Characterization of the acute pulse transit time response to obstructive apneas and hypopneas in preschool children with sleep-disordered breathing

Background

Surges in heart rate (HR) and blood pressure (BP) at apnea termination contribute to the hypertension seen in obstructive sleep apnea (OSA). Because childhood OSA prevalence peaks in the preschool years, we aimed to characterize the cardiovascular response to obstructive events in preschool-aged children.

Methods

Clinically referred children aged 3–5 years were grouped by obstructive apnea–hypopnea index (OAHI) into the following: primary snoring (PS) (OAHI ? 1 event/h [n = 21]), mild OSA (OAHI > 1– ? 5 [n = 32]), and moderate to severe (MS) OSA (OAHI > 5 [n = 28]). Beat-to-beat pulse transit time (PTT), an inverse continuous indicator of BP changes, and HR were averaged during the two halves (early and late) and during the peak after (post) each obstructive event and were expressed as percentage change from late- to post-event.

Results

We analyzed 422 events consisting of 55 apneas and 367 hypopneas. A significant post-event increase in HR and fall in PTT occurred in all severity groups (P < .05 for all). A greater response was associated with OSA, nonrapid eye movement sleep (NREM), cortical arousal, hypopneas, and oxygen desaturation (P < .05 for all).

Conclusions

Obstructive events elicit acute cardiovascular changes in preschool children. Such circulatory perturbations have been implicated in the development of hypertension, and our findings complement previous studies to suggest a cumulative impact of snoring on the cardiovascular system from childhood into adulthood.     

Linking Gambling and Trauma: A Phenomenological Hermeneutic Case Study Using Almaas’ Transformation of Narcissism Approach

The purpose of this article is to examine the phenomenon of pathological gambling and addiction from the perspective of writer and teacher A.H Almaas. By drawing on his Diamond Mind approach we trace the origin of addictive behaviors and pathological gambling to narcissistic wounding, which constitutes the loss of connection with the Essential Identity. A phenomenological hermeneutic methodology was applied in the research process in which Penny, the subject of this case study, willingly shared her life journey through addiction. A thematic analysis clustered into 5 themes revealed a link between her experiences of childhood trauma, addiction, pathological gambling, and the manifestation of fundamental narcissism.     

Assessing the validity of multiple‐choice questions for RAPP story comprehension

Background: Passage dependency (PD) is a measure of how much information is required to answer test questions based only on information provided in the relevant text (Tuiman, 1974). Prior learning, information included in other test questions or responses, and the ability to eliminate less plausible or irrelevant foils are all factors that may affect PD. The PD of the multiple‐choice questions for the auditory story comprehension task in the RAPP software environment has yet to be established. Aims: The purpose of this experiment was to investigate the validity of newly developed multiple‐choice comprehension questions for the story comprehension tasks used in the RAPP software environment. Methods & Procedures: Participants were 40 young adults without speech or language impairment, 20 of whom heard each of 12 stimulus stories and answered 10 multiple‐choice questions with 5 response choices, and 20 who answered the multiple‐choice questions but were not exposed to the stimulus stories. Questions concerned information about stated and implied main ideas and details presented in the stories. Based on four pre‐determined story forms (three stories each), analyses examined the questions' validity in terms of their PD compared to chance performance and to a pre‐established Passage Dependency Index (PDI) criterion (.60). Significant differences in the PDI and in the percentage of correctly answered questions among predetermined forms were also evaluated. Analyses also examined the PD of questions based on the type of information queried both within and among forms. Outcomes & Results: Results provide support for the validity of the multiple‐choice questions without consideration of the nature of the information queried by them. The percentage of correctly answered questions exceeded chance for all story forms, PDIs met or exceeded the pre‐established criterion, there were no significant differences in the PDIs among the four forms and there were no significant differences in the percentage of correctly answered questions among the four forms. There were no significant differences in the PDIs among the four question types by story form or among question types within a form and all PDIs met or exceeded pre‐established criteria (except detail implied questions in one form). Conclusions: These results provide support for the PD of the multiple‐choice questions constructed for the four story forms that make up this version of a story‐length auditory comprehension task. Results suggest that the questions are not biased relative to the content of the stories and results add to the overall validity of the task.     

Natural tissue concentrations in adult Ambystoma maculatum and larval DNA damage from exposure to arsenic and chromium

Arsenic (As) and chromium (Cr) are two contaminants that are detected in aquatic and terrestrial habitats. Using the spotted salamander, Ambystoma maculatum, to assess impacts from these contaminants may be advantageous as adults live and breed in such environments. Adult amphibians typically exhibit elevated tissue concentrations of contaminants present in their environment, while larval stages were found to exhibit increased sensitivity to pollutants. From January through March of 2015, during the spring breeding season, 5 adults and approximately 32 egg masses were collected from a local breeding site. Field levels of As and Cr ranged from 5.99 to 8.88 µg/L and 1.45 to 2 µg/L, respectively, while mean adult As tissue concentrations were 56.74 µg/g dry weight for heart, 0.92 µg/g for liver, and 1.21 µg/g for tail tissue. Mean tissue concentrations for Cr were 87.64 µg/g for heart, 1.47 µg/g for liver, and 6.92 µg/g for tail. Developing larvae that were collected from the field and exposed in a lab setting for 12 d to 0.2 or 20 mg/L of either As or Cr displayed little DNA damage attributed to As, but marked damage due to exposure to 20 mg/L Cr when assessed using the comet assay. Exposure to a mixture of either 0.25:0.1 or 25:10 mg/L As and Cr resulted in significant DNA damage at the lower concentration of 0.25:0.1 mg/L. As adult spotted salamanders were found to possess high concentrations of these contaminants in cardiac tissue, and larvae were shown to be susceptible to DNA damage from increased exposures, assessing impacts and potential declines of amphibian populations exposed to As and Cr is needed.     

Conservative aesthetic techniques for discoloured teeth: 2. Microabrasion and composite

The first article in this series discussed the minimal intervention approach to discoloured teeth, starting with dental bleaching. This second article goes on to explain the technique of microabrasion and the use of direct composite techniques. CLINICAL RELEVANCE: Microabrasion and composite can provide minimally invasive treatments for discoloured teeth.