Publications by authors named "Donald Bartlett"

What is the central question of this study? Does activation of serotonergic neurons in the caudal medullary raphe, some of which project to the nucleus of the solitary tract, shorten the laryngeal chemoreflex? What is the main finding and its importance? We found that serotonin originating from neurons in the caudal raphe acts through a 5-HT receptor located in the nucleus of the solitary tract to terminate reflex apnoea. Failure or deficiency of this arousal-related process is likely to be relevant to the pathogenesis of sudden infant death syndrome. Failure to terminate apnoea and arouse is likely to contribute to sudden infant death syndrome (SIDS).

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Thermal stress and prior upper respiratory tract infection are risk factors for the Sudden Infant Death Syndrome. The adverse effects of prior infection are likely mediated by interleukin-1β (IL-1β). Therefore, we examined the single and combined effects of IL-1β and elevated body temperature on the duration of the Laryngeal Chemoreflex (LCR) in decerebrate neonatal piglets ranging in age from post-natal day (P) 3 to P7.

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What is the central question of this study? Failure to terminate apnoea and arouse is likely to contribute to sudden infant death syndrome (SIDS). Serotonin is deficient in the brainstems of babies who died of SIDS. Therefore, we tested the hypothesis that serotonin in the nucleus of the solitary tract (NTS) would shorten reflex apnoea.

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We measured the duration of apnea induced by sustained end-inspiratory lung inflation (the Hering Breuer Reflex, HBR) in unanesthetized infant rat pups aged 4 days (P4) to P20 at body temperatures of 32°C and 36°C. The expiratory prolongation elicited by the HBR lasted longer in the younger pups and lasted longer at the higher body temperature. Blockade of adenosine receptors by caffeine following injection into the cisterna magna (ICM) significantly blunted the thermal prolongation of the HBR.

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Background: Individuals with serious mental illnesses (SMI) represent a high-risk health disparities population disproportionately affected by diabetes and obesity.

Objectives: This paper describes a community-based participatory research (CBPR) approach to adapting a well-known evidence-based behavioral change protocol, the Diabetes Prevention Program (DPP) lifestyle intervention, for individuals with diabetes and SMI in the community setting.

Methods: A committee composed of university researchers and representatives from the recovery community modified the DPP following three criteria: Person centeredness, practicality, and empowerment.

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Many articles in this section of Comprehensive Physiology are concerned with the development and function of a central pattern generator (CPG) for the control of breathing in vertebrate animals. The action of the respiratory CPG is extensively modified by cortical and other descending influences as well as by feedback from peripheral sensory systems. The central nervous system also incorporates other CPGs, which orchestrate a wide variety of discrete and repetitive, voluntary and involuntary movements.

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Elevating body temperature or just the temperature of the dorsal medulla by approximately 2°C prolongs the laryngeal chemoreflex (LCR) in decerebrate neonatal piglets. We tested the hypothesis that transient receptor potential vanilloid 1 (TRPV1) receptors in the nucleus of the solitary tract (NTS) mediate thermal prolongation of the LCR. We studied the effect of a selective TRPV1 receptor antagonist on thermal prolongation of the LCR, and we tested the effect of a TRPV1 agonist on the duration of the LCR under normothermic conditions.

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Hyperthermic prolongation of the laryngeal chemoreflex (LCR) in decerebrate piglets is prevented or reversed by GABA(A) receptor antagonists and adenosine A(2A) (Ad-A(2A)) receptor antagonists administered in the nucleus of the solitary tract (NTS). Therefore, we tested the hypothesis that enhanced GABA(A) activity and administration of the Ad-A(2A) agonist, CGS-21680, would prolong the LCR in normothermic conditions. We studied 46 decerebrate piglets ranging from 3 to 8 postnatal days of age.

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Objectives: Gold Choice, a partially capitated Medicaid managed care programme for individuals with a behavioural health diagnosis, implemented a telephonic nurse case management (TNCM) programme to improve diabetes self-management. We sought to identify issues faced by patients with co-morbid behavioural health diagnoses and diabetes as documented in the telephonic nurse case manager's progress notes. We also explored the role of the TNCM in addressing members' needs.

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Laryngeal chemoreflex (LCR) apnea occurs in infant mammals of many species in response to water or other liquids in the laryngeal lumen. The apnea can last for many seconds, sometimes leading to dangerous hypoxemia, and has therefore been considered as a possible mechanism in the Sudden Infant Death Syndrome (SIDS). We have found recently that this reflex is markedly prolonged in decerebrate piglets and anesthetized rat pups that are warmed 1-3 degrees C above their normal body temperatures.

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Hyperthermia prolongs the laryngeal chemoreflex (LCR). Under normothermic conditions, adenosine antagonists shorten and adenosine A(2A) (Ad-A(2A)) agonists prolong the LCR. Therefore, we tested the hypothesis that SCH-58261, an Ad-A(2A) receptor antagonist, would prevent thermal prolongation of the LCR when injected unilaterally within the nucleus of the solitary tract (NTS).

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We investigated the interaction between body temperature and the duration of the laryngeal chemoreflex (LCR) in decerebrate piglets. Elevating body temperature by approximately 2 degrees C prolongs the duration of the LCR and the length of apnea associated with the reflex. This thermal prolongation seems to arise within the nucleus of the solitary tract in the brainstem, and we believe the thermal effect is mediated by enhanced GABAergic neurotransmission.

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In neonatal mammals of many species, including human infants, apnea and other reflex responses frequently arise from stimulation of laryngeal receptors by ingested or regurgitated liquids. These reflexes, mediated by afferents in the superior laryngeal nerves (SLNs), are collectively known as the laryngeal chemoreflex (LCR) and are suspected to be responsible for some cases of the sudden infant death syndrome (SIDS). The LCR is strongly enhanced by mild increases in body temperature in decerebrate piglets, a finding that is of interest because SIDS victims are often found in overheated environments.

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The laryngeal chemoreflex (LCR) is elicited by water in the larynx and leads to apnea and respiratory disruption in immature animals. The LCR is exaggerated by the elevation of brain temperature within or near the nucleus of the solitary tract (NTS) in decerebrate piglets. Thermal prolongation of reflex apnea elicited by superior laryngeal nerve stimulation is reduced by systemic administration of GABA(A) receptor antagonists.

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Purpose: The purpose of this pilot study was to determine the effectiveness of an edited Diabetes Prevention Program (DPP) Lifestyle Resources Core Teaching Plan for managing patients with type 2 diabetes in an urban underserved setting. Modifications were made to attempt to cut to the bare essentials to work within the constrained budgets of safety net providers. The primary aim was to achieve a mean absolute reduction in HbA1c level of 1 percentage point.

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We tested the hypotheses that elevated body temperature would prolong reflex apnea following electrical stimulation of the superior laryngeal nerve (SLN) in decerebrate neonatal piglets and that thermal prolongation of reflex apnea after stimulation of the SLN depended on GABAergic mechanisms. These studies were conducted in 13 decerebrate piglets (age 3-15 days). The SLN was stimulated at approximately 1.

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Healthy eating and increased physical activity can prevent or delay diabetes and its complications. Techniques that facilitate adherence to these lifestyle changes can be adapted to primary care. Often, the patient's readiness to work toward change must be developed gradually.

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We tested the hypothesis that inhibition of neurons within the rostral ventral medulla (RVM) would prolong the laryngeal chemoreflex (LCR), a putative stimulus in the sudden infant death syndrome (SIDS). We studied the LCR in 19 piglets, age 3-16 days, by injecting 0.05 ml of saline or water into the larynx during wakefulness, non-rapid eye movement (NREM) sleep, and REM sleep, before and after 1 or 10 mM muscimol dialysis in the RVM.

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