Temporal Firing Patterns of Spontaneous Activity For decades, temporal code has been considered as an important mode encoding neural information and evidence for temporal code in the cortex neurons and the receptors i...Temporal Firing Patterns of Spontaneous Activity For decades, temporal code has been considered as an important mode encoding neural information and evidence for temporal code in the cortex neurons and the receptors is growing. However, the basic temporal firing patterns that may constitute to the temporal coding mode and their generating mechanisms in the展开更多
AIM: Sensitization most likely plays an important role in chronic pain disorders, and such sensitization can be mimicked by experimental acid perfusion of the esophagus.The current study systematically investigated th...AIM: Sensitization most likely plays an important role in chronic pain disorders, and such sensitization can be mimicked by experimental acid perfusion of the esophagus.The current study systematically investigated the sensory and motor responses of the esophagus to controlled mechanical stimuli before and after sensitization.METHODS: Thirty healthy subjects were included.Distension of the distal esophagus with a balloon was performed before and after perfusion with 0.1 mol/L hydrochloric acid for 30 min. An impedance planimetry system was used to measure cross-sectional area,volume, pressure, and tension during the distensions. A new model allowed evaluation of the phasic contractions by the tension during contractions as a function of the initial muscle length before the contraction (comparable to the Frank-Starling law for the heart). Length-tension diagrams were used to evaluate the muscle tone before and after relaxation of the smooth muscle with butylscopolamine.RESULTS: The sensitization resulted in allodynia and hyperalgesia to the distension volumes, and the degree of sensitization was related to the infused volume of acid. Furthermore, a nearly 50% increase in the evoked referred pain was seen after sensitization. The mechanical analysis demonstrated hyper-reactivity of the esophagus following acid perfusion, with an increased number and force of the phasic contractions, but the muscle tone did not change.CONCLUSION: Acid perfusion of the esophagus sensitizes the sensory pathways and facilitates secondary contractions.The new model can be used to study abnormal sensorymotor mechanisms in visceral organs.展开更多
AIM： To determine by brain functional magnetic resonance imaging （fMRI） whether cerebral processing of non-visceral stimuli is altered in irritable bowel syndrome （IBS） patients compared with healthy subjects. To...AIM： To determine by brain functional magnetic resonance imaging （fMRI） whether cerebral processing of non-visceral stimuli is altered in irritable bowel syndrome （IBS） patients compared with healthy subjects. To circumvent spinal viscerosomatic convergence mechanisms, we used auditory stimulation, and to identify a possible influence of psychological factors the stimuli differed in their emotional quality. METHODS： In 8 IBS patients and 8 controls, fMRI measurements were performed using a block design of 4 auditory stimuli of different emotional quality （pleasant sounds of chimes, unpleasant peep （2000 Hz）, neutral words, and emotional words）. A gradient echo T2＊weighted sequence was used for the functional scans. Statistical maps were constructed using the general linear model. RESULTS： To emotional auditory stimuli, IBS patients relative to controls responded with stronger deactivations in a greater variety of emotional processing regions, while the response patterns, unlike in controls, did not differentiate between distressing or pleasant sounds. To neutral auditory stimuli, by contrast, only IBS patients responded with large significant activations. CONCLUSION： Altered cerebral response patterns to auditory stimuli in emotional stimulus-processing regions suggest that altered sensory processing in IBS may not be specific for visceral sensation, but might reflect generalized changes in emotional sensitivity and affectire reactivity, possibly associated with the psychological comorbidity often found in IBS patients.展开更多
Mucosal adaptation is an essential process in gut ho- meostasis. The intestinal mucosa adapts to a range of pathological conditions including starvation, short-gut syndrome, obesity, and bariatric surgery. Broadly, th...Mucosal adaptation is an essential process in gut ho- meostasis. The intestinal mucosa adapts to a range of pathological conditions including starvation, short-gut syndrome, obesity, and bariatric surgery. Broadly, these adaptive functions can be grouped into proliferation and differentiation. These are influenced by diverse interactions with hormonal, immune, dietary, nervous, and mechanical stimuli. It seems likely that clinical out- comes can be improved by manipulating the physiol- ogy of adaptation. This review will summarize current understanding of the basic science surrounding adapta- tion, delineate the wide range of potential targets for therapeutic intervention, and discuss how these might be incorporated into an overall treatment plan. Deeper insight into the physiologic basis of adaptation will identify further targets for intervention to improve clini- cal outcomes.展开更多
文摘Temporal Firing Patterns of Spontaneous Activity For decades, temporal code has been considered as an important mode encoding neural information and evidence for temporal code in the cortex neurons and the receptors is growing. However, the basic temporal firing patterns that may constitute to the temporal coding mode and their generating mechanisms in the
基金Supported by the "Det Obelske Familifond", "Spar Nord Fonden"and the Danish Technical Research Council
文摘AIM: Sensitization most likely plays an important role in chronic pain disorders, and such sensitization can be mimicked by experimental acid perfusion of the esophagus.The current study systematically investigated the sensory and motor responses of the esophagus to controlled mechanical stimuli before and after sensitization.METHODS: Thirty healthy subjects were included.Distension of the distal esophagus with a balloon was performed before and after perfusion with 0.1 mol/L hydrochloric acid for 30 min. An impedance planimetry system was used to measure cross-sectional area,volume, pressure, and tension during the distensions. A new model allowed evaluation of the phasic contractions by the tension during contractions as a function of the initial muscle length before the contraction (comparable to the Frank-Starling law for the heart). Length-tension diagrams were used to evaluate the muscle tone before and after relaxation of the smooth muscle with butylscopolamine.RESULTS: The sensitization resulted in allodynia and hyperalgesia to the distension volumes, and the degree of sensitization was related to the infused volume of acid. Furthermore, a nearly 50% increase in the evoked referred pain was seen after sensitization. The mechanical analysis demonstrated hyper-reactivity of the esophagus following acid perfusion, with an increased number and force of the phasic contractions, but the muscle tone did not change.CONCLUSION: Acid perfusion of the esophagus sensitizes the sensory pathways and facilitates secondary contractions.The new model can be used to study abnormal sensorymotor mechanisms in visceral organs.
文摘AIM： To determine by brain functional magnetic resonance imaging （fMRI） whether cerebral processing of non-visceral stimuli is altered in irritable bowel syndrome （IBS） patients compared with healthy subjects. To circumvent spinal viscerosomatic convergence mechanisms, we used auditory stimulation, and to identify a possible influence of psychological factors the stimuli differed in their emotional quality. METHODS： In 8 IBS patients and 8 controls, fMRI measurements were performed using a block design of 4 auditory stimuli of different emotional quality （pleasant sounds of chimes, unpleasant peep （2000 Hz）, neutral words, and emotional words）. A gradient echo T2＊weighted sequence was used for the functional scans. Statistical maps were constructed using the general linear model. RESULTS： To emotional auditory stimuli, IBS patients relative to controls responded with stronger deactivations in a greater variety of emotional processing regions, while the response patterns, unlike in controls, did not differentiate between distressing or pleasant sounds. To neutral auditory stimuli, by contrast, only IBS patients responded with large significant activations. CONCLUSION： Altered cerebral response patterns to auditory stimuli in emotional stimulus-processing regions suggest that altered sensory processing in IBS may not be specific for visceral sensation, but might reflect generalized changes in emotional sensitivity and affectire reactivity, possibly associated with the psychological comorbidity often found in IBS patients.
文摘Mucosal adaptation is an essential process in gut ho- meostasis. The intestinal mucosa adapts to a range of pathological conditions including starvation, short-gut syndrome, obesity, and bariatric surgery. Broadly, these adaptive functions can be grouped into proliferation and differentiation. These are influenced by diverse interactions with hormonal, immune, dietary, nervous, and mechanical stimuli. It seems likely that clinical out- comes can be improved by manipulating the physiol- ogy of adaptation. This review will summarize current understanding of the basic science surrounding adapta- tion, delineate the wide range of potential targets for therapeutic intervention, and discuss how these might be incorporated into an overall treatment plan. Deeper insight into the physiologic basis of adaptation will identify further targets for intervention to improve clini- cal outcomes.
