RESUMO
Magnetite nanoparticles use for the remediation of toxic metal ions. Therefore, the scope of green synthesis of magnetite nanoparticles from Hevea bark extract, and application of these particles for the environmental remediation of Cd and Na tested. Mixing of 10.0 mL each bark extract (1.0 g in 25.0 mL H2O) and iron solution (10.0 mM FeCl3 and 5.0 mM FeCl2) resulted formation of semicrystalline magnetite nanoparticles having magnetic saturation at 104 G. The particles characterized with the help of scanning electron microscopy, energy dispersive spectroscopy, Uv-vis spectroscopy, vibrating sample magnetometry, powder X-Ray diffraction, Fourier-transform infrared spectroscopy, and differential thermal analysis coupled with thermogravimetry. The phytochemicals responsible for priming and coating of nanoparticle were phenolics, especially benzoic acid derivatives. Adsorption of metal ions to nanoparticles followed pseudo-second-order model. Maximum Cd and Na adsorption capacity were 37.03 and 3.95 mg g-1 respectively. The difference in Cd and Na adsorption capacity was the result of multilayer and monolayer adsorption processes respectively. Highest metal ion adsorption occurred at temperature 10.0-20.0 °C and pH 6.0. Metal adsorption property of the nanoparticles decreased the accumulation of Cd and Na in rice plants. The plant growth promotion effects of nanoparticles explained regarding biomass, osmolyte content, and oxidative stress tolerance. Therefore, the nanoparticles produced in the study can use as a magnetically separable nano sorbent of metal ions as well as ameliorant of metal stress in rice.
Assuntos
Cádmio/química , Hevea/metabolismo , Nanopartículas de Magnetita/química , Metais/toxicidade , Oryza/metabolismo , Casca de Planta/metabolismo , Sódio/química , Poluentes Químicos da Água/toxicidade , AdsorçãoRESUMO
Environmental cadmium (Cd) sources have increased in mangrove sediments in recent decades, inducing cellular damage to many plants. Avicennia schaueriana is abundant in mangrove sites and has been subject to Cd contamination. The possible effects of Cd toxicity and the structural and physiological disturbances to this plant were studied. Can this plant express early cellular tolerance mechanisms to such metal contamination? Seedlings of A. schaueriana were collected from sites of their natural occurrence, placed in plastic pots containing nutrient solution for 60 days, and subsequently exposed to increasing Cd concentrations for 5 days under experimental conditions. The anatomical, ultrastructural and physiological changes induced by Cd were analysed. Cd accumulated mainly in the root system and in pneumatophores, stems and leaves, induced differential accumulation of mineral nutrients, but did not induce necrosis or changes in leaf anatomy. However, there was a decrease in starch grains and an increase in deposited electron-dense material in the cortex and vascular bundles. Cd induced both increases in calcium (Ca) content in shoots and Ca oxalate crystal precipitation in leaf mesophyll and was detected in crystals and in the secretion of salt glands. Our observations and experimental results provide evidence of Cd tolerance in A. schaueriana. As a new feature, despite the clear cellular physiological disorders, this plant is able to eliminate Cd through leaf salt glands and immobilise it in Ca crystals, representing fast mechanisms for Cd exclusion and complexation in leaves in heavy metal coastal polluted marine ecosystems.
Assuntos
Avicennia/efeitos dos fármacos , Cádmio/toxicidade , Folhas de Planta/metabolismo , Avicennia/metabolismo , Avicennia/ultraestrutura , Cádmio/metabolismo , Cálcio/metabolismo , Microscopia Eletrônica de Transmissão , Raízes de Plantas/metabolismo , Caules de Planta/metabolismo , Plântula/efeitos dos fármacos , Plântula/metabolismo , Plântula/ultraestruturaRESUMO
Dyslipidemia and obesity are especially prevalent in populations with Amerindian backgrounds, such as Mexican-Americans, which predispose these populations to cardiovascular disease. Here we design an approach, known as the cross-population allele screen (CPAS), which we conduct prior to a genome-wide association study (GWAS) in 19,273 Europeans and Mexicans, in order to identify Amerindian risk genes in Mexicans. Utilizing CPAS to restrict the GWAS input variants to only those differing in frequency between the two populations, we identify novel Amerindian lipid genes, receptor-related orphan receptor alpha (RORA) and salt-inducible kinase 3 (SIK3), and three loci previously unassociated with dyslipidemia or obesity. We also detect lipoprotein lipase (LPL) and apolipoprotein A5 (APOA5) harbouring specific Amerindian signatures of risk variants and haplotypes. Notably, we observe that SIK3 and one novel lipid locus underwent positive selection in Mexicans. Furthermore, after a high-fat meal, the SIK3 risk variant carriers display high triglyceride levels. These findings suggest that Amerindian-specific genetic architecture leads to a higher incidence of dyslipidemia and obesity in modern Mexicans.
Assuntos
Hipercolesterolemia/genética , Hipertrigliceridemia/genética , Indígenas Norte-Americanos/genética , Obesidade/genética , Adulto , Apolipoproteína A-V , Apolipoproteínas A/genética , Estudos de Casos e Controles , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 8/genética , Dislipidemias/genética , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Haplótipos , Humanos , Lipase Lipoproteica/genética , Modelos Logísticos , Masculino , México/etnologia , Pessoa de Meia-Idade , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Polimorfismo de Nucleotídeo Único , Proteínas Quinases/genética , População Branca/genética , Adulto JovemRESUMO
BACKGROUND: The Mexican population and others with Amerindian heritage exhibit a substantial predisposition to dyslipidemias and coronary heart disease. Yet, these populations remain underinvestigated by genomic studies, and to date, no genome-wide association (GWA) studies have been reported for lipids in these rapidly expanding populations. METHODS AND FINDINGS: We performed a two-stage GWA study for hypertriglyceridemia and low high-density lipoprotein cholesterol (HDL-C) in Mexicans (n=4361), and identified a novel Mexican-specific genome-wide significant locus for serum triglycerides (TGs) near the Niemann-Pick type C1 protein gene (p=2.43×10(-08)). Furthermore, three European loci for TGs (APOA5, GCKR and LPL), and four loci for HDL-C (ABCA1, CETP, LIPC and LOC55908) reached genome-wide significance in Mexicans. We used cross-ethnic mapping to narrow three European TG GWA loci, APOA5, MLXIPL, and CILP2 that were wide and contained multiple candidate variants in the European scan. At the APOA5 locus, this reduced the most likely susceptibility variants to one, rs964184. Importantly, our functional analysis demonstrated a direct link between rs964184 and postprandial serum apoAV protein levels, supporting rs964184 as the causative variant underlying the European and Mexican GWA signal. Overall, 52 of the 100 reported associations from European lipid GWA meta-analysis generalised to Mexicans. However, in 82 of the 100 European GWA loci, a different variant other than the European lead/best-proxy variant had the strongest regional evidence of association in Mexicans. CONCLUSIONS: This first Mexican GWA study of lipids identified a novel GWA locus for high TG levels; used the interpopulation heterogeneity to significantly restrict three previously known European GWA signals, and surveyed whether the European lipid GWA SNPs extend to the Mexican population.
Assuntos
Apolipoproteínas A/genética , Loci Gênicos/genética , Hipertrigliceridemia/genética , Hipoalfalipoproteinemias/genética , Indígenas Norte-Americanos/genética , Triglicerídeos/genética , Apolipoproteína A-V , Apolipoproteínas A/sangue , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Hipertrigliceridemia/etnologia , Hipoalfalipoproteinemias/etnologia , Desequilíbrio de Ligação , Proteínas de Membrana/genética , Proteínas de Membrana Transportadoras , México , Polimorfismo de Nucleotídeo Único/genética , Triglicerídeos/sangue , População Branca/genéticaRESUMO
Bihar, India has been in the grip of kala-azar for many years. Its rampant and severe spread has made life miserable in most parts of the state. Such conditions require a comprehensive understanding of this affliction. The numbers coming out of the districts prone to the disease in the north and south Ganges have provided us with several startling revelations, as there are striking uniformities on both sides, including similar vegetation, water storage facilities, house construction and little change in risk factors. The northern areas have been regularly sprayed with DDT since 1977, but eradication of the disease appears to be a distant dream. In 2007 alone, there were as many as 37,738 cases in that region. In contrast, the southern districts of Patna and Nalanda have never had the disease in its epidemic form and endemic disease has been present in only some pockets of the two districts. In those cases, two rounds of spraying with DDT had very positive results, with successful control and no new established foci. In addition, an eleven-year longitudinal study of the man hour density and house index for the vector Phlebotomus argentipes demonstrated that they were quite high in Patna and Nalanda and quite low in north Bihar. Given these facts, an attempt has been made to unravel the role of P. argentipes saliva (salivary gland) in the epidemiology of kala-azar. It was determined that patchy DDT spraying should be avoided for effective control of kala-azar.
Assuntos
DDT , Insetos Vetores/crescimento & desenvolvimento , Inseticidas , Leishmaniose Visceral/prevenção & controle , Phlebotomus/crescimento & desenvolvimento , Análise de Variância , Animais , Habitação/classificação , Habitação/estatística & dados numéricos , Humanos , Umidade , Índia/epidemiologia , Insetos Vetores/imunologia , Resistência a Inseticidas , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/transmissão , Estudos Longitudinais , Controle de Mosquitos , Phlebotomus/imunologia , Densidade Demográfica , Glândulas Salivares/imunologiaRESUMO
Bihar, India has been in the grip of kala-azar for many years. Its rampant and severe spread has made life miserable in most parts of the state. Such conditions require a comprehensive understanding of this affliction. The numbers coming out of the districts prone to the disease in the north and south Ganges have provided us with several startling revelations, as there are striking uniformities on both sides, including similar vegetation, water storage facilities, house construction and little change in risk factors. The northern areas have been regularly sprayed with DDT since 1977, but eradication of the disease appears to be a distant dream. In 2007 alone, there were as many as 37,738 cases in that region. In contrast, the southern districts of Patna and Nalanda have never had the disease in its epidemic form and endemic disease has been present in only some pockets of the two districts. In those cases, two rounds of spraying with DDT had very positive results, with successful control and no new established foci. In addition, an eleven-year longitudinal study of the man hour density and house index for the vector Phlebotomus argentipes demonstrated that they were quite high in Patna and Nalanda and quite low in north Bihar. Given these facts, an attempt has been made to unravel the role of P. argentipes saliva (salivary gland) in the epidemiology of kala-azar. It was determined that patchy DDT spraying should be avoided for effective control of kala-azar.
Assuntos
Animais , Humanos , DDT , Inseticidas , Insetos Vetores/crescimento & desenvolvimento , Leishmaniose Visceral/prevenção & controle , Phlebotomus/crescimento & desenvolvimento , Análise de Variância , Umidade , Habitação/classificação , Habitação/estatística & dados numéricos , Resistência a Inseticidas , Índia/epidemiologia , Insetos Vetores/imunologia , Estudos Longitudinais , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/transmissão , Controle de Mosquitos , Densidade Demográfica , Phlebotomus/imunologia , Glândulas Salivares/imunologiaRESUMO
Uma enzima extracelular celulolítica produzida por Pseudomonas sp. foi ativa sobre células de Xanthomonas campestris mortas pelo calor. A atividade lítica causou a digestão enzimática de goma xantana de X. campestris. A digestão foi eficiente tanto para xantana nativa altamante viscosa (2,0 per center w/v) como para xantana comercial Sigma (2,5 per center w/v). Observações por microscopia eletrônica de varredura demonstraram a ação celulolítica sobre células de X. campestris.
Assuntos
Pseudomonas , Xanthomonas campestris , Ativadores de EnzimasRESUMO
An extracellular cell lytic enzyme from Pseudomonas sp. was active on heat killed cells of Xanthomonas campestris. The lytic activity caused enzymatic digestion of X.campestris xanthan gum. Digestion was effective for highly viscous native xanthan 2.0% (w/v) and 2.5% (w/v) commercial Sigma xanthan. Scanning electron microscopy and SDS-PAGE observations confirmed the cell lytic action on X.campestris cells.
Uma enzima extracelular celulolítica produzida por Pseudomonas sp. foi ativa sobre células de Xanthomonas campestris mortas pelo calor. A atividade lítica causou a digestão enzimática de goma xantana de X. campestris. A digestão foi eficiente tanto para xantana nativa altamante viscosa (2,0% w/v) como para xantana comercial Sigma (2,5% w/v). Observações por microscopia eletrônica de varredura demonstraram a ação celulolítica sobre células de X. campestris.