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Potential Source (potential + source)
Kinds of Potential Source Selected AbstractsPETROGRAPHIC AND STABLE ISOTOPE ANALYSES OF LATE CLASSIC ULÚA MARBLE VASES AND POTENTIAL SOURCES*ARCHAEOMETRY, Issue 1 2006C. LUKE Ulúa marble vases from the Ulúa Valley of northwestern Honduras are a hallmark luxury good from Late Classic (ad 600,900) Mesoamerica. Archaeological and stylistic data point to centralized production at one site, Travesía. This paper analyses stable isotope and petrographic data from the vases and three potential procurement areas. The results indicate that the vases were produced from one primary source with one, potentially two, secondary sources. Procurement patterns most probably corresponded to contemporary communication routes. The results clearly indicate that a multi-method approach is necessary for sourcing marble from Honduras. [source] Rock Art: A Potential Source of Information about Past Maritime Technology in the South-East Asia-Pacific RegionINTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 2 2007Peter V. Lape It is possible that most or all boats and rig-types used in prehistoric times in the South-East Asia-Pacific region have completely disappeared from the record, and that those recorded by Europeans in the 17th century may have been relatively recent innovations. The purpose of this paper is to introduce to the literature a new source of information on ancient boat and rig designs. This source is the information encoded in rock-art depictions of watercraft. This paper provides a technical appraisal of 18 images of watercraft from the Tutuala region of East Timor. © 2007 The Authors [source] ChemInform Abstract: 2-Arylethenyl-2,-arylethynyl Sulfones: A Potential Source for Some Spiroheterocycles.CHEMINFORM, Issue 44 2001Dandu Bhaskar Reddy Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Paleosols in Central Illinois as Potential Sources of Ammonium in GroundwaterGROUND WATER MONITORING & REMEDIATION, Issue 4 2009Justin J. G. Glessner Glacially buried paleosols of pre-Holocene age were evaluated as potential sources for anomalously large concentrations of ammonium in groundwater in East Central Illinois. Ammonium has been detected at concentrations that are problematic to water treatment facilities (greater than 2.0 mg/L) in this region. Paleosols characterized for this study were of Quaternary age, specifically Robein Silt samples. Paleosol samples displayed significant capacity to both store and release ammonium through experiments measuring processes of sorption, ion exchange, and weathering. Bacteria and fungi within paleosols may significantly facilitate the leaching of ammonium into groundwater by the processes of assimilation and mineralization. Bacterial genetic material (DNA) was successfully extracted from the Robein Silt, purified, and amplified by polymerase chain reaction to produce 16S rRNA terminal restriction fragment length polymorphism (TRFLP) community analyses. The Robein Silt was found to have established diverse and viable bacterial communities. 16S rRNA TRFLP comparisons to well-known bacterial species yielded possible matches with facultative chemolithotrophs, cellulose consumers, nitrate reducers, and actinomycetes. It was concluded that the Robein Silt is both a source and reservoir for groundwater ammonium. Therefore, the occurrence of relatively large concentrations of ammonium in groundwater monitoring data may not necessarily be an indication of only anthropogenic contamination. The results of this study, however, need to be placed in a hydrological context to better understand whether paleosols can be a significant source of ammonium to drinking water supplies. [source] Aquatic photochemistry of chlorinated triclosan derivatives: Potential source of polychlorodibenzo- P -dioxins,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2009Jeffrey M. Buth Abstract Triclosan (TCS; 5-chloro-2-(2,4-dichlorophenoxy)phenol), a common antimicrobial agent, may react with residual chlorine in tap water during transport to wastewater treatment plants or during chlorine disinfection of wastewater, generating chlorinated TCS derivatives (CTDs): 4,5-dichloro-2-(2,4-dichlorophenoxy)phenol (4-Cl-TCS), 5,6-dichloro-2-(2,4-dichlorophenoxy)phenol (6-C1-TCS), and 4,5,6-trichloro-2-(2,4-dichlorophenoxy)phenol (4,6-Cl-TCS). The photochemistry of CTDs was investigated due to the potential formation of polychlorodibenzo- p -dioxin (PCDD) photoproducts. Photolysis rates were highly dependent upon CTD speciation, because the phenolate species degraded 44 to 586 times faster than the phenol forms. Photolysis quantum yield values for TCS, 4-Cl-TCS, 6-Cl-TCS, and 4,6-Cl-TCS of 0.39, 0.07, 0.29, and 0.05, respectively, were determined for the phenolate species. Photolyses performed in Mississippi River and Lake Josephine (USA) waters gave similar quantum yields as buffered, pure water at the same pH, indicating that indirect photolysis processes involving photosensitization of dissolved organic matter are not competitive with direct photolysis. The photochemical conversion of the three CTDs to PCDDs under solar irradiation was confirmed in natural and buffered, pure water at yields of 0.5 to 2.5%. The CTD-derived PCDDs possess higher toxicities than 2,8-dichlorodibenzo- p -dioxin, a previously identified photoproduct of TCS, due to their higher chlorine substitution in the lateral positions. The load of TCS- and CTD-derived PCDDs to United States surface waters is estimated to be between 46 and 92 g toxicity equivalent units per year. Other identified photoproducts of each CTD were 2,4-dichlorophenol and reductive dechlorination products. [source] Outcome of primary root canal treatment: systematic review of the literature , Part 2.INTERNATIONAL ENDODONTIC JOURNAL, Issue 1 2008Influence of clinical factors Abstract Aims, (i) To carry out meta-analyses to quantify the influence of the clinical factors on the efficacy of primary root canal treatment and (ii) to identify the best treatment protocol based on the current evidence. Methodology, The evidence for the effect of each clinical factor on the success rate (SR) of primary root canal treatment was gathered in three different ways: (i) intuitive synthesis of reported findings from individual studies; (ii) weighted pooled SR by each factor under investigation was estimated using random-effect meta-analysis; (iii) weighted effect of the factor under investigation on SR were estimated and expressed as odds ratio for the dichotomous outcomes (success or failure) using fixed- and random-effects meta-analysis. Statistical heterogeneity amongst the studies was assessed by Cochran's (Q) test. Potential sources of statistical heterogeneity were investigated by exploring clinical heterogeneity using meta-regression models which included study characteristics in the regression models. Results, Out of the clinical factors investigated, pre-operative pulpal and periapical status were most frequently investigated, whilst the intra-operative factors were poorly studied in the 63 studies. Four factors were found to have a significant effect on the primary root canal treatment outcome, although the data heterogeneity was substantial, some of which could be explained by some of the study characteristics. Conclusions, Four conditions (pre-operative absence of periapical radiolucency, root filling with no voids, root filling extending to 2 mm within the radiographic apex and satisfactory coronal restoration) were found to improve the outcome of primary root canal treatment significantly. Root canal treatment should therefore aim at achieving and maintaining access to apical anatomy during chemo-mechanical debridement, obturating the canal with densely compacted material to the apical terminus without extrusion into the apical tissues and preventing re-infection with a good quality coronal restoration. [source] Potential sources of food hazards in emerging commercial aquaculture industry in sub-Saharan Africa: a case study for UgandaINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 9 2009Ananias Bagumire Summary A study was conducted to assess sources of food hazards in Uganda's emerging commercial aquaculture industry based on Hazard Analysis Critical Control Point (HACCP), focusing on inputs, their sources and farm-practices on ten representative commercial farms. Critical control points (CCPs) were identified to reveal potential hazards that would jeopardise any export trade. Site selection, water quality, fertiliser, fish seed, fish rearing facilities, feeds, and post-harvest practices were the main CCPs identified. Animal manure was used to generate plankton as pond fertiliser in nine of the ten surveyed farms and veterinary drugs were not found in any of the ten farms, which is starkly different from aquaculture in indutrialised countries. Potential sources of hazards from water were mainly: municipal waste flow which was more likely on five of the ten farms, domestic waste (four farms), agricultural run-off (three farms), and low water pH (three farms). Fish fry and fingerlings from other farms, feeds formulated on-farm from unapproved sources, chemical products, uncontrolled fish predators, and domestic animal and human activities were the other potential sources of hazards. A complete application of HACCP is recommended for producing safe products that meet the strict market standards of developed countries. [source] Direct comparison of four bacterial source tracking methods and use of composite data setsJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2007E.A. Casarez Abstract Aims:, Four bacterial source tracking (BST) methods, enterobacterial repetitive intergenic consensus sequence polymerase chain reaction (ERIC-PCR), automated ribotyping using HindIII, Kirby-Bauer antibiotic resistance analysis (KB-ARA) and pulsed-field gel electrophoresis (PFGE) were directly compared using the same collection of Escherichia coli isolates. The data sets from each BST method and from composite methods were compared for library accuracy and their ability to identify water isolates. Methods and Results:, Potential sources of faecal pollution were identified by watershed sanitary surveys. Domestic sewage and faecal samples from pets, cattle, avian livestock, other nonavian livestock, avian wildlife and nonavian wildlife sources were collected for isolation of E. coli. A total of 2275 E. coli isolates from 813 source samples were screened using ERIC-PCR to exclude clones and to maximize library diversity, resulting in 883 isolates from 745 samples selected for the library. The selected isolates were further analysed using automated ribotyping with HindIII, KB-ARA and PFGE. A total of 555 E. coli isolates obtained from 412 water samples were analysed by the four BST methods. A composite data set of the four BST methods gave the highest rates of correct classification (RCCs) with the fewest unidentified isolates than any single method alone. RCCs for the four-method composite data set and a seven-way split of source classes ranged from 22% for avian livestock to 83% for domestic sewage. Two-method composite data sets were also found to be better than individual methods, having RCCs similar to the four-method composite and identification of the same major sources of faecal pollution. Conclusions:, The use of BST composite data sets may be more beneficial than the use of single methods. Significance and Impact of the Study:, This is one of the first comprehensive comparisons using composite data from several BST methods. While the four-method approach provided the most desirable BST results, the use of two-method composite data sets may yield comparable BST results while providing for cost, labour and time savings. [source] Potential sources of background contaminants in solid phase extraction and microextractionJOURNAL OF SEPARATION SCIENCE, JSS, Issue 7 2007Robert Stiles Abstract A study to identify the sources of background contamination from SPE, using a C-18 sorbent, and solid-phase microextraction (SPME), using a 70 ,m carbowax/divinylbenzene (CW/DVB) fiber, was carried out. To determine the source of contamination, each material used in the procedure was isolated and examined for their contribution. The solid-phase column components examined were: sorbent material and frits, column housings and each solvent used to elute analytes off the column. The components examined in the SPME procedure were: SPME fiber, SPME vials, water (HPLC grade), and salt (sodium chloride) used to increase the ionic strength. The majority of the background contaminants from SPE were found to be from the SPE sorbent material and frits. The class of contaminants extracted during a blank extraction were phthalates and other plasticizers used during the manufacturing process. All had blank levels corresponding to measured concentrations below 2 ng/mL, except for undecane, which had a concentration of 5.4 ng/mL. The most prevalent contaminants in the SPME blank procedure are 1,9-nonanediol, a mixture of phthalates and highly bis- substituted phenols. All the concentrations were below 2 ng/mL, with the exception of bis (2-ethylhexyl) phthalate, which had concentrations ranging from 5 to 20 ng/mL. [source] A new paradigm in cell therapy for diabetes: Turning pancreatic ,-cells into ,-cellsBIOESSAYS, Issue 10 2010Caroline B. Sangan Cell therapy means treating diseases with the body's own cells. One of the cell types most in demand for therapeutic purposes is the pancreatic ,-cell. This is because diabetes is one of the major healthcare problems in the world. Diabetes can be treated by islet transplantation but the major limitation is the shortage of organ donors. To overcome the shortfall in donors, alternative sources of pancreatic ,-cells must be found. Potential sources include embryonic or adult stem cells or, from existing ,-cells. There is now a startling new addition to this list of therapies: the pancreatic ,-cell. Thorel and colleagues recently showed that under circumstances of extreme pancreatic ,-cell loss, ,-cells may serve to replenish the insulin-producing compartment. This conversion of ,-cells to ,-cells represents an example of transdifferentiation. Understanding the molecular basis for transdifferentiation may help to enhance the generation of ,-cells for the treatment of diabetes. [source] Cyclotron: a secure, isolated, virtual cycle-scavenging grid in the enterpriseCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 3 2010Kevin Kane Abstract Cycle-scavenging grids appeal to organizations with large numbers of workstations that remain idle outside of normal working hours. This represents a potential source of grid computing cycles, but the security and isolation issues that come with the use of non-dedicated resources have slowed their adoption in the enterprise. In this paper we present Cyclotron, a prototype cycle-scavenging grid solution that leverages virtualization and a declarative security policy-based access control infrastructure, supporting flexible authorization rules and the constrained delegation of access rights, to address these requirements. Copyright © 2009 John Wiley & Sons, Ltd. [source] Prevention of Nosocomial Infection During Dermoscopy?DERMATOLOGIC SURGERY, Issue 4 2006SUSAN C. KELLY DO BACKGROUND Dermatoscopes are applied directly to cutaneous or mucocutaneous surfaces with immersion fluid (IF) such as oil or alcohol to reduce light reflection. Recently, Staphylococcus aureus has been isolated from dermatosopes that used mineral oil as the IF. Thus, dermatoscopes might be a potential source of nosocomial infection. OBJECTIVE In this study we propose the use of an alcohol-based antibacterial gel to reduce nosocomial infection transmission while optimizing optical resolution during dermatoscopic examination. MATERIALS AND METHODS Aerobic bacterial cultures were performed on three dermatoscopes used in an outpatient setting after routine examination of 31 patients with an alcohol-based antibacterial gel as IF. RESULTS There was no bacterial growth after using the antibacterial gel with the dermatoscopes. The optical resolution for the antibacterial gel appeared equal to the ,dermatoscopy oil' and superior to alcohol wipes. CONCLUSIONS Alcohol-based antibacterial gel appears to inhibit bacterial colonization while offering excellent optical resolution during dermoscopic examination. The use of alcohol-based IF appears to obviate the risk of nosocomial infections. [source] Progenitor cells in the adult pancreasDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 1 2004Andrew M. Holland Abstract The ,-cell mass in the adult pancreas possesses the ability to undergo limited regeneration following injury. Identifying the progenitor cells involved in this process and understanding the mechanisms leading to their maturation will open new avenues for the treatment of type 1 diabetes. However, despite steady advances in determining the molecular basis of early pancreatic development, the identification of pancreatic stem cells or ,-cell progenitors and the molecular mechanisms underlying ,-cell regeneration remain unclear. Recent advances in the directed differentiation of embryonic and adult stem cells has heightened interest in the possible application of stem cell therapy in the treatment of type 1 diabetes. Drawing on the expanding knowledge of pancreas development, ,-cell regeneration and stem cell research, this review focuses on progenitor cells in the adult pancreas as a potential source of ,-cells. Copyright © 2004 John Wiley & Sons, Ltd. [source] Nipple aspirate fluid and ductoscopy to detect breast cancerDIAGNOSTIC CYTOPATHOLOGY, Issue 4 2010Edward R. Sauter M.D., Ph.D. Abstract We prospectively performed cytologic assessment and image analysis (IA) on matched nipple aspirate fluid (NAF) and mammary ductoscopy (MD) specimens to determine (1) the accuracy of these methods in cancer detection and (2) whether the two collection methods provide complementary information. NAF and MD specimens were collected from 84 breasts from 75 women (nine bilateral samples) who underwent breast surgery. Cytologic evaluation was performed on all samples. IA was performed on slides with sufficient epithelial cells. Cytologic evaluation proved more accurate in patients without pathologic spontaneous nipple discharge (PND) than those with PND, mainly because of the potential false positive diagnosis in the latter. While the sensitivity of NAF and MD cytology was low (10% and 14%, respectively), both were 100% specific in cancer detection in the non-PND cohort. Combining NAF and MD cytology information improved sensitivity (24%) without sacrificing specificity. Similar to cytology, IA was more accurate in patients without PND having high specificity (100% for aneuploid IA), but relatively low sensitivity (36%). Combining NAF and MD cytology with aneuploid IA improved the sensitivity (45%) while maintaining high specificity (100%). The best predictive model was positive NAF cytology and/or MD cytology combined with IA aneuploidy, which resulted in 55% sensitivity and 100% specificity in breast cancer detection. Cytologic evaluation and IA of NAF and MD specimens are complementary. The presence of atypical cells arising from an intraductal papilloma in ductoscopic specimens is a potential source of false positive diagnosis in patients with nipple discharge. Diagn. Cytopathol. 2010 © 2009 Wiley-Liss, Inc. [source] Inferring historical introduction pathways with mitochondrial DNA: the case of introduced Argentine ants (Linepithema humile) into New ZealandDIVERSITY AND DISTRIBUTIONS, Issue 5 2007Steve E. Corin ABSTRACT The threat imposed by invasive species and difficulties associated with control and management places more impetus on trying to prevent their introduction. The identification of introduction pathways is a vital component towards this goal. In this study, we use a genetic marker-based approach to retrospectively investigate the pathway of origin of the invasive Argentine ant (Linepithema humile) into New Zealand. We intensively sample the mitochondrial gene cytochrome b, from the entire known range of Argentine ants in New Zealand. No genetic variation was found in New Zealand. In order to identify likely introduction pathways, we use two alternative genetic analyses and suggest that a tcs approach that collapses identical haplotypes and calculates the probability of parsimony is superior to standard phylogenetic tree-building algorithms. A minimum spanning network allowed relationships to be examined among sequences collated from previous international studies. The cytochrome b sequence, when compared to a global database, matched that from an Australian population. That Australia is the potential source of Argentine ants is in agreement with the New Zealand interception record, as goods from Australia have the highest number of interception records of Argentine ants. Our approach can easily be duplicated for other organisms and the methodology can be more widely applied to help aid further efforts to identify the routes of transmission for other invasive species and allow us to efficiently direct our biosecurity monitoring effort. [source] The significance of overlapping plant range to a putative adaptive trade-off in the black bean aphid Aphis fabae ScopECOLOGICAL ENTOMOLOGY, Issue 4 2004C. R. Tosh Abstract., 1. This study continues to explore the analysis of a putative adaptive trade-off in the utilisation of host plants Vicia faba and Tropaeolum majus by the aphid, Aphis fabae. These plants are utilised exclusively by the subspecies Aphis fabae fabae and A. f. mordwilkoi respectively, and this plant-use system has been studied previously as a potential source of disruptive selection. 2. Here the potential of these two host plants to generate disruptive selection is considered given common utilisation of the abundant host plant, Rumex obtusifolius, by both subspecies. 3. The life history of subspecific clones is quantified in the laboratory on V. faba, T. majus, and R. obtusifolius at various temperatures and used to parameterise a temperature-driven simulation model of aphid population development. 4. Accuracy of the model is tested using a field experiment, and fitness of clones on specific and common host is simulated using temperature data from a number of English sites. 5. The model gives a close quantitative fit to field data and makes the following predictions: performance of A. f. fabae is higher on the specific host than the common host under all tested thermal regimes; and performance of A. f. mordwilkoi is superior on the specific host in warm years but inferior in cold years. 6. Given the great abundance of R. obtusifolius relative to T. majus, the model predicts that the plant utilisation system has little potential to consistently promote hybrid dysfunction. This adds further weight to the assertion that the plant utilisation system studied can offer little insight into the evolutionary processes involved in subspecific differentiation and probably contains a host plant/host plants acquired after the evolution of reproductive barriers. [source] Firm-Specific Human Capital and Governance in IPO Firms: Addressing Agency and Resource Dependence ConcernsENTREPRENEURSHIP THEORY AND PRACTICE, Issue 4 2009Jonathan D. Arthurs Entrepreneurs with firm-specific human capital represent both a potential source of competitive advantage and a threat to appropriate the rents that are ultimately generated by a new venture. This situation presents interesting agency and resource dependence challenges. While potential investors in these ventures will want assurances that their interests are protected, they will also want to ensure that these key entrepreneurs remain with the organization. Using agency theory and resource dependence theory, we examine the types of governance mechanisms that are implemented in firms going through an initial public offering comparing those ventures which indicate a dependence on these critical entrepreneurs versus those that do not. Our analysis reveals that ventures exhibiting dependence on key entrepreneurs are associated with higher insider and outsider ownership by the board, greater start-up experience by the board, greater use of contingent compensation, and greater use of involuntary departure agreements. [source] DNA damage in Pakistani pesticide-manufacturing workers assayed using the Comet assayENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 8 2006Javed A. Bhalli Abstract The production and use of chemical pesticides has increased in recent years. Although the increased use of pesticides may benefit agriculture, they are also the potential source of environmental pollution, and exposure to pesticides can have negative consequences for human health. In the present study, we have assessed DNA damage in blood leukocytes from 29 Pakistani pesticide-factory workers and 35 controls of similar age and smoking history. The workers were exposed to various mixtures of organophosphates, carbamates, and pyrethroids. DNA damage was measured with the single cell gel electrophoresis (SCGE) assay or Comet assay, using the mean comet tail length (,m) as the DNA damage metric. Exposed workers had significantly longer comet tail lengths than the controls (mean ± SD 19.98 ± 2.87 vs. 7.38 ± 1.48, P < 0.001). Of the possible confounding factors, smokers had significantly longer mean comet tail lengths than nonsmokers and exsmokers for both the workers (21.48 ± 2.58 vs.18.37 ± 2.28, P < 0.001) and the controls (8.86 ± 0.56 vs. 6.79 ± 1.31, P < 0.001), while age had a minimal effect on DNA damage (P > 0.05 and P < 0.05 for workers and controls, respectively). The results of this study indicate that occupational exposure to pesticides causes DNA damage. Environ. Mol. Mutagen., 2006. © 2006 Wiley-Liss, Inc. [source] Persistent organochlorine residues and their bioaccumulation profiles in resident and migratory birds from North VietnamENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2002Tu Binh Minh Abstract Concentrations of persistent organochlorines (OCs), such as polychlorinated biphenyls (PCBs), 1 1,1-trichloro-2,2-bis(p -chlorophenyl)ethane (DDT) and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), and chlordane compounds (CHLs), were determined in whole-body homogenates of resident and migratory birds collected from the Red River estuary, North Vietnam, during March and October 1997. Contamination pattern was in the order of DDTs > PCBs > HCHs > CHLs > HCB in both resident and migratory birds. Residue concentrations, according to the feeding habit, showed little variability, which may reflect relatively similar trophic levels of the bird species analyzed. Resident birds accumulated greater concentrations of DDTs as compared to migrants. In contrast, HCH residues were greater in migratory species. Higher proportions of p,p,-DDT to total DDT concentrations were found in many species of residents and migrants, indicating recent exposure to technical DDT in northern Vietnam. Congener-specific PCB analysis showed the predominance of penta- and hexachlorobiphenyls in all the species analyzed. Estimation of hepatic microsomal enzyme activities suggested higher metabolic capacity for PCB congeners in shore birds from Vietnam as compared to higher-trophic predator birds and marine mammals. Comparison of OC residues in avian species in Asia-Pacific revealed that DDT residues in resident birds in North Vietnam are among the highest values reported for the countries surveyed, suggesting recent usage of DDT in Vietnam. Available data for birds, fish, and bivalves from the recent Asia-Pacific Mussel Watch Program suggested that Vietnam might be a potential source of DDT contamination in Asian developing countries. To our knowledge, this is the first study of the OC accumulation in avian species from Vietnam. [source] Sediment chemical contamination and toxicity associated with a coastal golf course complex,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2001Michael A. Lewis Abstract The increasing density of golf courses represents a potential source of sediment contamination to nearby coastal areas, the chemical and biological magnitude of which is almost unknown. The objective of this study was to determine the concentrations of contaminants and toxicities of sediments impacted by a coastal golf course complex. Sediment contaminant concentrations were determined at least twice during the two-year study period at 14 sampling stations. In addition, a combination of acute and chronic bioassays were conducted exposing four invertebrate test species to whole sediments and associated pore waters. Overall, the Florida, USA, golf course complex had a measurable impact on sediment chemical quality, particularly in near-field areas. Higher concentrations of several trace metals and organochlorine pesticides were detected in many golf course-associated sediments compared with reference areas; however, concentrations decreased seaward and only a few, primarily chlorinated pesticides, exceeded proposed sediment quality guidelines. Chromium, zinc, and mercury were detected more frequently than other trace metals. The DDT and associated metabolites, dieldrin and chlordane, were the more commonly detected organic contaminants. Acute toxicity was uncommon and occurred consistently for sediment collected from one coastal location. In contrast, chronic toxicity occurred at several study sites based on the response of Mysidopsis bahia. It was concluded that the impact of golf course runoff on sediment quality may be subtle and sensitive biological assessment methods, such as chronic toxicity tests, will be needed to detect adverse effects. [source] Gemcitabine induced digital ischaemia and necrosisEUROPEAN JOURNAL OF CANCER CARE, Issue 3 2010A. HOLSTEIN md HOLSTEIN A., BÄTGE R. & EGBERTS E.-H. (2010) European Journal of Cancer Care19, 408,409 Gemcitabine induced digital ischaemia and necrosis A 70-year-old woman presented with a 7-day history of severe pain, paresthesia, oedema, acrocyanosis and punctate haemorrhagic lesions on her fingertips. The complaints began 2 days after the second cycle of a first-line chemotherapy consisting of cisplatin or carboplatin, and gemcitabine due to advanced urothelial carcinoma. At the fingertips of both hands, haemorrhagic and partly ulcerative lesions were found; these were attributed to vascular toxicity of gemcitabine. Therapeutically sympathicolysis by bilateral blockade of the brachial plexus was performed, accompanied by intravenous administration of the prostacyclin analog iloprost, fractionated heparin subcutaneously and oral therapy with corticosteroids and aspirin. Digital amputation could be avoided. Acral ischemia is a rare but probably underreported adverse effect of gemcitabine therapy and a potential source of misdiagnosis. [source] Generation of a Hydroperoxidochromium Complex from Nitratochromium(III) Ions and Hydrogen PeroxideEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 30 2008Mingming Cheng Abstract Accelerated substitution at chromium(III) in CraqONO22+ provides the basis for a novel route to the corresponding hydroperoxidochromium complex in aqueous solutions. Despite the great concentration advantage of water, the reaction of CraqONO22+ with 10,100 mM H2O2 generates >50,% yields of CraqOOH2+, which makes this reaction useful for preparative purposes, and may also represent a potential source of high-valent chromium in biological environments. In a minor, parallel path, small concentrations of a superoxidochromium(III) complex, CraqOO2+, are also produced. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Policosanol characterization and accumulation during ripening of Tunisian Olea europaea,L. fruitsEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 3 2010Faouzi Sakouhi Abstract Policosanol is a mixture of bioactive molecules shown to have beneficial effects in treating hypercholesterolemia. Food products enriched in policosanol are currently available in the US market. In the present study, eight policosanol components were identified by GC-MS during the ripening of Meski olives. The quantitative characterization of these compounds was performed using GC-FID. The results showed that the maximum level of total policosanol components (947.20,mg/100,g oil) was reached at the 26th week after the flowering date of Meski olives. Hexacosanol and tetracosanol were the predominant policosanol components at Meski olive maturity. However pentacosanol, heptacosanol and tricosanol were less present in the olives and they accounted for 14% of the total policosanol at complete maturity of the fruit. The total policosanol content of Meski olives was higher than that of beeswax and whole sugar cane, which belong to the sources of dietary supplements containing policosanol. These findings indicate that olive is a potential source of these health-enhancing compounds for functional foods and nutraceutical applications. [source] Chemical evaluation of some paprika (Capsicum annuum L.) seed oilsEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 12 2009Bertrand Matthäus Dr. Abstract The oil contents of seeds from paprika (Capsicum annuum L.) collected from different locations in Turkey and Italy varied in a relatively wide range from 8.5,g/100,g to 32.6,g/100,g. The fatty acid, tocopherol and sterol contents of the oils from different paprika seeds were investigated. The main fatty acids in paprika seed oils were linoleic acid (69.5,74.7,g/100,g), oleic acid (8.9,12.5,g/100,g) and palmitic acid (10.7,14.2,g/100,g). The oils contained an appreciable amount of ,-tocopherol (306.6,602.6,mg/kg), followed by ,-tocopherol (7.3,148.7,mg/kg). The major sterols were ,-sitosterol (1571.4,4061.7,mg/kg), campesterol (490.8,1182.7,mg/kg), and ,5 -avenasterol (374.5,899.6,mg/kg). The total concentration of sterols ranged from 3134.0,mg/kg to 7233.7,mg/kg. Remarkable amounts of cholesterol were found in the different samples (164.6,491.0,mg/kg). The present study showed that paprika seeds are a potential source of valuable oil that could be used for edible and industrial applications. [source] Recruiting new neurons from the subventricular zone to the rat postnatal cortex: an organotypic slice culture modelEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2008A. G. Dayer Abstract The neurogenic subventricular zone (SVZ) of the lateral ventricle is a potential source for neuronal replacement in the postnatal or adult neocortex after injury. Here we present a novel model system to directly explore the cellular mechanisms of this process. In order to visualize directed migration from the SVZ towards the cortex, we transplanted green fluorescent protein-labeled progenitor/stem cells into the SVZ of newborn rats. At 2 days after transplantation, we generated organotypic slice cultures and applied fluorescent time-lapse imaging to explore directly the migration and integration of donor cells into the host tissue for up to 2 weeks. Our studies revealed that subventricular grafts provide a significant number of immature neurons to neocortical regions. In the cortex, immature neurons first migrate radially towards the pial surface and then differentiate into GABAergic interneurons. We conclude that our model system presents a novel and effective experimental paradigm to evaluate the recruitment of SVZ-derived neurons into the postnatal cortex, a phenomenon that may represent a potential route for cortical repair. [source] Neurosphere generation from dental pulp of adult rat incisorEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2008Ryo Sasaki Abstract Dental pulp is a potential source of cells that can be used in cell replacement therapy for various nervous system disorders. Here we report that adult rat dental pulp cells have the ability to form neurospheres when cultured in serum-free culture medium on super-hydrophilic plates. The cells within small spheres continued to grow, and the dental pulp-derived cells generated large spheres. Sphere formation was dependent on exogenously supplied basic-fibroblast growth factor, but not on epidermal growth factor, and the formation and growth of dental pulp-derived spheres were negatively regulated by transforming growth factor-,. Plating cells that were dissociated from spheres on an adhesive substrate resulted in differentiation into Tuj1- and MAP2-positive neuronal cells. Analysis of the three-dimensional structure of dental pulp-derived spheres shows that they contained nestin-positive progenitors, Tuj1-positive neuronal cells and S100-positive glial cells. We found that spheres contained CD81 (TAPA1) and nestin double-positive cells, and identified a small population of CD81 and nestin double-positive cells in the odontoblast layer of the dental pulp. Flow cytometric analysis showed that CD81-positive cells were enriched in the spheres compared with the dental pulp tissue. Bromodeoxyuridine (BrdU) staining showed that nestin- and BrdU-positive cells were located only in the apical portion of the dental pulp, and the apical portion produced a large number of large-sized spheres. These data suggest that the CD81 and nestin double-positive cells localized in the odontoblast layer of the apical portion of the dental pulp may have the ability to grow and form neurospheres. [source] Non-participation and adjustment for bias in case,control studies of periodontitisEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 5 2008Rodrigo López Periodontal researchers frequently use case,control studies, but information on participation rates and the reasons for participation are often missing in the publications, thus hindering the assessment of the validity of those studies. A nested case,control study based on a well-defined population was used to (i) describe the patterns of participation; (ii) show how some associations can be biased; and (iii) illustrate how inverse probability weights can be applied to reduce bias. Differential subject participation was quantified using the ratio between participation for each level and the overall participation. Possible biased associations were illustrated using the odds ratios found for eligible and participant subjects. Finally, we used the estimated probability that an individual participates in the case,control study conditional on that individual's covariate pattern, as observed in the screening study to attempt bias reduction. Considerable differential participation was observed for selected factors, including age, annual tuitions and fees, parental income, and parental education. The strategy used for adjustment of bias resulted in some degree of bias reduction. These findings challenge the inferential validity of many studies on periodontitis. The design and conduct of these studies should aim to improve subject participation and must consider and minimize this potential source of bias. [source] Alternatively activated macrophages (M2 macrophages) in the skin of patient with localized sclerodermaEXPERIMENTAL DERMATOLOGY, Issue 8 2009Nobuyo Higashi-Kuwata Abstract:, Localized scleroderma is a connective tissue disorder that is limited to the skin and subcutaneous tissue. Macrophages have been reported to be particularly activated in patients with skin disease including systemic sclerosis and are potentially important sources for fibrosis-inducing cytokines, such as transforming growth factor ,. To clarify the features of immunohistochemical characterization of the immune cell infiltrates in localized scleroderma focusing on macrophages, skin biopsy specimens were analysed by immunohistochemistry. The number of cells stained with monoclonal antibodies, CD68, CD163 and CD204, was calculated. An evident macrophage infiltrate and increased number of alternatively activated macrophages (M2 macrophages) in their fibrotic areas were observed along with their severity of inflammation. This study revealed that alternatively activated macrophages (M2 macrophages) may be a potential source of fibrosis-inducing cytokines in localized scleroderma, and may play a crucial role in the pathogenesis of localized scleroderma. [source] Angiotensin AT1 Receptor Antagonist Losartan and the Defence Reaction in the Anaesthetised Rat.EXPERIMENTAL PHYSIOLOGY, Issue 3 2003Effect on the Carotid Chemoreflex Modulation at the level of the nucleus tractus solitarii (NTS) appears to be an effective way of controlling cardiovascular reflexes. Angiotensin II acting on angiotensin AT1 receptors at the central nervous system appears to have an important role in these modulatory processes. The hypothalamic defence area (HDA) is a potential source of descending fibres containing angiotensin II that innervate the NTS. We investigated the effect of AT1 receptor blockade in the NTS on the response to stimulation of HDA in anaesthetised rats treated with the neuromuscular blocking agent pancuronium bromide. The characteristic increase in heart rate, blood pressure and phrenic nerve activity evoked by electrical stimulation of HDA is decreased by the microinjection of the AT1 receptor antagonist losartan into the NTS and the cardiovascular response to carotid body chemical stimulation is also reduced. These results support the hypothesis that AT1 receptors in the NTS play a role in the modulation of cardiovascular reflexes, and modify the influence exerted on the processing of these reflexes by other areas of the central nervous system. [source] Burkholderia anthina sp. nov. and Burkholderia pyrrocinia, two additional Burkholderia cepacia complex bacteria, may confound results of new molecular diagnostic toolsFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2002Peter Vandamme Abstract Nineteen Burkholderia cepacia -like isolates of human and environmental origin could not be assigned to one of the seven currently established genomovars using recently developed molecular diagnostic tools for B. cepacia complex bacteria. Various genotypic and phenotypic characteristics were examined. The results of this polyphasic study allowed classification of the 19 isolates as an eighth B. cepacia complex genomovar (Burkholderia anthina sp. nov.) and to design tools for its identification in the diagnostic laboratory. In addition, new and published data for Burkholderia pyrrocinia indicated that this soil bacterium is also a member of the B. cepacia complex. This highlights another potential source for diagnostic problems with B. cepacia -like bacteria. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||