Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
Sensors (Basel) ; 24(16)2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39205043

RESUMEN

Vibration sensors are widely used in many fields like industry, agriculture, military, medicine, environment, etc. However, due to the speedy upgrading, most sensors composed of rigid or even toxic materials cause pollution to the environment and give rise to an increased amount of electronic waste. To meet the requirement of green electronics, biodegradable materials are advocated to be used to develop vibration sensors. Herein, a vibration sensor is reported based on a strategy of pencil-drawing graphite on paper. Specifically, a repeated pencil-drawing process is carried out on paper with a zigzag-shaped framework and parallel microgrooves, to form a graphite coating, thus serving as a functional conductive layer for electromechanical signal conversion. To enhance the sensor's sensitivity to vibration, a mass is loaded in the center of the paper, so that higher oscillation amplitude could happen under vibrational excitation. In so doing, the paper-based sensor can respond to vibrations with a wide frequency range from 5 Hz to 1 kHz, and vibrations with a maximum acceleration of 10 g. The results demonstrate that the sensor can not only be utilized for monitoring vibrations generated by the knuckle-knocking of plastic plates or objects falling down but also can be used to detect vibration in areas such as the shield cut head to assess the working conditions of machinery. The paper-based MEMS vibration sensor exhibits merits like easy fabrication, low cost, and being environmentally friendly, which indicates its great application potential in vibration monitoring fields.

2.
Cell Biochem Funct ; 35(5): 254-259, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28749078

RESUMEN

The mechanism of pituitary gland tumour (PGT) is unclear. Aberrant immune tolerance is associated with the pathogenesis of tumour. Vitamin D and vitamin D receptor (VDR) are involved in the immune regulation. Interleukin (IL)-10 is one of the important immune regulatory molecules. This study aims to elucidate the role of VDR in the regulation of IL-10 in peripheral B cells of PGT patients. In this study, the peripheral blood samples were collected from PGT patients and healthy subjects. B cells were purified from the blood samples and analysed by RT-qPCR and Western blotting. The correlation between the expression of IL-10 and VDR in the B cells was assessed. We observed that the serum VitD levels were negatively correlated with IL-10 expression in peripheral B cells of patients with PGT. Low levels of VDR expression were found in peripheral B cells of PGT patients. Exposure to VitD suppressed the expression of IL-10 in B cells. The VDR bounds the transcription factor of IL-10 to interfere with the expression of IL-10 in B cells. The VDR agonists inhibited IL-10 expression in B cells from PGT patients. In conclusion, modulation of the expression of VDR can regulate the expression of IL-10 in peripheral B cells of PGT patients, which may contribute to the treatment of PGT.


Asunto(s)
Linfocitos B/metabolismo , Interleucina-10/genética , Neoplasias Hipofisarias/genética , Receptores de Calcitriol/genética , Adulto , Linfocitos B/patología , Calcitriol/administración & dosificación , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Interleucina-10/biosíntesis , Masculino , Persona de Mediana Edad , Neoplasias Hipofisarias/sangre , Neoplasias Hipofisarias/patología , Receptores de Calcitriol/biosíntesis , Receptores de Calcitriol/sangre , Vitamina D/sangre , Vitamina D/genética , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/genética , Deficiencia de Vitamina D/patología
3.
Chemosphere ; 343: 140215, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37734502

RESUMEN

In the current context of technological and industrial development, strategies for sustainable development and resource utilization have become increasingly important. FW anaerobic fermentation (Fermentation of Wastes) is a process that utilizes organic waste for biotransformation and is widely used for the production of volatile fatty acids (VFAs). Volatile fatty acids (VFAs) are a kind of high value-added product generated from anaerobic fermentation process, and has extensive applications in chemical synthesis and electricity generation. This study investigated the performance of VFAs production from food waste at the presence of alkyl ethoxy polyglycosides (AEG) and sodium dodecyl sulfate (SDS). The highest yield of VFAs was obtained at 0.1 g AEG/g TS (14.53 g COD/L), which increased by 25.80% than the Blank. But inhibited phenomenon was observed at other reactors with relatively low yield and delayed fermentation time. The inhibition of lactate's production and bioconversion delayed the fermentation time, and SDS has changed the acidogenic fermentation type from lactate-butyrate fermentation to acetate fermentation. In addition, more organic matter dissolved in the fermentation liquor with the addition of AEG and SDS, but the hydrolysis and acidification of polysaccharide were inhibited to some extent. Microbial community analysis showed that the abundance of key bacteria Clostridium has significantly decreased from 82.71% (Blank) to 33.54% (AEG) and 23.72% (SDS), leading to low VFAs production performance.

4.
Materials (Basel) ; 14(8)2021 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-33921747

RESUMEN

Mg-Sn-Al alloy is a new type of heat-resistant magnesium alloy with great potential and the hot deformation process of this alloy is of great significance for its application. The microstructure, hot deformation behavior, textural evolution, and processing map of a Mg-8 wt.% Sn-1.5 wt.% Al alloy were studied. A Gleeble 1500 D thermo-mechanical simulator was used. The temperature of deformation was 653 to 773 K, the strain rate was 0.001-1 s-1, and the maximum deformation degree was 60%. The obtained results show that the rheological stress of the alloy decreases with an increase in deformation temperature and increases with an increase in the strain rate. The alloy is completely dynamically recrystallized at 653 K, and the entire structure is formed of homogeneous crystals/grains, with small secondary phase particles distributed at the crystal boundary. The mean apparent activation energy of hot compression deformation is 153.5 kJ/mol. The Mg-8 wt.% Sn-1.5 wt.% Al alloy exhibits excellent plastic deformation properties, an expansive thermal processing interval, and a narrow instability zone under the test temperature and deformation rate. The optimal process parameters of the alloy comprise deformation temperatures between 603 and 633 K and strain rates of 0.03 to 0.005 s-1.

5.
Materials (Basel) ; 14(7)2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33916160

RESUMEN

Precipitate phases in an Mg-7Gd-3Y-2Zn-0.5Zr alloy aged isothermally at 240 °C were examined using high-resolution transmission electron microscopy (TEM) and high-angle annular dark-field scanning TEM. The two types of precipitation sequence that involve Mg-Gd and long period stacking ordered (LPSO) type were found. The LPSO type sequence consisted of the precipitation of γ'', γ', 14H-LPSO/18R-LPSO. The Mg-Gd type precipitation sequence involved the formation of ß'(b.c.o.) and ß1(f.c.c.). The sequence, morphology, distribution, and crystal structure of these precipitates formed during isothermal aging were investigated. The results indicated that the priority precipitation of Mg-Gd and LPSO type sequences during aging can be affected by Nd, which has a higher diffusion coefficient than Gd and Y. The dislocation structures and strengthening mechanism were also discussed.

6.
Materials (Basel) ; 14(7)2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33916176

RESUMEN

Nowadays, wrought zinc-based biodegradable alloys are favored by researchers, due to their excellent mechanical properties and suitable degradation rates. However, there are few research studies on their thermal deformation behavior at present. This study took Zn-1Fe-1Mg and explored its microstructural change, deformation, recrystallization behavior and processing map by means of the thermal simulation experiment, at temperatures ranging from 235 °C to 340 °C and strain rates ranging from 10-2 s-1 to 10 s-1. The constitutive model was constructed using the Arrhenius formula. The results indicated that the evolution of microstructure included the dynamic recrystallization (DRX) of the Zn matrix, the spheroidization of the Mg2Zn11 phase, and breaking of the FeZn13 phase. The subgrains observed within the deformed grain resulted mainly from continuous dynamic recrystallization (CDRX). The precipitated FeZn13 grains overlapped with the precipitated MgZn2 from the matrix, thus forming a spine-like structure at the phase interface. After compression, the alloy possessed a strong basal texture. Affected by the change of Zn twins, textural strength decreased at first and then increased as the deformation temperature rose. There was only a small unstable region in the processing map, indicating that the alloy exhibited good machinability.

7.
Regen Biomater ; 8(1): rbaa047, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33732493

RESUMEN

Biodegradable metals hold promises for bone fracture repair. Their clinical translation requires pre-clinical evaluations including animal studies, which demonstrate the safety and performance of such materials prior to clinical trials. This evidence-based study investigates and analyzes the performance of bone fractures repair as well as degradation properties of biodegradable metals in animal models. Data were carefully collected after identification of population, interventions, comparisons, outcomes and study design, as well as inclusion criteria combining biodegradable metals and animal study. Twelve publications on pure Mg, Mg alloys and Zn alloys were finally included and reviewed after extraction from a collected database of 2122 publications. Compared to controls of traditional non-degradable metals or resorbable polymers, biodegradable metals showed mixed or contradictory outcomes of fracture repair and degradation in animal models. Although quantitative meta-analysis cannot be conducted because of the data heterogeneity, this systematic review revealed that the quality of evidence for biodegradable metals to repair bone fractures in animal models is 'very low'. Recommendations to standardize the animal studies of biodegradable metals were proposed. Evidence-based biomaterials research could help to both identify reliable scientific evidence and ensure future clinical translation of biodegradable metals for bone fracture repair.

8.
Materials (Basel) ; 13(21)2020 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-33137896

RESUMEN

Zinc (Zn), one of the promising candidates for biodegradable implant materials, has excellent biocompatibility and biodegradability. In this study, as-cast Zn1FexMg (x ≤ 1.5 wt %) alloys were prepared to systematically explore the effects of magnesium (Mg) alloying on their microstructures, mechanical properties, and biodegradability. The microstructure of Zn1FexMg alloy consisted of Zn matrix, Zn + Mg2Zn11 eutectic structure, and FeZn13 phase. The addition of Mg not only promoted grain refinement of the alloy, but also improved its mechanical properties. The results of immersion tests showed that the addition of Mg accelerated microcell corrosion between different phases, and the modeling of the corrosion mechanism of alloys in simulated body fluid (SBF) solution was discussed to describe the interaction between different phases in the corrosion process. Zn1Fe1Mg possessed superior comprehensive mechanical properties and appropriate corrosion rate, and the values for hardness, tensile strength, yield strength, elongation, and corrosion rate were 105 HB, 157 MPa, 146 MPa, 2.3%, and 0.027 mm/a, respectively, thus revealing that Zn1Fe1Mg is a preferred candidate for biodegradable implant material.

9.
J Neurosurg ; 108(4): 775-81, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18377258

RESUMEN

OBJECT: The aim of this study was to use diffusion tensor tractography (DTT) to define the 3D relationships of the uncinate fasciculus, anterior commissure, inferior occipitofrontal fasciculus, inferior thalamic peduncle, and optic radiation and to determine the positioning landmarks of these white matter tracts. METHODS: The anatomy was studied in 10 adult human brain specimens. Brain DTT was performed in 10 healthy volunteers. Diffusion tensor tractography images of the white matter tracts in the temporal stem were obtained using the simple single region of interest (ROI) and multi-ROIs based on the anatomical knowledge. RESULTS: The posteroinferior insular point is the anterior extremity of intersection of the Heschl gyrus and the inferior limiting sulcus. On the inferior limiting sulcus, this point is the posterior limit of the optic radiation, and the temporal stem begins at the limen insulae and ends at the posteroinferior insular point. The distance from the limen insulae to the tip of the temporal horn is just one third the length of the temporal stem. The uncinate fasciculus comprises the core of the anterior temporal stem, behind which the anterior commissure and the inferior thalamic peduncle are located, and they occupy the anterior third of the temporal stem. The inferior occipitofrontal fasciculus passes through the entire temporal stem. The most anterior extent of the Meyer loop is located between the anterior tip of the temporal horn and the limen insulae. Most of the optic radiation crosses the postmedian two thirds of the temporal stem. CONCLUSIONS: On the inferior limiting sulcus, the posteroinferior insular point is a reliable landmark of the posterior limit of the optic radiations. The limen insulae, anterior tip of the temporal horn, and posteroinferior insular point may be used to localize the white matter fibers of the temporal stem in analyzing magnetic resonance imaging or during surgery.


Asunto(s)
Amígdala del Cerebelo/anatomía & histología , Corteza Cerebral/anatomía & histología , Procesamiento de Imagen Asistido por Computador/métodos , Lóbulo Temporal/anatomía & histología , Tronco Encefálico/anatomía & histología , Disección/métodos , Lóbulo Frontal/anatomía & histología , Humanos , Imagen por Resonancia Magnética , Terminología como Asunto , Tálamo/anatomía & histología
10.
J Huazhong Univ Sci Technolog Med Sci ; 26(2): 199-201, 210, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16850746

RESUMEN

Histone deacetylase (HDAC1) has a high expression in many cancer cells and curcumin can inhibit the growth of cancer cells. This paper was designed to investigate the expression of HDAC1 of Raji cells and the effect of curcumin on their proliferation and apoptosis. Raji cells were treated with 3.125-50 micromol/L curcumin for 8-48 h and the growth inhibition rates of Raji cells were measured by MTT. The expression of HDAC1 on Raji cells were examined by mRNA, Western blot at 24 h various concertrations (1.6-50 micromol/L). Curcumin could selectively inhibit the proliferation of Raji cells in a dose- and time-dependent manner, with the inhibition rate being 52.47 %-82.18 % (P<0.01). The up-regulation of HDAC1 expression was observed within 24 h after the treatment with curcumin as shown by RT-PCR and Western blot. With the increase of concentration, the expression was down-regulated in a dose- dependent manner. It is concluded that the expression of HDAC1 plays an important role in the proliferation and apoptosis of Raji cells and curcumin can inhibit the growth of Raji cells at various concentrations and promote the apoptosis of Raji cells.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Curcumina/farmacología , Histona Desacetilasas/biosíntesis , Antineoplásicos Fitogénicos/farmacología , Western Blotting , Linfoma de Burkitt/genética , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patología , Medicamentos Herbarios Chinos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Histona Desacetilasa 1 , Histona Desacetilasas/genética , Humanos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
11.
Chin Med J (Engl) ; 122(24): 2945-50, 2009 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-20137479

RESUMEN

BACKGROUND: Breast conserving surgery (BCS) has been the standard surgical procedure for the treatment of early breast cancer. Endoscopic subcutaneous mastectomy (ESM) plus immediate reconstruction with implants is an emerging procedure. The objective of this prospective study was to evaluate the clinical outcomes of these two surgical procedures in our clinical setting. METHODS: From March 2004 to October 2007, 43 patients with breast cancer underwent ESM plus axillary lymph node dissection and immediate reconstruction with implants, while 54 patients underwent BCS. The clinical and pathological characteristics, surgical safety, and therapeutic effects were compared between the two groups. RESULTS: There were no significant differences in the age, clinical stage, histopathologic type of tumor, operative blood loss, postoperative drainage time, and postoperative complications between the two groups (P > 0.05). The postoperative complications were partial necrosis of the nipple and superficial skin flap in the ESM patients, and hydrops in the axilla and residual cavity in the BCS patients. There was no significant difference in the rate of satisfactory postoperative cosmetic outcomes between the ESM (88.4%, 38/43) and BCS (92.6%, 50/54) patients (P > 0.05). During follow-up of 6 months to 4 years, all patients treated with ESM were disease-free, but 3 patients who underwent BCS had metastasis or recurrence -one of these patients died of multiple organ metastasis. CONCLUSIONS: After considering the wide indications for use, high surgical safety, and favorable cosmetic outcomes, we conclude that ESM plus axillary lymph node dissection and immediate reconstruction with implants - the new surgery of choice for breast cancer - warrants serious consideration as the prospective next standard surgical procedure.


Asunto(s)
Neoplasias de la Mama/cirugía , Mastectomía Segmentaria/métodos , Mastectomía Subcutánea/métodos , Procedimientos de Cirugía Plástica/métodos , Adulto , Femenino , Humanos , Mastectomía Segmentaria/efectos adversos , Mastectomía Subcutánea/efectos adversos , Persona de Mediana Edad , Estudios Prospectivos , Procedimientos de Cirugía Plástica/efectos adversos
12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 14(2): 293-7, 2006 Apr.
Artículo en Zh | MEDLINE | ID: mdl-16638200

RESUMEN

The purpose of this study was to investigate the effect of curcumin on proliferation of B-NHL Raji cell line and explore the relationship between this effect and regulatory expression of p300 and HDAC1 transcription. The in vitro cultured Raji cells were treated with curcumin at various concentrations (6.25-50 micromol/L) and at different time points (0, 6, 12, 24 and 48 hours), the inhibitory ratio of cell growth was measured by MTT assay, the cell apoptosis rate was detected by flow cytometry with Annexin V-FITC/PI double staining, the changes of p300 and HDAC1 mRNA expression and protein level in Raji cells were determined by RT-PCR and Western blot. The results showed that the curcumin could inhibit Raji cell proliferation in significant time-and concentration-dependent manners, IC50 at 24 hours was 25 micromol/L; the curcumin could induce apoptosis of Raji cells in concentration-dependent manner, apoptosis rate was 14.38%-61.18%. The curcumin significantly inhibited activity and expression of p300 and HDAC1. At IC50 concentration, expression of p300 and HDAC1 mRNA and protein level decreased with time-dependent manner, difference between tested and control groups was significant (P < 0.05). It is concluded that the curcumin can inhibit proliferation of B-NHL Raji cells and promote apoptosis of those cells. Curcumin can inhibit the activity and expression of the transcriptional co-activator p300 and HDAC1, which may be involved in its pharmacological mechanisms on B lymphoma cells.


Asunto(s)
Antineoplásicos/farmacología , Curcumina/farmacología , Proteína p300 Asociada a E1A/biosíntesis , Histona Desacetilasas/biosíntesis , Linfoma de Células B/metabolismo , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Proteína p300 Asociada a E1A/genética , Histona Desacetilasa 1 , Histona Desacetilasas/genética , Humanos , Linfoma de Células B/patología , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Células Tumorales Cultivadas
13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 13(4): 624-7, 2005 Aug.
Artículo en Zh | MEDLINE | ID: mdl-16129047

RESUMEN

Curcumin is a crucial component of curcuma. Recently more attention has been paid to the effect of curcumin on specific proliferative inhibition and inducing apoptosis of tumor cells. This study was aimed to investigate the anticancer activities of curcumin and its molecular mechanism. Raji cells (lymphoma cell line) were selected as studying targets, peripheral blood mononuclear cells (PBMNC) obtained from healthy donors were separated by Ficoll solution and suspended in RMPI 1640. The inhibition rates of Raji cells and PBMNC after treatment with curcumin at various concentrations and different times were determined by MTT method and were compared. The expressions of caspase 8 and caspase 9 in Raji cells after treatment with curcumin at 25 micromol/L (IC(50)) and for 24 hours were detected by Western blot. The results showed that curcumin could inhibit proliferation of Raji cells in dose-and time-dependent manner. Curcumin could remarkablely enhance the Raji cell apoptosis at 25 micromol/L and 24 hours (P < 0.01), and its effect was dose-dependent and time-selective. Curcumin had no remarkable effect on PBMNC at certain concentrations, which demonstrated that curcumin could selectively inhibit tumor cell proliferation. It is concluded that the expression of caspase 8 and caspase 9 plays an important role in the proliferation and apoptosis of Raji cells, so that curcumin showed inhibitive effect on Raji cells at various concentrations.


Asunto(s)
Apoptosis/efectos de los fármacos , Caspasa 8/metabolismo , Caspasa 9/metabolismo , Curcumina/farmacología , Antineoplásicos Fitogénicos/farmacología , Western Blotting , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Medicamentos Herbarios Chinos/farmacología , Humanos , Concentración 50 Inhibidora , Linfoma/enzimología , Linfoma/patología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA