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1.
Mol Pharm ; 18(1): 285-304, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33390018

RESUMO

Boron neutron capture therapy (BNCT) is a noninvasive binary therapeutic modality applicable to the treatment of cancers. While BNCT offers a tumor-targeting selectivity that is difficult to match by other means, the last obstacles preventing the full harness of this potential come in the form of the suboptimal boron delivery strategies presently used in the clinics. To address these challenges, we have developed delivery agents that target the glucose transporter GLUT1. Here, we present the chemical synthesis of a number of ortho-carboranylmethyl-substituted glucoconjugates and the biological assessment of all positional isomers. Altogether, the study provides protocols for the synthesis and structural characterization of such glucoconjugates and insights into their essential properties, for example, cytotoxicity, GLUT1-affinity, metabolism, and boron delivery capacity. In addition to solidifying the biochemical foundations of a successful GLUT1-targeting approach to BNCT, we identify the most promising modification sites in d-glucose, which are critical in order to further develop this strategy toward clinical use.


Assuntos
Boro/administração & dosagem , Boro/química , Neoplasias Encefálicas/radioterapia , Transportador de Glucose Tipo 1/metabolismo , Compostos de Boro/administração & dosagem , Compostos de Boro/química , Terapia por Captura de Nêutron de Boro/métodos , Linhagem Celular Tumoral , Glucose/metabolismo , Humanos
2.
Plant J ; 97(2): 306-320, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30288820

RESUMO

Calamine accessions of the zinc/cadmium/nickel hyperaccumulator, Noccaea caerulescens, exhibit striking variation in foliar cadmium accumulation in nature. The Ganges accession (GA) from Southern France displays foliar cadmium hyperaccumulation (>1000 µg g-1 DW), whereas the accession La Calamine (LC) from Belgium, with similar local soil metal composition, does not (<100 µg g-1 DW). All calamine accessions are cadmium hypertolerant. To find out the differences between LC and GA in their basic adaptation mechanisms, we bypassed the cadmium excluding phenotype of LC by exposing the plants to 50 µm cadmium in hydroponics, achieving equal cadmium accumulation in the shoots. The iron content increased in the roots of both accessions. GA exhibited significant decreases in manganese and zinc contents in the roots and shoots, approaching those in LC. Altogether 702 genes responded differently to cadmium exposure between the accessions, 157 and 545 in the roots and shoots, respectively. Cadmium-exposed LC showed a stress response and had decreased levels of a wide range of photosynthesis-related transcripts. GA showed less changes, mainly exhibiting an iron deficiency-like response. This included increased expression of genes encoding five iron deficiency-regulated bHLH transcription factors, ferric reduction oxidase FRO2, iron transporters IRT1 and OPT3, and nicotianamine synthase NAS1, and decreased expression of genes encoding ferritins and NEET (a NEET family iron-sulfur protein), which is possibly involved in iron transfer, distribution and/or management. The function of the IRT1 gene in the accessions was compared. We conclude that the major difference between the two accessions is in the way they cope with iron under cadmium exposure.


Assuntos
Brassicaceae/genética , Cádmio/metabolismo , Ferro/metabolismo , Transcriptoma , Brassicaceae/fisiologia , Produtos Agrícolas , Homeostase , Hidroponia , Deficiências de Ferro , Metais/metabolismo , Fotossíntese/genética , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , RNA-Seq , Thlaspi/genética , Thlaspi/fisiologia , Zinco/metabolismo
3.
Mol Pharm ; 17(10): 3885-3899, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-32787269

RESUMO

Boron neutron capture therapy (BNCT) for cancer is on the rise worldwide due to recent developments of in-hospital neutron accelerators which are expected to revolutionize patient treatments. There is an urgent need for improved boron delivery agents, and herein we have focused on studying the biochemical foundations upon which a successful GLUT1-targeting strategy to BNCT could be based. By combining synthesis and molecular modeling with affinity and cytotoxicity studies, we unravel the mechanisms behind the considerable potential of appropriately designed glucoconjugates as boron delivery agents for BNCT. In addition to addressing the biochemical premises of the approach in detail, we report on a hit glucoconjugate which displays good cytocompatibility, aqueous solubility, high transporter affinity, and, crucially, an exceptional boron delivery capacity in the in vitro assessment thereby pointing toward the significant potential embedded in this approach.


Assuntos
Terapia por Captura de Nêutron de Boro/métodos , Boro/administração & dosagem , Portadores de Fármacos/efeitos da radiação , Glucose/efeitos da radiação , Isótopos/administração & dosagem , Neoplasias/radioterapia , Boro/farmacocinética , Linhagem Celular Tumoral , Portadores de Fármacos/síntese química , Portadores de Fármacos/farmacocinética , Liberação Controlada de Fármacos/efeitos da radiação , Glucose/análogos & derivados , Glucose/síntese química , Glucose/farmacocinética , Transportador de Glucose Tipo 1/metabolismo , Humanos , Isótopos/farmacocinética , Simulação de Acoplamento Molecular
4.
BMC Musculoskelet Disord ; 21(1): 610, 2020 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-32919463

RESUMO

BACKGROUND: Modern metal-on-metal (MOM) arthroplasties were performed for over a decade before alarming reports of adverse metal reactions dramatically reduced their use. Failures are seen more often with high-wearing implants, but also well-positioned components with more favourable wear patterns can cause problems. There are no specific clinical indicators that could help us to predict the prognosis of these implants. For this reason, we still need more information on the effect of underlying factors that contribute to this process. METHODS: In this prospective cohort study, we investigated how cup orientation and type of pseudotumour determined by the Hart classification effect the distribution of metals in blood, synovial fluid and tissues surrounding the metal-on-metal hip prosthesis in revision surgery patients. One thousand two hundred twenty-nine metal-on-metal hip patients were screened and of those, 60 patients that had a revision surgery due to adverse metal reaction were included. Whole blood, synovial fluid and synovial/pseudotumour tissue samples were analysed for metal ion concentrations (Co, Cr, Mo and Ti). RESULTS: The lowest metal concentrations were found when both cup anteversion and inclination were optimal, and the highest when both were suboptimal. Suboptimal anteversion alone raised Cr-ion concentrations more than suboptimal inclination. The concentrations of metals in blood, synovial fluid or synovial soft tissue were the same in patients with and without a pseudotumour, but the relative transfer percentage of cobalt from synovial fluid to blood was higher in patients with a pseudotumour. CONCLUSIONS: The implant orientation alone does not explain the metal concentrations found in tissues or distribution of metals between different tissues. The accumulation of metals in periprosthetic soft tissues increase the total metal load, and in the presence of a pseudotumour this is reflected in the transfer ratio of Co from synovial fluid to the blood. The total metal load of the pseudotumour tissue should be defined in future studies to determine if this will provide new insights for clinical practice.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Próteses Articulares Metal-Metal , Artroplastia de Quadril/efeitos adversos , Cromo , Cobalto , Prótese de Quadril/efeitos adversos , Humanos , Próteses Articulares Metal-Metal/efeitos adversos , Estudos Prospectivos , Desenho de Prótese , Falha de Prótese , Líquido Sinovial
5.
Biochem J ; 473(10): 1433-41, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-27001865

RESUMO

Polyamine metabolism is an attractive anticancer drug target, since polyamines are absolutely required for cellular proliferation, and increased levels of polyamines and their biosynthetic enzyme ornithine decarboxylase (ODC) are associated with cancer. Triethylenetetramine (TETA) is a charge-deficient isosteric analogue of the polyamine spermidine (Spd) and a Cu(II)-chelating compound used for the treatment of Wilson's disease, and it has been implicated as a potential anticancer therapeutic drug. In the present study, we studied the effects of TETA in comparison with two other Cu(II)-chelators, D-penicillamine (PA) and tetrathiomolybdate (TTM), on polyamine metabolism in DU145 prostate carcinoma, MCF-7 breast carcinoma and JEG-3 choriocarcinoma cells. TETA induced antizyme, down-regulated ODC and inhibited [(14)C] Spd uptake. Moreover, it completely prevented α-difluoromethylornithine (DFMO)-induced increase in [(14)C] Spd uptake, and inhibited [(14)C] putrescine (Put) uptake and ODC activity in vivo Seven-day treatment of DU145 cells with TETA caused growth cessation by reducing intracellular polyamine levels and suppressing the formation of hypusinated eukaryotic translation initiation factor 5A (eIF5A). TETA or its N-acetylated metabolites also inhibited spermine (Spm), diamine and semicarbazide-sensitive amine oxidases and decreased the level of intracellular reactive oxygen species. Moreover, TETA inhibited the utilization of Put as energy source via the tricarboxylic acid (TCA) cycle, as indicated by decreased production of (14)CO2 from [(14)C] Put. These results indicate that TETA attacks multiple proven anticancer drug targets not attributed to copper chelation, which warrants further studies to reveal its potential in cancer chemoprevention and cure.


Assuntos
Proliferação de Células/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Poliaminas/metabolismo , Trientina/farmacologia , Amina Oxidase (contendo Cobre) , Linhagem Celular Tumoral , Eflornitina/metabolismo , Feminino , Humanos , Células MCF-7 , Masculino , Molibdênio/farmacologia , Penicilamina/metabolismo , Putrescina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Espermina/metabolismo
6.
Bone Joint Res ; 13(4): 149-156, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38569600

RESUMO

Aims: Metal particles detached from metal-on-metal hip prostheses (MoM-THA) have been shown to cause inflammation and destruction of tissues. To further explore this, we investigated the histopathology (aseptic lymphocyte-dominated vasculitis-associated lesions (ALVAL) score) and metal concentrations of the periprosthetic tissues obtained from patients who underwent revision knee arthroplasty. We also aimed to investigate whether accumulated metal debris was associated with ALVAL-type reactions in the synovium. Methods: Periprosthetic metal concentrations in the synovia and histopathological samples were analyzed from 230 patients from our institution from October 2016 to December 2019. An ordinal regression model was calculated to investigate the effect of the accumulated metals on the histopathological reaction of the synovia. Results: Median metal concentrations were as follows: cobalt: 0.69 µg/g (interquartile range (IQR) 0.10 to 6.10); chromium: 1.1 µg/g (IQR 0.27 to 4.10); and titanium: 1.6 µg/g (IQR 0.90 to 4.07). Moderate ALVAL scores were found in 30% (n = 39) of the revised knees. There were ten patients with an ALVAL score of 6 or more who were revised for suspected periprosthetic joint infection (PJI), aseptic loosening, or osteolysis. R2 varied between 0.269 and 0.369 for the ordinal regression models. The most important variables were model type, indication for revision, and cobalt and chromium in the ordinal regression models. Conclusion: We found that metal particles released from the knee prosthesis can accumulate in the periprosthetic tissues. Several patients revised for suspected culture-negative PJI had features of an ALVAL reaction, which is a novel finding. Therefore, ALVAL-type reactions can also be found around knee prostheses, but they are mostly mild and less common than those found around metal-on-metal prostheses.

7.
J Cell Mol Med ; 16(11): 2754-67, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22805236

RESUMO

Alzheimer's disease (AD) and cerebral ischaemia share similar features in terms of altered amyloid precursor protein (APP) processing and ß-amyloid (Aß) accumulation. We have previously shown that Aß and calcium deposition, and ß-secretase activity, are robustly increased in the ipsilateral thalamus after transient middle cerebral artery occlusion (MCAO) in rats. Here, we investigated whether the non-selective calcium channel blocker bepridil, which also inhibits ß-secretase cleavage of APP, affects thalamic accumulation of Aß and calcium and in turn influences functional recovery in rats subjected to MCAO. A 27-day bepridil treatment (50 mg/kg, p.o.) initiated 2 days after MCAO significantly decreased the levels of soluble Aß40, Aß42 and calcium in the ipsilateral thalamus, as compared with vehicle-treated MCAO rats. Expression of seladin-1/DHCR24 protein, which is a potential protective factor against neuronal damage, was decreased at both mRNA and protein levels in the ipsilateral thalamus of MCAO rats. Conversely, bepridil treatment restored seladin-1/DHCR24 expression in the ipsilateral thalamus. Bepridil treatment did not significantly affect heme oxygenase-1- or NAD(P)H quinone oxidoreductase-1-mediated oxidative stress or inflammatory responses in the ipsilateral thalamus of MCAO rats. Finally, bepridil treatment mitigated MCAO-induced alterations in APP processing in the ipsilateral thalamus and improved contralateral forelimb use in MCAO rats. These findings suggest that bepridil is a plausible therapeutic candidate in AD or stroke owing to its multifunctional role in key cellular events that are relevant for the pathogenesis of these diseases.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Bepridil/farmacologia , Cálcio/metabolismo , Infarto da Artéria Cerebral Média/tratamento farmacológico , Tálamo/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo L/genética , Heme Oxigenase-1/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Masculino , NAD(P)H Desidrogenase (Quinona)/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Ratos , Ratos Wistar , Tálamo/efeitos dos fármacos
8.
Amino Acids ; 42(2-3): 461-71, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21814793

RESUMO

Depletion of pancreatic intracellular polyamine pools has been observed in acute pancreatitis both in the animal models and in humans. In this study, the wild-type mice, polyamine catabolic enzyme spermidine/spermine N(1)-acetyltransferase overexpressing (SSAT mice) and SSAT-deficient mice were used to characterize the new zinc-induced acute pancreatitis mouse model and study the role of polyamines and polyamine catabolism in this model. Intraperitoneal zinc injection induced acute necrotizing pancreatitis in wild-type mice as well as in SSAT-overexpressing and SSAT-deficient mice. Serum α-amylase activity was significantly increased in all zinc-treated mice compared with the untreated controls. However, the α-amylase activities in SSAT mice were constantly lower than those in the other groups. Histopathological examination of pancreatic tissue revealed edema, acinar cell necrosis and necrotizing inflammation, typical for acute pancreatitis. Compared with the other zinc-treated mice less damage according to the histopathological analysis was observed in the pancreatic tissue of SSAT mice. Levels of intracellular spermidine, and occasionally spermine, were significantly decreased in pancreases of all zinc-treated animals and SSAT enzyme activity was enhanced both in wild-type and SSAT mice. Interestingly, a spermine analog, N(1), N(11)-diethylnorspermine (DENSpm), enhanced the proliferation of pancreatic cells and reduced the severity of zinc-induced pancreatitis in wild-type mice. The results show that in mice a single intraperitoneal zinc injection causes acute necrotizing pancreatitis accompanied by decrease of intracellular polyamine pools. The study supports the important role of polyamines for the integrity and function of the pancreas. In addition, the study suggests that whole body overexpression of SSAT obtained in SSAT mice reduces inflammatory pancreatic cell injury.


Assuntos
Acetiltransferases/metabolismo , Pancreatite/induzido quimicamente , Espermina/análogos & derivados , Zinco/toxicidade , Acetiltransferases/genética , Animais , Imuno-Histoquímica , Camundongos , Camundongos Transgênicos , Índice de Gravidade de Doença , Espermina/farmacologia
9.
Molecules ; 17(9): 10928-45, 2012 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-22971579

RESUMO

Aminobisphosphonates, e.g., alendronate and neridronate, are a well known class of molecules used as drugs for various bone diseases. Although these molecules have been available for decades, a detailed understanding of their most important physicochemical properties under comparable conditions is lacking. In this study, ten aminobisphosphonates, H(2)N(CH2)(n)C(OH)[P(O)(OH)(2)](2) in which n = 2-5, 7-11 and 15 have been synthesized. Their aqueous solubility as a function of temperature and pH, pK(a-) values, thermal stability, IR absorptions, and NMR spectral data for both liquid (1)H, (13)C, (31)P-NMR and solid state(13)C, (15)N and (31)P-CPMAS NMR) were determined.


Assuntos
Alendronato/química , Difosfonatos/química , Difosfonatos/síntese química , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Solubilidade , Temperatura , Água/química
10.
J Trace Elem Med Biol ; 73: 127042, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35905605

RESUMO

INTRODUCTION: All animals, including humans, are exposed to heavy metals which are known to accumulate in different tissues, especially in bone. During pregnancy, the maternal bone turnover is increased and the metals in the mother's body can be mobilized into the bloodstream. Heavy metals in maternal blood are known to pass through the placenta to the fetal blood and finally, deposited to bone tissue. However, there are no studies on the concentration of metals in the fetal solid tissues and until now, the rate of metal transfer from mother to fetus is not exactly known. MATERIALS AND METHODS: Samples of the blood, liver, placenta, and three different bones were collected from 17 pregnant ewes and their 27 fetuses. The animals had no known exposure to heavy metals. The concentrations of Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, Sb, Sn, Sr, Te, Ti, Tl, V, and Zn were analyzed using ICP-MS. RESULTS AND DISCUSSION: The concentration of Sb, Sn, Te, and Tl were under the detection limit in all the samples. The other metals were found in all maternal and fetal tissues, suggesting that all detectable metals cross the placenta. Blood concentrations were low compared to solid tissue concentrations. The concentrations of essential elements varied between maternal and fetal tissues, which could be explained by biological differences. The differences in concentrations of non-essential elements between the ewe and fetuses were smaller. The most significant differences were between maternal and fetal concentrations of Ba and Sr, which is at least partly explained by the mineralization degree of the bone. CONCLUSION: Heavy metals accumulate in fetal solid tissues in sheep that are not directly exposed to heavy metals. Because of the differences in anatomy between human and sheep placenta, the accumulation in the tissue of human fetuses should be extrapolated cautiously. However, there might be some clinical relevance for fertile aged women who are exposed to heavy metals, such as women who work in the metal industry or who have undergone joint replacement surgery.


Assuntos
Mercúrio , Metais Pesados , Oligoelementos , Idoso , Animais , Feminino , Sangue Fetal , Humanos , Placenta , Gravidez , Ovinos
11.
Sci Total Environ ; 809: 152209, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-34883169

RESUMO

Soil and water contaminations are caused by rare earth elements (REEs) due to mining and industrial activities, that threaten the ecosystem and human health. Therefore, phytoremediation methods need to be developed to overcome this problem. To date, little research has been conducted concerning the phytoremediation potential of Salix for REEs. In this study, two Salix species (Salix myrsinifolia and Salix schwerinii) and two Salix cultivars (Klara and Karin) were hydroponically exposed to different concentrations of six-REE for 4 weeks. The treatments were: T1 (Control: tap water), T2 (La: 50 mg/L) and T3 (La 11.50 + Y 11 + Nd 10.50 + Dy 10 + Ce 12 and Tb 11.50 in mg L-1). The effects of the REE on Salix growth indicators (height, biomass, shoot diameter and root length), concentrations of REE in the produced biomass, and accumulation of REE in different parts of the Salix (stem, root, and leaf) tissues, were determined. In addition, the retention of REE in ashes following Salix combustion (800 and 1000 °C) was determined. The result indicates that with La and REE exposure, the height growth, dry biomass, shoot diameter and root length of all Salix remained equivalent to the control treatment excluding Klara, which displayed relatively higher growth in all parameters. Further, among the REE studied, the highest La concentration (8404 µg g-1 DW) and La accumulation (10,548 µg plant-1) were observed in Karin and Klara root respectively. Translocations and bioconcentration factors were discovered at <1 for all Salix, which indicates their phytostabilization potential. The total REE concentrations in bottom ashes varied between 7 and 8% with retention rates between 85 and 89%. This study demonstrates that Salix are suitable candidates for REE phytostabilization and the remediation of wastewater sites to limit metals percolating to the water layers in the ecosystem.


Assuntos
Metais Terras Raras , Salix , Poluentes do Solo , Biodegradação Ambiental , Ecossistema , Humanos , Poluentes do Solo/análise
12.
Planta ; 233(6): 1173-84, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21327818

RESUMO

Stress tolerance is currently one of the major research topics in plant biology because of the challenges posed by changing climate and increasing demand to grow crop plants in marginal soils. Increased Zn tolerance and accumulation has been reported in tobacco expressing the glyoxalase 1-encoding gene from Brassica juncea. Previous studies in our laboratory showed some Zn tolerance-correlated differences in the levels of glyoxalase 1-like protein among accessions of Zn hyperaccumulator Thlaspi caerulescens. We have now isolated the corresponding gene (named here TcGLX1), including ca. 570 bp of core and proximal promoter region. The predicted protein contains three glyoxalase 1 motifs and several putative sites for post-translational modification. In silico analysis predicted a number of cis-acting elements related to stress. The expression of TcGLX1 was not responsive to Zn. There was no correlation between the levels of TcGLX1 expression and the degrees of Zn tolerance or accumulation among T. caerulescens accessions nor was there co-segregation of TcGLX1 expression with Zn tolerance or Zn accumulation among F3 lines derived from crosses between plants from accessions with contrasting phenotypes for these properties. No phenotype was observed in an A. thaliana T-DNA insertion line for the closest A. thaliana homolog of TcGLX1, ATGLX1. These results suggest that glyoxalase 1 or at least the particular isoform studied here is not a major determinant of Zn tolerance in the Zn hyperaccumulator plant T. caerulescens. In addition, ATGLX1 is not essential for normal Zn tolerance in the non-tolerant, non-accumulator plant A. thaliana. Possible explanations for the apparent discrepancy between this and previous studies are discussed.


Assuntos
Lactoilglutationa Liase/genética , Metais Pesados/metabolismo , Proteínas de Plantas/genética , Thlaspi/enzimologia , Thlaspi/genética , Adaptação Fisiológica/genética , Sequência de Bases , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Lactoilglutationa Liase/metabolismo , Dados de Sequência Molecular , Proteínas de Plantas/biossíntese , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas , Análise de Sequência de Proteína , Estresse Fisiológico/genética , Thlaspi/metabolismo , Zinco/metabolismo
13.
Insects ; 12(10)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34680656

RESUMO

Insects vary in the degree of their adaptability to environmental contamination. Determining the responses with phenotypic plasticity in ecologically important species in polluted environments will ease further conservation and control actions. Here, we investigated morphological characteristics such as body size, body mass, and color of the common wasp Vespula vulgaris in an industrially polluted environment, considering different levels of metal pollution, and we studied the localization of contaminants in the guts of wasps. We revealed some differences in morphological characteristics and melanization of wasps collected in habitats with high, moderate, and low levels of pollution. The results indicated that V. vulgaris from highly polluted environments had reduced melanin pigmentation on the face but increased melanin pigmentation on the 2nd tergite of the abdomen. In addition, with transmission electron microscopy (TEM) and energy dispersive X-ray analysis (EDX), we found metal particles from the midgut of wasps originating from the polluted environment. Most of the particles were encapsulated with melanin pigment. This finding confirmed that in wasps, ingested metal particles are accumulated in guts and covered by melanin layers. Our data suggest that wasps can tolerate metal contamination but respond phenotypically with modification of their size, coloration, and probably with the directions of the melanin investments (immunity or coloration). Thus, in industrially polluted areas, wasps might probably survive by engaging phenotypic plasticity with no significant or visible impact on the population.

14.
Sci Total Environ ; 753: 142013, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32890867

RESUMO

Companies in the wood industry are constantly developing their outdoor products. The possibility of using bio-based chemicals as an alternative to traditional wood preservatives-regulated in Europe by The Biocidal Products Regulation No 528/2012-has been considered, but chemical leaching from the wood decreases its effectiveness and may negatively affect the environment. This study aims to compare the effectiveness of bio-based chemicals with potential use in wood preservation to commercially available preservatives, to investigate their fixation to wood and their ecotoxicity and to quantify the potentially toxic elements leached from the wood. Pyrolysis distillates of tree bark, organic acids found in distillates, Colatan GT10 tannin extract and log soaking liquid as a hardwood veneer process residue were tested and compared with commercial pine oil and a copper-based wood preservative. In the wood decay test of impregnated pine sapwood specimens, Colatan GT10 extract performed as well as the commercial wood preservatives. The same decay trial with leached specimens significantly reduced the performance of the bio-based chemicals. The results of the ecotoxicity test with photoluminescent Aliivibrio fischeri bacteria showed that many bio-based chemicals with potential use in wood preservation have markedly lower ecotoxicity than commercially available wood preservatives, but the ecotoxicity of some bio-based chemicals is higher, as in the case of some of the pyrolysis distillates. The wood preservation efficiency and the ecotoxicity of the studied chemicals had a poor correlation, implying that other factors besides treatment agent toxicity play a role in deterring fungal growth on treated wood. The amount of elemental toxins in the leachates was low. These results emphasize the importance of the chemical ecotoxicity of bio-based preservative compounds, as their detrimental effect on the environment can be higher than that of the traditional preservatives unless effectively linked to wood to prevent leaching.


Assuntos
Pinus , Madeira , Cobre/análise , Cobre/toxicidade , Europa (Continente) , Fungos , Madeira/química
15.
Artigo em Inglês | MEDLINE | ID: mdl-34281070

RESUMO

Sewage sludge contains a significant amount of phosphorus (P), which could be recycled to address the global demand for this non-renewable, important plant nutrient. The P in sludge can be solubilized and recovered so that it can be recycled when needed. This study investigated the P solubilization from sewage sludge using Acidithiobacillus thiooxidans and Acidithiobacillus ferrooxidans. The experiment was conducted by mixing 10 mL of sewage sludge with 90 mL of different water/liquid medium/inoculum and incubated at 30 °C. The experiment was conducted in three semi-continuous phases by replacing 10% of the mixed incubated medium with fresh sewage sludge. In addition, 10 g/L elemental sulfur (S) was supplemented into the medium in the third phase. The pH of the A. thiooxidans and A. ferrooxidans treated sludge solutions was between 2.2 and 6.3 until day 42. In phase 3, after supplementing with S, the pH of A. thiooxidans treated sludge was reduced to 0.9, which solubilized and extracted 92% of P. We found that acidithiobacilli supplemented with S can be used to treat sludge, i.e., achieve hygienization, removal of heavy metals, and solubilization and recovery of P.


Assuntos
Acidithiobacillus , Metais Pesados , Concentração de Íons de Hidrogênio , Fósforo , Esgotos
16.
Mar Pollut Bull ; 173(Pt B): 113103, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34741928

RESUMO

Effects of household post-consumer plastics and tyre rubber on a Baltic Sea copepod Limnocalanus macrurus were assessed. Fragments of commercial recycled low-density polyethylene vegetable bags and rubber originating from recycled car tyres were incubated in seawater, and the copepods were exposed to the filtrate of the water. L. macrurus experienced erratic swimming behaviour and increased mortality in the filtrate of unwashed vegetable bags, containing elevated concentrations of alcohols, organic acids and copper. Responses of the antioxidant defence system (ADS) were recorded in copepods exposed to rubber treatments containing high concentrations of zinc. Significant responses in the ADS enzymes indicate that reactive oxygen species (ROS) formation was exceeding the detoxification capacity of the ADS which may further lead to prolonged state of oxidative stress. Observed effects of exposure on the biochemical level coincide with impaired swimming activity of the copepods, indicating possible irreversible cellular responses leading to behavioural changes and mortality.


Assuntos
Copépodes , Poluentes Químicos da Água , Animais , Estresse Oxidativo , Plásticos , Borracha , Água do Mar , Poluentes Químicos da Água/toxicidade
17.
J Hazard Mater ; 400: 123315, 2020 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-32947715

RESUMO

This study assesses the potential of thermal processing for detoxification of wood-combustion ashes that contain high levels of Cr and Cd. Thermal treatment (1000 °C) of bottom ash and fly ash in an oxidising gas (air) atmosphere resulted in: low volatilisation of Cd and most other heavy metals, oxidation of Cr in the ashes to Cr (VI), and, in the case of the fly ash, significantly increased leaching of Cr and Mo. Thermal treatment in a nitrogen atmosphere resulted in local reducing conditions due to oxidation of ash-derived carbon to CO (g). Thermal treatments in this atmosphere and in a reducing atmosphere consisting of 10 % H2 and the balance N2 detoxified the ashes in at least two ways: (i) by substantially removing Cd, Pb, Bi, Tl, and, in the case of the fly ash, Zn from the ashes by volatilisation; and (ii) by thermal reduction of Cr (VI) in the ashes. There was at least a 100-fold reduction in the leaching of total Cr from both the bottom ash and the fly ash following the thermal treatments in reducing conditions. Chromium only leached from the detoxified bottom ash to a significant extent in acidic conditions (pH < 4).

18.
Environ Sci Pollut Res Int ; 27(23): 29031-29042, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32424749

RESUMO

We investigated the common wasp, Vespula vulgaris as a bioindicator and biomonitor of metals in the industrial area. Using traps, we collected 257 yellowjackets along a pollution gradient in the Harjavalta Cu-Ni smelter in Southwest Finland. Our method detected metal elements such as arsenic (As), cobalt (Co), copper (Cu), iron (Fe), nickel (Ni), lead (Pb), zinc (Zn), and mercury (Hg) in wasps. The data analyses revealed V. vulgaris can be a proper indicator for As, Cd, Co, Cu, Ni, and Pb, rather than for Fe and Zn contamination. Body burdens of As, Cd, Co, Cu, Ni, and Pb decreased with an increase in distance from smelter. Enrichment factor (EF) followed the pattern Pb ˃ Cd ˃ As ˃ Co ˃ Cu ˃ Ni. The highest bioaccumulation (BAF) values were revealed for Cd (5.9) and the lowest for Pb (0.1). Specially designed software (WaspFacer) allowed revealing body burdens of As, Cd, Co, Cu, Ni, and Pb to be associated with rather smaller than more asymmetric facial colour markings in yellowjackets. These results add to the body of literature on how heavy metal contaminants can have tangible phenotypic effects on insects and open future opportunities for using wasps as indicators of metal pollution.


Assuntos
Mercúrio , Metais Pesados/análise , Vespas , Animais , Biomarcadores Ambientais , Monitoramento Ambiental , Finlândia
19.
Sci Total Environ ; 710: 136272, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31926411

RESUMO

Airborne particles may effect on indoor air quality in schools. One significant particle source is outdoor dust and soil transported indoors on people's shoes, which may be resuspended, and further inhaled by pupils and teachers. In many Finnish schools, shoes are taken off by coat racks near the classrooms (shoe schools). The new course of action is to take shoes off right when entering the building (sock schools). In this study, particle mass and number concentrations, together with chemical composition of the dust were investigated in sock and shoe schools. According to results, PM10 and PM15 concentrations in corridors were significantly higher in shoe schools compared to sock schools (p < 0.05). The shoeless course did not affect on the particle number concentrations, but the increases in the number concentrations originated from diners. The elemental concentrations (Li, Al, Si, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Ba, Pb) in settled dust were also higher in shoe schools compared to sock schools, and the Zn concentrations differed significantly (p < 0.05). In conclusion, this study showed that by taking the shoes off when entering the school building you can enhance the indoor air quality by reducing the particle mass concentrations.


Assuntos
Poeira , Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Monitoramento Ambiental , Tamanho da Partícula , Instituições Acadêmicas
20.
J Hazard Mater ; 381: 120871, 2020 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-31374372

RESUMO

Clay-cellulose biocomposite (CCB) was synthesized in the present study. Spin and pressure-induced heating was applied to aggregate exfoliated clay tubules and cellulose using polyethylene glycol as an intermediate. The synthesized CCB was modified in the presence of NaOH at high temperature to obtain negative surface charge on the adsorbent. Physico-chemical properties of CCB were evaluated using different characterization techniques including Fourier transform infrared (FT-IR) and X-ray photoelectron (XPS) spectroscopy. The efficiency of the synthesized biocomposite for Pb(II) and Cd(II) removal from water was studied via laboratory scale experiments. The adsorption kinetics of Pb(II) and Cd(II) onto CCB was well described by the pseudo-second-order kinetic model. The maximum Langmuir adsorption capacity of CCB was found to be 389.78 and 115.96 mg g-1 for Pb(II) and Cd(II), respectively. Fixed-bed column studies were conducted for the adsorption system to compare the adsorption performance of CCB in continuous mode.


Assuntos
Cádmio/química , Celulose/química , Argila/química , Chumbo/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Cinética
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