. In conclusion, using a coaxial guiding needle in microwave ablation and biopsy is safe and effective.

13.
Am J Case Rep ; 22: e929048, 2021 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-33750755

RESUMEN

BACKGROUND Malignant disease is a common etiology of superior vena cava syndrome (SVCS). Being a medical emergency, it often requires rapid diagnostic evaluation and therapy. Transcaval biopsy and endovascular stenting in a single-setting has been described, but only in a handful of cases. These cases utilized intra-operative venograms. In this study, we also used intra-operative cone beam computed tomography (CBCT) to increase the safety and efficacy of such single-setting procedures. CASE REPORT From January 2017 to July 2019, there were 5 patients with malignant SVCS who underwent single-setting superior vena cava biopsy and endovascular stenting utilizing intra-operative CBCT as an adjunct. Demographic data, clinical presentation, investigation results, procedural details, and patient outcomes were recorded. CBCT was utilized in all cases to optimize sampling of biopsies, visualize subsequent stent positioning, and for early detection of procedure-related complications. Transcaval biopsy was diagnostic in 4 of the 5 patients. Endovascular stents were deployed successfully in all cases, with post-stenting venogram demonstrating relief of prior obstructed segments. One patient had a complication of an apical pneumothorax, with no associated long-term pneumothorax-related morbidity or mortality. CONCLUSIONS This study demonstrates that single-setting transcaval biopsy and stenting in the context of malignant SVCS is a cost-efficient, safe, and feasible approach. In addition, the additional use of intra-operative CBCT is a useful tool to increase procedure efficacy and safety.


Asunto(s)
Síndrome de la Vena Cava Superior , Vena Cava Superior , Biopsia , Tomografía Computarizada de Haz Cónico , Humanos , Stents , Síndrome de la Vena Cava Superior/diagnóstico por imagen , Síndrome de la Vena Cava Superior/etiología , Síndrome de la Vena Cava Superior/cirugía , Resultado del Tratamiento , Vena Cava Superior/diagnóstico por imagen , Vena Cava Superior/cirugía
14.
J Sep Sci ; 33(19): 3068-74, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20603837

RESUMEN

An on-column preconcentration technique, pH-mediated acid stacking, was used in this study to improve the sensitivity of MEKC-UV analysis of IgG in human serum. Various parameters affecting pH-mediated acid stacking were optimized systematically. To eliminate the matrix interferences of human serum and to combine the sample pretreatment procedure with the detection methodology, silica-coated Fe(3)O(4) magnetic nanoparticles modified with N-(2-aminoethyl)-3-aminopropyl-trimethoxysilane were prepared and employed as solid phase extraction adsorbent to remove the abundant HSA from human serum. HSA was quantitatively removed by silica-coated Fe(3)O(4) magnetic nanoparticles modified with N-(2-aminoethyl)-3-aminopropyl-trimethoxysilanes without retaining IgG at pH 9.3. Under the optimum conditions, the sensitivity of IgG was improved 40.3-fold using a 100 s electrokinetic injection as compared with a 6 s hydrodynamic injection. The detection limit of IgG was found to be 0.1 mg/L, and the proposed method was successfully applied for the determination of IgG in human serum with satisfactory results.


Asunto(s)
Cromatografía Capilar Electrocinética Micelar/métodos , Inmunoglobulina G/sangre , Compuestos Férricos/química , Humanos , Concentración de Iones de Hidrógeno , Nanopartículas del Metal/química , Extracción en Fase Sólida
15.
Ann Acad Med Singap ; 49(2): 65-71, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32246707

RESUMEN

INTRODUCTION: This study aimed to identify imaging features on single-sequence noncontrast magnetic resonance imaging (MRI) that differentiate the vestibular ganglion from small intracanalicular schwannomas. MATERIALS AND METHODS: Ninety patients (42 men and 48 women; age: 24‒87 years old) with 102 internal auditory canal (IAC) nodules (59 vestibular ganglia and 43 intracanalicular schwannoma) who underwent both single-sequence T2-weighted (T2W) non-contrast enhanced MRI studies and contrast-enhanced T1-weighted (T1W) MRI studies between May 2012 and April 2017 were evaluated. The length, width, distance to the IAC fundus and length/width ratios for all lesions were obtained and compared among groups. Diagnostic performance and cutoff values of the parameters were evaluated with receiver operating characteristics curve analysis. Area under the curve (AUC) value was calculated. RESULTS: Vestibular ganglia have significantly smaller lengths and widths compared to intracanalicular vestibular schwannomas (1.7 ± 0.4 mm and 1.0 ± 0.2 mm versus 5.6 ± 3.0 mm and 3.7 ± 1.5 mm). They are more fusiform in shape compared to vestibular schwannomas (length/width ratio: 1.8 ± 0.4 versus 1.5 ± 0.4). The lesion width demonstrated the highest diagnostic performance (AUC: 0.998). Using a cutoff width of <1.3 mm, the sensitivity, specificity and overall accuracy for diagnosing vestibular ganglia were 97% (57/59), 100% (43/43) and 98% (100/102), respectively. CONCLUSION: Vestibular ganglia may mimic intracanalicular vestibular schwannomas on a single-sequence T2W MRI. However, a fusiform shape and width <1.3 mm increases confidence in the diagnosis of ganglia. Identifying the vestibular ganglion on single-sequence T2W MRI studies may obviate the need for a contrast-enhanced MRI, reducing the risks of contrast administration, additional scanning time and cost.


Asunto(s)
Imagen por Resonancia Magnética , Neuroma Acústico/diagnóstico por imagen , Canales Semicirculares , Ganglio Espiral de la Cóclea , Adulto , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Curva ROC , Estudios Retrospectivos , Adulto Joven
16.
Chem Asian J ; 15(22): 3599-3619, 2020 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-32931134

RESUMEN

Photocatalysis via direct solar-to-chemical energy conversion is an intriguing approach for alleviating the pressure of high energy consumption caused by social development. However, photocatalytic efficiency is greatly restricted by unsatisfactory light-harvesting capacity, high carrier recombination rates, and sluggish reaction kinetics. Indeed, vacancy engineering is an attractive strategy to regulate photocatalytic reaction performance to maximize the utilization and storage of solar energy. In this review, we summarize recent progress about the important roles of vacancy defects on solar-driven photocatalytic applications. The current advanced characterization techniques, especially for in situ/operando techniques, are first presented for elucidating the structure-performance relationships of defective semiconductors in photocatalysis. Subsequently, the crucial roles of vacancies in enhancing photocatalytic performance are highlighted from three important processes: light absorption, carrier separation and migration, and surface reaction. Finally, based on the above understanding, perspectives and opportunities about defective materials are considered for various photocatalytic applications.

17.
Electrophoresis ; 30(4): 668-73, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19180545

RESUMEN

An MEKC method combining field-amplified sample injection (FASI) has been developed for the analysis of albumin (Alb) and transferrin (TRF) in human urines. Various parameters affecting FASI preconcentration were optimized systematically. Under the optimum conditions, using electrokinetic sample injection for 90 s, the sensitivity was improved 77.6- and 45.3-fold for TRF and Alb, respectively, without loss of separation efficiency when compared with hydrodynamical sample injection for 5 s (0.5 psi). The detection limits of TRF and Alb were found to be 0.31 and 0.14 mg/L, respectively. The proposed method has been successfully applied to the determination of TRF and Alb in desalted urines from patients with kidney diseases, and the recoveries of TRF and Alb were 91.1-101.7%.


Asunto(s)
Albúminas/aislamiento & purificación , Albuminuria , Cromatografía Capilar Electrocinética Micelar/métodos , Transferrina/orina , Acetonitrilos/química , Humanos , Enfermedades Renales/metabolismo , Sensibilidad y Especificidad , Cloruro de Sodio/química , Solventes/química , Transferrina/aislamiento & purificación , Ácido Trifluoroacético/química , Agua/química
18.
Cancer Med ; 8(18): 7774-7780, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31670906

RESUMEN

BACKGROUND: Cervical cancer is one of the most common causes of cancer-associated mortality among affected women in the world. At present, treatment with weekly cisplatin plus ionizing radiation (IR) therapy is the standard regimen for cervical cancer, especially for locally advanced cervical cancer. The purpose of this study is to determine whether FEN1 inhibitors could enhance the therapeutic effect of IR therapy. METHODS: Western blot was applied to determine the expression of FEN1- and apoptosis-related proteins. Cell growth inhibition assay and colony formation assay were used to determine the effects of FEN1 inhibitor and IR exposure for Hela cells in vitro. CRISPR technology was used to knockdown FEN1 expression level of 293T cells, and tumor xenograft in nude mice was employed to determine the effects of FEN1 inhibitor and IR exposure on tumor growth in vivo. RESULTS: Our data revealed that FEN1 is overexpressed in HeLa cell and can be upregulated further by IR. We also demonstrated that FEN1 inhibitor enhances IR sensitivity of cervical cancer in vitro and in vivo. CONCLUSION: FEN1 inhibitor SC13 could sensitize radiotherapy of cervical cancer cell.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Endonucleasas de ADN Solapado/antagonistas & inhibidores , Tolerancia a Radiación/efectos de los fármacos , Fármacos Sensibilizantes a Radiaciones/farmacología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Modelos Animales de Enfermedad , Femenino , Endonucleasas de ADN Solapado/genética , Endonucleasas de ADN Solapado/metabolismo , Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , Células HeLa , Humanos , Ratones , Radiación Ionizante , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patología , Ensayos Antitumor por Modelo de Xenoinjerto
19.
J Sep Sci ; 31(5): 865-71, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18348329

RESUMEN

A method has been developed for the determination of triptonide in the traditional Chinese herb Tripterygium wilfordii Hook F. by micellar electrokinetic capillary chromatography combined with cloud point extraction. The analyte was extracted at pH 3.0 by micelles of the nonionic surfactant polyoxyethylene 7,5-octylphenyl ether (Triton X-114). A 250-muL aliquot from the extracted surfactant-rich phase was diluted to 400 muL with ethanol to reduce its viscosity before separation by MEKC. Under optimum conditions, an enrichment factor of 25 is obtained and the determination limit of triptonide is found to be 3.15 x 10(-7) mol/L. The proposed method has been successfully applied to the determination of triptonide in T. wilfordii tablet and spiked urine matrix, demonstrating the feasibility and reliability of the proposed method.


Asunto(s)
Cromatografía Capilar Electrocinética Micelar/métodos , Tripterygium/química , Triterpenos/análisis , Estudios de Factibilidad , Humanos , Concentración de Iones de Hidrógeno , Estructura Molecular , Reproducibilidad de los Resultados , Tensoactivos/química , Temperatura , Triterpenos/química , Triterpenos/orina , Viscosidad
20.
Nucl Med Commun ; 29(3): 230-8, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18349793

RESUMEN

OBJECTIVE: To evaluate the myocardial ischaemia/viability in patients with acute myocardial infarction (AMI) using the ischaemia-avid agent (99m)Tc-HL91. METHODS: Thirty-three AMI patients received 740 MBq (20 mCi) (99m)Tc-HL91, i.v., first and then 148-185 MBq (4-5 mCi) (201)Tl around 3 h later. The patient underwent initial imaging and 24 h late imaging, 10-15 min and 24 h later, respectively, after intravenous injection of (201)Tl. Myocardial segmental radioactive counts of (99m)Tc-HL91 were quantified by the region of interest technique. The segmental radioactive counts/pixel divided by those of the corresponding left ventricular cavities were ratios, which were compared among normal, ischemic/viable and fixed defect myocardium. The correlation analysis between the segmental scores from (201)Tl imaging and the ratios was performed. RESULTS: The cross-talk of (99m)Tc into (201)Tl could be neglected in the present study. Out of the 33 AMI patients, the (99m)Tc-HL91 image quality analysis classified seven cases into excellent, accounting for 21%, eight cases into good, for 24%, eight cases into fair, for 24%, and 10 cases into poor, for 31%. The ratios were 1.16 (1.01, 1.35) ((median (25th to 75th percentile)), 1.15, 0.20 and 1.01 (0.86, 1.30), respectively, in normal, ischaemic/viable and fixed defect myocardium. Significant differences (chi2=17.2069, P=0.0002) were found in the ratios. The ratios of the ischaemic/viable myocardial segments were significantly higher than those of the fixed defect segments. Unexpectedly, the normal myocardial segments took up (99m)Tc-HL91, too, even slightly higher than the ischaemic/viable myocardial segments. CONCLUSIONS: Myocardial uptake of (99m)Tc-HL91 is perfusion-dependent as well as ischaemia dependent. (99m)Tc-HL91 hypoxia imaging alone is not sufficient to identify ischaemic/viable myocardium. Dual-isotope imaging with (201)Tl and (99m)Tc-HL91 can characterize the myocardium into normal, ischaemic/viable and necrotic (scarred) myocardium.


Asunto(s)
Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Infarto del Miocardio/diagnóstico por imagen , Compuestos de Organotecnecio , Oximas , Talio , Anciano , Hipoxia de la Célula , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cintigrafía , Radiofármacos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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