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1.
Microsyst Nanoeng ; 10: 13, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38259520

RESUMEN

This study introduces a novel image capture and lighting techniques using a cutting-edge hybrid MEMS scanner system designed for compact microscopic imaging. The scanner comprises a tapered optical fiber waveguide and innovative aerosol-jet printed PZT (lead zirconate titanate) bimorph push-pull actuators on a stainless-steel substrate, effectively addressing issues that are commonly associated with PZT on silicon substrates such as fracture and layer separation. By leveraging nonlinear vibration, the scanner achieves a spiral scan pattern from a single signal input, in addition to the expected two-dimensional scanning and target illumination from two phase-shifted inputs. This capability is further enhanced by a novel process to taper the optical fiber, which reduces illumination scattering and tunes the fiber to the resonant frequencies of the scanner. The precisely tapered tip enables large fields of view while maintaining independent 2-axis scanning through one-degree-of-freedom actuation. Experimental validation showcases the successful generation of a spiral scan pattern with a 60 µm diameter scan area and a 10 Hz frame rate, effectively reconstructing scanned images of 5 µm lines, cross patterns (15 µm in length with a 5 µm gap), and structures of a Psychodidae wing.

2.
Front Public Health ; 10: 836914, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35903385

RESUMEN

Background: The association between sex and the survival of patients with esophageal cancer (EC) remains controversial. We sought to systematically investigate sex-based disparities in EC survival using the Surveillance, Epidemiology, and End Results (SEER) registry data from the United States. Methods: Patients with EC diagnosed from 2004 to 2015 registered in the SEER database were selected. The association between sex and cancer-specific survival (CSS) was evaluated using survival analysis. The Inverse Probability Weighting (IPW) approach was applied to reduce the observed bias between males and females. Subgroup analyses were used to investigate the robustness of the sex-based disparity and to explore potential interaction effects with other variables. Results: Overall, 29,312 eligible EC patients were analyzed, of whom 5,781 were females, and 23,531 were males. Females had higher crude CSS compared to males (10-year CSS: 24.5 vs. 21.3%; P < 0.001). Similar results were obtained after adjusting for selection bias using the IPW approach and multivariate regression. Subgroup analyses confirmed the relative robustness of sex as a prognostic factor. However, significant interactions were observed between sex and other variables, such as age, race, tumor grade, histology, and treatment modality. In particular, there was no survival advantage for premenopausal females compared to their male counterparts, but the association between sex and EC survival was prominent in 46-55-year-old patients. Conclusions: Female EC patients had better long-term survival than males. The association between sex and EC survival vary according to age, race, tumor grade, histology, and treatment modality. Sex-based disparity in EC-specific survival was age-related in the United States population.


Asunto(s)
Neoplasias Esofágicas , Neoplasias Esofágicas/epidemiología , Neoplasias Esofágicas/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Programa de VERF , Análisis de Supervivencia , Estados Unidos/epidemiología
3.
Oral Oncol ; 117: 105284, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33845238

RESUMEN

OBJECTIVES: Chemoradiotherapy is the standard treatment for locoregionally advanced nasopharyngeal carcinoma (NPC). We aimed to reveal factors associated with chemotherapy use and evaluate chemotherapy's benefit in patients with stage III NPC stratified by lymph node status. PATIENTS AND METHODS: Overall, 1452 patients with stage III NPC who underwent radiotherapy with (n = 1361) or without (n = 91) chemotherapy were identified in the SEER database. We examined predictors for chemotherapy use using logistic regression analysis. We compared all-cause mortality (ACM) and cancer-specific mortality (CSM) using the Kaplan-Meier method. Cox regression and competing risk analyses were used to evaluate the benefit of chemotherapy. The inverse probability of treatment weighting (IPTW) approach was applied to reduce selection bias and adjust for competing risks. Subgroup analyses and interaction effects were explored. RESULTS: Factors including age, sex, insured status, tumor grade, and N category were associated with chemotherapy use. Chemotherapy was associated with decreased 5-year ACM (31.4% vs. 48.4%, p < 0.001) and CSM (25.5% vs. 35.8%; p = 0.017) in stage III NPC patients. The IPTW-adjusted hazard ratio for 5-year ACM was 0.57 (95% CI: 0.38-0.86, p = 0.008), whereas IPTW-adjusted sub-hazard ratio for 5-year CSM was 0.62 (95% CI: 0.42-0.93, p = 0.003). A significant interaction effect existed between lymph node status and treatment modality. Chemotherapy offered a significant survival benefit in node-positive stage III NPC. However, no chemotherapy benefit for the node-negative disease was observed. CONCLUSION: Chemotherapy adds survival benefit in stage III NPC, especially in patients with node-positive disease. The magnitude of chemotherapy benefit in node-negative stage III NPC warrants further investigation.


Asunto(s)
Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Quimioradioterapia , Bases de Datos Factuales , Humanos , Carcinoma Nasofaríngeo/tratamiento farmacológico , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/radioterapia , Estadificación de Neoplasias , Estudios Retrospectivos , Programa de VERF
4.
J Mol Model ; 26(4): 69, 2020 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-32146567

RESUMEN

Based on molecular dynamics (MD) simulation, the binding energy, cohesive energy density (CED), bond length, and mechanical parameters were calculated for 2,6-diamino-3,5-dinitropyrazine-l-oxide (LLM-105) crystal, octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) crystal, and their co-crystals under different temperatures. Three LLM-105/HMX patterns were constructed to investigate the influence of component proportion on structures and properties of co-crystals, in which the mole ratios of LLM-105 and HMX are 1:1, 1:2, and 2:1. The effect of temperature and components on the stability and sensitivity were investigated as well. The results show that the binding energies, CED and mechanical parameters of all the co-crystals, decrease when the temperature increases from 248 to 398 K, while their maximum N-NO2 bond length (Lmax) increases with rising temperature, indicating that the sensitivities increase and stabilities decrease when temperature rises. At all temperatures, co-crystals exhibit larger CED and shorter bond length than that of single explosive, demonstrating that they are more stable and less sensitive than single crystal, where the stability of co-crystals was ordered as 2:1>1:1>1:2. Moreover, the bulk modulus (K) and shear modulus (G) of co-crystals are lower than that of HMX, conversely, the Cauchy pressure and K/G are higher than that of HMX, implying co-crystals have better ductility. Finally, the 2:1 ratio of LLM-105/HMX co-crystal was identified as the excellent one, owning to the highest binding energy, highest CED, shortest Lmax, and greatest ductility. Graphical Abstract Models of LLM-105/HMX and one of the properties.

5.
Ann N Y Acad Sci ; 1375(1): 52-65, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27447538

RESUMEN

Hepatic iron accumulation may be responsible for the pathology of nonalcoholic fatty liver disease (NAFLD), which is both increasingly prevalent in conjunction with obesity and associated with comorbidities. The efficacy of iron reduction therapies, such as phlebotomy or dietary iron restriction, has been demonstrated in patient and animal models, including models of diabetes and obesity; however, the effects on and exact mechanisms responsible for iron depletion in NAFLD have not been clearly elucidated. Our study investigated the role of iron depletion by deferoxamine (DFO) treatment of ob/ob mice with hepatic steatosis. We found that DFO reduced hepatic iron deposition and regulated intracellular iron concentration in a homeostatic process following 15 days of treatment. Compared with vehicle treatment, DFO significantly improved hepatic steatosis by upregulating proteins related to lipid metabolism. Meanwhile, the reduction of free radical formation and proinflammatory cytokines, as well as the increase of hypoxia-inducible factor-1α pathway proteins and Bcl2/Bax ratio, further indicated that DFO was effective for liver protection and hepatic adaptation. These findings show that the intraperitoneal delivery of DFO provides a potential means of both preventing the progression of NAFLD and accelerating healing of hepatic steatosis, with the potential for rapid clinical application.


Asunto(s)
Deferoxamina/uso terapéutico , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Animales , Proteínas Reguladoras de la Apoptosis/metabolismo , Peso Corporal/efectos de los fármacos , Deferoxamina/farmacología , Conducta Alimentaria/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Inflamación/patología , Espacio Intracelular/metabolismo , Hierro/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Ratones Obesos , Enfermedad del Hígado Graso no Alcohólico/sangre , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Tamaño de los Órganos/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos
6.
Head Neck ; 33(1): 87-94, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20848421

RESUMEN

BACKGROUND: A meta-analysis was conducted to evaluate the accuracy of whole-body positron emission tomography (PET) and PET-CT in initial M staging of head and neck cancer. METHODS: After a systematic review of English language studies, sensitivity, specificity, and other measures of whole-body PET and PET-CT were pooled. Summary receiver operating characteristic (SROC) curves were also used to summarize overall test performance. RESULTS: Eight PET and 7 PET-CT studies were identified. The pooled sensitivity estimates for PET and PET-CT were 0.848 (95% confidence interval [CI], 0.776-0.905) and 0.875 (95% CI, 0.787-0.936). The pooled specificity estimates were 0.952 (95% CI, 0.933-0.967) and 0.950 (95% CI, 0.931-0.964). The Q* index estimates for PET-CT (0.9409) were not significantly higher than for PET (0.9154; p > .05). CONCLUSION: Whole-body PET and PET-CT have good diagnostic performance in initial M staging of head and neck cancer; although PET-CT tends to have higher accuracy than PET.


Asunto(s)
Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/patología , Estadificación de Neoplasias/métodos , Tomografía de Emisión de Positrones/métodos , Imagen de Cuerpo Entero , Femenino , Humanos , Masculino , Intensificación de Imagen Radiográfica , Radiofármacos , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X/métodos
7.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-325106

RESUMEN

<p><b>OBJECTIVE</b>To summarize the anesthetic management in fetal lamb cardiac bypass.</p><p><b>METHODS</b>Five ewes at 120-140 days of gestation were anesthetized intramuscularly with katamine hydrochloride, intubated and ventilated with a respirator. Anesthesia was maintained with fentanyl and vecuronium. Lactated Ringer's solution and magnesium sulfate were infused to maintain the mean blood pressure (MAP) over 70 mmHg and uterine relaxation. The fetal lambs received anesthesia with fentanyl and vecuronium intramuscularly via the uterine wall. Fetal cardiac bypass was established with pulmonary artery and right atrium cannulation, lasting for 30 min. The hemodynamic and blood gas data of the ewes and fetal lambs were recorded before bypass, at 30 min during bypass, and at 1 and 2 h after cessation of bypass. The pulse index of the umbilical artery (PIua) and the ewe's uterine artery (PIeu) were monitored simultaneously.</p><p><b>RESULTS</b>The MAP and heart rate (HR) of the fetus remained normal during the anesthesia. PIua increased significantly after cessation of bypass (P<0.05). Although the fetal oxygen tension in the axillary artery remained normal, the fetal lambs showed hypercarbia and acidosis after cessation of bypass (P<0.05). The maternal MAP and HR remained normal. The PIeu decreased significantly during bypass (P<0.05) and recovered the normal level after cessation of bypass. The arterial blood gas of the ewes was normal during the experiment.</p><p><b>CONCLUSION</b>Maintaining high hemodynamics in the ewes, application of uterine relaxation and intensive care during anesthesia are crucial in anesthetic management of cardiac bypass in fetal lambs.</p>


Asunto(s)
Animales , Femenino , Embarazo , Anestésicos Disociativos , Puente Cardiopulmonar , Métodos , Fentanilo , Corazón Fetal , Cirugía General , Cabras , Cirugía General , Ketamina , Bromuro de Vecuronio
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