The time sequence of injury and recovery following transient reversible intestinal ischemia

Intestinal mucosal damage and regeneration were examined in rats following transient ischemia produced by the occlusion of the superior mesenteric artery for 30 min. Animal groups were assigned for harvesting of small bowel specimens at 10, 17, and 30 min and 1, 2, 3, 4, 6, 12, and 24 hr post-relief of ischemia. Severe damage to the villi was evident already at 10 min postischemia. Thereafter a very rapid restitutional process was observed with restoration of villi epithelium in 47.6% of the examined animals at 60 min, 75% at 4 hr, and 100% at 12 hr. This rapid sequence of events should be taken into consideration when designing experimental ischemic bowel animal models and possible therapeutic modalities.

A simple and rapid method for staining the enteric ganglia: application for Hirschsprung's disease

A simple and reliable method is described for staining the nerve plexuses of the human gastrointestinal tract in whole-mounts. The staining does not require fixation and consists of a single step of 6 to 10 minutes incubation in a solution of the fluorescent dye 4-(4-diethylaminostyryl)-methylpyridinium iodide. Aganglionic bowel specimens from 6 patients with Hirschsprung's disease were stained by this method and displayed the absence of ganglion cells and an abundance of nerve fibers in the myenteric and submucosal plexuses. This staining may be suitable for the diagnosis of Hirschsprung's disease.

[Spontaneous splenic rupture associated with facial erysipelas]

Spontaneous rupture of the spleen is rare Although over 100 cases have been reported, only a few were of true spontaneous rupture. Most cases were associated with diseases which directly involved the spleen. We report a 53-year-old woman with facial erysipelas and true spontaneous rupture of the spleen.

Nissen fundoplication in the treatment of children with familial dysautonomia

Thirty-four children with familial dysautonomia (FD) underwent Nissen fundoplication and gastrostomy. The indications for operation were persistent cyclic vomiting that resulted in repeated aspiration pneumonia (94% of the patients), chronic dehydration (82%), failure to thrive (97%), and frequent hospitalizations (76%). There was no operative or early postoperative mortality. Long-term follow-up for up to 12 years was available. Eight patients died during this period from 7 months to 7.5 years postoperatively. In 5 patients (15% of the operated patients), the fundoplication ceased to function 16 months to 5 years postoperatively, which was attributed mainly to repeated severe dysautonomic crises with vigorous retching. Vomiting ceased in 85% of the symptomatic patients; pulmonary deterioration was halted, and the frequency of aspiration pneumonia was reduced in 68%; nutritional improvement was seen in 44%; the hydration status improved in 88%; and the frequency of hospital admissions decreased in 74%. These long-term findings resulted in a significant improvement in the quality of life for the majority of the patients. The absence of operative mortality and the low postoperative morbidity, together with the long-term beneficial results of this surgical procedure, should encourage early surgical intervention in selected FD patients.

Eicosanoids in hypoxic insult to neonatal rabbit bowel

Eicosanoids, derivatives of arachidonic acid, play a role in several inflammatory diseases of the bowel. To determine whether prostaglandin E2 (PGE2), leukotriene B4 (LTB4), and leukotriene C4D4E4 (LTC4D4E4), have a role in hypoxic insult to the intestine, we examined the levels of these mediators in a hypoxic neonatal rabbit model. One group of animals underwent hypoxic insult postnatally, the second group did not undergo hypoxia and served as a control. The levels of PGE2, LTB4, and LTC4D4E4 were determined by radioimmunoassay. PGE2 in the hypoxic group was 1,779 +/- 142 pg/mg protein (mean +/- SD) as opposed to 2,380 +/- 197 pg/mg protein in the control group (p less than 0.02). LTB4 level was 5,446 +/- 3,492 pg/mg protein in the hypoxic rabbits and 3,362 +/- 2,570 pg/mg protein in the control group (p less than 0.03). There was no statistically significant difference in the level of LTC4D4E4 between the two groups. Our study shows that hypoxia shifts the arachidonic acid metabolism toward enhanced lipoxygenase activity with a resultant increase in LTB4 levels and a concomitant decrease in cyclooxygenase activity with reduced PGE2 levels in the bowel. The shift in the balance between these eicosanoids may play a role in the pathogenesis of ischemic-hypoxic bowel diseases by enhancing the inflammatory response in the intestine, and simultaneously, diminishing cytoprotection.

Acquired tracheoesophageal fistula in infancy and childhood

Acquired tracheoesophageal fistula (TEF) is a rare entity in the pediatric age group. We report two pediatric patients with acquired TEF caused by shells of pistachio nuts. In both patients the primary operation did not resolve the problem and a second intervention for recurrent fistula was needed. The special nature of acquired TEF, particularly the one described herein, requires delayed surgical intervention and meticulous separation of the respiratory and alimentary tracts by an intercostal muscle flap.

Mechanistic aspects of 1-methyl-4-phenyl pyridinium iodide toxicity in Escherichia coli: the role of oxygen and hydrogen peroxide

1-Methyl-4-phenyl pyridinium iodide (MPP+) and paraquat (PQ+2) are two structurally analogous and highly toxic pyridinium compounds. The mechanism of PQ+2 toxicity is best understood in the bacterial model system. While numerous studies in a variety of systems have indicated the causative role of free radicals and other oxygen-derived active species in PQ+2 toxicity, this question is yet unresolved in the case of MPP+. In this study we have used the Escherichia coli model and demonstrated that MPP+ is toxic to bacterial cells in dose- and time-dependent modes. Additionally, it is shown that only in the presence of molecular oxygen did bacterial inactivation occur. This requirement for oxygen can be circumvented by adventitious H2O2. The protective effects of the chemical scavenger--mannitol--and of histidine are presented. These results are in complete accord with a free radical mechanism for MPP+ toxicity.

Salicylate as an in vivo free radical trap: studies on ischemic insult to the rat intestine

Ischemia of rat intestine was induced in vivo by occlusion of the superior mesenteric artery (SMA) for 15 min. Sodium salicylate, 100 mg/kg, given IP, 30 min prior to the ischemic event served as a specific trap for hydroxyl radicals. Portions of the bowel were sequentially isolated and removed--2 min prior to ischemia, 2 min prior to declamping of the SMA, and 10 min following reperfusion. The bowel segments were homogenized in 3% TCA. The homogenate was centrifuged and filtrated through a 0.22 mu filter. The hydroxylation products of salicylate, dihydroxybenzoic acid (DHBA) derivatives, were isolated, identified, and quantified by HPLC coupled with electrochemical detection (ECD). The level of 2,5-DHBA (M +/- SE, ng/g tissue) in the preischemic bowel (N = 21) was 241.8 +/- 10.0. In the ischemic specimen the level of 2,5-DHBA increased significantly to 313.3 +/- 15.5 (p = 0.0129), and remained unchanged in the reperfusion period (322.8 +/- 15.5). The histological examination correlated well with these levels: mild villi damage in the ischemic period with no further exacerbation during the reperfusion period. This study in an in vivo animal model of intestinal ischemia-reperfusion provides direct evidence for the involvement of free radicals during the ischemic insult.

Direct evidence for the involvement of free radicals in ischemic insult to the intestine

Ischemia of rat intestine was induced in vivo by occlusion of the superior mesenteric artery (SMA) for 15 min. Sodium salicylate, 100 mg/kg, given IP, 30 min prior to the ischemic event served as a specific trap for hydroxyl radicals and provided direct evidence for the involvement of free radicals during the ischemic insult. Portions of the bowel were sequentially isolated and removed. The hydroxylation products, dihydroxybenzoic acid (DHBA) derivatives were isolated, identified and quantified by HPLC coupled with electrochemical detection (ECD). The level of 2,5-DHBA (Mean +/- SE, ng/g tissue) in the preischemic bowel (N = 21) was 241.8 +/- 10.0. It rose significantly to 313.3 +/- 15.5 in the ischemic specimen (p = 0.0129) and remained unchanged in the reperfusion period (322.8 +/- 15.5). The histological examination correlated well with these levels: mild villi damage in the ischemic period with no further damage in the reperfusion period.

Long-term evaluation of a new selectively biodegradable vascular graft coated with polyethylene oxide-polylactic acid for right ventricular conduit. An experimental study

Low-porosity woven Dacron grafts have been used extensively as an extracardiac conduit in the surgical treatment of congenital and acquired heart diseases involving total heparinization. Caution is still warranted in their use, however, because of long-term complications, including calcification and development of obstructive fibrous peel. In contrast, high-porosity grafts offer much better tissue anchorage and healing but cannot be used under heparinization. We have developed a compound vascular prosthesis in which a knitted Dacron graft is coated with a polymeric biodegradable sealant. Polyethylene oxide-polylactic acid-segmented copolymers comprised the degradable component of the graft. In vitro studies showed that the coated prosthesis exhibited a highly flexible elastomer-like mechanical response. The prostheses were completely watertight, and significant degradation started after 1 week, with absorption completed after 3 weeks. Seven woven and six knitted polyethylene oxide-polylactic acid-coated Dacron grafts used as extracordiac conduits (16 mm), connecting the right ventricle and the pulmonary artery were implanted in dogs. The dogs were killed after 12 to 18 months, and the results are reported. Scanning electron microscopy examination showed peel detachment and nonhomogenous intimal surface with fenestrations in the woven graft group, but complete healing and incorporation of the pseudointima with homogenous, thin lining of the luminal surface in the polyethylene oxide-polylactic acid-coated group. Histologic studies indicated much superior healing and anchorage of the periprosthetic tissue and the pseudointima in the polyethylene oxide-polylactic acid-coated grafts. The biodegradable polymer was fully degraded and exhibited a complete incorporation of the compound vascular prosthesis. This study indicates the superior healing properties of these selectively biodegradable grafts, which might increase long-term patency and decrease complications of right ventricular conduits.

[Congenital diaphragmatic hernia presenting after the neonatal period]

Congenital diaphragmatic hernia (Bochdalek) is a congenital malformation usually presenting early after birth with a mortality of 50-70%. It is rarely diagnosed after the neonatal period, when the prognosis is considered favorable. We operated on 11 children past the neonatal period, ranging from 6 months to 5.5 years of age. 9 had presented with respiratory symptoms and were operated on semi-electively with excellent results. 2, operated on for strangulation of bowel incarcerated in the hernia, eventually died (aged 7 months and 1 year, respectively). Early diagnosis is important, as early surgery is recommended, even in those without symptoms.

[Physiological responses to heat and effort and complaints of hyperperspiration]

The sensation of hyperperspiration is a common complaint in hot, humid climates. 54 men and 20 women, 18-47 years old, who had this complaint and 27 male control subjects were examined at rest and after 1 hour of mild exercise (40W) under conditions of heat stress (37 degrees C, 50% relative humidity). During exposure to heat rectal and skin temperatures and heart rate were measured every 15 min. Sweat rate was calculated for the entire period of exposure and sweat gland density was measured at 0, 60 and 120 min. Only insignificant deviations from baseline values were noted at rest. During exercise the sweat rate of the men with the complaint was within normal limits and similar to that of the control men (285 +/- 75 ml/m2 vs 272 +/- 48). Matching for age and V02 max revealed no significant differences in physiological responses of men with and those without the complaint. Women with the complaint lost 25-30% less fluid (226 +/- 67 ml/m2) and their concentrations of active sweat glands were lower than in either of the male groups. 2 men and 1 woman with the complaint and 1 control lost 400-425 ml/m2 during exercise, the upper limit of normal. Only 1 subject showed hyperperspiration (855 ml/m2) during the test. All physiological parameters examined in these 5 subjects were within normal limits. It is concluded that the complaint of hyperperspiration in our self-selected group is basically a subjective feeling and has no pathological basis. None of the subjects was heat intolerant.

Peritonitis and empyema following the use of dextran in tubal operations

Two patients developed severe bacterial sepsis with peritonitis and pleural empyema following tubal surgery. Intraperitoneal low-molecular dextran was used in both patients and hydrocortisone was administered perioperatively. The use of dextran in tubal surgery probably increases the risk of severe postoperative infection and should be avoided in susceptible patients. Prophylactic antibiotics may be indicated when dextran is administered.

Gallbladder distention in premature neonates receiving parenteral nutrition

Contraction of the gallbladder is mediated through the release of cholecystokinin from duodenal cells secondary to enteral feedings. Premature infants are often nourished by parenteral hyperalimentation leading to prolonged inactivation of the gallbladder. Such inactivation probably accounts for the increased incidence of gallbladder distention observed in premature neonates. Two cases of premature infants are described in whom distention of the gallbladder occurred during parenteral hyperalimentation. The distention resolved spontaneously secondary to the introduction of enteral feedings. A trial period of oral or tube feeding is recommended in such cases prior to any attempt to release the distention by a surgical intervention.

Ring 18 chromosome with mental retardation, hemidysmorphism, and mitochondrial encephalomyopathy

A 2 1/2-year-old female is reported with ring 18 chromosome syndrome. The chromosomal abnormality was found in all examined leukocytes and cultured skin fibroblasts. Besides the usual clinical characteristics of this syndrome, two additional features are described that have not been reported previously: right hemidysmorphism, including hypertrophy of the tongue and lower extremity; coloboma of the lower right side of the gums; atretic external right ear canal; and hypotonia with mitochondrial encephalomyopathy associated with excessive ketonemia during normal food intake and a large increase after overnight fast.

Multiple gastrointestinal atresias with intraluminal calcifications

A case is reported of multiple atresia of the entire gastrointestinal tract, extending from the stomach to the distal colon. The defect is rare and no survivors have been reported.

Gastrointestinal perforations in the neonatal period

Forty-eight neonates were treated for gastrointestinal perforation during a 9-year period. In 30, perforation occurred within the first week of life. Thirty-six were preterm infants and many had a history of obstetric and postnatal complications. Perforation resulted from necrotizing enterocolitis in 26 patients, whereas in 14 neonates spontaneous perforation occurred in an apparently normal bowel, with no evident cause (idiopathic perforation). In 6 patients perforation was associated with meconium ileus. Primary closure was carried out for perforations of the duodenum and stomach. Intestinal perforations were usually treated by resection and enterostomies. The overall mortality rate in this series was 46%. The highest mortality rate was associated with necrotizing enterocolitis (62%). The mortality rate was only 14% in patients with idiopathic perforation. Despite improvement in the prognosis of neonatal gastrointestinal perforations in recent years, it is still discouraging, reflecting the difficulty in preventing and treating necrotizing enterocolitis.

Idiopathic gastrointestinal perforation in the neonate

Spontaneous localized perforation of the gastrointestinal tract, unrelated to mechanical intestinal obstruction and with no evidence of necrotizing entrocolitis (NEC), occurred in 20 neonates. Three perforations were located in the stomach, 11 in the small intestine, and six in the colon. Maternal obstetric complications as well as prematurity and postnatal distress were common in these patients. The overall survival rate was 80%. There was no late gastrointestinal symptoms in the survivors. Whether idiopathic perforation of the gastrointestinal tract results from a localized form of NEC or from a distinct lesion of unknown etiology has not yet been ascertained. Some ideas concerning the etiology of this entity, as well as some diagnostic aspects are discussed.

Localized pseudomembranous colitis simulating carcinoma of the cecum

A 76-yr-old woman complained of right lower quadrant abdominal pain, nausea, and fever. There was no history of antibiotic therapy or preceding diarrhea. At laparotomy, a cecal lesion simulating a tumor was found with an otherwise normal colon. Right hemicolectomy was performed. Pathological examination showed pseudomembranous colitis confined to the cecum. It is suggested that pseudomembranous colitis unrelated to prior exposure to antimicrobial agents can occur without diarrhea, and may be a localized process mimicking colonic carcinoma.

Serum copper level in gynecologic malignancies

Serum copper level was determined before operation in 179 patients with various histologically proved gynecologic tumors: malignant, benign, or metastases to the ovary. Serum copper level was significantly higher (p less than 0.01) in all groups of patients with cancer and in the benign group when compared with control subjects. Serum copper level correlated well with stage of cancer disease (r = 0.70 to 0.79) except for ovarian carcinoma, in which serum copper level was already significantly elevated in Stages I and II. The sensitivity of serum copper level greater than 150 micrograms/dl in detecting malignancy was 87% to 100% in late cancer stages in all malignancies. Our data imply that the addition of serum copper level determination to other screening tests could increase their sensitivity.