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Hyperglycemia is a potent risk factor for the development and progression of diabetes-induced nephropathy. Dendropanoxide (DPx) is a natural compound isolated from Dendropanax morbifera (Araliaceae) that exerts various biological effects. However, the role of DPx in hyperglycemia-induced renal tubular cell injury remains unclear. The present study explored the protective mechanism of DPx on high glucose (HG)-induced cytotoxicity in kidney tubular epithelial NRK-52E cells. The cells were cultured with normal glucose (5.6 mM), HG (30 mM), HG + metformin (10 µM), or HG + DPx (10 µM) for 48 h, and cell cycle and apoptosis were analyzed. Malondialdehyde (MDA), advanced glycation end products (AGEs), and reactive oxygen species (ROS) were measured. Protein-based nephrotoxicity biomarkers were measured in both the culture media and cell lysates. MDA and AGEs were significantly increased in NRK-52E cells cultured with HG, and these levels were markedly reduced by pretreatment with DPx or metformin. DPx significantly reduced the levels of kidney injury molecule-1 (KIM-1), pyruvate kinase M2 (PKM2), selenium-binding protein 1 (SBP1), or neutrophil gelatinase-associated lipocalin (NGAL) in NRK-52E cells cultured under HG conditions. Furthermore, treatment with DPx significantly increased antioxidant enzyme activity. DPx protects against HG-induced renal tubular cell damage, which may be mediated by its ability to inhibit oxidative stress through the protein kinase B/mammalian target of the rapamycin (AKT/mTOR) signaling pathway. These findings suggest that DPx can be used as a new drug for the treatment of high glucose-induced diabetic nephropathy.
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Hiperglicemia , Metformina , Triterpenos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Linhagem Celular , Glucose/toxicidade , Estresse Oxidativo , Transdução de Sinais , Antioxidantes/farmacologia , Apoptose , Serina-Treonina Quinases TOR/metabolismo , Metformina/metabolismo , Metformina/farmacologia , Células Epiteliais/metabolismoRESUMO
P-glycoprotein (P-gp) overexpression is one of the major mechanisms of multidrug resistance (MDR). Previously, co-treatment with Janus kinase 2 (JAK2) inhibitors sensitized P-gp-overexpressing drug-resistant cancer cells. In this study, we assessed the cytotoxic effects of JAK2 inhibitor, fedratinib, on drug-resistant KBV20C cancer cells. We found that co-treatment with fedratinib at low doses induced cytotoxicity in KBV20C cells treated with vincristine (VIC). However, fedratinib-induced cytotoxicity was little effect on VIC-treated sensitive KB parent cells, suggesting that these effects are specific to resistant cancer cells. Fluorescence-activated cell sorting (FACS), Western blotting, and annexin V analyses were used to further investigate fedratinib's mechanism of action in VIC-treated KBV20C cells. We found that fedratinib reduced cell viability, increased G2 arrest, and upregulated apoptosis when used as a co-treatment with VIC. G2 phase arrest and apoptosis in VIC-fedratinib-co-treated cells resulted from the upregulation of p21 and the DNA damaging marker pH2AX. Compared with dimethyl sulfoxide (DMSO)-treated cells, fedratinib-treated KBV20C cells showed two-fold higher P-gp-inhibitory activity, indicating that VIC-fedratinib sensitization is dependent on the activity of fedratinib. Similar to VIC, fedratinib co-treatment with other antimitotic drugs (i.e., eribulin, vinorelbine, and vinblastine) showed increased cytotoxicity in KBV20C cells. Furthermore, VIC-fedratinib had similar cytotoxic effects to co-treatment with other JAK2 inhibitors (i.e., VIC-CEP-33779 or VIC-NVP-BSK805) at the same dose; similar cytotoxic mechanisms (i.e., early apoptosis) were observed between treatments, suggesting that co-treatment with JAK2 inhibitors is generally cytotoxic to P-gp-overexpressing resistant cancer cells. Given that fedratinib is FDA-approved, our findings support its application in the co-treatment of P-gp-overexpressing cancer patients showing MDR.
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Antimitóticos , Antineoplásicos , Inibidores de Janus Quinases , Neoplasias , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antimitóticos/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Humanos , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/metabolismo , Inibidores de Janus Quinases/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/genética , Pirrolidinas , Sulfonamidas , Vincristina/farmacologiaRESUMO
In the cochlea, non-sensory supporting cells are directly connected to adjacent supporting cells via gap junctions that allow the exchange of small molecules. We have previously shown that the pharmacological regulation of gap junctions alleviates cisplatin (CDDP)-induced ototoxicity in animal models. In this study, we aimed to identify specific small molecules that pass through gap junctions in the process of CDDP-induced auditory cell death and suggest new mechanisms to prevent hearing loss. We found that the cyclic adenosine monophosphate (cAMP) inducer forskolin (FSK) significantly attenuated CDDP-induced auditory cell death in vitro and ex vivo. The activation of cAMP/PKA/CREB signaling was observed in organ of Corti primary cells treated with FSK, especially in supporting cells. Co-treatment with gap junction enhancers such as all-trans retinoic acid (ATRA) and quinoline showed potentiating effects with FSK on cell survival via activation of cAMP/PKA/CREB. In vivo, the combination of FSK and ATRA was more effective for preventing ototoxicity compared to either single treatment. Our study provides the new insight that gap junction-mediated intercellular communication of cAMP may prevent CDDP-induced ototoxicity.
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Comunicação Celular , Cisplatino/efeitos adversos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Junções Comunicantes/metabolismo , Ototoxicidade/metabolismo , Transdução de Sinais , Células A549 , Animais , Comunicação Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Colforsina/farmacologia , Colforsina/uso terapêutico , Conexina 26/metabolismo , Junções Comunicantes/efeitos dos fármacos , Células Ciliadas Auditivas/metabolismo , Células HeLa , Perda Auditiva/induzido quimicamente , Perda Auditiva/tratamento farmacológico , Perda Auditiva/prevenção & controle , Humanos , Camundongos , Substâncias Protetoras/farmacologia , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/metabolismo , Gânglio Espiral da Cóclea/efeitos dos fármacos , Gânglio Espiral da Cóclea/patologia , Tretinoína/farmacologia , Tretinoína/uso terapêuticoRESUMO
Ocean acidification (OA) is caused by changes in ocean carbon chemistry due to increased atmospheric pCO2 and is predicted to have deleterious effects on marine ecosystems. While the potential impacts of OA on many marine species have been studied, the multigenerational effects on asexual organisms remain unknown. We found that low seawater pH induced oxidative stress and DNA damage, decreasing growth rates, fecundity, and lifespans in the parental generation, whereas deleterious effects on in vivo endpoints in F1 and F2 offspring were less evident. The findings suggest that multigenerational adaptive effects play a role in antioxidant abilities and other defense mechanisms. OA-induced DNA damage, including double-strand breaks (DSBs), was fully repaired in F1 offspring of parents exposed to OA for 7 days, indicating that an adaptation mechanism may be the major driving force behind multigenerational adaptive effects. Analysis of epigenetic modification in response to OA involved examination of histone modification of DNA repair genes and a chromatin immunoprecipitation assay, as Bombus koreanus has no methylation pattern for CpG in its genome. We conclude that DSBs, DNA repair, and histone modification play important roles in multigenerational plasticity in response to OA in an asexual monogonont rotifer.
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Antioxidantes , Água do Mar , Animais , Dióxido de Carbono , Dano ao DNA , Ecossistema , Epigênese Genética , Concentração de Íons de HidrogênioRESUMO
Glutathione S-transferases (GSTs) play an important role in phase II of detoxification to protect cells in response to oxidative stress generated by exogenous toxicants. Despite their important role in defense, studies on invertebrate GSTs have mainly focused on identification and characterization. Here, we isolated omega and sigma classes of GSTs from the freshwater rotifer Brachionus calyciflorus and the marine rotifer Brachionus koreanus and explored their antioxidant function in response to metal-induced oxidative stress. The recombinant Bc- and Bk-GSTs were successfully transformed and expressed in Escherichia coli. Their antioxidant potential was characterized by measuring kinetic properties and enzymatic activity in response to pH, temperature, and chemical inhibitor. In addition, a disk diffusion assay, reactive oxygen species assay, and morphological analysis revealed that GST transformed into E. coli significantly protected cells from oxidative stress induced by H2O2 and metals (Hg, Cd, Cu, and Zn). Stronger antioxidant activity was exhibited by GST-S compared to GST-O in both rotifers, suggesting that GST-S plays a prominent function as an antioxidant defense mechanism in Brachionus spp. Overall, our study clearly shows the antioxidant role of Bk- and Bc-GSTs in E. coli and provides a greater understanding of GST class-specific and interspecific detoxification in rotifer Brachionus spp.
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Escherichia coli , Metais Pesados , Animais , Água Doce , Glutationa Transferase , Peróxido de Hidrogênio , Isoformas de ProteínasRESUMO
Among the various materials found inside microplastic pollution, nanosized microplastics are of particular concern due to difficulties in quantification and detection; moreover, they are predicted to be abundant in aquatic environments with stronger toxicity than microsized microplastics. Here, we demonstrated a stronger accumulation of nanosized microbeads in the marine rotifer Brachionus koreanus compared to microsized ones, which was associated with oxidative stress-induced damages on lipid membranes. In addition, multixenobiotic resistance conferred by P-glycoproteins and multidrug resistance proteins, as a first line of membrane defense, was inhibited by nanoplastic pre-exposure, leading to enhanced toxicity of 2,2',4,4'-tetrabromodiphenyl ether and triclosan in B. koreanus. Our study provides a molecular mechanistic insight into the toxicity of nanosized microplastics toward aquatic invertebrates and further implies the significance of synergetic effects of microplastics with other environmental persistent organic pollutants.
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Poluentes Ambientais , Rotíferos , Triclosan , Poluentes Químicos da Água , Animais , Estresse Oxidativo , PlásticosRESUMO
INTRODUCTION: The purpose of this study was to assess the reproducibility of in-vivo and ex-vivo scans using an intraoral scanner. METHODS: Twenty adults with no missing teeth except for third molars were included in the study. Alginate impressions were taken, and plaster models were made from the impressions. Each subject underwent full-arch intraoral scanning twice with a TRIOS scanner (3Shape, Copenhagen, Denmark) at an interval of 2 weeks, and, the plaster models were scanned at the same interval with the same scanner. The first images of each scan were superimposed on the second scanned images using surface-based registration. In each case, the differences between the 2 scanned images were evaluated with color mapping. The reproducibility between the in-vivo and ex-vivo scans was compared using independent t tests and Bland-Altman analysis. RESULTS: The discrepancies between the first and second images were greater in the posterior than in the anterior regions for both the in-vivo and ex-vivo scans. Average surface differences between the first and second images were greater for the in-vivo scans (0.04 mm) than for the ex-vivo scans (0.02 mm). The Bland-Altman plots showed that the reproducibility of both scans was within the limits of agreement. CONCLUSIONS: The reproducibility of in-vivo scanning was comparable with ex-vivo scanning, although it showed a slight difference (0.02 mm) compared with ex-vivo scanning.
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Imageamento Tridimensional , Dente/diagnóstico por imagem , Adulto , Técnica de Moldagem Odontológica , Humanos , Reprodutibilidade dos TestesRESUMO
The minichromosome maintenance complex component 7 (MCM7) encodes a member of MCM complex, which plays a critical role in the initiation of gene replication. Due to the importance of MCM complex, MCM7 gene has been regarded as a candidate gene for cancer development. In the present study, seven MCM7 polymorphisms were genotyped in 344 subjects composed of 103 acute myeloid leukemia (AML) patients and 241 normal controls to examine the possible associations between MCM7 polymorphisms and the risk of AML. MCM7 polymorphisms were not associated with the risk of AML (P > 0.05). However, MCM7 polymorphisms were significantly related to the relapse of AML and overall survival. The rs2070215 (N144S) showed a protective effect to the risk of AML relapse (OR = 0.37; P corr = 0.02). In haplotype analyses, the ht1 and ht2 showed significant associations with the risk of AML relapse (P corr = 0.02-0.03). In addition, rs1534309 showed an association with the overall survival of AML patients. Patients with major homozygote genotype (CC) of rs1534309 showed a higher survival rate than the patients with other genotypes (CG and GG). The results of the present study indicate that MCM7 polymorphisms may be able to predict the prognosis of AML patients.
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Leucemia Mieloide Aguda/genética , Componente 7 do Complexo de Manutenção de Minicromossomo/genética , Recidiva Local de Neoplasia/genética , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Adulto , Idoso , Feminino , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/mortalidade , Taxa de Sobrevida/tendências , Adulto JovemRESUMO
Here, we infected mice with cytopathic bovine viral diarrhea virus 1 (cp BVDV1) by oral inoculation and investigated the effects of infection by histopathological, immunohistochemical (IHC), hematological methods. Twelve mice were infected, and samples were obtained at day 2, 5, and 9 postinfection (pi). Most of the infected mice exhibited clinical signs of illness such as reduced movement, crouching, loose feces, loss of appetite, and reduced water intake. Blood samples from six mice were positive for BVDV based on reverse transcription polymerase chain reaction (RT-PCR). Blood analysis also revealed thrombocytopenia and lymphopenia. Viral antigens were detected in the spleen (12/12), bone marrow (12/12), and/or mesenteric lymph nodes (4/12) of all infected mice by IHC analysis. The spleens showed significant histopathological changes including (i) substantially increased numbers of megakaryocytes, (ii) lymphocyte depletion, and (iii) hemorrhages. The bone marrow also had an increased number of megakaryocytes, although this increase was not as strong as it was in the spleen. Severe lymphoid depletion was observed in the mesenteric lymph nodes. Viral infections were present in the lymphocytes but not detected in megakaryocytes of the spleen, bone marrow, or mesenteric lymph nodes. These results suggest that the increased numbers of megakaryocytes may be a direct result of BVDV infection. BVDV infection in mice following oral inoculation of cp BVDV1 leads to megakaryopoiesis in the spleen and bone marrow to replenish the platelets.
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Medula Óssea/patologia , Doença das Mucosas por Vírus da Diarreia Viral Bovina/patologia , Vírus da Diarreia Viral Bovina/fisiologia , Baço/patologia , Trombopoese , Estruturas Animais/patologia , Estruturas Animais/virologia , Animais , Antígenos Virais/análise , Medula Óssea/virologia , Bovinos , Modelos Animais de Doenças , Histocitoquímica , Imuno-Histoquímica , Camundongos , Baço/virologiaRESUMO
Bovine viral diarrhea virus (BVDV) is an economically important pathogen that causes development of mild to severe clinical signs in wild and domesticated ruminants. We previously showed that mice could be infected by BVDV. In the present study, we infected mice intraperitoneally with non-cytopathic (ncp) BVDV1 or ncp BVDV2, harvested the blood and organs of the infected mice at days 4, 7, 10 and 14 postinfection (pi), and performed immunohistochemical analyses to confirm BVDV infection. Viral antigens were detected in the spleens of all infected mice from days 4 through 14 and were also found in the mesenteric lymph nodes, gut-associated lymphoid tissue (GALT), heart, kidney, intestine, and bronchus-associated lymphoid tissue (BALT) of some infected mice. In ncp BVDV2-infected mice, flow cytometric analysis revealed markedly fewer CD4(+) and CD8(+) T lymphocytes and lower expression of costimulatory molecules CD80 (B7-1) and CD86 (B7-2) and major histocompatibility complex (MHC) class II (I-A/I-E) than those in ncp BVDV1-infected mice. Production of the cytokines interleukin (IL)-6 and monocyte chemotactic protein (MCP)-1 was higher in the plasma of ncp BVDV2-infected mice than that in that of ncp BVDV1-infected mice. Our results demonstrate that ncp BVDV1 and ncp BVDV2 interact differently with the host innate immune response in vivo. These findings highlight an important distinction between ncp BVDV1 and ncp BVDV2 and suggest that ncp BVDV2 impairs the host's ability to control the infection and enhances virus dissemination.
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Vírus da Diarreia Viral Bovina Tipo 2/imunologia , Vírus da Diarreia Viral Bovina Tipo 2/patogenicidade , Infecções por Pestivirus/patologia , Infecções por Pestivirus/virologia , Estruturas Animais/virologia , Animais , Antígenos Virais/análise , Modelos Animais de Doenças , Citometria de Fluxo , Tolerância Imunológica , Imuno-Histoquímica , Injeções Intraperitoneais , Camundongos , Infecções por Pestivirus/imunologia , Subpopulações de Linfócitos T/imunologiaRESUMO
PURPOSE: Hirschsprung disease (HSCR) is a congenital and heterogeneous disorder, which is caused by no neuronal ganglion cells in part or all of distal gastrointestinal tract. Recently, our genome-wide association study has identified solute carrier family 6, proline IMINO transporter, member 20 (SLC6A20) as one of the potential risk factors for HSCR development. This study performed a replication study for the association of SLC6A20 polymorphisms with HSCR and an extended analysis to investigate further associations for subgroups and haplotypes. METHODS: For the replication study, a total of 40 single nucleotide polymorphisms (SNPs) of SLC6A20 were genotyped in 187 HSCR subjects composed of 121 short-segment HSCR, 45 long-segment HSCR (L-HSCR), 21 total colonic aganglionosis, and 283 unaffected controls. Imputation was performed using genotype data from our genome-wide association study and this replication study. RESULTS: Imputed meta-analysis revealed that 13 SLC6A20 SNPs (minimum P = 0.0002 at rs6770261) were significantly associated with HSCR even after correction for multiple comparisons using false discovery rate (FDR) (minimum PFDR =â .005). In further subgroup analysis, SLC6A20 polymorphisms appeared to have increased associations with L-HSCR. Moreover, haplotype analysis also showed significant associations between 2 haplotypes (BL3_ht2 and BL4_ht2) and HSCR susceptibility (PFDR <â .05). CONCLUSIONS: Although further replications and functional evaluations are required, our results suggest that SLC6A20 may have roles in HSCR development and in the extent of aganglionic segment during enteric nervous system development.
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Replicação do DNA , Doença de Hirschsprung/genética , Proteínas de Membrana Transportadoras/genética , Polimorfismo de Nucleotídeo Único , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Haplótipos , Humanos , MasculinoRESUMO
Triclosan (TCS) is an antibacterial agent commonly used in personal care products. Due to its widespread use and improper disposal, it is also a pervasive contaminant, particularly in aquatic environments. When released into water bodies, TCS can induce deleterious effects on developmental and physiological aspects of aquatic organisms and also interact with environmental stressors such as weather, metals, pharmaceuticals, and microplastics. Multiple studies have described the adverse effects of TCS on aquatic organisms, but few have reported on the interactions between TCS and other environmental conditions and pollutants. Because aquatic environments include a mix of contaminants and natural factors can correlate with contaminants, it is important to understand the toxicological outcomes of combinations of substances. Due to its lipophilic characteristics, TCS can interact with a wide range of substances and environmental stressors in aquatic environments. Here, we identify a need for caution when using TCS by describing not only the effects of exposure to TCS alone on aquatic organisms but also how toxicity changes when it acts in combination with multiple environmental stressors.
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Poluentes Ambientais , Triclosan , Poluentes Químicos da Água , Triclosan/análise , Organismos Aquáticos , Plásticos , Poluentes Químicos da Água/análiseRESUMO
The marine medaka Oryzias melastigma is a useful fish model for marine and estuarine ecotoxicology studies and can be applied to field-based population genomics because of its distribution in Asian estuaries and other coastal areas. We identified 769 full-length G protein-coupled receptor genes in the O. melastigma genome and classified them into five distinct classes. A phylogenetic comparison of GPCR genes in O. melastigma to humans and two other small fish species revealed a high-level orthological relationship. Purinergic and chemokine receptors were highly differentiated in humans whereas significant differentiation of chemosensory receptors was evident in fish species. Our results suggest that the GPCR gene families among the species used in this study exhibit evidence of sporadic evolutionary processes. These results may help improve our understanding of the advanced repertoires of GPCR and expand our knowledge of physiological mechanisms of fish in response to various environmental stimuli.
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Global warming and nanoplastics (NPs) are critical global issues. Among NPs, one of the most hazardous types of plastics, polystyrene (PS), poses ecotoxicological threats to several freshwater organisms. The degree of toxicity of PS-NPs is strongly influenced by various environmental factors. This study illustrates the combined effects of temperature and PS-NPs on the water flea Daphnia magna. The sensitivity of D. magna to PS-NPs was tested under control (23⯰C) and elevated temperatures (28⯰C). As a result, increased temperatures influenced the uptake and accumulation of PS-NPs. Co-exposure to both higher temperatures and PS-NPs resulted in a drastic decrease in reproductive performance. The level of oxidative stress was found to have increased in a temperature-dependent manner. Oxidative stress was stimulated by both stressors, leading to increased levels of reactive oxygen species and antioxidant enzyme activity supported by upregulation of antioxidant enzyme-related genes under combined PS-NPs exposure and elevated temperature. In the imbalanced status of intracellular redox, activation of the p38 mitogen-activated protein kinase signaling pathway was induced by exposure to PS-NPs at high temperatures, which supported the decline of the reproductive capacity of D. magna. Therefore, our results suggest that PS-NPs exposure along with an increase in temperature significantly affects physiological processes triggered by damage from oxidative stress, leading to severely inhibited reproduction of D. magna.
Assuntos
Cladocera , Poluentes Químicos da Água , Animais , Daphnia magna , Microplásticos/metabolismo , Temperatura , Antioxidantes/metabolismo , Daphnia , Plásticos/toxicidade , Poliestirenos/toxicidade , Água Doce , Poluentes Químicos da Água/análiseRESUMO
In this study, we investigated the combined effects of hypoxia and NPs on the water flea Daphnia magna, a keystone species in freshwater environments. To measure and understand the oxidative stress responses, we used acute toxicity tests, fluorescence microscopy, enzymatic assays, Western blot analyses, and Ingenuity Pathway Analysis. Our findings demonstrate that hypoxia and NPs exhibit a negative synergy that increases oxidative stress, as indicated by heightened levels of reactive oxygen species and antioxidant enzyme activity. These effects lead to more severe reproductive and growth impairments in D. magna compared to a single-stressor exposure. In this work, molecular investigations revealed complex pathway activations involving HIF-1α, NF-κB, and mitogen-activated protein kinase, illustrating the intricate molecular dynamics that can occur in combined stress conditions. The results underscore the amplified physiological impacts of combined environmental stressors and highlight the need for integrated strategies in the management of aquatic ecosystems.
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Daphnia magna , Estresse Oxidativo , Poluentes Químicos da Água , Animais , Daphnia magna/efeitos dos fármacos , Daphnia magna/fisiologia , Hipóxia , Espécies Reativas de Oxigênio/metabolismo , Poluentes Químicos da Água/toxicidadeRESUMO
Rapid, anthropogenic activity-induced global warming is a severe problem that not only raises water temperatures but also shifts aquatic environments by increasing the bioavailability of heavy metals (HMs), with potentially complicated effects on aquatic organisms, including small aquatic invertebrates. For this paper, we investigated the combined effects of temperature (23 and 28⯰C) and methylmercury (MeHg) by measuring physiological changes, bioaccumulation, oxidative stress, antioxidants, and the mitogen-activated protein kinase signaling pathway in the marine rotifer Brachionus plicatilis. High temperature and MeHg adversely affected the survival rate, lifespan, and population of rotifers, and bioaccumulation, oxidative stress, and biochemical reactions depended on the developmental stage, with neonates showing higher susceptibility than adults. These findings demonstrate that increased temperature enhances potentially toxic effects from MeHg, and susceptibility differs with the developmental stage. This study provides a comprehensive understanding of the combined effects of elevated temperature and MeHg on rotifers. ENVIRONMENTAL IMPLICATION: Methylmercury (MeHg) is a widespread and harmful heavy metal that can induce lethal effects on aquatic organisms in even trace amounts. The toxicity of metals can vary depending on various environmental conditions. In particular, rising temperatures are considered a major factor affecting bioavailability and toxicity by changing the sensitivity of organisms. However, there are few studies on the combinational effects of high temperatures and MeHg on aquatic animals, especially invertebrates. Our research would contribute to understanding the actual responses of aquatic organisms to complex aquatic environments.
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Metais Pesados , Compostos de Metilmercúrio , Rotíferos , Poluentes Químicos da Água , Animais , Compostos de Metilmercúrio/toxicidade , Compostos de Metilmercúrio/metabolismo , Temperatura , Organismos Aquáticos , Estresse Oxidativo , Metais Pesados/metabolismo , Poluentes Químicos da Água/metabolismoRESUMO
Here, we investigate the effects of acute and chronic exposure to arsenate (AsV) and arsenite (AsIII) in the marine medaka Oryzias melastigma. In vivo effects, biotransformation, and oxidative stress were studied in marine medaka exposed to the two inorganic arsenics for 4 or 28 days. An investigation of embryonic development revealed no effect on in vivo parameters, but the hatching rate increased in the group exposed to AsIII. Exposure to AsIII also caused the greatest accumulation of arsenic in medaka. For acute exposure, the ratio of AsV to AsIII was higher than that of chronic exposure, indicating that bioaccumulation of inorganic arsenic can induce oxidative stress. The largest increase in oxidative stress was observed following acute exposure to AsIII, but no significant degree of oxidative stress was induced by chronic exposure. During acute exposure to AsV, the increase in the enzymatic activity of glutathione-S-transferase (GST) was twice as high compared with exposure to AsIII, suggesting that GST plays an important role in the initial detoxification process. In addition, an RNA-seq-based ingenuity pathway analysis revealed that acute exposure to AsIII may be related to cell-cycle progression. A network analysis using differentially expressed genes also revealed a potential link between the generation of inflammatory cytokines and oxidative stress due to arsenic exposure.
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Arseniatos , Glutationa Transferase , Oryzias , Estresse Oxidativo , Poluentes Químicos da Água , Animais , Oryzias/metabolismo , Oryzias/genética , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Arseniatos/toxicidade , Glutationa Transferase/metabolismo , Glutationa Transferase/genética , Arsenitos/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismoRESUMO
In this study, we investigated the acute toxicity, in vivo effects, oxidative stress, and gene expression changes caused by hypoxia on the brackish water flea Diaphanosoma celebensis. The no-observed-effect concentration (NOEC) of 48 h of hypoxia exposure was found to be 2 mg/L O2. Chronic exposure to NOEC caused a significant decline in lifespan but had no effect on total fecundity. The induction of reactive oxygen species increased in a time-dependent manner over 48 h, whereas the content of antioxidant enzymes (superoxide dismutase and catalase) decreased. The transcription and translation levels were modulated by hypoxia exposure. In particular, a significant increase in hemoglobin level was followed by up-regulation of hypoxia-inducible factor 1α gene expression and activation of the mitogen-activated protein kinase pathway. In conclusion, our findings provide a better understanding of the molecular mechanism of the adverse effects of hypoxia in brackish water zooplankton.
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Estresse Oxidativo , Espécies Reativas de Oxigênio , Animais , Espécies Reativas de Oxigênio/metabolismo , Cladocera/efeitos dos fármacos , Cladocera/fisiologia , Hipóxia , Superóxido Dismutase/metabolismo , Catalase/metabolismo , Oxigênio/metabolismo , Águas SalinasRESUMO
Given the CYP3A4 and CYP3A5's impact on the efficacy of drugs, the genetic backgrounds of individuals and populations are regarded as an important factor to be considered in the prescription of personalized medicine. However, genetic studies with Korean population are relatively scarce compared to those with other populations. In this study, we aimed to identify CYP3A4/5 polymorphisms and compare the genotype distributions among five ethnicities. To identify CYP3A4/5 SNPs, we first performed direct sequencing with 288 DNA samples which consisted of 96 Koreans, 48 European-Americans, 48 African-Americans, 48 Han Chinese, and 48 Japanese. The direct sequencing identified 15 novel SNPs, as well as 42 known polymorphisms. We defined the genotype distributions, and compared the allele frequencies among five ethnicities. The results showed that minor allele frequencies of Korean population were similar with those of the Japanese and Han Chinese populations, whereas there were distinct differences from European-Americans or African-Americans. Among the pharmacogenetic markers, frequencies of CYP3A4*1B (rs2740574) and CYP3A5*3C (rs776742) in Asian groups were different from those in other populations. In addition, minor allele frequency of CYP3A4*18 (rs28371759) was the highest in Korean population. Additional in silico analysis predicted that two novel non-synonymous SNPs in CYP3A5 (+27256C>T, P389S and +31546T>G, I488S) could alter protein structure. The frequency distributions of the identified polymorphisms in the present study may contribute to the expansion of pharmacogenetic knowledge.
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Modern printed electronics applications require patterning of fine conductive lines of sufficient thickness. However, the two requirements for pattern width and thickness are a trade-off. To print fine pattern at a micrometer size, the nozzle diameter must be approximately the size of the pattern width, so only low-viscosity inks are used. As a result, the pattern is likely to be very thin and multiple overlapping printing is required for sufficient conductance. In order to use high viscosity ink for fine patterning, near field electrospinning (NFES) is attracting attention because it can print very thin and thick patterns using large nozzles (high-viscosity ink). Until now, silver paste ink has been used for microconductive patterning using electrospinning. However, Ag nanoparticle (NP) inks are expensive. In this study, we report the use of a relatively inexpensive CuO NP ink for electrospinning-based printing. For implementation, the material preparation, printing and post-processing process are discussed. For post-processing, a continuous wave (CW) green laser with a 532 nm wavelength was used to reduce the CuO to Cu and sinter the nanoparticles. After sintering, the 50 µm width and 1.48 µm thick Cu conductive line exhibited a resistivity of 5.46 µΩ·cm, which is 3.25 times of the bulk resistivity of Cu.