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1.
J Thorac Imaging ; 39(2): 101-110, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37265250

RESUMEN

PURPOSE: The purpose of this study was to investigate the effect of integrated evaluation of resting static computed tomography perfusion (CTP) and coronary computed tomography angiography (CCTA)-derived fractional flow reserve (FFR CT ) on therapeutic decision-making and predicting major adverse cardiovascular events (MACEs) in patients with suspected coronary artery disease. MATERIALS AND METHODS: In this post hoc analysis of a prospective trial of CCTA in patients assigned to either CCTA or CCTA plus FFR CT arms, 500 patients in the CCTA plus FFR CT arm were analyzed. Both resting static CTP and FFR CT were evaluated by using the conventional CCTA. Perfusion defects in the myocardial segments with ≥50% degree of stenosis in the supplying vessels were defined as resting static CTP positive, and any vessel with an FFR CT value of ≤0.80 was considered positive. Patients were divided into 3 groups: (1) negative CTP-FFR CT match group (resting static CTP-negative and FFR CT -negative group); (2) mismatch CTP-FFR CT group (resting static CTP-positive and FFR CT -negative or resting static CTP-negative and FFR CT -positive group); and (3) positive CTP-FFR CT match group (resting static CTP-positive and FFR CT -positive group). We compared the revascularization-to-invasive coronary angiography ratio and the MACE rate among 3 subgroups at 1- and 3-year follow-ups. The adjusted Cox hazard proportional model was used to assess the prognostic value of FFR CT and resting static CTP to determine patients at risk of MACE. RESULTS: Patients in the positive CTP-FFR CT match group were more likely to undergo revascularization at the time of invasive coronary angiography compared with those in the mismatch CTP-FFR CT group (81.4% vs 57.7%, P =0.033) and the negative CTP-FFR CT match group (81.4% vs 33.3%, P= 0.001). At 1- and 3-year follow-ups, patients in the positive CTP-FFR CT match group were more likely to have MACE than those in the mismatch CTP-FFR CT group (10.5% vs 4.2%, P= 0.046; 35.6% vs 9.4%, P <0.001) and the negative CTP-FFR CT match group (10.5% vs 0.9%, P <0.001; 35.6% vs 5.4%, P <0.001). A positive CTP-FFR CT match was strongly related to MACE at 1-year (hazard ratio=8.06, P= 0.003) and 3-year (hazard ratio=6.23, P <0.001) follow-ups. CONCLUSION: In patients with suspected coronary artery disease, the combination of FFR CT with resting static CTP could guide therapeutic decisions and have a better prognosis with fewer MACE in a real-world scenario.


Asunto(s)
Enfermedad de la Arteria Coronaria , Estenosis Coronaria , Reserva del Flujo Fraccional Miocárdico , Imagen de Perfusión Miocárdica , Humanos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/terapia , Imagen de Perfusión Miocárdica/métodos , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Tomografía Computarizada por Rayos X/métodos , Ensayos Clínicos como Asunto
2.
Dose Response ; 17(1): 1559325819828623, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30944552

RESUMEN

The study aimed to develop a novel dose conversion platform by improving linear-quadratic (LQ) model to more accurately describe radiation response for high fraction/acute doses. This article modified the LQ model via piecewise fitting the biological dose curve using different fractionated dose and optimizing the consistency between mathematical model and experimental data to gain a more reasonable transform. That mathematical development of the LQ model further amended certain deviations of various cell curves with high doses and implied the rationality of the present model at low dose range. The modified biologically effective dose model that solved the dilemma of inaccurate LQ model had been used in comparing between hypofractionated and conventional fractioned dose. It has been verified that the calculated values are similar in the treatment of same efficacy, no matter what α/ß is, and provided a more rational explanation for significant differences among various hypofractionations. The equivalent uniform dose based on the subsection function could represent arbitrary inhomogeneous dose distributions including high-dose fractions, providing a foundation for the implementation of detailed evaluation of different cell dose effects.

3.
J Radiat Res ; 55(4): 794-802, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24614820

RESUMEN

The purpose of this study was to analyze the clinical outcomes of simultaneous modulated accelerated radiotherapy (SMART) in patients with nasopharyngeal carcinoma (NPC). A total of 97 patients who underwent SMART for NPC between August 2005 and November 2011 were evaluated. The prescribed dose was 69.9 Gy/30 fractions at 2.33 Gy/fraction to the primary gross tumor volume (PGTV) including the nasopharynx gross target volume and the positive neck lymph nodes, and 60 Gy/30 fraction at 2.0 Gy/fraction to the PCTV1; 54 Gy/30 fractions at 1.8 Gy/fraction was given to the PCTV2. Among 59 patients with local advanced disease, 31 patients received concurrent chemoradiotherapy (chemo-RT) with a regimen consisting of 135 mg/m(2) paclitaxel on Day 1 and 25 mg/m(2) cisplatin on Days 1-3. The median follow-up period was 42 months. The local control rate (LCR), distant metastases-free survival (DMFS) and overall survival (OS) rates were 93.3%, 90.3% and 91.6% at 3 years, and 87.6%, 87.9% and 85.7% at 5 years, respectively. There was no significant difference in outcome with respect to these three indicators for Stage III and IV disease treated with/without concurrent chemoradiotherapy (P > 0.05). Acute toxicities included Grade 3 mucositis, skin desquamation, and leucopenia, which occurred in 78 (80.4%), 8 (8.2%), and 45 (46.4%) patients, respectively. No patient had a Grade 3-4 late toxicity. SMART was associated with a favorable outcome for NPC with acceptable toxicity. The local-regional control was excellent but distant metastasis remains the main risk. The combination of SMART and chemotherapy needs to be optimized through further studies to enhance outcomes for locally advanced diseases.


Asunto(s)
Neoplasias Nasofaríngeas/radioterapia , Radioterapia de Intensidad Modulada/métodos , Adolescente , Adulto , Anciano , Carcinoma , Quimioradioterapia , Niño , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/tratamiento farmacológico , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada/efectos adversos , Adulto Joven
4.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 6): o1329, 2009 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-21583183

RESUMEN

In the title compound, C(8)H(12)N(2)·H(2)O, four substituted pyridine mol-ecules alternate with four water mol-ecules, forming a large ring via O(water)-H⋯N(pyridine) and N(amine)-H⋯O(water) hydrogen bonding. Adjacent rings are connected via O(water)-H⋯O(water) hydrogen-bonds, forming a three-dimensional network.

5.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 8): o1653, 2008 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-21203339

RESUMEN

(RS)-(±)-2-Methoxy-carbonyl-3-tropinone is an important inter-mediate for the preparation of cocaine and its derivatives. The molecule in the title compound, C(10)H(16)NO(3) (+)·C(4)H(5)O(6) (-), is present as the enol tautomer. The six-membered ring adopts a half boat conformation, and the five-membered ring a slightly distorted envelope conformation. There are intra- and inter-molecular hydrogen bonds involving the hydroxyl, carboxyl groups and quaternary ammonium groups.

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