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1.
BJOG ; 131(5): 589-597, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38239019

RESUMO

OBJECTIVE: To study the association between maternal exposure to arsenic, cadmium, lead, manganese and mercury, time-to-pregnancy (TTP) and infertility. DESIGN: Pregnancy-based retrospective TTP cohort study. SETTING: Hospitals and clinics from ten cities across Canada. POPULATION: A total of 1784 pregnant women. METHODS: Concentrations of arsenic, cadmium, lead, manganese and mercury were measured in maternal whole blood during the first trimester of pregnancy as a proxy of preconception exposure. Discrete-time Cox proportional hazards models generated fecundability odds ratios (FOR) for the association between metals and TTP. Logistic regression generated odds ratios (OR) for the association between metals and infertility. Models were adjusted for maternal age, pre-pregnancy body mass index, education, income, recruitment site and plasma lipids. MAIN OUTCOME MEASURES: TTP was self-reported as the number of months of unprotected intercourse to become pregnant. Infertility was defined as TTP longer than 12 months. RESULTS: A total of 1784 women were eligible for the analysis. Mean ± SD maternal age and gestational age at interview were 32.2 ± 5.0 years, and 11.6 ± 1.6 weeks, respectively. Exposure to arsenic, cadmium, manganese or mercury was not associated with TTP or infertility. Increments of one standard deviation of lead concentrations resulted in a shorter TTP (adjusted FOR 1.09, 95% CI 1.02-1.16); however, the association was not linear when exposure was modelled in tertiles. CONCLUSION: Blood concentrations of metals at typical levels of exposure among Canadian pregnant women were not associated with TTP or infertility. Further studies are needed to assess the role of lead, if any, on TTP.


Assuntos
Arsênio , Infertilidade , Mercúrio , Feminino , Gravidez , Humanos , Exposição Materna , Estudos de Coortes , Manganês , Chumbo , Tempo para Engravidar , Cádmio/efeitos adversos , Estudos Retrospectivos , Canadá
2.
Environ Res ; 217: 114842, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36410462

RESUMO

BACKGROUND: Glyphosate is the most widely applied herbicide in agriculture. Glufosinate is a broad spectrum herbicide used to manage glyphosate-resistant weeds. Despite the widespread use of these herbicides, biomonitoring data - which inform risk assessment and management - are sparse. OBJECTIVES: To identify determinants of urinary concentrations of these herbicides and their metabolites in pregnancy. METHODS: We measured urinary concentrations of glyphosate, glufosinate, and their primary metabolites aminomethylphosphonic acid (AMPA) and 3-methylphosphinicopropionic acid (3-MPPA) in a single spot urine specimen collected during the first trimester of pregnancy from the Maternal-Infant Research on Environmental Chemicals (MIREC) study. MIREC recruited about 2000 pregnant women from 10 Canadian cities between 2008 and 2011. We used UItra-Performance Liquid Chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) with sensitive limits of detection to quantify analyte concentrations. We examined urinary concentrations according to maternal sociodemographics, sample collection characteristics, reported pesticide use, and consumption of fruits, vegetables, legumes, and grain products. We used ANOVA models with specific gravity-standardized chemical concentrations as the dependent variable to determine associations with maternal and sample determinants. RESULTS: Among women with biobanked urine samples (n = 1829-1854), 74% and 72% had detectable concentrations of glyphosate and AMPA, respectively. In contrast, one and six percent of women had detectable concentrations of glufosinate and 3-MPPA, respectively. The specific gravity-standardized geometric mean (95% CI) concentrations of glyphosate and AMPA were 0.112 (0.099-0.127) µg/L and 0.159 (0.147-0.172) µg/L, respectively. We observed a dose-response relationship between consumption of whole grain bread and higher urinary glyphosate concentrations. Season of urine collection and self-reported pesticide use were not associated with increased concentrations of any analyte. CONCLUSIONS: We detected glyphosate and AMPA in the majority of pregnant women from this predominantly urban Canadian cohort. Diet was a probable route of exposure.


Assuntos
Herbicidas , Espectrometria de Massas em Tandem , Humanos , Feminino , Gravidez , Cromatografia Líquida , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico , Canadá , Verduras , Herbicidas/análise , Glifosato
3.
J Obstet Gynaecol Can ; 45(1): 11-20, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36455861

RESUMO

OBJECTIVES: To describe the use and perceived effectiveness of medical, surgical, and alternative therapies (e.g., diet, exercise, heat, cannabis, etc.) in managing endometriosis-associated pain in Canadians. METHODS: A cross-sectional online survey was distributed via The Endometriosis Network Canada (TENC) from February to March 2021. Canadians aged 18-50 years with diagnosed or suspected endometriosis were eligible to participate. RESULTS: A total of 434 survey responses were included, and 93.8% of respondents reported that they used at least 1 alternative therapy in the past 6 months for endometriosis-associated pain. Respondents used an array of medical (2.3/6 months), surgical (1.7/lifetime), and alternative therapies (6.9/6 months) to manage their pain, yet 61.9% of respondents did not feel it was adequately managed. The most common alternative therapies were heat, meditation/mindfulness/rest, and diet. CONCLUSION: Alternative therapies were commonly used by Canadians living with endometriosis to manage pain. Cannabis and heat were perceived as the most effective alternative therapies. Here, we gain a better understanding of alternative therapies that can provide an additional therapeutic avenue that clinicians and people living with endometriosis may wish to discuss and explore.


Assuntos
Cannabis , Terapias Complementares , Endometriose , Feminino , Humanos , Endometriose/complicações , Endometriose/terapia , Endometriose/epidemiologia , Canadá/epidemiologia , Prevalência , Estudos Transversais , Dor Pélvica/diagnóstico
4.
Biol Reprod ; 105(5): 1075-1085, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34244742

RESUMO

Endometriosis is a common gynecological condition characterized by estrogen dependence, chronic pelvic pain, infertility, and diagnostic delay of between 5.4 and 12 years. Despite extensive study, no biomarker, either alone or in combination with other markers, has proven superior to laparoscopy for the diagnosis of endometriosis. Recent studies report that circulating levels of differentially expressed microRNA (miRNA) in women with endometriosis compared with controls are potential diagnostic tools. However, the lack of replication and absence of validated differential expression in novel study populations have led some to question the diagnostic value of miRNA. To elucidate potential reasons for the lack of replication of study results and explore future directions to enhance replicability of circulating miRNA results, we carried out an electronic search of the miRNA literature published between 2000 and 2020. Eighteen studies were identified in which 63 different miRNAs were differentially expressed in the circulation of women with endometriosis compared with controls. However, the differential expressions of only 14 miRNAs were duplicated in one or more studies. While individual miRNAs lacked diagnostic value, miRNA panels yielded sensitivity and specificity equal to or better than laparoscopy in five studies. Important differences in study design, sample processing, and analytical methods were identified rendering direct comparisons across studies problematic and could account for the lack of reproducibility of study results. We conclude that while the results of miRNA studies to date are encouraging, refinements to study design and analytical methods should enhance the reliability of circulating miRNA for the diagnosis of endometriosis.


Assuntos
Endometriose/metabolismo , MicroRNAs/sangue , Biomarcadores/sangue , Endometriose/sangue , Feminino , Humanos
5.
Reprod Biomed Online ; 43(3): 370-378, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34272164

RESUMO

Endometriosis is a chronic oestrogen-dependent gynaecological disorder characterized by non-menstrual pelvic pain, infertility and the extrauterine growth of endometrial-like glands and stroma. It has been noted that the eutopic endometrium of women with endometriosis is functionally distinct from that of women without endometriosis. Moreover, ectopic endometrial implants are functionally different from the eutopic endometrium of women with endometriosis. However, the mechanisms directing these differences are ill-defined. It is proposed here that small membrane-bound extracellular vesicles called exosomes are important vehicles in the protection and transport of signalling molecules central to the dysregulation of endometrial function in women with endometriosis. Therefore, a critical review of the literature linking exosomes and their cargo to the pathobiology of endometriosis was conducted. Circulating peritoneal fluid and endometrial cell exosomes contained long non-coding RNA, miRNA and proteins involved in histone modification, angiogenesis and immune modulation that differed significantly in women with endometriosis compared with controls. Moreover, experimental evidence supports a role for exosomes and their cargo in angiogenesis, neurogenesis, immune modulation and endometrial stromal cell invasion. It is therefore suggested that exosomes play an important role in the pathophysiology of endometriosis.


Assuntos
Endometriose/fisiopatologia , Endométrio/fisiologia , Exossomos/fisiologia , Doenças Peritoneais/fisiopatologia , Endometriose/genética , Endometriose/metabolismo , Endometriose/patologia , Endométrio/citologia , Células Epiteliais/fisiologia , Exossomos/metabolismo , Feminino , Humanos , Sistema Imunitário/fisiopatologia , MicroRNAs/metabolismo , MicroRNAs/fisiologia , Neovascularização Patológica/fisiopatologia , Doenças Peritoneais/genética , Doenças Peritoneais/metabolismo , Doenças Peritoneais/patologia , Proteínas/metabolismo , Proteínas/fisiologia , RNA não Traduzido/metabolismo , RNA não Traduzido/fisiologia , Células Estromais/fisiologia
6.
BMC Pregnancy Childbirth ; 21(1): 18, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407226

RESUMO

BACKGROUND: Postpartum depression (PPD) is a highly prevalent mental health problem that affects parental health with implications for child health in infancy, childhood, adolescence and beyond. The primary aim of this study was to critically appraise available systematic reviews describing interventions for PPD. The secondary aim was to evaluate the methodological quality of the included systematic reviews and their conclusions. METHODS: An electronic database search of MEDLINE, Embase, and the Cochrane Library from 2000 to 2020 was conducted to identify systematic reviews that examined an intervention for PPD. A Measurement Tool to Assess Systematic Reviews was utilized to independently score each included systematic review which was then critically appraised to better define the most effective therapeutic options for PPD. RESULTS: Of the 842 studies identified, 83 met the a priori criteria for inclusion. Based on the systematic reviews with the highest methodological quality, we found that use of antidepressants and telemedicine were the most effective treatments for PPD. Symptoms of PPD were also improved by traditional herbal medicine and aromatherapy. Current evidence for physical exercise and cognitive behavioural therapy in treating PPD remains equivocal. A significant, but weak relationship between AMSTAR score and journal impact factor was observed (p = 0.03, r = 0.24; 95% CI, 0.02 to 0.43) whilst no relationship was found between the number of total citations (p = 0.27, r = 0.12; 95% CI, - 0.09 to 0.34), or source of funding (p = 0.19). CONCLUSION: Overall the systematic reviews on interventions for PPD are of low-moderate quality and are not improving over time. Antidepressants and telemedicine were the most effective therapeutic interventions for PPD treatment.


Assuntos
Depressão Pós-Parto/terapia , Antidepressivos/uso terapêutico , Aromaterapia , Terapia Cognitivo-Comportamental , Exercício Físico , Feminino , Humanos , Medicina Tradicional Chinesa , Fitoterapia , Telemedicina , Resultado do Tratamento
7.
BMC Womens Health ; 21(1): 19, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413295

RESUMO

BACKGROUND: Women with endometriosis are commonly treated by their sole provider. In this single-provider model of care, women frequently report long diagnostic delays, unresolved pelvic pain, multiple laparoscopic surgeries, sequential consultations with numerous providers, and an overall dissatisfaction with care. The emergence of multidisciplinary endometriosis centers aims to reduce diagnostic delays, improve pain management, and promote patient satisfaction; however, baseline data at the time of presentation to a multidisciplinary center are lacking. METHODS: A real-world, retrospective, single-site, cross-sectional study of women with surgically confirmed and/or clinically diagnosed endometriosis generated baseline data for a planned longitudinal assessment of multidisciplinary care of endometriosis. The primary objective was to determine the proportion of patients experiencing mild, moderate, or severe pain for dysmenorrhea, non-menstrual pelvic pain (NMPP), and dyspareunia at entry into a multidisciplinary endometriosis clinic. Also explored were relationships between pain scores and clinical endpoints obtained from electronic medical records. RESULTS: More than half (59%) of the study participants (n = 638) reported experiencing pelvic pain for ≥ 5 years. Pain intensity was highest for patients reporting dysmenorrhea, followed by NMPP, and dyspareunia. Significant correlations were observed between total pelvic pain and patient age (r = -0.22, p < 0.001, n = 506) and number of previous healthcare providers (r = 0.16, p = 0.006, n = 292); number of previous providers and duration of pain (r = 0.21, p = < 0.0001, n = 279); and duration of pain and years since diagnosis (r = 0.60, p < 0.001, n = 302). Mean pain scores differed significantly by age group for dysmenorrhea (p < 0.001), NMPP (p = 0.005), and total pelvic pain (p < 0.001), but not for dyspareunia (p = 0.06), with the highest mean pain scores reported among those < 30 years of age. CONCLUSION: These real-world data indicate that in the single-provider model of care, unresolved pelvic pain is common among women with endometriosis. Alternative care models, including a multidisciplinary approach, need to be evaluated for improvements in clinical outcomes. These data also highlight the importance of addressing NMPP, which may be particularly troublesome for patients.


Assuntos
Dispareunia , Endometriose , Adulto , Estudos Transversais , Dismenorreia/epidemiologia , Dismenorreia/etiologia , Dispareunia/epidemiologia , Dispareunia/etiologia , Endometriose/complicações , Feminino , Humanos , Dor Pélvica/etiologia , Estudos Retrospectivos
8.
Arch Gynecol Obstet ; 304(6): 1417-1426, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34495378

RESUMO

PURPOSE: Induction of labour has become more common over the last decade, together with an increase in the number of systematic reviews of the subject. However, with multiple systematic reviews it is necessary to evaluate the methodological rigor to ensure the reliability of conclusions and recommendations for clinical practice. Therefore, the aim of this study was to appraise the quality of systematic reviews that examined the efficacy and/or safety of labour induction methods. METHODS: An electronic search of MEDLINE, Embase, and the Cochrane Library from 2000 to 2020 was conducted. Study selection, data extraction and quality assessment were conducted using A Measurement Tool to Assess Systematic Reviews (AMSTAR) by two independent reviewers, in duplicate. RESULTS: The search identified 387 publications, of which 48 studies (13%) met the a priori inclusion criteria. No significant relationships were found between study quality and number of citations, journal impact factor, or publication year. CONCLUSION: Methodological quality for systematic reviews on the induction of labour were ranked as moderate with no significant changes in quality over the past 2 decades. Publication characteristics are not significantly associated with methodological quality, indicating that healthcare professionals should critically appraise studies before applying them to practice.


Assuntos
Trabalho de Parto Induzido , Revisões Sistemáticas como Assunto , Feminino , Humanos , Gravidez
9.
Environ Res ; 179(Pt A): 108736, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31541908

RESUMO

Fetal exposure to some toxic metals has been associated with reduced fetal growth, but the impact of contemporary, low-level metals on anthropometric measures in childhood is not well understood. Our primary objective was to quantify associations between childhood levels of toxic metals and concurrently measured body mass index (BMI) in a population of Canadian preschool-aged children. We collected biomonitoring data and anthropometric measures on 480 children between the ages of two and five years in the Maternal-Infant Research on Environmental Chemicals (MIREC) Child Development Plus study. Concentrations of four toxic metals (lead, arsenic, cadmium, and mercury) were measured in whole blood collected from pregnant women and their children. Blood levels of key essential elements were also measured in children. Children's weight, height, and BMI z-scores were calculated using the World Health Organization growth standards. We used a series of linear regression models, adjusted for potential parental confounders, concurrently measured metals and elements, and prenatal blood metal levels, to evaluate associations between tertiles of each toxic metal and anthropometric measures. We tested for effect modification by sex. Of the 480 children, 449 (94%) were singleton births and had complete biomonitoring and anthropometric data. The majority of children had detectable concentrations of metals. In the adjusted models, girls with blood lead concentrations in the highest tertile (>0.82 µg/dL) had, on average, 0.26 (95% Cl: -0.55, 0.03) lower BMI z-scores than those in the referent category. In contrast, boys with lead levels in the highest tertile had, on average, 0.14 higher BMI z-scores (95% Cl: -0.14, 0.41) (p-value heterogeneity = 0.04). In this population of Canadian preschool-aged children with low-level blood lead concentrations, we observed effect modification by sex in the association between Pb and BMI but no statistically significant associations in the sex-specific strata. Child blood levels of As, Cd, and Hg were not associated with childhood BMI, weight, or height in boys or girls.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/sangue , Metais/sangue , Arsênio , Peso Corporal , Canadá , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Chumbo , Masculino , Gravidez
10.
Environ Res ; 177: 108593, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31357157

RESUMO

Anogenital distance (AGD) has been used as a marker of fetal androgen action to identify endocrine disrupting chemicals. A US study (TIDES) has reported that the association between some phthalates and reduced AGD in males was only apparent in sons of mothers reporting no stressful life events (SLEs) during pregnancy. The objective of the current study was to examine the potential modifying effect of SLEs and their subjective impact on associations between prenatal phthalates and AGD. First trimester urines from the MIREC Study were analysed for phthalate metabolites and AGD was measured in neonates. Post-delivery, the women answered questions on SLEs during the pregnancy. Women reporting 1 or more SLEs during pregnancy were considered a "higher stressor" group, whereas women reporting no SLEs or who reported a SLE that was perceived as not at all stressful were considered a "lower stressor" group. Multivariable linear regression models were fit stratified by stressor group. Maternal stressor, AGD and phthalates results were available for 153 females and 147 males. A summary measure of androgen-disrupting phthalates (Σ AD) was associated with significantly longer AGDs in females from the higher stressor group. These effect sizes were increased when the perceived impact was restricted to moderately or very much stressful. In males, all phthalates were associated with longer anopenile distance (APD), regardless of stressor group; however, higher Σ AD was associated with significantly longer APD in the lower stressor group. In contrast to the TIDES study, we did not observe shorter AGDs in male infants prenatally exposed to di-(2-ethylhexyl) phthalates, regardless of maternal stressor level. In conclusion, we were unable to replicate the findings of the TIDES study, but did find some evidence that prenatal SLEs may modify associations between phthalates and female AGD. Further research with other populations and measures of prenatal stress may shed more light on whether prenatal stress is an important effect modifier of associations between phthalates (or other chemicals) and anogenital distance.


Assuntos
Malformações Anorretais/epidemiologia , Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/metabolismo , Ácidos Ftálicos/metabolismo , Estresse Fisiológico/fisiologia , Disruptores Endócrinos/metabolismo , Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mães , Ácidos Ftálicos/toxicidade , Gravidez , Primeiro Trimestre da Gravidez
11.
Biol Reprod ; 98(5): 623-633, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29385395

RESUMO

MicroRNA (miRNA), noncoding segments of RNA involved in post-transcriptional regulation of protein expression are differentially expressed in eutopic endometrium of women with and without endometriosis compared to endometriotic lesions. However, endometriotic lesion types are known to be biochemically distinct and therefore hypothesized that miRNAs are differentially expressed in endometriomas compared to peritoneal and deep-infiltrating lesions. Therefore, endometrial biopsies and ectopic implants from women (n = 38) undergoing laparoscopic surgery for chronic pelvic pain were collected. Samples of endometriomas, peritoneal or deep-infiltrating lesions were selected from our tissue bank for study participants who exclusively had only one lesion type noted on their surgical report. Quantitative real-time polymerase chain reaction for miR-9, miR-21, miR-424, miR-10a, miR-10b, and miR-204 was performed. miR-204 expression was significantly lower (P = 0.0016) in the eutopic endometrium of women with endometriosis compared to controls. Relative expression of miR-21, miR-424, and miR-10b differed significantly (P < 0.05) across endometriotic lesion types. Finally, all miRNAs isolated from endometriomas, peritoneal and deep-infiltrating lesions studied were differentially expressed compared to matched eutopic endometrium samples. We therefore conclude that miRNA expression in the eutopic endometrium from women with endometriosis differs from symptomatic controls. Moreover, miRNA expression pattern is dependent on the endometriotic lesion type studied. We suggest that identification of different miRNA expression patterns for endometriomas, peritoneal and deep-infiltrating lesions could contribute to individualized patient care for women with endometriosis.


Assuntos
Endometriose/metabolismo , Endométrio/metabolismo , MicroRNAs/metabolismo , Doenças Peritoneais/metabolismo , Adulto , Endometriose/genética , Endometriose/cirurgia , Endométrio/cirurgia , Feminino , Regulação da Expressão Gênica , Humanos , MicroRNAs/genética , Doenças Peritoneais/genética , Doenças Peritoneais/cirurgia
12.
J Appl Toxicol ; 38(5): 744-752, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29377183

RESUMO

Exposure to environmental toxicants has been associated with ovarian dysfunction yet sensitive biomarkers of adverse effect are lacking. We previously demonstrated that cigarette smoke exposure induced decreased relative ovarian weight, increased follicle loss and granulosa cell autophagy in mice. We postulate that cigarette smoke exposure will induce changes in the epigenome that can be used to reveal potential sensitive biomarkers of ovarian toxicity. Therefore, we evaluated differences in expression of 940 microRNAs (miRNAs), environmentally responsive small non-coding genes that regulate expression of genes at the post-transcriptional level, in ovarian tissue from 8-week-old female C57BL/6 mice exposed to room air or cigarette smoke 5 days per week for 8 weeks. A total of 152 miRNAs were dysregulated in expression, 17 of which were examined with quantitative polymerase chain reaction analysis. Using an online miRNA database tool, complete lists of predicted miRNA gene targets were generated, 12 of which were measured for their expression levels with quantitative polymerase chain reaction. An online bioinformatics resource database, DAVID generated functional classification lists of the target genes and their associated biological pathways. Results of the present pilot study suggest that miR-379, miR-15b, miR-691, miR-872 and miR-1897-5p are potentially useful markers of ovarian toxicity and dysfunction. Examination of the expression pattern of the target mRNA for these miRNA species demonstrated that cigarette smoke exposure induced significant changes that affect mitogen-activated protein kinase signaling pathways. We therefore suggest that miRNAs could serve as sensitive markers of ovarian toxicity and elucidate affected pathways.


Assuntos
MicroRNAs/metabolismo , Ovário/efeitos dos fármacos , Animais , Biomarcadores/metabolismo , Feminino , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Projetos Piloto , Reação em Cadeia da Polimerase em Tempo Real , Poluição por Fumaça de Tabaco/efeitos adversos
13.
Crit Rev Toxicol ; 47(1): 59-84, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27685638

RESUMO

Congenital anomalies are an important cause of infant mortality and disability. Developmental exposure to environmental contaminants is thought to increase the risk for congenital anomalies. Herein, we describe a critical review of the literature conducted between February and March 2014 yielding 3057 references from which 97 unique relevant articles published from 2003 through 2014 were evaluated. Common congenital anomalies including hypospadias, cryptorchidism, anogenital distance (AGD), congenital heart defects and oral clefts were well represented in the literature whereas other outcomes such as neural tube defects, limb deficiency defects and gastroschisis were rarely described. While definitions used for congenital anomalies and methods of ascertainment were usually consistent across studies, inconsistencies were frequently found in grouping of different congenital heart defects. Despite strong links between some congenital anomalies and parental occupation, these studies are unable to provide clear insight into the specific chemicals responsible owing to lack of direct measures of exposure. In comparison, data are mixed for contaminant exposures at concentrations representative of results from contemporary biomonitoring studies. Of the environmental contaminants studied, the association between phthalate exposures and developmental abnormalities of the male reproductive tract received the greatest attention. Important limitations of the literature studied relate to adequacy of sample size, absence of or weaknesses in exposure assessment methodologies, failure to account for biological plausibility and grouping of congenital anomalies with divergent mechanisms. We conclude that the literature is inadequate at this time to support a conclusion that exposure to environmental contaminants are or are not associated with increased risks for congenital anomalies in the general population.


Assuntos
Anormalidades Induzidas por Medicamentos/epidemiologia , Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/toxicidade , Monitoramento Ambiental , Humanos
14.
Environ Health ; 15(1): 59, 2016 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-27142700

RESUMO

BACKGROUND: Pregnant women are an especially important population to monitor for environmental exposures given the vulnerability of the developing fetus. During pregnancy and lactation chemical body burdens may change due to the significant physiological changes that occur. Developmental exposures to some persistent organic pollutants (POPs) have been linked with adverse health outcomes. METHODS: First trimester maternal and cord blood plasma concentrations of several POPs including polychlorinated biphenyls (PCBs), organochlorine pesticides (OCs), polybrominated diphenyl ethers (PBDE)s and perfluoroalkyl substances (PFASs) were measured in samples from 1983 pregnant women enrolled in the Maternal-Infant Research on Environmental Chemicals (MIREC) cohort. Predictors of exposure were also identified. RESULTS: In maternal plasma, there was >90 % detection for the perfluoroalkyl substances (PFASs) perfluorooctanoic acid (PFOA), perfluoroctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), and dichlorodiphenyldichloroethylene (DDE), oxychlordane and PCB 138 and 153. Cord blood plasma had much lower detection rates with low or very limited detection for most PCBs and PBDEs. The PFASs were the most frequently detected (23-64 %) chemical class in cord plasma. In a subset of 1st and 3rd trimester paired samples, PFAS concentrations were found to be strongly correlated and had ICCs ranging from 0.64 (PFOA) to 0.83 (PFHxS). The cord:maternal plasma concentration ratios ranged from 0.14 (PFOS) to 0.87 (oxychlordane, lipid adjusted). Similar to other studies, we found parity, maternal age, income, education, smoking status, pre-pregnancy BMI and fish consumption to be significant predictors for most chemicals. Those participants who were foreign-born had significantly higher concentrations of organochlorinated pesticides and PCBs. CONCLUSIONS: In the MIREC study, multiple chemical contaminants were quantified in the plasma of pregnant women. In cord plasma PFOA had the highest detection rate. However, compared to other Canadian and international population studies, the MIREC participants had lower contaminant concentrations of these substances.


Assuntos
Poluentes Ambientais/sangue , Sangue Fetal/química , Adulto , Ácidos Alcanossulfônicos/sangue , Canadá , Caprilatos/sangue , Cidades , Estudos de Coortes , Monitoramento Ambiental , Feminino , Fluorocarbonos/sangue , Éteres Difenil Halogenados/sangue , Humanos , Recém-Nascido , Masculino , Praguicidas/sangue , Bifenilos Policlorados/sangue , Gravidez
15.
J Appl Toxicol ; 36(9): 1235-45, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27135907

RESUMO

Parabens and phthalates are commercial chemicals widely used in the manufacture of industrial and consumer products frequently found as contaminants in biological fluids. We evaluated the effects of di-(2-ethylhexyl) phthalate (DEHP) (ranging from 10(-9) to 10(-7) m [1-100 nm; 0.39-39 ng ml(-1) ]) and butylparaben (BP) (ranging from 10(-8) to 10(-5) m [10 nm-10 µm; 1.9 ng ml(-1) to 1.9 µg ml(-1) ]), alone and in combination, on isolated mouse preantral follicle and human granulosa cell (hGC) cultures to study direct effects on follicle growth and ovarian steroidogenesis. Our results revealed that, in follicle culture, DEHP and BP attenuate estradiol output but only when present together. DEHP decreases progesterone concentrations in the spent media of hGC cultures, an effect that was attenuated when BP was added together with DEHP. Although changes in steroidogenesis were observed, no effects on follicular development or survival were noted in the culture systems. We suggest that BP and DEHP act with additive effect to decrease estradiol production whereas at later stages of follicle development BP blocks the effect of DEHP in hGCs resulting in decreased progesterone output. Taken together our results suggest that DEHP and BP adversely affect steroidogenesis from the preantral stage onward and the effects of these chemicals are both stage-dependent and modified by co-exposure. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Dietilexilftalato/toxicidade , Folículo Ovariano/efeitos dos fármacos , Parabenos/toxicidade , Animais , Células Cultivadas , Disruptores Endócrinos/toxicidade , Estradiol/metabolismo , Feminino , Células da Granulosa/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Folículo Ovariano/metabolismo , Progesterona/metabolismo
16.
Can J Diet Pract Res ; 77(3): 133-9, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27182607

RESUMO

PURPOSE: The aim was to validate a food frequency questionnaire (FFQ) against a 3-day food record (3DFR) for pregnant women with a focus on nutrients important for bone health from food and supplements. METHODS: The FFQ and 3DFR were administered to pregnant women (n = 42) aged 18-45 years in their third trimester of pregnancy in Hamilton, Ontario. Nutrient analysis of intakes was conducted using an FFQ calculator and Nutritionist-Pro software. The average daily serving consumption of Milk and alternatives group and Vegetable subgroup from Canada's Food Guide were also compared. RESULTS: There was a high positive correlation between methods for total dietary vitamin D (r = 0.83). Low positive associations were observed for total protein (r = 0.37), calcium (r = 0.36), vitamin K (r = 0.41), and servings of Milk and alternatives (r = 0.36). A cross-classification analysis using participants' intake quartiles revealed no major misclassifications. Bland-Altman analysis showed that the FFQ mildly underestimated the intake for protein, whereas it grossly overestimated the intake of vitamin K, and daily servings of Milk and alternatives and Vegetable. CONCLUSIONS: This FFQ can serve as a useful tool in clinical and research settings to assess key bone nutrients from foods and supplement sources in pregnant women.


Assuntos
Osso e Ossos/fisiologia , Registros de Dieta , Inquéritos sobre Dietas , Avaliação Nutricional , Necessidades Nutricionais , Adolescente , Adulto , Cálcio da Dieta/administração & dosagem , Dieta , Dieta Saudável , Proteínas Alimentares/administração & dosagem , Feminino , Promoção da Saúde , Humanos , Ontário , Gravidez , Vitamina D/administração & dosagem , Vitamina K/administração & dosagem , Adulto Jovem
17.
Biol Reprod ; 93(4): 93, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26377221

RESUMO

We previously demonstrated that cigarette smoke (CS) exposure decreases primordial follicle counts and induces autophagy in ovarian granulosa cells in preference to apoptosis. Therefore, the objective of this study was to investigate molecular targets underlying smoke-induced activation of the reparative autophagy pathway in the ovary. Briefly, ovarian homogenates were prepared from adult female mice exposed to mainstream CS twice daily for 8 wk, using a whole-body exposure system. A gene array revealed that CS exposure induced a greater than 2-fold significant increase in the expression of proautophagic genes Cdkn1b, Map1lc3a, Bad, and Sqstm1/p62. A significant increase in Prkaa2, Pik3c3, and Maplc31b expression, as well as a significant decrease in Akt1 and Mtor expression, was detected by quantitative PCR. The 5'-AMP-activated protein kinase catalytic subunit (AMPK) alpha1 + alpha2 and ATG7 protein expression was significantly increased, whereas AKT1, mTOR, CDKN1B/p27, and CXCR4 proteins were significantly decreased in CS exposed versus control ovaries. Up-regulation of AMPK alpha1 + alpha2, a known initiator of autophagic signaling, and ATG7 further suggests activation of the autophagy cascade. Two prosurvival factors, AKT and mTOR, were decreased in expression, an outcome that favors induction of the autophagy pathway, whereas decreased levels of CDKN1B is suggestive of cell cycle dysregulation. In summary, our data suggest that CS exposure induces ovarian follicle loss through induction of the autophagic cascade via the AMPK pathway together with inhibition of antiautophagic markers AKT and mTOR. We further postulate that toxicant-induced dysregulation of reparative autophagy is a novel pathway central to impaired follicle development and subfertility.


Assuntos
Proteínas Quinases Ativadas por AMP/biossíntese , Proteínas Quinases Ativadas por AMP/genética , Autofagia/efeitos dos fármacos , Nicotiana/química , Transdução de Sinais/genética , Fumaça/efeitos adversos , Produtos do Tabaco , Animais , Autofagia/genética , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Nível de Saúde , Camundongos , Camundongos Endogâmicos C57BL , Proteína Oncogênica v-akt/biossíntese , Proteína Oncogênica v-akt/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos
18.
Hum Reprod ; 30(4): 925-36, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25662808

RESUMO

STUDY QUESTION: Are brain-derived neurotrophic factor (BDNF) and its receptors, NTRK2, NGFR and SORT1, regulated by ovarian steroids in the uterus? SUMMARY ANSWER: BDNF and its low affinity receptor, nerve growth factor receptor (NGFR), are regulated by estradiol in the uterus. WHAT IS KNOWN ALREADY: Recent studies have revealed a central role for neurotrophins in placental development, endometrial stem cell neurogenesis, endometrial carcinoma and endometriosis. Complex signaling pathways involving BDNF and its receptors are regulated by ovarian hormones in the brain, however their expression and regulation in the uterus is poorly defined. STUDY DESIGN, SIZE, DURATION: This experimental animal study involved a total of 80 mice. PARTICIPANTS/MATERIALS, SETTING, METHODS: Female C57BL/6 mice (n = 50) were monitored daily for estrous cycle stage, and uterine horns were collected. A second group of mice (n = 30) were ovariectomized and given estradiol, progesterone, estradiol + progesterone, or saline for 4 days. Uterine expression of BDNF and its receptors were quantified by real-time PCR and western blot, and localized using immunohistochemistry. MAIN RESULTS AND THE ROLE OF CHANCE: During the estrous cycle, expression of BDNF, NTRK2 and SORT1 remained constant, while NGFR declined 11-fold from pro-estrus through to diestrus (P = 0.005). In ovariectomized mice, estradiol treatment increased uterine expression of mature BDNF greater than 6-fold (P = 0.013, 25 kDa; P = 0.003, 27 kDa), pro-BDNF 5-fold (P = 0.041, 37 kDa band; P = 0.046, 40 kDa band), and NGFR 5-fold (P < 0.001) when compared with other treatments. NTRK2 and SORT1 were unaffected by ovarian hormones. NGFR was primarily localized in epithelial cells in mice in diestrus or in ovariectomized mice treated with progesterone (P ≤ 0.001; P ≤ 0.001, respectively). In contrast, NGFR switched to a stromal localization in ovariectomized mice administered estradiol (P = 0.002). LIMITATIONS, REASONS FOR CAUTION: This study was performed in one only species. WIDER IMPLICATIONS OF THE FINDINGS: Results of this study demonstrate the uterine regulation of BDNF and NGFR by estradiol, and highlight the striking difference between hormone exposure during the estrous cycle and daily estradiol exposure after ovariectomy on neurotrophin expression in the uterus. The results also show the spatial regulation of NGFR in the uterus in response to ovarian hormones. Sustained estrogen exposure, as seen in estrogen-dependent disease, may alter the delicate neurotrophin balance and inappropriately activate potent BDNF-NTRK2 pathways which are capable of contributing to endometrial pathology. STUDY FUNDING/COMPETING INTERESTS: This study was supported by the Canadian Institutes of Health Research (CIHR) (W.G.F.), a NSERC Discovery Grant (W.G.F.), and a Vanier Canada Graduate Scholarship-CIHR (J.M.W.). J.M.W. is a member of the CIHR sponsored Reproduction and Early Development in Health training program. The authors declare no conflicts of interest.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Estrogênios/metabolismo , Regulação da Expressão Gênica , Ovário/metabolismo , Receptor trkB/metabolismo , Útero/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Estradiol/metabolismo , Estro , Feminino , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Crescimento Neural/metabolismo , Ovariectomia , Proteínas Tirosina Quinases/metabolismo , Transdução de Sinais , Células-Tronco/citologia , Esteroides/metabolismo
19.
Regul Toxicol Pharmacol ; 73(3): 754-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26550933

RESUMO

Recently Bergman et al. (2015) took issue with our comments (Lamb et al., 2014) on the WHO-UNEP(1) report entitled the "State of the Science of Endocrine Disrupting Chemicals - 2012" (WHO 2013a). We find several key differences between their view and ours regarding the selection of studies and presentation of data related to endocrine disrupting chemicals (EDCs) under the WHO-IPCS(2) definition (2002). In this response we address the factors that we think are most important: 1. the difference between hazard and risk; 2. the different approaches for hazard identification (weight of the evidence [WOE] vs. emphasizing positive findings over null results); and 3. the lack of a justification for conceptual or practical differences between EDCs and other groups of agents.


Assuntos
Disruptores Endócrinos/toxicidade , Animais , Humanos
20.
Crit Rev Toxicol ; 44(6): 467-98, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24903855

RESUMO

Phthalate diesters are a diverse group of chemicals used to make plastics flexible and are found in personal care products, medical equipment, and medication capsules. Ubiquitous in the environment, human exposure to phthalates is unavoidable; however, the clinical relevance of low concentrations in human tissues remains uncertain. The epidemiological literature was inadequate for prior reviews to conclusively evaluate the effects of phthalates on male reproductive tract development and function, but recent studies have expanded the literature. Therefore, we conducted a systematic review of the literature focused on the effects of phthalate exposure on the developing male reproductive tract, puberty, semen quality, fertility, and reproductive hormones. We conclude that although the epidemiological evidence for an association between phthalate exposure and most adverse outcomes in the reproductive system, at concentrations to which general human populations are exposed, is minimal to weak, the evidence for effects on semen quality is moderate. Results of animal studies reveal that, although DEHP was the most potent, different phthalates have similar effects and can adversely affect development of the male reproductive tract with semen quality being the most sensitive outcome. We also note that developmental exposure in humans was within an order of magnitude of the adverse effects documented in several animal studies. While the mechanisms underlying phthalate toxicity remain unclear, the animal literature suggests that mice are less sensitive than rats and potentially more relevant to estimating effects in humans. Potential for chemical interactions and effects across generations highlights the need for continued study.


Assuntos
Ácidos Ftálicos/toxicidade , Reprodução/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Poluentes Ambientais/toxicidade , Estudos Epidemiológicos , Humanos , Masculino , Análise do Sêmen/métodos
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