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A Prospective Study of Bevacizumab and Neoadjuvant Concurrent Chemoradiation in Locally Advanced Esophageal Squamous Cell Carcinoma: Paradoxical Increase in Circulating Vascular Endothelial Growth Factor-A and Effect on Outcome. Int J Radiat Oncol Biol Phys 2023; 117:e302-e303. [PMID: 37785104 DOI: 10.1016/j.ijrobp.2023.06.2320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) In the prior prospective biomarker study, high serum vascular endothelial growth factor-A (VEGF-A) was associated with a poor prognosis. We conducted a prospective phase II trial of adding Bevacizumab, an anti-VEGF-A monoclonal antibody, to neoadjuvant concurrent chemoradiation (neoCCRT) for patients with locally advanced esophageal squamous cell carcinoma (LA-ESCC). This prospective biomarker study aims to evaluate the expressions of angiogenesis-associated circulating biomarkers before and after neoCCRT and compare clinical outcomes for patients receiving platinum/5-fluorouracil (PF) with or without Bevacizumab. MATERIALS/METHODS Patients with biopsy-proven resectable non-T4 LA-ESCC were enrolled for the prospective phase II trial investigating PF-neoCCRT plus Bevacizumab (BPF group). A parallel patient cohort enrolled in a prospective biomarker study receiving PF-neoCCRT was included in the present analysis as the control group (PF group). Radiotherapy was delivered with 40 Gy in 20 fractions. All patients had restaging workups after enoCCRT and underwent radical esophagectomy if the disease remained resectable. Serums were collected before and after neoCCRT. The serum concentrations of angiogenesis-associated biomarkers were determined by the multiplex enzyme-linked immunosorbent assay. Survival analyses were performed by the Kaplan-Meier method. The t-test and log-rank test were used to compare differences in biomarker expression and survival between groups. RESULTS From 2016 to 2019, 43 patients (BPF/PF group: 21/22) were enrolled in the study. Twenty patients in each group had serum samples available for biomarker analysis. 15 out of 21 patients in the BPF group and 20 out of 22 patients in the PF group underwent radical esophagectomy. Six patients in the BPF group and nine patients in the PF group achieved pathological complete responses. The median overall survival for the BPF and PF group was 20.8 months and not-reached, respectively (hazard ratio = 1.33, long rank p = 0.58). In the BPF group, the serum VEGF-A level was significantly increased from an average value of 446 pg/mL to 723 pg/mL after neoCCRT (p = 0.037), while its level was decreased from 815 ng/mL to 380 pg/mL in the PF group (p = 0.104). In addition, the expression value of circulating Angiopoietin-1 was not changed in the BPF group (before neoCCRT, mean value = 828 pg/mL; after neoCCRT, mean value 762 pg/mL, p = 0.67). In contrast, serum Angiopoietin-1 level was reduced from an average value of 659 pg/mL before neoCCRT to 271 pg/mL after neoCCRT (p = 0.002) in the PF group. CONCLUSION The addition of Bevacizumab to PF-neoCCRT did not improve pathological or survival outcomes in patients with resectable LA-ESCC. Adding a single dose of Bevacizumab paradoxically increases circulating VEGF-A while maintaining the Angiopoietin-1 serum level after neoCCRT. Further investigation by using additional VEGF-A inhibition may be required to achieve sustained angiogenesis blocked for tumor control.
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Internal moisture barrier layer for improving high-humidity reliability of miniature light emitting diode die without encapsulation. OPTICS EXPRESS 2023; 31:33732-33740. [PMID: 37859146 DOI: 10.1364/oe.499380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 09/06/2023] [Indexed: 10/21/2023]
Abstract
Atomic layer deposited Al2O3 films are incorporated into miniature light emitting diodes (mini-LEDs) as an internal moisture barrier layer. The experimental results show that the water vapor transmission rate reaches ≤10-4 g/m2/day when the Al2O3 thickness is ≥40 nm. The mini-LED with a 40 nm-thick Al2O3 layer shows negligible degradation after 1000 h of 85°C/85% relative humidity testing, whereas the device without an Al2O3 layer fails after only 500 h due to delamination occurring at the GaN surface. Current-voltage characteristics of the device without an Al2O3 moisture barrier layer indicate an increase in series resistance and ideality factor. This study provides a simple, light-weighting method to have a satisfactory encapsulation function for miniature LEDs.
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Growth of GaN Thin Films Using Plasma Enhanced Atomic Layer Deposition: Effect of Ammonia-Containing Plasma Power on Residual Oxygen Capture. Int J Mol Sci 2022; 23:ijms232416204. [PMID: 36555844 PMCID: PMC9782612 DOI: 10.3390/ijms232416204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 12/13/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022] Open
Abstract
In recent years, the application of (In, Al, Ga)N materials in photovoltaic devices has attracted much attention. Like InGaN, it is a direct band gap material with high absorption at the band edge, suitable for high efficiency photovoltaic devices. Nonetheless, it is important to deposit high-quality GaN material as a foundation. Plasma-enhanced atomic layer deposition (PEALD) combines the advantages of the ALD process with the use of plasma and is often used to deposit thin films with different needs. However, residual oxygen during growth has always been an unavoidable issue affecting the quality of the resulting film, especially in growing gallium nitride (GaN) films. In this study, the NH3-containing plasma was used to capture the oxygen absorbed on the growing surface to improve the quality of GaN films. By diagnosing the plasma, NH2, NH, and H radicals controlled by the plasma power has a strong influence not only on the oxygen content in growing GaN films but also on the growth rate, crystallinity, and surface roughness. The NH and NH2 radicals contribute to the growth of GaN films while the H radicals selectively dissociate Ga-OH bonds on the film surface and etch the grown films. At high plasma power, the GaN film with the lowest Ga-O bond ratio has a saturated growth rate, a better crystallinity, a rougher surface, and a lower bandgap. In addition, the deposition mechanism of GaN thin films prepared with a trimethylgallium metal source and NH3/Ar plasma PEALD involving oxygen participation or not is also discussed in the study.
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Deposition Mechanism and Characterization of Plasma-Enhanced Atomic Layer-Deposited SnO x Films at Different Substrate Temperatures. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:2859. [PMID: 36014724 PMCID: PMC9416374 DOI: 10.3390/nano12162859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 08/15/2022] [Accepted: 08/15/2022] [Indexed: 06/15/2023]
Abstract
The promising functional tin oxide (SnOx) has attracted tremendous attention due to its transparent and conductive properties. The stoichiometric composition of SnOx can be described as common n-type SnO2 and p-type Sn3O4. In this study, the functional SnOx films were prepared successfully by plasma-enhanced atomic layer deposition (PEALD) at different substrate temperatures from 100 to 400 °C. The experimental results involving optical, structural, chemical, and electrical properties and morphologies are discussed. The SnO2 and oxygen-deficient Sn3O4 phases coexisting in PEALD SnOx films were found. The PEALD SnOx films are composed of intrinsic oxygen vacancies with O-Sn4+ bonds and then transformed into a crystalline SnO2 phase with increased substrate temperature, revealing a direct 3.5−4.0 eV band gap and 1.9−2.1 refractive index. Lower (<150 °C) and higher (>300 °C) substrate temperatures can cause precursor condensation and desorption, respectively, resulting in reduced film qualities. The proper composition ratio of O to Sn in PEALD SnOx films near an estimated 1.74 suggests the highest mobility of 12.89 cm2 V−1 s−1 at 300 °C.
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Compact Ga2O3 Thin Films Deposited by Plasma Enhanced Atomic Layer Deposition at Low Temperature. NANOMATERIALS 2022; 12:nano12091510. [PMID: 35564219 PMCID: PMC9100640 DOI: 10.3390/nano12091510] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 04/18/2022] [Accepted: 04/27/2022] [Indexed: 12/07/2022]
Abstract
Amorphous Gallium oxide (Ga2O3) thin films were grown by plasma-enhanced atomic layer deposition using O2 plasma as reactant and trimethylgallium as a gallium source. The growth rate of the Ga2O3 films was about 0.6 Å/cycle and was acquired at a temperature ranging from 80 to 250 °C. The investigation of transmittance and the adsorption edge of Ga2O3 films prepared on sapphire substrates showed that the band gap energy gradually decreases from 5.04 to 4.76 eV with the increasing temperature. X-ray photoelectron spectroscopy (XPS) analysis indicated that all the Ga2O3 thin films showed a good stoichiometric ratio, and the atomic ratio of Ga/O was close to 0.7. According to XPS analysis, the proportion of Ga3+ and lattice oxygen increases with the increase in temperature resulting in denser films. By analyzing the film density from X-ray reflectivity and by a refractive index curve, it was found that the higher temperature, the denser the film. Atomic force microscopic analysis showed that the surface roughness values increased from 0.091 to 0.187 nm with the increasing substrate temperature. X-ray diffraction and transmission electron microscopy investigation showed that Ga2O3 films grown at temperatures from 80 to 200 °C were amorphous, and the Ga2O3 film grown at 250 °C was slightly crystalline with some nanocrystalline structures.
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Deposition and Characterization of RP-ALD SiO 2 Thin Films with Different Oxygen Plasma Powers. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:1173. [PMID: 33947065 PMCID: PMC8145387 DOI: 10.3390/nano11051173] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 04/23/2021] [Accepted: 04/26/2021] [Indexed: 02/06/2023]
Abstract
In this study, silicon oxide (SiO2) films were deposited by remote plasma atomic layer deposition with Bis(diethylamino)silane (BDEAS) and an oxygen/argon mixture as the precursors. Oxygen plasma powers play a key role in the quality of SiO2 films. Post-annealing was performed in the air at different temperatures for 1 h. The effects of oxygen plasma powers from 1000 W to 3000 W on the properties of the SiO2 thin films were investigated. The experimental results demonstrated that the SiO2 thin film growth per cycle was greatly affected by the O2 plasma power. Atomic force microscope (AFM) and conductive AFM tests show that the surface of the SiO2 thin films, with different O2 plasma powers, is relatively smooth and the films all present favorable insulation properties. The water contact angle (WCA) of the SiO2 thin film deposited at the power of 1500 W is higher than that of other WCAs of SiO2 films deposited at other plasma powers, indicating that it is less hydrophilic. This phenomenon is more likely to be associated with a smaller bonding energy, which is consistent with the result obtained by Fourier transformation infrared spectroscopy. In addition, the influence of post-annealing temperature on the quality of the SiO2 thin films was also investigated. As the annealing temperature increases, the SiO2 thin film becomes denser, leading to a higher refractive index and a lower etch rate.
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Properties and Mechanism of PEALD-In 2O 3 Thin Films Prepared by Different Precursor Reaction Energy. NANOMATERIALS 2021; 11:nano11040978. [PMID: 33920231 PMCID: PMC8070178 DOI: 10.3390/nano11040978] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/02/2021] [Accepted: 04/07/2021] [Indexed: 11/16/2022]
Abstract
Indium oxide (In2O3) film has excellent optical and electrical properties, which makes it useful for a multitude of applications. The preparation of In2O3 film via atomic layer deposition (ALD) method remains an issue as most of the available In-precursors are inactive and thermally unstable. In this work, In2O3 film was prepared by ALD using a remote O2 plasma as oxidant, which provides highly reactive oxygen radicals, and hence significantly enhancing the film growth. The substrate temperature that determines the adsorption state on the substrate and reaction energy of the precursor was investigated. At low substrate temperature (100–150 °C), the ratio of chemically adsorbed precursors is low, leading to a low growth rate and amorphous structure of the films. An amorphous-to-crystalline transition was observed at 150–200 °C. An ALD window with self-limiting reaction and a reasonable film growth rate was observed in the intermediate temperature range of 225–275 °C. At high substrate temperature (300–350 °C), the film growth rate further increases due to the decomposition of the precursors. The resulting film exhibits a rough surface which consists of coarse grains and obvious grain boundaries. The growth mode and properties of the In2O3 films prepared by plasma-enhanced ALD can be efficiently tuned by varying the substrate temperature.
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Chemical Reaction and Ion Bombardment Effects of Plasma Radicals on Optoelectrical Properties of SnO 2 Thin Films via Atomic Layer Deposition. MATERIALS 2021; 14:ma14030690. [PMID: 33540775 PMCID: PMC7867222 DOI: 10.3390/ma14030690] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 01/11/2021] [Accepted: 01/26/2021] [Indexed: 12/24/2022]
Abstract
In this study, the effect of radical intensity on the deposition mechanism, optical, and electrical properties of tin oxide (SnO2) thin films is investigated. The SnO2 thin films are prepared by plasma-enhanced atomic layer deposition with different plasma power from 1000 to 3000 W. The experimental results show that plasma contains different amount of argon radicals (Ar*) and oxygen radicals (O*) with the increased power. The three deposition mechanisms are indicated by the variation of Ar* and O* intensities evidenced by optical emission spectroscopy. The adequate intensities of Ar* and O* are obtained by the power of 1500 W, inducing the highest oxygen vacancies (OV) ratio, the narrowest band gap, and the densest film structure. The refractive index and optical loss increase with the plasma power, possibly owing to the increased film density. According to the Hall effect measurement results, the improved plasma power from 1000 to 1500 W enhances the carrier concentration due to the enlargement of OV ratio, while the plasma powers higher than 1500 W further cause the removal of OV and the significant bombardment from Ar*, leading to the increase of resistivity.
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Protocol for a feasibility and early efficacy study of the Comprehensive Lifestyle Improvement Program for Prostate Cancer-2 (CLIPP2). Contemp Clin Trials Commun 2021; 21:100701. [PMID: 33511299 PMCID: PMC7815988 DOI: 10.1016/j.conctc.2021.100701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 09/18/2020] [Accepted: 01/01/2021] [Indexed: 11/16/2022] Open
Abstract
Background Although androgen deprivation therapy (ADT) for prostate cancer demonstrates improved overall and disease-free survival, it is associated with adverse effects such as obesity and metabolic syndrome that increase risk of cardiometabolic disease and diabetes type 2. ADT also leads to fatigue, depression and erectile dysfunction, which reduce quality of life (QoL). Lifestyle modification has shown promise in reducing obesity, metabolic syndrome and diabetes type 2 in other disease types. However, there is a paucity of data regarding the utility of lifestyle modification in men receiving ADT for prostate cancer. Methods The primary aim of the Comprehensive Lifestyle Improvement Program for Prostate Cancer-2 (CLIPP2) is to test the feasibility of conducting a 24-week lifestyle modification intervention in men on ADT for prostate cancer. Additionally, it will also determine the effect of this intervention on weight loss, cardiometabolic markers (secondary aim and markers of interest: serum glucose, insulin resistance, hemoglobin A1C and lipid panel), and QoL (tertiary aim). The intervention will be delivered weekly via telephone for the first 10 weeks and bi-weekly for the remaining 14 weeks. Questionnaires and serum samples will be collected at baseline, week 12, and week 24. Anthropometric measurements will be collected at baseline, week 6, week 12, week 18 and week 24. Results We hypothesize that the CLIPP2 intervention will produce a 7% weight loss that will result in improved markers associated with cardiometabolic disease and type 2 diabetes in the study population. Conclusion Results will provide insight into the role of lifestyle modification in addressing ADT adverse effects as well as provide preliminary data to inform the development of future lifestyle interventions in this area. Trial registration NCT04228055 Clinicaltrials. gov.
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Effect of Annealing Temperature on Spatial Atomic Layer Deposited Titanium Oxide and Its Application in Perovskite Solar Cells. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:E1322. [PMID: 32635629 PMCID: PMC7408533 DOI: 10.3390/nano10071322] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/02/2020] [Accepted: 07/03/2020] [Indexed: 11/16/2022]
Abstract
In this study, spatial atomic layer deposition (sALD) is employed to prepare titanium dioxide (TiO2) thin films by using titanium tetraisopropoxide and water as metal and water precursors, respectively. The post-annealing temperature is varied to investigate its effect on the properties of the TiO2 films. The experimental results show that the sALD TiO2 has a similar deposition rate per cycle to other ALD processes using oxygen plasma or ozone oxidant, implying that the growth is limited by titanium tetraisopropoxide steric hindrance. The structure of the as-deposited sALD TiO2 films is amorphous and changes to polycrystalline anatase at the annealing temperature of 450 °C. All the sALD TiO2 films have a low absorption coefficient at the level of 10-3 cm-1 at wavelengths greater than 500 nm. The annealing temperatures of 550 °C are expected to have a high compactness, evaluated by the refractive index and x-ray photoelectron spectrometer measurements. Finally, the 550 °C-annealed sALD TiO2 film with a thickness of ~8 nm is applied to perovskite solar cells as a compact electron transport layer. The significantly enhanced open-circuit voltage and conversion efficiency demonstrate the great potential of the sALD TiO2 compact layer in perovskite solar cell applications.
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Low Reflection and Low Surface Recombination Rate Nano-Needle Texture Formed by Two-Step Etching for Solar Cells. NANOMATERIALS 2019; 9:nano9101392. [PMID: 31569509 PMCID: PMC6835772 DOI: 10.3390/nano9101392] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Revised: 09/17/2019] [Accepted: 09/25/2019] [Indexed: 11/23/2022]
Abstract
In this study, needle-like and pyramidal hybrid black silicon structures were prepared by performing metal-assisted chemical etching (MACE) on alkaline-etched silicon wafers. Effects of the MACE time on properties of the black silicon wafers were investigated. The experimental results showed that a minimal reflectance of 4.6% can be achieved at the MACE time of 9 min. The height of the nanostructures is below 500 nm, unlike the height of micrometers needed to reach the same level of reflectance for the black silicon on planar wafers. A stacked layer of silicon nitride (SiNx) grown by inductively-coupled plasma chemical vapor deposition (ICPCVD) and aluminum oxide (Al2O3) by spatial atomic layer deposition was deposited on the black silicon wafers for passivation and antireflection. The 3 min MACE etched black silicon wafer with a nanostructure height of less than 300 nm passivated by the SiNx/Al2O3 layer showed a low surface recombination rate of 43.6 cm/s. Further optimizing the thickness of ICPCVD-SiNx layer led to a reflectance of 1.4%. The hybrid black silicon with a small nanostructure size, low reflectance, and low surface recombination rate demonstrates great potential for applications in optoelectronic devices.
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Deposition of Silicon-Based Stacked Layers for Flexible Encapsulation of Organic Light Emitting Diodes. NANOMATERIALS 2019; 9:nano9071053. [PMID: 31340501 PMCID: PMC6669626 DOI: 10.3390/nano9071053] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 07/19/2019] [Accepted: 07/20/2019] [Indexed: 11/20/2022]
Abstract
In this study, inorganic silicon oxide (SiOx)/organic silicon (SiCxHy) stacked layers were deposited by a radio frequency inductively coupled plasma chemical vapor deposition system as a gas diffusion barrier for organic light-emitting diodes (OLEDs). The effects of thicknesses of SiOx and SiCxHy layers on the water vapor transmission rate (WVTR) and residual stress were investigated to evaluate the encapsulation capability. The experimental results showed that the lowest WVTR and residual stress were obtained when the thicknesses of SiOx and SiCxHy were 300 and 30 nm, respectively. Finally, different numbers of stacked pairs of SiOx/SiCxHy were applied to OLED encapsulation. The OLED encapsulated with the six-pair SiOx/SiCxHy exhibited a low turn-on voltage and low series resistance, and device lifetime increased from 7 h to more than 2000 h.
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Enhanced Si Passivation and PERC Solar Cell Efficiency by Atomic Layer Deposited Aluminum Oxide with Two-step Post Annealing. NANOSCALE RESEARCH LETTERS 2019; 14:139. [PMID: 31001714 PMCID: PMC6473015 DOI: 10.1186/s11671-019-2969-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 04/01/2019] [Indexed: 06/09/2023]
Abstract
In this study, aluminum oxide (Al2O3) films were prepared by a spatial atomic layer deposition using deionized water and trimethylaluminum, followed by oxygen (O2), forming gas (FG), or two-step annealing. Minority carrier lifetime of the samples was measured by Sinton WCT-120. Field-effect passivation and chemical passivation were evaluated by fixed oxide charge (Qf) and interface defect density (Dit), respectively, using capacitance-voltage measurement. The results show that O2 annealing gives a high Qf of - 3.9 × 1012 cm-2, whereas FG annealing leads to excellent Si interface hydrogenation with a low Dit of 3.7 × 1011 eV-1 cm-2. Based on the consideration of the best field-effect passivation brought by oxygen annealing and the best chemical passivation brought by forming gas, the two-step annealing process was optimized. It is verified that the Al2O3 film annealed sequentially in oxygen and then in forming gas exhibits a high Qf (2.4 × 1012 cm-2) and a low Dit (3.1 × 1011 eV-1 cm-2), yielding the best minority carrier lifetime of 1097 μs. The SiNx/Al2O3 passivation stack with two-step annealing has a lifetime of 2072 μs, close to the intrinsic lifetime limit. Finally, the passivated emitter and rear cell conversion efficiency was improved from 21.61% by using an industry annealing process to 21.97% by using the two-step annealing process.
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Temperature-Dependent HfO 2/Si Interface Structural Evolution and its Mechanism. NANOSCALE RESEARCH LETTERS 2019; 14:83. [PMID: 30847661 PMCID: PMC6405792 DOI: 10.1186/s11671-019-2915-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Accepted: 02/25/2019] [Indexed: 06/09/2023]
Abstract
In this work, hafnium oxide (HfO2) thin films are deposited on p-type Si substrates by remote plasma atomic layer deposition on p-type Si at 250 °C, followed by a rapid thermal annealing in nitrogen. Effect of post-annealing temperature on the crystallization of HfO2 films and HfO2/Si interfaces is investigated. The crystallization of the HfO2 films and HfO2/Si interface is studied by field emission transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and atomic force microscopy. The experimental results show that during annealing, the oxygen diffuse from HfO2 to Si interface. For annealing temperature below 400 °C, the HfO2 film and interfacial layer are amorphous, and the latter consists of HfO2 and silicon dioxide (SiO2). At annealing temperature of 450-550 °C, the HfO2 film become multiphase polycrystalline, and a crystalline SiO2 is found at the interface. Finally, at annealing temperature beyond 550 °C, the HfO2 film is dominated by single-phase polycrystalline, and the interfacial layer is completely transformed to crystalline SiO2.
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Surface Passivation of Silicon Using HfO 2 Thin Films Deposited by Remote Plasma Atomic Layer Deposition System. NANOSCALE RESEARCH LETTERS 2017; 12:324. [PMID: 28476082 PMCID: PMC5418172 DOI: 10.1186/s11671-017-2098-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 04/20/2017] [Indexed: 06/07/2023]
Abstract
Hafnium oxide (HfO2) thin films have attracted much attention owing to their usefulness in equivalent oxide thickness scaling in microelectronics, which arises from their high dielectric constant and thermodynamic stability with silicon. However, the surface passivation properties of such films, particularly on crystalline silicon (c-Si), have rarely been reported upon. In this study, the HfO2 thin films were deposited on c-Si substrates with and without oxygen plasma pretreatments, using a remote plasma atomic layer deposition system. Post-annealing was performed using a rapid thermal processing system at different temperatures in N2 ambient for 10 min. The effects of oxygen plasma pretreatment and post-annealing on the properties of the HfO2 thin films were investigated. They indicate that the in situ remote plasma pretreatment of Si substrate can result in the formation of better SiO2, resulting in a better chemical passivation. The deposited HfO2 thin films with oxygen plasma pretreatment and post-annealing at 500 °C for 10 min were effective in improving the lifetime of c-Si (original lifetime of 1 μs) to up to 67 μs.
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Perceptions and Practices of Mass Bat Exposure Events in the Setting of Rabies Among U.S. Public Health Agencies. Zoonoses Public Health 2016; 64:127-136. [PMID: 27389926 PMCID: PMC5525325 DOI: 10.1111/zph.12289] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Indexed: 12/25/2022]
Abstract
Current guidelines in the setting of exposures to potentially rabid bats established by the Advisory Committee on Immunization Practices (ACIP) address post-exposure prophylaxis (PEP) administration in situations where a person may not be aware that a bite or direct contact has occurred and the bat is not available for diagnostic testing. These include instances when a bat is discovered in a room where a person awakens from sleep, is a child without an adult witness, has a mental disability or is intoxicated. The current ACIP guidelines, however, do not address PEP in the setting of multiple persons exposed to a bat or a bat colony, otherwise known as mass bat exposure (MBE) events. Due to a dearth of recommendations for response to these events, the reported reactions by public health agencies have varied widely. To address this perceived limitation, a survey of 45 state public health agencies was conducted to characterize prior experiences with MBE and practices to mitigate the public health risks. In general, most states (69% of the respondents) felt current ACIP guidelines were unclear in MBE scenarios. Thirty-three of the 45 states reported prior experience with MBE, receiving an average of 16.9 MBE calls per year and an investment of 106.7 person-hours annually on MBE investigations. PEP criteria, investigation methods and the experts recruited in MBE investigations varied between states. These dissimilarities could reflect differences in experience, scenario and resources. The lack of consistency in state responses to potential mass exposures to a highly fatal disease along with the large contingent of states dissatisfied with current ACIP guidance warrants the development of national guidelines in MBE settings.
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Abstract
A cross-sectional cohort study was conducted to investigate whether ghrelin level in obese women predicts the quality of life (QOL). A total of 307 subjects fulfilled the criteria: (1) age between 20 and 65 years old, (2) body mass index ≥27 kg/m2 (3) waist circumference ≥80 cm were enrolled in the study. All subjects were assigned to one of the plasma ghrelin level categories according to the quartiles. The median of age and BMI of the 307 obese women were 45 ± 18 years and 29.9 ± 4.1 kg/m2, respectively. The main outcome evaluated is the associations of plasma ghrelin level and QOL, which were evaluated using multiple linear regression analysis. Results of linear trend test show significant statistical difference in plasma lipoproteins (triglyceride, cholesterol, HDL-cholestero and LDL-cholesterol = and levels of obesity-related hormone peptides, including leptin, adiponectin, insulin among quartiles of ghrelin. Multiple liner regression analysis of serum obesity-related hormone peptide level and QOL using stepwise method shows ghrelin concentration was the only predictor of QOL, including PCS-12 level (β = -0.18, p = 0.001), MCS-12 level (β = -0.14, p = 0.009), WHOQOL-BREF scores: physical (β = -0.13, p = 0.03), psychological (β = -0.16, p = 0.007), social (β = -0.21, p = < 0.001), and environmental (β = -0.22, p = <0.001), after adjusting other factors for obese female subjects. This study demonstrated that ghrelin concentration is strongly associated with QOL level among obese women. Hence, ghrelin concentration might be a valuable marker to be monitored in obese women.
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Abstract
OBJECTIVES To determine the effect of selenium supplementation on the human proteomic profile. DESIGN Serum samples were collected in this pilot study from a randomized placebo controlled Phase 2 clinical trial (Watchful Waiting (WW)). SETTING Subjects were followed every three months for up to five years at the University of Arizona Prostate Cancer Prevention Program. PARTICIPANTS One hundred and forty men (age < 85 years) had biopsy-proven prostate cancer, a Gleason sum score less than eight, no metastatic cancer, and no prior treatment for prostate cancer. INTERVENTION As part of the WW trial, men were randomized to placebo, selenium 200 μg/day or selenium 800 μg/day. For the purpose of the current study, 40 subjects enrolled in the WW study (20 from the placebo group and 20 from Se 800 μg/day group) were selected. MEASUREMENTS Baseline serum samples were collected at each follow-up visit and stored at -80 degrees Celsius. A multiplexed proteomic panel investigated changes in 120 proteins markers simultaneously. RESULTS Thirteen proteins (Apolipoprotein J, IL-10, IL-1 alpha, MMP-3, IL-12p70, IL-2 receptor alpha, cathepsin B, eotaxin, EGFR, FGF-basic, myeloperoxidase, RANTES, TGF-beta) were determined to be either statistically (p-value < 0.05) or marginally significantly (0.05 < p-value <0.1) changed in the selenium supplemented group as compared to placebo. CONCLUSION Although independent validation of these results is needed, this study is the first of its kind to utilize high throughput fluorescence based protein multiplex panel in analyzing changes in the proteomic profile due to selenium supplementation. Results from this study provide insight into the ability of selenium to modulate numerous protein markers and thus impact various biological processes in humans.
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Does supplementation with green tea extract improve acne in post-adolescent women? A randomized, double-blind, and placebo-controlled clinical trial. Complement Ther Med 2016; 25:159-63. [PMID: 27062963 DOI: 10.1016/j.ctim.2016.03.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Revised: 03/04/2016] [Accepted: 03/04/2016] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND Green tea is believed to have beneficial effects in the prevention and treatment of acne. OBJECTIVE To examine the effects of a decaffeinated green tea extract (GTE), providing a daily dose of 856 mg of epigallocatechin gallate (EGCG) upon women with post-adolescent acne. METHODS A randomized, double-blind, placebo-controlled clinical trial was conducted from May 2012 through October 2013. A final group of 80 subjects were randomly assigned to receive either 1500 mg of decaffeinated GTE or placebo (cellulose) daily for 4 weeks. Inflammatory lesion counts were used as the major outcome measurement. At baseline and after 4 weeks of treatment, anthropometric measurements, fasting glucose levels and a lipid profile were measured from both groups. RESULTS Sixty-four of 80 women, from 25 to 45 years of age with moderate-to-severe acne completed the study. Statistically significant differences were noted in inflammatory lesion counts distributed on the nose, periorally and on the chin between the two groups. However, there were no significant differences between groups for total lesion counts. Within-group comparison revealed that the GTE group had significant reductions in inflammatory lesions distributed on the forehead and cheek, and significant reductions in total lesion counts. GTE resulted in significant reductions in total cholesterol levels within the GTE group. CONCLUSIONS GTE resulted in significant reductions in lesions located on the nose, perioral area and chin. More research is required to determine whether a decaffeinated GTE standardized for EGCG content will provide clinical benefits in women with post-adolescent acne.
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Influenza A plasma and serum virus antibody detection comparison in dogs using blocking enzyme-linked immunosorbent assay. Vet World 2015; 8:580-3. [PMID: 27047138 PMCID: PMC4774716 DOI: 10.14202/vetworld.2015.580-583] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2014] [Revised: 03/31/2015] [Accepted: 04/07/2015] [Indexed: 11/18/2022] Open
Abstract
Background and Aim: The influenza A virus (IAV) is an important zoonotic pathogen with infections also reported in dogs. IAV infections can be detected through the presence of antibodies using the enzyme-linked immunosorbent assay (ELISA). Serum is the only standard sample source; however, there is no information on the availability of other sample sources for IAV antibody detection in dogs. Compared with serum, plasma is more widely employed in most animal hospitals. The object of this study is to investigate whether plasma collected in ethylenediaminetetraacetic acid (EDTA) tubes (EDTA plasma) or heparin tubes (heparin plasma) could be used in the ELISA protocol instead of serum for IAV antibody detection in dogs. Materials and Methods: Totally, 82 matched EDTA plasma and serum sample pairs and 79 matched heparin plasma and serum sample pairs were employed using blocking enzyme-linked immunosorbent assay (bELISA). The agreement and correlation between the plasma (EDTA or heparin plasma) and serum were assessed using the agreement index kappa (kD) calculation and Pearson correlation coefficient, respectively. Results: The agreement index kD of EDTA plasma and serum was 1.0, and that of heparin plasma and serum was 0.85. The Pearson correlation coefficient of EDTA plasma and serum was 0.87 (p<0.01), and that of heparin plasma and serum was 0.82 (p<0.01). Conclusion: The results proved that plasma, especially EDTA plasma, could be substituted for serum in the bELISA test. This might greatly expand the clinical applicability of IAV antibody detection in dogs.
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Control of metamorphic buffer structure and device performance of In(x)Ga(1-x)As epitaxial layers fabricated by metal organic chemical vapor deposition. NANOTECHNOLOGY 2014; 25:485205. [PMID: 25396303 DOI: 10.1088/0957-4484/25/48/485205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Using a step-graded (SG) buffer structure via metal-organic chemical vapor deposition, we demonstrate a high suitability of In0.5Ga0.5As epitaxial layers on a GaAs substrate for electronic device application. Taking advantage of the technique's precise control, we were able to increase the number of SG layers to achieve a fairly low dislocation density (∼10(6) cm(-2)), while keeping each individual SG layer slightly exceeding the critical thickness (∼80 nm) for strain relaxation. This met the demanded but contradictory requirements, and even offered excellent scalability by lowering the whole buffer structure down to 2.3 μm. This scalability overwhelmingly excels the forefront studies. The effects of the SG misfit strain on the crystal quality and surface morphology of In0.5Ga0.5As epitaxial layers were carefully investigated, and were correlated to threading dislocation (TD) blocking mechanisms. From microstructural analyses, TDs can be blocked effectively through self-annihilation reactions, or hindered randomly by misfit dislocation mechanisms. Growth conditions for avoiding phase separation were also explored and identified. The buffer-improved, high-quality In0.5Ga0.5As epitaxial layers enabled a high-performance, metal-oxide-semiconductor capacitor on a GaAs substrate. The devices displayed remarkable capacitance-voltage responses with small frequency dispersion. A promising interface trap density of 3 × 10(12) eV(-1) cm(-2) in a conductance test was also obtained. These electrical performances are competitive to those using lattice-coherent but pricey InGaAs/InP systems.
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Body mass index is negatively associated with acne lesion counts in Taiwanese women with post-adolescent acne. J Eur Acad Dermatol Venereol 2014; 29:2046-50. [PMID: 25266447 DOI: 10.1111/jdv.12754] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 08/18/2014] [Indexed: 11/30/2022]
Abstract
BACKGROUND Acne in adult women tends to be chronic, refractory to treatment and associated with psychosocial problems. Body mass index (BMI) has been reported to be a risk factor for acne in school children and adolescents, but not in adult women. OBJECTIVES The aim of this study was to demonstrate the relationship between BMI and acne lesion counts in women with post-adolescent acne. METHODS Hundred and four women between 25 and 45 years of age, with moderate or severe acne vulgaris were enrolled in this study. The main outcome evaluated was the number of acne lesions, which were then assessed using multiple linear regression analysis. RESULTS The coefficients of multiple regression analysis with stepwise model showed that BMI (β = -0.36; p = 0.001) and family history (β = 0.21; p = 0.04) were the main predictors of the number of acne lesions. CONCLUSION Initial findings indicate that BMI is negatively associated with the number of acne lesions in Taiwanese women with moderate to severe post-adolescent acne.
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Differences in characteristics of men with localised prostate cancer who demonstrate low, intermediate or high prostate-specific antigen velocity. Intern Med J 2013; 42:374-80. [PMID: 21395960 DOI: 10.1111/j.1445-5994.2011.02473.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Current diagnostic tools are inadequate for reliable prediction of prostate cancer (PCa) aggressiveness in patients with localised disease. This results in many patients being exposed to potentially unnecessary invasive treatment and its associated morbidities. In order to develop appropriate treatment strategies, it is essential to understand the differences between patients who will develop aggressive disease and those who will not. METHODS A longitudinal study was conducted in men with localised PCa on active surveillance for their disease in which 140 subjects were followed every 3 months for up to 5 years. Change in prostate-specific antigen (PSA) over time (PSA velocity) was used as a marker for PCa progression. Subjects were categorised as slow, intermediate and fast progressors based on tertiles of PSA velocity. Differences in baseline markers were investigated using logistic regressions. Two approaches were used, slow progressors were compared with fast progressors (model 1) and slow progressors were compared with combination of intermediate and fast progressors (model 2). RESULTS Aspirin was negatively associated with high PSA velocity in model 1 (odds ratio (95% confidence interval): 0.24 (0.06, 0.94), P-value = 0.04) and model 2 (odds ratio = 0.22 (0.08, 0.59), P-value = 0.003), whereas smoking was positively associated with high PSA velocity in model 1 (1.03 (0.92, 1.13), P-value = 0.01). CONCLUSIONS These findings highlight the role of aspirin and smoking in PCa progression. They have potential towards risk stratification as well as PCa prevention and hence need to be investigated further.
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Association of obesity and smoking with PSA and PSA velocity in men with prostate cancer. Am J Mens Health 2011; 5:272-8. [PMID: 21613377 DOI: 10.1177/1557988310390030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Significant number of prostate tumors are slow growing and could probably be left untreated. However, many are aggressive and can spread rapidly causing patient suffering and/or death. Current technology does not allow physicians to differentiate between slow growing and aggressive tumors at diagnosis. Hence, many patients are exposed to invasive treatment and its associated morbidities such as incontinence and impotence. Markers that enable differentiation between slow and fast progressing cancer will allow physicians to prevent unnecessary treatments on men who may not need them, and focus on the men with aggressive disease. A longitudinal study was conducted (N = 140) using mixed effects regression models to determine the association of obesity and smoking toward prostate cancer progression. These models account for correlation because of repeated measures over time, thus, using maximum amount of information provided by the subject. Estimates thus obtained are more robust and reliable than those obtained using data from a single time point. Rate of change of prostate-specific antigen (PSA) over time (PSA velocity) was used as a measure of prostate cancer progression. Results indicate that PSA velocity of overweight and obese subjects (0.59 and 1.05 ng/mL/year) was not significantly different as compared with normal weight subjects (p values .91 and .31, respectively). For men in the highest tertile of pack-years of smoking, PSA velocity was significantly higher as compared with never smokers 1.57 ng/mL/year (p = .04). Further studies with larger sample sizes and study designs specific to above exposures are needed before recommendations can be made to reduce weight or reduce/quit smoking.
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Dose-dependent effects of selenized yeast on total selenium levels in prostatic tissue of men with prostate cancer. Nutr Cancer 2011; 63:1-5. [PMID: 21128179 DOI: 10.1080/01635581.2010.516476] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Effect of caffeine, norfloxacin and nimesulide on heartbeat and VEGF expression of zebrafish larvae. JOURNAL OF ENVIRONMENTAL BIOLOGY 2011; 32:179-183. [PMID: 21882652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The use of pharmaceuticals during pregnancy may causes abnormalities to the embryo. Sometime the drug also effect to the new born if the drug transferred through lactation. We have used zebrafish model to see the effect of some pharmaceuticals on embryos and larvae. Three drugs, caffeine, norfloxacin and nimesulide, were used for this study to see the effect mainly the hatching rate of eggs, heart beat rate and the vascular endothelial growth factor (VEGF) expression of the larvae. VEGF is an important signaling protein that involved generating the new blood vessels during embryonic development. We have used 10, 20, 50, 100 microg ml(-1) concentrations of all the drugs to see the effect. No significant mortality or malformations were observed in zebrafish embryos. Hatching was stared from 60 hr. In control group, 91% hatching rate was observed. Lowest hatching rate was observed using highest concentration of norfloxacin (100 microg ml(-1)) and nimesulide (100 microg ml(-1)) i.e. 55 and 56% respectively. In control group, 110 to 115 heart beat rate was counted per minute. Significantly higher heart beat was observed in caffeine treated group which is 125 to 140 min(-1) Lower heart beat was noted in nimesulide treated group which is 100 min(-1). We have tried to observe the possible effect of VEGF of the larvae by these three drugs. Expression of VEGF was very low in caffeine treated group. Almost no VGF expression was observe in 100 microg ml(-1) caffeine treated group. These studies suggest that there is a possibility that high dosage of caffeine can harm the unborn baby or new born babies, if the mothers use caffeine.
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A hypothetical relationship between the nuclear reprogramming factors for induced pluripotent stem (iPS) cells generation--bioinformatic and algorithmic approach. Med Hypotheses 2010; 76:507-11. [PMID: 21195557 DOI: 10.1016/j.mehy.2010.12.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2010] [Revised: 07/11/2010] [Accepted: 12/03/2010] [Indexed: 11/26/2022]
Abstract
A hypothetical evolutionary relationship was generated between the nuclear reprogramming factors for induced pluripotent stem (iPS) cells generation. Utilizing bioinformatics techniques, sequence analyses and phylogenetic tree algorithms, a comparative study has been performed to understand the evolutionary relationship of human nuclear reprogramming factors of induced pluripotent stem cells (iPSCs) generation. Among the total six nuclear reprogramming factors, the four reprogramming factors (SOX2, C-MYC, KLF4, and LIN28) have significant evolutionary origin. Our study shows SOX2 and C-MYC have evolutionary relationship and common point of origin. Likewise, KLF4 and LIN28 are having evolutionary relationship and have common point of origin. Based on these evidences, we propose that our study may be a great help to the future researchers to understand the mechanism(s) as well as pathway of nuclear reprogramming process.
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LRRK2 and the stress response: interaction with MKKs and JNK-interacting proteins. NEURODEGENER DIS 2010; 7:68-75. [PMID: 20173330 DOI: 10.1159/000285509] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Increasing evidence supports a putative link between LRRK2 function and the MAP kinase cascades. We recently demonstrated that LRRK2 binds to MKK6, -3, and -7. Previous studies demonstrated that scaffold proteins are essential in the regulation of subcellular localization of stress kinase complexes. The c-jun NH2-terminal kinase (JNK)-interacting proteins (JIPs) are a group of scaffold proteins that play an important role in the regulation of MAP kinase signaling cascades. JIP1-3 are known to regulate the specificity and localization of the JNK pathway, while JIP4 is a specific scaffolding protein for the p38 pathway. We demonstrate that LRRK2 binds to JIP1-4, and is associated with increased levels of total JIP1, -3, -4, oligomeric JIP and ubiquitinated JIP. These results are consistent with a putative role of LRRK2 in regulating the stress kinase cascade.
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Future prospects of nanoparticles on brain targeted drug delivery. J Neurooncol 2008; 93:285-6. [PMID: 19048187 DOI: 10.1007/s11060-008-9759-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2007] [Accepted: 11/03/2008] [Indexed: 10/21/2022]
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Suitability of surface acoustic wave oscillators fabricated using low temperature-grown AlN films on GaN/sapphire as UV sensors. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2008; 55:489-493. [PMID: 18334354 DOI: 10.1109/tuffc.2008.666] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Epitaxial AlN films were prepared on GaN/sapphire using a helicon sputtering system at the low temperature of 300 degrees C. Surface acoustic wave (SAW) devices fabricated on AlN/GaN/sapphire exhibited superior characteristics compared with those made on GaN/sapphire. An oscillator using an AlN/GaN/sapphirebased SAW device is presented. The oscillation frequency decreased when the device was illuminated by ultraviolet (UV) radiation, and the downshift of the oscillation frequency increased with the illuminating UV power density. The results showed that the AlN/GaN/sapphire-layered structure SAW oscillators are suitable for visible blind UV detection and opened up the feasibility of developing remote UV sensors for different ranges of wavelengths on the III-nitrides.
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Abstract
This study examined the concentrations and the relationships of soluble leptin receptor (sLR) and leptin levels among both physically active people and lean sedentary persons. Information collected for this study came from twelve joggers (JOG), ten weight trainers (WET) and eleven lean sedentary persons (CON). Regular exercisers were defined as those who consistently participated in jogging or weight training 30 minutes a day, at least four times a week, for a period of no less than three years prior to the study. The CON group was defined as exercising, at most, one time per week, less than 20 minutes each time if at all. Leptin and sLR were analyzed using enzyme-linked immunosorbent assay. The results show the BMI of the WET group to be higher than the other groups, yet their percent body fat was not significantly different. Although sLR levels of the JOG group were higher than the WET and CON groups, their free leptin index (FLI) did not show a significant difference. The sLR levels for joggers were higher than the weight trainers. The sLR concentration or the ratio of sLR to fat mass may be an alternative index to FLI for comparing physically active and lean people.
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Equilibrium and kinetics of metal biosorption by sludge from a biological nutrient removal system. ENVIRONMENTAL TECHNOLOGY 2007; 28:453-62. [PMID: 17500320 DOI: 10.1080/09593332808618806] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
This study investigated the biosorption kinetics and equilibrium of cadmium, nickel and zinc by activated sludge from a biological nutrient removal (BNR) process. A series of batch experiments with different initial metal concentrations were conducted to determine the metal removal in BNR sludge. The harvested sludges were from a continuous-flow anaerobic-anoxic-oxic (A2O) system operated under a 10 days of sludge retention time. Batch tests were specially designed to isolate the precipitation effects of metal ions in solution so as to compare the isotherm constants of biosorption with and without precipitation isolation. Experimental results revealed that BNR sludge exhibited two stages of biosorption, i.e., passive and then active uptake, for all three metals. The biosorption kinetic data of three tested metals can be effectively simulated by pseudo-second-order rate equations. Besides, the biosorption isotherm showed that metal biosorption behavior was statistically in agreement with the Freundlich model. The capacity constants k of the Freundlich model for Cd, Ni and Zn are 0.50, 0.23 and 0.41; the affinity constants 1 / n are 0.96, 0.81 and 0.31, respectively. Additionally, precipitation behaviors of metals obviously should be carefully examined during biosorption batch tests with activated sludge; otherwise the biosorption effect could be significantly overestimated.
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Phase II study of weekly vinorelbine and 24-h infusion of high-dose 5-fluorouracil plus leucovorin as first-line treatment of advanced breast cancer. Br J Cancer 2005; 92:1013-8. [PMID: 15770209 PMCID: PMC2361932 DOI: 10.1038/sj.bjc.6602469] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
We prospectively investigated the efficacy and safety of combining weekly vinorelbine (VNB) with weekly 24-h infusion of high-dose 5-fluorouracil (5-FU) and leucovorin (LV) in the treatment of patients with advanced breast cancer (ABC). Vinorelbine 25 mg m−2 30-min intravenous infusion, and high-dose 5-FU 2600 mg m−2 plus LV 300 mg m−2 24-h intravenous infusion (HDFL regimen) were given on days 1 and 8 every 3 weeks. Between June 1999 and April 2003, 40 patients with histologically confirmed recurrent or metastatic breast cancer were enrolled with a median age of 49 years (range: 36–68). A total of 25 patients had recurrent ABC, and 15 patients had primary metastatic diseases. The overall response rate for the intent-to-treat group was 70.0% (95% CI: 54–84%) with eight complete responses and 20 partial responses. All 40 patients were evaluated for survival and toxicities. Among a total of 316 cycles of VNB–HDFL given (average: 7.9: range: 4–14 cycles per patient), the main toxicity was Gr3/4 leucopenia and Gr3/4 neutropenia in 57 (18.0%) and 120 (38.0%) cycles, respectively. Gr1/2 infection and Gr1/2 stomatitis were noted in five (1.6%) and 59 (18.7%) cycles, respectively. None of the patients developed Gr3/4 stomatitis or Gr3/4 infection. Gr2/3 and Gr1 hand–foot syndrome was noted in two (5.0%) and 23 (57.5%) patients, respectively. Gr1 sensory neuropathy developed in three patients. The median time to progression was 8.0 months (range: 3–25.5 months), and the median overall survival was 25.0 months with a follow-up of 5.5 to 45+ months. This VNB–HDFL regimen is a highly active yet well-tolerated first-line treatment for ABC.
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A feasibility study on the predictive emission monitoring system applied to the Hsinta power plant of Taiwan Power Company. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2003; 53:1022-1028. [PMID: 12943322 DOI: 10.1080/10473289.2003.10466241] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The continuous emission monitoring system (CEMS) can monitor flue gas emissions continuously and instantaneously. However, it has the disadvantages of enormous cost, easily producing errors in sampling periods of bad weather, lagging response in variable ambient environments, and missing data in daily zero and span tests and maintenance. The concept of a predictive emission monitoring system (PEMS) is to use the operating parameters of combustion equipment through thermodynamic or statistical methods to construct a mathematic model that can predict emissions by a computer program. The goal of this study is to set up a PEMS in a gas-fired combined cycle power generation unit at the Hsinta station of Taiwan Power Co. The emissions to be monitored include nitrogen oxides (NOx) and oxygen (O2) in flue gas. The major variables of the predictive model were determined based on the combustion theory. The data of these variables then were analyzed to establish a regression model. From the regression results, the influences of these variables are discussed and the predicted values are compared with the CEMS data for accuracy. In addition, according to the cost information, the capital and operation and maintenance costs for a PEMS can be much lower than those for a CEMS.
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Ventricular asystole and complete heart block after thoracic epidural analgesia for thymectomy. Eur J Anaesthesiol 2002; 19:460-2. [PMID: 12094924 DOI: 10.1017/s0265021502220748] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Microbial iron respiration can protect steel from corrosion. Appl Environ Microbiol 2002; 68:1440-5. [PMID: 11872499 PMCID: PMC123774 DOI: 10.1128/aem.68.3.1440-1445.2002] [Citation(s) in RCA: 153] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2001] [Accepted: 12/12/2001] [Indexed: 11/20/2022] Open
Abstract
Microbiologically influenced corrosion (MC) of steel has been attributed to the activity of biofilms that include anaerobic microorganisms such as iron-respiring bacteria, yet the mechanisms by which these organisms influence corrosion have been unclear. To study this process, we generated mutants of the iron-respiring bacterium Shewanella oneidensis strain MR-1 that were defective in biofilm formation and/or iron reduction. Electrochemical impedance spectroscopy was used to determine changes in the corrosion rate and corrosion potential as a function of time for these mutants in comparison to the wild type. Counter to prevailing theories of MC, our results indicate that biofilms comprising iron-respiring bacteria may reduce rather than accelerate the corrosion rate of steel. Corrosion inhibition appears to be due to reduction of ferric ions to ferrous ions and increased consumption of oxygen, both of which are direct consequences of microbial respiration.
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Importance of early phase insulin secretion to intravenous glucose tolerance in subjects with type 2 diabetes mellitus. J Clin Endocrinol Metab 2001; 86:5824-9. [PMID: 11739446 DOI: 10.1210/jcem.86.12.8105] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Insulin secretion is impaired in type 2 diabetes with the early response being essentially absent. The loss of this early insulin secretion is hypothesized to be important in the deterioration of glucose tolerance. To determine whether enhancement of the early-phase insulin response can enhance glucose tolerance, we administered 1) 120 mg nateglinide, an insulinotropic agent that enhances early insulin secretion; 2) 10 mg glyburide, which enhances the later phases of insulin secretion; or 3) placebo in random order to 21 subjects with type 2 diabetes (14 males and 7 females; aged 59.2 +/- 2.1 yr, x +/- SEM; body mass index 29.7 +/- 1.0 kg/m(2); fasting plasma glucose 8.1 +/- 0.1 mM). beta-Cell function was quantified as the incremental area under the curve for different time periods for the 5 h following iv glucose administration and glucose tolerance as the glucose disappearance constant (Kg) from 10 to 60 min. Insulin release commenced immediately after nateglinide administration, even before glucose injection, but this was not observed with glyburide. Both nateglinide and glyburide enhanced glucose-induced insulin release, compared with placebo (area under the curve -15-300 min: nateglinide 23,595 +/- 11,212 pM/min, glyburide 54,556 +/- 15,253 pM/min, placebo 10,242 +/- 2,414 pM/min). The profiles of insulin release demonstrated significant enhancement of release between -15 and 30 min for nateglinide, compared with glyburide and between 60 and 300 min for glyburide over nateglinide. Kg increased by 15% with nateglinide (0.87 +/- 0.04%/min), but it did not increase significantly with glyburide (0.79 +/- 0.04%/min), compared with placebo (0.76 +/- 0.04%/min). The enhancement of insulin release by glyburide resulted in a lower minimal glucose concentration with glyburide (3.8 +/- 0.2 mM), compared with nateglinide (5.0 +/- 0.2 mM) and placebo (5.9 +/- 0.2 mM). Thus, enhancement of the early phase of insulin secretion improves iv glucose tolerance, whereas delaying it by 30 min results in a slower rate of glucose disappearance for the first 2 h after iv glucose administration. Further, the differences in the kinetics of nateglinide and glyburide action results in continued insulin release with glyburide despite the fact that glucose levels have returned to basal, thus resulting in a further reduction in glucose levels and a lower nadir.
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Abstract
We compare and contrast several different methods for estimating the effect of treatment when responses are paired binomial observations. The ratio of binomial probabilities is the parameter of interest, while the binomial probabilities are nuisance parameters which may vary between pairs. The application is a meta-analysis of the treatment of rectal cancer, with observations in each study indicating the number of recurrences of the cancer in each of two groups, one with radiation therapy and one without. The ratio of the probabilities of recurrence in the radiation to non-radiation groups is of substantive interest, and is modelled as a logistic or complementary log-log function of an unknown linear combination of the covariates. The three methods we consider are maximum likelihood, a Bayesian approach and an approach based on estimating equations. For the MLE and Bayesian approach the potentially large number of nuisance parameters are estimated together with the parameters of interest, whereas for the estimating equation approach only the parameters of interest are estimated. A simulation study is performed to compare the methods and evaluate the impact of overdispersion.
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Solution structure of a Kunitz-type chymotrypsin inhibitor isolated from the elapid snake Bungarus fasciatus. J Biol Chem 2001; 276:45079-87. [PMID: 11562364 DOI: 10.1074/jbc.m106182200] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Bungarus fasciatus fraction IX (BF9), a chymotrypsin inhibitor, consists of 65 amino acid residues with three disulfide bridges. It was isolated from the snake venom of B. fasciatus by ion-exchange chromatography and belongs to the bovine pancreatic trypsin inhibitor (BPTI)-like superfamily. It showed a dissociation constant of 5.8 x 10(-8) m with alpha-chymotrypsin as measured by a BIAcore binding assay system. The isothermal titration calorimetry revealed a 1:1 binding stoichiometry between this inhibitor and chymotrypsin and apparently no binding with trypsin. We further used CD and NMR to determine the solution structure of this venom-derived chymotrypsin inhibitor. The three-dimensional NMR solution structures of BF9 were determined on the basis of 582 restraints by simulated annealing and energy minimization calculations. The final set of 10 NMR structures was well defined, with average root mean square deviations of 0.47 A for the backbone atoms in the secondary structure regions and 0.86 A for residues The side chains of Phe(23), Tyr(24), Tyr(25), Phe(35), and Phe(47) exhibited many long-range nuclear Overhauser effects and were the principal components of the hydrophobic core in BF9. To gain insight into the structure-function relationships among proteins in the BPTI-like superfamily, we compared the three-dimensional structure of BF9 with three BPTI-like proteins that possess distinct biological functions. These proteins possessed similar secondary structure elements, but the loop regions and beta-turn were different from one another. Based on residues at the functional site of each protein, we suggest that the flexibility, rigidity, and variations of the amino acid residues in both the loop and beta-turn regions are related to their biological functions.
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The p53 codon 249 mutant--derived from human functional adrenal tumors--can modify the cell shape of normal adrenocortical transfected cells. Cancer Lett 2001; 170:63-71. [PMID: 11448536 DOI: 10.1016/s0304-3835(01)00568-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Our previous study has indicated that p53 gene mutation occurred in 73% of human functional adrenal tumors, and the mutation hot spots were focused on codons 100, 102 (exon 4), and 249 (exon 7). Furthermore, a transcriptional activity study revealed that the mutant p53 protein derived from human functional adrenal tumors lost 90% transcriptional activity and the ability to bind with the p53 sequence. In order to investigate the influence of the mutant protein extracted from adrenocortical tumors on normal adrenal cells, we first cloned p53 cDNA from the human primary aldosteronism and constituted it with isopropyl thiogalactoside (IPTG) inducible expression vector as recombinant plasmid. The recombinant plasmid was then transfected to normal bovine adrenocortical cells through electroporation. The results showed that the p53 protein mutations at codons 100 and 102 could neither affect the cell morphology nor enable cell growth on the soft agar. In addition, no significant difference was found in cortisol level between the p53 transfected and the control cells. On the other hand, cell morphological changes and cell proliferation rate increase were observed when we used IPTG to induce the expression of the p53 protein, which mutated at codon 249, in adrenocortical cells. The cell morphology changes included less flattened and decreased elongation when compared to non-transfected cells. However, the cortisol level in transfected cells was not affected by the p53 mutants. Taken together, we concluded that the mutant p53 protein indeed participates in adrenal carcinogenesis; however, it has no influence on hormone production and secretion.
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Population pharmacokinetics of everolimus in de novo renal transplant patients: impact of ethnicity and comedications. Clin Pharmacol Ther 2001; 70:247-54. [PMID: 11557912 DOI: 10.1067/mcp.2001.118022] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Everolimus is a macrolide immunosuppressant intended for acute rejection prophylaxis after kidney transplantation. METHODS A total of 5260 blood samples were collected in the context of two randomized, double-blind, multicenter efficacy trials in 673 patients over a 6-month period after kidney transplantation. The data were evaluated in a nonlinear mixed-effects model. The influence of demographic characteristics (age, weight, sex, and ethnicity) and of comedications on everolimus exposure was explored. RESULTS For a reference 44-year-old, 71-kg Caucasian kidney allograft recipient receiving everolimus as part of a cyclosporine (INN, ciclosporin)-prednisone immunosuppressive regimen, the absorption rate constant was 6.07 h(-1) (standard error [SE], 0.70 h(-1)), the apparent clearance was 8.8 L/h (SE, 0.2 L/h), and the apparent central distribution volume was 110 L (SE, 5 L). There were no clinically relevant influences of age, weight, or sex on clearance. No significant difference in clearance was detected for Asian patients, whereas black patients had an average clearance that was 20% higher than that of nonblack patients. Patients concomitantly receiving erythromycin or azithromycin had an average 19% lower clearance. One patient receiving itraconazole had a 74% reduction in clearance. After we accounted for covariates, the remaining interindividual variability in clearance was 27% and the variability for distribution volume was 36%. The combined intraindividual and assay/measurement residual error in everolimus blood concentrations was 31%. CONCLUSIONS Dose adjustment of everolimus on the basis of weight does not appear necessary. Black patients may need a higher dose to achieve exposure that is similar to that of nonblack patients. Concomitant administration of potent inhibitors of the cytochrome P450 isozyme CYP3A may reduce everolimus clearance and increase its blood concentrations.
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Pathogens in the middle ear effusion of children with persistent otitis media: implications of drug resistance and complications. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2001; 34:190-4. [PMID: 11605810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Acute otitis media (AOM) is the most common disease for which pediatricians prescribe antimicrobial agents. Middle ear fluid were collected from 243 children with AOM that failed to respond to a previous course of antimicrobial therapy and who had then received myringotomy from September 1997 through August 1999. Bacterial cultures were done and antimicrobial susceptibilities were analyzed. Streptococcus pneumoniae (21.8%) was the most common causative organism, followed by Haemophilus influenzae (10.2%), Staphylococcus aureus (7%), and Pseudomonas aeruginosa (1.8%), while Moraxella catarrhalis (0.7%) and group A beta-hemolytic streptococcus (0.2%) were rarely isolated. In patients whose condition failed to improve after a course of antibiotic treatment, drug resistance became a serious problem. Fourteen percent of the patients in this series had complications, which included recurrent AOM, persistent middle ear effusion necessitating ventilation tube insertion, hearing impairment, mastoiditis, meningitis, chronic otitis media, brain abscess, and sepsis. Possible risk factors such as young age, male sex, underlying diseases, and a culture of S. pneumoniae or H. influenzae were not significantly associated with an increased incidence of complications. More stringent diagnosis and the correct choice of antibiotic treatment combined with the introduction of potential virus and bacterial vaccines are promising ways to reduce the morbidity of AOM in children.
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Abstract
Abamectin is widely used as an insecticide and an anthelmintic. A previous report indicated that abamectin was used to commit suicide and led to death in Taiwan. This investigation focused on the toxicological effects of abamectin on serum aspartate aminotransferase (AST) and nitrate/nitrite (NO) levels in rats. After rats were gavaged with abamectin ranging from 1 to 20 mg/kg/body weight, AST and NO levels were examined within 12 h. AST and NO levels were elevated in abamectin-dosed rats in a dose-dependent manner. The least increase of AST corresponded to the highest enhancement of NO release at 6 h. A negative correlation coefficient (r=-0.55) between AST and NO was found. Both NG-nitro-L-arginine-methyl ester and aminoguanidine, inhibitors of nitric oxide synthase, increased the AST level induced by abamectin. These findings suggest that NO may be involved in the alteration of AST release induced by abamectin in rats.
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Phase I clinical trial of curcumin, a chemopreventive agent, in patients with high-risk or pre-malignant lesions. Anticancer Res 2001; 21:2895-900. [PMID: 11712783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Curcumin (diferuloylmethane), a yellow substance from the root of the plant Curcuma longa Linn., has been demonstrated to inhibit carcinogenesis of murine skin, stomach, intestine and liver. However, the toxicology, pharmacokinetics and biologically effective dose of curcumin in humans have not been reported. This prospective phase-I study evaluated these issues of curcumin in patients with one of the following five high-risk conditions: 1) recently resected urinary bladder cancer; 2) arsenic Bowen's disease of the skin; 3) uterine cervical intraepithelial neoplasm (CIN); 4) oral leucoplakia; and 5) intestinal metaplasia of the stomach. Curcumin was taken orally for 3 months. Biopsy of the lesion sites was done immediately before and 3 months after starting curcumin treament. The starting dose was 500 mg/day. If no toxicity > or = grade II was noted in at least 3 successive patients, the dose was then escalated to another level in the order of 1,000, 2,000, 4,000, 8,000, and 12,000 mg/day. The concentration of curcumin in serum and urine was determined by high pressure liquid chromatography (HPLC). A total of 25 patients were enrolled in this study. There was no treatment-related toxicity up to 8,000 mg/day. Beyond 8,000 mg/day, the bulky volume of the drug was unacceptable to the patients. The serum concentration of curcumin usually peaked at 1 to 2 hours after oral intake of crucumin and gradually declined within 12 hours. The average peak serum concentrations after taking 4,000 mg, 6,000 mg and 8,000 mg of curcumin were 0.51 +/- 0.11 microM, 0.63 +/- 0.06 microM and 1.77 +/- 1.87 microM, respectively. Urinary excretion of curcumin was undetectable. One of 4 patients with CIN and 1 of 7 patients with oral leucoplakia proceeded to develop frank malignancies in spite of curcumin treatment. In contrast, histologic improvement of precancerous lesions was seen in 1 out of 2 patients with recently resected bladder cancer, 2 out of 7 patients of oral leucoplakia, 1 out of 6 patients of intestinal metaplasia of the stomach, I out of 4 patients with CIN and 2 out of 6 patients with Bowen's disease. In conclusion, this study demonstrated that curcumin is not toxic to humans up to 8,000 mg/day when taken by mouth for 3 months. Our results also suggest a biologic effect of curcumin in the chemoprevention of cancer.
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Factors influencing the success of breast-feeding. ACTA PAEDIATRICA TAIWANICA = TAIWAN ER KE YI XUE HUI ZA ZHI 2001; 42:189-90. [PMID: 11550405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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Analysis of 200 food items for benzo[a]pyrene and estimation of its intake in an epidemiologic study. Food Chem Toxicol 2001; 39:423-36. [PMID: 11313108 DOI: 10.1016/s0278-6915(00)00158-7] [Citation(s) in RCA: 327] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Animal studies have shown that dietary intake of benzo[a]pyrene (BaP), a polycyclic aromatic hydrocarbon (PAH), causes increased levels of tumors at several sites, particularly in the upper gastrointestinal tract. However, the role of dietary intake of BaP and cancer in humans is not clear. We created a BaP database of selected food products that could be linked to Food Frequency Questionnaires (FFQs) to estimate BaP intake. BaP levels were measured for each food line-item (composite samples) which consisted of a variety of foods in a FFQ. Composite sample parts were derived from the Second National Health and Nutrition Examination Survey (NHANES II) which represents the most common food items consumed by the general population. Meat samples were cooked by different techniques in controlled conditions, and by various restaurants and fast-food chains. Non-meat products were purchased from the major national supermarket chains. The quantities of BaP were measured using a thin-layer chromatography (TLC)/spectrofluorometer technique and were highly correlated with both BaP (r=0.99) [corrected] and sum of carcinogenic PAH (r=0.98) measured by HPLC technique. We linked our database to the results from a FFQ and estimated the daily BaP intake of various food items in 228 subjects in the Washington, DC metropolitan area. The highest levels of BaP (up to about 4 ng BaP/g of cooked meat) were found in grilled/barbecued very well done steaks and hamburgers and in grilled/barbecued well done chicken with skin. BaP concentrations were lower in meats that were grilled/barbecued to medium done and in all broiled or pan-fried meat samples regardless of doneness level. The BaP levels in non-meat items were generally low. However, certain cereals and greens (e.g. kale, collard greens) had levels up to 0.5 ng/g. In our population, the bread/cereal/grain, and grilled/barbecued meat, respectively, contributed 29 and 21 percent to the mean daily intake of BaP. This database may be helpful in initial attempts to assess dietary BaP exposures in studies of cancer etiology.
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1H, 13C and 15N resonance assignments and secondary structure of the cytotoxic protein RNase 4 from bullfrog Rana catesbeiana oocytes. JOURNAL OF BIOMOLECULAR NMR 2001; 20:93-94. [PMID: 11430762 DOI: 10.1023/a:1011255913840] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Significantly increased cortisol secretion in normal adrenocortical cells transfected with K-ras mutants derived from human functional adrenocortical tumors. DNA Cell Biol 2001; 20:231-8. [PMID: 11403720 DOI: 10.1089/104454901750219116] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Our previous study showed that the mutation hotspots of the K-ras proto-oncogene in human functional adrenocortical tumors are in codons 15, 16, 18, and 31, thus differing from the sites in other tumors. In addition, analyzing the K-Ras protein by a recombinant DNA technique showed that the activity of endogenic GTPase and the GTPase-activating protein (GAP)-binding ability were significantly decreased in patients with these tumors. The aim of this study was to understand whether those K-ras mutants, which were found only in human adrenocortical tumors, play an important role in these tumors. Thus, the mutant K-ras cDNA was constructed with mammalian expression vectors and transfected into normal adrenocortical cells. The amount of cortisol secreted by the transfected cells was 20 to 30 times that of normal cells. Furthermore, Northern blot analysis revealed that the expression of the three steroidogenesis-related genes P450(scc) (cholesterol side-chain cleavage enzyme), P450(C17) (17alpha-hydroxylase/17, 20-lyase), and P450(C21) (steroid 21-hydroxylase) gene increased in the transfected cells. The K-ras oncogene significantly increases cortisol secretion by normal adrenocortical cells.
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A pilot study of AFL-T (doxorubicin, 5-fluorouracil, leucovorin, and tamoxifen) combination chemotherapy for hormone-refractory prostate cancer. Anticancer Res 2001; 21:1385-90. [PMID: 11396219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
BACKGROUND Tamoxifen had been used to treat advanced prostate cancer with limited success. In vitro data suggested that tamoxifen could enhance the cytotoxic effect of chemotherapeutic agents, including doxorubicin, on prostate cancer cell lines. We applied this observation into a phase II trial for patients with hormone refractory prostate cancer (HRPC). PATIENTS AND METHODS The AFL-T regimen consisted of doxorubicin 30 mg/m2/day on day 1; 5-FU 2,000 mg/m2/day 24-hour infusion and leucovorin 200 mg/m2/day 24-hour infusion on days 15 and 29; tamoxifen 50 mg/m2 four times daily on days 1, 2, 16, 17, 30, and 31. The protocol was designed to be of low dose-intensity and tolerable to most HRPC patients who may have reduced bone marrow reserve and poor renal function. Between Feb. 1994 and April 1999, 17 patients (median age 67, range 60-81) with HRPC were enrolled. Extensive hormonal manipulations had been done prior to the chemotherapy. Three patients had measurable diseases, 14 had only bone metastases, and all had elevated PSA levels (median 498 ng/ml, range 7.4-3,970 ng/ml). RESULTS All 17 patients were eligible for analysis of toxicity. ECOG Grade III/IV leukopenia and thrombocytopenia occurred in 1 and 3 patients, respectively. There was no febrile neutropenia; there was no treatment-related mortality. Grade III/IV nausea, vomiting, mucositis, and diarrhea were noted in 0, 0, 1 and 0 patient, respectively. There was no venous thrombosis. One partial response, 1 stable disease, and 1 progressive disease were found in the three patients with measurable lesions. Eleven of the 17 patients (64.7%, 95% confidence interval: 41-88%) who were eligible for the evaluation of PSA response (PSA decrease > 50% for at least 6 weeks) were responders. The median overall and progression-free survivals were 13 and 7 months, respectively. Seventy-six percent of patients showed decreased analgesic usage or enhanced performance status. CONCLUSION AFL-T, that has a low toxicity profile, is comparable to most other active regimens in terms of the PSA response rate. Randomized trials are needed to determine if there exists a survival benefit for patients with HRPC.
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