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In this work, we report the synthesis, characterization and biological application of highly stable CdTe/ZnS (cadmium tellurite/zinc sulphide) Core/Shell (CS) quantum dots (QDs) capped with mercaptosuccinic acid (MSA). The CS QDs were synthesized using a simple one-pot aqueous method. The synthesized CdTe/ZnS CS QDs were found to exhibit excellent stability even 100 days after preparation and also showed better photoluminescence quantum yield (PLQY) of about 50% compared with that of only CdTe QDs which was nearly 12%. The formation of the CdTe/ZnS CS was confirmed by high-resolution transmission electron microscopy (HR-TEM), and Fourier transform infra-red (FTIR) and X-ray diffraction (XRD) analyses. Further, on extending our study towards bioimaging of E. coli cells using the QDs samples, we found that CdTe/ZnS CS QDs showed better results compared with CdTe QDs.
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Compostos de Cádmio/química , Escherichia coli/citologia , Medições Luminescentes , Pontos Quânticos , Sulfetos/química , Telúrio/química , Compostos de Zinco/química , Células Cultivadas , Água/químicaRESUMO
INTRODUCTION: C-reactive protein (CRP) is an important non-specific marker of both acute and chronic inflammation and can be elevated in patients with psoriatic arthritis (PsA). However, the use of CRP testing in the management of PsA can vary. This study investigated how CRP testing is implemented in real-world clinical practice for disease management of PsA. METHODS: A point-in-time survey of rheumatologists and dermatologists and their next six consulting patients with PsA was conducted in France, Germany, Italy, Spain, UK (EU5), and the USA between June and August 2018. Use of CRP testing was obtained by asking the physician to state (yes/no) whether CRP was used to aid PsA diagnosis and/or to monitor the patient's disease activity. The number of CRP tests conducted in the last 12 months for each patient enrolled was provided. RESULTS: Data were collected for 2270 patients (USA, n = 595; EU5, n = 1675). In the EU5, CRP testing was conducted to aid diagnosis in 78.7% of patients (vs. 43.4% in USA) and CRP was used to monitor disease activity in 72.0% (vs. 34.6% in USA). The majority (80.9%) of patients in the EU5 had at least one CRP test in the last 12 months compared to 42.9% in the USA. Patients treated by rheumatologists (vs. dermatologists) were at least 50% more likely to have CRP tested for monitoring purposes, this difference being most pronounced in the USA. In the EU5, CRP testing was conducted a mean ± standard deviation of 2.7 ± 1.7 times during the last 12 months, versus 2.0 ± 1.4 in the USA. CONCLUSIONS: CRP was more commonly used for the diagnosis and monitoring of PsA in Europe compared to the USA and was more commonly ordered by rheumatologists than dermatologists. In the absence of a better serum biomarker of inflammation, more data are needed to understand how CRP testing should be used in the diagnosis and management PsA.
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Synchrotron based combined in situ x-ray diffractometry and reflectometry is used to investigate the role of vacancies for the relaxation of residual stress in thin metallic Pt films. From the experimentally determined relative changes of the lattice parameter a and of the film thickness L the modification of vacancy concentration and residual strain was derived as a function of annealing time at 130 °C. The results indicate that relaxation of strain resulting from compressive stress is accompanied by the creation of vacancies at the free film surface. This proves experimentally the postulated dominant role of vacancies for stress relaxation in thin metal films close to room temperature.
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Melatonin (N-acetyl-5-methoxytrptamine) is a pineal secretory product which is involved in the regulation of circadian rhythm and participates in many physiological functions. It also acts as a potent antioxidant and a powerful free radical scavenger. The membrane-associated Na+/K+-ATPase and Na+/H+ exchanger in erythrocytes play an important role in maintaining cytosolic pH, ionic homeostasis, cell osmolarity and in the regulation of transmembrane ion movement. The present work was undertaken to determine the role of melatonin in modulating the activity of Na+/K+-ATPase and Na+/H+ exchanger in human erythrocytes. Our observation shows circadian modulation of Na+/K+-ATPase and Na+/H+ exchanger which may have important therapeutic implications. Exogenous melatonin modulated the activities of Na+/K+-ATPase and Na+/H+ exchanger in human red blood cells, this effect may in part be explained due to the antioxidative effect of melatonin and also due to modulation of membrane fluidity. Further work is needed to understand the mechanism of action.
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Antioxidantes/metabolismo , Eritrócitos/enzimologia , Melatonina/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Adulto , Ritmo Circadiano , Humanos , Adulto JovemRESUMO
OBJECTIVES: To compare healthcare resource utilization and costs among patients with psoriasis, psoriatic arthritis (PsA), and a control group of patients without psoriasis and PsA in the USA. METHODS: The IBM® MarketScan® Commercial Database was used to identify three adult patient groups from 1/1/2009 through 4/30/2020: (1) Psoriasis: ≥ 2 diagnoses ≥ 30 days apart for psoriasis (no PsA diagnoses); (2) PsA: ≥ 2 diagnoses for PsA; (3) Control: no psoriasis or PsA diagnoses in their entire claims records. Patients with comorbid rheumatoid arthritis, ankylosing spondylitis, Crohn's disease, or ulcerative colitis were excluded from the analyses. Controls were matched 1:1 to psoriasis and PsA patients based on age, gender, index year, and number of non-rheumatological comorbidities. Healthcare resource utilization and costs (in 2019 USD) were evaluated descriptively and through mixed models for five years of follow-up. RESULTS: A total of 142,531 psoriasis and 21,428 PsA patients were matched to the control group (N = 163,959). Annual all-cause healthcare costs per patient were $7,470, $11,062, and $29,742 for the control, psoriasis, and PsA groups, respectively. All-cause healthcare costs increased over time and were significantly greater among PsA vs. psoriasis (p < 0.0001) and the control groups (p < 0.0001). Across all categories of healthcare resources, utilization was greatest among patients with PsA and lowest in the control group. CONCLUSION: Annual healthcare costs and resource utilization were significantly higher with PsA compared with psoriasis and the control group, confirming the substantial economic burden of PsA. The cost disparity between these patient groups highlights a continued unmet medical need. Key Points ⢠Patients with PsA incurred significantly greater healthcare resource utilization and costs than patients with psoriasis and patients without psoriasis and PsA. ⢠Significantly greater costs and healthcare resource utilization were also observed among patients with psoriasis compared with patients without psoriasis and PsA.
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Artrite Psoriásica , Psoríase , Adulto , Artrite Psoriásica/terapia , Custos de Cuidados de Saúde , Humanos , Aceitação pelo Paciente de Cuidados de Saúde , Psoríase/terapia , Estudos Retrospectivos , Estados UnidosRESUMO
OBJECTIVES: To compare work absenteeism and short-term disability among adults with psoriasis or psoriatic arthritis (PsA), versus controls in the USA. METHODS: Adults eligible for work absenteeism and/or short-term disability benefits between 1/1/2009 and 4/30/2020 were screened in the IBM® MarketScan® Commercial and Health and Productivity Management Databases. The following groups were defined: (1) psoriasis: ≥ 2 psoriasis diagnoses ≥ 30 days apart and no PsA diagnoses; (2) PsA: ≥ 2 PsA diagnoses ≥ 30 days apart; (3) control: absence of psoriasis and PsA diagnoses. Controls were matched to psoriasis and PsA patients based on age, gender, index year, and comorbidities. Non-recreational work absences and sick leaves were evaluated in absentee-eligible patients, and short-term disability was evaluated in short-term disability-eligible patients. Costs (in 2019 USD) associated with each type of work absence were evaluated. RESULTS: 4261 psoriasis and 616 PsA absentee-eligible and 25,213 psoriasis and 3480 PsA short-term disability-eligible patients were matched to controls. Average non-recreational work absence costs were $1681, $1657, and $1217 for the PsA, psoriasis, and control group, respectively. Compared with psoriasis patients and controls, more PsA patients had sick leaves after 1 year (56.2% versus 55.6% and 41.5%, p < 0.0001). Similarly, short-term disability was more frequent in PsA patients than psoriasis patients and controls at year one (8.8% versus 5.6% and 4.7%, p < 0.0001) and corresponding costs were higher ($605, $406, and $335 on average, p < 0.0001). CONCLUSION: Annual work absenteeism and short-term disability were consistently greater among patients with PsA and psoriasis than controls, highlighting the substantial economic burden of psoriatic disease. Key points ⢠Patients with PsA had greater short-term disability compared with patients with psoriasis and patients with neither psoriasis nor PsA. ⢠Patients with PsA and patients with psoriasis incurred greater non-recreational work absences and sick leaves than patients with neither psoriasis nor PsA.
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Artrite Psoriásica , Psoríase , Absenteísmo , Adulto , Artrite Psoriásica/epidemiologia , Eficiência , Humanos , Psoríase/epidemiologia , Estudos Retrospectivos , Estados UnidosRESUMO
OBJECTIVE: To compare the relative efficacy of intravenous golimumab (GOL IV) and infliximab (IFX) for active ankylosing spondylitis (AS). METHODS: Propensity score (PS) methods were used to compare the efficacy of GOL IV 2 mg/kg and IFX 5 mg/kg using individual patient data (IPD) from the active arms of the phase 3 GO-ALIVE and ASSERT studies. Outcomes included the proportion of patients with a ≥ 20% improvement in the Assessment of Spondyloarthritis International Society Criteria (ASAS20), change from baseline in Bath Ankylosing Spondylitis Functional Index (BASFI) score, and change from baseline in C-reactive protein (CRP) levels from weeks 4-52. RESULTS: Before matching, 105 patients were treated with GOL IV and 201 patients were treated with IFX. After matching on all covariates, 118 patients were included in the ASAS20 analysis, 96 in the BASFI analysis, and 160 in the CRP analysis. After matching, GOL IV showed significantly greater improvement in ASAS20 response than IFX for weeks 28-44 (e.g., OR = 9.05 [95% CI 1.62-50.4] at week 44) and was comparable in change from baseline in BASFI scores and CRP levels to IFX at all time points. Results were robust for inclusion of different sets of covariates in scenario analyses. CONCLUSIONS: This is the first analysis of its kind to leverage clinical trial data to compare two biologics using PS methods in the treatment of active AS. Overall, GOL IV was associated with greater improvement in ASAS20 response than IFX in patients with AS at 28, 36, and 44 weeks of follow-up. Key Points ⢠Although intravenous golimumab (GOL IV) and infliximab (IFX) are the only two IV-based tumor necrosis factor (TNF) inhibitors with demonstrated phase 3 clinical efficacy in patients with ankylosing spondylitis (AS), no study has evaluated their comparative efficacy in a head-to-head trial. ⢠Propensity score matching was used to derive indirect treatment comparisons of GOL IV and IFX for ≥ 20% in the Assessment of Spondyloarthritis International Society Criteria (ASAS20), change in Bath Ankylosing Spondylitis Functional Index (BASFI), and change in C-reactive protein (CRP) using individual patient data from the GO-ALIVE and ASSERT phase 3 trials. ⢠Propensity score matched indirect comparisons showed improved relative efficacy of GOL IV compared to IFX; after matching for up to 16 baseline covariates, GOL IV was associated with significantly greater odds of ASAS20 response at weeks 28, 36, and 44 than IFX as well as equivalent changes from baseline in BASFI and CRP. ⢠This novel application of propensity score matching using data from phase 3 trials, the first analysis of its kind in AS, allowed adjustment for important imbalances in prognostic factors between trials to generate estimates of comparative efficacy between GOL IV and IFX in the absence of a head-to-head trial between these treatments.
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Antirreumáticos , Espondilite Anquilosante , Anticorpos Monoclonais , Antirreumáticos/uso terapêutico , Humanos , Infliximab/uso terapêutico , Pontuação de Propensão , Espondilite Anquilosante/tratamento farmacológico , Resultado do TratamentoRESUMO
OBJECTIVE: To compare the relative efficacy of current and investigational biologic and oral small molecule (OSM) treatments for active ankylosing spondylitis (AS). METHODS: A systematic literature review was conducted to identify all phase 2/3 randomized trials of interest in patients with AS. Outcomes assessed were ≥ 20% improvement in the Assessment of Spondyloarthritis International Society Criteria (ASAS20) and change from baseline in Bath Ankylosing Spondylitis Functional Index (BASFI) and C-reactive protein (CRP) at weeks 12-16. Bayesian network meta-analyses were conducted for outcomes using a random effects model. Baseline-risk adjustment was also conducted to account for differences in placebo response across studies. Surface Under the Cumulative Ranking curve (SUCRA) values are reported, reflecting the relative probability that intervention was the best of all interventions. RESULTS: The investigational agent tofacitinib 5 mg was the top-ranked treatment (SUCRA, 93%) for ASAS20 response, followed by intravenous (IV) golimumab 2 mg/kg (90%). Golimumab IV 2 mg/kg and infliximab 5 mg/kg were the top two ranked treatments for change from baseline in BASFI (golimumab IV, 81%; infliximab, 80%) and change from baseline in CRP (infliximab, 90%; golimumab IV, 82%). CONCLUSIONS: Two approved therapies (golimumab IV, infliximab) and one investigational product ranked highest for efficacy in AS. Key Points ⢠Although golimumab IV, infliximab, and tofacitinib ranked highest for efficacy in AS, differences in efficacy between approved and investigational therapies were not statistically significant.
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Metanálise em Rede , Espondilite Anquilosante/tratamento farmacológico , Terapias em Estudo , Inibidores do Fator de Necrose Tumoral/administração & dosagem , Administração Intravenosa , Anticorpos Monoclonais , Teorema de Bayes , Humanos , Infliximab , Ensaios Clínicos Controlados Aleatórios como Assunto , Inibidores do Fator de Necrose Tumoral/uso terapêuticoRESUMO
In the moment of preparation of this paper, the world is still globally in grip of the Corona (COVID-19) crisis, and the need to understand the broader overall framework of the crisis increases. As in similar cases in the past, also with this one, the main interest is on the "first response". Fully appreciating the efforts of those risking their lives facing pandemics, this paper tries to identify the main elements of the larger, possibly global, framework, supported by international standards, needed to deal with new (emerging) risks resulting from threats like Corona and assess the resilience of systems affected. The paper proposes that future solutions should include a number of new elements, related to both risk and resilience. That should include broadening the scope of attention, currently focused onto preparation and response phases, to the phases of "understanding risks", including emerging risks, and transformation and adaptation. The paper suggests to use resilience indicators in this process. The proposed approach has been applied in different cases involving critical infrastructures in Europe (energy supply, water supply, transportation, etc., exposed to various threats), including the health system in Austria. The detailed, indicator-based, resilience analysis included mapping resilience, resilience stress-testing, visualization, etc., showing, already before the COVID-19, the resilience (stress-testing) limits of the infrastructures. A simpler (57 indicator based) analysis has, then been done for 11 countries (including Austria). The paper links these results with the options available in the area of policies, standards, guidelines and tools (such as the RiskRadar), with focus on interdependencies and global standards-especially the new ISO 31,050, linking emerging risks and resilience.
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There is considerable interest in understanding how inflammatory responses influence cell proliferation and cancer. In this study, we show that the receptor-interacting protein (RIP1), a critical mediator of inflammation and stress-induced NF-kappaB activation, regulates the expression of the epidermal growth factor receptor (EGFR). Mouse embryo fibroblasts (MEFs) derived from RIP1 knockout mice express very high levels of the EGFR. Reconstitution of RIP1(-/-) MEFs with RIP1 results in a lowering of EGFR levels. RIP1 influences EGFR at the mRNA level by regulating the EGFR promoter. Expression of RIP1 inhibits the EGFR promoter. RIP1 downregulates EGFR expression by interfering with the function of Sp1, which is a key activator of EGFR transcription. RIP1 suppresses Sp1 activity and overexpression of Sp1 reverses RIP1-mediated repression of the EGFR promoter. RIP1 is present both in the cytoplasm and in the nucleus. RIP1 coimmunoprecipitates with Sp1 in vivo and binds directly to Sp1 in vitro. A RIP1 mutant lacking the death domain fails to suppress Sp1 activity and the EGFR promoter, suggesting a critical role for the RIP1 death domain in EGFR regulation. Thus, our study identifies a new link between inflammatory and growth factor signaling pathways mediated by RIP1 and provides insight into the mechanism used by RIP1 to regulate EGFR levels.
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Receptores ErbB/metabolismo , NF-kappa B/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Transdução de Sinais , Fator de Transcrição Sp1/metabolismo , Animais , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , DNA/metabolismo , Regulação para Baixo , Receptores ErbB/genética , Humanos , Camundongos , Camundongos Knockout , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteínas Recombinantes/metabolismo , Fator de Transcrição Sp1/antagonistas & inibidoresRESUMO
A theory of the electronic properties of doped fullerenes is proposed in which electronic correlation effects within single fullerene molecules play a central role, and qualitative predictions are made which, if verified, would support this hypothesis. Depending on the effective intrafulllerene electron-electron repulsion and the interfullerene hopping amplitudes (which should depend on the dopant species, among other things), the calculations indicate the possibilities of singlet superconductivity and ferromagnetism.
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A quantitative analysis of a recent model of high-temperature superconductors based on an interlayer tunneling mechanism is presented. This model can account well for the observed magnitudes of the high transition temperatures in these materials and implies a gap that does not change sign, can be substantially anisotropic, and has the same symmetry as the crystal. The experimental consequences explored so far are consistent with the observations.
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The effect of isotopic substitution on the superconducting transition temperature, T(c), in alkali-doped C(60) has been examined. Paradoxically, it is found that a substantial decrease in T(c) with the increasing isotopic mass is possible even when the attractive interaction is not mediated by phonons but is instead of purely electronic origin. In particular, it is shown that the experimentally measured isotopic shifts are consistent with a recently proposed electronic mechanism. Further predictions are presented that can be tested by experiment.
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Manned Mars missions planned in the near future of very low solar activity period and hence higher than acceptable radiation doses due mainly to the Galactic Cosmic Rays (GCR), would require special techniques and technological development for maintaining the good health of the astronauts. The present study is an attempt to make an assessment and characterise the coming years in terms of solar activity and space radiation environment especially due to the abundance of highly energetic heavy ions (known as HZE charged particles). These HZE particle fluxes constitute a major hazard to the astronauts and also to the critical electronic components of the spacecraft. Recent data on the HZE species (from B to Ni) obtained from ACE spacecraft shows a clear enhancement of the particle fluxes between the solar cycle 23 and solar cycle 24 (~between SSN peaks 2002 and 2014) due to the persisting low sunspot numbers of the latter cycle. The peak values of these cosmic ray fluxes occur with a time lag of about a year of the corresponding minimum value of the sunspots of a particular 11-year cycle which is pseudo-periodic in nature. This is demonstrated by the Fourier and Wavelet transform analyses of the long duration (1700-2018) yearly mean sunspot number data. The same time series data is also used to train a Hybrid Regression Neural Network (HRNN) model to generate the predicted yearly mean sunspot numbers for the solar cycle 25 (~2019-2031). The wavelet analysis of this new series of annual sunspot numbers including the predictions up to the end of 2031 shows a clear trend of continuation of the low solar activity and hence continuation of very high HZE fluxes prevailing in Solar cycle 24 into the solar cycle 25 and perhaps beyond.
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Newspaper pulp was found to be a potential adsorbent for removal of copper from aqueous medium. Detail adsorption study of Cu on newspaper pulp was investigated. Batch adsorption study was carried out as a function of contact time, adsorbent dose, temperature (303-323 K). The experimental data was analyzed using Freundlich, Langmuir, Dubinin-Radushkevich (D-R) and Redlich-Peterson (R-P) isotherm models. It was found that Freundlich, Langmuir and R-P models fitted well. pH variation study revealed that the adsorption increased with increase in pH of the solution. Maximum loading capacity was found to be 30 mg g(-1) at 20 mg L(-1) of initial Cu concentration. Adsorption data were analyzed using two kinetic models, Lagergren first order and pseudo second order. It was observed that pseudo second order represented the best correlation. Langmuir isotherm was used to obtain the thermodynamic parameters such as free energy (DeltaG degrees ), enthalpy (DeltaH degrees ) and entropy (DeltaS degrees ) of adsorption. The negative value of free energy and positive value of enthalpy change indicate that the adsorption of Cu on newspaper pulp is a spontaneous process and endothermic. The results of activation energy also confirmed that the adsorption of Cu on newspaper pulp is physical in nature. Present investigation emphasized that newspaper pulp may be utilized as a low cost adsorbent for copper removal.
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Cobre/isolamento & purificação , Papel , Adsorção , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Cinética , Soluções , Temperatura , TermodinâmicaAssuntos
Endoscopia/métodos , Cirurgia do Estribo/métodos , Adolescente , Adulto , Audiometria , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
This theoretical investigation deals with an analysis of pulsatile blood flow in a model bifurcated artery having a stenosis in the parent arterial lumen. The geometry of the bifurcated arterial segment with an implanted stenosis in the parent duct is given an appropriate mathematical shape with the introduction of suitable curvature at the lateral junction and the flow divider. The vascular wall deformability is duly accounted for although the development of atherosclerosis in the arteries reduces its elastic property to some extent. The streaming blood contained in the bifurcated artery is treated to be Newtonian. The flow dynamic analysis applies two-dimensional unsteady incompressible nonlinear Navier-Stokes equations rewritten in the vorticity-stream function formulation. Following a radial coordinate transformation, these equations are solved numerically by a finite difference scheme with the approximate choice of the inlet and boundary conditions in concert with the biophysical point of view. The final numerical results are highlighted at the end of the paper through the exhibition of the wall shear stress and several time-variant patterns of streamlines and vorticity contours of the flow phenomena, which are highly influenced by the severity of the stenosis and the angle of bifurcation. The applicability of the present model is thus established.
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Artérias/fisiologia , Simulação por Computador , Modelos Cardiovasculares , Fluxo Pulsátil/fisiologia , Algoritmos , Animais , Artérias/fisiopatologia , Arteriosclerose/fisiopatologia , Velocidade do Fluxo Sanguíneo , Humanos , Estresse MecânicoRESUMO
Inhibition of p38 kinase blocks the production of tumor-promoting factors in the multiple myeloma (MM) bone marrow microenvironment. Proteasome inhibitors MG132 and bortezomib have been shown to have direct cytotoxic effects on MM cells. We show that a selective inhibitor of p38alpha, SCIO-469, enhances the ability of MG132 and bortezomib to induce the apoptosis of MM cells. Previously, we showed that p38 inhibition with SCIO-469 enhances MM cytotoxicity of bortezomib by inhibiting the transient expression and phosphorylation of Hsp27, a downstream target of p38. Here we show that continued treatment of MM cells with bortezomib leads to a SCIO-469-enhanced downregulation of Hsp27 and to increased MM apoptosis. Furthermore, we show that p38 inhibition enhances the bortezomib-induced MM apoptosis by upregulation of p53 and downregulation of Bcl-X(L) and Mcl-1. In a mouse xenograft plasmacytoma model of MM, we found that inhibiting p38 augments the effects of bortezomib in decreasing MM tumor growth in vivo. Thus, in addition to its role in suppressing an activated MM microenvironment, co-treatment with a p38 inhibitor, such as SCIO-469, may enhance the cytotoxicity of bortezomib by modulating pro-apoptotic and anti-apoptotic factors in MM cells, suggesting great potential for co-therapy.
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Proteínas de Choque Térmico/metabolismo , Indóis/farmacologia , Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Mieloma Múltiplo/metabolismo , Proteínas de Neoplasias/metabolismo , Inibidores de Proteases/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Proteína bcl-X/metabolismo , Administração Oral , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Ácidos Borônicos/administração & dosagem , Ácidos Borônicos/farmacologia , Bortezomib , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo , Ativação Enzimática/efeitos dos fármacos , Proteínas de Choque Térmico HSP27 , Proteínas de Choque Térmico/efeitos dos fármacos , Humanos , Técnicas In Vitro , Indóis/administração & dosagem , Injeções Intravenosas , Leupeptinas/farmacologia , Camundongos , Camundongos Nus , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Chaperonas Moleculares , Mieloma Múltiplo/enzimologia , Proteínas de Neoplasias/efeitos dos fármacos , Inibidores de Proteases/administração & dosagem , Pirazinas/administração & dosagem , Pirazinas/farmacologia , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína bcl-X/efeitos dos fármacosRESUMO
Uniform sized silica and zirconia mixed titania samples were prepared in presence of a surfactant (CETAB) using controlled hydrolysis of corresponding metal alkoxides. Photocatalytic activity towards reduction of lead and cadmium metal in aqueous solution was evaluated both in UV and visible light in a 100 ml capacity reactor. In particular mixing of 10 wt% silica with titania not only increases the surface area of the material but also increases the photocatalytic activity in UV light. Whereas mixing of zirconia with titania proved to be beneficial for visible light reaction. However, addition of hole scavenger increases the activity many folds and complete removal of Pb(2+) and Cd(2+) was possible in 60 min of reaction using synthesized catalysts. Among all the organic hole scavengers used, sodium formate is found to be the most active one. Interestingly quite high metal removal (89%) is also observed in presence of visible light within 60 min of reaction. Thus the above study indicates that the presence of certain oxides in low quantity (10 wt%) with titania can facilitates the photocatalytic process selectively in UV as well as visible light.
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Cádmio/química , Chumbo/química , Luz , Óxidos/química , Titânio/química , Raios Ultravioleta , Catálise , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Oxirredução , Óxidos/síntese química , Fotoquímica , Dióxido de Silício/química , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Zircônio/químicaRESUMO
Adsorption of zinc was studied using chemically modified newspaper pulp as an adsorbent in the aqueous medium. Quantitative chemical analysis showed the presence of trace quantities of some inorganic elements along with phosphorous in TNP. The experimental adsorption data fitted reasonably well to both Freundlich and Langmuir isotherm. pHzpc of TNP was 5.1, which indicated that the adsorbent was more potential for cationic adsorption. The adsorption kinetic data followed a pseudo-second order model for zinc. Optimum Zn(2+) loading was 9.20 mg/g for 10.31 mg/l initial zinc concentration at pH 5.80. Zn(2+) loading on TNP was dependent on initial zinc concentration. TNP was a potential adsorbent for the removal of Zn from the effluent of electroplating industry.