Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To define the expulsive and airway protective mechanisms involved in infantile regurgitation, we studied 15 infants (9 premature and 6 mature infants) with histories of frequent postfeeding regurgitation. In 13 infants we recorded pharyngeal pressure, pH, nasal and oral airflow, and abdominal respiratory movements. In two additional infants we recorded gastric pressure. In eight infants observations were made without intrapharyngeal recording devices. Distinctive abdominal regurgitation movements (RMs) immediately preceded 84% of regurgitation episodes. These RMs were characterized by one or more large brief increases in abdominal girth. In the two infants with gastric pressure recordings, large increases in gastric pressure, with duration and frequency characteristics similar to the RMs, immediately preceded regurgitation episodes. Thus, in contrast to the generally accepted concept that flow of gastric contents out of the stomach is passive during infantile regurgitation, we documented an active expulsive mechanism similar to that of vomiting in the adult. In all regurgitation episodes, upper airway closure occurred at the onset of the regurgitation movement. One or more swallows occurred immediately following RMs and prior to airway reopening in 97% of regurgitation episodes. Brief respiratory pauses occurred during regurgitation in all premature infants and occasionally in mature infants. Nasal regurgitation, coughing, and sneezing occasionally accompanied regurgitation episodes. Thus upper airway closure and swallowing prior to airway reopening were the most frequently observed airway protective mechanisms during regurgitation. Brief respiratory pauses, sneezing, and coughing may be secondary airway protective mechanisms. Nasal regurgitation likely represents immaturity of airway protective mechanisms.
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PMID:Airway protective and abdominal expulsive mechanisms in infantile regurgitation. 405 62

This is the first study to compare the influence of nasal afferent stimulation on inspiratory and expiratory muscle activity during sneezing, in kittens and adult cats. In kittens, we demonstrate that nasal afferent stimulation does not reinforce inspiratory activity prior to the expiratory thrust as it normally does in adult cats. These stimulations evoke an active expiration similar to but weaker than the expiratory thrusts observed under the same conditions during sneezing in adult cats. Sneezing can be elicited from three weeks of life. Among the different hypotheses discussed, the most likely explanation appears to be the immaturity of medullary respiratory connections.
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PMID:The sneeze: maturation of the reflex in kittens. 847 44

Studies of endoepithelial-triggered reflexes, such as nasal respiratory reflexes, are difficult to carry out in humans without a non-traumatic and reliable stimulation device. The air puff stimulator described allows us to deliver air puffs of brief duration at various intensities, frequencies, and temperatures. The stimulation is non-traumatizing and non-nociceptive. We have successfully used it in animals as a source of specific stimuli to enable us to study central and peripheral neuronal responses evoked by activation of endonasal dynamically sensitive receptors. Immunohistochemical studies of the c-fos expression evoked during sneezing elicited by air puffs provided additional evidence for the specificity of this particular stimulation technique. We suggest that the use of such a non-traumatizing air puff stimulator could be extended to human studies. It might be particularly useful in developmental studies of endoepithelial-triggered reflexes such as those respiratory reflexes whose immaturity at birth can be life-threatening.
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PMID:An improved mechanical air puff stimulator that allows activation of a variety of endoepithelial receptors and is suitable for the study of reflexes in animals and humans. 948 87

Coronaviruses are a large family of respiratory RNA viruses that can cause severe infections of the airways, as we have seen in the past, difficult months. We know that the route of transmission of the disease is through saliva droplets produced by speaking, coughing and sneezing. The virus is highly infectious, and each infected individual infects 2.5 people on average. The average incubation period is about 5 days, with an estimated range from 2 to 14 days; the incubation period in children is similar, however some have exhibited a longer incubation. The virus binds to the cellular receptor ACE2, which in children has a structural and functional immaturity thus offering lower affinity to the pathogen; this could explain the lower incidence of infection from SARS-CoV-2 in this segment of the population.The common clinical observation is that COVID-19 is less severe in children, and in this group the disease is often asymptomatic. Pending further clinical studies able to clarify the infection and transmission dynamics, it is therefore important to apply also in children all preventive and hygiene measures recommended by the health authorities during dental treatment. We should avoid procedures that generate aerosols as much as possible, minimising the use of the air syringe. When possible, it is recommended to employ minimally invasive procedures and ART (Atraumatic Restorative Treatment). The latter is a technique that can also be employed in very young and uncooperative patients with widespread carious lesions, in order to avoid more invasive and complex procedures. Ozone therapy could be of great help in the control of the progression of the asymptomatic carious lesions, especially during the Phase 2 of reopening, when we should to minimise the use of rotating instruments producing aerosols. The above introduces a new concept of "no aerosol" that will possibly guide our therapeutic choices not only in the immediate future but also in the long term, opening scenarios of prevention and cure that are more efficient, safe, and sustainable. During procedures that generate aerosols, the use of proper PPE is crucial to minimise the risk of transmission. It is also strongly recommended to work with an assistant, and to use double suction and a rubber dam. We will have to rethink and review the schedule of daily activities, in terms of timing and mode of delivery of care, on the basis of an agenda which can be divided into "no aerosol" and "aerosol" procedures, and "virtual visits" (including management of true emergencies), creating a virtuous optimisation of care for the safety of operators and office staff, as discussed in an article published on this very EJPD issue. In the coming months we will perhaps deliver more "patient-oriented" than "tooth-oriented" treatments, and this is true not only for young patients!
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PMID:COVID-19 and Paediatric Dentistry after the lockdown. 3256 38