The effect of sildenafil on oesophageal motor function in healthy subjects and patients with nutcracker oesophagus

Duodenal acid has been suggested to be of importance for dyspeptic symptoms. We investigated the effects of acid on duodenal mechanosensitivity and antroduodenal motility in 10 healthy subjects before and during duodenal infusion of acid (0.1 N HCl) or water by using a combined barostat-manometry assembly. During acid infusion, increased sensitivity to balloon distension was seen, with reduced perception ( P = 0.04) and discomfort thresholds ( P = 0.06) and higher intensity of discomfort ( P = 0.02) compared with water. Higher balloon volumes were seen during acid infusion, indicating decreased tone ( P = 0.05). Large volume waves were more prevalent during acid than water infusion ( P = 0.009). The acid infusion suppressed antral contractions ( P = 0.04) and increased the number of contractions in the proximal duodenum ( P = 0.02) compared with before the infusion. In conclusion, duodenal acid enhances mechanical sensitivity in the duodenum, affects gastroduodenal motor function, and might be of importance for dyspeptic symptoms.

Download Full-text

Effect of prolonged gastric distension on motor function of LES and of proximal stomach

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00526.2001 ◽

2002 ◽

Vol 283 (3) ◽

pp. G677-G680 ◽

Cited By ~ 8

Author(s):

M. Allocca ◽

M. Mangano ◽

R. Penagini

Keyword(s):

Lower Esophageal Sphincter ◽

Motor Function ◽

Healthy Subjects ◽

Time Effect ◽

Gastric Distension ◽

Threshold Pressure ◽

Proximal Stomach ◽

Experimental Conditions ◽

Esophageal Sphincter ◽

Sensory Functions

Gastric distension is a potent stimulus of transient lower esophageal sphincter (LES) relaxation. To investigate the time effect of prolonged gastric distension on the rate of transient LES relaxations, LES pressure, and the motor and sensory functions of the proximal stomach, we performed a continuous isobaric distension of the proximal stomach at the 75% threshold pressure for discomfort for 2 h in seven healthy subjects. A multilumen assembly incorporating a sleeve and an electronic barostat was used. The rate of transient LES relaxations ( n/30 min) was constant during the first hour [4.1 ± 1.2 (0–30 min) and 5.4 ± 1.1 (30–60 min)] but markedly decreased ( P < 0.05) in the second hour [2.1 ± 0.5 (60–90 min) and 2.3 ± 0.9 (90–120 min)], whereas LES pressure, baseline volume and volume waves within the gastric bag, hunger, and fullness did not change throughout the experiment. It is concluded that the rate of transient LES relaxations decreases with time during prolonged gastric distension, thus suggesting that this type of stimulus should not be used in sequential experimental conditions.

Download Full-text

Quantitative Assessment of Motor Function by an End-Effector Upper Limb Rehabilitation Robot Based on Admittance Control

Applied Sciences ◽

10.3390/app11156854 ◽

2021 ◽

Vol 11 (15) ◽

pp. 6854

Author(s):

Chao Qian ◽

Wei Li ◽

Tianyu Jia ◽

Chong Li ◽

Ping-Ju Lin ◽

...

Keyword(s):

Motor Function ◽

Functional Recovery ◽

Healthy Subjects ◽

Quantitative Assessment ◽

Admittance Control ◽

Stroke Patients ◽

Robot Assisted ◽

Rehabilitation Training ◽

Rehabilitation Robots ◽

Significant Difference

Various rehabilitation robots have been developed to assist the movement training of the upper limbs of stroke patients, among which some have been used to evaluate the motor recovery. However, how to understand the recovery of motor function from the quantitative assessment following robot-assisted rehabilitation training is still not clear. The objective of this study is to propose a quantitative assessment method of motor function based on the force and trajectory characteristics during robotic training to reflect motor functional recovery. To assist stroke patients who are not able to move voluntarily, an assistive training mode was developed for the robot-assisted rehabilitation system based on admittance control. Then, to validate the relationship between characteristic information and functional recovery, a clinical experiment was conducted, in which nine stroke patients and nine healthy subjects were recruited. The results showed a significant difference in movement range and movement smoothness during trajectory tracking tasks between stroke patients and healthy subjects. The two parameters above have a correlation with the Fugl-Meyer Assessment for Upper Extremity (FMU) of the involved patients. The multiple linear regression analysis showed FMU was positively correlated with parameters (R2=0.91,p<0.005). This finding indicated that the above-mentioned method can achieve quantitative assessment of motor function for stroke patients during robot-assisted rehabilitation training, which can contribute to promoting rehabilitation robots in clinical practice.

Download Full-text