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1.
Phys Chem Chem Phys ; 25(37): 25818-25827, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37724461

RESUMEN

The nitrogen-vacancy center doped with hydrogen (NVH) is one of the most common defects in diamonds, and the doping of hydrogen is known to enable mobility among three equivalent C-radicals in the defect, which noticeably affects the spin coupling among the radicals. Here, we for the first time uncover the dynamic nature of magnetic coupling induced by H-migration in the NVH center of nanodiamonds, using spin-polarized density functional theory calculations and enhanced sampling metadynamics simulations. The mobility of doping H enables the interior NVH region to become a variable magnetic space (antiferromagnetic/AFM versus ferromagnetic/FM). That is, the dynamic H has three frequently reachable binding C sites where H enables the center to exhibit variable AFM coupling (high up to J = -1282 cm-1) and that in other H-reachable regions including N sites, it enables the center to exhibit FM coupling (high up to J = 598 cm-1). The magnetic switching (AFM ↔ FM) and strength fluctuation strongly depend on the H-position which can adjust the ratio of the C radical orbitals in their mixing orbitals for a special three-electron three-center covalent C⋯H⋯C H-bonding and radical orbital distributions. Clearly, this work provides insights into the dynamic switching of magnetic coupling in such multi-radical centers of defect nanodiamonds.

2.
Med Sci Monit ; 26: e924724, 2020 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-33184252

RESUMEN

BACKGROUND Bone fracture, a common injury to bones leads to various biophysiological changes and pathological responses in the body. The current study investigated curcumin for treatment of bone fracture in a rat model of bone trauma, and evaluated the related mechanism. MATERIAL AND METHODS The rats were separated randomly into 3 groups; sham, model, and curcumin treatment groups. The fracture rat model was established by transverse osteotomy in the right femur bone at the mid-shaft. The osteoblast count was determined using hematoxylin and eosin staining. Vascular endothelial growth factor (VEGF) and proliferating cell nuclear antigen (PCNA) expression were measured by western blotting. RESULTS The rpS6-phosphorylation was suppressed and light chain 3 (LC3II) expression elevated in the curcumin treated group of the fracture rat model. In the curcumin-treated group, mineralization of fracture calluses was markedly higher on day 14 of fracture. The formation of osteoblasts was observed at a greater rate in the curcumin treated group compared to the model rat group. Treatment of rats with curcumin significantly (P<0.05) promoted expression of PCNA and VEGF. The decrease in CD11b+/Gr-1+ cell expansion in rats with bone trauma was alleviated significantly by curcumin treatment. A marked increase in arginase-1 expression in rats with bone trauma was caused by curcumin treatment. CONCLUSIONS In summary, curcumin activates autophagy and inhibits mTOR activation in bone tissues of rats with trauma. The curcumin promoted myeloid-derived suppressor cell (MDSC) proliferation and increased expansion of MDSCs in a rat model of trauma. Therefore, curcumin may have beneficial effect in patients with bone trauma and should be evaluated further for development of treatment.


Asunto(s)
Huesos/patología , Curcumina/farmacología , Células Supresoras de Origen Mieloide/patología , Sustancias Protectoras/farmacología , Heridas y Lesiones/patología , Animales , Arginasa/metabolismo , Huesos/efectos de los fármacos , Callo Óseo/efectos de los fármacos , Callo Óseo/patología , Antígeno CD11b/metabolismo , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Fracturas del Fémur/patología , Masculino , Proteínas Asociadas a Microtúbulos/metabolismo , Células Supresoras de Origen Mieloide/efectos de los fármacos , Células Supresoras de Origen Mieloide/metabolismo , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteoblastos/patología , Fosforilación/efectos de los fármacos , Antígeno Nuclear de Célula en Proliferación/metabolismo , Ratas Sprague-Dawley , Proteína S6 Ribosómica/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Heridas y Lesiones/metabolismo
3.
Cancer Med ; 9(11): 3703-3713, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32237070

RESUMEN

OBJECTIVE: Despite the proven benefits of adjuvant endocrine therapy, adherence to oral endocrine therapy in breast cancer treatment is a substantial problem. The aim of this study was to assess adherence to adjuvant endocrine therapy by women in China for the first 5 years, and to identify its influencing factors. METHODS: Stratified sampling method was adopted to select 1875 cases of breast cancer patients for cross-sectional telephone follow-up. Compliance to medications was assessed using the Morisky Medication Adherence Scale. Status of endocrine therapy was assessed using nine additional questions. Binomial regression was used when assessing the factors associated with persistence, multinomial regression models were used to assess factors associated with compliance. RESULTS: Of 888 patients who started adjuvant endocrine therapy, 769(86.6%) persisted and 119 (13.4%) discontinued. 760 patients who completed Morisky Medication Adherence Scale, the compliance was 7.4% low, 42% medium, and 50.6% high. The type of medication, duration of medication and side effects had an impact both on persistence and compliance. Age, history of radiotherapy and caregivers only had an impact on persistence. CONCLUSIONS: Medication adherence was affected by many factors. Special attention and interventions should be given to women taking tamoxifen in the 2nd to 3rd year of medication, and aromatase inhibitors in the 1st to 2nd year. Further prospective design studies are needed to explore effective measures to improve medication adherence of women with breast cancer treated by endocrine therapy.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/psicología , Cumplimiento de la Medicación/psicología , Cumplimiento de la Medicación/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/patología , Estudios Transversales , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Pronóstico
4.
Biores Open Access ; 1(5): 247-51, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23516672

RESUMEN

Due to lack of blood vessel systems, only a few tissues, such as skin, cartilage, and cornea, have been successfully constructed in vivo. Anticoagulative scaffolds have been used in drug-eluting stent systems both in animal studies and clinical therapies, as in the medicinal leech therapy used to salvage venous-congested microvascular free flaps improved perfusion inspired us to tackle this hurdle in bone tissue engineering. We hypothesize that a combination of bone marrow as the blood supply and a heparin/chitosan-coated acellular bone matrix that acts like hirudin, together with a vacuum-assisted closure therapy system, would provide blood perfusion to the scaffold. Using these methods, a biomimetically engineered bone construct would facilitate clinical translation in bone tissue engineering and offer new therapeutic strategies for reconstructing large bone defects if the hypothesis proves to be practical.

5.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 29(1): 97-8, 2004 Feb.
Artículo en Chino | MEDLINE | ID: mdl-16137019

RESUMEN

OBJECTIVE: To investigate the influence of obstructive sleep apnea-hypopnea syndrome (OSAHS) on the QTc interval. METHODS: By the polysomnograph,98 patients were divided into an obstructive sleep apnea-hypopnea syndrome group and a control group. We tested their 24 hour DCG and observed the difference of the heart rate,QT interval and QTc interval at the same time. RESULTS: We compared the heart rate (76 +/- 10 bt/min), QT interval (366 +/- 30 ms), and QTc interval (404 +/- 45 ms) with those of the control group (73 +/- 96 bt/min, 342 +/- 31 ms, 374 +/- 30 ms, respectively). The QT interval and QTc interval significantly differred (P < 0.05). CONCLUSION: The QT interval and QTc interval in the OSAHS group has been prolonged, suggesting OSAHS might be a high risk factor in arrhythmia and sudden death.


Asunto(s)
Electrocardiografía Ambulatoria , Frecuencia Cardíaca , Apnea Obstructiva del Sueño/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Arritmias Cardíacas/etiología , Muerte Súbita Cardíaca/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polisomnografía , Factores de Riesgo , Apnea Obstructiva del Sueño/complicaciones
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