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1.
Chemosphere ; 262: 128411, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182135

RESUMO

Biocatalytic degradation technology has received a great deal of attention in water treatment because of its advantages of high efficiency, environmental friendliness, and no secondary pollution. Herein, for the first time, horseradish peroxidase and mediator syringaldehyde were co-immobilized into functionalized calcium alginate composite beads grafted with glycidyl methacrylate and dopamine. The resultant biocatalyst of the co-immobilized horseradish peroxidase-syringaldehyde system has displayed excellent catalytic performance to degrade indole in water. The degradation rate of 100% was achieved in the presence of hydrogen peroxide even if the indole concentration was changing from 25 mg/L to 500 mg/L. If only the free enzyme was used under the identical water treatment conditions, the degradation of indole could hardly be observed even when the concentration of indole is low at 25 mg/L. This was attributed to the effective co-immobilization of the enzyme and the mediator so that the catalytic activity of horseradish peroxidase and the synergistic catalytic action of syringaldehyde could be fully developed. Furthermore, while the spherical catalyst was operated in succession and reused for four cycles in 50 mg/L indole solution, the degradation rate remained 91.8% due to its considerable reusability. This research demonstrated and provided a novel biocatalytic approach to degrade indole in water by the co-immobilized horseradish peroxidase-syringaldehyde system as biocatalyst.


Assuntos
Benzaldeídos/química , Indóis/química , Alginatos , Biocatálise , Catálise , Enzimas Imobilizadas/metabolismo , Peroxidase do Rábano Silvestre/metabolismo , Peróxido de Hidrogênio/metabolismo
2.
Chemosphere ; 262: 127905, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182152

RESUMO

Pot experiments were conducted to study combined effects of Ca and Cd on contents of Cd and Ca, and membrane transporters activities (CC (calcium channel protein), ATPase and CAXs (cationic/H+ antiporter) of two-year old Panax notoginseng with application of different concentrations of Ca2+ (0, 180 and 360 mgkg-1, prepared by Ca(OH)2 and CaCl2, respectively) under Cd2+ (0, 0.6, 6.0, and 12.0 mgkg-1, prepared by CdCl2•2.5H2O) treatments. The results showed that soil available Cd contents decreased with Ca(OH)2 and CaCl2 application. Soil pH value increased with Ca(OH)2 application. The contents of Cd in all parts of P. notoginseng increased with the increase in Cd treatment concentrations. The Cd content of P. notoginseng decreased with Ca(OH)2 and CaCl2 treatments. The activities of CC and ATPase in the main root of P. notoginseng decreased with the increase in Cd treatment concentrations and application of CaCl2. The activities of CC and ATPase increased with Ca(OH)2application. The activity of CAXs in the main root of P. notoginseng increased with the increase of Cd treatment concentration. The results indicate that Ca and Cd should be both related to membrane transporters activities and activities of CC, ATPase and CAXs are promoted by cooperation of Ca2+and OH+, which suggest the Ca(OH)2 application should be better than application of CaCl2 for Cd detoxification.


Assuntos
Cádmio/toxicidade , Cálcio/metabolismo , Panax notoginseng/fisiologia , Poluentes do Solo/toxicidade , Adenosina Trifosfatases/análise , Cádmio/análise , Proteínas de Membrana Transportadoras/metabolismo , Panax notoginseng/química , Raízes de Plantas/metabolismo , Solo/química , Poluentes do Solo/análise
3.
Ann Lab Med ; 41(2): 129-138, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33063674

RESUMO

Since its first report in December 2019, coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has rapidly emerged as a pandemic affecting nearly all countries worldwide. As the COVID-19 pandemic progresses, the need to identify genetic risk factors for susceptibility to this serious illness has emerged. Host genetic factors, along with other risk factors may help determine susceptibility to respiratory tract infections. It is hypothesized that the ACE2 gene, encoding angiotensin-converting enzyme 2 (ACE2), is a genetic risk factor for SARS-CoV-2 infection and is required by the virus to enter cells. Together with ACE2, transmembrane protease serine 2 (TMPRSS2) and dipeptidyl peptidase-4 (DPP4) also play an important role in disease severity. Evaluating the role of genetic variants in determining the direction of respiratory infections will help identify potential drug target candidates for further study in COVID-19 patients. We have summarized the latest reports demonstrating that ACE2 variants, their expression, and epigenetic factors may influence an individual's susceptibility to SARS-CoV-2 infection and disease outcome.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/patologia , Variação Genética , Pneumonia Viral/patologia , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/virologia , Dipeptidil Peptidase 4/genética , Dipeptidil Peptidase 4/metabolismo , Suscetibilidade a Doenças , Expressão Gênica , Humanos , Pandemias , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/virologia , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Índice de Gravidade de Doença
4.
Ann Lab Med ; 41(2): 225-229, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33063685

RESUMO

In response to the ongoing coronavirus disease 2019 (COVID-19) pandemic, an online laboratory surveillance system was established to monitor severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) real-time reverse transcription-PCR (rRT-PCR) testing capacities and results. SARS-CoV-2 rRT-PCR testing data were collected from 97 clinical laboratories, including 84 medical institutions and 13 independent clinical laboratories in Korea. We assessed the testing capacities to utilize SARS-CoV-2 rRT-PCR based on surveillance data obtained from February 7th to June 4th, 2020 and evaluated positive result characteristics according to the reagents used and sample types. A total of 1,890,319 SARS-CoV-2 rRT-PCR testing were performed, 2.3% of which were positive. Strong correlations were observed between the envelope (E) gene and RNA-dependent RNA polymerase (RdRp)/nucleocapsid (N) genes threshold cycle (Ct) values for each reagent. No statistically significant differences in gene Ct values were observed between the paired upper and lower respiratory tract samples, except in the N gene for nasopharyngeal swab and sputum samples. Our study showed that clinical laboratories in Korea have rapidly expanded their testing capacities in response to the COVID-19 outbreak, with a peak daily capacity of 34,193 tests. Rapid expansion in testing capacity is a critical component of the national response to the ongoing pandemic.


Assuntos
Betacoronavirus/genética , Serviços de Laboratório Clínico/estatística & dados numéricos , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/virologia , Humanos , Laboratórios Hospitalares , Pandemias , Pneumonia Viral/virologia , RNA Replicase/genética , RNA Viral/genética , RNA Viral/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , República da Coreia , Proteínas do Envelope Viral/genética , Proteínas Virais/genética
5.
Food Chem ; 334: 127428, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32688173

RESUMO

Aspergillus quadrilineatus endo-ß-mannanase effectively degraded konjac glucomannan (66.09% w/v), copra meal (38.99% w/v) and locust bean galactomannan (20.94% w/v). High performance liquid chromatography (HPLC) analysis of KG hydrolysate indicated its mannooligosaccharides (MOS) content (656.38 mg/g) with high amounts of DP 5 oligosaccharide. Multi-scale characterization of mannan hydrolysate was done using FTIR and 13C NMR which revealed α and ß form of galactose or glucose in MOS, respectively. CM and LBG hydrolysates (1 mg/mL) have shown cytotoxic effect and reduced cell viability of Caco-2 cells by 45% and 62%, respectively. MOS DP (1-4) derived from LBG supported better Lactobacilli biofilm formation as compared to KG hydrolysate containing high DP MOS (5-7). Lactobacilli effectively fermented MOS to generate acetate and propionate as main short chain fatty acids. Lactobacilli produced leucine, isoleucine and valine as branched chain amino acids when grown on LBG hydrolysate.


Assuntos
Mananas/química , Oligossacarídeos/farmacologia , Prebióticos , beta-Manosidase/metabolismo , Aspergillus/enzimologia , Biofilmes , Células CACO-2 , Fermentação , Humanos , Hidrólise , Lactobacillus/crescimento & desenvolvimento , Espectroscopia de Ressonância Magnética , Mananas/metabolismo , Oligossacarídeos/química , Oligossacarídeos/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , beta-Manosidase/química
6.
Food Chem ; 334: 127475, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32688176

RESUMO

Although numerous types of organisms have been used to enrich selenium, a low-cost and efficient organism is yet to be identified. This study aimed to develop a new means of selenium enrichment using Tenebrio molitor larvae. Our results indicated that the total selenium content in larvae was increased 83-fold to 54.21 ± 1.25 µg/g, and of this content, organic selenium accounted for over 97% after feeding the larvae with 20 µg/g of sodium selenite. Selenium was distributed unequally in the protein fraction with following order: alkali-soluble protein-bound selenium (36.32%) > salt-soluble protein-bound selenium (19.41%) > water-soluble protein-bound selenium (17.03%) > alcohol-soluble protein-bound selenium (3.21%). Additionally, 81% of the selenium within the soluble proteins was distributed in subunits possessing molecular weights of <40 kDa. After hydrolysis by alcalase, the protein hydrolysate of selenium-enriched larvae possessing 75% selenium recovery exhibited stronger antioxidant and immunoregulatory activities than those of regular larvae.


Assuntos
Antioxidantes/farmacologia , Fatores Imunológicos/farmacologia , Proteínas de Insetos/metabolismo , Hidrolisados de Proteína/farmacologia , Selênio/farmacocinética , Tenebrio/metabolismo , Adulto , Aminoácidos/análise , Aminoácidos/metabolismo , Animais , Antioxidantes/metabolismo , Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Hidrólise , Fatores Imunológicos/metabolismo , Proteínas de Insetos/farmacologia , Larva/efeitos dos fármacos , Larva/metabolismo , Camundongos , Hidrolisados de Proteína/metabolismo , Células RAW 264.7 , Selênio/análise , Subtilisinas/química , Subtilisinas/metabolismo , Tenebrio/efeitos dos fármacos
7.
Food Chem ; 334: 127479, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32688181

RESUMO

Calcium treatment effects on malate metabolism and the GABA pathway in 'Cripps Pink' apple fruit during storage were investigated. Postharvest apple fruit treated with 1% and 4% calcium chloride solutions were stored at 25 ± 1 °C. The 4% calcium treatment suppressed declines in titratable acidity and malate content and increased succinate and oxalate concentrations. Calcium treatment also reduced the respiration rate and decreased ethylene production peak during storage. Moreover, 4% calcium treatment significantly enhanced cyNAD-MDH and PEPC activities and upregulated MdMDH1, MdMDH2, MdPEPC1 and MdPEPC2 expression while inhibiting cyNADP-ME and PEPCK activities and downregulating MdME1, MdME4 and MdPEPCK2 expression. Surprisingly, calcium treatment changed the content of some free amino acids (GABA, proline, alanine, aspartic acid and glutamate), two of which (glutamate and GABA) are primary metabolites of the GABA pathway. Furthermore, calcium application enhanced GABA pathway activity by increasing MdGAD1, MdGAD2, MdGABA-T1/2 and MdSSADH transcript levels.


Assuntos
Cálcio/farmacologia , Frutas/efeitos dos fármacos , Malatos/metabolismo , Malus/efeitos dos fármacos , Malus/metabolismo , Ácido gama-Aminobutírico/metabolismo , Aminoácidos/análise , Aminoácidos/metabolismo , Etilenos/metabolismo , Qualidade dos Alimentos , Frutas/química , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Malus/química , Malus/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
8.
Sci Total Environ ; 750: 141532, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32858292

RESUMO

Coronavirus disease 2019 (COVID-19), an acute respiratory disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has rapidly developed into a pandemic throughout the world. This disease is a highly infectious novel coronavirus and can affect people of all ages. Previous reports observed that particulate matter (PM) provided a platform for intermixing with viruses (i.e., influenza). However, the role of PM in SARS-CoV-2 transmission remains unclear. In this paper, we propose that PM plays a direct role as a "carrier" of SARS-CoV-2. SARS-CoV-2 is reported to have a high affinity for the angiotensin-converting enzyme 2 (ACE2) receptor. Indirectly, exposure to PM increases ACE2 expression in the lungs which facilitates SARS-CoV-2 viral adhesion. Thus, the high risk of SARS-CoV-2 in heavily polluted regions can be explained by upregulation of ACE2 caused by PM. PM could be both a direct and indirect transmission model for SARS-CoV-2 infection.


Assuntos
Infecções por Coronavirus , Coronavirus , Pandemias , Pneumonia Viral , Betacoronavirus , Humanos , Material Particulado , Peptidil Dipeptidase A/metabolismo
9.
Adv Exp Med Biol ; 1287: 105-122, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33034029

RESUMO

The NOTCH pathway is critical for the development of many cell types including the squamous epithelium lining of cutaneous and mucosal surfaces. In genetically engineered mouse models, Notch1 acts as one of the first steps to commit basal keratinocytes to terminally differentiate. Similarly, in human head and neck squamous cell cancers (HNSCCs), NOTCH1 is often lost consistent with its essential tumor-suppressive role for initiating keratinocyte differentiation. However, constitutive NOTCH1 activity in the epithelium results in expansion of the spinous keratinocyte layers and impaired terminal differentiation is consistent with the role of NOTCH1 as an oncogene in other cancers, especially in T-cell acute lymphoblastic leukemia. We have previously observed that NOTCH1 plays a dual role as both a tumor suppressor and oncogene, depending on the mutational context of the tumor. Namely, gain or loss or NOTCH1 activity promotes the development of human papillomavirus (HPV)-associated cancers. The additional HPV oncogenes likely disrupt the tumor-suppressive activities of NOTCH and enable the oncogenic pathways activated by NOTCH to promote tumor growth. In this review, we detail the role of NOTCH pathway in head and neck cancers with a focus on HPV-associated cancers.


Assuntos
Carcinogênese , Neoplasias Bucais/metabolismo , Neoplasias Bucais/virologia , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais , Animais , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/virologia , Humanos , Infecções por Papillomavirus/virologia
10.
Chemosphere ; 262: 127810, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32763578

RESUMO

Copper (Cu) is an essential element for humans and plants when present in lesser amount, while in excessive amounts it exerts detrimental effects. There subsists a narrow difference amid the indispensable, positive and detrimental concentration of Cu in living system, which substantially alters with Cu speciation, and form of living organisms. Consequently, it is vital to monitor its bioavailability, speciation, exposure levels and routes in the living organisms. The ingestion of Cu-laced food crops is the key source of this heavy metal toxicity in humans. Hence, it is necessary to appraise the biogeochemical behaviour of Cu in soil-plant system with esteem to their quantity and speciation. On the basis of existing research, this appraisal traces a probable connexion midst: Cu levels, sources, chemistry, speciation and bioavailability in the soil. Besides, the functions of protein transporters in soil-plant Cu transport, and the detrimental effect of Cu on morphological, physiological and nutrient uptake in plants has also been discussed in the current manuscript. Mechanisms related to detoxification strategies like antioxidative response and generation of glutathione and phytochelatins to combat Cu-induced toxicity in plants is discussed as well. We also delimits the Cu accretion in food crops and allied health perils from soils encompassing less or high Cu quantity. Finally, an overview of various techniques involved in the reclamation and restoration of Cu-contaminated soils has been provided.


Assuntos
Cobre/metabolismo , Produtos Agrícolas/fisiologia , Poluentes do Solo/metabolismo , Disponibilidade Biológica , Cobre/análise , Cobre/toxicidade , Produtos Agrícolas/metabolismo , Intoxicação por Metais Pesados , Humanos , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
11.
Chemosphere ; 262: 127830, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32763580

RESUMO

Atrazine residue in soil is one of the serious environmental problems and continues to risk ecosystem and human health. To address the environmental behaviors and dissipation of atrazine and better manage the application of atrazine in reality, we comprehensively investigated the adsorption and desorption, migration ability, and vanishing of atrazine in three distinct soils in China including Jiangxi (JX, pH 5.45, TOC 0.54%), Nanjing (NJ, pH 6.15, TOC 2.13%), and Yancheng (YC, pH 8.60, TOC 0.58%) soils. The atrazine adsorptive capacity to the soils was arranged in the order of NJ > YC > JX. The leaching assay with profiles of the soils showed strong migration, suggesting it had a high bioavailability to weeds and potential for underground water contamination. We further investigated the effects of environmental factors such as soil moisture, microbial activity and photolysis on atrazine degradation and showed that the degradation of atrazine in the soil mainly underwent the abiotic process, most likely through hydrolysis and photolysis-mediated mechanisms, and to less extend through soil microbial catabolism. Using HRLC-Q-TOF-MS/MS and by comparing the measured and theoretical m/z values and fragmentation data, ten metabolites comprising eight degraded products and two conjugates were characterized. Atrazine existing in the soils and sprayed coordinately blocked the growth of three common weeds, which prompted us to use the minimal atrazine in practice to control the waste of the pesticide and its impact on the environment. Overall, our work provided an insight into the mechanisms for the degradation of atrazine residues in the soils and contributed to the environmental risk assessment of the pesticide and management in its application control in the crop rotation and safe production.


Assuntos
Atrazina/química , Plantas Daninhas/metabolismo , Poluentes do Solo/metabolismo , Adsorção , Atrazina/metabolismo , Biodegradação Ambiental , Disponibilidade Biológica , China , Ecossistema , Herbicidas/química , Praguicidas/análise , Fotólise , Solo/química , Microbiologia do Solo , Poluentes do Solo/análise , Espectrometria de Massas em Tandem
12.
Chemosphere ; 262: 127815, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32768752

RESUMO

Cadmium (Cd) is a non-essential highly toxic metal and its presence in the environment has been a concern over the years. On the present study we adopt the spiked water exposure scenario to study early Cd contamination across five generations of the model organism Chironomus riparius. Animals were, at the beginning of each generation, submitted to 0, 1, 3.2, 10, 32 and 100 µg/L of Cd. Classical endpoints like total emergence, EmT50, fertility and the integrative fitness measure, population growth rate (PGR), were calculated at each generation. Results could demonstrate that exposure to brief and low Cd concentrations can affect all the measured endpoints and, therefore, initial Cd pollution in previously unpolluted sites can be detected after just five consecutive generations. Importantly, at 100 µg/L of Cd fertility was greatly impaired after three generations. Also, PGR calculation is a sensitive tool for monitoring early pollution of Cd. Yet, no adaptation to Cd over five generations could be observed on the present experimental setup.


Assuntos
Cádmio/metabolismo , Chironomidae/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Cádmio/toxicidade , Chironomidae/crescimento & desenvolvimento , Monitoramento Ambiental , Poluição Ambiental , Fertilidade , Larva/crescimento & desenvolvimento , Poluentes Químicos da Água/análise
13.
Chemosphere ; 262: 127818, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32771707

RESUMO

Yellow mealworms (Tenebrio molitor larvae) are capable of biodegrading polystyrene (PS) and low-density polyethylene (LDPE). This study tested biodegradation of one expanded PS (EPS) with a weight-average molecular weight (Mw) 256.4 kDa and two LDPE foams with respective Mw of 130.6 kDa (PE-1) and 288.7 kDa (PE-2) in T. monitor larvae obtained in Beijing, China. The larvae consumed EPS and both LDPEs over a 60 day. Fourier transform infrared spectroscopy and thermogravimetric analyses of frass confirmed the formation of new oxygen-containing functional groups, as well as a change in physical property and chemical modification, indicating that biodegradation of EPS and LDPE occurred. Gel permeation chromatography analysis confirmed broad depolymerization of EPS and PE-1 (i.e., a decrease in both Mw and a number-average molecular weight (Mn)) but revealed limited extent depolymerization of PE-2 (i.e., increase in Mn and decrease in Mw). For all materials, the size-average molecular weight (Mz) was decreased. Biodegradation and oxidation of EPS and LDPE were confirmed using FTIR and TGA analysis. Depression of gut microbes by the antibiotic gentamicin resulted in significant inhibition of EPS depolymerization but did not stop LDPE depolymerization, resulting in the increase in Mn and revealing that PS biodegradation was gut microbe-dependent but LDPE biodegradation was less dependent or independent of gut microbes. Gut microbial community analysis indicated that, as expected, under different dietary conditions, the intestinal flora significantly shifted to communities associated with biodegradation of EPS and LDPE. The results indicated the complexity and limitation of biodegradation of plastics in plastics-eating T. molitor larvae.


Assuntos
Biodegradação Ambiental , Besouros/metabolismo , Poliestirenos/metabolismo , Tenebrio/metabolismo , Animais , Antibacterianos/metabolismo , Pequim , China , Cromatografia em Gel , Microbioma Gastrointestinal , Gentamicinas , Larva/metabolismo , Plásticos/metabolismo , Polietileno/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Chemosphere ; 262: 127848, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32771708

RESUMO

Honey bees are important pollinators and are subject to numerous stressors, such as changing floral resources, parasites, and agrochemical exposure. Pesticide exposure has been linked to the decline in the global honey bee population. We have limited knowledge of the metabolic pathways and synergistic effects of xenobiotics in bees. Quercetin is one of the most abundant phytochemicals in plants and is therefore abundant in the honey bee diet. Quercetin can upregulate the detoxification system in honey bees; however, it is still unknown to what extent quercetin ingestion can reduce the content of absorbed pesticides. In this study, we investigated the effect of dietary quercetin on the contents of three pesticides in honey bees: imidacloprid (insecticide), tebuconazole (fungicide), and tau-fluvalinate (insecticide and acaricide). Bees were divided into two main groups and fed either quercetin-sucrose paste or only sucrose for 72 h. Thereafter, they were orally exposed to ∼10 ng/bee imidacloprid or contact-exposed to ∼0.9 µg/bee tau-fluvalinate or ∼5.2 µg/bee tebuconazole. After 1 h of oral exposure or 24 h of contact exposure, the bees were anaesthetised with CO2, sacrificed by freezing, and extracted with a validated QuEChERS method. Subsequently, the concentrations of the three pesticides and quercetin in the bees were determined with a triple quadrupole tandem mass spectrometer coupled to an HPLC system. No significant effect on the concentration of tebuconazole or tau-fluvalinate was observed in bees fed quercetin. Intake of quercetin led to a reduction in the concentration of imidacloprid in honey bees. Quercetin-rich plants may be exploited in future beekeeping.


Assuntos
Abelhas/metabolismo , Praguicidas/metabolismo , Quercetina , Acaricidas , Animais , Criação de Abelhas , Dieta , Inseticidas , Neonicotinoides , Nitrilos , Nitrocompostos , Compostos Fitoquímicos , Piretrinas , Xenobióticos
15.
Chemosphere ; 262: 127869, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32771709

RESUMO

Barite (BaSO4) is a component of drilling fluids used in the oil and gas industry and may cause barium (Ba) contamination if it is spilled onto flooded soils. Under anoxic soil conditions and low redox potential, sulfate can be reduced to a more soluble form (sulfide), and Ba can be made available. To design a solution for such environmental issues, a field study was conducted in a Ba-contaminated flooded area in Brazil, in which we induced Ba phytoextraction from the management of the planting density of two intercropped macrophytes. Typha domingensis and Eleocharis acutangula were grown in four initial planting densities: "Ld" (low density: 4 and 32 plants m-2); "Md" (medium density: 8 and 64 plants m-2); "Hd" (high density: 12 and 128 plants m-2); "Vhd" (very high density: 16 and 256 plants m-2). Vhd produced the largest number of plants after 300 days. However, the treatments did not differ in terms of the amount of biomass. The increments in the initial planting density did not increase the Ba concentration in the aerial part. The greatest Ba phytoextraction (aerial part + root) was achieved by Ld treatment, which removed approximately 3 kg of Ba ha-1. Md and Vhd treatments had the highest Ba translocation factors. Because more plants per area did not result in greater Ba phytoextraction, a lower planting density was recommended for the intercropping of T. domingensis and E. acutangula to promote the phytoextraction of barium, due to possible lower implementation costs in contaminated flooded environments.


Assuntos
Biodegradação Ambiental , Poluentes do Solo/metabolismo , Typhaceae/fisiologia , Bário , Sulfato de Bário , Biomassa , Brasil , Eleocharis , Inundações , Solo , Poluentes do Solo/análise
16.
Chemosphere ; 262: 127880, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32777607

RESUMO

BACKGROUND: Bisphenol A (BPA) is a well-known endocrine disruptor that affects male fertility. However, the main biological events through which BPA affects spermatogenesis remain to be identified. METHODS: Adult male mice were treated by feeding with drinking water containing BPA (0.2 µg/ml, 20 µg/ml, 200 µg/ml, respectively) for two months. Testes were collected for protein extraction or for immunohistochemical analysis. Epididymal spermatozoa were collected for sperm quality evaluation and male fertility assay by in vitro fertility (IVF). Serums were collected for detection of testosterone levels. Proteins associated with germ cell proliferation, meiosis, blood-testis barrier, and steroidogenesis production were examined in BPA-treated and control mice testes. CCK8 assay was used to detect the effect of BPA on the proliferation of GC-1 and GC-2 cells. RESULTS: The BPA-treated mice were characterized by decreased sperm quality, serum testosterone levels and, sub-fertile phenotype characterizing with low pregnancy rates and reduced fertilization efficiency. In lower BPA (0.2 µg/ml) treatment, PCNA and PLZF were down-expressed that indicated impaired germ cell proliferation. SYCP3 was down-expressed in BPA-treated mice, but expressions of other proteins associated with meiosis and blood-testis barrier were not significantly altered. CYP11A1 and HSD3B1 were down-expressed in BPA-treated mice that demonstrated reduced steroidogenesis activity. BPA has a concentration-dependent inhibition effect on the proliferation of GC-1 and GC-2 cells. Conclusively, low doses BPA exposure reduced mice sperm quality mainly by impairing germ cell proliferation, leading to reduced male fertility. The study would provide relevant information for investigation on molecular mechanisms and protective strategy on male production.


Assuntos
Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Fenóis/toxicidade , Espermatozoides/fisiologia , Animais , Proliferação de Células/efeitos dos fármacos , Disruptores Endócrinos/metabolismo , Epididimo/efeitos dos fármacos , Feminino , Fertilidade/efeitos dos fármacos , Masculino , Camundongos , Gravidez , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testes de Toxicidade Crônica
17.
Chemosphere ; 262: 127841, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32784060

RESUMO

Environmental pollutants suspected of disrupting the endocrine system are considered etiologic factors in the epidemic of metabolic disorders. As regulation of energy metabolism relies on the integrated action of a large number of hormones, we hypothesized that certain chemicals could trigger changes in glucocorticoid signaling. To this end, we exposed C57Bl6/J female and male mice between 5 and 20 weeks of age to a mixture of 2,3,7,8- tetrachlorodibenzo-p-dioxin (20 pg/kg body weight/day [bw/d]), polychlorobiphenyl 153 (200 ng/kg bw/d), di-[2-ethylhexyl]-phthalate (500 µg/kg bw/d) and bisphenol A (40 µg/kg bw/d). In female mice fed a standard diet (ST), we observed a decrease in plasma levels of leptin as well as a reduced expression of corticoid receptors Nr3c1 and Nr3c2, of leptin and of various canonical genes related to the circadian clock machinery in visceral (VAT) but not subcutaneous (SAT) adipose tissue. However, Nr3c1 and Nr3c2 mRNA levels did not change in high-fat-fed females exposed to pollutants. In ST-fed males, pollutants caused the same decrease of Nr3c1 mRNA levels in VAT observed in ST-fed females but levels of Nr3c2 and other clock-related genes found to be down-regulated in female VAT were enhanced in male SAT and not affected in male VAT. The expression of corticoid receptors was not affected in the livers of both sexes in response to pollutants. In summary, exposure to a mixture of pollutants at doses lower than the no-observed adverse effect levels (NoAELs) resulted in sex-dependent glucocorticoid signaling disturbances and clock-related gene expression modifications in the adipose tissue of ST-fed mice.


Assuntos
Poluentes Ambientais/toxicidade , Glucocorticoides/metabolismo , Tecido Adiposo/metabolismo , Animais , Compostos Benzidrílicos , Peso Corporal , Poluentes Ambientais/metabolismo , Feminino , Expressão Gênica , Leptina/sangue , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenóis , Dibenzodioxinas Policloradas/metabolismo , RNA Mensageiro/metabolismo , Sensibilidade e Especificidade
18.
Chemosphere ; 262: 127831, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32791367

RESUMO

The study was conducted to investigate the influence of the culture pattern on plant uptake and translocation of an organic chemical and the resultant acute response of plants, and to further reveal the interconnection. Plant exposure experiments were performed using a conventional rice seedling (Oryza sativa L. subsp. indica) under two kinds of culture patterns (viz., hydroponics and soil-based culture) with various culture matrices for a period of 7 days. The exposure concentration of lindane was ∼450 µg L-1 in the aqueous-phase matrices, and 200.1-756.0 µg kg-1 in the solid matrices. Lindane accumulation and its distribution in plant tissues were quantified, as well as the tissue biomass. The results showed the accumulation of lindane in all exposure groups were comparatively close over the period, confirming that the soil-bound lindane was scarcely available to plants. Similar trend of lindane uptake and translocation in seedlings was found among the groups under the same kind of cultivation pattern. In the hydroponic groups, lindane was mostly distributed in roots (about 60% at the end of exposure), whereas more lindane was translocated to shoots (approximate 70%) under the soil-based culture pattern. Allometric analysis demonstrated that the tissue part (root or shoot) with more lindane accumulation had a relatively higher growth rate over 7 days. Correspondingly, biomass allocation presented a slight trend of mutual proximity to lindane distribution. It was inferred that plants altered their allometric growth pattern to realize biomass re-allocation in response to the short-term lindane exposure, which could be considered as a plant defense strategy.


Assuntos
Hexaclorocicloexano/metabolismo , Oryza/metabolismo , Poluentes do Solo/metabolismo , Transporte Biológico , Biomassa , Hidroponia , Oryza/crescimento & desenvolvimento , Raízes de Plantas/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Solo , Poluentes do Solo/análise
19.
Chemosphere ; 262: 127865, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32791369

RESUMO

Chromium is a toxic heavy metal. Plants, animals and human metabolic processes are disturbed due to higher levels of chromium. PGPR are involved in seed germination, growth improvement, metabolic process and in most of the physiological processes of plants. Press mud in soil provides substrate to the microbes. PGPR can convert the more toxic form of Cr (VI) into less toxic form Cr (III). This study was conducted to find out the reduction potential of pre-isolated rhizobacteria and their role in strengthening of plant growth and physiological attributes. Soil collected from the research area was spiked with 20 mg kg-1 of Cr (VI) by using potassium dichromate (K2Cr2O7) salt before sowing. Results revealed that Cr (VI) significantly suppressed the shoot length, root length and photosynthetic rate of okra up to 19, 37 and 31%, respectively. However, inoculation decreases the uptake of Cr (VI) in root and shoot up to 37 and 31% and by press mud 33 and 20%, respectively. Combined application of inoculation and press mud significantly recovered the negative impact of chromium and plant growth was almost at par compared with contaminated treatment without inoculation.


Assuntos
Abelmoschus/crescimento & desenvolvimento , Cromo/análise , Poluentes do Solo/análise , Abelmoschus/metabolismo , Fotossíntese , Desenvolvimento Vegetal , Solo , Microbiologia do Solo
20.
Chemosphere ; 262: 128388, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182095

RESUMO

Arbitrary use of insecticides in agricultural practices cause severe environmental hazard that adversely affects the growth and productivity of edible crops. Considering theses, the aim of the present study was to evaluate the toxicological potential of two neonicotinoid insecticides, imidacloprid (IMID) and thiamethoxam (THIA) using chickpea as a test crop. Application of insecticides at three varying doses revealed a gradual decrease in biological performance of chickpea plants which however, varied noticeably among insecticides and their doses. Significant (P ≤ 0.05) decline in germination efficiency, length of plant organs under in vitro condition was observed in a dose related manner. Among insecticides, 300 µgIMIDkg-1 (3X dose) maximally and significantly (P ≤ 0.05) inhibited germination efficiency, vigor index, length, dry matter accumulation, photosynthetic pigment formation, nodule volume and mass, nutrient uptake, grain yield and protein over untreated control. In contrast, 75 µgTHIAkg-1 (3X dose) considerably declined the leghaemoglobin content, shoot phosphorus and root nitrogen. Enhanced expression of stress biomarkers including proline, malondialdehyde (MDA), and antioxidant defence enzymes was noticed in the presence of insecticides. For instance, at 3X IMID, shoot proline, MDA, ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and peroxidase (POD) were increased significantly (P ≤ 0.05) by 66%, 81%, 36% and 35%, respectively. Additionally, electrolyte leakage was maximally (77%) increased at 3X dose of IMID, whereas, H2O2 in foliage was maximally accumulated (0.0156 µ moles min-1 g-1 fw) at 3X dose of THIA which was 58% greater than untreated foliage. A clear distortion/damage in tip and surface of roots and ultrastructural deformation in xylem and phloem of plant tissues as indication of insecticidal phytotoxicity was observed under scanning electron microscope (SEM). For oxidative stress and cytotoxicity assessment, root tips were stained with a combination of acridine orange and propidium iodide, and Evan blue dyes and examined. Confocal laser scanning microscopic (CLSM) images of roots revealed a 10-fold and 13.5-fold increase in red and blue fluorescence when 3X IMID treated roots were assessed quantitatively. Conclusively, the present investigation recommends that a careful and protected approach should be adopted before the application of insecticides in agricultural ecosystems.


Assuntos
Cicer/fisiologia , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Cicer/enzimologia , Ecossistema , Germinação , Peróxido de Hidrogênio/metabolismo , Inseticidas/metabolismo , Malondialdeído/metabolismo , Nitrocompostos , Estresse Oxidativo , Peroxidase , Fotossíntese
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