Search Results (6)

Vomiting, a key defence against accidentally ingested toxins, is widely present in mammals. Notably, rodents (e.g., rats, mice) are generally assumed to be unable to vomit, as commonly reported over the last ~100 years, but they are used extensively for biological and particularly biomedical research. However, three recent mouse papers reported ‘emetic-like’ responses induced by substances that are emetics in humans. Therefore, we critically re-examined the literature underpinning this longstanding view, integrating the recent and largely overlooked historical evidence challenging this consensus. We reappraise the ability of rodents to retch and vomit, concluding that whilst there is some published evidence for retching, the ability to vomit is unproven and for a range of physiological and anatomical reasons (e.g., organisation of the gastroesophageal anti-reflux barrier), it would be problematic. Experimentally testable hypotheses to explain the conflicting findings are proposed, together with criteria that should be fulfilled to define a behaviour as retching or vomiting in rodents. A detailed comparison is made of the physiological and anatomical differences between rodents and species known to vomit. We consider the significance of our conclusions for biomedical research, particularly in relation to the digestive tract and central nervous system, and the wider implications for rodent biology. Full article

Background/Objective: Gastroesophageal reflux disease (GERD) is multifactorial and affects an increasing number of people. It is a common condition in which the stomach contents move up into the esophagus; thus, its main cause is found in the antireflux valve mechanism of the gastroesophageal junction. This consists of two sphincters, the lower oesophageal and the diaphragmatic. The disease has been related to diaphragm dysfunction, either due to the de-coordination of the diaphragms’ contractility or due to decreased strength. Breathing exercises seem to have a positive effect in this population. The aim of this study was to systematically examine the effects of inspiratory muscle training (IMT) on GERD characteristics. Methods: We conducted a systematic review of research up to April 2024 in Scopus, PubMed, and Science Direct. We included randomized controlled trials (RCTs) and clinical trials assessing the effects of IMT on GERD characteristics. Methodological quality was assessed with the PEDro scale (Physiotherapy Evidence Database) and the Newcastle Ottawa scale (NOC). Results: Among the 1984 studies identified from the search, only three studies (one study with a post-COVID-19 population and two with GERD and healthy subjects) were included in this study, as they presented a fair to high methodological quality. Significant improvements in maximal inspiratory pressure (p < 0.001) and diaphragmatic excursion (p < 0.001) were revealed in one study. No significant differences between groups were mentioned for the reflux symptoms and for LES–EGJ pressure in the studies included. Conclusions: IMT seems to provide promising effects in strengthening the antireflux valve mechanism, as it increases MIP and diaphragmatic excursion. This systematic review established a bibliographic gap for the contribution of IMT in the antireflux valve mechanism. More evidence is needed to support the importance of IMT as a non-pharmacological intervention for GERD patients. Full article

Background/Objectives: Tacrine is a centrally active non-competitive reversible acetylcholinesterase inhibitor. It also exerts antagonising activity against N-methyl-D-aspartate receptors. Tacrine was approved for the treatment of Alzheimer’s disease in 1993, but was withdrawn from clinical use in 2013 because of its hepatotoxicity and gastrointestinal side effects. Nevertheless, tacrine is currently facing a renewed wave of interest primarily due to several new tacrine-incorporated hybrids and derivates. There were two specific aims for this study: firstly, to explain the mechanisms of the adverse action of tacrine, as a distinctive example of a highly effective acetylcholinesterase inhibitor; and secondly to check whether luminal impedance planimetry is feasible for preclinical testing of possible side effects of compounds potentially toxic to the gastrointestinal tract. Methods: Six experimental pigs were used as the animal model in this study. Five major parameters were evaluated: luminal pressure (mmHg), estimated diameter (mm), cross-sectional area (mm²), distensibility (mm²/mmHg), and zone compliance (mm³/mmHg). All measurements were performed before and 360 min after intragastric administration of 200 mg tacrine (at the porcine tacrine T_max). Results: This study consistently demonstrated an increase in luminal pressure (a directly measured indicator) for the particular balloon filling volumes used, and inversely a reciprocal decrease in the other parameters after tacrine administration. Conclusions: Endoscopic luminal impedance planimetry is a feasible method to evaluate functional response of the lower oesophageal sphincter to tacrine in experimental pigs. Tacrine did not compromise the function of the lower oesophageal sphincter either toward oesophageal spasms or, in contrast, decreased competence of the lower oesophageal sphincter. Full article

Fluid thickening is a valid therapeutic strategy for patients with oropharyngeal dysphagia (OD). The main aim of this study was to determine the therapeutic effect of the xanthan-gum-based thickener Tsururinko Quickly (TQ, Morinaga Milk Co., Tokyo, Japan) in older patients with severe OD. A total of 85 patients (83.32 ± 6.75 y) with OD and a penetration–aspiration score (PAS) of n ≥ 3 were studied by videofluoroscopy while swallowing duplicate 10 mL boluses at <50 mPa·s, 100, 200, 400, 800, and 1600 mPa·s, to assess the safety and efficacy of swallowing and the biomechanics of a swallowing response at each viscosity level. At <50 mPa·s, only 16.25% patients swallowed safely, 45% had penetrations (PAS 3–5), and 38.75% had aspirations (PAS 6–8). Fluid thickening with TQ greatly increased the prevalence of patients with safe swallowing from 62.90% at 100 mPa·s to 95.24% at 1600 mPa·s in a shear-viscosity-dependent manner. The penetrations and aspirations were significantly reduced to 3.60% and 1.19%, respectively, at 1600 mPa·s. The threshold viscosity was 100 mPa·s and the increasing viscosity above 800 mPa·s did not further improve the therapeutic effect significantly. Increasing the shear viscosity significantly reduced the time to laryngeal vestibule closure (−16.70%), increased the time to upper oesophageal sphincter opening (+26.88%), and reduced the pharyngeal bolus velocity (−31.62%) without affecting the pharyngeal residue. TQ has a strong shear-viscosity-dependent effect on the safety of swallowing in older patients with severe OD without increasing the pharyngeal residue. The therapeutic range for TQ is 100–800 mPa·s, with 200 and 800 mPa·s being the optimal doses to cover the needs of older patients with OD. Full article

The aims of gastroesophageal reflux disease (GERD) treatment are symptom relief and healing of oesophagitis. Besides proton pump inhibitors (PPIs), prokinetic agents are also commonly prescribed to treat GERD. Domperidone, a well-known antiemetic, is an example of a prokinetic agent. It is a dopaminergic blocker that increases lower oesophagus sphincter pressure and activates gastric motility. We carried out a systematic review and meta-analysis to explore the benefits of domperidone in addition to PPI therapy for GERD. We searched for publications comparing PPI plus domperidone to PPI monotherapy in terms of symptom improvement in GERD (until 21 April 2022) on PubMed, Scopus, Google Scholar, Web of Science, Cochrane Library, WHO’s International Clinical Studies Registry Platform, and ClinicalTrials.gov without restricting date, language, or study design. The protocol was registered in PROSPERO (CRD42021242076). This meta-analysis incorporated 11 studies with a total of 841 participants (419 in the PPI plus domperidone group and 422 in the PPI monotherapy group). The combination of a PPI and domperidone resulted in a significant reduction in global GERD symptoms. Adverse events associated with PPI plus domperidone treatment were similar to those associated with PPI monotherapy. In conclusion, the combination of domperidone and a PPI is generally safe and effective in treating GERD as compared with that of PPI alone. Full article

The aim of the study was to analyse the disturbances of the oro-pharyngeal swallowing phase of dysphagia in amyotrophic lateral sclerosis (ALS) patients with the use of specific manometric measurements and to evaluate their plausible association with the duration of the disease. Seventeen patients with ALS were evaluated with manometric examinations of the oral and pharyngeal part of the gastrointestinal tract. Tests were carried out by using the oesophageal balloon-based method with four balloon transducers located 5 cm away from each other. The following manometric parameters were analysed: the base of tongue contraction (BTC) and the upper oesophageal sphincter pressure (UESP), and the hypopharyngeal suction pump (HSP) as well as the oro-pharyngeal, pharyngeal and hypopharyngeal transit time and average pharyngeal bolus velocity (oropharyngeal transit time (OTT), pharyngeal transit time (PTT), hypopharyngeal transit time (HTT) and average pharyngeal bolus velocity (APBV), respectively). Manomatric examinations during swallowing in patients with ALS showed significant weakness of BTC, a decrease of HSP and a decrease of the velocity of bolus transit inside the pharynx which were particularly marked between the first and the third examination. Manometric examinations of the oro-pharyngeal part of the gastrointestinal tract are useful and supportive methods in the analysis of swallowing disturbances in ALS patients. Full article