Mapping of two tumor suppressor genes in the pig

Mutations in the breast cancer 1, early onset (BRCA1) gene confer an increased risk of breast and ovarian cancer in humans. The human MAD (mothers against decapentaplegic, Drosophila) homolog 4 (MADH4) locus is a target for deletion in pancreatic and other cancers. Given the role of the pig in biomedical studies, pig orthologs of BRCA1 and MADH4 were identified and localized in the porcine genome.

Long-term survival among patients operated upon for peptic ulcer disease

BACKGROUND

Although surgery has been used widely for treating peptic ulcer disease, there is conflicting evidence with respect to subsequent life expectancy and the determinants of mortality. Our aim was to compare long-term survival in a large, population-based cohort of operated patients with that expected in the general population.

METHODS

We followed 471 Rochester, Minnesota residents who had surgery for peptic ulcer at the Mayo Clinic during 1956-85 for a total of 6174 person-years. Patients were followed through their complete (inpatient and outpatient) medical records in the community until death or last clinical contact and death certificates were obtained for all who succumbed. We compared observed survival and cause-specific death rates in this cohort with expected values and identified the determinants of short (30 day) and long-term mortality.

RESULTS AND CONCLUSIONS

Survival was worse than expected, but excess deaths were confined to those with perforated ulcers (42 deaths observed; 18.8 expected). Independent predictors of death included age, male gender, emergency operation, gastric ulcer and cigarette smoking. Most deaths were due to heart disease and cancer, but only those due to digestive diseases (standardized mortality ratio (SMR) 3.8, 95% CI 2.4-5.7) and respiratory diseases (SMR 1.9, 95% CI 1.3-2.7) were increased compared to expected figures. Overall survival was reduced in this cohort but was normal among those whose ulcers were not perforated. However, the data suggest an adverse role for alcohol and smoking in these patients.

Surgical treatment of Roux stasis syndrome

We wondered whether the slow gastric emptying of the Roux stasis syndrome could be improved by performing a corrective "uncut" Roux operation. Five dogs had a standard Roux gastrectomy and placement of serosal electrodes on the proximal jejunum and Roux limb. After recovery, baseline myoelectrical and gastric emptying data were collected. The animals then underwent a second operation: take down of the Roux limb, restoration of jejunal continuity, and construction of an "uncut" Roux limb. After the animals recovered, the tests were repeated. The slow frequency of pacesetter potentials (PPs) in the standard Roux limb (mean +/- standard error of the mean 14 +/- 0.4 cpm) was unchanged after the uncut Roux operation (14 +/- 0.5 cpm, P > 0.05). However, a greater percentage of PPs propagated aborally in the uncut Roux limb (81% +/- 4%) than in the standard Roux limb (53% +/- 7%, P <0.05). Nonetheless, gastric emptying of a 250 ml 10% dextrose liquid meal was not speeded by the uncut Roux operation (uncut Roux = 36% +/- 5% emptied by 20 minutes vs. standard Roux = 35% +/- 7%; P >0.05). Bile acid concentrations in gastric aspirates were minimal after both operations (0.7 +/- 0.2 micromol/L vs. 0.6 +/- 0.1 micromol/L; P >0.05). The conclusion was that more PPs propagated in the aborad direction in the uncut Roux limb than in the standard Roux limb, but gastric emptying was not speeded by the uncut Roux operation. Both operations were equally effective in preventing bile reflux into the gastric remnant.

Restoration of myoelectrical propagation across a jejunal transection using microsurgical anastomosis

The aim of this study was to determine whether microsurgical anastomosis can restore propagation of jejunal pacesetter potentials (PPs) across a site of canine jejunal transection and preserve motility and transit in bowel distal to the transection. A complete jejunal transection with exact microsurgical anastomosis was performed in five dogs, while five dogs with intact jejunum and five dogs with complete transection and end-to-end conventional macrosurgical anastomosis were used as controls. Long-term recording electrodes and intraluminal, open-tipped pressure catheters were implanted in all dogs. The mean frequency of PPs decreased distal to the transection in both groups of transected dogs. However, aborad propagation of PPs across the anastomosis occurred episodically by 3 months in each dog that had a microsurgical anastomosis, but never occurred in any dog with a conventional macroanastomosis. Moreover, the motility and transit in bowel distal to the transection were unaltered in the dogs with a microsurgical anastomosis, whereas they decreased in the dogs with a macroanastomosis. The conclusion was that microsurgical anastomosis of transected canine jejunum restored episodic propagation of PPs across the anastomosis, and preserved motility and maintained transit in bowel distal to the anastomosis. The conventional macroanastomosis did none of these.

Human follicular dendritic cells inhibit superantigen-induced T-cell proliferation by distinct mechanisms

Follicular dendritic cells (FDCs) reside within germinal centers of secondary lymphoid tissue where they play a critical role in antigen-driven immune responses. FDCs express numerous adhesion molecules that facilitate cellular interactions with B and T cells within the germinal center microenvironment. Although human FDCs have been shown to influence B-cell development, very little is known about the ability of FDCs to regulate T-cell responses. To investigate this functional aspect of FDCs, highly enriched preparations were isolated by magnetic cell separation using the FDC-restricted monoclonal antibody HJ2. We found that isolated human FDCs inhibited proliferation of both autologous and allogeneic T cells, and were dependent on the number of FDCs present. Inhibition by FDCs was observed using two serologically distinct superantigens at multiple concentrations (Staphylococcus enterotoxin A and B). In contrast, B cells failed to inhibit, and often augmented superantigen-induced T-cell proliferation. Antibody-blocking studies showed that CD54 and CD106 were involved in the ability of FDC to inhibit T-cell proliferative responses. When FDCs and T cells were separated by a semipermeable membrane, the inhibitory effect was partially abrogated, demonstrating that in addition to cell-cell interactions, a soluble factor(s) was also involved in the process. The addition of indomethicin to cultures improved the proliferative response in the presence of FDCs, indicating that inhibition was mediated, in part, by prostaglandins. These results indicate that FDCs regulate T-cell proliferation by two molecular mechanisms and that FDC:T-cell interactions may play a pivotal role in germinal center development.

[The physiology of intestinal pouches]

To summarize, J-shaped and W-shaped ileal pouches serve as adequate neorectal reservoirs after proctocolectomy. These pouches anastomosed directly to the anal canal are as distensible and capacious and as readily evacuated as the rectum in health. However, the use of S- or H-shaped ileal pouches, which have efferent limbs positioned between the pouch and the anal canal, sometimes leads to outflow obstruction and incomplete evacuation. There is little doubt that neorectums made of ileum can allow patients to have entirely "normal" patterns of fecal continence. Nonetheless, with pouch distension, large-amplitude, propulsive pouch contractions occur. These large pressure waves bring on the urge to defecate. They stress the anal sphincters more acutely than either the infrequent, small-amplitude, nonpropulsive contractions or clustered contractions of the healthy rectum. Nonetheless, patients learn to recognize the different signals heralding the impending need for evacuation from the ileal pouch and deal with them. Jejunal pouches, because of their greater distensibility and larger capacity, and the greater frequency of interdigestive migrating myoelectric complexes (MMCs) occurring in them, hold the promise of being a better rectal substitute than ileal pouches. They are more difficult to construct, however. Colonic pouches, when anastomosed to the anal canal after rectal resection, also act as adequate fecal reservoirs. Their main drawback is the inability of some patients to empty them. Small (5 cm) colonic pouches seem to empty better than larger (10-15 cm) ones. Jejunal pouches and colonic segments used as gastric substitutes after gastrectomy provide a better reservoir for ingested food than straight jejunal segments. The main drawback of the pouches is their inability to triturate the solid content of a meal and to regulate the rate of its emptying into the small intestine. Liquids and solids likely empty from these pouches at the same rate, in contrast to the slower emptying rate of solids from the healthy stomach. This likely leads to maldigestion of solids, perhaps contributing to the weight loss often found after gastrectomy.

New insights into porcine-human synteny conservation

Eleven genes were mapped to the porcine genome with the aim of improving the human-porcine comparative gene map. Five of these genes were from regions of the human genome painted by porcine chromosomal probes; of these, two mapped to chromosomes not expected from the painting results. Among the six genes from human regions not painted by porcine chromosomal probes, three genes did not map where expected by the principle of parsimony. Several of the gene assignments indicate the existence of small regions of conserved synteny not detected by heterologous chromosome painting, especially in telomeric regions. We have also detected new rearrangements in gene order within the regions of correspondence between human Chromosome (HSA) 15 and porcine Chromosome (SSC) 1 as well as between HSA4 and SSC8.

Use of a colonic pouch as a rectal substitute after rectal excision

Mid or distal rectal resection with straight coloanal anastomosis effectively treats distal rectal cancer and avoids a permanent stoma. However, the straight colonic segment is a poor reservoir for stools, and patients usually experience varying degrees of impaired rectal function after operation, including frequent bowel movements, incontinence, tenesmus, and soiling. In contrast, a J-shaped colonic pouch provides an adequate neorectal reservoir after operation. Patients with a colonic pouch-anal canal anastomosis have fewer bowel movements per day than patients with straight colorectal or coloanal anastomosis. Furthermore, the morbidity of the colonic pouch is not greater than that of the straight coloanal anastomosis. An important technical aspect of the colonic pouch procedure is that the limbs used to form the pouch must be no longer than 5 to 6 cm. Patients with larger pouches experience emptying difficulties. Also, the level of the anastomosis between the pouch and the anal canal must be no more than 4 cm from the anal verge, again to avoid problems with defecation. With these caveats, the operation should be considered in patients who require excision of the mid and distal rectum for cancer.

Near-total completion gastrectomy for severe postvagotomy gastric stasis: analysis of early and long-term results in 62 patients

The aim of this study was to evaluate results of completion gastrectomy for severe postgastrectomy gastric stasis. A total of 51 women and 11 men underwent completion gastrectomy for gastric stasis between 1985 and 1996; follow-up was complete in 98% at 5.4 +/- 5 years. All patients had modified Visick scores preoperatively of grade III (37%) or IV (63%). Presentation included combinations of nausea, vomiting, postprandial pain, chronic abdominal pain, and chronic narcotic use. All had undergone prior vagotomy and had a median of four previous gastric operations. Hospital mortality was zero. Complications occurred in 25 patients (40%) and included the following: narcotic withdrawal syndrome (18%), ileus (10%), wound infection (5%), intestinal obstruction (2%), and anastomotic leak (5%). All or most symptoms were relieved in 43% (Visick grade I or II), but 57% of the patients remained in Visick grade III or IV. Nausea, vomiting, and postprandial pain were reduced from 93% to 50%, 79% to 30%, and 58% to 30%, respectively (P<0.05), but chronic pain, diarrhea, and dumping syndrome were not significantly affected. Univariate analysis revealed no preoperative characteristic to be predictive of good outcome. Logistic regression analysis suggested that the combination of nausea, need for total parenteral nutrition, and retained food in the stomach predicted a poor outcome (P<0.05). Completion gastrectomy is successful in 43% of patients. The combination of nausea, need for total parenteral nutrition, and retained food at endoscopy are negative prognostic factors.

Oxidative stress in toxicology: established mammalian and emerging piscine model systems

Interest in the toxicological aspects of oxidative stress has grown in recent years, and research has become increasingly focused on the mechanistic aspects of oxidative damage and cellular responses in biological systems. Toxic consequences of oxidative stress at the subcellular level include lipid peroxidation and oxidative damage to DNA and proteins. These effects are often used as end points in the study of oxidative stress. Typically, mammalian species have been used as models to study oxidative stress and to elucidate the mechanisms underlying cellular damage and response, largely because of the interest in human health issues surrounding oxidative stress. However, it is becoming apparent that oxidative stress also affects aquatic organisms exposed to environmental pollutants. Research in fish has demonstrated that mammalian and piscine systems exhibit similar toxicological and adaptive responses to oxidative stress. This suggests that piscine models, in addition to traditional mammalian models, may be useful for further understanding the mechanisms underlying the oxidative stress response.

J ileal pouch-anal anastomosis for chronic ulcerative colitis: complications and long-term outcome in 1310 patients

AIM

The purpose of the study was to determine the risk of postoperative complications and the functional outcome after a hand-sewn ileal pouch-anal anastomosis (IPAA) for ulcerative colitis using a single J-shaped pouch design.

METHODS

Preoperative function, operative morbidity and long-term functional outcome were assessed prospectively in 1310 patients who underwent IPAA between 1981 and 1994 for ulcerative colitis.

RESULTS

Three patients died after operation. Postoperative pelvic sepsis rates decreased from 7 per cent in 1981-1985 to 3 per cent in 1991-1994 (P = 0.02). After mean follow-up of 6.5 (range 2-15) years, the mean number of stools was 5 per day and 1 per night. Frequent daytime and nighttime incontinence occurred in 7 and 12 per cent of patients respectively, and did not change over a 10-year period. The cumulative probability of suffering at least one episode of 'clinical' pouchitis was 18 and 48 per cent at 1 and 10 years and the cumulative probability of pouch failure at 1 and 10 years was 2 and 9 per cent respectively.

CONCLUSION

These results indicate that increased experience decreases the risk of pouch-related complications and that with time the functional results remain stable, but the failure rate increases.

1,25-Dihydroxy vitamin D3 inhibits adipocyte differentiation and gene expression in murine bone marrow stromal cell clones and primary cultures

Bone marrow stromal stem cells differentiate into adipocytes and osteoblasts. These two lineages are thought to be reciprocally related, in part due to the observation that the osteoblast-inducing factor, 1,25 dihydroxy vitamin D3 [1,25(OH)2D3], inhibited adipogenesis of rat femoral-derived stromal cell cultures. However, the literature is divided concerning the adipogenic effects of this steroid hormone. This work examined the effect of 1,25(OH)2D3 (10(-12)-10(-8) M) on murine femoral-derived bone marrow stromal cell differentiation in response to adipogenic agonists employing two different classes of nuclear hormone receptors: the glucocorticoid receptor (hydrocortisone) or peroxisome proliferator-activated receptors (thiazolidinediones). Experiments used the multipotent murine bone marrow stromal cell line, BMS2, and its subclones, as well as primary-derived murine bone marrow stromal cell cultures. In all systems examined, 1,25(OH)2D3 blocked adipogenesis induced by hydrocortisone, methylisobutylxanthine, and indomethacin based on flow cytometric analysis of lipid accumulation. This correlated with reduced messenger RNA levels of the late adipocyte gene markers, aP2 and adipsin. In the BMS2 subclone no. 24, the 1,25(OH)2D3 actions were concentration dependent. Whereas 1,25(OH)2D3 partially inhibited thiazolidinedione-induced adipogenesis in the parental BMS2 cell line, it had minimal effect on the thiazolidinedione-induced differentiation of the BMS2 subclone and primary cultures. These findings indicate that 1,25(OH)2D3, at nanomolar concentrations, completely inhibits murine bone marrow stromal cell differentiation in response to glucocorticoid-based adipogenic agonists but is a less effective adipogenic antagonist following induction with thiazolidinediones. This work supports the conclusion that 1,25(OH)2D3 inhibits murine femoral-derived bone marrow stromal cell adipogenesis.

Proctocolectomy with jejunal pouch-distal rectal anastomosis: an alternative to ileal pouch reconstruction

The aim of this study was to determine whether a jejunal pouch would have a lower resting pressure, be more distensible, and have more interdigestive migrating myoelectric complexes and less fecal bacterial overgrowth than would an ileal pouch after proctocolectomy and pouch-distal rectal anastomosis. In six conscious dogs with a jejunal pouch-distal rectal anastomosis and six with an ileal pouch-distal rectal anastomosis (controls), pouch distensibility and motility were measured using a barostat and perfused pressure-sensitive catheters passed per anum, pouch electrical activity was recorded using chronically implanted electrodes, and the number of bacteria per gram of stool was assessed by culture. Dogs with a jejunal pouch had lower resting pouch pressures, more distensible pouches, faster frequencies of pacesetter potentials in the pouch, more phase 3 intervals of the interdigesive migrating myoelectric complex reaching the pouch, but similar numbers and types of bacteria in their stools compared to the dogs with an ileal pouch. We concluded that jejunal pouches have a lower resting pressure, are more distensible, have more cleansing contractions, but a similar fecal flora compared to ileal pouches. A jejunal pouch has features that make it an attractive alternative to an ileal pouch for pouch-distal rectal or pouch-anal canal anastomosis after proctocolectomy.

Murine bone marrow stromally derived BMS2 adipocytes support differentiation and function of osteoclast-like cells in vitro

Stromal cells are required for in vitro osteoclast differentiation and maturation. The murine bone marrow stromally derived BMS2 cell line exhibits adipocytic and osteoblastic features as well as the ability to support lymphopoiesis and myelopoiesis. This work examined the ability of the BMS2 cell in either the preadipocyte or adipocyte state to support the formation of osteoclast-like cells. BMS2 cells can be induced to undergo adipogenic differentiation in response to treatment with glucocorticoids or thiazolidinedione compounds. Primary bone marrow cells, enriched for hematopoietic progenitors and depleted of their adherent stromal and macrophage populations, were stimulated with vitamin D3 (vitamin D; 10(-8) M) to undergo osteoclast differentiation and maturation when cocultured with BMS2 cells. In both preadipocyte and adipocyte-enriched BMS2 stromal layers, comparable numbers of tartrate-resistant acid phosphatase-positive osteoclast-like cells, characterized by their response to salmon calcitonin with an increase in cAMP and formation of resorption pits on bovine bone slices, were formed. The gene expression and protein levels of macrophage colony-stimulating factor produced by preadipocyte and adipocyte-rich BMS2 layers were comparable. However, adipocyte-rich stromal layers supported osteoclast-like cell formation longer in culture than preadipocytes, independent of the agent used to induce adipocyte differentiation. These studies demonstrate for the first time that fully differentiated adipocyte stromal cells can support osteoclast-like cell formation and function in vitro.

Internalization of Chlamydia by dendritic cells and stimulation of Chlamydia-specific T cells

Chlamydia species are the causative agents of trachoma, various forms of pneumonia, and the most common sexually transmitted diseases. Although the infection cycle has been extensively characterized in epithelial cells, where the Chlamydia entry-vacuoles avoid fusion with host-cell lysosomes, the cellular immune response has received less attention. Moreover, despite the abundant presence of dendritic cells (DC) in the sites of infection, the interaction between Chlamydia and DC has never been studied. We observe that DC kill Chlamydia trachomatis and Chlamydia psittaci. The chlamydiae are internalized by the DC in a nonspecific manner through macropinocytosis, and the macropinosomes fuse subsequently with DC lysosomes expressing MHC class II molecules. The interaction induces maturation of the DC, since presentation of an exogenous Ag is severely inhibited after a 1-day incubation, although chlamydial Ags are still presented and recognized by Chlamydia-specific CD4+ T cells. Thus, DC most likely play a role in initiating the T cell response in vivo and could potentially be used in adoptive transfer therapies to vaccinate against Chlamydia.

The derivation and characterization of stromal cell lines from the bone marrow of p53-/- mice: new insights into osteoblast and adipocyte differentiation

We have derived a series of clonal cell lines from the bone marrow of p53-/- mice that represent different stages of osteoblast and adipocyte differentiation. All cell lines show indefinite growth potential (>300 population doublings) and have generation times of 12-20 h. These cell lines have been grouped into three categories. The least mature clones are heterogeneous and appear to contain a subpopulation of stem cells, which can spontaneously generate foci that contain either adipocytes or mineralizing osteoblasts. The second category of clones are homogeneous and clearly correspond to mature osteoblasts because they express high levels of the anticipated osteoblastic markers in a stable fashion and cannot differentiate into adipocytes even in the presence of inducers. The clones in the third category are the most unique. Initially they appeared to correspond to mature osteoblasts because they express alkaline phosphatase in a homogeneous manner, secrete type I collagen, show a significant cyclic adenosine monophosphate response to parathyroid hormone, secrete osteocalcin, and mineralize extensively after only 4-7 days. However, in contrast to the mature osteoblasts, these clones can be induced to undergo massive adipocyte differentiation, and this differentiation is accompanied by the complete loss of expression of all osteoblastic markers except alkaline phosphatase. These observations indicate that some cells that have acquired all of the characteristics of mature osteoblasts can be diverted to the adipocyte pathway. Further characterization of these clones may be particularly relevant to osteoporotic conditions where increased adipocyte formation appears to occur at the expense of osteoblast formation.

Preoperative perfusion of bypassed ileum does not improve postoperative function

This study evaluated whether twice daily isotonic perfusion of the bypassed ileum for six weeks would enhance its motor activity and its absorption of fluids, electrolytes, and vitamin B12. The study also determined if patients undergoing perfusion had improved bowel function and decreased hospital stay after ileostomy closure. Following proctocolectomy, ileal pouch-anal canal anastomosis, and diverting loop ileostomy, six patients self-infused an isotonic solution (sucrose and sodium chloride) into the bypassed ileum twice daily, while seven patients did not (controls). Two months following proctocolectomy, and just prior to ileostomy closure, a manometric catheter assembly was placed into the unused distal ileum via the stoma and the distal ileum perfused with an isotonic sodium chloride solution for 3 hr during fasting and 3 hr after a meal. Absorption was measured, single and clustered pressure waves were identified, and a motility index was calculated. Water absorption, motility index, and cluster parameters did not improve in perfused patients compared to controls during fasting or after a meal, nor did perfused patients have improved vitamin B12 absorption. The perfused patients also did no better clinically following ileostomy takedown; the onset of bowel movements, their frequency, time to tolerate a diet, and hospital stay were similar to controls. We conclude that six weeks of twice daily isotonic perfusion did not improve motor activity or water, electrolyte, and vitamin B12 absorption in the bypassed distal ileum after proctocolectomy, ileal pouch-anal canal anastomosis, and loop ileostomy. The perfusion also did not improve bowel function after ileostomy takedown.

Identification of homing receptors that mediate the recruitment of CD4 T cells to the genital tract following intravaginal infection with Chlamydia trachomatis

Murine genital infection induced with the mouse pneumonitis biovar of Chlamydia trachomatis (MoPn) elicits a short-lived protective immunity mediated primarily by Th1 CD4 cells. To understand the development of local cell-mediated immunity against C. trachomatis infection, we investigated the mechanism(s) which mediates CD4 lymphocyte migration to the genital mucosa by identifying molecules that could support this process. We found that primarily CD4 cells were recruited to the genital tract (GT) during primary and challenge MoPn infection. Peak levels were found 21 days after primary inoculation (15.4% +/- 2.7%) and 7 days (31.3% +/- 8.5%) after challenge but diminished after resolution of infection. The CD4 cells appeared to be recruited to the GT in response to infection since these cells expressed the profile of activated, or memory, cells. We also observed up-regulation of homing receptors containing LFA-1 (CD11a) and alpha4 (CD49d) on GT CD4 cells over the course of infection. Furthermore, the mucosal homing receptor chain, beta7, but not the peripheral homing receptor chain beta1 (CD29), was detected on GT CD4 cells. MoPn-infected GT tissue expressed the endothelial cell ligands vascular cell adhesion molecule 1 (VCAM-1), intracellular adhesion molecule 1 (ICAM-1), and mucosal vascular addressin cell adhesion molecule 1 (MAdCAM-1), which correspond to the homing receptors on GT CD4 cells. Interestingly, VCAM-1 and MAdCAM-1 were not expressed in the GTs of uninfected mice but were temporarily induced following infection, indicating that expression of endothelial ligands in the GT are regulated by chlamydial infection. These data suggest that recruitment of CD4 cells to the GT is mediated through LFA-1:ICAM-1 and alpha4beta7:MAdCAM-1-VCAM-1 interactions.

Use of an ileal Roux limb to prevent the Roux stasis syndrome

The aim of this study was to determine whether the use of an ileal Roux limb, rather than a jejunal Roux limb, would prevent the Roux stasis syndrome that can occur after Roux gastrectomy. An ileal Roux limb was constructed in eight dogs and anastomosed to the gastric remnant after distal hemigastrectomy. Flow of chyme through the jejunum was preserved via an ileojejunostomy and a jejunoileostomy. Six dogs with distal gastrectomy and a conventional Roux gastrojejunostomy served as a control group. Chronic enteric recording electrodes and intraluminal, open-tipped pressure catheters were implanted in all dogs. After recovery, the electrical activity and motility of the Roux limbs and the rates of gastric emptying of liquids and solids were measured. Dogs with a Roux gastroileostomy had a slower frequency of pacesetter potentials in the Roux limb, a greater Roux motility index, and a faster rate of gastric emptying of liquids and solids than did dogs with a Roux gastrojejunostomy. Stomal ulcers, however, developed in seven of the eight ileal Roux limbs but in none of the jejunal Roux limbs. It was concluded that Roux gastroileostomy does ameliorate the Roux stasis syndrome, but there is a greater risk of stomal ulceration in the limb.

Ileal pouch-anal canal anastomosis for familial adenomatous polyposis: early and late results

OBJECTIVE

The objective was to review the early and late results of ileal pouch-anal anastomosis (IPAA) done for patients with familial adenomatous polyposis (FAP).

SUMMARY BACKGROUND DATA

Patients with FAP will have colorectal adenomas develop and die of colorectal cancer if left untreated. Ileal pouch-anal anastomosis removes all disease-bearing mucosa while preserving transanal passage of stools.

METHODS

Between 1981 and 1994, 187 patients with FAP, 11 to 59 years of age with a mean follow-up of 60 months (range, 5-170 months) had proctocolectomy and IPAA at Mayo Medical Center in Rochester, Minnesota. All patients had a proximal anal canal mucosal excision and a hand-sewn anastomosis of the pouch to the anal canal at the dentate line. A temporary ileostomy was used in 85% of the patients.

RESULTS

No early postoperative deaths occurred, although two patients died later of metastatic colorectal carcinoma present at their initial operation. More important, no patient had a new cancer develop after IPAA. The overall morbidity after operation was 24%, with small bowel obstruction being the most common complication (13%). Patients had four bowel movements/24 hours and good fecal control, which continued during follow-up.

CONCLUSIONS

The IPAA eradicates the risk of colorectal cancer in patients with FAP. It can be performed with low mortality, acceptable morbidity, and good functional results over the long term.

Fas and Fas ligand enhance the pathogenesis of experimental allergic encephalomyelitis, but are not essential for immune privilege in the central nervous system

Mutations of CD95 and CD95L, lpr and gld, respectively, are associated with spontaneous autoimmune disease and alteration of immune privilege. In lpr or gld animals these processes would be expected to exacerbate experimental allergic encephalomyelitis (EAE), an animal model of the autoimmune demyelinating disease multiple sclerosis. However, here we show that the lpr and gld mutations did not overcome the MHC-defined limits of disease and, surprisingly, did not exacerbate the pathology of EAE on a sensitive haplotype. In fact, the mutations dramatically ameliorated clinical signs of EAE without affecting the development of a Th1 response or inflammatory cell infiltration into the central nervous system. Fewer apoptotic cells were detected in inflammatory lesions of lpr mice than in wild-type lesions of similar severity. Our results indicate that CD95L is not an instrumental component of immune privilege in the central nervous system, and that functional CD95 and CD95L are important for the progression of clinical disease.