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1.
Phys Rev Lett ; 132(3): 036502, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38307085

RESUMEN

The recently discovered nickelate superconductor La_{3}Ni_{2}O_{7} has a high transition temperature near 80 K under pressure, providing an additional avenue for exploring unconventional superconductivity. Here, with state-of-the-art tensor-network methods, we study a bilayer t-J-J_{⊥} model for La_{3}Ni_{2}O_{7} and find a robust s-wave superconductive (SC) order mediated by interlayer magnetic couplings. Large-scale density matrix renormalization group calculations find algebraic pairing correlations with Luttinger parameter K_{SC}≲1. Infinite projected entangled-pair state method obtains a nonzero SC order directly in the thermodynamic limit, and estimates a strong pairing strength Δ[over ¯]_{z}∼O(0.1). Tangent-space tensor renormalization group simulations elucidate the temperature evolution of SC pairing and further determine a high SC temperature T_{c}^{*}/J∼O(0.1). Because of the intriguing orbital selective behaviors and strong Hund's rule coupling in the compound, t-J-J_{⊥} model has strong interlayer spin exchange (while negligible interlayer hopping), which greatly enhances the SC pairing in the bilayer system. Such a magnetically mediated pairing has also been observed recently in the optical lattice of ultracold atoms. Our accurate and comprehensive tensor-network calculations reveal a robust SC order in the bilayer t-J-J_{⊥} model and shed light on the pairing mechanism of the high-T_{c} nickelate superconductor.

2.
Artículo en Inglés | MEDLINE | ID: mdl-29715446

RESUMEN

Available online April 7, 2018. This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

3.
Head Neck ; 41(4): 915-923, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30758110

RESUMEN

BACKGROUND: The clinical degradation rate and strength of biodegradable implant exposed to postoperative radiotherapy (PORT) are unknown. METHODS: A prospective randomized control trial of 40 consecutive mandibulotomy patients randomly divided into titanium and biodegradable cohorts. All patients received PORT. The following parameters were compared: maximal mouth opening, occlusal force, center of force trajectory, occlusal status, radiographic evidence of bony union, mandibular function impairment questionnaire (MFIQ), overall satisfaction score, and complication rates. RESULTS: Both the mandibular function and occlusal status parameter of the biodegradable and the titanium groups were not significantly difference. Biodegradable cohort showed better MFIQ scores (P = .08) and overall satisfaction scores (P = .64) but was not statistically significant. Of note, 40% of patients in the titanium cohort complained of plate palpability/cold intolerance and required plate removal (P = .02); 10% of patients in the titanium cohort developed osteoradionecrosis. CONCLUSION: Biodegradable osteosynthesis is as reliable as titanium osteosynthesis for mandibulotomy fixation. PORT did not increase the complication rate in the biodegradable group.


Asunto(s)
Implantes Absorbibles , Carcinoma de Células Escamosas/patología , Osteotomía Mandibular/métodos , Titanio/uso terapéutico , Neoplasias de la Lengua/patología , Anciano , Carcinoma de Células Escamosas/cirugía , Femenino , Estudios de Seguimiento , Fijación Interna de Fracturas/métodos , Curación de Fractura/fisiología , Humanos , Masculino , Fracturas Mandibulares/diagnóstico por imagen , Fracturas Mandibulares/cirugía , Neoplasias Mandibulares/secundario , Neoplasias Mandibulares/cirugía , Persona de Mediana Edad , Estudios Prospectivos , Medición de Riesgo , Estadísticas no Paramétricas , Neoplasias de la Lengua/cirugía , Resultado del Tratamiento
4.
Head Neck ; 41(9): 3168-3176, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31136050

RESUMEN

BACKGROUND: Computer-aided design/computer-aided manufacturing (CAD/CAM) surgical templates allow precise mandibular reconstructive surgery. However, their clinical accuracy is limited by manual plate bending. Digitally hydroformed plates maintain a digital workstream in virtual planning. METHODS: Twelve patients with Brown's class IIc mandibular defects were randomized into two groups: group I (experimental), the reconstruction plate was digitally hydroformed, and group II (control), surgeries were performed CAD/CAM guided with the reconstruction plate manually prebent. The linear and angular deviations of reconstruction outcomes were compared to surgical simulation in both groups. RESULTS: The mean linear and angular deviations of middle and posterior segments were 2.14 ± 0.79 mm, 3.71 ± 0.95 mm, 8.73° ± 1.91°, and 9.06° ± 0.96° in group I and 4.31 ± 0.78 mm, 6.74 ± 1.40 mm, 16.35° ± 0.72°, and 31.48° ± 3.38° in group II, respectively. Measurements in group I were significantly lower than group II (P < .005). CONCLUSION: Digital hydroforming for plate prebent is a reliable method that helps improving the clinical accuracy of CAD/CAM-guided mandibular reconstruction surgery.


Asunto(s)
Placas Óseas , Diseño Asistido por Computadora , Cóndilo Mandibular/cirugía , Reconstrucción Mandibular/instrumentación , Diseño de Prótesis/métodos , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Reconstrucción Mandibular/métodos , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
5.
Clinics (Sao Paulo) ; 71(10): 575-579, 2016 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-27759845

RESUMEN

OBJECTIVES:: This study aimed to evaluate the stability of prostheses supported by zygoma implants and remaining teeth for subjects who had undergone hemi-maxillectomy. METHODS:: Ten patients were included in the study. Oral rehabilitation was performed using a temporary prosthesis that was supported by remaining teeth for the first three months. Then, a zygoma implant was placed to provide support for a final prosthesis in addition to the remaining teeth. Each prosthesis was tailor-made according to biomechanical three-dimensional finite element analysis results. The patients were assessed using the prosthesis functioning scale of the Memorial Sloan-Kettering Cancer Center. In addition, retention and bite force were recorded for both the temporary prosthesis and the final prosthesis. RESULTS:: The mean bite force of the prosthetic first molar was increased to 69.2 N. The mean retentive force increased to 13.5 N after zygoma implant insertion. The bite force on the prosthetic first molar was improved to 229.3 N. CONCLUSION:: Bite force increased significantly with the support of a zygoma implant. The use of zygoma implants in the restoration of maxillary defects improved functional outcome and patient satisfaction.


Asunto(s)
Prótesis Dental de Soporte Implantado/métodos , Maxilar/cirugía , Cigoma/cirugía , Adulto , Anciano , Fuerza de la Mordida , Carcinoma de Células Escamosas/cirugía , Diseño de Prótesis Dental , Femenino , Análisis de Elementos Finitos , Humanos , Masculino , Reconstrucción Mandibular , Neoplasias Maxilares/cirugía , Persona de Mediana Edad , Rehabilitación Bucal/métodos , Osteosarcoma/cirugía , Satisfacción del Paciente , Periodo Posoperatorio , Reproducibilidad de los Resultados , Estudios Retrospectivos , Resultado del Tratamiento
6.
Clinics ; 71(10): 575-579, Oct. 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-796868

RESUMEN

OBJECTIVES: This study aimed to evaluate the stability of prostheses supported by zygoma implants and remaining teeth for subjects who had undergone hemi-maxillectomy. METHODS: Ten patients were included in the study. Oral rehabilitation was performed using a temporary prosthesis that was supported by remaining teeth for the first three months. Then, a zygoma implant was placed to provide support for a final prosthesis in addition to the remaining teeth. Each prosthesis was tailor-made according to biomechanical three-dimensional finite element analysis results. The patients were assessed using the prosthesis functioning scale of the Memorial Sloan-Kettering Cancer Center. In addition, retention and bite force were recorded for both the temporary prosthesis and the final prosthesis. RESULTS: The mean bite force of the prosthetic first molar was increased to 69.2 N. The mean retentive force increased to 13.5 N after zygoma implant insertion. The bite force on the prosthetic first molar was improved to 229.3 N. CONCLUSION: Bite force increased significantly with the support of a zygoma implant. The use of zygoma implants in the restoration of maxillary defects improved functional outcome and patient satisfaction.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Prótesis Dental de Soporte Implantado/métodos , Maxilar/cirugía , Cigoma/cirugía , Fuerza de la Mordida , Carcinoma de Células Escamosas/cirugía , Diseño de Prótesis Dental , Análisis de Elementos Finitos , Reconstrucción Mandibular , Neoplasias Maxilares/cirugía , Rehabilitación Bucal/métodos , Osteosarcoma/cirugía , Satisfacción del Paciente , Periodo Posoperatorio , Reproducibilidad de los Resultados , Estudios Retrospectivos , Resultado del Tratamiento
7.
Artículo en Inglés | MEDLINE | ID: mdl-21330163

RESUMEN

OBJECTIVE: Lymphatic mapping with vital dye is often exploited during a sentinel lymph node biopsy (SLNB); however, the time restraints associated with blue dye may limit its efficacy in tongue carcinoma. Using an animal study, this exploration attempted to achieve a rational surgical modality to circumvent this hindrance. STUDY DESIGN: Forty-eight rabbits were divided into 2 equal groups: A and B; 0.2 mL methylene blue (MB) was injected into 4 parts of the tongues of the rabbits in A just after elevating the cervical flap and into the tongues of the rabbits in B just before the elevation. The times when the lymphatic vessel and lymph node turned blue and then returned pale were recorded. RESULTS: Cases in group A had significantly more time left for tracing blue-stained lymphatic vessels than those in group B. CONCLUSIONS: Elevating the cervical flap before injecting MB can alleviate the time restraint of MB as a lymphatic tracer in SLNB with tongue carcinoma.


Asunto(s)
Carcinoma/secundario , Biopsia del Ganglio Linfático Centinela/métodos , Neoplasias de la Lengua/patología , Animales , Carcinoma/patología , Colorantes , Ganglios Linfáticos/patología , Vasos Linfáticos/patología , Azul de Metileno , Disección del Cuello , Proyectos Piloto , Conejos , Distribución Aleatoria , Colgajos Quirúrgicos , Factores de Tiempo , Lengua/patología
8.
Surg Oncol ; 20(1): e1-9, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19615890

RESUMEN

BACKGROUND AND OBJECTIVES: With technical adaptations, recent studies showed SLNB could predict cervical nodes status of head and neck carcinoma with high accuracy. However, as for tongue carcinoma, such technical adaptations seem to be not enough because the tongue has peculiar characteristic which may demand a specific procedure for accurate lymphatic mapping. This investigation explored the effect of lingual septum on lymphatic mapping of tongue to provide data for achieving an accurate lymphatic mapping for managing early tongue carcinoma. METHODS: Four doses of Methylene Blue were injected into various parts of 64 rabbits' tongue, then diffusion range of Methylene Blue in tongue and sites of cervical nodes stained blue were noted. Finally, the tongues were resected for further histological examination and morphometric assessments. RESULTS: There was lingual septum in the tongue and the diffusing of Methylene Blue could be terminated by lingual septum. Blue-stained nodes were identified in 84 lateral necks of 60 rabbits. CONCLUSIONS: A site-specific way of lymphatic mapping relative to lingual septum should be developed for staging early tongue carcinoma.


Asunto(s)
Ganglios Linfáticos/anatomía & histología , Lengua/anatomía & histología , Animales , Ganglios Linfáticos/metabolismo , Azul de Metileno , Estadificación de Neoplasias , Proyectos Piloto , Conejos , Distribución Aleatoria , Lengua/metabolismo , Neoplasias de la Lengua/patología
9.
Shanghai Kou Qiang Yi Xue ; 19(2): 133-5, 2010 Apr.
Artículo en Zh | MEDLINE | ID: mdl-20485972

RESUMEN

PURPOSE: To evaluate the role of maxillary wings guiding plate in rehabilitation of combined defects of maxilla and mandible in convalescent stage. METHODS: Combined resection of maxilla and mandible without reconstruction were performed in 10 patients with oral cancers. The impressions were got in 2 patients preoperatively and 8 patients postoperatively because of preoperative limited mouth opening. The clasps were designed to provide the retentive force according to the remained teeth. The plastic palate baseboard with wings guiding plate was made. The patients wore the plate 1 week after surgery. RESULTS: All the patients get good velopharyngeal competence and occlusion without leakage from nose after using this prosthesis for 1 to 3 months. CONCLUSIONS: Palate baseboard combined with wings guiding plate can not only obstruct the nasal-oral fistula but also correct malocclusion. It's convenient for taking dental prosthesis in late stage and improving patient's quality of life. Supported by Research Fund of Science and Technology Commission of Shanghai Municipality(Grant No.08DZ2271100).


Asunto(s)
Maxilar , Calidad de Vida , Placas Óseas , Humanos , Maloclusión , Mandíbula , Procedimientos de Cirugía Plástica
10.
Shanghai Kou Qiang Yi Xue ; 19(1): 66-71, 2010 Feb.
Artículo en Zh | MEDLINE | ID: mdl-20300697

RESUMEN

PURPOSE: To investigate the role of NF-kappaB signal transduction pathway in apoptosis induced by shikonin in human tongue squamous cell carcinoma Tca-8113 cell line. METHODS: Expression of IkappaBa, phosphatase-IkappaBa, bcl-2 and Bax proteins were detected by Western blot, NF-kappaB DNA-binding activity was detected by electrophoretic mobility shift analysis (EMSA), and activities of caspase 3, caspase 8 and caspase 9 were analyzed by enzyme linked immunosorbent assay(ELISA). The data was analyzed by one-way ANOVA test and t test using SPSS12.0 software package. RESULTS: The expression of phosphatase-IkappaBa protein and the nuclear NF-kappaB DNA-binding activity was significantly decreased in shikonin treated cells by Western and EMSA. Bcl-2 protein expression was also decreased in the process. The activity of all the three proteases was elevated and pancaspase inhibitor Z-Asp-CH2-DCB could protect Tca8113 cells from shikonin-induced apoptosis(P=0.02). CONCLUSIONS: Anti-tumor effects of shikonin in Tca-8113 cells act at least partially through the inactivation of NF-kappaB pathway and subsequent activation of protease caspase family. Pharmacologic inhibition of the NF-kappaB activity by shikonin might be a powerful treatment option for OSCC.


Asunto(s)
Carcinoma de Células Escamosas , Línea Celular Tumoral , Neoplasias de la Boca , FN-kappa B , Apoptosis , Ácido Aspártico/análogos & derivados , Western Blotting , Humanos , Naftoquinonas , Transducción de Señal
11.
Zhonghua Zheng Xing Wai Ke Za Zhi ; 25(5): 332-6, 2009 Sep.
Artículo en Zh | MEDLINE | ID: mdl-20030107

RESUMEN

OBJECTIVE: To investigate the application of individualized free anterolateral thigh combined flap (ALTCF) for tongue and mouth floor defect resulted from tongue carcinoma. METHODS: From 2006 to 2008, individualized ALTCFs were used in 31 cases of tongue and mouth floor defects resulted from tongue carcinoma. The nutritional perforator vessel was musculocutaneous pattern in 22 cases and septocutaneous pattern in 9 cases. The size of the flaps and the included muscle was (4-8) cm x (5-10) cm and (2-5) cm x (3-6) cm, respectively. The length of blood vessel pedicle was (6.81 +/- 3.23) cm. RESULTS: All the 31 free flaps survived with primary healing and no complication. The appearance and function were both satisfactory. During the follow-up period of 1-3 years, 28 cases survived, 2 cases were reoperated due to the neck lymphatic metastasis on the contralateral side. 1 case died of distant metastasis. CONCLUSIONS: Individualized ALTCF is a reliable flap for the tongue and month floor defects resulted from tongue carcinoma. Both the cosmetic and functional results are satisfactory with less morbidity in donor site and less complication.


Asunto(s)
Trasplante de Piel/métodos , Colgajos Quirúrgicos , Muslo/cirugía , Neoplasias de la Lengua/cirugía , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Suelo de la Boca/patología , Procedimientos de Cirugía Plástica/métodos
12.
Shanghai Kou Qiang Yi Xue ; 17(5): 461-4, 2008 Oct.
Artículo en Zh | MEDLINE | ID: mdl-18989583

RESUMEN

PURPOSE: To investigate the clinical manifestation of branchial cleft cyst (fistula) and provide some clinical experience on its diagnosis and treatment. METHODS: From June 1993 to December 2006, two hundred and eighty-four patients with branchial cleft cyst or fistula underwent surgical treatment were retrospectively reviewed, the preoperative examinations, preoperative diagnosis and postoperative pathological diagnosis were recorded, and the data was analyzed with SAS6.12 software package. RESULTS: Among the 284 patients with branchial cleft cyst or fistula confirmed by postoperative pathological diagnosis, there were 132 patients (46.5%) with first branchial cleft cyst or fistula, one hundred and forty-five patients (51.1%) with second branchial cleft cyst or fistula, and 7 patients (2.4%) with third branchial cleft cyst or fistula. First branchial cleft cyst or fistula often occurred in patients older than 40 years, second and third branchial cleft cyst or fistula often occurred in patients younger than 40 years. The pathological diagnosis confirmed 188 primary lesions, thirty-three recurrent lesions, forty-four lesions with internal fistula, fourteen lesions with secondary infection and external fistula, and three lesions with both internal and external fistulae. One patient was found with tuberculosis simultaneously, two patients with multiple cysts, one patient with venous malformation. Six lesions were found malignant, five from first branchial cleft and one from second branchial cleft. The highest accuracy of preoperative diagnosis was 66.20% using ultrasonography. During the follow-up period, 5.98% of patients had recurrence. CONCLUSIONS: First and second branchial cleft cysts (fistula) are the most common lesions. Preoperative ultrasonography is the first choice for diagnosis of branchial cleft cyst (fistula). Complete resection including the cyst and fistula is the key to successful surgical treatment. Supported by Shanghai Leading Academic Discipline Project (Grant No.Y0203).


Asunto(s)
Branquioma , Fístula , Adulto , Región Branquial , Branquioma/diagnóstico , Branquioma/cirugía , Fístula/diagnóstico , Fístula/cirugía , Humanos , Estudios Retrospectivos
13.
Zhonghua Zheng Xing Wai Ke Za Zhi ; 23(4): 273-6, 2007 Jul.
Artículo en Zh | MEDLINE | ID: mdl-17926842

RESUMEN

OBJECTIVE: To evaluate the vascularized (deep circumflex iliac vessels) iliac crest graft with internal oblique muscle as a method for reconstruction of composite mandibular defect. METHODS: Vascularized iliac crest graft with internal oblique muscle was used to reconstruct the composite mandibular defects in 10 patients. All clinical data were analyzed retrospectively. A detailed inspection of the case-notes was undertaken to ascertain the presenting diagnosis, the surgery, the complications and the outcome. The type of mandibular defect was recorded. RESULTS: Of the 10 patients with composite mandibular defects including mandibular body, mandibular angle, mandibular ramus and the soft tissue around them, 7 patients were recorded with the defects of mandibular condyles. During the follow-up period from 3 months to 24 months, primary wound healing was observed in all patients, except one patient with minor muscular necrosis. All patients were satisfied with their facial contour and mandibular shape, without tumor recurrence. Donor site problems important enough to be recorded in the notes were minimal. CONCLUSIONS: The vascularized iliac crest graft with internal oblique muscle offers a useful solution for reconstruction of composite mandibular defect. There is sufficient height and depth of bone to maintain a facial contour and mandibular shape. It can be used as a routine surgical technique to reconstruct composite mandibular defect.


Asunto(s)
Músculos Abdominales/trasplante , Ilion/trasplante , Traumatismos Mandibulares/cirugía , Traumatismos de los Tejidos Blandos/cirugía , Adolescente , Adulto , Femenino , Humanos , Ilion/irrigación sanguínea , Masculino , Persona de Mediana Edad , Procedimientos de Cirugía Plástica/métodos , Estudios Retrospectivos , Colgajos Quirúrgicos/irrigación sanguínea , Adulto Joven
14.
Shanghai Kou Qiang Yi Xue ; 14(2): 117-9, 2005 Apr.
Artículo en Zh | MEDLINE | ID: mdl-15886830

RESUMEN

PURPOSE: To improve the contour and function of the lip and its commissure with forearm free flap suspending over fascia. METHODS: Since 2001,this method was used in 10 cases. Forearm free flap was designed according to the lip or buccal defects, then the defects were reconstructed with the flap through vascular anastomosis. The skin island for reconstruction of the intraoral lining and the skin defect was folded over the palmaris longus tendon or fascia lata. RESULTS: All the patients were followed-up for 2 years, the survival rate of the free flap was 100%, 2 patients had oral incompetence, the others had good oral function and sufficient oral competence. The flaps were helpful to expression of motion. CONCLUSION: Reconstruction of total lower lip or corner of mouth defects with forearm free flap suspending over fascia was helpful for rehabilitation of contour and oral function.


Asunto(s)
Fasciotomía , Boca/cirugía , Procedimientos de Cirugía Plástica/métodos , Antebrazo/cirugía , Colgajos Tisulares Libres/cirugía , Humanos , Labio/cirugía , Colgajos Quirúrgicos/cirugía
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