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1.
PLoS One ; 18(1): e0280544, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36662815

RESUMO

BACKGROUND: Electronic media usage is recently considered a modifiable risk factor for overweight and obesity among adolescents. The purpose of this present study was to evaluate the association of electronic media (EM) usage with overweight and obesity among school-going adolescents. METHODS: This cross-sectional study was conducted from October to December 2019 among school-going adolescents (14-16 years old) residing in the Jashore Sadar Upazila, Jashore district of Bangladesh. A standardized questionnaire was used to collect information regarding the socio-economic status, time spent watching television, video games playing, computer, and smart mobile phone use through face-to-face interviews. Age- and sex-specific body mass index (BMI) cut-off values for overweight and obesity were determined for Asian adolescents by the International Obesity Task Force (IOTF). Multinomial logistic regression analysis was carried out to determine the association between electronic media use with overweight and obesity. FINDINGS: The findings suggest that the overall prevalence of overweight and obesity was 13.5% and 25.2%, respectively. Among the total adolescent students, about 49.1% highly (above 3 hours per day) spent their time on EM use whereas 30.6% moderately (≥121 to 180 min/day) use EM. The regression analysis showed that spending high time using total screen-based electronic devices, television viewing, video game playing, computer use, and smartphone use were significantly associated with overweight (RRR: 7.36, 95% CI: 3.64-11.54; RRR: 4.58, 95% CI: 1.46-7.95; RRR: 4.45, 95% CI: 2.75-6.12; RRR: 3.18, 95% CI: 1.87-4.70; RRR: 2.15, 95% CI: 1.23-3.51) and obesity (RRR: 8.72, 95% CI: 4.64-12.54; RRR: 2.89, 95% CI: 1.31-5.21; RRR: 3.88, 95% CI: 1.74-5.13; RRR: 3.08, 95% CI: 1.32-4.86; RRR: 1.19, 95% CI: 0.93-1.48) in adolescents, respectively. CONCLUSION: The results support the total time spent using electronic media was associated with an increased risk of being overweight and obesity. Finally, this study strongly suggests the proper use of electronic media may be necessary to reduce the risk of being overweight and obesity in early adolescents.


Assuntos
Obesidade , Sobrepeso , Masculino , Feminino , Adolescente , Humanos , Sobrepeso/epidemiologia , Estudos Transversais , Obesidade/epidemiologia , Índice de Massa Corporal , Fatores de Risco , Prevalência , Televisão
2.
Asian Pac J Cancer Prev ; 21(6): 1595-1605, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32592353

RESUMO

One of the emerging treatment strategies for cancer particularly for haematological malignancies is natural killer (NK) cell therapy. However, the availability of a best approach to maximize NK cell anticancer potential is still awaited. It is well established that cytokine-induced memory-like NK cells have the potential to differentiate after a short period of preactivation with interleukins-IL-12, IL-15, and IL-18 and exhibit increased responses to cytokine or activating receptor restimulation for weeks to months after preactivation. We demonstrated that NK cells differentiated from CD34+ cells isolated from cord blood show increased antitumor potential in vitro against different cancer cells. Using flow cytometry, we found that NK cells were able to induce apoptosis in cancer cells in vitro. We further analysed surviving gene expression by quantitative real time PCR and reported that NK cells cause down regulation of survivin gene expression in tumor cells. Therefore, NK cell therapy represents a promising immunotherapy for cancers like AML and other haematological malignancies. It concluded that NK cells can be differentiated from CD34+ cells isolated from cord blood ,are able to induce apoptosis and induce increased antitumor potential in vitro against different cancer cells besides cause downregulation of survivin gene expression in tumor cells. Therefore, NK cell therapy represents a promising immunotherapy for different cancer types and haematological malignancies. Furthers studies are necessary to confirm our findings.
.


Assuntos
Citotoxicidade Imunológica/imunologia , Sangue Fetal/imunologia , Interleucina-12/farmacologia , Interleucina-15/farmacologia , Interleucina-18/farmacologia , Células Matadoras Naturais/imunologia , Neoplasias/imunologia , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Citotoxicidade Imunológica/efeitos dos fármacos , Sangue Fetal/citologia , Sangue Fetal/efeitos dos fármacos , Humanos , Técnicas In Vitro , Interferon gama/metabolismo , Células Matadoras Naturais/efeitos dos fármacos , Ativação Linfocitária , Neoplasias/patologia , Neoplasias/prevenção & controle
3.
Chemosphere ; 236: 124326, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31545218

RESUMO

Consumption of eggs leads to generation of huge amount of waste in the form of egg shell, which consists of calcined shell and fibrous membrane. In this study, egg shell membrane (ESM) were chemically modified and used to adsorb congo red from its synthetic aqueous solution. Fourier Transform Infra-red (FTIR) spectra confirmed the presence of hydroxyl, carbonyl and methylene groups in egg shell membrane. Scanning Electron Micrographs (SEM) were also performed to characterize the modified egg shell membrane. Concentration of congo red was measured by using UV spectrophotometer. Effects of various parameters such as initial pH, ESM dosage, contact time and initial congo red concentration were investigated. Highest percentage of adsorption (98%) was obtained at pH 4.5 at a solid to liquid ratio of 1 g-100 ml of congo red solution of concentration of 100 mg/l. Pseudo-second order kinetic model was the best fitted model for this study. The reaction rate constant was found to be 58.04 × 10-3 g mg-1·min-1. The adsorption mechanism was supposed to happen via film diffusion as well as via intraparticle diffusion. Langmuir isotherm gave a better fit for the adsorption compared to the Freundlich isotherm. The maximum monolayer adsorption capacity was determined to be 117.65 mg/g. Thermodynamic parameters (ΔG, ΔH and ΔS) were also studied in this work. The change in enthalpy and change in entropy was found to be 29.217 kJ/mol and 0.124 kJ/mol·K, respectively. The values of ΔG were found to become more negative with increasing temperature.


Assuntos
Vermelho Congo/química , Casca de Ovo/química , Animais
4.
Materials (Basel) ; 10(8)2017 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-28773217

RESUMO

Biosorbents for remediating aquatic environmental media polluted with hazardous heavy metals and metalloids such as Pb(II), Cr(VI), Sb(III and V), and As(III and V) were prepared from lignin waste, orange and apple juice residues, seaweed and persimmon and grape wastes using simple and cheap methods. A lignophenol gel such as lignocatechol gel was prepared by immobilizing the catechol functional groups onto lignin from sawdust, while lignosulfonate gel was prepared directly from waste liquor generated during pulp production. These gels effectively removed Pb(II). Orange and apple juice residues, which are rich in pectic acid, were easily converted using alkali (e.g., calcium hydroxide) into biosorbents that effectively removed Pb(II). These materials also effectively removed Sb(III and V) and As(III and V) when these were preloaded with multi-valent metal ions such as Zr(IV) and Fe(III). Similar biosorbents were prepared from seaweed waste, which is rich in alginic acid. Other biosorbents, which effectively removed Cr(VI), were prepared by simply treating persimmon and grape wastes with concentrated sulfuric acid.

5.
Int Sch Res Notices ; 2014: 751952, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-27433529

RESUMO

Scarcity of pure drinking water during the dry season (November-March) is a major problem in Bangladesh, which needs to be addressed. This crisis has been further aggravated due to surging populations. Rainwater can provide some of the cleanest naturally occurring water and can hold a great potential in dealing with the current challenge of acute arsenic poisoning as well as physical water scarcity in many parts of Bangladesh. In this connection, rainwater harvesting (RWH) system has been constructed in a very remote and rural village in Khulna, Bangladesh, for a 4-membered household. It consists of a concrete catchment of 40 m(2) area, a supporting and collection system made of PVC pipes, and two locally available plastic storage tanks having capacity of 2000 L each. The study also investigates the quality aspects of the stored rainwater, which include measurement of pH, alkalinity, hardness, total dissolved solids (TDS), iron, chloride, nitrate, and turbidity, using standard methods. The results showed that not only the quality of harvested rainwater is good but also the amount of water is enough for a 4-membered household to meet its domestic use throughout the year.

6.
Environ Technol ; 33(7-9): 845-50, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22720408

RESUMO

This investigation provides new insights into the effective removal of tetrafluoroborate (BF4-) by means of bio-sorption on waste generated in the orange juice industry. It was undertaken to evaluate the feasibility of zirconium (IV)-loaded saponified orange waste gel for BF4- removal from an aqueous solution. Batch adsorption experiments were carried out to study the influence of various factors such as pH, presence of competing anions, contact time, initial BF4- concentration and temperature on the adsorption of BF4-. The optimum BF4- removal was observed in the equilibrium pH region 2-3. The presence of coexisting anions showed no adverse effect on BF4- removal except SO4(2-). The equilibrium data at different temperatures were reasonably interpreted by the Langmuir adsorption isotherm and the maximum adsorption capacities were evaluated as 2.65, 3.28, 3.87 and 4.77 mmol g(-1) at 293, 298, 303 and 313 K, respectively. Thermodynamic parameters such as deltaGo, deltaHo and deltaSo indicated that the nature of BF4- adsorption is spontaneous and endothermic. The results obtained from this study demonstrate the potential usability of orange waste after juicing as a good BF4- selective adsorbent.


Assuntos
Ácidos Bóricos/isolamento & purificação , Citrus sinensis/química , Poluentes Químicos da Água/isolamento & purificação , Zircônio/química , Adsorção , Ânions/química , Biomassa , Boratos , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
7.
Bioresour Technol ; 102(13): 6857-62, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21550234

RESUMO

Persimmon waste was chemically modified by crosslinking with concentrated sulfuric acid to obtain a novel kind of adsorption gel, which was termed as crosslinked persimmon tannin (CPT), hereinafter. The adsorption behaviors of Mo(VI) with other coexisting metal ions onto the CPT gel were investigated. The gel exhibited selectivity only for Mo(VI) ions evidenced by the high value of separation factor of molybdenum and rhenium (ß(Mo/Re)=164.37), and the adsorption mechanism of Mo(VI) as a multispecies was studied. The molybdenum adsorption behavior conforms to the Langmuir model with a remarkably high adsorption capacity of 0.56 mol/kg. A kinetic study for the adsorption of molybdenum at various temperatures confirmed that the endothermic adsorption process followed pseudo-second order kinetics. Moreover, its excellent adsorption properties and applicability for Mo(VI) were demonstrated by the removal and separation of Mo(VI) from different Mo-Re containing industrial wastewaters.


Assuntos
Diospyros/química , Molibdênio/isolamento & purificação , Rênio/isolamento & purificação , Taninos/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção/efeitos dos fármacos , Biodegradação Ambiental/efeitos dos fármacos , Carvão Vegetal/química , Reagentes de Ligações Cruzadas/farmacologia , Diospyros/efeitos dos fármacos , Géis , Ácido Clorídrico/farmacologia , Resíduos Industriais/análise , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo
8.
J Hazard Mater ; 186(2-3): 1855-61, 2011 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-21237565

RESUMO

Astringent persimmon was chemically cross-linked by formaldehyde to obtain a novel kind of adsorption gel, which was named as APF gel. The adsorption behaviors of Mo(VI) and Re(VII) along with other coexisting metals onto the APF gel were studied in the present paper. The APF gel was found to be effective for the adsorption of Mo(VI) while the gel is almost completely inert toward rhenium and calcium over the whole hydrochloric acid concentration region. The APF gel has a low affinity for iron, copper, lead, nickel, manganese and zinc ions when the concentration of HCl is higher than 1 mol/L. The gel exhibited selectivity only for Mo(VI) with a remarkably high adsorption capacity 1.05 mol/kg, and the adsorption behavior obeys the Langmuir model. According to the thermodynamic and kinetic studies, the endothermic adsorption process followed pseudo-second order kinetics. Also, its excellent adsorption characteristics for Mo(VI) were confirmed by the adsorption and elution tests using a column packed with the APF gel. The result provides a new approach for the recovery of Mo(VI) from a industrial waste effluent.


Assuntos
Diospyros/química , Molibdênio/química , Molibdênio/isolamento & purificação , Rênio/química , Rênio/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Adsorção , Algoritmos , Flavonoides/análise , Formaldeído/análise , Ácido Clorídrico/química , Concentração de Íons de Hidrogênio , Resíduos Industriais/análise , Metais/análise , Fenóis/análise , Polifenóis , Taninos/análise , Termodinâmica
9.
J Hazard Mater ; 172(2-3): 721-8, 2009 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-19726128

RESUMO

Zr(IV) and Fe(III) ions were loaded onto an orange waste precursor to prepare a metal-loaded orange waste gel, which was investigated for the adsorptive removal and recovery of antimony (III and V) from an aqueous environment. The loading capacity of the orange waste for Zr(IV) and Fe(III) was found to be 1.40 and 1.87 mmol/g, respectively. The maximum batch mode sorption capacity of the Zr(III)-loaded saponified orange waste (SOW) gel was found to be 0.94 mmol/g for Sb(III) and 1.19 mmol/g for Sb(V). A nearly similar result was found for the Fe(III)-loaded SOW gel with the sorption capacity for Sb(III) and Sb(V) being 1.12 and 1.19 mmol/g, respectively. The presence of a variety of anionic species such as carbonate, chloride, nitrate and sulfate had no influence on the adsorption of both Sb(III) and Sb(V). A column adsorption-elution test demonstrated the utility of this system in continuous mode. Selective sulfide precipitation of antimony is one of the major findings in the present work, which clearly suggests a means of effective recovery of antimony from solution containing antimony and other metal ions. Due to their low cost, availability and significantly high adsorption capacity, the metal-loaded gels are expected to be effectively employed for the removal and recovery of antimony from aqueous solution, thus leading to the establishment of a greener environment.


Assuntos
Antimônio/isolamento & purificação , Citrus sinensis , Resíduos Industriais , Metais/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Géis/química , Ferro , Purificação da Água/métodos , Zircônio
10.
J Environ Sci (China) ; 21(12): 1753-60, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20131609

RESUMO

Ashes from sewage sludge incineration have a high phosphorus content, approximately 8% (W/W), which indicates a potential resource of the limiting nutrient. Incineration of sewage sludge with subsequent recovery of phosphorus is a relatively new sludge treatment technique. In this article, the leaching of phosphorus by using sulfuric acid as well as hydrochloric acid by means of several batch experiments was presented. At the same time a selective recovery of phosphorus by adsorption was also discussed. The effects of acid concentration, temperature and time on extraction were studied. The phosphorus leaching increased with the increase in acid concentration and temperature. Kinetic studies showed that the complete leaching of phosphorus took place in less than 4 h. Selective adsorption of phosphorus by using orange waste gel provided a hint for recovery of this natural resource, which eventually could meet the ever-increasing requirement for phosphorus. The overall results indicated that the incinerated sewage sludge ash can be treated with acid to efficiently recover phosphorus and thus can be considered a potentially renewable source of phosphorus.


Assuntos
Fósforo/isolamento & purificação , Esgotos/química , Adsorção , Ácido Clorídrico/química , Resíduos Industriais , Cinética , Ácidos Sulfúricos/química , Temperatura
11.
J Hazard Mater ; 154(1-3): 1066-74, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18093733

RESUMO

Orange waste, produced during juicing has been loaded with zirconium(IV) so as to examine its adsorption behavior for both As(V) and As(III) from an aquatic environment. Immobilization of zirconium onto the orange waste creates a very good adsorbent for arsenic. Adsorption kinetics of As(V) at different concentrations are well described in terms of pseudo-second-order rate equation with respect to adsorption capacity and correlation coefficients. Arsenate was strongly adsorbed in the pH range from 2 to 6, while arsenite was strongly adsorbed between pH 9 and 10. Moreover, equimolar (0.27 mM) addition of other anionic species such as chloride, carbonate, and sulfate had no influence on the adsorption of arsenate and arsenite. The maximum adsorption capacity of the Zr(IV)-loaded SOW gel was evaluated as 88 mg/g and 130 mg/g for As(V) and As(III), respectively. Column adsorption tests suggested that complete removal of arsenic was achievable at up to 120 Bed Volumes (BV) for As(V) and 8 0BV for As(III). Elution of both arsenate and arsenite was accomplished using 1 M NaOH without any leakage of the loaded zirconium. Thus this efficient and abundant bio-waste could be successfully employed for the remediation of an aquatic environment polluted with arsenic.


Assuntos
Arseniatos/química , Arsenitos/química , Citrus sinensis , Poluentes Químicos da Água/química , Purificação da Água/métodos , Zircônio/química , Adsorção , Bebidas , Indústria Alimentícia , Géis , Concentração de Íons de Hidrogênio , Resíduos Industriais , Cinética , Mineração , Resíduos , Abastecimento de Água
12.
J Colloid Interface Sci ; 312(2): 214-23, 2007 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-17485100

RESUMO

Phosphate removal from an aquatic environment was investigated using La(III)-, Ce(III)- and Fe(III)-loaded orange waste. The adsorption isotherm, the kinetics of adsorption and the effect of pH on the removal of phosphate have been examined. The % removal of phosphate using La(III)- and Ce(III)-loaded orange waste gel increases with increasing pH within the range of 5-7 but decreases when the pH is increased beyond this range. The equilibrium sorption was observed to be in accordance with Langmuir type adsorption and the maximum adsorption capacity was evaluated as 13.94 mg P/g of dry gel for all the three types of gels. Kinetic studies revealed that 15 h is enough to reach equilibrium in batch experiments. Fixed bed sorption experiments confirmed the continuous phosphate adsorption and elution capability of such simply modified gels. Due to their low cost, availability and significantly high adsorption capability, metal-loaded SOW gels can be effectively employed for the removal of phosphate from water.

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