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1.
N Engl J Med ; 390(9): 806-818, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38416429

RESUMEN

BACKGROUND: Cognitive symptoms after coronavirus disease 2019 (Covid-19), the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), are well-recognized. Whether objectively measurable cognitive deficits exist and how long they persist are unclear. METHODS: We invited 800,000 adults in a study in England to complete an online assessment of cognitive function. We estimated a global cognitive score across eight tasks. We hypothesized that participants with persistent symptoms (lasting ≥12 weeks) after infection onset would have objectively measurable global cognitive deficits and that impairments in executive functioning and memory would be observed in such participants, especially in those who reported recent poor memory or difficulty thinking or concentrating ("brain fog"). RESULTS: Of the 141,583 participants who started the online cognitive assessment, 112,964 completed it. In a multiple regression analysis, participants who had recovered from Covid-19 in whom symptoms had resolved in less than 4 weeks or at least 12 weeks had similar small deficits in global cognition as compared with those in the no-Covid-19 group, who had not been infected with SARS-CoV-2 or had unconfirmed infection (-0.23 SD [95% confidence interval {CI}, -0.33 to -0.13] and -0.24 SD [95% CI, -0.36 to -0.12], respectively); larger deficits as compared with the no-Covid-19 group were seen in participants with unresolved persistent symptoms (-0.42 SD; 95% CI, -0.53 to -0.31). Larger deficits were seen in participants who had SARS-CoV-2 infection during periods in which the original virus or the B.1.1.7 variant was predominant than in those infected with later variants (e.g., -0.17 SD for the B.1.1.7 variant vs. the B.1.1.529 variant; 95% CI, -0.20 to -0.13) and in participants who had been hospitalized than in those who had not been hospitalized (e.g., intensive care unit admission, -0.35 SD; 95% CI, -0.49 to -0.20). Results of the analyses were similar to those of propensity-score-matching analyses. In a comparison of the group that had unresolved persistent symptoms with the no-Covid-19 group, memory, reasoning, and executive function tasks were associated with the largest deficits (-0.33 to -0.20 SD); these tasks correlated weakly with recent symptoms, including poor memory and brain fog. No adverse events were reported. CONCLUSIONS: Participants with resolved persistent symptoms after Covid-19 had objectively measured cognitive function similar to that in participants with shorter-duration symptoms, although short-duration Covid-19 was still associated with small cognitive deficits after recovery. Longer-term persistence of cognitive deficits and any clinical implications remain uncertain. (Funded by the National Institute for Health and Care Research and others.).


Asunto(s)
COVID-19 , Disfunción Cognitiva , Trastornos de la Memoria , Adulto , Humanos , Cognición , Disfunción Cognitiva/etiología , COVID-19/complicaciones , Trastornos de la Memoria/etiología , SARS-CoV-2 , Memoria , Inglaterra , Síndrome Post Agudo de COVID-19/etiología
2.
Proc Natl Acad Sci U S A ; 121(17): e2400086121, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38621132

RESUMEN

Vision can provide useful cues about the geometric properties of an object, like its size, distance, pose, and shape. But how the brain merges these properties into a complete sensory representation of a three-dimensional object is poorly understood. To address this gap, we investigated a visual illusion in which humans misperceive the shape of an object due to a small change in one eye's retinal image. We first show that this illusion affects percepts of a highly familiar object under completely natural viewing conditions. Specifically, people perceived their own rectangular mobile phone to have a trapezoidal shape. We then investigate the perceptual underpinnings of this illusion by asking people to report both the perceived shape and pose of controlled stimuli. Our results suggest that the shape illusion results from distorted cues to object pose. In addition to yielding insights into object perception, this work informs our understanding of how the brain combines information from multiple visual cues in natural settings. The shape illusion can occur when people wear everyday prescription spectacles; thus, these findings also provide insight into the cue combination challenges that some spectacle wearers experience on a regular basis.


Asunto(s)
Ilusiones , Humanos , Encéfalo , Señales (Psicología)
3.
PLoS Comput Biol ; 20(1): e1011783, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38206969

RESUMEN

Neurons throughout the brain modulate their firing rate lawfully in response to sensory input. Theories of neural computation posit that these modulations reflect the outcome of a constrained optimization in which neurons aim to robustly and efficiently represent sensory information. Our understanding of how this optimization varies across different areas in the brain, however, is still in its infancy. Here, we show that neural sensory responses transform along the dorsal stream of the visual system in a manner consistent with a transition from optimizing for information preservation towards optimizing for perceptual discrimination. Focusing on the representation of binocular disparities-the slight differences in the retinal images of the two eyes-we re-analyze measurements characterizing neuronal tuning curves in brain areas V1, V2, and MT (middle temporal) in the macaque monkey. We compare these to measurements of the statistics of binocular disparity typically encountered during natural behaviors using a Fisher Information framework. The differences in tuning curve characteristics across areas are consistent with a shift in optimization goals: V1 and V2 population-level responses are more consistent with maximizing the information encoded about naturally occurring binocular disparities, while MT responses shift towards maximizing the ability to support disparity discrimination. We find that a change towards tuning curves preferring larger disparities is a key driver of this shift. These results provide new insight into previously-identified differences between disparity-selective areas of cortex and suggest these differences play an important role in supporting visually-guided behavior. Our findings emphasize the need to consider not just information preservation and neural resources, but also relevance to behavior, when assessing the optimality of neural codes.


Asunto(s)
Corteza Visual , Animales , Corteza Visual/fisiología , Macaca , Disparidad Visual , Encéfalo , Neuronas/fisiología , Estimulación Luminosa/métodos
4.
Optom Vis Sci ; 101(5): 252-262, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38857038

RESUMEN

PURPOSE: We aimed to develop a paradigm that can efficiently characterize motion percepts in people with low vision and compare their responses with well-known misperceptions made by people with typical vision when targets are hard to see. METHODS: We recruited a small cohort of individuals with reduced acuity and contrast sensitivity (n = 5) as well as a comparison cohort with typical vision (n = 5) to complete a psychophysical study. Study participants were asked to judge the motion direction of a tilted rhombus that was either high or low contrast. In a series of trials, the rhombus oscillated vertically, horizontally, or diagonally. Participants indicated the perceived motion direction using a number wheel with 12 possible directions, and statistical tests were used to examine response biases. RESULTS: All participants with typical vision showed systematic misperceptions well predicted by a Bayesian inference model. Specifically, their perception of vertical or horizontal motion was biased toward directions orthogonal to the long axis of the rhombus. They had larger biases for hard-to-see (low contrast) stimuli. Two participants with low vision had a similar bias, but with no difference between high- and low-contrast stimuli. The other participants with low vision were unbiased in their percepts or biased in the opposite direction. CONCLUSIONS: Our results suggest that some people with low vision may misperceive motion in a systematic way similar to people with typical vision. However, we observed large individual differences. Future work will aim to uncover reasons for such differences and identify aspects of vision that predict susceptibility.


Asunto(s)
Sensibilidad de Contraste , Percepción de Movimiento , Baja Visión , Humanos , Percepción de Movimiento/fisiología , Masculino , Femenino , Adulto , Baja Visión/fisiopatología , Sensibilidad de Contraste/fisiología , Agudeza Visual/fisiología , Persona de Mediana Edad , Psicofísica , Adulto Joven , Teorema de Bayes , Estimulación Luminosa/métodos
5.
Pediatr Neurosurg ; 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38684141

RESUMEN

INTRODUCTION: At our institution, revascularization after indirect moyamoya surgery is routinely evaluated using magnetic resonance angiography (MRA) rather than catheter angiography. This study reviews how revascularization can be visualized on axial MRA versus catheter angiography and compares clinical outcomes of surgeries evaluated by routine postoperative MRA versus routine catheter angiography. METHODS: We reviewed the records of all patients treated at our institution who underwent unilateral encephaloduroarteriosynangiosis (EDAS)/pial synangiosis 2004-2021 at 1-21 years of age. Inclusion criteria included undergoing preoperative MRA within 18 months of surgery and postoperative MRA 3 to 30 months after surgery. Clinical outcome measures included postoperative stroke and transient ischemic attacks (TIAs), changes in symptoms (improved, unchanged, worsened), and new postoperative symptoms. Measures were compared between surgeries evaluated by routine postoperative MRA versus routine postoperative angiograms. For each surgery, we determined the ratios of the diameters and areas of the donor and contralateral corresponding vessels and the relative signal intensities of these two vessels on preoperative- and 3-to-30-month postoperative MRA. We did the same for the middle meningeal artery (MMA) ipsilateral to the donor artery and the contralateral MMA. We assessed changes from pre- to post-operation in diameter ratios, area ratios, relative signal intensity, ivy sign, and brain perfusion on arterial spin labeled (ASL) imaging. MRI and MRA measures of revascularization and flow were compared to Matsushima grades in patients who had postoperative catheter angiograms. RESULTS: Fifty-one operations were included. There were no significant differences in rates of strokes, TIAs, changes or new symptoms after surgeries evaluated by routine postoperative MRA versus catheter angiogram. Significant associations existed between greater collateralization on postoperative MRA and greater median increases in preoperative-to-postoperative ratios of donor-vessel-over-contralateral-vessel diameter (p=0.0461) and ipsilateral-MMA-over-contralateral-MMA diameter (p=0.0135). The median increase in the ratio of the donor-vessel-over-corresponding-contralateral-vessel diameters was significantly higher for Matsushima grade A versus B (p=0.036). The median increase in the ratio of the sum of donor-and-ipsilateral-MMA diameters over the sum of the contralateral vessel diameters was significantly higher for improved-versus-unchanged perfusion on ASL imaging (p=0.0074). There was a nonsignificant association between greater postoperative collateralization on MRA and Matsushima grade (p=0.1160) Conclusion: Cerebral revascularization after EDAS/pial synangiosis can be evaluated on axial MRA by comparing the diameter and/or signal intensity of the donor vessel and ipsilateral MMA to those of the corresponding contralateral vessels on postoperative-versus-preoperative MRA. The use of routine postoperative MRA rather than catheter angiography does not appear to negatively affect outcomes.

6.
Pediatr Surg Int ; 40(1): 76, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38466447

RESUMEN

BACKGROUND: Pneumatosis intestinalis (PI, presence of air in bowel wall) develops in a variety of settings and due to a variety of insults which is then characterized by varying severity and clinical course. Anecdotally, many of these cases are benign with few clinical sequelae; however, we lack evidence-based guidelines to help guide management of such lower-risk cases. We aimed to describe the clinical entity of low-risk PI, characterize the population of children who develop this form of PI, determine if management approach or clinical outcomes differed depending on the managing physician's field of practice, and finally determine if a shortened course of NPO and antibiotics was safe in the population of children with low-risk PI. METHODS: We performed a retrospective review of all children over age 1 year treated at Children's Hospital Colorado (CHCO), between 2009 and 2019 with a diagnosis of PI who did not also have a diagnosis of cancer or history of bone marrow transplant (BMT). Data including demographic variables, clinical course, and outcomes were obtained from the electronic medical record. Low-risk criteria included no need for ICU admission, vasopressor use, or urgent surgical intervention. RESULTS: Ninety-one children were treated for their first episode of PI during the study period, 72 of whom met our low-risk criteria. Among the low-risk group, rates of complications including hemodynamic decompensation during treatment, PI recurrence, Clostridium difficile colitis, and death did not differ between those who received 3 days or less of antibiotics and those who received more than 3 days of antibiotics. Outcomes also did not differ between children cared for by surgeons or pediatricians. CONCLUSIONS: Here, we define low-risk PI as that which occurs in children over age 1 who do not have a prior diagnosis of cancer or prior BMT and who do not require ICU admission, vasopressor administration, or urgent surgical intervention. It is likely safe to treat these children with only 3 days of antibiotic therapy and NPO. LEVEL OF EVIDENCE: Level III.


Asunto(s)
Neoplasias , Neumatosis Cistoide Intestinal , Niño , Humanos , Lactante , Estudios Retrospectivos , Factores de Riesgo , Progresión de la Enfermedad , Neoplasias/complicaciones , Antibacterianos/uso terapéutico , Neumatosis Cistoide Intestinal/diagnóstico , Neumatosis Cistoide Intestinal/cirugía
7.
Pediatr Surg Int ; 40(1): 169, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38954056

RESUMEN

PURPOSE: To present the functional results after a transanal proximal rectosigmoidectomy in patients with severe idiopathic constipation in which medical treatment has failed. METHODS: Patients with severe idiopathic constipation who underwent transanal proximal rectosigmoidectomy (TPRS) at Children's Hospital Colorado between June 2019 and March 2024 were included in the study. We compared multiple pre- and post-operative outcome measures and the patient's bowel regimen before and after resection. RESULTS: Fourteen patients underwent TPRS, 10 of whom were male. The average age at the time of surgery was 10.1 years (range 5-19). Seven patients have moderate to severe autism. Constipation-related clinic visits, family calls, procedural intervention, emergency room visits, and hospitalizations notably decreased frequency after TPRS. Laxative dosages and enema volume requirements were also reduced after surgery. Before surgery, all the patients suffered from daily fecal accidents, while post-operatively, all were completely free of stool accidents. CONCLUSION: In our experience, for patients who suffer from severe medically refractory idiopathic constipation, TPRS has provided improvement in their symptoms and decreased the complications inherent to this chronic disease. Parents and patients attest to a profound positive transformation in their quality of life after surgery.


Asunto(s)
Colon Sigmoide , Estreñimiento , Recto , Humanos , Estreñimiento/cirugía , Estreñimiento/etiología , Masculino , Femenino , Niño , Adolescente , Preescolar , Recto/cirugía , Colon Sigmoide/cirugía , Adulto Joven , Resultado del Tratamiento , Estudios Retrospectivos , Calidad de Vida
8.
J Cogn Neurosci ; 35(4): 736-748, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36724396

RESUMEN

Successful goal-directed actions require constant fine-tuning of the motor system. This fine-tuning is thought to rely on an implicit adaptation process that is driven by sensory prediction errors (e.g., where you see your hand after reaching vs. where you expected it to be). Individuals with low vision experience challenges with visuomotor control, but whether low vision disrupts motor adaptation is unknown. To explore this question, we assessed individuals with low vision and matched controls with normal vision on a visuomotor task designed to isolate implicit adaptation. We found that low vision was associated with attenuated implicit adaptation only for small visual errors, but not for large visual errors. This result highlights important constraints underlying how low-fidelity visual information is processed by the sensorimotor system to enable successful implicit adaptation.


Asunto(s)
Baja Visión , Humanos , Mano
9.
Cogn Affect Behav Neurosci ; 23(2): 248-275, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36539558

RESUMEN

Individuals engage in the process of risk-based decision making on a daily basis to navigate various aspects of life. There are, however, individual differences in this form of decision making, with some individuals exhibiting preference for riskier choices (risk taking) and others exhibiting preference for safer choices (risk aversion). Recent work has shown that extremes in risk taking (e.g., excessive risk taking or risk aversion) are not only cognitive features of neuropsychiatric diseases, but may in fact predispose individuals to the development of such diseases. To better understand individual differences in risk taking, and thus the mechanisms by which they confer disease vulnerability, the current study investigated the cognitive contributions to risk taking in both males and females. Rats were first behaviorally characterized in a decision-making task involving risk of footshock punishment and then tested on a battery of cognitive behavioral assays. Individual variability in risk taking was compared with performance on these tasks. Consistent with prior work, females were more risk averse than males. With the exception of the Set-shifting Task, there were no sex differences in performance on other cognitive assays. There were, however, sex-dependent associations between risk taking and specific cognitive measures. Greater risk taking was associated with better cognitive flexibility in males whereas greater risk aversion was associated with better working memory in females. Collectively, these findings reveal that distinct cognitive mechanisms are associated with risk taking in males and females, which may account for sex differences in this form of decision making.


Asunto(s)
Toma de Decisiones , Castigo , Ratas , Masculino , Femenino , Animales , Asunción de Riesgos , Cognición
10.
J Virol ; 96(17): e0097622, 2022 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-35938870

RESUMEN

Humoral immune perturbations contribute to pathogenic outcomes in persons with HIV-1 infection (PWH). Gut barrier dysfunction in PWH is associated with microbial translocation and alterations in microbial communities (dysbiosis), and IgA, the most abundant immunoglobulin (Ig) isotype in the gut, is involved in gut homeostasis by interacting with the microbiome. We determined the impact of HIV-1 infection on the antibody repertoire in the gastrointestinal tract by comparing Ig gene utilization and somatic hypermutation (SHM) in colon biopsies from PWH (n = 19) versus age and sex-matched controls (n = 13). We correlated these Ig parameters with clinical, immunological, microbiome and virological data. Gene signatures of enhanced B cell activation were accompanied by skewed frequencies of multiple Ig Variable genes in PWH. PWH showed decreased frequencies of SHM in IgA and possibly IgG, with a substantial loss of highly mutated IgA sequences. The decline in IgA SHM in PWH correlated with gut CD4+ T cell loss and inversely correlated with mucosal inflammation and microbial translocation. Diminished gut IgA SHM in PWH was driven by transversion mutations at A or T deoxynucleotides, suggesting a defect not at the AID/APOBEC3 deamination step but at later stages of IgA SHM. These results expand our understanding of humoral immune perturbations in PWH that could have important implications in understanding mucosal immune defects in individuals with chronic HIV-1 infection. IMPORTANCE The gut is a major site of early HIV-1 replication and pathogenesis. Extensive CD4+ T cell depletion in this compartment results in a compromised epithelial barrier that facilitates the translocation of microbes into the underlying lamina propria and systemic circulation, resulting in chronic immune activation. To date, the consequences of microbial translocation on the mucosal humoral immune response (or vice versa) remains poorly integrated into the panoply of mucosal immune defects in PWH. We utilized next-generation sequencing approaches to profile the Ab repertoire and ascertain frequencies of somatic hypermutation in colon biopsies from antiretroviral therapy-naive PWH versus controls. Our findings identify perturbations in the Ab repertoire of PWH that could contribute to development or maintenance of dysbiosis. Moreover, IgA mutations significantly decreased in PWH and this was associated with adverse clinical outcomes. These data may provide insight into the mechanisms underlying impaired Ab-dependent gut homeostasis during chronic HIV-1 infection.


Asunto(s)
Tracto Gastrointestinal , Infecciones por VIH , Inmunoglobulina A , Hipermutación Somática de Inmunoglobulina , Disbiosis , Tracto Gastrointestinal/inmunología , Tracto Gastrointestinal/virología , Infecciones por VIH/genética , Infecciones por VIH/inmunología , VIH-1 , Humanos , Inmunidad Humoral , Inmunoglobulina A/genética
11.
Opt Express ; 31(4): 6827-6848, 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36823931

RESUMEN

Detecting and avoiding obstacles while navigating can pose a challenge for people with low vision, but augmented reality (AR) has the potential to assist by enhancing obstacle visibility. Perceptual and user experience research is needed to understand how to craft effective AR visuals for this purpose. We developed a prototype AR application capable of displaying multiple kinds of visual cues for obstacles on an optical see-through head-mounted display. We assessed the usability of these cues via a study in which participants with low vision navigated an obstacle course. The results suggest that 3D world-locked AR cues were superior to directional heads-up cues for most participants during this activity.


Asunto(s)
Realidad Aumentada , Gafas Inteligentes , Baja Visión , Humanos , Señales (Psicología) , Interfaz Usuario-Computador
12.
J Pediatr Gastroenterol Nutr ; 76(5): 560-565, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36800285

RESUMEN

OBJECTIVE: The incidence and significance of pneumatosis intestinalis (PI) in children with a diagnosis of intestinal failure is not well understood. The aim of this study was to identify clinical and anatomical factors associated with the imaging findings of PI in patients with intestinal failure. METHODS: We performed a retrospective review of all children with a diagnosis of intestinal failure at Children's Hospital Colorado between January 2019 and April 2022. Patients were stratified and compared based on the incidence of PI on abdominal imaging. Differences were compared using 2-sample Wilcoxon tests, chi-square, or Fisher exact tests. RESULTS: There were 111 patients identified with a diagnosis of intestinal failure and 30.6% (34) developed at least 1 instance of PI. There were no differences in etiology of intestinal failure or anatomy between those who developed PI and those who did not. Patients who developed PI, were less likely to be on total parental nutrition (60.6% vs 98.6%, P < 0.001) and more likely to be receiving any form of enteral feeds (87.9% vs 66.2%, P = 0.035) or tube feeds (75.8% vs 44.2%, P = 0.0045). Of the children with PI, 30.3% (10) were undergoing an enteral feed advancement at time of PI development. Three patients with PI underwent laparotomy for PI treatment, 2 of which were negative laparotomies. CONCLUSIONS: The development of PI in children with intestinal failure is likely a benign finding. It is associated with enteral feeding and may be due to increased intestinal stress.


Asunto(s)
Insuficiencia Intestinal , Neumatosis Cistoide Intestinal , Humanos , Niño , Nutrición Enteral/efectos adversos , Nutrición Enteral/métodos , Intestinos , Estudios Retrospectivos , Colorado , Neumatosis Cistoide Intestinal/diagnóstico por imagen , Neumatosis Cistoide Intestinal/etiología
13.
Behav Sleep Med ; 21(3): 291-303, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35699363

RESUMEN

OBJECTIVES: To assess changes in duration, timing, and social jetlag in adolescent sleep during the COVID-19 pandemic and evaluate the impact of mood, physical activity, and social interactions on sleep. STUDY DESIGN: An online survey queried adolescents' sleep before (through retrospective report) and during the initial phase of COVID-19 in May 2020. Adolescents (N = 3,494), 13-19 years old, in the United States (U.S.) answered questions about their current and retrospective (prior to COVID-19) sleep, chronotype, mood, and physical and social activities. Linear regression models were fit for time in bed, reported bed and wake times, and social jetlag during COVID-19, accounting for pre-COVID-19 values. RESULTS: Total reported time in bed (a proxy for sleep duration) increased on weekdays by an average of 1.3 ± 1.8 hours (p < .001) during COVID-19, compared to retrospective report of time in bed prior to COVID-19. During COVID-19, 81.3% of adolescents reported spending 8 hours or more in bed on weekdays compared to only 53.5% prior to COVID-19. On weekdays, bedtimes were delayed on average by 2.5 hours and wake times by 3.8 hours during COVID-19 compared to prior to COVID-19. On weekends, bedtimes were delayed on average by 1.6 hours and waketimes by 1.5 hours (all p's < 0.001). Social jetlag of >2 hours decreased to 6.3% during COVID-19 compared to 52.1% prior to COVID-19. Anxiety and depression symptoms and a decline in physical activity during COVID-19 were associated with delayed bed and wake times during COVID-19. CONCLUSIONS: During COVID-19, adolescents reported spending more time in bed, with most adolescents reporting 8 hours of sleep opportunity and more consistent sleep schedules. As schools return to in-person learning, additional research should examine how sleep schedules may change due to school start times and what lessons can be learned from changes that occurred during COVID-19 that promote favorable adolescent sleep.


Asunto(s)
COVID-19 , Ritmo Circadiano , Humanos , Adolescente , Estados Unidos/epidemiología , Adulto Joven , Adulto , Duración del Sueño , Estudios Retrospectivos , Pandemias , Factores de Tiempo , Sueño , Síndrome Jet Lag/epidemiología , Encuestas y Cuestionarios
14.
J Vis ; 23(8): 13, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37585183

RESUMEN

For more than 2000 years, artists have exploited cast shadows to influence how objects appear to be positioned in a scene. A contact cast shadow can anchor an object to the ground and a detached cast shadow can make an object appear to float. However, there is a period of approximately 1000 years when there were virtually no cast shadows in art. How were states of contact versus floating depicted by artists without cast shadows? Here, we survey various techniques used by artists to anchor relative position with and without cast shadows. We then conduct experimental tests of the hypothesized surface attraction principles that underlie these techniques. In the absence of cast shadows, an object (a wooden box) was often seen as resting on a surface as long as that surface offered information about ground orientation and support (a tiled floor). When the ground surface was ambiguous and cloud-like (1/f noise), the box was more likely to be seen to float. The presence of cast shadows made the box appear to contact the ground whether it was well-defined or ambiguous. Both shadows and surface support also increased the accuracy with which participants detected when the box was tilted up from the ground. These results indicate that artists long ago discovered the important power of support relationships to anchor objects to surfaces in the absence of shadows.


Asunto(s)
Triazoles , Humanos , Encuestas y Cuestionarios
15.
J Vis ; 23(8): 10, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37552022

RESUMEN

Wearable optics have a broad range of uses, for example, in refractive spectacles and augmented/virtual reality devices. Despite the long-standing and widespread use of wearable optics in vision care and technology, user discomfort remains an enduring mystery. Some of this discomfort is thought to derive from optical image minification and magnification. However, there is limited scientific data characterizing the full range of physical and perceptual symptoms caused by minification or magnification during daily life. In this study, we aimed to evaluate sensitivity to changes in retinal image size introduced by wearable optics. Forty participants wore 0%, 2%, and 4% radially symmetric optical minifying lenses binocularly (over both eyes) and monocularly (over just one eye). Physical and perceptual symptoms were measured during tasks that required head movement, visual search, and judgment of world motion. All lens pairs except the controls (0% binocular) were consistently associated with increased discomfort along some dimension. Greater minification tended to be associated with greater discomfort, and monocular minification was often-but not always-associated with greater symptoms than binocular minification. Furthermore, our results suggest that dizziness and visual motion were the most reported physical and perceptual symptoms during naturalistic tasks. This work establishes preliminary guidelines for tolerances to binocular and monocular image size distortion in wearable optics.


Asunto(s)
Baja Visión , Dispositivos Electrónicos Vestibles , Humanos , Ojo , Refracción Ocular , Visión Ocular , Visión Binocular
16.
Pediatr Surg Int ; 39(1): 203, 2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37219695

RESUMEN

BACKGROUND: We aimed to identify prognostic indicators in pneumatosis intestinalis (PI) in a pediatric oncology population. We hypothesized that neutropenia would be an independent risk factor for adverse outcomes, including the need for abdominal operation to treat PI and for the development of recurrent PI. METHODS: We performed a retrospective review of all patients treated for PI between 2009 and 2019 with a diagnosis of cancer or history of bone marrow transplant (BMT). RESULTS: Sixty-eight children were treated for their first episode of PI; 15 (22%) were not neutropenic at presentation; eight underwent urgent abdominal operation (12%). Patients with neutropenia were more likely to receive TPN, had a longer course of NPO, and received a longer course of antibiotics. Neutropenia at presentation was associated with a decreased risk of PI recurrence (40% vs 13%, p = 0.03). Children who required an abdominal operation were more likely to require vasopressors at diagnosis (50% vs 10%, p = 0.013). CONCLUSIONS: Among pediatric cancer patients, need for vasopressors at the time of PI is a marker of severe PI, with increased likelihood of requiring operative intervention. The presence of neutropenia is associated with lower rates of PI recurrence. LEVEL OF EVIDENCE: Level III.


Asunto(s)
Neoplasias , Neutropenia , Niño , Humanos , Antibacterianos , Pacientes , Factores de Riesgo
17.
Pediatr Surg Int ; 39(1): 228, 2023 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-37422894

RESUMEN

PURPOSE: To assess fertility concerns and to describe pregnancy outcomes in patients with anorectal malformations (ARM). METHODS: This is an IRB approved, cross-sectional study of patients in the Adult Colorectal Research Registry who completed reproductive health surveys between November 2021 and August 2022. Patients assigned female at birth with age 18 or older and ARM were included. RESULTS: Sixty-four patients with ARM, age 18 or older, were included. Fertility concerns were reported in 26 (40.6%) patients, 11 of which had seen a fertility specialist, including four who had not yet tried to conceive. Fertility concerns were highest amongst cloaca patients who had not yet tried to conceive (37.5%). 26 (40.6%) patients had tried to conceive, of which 16 (25%) reported fertility problems, most frequently uterine abnormalities and damaged or blocked fallopian tubes. 22 (34.4%) participants were able to conceive and 18 (28.1%) had at least one live birth. Patients with ARM who had concerns of fertility, had better FertiQoL when compared to published reference scores for patients experiencing fertility issues. CONCLUSION: Providers should be aware of fertility concerns in patients with ARM. Proactive counseling with referrals to a fertility specialist should be considered in patients who desire future fertility.


Asunto(s)
Malformaciones Anorrectales , Anomalías Urogenitales , Embarazo , Adulto , Recién Nacido , Humanos , Femenino , Adolescente , Malformaciones Anorrectales/complicaciones , Malformaciones Anorrectales/cirugía , Estudios Transversales , Fertilidad , Resultado del Embarazo
18.
Pediatr Surg Int ; 39(1): 234, 2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37464109

RESUMEN

PURPOSE: To assess the quality of life and disease-specific functioning of adults with anorectal malformations (ARM) or Hirschsprung disease (HD) compared to healthy reference scores. METHODS: Patients with the diagnosis of ARM or HD from the Adult Colorectal Research Registry completed the Short Form 36 Health Survey (SF-36), the Gastrointestinal Quality of Life Index (GIQoLI), and the Bowel Function Score (BFS) between October 2019 and August 2022. One-sample Wilcoxon test compared the results to reported healthy references with a significance level of < 0.05. RESULTS: The response rate was 67%. All three surveys were completed by 133 adults with a slight preponderance of males (51%). Median age was 31 years, 117 were born with ARM and 16 with HD. All subgroups had significantly lower BFS than healthy references. ARM patients scored significantly lower than the healthy reference population when assessed for GIQoL. All showed significant impairment with the mental component summary (MCS) of SF-36. Patients with a successful bowel management had significantly higher scores on all three questionnaires than those with fecal accidents. CONCLUSION: Our results emphasize the importance of a successful bowel management and its impact on the quality of life and bowel function. Long-term follow-up is recommended with attention to mental health.


Asunto(s)
Malformaciones Anorrectales , Enfermedad de Hirschsprung , Masculino , Humanos , Adulto , Malformaciones Anorrectales/psicología , Calidad de Vida/psicología , Defecación , Enfermedad de Hirschsprung/diagnóstico , Encuestas y Cuestionarios
19.
Pediatr Emerg Care ; 39(7): 501-506, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37276058

RESUMEN

BACKGROUND: Two novel pediatric trauma scoring tools, SIPAB+ (defined as elevated SIPA with Glasgow Coma Scale ≤8) and rSIG (reverse Shock Index multiplied by Glasgow Coma Scale and defined as abnormal using cutoffs for early outcomes), which combine neurological status with Pediatric Age-Adjusted Shock Index (SIPA), have been shown to predict early trauma outcomes better than SIPA alone. We sought to determine if one more accurately identifies children in need of trauma team activation. METHODS: Patients 1 to 18 years old from the 2014-2018 Pediatric Trauma Quality Improvement Program database were included. Sensitivity and specificity for SIPAB+ and rSIG were calculated for components of pediatric trauma team activation, based on criteria standard definitions. RESULTS: There were 11,426 patients (1.9%) classified as SIPAB+ and 235,672 (39.0%) as having an abnormal rSIG. SIPAB+ was consistently more specific, with specificities exceeding 98%, but its sensitivity was poor (<30%) for all outcomes. In comparison, rSIG was a more sensitive tool, with sensitivities exceeding 60%, and specificity values exceeded 60% for all outcomes. CONCLUSIONS: Trauma systems must determine their priorities to decide how best to incorporate SIPAB+ and rSIG into practice, although rSIG may be preferred as it balances both sensitivity and specificity. LEVEL OF EVIDENCE: Level III.


Asunto(s)
Estudios Retrospectivos , Humanos , Niño , Lactante , Preescolar , Adolescente , Escala de Coma de Glasgow , Presión Sanguínea , Frecuencia Cardíaca/fisiología , Puntaje de Gravedad del Traumatismo
20.
Pain Pract ; 23(4): 338-348, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36527287

RESUMEN

OBJECTIVE: Cognitive behavioral therapy for chronic pain (CBT-CP) is an evidence-based treatment for improving functioning and pain intensity for people with chronic pain with extensive evidence of effectiveness. However, there has been relatively little investigation of the factors associated with successful implementation and uptake of CBT-CP, particularly clinician and system level factors. This formative evaluation examined barriers and facilitators to the successful implementation and uptake of CBT-CP from the perspective of CBT-CP clinicians and referring primary care clinicians. METHODS: Qualitative interviews guided by the Consolidated Framework for Implementation Research were conducted at nine geographically diverse Veterans Affairs sites as part of a pragmatic clinical trial comparing synchronous, clinician-delivered CBT-CP and remotely delivered, technology-assisted CBT-CP. Analysis was informed by a grounded theory approach. RESULTS: Twenty-six clinicians (CBT-CP clinicians = 17, primary care clinicians = 9) from nine VA medical centers participated in individual qualitative interviews conducted by telephone from April 2019 to August 2020. Four themes emerged in the qualitative interviews: (1) the complexity and variability of referral pathways across sites, (2) referring clinician's lack of knowledge about CBT-CP, (3) referring clinician's difficulty identifying suitable candidates for CBT-CP, and (4) preference for interventions that can be completed from home. CONCLUSIONS: This formative evaluation identified clinician and system barriers to widespread implementation of CBT-CP and allowed for refinement of the subsequent implementation of two forms of CBT-CP in an ongoing pragmatic trial. Identification of relative difference in barriers and facilitators in the two forms of CBT-CP may emerge more clearly in a pragmatic trial that evaluates how treatments perform in real-world settings and may provide important information to guide future system-wide implementation efforts.


Asunto(s)
Dolor Crónico , Terapia Cognitivo-Conductual , Automanejo , Telemedicina , Humanos , Dolor Crónico/terapia , Dolor Crónico/psicología
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