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1.
J Pediatr ; 252: 198-203.e2, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36029823

RESUMEN

Sleep patterns of 419 toddlers with congenital heart disease were comparable with the normative population except for increased likelihood across the cohort of sleeping in parents' room and increased disrupted sleep in children aged 18-23 months. Disrupted sleep patterns were associated with lower maternal education and increased medical complexity.


Asunto(s)
Cardiopatías Congénitas , Trastornos del Sueño-Vigilia , Humanos , Lactante , Preescolar , Sueño , Padres , Trastornos del Sueño-Vigilia/epidemiología , Cardiopatías Congénitas/complicaciones , Cardiopatías Congénitas/epidemiología
2.
Health Expect ; 25(1): 91-102, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34472690

RESUMEN

OBJECTIVES: This study aimed to explore the experience of cognitive behavioural therapy (CBT) aimed at better management of chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME), rather than increasing activity. DESIGN: This was a qualitative study using grounded theory analysis. METHODS: Semi-structured interviews were conducted with 13 adults who had engaged in CBT at a specialist CFS/ME service in which CBT is aimed at improved management of the condition. RESULTS: A model was produced in which participants felt more able to cope with CFS/ME. Reduced fatigue did not seem to be a necessary precondition to managing. This has implications for CBT for CFS/ME. CONCLUSIONS: Specialist CBT for CFS/ME may result in improved coping and reduced distress, independently of changes in fatigue. PATIENT OR PUBLIC CONTRIBUTION: The researcher met with a representative from the university's service user advisory group (SAGE), who had lived experience of CFS/ME. They commented on possible questions for the interview topic guide and provided advice on ways in which ethical issues specific to CFS/ME could be considered, for example, prevention of harm during interviews. Second, for quality assurance as part of respondent validation, a proposed draft of the grounded theory was discussed with participants.


Asunto(s)
Terapia Cognitivo-Conductual , Síndrome de Fatiga Crónica , Adaptación Psicológica , Adulto , Síndrome de Fatiga Crónica/psicología , Síndrome de Fatiga Crónica/terapia , Humanos , Investigación Cualitativa , Especialización
3.
Bull Entomol Res ; 112(5): 626-635, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35229709

RESUMEN

Myzus persicae (Sulzer) is an important agricultural pest worldwide causing major economic losses due to its ability to transmit over 100 viruses including Potato virus Y (PVY). Myzus persicae shows considerable variation with respect to performance on its host plants. The objective of this study was to use a survival experiment, behavioural observations, including observations of probing and feeding behaviour obtained using the electrical penetration graph (EPG) technique, and a PVY acquisition experiment to determine whether or not potato was still the more suitable host for M. persicae originating on potato and reared on a novel host, table beet, for over 15 years. In a survival experiment, the pre-reproductive period was significantly longer while adult survival and whole longevity were significantly lower for M. persicae reared on beet fed beet leaves compared to M. persicae reared on potato fed potato leaves. The number of progenies produced and fecundity were both significantly reduced (90 and 85%, respectively) for M. persicae reared on beet fed beet leaves. Ethological observations and EPG assessment of M. persicae behaviour reared on beet placed on beet leaves showed significantly impaired behavioural responses compared to M. persicae reared on potato placed on potato leaves. The rate of PVY acquisition was the same for M. persicae reared on beet and on potato. These results indicate that after 15 years on table beet, M. persicae still performs better on its original host, potato, and appears to be a specialized potato-adapted genotype.


Asunto(s)
Áfidos , Potyvirus , Solanum tuberosum , Animales , Áfidos/fisiología , Potyvirus/fisiología , Conducta Alimentaria , Hojas de la Planta
4.
J Appl Clin Med Phys ; 22(9): 171-182, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34288376

RESUMEN

PURPOSE: Island blocking occurs in single-isocenter multiple-target (SIMT) stereotactic radiotherapy (SRS) whenever targets share multi-leaf collimator (MLC) leaf pairs. This study investigated the effect on plan quality and delivery, of reducing island blocking through collimator angle optimization (CAO). In addition, the effect of jaw tracking in this context was also investigated. METHODS: For CAO, an algorithm was created that selects the collimator angle resulting in the lowest level of island blocking, for each beam in any given plan. Then, four volume-modulated arc therapy (VMAT) SIMT SRS plans each were generated for 10 retrospective patients: two CAO plans, with and without jaw tracking, and two plans with manually selected collimator angles, with and without jaw tracking. Plans were then assessed and compared using typical quality assurance procedures. RESULTS: There were no substantial differences between plans with and without CAO. Jaw tracking produced statistically significant reduction in low-dose level parameters; healthy brain V10% and mean dose were reduced by 9.66% and 15.58%, respectively. However, quantitative values (108 cc for V10% and 0.35 Gy for mean dose) were relatively small in relation to clinical relevance. Though there were no statistically significant changes in plan deliverability, there was a notable trend of plans with jaw tracking having lower gamma analysis pass rates. CONCLUSION: These findings suggest that CAO has limited benefit in VMAT SIMT SRS of 2-6 targets when using a low-dose penalty to the healthy brain during plan optimization in Eclipse. As clinical benefits of jaw tracking were found to be minimal and plan deliverability was potentially reduced, a cautious approach would be to exclude jaw tracking in SIMT SRS plans.


Asunto(s)
Radiocirugia , Radioterapia de Intensidad Modulada , Humanos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Estudios Retrospectivos
5.
Nat Mater ; 18(7): 725-731, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31160800

RESUMEN

Self-organizing patterns with micrometre-scale features are promising for the large-area fabrication of photonic devices and scattering layers in optoelectronics. Pattern formation would ideally occur in the active semiconductor to avoid the need for further processing steps. Here, we report an approach to form periodic patterns in single layers of organic semiconductors by a simple annealing process. When heated, a crystallization front propagates across the film, producing a sinusoidal surface structure with wavelengths comparable to that of near-infrared light. These surface features initially form in the amorphous region within a micrometre of the crystal growth front, probably due to competition between crystal growth and surface mass transport. The pattern wavelength can be tuned from 800 nm to 2,400 nm by varying the film thickness and annealing temperature, and millimetre-scale domain sizes are obtained. This phenomenon could be exploited for the self-assembly of microstructured organic optoelectronic devices.

6.
Ecol Lett ; 22(12): 2028-2038, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31515929

RESUMEN

The relative influence of niche vs. neutral processes in ecosystem dynamics is an on-going debate, but the extent to which they structured the earliest animal communities is unknown. Some of the oldest known metazoan-dominated paleocommunities occur in Ediacaran age (~ 565 million years old) strata in Newfoundland, Canada and Charnwood Forest, UK. These comprise large and diverse populations of sessile organisms that are amenable to spatial point process analyses, enabling inference of the most likely underlying niche or neutral processes governing community structure. We mapped seven Ediacaran paleocommunities using LiDAR, photogrammetry and a laser line probe. We found that neutral processes dominate these paleocommunities, with niche processes exerting limited influence, in contrast with the niche-dominated dynamics of modern marine ecosystems. The dominance of neutral processes suggests that early metazoan diversification may not have been driven by systematic adaptations to the local environment, but instead may have resulted from stochastic demographic differences.


Asunto(s)
Ecosistema , Bosques , Animales , Canadá
7.
J Med Syst ; 43(6): 155, 2019 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-31025119

RESUMEN

The 30-day surgical mortality metric is endorsed by the National Quality Forum for value-based purchasing purposes. However, its integrity has been questioned, as there is documented evidence of hospital manipulation of this measure, by way of inappropriate palliative care designation and changes in patient selection. To determine if there is evidence of potential manipulation, we retrospectively analyzed 1,725,291 surgical admissions from 158 United States hospitals participating in the National Inpatient Sample from 2010 to 2011. As a way of evaluating unnecessary life-prolonging measures, we determined that a significant increase in mortality rate after post-operative day 30 (day 31-35) would indicate manipulation. We compared the post-operative mortality rates for each hospital between Post-Operative Day 26-30 and Post-Operative Day 31-35 using Wilcoxon signed-rank tests. After application of the Bonferroni correction, the results showed that none of the hospitals had a statistically significant increase in mortality after post-operative day 30. This analysis fails to impugn the integrity of this measure, as we did not identify any evidence of potential manipulation of the 30-day surgical mortality metric.


Asunto(s)
Calidad de la Atención de Salud/estadística & datos numéricos , Procedimientos Quirúrgicos Operativos/mortalidad , Femenino , Humanos , Estimación de Kaplan-Meier , Cuidados para Prolongación de la Vida/estadística & datos numéricos , Masculino , Propiedad , Características de la Residencia , Medición de Riesgo , Factores de Tiempo , Estados Unidos/epidemiología
8.
Am J Perinatol ; 35(12): 1197-1205, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29702712

RESUMEN

OBJECTIVE: Many critically ill neonates have an existing brain injury or are at risk of neurologic injury. We developed a "NeuroNICU" (neurologic neonatal intensive care unit) to better provide neurologically focused intensive care. STUDY DESIGN: Demographic and clinical variables, services delivered, and patient outcomes were recorded in a prospective database for all neonates admitted to the NeuroNICU between April 23, 2013, and June 25, 2015. RESULTS: In total, 546 neonates were admitted to the NeuroNICU representing 32% of all NICU admissions. The most common admission diagnoses were congenital heart disease (30%), extreme prematurity (18%), seizures (10%), and hypoxic-ischemic encephalopathy (9%). Neuromonitoring was common, with near-infrared spectroscopy used in 69%, amplitude-integrated electroencephalography (EEG) in 45%, and continuous video EEG in 35%. Overall, 43% received neurology or neurosurgery consultation. Death prior to hospital discharge occurred in 11%. Among survivors, 87% were referred for developmental follow-up, and among those with a primary neurologic diagnosis 57% were referred for neurology or neurosurgical follow-up. CONCLUSION: The NeuroNICU-admitted newborns with or at risk of brain injury comprise a high percentage of NICU volume; 38% had primary neurologic diagnoses, whereas 62% had medical diagnoses. We found many opportunities to provide brain focused intensive care, impacting a substantial proportion of newborns in our NICU.


Asunto(s)
Encefalopatías/diagnóstico , Enfermedades del Recién Nacido/diagnóstico , Unidades de Cuidado Intensivo Neonatal/organización & administración , Admisión del Paciente/estadística & datos numéricos , Desarrollo de Programa , California/epidemiología , Electroencefalografía , Femenino , Humanos , Hipoxia-Isquemia Encefálica/diagnóstico , Recién Nacido , Masculino , Neuroimagen , Neurología , Estudios Prospectivos , Convulsiones/diagnóstico , Espectroscopía Infrarroja Corta
9.
Am J Perinatol ; 34(5): 520-522, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27788536

RESUMEN

Objective This study tested the effectiveness of a video teaching tool in improving identification and classification of encephalopathy in infants. Study Design We developed an innovative video teaching tool to help clinicians improve their skills in interpreting the neonatal neurological examination for grading encephalopathy. Pediatric residents were shown 1-minute video clips demonstrating exam findings in normal neonates and neonates with various degrees of encephalopathy. Findings from five domains were demonstrated: spontaneous activity, level of alertness, posture/tone, reflexes, and autonomic responses. After each clip, subjects were asked to identify whether the exam finding was normal or consistent with mild, moderate, or severe abnormality. Subjects were then directed to a web-based teaching toolkit, containing a compilation of videos demonstrating normal and abnormal findings on the neonatal neurological examination. Immediately after training, subjects underwent posttesting, again identifying exam findings as normal, mild, moderate, or severe abnormality. Results Residents improved in their overall ability to identify and classify neonatal encephalopathy after viewing the teaching tool. In particular, the identification of abnormal spontaneous activity, reflexes, and autonomic responses were most improved. Conclusion This pretest/posttest evaluation of an educational tool demonstrates that after viewing our toolkit, pediatric residents were able to improve their overall ability to detect neonatal encephalopathy.


Asunto(s)
Encefalopatías/diagnóstico , Internado y Residencia , Pediatría/educación , Materiales de Enseñanza , Encefalopatías/clasificación , Humanos , Recién Nacido , Internet , Examen Neurológico , Grabación en Video
10.
Jt Comm J Qual Patient Saf ; 50(1): 66-74, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37718146

RESUMEN

BACKGROUND: The telementoring Project ECHO (Extension for Community Healthcare Outcomes) model has been shown to improve disease management in diabetes in many underserved communities. The authors aim to evaluate if ECHO could also be an effective tool for quality improvement (QI) of diabetes care in these communities. METHODS: Thirteen clinics in underserved communities in California and Florida participating in Project ECHO Diabetes were recruited for a 12-month QI program. The program provided weekly tele-education sessions, including a didactic presentation and case-based discussion. In addition, clinics chose their own set of quality measures to improve and met remotely to discuss their efforts, successes, and setbacks every quarter with mentorship from QI experts. RESULTS: Of the 31 QI initiatives attempted by different clinics, all had either made improvements (25 initiatives, 80.6%) or were in the process of making improvements (6 initiatives, 19.4%) in structural, process, and outcome measures. Examples of these measures include whether clinics have protocols to identify high-risk patients (structure), numbers of continuous glucose monitor prescriptions submitted by the clinics (process), and percentage of patients with diabetes whose most recent HbA1c are > 9% (outcome). For one measure, 40.0% of the clinics had achieved a higher percentage of cumulative HbA1c measurement in the third quarter of the year, compared to the fourth quarter in the previous year. The cost of QI implementation varied widely due to different number of personnel involved across sites. CONCLUSION: A QI program delivered via Project ECHO Diabetes can facilitate quality improvements in underserved communities.


Asunto(s)
Diabetes Mellitus , Mejoramiento de la Calidad , Humanos , Hemoglobina Glucada , Diabetes Mellitus/terapia , Glucemia
11.
Phys Imaging Radiat Oncol ; 30: 100568, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38585372

RESUMEN

Background and purpose: The [18]F-fluoroethyl-l-tyrosine (FET) PET in Glioblastoma (FIG) study is an Australian prospective, multi-centre trial evaluating FET PET for newly diagnosed glioblastoma management. The Radiation Oncology credentialing program aimed to assess the feasibility in Radiation Oncologist (RO) derivation of standard-of-care target volumes (TVMR) and hybrid target volumes (TVMR+FET) incorporating pre-defined FET PET biological tumour volumes (BTVs). Materials and methods: Central review and analysis of TVMR and TVMR+FET was undertaken across three benchmarking cases. BTVs were pre-defined by a sole nuclear medicine expert. Intraclass correlation coefficient (ICC) confidence intervals (CIs) evaluated volume agreement. RO contour spatial and boundary agreement were evaluated (Dice similarity coefficient [DSC], Jaccard index [JAC], overlap volume [OV], Hausdorff distance [HD] and mean absolute surface distance [MASD]). Dose plan generation (one case per site) was assessed. Results: Data from 19 ROs across 10 trial sites (54 initial submissions, 8 resubmissions requested, 4 conditional passes) was assessed with an initial pass rate of 77.8 %; all resubmissions passed. TVMR+FET were significantly larger than TVMR (p < 0.001) for all cases. RO gross tumour volume (GTV) agreement was moderate-to-excellent for GTVMR (ICC = 0.910; 95 % CI, 0.708-0.997) and good-to-excellent for GTVMR+FET (ICC = 0.965; 95 % CI, 0.871-0.999). GTVMR+FET showed greater spatial overlap and boundary agreement compared to GTVMR. For the clinical target volume (CTV), CTVMR+FET showed lower average boundary agreement versus CTVMR (MASD: 1.73 mm vs. 1.61 mm, p = 0.042). All sites passed the planning exercise. Conclusions: The credentialing program demonstrated feasibility in successful credentialing of 19 ROs across 10 sites, increasing national expertise in TVMR+FET delineation.

12.
Water (Basel) ; 15(22): 1-12, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38264201

RESUMEN

This article provides an overview of the bioremediation of groundwater plumes containing admixtures of chlorinated volatile organic compounds (CVOCs) and 1,4-dioxane. The remediation of these plumes has historically focused on the reductive dechlorination of the CVOCs. Many of the remaining plumes are relatively large, and contaminant concentrations are diluted below the concentrations that can sustain reductive dechlorination. Cometabolic processes can decrease contaminant concentrations below the thresholds needed to support direct metabolism but typically require the addition of a substrate, such as high-purity propane. Relatively intensive site characterization and monitoring is necessary to implement bioremediation.

13.
Remediation (N Y) ; 32(1-2): 97-118, 2022 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-35539433

RESUMEN

Management of large, dilute groundwater plumes of comingled chlorinated volatile organic compounds (CVOCs) and 1,4-dioxane (dioxane) is problematic due to chemical, hydrogeologic and economic concerns. The US Environmental Protection Agency (US EPA) has conducted research on the management of CVOC plumes for many years, and more recently dioxane. US EPA research on monitored natural attenuation (MNA) of CVOC plumes was reviewed by a science advisory board in 2001. Specific additional research was recommended and has been addressed in a series of US EPA reports produced over almost two decades. These reports are summarized in this document along with supporting information including evidence of biological degradation of dioxane. Based on the summarized reports, US EPA work documented elsewhere, and the work of others, under appropriate conditions MNA or augmented MNA remain viable management options for these plumes. Unlike MNA of plumes containing only CVOCs, however, MNA of large dilute comingled plumes should be expected to occur by cometabolic oxidation rather than direct metabolic processes.

14.
J Speech Lang Hear Res ; 65(10): 3776-3788, 2022 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-36194778

RESUMEN

PURPOSE: The purpose of this study is to characterize the local (utterance-level) temporal regularities of child-directed speech (CDS) that might facilitate phonological development in Spanish, classically termed a syllable-timed language. METHOD: Eighteen female adults addressed their 4-year-old children versus other adults spontaneously and also read aloud (CDS vs. adult-directed speech [ADS]). We compared CDS and ADS speech productions using a spectrotemporal model (Leong & Goswami, 2015), obtaining three temporal metrics: (a) distribution of modulation energy, (b) temporal regularity of stressed syllables, and (c) syllable rate. RESULTS: CDS was characterized by (a) significantly greater modulation energy in the lower frequencies (0.5-4 Hz), (b) more regular rhythmic occurrence of stressed syllables, and (c) a slower syllable rate than ADS, across both spontaneous and read conditions. DISCUSSION: CDS is characterized by a robust local temporal organization (i.e., within utterances) with amplitude modulation bands aligning with delta and theta electrophysiological frequency bands, respectively, showing greater phase synchronization than in ADS, facilitating parsing of stress units and syllables. These temporal regularities, together with the slower rate of production of CDS, might support the automatic extraction of phonological units in speech and hence support the phonological development of children. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.21210893.


Asunto(s)
Percepción del Habla , Habla , Adulto , Preescolar , Familia , Femenino , Humanos , Lenguaje , Lectura , Habla/fisiología , Percepción del Habla/fisiología
15.
Antimicrob Agents Chemother ; 55(5): 2344-51, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21343467

RESUMEN

Ceftaroline, the active component of the prodrug ceftaroline fosamil, is a novel broad-spectrum cephalosporin with bactericidal activity against Gram-positive and -negative isolates. This study evaluated the potential for ceftaroline and comparator antibiotics to select for clones of Streptococcus pneumoniae, Streptococcus pyogenes, Haemophilus influenzae, Moraxella catarrhalis, Klebsiella pneumoniae, Staphylococcus aureus, and Enterococcus faecalis with elevated MICs. S. pneumoniae and S. pyogenes isolates in the present study were highly susceptible to ceftaroline (MIC range, 0.004 to 0.25 µg/ml). No streptococcal strains yielded ceftaroline clones with increased MICs (defined as an increase in MIC of >4-fold) after 50 daily passages. Ceftaroline MICs for H. influenzae and M. catarrhalis were 0.06 to 2 µg/ml for four strains and 8 µg/ml for a ß-lactamase-positive, efflux-positive H. influenzae with a mutation in L22. One H. influenzae clone with an increased ceftaroline MIC (quinolone-resistant, ß-lactamase-positive) was recovered after 20 days. The ceftaroline MIC for this isolate increased 16-fold, from 0.06 to 1 µg/ml. MICs for S. aureus ranged from 0.25 to 1 µg/ml. No S. aureus isolates tested with ceftaroline had clones with increased MIC (>4-fold) after 50 passages. Two E. faecalis isolates tested had ceftaroline MICs increased from 1 to 8 µg/ml after 38 days and from 4 to 32 µg/ml after 41 days, respectively. The parental ceftaroline MIC for the one K. pneumoniae extended-spectrum ß-lactamase-negative isolate tested was 0.5 µg/ml and did not change after 50 daily passages.


Asunto(s)
Antibacterianos/farmacología , Cefalosporinas/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Enterococcus faecalis/efectos de los fármacos , Haemophilus influenzae/efectos de los fármacos , Klebsiella pneumoniae/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Moraxella catarrhalis/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pyogenes/efectos de los fármacos , Ceftarolina
16.
Antimicrob Agents Chemother ; 55(4): 1787-91, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21245439

RESUMEN

Against 33 Gram-positive and -negative bacteria, NXL 103 MICs were 0.03 to 1 µg/ml. NXL 103 was bactericidal by 12 h at 2 × MIC against all 5 pneumococci and at 2 × MIC after 24 h against all 5 group A and B ß-hemolytic streptococci. NXL 103 was bactericidal against all 8 Haemophilus influenzae strains at 2 × MIC and all 5 Moraxella catarrhalis strains at 4 × MIC after 24 h but was mainly bacteriostatic against 5 methicillin-resistant Staphylococcus aureus strains. After the exposure of one strain of each species to NXL 103 for 10 daily subcultures, the MICs remained within ± 1 dilution.


Asunto(s)
Antibacterianos/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Estreptograminas/farmacología , Haemophilus influenzae/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/efectos de los fármacos , Streptococcus pneumoniae/efectos de los fármacos
17.
Antimicrob Agents Chemother ; 55(5): 2417-9, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21343445

RESUMEN

We tested the MICs of fusidic acid (CEM-102) plus other agents against 40 methicillin-resistant Staphylococcus aureus (MRSA) isolates from cystic fibrosis patients and the activities of fusidic acid with or without tobramycin or amikacin against Pseudomonas aeruginosa, MRSA, and Burkholderia cepacia isolates from cystic fibrosis patients in a 24-h time-kill study. Fusidic acid was potent (MICs, 0.125 to 0.5 µg/ml; a single 500-mg dose of fusidic acid at 8 h averaged 8 to 12. 5 µg/ml with 91 to 97% protein binding) against all MRSA strains. No antagonism was observed; synergy occurred for one MRSA strain treated with fusidic acid plus tobramycin.


Asunto(s)
Amicacina/farmacología , Burkholderia cepacia/efectos de los fármacos , Fibrosis Quística/microbiología , Ácido Fusídico/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Tobramicina/farmacología , Sinergismo Farmacológico , Humanos
18.
Environ Sci Pollut Res Int ; 28(27): 35811-35821, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33675494

RESUMEN

Acetaldehyde plays an important role in oxidative cycles in the troposphere. Estimates of its air-water flux are important in global models. Biological degradation is believed to be the dominant loss process in water, but there have been few measurements, none in estuaries. Acetaldehyde degradation rates were measured in surface waters at the inflow to the Upper Newport Back Bay estuary in Orange County, Southern California, USA, over a 6-month period including the rainy winter season. Deuterated acetaldehyde was added to filtered and unfiltered water samples incubated in glass syringes, and its loss analyzed by purge and trap gas chromatography mass spectrometry. Filtered samples showed no significant degradation, suggesting that particle-mediated degradation is the dominant removal process. Correlation between measured degradation rate constants in unfiltered incubations and bacteria counts suggests the loss is due to microorganisms. Degradation in unfiltered samples followed first-order kinetics, with rate constants ranging from 0.0006 to 0.025 min-1 (k; average 0.0043 ± 0.006 min-1). Turnover (1/k) ranged from 40 to 1667 min, consistent with prior studies in coastal waters. Acetaldehyde concentrations in the estuary are estimated to range from 30 to ~500 nM (average ~250 nM). Results suggest the estuary is a source of acetaldehyde to the atmosphere.


Asunto(s)
Estuarios , Contaminantes Químicos del Agua , Acetaldehído , California , Monitoreo del Ambiente , Agua de Mar , Contaminantes Químicos del Agua/análisis
19.
Antimicrob Agents Chemother ; 54(1): 230-8, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19884376

RESUMEN

CEM-101 had MIC ranges of 0.002 to 0.016 microg/ml against macrolide-susceptible pneumococci and 0.004 to 1 microg/ml against macrolide-resistant phenotypes. Only 3 strains with erm(B), with or without mef(A), had CEM-101 MICs of 1 microg/ml, and 218/221 strains had CEM-101 MICs of 64 microg/ml, while 17/19 strains had telithromycin MICs of 4 to 16 microg/ml; CEM-101 MICs were 0.015 to 1 microg/ml. By comparison, erm(A) and mef(A) strains had CEM-101 MICs of 0.015 to 0.5 microg/ml, clindamycin and telithromycin MICs of 64 microg/ml. Pneumococcal multistep resistance studies showed that although CEM-101 yielded clones with higher MICs for all eight strains tested, seven of eight strains had clones with CEM-101 MICs that rose from 0.004 to 0.03 microg/ml (parental strains) to 0.06 to 0.5 microg/ml (resistant clones); for only one erm(B) mef(A) strain with a parental MIC of 1 microg/ml was there a resistant clone with a MIC of 32 microg/ml, with no detectable mutations in the L4, L22, or 23S rRNA sequence. Among two of five S. pyogenes strains tested, CEM-101 MICs rose from 0.03 to 0.25 microg/ml, and only for the one strain with erm(B) did CEM-101 MICs rise from 1 to 8 microg/ml, with no changes occurring in any macrolide resistance determinant. CEM-101 had low MICs as well as low potential for the selection of resistant mutants, independent of bacterial species or resistance phenotypes in pneumococci and S. pyogenes.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Macrólidos/farmacología , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pyogenes/efectos de los fármacos , Triazoles/farmacología , Pruebas de Sensibilidad Microbiana , Penicilina G/farmacología
20.
Environ Sci Pollut Res Int ; 27(11): 12673-12682, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32006326

RESUMEN

Interest in understanding the cycling of ethanol in the environment has grown as ethanol use as a gasoline additive has increased. The production of acetaldehyde from ethanol was measured in Southern California coastal seawater. The rate of increase of acetaldehyde was positively correlated with the rate constant for ethanol biodegradation and bacteria count and was consistent with two consecutive first-order reactions where acetaldehyde is first biologically produced from ethanol then consumed. Correlation with bacteria counts suggested that acetaldehyde degradation was also a biological process. The rate constants for acetaldehyde production from ethanol and acetaldehyde loss averaged 3.0 ± 3.4 × 10-3 min-1 and 2.3 ± 4.5 × 10-2 min-1 respectively. The branching ratio for acetaldehyde production from ethanol was 0.46 ± 0.26 and estimated acetaldehyde biological production rates ranged from 0.022 to 0.800 nM min-1. With high bacterial counts, biological production rates from ethanol exceeded photochemical production rates from chromophoric dissolved organic matter. Overall, acetaldehyde production rates were larger than biodegradation rates, suggesting these waters are a source of acetaldehyde to the atmosphere. Extrapolation to higher ethanol concentrations associated with spills suggests that the production rate of acetaldehyde will initially increase and then decrease as ethanol concentrations increase.


Asunto(s)
Acetaldehído , Etanol , Biodegradación Ambiental , Agua de Mar
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