Two unusual cases of Anderson-Fabry disease in a Japanese family

A 16-year-old Japanese girl was admitted to our hospital on February 27, 2001, for acute renal failure. She had not shown proteinuria or hematuria in any school examination through 2000. The first renal biopsy specimen showed focal segmental glomerulosclerosis and tubulointerstitial change. Electron microscopy showed numerous myeloid bodies in the glomerular epithelium suggesting the diagnosis of Anderson-Fabry disease. After electron microscopy, we measured WBC alpha-galactosidase A, which was slightly decreased to 36.1 nmol/mg P/h (normal: 49.8 - 116.4). WBC alpha-galactosidase A levels for other family members were 74.3 for the mother, 4.8 for the father, 45.6 for the elder sister, and 16.3 for the younger sister. During the follow-up, she had two episodes of nephrotic syndrome, which responded well to steroid therapy. Both second and third renal biopsy showed numerous myeloid bodies by electron microscopy. A 52-year-old man, the father of the case one patient, was admitted for renal biopsy because of proteinuria and low levels of WBC alpha-galactosidase. Biopsy specimen showed typical changes under light microscopy and typical myeloid bodies by electron microscopy. Our cases underscore the importance of electron microscopy when examining the biopsy specimen and suggest that undiagnosed Anderson-Fabry disease may be present, in particular on chronic dialysis.

Hypotensive and sedative effects of clonidine injected into the rostral ventrolateral medulla of conscious rats

We examined the effects of clonidine injected unilaterally into the rostral ventrolateral medulla (RVLM) of conscious, unrestrained rats. We also examined whether the local alpha(2)-adrenoceptor mechanism contributed to the action of clonidine injected into the RVLM. Injection of clonidine but not vehicle solution significantly decreased the mean arterial pressure (MAP), heart rate (HR), and renal sympathetic nerve activity (RSNA) in conscious, unrestrained rats as well as in propofol-anesthetized rats. The frequency of natural behavior was significantly lower after clonidine injection than after vehicle injection. The depressor and sympathoinhibitory responses were significantly larger in the propofol-anesthetized rats than in the conscious rats. Coinjection of a selective alpha(2)-adrenoceptor antagonist, 2-methoxyidazoxan, with clonidine into the RVLM significantly attenuated the depressor, bradycardiac, sympathoinhibitory, and sedative effects of clonidine injected alone. In conclusion, clonidine injected into the RVLM decreased MAP, HR, and RSNA and caused sedation in conscious, unrestrained rats. The action of clonidine in the RVLM was at least partly mediated by alpha(2)-adrenoceptor mechanisms.

Cardiovascular and sympathetic effects of L-glutamate and glycine injected into the rostral ventrolateral medulla of conscious rats

The aim of the present study was to examine the effects of L-glutamate and glycine microinjected into the rostral ventrolateral medulla (RVLM) in conscious unrestrained rats. Microinjection of 2 nmol of L-glutamate increased the mean arterial pressure (MAP) and renal sympathetic nerve activity (RSNA) in the conscious rats. The RSNA responses were significantly larger in the conscious rats than in anesthetized rats, while the magnitude of the pressor responses was similar in conscious and urethane-anesthetized rats. L-Glutamate injection significantly decreased heart rate in the conscious rats, whereas it increased the heart rate slightly but not significantly in the anesthetized rats. Microinjection of 100 nmol of glycine into the RVLM of conscious rat decreased MAP and RSNA. In 2 of the 6 rats examined, the depressor and sympathoinhibitory responses were preceded by a few seconds of a pressor and sympathoexcitatory phase. The decreases of RSNA in response to glycine injection were significantly larger in the conscious rats than in the anesthetized rats, whereas the magnitude of the depressor responses was similar in the two groups of rats. Heart rate decreased in response to glycine injection into the RVLM in the conscious and the anesthetized rats. In conclusion, in conscious unrestrained rats, as well as in urethane-anesthetized rats, L-glutamate acts as a sympathoexcitatory agent and glycine acts as a sympathoinhibitory agent in the RVLM. The sympathetic responses to these amino acids are larger in conscious rats than in anesthetized rats.

Ouabain-like immunoreactivity in the medulla oblongata of rats

An isomer of ouabain, the ouabain-like compound (OI,C), may participate in the regulation of body fluid volume and vascular tone. Forebrain regions, especially the hypothalamus, are reported to be sites of OLC action in the central nervous system. The medulla oblongata is another critical area involved in central cardiovascular regulation. We reported that the microinjection of either monoclonal antibody to ouabain T8B11 or Fab fragment of digoxin-specific antibody into the rostral ventrolateral medulla significantly decreased mean arterial pressure and renal sympathetic nerve activity in anesthetized normotensive rats (TERUYA et al.: J. Clin. Invest. 99: 2791-2798, 1997). Using T8B11, we examined the ouabain-like immunoreactivity in the medulla oblongata of normotensive rats. In periodate-lysine-paraformaldehyde fixed tissues, ouabain-like immunoreactive neurons were detected in the nuclei and regions in the medulla oblongata including the ventrolateral medulla, ventromedial medulla, nucleus ambiguus, caudal raphe nuclei, nucleus of solitary tract, and dorsal motor nucleus of the vagus. When an Fab fragment of digoxin-specific antibody was used as a first antibody, the digoxin-like immunoreactive neurons were distributed in almost the same pattern as those observed with the use of T8B11. In the brain fixed with the "three-step" procedure developed by YAMADA et al. (1987), which was used in a previous ouabain immunohistochemical study of the hypothalamus, ouabain-like immunoreactivity in the medulla oblongata was much weaker in intensity and less restricted in distribution than that in the hypothalamus. These findings suggest that ouabain-like immunoreactivities are present in the medulla oblongata with a manner of distribution different from that seen in the hypothalamus. Some ouabain-immunopositive nuclei and regions in the medulla oblongata, especially the rostral ventrolateral medulla, may be other OLC action sites.

Prolonged NOS inhibition in the brain elevates blood pressure in normotensive rats

Systemic inhibition of nitric oxide synthase (NOS) evokes hypertension, which is enhanced by salt loading, partly via augmented sympathetic activity. We investigated whether inhibition of brain NOS elevates blood pressure (BP) in normotensive rats and, if so, whether the BP elevation is enhanced by salt loading. After a 2-wk low-salt (0.3%) diet, male Sprague-Dawley (SD) rats were divided into four groups. Groups 1 and 2 received a chronic intracerebroventricular infusion of 0.5 mg . kg-1 . day-1 of NG-monomethyl-L-arginine (L-NMMA), and groups 3 and 4 were given artificial cerebrospinal fluid (aCSF). Groups 1 and 3 were placed on a high-salt (8%) diet, whereas groups 2 and 4 were on a low-salt diet. On day 9 or 10, group 1 showed significantly higher mean arterial pressure (MAP) in a conscious unrestrained state (129 +/- 3 mmHg vs. 114 +/- 3, 113 +/- 1, and 108 +/- 3 mmHg in groups 2, 3, and 4, respectively, P < 0.05). On a high-salt diet, response of renal sympathetic nerve activity but not of BP to air-jet stress was significantly larger in rats given L-NMMA than in rats given aCSF (29 +/- 4% vs. 19 +/- 3%, P < 0.05). When the intracerebroventricular infusions were continued for 3 wk, MAP was significantly higher in rats given L-NMMA than in rats given aCSF irrespective of salt intake, although the difference was approximately 7 mmHg. Thus chronic inhibition of NOS in the brain only slightly elevates BP in SD rats. Salt loading causes a more rapid rise in BP. The mechanisms of the BP elevation and its acceleration by salt loading remain to be elucidated.

Contribution of alpha 2-adrenoceptors in caudal ventrolateral medulla to cardiovascular regulation in rat

The inhibitory action of alpha 2-agonists on the cardiovascular neurons has been elucidated in the rostral ventrolateral medulla (RVLM) but not in the caudal ventrolateral medulla (CVLM). Our study aimed to clarify whether microinjection of clonidine into the CVLM elicits any cardiovascular effect and whether endogenous alpha 2-adrenoceptor-mediated mechanisms contribute to the tonic activity of the CVLM neurons. In male Sprague-Dawley rats (7-9 wk old, 270-320 g) anesthetized with urethan, unilateral microinjection of 8 nmol of clonidine into the CVLM (n = 10) increased mean arterial pressure (MAP) and renal sympathetic nerve activity (RSNA) by 12.1 +/- 1.8 mmHg (mean +/- SE, P < 0.01) and 25.8 +/- 4.8% (P < 0.01), while heart rate (HR) remained unaltered. Unilateral microinjection of 2 nmol of SKF-86466, a selective blocker of the alpha 2-adrenoceptors, into the CVLM (n = 10) decreased MAP, HR, and RSNA (-11.6 +/- 2.6 mmHg, -26 +/- 7 beats/min, and -15.3 +/- 1.7%, respectively, P < 0.01 for each). Artificial cerebrospinal fluid caused neither a cardiovascular effect nor a sympathetic response. Prior injection of SKF-86466 into the ipsilateral CVLM attenuated the effects of clonidine. Bilateral microinjection of muscimol into the RVLM abolished the effects of both clonidine and SKF-86466 injected into the CVLM. The pressor and sympathoexcitatory effects of clonidine injected into the CVLM suggest a neuroinhibitory action of the drug on the CVLM neurons. In addition, the depressor and sympathoinhibitory effects of SKF-86466 injected into the CVLM indicated that activation of alpha 2-adrenoceptors by endogenous ligand inhibits CVLM neurons. The effects of clonidine and the alpha 2-adrenoceptor antagonist in the CVLM require the integrity of the RVLM.

Kinetic analysis of the growth rate of the flagellar hook in Salmonella typhimurium by the population balance method

The growth rate of flagellar hooks in Salmonella typhimurium was analyzed by computer-aided simulation of the length distributions of mutant hooks of uncontrolled length (polyhooks). The wild-type hook has a relatively well-controlled length, with an average of 55 nm and a standard deviation of 6 nm. Mutations in the fliK gene give rise to polyhooks. A histogram of the lengths of polyhooks from a fliK mutant shows a peak at 55 nm with a long monotonic tail extending out to 1 microm. To analyze the growth rate, we employed the population balance method. Regression analysis showed that the histogram could fit a combination of two theoretical curves. In the first phase of growth, the hook starts with a very fast growth rate (40 nm/min), and then the rate exponentially slows until the length reaches 55 nm. In the second phase of growth, where the hook length is over 55 nm, the hook grows at a constant rate of 8 nm/min. Second mutations in either the fliK or flhB genes, as found in pseudorevertants from fliK mutants, give rise to polyhook filaments (phf). The ratio between the numbers of hooks with and without filament was 6:4. The calculated probability of filament attachment to polyhooks was low so that the proportion of hooks that start filament growth was only 2% per minute. The lengths of polyhooks with and without filaments were measured. A histogram of hook length in phf's was the same as that for polyhooks in single-site fliK mutants, against the expectation that the distribution would shift to a shorter average. The role of FliK in hook length control is discussed.

Congenital true diverticula of the esophagus: a case report

Pseudodiverticulosis secondary to gastroesophageal reflux is a common disease in adults, but true esophageal diverticula are rare in infants and children. A 5-year-old boy was well until the age of 1 1/2 years when he started vomiting. An upper gastrointestinal series showed two diverticula bulging from the posterior right side of the middle esophagus associated with slight hiatal hernia and short esophagus. Diverticulectomy, the Collis-Nissen antireflux procedure, and pyloroplasty were performed simultaneously through a left thoracoabdominal incision. Histological examination of the diverticula showed that the wall of each diverticulum consisted of a full-thickness of esophageal wall. Because there was no tracheal remnant in the diverticula, this lesion is more likely to be a true diverticulum than a duplication.

[Endogenous digitalis-like factor]

Evidence suggests the existence of a Na,K-ATPase inhibitor, so called endogenous digitalis-like factor (EDLF), in plasma. This substance has been postulated to enhance renal tubular sodium excretion and to increase peripheral vascular resistance. Recently, plant ouabain or its isomer (ouabain-like compound, OLC) was purified from human plasma and bovine hypothalamic extract. The OLC is considered to be a candidate for the EDLF. The OLC has been implicated in the pathogenesis of sodium-dependent hypertension. Furthermore, accumulating evidence suggests central nervous system as a site of hypertensinogenic action of OLC.

Role of ouabain-like compound in the rostral ventrolateral medulla in rats

To determine whether ouabain-like compound (OLC) exerts modulatory influences on the activity of vasomotor neurons in the rostral ventrolateral medulla (RVLM), we examined the effects of microinjecting ouabain, digoxin-specific antibody Fab fragments, and mAb against ouabain on the rat RVLM. Microinjection of ouabain into the unilateral RVLM of anesthetized normotensive rats elicited dose-dependent increases in mean arterial pressure (MAP) and renal sympathetic nerve activity (RSNA). The pressor and sympathoexcitatory effects of ouabain in the RVLM were reversed by microinjections of an M2 muscarinic antagonist, gallamine, or digoxin-specific antibody Fab fragments. Furthermore, a prior microinjection in the RVLM of gallamine, digoxinspecific antibody Fab fragments, or kainic acid or intravenous injection of hexamethonium all prevented the pressor and sympathoexcitatory effects induced by a subsequent microinjection of ouabain. Microinjections of either digoxinspecific antibody Fab fragments or gallamine per se significantly decreased baseline MAP and RSNA. Injection of digoxin-specific antibody Fab fragments attenuated the effects of a subsequent injection of gallamine. Microinjection of mAb against ouabain, but not nonspecific IgG, also significantly decreased baseline MAP and RSNA. These results suggest that OLC in the RVLM contributes to the tonic activity of vasomotor neurons in anesthetized normotensive rats, and the action of OLC in the RVLM is at least partly mediated by M2 muscarinic mechanisms.

Successful endoscopic balloon dilatation for hypertrophic pyloric stenosis

The authors successfully applied endoscopic balloon dilatation for the treatment of hypertrophic pyloric stenosis (HPS). The patient was an infant girl who had undergone repair of a giant omphalocele. Endoscopic balloon dilatation was performed using a 9-mm endoscope and an 8-mm polyethylene terephthalate (PET) balloon dilator. Dilatation was performed three times for 10 minutes. Vomiting continued after the dilatation. At the second session, dilatation was performed using a 12-mm PET balloon dilator. The 9-mm endoscope then passed through the pylorus. The patient has had no episodes of vomiting since the second treatment. This procedure is an important therapeutic option for selected patients with HPS.

Bipolar electrode implantation for myoelectrical recordings of rat bowel

This report describes a technique to implant bipolar electrodes into the rat bowel. We implanted a total of 129 pairs of bipolar electrodes into the bowel of rats. 124 pairs of electrodes (96.3%) have continuously functioned allowing repeated myoelectrical readings. Of these, 69 electrodes functioned over 8 weeks. Only 5 electrodes (3.7%) failed. The advantage of our technique includes: (1) high success rate in implantation, (2) long term durability, and (3) less technical difficulty.

[Currarino triad : a case report]

The authors report a case of Currarino triad comprising anorectal malformations, sacral bony anomaly and presacral mass. A 1-year-old boy was presented with constipation as his chief complaint. No neurological deficit was found on admission. There was no cutaneous evidence of underlying spinal dysraphism. Lumbar X-ray films showed bony defect caudal to the third sacral vertebra. A barium-enema examination revealed an anterior displacement of the rectum. A myelography showed a presacral cavity filled with contrast medium. MRI demonstrated a thick filum terminale, and a round hypointense mass in the pelvis on T1 weighted images and hyperintense on T2 weighted images. Surgically we released the thick filum terminale, and obliterated the anterior sacral meningocele, because total removal would have been hazardous. Postoperatively transient dysuria was observed for a month, and the difficulty in defecation persisted. Recognition of this rare condition will lead to correct diagnosis and proper treatment.

Motility of isolated bowel segment Iowa model III

The isolated bowel segment (IBS) is an amesenteric segment of bowel that is devoid of extrinsic nerves and yet is viable with motility and absorption preserved after its mesentery is completely severed. The IBS is created by initial coaptation of a loop of bowel to a host organ, such as muscle (Iowa model I), liver (Iowa model II), or intestine, and secondary severance of its mesentery several weeks later. In previous studies using Iowa models I and II, the viability, motility, and absorption of the IBS were preserved by vascular collaterals, which form across the coaptation. In rats, an IBS was created in the jejunum by initial enteroenteropexy (Iowa model III), followed by its mesenteric division five weeks later. At the second laparotomy, bipolar electrodes were implanted in the IBS and the adjacent jejunum. One week later, myoelectrical recording was performed during a fasting state. Coordinated abroad propagation of migrating motor complex (MMC) was observed in the IBS. The MMC period was 16.9 +/- 1.7 and 19.3 +/- 0.8 min in the intact bowel, and 22.8 +/- 0.8 min in the IBS (P = 0.1). After feeding, the MMC in the IBS was replaced by irregular spike burst activity similar to that observed in the intact bowel. This study concludes that the IBS Iowa model III can be used for studies of bowel physiology.

A rare case of achalasia coexistent with sigmoid megacolon and associated with epilepsy

A case of achalasia coexistent with sigmoid megacolon in a 38-year-old man with known epilepsy is described. The patient was referred to the Ryukyu University Hospital with a 4-year history of dysphagia and heartburn and a 1-year history of abnormal bowel movement. On admission, upper gastrointestinal (GI) series demonstrated a dilated, tortuous thoracic esophagus with a flask-type configuration. Barium enema studies showed a dilated sigmoid colon from the rectosigmoid junction to the descending colon. Myotomy (modified Jekler-Lhotka's procedure) for achalasia and simple sigmoidectomy for sigmoid megacolon were carried out. The biopsied wall of the narrowed esophageal segment at operation showed decreased numbers of ganglion cells in Auerbach's plexus and atrophy of the muscle fibers. The resected dilated sigmoid colon revealed degeneration and markedly decreased numbers of ganglion cells in Auerbach's and Meissner's plexuses. The patient's postoperative course was uneventful and he has been doing well since surgery. The present case is very interesting and to our knowledge, such a case is rare in the literature. We believe that the abnormalities of the ganglion cells may be due to the same etiologic factor as the sigmoid megacolon. The association of the two pathologic processes is discussed, together with a brief review of the literature.

Absorption in the isolated bowel segment

An isolated bowel segment (IBS) is a viable mesenteric segment of intestine. This study was undertaken to investigate the effects of mesenteric vascular and neural supply on intestinal absorption. Ten rats were used for leucine absorption and another 10 for glucose absorption experiments. L-leucine, 12 ml of 15.0 mM/L, or 3.0 mM/L of D-glucose solution were recirculated through the IBS (n = 5) and rat jejunum that underwent sham operation (n = 5) at 2.56 ml/min for 90 min. Absorption was expressed as millimoles of leucine or glucose per gram of mucosal protein. The Student's t test was used for statistical analysis; a p < or = 0.05 was considered significant. The net absorption of L-leucine was 36.20 +/- 3.31 mM/g of mucosal protein in the IBS and 15.52 +/- 1.48 mM/g of mucosal protein in the control group (p < 0.001). The net absorption of D-glucose was 3.82 +/- 0.26 mM/g of mucosal protein in the experimental group and 4.34 +/- 0.31 mM/g of mucosal protein in the control group (p = 0.02). This study concludes that absorption of leucine and glucose in the IBS is preserved after mesenteric division.

Mucosal morphology in isolated bowel segments: importance of exposure to luminal contents

An isolated bowel segment (IBS) is a loop of intestine that has been freed from its mesenteric attachment after the development of vascular collaterals between the antimesenteric surface of the gut and the host organ. Surgical creation of such artificially vascularized isolated bowel segments is of interest to researchers for a variety of studies, and may be useful in the treatment of short bowel syndrome, allowing longitudinal division of the remaining small bowel to double its length. We created four surgical variants to study the ability of the collateral blood supply to maintain mucosal integrity in the presence or absence of normal luminal contents. In all groups, a collateral blood supply was created in a 5- to 7-cm segment of adult rat jejunum by hepatoenteropexy (Iowa model II). In Thiry-Vella (T-V) and isolated bowel segment (IBS) rats, this segment was exteriorized at both ends to exclude luminal contents. Control and IBS in continuity (IBS-C) loops were left in continuity. The mesentery of IBS and IBS-C rats was divided 5 weeks later, leaving the experimental segment entirely dependent on the collateral circulation. All animals were harvested at 7 weeks after the initial surgery. Tissues were analyzed for mucosal weight, protein content per centimeter of bowel, length of villi, depth of crypts, DNA content, and sucrase activity. We found that segments retaining luminal continuity had significantly higher mucosal weight and DNA content per centimeter of bowel compared with exteriorized loops.

The isolated bowel segment (Iowa model II): motility across the anastomosis with or without mesenteric division

In previous reports, anastomosis has been shown to disrupt the myoelectric activity of the bowel. However, these studies have failed to delineate the role of the extrinsic nerves. Using an isolated bowel segment (IBS) and an amesenteric bowel segment (ABS), motility was evaluated by myoelectric recording across a bowel anastomosis. Ten rats were divided equally into the experimental group with the IBS and the control group with the ABS. In the IBS group, an 8-cm segment of jejunum was divided, reanastomosed, and coapted to the liver margin (Iowa model II). In the ABS group, an 8-cm segment of jejunum was coapted to the liver margin without disruption of bowel continuity (Iowa model II variant). Two weeks later, bipolar electrodes were implanted in the IBS and ABS, and normal jejunum in both groups. Mesenteric division (MD) was performed 4 weeks later to eliminate extrinsic innervation. Myoelectrical recordings were taken 2 weeks before and after MD. In the control group with IBS, incoordination in the propagation of the migrating motor complex (MMC) and reduction in the frequency of slow waves (FSW) were observed across the anastomosis and were unchanged by MD. In the control group with the ABS, the MMC and FSW were identical to that in the normal jejunum and were unaffected by MD. In both groups postprandial inhibition of the MMC was the same as in the normal jejunum and was unaffected by MD. This study confirms that incoordination in propagation of the MMC and reduction in FSW occur across a bowel anastomosis, and elimination of extrinsic innervation does not affect the autonomy of these changes.(ABSTRACT TRUNCATED AT 250 WORDS)

The isolated bowel segment (Iowa Model II): absorption studies for glucose and leucine

A model of the isolated bowel segment (IBS, Iowa Model II) was successfully created in experimental animals using a new surgical technique we developed. The IBS is completely free of its mesenteric attachment, yet its viability is preserved. The technique consists of two staged procedures: (1) initial enteropexy between the anterior margin of the liver and the antimesenteric border of the IBS with its ends forming cutaneous stomas; and (2) division of the IBS mesentery 5 weeks later. The IBS is nourished by vascular collaterals that form at the hepatoenteropexy during the interval between these two procedures. Our previous studies demonstrated preserved viability and motility in the IBS. This study was undertaken to test absorption in the IBS. In 25 rats (experimental group), the IBS (Iowa Model II) was created using an 8-cm-long isolated segment of jejunum. In 15 rats (control group), an 8-cm-long segment of jejunum was arranged to form a Thiry-Vella loop. Five weeks later, the IBS mesentery was divided in the experimental group, and sham laparotomy was performed in the control group animals. Absorption of glucose and leucine was studied in 13 rats of the experimental group and 6 of the control group using a constant single perfusion technique at 3, 8, and 11 weeks after the initial operation. The results were compared between the two groups. There was a 25% to 35% reduction in absorption of glucose and leucine in both groups with the advance of time, but no significant difference was observed between the groups except in leucine absorption at 11 weeks after the initial operation. This study concludes that absorption of glucose and leucine is preserved in the IBS after its mesentery is divided, suggesting that the IBS can be used as a functioning bowel for bowel reconstruction.

The isolated bowel segment (Iowa model II) created in functioning bowel

In experimental rats (n = 15), an isolated bowel segment (IBS) was created by (1) initial enteropexy between an 8-cm-long jejunal segment and the liver margin (hepatoenteropexy; Iowa model II) with its proximal and distal ends divided and immediately reanastomosed in an end-to-end fashion to reconstruct the bowel; and (2) secondary division of the IBS mesentery 5 weeks later. The IBS is then completely free of its mesentric and intramural nervous and vascular communications. The viability of the IBS is preserved by vascular collaterals developed at the hepatoenteropexy. Twelve rats proceeded to the second procedure, having tolerated regular rat chow with satisfactory weight gain. The Iowa model II created in functioning bowel was evaluated by contrast studies and myoelectrical activities. Contrast studies demonstrated peristalsis in the IBS. In the myoelectrical recordings, the frequency of slow wave was 32.5 +/- 1.0 in the IBS and 36.3 +/- 0.8 in the normal bowel (P less than .05). During fasting, the migrating motor complex (MMC) was observed to propagate aborally in the IBS in a coordinated fashion. The cyclic period of the MMC was 17.2 +/- 1.1 minutes in the IBS and 15.8 +/- 0.8 minutes in the normal bowel (P = .30). We conclude from this study that (1) the IBS (Iowa model II) retains motor function as demonstrated by successful feeding, as well as contrast studies and myoelectrical recordings that were essentially identical to those in the normal bowel; and (2) the IBS (Iowa model II) has significant research potential for studies of bowel physiology.

Immunohistochemical and electron microscopic findings in a case of mixed hamartoma of the liver

A case of mixed hamartoma of the liver in a 36 day old female infant is reported herein. The resected tumor was well demarcated, measured 7.5 X 7.0 cm and weighed 179 gm. Microscopically, the tumor was composed of loose fibrous stroma intermingled with spindle and polygonal cells and ductular structures. The spindle and polygonal tumor cells displayed the distinct cytoplasmic staining for alpha-1-antitrypsin. Most of the tumor cells showed the characteristic ultrastructural features of immature hepatocytes, having numerous cytoplasmic microvillous structures, abundant rough and smooth endoplasmic reticulum and mitochondria. These findings suggest that embryonic liver cells, which are capable of transforming into biliary structures and hepatocytes, serve as essential elements of mixed hamartoma of the liver.