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1.
BMC Nurs ; 21(1): 171, 2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35768870

RESUMEN

BACKGROUND: Whether knowledge, attitude and practice of nurses on nursing post-stroke dysphagia patients varies between different ranking hospitals is still unknown. This study aimed to compare the knowledge, attitude and practice level of nurses on nursing post-stroke dysphagia patients between iii-A and ii-A hospitals in China. DESIGN: A cross-sectional study design was used. METHODS: Data were collected from eighteen hospitals in Wuhan, Hubei in May-July 2020, and a total of 824 nurses were recruited by convenient sampling. After propensity score matching, 205 participants in iii-A hospitals were matched with 205 participants in ii-A hospitals. RESULTS: There were no statistically differences in the socio-demographic characteristics between two groups after propensity score matching. Before matching, the regression coefficients between hospital ranking and knowledge, attitude, practice were -0.415, -0.718 and -1.855, respectively. After matching, the coefficients changed to -0.394, -0.824 and -1.278. Nurses from iii-A hospitals had higher knowledge and attitude scores than nurses from ii-A hospitals, but no significant practice scores difference was observed between various rankings of hospitals. CONCLUSIONS: The KAP of nurses on nursing post-stroke dysphagia patients were different in iii-A and ii-A hospitals. Administrators should strengthen management, provide more learning resources and trainings to meet nurses' needs about methods to deal with and recognize dysphagia, so as to further improve the quality of post-stroke dysphagia management.

2.
Cancer Cell Int ; 19: 288, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31754346

RESUMEN

BACKGROUND: The study aimed to explore the associations between the interactions of serum vitamin B2 or B12 levels, aberrant DNA methylation of p16 or p53 and MTHFR C677T polymorphism and the risks of esophageal squamous cell carcinoma (ESCC) and esophageal precancerous lesion (EPL). METHODS: 200 ESCC cases, 200 EPL cases and 200 normal controls were matched by age (± 2 years) and gender. Serum vitamin B2 and B12 levels, MTHFR C677T genetic polymorphisms and the methylation status of genes were assessed. Chi square test, one-way analysis of variance and binary logistic regression were performed. RESULTS: The lowest quartile of both serum vitamin B2 and B12 with TT genotype showed significant increased EPL risk (OR = 4.91, 95% CI 1.31-18.35; OR = 6.88, 95% CI 1.10-42.80). The highest quartile of both serum vitamin B2 and B12 with CC genotype showed significant decreased ESCC risk (OR = 0.16, 95% CI 0.04-0.60; OR = 0.10, 95% CI 0.02-0.46). The ORs of p16 methylation for genotype CT and TT were 1.98 (95% CI 1.01-3.89) and 17.79 (95% CI 2.26-140.22) in EPL, 4.86 (95% CI 2.48-9.50) and 20.40 (95% CI 2.53-164.81) in ESCC, respectively. Similarly, p53 methylation with genotype TT was associated with increased EPL and ESCC risks (OR = 13.28, 95% CI 1.67-105.70; OR = 15.24, 95% CI 1.90-122.62). CONCLUSIONS: The MTHFR C677T genotype and serum vitamin B2 or B12 levels may interact in ways which associated with the EPL and ESCC risks. The gene-gene interaction suggested that aberrant DNA methyaltion of either p16 or p53 combined with T alleles of MTHFR was associated with increased risks of both EPL and ESCC.

3.
Wei Sheng Yan Jiu ; 43(2): 254-8, 2014 Mar.
Artículo en Zh | MEDLINE | ID: mdl-24868979

RESUMEN

OBJECTIVE: To study the association between methylene tetrahydrofolate reductase (MTHFR) C677T polymorphism and esophageal cancer risk. METHODS: esophageal cancer cases, 150 esophageal precancerous lesions cases and 207 healthy controls were selected in a high esophageal cancer incidence region in Huai'an, China. MTHFR genotypes at the C677T site were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods. Chi-square test was used to estimate MTHFR genotype frequency distribution in the control, esophageal precancerous lesions (mild, moderate and severe) and esophageal cancer groups. RESULTS: MTHFR C677T genotype distributions in the control and esophageal cancer groups had no significant differences. There was a significant difference in the frequency distribution of MTHFR 677TT genotype and T allele between the esophageal precancerous lesions group and the control group (P < 0.05). Compared with the mild group, the MTHFR 677TT genotype distribution in the moderate or severe esophageal precancerous lesions groups and T allele in the moderate group had significant differences (P < 0.05). CONCLUSION: There may be no correlation between the MTHFR C677T gene polymorphism and susceptibility to esophageal cancer, but it had correlation with susceptibility to esophageal precancerous lesions. Individuals with MTHFR 677TT variant genotypes and T allele were at higher risk of esophageal precancerous lesions.


Asunto(s)
Neoplasias Esofágicas/genética , Predisposición Genética a la Enfermedad , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Alelos , China , Genotipo , Humanos , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Polimorfismo de Longitud del Fragmento de Restricción , Riesgo
4.
World J Gastroenterol ; 30(23): 3005-3015, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38946876

RESUMEN

BACKGROUND: Gastric cancer (GC) is the most common malignant tumor and ranks third for cancer-related deaths among the worldwide. The disease poses a serious public health problem in China, ranking fifth for incidence and third for mortality. Knowledge of the invasive depth of the tumor is vital to treatment decisions. AIM: To evaluate the diagnostic performance of double contrast-enhanced ultrasonography (DCEUS) for preoperative T staging in patients with GC by comparing with multi-detector computed tomography (MDCT). METHODS: This single prospective study enrolled patients with GC confirmed by preoperative gastroscopy from July 2021 to March 2023. Patients underwent DCEUS, including ultrasonography (US) and intravenous contrast-enhanced ultrasonography (CEUS), and MDCT examinations for the assessment of preoperative T staging. Features of GC were identified on DCEUS and criteria developed to evaluate T staging according to the 8th edition of AJCC cancer staging manual. The diagnostic performance of DCEUS was evaluated by comparing it with that of MDCT and surgical-pathological findings were considered as the gold standard. RESULTS: A total of 229 patients with GC (80 T1, 33 T2, 59 T3 and 57 T4) were included. Overall accuracies were 86.9% for DCEUS and 61.1% for MDCT (P < 0.001). DCEUS was superior to MDCT for T1 (92.5% vs 70.0%, P < 0.001), T2 (72.7% vs 51.5%, P = 0.041), T3 (86.4% vs 45.8%, P < 0.001) and T4 (87.7% vs 70.2%, P = 0.022) staging of GC. CONCLUSION: DCEUS improved the diagnostic accuracy of preoperative T staging in patients with GC compared with MDCT, and constitutes a promising imaging modality for preoperative evaluation of GC to aid individualized treatment decision-making.


Asunto(s)
Medios de Contraste , Tomografía Computarizada Multidetector , Estadificación de Neoplasias , Neoplasias Gástricas , Ultrasonografía , Humanos , Neoplasias Gástricas/diagnóstico por imagen , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía , Persona de Mediana Edad , Masculino , Femenino , Medios de Contraste/administración & dosificación , Estudios Prospectivos , Anciano , Ultrasonografía/métodos , Ultrasonografía/estadística & datos numéricos , Tomografía Computarizada Multidetector/métodos , Adulto , China/epidemiología , Gastroscopía/métodos , Estómago/diagnóstico por imagen , Estómago/patología , Estómago/cirugía , Anciano de 80 o más Años
5.
Wei Sheng Yan Jiu ; 42(3): 451-4, 2013 May.
Artículo en Zh | MEDLINE | ID: mdl-23805525

RESUMEN

OBJECTIVE: To study the relationship between serum folic acid and VB2 levels and esophageal cancer. METHOD: The enzyme-linked immunosorbent assay was used to observe the serum folic acid and vitamin B2 levels of the 1:1:1 paired of 106 groups, which include 106 cases of esophageal cancer, 106 cases of esophageal precancerous lesions and 106 cases of normal control group. RESULTS: The levels of folic acid and VB2 in serum of esophageal cancer group and esophageal precancerous lesions group were significantly lower than normal control group (P<0.05), the level of folic acid in serum of esophageal cancer group was significantly lower than esophageal precancerous lesions group (P<0.05), but the difference of the serum VB2 of esophageal cancer group and esophageal precancerous lesions group was not statistically significant (P>0.05). CONCLUSION: The folic acid and vitamin B2 deficiency has the relationship with the esophageal cancer occurrence and development.


Asunto(s)
Neoplasias Esofágicas/sangre , Ácido Fólico/sangre , Lesiones Precancerosas/sangre , Riboflavina/sangre , Anciano , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Neoplasias Esofágicas/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Lesiones Precancerosas/epidemiología
6.
Anal Methods ; 13(41): 4934-4940, 2021 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-34612218

RESUMEN

An electrochemical aptasensor with high sensitivity, specificity, and good intra-day reproducibility is reported to meet the detection needs of vascular endothelial growth factor (VEGF). The toehold-mediated strand displacement recycling amplification and VEGF aptamer are integrated in the biosensor. The probe A is hybridized with the VEGF aptamer to form the probe A-aptamer complex. When VEGF is introduced, the aptamer specifically binds with VEGF, and probe A can be liberated. Then, the free probe A captures the toehold region of the Hp1, leading the exposure of the toehold region on the other end of Hp1. Similarly, Hp2 and Hp3 are also immobilized on the surface of the electrode; thus, the methylene blue labelled on Hp2 and Hp3 causes the current response. With the signal transduction mechanism, the expression level of VEGF can be detected quantitatively. With a series of optimizations of sensor parameters, high sensitivity and specificity of the VEGF detection sensor can be achieved with a detection limit as low as 10 pg mL-1. This significant performance has good intra-day reproducibility, and it can be applied to human biological samples such as serum, urine, and saliva to detect the VEGF content.


Asunto(s)
Aptámeros de Nucleótidos , Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/metabolismo , Técnicas Electroquímicas , Humanos , Límite de Detección , Reproducibilidad de los Resultados , Factor A de Crecimiento Endotelial Vascular/química
7.
Genes Nutr ; 15(1): 18, 2020 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-32993492

RESUMEN

BACKGROUND: This study evaluated gene-nutrition interactions between folate and the aberrant DNA methylation of tumor suppressor genes in different stages of carcinogenesis of esophageal squamous cell carcinoma (ESCC). METHODS: Two hundred ESCC cases, 200 esophageal precancerous lesion (EPL) cases, and 200 controls matched by age (± 2 years) and gender were used for this study. Baseline data and dietary intake information was collected via questionnaire. The serum folate levels and methylation status of promoter regions of p16 and p53 were detected. RESULTS: The interactions of increased serum folate level with unmethylated p16 and p53 promoter regions were significantly associated with a reduced risk of both EPL and ESCC (p for interaction < 0.05). The interactions of the lowest quartile of serum folate level with p16 or p53 methylation was significantly associated with an increased risk of ESCC (OR = 2.96, 95% CI, 1.45-6.05; OR = 2.34, 95% CI, 1.15-4.75). An increased serum folate level was also related to a decreasing trend of EPL and ESCC risks when p16 or p53 methylation occurred. The interaction of spinach, Chinese cabbage, liver and bean intake with unmethylated p16 and p53 was significantly associated with a reduced risk of EPL or ESCC (p for interaction < 0.05). CONCLUSIONS: The interactions between a high folate level and unmethylated p16 and p53 promoter regions may have a strong preventive effect on esophageal carcinogenesis. Additionally, a high folate level may offset the tumor-promoting effects of aberrant DNA methylation of the genes, but it is also noteworthy that a very high level of folate may not have a protective effect on EPL in some cases.

8.
Exp Ther Med ; 16(3): 2119-2125, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30186448

RESUMEN

Knee osteoarthritis is the most common degenerative disease of the joints caused by articular cartilage injury, degradation of the joint edge and subchondral bone hyperplasia. Various treatments are used to alleviate the symptoms of patients with knee osteoarthritis, including analgesics and intra-articular injections. Platelet-rich plasma (PRP) is an autologous and multifunctional platelet concentrate of the blood, which stimulates the cartilage healing process and improves the damage caused by articular disease. Hyaluronic acid (HA) is an effective treatment for patients with knee osteoarthritis. In the current study, the effectiveness of PRP and HA combination therapy administered via intra-articular injections for patients with knee osteoarthritis was analyzed. A total of 360 patients with knee osteoarthritis were randomized into four different treatment groups as follows: Double-blind treatment with PRP (2-14 ml); double-blind treatment with HA (0.1-0.3 mg); combination therapy of PRP and HA; and placebo groups. Following treatment, all patients were evaluated using the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and Common Toxicity Criteria. The most common treatment-emergent adverse events were hypertension and proteinuria. The current study demonstrated that PRP and HA treatment significantly improved arthralgia, and PRP treatment was determined to be significantly more effective than HA treatment using the WOMAC pain score (P<0.05). PRP and HA combination treatment significantly improved arthralgia, reduced humoral and cellular immune responses and promoted angiogenesis, which improved the patients' histological parameters compared with PRP or HA treatment alone. These results suggested that PRP and HA combination treatment may be a potential treatment option for patients with knee osteoarthritis in the future.

9.
Nutr Res ; 43: 82-88, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28673468

RESUMEN

Abdominal obesity is associated with an increased risk of insulin resistance, which may be a potential contributor to dyslipidemia. However, the relationship between postprandial insulin resistance and lipid metabolism in abdominally obese subjects remains unknown. We hypothesized that postprandial dyslipidemia would be exaggerated in abdominally obese subjects with high postprandial insulin resistance. To test this hypothesis, serum glucose, insulin, triglycerides, total cholesterol, high-density lipoprotein cholesterol, and apolipoprotein B were measured at baseline and postprandial state at 0.5, 1, 2, 4, 6, and 8 hours after a liquid high-fat meal in non-abdominally obese controls (n=44) and abdominally obese subjects with low (AO-LPIR, n=40), middle (n=40), and high postprandial insulin resistance (AO-HPIR, n=40) based on the tertiles ratio of the insulin to glucose areas under the curve (AUC). Their serum adipokines were tested at baseline only. Fasting serum leptin was higher (P<.05) in AO-HPIR than that in AO-LPIR and controls. Postprandial triglycerides AUC was higher (P<.05), whereas high-density lipoprotein cholesterol AUC was lower (P<.05), in AO-HPIR than those in AO-LPIR and controls. Postprandial AUCs for total cholesterol and apolipoprotein B were similar in abdominally obese subjects with different degrees of postprandial insulin resistance and controls. The present study indicated that the higher degree of postprandial insulin resistance, the more adverse lipid profiles in abdominally obese subjects, which provides insight into opportunity for screening in health.


Asunto(s)
HDL-Colesterol/sangre , Dieta Alta en Grasa , Resistencia a la Insulina , Obesidad Abdominal/sangre , Periodo Posprandial , Triglicéridos/sangre , Adulto , Apolipoproteínas B/sangre , Glucemia/metabolismo , LDL-Colesterol/sangre , Dislipidemias/sangre , Femenino , Humanos , Insulina/sangre , Leptina/sangre , Metabolismo de los Lípidos , Masculino , Comidas , Persona de Mediana Edad , Tamaño de la Muestra
10.
Med Chem ; 11(4): 383-90, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25381995

RESUMEN

Lycium barbarum polysaccharide (LBP) has traditionally been used in Chinese medicine as a chief ingredient of Lycium barbarum (wolf berry/goji berry) for the treatment of various diseases with the symptoms of frequent drinking and urination. This study was conducted as a randomized, controlled clinical trial. A total of 67 patients with type 2 diabetes (30 in control group and 37 in LBP group) were enrolled in this prospective, randomized, double-blind study (administration at 300 mg/day body weight). In order to observe the hypoglycemic and lipid-lowering activity of LBP in patients with type 2 diabetes after dinner, various tests were conducted between control and LBP intervention groups in 3 months. Although, the study had small sample size and short follow-up, significant findings were observed. The results of our study indicated a remarkable protective effect of LBP in patients with type 2 diabetes. Serum glucose was found to be significantly decreased and insulinogenic index increased during OMTT after 3 months administration of LBP. LBP also increased HDL levels in patients with type 2 diabetes. It showed more obvious hypoglycemic efficacy for those people who did not take any hypoglycemic medicine compared to patients taking hypoglycemic medicines. This study showed LBP to be a good potential treatment aided-agent for type 2 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Medicamentos Herbarios Chinos/química , Hipoglucemiantes/uso terapéutico , Lycium/química , Anciano , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/fisiopatología , Método Doble Ciego , Esquema de Medicación , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/uso terapéutico , Femenino , Humanos , Hipoglucemiantes/aislamiento & purificación , Insulina/agonistas , Insulina/sangre , Lipoproteínas HDL/agonistas , Lipoproteínas HDL/sangre , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
11.
Asian Pac J Cancer Prev ; 15(2): 819-23, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24568502

RESUMEN

OBJECTIVE: The aim was to evaluate roles of vitamin D3 (VD3) and beta-carotene (BC) in the development of esophageal squamous cell carcinoma (ESCC) in a high-risk area, Huai'an District, Huai'an City, China. METHODS: 100 new ESCC diagnosed cases from 2007 to 2008 and 200 residency- age-, and sex-matched healthy controls were recruited. Data were collected from questionnaires, including a food frequency questionnaire (FFQ) to calculate the BC intake, and reversed phase high-performance liquid chromatography (RP-HPLC) was used to measure the serum concentrations of BC and VD3. Odds ratios (OR) and 95% confidence intervals (CI) were calculated in conditional logistic regression models. RESULTS: The average dietary intake of BC was 3322.9 µg (2032.4- 5734.3) in the case group and 3626.8 µg (1961.9-5827.9) in control group per capita per day with no significant difference by Wilcoxon test (p>0.05). However, the levels of VD3 and BC in the case group were significantly lower than in the control group (p<0.05). The OR values of the highest quartile and the lowest quartile of VD3 and BC in serum samples were both 0.13. CONCLUSION: Our results add to the evidence that high circulating levels of VD3 and BC are associated with a reduced risk of ESCC in this Chinese population.


Asunto(s)
Carcinoma de Células Escamosas/etiología , Colecalciferol/deficiencia , Neoplasias Esofágicas/etiología , beta Caroteno/deficiencia , Carcinoma de Células Escamosas/sangre , Estudios de Casos y Controles , China , Colecalciferol/sangre , Cromatografía Líquida de Alta Presión , Neoplasias Esofágicas/sangre , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , beta Caroteno/sangre
12.
Exp Ther Med ; 7(1): 55-60, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24348764

RESUMEN

Previous epidemiological studies have demonstrated a correlation between fumonisin B1 (FB1) and human esophageal cancer in China, Iran and South Africa. The purpose of this study was to investigate the effects of FB1 on the proliferation, cell-cycle and apoptosis of normal human esophageal epithelial cells (HEECs) and to explore the molecular mechanisms of these effects. The proliferation of HEECs treated with FB1 was assessed using a colorimetric assay, while analyses of the cell cycle and apoptosis were performed using flow cytometry and the measurement of the protein expressions of genes associated with the cell cycle was conducted using western blotting. The results showed that FB1 stimulated the proliferation of HEECs, decreased the percentage of cells in the G0/G1 phase and reduced apoptosis. The western blotting results showed that FB1 significantly increased the protein expression of cyclin D1 and significantly decreased the protein expression of cyclin E, p21 and p27. The results indicated that FB1 stimulated the proliferation of HEECs by affecting the cell cycle and apoptosis. This mechanism was associated with changes in cyclin D1, cyclin E, p21 and p27 expression.

13.
Asian Pac J Cancer Prev ; 13(11): 5455-61, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23317200

RESUMEN

Luteolin is a plant flavonoid which exhibits anti-oxidative, anti-inflammatory and anti-tumor effects. However, the antiproliferative potential of luteolin is not fully understood. In this study, we investigated the effect of luteolin on cell cycling and apoptosis in human esophageal squamous carcinoma cell line Eca109 cells. MTT assays showed that luteolin had obvious cytotoxicity on Eca109 with an IC50 of 70.7±1.72 µM at 24 h. Luteolin arrested cell cycle progression in the G0/G1 phase and prevented entry into S phase in a dose- and time-dependent manner. as assessed by FCM. Luteolin induced apoptosis of Eca109 cells was demonstrated by AO/EB staining assay and annexin V-FITC/PI staining. Moreover, luteolin downregulated the expression of cyclin D1, survivin and c-myc, and it also upregulated the expression of p53, in line with the fact that luteolin was able to inhibit Eca109 cell proliferation.


Asunto(s)
Apoptosis/efectos de los fármacos , Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas/patología , Proliferación Celular/efectos de los fármacos , Neoplasias Esofágicas/patología , Luteolina/farmacología , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/metabolismo , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Ensayo de Inmunoadsorción Enzimática , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
14.
Asian Pac J Cancer Prev ; 13(12): 6327-32, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23464453

RESUMEN

Esophageal cancer is a common malignant tumor occurring in human esophageal epithelial tissue. The primary purpose of this paper was to define the effects of ß-carotene and 1,25-dihydroxyvitamin D3, alone and in combination, on cell proliferation, cell cycle and apoptosis of human esophageal cancer EC9706 cells. Treatment with different concentrations of ß-carotene and/or 1,25-dihydroxyvitamin D3. MTT assay showed that ß-carotene and 1,25-dihydroxyvitamin D3 significantly inhibited proliferation of EC9706 cells in a dose- and time-dependent manner. Further studies also demonstrated that ß-carotene alone or 1,25-dihydroxyvitamin D3 alone caused a marked increase on the induction of apoptosis in EC9706 cells. The percentage of G0/G1-phase cells significantly increased on addition of 1,25-dihydroxyvitamin D3 alone, but there were no significant changes with ß-carotene alone. These two agents in combination synergistically inhibited cell growth and induced apoptosis. Therefore, our results indicate that ß-carotene and 1,25-dihydroxyvitamin D3 in combination may provide a novel strategy for preventing and treating esophageal cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Neoplasias Esofágicas/tratamiento farmacológico , Calcitriol/administración & dosificación , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Humanos , beta Caroteno/administración & dosificación
15.
Appl Opt ; 45(20): 4810-4, 2006 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-16807585

RESUMEN

We designed and demonstrated what we believe to be a novel sensor for simultaneous measurement of stress and temperature. A fiber Bragg grating is flatly adhered to the surface of a loop thin-wall section beam. The theoretical analyses and the experimental results show that both the central wavelength shift and the chirped bandwidth of the grating reflection spectrum have a linear relationship with the stress and the temperature, respectively, and the slopes of them are different. Therefore, the temperature and stress can be discriminated by interrogating the chirped fiber grating. Moreover, we also investigated the strain of the loop thin-wall section beam, and the results show that the strain is cosine proportional to the double positional angle.

16.
Opt Lett ; 31(15): 2269-71, 2006 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-16832455

RESUMEN

Temperature-insensitive dynamic pressure measurement using a single fiber Bragg grating (FBG) based on reflection spectrum bandwidth modulation and optical power detection is proposed. A specifically designed double-hole cantilever beam is used to provide a pressure-induced axial strain gradient along the sensing FBG and is also used to modulate the reflection bandwidth of the grating. The bandwidth modulation is immune to spatially uniform temperature effects, and the pressure can be unambiguously determined by measuring the reflected optical power, avoiding the complex wavelength interrogation system. The system acquisition time is up to 85 Hz for dynamic pressure measurement, and the thermal fluctuation is kept less than 1.2% full-scale for a temperature range of -10 degrees C to 80 degrees C.

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