RESUMEN
We study the driven dynamics across the critical points of the Yang-Lee edge singularities (YLESs) in a finite-size quantum Ising chain with an imaginary symmetry-breaking field. In contrast to the conventional classical or quantum phase transitions, these phase transitions are induced by tuning the strength of the dissipation in a non-Hermitian system and can occur even at finite size. For conventional phase transitions, universal behaviors in driven dynamics across critical points are usually described by the Kibble-Zurek mechanism, which states that the scaling in dynamics is dictated by the critical exponents associated with one critical point and topological defects will emerge after the quench. While the mechanism leading to topological defects breaks down in the YLES, we find that for small lattice size, the driven dynamics can still be described by the Kibble-Zurek scaling with the exponents determined by the (0+1)-dimensional YLES. For medium finite size, however, the driven dynamics can be described by the Kibble-Zurek scaling with two sets of critical exponents determined by both the (0+1)-dimensional and the (1+1)-dimensional YLESs.
RESUMEN
Currently, robotic-assisted coronary artery bypass grafting (RACABG) is a feasible choice for myocardial revascularization. Acceptable outcomes have been reported for RACABG with single target vessels; however, the long-term benefits of multivessel RACABG with composite arterial grafts have rarely been studied. Therefore, our study investigated the long-term results of multivessel RACABG with composite arterial grafts by reviewing the clinical data of patients from Taichung Veterans General Hospital. From December 2005 to June 2015, 562 patients underwent robotic-assisted robotic minimally invasive direct coronary bypass (MIDCAB) at Taichung Veterans General Hospital. Two major composite arterial graft configurations (i.e., inverted T-graft and Y-graft) were used. Data regarding the short-term and long-term outcomes of robotic-assisted MIDCAB were obtained from the medical records. For data regarding long-term outcomes of the patients not followed up at our institution, telephone interviews were conducted in June 2019. The in-hospital mortality rate and complication rate were 2.5% and 17.6%, respectively. We completed the follow-up for 486 patients (86.4%), and postoperative coronary imaging-based evaluation performed for 157 patients. The 5-year and 10-year survival rates were 82.7% and 65.2%, respectively. The 5-year and 10-year major adverse cardiac and cerebral events-free survival rates were 86.9% and 70.9%, respectively. The 5-year patency rate of various coronary anastomoses was 85.1-100%. Our study revealed that multivessel robotic-assisted MIDCAB with composite arterial grafts provided acceptable long-term outcomes, irrespective of the composite graft configuration.
Asunto(s)
Procedimientos Quirúrgicos Robotizados , Robótica , Humanos , Procedimientos Quirúrgicos Robotizados/métodos , Angiografía Coronaria/métodos , Puente de Arteria Coronaria , Resultado del Tratamiento , Estudios RetrospectivosRESUMEN
The association between a high-fat diet and breast cancer risk is controversial. We hypothesized that the exposure of rats to a high-fat diet in utero via the maternal diet would result in a greater risk of carcinogen-induced mammary tumors than high-fat diet exposure in postnatal life. Rats were exposed to a high-fat diet with 40% of the energy source as safflower oil in utero (In utero group), at postnatal days 30-50 (Puberty group), postnatal days 150-170 (Adult group), postnatal days 1-230 (Postnatal group) or for their whole life from in utero (Whole group). Chow diet-fed rats were used as the Nonexposure group. Mammary tumor incidence was significantly higher in the In utero (60%), Postnatal (61%) and Whole (91%) groups than in the Nonexposure group (32%), but there was no significant difference between the Puberty (44%), Adult (44%) and Nonexposure groups. Arachidonic acid levels were 10 times higher in mammary tumor tissue than in the normal mammary gland across all groups and were positively correlated with tumor weight. We conclude that the timing, but not the duration, of high-fat diet exposure makes rats more susceptible to carcinogen-induced mammary tumors and that exposure in utero to a maternal high-fat diet during pregnancy is more important in increasing the risk of mammary tumors in the female offspring than exposure of the offspring to the same high-fat diet later in life.
Asunto(s)
9,10-Dimetil-1,2-benzantraceno/toxicidad , Carcinógenos/toxicidad , Grasas de la Dieta/administración & dosificación , Neoplasias Mamarias Animales/inducido químicamente , Complicaciones Neoplásicas del Embarazo/patología , Animales , Peso Corporal , Estradiol/sangre , Femenino , Lípidos/análisis , Neoplasias Mamarias Animales/patología , Embarazo , Preñez , Efectos Tardíos de la Exposición Prenatal , Ratas , Ratas Sprague-Dawley , Factores de RiesgoRESUMEN
BACKGROUND: Damage of tricuspid valve (TV) with resultant tricuspid regurgitation (TR) induced by endomyocardial biopsy (EMB) following heart transplantation has been reported in several studies. This study tried to determine the prevalence of EMB-related iatrogenic damage over tricuspid apparatus following orthotopic heart transplantation and to evaluate its impact on the patients. METHODS: Fifty patients received orthotopic heart transplantation between July 1987 and March 2005. Eleven patients were excluded from the study due to early postoperative mortality or inadequate follow-up. The medical records of the remaining 39 patients were reviewed retrospectively for basic characteristics as well as each attempted EMB. The iatrogenic damage of tricuspid apparatus and serial change of TR were accessed with 2-D and Doppler echocardiography. The obtained data were analyzed for their statistical significance with SPSS (version 12.0). RESULTS: A total of 373 biopsies were performed on the 39 patients between 1987 and 2005. The follow-up duration was 42.9+/-26.7 months. The prevalence of TR immediately following heart transplantation was 84.6%, with only 25.6% of patients having moderate or severe TR. At the end of the follow-up, the prevalence of TR increased to 92.3% and 61.5% of patients having moderate or severe TR, respectively. Eight patients (20.5%) had small chordae rupture (SCR) noted after 6.6+/-3.2 biopsies, and 10 patients (25.6%) had flail tricuspid valve (FTV) after 5.7+/-5.1 biopsies. Of patients with SCR, 62.5% had progression of TR, and 70% of patients with FTV showed significant TR change. CONCLUSION: The prevalence of iatrogenic tricuspid apparatus damage was high in this study. It contributed to the progression of TR significantly regardless of the damage severity. Measurements should be taken for prevention of iatrogenic tricuspid apparatus damage induced by EMB.
Asunto(s)
Biopsia/efectos adversos , Miocardio/patología , Insuficiencia de la Válvula Tricúspide/etiología , Adulto , Anciano , Femenino , Trasplante de Corazón/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Insuficiencia de la Válvula Tricúspide/cirugíaRESUMEN
A left atrial mass associated with coronary artery disease is often diagnosed as a mural thrombus rather than other possible etiologies such as benign primary cardiac tumor (myxoma, lipoma), a malignant primary cardiac tumor (sarcoma, lymphoma), or secondary involvement for extracardiac tumors. Malignant lymphoma initially presenting as intracardiac masses is very rare. Chest computed tomography with contrast enhancement and cardiac magnetic resonance may be the best methods for distinguishing primary cardiac tumors from direct extension from adjacent mediastinal structures. We report the case of a 59-year-old man with incidentally found mediastinal diffuse large B-cell lymphoma invading the left atrium, which presented with coronary artery disease and a left atrial mass. Improvement in cardiac ventricular function heart after coronary artery bypass grafting may provide the patient with a better chance of receiving an adequate dose of chemotherapy.