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1.
Nature ; 627(8004): 564-571, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38418889

RESUMEN

Numerous studies have shown reduced performance in plants that are surrounded by neighbours of the same species1,2, a phenomenon known as conspecific negative density dependence (CNDD)3. A long-held ecological hypothesis posits that CNDD is more pronounced in tropical than in temperate forests4,5, which increases community stabilization, species coexistence and the diversity of local tree species6,7. Previous analyses supporting such a latitudinal gradient in CNDD8,9 have suffered from methodological limitations related to the use of static data10-12. Here we present a comprehensive assessment of latitudinal CNDD patterns using dynamic mortality data to estimate species-site-specific CNDD across 23 sites. Averaged across species, we found that stabilizing CNDD was present at all except one site, but that average stabilizing CNDD was not stronger toward the tropics. However, in tropical tree communities, rare and intermediate abundant species experienced stronger stabilizing CNDD than did common species. This pattern was absent in temperate forests, which suggests that CNDD influences species abundances more strongly in tropical forests than it does in temperate ones13. We also found that interspecific variation in CNDD, which might attenuate its stabilizing effect on species diversity14,15, was high but not significantly different across latitudes. Although the consequences of these patterns for latitudinal diversity gradients are difficult to evaluate, we speculate that a more effective regulation of population abundances could translate into greater stabilization of tropical tree communities and thus contribute to the high local diversity of tropical forests.


Asunto(s)
Biodiversidad , Bosques , Mapeo Geográfico , Árboles , Modelos Biológicos , Especificidad de la Especie , Árboles/clasificación , Árboles/fisiología , Clima Tropical
2.
J Drugs Dermatol ; 23(5): 306-310, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38709694

RESUMEN

BACKGROUND: There are no guidelines on when to more strongly recommend sentinel lymph node biopsy (SLNB) for T1b melanomas. OBJECTIVE: To examine whether anatomic locations of T1b melanomas and patient age influence metastases. METHODS: We conducted a retrospective study using data from two hospitals in Los Angeles County from January 2010 through January 2020. RESULTS: Out of 620 patients with primary melanomas, 566 melanomas were staged based on the American Joint Committee on Cancer 8th edition melanoma staging. Forty-one were T1b, of which 13 were located on the face/ear/scalp and 28 were located elsewhere. T1b melanomas located on the face/ear/scalp had an increased risk of lymph node or distant metastasis compared with other anatomic sites (31% vs 3.6%, P=0.028). For all melanomas, the risk of lymph node or distant metastasis decreased with age of 64 years or greater (P<0.001 and P=0.034). For T1b melanomas, the risk of distant metastasis increased with increasing age (P=0.047). LIMITATIONS: Data were from a single county.  Conclusion: T1b melanomas of the face/ear/scalp demonstrated a higher risk of lymph node or distant metastasis and may help guide the recommendation of SLNB, imaging, and surveillance. Younger patients may be more strongly considered for SLNB and older patients with T1b melanomas may warrant imaging.  J Drugs Dermatol. 2024;23(5):306-310. doi:10.36849/JDD.7667.


Asunto(s)
Metástasis Linfática , Melanoma , Estadificación de Neoplasias , Biopsia del Ganglio Linfático Centinela , Neoplasias Cutáneas , Humanos , Melanoma/patología , Melanoma/diagnóstico , Melanoma/epidemiología , Estudios Retrospectivos , Femenino , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/epidemiología , Masculino , Persona de Mediana Edad , Anciano , Factores de Edad , Metástasis Linfática/diagnóstico , Adulto , Anciano de 80 o más Años , Los Angeles/epidemiología , Adulto Joven
3.
Neurosurg Focus ; 52(1): E15, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34973668

RESUMEN

OBJECTIVE: The utility of robotic instrumentation is expanding in neurosurgery. Despite this, successful examples of robotic implementation for endoscopic endonasal or skull base neurosurgery remain limited. Therefore, the authors performed a systematic review of the literature to identify all articles that used robotic systems to access the sella or anterior, middle, or posterior cranial fossae. METHODS: A systematic review of MEDLINE and PubMed in accordance with PRISMA guidelines performed for articles published between January 1, 1990, and August 1, 2021, was conducted to identify all robotic systems (autonomous, semiautonomous, or surgeon-controlled) used for skull base neurosurgical procedures. Cadaveric and human clinical studies were included. Studies with exclusively otorhinolaryngological applications or using robotic microscopes were excluded. RESULTS: A total of 561 studies were identified from the initial search, of which 22 were included following full-text review. Transoral robotic surgery (TORS) using the da Vinci Surgical System was the most widely reported system (4 studies) utilized for skull base and pituitary fossa procedures; additionally, it has been reported for resection of sellar masses in 4 patients. Seven cadaveric studies used the da Vinci Surgical System to access the skull base using alternative, non-TORS approaches (e.g., transnasal, transmaxillary, and supraorbital). Five cadaveric studies investigated alternative systems to access the skull base. Six studies investigated the use of robotic endoscope holders. Advantages to robotic applications in skull base neurosurgery included improved lighting and 3D visualization, replication of more traditional gesture-based movements, and the ability for dexterous movements ordinarily constrained by small operative corridors. Limitations included the size and angulation capacity of the robot, lack of drilling components preventing fully robotic procedures, and cost. Robotic endoscope holders may have been particularly advantageous when the use of a surgical assistant or second surgeon was limited. CONCLUSIONS: Robotic skull base neurosurgery has been growing in popularity and feasibility, but significant limitations remain. While robotic systems seem to have allowed for greater maneuverability and 3D visualization, their size and lack of neurosurgery-specific tools have continued to prevent widespread adoption into current practice. The next generation of robotic technologies should prioritize overcoming these limitations.


Asunto(s)
Neurocirugia , Procedimientos Quirúrgicos Robotizados , Robótica , Humanos , Procedimientos Neuroquirúrgicos , Procedimientos Quirúrgicos Robotizados/métodos , Base del Cráneo/cirugía
4.
Am J Otolaryngol ; 43(6): 103558, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36029622

RESUMEN

PURPOSE: This study aims to elucidate any relationship between prior tonsillectomy and the presence of oropharyngeal HPV DNA found in screening mouth rinses. MATERIALS AND METHODS: A cross sectional study was conducted using the 2011-2014 National Health and Nutrition Examination Survey (NHANES). Participants between 40 and 69 were included in the study and medical, surgical, and sexual health history were recorded. Multivariable analyses were conducted to examine factors associated with HPV prevalence in oral rinse samples. RESULTS: A total of 4825 participants were recorded with 21.1 % having a history of tonsillectomy. In the no tonsillectomy group, 8.6 % of respondents had a positive oral rinse for HPV, while 7.2 % of those with a tonsillectomy had a positive rinse sample. There was no association between age and HPV prevalence (OR = 1.04, 95 % CI: [1.00-1.07]). When controlling for demographics, medical history, and sexual behaviors, tonsillectomy history was not shown to have an association with HPV (OR = 0.86, 95 % CI: [0.53-1.40]). However, men, Hispanics, smokers, and those with higher lifetime sexual partners had increased odds of having a positive HPV oral rinse sample which was statistically significant. CONCLUSION: Our data showed that a history of tonsillectomy was not significantly associated with the presence of HPV in an oral rinse. However, a significant relationship was seen between the presence of HPV in oral rinses and certain demographic factors such as male gender, Hispanic race, smoking history, and increased sexual partners.


Asunto(s)
Alphapapillomavirus , Infecciones por Papillomavirus , Adulto , Masculino , Humanos , Papillomaviridae/genética , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/complicaciones , Encuestas Nutricionales , Antisépticos Bucales , Estudios Transversales , Factores de Riesgo , Prevalencia
5.
J Head Trauma Rehabil ; 36(4): 264-273, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33656474

RESUMEN

OBJECTIVE: The main objective of this study was to assess whether objective vestibular, oculomotor, and balance functions were impaired in children with a current diagnosis of concussion with vestibular and/or ocular symptoms. SETTING: Data were collected in a vestibular/ocular clinical laboratory. Patient participants were recruited from a concussion clinic in a children's hospital. PARTICIPANTS: Thirty-three children aged 8 to 17 years with a current diagnosis of concussion and vestibular and/or ocular symptoms and 30 children without concussion. DESIGN: Cross-sectional single-visit study. MAIN OUTCOME MEASURES: Eye-tracking rotary chair oculomotor and vestibular measures, vestibular evoked potentials, and static posturography. RESULTS: There were no statistically significant differences on any clinical measure between children with concussion and children without concussion. Younger children without concussion performed significantly worse on several rotary chair and balance measures compared with older children without concussion. CONCLUSIONS: No vestibular, oculomotor, or balance measures were significantly different between children with concussion and children without concussion, suggesting these measures may not be useful in the evaluation of a child with concussion and vestibular and/or oculomotor symptoms. Future research should investigate age effects and other vestibular and oculomotor tests to identify objective findings that better relate to vestibular and/or ocular symptoms in children with concussion.


Asunto(s)
Traumatismos en Atletas , Conmoción Encefálica , Adolescente , Conmoción Encefálica/diagnóstico , Niño , Estudios Transversales , Movimientos Oculares , Humanos , Equilibrio Postural
6.
Optom Vis Sci ; 98(7): 764-770, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34328455

RESUMEN

SIGNIFICANCE: Pre-participation physical evaluation and its vision screenings have been the mainstay of medical clearance for competitive play for decades. The ability of screening to address athlete's sports-specific vision needs is unknown. METHODS: Fifty-eight intercollegiate football players consented to participate in a comprehensive, sports-specific eye examination in addition to the standard pre-participation vision screening. Sensitivity, specificity, and positive and negative predictive values were determined for screening's ability to detect athletes whose vision might improve with correction, athletes who had significant ocular findings that impact safety, and either of the two conditions together. The effect no recent eye examination added to pre-participation vision screening results was evaluated for change in screening yield. Descriptive statistics of the cohort and associations with no recent comprehensive eye examination were generated. RESULTS: The pre-participation vision screening was able to identify three athletes not meeting visual acuity requirements for medical clearance to play without a comprehensive assessment. A failed screening was poorly able to identify athletes who might benefit from improved acuity (sensitivity, 9.1%; specificity, 100%), have sports-specific significant ocular findings (sensitivity, 10.5%; specificity, 97.3%), or have either together (sensitivity, 7.5%; specificity, 100%). Sixty percent (33/55) of athletes reported never having a comprehensive examination or one within the last 10 years. Fifty-eight percent (34/58) had improved best-corrected visual acuity after comprehensive examination, and 81% (47/58) had improved acuity or a sports-specific significant finding. CONCLUSIONS: The pre-participation vision screening was largely able to identify athletes meeting the minimum visual acuity requirement for athlete clearance. It poorly identified those who might benefit from improved vision with refractive correction and those in whom sport-specific significant eye findings were noted. Comprehensive eye care had a clear benefit for the majority of athletes tested. This benefit needs to be balanced with the potential added costs and time constraints to players and athletic department staff.


Asunto(s)
Deportes , Selección Visual , Atletas , Humanos , Estudiantes , Agudeza Visual
7.
Optom Vis Sci ; 98(7): 833-838, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34328460

RESUMEN

SIGNIFICANCE: Football helmet visors are popular among players and may increase safety. However, they may also be costly or impractical, or impair the evaluation of head and neck injury. Determining an objective list of vision-related clinical conditions may help meet risk-benefit ratios while increasing access to care to athletes with special needs. PURPOSE: The purpose of this study was to determine an objective list of vision-related conditions that may benefit from clear and tinted football helmet visor use in athletes. METHODS: After comprehensive dilated eye examinations on 58 Division I collegiate football players at the University of Alabama at Birmingham between February 2017 and June 2018, an expert panel in vision care, sports medicine, and football equipment convened to determine vision-related conditions most important for clear or tinted football helmet visor use. RESULTS: In August 2018, the list drafted by the expert vision and sports medical panel in which a clear football helmet visor might be justified included conditions associated with retinal detachment and unilateral or binocular vision loss as well as high refractive error, refractive surgery, corneal compromise, and other conditions, which would necessitate additional eye protection. Of the 58 players examined, 3 (5%) were determined to have eye conditions that would require a clear visor as deemed by the expert panel, and 3 (5%) were determined to have eye conditions for which a clear visor was recommended. No players met indications for a tinted visor including congenital eye conditions that limit useful vision in daylight or bright-light environments, acquired conditions that may increase light sensitivity, and light-induced systemic conditions. CONCLUSIONS: This objective list of eye and vision-related systemic conditions is intended to mitigate the risk of long-term eye damage and/or vision deprivation. Clear and especially tinted football helmet visors require the sports medicine team to evaluate factors that will maximize the vision, head, and neck health of the athlete while increasing accessibility to sports for individuals with unique abilities.


Asunto(s)
Fútbol Americano , Dispositivos de Protección de la Cabeza , Atletas , Humanos
8.
Dysphagia ; 36(6): 1040-1047, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33386998

RESUMEN

The purpose of this study is to analyze outcomes of combined antegrade-retrograde dilations (CARD). This retrospective study was conducted on 14 patients with a history of head and neck cancer, treated with radiation therapy that was complicated by either complete or near-complete esophageal stenosis. All patients had minimal oral intake and depended on a gastrostomy tube for nutrition. Swallow function before and after CARD was assessed using the Functional Oral Intake Scale, originally developed for stroke patients and applied to head and neck cancer patients. Patients undergoing CARD demonstrated a quantifiable improvement in swallow function (p = 0.007) that persisted at last known follow-up (p = 0.015) but only a minority (23.1%) achieved oral intake sufficient to obviate the need for tube feeds. Complication rates were 24% per procedure or 36% per patient, almost all complications required procedural intervention, and all complications occurred in patients with complete stenosis. Our study suggests further caution when considering CARD, careful patient selection, and close post-operative monitoring.


Asunto(s)
Trastornos de Deglución , Estenosis Esofágica , Neoplasias de Cabeza y Cuello , Trastornos de Deglución/etiología , Dilatación , Estenosis Esofágica/etiología , Estenosis Esofágica/terapia , Neoplasias de Cabeza y Cuello/complicaciones , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
9.
Oral Dis ; 26(5): 930-940, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32011771

RESUMEN

OBJECTIVES: To investigate the differences in oral HPV infection and sexual behaviors by race in the US. MATERIALS AND METHODS: We analyzed data from the 2011-2014 US National Health and Nutrition Examination Survey during which participants aged 18-69 years completed oral rinse exam for HPV detection (n = 8,229). Logistic regression was used to examine the associations of race with various types of oral HPV infection and sexual behaviors. RESULTS: The prevalence of overall oral HPV infection and HPV type16 infection was 7.5% [95% CI: 6.6-8.4] and 1.1% [95% CI: 0.7-1.3], respectively. Blacks were more likely to have any oral HPV infection [OR: 1.22, 95% CI: 1.01-1.47] and Asian Americans were less likely to have any oral HPV infection [OR: 0.33, 95% CI: 0.24-0.49] than Whites. In a multivariate model, Whites were less likely to have any oral HPV infections than Blacks while having higher order of impact by the number of lifetime sex partners. Overall, Asian Americans were less likely to have type16 infection [OR: 0.21, 95% CI: 0.06-0.67] than Whites; however, that difference disappears when adjusting for sexual behaviors. CONCLUSIONS: In this nationally representative sample of US adults, the prevalence of overall oral HPV infections was higher among Blacks and lower among Asians in comparison to Whites. Further analysis with sexual behavior data suggested that the racial differences in prevalence are likely due to different sexual behaviors.


Asunto(s)
Papillomaviridae , Infecciones por Papillomavirus , Conducta Sexual , Adolescente , Adulto , Anciano , Asiático , Población Negra , Humanos , Persona de Mediana Edad , Encuestas Nutricionales , Infecciones por Papillomavirus/epidemiología , Prevalencia , Factores de Riesgo , Parejas Sexuales , Estados Unidos/epidemiología , Población Blanca , Adulto Joven
10.
Optom Vis Sci ; 97(11): 917-928, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33136709

RESUMEN

SIGNIFICANCE: Vision problems occur at higher rates in children with autism spectrum disorder (ASD) than in the general population. Some professional organizations recommend that children with neurodevelopmental disorders need comprehensive assessment by eye care professionals rather than vision screening. METHODS: Data from the 2011 to 2012 National Survey of Children's Health (NSCH) were accessed. Logistic regression was used to evaluate differences between vision screening rates in eye care professionals' offices and other screening locations among children with and without ASD. RESULTS: Overall, 82.21% (95% confidence interval [CI], 78.35 to 86.06%) of children with ASD were reported to have had a vision screening as defined by the NSCH criteria. Among children younger than 5 years with ASD, 8.87% (95% CI, 1.27 to 16.5%) had a vision screening at a pediatrician's office, 41.1% (95% CI, 20.54 to 61.70%) were screened at school, and 37.62% (95% CI, 9.80 to 55.45%) were examined by an eye care professionals. Among children with ASD older than 5 years, 24.84% (95% CI, 18.42 to 31.26%) were screened at school, 22.24% (95% CI, 17.26 to 27.21%) were screened at the pediatricians' office, and 50.15% (95% CI, 44.22 to 56.08%) were examined by eye care professionals. Based on estimates from NSCH, no children in the U.S. population younger than 5 years with ASD screened in a pediatrician's office were also seen by an eye care provider. CONCLUSIONS: If the public health goal is to have all children with ASD assessed in an eye care professional's office, data from the NSCH indicate that we as a nation are falling far short of that target.


Asunto(s)
Trastorno del Espectro Autista/diagnóstico , Trastornos de la Visión/diagnóstico , Selección Visual , Adolescente , Niño , Salud Infantil , Preescolar , Femenino , Humanos , Lactante , Modelos Logísticos , Masculino , Prevalencia
11.
Proc Biol Sci ; 286(1902): 20190672, 2019 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-31064307

RESUMEN

Understanding the number of times a trait has evolved is a necessary foundation for comprehending its potential relationships with selective regimes, developmental constraints and evolutionary diversification. Rodents make up over 40% of extant mammalian species, and their ecological and evolutionary success has been partially attributed to the increase in biting efficiency that resulted from a forward shift of one or two portions of the masseter muscle from the zygomatic arch onto the rostrum. This forward shift has occurred in three discrete ways, but the number of times it has occurred has never been explicitly quantified. We estimated an ultrametric phylogeny, the first to include all rodent families, using thousands of ultraconserved elements. We examined support for evolutionary relationships among the five rodent suborders and then incorporated relevant fossils, fitted models of character evolution, and used stochastic character mapping to determine that a portion of the masseter muscle has moved forward onto the rostrum at least seven times (with one reversal) during the approximately 70 Myr history of rodents. Combined, the repeated evolution of this key innovation, its increasing prevalence through time, and the species diversity of clades with this character underscores the adaptive value of improved biting efficiency and the relative ease with which some advantageous traits arise.


Asunto(s)
Evolución Biológica , Músculo Masetero/anatomía & histología , Roedores/anatomía & histología , Animales , Filogenia , Roedores/clasificación
12.
Glob Chang Biol ; 25(11): 3985-3994, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31148284

RESUMEN

Wildfire is an essential earth-system process, impacting ecosystem processes and the carbon cycle. Forest fires are becoming more frequent and severe, yet gaps exist in the modeling of fire on vegetation and carbon dynamics. Strategies for reducing carbon dioxide (CO2 ) emissions from wildfires include increasing tree harvest, largely based on the public assumption that fires burn live forests to the ground, despite observations indicating that less than 5% of mature tree biomass is actually consumed. This misconception is also reflected though excessive combustion of live trees in models. Here, we show that regional emissions estimates using widely implemented combustion coefficients are 59%-83% higher than emissions based on field observations. Using unique field datasets from before and after wildfires and an improved ecosystem model, we provide strong evidence that these large overestimates can be reduced by using realistic biomass combustion factors and by accurately quantifying biomass in standing dead trees that decompose over decades to centuries after fire ("snags"). Most model development focuses on area burned; our results reveal that accurately representing combustion is also essential for quantifying fire impacts on ecosystems. Using our improvements, we find that western US forest fires have emitted 851 ± 228 Tg CO2 (~half of alternative estimates) over the last 17 years, which is minor compared to 16,200 Tg CO2 from fossil fuels across the region.


Asunto(s)
Incendios , Incendios Forestales , Ecosistema , Bosques , Árboles
13.
J Neurol Phys Ther ; 43(3): 153-159, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31205229

RESUMEN

BACKGROUND AND PURPOSE: According to the most recent consensus statement on management of sport-related concussion (SRC), athletes with suspected SRC should receive a comprehensive neurological examination. However, which measures to include in such an examination are not defined. Our objectives were to (1) evaluate test-retest reliability and normative data on vestibular and balance tests in athletes without SRC; (2) compare athletes with and without SRC on the subtests; and (3) identify subtests for concussion testing protocols. METHODS: Healthy athletes (n = 87, mean age 20.6 years; standard deviation = 1.8 years; 39 female and 48 male) and athletes with SRC (n = 28, mean age 20.7 years; standard deviation = 1.9 years; 11 female and 17 male) were tested using rotary chair, cervical vestibular-evoked myogenic potential (c-VEMP), and the Sensory Organization Test (SOT). A subset (n = 43) were tested twice. We analyzed reliability of the tests, and compared results between athletes with and without SRC. RESULTS: Reliability ranged from poor to strong. There was no significant difference between athletes with and without SRC for tests of peripheral vestibular function (ie, rotary chair and c-VEMP). Athletes with SRC had significantly worse scores (P < 0.05) on vestibular-ocular reflex (VOR) cancellation gain, subjective visual vertical and horizontal variance, and all conditions of the SOT. DISCUSSION AND CONCLUSION: SRC did not affect medium frequency VOR or saccular function. SRC did affect the ability to use vestibular inputs for perception of vertical and postural control, as well as ability to cancel the VOR.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A274).


Asunto(s)
Traumatismos en Atletas/fisiopatología , Conmoción Encefálica/fisiopatología , Equilibrio Postural/fisiología , Vestíbulo del Laberinto/fisiopatología , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Examen Neurológico , Reflejo Vestibuloocular/fisiología , Reproducibilidad de los Resultados , Adulto Joven
14.
Optom Vis Sci ; 96(4): 256-265, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30907863

RESUMEN

SIGNIFICANCE: Oculomotor tests in concussion commonly show impairment in smooth pursuit and saccadic function. Honing in on the systems likely to be affected by concussion will streamline use of oculomotor function as a supplemental diagnostic and prognostic tool, as well as improve our understanding of the pathophysiology of concussion. PURPOSE: This study investigates oculomotor function between concussed and healthy collegiate athletes and determines measurement test-retest reliability of those tools. METHODS: Eighty-seven healthy athletes were recruited from a U.S. Division 1 sports university and completed a 30-minute vestibular ocular testing battery in an enclosed rotary chair system equipped with 100-Hz eye-tracking goggles. Forty-three individuals completed the battery twice. Twenty-eight individuals with a current diagnosis of concussion also completed the battery. All participants were aged 18 to 24 years. Bivariate statistical tests examined differences in scores across groups, and intraclass coefficients were computed to test reliability. RESULTS: Concussed individuals had significantly longer saccadic, visual, and dual-task reaction times and reduced saccadic accuracy. There was no difference in optokinetic reflex gain, but few concussed individuals tolerated the task. Reaction time latencies and optokinetic gain show moderate test-retest reliability. Smooth pursuit tasks and saccadic accuracies showed poor test-retest reliability. CONCLUSIONS: Saccadic latency was the most sensitive oculomotor function to change after concussion and was reliable over time. Saccadic accuracy was significantly lower in the concussed group but had poor retest reliability. Optokinetic gain may warrant more investigation because of its high test-retest reliability and symptom provocation in concussion, despite not showing a significant difference between groups.


Asunto(s)
Traumatismos en Atletas/fisiopatología , Conmoción Encefálica/fisiopatología , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Adolescente , Atletas , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Seguimiento Ocular Uniforme/fisiología , Reproducibilidad de los Resultados , Movimientos Sacádicos/fisiología , Pruebas de Función Vestibular , Adulto Joven
15.
Optom Vis Sci ; 94(1): 89-95, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27464573

RESUMEN

PURPOSE: The King-Devick test (KD) has been studied as a remove-from-play sideline test in college-age athletes and older; however, studies in younger athletes are limited. A cross-sectional study of the KD and other vision correlates was completed on school-aged athletes during pre-season physicals for a variety of sports to determine the repeatability of the KD. The study also evaluated how convergence, alignment, or pupil function contributed to a slower King-Devick baseline reading. METHODS: Seven hundred eighty-five athletes underwent vision screenings in a hospital or school setting by trained/certified staff as part of pre-season physicals. Six hundred nineteen had KD testing completed per the manufacturer's suggested protocol and repeated. Other baseline vision testing included visual acuity, Modified Thorington testing for alignment, convergence testing, and pupil function using the NeurOptics (NPI-200) NPi. RESULTS: The mean fastest, error-minimized KD time for all participants was 43.9 seconds(s) (SD ± 11.6, range 24-120). Median KD time got faster (+) with age (p < 0.0001). The inter-class correlation coefficient for all scores was 0.92. The absolute mean time difference for any two tests was 3.5 s (SD ± 2.5, range 0-23). There was no association between the best KD time and reduced NPC (p = 0.63), Modified Thorington measure of alignment (p = 0.55), or NPi pupil function (p = 0.79). The Bland Altman repeated measure limits of agreement was ±6.5 seconds for those in the 10th to12th grades, and ±10.2 seconds for those in the 6th to 9th grades. CONCLUSIONS: King-Devick score in junior high and high school athletes is variable but gets faster and more repeatable with increasing age. The KD does not correlate significantly with reduced convergence, alignment, or pupil function. Based on grouped data, a slowing of 10 seconds for younger athletes and 6 seconds for older athletes on a second administration represents a true difference in testing speed. Within-player variability should be considered when removal-from-play decisions are influenced by KD results.


Asunto(s)
Traumatismos en Atletas/diagnóstico , Conmoción Encefálica/diagnóstico , Convergencia Ocular/fisiología , Pupila/fisiología , Selección Visual/métodos , Agudeza Visual/fisiología , Adolescente , Atletas , Traumatismos en Atletas/fisiopatología , Conmoción Encefálica/fisiopatología , Estudios Transversales , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Estaciones del Año
16.
Optom Vis Sci ; 94(1): 60-67, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27668641

RESUMEN

PURPOSE: Academic difficulty is reported in children with prolonged post-concussive symptoms. Despite growing evidence that vestibular-ocular and vision-specific dysfunction are common in children after concussion, vision is rarely mentioned in return-to-learn protocols. The purpose of this project was to evaluate a cohort of children with prolonged post-concussive symptoms to determine if vision symptoms are associated with those reporting academic difficulty. METHODS: Data were obtained from the Children's of Alabama Concussion Clinic REDCap dataset from the period January 2007 to October 2013. From this dataset of 1033 concussion events, a cohort of 276 children aged 5 to 18 years with three or more concussion-related symptoms present for 10 days or more was identified. A cross-sectional cohort study was undertaken to evaluate the association of concussion symptoms, SCAT2 scores, and demographic and concussion severity markers to reported educational difficulty among children with prolonged post-concussive symptoms. Univariate and multivariate logistic regression techniques were used to model the association of reported educational difficulty to self-reported vision abnormalities. RESULTS: Mean age was 13.8 years. Median time since the concussive event was 21 days, with 33% (95/276) reporting their concussion more than 30 days before data collection. Academic difficulty was reported by 29% (79/270) and vision abnormalities in 46% (128/274). After model reduction, vision symptoms (OR 2.17, 95% CI 1.02, 4.62), hearing disturbance (OR 2.39, 95% CI 1.06, 5.36), and concentration difficulty (OR 21.62, 95% CI 9.50, 44.47) remained associated with academic difficulty. For those with symptoms 30 days or more after concussion, only vision (OR 3.15, 95% CI 1.06, 9.38) and concentration difficulty (OR 15.33, 95% CI 4.99, 47.05) remained statistically significant. CONCLUSIONS: Vision problems were commonly reported in children with concussions and were independently associated with those reporting academic difficulty. Comprehensive vision assessment should be considered in children reporting academic difficulty and in the development of return-to-learn protocols.


Asunto(s)
Conmoción Encefálica/complicaciones , Discapacidades para el Aprendizaje/etiología , Síndrome Posconmocional/etiología , Trastornos de la Visión/etiología , Adolescente , Niño , Preescolar , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Discapacidades para el Aprendizaje/diagnóstico , Masculino , Síndrome Posconmocional/diagnóstico , Autoinforme , Encuestas y Cuestionarios , Trastornos de la Visión/diagnóstico
17.
South Med J ; 110(7): 447-451, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28679012

RESUMEN

OBJECTIVES: In traditionally underserved communities, faith-based interventions have been shown to be effective for health promotion. Religious leaders-generally the major partner in such interventions-however, are seldom are consulted about community health priorities and health promotion preferences. These insights are critical to ensure productive partnerships, effective programming, and sustainability. METHODS: Mixed-methods surveys were administered in one of the nation's most under-resourced regions: rural Appalachia. A sample of 60 religious leaders, representing the main denominations in central Appalachia, participated. Measures included closed- and open-ended survey questions on health priorities and recommendations for health promotion. Descriptive statistics were used for closed-ended survey items and conventional qualitative content analysis was used for open-ended responses. RESULTS: Substance abuse, diabetes mellitus, suboptimal dietary intake and obesity/overweight, and cardiovascular and respiratory illnesses constitute major health concerns. Addressing these challenging conditions requires realistically acknowledging sparse community resources (particularly healthcare provider shortages); building in accountability; and leveraging local assets and traditions such as testimonials, intergenerational support, and witnessing. CONCLUSIONS: With their extensive reach within the community and their accurate understanding of community health threats, practitioners and researchers may find religious leaders to be natural allies in health-promotion and disease-prevention activities.


Asunto(s)
Enfermedad Crónica/prevención & control , Enfermedad Crónica/psicología , Clero/psicología , Prioridades en Salud , Promoción de la Salud , Religión y Medicina , Población Rural , Poblaciones Vulnerables , Anciano , Región de los Apalaches , Femenino , Conductas Relacionadas con la Salud , Encuestas de Atención de la Salud , Necesidades y Demandas de Servicios de Salud , Estilo de Vida Saludable , Humanos , Comunicación Interdisciplinaria , Colaboración Intersectorial , Kentucky , Masculino , Persona de Mediana Edad , Factores de Riesgo , Trastornos Relacionados con Sustancias/epidemiología , Encuestas y Cuestionarios
18.
Biochem J ; 466(3): 547-59, 2015 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-25437641

RESUMEN

In eukaryotes, amino acid deprivation leads to the accumulation of uncharged tRNAs that are detected by Gcn2 (general control non-derepressible 2), which in turn phosphorylates eIF2α (α-subunit of eukaryotic translation initiation factor 2), an essential process for overcoming starvation. In Saccharomyces cerevisiae, sensing amino acid shortages requires that Gcn2 binds directly to its effector protein Gcn1 and both must associate with the ribosome. Our hypothesis is that uncharged tRNAs occur in the ribosomal A-site and that Gcn1 is directly involved in transfer of this starvation signal to Gcn2. In the present paper, we provide evidence that Gcn1 directly contacts the small ribosomal protein S10 (Rps10). Gcn1 residues 1060-1777 showed a yeast two-hybrid (Y2H) interaction with Rps10A. In vitro, Rps10A or Rps10B co-precipitated Gcn1[1060-1777] in an RNA-independent manner. rps10AΔ or rps10BΔ strains showed reduced eIF2α phosphorylation under replete conditions and shortly after onset of starvation, suggesting that Gcn1-mediated Gcn2 activation was impaired. Overexpression of GST-tagged Rps10 reduced growth under amino acid starvation and this was exacerbated by the Gcn1-M7A mutation known to impair Gcn1-ribosome interaction and Gcn2 activity. Under amino acid starvation, eEF3 (eukaryotic translation elongation factor 3) overexpression, known to weaken Gcn1 function on the ribosome, exacerbated the growth defect of rps10AΔ or rps10BΔ strains. Taken together, these data support the idea that Gcn1 contacts ribosome-bound Rps10 to efficiently mediate Gcn2 activation.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Factores de Elongación de Péptidos/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Ribosómicas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Proteínas de Arabidopsis/genética , Activación Enzimática/fisiología , Técnicas de Silenciamiento del Gen , Factores de Elongación de Péptidos/genética , Proteínas Serina-Treonina Quinasas/genética , Proteínas Ribosómicas/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Schizosaccharomyces pombe/genética
19.
Optom Vis Sci ; 93(5): 459-65, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26855242

RESUMEN

PURPOSE: To compare the prevalence of attention deficit/hyperactivity disorder (ADHD) in children with normal vision and with vision problems not correctable with glasses or contact lenses (vision problems) as determined by parent report in a nationwide telephone survey. METHODS: This cross-sectional study included 75,171 children without intellectual impairment aged 4 to 17 years participating in the 2011 to 2012 National Survey of Children's Health, conducted by the U.S. Centers for Disease Control and Prevention. Demographic information and information regarding vision and ADHD status were obtained by parent interview. Questions asked whether they had ever been told by a doctor or health care provider that the child had a vision problem not correctable with glasses or contact lenses, ADHD, intellectual impairment, or one of 13 other common chronic conditions of childhood. A follow-up question asked about condition severity. The main outcome measure was current ADHD. RESULTS: The prevalence of current ADHD was greater (p < 0.0001) among children with vision problems (15.6%) compared with those with normal vision (8.3%). The odds of ADHD compared with those of children with normal vision were greatest for those with moderate vision problems (odds ratio [OR], 2.6; 95% confidence interval [95% CI], 1.7 to 4.4) and mild vision problems (OR, 1.8; 95% CI, 1.1 to 2.9). Children with severe vision problems had similar odds of ADHD to those of children with normal vision perhaps because of the small numbers in this group (OR, 1.6; 95% CI, 0.8 to 3.1). In multivariable analysis adjusting for confounding variables, vision problems remained independently associated with current ADHD (OR, 1.8; 95% CI, 1.2 to 2.7). CONCLUSIONS: In this large nationally representative sample, the prevalence of ADHD was greater among children with vision problems not correctable with glasses or contacts. The association between vision problems and ADHD remains even after adjusting for other factors known to be associated with ADHD.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/epidemiología , Trastornos de la Visión/epidemiología , Personas con Daño Visual/estadística & datos numéricos , Adolescente , Niño , Salud Infantil , Preescolar , Estudios Transversales , Femenino , Investigación sobre Servicios de Salud , Encuestas Epidemiológicas , Humanos , Masculino , Oportunidad Relativa , Prevalencia , Encuestas y Cuestionarios , Estados Unidos/epidemiología
20.
Ecology ; 96(11): 2855-61, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27070005

RESUMEN

Rates and spatial patterns of tree mortality are predicted to change during forest structural development. In young forests, mortality should be primarily density dependent due to competition for light, leading to an increasingly spatially uniform pattern of surviving trees. In contrast, mortality in old-growth forests should be primarily caused by contagious and spatially autocorrelated agents (e.g., insects, wind), causing spatial aggregation of surviving trees to increase through time. We tested these predictions by contrasting a three-decade record of tree mortality from replicated mapped permanent plots located in young (< 60-year-old) and old-growth (> 300-year-old) Abies amabilis forests. Trees in young forests died at a rate of 4.42% per year, whereas trees in old-growth forests died at 0.60% per year. Tree mortality in young forests was significantly aggregated, strongly density dependent, and caused live tree patterns to become more uniform through time. Mortality in old-growth forests was spatially aggregated, but was density independent and did not change the spatial pattern of surviving trees. These results extend current theory by demonstrating that density-dependent competitive mortality leading to increasingly uniform tree spacing in young forests ultimately transitions late in succession to a more diverse tree mortality regime that maintains spatial heterogeneity through time.


Asunto(s)
Abies/fisiología , Bosques , Longevidad/fisiología , Árboles/fisiología , Densidad de Población
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