The effects of mild hypoxia on hypoglossal motoneurones in neonates

The patency of the upper airway is dependent on the activity of the genioglossus muscle, the main protrusor muscle of the tongue. The force generated by this muscle opposes the negative intraluminal pressure produced by the contraction of the diaphragm during inspiration. Recent studies suggest that there is an immaturity in genioglossus muscle control in neonates and obstructive apnoea may occur when the activity of this muscle is reduced or absent without a corresponding decrease in the activity of the diaphragm. However, little is known of the processes mediating and influencing the activity of the hypoglossal nerve, the motor nerve of the genioglossus muscle, at this stage in development. In newborn babies, central apnoea (when there is no inspiratory effort) is usually followed by obstructive apnoea (when although there is inspiratory effort there is no inspiratory flow). It is therefore possible that hypoxia which develops during central apnoea, inhibits the activity of the genioglossus muscle and as a consequence the airway becomes obstructed. The aim of this study was therefore to determine whether hypoglossal motoneurones are inhibited during hypoxia in neonates. This study has investigated the effect of mild levels of hypoxaemia (PaO2 47.2 ± 3.8mmHg) on the activity of hypoglossal motoneurones in anaesthetized neonatal kittens (27 days old). The results showed that the majority of hypoglossal motoneurones increased in discharge frequency during hypoxia but for a substantial proportion the increase was only transient. Furthermore, some motoneurones showed a decrease in discharge frequency. Intracellular recordings showed that during similar levels of hypoxia, although a large proportion of the motoneurones were depolarized, at least some of these repolarized despite the continuing hypoxia. In addition, some hypoglossal motoneurones were hyperpolarized. This is the clearest evidence that inhibitory mechanisms, in addition to excitatory mechanisms, mediate the effects of hypoxia on hypoglossal output in neonates. Furthermore, the results suggest that hypoxia has an effect on the hypoglossal motoneurones independently of, or in addition to, its effect through respiratory rhythm. In some preliminary studies, the transmembrane input resistance increased during the hyperpolarization in response to hypoxia. One possibility is that the inhibition is mediated by the removal of an excitatory input. If the inhibition found in this study occurs in human babies it may be a compounding factor in apnoeas of the newborn

Unmet Support Needs of Informal Caregivers of Older Adults

Due to projected growth of the 65-and-older population and concerns of an impending care gap, reliance on informal caregivers is expected to increase. Improving support for informal caregivers is viewed as a national priority, yet research related to the unmet support needs of informal caregivers is limited. The purpose of this cross-sectional correlational study was to examine predictive relationships between contextual factors (caregiving relationship and type of illness) and environmental factors (rurality) and the unmet support needs (classes, service access, support groups, counseling, and respite) of informal caregivers of older adults. The theoretical framework was Bronfenbrenner\u27s ecological systems theory. Archival data were drawn from the 2015 Behavioral Risk Factor Surveillance System optional caregiver module dataset provided by the Centers for Disease Control and Prevention. Findings from multiple logistic regression analysis revealed that spousal caregivers had 42.7% lower odds than adult child caregivers of reporting unmet support needs related to service access. Dementia caregivers had 2.05 times higher odds of reporting unmet support needs of counseling, 1.31 times higher odds of reporting unmet support needs related to service access, and 1.91 times higher odds of reporting unmet support needs for respite care, relative to other caregivers. Caregivers residing in a suburban county had 28.7% lower odds and caregivers not residing in a metropolitan statistical area (MSA) had 30.5% lower odds of reporting unmet support needs related to service access, relative to caregivers residing in the center city of an MSA. Health care leaders and policymakers may use the findings to distribute resources and tailor interventions to better meet the needs of informal caregivers of older adults

A Qualitative Study on Mother\u27s Occupational Engagement After a NICU Experience

Mothers who are “at-risk” for complications during pregnancy have an increased probability for mental health conditions following delivery, adversely affecting their engagement in motherhood occupations. This qualitative study identifies how best to address the needs of “at-risk” pregnant women. Through the process of conducting semi-structured interviews with women who have experienced NICU with their babies, and interviews with healthcare practitioners working in the NICU, their narrative addresses what approaches would support women while they are going through their “at-risk” pregnancies to assist them with the transition to their occupational roles as mothers and promote bonding with their baby.https://soar.usa.edu/otdcapstonesspring2024/1036/thumbnail.jp

Do paramedics have a professional obligation to work during a pandemic? A qualitative exploration of community member expectations

Objectives: Previous research has identified a lack of clarification regarding paramedic professional obligation to work. Understanding community expectations of paramedics will provide some clarity around this issue. The objective of this research was to explore the expectations of a sample of Australian community members regarding the professional obligation of paramedics to respond during pandemics. Methods: The authors used qualitative methods to gather Australian community member perspectives immediately before the onset of the coronavirus disease 2019 (COVID-19) pandemic. Focus groups were used for data collection, and a thematic analysis was conducted. Results: The findings revealed 9 key themes: context of obligation (normal operations versus crisis situation), hierarchy of obligation (individual versus organizational obligation), risk acceptability, acceptable occupational risk (it’s part of the job), access to personal protective equipment, legal and ethical guidelines, education and training, safety, and acceptable limitations to obligation. The factors identified as being acceptable limitations to professional obligation are presented as further sub-themes: physical health, mental health, and competing personal obligations. Conclusions: The issue of professional obligation must be addressed by ambulance services as a matter of urgency, especially in light of the COVID-19 coronavirus pandemic. Further research is recommended to understand how community member expectations evolve during and after the COVID-19 coronavirus pandemic

Loss of Cone Molecular Markers in Rhodopsin-Mutant Human Retinas with Retinitis Pigmentosa

Purpose: To examine the effect of rhodopsin mutations on cone photoreceptors in human retinas with retinitis pigmentosa (RP). Methods: Four RP retinas with rhodopsin mutations and four normal retinas were examined by immunofluorescence with a battery of cell-specific antibodies against cone and rod cytoplasmic and outer segment membrane proteins. Areas of the retinas were studied that showed maximal preservation of photoreceptor structure. Results: All four RP retinas showed loss of rods, ranging from mild (T-17-M), to more severe (P-23-H), to advanced degeneration (Q-64-ter and G-106-R). The majority of cones in the T-17-M and P-23-H retinas were cytologically normal but showed loss of immunoreactivity for the cytoplasmic proteins 7G6, calbindin, and X-arrestin. The cone outer segments (OS) remained positive for cone opsins and peripherin-2 (rds/peripherin). All remaining cones in the Q-64-ter and G-106-R retinas were degenerate, with short to absent OS, but had strong reactivity for these cytoplasmic and OS membrane markers. Cones in the maculas of the RP retinas were degenerate, with short to absent OS, but retained strong labeling for the cytoplasmic and OS proteins. Conclusions: Even before cones show cytologic changes in response to rod cell degeneration, they lose immunoreactivity for certain cytoplasmic proteins. These cones later show shortening and loss of OS, although their OS membrane proteins remain well labeled. Cones may down regulate expression of both cytoplasmic and outer segment membrane proteins in response to mutant rod cell dysfunction and/or cell death in human RP retinas. Such cytologic and immunocytochemical changes in the cones may presage death of these critical cells in the later stages of RP

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Detection of potentially toxic metals by SERS using salen complexes

Surfaced enhanced Raman scattering (SERS) can discriminate between metal complexes due to the characteristic “spectral fingerprints” obtained. As a result, SERS has the potential to develop relatively simple and sensitive methods of detecting and quantifying a range of metal ions in solution. This could be beneficial for the environmental monitoring of potentially toxic metals (PTMs). Here, salen (C16H16N2O2) was used as a ligand to form complexes of Ni(II), Cu(II), Mn(II) and Co(II) in solution. The SERS spectra showed characteristic spectral differences specific to each metal complex, thus allowing the identification of each of these metal ions. This method allows a number of metal ions to be detected using the same ligand and an identical preparation procedure. The limit of detection (LOD) was determined for each metal ion, and it was found that Ni(II), Cu(II) and Mn(II) could be detected below the WHO’s recommended limits in drinking water at 1, 2 and 2 µg L-1, respectively. Co(II) was found to have an LOD of 20 µg L-1, however no limit has been set for this ion by the WHO as the concentration of Co(II) in drinking water is generally <1-2 μg L-1. A contaminated water sample was also analysed where Mn(II) was detected at a level of 800 µg L-1

Feasibility of single-cell analysis of model cancer and foetal cells in blood after isolation by cell picking

The objective of the present feasibility study was to transfer single cell line cells to either microscopy slides for downstream immune characterization or to polymerase chain reaction tubes for downstream DNA quantitation. Tumour cell lines, SKBR3 and MCF7 and trophoblast cell line JEG-3 were spiked in healthy donor blood. The CytoTrack system was used to scan the spiked blood samples to identify target cells. Individual target cells were identified, picked by use of a CytoPicker and deposited to either a microscopic slide or a polymerase chain reaction tube (PCR). Single tumour cells on microscopic slides were further immunostained with human epidermal growth factor receptor 2 (Her2) and epithelial cell adhesion molecule (EpCAM). From the picked cells in polymerase chain reaction tubes, DNA was amplified, quantified and used for Short Tandem Repeat genotyping. Depositing rare cells to microscopy slides was laborious with only five cells per hour. In this study with a trained operator, the picked cells had an 80.5% recovery rate. Depositing single trophoblast cells in PCR tubes was a faster process with 10 cells in 5 min. Immunostaining of isolated cells by both Her2 and EpCAM was possible but showed varying staining intensity. Presence of trophoblasts and contaminating white blood cells in PCR tubes after cell picking was confirmed based on DNA yield and mixed Short Tandem Repeat profiles in five out of eight samples. Using the CytoPicker tool, single tumour and trophoblast cells were successfully isolated and moved from blood samples, allowing subsequent immunostaining or Short Tandem Repeat genotyping

RCRA Monitoring Database Development Project

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