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1.
Clin Case Rep ; 10(8): e6159, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35937006

RESUMEN

Patients undergoing cochlear implant after prior radical mastoidectomy are at increased risk of device infection requiring device explant. Various techniques including two-stage operations have been used. We report the novel technique with use of a vascularized fascia lata free flap for a patient undergoing cochlear implantation with radical mastoidectomy.

2.
Int J Pediatr Otorhinolaryngol ; 159: 111206, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35759915

RESUMEN

OBJECTIVES: Transoral robotic surgery in adults confers excellent results and decreased morbidity. Application of these techniques has not yet been rigorously investigated in children. The goal of this study is to evaluate the feasibility of a flexible robotic surgical system in a pediatric population. METHODS: This was a non-randomized, non-blinded, prospective clinical trial. An Investigational Device Exemption was obtained from the FDA. Patients 8-12 years old scheduled for tonsillectomy and adenoidectomy between February and December 2019 at an academic tertiary care children's hospital were included. Exclusion criteria included pulmonary or vascular conditions posing risks for extended anesthesia, or a smaller mouth opening than the instrumentation (28 mm × 15 mm). Tonsillectomy was completed with standard monopolar cautery. After the surgery was complete, the robot was utilized for evaluation and assessment of exposure. A pediatric anesthesiologist screened patients for tolerance of additional anesthesia (up to 15 min). A flexible robotic surgical system, the MedRobotics Flex® Robotic System, was used to visualize and access the tonsillar fossa, posterior pharynx, base of tongue, epiglottis and false vocal folds. Visualization and access were graded on a five-point Likert scale. RESULTS: A total of ten patients, eight males and two females, with obstructive sleep apnea (OSA) or sleep disordered breathing (SDB) were recruited in 2019. One patient did not complete the study due to equipment malfunction. The average patient demographics were: age 10.1 years (8.6-11.8 years), height 142.4 cm (127-164.9 cm), weight 47.5 kg (24.4-84.5 kg), and BMI 22.6 (13.9-31.0). Study time averaged 10.3 min (5-13 min). The tonsillar fossa, base of tongue, and posterior pharynx were visualized completely and easily accessed with the robotic instruments. The epiglottis and false vocal folds were visualized and accessed in 66% and 55% of patients, respectively. There were no adverse effects. CONCLUSIONS: This study demonstrated that a flexible robotic surgical system is feasible for use in children 8-12 years of age when performing otolaryngology - head and neck surgery procedures of the oropharynx and larynx.


Asunto(s)
Procedimientos Quirúrgicos Robotizados , Robótica , Tonsilectomía , Adulto , Niño , Estudios de Factibilidad , Femenino , Humanos , Masculino , Estudios Prospectivos , Procedimientos Quirúrgicos Robotizados/efectos adversos , Procedimientos Quirúrgicos Robotizados/métodos , Tonsilectomía/métodos
3.
SAGE Open Med Case Rep ; 10: 2050313X211070520, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35024149

RESUMEN

Glomus tumors are benign hyperplasia of glomus bodies, and they are rarely found in the head and neck. The middle ear is an exceptionally rare site for a true glomus tumor, and there are only three previously reported cases in this location. Glomus tumors are etiologically different than glomus tympanicum, which are paragangliomas of the middle ear that are often mistakenly referred to as "glomus tumors." This is a common misconception due to the "glomus" misnomer. We report a case of a patient diagnosed with a middle ear glomangioma after initially presenting to our clinic with tinnitus and hearing loss. The mass was surgically removed through a transcanal approach with carbon dioxide laser and sharp dissection. Literature review is also reported and revealed similar presentations in patients with middle ear glomangiomas.

4.
Water Res ; 205: 117685, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34601359

RESUMEN

A continuous-variable Bayesian network (cBN) model is used to link watershed development and climate change to stream ecosystem indicators. A graphical model, reflecting our understanding of the connections between climate change, weather condition, loss of natural land cover, stream flow characteristics, and stream ecosystem indicators is used as the basis for selecting flow metrics for predicting macroinvertebrate-based indicators. Selected flow metrics were then linked to variables representing watershed development and climate change. We fit the model to data from two river basins in southeast US and the resulting model was used to simulate future stream ecological conditions using projected future climate and development scenarios. The three climate models predicted varying ecological condition trajectories, but similar worst-case ecological conditions. The established modeling approach couples mechanistic understanding with field data to develop predictions of management-relevant variables across a heterogeneous landscape. We discussed the transferability of the modeling approach.


Asunto(s)
Ecosistema , Ríos , Teorema de Bayes , Cambio Climático , Modelos Teóricos
5.
Ann Otol Rhinol Laryngol ; 130(12): 1400-1406, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33834872

RESUMEN

OBJECTIVE: Report a series of cases in which patients have concomitant superior semicircular canal dehiscence (SSCD) and a dehiscent tegmen tympani with Dural contact to the malleus head (DCMH). METHODS: An analysis of radiologic and audiologic data in 4 patients who presented with SSCD and DCMH at a tertiary care institution. A pertinent literature review was performed. RESULTS: Four patients (5 ears) had SSCD and DCMH. In 3 patients with unilateral DCMH, the mean maximum air-bone gap was 15 dB in the ear with DCMH compared to 50 dB in the ear without DCMH. Of the 5 ears with DCMH, the mean air conduction threshold at 250 Hz was 17 dB compared to 42 dB in the 3 ears without DCMH. CONCLUSIONS: We report the findings of DCMH in a series of 4 patients with bilateral SSCD. This limited series suggests that ears with SSCD and DCMH have less of an air-bone gap than would be expected, as 1 would expect an additive effect of DCMH and SSCD on the air-bone gap.


Asunto(s)
Conducción Ósea/fisiología , Pérdida Auditiva Conductiva/etiología , Audición/fisiología , Martillo/diagnóstico por imagen , Dehiscencia del Canal Semicircular/diagnóstico , Tomografía Computarizada por Rayos X/métodos , Adulto , Audiometría de Tonos Puros , Femenino , Pérdida Auditiva Conductiva/diagnóstico , Pérdida Auditiva Conductiva/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Dehiscencia del Canal Semicircular/complicaciones , Dehiscencia del Canal Semicircular/fisiopatología
6.
Int J Pediatr Otorhinolaryngol ; 141: 110566, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33348124

RESUMEN

OBJECTIVE: To compare tracheoscopy and chest radiograph measurements of tracheostomy tube position in infants. STUDY DESIGN: Retrospective chart review. SETTING: Otolaryngology Department at Penn State Milton S. Hershey Medical Center. SUBJECTS AND METHODS: All cases of pediatric patients who underwent tracheotomy at less than 1 year of age from 2014 to 2019 were reviewed. Patients were included if they had both intraoperative measurement of tracheostomy tube position relative to the carina by tracheoscopy and postoperative chest radiograph. Documented intraoperative findings were compared to measurements made on chest radiograph by an attending radiologist blinded to the intraoperative measurements. RESULTS: The study included 66 patients; 30 patients (14:16, M:F) had available data. The mean distance from the distal tracheostomy tube to the carina measured by tracheoscopy was 8.88 mm (range, 3.5-20 mm) and measured radiographically was 11.71 mm (range, 2.4-23.3 mm). The mean difference between the measurements was 2.82 mm (p-value = 0.016). Ninety percent (n = 27) of patients had measurements that differed by greater than 2 mm; 53% (n = 16) had measurements that differed by 5 mm and 1% (n = 3) had measurements differing by greater than 10 mm. CONCLUSION: In the infant population, significant discrepancy was found between direct tracheoscopy and chest radiograph measurements of the tracheostomy tube position. Measurements obtained by chest radiographs tend to overestimate the relative distance of the distal tracheostomy tube to the carina as compared to that of tracheoscopy. Clinical decisions regarding changes to tracheostomy tube sizes should mostly rely on tracheoscopy performed with the patient supine.


Asunto(s)
Traqueostomía , Traqueotomía , Niño , Humanos , Lactante , Radiografía , Estudios Retrospectivos , Rayos X
7.
Otolaryngol Head Neck Surg ; 162(6): 797-799, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32286916

RESUMEN

There are insufficient data regarding the safety of otologic procedures in the setting of the coronavirus disease 2019 (COVID-19) pandemic. Given the proclivity for respiratory pathogens to involve the middle ear and the significant aerosolization associated with many otologic procedures, safety precautions should follow current recommendations for procedures involving the upper airway. Until preoperative diagnostic testing becomes standardized and readily available, elective cases should be deferred and emergent/urgent cases should be treated as high risk for COVID-19 exposure. Necessary otologic procedures on positive, suspected, or unknown COVID-19 status patients should be performed using enhanced personal protective equipment, including an N95 respirator and eye protection or powered air-purifying respirator (PAPR, preferred), disposable cap, disposable gown, and gloves. Powered instrumentation should be avoided unless absolutely necessary, and if performed, PAPR or sealed eye protection is recommended.


Asunto(s)
Infecciones por Coronavirus/epidemiología , Transmisión de Enfermedad Infecciosa/prevención & control , Procedimientos Quirúrgicos Otológicos/normas , Pandemias/estadística & datos numéricos , Equipo de Protección Personal/estadística & datos numéricos , Neumonía Viral/epidemiología , Administración de la Seguridad , COVID-19 , Control de Enfermedades Transmisibles/normas , Infecciones por Coronavirus/prevención & control , Femenino , Salud Global , Humanos , Masculino , Salud Laboral , Evaluación de Resultado en la Atención de Salud , Pandemias/prevención & control , Seguridad del Paciente , Selección de Paciente , Neumonía Viral/prevención & control , Guías de Práctica Clínica como Asunto , Estados Unidos
8.
Otolaryngol Head Neck Surg ; 162(6): 783-794, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32340588

RESUMEN

OBJECTIVE: To review the impact of coronavirus disease 2019 (COVID-19) on pediatric otolaryngology and provide recommendations for the management of children during the COVID-19 pandemic. DATA SOURCES: Clinical data were derived from peer-reviewed primary literature and published guidelines from national or international medical organizations. Preprint manuscripts and popular media articles provided background information and illustrative examples. METHODS: Included manuscripts were identified via searches using PubMed, MEDLINE, and Google Scholar, while organizational guidelines and popular media articles were identified using Google search queries. Practice guidelines were developed via consensus among all authors based on peer-reviewed manuscripts and national or international health care association guidelines. Strict objective criteria for inclusion were not used due to the rapidly changing environment surrounding the COVID-19 pandemic and a paucity of rigorous empirical evidence. CONCLUSIONS: In the face of the COVID-19 pandemic, medical care must be judiciously allocated to treat the most severe conditions while minimizing the risk of long-term sequelae and ensuring patient, physician, and health care worker safety. IMPLICATIONS FOR PRACTICE: The COVID-19 pandemic will have a profound short- and long-term impact on health care worldwide. Although the full repercussions of this disease have yet to be realized, the outlined recommendations will guide otolaryngologists in the treatment of pediatric patients in the face of an unprecedented global health crisis.


Asunto(s)
Control de Enfermedades Transmisibles/normas , Infecciones por Coronavirus/epidemiología , Procedimientos Quirúrgicos Electivos/estadística & datos numéricos , Procedimientos Quirúrgicos Otorrinolaringológicos/estadística & datos numéricos , Pandemias/estadística & datos numéricos , Neumonía Viral/epidemiología , Guías de Práctica Clínica como Asunto/normas , Betacoronavirus , COVID-19 , Niño , Preescolar , Infecciones por Coronavirus/diagnóstico , Procedimientos Quirúrgicos Electivos/normas , Salud Global , Humanos , Masculino , Otolaringología/métodos , Otolaringología/normas , Procedimientos Quirúrgicos Otorrinolaringológicos/métodos , Evaluación de Resultado en la Atención de Salud , Pandemias/prevención & control , Seguridad del Paciente , Selección de Paciente , Pediatría/normas , Neumonía Viral/diagnóstico , Medición de Riesgo , SARS-CoV-2 , Estados Unidos
9.
Environ Sci Technol ; 54(9): 5509-5519, 2020 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-32309929

RESUMEN

Streambed sediment is commonly analyzed to assess occurrence of hydrophobic pesticides and risks to aquatic communities. However, stream biofilms also have the potential to accumulate pesticides and may be consumed by aquatic organisms. To better characterize risks to aquatic life, the U.S. Geological Survey Regional Stream Quality Assessment measured 93 current-use and 3 legacy pesticides in bed sediment and biofilm from 54 small streams in California across a range of land-use settings. On average, 4 times as many current-use pesticides were detected in biofilm at a site (median of 2) as in sediment (median of 0.5). Of 31 current-use pesticides detected, 20 were detected more frequently in biofilm than in sediment and 10 with equal frequency. Pyrethroids as a class were the most potentially toxic to benthic invertebrates, and of the 9 pyrethroids detected, 7 occurred more frequently in biofilm than sediment. We constructed general additive models to investigate relations between pesticides and 6 metrics of benthic community structure. Pesticides in biofilm improved fit in 4 of the 6 models, and pesticides in sediment improved fit in 2. The results indicate that the sampling of stream biofilms can complement bed-sediment sampling by identification of more current-use pesticides present and better estimation of ecological risks.


Asunto(s)
Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , Animales , Biopelículas , Biota , Monitoreo del Ambiente , Ríos
11.
PLoS One ; 11(1): e0146724, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26796147

RESUMEN

Climate change is driving rapid changes in environmental conditions and affecting population and species' persistence across spatial and temporal scales. Integrating climate change assessments into biological resource management, such as conserving endangered species, is a substantial challenge, partly due to a mismatch between global climate forecasts and local or regional conservation planning. Here, we demonstrate how outputs of global climate change models can be downscaled to the watershed scale, and then coupled with ecophysiological metrics to assess climate change effects on organisms of conservation concern. We employed models to estimate future water temperatures (2010-2099) under several climate change scenarios within the large heterogeneous San Francisco Estuary. We then assessed the warming effects on the endangered, endemic Delta Smelt, Hypomesus transpacificus, by integrating localized projected water temperatures with thermal sensitivity metrics (tolerance, spawning and maturation windows, and sublethal stress thresholds) across life stages. Lethal temperatures occurred under several scenarios, but sublethal effects resulting from chronic stressful temperatures were more common across the estuary (median >60 days above threshold for >50% locations by the end of the century). Behavioral avoidance of such stressful temperatures would make a large portion of the potential range of Delta Smelt unavailable during the summer and fall. Since Delta Smelt are not likely to migrate to other estuaries, these changes are likely to result in substantial habitat compression. Additionally, the Delta Smelt maturation window was shortened by 18-85 days, revealing cumulative effects of stressful summer and fall temperatures with early initiation of spring spawning that may negatively impact fitness. Our findings highlight the value of integrating sublethal thresholds, life history, and in situ thermal heterogeneity into global change impact assessments. As downscaled climate models are becoming widely available, we conclude that similar assessments at management-relevant scales will improve the scientific basis for resource management decisions.


Asunto(s)
Cambio Climático , Clima , Especies en Peligro de Extinción , Estuarios , Osmeriformes/fisiología , Animales , California , Ecosistema , Modelos Teóricos , Estaciones del Año , Temperatura
12.
Environ Monit Assess ; 187(1): 4086, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25384371

RESUMEN

We used boosted regression trees (BRT) to model stream biological condition as measured by benthic macroinvertebrate taxonomic completeness, the ratio of observed to expected (O/E) taxa. Models were developed with and without exclusion of rare taxa at a site. BRT models are robust, requiring few assumptions compared with traditional modeling techniques such as multiple linear regression. The BRT models were constructed to provide baseline support to stressor delineation by identifying natural physiographic and human land use gradients affecting stream biological condition statewide and for eight ecological regions within the state, as part of the development of numerical biological objectives for California's wadeable streams. Regions were defined on the basis of ecological, hydrologic, and jurisdictional factors and roughly corresponded with ecoregions. Physiographic and land use variables were derived from geographic information system coverages. The model for the entire state (n = 1,386) identified a composite measure of anthropogenic disturbance (the sum of urban, agricultural, and unmanaged roadside vegetation land cover) within the local watershed as the most important variable, explaining 56% of the variance in O/E values. Models for individual regions explained between 51 and 84% of the variance in O/E values. Measures of human disturbance were important in the three coastal regions. In the South Coast and Coastal Chaparral, local watershed measures of urbanization were the most important variables related to biological condition, while in the North Coast the composite measure of human disturbance at the watershed scale was most important. In the two mountain regions, natural gradients were most important, including slope, precipitation, and temperature. The remaining three regions had relatively small sample sizes (n ≤ 75 sites) and had models that gave mixed results. Understanding the spatial scale at which land use and land cover affect taxonomic completeness is imperative for sound management. Our results suggest that invertebrate taxonomic completeness is affected by human disturbance at the statewide and regional levels, with some differences among regions in the importance of natural gradients and types of human disturbance. The construction and application of models similar to the ones presented here could be useful in the planning and prioritization of actions for protection and conservation of biodiversity in California streams.


Asunto(s)
Biodiversidad , Ecosistema , Monitoreo del Ambiente/métodos , Modelos Biológicos , Ríos/química , California , Clima , Árboles de Decisión , Sistemas de Información Geográfica , Urbanización
13.
PLoS One ; 9(3): e90944, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24675770

RESUMEN

We developed independent predictive disturbance models for a full regional data set and four individual ecoregions (Full Region vs. Individual Ecoregion models) to evaluate effects of spatial scale on the assessment of human landscape modification, on predicted response of stream biota, and the effect of other possible confounding factors, such as watershed size and elevation, on model performance. We selected macroinvertebrate sampling sites for model development (n = 591) and validation (n = 467) that met strict screening criteria from four proximal ecoregions in the northeastern U.S.: North Central Appalachians, Ridge and Valley, Northeastern Highlands, and Northern Piedmont. Models were developed using boosted regression tree (BRT) techniques for four macroinvertebrate metrics; results were compared among ecoregions and metrics. Comparing within a region but across the four macroinvertebrate metrics, the average richness of tolerant taxa (RichTOL) had the highest R(2) for BRT models. Across the four metrics, final BRT models had between four and seven explanatory variables and always included a variable related to urbanization (e.g., population density, percent urban, or percent manmade channels), and either a measure of hydrologic runoff (e.g., minimum April, average December, or maximum monthly runoff) and(or) a natural landscape factor (e.g., riparian slope, precipitation, and elevation), or a measure of riparian disturbance. Contrary to our expectations, Full Region models explained nearly as much variance in the macroinvertebrate data as Individual Ecoregion models, and taking into account watershed size or elevation did not appear to improve model performance. As a result, it may be advantageous for bioassessment programs to develop large regional models as a preliminary assessment of overall disturbance conditions as long as the range in natural landscape variability is not excessive.


Asunto(s)
Invertebrados , Modelos Teóricos , Animales , Reproducibilidad de los Resultados
14.
Int J Pediatr Otorhinolaryngol ; 78(1): 10-3, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24275082

RESUMEN

OBJECTIVES: Deep neck abscesses are complex head & neck problems that can lead to significant complications including life threatening infections. It is understood that the pathology of these infections is primarily polymicrobial. Although broad spectrum antibiotics can be effective for small abscesses, larger abscesses can be recalcitrant and difficult to treat with antibiotics. It has been demonstrated for several infectious diseases, including some of head & neck, that biofilm phenotypes present a unique model for recurrence and chronicity of infectious diseases. It is suspected that biofilm phenotypes could play a crucial role in the recalcitrance of large deep neck abscesses. This study presents initial evidence indicating the presence of polymicrobial biofilms in deep neck space infections. METHODS: Fourteen samples obtained via biopsy of abscess walls from deep neck spaces of patients undergoing surgical drainage. Eight patients were male and 6 were female. All but one patient were pediatric with ages ranging from 18 months to 32 years. All samples were processed and analyzed with scanning electron microscopy. RESULTS: Electron micrographs of 12 out of 14 specimens showed discrete biofilm architecture with individual bacteria, both rods and cocci, embedded within the matrix. This was starkly different from tissue surfaces devoid of biofilms. CONCLUSIONS: This initial evidence suggests that biofilm phenotypes could play a role in the pathogenesis and recalcitrance of deep neck infections, particularly in larger abscesses.


Asunto(s)
Fenómenos Fisiológicos Bacterianos , Biopelículas/crecimiento & desarrollo , Absceso Retrofaríngeo/microbiología , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Microscopía Electrónica de Rastreo , Cuello/microbiología , Cuello/cirugía , Adulto Joven
15.
Ann Otol Rhinol Laryngol ; 120(2): 116-22, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21391424

RESUMEN

OBJECTIVES: We performed a systematic review of published literature correlating findings on endoscopic evaluation of the larynx and trachea in the pediatric population with the incidence of gastroesophageal reflux disease. METHODS: Eight articles were identified through a structured PubMed search of English-language literature using the key terms laryngopharyngeal reflux, extraesophageal reflux, and gastroesophageal reflux. A systematic review was performed relating the presence of reflux in the pediatric population to findings on endoscopic airway evaluation. A covariant analysis was performed, and each study was weighted according to the number of available samples in that study as a fraction of the total. Overall odds ratios and confidence intervals were computed for each endoscopic finding on the basis of the documented absence or presence of gastroesophageal reflux disease. RESULTS: A correlation was seen between the endoscopic findings and the presence of reflux. CONCLUSIONS: Arytenoid, postglottic, and vocal fold edema and erythema, lingual tonsil hypertrophy, laryngomalacia, and subglottic stenosis are among the endoscopic findings most frequently identified in patients with gastroesophageal reflux disease. Certain findings commonly encountered on endoscopic evaluation of the larynx and trachea in children who present with respiratory symptoms do indeed demonstrate a correlation with the presence of laryngopharyngeal reflux disease and may indicate the need for antireflux therapy.


Asunto(s)
Reflujo Gastroesofágico/patología , Laringe/patología , Tráquea/patología
16.
Ecol Appl ; 20(5): 1384-401, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20666256

RESUMEN

Responses of benthic macroinvertebrates along gradients of urban intensity were investigated in nine metropolitan areas across the United States. Invertebrate assemblages in metropolitan areas where forests or shrublands were being converted to urban land were strongly related to urban intensity. In metropolitan areas where agriculture and grazing lands were being converted to urban land, invertebrate assemblages showed much weaker or nonsignificant relations with urban intensity because sites with low urban intensity were already degraded by agriculture. Ordination scores, the number of EPT taxa, and the mean pollution-tolerance value of organisms at a site were the best indicators of changes in assemblage condition. Diversity indices, functional groups, behavior, and dominance metrics were not good indicators of urbanization. Richness metrics were better indicators of urban effects than were abundance metrics, and qualitative samples collected from multiple habitats gave similar results to those of single habitat quantitative samples (riffles or woody snags) in all metropolitan areas. Changes in urban intensity were strongly correlated with a set of landscape variables that was consistent across all metropolitan areas. In contrast, the instream environmental variables that were strongly correlated with urbanization and invertebrate responses varied among metropolitan areas. The natural environmental setting determined the biological, chemical, and physical instream conditions upon which urbanization acts and dictated the differences in responses to urbanization among metropolitan areas. Threshold analysis showed little evidence for an initial period of resistance to urbanization. Instead, assemblages were degraded at very low levels of urbanization, and response rates were either similar across the gradient or higher at low levels of urbanization. Levels of impervious cover that have been suggested as protective of streams (5-10%) were associated with significant assemblage degradation and were not protective.


Asunto(s)
Invertebrados/fisiología , Urbanización , Animales , Estados Unidos
17.
Environ Manage ; 35(4): 493-504, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15902444

RESUMEN

We developed a benthic macro-invertebrate index of biological integrity (B-IBI) for the semi-arid and populous southern California coastal region. Potential reference sites were screened from a pool of 275 sites, first with quantitative GIS landscape analysis at several spatial scales and then with local condition assessments (in-stream and riparian) that quantified stressors acting on study reaches. We screened 61 candidate metrics for inclusion in the B-IBI based on three criteria: sufficient range for scoring, responsiveness to watershed and reach-scale disturbance gradients, and minimal correlation with other responsive metrics. Final metrics included: percent collector-gatherer + collector-filterer individuals, percent non-insect taxa, percent tolerant taxa, Coleoptera richness, predator richness, percent intolerant individuals, and EPT richness. Three metrics had lower scores in chaparral reference sites than in mountain reference sites and were scored on separate scales in the B-IBI. Metrics were scored and assembled into a composite B-IBI, which was then divided into five roughly equal condition categories. PCA analysis was used to demonstrate that the B-IBI was sensitive to composite stressor gradients; we also confirmed that the B-IBI scores were not correlated with elevation, season, or watershed area. Application of the B-IBI to an independent validation dataset (69 sites) produced results congruent with the development dataset and a separate repeatability study at four sites in the region confirmed that the B-IBI scoring is precise. The SoCal B-IBI is an effective tool with strong performance characteristics and provides a practical means of evaluating biotic condition of streams in southern coastal California.


Asunto(s)
Conservación de los Recursos Naturales , Monitoreo del Ambiente/métodos , Ríos , Animales , Biodiversidad , California , Invertebrados , Nitrógeno/análisis , Fósforo/análisis , Análisis de Componente Principal , Contaminación del Agua/prevención & control , Abastecimiento de Agua
18.
Stroke ; 34(2): 571-4, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12574578

RESUMEN

BACKGROUND AND PURPOSE: Hyperbaric oxygen therapy (HBO) has promise as a treatment for acute stroke. This study was conducted to evaluate the efficacy, safety, and feasibility of using HBO in acute ischemic stroke. METHODS: We conducted a randomized, prospective, double-blind, sham-controlled pilot study of 33 patients presenting with acute ischemic stroke who did not receive thrombolytics over a 24-month period. Patients were randomized to treatment for 60 minutes in a monoplace hyperbaric chamber pressurized with 100% O2 to 2.5-atm absolute (ATA) in the HBO group or 1.14 ATA in the sham group. Primary outcomes measured included percentage of patients with improvement at 24 hours (National Institutes of Health Stroke Scale [NIHSS]) and 90 days (NIHSS, Barthel Index, modified Rankin Scale, Glasgow Outcome Scale). Secondary measurements included complications of treatment and mortality at 90 days. RESULTS: Baseline demographics were similar in both groups. There were no differences between the groups at 24 hours (P=0.44). At 3 months, however, a larger percentage of the sham patients had a good outcome defined by their stroke scores compared with the HBO group (NIHSS, 80% versus 31.3%; P=0.04; Barthel Index, 81.8% versus 50%; P=0.12; modified Rankin Scale, 81.8% versus 31.3%; P=0.02; Glasgow Outcome Scale, 90.9% versus 37.5%; P=0.01) with loss of statistical significance in a intent-to-treat analysis. CONCLUSIONS: Although our HBO protocol appears feasible and safe, it does not appear to be beneficial and may be harmful in patients with acute ischemic stroke.


Asunto(s)
Isquemia Encefálica/terapia , Oxigenoterapia Hiperbárica , Accidente Cerebrovascular/terapia , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Cámaras de Exposición Atmosférica , Presión Atmosférica , Isquemia Encefálica/complicaciones , Método Doble Ciego , Estudios de Factibilidad , Femenino , Escala de Consecuencias de Glasgow , Humanos , Oxigenoterapia Hiperbárica/efectos adversos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/complicaciones , Resultado del Tratamiento
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