Journal of Visual Impairment & Blindness最新文献

Background: Necrotizing enterocolitis (NEC) is an inflammatory gastrointestinal process that afflicts approximately 10% of preterm infants born in the United States each year, with a mortality rate of 30%. NEC severity is graded using Bell's classification system, from stage I mild NEC to stage III severe NEC. Over half of NEC survivors present with neurodevelopmental impairment during adolescence, a long-term complication that is poorly understood but can occur even after mild NEC. Although multiple animal models exist, none allow the experimenter to control nor represent the gradient of symptom severities seen in NEC patients. We bridge this knowledge gap by developing a graded murine model of NEC and studying its relationship with neuroinflammation across a range of NEC severities.

Methods: Postnatal day 3 (P3) C57BL/6 mice were fed a formula containing different concentrations (0% control, 0.25%, 1%, 2%, and 3%) of dextran sodium sulfate (DSS). P3 mice were fed every 3 hours for 72-hours. We collected data on weight gain and behavior (activity, response, body color) during feeding. At the end of the experiment, we collected tissues (intestine, liver, plasma, brain) for immunohistochemistry, immunofluorescence, and cytokine and chemokine analysis.

Results: Throughout NEC induction, mice fed higher concentrations of DSS died sooner, lost weight faster, and became sick or lethargic earlier. Intestinal characteristics (dilation, color, friability) were worse in mice fed with higher DSS concentrations. Histology revealed small intestinal disarray among mice fed all DSS concentrations, while higher DSS concentrations resulted in reduced small intestinal cellular proliferation and increased hepatic and systemic inflammation. In the brain, IL-2, G-CSF, and CXCL1 concentrations increased with higher DSS concentrations. Although the number of neurons and microglia in the CA1 hippocampal region did not differ, microglial branching was significantly reduced in DSS-fed mice.

Conclusion: We characterize a novel graded model of NEC that recapitulates the full range of NEC severities. We show that mild NEC is sufficient to initiate neuroinflammation and microglia activation. This model will facilitate studies on the neurodevelopmental effects of NEC.

Introduction: Research supports the benefits of job search interventions in improving employment outcomes for various populations, but previous studies involved face-to-face implementation and did not include adults with visual impairments. The purpose of this study was to investigate the feasibility and acceptability of a job search intervention designed for synchronous distance implementation with adults with visual impairments.

Methods: Two trainers implemented a 5-day job search skills training program with 12 job seekers with visual impairments, ages 22 to 63 years, via Zoom videoconferencing software. Researchers documented participant attendance and intervention fidelity during the program. Participants completed electronic surveys that included quantitative measures of cognitive load and acceptability, plus open-ended questions about their overall perceptions of the program.

Results: Attendance, intervention fidelity, and germane cognitive load were high, whereas intrinsic and extraneous cognitive load were low. Most implementation issues resulted from participants' technical difficulties, which were most prevalent on the first day. Acceptability ratings indicated high levels of engagement; relevance; interactivity; and satisfaction with the trainers, group processes, and virtual format. Participants commented on many positive aspects of the program, and some acknowledged the technical issues that occurred.

Discussion: The results support the acceptability and feasibility of the job search intervention. The trainers successfully implemented the program via videoconferencing with adults with visual impairments and developed a positive group atmosphere with high social support.

Implications for practitioners: Our findings have implications for facilitating group interventions through videoconferencing, including strategies for building group cohesion and social support.