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1.
Pediatr Neonatol ; 65(1): 71-75, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37652825

RESUMO

BACKGROUND: Overuse of empirical intravenous antibiotics in neonates in high-income countries (HICs) is well documented. The Kaiser Permanente neonatal early-onset sepsis (EOS) calculator is an evidence-based sepsis risk assessment tool that has demonstrated potential to reduce antibiotic usage in this population. The incidence of early-onset sepsis in most HICs is 0.4-0.8 per 1000 live births. The objective was to evaluate the calculator's impact on antibiotic rates and length of stay in a regional level II Special Care Nursery. METHODS: A single-centre retrospective cohort study compared antibiotic administration rates in the first 72 h in neonates ≥35 weeks gestation born during two 6-month periods in 2019 (pre-EOS calculator) and 2021 (post-EOS calculator). Electronic and paper case records were accessed to capture data. Continuous data were summarised using mean and standard deviation, and categorical data were summarized using frequency distributions. There were 951 (2019) and 1129 (2021) infants born during the study periods. RESULTS: Following implementation of the calculator, antibiotic exposure decreased from 13.7% to 4.7% of all neonates without reported negative outcomes. Mean length of stay for neonates born across the two periods decreased from 2.38 to 2.13 days. Indications for antibiotic use shifted more towards clinical condition and away from obstetric risk factors. There were no culture-proven cases of sepsis or readmissions with EOS in either period. CONCLUSION: Implementation of the EOS calculator significantly reduced exposure to antibiotics, without adverse outcomes.


Assuntos
Sepse Neonatal , Sepse , Recém-Nascido , Lactente , Gravidez , Feminino , Humanos , Antibacterianos/uso terapêutico , Sepse Neonatal/tratamento farmacológico , Sepse Neonatal/epidemiologia , Austrália Ocidental , Estudos Retrospectivos , Medição de Risco , Sepse/tratamento farmacológico , Sepse/epidemiologia
3.
Tob Prev Cessat ; 9: 30, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37789930

RESUMO

INTRODUCTION: The use of e-cigarettes has grown in popularity worldwide. From their manufacturing, use, and disposal, the environmental impacts of e-cigarettes present a novel public health concern that needs to be urgently investigated. However, very limited studies have focused on the subject matter. The present study aims to review available studies to identify the environmental impacts of e-cigarettes. METHODS: In this scoping review, we undertook a search in two databases (PubMed and Web of Science) from inception until 21 March 2023, and a gray literature search in Google Scholar. Reference lists of publications included in the scoping review were screened manually for additional relevant publications. Scientific publications that were in English and focused on the potential impacts of e-cigarettes on the environment were included. RESULTS: A total of 693 publications were identified, of which 33 were subjected to full-text review and 9 publications were finally included in the review. The impacts on air quality, water, land use, and animals, water and energy consumption, with associated environmental impacts, increased pollution and emissions due to greater e-cigarette production, having harmful and toxic components, creating pollution and waste issues, and global environmental impacts due to manufacturing and importing ingredients and components from low- and middle-income countries, were identified as the environmental impacts of e-cigarettes. CONCLUSIONS: Despite the emphasis on the environmental threat of e-cigarettes, there are limited scientific studies on the environmental impacts of the e-cigarette life cycle. Considering the rapid expansion of e-cigarette usage, there is an urgent need for a rigorous assessment of their life-cycle environmental burden of the various potential health, environmental, and other consequences.

4.
Epidemiologia (Basel) ; 2(4): 519-539, 2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-36417214

RESUMO

In late 2020 and early 2021, with the eagerly anticipated regulatory approval of vaccines against SARS-CoV-2, the urgent global effort to inoculate populations against this devastating virus was underway. These case studies examine the early stages of COVID-19 vaccine rollouts across nine regions from around the world (Brazil, India, Indonesia, Ireland, Israel, Nigeria, Taiwan, United Kingdom and United States). By evaluating and comparing different approaches used to immunize against a novel pathogen, it is possible to learn a great deal about which methods were successful, and in which areas strategies can be improved. This information is applicable to the ongoing global vaccination against this virus, as well as in the event of future pandemics. Research was conducted by following and tracking the progress of vaccine rollouts in the nine regions, using published clinical trials, government documents and news reports as sources of data. Results relate to the proportion of populations that had received at least one COVID-19 dose by 28 February 2021. Outcomes are discussed in the context of three key pillars integral to all immunization programs: procurement of vaccines, communication with the public and distribution of doses to individuals.

5.
Pathobiology ; 86(2-3): 77-82, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30347405

RESUMO

BACKGROUND: The American Joint Commission Cancer (AJCC) Cancer Staging Manual 8th edition introduced a breast cancer (BC) Prognostic Stage (PS) that combines tumour grade, oestrogen (ER), progesterone (PgR), and human epidermal growth factor-2 (HER2) receptor status with Anatomic TNM Stage (AS). In a further modification, patients with early BC and an Oncotype DX® Recurrence Score (RS) < 11 are assigned to PS 1A irrespective of grade and size up to 5 cm. This study profiles the impact of these changes on staging in patients with early BC and RS < 11. METHODS: A total of 127 patients, with primary BC and RS < 11, were identified from a consecutive series of 729 patients with ER-positive, HER2-negative, lymph node-negative, primary BC whose tumours were tested using the Oncotype DX® 21 multigene assay. Each patient was assigned AS, PS, and RS-modified PS, and staging categories were compared. RESULTS: Applying AS, 100 patients were stage IA and 27 IIA. Applying PS, 89 were stage IA, 33 IB, 4 IIA, and 1 IIB. All patients were IA according to RS-modified PS. Comparing PS to AS, 26.7% of patients (n = 34) changed stage, 9.4% (n = 12) to a higher and 17.3% (n = 22) to a lower stage. RS-modified PS versus AS resulted in downstaging in 21.3% (n = 27). Comparing PS modified by RS to PS alone, 29.9% (n = 38) were downstaged. CONCLUSION: Application of PS and RS-modified PS results in tumour downstaging in approximately 20% of patients with early BC. Upstaging was observed in 9% of patients when staged according to PS and was primarily due to the impact of high histological grade.


Assuntos
Neoplasias da Mama/diagnóstico , Recidiva Local de Neoplasia , Estadiamento de Neoplasias/métodos , Adulto , Idoso , Biomarcadores Tumorais/genética , Neoplasias da Mama/patologia , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Gradação de Tumores , Receptor ErbB-2/genética , Receptores de Estrogênio/genética , Estados Unidos
6.
Transl Androl Urol ; 7(Suppl 3): S264-S270, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30159231

RESUMO

BACKGROUND: To assess postpartum use of secondary contraception with vasectomy within Pregnancy Risk Assessment Monitoring System (PRAMS). METHODS: Secondary contraception and type of method used were assessed among married women reporting partner vasectomy 4 months after a recent live birth in female residents of 15 US states and New York City who participated in the 2007-2011 PRAMS. RESULTS: Between 2007 and 2011, 1,004 married women who had a recent live birth participating in PRAMS reported they and their partners relied on vasectomy for postpartum contraception. Among these couples, 57.8% reported not using additional forms of contraception postpartum. Of those reporting additional contraception, condoms were most commonly used (50.0%), followed by oral contraceptive pills (26.5%), and withdrawal (9.5%). Multivariable modeling showed that use of secondary contraception was twice as high among women reporting a second birth versus women reporting a fourth or higher birth [adjusted prevalence odds ratio (POR) =2.0 (1.1-3.2)]. No other sociodemographic characteristics (maternal age, maternal race, parental education, household income) were significantly associated with use of secondary contraception with vasectomy. CONCLUSIONS: Most couples within PRAMS reporting partner vasectomy as postpartum contraception did not use secondary contraception in the months immediately after vasectomy, and, of those who did, most relied on less effective methods. Clinicians need to better understand reasons for limited use of secondary contraception with vasectomy to improve counseling strategies for reducing unintended pregnancy.

7.
Urol Clin North Am ; 43(2): 217-22, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27132579

RESUMO

Testosterone and sexual function are related. Current evidence suggests that testosterone replacement therapy (TRT) may improve sexual dysfunction. Sexual dysfunction in men who are hypogonadal, mixed, or eugonadal have all been examined through numerous studies. The most recent large analysis showed an overall improvement in sexual function outcomes in men treated with TRT. This improvement is difficult to measure and seems to differ based on the baseline hormonal status of the patient at the beginning of treatment.


Assuntos
Disfunções Sexuais Fisiológicas/fisiopatologia , Testosterona/fisiologia , Disfunção Erétil/tratamento farmacológico , Disfunção Erétil/fisiopatologia , Humanos , Libido/efeitos dos fármacos , Masculino , Testosterona/uso terapêutico
8.
Res Rep Urol ; 8: 61-70, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27200305

RESUMO

INTRODUCTION: Peyronie's disease (PD) has significant effect on patients and their partners. We provide a current review of the epidemiology as well as the nonsurgical and surgical treatment of PD. MATERIALS AND METHODS: Review of literature pertaining to PD with focus on epidemiology and treatment options. CONCLUSION: PD is common and likely underreported. The availability of new and highly effective treatment options will catalyze patient awareness and subsequently the prevalence of disease.

9.
J Urol ; 191(1): 159-63, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24050893

RESUMO

PURPOSE: Prostate cancer treatment results in several sexually related side effects beyond the well studied erectile dysfunction. Climacturia (leakage of urine during orgasm) has been reported after prostatectomy but studies have been limited by multiple factors. In this study we examine the prevalence, causes and impact on orgasm function of climacturia after definitive treatment of prostate cancer with surgery or radiation. MATERIALS AND METHODS: A total of 906 anonymous surveys were sent to patients with prostate cancer treated with surgery and/or radiation. Respondents were asked about the presence of urinary leakage, climacturia and various elements related to sexual and orgasmic function. We estimated the prevalence of climacturia, evaluated the differences between those with and without climacturia, and assessed the impact of climacturia on orgasmic function. RESULTS: Overall 412 surveys were returned and available for analysis, and of these respondents 75.2% were sexually active or experiencing orgasms. Climacturia was reported by 22.6% of these respondents, and by 28.3%, 5.2% and 28.6% of those treated with surgery, radiation, or both, respectively (p <0.001). The use of aides to obtain an erection (OR 2.24, 95% CI 1.08-4.93, p = 0.035) and the presence of urinary incontinence (OR 3.09, 95% CI 1.66-5.88, p <0.001) were also associated with climacturia in a multivariate logistic regression model. Climacturia had no significant impact on orgasmic function and satisfaction. CONCLUSIONS: Climacturia is experienced by a substantial proportion of men after undergoing definitive treatment of prostate cancer. We found a complex relationship between stress urinary incontinence and climacturia, and noted that the presence of climacturia does not necessarily negatively impact sexual satisfaction.


Assuntos
Neoplasias da Próstata/terapia , Disfunções Sexuais Fisiológicas/etiologia , Incontinência Urinária/etiologia , Idoso , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Orgasmo , Prostatectomia/efeitos adversos , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia , Radioterapia/efeitos adversos
10.
Adv Exp Med Biol ; 791: 53-66, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23955672

RESUMO

Recent advances, including the human genome project and numerous studies of cancer and other diseases, have shown that the genetic code is not simply limited to the sequence of the four bases of DNA but also includes epigenetic programming, heritable changes that affect gene expression [Riggs A, Martinssen R, Russo V (2007) Introduction. In: Riggs A, Martinssen R, Russo V (eds) Epigenetics mechanisms of gene regulation. Cold Spring Harbor Press, New York]. The science of epigenetics is important in understanding many diseases and biological processes, including in identifying the causes of disease and better understanding the mechanisms by which the environment can affect gene expression [Carrell Fertil Steril 97 (2):267-274, 2012]. This chapter will focus on the epigenome of sperm and particularly highlight the potential role of the sperm epigenome in embryogenesis.The sperm epigenome is unique and highly specialized because of the unique nature and function of sperm and because of the diverse requirements for successful fertilization. Due to the need for motility, sperm chromatin must be compacted and highly organized. During spermiogenesis the chromatin is packaged tightly into the sperm head by the replacement of most histones with protamines. This allows for protection of the DNA from the hostile environment in the female reproductive tract. Remaining histones can have chemical modifications to the tails of the protein that either facilitate or repress gene transcription. Sperm, like embryonic stem cells, have a unique pattern of histone modifications that includes both activating and silencing marks in the promoters of genes associated with development. These bivalent marks, along with DNA hypomethylation, comprise a unique state in which the key genes are "poised" for possible activation in embryogenesis. Sperm epigenetic abnormalities have been linked with multiple diseases including male factor infertility and poor embryogenesis.


Assuntos
Desenvolvimento Embrionário/genética , Epigênese Genética/fisiologia , Genoma/fisiologia , Infertilidade Masculina/genética , Espermatozoides/metabolismo , Animais , Feminino , Histonas/fisiologia , Humanos , Infertilidade Masculina/metabolismo , Masculino , Gravidez , Protaminas/metabolismo
11.
Ann R Coll Surg Engl ; 91(2): W18-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19317930

RESUMO

This case report details an unusual, but preventable, error in surgical site marking.


Assuntos
Tendão do Calcâneo/lesões , Erros Médicos/prevenção & controle , Adulto , Feminino , Humanos , Cuidados Pré-Operatórios , Ruptura
12.
Chemosphere ; 75(8): 1089-96, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19217141

RESUMO

The biodegradation pathways and metabolite yields of [3-(14)C] 8-2 fluorotelomer alcohol [8-2 FTOH, F(CF(2))(7)(14)CF(2)CH(2)CH(2)OH) in aerobic soils were investigated. Studies were conducted under closed (static) and continuous headspace air flow to assess differences in degradation rate and metabolite concentrations in soil and headspace. Aerobic degradation pathways in soils were in general similar to those in aerobic sludge and bacterial culture. (14)C mass balance was achieved in soils incubated for up to 7 months. Up to 35% (14)C dosed was irreversibly bound to soils and was only recoverable by soil combustion. The average PFOA yield was approximately 25%. Perfluorohexanoic acid (PFHxA) yield reached approximately 4%. (14)CO(2) yield was 6.8% under continuous air flow for 33 days. Three metabolites not previously identified in environmental samples were detected: 3-OH-7-3 acid [F(CF(2))(7)CHOHCH(2)COOH], 7-2 FT ketone [F(CF(2))(7)COCH(3)] and 2H-PFOA [F(CF(2))(6)CFHCOOH]. No perfluorononanoic acid (PFNA) was observed. The formation of 2H-PFOA, PFHxA, and (14)CO(2) shows that multiple -CF(2)- groups were removed from 8-2 FTOH. 7-3 Acid [F(CF(2))(7)CH(2)CH(2)COOH] reached a yield of 11% at day 7 and did not change thereafter. 7-3 Acid was incubated in aerobic soil and did not degrade to PFOA. 7-2 sFTOH [F(CF(2))(7)CH(OH)CH(3)], a transient metabolite, was incubated and degraded principally to PFOA. 7-3 Acid may be a unique metabolite from 8-2 FTOH biodegradation. The terminal ratio of PFOA to 7-3 acid ranged between 1.8-2.5 in soils and 0.6-3.2 in activated sludge, sediment, and mixed bacterial culture. This ratio may be useful in evaluating environmental samples to distinguish the potential contribution of 8-2 FTOH biodegradation to PFOA observed versus PFOA originating from other sources.


Assuntos
Hidrocarbonetos Fluorados/metabolismo , Poluentes do Solo/metabolismo , Solo , Biodegradação Ambiental , Cromatografia Líquida de Alta Pressão , Fluorocarbonos , Hidrocarbonetos Fluorados/análise , Cinética , Microbiologia do Solo , Poluentes do Solo/análise , Espectrometria de Massas em Tandem , Fatores de Tempo
13.
J Neurosurg ; 108(1): 3-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18173304

RESUMO

OBJECTIVES: Rathke cleft cysts (RCCs) are infrequently symptomatic, and apoplexy is one of the most unusual presentations. Only a few cases of apoplexy associated with RCCs have been reported, and their clinical, imaging, surgical, and pathological features are poorly understood. In the cases that have been reported, intracystic hemorrhage has been a consistent finding. The authors report 6 cases of RCCs in which the presenting clinical and imaging features indicated pituitary apoplexy, both with and without intracystic hemorrhage. METHODS: The authors retrospectively reviewed charts and magnetic resonance (MR) imaging studies obtained in patients who underwent transsphenoidal surgery for RCC. Six patients were identified who presented with symptoms and MR imaging characteristics consistent with pituitary apoplexy but were found intraoperatively to have an RCC. All 6 patients presented with a sudden headache, 2 with visual loss, and 1 with diplopia. Review of the preoperative MR images demonstrated mixed signal intensities in the sellar masses suggestive of a hemorrhagic pituitary tumor. In all patients there was a presumed clinical diagnosis of pituitary tumor apoplexy and an imaging-documented diagnosis of hemorrhagic pituitary tumor. RESULTS: All 6 patients underwent transsphenoidal resection to treat the suspected pituitary apoplexy. Intraoperative and histopathological findings were consistent with the diagnosis of an RCC in all cases. Only 2 cases showed evidence of hemorrhage intraoperatively. In all cases, an intracystic nodule was found within the RCC at surgery, and this intracystic nodule was present on the initial MR imaging when retrospectively reviewed. The imaging characteristics of the intracystic nodules were similar to those of acute hemorrhage seen in cases of pituitary apoplexy. CONCLUSIONS: The clinical and imaging features of RCCs appear similar to those of hemorrhagic pituitary tumors, making them often indistinguishable from pituitary apoplexy.


Assuntos
Cistos do Sistema Nervoso Central/diagnóstico , Hemorragias Intracranianas/diagnóstico , Apoplexia Hipofisária/diagnóstico , Adulto , Cistos do Sistema Nervoso Central/complicações , Cistos do Sistema Nervoso Central/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Hemorragias Intracranianas/etiologia , Hemorragias Intracranianas/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Apoplexia Hipofisária/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
14.
Environ Sci Technol ; 39(19): 7516-28, 2005 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16245823

RESUMO

There is increasing scientific interest to understand the environmental fate of fluorotelomer alcohols (FTOHs) and fluorotelomer-based products which may break down to FTOHs. Both are expected to enter aqueous waste streams, which would be processed in a wastewater treatment plant and therein subject to microbial biodegradation. We investigated the biodegradation of 3-14C, 1H,1H,2H,2H-perfluorodecanol [CF3(CF2)6(14)CF2CH2CH2OH, 14C-8-2 FTOH] in mixed bacterial culture and activated sludge. 14CO2 and 14C-organic volatiles in the headspace of the sealed bottles and bottles with continuous air flow were analyzed up to 4 months. After sample extraction with acetonitrile, 14C-labeled biotransformation products (metabolites) were quantified by LC/ARC (on-line liquid chromatography/ accurate radioisotope counting) and identified by quadrupole time-of-flight (Q-TOF) mass spectrometry and GC/MSD (mass selective detector). Three metabolites not yet reported in the literature have been identified as CF3(CF2)6(14)CHOHCH3 (7-2 sFTOH), CF3(CF2)6(14)CH=CHCOOH (7-3 unsaturated acid or 7-3 u acid), and CF3(CF2)6(14)CH=CHCONH2 (7-3 u amide) along with five previously reported metabolites [CF3(CF2)6(14)CF2CH2CHO (8-2 FTAL), CF3(CF2)6 (14)CF2CH2COOH (8-2 acid), CF3(CF2)6(14)CF=CHCOOH (8-2 u acid), CF3(CF2)6(14)CH2CH2COOH (7-3 acid), and CF3(CF2)6(14)COOH (PFOA)]. No CF3(CF2)6(14)CF2COOH (14C-PFNA) was observed, indicating that alpha-oxidation does not take place. It was found that strong adsorption to the activated sludge and subsequent transformation, even under continuous air flow, greatly reduced partitioning of 8-2 FTOH or any transformation products to air. CF3(CF2)4COOH (PFHA; perfluorohexanoic acid) was observed and increased in mixed bacterial culture over 28 days and accounted for about 1% of the initial 14C-8-2 FTOH concentration from day 28 to day 90. 14CO2 accounted for 1% of initial 14C in activated sludge with continuous air flow at day 1 and increased over time. In closed bottles, 14CO2 in the headspace of activated sludge medium increased to 12% of the available 14C over 135 days with periodic addition of ethanol, as compared to 3% when no additional ethanol was added. These results show that replenishment of organic carbon enhanced microbial mineralization of multiple--CF2--groups in the fluorocarbon chain of 14C-8-2 FTOH. At day 90 the net increase of fluoride ion in the mixed bacterial culture was 93 microg L(-1), equivalent to 12% of total mineralization (destruction) of the 14C-8-2 FTOH. These results demonstrate that perfluorinated carbon bonds of 14C-8-2 FTOH are defluorinated and mineralized by microorganisms under conditions which may occur in a wastewater treatment plant, forming shorter fluorinated carbon metabolites.


Assuntos
Álcoois/metabolismo , Bactérias/metabolismo , Fluorocarbonos/metabolismo , Esgotos/análise , Adsorção , Biodegradação Ambiental , Dióxido de Carbono/análise , Radioisótopos de Carbono/metabolismo , Cromatografia Líquida , Cinética , Espectrometria de Massas , Esgotos/microbiologia
15.
Environ Sci Technol ; 39(2): 531-8, 2005 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-15707053

RESUMO

This study investigated the biodegradation potential of 3-(14)C,1H,1H,2H,2H-perfluorodecanol [CF3(CF2)6(14)CF2CH2CH2OH, 14C-labeled 8-2 telomer B alcohol or 14C-labeled 8-2 TBA] by diluted activated sludge from a domestic wastewater treatment plant under aerobic conditions. After sample extraction with acetonitrile, biotransformation products were separated and quantified by LC/ARC (on-line liquid chromatography/accurate radioisotope counting) with a limit of quantification about 0.5% of the 14C counts applied to the test systems. Identification of biotransformation products was performed by quadrupole time-of-flight mass spectrometry. Three transformation products have been identified: CF3(CF2)6(14)CF2CH2COOH (8-2 saturated acid); CF3(CF2)6(14)CF=CHCOOH (8-2 unsaturated acid); and CF3(CF2)6(14)COOH (perfluorooctanoic acid, PFOA), representing 27, 6.0, and 2.1% of the initial 14C mass (14C counts applied) after 28 days, respectively. A transformation product, not yet reported in the literature, has also been observed and tentatively identified as CF3(CF2)6(14)CH2CH2COOH (2H,2H,3H,3H-perfluorodecanoic acid); it accounted for 2.3% of the mass balance after 28 days. The 2H,2H,3H,3H-perfluorodecanoic acid is likely a substrate for beta-oxidation, which represents one of the possible pathways for 8-2 telomer B alcohol degradation. The 8-2 saturated acid and 8-2 unsaturated acid cannot be directly used as substrates for beta-oxidation due to the proton deficiency in their beta-carbon (C3 carbon) and their further catabolism may be catalyzed by some other still unknown mechanisms. The 2H,2H,3H,3H-perfluorodecanoic acid may originate either from the major transformation product CF3(CF2)6(14)CF2CH2COOH or from other unidentified transformation products via multiple steps. Approximately 57% of the starting material remained unchanged after 28 days, likely due to its strong adsorption to the PTFE (poly(tetrafluoroethylene)) septa of the test vessels. No CF3(CF2)6(14)CF2COOH (perfluorononanoic acid) was observed, indicating that alpha-oxidation of CF3(CF2)6(14)CF2CH2COOH did not occur under the study conditions. Several 14C-labeled transformation products that have not yet been identified (each less than 1% of the mass balance) were also observed and together accounted for 7% of the total 14C mass balance after 28 days. It is not clear whether these unidentified transformation products were resulting from further metabolism of 8-2 saturated acid or 8-2 unsaturated acid. The results suggest that perfluorinated acid metabolites such as perfluorooctanoic acid account for only a very small portion of the transformation products observed. Also, the observed volatility and bioavailability of 14C-labeled 8-2 TBA for microbial degradation was markedly decreased as a result of the presence of a strongly adsorbing matrix such as PTFE in the experimental systems. It is apparent that the biological fate of 8-2 telomer B alcohol is determined by multiple degradation pathways, with neither beta-oxidation nor any other enzyme-catalyzed reactions as a single dominant (principal) mechanism under the study conditions.


Assuntos
Bactérias Aeróbias , Fluorocarbonos/metabolismo , Esgotos/química , Adsorção , Biotransformação , Radioisótopos de Carbono/análise , Catálise , Oxirredução , Eliminação de Resíduos Líquidos
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