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1.
J Org Chem ; 85(12): 7793-7802, 2020 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-32469521

RESUMEN

Based on a novel umpolung strategy, an efficient and highly enantioselective cascade aldol/cyclization/tautomerization of the 2-(2-oxoindolin-3-yl)malononitrile to active carbonyl compounds with excellent diastereo- and enantioselectivity has been developed. Also, various enantio-enriched multifunctional dispiro[2-amino-4,5-dihydrofuran-3-carbonitrile]bisoxindoles with adjacent spiro-stereocenters were conveniently obtained by this novel methodology. Also, the dispiro[2-amino-4,5-dihydrofuran-3-carbonitrile]bisoxindoles were easily transformed into structurally complex molecules without any effect on the diastereo- and enantioselectivity.

2.
Genet Med ; 19(5): 553-558, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-27657680

RESUMEN

PURPOSE: To explore the genetic etiology of deafness in a dominant family with late-onset, progressive, nonsyndromic hearing loss. METHODS: Genome-wide linkage analysis was performed for 21 family members. Candidate pathogenic variants were identified by whole-exome sequencing of selected family members and confirmed by Sanger sequencing of all family members. Cochlear expression of Dmxl2 was investigated by reverse-transcription polymerase chain reaction (RT-PCR) and immunostaining of the organ of Corti from mice. RESULTS: The causative gene was mapped to a 9.68-Mb candidate region on chromosome 15q21.2 (maximum logarithm of the odds score = 4.03) that contained no previously described deafness genes. Whole-exome sequencing identified heterozygous c.7250G>A (p.Arg2417His) in DMXL2 as the only candidate pathogenic variant segregating the hearing loss. In mouse cochlea, expression of DMXL2 was restricted to the hair cells and the spiral ganglion neurons. CONCLUSION: Our data indicated that the p.Arg2417His variant in DMXL2 is associated with dominant, nonsyndromic hearing loss and suggested an important role of DMXL2 in inner ear function.Genet Med advance online publication 22 September 2016.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Sordera/genética , Mutación Missense , Proteínas del Tejido Nervioso/genética , Órgano Espiral/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Edad de Inicio , Animales , China/etnología , Sordera/metabolismo , Femenino , Estudios de Asociación Genética , Ligamiento Genético , Predisposición Genética a la Enfermedad , Humanos , Masculino , Ratones , Proteínas del Tejido Nervioso/metabolismo , Linaje , Mapeo Físico de Cromosoma , Secuenciación del Exoma
3.
BMC Cancer ; 17(1): 652, 2017 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-28923053

RESUMEN

BACKGROUND: The increasing incidence and poor outcome associated with malignant pleural effusion (MPE) requires finding an effective treatment for this disease. Inhibitory B7-H4 is expressed in many different human cancers but its role in malignant pleural tissue has yet to be established. METHODS: Here, patients with metastatic pleural adenocarcinoma (MPA) or with early-stage lung adenocarcinoma were clinically and statistically analyzed. Immunohistochemistry and confocal microscopy were used to determinate the expression of B7-H4 in the cancer cells. By using MPE model, we sought to a potential immunotherapy for MPE with anti-B7-H4 mAb. RESULTS: When compared to early-stage lung adenocarcinoma, MPA possessed higher level of nuclei membranous B7-H4 and lower cytoplasmic B7-H4 expression. Also, nuclei membranous B7-H4 expression was found to be positively correlated to Ki-67 expression, and indicated a possible poor prognosis of MPA. In mouse MPE model, intra-pleurally injection of anti-B7-H4 mAb effectively suppressed MPE formation. CONCLUSIONS: Taken together, our data was in support of the significance of B7-H4 expression in MPA, which also suggest it warrants further exploration for potential immunotherapy of MPE.


Asunto(s)
Adenocarcinoma/metabolismo , Antineoplásicos/farmacología , Neoplasias Pulmonares/metabolismo , Neoplasias Pleurales/metabolismo , Inhibidor 1 de la Activación de Células T con Dominio V-Set/metabolismo , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/secundario , Animales , Carcinoma Pulmonar de Lewis/tratamiento farmacológico , Carcinoma Pulmonar de Lewis/metabolismo , Línea Celular Tumoral , Citoplasma/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Masculino , Ratones Endogámicos C57BL , Persona de Mediana Edad , Trasplante de Neoplasias , Membrana Nuclear/metabolismo , Derrame Pleural Maligno , Neoplasias Pleurales/tratamiento farmacológico , Neoplasias Pleurales/secundario , Inhibidor 1 de la Activación de Células T con Dominio V-Set/antagonistas & inhibidores
4.
Zhonghua Nan Ke Xue ; 23(5): 392-398, 2017 May.
Artículo en Zh | MEDLINE | ID: mdl-29717827

RESUMEN

OBJECTIVE: To explore the effects of immediate and delayed intracavernous injection of bone marrow mesenchymal stem cells (BM-MSCs) on neurogenic erectile dysfunction (NED) induced by bilateral cavernous nerve injury in Sprague-Dawley (SD) rats. METHODS: BM-MSCs isolated from male SD rats were cultured and identified. Twenty-eight 8-week-old male SD rats were randomly divided into four groups, sham operation, NED model control, BM-MSCs immediate, and BM-MSCs delayed, and NED models were established in the latter three groups by crushing the bilateral cavernous nerves. The rats in the sham operation and model control groups were injected intracavernously with placebo while those in the latter two with BM-MSCs immediately or 2 weeks after modeling. At 12 weeks after operation, the penile function of the rats was assessed according to the penile intracavernous pressure (ICP), mean arterial pressure (MAP), and ICP/MAP ratio obtained from different groups of rats. Then, all the animals were sacrificed and the penile cavernosal tissue collected for histological analysis. RESULTS: At 12 weeks after modeling, both ICP and ICP/MAP were significantly increased in the BM-MSCs immediate and delayed groups as compared with those in the model control (P <0.05), and so were the ratio of smooth muscle to collagen (P <0.05) and the smooth muscle content in the corpus cavernosum (P <0.05), and the number of neurofilament (NF)-positive nerve fibers (P <0.05) and the expression of neuronal nitric oxide synthase (nNOS) in the dorsal nerves of the midshaft penis (P <0.05). CONCLUSIONS: Intracavernous injection of BM-MSCs can improve erectile function in rats with bilateral cavernous nerve injury by elevating the smooth muscle-collagen ratio and smooth muscle content in the corpus cavernosum and thus preventing its fibrosis as well as by increasing the number of NF-positive nerve fibers and expression of nNOS in the penile dorsal nerves.


Asunto(s)
Disfunción Eréctil/terapia , Trasplante de Células Madre Mesenquimatosas/métodos , Pene/inervación , Animales , Modelos Animales de Enfermedad , Disfunción Eréctil/enzimología , Disfunción Eréctil/etiología , Masculino , Músculo Liso , Óxido Nítrico Sintasa de Tipo I/metabolismo , Erección Peniana/fisiología , Pene/enzimología , Nervio Pudendo , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley
5.
Eur Arch Otorhinolaryngol ; 273(5): 1115-21, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-25997899

RESUMEN

The aim of the study was to describe the refinements to the classic enlarged translabyrinthine approach (ETLA) by modifying the bony dissection range of temporal bone and to analyze the main outcomes achieved in a series of vestibular schwannoma (VS) cases submitted to microsurgery by ETLA. This was a retrospective study of 382 patients who underwent VS surgical removal via ETLA between January 2001 and December 2012. Among those cases, 332 were via classic ETLA, while 28 cases were via ETLA with blind sac technique and middle ear eradication and 22 via transotic approach. Total tumor removal was achieved in 368 cases, whereas near total removal in 11 patients and subtotal in 3 patients. In cases of large VS (>3 cm) via classic ETLA, good short-term and long-term facial nerve function (HB I-II) was gained in 27.8 % (32/115) and 42.6 % (49/115) cases, respectively, meanwhile in VS operated via blind sac technique, good short-term (p = 0.048) and long-term (p = 0.044) facial nerve function was reached in 44.0 % (22/50) and 60.0 % (30/50) cases, respectively. Postoperative facial nerve function was proved to be better in modified ETLA group. CSF leakage occurred in 16 (4.2 %) patients via classic ETLA. In 115 cases of large VS (>3 cm), postoperative CSF leakage occurred in 10 (8.7 %) patients. Whereas in 50 cases via blind sac technique, none developed CSF leakage (p = 0.03). The incidence of CSF leakage was lower in modified ETLA group. Our refinements to classic ETLA by changing the temporal bone resection range provide a wide surgical field, well prevention of CSF leakage and preservation of facial nerve function in large VS.


Asunto(s)
Pérdida de Líquido Cefalorraquídeo/prevención & control , Toma de Decisiones Clínicas , Disección/efectos adversos , Microcirugia/efectos adversos , Neuroma Acústico/cirugía , Hueso Temporal/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Pérdida de Líquido Cefalorraquídeo/diagnóstico , Pérdida de Líquido Cefalorraquídeo/epidemiología , Disección/métodos , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Neuroma Acústico/patología , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Estudios Retrospectivos , Hueso Temporal/patología , Adulto Joven
6.
Br J Biomed Sci ; 73(1): 32-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27182675

RESUMEN

PURPOSE: This study was designed to determine whether proliferation antigen Ki-67 and/or a computed tomography (CT) value could be used to evaluate the clinical-pathological features of peripheral lung adenocarcinoma. MATERIALS AND METHODS: A total of 116 eligible lung cancer patients were enrolled. Nodule size, lymph node metastasis, differentiation, Ki-67 expression and CT findings were assessed. The relationship between clinic parameters and the CT feature was analysed statistically. RESULTS: The percentage of lesions that had ground-glass opacity or localised air bronchogram was significantly greater in low CT value group (<30, p < 0.05). No significant association was observed between CT value and size in the subgroup with CT value > 0 (p = 0.66). As a proliferative marker of lung cancer, Ki-67 was present in a total of 115 (99.9%) of the 116 evaluable primary lung cancers. There was a statistically significant correlation between the Ki-67 index and CT value (p < 0.05). Compared to CT value, Ki-67 index possessed higher sensitivity to predict the differentiation and lymph node metastasis of peripheral lung adenocarcinoma, adding of CT value would enhance its specificity. CONCLUSION: Combination of Ki-67 expression and CT value determination was useful for the classification of differentiation and metastatic or proliferative potential of peripheral lung adenocarcinoma.


Asunto(s)
Adenocarcinoma/diagnóstico , Biomarcadores de Tumor/análisis , Proliferación Celular , Inmunohistoquímica , Antígeno Ki-67/análisis , Neoplasias Pulmonares/diagnóstico , Tomografía Computarizada por Rayos X , Adenocarcinoma/química , Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/secundario , Adenocarcinoma/cirugía , Adenocarcinoma del Pulmón , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Diferenciación Celular , Femenino , Humanos , Neoplasias Pulmonares/química , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/cirugía , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Resultado del Tratamiento , Carga Tumoral
7.
Zhonghua Nan Ke Xue ; 22(9): 771-776, 2016 Sep.
Artículo en Zh | MEDLINE | ID: mdl-29071871

RESUMEN

OBJECTIVE: To explore the expression of I-5α-reductase (SRD5A1)and its prognostic role in prostate cancer . METHODS: Data about SRD5A1 were retrieved from the ONCOMINE database and the role of SRD5A1 in prostate cancer was analyzed. RESULTS: Totally, 992 studies of different types relevant to the expression of SRD5A1 were identified in the ONCOMINE database. The SRD5A1 expression was statistically significant in 239 of the studies, overexpressed in 157 (11 in prostate cancer) and underexpressed in the other 82 (3 in prostate cancer). Eighteen of the studies, with 1 068 samples, addressed the expression of SRD5A1 in prostate cancer and normal tissues, which was significantly higher in the former than in the latter tissue (P<0.05). In 3 of the studies, the SRD5A1 expression was high in primary prostate cancer and increased with its metastasis (P<0.0 5). Two of the studies with prognostic data showed a higher rate of postoperative biochemical recurrence and a higher total mortality rate in the patients with a high than in those with a low expression of SRD5A1 (P<0.05). CONCLUSIONS: SRD5A1 is highly expressed in prostate cancer, especially in metastatic and castration-resistant prostate cancer and its expression is associated with the prognosis of prostate cancer, which may be an important target of medication for prostate cancer.


Asunto(s)
3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa/metabolismo , Minería de Datos , Neoplasias de la Próstata/enzimología , Humanos , Masculino , Recurrencia Local de Neoplasia , Pronóstico , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata Resistentes a la Castración/enzimología
8.
Zhonghua Nan Ke Xue ; 22(12): 1083-1087, 2016 Dec.
Artículo en Zh | MEDLINE | ID: mdl-29282912

RESUMEN

OBJECTIVE: To explore the expression of long noncoding RNA (lncRNA) LINC01358 in prostate cancer (PCa) and its effect on the proliferation and migration of PCa cells. METHODS: The lncRNA array was used to screen differentially expressed lncRNAs in PCa and the corresponding carcinoma-adjacent normal tissues from 3 patients. The expressions of LINC01358 in the primary PCa, metastatic PCa, and carcinoma-adjacent tissues were compared using the PCa dataset of the Memorial Sloan Kettering Cancer Center (MSKCC). The data obtained were validated by determining the expression of LINC01358 in the PCa and carcinoma-adjacent tissues of another 10 patients by quantitative real time PCR (qRT-PCR). The effects of lncRNA LINC01358 on the proliferation of DU145 cells and migration of PCa cells were detected by MTT and Transwell assay, respectively. RESULTS: Totally, 79 differentially expressed lncRNAs in the lncRNA array, 36 highly and the other 43 lowly expressed in the PCa tissue. LINC01358 was up-regulated in the cancerous tissue. According to the MSKCC data, the LINC01358 expression was markedly higher in metastatic PCa (5.81±0.19, n = 19) and primary PCa (5.47±0.04, n = 131) than in the PCa-adjacent tissue (5.15±0.07, n = 29) and significantly correlated with postoperative biochemical relapse of the malignancy (P<0.05). qRT-PCR indicated a remarkably higher expression of LINC01358 in the PCa than in the carcinoma-adjacent tissue (6.02±1.12 vs 3.21±0.21, P<0.05). Transfection of the DU145 cells with siRNA significantly decreased the level of LINC01358 and inhibited the proliferation and migration of the PCa cells. CONCLUSIONS: LINC01358 is highly expressed in the PCa tissue and knockdown of LINC01358 may inhibit the proliferation and migration of PCa cells. LncRNA LINC01358 may be involved in the development and progression of PCa and become an index for the early diagnosis as well as a new target for the gene therapy of the malignancy.


Asunto(s)
Movimiento Celular , Proliferación Celular , Neoplasias de la Próstata/metabolismo , ARN Largo no Codificante/metabolismo , Línea Celular Tumoral , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Neoplasias de la Próstata/patología , ARN Interferente Pequeño , Transfección , Regulación hacia Arriba
9.
J Org Chem ; 80(22): 11521-8, 2015 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-26474033

RESUMEN

A formal thio [3+2] cyclization catalyzed by Takemoto's organocatalyst has been reported for the construction of optically active spiroannulated dihydrothiophenes in high yields with excellent regio-, chemo-, diastereo-, and enantioselectivities.

10.
Zhonghua Nan Ke Xue ; 21(10): 904-7, 2015 Oct.
Artículo en Zh | MEDLINE | ID: mdl-26665679

RESUMEN

OBJECTIVE: To compare the outcomes and complications of 3D versus 2D laparoscopic radical prostatectomy ( LRP) in the treatment of prostate cancer. METHODS: We retrospectively reviewed 18 cases of prostate cancer treated by 3D LRP and another 32 by 2D LRP. We compared the general data, intraoperative blood loss, postoperative drainage time and hospital stay, Gleason scores, and incidence of complications between the two groups of patients. RESULTS: All the operations were successful and none was transferred to open surgery. The two groups of patients were similar in terms of age, body mass index, Gleason scores, and clinical stages. However, compared with the 2D LRP group, the 3D LRP group showed significantly shorter operation time ([180.2 ± 69.1] vs [118.3 ± 55.1] min, P < 0.01), less blood loss ([236.5 ± 60.6] vs [89.1 ± 35.2] ml, P < 0.01), less postoperative drainage time ([7.1 ± 1.1] vs [5.3 ± 2.1] d, P < 0.01), shorter postoperative hospital stay ([20.2 ± 5.5] vs [14.4 ± 7.2] d, P < 0.01), and lower incidence of perioperative complications (3.1% vs 0, P < 0.01). The incisal margin was pathologically negative in both groups and urinary incontinence was found in neither at 6 months after surgery (P > 0.05). CONCLUSION: 3D LRP, with its advantages of shorter operative time, faster recovery, and better outcomes than 2D LRP in the treatment of prostate cancer, deserves general application in lower-level hospitals.


Asunto(s)
Pérdida de Sangre Quirúrgica , Laparoscopía/métodos , Prostatectomía/métodos , Neoplasias de la Próstata/cirugía , Índice de Masa Corporal , Drenaje , Humanos , Laparoscopía/efectos adversos , Tiempo de Internación , Masculino , Clasificación del Tumor , Tempo Operativo , Prostatectomía/efectos adversos , Neoplasias de la Próstata/patología , Recuperación de la Función , Estudios Retrospectivos , Incontinencia Urinaria/etiología
11.
PLoS One ; 19(6): e0303694, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38870188

RESUMEN

OBJECTIVE: This study investigates the association between physical exercise and emotion regulation abilities among college students, introducing self-efficacy as a mediating variable to analyze the pathway mechanism through which physical exercise affects emotion regulation abilities. METHODS: A cross-sectional study design was employed, utilizing a stratified random sampling method to survey three colleges in Jiangsu Province, China. Physical Activity Rating Scale, Physical Activity Self-efficacy Scale, and Emotional Intelligence Scale were used to measure the college student population. Regression analysis and mediation tests assessed whether self-efficacy mediates the relationship between physical exercise and college students' emotion regulation abilities. A total of 5,430 valid questionnaires were collected. RESULTS: The distribution of college students' physical activities was 77.0% for low, 13.1% for medium, and 9.3% for high levels. Physical activities were significantly and positively correlated with self-efficacy and emotional management abilities (r = 0.298,0.105;P<0.01), and self-efficacy was significantly and positively correlated with emotional management abilities (r = 0.322, P<0.01). Situational motivation and subjective support under self-efficacy were 0.08 and 0.255, respectively, and the adjusted R2 was 0.107. Self-efficacy played a fully mediating role between physical activities and emotional management abilities, with a total effect value of 0.032. The values of the direct and indirect effects were 0.003 and 0.029, accounting for 8.95% and 90.74% of the total effect, respectively. CONCLUSION: The physical exercise behavior of college students is primarily characterized by low intensity. Physical exercise among college students can positively predict their ability to regulate emotions. Self-efficacy fully mediates the relationship between physical exercise and emotion regulation ability among college students. College students can indirectly influence their ability to regulate emotions through physical exercise and self-efficacy.


Asunto(s)
Afecto , Regulación Emocional , Ejercicio Físico , Autoeficacia , Estudiantes , Humanos , Ejercicio Físico/psicología , Ejercicio Físico/fisiología , Masculino , Femenino , Adulto Joven , Regulación Emocional/fisiología , Estudiantes/psicología , Estudios Transversales , Afecto/fisiología , Adulto , Encuestas y Cuestionarios , Adolescente , Universidades , China , Emociones/fisiología
12.
Front Public Health ; 12: 1402801, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38765486

RESUMEN

Background: Negative emotions in college students are a significant factor affecting mental health, with suicide behaviors caused by negative emotions showing an annual increasing trend. Existing studies suggest that physical exercise is essential to alleviate negative feelings, yet the intrinsic mechanisms by which it affects negative emotions have not been fully revealed. Objective: Negative emotions in college students represent a significant issue affecting mental health. This study investigates the relationship between physical exercise and negative emotions among college students, incorporating sleep quality and self-rated health (SRH) as mediators to analyze the pathway mechanism of how physical exercise affects students' negative emotions. Methods: A cross-sectional study design was utilized, employing online questionnaires for investigation. The scales included the Physical Activity Rating Scale-3 (PARS-3), the Depression Anxiety Stress Scales-21 (DASS-21), the Pittsburgh Sleep Quality Index (PSQI), and the 12-Item Short Form Health Survey (SF-12), resulting in the collection of 30,475 valid questionnaires, with a validity rate of 91%. Chain mediation tests and Bootstrap methods were applied for effect analysis. Results: The proportions of university students engaged in low, medium, and high levels of physical exercise were 77.6, 13.1, and 9.3%, respectively. The proportions of students experiencing "very severe" levels of stress, anxiety, and depression were 4.5, 10.9, and 3.6%, respectively. Physical exercise was significantly positively correlated with self-rated health (r = 0.194, p < 0.01), significantly negatively correlated with sleep quality (r = -0.035, p < 0.01), and significantly negatively correlated with stress, anxiety, and depression (r = -0.03, p < 0.01; r = -0.058, p < 0.01; r = -0.055, p < 0.01). Sleep quality was significantly negatively correlated with self-rated health (r = -0.242, p < 0.01). Mediation effect testing indicated that sleep quality and self-rated health partially mediated the relationship between physical exercise and negative emotions, with total effect, total direct effect, and total indirect effect values of -1.702, -0.426, and - 1.277, respectively. Conclusion: College students primarily engage in low-intensity physical activity. Sleep quality and self-rated health mediate the impact of physical exercise on students' negative emotions. A certain level of physical activity can directly affect students' emotional states and indirectly influence their negative emotions via sleep and self-rated health. Regular engagement in physical activities primarily positively impacts emotional states by enhancing mood stability and overall emotional resilience.


Asunto(s)
Emociones , Ejercicio Físico , Calidad del Sueño , Estudiantes , Humanos , Masculino , Estudiantes/psicología , Femenino , Ejercicio Físico/psicología , Estudios Transversales , Universidades , Encuestas y Cuestionarios , Adulto Joven , Emociones/fisiología , Adulto , Adolescente , Depresión/psicología , Estado de Salud , Salud Mental
13.
Org Biomol Chem ; 10(42): 8471-7, 2012 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-23001215

RESUMEN

A highly regio-, chemo-, diastereo- and enantioselective organocatalytic [4 + 1] annulation of 2-halo-1,3-dicarbonyl compounds with Morita-Baylis-Hillman adducts catalyzed by commercially available, low cost quinidine for the preparation of synthetically unique and medicinally multi-functionalized isoxazoline N-oxides with three stereogenic centers including adjacent quaternary and tertiary stereocenters has been developed. Notably, the unexpected product ethyl 2-((tert-butyldimethylsilyl)oxy)-2-(5,5-diacetyl-3-((methylsulfonyl)oxy)-4-phenylisoxazolidin-3-yl)acetate (8) bearing a quaternary stereocenter and two tertiary stereocenters was obtained from the undocumented 5,5-diacetyl-3-(2-ethoxy-1-hydroxy-2-oxoethyl)-4-phenyl-4,5-dihydroisoxazole 2-oxide (4ba).


Asunto(s)
Isoxazoles/química , Óxidos/química , Quinidina/química , Catálisis , Isoxazoles/síntesis química , Modelos Moleculares , Óxidos/síntesis química , Estereoisomerismo
14.
Org Biomol Chem ; 10(32): 6554-61, 2012 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-22760526

RESUMEN

A series of functionalized 2,3-dihydro-1,4-benzoxazines were obtained in moderate to excellent yields via domino [5 + 1] annulations of 2-halo-1,3-dicarbonyl compounds 2 with imines 1 under mild conditions and the application of this method in the synthesis of bioactive analogues, such as functionalized tetracyclic-1,4-benzoxazines which contain two new heterocyclic rings and one quaternary carbon center has also been developed.


Asunto(s)
Benzoxazinas/síntesis química , Halógenos/química , Iminas/química , Benzoxazinas/química , Química Farmacéutica , Cristalografía por Rayos X , Compuestos Heterocíclicos/síntesis química , Compuestos Heterocíclicos/química , Estructura Molecular
15.
Org Biomol Chem ; 10(2): 244-7, 2012 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-22021002

RESUMEN

α,α-Dicyanoolefins react with hydroxylamine to afford 2,3-dihydroisoxazoles (2,3-dihydroisoxazoles can be easily isolated by filtration) in excellent yields under mild and environmentally benign conditions. A one-pot reaction in tandem with an unexpected ring-opening of 2,3-dihydroisoxazoles has been developed as well.


Asunto(s)
Acrilamida/síntesis química , Isoxazoles/síntesis química , Agua/química , Acrilamida/química , Isoxazoles/química , Estructura Molecular
16.
Nanotechnology ; 23(45): 455204, 2012 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-23090358

RESUMEN

The field emission (FE) properties of TiO(2) nanotube arrays (TNAs) synthesized by anodization are dramatically improved after hydrogenation at various temperatures in a range of 400-550 °C. Compared with pristine TNAs, the turn-on fields of hydrogenated TNAs (H:TNAs) are significantly decreased from 18.23 to 1.75 V µm(-1), and closely related to hydrogenation temperature. Importantly, the optimized sample of H:TNAs prepared at 550 °C shows excellent FE performances involving both a low turn-on field of 1.75 V µm(-1), a high current density of 4.0 mA cm(-2) at 4.50V µm(-1), and a remarkable FE stability over 480 min. The substantially enhanced FE properties can be attributed to the combination of a typical tubular morphology, a reduced work function and the improved conductivity of H:TNAs.

17.
Beijing Da Xue Xue Bao Yi Xue Ban ; 44(1): 22-8, 2012 Feb 18.
Artículo en Zh | MEDLINE | ID: mdl-22353894

RESUMEN

OBJECTIVE: This study was to longitudinally evaluate the change of prevalence of five periodontal putative pathogens in the subgingival plaque of artificial class III furcation defects at the three time-points, including before the establishment of furcation defects, before and 6 months after periodontal surgery. METHODS: Eighteen chronic infected class III FI defects were created at the mandibular first molars, second molars and second premolars of three adult male Macaca fascicularis. The samples of subgingival plaque were obtained from the subgingival area of furcation defects in buccal and lingual sites before the establishment of furcation defects, before and 6 months after periodontal surgery. 36 samples were obtained at one time-points. Five periodontal putative pathogens, including Porphyromonas gingivalis (Pg), Tannerella forsythensis (Tf), Treponema dinticola (Td), Actinobacillus actinomycetemcomitans (Aa) and Fusobacterium nucleatum (Fn), were detected with 16SrRNA based PCR. RESULTS: 1. The prevalence of Pg, Tf, Td and Fn was gradually increased, from 58.3% to 69.4% to 88.9%, 47,2% to 69.4% to 83.3%, 13.9% to 36.1% to 61.1% (P<0.01), and 69.4% to 91.7% to 91.7% (P<0.05), respectively during the experimental period. The prevalence of Fn was higher than Pg, Tf and Td. The prevalence of Aa was the lowest and no obvious difference among the three samplings(from 25.9% to 13.9% to 33.3%)was detected. 2. The prevalence of more than 3 species simultaneously detected was increased from 38.9% to 61.1% to 83.3% (P <0.01). The red complex (Pg + Tf + Td) was detected from 8.3% to 27.8% to 44.4% (P<0.01) at the different time point. 3. The combined detection frequency of red complex in the inflammatory sites (87.5%), which were histologically defined as inflammatory cells infiltrated in furcation area 6 months post-surgery, and the same sites pre-surgery (62.5%) was more than that in pre-creation of furcation defects (P<0.01). But there were no significant differences compared to that in non inflammatory area (60.0%, 40.0%), respectively. CONCLUSION: The prevalence of periodontal pathogenic bacteria correlated with the severity of local inflammation. The increase of coexistent rate of red complex at the second and third sampling times suggests that the red complex play important role in the pathogenesis of periodontitis. Fn may be a resident bacteria in the subgingival plaque, play a bridge role on the biofilm formation and maturation. Aa may not be a major causative bacteria in the clinical periodontitis.


Asunto(s)
Placa Dental/microbiología , Defectos de Furcación/microbiología , Periodontitis/microbiología , Aggregatibacter actinomycetemcomitans/aislamiento & purificación , Animales , Defectos de Furcación/etiología , Fusobacterium nucleatum/aislamiento & purificación , Estudios Longitudinales , Macaca fascicularis , Masculino , Periodontitis/complicaciones , Periodontitis/cirugía , Porphyromonas gingivalis/aislamiento & purificación , Treponema denticola/aislamiento & purificación
18.
Nat Prod Res ; 36(17): 4371-4378, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34965786

RESUMEN

Four flavonoid glycosides containing coumaroyl or feruloyl groups were isolated from the male flowers of Ginkgo biloba L., and compounds 3 and 4 were identified as novel compounds. The inhibitory activities against α-glucosidase were investigated by docking studies, in vitro assays and kinetic studies. The docking results showed that all compounds mainly formed hydrogen-bond and π-π-stacking interactions with α-glucosidase. Compound 4 had the lowest binding energy and maximum number of hydrogen bonds. Subsequently, the in vitro assays showed that compound 4 exhibited the strongest inhibitory potency. Finally, the kinetic studies indicated the inhibitory mode of compounds 1-4 against α-glucosidase were mixed types of competitive and non-competitive. Together, these findings suggested that the isolated flavonoid glycosides in this study, especially compound 4, have potential as α-glucosidase inhibitors.


Asunto(s)
Flavonoides , Ginkgo biloba , Flavonoides/química , Flores/química , Ginkgo biloba/química , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/farmacología , Glicósidos/química , Cinética , Simulación del Acoplamiento Molecular , alfa-Glucosidasas/metabolismo
19.
Int J Med Robot ; 18(1): e2346, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34695880

RESUMEN

BACKGROUND: The purpose of this study is to develop a methodology to better control a human-robot collaboration for robotic dental implant placement. We have designed a human-robot collaborative implant system (HRCDIS) which is based on a zero-force hand-guiding concept and a operational task management workflow that can achieve highly accurate and stable osteotomy drilling based on a surgeon's decision and robotic arm movements during implant surgery. METHOD: The HRCDIS brings forth the robot arm positions, exact drilling location, direction and performs automatic drilling. The HRCDIS can also avoid complex programing in the robot. The purpose of the study is to evaluate the accuracy of drilling resulting from our developed operational task management method (OTMM). The OTMM can enable the robot to switch, pause, and resume drilling tasks. The force required for hand-guiding in a zero-force control mode of the robot was detected by a 6D force sensor. We compared our force data to those provided by the manufacturer's manual. The study was conducted on a phantom head with a 3D-printed jaw bone to verify the validity of our HRCDIS. We appraised the discrepancies between free-hand drillings and the HRCDIS controlled drillings at apical centre and head centre of the implant and implant angulation to the baseline data from a virtual surgical planning model. RESULTS: The average required force used by hand-guiding to operate the robot with HRCDIS was near 7 Newton which is much less than the manufacturer's specification (30 Newton). The results from our study showed that the average error at implant head was 1.04 ± 0.37 mm, 1.56 ± 0.52 mm at the implant apex, and deviation of implant angle was 3.74 ± 0.67°. CONCLUSIONS: The results from this study validate the merit of the human-robot collaboration control by the HRCDIS. Based on the improved navigation system using HRCDIS, a robotic implant placement can provide seamless drilling with ease, efficiency and accuracy.


Asunto(s)
Implantes Dentales , Procedimientos Quirúrgicos Robotizados , Robótica , Cirugía Asistida por Computador , Humanos , Fantasmas de Imagen
20.
Neural Regen Res ; 17(5): 1125-1130, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34558541

RESUMEN

Both interposition nerve grafts and masseter nerve transfers have been successfully used for facial reanimation after irreversible injuries to the cranial portion of the facial nerve. However, no comparative study of these two procedures has yet been reported. In this two-site, two-arm, retrospective case review study, 32 patients were included. Of these, 17 patients (eight men and nine women, mean age 42.1 years) underwent interposition nerve graft after tumor extirpation or trauma between 2003 and 2006 in the Ear Institute, School of Medicine, Shanghai Jiao Tong University, China, and 15 patients (six men and nine women, mean age 40.6 years) underwent masseter-to-facial nerve transfer after tumor extirpation or trauma between November 2010 and February 2016 in Shanghai Ninth People's Hospital, China. More patients achieved House-Brackmann III recovery after masseter nerve repair than interposition nerve graft repair (15/15 vs. 12/17). The mean oral commissure excursion ratio was also higher in patients who underwent masseter nerve transfer than in patients subjected to an interposition nerve graft. These findings suggest that masseter nerve transfer results in strong oral commissure excursion, avoiding obvious synkinesis, while an interposition nerve graft provides better resting symmetry. This study was approved by the Institutional Ethics Committee, Shanghai Ninth People's Hospital, China (approval No. SH9H-2019-T332-1) on December 12, 2019.

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