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1.
Small ; : e2403013, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38874067

RESUMEN

Stabilizing liquid-liquid interfaces, whether between miscible or immiscible liquids, is crucial for a wide range of applications, including energy storage, microreactors, and biomimetic structures. In this study, a versatile approach for stabilizing the water-oil interface is presented using the morphological transitions that occur during the self-assembly of anionic, cationic, and nonionic surfactants mixed with fatty acid oils. The morphological transitions underlying this approach are characterized and extensively studied through small-angle X-ray scattering (SAXS), rheometry, and microscopy techniques. Dissipative particle dynamics (DPD) as a simulation tool is adopted to investigate these morphological transitions both in the equilibrium ternary system as well as in the dynamic condition of the water-oil interface. Such a versatile strategy holds promise for enhancing applications such as liquid-in-liquid 3D printing. Moreover, it has the potential to revolutionize a wide range of fields where stabilizing liquid-liquid interfaces not only offers unprecedented opportunities for fine-tuning nanostructural morphologies but also imparts interesting practical features to the resulting liquid shapes. These features include perfusion capabilities, self-healing, and porosity, which could have significant implications for various industries.

2.
Phys Rev Lett ; 130(11): 113203, 2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-37001111

RESUMEN

A Wannier-Stark optical lattice clock has demonstrated unprecedented measurement precision for optical atomic clocks. We present a systematic evaluation of the lattice light shift, a necessary next step for establishing this system as an accurate atomic clock. With precise control of the atomic motional states in the lattice, we report accurate measurements of the multipolar and the hyperpolar contributions and the operational lattice light shift with a fractional frequency uncertainty of 3.5×10^{-19}.

3.
Pediatr Crit Care Med ; 24(2): 123-132, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36521191

RESUMEN

OBJECTIVE: To perform a systematic review and meta-analysis of randomized controlled trials (RCTs) on the use of noninvasive ventilation (NIV) for acute respiratory failure (ARF) in pediatric patients. DATA SOURCES: We searched PubMed, EMBASE, the Cochrane Central Register of Clinical Trials, and Clinicaltrials.gov with a last update on July 31, 2022. STUDY SELECTION: We included RCTs comparing NIV with any comparator (standard oxygen therapy and high-flow nasal cannula [HFNC]) in pediatric patients with ARF. We excluded studies performed on neonates and on chronic respiratory failure patients. DATA EXTRACTION: Baseline characteristics, intubation rate, mortality, and hospital and ICU length of stays were extracted by trained investigators. DATA SYNTHESIS: We identified 15 RCTs (2,679 patients) for the final analyses. The intubation rate was 109 of 945 (11.5%) in the NIV group, and 158 of 1,086 (14.5%) in the control group (risk ratio, 0.791; 95% CI, 0.629-0.996; p = 0.046; I2 = 0%; number needed to treat = 31). Findings were strengthened after removing studies with intervention duration shorter than an hour and after excluding studies with cross-over as rescue treatment. There was no difference in mortality, and ICU and hospital length of stays. CONCLUSIONS: In pediatric patients, NIV applied for ARF might reduce the intubation rate compared with standard oxygen therapy or HFNC. No difference in mortality was observed.


Asunto(s)
Ventilación no Invasiva , Síndrome de Dificultad Respiratoria , Insuficiencia Respiratoria , Recién Nacido , Humanos , Niño , Oxígeno , Terapia por Inhalación de Oxígeno , Intubación , Síndrome de Dificultad Respiratoria/terapia , Cánula , Insuficiencia Respiratoria/terapia
4.
Sensors (Basel) ; 23(12)2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37420771

RESUMEN

Frequency-modulated continuous wave (FMCW) radar system synchronization using external clock signals can cause repeated Range-Doppler (R-D) map corruption when clock signal asynchronization problems occur between the transmitter and receiver. In this paper, we propose a signal processing method for the reconstruction of the corrupted R-D map owing to the FMCW radar's asynchronization. After calculating the image entropy for each R-D map, the corrupted ones are extracted and reconstructed using the normal R-D maps acquired before and after the individual maps. To verify the effectiveness of the proposed method, three target detection experiments were conducted: a human target detection in an indoor environment and a wide place and a moving bike-rider target detection in an outdoor environment. The corrupted R-D map sequence of observed targets in each case was reconstructed properly and showed the validity by comparing the map-by-map range and speed changes in the detected target with the ground-truth information of the target.


Asunto(s)
Radar , Procesamiento de Señales Asistido por Computador , Humanos , Ultrasonografía Doppler
5.
J Clin Psychopharmacol ; 42(6): 536-543, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36356202

RESUMEN

BACKGROUND: Corrected QT-interval (QTc) prolongation (QTP) is a rare but fatal adverse effect of antipsychotics. Clozapine is the only antipsychotic recommended for treatment of resistant schizophrenia; however, clozapine has been reported to cause QTP. We sought factors predictive of QTP in patients who had antipsychotic polypharmacy involving clozapine. We explored whether the clozapine blood concentration might predict QTP. METHODS: We included 133 patients with schizophrenia spectrum disorder who had antipsychotic polypharmacy involving clozapine. We used the χ2 and nonparametric tests to compare clozapine therapeutic drug monitoring (TDM) values and QTc-prolonged person (QTPP) status. Multivariate regression and mediator models were used to identify risk factors for QTPP status and QTP. RESULTS: In total, 111 patients were prescribed clozapine. The QTPP rates were 31.3% (20) for men and 23.2% (16) for women. Compared with the non-QTPP group, the QTPP group exhibited significantly higher daily dose of all antipsychotics including clozapine, a higher clozapine dose, and elevated clozapine and norclozapine TDM values. Furthermore, such patients were prescribed a greater number of antipsychotics. Multivariate logistic regression revealed that only the clozapine TDM value could be predictive factor for QTPP status (P = 0.018). A clozapine TDM value above the therapeutic range (>600 mg/dL) was associated with a high risk of QTPP status (adjusted odds ratio, 6.5; 95% confidence interval, 1.7-25.2; P = 0.006). The mediator model revealed that the clozapine TDM values completely mediated the association between the clozapine dose and the QTc interval. CONCLUSIONS: The clozapine blood concentration reliably predicts QTP in patients with clozapine use.


Asunto(s)
Antipsicóticos , Clozapina , Síndrome de QT Prolongado , Trastornos Psicóticos , Esquizofrenia , Masculino , Humanos , Femenino , Clozapina/uso terapéutico , Antipsicóticos/uso terapéutico , Trastornos Psicóticos/tratamiento farmacológico , Trastornos Psicóticos/complicaciones , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/complicaciones , Síndrome de QT Prolongado/inducido químicamente
6.
Phys Rev Lett ; 127(4): 043401, 2021 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-34355976

RESUMEN

We report the observation of matter-wave jet emission in a strongly ferromagnetic spinor Bose-Einstein condensate of ^{7}Li atoms. Directional atomic beams with |F=1,m_{F}=1⟩ and |F=1,m_{F}=-1⟩ spin states are generated from |F=1,m_{F}=0⟩ state condensates or vice versa. This results from collective spin-mixing scattering events, where spontaneously produced pairs of atoms with opposite momentum facilitates additional spin-mixing collisions as they pass through the condensates. The matter-wave jets of different spin states (|F=1,m_{F}=±1⟩) can be a macroscopic Einstein-Podolsky-Rosen state with spacelike separation. Its spin-momentum correlations are studied by using the angular correlation function for each spin state. Rotating the spin axis, the inter- and intraspin-momentum correlation peaks display a high-contrast oscillation, indicating collective coherence of the atomic ensembles. We provide numerical calculations that describe the experimental results at a quantitative level. Our Letter paves the way to generating macroscopic quantum entanglement with the spin and motional degree of freedom with massive particles. It has a wide range of applications from quantum information science to the fundamental studies of quantum entanglement.

7.
Proc Natl Acad Sci U S A ; 115(5): 847-854, 2018 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-29348199

RESUMEN

Cooling disordered compositionally asymmetric diblock copolymers leads to the formation of nearly spherical particles, each containing hundreds of molecules, which crystallize upon cooling below the order-disorder transition temperature (TODT). Self-consistent field theory (SCFT) reveals that dispersity in the block degrees of polymerization stabilizes various Frank-Kasper phases, including the C14 and C15 Laves phases, which have been accessed experimentally in low-molar-mass poly(isoprene)-b-poly(lactide) (PI-PLA) diblock copolymers using thermal processing strategies. Heating and cooling a specimen containing 15% PLA above and below the TODT from the body-centered cubic (BCC) or C14 states regenerates the same crystalline order established at lower temperatures. This memory effect is also demonstrated with a specimen containing 20% PLA, which recrystallizes to either C15 or hexagonally ordered cylinders (HEXC) upon heating and cooling. The process-path-dependent formation of crystalline order shapes the number of particles per unit volume, n/V, which is retained in the highly structured disordered liquid as revealed by small-angle X-ray scattering (SAXS) experiments. We hypothesize that symmetry breaking during crystallization is governed by the particle number density imprinted in the liquid during ordering at lower temperature, and this metastable liquid is kinetically constrained from equilibrating due to prohibitively large free energy barriers for micelle fusion and fission. Ordering at fixed n/V is enabled by facile chain exchange, which redistributes mass as required to meet the multiple particle sizes and packing associated with specific low-symmetry Frank-Kasper phases. This discovery exposes universal concepts related to order and disorder in self-assembled soft materials.

8.
Nano Lett ; 20(9): 6651-6659, 2020 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-32809835

RESUMEN

Tailoring the crystal orientation of poly(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE) has attracted widespread interest because of its effects on the ferroelectric properties required for various electronic devices. In this study, we investigated the epitaxial growth of PVDF-TrFE on a chitin film for developing triboelectric nanogenerators (TENGs). The crystallographic match between the chitin and PVDF-TrFE enables the development of the intended crystal orientation, with the PVDF-TrFE polarization axis aligned perpendicular to the substrate. In addition, the epitaxially grown PVDF-TrFE on chitin not only enhances the performance of the TENG but also increases the stability of the hygroscopic chitin film against water. The corresponding TENG exhibits a significantly higher output current compared to that of a nonepitaxial PVDF-TrFE/chitin film. Furthermore, the triboelectric sensors based on epitaxial PVDF-TrFE/chitin films allow the monitoring of subtle pressures, suggesting that tailoring the crystal orientation of PVDF-TrFE is a promising approach for developing high-performance TENGs.

9.
Nanotechnology ; 31(45): 455302, 2020 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-32702675

RESUMEN

A template with macroscopically aligned nanopatterns can be an effective vehicle for arranging nanoscale particles or rods in a particular orientation to achieve their anisotropic properties. A room-temperature process is also desirable for nanoscale patterning of heat-sensitive functional molecules such as organic fluorophores. Here, large-area orientation of nanodomains of block copolymers is demonstrated by simultaneous shearing and solvent vapor annealing at room temperature. The shear-aligned nanodomains are applied to a chemical template for nanoscale patterning of green fluorescent molecules. In addition, the grooved nanochannels obtained from the macroscopically aligned nanodomains work as a physical template for guiding Au nanorods to end-to-end assemblies which exhibit the polarization-dependent plasmonic extinction.

10.
J Nat Prod ; 83(11): 3354-3362, 2020 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-33073572

RESUMEN

2-Aryl/alkylbenzofurans, which constitute an important subclass of naturally occurring lignans and neolignans, have attracted extensive synthetic efforts due to their useful biological activities and significant pharmacological potential. Herein, we report a general and efficient approach to divergent 2-arylbenzofurans through a one-pot synthesis of versatile 2-bromobenzofurans as key intermediates. Using this approach, the first total synthesis of a series of trisubstituted and tetrasubstituted benzofurans bearing the hydroxyethyl unit, including the natural compounds isolated from Lavandula agustifolia (1-3) and their non-natural derivatives (4-8), was accomplished. We also report a modified synthesis of ailanthoidol, homoegonol, and egonol that enables the divergent synthesis of their derivatives for future exploration. Among these, the representative phenolic natural compound 2 and its derivatives 7 and 5 induced apoptotic cell death related poly(ADP-ribose) polymerase (PARP) cleavage in MCF74, A549, PC3, HepG2, and Hep3B cancer cell lines. Additionally, the tumor suppressor protein p53 was also induced in p53 wild type cancer cells.


Asunto(s)
Anisoles/química , Benzofuranos/síntesis química , Benzofuranos/farmacología , Lavandula/química , Anisoles/farmacología , Benzofuranos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ciclización , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Oxidación-Reducción , Análisis Espectral/métodos
11.
J Infect Chemother ; 26(9): 1011-1013, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32631735

RESUMEN

The assessment of the incubation period, which is the period between the infection and the illness onset, is essential to identify the sufficient isolation period for infectious diseases. In South Korea, a few cases of the coronavirus disease 2019 (COVID-19) were identified after the 14-day self-quarantine program, and the length of this quarantine has raised controversial issues for the Korean public health professionals. We estimated the COVID-19 incubation period using the log-normal distribution from publicly available data. The data were obtained from the press release of the Busan city department of public health and news reports. We collected and analysed information for 47 patients with a median age of 30. We estimated that the median incubation period was three days (95% Confidence Interval, 0.6-8.2). We also did not find any significant difference in the incubation period between males and females. Our findings indicate that a 14-day self-quarantine program should be sufficient to prevent spreading in the infection of suspected individuals with COVID-19 in the community.


Asunto(s)
Infecciones por Coronavirus , Periodo de Incubación de Enfermedades Infecciosas , Pandemias , Neumonía Viral , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19 , Femenino , Humanos , Masculino , Persona de Mediana Edad , República de Corea , Adulto Joven
12.
Fish Physiol Biochem ; 45(3): 873-883, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30387033

RESUMEN

n-Butyl acrylate (nBA) is one of acrylate esters which has been applied to diverse industrial fields. For unveiling of xeno-estrogenic effects and oxidative stress induction by nBA under two-generational exposure regimen (17 weeks), the biomarkers relevant to an estrogenic effect and oxidative stress were analyzed. Acute toxicity value of nBA in Oryzias latipes was 7.2 mg/L (96 h-LC50). Over exposure time, the significant transcriptional change of cytochrome P450 19A (CYP19A) and vitellogenin 1/2 (VTG1/2) was not observed (one-way ANOVA, P < 0.05), meaning no estrogenic effect of nBA. Significant reduction of glutathione (GSH) content was observed in F0 male and female fish, while in F1 male, the content was increased (P < 0.05). Catalase (CAT) activity of male fish showed the significant decrease in both F0 and F1 fish, showing multi-generational suppressing effect of nBA on CAT activity. But in case of reactive oxygen species (ROS), expression level and glutathione S-transferase (GST) activity were not modulated in response to nBA. These findings suggest that nBA could affect an antioxidant system alteration through GSH depletion and inhibition of CAT activity which could be transferred to the next generation, whereas xeno-estrogenic effect would be questionable.


Asunto(s)
Acrilatos/toxicidad , Antioxidantes/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Oryzias/genética , Acrilatos/metabolismo , Adaptación Fisiológica/fisiología , Animales , Femenino , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Hígado/metabolismo , Masculino , Oryzias/metabolismo , Pruebas de Toxicidad Aguda
13.
Opt Express ; 26(2): 1324-1332, 2018 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-29402007

RESUMEN

We demonstrate the use of the ultrafast spatial coherent-control method to resolve the fine-structure two-photon transitions of atomic rubidium. Counter-propagating ultrafast optical pulses with spectral phase and amplitude programmed with our optimized solutions successfully induced the two-photon transitions through 5S1/2-5P1/2-5D and 5S1/2-5P3/2-5D pathways, both simultaneously and at distinct spatial locations. Three different pulse-shaping solutions are introduced that combine amplitude shaping, which avoids direct intermediate resonances, and phase programming, which enables the remaining spectral components to be coherently interfered through the targeted transition pathways. Experiments were performed with a room-temperature vapor cell, and the results agree well with theoretical analysis.

14.
Phys Rev Lett ; 120(18): 180502, 2018 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-29775353

RESUMEN

Dynamics of large complex systems, such as relaxation towards equilibrium in classical statistical mechanics, often obeys a master equation that captures essential information from the complexities. Here, we find that thermalization of an isolated many-body quantum state can be described by a master equation. We observe sudden quench dynamics of quantum Ising-like models implemented in our quantum simulator, defect-free single-atom tweezers in conjunction with Rydberg-atom interaction. Saturation of their local observables, a thermalization signature, obeys a master equation experimentally constructed by monitoring the occupation probabilities of prequench states and imposing the principle of the detailed balance. Our experiment agrees with theories and demonstrates the detailed balance in a thermalization dynamics that does not require coupling to baths or postulated randomness.

15.
Langmuir ; 34(15): 4634-4639, 2018 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-29597351

RESUMEN

By selective attachment of fluorescent dyes to the core-forming block, we produced patchy micelles of diblock copolymers with fluorophores localized in the micellar cores. From these patchy micelles functionalized with dyes, fluorescent supracolloidal chains in a few micrometers were polymerized by combining the patches in neighboring micelles, indicating that selective modification of the core-forming block delivered the functionality into the supracolloidal chain without altering the polymerization of patchy micelles. Thus, with the same polymerization condition, we were able to produce red-, green-, and blue-emitting supracolloidal chains by varying the fluorescent dyes attached to the core-forming block. In addition, we directly visualized individual supracolloidal chains by fluorescence confocal microscopy as well as by transmission electron microscopy.

16.
J Chem Phys ; 148(13): 134310, 2018 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-29626901

RESUMEN

Hydrazinium azide (HA) has been investigated at high pressures to 68 GPa using confocal micro-Raman spectroscopy and synchrotron powder x-ray diffraction. The results show that HA undergoes structural phase transitions from solid HA-I to HA-II at 13 GPa, associated with the strengthening of hydrogen bonding, and then to N8 at 40 GPa. The transformation of HA to recently predicted N8 (N≡N+-N--N=N--N-+N≡N) is evident by the emergence of new peaks at 2384 cm-1, 1665 cm-1, and 1165 cm-1, arising from the terminal N≡N stretching, the central N=N stretching, and the N-N stretching, respectively. However, upon decompression, N8 decomposes to ε-N2 below 25 GPa, but the remnant can be seen as low as 3 GPa.

17.
Soft Matter ; 13(38): 6756-6760, 2017 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-28937168

RESUMEN

Supracolloidal chains of diblock copolymer micelles were functionalized with gold and silver nanoparticles (NPs). Both NPs were independently synthesized in situ in the core of spherical micelles which were then converted to patchy micelles. With these patchy micelles as colloidal monomers, supracolloidal chains were polymerized by combining the patches of neighboring micelles. Since all micelles contained NPs, NPs were incorporated in every repeat unit of chains. In addition, a single gold NP was synthesized in the micellar core in contrast to several silver NPs so that we differentiated the chains with Au NPs from those with Ag NPs by the number of NPs in the repeat unit as well as by plasmonic bands in UV-Vis spectra.

18.
Angew Chem Int Ed Engl ; 56(5): 1278-1282, 2017 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-28000315

RESUMEN

p53 is an important tumor-suppressor protein deactivation of which by mdm2 results in cancers. A SUMO-specific protease 4 (SUSP4) was shown to rescue p53 from mdm2-mediated deactivation, but the mechanism is unknown. The discovery by NMR spectroscopy of a "p53 rescue motif" in SUSP4 that disrupts p53-mdm2 binding is presented. This 29-residue motif is pre-populated with two transient helices connected by a hydrophobic linker. The helix at the C-terminus binds to the well-known p53-binding pocket in mdm2 whereas the N-terminal helix serves as an affinity enhancer. The hydrophobic linker binds to a previously unidentified hydrophobic crevice in mdm2. Overall, SUSP4 appears to use two synergizing modules, the p53 rescue motif described here and a globular-structured SUMO-binding catalytic domain, to stabilize p53. A p53 rescue motif peptide exhibits an anti-tumor activity in cancer cell lines expressing wild-type p53. A pre-structures motif in the intrinsically disordered proteins is thus important for target recognition.


Asunto(s)
Cisteína Endopeptidasas/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Secuencia de Aminoácidos , Sitios de Unión , Dominio Catalítico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cisteína Endopeptidasas/química , Humanos , Simulación de Dinámica Molecular , Mutagénesis , Péptidos/farmacología , Unión Proteica , Proteínas Proto-Oncogénicas c-mdm2/química , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteína p53 Supresora de Tumor/química , Proteína p53 Supresora de Tumor/genética
19.
Gut ; 65(1): 19-32, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25410163

RESUMEN

BACKGROUND: Worldwide, gastric cancer (GC) is the fourth most common malignancy and the most common cancer in East Asia. Development of targeted therapies for this disease has focused on a few known oncogenes but has had limited effects. OBJECTIVE: To determine oncogenic mechanisms and novel therapeutic targets specific for GC by identifying commonly dysregulated genes from the tumours of both Asian-Pacific and Caucasian patients. METHODS: We generated transcriptomic profiles of 22 Caucasian GC tumours and their matched non-cancerous samples and performed an integrative analysis across different GC gene expression datasets. We examined the inhibition of commonly overexpressed oncogenes and their constituent signalling pathways by RNAi and/or pharmacological inhibition. RESULTS: Hepatocyte nuclear factor-4α (HNF4α) upregulation was a key signalling event in gastric tumours from both Caucasian and Asian patients, and HNF4α antagonism was antineoplastic. Perturbation experiments in GC tumour cell lines and xenograft models further demonstrated that HNF4α is downregulated by AMPKα signalling and the AMPK agonist metformin; blockade of HNF4α activity resulted in cyclin downregulation, cell cycle arrest and tumour growth inhibition. HNF4α also regulated WNT signalling through its target gene WNT5A, a potential prognostic marker of diffuse type gastric tumours. CONCLUSIONS: Our results indicate that HNF4α is a targetable oncoprotein in GC, is regulated by AMPK signalling through AMPKα and resides upstream of WNT signalling. HNF4α may regulate 'metabolic switch' characteristic of a general malignant phenotype and its target WNT5A has potential prognostic values. The AMPKα-HNF4α-WNT5A signalling cascade represents a potentially targetable pathway for drug development.


Asunto(s)
Proteínas Quinasas Activadas por AMP/genética , Adenocarcinoma/genética , Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión Génica , Factor Nuclear 4 del Hepatocito/genética , Proteínas Proto-Oncogénicas/genética , Neoplasias Gástricas/genética , Proteínas Wnt/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Adenocarcinoma/etnología , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Animales , Pueblo Asiatico , Biomarcadores de Tumor/metabolismo , Western Blotting , Estudios de Casos y Controles , Línea Celular Tumoral , Regulación hacia Abajo , Femenino , Factor Nuclear 4 del Hepatocito/metabolismo , Humanos , Inmunohistoquímica , Ratones , Ratones Endogámicos BALB C , Trasplante de Neoplasias , Proteínas Proto-Oncogénicas/metabolismo , Distribución Aleatoria , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Gástricas/etnología , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Regulación hacia Arriba , Población Blanca , Proteínas Wnt/metabolismo , Vía de Señalización Wnt , Proteína Wnt-5a
20.
Ecotoxicol Environ Saf ; 126: 147-153, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26748376

RESUMEN

The root elongation bioassay is one of the most straightforward test methods used for environmental monitoring in terms of simplicity, rapidity and economy since it merely requires filter paper, distilled water and Petri dishes. However, filter paper as a support material is known to be problematic as it can reduce the sensitivity of the test. The newly developed hydroponic method reported here differs from the conventional root elongation method (US EPA filter paper method) in that no support material is used and the exposure time is shorter (48 h in this test versus 120 h in the US EPA test). For metals, the hydroponic test method was 3.3 (for Hg) to 57 (for Cu) times more sensitive than the US EPA method with the rank orders of sensitivity, estimated from EC50 values, being Cu≥Cd>Ni≥Zn≥Hg for the former and Hg≥Cu≥Ni≥Cd≥Zn for the latter methods. For phenol, the results did not differ significantly; EC50 values were 124 mg L(-1) and 108-180 mg L(-1) for the hydroponic and filter paper methods, respectively. Lettuce was less sensitive than daphnids to wastewaters, but the root elongation response appears to be wastewater-specific and is especially sensitive for detecting the presence of fluorine. The new hydroponic test thus provides many practical advantages, especially in terms of cost and time-effectiveness requiring only a well plate, a small volume of distilled water and short exposure period; furthermore, no specialist expertise is required. The method is simpler than the conventional EPA technique in not using filter paper which can influence the sensitivity of the test. Additionally, plant seeds have a long shelf-life and require little or no maintenance.


Asunto(s)
Monitoreo del Ambiente/métodos , Hidroponía/métodos , Lactuca/efectos de los fármacos , Metales Pesados/toxicidad , Fenol/toxicidad , Raíces de Plantas/efectos de los fármacos , Aguas Residuales/toxicidad , Contaminantes Químicos del Agua/toxicidad , Bioensayo/métodos , Lactuca/crecimiento & desarrollo , Raíces de Plantas/crecimiento & desarrollo , Semillas/efectos de los fármacos , Semillas/crecimiento & desarrollo , Pruebas de Toxicidad/métodos
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