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The 3T3-L1 preadipocyte culture system has been used to examine numerous compounds that influence adipocyte differentiation or function. The perfluoroalkyl acids (PFAAs), used as surfactants in a variety of industrial applications, are of concern as environmental contaminants that are detected worldwide in human serum and animal tissues. This study was designed to evaluate the potential for PFAAs to affect adipocyte differentiation and lipid accumulation using mouse 3T3-L1 cells. Cells were treated with perfluorooctanoic acid (PFOA) (5-100 µM), perfluorononanoic acid (PFNA) (5-100 µM), perfluorooctane sulfonate (PFOS) (50-300 µM), perfluorohexane sulfonate (PFHxS) (40-250 µM), the peroxisome proliferator activated receptor (PPAR) PPARα agonist Wyeth-14,643 (WY-14,643), and the PPARγ agonist rosiglitazone. The PPARγ agonist was included as a positive control as this pathway is critical to adipocyte differentiation. The PPARα agonist was included as the PFAA compounds are known activators of this pathway. Cells were assessed morphometrically and biochemically for number, size, and lipid content. RNA was extracted for qPCR analysis of 13 genes selected for their importance in adipocyte differentiation and lipid metabolism. There was a significant concentration-related increase in cell number and decreased cell size after exposure to PFOA, PFHxS, PFOS, and PFNA. All four PFAA treatments produced a concentration-related decrease in the calculated average area occupied by lipid per cell. However, total triglyceride levels per well increased with a concentration-related trend for all compounds, likely due to the increased cell number. Expression of mRNA for the selected genes was affected by all exposures and the specific impacts depended on the particular compound and concentration. Acox1 and Gapdh were upregulated by all six compounds. The strongest overall effect was a nearly 10-fold induction of Scd1 by PFHxS. The sulfonated PFAAs produced numerous, strong changes in gene expression similar to the effects after treatment with the PPARγ agonist rosiglitazone. By comparison, the effects on gene expression were muted for the carboxylated PFAAs and for the PPARα agonist WY-14,643. In summary, all perfluorinated compounds increased cell number, decreased cell size, increased total triglyceride, and altered expression of genes associated with adipocyte differentiation and lipid metabolism., (Published by Elsevier Ireland Ltd.)

The hypothalamic supraoptic nucleus (SON) and paraventricular nucleus (PVN) consists of two types of magnocellular neurosecretory cells, oxytocin (OXT) and arginine vasopressin (AVP). We generated and characterized rats that express an OXT-monomeric red fluorescent protein 1 (mRFP1) and an AVP-enhanced green fluorescent protein (eGFP) fusion transgene. These transgenic rats enable the visualization of OXT or AVP neurons. Taking advantage of this, we examined the differences between OXT-mRFP1 neurons and AVP-eGFP neurons in response to acid. Acid-sensing ion channels (ASICs) are neuronal voltage-insensitive cationic channels that are activated by extracellular acidification. Although functional ASICs have been identified in AVP neurons, differences in acid-induced currents between OXT and AVP neurons in SON have not been reported. In the present study, we used the whole-cell patch-clamp technique to investigate differences between OXT-mRFP1 neurons and AVP-eGFP neurons reaction to acid in SON and PVN. In voltage clamp mode, lowering extracellular pH evoked inward currents in both OXT-mRFP1 neurons and AVP-eGFP neurons. In our findings, the acid-induced currents in the OXT-mRFP1 neurons were significantly smaller than those in the AVP-eGFP neurons. These acid-induced currents were inhibited by amiloride, a known blocker of ASICs. Further, to compare the response to acid between OXT-mRFP1 and AVP-eGFP neurons in the same transgenic rat, we used a double transgenic rat by mating an OXT-mRFP1 transgenic rat with an AVP-eGFP transgenic rat. The acid-induced currents of OXT-mRFP1 neurons were significantly smaller than those of AVP-eGFP neurons from the double transgenic rats. These currents were almost completely inhibited by amiloride. The difference of acid-sensitivity between OXT and AVP neurons might contribute to maintaining systematic order in hypothalamic function., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

In this study, we isolated a new sulfonic acid derivative, (Z)-4-methylundeca-1,9-diene-6-sulfonic acid (1), from the sea urchin collected from the Sea of Okhotsk. We established the structure of this new compound by analysis of NMR and HRMS data, along with comparison of the data with those of the related compounds reported in the literature. In addition, we investigated its anti-inflammatory effects in LPS-stimulated RAW264.7 macrophages. Compound 1 inhibited the production of NO, iNOS, PGE2, and COX-2, and it also suppressed the production of pro-inflammatory cytokines, such as TNF-α and IL-1β. It inhibited the translocation of the NF-κB subunit p65 into the nucleus by interrupting the phosphorylation and degradation of IκB-α. In addition, compound 1 significantly decreased the phosphorylation of JNK and p38 in LPS-stimulated RAW264.7 macrophages, suggesting that suppression of the inflammation process by compound 1 was mediated through the MAPK pathway. Taken together, this study showed that the anti-inflammatory effects of a new sulfonic acid derivative, (Z)-4-methylundeca-1,9-diene-6-sulfonic acid were mediated through the inhibition of NF-κB and JNK/p38 MAPK signaling pathways.

Studies on the origin of animal multicellularity have increasingly focused on one of the closest living relatives of animals, the choanoflagellate Salpingoeca rosetta. Single cells of S. rosetta can develop into multicellular rosette-shaped colonies through a process of incomplete cytokinesis. Unexpectedly, the initiation of rosette development requires bacterially produced small molecules. Previously, our laboratories reported the planar structure and femtomolar rosette-inducing activity of one rosette-inducing small molecule, dubbed rosette-inducing factor 1 (RIF-1), produced by the Gram-negative Bacteroidetes bacterium Algoriphagus machipongonensis. RIF-1 belongs to the small and poorly explored class of sulfonolipids. Here, we report a modular total synthesis of RIF-1 stereoisomers and structural analogs. Rosette-induction assays using synthetic RIF-1 stereoisomers and naturally occurring analogs defined the absolute stereochemistry of RIF-1 and revealed a remarkably restrictive set of structural requirements for inducing rosette development.

We previously demonstrated that the nonionic surfactants, nonylphenol polyethoxylates (NPEOs) induced the phosphorylation of histone H2AX (γ-H2AX), accompanied by DNA double-strand breaks (DSBs), and that exposure to ultraviolet (UV) degraded NPEOs, which sometimes enhanced their DNA-damaging ability. In this study, we showed that linear alkylbenzene sulfonates (LAS), general anion surfactants, also generated DSBs with γ-H2AX, and this ability was attenuated by UVB exposure. In the human breast adenocarcinoma cell line, MCF-7, γ-H2AX was generated in a dose-dependent manner immediately after cells were treated with LAS, and this was attributed to the formation of DSBs and was independent of cell cycle phases. The ability to generate γ-H2AX was markedly reduced in LAS exposed to UVB. HPLC analysis revealed that LAS were a mixture of various alkyl chain lengths, the peaks of which were detected at individual retention times. UVB evenly decreased all peaks of LAS, without migration of peaks to other retention times, which indicated that UVB may degrade the benzene ring of LAS, but did not shorten the alkyl chains. UVB is an important environmental factor in the degradation of LAS exhibiting the ability to induce DSBs, the most serious type of DNA damage., (© 2014 The American Society of Photobiology.)

Specific inhibitors such as 2-bromoethanesulfonate (BES) and vancomycin were employed in activity batch tests to decipher metabolic pathways that are preferentially used by a mixed anaerobic consortium (sludge from an anaerobic digester) to transform carbon monoxide (CO) into methane (CH4). We first evaluated the inhibitory effect of both BES and vancomycin on the microbial community, as well as the efficiency and stability of vancomycin at 35 °C, over time. The activity tests with CO2-H2, CO, glucose, acetate, formate, propionate, butyrate, methanol, and ethanol showed that vancomycin does not inhibit some Gram-negative bacteria, and 50 mmol/L BES effectively blocks CH4 production in the sludge. However, when sludge was incubated with propionate, butyrate, methanol, or ethanol as the sole energy and carbon source, methanogenesis was only partially inhibited by BES. Separate tests showed that 0.07 mmol/L vancomycin is enough to maintain its inhibitory efficiency and stability in the population for at least 32 days at 35 °C. Using the inhibitors above, it was demonstrated that CO conversion to CH4 is an indirect, 2-step process, in which the CO is converted first to acetate and subsequently to CH4.

Delivery of therapeutic macromolecules is limited by the physiological limitations of the gastrointestinal tract including poor intestinal permeability, low pH and enzymatic activity. Several permeation enhancers have been proposed to enhance intestinal permeability of macromolecules; however their utility is often hindered by toxicity and limited potency. Here, we report on a novel permeation enhancer, Dimethyl palmitoyl ammonio propanesulfonate (PPS), with excellent enhancement potential and minimal toxicity. PPS was tested for dose- and time-dependent cytotoxicity, delivery of two model fluorescent molecules, sulforhodamine-B and FITC-insulin in vitro, and absorption enhancement of salmon calcitonin (sCT) in vivo. Caco-2 studies revealed that PPS is an effective enhancer of macromolecular transport while being minimally toxic. TEER measurements in Caco-2 monolayers confirmed the reversibility of the effect of PPS. Confocal microscopy studies revealed that molecules permeate via both paracellular and transcellular pathways in the presence of PPS. In vivo studies in rats showed that PPS enhanced relative bioavailability of sCT by 45-fold after intestinal administration. Histological studies showed that PPS does not induce damage to the intestine. PPS is an excellent permeation enhancer which provides new opportunities for developing efficacious oral/intestinal delivery systems for therapeutic macromolecules., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Perfluorooctane sulfonate (PFOS) poses potential risks to reproduction and development. Mouse embryonic stem cells (mESCs) are ideal models for developmental toxicity testing of environmental contaminants in vitro. However, the mechanism by which PFOS affects early embryonic development is still unclear. In this study, mESCs were exposed to PFOS for 24 h, and then general cytotoxicity and pluripotency were evaluated. MTT assay showed that neither PFOS (0.2 µM, 2 µM, 20 µM, and 200 µM) nor control medium (0.1% DMSO) treatments affected cell viability. Furthermore, there were no significant differences in cell cycle and apoptosis between the PFOS treatment and control groups. However, we found that the mRNA and protein levels of pluripotency markers (Sox2, Nanog) in mESCs were significantly decreased following exposure to PFOS for 24 h, while there were no significant changes in the mRNA and protein levels of Oct4. Accordingly, the expression levels of miR-145 and miR-490-3p, which can regulate Sox2 and Nanog expressions were significantly increased. Chrm2, the host gene of miR-490-3p, was positively associated with miR-490-3p expression after PFOS exposure. Dual luciferase reporter assay suggests that miR-490-3p directly targets Nanog. These results suggest that PFOS can disturb the expression of pluripotency factors in mESCs, while miR-145 and miR-490-3p play key roles in modulating this effect.

To date, little work has been conducted on the relationship between solute and buffer molecules and conformational exchange motion in enzymes. This study uses solution NMR to examine the effects of phosphate, sulfate, and acetate in comparison to MES- and HEPES-buffered references on the chemical shift perturbation and millisecond, chemical, or conformational exchange motions in the enzyme ribonuclease A (RNase A), triosephosphate isomerase (TIM) and HisF. The results indicate that addition of these solutes has a small effect on (1)H and (15)N chemical shifts for RNase A and TIM but a significant effect for HisF. For RNase A and TIM, Carr-Purcell-Meiboom-Gill relaxation dispersion experiments, however, show significant solute-dependent changes in conformational exchange motions. Some residues show loss of millisecond motions relative to the reference sample upon addition of solute, whereas others experience an enhancement. Comparison of exchange parameters obtained from fits of dispersion data indicates changes in either or both equilibrium populations and chemical shifts between conformations. Furthermore, the exchange kinetics are altered in many cases. The results demonstrate that common solute molecules can alter observed enzyme millisecond motions and play a more active role than what is routinely believed.

To use the selective inhibition method for quantitative analysis of acetate metabolism in methanogenic systems, the responses of microbial communities and metabolic activities, which were involved in anaerobic degradation of acetate, to the addition of methyl fluoride (CH3F), 2-bromoethanesulfonate (BES) and hydrogen were investigated in a thermophilic batch experiment. Both the methanogenic inhibitors, i.e., CH3F and BES, showed their effectiveness on inhibiting CH4 production, whereas acetate metabolism other than acetoclastic methanogenesis was stimulated by BES, as reflected by the fluctuated acetate concentration. Syntrophic acetate oxidation was thermodynamically blocked by hydrogen (H2), while H2-utilizing reactions as hydrogenotrophic methanogenesis and homoacetogenesis were correspondingly promoted. Results of PCR-DGGE fingerprinting showed that, CH3F did not influence the microbial populations significantly. However, the BES and hydrogen notably altered the bacterial community structures and increased the diversity. BES gradually changed the methanogenic community structure by affecting the existence of different populations to different levels, whilst H2 greatly changed the abundance of different methanogenic populations, and induced growth of new species.

To study the behavior of perfluoroalkyl substances (PFASs) in soil and the carry-over from soil to plants, technical mixtures of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) at a concentration of 25 mg/kg soil were applied to 1.5 m(3) monolithic soil columns of a lysimeter. Growth samples and percolated water were analyzed for PFASs throughout a period of 5 years. In addition to PFOA/PFOS plant compartments and leachate were found to be contaminated with short-chain PFASs. Calculation showed significant decreasing trends (p < 0.05) for all substances tested in the growth samples. Short-chain PFASs and PFOA pass through the soil much more quickly than PFOS. Of the 360 g of PFOA and 367.5 g of PFOS applied to the soil, 96.88% PFOA and 99.98% PFOS were still present in the soil plot of the lysimeter after a period of 5 years. Plants accumulated 0.001% PFOA and 0.004% PFOS. Loss from the soil plot through leachate amounted to 3.12% for PFOA and 0.013% for PFOS.

In this work we show how a new promising green and highly water-soluble surfactant can be designed based on recent progress in the knowledge of counterion-headgroup binding and crystallization behavior. The result is the combination of a most classical surfactant anion, dodecylsulfate (DS), with choline (Ch), a natural green cation. The advantage of the physiological metabolite choline is its bulky structure that prevents ChDS from easy crystallization and thus leads to a considerable lowering of the Krafft point down to 0°C. The counterion-headgroup binding is reflected by the aqueous phase behavior of ChDS. Conductivity, surface tension, and cryo-TEM measurements allow the characterization of the dilute micellar region, while the penetration scan technique enables the establishment of a preliminary aqueous phase diagram. In addition, the influence of different mono- and divalent salts on the solubility of ChDS is investigated. The results are compared to the alkali sulfate and alkylcarboxylate homologs, and reveal that ChDS is less sensitive towards addition of salts than, for instance, choline carboxylates due to an increased counterion-headgroup association. Further, cytotoxicity tests on HeLa and SK-Mel 28 cells are presented and compared to other surfactants, showing that ChDS is no more harmful than its sodium counterpart SDS. Taken together, our findings highlight that the harmless green cation choline is of great potential for the design of new surfactants., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Two soil-free anaerobic dechlorinating cultures (3-CP and 35-DCP) were enriched from a pentachlorophenol (PCP)-to-phenol dechlorinating soil-dependent culture, using 3-chlorophenol (3-CP) and 3,5-dichlorophenol (3,5-DCP) as specific respective substrates, and characterized polyphasically. Physiological characterization indicated that the 3-CP and 35-DCP cultures had similar features, but with some variations. Both cultures utilized formate or acetate preferably as optimum electron donors for reductive dechlorination, and they shared similar patterns of dechlorination spectra for chlorophenols ranging from mono-CPs to a tetra-CP, with preferred dechlorination pathways in the ortho and meta positions. Alternative electron acceptors such as NO(3)(-) but not SO(4)(2-) inhibited the dechlorination activity in both cultures, while amorphous iron oxides (FeOOH) suppressed dechlorination activity only in the 35-DCP culture. Complete inhibition of dechlorination was observed in both cultures supplemented with chloramphenicol and vancomycin. The addition of 2-bromoethanesulfonate resulted in delayed dechlorination activity in the 35-DCP culture but not in the 3-CP culture; molybdate did not exert any inhibitory effect in either culture. Phylogenetic analysis based on 16S rRNA genes confirmed that the two cultures exhibited similar bacterial species but with varied responsible dechlorinators. Dehalobacter spp. were the likely dechlorinators in the 3-CP culture versus Sulfurospirillum spp. in the 35-DCP culture, with Clostridium and Clostridium-like spp. as candidate dechlorinators in both cultures., (Copyright © 2012 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Background: Perfluorinated chemicals (PFCs) have been widely used and have emerged as important food contaminants. A recent study on pregnant women suggested that PFC exposure was associated with a longer time to pregnancy (TTP). We examined the association between serum concentrations of PFCs in females and TTP in 222 Danish first-time pregnancy planners during the years 1992-1995., Methods: The couples were enrolled in the study when discontinuing birth control and followed for six menstrual cycles or until a clinically recognized pregnancy occurred. Fecundability ratio (FR) was calculated using discrete-time survival models. In addition, odds ratio (OR) for TTP >6 cycles was calculated., Results: OR for TTP >6 cycles for those with PFC concentrations above the median were 0.96 [95% confidence interval (CI): 0.54-1.64] for perfluorooctane sulfonic acid (PFOS), the major PFC, compared with those below the median. FRs for those with PFOS concentrations above the median were 1.05 (95% CI: 0.74-1.48) compared with those below the median. Other PFCs showed the same lack of association with TTP. The results were not affected by adjustment for covariates. PFOS and perfluorooctanoic acid concentrations were similar to those observed in a previous Danish study., Conclusions: These findings suggest that exposure to PFCs affects TTP only to a small extent, if at all.

Perfluoroalkyl substances (PFASs) are man-made polyfluorinated compounds that are widely used and persistent in the environment. PFASs have potential effects on many biological systems including the development of lung. Glucocorticoids have been reported to promote fetal and neonatal lung development at the late stage, and 11β-hydroxysteroid dehydrogenase 1(11βHSD1) in the lung is critical for the generation of local active glucocorticoid cortisol (human) or corticosterone (rodents) from biologically inert 11keto-steroids. The purpose of the present study is to study the direct inhibitory effects of PFASs on 11βHSD1 activities and action modes. Microsomal 11βHSD1 was subjected to the exposure to various PFASs, including perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), potassium perfluorohexanesulfonate (PFHxS) and potassium perfluorobutane sulfonate (PFBS). PFOS and PFOA inhibited neonatal rat lung 11βHSD1 activity with IC(50)s of 3.45μM (95% Confidence Intervals, CI(95): 1.97-6.37μM) and 45.31μM (CI(95): 27.64-74.26μM), respectively, while PFHxS and PFBS did not inhibit the enzyme activity at 250μM. PFOS and PFOA inhibited human 11βHSD1 activity with IC(50)s of 7.56μM (CI(95): 2.86-19.97μM) and 37.61μM (CI(95): 24.49-57.75μM), respectively, while PFHxS and PFBS did not inhibit the enzyme activity at 250μM. PFASs showed competitive inhibition on both human and rat 11βHSD1. In conclusion, the present study shows that PFOS and PFOA are the inhibitors of 11βHSD1., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

An L(16) (4(5)) orthogonal experimental design was used to evaluate combination effects of nitroethane (0-15 mM), 2-nitroethanol (0-15 mM), 2-nitro-1-propanol (0-15 mM), pyromellitic diimide (0-0.07 mM), and 2-bromoethanesulfonate (0-0.05 mM) on in vitro ruminal fermentation of a grain-rich feed. In vitro dry matter disappearance was adversely affected by these inhibitors, while cumulative gas production was not affected. Volatile fatty acid production was increased by nitroethane and 2-bromoethanesulfonate in a dose-dependent manner and was decreased by 2-nitroethanol and pyromellitic diimide. All inhibitor treatments increased the molar acetate proportion, while decreasing proportions of propionate and butyrate; hydrogen recovery was decreased by 36.9-45.2%; and methane production was reduced by 95.2-99.2%. The methanogenesis inhibition ranked: nitroethane > 2-nitroethanol > 2-nitro-1-propanol > 2-bromoethanesulfonate > pyromellitic diimide; combined concentrations of 5, 5, 5, 0.02, and 0.03 mM, respectively, gave the optimal inhibiting efficiency. These results may provide a reference to develop effective mitigation of methane emission from ruminants.

Perfluorooctane sulfonate (PFOS) is a chemically stable compound extensively used as oil and water repellent, surface active agents in our daily life. Accumulative research evidence gradually appears the toxicity of PFOS against mammals, but the whole figure remains to be elucidated. The present study was conducted to know the effects of PFOS on human hepatic drug metabolizing-type cytochrome P450 (CYP) isoenzymes such as CYP1A2 (7-ethoxyresorufin as a substrate), CYP2A6 (coumarin), CYP2B6 (7-ethoxy-4-trifluoromethylcoumarin), CYP2C8 (paclitaxel), CYP2C9 (diclofenac), CYP2C19 (S-mephenytoin), CYP2D6 (bufuralol), CYP2E1 (chlorzoxazone) and CYP3A4 (testosterone) in human livers employing their typical substrates. Although all of the oxidation reactions tested were more or less inhibited by PFOS, diclofenac 4'-hydroxylation mediated mainly by CYP2C9 was most strongly inhibited (K(i) value of 40 nM), followed by paclitaxel 6α-hydroxylation mediated mainly by CYP2C8 (K(i) value of 4 μM). The substrate oxidation reactions catalyzed by CYP2A6, CYP2B6, CYP2C19 and CYP3A4 were moderately (K(i) values of 35 to 45 μM), and those by CYP1A2, CYP2D6 and CYP2E1 were weakly inhibited by PFOS (K(i) values of 190-300 μM). The inhibition by PFOS for coumarin 7-hydroxylation mainly catalyzed by human liver microsomal CYP2A6 as well as by the recombinant enzyme was found to be enhanced by the preincubation of PFOS with human liver microsomes and NADPH as compared to the case without preincubation. The inhibition of the human liver microsomal cumarin 7-hydroxylation was PFOS concentration-dependent, and exhibited pseudo-first-order kinetics with respect to preincubation time, yielding K(inact) and K(I) values of 0.06 min(-1) and 23 μM, respectively. These results suggest that the metabolism of medicines which are substrates for CYP2C9 may be altered by PFOS in human bodies, and that PFOS is a mechanism-based inhibitor of CYP2A6., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Mercury methylation and demethylation rates were measured in periphyton biofilms growing on submerged plants from a shallow fluvial lake located along the St. Lawrence River (Quebec, Canada). Incubations were performed in situ within macrophytes beds using low-level spikes of (199)HgO and Me(200)Hg stable isotopes as tracers. To determine which microbial guilds are playing a role in these processes, methylation/demethylation experiments were performed in the absence and presence of different metabolic inhibitors: chloramphenicol (general bacteriostatic inhibitor), molybdate (sodium molybdate, a sulfate reduction inhibitor), BESA (2-bromoethane sulfonic acid, a methanogenesis inhibitor), and DCMU (3-(3,4-dichlorophenyl)-1,1 dimethyl urea, a photosynthesis inhibitor). Active microbes of the periphytic consortium were also characterized using 16S rRNA gene sequencing. Methylation rates in the absence of inhibitors varied from 0.0015 to 0.0180 d(-1) while demethylation rates ranged from 0.083 to 0.217 d(-1), which corresponds to a net methylmercury balance of -0.51 to 1.28 ng gDW periphyton(-1) d(-1). Methylation rates were significantly decreased by half by DCMU and chloramphenicol, totally inhibited by BESA, and were highly stimulated by molybdate. This suggests that methanogens rather than sulfate reducing bacteria were likely the primary methylators in the periphyton of a temperate fluvial lake, a conclusion supported by the detection of 16S rRNA gene sequences that were closely related to those of methanogens. This first clear demonstration of methanogens' role in mercury methylation in environmental periphyton samples expands the known diversity of microbial guilds that contribute to the formation of the neurotoxic substance methylmercury.

Novel biodegradable polycaprolactone containing N,N'-bis (2-hydroxyethyl) methylamine ammonium propane sulfonate (PCL-APS) was synthesized by ring-opening polymerization. The resulting polymers were characterized by nuclear magnetic resonance spectrum (NMR), Fourier transform infrared (FTIR) spectroscopy, gel permeation chromatograph (GPC), differential scanning calorimetry (DSC), and water contact angle (WCA). These measurements showed that the APS unit was introduced into polymers. The hydrolysis of PCL-APS was evaluated by soaking the polymer membranes in a pH = 3.20 acid solution. The rate of weight loss was increased with the content of APS increasing in polymer. The compatibility of polymers were evaluated by platelet adhesion, hemolytic test, and activated partial thromboplastic time (APTT) and prothrombin time (PT) experiments. Results showed that adhered platelets deceased after introducing sulfobetaine as compared to the control PCL, little hemolysis took place on PCL-APS, and APTT of PCL-APS polymers was prolonged than that of control PCL. Therefore, polycaprolactone containing sulfobetaine is a promising biodegradable polymer with good blood compatibility., (Copyright © 2011 Wiley Periodicals, Inc.)

Objective: To investigate the effect of linear alkylbenzenesulfonate (LAS) on the reproductive capacity and life-span of Drosophila melanogaster., Methods: Drosophila melanogaster images within 8 h after eclosion were collected with ether anesthesia. The female and male of similar size and normal shape and behavior were selected. The Drosophila melanogasters were cultured in the culture medium containing LAS of different densities. We divided the Drosophila melanogaster into 4 groups according to LAS concentrations: a low dose group with LAS 150 mg/kg, a middle dose group with LAS 300 mg/kg,a high dose group with LAS 600 mg/kg, and a control group without LAS, respectively. The changes of the reproductive capacity, median lethal time, mean life-span and max mean life-span of drosophila melanogaster with different doses of LAS were measured and compared with those of the control., Results: The pupa numbers of filial generation of Drosophila melanogaster in the low, middle, and high dose groups (85.07%, 84.59% and 71.88%, respectively) were lower than those in the control group (P<0.01). The median lethal time, mean life-span and max mean life-span of Drosophila melanogaster in the low, middle, and high dose groups were shorter than those in the control group (P<0.05). The change of life-span of Drosophila melanogaster in the high dose group was remarkable: the median lethal time of female and male shortened 13 days and 15 days, the mean life-span of female and male shortened 18 days and 14 days, and the max mean life-span of female and male shortened 14 days and 12 days, respectively., Conclusion: LAS has definite toxicity to Drosophila melanogaster, which can degrade the reproductive capacity of Drosophila melanogaster and shorten the life-span of Drosophila melanogaster.

Benzothiazole is a common scaffold on which many bioactive structures, including protein inhibitors and biosensors, are based. The potential self-aggregation of such molecules to form nanoparticles is relevant for a number of practical applications. 3-(2-Benzothiazolylthio)-propanesulfonic acid (BTS) has been reported as a powerful and selective inhibitor of triosephosphate isomerase from Trypanosoma cruzi, the parasite that causes the Chagas' disease. Electrical conductivity, sound velocity, density, and nuclear magnetic resonance experiments as a function of temperature and of NaCl concentration have been performed in the present work to provide a comprehensive physicochemical description of this compound in aqueous solution. Molecular dynamics simulations of the same system were also performed to characterize the structure and dynamic behavior of the corresponding aggregates at several concentrations of BTS.

The sulfonolipid, sulfobacin B, is isolated from Chryseobacterium sp. and functions both as a von Willebrand factor receptor antagonist and a DNA polymerase (pol) α inhibitor. Previously, we chemically synthesized sulfobacin B by starting from L-cysteine. In this study, we investigated the inhibitory effects of chemically synthesized sulfobacin B on the activity of pols and other DNA metabolic enzymes. Sulfobacin B selectively inhibited the activity of all animal pol species: Among the pols tested, the inhibitory effect of the compound on pol λ activity was the strongest with IC50 values of 1.6 µM. However, sulfobacin B did not influence the activity of plant or prokaryotic pols, or that of the other DNA metabolic enzymes such as primase of pol α, RNA polymerase, polynucleotide kinase or deoxyribonuclease I. As we previously found a positive relationship between pol λ inhibition and anti-inflammation, we examined whether sulfobacin B could inhibit inflammatory responses. The compound caused a marked reduction in 12-O-tetradecanoylphorbol-13-acetate-induced acute inflammation in the mouse ear. In a cell culture system using mouse macrophages, sulfobacin B strongly inhibited the production of tumor necrosis factor (TNF)-α and the action of nuclear factor-κB induced by lipopolysaccharide (LPS). In an in vivo mouse model of LPS-induced acute inflammation, the intraperitoneal injection of sulfobacin B to mice led to the suppression of serum TNF-α production. These results indicate that sulfobacin B is a potential chemotherapeutic agent for inflammation.

The bacterial metabolism of epoxypropane formed from propylene oxidation uses the atypical cofactor coenzyme M (CoM, 2-mercaptoethanesulfonate) as the nucleophile for epoxide ring opening and as a carrier of intermediates that undergo dehydrogenation, reductive cleavage, and carboxylation to form acetoacetate in a three-step metabolic pathway. 2-Ketopropyl-CoM carboxylase/oxidoreductase (2-KPCC), the terminal enzyme of this pathway, is the only known member of the disulfide oxidoreductase family of enzymes that is a carboxylase. In the present work, the CoM analog 2-bromoethanesulfonate (BES) is shown to be a reversible inhibitor of 2-KPCC and hydroxypropyl-CoM dehydrogenase but not of epoxyalkane:CoM transferase. Further investigations revealed that BES is a time-dependent inactivator of dithiothreitol-reduced 2-KPCC, where the redox active cysteines are in the free thiol forms. BES did not inactivate air-oxidized 2-KPCC, where the redox active cysteine pair is in the disulfide form. The inactivation of 2-KPCC exhibited saturation kinetics, and CoM slowed the rate of inactivation. Mass spectral analysis demonstrated that BES inactivation of reduced 2-KPCC occurs with covalent modification of the interchange thiol (Cys(82)) by a group with a molecular mass identical to that of ethylsulfonate. The flavin thiol Cys(87) was not alkylated by BES under reducing conditions, and no amino acid residues were modified by BES in the oxidized enzyme. The UV-visible spectrum of BES-modifed 2-KPCC showed the characteristic charge transfer absorbance expected with alkylation at Cys(82). These results identify BES as a reactive CoM analog that specifically alkylates the interchange thiol that facilitates thioether bond cleavage and enolacetone formation during catalysis.

The effects of two typical methanogenic inhibitors [2-bromoethanesulfonate (BES) and chloroform (CHCl(3))] on the bacterial populations were investigated using molecular ecological techniques. Terminal restriction fragment length polymorphism analyses (T-RFLP) in combination with clone library showed that both the toxicants not only inhibited methanogenic activity but also considerably altered the bacterial community structure. Species of low % G + C Gram-positive bacteria (Clostridiales), high % G + C Actinomycetes, and uncultured Chloroflexi showed relatively greater tolerance of CHCl(3), whereas the BES T-RFLP patterns were characterized by prevalence of Geobacter hydrogenophilus and homoacetogenic Moorella sp. In addition, due to indirect thermodynamic inhibition caused by high hydrogen partial pressures, the growth of obligately syntrophic acetogenic Syntrophomonas and Syntrophobacter was also affected by selective inhibition of methanogenesis. Interestingly, by comparing the fermentative intermediates detected in BES- and CHCl(3)-treated experiments, it was furthermore found that when methanogenesis is specifically inhibited, the syntrophic interaction between hydrogen-producing fatty acid degraders and hydrogen-utilizating homoacetogens seemed to be strengthened.

The adverse environmental exposure in early life may have adverse effects on animals through epigenetic aspects. The current study examined the possibility of early epigenetic alteration in PFOS-exposed rat liver. Pregnant Sprague-Dawley (SD) rats were exposed to perfluorooctane sulfonate (PFOS) at doses of 0.1, 0.6 and 2.0 mg/kg/d and 0.05% Tween 80 as control by gavage from gestation days 2 to 21. The dams were allowed to give birth and liver samples from weaned (postnatal day 21) offspring rats were analyzed for PFOS content, relative liver weight, global DNA methylation, methylation of LINE-1 regulatory region, tumor suppressor gene glutathione S-transferase pi (GSTP) and p16 promoter methylation level, as well as related genes expression level. In PFOS-exposed weaned rats, compared to the control, global DNA methylation and methylation of LINE-1 regulatory region decreased significantly only in the 2.0 mg/kg/d group. Up to 30% of critical CpG sites (+79, 81 and 84) in GSTP promoter region were methylated in the livers of PFOS-treated rats, while p16 promoter methylation was not affected. In addition, the up-regulated expression of GSTP was observed and this increase was associated with its main pathway of transcription regulation: Keap1-Nrf2/MafK. Thus, early-induced changes in critical cytosines within the GSTP gene promoter region may be a biomarker of hepatic PFOS burden, though their direct role in PFOS-induced hepatotoxicity, including its potential carcinogenic action, needs further research., (2010 Elsevier Ireland Ltd. All rights reserved.)

Occupational and environmental exposures to chemicals are major potential routes of exposure for direct skin toxicity and for systemic absorption. The majority of these exposures are to complex mixtures, yet most experimental studies to assess topical chemical absorption are conducted neat or in simple aqueous vehicles. A component of many industrial mixtures is surfactants that solubilize ingredients and stabilize mixtures of oily components when present in aqueous vehicles. The purpose of this series of experiments was to use two well-developed experimental techniques to assess how solution interactions present in a pure nonbiological in vitro system (membrane coated fibers, MCF) compare to those seen in a viable ex vivo biological preparation (isolated perfused porcine skin flap, IPPSF). Two widely encountered anionic surfactants, sodium lauryl sulfate (SLS) and linear alkylbenzene sulfonate (LAS), were studied in 10% solutions. The rank orders of absorption were: water: pentachlorophenol (PCP) > 4-nitrophenol (PNP) > parathion > fenthion > simazine > propazine; SLS: PNP > PCP > parathion > simazine > fenthion > propazine; and LAS: PNP > PCP > simazine > parathion > fenthion > propazine. For all penetrants, absorption was greater in SLS compared to LAS mixtures, a finding consistent with smaller micelle sizes seen with SLS. For these low-water-solubility compounds, absorption was greater from aqueous solutions in nearly every case. The inert three-fiber MCF array predicted absorptive fluxes seen in the ex vivo IPPSF, suggesting lack of any biological effects of the surfactants on skin.

Oral Bifidobacteriaceae, Bifidobacterium dentium and Bifidobacterium longum, are known to be isolated together with mutans streptococci and lactobacilli from caries lesions, suggesting that these Bifidobacteriaceae are caries associated and acid resistant. This study aimed to investigate effects of acidification on B. dentium and B. longum, and to compare them with those on Streptococcus mutans, Streptococcus sanguinis and Lactobacillus paracasei. Effects of acidification, growth ability in a complex medium at a pH of 4.0-8.0, cell viability in 2-morpholinoethanesulfonic acid monohydrate (MES)-KOH buffer at pH 4.0, as well as stability of intracellular pH (pH(in)) at an extracellular pH of 3.5-8.0 estimated using a fluorescent dye, 5(6)-carboxyfluorescein diacetate N-succinimidyl ester in MES-KOH, 3-(N-morpholino)propanesulfonic acid-KOH or N,N-bis(2-hydroxyethyl)glycine-KOH buffer, were investigated. B. longum grew as well as Streptococcus strains over a wide pH range, whereas B. dentium grew best in the narrow pH range around neutral. The cell viability of B. dentium decreased significantly after 2 h of acidification at a pH of 4.0, but this was significantly less than that of the Streptococcus and Lactobacillus species, whereas B. longum maintained almost 100% viability. The pH(in) was close to the extracellular pH at pH of 5.5-7.5 in the Bifidobacterium and Streptococcus strains, while at a pH of <5.0, the pH(in) was higher than the extracellular pH in all the strains, but the pH(in) maintenance ability of Bifidobacterium strains was higher than that of the Streptococcus strains. The high survival rate and pH(in) maintenance ability of bifidobacteria comparable to that of S. mutans in the acidic environment may account for why bifidobacteria exist as stable species in acidic caries lesions together with mutans streptococci., (Copyright © 2010 S. Karger AG, Basel.)

House dust mites (Dermatophagoides farinae) in bedding and clothes are a major allergen. However, house dust mites cannot be killed by general washing conditions under 50 degrees C. Therefore, low-temperature washing conditions must be improved to eliminate house dust mites. Sodium alkyl acyloxybenzene sulfonate (OBS) is a bleach activator that is used to intensify the bleaching effects of some laundry products. The purpose of this study was to evaluate the effect of OBS on the elimination of house dust mites in low-temperature washing conditions. D. farinae was soaked in solutions containing different types of OBS for various durations and at various temperatures. The miticidal effects of the various washing conditions were also evaluated for D. farinae. Then sodium lauroyloxybenzene sulfonate (OBS-12) produced the highest D. farinae mortality rate among the OBS solutions that were examined and had a stronger miticidal effect than available chlorine under general washing conditions. OBS exhibited miticidal effects under general washing conditions at low temperatures. Since OBS is already used as an additive in some laundry products to increase the bleaching activity, OBS can be easily used to kill house dust mites under general washing conditions.

Neurokinins (NK) released from terminals of dorsal root ganglion (DRG) neurons may control firing of these neurons by an autofeedback mechanism. In this study we used patch clamp recording techniques to determine if NKs alter excitability of rat L4-S3 DRG neurons by modulating K(+) currents. In capsaicin (CAPS)-responsive phasic neurons substance P (SP) lowered action potential (AP) threshold and increased the number of APs elicited by depolarizing current pulses. SP and a selective NK(2) agonist, [betaAla(8)]-neurokinin A (4-10) also inhibited low threshold inactivating K(+) currents isolated by blocking non-inactivating currents with a combination of high TEA, (-) verapamil and nifedipine. Currents recorded under these conditions were heteropodatoxin-sensitive (Kv4 blocker) and alpha-dendrotoxin-insensitive (Kv1.1 and Kv1.2 blocker). SP and NKA elicited a >10 mV positive shift of the voltage dependence of activation of the low threshold currents. This effect was absent in CAPS-unresponsive neurons. The effect of SP or NKA on K(+) currents in CAPS-responsive phasic neurons was fully reversed by an NK(2) receptor antagonist (MEN10376) but only partially reversed by a PKC inhibitor (bisindolylmaleimide). An NK(1) selective agonist ([Sar(9), Met(11)]-substance P) or direct activation of PKC with phorbol 12,13-dibutyrate, did not change firing in CAPS-responsive neurons, but did inhibit various types of K(+) currents that activated over a wide range of voltages. These data suggest that the excitability of CAPS-responsive phasic afferent neurons is increased by activation of NK(2) receptors and that this is due in part to inhibition and a positive voltage shift in the activation of heteropodatoxin-sensitive Kv4 channels.

The solubilization of pyrene in aqueous solution of beta-cyclodextrin (beta-CD) or its derivatives such as beta-CD-hexanoyl, beta-CD-benzoyl and beta-CD-dodecylsulfonate was investigated by spectrophotometry. Linear and non-linear regression methods were used to estimate the association constants (K(1)). A 1:1 stoichiometric ratio and different effects of the hexanoyl, benzoyl and dodecylsulfonate groups on the association constant were observed for the binary inclusion complex between pyrene and beta-CD. The formation constant was shown to decrease when beta-CD was modified by a dodecylsulfonate chain. The value of K(1) was 190+/-10 L mol(-1) for the [pyrene/beta-CD] complex and 145 L mol(-1) for the [pyrene/beta-CD-dodecylsulfonate] complex. Partitioning of the pyrene molecules between the dodecylsulfonate chains and cyclodextrin cavities can explain the decrease in the association constant value. In the cases of beta-CD-hexanoyl and beta-CD-benzoyl derivatives, no association constants were detected. Results suggest that the high hydrophobicity of the hexanoyl and benzoyl groups prevents the inclusion of pyrene molecules inside the cyclodextrin cavity.

The effect of perfluorooctanesulphonic acid (PFOS) on lipid membranes was studied using supported 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) bilayer as the model membrane. Phospholipid bilayer was deposited on gold electrode using a combination of the Langmuir-Blodgett and Langmuir-Schaefer (LB/LS) techniques. Electrodes were modified with two different types of membranes: DMPC bilayers initially containing PFOS and pure DMPC bilayers later exposed to the PFOS solutions. Such approach allowed studying both the changes in membrane characteristic imposed by the perfluorinated compound present in the model membrane and the process of its incorporation into the membrane. Studies with anticancer drug doxorubicin revealed that PFOS inhibits drug transport through the phospholipid bilayer and its effect can be compared to that of cholesterol. Moreover, the different trends observed in the changes in electron transfer rate constant (k(s)) calculated for ferricyanides and in peak current of hexaamineruthenium chloride showed that electrostatic interactions between electroactive probes and PFOS molecules incorporating into phospholipid bilayers play an important role and should be taken into account while explaining the interactions of perfluorooctanesulphonic acid with model biological membranes.

Cerebral ischemia/reperfusion (I/R) results in cellular energy failure and dysfunction of the neurovascular unit that contribute to subsequent neuronal cell death in the neonate. PX-18 is a putative neuroprotective inhibitor of secretory phospholipase A(2) (sPLA(2)) but its in vivo testing has been limited by its poor solubility. Our purpose was to assess whether PX-18 preserved neuronal-vascular reactivity to I/R-sensitive endothelium-dependent (hypercapnia, bradykinin) and/or neuron-dependent (N-methyl-D-aspartate; NMDA) stimuli. To make the drug available for in vivo studies, PX-18 was formulated as a 3% nanosuspension applying high pressure homogenization. Newborn piglets (1-day old, n=40) were anesthetized and ventilated, and cerebrovascular reactivity to the above stimuli was determined by measuring changes in pial arteriolar diameters using the closed cranial window/intravital videomicroscopy technique. Intravenous infusion of PX-18 nanosuspension (6 mg/kg, 20 min) did not affect baseline arteriolar diameters, or hypercapnia-, bradykinin-, or NMDA-induced pial arteriolar vasodilation under normoxic conditions. Global cerebral ischemia (10 min) followed by 1 h of reperfusion significantly attenuated hypercapnia-, bradykinin-, and NMDA-induced vasodilation in untreated or vehicle-treated controls. However, PX-18 resulted in nearly full preservation of cerebrovascular reactivity to all these stimuli. In conclusion, inhibition of sPLA(2) by PX-18 improves neurovascular function both at the neuronal and the microvascular level following I/R. This effect of PX-18 likely contributes to its neuroprotective effect.

The group IIA secretory phospholipase A2 (sPLA(2)-IIA) has been studied extensively because of its involvement in inflammatory processes. Up-regulation of this enzyme has been shown in a number of neurodegenerative diseases including cerebral ischemia and Alzheimer's disease. PX-18 is a selective sPLA(2) inhibitor effective in reducing tissue damage resulting from myocardial infarction. However, its use as a neuroprotective agent has been hampered due to its low solubility. In this study, we test the possible neuroprotective effects of PX-18 formulated as a suspension of nanocrystals. Transient global cerebral ischemia was induced in gerbils by occlusion of both common carotid arteries for 5 min. Four days after ischemia/reperfusion (I/R), extensive delayed neuronal death, DNA damage, and increases in reactive astrocytes and microglial cells were observed in the hippocampal CA1 region. PX-18 nanocrystals (30 and 60 mg/kg body wt) and vehicle controls were injected i.p. immediately after I/R. PX-18 nanocrystal injection significantly reduced delayed neuronal death, DNA damage, as well as glial cell activation. These findings demonstrated the effective neuroprotection of PX-18 in the form of nanocrystal against I/R-induced neuronal damage. The results also suggest that nanocrystals hold promise as an effective strategy for the delivery of compounds with poor solubility that would otherwise be precluded from preclinical development.

A nonmotile, nonspore-forming, Gram-negative, aerobic, small rod-shaped bacterium, isolated from soil, was identified as Chryseobacterium gleum on the basis of 16S rRNA gene sequence analysis. It was observed to grow luxuriously at pH 9 and tolerate highly alkaline environment up to pH 12. Orange red color was a peculiar character of these cells which on purification obtained 60-80 mg/l and found to be sphingosine type of sulfonolipid "sulfobacin A" on the basis of infrared, nuclear magnetic resonance, and mass spectral data. Inhibition of sulfobacin A synthesis by incorporation of L: -cycloserine in culture growth medium suggested presence of serine palmitoyl transferase which is one of the important enzymes involved in its biosynthesis. Sulfobacin A from C. gleum LMG P-22264 exhibited cytotoxicity against four cell lines tested. Maximum activity against human mammary adenocarcinoma cells was indicative of its potential as an anticancer agent.

Sewage sludge applied to soils as a fertilizer often contains metals and linear alkylbenzene sulphonate (LAS) as contaminants. These pollutants can be transported to the aquatic environment where they can alter the phosphatase activity in living organisms. The acid phosphatase of algae plays important roles in metabolism such as decomposing organic phosphate into free phosphate and autophagic digestive processes. The order of in vitro inhibition of Pseudokirchneriella subcapitata acid phosphatase at the highest concentration tested was LAS > Hg2+ = Al3+ > Se4+ = Pb2+ > Cd2+. A non-competitive inhibition mechanism was obtained for Hg2+ (Ki = 0.040 mM) and a competitive inhibition for LAS (Ki = 0.007 mM). In vivo studies with treated algae cultures showed that the inhibition of specific activity was observed in algae exposed during 7 days, in contrast to short term (24 h) treatments with both these chemicals. Our results suggest that the inhibition parameters in vitro did not markedly differ between the two chemicals. On the other hand, in vivo evaluations showed strong differences between both pollutants regarding the concentration values and the degree of response.

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are environmental contaminants found in the tissues of humans and wildlife. They are activators of peroxisome proliferator-activated receptor-alpha (PPAR alpha) and exhibit hepatocarcinogenic potential in rats. PFOS and PFOA are also developmental toxicants in rodents and PFOS has been shown to induce pulmonary deficits in rat offspring. Pregnant CD-1 mice were dosed with 0, 5, or 10mg/kg PFOS from gestation days 1-17. Transcript profiling was conducted on the fetal liver and lung. Results were contrasted to data derived from a previous PFOA study. PFOS-dependent changes were primarily related to activation of PPAR alpha. No remarkable differences were found between PFOS and PFOA. Given that PPAR alpha signaling is required for neonatal mortality in PFOA-treated mice but not those exposed to PFOS, the neonatal mortality observed for PFOS may reflect functional deficits related to the physical properties of the chemical rather than to transcript alterations.

Perfluorooctanesulfonate (PFOS), a persistent and accumulative compound, is widely distributed in humans and wildlife. Human exposure can occur early in development, as evidenced by the detection of PFOS in umbilical cord blood and breast milk. As part of a developmental neurotoxicology study for which developmental endpoints, including those related to the developing nervous system, have been reported separately, groups of 25 pregnant Sprague Dawley rats were given daily oral doses of either vehicle control or potassium PFOS (K(+)PFOS) at 0.1, 0.3, and 1.0mg/kg-d from gestation day (GD) 0 (day positive for mating) through postnatal day (PND) 20. An additional 10 pregnant females per treatment group were treated through GD 19 and sacrificed on GD 20 in order to obtain maternal and fetal serum and tissue samples at the end of gestation. The present paper reports the results of samples of serum, liver, brain, and thyroid glands taken at various times to evaluate: (1) serum, liver, and brain PFOS concentrations by LC-MS/MS to establish the relationship between PFOS concentrations and study outcomes; (2) serum thyrotropin (TSH) concentrations by RIA; (3) thyroid follicular cell proliferation index by Ki-67 immunohistochemical staining; (4) thyroid follicle epithelial cell height and colloidal area by histomorphometric analysis; (5) selected liver mRNA transcripts by quantitative RT-PCR. PFOS concentrations in dam and pup serum, liver, and brain increased across treatment groups in approximate proportion to the proportional increases in maternal K(+)PFOS dose, and sex differences in PFOS concentrations were not apparent in pups on PND 21. In pups from K(+)PFOS maternal dose groups on PND 72, serum PFOS had decreased to about 3 and 11% of PND 21 concentrations in males and females, respectively, and liver PFOS had decreased to about 17% of PND 21 concentrations in both sexes. Liver PFOS concentrations were approximately 0.6-0.8 times serum PFOS in GD 20 fetuses, and increased to about 2-4 times serum concentrations on PND 4 and 21. GD 20 fetal and PND 4 pup brain PFOS concentrations were approximately 33% of the corresponding serum concentrations, dropping to approximately 10% by PND 21, in contrast to dam brain PFOS concentrations, which were approximately 4-9% of serum PFOS concentrations. Compared to controls, Cyp2b2 mRNA was increased (2.8-fold) in the 1.0mg/kg-d treatment-group dams on GD 20. In male pups on PND 21, Cyp4A1, ACoA, and Cyp2b2 were increased 2.1-, 1.5-, and 1.8-fold, respectively, and Cyp7A1 was decreased 3.5-fold. Serum TSH and thyroid follicular morphology were not altered by K(+)PFOS treatment. The mean number of proliferating thyroid follicular cells was increased 2.1-fold over control in GD 20 female fetuses from 1.0mg/kg-d-treated dams, yet the highest individual count was similar to that of controls (116 versus 113 in controls).

Studies show that perfluorinated compounds cause various toxicological effects; nevertheless, effects on immune function and developmental endpoints have not been addressed at length. This study examined the effects of perfluorooctane sulfonate (PFOS) in white leghorn hatchlings on various developmental, immunological, and clinical health parameters. In addition, serum PFOS concentrations were determined by LC/MS/MS. Embryonic day (ED) 0 eggs were injected with either safflower oil/10% DMSO (control, 0mg/kg egg wt) or PFOS in safflower oil/10% DMSO at 1, 2.5, or 5mg/kg egg wt, and the chicks were grown to post-hatch day (PHD) 14. Treatment with PFOS did not affect hatch rate. Following in ovo exposure chicks exhibited increases in spleen mass at all treatment levels, in liver mass at 2.5 and 5mg/kg egg wt, and in body length (crown-rump length) at the 5mg/kg treatment. Right wings were shorter in all treatments compared to control. Increases in the frequency of brain asymmetry were evident in all treatment groups. SRBC-specific immunoglobulin (IgM and IgY combined) titers were decreased significantly at all treatment levels, while plasma lysozyme activity was increased at all treatment levels. The PHA skin test response decreased in relation to increasing PFOS dose. Serum concentrations where significant immunological, morphological, and neurological effects were observed at the lowest dose (1mg/kg egg wt) averaged 154 ng PFOS/g serum. These concentrations fall within environmental ranges reported in blood samples from wild caught avian species; thereby, verifying that the environmental egg concentrations used for the injections do indeed relate to serum levels in hatchlings that are also environmentally relevant. These data indicate that immune alterations and brain asymmetry can occur in birds following in ovo exposure to environmentally relevant concentrations of PFOS and demonstrates the need for further research on the developmental effects of perfluorinated compounds in various species.

Epidemiologists began to focus on human developmental outcomes with perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) as a consequence of dose-dependent developmental toxicological studies that reported effects of lowered birth weight, increased postnatal mortality, and decreased postnatal growth in surviving rats and mice. Contributing to the epidemiologic interest was the widespread presence of PFOS and PFOA in the general population, lengthy serum elimination half-lives in humans, and the placental transfer of PFOS and PFOA in humans that was established via measurement of paired maternal and umbilical cord blood samples. The purpose of this paper is to qualitatively review the published epidemiologic literature as it pertains to the potential association of exposure to PFOS and PFOA with human fetal development. The published research has focused on birth weight and other measurements that reflect human fetal development. A total of eight epidemiologic studies were reviewed that focused on six general (non-occupational) and two occupational populations. Of the six general population studies, five examined associations between birth weight and other anthropometric measurements in relation to maternal blood and/or umbilical cord concentrations of PFOS and PFOA. In the sixth study, three geographical areas in Washington County, Ohio, were categorized by their public drinking water sources that contained PFOA that had resulted in higher serum concentrations than observed in other general population studies. The occupational studies focused on a perfluorochemical manufacturing site (Decatur, AL) with exposure categorized from work history and biomonitoring data. There were inconsistent associations reported for several different birth outcomes, including birth weight, birth length, head circumference, and ponderal index, among the five general population studies that measured PFOS and PFOA in the study subjects. No association with birth weight or gestational age was reported in the community drinking water study. Only one general population study examined infant Apgar scores and developmental milestones at 6 and 18 months of age with no associations reported. No association with self-reported birth weight and occupational exposure to PFOS materials was observed among female perfluorochemical production workers. These epidemiologic data are discussed in relation to their methodological strengths and weaknesses, coherence with toxicological results, consistency of associations between studies, and plausible alternative explanations. Epidemiological, clinical, and toxicological insights are offered that may be useful for human health risk characterization. Studies scheduled for completion in the next few years are also cited. An appendix to this review describes the results of the only investigation that attempted to determine whether a causal association existed between maternal (4-14 weeks gestation) PFOS and PFOA concentrations in a general population and fecundity, as measured by time to pregnancy (TTP). Important issues are addressed regarding the methods and data analysis that may limit inferences from this particular study.

The dynamics of red cell shape changes following transfer into sucrose media having a low chloride content was studied. Based on a large number of measurements, six types of morphological response (MR), differing both in the degree of shape changes and the time course of the process, were identified. The most prominent type of response is a triphasic sequence of shape changes consisting of a fast transformation into a sphere (phase 1), followed by restoration of the discoid shape (phase 2) and final transformation into spherostomatocytes (phase 3), with individual parameters which could vary significantly. It was found that individual morphological response exhibited day to day variations, depending on the initial state of the red blood cells and the donor, but to a larger extent depended on the composition of the sucrose solution, such as concentration and type of buffers, the presence of EDTA, calcium, as well as very small amounts of extracellular hemoglobin. MR shows strong pH and ionic strength dependence. Low pH inhibited phase 1 and high pH changed dramatically the time course of the response. Increasing ionic strength inhibited all phases of MR, and at concentrations above 10-20 mM NaCl it was fully suppressed. Tris and phosphate were also inhibitory whereas HEPES, MOPS and Tricine were less effective. MR occurred also in hypertonic or hypotonic sucrose solutions, with exception of extreme hypotonicity due to volume restrictions. It is concluded that strong membrane depolarization per se is not a causal factor leading to MR, and its different phases could be regulated independently. For some types of morphological response the fast shape transformation from sphere to disc and back to sphere occurs within a 10 s time interval and could be accelerated several fold in the presence of a small amount of hemoglobin. It is suggested that MR represents a type of general cell reaction that occurs upon exposure to low ionic strength.

In this study we investigated the effect of a single-compound exposure or two compound co-exposure to tetrachlorodibenzo-p-dioxin (TCDD) plus perfluorooctane sulfonate (PFOS) or perfluorooctanoic acid (PFOA) on the mRNA expression of cytochromes P450 (CYP) 1A4, 4V2 and 3A37, ethoxyresorufin-O-deethylase (EROD) activity and cell viability in chicken (Gallus gallus domesticus) embryo primary hepatocyte cultures. Cell viability after 24 h of incubation was significantly decreased in cells exposed to PFOS at concentrations between 30 microM and 60 microM with or without co-exposure to TCDD (0.3 nM at maximum). PFOA did not decrease cell viability even at maximum concentrations of 60 microM. TCDD induced CYP1A4 mRNA and EROD activity substantially as reported previously. PFOS also increased CYP1A4 mRNA in a concentration-dependent manner. Co-exposure of cells to PFOS plus TCDD did not change CYP1A4 mRNA levels compared to cells treated with TCDD alone. PFOS alone did not induce CYP4V2 mRNA, however 40-50 microM PFOS plus TCDD (0.3 nM) induced CYP4V2 mRNA compared to TCDD alone (P<0.05). This trend was similar to that observed with co-exposure to TCDD plus PFOA, suggesting that PFOA alone did not induce CYP4V2 mRNA, whereas co-exposure to TCDD plus PFOA induced the expression levels. PFOS alone decreased CYP3A37 mRNA by a maximum of 45%, however after co-exposure to TCDD, recovery of mRNA expression to levels measured in DMSO-treated cells was observed. Our data suggest a complex gene response to mixtures of dioxin-like and perfluorinated compounds.

Perfluorooctane sulfonate (PFOS) was evaluated alone and in binary mixtures with pentachlorophenol, atrazine and diuron, respectively to investigate the effects of interactions between PFOS and other compounds on the growth rate in Scenedesmus obliquus. Single application of PFOS showed no inhibition on the growth of S. obliquus below 40 mg L(-1), whereas PFOS acting with pentachlorophenol resulted in higher algal growth inhibition in comparison with pentachlorophenol alone. A maximum increase of 45% in the growth inhibition was observed at a pentachlorophenol concentration of 2.56 mg L(-1) together with a PFOS concentration of 40 mg L(-1). On the contrary, the algal growth inhibition of atrazine and diuron was depressed by PFOS. Furthermore, cell uptake was examined to gain some insights into the mechanisms of the effects of PFOS on the toxicity of the other compounds. Cell uptake of pentachlorophenol increased while that of atrazine and diuron was reduced in cells that have been exposed to PFOS. The effects of PFOS on the toxicity of pentachlorophenol, atrazine and diuron were possibly related to the influence of PFOS on the cell uptake of these hydrophobic compounds. Results suggested that PFOS influenced the cell uptake and toxicity of structurally different compounds in dissimilar manners and potentially increased the accessibility and toxicity of more hydrophobic compounds to algal cells.

The discharge of untreated detergent-bearing waste introduces linear alklcylbenzene sulfonates (LAS) to the aquatic environment. The surfactant persists in some streams and rivers in Nigeria, some is adsorbed to suspended materials and end in the sediment of the receiving water bodies. In this study, bacteria isolated from sediments of some tropical detergent-effluent-polluted streams were tested for tolerance to LAS using the media dilution technique. LAS-tolerance was indicated by growth of the bacteria in the presence of the surfactant. The pH, concentrations of surfactant, population of heterotrophic bacteria and population of LAS-tolerant bacteria in the sediments were determined. A direct relationship (r = 0.9124) was found between the alkaline conditions (pH= 8.2-12.0) and high surfactant concentrations (45-132 mg/g) in the sediment. The sediments harboured a high population and a wide variety of bacteria; the populations of viable heterotrophic bacteria (VHB: 2.9 x 10(5) to 1.2 x 10(7) cfu/g) and LAS tolerant bacteria (LTB: 1.5 x 10(4) to 1.2 x 10(6) cfu/g) had a direct relationship (r = 0.9500). An inverse relationship resulted between each of them and the concentration of surfactant in the sediment, r(VHB/LAS) = -0.9303 and r(LTB/LAS) = -0.9143, respectively. Twelve bacteria species were isolated from the sediment: Alcaligenes odorans, Bacillus subtilis, Burkholderia cepacia, Citrobacter freundii, Citrobacter diversus, Escherichia coli, Micrococcus luteus, Micrococcus albus, Pseudomonas putida, Pseudomonas stutzeri, Staphylococcus aureus and Streptococcusfaecalis. Most of them were adapted to the surfactant with their maximum acceptable concentrations ranging between 0.03 and >1.0% (w/v). The sediments could serve as source of adapted organisms which can be used in bio-treatment of LAS-bearing waste.

Understanding the membrane solubilization process and finding effective solubilizing agents are crucial challenges in biochemical research. Here we report results on the interaction of the novel linear alkylamido propyl dimethyl amino propanosulfonate detergents, ASB-14 and ASB-16, with human erythrocyte membranes. An estimation of the critical micelle concentration of these zwitterionic detergents (ASB-14 = 100 microM and ASB-16 = 10 microM) was obtained using electron paramagnetic resonance. The amount of proteins and cholesterol solubilized from erythrocytes by these detergents was then determined. The hemolytic activities of the ASB detergents were assayed and the detergent/lipid molar ratios for the onset of hemolysis (Re sat) and total lysis (Re sol) were calculated, allowing the determination of the membrane binding constants (Kb). ASB-14 presented lower membrane affinity (Kb = 7050 M(-1)) than ASB-16 (Kb = 15610 M(-1)). The amount of proteins and cholesterol solubilized by both ASB detergents was higher while Re sat values (0.22 and 0.08 detergent/lipid for ASB-14 and ASB-16, respectively) were smaller than those observed with the classic detergents CHAPS and Triton X-100. These results reveal that, besides their well-known use as membrane protein solubilizers to enhance the resolution of two dimensional electrophoresis/mass spectrometry, ASB-14 and ASB-16 are strong hemolytic agents. We propose that the physicochemical properties of ASB detergents determine their membrane disruption efficiency and can help to explain the improvement in the solubilization of membrane proteins, as reported in the literature.

Perfluorooctane sulfonate (PFOS) is a globally distributed environmental contaminant that is detected in the serum and liver of numerous mammalian and avian species. PFOS acts as a peroxisome proliferator in rodents, which occurs subsequent to activation of the nuclear receptor peroxisome proliferator activated receptor-alpha (PPAR-alpha). Activated PPAR-alpha up-regulates PPAR-alpha target genes, most of which are involved in lipid metabolism. Although several studies have investigated the effects of PFOS exposure on mammalian gene expression, there are few studies in avian species. To determine if PFOS is capable of activating avian PPAR-alpha, we exposed chicken embryo primary hepatocyte cultures (N=3 independent cell cultures) to PFOS or fenofibrate, a mammalian PPAR-alpha agonist, and examined the expression of PPAR-alpha and PPAR-alpha target genes using quantitative real-time PCR. The target genes examined were peroxisomal acyl-CoA oxidase (ACOX), liver fatty acid binding protein (L-FABP), enoyl-Coenzyme A, hydratase/3-hydroxyacyl Coenzyme A dehydrogenase bifunctional enzyme (BIEN), peroxisomal 3-ketoacyl thiolase (PKT), and malic enzyme (ME). All five target genes were induced in response to PFOS exposure and all of the target genes, except L-FABP, were induced in response to fenofibrate. PPAR-alpha mRNA expression was not altered by PFOS or fenofibrate. This study provides the first evidence that PFOS can induce PPAR-alpha-dependent transcriptional responses in an avian species and provides the first characterization of fenofibrate induced transcriptional responses in chicken embryo hepatocyte cultures.

Aims: To isolate and identify linear alkylbenzene sulfonate (LAS)-degrading bacteria from Río de la Plata and adjacent waters, and to assay their degradation capability as a consortium and as single organisms., Methods and Results: A consortium consisting of four bacterial strains: Aeromonas caviae (two strains), Pseudomonas alcaliphila and Vibrio sp. was identified by 16S rRNA analysis. Isolates grown as a consortium produced higher biomass from LAS and CO(2) release (mineralization) than individual cultures, and degraded 86% of LAS (20 mg l(-1)), whereas pure strains degraded between 21% and 60%. Bacterial desulfonation from LAS was evidenced in the consortium and A. caviae strains. A complete disappearance of LAS (10 mg l(-1)) was accomplished, and LAS levels of 50 and 100 mg l(-1) led to a pronounced decrease in the biodegradation extent and inhibition of culture growth., Conclusions: A bacterial consortium capable of complete LAS degradation was isolated from the Río de la Plata and adjacent waters. This consortium was more efficient for LAS degradation than individual cultures, and was sensitive to high LAS concentrations., Significance and Impact of the Study: The autochthonous consortium with high effectiveness on LAS biodegradation is a useful tool for LAS depletion from these polluted ecosystems.

Perfluorooctane sulfonate (PFOS) is a persistent and bioaccumulative pollutant ubiquitous in wildlife and humans. Although the distribution and fate of PFOS have been widely studied, its potential neurotoxicity remains largely unknown. In the present study, the acute and chronic effects of PFOS on the development and synaptic transmission of hippocampal neurons was examined. Perfusion with PFOS markedly increased the frequency of miniature postsynaptic currents (mPSCs) and slightly elevated the amplitude of mPSCs in cultured hippocampal neurons. Perfusion with PFOS also increased the amplitude of field excitatory postsynaptic potentials (fEPSPs) recorded in the CA1 region of hippocampal slices. Both of these effects were largely blocked by the L-type Ca2+ channel antagonist nifedipine. Further studies showed that PFOS enhanced inward Ca2+ currents and increased intracellular Ca2+ in cultured neurons; these effects were also substantially inhibited by nifedipine. Moreover, prolonged treatment with PFOS moderately inhibited neurite growth and dramatically suppressed synaptogenesis in cultured neurons in a nifedipine-sensitive manner. Thus, through enhancement of Ca2+ channels, PFOS may exhibit both acute excitotoxic effects on synaptic function and chronically inhibit synaptogenesis in the brain.

Perfluorooctanoate (PFOA) and perfluorooctanesulfonate (PFOS) are widespread persistent organic pollutants that have been associated with reduced birth weight at doses expected in many pregnant populations. The authors randomly selected 1,400 pregnant women and their newborns from the Danish National Birth Cohort (1996-2002) to investigate whether these compounds reduce organ growth. PFOS and PFOA were measured in maternal blood samples taken early in pregnancy. Placental weight, birth length, and head and abdominal circumferences were measured shortly after birth by trained midwives or nurses. Maternal PFOA levels in early pregnancy were associated with smaller abdominal circumference and birth length. For each ng/ml increase in PFOA, birth length decreased by 0.069 cm (95% confidence interval: 0.024, 0.113) and abdominal circumference decreased by 0.059 cm (95% confidence interval: 0.012, 0.106). An inverse association was also observed between PFOA and placental weight and head circumference, and a positive association was observed with newborn ponderal index, but none of these associations was statistically significant. Maternal PFOS levels were not associated with any of the five fetal growth indicators. These findings suggest that fetal exposure to PFOA but not PFOS during organ development may affect the growth of organs and the skeleton.

Linear alkylbenzene sulfonates (LAS) constitute, quantitatively, the most important group of synthetic surfactants used today. We studied the gene expression of Nitrosomonas europaea in response to LAS using a DNA microarray because ammonia-oxidizers are thought to be more sensitive to LAS than other microorganisms. Our objective was to elucidate which genes are expressed for N. europaea in response to LAS exposure. Microarray analysis and real-time PCR assay revealed that c. 30 genes were significantly expressed after LAS exposure, in particular genes associated with energy production and conversion. Our findings demonstrate that physical disruption of membrane structures, which contain enzymes associated with energy production and conversion, might be an important explanation for the high sensitivity of N. europaea to LAS exposure.