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1.
Opt Express ; 28(2): 936-947, 2020 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-32121813

RESUMEN

The integral representation of the Zernike radial functions is well approximated by applying the Riemann sums with a surprisingly rapid convergence. The errors of the Riemann sums are found to averagely be not exceed 3 ×10-14, 3.3×10-14, and 1.8×10-13 for the radial order up to 30, 50, and 100, respectively. Moreover, a parallel algorithm based on the Riemann sums is proposed to directly generate a set of radial functions. With the aid of the graphics processing units (GPUs), the algorithm shows an acceleration ratio up to 200-fold over the traditional CPU computation. The fast generation for a set of Zernike radial polynomials is expected to be valuable in further applications, such as the aberration analysis and the pattern recognition.

2.
Opt Lett ; 44(4): 959-962, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30768030

RESUMEN

A general integral formula is analytically derived to represent the wave function of elliptical vortex modes. The derived formula can be straightforwardly employed to take account of spatial damping to explore vortex structure. Spatial damping is found to cause the central degenerate singularity of the circular vortex mode to be split into several singularities with different topological charges. For the non-circular vortex beam, the influence of spatial damping on the distribution of singularities is not significant. Theoretical analyses are confirmed to agree very well with the experimental measurements.

3.
Opt Lett ; 44(8): 2028-2031, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-30985802

RESUMEN

An analytical wave representation is derived to express the asymmetric elliptic vortex beams generated by using an astigmatic mode converter to transform the asymmetric Hermite-Gaussian modes. The effect of the spatial asymmetry on the elliptic vortex beam can be straightforwardly considered in the analytical wave representation. A detailed comparison with experimental intensity patterns and phase structures is made. The good agreement between experimental results and theoretical analyses confirms the characterization and generation of the asymmetric elliptic vortex beams.

4.
Opt Express ; 26(24): 31738-31749, 2018 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-30650755

RESUMEN

We employ an off-axis pumped Nd:YVO4 laser and control the reflectance of output coupler to directly generate asymmetrical Hermite-Gaussian (HG) modes with various transverse orders. By using an astigmatic mode converter, the generated asymmetrical HG modes are straightforwardly transformed into asymmetrical Laguerre-Gaussian (LG) modes with a crescent-like shape. The average output power of all the crescent-shaped LG modes can exceed 1W at the pump power of 4W. Furthermore, experimental results are theoretically verified by resonant modes derived from the inhomogeneous Helmholtz equation with the localized source distribution. Theoretical resonant modes are also used to explore the dependence of the phase structures of LG modes on the system loss. As the loss increases, it is found that the singularities at the origin will be rearranged and new singularities are formed in the outside region with average orbital angular momentum remaining unchanged.

5.
Opt Express ; 26(16): 20481-20491, 2018 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-30119358

RESUMEN

The generalized geometric mode with several high-order Hermite-Gaussian (HG) beams localized on ray periodic orbits in the degenerate resonator is generated by an off-axis pumped Nd:YVO4 laser, by performing beam transformation via an astigmatic mode converter, the generalized geometric modes are found that can be converted into the multi-axis vortex beams with the bundled-rings structures. Experimental results reveal that the generated multi-axis vortex beams can preserve quite stable beam structures even under high-power operation. Moreover, the radius of the bundled rings for the multi-axis vortex beams can be flexibly adjusted by the off-axis pumping to lead to vortex structures with easily controlled orbital angular momentum distribution. The good agreement between the experimental and theoretical results of propagation evolution for the astigmatic transformation of generalized geometric modes further verify the feasibility of using the proposed system to realize various high-powered, multi-center vortex beams with good reliability and predictability.

6.
Eur J Cancer Care (Engl) ; 27(2): e12710, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28488375

RESUMEN

The purpose of this study was to determine factors associated with self-perceived body image in female patients with head and neck cancer (HNC), and factors associated with healthcare professional's rating of disfigurement, as well as the correlation between patient and observer ratings. This cross-sectional study recruited 105 women with HNC at a large medical centre. Measures of facial disfigurement and body image, as well as demographic and clinical characteristics, were collected. Multivariate multiple linear regression modelling was used to identify factors associated with healthcare professional's rating of disfigurement and patient self-perceived body image. Disfigurement ratings by healthcare professionals were positively associated with patient self-perceived body image. Medical treatment, cancer stage, radiation dose and cancer site were significantly associated with disfigurement. Medical treatment was an important predictor of perceived body image. These findings indicate a moderate prevalence of disfigurement among women with HNCs. Patients with more disfigurement were more likely to have dissatisfaction with their body image. Nursing professionals need to carefully assess the appearance of women with HNC. Camouflage interventions can be used to help appropriately cope with the disfigurement, and to achieve improved satisfaction with their body image.


Asunto(s)
Actitud del Personal de Salud , Imagen Corporal , Neoplasias de Cabeza y Cuello/psicología , Satisfacción del Paciente , Adulto , Anciano , Estudios Transversales , Cara , Femenino , Humanos , Persona de Mediana Edad , Autoimagen , Adulto Joven
7.
Zhonghua Fu Chan Ke Za Zhi ; 53(7): 481-486, 2018 Jul 25.
Artículo en Zh | MEDLINE | ID: mdl-30078258

RESUMEN

Objective: To study the effect of lentivirus-mediated microRNA (miR) -1246 RNA interference (RNAi) on biological characteristics and behaviors in cervical cancer cells as well as to identify the downstream signaling pathways affected. Methods: MiR-1246 specific cDNA was synthesized and cloned into the recombinant lentiviral vector (LV-miR-1246-inhibitor) . The SiHa cells were devided into three groups: no viral infection (negative control, NC) , infection with control virus (LV-NC) , and infection with miR-1246-inhibitor virus (LV-miR-1246-inhibitor) . The expression of the miR-1246 was detected by reverse transcription (RT) -PCR. Cell growth was analyzed by cell counting kit 8 (CCK-8) assay. The invasion was dectected by transwell matrige gel. Cell apoptosis was detected by flow cytometer. The growth of xenograft tumors was also investigated. Expression of thrombospondin-2 (THBS2) , matrix metalloproteinase (MMP) 2, 9 were also evaluated in the cells. Results: (1) The expression level of miR-1246 in SiHa cells (0.11±0.13) was significantly lower in group LV-miR-1246-inhibitor than those in the group LV-NC and the group NC (1.14±0.86 and 1.30±0.73, respectively; P<0.01) . (2) The proliferation of SiHa was also markedly suppressed in CCK-8 at 96 hours (P<0.01) . (3) The number of group LV-miR-1246-inhibitor was significantly less than those in the LV-NC and NC groups in transwell invasion assay (71±4, 162±5 and 188±5, respectively; P<0.01) . (4) The apoptosis rate of SiHa cells in the group LV-miR-1246-inhibitor [ (16.10±3.37) %] was significantly lower than those of group LV-NC and group NC [ (5.67±0.89) % and (1.78±0.08) %,P<0.01]. (5) The tumor volume in the nude mice group LV-miR-1246-inhibitor [ (287±59) mm(3)] was significantly lower than those in the LV-NC and NC groups [ (571±137) and (657±144) mm(3), respectively; P<0.01]. (6) Compared with the LV-NC group and the NC group, THBS2 protein expression in the tumor tissue of the nude mice in the group LV-miR-1246-inhibitor was significantly increased (P<0.05) , while the expression levels of MMP-2 and MMP-9 protein were significantly decreased (P<0.01) . Conclusion: These results suggest that miR-1246 functions during cervical cancer pathogenesis and tumor formation via the THBS2, MMP signaling pathway.


Asunto(s)
Apoptosis/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Lentivirus/genética , MicroARNs/genética , Neoplasias del Cuello Uterino/genética , Animales , Ciclo Celular , Línea Celular Tumoral , Femenino , Humanos , Metaloproteinasa 2 de la Matriz , Metaloproteinasa 9 de la Matriz , Ratones , Ratones Desnudos , MicroARNs/metabolismo , Interferencia de ARN , Reacción en Cadena en Tiempo Real de la Polimerasa , Transducción de Señal , Trombospondinas , Transfección , Neoplasias del Cuello Uterino/patología , Cicatrización de Heridas/genética
8.
Eur J Cancer Care (Engl) ; 25(3): 440-8, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-25495287

RESUMEN

The aims of the study were to: (1) examine levels of trismus, xerostomia and nutritional status; (2) compare levels of trismus, xerostomia and nutritional status in patients with nasopharyngeal carcinoma (NPC) receiving different types of radiation modalities; and (3) identify factors related to NPC survivors' risk status for malnutrition and existing malnutrition. A cross-sectional study with consecutive sampling was conducted. NPC survivors were recruited from otolaryngology/oncology outpatient clinics in a medical centre in Northern Taiwan. Study measures included (1) Mandibular Function Impairment Questionnaire, (2) Xerostomia Questionnaire, (3) Mini Nutrition Assessment, (4) Hospital Anxiety and Depression Scale - Depression subscale, and (5) Symptom Severity Scale. A total of 110 subjects were recruited. Those receiving intensity-modulated radiation therapy had less trismus and xerostomia than patients receiving two-dimensional radiation therapy. Patients with female gender, advanced stage, completion of treatments within 1 year, higher levels of depression, more severe trismus and higher symptom severity tended to have malnutrition or were at risk of malnutrition. Trismus and xerostomia are long-term problems in some NPC survivors and may contribute to malnutrition. To better manage a patient's trismus and xerostomia and to enhance nutritional status, clinicians should develop a patient-specific care programme based on careful assessment and targeted measures to improve oral function and insure adequate nutritional intake.


Asunto(s)
Neoplasias Nasofaríngeas/radioterapia , Estado Nutricional/efectos de la radiación , Trismo/etiología , Xerostomía/etiología , Carcinoma , Estudios Transversales , Trastorno Depresivo/etiología , Femenino , Indicadores de Salud , Humanos , Masculino , Desnutrición/etiología , Persona de Mediana Edad , Carcinoma Nasofaríngeo , Radioterapia/efectos adversos , Radioterapia de Intensidad Modulada/efectos adversos
9.
Gene Ther ; 22(2): 155-62, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25354682

RESUMEN

Replicating virus vectors are attractive tools for anticancer gene therapy, but the potential for adverse events due to uncontrolled spread of the vectors has been a major concern. To design a tumor-specific retroviral replicating vector (RRV), we replaced the U3 region of the RRV ACE-GFP with a regulatory sequence consisting of the hepatitis B virus enhancer II (EII) and human α-fetoprotein (AFP) core promoter to produce ACE-GFP-EIIAFP, a hepatocellular carcinoma (HCC)-targeting RRV. Similar to ACE-GFP, ACE-GFP-EIIAFP exhibited robust green fluorescent protein (GFP) expression in HCC cells and, most importantly, it exhibited HCC-specific replication and did not replicate in non-HCC tumor cells or normal liver cells. We sequenced the promoter region of ACE-GFP-EIIAFP collected from serial infection cycles to examine the genomic stability of the vector during its replicative spread, and found that the vector could retain the hybrid promoter in the genome for at least six infection cycles. In vitro studies revealed that ACE-CD-EIIAFP and ACE-PNP-EIIAFP, which express the yeast cytosine deaminase and Escherichia coli purine nucleoside phosphorylase, respectively, exert a highly potent cytotoxic effect on HCC cells in the presence of their respective prodrugs. In vivo, ACE-CD-EIIAFP-mediated suicide gene therapy efficiently suppressed HCC tumor growth and no detectable RRV signal was observed in extratumoral tissues. These results suggest that the tumor-specific, suicide-gene-encoding RRV may fulfill the promise of retroviral gene therapy for cancer.


Asunto(s)
Carcinoma Hepatocelular/terapia , Virus de la Leucemia Murina/genética , Neoplasias Hepáticas Experimentales/terapia , Animales , Secuencia de Bases , Carcinoma Hepatocelular/genética , Terapia Genética , Vectores Genéticos , Inestabilidad Genómica , Proteínas Fluorescentes Verdes/biosíntesis , Proteínas Fluorescentes Verdes/genética , Células HEK293 , Células Hep G2 , Humanos , Neoplasias Hepáticas Experimentales/genética , Células MCF-7 , Ratones Endogámicos BALB C , Ratones Desnudos , Datos de Secuencia Molecular , Trasplante de Neoplasias , Regiones Promotoras Genéticas , Secuencias Repetidas Terminales , Transcripción Genética , Replicación Viral , alfa-Fetoproteínas/genética , alfa-Fetoproteínas/metabolismo
10.
Colorectal Dis ; 16(4): 259-64, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24118729

RESUMEN

AIM: High-risk patients with Stage II colon cancer may benefit from adjuvant chemotherapy, but it is difficult to identify such a patient group. A robust and reproducible index would be helpful to select the subset of Stage II colon cancer patients at high risk. This study investigated the potential prognostic significance of tumour budding in Stage II colon cancer. METHOD: In all, 135 Stage II colon cancer patients with known outcome were identified. The degree of tumour budding was assessed by two individual observers and was classified, according to the number of tumour buds in the area with the greatest budding intensity on haematoxylin and eosin slides, as high-grade budding (10 or more tumour buds) and low-grade budding (0-9 buds). Inter-observer agreement for two observers was assessed by using the kappa test. Progression-free and cancer-specific survivals were analysed using the Kaplan-Meier method and Cox regression. RESULTS: The 5-year progression-free survival rates for patients with high-grade tumour budding (n = 36) and those with low-grade budding (n = 99) were 57.6% and 89.0% (P < 0.001). The 5-year cancer-specific survival rates were 66.7% vs 92.0% (P < 0.001). Cox regression analyses demonstrated tumour budding as an independent predictor of disease progression (hazard ratio 4.982, P < 0.001) and cancer-related death (hazard ratio 4.142, P = 0.003). The two observers agreed on the classification of tumour budding in 118 cases (87.4%) and the inter-observer agreement was good (κ = 0.692). CONCLUSION: Tumour budding is a strong and reproducible prognostic factor for adverse outcome in Stage II colon cancer, which may serve as a prognostic marker to identify patients with a high risk of recurrence who may benefit from adjuvant therapy.


Asunto(s)
Carcinoma/patología , Neoplasias del Colon/patología , Recurrencia Local de Neoplasia/patología , Medición de Riesgo , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Adulto Joven
11.
Horm Metab Res ; 45(1): 38-42, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22956307

RESUMEN

The present study was designed to investigate the role of TNF-α in renal damage observed in mice with hepatic steatosis. We induced hepatic steatosis in mice using high fat diet and treated mice with ectanercept at the dose sufficient to block TNF-α receptors or vehicle for 1 month. Plasma TNF-α, total cholesterol (TC), triglyceride (TG), LDL-cholesterol (LDL-C), and HDL-cholesterol (HDL-C) were determined at the end of this treatment. Renal damage was identified by histologic observation and the higher of serum blood urea nitrogen (BUN) and creatinine. Also, changes of PPAR-δ in kidney and renal mesangial cell (RMC) were analyzed using Western blot. Plasma TNF-α was markedly raised in mice showing hepatic steatosis. However, the levels of blood lipids (TC, TG, HDL-C, and LDL-C) and TNF-α were not modified by the treatment of etanercept although the hepatic steatosis has been improved. Etanercept shows renal protection from histological identification and recovery of serum BUN and creatinine levels. Moreover, restoration of PPAR-δ expression by etanercept was observed in mice kidney. Direct effect of TNF-α on PPAR-δ expression was also characterized in RMC cell. We suggest that renal damage in mice with hepatic steatosis is mainly induced by increase of TNF-α through the decrease of renal PPAR-δ. Etanercept could block TNF-α receptors to restore PPAR-δ and improve renal function in mice with hepatic steatosis.


Asunto(s)
Hígado Graso/metabolismo , Hígado Graso/patología , Riñón/metabolismo , Riñón/patología , Factor de Necrosis Tumoral alfa/metabolismo , Acridinas/metabolismo , Animales , Nitrógeno de la Urea Sanguínea , Creatinina/sangre , Dieta Alta en Grasa , Etanercept , Hígado Graso/sangre , Hígado Graso/fisiopatología , Inmunoglobulina G/farmacología , Riñón/efectos de los fármacos , Riñón/fisiopatología , Pruebas de Función Renal , Lípidos/sangre , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Hígado/fisiopatología , Masculino , Ratones , Ratones Endogámicos C57BL , PPAR delta/metabolismo , Ratas , Especies Reactivas de Oxígeno/metabolismo , Receptores del Factor de Necrosis Tumoral , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
12.
J Nutr Health Aging ; 26(3): 307-313, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35297475

RESUMEN

BACKGROUND: Chondroitin sulfate (CS) is found in humans' cartilage, bone, cornea, skin, and arterial wall. It consists of the foundation substance in the extracellular matrix (ECM) of connective tissue. The oral supplement form of CS is clinically used in treating osteoarthritis (OA). METHODS: Cell migration was observed by the transwell assay. The EMT, Akt/IKK/IκB pathways, TIMPs, collagen and MMPs in cell lysate were determined by Western blotting. The expression of MMP activity was determined by gelatin zymography. The production of reactive oxygen species (ROS) was determined by using a fluorescence spectrophotometer. RESULTS: In the current report, we demonstrated that CS can increase the cell proliferation and migration of chon-001 chondrocytes. Treatment with CS induced the epithelial-mesenchymal transition and increased the expression of type II collagen and TIMP-1/TIMP2 and inhibited the expressions and activities of metalloproteinase-9 (MMP-9) and metalloproteinase-2 (MMP-2). The phosphorylation of Akt, IκB kinase (IKK), IκB and p65 was decreased by CS. CS treatment resulted in ß-catenin production and XAV939, a ß-catenin inhibitor, and inhibited the cell proliferation by CS treatment. In addition, also significantly induced intracellular ROS generation. Treatment with antioxidant propyl gallate blocked cell migration induced by CS. CONCLUSION: We demonstrated that CS induced cell proliferation and migration of chondrocytes by inducing ß-catenin and enhancing ROS production. Moreover, our studies demonstrated that CS can increase the activity of chondrocytes and help patients with osteoarthritis to restore cartilage function.


Asunto(s)
Condrocitos , Osteoartritis , Proliferación Celular , Células Cultivadas , Condrocitos/metabolismo , Sulfatos de Condroitina/metabolismo , Sulfatos de Condroitina/farmacología , Humanos , Interleucina-1beta/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , FN-kappa B/metabolismo , Osteoartritis/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Especies Reactivas de Oxígeno/metabolismo , beta Catenina/metabolismo
13.
Sci Adv ; 6(10): eaaz3180, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32181365

RESUMEN

Strain-sensitive Ba x Sr1-x TiO3 perovskite systems are widely used because of their superior nonlinear dielectric behaviors. In this research, new heterostructures including paraelectric Ba0.5Sr0.5TiO3 (BSTO) and ferroelectric BaTiO3 (BTO) materials were epitaxially fabricated on flexible muscovite substrate. Through simple bending, the application of mechanical force can regulate the dielectric constant of BSTO from -77 to 36% and the channel current of BTO-based ferroelectric field effect transistor by two orders. The detailed mechanism was studied through the exploration of phase transition and determination of band structure. In addition, the phase-field simulations were implemented to provide theoretical support. This research opens a new avenue for mechanically controllable components based on high-quality oxide heteroepitaxy.

14.
Int J STD AIDS ; 20(2): 115-8, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19182058

RESUMEN

Information on the prevalence and incidence of sexually transmitted infections is important for developing prevention and control strategies and allocating human and financial resources. However, there are no available estimates of such information for many areas in China. In this study, we used the existing data to make a preliminary estimation of syphilis infections in Shenzhen city, in south-eastern China. Data on prevalence rates of syphilis infections among different populations were obtained from the local HIV/sexually transmitted disease second-generation surveillance programme, and the sizes of different populations were estimated based on the most recently available figures. It was estimated that 83,760 (range 77,490-90,020) people are currently infected with syphilis, giving a prevalence of 0.71-0.82% (0.76% on average) in Shenzhen. Around 18% of these syphilis infections occur among men who have sex with men and another 15.8% and 8.7% occur among female sex workers and their clients, respectively. These estimates suggest that a combination of unprotected paid sex and sex between men may be sustaining the epidemic of syphilis in the study area. The preliminary estimates will assist the government in planning and improving its comprehensive intervention programmes for the future control and prevention of syphilis.


Asunto(s)
Brotes de Enfermedades , Vigilancia de la Población/métodos , Enfermedades de Transmisión Sexual/epidemiología , Sífilis/epidemiología , China/epidemiología , Femenino , Homosexualidad Masculina , Humanos , Masculino , Prevalencia , Asunción de Riesgos , Trabajo Sexual , Conducta Sexual , Enfermedades de Transmisión Sexual/prevención & control , Sífilis/prevención & control , Sexo Inseguro
15.
Intern Med J ; 39(11): 728-32, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19226422

RESUMEN

BACKGROUND: Drug promotion is one of the main factors that influence prescribing practices, but there are limited data available to quantify the relationship between drug advertising and prescription sales. AIM: To investigate the relationship between advertising for antihypertensive medicines and prescription sales in Australia between 1993 and 2002. METHODS: Retrospective observational study. Advertising trends were monitored by counting the number of advertisements published in three Australian medical journals. Monthly prescription dispensing data were obtained from Drug Utilisation Sub-Committee and expressed as numbers of defined daily doses/1000 inhabitants/day. Linear regression and cross-correlations of time series were used in the analysis. RESULTS: The drug classes the most heavily advertised, angiotensin-converting enzyme inhibitors and calcium channel blockers, were also the most prescribed during the study period, while the drugs the least advertised, thiazide diuretics and beta-blockers, were the least used. In 5 of the 7 main antihypertensive classes, the product the most advertised was also the most prescribed. Other factors, such as the publication of large clinical trials, may have also influenced prescribing patterns. CONCLUSION: Prescription sales of antihypertensives in Australia are correlated with promotional advertising. The newest and most expensive medicines may be chosen over older effective drugs by prescribers. New policies on drug promotion control need to be developed.


Asunto(s)
Publicidad/economía , Publicidad/tendencias , Antihipertensivos/economía , Prescripciones de Medicamentos/economía , Antihipertensivos/uso terapéutico , Australia , Humanos , Estudios Retrospectivos
16.
Opt Express ; 16(4): 2415-22, 2008 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-18542320

RESUMEN

In this paper, we describe a thermal embossing imprint method, which we name "nano-imprinting in metal" (NIM), for patterning metal films with a variety of profiles. Metal films exhibiting either perforated hole-arrays or corrugated structures with various surface morphologies can be fabricated rapidly. The SPR phenomenon allowed energy coupling to the other side of the textured metal film, causing a dramatic increase in the transmission. As a technique for readily controlling the working wavelength and transmittance, the NIM method has great potential for application in various optoelectronic devices.

17.
Sci Rep ; 8(1): 10844, 2018 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-30022128

RESUMEN

Point-driven modern Chladni figures subject to the symmetry breaking are systematically unveiled by developing a theoretical model and making experimental confirmation in the orthotropic brass. The plates with square shape are employed in the exploration based on the property that the orientation-dependent elastic anisotropy can be controlled by cutting the sides with a rotation angle with respect to the characteristic axes of the brass. Experimental results reveal that the orientation symmetry breaking not only causes the redistribution of resonant frequencies but also induces more resonant modes. More intriguingly, the driving position in some of new resonant modes can turn into the nodal point, whereas this position is always the anti-node in the isotropic case. The theoretical model is analytically developed by including a dimensionless parameter to consider the orientation symmetry-breaking effect in a generalized way. It is numerically verified that all experimental resonant frequencies and Chladni patterns can be well reconstructed with the developed model. The good agreement between theoretical calculations and experimental observations confirms the feasibility of using the developed model to analyze the modern Chladni experiment with orientation symmetry breaking. The developed model is believed to offer a powerful tool to build important database of plate resonant modes for the applications of controlling collective motions of micro objects.

18.
Zhonghua Shao Shang Za Zhi ; 34(7): 476-480, 2018 Jul 20.
Artículo en Zh | MEDLINE | ID: mdl-30060350

RESUMEN

Objective: To explore mechanism of lung injury of rats induced by inhalation of white smoke from burning smoke pot. Methods: Forty-eight Sprague Dawley rats were divided into control group (n=12) and injury group (n=36) according to the random number table. Rats in injury group were placed in smoke-induced injury experimental equipment fulled with white smoke from burning smoke pot for 5 minutes to make lung injury, and rats in control group were placed in smoke-induced injury experimental equipment fulled with air for 5 minutes to make sham injury. Six rats in injury group at post injury hour (PIH) 6, 24, and 72 and six rats in control group at PIH 72 were collected to observe pathological changes of lung tissue and pathological score of rats in the two groups by hematoxylin-eosin staining, to detect expression of nuclear factor-κB (NF-κB) p65 mRNA in lung tissue of rats by reverse transcriptional polymerase chain reaction, and to detect content of tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß), and IL-6 in lung tissue of rats by enzyme-linked immunosorbent assay. Data were processed with one-way analysis of variance and t test. Results: At PIH 72, lung tissue structure of rats in control group was clear and complete, with no inflammatory cell infiltration. At PIH 6, there was edema, hemorrhage, and inflammatory cell infiltration in lung tissue of rats in injury group. At PIH 24, edema, hemorrhage, and inflammatory cell infiltration in lung tissue of rats in injury group aggravated. At PIH 72, area of edema in lung tissue of rats in injury group was enlarged, with obvious hemorrhage and inflammatory cell infiltration. At PIH 6, 24, and 72, pathological score of lung tissue of rats in injury group was (3.43±0.86), (5.39±0.93), and (9.99±0.84) points, respectively, obviously higher than that of rats in control group at PIH 72 [(2.11±0.20) points, t=3.659, 8.450, 22.355, P<0.05]. As time post injury prolonged, pathological scores of lung tissue of rats in injury group were significantly increased (F=121.244, P<0.01). At PIH 6, 24, and 72, expression of NF-κB p65 mRNA in lung tissue of rats in injury group was 15.5±4.3, 25.9±1.8, 30.9±3.5 respectively, significantly higher than that of rats in control group at PIH 72 (7.8±0.8, t=4.315, 20.445, 14.408, P<0.01). As time post injury prolonged, expression of NF-κB p65 mRNA in lung tissue of rats in injury group gradually increased (F=32.691, P<0.01). At PIH 6, 24, and 72, content of TNF-α, IL-1ß, and IL-6 in lung tissue of rats in injury group was significantly higher than that of rats in control group at PIH 72, respectively (t=7.650, 8.968, 6.827, 6.726, 8.978, 3.460, 5.420, 13.289, 16.438, P<0.01). At PIH 24, content of TNF-α and IL-1ß in lung tissue of rats in injury group was higher than that of rats in the same group at PIH 6 and 72, respectively (t=3.409, -2.549, 4.047, -4.100, P<0.05). At PIH 24 and 72, content of IL-6 in lung tissue of rats in injury group was respectively higher than that of rats in the same group at PIH 6 (t=8.273, 9.711, P<0.05). Conclusions: After inhaling white smoke from burning smoke pot, rats are inflicted with lung injury by increasing expression of NF-κB p65 mRNA and content of TNF-α, IL-1ß, and IL-6, and induce pathological changes of edema, hemorrhage, and inflammatory cell infiltration of lung tissue.


Asunto(s)
Lesión Pulmonar/inducido químicamente , Pulmón/fisiopatología , Lesión por Inhalación de Humo , Animales , Edema , Ensayo de Inmunoadsorción Enzimática , Interleucina-1beta , Lesión Pulmonar/complicaciones , FN-kappa B , Ratas , Ratas Sprague-Dawley , Humo , Factor de Necrosis Tumoral alfa
19.
Clin Nephrol ; 66(1): 25-31, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16878432

RESUMEN

OBJECTIVE: Parathyroid cells synthesize and release endothelin-1 (ET-1). ET-1 displays an in vitro inhibitory effect on basal parathyroid hormone (PTH) secretion and also counteracts PTH hypersecretion stimulated by low calcium. Such effects are further demonstrated in vivo, independent of the changes in calcitonin. We propose that ET-1 may regulate the pathogenesis of uremic hyperparathyroidism. However, this was not directly demonstrated in human parathyroid glands. DESIGN: Hyperplastic parathyroid glands are obtained from the surgical operation for uremic hyperparathyroidism. Cells are isolated by enzyme digestion and treated with ET-1, and are assessed for PTH mRNA expression. PTH in the plasma and the medium is measured by a newly developed method to detect the whole PTH (1-84). PATIENTS: Uremic patients with severe secondary hyperparathyroidism and ultrasonography-proved hypertrophy of parathyroid glands received elective surgical approaches under general anesthesia. The resected glands were immediately taken to the laboratory for fresh isolation. MEASUREMENTS: Following ET-1 treatment, PTH mRNA expression is evaluated by RT-PCR method. ET-1 is detected with radioimmunoassay kit and PTH is measured by a new commercially available Duo PTH kit. RESULTS: ET-1 exhibited a dose-dependent inhibitory effect (from 10(-12) - 10(-7) M) on PTH mRNA expression of parathyroid cells, either in the basal or in the low-calcium-stimulated states. Release of PTH into the medium is also gradually inhibited by the increase in ET-1 concentrations. CONCLUSIONS: Our results demonstrate that ET-1 attenuates PTH mRNA expression in freshly isolated human parathyroid cells, and PTH release is also decreased. This result is consistent with our previously reported in vitro and in vivo experiments.


Asunto(s)
Endotelina-1/farmacología , Glándulas Paratiroides/efectos de los fármacos , Glándulas Paratiroides/fisiología , Hormona Paratiroidea/genética , Hormona Paratiroidea/metabolismo , Adulto , Secuencia de Bases , Cartilla de ADN/genética , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Técnicas In Vitro , Masculino , Persona de Mediana Edad , Glándulas Paratiroides/citología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
20.
Clin Nephrol ; 66(4): 240-6, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17063990

RESUMEN

AIMS: We previously reported 2 hemodialysis (HD) patients with recurrent infections and selective immunoglobulin A deficiency (IgAD). We further demonstrated that serum IgA levels were lower and the prevalence of IgAD was higher in uremic patients. The exact mechanisms of IgAD in uremic patients largely remained unclear. In some patients, it was caused by anti-IgA antibody neutralization and subsequent destruction. We performed the present study to survey if there is any defect in IgA production. MATERIALS AND METHODS: 288 patients were initially included for examination of serum immunoglobulins. 16 normal persons, 16 dialysis patients without IgAD, and 12 dialysis patients with IgAD were enrolled after the initial examination. Blood was drawn into heparinized tubes. WBC counts and lymphocyte percentage were examined by a CBC counter. Lymphocytes were separated by the Ficoll-Paque method. Flow cytometry was utilized to isolate the B cell and IgA-secreting B cell after staining with CD 19 phycoerythrin and FITC-conjugated rabbit anti-human IgA antibody. RESULTS: There is no significant difference between WBC counts or total lymphocyte counts of these 3 groups. However, we found a lower percentage of total lymphocyte counts in dialysis patients, either with or without IgAD. The total B cell numbers were lower in dialysis patients with IgAD. In addition, there were fewer IgA-secreting B cells in dialysis patients with IgAD. CONCLUSION: Decreased B cell and IgA-secreting B cell counts are seen in uremic patients with IgAD. This, in turn, indicates that there might be a defect of IgA production in some patients, rather than IgA destruction by anti-IgA antibodies as seen in some other patients. Further study is needed to investigate the mechanisms of decreased B cells and IgA-secreting B cells.


Asunto(s)
Linfocitos B/metabolismo , Diálisis/efectos adversos , Deficiencia de IgA/etiología , Inmunoglobulina A/sangre , Adulto , Anciano , Linfocitos B/citología , Femenino , Humanos , Deficiencia de IgA/epidemiología , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Prevalencia
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