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1.
Toxicol Mech Methods ; 34(1): 32-45, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37664877

RESUMO

In the environment, or during mammalian metabolism, the diuron herbicide (3-(3,4-dichlorophenyl)-1,1-dimethylurea) is transformed mainly into 3-(3,4-dichlorophenyl)-1-methylurea (DCPMU) and 3,4-dichloroaniline (DCA). Previous research suggests that such substances are toxic to the urothelium of Wistar rats where, under specific exposure conditions, they may induce urothelial cell degeneration, necrosis, hyperplasia, and eventually tumors. However, the intimate mechanisms of action associated with such chemical toxicity are not fully understood. In this context, the purpose of the current in vitro study was to analyze the underlying mechanisms involved in the urothelial toxicity of those chemicals, addressing cell death and the possible role of mitochondrial dysfunction. Thus, human 1T1 urothelial cells were exposed to six different concentrations of diuron, DCA, and DCPMU, ranging from 0.5 to 500 µM. The results showed that tested chemicals induced oxidative stress and mitochondrial damage, cell cycle instability, and cell death, which were more expressive at the higher concentrations of the metabolites. These data corroborate previous studies from this laboratory and, collectively, suggest mitochondrial dysfunction as an initiating event triggering urothelial cell degeneration and death.


Assuntos
Herbicidas , Doenças Mitocondriais , Ratos , Animais , Humanos , Diurona/toxicidade , Diurona/metabolismo , Ratos Wistar , Herbicidas/toxicidade , Células Epiteliais/metabolismo , Mamíferos/metabolismo
2.
Front Genet ; 13: 886461, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35656327

RESUMO

Central areolar choroidal dystrophy (CACD) is a rare hereditary disease that mainly affects the macula, resulting in progressive and usually profound visual loss. Being part of congenital retinal dystrophies, it may have an autosomal dominant or recessive inheritance and, until now, has no effective treatment. Given the shortage of genotypic information about the disease, this work systematically reviews the literature for CACD-causing genes. Three independent researchers selected 33 articles after carefully searching and filtering the Scielo, Pubmed, Lilacs, Web of Science, Scopus, and Embase databases. Mutations of six genes (PRPH2, GUCA1A, GUCY2D, CDHR1, ABCA4, and TTLL5) are implicated in the monogenic dominant inheritance of CACD. They are functionally related to photoreceptors (either in the phototransduction process, as in the case of GUCY2D, or the recovery of retinal photodegradation in photoreceptors for GUCA1A, or the formation and maintenance of specific structures within photoreceptors for PRPH2). The identified genetic variants do not explain all observed clinical features, calling for further whole-genome and functional studies for this disease. A network analysis with the CACD-related genes identified in the systematic review resulted in the identification of another 20 genes that may influence CACD onset and symptoms. Furthermore, an enrichment analysis allowed the identification of 13 transcription factors and 4 long noncoding RNAs interacting with the products of the previously mentioned genes. If mutated or dysregulated, they may be directly involved in CACD development and related disorders. More than half of the genes identified by bioinformatic tools do not appear in commercial gene panels, calling for more studies about their role in the maintenance of the retina and phototransduction process, as well as for a timely update of these gene panels.

3.
J Toxicol Pathol ; 35(2): 159-170, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35516837

RESUMO

Exposure of Sprague-Dawley (SD) rats to acrylamide (AA) or di-butyl-phthalate (DBP) from the 12th gestational day to the 16th postnatal week (PNW) has been shown to reduce the effectiveness of orchiopexy in recovering the testicular alterations associated with experimental cryptorchidism established at weaning. Herein, we provide information about the long-term effects of AA or DBP on the testes of cryptorchid/orchiopexic rats. Male offspring exposed in utero to 10 mg/kg/day AA or 500 mg/kg/day DBP underwent bilateral surgical cryptorchidism at the 3rd PNW and orchiopexy at the 6th week, with continuous exposure to the chemicals through diet until the 58th week. Regardless of the test chemical, there were severe qualitative/quantitative alterations in the seminiferous tubules and increased numbers of Leydig cells. There was an increase and decrease in the number of tubules with c-Kit- and placental alkaline phosphatase-labeled germ cells, respectively, as compared to those in the control group, suggesting an imbalance between apoptosis and cell proliferation processes. The histological scores of the testicular lesions at the end of this one-year study were higher than those in the previous 16-week study, indicating that exposure of rats to the toxicants AA or DBP enhanced the testicular alterations induced by the chemicals beginning at the intra-uterine life, and impaired the effectiveness of orchiopexy in restoring the testes to normal morphology. Although the present experimental protocol does not completely replicate the natural human undescended testes, our findings may contribute to understanding the alterations occurring in cryptorchid/orchiopexic testes potentially exposed to exogenous chemicals for extended periods.

4.
Toxicol Mech Methods ; 32(8): 628-635, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35379061

RESUMO

Diuron, 3-(3,4-dichlorophenyl)-1,1-dimethylurea, is a worldwide used herbicide whose biotransformation gives rise to the metabolites, 3-(3,4-dichlorophenyl)-1-methylurea (DCPMU) and 3,4-dichloroaniline (DCA). Previous studies indicate that diuron and/or its metabolites are toxic to the bladder urothelium of the Wistar rats where, under certain conditions of exposure, they may induce successively urothelial cell degeneration, necrosis, hyperplasia and eventually tumors. The hypothesis was raised that the molecular initiating event (MIE) of this Adverse Outcome Pathway is the mitochondrial toxicity of those compounds. Therefore, this study aimed to investigate in vitro the metabolic alterations resulting from urothelial mitochondria isolated from male Wistar rats exposure to diuron, DCPMU and DCA at 10 and 100 µM. A non-targeted metabolomic analysis using mass spectrometry showed discriminative clustering among groups and alterations in the intensity abundance of membrane-associated molecules phosphatidylcholine, phosphatidylinositol and phosphatidylserine, in addition to methylhexanoyl-CoA and, particularly for diuron 100 µM, dehydro-L-gulonate, all of them involved in critical mitochondrial metabolism. Collectively, these data indicate the mitochondrial dysfunction as an MIE that triggers cellular damage and death observed in previous studies.


Assuntos
Diurona , Herbicidas , Animais , Diurona/metabolismo , Diurona/toxicidade , Herbicidas/toxicidade , Masculino , Mitocôndrias/metabolismo , Ratos , Ratos Wistar , Urotélio
5.
PLoS One ; 16(8): e0255726, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34383800

RESUMO

BACKGROUND: Parkinson's disease (PD) is a progressive multifactorial neurodegenerative condition. Epidemiological studies have shown that patients with type 2 diabetes mellitus (T2DM2) are at increased risk for developing PD, indicating a possible insulin-modulating role in this latter condition. We hypothesized that drugs similar to glucagon-like peptide-1 (GLP-1) and gastric inhibitory polypeptide (GIP), used in the treatment of T2DM2, may play a role in PD. OBJECTIVES: The purpose of this study is to systematically review and meta-analyze data of preclinical and clinical studies evaluating the efficacy and safety of GLP-1 and GIP drugs in the treatment of PD. METHODS: Two reviewers will independently evaluate the studies available in the Ovid Medline, Ovid Embase, Web of Science, Cochrane Central Register of Controlled Trials, Cinahl, and Lilacs databases. Preclinical rodent or non-human primate studies and randomized controlled human clinical trials will be included, without language or publication period restrictions. Outcomes of interest in preclinical studies will be primarily locomotor improvements and adverse effects in animal models of PD. For clinical trials, we will evaluate clinical improvements rated by the Movement Disorders Society Unified Parkinson's Disease Rating Scale-parts I, II, III, and IV, and adverse effects. The risk of bias of preclinical studies will be assessed by the SYRCLE tool and CAMARADES checklist and the clinical studies by the Cochrane tool; the certainty of the evidence will be rated by GRADE. DISCUSSION AND CONCLUSION: There is an urge for new PD treatments that may slow the progression of the disease rather than just restoring dopamine levels. This study will comprehensively review and update the state of the art of what is known about incretin hormones and PD and highlight the strengths and limitations of translating preclinical data to the clinic whenever possible. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration number CRD42020223435.


Assuntos
Diabetes Mellitus Tipo 2 , Peptídeo 1 Semelhante ao Glucagon , Receptor do Peptídeo Semelhante ao Glucagon 1 , Doença de Parkinson , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Progressão da Doença , Dopamina/metabolismo , Peptídeo 1 Semelhante ao Glucagon/agonistas , Peptídeo 1 Semelhante ao Glucagon/genética , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Receptor do Peptídeo Semelhante ao Glucagon 1/genética , Insulina/metabolismo , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/genética , Doença de Parkinson/patologia , Metanálise como Assunto , Revisões Sistemáticas como Assunto
6.
Int J Exp Pathol ; 102(1): 57-69, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33502821

RESUMO

Cryptorchidism is one of the main risk factors for infertility and testicular cancer. Orchiopexy surgery corrects cryptorchidism effects. Different models of cryptorchidism developed in the rat include surgery. We assessed testicular alterations in rats submitted to surgical cryptorchidism and examined their potential for reversibility at different time points in order to verify time dependency effect(s) on the recovery of the undescended testes. Cryptorchidism was induced in 3-week-old rats. Animals were euthanized 3, 6 or 11 weeks after surgery to evaluate the morphological progression of cryptorchidism-induced germinative epithelial alterations. Other groups underwent orchiopexy 3, 5 or 9 weeks after surgical cryptorchidism, before or after puberty. Animals were euthanized 3 or 8 weeks after orchiopexy. Controls underwent sham surgery at the same time points as the surgical groups. Cryptorchid testes showed decreased weight, germinative epithelial degeneration, apoptosis and vacuolation, corresponding to impairment of spermatogenesis and of Sertoli cells. Some tubules has a Sertoli cell-only pattern and atrophy. The intensity of damage was related to the duration of cryptorchidism. After orchiopexy, spermatogenesis completely recovered only when testicular relocation occurred before puberty and the interval for recovery was extended. These results indicate that age, sexual maturity and extension of germ cell damage were relevant for producing germ cell restoration and normal spermatogenesis. We provide original observations on the time dependency of testicular alterations induced by cryptorchidism and their restoration using morphologic, morphometric and immunohistochemical approaches. It may be useful to study germ cell impairment, progression and recovery in different experimental settings, including exposure to exogenous chemicals.


Assuntos
Criptorquidismo/patologia , Criptorquidismo/cirurgia , Orquidopexia/métodos , Testículo/patologia , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Espermatogênese/fisiologia , Fatores de Tempo
7.
Front Pediatr ; 9: 755144, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35402367

RESUMO

Neonatology has experienced a significant reduction in mortality rates of the preterm population and critically ill infants over the last few decades. Now, the emphasis is directed toward improving long-term neurodevelopmental outcomes and quality of life. Brain-focused care has emerged as a necessity. The creation of neonatal neurocritical care units, or Neuro-NICUs, provides strategies to reduce brain injury using standardized clinical protocols, methodologies, and provider education and training. Bedside neuromonitoring has dramatically improved our ability to provide assessment of newborns at high risk. Non-invasive tools, such as continuous electroencephalography (cEEG), amplitude-integrated electroencephalography (aEEG), and near-infrared spectroscopy (NIRS), allow screening for seizures and continuous evaluation of brain function and cerebral oxygenation at the bedside. Extended and combined uses of these techniques, also described as multimodal monitoring, may allow practitioners to better understand the physiology of critically ill neonates. Furthermore, the rapid growth of technology in the Neuro-NICU, along with the increasing use of telemedicine and artificial intelligence with improved data mining techniques and machine learning (ML), has the potential to vastly improve decision-making processes and positively impact outcomes. This article will cover the current applications of neuromonitoring in the Neuro-NICU, recent advances, potential pitfalls, and future perspectives in this field.

8.
J Toxicol Environ Health B Crit Rev ; 22(5-6): 172-202, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31476981

RESUMO

This investigation aimed to conduct a systematic review of the literature and meta-analysis to determine whether exposure to the herbicide paraquat was associated with the development of Parkinson's disease (PD). Observational studies that enrolled adults exposed to paraquat with PD as the outcome of interest were searched in the PubMed, Embase, LILACS, TOXNET, and Web of Science databases up to May 2019. Two authors independently selected relevant studies, extracted data, and assessed methodological quality. The evidence certainty was assessed by the GRADE approach, which served as basis for a tentative causality assessment, supplemented by the Bradford Hill criteria when necessary. Results from nine case-control studies indicated that PD occurrence was 25% higher in participants exposed to paraquat. The only cohort investigation included demonstrated a non-significant OR of 1.08. Results from subgroup analyses also indicated higher PD frequency in participants that were exposed to paraquat for longer periods or individuals co-exposed with paraquat and any other dithiocarbamate. Data indicate apositive association between exposure to paraquat and PD occurrence, but the weight-of-evidence does not enable one to assume an indisputable cause-effect relationship between these two conditions. Better designed studies are needed to increase confidence in results. Systematic Review Registration: PROSPERO CRD42017069994.


Assuntos
Herbicidas/toxicidade , Paraquat/toxicidade , Doença de Parkinson/etiologia , Adulto , Humanos , Doença de Parkinson/epidemiologia , Projetos de Pesquisa , Fatores de Tempo
9.
Toxicol Mech Methods ; 29(7): 488-498, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31050326

RESUMO

The increased incidence of testicular disorders in young men and the possible influence of environmental chemicals, such as dibutyl phthalate (DBP) and acrylamide (AA), requires experimental models for identifying modes of action. Most published reproductive toxicologic studies use RNA samples from the total testis to evaluate testicular gene expression; however, analyses of isolated cell types could provide a more specific tool. Among testicular germ cells, spermatogonia are critical since they represent the onset of spermatogenesis. This study aimed, (1) to establish a technique for spermatogonia isolation; (2) to apply this isolation technique to verify possible gene expression alterations (Pou5f1, Kitlg, Mki-67, Bak1 and Spry4) in prepubertal post-natal day, (PND24) and pubertal (PND45) testes after in utero and postnatal exposure to DBP or AA. The technique was efficient for isolation of a majority of spermatogonia. In utero DBP exposure led to reduced litter body weight at birth, reduced anogenital distance of male pups on PND4, and increased frequency of male nipple retention on PND14 compared to controls. DBP-exposed relative testes weights were reduced only at PND24 compared to control but they did not differ at PND45. DBP-exposed animals showed reduced expression levels of Pou5f1 and Mki67 on PND24, and reduced expression of Pou5f1 and Spry4 on PND45. AA exposure reduced expression of Pou5f1, Mki67, and Spry4 at PND45 although not significantly. Our results suggest that DBP acts by reducing cell proliferation and impairing differentiation in prepubertal and pubertal testes.


Assuntos
Acrilamida/toxicidade , Dibutilftalato/toxicidade , Poluentes Ambientais/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Espermatogônias/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Peso Corporal , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Feminino , Expressão Gênica/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Efeitos Tardios da Exposição Pré-Natal/patologia , Ratos Sprague-Dawley , Espermatogônias/patologia , Testículo/embriologia , Testículo/crescimento & desenvolvimento , Testículo/patologia
10.
Sensors (Basel) ; 18(2)2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-29364172

RESUMO

A wide range of multimedia services is expected to be offered for mobile users via various wireless access networks. Even the integration of Cloud Computing in such networks does not support an adequate Quality of Experience (QoE) in areas with high demands for multimedia contents. Fog computing has been conceptualized to facilitate the deployment of new services that cloud computing cannot provide, particularly those demanding QoE guarantees. These services are provided using fog nodes located at the network edge, which is capable of virtualizing their functions/applications. Service migration from the cloud to fog nodes can be actuated by request patterns and the timing issues. To the best of our knowledge, existing works on fog computing focus on architecture and fog node deployment issues. In this article, we describe the operational impacts and benefits associated with service migration from the cloud to multi-tier fog computing for video distribution with QoE support. Besides that, we perform the evaluation of such service migration of video services. Finally, we present potential research challenges and trends.

11.
Syst Rev ; 6(1): 98, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28506248

RESUMO

BACKGROUND: Parkinson's disease (PD) is a progressive neurodegenerative condition that has genetic susceptibility, aging, and exposure to certain chemicals as risk factors. In recent decades, epidemiological and experimental studies have investigated the role of pesticides in the development of PD, in particular that of the herbicide paraquat. Here, we, therefore, aim to systematically review the association between paraquat exposure and PD. METHODS: Observational studies (cohort, case-control, and cross-sectional) eligible for this systematic review will enroll any participant who was occupationally and/or environmentally exposed to paraquat. Experimental studies, including in vivo and in vitro assays designed to assess neurotoxicological endpoints or mechanisms of paraquat neurotoxicity, will also be eligible. Outcomes of interest include the following: PD diagnosis; neurobehavioral, biochemical, and/or morphological alterations; and cellular, biochemical, and/or molecular pathways to oxidative stress. Using terms to include all forms of paraquat combined with PD, the following electronic databases will be searched: PubMed, EMBASE, LILACS, Toxnet, and Web of Science, without restrictions as to language, year, or status of publication. A team of reviewers will independently select potential titles and abstracts, extract data, assess risk of bias, and determine the overall quality of evidence for each outcome using the Office of Health Assessment and Translation (OHAT) approach for systematic reviews and evidence integration. Dichotomous data will be summarized as odds ratios, and continuous data will be given as mean differences, both with their respective 95% confidence intervals. DISCUSSION: This is the first time that the OHAT systematic review protocol will be applied to investigate a possible causal association between exposure to paraquat and PD. Results from this study could serve as basis for regulatory agencies to define paraquat levels of concern, supporting its risk assessment process. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42016050861.


Assuntos
Exposição Ambiental/efeitos adversos , Paraquat/toxicidade , Doença de Parkinson Secundária/induzido quimicamente , Praguicidas/toxicidade , Projetos de Pesquisa , Literatura de Revisão como Assunto , Animais , Relação Dose-Resposta a Droga , Humanos , Vias Neurais/efeitos dos fármacos , Estudos Observacionais como Assunto , Paraquat/farmacocinética , Doença de Parkinson Secundária/fisiopatologia , Praguicidas/farmacocinética , Fatores de Risco , Revisões Sistemáticas como Assunto
12.
J Anal Toxicol ; 41(5): 399-406, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28334957

RESUMO

The concomitant exposure to low doses of various pesticides is one of the most relevant issues in human toxicology today. An experimental toxicology study was developed to evaluate the effects of this type of exposure on the reproductive capacity of females of three species of rats that were exposed to mixtures of dicofol, dieldrin, endosulfan and permethrin at low doses (LOAEL and NOAEL). In this context, we have developed a method for determining pesticides in adipose tissue (0.5 g, 49% lipid) associated with the ovaries, based on the QuEChERS (quick, easy, cheap, effective, rugged and safe) strategy. The method quantification limit (LOQ) was 0.5 mg/kg for dicofol and permethrin, 0.05 mg/kg for endosulfan and dieldrin and 0.2 mg/kg for diclorobenzophenone. Mean recoveries ranged from 75% to 93% with a relative standard deviation <13%. The unspecific selectivity (matrix effect) indicates the mandatory use of analytical curves constructed on the matrix extract. All the analyzed samples (53 adipose tissue associated to ovaries) showed residues of dichlorobenzophenone + dicofol, dieldrin and cis-permethrin while trans-permethrin were detected in 40% of the samples but were below the LOQ. The data indicated the bioaccumulation characteristics of these substances.


Assuntos
Tecido Adiposo/metabolismo , Ovário/metabolismo , Resíduos de Praguicidas/análise , Praguicidas/metabolismo , Tecido Adiposo/química , Animais , Monitoramento Ambiental , Feminino , Praguicidas/análise , Ratos
13.
Toxicol Pathol ; 44(8): 1146-1159, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-28245158

RESUMO

The medium-term multiorgan initiation-promotion chemical bioassay (diethylnitrosamine, methyl-nitrosourea, butyl-hydroxybutylnitrosamine, dihydroxypropylnitrosamine, dimethylhydrazine [DMBDD]) with the Fischer 344 rat was proposed as an alternative to the conventional 2-year carcinogenesis bioassay for regulatory purposes. The acronym DMBDD stands for the names of five genotoxic agents used for initiation of multiorgan carcinogenesis. The Brazilian Agency for the Environment officially recognized a variation of this assay (DMBDDb) as a valid method to assess the carcinogenic potential of agrochemicals. Different from the original protocol, this DMBDDb is 30-week long, uses Wistar rats and two positive control groups exposed to carcinogenesis promoters sodium phenobarbital (PB) or 2-acetylaminofluorene (2-AAF). This report presents the experience of an academic laboratory with the DMBDDb assay and contributes to the establishment of this alternative DMBDD bioassay in a different rat strain. Frequent lesions observed in positive groups to evaluate the promoting potential of pesticides and the immunohistochemical expressions of liver cytochrome P450 (CYP) 2B1/2B2 and CYP1A2 enzymes were assessed. Commonly affected organs were liver, kidney, intestines, urinary bladder, and thyroid. PB promoting activity was less evident than that of 2-AAF, especially in males. This study provides a repository of characteristic lesions occurring in positive control animals submitted to a modified alternative 2-stage multiorgan protocol for carcinogenesis in Wistar rat.


Assuntos
2-Acetilaminofluoreno/toxicidade , Testes de Carcinogenicidade/métodos , Carcinógenos/toxicidade , Neoplasias Experimentais/induzido quimicamente , Fenobarbital/toxicidade , Lesões Pré-Cancerosas/induzido quimicamente , Animais , Hidrocarboneto de Aril Hidroxilases/biossíntese , Bioensaio , Citocromo P-450 CYP1A2/biossíntese , Citocromo P-450 CYP2B1/biossíntese , Feminino , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/patologia , Masculino , Neoplasias Experimentais/enzimologia , Tamanho do Órgão/efeitos dos fármacos , Especificidade de Órgãos , Lesões Pré-Cancerosas/enzimologia , Ratos Wistar , Esteroide Hidroxilases/biossíntese
14.
J Toxicol Environ Health A ; 78(9): 602-16, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25965195

RESUMO

The Brazilian federal government Agency for Health Surveillance detected pesticide residues in fresh food available for consumers all over the country. The current study investigated the effects of a mixture of some of those pesticides (dichlorvos, dicofol, dieldrin, endosulfan, and permethrin) on the reproductive system of Sprague-Dawley (SD), Wistar (WT), and Lewis (LEW) rats. Female rats from each strain were randomized into three experimental groups and were fed a control diet or diets added with pesticides mixture at their respective no-observed-effect level (NOEL)/no-observed-adverse-effect level (NOAEL) (low dose) (mg/kg/d): dichlorvos (0.23), dicofol (0.5), dieldrin (0.025), endosulfan (0.7), permethrin (5), or lowest-observed-effect level (LOEL)/lowest-effect level (LEL)/ lowest-observed-adverse-effect level (LOAEL) (toxically effective dose) (mg/kg/d): dichlorvos (2.3), dicofol (2.1), dieldrin (0.05), endosulfan (3.8), and permethrin (25) as reported in the literature. Euthanasia was performed between wk 10 and 12, during the estrous stage. Decreased body weights gain (SD and WT) and increased liver weights (SD, WT, and LEW) were observed in each strain fed the pesticides mixture at the higher levels. At that dose level, rat strains also varied in their responses regarding the estrous cycle, hormonal levels, and number of developing ovarian follicles. The studied mixture of pesticides was found to interfere with the female reproductive system when individual pesticides were mixed above a certain level, indicating a threshold exists for each of the strains studied.


Assuntos
Genitália Feminina/efeitos dos fármacos , Inseticidas/toxicidade , Ratos/metabolismo , Animais , Relação Dose-Resposta a Droga , Feminino , Nível de Efeito Adverso não Observado , Distribuição Aleatória , Ratos Endogâmicos Lew , Ratos Sprague-Dawley , Ratos Wistar
15.
PLoS One ; 9(1): e86162, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24465937

RESUMO

Bladder cancer is one of the most common genitourinary neoplasms in industrialized countries. Multifocality and high recurrence rates are prominent clinical features of this disease and contribute to its high morbidity. Therefore, more sensitive and less invasive techniques could help identify individuals with asymptomatic disease. In this context, we used the micronucleus assay to evaluate whether cytogenetic alterations could be used as biomarkers for monitoring patients with a history of urothelial cell carcinoma (UCC). We determined the frequency of micronucleated urothelial cells (MNC) in exfoliated bladder cells from 105 patients with (n = 52) or without (n = 53) a history of UCC, all of whom tested negative for neoplasia by cytopathological and histopathological analyses. MNC frequencies were increased in patients with a history of UCC (non-smoker and smoker/ex-smoker patients vs non-smoker and smoker/ex-smoker controls; p<0.001), in non-smoker UCC patients (vs non-smoker controls; p<0.01), and in smoker/ex-smoker controls (vs non-smoker controls; p<0.001). Patients with a history of recurrent disease also demonstrated a higher MNC frequency compared to patients with non-recurrent neoplasia. However, logistic regression using smoking habits, age and gender as confounding factors did not confirm MNC frequency as a marker for UCC recurrence. Fluorescent in situ hybridization analysis (using a pan-centromeric probe) showed that micronuclei (MN) arose mainly from clastogenic events regardless of UCC and/or smoking histories. In conclusion, our results confirm previous indications that subjects with a history of UCC harbor genetically unstable cells in the bladder urothelium. Furthermore, these results support using the micronucleus assay as an important tool for monitoring patients with a history of UCC and tumor recurrence.


Assuntos
Carcinoma/genética , Células Epiteliais/metabolismo , Instabilidade Genômica , Neoplasias Urológicas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/patologia , Estudos de Casos e Controles , Células Epiteliais/patologia , Feminino , Humanos , Masculino , Micronúcleos com Defeito Cromossômico , Testes para Micronúcleos , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Fatores de Risco , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Neoplasias Urológicas/patologia
16.
Histopathology ; 63(5): 678-85, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24025158

RESUMO

AIMS: To investigate the prognostic value of expression levels of the genes STEAP1 and STEAP2, and of STEAP1 protein, in prostate carcinomas (PCa). METHODS AND RESULTS: STEAP1 and STEAP2 transcript levels were evaluated by RT-qPCR in samples from 35 PCa, 24 adjacent non-neoplastic prostate (AdjP) tissues, five cases of benign prostatic hyperplasia (BPH), and two histologically normal prostates (N). STEAP1 expression was assessed by immunohistochemistry in samples from 198 PCa, 76 AdjP, 22 BPH, and two N. The findings were compared with clinical and pathological parameters and patient outcome. STEAP1 and STEAP2 transcript analysis showed no differences between the groups tested. Although not significant, higher STEAP1 mRNA levels were detected in tumours with high Gleason scores and in patients who presented with biochemical recurrence (BCR). STEAP1 overexpression was detected in PCa, and was significantly associated with high-grade Gleason scores, seminal vesicle invasion, BCR, and worse outcome (metastasis or PCa-specific death). STEAP1 overexpression was significantly associated with shorter BCR-free survival. Multivariate analysis revealed that STEAP1 is an independent marker for BCR. CONCLUSIONS: These findings provide evidence that STEAP1 is a biomarker of worse prognosis in PCa patients.


Assuntos
Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma/diagnóstico , Recidiva Local de Neoplasia/diagnóstico , Oxirredutases/metabolismo , Neoplasias da Próstata/diagnóstico , Idoso , Antígenos de Neoplasias/genética , Carcinoma/metabolismo , Carcinoma/patologia , Humanos , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Oxirredutases/genética , Prognóstico , Estudos Prospectivos , Próstata/metabolismo , Próstata/patologia , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia
17.
J Environ Sci Health B ; 48(7): 607-13, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23581695

RESUMO

The noxious effects of low or effective dose exposure to single or mixed pesticides on macrophage activity and the lymphohematopoietic organs were investigated. Male Wistar rats were orally exposed to dichlorvos, dicofol, endosulfan, dieldrin and permethrin, either as single or combined mixtures during a 28-day study containing eight groups: one group received a semipurified diet (non-treated); two groups received a semipurified diet containing low dose mixture (dieldrin 0.025 mg/kg, endosulfan, 0.6 mg/kg, dicofol 0.22 mg/kg, dichlorvos 0.23 mg/kg, permethrin 5 mg/kg) or an effective dose mixture (dichlorvos 2.3 mg/kg, dicofol 2.5 mg/kg, endosulfan 2.9 mg/kg, dieldrin 0.05 mg/kg and permethrin 25.0 mg/kg), respectively; the other five groups received a semipurified diet containing each single pesticide in effective doses. At sacrifice, the thymus, spleen, mesenteric lymph nodes, Payer's patches and bone marrow were removed for histological analysis. Peritoneal macrophages were obtained to determine the phagocytosis and spreading indexes and tumoral necrosis factor alpha (TNF-α), nitric oxide (NO) and H2O2 production. Exposure to pesticide mixtures did not alter the percentage of macrophage phagocytosis and spreading, TNF-α production or the NO and H2O2 release when compared to the non-treated group. Neither was there any apparent evidence that a pesticide mixture at low or effective doses altered the histological structure of the lymphohematopoietic organs. The findings indicate that short-term treatment with pesticide mixtures did not induce an apparent immunotoxic effect in male Wistar rats.


Assuntos
Medula Óssea/efeitos dos fármacos , Tecido Linfoide/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Praguicidas/toxicidade , Animais , Medula Óssea/imunologia , Células Cultivadas , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Tecido Linfoide/imunologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Ratos , Ratos Wistar , Baço/efeitos dos fármacos , Baço/imunologia , Timo/efeitos dos fármacos , Timo/imunologia , Fator de Necrose Tumoral alfa/imunologia
18.
Urol Oncol ; 31(6): 827-35, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21763161

RESUMO

OBJECTIVE: To understand developmental characteristics of urinary bladder carcinomas (UBC) by evaluating genomic alterations and p53 protein expression in primary tumors, their recurrences, and in the morphologically normal urothelium of UBC patients. METHODS: Tumors and their respective recurrences, six low-grade and five high-grade cases, provided 19 samples that were submitted to laser microdissection capture followed by high resolution comparative genomic hybridization (HR-CGH). HR-CGH profiles went through two different analyses--all tumors combined or classified according to their respective histologic grades. In a supplementary analysis, 124 primary urothelial tumors, their recurrences, and normal urothelium biopsied during the period between tumor surgical resection and recurrence, were submitted to immunohistochemical analyses of the p53 protein. During the follow-up of at least 21 patients, urinary bladder washes citologically negative for neoplastic cells were submitted to fluorescence in situ hybridization (FISH) to detect copy number alterations in centromeres 7, 17, and 9p21 region. RESULTS AND CONCLUSIONS: HR-CGH indicated high frequencies (80%) of gains in 11p12 and losses in 16p12, in line with suggestions that these chromosome regions contain genes critical for urinary bladder carcinogenesis. Within a same patient, tumors and their respective recurrences showed common genomic losses and gains, which implies that the genomic profile acquired by primary tumors was relatively stable. There were exclusive genomic alterations in low and in high grade tumors. Genes mapped in these regions should be investigated on their involvement in the urinary bladder carcinogenesis. Successive tumors from same patient did not present similar levels of protein p53 expression; however, when cases were grouped according to tumor histologic grades, p53 expression was directly proportional to tumor grades. Biopsies taken during the follow-up of patients with history of previously resected UBC revealed that 5/15 patients with no histologic alterations had more than 25% of urothelial cells expressing the p53 protein, suggesting that the apparently normal urothelium was genomically unstable. No numerical alterations of the chromosomes 7, 17, and 9p21 region were found by FISH during the periods "free-of-neoplasia." Our data are informative for further studies to better understand urinary bladder urothelial carcinogenesis.


Assuntos
Carcinoma de Células de Transição/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias da Bexiga Urinária/genética , Urotélio/patologia , Idoso , Idoso de 80 Anos ou mais , Desequilíbrio Alélico , Biópsia , Centrômero/ultraestrutura , Mapeamento Cromossômico , Hibridização Genômica Comparativa , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Recidiva , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
19.
20.
Talanta ; 101: 322-9, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23158329

RESUMO

This report describes the development and validation of a simple, rapid, and efficient method in which solid-phase extraction followed by analysis in a gas chromatograph equipped with an electron capture detector (SPE-GC-ECD) is used for the simultaneous determination of dicofol, dieldrin, endosulfan, and permethrin in rat adipose tissue. This study targeted pesticides for which controversies exist regarding the harm that they may cause to humans, such as endocrine disruption or cancer, and that have also been found in recent years in vegetables consumed by the Brazilian population. The analytical procedure was optimised for SPE extraction and for GC-ECD conditions. The optimised method includes the extraction of the samples with n-hexane followed by an SPE procedure in which deactivated neutral alumina cartridges are used as the sorbent and a mixture of n-hexane:dichloromethane is used for elution. Recovery studies with spiked samples were used to evaluate the method's efficiency. Mean recoveries ranged from 75% to 119% with relative standard deviations (RSD)<19%. Quantification limits (LOQs) were 0.05 mg kg(-1) for dieldrin and endosulfan and 0.5 mg kg(-1) for dicofol and permethrin. The matrix effect was pronounced for all of the pesticides studied and ranged from 26% to 49%. In comparison to other related methods, this method requires less time and solvent and allows for rapid isolation of the target analytes with high selectivity. This method therefore allows for the screening of numerous samples and can also be used for routine analyses.


Assuntos
Tecido Adiposo/química , Praguicidas/análise , Animais , Cromatografia Gasosa , Limite de Detecção , Ratos , Reprodutibilidade dos Testes
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