Rutin forestalls dysregulated cardiac bioenergetics in bisphenol A and dibutyl phthalate-exposed rats through PPAR? and AMPK modulation

Objectives: Proper cardiac function is greatly dependent on adequate supply and metabolism of energy substrates. Environmental pollutants exposure including plasticizers can trigger adverse cardiac metabolic events. This study was designed to investigate the ameliorative effect of rutin (Rt) on dysregulated cardiac energy metabolism in plasticizer-exposed rats. Materials and Methods: Forty-two rats were randomised into seven groups (n = 6): Control (0.1% dimethyl sulfoxide), bisphenol A (BPA, 25 mg/kg, p.o), dibutyl phthalate (DBP, 25 mg/kg, p.o), BPA + Rt 25 mg/kg, Rt 50 mg/kg, DBP + Rt (25 mg/kg, Rt 50 mg/kg), BPA + DBP and BPA + DBP + Rt, daily for 21 days. Results: BPA and DBP exposure increased plasma glucose, reduced insulin, and increased plasma and cardiac free fatty-acid. Cardiac glucose-6-phosphate level, hexokinase and pyruvate dehydrogenase activities increased in DBP while BPA reduced these variables. Cardiac glucose transporter-4 expression was reduced in BPA group, while cardiac peroxisome proliferator-activated receptor-alpha (PPAR?) and AMP-activated protein kinase (AMPK) expression increased in BPA and DBP-treated rats. However, Rt administration prevents impaired cardiac bioenergetics and glucometabolic regulation. Conclusion: Summarily, Rt improves BPA and DBP-impaired cardiac bioenergetics through PPAR? and AMPK modulation.

Research progress in detection method for bisphenol A in food packaging materials / 上海预防医学

As an industrial chemical， bisphenol A is widely used in various food packaging materials. However， it is an endocrine disrupting chemical， which has estrogen activity and can cause certain damage to humans. So far， there are few studies on the detection of bisphenol A in self-heating food packaging materials， and there remains a lack of relevant standard. Therefore， it is necessary to establish a simple， sensitive and efficient method for the detection of bisphenol A in self-heating food. This study briefly introduces the pretreatment methods of bisphenol A， such as ultrasonic extraction， solid phase extraction， accelerated solvent extraction， and detection methods， such as gas chromatography-mass spectrometry， high performance liquid chromatography， fluorescent detection， and electrochemical detection.

Advances in the effects of exposure to bisphenol A and its analogues during pregnancy on maternal and infant health / 国际儿科学杂志

Bisphenol A(BPA)as a typical environmental endocrine disruptor, has been widely used in daily consumer goods.It has reproductive, developmental, neurotoxicity and other biological toxicity, so it is gradually replaced by bisphenol F, bisphenol S, bisphenol AF and other analogues.Studies have shown that BPA and its analogues can enter the human body through many ways, have been detected in human blood, urine, placenta, breast milk, amniotic fluid and other tissue samples, and transmitted to the fetus, causing a variety of toxic effects, thus affecting the health of pregnant women and fetuses, and may lead to adverse pregnancy outcomes such as preterm delivery, abortion, low birth weight and so on.This article reviews the ways and current situation of exposure to BPA and its analogues during pregnancy in recent years, and its effects on maternal and fetal health, and puts forward reasonable suggestions for maternal and infant health from the point of view of exposure to adverse environmental factors, so as to provide inspiration for future research.

Mechanism of nephrotoxicity induced by chronic exposure of bisphenol A in mice based on oxidative stress and cell apoptosis / 生物工程学报

Bisphenol A (BPA) is widely used to produce epoxy resin and polycarbonate plastic products. In severe cases, these plastics may release BPA, which then infiltrates into the environment. Various concentrations of BPA have been found in most biological fluid. Its presence has been well shown to be closely related to many chronic diseases, including chronic kidney disease (CKD). However, little is known regarding the adverse effects of BPA exposure and its succedent cellular events on CKD. Hence, in the current in vivo study, we aimed to assess the effects of chronic exposure to BPA on animal nephrotoxicity through investigating oxidative stress and apoptosis. Upon exposure to BPA at 0.01, 0.1, and 1 mg/L via drinking water for four weeks, the mated and pregnant females were continuously exposed to BPA until weaning. Subsequently, three weeks old F1-male neonates were also orally challenged with the same three doses of BPA for ten weeks. The results showed that the kidneys of 0.1 and 1 mg/L BPA-treated mice were seriously damaged; the contents of serum renal function indexes and lipid peroxidation products were significantly increased, including urea nitrogen, creatinine, uric acid, and thiobarbituric acid reactive substances; the morphological structure of mouse kidneys was impaired; the expressions of antioxidant-related genes at mRNA and protein levels from mouse kidneys were markedly diminished, including glutathione-S-transferase, superoxide dismutase, and catalase; the expressions of genes and proteins related to apoptosis index (ratio of Bax/Bcl-1 and Caspase-3) were significantly enhanced. The data manifested that cumulative oxidative stress and apoptosis might play an essential role in the animal nephrotoxicity induced by chronic exposure to BPA.

Bisphenol A induces testicular oxidative stress in mice leading to ferroptosis / 亚洲男科学杂志(英文版)

Bisphenol A is a common environmental factor and endocrine disruptor that exerts a negative impact on male reproductive ability. By exploring bisphenol A-induced testicular cell death using the Institute of Cancer Research (ICR) mouse model, we found that a ferroptosis phenomenon may exist. Mice were divided into six groups and administered different doses of bisphenol A via intragastric gavage once daily for 45 consecutive days. Serum was then collected to determine the levels of superoxide dismutase and malondialdehyde. Epididymal sperm was also collected for semen analysis, and testicular tissue was collected for ferritin content determination, electron microscope observation of mitochondrial morphology, immunohistochemistry, real-time quantitative polymerase chain reaction, and western blot analysis. Exposure to bisphenol A was found to decrease sperm quality and cause oxidative damage, iron accumulation, and mitochondrial damage in the testes of mice. In addition, bisphenol A was confirmed to affect the expression of the ferroptosis-related genes, glutathione peroxidase 4 (GPX4), ferritin heavy chain 1 (FTH1), cyclooxygenase 2 (COX2), and acyl-CoA synthetase 4 (ACSL4) in mouse testicular tissues. Accordingly, we speculate that bisphenol A induces oxidative stress, which leads to the ferroptosis of testicular cells. Overall, the inhibition of ferroptosis may be a potential strategy to reduce male reproductive toxicity caused by bisphenol A.

Does bisphenol A (BPA) participates in the pathogenesis of Polycystic Ovary Syndrome (PCOS)?

Abstract PCOS is an endocrine disorder characterized by chronic anovulation, hyperandrogenism, and polycystic ovaries. Its etiology is uncertain. It is debated whether BPA would be a component of the environmental factor in the etiology of PCOS. Contamination by BPA can occur from food packaging (exposure during the diet) and through skin absorption and/or inhalation. It can be transferred to the fetus via the placenta or to the infant via breast milk, and it can be found in follicular fluid, fetal serum, and amniotic fluid. The phenolic structure of BPA allows it to interact with Estrogen Receptors (ERs) through genomic signaling, in which BPA binds to nuclear ERα or Erβ, or through nongenomic signaling by binding to membrane ERs, prompting a rapid and intense response. With daily and constant exposure, BPA's tendency to bioaccumulate and its ability to activate nongenomic signaling pathways can alter women's metabolic and reproductive function, leading to hyperandrogenism, insulin resistance, obesity, atherogenic dyslipidemia, chronic inflammatory state, and anovulation and favoring PCOS. The harmful changes caused by BPA can be passed on to future generations without the need for additional exposure because of epigenetic modifications. Not only high BPA levels can produce harmful effects, but at low levels, BPA may be harmful when exposure occurs during the most vulnerable periods, such as the fetal and neonatal periods, as well as during the prepubertal age causing an early accumulation of BPA in the body. Learning how BPA participates in the pathogenesis of PCOS poses a challenge and further studies should be conducted.

Principales disruptores endocrinos vinculados con salud reproductiva femenina: bases biológicas de su asociación / Main endocrine disruptors related to female reproductive health: biological basis of their association

Resumen Se denominan disruptores endocrinos (DEs) a aquellas sustancias químicas capaces de interferir con la homeostasis hormonal, alterando la síntesis, función, almacenamiento y/o metabolismo de las hormonas. Estas sustancias se encuentran en el ambiente y en una amplia variedad de productos de uso diario, por lo que la exposición humana es permanente. Experimentos con animales han confirmado la capacidad de los DEs para inducir desórdenes reproductivos, por lo que se ha sugerido que podrían ser un factor importante como causa de subfertilidad humana. El bisfenol A, los ftalatos y los compuestos orgánicos persistentes son tres tipos de DEs presentes en el medio ambiente y asociados con alteraciones reproductivas. Consultando las bases de datos MEDLINE y PubMed, en la presente revisión, se reúne bibliografía de los últimos 20 años donde se evalúan los efectos provocados por la exposición a los DEs mencionados en mujeres durante la vida adulta. Se resumen los efectos sobre marcadores de reserva ovárica y los resultados de tratamientos de fertilización in vitro. Por otro lado, se evalúa la evidencia a nivel molecular de los efectos provocados por los DEs sobre la fisiología reproductiva en estudios in vitro e in vivo.

Abstract Endocrine disruptors (EDs) are those chemical substances capable of interfering with hormonal homeostasis, altering the synthesis, function, storage and / or metabolism of hormones. These substances are found in the environment and in a wide variety of products for daily use, so human exposure is permanent. Animal experiments have confirmed the capacity of EDs to induce reproductive disorders, which is why it has been suggested that they could be an important factor in causing human subfertility. Bisphenol A, phthalates and persistent organic compounds are three types of EDs present in the environment and associated with reproductive disorders. Consulting the MEDLINE and PubMed databases, in this review, a bibliography of the last 20 years is gathered where the effects caused by exposure to the mentioned EDs in women during adult life are evaluated. The effects on ovarian reserve markers and the results of in vitro fertilization treatments are summarized. On the other hand, the evidence at the molecular level of the effects caused by EDs on reproductive physiology is evaluated in in vitro and in vivo studies.

A Study on the Parenting Styles and Parental Stress of Parents of (Attention Deficit Hyperactivity Disorder) ADHD Children

Background: There are several steps involved in deciding if a child has ADHD. No single test is available to diagnose ADHD and many other problems such as depression, anxiety, sleep problems and certain types of learning disabilities can also have similar symptoms. One of the process involves doing a medical examination, including hearing and vision tests, to rule out other problems with symptoms like ADHD. Diagnosis of ADHD includes a checklist for rating ADHD symptoms and taking a history of the child from parents, teachers, and sometimes, the child itself. Aim & Objectives: To know the prevalence of psychiatric co-morbidities in ADHD and to assess parental stress and parenting style among parents of children having ADHD.Material & Methods:A total of 78 children (6 to 18 years of age) and their parents were selected for the completion this study. The study was carried out in the Department of Psychiatry, Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi. Bivariate table and chi-square/Fisher Exact test were used. Correlation test has also been applied to know the association between demographic variables and their responses. Conclusions:We conclude that specific scales of the CBCL may help to identify specific comorbidities within ADHD cases in the primary care setting.

Research progress on reproductive toxicity and reproductive system tumors induced by environmental endocrine disrupting chemicals / 环境与职业医学

Environmental endocrine disrupting chemicals are a kind of exogenous chemicals that generally exist in the environment, and can disturb the endocrine homeostasis and adversely affect reproductive, immune, neurological, and other functions after entering the body, among which the damage to the reproductive system is the most significant one. Studies have confirmed that the long-term exposure to environmental endocrine disrupting chemicals have irreversible and harmful effects on primordial germ cell growth, reproductive organ development, and reproductive endocrine regulation, and also have obvious correlations with the occurrence and development of various reproductive system tumors. This paper reviewed various reproductive toxicities induced by common environmental endocrine disrupting chemicals in the developmental and reproductive stages, and associated mechanisms involved in the occurrence and development of reproductive system tumors.

Release of leachable products from resinous compounds in the saliva of children with anterior open bite treated with spur

Abstract To evaluate the release of bisphenol-A glycidyl methacrylate (BisGMA), triethylene glycol dimethacrylate (TEGDMA), bisphenol A (BPA), and phthalates of the composite resin used in the bonding of spurs applied in the treatment of children with anterior open bite and its effects on human keratinocytes. Methodology Saliva samples of 22 children were collected before spur attachment (baseline) and 30 minutes (min) and 24 hours (h) after spur bonding. Analysis was performed using high-performance liquid chromatography (HPLC) coupled to tandem mass spectrometry (HPLC-MS/MS) and gas chromatography coupled to mass spectrometry (GC-MS). Standardized resin increments were added to three different dilutions of the cell culture medium. Keratinocytes (HaCaT) were cultivated in the conditioned media and evaluated for cell viability (MTT) and cell scratch assay. Results The levels of BisGMA (1.74±0.27 μg/mL), TEGDMA (2.29±0.36 μg/mL), and BPA (3.264±0.88 μg/L) in the saliva after 30 min, in comparison to baseline (0±0 μg/mL, 0±0 μg/mL, and 1.15±0.21 μg/L, respectively), presented higher numbers. After 24 h, the levels of the monomers were similar to the baseline. Phthalates showed no significant difference among groups. HaCat cells showed increased viability and reduced cell migration over time after exposure to methacrylate-based resin composites. Conclusion Resin composites, used to attach spurs in children with anterior open bite during orthodontic treatment, release monomers after polymerization and can influence the behavior of human keratinocytes, even at very low concentrations. Orthodontists should be aware of the risks of the resinous compounds release and preventive procedures should be held to reduce patient exposure.

Effects of bisphenol A exposure at different circadian time on hepatic lipid metabolism in mice / 环境与职业医学

Background Lipid metabolism in liver shows circadian-dependent profiles. The hepatotoxicity of environmental chemicals is dependent on circadian time. Objective To observe the effects of bisphenol A (BPA) exposure at different zeitgeber time (ZT) on hepatic and blood lipid metabolism and decipher the underlying mechanisms related to circadian rhythm in mice. Methods Thirty-five female C57BL/6J mice were sacrificed every 4 h in a light-dark cycle (12 h/12 h). The liver tissues were collected to describe the circadian profiles of hepatic Rev-erba, Bmal1, Clock, Srebp1c, and Chrebp mRNA expression levels within 24 h. Thirty female mice were divided into 6 groups by the timing (ZT3 represents the 3 h after light on, ZT15 represents the 3 h after light off) and dose (50 or 500 μg·kg−1·d−1) of BPA exposure to observe hepatotoxicity. Mice were gavaged with designed doses of BPA once per day for 4 weeks. Mice were maintained with ad libitum access to food and water and measured body weight weekly. After the experiment, mice were euthanatized and liver tissues were separated to determine the biochemical indicators of lipid metabolism and lipid metabolism- and circadian-related gene mRNA expressions. Results Hepatic Rev-erba, Bmal1, Clock, Srebp1c, and Chrebp mRNA expression levels were rhythmic during a 24 h period in mice. At ZT3 and ZT15, BPA did not alter body weight, plasma glucose, plasma total cholesterol, plasma low density lipoprotein cholesterol, and plasma triglycerides (P>0.05). The plasma high density lipoprotein cholesterol decreased in the 50 μg·kg−1·d−1 BPA group at ZT3 by 14.56% compared with the control group (P<0.05). The liver triglycerides increased in the 50 μg·kg−1·d−1 BPA group at ZT15 by 115.20% compared with the control group (P<0.05). BPA decreased Srebp1c mRNA expression level when dosing at ZT3 and increased Chrebp, Srebp1c, and Acc1 mRNA expression levels when dosing at ZT15 compared with the control group (P<0.05). BPA increased Bmal1 mRNA expression level and decreased Rev-erbα mRNA expression level at ZT3 exposure and decreased Bmal1 and increased Rev-erbα mRNA expression level at ZT15 exposure (P<0.05). Conclusion BPA exposure at light or dark period has different effects on hepatic lipid metabolism in mice. Hepatic lipid deposit appears when BPA is dosed at dark period. Rev-erbα-Bmal1 regulation circuits and the subsequent upregulation of Srebp1c and Chrebp and the target gene Acc1 may be involved.

Determination of bisphenol A in water by truncated aptamer-fluorescence method / 预防医学

Objective@#To establish a fluorescence method based on turncated aptamer for the determination of bisphenol A in water.@*Methods@#The bisphenol A truncated aptamer containing 38 bases was selected as a recognition module, and was modified with the fluorophore 6-FAM at the 5'end. The 3'end of the complementary sequence cDNA was modified with the quencher DABCYL. The standard solutions of bisphenol A and interfering compounds were configured. The detection system was established after optimizing the number of bases in cDNA, the concentration ratio of truncated aptamer to cDNA, the incubation temperature and time, and the pH of the buffer. The specificity and recovery experiments were carried out. @*Results@#When the complementary sequence cDNA included 9 bases, the concentration ratio of the truncated aptamer to cDNA was 1:1.5, the pH value of the buffer solution was 7.5, the cDNA was incubated at 55 ℃ for 60 minutes, in the concentration range of 10-75 pmol/L, the linear regression equation was y=2 230.7x+110 825, the correlation coefficient was 0.926. The limits of detection was 3.3 pmol/L. The difference values of fluorescence intensity between tetrabromobisphenol A, estradiol, estriol, bisphenol S and bisphenol A were obviously different, so there was no significant interference to the test result. The recovery rates were 97.8%, 98.8% and 102.3% with the spiked concentrations of 20.0, 40.0 and 60.0 pmol/L. The relative standard deviations were 4.4%, 2.1% and 2.6% (n=5), respectively. @*Conclusion@#The fluorescence method based on turncated aptamer has the advantages of easy operation, high sensitivity and specificity, which can be used for the determination of bisphenol A in water.

Effects of bisphenol A on apoptosis of ovarian preantral follicular granulosa cells and ovarian development in mice / 南方医科大学学报

OBJECTIVE@#To investigate the effect of environmental estrogen bisphenol A (BPA) exposure on apoptosis of mouse ovarian preantral follicular granulosa cells and ovarian development and explore the underlying mechanism.@*METHODS@#Mouse ovarian preantral follicular granulosa cells were isolated from female ICR mice at postnatal day (PND) 10 and cultured @*RESULTS@#Compared with the control cells group, the isolated cells exposed to a low concentration of BPA (50 μmol/L) showed a significantly lowered apoptosis rate, increased mitochondrial membrane potential, and enhanced cellular proliferation (@*CONCLUSIONS@#BPA can concentration-dependently regulate the function of ovarian preantral follicular granulosa cells in mice and potentially affects both the pregnant mice and the offspring female mice in light of early ovarian development.

Associations between urinary bisphenol A concentrations during pregnancy and gestational age / 上海预防医学

Objective We aimed to assess the association between urinary bisphenol A(BPA)concentrations and gestational age in pregnant women. Methods A total of 248 pregnant women were recruited from a maternal and child care hospital in Shanghai. A questionnaire survey was completed to collect socio-demographic information and spot urine samples were collected during pregnancy. Gas chromatography-tandem mass spectrometry(GC-MS/MS)was used to measure BPA concentrations in urine samples. Linear relationship between urinary BPA level and gestational age was assessed by using generalized additive models. Multivariate regression model was used to evaluate associations of prenatal BPA exposure with gestational age. Results BPA was detected in all the urine samples. Median value and geometric mean of urinary BPA levels were 0.85 μg/L and 1.21 μg/L, respectively. Linear relationship between urinary BPA concentration and gestational weeks was confirmed(non-linear P > 0.05). Positive association between urinary BPA level and gestational age was indicated(regression coefficient, β = 0.19;95%CI:0.04-0.35;P = 0.016). However, it was only observed in girls, stratified by sex of newborns(β = 0.18;95%CI:0.03-0.34;P = 0.020). After stratification by trimester, no significant association was found in the second or the third trimesters. Conclusion Pregnant women are extensively exposed to BPA. Urinary BPA exposure during pregnancy may extend gestational age, especially in girls.

The effects of photoperiodism and exposure to bisphenol A on hepatic lipid metabolism in female mice / 中国职业医学

OBJECTIVE: To analyze the effects and the underlying mechanisms of photoperiodism and exposure to bisphenol A(BPA) on hepatic lipid metabolism in female mice. METHODS: A 2×2 factorial design was used. The photoperiod factor was set to fixed and shifted photoperiod, and the BPA factor was set to BPA exposure(BPA group) and non-exposure(control group). Specific pathogen free female C57 BL/6 J mice were randomly divided into four groups: fixed photoperiod control group, shifted photoperiod control group, fixed photoperiod BPA group, and shifted photoperiod BPA group, with eight rats in each group. The fixed photoperiod mice received a 12 ∶12 hours light-dark cycle, and the shifted photoperiod mice experienced reversed light-dark cycle once a week. Mice in BPA group were administered a dose of BPA 50 μg/kg body weigh by gavage, while mice in control group were given a equal volume of corn oil, once per day, five days per week for 12 weeks. The body weight of mice was measured during the experiment. After 12 weeks, all mice in each group were sacrificed. Plasma was collected and the levels of biochemical parameters were measured. Liver tissues were separated for examination of lipid deposition using oil red O and hematoxylin-eosin staining, and plasma triglyceride levels were measured. Real-time fluorescence quantitative polymerase chain reaction was used to detect the mRNA relative expression of genes of fat metabolism in liver tissues. RESULTS: At the end of the experiment, the body weights of mice were higher than that before the experiment(all P<0.05), but there was no statistically significant difference in body weights among the four groups(all P>0.05). The levels of plasma glucose, triglyceride and activity of alanine aminotransferase were higher in shifted photoperiod mice than that in the fixed photoperiod mice(all P<0.05). The plasma aspartate transaminase level was higher in BAP group than that in control group(P<0.01). The area of lipid staining in hepatic tissue was larger in the shifted photoperiod control group, fixed photoperiod BPA group and shifted photoperiod BPA group(all P<0.05), and hepatic lipid droplets aggregation was increased in these three groups compared with the fixed photoperiod control group. The mRNA relative expression of acetyl-coenzyme A carboxylase alpha(Acaca) was higher in the fixed photoperiod BPA and shifted photoperiod control groups(all P<0.05), compared with the fixed photoperiod control group. The relative expression of Acaca mRNA was lower in the shifted photoperiod BPA group than that in the fixed photoperiod BPA group(P<0.05). The mRNA relative expression of sterol regulatory element binding protein(Srebp) 1 and Srebp2 were significantly higher in the BPA group than that in the control group(all P<0.05). CONCLUSION: Both the single shifted photoperiod or BPA exposure can increase hepatic lipid deposition in female mice. The mechanism may be related to up-regulation of the mRNA expression of Acaca, Srebp1 and Srebp2. The shifted photoperiod in combination of BPA exposure has an antagonistic effect on the expression of Acaca mRNA in liver tissues of female mice.

The association between urinary bisphenol A levels and nonalcoholic fatty liver disease in Korean adults: Korean National Environmental Health Survey (KoNEHS) 2015-2017

BACKGROUND@#Nonalcoholic fatty liver disease (NAFLD) is becoming a global health problem. Bisphenol A (BPA), one of most widely used environmental chemicals, is suspected to be a contributor to the development NAFLD. This study was performed to examine the relationship between human BPA levels and risk of NAFLD.@*METHODS@#The data (n = 3476 adults: 1474 men and 2002 women) used in this study were obtained from the Korean National Environmental Health Survey III (2015-2017). BPA levels were measured in urine samples. NAFLD was defined using hepatic steatosis index after exclusion of other causes of hepatic diseases.@*RESULTS@#There was a significant linear relationship between the elevated urinary BPA concentrations and risk of NAFLD. In a univariate analysis, odds ratio (OR) of the highest quartile of urinary BPA level was 1.47 [95% confidence interval (CI) 1.11-1.94] compared to the lowest quartile. After adjusted with covariates, the ORs for NAFLD in the third and fourth quartiles were 1.31 [95% CI 1.03-1.67] and 1.32 [95% CI 1.03-1.70], respectively.@*CONCLUSIONS@#Urinary BPA levels are positively associated with the risk of NAFLD in adults. Further experimental studies are needed to understand the molecular mechanisms of BPA on NAFLD prevalence.

Antioxidant activity of selenium on bisphenol-induced apoptosis and testicular toxicity of Albino rats / Actividad antioxidante el selenio sobre la apoptosis inducid por bisfenol y toxicidad testicular en ratas albinas

SUMMARY: Bisphenol A (BPA) is an industrial chemical widely used to make polycarbonate plastics for packaging and epoxy resins. This study sought to examine how selenium (Se) affects BPA toxicity in terms of albino rats' histological structure, antioxidant enzymes and reproductive organs (seminiferous tubules). Twenty-four adult male rats were divided into four experimental groups: Group 1: Control; Group 2: Orally administered BPA; Group 3: Orally administered sodium selenite; Group 4: Treated daily with BPA followed by selenium (Se). All experiment done for 4 weeks. BPA exposure caused changes in the testicular histological structure, which consists apoptosis, and led to changes in several biochemical markers: Malondialdehyde, catalase, superoxide dismutase, and glutathione peroxidase. However, these BPA side effects may be ameliorated in rats treated with BPA-plus-Se. These protective effects of Se may attributable to its ability to remove potentially damaging oxidizing agents in living organisms. The results may confirm that Se countered the oxidant effects and increased the BPA-induced stress response in rats. So, Se promotes the healthy growth and development of mammals by protecting them from oxidative stress. As human are greatly exposed to BPA and it can accumulate in tissues, there is concern about human reproductive functions particularly for occupational workers exposed usually to greater levels of BPA. Thus, the use of BPA in multiple industries must be restricted and the inaccurate usage of plastic containers should be avoided to decrease the health hazards. Administration of Se may protect against the adverse effects of BPA on reproductive functions and structures.

RESUMEN: El bisfenol A (BPA) es un químico industrial ampliamente utilizado para fabricar plásticos de policarbonato para envases y resinas epoxi. Este estudio examinó el efecto de selenio (Se) en la toxicidad del BPA en términos de la estructura histológica, enzimas antioxidantes y los órganos reproductivos (túbulos seminíferos) de ratas albinas. Se dividieron veinticuatro ratas macho adultas en cuatro grupos experimentales: Grupo 1: control; Grupo 2: BPA administrado por vía oral; Grupo 3: BPA administrado por vía oral para; Grupo 4: tratado diariamente con BPA seguido de selenio (Se). El experimento se realizó durante cuatro semanas y se observó que la exposición al BPA provocó cambios en la estructura histológica testicular, incluyendo apoptosis, y alteraciones en varios marcadores bioquímicos:malondialdehído, catalasa, superóxido dismutasa y glutatión peroxidasa. Sin embargo, estos efectos secundarios del BPA pueden mejorar en ratas tratadas con BPA-plus-Se. Estos efectos protectores del Se pueden ser atribuidos a la capacidad de eliminar agentes oxidantes potencialmente dañinos en organismos vivos. Los resultados indicaron que se contrarrestaron los efectos oxidantes y aumentó la respuesta al estrés inducido por BPA en ratas, y favorece el crecimiento y desarrollo en los mamíferos al protegerlos del estrés oxidativo. Debido a la exposición al BPA en el ser humano, se puede acumular en los tejidos, por lo que existe una preocupación por el daño a las funciones reproductivas en particular de los trabajadores que generalmente están expuestos a niveles más altos de BPA. Por lo tanto, se debe restringir el uso de BPA en las industrias y evitar el uso incorrecto de envases de plástico para así disminuir los riesgos para la salud. La administración correcta de Se puede proteger contra los efectos adversos del BPA en las funciones y estructuras reproductivas.

Influence of Different Surface Treatments on the Bond Strength Between Composites and Resin Cement / INFLUÊNCIA DE DIFERENTES TRATAMENTOS DE SUPERFÍCIE NA RESISTÊNCIA DE UNIÃO ENTRE COMPÓSITOS E CIMENTO RESINOSO

The aim of this study was to evaluate the influence of different surface treatments on bond strength (BS) between composite and a resin cement trough microshear bond strength test. Seventy five discs (10x2 mm) of Filtek P90, Filtek Z250 and Filtek Z350 XT (3M ESPE), were divided into 5 groups according to the treatment: C= control - no treatment; sandblasting J= aluminum oxide (50µm); sandblasting JE = + 99.3% ethanol for 5 min; silica coating S = (3M-ESPE Cojet - 30 microns); SS = silica coating + silane. PVC tubes (0.5 x 0.80 mm) were attached on the composite disc, and then, inserted resin cement (3M ESPE-RelyX ARC). After 24 hours artificial saliva storage at 37oC, the specimens were tested for microshear crosshead speed of 1.0 mm/min. Data were evaluated in two-way ANOVA and Tukey's test (5%) for contrast. The results showed that sandblasting with aluminum oxide (J) was efficient in increasing the BS for composites Z350 and P90. For the Z250, there were no difference between treatments. Also, CS showed results similar to controls for all composites. SE showed the worst results for Z350 e P90. BS values were dependent on the type of composite and the surface treatment used. Sandblasting with aluminum oxide seems to be an effective surface treatment for composites and may lead to higher BS values, while the use of ethanol could be harmful.

O objetivo deste estudo foi avaliar a influência de tratamentos de superfície na resistência de união (RU) entre compósitos e um cimento resinoso. Setenta e cinco discos (10x2 mm) das resinas Filtek P90, Filtek Z250 e Filtek Z350 (3M ESPE) foram divididos em 5 grupos de acordo com o tratamento: N= sem tratamento; S= jateamento com óxido de alumínio (50µm); SE= jateamento de óxido de alumínio + 99,3% de etanol por 5 min; C= jateamento de sílica com Cojet - 30 microns (3M ESPE); CS= jateamento de sílica + silano. Tubos de PVC (0,5 x 0,80 mm) foram fixados nos discos e o cimento resinoso (RelyX ARC, 3M ESPE) foi inserido. Após 24 horas de armazenamento em saliva artificial a 37oC, os espécimes foram submetidos ao teste de microcisalhamento com velocidade de 1,0 mm/min. Os dados foram avaliados em ANOVA de dois fatores e no teste de Tukey (5%) para contraste. Os resultados mostraram que o tratamento com oxido de alumínio (J) foi eficiente no aumento da RU nos compósitos Filtek Z350 e P90. Não houve diferença entre tratamentos para a Z250. Grupo CS mostrou resultados semelhantes aos do controle para todos os compósitos. Já o SE mostrou os piores resultados de RU. Concluiu-se que os valores de RU foram dependentes do tipo de compósito e do tratamento de superfície utilizado. O jateamento com óxido de alumínio parece ser um tratamento de superfície eficaz e pode elevar os valores de RU, já o uso de etanol pode ser prejudicial

Comparative Study of Bisphenol A Release from Various Orthodontic Adhesive and Myofunctional Appliances - An In-Vitro Study.

We wanted to compare & evaluate, regularly used orthodontic materials including adhesives & myofunctional appliances for release of Bisphenol A. MethodsBisphenol - A release was assessed from two materials - orthodontic adhesive resin and heat cure acrylic resin [twin block]. Based on materials used, a total of 40 samples was assigned into two groups; Group A and Group B, each containing 20 samples. For Group A [orthodontic adhesive resin], metal brackets were bonded to 20 bicuspid teeth using adhesive resin and cured with LED light. For group B, 20 twin block appliances made from heat cured acrylic resin were used. Then, samples from both the groups were immersed in artificial saliva and then subjecting to thermal treatment from hot (60 ˚C) to cold (4 ˚C) temperatures, followed by shaking for 5 minutes. The samples were again shaken at (37 ˚C) and 1.0-mL aliquots were removed at 24 hours and 7 days after insertion. Gas chromatography / mass spectroscopy was used for the evaluation of leaching of bisphenol A from artificial saliva. ResultsSignificant results were found after 24 hours of analysis in both groups where 70 % samples from group A had bisphenol A release, whereas 80 % samples from group B had bisphenol A release. However, a non-significant result was obtained after 7 days where 20 % samples from group A had bisphenol A release whereas 60% samples from group B had bisphenol A release. The Heat cure acrylic group showed higher Bisphenol - A than that of orthodontic adhesive resin group. It was seen that the levels were lower than the reference dose which were calculated for daily consumption but were statistically significant. CoclusionsBisphenol A is considered as an endocrine disruptor. Degradation of orthodontic materials results in leaching of Bisphenol-A into oral cavity which is a clinical concern.

Endocrine disruption and infertility: Circulatory hormone and bisphenol A concentrations in infertile Saudi women

Aim: Human infertility is a public problem and a cause of social and psychological complications affecting more than 50 million couples globally. Bisphenol A (BPA) is a ubiquitous environmental endocrine disrupting chemical and has been associated with infertility problems in women.The aim of the present study was to analyze concentrations of bisphenol A and circulating hormones in infertile Saudi women for evaluating the association of BPA with infertility.Methodology: The present study was done on 43 infertile women for evaluating possible association of systemic BPA concentrations with infertility in Saudi Arabia. The clinical indications were irregular menses, hyper-androgenism, multiple small ovarian cysts, polycystic ovarian syndrome and unexplained infertility. Blood samples from infertile women and a control group of 18 healthy fertile women were analyzed and compared for concentrations of BPA and circulatory hormones. Results: The results showed that BPA concentrations were not significantly different between infertile women and controls. BPA concentrations were also not correlated with systemic hormone concentrations in infertile women. Interpretation: Serum BPA levels had no association with hormone imbalance in this cohort of infertile Saudi women. However, considering the previous studies that have shown a relationship of BPA with female infertility, an argument can be made that there might be lower exposure of Saudi population to BPA in comparison to BPA analogues such as BPS (according to recent reports). Therefore, it is suggested to conduct more infertility studies that include detection of BPA and its analogues in infertile Saudi women