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1.
Bull Environ Contam Toxicol ; 112(5): 66, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38643435

RESUMO

In this study, the toxicogenomic effects of five cytostatics (tamoxifen, methotrexate, capecitabine, cyclophosphamide, and ifosfamide) on fathead minnow (Pimephales promelas) larvae were evaluated. Post-fertilization eggs were exposed to increasing concentrations of the drugs for six days. The expression levels of two genetic biomarkers for toxicity and four thyroid hormone-related gene pathways were measured. Interestingly, the results showed that all concentrations of the five cytostatics affect the transcription levels of both toxicity biomarker genes. Additionally, the thyroid hormone-related genes had different expression levels than the control, with the most significant changes observed in those larvae exposed to cyclophosphamide and ifosfamide. While a previous study found no effects on fish morphology, this study suggests that the five cytostatics modify subtle molecular responses of P. promelas, highlighting the importance of assessing multibiological level endpoints throughout the lifecycle of animals to understand the full portrait of potential effects of cytostatics and other contaminants.


Assuntos
Cyprinidae , Citostáticos , Animais , Larva , Ifosfamida , Toxicogenética , Cyprinidae/genética , Ciclofosfamida , Hormônios Tireóideos
3.
Appl Opt ; 62(14): 3637-3642, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37706980

RESUMO

An optical fiber pH sensor based on a multimode interference structure is presented. The sensitive element is a piece of no-core fiber (NCF) coated with a mixture of polyallylamine hydrochloride and polyacrylic acid by a modified layer-by-layer (LbL) self-assembly method. It is experimentally shown that by reducing the diameter of the NCF by chemical etching, the sensitivity is increased from -0.31n m/p H to -2n m/p H. The sensor exhibits a high linear response of 0.997 over a pH range from 5 to 11.3 with a rapid response time lower than 1 s.

4.
Acta Paediatr ; 112(7): 1574-1585, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37129464

RESUMO

AIM: Children often fall sick, which causes concern among parents. Online health information can be confusing and difficult to understand. We aimed to produce simple, informative video tutorials on the symptoms ill children present. METHODS: We used a modified Delphi method to produce video tutorials on the symptoms of fever, vomiting and diarrhoea, abdominal pain, breathing difficulties, sore throat, red eyes, earache and rash. We identified the most common symptoms in acutely ill children. During the first consensus round, experts rated statements on out-of-hospital management from existing health information. Video tutorials were produced from statements rated to be included. The second consensus round involved video showings and editing. Two videos were evaluated in focus groups by parents. RESULTS: During the first round, experts rated a median of 79 (40-154) statements for each symptom. Panels consisted of a median of seven (6-11) experts, primarily. Panels reached a consensus on inclusion, neutrality or exclusion in 83% of statements. The second round led to adjustments to the videos and final approval by experts. Most parents evaluated the videos as 'informative, easy to understand and calming'. CONCLUSION: We produced video tutorials on the common symptoms ill children present using a modified Delphi method. Feedback from parents in focus groups was positive.


Assuntos
Pais , Humanos , Criança , Técnica Delphi , Doença Aguda , Consenso , Grupos Focais
5.
JDS Commun ; 4(2): 116-120, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36974221

RESUMO

The objective of this randomized clinical study was to evaluate the effects of periparturient administration of pegbovigrastim (recombinant bovine granulocyte colony stimulating factor; PEG) on postpartum health and reproductive outcomes in dairy cows carrying transferred embryos. A total of 60 multiparous Jersey cows (second parity n = 21, >second parity n = 39) that were in vitro-fertilized embryo recipients were enrolled. Animals were selected from a commercial herd and assigned to 1 of 2 treatments: (1) PEG (n = 31), which received a subcutaneous injection of 15 mg of PEG 7 d before expected calving and a second dose within 1 h of parturition; or (2) CON, untreated control (n = 29). Parturition was induced pharmacologically in all cows at 280 d of pregnancy with 500 µg of cloprostenol and 25 mg of dexamethasone intramuscularly. Cow health was monitored daily during the periparturient period and included assessment for retained fetal membranes within 24 h after calving and metritis until 20 d in milk. Descriptive statistics were calculated, to determine the incidence of postpartum diseases, causes of culling, and early-lactation reproductive outcomes, including number of inseminations, days to first heat, days to first service, and interval from calving to conception. The Wilcoxon rank sum test was used to assess treatment effects on early-lactation reproductive performance outcomes. The overall incidence of metritis in this cohort of cows was 17.14%. Animals treated with PEG tended to have more cases of metritis (25%) compared with CON (8.8%). Mastitis incidence in PEG was 19.35% compared with CON at 27.59%. These data suggest that in this dairy, with embryo-recipient cows induced to calve at 280 d of pregnancy, the administration of 2 doses of PEG tended to increase postpartum metritis but had no effect on mastitis incidence, culling rate, or early-lactation reproductive outcomes.

6.
Sci Rep ; 12(1): 16944, 2022 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-36210380

RESUMO

The combination of molecular tools, standard surveying techniques, and long-term monitoring programs are relevant to understanding environmental and ecological changes in coral reef communities. Here we studied temporal variability in cryptobenthic coral reef communities across the continental shelf in the central Red Sea spanning 6 years (three sampling periods: 2013-2019) and including the 2015 mass bleaching event. We used a combination of molecular tools (barcoding and metabarcoding) to assess communities on Autonomous Reef Monitoring Structures (ARMS) as a standardized sampling approach. Community composition associated with ARMS for both methodologies (barcoding and metabarcoding) was statistically different across reefs (shelf position) and time periods. The partition of beta diversity showed a higher turnover and lower nestedness between pre-bleaching and post-bleaching samples than between the two post-bleaching periods, revealing a community shift from the bleaching event. However, a slight return to the pre-bleaching community composition was observed in 2019 suggesting a recovery trajectory. Given the predictions of decreasing time between bleaching events, it is concerning that cryptobenthic communities may not fully recover and communities with new characteristics will emerge. We observed a high turnover among reefs for all time periods, implying a homogenization of the cryptobiome did not occur across the cross shelf following the 2015 bleaching event. It is possible that dispersal limitations and the distinct environmental and benthic structures present across the shelf maintained the heterogeneity in communities among reefs. This study has to the best of our knowledge presented for the first time a temporal aspect into the analysis of ARMS cryptobenthic coral reef communities and encompasses a bleaching event. We show that these structures can detect cryptic changes associated with reef degradation and provides support for these being used as long-term monitoring tools.


Assuntos
Antozoários , Animais , Recifes de Corais , Oceano Índico
7.
Sci Adv ; 8(37): eabn1731, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36112676

RESUMO

Voltage-gated K+ (Kv) channels mediate the flow of K+ across the cell membrane by regulating the conductive state of their activation gate (AG). Several Kv channels display slow C-type inactivation, a process whereby their selectivity filter (SF) becomes less or nonconductive. It has been proposed that, in the fast inactivation-removed Shaker-IR channel, the W434F mutation epitomizes the C-type inactivated state because it functionally accelerates this process. By introducing another pore mutation that prevents AG closure, P475D, we found a way to record ionic currents of the Shaker-IR-W434F-P475D mutant at hyperpolarized membrane potentials as the W434F-mutant SF recovers from its inactivated state. This W434F conductive state lost its high K+ over Na+ selectivity, and even NMDG+ can permeate, features not observed in a wild-type SF. This indicates that, at least during recovery from inactivation, the W434F-mutant SF transitions to a widened and noncationic specific conformation.

8.
Neurologia (Engl Ed) ; 37(6): 428-433, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35779866

RESUMO

INTRODUCTION: Percutaneous endoscopic gastrostomy (PEG) is a useful intervention for patients with impaired swallowing and a functional gastrointestinal system. Neurological diseases that cause neuromotor dysphagia, brain tumors, and cerebrovascular disease are the most frequent indications; complications are rare, and morbidity and mortality rates are low. OBJECTIVE: To describe the usefulness of PEG in patients with neurological diseases, and its impact on care, survival, and costs and benefits. MATERIAL AND METHODS: We performed a retrospective observational study, reviewing clinical files of patients hospitalised at the National Institute of Neurology and Neurosurgery (years 2015-2017) who underwent PEG placement. RESULTS: The sample included 51 patients: 62.7% were women and the mean (SD) age was 54.4 (18.6) years (range, 18-86). Diagnosis was tumor in 37.3% of cases and cerebrovascular disease in 33.3%. Sixteen patients (33.3%) died and 11 presented minor complications. The PEG tube remained in place for a mean of 9.14 months; in 52.9% of patients it was removed due to lack of improvement and/or tolerated oral intake, with removal occurring after a mean of 5.1 (4.4) months. Among patients' family members, 78.4% reported a great benefit, 43.1% reported difficulty caring for the PEG, and 45.1% reported complicated care in general. The monthly cost of maintaining the PEG was €175.78 on average (range, 38.38-293.45). DISCUSSION AND CONCLUSIONS: This preliminary study reveals that PEG was well indicated in patients with neurological diseases, with survival rates similar to those reported in other studies with long follow-up periods. In patients with cerebrovascular disease, the PEG tube remained in place a mean of 9.14 months, during recovery of swallowing function; however, the cost is high for our population.


Assuntos
Neoplasias Encefálicas , Transtornos Cerebrovasculares , Transtornos de Deglutição , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtornos de Deglutição/etiologia , Nutrição Enteral/efeitos adversos , Feminino , Gastrostomia/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Environ Res ; 208: 112584, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-34951986

RESUMO

Endocrine disrupting chemicals (EDCs) are ubiquitous in aquatic and terrestrial environments. The main objective of this review was to summarize the current knowledge of the impacts of EDCs on reproductive success in wildlife and humans. The examples selected often include a retrospective assessment of the knowledge of reproductive impacts over time to discern how the effects of EDCs have changed over the last several decades. Collectively, the evidence summarized here within reinforce the concept that reproduction in wildlife and humans is negatively impacted by anthropogenic chemicals, with several altering endocrine system function. These observations of chemicals interfering with different aspects of the reproductive endocrine axis are particularly pronounced for aquatic species and are often corroborated by laboratory-based experiments (i.e. fish, amphibians, birds). Noteworthy, many of these same indicators are also observed in epidemiological studies in mammalian wildlife and humans. Given the vast array of reproductive strategies used by animals, it is perhaps not surprising that no single disrupted target is predictive of reproductive effects. Nevertheless, there are some general features of the endocrine control of reproduction, and in particular, the critical role that steroid hormones play in these processes that confer a high degree of susceptibility to environmental chemicals. New research is needed on the implications of chemical exposures during development and the potential for long-term reproductive effects. Future emphasis on field-based observations that can form the basis of more deliberate, extensive, and long-term population level studies to monitor contaminant effects, including adverse effects on the endocrine system, are key to addressing these knowledge gaps.


Assuntos
Disruptores Endócrinos , Animais , Animais Selvagens , Disruptores Endócrinos/toxicidade , Sistema Endócrino , Humanos , Mamíferos , Reprodução , Estudos Retrospectivos
11.
Cell Mol Life Sci ; 77(21): 4223-4236, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32367192

RESUMO

The determination of sex is an important hallmark in the life cycle of organisms, in which the fate of gonads and then the individual sex are defined. In gonochoristic teleost fish, this process is characterized by a high plasticity, considering that in spite of genotypic sex many environmental factors can cause shifts from one to another molecular pathway, resulting in organisms with mismatching genotypic and phenotypic sexes. Interestingly, in most instances, both female-to-male or male-to-female sex-reversed individuals develop functional gonads with normal gametogenesis and respective progenies with full viability. The study of these mechanisms is being spread to other non-model species or to those inhabiting more extreme environmental conditions. Although water temperature is an important mechanism involved in sex determination, there are other environmental stressors affected by the climate change which are also implicated in stress response-induced masculinization in fish. In this regard, the brain has emerged as the transducer of the environment input that can influence the gonadal fate. Furthermore, the evaluation of other environmental stressors or their synergic effect on sex determination at conditions that simulate the natural environments is growing gradually. Within such scope, the concerns related to climate change impacts rely on the fact that many of biotic and abiotic parameters reported to affect sex ratios are expected to increase concomitantly as a result of increased greenhouse gas emissions and, particularly worrying, many of them are related to male bias in the populations, such as high temperature, hypoxia, and acidity. These environmental changes can also generate epigenetic changes in sex-related genes affecting their expression, with implications on sex differentiation not only of exposed individuals but also in following generations. The co-analysis of multi-stressors with potential inter- and transgenerational effects is essential to allow researchers to perform long-term predictions on climate change impacts in wild populations and for establishing highly accurate monitoring tools and suitable mitigation strategies.


Assuntos
Peixes/fisiologia , Processos de Determinação Sexual , Animais , Mudança Climática , Meio Ambiente , Epigênese Genética , Feminino , Peixes/genética , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Diferenciação Sexual , Estresse Fisiológico
12.
J Hum Nutr Diet ; 33(6): 862-868, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32378264

RESUMO

BACKGROUND: Different nutritional screening instruments can be used to identify the risk of malnutrition in advanced chronic liver disease patients. The present study aimed to evaluate and compare two nutrition screening tools with the Global Leadership Initiative on Malnutrition (GLIM) diagnostic criteria for malnutrition in patients with advanced chronic liver disease. METHODS: Two nutritional screening tools, Nutritional Risk Screening 2002 (NRS-2002) and Royal Free Hospital Nutritional Prioritizing Tool (RFH-NPT), were assessed for 166 patients with liver cirrhosis. We compared medium/high nutritional risk screening with the diagnosis of malnutrition, using the GLIM criteria as the reference standard. RESULTS: According to the GLIM criteria, 57.3% of the patients were malnourished. NRS and RFH-NPT identified, respectively, 36.1% and 52.4% of patients with nutritional risk. RFH-NPT presented better agreement with the diagnosis according to GLIM criteria (k = 0.64; 95% confidence interval = 0.52-0.75), higher sensitivity (80%), higher negative predictive value (79%) and larger area under the curve (82.3%) compared to the NRS. CONCLUSIONS: RFH-NPT, when compared with the GLIM method, has substantial agreement in identifying nutritional risk, good sensitivity and good value for diagnosing malnutrition in patients with advanced chronic liver disease.


Assuntos
Doença Hepática Terminal/classificação , Desnutrição/diagnóstico , Programas de Rastreamento/métodos , Avaliação Nutricional , Medição de Risco/métodos , Idoso , Estudos Transversais , Doença Hepática Terminal/complicações , Doença Hepática Terminal/fisiopatologia , Feminino , Humanos , Masculino , Desnutrição/etiologia , Pessoa de Meia-Idade , Estado Nutricional , Índice de Gravidade de Doença
13.
RSC Adv ; 10(10): 5712-5721, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35497434

RESUMO

A planar solid-state photocapacitor with two electrodes has been prepared for the first time using a passivated film of ZnS with Ag2S quantum dots deposited on ZnO nanorods, which were electrochemically grown on ZnO seed layers, as the photoanode. The supercapacitor part is composed of a electrodeposited poly(3,4-ethylene-dioxythiophene) PEDOT film as the counter-electrode and an ionic liquid-based electrolyte between them deposited by the dip coating method. The different nanostructures and electrodes were morphologically and structurally characterized, and the device was electrochemically characterized and could reach a potential of 0.33 V during photocharge and a storage efficiency of 6.83%.

14.
Proc Natl Acad Sci U S A ; 116(34): 16829-16834, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31387976

RESUMO

Here, we present the atomic resolution crystallographic structure, the function, and the ion-binding properties of the KcsA mutants, G77A and G77C, that stabilize the 2,4-ion-bound configuration (i.e., water, K+, water, K+-ion-bound configuration) of the K+ channel's selectivity filter. A full functional and thermodynamic characterization of the G77A mutant revealed wild-type-like ion selectivity and apparent K+-binding affinity, in addition to showing a lack of C-type inactivation gating and a marked reduction in its single-channel conductance. These structures validate, from a structural point of view, the notion that 2 isoenergetic ion-bound configurations coexist within a K+ channel's selectivity filter, which fully agrees with the water-K+-ion-coupled transport detected by streaming potential measurements.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Canais de Potássio/química , Canais de Potássio/metabolismo , Permeabilidade da Membrana Celular , Cristalografia por Raios X , Ativação do Canal Iônico , Íons , Modelos Moleculares , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Conformação Proteica , Estabilidade Proteica
15.
Neurologia (Engl Ed) ; 2019 Jul 20.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31337557

RESUMO

INTRODUCTION: Percutaneous endoscopic gastrostomy (PEG) is a useful intervention for patients with impaired swallowing and a functional gastrointestinal system. Neurological diseases that cause neuromotor dysphagia, brain tumors, and cerebrovascular disease are the most frequent indications; complications are rare, and morbidity and mortality rates are low. OBJECTIVE: To describe the usefulness of PEG in patients with neurological diseases, and its impact on care, survival, and costs and benefits. MATERIAL AND METHODS: We performed a retrospective observational study, reviewing clinical files of patients hospitalised at the National Institute of Neurology and Neurosurgery (years 2015-2017) who underwent PEG placement. RESULTS: The sample included 51 patients: 62.7% were women and the mean (SD) age was 54.4 (18.6) years (range, 18-86). Diagnosis was tumor in 37.3% of cases and cerebrovascular disease in 33.3%. Sixteen patients (33.3%) died and 11 presented minor complications. The PEG tube remained in place for a mean of 9.14 months; in 52.9% of patients it was removed due to lack of improvement and/or tolerated oral intake, with removal occurring after a mean of 5.1 (4.4) months. Among patients' family members, 78.4% reported a great benefit, 43.1% reported difficulty caring for the PEG, and 45.1% reported complicated care in general. The monthly cost of maintaining the PEG was €175.78 on average (range, 38.38-293.45). DISCUSSION AND CONCLUSIONS: This preliminary study reveals that PEG was well indicated in patients with neurological diseases, with survival rates similar to those reported in other studies with long follow-up periods. In patients with cerebrovascular disease, the PEG tube remained in place a mean of 9.14 months, during recovery of swallowing function; however, the cost is high for our population.

16.
Appl Opt ; 58(14): 3856-3861, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31158200

RESUMO

A temperature sensor based on a multimode interference thermometer is designed and fabricated. The operation mechanism is based on the thermal expansion of a specific volume of ethylene glycol contained in a glass bulb that is connected to a capillary of the same material, with a no-core fiber (NCF) inserted and centered into the capillary tube. As the temperature is increased, the liquid is expanded, and the NCF is gradually covered by the liquid, resulting in a peak wavelength shift that is correlated to the temperature variations. A sensitivity of 0.4447 nm/°C and highly linear response with an R2 of 0.99962 are obtained. The advantage of this configuration is that the sensing temperature range can be adjusted by changing either the inner diameter of the capillary tube or the bulb volume. We can also measure negative temperatures by simply modifying the freezing point of the liquid, which demonstrates the viability of the sensor for many applications.

17.
Lupus ; 28(2): 217-222, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30661452

RESUMO

OBJECTIVE: To analyze the utility of neutrophil-to-lymphocyte ratio (NLR) plus C-reactive protein (CRP) to differentiate between infection and active disease in patients with SLE. METHODS: A cross-sectional study of a cohort of patients with SLE was carried out. Blood samples from four groups (patients without infection or active disease, patients with infection, patients with active disease, and patients with both infection and active disease) before therapeutic interventions were analyzed. We excluded patients with current malignancy, pregnancy, ischemic heart disease or use of antimicrobials during previous 7 days. Hematological cell count, CRP and cultures were obtained. We constructed receiver operating characteristic curves; sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated. RESULTS: Forty patients were included. NLR cut-off ≥6.3 had sensitivity 70%, specificity 85%, PPV 83% and NPV 74% to detect patients with non-viral infections. A CRP cut-off ≥7.5 mg/L had sensitivity 90%, specificity 75%, PPV 78% and NPV 88% to detect infections regardless of SLE activity. Combination of CRP plus NLR improves the specificity to 90% and PPV to 88%. Excluding the group with both infection and active disease, CRP plus NLR expands specificity to 95% and NPV to 90%. CONCLUSION: In our experience, levels of CRP, particularly CRP plus NLR, were useful in differentiating patients with SLE from those with suspected non-viral infection regardless of the activity of the disease.


Assuntos
Proteína C-Reativa/análise , Infecções/diagnóstico , Lúpus Eritematoso Sistêmico/sangue , Linfócitos , Neutrófilos , Adolescente , Adulto , Idoso , Biomarcadores , Estudos Transversais , Feminino , Humanos , Infecções/sangue , Infecções/complicações , Contagem de Leucócitos , Lúpus Eritematoso Sistêmico/complicações , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Adulto Jovem
18.
Chem Commun (Camb) ; 54(76): 10762-10765, 2018 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-30198534

RESUMO

A solid-state transparent photocapacitor has been prepared for the first time by the use of two transparent electrodes (TiO2 and LiFeO2) and also a transparent ion gel-based electrolyte between them, reaching a transmittance of 57% at λ = 555 nm, a specific capacitance of 2.98 µF cm-2 and a specific energy of 0.54 µJ cm-2.

19.
Proc Natl Acad Sci U S A ; 115(21): 5426-5431, 2018 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-29735651

RESUMO

The selectivity filter and the activation gate in potassium channels are functionally and structurally coupled. An allosteric coupling underlies C-type inactivation coupled to activation gating in this ion-channel family (i.e., opening of the activation gate triggers the collapse of the channel's selectivity filter). We have identified the second Threonine residue within the TTVGYGD signature sequence of K+ channels as a crucial residue for this allosteric communication. A Threonine to Alanine substitution at this position was studied in three representative members of the K+-channel family. Interestingly, all of the mutant channels exhibited lack of C-type inactivation gating and an inversion of their allosteric coupling (i.e., closing of the activation gate collapses the channel's selectivity filter). A state-dependent crystallographic study of KcsA-T75A proves that, on activation, the selectivity filter transitions from a nonconductive and deep C-type inactivated conformation to a conductive one. Finally, we provide a crystallographic demonstration that closed-state inactivation can be achieved by the structural collapse of the channel's selectivity filter.


Assuntos
Ativação do Canal Iônico/fisiologia , Canais de Potássio/química , Canais de Potássio/metabolismo , Potássio/metabolismo , Alanina/química , Alanina/genética , Alanina/metabolismo , Regulação Alostérica , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cristalografia por Raios X , Células HEK293 , Humanos , Modelos Moleculares , Mutação , Canais de Potássio/genética , Conformação Proteica , Treonina/química , Treonina/genética , Treonina/metabolismo
20.
Toxicol Appl Pharmacol ; 346: 19-27, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29540303

RESUMO

Methyl parathion (Me-Pa) is an oxidizing organophosphate (OP) pesticide that generates reactive oxygen species (ROS) through its biotransformation. Some studies have also suggested that OP pesticides have the capacity to alkylate biomolecules, including DNA. In general, DNA methylation in gene promoters represses transcription. NRF2 is a key transcription factor that regulates the expression of antioxidant, metabolic and detoxifying genes through the antioxidant response element (ARE) situated in promoters of regulated genes. Furthermore, DNA repair genes, including 8-oxoguanine DNA glycosidase (OGG1), have been proposed as NRF2 target genes. Me-Pa exposure produces poor semen quality, genetic and oxidative damage in sperm cells, and reduced fertility. However, the Me-Pa effects on the methylation status and the expression of antioxidant (Nrf2) or DNA repair (Ogg1) genes in male germ cells have not been investigated. Therefore, mice were exposed to Me-Pa to evaluate the global (%5-mC) and specific methylation of Nrf2 and Ogg1 genes using pyrosequencing, gene expression, and total protein carbonylation in male germ cells. The results showed that Me-Pa significantly decreased the global DNA methylation pattern and significantly increased the methylation of two CpG sites within Ogg1 promoter and one CpG site within Nrf2 promoter. In addition, Ogg1 or Nrf2 expression did not change after Me-Pa exposure despite the oxidative damage produced. Altogether, our data suggest that Me-Pa toxicity alters Ogg1 and Nrf2 promoter methylation in male germ cells that may be modulating their gene expression.


Assuntos
DNA Glicosilases/genética , Epigênese Genética/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Células Germinativas/efeitos dos fármacos , Metil Paration/efeitos adversos , Fator 2 Relacionado a NF-E2/genética , Testículo/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/genética , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/genética , Epigênese Genética/genética , Regulação da Expressão Gênica/genética , Células Germinativas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Testículo/metabolismo
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