Organochlorine pesticides and their metabolites in human breast milk from Shanghai, China.

PubMed

Lu, Dasheng; Wang, Dongli; Ni, Rong; Lin, Yuanjie; Feng, Chao; Xu, Qian; Jia, Xiaodong; Wang, Guoquan; Zhou, Zhijun

2015-06-01

Organochlorine pesticides (OCPs) are persistent organic pollutants that could cause deleterious effects on human health. Breast milk represents a noninvasive specimen source to assess maternal and infant exposure to OCPs. This study recruited 142 pregnant mothers in 2011-2012 in Shanghai, China, and their breast milk samples were collected during lactation and analyzed for 27 OCP compounds. Detection rates were in a range of 65.5 to 100 %. In particular, metabolites of 2,2-bis(chlorophenyl)-1,1,1-trichloroethane (DDT) such as 2-chloro-1,1-bis(4-chlorophenyl)ethylene (DDMU), 2,2-bis(4-chlorophenyl)ethanol (DDOH), bis(4-chlorophenyl)ketone (DBP), and 4,4'-dichlorodiphenylmethane (DDM) were detected in most milk samples. DDTs, hexachlorobenzene (HCB), and hexachlorocyclohexane (HCH) were dominant OCPs with mean levels of 316, 49.8, and 41.5 ng/g lipid content, respectively, whereas levels of methoxychlor, ∑Drins, ∑Heptachlor, ∑Chlordane, and ∑Endosulfan were fairly low (0.87-5.6 ng/g lipid content). Milk concentrations of OCPs were weakly correlated with maternal age, body weight, and body mass indexes (BMIs). ∑OCPs in this study were much lower than those in human breast milk samples collected in 2002 and 2007. Consumption of higher amounts of fish was associated with higher milk levels of OCPs. Specific OCP patterns in breast milk samples from migrant mothers in Shanghai reflected features of OCP production, use, and exposure in their home provinces. The probabilistic exposure assessment model reveals that Shanghai infants were exposed to low levels of OCPs through breast milk consumption. However, infants as the vulnerable group might be subject to the potential additive and/or synergistic health effects from complex OCP exposure.

Biophysical modeling of in vitro and in vivo processes underlying regulated photoprotective mechanism in cyanobacteria.

PubMed

Shirshin, Evgeny A; Nikonova, Elena E; Kuzminov, Fedor I; Sluchanko, Nikolai N; Elanskaya, Irina V; Gorbunov, Maxim Y; Fadeev, Victor V; Friedrich, Thomas; Maksimov, Eugene G

2017-09-01

Non-photochemical quenching (NPQ) is a mechanism responsible for high light tolerance in photosynthetic organisms. In cyanobacteria, NPQ is realized by the interplay between light-harvesting complexes, phycobilisomes (PBs), a light sensor and effector of NPQ, the photoactive orange carotenoid protein (OCP), and the fluorescence recovery protein (FRP). Here, we introduced a biophysical model, which takes into account the whole spectrum of interactions between PBs, OCP, and FRP and describes the experimental PBs fluorescence kinetics, unraveling interaction rate constants between the components involved and their relative concentrations in the cell. We took benefit from the possibility to reconstruct the photoprotection mechanism and its parts in vitro, where most of the parameters could be varied, to develop the model and then applied it to describe the NPQ kinetics in the Synechocystis sp. PCC 6803 mutant lacking photosystems. Our analyses revealed  that while an excess of the OCP over PBs is required to obtain substantial PBs fluorescence quenching in vitro, in vivo the OCP/PBs ratio is less than unity, due to higher local concentration of PBs, which was estimated as ~10 -5 M, compared to in vitro experiments. The analysis of PBs fluorescence recovery on the basis of the generalized model of enzymatic catalysis resulted in determination of the FRP concentration in vivo close to 10% of the OCP concentration. Finally, the possible role of the FRP oligomeric state alteration in the kinetics of PBs fluorescence was shown. This paper provides the most comprehensive model of the OCP-induced PBs fluorescence quenching to date and the results are important for better understanding of the regulatory molecular mechanisms underlying NPQ in cyanobacteria.

Air-Seawater Exchange of Organochlorine Pesticides along the Sediment Plume of a Large Contaminated River.

PubMed

Lin, Tian; Guo, Zhigang; Li, Yuanyuan; Nizzetto, Luca; Ma, Chuanliang; Chen, Yingjun

2015-05-05

Gaseous exchange fluxes of organochlorine pesticides (OCPs) across the air-water interface of the coastal East China Sea were determined in order to assess whether the contaminated plume of the Yangtze River could be an important regional source of OCPs to the atmosphere. Hexachlorocyclohexanes (HCHs), chlordane compounds (CHLs), and dichlorodiphenyltrichloroethanes (DDTs) were the most frequently detected OCPs in air and water. Air-water exchange was mainly characterized by net volatilization for all measured OCPs. The net gaseous exchange flux ranged 10-240 ng/(m2·day) for γ-HCH, 60-370 ng/(m2·day) for trans-CHL, 97-410 ng/(m2·day) for cis-CHL, and ∼0 (e.g., equilibrium) to 490 ng/(m2·day) for p,p'-DDE. We found that the plume of the large contaminated river can serve as a significant regional secondary atmospheric source of legacy contaminants released in the catchment. In particular, the sediment plume represented the relevant source of DDT compounds (especially p,p'-DDE) sustaining net degassing when clean air masses from the open ocean reached the plume area. In contrast, a mass balance showed that, for HCHs, contaminated river discharge (water and sediment) plumes were capable of sustaining volatilization throughout the year. These results demonstrate the inconsistencies in the fate of HCHs and DDTs in this large estuarine system with declining primary sources.

Inflammatory arthritis increases mouse osteoclast precursors with myeloid suppressor function

PubMed Central

Charles, Julia F.; Hsu, Lih-Yun; Niemi, Erene C.; Weiss, Arthur; Aliprantis, Antonios O.; Nakamura, Mary C.

2012-01-01

Increased osteoclastic bone resorption leads to periarticular erosions and systemic osteoporosis in RA patients. Although a great deal is known about how osteoclasts differentiate from precursors and resorb bone, the identity of an osteoclast precursor (OCP) population in vivo and its regulatory role in RA remains elusive. Here, we report the identification of a CD11b–/loLy6Chi BM population with OCP activity in vitro and in vivo. These cells, which can be distinguished from previously characterized precursors in the myeloid lineage, display features of both M1 and M2 monocytes and expand in inflammatory arthritis models. Surprisingly, in one mouse model of RA (adoptive transfer of SKG arthritis), cotransfer of OCP with SKG CD4+ T cells diminished inflammatory arthritis. Similar to monocytic myeloid-derived suppressor cells (M-MDSCs), OCPs suppressed CD4+ and CD8+ T cell proliferation in vitro through the production of NO. This study identifies a BM myeloid precursor population with osteoclastic and T cell–suppressive activity that is expanded in inflammatory arthritis. Therapeutic strategies that prevent the development of OCPs into mature bone-resorbing cells could simultaneously prevent bone resorption and generate an antiinflammatory milieu in the RA joint. PMID:23114597

Fast Simulators for Satellite Cloud Optical Centroid Pressure Retrievals, 1. Evaluation of OMI Cloud Retrievals

NASA Technical Reports Server (NTRS)

Joiner, J.; Vasilkov, A.; Gupta, P.; Bhartia, P. K.; Veefkind, P.; Sneep, M.; de Haan, J.; Polonsky, I.; Spurr, R.

2012-01-01

The cloud Optical Centroid Pressure (OCP), also known as the effective cloud pressure, is a satellite-derived parameter that is commonly used in trace-gas retrievals to account for the effects of clouds on near-infrared through ultraviolet radiance measurements. Fast simulators are desirable to further expand the use of cloud OCP retrievals into the operational and climate communities for applications such as data assimilation and evaluation of cloud vertical structure in general circulation models. In this paper, we develop and validate fast simulators that provide estimates of the cloud OCP given a vertical profile of optical extinction. We use a pressure-weighting scheme where the weights depend upon optical parameters of clouds and/or aerosol. A cloud weighting function is easily extracted using this formulation. We then use fast simulators to compare two different satellite cloud OCP retrievals from the Ozone Monitoring Instrument (OMI) with estimates based on collocated cloud extinction profiles from a combination of CloudS at radar and MODIS visible radiance data. These comparisons are made over a wide range of conditions to provide a comprehensive validation of the OMI cloud OCP retrievals. We find generally good agreement between OMI cloud OCPs and those predicted by CloudSat. However, the OMI cloud OCPs from the two independent algorithms agree better with each other than either does with the estimates from CloudSat/MODIS. Differences between OMI cloud OCPs and those based on CloudSat/MODIS may result from undetected snow/ice at the surface, cloud 3-D effects, low altitude clouds missed by CloudSat, and the fact that CloudSat only observes a relatively small fraction of an OMI field-of-view.

The effect of a combination therapy with myo-inositol and a combined oral contraceptive pill versus a combined oral contraceptive pill alone on metabolic, endocrine, and clinical parameters in polycystic ovary syndrome.

PubMed

Minozzi, Massimo; Costantino, Demetrio; Guaraldi, Claudia; Unfer, Vittorio

2011-11-01

Compare the effects of a combined contraceptive pill (OCP) in combination with myo-inositol (MI) on endocrine, metabolic, and clinical parameters in patients with polycystic ovary syndrome (PCOS). One hundred fifty-five patients with PCOS were enrolled in this prospective, open-label clinical study. Patients were assigned to receive oral treatment with OCP alone (estradiol (EE) 30 μg/gestodene 75 μg) or in combination with myo-inositol 4 g/die, for 12 months. OCP plus MI therapy resulted in a higher reduction of FG score compared with OCP alone therapy. The combined therapy (OCP plus MI) significantly decreased hyperinsulinaemia, by positively affecting the fasting insulin and glucose levels and homeostasis model assessment-insulin resistance parameters, while no significant changes were observed in the OCP group. Androgens serum levels decreased in both groups, but significantly more in the combined therapy group. The lipid profile was improved in the combined therapy group, by reducing low-density lipoprotein cholesterol levels and enhancing high-density lipoprotein cholesterol levels. Our data show that a combination of combined contraceptive pill and MI may be more effective in controlling endocrine, metabolic, and clinical profile in patients with PCOS than OCP alone, and may reduce insulin levels and insulin resistance. Hence, combined treatment may become a more effective long-term therapeutic choice for controlling PCOS symptoms.

Body composition is improved during 12 months' treatment with metformin alone or combined with oral contraceptives compared with treatment with oral contraceptives in polycystic ovary syndrome.

PubMed

Glintborg, Dorte; Altinok, Magda Lambaa; Mumm, Hanne; Hermann, Anne Pernille; Ravn, Pernille; Andersen, Marianne

2014-07-01

Central obesity in polycystic ovary syndrome (PCOS) is associated with increased inflammatory markers and increased risk for type 2 diabetes. The objective of the study was to evaluate whether treatment with metformin (M) or M combined with oral contraceptive pills (OCPs) resulted in a more advantageous body composition than treatment with OCP alone. The study was conducted at an outpatient clinic. This was a randomized, controlled clinical trial. Ninety patients with PCOS were randomized to 12 months' treatment with M (2 g/d), M + OCP (150 mg desogestrel+30 μg ethinylestradiol), or OCP. Whole-body dual-energy x-ray absorptiometry scans and clinical and hormonal evaluations were performed before and after the intervention period. A total of 65 of 90 patients completed the study. Changes in weight at 6 and 12 months and changes in regional fat mass estimates at 12 months were measured. Dropout rates between intervention groups were not significantly different. Treatment with M and M+OCP were superior to OCP regarding weight and regional fat mass. The median (quartiles) weight changes during 12 months of M, M+OCP, and OCP treatment were -3.0 (-10.3; 0.6), -1.9 (-4.9; 0.1), and 1.2 (-0.8; 3.0) kg, respectively, P < .05. Upper to lower fat mass ratio was unchanged. Changes in body composition were predicted by the type of medical intervention (M, M+OCP, or OCP) and not by body mass index at study inclusion. OCP and M+OCP were superior to M regarding reduction in free T levels. M treatment alone or in combination with OCP was associated with weight loss and improved body composition compared with OCP, whereas free T levels decreased during M+OCP or OCP. Combined treatment with M+OCP should be considered as an alternative to treatment with OCP alone to avoid weight gain in PCOS.

Modeling of gene expression pattern alteration by p,p′-DDE and dieldrin in largemouth bass

PubMed Central

Garcia-Reyero, Natàlia; Barber, David; Gross, Timothy; Denslow, Nancy

2007-01-01

In this study, largemouth bass (LMB) were subchronically exposed to p,p′-DDE or dieldrin in their diet to evaluate the effect of exposure on expression of genes involved in reproduction and steroid homeostasis. Using real-time PCR, we detected a different gene expression pattern for each OCP, suggesting that they each affect LMB in a different way. We also detected a different expression pattern among sexes, suggesting that sexes are affected differently by OCPs perhaps reflecting the different adaptive responses of each sex to dysregulation caused by OCP exposure. PMID:16707152

Modeling of gene expression pattern alteration by p,p′-DDE and dieldrin in largemouth bass

USGS Publications Warehouse

Garcia-Reyero, Natalia; Barber, David; Gross, Timothy; Denslow, Nancy

2006-01-01

In this study, largemouth bass (LMB) were subchronically exposed to p,p′-DDE or dieldrin in their diet to evaluate the effect of exposure on expression of genes involved in reproduction and steroid homeostasis. Using real-time PCR, we detected a different gene expression pattern for each OCP, suggesting that they each affect LMB in a different way. We also detected a different expression pattern among sexes, suggesting that sexes are affected differently by OCPs perhaps reflecting the different adaptive responses of each sex to dysregulation caused by OCP exposure.

A novel role for cathepsin K in periosteal osteoclast precursors during fracture repair.

PubMed

Walia, Bhavita; Lingenheld, Elizabeth; Duong, Le; Sanjay, Archana; Drissi, Hicham

2018-03-01

Osteoporosis management is currently centered around bisphosphonates, which inhibit osteoclast (OC) bone resorption but do not affect bone formation. This reduces fracture risk, but fails to restore healthy bone remodeling. Studies in animal models showed that cathepsin K (CatK) inhibition by genetic deletion or chemical inhibitors maintained bone formation while abrogating resorption during bone remodeling and stimulated periosteal bone modeling. Recently, periosteal mononuclear tartrate-resistant acid phosphatase-positive (TRAP + ) osteoclast precursors (OCPs) were shown to augment angiogenesis-coupled osteogenesis. CatK gene deletion increased osteoblast differentiation via enhanced OCP and OC secretion of platelet-derived growth factor (PDGF)-BB and sphingosine 1 phosphate. The effects of periosteum-derived OCPs on bone remodeling are unknown, particularly with regard to fracture repair. We hypothesized that periosteal OCPs derived from CatK-null (Ctsk -/- ) mice may enhance periosteal bone formation during fracture repair. We found fewer periosteal OCPs in Ctsk -/- mice under homeostatic conditions; however, after fracture, this population increased in number relative to that seen in wild-type (WT) mice. Enhanced TRAP staining and greater expression of PDGF-BB were observed in fractured Ctsk -/- femurs relative to WT femurs. This early pattern of augmented PDGF-BB expression in Ctsk -/- mice may contribute to improved fracture healing by enhancing callus mineralization in Ctsk -/- mice. © 2018 New York Academy of Sciences.

Synthetic octacalcium phosphate-enhanced reparative dentine formation via induction of odontoblast differentiation.

PubMed

Wang, Xiaogu; Suzawa, Tetsuo; Miyauchi, Tomohiko; Zhao, Baohong; Yasuhara, Rika; Anada, Takahisa; Nakamura, Masanori; Suzuki, Osamu; Kamijo, Ryutaro

2015-11-01

Synthetic octacalcium phosphate (OCP) has been suggested to be a useful biomaterial for the regeneration of hard tissues, including bone. However, it remains unknown whether OCP induces dentine formation by dental pulp. We investigated biomineralization of dental pulp exposed to synthetic OCP in vitro and in vivo. When dental pulp was exposed directly to OCP, rapid formation of reparative dentine (RD) was induced and expression of dentine sialoprotein synthesis was observed in dental pulp adjacent to newly synthesized RD. OCP inhibited the proliferation of rat pulp cells and also promoted their odontoblastic differentiation in vitro, as alkaline phosphatase activity, mineralization of pulp cells and the expression level of dentine sialophosphoprotein were enhanced. Direct contact between OCP and pulp cells is required for OCP to exhibit its effects in vitro. The expression level of Runx2, a transcription factor whose downregulation is closely related to odontoblast differentiation, was downregulated in pulp cells cultured with OCP. Structural changes of OCP during culture were determined by Fourier transform infrared spectroscopy. OCP tended to be converted to carbonate hydroxyapatite after incubation with or without pulp cells, which may be analogous to biological apatite crystals. Taken together, our data suggest that synthetic OCP supports RD formation by dental pulp and downregulation of Runx2 may be involved in that stimulatory activity. Furthermore, OCP-apatite conversion is involved in this stimulatory capacity of OCP. Copyright © 2013 John Wiley & Sons, Ltd.

Unified concept of effective one component plasma for hot dense plasmas

DOE PAGES

Clerouin, Jean; Arnault, Philippe; Ticknor, Christopher; ...

2016-03-17

Orbital-free molecular dynamics simulations are used to benchmark two popular models for hot dense plasmas: the one component plasma (OCP) and the Yukawa model. A unified concept emerges where an effective OCP (EOCP) is constructed from the short-range structure of the plasma. An unambiguous ionization and the screening length can be defined and used for a Yukawa system, which reproduces the long-range structure with finite compressibility. Similarly, the dispersion relation of longitudinal waves is consistent with the screened model at vanishing wave number but merges with the OCP at high wave number. Additionally, the EOCP reproduces the overall relaxation timemore » scales of the correlation functions associated with ionic motion. Lastly, in the hot dense regime, this unified concept of EOCP can be fruitfully applied to deduce properties such as the equation of state, ionic transport coefficients, and the ion feature in x-ray Thomson scattering experiments.« less

Human Elimination of Organochlorine Pesticides: Blood, Urine, and Sweat Study

PubMed Central

Lane, Kevin; Birkholz, Detlef

2016-01-01

Background. Many individuals have been exposed to organochlorinated pesticides (OCPs) through food, water, air, dermal exposure, and/or vertical transmission. Due to enterohepatic reabsorption and affinity to adipose tissue, OCPs are not efficiently eliminated from the human body and may accrue in tissues. Many epidemiological studies demonstrate significant exposure-disease relationships suggesting OCPs can alter metabolic function and potentially lead to illness. There is limited study of interventions to facilitate OCP elimination from the human body. This study explored the efficacy of induced perspiration as a means to eliminate OCPs. Methods. Blood, urine, and sweat (BUS) were collected from 20 individuals. Analysis of 23 OCPs was performed using dual-column gas chromatography with electron-capture detectors. Results. Various OCPs and metabolites, including DDT, DDE, methoxychlor, endrin, and endosulfan sulfate, were excreted into perspiration. Generally, sweat samples showed more frequent OCP detection than serum or urine analysis. Many OCPs were not readily detected in blood testing while still being excreted and identified in sweat. No direct correlation was found among OCP concentrations in the blood, urine, or sweat compartments. Conclusions. Sweat analysis may be useful in detecting some accrued OCPs not found in regular serum testing. Induced perspiration may be a viable clinical tool for eliminating some OCPs. PMID:27800487

Predicting maternal body burdens of organochlorine pesticides from eggs and evidence of maternal transfer in Alligator mississippiensis

USGS Publications Warehouse

Rauschenberger, R.H.; Sepulveda, M.S.; Wiebe, J.J.; Szabo, N.J.; Gross, T.S.

2004-01-01

Few data exist regarding maternal-embryonal transfer of organochlorine pesticides (OCPs) in reptiles. The objective of the present study was to evaluate maternal transfer of OCPs in American alligators (Alligator mississippiensis) from low-, intermediate-, and high-OCP-exposure sites. Overall, total OCP burdens ranged from less than 0.8 ppb in blood to more than 44,000 ppb in abdominal adipose tissue (wet wt concentrations). Lipid-adjusted ratios of maternal adipose burdens (total OCPs) to yolk burdens were close to one (0.94 ?? 0.31:1), suggesting that animals were in steady state and that OCPs in eggs originated from adipose lipids. In contrast, lipid-adjusted muscle and liver OCP burdens were greater than yolk OCP burdens, suggesting that lipids in muscle were not utilized during oogenesis and that nonlipid liver tissue sequesters OCPs. Predictive equations were derived for several tissues and several OCP analytes with r2 values ranging from 0.40 to 0.99 (p < 0.05). We suggest that yolk burdens are predictive of maternal tissue burdens for certain tissues and OCPs and that certain OCPs are maternally transferred in the American alligator. Furthermore, we suggest that future studies should investigate the applicability of these predictive equations for assessing maternal exposure in other crocodilian species.

Human Elimination of Organochlorine Pesticides: Blood, Urine, and Sweat Study.

PubMed

Genuis, Stephen J; Lane, Kevin; Birkholz, Detlef

2016-01-01

Background . Many individuals have been exposed to organochlorinated pesticides (OCPs) through food, water, air, dermal exposure, and/or vertical transmission. Due to enterohepatic reabsorption and affinity to adipose tissue, OCPs are not efficiently eliminated from the human body and may accrue in tissues. Many epidemiological studies demonstrate significant exposure-disease relationships suggesting OCPs can alter metabolic function and potentially lead to illness. There is limited study of interventions to facilitate OCP elimination from the human body. This study explored the efficacy of induced perspiration as a means to eliminate OCPs. Methods . Blood, urine, and sweat (BUS) were collected from 20 individuals. Analysis of 23 OCPs was performed using dual-column gas chromatography with electron-capture detectors. Results . Various OCPs and metabolites, including DDT, DDE, methoxychlor, endrin, and endosulfan sulfate, were excreted into perspiration. Generally, sweat samples showed more frequent OCP detection than serum or urine analysis. Many OCPs were not readily detected in blood testing while still being excreted and identified in sweat. No direct correlation was found among OCP concentrations in the blood, urine, or sweat compartments. Conclusions . Sweat analysis may be useful in detecting some accrued OCPs not found in regular serum testing. Induced perspiration may be a viable clinical tool for eliminating some OCPs.

Fluorinated End-Groups in Electrolytes Induce Ordered Electrolyte/Anode Interface Even at Open-Circuit Potential as Revealed by Sum Frequency Generation Vibrational Spectroscopy

DOE PAGES

Horowitz, Yonatan; Han, Hui-Ling; Ralston, Walter T.; ...

2017-05-12

Fluorine-based additives have a tremendously beneficial effect on the performance of lithium-ion batteries, yet the origin of this phenomenon is unclear. This study shows that the formation of a solid-electrolyte interphase (SEI) on the anode surface in the first five charge/discharge cycles is affected by the stereochemistry of the electrolyte molecules on the anode surface starting at open-circuit potential (OCP). This study shows an anode-specific model system, the reduction of 1,2-diethoxy ethane with lithium bis(trifluoromethane)sulfonimide, as a salt on an amorphous silicon anode, and compares the electrochemical response and SEI formation to its fluorinated version, bis(2,2,2-trifluoroethoxy) ethane (BTFEOE), by summore » frequency generation (SFG) vibrational spectroscopy under reaction conditions. The SFG results suggest that the —CF 3 end-groups of the linear ether BTFEOE change their adsorption orientation on the a-Si surface at OCP, leading to a better protective layer. Finally, supporting evidence from ex situ scanning electron microscopy and X-ray photoelectron spectroscopy depth profiling measurements shows that the fluorinated ether, BTFEOE, yields a smooth SEI on the a-Si surface and enables lithium ions to intercalate deeper into the a-Si bulk.« less

Fluorinated End-Groups in Electrolytes Induce Ordered Electrolyte/Anode Interface Even at Open-Circuit Potential as Revealed by Sum Frequency Generation Vibrational Spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Horowitz, Yonatan; Han, Hui-Ling; Ralston, Walter T.

Fluorine-based additives have a tremendously beneficial effect on the performance of lithium-ion batteries, yet the origin of this phenomenon is unclear. This study shows that the formation of a solid-electrolyte interphase (SEI) on the anode surface in the first five charge/discharge cycles is affected by the stereochemistry of the electrolyte molecules on the anode surface starting at open-circuit potential (OCP). This study shows an anode-specific model system, the reduction of 1,2-diethoxy ethane with lithium bis(trifluoromethane)sulfonimide, as a salt on an amorphous silicon anode, and compares the electrochemical response and SEI formation to its fluorinated version, bis(2,2,2-trifluoroethoxy) ethane (BTFEOE), by summore » frequency generation (SFG) vibrational spectroscopy under reaction conditions. The SFG results suggest that the —CF 3 end-groups of the linear ether BTFEOE change their adsorption orientation on the a-Si surface at OCP, leading to a better protective layer. Finally, supporting evidence from ex situ scanning electron microscopy and X-ray photoelectron spectroscopy depth profiling measurements shows that the fluorinated ether, BTFEOE, yields a smooth SEI on the a-Si surface and enables lithium ions to intercalate deeper into the a-Si bulk.« less

Characterization of partially hydrolyzed OCP crystals deposited in a gelatin matrix as a scaffold for bone tissue engineering

NASA Astrophysics Data System (ADS)

Ezoe, Yushi; Anada, Takahisa; Yamazaki, Hajime; Handa, Takuto; Kobayashi, Kazuhito; Takahashi, Tetsu; Suzuki, Osamu

2015-03-01

The present study was designed to investigate how hydrolysis of octacalcium phosphate (OCP) into hydroxyapatite is affected by the presence of gelatin (Gel) molecules and how osteoblastic cells respond to the resultant OCP hydrolyzate/Gel composites as the hydrolysis advances. OCP was prepared from a solution containing calcium and phosphate ions and Gel molecules, having a composition to produce a 40 wt% OCP as a final co-precipitate as the OCP/Gel. The precipitate was further incubated up to 40 h to advance the hydrolysis of OCP. These precipitates were processed to mold OCP/Gel sponges through lyophilization and dehydrothermal treatment. Chemical analysis, X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, and selected area electron diffraction revealed that the hydrolysis of OCP/Gel composite in hot water advanced in a time-dependent manner and faster than hydrolysis of OCP alone. The effect of Gel on the OCP hydrolysis was further examined in the presence of distinct concentrations of Gel molecules in hot water, showing that the Gel enhanced the hydrolysis as the concentration increased. Proliferation and differentiation of mouse bone marrow stromal ST-2 cells on the hydrolyzed OCP/Gel composites were compatible with Gel sponge alone after 21 days of culture, suggesting that these composites could be a candidate as a scaffold in bone tissue engineering.

Molecular Mechanism of Photoactivation and Structural Location of the Cyanobacterial Orange Carotenoid Protein

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Hao; Liu, Haijun; Niedzwiedzki, Dariusz M.

The orange carotenoid protein (OCP) plays a photoprotective role in cyanobacterial photosynthesis similar to that of nonphotochemical quenching in higher plants. Under high-light conditions, the OCP binds to the phycobilisome (PBS) and reduces the extent of transfer of energy to the photosystems. The protective cycle starts from a light-induced activation of the OCP. Detailed information about the molecular mechanism of this process as well as the subsequent recruitment of the active OCP to the phycobilisome are not known. We report here our investigation on the OCP photoactivation from the cyanobacterium Synechocystis sp. PCC 6803 by using a combination of nativemore » electrospray mass spectrometry (MS) and protein cross-linking. We demonstrate that native MS can capture the OCP with its intact pigment and further reveal that the OCP undergoes a dimer-to-monomer transition upon light illumination. The reversion of the activated form of the OCP to the inactive, dark form was also observed by using native MS. Furthermore, in vitro reconstitution of the OCP and PBS allowed us to perform protein chemical cross-linking experiments. Liquid chromatography–MS/MS analysis identified cross-linking species between the OCP and the PBS core components. Our result indicates that the N-terminal domain of the OCP is closely involved in the association with a site formed by two allophycocyanin trimers in the basal cylinders of the phycobilisome core. This report improves our understanding of the activation mechanism of the OCP and the structural binding site of the OCP during the cyanobacterial nonphotochemical quenching process.« less

Comparison of using polyurethane foam passive samplers and tree bark samples from Western China to determine atmospheric organochlorine pesticide.

PubMed

Li, Qiuxu; Lu, Yao; Jin, Jun; Li, Guangyao; Li, Peng; He, Chang; Wang, Ying

2016-03-01

Polyurethane foam (PUF) passive samplers were deployed and tree bark samples were collected at 15 sites across western China in 2013, and the organochlorine pesticide (OCP) concentrations in the samples were determined. Dichlorodiphenyltrichloroethane and its degradation products (collectively called DDTs), hexachlorocyclohexanes (HCHs), and hexachlorobenzene (HCB) were the dominant OCPs in the PUF samples and tree bark samples. The mean DDTs, HCHs and HCB concentrations were 33, 22 and 18ng/sample in the PUF samples, and 428, 74, and 43ng/(g lipid weight (lw)) in the tree bark, respectively. The OCP concentrations in the air, calculated using PUF-air and tree-bark-air partitioning models, were of the same order of magnitude. Both sample types showed that relatively fresh inputs of DDT and HCHs to the environment have occurred in western China. Meanwhile, PUF passive samplers were compared with the use of tree bark samples as passive samplers. The OCP compositions in the PUF and tree bark samples were different. Only the relatively stable OCPs (such as HCB, β-HCH and p,p'-dichlorodiphenyldichloro-ethylene (DDE)) were consistent in the PUF and tree bark samples. Copyright © 2015. Published by Elsevier B.V.

The new norms of food waste at the curb: Evidence-based policy tools to address benefits and barriers.

PubMed

Geislar, Sally

2017-10-01

Cities around the world are under increasing political pressure to develop organics collection programs (OCP) to curb the flow of food waste into landfills, reduce the associated greenhouse gases, and generate compost or biogas. While OCPs tend to focus on infrastructure, they often overlook the linchpin role that household behavior change plays in the success of OCPs. The current research used a longitudinal field experiment (n=370) to test both the effectiveness of a new curbside OCP and new social innovations intended to stimulate pro-environmental changes in household behavior. The findings suggest greater participation levels occur by implementing both new supportive infrastructure (i.e., curbside carts and collection services), and innovations that target the social aspects of waste (i.e., communicating social norms of separation). The data also provide an opportunity to test new model for predicting the most efficacious behavior-change interventions based on population profiles. The results provide some support for the model; reducing barriers (i.e., curbside carts and collection) tends to help all population profiles, but norm communication increases participation more for the hypothesized profile than for other sub-groups. Copyright © 2017 Elsevier Ltd. All rights reserved.

Feasibility study of the use of a daily electronic mail reminder to improve oral contraceptive compliance.

PubMed

Fox, Michelle C; Creinin, Mitchell D; Murthy, Amitasrigowri S; Harwood, Bryna; Reid, Lynn M

2003-11-01

Women who ingest their oral contraceptive pill (OCP) as part of a daily routine are more likely use their OCPs correctly. This trial examines the feasibility of an electronic-mail (e-mail) reminder system to improve OCP compliance. An e-mail reminder was sent to 50 new OCP users daily for 3 months. Subjects sent an e-mail reply to confirm receipt. OCP compliance was recorded on diaries. Four subjects were discontinued for not checking their e-mail. Active participants missed a median of 18% of the e-mail reminders (range: 0-65%). A follow-up visit was scheduled after completion of three OCP cycles. Of the 40 subjects returning completed diaries, 50% missed no active pills at all and 20% missed at least one in each cycle. Most found the daily e-mail somewhat (65%) or very helpful (19%) for OCP compliance. Of those continuing OCPs, 64% wanted to continue receiving e-mail reminders at the completion of the study. Because inconsistent OCP use is a significant cause of unplanned conception, the use of e-mail to improve OCP compliance has the potential to decrease unintended pregnancies.

Assessment of teacher interruptions on learners during oral case presentations.

PubMed

Yang, Glen; Chin, Rachel

2007-06-01

Studies have only recently begun to investigate the effects of interruptions on physicians in the emergency department (ED). To determine the frequency and nature of interruptions by the training physician that occur when medical trainees do oral case presentations (OCPs) in the ED. This was an observational study. Learner OCPs to attending emergency physicians were observed in the ED of an urban Level 1 trauma center at a major teaching hospital. A single investigator followed attending physicians blinded to the study objective in a nonrandomized convenience sampling of all ED shifts, recording information regarding teacher interruptions during new patient presentations. Learners completed a brief questionnaire after each OCP. A total of 196 OCPs were observed. The mean (+/-SD) duration of OCPs was 3.30 (+/-1.85) minutes, and the mean (+/-SD) number of interruptions was 0.75 (+/-0.60) per minute and 2.49 (+/-1.95) per OCP. The number of interruptions (per OCP) and duration of OCP varied by learner level of training, with more experienced learners giving shorter presentations and being interrupted less often. Frequency (per minute) of interruptions did not vary by learner level. In 40.3% of OCPs, attending physicians interrupted to give an assessment and/or a plan before the learner had done so, but 8.3% of interrupted learners believed that teacher interruptions were "disruptive" to their OCP. Attending emergency physicians frequently interrupt learners during new patient OCPs, with the number of interruptions varying by learner level of training. Teacher interruptions appear to have minimal, if any, detrimental effect on the perceived effectiveness of OCPs as a learning experience.

Oral contraceptive use and female genital arousal: methodological considerations.

PubMed

Seal, Brooke N; Brotto, Lori A; Gorzalka, Boris B

2005-08-01

This study explored effects of oral contraceptive pill (OCP) use on physiological sexual arousal as measured by a vaginal photoplethysmograph. Sixteen women aged 18-29 viewed audiovisual neutral and erotic stimuli before and an average of 6 weeks following the onset of OCP use. Although subjective measures of sexual arousal, including perceptions of genital arousal, significantly increased in response to erotic stimuli both before and after OCP onset, physiological sexual arousal only increased before OCP use. A comparison of individual responses before and after OCP onset reveals a much higher degree of intrasubject variability after OCP onset. We discuss these findings as they relate to OCP use as a confounding methodological variable to consider in future investigations employing vaginal photoplethysmography.

Does the Oral Contraceptive Pill Increase Plasma Intercellular Adhesion Molecule-1, Monocyte Chemoattractant Protein-1, and Tumor Necrosis Factor-α Levels in Women with Polycystic Ovary Syndrome: A Pilot Study.

PubMed

Yousuf, Syed Douhath; Rashid, Fouzia; Mattoo, Tahira; Shekhar, Chander; Mudassar, Syed; Zargar, M Afzal; Ganie, Mohd Ashraf

2017-02-01

Polycystic ovary syndrome (PCOS), the most common endocrinopathy of women, is a state of chronic low-grade inflammation and is closely linked to type 2 diabetes mellitus and cardiovascular disease. Oral contraceptive pills (OCPs), is the usual first choice of treatment in women with PCOS. Because OCP use has been linked to the risk of venous thrombosis and there are limited data on the effect of OCP use on the inflammatory state of women with PCOS, our objective was to compare the levels of intercellular adhesion molecule (ICAM)-1, tumor necrosis factor (TNF)-α, and monocyte chemoattractant protein (MCP)-1 between drug-naive and OCP-treated women with PCOS. DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: Consequent to women diagnosed with PCOS on the basis of Rotterdam 2003 criteria, either treated with OCPs (ethinylestradiol 0.03 mg, levonogestrel-0.15 mg) for a period of 6 months (n = 50) or drug-naive (n = 51) were enrolled in this cross-sectional study. The mean ages of patients and control participants were comparable (21.99 ± 4.78 vs 21.92 ± 5.83 years; P = .947) as was body mass index (24.47 ± 3.92 vs 23.66 ± 3.43; P = .271). Clinical and androgen excess symptoms were significantly better in the OCP group compared with the drug-naive group (P = .01, P = .04). Total cholesterol and low-density lipoprotein cholesterol levels were significantly higher in the OCP group (P = .01). Plasma ICAM-1 levels, TNF-α levels, and MCP-1 levels showed a higher trend in patients but reached statistical significance only in cases of ICAM-1 and TNF-α (P = .01). OCP treatment of 6 months increases plasma ICAM-1, MCP-1, and TNF-α levels among women with PCOS, although OCPs significantly help in ameliorating features of hyperandrogenism and regularizing menstrual cycles. These cytokines correlate positively with many metabolic parameters including plasma glucose, lipids, and homeostatic model assessment-insulin resistance. Further investigation with well designed, randomized, longitudinal studies might help to ascertain the effect of OCPs on proinflammatory profiles among women with PCOS. Copyright © 2016 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

The Unique Protein-to-Protein Carotenoid Transfer Mechanism.

PubMed

Maksimov, Eugene G; Sluchanko, Nikolai N; Slonimskiy, Yury B; Mironov, Kirill S; Klementiev, Konstantin E; Moldenhauer, Marcus; Friedrich, Thomas; Los, Dmitry A; Paschenko, Vladimir Z; Rubin, Andrew B

2017-07-25

Orange Carotenoid Protein (OCP) is known as an effector and regulator of cyanobacterial photoprotection. This 35 kDa water-soluble protein provides specific environment for blue-green light absorbing keto-carotenoids, which excitation causes dramatic but fully reversible rearrangements of the OCP structure, including carotenoid translocation and separation of C- and N-terminal domains upon transition from the basic orange to photoactivated red OCP form. Although recent studies greatly improved our understanding of the OCP photocycle and interaction with phycobilisomes and the fluorescence recovery protein, the mechanism of OCP assembly remains unclear. Apparently, this process requires targeted delivery and incorporation of a highly hydrophobic carotenoid molecule into the water-soluble apoprotein of OCP. Recently, we introduced, to our knowledge, a novel carotenoid carrier protein, COCP, which consists of dimerized C-domain(s) of OCP and can combine with the isolated N-domain to form transient OCP-like species. Here, we demonstrate that in vitro COCP efficiently transfers otherwise tightly bound carotenoid to the full-length OCP apoprotein, resulting in formation of photoactive OCP from completely photoinactive species. We accurately analyze the peculiarities of this process that, to the best of our knowledge, appears unique, a previously uncharacterized protein-to-protein carotenoid transfer mechanism. We hypothesize that a similar OCP assembly can occur in vivo, substantiating specific roles of the COCP carotenoid carrier in cyanobacterial photoprotection. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Effect of 12-month treatment with metformin and/or oral contraceptives on health-related quality of life in polycystic ovary syndrome.

PubMed

Altinok, Magda Lambaa; Ravn, Pernille; Andersen, Marianne; Glintborg, Dorte

2018-04-16

Health-related quality of life (HRQoL) is impaired in polycystic ovary syndrome (PCOS), but the effect of treatment with metformin (M) and/or oral contraceptives (OCP) is undetermined. To assess changes in HRQoL during 12-month randomized treatment with M, OCP or M + OCP in PCOS. Ninety women with PCOS were randomized to treatment with M, OCP or M + OCP. HRQoL was evaluated by a PCOS-specific visual analog scale (PCOS-VAS) regarding 1: Facial hair, 2: Body hair, 3: Acne, 4: Irregular menses, 5: Weight and 6: PCOS in general, and Short Form 36 (SF-36). PCOS-VAS1(facial hair) improved during treatment with OCP (n = 23) compared to M (n = 19), and during M + OCP (n = 23) compared to M treatment, whereas changes in PCOS-VAS2-6 and SF-36 scores were comparable between the three medical intervention groups. Pooled data (n = 65) showed improved PCOS-VAS scores during treatment (all p < .05), but changes in PCOS-VAS were unassociated with changes in BMI or FG-scores despite significant weight-loss during treatment with M (-3.0 kg (-10.3; 0.6)) and M + OCP (-1.9 kg (-4.9; 0.1)) and decreased FG-score during M + OCP treatment (median (quartiles)). PCOS-VAS scores improved significantly and to the same extent during treatment with M, OCP or M + OCP.

Modelling, analysis and validation of microwave techniques for the characterisation of metallic nanoparticles

NASA Astrophysics Data System (ADS)

Sulaimalebbe, Aslam

In the last decade, the study of nanoparticle (NP) systems has become a large and interesting research area due to their novel properties and functionalities, which are different from those of the bulk materials, and also their potential applications in different fields. It is vital to understand the behaviour and properties of nano-materials aiming at implementing nanotechnology, controlling their behaviour and designing new material systems with superior performance. Physical characterisation of NPs falls into two main categories, property and structure analysis, where the properties of the NPs cannot be studied without the knowledge of size and structure. The direct measurement of the electrical properties of metal NPs presents a key challenge and necessitates the use of innovative experimental techniques. There have been numerous reports of two/four point resistance measurements of NPs films and also electrical conductivity of NPs films using the interdigitated microarray (IDA) electrode. However, using microwave techniques such as open ended coaxial probe (OCP) and microwave dielectric resonator (DR) for electrical characterisation of metallic NPs are much more accurate and effective compared to other traditional techniques. This is because they are inexpensive, convenient, non-destructive, contactless, hazardless (i.e. at low power) and require no special sample preparation. This research is the first attempt to determine the microwave properties of Pt and Au NP films, which were appealing materials for nano-scale electronics, using the aforementioned microwave techniques. The ease of synthesis, relatively cheap, unique catalytic activities and control over the size and the shape were the main considerations in choosing Pt and Au NPs for the present study. The initial phase of this research was to implement and validate the aperture admittance model for the OCP measurement through experiments and 3D full wave simulation using the commercially available Ansoft High Frequency Structure Simulator (HFSS), followed by the electrical characterisation of synthesised Pt NP films using the novel miniature fabricated OCP technique. The results obtained from this technique provided the inspiration to synthesise and evaluate the microwave properties of Au NPs. The findings from this technique provided the motivation to characterise both the Pt and Au NP films using the DR technique. Unlike the OCP technique, the DR method is highly sensitive but the achievable measurement accuracy is limited since this technique does not have broadband frequency capability like the OCP method. The results obtained from the DR technique show a good agreement with the theoretical prediction. In the last phase of this research, a further validation of the aperture admittance models on different types OCP (i.e. RG-405 and RG-402 cables and SMA connector) have been carried out on the developed 3D full wave models using HFSS software, followed by the development of universal models for the aforementioned OCPs based on the same 3D full wave models.

Macrophage migration inhibitory factor (MIF) supports homing of osteoclast precursors to peripheral osteolytic lesions

PubMed Central

Movila, Alexandru; Ishii, Takenobu; Albassam, Abdullah; Wisitrasameewong, Wichaya; Howait, Mohammed; Yamaguchi, Tsuguno; Ruiz-Torruella, Montserrat; Bahammam, Laila; Nishimura, Kazuaki; Van Dyke, Thomas; Kawai, Toshihisa

2016-01-01

By binding to its chemokine receptor CXCR4 on osteoclast precursor cells (OCPs), it is well known that SDF-1 promotes the chemotactic recruitment of circulating OCPs to the homeostatic bone remodeling site. However, the engagement of circulating OCPs in pathogenic bone resorption remains to be elucidated. The present study investigated a possible chemoattractant role of MIF, another ligand for CXCR4, in the recruitment of circulating OCPs to the bone lytic lesion. To accomplish this, we used Csf1r-eGFP-KI mice to establish an animal model of Polymethyl methacrylate (PMMA) particle-induced calvarial osteolysis. In the circulating Csf1r-eGFP+ cells of healthy Csf1r-eGFP-KI mice, Csf1r+/CD11b+ cells showed a greater degree of RANKL-induced osteoclastogenesis compared to a subset of Csf1r+/RANK+ cells in vitro. Therefore, Csf1r-eGFP+/CD11b+ cells were targeted as functionally relevant OCPs in the present study. While expression of the two cognate receptors for MIF, CXCR2 and CXCR4, was elevated on Csf1r+/CD11b+ cells, transmigration of OCPs toward recombinant MIF in vitro was facilitated by ligation with CXCR4, but not CXCR2. Meanwhile, the level of PMMA-induced bone resorption in calvaria was markedly greater in wild-type mice compared to that detected in MIF-KO mice. Interestingly, in contrast to the elevated MIF, diminished SDF-1 was detected in a particle-induced bone lytic lesion of wild-type mice in conjunction with an increased number of infiltrating CXCR4+ OCPs. However, such diminished SDF-1 was not found in the PMMA-injected calvaria of MIF-KO mice. Furthermore, stimulation of osteoblasts with MIF in vitro suppressed their production of SDF-1, suggesting that MIF can down-modulate SDF-1 production in bone tissue. Systemically administered anti-MIF neutralizing mAb inhibited the homing of CXCR4+ OCPs, as well as bone resorption, in the PMMA-injected calvaria, while increasing locally produced SDF-1. Collectively, these data suggest that locally produced MIF in the inflammatory bone lytic site is engaged in the chemoattraction of circulating CXCR4+ OCPs. PMID:27082509

Organochlorine pesticide residues in surface water from Sichuan Basin to Aba Prefecture profile, east of the Tibetan Plateau

NASA Astrophysics Data System (ADS)

Liu, Hongxia; Hu, Ying; Qi, Shihua; Xing, Xinli; Zhang, Yuan; Yang, Dan; Qu, Chengkai

2015-06-01

Organochlorine pesticides (OCPs) found in rivers from the Sichuan Basin to Aba Prefecture profile were analyzed to assess possible health risks to adults and children who use the river as a source of drinking water. OCP concentrations in surface water ranged between 22.29-274.28 ng·L-1. Compared with other published data around the world, OCP levels in this study were moderate. Among all OCPs, hexachlorobenzene (HCB) and hexachlorocyclohexanes (HCHs) were the predominant compounds. Higher concentrations of OCPs were attributed close to the agricultural fields of the Sichuan Basin, current OCPs inputs, and long-range atmospheric transport from abroad. Various spatial patterns of OCPs in the profile might be affected by the usage and physicochemical properties of the pesticides, in addition to the adjacent geographical environment. The health risk assessment indicated that most OCPs had little impact on human health according to the acceptable risk level for carcinogens (10-6) recommended by the US EPA. However, carcinogenic effects caused by heptachlor, Aldrin, HCB, and α-HCH might occur in drinking water. The risk of negative impacts caused by OCPs is much higher for children than for adults.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garcia, Natalie K.; Guttman, Miklos; Ebner, Jamie L.

Influenza hemagglutinin (HA) mediates virus attachment to host cells and fusion of the viral and endosomal membranes during entry. While high-resolution structures are available for the pre-fusion HA ectodomain and the post-fusion HA2 subunit, the sequence of conformational changes during HA activation has eluded structural characterization. In this paper, we apply hydrogen-deuterium exchange with mass spectrometry to examine changes in structural dynamics of the HA ectodomain at various stages of activation, and compare the soluble ectodomain with intact HA on virions. At pH conditions approaching activation (pH 6.0–5.5) HA exhibits increased dynamics at the fusion peptide and neighboring regions, whilemore » the interface between receptor binding subunits (HA1) becomes stabilized. In contrast to many activation models, these data suggest that HA responds to endosomal acidification by releasing the fusion peptide prior to HA1 uncaging and the spring-loaded refolding of HA2. Finally, this staged process may facilitate efficient HA-mediated fusion.« less

Dynamic changes during acid-induced activation of influenza hemagglutinin

DOE PAGES

Garcia, Natalie K.; Guttman, Miklos; Ebner, Jamie L.; ...

2015-03-12

Influenza hemagglutinin (HA) mediates virus attachment to host cells and fusion of the viral and endosomal membranes during entry. While high-resolution structures are available for the pre-fusion HA ectodomain and the post-fusion HA2 subunit, the sequence of conformational changes during HA activation has eluded structural characterization. In this paper, we apply hydrogen-deuterium exchange with mass spectrometry to examine changes in structural dynamics of the HA ectodomain at various stages of activation, and compare the soluble ectodomain with intact HA on virions. At pH conditions approaching activation (pH 6.0–5.5) HA exhibits increased dynamics at the fusion peptide and neighboring regions, whilemore » the interface between receptor binding subunits (HA1) becomes stabilized. In contrast to many activation models, these data suggest that HA responds to endosomal acidification by releasing the fusion peptide prior to HA1 uncaging and the spring-loaded refolding of HA2. Finally, this staged process may facilitate efficient HA-mediated fusion.« less

Engineering the bone-ligament interface using polyethylene glycol diacrylate incorporated with hydroxyapatite.

PubMed

Paxton, Jennifer Z; Donnelly, Kenneth; Keatch, Robert P; Baar, Keith

2009-06-01

Ligaments and tendons have previously been tissue engineered. However, without the bone attachment, implantation of a tissue-engineered ligament would require it to be sutured to the remnant of the injured native tissue. Due to slow repair and remodeling, this would result in a chronically weak tissue that may never return to preinjury function. In contrast, orthopaedic autograft reconstruction of the ligament often uses a bone-to-bone technique for optimal repair. Since bone-to-bone repairs heal better than other methods, implantation of an artificial ligament should also occur from bone-to-bone. The aim of this study was to investigate the use of a poly(ethylene glycol) diacrylate (PEGDA) hydrogel incorporated with hydroxyapatite (HA) and the cell-adhesion peptide RGD (Arg-Gly-Asp) as a material for creating an in vitro tissue interface to engineer intact ligaments (i.e., bone-ligament-bone). Incorporation of HA into PEG hydrogels reduced the swelling ratio but increased mechanical strength and stiffness of the hydrogels. Further, HA addition increased the capacity for cell growth and interface formation. RGD incorporation increased the swelling ratio but decreased mechanical strength and stiffness of the material. Optimum levels of cell attachment were met using a combination of both HA and RGD, but this material had no better mechanical properties than PEG alone. Although adherence of the hydrogels containing HA was achieved, failure occurs at about 4 days with 5% HA. Increasing the proportion of HA improved interface formation; however, with high levels of HA, the PEG HA composite became brittle. This data suggests that HA, by itself or with other materials, might be well suited for engineering the ligament-bone interface.

Performance evaluation of a liquid tin anode solid oxide fuel cell operating under hydrogen, argon and coal

NASA Astrophysics Data System (ADS)

Khurana, Sanchit; LaBarbera, Mark; Fedkin, Mark V.; Lvov, Serguei N.; Abernathy, Harry; Gerdes, Kirk

2015-01-01

A liquid tin anode solid oxide fuel cell is constructed and investigated under different operating conditions. Electrochemical Impedance Spectroscopy (EIS) is used to reflect the effect of fuel feed as the EIS spectra changes significantly on switching the fuel from argon to hydrogen. A cathode symmetric cell is used to separate the impedance from the two electrodes, and the results indicate that a major contribution to the charge-transfer and mass-transfer impedance arises from the anode. The OCP of 0.841 V for the cell operating under argon as a metal-air battery indicates the formation of a SnO2 layer at the electrolyte/anode interface. The increase in the OCP to 1.1 V for the hydrogen fueled cell shows that H2 reduces the SnO2 film effectively. The effective diffusion coefficients are calculated using the Warburg element in the equivalent circuit model for the experimental EIS data, and the values of 1.9 10-3 cm2 s-1 at 700 °C, 2.3 10-3 cm2 s-1 at 800 °C and 3.5 10-3 cm2 s-1 at 900 °C indicate the system was influenced by diffusion of hydrogen in the system. Further, the performance degradation over time is attributed to the irreversible conversion of Sn to SnO2 resulting from galvanic polarization.

A modified cementing technique using BoneSource to augment fixation of the acetabulum in a sheep model.

PubMed

Timperley, A John; Nusem, Iulian; Wilson, Kathy; Whitehouse, Sarah L; Buma, Pieter; Crawford, Ross W

2010-08-01

Our aim was to assess in an animal model whether the use of HA paste at the cement-bone interface in the acetabulum improves fixation. We examined, in sheep, the effect of interposing a layer of hydroxyapatite cement around the periphery of a polyethylene socket prior to fixing it using polymethylmethacrylate (PMMA). We performed a randomized study involving 22 sheep that had BoneSource hydroxyapatite material applied to the surface of the acetabulum before cementing a polyethylene cup at arthroplasty. We studied the gross radiographic appearance of the implant-bone interface and the histological appearance at the interface. There were more radiolucencies evident in the control group. Histologically, only sheep randomized into the BoneSource group exhibited a fully osseointegrated interface. Use of the hydroxyapatite material did not give any detrimental effects. In some cases, the material appeared to have been fully resorbed. When the material was evident in histological sections, it was incorporated into an osseointegrated interface. There was no giant cell reaction present. There was no evidence of migration of BoneSource to the articulation. The application of HA material prior to cementation of a socket produced an improved interface. The technique may be useful in humans, to extend the longevity of the cemented implant by protecting the socket interface from the effect of hydrodynamic fluid flow and particulate debris.

Sex hormones and systemic inflammation are modulators of the obese-asthma phenotype.

PubMed

Scott, H A; Gibson, P G; Garg, M L; Upham, J W; Wood, L G

2016-07-01

Both systemic inflammation and sex hormones have been proposed as potential mediators of the obese-asthma phenotype. The aim of this study was to examine the associations between sex hormones, oral contraceptive pill (OCP) use, systemic inflammation and airway inflammation in adults with asthma. Obese (n = 39) and nonobese (n = 42) females and obese (n = 24) and nonobese (n = 25) males with asthma were recruited. Females were further categorized as reproductive-aged (<50 years old; n = 36) or older (>50 years old; n = 45). Thirteen (36.1%) reproductive-aged females were using the OCP. Participants had induced sputum cell counts measured and blood analysed for sex hormones and inflammatory markers. Obese reproductive-aged females had higher sputum %neutrophils than nonobese reproductive-aged females (45.4 ± 24.3% vs 27.5 ± 17.5%, P = 0.016); however, there was no difference in sputum neutrophils in obese compared with nonobese males (P = 0.620) or older females (P = 0.087). Multiple linear regression analysis found testosterone and OCP use to be negative predictors of sputum %neutrophils, while C-reactive protein and IL-6 were positive predictors of sputum %neutrophils. BMI and age were not significant predictors in the multivariate model. Reproductive-aged females using the OCP had significantly lower sputum %neutrophils than those not using the OCP (23.2 ± 12.6% vs 42.1 ± 23.8%, P = 0.015). This study suggests that sex hormones and systemic inflammation may be mediating the obese-asthma phenotype. The observation that OCP use was associated with lower sputum %neutrophils in reproductive-aged females warrants further investigation. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Occurrence and air-soil exchange of organochlorine pesticides and polychlorinated biphenyls at a CAWNET background site in central China: Implications for influencing factors and fate.

PubMed

Zhan, Lingxi; Lin, Tian; Wang, Zuwu; Cheng, Zhineng; Zhang, Gan; Lyu, Xiaopu; Cheng, Hairong

2017-11-01

Ambient air and soil samples were collected between March 2012 and March 2013 at Jinsha, a regional background site in central China, to measure the concentrations of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). The average concentrations of total OCPs and total PCBs were 191 ± 107 and 39.4 ± 27.1 pg/m 3 in air (gaseous and particulate phase) and 0.585 ± 0.437 and 0.083 ± 0.039 ng/g in soil, respectively. The higher concentrations of p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT) and p,p'-DDT/p,p'-DDE ratios in the soil indicated recent p,p'-DDT input to the soil. A strong positive temperature dependence and average fugacity fraction value > 0.5 were observed for p,p'-DDT, suggesting that volatilization of residual DDT in the soil was the main influencing factor on atmospheric p,p'-DDT. Highly average fugacity fractions (>0.7) of trans-chlordane (TC) and cis-chlordane (CC) and high TC/CC ratios both in the soil and atmosphere suggested fresh inputs. Higher gaseous concentrations of hexachlorobenzene (HCB) were observed in winter and negative temperature dependence was directly attributed to the surrounding ongoing source (e.g. fuel consuming activities), especially in winter. Overall, most targeted OCPs and PCBs were influenced by long-range transport, and fugacity fraction values indicated highly volatile compounds (e.g. α-hexachlorocyclohexane (α-HCH) and lower chlorinated PCBs) were volatilized and low volatility compounds (e.g. p,p'-DDE and higher chlorinated PCBs) were deposited at the air-soil interface. Knowing the source and sink of OCPs and PCBs can help to control their pollution in this area and provide a reference for other studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

Excited State Properties of 3'-Hydroxyechinenone in Solvents and in the Orange Carotenoid Protein from Synechocystis sp. PCC 6803

DOE Office of Scientific and Technical Information (OSTI.GOV)

Niedzwiedzki, Dariusz M.; Liu, Haijun; Blankenship, Robert E.

The orange carotenoid protein (OCP) is a 35 kDa water-soluble protein involved in a photoprotective mechanism of the photosynthetic apparatus of cyanobacteria. The OCP contains a single molecule of the carotenoid 3'-hydroxyechinenone (3'-hECN). We have performed transient absorption studies at 77 K in the visible and near-infrared spectral ranges on 3'-hECN in solvent glass and in both inactive (orange) and active (red) forms of OCP. In the OCP the cryogenic temperature prohibited the protein from spontaneous conversion between activity stages and allowed us to study well-defined spectral forms of the protein. The studies show that each form of the OCPmore » consists of two protein subpopulations having different photophysical properties of the bound 3'-hECN. At 77 K the inactive OCP reveals two lifetimes of the first excited state of 3'-hECN of 5.2 and 11 ps while in the active form of OCP these are 3.2 and 7.1 ps. We have also determined the energy of the first excited singlet state of 3'-hECN in long-lived subpopulations of both OCP forms at 77 K. This is 13,750 cm –1 in the inactive OCP and 12,300 cm -1 in the active OCP. Shortening of the lifetime and decrease of the energy of the first excited singlet state of 3'-hECN confirm the lengthening of the effective conjugation of the carotenoid upon the inactive-to-active conversion of OCP.« less

Organochlorine pesticide residues in dried cocoa beans obtained from cocoa stores at Ondo and Ile-Ife, Southwestern Nigeria.

PubMed

Oyekunle, J A O; Akindolani, O A; Sosan, M B; Adekunle, A S

2017-01-01

Levels of organochlorine pesticides (OCPs) were determined in dried cocoa beans obtained from cocoa produce stores at Ondo and Ile-Ife, Southwestern Nigeria. Cocoa beans samples were sun dried to a constant weight, pulverized and soxhlet extracted with dichloromethane to obtain the OCPs. Qualitative identification and quantitative evaluation of the extracted OCPs after clean-up on silica gel were accomplished with the aid of a Gas Chromatography coupled with an Electron Capture Detector (GC-ECD). Levels of OCPs in cocoa beans from Ondo had a mean range of ND (p, p'-DDE) to 82.17 ± 54.53 ng/g (p, p'-DDT) were higher than the OCPs levels in cocoa beans from Ile-Ife with a mean range of 0.37 ± 0.63 ng/g (Endrin) to 57.76 ± 81.48 ng/g (p, p'-DDT). The higher levels of OCPs detected in the cocoa beans from Ondo could be an indication of higher volume of OCPs application by cocoa farmers in Ondo and its environs since cocoa plantations were more concentrated than Ile-Ife environs. Levels of OCPs determined in the cocoa beans were within the Maximum Residue Limit (MRLs) for OCPs set by the World Health Organization/Food and Agricultural Organization. The study established the presence of OCPs in an important crop of Nigeria. Hence, there is the need to keep monitoring ecotoxicological chemical substances in agricultural food products of Nigeria so as to take steps that ensure health safety of end users.

Adiponectin, interleukin-6, monocyte chemoattractant protein-1, and regional fat mass during 12-month randomized treatment with metformin and/or oral contraceptives in polycystic ovary syndrome.

PubMed

Glintborg, Dorte; Mumm, Hanne; Altinok, Magda Lambaa; Richelsen, Bjørn; Bruun, Jens Meldgaard; Andersen, Marianne

2014-08-01

Central obesity in polycystic ovary syndrome (PCOS) is associated with increased inflammatory markers and increased risk for type 2 diabetes. To evaluate if improved body composition during treatment with metformin (M) vs. oral contraceptive pills (OCP) was associated with changes in circulating adiponectin, interleukin (IL)-6, and monocyte chemoattractant protein (MCP)-1. Ninety patients with PCOS were randomized to 12-month treatment with M (2 g/day), M + OCP (150 mg desogestrel + 30 microgram ethinylestradiol) or OCP. Adiponectin, IL-6, MCP-1, whole body DXA scans, and clinical evaluations were performed before and after the intervention period in the 65 study completers. Changes in inflammatory markers and changes in total and regional fat mass estimates. Adiponectin, IL-6, and MCP-1 levels were unchanged during the three types of medical intervention. Treatment with M and M + OCP was superior to OCP regarding decreased regional fat mass. Baseline adiponectin and IL-6 were associated with BMI, waist, and trunk fat mass. Changes in trunk fat were significantly associated with changes in IL-6 and MCP-1 during M + OCP. Long-term treatment with M alone or in combination with OCP was associated with improved body composition compared to OCP, whereas inflammatory markers were unchanged. OCP was not associated with increased inflammatory markers despite a small but significant weight gain.

Effects of inorganic ions on morphology of octacalcium phosphate grown on cation selective membrane at physiological temperature and pH in relation to enamel formation

NASA Astrophysics Data System (ADS)

Iijima, Mayumi; Moriwaki, Yutaka

1989-05-01

The crystal growth of octacalcium phosphate (OCP) is of particular interest, since there is a possibility that OCP is formed in the early stage of tooth enamel formation. In this study, the effects of CO2-3, Mg2+ and F-ions on the morphology of OCP were investigated in a membrane system, where a cation selective membrane was used to simulate amelogenesis. Reactions were carried out at pH 6.3, 6.5 and 6.8 for 3 days at 37°C. In most cases, these ions suppressed the crystal growth in the c-axis direction of OCP, particularly when they coexisted. The morphology of OCP crystal changed from ribbon-like to flake-like, depending on the inhibitory activity. The inhibitory activity, particularly that of F - ion, was suppressed at pH lower than pH 6.8. Antagonistic effect of Mg2+ and F-ion was observed at pH 6.5. In the case of F - ion, OCP crystals showed a unique pattern, which suggests hydrolysis of OCP and subsequent growth of apatite. These findings indicate that inorganic ions, particularly F - ion, influence the growth of OCP. Although CO2-3, Mg2+andF-ions coexisted, extended growth in the c-axis direction of OCP took place at pH 6.0.

Successive and cyclic oral contraceptive pill pretreatment improves IVF/ICSI outcomes of PCOS patients and ameliorates hyperandrogenism and antral follicle excess.

PubMed

Pan, Jie-Xue; Liu, Ye; Ke, Zhang-Hong; Zhou, Cheng-Liang; Meng, Qing; Ding, Guo-Lian; Xu, Gu-Feng; Sheng, Jian-Zhong; Huang, He-Feng

2015-04-01

To evaluate different oral contraceptive pill (OCP) pretreatment associated differential in-vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) outcomes of polycystic ovary syndrome (PCOS) patients and explore enhanced hormonal balance induced by the pretreatment. This retrospective study included 500 PCOS women and 565 normal ovulating counterparts undergoing IVF/ICSI. The PCOS patients were divided into three groups based on the OCP pretreatment regimens: non-OCP (without OCP pretreatment), unsuccessive OCP (the period of successive pretreatment ≤2 months) and successive OCP (the period of successive pretreatment ≥3 months) groups. Comprehensive hormonal and ultra-sonographic assessments were performed before/after IVF pretreatment. Confounding factors affecting pregnancy outcomes were analyzed with logistic regression. PCOS patients with significant endocrine disorders had reduced implantation and pregnancy rates and increased miscarriage rate. Successive, not unsuccessive OCP pretreatment, significantly improved the implantation and pregnancy rates, and reduced the incidence of monotocous small-for-gestational age infants, which was accompanied by remarkably decreased hyperandrogenism and antral follicles. PCOS is an independent risk factor for poor IVF outcome. Successive, not unsuccessive, OCP cyclical pretreatment could improve pregnancy outcome of PCOS patients, associated with reduction of hyperandrogenism and antral follicle excess.

Overdose of oral contraceptive pills as a means of intentional self-poisoning amongst young women in Sri Lanka: considerations for family planning.

PubMed

Weerasinghe, Manjula; Konradsen, Flemming; Eddleston, Michael; Pearson, Melissa; Agampodi, Thilini; Storm, Frederikke; Agampodi, Suneth

2017-04-01

Oral contraceptive pills (OCPs) are one of the most popular family planning methods in Sri Lanka. As part of two hospital-based studies on self-harm, the use of OCPs was identified, from yet unpublished results, as a means of intentional self-poisoning. To inform future guidelines for better OCP promotion, this article aims to describe the extent, patient characteristics and outcomes of OCP self-poisoning in the North Central Province of Sri Lanka. A secondary analysis was carried out on two hospital-based self-harm case series, from January 2011 to June 2014. Fifty-four patients (52 women and two men) with an overdose of OCP as a means of intentional self-poisoning were admitted to one of the surveyed hospitals. The median age of the patients was 19 (interquartile range, 5) years. None of the patients were severely sick from their overdose and two-thirds of the patients were discharged within a day of admission. Intentional self-poisoning with OCPs represented less than 5% of all types of intentional medicine self-poisonings recorded at the hospitals. Information available for a subset of female patients indicates that many cases (13/23, 56.5%) were in their first year of marriage. More research is required to understand why young women in rural Sri Lanka overdose with OCPs as a means of intentional self-poisoning. Although the toxicity of OCPs is low and the public health significance of OCP poisoning remains minor, reproductive health service providers should be attentive to OCP overdose, monitor the development of this problem, and ensure appropriate information to OCP users. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

The benefit-to-risk ratio of common treatments in PCOS: effect of oral contraceptives versus metformin on atherogenic markers.

PubMed

Christakou, Charikleia; Kollias, Anastasios; Piperi, Christina; Katsikis, Ilias; Panidis, Dimitrios; Diamanti-Kandarakis, Evanthia

2014-01-01

To compare the effects of oral contraceptives (OCPs) and metformin on atherogenic markers, including serum levels of advanced glycated end products (AGEs) and C-reactive protein (CRP), in lean women (Body Mass Index below 25 kg/m(2)) with polycystic ovary syndrome (PCOS), defined by NIH criteria. Prospective open-label study. One hundred and twenty women with PCOS were treated for 6 months with one of the following treatments: ethinylestradiol plus cyproterone acetate (OCP 1, n=40) or ethinylestradiol plus drospirenone (OCP2, n=40) or metformin (MET, n=40). The three groups were age and BMI-matched (mean age: 22 ± 0.56 yrs in group OCP1; 23.24 ± 0.64 yrs in group OCP2; 21.50 ± 0.53 yrs in group MET; mean BMI 21.80 ± 0.35 kg/m(2) in group OCP1; 22.37 ± 0.48 kg/m(2) in group OCP2; 23.03 ± 0.67 kg/m(2) in group MET). At 6 months serum AGEs were decreased in group OCP1 (P=0.005) and group MET (P=0.001), whereas these were marginally decreased in group OCP2 (P=0.069). Treatment with metformin was associated with a greater percent decrease of AGEs. CRP was decreased with metformin (P<0.001), but was increased with OCPs (P<0.001). This study evaluates common therapeutic options in women with PCOS by reconsidering and prioritizing the goals of treatment. OCPs and metformin appear to have differential effects on atherogenic molecules in lean PCOS patients, but metformin was superior in reducing serum AGEs and CRP. Clinicians should individualize the benefit-to-risk ratio of pharmaceutical intervention in women with PCOS in order to choose the formulation with the greatest overall efficacy as well as safety in terms of cardiovascular risk.

Brachial artery endothelial function is stable across a menstrual and oral contraceptive pill cycle, but lower in premenopausal women than age-matched men.

PubMed

Shenouda, Ninette; Priest, Stacey E; Rizzuto, Vanessa I; MacDonald, Maureen J

2018-05-04

Sex hormone concentrations differ between men, premenopausal women with natural menstrual cycles (NAT), and premenopausal women using oral contraceptive pills (OCP), as well as across menstrual or OCP phases. This study sought to investigate how differences in sex hormones, particularly estradiol, between men and women and across cycle phases, may influence brachial artery endothelial function. Fifty-three healthy adults (22{plus minus}3 yrs; 20 men, 15 NAT, 18 second, third or fourth generation OCP) underwent assessments of sex hormones and endothelial (flow-mediated dilation test, FMD) and smooth muscle (nitroglycerin test, NTG) function. Men were tested three times at one-week intervals, and women were tested three times throughout a single menstrual or OCP cycle (NAT: menstrual, mid-follicular, luteal; OCP: placebo/no pill, 'early' and 'late' active pill). Endogenous estradiol concentration was comparable between men and women in their NAT menstrual or OCP placebo phase (p=0.36) but increased throughout a NAT cycle (p<0.001). Allometrically scaled FMD did not change across a NAT or OCP cycle but was lower in both groups of women than men (p=0.005), whereas scaled NTG was lower only in NAT women (p=0.001). Changes in estradiol across a NAT cycle were not associated with changes in relative FMD (r2=0.01, p=0.62) or NTG (r2=0.09, p=0.13). Duration of OCP use was negatively associated with the average relative FMD for second generation OCP users only (r=-0.65, p=0.04). Our findings suggest that brachial endothelial function is unaffected by cyclic hormonal changes in premenopausal women but may be negatively impacted by longer term use of second generation OCPs.

[Distribution characteristics of organochlorine pesticides in soil from Daiyun Mountain Range in Fujian, China].

PubMed

Qu, Cheng-Kai; Qi, Shi-Hua; Zhang, Li; Huang, Huan-Fang; Zhang, Jia-Quan; Zhang, Yuan; Yang, Dan; Liu, Hong-Xia; Chen, Wei

2013-11-01

Totally 101 typical surface soil samples were collected from Daiyun Mountain Range, and 20 compounds of OCPs were analyzed by a Ni electron capture detector (GC-ECD) to investigate the horizontal distribution and composition of organochlorine pesticides (OCPs) in the surface soil of Daiyun Mountain Range. The results showed that all OCPs were detected in the soil samples. The detection ratios of OCPs were all over 90%, except for Endrin and beta-HCH. The sum concentration of HCHs, DDTs, Endosulfan and Endosulfan sulfate, accounted for 79.51% of the total OCPs, which were considered to be the dominant OCPs in the Daiyun Mountain Range. The OCPs concentrations in the surface soils ranged from 2.56 to 465.99 ng x g(-1) with a mean value of 38.00 ng x g)(-1). Compared with other regions, the concentrations of HCHs and DDTs in this study stayed in a low pollution level. Endosulfan and Endosulfan sulfate showed a certain degree of risk in the surface soil of the study area. Source analysis showed that new input of lindane and dicofol might occur in the survey region. The historical application was the prime source of Endosulfan. The residue level of OCPs in different lands was in the following order: paddy land > vegetable land > orchard. The OCPs pollution of orchard soil was primarily due to the new input of lindane and dicofol, while the pollution of paddy land was mainly from the usage of Endosulfan.

Organochlorine pesticides (OCPs) in wetland soils under different land uses along a 100-year chronosequence of reclamation in a Chinese estuary

PubMed Central

Bai, Junhong; Lu, Qiongqiong; Zhao, Qingqing; Wang, Junjing; Gao, Zhaoqin; Zhang, Guangliang

2015-01-01

Soil profiles were collected at a depth of 30 cm in ditch wetlands (DWs), riverine wetlands (RiWs) and reclaimed wetlands (ReWs) along a 100-year chronosequence of reclamation in the Pearl River Delta. In total, 16 OCPs were measured to investigate the effects of wetland reclamation and reclamation history on OCP levels. Our results showed that average ∑DDTs, HCB, MXC, and ∑OCPs were higher in surface soils of DWs compared to RiWs and ReWs. Both D30 and D20 soils contained the highest ∑OCP levels, followed by D40 and D100 soils; lower ∑OCP levels occurred in D10 soils. Higher ∑OCP levels were observed in the younger RiWs than in the older ones, and surface soils exhibited higher ∑OCP concentrations in the older ReWs compared with younger ReWs. The predominant percentages of γ-HCH in ∑HCHs (>42%) and aldrin in ∑DRINs (>46%) in most samples reflected the recent use of lindane and aldrin. The presence of dominant DDT isomers (p,p’-DDE and p,p’-DDD) indicated the historical input of DDT and significant aerobic degradation of the compound. Generally, DW soils had a higher ecotoxicological risk of OCPs than RiW and ReW soils, and the top 30 cm soils had higher ecotoxicological risks of HCHs than of DDTs. PMID:26633149

Organochlorine pesticides (OCPs) in wetland soils under different land uses along a 100-year chronosequence of reclamation in a Chinese estuary

NASA Astrophysics Data System (ADS)

Bai, Junhong; Lu, Qiongqiong; Zhao, Qingqing; Wang, Junjing; Gao, Zhaoqin; Zhang, Guangliang

2015-12-01

Soil profiles were collected at a depth of 30 cm in ditch wetlands (DWs), riverine wetlands (RiWs) and reclaimed wetlands (ReWs) along a 100-year chronosequence of reclamation in the Pearl River Delta. In total, 16 OCPs were measured to investigate the effects of wetland reclamation and reclamation history on OCP levels. Our results showed that average ∑DDTs, HCB, MXC, and ∑OCPs were higher in surface soils of DWs compared to RiWs and ReWs. Both D30 and D20 soils contained the highest ∑OCP levels, followed by D40 and D100 soils; lower ∑OCP levels occurred in D10 soils. Higher ∑OCP levels were observed in the younger RiWs than in the older ones, and surface soils exhibited higher ∑OCP concentrations in the older ReWs compared with younger ReWs. The predominant percentages of γ-HCH in ∑HCHs (>42%) and aldrin in ∑DRINs (>46%) in most samples reflected the recent use of lindane and aldrin. The presence of dominant DDT isomers (p,p’-DDE and p,p’-DDD) indicated the historical input of DDT and significant aerobic degradation of the compound. Generally, DW soils had a higher ecotoxicological risk of OCPs than RiW and ReW soils, and the top 30 cm soils had higher ecotoxicological risks of HCHs than of DDTs.

Experience of public procurement of Open Compute servers

NASA Astrophysics Data System (ADS)

Bärring, Olof; Guerri, Marco; Bonfillou, Eric; Valsan, Liviu; Grigore, Alexandru; Dore, Vincent; Gentit, Alain; Clement, Benoît; Grossir, Anthony

2015-12-01

The Open Compute Project. OCP (http://www.opencompute.org/). was launched by Facebook in 2011 with the objective of building efficient computing infrastructures at the lowest possible cost. The technologies are released as open hardware. with the goal to develop servers and data centres following the model traditionally associated with open source software projects. In 2013 CERN acquired a few OCP servers in order to compare performance and power consumption with standard hardware. The conclusions were that there are sufficient savings to motivate an attempt to procure a large scale installation. One objective is to evaluate if the OCP market is sufficiently mature and broad enough to meet the constraints of a public procurement. This paper summarizes this procurement. which started in September 2014 and involved the Request for information (RFI) to qualify bidders and Request for Tender (RFT).

Influence of oral contraceptive pills on phenotype expression in women with polycystic ovary syndrome.

PubMed

Mulders, Annemarie G M; ten Kate-Booij, Marianne; Pal, Richard; De Kruif, Marjolijn; Nekrui, Lizka; Oostra, Ben A; Fauser, Bart C J M; Laven, Joop S E

2005-12-01

Polycystic ovarian syndrome (PCOS) is characterized by a heterogeneous phenotype including chronic anovulation, hyperandrogenism and polycystic ovaries. The use of oral contraceptive pills (OCP) alters features characteristic for the syndrome. In the present study, PCOS features were compared between women using or not using OCP at the time of the study. One hundred and one women diagnosed with normogonadotrophic anovulatory infertility were included. A total of 81 (80%) women were diagnosed with PCOS (revised 2003 criteria). From these women, a total of 54 did not use OCP, whereas 27 women did. Corrected for age, women taking OCP had increased serum concentrations of sex hormone-binding globulin (P < 0.001). Serum concentrations of testosterone (P = 0.04) and androstenedione (P = 0.01) were decreased. These differences resulted in a decreased free androgen index for women currently taking OCP compared with women without (P < 0.001). The mean ovarian volume/ovary and the mean follicle number/ovary were not different. Use of OCP influences phenotype expression (the observable trait) of individual women known to suffer from PCOS by reducing hyperandrogenism. Despite taking OCP, women still fulfilled the revised 2003 criteria for the syndrome, as PCO morphology was still present. Hence, OCP use does not appreciably affect the PCOS phenotype.

In Vivo and In Vitro Nitinol Corrosion Properties

NASA Astrophysics Data System (ADS)

Lonn, Melissa K.; Metcalf, Justin M.; Choules, Brian D.

2015-09-01

Regulatory authorities often require in vitro testing on medical devices prior to approval. Current standardized corrosion testing methods (ASTM F2129) require testing in a non-physiologic, de-oxygenated solution for a pre-exposure time of ≤1 h; however, no correlations between the prescribed simulated environment and whole blood conditions have been elucidated. This study compared open circuit potential (OCP), breakdown potentials (Eb), Eb - OCP, and cyclic polarization curves tested in vivo (OCP only) and in vitro in whole blood to those tested in phosphate-buffered saline (PBS). Two oxide thicknesses of Nitinol, two solution oxygen contents (deaerated and aerated solutions), and two pre-exposure durations (acute and chronic) were investigated. The in vitro OCP in whole blood was not significantly different than the in vivo OCP, suggesting that whole blood in vitro can be used to determine baseline corrosion behavior of medical implants. Eb - OCP tested per ASTM F2129 was comparable to acute whole blood and was conservative compared to chronic whole blood for both oxide thicknesses. However, OCP, Eb, and cyclic polarization curves were not always comparable to whole blood. Testing in aerated PBS achieved Eb, Eb - OCP, and cyclic polarization curves that were comparable to or more conservative than whole blood testing, regardless of pre-exposure duration and oxide thickness.

Cancers in Australia in 2010 attributable to and prevented by the use of combined oral contraceptives.

PubMed

Jordan, Susan J; Wilson, Louise F; Nagle, Christina M; Green, Adele C; Olsen, Catherine M; Bain, Christopher J; Pandeya, Nirmala; Whiteman, David C; Webb, Penelope M

2015-10-01

To estimate the proportion and number of cancers occurring in Australia in 2010 attributable to combined oral contraceptive pill (OCP) use. We estimated the population attributable fraction (PAF) for cancers causally associated with combined OCP use (breast, cervix), and the proportion of endometrial and ovarian cancers prevented (prevented fraction [PF]). We used standard formulae incorporating prevalence of combined OCP use in the Australian population, relative risks of cancer associated with this exposure and cancer incidence. An estimated 105 breast and 52 cervical cancers (0.7% and 6.4% of each cancer, respectively) in Australia in 2010 were attributable to current use of combined OCP. Past combined OCP use was estimated to have prevented 1,032 endometrial and 308 ovarian cancers in 2010, reducing the number of cancers that would otherwise have occurred by 31% and 19%, respectively. A small proportion of breast and cervical cancers is attributable to combined OCP use; OCP use is likely to have prevented larger numbers of endometrial and ovarian cancers. Women seeking contraceptive advice should be told of potential adverse effects, but should also be told that - along with reproductive health benefits - combined OCP use can reduce long-term risks of ovarian and endometrial cancers. © 2015 The Authors.

Influence of polarized PZT on the crystal growth of calcium phosphate

NASA Astrophysics Data System (ADS)

Sun, Xiaodan; Ma, Chunlai; Wang, Yude; Li, Hengde

2002-01-01

The effects of polarization on the crystallization of calcium phosphate are studied in this work. Crystals of calcium phosphate from saturated solution of hydroxyapatite (HA, Ca 10(PO 4) 6(OH) 2) were deposited on the surfaces of ferroelectric ceramics lead zirconate titanium (Pb(Ti,Zr)O 3, PZT). The results of the experiment demonstrated the acceleration effects of polarized PZT on the crystal growth of calcium phosphate. Furthermore, it is indicated that polarization also influenced the orientation of the deposited crystals due to the growth of a layer of (0 0 2) oriented octacalcium phosphate (OCP, Ca 8H 2(PO 4) 6·5H 2O) on the negatively charged surfaces of PZT.

Choosing the Right Oral Contraceptive Pill for Teens.

PubMed

Powell, Anne

2017-04-01

Oral contraceptive pills (OCPs) continue to be the most commonly used form of prescription contraceptives used by adolescents in the United States. With proper use, oral contraceptives provide safe and effective birth control. Broad categories of OCPs include progestin-only pills (POPs) and combined oral contraceptive pills (COCs). Certain types of progestins have more potent antiandrogenic properties and are more effective in treating acne, hirsutism, and polycystic ovary syndrome. This article reviews types of OCPs, discusses risks and benefits of OCPs, and provides guidance for how to choose the most beneficial and appropriate OCP for individual adolescent patients. Copyright © 2017 Elsevier Inc. All rights reserved.

Oral contraceptives in polycystic ovary syndrome: risk-benefit assessment.

PubMed

Yildiz, Bulent O

2008-01-01

Combined oral contraceptive pills (OCPs) have been a key component of the chronic treatment of polycystic ovary syndrome (PCOS) by improving androgen excess and regulating menstrual cycles. Earlier epidemiologic studies with second- and third-generation OCPs in the general population have raised important questions regarding long-term cardiometabolic effects of these agents. In PCOS, there are only a few short-term studies with contradictory results evaluating potential adverse effects of OCPs on cardiovascular risk factors and glucose homeostasis. These studies included a small number of participants and did not take into account several confounding factors that might influence the outcome. Nevertheless, limited available data support the benefits of long-term OCP use in PCOS. By contrast, solid evidence for cardiometabolic adverse outcome with the use of these agents, especially with newer OCPs containing antiandrogenic progestins, is lacking. More studies are needed to resolve controversies regarding the safety of long-term OCP use in PCOS. Meanwhile, assessment of each PCOS patient's personal cardiometabolic risk profile should be an essential component of the evaluation before prescribing OCPs and also during follow-up.

Contraception in Japan: Current trends.

PubMed

Yoshida, Honami; Sakamoto, Haruka; Leslie, Asuka; Takahashi, Osamu; Tsuboi, Satoshi; Kitamura, Kunio

2016-06-01

High proportion of Japanese uses condoms; lower proportion uses oral contraceptive pills (OCPs). We examined the longitudinal patterns for contraceptive usage in Japan and evaluated differences before and after OCP government approval. We accessed nationally representative survey data for women aged 16-49years from 1950 to 2014. Usage of condoms and OCP was 83.4% and 3.0%, respectively in 2014. OCP use before (1.21%) and after (1.97%) government approval did not differ significantly (p=.58). The prevalence of OCP usage remains low in Japan. A wide gap in use between Japan and other developed countries exists. Through a wide gap in OCP use between Japan and other countries, we revealed how choices of contraceptive methods and their benefits could be openly available for women of reproductive age, and how health care professionals disseminate appropriate knowledge about contraception for women in need. Copyright © 2016 Elsevier Inc. All rights reserved.

A simulation study of thinning and fuel treatments on a wildland-urban interface in eastern Oregon, USA

Treesearch

Alan A. Ager; Andrew J. McMahan; James J. Barrett; Charles W. McHugh

2007-01-01

We simulated long-term forest management activities on 16,000-ha wildland-urban interface in the Blue Mountains near La Grande, Oregon. The study area is targeted for thinning and fuels treatments on both private and Federally managed lands to address forest health and sustainability concerns and reduce the risk of severe wildfire. We modeled number of benchmark...

Contamination from organochlorine pesticides (OCPs) in agricultural soils of Kuttanad agroecosystem in India and related potential health risk.

PubMed

Sruthi, S N; Shyleshchandran, M S; Mathew, Sunil Paul; Ramasamy, E V

2017-01-01

The presence and distribution of a few organochlorine pesticides (OCPs) in the paddy fields of the Kuttanad agroecosystem (KAE) was examined in the present study. Kuttanad forms a part of the Vembanad wetland system which is a Ramsar site of international importance in the state of Kerala. This study, to the best of our knowledge, is the first report on the occurrence of OCP residues in KAE. Pesticide residue analysis was done with gas chromatograph (GC-ECD). Twenty-one soil samples were collected for the multiresidual analysis of OCPs. Sixteen OCP residues with a notable concentration were observed from the study area. α-BHC; β-BHC; γ-BHC; δ-BHC; α-chlordane; γ-chlordane; heptachlor; 4,4-DDT; 4,4-DDE; 4,4-DDD; α-endosulfan; β-endosulfan; aldrin; dieldrin; endrin aldehyde; and endrin ketone were the residues observed. The percentage-wise occurrence of OCP residues in the soil samples analysed (total of 63 samples from 21 sites, three samples per site) exhibits the following order: Σ BHC˃ Σ chlordane ˃ Σ dieldrin ˃ Σ aldrin ˃ Σ endrin˃ Σ heptachlor = endosulfan˃ Σ DDT. All pesticides detected from KAE are in the list of priority pollutants of US Environmental Protection Agency (USEPA). The distribution pattern of OCPs in the KAE soils revealed their origin as both historical and recent application of pesticides. Health risk assessment of OCP residues on human population was also conducted. The findings indicated that the concentrations of OCPs were within the permissible limits of USEPA, thus, the human population in the study area was safe.

Ultrasonication followed by single-drop microextraction combined with GC/MS for rapid determination of organochlorine pesticides from fish.

PubMed

Shrivas, Kamlesh; Wu, Hui-Fen

2008-02-01

A novel, rapid and simple sample pretreatment technique termed ultrasonication followed by single-drop micro-extraction (U-SDME) has been developed and combined with GC/MS for the determination of organochlorine pesticides (OCPs) in fish. In the present work, the lengthy procedures generally used in the conventional methods like, Soxhlet extraction, supercritical fluid extraction, pressurized liquid extraction and microwave assisted solvent extraction for extraction of OCPs from fish tissues are minimized by the use of two simple extraction procedures. Firstly, OCPs from fish were extracted in organic solvent with ultrasonication and then subsequently preconcentrated by single-drop micro-extraction (SDME). Extraction parameters of ultrasonication and SDME were optimized in spiked sample solution in order to obtain efficient extraction of OCPs from fish tissues. The calibration curves for OCPs were found to be linear between 10-1000 ng/g with correlation of estimations in the range 0.990-0.994. The recoveries obtained in blank fish tissues were ranged from 82.1 to 95.3%. The LOD and RSD for determination of OCPs in fish were 0.5 ng/g and 9.4-10.0%, respectively. The proposed method was applied for the determination of bioconcentration factor in fish after exposure to different concentrations of OCPs in cultured water. The present method avoids the co-extraction of lipids, long extraction steps (>12 h) and large amount of organic solvent for the separation of OCPs. The main advantages of the present method are rapid, selective, sensitive and low cost for the determination of OCPs in fish.

Interest in over-the-counter access to oral contraceptives among women in the United States.

PubMed

Grossman, Daniel; Grindlay, Kate; Li, Rick; Potter, Joseph E; Trussell, James; Blanchard, Kelly

2013-10-01

A growing body of evidence indicates that over-the-counter (OTC) access to oral contraceptive pills (OCPs) is safe and effective. We performed a nationally representative survey of adult women at risk of unintended pregnancy using a probability-based online panel. In November-December 2011, 2046 eligible women completed the survey. Weighted proportions were calculated, and logistic regression was used to identify covariates associated with support for and interest in using an OTC OCP. A total of 62.2% said they were strongly (31.4%) or somewhat (30.9%) in favor of OCPs being available OTC. A total of 37.1% of participants reported being likely to use OCPs if available OTC, including 58.7% of current users, 28.0% using no method and 32.7% using a less effective method. Covariates associated with a higher odds of reporting interest in using OTC OCPs were younger age; being divorced, being separated or living with a partner (versus married); being uninsured or having private insurance (versus public insurance); living in the south (versus northeast); and current use of OCPs or less effective methods, or nonuse of contraception (versus use of another hormonal method or intrauterine device). Among respondents who said they were likely to use OTC OCPs, the highest amount they were willing to pay was on average $20. US women are supportive of OTC access to OCPs, and many would obtain refills OTC or start using OCPs if they were available OTC. Copyright © 2013. Published by Elsevier Inc.

Contamination characteristics of organochlorine pesticides in multimatrix sampling of the Hanjiang River Basin, southeast China.

PubMed

Liu, Jia; Qi, Shihua; Yao, Jun; Yang, Dan; Xing, Xinli; Liu, Hongxia; Qu, Chengkai

2016-11-01

Hanjiang River, the second largest river in Guangdong Province, Southern China, is the primary source of drinking water for the cities of Chaozhou and Shantou. Our previous studies indicated that soils from an upstream catchment area of the Hanjiang River are moderately contaminated with organochlorine pesticides (OCPs), which can easily enter the river system via soil runoff. Therefore, OCPs, especially downstream drinking water sources, may pose harmful health and environmental risks. On the basis of this hypothesis, we measured the OCP concentrations in dissolved phase (DP), suspended particle matter (SPM), and surface sediment (SS) samples collected along the Hanjiang River Basin in Fujian and Guangdong provinces. OCP residue levels were quantified through electron capture detector gas chromatography to identify the OCP sources and deposits. The concentration ranges of OCPs in DP, SPM, and SS, respectively, were 2.11-12.04 (ng/L), 6.60-64.77 (ng/g), and 0.60-4.71 (ng/g) for hexachlorocyclohexanes (HCHs), and 2.49-4.77 (ng/L), 6.75-80.19 (ng/g), and 0.89-252.27 (ng/g) for dichloro-diphenyl-trichloroethanes (DDTs). Results revealed that DDTs represent an ecotoxicological risk to the Hanjiang River Basin, as indicated by international sediment guidelines. This study serves as a basis for the future management of OCP concentrations in the Hanjiang River Basin, and exemplifies a pattern of OCP movement (like OCP partition among multimedia) from upstream to downstream. This pattern may be observed in similar rivers in China. Copyright © 2016 Elsevier Ltd. All rights reserved.

The effects of Peltier marking on semiconductor growth in a magnetic field

NASA Astrophysics Data System (ADS)

Sellers, Cheryl Casper

This research represents a model for three dimensional semiconductor growth in a vertical Bridgman process within an externally applied magnetic field with the additional effects of Peltier marking. The magnetic field is strong enough that inertial effects can be neglected and that viscous effects are confined to boundary layers. The objective of this research is a first step in the development of a method to accurately predict the distribution of dopants and species in the melt after a current pulse with a given duration and strength, with a given magnetic field and with a given crystal-melt interface shape. The first model involves an asymptotic solution to provide physical clarification of the flow. In both models the crystal/melt interface is modeled as fr=3r2 where 3≪1 . The first model incorporates a variable, a which ranges from 0.25 to 1.0. The second model involves an analytical solution with an arbitrary Ha and a≪1 . These models show the how the azimuthal velocity varies with increasing Ha and how the stream function varies in the meridional problem. This gives insight into how the dopant is mixed during the crystal growth process. The results demonstrate that current pulses with relatively weak magnetic fields and modest interface curvature can lead to very strong mixing in the melt.

Process Parameters on the Crystallization and Morphology of Hydroxyapatite Powders Prepared by a Hydrolysis Method

NASA Astrophysics Data System (ADS)

Wang, Moo-Chin; Hon, Min-Hsiung; Chen, Hui-Ting; Yen, Feng-Lin; Hung, I.-Ming; Ko, Horng-Huey; Shih, Wei-Jen

2013-07-01

The effects of process parameters on the crystallization and morphology of hydroxyapatite (Ca10(PO4)6(OH)2, HA) powders synthesized from dicalcium phosphate dihydrate (CaHPO4·2H2O, DCPD) using a hydrolysis method have been investigated. X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectra, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) were used to characterize the synthesized powders. When DCPD underwent hydrolysis in 2.5 NaOH solution (Na(aq)) at 303 K to 348 K (30 °C to 75 °C) for 1 hour, the XRD results revealed that HA was obtained for all the as-dried samples. The SEM morphology of the HA powders for DCPD hydrolysis produced at 348 K (75 °C) shows regular alignment and a short rod shape with a size of 200 nm in length and 50 nm in width. With DCPD hydrolysis in 2.5 M NaOH(aq) holding at 348 K (75 °C) for 1 to 24 hours, XRD results demonstrated that all samples were HA and no other phases could be detected. Moreover, the XRD results also show that all the as-dried powders still maintained the HA structure when DCPD underwent hydrolysis in 0.1 to 5 M NaOH(aq) at 348 K (75 °C) for 1 hour. Otherwise, the full transformation from HA to octa-calcium phosphate (OCP, Ca8H2(PO4)6·5H2O) occurred when hydrolysis happened in 10 M NaOH(aq). FT-IR spectra analysis revealed that some carbonated HA (Ca10(PO4)6(CO3), CHA) had formed. The SEM morphology results show that the 60 to 65 nm width of the uniformly long rods with regular alignment formed in the HA powder aggregates when DCPD underwent hydrolysis in 2.5 M NaOH(aq) at 348 K (75 °C) for 1 hour.

Self-Renewing Microns-Thick Biopolymer Brush Made of Hyaluronan under Active Synthesis

NASA Astrophysics Data System (ADS)

Wei, W.; Washburn, J.; Weigel, P.; Curtis, J. E.

Hyaluronan (HA) is a large anionic polysaccharide distributed throughout many vertebrate tissues. We introduce a technology to produce dynamic HA polymer brush interfaces. The strategy relies on the enzyme hyaluronan synthase (HA synthase), which synthesizes and extrudes HA polymers up to 20 microns in length. We show that interfaces decorated by HA synthase-rich membrane fragments robustly produce polymer brushes of predictable heights and concentration profiles. The brush thickness can be tuned by the duration of growth or the enzyme density in the membranes. The system is self-renewing in that old polymers desorb and new polymers are produced. The brush can also be replenished after enzymatic removal multiple times. The large extent of the polymer interface allows for characterization of the brush architecture and for studying dynamic processes inside the brush using optical microscopy. At low ionic strengths (1 mM), we measure one of the largest polymer brushes yet reported, an average of 7.8 microns thick. For applications that require a stable brush interface, we have covalently reinforced the HA to the surfaces, and demonstrated that the brush is stable for at least two months. This self-renewing, dynamic biopolymer brush has great potential as a new biomaterial for implants, antifouling, tissue engineering and drug delivery.

Micromorphological effect of calcium phosphate coating on compatibility of magnesium alloy with osteoblast

PubMed Central

Hiromoto, Sachiko; Yamazaki, Tomohiko

2017-01-01

Abstract Octacalcium phosphate (OCP) and hydroxyapatite (HAp) coatings were developed to control the degradation speed and to improve the biocompatibility of biodegradable magnesium alloys. Osteoblast MG-63 was cultured directly on OCP- and HAp-coated Mg-3Al-1Zn (wt%, AZ31) alloy (OCP- and HAp-AZ31) to evaluate cell compatibility. Cell proliferation was remarkably improved with OCP and HAp coatings which reduced the corrosion and prevented the H2O2 generation on Mg alloy substrate. OCP-AZ31 showed sparse distribution of living cell colonies and dead cells. HAp-AZ31 showed dense and homogeneous distribution of living cells, with dead cells localized over and around corrosion pits, some of which were formed underneath the coating. These results demonstrated that cells were dead due to changes in the local environment, and it is necessary to evaluate the local biocompatibility of magnesium alloys. Cell density on HAp-AZ31 was higher than that on OCP-AZ31 although there was not a significant difference in the amount of Mg ions released in medium between OCP- and HAp-AZ31. The outer layer of OCP and HAp coatings consisted of plate-like crystal with a thickness of around 0.1 μm and rod-like crystals with a diameter of around 0.1 μm, respectively, which grew from a continuous inner layer. Osteoblasts formed focal contacts on the tips of plate-like OCP and rod-like HAp crystals, with heights of 2–5 μm. The spacing between OCP tips of 0.8–1.1 μm was wider than that between HAp tips of 0.2–0.3 μm. These results demonstrated that cell proliferation depended on the micromorphology of the coatings which governed spacing of focal contacts. Consequently, HAp coating is suitable for improving cell compatibility and bone-forming ability of the Mg alloy. PMID:28179963

Micromorphological effect of calcium phosphate coating on compatibility of magnesium alloy with osteoblast

NASA Astrophysics Data System (ADS)

Hiromoto, Sachiko; Yamazaki, Tomohiko

2017-12-01

Octacalcium phosphate (OCP) and hydroxyapatite (HAp) coatings were developed to control the degradation speed and to improve the biocompatibility of biodegradable magnesium alloys. Osteoblast MG-63 was cultured directly on OCP- and HAp-coated Mg-3Al-1Zn (wt%, AZ31) alloy (OCP- and HAp-AZ31) to evaluate cell compatibility. Cell proliferation was remarkably improved with OCP and HAp coatings which reduced the corrosion and prevented the H2O2 generation on Mg alloy substrate. OCP-AZ31 showed sparse distribution of living cell colonies and dead cells. HAp-AZ31 showed dense and homogeneous distribution of living cells, with dead cells localized over and around corrosion pits, some of which were formed underneath the coating. These results demonstrated that cells were dead due to changes in the local environment, and it is necessary to evaluate the local biocompatibility of magnesium alloys. Cell density on HAp-AZ31 was higher than that on OCP-AZ31 although there was not a significant difference in the amount of Mg ions released in medium between OCP- and HAp-AZ31. The outer layer of OCP and HAp coatings consisted of plate-like crystal with a thickness of around 0.1 μm and rod-like crystals with a diameter of around 0.1 μm, respectively, which grew from a continuous inner layer. Osteoblasts formed focal contacts on the tips of plate-like OCP and rod-like HAp crystals, with heights of 2-5 μm. The spacing between OCP tips of 0.8-1.1 μm was wider than that between HAp tips of 0.2-0.3 μm. These results demonstrated that cell proliferation depended on the micromorphology of the coatings which governed spacing of focal contacts. Consequently, HAp coating is suitable for improving cell compatibility and bone-forming ability of the Mg alloy.

Impact of Hormonal Contraception and Weight Loss on HDL-C efflux and Lipoprotein Particles in Women with Polycystic Ovary Syndrome

PubMed Central

Dokras, Anuja; Playford, Martin; Kris-Etherton, Penny M.; Kunselman, Allen R.; Stetter, Christy M.; Williams, Nancy I.; Gnatuk, Carol L.; Estes, Stephanie J.; Sarwer, David B; Allison, Kelly C; Coutifaris, Christos; Mehta, Nehal; Legro, Richard S

2017-01-01

Objective To study the effects of oral contraceptive pills (OCP), the first line treatment for PCOS, on HDL-C function (reverse cholesterol efflux capacity) and lipoprotein particles measured by NMR spectroscopy. Design Secondary analysis of a randomized controlled trial (OWL-PCOS) of OCP or Lifestyle (intensive lifestyle modification) or Combined (OCP+Lifestyle) treatment for 16 weeks. Patients 87 overweight/obese women with PCOS at two academic centers Measurements Change in HDL-C efflux capacity and lipoprotein particles. Results HDL-C efflux capacity increased significantly at 16 weeks in the OCP group (0.11; 95% CI 0.03, 0.18, p=0.008) but not in the Lifestyle (p=0.39) or Combined group (p=0.18). After adjusting for HDL-C and TG levels, there was significant mean change in efflux in the Combined group (0.09; 95% CI 0.01, 0.15; p=0.01). Change in HDL-C efflux correlated inversely with change in serum testosterone (rs = −0.21; p=0.05). In contrast, OCP use induced an atherogenic LDL-C profile with increase in small (p=0.006) and large LDL-particles (p=0.002). Change in small LDL-particles correlated with change in serum testosterone (rs = −0.31, p=0.009) and insulin sensitivity index (rs = −0.31, p=0.02). Both Lifestyle and Combined groups did not show significant changes in the atherogenic LDL-particles. Conclusions OCP use is associated with improved HDL-C function and a concomitant atherogenic LDL-C profile. Combination of a Lifestyle program with OCP use improved HDL-C function and mitigated adverse effects of OCP on lipoproteins. Our study provides evidence for use of OCP in overweight/obese women with PCOS when combined with Lifestyle changes. PMID:28199736

Oral contraceptives and dysmenorrhea.

PubMed

Cholst, I N; Carlon, A T

1987-01-01

This artical examines the risks and benefits associated with use of the oral contraceptive pill (OCP) by adolescents and the various alternatives and methods of prescribing OCPs. Any adolescent who is either sexually active or contemplating sexual activity should be offered a contraceptive method that is appropriate to her individual needs. The contraceptive needs to be highly effective, safe and within the means and desires of the adolescent. For the majority of teenagers, the contraceptive of choice will be the OCP. The IUD should almost never be prescribed to the adolescent. Most OCPs marketed today are combination pills containing both an estrogen and a progestin in each pill. A variety of contraceptive actions combines to create a contraceptive method that is 99.3-99.9% effective. OCPs provide some protection against the development of pelvic inflammatory disease (PID). Oral contraceptives also decrease the incidence of anemia by decreasing the amount and duration of menstrual flow. Ovarian cysts do not form in the ovaries of the OCP user. On the other hand, a serious risk of the use of OCPs is the increased danger of thromboembolic events including deep venous thrombosis, pulmonary embolus, and myocardial infarction. The increased risk of myocardial infarction in OCP users is additive with other risk factors including hypertension, hypercholesterolemia, cigarette smoking, obesity, diabetes mellitus, and age. OCP use seems to provide some protection against development of endometrial or ovarian cancer. Oral contraceptives are associated with the development of benign hepatocellular adenomas. A variety of metabolic and hormonal alterations also occur in pill users. Most appropriate for the adolescent is a formulation containing a low dose of estrogen because of the decreased risk of thromboembolic complications. Dysmenorrhea effects more than 1/2 of female adolescents, and can best be treated with ibuprofen.

The efficacy of online communication platforms for plastic surgeons providing extended disaster relief.

PubMed

Fan, Kenneth L; Avashia, Yash J; Dayicioglu, Deniz; DeGennaro, Vincent A; Thaller, Seth R

2014-04-01

Immediately after the January 2010 earthquake in Haiti, plastic surgeons provided disaster relief services through the University of Miami Miller School of Medicine for 5 months. To improve surgical care and promote awareness of plastic surgery's role in humanitarian assistance, an online communication platform (OCP) was initiated. An OCP is a Web-based application combining Web blogging, picture uploading, news posting, and private messaging systems into a single platform. The purpose of this study was to analyze the use of OCP during disaster relief. Surgeries performed during the period from January 13 to May 28, 2010, were documented. The OCP was established with 4 priorities: ease of use, multimedia integration, organization capabilities, and security. Web traffic was documented. A 17-question survey was administered to 18 plastic surgeons who used the OCP after 1 year to assess their attitudes and perceptions. From January 13 to May 28, 2010, 413 operations were performed at the field hospital. Of the overall number of procedures, 46.9% were performed by plastic surgery teams. In a year, beginning from January 12, 2011, the OCP had 1117 visits with 530 absolute unique visitors. Of 17 plastic surgeons, 71% responded that the OCP improved follow-up and continuity of care by debriefing rotating plastic surgery teams. One hundred percent claimed that the OCP conveyed the role of plastic surgeons with the public. Results demonstrate the necessity of OCP during disaster relief. Online communication platform permitted secure exchange of surgical management details, follow-up, photos, and miscellaneous necessary recommendations. Posted experiences and field hospital progress assisted in generating substantial awareness regarding the significant role and contribution played by plastic surgeons in disaster relief.

Predictors of Serum Chlorinated Pesticide Concentrations among Prepubertal Russian Boys

PubMed Central

Williams, Paige L.; Burns, Jane S.; Sergeyev, Oleg; Korrick, Susan A.; Lee, Mary M.; Birnbaum, Linda S.; Revich, Boris; Altshul, Larisa M.; Patterson, Donald G.; Turner, Wayman E.; Hauser, Russ

2013-01-01

Background: Few studies have evaluated predictors of childhood exposure to organochlorine pesticides (OCPs), a class of lipophilic persistent chemicals. Objectives: Our goal was to identify predictors of serum OCP concentrations—hexachlorobenzene (HCB), β-hexachlorocyclohexane (β-HCH), and p,p-dichlorodiphenyldichloroethylene (p,p´-DDE)—among boys in Chapaevsk, Russia. Methods: Between 2003 and 2005, 499 boys 8–9 years of age were recruited in a prospective cohort. The initial study visit included a physical examination; blood collection; health, lifestyle, and food-frequency questionnaires; and determination of residential distance from a local factory complex that produced HCB and β-HCH. Fasting serum samples were analyzed for OCPs at the U.S. Centers for Disease Control and Prevention. General linear regression models were used to identify predictors of the boys’ serum HCB, β-HCH, and p,p´-DDE concentrations. Results: Among 355 boys with OCP measurements, median serum HCB, β-HCH, and p,p´-DDE concentrations were 158, 167, and 284 ng/g lipid, respectively. Lower body mass index, longer breastfeeding duration, and local dairy consumption were associated with higher concentrations of OCPs. Boys who lived < 2 km from the factory complex had 64% (95% CI: 37, 96) and 57% (95% CI: 32, 87) higher mean HCB and β-HCH concentrations, respectively, than boys who lived ≥ 5 km away. Living > 3 years in Chapaevsk predicted higher β-HCH concentrations, and having parents who lacked a high school education predicted higher p,p´-DDE concentrations. Conclusions: Among this cohort of prepubertal Russian boys, predictors of serum OCPs included consumption of local dairy products, longer local residence, and residential proximity to the local factory complex. Citation: Lam T, Williams PL, Burns JS, Sergeyev O, Korrick SA, Lee MM, Birnbaum LS, Revich B, Altshul LM, Patterson DG Jr, Turner WE, Hauser R. 2013. Predictors of serum chlorinated pesticide concentrations among prepubertal Russian boys. Environ Health Perspect 121:1372–1377; http://dx.doi.org/10.1289/ehp.1306480 PMID:23955839

Determining Historical Pesticide Deposition on Cape Cod through Sediment Core Analysis:A Validation of GIS as An Exposure Assessment Tool

NASA Astrophysics Data System (ADS)

Feingold, B. J.; Benoit, G.; Rudel, R.

2006-12-01

Geographic Information Systems (GIS) has emerged as a powerful tool to assess current and historical exposure to environmental pollutants. GIS aids in the visualization and understanding of associations between exposure to contaminants and disease. This study is an example of the bridge between environmental science and public health and of how new technology such as GIS can be incorporated into these fields to strengthen both the research and the communication of scientific results. It attempts to validate a GIS-based aerial drift model which predicts the residential exposure to and boundaries of historical organochlorine pesticide (OCP) drift from applications on cranberry bogs, tree pest sprayings and others by analytically quantifying the historical pesticide deposition in a transect of lakes radiating from a distinct spray source. This model was previously used to assess historical residential exposure to OCPs in an environmental epidemiological case-control study of breast cancer incidence on Cape Cod, MA, where the incidence rate of the disease is significantly higher than in the rest of the state. The model's validation in this current study is essential to establishing its predictive ability and thus, its further use. Ground truthing of the model was done through the collection and analysis of sediment cores along a transect of five hydrologically independent kettle ponds radiating from a distinct OCP tree-pest spray area. Measurements of OCP concentrations, total carbon and total organic carbon were determined, and dating of the sediments was completed using 210Pb and verified using 137Cs. Each 50-cm core was sliced into 25 2- cm sections for the analyses, creating a fine-scale depositional history in each pond. Information gathered from each core allows for the determination of the extent and degree of dissipation of individual spray events of a known source area and determine how well the model fits the actual data.

Effect of a low dose combined oral contraceptive pill on the hormonal profile and cycle outcome following COS with a GnRH antagonist protocol in women over 35 years old.

PubMed

Bakas, Panagiotis; Hassiakos, Dimitrios; Grigoriadis, Charalampos; Vlahos, Nikolaos F; Liapis, Angelos; Creatsas, George

2014-11-01

This prospective study examines if pre-treatment with two different doses of an oral contraceptive pill (OCP) modifies significantly the hormonal profile and/or the IVF/ICSI outcome following COS with a GnRH antagonist protocol. Infertile patients were allocated to receive either OCP containing 0.03 mg of ethinylestradiol and 3 mg of drospirenone, or OCP containing 0.02 mg of ethinylestradiol and 3 mg of drospirenone prior to initiation of controlled ovarian stimulation (COS) with recombinant gonadotropins on a variable multi-dose antagonist protocol (Ganirelix), while the control group underwent COS without OCP pretreatment. Lower dose OCP was associated with recovery of FSH on day 3 instead of day 5, but the synchronization of the follicular cohort, the number of retrieved oocytes and the clinical pregnancy rate were similar to higher dose OCP.

Mass spectrometry footprinting reveals the structural rearrangements of cyanobacterial orange carotenoid protein upon light activation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Haijun; Zhang, Hao; King, Jeremy D.

The orange carotenoid protein (OCP), a member of the family of blue light photoactive proteins, is required for efficient photoprotection in many cyanobacteria. Photoexcitation of the carotenoid in the OCP results in structural changes within the chromophore and the protein to give an active red form of OCP that is required for phycobilisome binding and consequent fluorescence quenching. We characterized the light-dependent structural changes by mass spectrometry-based carboxyl footprinting and found that an α helix in the N-terminal extension of OCP plays a key role in this photoactivation process. Although this helix is located on and associates with the outsidemore » of the β-sheet core in the C-terminal domain of OCP in the dark, photoinduced changes in the domain structure disrupt this interaction. We propose that this mechanism couples light-dependent carotenoid conformational changes to global protein conformational dynamics in favor of functional phycobilisome binding, and is an essential part of the OCP photocycle.« less

Residue behavior of organochlorine pesticides during the production process of yogurt and cheese.

PubMed

Duan, Jing; Cheng, Zheng; Bi, Jiawei; Xu, Yangguang

2018-04-15

The presence of organochlorine pesticides (OCPs) in dairy products can lead to human exposure. This study investigated the behavior of OCP residues in milk during yogurt and cheese production. Gas chromatography with electron-capture detection (GC-ECD) was used to detect α-hexachlorocyclohexane (HCH), hexachlorobenzene (HCB), γ-HCH, g-chlordane, and α-chlordane in fresh milk, yogurt, and cheese. The results showed that fermentation reduced the residual concentration of OCPs in yogurt, with processing factors (PFs) ranging from 0.42 to 0.64. The reductions in residue levels during fermentation were due to the activity of the starter. The cheese making process increased the residual concentration of OCPs in cheese compared to raw milk, with PFs ranging from 2.37 to 4.93. Additionally, milk, yogurt, and cheese samples were purchased from local markets and OCP levels were analyzed. The target OCPs ranged from ND to 16.50 μg/kg in these samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

The influence of hormonal contraception on mood and sexual interest among adolescents.

PubMed

Ott, Mary A; Shew, Marcia L; Ofner, Susan; Tu, Wanzhu; Fortenberry, J Dennis

2008-08-01

Mood and sexual interest changes are commonly cited reasons for discontinuing hormonal contraceptives. Data, however, are inconsistent and limited to adult users. We examined associations of hormonal contraceptive use with mood and sexual interest among adolescents. We recruited 14-17-year-old women from primary care clinics and followed them longitudinally for up to 41 months. Participants completed face-to-face interviews quarterly and two 12-week periods of daily diary collection per year. On daily diaries, participants recorded positive mood, negative mood, and sexual interest. We classified 12-week diary periods as "stable OCP use," "non-use," "initiated use," "stopped use," and "DMPA use" based on self-report of oral contraceptive pill (OCP) use and depot medroxyprogesterone acetate (DMPA) use from medical charts. Diary periods were the unit of analysis. Participants could contribute more than one diary period. We analyzed data using linear models with a random intercept and slope across weeks in a diary period, an effect for contraceptive group, and an adjustment for age at the start of a diary period. Mean weekly positive mood was higher in diary periods characterized by stable OCP use, compared to other groups. Mean weekly negative mood was lower in diary periods characterized by stable OCP use and higher in periods characterized by DMPA use. Periods characterized by stable OCP use additionally showed less mood variation than other groups. Changes in mood among adolescent hormonal contraceptive users differed from those anticipated for adult users. Attention to adolescent-specific changes in mood and sexual interest may improve contraceptive adherence.

Molecular imprinted opal closest-packing photonic crystals for the detection of trace 17β-estradiol in aqueous solution.

PubMed

Sai, Na; Wu, Yuntang; Sun, Zhong; Huang, Guowei; Gao, Zhixian

2015-11-01

A novel opal closest-packing (OCP) photonic crystal (PC) was prepared by the introduction of molecular imprinting technique into the OCP PC. This molecular imprinted (MI)-OCP PC was fabricated via a vertical convective self-assembly method using 17β-estradiol (E2) as template molecules for monitoring E2 in aqueous solution. Morphology characterization showed that the MI-OCP PC possessed a highly ordered three-dimensional (3D) periodically-ordered structure, showing the desired structural color. The proposed PC material displayed a reduced reflection intensity when detecting E2 in water environment, because the molecular imprinting recognition events make the optical characteristics of PC change. The Bragg diffraction intensity decreased by 19.864 a.u. with the increase of E2 concentration from 1.5 ng mL(-1) to 364.5 ng mL(-1) within 6 min, whereas there were no obvious peak intensity changes for estriol, estrone, cholesterol, testosterone and diethylstilbestrol, indicating that the MI-OCP PC had selective and rapid response for E2 molecules. The adsorption results showed that the OCP structure and homogeneous layers were created in the MI-OCP PC with higher adsorption capacity. Thus, it was learned the MI-OCP PC is a simple prepared, sensitive, selective, and easy operative material, which shows promising use in routine supervision for residue detection in food and environment. Copyright © 2015 Elsevier B.V. All rights reserved.

Fast Simulators for Satellite Cloud Optical Centroid Pressure Retrievals, 1. Evaluation of OMI Cloud Retrievals

NASA Technical Reports Server (NTRS)

Joiner, J.; Vasilkov, A. P.; Gupta, Pawan; Bhartia, P. K.; Veefkind, Pepijn; Sneep, Maarten; deHaan, Johan; Polonsky, Igor; Spurr, Robert

2011-01-01

We have developed a relatively simple scheme for simulating retrieved cloud optical centroid pressures (OCP) from satellite solar backscatter observations. We have compared simulator results with those from more detailed retrieval simulators that more fully account for the complex radiative transfer in a cloudy atmosphere. We used this fast simulator to conduct a comprehensive evaluation of cloud OCPs from the two OMI algorithms using collocated data from CloudSat and Aqua MODIS, a unique situation afforded by the A-train formation of satellites. We find that both OMI algorithms perform reasonably well and that the two algorithms agree better with each other than either does with the collocated CloudSat data. This indicates that patchy snow/ice, cloud 3D, and aerosol effects not simulated with the CloudSat data are affecting both algorithms similarly. We note that the collocation with CloudSat occurs mainly on the East side of OMI's swath. Therefore, we are not able to address cross-track biases in OMI cloud OCP retrievals. Our fast simulator may also be used to simulate cloud OCP from output generated by general circulation models (GCM) with appropriate account of cloud overlap. We have implemented such a scheme and plan to compare OMI data with GCM output in the near future.

English Teachers' Moderating and Participating in OCPs

ERIC Educational Resources Information Center

Pino-Silva, Juan; Mayora, Carlos A.

2010-01-01

Online Communities of Practice (OCPs) are among the most accessible tools for EFL/ESL teachers' co-construction of knowledge and self-directed learning. Despite the welcomed proliferation of EFL/ESL teachers' OCPs, concomitant research on collaboration is noticeably lagging behind. The present paper is just a preliminary look at moderation and…

Insulin-sensitising drugs versus the combined oral contraceptive pill for hirsutism, acne and risk of diabetes, cardiovascular disease, and endometrial cancer in polycystic ovary syndrome.

PubMed

Costello, M; Shrestha, B; Eden, J; Sjoblom, P; Johnson, N

2007-01-24

Insulin-sensitizing drugs (ISDs) have recently been advocated as possibly a safer and more effective long-term treatment than the oral contraceptive pill (OCP) in women with polycystic ovary syndrome (PCOS). It is important to directly compare the efficacy and safety of ISDs versus OCPs in the long-term treatment of women with PCOS. To assess the effectiveness and safety of ISDs versus the OCP (alone or in combination) in improving clinical, hormonal, and metabolic features of PCOS. We searched the Cochrane Menstrual Disorders and Subfertility Group Trials Register (September 2005), Cochrane Central Register of Controlled Trials (CENTRAL (Ovid), third quarter 2005), MEDLINE (1966 to September 2005), CINAHL (1982 to September 2005), and EMBASE (1988 to September 2005). References of the identified articles were handsearched, and pharmaceutical companies and experts in the field were also contacted for additional relevant studies. Randomised controlled trials which compared ISDs versus the OCP (alone or in combination). Performed independently by two review authors. Six trials were included for analysis, four of which compared metformin versus OCP (104 participants) and two of which compared OCP combined with metformin versus OCP alone (70 participants). Limited data demonstrated no evidence of difference in effect between metformin and the OCP on hirsutism and acne. There was either insufficient or no data on the relative efficacy of metformin or the OCP (alone or in combination) for preventing the development of diabetes, cardiovascular disease, or endometrial cancer. Metformin was less effective than the OCP in improving menstrual pattern (Peto odds ratio (OR) 0.08, 95% CI 0.01 to 0.45). Metformin resulted in a higher incidence of gastrointestinal (Peto OR 7.75, 95% CI 1.32 to 45.71), and a lower incidence of non-gastrointestinal (Peto OR 0.11, 95% CI 0.03 to 0.39), severe adverse effects requiring stopping of medication. Metformin was less effective in reducing serum androgen levels (total testosterone: weighted mean difference (WMD) 0.54, 95% CI 0.22 to 0.86; free androgen index: WMD 3.69, 95% CI 2.56 to 4.83). Metformin was more effective than the OCP in reducing fasting insulin (WMD -3.46, 95% CI -5.39 to -1.52) and not increasing triglyceride (WMD -0.48, 95% -0.86 to -0.09) levels, but there was insufficient evidence regarding comparative effects on reducing fasting glucose or cholesterol levels. Up to 12-months treatment with the OCP is associated with an improvement in menstrual pattern and serum androgen levels compared with metformin; but metformin treatment results in a reduction in fasting insulin and lower triglyceride levels than with the OCP. Side-effect profiles differ between the two drugs. There is either extremely limited or no data on important clinical outcomes such as the development of diabetes, cardiovascular disease, or endometrial cancer. There are no data comparing ISDs other than metformin (that is rosiglitazone, pioglitazone, and D-chiro-inositol) versus OCPs (alone or in combination).

Mapping soil erosion hotspots and assessing the potential impacts of land management practices in the highlands of Ethiopia

NASA Astrophysics Data System (ADS)

Tamene, Lulseged; Adimassu, Zenebe; Ellison, James; Yaekob, Tesfaye; Woldearegay, Kifle; Mekonnen, Kindu; Thorne, Peter; Le, Quang Bao

2017-09-01

An enormous effort is underway in Ethiopia to address soil erosion and restore overall land productivity. Modelling and participatory approaches can be used to delineate erosion hotspots, plan site- and context-specific interventions and assess their impacts. In this study, we employed a modelling interface developed based on the Revised Universal Soil Loss Equation adjusted by the sediment delivery ratio to map the spatial distribution of net soil loss and identify priority areas of intervention. Using the modelling interface, we also simulated the potential impacts of different soil and water conservation measures in reducing net soil loss. Model predictions showed that net soil loss in the study area ranges between 0.4 and 88 t ha- 1 yr- 1 with an average of 12 t ha- 1 yr- 1. The dominant soil erosion hotspots were associated with steep slopes, gullies, communal grazing and cultivated areas. The average soil loss observed in this study is higher than the tolerable soil loss rate estimated for the highland of Ethiopia. The scenario analysis results showed that targeting hotspot areas where soil loss exceeds 10 t ha- 1 yr- 1 could reduce net soil loss to the tolerable limit (< 2 t ha- 1 yr- 1). The spatial distribution of soil loss and the sediment yield reduction potential of different options provided essential information to guide prioritization and targeting. In addition, the results can help promoting awareness within the local community of the severity of the soil erosion problem and the potential of management interventions. Future work should include cost-benefit and tradeoff analyses of the various management options for achieving a given level of erosion reduction.

Contamination of organochlorine pesticides in the soils of the Campania Plain, Italy

NASA Astrophysics Data System (ADS)

Qu, Chengkai; Albanese, Stefano; Doherty, Angela; Chen, Wei; Lima, Annamaria; Piccolo, Alessandro; Arienzo, Michele; Qi, Shihua; De Vivo, Benedetto

2016-04-01

For the last several decades, organochlorine pesticides (OCPs) have been introduced into the environment through anthropogenic activity. Due to their volatility and persistence, OCPs may undergo long-range atmospheric transport and, as a result, can be redistributed globally. Exposure to OCPs can pose serious health risks, including certain cancers, birth defects, respiratory illness, dysfunctional reproductive and immune systems, greater susceptibility to disease and damages to the central and peripheral nervous systems. To date, only a handful of studies, have reported the OCPs contamination level in water, sediment and organisms in the Campania Region, however a regional study of the soil contamination is still lacking. In our study, the distribution, inventory and potential risk of OCPs, including Hexachlorocyclohexanes (HCHs) and Dichlorodiphenyltrichloroethanes (DDTs), and their correlation with environmental and anthropological factors were investigated in soils of the Campania Plain. The specific objectives of this study were to (I) investigate the residual levels, distribution and possible sources of legacy OCPs, and further estimate their mass inventories in soils of the Campania Plain, (II) analyze the impact of soil properties on contaminant distribution, and (III) evaluate the potential ecological and health risks of OCPs. The total concentrations of HCHs and DDTs has a geometric mean (GM) of 0.05 ng/g, and 14.4 ng/g, respectively. The significant difference in spatial variations of OCPs (Kruskal-Wallis test, P<0.05) was observed in the Campania Plain. Two specific areas exhibited higher concentrations of OCP residues: one situated in the Acerra-Marigliano conurbation with elevated HCHs and DDTs; and the other in the Sarno River basin which contains elevated levels of DDTs. The recent application of technical HCHs and DDTs in large quantities appears unlikely in light of the ratio of α-HCH/β-HCH and p,p'-DDT/p,p'-DDE, and the prohibition of the use of HCHs and DDTs in Italy nearly forty years ago. A significant positive correlation was observed between DDT residues and organic carbon suggesting a typical "secondary distribution" pattern. Based on Monte Carlo simulations, the mass inventories of legacy OCPs in soils of the Campania Plain were estimated to have a geometric mean of 17.3 metric tons.

Comparison of organochlorine pesticides occurrence, origin, and character in agricultural and industrial soils in Beijing.

PubMed

Shi, Yajuan; Lu, Yonglong; Wang, Tieyu; Wang, Guang; Luo, Wei

2009-10-01

The origin and occurrence of organochlorine pesticides [OCPs; hexachlorocyclohexanes (HCHs) and 1,1,1-trichloro-2,2- bis(p-chlorophenyl) ethane (DDTs)] in the surface and profile of soils from former OCPs production areas were compared with those of agricultural plots in Beijing, China in order to identify their characteristics, assess the eco-toxicological risk, and provide management suggestions. The comparison indicated heavier contamination caused by the production, storage, and waste disposal than the application of OCPs. Concentrations of HCHs and DDTs in topsoils varied by several orders of magnitude among different land-use groups. The concentrations (ng/g dry soil, geometric means) of HCHs (1958.2) and DDTs (3998.2) in the topsoils of former OCPs production factories were significantly higher than those in agricultural soils. The residue of DDTs and HCHs accumulated only on the surface of agricultural soil, but at depths ranging from 0 to 400 cm for the OCPs plant and warehouse. beta-HCH and p,p'-DDE dominated in the agricultural soils, whereas beta-HCH, gamma-HCH, p,p'-DDT, and p,p'-DDE were dominant in the industrial soils. The risk of examined OCPs in soils on human health was assessed in light of the Dutch and Canadian soil quality criteria, and the results indicated a high risk in the OCPs production factory area and the agricultural lands with large application. The results point to the need for urgent actions to evaluate long-term toxicity and preassessment for OCPs-related land-use management.

Spatial distribution, source apportionment and ecological risk assessment of residual organochlorine pesticides (OCPs) in the Himalayas.

PubMed

Devi, Ningombam Linthoingambi; Yadav, Ishwar Chandra; Raha, Priyankar; Shihua, Qi; Dan, Yang

2015-12-01

The Indian Himalayan Region (IHR) is one of the important mountain ecosystems among the global mountain system which support wide variety of flora, fauna, human communities and cultural diversities. Surface soil samples collected from IHR were analysed for 23 organochlorine pesticides (OCPs). The concentration of ∑OCPs ranged from 0.28 to 2143.96 ng/g (mean 221.54 ng/g) and was mostly dominated by DDTs. The concentration of ∑DDTs ranged from 0.28 to 2126.94 ng/g (mean 216.65 ng/g). Other OCPs such as HCHs, endosulfan and heptachlor, Aldrin and dieldrin were detected in lower concentration in IHR. Their concentrations in soil samples ranged from ND to 2.79 ng/g for HCHs, ND to 2.83 ng/g for endosulfans, NDto 1.46 ng/g for heptachlor, ND to 2.12 ng/g for Aldrin and ND to 1.81 ng/g for dieldrin. Spatial distribution of OCPs suggested prevalence of DDTs and HCHs at Guwahati and Itanagar, respectively. The close relationship between total organic carbon (TOC) and part of OCP compounds (especially α- and γ-HCH) indicated the important role of TOC in accumulation, binding and persistence of OCP in soil. Diagnostic ratio of DDT metabolites and HCH isomers showed DDT contamination is due to recent application of technical DDT and dicofol, and HCH contamination was due to mixture of technical HCH and lindane source. This was further confirmed by principal component analysis. Ecological risk analysis of OCP residues in soil samples concluded the moderate to severe contamination of soil.

Oncology care provider perspectives on exercise promotion in people with cancer: an examination of knowledge, practices, barriers, and facilitators.

PubMed

Nadler, Michelle; Bainbridge, Daryl; Tomasone, Jennifer; Cheifetz, Oren; Juergens, Rosalyn A; Sussman, Jonathan

2017-07-01

Despite the reported benefits of physical activity in alleviating the impact of cancer and its treatments, oncology care providers (OCPs) are not routinely discussing exercise with their patients, suggesting a knowledge to action gap. We sought to determine OCP's knowledge, beliefs, barriers, and facilitators to exercise discussion. A survey was administered to OCPs at the cancer center in Hamilton, Ontario. Questions comprised of demographics, knowledge and beliefs regarding exercise guidelines, and barriers and facilitators to exercise discussion. Analysis of survey responses was descriptive. Pearson's chi-squared test was used to examine select associations. There were 120 respondents (61% response rate) representing a diversity of professions. Approximately, 80% of OCPs were not aware of any exercise guidelines in cancer and self-reported poor knowledge on when, how, and which patients to refer to exercise programs. OCPs who reported meeting Canada's Physical Activity guidelines were significantly more likely to identify correct guidelines (p = 0.023) and to report good knowledge on how to provide exercise counseling (p = 0.014). Across OCP groups, barriers to exercise discussion included poor knowledge, lack of time, and safety concerns. Most felt that educational sessions and having an exercise specialist on the clinical team would be beneficial. OCPs have low knowledge regarding exercise counseling, but believe that discussing exercise is a multidisciplinary task and expressed a desire for further training. Interventions will require a multi-pronged approach including education for OCPs and guidance on assessment for exercise safety.

Model-Based Geostatistical Mapping of the Prevalence of Onchocerca volvulus in West Africa

PubMed Central

O’Hanlon, Simon J.; Slater, Hannah C.; Cheke, Robert A.; Boatin, Boakye A.; Coffeng, Luc E.; Pion, Sébastien D. S.; Boussinesq, Michel; Zouré, Honorat G. M.; Stolk, Wilma A.; Basáñez, María-Gloria

2016-01-01

Background The initial endemicity (pre-control prevalence) of onchocerciasis has been shown to be an important determinant of the feasibility of elimination by mass ivermectin distribution. We present the first geostatistical map of microfilarial prevalence in the former Onchocerciasis Control Programme in West Africa (OCP) before commencement of antivectorial and antiparasitic interventions. Methods and Findings Pre-control microfilarial prevalence data from 737 villages across the 11 constituent countries in the OCP epidemiological database were used as ground-truth data. These 737 data points, plus a set of statistically selected environmental covariates, were used in a Bayesian model-based geostatistical (B-MBG) approach to generate a continuous surface (at pixel resolution of 5 km x 5km) of microfilarial prevalence in West Africa prior to the commencement of the OCP. Uncertainty in model predictions was measured using a suite of validation statistics, performed on bootstrap samples of held-out validation data. The mean Pearson’s correlation between observed and estimated prevalence at validation locations was 0.693; the mean prediction error (average difference between observed and estimated values) was 0.77%, and the mean absolute prediction error (average magnitude of difference between observed and estimated values) was 12.2%. Within OCP boundaries, 17.8 million people were deemed to have been at risk, 7.55 million to have been infected, and mean microfilarial prevalence to have been 45% (range: 2–90%) in 1975. Conclusions and Significance This is the first map of initial onchocerciasis prevalence in West Africa using B-MBG. Important environmental predictors of infection prevalence were identified and used in a model out-performing those without spatial random effects or environmental covariates. Results may be compared with recent epidemiological mapping efforts to find areas of persisting transmission. These methods may be extended to areas where data are sparse, and may be used to help inform the feasibility of elimination with current and novel tools. PMID:26771545

Oral contraceptive pills induced hemichorea in an adolescent female with polycystic ovarian disease.

PubMed

Sharmila, Vijayan; Babu, Thirunavukkarasu Arun

2015-01-01

Chorea is a neurological adverse effect of oral contraceptive pills (OCPs). The onset of chorea following OCPs usage varies widely from few weeks to several years. We report a rare case of chorea which developed within a week of starting OCPs in an adolescent girl with polycystic ovarian disease.

Human health risk assessment, congener specific analysis and spatial distribution pattern of organochlorine pesticides (OCPs) through rice crop from selected districts of Punjab Province, Pakistan.

PubMed

Mumtaz, Mehvish; Qadir, Abdul; Mahmood, Adeel; Mehmood, Andleeb; Malik, Riffat Naseem; Li, Jun; Yousaf, Zubaida; Jamil, Nadia; Shaikh, Irfan Ahmed; Ali, Habib; Zhang, Gan

2015-04-01

To evaluate the screening level risk assessment of OCPs in rice (Oryza sativa L.) straw (n=20) and rice grains (n=20), samples were collected from different districts of Punjab Province, Pakistan. ∑OCPs' levels (ng g(-1)) in rice straw and grains ranged from 3.63 to 39.40, 2.72 to 49.89, respectively. DDTs were found predominant over the other detected OCP isomers followed by HCH and heptachlor. Results of one way ANOVA reflected no significant difference for OCPs' levels among sampling sites, except heptachlor for rice grains. ∑OCPs' concentration in rice straw samples was exceeding the minimal residual levels (MRLs) (Australian and Japanese). Results of dietary intake and risk assessment suggested that rice straw is not safe for animals to consume as fodder. Human health was suggested to have some carcinogenic risks by consumption of rice grains, however, no considerable hazardous risk (non-carcinogenic) to human health was found. Copyright © 2014 Elsevier B.V. All rights reserved.

Assessment of organochlorine pesticides residues in higher plants from oil exploration areas of Niger Delta, Nigeria.

PubMed

Sojinu, O Samuel; Sonibare, Oluwadayo O; Ekundayo, Olusegun O; Zeng, Eddy Y

2012-09-01

The concentrations and distributions of organochlorine pesticides (OCPs) in some higher plant samples collected from oil exploration areas of the Niger Delta, Nigeria were examined. The concentrations of Σ(25)OCP ranged from 82 to 424, 44 to 200 , 34 to 358, 33 to 106 and 16 to 75 ng/g in Olomoro, Oginni, Uzere, Irri and Calabar plants, respectively. The compositional profiles of the analysed OCPs in most of the plants showed no fresh inputs in the area. The OCPs detected in the samples could have resulted from pesticide usage for intense farming activities cum the use of pesticides to control household pests and insects in the area. Drilling fluids and corrosion inhibitors used in petroleum explorations also have chlorinated compounds as additives thereby serving as potential sources of OCPs. Among the studied plants, elephant grass showed high bioaccumulation and phytoremediation potentials of OCPs. The ΣHCH concentrations exceeded the allowable daily intake limit thereby serving as potential threat to humans. Copyright © 2012 Elsevier B.V. All rights reserved.

Diversity in mRNA expression of the serine-type carboxypeptidase ocpG in Aspergillus oryzae through intron retention.

PubMed

Ishida, Ken; Kuboshima, Megumi; Morita, Hiroto; Maeda, Hiroshi; Okamoto, Ayako; Takeuchi, Michio; Yamagata, Youhei

2014-01-01

Alternative splicing is thought to be a means for diversification of products by mRNA modification. Although some intron retentions are predicted by transcriptome analysis in Aspergillus oryzae, its physiological significance remains unknown. We found that intron retention occurred occasionally in the serine-type carboxypeptidase gene, ocpG. Analysis under various culture conditions revealed that extracellular nitrogen conditions influence splicing patterns; this suggested that there might be a correlation between splicing efficiency and the necessity of OcpG activity for obtaining a nitrogen source. Since further analysis showed that splicing occurred independently in each intron, we constructed ocpG intron-exchanging strain by interchanging the positions of intron-1 and intron-2. The splicing pattern indicated the probability that ocpG intron retention was affected by the secondary structures of intronic mRNA.

Relation Between Open Circuit Potential and Polarization Resistance with Rust and Corrosion Monitoring of Mild Steel

NASA Astrophysics Data System (ADS)

Choudhary, S.; Garg, A.; Mondal, K.

2016-07-01

The present work discusses continuous corrosion assessment from a unique correlation of open circuit potential (OCP) and linear polarization resistance with rust formation on mild steel after prolong exposure in 3.5% NaCl salt fog environment. The OCP measurement and linear polarization tests were carried out of the rusted samples only without the removal of rust. It also discusses the strong influence of the composition, fraction, and morphology of the rust layers with OCP and linear polarization resistance. The rust characterization was done after the measurement of OCP and linear polarization resistance of the rusted steel samples. Therefore, monitoring of both the OCP and linear polarization resistance of the rusted mild steels coupled with rust characterization could be used for easy and dynamic assessment of the nature of corrosion.

Internal exposure levels of typical POPs and their associations with childhood asthma in Shanghai, China.

PubMed

Meng, Ge; Feng, Yan; Nie, Zhiqing; Wu, Xiaomeng; Wei, Hongying; Wu, Shaowei; Yin, Yong; Wang, Yan

2016-04-01

Polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) are common persistent organic pollutants (POPs) that may be associated with childhood asthma. The concentrations of PBDEs, PCBs and OCPs were analyzed in pooled serum samples from both asthmatic and non-asthmatic children. The differences in the internal exposure levels between the case and control groups were tested (p value <0.0012). The associations between the internal exposure concentrations of the POPs and childhood asthma were estimated based on the odds ratios (ORs) calculated using logistic regression models. There were significant differences in three PBDEs, 26 PCBs and seven OCPs between the two groups, with significantly higher levels in the cases. The multiple logistic regression models demonstrated that the internal exposure concentrations of a number of the POPs (23 PCBs, p,p'-DDE and α-HCH) were positively associated with childhood asthma. Some synergistic effects were observed when the children were co-exposed to the chemicals. BDE-209 was positively associated with asthma aggravation. This study indicates the potential relationships between the internal exposure concentrations of particular POPs and the development of childhood asthma. Copyright © 2015 Elsevier Inc. All rights reserved.

Little emperors: behavioral impacts of China's One-Child Policy.

PubMed

Cameron, L; Erkal, N; Gangadharan, L; Meng, X

2013-02-22

We document that China's One-Child Policy (OCP), one of the most radical approaches to limiting population growth, has produced significantly less trusting, less trustworthy, more risk-averse, less competitive, more pessimistic, and less conscientious individuals. Our data were collected from economics experiments conducted with 421 individuals born just before and just after the OCP's introduction in 1979. Surveys to elicit personality traits were also used. We used the exogenous imposition of the OCP to identify the causal impact of being an only child, net of family background effects. The OCP thus has significant ramifications for Chinese society.

Highly efficient lithium composite anode with hydrophobic molten salt in seawater

NASA Astrophysics Data System (ADS)

Zhang, Yancheng; Urquidi-Macdonald, Mirna

A lithium composite anode (lithium/1-butyl-3-methyl-imidazoleum hexafluorophosphate (BMI +PF 6-)/4-VLZ) for primary lithium/seawater semi-fuel-cells is proposed to reduce lithium-water parasitic reaction and, hence, increase the lithium anodic efficiency up to 100%. The lithium composite anode was activated when in contact with artificial seawater (3% NaCl solution) and the output was a stable anodic current density at 0.2 mA/cm 2, which lasted about 10 h under potentiostatic polarization at +0.5 V versus open circuit potential (OCP); the anodic efficiency was indirectly measured to be 100%. With time, a small traces of water diffused through the hydrophobic molten salt, BMI +PF 6-, reached the lithium interface and formed a double layer film (LiH/LiOH). Accordingly, the current density decreased and the anodic efficiency was estimated to be 90%. The hypothesis of small traces of water penetrating the molten salt and reaching the lithium anode—after several hours of operation—is supported by the collected experimental current density and hydrogen evolution, electrochemical impedance spectrum analysis, and non-mechanistic interface film modeling of lithium/BMI +PF 6-.

Using Changes in Binding Globulins to Assess Oral Contraceptive Compliance

PubMed Central

Westhoff, Carolyn; Petrie, K.A.; Cremers, S.

2012-01-01

Background Validity of oral contraceptive pill (OCP) clinical trial results depends on participant compliance. Ethinyl estradiol (EE2) induces increases in hepatic binding globulin (BG) levels. Measuring these BG increases may provide an effective and convenient approach to distinguishing non-compliant from compliant OCP users in research settings. This analysis evaluated the usefulness of measuring increases in corticosteroid, sex hormone and thyroxine binding globulins (CBG, SHBG, TBG) as measures of OCP compliance. Methods We used frozen serum from a trial that compared ovarian suppression between normal weight and obese women randomized to one of two OCPs containing EE2 and levonorgestrel (LNG). Based on serial LNG measurements during the trial, 17% of participants were non-compliant. We matched non-compliant participants with compliant participants by age, BMI, ethnicity and OCP formulation. We measured CBG, SHBG and TBG levels, and compared change from baseline to 3-month follow-up between the non-compliant and compliant participants. Construction of receiver operator characteristic (ROC) curves allowed comparison of various BG measures. Results Changes in CBG and TBG distinguished OCP non-compliant users from compliant users (area under the ROC curve (AUROC), 0.86 and 0.89, p < 0.01). Changes in SHBG were less discriminating (AUROC 0.69) Conclusions EE2 induced increases in CBG and TBG provide a sensitive integrated marker of compliance with an LNG-containing OCP. PMID:22795088

Endocrine disrupting chemicals in New Orleans surface waters and Mississippi Sound sediments.

PubMed

Wang, Guangdi; Ma, Peng; Zhang, Qiang; Lewis, John; Lacey, Michelle; Furukawa, Yoko; O'Reilly, S E; Meaux, Shelley; McLachlan, John; Zhang, Shaoyuan

2012-05-01

Endocrine disrupting compounds (EDCs), represented by steroid hormones, organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and bisphenol A have been determined in four sediment cores from the Gulf of Mexico, from New Orleans surface water (Lake Pontchartrain and Mississippi River), and from the influent and effluent of a New Orleans municipal sewage treatment plant. During the five-month monitoring of selected EDCs in the Mississippi River (MR) and Lake Pontchartrain (LP) in 2008, 21 of 29 OCPs in MR and 17 of 29 OCPs in LP were detected; bisphenol A was detected in all of the samples. Steroid hormones (estrone, 17β-estradiol and 17α-ethinylestradiol) were detected occasionally. Total EDC (OCPs + PCBs + steroid hormones + bisphenol A) concentrations in the two surface water samples were found to vary from 148 to 1112 ng L(-1). Strong correlation of the distribution of total OCPs, total PCBs and total EDCs between solid and water phases was found in LP, while moderate or no correlation existed in MR. OCPs, PCBs, steroid hormones, and bisphenol A were all detected in the ocean sediments, and total EDCs were measured in the range of 77 to 1796 ng g(-1) dry sediment weight. The EDCs were also found in untreated and treated municipal sewage samples with a removal efficiency of 83% for OCPs but no removal efficiency for 17α-ethinylestradiol.

Levels of persistent organic pollutants in breast milk of Maya women in Yucatan, Mexico.

PubMed

Polanco Rodríguez, Ángel G; Inmaculada Riba López, M; Angel DelValls Casillas, T; León, Jesús Alfredo Araujo; Anjan Kumar Prusty, B; Álvarez Cervera, Fernando J

2017-02-01

In this study, 24 breast milk samples, obtained from rural Maya women, from municipalities of Yucatan, Mexico, were analyzed for organochlorine pesticide (OCP) residues by gas chromatography. Recent studies have shown that Maya communities have a poor perception about the proper usage and handling of OCP. The karstic soil in this area has a high vulnerability to groundwater pollution by the use of OCP in agriculture and livestock activities. The impact of the ecosystem on human health is much more critical due to the prevailing poverty and a very low educational level of these communities. About 30% of the Maya population consumes water directly from contaminated wells and sinkholes, resulting in a chronic exposure to OCP. The samples served to identify and quantify high levels of OCP residues (18.43 mg/kg of heptachlor epoxide and 1.92 mg/kg of endrin in the metropolitan zone; 2.10 mg/kg of dieldrin, 0.117 mg/kg of endosulfan II, 0.103 mg/kg of heptachlor, 0.178 mg/kg of endrin, and 0.127 mg/kg of endrin aldehyde in the main agricultural zone and on the west coast). The detected levels of OCP residues are a major concern and represent a potential risk to women and children in the region. This could be associated with the high rates of cervical uterine and breast cancer mortality in Yucatan. Thus, regulations on the usage of OCP and their enforcement are necessary, and it is important to establish a yearly monitoring program for OCP residues in breast milk and groundwater, as well as to implement health promotion programs for women in particular and the general population in general.

The partitioning behavior of persistent toxicant organic contaminants in eutrophic sediments: Coefficients and effects of fluorescent organic matter and particle size.

PubMed

He, Wei; Yang, Chen; Liu, Wenxiu; He, Qishuang; Wang, Qingmei; Li, Yilong; Kong, Xiangzhen; Lan, Xinyu; Xu, Fuliu

2016-12-01

In the shallow lakes, the partitioning of organic contaminants into the water phase from the solid phase might pose a potential hazard to both benthic and planktonic organisms, which would further damage aquatic ecosystems. This study determined the concentrations of polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), and phthalate esters (PAEs) in both the sediment and the pore water from Lake Chaohu and calculated the sediment - pore water partition coefficient (K D ) and the organic carbon normalized sediment - pore water partition coefficient (K OC ), and explored the effects of particle size, organic matter content, and parallel factor fluorescent organic matter (PARAFAC-FOM) on K D . The results showed that log K D values of PAHs (2.61-3.94) and OCPs (1.75-3.05) were significantly lower than that of PAEs (4.13-5.05) (p < 0.05). The chemicals were ranked by log K OC as follows: PAEs (6.05-6.94) > PAHs (4.61-5.86) > OCPs (3.62-4.97). A modified MCI model can predict K OC values in a range of log 1.5 at a higher frequency, especially for PAEs. The significantly positive correlation between K OC and the octanol - water partition coefficient (K OW ) were observed for PAHs and OCPs. However, significant correlation was found for PAEs only when excluding PAEs with lower K OW . Sediments with smaller particle sizes (clay and silt) and their organic matter would affect distributions of PAHs and OCPs between the sediment and the pore water. Protein-like fluorescent organic matter (C2) was associated with the K D of PAEs. Furthermore, the partitioning of PARAFAC-FOM between the sediment and the pore water could potentially affect the distribution of organic pollutants. The partitioning mechanism of PAEs between the sediment and the pore water might be different from that of PAHs and OCPs, as indicated by their associations with influencing factors and K OW . Copyright © 2016 Elsevier Ltd. All rights reserved.

Distribution profile, health risk and elimination of model atmospheric SVOCs associated with a typical municipal garbage compressing station in Guangzhou, South China

NASA Astrophysics Data System (ADS)

Li, Guiying; Sun, Hongwei; Zhang, Zhengyong; An, Taicheng; Hu, Jianfang

2013-09-01

Semi-volatile organic compounds (SVOCs) air pollution caused by municipal garbage compressing process was investigated at a garbage compressing station (GCS). The most abundant contaminants were phthalate esters (PAEs), followed by polycyclic aromatic hydrocarbons (PAHs) and organic chlorinated pesticides (OCPs). ∑16PAHs concentrations ranged from 58.773 to 68.840 ng m-3 in gas and from 6.489 to 17.291 ng m-3 in particulate phase; ∑20OCPs ranged from 4.181 to 5.550 ng m-3 and from 0.823 to 2.443 ng m-3 in gas and particulate phase, respectively; ∑15PAEs ranged from 46.498 to 87.928 ng m-3 and from 414.765 to 763.009 ng m-3 in gas and particulate phase. Lung-cancer risk due to PAHs exposure was 1.13 × 10-4. Both non-cancer and cancer risk levels due to OCPs exposure were acceptable. Non-cancer hazard index of PAEs was 4.57 × 10-3, suggesting safety of workers as only exposure to PAEs at GCS. At pilot scale, 60.18% of PAHs, 70.89% of OCPs and 63.2% of PAEs were removed by an integrated biotrickling filter-photocatalytic reactor at their stable state, and health risk levels were reduced about 50%, demonstrating high removal capacity of integrated reactor.

Spring Melt and the Redistribution of Organochlorine Pesticides in the Sea-Ice Environment: A Comparative Study between Arctic and Antarctic Regions.

PubMed

Bigot, Marie; Hawker, Darryl W; Cropp, Roger; Muir, Derek Cg; Jensen, Bjarne; Bossi, Rossana; Bengtson Nash, Susan M

2017-08-15

Complementary sampling of air, snow, sea-ice, and seawater for a range of organochlorine pesticides (OCPs) was undertaken through the early stages of respective spring sea-ice melting at coastal sites in northeast Greenland and eastern Antarctica to investigate OCP concentrations and redistribution during this time. Mean concentrations in seawater, sea-ice and snow were generally greater at the Arctic site. For example, α-HCH was found to have the largest concentrations of all analytes in Arctic seawater and sea-ice meltwater samples (224-253 and 34.7-48.2 pg·L -1 respectively compared to 1.0-1.3 and <0.63 pg·L -1 respectively for Antarctic samples). Differences in atmospheric samples were generally not as pronounced however. Findings suggest that sea-ice OCP burdens originate from both snow and seawater. The distribution profile between seawater and sea-ice showed a compound-dependency for Arctic samples not evident with those from the Antarctic, possibly due to full submersion of sea-ice at the former. Seasonal sea-ice melt processes may alter the exchange rates of selected OCPs between air and seawater, but are not expected to reverse their direction, which fugacity modeling indicates is volatilisation in the Arctic and net deposition in the Antarctic. These predictions are consistent with the limited current observations.

Polycystic ovary syndrome, oral contraceptives and metabolic issues: new perspectives and a unifying hypothesis.

PubMed

Nader, S; Diamanti-Kandarakis, E

2007-02-01

In the chronic treatment of polycystic ovary syndrome (PCOS), oral contraceptive pills (OCPs) are commonly used to induce regular menses, protect the endometrium and ameliorate androgenic symptoms. However, the long-term safety of OCP use in PCOS has not been established, and the literature reveals conflicting data concerning the metabolic effects of OCPs in this patient population, with outcomes ranging from improvement of glucose tolerance to the development of frank diabetes. This article presents new perspectives and a unifying hypothesis concerning the effects of OCPs on carbohydrate metabolism in PCOS and attempts to explain the divergent findings in published reports.

Neutrophil Collagenase, Gelatinase and Myeloperoxidase in Tears of Stevens-Johnson Syndrome and Ocular Cicatricial Pemphigoid Patients

PubMed Central

Arafat, Samer N.; Suelves, Ana M.; Spurr-Michaud, Sandra; Chodosh, James; Foster, C. Stephen; Dohlman, Claes H.; Gipson, Ilene K.

2013-01-01

Objective To investigate the levels of matrix metalloproteinases (MMPs), myeloperoxidase (MPO) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in tears of patients with Stevens-Johnson syndrome (SJS) and ocular cicatricial pemphigoid (OCP). Design Prospective non-interventional cohort study. Participants Four SJS patients (7 eyes), 19 OCP patients (37 eyes) and 20 post-phacoemulsification healthy controls (40 eyes). Methods Tear washes were collected from all patients and were analyzed for levels of MMP-2, -3, -7, -8, -9, -12, MPO and TIMP-1 using multi-analyte bead-based enzyme-linked immunosorbent assays (ELISA). Total MMP activity was determined using a fluorimetric assay. Correlation studies were performed between the various analytes within study groups. Main Outcome Measures Levels of MMP-2, -3, -7, -8, -9, -12, MPO and TIMP-1 (in ng/µg protein), total MMP activity (in relative fluorescent units/min/µg protein) in tears, MMP-8/TIMP-1, MMP-9/TIMP-1 ratios and the correlations between MMP-8 and MMP-9 and each MMP and MPO. Results MMP-8, MMP-9 and MPO levels were significantly elevated in SJS and OCP tears (SJS > OCP) when compared to controls. MMP activity was highest in SJS while OCP and controls showed lower and similar activities. TIMP-1 levels were decreased in SJS and OCP when compared to controls with OCP levels reaching significance. MMP-8/TIMP-1 and MMP-9/TIMP-1 ratios were markedly elevated in SJS and OCP tears (SJS > OCP) when compared to controls. Across all study groups, MMP-9 levels correlated strongly with MMP-8 and MPO levels and MMP-8 correlated with MPO but did not reach significance in SJS. There was no relationship between MMP-7 and MPO. Conclusions Since MMP-8 and MPO are produced by inflammatory cells, particularly neutrophils, the correlation data indicate that they may be the common source of elevated enzymes including MMP-9 in SJS and OCP tears. Elevated MMP/TIMP ratios and MMP activity suggest an imbalance in tear MMP regulation that may explain the predisposition of these patients to develop corneal melting and chronic complications associated with persistent inflammation. MPO in tears may be a sensitive and specific marker for the quantification of ocular inflammation. PMID:23962653

The effects of hydroxyapatite coatings on stress distribution near the dental implant bone interface

NASA Astrophysics Data System (ADS)

Jiang, W.; Wang, W. D.; Shi, X. H.; Chen, H. Z.; Zou, W.; Guo, Z.; Luo, J. M.; Gu, Z. W.; Zhang, X. D.

2008-11-01

The effects of different thickness of hydroxyapatite (HA) coatings on bone stress distribution near the dental implant-bone interface are very important factors for the HA-coated dental implant design and clinical application. By means of finite element analysis (FEA), the bone stress distributions near the dental implant coated with different thicknesses from 0 to 200 μm were calculated and analyzed under the 200 N chewing load. In all cases, the maximal von Mises stresses in the bone are at the positions near the neck of dental implant on the lingual side, and decrease with the increase of the HA coatings thickness. The HA coatings weaken the stress concentration and improve the biomechanical property in the bone, however, in HA coatings thickness range of 60-120 μm, the distinctions of that benefit are not obvious. In addition, considering the technical reason of HA coatings, we conclude that thickness of HA coatings range from 60 to 120 μm would be the better choice for clinical application.

Interface activation and surface characteristics of Ti/TiN/HA coated sintered stainless steels

NASA Astrophysics Data System (ADS)

Choe, Han-Cheol; Ko, Yeong-Mu

2006-02-01

Interface activation and surface characteristics of Ti/TiN/HA film coated sintered stainless steels (SSS) have been investigated by electrochemical and biocompatibility tests. HA (hydroxyapatite), Ti, and Ti/TiN film coatings were applied using electron-beam deposition method (EB-PVD). Ti, Ti/TiN, and Ti/TiN/HA film coated surfaces and layers were investigated by SEM and XPS. The coated films showed micro-columnar structure, and Ti/TiN/HA films were denser than Ti or HA-only film. The corrosion resistance of the HA coating was similar to that of Ti/TiN/HA film coating when Cu content reached 4 wt.%, but the corrosion resistance of the HA coating decreased when Cu content increased from 4 wt.% in 0.9% NaCl solution. Therefore, HA-only coating could ensure corrosion resistance when Cu content does not exceed 4 wt.%. The results of biocompatibility tests of SSS on dogs showed that bone formation and biocompatibility were favorable when Cu content did not exceed 4 wt.%. The biocompatibility with bone was generally favorable in Ti/TiN/HA film coating and HA-only coating, while bone formation was somewhat faster for the HA film coated surface than for the Ti/TiN/HA film coating. Also, good cell growth and osseointegration without toxicity were observed.

Predicting bioavailability and accumulation of organochlorine pesticides by Japanese medaka in the presence of humic acid and natural organic matter using passive sampling membranes.

PubMed

Ke, Runhui; Luo, Jianping; Sun, Liwei; Wang, Zijian; Spear, Philip A

2007-10-01

Adsorption to dissolved organic matter (DOM) may significantly decrease the freely dissolved concentration of many hydrophobic organic compounds and, hence, result in reduced bioavailability to aquatic organisms. Here, the suitability of using triolein-embedded cellulose acetate membrane (TECAM) as a biomimetic surrogate to assess the bioavailability of organochlorine pesticides (OCPs) in water in the presence of DOM was explored. The accumulation of OCPs was measured in TECAM and pelagic Japanese medaka (Oryzias latipes) in the laboratory after 12 h exposure to water containing different levels of Aldrich humic acid. Further, OCP uptake by TECAM and medaka in real aqueous environments was evaluated after 30 d exposures in two sites. Laboratory results showed that OCP uptake by medaka consistently decreased with increasing levels of humic acid in the range of 0-15 mg C/L in sample solutions. This tendency was closely mimicked by OCP accumulation in TECAM under the same conditions. Field results showed that TECAM accumulated similar OCP patterns as medaka (r2 = 0.92 for site 1 and r2 = 0.94 for site 2), although comparison of the in-field eight OCP concentrations in TECAM to those in medaka yielded approximately a factor of 3 (on a wet weight basis). These results suggest that the TECAM method can be used as a simple and useful tool to predict the bioavailability and bioaccumulation potential of poorly biotransformed organic compounds in pelagic fish in aqueous environment.

Developing a Screening Model to Establish Human Risk from Glacial Meltwater Release of Legacy Organochlorine Pollutants at the Silvretta Glacier in the Swiss Alps

NASA Astrophysics Data System (ADS)

Miner, K. R.

2017-12-01

Organochlorine pollutants (OCPs) banned globally by the Stockholm Convention in 2004 are reemerging from melting glaciers in numerous alpine ecosystems. Despite the known OCP influx from glaciers, a study of human risk from uptake of pesticides in glacial meltwater has never been attempted. Our study qualifies human uptake routes and quantifies risk utilizing published meltwater data from the Silvretta Glacier in the Swiss Alps in combination with methodology established by the US Environmental Protection Agency (EPA). Relatively high concentrations of OCPs in Silvretta glacier meltwater reflect proximity to use near high density populations and provide the best estimate of a 95th percentile human risk scenario. This screening level model assesses direct PCB risk to humans through consumption of fish tissue and meltwater. Our model shows a risk for both cancer and non-cancer disease impacts to children with lifetime exposure to glacial meltwater and an average local fish consumption. For adults with an abbreviated 30 year exposure timeframe, the risk for non-cancer effects is negligible and cancer effects are only barely above screening level. Populations that consume higher quantities of local fish are at greater risk, with additional challenges borne by children. Further direct study into the individual level risk to Swiss residents from glacial meltwater pollution is deemed necessary by our screening study.

Water-gas exchange of organochlorine pesticides at Lake Chaohu, a large Chinese lake.

PubMed

Ouyang, Hui-Ling; He, Wei; Qin, Ning; Kong, Xiang-Zhen; Liu, Wen-Xiu; He, Qi-Shuang; Yang, Chen; Jiang, Yu-Jiao; Wang, Qing-Mei; Yang, Bin; Xu, Fu-Liu

2013-04-01

Organochlorine pesticides (OCPs), a potential threat to ecosystems and human health, are still widely residual in the environment. The residual levels of OCPs in the water and gas phase were monitored in Lake Chaohu, a large Chinese lake, from March 2010 to February 2011. Nineteen types of OCPs were detected in the water with a total concentration of 7.27 ± 3.32 ng/l. Aldrin, DDTs and HCHs were the major OCPs in the water, accounting for 38.3%, 28.9% and 23.6% of the total, respectively. The highest mean concentration (12.32 ng/l) in the water was found in September, while the lowest (1.74 ng/l) was found in November. Twenty types of gaseous OCPs were detected in the atmosphere with a total concentration of 542.0 ± 636.5 pg/m(3). Endosulfan, DDTs and chlordane were the major gaseous OCPs in the atmosphere, accounting for 48.9%, 22.5% and 14.4% of the total, respectively. The mean concentration of gaseous OCPs was significantly higher in summer than in winter. o,p'-DDE was the main metabolite of DDT in both the water and gas phase. Of the HCHs, 52.3% existed as β-HCH in the water, while α-HCH (37.9%) and γ-HCH (30.9%) were dominant isomers in the gas phase. The average fluxes were -21.11, -3.30, -152.41, -35.50 and -1314.15 ng/(m(2) day) for α-HCH, γ-HCH, HCB, DDT and DDE, respectively. The water-gas exchanges of the five types of OCPs indicate that water was the main potential source of gaseous OCPs in the atmosphere. A sensitivity analysis indicated that the water-gas flux of α-HCH, γ-HCH and DDT is more vulnerable than that of HCB and DDE to the variation of the parameters. The possible source of the HCHs in the water was from the historical usage of lindane; however, that in the air was mainly from the recent usage of lindane. The technical DDT and dicofol might be the source of DDTs in the water and air.

Atomic force microscopy evaluation of aqueous interfaces of immobilized hyaluronan.

PubMed

Morra, Marco; Cassinelli, Clara; Pavesio, Alessandra; Renier, Davide

2003-03-15

Hyaluronan (HA) was immobilized on aminated glass surfaces in three different ways: by simple ionic interaction and by covalent linking at low density and at full density. In agreement with previous reports, in vitro experiments show that the outcome of fibroblast adhesion tests is markedly affected by the details of the coupling procedure, suggesting that different interfacial forces are operating at the aqueous/HA interface in the three cases investigated. The interfacial properties of the HA-coated surfaces were probed by force-distance curves obtained with the atomic force microscope (AFM). This approach readily shows significant differences among the tested samples, which are directly related to the coupling strategy and to results of cell adhesion tests. In particular, the range of interaction between the tip and the surface is much lower when HA is covalently linked than when it is ionically coupled, suggesting a more compact surface structure in the former case. Increasing HA surface density minimizes the interaction force between the surface and the AFM tip, likely reflecting more complete shielding by the HA chains of the underlying substrate. In summary, these measurements clearly show the different nature of the aqueous interfaces tested, and underline the role of this analytical approach in the development and control of finely tuned biomaterial surfaces.

The study of mechanical behavior on the interface between calcar-defect femur and restorations by means of finite element analysis

NASA Astrophysics Data System (ADS)

Shi, X. H.; Jiang, W.; Chen, H. Z.; Zou, W.; Wang, W. D.; Guo, Z.; Luo, J. M.; Gu, Z. W.; Zhang, X. D.

2008-11-01

The mechanical behaviors of calcar-defected femur and restorations under physiological load are the key factors that will greatly influence the success of femur calcar defect repairing, especially the stress distribution on the bone-restoration interface. 3D finite elements analysis (FEA) was used to analyze the mechanical characters on the interfaces between femoral calcar defects and bone cement or HA restorations. Under the load of two times of a human weight (1436.03 N) and with the increase of the defect dimension from 6 mm to 12 mm, the maximal stresses on the surface of restorations are from 7.06 MPa to 11.89 MPa for bone cement and 2.97-9 MPa for HA separately. In this condition, HA restoration will probably be broken on the bone-restoration interface when the defect diameter is beyond 8 mm. Furthermore, under the load of 1.5 times of a human weight, HA restoration would not be safe unless the defect dimension is smaller than 10 mm, because the maximal stress (4.62 MPa) on the restoration is only a little lower than compressive strength of HA, otherwise the bone fixation device should be applied to ensure the safety. It is relatively safe for all restorations under all the tested defect sizes when the load is just the weight of a human body.

Randomized clinical trial evaluating metformin versus oral contraceptive pills in the treatment of adolescents with polycystic ovarian syndrome.

PubMed

Al-Zubeidi, Hiba; Klein, Karen O

2015-07-01

Polycystic ovarian syndrome (PCOS) is characterized by irregular menses, elevated androgens, and insulin resistance. Little information is published about the treatment of adolescent PCOS. The aim of this study was to evaluate metformin versus oral contraceptive pills (OCP) in treating adolescent PCOS. Twenty-two girls were randomized to either treatment for 6 months. The outcomes variables included body mass index (BMI) and free testosterone (FT). BMI decreased in all patients (metformin p=0.004, OCP p=0.045). FT decreased significantly only with OCP. Insulin resistance measures decreased in all patients but did not reach significance. The only significant difference in any of the variables between the two groups was number of menses. BMI and FT remained less than baseline for 3 months off treatment. Metformin and OCP have a positive effect on BMI, which persists after treatment is discontinued. FT decreased with both treatments, but only reached significance with OCP.

Levels and distributions of organochlorine pesticides in the soil-groundwater system of vegetable planting area in Tianjin City, Northern China.

PubMed

Pan, Hong-Wei; Lei, Hong-Jun; He, Xiao-Song; Xi, Bei-Dou; Han, Yu-Ping; Xu, Qi-Gong

2017-04-01

To study the influence of long-term pesticide application on the distribution of organochlorine pesticides (OCPs) in the soil-groundwater system, 19 soil samples and 19 groundwater samples were collected from agricultural area with long-term pesticide application history in Northern China. Results showed that the composition of OCPs changed significantly from soil to groundwater. For example, ∑DDT, ∑HCH, and ∑heptachlor had high levels in the soil and low levels in the groundwater; in contrast, endrin had low level in the soil and high level in the groundwater. Further study showed that OCP distribution in the soil was significantly influenced by its residue time, soil organic carbon level, and small soil particle contents (i.d. <0.0002 mm). Correlation analysis also indicates that the distribution of OCPs in the groundwater was closely related to the levels of OCPs in the soil layer, which may act as a pollution source.

The investigation of atmospheric deposition distribution of organochlorine pesticides (OCPs) in Turkey

NASA Astrophysics Data System (ADS)

Cindoruk, S. Sıddık; Tasdemir, Yücel

2014-04-01

Atmospheric deposition is a significant pollution source leading to contamination of remote and clean sites, surface waters and soils. Since persistent organic pollutants (POPs) stay in atmosphere without any degradation, they can be transported and deposited to clean surfaces. Organochlorine pesticides are an important group of POPs which have toxic and harmful effects to living organisms and environment. Therefore, atmospheric deposition levels and characteristics are of importance to determine the pollution quantity of water and soil surfaces in terms of POPs. This study reports the distribution quantities of atmospheric deposition including bulk, dry, wet and air-water exchange of particle and gas phase OCPs as a result of 1-year sampling campaign. Atmospheric deposition distribution showed that the main mechanism for OCPs deposition is wet processes with percentage of 69 of total deposition. OCP compounds' deposition varied according to atmospheric concentration and deposition mechanism. HCH compounds were dominant pesticide species for all deposition mechanisms. HCH deposition constituted the 65% of Σ10OCPs.

The effects of rice canopy on the air-soil exchange of polycyclic aromatic hydrocarbons and organochlorine pesticides using paired passive air samplers.

PubMed

Wang, Yan; Wang, Shaorui; Luo, Chunling; Li, Jun; Ming, Lili; Zhang, Gan; Li, Xiangdong

2015-05-01

The rice canopy in paddy fields can influence the air-soil exchange of organic chemicals. We used paired passive air samplers to assess the exchange of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) in a paddy field, South China. Levels of OCPs and light PAHs were generally higher under the canopy than above it. We found that the rice canopy can physically obstruct the evaporation of most OCPs and light PAHs, and can also act as a barrier to the gaseous deposition of p,p'-DDT and heavy PAHs. Paddy fields can behave as a secondary source of OCPs and light PAHs. The homolog patterns of these two types of chemical varied slightly between the air below and above the rice canopy, implying contributions of different sources. Paired passive air samplers can be used effectively to assess the in situ air-soil exchange of PAHs and OCPs in subtropical paddy fields. Copyright © 2015 Elsevier Ltd. All rights reserved.

Anticipating surprise: Using agent-based alternative futures simulation modeling to identify and map surprising fires in the Willamette Valley, Oregon USA

Treesearch

David Hulse; Allan Branscomb; Chris Enright; Bart Johnson; Cody Evers; John Bolte; Alan Ager

2016-01-01

This article offers a literature-supported conception and empirically grounded analysis of surprise by exploring the capacity of scenario-driven, agent-based simulation models to better anticipate it. Building on literature-derived definitions and typologies of surprise, and using results from a modeled 81,000 ha study area in a wildland-urban interface of western...

Is the compressibility positive or negative in a strongly-coupled dusty plasma?

NASA Astrophysics Data System (ADS)

Goree, John; Ruhunusiri, W. D. Suranga

2014-10-01

In dusty plasmas, dust particles are often strongly coupled with a large Coulomb coupling parameter Γ, while the electrons and ions that share the same volume are weakly coupled. In most substances, compressibility β must be positive; otherwise there would be an explosive instability. In a multicomponent plasma, however, one could entertain the idea that β for a single strongly coupled component could be negative, provided that the restoring force from charge separation overwhelms the destabilizing effect. Indeed, the compressibility for a strongly-coupled dust component is assumed to be negative in three theories we identified in the literature for dust acoustic waves. These theories use a multi-fluid model, with an OCP (one component plasma) or Yukawa-OCP approach for the dust fluid. We performed dusty plasma experiments designed to determine the value of the inverse compressibility β-1, and in particular its sign. We fit an experimentally measured dispersion relation to theory, with β-1 as a free parameter, taking into account the systematic errors in the experiment and model. We find that β-1 is either positive, or it has a negligibly small negative value, which is not in agreement with the assumptions of the OCP-based theories. Supported by NSF and NASA.

Reduced Dental Plaque Formation in Dogs Drinking a Solution Containing Natural Antimicrobial Herbal Enzymes and Organic Matcha Green Tea

PubMed Central

2016-01-01

The results of an exploratory, multicenter clinical study confirmed the hypothesis that a novel, natural, and safe oral care product (OCP) reduced the rate of plaque formation on teeth of dogs consuming the OCP (antimicrobial plant-derived enzymes, organic matcha green tea, cultured dextrose, sodium bicarbonate, and ascorbic acid) compared to controls. Healthy dogs without periodontitis, of varying breeds, sex, and age, were recruited and enrolled, using nonrandomized stratification methods, into a control and treatment groups. Treatment group dogs drank only water into which OCP was suspended, for 28 days. Control group dogs drank their normal household water. On day 0 all teeth were cleaned by a veterinarian and gingivitis was assessed. On days 14, 21, and 28 plaque index, plaque thickness, gingivitis, freshness of breath, and general health were assessed. Over the 28 days of study, dogs on the OCP had significant reduction in plaque index and plaque thickness compared to controls. By day 14 OCP reduced plaque formation by 37%; the 28-day reduction in plaque index and coverage averaged 22% with no measurable gingivitis or calculus. Conclusion. Using the OCP attenuated dental plaque formation when consumed as normal drinking water and in the absence of other modes of oral care. PMID:27867678

Reduced Dental Plaque Formation in Dogs Drinking a Solution Containing Natural Antimicrobial Herbal Enzymes and Organic Matcha Green Tea.

PubMed

Lindinger, Michael I

2016-01-01

The results of an exploratory, multicenter clinical study confirmed the hypothesis that a novel, natural, and safe oral care product (OCP) reduced the rate of plaque formation on teeth of dogs consuming the OCP (antimicrobial plant-derived enzymes, organic matcha green tea, cultured dextrose, sodium bicarbonate, and ascorbic acid) compared to controls. Healthy dogs without periodontitis, of varying breeds, sex, and age, were recruited and enrolled, using nonrandomized stratification methods, into a control and treatment groups. Treatment group dogs drank only water into which OCP was suspended, for 28 days. Control group dogs drank their normal household water. On day 0 all teeth were cleaned by a veterinarian and gingivitis was assessed. On days 14, 21, and 28 plaque index, plaque thickness, gingivitis, freshness of breath, and general health were assessed. Over the 28 days of study, dogs on the OCP had significant reduction in plaque index and plaque thickness compared to controls. By day 14 OCP reduced plaque formation by 37%; the 28-day reduction in plaque index and coverage averaged 22% with no measurable gingivitis or calculus. Conclusion . Using the OCP attenuated dental plaque formation when consumed as normal drinking water and in the absence of other modes of oral care.

Dielectric property of NiTiO{sub 3} doped substituted ortho-chloropolyaniline composites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lakshmi, Mohana; Faisal, Muhammad; Roy, Aashish S.

2013-11-15

Ortho-chloropolyaniline (OCP)-NiTiO{sub 3} composites have been synthesized via in-situ polymerization of ortho-chloroaniline with various weight percentages of NiTiO{sub 3.} Fourier Transform Infrared spectroscopic studies of Ortho-chloropolyaniline and its composites indicated the formation of composites as a result of Vander Waal's interaction between OCP and NiTiO{sub 3} particles. Surface morphology of OCP and OCP-NiTiO{sub 3} composites were studied using Scanning Electron Microscope (SEM). The SEM micrographs indicated a modified morphology after the composite formation. Dielectric properties and electric modulus of OCP and OCP-NiTiO{sub 3} composites have been investigated in the frequency range of 50 Hz – 5 MHz. It has beenmore » noticed that electrical resistance decreases with increase in weight percentage of NiTiO{sub 3} particles in polymer matrix as well as with applied frequency. The display of semicircular arcs in Cole-Cole plots indicates the formation of series resistor and capacitor in network causing a decrease in the relaxation time and as a result conductivity enhances in these composites. The facile and cost effective synthesis process and excellent dielectric and conductivity response of these materials makes them promising materials for practical applications.« less

Dielectric property of NiTiO{sub 3} doped substituted ortho-chloropolyaniline composites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lakshmi, Mohana; Faisal, Muhammad; Roy, Aashish S.

Ortho-chloropolyaniline (OCP)-NiTiO{sub 3} composites have been synthesized via in-situ polymerization of ortho-chloroaniline with various weight percentages of NiTiO{sub 3.} Fourier Transform Infrared spectroscopic studies of Ortho-chloropolyaniline and its composites indicated the formation of composites as a result of Vander Waal's interaction between OCP and NiTiO{sub 3} particles. Surface morphology of OCP and OCP-NiTiO{sub 3} composites were studied using Scanning Electron Microscope (SEM). The SEM micrographs indicated a modified morphology after the composite formation. Dielectric properties and electric modulus of OCP and OCP-NiTiO{sub 3} composites have been investigated in the frequency range of 50 Hz – 5 MHz. It has beenmore » noticed that electrical resistance decreases with increase in weight percentage of NiTiO{sub 3} particles in polymer matrix as well as with applied frequency. The display of semicircular arcs in Cole-Cole plots indicates the formation of series resistor and capacitor in network causing a decrease in the relaxation time and as a result conductivity enhances in these composites. The facile and cost effective synthesis process and excellent dielectric and conductivity response of these materials makes them promising materials for practical applications.« less

Organochlorine Pesticides (OCPs) in raft mussels coming from Galician rías.

PubMed

Carro, Nieves; García, Isabel; Ignacio, María; Mouteira, Ana

2017-09-01

This survey gives an overview of the range of organochlorine pesticides (OCPs) α and γ-HCH (lindane), HCB, pp´-DDE, pp´-DDD, op´-DDT, pp´-DDT, aldrin, dieldrin, endrin, isodrin and trans-nonachlor in raft mussels cultivated in several polygons of the Galician Rías (Ares-Betanzos, Muros-Noia, Arousa, Pontevedra and Vigo) during the period 1998-2014. A significant number of OCPs were detected, but the levels found were generally low, mainly in the recent samplings (2010-2014). The levels of ∑DDs (sum of DDTs and its metabolites, pp´-DDE and pp´-DDD) ranged between 0.22 ng/g dry weight (dw) in samples from the Ría of Pontevedra and 46.4 ng/g dw in mussels from the Ría of Arousa. Both aldrin and endrin were not detected or were below the analytical limits of detection. With regard to other pesticides, dieldrin is the major compound, followed by γ-HCH, isodrin, α-HCH and transnonachlor. Significant ANOVA regressions indicated variations in levels of some OCPs with the biological parameters (lipid, condition index and shell length). Univariate and multivariate analysis of OCP levels revealed no significant differences between Rías. Temporal trends showed an important decline of OCPs in the studied samples during the period 1998-2014.

Design and preparation of open circuit potential biosensor for in vitro and in vivo glucose monitoring.

PubMed

Song, Yonggui; Su, Dan; Shen, Yuan; Liu, Hongyu; Wang, Li

2017-01-01

A novel open circuit potential biosensor (OCPS) composed of a working electrode and a Ag/AgCl reference electrode was designed for in vivo continuous glucose monitoring in this work. The macroporous carbon derived from kenaf stem (KSC) was used to construct a KSC microelectrode (denoted as KSCME) which was subsequently used to load glucose oxidase (GOD) as the working electrode. The resulting GOD/KSCMEs could catalyze the oxidation of glucose directly to result in changes of the open circuit potential (V oc ) of the OCPS. The V oc of OCPS was dependent on the glucose concentration, showing a linear range of 0.03-10.0 mM (R = 0.999) with a detection limit of 10 μM. In addition, the OCPS exhibited good selectivity for glucose over other common endogenous interferences. The feasibility of the proposed OCPS for glucose detection in mice skin tumors and normal tissue homogenate samples (in vitro experiment) and rat subcutaneous glucose monitoring (in vivo experiment) was also demonstrated with satisfactory results. The biosensor represents a novel example of a superficial cancer diagnostic device, and the proposed OCPS also provides new ideas for the development of a simple and highly selective device for continuous glucose sensing.

Continuous versus cyclic oral contraceptives for the treatment of endometriosis: a systematic review.

PubMed

Zorbas, Konstantinos A; Economopoulos, Konstantinos P; Vlahos, Nikos F

2015-07-01

Recurrence of endometriosis after conservative surgery has been observed in 40-50 % of patients within the first 5 years. A variety of regimens such as combined oral contraceptives, GnRH agonists, danazol, and progestins have been used postoperatively to reduce recurrence rates. Oral contraceptives (oCP) have been used either in a cyclic or in a continuous (no pill-free interval) fashion. The purpose of this article was to summarize the existing evidence on the efficacy and patient compliance for the use of oCP in a continuous versus cyclic fashion following conservative surgery for endometriosis. A systematic search of Medline identified four eligible studies. Studies were considered eligible, if they have evaluated oCP therapy, either in a cyclic or continuous regimen, after conservative surgery for endometriosis. Specifically, studies (1) reporting on women with endometriosis who were treated postoperatively with both continuous oCP and cyclic oCP, (2) written in English, (3) with minimum 6 months duration of medical treatment, and (4) with minimum 12 months duration of follow-up were considered eligible for our systematic review. Outcome measures of these eligible studies were tabulated and then analyzed cumulatively. A purely descriptive approach was adopted concerning all variables. Postoperative use of continuous oCP was associated with a reduction in the recurrence rate of dysmenorrhea, delay in the presentation of dysmenorrhea, reduction in nonspecific pelvic pain, and reduction in the recurrence rate for endometrioma. Use of oCP in a continuous fashion following conservative surgery for endometriosis is more beneficial to cyclic use.

Understanding and exploiting the phase behavior of mixtures of oppositely charged polymers and surfactants in water.

PubMed

Piculell, Lennart

2013-08-20

Complexes of oppositely charged polymers and surfactants (OCPS) in water come in many varieties, including liquid-crystalline materials, soluble complexes, structured nanoparticles, and water-insoluble surface layers. The range of available structures and properties increases even further with the addition of other amphiphilic substances that may enter, or even dissolve, the complexes, depending on the nature of the additive. Simple operations may change the properties of OCPS systems dramatically. For instance, dilution with water can induce a phase separation in an initially stable OCPS solution. More complicated processes, involving chemical reactions, can be used to either create or disintegrate OCPS particles or surface layers. The richness of their properties has made OCPS mixtures ubiquitous in everyday household products, such as shampoos and laundry detergents, and also attractive ingredients in the design of new types of responsive particles, surfaces, and delivery agents of potential use in future applications. A challenge for the rational design of an OCPS system is, however, to obtain a good fundamental understanding of how to select molecular shapes and sizes and how to tune the hydrophobic and electrostatic interactions such that the desired properties are obtained. Recent studies of OCPS phase equilibria, using a strategy where the minimum number of components is always used to address a particular question, have brought out general rules and trends that can be used for such a rational design. Those fundamental studies are reviewed here, together with more application-oriented studies where fundamental learning has been put to use.

Distributions of organochlorine compounds in sediments from Jiulong River Estuary and adjacent Western Taiwan Strait: Implications of transport, sources and inventories.

PubMed

Wu, Yuling; Wang, Xinhong; Ya, Miaolei; Li, Yongyu; Hong, Huasheng

2016-12-01

Estuaries and coastal areas strongly influenced by terrestrial inputs resulted from anthropogenic activities. To study the distributions, origins, potential transport and burden of organochlorine compounds (OCs) from river to marginal sea, organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were investigated in surface sediments collected from a subtropical estuary (Jiulong River Estuary, JRE) and the inner shelf of adjacent Western Taiwan Strait (WTS). The concentrations of OCPs and PCBs were from 5.2 to 551.7 and 1.0-8.1 ng g -1 (dry weight), respectively. OCP concentrations in the JRE were higher than in adjacent WTS, and a decreasing trend with the ascending distance from the estuary to the open sea was observed. Concentrations of DDTs were quite high in the upper reach of the estuary, inferred from antifouling paint on fishing boats of a local shipping company. According to established sediment quality guidelines, DDTs in the JRE posed potential ecological risk. HCHs in the estuary were mainly derived from the weathered HCHs preserved in the agriculture soils via local major river runoffs. OCPs patterns showed that OCPs in the south coast of WTS were resulted from local sources via river input, while OCPs in the north coast attributed to the long-range transport derived by the Fujian-Zhejiang Coastal Current. Minor variations of PCB concentrations and homologs indicated that PCBs were not the main pollutant in the agricultural region, consistent lighter PCBs reflected industrial PCBs were transported via atmospheric deposition derived by East Asia Monsoon. Moreover, the primary distribution pattern founded for DDTs and the considerable mass inventories and burdens calculated (258.1 ng cm -2 and 10.4 tones for OCPs) that higher than Pearl River Delta and Yangtze River Delta, together suggested that the contaminated sediments in the study area may be a potential source of OCPs to the global ocean. Copyright © 2016 Elsevier Ltd. All rights reserved.

Neutrophil collagenase, gelatinase, and myeloperoxidase in tears of patients with stevens-johnson syndrome and ocular cicatricial pemphigoid.

PubMed

Arafat, Samer N; Suelves, Ana M; Spurr-Michaud, Sandra; Chodosh, James; Foster, C Stephen; Dohlman, Claes H; Gipson, Ilene K

2014-01-01

To investigate the levels of matrix metalloproteinases (MMPs), myeloperoxidase (MPO), and tissue inhibitor of metalloproteinase-1 (TIMP-1) in tears of patients with Stevens-Johnson syndrome (SJS) and ocular cicatricial pemphigoid (OCP). Prospective, noninterventional cohort study. Four SJS patients (7 eyes), 19 OCP patients (37 eyes), and 20 healthy controls who underwent phacoemulsification (40 eyes). Tear washes were collected from all patients and were analyzed for levels of MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-12, MPO, and TIMP-1 using multianalyte bead-based enzyme-linked immunosorbent assays. Total MMP activity was determined using a fluorometric assay. Correlation studies were performed between the various analytes within study groups. Levels of MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-12, MPO, and TIMP-1 (in nanograms per microgram of protein) and total MMP activity (in relative fluorescent units per minute per microgram of protein) in tears; MMP-8-to-TIMP-1 ratio; MMP-9-to-TIMP-1 ratio; and the correlations between MMP-8 and MMP-9 and both MMP and MPO. MMP-8, MMP-9, and MPO levels were elevated significantly in SJS and OCP tears (SJS>OCP) when compared with controls. The MMP activity was highest in SJS patients, whereas OCP patients and controls showed lower and similar activities. The TIMP-1 levels were decreased in SJS and OCP patients when compared with those in controls, with levels in OCP patients reaching significance. The MMP-8-to-TIMP-1 and MMP-9-to-TIMP-1 ratios were markedly elevated in SJS and OCP tears (SJS>OCP) when compared with those of controls. Across all study groups, MMP-9 levels correlated strongly with MMP-8 and MPO levels, and MMP-8 correlated with MPO, but it did not reach significance in SJS patients. There was no relationship between MMP-7 and MPO. Because MMP-8 and MPO are produced by inflammatory cells, particularly neutrophils, the correlation data indicate that they may be the common source of elevated enzymes, including MMP-9, in SJS and OCP tears. Elevated MMP-to-TIMP ratios and MMP activity suggest an imbalance in tear MMP regulation that may explain the predisposition of these patients to demonstrate corneal melting and chronic complications associated with persistent inflammation. Myeloperoxidase in tears may be a sensitive and specific marker for the quantification of ocular inflammation. Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Accounting for water levels and black carbon-inclusive sediment-water partitioning of organochlorines in Lesser Himalaya, Pakistan using two-carbon model.

PubMed

Ali, Usman; Sweetman, Andrew James; Jones, Kevin C; Malik, Riffat Naseem

2018-06-18

This study was designed to monitor organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in riverine water of Lesser Himalaya along the altitude. Further, the sediment-water partitioning employing organic carbon and black carbon models were assessed. Results revealed higher water levels of organochlorine pesticides (0.07-41.4 ng L -1 ) and polychlorinated biphenyls (0.671-84.5 ng L -1 ) in Lesser Himalayan Region (LHR) of Pakistan. Spatially, elevated levels were observed in the altitudinal zone (737-975 masl) which is influenced by anthropogenic and industrial activities. Sediment-water partitioning of OCPs and PCBs were deduced using field data by employing one-carbon (f OC K OC ) and two-carbon Freundlich models (f OC K OC + f BC K BC C W nF-1 ). Results suggested improved measured vs predicted model concentrations when black carbon was induced in the model and suggested adsorption to be the dominant mechanism in phase partitioning of organochlorines in LHR.

Levels and distribution of dissolved hydrophobic organic contaminants in the Morava river in Zlín district, Czech Republic as derived from their accumulation in silicone rubber passive samplers.

PubMed

Prokeš, Roman; Vrana, Branislav; Klánová, Jana

2012-07-01

Dissolved waterborne polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were assessed over a period of one year at five sampling sites in a model industrial region in the Czech Republic using silicone rubber passive samplers. The spatial variability of POPs in the studied region in water was small and diffusive pollution sources predominate. Concentrations of the most volatile PAHs decreased with increasing water temperature in the whole region, which reflects the seasonality in atmospheric deposition. The dissolved concentrations of more hydrophobic PAHs, PCBs and OCPs in and downstream the industrial zone are related to desorption from suspended particles. Upstream the industrial area, a positive correlation of dissolved and particle-bound contamination was observed only for DDT metabolites and hexachlorobenzene. Calculated fugacities in water and bottom sediment indicated a fair degree of equilibrium between these compartments for OCPs and PCBs, whereas sediment represented a potential source of PAHs. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effect of handling characteristics on minimum time cornering with torque vectoring

NASA Astrophysics Data System (ADS)

Smith, E. N.; Velenis, E.; Tavernini, D.; Cao, D.

2018-02-01

In this paper, the effect of both passive and actively-modified vehicle handling characteristics on minimum time manoeuvring for vehicles with 4-wheel torque vectoring (TV) capability is studied. First, a baseline optimal TV strategy is sought, independent of any causal control law. An optimal control problem (OCP) is initially formulated considering 4 independent wheel torque inputs, together with the steering angle rate, as the control variables. Using this formulation, the performance benefit using TV against an electric drive train with a fixed torque distribution, is demonstrated. The sensitivity of TV-controlled manoeuvre time to the passive understeer gradient of the vehicle is then studied. A second formulation of the OCP is introduced where a closed-loop TV controller is incorporated into the system dynamics of the OCP. This formulation allows the effect of actively modifying a vehicle's handling characteristic via TV on its minimum time cornering performance of the vehicle to be assessed. In particular, the effect of the target understeer gradient as the key tuning parameter of the literature-standard steady-state linear single-track model yaw rate reference is analysed.

Composites Based on Conducting Polymers and Carbon Nanomaterials for Heavy Metal Ion Sensing (Review).

PubMed

Deshmukh, Megha A; Shirsat, Mahendra D; Ramanaviciene, Almira; Ramanavicius, Arunas

2018-07-04

Current review signifies recent trends and challenges in the development of electrochemical sensors based on organic conducting polymers (OCPs), carbon nanotubes (CNTs) and their composites for the determination of trace heavy metal ions in water are reviewed. OCPs and CNTs have some suitable properties, such as good electrical, mechanical, chemical and structural properties as well as environmental stability, etc. However, some of these materials still have significant limitations toward selective and sensitive detection of trace heavy metal ions. To overcome the limitations of these individual materials, OCPs/CNTs composites were developed. Application of OCPs/CNTs composite and their novel properties for the adsorption and detection of heavy metal ions outlined and discussed in this review.

Evaluation of enhanced soil washing process and phytoremediation with maize oil, carboxymethyl-β-cyclodextrin, and vetiver grass for the recovery of organochlorine pesticides and heavy metals from a pesticide factory site.

PubMed

Ye, Mao; Sun, Mingming; Liu, Zongtang; Ni, Ni; Chen, Yinwen; Gu, Chengang; Kengara, Fredrick Orori; Li, Huixin; Jiang, Xin

2014-08-01

An innovative ex situ soil washing technology was developed in this study to remediate organochlorine pesticides (OCPs) and heavy metals in a mixed contaminated site. Elevated temperature (60 °C) combined with ultrasonication (40 kHz, 20 min) at 50 mL L(-1) maize oil and 45 g L(-1) carboxylmethyl-β-cyclodextrin were effective in extracting pollutants from the soil. After two successive washing cycles, the removal efficiency rates for total OCPs, mirex, endosulfans, chlordanes, Cd, and Pb were approximately 94.7%, 87.2%, 98.5%, 92.3%, 91.6%, and 87.3%, respectively. Cultivation of vetiver grass and addition of nutrients for 3 months further degraded 34.7% of the residual total OCPs and partially restored the microbiological functions of the soil. This result was indicated by the significant increase in the number, biomass C, N, and functioning diversity of soil microorganisms (p < 0.05). After the treatment, the residual OCPs and heavy metals existed as very slowly desorbing fraction and residual fraction, as evaluated by Tenax extraction combined with a first-three-compartment model and sequential extraction. Moreover, the secondary environmental risk of residual pollutants in the remediated soil was at an acceptable level. The proposed combined cleanup strategy proved to be effective and environmentally friendly. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparison of the uptake of polycyclic aromatic hydrocarbons and organochlorine pesticides by semipermeable membrane devices and caged fish (Carassius carassius) in Taihu Lake, China

USGS Publications Warehouse

Ke, R.; Xu, Y.; Huang, S.; Wang, Z.; Huckins, J.N.

2007-01-01

Uptake of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) by triolein-containing semipermeable membrane devices (SPMDs) and by crucian carp (Carassius carassius) was studied in Taihu Lake, a shallow, freshwater lake in China. Crucian carp and SPMDs were deployed side by side for 32 d. The first-order uptake rate constants of individual PAHs and OCPs for the two matrices were calculated and compared to relate the amounts of chemicals accumulated by the matrices to dissolved water concentrations. On a wet-weight basis, total concentrations of PAHs and OCPs in crucian carp fillets averaged 49.5 and 13.6 ng/g, respectively, after the 32-d exposure, whereas concentrations in whole SPMDs averaged 716.9 and 62.3 ng/g, respectively. The uptake rate constants of PAHs and OCPs by SPMDs averaged seven- and fivefold higher, respectively, than those for crucian carp; however, the patterns of uptake rate constants derived from test chemical concentrations in the crucian carp and SPMDs were similar. Although equilibrium was not reached for some PAHs and OCPs during the 32-d exposure period, a reasonably good correlation between the concentration factors (CFs) and octanol/water partition coefficient (K ow) values of PAHs and OCPs in SPMDs (r = 0.86, p < 0.001) was observed when potential sorption to dissolved organic carbon was taken into account. Similar efforts to correlate the CFs and Kow values of PAHs and OCPs in crucian carp (r = 0.75, p < 0.001) were less successful, likely because of PAH metabolism by finfish. Overall, the present results suggest that SPMDs may serve as a surrogate for contaminant monitoring with fish in freshwater lake environments. ?? 2007 SETAC.

Effect of oral contraceptives and/or metformin on GLP-1 secretion and reactive hypoglycaemia in polycystic ovary syndrome.

PubMed

Glintborg, Dorte; Mumm, Hanne; Holst, Jens Juul; Andersen, Marianne

2017-05-01

Insulin resistance in polycystic ovary syndrome (PCOS) may increase the risk of reactive hypoglycaemia (RH) and decrease glucagon-like peptide-1 (GLP-1) secretion. The possible effects of treatment with oral contraceptives (OCP) and/or metformin on GLP-1 secretion and risk of RH in PCOS is undetermined. Outpatient clinic. Randomized, controlled clinical trial. Ninety women with PCOS were randomized to 12-month treatment with OCP (150 mg desogestrel + 30 mg ethinylestradiol), metformin (2 g/day) or metformin + OCP. Five-hour oral glucose tolerance tests (5-h OGTT) measuring fasting and area under the curve (AUC) for GLP-1, glucose, insulin and C-peptide were performed before and after the intervention period. Sixty-five women completed the study and 34 weight-matched healthy women were included as controls. Changes in GLP-1, glucose, insulin and C-peptide during 5-h OGTT. Fasting GLP-1 levels increased during metformin + OCP vs OCP treatment, whereas AUC GLP-1 levels were unchanged during medical treatment. The prevalence of reactive hypoglycemia increased from 9/65 to 14/65 after intervention ( P  < 0.01) and was more common after treatment with metformin + OCP (increase from 3/23 to 6/23, P  = 0.01). Reactive hypoglycaemia was associated with higher insulin and C-peptide levels during 5-h OGTT, but was unassociated with BMI and AUC GLP-1. GLP-1 levels were comparable in PCOS vs controls. AUC GLP-1 levels were significantly lower in obese vs lean patients and were inversely associated with BMI. AUC GLP-1 levels were unchanged during treatment. Increased risk of hypoglycemia during metformin + OCP could be associated with increased insulin secretion. © 2017 The authors.

Organochloride pesticides induced hepatic ABCG5/G8 expression and lipogenesis in Chinese patients with gallstone disease

PubMed Central

Ji, Guixiang; Xu, Cheng; Sun, Haidong; Liu, Qian; Hu, Hai; Gu, Aihua; Jiang, Zhao-Yan

2016-01-01

Background Organochlorine pesticides (OCPs) are one kind of persistent organic pollutants. Although they are reported to be associated with metabolic disorders, the underlying mechanism is unclear. We explored the association of OCPs with gallstone disease and its influence on hepatic lipid metabolism. Materials and Methods OCPs levels in omentum adipose tissues from patients with and without gallstone disease between 2008 and 2011 were measured by GC-MS. Differences of gene expression involved in hepatic lipid metabolism and hepatic lipids content were compared in liver biopsies between groups with high and low level of OCPs. Using HepG2 cell lines, the influence on hepatic lipid metabolism by individual OCP was evaluated in vitro. Results In all patients who were from non-occupational population, there were high levels of β-hexachlorocyclohexane (β-HCH) and p',p'-dichloroethylene (p',p'-DDE) accumulated in adipose tissues. Both β-HCH and p', p'-DDE levels were significantly higher in adipose tissues from patients with gallstone disease (294.3± 313.5 and 2222± 2279 ng/g of lipid) than gallstone-free controls (282.7± 449.0 and 2025±2664 ng/g of lipid, P< 0.01) and they were strongly related with gallstone disease (P for trend = 0.0004 and 0.0138). Furthermore, higher OCPs in adipose tissue led to increase in the expression of hepatic cholesterol transporters ABCG5 and G8 (+34% and +27%, P< 0.01) and higher cholesterol saturation index in gallbladder bile, and induced hepatic fatty acids synthesis, which was further confirmed in HepG2 cells. Conclusion OCPs might enhance hepatic secretion of cholesterol into bile via ABCG5/G8 which promoting gallstone disease as well as lipogenesis. PMID:27203212

Monitoring of organochlorine pesticides in blood of women with uterine cervix cancer.

PubMed

Polanco Rodríguez, Ángel G; Riba López, M Inmaculada; DelValls Casillas, T Ángel; Araujo León, J Alfredo; Mahjoub, Olfa; Prusty, Anjan Kumar

2017-01-01

In Yucatan, Mexico, chronic exposure of Mayan population to pesticides is expected as about 30 per cent are drinking polluted water. Residues of organochlorine pesticides (OCP) were monitored in 18 municipalities of Yucatan with high mortality rates due to uterine cervix cancer. 70 blood samples collected from Mayan women living in livestock, agricultural and metropolitan area were analyzed for OCP. Solid Phase Extraction was performed on C18 cartridges and analyzed by Gas Chromatography with Electron Capture Detector. The results showed that the highest OCP levels were detected in blood of women living in the livestock area. OCP detected were endosulfan I (7.35 μg/mL), aldrin (3.69 μg/mL), 4,4' DDD (2.33 μg/mL), 1.39 and 1.46 μg/mL of δ-HCH. Women from the agricultural area had high concentrations of OCP in their blood, particularly dieldrin (1.19 μg/mL), and 1.26 μg/mL of 4,4' DDE. In the metropolitan area, 0.080 μg/mL of γ-HCH and 0.064 μg/mL of heptachlore were detected. This monitoring study was also based on epidemiological data of uterine cervical cancer. It was found that environmental factors may have facilitated the infiltration of OCP to the aquifer used for potable water supply. These factors in addition to poverty can have impacts on public health. This first exploratory study suggests that monitoring of OCP in human is important for the establishment of health promotion programs. The integrative analysis of both, environmental and social factors would be helpful to characterize the bioaccumulation of pesticides in humans. Copyright © 2016 Elsevier Ltd. All rights reserved.

The effect of oral contraceptives on current wheezing in young women.

PubMed

Erkoçoğlu, M; Kaya, A; Azkur, D; Özyer, Ş; Özcan, C; Beşli, M; Civelek, E; Kocabaş, C N

2013-01-01

Emerging evidence suggests that sex steroid hormones may influence respiratory symptoms. The existing literature about the role of oral contraceptive pill (OCP) on respiratory disease is scarce and conflicting especially during the adolescent period. In this study, we aimed to investigate the effect of OCPs on current wheezing among adolescents and young adults. A questionnaire was administered face-to-face to adolescents and young women by a physician. The questionnaire included ISAAC survey-comprised questions on ever wheezing, current wheezing, allergic diseases, smoking history (active or passive), and family history of allergic diseases and questions on OCP usage status. The effect of OCPs on wheezing was evaluated by logistic regression analysis. A total of 487 subjects aged between 11.3 and 25.6years participated in the study and 196 (40.2%) reported that they had used OCPs. 7.4% of the participants had physician-diagnosed asthma and 10.3% of them were active smokers. It was detected that OCPs were associated with increased risk for current wheezing (odds ratio, 2.36; 95% CI, 1.25-4.47 adjusted for asthma and current smoker) and this risk was related with the usage during the past year. Young women taking oral contraceptives had a higher rate of current wheezing, suggesting that sex steroids may be of importance for respiratory health. Copyright © 2011 SEICAP. Published by Elsevier Espana. All rights reserved.

Determinants of oral contraceptive pill use and its discontinuation among rural women in Bangladesh

PubMed Central

HUMBLE, MORAG ELIZABETH

2006-01-01

Oral contraceptive pills (OCP) contribute a major share in the current method‐mix in Bangladesh. However, multiple studies show high discontinuation rates of OCP. The present study examines the behavior and attitude towards OCP use, and investigates the determinants of its discontinuation among the rural married women of Bangladesh. The present study is based on critical analyses of the data from 24 focus group discussions and 135 in‐depth‐interviews with women, their husbands and key informants conducted over the period of 1 year. The present study shows that more than two‐thirds of married women have at one time or another used OCP as a method of family planning. However, many women did not take the pills regularly and about one‐quarter of ever users had taken, at one stage or another, a ‘short break’ from OCP use. Although nearly half of them took a break because of side effects, interestingly, 16% took a break as the result of fear of health problems that were related to ‘folk stories’ and other misconceptions. The individual assessment by users of the national family planning service delivery, perceived side effects, misconceptions about continuous use of pills, quality of counseling and information, and contraceptive behavior of the OCP users considerably influenced the decisions on contraceptive use or non‐use. (Reprod Med Biol 2006; 5: 111–121) PMID:29699243

Determination of organochlorine pesticide concentrations in flathead mullet (Mugil cephalus) caught from the western Black Sea coast of Turkey.

PubMed

Bozcaarmutlu, Azra; Turna, Sema; Sapmaz, Canan; Yenisoy-Karakaş, Serpil

2014-12-01

The objective of this study was to determine the levels of 14 organochlorine pesticides (OCPs) in flathead mullet (Mugil cephalus) caught from the western Black Sea coast of Turkey. The fish samples were caught from five different locations of the western Black Sea coast of Turkey in August 2009. Organochlorine pesticides were extracted from the liver tissues, and then the levels of OCPs were measured using gas chromatography with an electron capture detector. Organochlorine pesticides were detected in all locations. The levels of total OCPs in fish samples ranged between 0.224 and 1.103 μg g(-1) dry weight in the western Black Sea coast of Turkey. DDT, beta-HCH, and endosulfan I were the dominant OCPs in the fish samples. The levels of DDT in fish samples ranged between 0.081 and 0.186 μg g(-1) dry weight. The levels of total HCH in fish samples ranged between 0.007 and 0.376 μg g(-1) dry weight in the western Black Sea coast of Turkey. Although the usage of OCPs was banned in Turkey, the results of this study clearly indicated the presence of OCPs in the western Black Sea coast of Turkey and exposure of living organisms to these chemicals.

Investigation of Shear-Thinning Behavior on Film Thickness and Friction Coefficient of Polyalphaolefin Base Fluids With Varying Olefin Copolymer Content

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zolper, Thomas J.; He, Yifeng; Delferro, Massimiliano

2016-08-11

This study investigates the rheological properties, elastohydrodynamic (EHD) film-forming capability, and friction coefficients of low molecular mass poly-alpha-olefin (PAO) base stocks with varying contents of high molecular mass olefin copolymers (OCPs) to assess their shear stability and their potential for energy-efficient lubrication. Several PAO-OCP mixtures were blended in order to examine the relationship between their additive content and tribological performance. Gel permeation chromatography (GPC) and nuclear magnetic resonance (NMR) spectroscopy were used to characterize the molecular masses and structures, respectively. Density, viscosity, EHD film thickness, and friction were measured at 303 K, 348 K, and 398 K. Film thickness andmore » friction were studied at entrainment speeds relevant to the boundary, mixed, and full-film lubrication regimes. The PAO-OCP mixtures underwent temporary shear-thinning resulting in decreases in film thickness and hydrodynamic friction. These results demonstrate that the shear characteristics of PAO-OCP mixtures can be tuned with the OCP content and provide insight into the effects of additives on EHD characteristics.« less

A combined oral contraceptive containing 30 mcg ethinyl estradiol and 3.0 mg drospirenone does not impair endothelium-dependent vasodilation

PubMed Central

Meendering, Jessica R.; Torgrimson, Britta N.; Miller, Nicole P.; Kaplan, Paul F.; Minson, Christopher T.

2010-01-01

Background Ethinyl estradiol (EE) increases endothelium-dependent vasodilation in young women, but certain progestins paired with EE in combination OCPs have been shown to antagonize the vasodilatory effects of EE. Therefore, the purpose of this study was to investigate how endothelial function, serum biomarkers, and resting blood pressures change across an OCP cycle in women using a monophasic OCP formulation containing the progestin drospirenone. Study Design Twelve women were studied during two hormone phases of their OCP cycle; once at the end of three weeks of active pills (30 mcg EE and 3.0 mg drospirenone), and once at the end of a week of placebo pills (no exogenous hormones). Results Endothelium-dependent vasodilation was greater during the active phase compared to the placebo phase (p < 0.001). In contrast, there was no difference in endothelium-independent dilation between hormone phases. Conclusion These data suggest that the combination of 30 mcg EE and 3.0 mg drospirenone used in the active phase of this OCP increases endothelium-dependent vasodilation compared to a placebo phase. PMID:20851231

Contribution and loading estimation of organochlorine pesticides from rain and canopy throughfall to runoff in an urban environment.

PubMed

Zhang, Wei; Ye, Youbin; Tong, Yindong; Ou, Langbo; Hu, Dan; Wang, Xuejun

2011-01-30

Concentrations of OCPs in rain, canopy throughfall, and runoff water were measured in the Beijing metropolitan area during the rainy seasons from 2006 to 2007. This study was conducted to calculate the fluxes of OCPs in rain and canopy throughfall, as well as their contributions to runoff. At urban sites, the contribution of HCB and ΣHCHs from rainfall accounted for approximately 50% of the mass in runoff. At the site with significant coverage of landscaping trees, the HCB, ΣHCHs, and ΣDDTs from the net canopy throughfall accounted for approximately 10% of the mass in the runoff. Based on the data obtained in this study, loadings of OCPs (in μg) in rain, net canopy throughfall, and runoff water were calculated. The input of OCPs from rain and canopy throughfall water accounted for a significant portion of urban runoff. In cities undergoing rapid urban sprawl, monitoring and control of the transport of OCPs in urban runoff are essential for effective control of environmental hazards in surface water bodies. Copyright © 2010 Elsevier B.V. All rights reserved.

A combined oral contraceptive containing 30 mcg ethinyl estradiol and 3.0 mg drospirenone does not impair endothelium-dependent vasodilation.

PubMed

Meendering, Jessica R; Torgrimson, Britta N; Miller, Nicole P; Kaplan, Paul F; Minson, Christopher T

2010-10-01

Ethinyl estradiol (EE) increases endothelium-dependent vasodilation in young women, but certain progestins paired with EE in combination oral contraceptive pills (OCPs) have been shown to antagonize the vasodilatory effects of EE. Therefore, the purpose of this study was to investigate how endothelial function, serum biomarkers and resting blood pressures change across an OCP cycle in women using a monophasic OCP formulation containing the progestin drospirenone. Twelve women were studied during two hormone phases of their OCP cycle: once at the end of 3 weeks of active pills (30 mcg EE and 3.0 mg drospirenone) and once at the end of a week of placebo pills (no exogenous hormones) Endothelium-dependent vasodilation was greater during the active phase compared to the placebo phase (p<.001). In contrast, there was no difference in endothelium-independent dilation between hormone phases. These data suggest that the combination of 30 mcg EE and 3.0 mg drospirenone used in the active phase of this OCP increases endothelium-dependent vasodilation compared to a placebo phase. Copyright © 2010 Elsevier Inc. All rights reserved.

[Residual level and ecological risk assessment of OCPs and PCBs in sediments of mudflat shellfish culturing areas in Ningbo, Zhejiang Province of East China].

PubMed

Zhu, Yun-Hai; You, Zhong-Jie; Shentu, Ji-Kang; Zhong, Hui-Ying; Chai, Li-Yue

2012-06-01

GC-ECD methods were adopted to determine the residual level of OCPs (including HCHs and DDTs) and PCBs in the surface sediments collected from mudflat shellfish culturing areas in Ningbo, with the sources of the OCPs and PCBs analyzed and the ecological risks of the residual OCPs and PCBs evaluated. The residual level of OCPs was 0.80-32.40 ng X g(-1), and that of PCBs was 3.20-33.33 ng X g(-1). The HCHs mainly came from long distance atmospheric transportation and historical residues, while the DDTs had new input at some sites, possibly coming from the application of dicofol. At most sites, there existed potential ecological risks of p, p'-DDT and DDTs, with strong indications in Qiangtou and Xidian where the residual level of p, p'-DDT was higher than the effect rang median (ERM), suggesting an ecological menace to the benthos. The residual PCBs at most sites were in low level ecological risk.

Monitoring Tensile Fatigue of Superelastic NiTi Wire in Liquids by Electrochemical Potential

NASA Astrophysics Data System (ADS)

Racek, Jan; Stora, Marc; Šittner, Petr; Heller, Luděk; Kopeček, Jaromir; Petrenec, Martin

2015-06-01

Fatigue of superelastic NiTi wires was investigated by cyclic tension in simulated biofluid. The state of the surface of the fatigued NiTi wire was monitored by following the evolution of the electrochemical open circuit potential (OCP) together with macroscopic stresses and strains. The ceramic TiO2 oxide layer on the NiTi wire surface cannot withstand the large transformation strain and fractures in the first cycle. Based on the analysis of the results of in situ OCP experiments and SEM observation of cracks, it is claimed that the cycled wire surface develops mechanochemical reactions at the NiTi/liquid interface leading to cumulative generation of hydrogen, uptake of the hydrogen by the NiTi matrix, local loss of the matrix strength, crack transfer into the NiTi matrix, accelerated crack growth, and ultimately to the brittle fracture of the wire. Fatigue degradation is thus claimed to originate from the mechanochemical processes occurring at the excessively deforming surface not from the accumulation of defects due to energy dissipative bulk deformation processes. Ironically, combination of the two exciting properties of NiTi—superelasticity due to martensitic transformation and biocompatibility due to the protective TiO2 surface oxide layer—leads to excessive fatigue damage during cyclic mechanical loading in biofluids.

In vitro osteogenic cell proliferation, mineralization, and in vivo osseointegration of injection molded high-density polyethylene-based hybrid composites in rabbit animal model.

PubMed

Tripathi, Garima; Basu, Bikramjit

2014-07-01

The present work reports the biocompatibility property of injection molded HDPE-HA-Al2O3 hybrid composites. In vitro cytocompatibility results reveal that osteogenic cell viability and bone mineralization are favorably supported in a statistically significant manner on HDPE-20% HA-20% Al2O3 composite, in comparison to HDPE-40 wt.% HA or HDPE-40 wt.% Al2O3 The difference in cytocompatibility property is explained in terms of difference in substrate wettability/surface energy and importantly, both the cell proliferation at 7 days or bone mineralization at 21 days on HDPE-20% HA-20% Al2O3 composite are either comparable or better than sintered HA. The progressive healing of cylindrical femoral bone defects in rabbit animal model was assessed by implantation experiments over 1, 4 and 12 weeks. Based on the histological analysis as well as histomorphometrical evaluation, a better efficacy of HDPE-20% HA-20% Al2O3 over high-density polyethylene (HDPE) for bone regeneration and neobone formation at host bone-implant interface was established. Taken together, the present study unequivocally establishes that despite the presence of 20% Al2O3, HDPE-based hybrid composites are as biocompatible as HA in vitro or better than HDPE in vivo. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Randomized Controlled Trial of Preconception Interventions in Infertile Women With Polycystic Ovary Syndrome.

PubMed

Legro, Richard S; Dodson, William C; Kris-Etherton, Penny M; Kunselman, Allen R; Stetter, Christy M; Williams, Nancy I; Gnatuk, Carol L; Estes, Stephanie J; Fleming, Jennifer; Allison, Kelly C; Sarwer, David B; Coutifaris, Christos; Dokras, Anuja

2015-11-01

Lifestyle modification is recommended in women with polycystic ovary syndrome (PCOS) prior to conception but there are few randomized trials to support its implementation or benefit. This study aimed to determine the relative efficacy of preconception intervention on reproductive and metabolic abnormalities in overweight/obese women with PCOS. This was a randomized controlled trial of preconception and infertility treatment at Academic Health Centers in women with infertility due to PCOS, age 18-40 y and body mass index 27-42 kg/m(2). Women were randomly assigned to receive either 16 weeks of 1) continuous oral contraceptive pills (OCPs) (ethinyl estradiol 20 mcg/1 mg norethindrone acetate) ("OCP"); 2) lifestyle modification consisting of caloric restriction with meal replacements, weight loss medication (either sibutramine, or orlistat), and increased physical activity to promote a 7% weight loss ("Lifestyle"); or 3) combined treatment with both OCP and lifestyle modification ("Combined"). After preconception intervention, women underwent standardized ovulation induction with clomiphene citrate and timed intercourse for four cycles. Pregnancies were followed with trimester visits until delivery. Weight, ovulation, and live birth were measured. We consented 216 and randomly assigned 149 women (Lifestyle: n = 50; OCP: n = 49; Combined: n = 50). We achieved significant weight loss with both Lifestyle (mean weight loss, -6.2%; 95% confidence interval (CI), -7.4--5.0; and Combined (mean weight loss, -6.4%; 95% CI, -7.6--5.2) compared with baseline and OCP (both P < .001). There was a significant increase in the prevalence of metabolic syndrome at the end of preconception treatment compared with baseline within OCP (odds ratio [OR, 2.47; 95% CI, 1.42-4.27) whereas no change in metabolic syndrome was detected in the Lifestyle (OR, 1.18; 95% CI, 0.63-2.19) or Combined (OR, 0.72; 95% CI, 0.44-1.17) groups. Cumulative ovulation rates were superior after weight loss: OCP, 46%; Lifestyle, 60%; and Combined, 67% (P < .05). Live birth rates were OCP, 12%; Lifestyle, 26%; and Combined, 24% (P = .13). A preconception weight loss intervention eliminates the adverse metabolic oral contraceptive effects and, compared with oral contraceptive pretreatment, leads to higher ovulation rates.

Analytical methods for PCBs and organochlorine pesticides in environmental monitoring and surveillance: a critical appraisal

PubMed Central

Sverko, Ed

2006-01-01

Analytical methods for the analysis of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) are widely available and are the result of a vast amount of environmental analytical method development and research on persistent organic pollutants (POPs) over the past 30–40 years. This review summarizes procedures and examines new approaches for extraction, isolation, identification and quantification of individual congeners/isomers of the PCBs and OCPs. Critical to the successful application of this methodology is the collection, preparation, and storage of samples, as well as specific quality control and reporting criteria, and therefore these are also discussed. With the signing of the Stockholm convention on POPs and the development of global monitoring programs, there is an increased need for laboratories in developing countries to determine PCBs and OCPs. Thus, while this review attempts to summarize the current best practices for analysis of PCBs and OCPs, a major focus is the need for low-cost methods that can be easily implemented in developing countries. A “performance based” process is described whereby individual laboratories can adapt methods best suited to their situations. Access to modern capillary gas chromatography (GC) equipment with either electron capture or low-resolution mass spectrometry (MS) detection to separate and quantify OCP/PCBs is essential. However, screening of samples, especially in areas of known use of OCPs or PCBs, could be accomplished with bioanalytical methods such as specific commercially available enzyme-linked immunoabsorbent assays and thus this topic is also reviewed. New analytical techniques such two-dimensional GC (2D-GC) and “fast GC” using GC–ECD may be well-suited for broader use in routine PCB/OCP analysis in the near future given their relatively low costs and ability to provide high-resolution separations of PCB/OCPs. Procedures with low environmental impact (SPME, microscale, low solvent use, etc.) are increasingly being used and may be particularly suited to developing countries. Electronic supplementary material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s00216-006-0765-y and is accessible for authorized users. PMID:17047943

Concentrations of organochlorine pesticides in pooled human serum by age and gender.

PubMed

Thomas, Aleysha; Toms, Leisa-Maree Leontjew; Harden, Fiona A; Hobson, Peter; White, Nicole M; Mengersen, Kerrie L; Mueller, Jochen F

2017-04-01

Organochlorine pesticides (OCPs) have been used for many decades in Australia with cessation of selected persistent and bioaccumulative OCPs ranging from the 1970s to as recently as 2007. The specific aims of this study were to use samples representative of an Australian population to assess age and gender differences in the concentration of OCPs in human blood sera and to investigate temporal trends in these chemicals. Serum was collected from de-identified, surplus pathology samples over five time periods (2002/03, 2006/07, 2008/09, 2010/11 and 2012/13), with 183 serum pools made from 12,175 individual samples; 26 pools in 2002/03, 85 pools in 2006/07 and 24 pools each in 2008/09, 2010/11 and 2012/13. Samples were analyzed for hexachlorobenzene (HCB), β-hexachlorocyclohexane (β-HCH), γ -hexachlorocyclohexane (lindane) (γ-HCH), oxy-chlordane, trans-nonachlor, p,p'-DDE, o,p'-DDT, p,p'-DDT and Mirex. Stratification criteria included gender and age (0-4; 5-15; 16-30; 31-45; 46-60; and >60 years) with age additionally stratified by adults >16 years and children 0-4 and 5-15 years. All pools from all collection periods had detectable concentrations of OCPs with a detection frequency of >60% for HCB, β-HCH, trans-nonachlor, p,p'-DDT and p,p'-DDE. The overall OCP concentrations increased with age with the highest concentrations in the >60 years groups. Females did not have higher mean OCP concentrations than males except for HCB concentrations (p=0.0006). Temporal trends showed overall decreasing serum concentrations by collection period with the exception of an increase in OCP concentrations between 2006/07 and 2008/09. Excluding this data point, HCB decreased from year to year by 7-76%; β-HCH concentrations decreased by 14 - 38%; trans-nonachlor concentrations decreased by 10 - 65%; p,p'-DDE concentrations decreased by 6 - 52%; and p,p'-DDT concentrations decreased by 7 - 30%. The results indicate that OCP concentrations have decreased over time as is to be expected following the phase out of these chemicals in Australia. Copyright © 2017 Elsevier Inc. All rights reserved.

Novel Chryseobacterium sp. PYR2 degrades various organochlorine pesticides (OCPs) and achieves enhancing removal and complete degradation of DDT in highly contaminated soil.

PubMed

Qu, Jie; Xu, Yang; Ai, Guo-Min; Liu, Ying; Liu, Zhi-Pei

2015-09-15

Long term residues of organochlorine pesticides (OCPs) in soils are of great concerning because they seriously threaten food security and human health. This article focuses on isolation of OCP-degrading strains and their performance in bioremediation of contaminated soil under ex situ conditions. A bacterium, Chryseobacterium sp. PYR2, capable of degrading various OCPs and utilizing them as a sole carbon and energy source for growth, was isolated from OCP-contaminated soil. In culture experiments, PYR2 degraded 80-98% of hexachlorocyclohexane (HCH) or 1,1,1-trichloro-2,2-bis (4-chlorophenyl) ethane (DDT) isomers (50 mg L(-1)) in 30 days. A pilot-scale ex situ bioremediation study of highly OCP-contaminated soil augmented with PYR2 was performed. During the 45-day experimental period, DDT concentration was reduced by 80.3% in PYR2-augmented soils (35.37 mg kg(-1) to 6.97 mg kg(-1)) but by only 57.6% in control soils. Seven DDT degradation intermediates (metabolites) were detected and identified in PYR2-augmented soils: five by GC/MS: 1,1-dichloro-2,2-bis (4-chlorophenyl) ethane (DDD), 1,1-dichloro-2,2-bis (4-chlorophenyl) ethylene (DDE), 1-chloro-2,2-bis (4-chlorophenyl) ethylene (DDMU), 1-chloro-2,2-bis (4-chlorophenyl) ethane (DDMS), and dichlorobenzophenone (DBP); and two by LC/MS: 4-chlorobenzoic acid (PCBA) and 4-chlorophenylacetic acid (PCPA). Levels of metabolites were fairly stable in control soils but varied greatly with time in PYR2-augmented soils. Levels of DDD, DDMU, and DDE in PYR2-augmented soils increased from day 0 to day 30 and then decreased by day 45. A DDT biodegradation pathway is proposed based on our identification of DDT metabolites in PYR2-augmented systems. PYR2 will be useful in future studies of OCP biodegradation and in bioremediation of OCP-contaminated soils. Copyright © 2015 Elsevier Ltd. All rights reserved.

Impact of hormonal contraception and weight loss on high-density lipoprotein cholesterol efflux and lipoprotein particles in women with polycystic ovary syndrome.

PubMed

Dokras, Anuja; Playford, Martin; Kris-Etherton, Penny M; Kunselman, Allen R; Stetter, Christy M; Williams, Nancy I; Gnatuk, Carol L; Estes, Stephanie J; Sarwer, David B; Allison, Kelly C; Coutifaris, Christos; Mehta, Nehal; Legro, Richard S

2017-05-01

To study the effects of oral contraceptive pills (OCP), the first-line treatment for PCOS, on high-density lipoprotein cholesterol (HDL-C) function (reverse cholesterol efflux capacity) and lipoprotein particles measured using nuclear magnetic resonance spectroscopy in obese women. Secondary analysis of a randomized controlled trial (OWL-PCOS) of OCP or Lifestyle (intensive Lifestyle modification) or Combined (OCP + Lifestyle) treatment groups for 16 weeks. Eighty-seven overweight/obese women with PCOS at two academic centres. Change in HDL-C efflux capacity and lipoprotein particles. High-density lipoprotein cholesterol efflux capacity increased significantly at 16 weeks in the OCP group [0·11; 95% confidence interval (CI) 0·03, 0·18, P = 0·008] but not in the Lifestyle (P = 0·39) or Combined group (P = 0·18). After adjusting for HDL-C and TG levels, there was significant mean change in efflux in the Combined group (0·09; 95% CI 0·01, 0·15; P = 0·01). Change in HDL-C efflux correlated inversely with change in serum testosterone (r s = -0·21; P = 0·05). In contrast, OCP use induced an atherogenic low-density lipoprotein cholesterol (LDL-C) profile with increase in small (P = 0·006) and large LDL-particles (P = 0·002). Change in small LDL-particles correlated with change in serum testosterone (r s = -0·31, P = 0·009) and insulin sensitivity index (ISI; r s = -0·31, P = 0·02). Both Lifestyle and Combined groups did not show significant changes in the atherogenic LDL particles. Oral contraceptive pills use is associated with improved HDL-C function and a concomitant atherogenic LDL-C profile. Combination of a Lifestyle program with OCP use improved HDL-C function and mitigated adverse effects of OCP on lipoproteins. Our study provides evidence for use of OCP in overweight/obese women with PCOS when combined with Lifestyle changes. © 2017 John Wiley & Sons Ltd.

Citrate bridges between mineral platelets in bone

PubMed Central

Davies, Erika; Müller, Karin H.; Wong, Wai Ching; Pickard, Chris J.; Reid, David G.; Skepper, Jeremy N.; Duer, Melinda J.

2014-01-01

We provide evidence that citrate anions bridge between mineral platelets in bone and hypothesize that their presence acts to maintain separate platelets with disordered regions between them rather than gradual transformations into larger, more ordered blocks of mineral. To assess this hypothesis, we take as a model for a citrate bridging between layers of calcium phosphate mineral a double salt octacalcium phosphate citrate (OCP-citrate). We use a combination of multinuclear solid-state NMR spectroscopy, powder X-ray diffraction, and first principles electronic structure calculations to propose a quantitative structure for this material, in which citrate anions reside in a hydrated layer, bridging between apatitic layers. To assess the relevance of such a structure in native bone mineral, we present for the first time, to our knowledge, 17O NMR data on bone and compare them with 17O NMR data for OCP-citrate and other calcium phosphate minerals relevant to bone. The proposed structural model that we deduce from this work for bone mineral is a layered structure with thin apatitic platelets sandwiched between OCP-citrate–like hydrated layers. Such a structure can explain a number of known structural features of bone mineral: the thin, plate-like morphology of mature bone mineral crystals, the presence of significant quantities of strongly bound water molecules, and the relatively high concentration of hydrogen phosphate as well as the maintenance of a disordered region between mineral platelets. PMID:24706850

Occurrence, distribution and sources of organochlorine pesticides (OCPs) in surface sediments from the Lijiang River, a typical karst river of southwestern China.

PubMed

Zhang, Dan; Wang, Yinghui; Yu, Kefu; Li, Pingyang; Zhang, Ruijie; Xu, Yiyin

2014-11-01

The Lijiang River is a typical karst river of southwestern China. Karst-aquifer systems are more vulnerable to contamination compared to other types of aquifers. The occurrence and distribution of organochlorine pesticides (OCPs) in surface sediments from the Lijiang River were investigated to evaluate their potential ecological risks. The total concentrations of them in sediments ranged from 0.80 to 18.73 ng/g dry weight (dw) (mean 6.83 ng/g dw). The residue levels of OCPs varied in the order of HCB > HCHs > DDTs. Compositional analyses of OCPs showed that HCHs and DDTs were mainly from historical usage. The ecological risk assessment suggested that HCHs and DDTs in Lijiang River sediments may cause adverse ecological risks, particularly at sites near agricultural areas.

Phthalate esters and organochlorine pesticides in agricultural soils and vegetables from fast-growing regions: a case study from eastern China.

PubMed

Sun, Jianteng; Pan, Lili; Tsang, Daniel C W; Li, Zhiheng; Zhu, Lizhong; Li, Xiangdong

2018-01-01

The present study investigated phthalate esters (PAEs) and organochlorine pesticides (OCPs) in agricultural soils and vegetables from eastern China. The concentrations of PAEs ranged from 109 to 5560 ng/g in soils and 60.1 to 2390 ng/g in cabbages, with average concentrations of 946 and 601 ng/g, respectively. The concentrations of OCPs ranged from <0.1 to 662 ng/g in soils and <0.1 to 42.8 ng/g in cabbages, with average concentrations of 134 and 11.6 ng/g, respectively. OCPs were mainly in the 0-30 cm surface soil layers, while PAEs could infiltrate in deep soil profiles to 70-80 cm layer. Potential source analysis traced the occurrence of OCPs to both historical application and current usage, whereas building materials and agricultural plastic film were possible input sources of PAEs in the ambient environment. OCPs showed no apparent effect on soil microbial communities, whereas significant negative relationship was observed between PAEs and fungi in soils (R = -0.54, p < 0.01). Human health risk assessment data revealed marginal noncarcinogenic risks and low carcinogenic risks in these soils. Notably, PAEs posed a comparable or higher risk level compared with that of OCPs. This study suggests the need for better regulation on pollution control and management of PAE-elevated sites to protect soil quality and food safety.

Persistence with oral contraceptive pills versus metformin in women with polycystic ovary syndrome.

PubMed

Karjane, Nicole W; Cheang, Kai I; Mandolesi, Gabriela A; Stovall, Dale W

2012-06-01

We studied patient persistence with oral contraceptive pills (OCPs) compared to metformin for treatment of polycystic ovary syndrome (PCOS) in an urban university clinic population. We conducted a retrospective cohort study of women with PCOS who were treated in our specialty clinic between 2004 and 2006. All women with the diagnosis of PCOS, defined as oligomenorrhea or amenorrhea in conjunction with clinical or biochemical evidence of hyperandrogenism, with exclusion of other causes, were included in the study. We abstracted data on demographic characteristics, medical history, anthropometrical measures, desire for pregnancy, prescribed treatment, and patient report of persistence with treatment at 3, 6, and 12 months. The primary outcome measure was persistence with prescribed treatment. One hundred nineteen subjects were included in the study. Demographic and anthropometrical characteristics were similar between the groups. At 3 months, 57.1% were persistent with OCPs, and 57.8% were persistent with metformin (p=0.93). At 6 months, the percentages dropped to 38.1% with OCPs and 43.9% with metformin (p=0.46). At 12 months, only 21.7% continued with OCPs compared to 31.2% with metformin (p=0.19). Subjects were significantly more likely to be persistent with either OCPs or metformin at 3 months compared to either 6 or 12 months (p<0.01). Women with PCOS showed similar persistence rates with OCPs compared to metformin. Persistence with either treatment precipitously decreases over time and is modest at 12 months.

Influence of oral contraceptives on anthropomorphometric, endocrine, and metabolic profiles of anovulatory polycystic ovary syndrome patients.

PubMed

Mes-Krowinkel, Miranda G; Louwers, Yvonne V; Mulders, Annemarie G M G J; de Jong, Frank H; Fauser, Bart C J M; Laven, Joop S E

2014-06-01

To evaluate the influence of oral contraceptive pills (OCPs) on anthromorphometric, endocrine, and metabolic parameters in women with polycystic ovary syndrome (PCOS). Retrospective cross-sectional cohort study for the period 1993-2011. Tertiary university hospital. PCOS patients, who never, ever, or at time of screening were using OCPs were included. A total of 1,297 patients, of whom 827 were white, were included. All PCOS patients diagnosed according to the Rotterdam 2003 consensus criteria were divided into three groups: current users, (n = 76; 6% of total), ever users (n = 1,018; 78%), and never users (n = 203; 16%). Ever users were subdivided based on the OCP-free interval. None. Anthromorphometric (blood pressure, cycle duration) and ultrasound (follicle count, mean ovarian volume) parameters, endocrine (SHBG, testosterone, free androgen index, antimüllerian hormone [AMH]) and lipid profiles. Current users and ever users were compared with never users. In current users, SHBG was increased and androgen levels decreased. Patients with an OCP-free interval of <1 year had a higher mean follicle count, higher AMH level, and increased serum androgen level compared with never users. SHBG levels remained increased until 5-10 years after cessation of OCP use. OCP use causes a milder phenotypic presentation of PCOS regarding hyperandrogenism. However, it does not alter parameters associated with increased health risks. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Risk assessment of bioaccessible organochlorine pesticides exposure via indoor and outdoor dust

NASA Astrophysics Data System (ADS)

Wang, Wei; Huang, Min-Juan; Wu, Fu-Yong; Kang, Yuan; Wang, Hong-Sheng; Cheung, Kwai Chung; Wong, Ming Hung

2013-10-01

Dust, enriched by dichlorodiphenyltrichloroethanes (DDTs), was defined as a new route of organochlorine pesticides (OCPs) exposure, especially for children. Chemical analyses showed the medians of ∑OCPs were 171 (outdoor) and 520 (indoor) μg kg-1 in Guangzhou (GZ) while 130 (outdoor) and 115 (indoor) μg kg-1 in Hong Kong (HK). Significantly higher accumulative effect of OCPs occurred in the size fractions of <63 and 63-100 μm than 100-280 and 280-2000 μm, therefore 0-100 μm dust particles were used for risk evaluation. Different cytotoxic effects on human hepatocellular live carcinoma cell (HepG2) and human skin keratinocyte cell line (KERTr) were found for extracts of indoor dust and outdoor dust from different functional areas. For total exposure (dust and food), OCPs intake via dust was low for adults (accounting for 0.16-3.78% of total exposure), while for children it was high (8.16-24.4% of total exposure). Non-carcinogenic OCPs exposure via dust was safe for adults; however DDT and Dieldrin exposure for children was higher than Reference Dose (RfD). The cancer risk related to indoor dust exposure for GZ and HK was moderate, below 10-4, while 42% of residences in GZ should be of concern (10-5). However, when bioaccessible OCPs used, daily intake and health risk were found to be greatly lower than the estimates without considering bioaccessibility.

Unscheduled bleeding with continuous oral contraceptive pills: a comparison of progestin dose.

PubMed

Kaneshiro, Bliss; Edelman, Alison; Carlson, Nichole E; Nichols, Mark; Jensen, Jeffrey

2012-07-01

Although the use of continuous oral contraceptive pills (OCPs) eliminates scheduled uterine bleeding, unscheduled bleeding is common. The objective of this study was to determine whether progestin dose influences bleeding with use of continuous OCPs. This was a secondary data analysis of two other studies of continuous OCPs. Women were eligible if they were switching from a cyclic hormonal contraceptive to a continuous OCP. Women took a 20-mcg ethinyl estradiol (EE)/100-mcg levonorgestrel (LNG) pill or a 20-mcg EE/90-mcg LNG pill for 112 days. The number of bleeding/spotting days was compared between groups using a t test. Sample size was adequate to detect a difference of 8 days of bleeding/spotting over the 112 day study period (β=0.80, α=0.05). Sixty-six subjects were enrolled, 33 in each group. There were no differences in baseline characteristic, missed OCPs or side effects. There were no differences in the mean number of bleeding/spotting days in the first 84 days of the study (90 mcg LNG mean 20.8 (SE 3.6) days versus 100 mcg LNG 17.8 (SE 2.3) days, p=.48), nor was there a difference in the time to amenorrhea (p=.35). Our results do not support the use of one LNG dose over another to decrease the amount of unscheduled bleeding women experience when initiating a continuous OCP. Copyright © 2012 Elsevier Inc. All rights reserved.

A randomized controlled trial of subantimicrobial-dose doxycycline to prevent unscheduled bleeding with continuous oral contraceptive pill use.

PubMed

Kaneshiro, Bliss; Edelman, Alison; Carlson, Nichole E; Nichols, Mark; Forbes, Marci Messerle; Jensen, Jeffrey

2012-04-01

Unscheduled bleeding is the main side effect of continuous oral contraceptive pills (OCPs) and has been correlated with the up-regulation of matrix metalloprotineases (MMPs). The study objective was to determine if prophylactic administration of doxycycline (an MMP inhibitor at low subantimicrobial doses) would prevent unscheduled bleeding during the initiation of a continuous OCP. Subjects using cyclic hormonal contraceptives (combined OCPs, patch or ring) without unscheduled bleeding were switched to continuous OCPs (20 mcg ethinyl estradiol/100 mcg levonorgestrel). They were randomized to receive daily doxycycline [sustained-release subantimicrobial dose (40 mg daily)] or placebo for the first 84 days and then observed for an additional 28 days on the continuous OCP alone. The number of bleeding/spotting days and the time in days it took to achieve amenorrhea were compared using a t test. Sixty-five subjects were randomized. Although the use of doxycycline did not significantly decrease the number of mean bleeding/spotting days in the first 84 days of the study [doxycycline 14.75 (SE 2.30), placebo 17.78 (2.31), p=.36], women who received doxycycline had a significantly earlier onset of amenorrhea [mean last day of bleeding/spotting doxycycline 61.7 (7.7), placebo 85.2 (6.7), p=.03]. The coadministration of subantimicrobial-dose doxycycline during initiation of continuous OCPs results in a significant reduction in the length of time needed to achieve amenorrhea. Copyright © 2012 Elsevier Inc. All rights reserved.

A randomized controlled trial of subantimicrobial-dose doxycycline to prevent unscheduled bleeding with continuous oral contraceptive pill use☆

PubMed Central

Kaneshiro, Bliss; Edelman, Alison; Carlson, Nichole E.; Nichols, Mark; Forbes, Marci Messerle; Jensen, Jeffrey

2016-01-01

Background Unscheduled bleeding is the main side effect of continuous oral contraceptive pills (OCPs) and has been correlated with the up-regulation of matrix metalloprotineases (MMPs). The study objective was to determine if prophylactic administration of doxycycline (an MMP inhibitor at low subantimicrobial doses) would prevent unscheduled bleeding during the initiation of a continuous OCP. Study Design Subjects using cyclic hormonal contraceptives (combined OCPs, patch or ring) without unscheduled bleeding were switched to continuous OCPs (20 mcg ethinyl estradiol/100 mcg levonorgestrel). They were randomized to receive daily doxycycline [sustained-release subantimicrobial dose (40 mg daily)] or placebo for the first 84 days and then observed for an additional 28 days on the continuous OCP alone. The number of bleeding/spotting days and the time in days it took to achieve amenorrhea were compared using a t test. Results Sixty-five subjects were randomized. Although the use of doxycycline did not significantly decrease the number of mean bleeding/spotting days in the first 84 days of the study [doxycycline 14.75 (SE 2.30), placebo 17.78 (2.31), p=.36], women who received doxycycline had a significantly earlier onset of amenorrhea [mean last day of bleeding/spotting doxycycline 61.7 (7.7), placebo 85.2 (6.7), p=.03]. Conclusion The coadministration of subantimicrobial-dose doxycycline during initiation of continuous OCPs results in a significant reduction in the length of time needed to achieve amenorrhea. PMID:22067758

The complete influenza hemagglutinin fusion domain adopts a tight helical hairpin arrangement at the lipid:water interface.

PubMed

Lorieau, Justin L; Louis, John M; Bax, Ad

2010-06-22

All but five of the N-terminal 23 residues of the HA2 domain of the influenza virus glycoprotein hemagglutinin (HA) are strictly conserved across all 16 serotypes of HA genes. The structure and function of this HA2 fusion peptide (HAfp) continues to be the focus of extensive biophysical, computational, and functional analysis, but most of these analyses are of peptides that do not include the strictly conserved residues Trp(21)-Tyr(22)-Gly(23). The heteronuclear triple resonance NMR study reported here of full length HAfp of sero subtype H1, solubilized in dodecylphosphatidyl choline, reveals a remarkably tight helical hairpin structure, with its N-terminal alpha-helix (Gly(1)-Gly(12)) packed tightly against its second alpha-helix (Trp(14)-Gly(23)), with six of the seven conserved Gly residues at the interhelical interface. The seventh conserved Gly residue in position 13 adopts a positive angle, enabling the hairpin turn that links the two helices. The structure is stabilized by multiple interhelical C(alpha)H to C=O hydrogen bonds, characterized by strong interhelical H(N)-H(alpha) and H(alpha)-H(alpha) NOE contacts. Many of the previously identified mutations that make HA2 nonfusogenic are also incompatible with the tight antiparallel hairpin arrangement of the HAfp helices.(15)N relaxation analysis indicates the structure to be highly ordered on the nanosecond time scale, and NOE analysis indicates HAfp is located at the water-lipid interface, with its hydrophobic surface facing the lipid environment, and the Gly-rich side of the helix-helix interface exposed to solvent.

Quantitative analysis of organizational culture in occupational health research: a theory-based validation in 30 workplaces of the organizational culture profile instrument.

PubMed

Marchand, Alain; Haines, Victor Y; Dextras-Gauthier, Julie

2013-05-04

This study advances a measurement approach for the study of organizational culture in population-based occupational health research, and tests how different organizational culture types are associated with psychological distress, depression, emotional exhaustion, and well-being. Data were collected over a sample of 1,164 employees nested in 30 workplaces. Employees completed the 26-item OCP instrument. Psychological distress was measured with the General Health Questionnaire (12-item); depression with the Beck Depression Inventory (21-item); and emotional exhaustion with five items from the Maslach Burnout Inventory general survey. Exploratory factor analysis evaluated the dimensionality of the OCP scale. Multilevel regression models estimated workplace-level variations, and the contribution of organizational culture factors to mental health and well-being after controlling for gender, age, and living with a partner. Exploratory factor analysis of OCP items revealed four factors explaining about 75% of the variance, and supported the structure of the Competing Values Framework. Factors were labeled Group, Hierarchical, Rational and Developmental. Cronbach's alphas were high (0.82-0.89). Multilevel regression analysis suggested that the four culture types varied significantly between workplaces, and correlated with mental health and well-being outcomes. The Group culture type best distinguished between workplaces and had the strongest associations with the outcomes. This study provides strong support for the use of the OCP scale for measuring organizational culture in population-based occupational health research in a way that is consistent with the Competing Values Framework. The Group organizational culture needs to be considered as a relevant factor in occupational health studies.

Study on the neotype zirconia's implant coated nanometer hydroxyapatite ceramics

NASA Astrophysics Data System (ADS)

Zhu, J. W.; Yang, D. W.

2007-07-01

In recent years, biologic ceramics is a popular material of implants and bioactive surface modification of dental implant became a research emphasis, which aims to improve bioactivity of implants materials and acquire firmer implants-bone interface. The zirconia ceramic has excellent mechanical properties and nanometer HA ceramics is a bioceramic well known for its bioactivity, therefore, nanometer HA ceramics coating on zirconia, allows combining the excellent mechanical properties of zirconia substrates with its bioactivity. This paper shows a new method for implant shape design and bioactive modification of dental implants surface. Zirconia's implant substrate was prepared by sintered method, central and lateral tunnels were drilled in the zirconia hollow porous cylindrical implants by laser processing. The HA powders and needle-like HA crystals were made by a wet precipitation and calcining method. Its surface was coated with nanometer HA ceramics which was used brush HA slurry and vacuum sintering. Mechanical testing results revealed that the attachment strength of nanometer HA ceramics coated zirconia samples is high. SEM and interface observation after inserted experiment indicated that calcium and phosphor content increased and symmetrically around coated implant-bone tissue interface. A significantly higher affinity index was demonstrated in vivo by histomorphometric evaluation in coated versus uncoated implants. SEM analysis demonstrated better bone adhesion to the material in coated implant at any situation. In addition, the hollow porous cylindrical implant coated with nanometer HA ceramics increase the interaction of bone and implant, the new bone induced into the surface of hollow porous cylindrical implant and through the most tunnels filled into central hole. The branch-like structure makes the implant and bone a body, which increased the contact area and decreased elastic ratio. Therefore, the macroscopical and microcosmic nested structure of implant coated nanometer HA ceramics had increased biocompatibility and improved the osteointegration. It endows the implants with new vital activity.

Effect of substrate preheating temperature and coating thickness on residual stress in plasma sprayed hydroxyapatite coating

NASA Astrophysics Data System (ADS)

Tang, Dapei

2015-07-01

A thermal-mechanical coupling model was developed based on thermal-elastic- plastic theory according the special process of plasma spraying Hydroxyapatite (HA) coating upon Ti-6Al-4V substrate. On the one hand, the classical Fourier transient heat conduction equation was modified by introducing the effect item of deformation on temperature, on the other hand, the Johnson-Cook model, suitable for high temperature and high strain rate conditions, was used as constitutive equation after considering temperature softening effect, strain hardening effect and strain rate reinforcement effect. Based on the above coupling model, the residual stress field within the HA coating was simulated by using finite element method (FEM). Meanwhile, the substrate preheating temperature and coating thickness on the influence of residual stress components were calculated, respectively. The failure modes of coating were also preliminary analyzed. In addition, in order to verify the reliability of calculation, the material removal measurement technique was applied to determine the residual stress of HA coating near the interface. Some important conclusions are obtained.

Phytoremediation of organochlorine pesticides: Concept, method, and recent developments.

PubMed

Singh, Tanvi; Singh, Dileep K

2017-09-02

Rapid increase in industrialization of world economy in the past century has resulted in significantly high emission of anthropogenic chemicals in the ecosystem. The organochlorine pesticides (OCPs) are a great risk to the global environment and endanger the human health due to their affinity for dispersion, transportation over long distances, and bioaccumulation in the food chain. Phytoremediation is a promising technology that aims to make use of plants and associated bacteria for the treatment of groundwater and soil polluted by these contaminants. Processes known to be involved in phytoremediation of OCPs include phytoaccumulation, rhizoremediation, and phytotransformation. Vegetation has been accounted to considerably amplify OCP elimination from soil, in contrast to non-planted soil, attributable to both, uptake within plant tissues and high microbial degradation of OCP within the root zone. Developing transgenic plants is a promising approach to enhance phytoremediation capabilities. Recent advances in the application of phytoremediation technique for OCPs, including uptake by plants and plant-microbe association in the rhizosphere for the enhanced degradation and mineralization of these pollutants, is presented in this review. Additionally, some attempts to improve this technique using transgenesis and role of certain enzymes are also discussed.

Occurrence, sources, and ecological risks of PBDEs, PCBs, OCPs, and PAHs in surface sediments of the Yangtze River Delta city cluster, China.

PubMed

Zhang, Ting; Yang, Wen-Long; Chen, She-Jun; Shi, Dian-Long; Zhao, Hu; Ding, Yi; Huang, Ye-Ru; Li, Nan; Ren, Yue; Mai, Bi-Xian

2014-08-01

Polybrominated diphenyl ethers (PBDEs), organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) in 25 surface sediments in three cities (Nantong, Wuxi, and Suzhou) in the Yangtze River Delta, eastern China were measured. The mean concentrations were 378, 45.8, 1.98, 4,002 ng/g for PBDEs, OCPs, PCBs, and PAHs, respectively. Their levels in the sediments in the three cities were generally consistent with the city industrialization. PBDEs and OCPs were markedly dominated by deca-BDE (>90 %) and DDTs (>70 %). A principle component analysis of the analytes identified three major factors suggesting different sources of the contaminants in the sediments. PBDEs and the organic carbon in the sediments have common sources from industrial activities; whereas OCPs and PCBs, correlated with the second factor, were mainly from historical sources. The third factor with loadings of PAHs is indicative of various combustion sources. Ecological risk assessment indicated that the potential highest risk is from DDTs, for which 22 sites exceed the effects range low (ERL) values and three sites exceed the effects range median (ERM) value.

Spin rotational symmetry breaking by orbital current patterns in two-leg Cu-O Hubbard ladders

NASA Astrophysics Data System (ADS)

Chudzinski, Piotr; Gabay, Marc; Giamarchi, Thierry

2010-03-01

In the weak-coupling limit, we study, as a function of doping, two-leg ladders with a unit cell containing both Cu and O atoms. For purely repulsive interactions, using bosonization and a novel RG scheme, we find that in a broad region of the phase diagram, the ground state consists of a pattern of orbital currents (OCP) defined on the top of an incommensurate density wave. The internal symmetry of the OCP is specific for the ladder structure, different than the ones suggested up to now for 2D cuprates. We focus on this OCP and look for measurable signals of its existence: we compute magnetic fields induced within the ladder and we check what kind of changes in the phase diagram one may expect due to SU(2) spin-rotational symmetry breaking. We also investigate a single impurity problem (incl. OCP): we discuss if Kondo physics is at play, and make qualitative predictions about the nature of impurity backscattering. This enables us to show the influence of SU(2) symmetry breaking on conductivity. We estimate the value of gap opened due to the OCP, give analytic expressions for correlation functions and discuss magnetic properties of a new phase.

4,4'-DDE and Endosulfan Levels in Agricultural Soils of the Çukurova Region, Mediterranean Turkey.

PubMed

Akça, Muhittin Onur; Hisatomi, Shihoko; Takemura, Manami; Harada, Naoki; Nonaka, Masanori; Sakakibara, Futa; Takagi, Kazuhiro; Turgay, Oğuz Can

2016-03-01

Mediterranean Turkey has long been at the forefront of Turkish agriculture and the use of organochlorinated pesticides (OCPs) in this area rose considerably between the 1940s and 1980s. This study aimed to determine OCP residue levels in agricultural soils collected from the Mersin and Adana Districts, Çukurova Basin in Mediterranean Turkey. Most soil samples were contaminated with one, or both, of two OCP metabolites; 4,4'-dichlorodiphenyldichloroethylene (4,4'-DDE) and endosulfan sulfate. 4,4'-DDE occurred in 27 of the 29 samples and ranged from 6 to 1090 µg kg(-1)-dry soil (ds)(-1), while six samples contained endosulfan sulfate ranging between 82 and 1226 µg kg(-1)-ds(-1). Generally, horticultural and corn-planted soils contained only 4,4'-DDE, whereas greenhouse cultivation appeared to accumulate both residues. This study indicated that 4,4'-DDE occurred above acceptable levels of risk in agricultural soils of Mersin District and further studies on the qualitative and quantitative assessment of OCPs in other agricultural regions with intensive pesticide use are necessary to fully understand the impact of OCPs on agricultural soil in Turkey.

Calcium phosphate coating on titanium using laser and plasma spray

NASA Astrophysics Data System (ADS)

Roy, Mangal

Though calcium phosphate (CaP) coated implants are commercially available, its acceptance is still not wide spread due to challenges related to weaker interfacial bonding between metal and ceramic, and low crystallinity of hydroxyapatite (HA). The objectives of this research are to improve interfacial strength, crystallinity, phase purity and bioactivity of CaP coated metallic implants for orthopaedic applications. The rationale is that forming a diffuse and gradient metal-ceramic interface will improve the interfacial strength. Moreover, reducing CaP particles exposure to high temperature during coating preparation, can lead to improvement in both crystallinity and phase purity of CaP. In this study, laser engineered net shaping (LENS(TM)) was used to coat Ti metal with CaP. LENS(TM) processing enabled generation of Ti+TCP (tricalcium phosphate) composite coating with diffused interface, that also increased the coating hardness to 1049+/-112 Hv compared to a substrate hardness of 200+/-15 Hv. In vitro bone cell-material interaction studies confirmed the bioactivity of TCP coatings. Antimicrobial properties of the TCP coatings were improved by silver (Ag) electrodeposition. Along with LENS(TM), radio frequency induction plasma spray, equipped with supersonic plasma nozzle, was used to prepare HA coatings on Ti with improved crystallinity and phase purity. The coating was made of multigrain HA particles of ˜200 nm in size, which consisted of 15--20 nm HA grains. In vitro bone cell-material interaction and in vivo rat model studies confirmed the HA coatings to be bioactive. Furthermore, incorporation of Sr2+ improved bone cell of HA coatings interaction. A combination of LENS(TM) and plasma spray was used to fabricate a compositionally graded HA coatings on Ti where the microstructure varied from pure HA at the surface to pure Ti substrate with a diffused Ti+TCP composite region in between. The plasma spray system was used to synthesize spherical HA nano powder from HA sol, where the production rate was 20 g/h, which is only 16% of the total powder produced. The effects of Sr2+ and Mg2+ doping on bone cell-CaP interaction was further studied with osteoclast cells. Mg2+ doing was found to be an effective way of controlling osteoclast differentiation.

Identification of epitopes within integrin β4 for binding of auto-antibodies in ocular cicatricial and mucous membrane pemphigoid: preliminary report.

PubMed

Rashid, Khwaja Aftab; Foster, C Stephen; Ahmed, A Razzaque

2013-11-19

To identify the epitopes on human β4 integrin to which the sera of patients with ocular cicatricial pemphigoid (OCP) and mucous membrane pemphigoid (MMP) without ocular involvement bind. Fragments of the intracellular domain of the β4 molecule were cloned, expressed, purified and peptides were synthesized. Antibodies to various fragments and peptides were produced in rabbits. Binding specificity was determined via Western blot and blocking experiments. Test sera and controls were injected into neonatal BALB/c mice for in vivo passive transfer. Sera from patients with OCP, MMP, and both OCP and MMP were bound to cloned fragments of IC3.0. Its subcloned fragments IC3.4 (1489 aa-1572 aa) and IC3.4.1 (1489 aa-1510 aa) were bound with the sera from patients with OCP only. Subcloned fragments IC3.6 (1573 aa-1822 aa) and IC3.6.1 (1689 aa-1702 aa) were bound with MMP sera only. No cross-reactivity in binding was observed. Immuno-affinity-purified sera from patients with OCP, MMP, and rabbit antibodies to IC3.0, IC3.4, IC3.4.1, IC3.6, and IC3.6.1, when injected in neonatal BALB/c mice, produced subepidermal blisters in their skin. These preliminary observations identified IC3.4.1 as the possible epitope for the binding of OCP auto-antibody and IC3.6.1 as the possible epitope for the binding of MMP auto-antibody without ocular disease. Antibodies specific to these peptides produced blisters when injected in mice. Still-unidentified epitopes may exist. These observations may enhance our understanding of the role of β4 integrin in the pathobiology of OCP and MMP. Early diagnosis may be possible if serologic tests with specificity and sensitivity can be developed.

Metformin improves endothelial function and carotid intima media thickness in patients with PCOS.

PubMed

Kaya, Mehmet Gungor; Yildirim, Sumeyra; Calapkorur, Bekir; Akpek, Mahmut; Unluhizarci, Kursad; Kelestimur, Fahrettin

2015-05-01

Oral contraceptive pills (OCP) are widely used for treating women with polycystic ovary syndrome (PCOS). Metformin has beneficial effects on insulin resistance and endothelial functions. The aim of this study was to investigate the effects of treatment with drospirenone/ethinyl estradiol (EE) alone or in combination with metformin on the flow-mediated vasodilatation (FMD) and carotid intima media thickness (CIMT) in women with PCOS. Fifty women with PCOS (mean age 23 ± 5) were randomized to oral treatment of OCP alone (n = 25) or an OCP combination with metformin (n = 25) for 6 months. FMD from the brachial artery and CIMT were calculated. The hormonal profile, HOMA-IR score, basal insulin and glucose levels were studied in both groups. Before and after 6 months' treatment, echocardiographic measurements and laboratory tests were also obtained. After 6 months' treatment we observed a small decrease in FMD in the OCP group (14.9 ± 9.4 versus 14.4 ± 9.9, p = 0.801) and a slight increase in the combination group (14.5 ± 9.1 versus 15.0 ± 8.0, p = 0.715) but neither of them reached significance. CIMT increased in the OCP group (0.048 ± 0.011 to 0.050 ± 0.010 cm, p = 0.433) and decreased slightly in the combination group (0.049 ± 0.012, 0.048 ± 0.011 cm, p = 0.833). We demonstrated that adding metformin to OCP treatment may have beneficial effect on FMD and CIMT that represent vascular function in patients with PCOS. These results suggest that adding metformin to OCP treatment for PCOS could preserve the cardiovascular system and improve it.

Concentrations, bioaccumulation, and human health risk assessment of organochlorine pesticides and heavy metals in edible fish from Wuhan, China.

PubMed

Cui, Lili; Ge, Jing; Zhu, Yindi; Yang, Yuyi; Wang, Jun

2015-10-01

The objective of this study was to determine concentration and bioaccumulation of organochlorine pesticides and heavy metals in edible fish from Wuhan, China, in order to assess health risk to the human via fish consumption. Two edible fish species (Aristichthys nobilis and Hypophthalmichthys molitrix) were collected and analyzed for 11 organochlorine pesticides (OCPs) and eight heavy metals (HMs). Concentrations of ∑HCHs, ∑DDTs, and ∑OCPs in fish samples were in the range of 0.37-111.20, not detected (nd)-123.61, and 2.04-189.04 ng g(-1) (wet weight), respectively. Bioaccumulation factors (BAFs) of OCPs in bighead carp (A. nobilis) were higher than those in silver carp (H. molitrix). Concentrations of ∑HMs in bighead carp and silver carp were 352.48 and 345.20 mg kg(-1) (dw), respectively. Daily exposure of OCPs and HMs for consumers was estimated by comparing estimated daily intake (EDI) with different criteria. The results revealed that the EDIs in our study were all lower than those criteria. Target hazard quotient (THQ) and risk ratio (R) were used to evaluate non-carcinogenic and carcinogenic risks, respectively. As regard to non-carcinogenic effects of the contaminants, hazard quotients (THQ) of OCPs and HMs were both lower than 1.0, implying negligible non-carcinogenic risk via fish consumption in study area. Nevertheless, in view of carcinogenic effects of the contaminants, the total value of risk ratio (R) of OCPs was lower than the threshold of tolerable risk while the total value of risk ratio (R) of HMs was higher than the threshold of tolerable risk due to the high carcinogenic risk ratios of As and Cr, indicating high carcinogenic risks via fish consumption. The results demonstrated that HMs in edible fish from Wuhan, China, especially As and Cr required more attention than OCPs.

Bioaccumulation and human health risk assessment of DDT and other organochlorine pesticides in an apex aquatic predator from a premier conservation area.

PubMed

Gerber, Ruan; Smit, Nico J; Van Vuren, Johan H J; Nakayama, Shouta M M; Yohannes, Yared B; Ikenaka, Yoshinori; Ishizuka, Mayumi; Wepener, Victor

2016-04-15

With the second highest gross domestic product in Africa, South Africa is known to have a high pesticide usage, including the highly persistent and banned group of organochlorine pesticides (OCPs). South Africa is also one of few countries to still actively spray DDT as malaria vector control. The aim of the study was to determine the degree to which aquatic biota in selected rivers of the world renowned Kruger National Park (KNP) are exposed to by use of OCPs in the catchments outside the KNP and how this exposure relates to human health. Tigerfish (Hydrocynus vittatus) are economically important apex predators and was selected as bioindicator for this study. Fish were sampled from the KNP sections of the Luvuvhu, Letaba and Olifants rivers during the high and low flow periods from 2010 to 2011 within the KNP and 19 OCPs were determined in muscle tissue using GC-ECD techniques. Significant flow related and spatial OCP bioaccumulation was observed. Tigerfish from the Luvuvhu River displayed the highest OCP bioaccumulation. Concentrations of the majority of the OCPs including the DDTs were the highest levels ever recorded from South African freshwater systems and in many cases the concentrations were higher than most contaminated areas from around the world. The concentrations found in H. vittatus muscle also exceeded maximum residue levels in edible fat as set by the European Union. The health risk assessment also demonstrated that the levels of OCPs pose very high cancer risks to the local populations consuming tigerfish, as high as 2 in 10 increased risk factor. This is of concern not only when managing the water resources of the conservation area but also for surrounding communities consuming freshwater fish. Contaminants enter the park from outside the borders and pose potential risks to the mandated conservation of aquatic biota within the KNP. Copyright © 2016 Elsevier B.V. All rights reserved.

Knowledge, attitude and practice of pharmacists and health-care workers regarding oral contraceptives correct usage, side-effects and contraindications.

PubMed

Sattari, M; Mokhtari, Z; Jabari, H; Mashayekhi, S O

2013-06-01

Despite the success of the Iranian family planning programme, the number of unwanted pregnancies remains high. To investigate whether health workers in Tabriz are providing correct information and counselling about OCP use, the current study was planned to examine the level of knowledge, attitude and practice of OCP providers. A sample of 150 health-care workers in health houses and 150 community/hospital pharmacists answered a questionnaire about knowledge of correct use of OCP, side-effects, contraindications, danger signs/symptoms and non-contraceptive benefits, and whether they counselled patients about these subjects. Knowledge of pharmacists and health workers was not as high as expected and in many topics they were counselling patients even when they had incorrect knowledge and in other areas they were not providing information to patients despite having the correct knowledge. Better continuing education for OCP providers and especially for pharmacists seems necessary.

Current results with slow freezing and vitrification of the human oocyte.

PubMed

Boldt, Jeffrey

2011-09-01

The past decade has witnessed renewed interest in human oocyte cryopreservation (OCP). This article reviews the two general methods used for OCP, slow freezing and vitrification, compares the outcomes associated with each technique and discusses the factors that might influence success with OCP (such as oocyte selection or day of transfer). Based on available data, OCP offers a reliable, reproducible method for preservation of the female gamete and will find increasing application in assisted reproductive technology. Oocyte cryopreservation can provide a number of advantages to couples undergoing assisted reproduction or to women interested in fertility preservation. Two methods, slow freezing and vitrification, have been used successfully for oocyte cryopreservation. This article reviews and compares these methods, and discusses various factors that can impact upon success of oocyte cryopreservation. Copyright © 2011 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Mechanical, Thermal and Acoustic Properties of Open-pore Phenolic Multi-structured Cryogel

NASA Astrophysics Data System (ADS)

Yao, Rui; Yao, Zhengjun; Zhou, Jintang; Liu, Peijiang; Lei, Yiming

2017-09-01

Open-pore phenolic cryogel acoustic multi-structured plates (OCMPs) were prepared via modified sol gel polymerization and freeze-dried methods. The pore morphology, mechanical, thermal and acoustic properties of the cryogels were investigated. From the experimental results, the cryogels exhibited a porous sandwich microstructure: A nano-micron double-pore structure was observed in the core layer of the plates, and nanosized pores were observed in the inner part of the micron pores. In addtion, compared with cryogel plates with uniform-pore (OCPs), the OCMPs had lower thermal conductivities. What’s more, the compressive and tensile strength of the OCMPs were much higher than those of OCPs. Finally, the OCMPs exhibited superior acoustic performances (20% solid content OCMPs performed the best) as compared with those of OCPs. Moreover, the sound insulation value and sound absorption bandwidth of OCMPs exhibited an improvement of approximately 3 and 2 times as compared with those of OCPs, respectively.

Guidelines for education and training at the doctoral and postdoctoral levels in consulting psychology/organizational consulting psychology.

PubMed

2007-12-01

The purpose of these "Guidelines for Education and Training at the Doctoral and Postdoctoral Levels in Consulting Psychology/Organizational Consulting Psychology" is to provide a common framework for use in the development, evaluation, and review of education and training in consulting psychology/organizational consulting psychology (CP/OCP). The intent of these guidelines is to improve the quality of teaching and learning in the area of the practice of CP, especially OCP, within the scientific discipline and profession of psychology. Towards these ends, this document is intended as guidance for psychologists who teach or plan curricula for teaching CP/OCP at doctoral or postdoctoral levels of professional education and training in psychology. The guidelines are structured in the form of overarching principles, general competencies, and domain-specific competencies that are ideally obtained by persons receiving training at the doctoral or postdoctoral level in CP/OCP. (Copyright) 2007 APA.

PHOTOSYNTHESIS. A 12 Å carotenoid translocation in a photoswitch associated with cyanobacterial photoprotection.

PubMed

Leverenz, Ryan L; Sutter, Markus; Wilson, Adjélé; Gupta, Sayan; Thurotte, Adrien; Bourcier de Carbon, Céline; Petzold, Christopher J; Ralston, Corie; Perreau, François; Kirilovsky, Diana; Kerfeld, Cheryl A

2015-06-26

Pigment-protein and pigment-pigment interactions are of fundamental importance to the light-harvesting and photoprotective functions essential to oxygenic photosynthesis. The orange carotenoid protein (OCP) functions as both a sensor of light and effector of photoprotective energy dissipation in cyanobacteria. We report the atomic-resolution structure of an active form of the OCP consisting of the N-terminal domain and a single noncovalently bound carotenoid pigment. The crystal structure, combined with additional solution-state structural data, reveals that OCP photoactivation is accompanied by a 12 angstrom translocation of the pigment within the protein and a reconfiguration of carotenoid-protein interactions. Our results identify the origin of the photochromic changes in the OCP triggered by light and reveal the structural determinants required for interaction with the light-harvesting antenna during photoprotection. Copyright © 2015, American Association for the Advancement of Science.

Assessment of osteoinduction using a porous hydroxyapatite coating prepared by micro-arc oxidation on a new titanium alloy.

PubMed

Jing, Wensen; Zhang, Minghua; Jin, Lei; Zhao, Jian; Gao, Qing; Ren, Min; Fan, Qingyu

2015-12-01

Surface modification and material improvement is now an important way to improve the osseointegration between bone and uncemented prothesis. The purpose of this study was to investigate the bone ingrowth potential of porous hydroxyapatite (HA) coatings prepared by micro-arc oxidation (MAO) on Ti-3Zr-2Sn-3Mo-25Nb, a new titanium alloy. HA-coated specimens were implanted in the left proximal femoral medullary canal of beagles for 4, 12, and 24 weeks, and uncoated specimens were implanted in the right as a control. The surface morphology and phase composition were investigated with environmental scanning electron microscopy and X-ray diffractometry. The bone ingrowth was assessed by histomorphometry. A pull-out test was performed to assess the mechanical performance of the bone-implant interface. A porous coating was well prepared on the new titanium alloy by using the MAO method. The bone-to-implant contact was significantly higher for the HA-coated group compared to that in the uncoated group. Mechanical tests showed that the HA-coated group had significantly higher maximum force at the bone-implant interface compared to the uncoated specimens. MAO is a suitable coating approach for this new titanium alloy. The HA coating prepared by this approach can significantly promote bone ingrowth and the mechanical performance of the bone-implant interface. Copyright © 2015. Published by Elsevier Ltd.

Knowledge about missed contraceptive pills among married women at King Abdulaziz University Hospital

PubMed Central

Iftikhar, Rahila; Aba Al Khail, Bahaa Abdulrahman

2015-01-01

Background Oral contraceptive pills (OCPs) are one of the most reliable methods of contraception. However, lack of knowledge about oral contraceptive use and inconsistent pill-taking might result in decreased efficacy. The study reported here aimed to explore women’s knowledge about oral contraceptive use and assess the factors associated with knowledge about OCPs among users. Methods This cross-sectional survey was conducted at King Abdulaziz University Hospital, Jeddah, Saudi Arabia between April and June 2014. We included married, non-pregnant women >18 years old who had used a combined 21-day OCP for at least 3 months prior to recruitment. A questionnaire was used to collect the participants’ demographic information. It also assessed their knowledge about OCPs. Data were entered into and analyzed using SPSS software. Results A total of 357 women were recruited. Of these, 57.7% reported they knew what to do after missing one or two pills, but only 18.3% knew exactly what to do after missing more than two pills consecutively. Postgraduate women had a significantly higher knowledge score than illiterate women (P=0.002) and those who had completed at least primary education (P=0.001). Conversely, there was no difference in knowledge scores between Saudi and expatriate women (P=0.2). Monthly incomes (P=0.2) and mode of OCP selection (P=0.2) were also not significantly associated with knowledge scores. Conclusion Women had poor knowledge about OCP use. Appropriate measures should be taken to educate women about proper oral contraceptive use. PMID:25792813

Effects of medical therapy on insulin resistance and the cardiovascular system in polycystic ovary syndrome.

PubMed

Meyer, Caroline; McGrath, Barry P; Teede, Helena Jane

2007-03-01

We aimed to determine the impact of medical therapy for symptom management on insulin resistance, metabolic profiles, and surrogate markers of cardiovascular disease in polycystic ovary syndrome (PCOS), an insulin-resistant pre-diabetes condition. One hundred overweight women (BMI >27 kg/m2), average age 31 years, who were nonsmokers, were not pregnant, did not have diabetes, and were off relevant medications for 3 months completed this 6-month open-label controlled trial. Randomization was to a control group (higher-dose oral contraceptive [OCP] 35 microg ethinyl estradiol [EE]/2 mg cyproterone acetate, metformin [1 g b.d.] or low-dose OCP [20 microg EE/100 microg levonorgestrel + aldactone 50 mg b.d.]). Primary outcome measures were insulin resistance (area under curve on oral glucose tolerance test) and surrogate markers of cardiovascular disease including arterial stiffness (pulse wave velocity [PWV]) and endothelial function. All treatments similarly and significantly improved symptoms including hirsutism and menstrual cycle length. Insulin resistance was improved by metformin and worsened by the high-dose OCP. Arterial stiffness worsened in the higher-dose OCP group (PWV 7.46 vs. 8.03 m/s, P < 0.05), related primarily to the increased insulin resistance. In overweight women with PCOS, metformin and low- and high-dose OCP preparations have similar efficacy but differential effects on insulin resistance and arterial function. These findings suggest that a low-dose OCP preparation may be preferable if contraception is needed and that metformin should be considered for symptomatic management, particularly in women with additional metabolic and cardiovascular risk factors.

Organochloride pesticides modulated gut microbiota and influenced bile acid metabolism in mice.

PubMed

Liu, Qian; Shao, Wentao; Zhang, Chunlan; Xu, Cheng; Wang, Qihan; Liu, Hui; Sun, Haidong; Jiang, Zhaoyan; Gu, Aihua

2017-07-01

Organochlorine pesticides (OCPs) can persistently accumulate in body and threaten human health. Bile acids and intestinal microbial metabolism have emerged as important signaling molecules in the host. However, knowledge on which intestinal microbiota and bile acids are modified by OCPs remains unclear. In this study, adult male C57BL/6 mice were exposed to p, p'-dichlorodiphenyldichloroethylene (p, p'-DDE) and β-hexachlorocyclohexane (β-HCH) for 8 weeks. The relative abundance and composition of various bacterial species were analyzed by 16S rRNA gene sequencing. Bile acid composition was analyzed by metabolomic analysis using UPLC-MS. The expression of genes involved in hepatic and enteric bile acids metabolism was measured by real-time PCR. Expression of genes in bile acids synthesis and transportation were measured in HepG2 cells incubated with p, p'-DDE and β-HCH. Our findings showed OCPs changed relative abundance and composition of intestinal microbiota, especially in enhanced Lactobacillus with bile salt hydrolase (BSH) activity. OCPs affected bile acid composition, enhanced hydrophobicity, decreased expression of genes on bile acid reabsorption in the terminal ileum and compensatory increased expression of genes on synthesis of bile acids in the liver. We demonstrated that chronic exposure of OCPs could impair intestinal microbiota; as a result, hepatic and enteric bile acid profiles and metabolism were influenced. The findings in this study draw our attention to the hazards of chronic OCPs exposure in modulating bile acid metabolism that might cause metabolic disorders and their potential to cause related diseases in human. Copyright © 2017 Elsevier Ltd. All rights reserved.

Spatial distributions and seasonal variations of organochlorine pesticides in water and soil samples in Bolu, Turkey.

PubMed

Karadeniz, Hatice; Yenisoy-Karakaş, Serpil

2015-03-01

In this study, a total of 75 water samples (38 groundwater and 37 surface water samples) and 54 surface soil samples were collected from the five districts of Bolu, which is located in the Western Black Sea Region of Turkey in the summer season of 2009. In the autumn season, 17 water samples (surface water and groundwater samples) and 17 soil samples were collected within the city center to observe the seasonal changes of organochlorine pesticides (OCPs). Groundwater and surface water samples were extracted using solid phase extraction. Soil samples were extracted ultrasonically. Sixteen OCP compounds in the standard solution were detected by a gas chromatography-electron capture detector (GC-ECD). Therefore, the method validation was performed for those 16 OCP compounds. However, 13 OCP compounds could be observed in the samples. The concentrations of most OCPs were higher in samples collected in the summer than those in the autumn. The most frequently observed pesticides were endosulfan sulfate and 4,4'-dichlorodiphenyltrichloroethane (DDT) in groundwater samples, α-HCH in surface water samples, and endosulfan sulfate in soil samples. The average concentration of endosulfan sulfate was the highest in water and soil samples. Compared to the literature values, the average concentrations in this study were lower values. Spatial distribution of OCPs was evaluated with the aid of contour maps for the five districts of Bolu. Generally, agricultural processes affected the water and soil quality in the region. However, non-agricultural areas were also affected by pesticides. The concentrations of pesticides were below the legal limits of European directives for each pesticide.

Mission Report on the Orbiter Camera Payload System (OCPS) Large Format Camera (LFC) and Attitude Reference System (ARS)

NASA Technical Reports Server (NTRS)

Mollberg, Bernard H.; Schardt, Bruton B.

1988-01-01

The Orbiter Camera Payload System (OCPS) is an integrated photographic system which is carried into earth orbit as a payload in the Space Transportation System (STS) Orbiter vehicle's cargo bay. The major component of the OCPS is a Large Format Camera (LFC), a precision wide-angle cartographic instrument that is capable of producing high resolution stereo photography of great geometric fidelity in multiple base-to-height (B/H) ratios. A secondary, supporting system to the LFC is the Attitude Reference System (ARS), which is a dual lens Stellar Camera Array (SCA) and camera support structure. The SCA is a 70-mm film system which is rigidly mounted to the LFC lens support structure and which, through the simultaneous acquisition of two star fields with each earth-viewing LFC frame, makes it possible to determine precisely the pointing of the LFC optical axis with reference to the earth nadir point. Other components complete the current OCPS configuration as a high precision cartographic data acquisition system. The primary design objective for the OCPS was to maximize system performance characteristics while maintaining a high level of reliability compatible with Shuttle launch conditions and the on-orbit environment. The full-up OCPS configuration was launched on a highly successful maiden voyage aboard the STS Orbiter vehicle Challenger on October 5, 1984, as a major payload aboard mission STS 41-G. This report documents the system design, the ground testing, the flight configuration, and an analysis of the results obtained during the Challenger mission STS 41-G.

The influence of coping strategies on subsequent well-being in older patients with cancer: A comparison with 2 control groups.

PubMed

Baitar, Abdelbari; Buntinx, Frank; De Burghgraeve, Tine; Deckx, Laura; Schrijvers, Dirk; Wildiers, Hans; van den Akker, Marjan

2018-03-01

To evaluate dispositional coping strategies as predictors for changes in well-being after 1 year in older patients with cancer (OCP) and 2 control groups. OCP were compared with 2 control groups: middle-aged patients with cancer (MCP) (aging effect) and older patients without cancer (ONC) (cancer effect). Patients were interviewed shortly after a cancer diagnosis and 1 year later. Dispositional coping was measured with the Short Utrecht Coping List. For well-being, we considered psychological well-being (depression, loneliness, distress) and physical health (fatigue, ADL, IADL). Logistic regression analyses were performed to study baseline coping as predictor for subsequent well-being while controlling for important baseline covariates. A total of 1245 patients were included in the analysis at baseline: 263 OCP, 590 ONC, and 392 MCP. Overall, active tackling was employed most often. With the exception of palliative reacting, OCP utilized each coping strategy less frequently than MCP. At 1-year follow-up, 833 patients (66.9%) were interviewed. Active coping strategies (active tackling and seeking social support) predicted subsequent well-being only in MCP. Avoidance coping strategies did not predict well-being in any of the patient groups. Palliative reacting predicted distress in OCP; depression and dependency for ADL in MCP. Coping strategies influence subsequent well-being in patients with cancer, but the impact is different in the age groups. Palliative reacting was the only coping strategy that predicted well-being (ie, distress) in OCP and is therefore, especially in this population, a target for coping skill interventions. Copyright © 2017 John Wiley & Sons, Ltd.

The effect of drospirenone (3 mg) with ethinyl estradiol (30 mcg) containing pills on ovarian blood flows in women with polycystic ovary syndrome: a case controlled study.

PubMed

Okyay, Emre; Gode, Funda; Acet, Ferruh; Bodur, Taylan; Cagliyan, Erkan; Sahan, Ceyda; Posaci, Cemal; Gulekli, Bulent

2014-09-01

To evaluate whether oral contraceptive pill (OCP) therapy has any effects on ovarian stromal blood flow by using pulsed and color Doppler at the end of 3 months follow-up period of OCP-users and non-users with or without polycystic ovary syndrome (PCOS). 200 patients were included in the study. The patients were designed into four groups as follows; Group 1: PCOS patients that received OCP containing 30 mcg ethinyl estradiol (EE) plus 3mg drospirenone for 3 months (DRP n=50); Group 2: PCOS patients that received no medication (n=50); Group 3: Healthy controls that received OCP (EE plus DRP) (n=50); Group 4: healthy controls that received no medication (n=50). Resistance index (RI) and pulsatility index (PI) of both ovarian arteries, hormonal, anthropometric and biochemical parameters were assessed before and after 3 months. There was a significant increament in RI and PI of both ovarian arteries in healthy controls (Group 3) and in women with PCOS (Group 1) who received OCP (p<0.001). The increment rate in both Doppler parameters were significantly higher in women with PCOS (Group 1) than healthy controls (Group 3) (p<0.001). Whereas RI and PI values of both ovaries remained unchanged in all untreated women with or without PCOS (Groups 2 and 4). OCP therapy reduced ovarian vascularization in both PCOS and healthy users after 3 months of therapy and this decrease is especially noticeable in women with PCOS. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

A piezoelectric immunosensor for the detection of alpha-fetoprotein using an interface of gold/hydroxyapatite hybrid nanomaterial.

PubMed

Ding, Yanjun; Liu, Jia; Wang, Hua; Shen, Guoli; Yu, Ruqin

2007-04-01

The ideal immobilization methods that are suitable for binding immuno-active materials with high efficiency onto the sensing surface are the key target to pursue in the current biosensor design. In this paper, a new hybrid material formed by assembling gold nanoparticles (GNP) onto nano-sized hydroxyapatite (HA) has been employed for the interface design of piezoelectric immunosensor, on which the antibodies were bound. The detection performances of the resulting immunosensor were investigated by use of the antibody-antigen model system of alpha-Fetoprotein (AFP), an important indicator in the diagnosis of clinical cancers. The hybrid material was characterized by the UV-vis spectroscopy, the SEM and TEM measurements. The frequency and electrochemical impedance responses characteristics for the processes of immobilization and immunoreaction of anchored anti-AFP antibodies were studied in detail. The immunoresponse of the proposed immunosensor was compared with those antibodies immobilized by using HA or GNP alone. It was found that the developed sensing interface has some advantages such as the activation-free immobilization and the high antigen-binding activities of antibodies. The as-prepared immunosensor can allow for the determination of AFP in the concentration range of 15.3-600.0ngml(-1). Such an interface design with the nano-sized hybrid materials should be tailored as a new alternative used for biosensor design.

Critical Role of MKP-1 in Lipopolysaccharide-Induced Osteoclast Formation through CXCL1 and CXCL2

PubMed Central

Valerio, Michael S.; Herbert, Bethany A.; Basilakos, Dimitrios S.; Browne, Courtney; Yu, Hong; Kirkwood, Keith L.

2014-01-01

Osteoclast (OC) progenitors (OCP) have been defined in the bone marrow (BM) as CD3−CD45R(B220)−GR1−CD11blo/−CD115+ (dOCP) and more recently in the peripheral blood (PB) as Lym−Ly6G−CD11b+Ly6C+. These progenitors respond to stimuli, including LPS from periopathogenic Aggregatibacter actinomycetemcomitans, activating MAPK signaling, resulting in cytokine/chemokine-mediated osteoclastogenesis. Intracellular negative signaling pathways, including MAPK phosphatase-1 (MKP-1, gene Dusp1) deactivate MAPK pathways (p-p38 and p-JNK) and reduce inflammatory cytokines/chemokines. Objective To delineate the role of MKP-1 in chemokine-mediated OC formation using defined OC progenitor populations. Given its role in innate immune inflammatory signaling, we hypothesize that MKP-1 regulates LPS-induced OC formation from BM OCP through deregulated chemokines. Methods BM and PB from WT and Dusp1−/− female mice (8–12wks) was obtained and sorted into defined progenitor populations. BM sorted dOCP were primed with MCSF and RANKL (48hrs), blocked with vehicle or chemokine blocking antibodies and stimulated with LPS (48–96hrs). TRAP assay and OC activity were measured for OC formation and activity following treatments. Nanostring Array and qPCR were utilized for gene expression analysis. Results Dusp1−/− dOCPs formed more and larger osteoclasts from CD11bhi and dOCP compared to matched WT (P<0.05 each). PB-derived dOCP produced larger and more functional osteoclasts from Dusp1−/− mice compared to WT controls. Nanostring array data revealed significant deregulation in chemokine expression from Dusp1−/− vs. WT cells. qPCR validation of target genes revealed that Dusp1 deficient CD11b+ populations display 1.5–3.5-fold greater expression of CXCL1 and 2–3-fold greater expression of CXCL2 compared to WT in CD11bhi and dOCP (P<0.05 each). Antibody blocking studies using anti-CXCL1 and CXCL2 antibodies blunted osteoclastogenesis in Dusp1−/− cells. Conclusion MKP-1 negatively regulates chemokine-driven OC formation and subsequent bone resorption in response to LPS stimulation. Collectively, these data provide useful insight into mechanisms potentially leading to the development of therapeutic treatment of periodontal disease. PMID:25261746

Organochlorine pesticide levels in Clarias gariepinus from polluted freshwater impoundments in South Africa and associated human health risks.

PubMed

Barnhoorn, I E J; van Dyk, J C; Genthe, B; Harding, W R; Wagenaar, G M; Bornman, M S

2015-02-01

There are increasing concerns regarding the safe human consumption of fish from polluted, freshwater impoundments. The aim of this study was to analyse the muscle tissue of the sharptooth catfish Clarias gariepinus for selected organo-chlorine pesticides (OCPs) and to perform a human health risk assessment using a standard protocol described by the United States Environmental Protection Agency (US EPA). Fish were collected from the polluted Roodeplaat-(RDPD), Rietvlei-(RVD) and Hartbeespoort (HBPD) Dam impoundments located in the north-eastern regions of South Africa. GC-MS analyses showed levels of various OCPs in fish muscle samples from all three impoundments. For fish collected from the RDPD, p,p'-DDE, endosulfan, lindane and β- and δ-HCH were the most prevalent OCPs detected, while p,p'-DDE and endosulfan were the most predominant in fish from the RVD. Lindane and β- and δ-HCH were the main OCPs detected in fish from the HBPD. Dieldrin was the only OCP detected at concentrations for which a cancer risk and a hazard index above the acceptable risk levels were estimated. This was the case for fish from both the RDPD and RVD impoundments. No toxic risk was estimated should fish from the HBPD be consumed. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Orbiter camera payload system's large-format camera and attitude reference system

NASA Technical Reports Server (NTRS)

Schardt, B. B.; Mollberg, B. H.

1985-01-01

The Orbiter camera payload system (OCPS) is an integrated photographic system carried into earth orbit as a payload in the Space Transportation System (STS) Orbiter vehicle's cargo bay. The major component of the OCPS is a large-format camera (LFC), a precision wide-angle cartographic instrument capable of producing high-resolution stereophotography of great geometric fidelity in multiple base-to-height ratios. A secondary and supporting system to the LFC is the attitude reference system (ARS), a dual-lens stellar camera array (SCA) and camera support structure. The SCA is a 70 mm film system that is rigidly mounted to the LFC lens support structure and, through the simultaneous acquisition of two star fields with each earth viewing LFC frame, makes it possible to precisely determine the pointing of the LFC optical axis with reference to the earth nadir point. Other components complete the current OCPS configuration as a high-precision cartographic data acquisition system. The primary design objective for the OCPS was to maximize system performance characteristics while maintaining a high level of reliability compatible with rocket launch conditions and the on-orbit environment. The full OCPS configuration was launched on a highly successful maiden voyage aboard the STS Orbiter vehicle Challenger on Oct. 5, 1984, as a major payload aboard the STS-41G mission.

Trends in hormone use and ovarian cancer incidence in US white and Australian women: implications for the future.

PubMed

Webb, Penelope M; Green, Adèle C; Jordan, Susan J

2017-05-01

To compare trends in ovarian cancer incidence in the USA and Australia in relation to changes in oral contraceptive pill (OCP) and menopausal hormone therapy (MHT) use. US cancer incidence data (1973-2013) were accessed via SEER*Stat; Australian data (1982-2012) were accessed from the Australian Institute of Health and Welfare Cancer Incidence and Mortality books. Age-period-cohort models were constructed to assess trends in ovarian cancer incidence by birth cohort and year of diagnosis. Ovarian cancer rates were increasing until the cohorts born around 1918 in the USA and 1923 in Australia who were the first to use the OCP. They then declined dramatically across subsequent cohorts such that rates for the 1968 cohort were about half those of women born 45 years earlier; however, there are early suggestions that this decline may not continue in more recent cohorts. In contrast, despite the large reduction in MHT use, there was no convincing evidence that ovarian cancer incidence rates in either country were lower after 2002 than would have been expected based on the declining trend from 1985. The major driver of ovarian cancer incidence rates appears to be the OCP. This means that when those women born since the late 1960s (who have used the OCP at high rates from an early age) reach their 60s and 70s, incidence rates are likely to stop falling and may even increase with changes in the prevalence of other factors such as tubal ligation and obesity. Forward predictions based on past trends may thus underestimate future rates and numbers of women likely to be affected.

Distribution, sources, and air-soil exchange of OCPs, PCBs and PAHs in urban soils of Nepal.

PubMed

Pokhrel, Balram; Gong, Ping; Wang, Xiaoping; Chen, Mengke; Wang, Chuanfei; Gao, Shaopeng

2018-06-01

Due to the high temperature and extensive use of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs), tropical cities could act as secondary sources of these pollutants and therefore received global concern. As compared with other tropical cities, studies on the air-soil exchange of OCPs, PCBs and PAHs in tropical Nepali cities remained limited. In the present study, 39 soil samples from Kathmandu (capital of Nepal) and 21 soil samples from Pokhara (second largest city in Nepal) were collected The soil concentrations of the sum of endosulfans (α- and β-endosulfans) ranged from 0.01 to 16.4 ng/g dw. Meanwhile, ∑dichlorodiphenyltrichloroethane (DDTs) ranged from 0.01 to 6.5 ng/g dw; ∑6PCBs from 0.01 to 9.7 ng/g dw; and ∑15PAHs from 17.1 to 6219 ng/g dw. High concentrations of OCPs were found in the soil of commercial land, while, high soil PAH concentrations were found on tourist/religious and commercial land. Combined the published air concentrations, and the soil data of this study, the directions and fluxes of air-soil exchange were estimated using a fugacity model. It is clear that Nepal is a country contributing prominently to secondary emissions of endosulfans, hexachlorobenzene (HCB), and low molecular weight (LMW) PCBs and PAHs. The flux for all the pollutants in Kathmandu, with ∑endosulfans up to 3553; HCB up to 5263; and ∑LMW-PAHs up to 24378 ng m -2  h -1 , were higher than those in Pokhara. These high flux values indicated the high strength of Nepali soils to act as a source. Copyright © 2018 Elsevier Ltd. All rights reserved.

Quantitative analysis of organizational culture in occupational health research: a theory-based validation in 30 workplaces of the organizational culture profile instrument

PubMed Central

2013-01-01

Background This study advances a measurement approach for the study of organizational culture in population-based occupational health research, and tests how different organizational culture types are associated with psychological distress, depression, emotional exhaustion, and well-being. Methods Data were collected over a sample of 1,164 employees nested in 30 workplaces. Employees completed the 26-item OCP instrument. Psychological distress was measured with the General Health Questionnaire (12-item); depression with the Beck Depression Inventory (21-item); and emotional exhaustion with five items from the Maslach Burnout Inventory general survey. Exploratory factor analysis evaluated the dimensionality of the OCP scale. Multilevel regression models estimated workplace-level variations, and the contribution of organizational culture factors to mental health and well-being after controlling for gender, age, and living with a partner. Results Exploratory factor analysis of OCP items revealed four factors explaining about 75% of the variance, and supported the structure of the Competing Values Framework. Factors were labeled Group, Hierarchical, Rational and Developmental. Cronbach’s alphas were high (0.82-0.89). Multilevel regression analysis suggested that the four culture types varied significantly between workplaces, and correlated with mental health and well-being outcomes. The Group culture type best distinguished between workplaces and had the strongest associations with the outcomes. Conclusions This study provides strong support for the use of the OCP scale for measuring organizational culture in population-based occupational health research in a way that is consistent with the Competing Values Framework. The Group organizational culture needs to be considered as a relevant factor in occupational health studies. PMID:23642223

Distribution and speciation of mercury affected by humic acid in mariculture sites at the Pearl River estuary.

PubMed

Ding, Lingyun; Zhao, Kaiyun; Zhang, Lijuan; Liang, Peng; Wu, Shengchun; Wong, Ming Hung; Tao, Huchun

2018-05-14

At the Pearl River Estuary of southern China, mercury and its environmental problems have long been a great concern. This study investigated the distribution and speciation of mercury compounds that are significantly influenced by the increasing content of humic acid (HA, a model natural organic matter) in this region. The inorganic mercury and methyl mercury, being adsorbed and converted at different HA levels, were studied in sediments and surface water at both mariculture and their reference sites. In mariculture sediments with higher HA content (up to 4.5%), more mercury were adsorbed at different compound levels, promoting the methylation and accumulation of mercury (P < 0.05) at the sediment-water interface. Seasonal shift in environmental temperature might control the HA content, subsequently favouring mercury methylation (maximum 1.75 ± 0.08 mg L -1 d -1 ) under warm weather conditions. In reference sites received less HA wastes, lower adsorption capacity and methylation rate were observed for mercury in sediments and surface water. Our work points to the significant roles of HA on mercury distribution and speciation both spatially and seasonally, thus addressing the impacts of mariculture activities on estuary eco-system. Copyright © 2018 Elsevier Ltd. All rights reserved.

Endothelial function and insulin resistance in polycystic ovary syndrome: the effects of medical therapy.

PubMed

Teede, Helena J; Meyer, Caroline; Hutchison, Samantha K; Zoungas, Sophia; McGrath, Barry P; Moran, Lisa J

2010-01-01

To assess the interaction between insulin resistance and endothelial function and the optimal treatment strategy addressing cardiovascular risk in polycystic ovary syndrome. Randomized controlled trial. Controlled clinical study. Overweight age- and body mass index-matched women with polycystic ovary syndrome. Six months metformin (1 g two times per day, n = 36) or oral contraceptive pill (OCP) (35 microg ethinyl E(2)-2 mg cytoproterone acetate, n = 30). Fasting and oral glucose tolerance test glucose and insulin levels, endothelial function (flow-mediated dilation, asymmetric dimethylarginine, plasminogen activator inhibitor-1, von Willebrand factor), inflammatory markers (high-sensitivity C-reactive protein), lipids, and hyperandrogenism. The OCP increased levels of glucose and insulin on oral glucose tolerance test, high-sensitivity C-reactive protein, triglycerides, and sex-hormone binding globulin and decreased levels of low-density lipoprotein cholesterol and T. Metformin decreased levels of fasting insulin, oral glucose tolerance test insulin, high-density lipoprotein cholesterol, and high-sensitivity C-reactive protein. Flow-mediated dilation increased only with metformin (+2.2% +/- 4.8%), whereas asymmetric dimethylarginine decreased equivalently for OCP and metformin (-0.3 +/- 0.1 vs. -0.1 +/- 0.1 mmol/L). Greater decreases in plasminogen activator inhibitor-1 occurred for the OCP than for metformin (-1.8 +/- 1.6 vs. -0.7 +/- 1.7 U/mL). In polycystic ovary syndrome, metformin improves insulin resistance, inflammatory markers, and endothelial function. The OCP worsens insulin resistance and glucose homeostasis, inflammatory markers, and triglycerides and has neutral or positive endothelial effects. The effect of the OCP on cardiovascular risk in polycystic ovary syndrome is unclear. Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

The status of organochlorine pesticide contamination in the soils of the Campanian Plain, southern Italy, and correlations with soil properties and cancer risk.

PubMed

Qu, Chengkai; Albanese, Stefano; Chen, Wei; Lima, Annamaria; Doherty, Angela L; Piccolo, Alessandro; Arienzo, Michele; Qi, Shihua; De Vivo, Benedetto

2016-09-01

The distribution, inventory, and potential risk of organochlorine pesticides (OCPs), including Hexachlorocyclohexanes (HCHs) and Dichlorodiphenyltrichloroethanes (DDTs), and their correlation with soil properties and anthropogenic factors were investigated in soils of the Campanian Plain. The total concentrations of HCHs and DDTs ranged from 0.03 to 17.3 ng/g (geometric mean: GM = 0.05 ng/g), and 0.08-1231 ng/g (GM = 14.4 ng/g), respectively. In general, the concentration of OCPs in farmland and orchards was higher than on land used for non-agricultural purposes. There are significant differences in the concentration of OCPs in the soils across the region, more specifically, the Acerra-Marigliano conurbation (AMC) and Sarno River Basin (SRB) are recognized as severely OCP-contaminated areas. The recent application of technical HCHs and DDTs in large quantities appears unlikely in light of the ratio of α-HCH/β-HCH and p,p'-DDT/p,p'-DDE, and the prohibition of the use of these chemicals in Italy nearly forty years ago. The clear correlation between the concentration of DDTs and organic carbon suggests a typical secondary distribution pattern. The mass inventory of OCPs in soils of the Campanian Plain is estimated to have a GM of 17.3 metric tons. There is no clear evidence linking the impact of geographical distribution of OCPs on the incidence of cancer, and the 95% confidence interval of total incremental lifetime cancer risk (TILCR) data falls below the internationally accepted benchmark value of 1 × 10(-5). Copyright © 2016 Elsevier Ltd. All rights reserved.

Residues of organochlorine pesticides in surface water of a megacity in central China: seasonal-spatial distribution and fate in Wuhan.

PubMed

Cui, Lili; Wei, Liangfu; Wang, Jun

2017-01-01

Surface water quality closely correlating with human health suffered increasing organochlorine pesticide (OCP) pollution due to the intensive anthropogenic activities in megacities. In the present study, 112 water samples collected from 14 lakes and 11 drinking water source sites in Wuhan were detected for the residues of OCPs in November 2013 and July 2014, respectively. The ΣOCPs ranged from 5.61 to 13.62 ng L -1 in summer with the maximum value in Yezhi Lake and 3.18 to 7.73 ng L -1 in winter with the highest concentration in Yandong Lake. Except dichlorodiphenyltrichloroethanes (DDTs), OCP concentrations in summer were significantly higher than those in winter mostly due to the non-point source pollution including land runoff in summer. Source apportionment of hexachlorocyclohexanes (HCHs) and DDTs revealed the historical use of technical HCH and lindane and the new input of DDT, respectively. The spatial distribution of OCPs was not uniform in the surface water of Wuhan because of the significant influence of land development and fishery. The risk assessments showed the heptachlor, and heptachlor epoxide in most sampling sites exceeded the threshold set by the European Union, indicating the possible adverse effects for aquatic lives. Negligible non-carcinogenic risks for drinking and bathing as well as carcinogenic risks for bathing were found in the surface water. However, the total carcinogenic risks of all OCPs (∑Rs) caused by drinking in summer were higher than the safe level of 10 -7 in all sampling sites. It was implied that the surface water in Wuhan was not safe for directly drinking without effective purification.

Determination of plasma concentrations of organochlorine pesticides and polychlorinated biphenyls in pet cats and dogs.

PubMed

Yavuz, Oguzhan; Arslan, Handan Hilal; Esin, Cagatay; Das, Yavuz Kursad; Aksoy, Abdurrahman

2018-01-01

The aim of this study was the determination of plasma concentrations of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in cats and dogs and evaluation of their prevalence and possible effects. The concentrations of nine OCPs, such as α-hexachlorocyclohexane (HCH), β-HCH, γ-HCH, hexachlorobenzene (HCB), aldrin, 2,4'-dichlorodiphenyltrichloroethane (2,4'-DDT), 4,4'-DDT, 2,4'-dichlorodiphenyldichloroethylene (2,4'-DDE) and 4,4'-DDE and 16 PCBs (PCB-28, -52, -70, -74, -81, -99, -101, -118, -138, -153, -156, -170, -180, -183, -187 and -208) were evaluated in the plasma samples of pet cats ( n = 15) and dogs ( n = 21). The concentrations of OCPs ranged from 1.12 ng g -1 lipid weight (lw) to 7.65 ng g -1 lw in cats and from 1.25 ng g -1 lw to 6.79 ng g -1 lw in dogs. In addition, mean PCB levels were 0.58-5.66 and 0.52-6.62 ng g -1 lw in cats and dogs, respectively. β-HCH, γ-HCH and PCB-138 levels were significantly higher in dogs ( p < 0.05). As far as could be determined, OCPs and PCBs were detected in the plasma samples of domestic cats and dogs in Turkey for the first time. Their concentrations were similar to those reported in earlier studies abroad. However, in contrast to other research, the levels of some OCPs were higher in dogs than in cats. It is concluded that, because of their high prevalence and potential health effects in animals and humans, OCP and PCB levels should be monitored systematically in domestic cats and dogs.

Seasonal variation of organochlorine pesticides in the gaseous phase and aerosols over the East China Sea

NASA Astrophysics Data System (ADS)

Ji, Tianyi; Lin, Tian; Wang, Fengwen; Li, Yuanyuan; Guo, Zhigang

2015-05-01

Eighty paired gaseous phase and PM2.5 (particulate matter < 2.5 μm in diameter) samples, covering four seasons from October 2011 to August 2012 were collected simultaneously from a remote island in the East China Sea (ECS). The samples were analyzed for organochlorine pesticides (OCPs) to determine their seasonal variation and potential sources over the coastal marine environment. The concentrations of individual OCPs in the PM2.5 samples were higher in winter and lower in summer, and the reverse trend was observed for the measured OCP compounds (except hexachlorocyclohexanes, HCHs) in the gaseous phase. Principal component analysis revealed one trend that contributed 40% to PM2.5-bound OCPs characterized by β-HCH, α-HCH, p,p‧-dichlorodiphenyldichloroethane (p,p‧-DDD), p,p‧-dichlorodiphenyldichloroethylene (p,p‧-DDE), and chlordanes; whereas two seasonal trends, represented by dichlorodiphenyltrichloroethanes (DDTs) or chlordanes and HCHs, were responsible for 38% and 23% of the gaseous OCPs, respectively. Continental outflow driven by the East Asian monsoon brought large quantities of particulate OCPs to the ECS, especially in winter. Possible fresh sources or net volatilization from the Yangtze River induced by both higher ambient temperature and higher discharge rates caused the higher gaseous DDT and chlordane levels observed in summer. However, the lower concentrations of gaseous HCHs observed in summer suggested that net volatilization had a relatively limited impact on gaseous HCHs due to the long-term prohibition of their use and their low residual levels in the catchment, whereas the elevated concentrations of gaseous HCHs in winter controlled by gas-particle partitioning, resulted from increased particulate HCHs producing a partial shift to gaseous HCHs over ECS.

Expression of prostaglandin E receptor subtype EP4 in conjunctival epithelium of patients with ocular surface disorders: case-control study.

PubMed

Ueta, Mayumi; Sotozono, Chie; Yamada, Keiko; Yokoi, Norihiko; Inatomi, Tsutomu; Kinoshita, Shigeru

2012-01-01

To confirm the downregulation of PTGER4 mRNA in the conjunctiva of Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) and ocular cicatricial pemphigoid (OCP) patients and to examine the expression of its EP4 protein in the conjunctival epithelium of patients with various ocular surface disorders. Case-control study. We performed quantitative reverse transcription-PCR (RT-PCR) analysis of PTGER4 mRNA in conjunctival tissue sections from patients with SJS/TEN and OCP to confirm the downregulation of PTGER4 mRNA expression. We also analysed EP4 immunohistologically in other ocular surface disorders. Conjunctival tissues were obtained from patients undergoing surgical reconstruction of the ocular surface due to chemical eye burns, subacute SJS/TEN or chronic SJS/TEN, chronic OCP, severe graft versus host disease (GVHD) and from patients with Mooren's ulcers treated by resection of the inflammatory conjunctiva. The expression of PTGER4 mRNA and EP4 protein assessed by quantitative RT-PCR assay and immunohistological methods. PTGER4 mRNA was significantly lower in conjunctival tissues from SJS and OCP patients than in the control conjunctivochalasis samples. EP4 protein was detected in conjunctival epithelium from patients with chemical eye burn and in control conjunctival epithelium from patients with conjunctivochalasis. Its expression varied in conjunctival epithelium from patients with Mooren's ulcer. We did not detect EP4 immunoreactivity in conjunctival epithelium from patients with subacute SJS/TEN, severe GVHD, chronic SJS/TEN or OCP. The strong downregulation of EP4 expression in conjunctival epithelium from patients with OCP or SJS/TEN may be attributable to ocular surface inflammation.

Expression of prostaglandin E receptor subtype EP4 in conjunctival epithelium of patients with ocular surface disorders: case-control study

PubMed Central

Ueta, Mayumi; Sotozono, Chie; Yamada, Keiko; Yokoi, Norihiko; Inatomi, Tsutomu; Kinoshita, Shigeru

2012-01-01

Objectives To confirm the downregulation of PTGER4 mRNA in the conjunctiva of Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) and ocular cicatricial pemphigoid (OCP) patients and to examine the expression of its EP4 protein in the conjunctival epithelium of patients with various ocular surface disorders. Design Case-control study. Setting and participants We performed quantitative reverse transcription-PCR (RT-PCR) analysis of PTGER4 mRNA in conjunctival tissue sections from patients with SJS/TEN and OCP to confirm the downregulation of PTGER4 mRNA expression. We also analysed EP4 immunohistologically in other ocular surface disorders. Conjunctival tissues were obtained from patients undergoing surgical reconstruction of the ocular surface due to chemical eye burns, subacute SJS/TEN or chronic SJS/TEN, chronic OCP, severe graft versus host disease (GVHD) and from patients with Mooren's ulcers treated by resection of the inflammatory conjunctiva. Primary and secondary outcome measures The expression of PTGER4 mRNA and EP4 protein assessed by quantitative RT-PCR assay and immunohistological methods. Results PTGER4 mRNA was significantly lower in conjunctival tissues from SJS and OCP patients than in the control conjunctivochalasis samples. EP4 protein was detected in conjunctival epithelium from patients with chemical eye burn and in control conjunctival epithelium from patients with conjunctivochalasis. Its expression varied in conjunctival epithelium from patients with Mooren's ulcer. We did not detect EP4 immunoreactivity in conjunctival epithelium from patients with subacute SJS/TEN, severe GVHD, chronic SJS/TEN or OCP. Conclusions The strong downregulation of EP4 expression in conjunctival epithelium from patients with OCP or SJS/TEN may be attributable to ocular surface inflammation. PMID:23065448

Effects of MgO and SiO2 on Plasma-Sprayed Hydroxyapatite Coating: An in Vivo Study in Rat Distal Femoral Defects.

PubMed

Ke, Dongxu; Robertson, Samuel F; Dernell, William S; Bandyopadhyay, Amit; Bose, Susmita

2017-08-09

Plasma-sprayed hydroxyapatite (HA)-coated titanium implants have been widely used in orthopedic applications due to their inheritance of an excellent mechanical property from titanium and great osteoconductivity from HA. However, the lack of osteoinductivity limits their further applications. In this study, 1 wt % MgO and 0.5 wt % SiO 2 were mixed with HA for making plasma-sprayed coatings on titanium implants. Plasma-sprayed HA- and MgO/SiO 2 -HA-coated titanium implants showed adhesive bond strengths of 25.73 ± 1.92 and 23.44 ± 2.89 MPa, respectively. The presence of MgO and SiO 2 significantly increased the osteogenesis, osseointegration, and bone mineralization of HA-coated titanium implants by the evaluation of their histomorphology after 6, 10, and 14 weeks of implantation in rat distal femoral defects. Implant pushout tests also showed a shear modulus of 149.83 ± 3.69 MPa for MgO/SiO 2 -HA-coated implants after 14 weeks of implantation, compared to 52.68 ± 10.41 MPa for uncoated implants and 83.92 ± 3.68 MPa for pure HA-coated implants; These are differences in the shear modulus of 96% and 56.4%, respectively. This study assesses for the first time the quality of the bone-implant interface of induction plasma-sprayed MgO and SiO 2 binary-doped HA coatings on load-bearing implants compared to bare titanium and pure HA coatings in a quantitative manner. Relating the osseointegration and interface shear modulus to the quality of implant fixation is critical to the advancement and implementation of HA-coated orthopedic implants.

Effect of the Interposition of Calcium Phosphate Materials on Tendon-Bone Healing During Repair of Chronic Rotator Cuff Tear.

PubMed

Zhao, Song; Peng, Lingjie; Xie, Guoming; Li, Dingfeng; Zhao, Jinzhong; Ning, Congqin

2014-08-01

The current nature of tendon-bone healing after rotator cuff (RC) repair is still the formation of granulation tissue at the tendon-bone interface rather than the formation of fibrocartilage, which is the crucial structure in native tendon insertion and can be observed after knee ligament reconstruction. The interposition of calcium phosphate materials has been found to be able to enhance tendon-bone healing in knee ligament reconstruction. However, whether the interposition of these kinds of materials can enhance tendon-bone healing or even change the current nature of tendon-bone healing after RC repair still needs to be explored. The interposition of calcium phosphate materials during RC repair would enhance tendon-bone healing or change its current nature of granulation tissue formation into a more favorable process. Controlled laboratory study. A total of 144 male Sprague-Dawley rats underwent unilateral detachment of the supraspinatus tendon, followed by delayed repair after 3 weeks. The animals were allocated into 1 of 3 groups: (1) repair alone, (2) repair with Ca5(PO4)2SiO4 (CPS) bioceramic interposition, or (3) repair with hydroxyapatite (HA) bioceramic interposition at the tendon-bone interface. Animals were sacrificed at 2, 4, or 8 weeks postoperatively, and microcomputed tomography (micro-CT) was used to quantify the new bone formation at the repair site. New fibrocartilage formation and collagen organization at the tendon-bone interface was evaluated by histomorphometric analysis. Biomechanical testing of the supraspinatus tendon-bone complex was performed. Statistical analysis was performed using 1-way analysis of variance. Significance was set at P < .05. The micro-CT analysis demonstrated remarkable osteogenic activity and osteoconductivity to promote new bone formation and ingrowth of CPS and HA bioceramic, with CPS bioceramic showing better results than HA. Histological observations indicated that CPS bioceramic had excellent biocompatibility and biodegradability. At early time points after the RC repair, CPS bioceramic significantly increased the area of fibrocartilage at the tendon-bone interface compared with the control and HA groups. Moreover, CPS and HA bioceramics had significantly improved collagen organization. Biomechanical tests indicated that the CPS and HA groups have greater ultimate load to failure and stiffness than the control group at 4 and 8 weeks, and the CPS specimens exhibited the maximum ultimate load to failure, stiffness, and stress of the healing enthesis. Both CPS and HA bioceramics aid in cell attachment and proliferation and accelerate new bone formation, and CPS bioceramic has a more prominent effect on tendon-to-bone healing. Local application of CPS and HA bioceramic at the tendon-bone interface shows promise in improving healing after rotator cuff tear repair. © 2014 The Author(s).

Remediation of organochlorine pesticides (OCPs) contaminated site by successive methyl-β-cyclodextrin (MCD) and sunflower oil enhanced soil washing - Portulaca oleracea L. cultivation.

PubMed

Ye, Mao; Sun, Mingming; Hu, Feng; Kengara, Fredrick Orori; Jiang, Xin; Luo, Yongming; Yang, Xinlun

2014-06-01

An innovative ex situ soil washing technology was developed in this study to remediate organochlorine pesticides (OCPs)-contaminated site. Elevated temperature (50 °C) combined with ultrasonication (35 kHz, 30 min) at 25 g L(-1) methyl-β-cyclodextrin and 100 mL L(-1) sunflower oil were effective in extracting OCPs from the soil. After four successive washing cycles, the removal efficiency for total OCPs, DDTs, endosulfans, 1,2,3,4,5,6-hexachlorocyclohexanes, heptachlors, and chlordanes were all about 99%. The 4th washed soil with 3 months cultivation of Portulaca oleracea L. and nutrient addition significantly increase (p<0.05) the number, biomass carbon, nitrogen, and functioning diversity of soil microorganisms. This implied that the microbiological functioning of the soil was at least partially restored. This combined cleanup strategy proved to be effective and environmental friendly. Copyright © 2014 Elsevier Ltd. All rights reserved.

Human health risk assessment of pesticide residues in snappers (Lutjanus) fish from the Navachiste Lagoon complex, Mexico.

PubMed

Granados-Galván, Ingrid Alejandra; Rodríguez-Meza, Durga Guadalupe; Luna-González, Antonio; González-Ocampo, Héctor Abelardo

2015-08-15

Organochlorine pesticides (OCPs) residues were determined in fillets of Lutjanus colorado, L. argentiventris, and L. novemfasciatus. Fillet samples were collected bimonthly from February 2012 to February 2013. OCPs average concentrations do not differ significantly according to size, weight, or season, nor do they relate with the physico-chemical parameters of the sea water. The highest concentration and most frequently encountered OCPs were endosulfan sulfate, δ-HCH, and heptachlor epoxide, which indicates their use in the recent past and confirms their persistence. Average concentrations of ∑HCHs, ∑chlordane, and ∑heptachlor in samples were above cancer MRLs according to data from monthly consumed portions. HCHs and heptachlor are listed in Appendix III of the Rotterdam Convention of chemicals placed on a prior informed consent procedure for import and export purposes; they are considered illegal in Mexico. The OCPs concentrations above cancer MRLs in Lutjanus spp. turn its frequent consumption into a human health risk. Copyright © 2015 Elsevier Ltd. All rights reserved.

Local and global structural drivers for the photoactivation of the orange carotenoid protein

DOE PAGES

Gupta, Sayan; Guttman, Miklos; Leverenz, Ryan L.; ...

2015-09-18

Here, photoprotective mechanisms are of fundamental importance for the survival of photosynthetic organisms. In cyanobacteria, the orange carotenoid protein (OCP), when activated by intense blue light, binds to the light-harvesting antenna and triggers the dissipation of excess captured light energy. Using a combination of small angle X-ray scattering (SAXS), X-ray hydroxyl radical footprinting, circular dichroism, and H/D exchange mass spectrometry, we identified both the local and global structural changes in the OCP upon photoactivation. SAXS and H/D exchange data showed that global tertiary structural changes, including complete domain dissociation, occur upon photoactivation, but with alteration of secondary structure confined tomore » only the N terminus of the OCP. Microsecond radiolytic labeling identified rearrangement of the H-bonding network associated with conserved residues and structural water molecules. Collectively, these data provide experimental evidence for an ensemble of local and global structural changes, upon activation of the OCP, that are essential for photoprotection.« less

Biomagnification and enantiomeric profiles of organochlorine pesticides in food web components from Zhoushan Fishing Ground, China.

PubMed

Zhou, Shanshan; Pan, Yongqiang; Zhang, Lina; Xue, Bin; Zhang, Anping; Jin, Meiqing

2018-06-01

Trophodynamics and chiral signatures of organochlorine pesticides (OCPs), including dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexanes (HCHs), and chlordanes in a food web from Zhoushan Fishing Ground, China, were studied. Residues of OCPs in all teleost fishes were within food safety levels. Strong positive correlations were found between trophic levels (TLs) and wet weight concentrations of target chemicals, with trophic magnification factors (TMFs) from 4.17 to 9.77. Lipid contents and TLs significantly correlated, which indirectly affect the bioaccumulation processes of OCPs. The consistently racemic EF values of α-HCH, as well as invariability of the relative proportions of HCH isomers in different marine species implied that HCHs in animals originate directly from the surrounding environment. However, in vivo biotransformation and/or elimination of o,p'-DDT cannot be precluded. TMFs of the individual enantiomers further suggest that the influence of achiral biotransformation is too minor to induce enantioselective biomagnification of chiral OCPs through the studied food web. Copyright © 2018 Elsevier Ltd. All rights reserved.

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in harbor sediments from Sea Lots, Port-of-Spain, Trinidad and Tobago

USGS Publications Warehouse

Mohammed, Azad; Peterman, Paul; Echols, Kathy; Feltz, Kevin; Tegerdine, George; Manoo, Anton; Maraj, Dexter; Agard, John; Orazio, Carl

2011-01-01

Concentrations of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were determined in nearshore marine surficial sediments from three locations in Trinidad. Sediments were sampled at Sea Lots on the west coast, in south Port-of-Spain Harbor, south of Sea Lots at Caroni Lagoon National Park, and on Trinidad's east coast at Manzanilla. Total PCB concentrations in Sea Lots sediments ranged from 62 to 601 ng/g (dry weight {dw}), which was higher than at Caroni and Manzanilla, 13 and 8 ng/g dw, respectively. Total OCP concentrations at Sea Lots were ranged from 44.5 to 145 ng/g dw, compared with 13.1 and 23.8 n/g (dw), for Caroni and Manzanilla respectively. The concentrations of PCBs and of some OCPs in sediments from Sea Lots were above the Canadian interim sediment quality guidelines. To date, this data is the first report on the levels of PCBs and other organochlorine compounds from Trinidad and Tobago.

A liquid-phase microextraction method, combining a dual gauge microsyringe with a hollow fiber membrane, for the determination of organochlorine pesticides in aqueous solution by gas chromatography/ion trap mass spectrometry.

PubMed

Yan, Chih-Hao; Wu, Hui-Fen

2004-01-01

A liquid-phase microextraction (LPME) method has been demonstrated for the extraction and determination of organochlorine pesticides (OCPs) in aqueous solution. The method combines a dual gauge microsyringe with a hollow fiber membrane (LPME/DGM-HF) followed by detection by gas chromatography/ion trap mass spectrometry (GC/ITMS). The advantages include speed, low solvent and sample consumption, simplicity and ease of use. The extraction time, solvent selection, salt concentration and sample stirring rate have been investigated in order to optimize extraction efficiency. The viability is evaluated by measuring the linearity and detection limit of the five OCPs in aqueous solution. Detection linearity for the OCPs has been achieved over a range of concentrations between 1 and 500 microg/L (r2 > 0.930), with a detection limit of 0.1 microg/L for each OCP. Copyright 2004 John Wiley & Sons, Ltd.

Local and global structural drivers for the photoactivation of the orange carotenoid protein

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gupta, Sayan; Guttman, Miklos; Leverenz, Ryan L.

Here, photoprotective mechanisms are of fundamental importance for the survival of photosynthetic organisms. In cyanobacteria, the orange carotenoid protein (OCP), when activated by intense blue light, binds to the light-harvesting antenna and triggers the dissipation of excess captured light energy. Using a combination of small angle X-ray scattering (SAXS), X-ray hydroxyl radical footprinting, circular dichroism, and H/D exchange mass spectrometry, we identified both the local and global structural changes in the OCP upon photoactivation. SAXS and H/D exchange data showed that global tertiary structural changes, including complete domain dissociation, occur upon photoactivation, but with alteration of secondary structure confined tomore » only the N terminus of the OCP. Microsecond radiolytic labeling identified rearrangement of the H-bonding network associated with conserved residues and structural water molecules. Collectively, these data provide experimental evidence for an ensemble of local and global structural changes, upon activation of the OCP, that are essential for photoprotection.« less

Residues of organochlorine pesticides in intertidal flat surface sediments from coastal zone of Jiangsu Province, China

NASA Astrophysics Data System (ADS)

Han, Xiumei; Zheng, Rong; Zhao, Jiale; Ma, Chao; Gao, Xiaojiang

2014-09-01

Sixteen surface sediment samples were collected and analysed to evaluate the residues of organochlorine pesticides (OCPs) from intertidal flat in Jiangsu Province. Overall, 22 OCPs were detected with total concentrations of OCPs ranging widely from 0.96 to 12.14 ng/g (dry wt). Total hexachlorocyclohexane (HCH) and total dichlorodiphenyltrichloroethane (DDT) levels varied from <0.01 to 0.67 ng/g and from 0.23 to 4.85 ng/g, respectively. DDTs were the predominant compounds. The dominance of β-HCH indicated a history of HCH pollution. According to the ratios of ( p, p'-DDD+ p, p'-DDE)/ p, p'-DDT and o,p'-DDT/ p, p'-DDT, new input of DDTs did not occur in most sites, and the main sources were historical usage of technical DDTs. OCPs such as dieldrin, endrin, p, p'-DDD, and p, p'-DDT exceeded the effects range low, showing adverse biological effects that would occasionally occur at some sites of the study area.

Investigating the Spatial Trends in the Level of Organic Contaminants in the Ethiopian Rift Valley Lakes Using Semipermeable Membrane Devices.

PubMed

Deribe, Ermias

2018-05-21

Organic pollutants in the Ethiopian Rift Valley Lakes are the major factors that contribute to severe environmental problem. SPMDs were deployed for the analysis of selected organic pollutants for 1 month at 2 sites in Lakes Hawassa, Ziway and Koka, Ethiopia. From SPMDs placed in the three lakes, the predominant OCPs were DDT which comprise 67% and followed by endosulfan 23% of the total organochlorine pesticides (OCPs) retrieved. The highest level of OCPs, in general, was found in the SPMDs deployed in Lake Ziway with the mean concentration of 308.5 ng/SPMD. However, the concentrations of polychlorinated biphenyls (PCBs) were the highest in the SPMDs deployed in Lake Hawassa with mean concentration of 50.2 ng/SPMD. Spatial variation on the accumulation of OCPs and PCBs among the lakes depends on the shoreline activities, distance of the lakes from point and non-point sources, and the biofouling factors.

PXR-dependent induction of human CYP3A4 gene expression by organochlorine pesticides.

PubMed

Coumoul, Xavier; Diry, Monique; Barouki, Robert

2002-11-15

OCP are xenobiotics which display various toxic effects on animal and human health. One of their effects is to bind and activate estrogen receptor alpha (ERalpha). We have previously studied the down-regulation of induced CYP1A1 (cytochrome P450) expression by this class of molecules in mammary carcinoma cells and shown the importance of ERalpha in this process. However, an alternative mechanism was suggested by those experiments in hepatoma cells. In this study, we have performed Northern blot and transient transfection assays in various cell lines and shown that OCP activate human pregnane X receptor (PXR) and subsequent CYP3A4 mRNA expression. This effect is mediated by the distal xenobiotic responsive element modulator of the promoter. The induction of CYP3A4 by OCP was dose-dependent within the 1-10 microM range. The data suggest that chronic exposure to OCP could alter a major metabolite pathway in human liver and putatively modify the pharmacokinetics of drugs and pollutants.

Air-Water Exchange of Legacy and Emerging Organic Pollutants across the Great Lakes

NASA Astrophysics Data System (ADS)

Lohmann, R.; Ruge, Z.; Khairy, M.; Muir, D.; Helm, P.

2014-12-01

Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) are transported to great water bodies via long-range atmospheric transport and released from the surface water as air concentrations continue to diminish. As the largest fresh water bodies in North America, the Great Lakes have both the potential to accumulate and serve as a secondary source of persistent bioaccumulative toxins. OCP and PCB concentrations were sampled at 30+ sites across Lake Superior, Ontario and Erie in the summer of 2011. Polyethylene passive samplers (PEs) were simultaneously deployed in surface water and near surface atmosphere to determine air-water gaseous exchange of OCPs and PCBs. In Lake Superior, surface water and atmospheric concentrations were dominated by α-HCH (average 250 pg/L and 4.2 pg/m3, respectively), followed by HCB (average 17 pg/L and 89 pg/m3, respectively). Air-water exchange varied greatly between sites and individual OCPs, however α-endosulfan was consistently deposited into the surface water (average 19 pg/m2/day). PCBs in the air and water were characterized by penta- and hexachlorobiphenyls with distribution along the coast correlated with proximity to developed areas. Air-water exchange gradients generally yielded net volatilization of PCBs out of Lake Superior. Gaseous concentrations of hexachlorobenzene, dieldrin and chlordanes were significantly higher (p < 0.05) at Lake Erie than Lake Ontario. A multiple linear regression that incorporated meteorological, landuse and population data was used to explain variability in the atmospheric concentrations. Results indicated that landuse (urban and/or cropland) greatly explained the variability in the data. Freely dissolved concentrations of OCPs (

Spatial correlation analysis of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) in sediments between Taihu Lake and its tributary rivers.

PubMed

Zhao, Zhonghua; Jiang, Yu; Li, Qianyu; Cai, Yongjiu; Yin, Hongbin; Zhang, Lu; Zhang, Jin

2017-08-01

The residues of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) in surface sediments from Taihu Lake basin (THB) and Taihu Lake body (THL) were investigated. Higher concentrations of both PAHs and OCPs were observed for THB than THL. The concentrations of PAHs ranged from 12.1 to 2281.1ngg -1 dw for THB and from 11.4 to 209.9ngg -1 dw for THL, while OCPs ranged from 16.3 to 96.9ngg -1 dw and from 16.8 to 61.9ngg -1 dw for THB and THL, respectively. Spatial distribution of PAHs and OCPs showed a high correspondence with the land use of THB and surrounding anthropogenic activity. Additionally, the Kriging interpolation plots demonstrated that the major upper reaches were more polluted than the lower reaches, indicating the transport of pollutants with the water flow direction. The organic matter contents were responsible for OCP distribution other than PAHs due to the biodegradation capacity difference of chemicals. Similar compositions of pollutants were observed with 3- and 4-ringed PAHs accounting for a total of 78.3% for THB and 85.8% for THL, respectively. HCHs and DDTs were predominant OCPs, which contributed to 31.8% and 21.7% for THB, and 33.6% and 21.9% for THL, respectively. The isomeric and parent substance/metabolite ratios implied fresh inputs of DDTs and chlordanes, while HCHs and endosulfans were mainly from old usage. PAH source identification performed by diagnostic ratios demonstrated the mixed sources of petrogenic and pyrogenic ones dominated by grass, wood and coal combustion. Furthermore, the hazard quotient (HQ) based on the consensus-based sediment quality guidelines (SQGs) was used to evaluate the ecological risks of sediments. Although no frequently adverse effects were observed, potential ecological risks induced by Ant, BaA, γ-HCH, dieldrin, p,p'-DDT and chlordanes should also be paid attention to considering the continuous inputs of such pollutants. Copyright © 2017 Elsevier Inc. All rights reserved.

Incidence of oral cavity and pharynx cancer in New Hampshire, 1990-2007.

PubMed

Cherala, Sai S; Kelley, Kristina

2012-01-01

The purpose of this study is to describe trends of the statewide cancer and treatment-related characteristics of oral cavity and pharynx (OCP) cancer and prevalence of risk factors in New Hampshire residents from 1990-2007. This is a descriptive study on oral cavity and pharynx cancer using a state cancer registry dataset for 1990- 2007. The age-adjusted rates with 95% confidence intervals for cancer incidence rates and standard proportions for stage, treatment, and risk factors were calculated. The Joinpoint regression model was used for assessing linear trends for cancer rates. The overall differences for the period under study between age, female and male rate, and stage were analyzed using the test. During 1990-2007, oral cavity and pharynx cancer incidence rates for New Hampshire residents have remained stable. The cancer incidence rates have decreased for older age groups (greater than 59) and the 50-59 age group has shown increase in incidence rate of OCP cancer since 1990. There is significant increase in the late-stage diagnoses from 1990-2007. Early detection through periodic medical and dental examinations can reduce the risk of these cancers. Public health strategies that address the gaps identified by this study can reduce OCP cancer and protect the health of the New Hampshire population.

Evaluation of runoff prediction from WEPP-based erosion models for harvested and burned forest watersheds

Treesearch

S. A. Covert; P. R. Robichaud; W. J. Elliot; T. E. Link

2005-01-01

This study evaluates runoff predictions generated by GeoWEPP (Geo-spatial interface to the Water Erosion Prediction Project) and a modified version of WEPP v98.4 for forest soils. Three small (2 to 9 ha) watersheds in the mountains of the interior Northwest were monitored for several years following timber harvest and prescribed fires. Observed climate variables,...

Fortifying the Bone-Implant Interface Part 2: An In Vivo Evaluation of 3D-Printed and TPS-Coated Triangular Implants.

PubMed

MacBarb, Regina F; Lindsey, Derek P; Woods, Shane A; Lalor, Peggy A; Gundanna, Mukund I; Yerby, Scott A

2017-01-01

Minimally invasive surgical fusion of the sacroiliac (SI) joint using machined solid triangular titanium plasma spray (TPS) coated implants has demonstrated positive clinical outcomes in SI joint pain patients. Additive manufactured (AM), i.e. 3D-printed, fenestrated triangular titanium implants with porous surfaces and bioactive agents, such as nanocrystalline hydroxyapatite (HA) or autograft, may further optimize bony fixation and subsequent biomechanical stability. A bilateral ovine distal femoral defect model was used to evaluate the cancellous bone-implant interfaces of TPS-coated and AM implants. Four implant groups (n=6/group/time-point) were included: 1)TPS-coated, 2)AM, 3)AM+HA, and 4)AM+Autograft. The bone-implant interfaces of 6- and 12-week specimens were investigated via radiographic, biomechanical, and histomorphometric methods. Imaging showed peri-implant bone formation around all implants. Push-out testing demonstrated forces greater than 2500 N, with no significant differences among groups. While TPS implants failed primarily at the bone-implant interface, AM groups failed within bone ~2-3mm away from implant surfaces. All implants exhibited bone ongrowth, with no significant differences among groups. AM implants had significantly more bone ingrowth into their porous surfaces than TPS-coated implants ( p <0.0001). Of the three AM groups, AM+Auto implants had the greatest bone ingrowth into the porous surface and through their core ( p <0.002). Both TPS and AM implants exhibited substantial bone ongrowth and ingrowth, with additional bone through growth into the AM implants' core. Overall, AM implants experienced significantly more bone infiltration compared to TPS implants. While HA-coating did not further enhance results, the addition of autograft fostered greater osteointegration for AM implants. Additive manufactured implants with a porous surface provide a highly interconnected porous surface that has comparatively greater surface area for bony integration. Results suggest this may prove advantageous toward promoting enhanced biomechanical stability compared to TPS-coated implants for SI joint fusion procedures.

An operational computer program to control Self Defense Surface Missile System operations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roe, C.L.

1991-12-01

An account is given of the system architecture and operational protocols of the NATO Seasparrow Surface Missile System (NSSMS) Operational Computer Program (OCP) which has been developed, and is being deployed multinationally, to respond against antiship missiles. Flowcharts are presented for the target detection and tracking, control, and engagement phases of the Self Defense Surface Missile System that is controlled by the OCP. USN and other NATO vessels will carry the NSSMS well into the next century; the OCP presently described will be deployed in the course of 1992 to enhance the self-defense capabilities of the NSSMS-equipped fleet. 8 refs.

A Modular Approach To Study Protein Adsorption on Surface Modified Hydroxyapatite.

PubMed

Ozhukil Kollath, Vinayaraj; Van den Broeck, Freya; Fehér, Krisztina; Martins, José C; Luyten, Jan; Traina, Karl; Mullens, Steven; Cloots, Rudi

2015-07-13

Biocompatible inorganic nano- and microcarriers can be suitable candidates for protein delivery. This study demonstrates facile methods of functionalization by using nanoscale linker molecules to change the protein adsorption capacity of hydroxyapatite (HA) powder. The adsorption capacity of bovine serum albumin as a model protein has been studied with respect to the surface modifications. The selected linker molecules (lysine, arginine, and phosphoserine) can influence the adsorption capacity by changing the electrostatic nature of the HA surface. Qualitative and quantitative analyses of linker-molecule interactions with the HA surface have been performed by using NMR spectroscopy, zeta-potential measurements, X-ray photoelectron spectroscopy, and thermogravimetric analyses. Additionally, correlations to theoretical isotherm models have been calculated with respect to Langmuir and Freundlich isotherms. Lysine and arginine increased the protein adsorption, whereas phosphoserine reduced the protein adsorption. The results show that the adsorption capacity can be controlled with different functionalization, depending on the protein-carrier selections under consideration. The scientific knowledge acquired from this study can be applied in various biotechnological applications that involve biomolecule-inorganic material interfaces. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A century-long sedimentary record of pesticide use in the Küçükçekmece Lagoon region, Turkey

NASA Astrophysics Data System (ADS)

Unlu, Selma; Alpar, Bedri

2017-04-01

Organochlorine pesticides (OCPs), extensively used for pest and disease control since the 1940s, can be bioaccumulated through food chains and cause adverse impacts on the environment and human health. Their use and manufacture have been banned or restricted in the 1980s in most countries. OCPs have a strong affinity to suspended particles, so they subsequently settle down into sediment. Sediments in aquatic systems could also become another source of OCPs, due to water turbulence, dredging and bioturbation. Piston coring recoveries in the Küçükçekmece Lagoon, a coastal wetland protected from the sea by a narrow strip of sandbar in the western part of Istanbul, indicated mostly homogeneous and seasonally layered lithological textures throughout the cores. The sediment profiles seem to be not subjected serious physical rearrangements, so that there is the opportunity for deposit preservation. The core 5 was analysed to delineate the vertical variations of selected organochlorine pesticide (OCPs) residues using gas chromatography (GC-ECD/MS) and dated using 210Pb and 137Cs dating methods. The total OCP residues ranged from 3.0 to 498.7 ng/g-dw, with the median concentration of 64 ng/g-dw, while α-HCH and p,p'-DDT were dominant OCPs, with maximum concentrations of 469.3 and 71.0 ng/g dw, respectively. Dated concentration-depth profiles suggest that highest inputs occurred in the first half of last century and followed by significant decreases. Despite the restriction in use, the prevalent nature of OCPs in the core sediment reflects the persistent nature and the lipophilic character of these contaminants. The major sources of the HCHs were from the use of technical HCHs. Sources DDTs identified by specific molecular ratios indicated that DDT residues were mainly originated from technical DDTs from both historical usage and recent input. The organochlorine pesticide residues did demonstrate markedly different distributions reflecting different agricultural and domestic usage in the region. Even though the risk of sediment toxicity was not so high according to the sediment quality guidelines, the bioaccumulation and the amplification of toxic organic pollutants may have major implications. Therefore, this study on the residual levels of the OCPs, their temporal distributions and the source analysis will not only contribute to understanding the environmental behaviour but also provide the necessary theoretical basis for persistent toxic pollution prevention and lake environmental management. This research was supported by the Scientific and Technological Council of Turkey (112Y104) and the Research Funds of Istanbul University (byp-22247).

Bacterial vaginosis modifies the association between hormonal contraception and HIV acquisition

PubMed Central

Haddad, Lisa B.; Wall, Kristin M.; Kilembe, William; Vwalika, Bellington; Khu, Naw H.; Brill, Ilene; Chomba, Elwyn; Tichacek, Amanda; Allen, Susan

2018-01-01

Objective: To examine bacterial vaginosis as an effect modifier for the association between hormonal contraception and incident HIV infection. Design: Serodiscordant couples enrolled in an open longitudinal cohort in Lusaka, Zambia from 1994 to 2012. This analysis was restricted to couples with an HIV-positive man enrolled between1994 and 2002 when a quarterly genital tract examination and HIV testing was performed. Methods: Multivariate Cox models evaluated the association between contraceptive method and HIV-acquisition, stratified by time-varying bacterial vaginosis status. Results: Among 564 couples contributing 1137.2 couple-years of observation, bacterial vaginosis was detected at 15.5% of study visits. Twenty-two of 106 seroconversions occurred during intervals after bacterial vaginosis was detected [12 on no method/nonhormonal method (nonhormonal contraception), two on injectables, eight on oral contraceptive pills (OCPs)]. Unadjusted seroincidence rates per 100 couple-years for nonhormonal contraception, injectable, and OCP users, respectively, during intervals with bacterial vaginosis were 8.3, 20.8, and 31.0 and during intervals without bacterial vaginosis were 8.2, 9.7, and 12.3. In the bacterial vaginosis-positive model, there was a significant increase in incident HIV among those using injectables (adjusted hazard ratio, aHR 6.55, 95% CI 1.14–37.77) and OCPs (aHR 5.20, 95% CI 1.68–16.06) compared with nonhormonal contraception. Hormonal contraception did not increase the hazard of HIV acquisition in bacterial vaginosis-negative models. These findings persisted in sensitivity analyses whenever all covariates from the nonstratified model previously published were included, whenever other genital tract findings were excluded from the model and with the addition of condom-less sex and sperm on wet-prep. Conclusion: Future research should consider a potential interaction with bacterial vaginosis whenever evaluating the impact of hormonal contraception on HIV acquisition. PMID:29334545

A novel astaxanthin-binding photooxidative stress-inducible aqueous carotenoprotein from a eukaryotic microalga isolated from asphalt in midsummer.

PubMed

Kawasaki, Shinji; Mizuguchi, Keisuke; Sato, Masaru; Kono, Tetsuya; Shimizu, Hirofumi

2013-07-01

Water-soluble orange carotenoid proteins (OCPs) that bind 3'-hydroxyechinenone are found in cyanobacteria, and are thought to play a key role in photoprotection. The distribution of OCPs in eukaryotes remains largely unknown. In this study, we identified a novel OCP that predominantly binds astaxanthin from a eukaryotic microalga, strain Ki-4, isolated from a dry surface of heated asphalt in midsummer. A purified astaxanthin-binding OCP, named AstaP, shows high solubility in water with an absorption peak at 484 nm, and possesses a heat-stable activity that quenches singlet oxygen. The deduced amino acid sequence of AstaP comprises an N-terminal hydrophobic signal peptide, fasciclin domains found in secreted and cell surface proteins, and N-linked glycosylation sites, the first example of a carotenoprotein among fasciclin family proteins. AstaP homologs of unknown function are distributed mainly in organisms from the hydrosphere, such as marine bacteria, cyanobacteria, sea anemone and eukaryotic microalgae; however, AstaP exhibits a unique extraordinarily high isoelectric point (pI) value among homologs. The gene encoding AstaP, as well as the AstaP peptide, is expressed abundantly under conditions of dehydration and salt stress in conjunction with high light exposure. As a unique aqueous carotenoprotein, AstaP will provide a novel function of OCPs in protection against extreme photooxidative stresses.

Organochlorine pesticides in surface soils from obsolete pesticide dumping ground in Hyderabad City, Pakistan: contamination levels and their potential for air-soil exchange.

PubMed

Alamdar, Ambreen; Syed, Jabir Hussain; Malik, Riffat Naseem; Katsoyiannis, Athanasios; Liu, Junwen; Li, Jun; Zhang, Gan; Jones, Kevin C

2014-02-01

This study was conducted to examine organochlorine pesticides (OCPs) contamination levels in the surface soil and air samples together with air-soil exchange fluxes at an obsolete pesticide dumping ground and the associated areas from Hyderabad City, Pakistan. Among all the sampling sites, concentrations of OCPs in the soil and air samples were found highest in obsolete pesticide dumping ground, whereas dominant contaminants were dichlorodiphenyltrichloroethane (DDTs) (soil: 77-212,200 ng g(-1); air: 90,700 pg m(-3)) and hexachlorocyclohexane (HCHs) (soil: 43-4,090 ng g(-1); air: 97,400 pg m(-3)) followed by chlordane, heptachlor and hexachlorobenzene (HCB). OCPs diagnostic indicative ratios reflect historical use as well as fresh input in the study area. Moreover, the air and soil fugacity ratios (0.9-1.0) at the dumping ground reflecting a tendency towards net volatilization of OCPs, while at the other sampling sites, the fugacity ratios indicate in some cases deposition and in other cases volatilization. Elevated concentrations of DDTs and HCHs at pesticide dumping ground and its surroundings pose potential exposure risk to biological organisms, to the safety of agricultural products and to the human health. Our study thus emphasizes the need of spatio-temporal monitoring of OCPs at local and regional scale to assess and remediate the future adverse implications. © 2013.

Sources and characteristics of organochlorine pesticides in the soil and sediment along the Kaidu-Peacock River, Northwest of China

NASA Astrophysics Data System (ADS)

Chen, Wei; Qi, Shihua; Peng, Fei; Qu, Chengkai; Zhang, Yuan; Xing, Xinli; Zhang, Jiaquan

2016-04-01

Organochlorine pesticides (OCPs) are a sub-group of persistent organic pollutants (POPs), which have raised the concerns from researchers all around the world for several decades. But very little research has been conducted on POPs in the arid zone of Northwest China. More than 100 soil and sediment samples were collected from Kaidu-Peacock River of Xinjiang, Northwest of China, to investigate the organochlorine pesticides (OCPs) in this region analysed by the gas chromatograph equipped with a mass selective detector (GC-MSD). Our pre-study in 2006 (Chen et al. 2011) in the same region, showed that OCPs except o,p'-DDT were detected in sediments from the Peacock River. Similar results were found in the whole river catchment in this investigation. DDTs, HCHs, chlordanes and endosulfans were the dominant OCPs residual in the soil and sediments. This study confirmed that POPs, such as OCPs in this region were contributed to by both local emissions and long-term atmospheric transport and may pose risks to human health and the ecosystem. Chen, W., Jing, M., Bu, J., Ellis Burnet, J., Qi, S., Song, Q., Ke, Y., Miao, J., Liu, M. & Yang, C. (2011) Organochlorine pesticides in the surface water and sediments from the Peacock River Drainage Basin in Xinjiang, China: a study of an arid zone in Central Asia. Environmental Monitoring and Assessment, 177, 1-21.

Application of hard sphere perturbation theory for thermodynamics of model liquid metals

NASA Astrophysics Data System (ADS)

Mon, K. K.

2001-06-01

Hard sphere perturbation theory (HSPT) has contributed toward the fundamental understanding of dense fluids for over 30 years. In recent decades, other techniques have been more popular. In this paper, we argue for the revival of hard sphere perturbation theory for the study of thermodynamics of dense liquid in general, and in liquid metal in particular. The weakness of HSPT is now well understood, and can be easily overcome by using a simple convenient Monte Carlo method to calculate the intrinsic error of HSPT free energy density. To demonstrate this approach, we consider models of liquid aluminum and sodium. We obtain the intrinsic error of HSPT with the Monte Carlo method. HSPT is shown to provide a lower free energy upper bound than one-component plasma (OCP) for alkali metals and polyvalent metals. We are thus able to provide insight into the long standing observation that a OCP is a better reference system than a HS for alkali metals.

A histidine residue of the influenza virus hemagglutinin controls the pH dependence of the conformational change mediating membrane fusion.

PubMed

Mair, Caroline M; Meyer, Tim; Schneider, Katjana; Huang, Qiang; Veit, Michael; Herrmann, Andreas

2014-11-01

The conformational change of the influenza virus hemagglutinin (HA) protein mediating the fusion between the virus envelope and the endosomal membrane was hypothesized to be induced by protonation of specific histidine residues since their pKas match the pHs of late endosomes (pK(a) of ∼ 6.0). However, such critical key histidine residues remain to be identified. We investigated the highly conserved His184 at the HA1-HA1 interface and His110 at the HA1-HA2 interface of highly pathogenic H5N1 HA as potential pH sensors. By replacing both histidines with different amino acids and analyzing the effect of these mutations on conformational change and fusion, we found that His184, but not His110, plays an essential role in the pH dependence of the conformational change of HA. Computational modeling of the protonated His184 revealed that His184 is central in a conserved interaction network possibly regulating the pH dependence of conformational change via its pKa. As the propensity of histidine to get protonated largely depends on its local environment, mutation of residues in the vicinity of histidine may affect its pK(a). The HA of highly pathogenic H5N1 viruses carries a Glu-to-Arg mutation at position 216 close to His184. By mutation of residue 216 in the highly pathogenic as well as the low pathogenic H5 HA, we observed a significant influence on the pH dependence of conformational change and fusion. These results are in support of a pK(a)-modulating effect of neighboring residues. The main pathogenic determinant of influenza viruses, the hemagglutinin (HA) protein, triggers a key step of the infection process: the fusion of the virus envelope with the endosomal membrane releasing the viral genome. Whereas essential aspects of the fusion-inducing mechanism of HA at low pH are well understood, the molecular trigger of the pH-dependent conformational change inducing fusion has been unclear. We provide evidence that His184 regulates the pH dependence of the HA conformational change via its pK(a). Mutations of neighboring residues which may affect the pK(a) of His184 could play an important role in virus adaptation to a specific host. We suggest that mutation of neighboring residue 216, which is present in all highly pathogenic phenotypes of H5N1 influenza virus strains, contributed to the adaptation of these viruses to the human host via its effect on the pKa of His184. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Maillard Conjugation of Sodium Alginate to Whey Protein for Enhanced Resistance to Surfactant-Induced Competitive Displacement from Air-Water Interfaces.

PubMed

Cai, Bingqing; Saito, Anna; Ikeda, Shinya

2018-01-24

Whey protein adsorbed to an interface forms a viscoelastic interfacial film but is displaced competitively from the interface by a small-molecule surfactant added afterward. The present study evaluated the impact of the covalent conjugation of high- or low-molecular-weight sodium alginate (HA or LA) to whey protein isolate (WPI) via the Maillard reaction on the ability of whey protein to resist surfactant-induced competitive displacement from the air-water interface. Surfactant added after the pre-adsorption of conjugate to the interface increased surface pressure. At a given surface pressure, the WPI-LA conjugate showed a significantly higher interfacial area coverage and lower interfacial film thickness compared to those of the WPI-HA conjugate or unconjugated WPI. The addition of LA to the aqueous phase had little effect on the interfacial area and thickness of pre-adsorbed WPI. These results suggest the importance of the molecular weight of the polysaccharide moiety in determining interfacial properties of whey protein-alginate conjugates.

Selected Organochlorines in Human Blood and Urine in the South of the Russian Far East.

PubMed

Tsygankov, Vasiliy Yu; Khristoforova, Nadezhda K; Lukyanova, Olga N; Boyarova, Margarita D; Kiku, Pavel F; Yarygina, Marina V

2017-10-01

The trace OCP concentrations, such as α-, β-, and γ-HCH, DDT and its metabolites (DDD and DDE) in blood and urine of residents from the south of the Russian Far East was revealed. A large range of OCPs was found in the urine: α- and γ-isomers of HCH, DDT and DDE. The only β-HCH was detected in the blood; this indicates its persistence and the difficulty of excretion this substance from the organism. The total trace OCP concentration, found in the biological fluids of residents of the south of the Russian Far East, providing further evidence that these organic contaminants persist in the environment.

First ecotoxicological assessment assay in a hydroelectric reservoir: the Lake Taabo (Côte d'Ivoire).

PubMed

Roche, Hélène; Tidou, Abiba

2009-03-01

Organochlorine pesticides (OCPs) contamination was assessed in marketable species, two fishes (tilapia and catfish) and a prawn from the Lake Taabo (Côte d'Ivoire). Lindane and endosulfan were the main contaminants, suggesting their current use. DDT, endrin, heptachlor plus traces of chlordane, aldrin and fipronil were also detected. In fishes and in prawns, enzymatic biomarkers exhibited significant correlations with OCPs levels, showing the feasibility of a biomonitoring. The transfer of OCPs along the aquatic food web and their immunosuppressive effects in human are discussed. This preliminary study highlights that the pesticide contamination was concomitant with the increase in infectious diseases in the bordering population of this African lake.

Persistent organic pollutants in the natural environments of the city of Bratsk (Irkutsk Oblast): Levels and risk assessment

NASA Astrophysics Data System (ADS)

Mamontova, E. A.; Tarasova, E. N.; Mamontov, A. A.

2014-11-01

The contents of persistent organic pollutants (POPs)—polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs)—in the natural environments of an industrial city (Bratsk) of Irkutsk oblast have been studied. Features of the spatial and seasonal distribution of the PCBs and OCPs in the soils and the atmospheric air have been revealed. The structure of the homological and congeneric composition of the PCBs in the soils and the atmospheric air has been shown. Parameters of the carcinogenic and noncarcinogenic risks for human health from the impact of the PCBs and OCPs present in the soils and the atmospheric air have been determined.

Fuels and fire behavior in chipped and unchipped plots: implications for land management near the wildland/urban interface

Treesearch

Jeff S. Glitzenstein; Donna R. Streng; Gary L. Achtemeier; Luke P. Naeher; Dale D. Wade

2006-01-01

Fire behavior was measured and modeled from eight 1 ha experimental plots located in the Francis Marion National Forest, South Carolina, during prescribed burns on February 12 and February 20, 2003. Four of the plots had been subjected to mechanical chipping during 2002 to remove woody understory growth and to reduce large downed woody debris from the aftermath of...

TISSUE DISTRIBUTION OF PCBS AND ORGANOCHLORINE PESTICIDES IN ALASKAN NORTHERN FUR SEALS: COMPARISON OF VARIOUS CONGENER CLASSIFICATION SCHEMES

USDA-ARS?s Scientific Manuscript database

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) are believed to adversely affect reproduction and cause health problems in Pinnipeds 1-4. In this study, 145 PCB congeners and OCPs were analyzed in 10 juvenile male northern fur seals, Callorhinus ursinus, collected from Alaskan...

Try Out a New OD Approach: Measuring Climate and Communication with the Organizational Communication Profile.

ERIC Educational Resources Information Center

Peterson, Brent D.; Pace, R. Wayne

The Organizational Communication Profile (OCP) provides a way to survey organization member attitudes, perceptions, expectations, and degree of satisfaction with the manner in which information is handled within the organization. Although the OCP is relatively easy to administer and interpret, the instrument has a complex design and provides…

Dynamic Photoelectrochemical Device Using an Electrolyte-Permeable NiO x/SiO2/Si Photocathode with an Open-Circuit Potential of 0.75 V.

PubMed

Jung, Jin-Young; Yu, Jin-Young; Lee, Jung-Ho

2018-03-07

As a thermodynamic driving force obtained from sunlight, the open-circuit potential (OCP) in photoelectrochemical cells is typically limited by the photovoltage ( V ph ). In this work, we establish that the OCP can exceed the value of V ph when an electrolyte-permeable NiO x thin film is employed as an electrocatalyst in a Si photocathode. The built-in potential developed at the NiO x /Si junction is adjusted in situ according to the progress of the NiO x hydration for the hydrogen evolution reaction (HER). As a result of decoupling of the OCP from V ph , a high OCP value of 0.75 V (vs reversible hydrogen electrode) is obtained after 1 h operation of HER in an alkaline electrolyte (pH = 14), thus outperforming the highest value (0.64 V) reported to date with conventional Si photoelectrodes. This finding might offer insight into novel photocathode designs such as those based on tandem water-splitting systems.

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in harbor sediments from Sea Lots, Port-of-Spain, Trinidad and Tobago.

PubMed

Mohammed, Azad; Peterman, Paul; Echols, Kathy; Feltz, Kevin; Tegerdine, George; Manoo, Anton; Maraj, Dexter; Agard, John; Orazio, Carl

2011-06-01

Concentrations of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were determined in nearshore marine surficial sediments from three locations in Trinidad. Sediments were sampled at Sea Lots on the west coast, in south Port-of-Spain Harbor, south of Sea Lots at Caroni Lagoon National Park, and on Trinidad's east coast at Manzanilla. Total PCB concentrations in Sea Lots sediments ranged from 62 to 601ng/g (dry weight {dw}), which was higher than at Caroni and Manzanilla, 13 and 8ng/g dw, respectively. Total OCP concentrations at Sea Lots were ranged from 44.5 to 145ng/g dw, compared with 13.1 and 23.8n/g (dw), for Caroni and Manzanilla respectively. The concentrations of PCBs and of some OCPs in sediments from Sea Lots were above the Canadian interim sediment quality guidelines. To date, this data is the first report on the levels of PCBs and other organochlorine compounds from Trinidad and Tobago. Copyright © 2011 Elsevier Ltd. All rights reserved.

Optimization of in-cell accelerated solvent extraction technique for the determination of organochlorine pesticides in river sediments.

PubMed

Duodu, Godfred Odame; Goonetilleke, Ashantha; Ayoko, Godwin A

2016-04-01

Organochlorine pesticides (OCPs) are ubiquitous environmental contaminants with adverse impacts on aquatic biota, wildlife and human health even at low concentrations. However, conventional methods for their determination in river sediments are resource intensive. This paper presents an approach that is rapid and also reliable for the detection of OCPs. Accelerated Solvent Extraction (ASE) with in-cell silica gel clean-up followed by Triple Quadrupole Gas Chromatograph Mass Spectrometry (GCMS/MS) was used to recover OCPs from sediment samples. Variables such as temperature, solvent ratio, adsorbent mass and extraction cycle were evaluated and optimized for the extraction. With the exception of Aldrin, which was unaffected by any of the variables evaluated, the recovery of OCPs from sediment samples was largely influenced by solvent ratio and adsorbent mass and, to some extent, the number of cycles and temperature. The optimized conditions for OCPs extraction in sediment with good recoveries were determined to be 4 cycles, 4.5 g of silica gel, 105 °C, and 4:3 v/v DCM: hexane mixture. With the exception of two compounds (α-BHC and Aldrin) whose recoveries were low (59.73 and 47.66% respectively), the recovery of the other pesticides were in the range 85.35-117.97% with precision <10% RSD. The method developed significantly reduces sample preparation time, the amount of solvent used, matrix interference, and is highly sensitive and selective. Copyright © 2015 Elsevier B.V. All rights reserved.

Spatial distribution of organochlorine pesticides (OCPs) and effect of soil characters: a case study of a pesticide producing factory.

PubMed

Zhao, Congcong; Xie, Huijun; Zhang, Jian; Xu, Jingtao; Liang, Shuang

2013-03-01

The distribution and concentration of some organochlorine pesticides (OCPs) in the soil around a pesticide factory in Zibo, China, were examined, including dichlorodiphenyltrichloroethane (DDT) and its metabolites, isomers of hexachlorocyclohexane (HCH) and endosulfan (ENDO). The results showed that the OCPs concentrations were extraordinary high in this region. The concentrations of DDTs, HCHs, and ENDO were measured in the range of 0.775-226.711, 0.248-42.838, and 0.081-1.644 mg kg(-1), respectively. DDT and its isomers were identified to be the dominate contaminants in most of the sampling sites. In the vertical direction, the distribution pattern of the total OCPs was in order of DDTs, HCHs, and ENDO in the 0-20 cm, but in 20-40 and 40-60 cm the trends were unobvious. Although no recent input occurred in most areas, the residues of OCPs remained in deep soil due to their persistence. Unlike ENDO, DDTs and HCHs appeared to have the similar property in terms of not only the migration pattern in soil, but also the relationship to the same dominant impact factor (i.e. organic matter). DDTs and HCHs were affected positively by the organic matter, whereas ENDO was affected negatively. Due to the interrelationship among various impact factors, the spatial distribution of pesticides in the soil was considered to be a combined result. Copyright © 2012 Elsevier Ltd. All rights reserved.

Preparation of C18 composite solid-phase microextraction fiber and its application to the determination of organochlorine pesticides in water samples.

PubMed

Li, Siyan; Lu, Chengwei; Zhu, Fang; Jiang, Ruifen; Ouyang, Gangfeng

2015-05-11

In this work, a C18 composite solid-phase microextraction (SPME) fiber was prepared with a new method and applied to the analysis of organochlorine pesticides (OCPs) in water sample. A stainless steel wire (o.d. 127 μm) was used as the substrate, and a mixture of the C18 particle (3.5 μm) and the 184 silicone was used as the coating material. During the process of fiber preparation, a section of capillary column was used to fix the mixture onto the stainless steel wire and to ensure the constant of coating thickness. The prepared fiber showed excellent thermal stability and solvent resistance. By coupling with gas chromatography-mass spectrometry (GC-MS), the fiber exhibited wide linearity (2-500 ng L(-1)) and good sensitivity for the determination of six OCPs in water samples, the OCPs tested included hexachlorobezene, trans-chlordane, cis-chlordane, o,p-DDT, p,p-DDT and mirex. Not only the extraction performance of the newly prepared fiber was more than seven times higher than those of commercial fibers, the limits of detections (LODs) (0.059-0.151 ng L(-1)) for OCPs achieved under optimized conditions were also lower than those of reported SPME methods. The fiber was successfully applied to the determination of OCPs in real water samples by using developed SPME-GC-MS method. Copyright © 2015 Elsevier B.V. All rights reserved.

Organochlorine pesticides across the tributaries of River Ravi, Pakistan: Human health risk assessment through dermal exposure, ecological risks, source fingerprints and spatio-temporal distribution.

PubMed

Baqar, Mujtaba; Sadef, Yumna; Ahmad, Sajid Rashid; Mahmood, Adeel; Li, Jun; Zhang, Gan

2018-03-15

This study monitored the human health risks through dermal exposure, hazardous risks to ecological integrity, contamination levels, spatio-temporal distribution, and congener specific analysis of organochlorine pesticides (OCPs) across River Ravi and its three northern tributaries (Nullah Bein, Nullah Basanter and Nullah Deg). The residual levels of OCPs isomers were screened for water (n=54) and surface sediment (n=54) samples from twenty seven sampling sites in two alternate seasons (pre-monsoon and post-monsoon). The ∑OCPs concentrations ranged from 13.61 to 1992.18ng/g dry weight and 12.89 to 128.16ng/L with predominance of β-endosulfan and p,p'-DDT in sediment and water matrixes, respectively. Distribution pattern revealed significantly higher concentrations in upstream and midstream, suggesting considerable transboundary OCPs pollution. Calculated ratios of α-HCH/γ-HCH, o,p'-DDT/p,p'-DDT, (DDE+DDD)/∑DDTs and cis/trans-chlordane for water and sediments identified the fresh addition of lindane, technical DDTs and chlordane in the study area. Risk quotient (RQ) based ecological risk was found to be >1 at all studied streams during both seasons and elucidates higher risks for endosulfan (α-endosulfan) and endrin. Human health risk assessment indicated absence of hazardous (non-carcinogenic) risk through bathing in studied streams; as the hazard index values ranged from 1.09E-05 to 2.48E-02 (acceptable limit; <1). However, the calculated carcinogenic risk possessed by OCPs through dermal exposure ranged from 1.39E-10 to 1.98E-05 that highlighted the considerable carcinogenic risk associated to aldrin, dieldrin, p,p'-DDT and β-endosulfan at certain studied sites. Therefore, the high levels of ecological risk and carcinogenic human health risk had emphasized an immediate elimination of ongoing OCPs addition in the studied area. Copyright © 2017 Elsevier B.V. All rights reserved.

Bioaccumulation and risk assessment of organochlorine pesticides in fish from a global biodiversity hotspot: iSimangaliso Wetland Park, South Africa.

PubMed

Buah-Kwofie, Archibold; Humphries, Marc S; Pillay, Letitia

2018-04-15

Organochlorine pesticides (OCPs) have been used extensively in the eastern regions of South Africa for agricultural and malaria control purposes, yet few data exist on the local environmental and social impacts of these compounds. Such issues have become of increasing concern in the iSimangaliso World Heritage Site, where the continued use of OCPs may pose risks to several sensitive and protected species. This study was designed to examine the bioaccumulation of OCPs in two common fish species, Oreochromis mossambicus (Mozambique tilapia) and Clarias gariepinus (African sharptooth catfish) from iSimangaliso Wetland Park. These species are targeted by local subsistence fishermen and sustain substantial bird and crocodile populations. Our findings indicate widespread contamination of the aquatic environment, with ΣOCP fish tissue concentrations in the range of 6907-8740ngg -1 lw and 2953-5874ngg -1 lw for C. gariepinus and O. mossambicus, respectively. HCHs (471-1570ngg -1 lw), DDTs (645-2399ngg -1 lw), drin-related residues (589-1960ngg -1 lw), chlor-related residues (455-2162ngg -1 lw) and endosulfans (457-1495ngg -1 lw) were detected in all tissue samples. Concentrations detected in the majority of samples exceeded European Commission maximum residue limits and a health risk assessment indicated potential dietary risk associated with exposure to heptachlor, heptachlor epoxide and dieldrin. This study represents the first investigation into OCP bioaccumulation in fish species from iSimangaliso Wetland Park. Our findings highlight the need for more detailed investigations into the bioaccumulation and ecotoxicological effects of these contaminants in the food web and the associated risks to local ecosystems and human health. High levels of OCPs detected in two common fish species at iSimangaliso Wetland Park highlight potential human health and ecotoxicological threats to a globally important biodiversity conservation hotspot. Copyright © 2017 Elsevier B.V. All rights reserved.

Long-range atmospheric transport of persistent organochlorinated compounds from south and mainland south-eastern Asia to a remote mountain site in south-western China.

PubMed

Xu, Yue; Zhang, Gan; Li, Jun; Chakraborty, Paromita; Li, Hua; Liu, Xiang

2011-11-01

A range of organochlorinated compounds have been consumed in China, India and the countries of mainland southeast Asia (MSA). Considering their persistence in the environment and ability in long-range atmospheric transport (LRAT), the potential outflow of these compounds from this region is therefore of great concern in the context of the global distribution of toxic chemicals. As part of a monitoring campaign aimed at investigating the LRAT of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) from southern China, MSA and northern India, atmospheric levels of OCPs and PCBs were measured once a week from October 2005 through December 2006 at Tengchong Mountain (TM), a remote site located in south-western China. The average concentrations of OCPs were found to be higher than those in other remote stations in the Arctic and the Tibetan plateau, except for α-hexachlorocyclohexane (α-HCH). A high level of β-HCH and low α-HCH/β-HCH ratio was attributed to an accidental release of β-HCH from unknown sources, besides obvious evidence of lindane (γ-HCH) and technical HCH usage. Temporal variations of chlordanes and endosulfan were related to the usage pattern of these compounds, as well as LRAT. In contrast, dichlorodiphenyltrichloroethane (DDT) exhibited a relatively minor seasonal variation. The OCP levels at the monitoring site were found to be related to the air parcel back trajectories on the basis of four distinct clusters. Elevated levels of HCHs and DDTs were observed when air parcels originated from northern India where considerable OCP usage was reported recently, while high levels of γ-HCH and TC (trans-chlordane) were mainly associated with air masses from southern China and northern MSA. The study highlighted the high background level of OCPs as well as their temporal patterns of trans-boundary LRAT in the MSA region.

Randomized Controlled Trial of Preconception Interventions in Infertile Women With Polycystic Ovary Syndrome

PubMed Central

Dodson, William C.; Kris-Etherton, Penny M.; Kunselman, Allen R.; Stetter, Christy M.; Williams, Nancy I.; Gnatuk, Carol L.; Estes, Stephanie J.; Fleming, Jennifer; Allison, Kelly C.; Sarwer, David B.; Coutifaris, Christos; Dokras, Anuja

2015-01-01

Context: Lifestyle modification is recommended in women with polycystic ovary syndrome (PCOS) prior to conception but there are few randomized trials to support its implementation or benefit. Objective: This study aimed to determine the relative efficacy of preconception intervention on reproductive and metabolic abnormalities in overweight/obese women with PCOS. Design, Setting, and Participants: This was a randomized controlled trial of preconception and infertility treatment at Academic Health Centers in women with infertility due to PCOS, age 18–40 y and body mass index 27–42 kg/m2. Intervention: Women were randomly assigned to receive either 16 weeks of 1) continuous oral contraceptive pills (OCPs) (ethinyl estradiol 20 mcg/1 mg norethindrone acetate) (“OCP”); 2) lifestyle modification consisting of caloric restriction with meal replacements, weight loss medication (either sibutramine, or orlistat), and increased physical activity to promote a 7% weight loss (“Lifestyle”); or 3) combined treatment with both OCP and lifestyle modification (“Combined”). After preconception intervention, women underwent standardized ovulation induction with clomiphene citrate and timed intercourse for four cycles. Pregnancies were followed with trimester visits until delivery. Main Outcome Measures: Weight, ovulation, and live birth were measured. Results: We consented 216 and randomly assigned 149 women (Lifestyle: n = 50; OCP: n = 49; Combined: n = 50). We achieved significant weight loss with both Lifestyle (mean weight loss, −6.2%; 95% confidence interval (CI), −7.4–−5.0; and Combined (mean weight loss, −6.4%; 95% CI, −7.6–−5.2) compared with baseline and OCP (both P < .001). There was a significant increase in the prevalence of metabolic syndrome at the end of preconception treatment compared with baseline within OCP (odds ratio [OR, 2.47; 95% CI, 1.42–4.27) whereas no change in metabolic syndrome was detected in the Lifestyle (OR, 1.18; 95% CI, 0.63–2.19) or Combined (OR, 0.72; 95% CI, 0.44–1.17) groups. Cumulative ovulation rates were superior after weight loss: OCP, 46%; Lifestyle, 60%; and Combined, 67% (P < .05). Live birth rates were OCP, 12%; Lifestyle, 26%; and Combined, 24% (P = .13). Conclusions: A preconception weight loss intervention eliminates the adverse metabolic oral contraceptive effects and, compared with oral contraceptive pretreatment, leads to higher ovulation rates. PMID:26401593

Evaluating organochlorine pesticide residues in the aquatic environment of the Lake Naivasha River basin using passive sampling techniques.

PubMed

Abbasi, Yasser; Mannaerts, Chris M

2018-05-18

Passive sampling techniques can improve the discovery of low concentrations by continuous collecting the contaminants, which usually go undetected with classic and once-off time-point grab sampling. The aim of this study was to evaluate organochlorine pesticide (OCP) residues in the aquatic environment of the Lake Naivasha river basin (Kenya) using passive sampling techniques. Silicone rubber sheet and Speedisk samplers were used to detect residues of α-HCH, β-HCH, γ-HCH, δ-HCH, heptachlor, aldrin, heptachlor epoxide, pp-DDE, endrin, dieldrin, α-endosulfan, β-endosulfan, pp-DDD, endrin aldehyde, pp-DDT, endosulfan sulfate, and methoxychlor in the Malewa River and Lake Naivasha. After solvent extraction from the sampling media, the residues were analyzed using gas chromatography electron capture detection (GC-ECD) for the OCPs and gas chromatography-mass spectrometry (GC-MS) for the PCB reference compounds. Measuring the OCP residues using the silicone rubber samplers revealed the highest concentration of residues (∑OCPs of 81 (± 18.9 SD) μg/L) to be at the Lake site, being the ultimate accumulation environment for surficial hydrological, chemical, and sediment transport through the river basin. The total OCP residue sums changed to 71.5 (± 11.3 SD) μg/L for the Middle Malewa and 59 (± 12.5 SD) μg/L for the Upper Malewa River sampling sites. The concentration sums of OCPs detected using the Speedisk samplers at the Upper Malewa, Middle Malewa, and the Lake Naivasha sites were 28.2 (± 4.2 SD), 31.3 (± 1.8 SD), and 34.2 (± 6.4 SD) μg/L, respectively. An evaluation of the different pesticide compound variations identified at the three sites revealed that endosulfan sulfate, α-HCH, methoxychlor, and endrin aldehyde residues were still found at all sampling sites. However, the statistical analysis of one-way ANOVA for testing the differences of ∑OCPs between the sampling sites for both the silicone rubber sheet and Speedisk samplers showed that there was no significant difference from the Upper Malewa to the Lake site (P < 0.05). Finally, the finding of this study indicated that continued monitoring of pesticides residues in the catchment remains highly recommended.

Induction Plasma Sprayed Nano Hydroxyapatite Coatings on Titanium for Orthopaedic and Dental Implants

PubMed Central

Roy, Mangal; Bandyopadhyay, Amit; Bose, Susmita

2011-01-01

This paper reports preparation of a highly crystalline nano hydroxyapatite (HA) coating on commercially pure titanium (Cp-Ti) using inductively coupled radio frequency (RF) plasma spray and their in vitro and in vivo biological response. HA coatings were prepared on Ti using normal and supersonic plasma nozzles at different plate powers and working distances. X-ray diffraction (XRD) and Fourier transformed infrared spectroscopic (FTIR) analysis show that the normal plasma nozzle lead to increased phase decomposition, high amorphous calcium phosphate (ACP) phase formation, and severe dehydroxylation of HA. In contrast, coatings prepared using supersonic nozzle retained the crystallinity and phase purity of HA due to relatively short exposure time of HA particles in the plasma. In addition, these coatings exhibited a microstructure that varied from porous and glassy structure at the coating-substrate interface to dense HA at the top surface. The microstructural analysis showed that the coating was made of multigrain HA particles of ~200 nm in size, which consisted of recrystallized HA grains in the size range of 15– 20 nm. Apart from the type of nozzle, working distance was also found to have a strong influence on the HA phase decomposition, while plate power had little influence. Depending on the plasma processing conditions, a coating thickness between 300 and 400 μm was achieved where the adhesive bond strengths were found to be between 4.8 MPa to 24 MPa. The cytotoxicity of HA coatings was examined by culturing human fetal osteoblast cells (hFOB) on coated surfaces. In vivo studies, using the cortical defect model in rat femur, evaluated the histological response of the HA coatings prepared with supersonic nozzle. After 2 weeks of implantation, osteoid formation was evident on the HA coated implant surface, which could indicate early implant- tissue integration in vivo. PMID:21552358

Inflammatory-metabolic parameters in obese and nonobese normoandrogenemic polycystic ovary syndrome during metformin and oral contraceptive treatment.

PubMed

Kilic, Sevtap; Yilmaz, Nafiye; Zulfikaroglu, Ebru; Erdogan, Gokcen; Aydin, Murat; Batioglu, Sertac

2011-09-01

Our aim was to evaluate the optimal treatment strategy addressing cardiovascular risk in obese and nonobese patients with polycystic ovary syndrome (PCOS). We planned a prospectıve randomized clinical study. Normoandrogenemic and oligoamenorrheic women with PCOS and impaired glucose tolerance (n = 96) were enrolled in the study. Six months of treatment with metformin HCL or oral contraceptive pills (OCPs) were given to the patients. Group 1 were obese and receiving metformin. Group 2 were obese and receiving OCPs. Group 3 were nonobese and receiving metformin, and Group 4 were nonobese receiving OCPs. ADMA, homocysteine, high sensitive C-reactive protein (hs-CRP) and homeostasis model assessment estimate of insulin resistance (HOMA-IR) were investigated. ADMA, homocysteine, hs-CRP and HOMA-IR were similar in obese and nonobese groups before the treatment. After 6 months of treatment, a significant decrease was observed in ADMA, homocysteine and HOMA-IR levels in Groups 1 and 3. An increase in ADMA and hs-CRP levels was observed in Groups 2 and 4. In this study, metformin treatment leads to improvement in hormonal and metabolic parameters and decreases ADMA and homocysteine levels possibly independent of BMI. However, the use of oral contraceptives in obese and nonobese patients with PCOS with impaired glucose tolerance increases ADMA and hs-CRP levels and creates an increase in the metabolic risk.

Distribution and health risk assessment of organochlorine pesticides (OCPs) in industrial site soils: a case study of urban renewal in Beijing, China.

PubMed

Yang, Wenrui; Wang, Rusong; Zhou, Chuanbin; Li, Feng

2009-01-01

Abstract A field survey was conducted in a contaminated industrial site of southern Beijing, China to investigate the contents and distribution of the organochlorine pesticides (alpha-, beta-, gamma-, delta-HCH, p,p'-DDT, p,p'-DDE, p,p'-DDD and o,p'-DDT) in the profiles of soil, and a health risk assessment was carried out with CalTOX multimedia exposure model. Results showed that mean concentrations of total hexachlorocyclohexane isomers (HCHs) and total dichlorodiphenyltrichloroethane isomers (DDXs) in soils were in the range of 13.20-148.71 mg/kg, and 3.02-67.43 mg/kg, respectively. Organochlorine pesticides (OCPs) content peaked in the surface and declined in soil profile with depth. The amounts of HCHs in three profiles of soil were larger than DDXs. Composition analysis indicated that there was a trend of degradation of OCPs in the site, but the mean of HCHs and DDXs concentration were over the state warning standard limit (HCHs, 0.50 mg/kg; DDXs, 0.50 mg/kg). According to current land use development, health risk assessment with CalTOX and Monte Carlo analysis showed that health risks mainly came from two exposure pathways: dermal uptake and inhalation, and the total risk values all exceeded the general acceptable health risk value (10-6). The sensitivity analysis indicated that five parameters significantly contributed to total risk.

Organochlorine pesticide levels in Ensis siliqua (Linnaeus, 1758) from Ría de Vigo, Galicia (N.W. Spain): influence of season, condition index and lipid content.

PubMed

Carro, Nieves; García, Isabel; Ignacio, María; Mouteira, Ana

2012-04-01

Levels of organochlorine pesticides (OCPs), including ΣDDTs, γ-HCH, HCB, aldrin, isodrin, trans-nonachlor, heptachlor and dieldrin, were determined in the razor clam, Ensis siliqua, collected monthly from February 2003 to April 2004 from the Islas Cíes in Ría de Vigo (Galicia, Spain). The sum of DDTs ranged from 2.17 to 26.9 ng g(-1) dry weight (dw). Principal component analysis showed seasonal trends in the levels of some OCPs (γ-HCH and dieldrin). Pearson correlations (p < 0.05) were observed between OCP levels and the biometric parameters of condition index and body lipids.

Determination of organochlorine pesticides in skins and leather by gas chromatography.

PubMed

Font, J; Marsal, A

1998-06-19

The simultaneous determination of residues of lindane (gamma-HCH) and 10 other organochlorine pesticides (OCPs) in skins and leather was carried out by gas chromatography (GC) with electron-capture detection (ECD). GC with mass spectrometric detection was used to identity confirmation. Samples were extracted with hexane. The extracts were concentrated, and cleaned up on a Florisil column. Dibromooctafluorobiphenyl was added as internal standard. Hide fortifications of 0.5 an d5.0 ppm yielded average lindane recoveries of 98% and 96%, respectively. OCPs was determined in 57 samples of skins purchased from American, European and African countries in 1996-1997. OCPs were not detected in any of the American and European samples. Residues of lindane were found in 56% of African samples.

Organochlorine pesticides and polychlorinated biphenyls levels in human milk from Chelem, Yucatán, México.

PubMed

Rodas-Ortíz, Juan Pablo; Ceja-Moreno, Victor; González-Navarrete, R L; Alvarado-Mejía, Jorge; Rodríguez-Hernández, Marissa E; Gold-Bouchot, Gerardo

2008-03-01

Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in human milk from Chelem, Yucatan, Mexico were analyzed. Relatively high levels of p,p'-DDE, gamma-chlordane, beta-hexacyclohexane (beta-HCH) and PCB congeners 170, 28, and 44 were found. Concentration profiles by OCP groups followed the next order: SigmaDDTs > SigmaChlordanes > SigmaHCHs > SigmaChlorobenzenes > SigmaDrins. Total OCPs showed a decreasing tendency with number of births (primipara and multipara and age ranks) but these differences were not significant. SigmaDDT levels were lower than in other studies in Mexico, but 36% of the samples exceeded the JMPR-FAO/WHO acceptable daily intake (ADI). About 60.53% of samples exceeded the ADI value for heptachlors.

Residues of organochlorine pesticides in soils from the southern Sonora, Mexico.

PubMed

Cantu-Soto, E U; Meza-Montenegro, Maria Mercedes; Valenzuela-Quintanar, A I; Félix-Fuentes, A; Grajeda-Cota, P; Balderas-Cortes, J J; Osorio-Rosas, C L; Acuña-García, G; Aguilar-Apodaca, M G

2011-11-01

Although, the Yaqui and Mayo valleys are the most important agricultural areas in Sonora, there is only limited data of the pesticides residue in soils in these valleys. This study measured the organochlorine pesticides (OCPs) in 234 soil samples (residential and agricultural) from 24 communities. The global results (mean, range) indicated that benzene hexachloride (19.2, ND-938.5 μg g(-1)), endrin (6.6, ND-377.3 μg g(-1)) and DDTs (36.45, ND-679.7 μg g(-1)) were the dominant contaminants. Soil is one of the most important routes of exposure to OCPs in the population of southern Sonora and this study can be used to establish background levels of OCPs.

The architecture of Norway spruce ectomycorrhizae: three-dimensional models of cortical cells, fungal biomass, and interface for potential nutrient exchange.

PubMed

Stögmann, Bernhard; Marth, Andreas; Pernfuß, Barbara; Pöder, Reinhold

2013-08-01

Gathering realistic data on actual fungal biomass in ectomycorrhized fine root systems is still a matter of concern. Thus far, observations on architecture of ectomycorrhizae (ECMs) have been limited to analyses of two-dimensional (2-D) images of tissue sections. This unavoidably causes stereometrical problems that lead to inadequate assumptions about actual size of cells and their arrangement within ECM's functional compartments. Based on extensive morphological investigations of field samples, we modeled the architectural components of an average-sized Norway spruce ECM. In addition to our comprehensive and detailed quantitative data on cell sizes, we studied actual shape and size, in vivo arrangement, and potential nutrient exchange area of plant cortical cells (CCs) using computer-aided three-dimensional (3-D) reconstructions based on semithin serial sections. We extrapolated a factual fungal biomass in ECMs (Hartig net (HN) included) of 1.71 t ha(-1) FW (0.36 t ha(-1) DW) for the top 5 cm of soil for an autochthonous, montane, optimum Norway spruce stand in the Tyrolean Alps. The corresponding potential nutrient exchange area in ECMs including main axes of ECM systems, which is defined as the sum of interfaces between plant CCs and the HN, amounts to at least 3.2 × 10(5) m(2) ha(-1). This is the first study that determines the contribution of the HN to the total fungal biomass in ECMs as well as the quantification of its contact area. Our results may stimulate future research on fungal below-ground processes and their impact on the global carbon cycle.

Long-term time trends in human intake of POPs in the Czech Republic indicate a need for continuous monitoring.

PubMed

Bányiová, Katarína; Černá, Milena; Mikeš, Ondřej; Komprdová, Klára; Sharma, Anežka; Gyalpo, Tenzing; Čupr, Pavel; Scheringer, Martin

2017-11-01

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) from the group of persistent organic pollutants are detected in human tissues years or even decades after their ban. Exposure to PCBs and OCPs can pose risks to human health. In the present study, we calculated the daily intakes of PCBs and OCPs in the Czech population and investigated the long-term trends of human exposure to POPs. Data on POP concentrations from a 16-year period of breast-milk monitoring were used. A toxicokinetic model with consideration of compound-specific elimination half-lives was used to calculate the mothers' daily intake of PCBs and OCPs representing the intake of POPs by all exposure routes. The calculated intakes were compared with dietary intakes calculated by the Czech National Institute of Public Health. The comparison shows good agreement of both intake estimates with decreasing intake trends of POPs in the Czech population in the time period studied. However, several fluctuations with peaks of higher levels were observed in both datasets which are not typical for the period after the ban of use and production of POPs. The available evidence suggests that the increases in chemical concentrations might be caused by food contamination. The calculated intakes of compounds with longer elimination half-lives, such as higher-chlorinated PCBs, were higher in older mothers. This "memory effect" was already observed in other studies and indicates higher exposure in earlier life periods of the mother. Our results suggest that exposure to POPs is still relevant for the Czech population in the period after the ban of the use and production of POPs (post-ban period), especially via food ingestion, though the intake trends are decreasing. Possible food contamination by POPs in the post-ban period requires further assessment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Interfacial characteristics and determination of cohesive and adhesive strength of plasma-coated hydroxyapatite via nanoindentation and microscratch techniques.

PubMed

McManamon, Colm; de Silva, Johann P; Power, John; Ramirez-Garcia, Sonia; Morris, Michael A; Cross, Graham L W

2014-09-30

We investigate the chemical composition and mechanical properties of plasma-deposited hydroxyapatite on grit-blasted Ti-6Al-4V coupons as models of typical prosthetic hip implants. Nanoindentation is used to extract the mechanical properties of the hydroxyapatite (HA) coating and to evaluate the behavior of the material as a function of distance from the interface. A microscratch technique was used to determine parameters of cohesive and adhesive failure of the material that are critical in determining the functionality of these biomedical devices. This delamination method has not been studied in detail before and is usually considered to be unsuitable because of the thickness of the HA and the roughness of the substrate. However, through cross-section analysis of the scratch test, we can determine the point at which the HA delaminates from the substrate. It was concluded that spallation occurs locally, and there is no evidence of gross spallation, indicating that the coating is well adhered to the substrate.

The surface activity of purified ocular mucin at the air-liquid interface and interactions with meibomian lipids.

PubMed

Millar, Thomas J; Tragoulias, Sophia T; Anderton, Philip J; Ball, Malcolm S; Miano, Fausto; Dennis, Gary R; Mudgil, Poonam

2006-01-01

Ocular mucins are thought to contribute to the stability of the tear film by reducing surface tension. The purpose of this study was to compare the effect of different mucins and hyaluronic acid (HA) alone and mixed with meibomian lipids on the surface pressure at an air-liquid interface. A Langmuir trough and Wilhelmy balance were used to measure and compare the surface activity of bovine submaxillary gland mucin (BSM), purified BSM, purified bovine ocular mucin and HA, and mixtures of these with meibomian lipids, phosphatidylcholine, and phosphatidylglycerol. Their appearance at the surface of an air-buffer interface was examined using epifluorescence microscopy. Purified ocular mucin had no surface activity even at concentrations that were 100 times more than normally occur in tears. By contrast, commercial BSM caused changes to surface pressure that were concentration dependent. The surface pressure-area profiles showed surface activity with maximum surface pressures of 12.3-22.5 mN/m depending on the concentration. Purified BSM showed no surface activity at low concentrations, whereas higher concentrations reached a maximum surface pressure of 25 mN/m. HA showed no surface activity, at low or high concentrations. Epifluorescence showed that the mucins were located at the air-buffer interface and changed the appearance of lipid films. Purified bovine ocular mucin and HA have no surface activity. However, despite having no surface activity in their own right, ocular mucins are likely to be present at the surface of the tear film, where they cause an increase in surface pressure by causing a compression of the lipids (a reorganization of the lipids) and alter the viscoelastic properties at the surface.

Gradient nano-engineered in situ forming composite hydrogel for osteochondral regeneration.

PubMed

Radhakrishnan, Janani; Manigandan, Amrutha; Chinnaswamy, Prabu; Subramanian, Anuradha; Sethuraman, Swaminathan

2018-04-01

Fabrication of anisotropic osteochondral-mimetic scaffold with mineralized subchondral zone and gradient interface remains challenging. We have developed an injectable semi-interpenetrating network hydrogel construct with chondroitin sulfate nanoparticles (ChS-NPs) and nanohydroxyapatite (nHA) (∼30-90 nm) in chondral and subchondral hydrogel zones respectively. Mineralized subchondral hydrogel exhibited significantly higher osteoblast proliferation and alkaline phosphatase activity (p < 0.05). Osteochondral hydrogel exhibited interconnected porous structure and spatial variation with gradient interface of nHA and ChS-NPs. Microcomputed tomography (μCT) demonstrated nHA gradation while rheology showed predominant elastic modulus (∼930 Pa) at the interface. Co-culture of osteoblasts and chondrocytes in gradient hydrogels showed layer-specific retention of cells and cell-cell interaction at the interface. In vivo osteochondral regeneration by biphasic (nHA or ChS) and gradient (nHA + ChS) hydrogels was compared with control using rabbit osteochondral defect after 3 and 8 weeks. Complete closure of defect was observed in gradient (8 weeks) while defect remained in other groups. Histology demonstrated collagen and glycosaminoglycan deposition in neo-matrix and presence of hyaline cartilage-characteristic matrix, chondrocytes and osteoblasts. μCT showed mineralized neo-tissue formation, which was confined within the defect with higher bone mineral density in gradient (chondral: 0.42 ± 0.07 g/cc, osteal: 0.64 ± 0.08 g/cc) group. Further, biomechanical push-out studies showed significantly higher load for gradient group (378 ± 56 N) compared to others. Thus, the developed nano-engineered gradient hydrogel enhanced hyaline cartilage regeneration with subchondral bone formation and lateral host-tissue integration. Copyright © 2018 Elsevier Ltd. All rights reserved.

Construction of a Direct Water-Injected Two-Stroke Engine for Phased Direct Fuel Injection-High Pressure Charging Investigations

NASA Technical Reports Server (NTRS)

Somsel, James P.

1998-01-01

The development of a water injected Orbital Combustion Process (OCP) engine was conducted to assess the viability of using the powerplant for high altitude NASA aircraft and General Aviation (GA) applications. An OCP direct fuel injected, 1.2 liter, three cylinder, two-stroke engine has been enhanced to independently inject water directly into the combustion chamber. The engine currently demonstrates low brake specific fuel consumption capability and an excellent power to weight ratio. With direct water injection, significant improvements can be made to engine power, to knock limits/ignition advance timing, and to engine NO(x) emissions. The principal aim of the testing was to validate a cyclic model developed by the Systems Analysis Branch at NASA Ames Research Center. The work is a continuation of Ames' investigations into a Phased Direct Fuel Injection Engine with High Pressure Charging (PDFI-ITPC).

The Production of Porous Hydroxyapatite Scaffolds with Graded Porosity by Sequential Freeze-Casting.

PubMed

Lee, Hyun; Jang, Tae-Sik; Song, Juha; Kim, Hyoun-Ee; Jung, Hyun-Do

2017-03-31

Porous hydroxyapatite (HA) scaffolds with porosity-graded structures were fabricated by sequential freeze-casting. The pore structures, compressive strengths, and biocompatibilities of the fabricated porous HA scaffolds were evaluated. The porosities of the inner and outer layers of the graded HA scaffolds were controlled by adjusting the initial HA contents of the casting slurries. The interface between the dense and porous parts was compact and tightly adherent. The porosity and compressive strengths of the scaffold were controlled by the relative thicknesses of the dense/porous parts. In addition, the porous HA scaffolds showed good biocompatibility in terms of preosteoblast cell attachment and proliferation. The results suggest that porous HA scaffolds with load-bearing parts have potential as bone grafts in hard-tissue engineering.

The Production of Porous Hydroxyapatite Scaffolds with Graded Porosity by Sequential Freeze-Casting

PubMed Central

Lee, Hyun; Jang, Tae-Sik; Song, Juha; Kim, Hyoun-Ee; Jung, Hyun-Do

2017-01-01

Porous hydroxyapatite (HA) scaffolds with porosity-graded structures were fabricated by sequential freeze-casting. The pore structures, compressive strengths, and biocompatibilities of the fabricated porous HA scaffolds were evaluated. The porosities of the inner and outer layers of the graded HA scaffolds were controlled by adjusting the initial HA contents of the casting slurries. The interface between the dense and porous parts was compact and tightly adherent. The porosity and compressive strengths of the scaffold were controlled by the relative thicknesses of the dense/porous parts. In addition, the porous HA scaffolds showed good biocompatibility in terms of preosteoblast cell attachment and proliferation. The results suggest that porous HA scaffolds with load-bearing parts have potential as bone grafts in hard-tissue engineering. PMID:28772735

Carry-over of dietary organochlorine pesticides, PCDD/Fs, PCBs, and brominated flame retardants to Atlantic salmon (Salmo salar L.) fillets.

PubMed

Berntssen, Marc H G; Maage, A; Julshamn, K; Oeye, B E; Lundebye, A-K

2011-03-01

Information on carry-over of contaminants from feed to animal food products is essential for appropriate human risk assessment of feed contaminants. The carry-over of potentially hazardous persistent organic pollutants (POPs) from feed to fillet was assessed in consumption sized Atlantic salmon (Salmo salar). Relative carry-over (defined as the fraction of a certain dietary POP retained in the fillet) was assessed in a controlled feeding trial, which provided fillet retention of dietary organochlorine pesticides (OCPs), dioxins (PCDD/Fs), polychlorinated biphenyls (PCBs), and brominated flame retardants (BFRs). Highest retention was found for OCPs, BFRs and PCBs (31-58%), and the lowest retentions were observed for PCDD/Fs congeners (10-34%). National monitoring data on commercial fish feed and farmed Atlantic salmon on the Norwegian market were used to provide commercially relevant feed-to-fillet transfer factors (calculated as fillet POP level divided by feed POP level), which ranged from 0.4 to 0.5, which is a factor 5-10 times higher than reported for terrestrial meat products. For the OCP with one of the highest relative carry-over, toxaphene, uptake and elimination kinetics were established. Model simulations that are based on the uptake and elimination kinetics gave predicted levels that were in agreement with the measured values. Application of the model to the current EU upper limit for toxaphene in feed (50 μg kg(-1)) gave maximum fillet levels of 22 μg kg(-1), which exceeds the estimated permissible level (21 μg kg(-1)) for toxaphene in fish food samples in Norway. Copyright © 2011 Elsevier Ltd. All rights reserved.

Endothelial function across an oral contraceptive cycle in women using levonorgestrel and ethinyl estradiol.

PubMed

Torgrimson, Britta N; Meendering, Jessica R; Kaplan, Paul F; Minson, Christopher T

2007-06-01

Oral contraceptive pills (OCPs) are a popular contraception method. Currently, lower-dose ethinyl estradiol formulations are most commonly prescribed, although they have been linked to increased arterial vascular risk. The aim of this study was to investigate endothelial function in healthy young women using lower-dose ethinyl estradiol OCPs. We examined flow-mediated, endothelium-dependent and nitroglycerin-mediated, endothelium-independent vasodilation of the brachial artery, comparing two doses of ethinyl estradiol/levonorgestrel OCPs in 15 healthy young women on two study days: once during the active phase and once during the placebo phase of an OCP cycle. Group low dose (LD) (n=7) active pills contained 150 microg levonorgestrel/30 microg ethinyl estradiol versus Group very low dose (VLD) (n=8) with 100 microg levonorgestrel/20 microg ethinyl estradiol. Endothelium-dependent vasodilation was lower during the active phase in Group VLD (5.33 +/- 1.77% vs. 7.23 +/- 2.60%; P=0.024). This phase difference was not observed in Group LD (8.00 +/- 0.970% vs. 7.61 +/- 1.07%; P=0.647). Endothelium-independent vasodilation did not differ between phases in either group. Finally, we measured endothelium-dependent vasodilation in two additional women who received 10 microg of unopposed ethinyl estradiol. Endothelium-dependent vasodilation was increased by unopposed ethinyl estradiol compared with the placebo phase (10.88 +/- 2.34% vs. 6.97 +/- 1.83%). These results suggest that levonorgestrel may antagonize the activity of ethinyl estradiol. Thus both the progestin type and estradiol dose need to be considered when assessing arterial vascular risk of OCP use in women.

Levels and profiles of PCBs and OCPs in marine benthic species from the Belgian North Sea and the Western Scheldt Estuary.

PubMed

Voorspoels, Stefan; Covaci, Adrian; Maervoet, Johan; De Meester, Ingrid; Schepens, Paul

2004-09-01

Various benthic invertebrates (flying crab, common shrimp, and red starfish), small fish (sand goby), benthic flatfish (dab, plaice, and sole) and gadoids (bib and whiting) were collected in the Belgian North Sea and along the Scheldt Estuary, both representing areas impacted by various contaminants to different degrees. The levels of 25 polychlorinated biphenyls (PCBs) and 15 organochlorine pesticides (OCPs), which included penta- and hexachlorobenzene, alpha-, beta-, and gamma-hexachlorocyclohexane isomers, chlordanes, and DDT and metabolites, were determined. Sum of PCBs and OCPs in benthic invertebrates and goby ranged from 1.5 to 280 ng/g wet weight (ww) and from 0.27 to 23 ng/g ww, respectively. The fish livers revealed total PCB and OCP levels ranging from 20 to 3200 ng/g ww and from 6.0 to 410 ng/g ww, respectively. Levels of both contaminant groups were significantly higher in samples from the Scheldt Estuary compared to the Belgian North Sea. For most species a highly inverse correlation was found between the concentration of contaminants and the distance to Antwerp (r between 0.812 and 0.901, p < 0.05), pointing to a higher degree of exposure further upstream. PCB and OCP exposures are highly correlated (r between 0.836 and 1.000, p < 0.05), which suggests that the pollution can be classified as historical. However, because urban and industrial centres may still be emitting these compounds, more recent point and non-point sources cannot be ruled out. Copyright 2004 Elsevier Ltd.

The legacy of organochlorine pesticide usage in a tropical semi-arid region (Jaguaribe River, Ceará, Brazil): Implications of the influence of sediment parameters on occurrence, distribution and fate.

PubMed

Oliveira, André H B; Cavalcante, Rivelino M; Duaví, Wersângela C; Fernandes, Gabrielle M; Nascimento, Ronaldo F; Queiroz, Maria E L R; Mendonça, Kamila V

2016-01-15

Between the 1940s and 1990s, immeasurable amounts of organochlorine pesticides (OCPs) were used in endemic disease control campaigns and agriculture in the tropical semi-arid regions of Brazil. The present study evaluated the legacy of banned OCP usage, considering the levels, ecological risk and dependence on sediment physicochemical properties for the fate and distribution in the Jaguaribe River. The sum concentration of OCPs (ΣOCPs) ranged from 5.09 to 154.43 ng·g(-1), comparable to the levels found in other tropical and subtropical regions that have traditionally used OCPs. The environmental and geographical distribution pattern of p,p-DDT, p,p-DDD and p,p-DDE shows that the estuarine zone contained more than 3.5 times the levels observed in the fluvial region, indicating that the estuary of the Jaguaribe River is a sink. The temporal pattern indicates application of dichloro-diphenyl-trichloroethanes (DDTs) in the past; however, there is evidence of recent input of these pesticides. High ecological risk was observed for levels of γ-hexachlorocyclohexanes (γ-HCH) and heptachlor, and moderate ecological risk was observed for levels of DDTs in sediments from the Jaguaribe River. The heptachlor, γ-HCH and hexachlorobenzene (HCB) concentrations depend on the organic and inorganic fractions of sediment from the Jaguaribe River, whereas the p,p-DDE, p,p-DDD, p,p-DDT and α-endosulfan concentrations depend solely on the organic fraction of the sediment.

Pesticides in the atmosphere: a comparison of gas-particle partitioning and particle size distribution of legacy and current-use pesticides

NASA Astrophysics Data System (ADS)

Degrendele, C.; Okonski, K.; Melymuk, L.; Landlová, L.; Kukučka, P.; Audy, O.; Kohoutek, J.; Čupr, P.; Klánová, J.

2016-02-01

This study presents a comparison of seasonal variation, gas-particle partitioning, and particle-phase size distribution of organochlorine pesticides (OCPs) and current-use pesticides (CUPs) in air. Two years (2012/2013) of weekly air samples were collected at a background site in the Czech Republic using a high-volume air sampler. To study the particle-phase size distribution, air samples were also collected at an urban and rural site in the area of Brno, Czech Republic, using a cascade impactor separating atmospheric particulates according to six size fractions. Major differences were found in the atmospheric distribution of OCPs and CUPs. The atmospheric concentrations of CUPs were driven by agricultural activities while secondary sources such as volatilization from surfaces governed the atmospheric concentrations of OCPs. Moreover, clear differences were observed in gas-particle partitioning; CUP partitioning was influenced by adsorption onto mineral surfaces while OCPs were mainly partitioning to aerosols through absorption. A predictive method for estimating the gas-particle partitioning has been derived and is proposed for polar and non-polar pesticides. Finally, while OCPs and the majority of CUPs were largely found on fine particles, four CUPs (carbendazim, isoproturon, prochloraz, and terbuthylazine) had higher concentrations on coarse particles ( > 3.0 µm), which may be related to the pesticide application technique. This finding is particularly important and should be further investigated given that large particles result in lower risks from inhalation (regardless the toxicity of the pesticide) and lower potential for long-range atmospheric transport.

The first countrywide monitoring of selected POPs: Polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and selected organochlorine pesticides (OCPs) in the atmosphere of Turkey

NASA Astrophysics Data System (ADS)

Kurt-Karakus, Perihan Binnur; Ugranli-Cicek, Tugba; Sofuoglu, Sait C.; Celik, Halil; Gungormus, Elif; Gedik, Kadir; Sofuoglu, Aysun; Okten, Hatice Eser; Birgul, Askın; Alegria, Henry; Jones, Kevin C.

2018-03-01

Atmospheric levels of 43 PCBs, 22 OCPs, and 14 PBDEs were determined in 16 cities at urban and rural sites by passive sampling to generate the first large-scale nationwide dataset of POP residues in Turkey's atmosphere. Sampling campaign was performed from May 2014 to April 2015 with three-month sampling periods at locations on east-west and north-south transects through the country to investigate seasonal and spatial variations, including long range atmospheric transport (LRAT). Factor analysis was conducted to infer on the potential sources. Overall average Σ43PCBs concentration was 108 ± 132 pg/m3. PCB-118 (26.3 ± 44.6 pg/m3) was the top congener, and penta-CBs had the highest contribution with 54.3%. ΣDDTs had the highest annual mean concentration with 134 ± 296 pg/m3 among the OCP groups among which the highest concentration compound was p'p-DDE (97.6 ± 236 pg/m3). Overall average concentration of Σ14PBDEs was 191 ± 329 pg/m3 with the highest contribution from BDE-190 (42%). Comparison of OCPs and PCBs concentrations detected at temperatures which were above and below annual average temperature indicated higher concentrations in the warmer periods, hence significance of secondary emissions for several OCPs and Σ43PCBs, as well as inference as LRAT from secondary emissions. The first nationwide POPs database constructed in this study, point to current use, local secondary emissions, and LRAT for different individual compounds, and indicate the need for regular monitoring.

Viscoelastic response of a model endothelial glycocalyx

NASA Astrophysics Data System (ADS)

Nijenhuis, Nadja; Mizuno, Daisuke; Spaan, Jos A. E.; Schmidt, Christoph F.

2009-06-01

Many cells cover themselves with a multifunctional polymer coat, the pericellular matrix (PCM), to mediate mechanical interactions with the environment. A particular PCM, the endothelial glycocalyx (EG), is formed by vascular endothelial cells at their luminal side, forming a mechanical interface between the flowing blood and the endothelial cell layer. The glycosaminoglycan (GAG) hyaluronan (HA) is involved in the main functions of the EG, mechanotransduction of fluid shear stress and molecular sieving. HA, due to its length, is the only GAG in the EG or any other PCM able to form an entangled network. The mechanical functions of the EG are, however, impaired when any one of its components is removed. We here used microrheology to measure the effect of the EG constituents heparan sulfate, chondroitin sulfate, whole blood plasma and albumin on the high-bandwidth mechanical properties of a HA solution. Furthermore, we probed the effect of the hyaldherin aggrecan, a constituent of the PCM of chondrocytes, and very similar to versican (present in the PCM of various cells, and possibly in the EG). We show that components directly interacting with HA (chondroitin sulfate and aggrecan) can increase the viscoelastic shear modulus of the polymer composite.

Combined oral contraceptives in polycystic ovary syndrome - indications and cautions.

PubMed

Bozdag, Gurkan; Yildiz, Bulent Okan

2013-01-01

Combined oral contraceptive pills (OCPs) have been used in women with polycystic ovary syndrome (PCOS) for the treatment of menstrual disorders, acne and hirsutism. Despite years of their use and broad clinical experience, there are still ongoing doubts concerning their implications for the cardiovascular system and carbohydrate metabolism both in the general population and women with PCOS. In the general population, the risk of venous thromboembolism is reported to be increased. However, arterial thrombotic events seem to require concomitant risk factors to appear during administration of OCPs. In terms of carbohydrate metabolism, available data do not consistently suggest an increased risk of impaired glucose tolerance (IGT) or conversion of IGT to type 2 diabetes mellitus, in spite of some subtle fluctuations in glucose and insulin levels. In subgroup analyses of epidemiological studies in the general population, there is no finding indicating an increased risk of cardiovascular disease and related mortality in premenopausal women with PCOS. There is no significant alteration in carbohydrate and lipid metabolism after use of OCP in PCOS either. The absence of further cardiometabolic risk with OCP use in PCOS might suggest some unproven preventive alterations in this patient population. Copyright © 2013 S. Karger AG, Basel.

Distribution of organic contamination of sediments from Ichkeul Lake and Bizerte Lagoon, Tunisia.

PubMed

Ben Salem, Fida; Ben Said, Olfa; Mahmoudi, Ezzeddine; Duran, Robert; Monperrus, Mathilde

2017-10-15

Analyses of organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and butyl tins (BuSn) were conducted on sediments from Ichkeul Lake-Bizerte Lagoon watershed (Tunisia). A total of 59 compounds (16 PAHs, 12 PCBs, 22 OCPs and 9 BuSn) were measured in 40 surface sediment samples collected during two campaigns. High concentrations of total PAHs were identified in the lagoon ranging from 122 to 19600ng·g -1 . Several OCPs, including endrin, dieldrin, and lindane (Hexachlorocyclohexane or HCH or BHC) were found in high concentrations in Ichkeul Lake, ranging from 28 to 2012ngg -1 . PAHs and OCPs varied seasonally, in response to the complex hydrology of the watershed. The concentrations of total PCBs ranged between 0.04 and 10.653ngg -1 and suggests low total PCBs sediment contamination, when compared to most international criteria. Total BuSn concentrations range between 67 and 526ng·g -1 , which are relatively low when compared to most international criteria and ecological risk assessments. This is the first study of organic contamination in Ichkeul Lake (RAMSAR and UNESCO World Heritage site). Copyright © 2017 Elsevier Ltd. All rights reserved.

Human health risk assessment and dietary intake of organochlorine pesticides through air, soil and food crops (wheat and rice) along two tributaries of river Chenab, Pakistan.

PubMed

Mahmood, Adeel; Malik, Riffat Naseem; Li, Jun; Zhang, Gan

2014-09-01

To assess the organochlorine pesticides (OCPs) contamination and their probable hazardous effects on human health; cereal crops (wheat and rice; n=28) agricultural soil (n=28) and air (n=6) samples were collected from Gujranwala division, Punjab Province, Pakistan. ∑OCPs concentration ranged between 123 and 635 pg m(-3), 31 and 365 ng g(-1) (dw), 2.72 and 36.6 ng g(-1) (dw), 0.55 and 15.2 ng g(-1) (dw) for air, soil, rice and wheat samples, respectively. DDTs were the predominant over other OCPSs detected from screened samples while the source apportionment analysis suggested the new inputs of DDTs in the study area. EDI (estimated daily intake) of ∑OCPs through rice and wheat was found 39 and 40 ng kg(-1) day(-1), respectively. Hazard ratios (HRs) on the basis 95th percentile concentrations were exceeding the integrity for most of the investigated OCP in rice and wheat. The results revealed that there is a severe risk to the human population of the study area through consumption of contaminated cereal crops. Copyright © 2014 Elsevier Ltd. All rights reserved.

Occurrence, composition and ecological restoration of organic pollutants in water environment of South Canal, China

NASA Astrophysics Data System (ADS)

Wang, Y. Z.; Lin, C.; Zhou, X. S.; Zhang, Y.; Han, C. G.

2017-08-01

Ecological restoration of polluted river water was carried out in South Canal by adding microbial water purifying agents and biological compound enzymes. The objective of present study was to investigate the ecological restoration effect of organic pollutants by this efficient immobilized microbial technologies, analysis the occurrence and composition of organic pollutants including fifteen persistent organochlorine pesticides (OCPs), seventeen polycyclic aromatic hydrocarbons (PAHs) and eighteen organophosphorus pesticides (OPPs) both in natural water environment and ecological restoration area of South Canal, China. Results showed that the total concentrations of OCPs ranged from 1.11 to 1.78 ng·L-1, PAHs from 52.76 to 60.28 ng·L-1, and OPPs from 6.51 to 17.50 ng·L-1. Microbial water purifying agents and biological compound enzymes essentially had no effects on biological degradation of OCPs and PAHs in the river, but could remove OPPs with degradation rates ranging from 19.6% to 62.8% (35.2% in average). Degradation mechanisms of microbial water purifying agents and biological compound enzymes on OCPs, PAHs and OPPs remained to be further studied. This technology has a certain value in practical ecological restoration of organic pollutants in rivers and lakes.

A pilot study on semivolatile organic compounds in senior care facilities: Implications for older adult exposures.

PubMed

Arnold, Karen; Teixeira, João Paulo; Mendes, Ana; Madureira, Joana; Costa, Solange; Salamova, Amina

2018-05-31

The occurrence of five groups of semivolatile organic compounds (SVOCs) (total of ∼120 distinct chemicals) was investigated in senior care facilities in the United States and in Portugal. Indoor settled dust samples were collected from fourteen facilities, and the concentrations of organophosphate esters (OPEs), brominated flame retardants (BFRs), polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), and polychlorinated biphenyls (PCBs) were measured in these samples. Overall, OPEs, PAHs, and BFRs were the most abundant, and OCPs and PCBs were the least abundant SVOC groups in dust collected from both U.S. and Portuguese facilities. ∑OPE, ∑PAH, and ∑BFR concentrations were significantly higher in U.S. facilities than those in Portuguese facilities (P < 0.001), while ∑OCP and ∑PCB concentrations were not different between the two countries (P < 0.05). The samples were collected from three different microenvironments, including bedrooms, living rooms, and corridors. ∑OPE, ∑PAH, and ∑BFR concentrations were up to five times higher in corridors compared to bedrooms and living rooms. ∑OCP and ∑PCB concentrations were overall higher in bedrooms and in living rooms and lower in corridors. Copyright © 2018 Elsevier Ltd. All rights reserved.

Dichlorodiphenyltrichloroethane (DDT), DDT Metabolites and Pregnancy Outcomes

PubMed Central

Kezios, Katrina L.; Liu, Xinhua; Cirillo, Piera M.; Cohn, Barbara A.; Kalantzi, Olga I.; Wang, Yunzhu; Petreas, Myrto X.; Park, June-Soo; Factor-Litvak, Pam

2012-01-01

Organochlorine pesticides (OCPs) are persistent endocrine disruptors. OCPs cross the placenta; this prenatal exposure has been associated with adverse pregnancy outcomes. We investigated associations between prenatal exposure to OCPs and gestational age and birth weight in 600 infants born between 1960 and 1963. The primary OCP was 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (p,p′-DDT), its primary metabolite, 1,1′-dichloro-2,2'-bis(p-chlorophenyl)ethylene(p,p′-DDE) and the contaminant, 1,1,1-trichloro-2-(p-chlorophenyl)-2-(o-chlorophenyl)-ethane (o,p′-DDT). Regression analysis indicated that for each natural log unit increase in p,p′-DDT, birth weight increased by 274 grams (95% CI 122, 425) when controlling for p,p′-DDE and o,p′-DDT. At a given level of p,p′-DDT exposure, o,p′-DDT and p,p′-DDE were associated with decreased birth weight. p,p′-DDE was negatively associated with length of gestation, controlling for p,p′-DDT and o,p′-DDT. These findings suggest opposing associations between exposure to p,p′-DDT and p,p′-DDE and birth weight. We did not find evidence to support mediation by maternal thyroid hormone status nor that the association differed by sex. PMID:23142753

The brown mussel Perna perna (L., 1758) as a sentinel species for chlorinated pesticide and dioxin-like compounds.

PubMed

Galvao, Petrus; Henkelmann, Bernhard; Longo, Renan; Torres, João Paulo Machado; Malm, Olaf; Schramm, Karl-Werner

2015-09-01

To contribute to the use of the tropical brown mussel Perna perna as a sentinel species for organochlorine pesticides (OCP) and polychlorinated biphenyls (PCB), the present study reports data on the toxicokinetics of these compounds in P. perna. Specifically, the authors present data on OCP and PCB bioaccumulation for eight sampling months from three bays (SE Brazil) and two transplant experiments (each 1 month long). Although seasonality is observed in the total lipid content of the whole soft tissue, with summer samples showing higher values, no such seasonality is observed in the OCP and PCB concentrations bioaccumulated by the mussel P. perna. Because no seasonal effect is observed in the annual OCP and PCB concentrations bioaccumulated by P. perna, the use of this species as a sentinel organism to monitor organochlorinated compounds is encouraged. One month of transplantation is not enough to allow the transplanted specimens to reach the concentrations observed in animals reared at the destination site. Nevertheless, P. perna showed a clear tendency to depurate the DDT metabolites p,p'-DDD and p,p'-DDE after 1 month of transplantation.

Montreal electronic artificial urinary sphincters: Our futuristic alternatives to the AMS800™.

PubMed

Biardeau, Xavier; Hached, Sami; Loutochin, Oleg; Campeau, Lysanne; Sawan, Mohamad; Corcos, Jacques

2017-10-01

We aimed to present three novel remotely controlled hydromechanical artificial urinary sphincters (AUSs) and report their in-vitro and ex-vivo results. We successively developed three distinct hydromechanical AUSs on the basis of the existing AMS800 ™ device by incorporating an electronic pump. No changes were made to the cuff and balloon. The AUS#1 was designed as an electromagnetically controlled device. The AUS#2 and AUS#3 were conceived as Bluetooth 2.1 remotely controlled and Bluetooth 4.0 remotely-controlled, adaptive devices, respectively. In-vitro experiments profiled occlusive cuff pressure (OCP) during a complete device cycle, with different predetermined OCP. Ex-vivo experiments were performed on a fresh pig bladder with 4 cm cuff placed around the urethra. Leak point pressure with different predetermined OCP values was successively measured during cystometry via a catheter at the bladder dome. Our in-vitro and ex-vivo experiments demonstrated that these three novel AUSs provided stable and predetermined OCP - within the physiological range - and completely deflated the cuff, when required, in a limited time compatible with physiological voiding cycles. Our three novel, remotely controlled AUSs showed promising results that should be confirmed by in-vivo experiments focusing on efficacy and safety.

Correlations between the in vitro and in vivo bioactivity of the Ti/HA composites fabricated by a powder metallurgy method.

PubMed

Ning, Congqin; Zhou, Yu

2008-11-01

Ti/HA composites were successfully prepared by a powder metallurgy method and the effect of phase composition on the in vitro and in vivo bioactivity of the Ti/HA composites was investigated in the present study. The correlations between the in vitro and in vivo biological behaviors were highlighted. The results showed that the in vitro and in vivo bioactivity of the Ti/HA composites was dependent on their phase composition. The in vitro bioactivity of the Ti/HA composites was evaluated in simulated body fluid with ion concentrations similar to those of human plasma. After immersion in the simulated body fluid for a certain time, apatite precipitations formed on the surface of the composites with an initial titanium content of 50 and 70 wt.%, and no apatite was found on the surface of the composite with 30% titanium. Ti(2)O was responsible for the apatite formation on the surfaces of the composites. For in vivo analysis, Ti/HA cylinders were implanted in the metaphases of the rabbit femur. At the early stage of implantation, the new bone formed on the surface of the composite with 30% titanium was much less than that on the surfaces of the composites with 50% and 70% titanium. All the Ti/HA composites formed a chemical bone-bonding interface with the host bone by 6 months after implantation. The Ti/HA composites formed the bone-bonding interface with the surrounding bone through an apatite layer. The results in the present study suggested that the in vivo results agreed well with the in vitro results.

Non-linear processing of a linear speech stream: The influence of morphological structure on the recognition of spoken Arabic words.

PubMed

Gwilliams, L; Marantz, A

2015-08-01

Although the significance of morphological structure is established in visual word processing, its role in auditory processing remains unclear. Using magnetoencephalography we probe the significance of the root morpheme for spoken Arabic words with two experimental manipulations. First we compare a model of auditory processing that calculates probable lexical outcomes based on whole-word competitors, versus a model that only considers the root as relevant to lexical identification. Second, we assess violations to the root-specific Obligatory Contour Principle (OCP), which disallows root-initial consonant gemination. Our results show root prediction to significantly correlate with neural activity in superior temporal regions, independent of predictions based on whole-word competitors. Furthermore, words that violated the OCP constraint were significantly easier to dismiss as valid words than probability-matched counterparts. The findings suggest that lexical auditory processing is dependent upon morphological structure, and that the root forms a principal unit through which spoken words are recognised. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Structure-guided development of a high-affinity human Programmed Cell Death-1: Implications for tumor immunotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lázár-Molnár, Eszter; Scandiuzzi, Lisa; Basu, Indranil

Programmed Cell Death-1 (PD-1) is an inhibitory immune receptor, which plays critical roles in T cell co-inhibition and exhaustion upon binding to its ligands PD-L1 and PD-L2. We report the crystal structure of the human PD-1 ectodomain and the mapping of the PD-1 binding interface. Mutagenesis studies confirmed the crystallographic interface, and resulted in mutant PD-1 receptors with altered affinity and ligand-specificity. In particular, a high-affinity mutant PD-1 (HA PD-1) exhibited 45 and 30-fold increase in binding to PD-L1 and PD-L2, respectively, due to slower dissociation rates. This mutant (A132L) was used to engineer a soluble chimeric Ig fusion proteinmore » for cell-based and in vivo studies. HA PD-1 Ig showed enhanced binding to human dendritic cells, and increased T cell proliferation and cytokine production in a mixed lymphocyte reaction (MLR) assay. Moreover, in an experimental model of murine Lewis lung carcinoma, HA PD-1 Ig treatment synergized with radiation therapy to decrease local and metastatic tumor burden, as well as in the establishment of immunological memory responses. Our studies highlight the value of structural considerations in guiding the design of a high-affinity chimeric PD-1 Ig fusion protein with robust immune modulatory properties, and underscore the power of combination therapies to selectively manipulate the PD-1 pathway for tumor immunotherapy.« less

NAS (HOST/ARTS IIIA) to VME Modem Interface ATC Interface Hardware Manual

DTIC Science & Technology

1990-10-01

SIXT,RXSYNC,RXACTIVE,ALLOWI) IO,C,0,1,O,O1 - > [^bf,1,1,O,0J;vector 104 [o,c,0,1,o,0J -> [^hf,1,1,O,OJ;vector [I,C,0,1,O,0] -> [Abf,1,1,0,OJ;vector IO,C...VFU.T(R 501 C’-35 Io,c,1,1,o,o,o1 -> rhb ,0,01;i [X,C,1,1,0,O,1] -> ["hf,0,0; [1,C,1,I,0,1,01 -> [^ha,0,1];LACT (MTE)-S2 io,C,,1,0,1,01 -> I^ha,0,1; [1

The crystal structure of a cyanobacterial water-soluble carotenoid binding protein.

PubMed

Kerfeld, Cheryl A; Sawaya, Michael R; Brahmandam, Vishnu; Cascio, Duilio; Ho, Kwok Ki; Trevithick-Sutton, Colleen C; Krogmann, David W; Yeates, Todd O

2003-01-01

Carotenoids undergo a wide range of photochemical reactions in animal, plant, and microbial systems. In photosynthetic organisms, in addition to light harvesting, they perform an essential role in protecting against light-induced damage by quenching singlet oxygen, superoxide anion radicals, or triplet-state chlorophyll. We have determined the crystal structure of a water-soluble orange carotenoid protein (OCP) isolated from the cyanobacterium Arthrospira maxima at a resolution of 2.1 A. OCP forms a homodimer with one carotenoid molecule per monomer. The carotenoid binding site is lined by a striking number of methionine residues. The structure reveals several possible ways in which the protein environment influences the spectral properties of the pigment and provides insight into how the OCP carries out its putative functions in photoprotection.

Effect of Mg2+ on acidic calcium phosphate phases grown by electrodeposition

NASA Astrophysics Data System (ADS)

Correia, Matheus Bento; Júnior, José Pedro Gualberto; Macedo, Michelle Cardinale S. S.; Resende, Cristiane Xavier; dos Santos, Euler Araujo

2017-10-01

In this work, the effect of Mg2+ ions on the electrodeposition of dicalcium phosphate dihydrate (DCPD), octacalcium phosphate (OCP) and calcium-deficient hydroxyapatite (CDHA) crystals on a commercially pure titanium (cp-Ti) substrate was evaluated. We demonstrated that Mg2+ ions could change the morphology of the coatings by inhibiting the growth rate of the OCP and CDHA crystals and diminishing the crystallite size of DCPD. The inhibition effect on OCP and CDHA was most likely due to a surface adsorption mechanism since no evidence of a doping process was observed using Rietveld refinement and electron diffraction analyses. Conversely, the presence of Mg2+ ions generated a favorable condition for the nucleation of a new Mg2+-rich DCPD crystal population, presenting smaller crystallite sizes.

The influence of hyaluronan on the structure of a DPPC-bilayer under high pressures.

PubMed

Zander, Thomas; Wieland, D C Florian; Raj, Akanksha; Wang, Min; Nowak, Benedikt; Krywka, Christina; Dėdinaitė, Andra; Claesson, Per Martin; Garamus, Vasil M; Schreyer, Andreas; Willumeit-Römer, Regine

2016-06-01

The superior lubrication properties of synovial joints have inspired many studies aiming at uncovering the molecular mechanisms which give rise to low friction and wear. However, the mechanisms are not fully understood yet, and, in particular, it has not been elucidated how the biolubricants present at the interface of cartilage respond to high pressures, which arise during high loads of joints. In this study we utilize a simple model system composed of two biomolecules that have been implied as being important for joint lubrication. It consists of a solid supported dipalmitoylphosphatidylcholin (DPPC) bilayer, which was formed via vesicles fusion on a flat Si wafer, and the anionic polysaccharide hyaluronan (HA). We first characterized the structure of the HA layer that adsorbed to the DPPC bilayers at ambient pressure and different temperatures using X-ray reflectivity (XRR) measurements. Next, XRR was utilized to evaluate the response of the system to high hydrostatic pressures, up to 2kbar (200MPa), at three different temperatures. By means of fluorescence microscopy images the distribution of DPPC and HA on the surface was visualized. Our data suggest that HA adsorbs to the headgroup region that is oriented towards the water side of the supported bilayer. Phase transitions of the bilayer in response to temperature and pressure changes were also observed in presence and absence of HA. Our results reveal a higher stability against high hydrostatic pressures for DPPC/HA composite layers compared to that of the DPPC bilayer in absence of HA. Copyright © 2016 Elsevier B.V. All rights reserved.

Boron nitride nanotube reinforced hydroxyapatite composite: mechanical and tribological performance and in-vitro biocompatibility to osteoblasts.

PubMed

Lahiri, Debrupa; Singh, Virendra; Benaduce, Ana Paula; Seal, Sudipta; Kos, Lidia; Agarwal, Arvind

2011-01-01

This study proposes boron nitride nanotube (BNNT) reinforced hydroxyapatite (HA) as a novel composite material for orthopedic implant applications. The spark plasma sintered (SPS) composite structure shows higher density compared to HA. Minimal lattice mismatch between HA and BNNT leads to coherent bonding and strong interface. HA-4 wt% BNNT composite offers excellent mechanical properties-120% increment in elastic modulus, 129% higher hardness and 86% more fracture toughness, as compared to HA. Improvements in the hardness and fracture toughness are related to grain refinement and crack bridging by BNNTs. HA-BNNT composite also shows 75% improvement in the wear resistance. The wear morphology suggests localized plastic deformation supported by the sliding of outer walls of BNNT. Osteoblast proliferation and cell viability show no adverse effect of BNNT addition. HA-BNNT composite is, thus, envisioned as a potential material for stronger orthopedic implants. Copyright © 2010 Elsevier Ltd. All rights reserved.

Fortifying the Bone-Implant Interface Part 2: An In Vivo Evaluation of 3D-Printed and TPS-Coated Triangular Implants

PubMed Central

Lindsey, Derek P.; Woods, Shane A.; Lalor, Peggy A.; Gundanna, Mukund I.; Yerby, Scott A.

2017-01-01

Background Minimally invasive surgical fusion of the sacroiliac (SI) joint using machined solid triangular titanium plasma spray (TPS) coated implants has demonstrated positive clinical outcomes in SI joint pain patients. Additive manufactured (AM), i.e. 3D-printed, fenestrated triangular titanium implants with porous surfaces and bioactive agents, such as nanocrystalline hydroxyapatite (HA) or autograft, may further optimize bony fixation and subsequent biomechanical stability. Methods A bilateral ovine distal femoral defect model was used to evaluate the cancellous bone-implant interfaces of TPS-coated and AM implants. Four implant groups (n=6/group/time-point) were included: 1)TPS-coated, 2)AM, 3)AM+HA, and 4)AM+Autograft. The bone-implant interfaces of 6- and 12-week specimens were investigated via radiographic, biomechanical, and histomorphometric methods. Results Imaging showed peri-implant bone formation around all implants. Push-out testing demonstrated forces greater than 2500 N, with no significant differences among groups. While TPS implants failed primarily at the bone-implant interface, AM groups failed within bone ~2-3mm away from implant surfaces. All implants exhibited bone ongrowth, with no significant differences among groups. AM implants had significantly more bone ingrowth into their porous surfaces than TPS-coated implants (p<0.0001). Of the three AM groups, AM+Auto implants had the greatest bone ingrowth into the porous surface and through their core (p<0.002). Conclusions Both TPS and AM implants exhibited substantial bone ongrowth and ingrowth, with additional bone through growth into the AM implants’ core. Overall, AM implants experienced significantly more bone infiltration compared to TPS implants. While HA-coating did not further enhance results, the addition of autograft fostered greater osteointegration for AM implants. Clinical Relevance Additive manufactured implants with a porous surface provide a highly interconnected porous surface that has comparatively greater surface area for bony integration. Results suggest this may prove advantageous toward promoting enhanced biomechanical stability compared to TPS-coated implants for SI joint fusion procedures. PMID:28765800

Cycle scheduling for in vitro fertilization with oral contraceptive pills versus oral estradiol valerate: a randomized, controlled trial

PubMed Central

2013-01-01

Background Both oral contraceptive pills (OCPs) and estradiol (E2) valerate have been used to schedule gonadotropin-releasing hormone (GnRH) antagonist in vitro fertilization (IVF) cycles and, consequently, laboratory activities. However, there are no studies comparing treatment outcomes directly between these two pretreatment methods. This randomized controlled trial was aimed at finding differences in ongoing pregnancy rates between GnRH antagonist IVF cycles scheduled with OCPs or E2 valerate. Methods Between January and May 2012, one hundred consecutive patients (nonobese, regularly cycling women 18–38 years with normal day 3 hormone levels and <3 previous IVF/ICSI attempts) undergoing IVF with the GnRH antagonist protocol were randomized to either the OCP or E2 pretreatment arms, with no restrictions such as blocking or stratification. Authors involved in data collection and analysis were blinded to group assignment. Fifty patients received OCP (30 μg ethinyl E2/150 μg levonorgestrel) for 12–16 days from day 1 or 2, and stimulation was started 5 days after stopping OCP. Similarly, 50 patients received 4 mg/day oral E2 valerate from day 20 for 5–12 days, until the day before starting stimulation. Results Pretreatment with OCP (mean±SD, 14.5±1.7 days) was significantly longer than with E2 (7.8±1.9 days). Stimulation and embryological characteristics were similar. Ongoing pregnancy rates (46.0% vs. 44.0%; risk difference, –2.0% [95% CI –21.2% to 17.3%]), as well as implantation (43.5% vs. 47.4%), clinical pregnancy (50.0% vs. 48.0%), clinical miscarriage (7.1% vs. 7.7%), and live birth (42.0% vs. 40.0%) rates were comparable between groups. Conclusions This is the first study to directly compare these two methods of cycle scheduling in GnRH antagonist cycles. Our results fail to show statistically significant differences in ongoing pregnancy rates between pretreatment with OCP and E2 for IVF with the GnRH antagonist protocol. Although the study is limited by its sample size, our results may contribute to a future meta-analysis. An interesting future direction would be to extend our study to women with decreased ovarian reserve, as these are the patients in whom an increase in oocyte yield—due to the hypothetical beneficial effect of steroid pretreatment on follicular synchronization—could more easily be demonstrated. Trial registration ClinicalTrials.gov http://NCT01501448. PMID:24074027

Reduced Order Modeling for Rapid Simulations of Blast and Rollover Events of a Ground Vehicle and its Occupants Using Rigid Body Dynamic Models

DTIC Science & Technology

2013-03-11

information is available. A 4-point harness system including lap and shoulder beltsand center buckle was positioned on the dummy, as shown in Figure 3.1... Lamb , STE/Analytics, US Army TARDEC  Dr. Tom McGrath, US Navy NSWC-IHD  Mr. Kirk Miller, OCP-TECD Standards and Specifications, TARDEC/GSS  Mr

Comparison of Norethindrone-Containing OCPs to Desogestrel OCPs and Depro-Provera in Women

DTIC Science & Technology

2001-10-01

servicewomen requesting contraception have been prescribed a monophasic norethindrone-containing birth control pill (NOCA). In 1992, injectable depot...medroxyprogesterone acetate (DMPA) received approval and more recently, birth control pills using the new progestin, desogestrel (DOCA), have been made...an injectable progestational agent that offers a highly effective, safe, convenient, reversible and almost user-independent method of birth control (12

Telomere length is short in PCOS and oral contraceptive does not affect the telomerase activity in granulosa cells of patients with PCOS.

PubMed

Li, Ying; Deng, Bingbing; Ouyang, Nengyong; Yuan, Ping; Zheng, Lingyan; Wang, Wenjun

2017-07-01

Our study aimed to investigate the association of telomerase activity (TA) and telomere length (TL) in granulosa cells (GCs) with IVF outcomes of polycystic ovary syndrome (PCOS) patients, and the effects of oral contraceptive pill (OCP) pretreatment on these two parameters. One hundred sixty-three infertile women were enrolled and divided into a PCOS group (n = 65) and a non-PCOS group (n = 98). The PCOS group was further divided into an OCP pretreatment group (n = 35) and a non-OCP pretreatment group (n = 30), a TA <0.070 group (n = 34) and a TA ≥0.070 group (n = 31), and a TL <1 group (n = 41) and a TL ≥1 group (n = 24), respectively. No obvious differences were observed in TA between these groups. The TL was 0.971 in PCOS group and 1.118 in non-PCOS group (P = 0.005). The patients with TL ≥1 accounted for 36.9% in PCOS group and 54.1% in non-PCOS group (P = 0.032). The average duration of infertility for PCOS patients was 5 years in TA <0.070 group and 4 years in TA ≥0.070 group (P = 0.038), and 5 years in TL <1 group and 3 years in TL ≥1 group (P = 0.006), respectively. No obvious differences were observed in IVF outcomes between these groups. No obvious differences were observed in TA, TL, or IVF outcomes between OCP pretreatment group and non-OCP pretreatment group in PCOS patients. Shorter TL was found in PCOS patients. The TA levels did not change significantly in PCOS patients. PCOS patients with a lower TA level and shorter telomeres had an earlier onset of infertility symptoms. No predictive value was found for TA and TL in terms of embryo quality or IVF outcomes in PCOS patients, and no effect OCP pretreatment was observed on either TA and TL.

Association between Organochlorine Pesticide Levels in Breast Milk and Their Effects on Female Reproduction in a Taiwanese Population

PubMed Central

Chen, Men-Wen; Que, Danielle E.; Gou, Yan-You; Tayo, Lemmuel L.; Hsu, Yi-Chyun; Chen, Young-Bin; Chen, Fu-An; Chao, How-Ran

2018-01-01

Only few studies have focused on organochlorine pesticides (OCPs) in breast milk and the related health risks for women in Taiwan. Our goal is to examine breast milk OCPs and their associations with female reproductive function (infertility, gynecological diseases, and menstruation characteristics) as well as their correlation with sociodemographic parameters (age, pre-pregnant body mass index (BMI), annual incomes, population, birth year, and parity) and dietary habit. The breast milk samples were collected in southern Taiwan (n = 68) from 2013 to 2016 and the OCP residues were analyzed using high resolution gas chromatography with low resolution mass spectrometry (HRGC/LRMS). The results show that the most abundant OCP residues in the breast milk was ΣDDT with the geometric mean ± standard deviation of 9.81 ± 7.52 ng−1 lipid−1 followed by ΣHCH (0.539 ± 0.557 ng−1·lipid−1). In the principal component analysis, cis-chlordane (cis-CHL) and γ-HCH were found to be related to participants who received medical treatment for infertility, and 4,4′-DDT was associated with those who received gynecological surgery. The logistic regression showed that the odds ratio (OR) of log γ-hexachlorocyclohexane (γ-HCH) was higher for mothers who had received medical treatment for infertility than for the normal group (OR = 25.6, p = 0.035) after adjustments for age, pre-pregnant BMI, annual income, population (i.e., native-born Taiwanese), birth year, and parity. Cow milk and beef consumption as well as menstruation characteristics such as average menstrual period (>5 days), shortest menstrual period (<3 days), and women who had taken hormonal drugs were significantly associated to several OCP residues in the breast milk. In addition, ΣHCH including β-HCH and γ-HCH was correlated with annual family income and gravidity as well as cow milk and beef consumptions. Overall, γ-HCH exhibited a probable association with the infertility diseases of Taiwanese women, and dietary habit might play an important role in the female Taiwanese exposure to OCPs. PMID:29735922

A Structural Model of a P450-Ferredoxin Complex from Orientation-Selective Double Electron-Electron Resonance Spectroscopy.

PubMed

Bowen, Alice M; Johnson, Eachan O D; Mercuri, Francesco; Hoskins, Nicola J; Qiao, Ruihong; McCullagh, James S O; Lovett, Janet E; Bell, Stephen G; Zhou, Weihong; Timmel, Christiane R; Wong, Luet Lok; Harmer, Jeffrey R

2018-02-21

Cytochrome P450 (CYP) monooxygenases catalyze the oxidation of chemically inert carbon-hydrogen bonds in diverse endogenous and exogenous organic compounds by atmospheric oxygen. This C-H bond oxy-functionalization activity has huge potential in biotechnological applications. Class I CYPs receive the two electrons required for oxygen activation from NAD(P)H via a ferredoxin reductase and ferredoxin. The interaction of Class I CYPs with their cognate ferredoxin is specific. In order to reconstitute the activity of diverse CYPs, structural characterization of CYP-ferredoxin complexes is necessary, but little structural information is available. Here we report a structural model of such a complex (CYP199A2-HaPux) in frozen solution derived from distance and orientation restraints gathered by the EPR technique of orientation-selective double electron-electron resonance (os-DEER). The long-lived oscillations in the os-DEER spectra were well modeled by a single orientation of the CYP199A2-HaPux complex. The structure is different from the two known Class I CYP-Fdx structures: CYP11A1-Adx and CYP101A1-Pdx. At the protein interface, HaPux residues in the [Fe 2 S 2 ] cluster-binding loop and the α3 helix and the C-terminus residue interact with CYP199A2 residues in the proximal loop and the C helix. These residue contacts are consistent with biochemical data on CYP199A2-ferredoxin binding and electron transfer. Electron-tunneling calculations indicate an efficient electron-transfer pathway from the [Fe 2 S 2 ] cluster to the heme. This new structural model of a CYP-Fdx complex provides the basis for tailoring CYP enzymes for which the cognate ferredoxin is not known, to accept electrons from HaPux and display monooxygenase activity.

Oral contraceptives modify the effect of GATA3 polymorphisms on the risk of asthma at the age of 18 years via DNA methylation.

PubMed

Guthikonda, Kranthi; Zhang, Hongmei; Nolan, Vikki G; Soto-Ramírez, Nelís; Ziyab, Ali H; Ewart, Susan; Arshad, Hasan S; Patil, Veeresh; Holloway, John W; Lockett, Gabrielle A; Karmaus, Wilfried

2014-01-01

The prevalence of asthma in girls increases after puberty. Previous studies have detected associations between sex hormones and asthma, as well as between sex hormones and T helper 2 (Th2) asthma-typical immune responses. Therefore, we hypothesized that exogenous or endogenous sex hormone exposure (represented by oral contraceptive pill (OCP) use and early menarche, respectively) are associated with DNA methylation (DNA-M) of the Th2 transcription factor gene, GATA3, in turn affecting the risk of asthma in girls, possibly in interaction with genetic variants. Blood samples were collected from 245 female participants aged 18 years randomly selected for methylation analysis from the Isle of Wight birth cohort, UK. Information on use of OCPs, age at menarche, and concurrent asthma were assessed by questionnaire. Genome-wide DNA-M was determined using the Illumina Infinium HumanMethylation450 beadchip. In a first stage, we tested the interaction between sex hormone exposure and genetic variants on DNA-M of specific cytosine-phosphate-guanine (CpG) sites. In a second stage, we determined whether these CpG sites interact with genetic variants in GATA3 to explain the risk of asthma. Interactions between OCP use and seven single nucleotide polymorphisms (SNPs) of GATA3 were analyzed for 14 CpG sites (stage 1). The interaction between OCP use and SNP rs1269486 was found to be associated with the methylation level of cg17124583 (P = 0.002, false discovery rate (FDR) adjusted P = 0.04). DNA-M of this same CpG site was also influenced by the interaction between age at menarche and rs1269486 (P = 0.0017). In stage 2, we found that cg17124583 modified the association of SNP rs422628 with asthma risk at the age of 18 years (P = 0.006, FDR adjusted P = 0.04). Subjects with genotype AG showed an increase in average risk ratio (RR) from 0.31 (95% CI: 0.10 to 0.8) to 11.65 (95% CI: 1.71 to 79.5) when methylation level increased from 0.02 to 0.12, relative to genotype AA. A two-stage model consisting of genetic variants in the GATA3 gene, OCP use, age at menarche, and DNA-M may explain how sex hormones in women can increase the asthma prevalence after puberty.

Humic acid transport in saturated porous media: influence of flow velocity and influent concentration.

PubMed

Wei, Xiaorong; Shao, Mingan; Du, Lina; Horton, Robert

2014-12-01

Understanding the transport of humic acids (HAs) in porous media can provide important and practical evidence needed for accurate prediction of organic/inorganic contaminant transport in different environmental media and interfaces. A series of column transport experiments was conducted to evaluate the transport of HA in different porous media at different flow velocities and influent HA concentrations. Low flow velocity and influent concentration were found to favor the adsorption and deposition of HA onto sand grains packed into columns and to give higher equilibrium distribution coefficients and deposition rate coefficients, which resulted in an increased fraction of HA being retained in columns. Consequently, retardation factors were increased and the transport of HA through the columns was delayed. These results suggest that the transport of HA in porous media is primarily controlled by the attachment of HA to the solid matrix. Accordingly, this attachment should be considered in studies of HA behavior in porous media. Copyright © 2014. Published by Elsevier B.V.

Fabrication and characterization of plasma-sprayed HA/SiO(2) coatings for biomedical application.

PubMed

Morks, M F

2008-01-01

Fused silica powder has been mixed with hydroxyapatite (HA) powder and plasma sprayed by using gas tunnel-type plasma jet. The influence of silica content (10 wt% and 20 wt%) on the microstructure and mechanical properties of HA-silica coatings was investigated. For investigating the microstructure and mechanical properties of HA-silica coatings, SUS 304 stainless steel was used as substrate material. The spraying was carried out on roughened substrate in an atmospheric chamber. Scanning electron microscope micrographs of cross-sectioned HA/SiO(2) coatings showed that the sprayed HA coatings with 10 and 20 wt% SiO(2) have dense structure with low porosity compared to the pure HA coatings. On the other hand, as the amount of silica was increased the coatings became denser, harder and exhibited high abrasive wear resistance. The presence of silica significantly improved the adhesive strength of HA/SiO(2) coatings mainly due to the increase in bonding strength of the coating at the interface.

In vitro cytotoxicity and in vivo osseointergration properties of compression-molded HDPE-HA-Al2O3 hybrid biocomposites.

PubMed

Tripathi, Garima; Gough, Julie E; Dinda, Amit; Basu, Bikramjit

2013-06-01

The aim of this study was to investigate the in vivo biocompatibility in terms of healing of long segmental bone defect in rabbit model as well as in vitro cytotoxicity of eluates of compression-molded High density polyethylene (HDPE)-hydroxyapatite (HA)-aluminum oxide (Al2O3) composite-based implant material. Based on the physical property in terms of modulus and strength properties, as reported in our recent publication, HDPE-40 wt % HA and HDPE-20 wt % HA-20 wt % Al2O3 hybrid composites were used for biocompatibility assessment. Osteoblasts cells were cultured in conditioned media, which contains varying amount of composite eluate (0.01, 0.1, and 1.0 wt %). In vitro, the eluates did not exhibit any significant negative impact on proliferation, mineralization or on morphology of human osteoblast cells. In vivo, the histological assessment revealed neobone formation at the bone/implant interface, characterized by the presence of osteoid and osteoblasts. The observation of osteoclastic activity indicates the process of bone remodeling. No inflammation to any noticeable extent was observed at the implantation site. Overall, the combination of in vitro and in vivo results are suggestive of potential biomedical application of compression-molded HDPE- 20 wt % HA- 20 wt % Al2O3 composites to heal long segmental bone defects without causing any toxicity of bone cells. Copyright © 2012 Wiley Periodicals, Inc.

Universality in the Equilibration of Quenched Yukawa One Component Plasmas

NASA Astrophysics Data System (ADS)

Langin, Thomas; McQuillen, Patrick; Strickler, Trevor; Maksimovic, Nikola; Pohl, Thomas; Killian, Thomas

2015-11-01

We study the equilibration of a Yukawa One Component Plasma (OCP) after a rapid change in the screening parameter from κ0 = ∞ to κf (n ,Te) , which is realized by photoionizing a laser cooled (T ~ 10 mK), uncorrelated gas of 88Sr atoms with density n between 1014 m-3 and 3 ×1016 m-3 using a two photon process in which the energy of one of the photons is adjustable. The excess photon energy above the ionization threshold sets the electron temperature, Te, and thus gives us control of κf. The resultant plasma is a classical plasma with strongly coupled ions, and is therefore described by the Yukawa OCP model with the electrons treated as a screening background. After photoionization, the ions develop spatial correlations to minimize their interaction energy, thus heating the ions. Since the dynamics of a Yukawa OCP depend solely on κ, we expect the heating process to be uniquely determined by κf. We verify this behavior by measuring the ion heating curve and comparing it to molecular dynamics simulations. We also report on how this behavior can be used to accurately measure n given a measured equilibration curve at a known Te. This work was supported by the United States National Science Foundation and the Department of Energy (PHY-0714603), the Air Force Office of Scientific Research (FA9550- 12-1-0267), and the Department of Defense (DoD) through the NDSEG Program.

Organochlorine pesticides and thiamine in eggs of largemouth bass and American alligators and their relationship with early life-stage mortality

USGS Publications Warehouse

Sepulveda, M.S.; Wiebe, J.J.; Honeyfield, D.C.; Rauschenberger, H.R.; Hinterkopf, J.P.; Johnson, W.E.; Gross, T.S.

2004-01-01

Thiamine deficiency has been linked to early mortality syndrome in salmonids in the Great Lakes. This study was conducted to compare thiamine concentrations in American alligators (Alligator mississippiensis) and Florida largemouth bass (Micropterus salmoides floridanus) eggs from sites with high embryo mortality and high exposure to organochlorine pesticides (OCPs) (Lakes Apopka and Griffin, and Emeralda Marsh, Florida, USA) to those from sites that have historically exhibited low embryo mortality and low OCPs (Lakes Woodruff and Orange, Florida). During June-July 2000, 20 alligator clutches were collected from these sites, artificially incubated, and monitored for embryo mortality. Thiamine and OCPs were measured in one egg/clutch. During February 2002, 10 adult female bass were collected from Emeralda Marsh and Lake Woodruff and mature ovaries analyzed for thiamine and OCP concentrations. Although ovaries from the Emeralda Marsh bass contained almost 1,000-fold more OCPs compared with the reference site, Lake Woodruff, there were no differences in thiamine concentrations between sites (11,710 vs. 11,857 pmol/g). In contrast, alligator eggs from the reference site had five times the amount of thiamine compared with the contaminated sites (3,123 vs. 617 pmol/g). Similarly, clutches with > 55% hatch rates had significantly higher concentrations of thiamine compared with clutches with <54% hatch rates (1,119 vs. 201 pmol/g). These results suggest that thiamine deficiency might be playing an important role in alligator embryo survival but not in reproductive failure and recruitment of largemouth bass. The cause(s) of this thiamine deficiency are unknown but might be related to differences in the nutritional value of prey items across the sites studied and/or to the presence of high concentration of contaminants in eggs. ?? Wildlife Disease Association 2004.

Biofuel cell based self-powered sensing platform for L-cysteine detection.

PubMed

Hou, Chuantao; Fan, Shuqin; Lang, Qiaolin; Liu, Aihua

2015-03-17

L-cysteine (L-Cys) detection is of great importance because of its crucial roles in physiological and clinical diagnoses. In this study, a glucose/O2 biofuel cell (BFC) was assembled by using flavin adenine dinucleotide-dependent glucose dehydrogenase (FAD-GDH)-based bioanode and laccase-based biocathode. Interestingly, the open circuit potential (OCP) of the BFC could be inhibited by Cu(2+) and subsequently activated by L-Cys, by which a BFC-based self-powered sensing platform for the detection of L-Cys was proposed. The FAD-GDH activity can be inhibited by Cu(2+) and, in turn, subsequent reversible activation by L-Cys because of the binding preference of L-Cys toward Cu(2+) by forming the Cu-S bond. The preferential interaction between L-Cys and Cu(2+) facilitated Cu(2+) to remove from the surface of the bioanode, and thus, the OCP of the system could be turned on. Under optimized conditions, the OCP of the BFC was systematically increased upon the addition of the L-Cys. The OCP increment (ΔOCP) was linear with the concentration of L-Cys within 20 nM to 3 μM. The proposed sensor exhibited lower detection limit of 10 nM L-Cys (S/N = 3), which is significantly lower than those values for other methods reported so far. Other amino acids and glutathione did not affect L-Cys detection. Therefore, this developed approach is sensitive, facile, cost-effective, and environmental-friendly, and could be very promising for the reliable clinically detecting of L-Cys. This work would trigger the interest of developing BFCs based self-powered sensors for practical applications.

Hirsutism in Polycystic Ovary Syndrome: Pathophysiology and Management.

PubMed

Spritzer, Poli Mara; Barone, Carolina Rocha; Oliveira, Fabiana Bazanella de

2016-01-01

Hirsutism is defined as the presence of terminal hair with male distribution in women, and polycystic ovary syndrome (PCOS) is the most common etiology of hirsutism. The aim of this study is to review aspects of hair growth that are relevant for the understanding of hirsutism in PCOS, along with current treatment alternatives. The prevalence of hirsutism in PCOS ranges from 70 to 80%, vs. 4% to 11% in women in the general population. Hirsutism in PCOS is associated with both ovarianderived androgen excess and individual sensitivity of the pilosebaceous unit to androgens. Interventions to decrease hirsutism in PCOS include the suppression of androgen excess by combined oral contraceptives (OCPs). If OCPs are contraindicated, mainly in the presence of insulin-resistance related comorbidities, a second-line option for reducing androgen secretion may be metformin associated with lifestyle changes. Other interventions should be guided by hirsutism severity, determined by the modified Ferriman-Gallwey score, and by the amount of distress hirsutism causes to the patient, and should be maintained for at least 6-12 months. Mild hirsutism is usually treated with a combination of non-pharmacological methods and OCPs, whereas moderate and severe hirsutism may require a combination of antiandrogens and OCPs, or, if OCPs cannot be used, antiandrogens plus a safe contraceptive method. In all cases, strong clinical support is crucial to ensure treatment adherence and success. The understanding of the pathophysiology of hirsutism in PCOS, as well as classifying its severity and the distress it causes to each patient is essential to choose the proper treatment. The presence of metabolic comorbidities and menstrual disturbances will also guide the individualized management of hirsutism in women with PCOS.

A Qualitative Study of Prescription Contraception Use: The Perspectives of Users, General Practitioners and Pharmacists.

PubMed

Sweeney, Leigh-Ann; Molloy, Gerard J; Byrne, Molly; Murphy, Andrew W; Morgan, Karen; Hughes, Carmel M; Ingham, Roger

2015-01-01

The oral contraceptive pill (OCP) remains the most popular form of prescription contraception in many countries, despite adherence difficulties for many. Uptake of long acting reversible contraceptives (LARCs), which are less reliant on user adherence, remains low. The aim of this study was to explore the experiences of, and attitudes towards, prescription contraception amongst samples of contraception users, general practitioners (GPs) and pharmacists. We conducted a qualitative study using semi-structured interviews with 18 contraception users, 18 GPs and 9 pharmacists. The study took place in Galway, Republic of Ireland between June and September 2014. Thematic analysis was used to analyse the data. Overall, contraception users were more familiar with the OCP, and all the women interviewed began their prescription contraception journey using this method. All participants identified episodes of poor adherence throughout the reproductive life course. The identified barriers for use of LARCs were lack of information, misconceptions, lack of access and high cost. In contrast, GPs believed that adherence to the OCP was good and stated they were more likely to prescribe the OCP than other methods, as they were most familiar with this option. Barriers to prescribing LARCSs were time, cost to practice, training and deskilling. Pharmacists also believed that adherence to the OCP was generally good and that their role was limited to dispensing medication and providing information when asked. There are contrasting perspectives between contraception service providers and contraceptive users. Training for healthcare providers is required to support informed contraceptive choice and adherence. It is necessary to address the practice barriers of cost and lack of time, to promote better communication around adherence issues and prescription contraception options. There is a need for more easily-accessible public health information to promote awareness on all methods of prescription contraception.

Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in human breast milk and associated health risks to nursing infants in Northern Tanzania.

PubMed

Müller, M H B; Polder, A; Brynildsrud, O B; Karimi, M; Lie, E; Manyilizu, W B; Mdegela, R H; Mokiti, F; Murtadha, M; Nonga, H E; Skaare, J U; Lyche, J L

2017-04-01

This is the first study to report organochlorines (OCs), including chlorinated pesticides (OCPs) and polychlorinated biphenyls (PCBs) in human milk from Tanzania. The main aims of this study were to assess the level of contamination and the possible health risks related to OC exposure in nursing infants from the Northern parts of Tanzania. Ninety-five healthy mother-infant couples attending Mount Meru Regional Referral Hospital (MMRRH), Arusha, Tanzania, were assessed for associations between maternal/infant characteristics, i.e. mother's age, BMI, gestational weight gain, occupation, residence and fetal growth parameters and breast milk levels of OCPs, such as dichlorodiphenyltrichloroethane (DDT) and its metabolites, dieldrin and PCBs. p,p'-DDE and p,p'-DDT were detected in 100% and 75% of the breast milk samples, respectively, and ranged between 24 and 2400ng/g lipid weight (lw) and

Organochlorine pesticides and thiamine in eggs of largemouth bass and American alligators and their relationship with early life-stage mortality.

PubMed

Sepúlveda, Maria S; Wiebe, Jon J; Honeyfield, Dale C; Rauschenberger, Heath R; Hinterkopf, Joy P; Johnson, William E; Gross, Timothy S

2004-10-01

Thiamine deficiency has been linked to early mortality syndrome in salmonids in the Great Lakes. This study was conducted to compare thiamine concentrations in American alligators (Alligator mississippiensis) and Florida largemouth bass (Micropterus salmoides floridanus) eggs from sites with high embryo mortality and high exposure to organochlorine pesticides (OCPs) (Lakes Apopka and Griffin, and Emeralda Marsh, Florida, USA) to those from sites that have historically exhibited low embryo mortality and low OCPs (Lakes Woodruff and Orange, Florida). During June-July 2000, 20 alligator clutches were collected from these sites, artificially incubated, and monitored for embryo mortality. Thiamine and OCPs were measured in one egg/clutch. During February 2002, 10 adult female bass were collected from Emeralda Marsh and Lake Woodruff and mature ovaries analyzed for thiamine and OCP concentrations. Although ovaries from the Emeralda Marsh bass contained almost 1,000-fold more OCPs compared with the reference site, Lake Woodruff, there were no differences in thiamine concentrations between sites (11,710 vs. 11,857 pmol/g). In contrast, alligator eggs from the reference site had five times the amount of thiamine compared with the contaminated sites (3,123 vs. 617 pmol/g). Similarly, clutches with >55% hatch rates had significantly higher concentrations of thiamine compared with clutches with <54% hatch rates (1,119 vs. 201 pmol/g). These results suggest that thiamine deficiency might be playing an important role in alligator embryo survival but not in reproductive failure and recruitment of largemouth bass. The cause(s) of this thiamine deficiency are unknown but might be related to differences in the nutritional value of prey items across the sites studied and/or to the presence of high concentration of contaminants in eggs.

Preliminary investigation of the relationships between sleep duration, reward circuitry function, and mood dysregulation in youth offspring of parents with bipolar disorder.

PubMed

Soehner, Adriane M; Bertocci, Michele A; Manelis, Anna; Bebko, Genna; Ladouceur, Cecile D; Graur, Simona; Monk, Kelly; Bonar, Lisa K; Hickey, Mary Beth; Axelson, David; Goldstein, Benjamin I; Goldstein, Tina R; Birmaher, Boris; Phillips, Mary L

2016-11-15

Altered reward circuitry function is observed in individuals with bipolar disorder (BD) and their unaffected offspring (OBP). While OBP are at elevated risk for BD, modifiable risk factors that may exacerbate neural vulnerabilities in OBP remain under-characterized. As sleep loss is strongly linked to mania in BD, this study tested associations between sleep duration, reward circuitry function, and mood dysregulation in OBP. Two groups of youth unaffected with BD (9-17yr) completed a number-guessing fMRI reward paradigm: 25 OBP and 21 age-sex-IQ-matched offspring of control parents with non-BD psychopathology (OCP), to differentiate risk for BD from risk for psychopathology more broadly. Regressions tested effects of group status, self-reported past-week sleep duration, and their interaction on neural activity and bilateral ventral striatum (VS) functional connectivity to win>control. Correlations with parent-reported mood dysregulation were assessed. Group effects were observed for right posterior insula activity (OCP>OBP) and VS-left posterior insula connectivity (OBP>OCP). Group ⁎ sleep duration interactions were observed for left dorsal anterior-mid-cingulate (daMCC) activity and VS-left anterior insula/ventrolateral prefrontal cortex (VLPFC) connectivity. Specifically, sleep duration and daMCC activity were positively related in OBP, but negatively related in OCP and sleep duration and VS-left anterior insula/VLPFC connectivity were negatively related in OBP, but positively in OCP. Additionally, increased VS-left posterior insula connectivity and VS-left anterior insula/VLPFC connectivity were associated with greater mood dysregulation in OBP only. Cross-sectional design and small sample size. Altered reward-related VS-insula connectivity could represent a neural pathway underpinning mood dysregulation in OBP, and may be modulated by shortened sleep duration. Copyright © 2016 Elsevier B.V. All rights reserved.

Necropsy findings in American alligator late-stage embryos and hatchlings from northcentral Florida lakes contaminated with organochlorine pesticides

USGS Publications Warehouse

Sepulveda, M.S.; Del, Piero F.; Wiebe, J.J.; Rauschenberger, H.R.; Gross, T.S.

2006-01-01

Increased American alligator (Alligator mississippiensis) embryo and neonatal mortality has been reported from several northcentral Florida lakes contaminated with old-use organochlorine pesticides (OCPs). However, a clear relationship among these contaminants and egg viability has not been established, suggesting the involvement of additional factors in these mortalities. Thus, the main objective of this study was to determine the ultimate cause of mortality of American alligator late-stage embryos and hatchlings through the conduction of detailed pathological examinations, and to evaluate better the role of OCPs in these mortalities. Between 2000 and 2001, 236 dead alligators were necropsied at or near hatching (after ???65 days of artificial incubation and up to 1 mo of age posthatch). Dead animals were collected from 18 clutches ranging in viability from 0% to 95%. Total OCP concentrations in yolk ranged from ???100 to 52,000 ??g/kg, wet weight. The most common gross findings were generalized edema (34%) and organ hyperemia (29%), followed by severe emaciation (14%) and gross deformities (3%). Histopathologic examination revealed lesions in 35% of the animals, with over half of the cases being pneumonia, pulmonary edema, and atelectasis. Within and across clutches, dead embryos and hatchlings compared with their live cohorts were significantly smaller and lighter. Although alterations in growth and development were not related to yolk OCPs, there was an increase in prevalence of histologic lesions in clutches with high OCPs. Overall, these results indicate that general growth retardation and respiratory abnormalities were a major contributing factor in observed mortalities and that contaminants may increase the susceptibility of animals to developing certain pathologic conditions. ?? Wildlife Disease Association 2006.

Polycyclic aromatic hydrocarbons and organochlorine pesticides in surface soils from the Qinghai-Tibetan plateau.

PubMed

Tao, Shu; Wang, Wentao; Liu, Wenxin; Zuo, Qian; Wang, Xilong; Wang, Rong; Wang, Bin; Shen, Guofeng; Yang, Yuanhe; He, Jin-shen

2011-01-01

Eighty eight surface soil samples were collected from the Qinghai-Tibetan Plateau (QTP) for determination of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs), including dichlorodiphenyltrichloroethane and metabolites (DDXs) and hexachlorocyclohexane isomers (HCHs). The measured concentrations were 51.8 ± 38.5 ng g(-1), 0.329 ± 0.818 ng g(-1), and 0.467 ± 0.741 ng g(-1) as means and standard deviations of PAHs, DDXs, and HCHs, respectively, which were 1-2 orders of magnitude lower than those reported for eastern China. Significant differences were also revealed among four sub-areas within QTP. PAHs detected in the samples from the remote sub-areas of T'ang-ku-la/Hoh Xil Mountains and along the Qinghai-Tibet highway in the west and northwest of QTP were 1 order of magnitude lower than those from Lhasa and east Qinghai. The differences in soil OCPs among the sub-areas were 2-7 times. Soil PAHs were significantly correlated with emission density and soil organic carbon content (SOC), while OCPs were correlated significantly with the population density and SOC. Based on the calculated backward air mass trajectories and geographical distributions of emission and population, it was revealed that PAHs and OCPs accumulated in the soils in the west and northwest QTP were primarily from long-range transport and may represent the background levels of East Asia. This part of QTP can also serve as an important receptor area for regional or even global long-range transport study. The elevated concentrations of PAHs and OCPs in Lhasa and east Qinghai were mainly from local sources, while PAHs from adjacent Lanzhou area also contributed considerably to the accumulation of PAHs in east Qinghai.

Application of an octa-anionic 5,10,15,20-tetra[3,5-(nido-carboranylmethyl)phenyl]porphyrin (H2OCP) as dual sensitizer for BNCT and PDT

USDA-ARS?s Scientific Manuscript database

The applications of the octa-anionic 5,10,15,20-tetra[3,5-(nidocarboranylmethyl) phenyl]porphyrin (H2OCP) as a boron delivery agent in boron neutron capture therapy (BNCT) and a photosensitizer in photodynamic therapy (PDT) have been investigated. Using F98 Rat glioma cells, we evaluated the cytotox...

Metformin versus oral contraceptive pill in polycystic ovary syndrome: a Cochrane review.

PubMed

Costello, Michael F; Shrestha, Bhushan; Eden, John; Johnson, Neil P; Sjoblom, Peter

2007-05-01

The object of this review was to compare metformin versus oral contraceptive pill (OCP) treatment in polycystic ovary syndrome. A systematic review and meta-analysis employing the principles of the Cochrane Menstrual Disorders and Subfertility Group was undertaken. Four randomized controlled trials (RCTs) (104 subjects) were included. Limited data demonstrated no evidence of a difference in effect between metformin and the OCP on hirsutism, acne or development of type 2 diabetes mellitus. There were no trials assessing diagnosis of cardiovascular disease or endometrial cancer. Metformin, in comparison with the OCP, was less effective in improving menstrual pattern [Peto odds ratio (OR) 0.08, 95% confidence interval (CI) 0.01-0.45) and in reducing the serum total testosterone level weighted mean difference (WMD) 0.54, 95% CI 0.22-0.86] but more effective in reducing fasting insulin (WMD -3.46, 95% CI - 5.39 to -1.52) and not increasing fasting triglyceride (WMD -0.48, 95% CI - 0.86 to -0.09) levels. Limited data demonstrated no evidence of a difference in effect between the two therapies on reducing fasting glucose or total cholesterol levels and severe adverse events. The limited RCT evidence to date does not show adverse metabolic risk with the use of the OCP compared with metformin. Further long-term RCTs are required.

Risk profile and health vulnerability of female workers who pick cotton by organanochlorine pesticides from southern Punjab, Pakistan.

PubMed

Yasmeen, Humaira; Qadir, Abdul; Mumtaz, Mehvish; Eqani, Syed Ali Musstjab Akber Shah; Syed, Jabbir Hussain; Mahmood, Adeel; Jamil, Nadia; Nazar, Farva; Ali, Habib; Ahmad, Muhammad Shafiq; Tanveer, Zafar Iqbal; Zhang, Gan

2017-05-01

The present study was conducted to highlight the existing level of organochlorine-pesticides (OCPs) from human milk (n = 45) and blood serum (n = 40) of female workers who pick cotton in Khanewal District, southern Punjab, Pakistan. Source apportionment, congener-specific analysis, and risk surveillance of OCPs are reported from human milk and blood samples. Levels of OCPs in milk and blood serum samples ranged from 15.7 ppb to 538.3 ppb and from 16.4 ppb to 747.1 ppb, respectively, and were lower than previously published reports from other regions of the globe. Congener-specific analysis revealed that DDTs were predominant, followed by hexachlorocyclohexane, chlordane, and hexachlorobenzene. Calculated results for source apportionment analysis suggested that contamination load was a new input of DDTs as well as the historic use of lindane in the study area. Levels of OCPs in milk and blood serum were significantly (p < 0.05) correlated with age, time period of picking cotton, and number of children. Health risk revealed that female workers had risk of cancer among 1 per million; however, noncarcinogenic risks were not considerable. Environ Toxicol Chem 2017;36:1193-1201. © 2016 SETAC. © 2016 SETAC.

The new extended-cycle levonorgestrel-ethinyl estradiol oral contraceptives.

PubMed

Bonnema, Rachel A; Spencer, Abby L

2011-09-19

Effective contraceptive counseling requires an understanding of a woman's preferences and medical history as well as the risks, benefits, side effects, and contraindications of each contraceptive method. Hormonal contraceptives using a variety of delivery methods are highly effective and this review highlights the new extended-cycle levonorgestrel-ethinyl estradiol contraceptives. Extended-cycle OCPs are unique in offering fewer or no withdrawal bleeds over the course of one year but providers need to carefully counsel women regarding the initial increased breakthrough bleeding. Extended-cycle OCPs may be of particular benefit in women with medical comorbidities who would benefit from less withdrawal bleeds, those desiring to avoid monthly menses due to increased hormonal withdrawal symptoms, or simply women who don't desire a monthly period. The risks associated with all extended-cycle OCPs have been found to be similar to those of traditional OCPs therefore counseling on the risks and side effects is comparable to that of any combined hormonal contraceptives. Newer extended-cycle regimens shorten or eliminate the hormone-free interval, decrease frequency of menses to four times per year or eliminate menses altogether. This can reduce the risk of common menstrual symptoms, endometriosis, or severe dysmenorrhea by offering potentially greater ovarian suppression and preventing endogenous estradiol production while still providing highly effective, rapidly reversible, and safe contraception.

Study of Intermediate Age (~10-30 Myr) Open Clusters

NASA Astrophysics Data System (ADS)

Olguin, Lorenzo; Michel, Raul; Contreras, Maria; Hernandez, Jesus; Schuster, William; Chavarria-Kleinhenn, Carlos

2013-07-01

We present the study of a sample of intermediate age open clusters (age ~ 10-30 Myr) using optical (UBVRI) and infrared photometric data. Optical photometry was obtained as part of the San Pedro Martir Open Clusters Project (SPM-OCP, Schuster et al. 2007; Michel et al. 2013). Infrared photometry was retrieved from 2MASS public data archive and WISE database. Open clusters included in the SPM-OCP were selected from catalogues presented by Dias et al. (2002) and Froebrich, Scholz & Raftery (2007). One of the main goals of the SPM-OCP is to compile a self-consistent and homogeneous set of cluster fundamental parameters such as reddening, distance, age, and metallicity whenever possible. In this work, we have analyzed a set of 25 clusters from the SPM-OCP with estimated ages between 10 and 30 Myr. Derived fundamental parameters for each cluster in the sample as well as an example of typical color-color and color-magnitude diagrams are presented. Kinematic membership was established by using proper motion data taken from the literature. Based on infrared photometry, we have searched for candidate stars to posses a circumstellar disk within each clusters. For those selected candidates a follow-up spectroscpic study is being carried out. This work was partially supported by UNAM-PAPIIT grant IN-109311.

[Preparation and certification of mussel reference material for organochlorine pesticides and polychlorinated biphenyls using isotope dilution-high resolution mass spectrometry].

PubMed

Lu, Xianbo; Chen, Jiping; Wang, Shuqiu; Zou, Lili; Tian, Yuzeng; Ni, Yuwen; Su, Fan

2012-09-01

A method for the preparation and certification of the reference material of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in mussel tissue is described. The mussel tissue from Dalian Bay was frozen-dried, comminuted, sieved, homogenized, packaged, and sterilized by 60Co radiation sterilization in turn. The certified values for 18 OCPs and 16 PCBs were determined by high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) using isotope dilution and internal standard quantitation techniques. The certified values were validated and given based on seven accredited laboratories, and these values are traceable to the SI (international system of units) through gravimetrically prepared standards of established purity and measurement intercomparisons. The certified values of PCBs and OCPs in mussel span 4 orders of magnitude with a relative uncertainty of about 10%. This material is a natural biological material with confirmed good homogeneity and stability, and it was approved as the grade "primary reference material" (GBW10069) in June 2012 in China. This reference material provided necessary quality control products for our country to implement the Stockholm Treaty on the monitoring of persistent organic pollutants (POPs). The material is intended to be used for the method validation and quality control in the determination of OCPs and PCBs in biota samples.

Optical properties of mouse brain tissue after optical clearing with FocusClear™

NASA Astrophysics Data System (ADS)

Moy, Austin J.; Capulong, Bernard V.; Saager, Rolf B.; Wiersma, Matthew P.; Lo, Patrick C.; Durkin, Anthony J.; Choi, Bernard

2015-09-01

Fluorescence microscopy is commonly used to investigate disease progression in biological tissues. Biological tissues, however, are strongly scattering in the visible wavelengths, limiting the application of fluorescence microscopy to superficial (<200 μm) regions. Optical clearing, which involves incubation of the tissue in a chemical bath, reduces the optical scattering in tissue, resulting in increased tissue transparency and optical imaging depth. The goal of this study was to determine the time- and wavelength-resolved dynamics of the optical scattering properties of rodent brain after optical clearing with FocusClear™. Light transmittance and reflectance of 1-mm mouse brain sections were measured using an integrating sphere before and after optical clearing and the inverse adding doubling algorithm used to determine tissue optical scattering. The degree of optical clearing was quantified by calculating the optical clearing potential (OCP), and the effects of differing OCP were demonstrated using the optical histology method, which combines tissue optical clearing with optical imaging to visualize the microvasculature. We observed increased tissue transparency with longer optical clearing time and an analogous increase in OCP. Furthermore, OCP did not vary substantially between 400 and 1000 nm for increasing optical clearing durations, suggesting that optical histology can improve ex vivo visualization of several fluorescent probes.

Estradiol and Antagonist Pretreatment Prior to Microdose Leuprolide in in Vitro Fertilization. Does It Improve IVF Outcomes in Poor Responders as Compared to Oral Contraceptive Pill?

PubMed

Elassar, Alyaa; Nulsen, John; Engmann, Lawrence; Benadiva, Claudio

2015-01-01

To compare in vitro fertilization (IVF) outcomes in low responders stimulated with microdose leuprolide protocol (ML) following pretreatment with either oral contraceptive pill (OCP) or luteal estradiol (E2) + GnRH antagonist (E2 + antag) for follicular synchronization prior to controlled ovarian hyperstimulation (COH). This was a retrospective study of 130 women, who were poor responders, undergoing IVF with either OCP/ML or E2+ antag/ML protocols. The main outcome measures were ongoing pregnancy rates, number of oocytes retrieved, and cancellation rate. Both groups were similar in baseline characteristics. There were no significant differences in gonadotropin requirement, cancellation rate, and number of embryos transferred. Ongoing pregnancy rates (40% vs. 15%) were significantly higher in the OCP/ML group. Trends toward greater number of oocytes retrieved (7.7 ± 3.4 vs. 5.9 ± 4.2) and improved implantation rates (20% vs. 12%) were also noted, but these did not reach statistical significance. E2+antag pretreatment does not appear to improve IVF outcomes in ML protocol when compared to the standard OCP in poor responders. Randomized trials with adequate power to study the optimal method of steroid pretreatments appear justified.

In vitro and in vivo mechanical evaluations of plasma-sprayed hydroxyapatite coatings on titanium implants: the effect of coating characteristics.

PubMed

Yang, C Y; Lin, R M; Wang, B C; Lee, T M; Chang, E; Hang, Y S; Chen, P Q

1997-12-05

This study was undertaken to evaluate the effect of coating characteristics on the mechanical strengths of the plasma-sprayed HA-coated Ti-6Al-4V implant system both in vitro and in vivo. Two types of HA coatings (HACs) with quite different microstructures, concentrations of impurity-phases, and indices-of-crystallinity were used. In vitro testings were done by measuring the bonding-strength at the Ti-6Al-4V-HAC interface, with HACs that had and had not been immersed in a pH-buffered, serum-added simulated body fluid (SBF). The shear-strength at the HAC-bone interface was investigated in a canine transcortical femoral model after 12 and 24 weeks of implantation. The results showed a bonding degradation of approximately 32% or higher of the original strength after 4 weeks of immersion in SBF, and this predominantly depended on the constructed microstructure of the HACs. After the push-out measurements, it was demonstrated that the HACs with higher bonding-strength in vitro would correspondingly result in significantly higher shear-strength at each implant period in vivo. Nevertheless, there were no substantial histological variations between the two types of HACs evaluated. The most important point elucidated in this study was that, among coating characteristics, the microstructure was the key factor in influencing the mechanical stability of the HACs both in vitro and in vivo. As a consequence, a denser HAC was needed to ensure mechanical stability at both interfaces.

Calcium Phosphate Growth at Electropolished Titanium Surfaces

PubMed Central

Ajami, Elnaz; Aguey-Zinsou, Kondo-Francois

2012-01-01

This work investigated the ability of electropolished Ti surface to induce Hydroxyapatite (HA) nucleation and growth in vitro via a biomimetic method in Simulated Body Fluid (SBF). The HA induction ability of Ti surface upon electropolishing was compared to that of Ti substrates modified with common chemical methods including alkali, acidic and hydrogen peroxide treatments. Our results revealed the excellent ability of electropolished Ti surfaces in inducing the formation of bone-like HA at the Ti/SBF interface. The chemical composition, crystallinity and thickness of the HA coating obtained on the electropolished Ti surface was found to be comparable to that achieved on the surface of alkali treated Ti substrate, one of the most effective and popular chemical treatments. The surface characteristics of electropolished Ti contributing to HA growth were discussed thoroughly. PMID:24955535

Using state-and-transition modeling to account for imperfect detection in invasive species management

USGS Publications Warehouse

Frid, Leonardo; Holcombe, Tracy; Morisette, Jeffrey T.; Olsson, Aaryn D.; Brigham, Lindy; Bean, Travis M.; Betancourt, Julio L.; Bryan, Katherine

2013-01-01

Buffelgrass, a highly competitive and flammable African bunchgrass, is spreading rapidly across both urban and natural areas in the Sonoran Desert of southern and central Arizona. Damages include increased fire risk, losses in biodiversity, and diminished revenues and quality of life. Feasibility of sustained and successful mitigation will depend heavily on rates of spread, treatment capacity, and cost–benefit analysis. We created a decision support model for the wildland–urban interface north of Tucson, AZ, using a spatial state-and-transition simulation modeling framework, the Tool for Exploratory Landscape Scenario Analyses. We addressed the issues of undetected invasions, identifying potentially suitable habitat and calibrating spread rates, while answering questions about how to allocate resources among inventory, treatment, and maintenance. Inputs to the model include a state-and-transition simulation model to describe the succession and control of buffelgrass, a habitat suitability model, management planning zones, spread vectors, estimated dispersal kernels for buffelgrass, and maps of current distribution. Our spatial simulations showed that without treatment, buffelgrass infestations that started with as little as 80 ha (198 ac) could grow to more than 6,000 ha by the year 2060. In contrast, applying unlimited management resources could limit 2060 infestation levels to approximately 50 ha. The application of sufficient resources toward inventory is important because undetected patches of buffelgrass will tend to grow exponentially. In our simulations, areas affected by buffelgrass may increase substantially over the next 50 yr, but a large, upfront investment in buffelgrass control could reduce the infested area and overall management costs.

In vivo performance of two different hydroxyapatite coatings on titanium prepared by discharging in electrolytes.

PubMed

Yamamoto, Hiroki; Shibata, Yo; Tachikawa, Tetsuhiko; Miyazaki, Takashi

2006-07-01

This study reports a discharging method for bone-like carbonated HA (cHA)-coating (Ca/P 1.71) and stoichiometric HA (sHA)-coating (Ca/P 1.67) with micrometer order thicknesses on titanium plates, using modified body fluid and acidic calcium phosphate solutions, respectively. In vivo histological performance of the HA coatings prepared by discharging in electrolytes was evaluated. Bone-contact indexes of HA coatings were measured microscopically. Additionally, bone-coating interface was analyzed by scanning electron microscopy and the use of an electron probe microanalyzer. Results demonstrated that there was no significant difference in contact index between HA coatings. However, the cHA coating was practically replaced by immature bone, and the titanium metal substrate was directly connected to the bone structure whereas the sHA coating layer remained and was partially detached from the titanium metal substrate. Since detached coating particles are pathogens, and can cause peri-implantitis, the cHA coating was more favorable than the sHA coating even if contact index was equivalent to that of the sHA coating. It is thought that coating thickness and chemical composition of coatings are important for biological stability of implants. In conclusion, since bone-like thin cHA coating showed high osteoconductivity and bone replacement, bone-like HA is superior to sHA coating for use in dental implants.

Comparison of Norethindrone-Containing OCPs to Desogestrel OCPs and Depo-Provera in Women

DTIC Science & Technology

2000-10-01

induces amenorrhea (12,20-26). To date, however, no study has directly compared continuation rates among these different methods of contraception. The...height physical standards unique to their branch of the armed forces after long term use. Although consistent exercise may help control this weight gain...a willingness to exercise may be impeded by DMPA use as preliminary studies suggest that this method results in increased fatigue (32). Other issues

Distribution and uptake pathways of organochlorine pesticides in greenhouse and conventional vegetables.

PubMed

Zhang, Anping; Luo, Wenxiu; Sun, Jianqiang; Xiao, Hang; Liu, Weiping

2015-02-01

The application of greenhouse vegetable cultivation has dramatically expanded worldwide during the last several decades. However, little information is available on the distribution and uptake of pesticides in greenhouse vegetables. To bridge this knowledge gap, the present study was initiated to investigate the distribution and uptake of organochlorine pesticides (OCPs) in vegetables from plastic greenhouse and conventional cultivation methods. The uptake pathways of OCPs were not significantly different between these two cultivation methods. The arithmetic means of OCP concentrations in greenhouse vegetables were higher than those in conventional vegetables, although there was no significant difference. This small difference raised the concern of whether the tiny difference could be magnified to a significant difference by bioaccumulation in the food chain. The issue should be addressed by a well-designed scheme in future studies. Copyright © 2014 Elsevier B.V. All rights reserved.

Deposition of organochlorine pesticides, PCBs (Aroclor 1268), and PBDEs in selected plant species from a Superfund Site at Brunswick, Georgia, USA.

PubMed

Sajwan, Kenneth S; Senthil Kumar, Kurunthachalam; Kelley, Sarah; Loganathan, Bommanna G

2009-04-01

Deposition of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were measured in Loblolly pine needles (Pinus taeda) collected in and around a Linden Chemicals and Plastics (LCP) Superfund Site at Brunswick, Georgia, USA. For the comparison, foliage of eastern red cedar (Juniperus virginiana) was also collected to monitor contaminant levels. This study revealed that concentrations of OCPs, PCBs and PBDEs ranged from 0.75-10, 3.4-15 to 0.05-3, ng/g wet wt, respectively in both plant species. Total OCPs concentrations in pine needles decreased from 10 to 2.3 ng/g; and total PCBs decreased from 28 to 9.3 ng/g between 1997 and 2006. To our knowledge, this is the first report on PBDEs concentrations in pine needles and red cedar foliage samples from the Superfund Site at Brunswick, Georgia, USA.

Drospirenone/ethinyl estradiol 3 mg/20 μg (24/4 day regimen): hormonal contraceptive choices – use of a fourth-generation progestin

PubMed Central

Bachmann, Gloria; Kopacz, Sharon

2009-01-01

The combined oral contraceptive pill (COC) consisting of drospirenone 3 mg/ethinyl estradiol 20 μg (3 mg DRSP/20 μg EE-24/4) supplies 24 days of pills with hormones followed by 4 days of hormone-free pills. This regimen is called the 24/4 regimen. The progesterone component of this oral contraceptive pill (OCP), drospirenone (DRSP), is a fourth-generation progestin that has potent progestogenic, antimineralocorticoid, and antiandrogenic activity, which are unique characteristics compared with the other progestogens contained in most of the other OCPs currently marketed. This formulation, in addition to being an effective long-term OCP, has the additional medical benefit of providing a good parallel treatment for premenstrual dysphoric disorder and moderate acne. The effectiveness of 3 mg DRSP/20 μg EE-24/4, its tolerability and safety, and its additional non-contraceptive benefits are discussed. PMID:19936169

Structural characterization of nanocrystalline hydroxyapatite and adhesion of pre-osteoblast cells

NASA Astrophysics Data System (ADS)

Zhu, Xiaolong; Eibl, Oliver; Berthold, Christoph; Scheideler, Lutz; Geis-Gerstorfer, Jürgen

2006-06-01

Nanocrystalline hydroxyapatite (Nano HA), a prototype of minerals of bones and teeth, attracts increasing interest in medicine and dentistry. Different parameters for synthesis and post-treatment were investigated to determine their effects on crystallinity of nano HA, and in vitro cell responses to nano HA were studied. XRD and TEM analyses indicate that the crystallinity of nano HA synthesized by a chemical method was within the range of 15-50 nm, which is adapted to natural minerals of hard tissues. Increasing the ageing temperature significantly increased the crystallinity of nano HA, while lengthening the ageing time or varying the post-ageing drying process did not have any influence on its crystallinity. Nano HA annealed between 300 and 900 °C showed a small increase in crystallinity with increasing annealing temperature due to the long-range ordering effect. Cell attachment and spreading on nano HA were lower than those on pure titanium, and decreased as the crystallinity of nano HA increased. However, cells on nano HA demonstrated well-developed filopodia and lamelliopodia, which facilitate migration of the cells on it. This may benefit osteogenesis at the interface between bone and nano HA in vivo.

Performance improvement of optical CDMA networks with stochastic artificial bee colony optimization technique

NASA Astrophysics Data System (ADS)

Panda, Satyasen

2018-05-01

This paper proposes a modified artificial bee colony optimization (ABC) algorithm based on levy flight swarm intelligence referred as artificial bee colony levy flight stochastic walk (ABC-LFSW) optimization for optical code division multiple access (OCDMA) network. The ABC-LFSW algorithm is used to solve asset assignment problem based on signal to noise ratio (SNR) optimization in OCDM networks with quality of service constraints. The proposed optimization using ABC-LFSW algorithm provides methods for minimizing various noises and interferences, regulating the transmitted power and optimizing the network design for improving the power efficiency of the optical code path (OCP) from source node to destination node. In this regard, an optical system model is proposed for improving the network performance with optimized input parameters. The detailed discussion and simulation results based on transmitted power allocation and power efficiency of OCPs are included. The experimental results prove the superiority of the proposed network in terms of power efficiency and spectral efficiency in comparison to networks without any power allocation approach.

In vitro and in vivo performance of bioactive Ti6Al4V/TiC/HA implants fabricated by a rapid microwave sintering technique.

PubMed

Choy, Man Tik; Tang, Chak Yin; Chen, Ling; Wong, Chi Tak; Tsui, Chi Pong

2014-09-01

Failure of the bone-implant interface in a joint prosthesis is a main cause of implant loosening. The introduction of a bioactive substance, hydroxyapatite (HA), to a metallic bone-implant may enhance its fixation on human bone by encouraging direct bone bonding. Ti6Al4V/TiC/HA composites with a reproducible porous structure (porosity of 27% and pore size of 6-89 μm) were successfully fabricated by a rapid microwave sintering technique. This method allows the biocomposites to be fabricated in a short period of time under ambient conditions. Ti6Al4V/TiC/HA composites exhibited a compressive strength of 93 MPa, compressive modulus of 2.9 GPa and microhardness of 556 HV which are close to those of the human cortical bone. The in vitro preosteoblast MC3T3-E1 cells cultured on the Ti6Al4V/TiC/HA composite showed that the composite surface could provide a biocompatible environment for cell adhesion, proliferation and differentiation without any cytotoxic effects. This is among the first attempts to study the in vivo performance of load-bearing Ti6Al4V/TiC and Ti6Al4V/TiC/HA composites in a live rabbit. The results indicated that the Ti6Al4V/TiC/HA composite had a better bone-implant interface compared with the Ti6Al4V/TiC implant. Based on the microstructural features, the mechanical properties, and the in vitro and in vivo test results from this study, the Ti6Al4V/TiC/HA composites have the potential to be employed in load-bearing orthopedic applications. Copyright © 2014 Elsevier B.V. All rights reserved.

Identification of small molecule compounds targeting the interaction of HIV-1 Vif and human APOBEC3G by virtual screening and biological evaluation.

PubMed

Ma, Ling; Zhang, Zhixin; Liu, Zhenlong; Pan, Qinghua; Wang, Jing; Li, Xiaoyu; Guo, Fei; Liang, Chen; Hu, Laixing; Zhou, Jinming; Cen, Shan

2018-05-23

Human APOBEC3G (hA3G) is a restriction factor that inhibits human immunodeficiency 1 virus (HIV-1) replication. The virally encoded protein Vif binds to hA3G and induces its degradation, thereby counteracting the antiviral activity of hA3G. Vif-mediated hA3G degradation clearly represents a potential target for anti-HIV drug development. Herein, we have performed virtual screening to discover small molecule inhibitors that target the binding interface of the Vif/hA3G complex. Subsequent biochemical studies have led to the identification of a small molecule inhibitor, IMB-301 that binds to hA3G, interrupts the hA3G-Vif interaction and inhibits Vif-mediated degradation of hA3G. As a result, IMB-301 strongly inhibits HIV-1 replication in a hA3G-dependent manner. Our study further demonstrates the feasibility of inhibiting HIV replication by abrogating the Vif-hA3G interaction with small molecules.

The biomechanical behavior on the interface of tumor arthrosis/allograft prosthetic composite by finite element analysis

NASA Astrophysics Data System (ADS)

Chen, H. Z.; Jiang, W.; Zou, W.; Luo, J. M.; Chen, J. Y.; Tu, C. Q.; Xing, B. B.; Gu, Z. W.; Zhang, X. D.

2008-11-01

The biomechanical behavior of the uniting interface between the allograft bone and the autogenetic bone plays an important role in the treatment of the proximal femur massive defects with artificial tumor arthrosis/allograft prosthetic composite (TAAPC). According to the CT data of a patient, a 3D medical treatment model of TAAPC was established. Under the loads of 1.5 and 2.5 times standard body weight (70 kg), the mechanical behavior of the treatment model was analyzed by finite element analysis (FEA) for three typical healing periods. The results show that there are significant differences in the stress values and distribution in different healing periods. With healing of osteotomy, the hardness of the tissue of the uniting interface increases, the stress in uniting area was increased greatly and the stress concentration decreased. After cured the stress almost reached the level of normal bone. In the initial stage of healing, the healing training is not encouraged because there is an obvious risk of fracture of prosthesis and bone cement. In addition, porous hydroxyapatite (HA) ceramic used as bone tissue scaffold for this case, not only facilitates the generation of new bone, but also can avoid this risk caused by the non-uniting interface.

Monitoring and risk assessment of pesticides in irrigation systems in Debra Zeit, Ethiopia.

PubMed

Teklu, Berhan M; Adriaanse, Paulien I; Van den Brink, Paul J

2016-10-01

Since Ethiopia is going through a rapid transformation of its agricultural sector, we assessed the human health and environmental risks due to the past use of organochlorine pesticides (OCPs) as well as the risks of the current pesticide use by farmers. A monitoring programme and risk assessment was carried out for the Wedecha-Belbela irrigation system in the Debra Zeit area. The Wedecha and Belbela rivers and adjacent temporary ponds were sampled and examined for the presence of OCPs between August and October 2014, while data on the current pesticide use by small- and large-scale farmers was collected by interviews. The usage patterns were evaluated for risks of using the river or temporary ponds as source of drinking water and for risks for the aquatic ecosystems in the river and ponds with the aid of the PRIMET_Registration_Ethiopa_1.1 model. The samples were collected in five sampling periods, and results indicate that most of the 18 target OCPs were not detected above the detection limit, while g-chlordane may pose chronic risks when surface water is used as drinking water. Endosulfan and heptachlor pose risks to aquatic organisms at second-tier level, while for heptachlor-epoxide B, g-chlordane and b-BHC only risks could be determined at the first tier due to a lack of data. For all nine pesticides used by small-scale farmers the calculated acute risks to humans were low. Second tier risk assessment for the aquatic ecosystem indicated that lambda-cyhalothrin, endosulfan, profenofos, and diazinon may pose high risks. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparison of Norethindrone-Containing OCPs to Desogestrel OCPs and Depro-Provera in Women

DTIC Science & Technology

1999-10-01

it is easy to use or because it induces amenorrhea (12,20-26). To date, however, no study has directly compared continuation rates among these... exercise may help control this weight gain, a willingness to exercise may be impeded by DMPA use as preliminary studies suggest that this method results...not induce cyclic bleeding, as with DMPA (33). Irregular bleeding may also occur with use of hormonal contraception. However, the frequency of

Carbon fluxes in the Arabian Sea: Export versus recycling

NASA Astrophysics Data System (ADS)

Rixen, Tim; Gaye, Birgit; Ramaswamy, Venkitasubramani

2016-04-01

The organic carbon pump strongly influences the exchange of carbon between the ocean and the atmosphere. It is known that it responds to global change but the magnitude and the direction of change are still unpredictable. Sediment trap experiments carried out at various sites in the Arabian Sea between 1986 and 1998 have shown differences in the functioning of the organic carbon pump (OCP). An OCP driven by eukaryotic phytoplankton operated in the upwelling region off Oman and during the spring bloom in the northern Arabian Sea. Cyanobacteria capable of fixing nitrogen seem to dominate the phytoplankton community during all other seasons. The export driven by cyanobacteria was much lower than the export driven by eukaryotic phytoplankton. Productivity and nutrient availability seems to be a main factor controlling fluxes during blooms of eukaryotic phytoplankton. The ballast effect caused by inputs of dust into the ocean and its incorporation into sinking particles seems to be the main factor controlling the export during times when cyanobacteria dominate the phytoplankton community. C/N ratios of organic matter exported from blooms dominated by nitrogen fixing cyanobacteria are enhanced and, furthermore, indicate a more efficient recycling of nutrients at shallower water depth. This implies that the bacterial-driven OCP operates more in a recycling mode that keeps nutrients closer to the euphotic zone whereas the OCP driven by eukaryotic phytoplankton reduces the recycling of nutrients by exporting them into greater water-depth.

Levels of Polycyclic Aromatic Hydrocarbons, Polychlorinated Biphenyls, and Organochlorine Pesticides in Various Tissues of White-Backed Vulture in India

PubMed Central

Dhananjayan, V.; Muralidharan, S.

2013-01-01

This study provides information on the current status of contamination by polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) in the tissues of endangered White-backed Vulture Gyps bengalensis in India. Chemical analyses revealed detectable amounts of PAHs, PCBs, and OCPs. Concentration ranges of ∑PAHs, ∑PCBs, and ∑OCPs in tissues were 60–2037 ng/g, 30–5790 ng/g, and 3.2–5836 ng/g wet weight, respectively. 1,1-Dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p′-DDE) concentrations ranged from below detectable level to 599 ng/g wet weight, representing more than 90% of the total dichlorodiphenyltrichloroethane (DDT). Among the various OCPs analyzed, p,p′-DDE was detected most frequently. All the contaminants recorded show higher accumulation in liver than other tissues. Levels of contaminants measured in the tissues of vulture are comparable with the levels documented in a number of avian species and are lower than those reported to have caused deleterious effects. Although no threat is expected from the current level of contamination, the presence of varying levels of contaminants and their additive or synergistic toxicity is a cause of concern to vultures. Values reported in this study can serve as guideline for future research. PMID:24288666

Exposure to organochlorine pesticides and non-Hodgkin lymphoma: a meta-analysis of observational studies

PubMed Central

Luo, Dan; Zhou, Tingting; Tao, Yun; Feng, Yaqian; Shen, Xiaoli; Mei, Surong

2016-01-01

Growing evidence indicates that exposure to organochlorine pesticides (OCPs) could increase non-Hodgkin lymphoma (NHL) risk. However, results from epidemiological studies investigating this association remain controversial. We thus conducted a meta-analysis to quantitatively evaluate the association between OCP exposure and NHL risk. Relevant publications were searched in PubMed, Web of Science, and Embase and identified according to the inclusion criteria. Thirteen studies (6 nested case-control, 1 case-cohort, and 6 case-control) were selected for this meta-analysis. We used odds ratios (ORs) with 95% confidence intervals (CIs) to estimate the relationship between OCPs exposure and NHL risk. The summary OR for included studies was 1.40 (95% CI 1.27 to 1.56). No overall significant heterogeneity in the OR was observed (Ph = 0.253, I2 = 12.6%). Furthermore, OR estimates in subgroup analyses were discussed, and strong associations were observed for dichlorodiphenyldichloroethylene (DDE, OR = 1.38, 95% CI 1.14 to 1.66), hexachlorocyclohexane (HCH, OR = 1.42, 95% CI 1.08 to 1.87), chlordane (OR = 1.93, 95% CI 1.51 to 2.48), and hexachlorobenzene (HCB, OR = 1.54, 95% CI 1.20 to 1.99). This meta-analysis had suggested that total OCPs of interest was significantly positively associated with NHL risk. PMID:27185567

Occurrences of Organochlorine Pesticides along the Course of the Buffalo River in the Eastern Cape of South Africa and Its Health Implications.

PubMed

Yahaya, Abdulrazaq; Okoh, Omobola O; Okoh, Anthony I; Adeniji, Abiodun O

2017-11-10

Most organochlorine pesticides (OCPs) which are increasingly used in agriculture and industry are not biodegradable and thereby persist in the environment for a very long period of time. They are capable of negatively impacting the health of humans and biota when present in a higher concentration than recommended. This study evaluated the concentrations of 17 OCPs in surface water samples collected from six sampling sites along the course of the Buffalo River in Eastern Cape, South Africa, between December 2015 and May 2016. The samples were subjected to solvent extraction, followed by florisil clean up, and analyzed using gas chromatography coupled with an electron capture detector. The individual concentrations of OCPs detected ranged from

Biomimetic fabrication of antibacterial calcium phosphates mediated by polydopamine.

PubMed

Forte, Lucia; Torricelli, Paola; Bonvicini, Francesca; Boanini, Elisa; Gentilomi, Giovanna Angela; Lusvardi, Gigliola; Della Bella, Elena; Fini, Milena; Vecchio Nepita, Edoardo; Bigi, Adriana

2018-01-01

In this work we developed new antibacterial composite materials using polydopamine (PDA) to trigger the deposition of silver nanoparticles (AgNPs) onto calcium phosphates, namely octacalcium phosphate (OCP) and α-tricalcium phosphate (αTCP). Functionalization of OCP and αTCP with a self-polymerized polydopamine layer was obtained by soaking the calcium phosphates in dopamine solution. The PDA surface of functionalized calcium phosphates (OCPd and αTCPd) promoted the deposition of AgNPs by reducing silver ions when soaked in a silver nitrate solution. The amount of deposited AgNPs can be modulated by varying the concentration of silver nitrate solution and the type of substrate. The results of in vitro tests carried out with osteoblast-like MG63 cells indicate that the combination of AgNPs with OCP provides more biocompatible materials than those obtained using αTCP as substrate. In particular, the study of osteoblast activity and differentiation was focused on the samples OCPdAg5 (silver content=8.2wt%) and αTCPdAg5 (silver content=4.7wt%), which did not show any cytotoxicity, and compared with those obtained on pure OCP and αTCP. The results demonstrate that the AgNPs loaded materials support osteoblast viability and differentiation, whereas they significantly inhibit the growth of relevant antibiotic-resistant pathogenic bacteria. Copyright © 2017 Elsevier Inc. All rights reserved.

Spatial trends, sources, and air-water exchange of organochlorine pesticides in the Great Lakes basin using low density polyethylene passive samplers.

PubMed

Khairy, Mohammed; Muir, Derek; Teixeira, Camilla; Lohmann, Rainer

2014-08-19

Polyethylene passive samplers were deployed during summer and fall of 2011 in the lower Great Lakes to assess the spatial distribution and sources of gaseous and freely dissolved organochlorine pesticides (OCPs) and their air-water exchange. Average gaseous OCP concentrations ranged from nondetect to 133 pg/m(3). Gaseous concentrations of hexachlorobenzene, dieldrin, and chlordanes were significantly greater (Mann-Whitney test, p < 0.05) at Lake Erie than Lake Ontario. A multiple linear regression implied that both cropland and urban areas within 50 and 10 km buffer zones, respectively, were critical parameters to explain the total variability in atmospheric concentrations. Freely dissolved OCP concentrations (nondetect to 114 pg/L) were lower than previously reported. Aqueous half-lives generally ranged from 1.7 to 6.7 years. Nonetheless, concentrations of p,p'-DDE and chlordanes were higher than New York State Ambient Water Quality Standards for the protection of human health from the consumption of fish. Spatial distributions of freely dissolved OCPs in both lakes were influenced by loadings from areas of concern and the water circulation patterns. Flux calculations indicated net deposition of γ-hexachlorocyclohexane, heptachlor-epoxide, and α- and β-endosulfan (-0.02 to -33 ng/m(2)/day) and net volatilization of heptachlor, aldrin, trans-chlordane, and trans-nonachlor (0.0 to 9.0 ng/m(2)/day) in most samples.

Flow microcapillary plasma mass spectrometry-based investigation of new Al-Cr-Fe complex metallic alloy passivation.

PubMed

Ott, N; Beni, A; Ulrich, A; Ludwig, C; Schmutz, P

2014-03-01

Al-Cr-Fe complex metallic alloys are new intermetallic phases with low surface energy, low friction, and high corrosion resistance down to very low pH values (0-2). Flow microcapillary plasma mass spectrometry under potentiostatic control was used to characterize the dynamic aspect of passivation of an Al-Cr-Fe gamma phase in acidic electrolytes, allowing a better insight on the parameters inducing chemical stability at the oxyhydroxide-solution interface. In sulfuric acid pH 0, low element dissolution rates (in the µg cm(-2) range after 60 min) evidenced the passive state of the Al-Cr-Fe gamma phase with a preferential over-stoichiometric dissolution of Al and Fe cations. Longer air-aging was found to be beneficial for stabilizing the passive film. In chloride-containing electrolytes, ten times higher Al dissolution rates were detected at open-circuit potential (OCP), indicating that the spontaneously formed passive film becomes unstable. However, electrochemical polarization at low passive potentials induces electrical field generated oxide film modification, increasing chemical stability at the oxyhydroxide-solution interface. In the high potential passive region, localized attack is initiated with subsequent active metal dissolution. © 2013 Published by Elsevier B.V.

Prepubertal Serum Concentrations of Organochlorine Pesticides and Age at Sexual Maturity in Russian Boys.

PubMed

Lam, Thuy; Williams, Paige L; Lee, Mary M; Korrick, Susan A; Birnbaum, Linda S; Burns, Jane S; Sergeyev, Oleg; Revich, Boris; Altshul, Larisa M; Patterson, Donald G; Hauser, Russ

2015-11-01

Few human studies have evaluated the impact of childhood exposure to organochlorine pesticides (OCP) on pubertal development. We evaluated associations of serum OCP concentrations [hexachlorobenzene (HCB), β-hexachlorocyclohexane (βHCH), and p,p-dichlorodiphenyldichloroethylene (p,p´-DDE)] with age at attainment of sexual maturity among boys. From 2003 through 2005, 350 8- to 9-year-old boys from Chapaevsk, Russia, with measured OCPs were enrolled and followed annually for 8 years. We used multivariable interval-censored models to evaluate associations of OCPs (quartiles) with three physician-assessed measures of sexual maturity: Tanner stage 5 for genitalia growth, Tanner stage 5 for pubic hair growth, or testicular volume (TV) ≥ 20 mL in either testis. In adjusted models, boys with higher HCB concentrations achieved sexual maturity reflected by TV ≥ 20 mL a mean of 3.1 months (95% CI: -1.7, 7.8), 5.3 months (95% CI: 0.6, 10.1), and 5.0 months (95% CI: 0.2, 9.8) later for quartiles Q2, Q3, and Q4, respectively, compared with Q1 (p trend = 0.04). Tanner stage 5 for genitalia growth was attained a mean of 2.2 months (95% CI: -3.1, 7.5), 5.7 months (95% CI: 0.4, 11.0), and 3.7 months (95% CI: -1.7, 9.1) later for quartiles Q2, Q3, and Q4, respectively, of βHCH compared with Q1 (p trend = 0.09). Tanner stage 5 for pubic hair growth occurred 6-9 months later on average for boys in the highest versus lowest quartile for HCB (p trend < 0.001), βHCH (trend p = 0.01), and p,p´-DDE (p trend = 0.04). No associations were observed between p,p´-DDE and Tanner stage 5 for genitalia growth or TV ≥ 20 mL. Higher prepubertal serum HCB and βHCH concentrations were associated with a later age at attainment of sexual maturity. Only the highest quartile of serum p,p´-DDE was associated with later pubic hair maturation. Lam T, Williams PL, Lee MM, Korrick SA, Birnbaum LS, Burns JS, Sergeyev O, Revich B, Altshul LM, Patterson DG Jr, Hauser R. 2015. Prepubertal serum concentrations of organochlorine pesticides and age at sexual maturity in Russian boys. Environ Health Perspect 123:1216-1221; http://dx.doi.org/10.1289/ehp.1409022.

Prepubertal Serum Concentrations of Organochlorine Pesticides and Age at Sexual Maturity in Russian Boys

PubMed Central

Lam, Thuy; Williams, Paige L.; Lee, Mary M.; Korrick, Susan A.; Birnbaum, Linda S.; Burns, Jane S.; Sergeyev, Oleg; Revich, Boris; Altshul, Larisa M.; Patterson, Donald G.

2015-01-01

Background Few human studies have evaluated the impact of childhood exposure to organochlorine pesticides (OCP) on pubertal development. Objective We evaluated associations of serum OCP concentrations [hexachlorobenzene (HCB), β-hexachlorocyclohexane (βHCH), and p,p-dichlorodiphenyldichloroethylene (p,p´-DDE)] with age at attainment of sexual maturity among boys. Methods From 2003 through 2005, 350 8- to 9-year-old boys from Chapaevsk, Russia, with measured OCPs were enrolled and followed annually for 8 years. We used multivariable interval-censored models to evaluate associations of OCPs (quartiles) with three physician-assessed measures of sexual maturity: Tanner stage 5 for genitalia growth, Tanner stage 5 for pubic hair growth, or testicular volume (TV) ≥ 20 mL in either testis. Results In adjusted models, boys with higher HCB concentrations achieved sexual maturity reflected by TV ≥ 20 mL a mean of 3.1 months (95% CI: –1.7, 7.8), 5.3 months (95% CI: 0.6, 10.1), and 5.0 months (95% CI: 0.2, 9.8) later for quartiles Q2, Q3, and Q4, respectively, compared with Q1 (p trend = 0.04). Tanner stage 5 for genitalia growth was attained a mean of 2.2 months (95% CI: –3.1, 7.5), 5.7 months (95% CI: 0.4, 11.0), and 3.7 months (95% CI: –1.7, 9.1) later for quartiles Q2, Q3, and Q4, respectively, of βHCH compared with Q1 (p trend = 0.09). Tanner stage 5 for pubic hair growth occurred 6–9 months later on average for boys in the highest versus lowest quartile for HCB (p trend < 0.001), βHCH (trend p = 0.01), and p,p´-DDE (p trend = 0.04). No associations were observed between p,p´-DDE and Tanner stage 5 for genitalia growth or TV ≥ 20 mL. Conclusions and relevance Higher prepubertal serum HCB and βHCH concentrations were associated with a later age at attainment of sexual maturity. Only the highest quartile of serum p,p´-DDE was associated with later pubic hair maturation. Citation Lam T, Williams PL, Lee MM, Korrick SA, Birnbaum LS, Burns JS, Sergeyev O, Revich B, Altshul LM, Patterson DG Jr, Hauser R. 2015. Prepubertal serum concentrations of organochlorine pesticides and age at sexual maturity in Russian boys. Environ Health Perspect 123:1216–1221; http://dx.doi.org/10.1289/ehp.1409022 PMID:26009253

The optimal SAM surface functional group for producing a biomimetic HA coating on Ti.

PubMed

Liu, D P; Majewski, P; O'Neill, B K; Ngothai, Y; Colby, C B

2006-06-15

Commercial interest is growing in biomimetic methods that employ self assembled mono-layers (SAMs) to produce biocompatible HA coatings on Ti-based orthopedic implants. Recently, separate studies have considered HA formation for various SAM surface functional groups. However, these have often neglected to verify crystallinity of the HA coating, which is essential for optimal bioactivity. Furthermore, differing experimental and analytical methods make performance comparisons difficult. This article investigates and evaluates HA formation for four of the most promising surface functional groups: --OH, --SO(3)H, --PO(4)H(2) and --COOH. All of them successfully formed a HA coating at Ca/P ratios between 1.49 and 1.62. However, only the --SO(3)H and --COOH end groups produced a predominantly crystalline HA. Furthermore, the --COOH end group yielded the thickest layer and possessed crystalline characteristics very similar to that of the human bone. The --COOH end group appears to provide the optimal SAM surface interface for nucleation and growth of biomimetic crystalline HA. Intriguingly, this finding may lend support to explanations elsewhere of why human bone sialoprotein is such a potent nucleator of HA and is attributed to the protein's glutamic acid-rich sequences.

Bone-like apatite layer formation on hydroxyapatite prepared by spark plasma sintering (SPS).

PubMed

Gu, Y W; Khor, K A; Cheang, P

2004-08-01

Hydroxyapatite (HA) compacts with high density and superior mechanical properties were fabricated by spark plasma sintering (SPS) using spray-dried HA powders as feedstock. The formation of bone-like apatite layer on SPS consolidated HA compacts were investigated by soaking the HA compacts in simulated body fluid (SBF) for various periods (maximum of 28 days). The structural changes in HA post-SBF were analyzed with scanning electron microscopy, grazing incidence X-ray diffraction and X-ray photoelectron spectroscopy. It was found that a layer consisting microcrystalline carbonate-containing hydroxyapatite was formed on the surface of HA compacts after soaking for 24h. The formation mechanism of apatite on the surface of HA compacts after soaking in SBF was attributed to the ion exchange between HA compacts and the SBF solution. The increase in ionic concentration of calcium and phosphorus as well as the increase in pH after SBF immersion resulted in an increase in ionic activity product of apatite in the solution, and provided a specific surface with a low interface energy that is conducive to the nucleation of apatite on the surface of HA compacts.

Potential public sector cost-savings from over-the-counter access to oral contraceptives.

PubMed

Foster, Diana G; Biggs, M Antonia; Phillips, Kathryn A; Grindlay, Kate; Grossman, Daniel

2015-05-01

This study estimates how making oral contraceptive pills (OCPs) available without a prescription may affect contraceptive use, unintended pregnancies and associated contraceptive and pregnancy costs among low-income women. Based on published figures, we estimate two scenarios [low over-the-counter (OTC) use and high OTC use] of the proportion of low-income women likely to switch to an OTC pill and predict adoption of OCPs according to the out-of-pocket costs per pill pack. We then estimate cost-savings of each scenario by comparing the total public sector cost of providing OCPs OTC and medical care for unintended pregnancy. Twenty-one percent of low-income women at risk for unintended pregnancy are very likely to use OCPs if they were available without a prescription. Women's use of OTC OCPs varies widely by the out-of-pocket pill pack cost. In a scenario assuming no out-of-pocket costs for the over-the counter pill, an additional 11-21% of low-income women will use the pill, resulting in a 20-36% decrease in the number of women using no method or a method less effective than the pill, and a 7-25% decrease in the number of unintended pregnancies, depending on the level of use and any effect on contraceptive failure rates. If out-of-pocket costs for such pills are low, OTC access could have a significant effect on use of effective contraceptives and unintended pregnancy. Public health plans may reduce expenditures on pregnancy and contraceptive healthcare services by covering oral contraceptives as an OTC product. Interest in OTC access to oral contraceptives is high. Removing the prescription barrier, particularly if pill packs are available at low or zero out-of-pocket cost, could increase the use of effective methods of contraception and reduce unintended pregnancy and healthcare costs for contraceptive and pregnancy care. Copyright © 2015 Elsevier Inc. All rights reserved.

Polycyclic aromatic hydrocarbons and organochlorine pesticides in rice hull from a typical e-waste recycling area in southeast China: temporal trend, source, and exposure assessment.

PubMed

Liu, Fang; Liao, Chunyang; Fu, Jianjie; Lv, Jungang; Xue, Qinzhao; Jiang, Guibin

2014-02-01

The residue levels of 16 US EPA priority polycyclic aromatic hydrocarbons (PAHs) and 16 selected organochlorine pesticides (OCPs) in rice and rice hull collected from a typical e-waste recycling area in southeast China were investigated from 2005 to 2007. PAHs and OCPs also were measured in ten mollusk species (soft tissues) collected in an adjacent bay in 2007. Individual PAHs were frequently found in the entire sample set (including the rice, hull, and mollusk samples) with a detection rate of 73 %. The total concentrations of 16 PAHs (ΣPAHs) and 16 OCPs (ΣOCPs) were in the range of 40.8-432 ng/g dry weight (mean: 171 ng/g) and 2.35-925 ng/g (122 ng/g), respectively, which were comparable or higher than those reported in some polluted areas. Statistical comparisons suggested that the concentrations of contaminants in hull gradually decreased from 2005 to 2007 and the residue levels were generally in the order of mollusk, hull, and rice, on a dry weight basis. Principal component analysis in combination with diagnostic ratios implied that combustion of coal, wood, and plastic wastes that are closely associated with crude e-waste recycling activities is the main source of PAHs. The finding of decreasing trend of concentrations of PAHs in this area is consistent with the efforts of local authorities to strengthen regulations on illegal e-waste recycling activities. Composition analysis suggested that there is a recent usage or discharge of hexachlorocyclohexane and dichlorodiphenyltrichloroethane into the tested area. The estimated daily intake (EDI) of ΣPAHs and ΣOCPs (calculated from mean concentrations) through rice and mollusk consumption was 0.411 and 0.921 μg/kg body weight (bw)/day, respectively.

Organochlorinated pesticides levels in a representative sample of the Spanish adult population: The Bioambient.es project.

PubMed

Ramos, Juan José; Huetos, Olga; González, Sara; Esteban, Marta; Calvo, Eva; Pérez-Gómez, Beatriz; Castaño, Argelia

2017-03-01

Organochlorinated pesticides (OCPs) were measured in a representative sample of Spanish adults within the Bioambient.es project, a nationwide human biomonitoring program promoted by Spanish Ministry of Agriculture, Food and Environment. The objective of Bioambient.es is to establish reference levels of environmental pollutants in the general population. Participants were recruited in 2009-2010 during their annual medical examination at work. Serum levels of thirteen OCPs were investigated: Aldrin, endrin, dieldrin, heptachlor, heptachlor-epoxide, dichlorodiphenyldichloroethylenes (DDEs), hexachlorobenzene (HCB), dichlorodiphenyltrichloroethanes (DDTs) and hexachlorocyclohexanes (HCHs) The highest concentrations were observed for DDE, HCB and β-HCH. The 95th percentile, in ng/g lipids, were: 717.7 for 4,4-DDE, 160.4 for HCB and 107.2 for β-HCH, while concentrations of aldrin, endrin, heptachlor, α-HCH, 2,4-DDT, 4,4-DDT and 2,4-DDE were markedly lower and detected in less than 10% of the samples. Significant differences (p<0.05) were found for DDE and HCB and seasonality, gender and age. Analyzing the geographical distribution, participants from the north of Spain had highest levels of HCB while those from the center of Spain had highest levels of 4,4-DDE. Comparing to earlier studies, the results indicated a sharp decline in the OCP concentrations in the Spanish population over time, and today values are in the same range or lower than those reported in similar studies worldwide, except for HCHs and HCB that presented higher levels than in other European countries and much higher than those observed in US and Canada. This study represents the first nationwide survey of exposure to OCPs in Spain and provides a background reference range for exposure to OCPs in the Spanish adult occupied population. These results will allow establishing reference values, observing temporal trends and identifying high exposure groups. Copyright © 2016 Elsevier GmbH. All rights reserved.

A Qualitative Study of Prescription Contraception Use: The Perspectives of Users, General Practitioners and Pharmacists

PubMed Central

Sweeney, Leigh-Ann; Molloy, Gerard J.; Byrne, Molly; Murphy, Andrew W.; Morgan, Karen; Hughes, Carmel M.; Ingham, Roger

2015-01-01

Background The oral contraceptive pill (OCP) remains the most popular form of prescription contraception in many countries, despite adherence difficulties for many. Uptake of long acting reversible contraceptives (LARCs), which are less reliant on user adherence, remains low. The aim of this study was to explore the experiences of, and attitudes towards, prescription contraception amongst samples of contraception users, general practitioners (GPs) and pharmacists. Methodology and Findings We conducted a qualitative study using semi-structured interviews with 18 contraception users, 18 GPs and 9 pharmacists. The study took place in Galway, Republic of Ireland between June and September 2014. Thematic analysis was used to analyse the data. Overall, contraception users were more familiar with the OCP, and all the women interviewed began their prescription contraception journey using this method. All participants identified episodes of poor adherence throughout the reproductive life course. The identified barriers for use of LARCs were lack of information, misconceptions, lack of access and high cost. In contrast, GPs believed that adherence to the OCP was good and stated they were more likely to prescribe the OCP than other methods, as they were most familiar with this option. Barriers to prescribing LARCSs were time, cost to practice, training and deskilling. Pharmacists also believed that adherence to the OCP was generally good and that their role was limited to dispensing medication and providing information when asked. Discussion and Conclusion There are contrasting perspectives between contraception service providers and contraceptive users. Training for healthcare providers is required to support informed contraceptive choice and adherence. It is necessary to address the practice barriers of cost and lack of time, to promote better communication around adherence issues and prescription contraception options. There is a need for more easily-accessible public health information to promote awareness on all methods of prescription contraception. PMID:26633191

XPS and bioactivity study of the bisphosphonate pamidronate adsorbed onto plasma sprayed hydroxyapatite coatings

NASA Astrophysics Data System (ADS)

McLeod, Kate; Kumar, Sunil; Smart, Roger St. C.; Dutta, Naba; Voelcker, Nicolas H.; Anderson, Gail I.; Sekel, Ron

2006-12-01

This paper reports the use of X-ray photoelectron spectroscopy (XPS) to investigate bisphosphonate (BP) adsorption onto plasma sprayed hydroxyapatite (HA) coatings commonly used for orthopaedic implants. BPs exhibit high binding affinity for the calcium present in HA and hence can be adsorbed onto HA-coated implants to exploit their beneficial properties for improved bone growth at the implant interface. A rigorous XPS analysis of pamidronate, a commonly used nitrogenous BP, adsorbed onto plasma sprayed HA-coated cobalt-chromium substrates has been carried out, aimed at: (a) confirming the adsorption of this BP onto HA; (b) studying the BP diffusion profile in the HA coating by employing the technique of XPS depth profiling; (c) confirming the bioactivity of the adsorbed BP. XPS spectra of plasma sprayed HA-coated discs exposed to a 10 mM aqueous BP solution (pamidronate) for periods of 1, 2 and 24 h showed nitrogen and phosphorous photoelectron signals corresponding to the BP, confirming its adsorption onto the HA substrate. XPS depth profiling of the 2 h BP-exposed HA discs showed penetration of the BP into the HA matrix to depths of at least 260 nm. The bioactivity of the adsorbed BP was confirmed by the observed inhibition of osteoclast (bone resorbing) cell activity. In comparison to the HA sample, the HA sample with adsorbed BP exhibited a 25-fold decrease in primary osteoclast cells.

Uranium and thorium complexes of the phosphaethynolate ion

DOE PAGES

Camp, Clément; Settineri, Nicholas; Lefèvre, Julia; ...

2015-06-20

New tris-amidinate actinide (Th, U) complexes containing a rare O-bound terminal phosphaethynolate (OCP⁻) ligand were synthesized and fully characterized. The cyanate (OCN⁻) and thiocyanate (SCN⁻) analogs were prepared for comparison and feature a preferential N-coordination to the actinide metals. The Th(amid) 3(OCP) complex reacts with Ni(COD) 2 to yield the heterobimetallic adduct (amid) 3Th(μ-η 1(O):η 2(C,P)-OCP)Ni(COD) featuring an unprecedented reduced (OCP⁻) bent fragment bridging the two metals.

Hyaluronic Acid Accelerates Tendon-to-Bone Healing After Rotator Cuff Repair.

PubMed

Honda, Hirokazu; Gotoh, Masafumi; Kanazawa, Tomonoshin; Ohzono, Hiroki; Nakamura, Hidehiro; Ohta, Keisuke; Nakamura, Kei-Ichiro; Fukuda, Kanji; Teramura, Takeshi; Hashimoto, Takashi; Shichijo, Shigeki; Shiba, Naoto

2017-12-01

There is growing evidence that the subacromial injection of hyaluronic acid (HA) is effective for pain relief in rotator cuff tears; however, its effect on tendon-to-bone healing remains unknown. To examine the effect of HA on the chondrogenesis of mesenchymal stem cells (MSCs) in vitro and on tendon-to-bone healing in a rotator cuff repair model. Controlled laboratory study. Bilateral complete tears of the infraspinatus tendon were made in rabbits and subsequently repaired. Before closure, 1 mL HA was applied to the repaired site, and phosphate-buffered saline was used in the opposite side as a control. Biomechanical, histological, and immunohistochemical analyses were performed at 4, 8, and 12 weeks after surgery. After euthanizing each animal, the bone marrow was isolated from the femoral bone in the same rabbits. Then, MSCs were cultured in media for chondrogenic differentiation, and the chondral pellet production and cartilage-related gene expression levels in the cells were examined at various concentrations of HA. At 4 and 8 weeks after surgery, ultimate load-to-failure was significantly greater in the HA group than in the control group (45.61 ± 9.0 N vs 32.42 ± 9.4 N at 4 weeks, 90.7 ± 16.0 N vs 66.97 ± 10.0 N at 8 weeks; both P < .05) but not at 12 weeks after surgery (109.6 ± 40.2 N vs 108.1 ± 42.6 N, P > .05). Linear stiffness was not significant throughout the time point evaluation. The chondroid formation area at the tendon-bone interface stained by safranin O (control vs HA group) was 0.33% ± 0.7% versus 13.5% ± 12.3% at 4 weeks after surgery ( P < .05) and 3.0% ± 5.9% versus 12.9% ± 12.9% at 8 weeks after surgery ( P < .05), but there was no significant difference at 12 weeks after surgery. Maturity of collagen at the repaired site stained by PicroSirius Red (control vs HA group) was 16.2 ± 10.6 versus 43.5 ± 21.3 at 4 weeks after surgery ( P < .05), but there were no significant differences at 8 and 12 weeks after surgery. MSCs were cultured in media for chondrogenic differentiation, and the chondral pellet production and cartilage-related gene expression levels in the cells were examined at various concentrations of HA. The number of CD44-positive cells (control vs HA group) was 8.3% ± 1.4% versus 26.2% ± 5.2% at 3 days after surgery ( P < .05), 1.8% ± 1.1% versus 26.6% ± 11.6% at 4 weeks after surgery ( P < .05), 0.6% ± 0.9% versus 0.5% ± 0.6% at 8 weeks after surgery ( P > .05), and 1.8% ± 4.0% versus 5.4% ± 4.2% at 12 weeks after surgery ( P > .05). Compared with the control group, HA significantly increased the volume of cartilaginous pellet produced by MSCs (0.0016 ± 0.0015 mm 3 at 0 mg/mL of HA, 0.0041 ± 0.0023 mm 3 at 1.0 mg/mL, and 0.0041 ± 0.0018 mm 3 at 4.0 mg/mL), with increased mRNA expression (relative ratio to control) of type 2 collagen (1.34 ± 0.38), SOX9 (1.58 ± 0.31), and aggrecan (1.30 ± 0.22) genes in the pellet ( P < .01). HA accelerated tendon-to-bone healing in the rotator cuff repair model, enhancing the biomechanical strength and increasing chondroid formation and tendon maturity at the tendon-bone interface. Based on the data of in vitro experiments, HA-activated MSCs may play a crucial role in the acceleration of tendon-to-bone healing. The data suggest the relevance of clinical application of HA to accelerate tendon-to-bone healing. It may decrease the number of retears after surgery.

Type-inversion as a working mechanism of high voltage MAPbBr3(Cl)-based halide perovskite solar cells.

PubMed

Kedem, Nir; Kulbak, Michael; Brenner, Thomas M; Hodes, Gary; Cahen, David

2017-02-22

Using several metals with different work functions as solar cell back contact we identify majority carrier type inversion in methylammonium lead bromide (MAPbBr3, without intentional doping) as the basis for the formation of a p-n junction. MAPbBr 3 films deposited on TiO 2 are slightly n-type, whereas in a full device they are strongly p-type. The charge transfer between the metal electrode and the halide perovskite (HaP) film is shown to determine the dominant charge carrier type of the HaP and, thus, also of the final cells. Usage of Pt, Au and Pb as metal electrodes shows the effects of metal work function on minority carrier diffusion length and majority carrier concentration in the HaP, as well as on built-in voltage, band bending, and open circuit voltage (V OC ) within a solar cell. V OC > 1.5 V is demonstrated. The higher the metal WF, the higher the carrier concentration induced in the HaP, as indicated by a narrower space charge region and a smaller minority carrier diffusion length. From the analysis of bias-dependent electron beam-induced currents, the HaP carrier concentrations are estimated to be ∼ 1 × 10 17 cm -3 with Au and 2-3 × 10 18 cm -3 with Pt. A model in which type-inversion stretches across the entire film width implies formation of the p-n junction away from the interface, near the back-contact metal electrode. This work highlights the importance of the contact metal on device performance in that contact engineering can also serve to control the carrier concentration in HaP.

Uptake of organochlorine pesticides by zucchini cultivars grown in polluted soils.

PubMed

Donnarumma, L; Pompi, V; Faraci, A; Conte, E

2008-01-01

Aim of this trial was to verify the occurrence and the distribution of organochlorine pesticides (OCPs) in zucchini cultivated varieties grown in glasshouses and in open field with different levels of pollutants in soil. Residues of OCPs have been detected in soils and crops in the province of Latina, an intensively agricultural area of Lazio Region, in Italy. The study has been focused at crop harvest in less contaminated glasshouses and during crop life cycle in contaminated field in spring-summer time. Dieldrin distribution in different part of plant is similar among zucchini cultivars grown in contaminated field. In crop grown in field and in glasshouses with soil pollution >0.01 mg/kg, we found dieldrin in all zucchini fruits and flowers, at the same level or higher than the maximum residue limit (RML) fixed by European law for edible vegetables (0.02 mg/kg). Instead in soil with pollution < or = 0.01 mg/kg total OCPs it would be possible to grow zucchini cultivars.

POP levels in blue crab (Callinectes sapidus) and edible fish from the eastern Mediterranean coast.

PubMed

Tekin, Serkan; Pazi, Idil

2017-01-01

Organochlorinated pesticides and Aroclors were measured in the muscle of two edible fish species (gray mullet, sea bream) and blue crab, collected from eastern Mediterranean coast in 2013. The concentration of organochlorinated pesticides (OCPs) and Aroclors in biota samples which were collected at six sites ranged from 1.0-8.6 and 9-47.5 ng g -1 wet weight, respectively. Total DDT concentrations in seafood samples were compared to tolerance level established by the US Food and Drug Administration (FDA); the concentrations were detected below the tolerence level. Health risk assessment was conducted related to the consumption of chemically contaminated seafood. The estimated daily intake of OCPs calculated by using the estimated daily fish consumption in Turkey was far below the acceptable daily intake as established by FAO/WHO. Our data indicated that consumption of blue crab, gray mullet, and sea bream collected from the Mediterranean coast of Turkey could pose "no risk" for human health in terms of OCPs.

[Influence of organochlorine pesticides in wastewater on the soil along the channel].

PubMed

Xu, Liang; Zhang, Cai-Xiang; Liu, Min; Liao, Xiao-Ping; Yao, Lin-Lin; Li, Jia-Le; Xiang, Qing-Qing

2013-08-01

Nine profile soil samples and two sewage water samples were collected from Xiaodian sewage irrigation area in Taiyuan city, concentrations of organochlorine pesticides (OCPs) were determined by the gas chromatography coupled with electron capture detector (GC-ECD) to analyze the influence of the leakage of sewage water. The result shows that OCPs in sewage water were mainly composed of HCHs. Concentrations of DDTs and other organochlorine pesticides were very low or out of the detection limit. Concentrations of sigmaOCPs and HCHs in eight profiles near irrigation channels to some extend decreased with the increasing of the linear distance off the channel, which shows influences of the leakage of sewage water on the soil nearby. Concentrations of HCHs clearly decreased with the increasing of soil depth in most profile soils. For the horizontal direction, concentrations of HCHs also decreased with the increasing of the linear distance off the channel. The correlation between HCHs and TOC was positive, but no correlation between pH and HCHs was found.

The relationship between alloying elements and biologically produced ennoblement in natural waters.

PubMed

Eashwar, M; Lakshman Kumar, A; Hariharasuthan, R; Sreedhar, G

2015-01-01

A range of stainless steels, nickel-chromium and nickel-chromium-molybdenum alloys were exposed to coastal seawater from Mandapam (Indian Ocean) and freshwater from a perennial pond. Biofilms from both test waters produced an ennoblement of the open circuit potential (OCP) on all alloys as expected, which was slower but substantially larger in freshwater. In both waters an interesting relationship was perceived between the plateau OCP (Emax) and the mass percentage of the major alloying elements. In particular, iron exhibited strong positive correlations with Emax (r(2) ≥ 0.77; p < 0.0005), while the sum of chromium, nickel and molybdenum presented significant negative correlations (r(2) ≤ -0.81; p = 0.0002). Consistent with the regression analyses, Euclidean distance clustering yielded patterns where Inconel-600 and the nickel-chromium-molybdenum alloys had the smallest similarities of OCP with other alloys. The results emphatically reinforce a key role for surface passive films in the ennoblement phenomenon in natural waters.

Participating in commercial space ventures: Introduction to NASA Centers for the Commercial Development of Space and the Cooperative Agreements Programs

NASA Technical Reports Server (NTRS)

1990-01-01

In response to a Presidential directive, NASA has implemented a space policy which actively supports and encourages U.S. industry investment and participation in commercial space ventures. NASA's Office of Commercial Programs (OCP) has played a significant role in stimulating the growth of commercial space activity. Through a variety of programs, OCP encourages commercial interest and involvement in space endeavors by providing access to NASA resources and opportunities for the emerging space industry to reduce the technical, financial, and business risks associated with space-related activities. This manual describes NASA's Commercial Uses of Space Program and introduces participants to four major OCP Commercial programs: Technology Utilization (TU), Small Business Innovation Research (SBIR), Centers for the Commercial Development of Space Flight Agreement (CCDSFA), and Cooperative Agreements Programs. The objective of this manual is to assist U.S. industry identify and pursue the appropriate agreement for participation in a commercial space venture.

A pill for HIV prevention: déjà vu all over again?

PubMed

Myers, Julie E; Sepkowitz, Kent A

2013-06-01

Recent FDA approval of tenofovir-emtricitabine for prevention of human immunodeficiency virus (HIV) as a form of pre-exposure prophylaxis (PrEP) has led to concern about implementation of this strategy. Fifty years ago, a very similar national and international debate occurred when the oral contraceptive pill ("the Pill" or "OCP") was approved. Contentious issues included OCP safety, cost, and the potential impact on sexual behavior--many of the same concerns being voiced currently about PrEP. In this article, we review the social and medical history of OCP, drawing parallels with the current PrEP debate. We also explore the key areas where PrEP differs from its forbear: lower efficacy, presence of drug resistance, and a more circumscribed (and marginalized) target population. A thoughtful approach to PrEP implementation, bearing in mind the historical insights gained from the 1960s, might serve as well as we begin this new chapter in the control of the HIV epidemic.

Development, validation and matrix effect of a QuEChERS method for the analysis of organochlorine pesticides in fish tissue.

PubMed

Stremel, Tatiana R De O; Domingues, Cinthia E; Zittel, Rosimara; Silva, Cleber P; Weinert, Patricia L; Monteiro, Franciele C; Campos, Sandro X

2018-04-03

This study aims to develop and validate a method to determine OCPs in fish tissues, minimizing the consumption of sample and reagents, by using a modified QuEChERS along with ultrasound, d-SPE and gas chromatography with an electron capture detector (GC-ECD), refraining the pooling. Different factorial designs were employed to optimize the sample preparation phase. The validation method presented a recovery of around 77.3% and 110.8%, with RSD lower than 13% and the detection limits were between 0.24 and 2.88 μgkg -1 , revealing good sensitiveness and accuracy. The method was satisfactorily applied to the analysis of tissues from different species of fish and OCPs residues were detected. The proposed method was shown effective to determine OCPs low concentrations in fish tissues, using small sample mass (0.5 g), making the sample analyses viable without the need for grouping (pool).

ANFIS multi criteria decision making for overseas construction projects: a methodology

NASA Astrophysics Data System (ADS)

Utama, W. P.; Chan, A. P. C.; Zulherman; Zahoor, H.; Gao, R.; Jumas, D. Y.

2018-02-01

A critical part when a company targeting a foreign market is how to make a better decision in connection with potential project selection. Since different attributes of information are often incomplete, imprecise and ill-defined in overseas projects selection, the process of decision making by relying on the experiences and intuition is a risky attitude. This paper aims to demonstrate a decision support method in deciding overseas construction projects (OCPs). An Adaptive Neuro-Fuzzy Inference System (ANFIS), the amalgamation of Neural Network and Fuzzy Theory, was used as decision support tool to decide to go or not go on OCPs. Root mean square error (RMSE) and coefficient of correlation (R) were employed to identify the ANFIS system indicating an optimum and efficient result. The optimum result was obtained from ANFIS network with two input membership functions, Gaussian membership function (gaussmf) and hybrid optimization method. The result shows that ANFIS may help the decision-making process for go/not go decision in OCPs.

Organochlorine Pesticides (OCPs) in Sediment and Fish of Two Tropical Water Bodies Under Different Land Use.

PubMed

Hinojosa-Garro, Demián; Burgos Chan, Adriana M; Rendón-von Osten, Jaime

2016-07-01

In this study we quantified and compared bioaccumulated OCPs in target fish species Cichlasoma urophthalmus (Mayan cichlid) and Oreochromis niloticus (Nile tilapia) and sediment in two lentic systems neighboring areas with different land use (Xnoha = agricultural/Mocu = nature reserve). Fish at both sites showed the same number of pesticide compounds (17) while in sediment were 17 and 20, respectively. ∑chlordane concentrations were significantly higher in Xnoha in both fish and sediment (1.0 and 0.17 µg/g, respectively). Here higher concentrations of o,p'DDT were found in fish than in sediments, this was similarly demonstrated in Mocu but to a lesser extent. The proportion of endosulfan sulfate was lower in Xnoha (<20 %) than in Mocu (<50 %) compared to the original product. Detected concentrations of ∑DDT and chlordane exceed international permissible limits. Results indicate that OCPs were present in both aquatic systems regardless of the differences in land use.

Organochlorine compounds and polycyclic aromatic hydrocarbons in surface sediment from Baiyangdian Lake, North China: concentrations, sources profiles and potential risk.

PubMed

Hu, Guocheng; Luo, Xiaojun; Li, Fengchao; Dai, Jiayin; Guo, Jianyang; Chen, Shejun; Hong, Cao; Mai, Bixian; Xu, Muqi

2010-01-01

Organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) were determined in nineteen surface sediment samples collected from Baiyangdian Lake and its inflowing river (Fuhe River) in North China. Total concentrations of OCPs, PCBs and PAHs in sediments ranged from 5.4 to 707.6 ng/g, 2.3 to 197.8 ng/g, and 101.3 to 6360.5 ng/g, respectively. The levels of contaminants in Fuhe River were significantly higher than those in Baiyandian Lake. For hexachlorocyclohexane (HCHs) and dichlorodiphenytrichloroethanes (DDTs), alpha-HCH and p,p'-DDT were predominant isomers; while for PCBs, PCB 28/31, PCB 40/103, PCB 60, PCB 101, and PCB 118 were predominant congeners. Possible sources derived from historical usage for OCPs and incomplete combustion fuel, wood, and coal and exhaustion of boats or cars for PAHs. Risk assessment of sediment indicated that sediments in Fuhe River were likely to pose potential biological adverse impact.

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in sediments from an urban- and industrial-impacted subtropical estuary (Babitonga Bay, Brazil).

PubMed

Rizzi, Juliane; Taniguchi, Satie; Martins, César C

2017-06-15

Babitonga Bay is a large estuary, which has been under pressure from anthropogenic activities coexisting with a natural area of Atlantic rainforest and mangrove systems. The concentration of persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) was determined to evaluate the contamination status and the determine possible pollution sources in the estuary. The ∑DDT (sum of DDT, DDE and DDD concentrations) was the predominant OCP group, with concentrations ranging from

Pedicle screws with a thin hydroxyapatite coating for improving fixation at the bone-implant interface in the osteoporotic spine: experimental study in a porcine model.

PubMed

Ohe, Makoto; Moridaira, Hiroshi; Inami, Satoshi; Takeuchi, Daisaku; Nohara, Yutaka; Taneichi, Hiroshi

2018-03-30

OBJECTIVE Instrumentation failure caused by the loosening of pedicle screws (PSs) in patients with osteoporosis is a serious problem after spinal surgery. The addition of a thin hydroxyapatite (HA) surface coating applied by using a sputtering process was reported recently to be a promising method for providing bone conduction around an implant without a significant risk of coating-layer breakage. In this study, the authors evaluated the biomechanical and histological features of the bone-implant interface (BII) of PSs with a thin HA coating in an in vivo porcine osteoporotic spine model. METHODS Three types of PSs (untreated/standard [STPS], sandblasted [BLPS], and HA-coated [HAPS] PSs) were implanted into the thoracic and lumbar spine (T9-L6) of 8 mature Clawn miniature pigs (6 ovariectomized [osteoporosis group] and 2 sham-operated [control group] pigs). The spines were harvested from the osteoporosis group at 0, 2, 4, 8, 12, or 24 weeks after PS placement and from the control group at 0 or 24 weeks. Their bone mineral density (BMD) was measured by peripheral quantitative CT. Histological evaluation of the BIIs was conducted by performing bone volume/tissue volume and bone surface/implant surface measurements. The strength of the BII was evaluated with extraction torque testing. RESULTS The BMD decreased significantly in the osteoporosis group (p < 0.01). HAPSs exhibited the greatest mean extraction peak torque at 8 weeks, and HAPSs and BLPSs exhibited significantly greater mean torque than the STPSs at 12 weeks (p < 0.05). The bone surface/implant surface ratio was significantly higher for HAPSs than for STPSs after 2 weeks (p < 0.05), and bonding between bone and the implant surface was maintained until 24 weeks with no detachment of the coating layer. In contrast, the bone volume/tissue volume ratio was significantly higher for HAPSs than for BLPSs or STPSs only at 4 weeks. CONCLUSIONS Using PSs with a thin HA coating applied using a sputtering process strengthens bonding at the BII, which might improve early implant fixation after spinal surgery for osteoporosis. However, the absence of increased bone mass around the screw remains a concern; prescribing osteoporosis treatment to improve bone quality might be necessary to prevent fractures around the screws.

3D Printing Surgical Implants at the clinic: A Experimental Study on Anterior Cruciate Ligament Reconstruction

PubMed Central

Liu, An; Xue, Guang-huai; Sun, Miao; Shao, Hui-feng; Ma, Chi-yuan; Gao, Qing; Gou, Zhong-ru; Yan, Shi-gui; Liu, Yan-ming; He, Yong

2016-01-01

Desktop three-dimensional (3D) printers (D3DPs) have become a popular tool for fabricating personalized consumer products, favored for low cost, easy operation, and other advantageous qualities. This study focused on the potential for using D3DPs to successfully, rapidly, and economically print customized implants at medical clinics. An experiment was conducted on a D3DP-printed anterior cruciate ligament surgical implant using a rabbit model. A well-defined, orthogonal, porous PLA screw-like scaffold was printed, then coated with hydroxyapatite (HA) to improve its osteoconductivity. As an internal fixation as well as an ideal cell delivery system, the osteogenic scaffold loaded with mesenchymal stem cells (MSCs) were evaluated through both in vitro and in vivo tests to observe bone-ligament healing via cell therapy. The MSCs suspended in Pluronic F-127 hydrogel on PLA/HA screw-like scaffold showed the highest cell proliferation and osteogenesis in vitro. In vivo assessment of rabbit anterior cruciate ligament models for 4 and 12 weeks showed that the PLA/HA screw-like scaffold loaded with MSCs suspended in Pluronic F-127 hydrogel exhibited significant bone ingrowth and bone-graft interface formation within the bone tunnel. Overall, the results of this study demonstrate that fabricating surgical implants at the clinic (fab@clinic) with D3DPs can be feasible, effective, and economical. PMID:26875826

Global Picosecond Structural Dynamics of Orange Carotenoid Protein in Photo/Chemical Activated Signaling States

NASA Astrophysics Data System (ADS)

Deng, Yanting; Xu, Mengyang; Liu, Hanjun; Blankenship, Robert; Markelz, Andrea

Light availability to photosynthetic organisms changes throughout the day. High light can over-saturate photosynthetic capacity and produce reactive oxygen which damages the photosynthetic apparatus and leads to cell death. Photosynthetic organisms have evolved multiple photo-protective strategies to prevent oxidative damage from light stress. For cyanobacteria, a blue-light photo-sensor orange carotenoid protein (OCP) responds to exposure to intense light. Upon high light stress, OCP converts from the orange inactive form (OCPO) to the red active form (OCPR) , with a large conformational change. And OCPR interacts with the light harvesting antenna phycobilisome (PB), and mediates the energy quenching of PB. We argue that both the susceptibility of OCP to large conformational change and its interaction with PB are associated with changes in the long range picosecond structural flexibility. To investigate the protein flexibility with signaling state dependence, temperature dependent terahertz time domain spectroscopy is performed in the range of 80 - 290 K on OCP solutions, as a function of illumination and chaotrope (NaSCN) concentration, which produces a long lived red state in the absence of photoexcitation. We characterize the global flexibility by both the net THz absorbance and the dynamical transition temperature, which scales with structural stability, and observed the dynamical transition occurred in the 180-220 K range. R.E.B. acknowledges DOE award DE-FG02- 07ER15902 and A.G.M. acknowledges NSF awards DBI 1556359 and MCB 1616529, and DOE award DE-SC0016317 for support of the work.

DDTs and HCHs in sediment cores from the coastal East China Sea.

PubMed

Lin, Tian; Nizzetto, Luca; Guo, Zhigang; Li, Yuanyuan; Li, Jun; Zhang, Gan

2016-01-01

Four sediment cores were collected along the Yangtze-derived sediment transport pathway in the inner shelf of the East China Sea (ECS) for OCP analysis. The sediment records of HCHs and DDTs in estuarine environment reflected remobilization of chemicals from enhanced soil erosion associated to extreme flood events or large scale land use transformation. The sediment records in the open sea, instead, reflected long-term historical trends of OCP application in the source region. Unlike the so-called mud wedge distribution of sediment, inventories of HCHs and DDTs slightly increased from the mouth of Yangtze River alongshore toward south, suggesting the sediment deposition rate was one of factors on the exposure of chemicals within the inner shelf of the ECS. Re-suspension and transport of the Yangtze-derived sediment and consequent fractionation in grain size and TOC were also responsible for the spatial variation of inventories of catchment derived OCPs in a major repository area of the Yangtze suspended sediment. The total burdens of HCHs and DDTs in the inner shelf of the ECS were 35tons and 110tons, respectively. After 1983 (year of the official ban in China), those values were 13tons and 50tons, respectively. It appears that the Yangtze still delivers relatively high inputs of DDTs more than 30years after the official ban. High proportions of DDD+DDE and β-HCH suggested those OCPs mainly originated from historical usage in the catchment recent years. Copyright © 2015 Elsevier B.V. All rights reserved.

Is the suppressive effect of cyproterone acetate on serum anti-Müllerian-hormone levels in women with polycystic ovary syndrome stronger than under oral contraceptive pill?

PubMed

Plouvier, Pauline; Peigné, Maëliss; Gronier, Héloïse; Robin, Geoffroy; Catteau-Jonard, Sophie; Dewailly, Didier

2016-08-01

To compare the suppressive effect of anti-androgen therapy by cyproterone acetate (CPA) and by oral contraceptive pill (OCP) on anti-müllerian hormone (AMH) levels in women with polycystic ovary syndrome (PCOS) in order to detect a putative direct anti-androgen effect on AMH excess. This is a prospective longitudinal study including 58 women with PCOS between January 2010 and April 2014 at the Lille University Hospital. A total of 47 women with clinical hyperandrogenism were treated by CPA (50 mg/d was administered 20 days out of 28) and 11 women with PCOS but without clinical hyperandrogenism received OCP. Serum AHM levels at baseline were similar in CPA and OCP groups (median [5-95th percentiles]: 60.4 pmol/l [25.1-200.2] versus 58 pmol/l [27.6-100], respectively, p = 0.39). After 3 months of treatment, serum AMH levels decreased significantly by 28% ± 20% and by 22% ± 27% in CPA and OCP groups, respectively. The decrease under both treatments was similar (p = 0.48). That any anti-androgen effect could be observed on AMH in our CPA group in addition to the gonadotropin-suppressing effect suggests that either androgens are not involved in AMH regulation or that they act by interfering with gonadotropin effects on granulosa cells.

Current status and historical trends of organochlorine pesticides in the ecosystem of Deep Bay, South China

NASA Astrophysics Data System (ADS)

Qiu, Yao-Wen; Zhang, Gan; Guo, Ling-Li; Cheng, Hai-Rong; Wang, Wen-Xiong; Li, Xiang-Dong; Wai, Onyx W. H.

2009-11-01

To characterize the current status and historical trends in organochlorine pesticides (OCPs) contamination in Deep Bay, an important water body between Hong Kong and mainland China with a Ramsar mangrove wetland (Maipo), samples from seawater, suspended particulate matter (SPM), surface sediment, sediment core and fish were collected to determine the OCPs concentrations. Sediment core dating was accomplished using the 210Pb method. The average concentrations of DDTs, HCHs and chlordanes in water were 1.96, 0.71, 0.81 ng l -1, while in SPM were 36.5, 2.5, 35.7 ng g -1 dry weight, in surface sediment were 20.2, 0.50, 2.4 ng g -1 dry weight, and in fish were 125.4, 0.43, 13.1 ng g -1 wet weight, respectively. DDTs concentrations in various matrices of Deep Bay were intermediate compared with those in other areas. Temporal trends of the targeted OCPs levels in sediment core generally increased from 1948 to 2004, with the highest levels in top or sub-surface sediment. Both DDT composition and historical trends indicated an ongoing fresh DDT input. A positive relationship between the bioconcentration factor (BCF) of target chemicals and the corresponding octanol-water partition coefficient ( Kow), and between the biota-sediment accumulation factors (BSAF) and the Kow were observed in the Bay. The risk assessment indicated that there were potential ecological and human health risks for the target OCPs in Deep Bay.

Paralogs of the C-Terminal Domain of the Cyanobacterial Orange Carotenoid Protein Are Carotenoid Donors to Helical Carotenoid Proteins1[OPEN

PubMed Central

Muzzopappa, Fernando; Wilson, Adjélé; Yogarajah, Vinosa; Cot, Sandrine; Perreau, François; Montigny, Cédric; Bourcier de Carbon, Céline

2017-01-01

The photoactive Orange Carotenoid Protein (OCP) photoprotects cyanobacteria cells by quenching singlet oxygen and excess excitation energy. Its N-terminal domain is the active part of the protein, and the C-terminal domain regulates the activity. Recently, the characteristics of a family of soluble carotenoid-binding proteins (Helical Carotenoid Proteins [HCPs]), paralogs of the N-terminal domain of OCP, were described. Bioinformatics studies also revealed the existence of genes coding for homologs of CTD. Here, we show that the latter genes encode carotenoid proteins (CTDHs). This family of proteins contains two subgroups with distinct characteristics. One CTDH of each clade was further characterized, and they proved to be very good singlet oxygen quenchers. When synthesized in Escherichia coli or Synechocystis PCC 6803, CTDHs formed dimers that share a carotenoid molecule and are able to transfer their carotenoid to apo-HCPs and apo-OCP. The CTDHs from clade 2 have a cysteine in position 103. A disulfide bond is easily formed between the monomers of the dimer preventing carotenoid transfer. This suggests that the transfer of the carotenoid could be redox regulated in clade 2 CTDH. We also demonstrate here that apo-OCPs and apo-CTDHs are able to take the carotenoid directly from membranes, while HCPs are unable to do so. HCPs need the presence of CTDH to become holo-proteins. We propose that, in cyanobacteria, the CTDHs are carotenoid donors to HCPs. PMID:28935842

Quantum molecular dynamics study on the proton exchange, ionic structures, and transport properties of warm dense hydrogen-deuterium mixtures

NASA Astrophysics Data System (ADS)

Liu, Lei; Li, Zhi-Guo; Dai, Jia-Yu; Chen, Qi-Feng; Chen, Xiang-Rong

2018-06-01

Comprehensive knowledge of physical properties such as equation of state (EOS), proton exchange, dynamic structures, diffusion coefficients, and viscosities of hydrogen-deuterium mixtures with densities from 0.1 to 5 g /cm3 and temperatures from 1 to 50 kK has been presented via quantum molecular dynamics (QMD) simulations. The existing multi-shock experimental EOS provides an important benchmark to evaluate exchange-correlation functionals. The comparison of simulations with experiments indicates that a nonlocal van der Waals density functional (vdW-DF1) produces excellent results. Fraction analysis of molecules using a weighted integral over pair distribution functions was performed. A dissociation diagram together with a boundary where the proton exchange (H2+D2⇌2 HD ) occurs was generated, which shows evidence that the HD molecules form as the H2 and D2 molecules are almost 50% dissociated. The mechanism of proton exchange can be interpreted as a process of dissociation followed by recombination. The ionic structures at extreme conditions were analyzed by the effective coordination number model. High-order cluster, circle, and chain structures can be founded in the strongly coupled warm dense regime. The present QMD diffusion coefficient and viscosity can be used to benchmark two analytical one-component plasma (OCP) models: the Coulomb and Yukawa OCP models.

Brominated Flame Retardants and Other Persistent Organohalogenated Compounds in Relation to Timing of Puberty in a Longitudinal Study of Girls.

PubMed

Windham, Gayle C; Pinney, Susan M; Voss, Robert W; Sjödin, Andreas; Biro, Frank M; Greenspan, Louise C; Stewart, Susan; Hiatt, Robert A; Kushi, Lawrence H

2015-10-01

Exposure to hormonally active chemicals could plausibly affect pubertal timing, so we are investigating this in the Breast Cancer and the Environment Research Program. Our goal was to examine persistent organic pollutants (POPs) in relation to pubertal onset. Ethnically diverse cohorts of 6- to 8-year-old girls (n = 645) provided serum for measure of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and lipids. Tanner stages [breast (B) and pubic hair (PH)], and body mass index (BMI) were measured at up to seven annual clinic visits. Using accelerated failure time models, we calculated time ratios (TRs) for age at Tanner stages 2 or higher (2+) and POPs quartiles (Q1-4), adjusting for confounders (race/ethnicity, site, caregiver education, and income). We also calculated prevalence ratios (PRs) of Tanner stages 2+ at time of blood sampling. Cross-sectionally, the prevalence of B2+ and PH2+ was inversely related to chemical serum concentrations; but after adjustment for confounders, only the associations with B2+, not PH2+, were statistically significant. Longitudinally, the age at pubertal transition was consistently older with greater chemical concentrations; for example: adjusted TR for B2+ and Q4 for ΣPBDE = 1.05; 95% CI: 1.02, 1.08, for ΣPCB = 1.05; 95% CI: 1.01, 1.08, and for ΣOCP = 1.10; 95% CI: 1.06, 1.14, indicating median ages of about 6 and 11 months older than least exposed, and with similar effect estimates for PH2+. Adjusting for BMI attenuated associations for PCBs and OCPs but not for PBDEs. This first longitudinal study of puberty in girls with serum POPs measurements (to our knowledge) reveals a delay in onset with higher concentrations.

Comninou contact zones for a crack parallel to an interface

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joseph, P.F.; Gadi, K.S.; Erdogen, F.

One of the interesting features in studying the state of stress in elastic solids near singular points, is the so called complex singularity that gives rise to an apparent local oscillatory behavior in the stress and displacement fields. The region in which this occurs is very small, much smaller than any plastic zone would be, and therefore the oscillations can be ignored in practical applications. Nevertheless, it is a matter of interesting theoretical investigation. The Comninou model of a small contact zone near the crack tip appears to correct for this anomaly within the framework of the linear theory. Thismore » model seems to make sense out of a {open_quotes}solution{close_quotes} that violates the boundary conditions. Erdogan and Joseph, showed (to themselves anyway) that the Comninou model actually has a physical basis. They considered a crack parallel to an interface where the order of the singularity is always real. With great care in solving the singular integral equations, it was shown that as the crack approaches the interface, a pinching effect is observed at the crack tip. This pinching effect proves that in the limit as the crack approaches the interface, the correct way to handle the problem is to consider crack surface contact. In this way, the issue of {open_quotes}oscillations{close_quotes} is never encountered for the interface crack problem. In the present study, the value of h/a that corresponds to crack closure (zero value of the stress intensity factor) will be determined for a given material pair for tensile loading. An asymptotic numerical method for the solution of singular integral equations making use of is used to obtain this result. Results for the crack opening displacement near the tip of the crack and the behavior of the stress intensity factor for cracks very close to the interface are presented. Among other interesting issues to be discussed, this solution shows that the semi-infinite crack parallel to an interface is closed.« less

MOBILE-izing Adolescent Sexual and Reproductive Health Care: A Pilot Study Using a Mobile Health Unit in Chicago.

PubMed

Stefansson, Lilja S; Webb, M Elizabeth; Hebert, Luciana E; Masinter, Lisa; Gilliam, Melissa L

2018-03-01

Adolescents experience numerous barriers to obtaining sexual and reproductive health care (SRHC). Mobile Health Units (MHUs) can remove some barriers by traveling to the community. This pilot study developed Mobile SRHC through an iterative process on an existing MHU and evaluated it among adolescents and providers. Mobile SRHC was developed through a mixed-method, multiphase study. Three key informant interviews with MHU providers, an adolescent needs assessment survey, and a Youth Model Development Session informed model development. Emergency contraception (EC), oral contraceptive pills (OCPs), and depot-medroxyprogesterone acetate (DMPA) were sequentially incorporated into MHU services. Administrative data assessed method distribution and surveys assessed patient satisfaction. Key informants held positive attitudes toward implementing Mobile SRHC into their practice. Needs assessment surveys (N = 103) indicated a majority was interested in learning about sexual health (66.0%) and obtaining birth control (54.4%) on an MHU. Over 3 months, 123 adolescents participated in Mobile SRHC. Seven packs and 9 prescriptions of EC, 8 3-month packs and 10 prescriptions of OCPs, and 5 injections and 5 prescriptions of DMPA were distributed. Ninety-two percent of adolescent participants reported they would recommend Mobile SRHC to friends. Mobile SRHC is a feasible approach for reproductive health care among adolescents. © 2018, American School Health Association.

Effect of humic acid preloading on phosphate adsorption onto zirconium-modified zeolite.

PubMed

Lin, Jianwei; Zhang, Zhe; Zhan, Yanhui

2017-05-01

A zirconium-modified zeolite (ZrMZ) was prepared, and then, humic acid (HA) was immobilized on the ZrMZ surface to prepare HA-loaded ZrMZ (HA-ZrMZ). The obtained ZrMZ and HA-ZrMZ were characterized by energy dispersive X-ray spectroscopy, elemental analyzer, N 2 adsorption/desorption isotherms, pH at the point of zero charge, and X-ray photoelectron spectroscopy. The adsorption characteristics of phosphate on ZrMZ and HA-ZrMZ were comparatively investigated in batch mode. The adsorption mechanism of phosphate on ZrMZ and HA-ZrMZ was investigated by ionic strength effect and 31 P nuclear magnetic resonance. The mechanism for phosphate adsorption onto ZrMZ was the formation of inner-sphere phosphate complexes at the solid/solution interface. The preloading of HA on ZrMZ reduced the phosphate adsorption capacity, and the more the HA loading amount, the lower the phosphate adsorption capacity. However, the preloading of HA on ZrMZ did not change the phosphate adsorption mechanism; i.e., the formation of inner-sphere phosphate surface complexes was still responsible for the adsorption of phosphate on HA-ZrMZ. The decreased phosphate adsorption capacity for ZrMZ after HA coating could be attributed to the fact that the coating of HA on ZrMZ reduced the amount of binding active sites available for phosphate adsorption, changed the adsorbent surface charges, and reduced the specific surface areas and pore volumes of ZrMZ.

Evaluation of pesticide residues of organochlorine in vegetables and fruits in Qatar: statistical analysis.

PubMed

Al-Shamary, Noora M; Al-Ghouti, Mohammad A; Al-Shaikh, Ismail; Al-Meer, Saeed H; Ahmad, Talaat A

2016-03-01

The study aimed to examine the residues of organochlorines pesticides (OCPs) in vegetables and fruits in Qatar. A total of 127 samples was studied. Ninety percent of the imported samples recorded residues above the maximum residue levels (MRLs). The most frequently detected OCP in the samples was heptachlor (found in 75 samples). In the comparisons between the washed and unwashed samples, no significant differences were observed (P > 0.05). However, the effect of washing process with tap water depended on the type of vegetables and fruits.

Microstructural inhomogeneity in plasma-sprayed hydroxyapatite coatings and effect of post-heat treatment

NASA Astrophysics Data System (ADS)

Lu, Yu-Peng; Xiao, Gui-Yong; Li, Shi-Tong; Sun, Rui-Xue; Li, Mu-Sen

2006-01-01

The microstructural inhomogeneity in the plasma-sprayed hydroxyapatite (HA) coatings was characterized by using electron probe microanalyser (EPMA). A simple and artful method was developed to detect the interface characteristics. All the samples for observation were ground and polished along the direction parallel to the coating surfaces. The BSE images directly and clearly showed the inhomogeneity in the as-sprayed coatings with the amorphous regions being bright gray and crystalline regions being dark gray. X-ray diffractometer (XRD) patterns indicated that after immersion in deionized water for 20 days, bone-like apatite and α-Ca 2P 2O 7 precipitated on the polished surfaces of the as-sprayed HA coatings. The post-heat treatment could eliminate the microstructural inhomogeneity in the coatings. Only β-Ca 2P 2O 7 precipitated on the surfaces of the heat-treated HA coatings. The immersed samples were re-polished till tiny substrate was bared to investigate the effect of immersion on interface. It was shown that the immersion decreased the cohesive strength of the as-sprayed coatings. There were more and broader cracks in the splats that came into contact with the substrate and amorphous phase increased toward the coating-substrate interface. Post-heat treatment was proved to reduce the peeling off of coating during re-polishing operation. It was proposed that the distributions of amorphous phase and cracks in as-sprayed coatings are detrimental to coating properties and should be modified through improving the plasma spraying processing.

Hydroxyapatite coatings produced on commercially pure titanium by micro-arc oxidation.

PubMed

Huang, Yong; Wang, Yingjun; Ning, Chengyun; Nan, Kaihui; Han, Yong

2007-09-01

A porous hydroxyapatite (HA) coating on commercially pure titanium was prepared by micro-arc oxidation (MAO) in electrolytic solution containing calcium acetate and beta-glycerol phosphate disodium salt pentahydrate (beta-GP). The thickness, phase, composition morphology and biocompatibility of the oxide coating were characterized by x-ray diffraction (XRD), electron probe microanalysis (EPMA), scanning electron microscopy (SEM) with an energy dispersive x-ray spectrometer (EDS) and cell culture. The thickness of the MAO film was about 20 microm, and the coating was porous and uneven without any apparent interface to the titanium substrates. The result of XRD showed that the porous coating was made up of HA film. The favorable osteoblast cell affinity gives HA film good biocompatibility. HA coatings are expected to have significant uses for medical applications such as dental implants and artificial bone joints.

Hierarchical Structure and Mechanical Improvement of an n-HA/GCO-PU Composite Scaffold for Bone Regeneration.

PubMed

Li, Limei; Zuo, Yi; Zou, Qin; Yang, Boyuan; Lin, Lili; Li, Jidong; Li, Yubao

2015-10-14

To improve the mechanical properties of bone tissue and achieve the desired bone tissue regeneration for orthopedic surgery, newly designed hydroxyapatite/polyurethane (HA/PU) porous scaffolds were developed via in situ polymerization. The results showed that the molecular modification of PU soft segments by glyceride of castor oil (GCO) can increase the scaffold compressive strength by 48% and the elastic modulus by 96%. When nano-HA (n-HA) particles were incorporated into the GCO-PU matrix, the compressive strength and elastic modulus further increased by 49 and 74%, from 2.91 to 4.34 MPa and from 95 to 165.36 MPa, respectively. The n-HA particles with fine dispersity not only improved the interface bonding with the GCO-PU matrix but also provided effective bioactivity for bonding with bone tissue. The hierarchical structure and mechanical quality of the n-HA/GCO-PU composite scaffold were determined to be appropriate for the growth of cells and the regeneration of bony tissues, demonstrating promising prospects for bone repair and regeneration.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takeshita, Takayuki; Okamoto, Masami

The hydroxyapatite (HA) formation on the surface of DNA molecules in simulated body fluid (SBF) was examined. The osteoconductivity is estimated using SBF having ion concentrations approximately equal to those of human blood plasma. After immersion for 4 weeks in SBF at 36.5 °C, the HA crystallites possessing 1-14 micrometer in diameter grew on the surface of DNA molecules. The leaf flake-like and spherical shapes morphologies were observed through scanning electron microscopy analysis. Original peaks of both of DNA and HA were characterized by fourier transform infrared spectroscopy. The Ca/P ratio (1.1-1.5) in HA was estimated by energy dispersive X-raymore » analysis. After biomineralization, the calculated weight ratio of DNA/HA was 18/82 by thermogravimetry/differential thermal analysis. The molecular orbital computer simulation has been used to probe the interaction of DNA with two charge-balancing ions, CaOH{sup +} and CaH{sub 2}PO{sub 4}{sup +}. The adsorption enthalpy of the two ions on DNA having negative value was the evidence for the interface in mineralization of HA in SBF.« less

Fabrication of DNA/Hydroxyapatite nanocomposites by simulated body fluid for gene delivery

NASA Astrophysics Data System (ADS)

Takeshita, Takayuki; Okamoto, Masami

2015-05-01

The hydroxyapatite (HA) formation on the surface of DNA molecules in simulated body fluid (SBF) was examined. The osteoconductivity is estimated using SBF having ion concentrations approximately equal to those of human blood plasma. After immersion for 4 weeks in SBF at 36.5 °C, the HA crystallites possessing 1-14 micrometer in diameter grew on the surface of DNA molecules. The leaf flake-like and spherical shapes morphologies were observed through scanning electron microscopy analysis. Original peaks of both of DNA and HA were characterized by fourier transform infrared spectroscopy. The Ca/P ratio (1.1-1.5) in HA was estimated by energy dispersive X-ray analysis. After biomineralization, the calculated weight ratio of DNA/HA was 18/82 by thermogravimetry/differential thermal analysis. The molecular orbital computer simulation has been used to probe the interaction of DNA with two charge-balancing ions, CaOH+ and C a H2P O4+ . The adsorption enthalpy of the two ions on DNA having negative value was the evidence for the interface in mineralization of HA in SBF.

The influence of silanisation on the mechanical and degradation behaviour of PLGA/HA composites.

PubMed

Naik, Ashutosh; Best, Serena M; Cameron, Ruth E

2015-03-01

This study investigates the influence of silanisation on the mechanical and degradation behaviour of PLGA/HA composites. Three different silanes (mercaptopropyl trimethoxy silane (MPTMS), aminopropyl trimethoxy silane (APTMS) and aminopropyltriethoxy silane (APTES)) were applied to HA substrates in order to study the effect of head group (which binds to the polymer) and tail group (which binds to the surface hydroxyl groups in HA). A composite of hydroxyapatite (HA) and poly(d,l lactide-co-glycolide (50:50)) (PLGA) was investigated. The influence of concentration, the reaction time, drying temperature and substrate surface on silanisation was examined. TGA was used to detect the degree of silanisation. HA with MPTMS (1wt.% MPTMS with reaction time of 1h) was used as filler in PLGA-30wt.% HA composites for an in-vitro degradation study carried out in PBS. In addition, the mechanical properties of the composites were studied. Silanisation affects the properties of the composite by improving the bonding at the interface and hence it was found to influence the plastic mechanical properties rather than the elastic mechanical properties or the degradation profile of the composite. Copyright © 2014. Published by Elsevier B.V.

Poly-L-lysine/hydroxyapatite/carbon nanotube hybrid nanocomposite applied for piezoelectric immunoassay of carbohydrate antigen 19-9.

PubMed

Ding, Yanjun; Liu, Jia; Jin, Xiaoyong; Lu, Haixia; Shen, Guoli; Yu, Ruqin

2008-02-01

Hybrid composites are of special scientific interest for biochemical applications wherein the abilities to modulate the morphology and property of the hybrid material are important. In this paper, the formation of poly-L-lysine/hydroxyapatite/carbon nanotube (PLL/HA/CNT) hybrid nanoparticles is described and a general design strategy for an immunosensing platform has been proposed on the basis of PLL/HA/CNT nanocomposite adsorption of antibodies. Quartz crystal microbalance (QCM) used as a model transducer and the detection performances of the resulting immunosensor were investigated by use of the immuno-system of carbohydrate antigen 19-9 (CA19-9), an important indicator in the diagnosis of clinical cancers. The hybrid nanocomposite was characterized by the transmission electron microscope (TEM), scanning electron microscope (SEM) and Fourier transform-infrared (FT-IR) spectrum measurements. The frequency response characteristics for the processes of immobilization and immunoreaction of anchored anti-CA19-9 antibodies were studied in detail. It was found that the developed sensing interface has some advantages such as the activation-free immobilization and the high antigen-binding activities of antibodies. The as-prepared immunosensor can allow for the determination of CA19-9 in the concentration range of around 12.5-270.0 U ml(-1). Such an interface design with the hybrid nanocomposite should be tailored as a new alternative used for biosensor design.

Spatial distributions, source apportionment and ecological risk of SVOCs in water and sediment from Xijiang River, Pearl River Delta.

PubMed

Tang, Jiao; An, Taicheng; Li, Guiying; Wei, Chaohai

2017-03-09

Xijiang River is an important drinking water source in Guangxi Province, China. Along the Xijiang River and surrounding tributary, the pollution profile of three important groups of semi-volatile organic compounds, including polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and phthalate esters (PAEs), was analyzed. Relatively low levels of PAHs (64-3.7 × 10 2  ng L -1 ) and OCPs (16-70 ng L -1 ), but high levels of PAEs (7.9 × 10 2 -6.8 × 10 3  ng L -1 ) occurred in the water. Comparatively, low levels of OCPs (39-1.8 × 10 2  ng g -1 ) and PAEs (21-81 ng g -1 ), but high levels of PAHs (41-1.1 × 10 3  ng g -1 ) were found in sediment. Principal component analyses for source identification indicated petroleum-derived residues or coal and biomass combustion, and vehicular emission was the main sources for PAHs. The OCPs sources of each category were almost independent, whereas the new input of HCHs and p,p'-DDTs probably existed in some areas. PAEs were mainly originated from personal care products of urban sewage, plastic and other industrial sources. Ecological risk through the risk quotient analysis indicated a small or significant potential adverse effect on fish, daphnia and green algae. Nevertheless, the integrated risk of all pollutants should be taken into account in future study.

Concentrations and potential health hazards of organochlorine pesticides in (shallow) groundwater of Taihu Lake region, China.

PubMed

Wu, Chunfa; Luo, Yongming; Gui, Tong; Huang, Yujuan

2014-02-01

A total of 27 shallow groundwater samples were collected from the Taihu Lake region (TLR), to determine the concentrations of 14 organochlorine pesticide (OCP) species, identify their possible sources, and estimate health risk of drinking the shallow groundwater. All OCP species occurred in the shallow groundwater of TLR with high detection frequency except p, p'-dichlorodiphenyldichlorothane (p, p'-DDD) and p, p'-dichlorodiphenyltrichloroethane (p, p'-DDT). DDTs and hexachlorocyclohexanes (HCHs) were the dominant OCP contaminants in the shallow groundwater of TLR, and they account for 44.2% total OCPs. The low α-HCH/γ-HCH ratio, high β-HCH/(α+γ)-HCH ratio and β-HCH being the dominant HCH isomers for the majority of samples suggest that the HCHs were mainly from the historical use of lindane after a period of degradation. p, p'-DDE being the dominant DDT metabolite for all the samples indicated that the DDTs were mainly from the historical residues. Compositional analysis also suggested that there were fresh input sources of heptachlors, aldrins and endrins in addition to the historical residues. Correlation analysis indicated the hexachlorobenzene (HCB) impurity in the shallow groundwater of TLR was likely from the historical application of lindane and technical HCH (a mixture of HCH isomers that is produced by photochlorination of benzene). Carcinogenic risk values for α-HCH, heptachlor, heptachlor epoxide, aldrins and dieldrin in the shallow groundwater in majority area of TLR were found to be >10(-6), posing a potentially serious cancer risk to those dependant on shallow groundwater for drinking water. © 2013.

Pharmacy claims data versus patient self-report to measure contraceptive method continuation.

PubMed

Triebwasser, Jourdan E; Higgins, Stephanie; Secura, Gina M; Zhao, Qiuhong; Peipert, Jeffrey F

2015-07-01

To compare self-reported 12-month continuation of oral contraceptive pills (OCPs), patch, and ring versus continuation by pharmacy claims data. Women in the Contraceptive CHOICE Project who chose OCPs, the patch, or the ring as their initial method were included. Continuation was assessed by periodic telephone survey and by obtaining prescription claims data. Continuation was defined as no gap of more than 30 days. Kaplan-Meier survival functions were used to estimate continuation rates and cumulative unintended pregnancy rates. Kappa statistic assessed the level of agreement between self-report and claims data. We analyzed 1510 women who initiated use by 3 months and provided information on discontinuation. Of OCP users, 59% continued their method at 12 months by self-report versus 38% by pharmacy claims. Patch and ring users had self-reported/pharmacy continuation of 45%/28% and 57%/37%, respectively. Kappa coefficients and their 95% confidence intervals between the two measurements were 0.46 (0.40, 0.52), 0.54 (0.39, 0.68), and 0.54 (0.47, 0.61) for OCP, patch, and ring, respectively. Among women who self-reported continuation, unintended pregnancy rates were 0.4% in those who continued by pharmacy claims versus 4.9% in those who discontinued according to claims data. Contraceptive continuation rates differ by self-report versus pharmacy claims with women overestimating their continuation by self-report. This article directly compares contraception continuation rates by self-report and by pharmacy claims data. The study suggests that previously reported continuation rates from survey data overestimate specific method use. Copyright © 2015 Elsevier Inc. All rights reserved.

Prospective multicenter randomized intermediate biomarker study of oral contraceptive versus depo-provera for prevention of endometrial cancer in women with Lynch syndrome.

PubMed

Lu, Karen H; Loose, David S; Yates, Melinda S; Nogueras-Gonzalez, Graciela M; Munsell, Mark F; Chen, Lee-May; Lynch, Henry; Cornelison, Terri; Boyd-Rogers, Stephanie; Rubin, Mary; Daniels, Molly S; Conrad, Peggy; Milbourne, Andrea; Gershenson, David M; Broaddus, Russell R

2013-08-01

Women with Lynch syndrome have a 40% to 60% lifetime risk for developing endometrial cancer, a cancer associated with estrogen imbalance. The molecular basis for endometrial-specific tumorigenesis is unclear. Progestins inhibit estrogen-driven proliferation, and epidemiologic studies have shown that progestin-containing oral contraceptives (OCP) reduce the risk of endometrial cancer by 50% in women at general population risk. It is unknown whether they are effective in women with Lynch syndrome. Asymptomatic women ages 25 to 50 with Lynch syndrome were randomized to receive the progestin compounds Depo-Provera (depo-MPA) or OCP for three months. An endometrial biopsy and transvaginal ultrasound were conducted before and after treatment. Endometrial proliferation was evaluated as the primary endpoint. Histology and a panel of surrogate endpoint biomarkers were evaluated for each endometrial biopsy as secondary endpoints. A total of 51 women were enrolled, and 46 completed treatment. Two of the 51 women had complex hyperplasia with atypia at the baseline endometrial biopsy and were excluded from the study. Overall, both depo-MPA and OCP induced a dramatic decrease in endometrial epithelial proliferation and microscopic changes in the endometrium characteristic of progestin action. Transvaginal ultrasound measurement of endometrial stripe was not a useful measure of endometrial response or baseline hyperplasia. These results show that women with Lynch syndrome do show an endometrial response to short-term exogenous progestins, suggesting that OCP and depo-MPA may be reasonable chemopreventive agents in this high-risk patient population.

Prospective, Multi-center Randomized Intermediate Biomarker Study of Oral Contraceptive vs. Depo-Provera for Prevention of Endometrial Cancer in Women with Lynch Syndrome

PubMed Central

Lu, Karen H.; Loose, David S.; Yates, Melinda S.; Nogueras-Gonzalez, Graciela M.; Munsell, Mark F.; Chen, Lee-may; Lynch, Henry; Cornelison, Terri; Boyd-Rogers, Stephanie; Rubin, Mary; Daniels, Molly S.; Conrad, Peggy; Milbourne, Andrea; Gershenson, David M.; Broaddus, Russell R.

2013-01-01

Women with Lynch syndrome have a 40–60% lifetime risk for developing endometrial cancer, a cancer associated with estrogen imbalance. The molecular basis for endometrial-specific tumorigenesis is unclear. Progestins inhibit estrogen-driven proliferation, and epidemiologic studies have demonstrated that progestin-containing oral contraceptives (OCP) reduce the risk of endometrial cancer by 50% in women at general population risk. It is unknown if they are effective in women with Lynch syndrome. Asymptomatic women age 25–50 with Lynch syndrome were randomized to receive the progestin compounds depo-Provera (depoMPA) or OCP for three months. An endometrial biopsy and transvaginal ultrasound were performed before and after treatment. Endometrial proliferation was evaluated as the primary endpoint. Histology and a panel of surrogate endpoint biomarkers were evaluated for each endometrial biopsy as secondary endpoints. A total of 51 women were enrolled, and 46 completed treatment. Two of the 51 women had complex hyperplasia with atypia at the baseline endometrial biopsy and were excluded from the study. Overall, both depoMPA and OCP induced a dramatic decrease in endometrial epithelial proliferation and microscopic changes in the endometrium characteristic of progestin action. Transvaginal ultrasound measurement of endometrial stripe was not a useful measure of endometrial response or baseline hyperplasia. These results demonstrate that women with Lynch syndrome do show an endometrial response to short term exogenous progestins, suggesting that OCP and depoMPA may be reasonable chemopreventive agents in this high-risk patient population. PMID:23639481

A comparison of landscape fuel treatment strategies to mitigate wildland fire risk in the urban interface and preserve old forest structure

Treesearch

Alan Ager; Nicole Vaillant

2010-01-01

We simulated fuel reduction treatments on a 16,000-ha study area in Oregon, US, to examine tradeoffs between placing fuel treatments near residential structures within an urban interface, versus treating stands in the adjacent wildlands to meet forest health and ecological restoration goals. The treatment strategies were evaluated by simulating 10,000 wildfires with...

In vivo implant fixation of carbon fiber-reinforced PEEK hip prostheses in an ovine model.

PubMed

Nakahara, Ichiro; Takao, Masaki; Bandoh, Shunichi; Bertollo, Nicky; Walsh, William R; Sugano, Nobuhiko

2013-03-01

Carbon fiber-reinforced polyetheretherketone (CFR/PEEK) is theoretically suitable as a material for use in hip prostheses, offering excellent biocompatibility, mechanical properties, and the absence of metal ions. To evaluate in vivo fixation methods of CFR/PEEK hip prostheses in bone, we examined radiographic and histological results for cementless or cemented CFR/PEEK hip prostheses in an ovine model with implantation up to 52 weeks. CFR/PEEK cups and stems with rough-textured surfaces plus hydroxyapatite (HA) coatings for cementless fixation and CFR/PEEK cups and stems without HA coating for cement fixation were manufactured based on ovine computed tomography (CT) data. Unilateral total hip arthroplasty was performed using cementless or cemented CFR/PEEK hip prostheses. Five cementless cups and stems and six cemented cups and stems were evaluated. On the femoral side, all cementless stems demonstrated bony ongrowth fixation and all cemented stems demonstrated stable fixation without any gaps at both the bone-cement and cement-stem interfaces. All cementless cases and four of the six cemented cases showed minimal stress shielding. On the acetabular side, two of the five cementless cups demonstrated bony ongrowth fixation. Our results suggest that both cementless and cemented CFR/PEEK stems work well for fixation. Cup fixation may be difficult for both cementless and cemented types in this ovine model, but bone ongrowth fixation on the cup was first seen in two cementless cases. Cementless fixation can be achieved using HA-coated CFR/PEEK implants, even under load-bearing conditions. Copyright © 2012 Orthopaedic Research Society.

Food safety traits of mussels and clams: distribution of PCBs, PBDEs, OCPs, PAHs and PFASs in sample from different areas using HRMS-Orbitrap® and modified QuEChERS extraction followed by GC-MS/MS.

PubMed

Chiesa, Luca Maria; Nobile, Maria; Malandra, Renato; Pessina, Davide; Panseri, Sara; Labella, Giuseppe Federico; Arioli, Francesco

2018-05-01

Reviewing the presence of contaminant residues is important both for food safety and for monitoring of environmental pollution. Here, the occurrence of 6 polychlorinated biphenyls (PCBs), 15 organochlorine pesticides (OCPs), 7 polybrominated diphenyl ethers (PBDEs), 4 polycyclic aromatic hydrocarbons (PAHs) and 17 perfluoroalkyl substances (PFASs) was evaluated in mussels and clams. A liquid chromatography-high resolution mass spectrometry (HPLC-HRMS) and an innovative QuEChERS extraction followed by gas chromatography-tandem mass spectrometry (GC-MS/MS) methods were developed, validated and applied. We demonstrate good linearity, repeatability and accuracy of these methods, confirming that they are suitable for the analyses of mollusc samples. The prevalence of PCBs, OCPs and PAHs was higher in mussels than in clams. For PFASs, contamination was higher in clams than in mussels. The samples were all compliant with the regulations, and, for the compounds without legislative limits, a risk assessment confirmed that the values were lower than the tolerable intakes.

Tracking residual organochlorine pesticides (OCPs) in green, herbal, and black tea leaves and infusions of commercially available tea products marketed in Poland.

PubMed

Witczak, Agata; Abdel-Gawad, Hassan; Zalesak, Michal; Pohoryło, Anna

2018-03-01

The content of residual organochlorine pesticides (OCPs) was examined in green, herbal, and black tea leaves as well as in their infusions prepared from tea products marketed in the main supermarkets in Poland. It was found that the detected mean levels of organochlorine residues in tea leaves ranged from

Insights into the Structural Changes Occurring upon Photoconversion in the Orange Carotenoid Protein from Broadband Two-Dimensional Electronic Spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

De Re, Eleonora; Schlau-Cohen, Gabriela S.; Leverenz, Ryan L.

Carotenoids play an essential role in photoprotection, interacting with other pigments to safely dissipate excess absorbed energy as heat. In cyanobacteria, the short time scale photoprotective mechanisms involve the photoactive orange carotenoid protein (OCP), which binds a single carbonyl carotenoid. Blue-green light induces the photoswitching of OCP from its ground state form (OCPO) to a metastable photoproduct (OCPR). OCPR can bind to the phycobilisome antenna and induce fluorescence quenching. The photoswitching is accompanied by structural and functional changes at the level of the protein and of the bound carotenoid. In this study, we use broadband two-dimensional electronic spectroscopy to lookmore » at the differences in excited state dynamics of the carotenoid in the two forms of OCP. Our results provide insight into the origin of the pronounced vibrational lineshape and oscillatory dynamics observed in linear absorption and 2D electronic spectroscopy of OCPO and the large inhomogeneous broadening in OCPR, with consequences for the chemical function of the two forms.« less

Development of a rapid screening technique for organochlorine pesticides using solvent microextraction (SME) and fast gas chromatography (GC).

PubMed

de Jager, L S; Andrews, A R

2000-11-01

A novel, fast screening method for organochlorine pesticides (OCPs) in water samples has been developed. Total analysis time was less than 9 min, allowing 11 samples to be screened per hour. The relatively new technique of solvent microextraction (SME) was used to extract and preconcentrate the pesticides into a single drop of hexane. The use of a conventional carbon dioxide cryotrap was investigated for introduction of the extract onto a micro-bore (0.1 mm) capillary column for fast GC analysis. A pulsed-discharge electron capture detector was used which yielded selective and sensitive measurement of the pesticide peaks. Fast GC conditions were optimised and tested with the previously developed SME procedure. Calibration curves yielded good linearity and concentrations down to 0.25 ng mL-1 were detectable with RSD values ranging from 12.0 to 28% and LOD for most OCPs at 0.25 ng mL-1. Spiked river water samples were tested and using the developed screen we were able to differentiate between spiked samples and samples containing no OCPs.

Magnetic porous carbon derived from a bimetallic metal-organic framework for magnetic solid-phase extraction of organochlorine pesticides from drinking and environmental water samples.

PubMed

Liu, Yaxi; Gao, Zongjun; Wu, Ri; Wang, Zhenhua; Chen, Xiangfeng; Chan, T-W Dominic

2017-01-06

In this work, magnetic porous carbon material derived from a bimetallic metal-organic framework was explored as an adsorbent for magnetic solid-phase extraction of organochlorine pesticides (OCPs). The synthesized porous carbon possessed a high specific surface area and magnetization saturation. The OCPs in the samples were quantified using gas chromatography coupled with a triple quadrupole mass spectrometer. The experimental parameters, including the desorption solvent and conditions, amount of adsorbent, extraction time, extraction temperature, and ionic strength of the solution, were optimized. Under optimal conditions, the developed method displayed good linearity (r>0.99) within the concentration range of 2-500ngL -1 . Low limits of detection (0.39-0.70ngL -1 , signal-to-noise ratio=3:1) and limits of quantification (1.45-2.0ngL -1 , signal-to-noise ratio=10:1) as well as good precision (relative standard deviation<10%) were also obtained. The developed method was applied in the analysis of OCPs in drinking and environmental water samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Polarization Resistance Measurement in Tap Water: The Influence of Rust Electrochemical Activity

NASA Astrophysics Data System (ADS)

Vasyliev, Georgii

2017-08-01

Corrosion rate of mild steel in tap water during 4300 h was estimated by LPR and weight-loss methods coupled with OCP measurements. The LPR results were found to be overestimated compared to the weight-loss data within initial 2000 h of exposure. The electrochemical activity of the rust separated from the metal surface was studied by cycling voltammetry using a home-built powder graphite electrode. High redox currents corresponding to the initial 2000 h of exposure were detected. Rust composition was characterized with IR and XRD, and the highest amounts of electrochemically active β- and γ-FeOOH were again detected for the initial 2000 h. Current consumption in rust transformation processes during LPR measurement in the galvanostatic mode accounts for overestimation of the corrosion rate. The time dependence of rust electrochemical activity correlates with OCP variation with time. During initial 2000 h, OCP values are shifted by 50 mV to cathodic side. For the period of a higher rust electrochemical activity, the use of a reduced B is suggested to increase accuracy of LPR technique in tap water.

Surface microstructures and corrosion resistance of Ni-Ti-Nb shape memory thin films

NASA Astrophysics Data System (ADS)

Li, Kun; Li, Yan; Huang, Xu; Gibson, Des; Zheng, Yang; Liu, Jiao; Sun, Lu; Fu, Yong Qing

2017-08-01

Ni-Ti-Nb and Ni-Ti shape memory thin films were sputter-deposited onto silicon substrates and annealed at 600 °C for crystallization. X-ray diffraction (XRD) measurements indicated that all of the annealed Ni-Ti-Nb films were composed of crystalline Ni-Ti (Nb) and Nb-rich grains. X-ray photoelectron spectroscopy (XPS) tests showed that the surfaces of Ni-Ti-Nb films were covered with Ti oxides, NiO and Nb2O5. The corrosion resistance of the Ni-Ti-Nb films in 3.5 wt.% NaCl solution was investigated using electrochemical tests such as open-circuit potential (OCP) and potentio-dynamic polarization tests. Ni-Ti-Nb films showed higher OCPs, higher corrosion potentials (Ecorr) and lower corrosion current densities (icorr) than the binary Ni-Ti film, which indicated a better corrosion resistance. The reason may be that Nb additions modified the passive layer on the film surface. The OCPs of Ni-Ti-Nb films increased with further Nb additions, whereas no apparent difference of Ecorr and icorr was found among the Ni-Ti-Nb films.

Air-soil exchange of organochlorine pesticides in a sealed chamber.

PubMed

Yang, Bing; Han, Baolu; Xue, Nandong; Zhou, Lingli; Li, Fasheng

2015-01-01

So far little is known about air-soil exchange under any sealed circumstances (e.g., in plastic and glass sheds), which however has huge implications for the soil-air-plant pathways of persistent organic pollutants including organochlorine pesticides (OCPs). A newly designed passive air sampler was tested in a sealed chamber for measuring the vertical concentration profiles of gaseous phase OCPs (hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs)). Air was sampled at 5, 15, and 30 cm above ground level every 10th day during a 60-day period by deploying polyurethane foam cylinders housed in acrylonitrile butadiene styrene-covered cartridges. Concentrations and compositions of OCPs along the vertical sections indicated a clear relationship with proximity to the mixture of HCHs and DDTs which escapes from the soils. In addition, significant positive correlations were found between air temperatures and concentrations of HCHs and DDTs. These results indicated revolatilization and re-deposition being at or close to dynamic pseudo-equilibrium with the overlying air. The sampler used for addressing air-soil exchange of persistent organic pollutants in any sealed conditions is discussed. Copyright © 2014. Published by Elsevier B.V.

Molecular dynamics simulations for the examination of mechanical properties of hydroxyapatite/ poly α-n-butyl cyanoacrylate under additive manufacturing.

PubMed

Wang, Yanen; Wei, Qinghua; Pan, Feilong; Yang, Mingming; Wei, Shengmin

2014-01-01

Molecular dynamics (MD) simulations emerged to be a helpful tool in the field of material science. In rapid prototyping artificial bone scaffolds process, the binder spraying volume and mechanism are very important for bone scaffolds mechanical properties. In this study, we applied MD simulations to investigating the binding energy of α-n-butyl cyanoacrylate (NBCA) on Hydroxyapatite (HA) crystallographic planes (001, 100 and 110), and to calculating and analyzing the mechanical properties and radial distribution function of the HA(110)/NBCA mixed system. The simulation results suggested that HA (110) has the highest binding energy with NBCA owing to the high planar atom density, and the mechanical properties of HA(110)/NBCA mixed system is stronger than pure HA system. Therefore, the multi-grade strength bone scaffold could be fabricated through spraying various volume NBCA binders during 3D printing process. By calculating the radial distribution function of HA(110)/NBCA, the essence of the interface interaction were successfully elucidated. The forming situation parameters can be referred to calculation results. There exists a strong interaction between HA crystallographic plane (110) and NBCA, it is mainly derived from the hydrogen bonds between O atoms which connect with C atoms of NBCA and H atoms in HA crystal. Furthermore, a strong adsorption effect can be demonstrated between HA and NBCA.

Performance Characteristics For The Orbiter Camera Payload System's Large Format Camera (LFC)

NASA Astrophysics Data System (ADS)

MoIIberg, Bernard H.

1981-11-01

The Orbiter Camera Payload System, the OCPS, is an integrated photographic system which is carried into Earth orbit as a payload in the Shuttle Orbiter vehicle's cargo bay. The major component of the OCPS is a Large Format Camera (LFC) which is a precision wide-angle cartographic instrument that is capable of produc-ing high resolution stereophotography of great geometric fidelity in multiple base to height ratios. The primary design objective for the LFC was to maximize all system performance characteristics while maintaining a high level of reliability compatible with rocket launch conditions and the on-orbit environment.

CYP17A1 gene polymorphisms and environmental exposure to organochlorine pesticides contribute to the risk of small for gestational age.

PubMed

Chand, S; Mustafa, M D; Banerjee, B D; Guleria, K

2014-09-01

The cytochrome P-450c17α enzyme encoded by the cytochrome P-450c17α (CYP17A1) gene plays a role in oestrogen synthesis. Genetic variation in the maternal CYP17A1 gene leads to differences in oestrogen level that affect fetal growth and cause small for gestational age (SGA). Organochlorine pesticides (OCPs) are endocrine disruptors that alter the normal oestrogen-progesterone balance, and are associated with adverse reproductive outcomes. This study was designed to investigate the effect of the gene-environment interaction between maternal CYP17A1 gene polymorphisms and maternal and cord OCP levels on the risk of SGA. Maternal and cord blood samples of 50 term SGA cases (birth weight <10th percentile for gestational age as per Lubchenco's growth chart) and 50 normal pregnancies (controls) were collected. Women with occupational exposure to OCPs, anaemia, hypertension, antiphospholipid antibody syndrome, medical disease, parity of more than four, or a history of smoking, alcohol consumption or chronic drug intake were excluded from both groups. Maternal and cord blood samples were collected at the time of delivery or after delivery, respectively. The OCP levels of the samples were analyzed using a gas chromatography system equipped with an electron capture detector, and polymerase chain reaction-restriction fragment length polymorphism was used for polymorphic analysis of the CYP17A1 gene. Significantly (p<0.05) higher levels of α-hexachlorocyclohexane (HCH), β-HCH and γ-HCH were found in maternal and cord blood samples of the SGA cases compared with the controls. The frequency of the A1A2/A2A2 genotype was significantly lower [p=0.041, odds ratio (OR) 0.421, 95% confidence interval (CI) 0.184-0.966] in the SGA cases compared with the controls. When gene-environment interactions between CYP17A1 gene polymorphisms and OCP levels were considered, a significant (p=0.004) association was found between a high level of endosulfan in cord blood and the A1A1 (wild-type) genotype of CYP17A1, leading to an estimated reduction in birth weight of 315g. Higher OCP levels and the A1A1 genotype of CYP17A1 in pregnant women may be considered as important aetiological factors in idiopathic SGA. This study provides evidence that genetic variation and its interaction with environmental exposure may increase the risk of SGA. Further studies are needed with a larger sample size, incorporating other gene polymorphisms and environmental exposures, to strengthen these observations. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Motion representation of the long fingers: a proposal for the definitions of new anatomical frames.

PubMed

Coupier, Jérôme; Moiseev, Fédor; Feipel, Véronique; Rooze, Marcel; Van Sint Jan, Serge

2014-04-11

Despite the availability of the International Society of Biomechanics (ISB) recommendations for the orientation of anatomical frames, no consensus exists about motion representations related to finger kinematics. This paper proposes novel anatomical frames for motion representation of the phalangeal segments of the long fingers. A three-dimensional model of a human forefinger was acquired from a non-pathological fresh-frozen hand. Medical imaging was used to collect phalangeal discrete positions. Data processing was performed using a customized software interface ("lhpFusionBox") to create a specimen-specific model and to reconstruct the discrete motion path. Five examiners virtually palpated two sets of landmarks. These markers were then used to build anatomical frames following two methods: a reference method following ISB recommendations and a newly-developed method based on the mean helical axis (HA). Motion representations were obtained and compared between examiners. Virtual palpation precision was around 1mm, which is comparable to results from the literature. The comparison of the two methods showed that the helical axis method seemed more reproducible between examiners especially for secondary, or accessory, motions. Computed Root Mean Square distances comparing methods showed that the ISB method displayed a variability 10 times higher than the HA method. The HA method seems to be suitable for finger motion representation using discrete positions from medical imaging. Further investigations are required before being able to use the methodology with continuous tracking of markers set on the subject's hand. Copyright © 2014 Elsevier Ltd. All rights reserved.

Characterization and human gingival fibroblasts biocompatibility of hydroxyapatite/PMMA nanocomposites for provisional dental implant restoration

NASA Astrophysics Data System (ADS)

Zhang, Jingchao; Liao, Juan; Mo, Anchun; Li, Yubao; Li, Jidong; Wang, Xuejiang

2008-11-01

The aim of this study was to determine nHA/PMMA composites (H/P) in an optimal ratio with improved cytocompatibility as well as valid physical properties for provisional dental implant restoration. 20 wt.%, 30 wt.%, 40 wt.% and 50 wt.% H/P were developed and characterized using XPS, bending strength test and SEM. Human gingival fibroblasts cultured in extracts or directly on sample discs were investigated by fluorescent staining and MTT assay. Chemical integration in nHA/PMMA interface was indicated by XPS. Typical fusiform cells with adhesion spots were detected on H/P discs. MTT results also indicated higher cell viability in 30 wt.% and 40 wt.% H/P discs ( P < 0.05). We conclude that nHA addition to PMMA enhances cytocompatibility and the optimal nHA/PMMA ratio for provisional fixed crowns (PFC) is 0.4:1.

Organic pollutant levels in an agricultural watershed: the importance of analyzing multiple matrices for assessing stream water pollution.

PubMed

Gonzalez, Mariana; Miglioranza, Karina S B; Grondona, Sebastían I; Silva Barni, Maria Florencia; Martinez, Daniel E; Peña, Aránzazu

2013-04-01

This study is aimed at analyzing the occurrence and transport of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in the Quequén Grande river basin, as representative of a catchment under diffuse pollution sources. Pollutant levels in soils, river bottom sediments (RBS), streamwater (Sw), suspended particle materials (SPMs), macrophytes and muscle of silverside were determined by GC-ECD. Soil K(d) values for the current-used insecticides, endosulfans and cypermethrin, were established. Total levels (ng g(-1) dry weight) in soil ranged between 0.07–0.9 for OCPs, 0.03–0.37 for PCBs and 0.01–0.05 for PBDEs. Endosulfan insecticide (α- + b- + sulfate metabolite) represented up to 72.5% of OCPs. The low soil retention for α-endosulfan (K(d): 77) and endosulfan sulfate (K(d): 100) allows their transport to Sw, SPM and RBS. Levels of endosulfan in Sw in some cases exceeded the value postulated by international guidelines for aquatic biota protection (3 ng L(-1)). PCB and PBDE pollution was related to harbour, dumping sites and pile tire burning. Tri and hexa PCB congeners predominated in all matrices and exceeded the quality guideline value of 0.04 ng L(-1) in Sw. Considering levels in silverside muscle, none of the oral reference doses were exceeded, however, PCBs accounted for 18.6% of the total daily allowed ingest for a 70 kg individual. Although the levels of PCBs and OCPs in soil and RBS were low and did not go beyond quality guidelines, these compounds could still represent a risk to aquatic biota and humanbeings, and thus actions towards preventing this situation should be undertaken.

Levels and profiles of organochlorines and flame retardants in car and house dust from Kuwait and Pakistan: implication for human exposure via dust ingestion.

PubMed

Ali, Nadeem; Ali, Lulwa; Mehdi, Toufeer; Dirtu, Alin C; Al-Shammari, Fatema; Neels, Hugo; Covaci, Adrian

2013-05-01

There are only few studies documenting indoor pollution in the Middle East and the Indian subcontinent. In present study, we have evaluated the occurrence of various organochlorines (OCs) and flame retardants (FRs) in dust from cars and houses of Pakistan and Kuwait. Polybrominated diphenyl ethers (PBDEs), novel brominated flame retardants (NBFRs), organophosphate FRs (PFRs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) were investigated in indoor dust from urban houses (N=15 per country) and cars (N=15 per country). PFRs were the major analytes in all four microenvironments, followed by PBDEs>NBFRs>OCPs>PCBs. For all classes of analytes, relatively lower levels were observed in car and house dust from Pakistan than Kuwait. Levels of ∑PBDEs, ∑NBFRs and ∑PFRs were higher in car dust, while ∑OCPs and ∑PCBs were higher in house dust from both countries. ∑PFRs occurred at average concentrations of 16,900, 87,900, 475, and 2500ng/g in Kuwaiti house and car, and Pakistani house and car dust, respectively. For both countries, the profiles of analytes in car dust were different from those in the house dust. Different exposure scenarios using 5th percentile, median, mean, and 95th percentile levels were estimated for adult, taxi drivers and toddlers. For Kuwaiti toddlers, assuming high dust intake and mean and 95th percentile concentrations, the values computed for ∑OCPs (1500ng/kg bw/day) were higher than RfD values, while for ∑PCBs (14.5ng/kg bw/day) it was only two-fold lower than the corresponding RfDs. Copyright © 2013 Elsevier Ltd. All rights reserved.

Concentrations of organochlorine pesticides, polybrominated diphenyl ethers and perfluorinated compounds in the atmosphere of North Greenland.

PubMed

Bossi, Rossana; Vorkamp, Katrin; Skov, Henrik

2016-10-01

Atmospheric concentrations of organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs) and neutral per- and polyfluoroalkyl substances (PFAS) have been measured at Villum Research Station, Station Nord (North Greenland) in the period 2008-2013. Atmospheric concentrations of OCPs at the same site have been previously reported for the years 2008-2010. The detection frequency and the average concentrations of OCPs have not significantly changed since the previous study. PBDE congeners (∑13PBDEs) were measured for the first time in North Greenland at concentrations similar to those observed for other remote sites, confirming that these compounds are ubiquitous in the Northern Hemisphere. The ∑13PBDEs concentration ranged from not detected (n.d.) to 6.26 pg m(-3). The BDE congeners found in more than 30% of the samples were BDE-17, BDE-28, BDE-47, BDE-71, BDE-99 and BDE-100. Also for neutral PFAS we present for the first time a multiyear series of measurements for North Greenland. The average sum of the seven measured neutral PFAS (∑7PFAS) ranged from 1.82 to 32.1 pg m(-3). The most abundant compound was 8:2 FTOH (44% of ∑7PFAS), followed by 6:2 FTOH and 10:2 FTOH. Perfluoroalkyl sulfonamides (FOSA) and perfluoroalkyl sulfonamidoethanols (FOSE) were also detected but at much lower concentrations than FTOHs. Temporal trends were investigated for all measured compounds but no significant trend in concentration was observed. Monthly average concentrations for the six years were calculated for each compound and the seasonal variation was investigated. Some OCPs and FTOHs showed seasonal variations, and in most cases a maximum was found during summer. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of landscape tree cover, sex and season on the bioaccumulation of persistent organochlorine pesticides in fruit bats of riparian corridors in eastern Mexico.

PubMed

Valdespino, Carolina; Sosa, Vinicio J

2017-05-01

Riparian forests are recognized as important ecosystems for biodiversity conservation in transformed landscapes. Many animal species that use this type of vegetation facilitate its recovery through pollination and seed dispersal. In landscapes dominated by agrosystems and cattle ranching, persistent organochlorine pesticides (OCPs) in the riparian system may have an effect on the physiology and fitness of animals. In this study, we measured bioaccumulation of OCPs in the most abundant frugivorous bat, Sturnira hondurensis, from the upper part of La Antigua basin, Veracruz, Mexico and, from these data, estimated accumulation by the frugivorous bat community of riparian forests in contrasting, transformed (TL) and forested (FL) landscapes. Concentration of ΣDDT, Σdrines, Σclordano, ΣHCH, Σheptachlor and Σendosulfan was measured by gas-chromatography in 23 female and 33 male adult Sturnira captured during the dry and rainy seasons. Using censored data statistics, we found that the sex of the individual was significant for ΣHCH, and that interactions of landscape type (TL vs. FL) and season (dry vs. wet), and sex and season were significant for Σendosulfan and Σdrines, respectively. Mean ΣDDT (6.86 μg/g) and ΣHCH (28.22 μg/g) concentrations were lower than those reported for frugivorous bats in India but concentrations of Σdrines (13.86 μg/g) were higher than those reported in insectivorous bats. In our study sites, frugivorous bats are bioaccumulating higher amounts of OCPs in TL than in FL. We discuss the potential of this species as a bio-indicator of OCPs contamination in river basins. Copyright © 2017. Published by Elsevier Ltd.

Optimal management of idiopathic macular holes

PubMed Central

Madi, Haifa A; Masri, Ibrahim; Steel, David H

2016-01-01

This review evaluates the current surgical options for the management of idiopathic macular holes (IMHs), including vitrectomy, ocriplasmin (OCP), and expansile gas use, and discusses key background information to inform the choice of treatment. An evidence-based approach to selecting the best treatment option for the individual patient based on IMH characteristics and patient-specific factors is suggested. For holes without vitreomacular attachment (VMA), vitrectomy is the only option with three key surgical variables: whether to peel the inner limiting membrane (ILM), the type of tamponade agent to be used, and the requirement for postoperative face-down posturing. There is a general consensus that ILM peeling improves primary anatomical hole closure rate; however, in small holes (<250 µm), it is uncertain whether peeling is always required. It has been increasingly recognized that long-acting gas and face-down positioning are not always necessary in patients with small- and medium-sized holes, but large (>400 µm) and chronic holes (>1-year history) are usually treated with long-acting gas and posturing. Several studies on posturing and gas choice were carried out in combination with ILM peeling, which may also influence the gas and posturing requirement. Combined phacovitrectomy appears to offer more rapid visual recovery without affecting the long-term outcomes of vitrectomy for IMH. OCP is licensed for use in patients with small- or medium-sized holes and VMA. A greater success rate in using OCP has been reported in smaller holes, but further predictive factors for its success are needed to refine its use. It is important to counsel patients realistically regarding the rates of success with intravitreal OCP and its potential complications. Expansile gas can be considered as a further option in small holes with VMA; however, larger studies are required to provide guidance on its use. PMID:26834454

Optimal management of idiopathic macular holes.

PubMed

Madi, Haifa A; Masri, Ibrahim; Steel, David H

2016-01-01

This review evaluates the current surgical options for the management of idiopathic macular holes (IMHs), including vitrectomy, ocriplasmin (OCP), and expansile gas use, and discusses key background information to inform the choice of treatment. An evidence-based approach to selecting the best treatment option for the individual patient based on IMH characteristics and patient-specific factors is suggested. For holes without vitreomacular attachment (VMA), vitrectomy is the only option with three key surgical variables: whether to peel the inner limiting membrane (ILM), the type of tamponade agent to be used, and the requirement for postoperative face-down posturing. There is a general consensus that ILM peeling improves primary anatomical hole closure rate; however, in small holes (<250 µm), it is uncertain whether peeling is always required. It has been increasingly recognized that long-acting gas and face-down positioning are not always necessary in patients with small- and medium-sized holes, but large (>400 µm) and chronic holes (>1-year history) are usually treated with long-acting gas and posturing. Several studies on posturing and gas choice were carried out in combination with ILM peeling, which may also influence the gas and posturing requirement. Combined phacovitrectomy appears to offer more rapid visual recovery without affecting the long-term outcomes of vitrectomy for IMH. OCP is licensed for use in patients with small- or medium-sized holes and VMA. A greater success rate in using OCP has been reported in smaller holes, but further predictive factors for its success are needed to refine its use. It is important to counsel patients realistically regarding the rates of success with intravitreal OCP and its potential complications. Expansile gas can be considered as a further option in small holes with VMA; however, larger studies are required to provide guidance on its use.

Characterising the individual health risk in infants exposed to organochlorine pesticides via breast milk by applying appropriate margins of safety derived from estimated daily intakes.

PubMed

Hernik, A; Góralczyk, K; Struciński, P; Czaja, K; Korcz, W; Minorczyk, M; Lyczewska, M; Ludwicki, J K

2014-01-01

Milk secretion being an important way of elimination of organochlorine pesticides (OCPs) poses a concern due to potential risk for breastfed infants. This study aims to provide a tool for assessing such risks to infants exposed to OCPs (through accumulation in the mother's body), using calculated individual margins of safety (MoS). Selected OCPs included; p,p'-DDT, p,p'-DDD, p,p'-DDE, β-HCH, γ-HCH and HCB which were analysed in 28 samples of maternal milk. The highest intakes were recorded for p,p'-DDE (at 2.90 μg kg(-1)bw d(-1)) whilst the lowest was for γ-HCH, (at 0.019 μg kg(-1)bwd(-1)). For the risk characterisation purposes MoSs were calculated for the compounds for which toxicological reference values (e.g. ADI, TDI) were adopted. The MoS for average ∑DDT concentrations was found to be relatively low (2.82) somewhat similar to that for HCB at 7.08, and for γ-HCH, the MoS was substantially higher at 263.1. This, however does not take into account the extremely high individual concentrations. Thus, it was decided to calculate estimated daily intake (EDI) values based on OCP levels in individual milk samples. MoS levels of <1 (meaning unacceptable risk) were noted both for HCB in one sample as well as for ∑DDT in 3 samples indicating likely threats to infant's health. The lowest MoS noted for γ-HCH equalled to 60.6, indicating that this compound was not a threat to the health of any of the breastfed infants from the study group. Copyright © 2013. Published by Elsevier Ltd.

Temporal occurrence and sources of persistent organic pollutants in suspended particulate matter from the most heavily polluted river mouth of Lake Chaohu, China.

PubMed

Liu, Cheng; Zhang, Lei; Fan, Chengxin; Xu, Fuliu; Chen, Kaining; Gu, Xiaozhi

2017-05-01

The Nanfei River is by many measures the most heavily polluted tributary to Lake Chaohu. In this study, the temporal occurrence and sources of four classes of persistent organic pollutants (POPs), including polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs), in suspended particulate matter (SPM) from the river mouth were investigated monthly during 2014. Results show that concentrations of all four POPs in SPM were higher than those in the sediment of Lake Chaohu. PBDEs (26.7 ng g -1 dry weight (dw)) were originated mainly from commercial deca-BDE mixtures. PCB concentrations (1.336 ng g -1 dw) were lower than those of sediments in many other water bodies worldwide. PAHs (2597 ng g -1 dw) and OCPs (57.38 ng g -1 dw) were the most common POPs. PAHs mainly had high molecular weights and originated from pyrolytic sources, with a small proportion of petrogenic origin. The predominant OCPs were DDTs, heptachlorepoxides, dieldrin, hexachlorocyclohexanes, hexachlorobenzene, and chlordanes. Most OCPs originated from historical use, except lindane. Generally, of all the POPs studied, those of primary ecological concern should be acenaphthene, fluorene, DDTs, and chlordanes. Higher concentrations of POPs were detected during winter and spring than in summer and autumn, probably because of the high river flow during the rainy season. The high concentration of POPs in the riverine SPM and the fractionation of POPs in the water and SPM of the river should be a focal point in the future study of Lake Chaohu. Copyright © 2017 Elsevier Ltd. All rights reserved.

A comparison between monophasic levonorgestrel-ethinyl estradiol 150/30 and triphasic levonorgestrel-ethinyl estradiol 50-75-125/30-40-30 contraceptive pills for side effects and patient satisfaction: a study in Iran.

PubMed

Kashanian, Maryam; Shahpourian, Farangis; Zare, Omolbanin

2010-05-01

Oral contraceptive pills (OCPs) are one of the most effective reversible and accessible contraceptives, and patient acceptance for their use depends partly on the unfavorable adverse effects. The present study compared the two kinds of OCPs (monophasic; levonorgestrel (LNG)-ethinyl estradiol (EE) 150/30 versus triphasic; LNG-EE 50-75-125/30-40-30) for adverse effects and patient satisfaction. A randomized clinical trial was performed on 314 women who used OCPs for the first time, as their contraception, for 6 months. Overall, 1884 cycles were studied. In the monophasic group (n=159 who finally finished the study), monophasic pills LNG-EE 150/30mcg, and in the triphasic group (n=155 who finally finished the study), triphasic pills LNG-EE 50-75-125/30-40-30 mcg were used. Statistical analysis was performed using SPSS 10: Chi square test, Fisher exact test and Student's t-test were used. There were no significant differences between the two groups for common side effects, including nausea, headache, nervousness, facial hyperpigmentation (chloasma), and body weight (increase or decrease) but breakthrough bleeding and spotting (BTB/S) were less in the triphasic group, occurring in 30 cycles (18.86%) versus 10 cycles (6.45%), P=0.009*. Patient satisfaction for the two OCPs was similar and high. The rates of side effects were low. It seems that the monophasic and triphasic pills are similar according to patient satisfaction and side effects; therefore there is no benefit of one over the other except for BTB/S, for which triphasic is superior. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

A survey of bonobo (Pan paniscus) oral contraceptive pill use in North American zoos.

PubMed

Agnew, Mary K; Asa, Cheryl S; Clyde, Victoria L; Keller, Dominique L; Meinelt, Audra

2016-09-01

Contraception is an essential tool in reproductive management of captive species. The Association of Zoos and Aquariums (AZA) Reproductive Management Center (RMC) gathers data on contraception use and provides recommendations. Although apes have been given oral contraceptive pills (OCPs) for at least 30 years, there have been no published reports with basic information on why the pill is administered, formulations and brands used, and effects on physiology and behavior. Here, we report survey results characterizing OCP use in bonobos (Pan paniscus) housed in North American zoos, as well as information accumulated in the RMC's Contraception Database. Of 26 females treated, there have been no failures and nine reversals. The most commonly administered OCP formulation in bonobos contained ethinyl estradiol (EE) 35 μg/norethindrone 1 mg. Few females on combined oral contraceptives (COCs) were given a continuous active pill regimen; a hormone-free interval of at least 5 days was allowed in most. Crushing the pill and mixing with juice or food was common. Females on COCs seldom experienced breakthrough estrus or bleeding, while these conditions were sometimes observed for females on continuous COCs. All females on COCs exhibited some degree of perineal swelling, with a mean score of 3 or 3+ most commonly reported. Behavioral changes included less sexual behavior, dominant females becoming subordinate, and a negative effect on mood. No appreciable change in weight was noted. Taken together, these results indicate that OCPs are an effective and reversible contraceptive option for bonobos that can be used by zoos and sanctuaries to limit reproduction. Zoo Biol. 35:444-453, 2016. © Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Quantification of octacalcium phosphate, authigenic apatite and detrital apatite in coastal sediments using differential dissolution and standard addition

NASA Astrophysics Data System (ADS)

Oxmann, J. F.; Schwendenmann, L.

2014-06-01

Knowledge of calcium phosphate (Ca-P) solubility is crucial for understanding temporal and spatial variations of phosphorus (P) concentrations in water bodies and sedimentary reservoirs. In situ relationships between liquid- and solid-phase levels cannot be fully explained by dissolved analytes alone and need to be verified by determining particular sediment P species. Lack of quantification methods for these species limits the knowledge of the P cycle. To address this issue, we (i) optimized a specifically developed conversion-extraction (CONVEX) method for P species quantification using standard additions, and (ii) simultaneously determined solubilities of Ca-P standards by measuring their pH-dependent contents in the sediment matrix. Ca-P minerals including various carbonate fluorapatite (CFAP) specimens from different localities, fluorapatite (FAP), fish bone apatite, synthetic hydroxylapatite (HAP) and octacalcium phosphate (OCP) were characterized by XRD, Raman, FTIR and elemental analysis. Sediment samples were incubated with and without these reference minerals and then sequentially extracted to quantify Ca-P species by their differential dissolution at pH values between 3 and 8. The quantification of solid-phase phosphates at varying pH revealed solubilities in the following order: OCP > HAP > CFAP (4.5% CO3) > CFAP (3.4% CO3) > CFAP (2.2% CO3) > FAP. Thus, CFAP was less soluble in sediment than HAP, and CFAP solubility increased with carbonate content. Unspiked sediment analyses together with standard addition analyses indicated consistent differential dissolution of natural sediment species vs. added reference species and therefore verified the applicability of the CONVEX method in separately determining the most prevalent Ca-P minerals. We found surprisingly high OCP contents in the coastal sediments analyzed, which supports the hypothesis of apatite formation by an OCP precursor mechanism.

Quantification of octacalcium phosphate, authigenic apatite and detrital apatite in coastal sediments using differential dissolution and standard addition

NASA Astrophysics Data System (ADS)

Oxmann, J. F.; Schwendenmann, L.

2014-01-01

Knowledge of calcium phosphate (Ca-P) solubility is crucial for understanding temporal and spatial variations of phosphorus (P) concentrations in water bodies and sedimentary reservoirs. In-situ relationships between liquid and solid-phase levels cannot be fully explained by dissolved analytes alone and need to be verified by determination of particular sediment P species. Lack of quantification methods for these species limits the knowledge of the P cycle. To address this issue, we (i) optimized a specifically developed conversion-extraction (CONVEX) method for P species quantification using standard additions; and (ii) simultaneously determined solubilities of Ca-P standards by measuring their pH-dependent contents in the sediment matrix. Ca-P minerals including various carbonate fluorapatite (CFAP) specimens from different localities, fluorapatite (FAP), fish bone apatite, synthetic hydroxylapatite (HAP) and octacalcium phosphate (OCP) were characterized by XRD, Raman, FTIR and elemental analysis. Sediment samples were incubated with and without these reference minerals and then sequentially extracted to quantify Ca-P species by their differential dissolution at pH values between 3 and 8. The quantification of solid-phase phosphates at varying pH revealed solubilities in the following order: OCP > HAP > CFAP (4.5% CO3) > CFAP (3.4% CO3) > CFAP (2.2% CO3) > FAP. Thus, CFAP was less soluble in sediment than HAP, and CFAP solubility increased with carbonate content. Unspiked sediment analyses together with standard addition analyses indicated consistent differential dissolution of natural sediment species vs. added reference species and therefore verified the applicability of the CONVEX method in separately determining the most prevalent Ca-P minerals. We found surprisingly high OCP contents in the analyzed coastal sediments which supports the hypothesis of apatite formation by an OCP precursor.

20 Years of Air-Water Gas Exchange Observations for Pesticides in the Western Arctic Ocean.

PubMed

Jantunen, Liisa M; Wong, Fiona; Gawor, Anya; Kylin, Henrik; Helm, Paul A; Stern, Gary A; Strachan, William M J; Burniston, Deborah A; Bidleman, Terry F

2015-12-01

The Arctic has been contaminated by legacy organochlorine pesticides (OCPs) and currently used pesticides (CUPs) through atmospheric transport and oceanic currents. Here we report the time trends and air-water exchange of OCPs and CUPs from research expeditions conducted between 1993 and 2013. Compounds determined in both air and water were trans- and cis-chlordanes (TC, CC), trans- and cis-nonachlors (TN, CN), heptachlor exo-epoxide (HEPX), dieldrin (DIEL), chlorobornanes (ΣCHBs and toxaphene), dacthal (DAC), endosulfans and metabolite endosulfan sulfate (ENDO-I, ENDO-II, and ENDO SUL), chlorothalonil (CHT), chlorpyrifos (CPF), and trifluralin (TFN). Pentachloronitrobenzene (PCNB and quintozene) and its soil metabolite pentachlorothianisole (PCTA) were also found in air. Concentrations of most OCPs declined in surface water, whereas some CUPs increased (ENDO-I, CHT, and TFN) or showed no significant change (CPF and DAC), and most compounds declined in air. Chlordane compound fractions TC/(TC + CC) and TC/(TC + CC + TN) decreased in water and air, while CC/(TC + CC + TN) increased. TN/(TC + CC + TN) also increased in air and slightly, but not significantly, in water. These changes suggest selective removal of more labile TC and/or a shift in chlordane sources. Water-air fugacity ratios indicated net volatilization (FR > 1.0) or near equilibrium (FR not significantly different from 1.0) for most OCPs but net deposition (FR < 1.0) for ΣCHBs. Net deposition was shown for ENDO-I on all expeditions, while the net exchange direction of other CUPs varied. Understanding the processes and current state of air-surface exchange helps to interpret environmental exposure and evaluate the effectiveness of international protocols and provides insights for the environmental fate of new and emerging chemicals.

Amine-functionalized MIL-53(Al)-coated stainless steel fiber for efficient solid-phase microextraction of synthetic musks and organochlorine pesticides in water samples.

PubMed

Xie, Lijun; Liu, Shuqin; Han, Zhubing; Jiang, Ruifen; Zhu, Fang; Xu, Weiqin; Su, Chengyong; Ouyang, Gangfeng

2017-09-01

The fiber coating is the key part of the solid-phase microextraction (SPME) technique, and it determines the sensitivity, selectivity, and repeatability of the analytical method. In this work, amine (NH 2 )-functionalized material of Institute Lavoisier (MIL)-53(Al) nanoparticles were successfully synthesized, characterized, and applied as the SPME fiber coating for efficient sample pretreatment owing to their unique structures and excellent adsorption properties. Under optimized conditions, the NH 2 -MIL-53(Al)-coated fiber showed good precision, low limits of detection (LODs) [0.025-0.83 ng L -1 for synthetic musks (SMs) and 0.051-0.97 ng L -1 for organochlorine pesticides (OCPs)], and good linearity. Experimental results showed that the NH 2 -MIL-53(Al) SPME coating was solvent resistant and thermostable. In addition, the extraction efficiencies of the NH 2 -MIL-53(Al) coating for SMs and OCPs were higher than those of commercially available SPME fiber coatings such as polydimethylsiloxane, polydimethylsiloxane-divinylbenzene, and polyacrylate. The reasons may be that the analytes are adsorbed on NH 2 -MIL-53(Al) primarily through π-π interactions, electron donor-electron acceptor interactions, and hydrogen bonds between the analytes and organic linkers of the material. Direct immersion (DI) SPME-gas chromatography-mass spectrometry methods based on NH 2 -MIL-53(Al) were successfully applied for the analysis of tap and river water samples. The recoveries were 80.3-115% for SMs and 77.4-117% for OCPs. These results indicate that the NH 2 -MIL-53(Al) coating may be a promising alternative to SPME coatings for the enrichment of SMs and OCPs.

pH-activated Nanoparticles for Controlled Topical Delivery of Farnesol to Disrupt Oral Biofilm Virulence

PubMed Central

Horev, Benjamin; Klein, Marlise I.; Hwang, Geelsu; Li, Yong; Kim, Dongyeop; Koo, Hyun; Benoit, Danielle S.W.

2015-01-01

Development of effective therapies to control oral biofilms is challenging, as topically introduced agents must avoid rapid clearance from biofilm-tooth interfaces while targeting biofilm microenvironments. Additionally, exopolysaccharide matrix and acidification of biofilm microenvironments are associated with cariogenic (caries-producing) biofilm virulence. Thus, nanoparticle carriers capable of binding to hydroxyapatite (HA), saliva-coated HA (sHA), and exopolysaccharides with enhanced drug-release at acidic pH were developed. Nanoparticles are formed from diblock copolymers composed of 2-(dimethylamino)ethyl methacrylate (DMAEMA), butyl methacrylate (BMA), and 2-propylacrylic acid (PAA) (p(DMAEMA)-b-p(DMAEMA-co-BMA-co-PAA)) that self-assemble into ~21 nm cationic nanoparticles. Nanoparticles exhibit outstanding adsorption affinities (~244 L-mmol−1) to negatively-charged HA, sHA, and exopolysaccharide-coated sHA due to strong electrostatic interactions via multivalent tertiary amines of p(DMAEMA). Owing to hydrophobic cores, Nanoparticles load farnesol, a hydrophobic antibacterial drug, at ~22 wt%. Farnesol release is pH-dependent with t1/2=7 and 15 h for release at pH 4.5 and 7.2, as Nanoparticles undergo core destabilization at acidic pH, characteristic of cariogenic biofilm microenvironments. Importantly, topical applications of farnesol-loaded nanoparticles disrupted Streptococcus mutans biofilms 4-fold more effectively than free farnesol. Mechanical stability of biofilms treated with drug-loaded nanoparticles was compromised, resulting in >2-fold enhancement in biofilm removal under shear stress compared to free farnesol and controls. Farnesol-loaded nanoparticles effectively attenuated biofilm virulence in vivo using a clinically-relevant topical treatment regimen (2×/day) in a rodent dental caries disease model. Treatment with farnesol-loaded nanoparticles reduced both the number and severity of carious lesions, while free-farnesol had no effect. Nanoparticles have great potential to enhance the efficacy of antibiofilm agents through multi-targeted binding and pH-responsive drug release due to microenvironmental triggers. PMID:25661192

Nanocrystallinity effects on osteoblast and osteoclast response to silicon substituted hydroxyapatite.

PubMed

Casarrubios, Laura; Matesanz, María Concepción; Sánchez-Salcedo, Sandra; Arcos, Daniel; Vallet-Regí, María; Portolés, María Teresa

2016-11-15

Silicon substituted hydroxyapatites (SiHA) are highly crystalline bioceramics treated at high temperatures (about 1200°C) which have been approved for clinical use with spinal, orthopedic, periodontal, oral and craniomaxillofacial applications. The preparation of SiHA with lower temperature methods (about 700°C) provides nanocrystalline SiHA (nano-SiHA) with enhanced bioreactivity due to higher surface area and smaller crystal size. The aim of this study has been to know the nanocrystallinity effects on the response of both osteoblasts and osteoclasts (the two main cell types involved in bone remodelling) to silicon substituted hydroxyapatite. Saos-2 osteoblasts and osteoclast-like cells (differentiated from RAW-264.7 macrophages) have been cultured on the surface of nano-SiHA and SiHA disks and different cell parameters have been evaluated: cell adhesion, proliferation, viability, intracellular content of reactive oxygen species, cell cycle phases, apoptosis, cell morphology, osteoclast-like cell differentiation and resorptive activity. This comparative in vitro study evidences that nanocrystallinity of SiHA affects the cell/biomaterial interface inducing bone cell apoptosis by loss of cell anchorage (anoikis), delaying osteoclast-like cell differentiation and decreasing the resorptive activity of this cell type. These results suggest the potential use of nano-SiHA biomaterial for preventing bone resorption in treatment of osteoporotic bone. Copyright © 2016 Elsevier Inc. All rights reserved.

Mathematical modeling of microbially induced crown corrosion in wastewater collection systems and laboratory investigation and modeling of sulfuric acid corrosion of concrete

NASA Astrophysics Data System (ADS)

Jahani, Fereidoun

In the model for microbially induced crown corrosion, the diffusion of sulfide inside the concrete pores, its biological conversion to sulfuric acid, and the corrosion of calcium carbonate aggregates are represented. The corrosion front is modeled as a moving boundary. The location of the interface between the corrosion layer and the concrete is determined as part of the solution to the model equations. This model consisted of a system of one dimensional reaction-diffusion equations coupled to an equation describing the movement of the corrosion front. The equations were solved numerically using finite element Galerkin approximation. The concentration profiles of sulfide in the air and the liquid phases, the pH as a function of concrete depth, and the position of the corrosion front. A new equation for the corrosion rate was also derived. A more specific model for the degradation of a concrete specimen exposed to a sulfuric acid solution was also studied. In this model, diffusion of hydrogen ions and their reaction with alkaline components of concrete were expressed using Fick's Law of diffusion. The model equations described the moving boundary, the dissolution rate of alkaline components in the concrete, volume increase of sulfuric acid solution over the concrete specimen, and the boundary conditions on the surface of the concrete. An apparatus was designed and experiments were performed to measure pH changes on the surface of concrete. The data were used to calculate the dissolution rate of the concrete and, with the model, to determine the diffusion rate of sulfuric acid in the corrosion layer and corrosion layer thickness. Electrochemical Impedance Spectroscopy (EIS) was used to study the corrosion rate of iron pins embedded in the concrete sample. The open circuit potential (OCP) determined the onset of corrosion on the surface of the pins. Visual observation of the corrosion layer thickness was in good agreement with the simulation results.

Cold Spray Coating of Submicronic Ceramic Particles on Poly(vinyl alcohol) in Dry and Hydrogel States

NASA Astrophysics Data System (ADS)

Moreau, David; Borit, François; Corté, Laurent; Guipont, Vincent

2017-06-01

We report an approach using cold spray technology to coat poly(vinyl alcohol) (PVA) in polymer and hydrogel states with hydroxyapatite (HA). Using porous aggregated HA powder, we hypothesized that fragmentation of the powder upon cold spray could lead to formation of a ceramic coating on the surface of the PVA substrate. However, direct spraying of this powder led to complete destruction of the swollen PVA hydrogel substrate. As an alternative, HA coatings were successfully produced by spraying onto dry PVA substrates prior to swelling in water. Dense homogeneous HA coatings composed of submicron particles were obtained using rather low-energy spraying parameters (temperature 200-250 °C, pressure 1-3 MPa). Coated PVA substrates could swell in water without removal of the ceramic layer to form HA-coated hydrogels. Microscopic observations and in situ measurements were used to explain how local heating and impact of sprayed aggregates induced surface roughening and strong binding of HA particles to the molten PVA substrate. Such an approach could lead to design of ceramic coatings whose roughness and crystallinity can be finely adjusted to improve interfacing with biological tissues.

Effects of Coulomb Coupling on the Stopping Power of Plasmas

NASA Astrophysics Data System (ADS)

Bernstein, David; Daligault, Jerome; Baalrud, Scott

2017-10-01

Stopping power of charged particles in plasma is important for a detailed understanding of particle and energy transport in plasmas, such as those found in fusion applications. Although stopping power is rather well understood for weakly coupled plasmas, this is less the case for strongly coupled plasmas. In order to shed light on the effects of strong Coulomb coupling, we have conducted detailed molecular dynamics simulations of the stopping power of a One-Component Plasma (OCP) across a wide range of conditions. The OCP allows first-principle computations that are not possible with more complex models, enabling rigorous tests of analytical theories. The molecular dynamics simulations were compared to two analytical theories that attempt to extend traditional weakly-coupled theories into the strong coupling regime. The first is based on the binary approximation, which accounts for strong coupling via an effective scattering cross section derived from the effective potential theory. The second is based on the dielectric function formulation with the inclusion of a local field corrections. Work supported by LANL LDRD project 20150520ER and ir Force Office of Scientific Research under Award Number FA9550-16-1-0221.

Investigations of the structure and "interfacial" surface chemistry of Bioglass (RTM) materials by solid-state multinuclear NMR spectroscopy

NASA Astrophysics Data System (ADS)

Sarkar, Gautam

Bioactive materials such as BioglassRTM 45S5 (45% SiO 2, 24.5% CaO, 24.5% Na2O, and 6% P2O5 by weight) are sodium-phosphosilicate glasses containing independent three-dimensional silicate and phosphate networks and Na+ and Ca2+ ions as modifying cations. Due to their bioactivity, these materials are currently used as implants and for other surgical and clinical applications. The bioactivity of BioglassesRTM is due to their unique capability to form chemical bonds to tissues through an octacalciumphosphate (OCP)- and/or hydroxyapatite-like (HA) "interfacial" matrix. The formation of OCP and/or HA is preceded by the formation of a silica-rich surface layer and the subsequent growth of an amorphous calcium phosphate (a-CP) layer. Structural characterization of a series of commercial and synthesized Bioglass materials 45S5 52S, 55S, 60S, and synthesized 17O-labelled "Bioglass materials 45S, 52S, 55S and 60S" have been obtained using solid-state single-pulse magic-angle spinning (SP/MAS) 17O, 23Na, 29Si and 31P NMR. The 17O NMR isotropic chemical shifts and estimates of the quadrupole coupling constants (Cq) [at fixed asymmetry parameter ( hQ ) values of zero] have been obtained from solid-state spin-echo 17O SP/MAS NMR spectra of 17O-labelled "Bioglasses". The simulation results of these spectra reveal the presence of both bridging-oxygens (BO, i.e. ≡ Si-17OSi ≡ ) and non-bridging oxygens (NBO, i.e. ≡ Si-17O-Na+/Ca2+ ) in the silicate networks in these materials. 17O NMR spectra of these Bioglass materials do not show any direct evidence for the presence of BO and NBO atoms in the phosphate units; however, they are expected to be present in small amounts. In vitro reactions of BioglassRTM 45S5, 60S and 77S powders have been used to study the "interfacial" surface chemistry of these materials in simulated body-fluid (SBF, Kyoto or K9 solution) and/or 17O-enriched tris-buffer solution. 29Si and 31P SP/MAS NMR have been used to identify and quantify the extent of formation of surface silica species and follow the formation of phosphate species, respectively, while cross-polarization magic-angle spinning (CP/MAS) 29Si and 31P NMR have provided information about low intensity NMR peaks due to various silicon- and phosphorus-species present in the vicinity of associated protons on the surface of in vitro reacted BioglassRTM materials. The solid-state NMR investigations of the "interfacial" surface reactions of BioglassRTM materials are discussed in the context of the structure of these materials and the influence of this structure on the kinetics and the mechanism of their "interfacial" surface chemistry. (Abstract shortened by UMI.) BioglassRTM, trademark, University of Florida, Gainesville, FL, 32611.

Plasma convection and ion beam generation in the plasma sheet boundary layer

NASA Technical Reports Server (NTRS)

Moghaddam-Taaheri, E.; Goertz, C. K.; Smith, R. A.

1991-01-01

Because of the dawn-dusk electric field E(dd), plasma in the magnetotail convects from the lobe toward the central plasma sheet (CPS). In the absence of space or velocity diffusion due to plasma turbulence, convection would yield a steady state distribution function f = V exp (-2/3) g(v exp 2 V exp 2/3), where V is the flux tube volume. Starting with such a distribution function and a plasma beta which varies from beta greater than 1 in the CPS to beta much smaller than 1 in the lobe, the evolution of the ion distribution function was studied considering the combined effects of ion diffusion by kinetic Alfven waves (KAW) in the ULF frequency range (1-10 mHz) and convection due to E(dd) x B drift in the plasma sheet boundary layer (PSBL) and outer central plasma sheet (OCPS). The results show that, during the early stages after launching the KAWs, a beamlike ion distribution forms in the PSBL and at the same time the plasma density and temperature decrease in the OCPS. Following this stage, ions in the beams convect toward the CPS resulting in an increase of the plasma temperature in the OCPS.

Organochlorine pesticide level in patients with chronic kidney disease of unknown etiology and its association with renal function.

PubMed

Ghosh, Rishila; Siddarth, Manushi; Singh, Neeru; Tyagi, Vipin; Kare, Pawan Kumar; Banerjee, Basu Dev; Kalra, Om Prakash; Tripathi, Ashok Kumar

2017-05-26

Involvement of agrochemicals have been suggested in the development of chronic kidney disease of unknown etiology (CKDu). The association between CKDu and blood level of organochlorine pesticides (OCPs) in CKDu patients has been examined in the present study. All the recruited study subjects (n = 300) were divided in three groups, namely, healthy control (n = 100), patients with chronic kidney disease of unknown etiology (n = 100), and patients with chronic kidney disease of known etiology (CKDk) (n = 100). Blood OCP levels of all three study groups were analyzed by gas chromatography. Increased level of OCPs, namely α-HCH, aldrin, and β-endosulfan, were observed in CKDu patients as compared to healthy control and CKD patients of known etiology. The levels of these pesticides significantly correlated negatively with the estimated glomerular filtration rate (eGFR) and positively with urinary albumin of CKD patients. Logistic regression analysis revealed association of γ-HCH, p, p'-DDE, and β-endosulfan with CKDu on adjustment of age, sex, BMI, and total lipid content. Increased blood level of certain organochlorine pesticides is associated with the development of chronic kidney disease of unknown etiology.

Organochlorine and organophosphorus pesticide residues in fodder and milk samples along Musi river belt, India.

PubMed

Kotinagu, Korrapati; Krishnaiah, Nelapati

2015-04-01

The present study was conducted to find the organochlorine pesticide (OCP) and organophosphorus pesticide (OPP) residues in fodder and milk samples along Musi river belt, India. Fodder and milk samples collected from the six zones of Musi river belt, Hyderabad India were analyzed by gas chromatography with electron capture detector for OCP residues and pulsated flame photometric detector for the presence of OPP residues. The gas chromatographic analysis of fodder samples of Zone 5 of Musi river showed the residues of dicofol at concentration of 0.07±0.0007 (0.071-0.077). Among organophosphorus compounds, dimetheoate was present in milk samples collected from Zone 6 at a level of 0.13±0.006 (0.111-0.167). The residues of OCPs, OPPs and cyclodies were below the detection limit in the remaining fodder and milk samples collected from Musi river belt in the present study. The results indicate that the pesticide residues in fodder and milk samples were well below the maximum residue level (MRL) values, whereas dicofol in fodder and dimethoate in milk were slightly above the MRL values specified by EU and CODEX.

Organochlorine and organophosphorus pesticide residues in fodder and milk samples along Musi river belt, India

PubMed Central

Kotinagu, Korrapati; Krishnaiah, Nelapati

2015-01-01

Aim: The present study was conducted to find the organochlorine pesticide (OCP) and organophosphorus pesticide (OPP) residues in fodder and milk samples along Musi river belt, India. Materials and Methods: Fodder and milk samples collected from the six zones of Musi river belt, Hyderabad India were analyzed by gas chromatography with electron capture detector for OCP residues and pulsated flame photometric detector for the presence of OPP residues. Results: The gas chromatographic analysis of fodder samples of Zone 5 of Musi river showed the residues of dicofol at concentration of 0.07±0.0007 (0.071-0.077). Among organophosphorus compounds, dimetheoate was present in milk samples collected from Zone 6 at a level of 0.13±0.006 (0.111-0.167). The residues of OCPs, OPPs and cyclodies were below the detection limit in the remaining fodder and milk samples collected from Musi river belt in the present study. Conclusion: The results indicate that the pesticide residues in fodder and milk samples were well below the maximum residue level (MRL) values, whereas dicofol in fodder and dimethoate in milk were slightly above the MRL values specified by EU and CODEX. PMID:27047132

Altitudinal and chiral signature of persistent organochlorine pesticides in air, soil, and spruce needles (Picea abies) of the Alps.

PubMed

Shen, Heqing; Henkelmann, Bernhard; Levy, Walkiria; Zsolnay, Adam; Weiss, Peter; Jakobi, Gert; Kirchner, Manfred; Moche, Wolfgang; Braun, Katharina; Schramm, Karl-Werner

2009-04-01

The present study investigated the distribution, transportation, and biodegradation of the selected chiral persistent organochlorine pesticides (OCP) in the Alps. In the complex environment, we found the movement and fate of OCP could be defined by many factors. Taking HCE as an example, below the timberline its accumulation from air into SPMD increased with altitude and seasonally changed, but the trends reversed above the timberline. In soil, the tendency of HCE concentrations vs organic materials followed a sigmoid curve, and HCE concentration-altitude correlations are positive in central Alps but negative in southern Alps. The HCE enantiomeric ratios (ERs) in soil correlated to HCE isomers concentrations, the humus pH values, and the sampling site altitudes. HCE shift from humus to mineral soil can also be traced by ERs. The altitudinal and longitudinal trends in needles suggested that alpha-HCH has a more complex movementthan HCE in Alps. In conclusion, altitude conducted condensation, plant canopies, organic material in soil, and geographic specific precipitations may affect OCP distributions and transportation, whereas altitude conducted temperature and soil pH could dictate their fate in the environment.

Organochlorine pesticide residues in strawberries from integrated pest management and organic farming.

PubMed

Fernandes, Virginia C; Domingues, Valentina F; Mateus, Nuno; Delerue-Matos, Cristina

2011-07-27

A rapid, specific, and sensitive method based on the Quick Easy Cheap Effective Rugged and Safe (QuEChERS) method and a cleanup using dispersive solid-phase extraction with MgSO(4), PSA, and C18 sorbents has been developed for the routine analysis of 14 pesticides in strawberries. The analyses were performed by three different analytical methodologies: gas chromatography (GC) with electron capture detection (ECD), mass spectrometry (MS), and tandem mass spectrometry (MS/MS). The recoveries for all the pesticides studied were from 46 to 128%, with relative standard deviation of <15% in the concentration range of 0.005-0.250 mg/kg. The limit of detection (LOD) for all compounds met maximum residue limits (MRL) accepted in Portugal for organochlorine pesticides (OCP). A survey study of strawberries produced in Portugal in the years 2009-2010 obtained from organic farming (OF) and integrated pest management (IPM) was developed. Lindane and β-endosulfan were detected above the MRL in OF and IPM. Other OCP (aldrin, o,p'-DDT and their metabolites, and methoxychlor) were found below the MRL. The OCP residues detected decreased from 2009 to 2010. The QuEChERS method was successfully applied to the analysis of strawberry samples.

Research on torsional friction behavior and fluid load support of PVA/HA composite hydrogel.

PubMed

Chen, Kai; Zhang, Dekun; Yang, Xuehui; Cui, Xiaotong; Zhang, Xin; Wang, Qingliang

2016-09-01

Hydrogels have been extensively studied for use as synthetic articular cartilage. This study aimed to investigate (1) the torsional friction contact state and the transformation mechanism of PVA/HA composite hydrogel against CoCrMo femoral head and (2) effects of load and torsional angle on torsional friction behavior. The finite element method was used to study fluid load support of PVA/HA composite hydrogel. Results show fluid loss increases gradually of PVA/HA composite hydrogel with torsional friction time, leading to fluid load support decreases. The contact state changes from full slip state to stick-slip mixed state. As the load increases, friction coefficient and adhesion zone increase gradually. As the torsional angle increases, friction coefficient and slip trend of the contact interface increase, resulting in the increase of the slip zone and the reduction of the adhesion zone. Fluid loss increases of PVA/HA composite hydrogel as the load and the torsional angle increase, which causes the decrease of fluid load support and the increase of friction coefficient. Copyright © 2016 Elsevier Ltd. All rights reserved.

Knowledge and utilization of the partograph: A cross-sectional survey among obstetric care providers in urban referral public health institutions in northwest and southwest Cameroon.

PubMed

Sama, Carlson-Babila; Takah, Noah F; Danwe, Valery K; Melo, Uzeru Forchu; Dingana, Therence Nwana; Angwafo, Fru F

2017-01-01

The enormous challenge to maternal well-being with associated maternal wastages during labour has remained an unsurmountable problem in Cameroon which reflects the current high maternal mortality rate. Evidence abounds that cost-effective and affordable health interventions like the use of the partograph will contribute to curb the alarming number of intrapartum maternal deaths. However, little is known about the level of knowledge and utilization of this simple life-saving tool in the North-and South-West Regions, Cameroon. Using a self-administered structured questionnaire, a cross-sectional study was conducted from January 4th-March 25th 2016 among non-physician obstetric care providers (OCPs) across urban public health institutions in these regions. Logistic regression models were used to identify factors associated with good knowledge and routine utilization of the partograph. Of the 79 eligible participants, 71 (89.9%) took part in the study. The mean age of the respondents was 37.9±10.0 years with majority being female (85.9%). Less than one-third (29.6%) of the respondents had good knowledge on the partograph and only 23 (32.4%) routinely used it in monitoring labour. OCPs working in Maternal and Infant Welfare Clinics were about 4 times more likely than those working in Regional/District Hospitals to have good knowledge on the partograph [AOR = 3.88 (95% CI:1.07-14.04)], p = 0.04. Little or no knowledge of the partograph and poor staff strength in the study centres were factors militating against its routine use. The knowledge and use of the partograph in this study is sub-optimal. Regular in-service training of OCPs superimposed with periodic workshops and seminars, provision of reasonable staff numbers, and mandatory institutional policies on routine use of the partograph are recommended as vital first steps towards ensuring the safety of women in labour in the North-and South-West Regions of Cameroon.

Organochlorine pesticides levels and associated factors in a group of blood donors in São Paulo, Brazil.

PubMed

do Nascimento, Felipe Parra; Kuno, Rúbia; Lemes, Vera Regina Rossi; Kussumi, Tereza Atsuko; Nakano, Viviane Emi; Rocha, Sonia Bio; de Oliveira, Maria Celeste Cardeal; de Albuquerque Kimura, Iracema; Gouveia, Nelson

2017-08-01

The use of organochlorine pesticides (OCPs) is a worldwide public health concern given that high levels of these compounds in humans and animals can lead to serious health problems. This study aimed to evaluate the levels of 15 organochlorine pesticides in the serum of 547 blood donors in the São Paulo metropolitan region (SPMR) in 2009 and to investigate factors associated with higher levels of these compounds. The OCPs were determined by gas chromatography with micro electron capture detection. Multiple ordinal logistic regression models were employed to determine the factors associated with higher levels. Only β-HCH and p,p'-DDE had a significant number of samples above the limit of quantification. Factors associated with higher levels of β-HCH were age within 26 to 35 years (OR = 3.1 [1.05-9.09]), age within 36 to 45 years (OR = 18.27 [6.89-48.91]), and female gender (OR = 0.44 [0.24-0.82] for men). p,p'-DDE levels were associated with age within 26 to 35 years (OR = 2.65 [1.20-3.45]), age within 36 to 45 years (OR = 4.59 [2.64-7.92]), female gender (OR = 0.86 [0.43-0.94] for men), and previous work with pesticides (OR = 2.88 [1.22-6.84]). Lower levels of p,p'-DDE were associated with an income of 3 to 5 minimum wages (OR = 0.38 [0.19-0.75]) and with intake of foods from animal origin up to twice a week (OR = 0.15 [0.03-0.72]) and more than twice a week (OR = 0.10 [0.02-0.47]). The results of this study indicate that the study group was not exposed to high levels of OCPs.

Weight Loss and Lowering Androgens Predict Improvements in Health-Related Quality of Life in Women With PCOS

PubMed Central

Sarwer, David B.; Allison, Kelly C.; Milman, Lauren; Kris-Etherton, Penny M.; Kunselman, Allen R.; Stetter, Christy M.; Williams, Nancy I.; Gnatuk, Carol L.; Estes, Stephanie J.; Fleming, Jennifer; Coutifaris, Christos; Legro, Richard S.

2016-01-01

Context: Polycystic ovary syndrome (PCOS) is associated with reduced health-related quality of life (HRQOL) and increased prevalence of depressive and anxiety disorders. The impact of PCOS-specific treatments on these co-morbidities is unclear. Objective: To assess the impact of weight loss and decreasing hyperandrogenism on HRQOL and mood and anxiety disorders in women with PCOS. Design/Setting/Participants: A secondary analysis of a randomized controlled trial (OWL-PCOS) of preconception treatment conducted at two academic centers in women (age, 18–40 years; body mass index, 27–42 kg/m2) with PCOS defined by Rotterdam criteria. Intervention: Continuous oral contraceptive pill (OCP) or intensive lifestyle intervention or the combination (Combined) for 16 weeks. Main Outcome Measure(s): Changes in HRQOL assessed by PCOSQ and SF-36 and prevalence of depression and anxiety disorder assessed by PRIME-MD PHQ. Results: The lowest scores were noted on the general health domain of the SF-36 and the weight and infertility domains on the PCOSQ. All three interventions resulted in significant improvement in the general health score on the SF-36. Both the OCP and Combined groups showed improvements in all domains of the PCOSQ (P < .01) compared to baseline scores. The Combined group had significant improvements in the weight, body hair, and infertility domains compared to a single treatment group (P < .05). In a linear regression model, change in weight correlated with improvements in the weight domain (P < .001) and physical well-being (P < .02), change in T correlated with improvements in the hair domain (P < .001), and change in both weight and T correlated with the infertility (P < .001) and menstrual domains (P < .05). Conclusions: Both weight loss and OCP use result in significant improvements in several physical and mental domains related to quality of life, depressive symptoms, and anxiety disorders, and combined therapies offer further benefits in overweight/obese women with PCOS. PMID:27253669

Weight Loss and Lowering Androgens Predict Improvements in Health-Related Quality of Life in Women With PCOS.

PubMed

Dokras, Anuja; Sarwer, David B; Allison, Kelly C; Milman, Lauren; Kris-Etherton, Penny M; Kunselman, Allen R; Stetter, Christy M; Williams, Nancy I; Gnatuk, Carol L; Estes, Stephanie J; Fleming, Jennifer; Coutifaris, Christos; Legro, Richard S

2016-08-01

Polycystic ovary syndrome (PCOS) is associated with reduced health-related quality of life (HRQOL) and increased prevalence of depressive and anxiety disorders. The impact of PCOS-specific treatments on these co-morbidities is unclear. To assess the impact of weight loss and decreasing hyperandrogenism on HRQOL and mood and anxiety disorders in women with PCOS. A secondary analysis of a randomized controlled trial (OWL-PCOS) of preconception treatment conducted at two academic centers in women (age, 18-40 years; body mass index, 27-42 kg/m(2)) with PCOS defined by Rotterdam criteria. Continuous oral contraceptive pill (OCP) or intensive lifestyle intervention or the combination (Combined) for 16 weeks. Changes in HRQOL assessed by PCOSQ and SF-36 and prevalence of depression and anxiety disorder assessed by PRIME-MD PHQ. The lowest scores were noted on the general health domain of the SF-36 and the weight and infertility domains on the PCOSQ. All three interventions resulted in significant improvement in the general health score on the SF-36. Both the OCP and Combined groups showed improvements in all domains of the PCOSQ (P < .01) compared to baseline scores. The Combined group had significant improvements in the weight, body hair, and infertility domains compared to a single treatment group (P < .05). In a linear regression model, change in weight correlated with improvements in the weight domain (P < .001) and physical well-being (P < .02), change in T correlated with improvements in the hair domain (P < .001), and change in both weight and T correlated with the infertility (P < .001) and menstrual domains (P < .05). Both weight loss and OCP use result in significant improvements in several physical and mental domains related to quality of life, depressive symptoms, and anxiety disorders, and combined therapies offer further benefits in overweight/obese women with PCOS.

Effect of Self-etch Adhesives on Self-sealing Ability of High-Copper Amalgams

PubMed Central

Moazzami, Saied Mostafa; Moosavi, Horieh; Moddaber, Maryam; Parvizi, Reza; Moayed, Mohamad Hadi; Mokhber, Nima; Meharry, Michael; B Kazemi, Reza

2016-01-01

Statement of the Problem: Similar to conventional amalgam, high-copper amalgam alloy may also undergo corrosion, but it takes longer time for the resulting products to reduce microleakage by sealing the micro-gap at the tooth/amalgam interface. Purpose: The aim of this study was to evaluate the effect of self-etch adhesives with different pH levels on the interfacial corrosion behavior of high-copper amalgam restoration and its induction potential for self-sealing ability of the micro-gap in the early hours after setting by means of Electro-Chemical Tests (ECTs). Materials and Method: Thirty cylindrical cavities of 4.5mm x 4.7mm were prepared on intact bicuspids. The samples were divided into five main groups of application of Adhesive Resin (AR)/ liner/ None (No), on the cavity floor. The first main group was left without an AR/ liner (No). In the other main groups, the types of AR/ liner used were I-Bond (IB), Clearfil S3 (S3), Single Bond (SB) and Varnish (V). Each main group (n=6) was divided into two subgroups (n=3) according to the types of the amalgams used, either admixed ANA 2000 (ANA) or spherical Tytin (Tyt). The ECTs, Open Circuit Potential (OCP), and the Linear Polarization Resistance (LPR) for each sample were performed and measured 48 hours after the completion of the samples. Results: The Tyt-No and Tyt-IB samples showed the highest and lowest OCP values respectively. In LPR tests, the Rp values of ANA-V and Tyt-V were the highest (lowest corrosion rate) and contrarily, the ANA-IB and Tyt-IB samples, with the lowest pH levels, represented the lowest Rp values (highest corrosion rates). Conclusion: Some self-etch adhesives may increase interfacial corrosion potential and self-sealing ability of high-copper amalgams. PMID:27942548

Polychlorinated biphenyls and organochlorinated pesticides in birds from a contaminated region in South China: association with trophic level, tissue distribution and risk assessment.

PubMed

Zhang, Xiu-Lan; Luo, Xiao-Jun; Liu, Juan; Luo, Yong; Chen, She-Jun; Mai, Bi-Xian

2011-05-01

Birds have been used successfully for biomonitoring of the levels and effects of persistent organic pollutants (POPs) in the environments; however, there is exceedingly little data on organochlorinated pesticide (OCPs) and polychlorinated biphenyls (PCBs) residues in bird inhabiting in China. In the present study, we detected the concentrations of PCBs, dichlorodiphenyltrichloroethane and its metabolites (DDTs) and hexachlorocyclohexanes (HCHs) in muscle, liver and kidney of birds that inhabit in an e-waste recycling site. Associated with the stable isotope ratio (δ (15)N), we investigated the effect of trophic level on the body burdens of persistent contaminants in birds. The tissue distributions of contaminants in these birds were examined, and a preliminary risk assessment was also conducted. Specimens from eight bird species were collected from Qingyuan County, Guangdong Province, South China. Pectoral muscle, liver and kidney tissues were Soxhlet-extracted and finally dissolved in isooctane. Both PCBs and OCPs were analyzed by gas chromatography-mass spectrometry. The subsamples for nitrogen stable isotope analysis were lyophilized, ground and analyzed by a flash EA 112 series elemental analyzer interfaced with an isotope ration mass spectrometer. PCBs exhibited the highest concentrations among all target compounds, and a preliminary risk assessment suggested that adverse effects might occur in some birds for its high level. Generally, the concentrations of pollutants in liver and kidney were higher than those in muscle, which was mainly driven by passive diffusion to the 'lipid-compartment'. Significant differences in level of contaminants were obtained among species due to the varieties in dietary composition and habitat. An increasing trend was obtained between concentrations of PCBs and DDTs with trophic levels; however, HCHs exhibited the same level among species. Because of the e-waste recycling activities, the study area has been heavily polluted by PCBs. Studies on the species-specific hazard assessment associated with exposure to PCBs are urgently needed in the study of birds in the area.

AIRMICS (U.S. Army Institute for Research in Management Information, Communications and Computer Sciences) Information Center Model Site Evaluation

DTIC Science & Technology

1986-10-01

34 syndrome . Five techniques for developing user self-sufficiency were discussed in-depth: (1) provide training at different proficiency levels, id provide...WY aba. 4 ’-a ’aba. @9 "a,.. I bJ~ V N- S ha. E-ii S ’a ’baa .4, .;y ’. ; . a.,. ~ ~ .: ;r YK’.- xYY I. r d’...da.4/ 4/ tq..ttf.%r./..v-./ - "cc~’ v,-r...data base, accessible through a user friendly interfaces, to correlate and deliver crime , traffic, vehicle, and personnel information to " / fixed and

Bond strength determination of hydroxyapatite coatings on Ti-6Al-4V substrates using the LAser Shock Adhesion Test (LASAT).

PubMed

Guipont, Vincent; Jeandin, Michel; Bansard, Sebastien; Khor, Khiam Aik; Nivard, Mariette; Berthe, Laurent; Cuq-Lelandais, Jean-Paul; Boustie, Michel

2010-12-15

An adhesion test procedure applied to plasma-sprayed hydroxyapatite (HA) coatings to measure the "LASAT threshold" (LAser Shock Adhesion test) is described. The good repeatability and minimal discrepancy of the laser-driven adhesion test data were ascertained for conventional plasma sprayed HA coatings. As a further demonstration, the procedure was applied to HA coatings with diverse characteristics on the ceramic/metal interface. Different preheating and grit blasting conditions and the presence of a thick plasma-sprayed Ti sublayer or a thin TiO(2) layer prepared by oxidation were investigated through LASAT. It was assessed that a rough surface can significantly improve the coating's bond strength. However, it was also demonstrated that a thin TiO(2) layer on a smooth Ti-6Al-4V substrate can have a major influence on adhesion as well. Preheating up to 270°C just prior to the first HA spraying pass had no effect on the adhesion strength. Further development of the procedure was done to achieve an in situ LASAT with in vitro conditions applied on HA coatings. To that end, different crystalline HA contents were soaked in simulated body fluid (SBF). Beyond the demonstration of the capability of this laser-driven adhesion test devoted to HA coatings in dry or liquid environment, the present study provided empirical information on pertinent processing characteristics that could strengthen or weaken the HA/Ti-6Al-4V bond. Copyright © 2010 Wiley Periodicals, Inc.

Hydroxyapatite-coated magnesium implants with improved in vitro and in vivo biocorrosion, biocompatibility, and bone response.

PubMed

Kim, Sae-Mi; Jo, Ji-Hoon; Lee, Sung-Mi; Kang, Min-Ho; Kim, Hyoun-Ee; Estrin, Yuri; Lee, Jong-Ho; Lee, Jung-Woo; Koh, Young-Hag

2014-02-01

Magnesium and its alloys are candidate materials for biodegradable implants; however, excessively rapid corrosion behavior restricts their practical uses in biological systems. For such applications, surface modification is essential, and the use of anticorrosion coatings is considered as a promising avenue. In this study, we coated Mg with hydroxyapatite (HA) in an aqueous solution containing calcium and phosphate sources to improve its in vitro and in vivo biocorrosion resistance, biocompatibility and bone response. A layer of needle-shaped HA crystals was created uniformly on the Mg substrate even when the Mg sample had a complex shape of a screw. In addition, a dense HA-stratum between this layer and the Mg substrate was formed. This HA-coating layer remarkably reduced the corrosion rate of the Mg tested in a simulated body fluid. Moreover, the biological response, including cell attachment, proliferation and differentiation, of the HA-coated samples was enhanced considerably compared to samples without a coating layer. The preliminary in vivo experiments also showed that the biocorrosion of the Mg implant was significantly retarded by HA coating, which resulted in good mechanical stability. In addition, in the case of the HA-coated implants, biodegradation was mitigated, particularly over the first 6 weeks of implantation. This considerably promoted bone growth at the interface between the implant and bone. These results confirmed that HA-coated Mg is a promising material for biomedical implant applications. © 2013 Wiley Periodicals, Inc.

In vitro performance of Ag-incorporated hydroxyapatite and its adhesive porous coatings deposited by electrostatic spraying.

PubMed

Gokcekaya, Ozkan; Webster, Thomas J; Ueda, Kyosuke; Narushima, Takayuki; Ergun, Celaletdin

2017-08-01

Bacterial infection of implanted materials is a significant complication that might require additional surgical operations for implant retrieval. As an antibacterial biomaterial, Ag-containing hydroxyapatite (HA) may be a solution to reduce the incidences of implant associated infections. In this study, pure, 0.2mol% and 0.3mol% Ag incorporated HA powders were synthesized via a precipitation method. Colloidal precursor dispersions prepared from these powders were used to deposit porous coatings onto titanium and stainless steel substrates via electrostatic spraying. The porous coating layers obtained with various deposition times and heat treatment conditions were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Scratch tests were conducted to assess the adhesion strength of the coating. Antibacterial activity of Ag-incorporated HA was tested towards Escherichia coli (E. coli) at various incubation times. Osteoblast adhesion on Ag-incorporated HA was evaluated to assess biocompatibility. Improvement in adhesion strength of the coating layer was observed after the heat treatment process due to mutual ionic diffusion at the interface. The Ag-incorporated HA killed all viable E. coli after 24h of incubation, whereas no antibacterial activity was detected with pure HA. In addition, in vitro cell culture tests demonstrated osteoblast adhesion similar to pure HA, which indicated good cytocompatibility. In summary, results of this study provided significant promise for the future study of Ag-incorporated HA for numerous medical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Biocompatibility assessment of graphene oxide-hydroxyapatite coating applied on TiO2 nanotubes by ultrasound-assisted pulse electrodeposition.

PubMed

Fathyunes, Leila; Khalil-Allafi, Jafar; Sheykholeslami, Seyed Omid Reza; Moosavifar, Maryam

2018-06-01

In this study, the ultrasound-assisted pulse electrodeposition was introduced to fabricate the graphene oxide (GO)-hydroxyapatite (HA) coating on TiO 2 nanotubes. The results of the X-ray diffraction (XRD), Fourier Transform Infrared spectroscope (FTIR), Transmission Electron Microscope (TEM) and micro-Raman spectroscopy showed the successful synthesis of GO. The Scanning Electron Microscope (SEM) images revealed that in the presence of ultrasonic waves and GO sheets a more compact HA-based coating with refined microstructure could be formed on the pretreated titanium. The results of micro-Raman analysis confirmed the successful incorporation of the reinforcement filler of GO into the coating electrodeposited by the ultrasound-assisted method. The FTIR analysis showed that the GO-HA coating was consisted predominantly of the B-type carbonated HA (CHA) phase. The pretreatment of the substrate and incorporation of the GO sheets into the HA coating had a significant effect on improving the bonding strength at the coating-substrate interface. Moreover, the results of the fibroblast cell culture and 3‑(4,5‑dimethylthiazolyl‑2)‑2, 5‑diphenyltetrazolium bromide (MTT) assay after 2 days demonstrated a higher percentage of cell activity for the GO-HA coated sample. Finally, the 7-day exposure to simulated body fluid (SBF) showed a faster rate of apatite precipitation on the GO-HA coating, as compared to the HA coating and pretreated titanium. Copyright © 2018 Elsevier B.V. All rights reserved.

Characterization of New PEEK/HA Composites with 3D HA Network Fabricated by Extrusion Freeforming.

PubMed

Vaezi, Mohammad; Black, Cameron; Gibbs, David M R; Oreffo, Richard O C; Brady, Mark; Moshrefi-Torbati, Mohamed; Yang, Shoufeng

2016-05-26

Addition of bioactive materials such as calcium phosphates or Bioglass, and incorporation of porosity into polyetheretherketone (PEEK) has been identified as an effective approach to improve bone-implant interfaces and osseointegration of PEEK-based devices. In this paper, a novel production technique based on the extrusion freeforming method is proposed that yields a bioactive PEEK/hydroxyapatite (PEEK/HA) composite with a unique configuration in which the bioactive phase (i.e., HA) distribution is computer-controlled within a PEEK matrix. The 100% interconnectivity of the HA network in the biocomposite confers an advantage over alternative forms of other microstructural configurations. Moreover, the technique can be employed to produce porous PEEK structures with controlled pore size and distribution, facilitating greater cellular infiltration and biological integration of PEEK composites within patient tissue. The results of unconfined, uniaxial compressive tests on these new PEEK/HA biocomposites with 40% HA under both static and cyclic mode were promising, showing the composites possess yield and compressive strength within the range of human cortical bone suitable for load bearing applications. In addition, preliminary evidence supporting initial biological safety of the new technique developed is demonstrated in this paper. Sufficient cell attachment, sustained viability in contact with the sample over a seven-day period, evidence of cell bridging and matrix deposition all confirmed excellent biocompatibility.

Influence of humic acid on the removal of arsenate and arsenic by ferric chloride: effects of pH, As/Fe ratio, initial As concentration, and co-existing solutes.

PubMed

Kong, Yanli; Kang, Jing; Shen, Jimin; Chen, Zhonglin; Fan, Leitao

2017-01-01

The influence of humic acid (HA) on the removal of arsenic by FeCl 3 was systematically studied in this paper. Jar tests were performed to investigate the influence on arsenic during FeCl 3 coagulation of the pH adjusting method, the initial As/Fe ratio, the equilibrium As concentration, and co-occurring anions and cations. Compared with results in HA-free systems, the removal trends of arsenic in HA solutions were quite different. It was found that As(V) removal was higher at low equilibrium concentration, yet the opposite was true for As(III) removal. The presence of HA influenced the effective number of active sites for arsenic removal by FeCl 3 flocculation. In addition, in the presence of HA, the impacts of co-existing solutions on arsenic removal were also different from that of an HA-free system. This study examined the influence of co-occurring anions, such as phosphate, sulfate, and silicate on arsenic removal, depending on their ability to compete for sorption sites and to hinder or facilitate the aggregation of ferric hydroxide flocs. The presence of Ca 2+ or Cd 2+ significantly increased arsenic removal at higher pH. Low concentrations of dissolved HA and high concentrations of colloid affected the adsorption of arsenic onto iron oxide. The influence of HA on the adsorption of arsenic onto iron oxide primarily depended on the relative content of the dissolved and mineral combination states of HA and the interface combination forms.

Microleakage under orthodontic bands cemented with nano-hydroxyapatite-modified glass ionomer.

PubMed

Enan, Enas T; Hammad, Shaza M

2013-11-01

To estimate the in vivo effect of nano-hydroxyapatite (HA) modification of banding glass-ionomer cement on microleakage under orthodontic bands. Eighty noncarious premolars scheduled for extraction in 20 orthodontic patients were randomly divided into four groups. Grouping was based on the ratio of nano-HA (0%, 5%, 10%, 15% by weight) added to the luting glass-ionomer cement (GIC) Ketac-Cem, which was used for cementation of prefabricated micro-etched orthodontic bands. Dye penetration method was used for microleakage evaluation at the cement-band and cement-enamel interfaces. Statistical evaluation was performed with a Kruskal-Wallis test and a Mann-Whitney U-test, and a Bonferroni-adjusted significance level was calculated. Bands cemented with conventional GIC showed the highest microleakage scores in comparison to those cemented with nano-HA-modified GIC. No significant difference was found between teeth banded with 10% and 15% modified GIC. Modification of the banding GIC with 15% nano-HA revealed a positive effect on reducing microleakage around orthodontic bands.

[Characteristics of hydroxyapatite/PMMA nanocomposites for provisional restoration and its biocompatibility with human gingival fibroblasts].

PubMed

Zhang, Jing-chao; Mo, An-chun; Li, Ji-dong; Wang, Xue-jiang; Li, Yu-bao

2014-05-01

To formulate hydroxyapatite (HA)/polymethyl methacrylate (PMMA) composites with improved cytocompatibility for provisional restoration. Nanocomposites with 20 wt%, 30 wt%, 40 wt%, and 50 wt% HA/PMMA (H/P) were developed and examined using X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). Human gingival fibroblasts were cultured on those HA/PMMA discs and investigated by fluorescent staining on 24 h and MTT assay at 1 d, 3 d, 5 d and 7 d. Chemical integration of HA/PMMA interface was confirmed by XPS. Typical fusiform cells with adhesion spots were detected on 40 wt% and 50 wt% H/P discs. MTT results showed insignificant differences in cell growth between 40 wt% H/P and pure titanium (Ti, P > 0.05), while the other H/P discs showed significantly lower cell growth than pure Ti (P < 0.05). 40 wt% H/P might be a promising candidate for provisional dental implant restoration and for esthetic gingival contour.

Influence of deposition temperature on mechanical properties of plasma-sprayed hydroxyapatite coating on titanium alloy with ZrO2 intermediate layer

NASA Astrophysics Data System (ADS)

Chou, Bang-Yen; Chang, Edward

2003-06-01

Hydroxyapatite coatings were plasma sprayed on the Ti6A14V substrate with and without an intermediate ZrO2 layer; meanwhile the temperatures of substrates were varied at 90, 140, and 200 °C. The coatings were subjected to the standard adhesion test per ASTM C633-79. The purpose of the investigation was to study the effects of those processing variables on the bonding strength and failure behavior of the system. It is found that the bonding strengths of HA/ZrO2 and HA coatings generally decrease with increasing substrate temperature, except for the HA/ZrO2 coating deposited at 200 °C. The rationale of the results is attributed to the residual stress reported in the literature. Introducing ZrO2 bond coat is found to significantly promote the bonding strength of HA coating. The possible strengthening mechanism is the rougher surface of ZrO2 bond coat and the higher toughness of ZrO2, which provide the mechanical strengthening effects. The slightly denser HA in 200 °C deposited HA coating cannot explain the high bonding strength of the HA/ZrO2 coating, nor the mechanical strengthening effect of ZrO2 intermediate layer should apply. It is believed that a stronger diffusion bonding is formed at the interface of HA and ZrO2, which increases the bonding between them chemically. The bonding strengths of HA/ZrO2 and HA coatings are correlated with the area fraction of adhesive failure of the coatings. The correlation explains the findings in this study.

Studying electron transfer through alkanethiol self-assembled monolayers on a hanging mercury drop electrode using potentiometric measurements.

PubMed

Cohen-Atiya, Meirav; Mandler, Daniel

2006-10-14

A new approach based on measuring the change of the open-circuit potential (OCP) of a hanging mercury drop electrode (HMDE), modified with alkanethiols of different chain length conducted in a solution containing a mixture of Ru(NH3)6(2+) and Ru(NH3)6(3+) is used for studying electron transfer across the monolayer. Following the time dependence of the OCP allowed the extraction of the kinetic parameters, such as the charge transfer resistance (R(ct)) and the electron transfer rate constant (k(et)), for different alkanethiol monolayers. An electron tunneling coefficient, beta, of 0.9 A(-1) was calculated for the monolayers on Hg.

Structure and catalytic activities of ferrous centers confined on the interface between carbon nanotubes and humic acid

NASA Astrophysics Data System (ADS)

Wang, Bing; Zhou, Xiaoyan; Wang, Dongqi; Yin, Jun-Jie; Chen, Hanqing; Gao, Xingfa; Zhang, Jing; Ibrahim, Kurash; Chai, Zhifang; Feng, Weiyue; Zhao, Yuliang

2015-01-01

Preparation of heterogeneous catalysts with active ferrous centers is of great significance for industrial and environmental catalytic processes. Nanostructured carbon materials (NCM), which possess free-flowing π electrons, can coordinate with transition metals, provide a confinement environment for catalysis, and act as potential supports or ligands to construct analogous complexes. However, designing such catalysts using NCM is still seldom studied to date. Herein, we synthesized a sandwich structured ternary complex via the coordination of Fe-loaded humic acid (HA) with C&z.dbd;C bonds in the aromatic rings of carbon nanotubes (CNTs), in which the O/N-Fe-C interface configuration provides the confinement environment for the ferrous sites. The experimental and theoretical results revealed octahedrally/tetrahedrally coordinated geometry at Fe centers, and the strong hybridization between CNT C π* and Fe 3d orbitals induces discretization of the atomic charges on aromatic rings of CNTs, which facilitates O2 adsorption and electron transfer from carbon to O2, which enhances O2 activation. The O2 activation by the novel HA/Fe-CNT complex can be applied in the oxidative degradation of phenol red (PR) and bisphenol A (BPA) in aqueous media.Preparation of heterogeneous catalysts with active ferrous centers is of great significance for industrial and environmental catalytic processes. Nanostructured carbon materials (NCM), which possess free-flowing π electrons, can coordinate with transition metals, provide a confinement environment for catalysis, and act as potential supports or ligands to construct analogous complexes. However, designing such catalysts using NCM is still seldom studied to date. Herein, we synthesized a sandwich structured ternary complex via the coordination of Fe-loaded humic acid (HA) with C&z.dbd;C bonds in the aromatic rings of carbon nanotubes (CNTs), in which the O/N-Fe-C interface configuration provides the confinement environment for the ferrous sites. The experimental and theoretical results revealed octahedrally/tetrahedrally coordinated geometry at Fe centers, and the strong hybridization between CNT C π* and Fe 3d orbitals induces discretization of the atomic charges on aromatic rings of CNTs, which facilitates O2 adsorption and electron transfer from carbon to O2, which enhances O2 activation. The O2 activation by the novel HA/Fe-CNT complex can be applied in the oxidative degradation of phenol red (PR) and bisphenol A (BPA) in aqueous media. Electronic supplementary information (ESI) available: Optimization of the mass ratios of HA to CNTs and the reaction pH conditions for Fe loading; scanning electron microscope (SEM), UV-Vis-near-infrared, Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR) for CNT-HA; EPR experiment and UPLC-ESI-MS analysis; and DFT calculation. See DOI: 10.1039/c4nr06665k

Contamination of phthalate esters, organochlorine pesticides and polybrominated diphenyl ethers in agricultural soils from the Yangtze River Delta of China.

PubMed

Sun, Jianteng; Pan, Lili; Zhan, Yu; Lu, Hainan; Tsang, Daniel C W; Liu, Wenxin; Wang, Xilong; Li, Xiangdong; Zhu, Lizhong

2016-02-15

To reveal the pollution status associated with rapid urbanization and economic growth, extensive areas of agricultural soils (approximately 45,800 km(2)) in the Yangtze River Delta of China were investigated with respect to selected endocrine disruptor compounds (EDCs), including phthalate esters (PAEs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs). The residues of sum of 15 PAEs, sum of 15 OCPs and sum of 13 PBDEs were in the range of 167-9370 ng/g, 1.0-3520 ng/g, and <1.0-382 ng/g, respectively. The OCPs residuals originated from both historical usage and recent input. Agricultural plastic film was considered to be an important source of PAEs. Discharge from furniture industry was potential major source of PBDEs in this region. The selected pollutants showed quite different spatial distributions within the studied region. It is worth noting that much higher concentrations of the EDCs were found on the borders between Shanghai and the two neighboring provinces, where agriculture and industry developed rapidly in recent years. Contaminants from both agricultural and industrial activities made this area a pollution hotspot, which should arouse more stringent regulation to safeguard the environment and food security. Copyright © 2015 Elsevier B.V. All rights reserved.

Seasonal variations and sources of atmospheric polycyclic aromatic hydrocarbons and organochlorine compounds in a high-altitude city: Evidence from four-year observations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gong, Ping; Wang, Xiaoping; Sheng, Jiujiang

Lijiang is a high-altitude city located on the eastern fringe of the Tibetan Plateau, with complex seasonal atmospheric circulations (i.e. westerly wind, Indian Monsoon, and East Asia Monsoon). Very few previous studies have focused on seasonal variations and sources of organic pollutants in Lijiang. In this study, a four-year air campaign from June 2009 to July 2013 was conducted to investigate the temporal trends and the sources of polycyclic aromatic hydrocarbons (PAHs) and organochlorine compounds [including organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs)]. The atmospheric PAH concentrations in winter are 2-3 times of those in summer, probably because of themore » combined result of enhanced local emission and long-range atmospheric transport (LRAT) during winter. Traffic pollution was the primary local source of PAHs, while biomass burning is the dominant LRAT source. Different from PAHs, OCPs and PCBs mainly underwent LRAT to reach Lijiang. The peak concentrations of most of OCPs occurred in pre-monsoon season and winter, which are carried by air masses from Myanmar and India through westerly winds. As compared with other sites of the Tibetan Plateau, without the direct barrier of the Himalaya, Lijiang is easily contaminated by the incursion of polluted air masses.« less

Seasonal variations and sources of atmospheric polycyclic aromatic hydrocarbons and organochlorine compounds in a high-altitude city: Evidence from four-year observations.

PubMed

Gong, Ping; Wang, Xiaoping; Sheng, Jiujiang; Wang, Hailong; Yuan, Xiaohua; He, Yuanqing; Qian, Yun; Yao, Tandong

2018-02-01

Lijiang is a high-altitude city located on the eastern fringe of the Tibetan Plateau, with complex seasonal atmospheric circulations (i.e. westerly wind, Indian Monsoon, and East Asia Monsoon). Very few previous studies have focused on seasonal variations and sources of organic pollutants in Lijiang. In this study, a four-year air campaign from June 2009 to July 2013 was conducted to investigate the temporal trends and the sources of polycyclic aromatic hydrocarbons (PAHs) and organochlorine compounds [including organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs)]. The atmospheric PAH concentrations in winter are 2-3 times of those in summer, probably because of the combined result of enhanced local emission and long-range atmospheric transport (LRAT) during winter. Traffic pollution was the primary local source of PAHs, while biomass burning is the dominant LRAT source. OCPs and PCBs also mainly underwent LRAT to reach Lijiang. The peak concentrations of most of OCPs occurred in pre-monsoon season and winter, which were carried by air masses from Myanmar and India through westerly winds. As compared with other sites of the Tibetan Plateau, without the direct barrier of the Himalaya, Lijiang is easily contaminated by the incursion of polluted air masses. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparison of different mass spectrometric approaches coupled to gas chromatography for the analysis of organochlorine pesticides in serum samples.

PubMed

Fang, Jing; Wu, Qian; Zhao, Yun; Zhao, Hongzhi; Xu, Shunqing; Cai, Zongwei

2017-01-01

Gas chromatography-triple quadrupole mass spectrometry (GC-QqQMS) was applied for the determination of eight organochlorine pesticides (OCPs) in human serum. OCPs were extracted from the serum sample by solid phase extraction (SPE) and analyzed by gas chromatography mass spectrometry (GC-MS) or gas chromatography tandem mass spectrometry (GC-MS/MS). Electron ionization (EI) and negative chemical ionization (NCI) under two data acquisition modes, namely selected ion monitoring (SIM) and multiple reaction monitoring (MRM), were compared. The use of MRM generally provided higher selectivity and sensitivity because less interference from the sample matrix existed. The EI mode is more suitable for less electronegative compounds such as dichlorodiphenyldichloroethanes (DDDs) with detection limits ranging from 0.0060 to 0.060ng/mL. In the NCI mode, MRM analysis provided good and lower detection limits (0.0011-0.0030ng/mL) for pesticides containing more chlorines. The methods were validated by analyzing the pesticides in spiked serum at different levels with recoveries ranged from 83% to 116% and relative standard deviations of less than 10%. The developed method was applied for the determination of the OCPs in real human serum samples. Copyright © 2016 Elsevier B.V. All rights reserved.

[Distribution characteristics and risk assessment of organochlorine pesticides in soil from Jiufeng Mountain Range in Fujian, China].

PubMed

Huang, Huan-Fang; Qi, Shi-Hua; Qu, Cheng-Kai; Li, Hui; Chen, Wen-Wen; Zhang, Li; Hu, Ting; Shi, Liao

2014-07-01

Totally 81 surface soil samples were collected from Jiufeng Mountain Range, and 8 compounds of organochlorine pesticides (OCPs) were determined by a Ni electron capture detector (GC-ECD) to investigate the distribution, composition, source and potential health risks of these compounds in the study region. The detection ratio of HCHs and DDTs' isomers ranged from 77.78% to 100.00%. Concentrations of HCHs and DDTs in surface soils ranged from 0.97 ng x g(-1) to 247.40 ng x g(-1) (mean 10.17 ng x g(-1)) and 0.01 ng x g(-1) to 384.75 ng x g(-1) (mean 18.91 ng x g(-1)), respectively. Compared with other regions, the pollution of OCPs in Jiufeng Mountain Range stayed at a low level. The residue level in different types of lands was in the order as: paddy field > vegetable land > tea land > woodland. Source analysis indicated that Lindane and dicofol might be used recently in this area. The incremental lifetime, cancer risks (ILCRs) of different age groups (children, youths, and adults) were all within the acceptable risk range of 10(-6) to 10(-4) recommended by USEPA for carcinogenic chemicals. The residue level of OCPs in soil may not cause cancer risk for local residents basically.

Status, distribution and ecological risk of organochlorines (OCs) in the surface sediments from the Ravi River, Pakistan.

PubMed

Syed, Jabir Hussain; Malik, Riffat Naseem; Li, Jun; Chaemfa, Chakra; Zhang, Gan; Jones, Kevin C

2014-02-15

Organochlorines (OCs) including organochlorine pesticides (OCPs) and polychlorinated biphenyl (PCBs) were analyzed in surface sediments from the Ravi River, Punjab, Pakistan. Among the OCPs, hexachlorocyclohexane (HCHs), dichlorodiphenyltrichloroethane (DDTs) and chlordane (cis- and trans-) were most abundant and their concentrations were ranged from n.d to 16.0 ng g(-1), 1.5 to 58.5 ng g(-1) and n.d to 29.0 ng g(-1), respectively. Concentrations of Σ31PCBs ranged from 4.6 to 424.3 ng g(-1) with a mean value of 48.9 ng g(-1). In general, the concentrations of all studied organochlorines (OCs) in sediments collected from the sampling sites in the vicinity of industrial areas were higher than those from the agricultural areas. Compositional analyses of PCBs indicated that penta- and tetra-PCBs homologues were dominant which was consistent with the previous studies. Compared with other areas around the world, levels of OCs in sediments from the Ravi River were within the range, but were found to be much higher than previously reported from Pakistan. According to established sediment quality guidelines (SQGs), screening-level risk assessment of OCPs and PCBs suggested that they have a potential for adverse effects on benthic organisms. Copyright © 2013 Elsevier B.V. All rights reserved.

Levels and risk assessment of hydrocarbons and organochlorines in aerosols from a North African coastal city (Bizerte, Tunisia).

PubMed

Barhoumi, Badreddine; Castro-Jiménez, Javier; Guigue, Catherine; Goutx, Madeleine; Sempéré, Richard; Derouiche, Abdelkader; Achour, Amani; Touil, Soufiane; Driss, Mohamed Ridha; Tedetti, Marc

2018-05-09

The aim of this study was to assess, for the first time, the concentrations, sources, dry deposition and human health risks of polycyclic aromatic hydrocarbons (PAHs), aliphatic hydrocarbons (AHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in total suspended particle (TSP) samples collected in Bizerte city, Tunisia (North Africa), during one year (March 2015-January 2016). Concentrations of PAHs, AHs, PCBs and OCPs ranged 0.5-17.8 ng m -3 , 6.7-126.5 ng m -3 , 0.3-11 pg m -3 and 0.2-3.6 pg m -3 , respectively, with higher levels of all contaminants measured in winter. A combined analysis revealed AHs originating from both biogenic and petrogenic sources, while diesel vehicle emissions were identified as dominant sources for PAHs. PCB potential sources included electronic, iron, cement, lubricant factories located within or outside Bizerte city. The dominant OCP congeners were p,p'-DDT and p,p'-DDE, reflecting a current or past use in agriculture. Health risk assessment showed that the lifetime excess cancer risk from exposure to airborne BaP was negligible in Bizerte, except in winter, where a potential risk to the local population may occur. Copyright © 2018 Elsevier Ltd. All rights reserved.

Relationship between organochlorine pesticides and stress indicators in hawksbill sea turtle (Eretmochelys imbricata) nesting at Punta Xen (Campeche), Southern Gulf of Mexico.

PubMed

Tremblay, Nelly; Ortíz Arana, Alejandro; González Jáuregui, Mauricio; Rendón-von Osten, Jaime

2017-03-01

Data on the impact of environmental pollution on the homeostasis of sea turtles remains scarce, particularly in the Southern Gulf of Mexico. As many municipalities along the coastline of the Yucatan Peninsula do not rely on a waste treatment plant, these organisms could be particularly vulnerable. We searched for relationships between the presence of organochlorine pesticides (OCP) and the level of several oxidative and pollutant stress indicators of the hawksbill sea turtle (Eretmochelys imbricata) during the 2010 nesting season at Punta Xen (Campeche, Mexico). Of the 30 sampled sea turtles, endosulfans, aldrin related (aldrin, endrin, dieldrin, endrin ketone, endrin aldehyde) and dichlorodiphenyldichloroethylene (DDT) families were detected in 17, 21 and 26, respectively. Significant correlation existed between the size of sea turtles with the concentration of methoxychlor, cholinesterase activity in plasma and heptachlors family, and catalase activity and hexachlorohexane family. Cholinesterase activity in washed erythrocytes and lipid peroxidation were positively correlated with glutathione reductase activity. Antioxidant enzyme actions seem adequate as no lipids damages were correlated with any OCPs. Future studies are necessary to evaluate the effect of OCPs on males of the area due to the significant detection of methoxychlor, which target endocrine functioning and increases its concentration with sea turtles size.

Levels of Organochlorine Pesticides and Heavy Metals in Surface Waters of Konya Closed Basin, Turkey

PubMed Central

Aydin, Mehmet Emin; Ozcan, Senar; Beduk, Fatma; Tor, Ali

2013-01-01

The concentrations of organochlorine pesticides (OCPs), including α-, β-, γ-, and δ-hexachlorocyclohexane (HCH), heptachlor, heptachlor epoxide, dieldrin, aldrin, endrin, endrin aldehyde, endrin ketone, endosulfan I, endosulfan II, endosulfan sulfate, p,p′-DDE, p,p′-DDD, p,p′-DDT, methoxychlor, chlordane I, chlordane II, and heavy metals, such as As, Cr, Cu, Fe, Mn, and Ni in surface water samples from the Konya closed basin were determined to evaluate the level of contamination. Among all HCH isomers, β-HCH is the main isomer with a concentration range of 0.015–0.065 μg/L. DDE, DDD, and DDT were almost determined in all samples, in which DDE isomer had the highest concentration ranged from not detected to 0.037 μg/L. In all studied OCPs, aldrin showed the highest concentration at 0.220 μg/L. The concentrations of heavy metals in water samples were observed with order: Mn < Cu < Ni < As < Cr < Fe. In some samples, As, Fe, and Cr concentrations exceeded the drinking water quality recommended by EU, US EPA, WHO, and Turkish Regulation, while Cu, Ni, and Mn concentrations are below the guideline values. The levels of both OCPs and heavy metals were also compared with other previously published data. PMID:23533363

Evaluation of Genotoxic and Mutagenic Activity of Organic Extracts from Drinking Water Sources

PubMed Central

Guan, Ying; Wang, Xiaodong; Wong, Minghung; Sun, Guoping; An, Taicheng; Guo, Jun

2017-01-01

An increasing number of industrial, agricultural and commercial chemicals in the aquatic environment lead to various deleterious effects on organisms, which is becoming a serious global health concern. In this study, the Ames test and SOS/umu test were conducted to investigate the potential genotoxicity and mutagenicity caused by organic extracts from drinking water sources. Organic content of source water was extracted with XAD-2 resin column and organic solvents. Four doses of the extract equivalent to 0.25, 0.5, 1 and 2L of source water were tested for toxicity. All the water samples were collected from six different locations in Guangdong province. The results of the Ames test and SOS/umu test showed that all the organic extracts from the water samples could induce different levels of DNA damage and mutagenic potentials at the dose of 2 L in the absence of S9 mix, which demonstrated the existence of genotoxicity and mutagenicity. Additionally, we found that Salmonella typhimurium strain TA98 was more sensitive for the mutagen. Correlation analysis between genotoxicity, Organochlorine Pesticides (OCPs) and Polycyclic Aromatic Hydrocarbons (PAHs) showed that most individual OCPs were frame shift toxicants in drinking water sources, and there was no correlation with total OCPs and PAHs. PMID:28125725

Hormonal contraception does not increase women's HIV acquisition risk in Zambian discordant couples, 1994-2012.

PubMed

Wall, Kristin M; Kilembe, William; Vwalika, Bellington; Htee Khu, Naw; Brill, Ilene; Chomba, Elwyn; Johnson, Brent A; Haddad, Lisa; Tichacek, Amanda; Allen, Susan

2015-06-01

To determine the impact of hormonal contraceptive methods on risk of HIV acquisition among HIV-negative women cohabiting with HIV-positive male partners. From 1994-2012, HIV discordant couples recruited from a couples' voluntary HIV counseling and testing center in Lusaka, Zambia were followed longitudinally. HIV-negative partners were tested quarterly. This analysis is restricted to couples in which the man was HIV-positive and the woman was HIV-negative at enrollment and the man was not on antiretroviral treatment. Multivariate Cox models evaluated associations between time-varying contraceptive methods and HIV acquisition among women. Sensitivity analyses explored exposure misclassification and time-varying confounder mediation. Among 1393 couples, 252 incident infections occurred in women over 2842 couple-years (8.9 infections per 100 couple-years; 95% CI, 7.8-10.0). Multivariate Cox models indicated that neither injectable [adjusted hazard ratio (aHR)=1.2; 95% CI, 0.8-1.7], oral contraceptive pill (OCP, aHR=1.3; 95% CI, 0.9-1.8), or implant (aHR=1.1; 95% CI, 0.5-2.2) use was significantly associated with HIV acquisition relative to non-hormonal contraception controlling for woman's age, literacy and time-varying measures of genital ulceration/inflammation. This remained true when only looking at the subset of infections acquired from the spouse (82% of infections) and additionally controlling for baseline HIV viral load of the male partner, pregnancy status, and time-varying measures of sperm on a vaginal swab wet prep and self-reported unprotected sex. OCP and injectable users reported more unprotected sex (p<.001), and OCP users were more likely to have sperm on vaginal swab (p=.1) than nonhormonal method users. We found no association between hormonal contraception and HIV acquisition risk in women. Condom use and reinforced condom counseling should always be recommended for HIV discordant couples. HIV testing of sex partners together is critical to establish HIV risk, ascertain couple fertility intentions and counsel appropriately. These findings add to a controversial literature and uniquely address several common design and analytic challenges faced by previous studies. After controlling for confounders, we found no association between hormonal contraception and HIV acquisition risk in women. We support promoting condoms for HIV prevention and increasing the contraceptive method mix to decrease unintended pregnancy. Copyright © 2015 Elsevier Inc. All rights reserved.

Polychlorinated biphenyls and organochlorine pesticides in River Brahmaputra from the outer Himalayan Range and River Hooghly emptying into the Bay of Bengal: Occurrence, sources and ecotoxicological risk assessment.

PubMed

Chakraborty, Paromita; Khuman, Sanjenbam Nirmala; Selvaraj, Sakthivel; Sampath, Srimurali; Devi, Ningombam Linthoingambi; Bang, John J; Katsoyiannis, Athanasios

2016-12-01

River Brahmaputra (RB) from the outer Himalayan Range and River Hooghly (RH), a distributary of River Ganga, are the two largest transboundary perennial rivers supplying freshwater to the northeastern and eastern states of India. Given the history of extensive usage of organochlorine pesticides and increasing industrialization along the banks of these rivers we investigated selected organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in the surface water of River Brahmaputra and River Hooghly. Geomean of ΣOCPs (53 ng L -1 ) and Σ 19 PCBs (108 ng L -1 ) was higher in RH compared with geomean of ΣOCPs (24 ng L -1 ) and Σ 19 PCBs (77 ng L -1 ) in RB. Among OCPs, γ-HCH showed maximum detection frequency in both the rivers reflecting ongoing lindane usage. DDT and endosulfan residues were observed at specific locations where past or ongoing sources exist. Elevated concentrations of heavier congeners (penta-hepta) were observed in those sites along RH where port and industrial activities were prevalent including informal electronic waste scrap processing units. Furthermore along River Hooghly PCB-126 was high in the suburban industrial belt of Howrah district. PCBs were found to be ubiquitously distributed in RB. Atmospheric transport of tri- and tetra-PCB congeners from the primary source regions might be a major contributor for PCBs in RB. Heavier congeners (penta-nona) in the urban centers of RB were likely due to industrial wastewater runoff from the oil refineries in the Brahmaputra valley. Σ 19 PCBs concentrations in this study exceeded the USEPA recommended limit for freshwater. Ecotoxicological risk assessment showed the possibility of adverse impact on the organisms in the lower trophic level due to DDT and lindane contamination. Impact of endosulfan on fishes might be of considerable concern for aquatic environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

A circumpolar perspective of atmospheric organochlorine pesticides (OCPs): Results from six Arctic monitoring stations in 2000-2003

NASA Astrophysics Data System (ADS)

Su, Yushan; Hung, Hayley; Blanchard, Pierrette; Patton, Gregory W.; Kallenborn, Roland; Konoplev, Alexei; Fellin, Phil; Li, Henrik; Geen, Charles; Stern, Gary; Rosenberg, Bruno; Barrie, Leonard A.

Air concentrations of organochlorine pesticides (OCPs) were measured on a weekly basis in 2000-2003 at six Arctic stations, which include Alert, Kinngait, and Little Fox Lake in Canada; Point Barrow in the USA; Valkarkai in Russia; and Zeppelin in Norway. These stations cover a large region in the Arctic, providing a comprehensive perspective on OCPs in the circumpolar atmosphere. Currently used pesticide endosulfan I had similar concentrations across the stations in November-May, whereas large spatial divergence was found in June-October. This implies the extensive usage of endosulfan during summertime followed by long-range transport to the Arctic. The median air concentration of endosulfan I was 3.2 pg m -3 ( n=245). Seasonally and spatially uniform concentrations of legacy chlordane-related compounds indicated that the influence of primary emissions on Arctic air has become less important than volatilization emissions. Median air concentrations (pg m -3) of trans-chlordane, cis-chlordane, trans-nonachlor, oxychlordane, and heptachlor exo-epoxide were 0.20 ( n=413), 0.58 ( n=413), 0.44 ( n=413), 0.30 ( n=245), and 0.54 ( n=244), respectively. Although extensive usage was banned in the 1970s, large spatial variations reflected that DDT-related compounds were not well mixed in Arctic air. Concentrations of DDT-related compounds were low in general, and median concentrations of p, p'-DDT, o, p'-DDT, p, p'-DDE, o, p'-DDE, and ∑ 4DDT were 0.10, 0.18, 0.37, 0.10, and 0.79 pg m -3 ( n=418), respectively. Air concentrations of pentachloroanisole and dieldrin showed strong seasonal/spatial variations with median values of 3.8 and 0.48 pg m -3 ( n=245). Uniform concentrations were observed for octachlorostyrene with a median of 0.32 pg m -3 ( n=245). Arctic air concentrations of other measured OCPs, such as endrin, heptachlor, methoxychlor, mirex, photomirex, tetrachloroveratrole, trichloroveratrol, and trifluralin, were generally low and mostly below method detection limits.

A 50-years record of dichloro-diphenyl-trichloroethanes and hexachlorocyclohexanes in lake sediments and penguin droppings on King George Island, Maritime Antarctic.

PubMed

Sun, Li-guang; Yin, Xue-bin; Pan, Can-ping; Wang, Yu-hong

2005-01-01

Since the ban on the use of organochlorine pesticides (OCPs) such as dichloro-diphenyl-trichloroethane (DDT) and hexachlorocyclohexane(HCH) in agriculture, their levels have generally dropped. In a number of cases, however, the levels of these OCPs were found to be unchanging or even increasing after the ban. With the aim to unveil the possible causes of these exceptions, we collected two lake cores from King George Island, West Antarctica, and determined their accumulation flux profiles and temporal trends of these OCPs. In the lake core sediments with glacier meltwater input, the accumulation flux of DDT shows an abnormal peak around 1980s in addition to the expected one in 1960s. In the lake core sediments without glacier meltwater input, the accumulation flux of DDT shows a gradual decline trend after the peak in 1960s. This striking difference in the DDT flux profiles between the two lake cores is most likely caused by the regional climate warming and the resulted discharge of the DDT stored in the Antarctic ice cap into the lakes in the Antarctic glacier frontier. Furthermore, to investigate the change of OCPs loadings in the Antarctic coastal ecosystem, we reconstructed the HCH and DDT concentration profiles in penguin droppings and observed a gradual increase for the former and a continuous decrease for the latter during the past 50 years. The increase of HCH seems to be due to the regional warming from the early 1970s and the resulted HCH discharge to the coastal ecosystem by glaciers' meltwater and the illegal use of HCH in the Southern Hemisphere in the recent decade. Thedifferent temporal trends of HCH and DDT accumulation rate in the lake core with glacier meltwater input and the aged penguin droppings can be explained by their different water-soluble property.

Accumulation of toxic metals and organic micro-pollutants in sediments from tropical urban rivers, Kinshasa, Democratic Republic of the Congo.

PubMed

Kilunga, Pitchouna I; Sivalingam, Periyasamy; Laffite, Amandine; Grandjean, Dominique; Mulaji, Crispin K; de Alencastro, Luiz Felippe; Mpiana, Pius T; Poté, John

2017-07-01

The increasing contamination of fresh water resource by toxic metals and Persistence Organic Pollutants (POPs) is a major environmental concern globally. In the present investigation, surface sediments collected from three main rivers named, Makelele, Kalamu and Nsanga, draining through the city of Kinshasa, Democratic Republic of the Congo, were characterized for grain size, organic matter, toxic metals, POPs (including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs)), and polycyclic aromatic hydrocarbons (PAHs). Furthermore, enrichment factor (EF) and geoaccumulation index (Igeo) were performed to determine metal source and pollution status. The results highlighted high concentration of toxic metals in all sediment samples, reaching the values (mg kg -1 ) of 325 (Cu), 549 (Zn), 165 (Pb) and 1.5 (Cd). High values of PCBs and OCPs were detected in sediment samples, e.g. in Makelele river, PCB values ranged from 0.9 to 10.9 with total PCBs (∑7 PCBs × 4.3): 169.3 μg kg -1 ; OCPs from 21.6 to 146.8 with ∑OCPs: 270.6 μg kg -1 . The PBDEs concentrations were higher in investigated rivers comparatively with values detected in many rivers from Sub-Saharan Africa. The ΣPAHs value ranged from 22.6 to 1011.9 μg kg -1 . River contamination may be explained by local intense domestic activities, urban and agricultural runoff, industrial and hospital wastewaters discharge into the rivers without prior treatment. This research provides not only a first baseline information on the extent of contamination in this tropical ecosystem but also represents useful tools incorporated to evaluate sediment quality in the river receiving systems which can be applied to similar aquatic environments. Copyright © 2017 Elsevier Ltd. All rights reserved.

Spatial and seasonal variations of pesticide contamination in agricultural soils and crops sample from an intensive horticulture area of Hohhot, North-West China.

PubMed

Zhang, Fujin; He, Jiang; Yao, Yiping; Hou, Dekun; Jiang, Cai; Zhang, Xinxin; Di, Caixia; Otgonbayar, Khureldavaa

2013-08-01

The spatial variability and temporal trend in concentrations of the organochlorine pesticides (OCPs), hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT), in soils and agricultural corps were investigated on an intensive horticulture area in Hohhot, North-West China, from 2008 to 2011. The most frequently found and abundant pesticides were the metabolites of DDT (p,p'-DDE, p,p'-DDT, o,p'-DDT and p,p'-DDD). Total DDT concentrations ranged from ND (not detectable) to 507.41 ng/g and were higher than the concentration of total HCHs measured for the range of 4.84-281.44 ng/g. There were significantly positive correlations between the ∑DDT and ∑HCH concentrations (r (2)>0.74) in soils, but no significant correlation was found between the concentrations of OCPs in soils and clay content while a relatively strong correlation was found between total OCP concentrations and total organic carbon (TOC). β-HCH was the main isomer of HCHs, and was detected in all samples; the maximum proportion of β-HCH compared to ∑HCHs (mean value 54%) was found, suggesting its persistence. The α/γ-HCH ratio was between 0.89 and 5.39, which signified the combined influence of technical HCHs and lindane. Low p,p'-DDE/p,p'-DDT in N1, N3 and N9 were found, reflecting the fresh input of DDTs, while the relatively high o,p'-DDT/p,p'-DDT ratios indicated the agricultural application of dicofol. Ratios of DDT/(DDE+DDD) in soils do not indicate recent inputs of DDT into Hohhot farmland soil environment. Seasonal variations of OCPs featured higher concentrations in autumn and lower concentrations in spring. This was likely associated with their temperature-driven re-volatilization and application of dicofol in late spring.

One-step green synthesis of β-cyclodextrin/iron oxide-reduced graphene oxide nanocomposite with high supramolecular recognition capability: Application for vortex-assisted magnetic solid phase extraction of organochlorine pesticides residue from honey samples.

PubMed

Mahpishanian, Shokouh; Sereshti, Hassan

2017-02-17

In this research, β-cyclodextrin/iron oxide reduced graphene oxide hybrid nanostructure (β-CD/MRGO) with high water dispersability, excellent magnetic responsivity and molecular selectivity was prepared via a facile one step green strategy. The obtained nanomaterial was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, and vibrating sample magnetometry (VSM), which confirmed the modification of GO with β-CD and magnetic nanoparticles. The formation mechanism of β-CD/MRGO was also discussed. The prepared magnetic nanocomposite was then applied as adsorbent in the vortex-assisted magnetic solid phase extraction (MSPE) of 16 organochlorine pesticides (OCPs) from honey samples prior to gas chromatography-electron capture detection (GC-ECD) analysis. Optimum extraction conditions have been assessed with respect to vortex time, sample pH, adsorbent amount, and salt concentration as well as desorption conditions (type and volume of desorption solvent and desorption time). A good level of linearity (2-10,000ngkg -1 ) with satisfactory determination coefficients (R 2 >0.9966) and suitable precision (%RSDs less than 7.8) was obtained for OCPs under the optimal conditions. The limits of detection and quantification of the method were obtained in the sub-parts per trillion (ppt) to parts per trillion range (LOD: 0.52-3.21ngkg -1 ; LOQ: 1.73-10.72ngkg -1 ) based on 3 and 10 signal to noise ratios, respectively. The MSPE method was successfully applied to analysis of OCPs in honey samples with recoveries in the range of 78.8% to 116.2% and RSDs (n=3) below 8.1%. The results demonstrated that β-CD/MRGO could exhibit good supramolecular recognition, enrichment capability and high extraction recoveries toward OCPs. Copyright © 2017 Elsevier B.V. All rights reserved.

An Experimental Study of Electronic States at Metal-Dielectric Interfaces.

DTIC Science & Technology

1981-03-13

COOH) ha been measured usang the frus. FURTAK, G.R. TROTT , and B.H. L00, Ames Lab.-USDOE* and tamted total interns) reflection technique. Enhancments...Klutznick, Secretary Luther H. Hodges, Jr., Deputy Secretary Jordan J. Baruch, Assistant Secretary for Productivity, Technology, and Innovation

The wildland-urban interface raster dataset of Catalonia.

PubMed

Alcasena, Fermín J; Evers, Cody R; Vega-Garcia, Cristina

2018-04-01

We provide the wildland urban interface (WUI) map of the autonomous community of Catalonia (Northeastern Spain). The map encompasses an area of some 3.21 million ha and is presented as a 150-m resolution raster dataset. Individual housing location, structure density and vegetation cover data were used to spatially assess in detail the interface, intermix and dispersed rural WUI communities with a geographical information system. Most WUI areas concentrate in the coastal belt where suburban sprawl has occurred nearby or within unmanaged forests. This geospatial information data provides an approximation of residential housing potential for loss given a wildfire, and represents a valuable contribution to assist landscape and urban planning in the region.

Homology modeling study toward identifying structural properties in the HA2 B-loop that would influence the HA1 receptor-binding site.

PubMed

Cueno, Marni E; Imai, Kenichi; Shimizu, Kazufumi; Ochiai, Kuniyasu

2013-07-01

Influenza hemagglutinin (HA) consists of a fibrous globular stem (HA2) inserted into the viral membrane supporting a globular head (HA1). HA1 receptor-binding has been hypothesized to be structurally correlated to the HA2 B-loop, however, this was never fully understood. Here, we elucidated the structural relationship between the HA2 B-loop and the HA1 receptor-binding site (RBS). Throughout this study, we analyzed 2486 H1N1 HA homology models obtained from human, swine and avian strains during 1976-2012. Quality of all homology models were verified before further analyses. We established that amino acid residue 882 is putatively strain-conserved and differs in the human (K882), swine (H882) and avian (N882) strains. Moreover, we observed that the amino acid at residue 882 and, similarly, its orientation has the potential to influence the HA1 RBS diameter measurements which we hypothesize may consequentially affect influenza H1N1 viral infectivity, immune escape, transmissibility, and evolution. Copyright © 2013 Elsevier Inc. All rights reserved.

Uniformly-dispersed nanohydroxapatite-reinforced poly(ε-caprolactone) composite films for tendon tissue engineering application.

PubMed

Tong, Shi Yun; Wang, Zuyong; Lim, Poon Nian; Wang, Wilson; Thian, Eng San

2017-01-01

Regeneration of injuries at tendon-to-bone interface (TBI) remains a challenging issue due to the complex tissue composition involving both soft tendon tissues and relatively hard bone tissues. Tissue engineering using polymeric/ceramic composites has been of great interest to generate scaffolds for tissue's healing at TBI. Herein, we presented a novel method to blend polymers and bioceramics for tendon tissue engineering application. A homogeneous composite comprising of nanohydroxyapatite (nHA) particles in poly(ε-caprolactone) (PCL) matrix was obtained using a combination of solvent and mechanical blending process. X-ray diffraction analysis showed that the as-fabricated PCL/nHA composite film retained phase-pure apatite and semi-crystalline properties of PCL. Infrared spectroscopy spectra confirmed that the PCL/nHA composite film exhibited the characteristics functional groups of PCL and nHA, without alteration to the chemical properties of the composite. The incorporation of nHA resulted in PCL/nHA composite film with improved mechanical properties such as Young's Modulus and ultimate tensile stress, which were comparable to that of the native human rotator tendon. Seeding with human tenocytes, cells attached on the PCL/nHA composite film, and after 14days of culturing, these cells could acquire elongated morphology without induced cytotoxicity. PCL/nHA composite film could also result in increased cell metabolism with prolonged culturing, which was comparable to that of the PCL group and higher than that of the nHA group. All these results demonstrated that the developed technique of combining solvent and mechanical blending could be applied to fabricate composite films with potential for tendon tissue engineering applications. Copyright © 2016 Elsevier B.V. All rights reserved.

Fabrication of mineralized electrospun PLGA and PLGA/gelatin nanofibers and their potential in bone tissue engineering.

PubMed

Meng, Z X; Li, H F; Sun, Z Z; Zheng, W; Zheng, Y F

2013-03-01

Surface mineralization is an effective method to produce calcium phosphate apatite coating on the surface of bone tissue scaffold which could create an osteophilic environment similar to the natural extracellular matrix for bone cells. In this study, we prepared mineralized poly(D,L-lactide-co-glycolide) (PLGA) and PLGA/gelatin electrospun nanofibers via depositing calcium phosphate apatite coating on the surface of these nanofibers to fabricate bone tissue engineering scaffolds by concentrated simulated body fluid method, supersaturated calcification solution method and alternate soaking method. The apatite products were characterized by the scanning electron microscopy (SEM), Fourier transform-infrared spectroscopy (FT-IR), and X-ray diffractometry (XRD) methods. A large amount of calcium phosphate apatite composed of dicalcium phosphate dihydrate (DCPD), hydroxyapatite (HA) and octacalcium phosphate (OCP) was deposited on the surface of resulting nanofibers in short times via three mineralizing methods. A larger amount of calcium phosphate was deposited on the surface of PLGA/gelatin nanofibers rather than PLGA nanofibers because gelatin acted as nucleation center for the formation of calcium phosphate. The cell culture experiments revealed that the difference of morphology and components of calcium phosphate apatite did not show much influence on the cell adhesion, proliferation and activity. Copyright © 2012 Elsevier B.V. All rights reserved.

Concentration polarization of hyaluronan on the surface of the synovial lining of infused joints

PubMed Central

Lu, Y; Levick, JR; Wang, W

2004-01-01

Hyaluronan (HA) in joints conserves the lubricating synovial fluid by making trans-synovial fluid escape almost insensitive to pressure elevation (e.g. effusions, joint flexion). This phenomenon, ‘outflow buffering’, was discovered during HA infusion into the rabbit knee joint cavity. It was also found that HA is partially reflected by the joint lining (molecular sieving), and that the reflected fraction R decreases as trans-synovial filtration rate Q is increased. It was postulated therefore that outflow buffering is mediated by HA reflection. Reflection creates a HA concentration polarization layer, the osmotic pressure of which opposes fluid loss. A steady-state, cross-flow ultrafiltration model was previously used to explain the outflow buffering and negative R-vs.-Q relation. However, the steady-state, cross-perfusion assumptions restricted the model's applicability for an infused, dead-end cavity or a non-infused joint during cyclical motion. We therefore developed a new, non-steady-state model which describes the time course of dead-end, partial HA ultrafiltration. The model describes the progressive build-up of a HA concentration polarization layer at the synovial surface over time. Using experimental parameter values, the model successfully accounts for the observed negative R-vs.-Q relation and shows that the HA reflected fraction (R) also depends on HA diffusivity, membrane area expansion and the synovial HA reflection coefficient. The non-steady-state model thus explains existing experimental work, and it is a key stage in understanding synovial fluid turnover in intact, moving, human joints or osteoarthritic joints treated by HA injections. PMID:15579541

The developmental association of relationship quality, hormonal contraceptive choice and condom non-use among adolescent women.

PubMed

Sayegh, M Aaron; Fortenberry, J Dennis; Shew, Marcia; Orr, Donald P

2006-09-01

Consistent condom use is critical to efforts to prevent sexually transmitted infections among adolescents, but condom use may decline as relationships and contraceptive needs change. The purpose of this research is to assess changes in condom non-use longitudinally in the context of changes in relationship quality, coital frequency and hormonal contraceptive choice. Participants were women (aged 14-17 years at enrollment) recruited from three urban adolescent medicine clinics. Data were collected at three-month intervals using a face-to-face structured interview. Participants were able to contribute up to 10 interviews, but on average contributed 4.2 interviews over the 27-month period. Independent variables assessed partner-specific relationship quality (five items; scale range 5-25; alpha = .92, e.g., this partner is a very important person to me); and, number of coital events with a specific partner. Additional items assessed experience with oral contraceptive pills (OCP) use and injected depo medroxy-progesterone acetate (DMPA). The outcome variable was number of coital events without condom use during the past three months. Analyses were conducted as a three-level hierarchical linear growth curve model using HLM 6. The Level 1 predictor was time, to test the hypothesis that condom non-use increases over time. Level 2 predictors assessed relationship quality and coital frequency across all partners to assess hypotheses that participants' condom non-use increases over time as a function of relationship quality and coital frequency. Level 3 predictors assessed the participant-level influence of OCP or DMPA experience on time-related changes in condom non-use. A total of 176 women reported 279 sex partners and contributed 478 visits. Both average coital frequency and average condom non-use linearly increased during the 27-month follow-up. At any given follow-up, about 35% reported recent OCP use, and 65% reported DMPA use. HLM analyses showed that condom non-use increased as a function of time (beta = .12; p = .03, Level 1 analysis). Increased condom non-use over time was primarily a function of increased coital frequency (beta = .01; p = .00), although higher levels of relationship quality were associated with increased condom non-use at enrollment (beta = .44; p = .00, Level 2 analysis). The temporal rise in condom non-use significantly increased among DMPA users (beta = .06; p = .00) but not OCP users (Level 3 analysis) (beta = -.04; p = .06). Developmentally, relationship characteristics and coital frequency appear to have increasing weight in decisions about condom use. Hormonal contraceptive methods are not equivalently associated with the overall temporal decline in condom use. Future research associated with dual contraceptive/condom use should address differential factors associated condom use in combination with different hormonal methods.

Anti-infective efficacy, cytocompatibility and biocompatibility of a 3D-printed osteoconductive composite scaffold functionalized with quaternized chitosan.

PubMed

Yang, Ying; Yang, Shengbing; Wang, Yugang; Yu, Zhifeng; Ao, Haiyong; Zhang, Hongbo; Qin, Ling; Guillaume, Olivier; Eglin, David; Richards, R Geoff; Tang, Tingting

2016-12-01

Contaminated or infected bone defects remain serious challenges in clinical trauma and orthopaedics, and a bone substitute with both osteoconductivity and antibacterial properties represents an improvement for treatment strategy. In this study, quaternized chitosan (hydroxypropyltrimethyl ammonium chloride chitosan, HACC) was grafted to 3D-printed scaffolds composed of polylactide-co-glycolide (PLGA) and hydroxyapatite (HA), in order to design bone engineering scaffolds endowed with antibacterial and osteoconductive properties. We found that both the PLGA/HA/HACC and PLGA/HACC composite scaffolds decreased bacterial adhesion and biofilm formation under in vitro and in vivo conditions. Additionally, ATP leakage assay indicated that immobilizing HACC on the scaffolds could effectively disrupt microbial membranes. Using human bone marrow-derived mesenchymal stem cells (hBMSCs), we demonstrated that HA incorporated scaffolds, including PLGA/HA and PLGA/HA/HACC, favoured cell attachment, proliferation, spreading and osteogenic differentiation compared to HA-free PLGA or PLGA/HACC scaffolds. Finally, an in vivo biocompatibility assay conducted on rats, showed that HA incorporated scaffolds (including PLGA/HA and PLGA/HA/HACC scaffolds) exhibited good neovascularization and tissue integration. Taken together, our findings support the approach for developing porous PLGA/HA/HACC composite scaffold with potential clinical application in the treatment of infected bone. Although plenty of conductive scaffold biomaterials have been exploited to improve bone regeneration under infection, potential tissue toxicity under high concentration and antibiotic-resistance are their main deficiencies. This study indicated that HACC-grafted PLGA/HA composite scaffold prepared using an innovative 3D-printing technique and covalent grafting strategy showed significantly enhanced antibacterial activities, especially against the antibiotic-resistant strains, together with good osteogenic activity and biocompatibility. Therefore, it provides an effective porous composite scaffold to combat the infected bone defect in clinic with decreased risks of bacterial resistance and open a feasible strategy for the modification of scaffold interfaces involved in the bone regeneration and anti-infection. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Selenium cycling across soil-plant atmosphere interfaces: a critical review

USDA-ARS?s Scientific Manuscript database

Selenium (Se) is an essential element for humans and animals, which occurs ubiquitously in the environment. It is present in trace amounts in both organic and inorganic forms in marine and freshwater systems, soils, biomass, and in the atmosphere. Low Se levels in certain terrestrial environments ha...

Molecular dynamics simulations of dense plasmas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Collins, L.A.; Kress, J.D.; Kwon, I.

1993-12-31

We have performed quantum molecular dynamics simulations of hot, dense plasmas of hydrogen over a range of temperatures(0.1-5eV) and densities(0.0625-5g/cc). We determine the forces quantum mechanically from density functional, extended Huckel, and tight binding techniques and move the nuclei according to the classical equations of motion. We determine pair-correlation functions, diffusion coefficients, and electrical conductivities. We find that many-body effects predominate in this regime. We begin to obtain agreement with the OCP and Thomas-Fermi models only at the higher temperatures and densities.

Identification of trace organic pollutants in drinking water and the associated human health risks in Jiangsu Province, China.

PubMed

Li, Bing; Qu, Changsheng; Bi, Jun

2012-06-01

Organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs), dibutyl phthalate (DNBP) and di-2-ethylhexyl phthalate (DEHP) were all detectable in surface water in Jiangsu Province, China. Concentrations of OCPs ranged from 5.13 to 8.15 ng/L. PAHs were found ranging from 14.7 to 24.5 ng/L. Concentrations of DNBP and DEHP ranged from 16 to 5,857.5 ng/L and 556 to 15,670.7 ng/L, respectively. Greater than 70 % of chemicals were removed in water treatment processes. The carcinogenic risks posed by trace organic pollutants through tap water ingestion were lower than 10(-6), and the noncarcinogenic risks were less than 10(-5).

Modelling soil erosion in a Mediterranean watershed: Comparison between SWAT and AnnAGNPS models.

PubMed

Abdelwahab, O M M; Ricci, G F; De Girolamo, A M; Gentile, F

2018-06-20

In this study, the simulations generated by two of the most widely used hydrological basin-scale models, the Annualized Agricultural Non-Point Source (AnnAGNPS) and the Soil and Water Assessment Tool (SWAT), were compared in a Mediterranean watershed, the Carapelle (Apulia, Southern Italy). Input data requirements, time and efforts needed for input preparation, strength and weakness points of each model, ease of use and limitations were evaluated in order to give information to users. Models were calibrated and validated at monthly time scale for hydrology and sediment load using a four year period of observations (streamflow and suspended sediment concentrations). In the driest year, the specific sediment load measured at the outlet was 0.89 t ha -1 yr -1 , while the simulated values were 0.83 t ha -1 yr -1 and 1.99 t ha -1 yr -1 for SWAT and AnnAGNPS, respectively. In the wettest year, the specific measured sediment load was 7.45 t ha -1 yr -1 , and the simulated values were 8.27 t ha -1 yr -1 and 6.23 t ha -1 yr -1 for SWAT and AnnAGNPS, respectively. Both models showed from fair to a very good correlation between observed and simulated streamflow and satisfactory for sediment load. Results showed that most of the basin is under moderate (1.4-10 t ha -1 yr -1 ) and high-risk erosion (> 10 t ha -1 yr -1 ). The sediment yield predicted by the SWAT and AnnAGNPS models were compared with estimates of soil erosion simulated by models for Europe (PESERA and RUSLE2015). The average gross erosion estimated by the RUSLE2015 model (12.5 t ha -1 yr -1 ) resulted comparable with the average specific sediment yield estimated by SWAT (8.8 t ha -1 yr -1 ) and AnnAGNPS (5.6 t ha -1 yr -1 ), while it was found that the average soil erosion estimated by PESERA is lower than the other estimates (1.2 t ha -1 yr -1 ). Copyright © 2018 Elsevier Inc. All rights reserved.

Hierarchical Microspheres Constructed from Chitin Nanofibers Penetrated Hydroxyapatite Crystals for Bone Regeneration.

PubMed

Duan, Bo; Shou, Kangquan; Su, Xiaojuan; Niu, Yahui; Zheng, Guan; Huang, Yao; Yu, Aixi; Zhang, Yu; Xia, Hong; Zhang, Lina

2017-07-10

Chitin exists abundantly in crab and shrimp shells as the template of the minerals, which inspired us to mineralize it for fabricating bone grafting materials. In the present work, chitin nanofibrous microspheres were used as the matrix for in situ synthesis of hydroxyapatite (HA) crystals including microflakes, submicron-needles, and submicron-spheres, which were penetrated by long chitin nanofibers, leading to the hierarchical structure. The shape and size of the HA crystals could be controlled by changing the HA synthesis process. The tight interface adhesion between chitin and HA through the noncovanlent bonds occurred in the composite microspheres, and HAs were homogeneously dispersed and bounded to the chitin nanofibers. In our findings, the inherent biocompatibilities of the both chitin and HA contributed the bone cell adhesion and osteoconduction. Moreover, the chitin microsphere with submicron-needle and submicron-sphere HA crystals remarkably promoted in vitro cell adhesion and in vivo bone healing. It was demonstrated that rabbits with 1.5 cm radius defect were almost cured completely within three months in a growth factor- and cell-free state, as a result of the unique surface microstructure and biocompatibilities of the composite microspheres. The microsphere scaffold displayed excellent biofunctions and an appropriate biodegradability. This work opened up a new avenue to construct natural polymer-based organic-inorganic hybrid microspheres for bone regeneration.

A Human Clinical, Histological, Histomorphometrical, and Radiographical Study on Biphasic HA-Beta-TCP 30/70 in Maxillary Sinus Augmentation.

PubMed

Mangano, Carlo; Sinjari, Bruna; Shibli, Jamil A; Mangano, Francesco; Hamisch, Sabine; Piattelli, Adriano; Perrotti, Vittoria; Iezzi, Giovanna

2015-06-01

By mixing hydroxyapatite (HA) and tricalcium phosphate (TCP), biphasic calcium phosphate ceramics can be obtained, and by varying their ratio it is possible to tailor the characteristics of the biomaterial. The aim of the present human study was to evaluate the histological and radiographical aspects of bone formation in maxillary sinus augmentation using a 30/70 HA-beta-TCP with a reticular structure. A total of 12 patients, undergoing two-stage sinus augmentation procedure using HA-beta-TCP at a ratio of 30/70, were included in the present study. After a 6-month healing period, during implant insertion, radiographical analysis was performed, and then the bone core biopsies were harvested and processed for histology. At radiographic evaluation, the bone gain was on average 6.85 ± 0.60 mm. HA-beta-TCP 30/70 appeared to be lined by newly formed bone, with no gaps at the interface. The histomorphometric analysis revealed 26 ± 2% of residual grafted biomaterial, 29 ± 3% of newly formed bone, and 45 ± 2% of marrow spaces. The present results indicate histologically the high biocompatibility and osteoconductivity of HA-beta-TCP 30/70, and clinically its successful use for sinus augmentation procedures. © 2013 Wiley Periodicals, Inc.

Pervaporation dehydration of ethanol by hyaluronic acid/sodium alginate two-active-layer composite membranes.

PubMed

Gao, Chengyun; Zhang, Minhua; Ding, Jianwu; Pan, Fusheng; Jiang, Zhongyi; Li, Yifan; Zhao, Jing

2014-01-01

The composite membranes with two-active-layer (a capping layer and an inner layer) were prepared by sequential spin-coatings of hyaluronic acid (HA) and sodium alginate (NaAlg) on the polyacrylonitrile (PAN) support layer. The SEM showed a mutilayer structure and a distinct interface between the HA layer and the NaAlg layer. The coating sequence of two-active-layer had an obvious influence on the pervaporation dehydration performance of membranes. When the operation temperature was 80 °C and water concentration in feed was 10 wt.%, the permeate fluxes of HA/Alg/PAN membrane and Alg/HA/PAN membrane were similar, whereas the separation factor were 1130 and 527, respectively. It was found that the capping layer with higher hydrophilicity and water retention capacity, and the inner layer with higher permselectivity could increase the separation performance of the composite membranes. Meanwhile, effects of operation temperature and water concentration in feed on pervaporation performance as well as membrane properties were studied. Copyright © 2013 Elsevier Ltd. All rights reserved.

Fabrication, ultra-structure characterization and in vitro studies of RF magnetron sputter deposited nano-hydroxyapatite thin films for biomedical applications

NASA Astrophysics Data System (ADS)

Surmeneva, Maria A.; Surmenev, Roman A.; Nikonova, Yulia A.; Selezneva, Irina I.; Ivanova, Anna A.; Putlyaev, Valery I.; Prymak, Oleg; Epple, Matthias

2014-10-01

A series of nanostructured low-crystalline hydroxyapatite (HA) coatings averaging 170, 250, and 440 nm in thickness were deposited onto previously etched titanium substrates through radio-frequency (RF) magnetron sputtering. The HA coatings were analyzed using infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning and transmission electron microscopy (SEM and TEM). Cross sections of the thin specimens were prepared by FIB to study the microstructure of the coatings by TEM. The deposition process formed nano-scale grains, generating an amorphous layer at the substrate/coating interface and inducing the growth of a columnar grain structure perpendicular to the substrate surface. A microstructural analysis of the film confirmed that the grain size and crystallinity increased when increasing the deposition time. The nanostructured HA coatings were not cytotoxic, as proven by in vitro assays using primary dental pulp stem cells and mouse fibroblast NCTC clone L929 cells. Low-crystallinity HA coatings with different thicknesses stimulated cells to attach, proliferate and form mineralized nodules on the surface better than uncoated titanium substrates.

Study on clinical application of nano-hydroxyapatite bone in bone defect repair.

PubMed

Zhu, Weimin; Wang, Daping; Xiong, Jianyi; Liu, Jianquan; You, Wei; Huang, Jianghong; Duan, Li; Chen, Jielin; Zeng, Yanjun

2015-01-01

To study the clinical effect of bone defect treated with nano-hydroxyapatite(Nano-HA) artificial bone. From September 2009 to June 2012, 27 cases of bone defect were analyzed retrospectively. The position of bone defect included humerus, radius, ulna, femur, tibia and calcaneus. The range of bone defect was from 0.3 × 1.0 cm to 3 × 6.5 cm. Among them, there were 22 cases with fractures and 5 cases with tumors. All patients were treated with Nano-HA artificial bone. The ability of bone defect repair was evaluated by X-ray exams performed preoperatively and postoperatively. HSS scores were adopted for final evaluation at the latest follow-up. The patients were followed up from 11 to 26 months (average of 18.5 months). No general side effects occurred. X-ray photo showed an integrity interface between Nano-HA and bone. Primary healing was obtained in all cases without any complication. The Nano-HA artificial bone had a good biocompatibility and could be an ideal artificial bone in the reconstruction of bone defect.

A Refined Model for the TSG-6 Link Module in Complex with Hyaluronan

PubMed Central

Higman, Victoria A.; Briggs, David C.; Mahoney, David J.; Blundell, Charles D.; Sattelle, Benedict M.; Dyer, Douglas P.; Green, Dixy E.; DeAngelis, Paul L.; Almond, Andrew; Milner, Caroline M.; Day, Anthony J.

2014-01-01

Tumor necrosis factor-stimulated gene-6 (TSG-6) is an inflammation-associated hyaluronan (HA)-binding protein that contributes to remodeling of HA-rich extracellular matrices during inflammatory processes and ovulation. The HA-binding domain of TSG-6 consists solely of a Link module, making it a prototypical member of the superfamily of proteins that interacts with this high molecular weight polysaccharide composed of repeating disaccharides of d-glucuronic acid and N-acetyl-d-glucosamine (GlcNAc). Previously we modeled a complex of the TSG-6 Link module in association with an HA octasaccharide based on the structure of the domain in its HA-bound conformation. Here we have generated a refined model for a HA/Link module complex using novel restraints identified from NMR spectroscopy of the protein in the presence of 10 distinct HA oligosaccharides (from 4- to 8-mers); the model was then tested using unique sugar reagents, i.e. chondroitin/HA hybrid oligomers and an octasaccharide in which a single sugar ring was 13C-labeled. The HA chain was found to make more extensive contacts with the TSG-6 surface than thought previously, such that a d-glucuronic acid ring makes stacking and ionic interactions with a histidine and lysine, respectively. Importantly, this causes the HA to bend around two faces of the Link module (resembling the way that HA binds to CD44), potentially providing a mechanism for how TSG-6 can reorganize HA during inflammation. However, the HA-binding site defined here may not play a role in TSG-6-mediated transfer of heavy chains from inter-α-inhibitor onto HA, a process known to be essential for ovulation. PMID:24403066

Photocrosslinked Tyramine-Substituted Hyaluronate Hydrogels with Tunable Mechanical Properties Improve Immediate Tissue‐Hydrogel Interfacial Strength in Articular Cartilage

PubMed Central

Donnelly, Patrick E.; Chen, Tony; Finch, Anthony; Brial, Caroline; Maher, Suzanne A.; Torzilli, Peter A.

2017-01-01

Articular cartilage lacks the ability to self-repair and a permanent solution for cartilage repair remains elusive. Hydrogel implantation is a promising technique for cartilage repair; however for the technique to be successful hydrogels must interface with the surrounding tissue. The objective of this study was to investigate the tunability of mechanical properties in a hydrogel system using a phenol-substituted polymer, tyramine-substituted hyaluronate (TA-HA), and to determine if the hydrogels could form an interface with cartilage. We hypothesized that tyramine moieties on hyaluronate could crosslink to aromatic amino acids in the cartilage extracellular matrix. Ultraviolet (UV) light and a riboflavin photosensitizer were used to create a hydrogel by tyramine self‐crosslinking. The gel mechanical properties were tuned by varying riboflavin concentration, TA-HA concentration, and UV exposure time. Hydrogels formed with a minimum of 2.5 min of UV exposure. The compressive modulus varied from 5–16 kPa. Fluorescence spectroscopy analysis found differences in dityramine content. Cyanine-3 labelled tyramide reactivity at the surface of cartilage was dependent on the presence of riboflavin and UV exposure time. Hydrogels fabricated within articular cartilage defects had increasing peak interfacial shear stress at the cartilage-hydrogel interface with increasing UV exposure time, reaching a maximum shear stress 3.5× greater than a press‐fit control. Our results found that phenol-substituted polymer/riboflavin systems can be used to fabricate hydrogels with tunable mechanical properties and can interface with the surface tissue, such as articular cartilage. PMID:28134036

Synthesis, characterization and modelling of zinc and silicate co-substituted hydroxyapatite

PubMed Central

Friederichs, Robert J.; Chappell, Helen F.; Shepherd, David V.; Best, Serena M.

2015-01-01

Experimental chemistry and atomic modelling studies were performed here to investigate a novel ionic co-substitution in hydroxyapatite (HA). Zinc, silicate co-substituted HA (ZnSiHA) remained phase pure after heating to 1100°C with Zn and Si amounts of 0.6 wt% and 1.2 wt%, respectively. Unique lattice expansions in ZnSiHA, silicate Fourier transform infrared peaks and changes to the hydroxyl IR stretching region suggested Zn and silicate co-substitution in ZnSiHA. Zn and silicate insertion into HA was modelled using density functional theory (DFT). Different scenarios were considered where Zn substituted for different calcium sites or at a 2b site along the c-axis, which was suspected in singly substituted ZnHA. The most energetically favourable site in ZnSiHA was Zn positioned at a previously unreported interstitial site just off the c-axis near a silicate tetrahedron sitting on a phosphate site. A combination of experimental chemistry and DFT modelling provided insight into these complex co-substituted calcium phosphates that could find biomedical application as a synthetic bone mineral substitute. PMID:26040597

THE ELECTROCHEMICAL PROPERTIES OF FOUR DENTAL CASTING SUPRASTRUCTURE ALLOYS COUPLED WITH TITANIUM IMPLANTS

PubMed Central

Tuna, Suleyman Hakan; Pekmez, Nuran Ozcícek; Keyf, Filiz; Canlí, Fulya

2009-01-01

Objectives: As the choice of suprastructure alloy to be combined with titanium for the oral cavity is still a much debated issue, the aim of this study was to investigate the electrochemical interaction of the suprastructure/implant couples under the determined experiment conditions. Material and Methods: The potentiodynamic polarization curves and open-circuit potentials (OCP) of four UCLA type suprastructures coupled with straight Swiss Plus implant fixtures were taken in Afnor type artificial saliva solution at 37°C. The concentration of ions leached into artificial saliva solutions was estimated with ICP-MS. SEM images of the margins of suprastructure/implant couples were obtained before and after the electrochemical tests. Results: The OCP value of titanium became passive at the most negative potential. The lowest difference between the initial and constant OCP value was exhibited by the Au based suprastructure. Suprastructures made greater contributions to the potentiodynamic polarization curves of the implant/suprastructure couples. According to the ICP-MS results, Pd based and Au based couples dissolved less than Co-Ni based and Co-Cr based couples. Conclusions: Within the conditions this study, it may be concluded that the titanium implant forms a stable passive oxide layer in artificial saliva exposed to open air and does not affect the corrosion properties of the suprastructures. Pd based and Au based couples have been found to be more corrosion-resistant than base alloy couples. PMID:19936528

Precursor anion states in dissociative electron attachment to chlorophenol isomers.

PubMed

Kossoski, F; Varella, M T do N

2016-07-28

We report a theoretical study on low-energy (<10 eV) elastic electron scattering from chlorophenol isomers, namely, para-chlorophenol (pCP), meta-chlorophenol (mCP), and ortho-chlorophenol (oCP). The calculations were performed with the Schwinger multichannel method with pseudopotentials, and analysis of the computed integral cross sections and virtual orbitals revealed one σCCl (∗), one σOH (∗), and three π(∗) shape resonances. We show that electron capture into the two lower lying π(∗) orbitals initiates dissociative processes that lead to the elimination of the chloride ion, accounting for the two overlapping peaks where this fragment was observed. Despite the relatively small differences on the energetics of the π(∗) resonances, a major isomeric effect was found on their corresponding autodetachment lifetimes, which accounts for the observed increasing cross sections in the progression pCP < mCP < oCP. In particular, dissociation from the π1 (∗) anion of pCP is largely suppressed because of the unfavorable mixing with the σCCl (∗) state. We found the intramolecular hydrogen bond present in oCP to have the opposite effects of stabilizing the σCCl (∗) resonance and destabilizing the σOH (∗) resonance. We also suggest that the hydrogen abstraction observed in chlorophenols and phenol actually takes place by a mechanism in which the incoming electron is directly attached to the dissociative σOH (∗) orbital.

Aromatase gene polymorphism does not influence clinical phenotype and response to oral contraceptive pills in polycystic ovary syndrome women.

PubMed

Maier, Polyana S; Spritzer, Poli Mara

2012-01-01

To assess whether a single nucleotide polymorphism (SNP50) of the aromatase gene (CYP19) is associated with polycystic ovary syndrome (PCOS) phenotypes and to investigate the influence of this polymorphism on the response of PCOS to treatment with oral contraceptive pills (OCP). 162 hirsute women were stratified into a classic PCOS group (hyperandrogenism, ovulatory dysfunction, c-PCOS) and an ovulatory PCOS group (hyperandrogenism, ovulatory cycles, polycystic ovaries, ov-PCOS). 51 women completed a 6-month OCP trial (20 µg ethinyl estradiol + 75 µg gestodene, 21/28 days per cycle, plus 100 mg spironolactone in 32 women with moderate to severe hirsutism). We considered the presence of the polymorphic allele A (AG+AA) in comparison to the absence of the polymorphism (GG) to express results and to perform the comparisons regarding clinical variables. Mean age was 23.3 ± 6.9 years. Hirsutism score was similar in c-PCOS and ov-PCOS (15 (11-20) vs. 13 (11-20)). The differences in hormone and metabolic variables between phenotypes were independent of the presence of allele A. In the OCP trial subsample, no differences were observed between genotypes after 6 months' treatment. The differences between c-PCOS and ov-PCOS cannot be explained by the genetic variation at SNP50 in the CYP19 gene. Copyright © 2012 S. Karger AG, Basel.

Dual suppression with oral contraceptive pills in GnRH antagonist cycles for patients with polycystic ovary syndrome undergoing intracytoplasmic sperm injection.

PubMed

Ozmen, B; Sükür, Y E; Seval, M M; Ateş, C; Atabekoğlu, C S; Sönmezer, M; Berker, B

2014-12-01

To evaluate the effects of a gonadotropin-releasing hormone (GnRH) antagonist protocol, with or without oral contraceptive pill (OCP) pretreatment, in patients with polycystic ovary syndrome (PCOS) undergoing intracytoplasmic sperm injection (ICSI). In this retrospective cohort study, 410 infertile patients with PCOS were assessed in their first ICSI cycles between January 2006 and June 2013. In Group A (n=208), patients underwent a long luteal GnRH agonist protocol, and in Groups B (n=143) and C (n=59), patients underwent a GnRH antagonist protocol. The patients in Group C also received OCPs containing 30mg of ethinyl oestradiol and 3mg of drospirenone prior to treatment. The main outcome measures were pregnancy and ovarian hyperstimulation syndrome (OHSS) rates. Demographic features, body mass index, duration of infertility, serum baseline hormone levels, cycle outcomes, multiple pregnancy rates, miscarriage rates, OHSS rates, total number of Grade A embryos and total number of transferred embryos were comparable between the groups. Clinical pregnancy rates were 27.4%, 26.6% and 23.7% in Groups A, B and C, respectively (p=0.853). OCP pretreatment was found to have no beneficial or adverse effects in patients with PCOS undergoing a GnRH antagonist protocol for ICSI, but can be used for cycle scheduling. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Spatial trends of organochlorinated pesticides, polychlorinated biphenyls, and polybrominated diphenyl ethers in Atlantic Anguillid eels.

PubMed

Byer, Jonathan D; Lebeuf, Michel; Alaee, Mehran; Stephen, Brown R; Trottier, Steve; Backus, Sean; Keir, Michael; Couillard, Catherine M; Casselman, John; Hodson, Peter V

2013-02-01

The bioaccumulation of lipophilic contaminants such as polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) can result in a reduction in fitness and spawner quality in eels and may be a factor in Anguillid sp. population declines. Contaminant concentrations in eels have been studied extensively in Europe, but data for American eels are severely lacking. Concentrations of PCBs, OCPs, and PBDEs were determined in American eel from eastern Canada and New York, USA, along with European eel from Belgium. Principal component analysis revealed that eels captured in the St. Lawrence estuary were a mixture of upstream migrants from the St. Lawrence River watershed, and fish captured in local tributaries. Contaminant concentrations were dependent on origin, related to the local environment, and were lower than historic values. In Canada, concentrations of OCPs and PCBs in eel tissues were below the Canadian human consumption guidelines for contaminants in fish, indicating that the current risk to consumers is low. However, concentrations of PCBs, total DDT, and mirex in eels from L. Ontario and the upper St. Lawrence R. were above Great Lakes guidelines for the protection of piscivorous predators. Concentrations of penta-BDE homologs exceeded the Canadian guideline for environmental quality in over half of the eels in this study, but concentrations of the other homolog groups were below the guideline. Copyright © 2012 Elsevier Ltd. All rights reserved.