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1.
Commun Biol ; 6(1): 630, 2023 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-37301948

RESUMO

Coral reefs in the Central Indo-Pacific region comprise some of the most diverse and yet threatened marine habitats. While reef monitoring has grown throughout the region in recent years, studies of coral reef benthic cover remain limited in spatial and temporal scales. Here, we analysed 24,365 reef surveys performed over 37 years at 1972 sites throughout East Asia by the Global Coral Reef Monitoring Network using Bayesian approaches. Our results show that overall coral cover at surveyed reefs has not declined as suggested in previous studies and compared to reef regions like the Caribbean. Concurrently, macroalgal cover has not increased, with no indications of phase shifts from coral to macroalgal dominance on reefs. Yet, models incorporating socio-economic and environmental variables reveal negative associations of coral cover with coastal urbanisation and sea surface temperature. The diversity of reef assemblages may have mitigated cover declines thus far, but climate change could threaten reef resilience. We recommend prioritisation of regionally coordinated, locally collaborative long-term studies for better contextualisation of monitoring data and analyses, which are essential for achieving reef conservation goals.


Assuntos
Antozoários , Recifes de Corais , Animais , Teorema de Bayes , Oceanos e Mares
2.
Sci Rep ; 10(1): 18012, 2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33093480

RESUMO

We have successfully grown centimeter-sized layered [Formula: see text] single crystals under high oxygen pressures of 120-150 bar by the floating zone technique. This enabled us to perform neutron scattering experiments where we observe close to quarter-integer magnetic peaks below [Formula: see text] that are accompanied by steep upwards dispersing spin excitations. Within the high-frequency Ni-O bond stretching phonon dispersion, a softening at the propagation vector for a checkerboard modulation can be observed. We were able to simulate the magnetic excitation spectra using a model that includes two essential ingredients, namely checkerboard charge disproportionation and nano phase separation. The results thus suggest that charge disproportionation is preferred instead of a Jahn-Teller distortion even for this layered [Formula: see text] system.

3.
Phys Rev Lett ; 124(9): 091101, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32202874

RESUMO

We report the observation of radar echoes from the ionization trails of high-energy particle cascades. Data were taken at the SLAC National Accelerator Laboratory, where the full electron beam (∼10^{9} e^{-} at ∼10 GeV/e^{-}) was directed into a plastic target to simulate an ultrahigh-energy neutrino interaction. The target was interrogated with radio waves, and coherent radio reflections from the cascades were detected with properties consistent with theoretical expectations. This is the first definitive observation of radar echoes from high-energy particle cascades, which may lead to a viable neutrino detection technology for energies ≳10^{16} eV.

4.
J Eur Acad Dermatol Venereol ; 34(8): 1722-1729, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31919907

RESUMO

BACKGROUND: Vitamin D has antineoplastic effects, but the synthesis of vitamin D requires ultraviolet radiation, a known risk factor for melanoma. OBJECTIVE: To investigate the correlations between serum vitamin D levels and risk and prognosis of melanoma. METHODS: A systematic review and meta-analysis were conducted. Online databases were searched on 31 Oct 2018. RESULTS: Twenty-five studies with a total of 11166 patients with melanoma were included. There was no significant difference in serum vitamin D levels between patients with melanoma and controls [standardized mean difference (SMD), -0.185; 95% confidence interval (CI), -0.533 to 0.162]. However, the prevalence of vitamin D deficiency was significantly higher in patients with melanoma than that in controls (odds ratio, 2.115; 95% CI, 1.151-3.885). In terms of prognosis, serum vitamin D levels were significantly higher in melanoma patients with lower Breslow thickness (≦1 vs. >1 mm: SMD, 0.243; 95% CI, 0.160-0.327). Moreover, melanoma patients with lower vitamin D levels had a significantly higher mortality rate (hazard ratio, 1.558; 95% CI, 1.258-1.931). CONCLUSIONS: Vitamin D deficiency is associated with higher Breslow thickness and mortality in melanoma patients.


Assuntos
Melanoma , Deficiência de Vitamina D , Humanos , Melanoma/epidemiologia , Prognóstico , Raios Ultravioleta , Vitamina D , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia
5.
Climacteric ; 23(2): 130-139, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31612733

RESUMO

Background: Acupuncture has been used for many breast cancer treatment-related problems, but how long the effect lasts is unknown. This meta-analysis aims to evaluate how long the effect of acupuncture on breast cancer-related hot flushes and menopause symptoms lasts.Methods: The research design followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement, without language restrictions. Seven databases from inception through February 2019 were accessed; only randomized clinical trials (RCTs) that examined the maintenance effect of acupuncture on hot flushes or menopause symptoms after treatment were included. Cochrane criteria were followed and RevMan 5.2 software was used to analyze trials.Results: In total, 943 patients from 13 RCTs were analyzed. The meta-analysis showed that acupuncture had no significant long-term maintenance effect on the frequency or severity of hot flushes (p = 0.29; p = 0.34), but had a significant 3-month maintenance effect of ameliorating menopause symptoms at 3 months after treatment ended (p = 0.001). No adverse events were reported.Conclusions: Acupuncture significantly alleviated menopause symptoms for at least 3 months, but not hot flushes. Breast cancer patients concerned about the adverse effects of hormone therapy could consider acupuncture as an alternative. Additional acupuncture at 3 months after the initial treatment course could be considered. A large-scale study may help to define the optimal guideline for this issue.


Assuntos
Terapia por Acupuntura , Neoplasias da Mama/terapia , Fogachos/terapia , Menopausa/fisiologia , Neoplasias da Mama/complicações , Feminino , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Sensors (Basel) ; 19(7)2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30965566

RESUMO

Lane keeping systems for a keeping a vehicle in the desired lane is key to advanced driving assistance system in autonomous vehicles. This paper presents a cost-effective image sensor with efficient processing algorithm for lane detection and lane control applications to autonomous delivery systems. The algorithm includes (1) lane detection by inverse perspective mapping and random sample consensus parabola fitting and (2) lane control by pure pursuit steering controller and classical proportional integral speed controller based on a nonholonomic kinematic model. The image sensor experiments conducted on a 1/10 scale model car maneuvering in a straight⁻curve⁻straight lane validate the better processing performance before, during, and after the turning section over previous work. The image sensor with the processing algorithm achieves the average lane detection error within 5% and maximum cross-track error within 9% in real-time. The development shall pave the way to cost-effective autonomous delivery systems.

7.
Integr Comp Biol ; 59(1): 182-192, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31004492

RESUMO

In this study we developed an analytical relationship between adhesive digit orientation and adhesive force capacity to describe the tendencies of climbing organisms that use adhesion for climbing to align their toes in the direction of loading, maximizing adhesive force capacity. We fabricated a multi-component adhesive device with multiple contact surfaces, or digits, to act as a model system mimicking the angular motion of a foot and found the synthetic experiments agree with the developed analytical relationship. In turn, we find that observations of gekkonid lizards climbing on vertical substrates correlate well with our analytical relationship; a reduction in toe spacing is seen on the forelimbs when the animals are facing up. Interestingly, the toes on the hindlimbs tend to have an increase in spacing, possibly a mechanism for stabilization rather than load-bearing.


Assuntos
Lagartos/fisiologia , Locomoção , Dedos do Pé/fisiologia , Adesividade , Animais , Fenômenos Biomecânicos , Lagartos/anatomia & histologia , Dedos do Pé/anatomia & histologia
8.
Water Sci Technol ; 79(2): 349-355, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30865606

RESUMO

The effects of salinity on the photodegradation and mineralization of sulfonamides in the UV/TiO2 system were investigated. The goals of this study were to analyze the effects of pH and salinity on the sulfonamide concentration and total organic carbon (TOC) during the removal of sulfonamides in a UV/TiO2 system. Four sulfonamides - sulfadiazine (SDZ), sulfamethizole (SFZ), sulfamethoxazole (SMX) and sulfathiazole (STZ) - were selected as parent compounds. The photodegradation and mineralization rates of sulfonamides in the UV/TiO2 system satisfy pseudo-first-order kinetics. Direct photolysis degraded sulfonamides but sulfonamides cannot be mineralized. The photodegradation and mineralization rate constants in all experiments followed the order pH 5 > pH 7 > pH 9. At pH 5, the mineralization rate constants of SMX, SFZ, SDZ and STZ were 0.015, 0.009, 0.012 and 0.011 min-1, respectively. The addition of NaCl inhibited the mineralization of the four tested sulfonamides more than it inhibited their photodegradation. The inhibitory effect of chloride ions on the removal of sulfonamides in the UV/TiO2 system was attributed to the scavenging by chloride ions of hydroxyl radicals (HO•) and holes and the much lower reactivity of chlorine radicals thus formed, even though the chlorine radicals were more abundant than HO•.


Assuntos
Sulfonamidas/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Cinética , Fotólise , Salinidade , Sulfonamidas/análise , Titânio , Raios Ultravioleta , Poluentes Químicos da Água/análise
9.
Nat Commun ; 9(1): 43, 2018 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-29298977

RESUMO

The material class of rare earth nickelates with high Ni3+ oxidation state is generating continued interest due to the occurrence of a metal-insulator transition with charge order and the appearance of non-collinear magnetic phases within this insulating regime. The recent theoretical prediction for superconductivity in LaNiO3 thin films has also triggered intensive research efforts. LaNiO3 seems to be the only rare earth nickelate that stays metallic and paramagnetic down to lowest temperatures. So far, centimeter-sized impurity-free single crystal growth has not been reported for the rare earth nickelates material class since elevated oxygen pressures are required for their synthesis. Here, we report on the successful growth of centimeter-sized LaNiO3 single crystals by the floating zone technique at oxygen pressures of up to 150 bar. Our crystals are essentially free from Ni2+ impurities and exhibit metallic properties together with an unexpected but clear antiferromagnetic transition.

10.
Clin Microbiol Infect ; 23(2): 110-116, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27851998

RESUMO

OBJECTIVES: We studied paediatric patients with human adenovirus (HAdV) infection during the 2011 outbreak in northern Taiwan to define the clinical features of different HAdV genotypes in children. METHODS: Between January and December 2011, 637 patients <19 years of age exhibited culture-confirmed adenoviral infection in Chang Gung Memorial Hospital, and provided specimens available for genotyping by multiplex real-time PCR. Clinical data were collected retrospectively. RESULTS: Excluding five cases with multiple genotypes, 632 cases were included for analysis. Three genotypes were identified, including HAdV-3 (429/632; 67.6%), HAdV-7 (144/632; 22.6%) and HAdV-2 (59/632; 9.8%). Median age was 4.58 years (range 2 months to 18 years), with children infected with HAdV-3 significantly older (82.9% >3 years; p <0.001). Of the 621 inpatients, 98.2% had fevers and all exhibited respiratory symptoms, 75 patients (12.1%) had lower respiratory tract infections, 20 (3.2%) required intensive care (HAdV-2: 1; HAdV-3: 8; and HAdV-7: 11), and three died (all HAdV-7-infected). HAdV-3-infected patients were significantly more likely to have upper respiratory symptoms and a high serum C-reactive protein level >100 mg/L, whereas leucocytosis (white blood cell count >15 000/mm3) was more common in HAdV-2-infected patients (p 0.007). HAdV-7 infections were significantly associated with a longer duration of fever, leucopenia (white blood cell count <5000/mm3), thrombocytopenia (platelet count <150 000/mm3), lower respiratory tract infections, a longer length of hospital stay, and requiring intensive care (all p <0.001). CONCLUSION: Childhood HAdV-2, HAdV-3 and HAdV-7 infections may exhibit different clinical manifestations. Although HAdV-3 was the most prevalent genotype observed during the 2011 Taiwan outbreak, HAdV-7 caused more severe disease characteristics and outcomes.


Assuntos
Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/classificação , Adenovírus Humanos/genética , Genótipo , Infecções por Adenovirus Humanos/diagnóstico , Infecções por Adenovirus Humanos/história , Adolescente , Proteínas do Capsídeo/genética , Criança , Pré-Escolar , Comorbidade , Surtos de Doenças , Feminino , História do Século XXI , Humanos , Lactente , Unidades de Terapia Intensiva Pediátrica , Tempo de Internação , Masculino , Filogenia , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/história , Infecções Respiratórias/virologia , Estudos Retrospectivos , Taiwan/epidemiologia
11.
Nat Commun ; 7: 12712, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27581797

RESUMO

The strong coupling between antiferromagnetism and ferroelectricity at room temperature found in BiFeO3 generates high expectations for the design and development of technological devices with novel functionalities. However, the multi-domain nature of the material tends to nullify the properties of interest and complicates the thorough understanding of the mechanisms that are responsible for those properties. Here we report the realization of a BiFeO3 material in thin film form with single-domain behaviour in both its magnetism and ferroelectricity: the entire film shows its antiferromagnetic axis aligned along the crystallographic b axis and its ferroelectric polarization along the c axis. With this we are able to reveal that the canted ferromagnetic moment due to the Dzyaloshinskii-Moriya interaction is parallel to the a axis. Furthermore, by fabricating a Co/BiFeO3 heterostructure, we demonstrate that the ferromagnetic moment of the Co film does couple directly to the canted moment of BiFeO3.

12.
Sci Rep ; 6: 25117, 2016 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-27117928

RESUMO

We observe quasi-static incommensurate magnetic peaks in neutron scattering experiments on layered cobalt oxides La2-xSrxCoO4 with high Co oxidation states that have been reported to be paramagnetic. This enables us to measure the magnetic excitations in this highly hole-doped incommensurate regime and compare our results with those found in the low-doped incommensurate regime that exhibit hourglass magnetic spectra. The hourglass shape of magnetic excitations completely disappears given a high Sr doping. Moreover, broad low-energy excitations are found, which are not centered at the incommensurate magnetic peak positions but around the quarter-integer values that are typically exhibited by excitations in the checkerboard charge ordered phase. Our findings suggest that the strong inter-site exchange interactions in the undoped islands are critical for the emergence of hourglass spectra in the incommensurate magnetic phases of La2-xSrxCoO4.

13.
Cell Death Dis ; 6: e1642, 2015 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-25675302

RESUMO

Human Lon protease is a mitochondrial matrix protein with several functions, including protein degradation, mitochondrial DNA (mtDNA) binding, and chaperone activity. Lon is currently emerging as an important regulator of mitochondria-contributed tumorigenesis due to its overexpression in cancer cells. To understand the mechanism of increased Lon in tumor cells, we studied the interactome to identify the chaperone Lon-associated proteins by proteomics approaches using the cells overexpressing Lon. In the present study, we designed a method connecting co-immunoprecipitation (Co-IP) to in-solution digestion for the shotgun mass spectrometry. We identified 76 proteins that were putative Lon-associated proteins that participated in mitochondrial chaperone system, cellular metabolism and energy, cell death and survival, and mtDNA stability. The association between Lon and NDUFS8 or Hsp60-mtHsp70 complex was confirmed by Co-IP and immunofluorescence co-localization assay. We then found that the protein stability/level of Hsp60-mtHsp70 complex depends on the level of Lon under oxidative stress. Most importantly, the ability of increased Lon-inhibited apoptosis is dependent on Hsp60 that binds p53 to inhibit apoptosis. These results suggest that the mechanism underlying cell survival regulated by Lon is mediated by the maintenance of the protein stability of Hsp60-mtHsp70 complex. This new knowledge of chaperone Lon interactome will allow us to better understand the cellular mechanism of Lon in mitochondrial function and of its overexpression in enhancing cell survival and tumorigenesis.


Assuntos
Chaperonina 60/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Mitocôndrias/enzimologia , Protease La/metabolismo , Apoptose , Western Blotting , Linhagem Celular , Sobrevivência Celular/genética , Sobrevivência Celular/fisiologia , Biologia Computacional , Humanos , Imunoprecipitação , Ligação Proteica , Espectrometria de Massas em Tandem
14.
Phys Rev Lett ; 113(21): 217203, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25479519

RESUMO

SmFeO3 has attracted considerable attention very recently due to its reported multiferroic properties above room temperature. We have performed powder and single crystal neutron diffraction as well as complementary polarization dependent soft X-ray absorption spectroscopy measurements on floating-zone grown SmFeO3 single crystals in order to determine its magnetic structure. We found a k=0 G-type collinear antiferromagnetic structure that is not compatible with inverse Dzyaloshinskii-Moriya interaction driven ferroelectricity. While the structural data reveal a clear sign for magneto-elastic coupling at the Néel-temperature of ∼675 K, the dielectric measurements remain silent as far as ferroelectricity is concerned.

15.
Water Sci Technol ; 70(8): 1428-33, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25353950

RESUMO

This study produced immobilized Cu2O via microwave irradiation. The surface properties of Cu2O were assessed by X-ray diffraction, scanning electron microscopy, and UV-vis spectroscopy. The catalytic activity of the generated Cu2O was examined for bisphenol (BPA) degradation in Cu2O/H2O2 and visible-light/Cu2O/H2O2 systems under various H2O2 concentrations. Cu2O can decompose H2O2 to generate radicals, similar to the Fenton-like process. The BPA degradation rate followed pseudo-first-order kinetics. The optimal H2O2 concentration was 30 mM and the BPA degradation rate under 30 mM H2O2 in the Cu2O/H2O2 and visible-light/Cu2O/H2O2 systems was 1.43 and 2.69 h(-1), respectively. The original Cu2O partly oxidized into CuO in the visible-light/Cu2O/H2O2 system and the BPA degradation percentage declined to 51% from 100% after the fifth cycle.


Assuntos
Compostos Benzidrílicos/química , Cobre/efeitos da radiação , Peróxido de Hidrogênio/química , Luz , Micro-Ondas , Fenóis/química , Poluentes Químicos da Água/química , Cobre/química , Microscopia Eletrônica de Varredura , Espectrofotometria Ultravioleta , Purificação da Água/métodos , Difração de Raios X
16.
Cell Death Dis ; 4: e681, 2013 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-23788038

RESUMO

Lon protease is a multifunction protein and operates in protein quality control and stress response pathways in mitochondria. Human Lon is upregulated under oxidative and hypoxic stresses that represent the stress phenotypes of cancer. However, little literature undertakes comprehensive and detailed investigations on the tumorigenic role of Lon. Overexpression of Lon promotes cell proliferation, apoptotic resistance to stresses, and transformation. Furthermore, Lon overexpression induces the production of mitochondrial reactive oxygen species (ROS) that result from Lon-mediated upregulation of NDUFS8, a mitochondrial Fe-S protein in complex I of electron transport chain. Increased level of mitochondrial ROS promotes cell proliferation, cell survival, cell migration, and epithelial-mesenchymal transition through mitogen-activated protein kinase (MAPK) and Ras-ERK activation. Overall, the present report for the first time demonstrates the role of Lon overexpression in tumorigenesis. Lon overexpression gives an apoptotic resistance to stresses and induces mitochondrial ROS production through Complex I as signaling molecules to activate Ras and MAPK signaling, giving the survival advantages and adaptation to cancer cells. Finally, in silico and immunohistochemistry analysis showed that Lon is overexpressed specifically in various types of cancer tissue including oral cancer.


Assuntos
Carcinogênese/metabolismo , Mitocôndrias/enzimologia , NADH Desidrogenase/metabolismo , Protease La/metabolismo , Superóxidos/metabolismo , Carcinoma de Células Escamosas/enzimologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Estabilidade Enzimática , Transição Epitelial-Mesenquimal , Expressão Gênica , Células HEK293 , Humanos , Sistema de Sinalização das MAP Quinases , Neoplasias Bucais/enzimologia , Fenótipo , Protease La/genética , Regulação para Cima
17.
J Hosp Infect ; 83(4): 288-93, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23399482

RESUMO

BACKGROUND: Human enterovirus 71 (HEV71) infections are a significant public health threat in the Asia-Pacific region and occasionally cause severe neurological complications and even death in children. Although good hand hygiene is important for controlling infection, relevant data regarding the efficacy of widely used hand disinfectants against HEV71 are still lacking. AIM: To investigate the virucidal activity of alcohols and alcohol-based hand disinfectants against HEV71. METHODS: A common alcohol-based hand disinfectant (0.5% chlorhexidine gluconate + 70% isopropanol) as well as different concentrations of isopropanol and ethanol were tested for virucidal activity against HEV71 using the suspension and the fingerpad tests. FINDINGS: In suspension tests, 85% and 95% ethanol achieved a mean log10 reduction factor in HEV71 titre of >3 and nearly 6, respectively, within 10 min. By contrast, 70% and 75% ethanol and any concentration of isopropanol (70-95%) produced a factor of <1 in this test after the same exposure time. In fingerpad tests, only 95% ethanol showed a mean log10 reduction factor of >4, while both 75% ethanol and a chlorhexidine gluconate-containing formula were ineffective against HEV71 with a mean log10 reduction factor of <1 after a 30 s exposure time. CONCLUSIONS: Widely used alcohol-based hand disinfectants based on 70% ethanol or isopropanol have poor effectiveness against HEV71. Ninety-five percent ethanol is the most effective concentration, but still cannot fully inactivate HEV71 and may be impractical for use in many instances. Hand hygiene with alcohol-based hand disinfectants alone is not recommended for preventing HEV71 transmission.


Assuntos
2-Propanol/farmacologia , Antivirais/farmacologia , Desinfetantes/farmacologia , Enterovirus Humano A/efeitos dos fármacos , Etanol/farmacologia , Clorexidina/análogos & derivados , Clorexidina/farmacologia , Viabilidade Microbiana/efeitos dos fármacos
18.
Water Sci Technol ; 65(11): 1970-4, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22592466

RESUMO

This study applies photo-Fenton and photo-Fenton-like systems to decolorize C.I. Reactive Red 2 (RR2). The oxidants were H(2)O(2) and Na(2)S(2)O(8); Fe(2+), Fe(3+), and Co(2+) were used to activate these two oxidants. The effects of oxidant concentration (0.3-2 mmol/L) and temperature (25-55 °C) on decolorization efficiency of the photo-Fenton and photo-Fenton-like systems were determined. The decolorization rate constants (k) of RR2 in the tested systems are consistent with pseudo-first-order kinetics. The rate constant increased as oxidant concentration and temperature increased. Activation energies of RR2 decolorization in the UV/H(2)O(2)/Fe(2+), UV/H(2)O(2)/Fe(3+), UV/Na(2)S(2)O(8)/Fe(2+) and UV/Na(2)S(2)O(8)/Fe(3+) systems were 32.20, 39.54, 35.54, and 51.75 kJ/mol, respectively.


Assuntos
Peróxido de Hidrogênio/química , Ferro/química , Naftalenossulfonatos/química , Oxidantes/química , Triazinas/química , Temperatura , Raios Ultravioleta , Poluentes Químicos da Água/química , Purificação da Água/métodos
19.
Water Sci Technol ; 65(3): 490-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22258680

RESUMO

In this study, C.I. Reactive Red 2 (RR2) was removed from aqueous solutions by chitin. Exactly how the RR2 concentration, chitin dosage, pH, and temperature affected adsorption of RR2 by chitin was then determined. After reaction for 120 min, the amount of 10 and 20 mg/L RR2 absorbed onto chitin was 5.7 and 7.5 mg/g, respectively. The adsorption percentage increased from 56 to 94% when the chitin dosage was increased from 1.5 to 2.5 g/L. Experimental results indicated that the pseudo-second-order model best represents adsorption kinetics. Adsorption of RR2 increased as the temperature increased; however, it decreased with an increased pH. Experimental results further demonstrated that the Freundlich model is superior to the Langmuir model in fitting experimental isotherms. The ΔH° and ΔS° were 16.34 kJ/mol and 152.10 J/mol K, respectively. ΔH° suggested that adsorption of RR2 onto chitin was via physisorption.


Assuntos
Quitina/química , Corantes/química , Naftalenossulfonatos/química , Termodinâmica , Triazinas/química , Água/química , Cinética , Poluentes Químicos da Água
20.
Oncogenesis ; 1: e4, 2012 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-23552556

RESUMO

Nucleophosmin (NPM) is a nucleolar phosphoprotein that is involved in many cellular processes and has both oncogenic and growth suppressing activities. NPM is localized primarily in nucleoli but shuttles between the nucleus and the cytoplasm, and sustained cytoplasmic distribution contributes to its tumor promoting activities. Plakoglobin (PG, γ-catenin) is a homolog of ß-catenin with dual adhesive and signaling functions. These proteins interact with cadherins and mediate adhesion, while their signaling activities are regulated by association with various intracellular partners. Despite these similarities, ß-catenin has a well-defined oncogenic activity, whereas PG acts as a tumor/metastasis suppressor through unknown mechanisms. Comparison of the proteomic profiles of carcinoma cell lines with low- or no PG expression with their PG-expressing transfectants has identified NPM as being upregulated upon PG expression. Here, we examined NPM subcellular distribution and in vitro tumorigenesis/metastasis in the highly invasive and very low PG expressing MDA-MB-231 (MDA-231) breast cancer cells and their transfectants expressing increased PG (MDA-231-PG) or NPM shRNA (MDA-231-NPM-KD) or both (MDA-231-NPM-KD+PG). Increased PG expression increased the levels of nucleolar NPM and coimmunoprecipitation studies showed that NPM interacts with PG. PG expression or NPM knockdown decreased the growth rate of MDA-231 cells substantially and this reduction was decreased further in MDA-231-NPM-KD+PG cells. In in vitro tumorigenesis/metastasis assays, MDA-231-PG cells showed substantially lower and MDA-231-NPM-KD cells substantially higher invasiveness relative to the MDA-231 parental cells, and the co-expression of PG and NPM shRNA led to even further reduction of the invasiveness of MDA-231-PG cells. Furthermore, examination of the levels and localization of PG and NPM in primary biopsies of metastatic infiltrating ductal carcinomas revealed coordinated expression of PG and NPM. Together, the data suggest that PG may regulate NPM subcellular distribution, which may potentially change the function of the NPM protein from oncogenic to tumor suppression.

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