Achalasia cardia is one of the common causes of motor dysphagia.Though the disease was first described more than 300 years ago,exact pathogenesis of this condition still remains enigmatic.Pathophysiologically,achalasi...Achalasia cardia is one of the common causes of motor dysphagia.Though the disease was first described more than 300 years ago,exact pathogenesis of this condition still remains enigmatic.Pathophysiologically,achalasia cardia is caused by loss of inhibitory ganglion in the myenteric plexus of the esophagus.In the initial stage,degeneration of inhibitory nerves in the esophagus results in unopposed action of excitatory neurotransmitters such as acetylcholine,resulting in high amplitude non-peristaltic contractions(vigorous achalasia);progressive loss of cholinergic neurons over time results in dilation and low amplitude simultaneous contractions in the esophageal body(classic achalasia).Since the initial description,several studies have attempted to explore initiating agents that may cause the disease,such as viral infection,other environmental factors,autoimmunity,and genetic factors.Though Chagas disease,which mimics achalasia,is caused by an infective agent,available evidence suggests that infection may not be an independent cause of primary achalasia.A genetic basis for achalasia is supported by reports showing occurrence of disease in monozygotic twins,siblings and other first-degree relatives and occurrence in association with other genetic diseases such as Down's syndrome and Parkinson's disease.Polymorphisms in genes encoding for nitric oxide synthase,receptors for vasoactive intestinal peptide,interleukin 23 and the ALADIN gene have been reported.However,studies on larger numbers of patients and controls from different ethnic groups are needed before definite conclusions can be obtained.Currently,the disease is believed to be multi-factorial,with autoimmune mechanisms triggered by infection in a genetically predisposed individual leading to degeneration of inhibitory ganglia in the wall of the esophagus.展开更多
MOST cases of encephalitis are caused by viruses but a few have an immunological basis, such as paraneoplastic encephalitis, with specific antibodies identified. One recently characterized encephalitis caused by antib...MOST cases of encephalitis are caused by viruses but a few have an immunological basis, such as paraneoplastic encephalitis, with specific antibodies identified. One recently characterized encephalitis caused by antibodies is anti-N- methyl-D-aspartate （NMDA） receptor encephalitis. It is a form of paraneoplastic limbic encephalitis associated with ovarian teratoma and has recently been described.The NMDA receptor mediates excitatory neurotransmission. It is important for synaptic plasticity, and thus for higher function such as learning and memory. This disorder results in prominent psychiatric symptoms followed by a rapid decline of the level of consciousness, central hypoventilation, seizures, involuntary movements and dysautonomia.展开更多
AIM: To investigate whether the combined methods of unilateral thyroparathyroidectomy (TPX) and subdiaphragmatic vagotomy (VAX) can be adapted for rats and used as a reliable method to produce a rat model of long-term...AIM: To investigate whether the combined methods of unilateral thyroparathyroidectomy (TPX) and subdiaphragmatic vagotomy (VAX) can be adapted for rats and used as a reliable method to produce a rat model of long-term reduction of gastrointestinal (GI) motor function. METHODS: Male Sprague-Dawley rats were randomly divided into 3 groups, normal, sham-operated and unilateral TPX plus VAX. The TPX plus VAX rats received VAX 7 d after application of TPX, and dietary intake and fecal output were then measured daily for 1 wk.After completion of the experiments, gastric emptying and small bowel transit were measured in vivo, and the contractile responses of colonic strips to excitatory and inhibitory neurotransmitters were estimated using isometric force transducers in vitro. RESULTS: In comparison with normal and sham-operated rats, rats which received unilateral TPX plus VAX showed a significant decrease in body weight and in fecal pellet number and weight throughout the entire week. Application of TPX plus VAX to rats markedly delayed gastric emptying and small bowel transit. In TPX plus VAX rats, the longitudinal muscles of the proximal colon showed a significant reduction in contractile responses to acetylcholine (5 × 10-6 mol/L), and a dramatic attenuation of contractile responses was also observed in both the longitudinal and circular muscles of the distal colon. However, the spontaneous contractility of the colonic strips from TPX plus VAX rats was not significantly affected by treatment with N-nitro-Larginine-methyl ester (0.1 mol/L). CONCLUSION: The results indicate that unilateral TPX plus VAX reduced the motor function of the GI tract in rats, and the reduced gut motility is likely mediated, at least in part, by inhibition of the excitatory neurotransmitter system.展开更多
文摘Achalasia cardia is one of the common causes of motor dysphagia.Though the disease was first described more than 300 years ago,exact pathogenesis of this condition still remains enigmatic.Pathophysiologically,achalasia cardia is caused by loss of inhibitory ganglion in the myenteric plexus of the esophagus.In the initial stage,degeneration of inhibitory nerves in the esophagus results in unopposed action of excitatory neurotransmitters such as acetylcholine,resulting in high amplitude non-peristaltic contractions(vigorous achalasia);progressive loss of cholinergic neurons over time results in dilation and low amplitude simultaneous contractions in the esophageal body(classic achalasia).Since the initial description,several studies have attempted to explore initiating agents that may cause the disease,such as viral infection,other environmental factors,autoimmunity,and genetic factors.Though Chagas disease,which mimics achalasia,is caused by an infective agent,available evidence suggests that infection may not be an independent cause of primary achalasia.A genetic basis for achalasia is supported by reports showing occurrence of disease in monozygotic twins,siblings and other first-degree relatives and occurrence in association with other genetic diseases such as Down's syndrome and Parkinson's disease.Polymorphisms in genes encoding for nitric oxide synthase,receptors for vasoactive intestinal peptide,interleukin 23 and the ALADIN gene have been reported.However,studies on larger numbers of patients and controls from different ethnic groups are needed before definite conclusions can be obtained.Currently,the disease is believed to be multi-factorial,with autoimmune mechanisms triggered by infection in a genetically predisposed individual leading to degeneration of inhibitory ganglia in the wall of the esophagus.
文摘MOST cases of encephalitis are caused by viruses but a few have an immunological basis, such as paraneoplastic encephalitis, with specific antibodies identified. One recently characterized encephalitis caused by antibodies is anti-N- methyl-D-aspartate （NMDA） receptor encephalitis. It is a form of paraneoplastic limbic encephalitis associated with ovarian teratoma and has recently been described.The NMDA receptor mediates excitatory neurotransmission. It is important for synaptic plasticity, and thus for higher function such as learning and memory. This disorder results in prominent psychiatric symptoms followed by a rapid decline of the level of consciousness, central hypoventilation, seizures, involuntary movements and dysautonomia.
基金Grants of the Korea Healthcare Technology Rand D Project, Ministry of Health, Welfare and Family AffairsA090216the National Research Foundation of Korea2011-0014777
文摘AIM: To investigate whether the combined methods of unilateral thyroparathyroidectomy (TPX) and subdiaphragmatic vagotomy (VAX) can be adapted for rats and used as a reliable method to produce a rat model of long-term reduction of gastrointestinal (GI) motor function. METHODS: Male Sprague-Dawley rats were randomly divided into 3 groups, normal, sham-operated and unilateral TPX plus VAX. The TPX plus VAX rats received VAX 7 d after application of TPX, and dietary intake and fecal output were then measured daily for 1 wk.After completion of the experiments, gastric emptying and small bowel transit were measured in vivo, and the contractile responses of colonic strips to excitatory and inhibitory neurotransmitters were estimated using isometric force transducers in vitro. RESULTS: In comparison with normal and sham-operated rats, rats which received unilateral TPX plus VAX showed a significant decrease in body weight and in fecal pellet number and weight throughout the entire week. Application of TPX plus VAX to rats markedly delayed gastric emptying and small bowel transit. In TPX plus VAX rats, the longitudinal muscles of the proximal colon showed a significant reduction in contractile responses to acetylcholine (5 × 10-6 mol/L), and a dramatic attenuation of contractile responses was also observed in both the longitudinal and circular muscles of the distal colon. However, the spontaneous contractility of the colonic strips from TPX plus VAX rats was not significantly affected by treatment with N-nitro-Larginine-methyl ester (0.1 mol/L). CONCLUSION: The results indicate that unilateral TPX plus VAX reduced the motor function of the GI tract in rats, and the reduced gut motility is likely mediated, at least in part, by inhibition of the excitatory neurotransmitter system.
