938 resultados para Phase-Ii


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Many dietary factors have been associated with a decreased risk of developing cancer. One potential mechanism by which these factors, chemopreventors, protect against cancer may be via alteration of carcinogen metabolism. The broccoli constituent sulforaphane (1-isothiocyanate-4-methylsulinylbutane) (CH3-S0-(CH2)4-NCS) has been isolated as a potential inducer of phase II detoxification enzymes and also protects rodents against 9,10-dimethyl-1,2-benz[aJanthracene-induced mammary tumours. The ability of sulforaphane to also modulate phase I activation enzymes (cytochrome P450) (CYP450) was studied here. Sulforaphane was synthesised with an overall yield of 15%, essentially via 1-methylsulfinylphthalimidobutane, which was oxidised to the sulfoxide moiety. Deprotective removal of phthalimide yielded the amine, which was converted into sulforaphane by reaction with N,N'-thionocarbonyldiimidazole. Purity (95 %) was checked by 1H-NMR,13C-NMR and infrared and mass spectrometry.Sulforaphane was a competitive inhibitor of CYP2E1 in acetone-induced Sprague-Dawley rat microsomes (Ki 37.9 ± 4.5μM), as measured by the p-nitrophenol hydroxylase assay. Ethoxyresorufin deethylase activity (EROD), a measurement of CYP1A activity, was also inhibited by sulforaphane (100μM) but was not competitive, and a preincubation time-dependence was observed. In view of these results, the capacity of sulforaphane to inhibit N-nitrosodimethylamine (NDMA)-induced genotoxicity (CYP2E1-mediated) was studied using mouse liver activation systems. Sulforaphane (>0.8μM) inhibited the mutagenicity of NDMA (4.4 mg/plate) in Salmonella typhimurium strain TA100 after pre-incubation for 45 min with acetone-induced liver 9000 g supernatants from Balb/c mice. Unscheduled DNA synthesis induced by NDMA (33μ5 M) in mouse hepatocytes was also reduced by sulforaphane in a concentration-dependent manner (0.064-20μM). Sulforaphane was not genotoxic itself in any of these systems and cytotoxic only at high concentrations (>0.5 mM and > 40μM respectively). The ability of sulforaphane to modulate the orthologous human enzymes was studied using a human epithelial liver cell line (THLE) expressing individual human CYP450 isoenzymes. Using the Comet assay (a measurement of DNA strand breakage under alkaline conditions), NDMA (0.01-1μg/ml) and IQ (0.1-10μg/ml) were used to produce strand breaks in T5-2E1 cells (expressing human CYP2E1) and T5-1A2 cells (expressing human CYP1A2) respectively, however no response was observed in T5-neo cells (without CYP450 cDNA transfection). Sulforaphane inhibited both NDMA and IQ-induced DNA strand breakage in a concentration-dependent manner (0.1-10μM).The inhibition of metabolic activation as a basis for the antigenotoxic action of sulforaphane in these systems (bacteria, rodent hepatocytes and human cells) is further supported by the lack of this chemopreventor to influence NaN3 mutagenicity in S. typhimurium and H202-induced DNA strand breakage in T5-neo cells. These findings suggest that inhibition of CYP2E1 and CYP1A by sulforaphane may contribute to its chemoprotective potential.

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In vitro toxicity tests which detect evidence of the formation of reactive metabolites have previously relied upon cell death as a toxicity end point. Therefore these tests determine cytotoxicity in terms of quantitative changes in specified cell functions. In the studies involving the CaC0-2 cell model, there was no significant change in the transport of [3H] L-proline by the cell after eo-incubation with either dapsone or cyclophosphamide (50µM) and rat liver microsomal metabolite generating system. The pre incubation of the cells with N-ethylmalemide to inhibit Phase II sulphotransferase activity, prior to the microsomal incubations, resulted in cytotoxcity in all incubation groups. Studies involving the L6 cell model showed that there was no significant effect in the cell signalling pathway producing the second messenger cAMP, after incubation with dapsone or cyclophosphamide (50µM) and the rat microsomal metabolite generating system. There was also no significant affect on the vasopressin stimulated production of the second messenger IP3, after incubation with the hydroxylamine metabolite of dapsone, although there were some morphological changes observed with the cells at the highest concentration of dapsone hydroxylamine (100µM). With the test involving the NG115-401 L-C3 cell model, there was no significant changes in DNA synthesis in terms of [3H] thymidine incorporation, after eo-incubation with either phenytoin or cyclophosphamide (50µM) and the rat microsomal metabolite generating system. In the one compartment erythrocyte studies, there were significant decreases in glutathione with cyclophosphamide (50µM) (0.44 ± 0.04 mM), sulphamethoxazole (50µM) (0.43 ± 0.08mM) and carbamazepine (50µM) (0.47 ± 0.034 mM), when eoincubated with the rat microsomal system, compared to the control (0.52 ± 0.07mM). There was no significant depletion in glutathione when the erythrocytes were eoincubated with phenytoin and the rat microsomal system. In the two compartment erythrocyte studies, there was a significant decrease in the erythrocyte glutathione with cyclophosphamide (50µM) (0.953 ± 0110mM) when co-incubated the rat microsomal system, compared to the control (1.124 ± 0.032mM). Differences were considered statistically significant for p<0.05, using the Student's two tailed 't' test with Bonferroni's correction. There was no significant depletion of glutathione with phenytoin, carbamazepine and sulphamethoxazole when co-incubated with the rat microsomalsystem, compared to the control.

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The aim of this research project is to evaluate whether or not pullulan films are suitable to buccal drug delivery of a phosphodiesterase5 (PDE5) inhibitor yonkenafil, which was discovered in our research group and currently is under phase II clinical trial for treatment of erectile dysfunction. Variable formulations of pullulan films were designed and the films were prepared. Mechanical properties of the films, in vitro drug release and polymer dissolution, in vitro drug penetration through porcine esophageal mucosa were investigated. The plasticization effects of solvents, polyols and acids to the films were studied by tensile test, and differential scanning calorimetry, thermogravimetric analysis, fourier transform-infrared, scanning electron microscopy, optical microscopy was applied to analyse the structure and chemical-bonding between pullulan and the additives within the films. Release mathematics models were used in the study of the mechanism of drug releases and polymer dissolutions. Ethanol, menthol, fatty acids, and sodium dodecyl sulphate were employed as penetration enhancers to pretreat the tissue. Various plasticizers and acids were applied into the films and the result showed polyethylene glycol 400 and 600 had the excellent plasticization effect on the drug-free pullulan films, while lactic acid was the best plasticizer for the drug-loaded films. Both PEG400 and lactic acid had a great effect on the drug release from the films in vitro, and all the results indicated that the hydroxyl and carboxyl groups of pullulan and the additives influenced the mechanical properties of the films significantly, and also altered drug release mechanisms. Ethanol shows the greatest enhancing ability on the drug permeation through the porcine esophageal mucosa. A possible mechanism for this is that ethanol interferes with the structure of the lipids in the mucosa, resulting in increased partitioning of the drug into the membrane.

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This research project is concerned with the design, synthesis and development of new phosphodiesterase 5 (PDE5) inhibitors with improved selectivities and lower toxicities. Two series of a 5 member and a 6 member ring fused heterocyclic compounds were designed, and synthesized. By alteration of starting materials and fragments, two virtual libraries, each is consisted of close to hundred compounds, were obtained successfully. The screening of sexual stimulation activity with rabbits demonstrated both groups of compounds were able to stimulate rabbit penile erection significantly. The following toxicity studies revealed 2-(substituted-sulfonylphenyl)-imidazo [1,5-a]-1,3,5-triazine-4-(3H)-one group possessed an unacceptable toxicity with oral LD50 about 200mg/kg; while 2-(substituted-sulfonylphenyl)-pyrrolo[2,3-d]pyrimidin-4-one group showed an acceptable toxicity with oral LD50 over 2000mg/kg. The continued bioactivity studies showed yonkenafil, the representative of 2-(substituted-sulfonylphenyl)-pyrrolo[2,3-d]pyrimidin-4-one group, has a better selectivity towards PDE5 and PDE6 than sildenafil and a better overall profile of sexual stimulation on animals than sildenafil. Chronic toxicity studies of yonkenafil further confirmed yonkenafil did not cause any serious side effect and damage on animal models and most actions were explainable. Based on evidences of the above studies, yonkenafil were recommended to enter clinical trials by the regulation authority of China, SFDA. Currently yonkenafil has been through the Phase I clinical trials and ready to progress into Phase II. Hopefully, yonkenafil will provide an alternative to the ED patients in the future.

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Membrane lipid composition is an important correlate of the rate of aging of animals. Dietary methionine restriction (MetR) increases lifespan in rodents. The underlying mechanisms have not been elucidated but could include changes in tissue lipidomes. In this work, we demonstrate that 80% MetR in mice induces marked changes in the brain, spinal cord, and liver lipidomes. Further, at least 50% of the lipids changed are common in the brain and spinal cord but not in the liver, suggesting a nervous system-specific lipidomic profile of MetR. The differentially expressed lipids includes (a) specific phospholipid species, which could reflect adaptive membrane responses, (b) sphingolipids, which could lead to changes in ceramide signaling pathways, and (c) the physiologically redox-relevant ubiquinone 9, indicating adaptations in phase II antioxidant response metabolism. In addition, specific oxidation products derived from cholesterol, phosphatidylcholine, and phosphatidylethanolamine were significantly decreased in the brain, spinal cord, and liver from MetR mice. These results demonstrate the importance of adaptive responses of membrane lipids leading to increased stress resistance as a major mechanistic contributor to the lowered rate of aging in MetR mice. © 2013 American Chemical Society.

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Bromocriptine is an ergot alkaloid dopamine D receptor agonist that has been used extensively in the past to treat hyperprolactinaemia, galactorrhoea and Parkinsonism. It is known that hypothalamic hypodopaminergic states and disturbed circadian rhythm are associated with the development of insulin resistance, obesity and diabetes in animals and humans. When administered in the early morning at the start of the light phase, a new quick release (QR) formulation of bromocriptine appears to act centrally to reset circadian rhythms of hypothalamic dopamine and serotonin and improve insulin resistance and other metabolic abnormalities. Phase II and III clinical studies show that QR-bromocriptine lowers glycated haemoglobin by 0.6-1.2% (7-13 mmol/mol) either as monotherapy or in combination with other antidiabetes medications. Apart from nausea, the drug is well tolerated. The doses used to treat diabetes (up to 4.8 mg daily) are much lower than those used to treat Parkinson's disease and have not been associated with retroperitoneal fibrosis or heart valve abnormalities. QR-bromocriptine (Cycloset™) has recently been approved in the USA for the treatment of type 2 diabetes mellitus (T2DM). Thus, a QR formulation of bromocriptine timed for peak delivery in the early morning may provide a novel neurally mediated approach to the control of hyperglycaemia in T2DM. © 2010 Blackwell Publishing Ltd.

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One of the aims of the Science and Technology Committee (STC) of the Group on Earth Observations (GEO) was to establish a GEO Label- a label to certify geospatial datasets and their quality. As proposed, the GEO Label will be used as a value indicator for geospatial data and datasets accessible through the Global Earth Observation System of Systems (GEOSS). It is suggested that the development of such a label will significantly improve user recognition of the quality of geospatial datasets and that its use will help promote trust in datasets that carry the established GEO Label. Furthermore, the GEO Label is seen as an incentive to data providers. At the moment GEOSS contains a large amount of data and is constantly growing. Taking this into account, a GEO Label could assist in searching by providing users with visual cues of dataset quality and possibly relevance; a GEO Label could effectively stand as a decision support mechanism for dataset selection. Currently our project - GeoViQua, - together with EGIDA and ID-03 is undertaking research to define and evaluate the concept of a GEO Label. The development and evaluation process will be carried out in three phases. In phase I we have conducted an online survey (GEO Label Questionnaire) to identify the initial user and producer views on a GEO Label or its potential role. In phase II we will conduct a further study presenting some GEO Label examples that will be based on Phase I. We will elicit feedback on these examples under controlled conditions. In phase III we will create physical prototypes which will be used in a human subject study. The most successful prototypes will then be put forward as potential GEO Label options. At the moment we are in phase I, where we developed an online questionnaire to collect the initial GEO Label requirements and to identify the role that a GEO Label should serve from the user and producer standpoint. The GEO Label Questionnaire consists of generic questions to identify whether users and producers believe a GEO Label is relevant to geospatial data; whether they want a single "one-for-all" label or separate labels that will serve a particular role; the function that would be most relevant for a GEO Label to carry; and the functionality that users and producers would like to see from common rating and review systems they use. To distribute the questionnaire, relevant user and expert groups were contacted at meetings or by email. At this stage we successfully collected over 80 valid responses from geospatial data users and producers. This communication will provide a comprehensive analysis of the survey results, indicating to what extent the users surveyed in Phase I value a GEO Label, and suggesting in what directions a GEO Label may develop. Potential GEO Label examples based on the results of the survey will be presented for use in Phase II.

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Dapsone (DDS) is currently used in the treatment of leprosy, malaria and in infections with Pneumocystis jirovecii and Toxoplasma gondii in AIDS patients. Adverse effects of DDS involve methemoglobinemia and hemolysis and, to a lower extent, liver damage, though the mechanism is poorly characterized. We evaluated the effect of DDS administration to male and female rats (30 mg/kg body wt, twice a day, for 4 days) on liver oxidative stress through assessment of biliary output and liver content of reduced (GSH) and oxidized (GSSG) glutathione, lipid peroxidation, and expression/activities of the main antioxidant enzymes glutathione peroxidase, superoxide dismutase, catalase and glutathione S-transferase. The influence of DDS treatment on express ion/activity of the main DDS phase-II- metabolizing system, UDP-glucuronosyltransferase (UGT), was additionally evaluated. The involvement of dapsone hydroxylamine (DDS-NHOH) generation in these processes was estimated by comparing the data in male and female rats since N-hydroxylation of DDS mainly occurs in males. Our studies revealed an increase in the GSSG/GSH biliary output ratio, a sensitive indicator of oxidative stress, and in lipid peroxiclation, in male but not in female rats treated with DDS. The activity of all antioxidant enzymes was significantly impaired by DDS treatment also in male rats, whereas UGT activity was not affected in any sex. Taken together, the evidence indicates that DDS induces oxidative stress in rat liver and that N-hydroxylation of DDS was the likely mediator. Impairment in the activity of enzymatic antioxidant systems, also associated with DDS-NHOH formation, constituted a key aggravating factor.

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Four aspects of horizontal genetic transfer during heterokaryon formation were examined in the asexual pathogen Fusarium oxysporum f.sp. cubense (Foc): (1) variability based on method of heterokaryon formation; (2) differences in nuclear and mitochondrial inheritance; (3) the occurrence of recombination without nuclear fusion; (4) the occurrence of horizontal genetic transfer between distantly related isolates. The use of non-pathogenic strains of Fusarium oxysporum as biocontrol agents warrants a closer examination at the reproductive life cycle of this fungus, particularly if drug resistance or pathogenicity genes can be transmitted horizontally. Experiments were divided into three phases. Phase I looked at heterokaryon formation by hyphal anastomosis and protoplast fusion. Phase II was a time course of heterokaryon formation to look at patterns of nuclear and mitochondrial inheritance. Phase III examined the genetic relatedness of the different vegetative compatibility groups using a multilocus analysis approach. Heterokaryon formation was evident within and between vegetative compatibility groups. Observation of non-parental genotypes after heterokaryon formation confirmed that, although a rare event, horizontal genetic transfer occurred during heterokaryon formation. Uniparental mitochondria inheritance was observed in heterokaryons formed either by hyphal anastomosis or protoplast fusion. Drug resistance was expressed during heterokaryon formation, even across greater genetic distances than those distances imposed by vegetative compatibility. Phylogenies inferred from different molecular markers were incongruent at a significant level, challenging the clonal origins of Foc. Mating type genes were identified in this asexual pathogen Polymorphisms were detected within a Vegetative Compatibility Group (VCG) suggesting non-clonal inheritance and/or sexual recombination in Foc. This research was funded in part by a NIH-NIGMS (National Institutes of Health-National Institute of General Medical Sciences) Grant through the MBRS (Minority Biomedical Research Support), the Department of Biological Sciences and the Tropical Biology Program at FIU. ^

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An integrated, dual-phase study design assessed the health and nutritional status and practices of African-American (A-A), Caribbean (A-C), and white non-Hispanic (W-A) women during perimenopause (40–55 years). During Phase I, four focus groups (n = 37) of male and female participants discussed the health and social implications of perimenopause. A conceptual framework for the main study (Phase II) was developed from the focus groups' findings, in concert with the main study's specific aims and objectives. ^ The main study, a cross-sectional survey, quantitatively assessed the health and nutritional status of a convenience sample of 109 women (25 A-A, 31 A-C and 53 W-A), who met specific eligibility criteria. Using seven instruments, sociodemographic, dietary, medical, reproductive health, health practice and anthropometric data were collected. ^ The groups were of comparable age, education, and socioeconomic status (SES). Despite these similarities, statistically significant interethnic nutritional status differences were found. Significantly more total energy and energy from fat were consumed by A-A than W-A and A-C women. Also, significantly more A-A and A-C than W-A women were overweight or obese with android-type weight patterning. ^ Overall, iron and calcium Recommended Dietary Allowances (RDA's) were not met by 35% and 68% of participants, respectively. Iron deficiency anemia was reported by 29% of participants while 33% reported heavier menstrual bleeding. Coupled with suboptimal iron intakes, this is likely to present a serious public health problem. Similarly, increased bone demineralization characteristic of perimenopause, coupled with suboptimal calcium intakes could precipitate another public health problem, osteoporosis. ^ Participants had different expectations about the role of medical care during perimenopause. Significantly more white (57%) than black (38% [A-A and AC]) women sought medical attention for symptoms. Whereas Hormone Replacement Therapy (HRT) was prescribed for 25% of them, only 13% were compliant at enrollment. ^ The trends and statistically significant findings of this study have huge public health policy implications. It is imperative that appropriate policies are formulated to ensure that America's ethnically diverse perimenopausal women have ready access to culturally appropriate care. This would optimize their health outcomes, and enhance their quality of life and productive capacities at this critical juncture of their lives. ^

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The purpose of this study was to develop a developmentally appropriate new nutrition education tool, the Rainbow Diet for Children (RDFC), to encourage and aid parents in feeding their children according to current national recommendations. In phase I of the study, the RDFC was developed. Foods were grouped based on color. ^ Phase II of the study consisted of actual testing of the RDFC with children. ^ A pre and post intervention comparison revealed three significant differences. For the FGP group cholesterol intake was significantly (p < 0.006) increased and thiamin intake was significantly (p < 0.022) decreased. For the control group there was a significant increase (p < 0.005) in the vitamin A intake. ^ For the inter group mean change scores (posttest-pretest) two significant differences were found. First, cholesterol intake in the RDFC was significantly (p < 0.045) decreased while for the other two groups it increased significantly. Furthermore, the mean monounsaturated fat intake for the RDFC group significantly decreased (p < 0.047) from pre to post, whereas in the other two groups it was increased. (Abstract shortened by UMI.) ^

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This study investigated the effects of self-monitoring on the homework completion and accuracy rates of four, fourth-grade students with disabilities in an inclusive general education classroom. A multiple baseline across subjects design was utilized to examine four dependent variables: completion of spelling homework, accuracy of spelling homework, completion of math homework, accuracy of math homework. Data were collected and analyzed during baseline, three phases of intervention, and maintenance. ^ Throughout baseline and all phases, participants followed typical classroom procedures, brought their homework to school each day and gave it to the general education teacher. During Phase I of the intervention, participants self-monitored with a daily sheet at home and on the computer at school in the morning using KidTools (Fitzgerald & Koury, 2003); a student friendly, self-monitoring program. They also participated in brief daily conferences to review their self-monitoring sheets with the investigator, their special education teacher. Phase II followed the same steps except conferencing was reduced to two days a week, which were randomly selected by the researcher and Phase III conferencing was one random day a week. Maintenance data were taken over a two-to-three week period subsequent to the end of the intervention. ^ Results of this study demonstrated self-monitoring substantially improved spelling and math homework completion and accuracy rates of students with disabilities in an inclusive, general education classroom. On average, completion and accuracy rates were highest over baseline in Phase III. Self-monitoring led to higher percentages of completion and accuracy during each phase of the intervention compared to baseline, group percentages also rose slightly during maintenance. Therefore, results suggest self-monitoring leads to short-term maintenance in spelling and math homework completion and accuracy. ^ This study adds to the existing literature by investigating the effects of self-monitoring of homework for students with disabilities included in general education classrooms. Future research should consider selecting participants with other demographic characteristics, using peers for conferencing instead of the teacher, and the use of self-monitoring with other academic subjects (e.g., science, history). Additionally, future research could investigate the effects of each of the two self-monitoring components used alone, with or without the conferencing.^

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This dissertation is a collection of three economics essays on different aspects of carbon emission trading markets. The first essay analyzes the dynamic optimal emission control strategies of two nations. With a potential to become the largest buyer under the Kyoto Protocol, the US is assumed to be a monopsony, whereas with a large number of tradable permits on hand Russia is assumed to be a monopoly. Optimal costs of emission control programs are estimated for both the countries under four different market scenarios: non-cooperative no trade, US monopsony, Russia monopoly, and cooperative trading. The US monopsony scenario is found to be the most Pareto cost efficient. The Pareto efficient outcome, however, would require the US to make side payments to Russia, which will even out the differences in the cost savings from cooperative behavior. The second essay analyzes the price dynamics of the Chicago Climate Exchange (CCX), a voluntary emissions trading market. By examining the volatility in market returns using AR-GARCH and Markov switching models, the study associates the market price fluctuations with two different political regimes of the US government. Further, the study also identifies a high volatility in the returns few months before the market collapse. Three possible regulatory and market-based forces are identified as probable causes of market volatility and its ultimate collapse. Organizers of other voluntary markets in the US and worldwide may closely watch for these regime switching forces in order to overcome emission market crashes. The third essay compares excess skewness and kurtosis in carbon prices between CCX and EU ETS (European Union Emission Trading Scheme) Phase I and II markets, by examining the tail behavior when market expectations exceed the threshold level. Dynamic extreme value theory is used to find out the mean price exceedence of the threshold levels and estimate the risk loss. The calculated risk measures suggest that CCX and EU ETS Phase I are extremely immature markets for a risk investor, whereas EU ETS Phase II is a more stable market that could develop as a mature carbon market in future years.

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A comprehensive method for the analysis of 11 target pharmaceuticals representing multiple therapeutic classes was developed for biological tissues (fish) and water. Water samples were extracted using solid phase extraction (SPE), while fish tissue homogenates were extracted using accelerated solvent extraction (ASE) followed by mixed-mode cation exchange SPE cleanup and analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS). Among the 11 target pharmaceuticals analyzed, trimethoprim, caffeine, sulfamethoxazole, diphenhydramine, diltiazem, carbamazepine, erythromycin and fluoxetine were consistently detected in reclaimed water. On the other hand, caffeine, diphenhydramine and carbamazepine were consistently detected in fish and surface water samples. In order to understand the uptake and depuration of pharmaceuticals as well as bioconcentration factors (BCFs) under the worst-case conditions, mosquito fish were exposed to reclaimed water under static-renewal for 7 days, followed by a 14-day depuration phase in clean water. Characterization of the exposure media revealed the presence of 26 pharmaceuticals while 5 pharmaceuticals including caffeine, diphenhydramine, diltiazem, carbamazepine, and ibuprofen were present in the organisms as early as 5 h from the start of the exposure. Liquid chromatography ultra-high resolution Orbitrap mass spectrometry was explored as a tool to identify and quantify phase II pharmaceutical metabolites in reclaimed water. The resulting data confirmed the presence of acetyl-sulfamethoxazole and sulfamethoxazole glucuronide in reclaimed water. To my knowledge, this is the first known report of sulfamethoxazole glucuronide surviving intact through wastewater treatment plants and occurring in environmental water samples. Finally, five bioaccumulative pharmaceuticals including caffeine, carbamazepine, diltiazem, diphenhydramine and ibuprofen detected in reclaimed water were investigated regarding the acute and chronic risks to aquatic organisms. The results indicated a low potential risk of carbamazepine even under the worst case exposure scenario. Given the dilution factors that affect environmental releases, the risk of exposure to carbamazepine will be even more reduced.

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This study investigated the effects of an explicit individualized phonemic awareness intervention administered by a speech-language pathologist to 4 prekindergarten children with phonological speech sound disorders. Research has demonstrated that children with moderate-severe expressive phonological disorders are at-risk for poor literacy development because they often concurrently exhibit weaknesses in the development of phonological awareness skills (Rvachew, Ohberg, Grawburg, & Heyding, 2003).^ The research design chosen for this study was a single subject multiple probe design across subjects. After stable baseline measures, the participants received explicit instruction in each of the three phases separately and sequentially. Dependent measures included same-day tests for Phase I (Phoneme Identity), Phase II (Phoneme Blending), and Phase III (Phoneme Segmentation), and generalization and maintenance tests for all three phases.^ All 4 participants made substantial progress in all three phases. These skills were maintained during weekly and biweekly maintenance measures. Generalization measures indicated that the participants demonstrated some increases in their mean total number of correct responses in Phase II and Phase III baseline while the participants were in Phase I intervention, and more substantial increases in Phase III baseline while the participants were in Phase II intervention. Increased generalization from Phases II to III could likely be explained due to the response similarities in those two skills (Cooper, Heron, & Heward, 2007).^ Based upon the findings of this study, speech-language pathologists should evaluate phonological awareness in the children in their caseloads prior to kindergarten entry, and should allocate time during speech therapy to enhance phonological awareness and letter knowledge to support the development of both skills concurrently. Also, classroom teachers should collaborate with speech-language pathologists to identify at-risk students in their classrooms and successfully implement evidence-based phonemic awareness instruction. Future research should repeat this study including larger groups of children, children with combined speech and language delays, children of different ages, and ESOL students.^