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Diisobutyl Phthalate (DIBP) Final

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Journal Article
Journal Article

Chemical characterization, antioxidant and inhibitory effects of some marine sponges against carbohydrate metabolizing enzymes

Authors: Shaaban, M; Abd-Alla, HI; Hassan, AZ; Aly, HF; Ghani, MA (In Press) . HERO ID: 1292151

[Less] ABSTRACT: The present research was performed to investigate the effects of the extracts of four marine . . . [More] ABSTRACT: The present research was performed to investigate the effects of the extracts of four marine sponges on some biochemical parameters including antioxidant and three different carbohydrate hydrolyzing enzymes: alpha-Amylase, beta-galactosidase and alpha-glucosidase. The sponges were collected from Red Sea at Egyptian coasts, and taxonomically belonged to the genus of Smenospongia (SP1), Callyspongia (SP2), Niphates (SP3) and Stylissa (SP4), respectively. The sponges extracts exhibited diverse inhibitory effects on oxidative stress indices and carbohydrate hydrolyzing enzymes in linear relationships to some extent with concentration of inhibitors (dose dependant). The extracts of sponges (3, 1 and 2) showed, respectively, potent reducing power. Chemical characterization of sponge 1 recognized the existence of di-isobutyl phthalate (1), di-nbutyl phthalate (2), linoleic acid (3), beta-sitosterol (4) and cholesterol (5), while sponge 3 produced bis-[2-ethyl]-hexyl-phthylester (6) and triglyceride fatty acid ester (7).

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Effect of aminosilane compounds as external donors on isospecific polymerizations of 1-butene with MgCl2/TiCl4/DIBP catalyst

Authors: Yan, Y; Ren, H; Li, L; Xu, Y (2017) Catalysis Letters 147:221-227. HERO ID: 3859037

[Less] Four aminosilane compounds were synthesized and employed as external electron donors for 1-butene polymerization . . . [More] Four aminosilane compounds were synthesized and employed as external electron donors for 1-butene polymerization with MgCl2 supported Ziegler-Natta catalyst. The four aminosilane compounds are di(piperidinyl)dimethoxysilane (DPPDMS), di(piperidinyl)- diethoxysilane (DPPDES), di(pyrrolidinyl)dimethoxysilane (DPRDMS) and di(pyrrolidinyl)- diethoxysilane (DPRDES). A detailed study has been performed on the effects of the chemical structure of different external electron donors on the catalytic efficiency, isotacticity, melting temperature and molecular weight distribution of obtained poly(1-butene). Poly(1-butene) products have been characterized with gel permeation chromatography (GPC) and differential scanning calorimetry (DSC) analysis. The results indicated that: first, aminosilane compounds with dimethoxy groups showed higher catalytic efficiency and polymers isospecificity than those of with diethoxy groups. Conversely, the aminosilane compounds with diethoxy groups were conductive to obtaining polymers with broader molecular weight distribution than those of with dimethoxy groups. Second, compared with single DPPDMS or TEOS (tetraethyl orthosilicate), DPPDMS/TEOS complex in a proper molar ratio would not only increase the catalytic efficiency and isotacticity of obtained polymers, but also broaden the molecular weight distribution of polymers. Third, the effects of other factors on catalytic efficiency and isotacticity of polymers product were also studied, including different amount of hydrogen, concentration of external donor and cocatalyst.



Di(piperidinyl)dimethoxysilane (DPPDMS) was synthesized and employed as external electron donors for 1-butene polymerization with MgCl2 supported Ziegler-Natta catalyst. Compared with single DPPDMS or TEOS (tetraethyl orthosilicate), DPPDMS/TEOS complex in a proper molar ratio would not only increase the catalytic efficiency and isotacticity of obtained polymers, but also broaden the molecular weight distribution of polymers. The selection of molar ratio should depend on the requirements to the polymer.



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Journal Article
Journal Article

Doubly nonparametric sparse nonnegative matrix factorization based on dependent Indian buffet processes

Authors: Xuan, J; Lu, J; Zhang, G; Xu, RYD; Luo, X (2017) . HERO ID: 3859070

[Less] Sparse nonnegative matrix factorization (SNMF) aims to factorize a data matrix into two optimized nonnegative . . . [More] Sparse nonnegative matrix factorization (SNMF) aims to factorize a data matrix into two optimized nonnegative sparse factor matrices, which could benefit many tasks, such as document-word co-clustering. However, the traditional SNMF typically assumes the number of latent factors (i.e., dimensionality of the factor matrices) to be fixed. This assumption makes it inflexible in practice. In this paper, we propose a doubly sparse nonparametric NMF framework to mitigate this issue by using dependent Indian buffet processes (dIBP). We apply a correlation function for the generation of two stick weights associated with each column pair of factor matrices while still maintaining their respective marginal distribution specified by IBP. As a consequence, the generation of two factor matrices will be columnwise correlated. Under this framework, two classes of correlation function are proposed: 1) using bivariate Beta distribution and 2) using Copula function. Compared with the single IBP-based NMF, this paper jointly makes two factor matrices nonparametric and sparse, which could be applied to broader scenarios, such as co-clustering. This paper is seen to be much more flexible than Gaussian process-based and hierarchial Beta process-based dIBPs in terms of allowing the two corresponding binary matrix columns to have greater variations in their nonzero entries. Our experiments on synthetic data show the merits of this paper compared with the state-of-the-art models in respect of factorization efficiency, sparsity, and flexibility. Experiments on real-world data sets demonstrate the efficiency of this paper in document-word co-clustering tasks.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Urinary levels of phthalate metabolites and associations with demographic characteristics in Korean adults

Authors: Lee, KM; Kho, Y; Kim, PG; Park, SH; Lee, JH (2017) Environmental Science and Pollution Research 24:14669-14681. HERO ID: 3859032

[Less] The objective of this study is to assess human exposure to phthalates and its associations with demographic . . . [More] The objective of this study is to assess human exposure to phthalates and its associations with demographic characteristics of the subjects in the Korean National Human Biomonitoring Survey. The subjects aged between 18 and 69 were selected through nationwide stratified sampling. A total of 1874 urine samples were collected and stored at -20 °C until measurement for ten selected metabolites of phthalates (MnBP, MiBP, MBzP, MCHP, MnOP, MEHP, MEOHP, MEHHP, MiNP, and MiDP) using high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). The difference in the level of urinary phthalate metabolites by the characteristics of the subjects was tested for statistical significance using SAS Surveyreg procedure. The coefficients and standard errors from multiple linear regressions were exponentiated to estimate the adjusted proportional change (APC) and 95% CIs compared with a referent level. The proportion of data above LOQ was less than 20% for MCHP, MnOP, MiNP, and MiDP. Geometric means of creatinine-adjusted concentrations (unit: μg/g creatinine) of six other phthalate metabolites among Korean adults were 41.7 (95% CI 39.6-43.9) for MnBP, 17.1 (95% CI 16.1-18.1) for MiBP, 15.7 (95% CI 14.4-17.1) for MBzP, 8.65 (95% CI 8.10-9.22) for MEHP, 17.5 (95% CI 16.8-18.3) for MEOHP, and 38.1 (95% CI 36.2-40.2) for MEHHP. Urinary level of phthalates tended to be higher among subjects with older age, females, and those with vigorous daily physical activity and tended to be lower among drinkers and those with higher income. Our results suggest that the level of phthalate exposure is significant among Korean adults and thus warrants further studies to identify major source and route of exposure to phthalates.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Maternal urinary phthalates and sex-specific placental mRNA levels in an urban birth cohort

Authors: Adibi, JJ; Buckley, JP; Lee, MK; Williams, PL; Just, AC; Zhao, Y; Bhat, HK; Whyatt, RM (2017) Environmental Health: A Global Access Science Source 16:35. HERO ID: 3859023

[Less] BACKGROUND: Prenatal urinary concentrations of phthalates in women participants in . . . [More] BACKGROUND: Prenatal urinary concentrations of phthalates in women participants in an urban birth cohort were associated with outcomes in their children related to neurodevelopment, autoimmune disease risk, and fat mass at 3,5,7, and 8 years of life. Placental biomarkers and outcomes at birth may offer biologic insight into these associations. This is the first study to address these associations with candidate genes from the phthalate and placenta literature, accounting for sex differences, and using absolute quantitation methods for mRNA levels.

METHODS: We measured candidate mRNAs in 180 placentas sampled at birth (HSD17B1, AHR, CGA, CYP19A1, SLC27A4, PTGS2, PPARG, CYP11A1) by quantitative PCR and an absolute standard curve. We estimated associations of loge mRNA with quartiles of urinary phthalate monoesters using linear mixed models. Phthalate metabolites (N = 358) and mRNAs (N = 180) were transformed to a z-score and modeled as independent, correlated vectors in relation to large for gestational age (LGA) and gestational diabetes mellitus (GDM).

RESULTS: CGA was associated with 4 out of 6 urinary phthalates. CGA was 2.0 loge units lower at the 3(rd) vs. 1(st) quartile of mono-n-butyl phthalate (MnBP) (95% confidence interval (CI): -3.5, -0.5) in male placentas, but 0.6 loge units higher (95% CI: -0.8, 1.9) in female placentas (sex interaction p = 0.01). There was an inverse association of MnBP with PPARG in male placentas (-1.1 loge units at highest vs. lowest quartile, 95% CI: -2.0, -0.1). CY19A1, CYP11A1, CGA were associated with one or more of the following in a sex-specific manner: monobenzyl phthalate (MBzP), MnBP, mono-iso-butyl phthalate (MiBP). These 3 mRNAs were lower by 1.4-fold (95% CI: -2.4, -1.0) in male GDM placentas vs. female and non-GDM placentas (p-value for interaction = 0.04). The metabolites MnBP/MiBP were 16% higher (95% CI: 0, 22) in GDM pregnancies.

CONCLUSIONS: Prenatal concentrations of certain phthalates and outcomes at birth were modestly associated with molecular changes in fetal placental tissue during pregnancy. Associations were stronger in male vs. female placentas, and associations with MnBP and MiBP were stronger than other metabolites. Placental mRNAs are being pursued further as potential mediators of exposure-induced risks to the health of the child.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

The cave microbiome as a source for drug discovery: Reality or pipe dream?

Authors: Ghosh, S; Kuisiene, N; Cheeptham, N (2017) Biochemical Pharmacology 134:18-34. [Review] HERO ID: 3483282

[Less] This review highlights cave habitats, cave microbiomes and their potential for drug discovery. Such . . . [More] This review highlights cave habitats, cave microbiomes and their potential for drug discovery. Such studies face many challenges, including access to remote and pristine caves, and sample collection and transport. Inappropriate physical and chemical growth conditions in the laboratory for the isolation and cultivation of cave microorganisms pose many complications including length of cultivation; some cave microorganisms can take weeks and even months to grow. Additionally, DNA extraction from cave environmental samples may be difficult due to the high concentration of various minerals that are natural DNA blocking agents. Once cave microorganisms are grown in the lab, other problems often arise, such as maintenance of pure culture, consistency of antimicrobial activity and fermentation conditions for antimicrobial production. In this review, we suggest that, although based on what has been done in the field, there is potential in using cave microorganisms to produce antimicrobial agents, one needs to be highly committed and prepared.

Journal Article
Journal Article

Analysis of chemical signatures of alkaliphiles using fatty acid methyl ester analysis

Authors: Sreenivasulu, B; Paramageetham, C; Sreenivasulu, D; Suman, B; Umamahesh, K; Babu, GP (2017) 9:106-114. HERO ID: 3859569

[Less] BACKGROUND: Fatty acids occur in nearly all living organisms as the important predominant . . . [More] BACKGROUND: Fatty acids occur in nearly all living organisms as the important predominant constituents of lipids. While all fatty acids have essentially the same chemical nature, they are an extremely diverse group of compounds.

MATERIALS AND METHODS: To test the hypothesis, fatty acids of alkaliphiles isolates, Bacillus subtilis SVUNM4, Bacillus licheniformis SVUNM8, Bacillus methylotrohicus SVUNM9, and Paenibacillus dendritiformis SVUNM11, were characterized compared using gas chromatography-mass spectrometry (GC-MS) analysis.

RESULTS: The content of investigated ten fatty acids, 1, 2-benzenedicarboxylic acid butyl 2-methylpropyl ester, phthalic acid, isobutyl 2-pentyl ester, dibutyl phthalate, cyclotrisiloxane, hexamethyl, cyclotetrasiloxane, octamethyl, dodecamethyl, heptasiloxane 1,1,3,3,5,5,7,7,9,9,11,11,13,13-etradecamethyl, 7,15-dihydroxydehydroabietic acid, methyl ester, di (trimethylsilyl) ether, hentriacontane, 2-thiopheneacetic acid, undec-2-enyl ester, obviously varied among four species, suggesting each species has its own fatty acid pattern.

CONCLUSIONS: These findings demonstrated that GC-MS-based fatty acid profiling analysis provides the reliable platform to classify these four species, which is helpful for ensuring their biotechnological interest and novel chemotaxonomic.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Urinary phthalate and phthalate alternative metabolites and isoprostane among couples undergoing fertility treatment

Authors: Wu, H; Olmsted, A; Cantonwine, DE; Shahsavari, S; Rahil, T; Sites, C; Pilsner, JR (2017) Environmental Research 153:1-7. HERO ID: 3483281

[Less] BACKGROUND: Epidemiological data suggest associations between phthalate exposures to . . . [More] BACKGROUND: Epidemiological data suggest associations between phthalate exposures to a variety of adverse reproductive outcomes including reduced sperm quality and reproductive success. While mechanisms of these associations are not fully elucidated, oxidative stress has been implicated as a potential mediator. We examined associations of urinary metabolites of phthalates and phthalate alternative plasticizers with oxidative stress among couples seeking fertility treatment.

METHODS: Seventeen urinary plasticizer metabolites and 15-F2t isoprostane, a biomarker of oxidative stress, were quantified in spot samples from 50 couples seeking fertility treatment who enrolled in the Sperm Environmental Epigenetics and Development Study during 2014-2015.

RESULTS: In multivariable analyses, percent change in isoprostane was positively associated with interquartile range increases for the oxidative metabolites of di-2-ethylhexyl phthalate, [mono-2-ethyl-5-hydroxyhexyl phthalate (MEHHP; 20.0%, p=0.02), mono-2-ethyl-5-oxohexyl phthalate (MEOHP; 24.1%, p=0.01), and mono-2-ethyl-5-carboxypentyl phthalate (MECPP; 24.1%, p=0.004)], mono-isobutyl phthalate (MiBP; 17.8%, p=0.02), mono-hydroxyisobutyl phthalate (MHiBP; 27.5%, p=0.003), and cyclohexane-1,2-dicarboxylic acid mono-hydroxy-isononyl ester (MHINCH; 32.3%, p=0.002). Stratification of participants by sex revealed that isoprostane was positively associated with MHiBP (41.4%, p=0.01) and monocarboxy-isononyl phthalate (MCNP; 26.0%, p=0.02) among females and MEOHP (35.8%, p=0.03), MiBP (29.2%, p=0.01), MHiBP (34.7%, p=0.007) and MHINCH (49.0%, p=0.002) among males.

CONCLUSIONS: Our results suggest that exposure to phthalates and phthalate replacements are associated with higher levels of oxidative stress in a sex-specific manner. Additional studies are needed to replicate our findings and to examine the potential health implications of the use of phthalates and alternative phthalates in consumer end products.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Effects of gender on the association of urinary phthalate metabolites with thyroid hormones in children: a prospective cohort study in Taiwan

Authors: Weng, TI; Chen, MH; Lien, GW; Chen, PS; Lin, JC; Fang, CC; Chen, PC (2017) International Journal of Environmental Research and Public Health 14:123. HERO ID: 3515112

[Less] Phthalates are considered endocrine disruptors. Our study assessed the gender-specific effects of phthalate . . . [More] Phthalates are considered endocrine disruptors. Our study assessed the gender-specific effects of phthalate exposure on thyroid function in children. In total, 189 Taiwanese children were enrolled in the study. One-spot urine and blood samples were collected for analyzing 12 phthalate metabolites in urine and thyroid hormones. The association between urinary phthalate metabolites and serum thyroid hormones was determined using a generalized linear model with a log link function; the children were categorized into groups for analysis according to the 33rd and 66th percentiles. The data were stratified according to gender and adjusted for a priori defined covariates. In girls, a positive association existed between urinary di-2-ethylhexyl phthalate (DEHP) metabolites (mono-(2-ethylhexyl) phthalate, mono-(2-ethyl-5-oxohexyl) phthalate, and mono-(2-ethyl-5-hydroxyhexyl) phthalate) and free thyroxine (T4). In boys, urinary dibutyl phthalate (DBP) metabolites (mono-i-butyl phthalate and mono-n-butyl phthalate) were positively associated with free triiodothyronine (T3). After categorizing each exposure into three groups, urinary DEHP metabolites were positively associated with free T3 levels in boys. Our results suggested that DEHP is associated with free T4 in girls and that DBP is associated with free T3 in boys. Higher DEHP metabolite concentrations exerted larger effects on free T3 in boys. These results reveal the gender-specific relationships between phthalate metabolites and thyroid hormones.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Occurrence, removal and health risk assessment of phthalate esters in the process streams of two different wastewater treatment plants in Lagos and Ogun States, Nigeria

Authors: Olujimi, OO; Aroyeun, OA; Akinhanmi, TF; Arowolo, TA (2017) Environmental Monitoring and Assessment 189:345. HERO ID: 3859033

[Less] Phthalate esters (PEs) are one of the environmentally active organic pollutants capable of causing endocrine . . . [More] Phthalate esters (PEs) are one of the environmentally active organic pollutants capable of causing endocrine disruption. The levels of PE congeners were determined in the influent and effluent from Covenant Oxidation Pond (COP) and Ikeja Wastewater Treatment Plant (IWWTP). Standard methods were adopted for determining the physical and chemical parameters of the water samples. The water samples for PE congener's determination were collected, acidified and stored at 4 °C prior to liquid-liquid extraction and analysis by gas chromatograph. The possible health risk associated with the usage of effluent-polluted river water was also investigated. The pH and temperature ranges were within the Federal Ministry of Environment (FME) 2001 guideline limits while the dissolved oxygen, biochemical oxygen demand and chemical oxygen demand were above the limits. The IWWTP performed better at removing PEs at 54% compared to 43.3% on average at COP. The health risk of individual PE congener showed no non-cancer effects (HQ) as the values varied from 5.01E-05 (DAP) to 1.52E-02 (DEHP) for adults and 1.17E-04 (DAP) to 3.76E-03 (DBP) for children at COP, while at IWWTP, it ranged from 8.06E-05 (DIBP) to 1.09E-02 (DEHP) for adults and 5.68E-04 (MMP) to 2.54E-02 (DEHP) for children. Notwithstanding, the usage of effluent-polluted river water by local communities downstream may result in carcinogenic effects due to the cumulative effects of the PE congeners as the values obtained for adults and children for the ingestion and dermal routes for the two waste process streams ranged from 4.67E-06 (IWWTP) to 6.22E-05 (IWWTP) and 2.18E-05 (IWWTP) to 7.18E-05 (COP), respectively.