Meconium-related ileus in extremely low-birthweight neonates: etiological considerations from histology and radiology.

BACKGROUND: A nationwide survey on neonatal surgery conducted by the Japanese Society of Pediatric Surgeons has demonstrated that the mortality of neonatal intestinal perforation has risen over the past 15 years. The incidence of intestinal perforation in extremely low-birthweight (ELBW) neonates has been increasing as more ELBW neonates survive and as the live-birth rate of ELBW has increased. In contrast to necrotizing enterocolitis (NEC) and focal intestinal perforation (FIP), the pathogenesis of meconium-related ileus, defined as functional bowel obstruction characterized by delayed meconium excretion and microcolon, remains unclarified. METHODS: The histology of 13 ELBW neonates with intestinal perforation secondary to meconium-related ileus was reviewed, and the radiology of 33 cases of meconium-related ileus diagnosed on contrast enema was reviewed. Specimens obtained from 16 ELBW neonates without gastrointestinal disease served as age-matched controls for histological assessment. RESULTS: The size of the ganglion cell nucleus in meconium-related ileus and in control subjects was 47.3 ± 22.0 µm(2) and 37.8 ± 11.6 µm(2), respectively, which was not significantly different. In all cases of meconium-related ileus, contrast enema demonstrated a microcolon or small-sized colon, with a gradual caliber change in the ileum and filling defects due to meconium in the ileum or colon, showing not-identical locations of caliber changes and filling defects. CONCLUSION: Morphological immaturity of ganglia was not suggested to be the pathogenesis of meconium-related ileus. Impaction of inspissated meconium is not the cause of obstruction, but the result of excessive water absorption in the hypoperistaltic bowel before birth, although the underlying mechanism responsible for the fetal hypoperistalsis remains unclear.

Neuroanatomical basis of acupuncture treatment for some common illnesses.

The acupuncture treatment formulae for some common conditions are reviewed. These conditions include low back pain, sciatica, trigeminal neuralgia, facial nerve palsy, asthma, nausea and vomiting, gastritis and dysmenorrhoea. It is found that in many cases, the acupuncture points traditionally used for the treatment have a neuroanatomical significance from the viewpoint of Western medicine. And from that one can hypothesise a plausible mechanism of action as to how acupuncture achieves its therapeutic effects in terms of contemporary Western medicine. These mechanisms of action include intramuscular stimulation for treating muscular pain and nerve stimulation for treating neuropathies. The sympathetic ganglion may be involved in the acupuncture treatment of asthma. Somato-autonomic reflex may be responsible for the acupuncture effect on gastritis.

Horner's syndrome: a complication of experimental carotid artery surgery in rats.

PURPOSE: To report on the occurrence of iatrogenic Horner's syndrome (HS) in epileptic rats after implantation of an electrode for vagus nerve stimulation and to describe the possible consequences of this new complication of carotid artery surgery in rats. METHODS: A bipolar circular electrode was placed around the left carotid artery and vagus nerve of 31 rats. The incidence of HS was evaluated by visual inspection within 24 h after surgery. RESULTS: 68% of rats suffered from HS immediately after surgery. This complication did not affect epileptogenesis. CONCLUSION: The occurrence of HS in the rat is a frequent complication of vagus nerve electrode implantation, which does not affect epileptogenesis in this study. However, rats affected by HS may suffer from damage to the sympathetic innervation of the gut, due to rat-specific neuroanatomy. Therefore, caution towards other research questions is warranted.

Low-frequency electroacupuncture suppresses carrageenan-induced paw inflammation in mice via sympathetic post-ganglionic neurons, while high-frequency EA suppression is mediated by the sympathoadrenal medullary axis.

Although the frequency-dependent antinociceptive mechanisms of electroacupuncture (EA) have been well demonstrated, the anti-inflammatory mechanisms that underlie the suppressive effects induced by different frequencies of EA stimulation on peripheral inflammation are largely unknown. We have previously reported that EA stimulation can activate the sympathetic nervous system (SNS) and that this activation is responsible for the EA-induced suppression of zymosan-induced leukocyte migration. The present study was designed to evaluate the differential effect of low (1Hz, LF EA) versus high (120Hz, HF EA) frequency EA stimulation on SNS activation and ultimately on carrageenan-induced inflammation. Immediately after carrageenan injection, we applied either LF EA or HF EA bilaterally to the Zusanli (ST36) acupoints. To evaluate the anti-inflammatory effect of EA (EA-AI), paw volume and myeloperoxidase (MPO) activity, a marker of infiltrated leukocytes, were measured and the paw withdrawal latency to noxious heat stimulation was also assessed. Both LF EA and HF EA significantly suppressed the carrageenan-induced paw edema and MPO activity. Moreover, thermal hyperalgesia was strongly attenuated in both the LF EA and HF EA groups. Adrenalectomy significantly diminished HF EA-AI without affecting LF EA-AI. Pretreatment with the corticosterone receptor antagonist, RU-486 did not affect either LF EA- or HF EA-AI. On the other hand, administration of 6-hydroxydopamine (a neurotoxin for peripheral sympathetic nerve endings) selectively blocked LF EA-AI. Propranolol (a beta-adrenoceptor antagonist) completely abolished both LF EA- and HF EA-AI. The results of this study suggest that the suppressive effects of LF EA on carrageenan-induced paw inflammation are mediated by sympathetic post-ganglionic neurons, while the suppressive effects of HF EA are mediated by the sympatho-adrenal medullary axis.

Awake one stage bilateral thoracoscopic sympathectomy for palmar hyperhidrosis: a safe outpatient procedure.

OBJECTIVE: To verify the feasibility and compare the results of thoracoscopic sympathectomy under local anaesthesia (LA) and spontaneous breathing vs. general anaesthesia (GA) with one-lung ventilation. METHODS: Two groups of consecutive patients underwent one stage bilateral T2-T3 thoracoscopic sympathectomy under LA (n=15) and GA (n=30) by the same surgical team for treatment of primary palmar hyperhidrosis. The groups were homogeneous for relevant demographic, physiological and clinical data, including pulmonary function. In both groups, patient's satisfaction was evaluated 24h after surgery by a simple interview and scored into five grades (1=very poor to 5=excellent), while quality of life (QOL) was evaluated by SF-36 and Nottingham's Health Profile questionnaires before and 6 months after surgery. A cost comparison between groups concerning devices, drugs, global in operating room time, medical personnel and hospital stay was also carried out. RESULTS: No operative mortality was recorded. The overall in operating room time for the whole bilateral procedure under LA was 63.55+/-10.58 vs. 86.05+/-5.75 under GA (P<0.01) and temperature increased in all patients from a baseline of 25.42+/-0.56 up to 32.15+/-0.84 degrees C. All patients undergone LA were discharged the same day after a chest roentgenogram and a short stay in the outpatient clinic. Among them three patients (20%) experienced a minimal (<30%) pneumothorax that required no treatment, while five (33.3%) had a trunk compensatory sweating that spontaneously resolved on the long run. Patients undergoing GA were discharged after a mean stay of 1.38+/-0.6 days. Among these, eight (26.6%) had prolonged trunk compensatory sweating that did not persist longer than 3 months. At a follow-up of 7.16+/-2.97 months, QOL was significantly improved with no difference between groups. The overall rate of satisfaction was greater in the LA group (P<0.05). CONCLUSIONS: In our study, awake one stage bilateral thoracoscopic sympathectomy for palmar hyperhidrosis could be safely and effectively performed as an outpatient procedure in patients refusing GA. Postoperative quality of life was equal to that in patients undergone the same procedure under GA, while patient satisfaction was better and cost were significantly reduced.

Ultrashort Hirschsprung's disease: myth or reality.

The term ultrashort Hirschsprung's disease has been used to define a spectrum of conditions with clinical presentation similar to Hirschsprung's disease but with presence of ganglion cells on rectal biopsy. In contrast to Hirschsprung's disease, there is no transition zone on barium enema. However, as in classical Hirschsprung's disease, there is no reflex internal sphincter relaxation on rectal manometry. We reviewed the presentation of five patients with chronic constipation who fulfilled the criteria for ultrashort Hirschsprung's disease. After positive anorectal manometry, despite the presence of ganglion cells on suction rectal biopsy, internal sphincter myomectomy was performed in four patients. Resolution of symptoms was noted in all operated patients. Normal ganglion cells were present throughout the entire length of all myomectomy specimens. There is controversy in the literature concerning the diagnosis of ultrashort Hirschsprung's disease. Most of the confusion concerns whether a short segment of aganglionosis proximal to the dentate line is permissible for the diagnosis of ultrashort Hirschsprung's disease and to what extent such aganglionosis is physiological. Perhaps it would be more accurate to define this entity by the presence of ganglion cells on rectal biopsy as well as the failure of the internal sphincter to relax on rectal manometry and to describe it as anorectal achalasia in severely constipated patients.

Changes in neural and humoral mechanisms of the heart in sudden death due to myocardial abnormalities.

Quantitative neurohistochemical study of adrenergic elements of the myocardium and the adrenal medulla in victims of sudden death revealed an unequal and focal depletion of catecholamines attributable to prior pathologic processes in the myocardium. The greatest changes in cardiac innervation were found in cases of acute myocardial infarction and alcoholic cardiomyopathy, and the adrenergic plexuses were better preserved in cases of coronary heart disease without focal myocardial changes. Ultrastructural study of cardiac innervation in patients who died suddenly showed more pronounced changes in the nerve plexuses of the sinus node than in the perinodal nerves of the working myocardium. The changes in coronary artery innervation were usually related to the severity of stenosis due to fibrous plaque; desympathization of the vessels and the adjoining myocardial zone was also found in cases with 50% or greater occlusion of the lumen. The bulk of chromaffinocytes were depleted and weakly luminescent in the adrenal glands of patients with acute myocardial infarction who died suddenly. In contrast, chromaffinocytes with moderate and bright luminescence were prevalent in cases of sudden death with scarring from previous myocardial infarction and with alcoholic cardiomyopathy. Ultrastructural and histochemical examinations demonstrated that changes in the neurons of sympathetic ganglia increased with more severe atherosclerotic lesions of the aorta and with greater changes in the vessels supplying the ganglia. In experiments on rabbits and dogs, both coronary artery ligation and electrostimulation produced cardiac fibrillation followed by a local increase in luminescence intensity of the myocardial nerve plexuses when their density remained high. Chemoreceptors located along the coronary vessels and pulmonary artery in dogs included small cells with bright fluorescence and adrenergic nerve fibers.