CXCL13 expression in Chlamydia trachomatis infection of the female reproductive tract

Chlamydia trachomatis is the most common cause of acute salpingitis worldwide. The socioeconomic impact of sexually transmitted infections (STI) caused by C. trachomatis is considerable. The purpose of this study was to investigate secretion of a unique chemokine, CXCL13, during the inflammatory process in human fallopian tube tissue in response to infection with C. trachomatis. We employed two models for our experiments: archived fallopian tube paraffin sections from known cases of salpingitis of unknown etiology and human fallopian tube organ culture established from fresh fallopian tube biopsies subsequently infected in vitro with C. trachomatis serovar E. We used immunohistochemistry, microarray analysis and cytometric bead array to study these specimens. In both models, we found that the fallopian tissue infected with C. trachomatis expressed CXCL13 and other characteristics of tertiary lymphoid tissue. In addition, we found that CXCL13 was expressed in multiple cell types, including endothelial cells, demonstrating a mechanism for the lymphoid aggregation seen in fallopian tube tissue during salpingitis and infection with C. trachomatis.

Evaluation of plectin-1 immunohistochemical staining in human non-small cell lung cancer

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Background: Plectin-1 (PLEC1), a known scaffolding protein, impacts signaling pathways and has been found to be up-regulated and redistributed to the cell membrane in tumor cells. The redistribution of PLEC1 has shown promise as a novel molecular imaging biomarker in experimental systems. The purpose of this study was to examine the variation of PLEC1 staining in human non-small cell lung cancer (NSCLC). Methods: 142 NSCLC samples from 2001–2003 were obtained from pathology archives and placed into tissue microarray (TMA) format. TMA sections were stained with anti-PLEC1 antibody. A total PLEC1 immunohistochemical (IHC) staining score was obtained by multiplying the intensity of PLEC1 staining, scored 0 through 3, by the percent of tumor cells showing membrane staining, scored 1 for <25%, 2 for 25%-75% and 3 for >75%. The samples were then grouped into low (0–2), intermediate (3–5) or high (6- 9) membrane expression and analyzed for clinical correlations to tumor type and pathological staging. Results: A total of 125 samples were successfully stained for PLEC1. In all NSCLC subgroups, there was variability of PLEC1 staining. Approximately 50% of cases showed intermediate to high staining. There was a trend of lower PLEC1 staining as the tumor stage advanced (p=0.1). There appeared to be no significant variations of PLEC1 staining when compared to gender of the patients. Conclusions: These findings are the first to show that a significant number of human NSCLC exhibit strong expression of PLEC1 in the cell membrane. As this biomarker is being developed for molecular imaging modalities in other tumor types, it may have potential to be of use in the non-invasive detection of disease or therapeutic efficacy monitoring in NSCLC.

[Table: see text]

No significant financial relationships to disclose.

Renal failure in myelomatosis

Renal failure is a common presenting feature in myelomatosis. This review offers a practical means for classifying renal failure in this disease. Three groups are identified: (1) those patients whose renal failure improves or is stable when they are maintained on a high fluid intake; (2) the minority of patients whose renal failure progresses despite high fluid intake; and (3) those patients who are fluid-intolerant due to oliguric renal failure or congestive cardiac failure. The difference between groups 1 and 2 is not simply due to differences in response to chemotherapy, for many group-1 patients achieve improvement in renal function without or before loss of light chain proteinuria. It is concluded that all patients with myelomatosis with excess monoclonal free light chain proteinuria are at risk from developing renal failure of the type associated with group 1. The chances of them doing so are diminished if they maintain a high fluid intake. Group 2 encompasses a range of conditions not all of which are clearly defined. There is generally a poor correlation between the physical characteristics of light chains and the presence of group-2 renal failure.

Synergistic effects of clinically achievable concentrations of 12-O-tetradecanoylphorbol-13-acetate in combination with all-trans retinoic acid, 1alpha,25-dihydroxyvitamin D3, and sodium butyrate on differentiation in HL-60 cells

Our recent studies demonstrated that 12-O-tetradecanoylphorbol-13-acetate (TPA) has pharmacological activity for the treatment of acute myelocytic leukemia patients. In the present study, we investigated the potential synergistic effect of all-trans retinoic acid (RA), 1alpha,25-dihydroxyvitamin D3 (VD3), and sodium butyrate (NaB) on TPA-induced differentiation in HL-60 human promyelocytic leukemia cells. The cells were treated once with these agents for 48 h or treated every 24 h for 96 h. Treatment of HL-60 cells once with TPA, RA, VD3, or NaB for 48 h resulted in concentration-dependent growth inhibition and cell differentiation. At clinically achievable concentrations, TPA (0.16 nM) increased the number of adherent cells and RA (0.1-1 microM) increased the number of nitroblue tetrazolium (NBT)-positive cells. The combinations of TPA (0.16 nM) with RA (0.1-1 microM), VD3 (1 nM), or NaB (100 microM) for 48 h synergistically increased differentiation as measured by the formation of adherent cells (P < or = 0.01). Moreover, cells treated with various combinations of low concentrations of TPA, RA, VD3, and NaB every 24 h for 96 h resulted in a further decrease in cell growth and an increase in differentiation. At clinically achievable concentrations, the strongest stimulation of differentiation was achieved in cells treated with a "cocktail" that combined TPA, RA, VD3, and NaB. The synergistic effect of combinations of TPA with RA or NaB at clinically effective concentrations on HL-60 cell differentiation suggests that the combination of these agents may improve the therapeutic efficacy of TPA for the treatment of acute promyelocytic leukemia (APL) patients. A differentiation "cocktail" that combines TPA, RA, VD3, and NaB may provide an even more effective strategy for improving the therapeutic efficacy of TPA and RA.

Prediction of retention in micellar electrokinetic chromatography from solute structure. 1. Sodium dodecyl sulfate micelles

Like other chromatographic techniques, retention factor, k, in micellar electrokinetic chromatography (MEKC) is directly related to solute partition coefficient and the chromatographic phase ratio as k = Kphi. Unlike conventional chromatography, however, the phase ratio and partition coefficient can be accurately determined in MEKC for a given micellar pseudostationary phase. This means that retention factor in MEKC can be predicted for solutes with known micelle-water partition coefficients without any prior experimentation. In this paper, the use of this simple relationship for prediction of retention behavior in MEKC is examined. The principle of additivity of functional group contribution to partitioning is used to calculate the micelle-water partition coefficient, Kmw, for SDS micellar pseudophase. The micellar substituent constants for 20 functional groups (training set) were determined. Using these substituent constants, the Kmw and retention factors for a group of 80 neutral solutes (test set) were predicted. The linear plot of predicted versus observed log k had an R2 = 0.97 and a slope equal to 1.01. It is shown that the retention times (thus chromatograms) in MEKC can be predicted from the calculated retention factors after only one initial experiment to measure teo and t(mc) under the experimental conditions.

Chlamydia trachomatis infection induces mucosal addressin cell adhesion molecule-1 and vascular cell adhesion molecule-1, providing an immunologic link between the fallopian tube and other mucosal tissues

The development of a protective vaccine against the sexually transmitted disease caused by Chlamydia trachomatis may prevent complications associated with insidious infection. Vaccination via the vaginal route may not be practical, and other routes should be investigated. To this end, the adhesion molecules induced on the fallopian tube endothelium during infection with C. trachomatis were characterized. Adhesion molecules were identified in fallopian tube biopsy specimens cultured with 5 x 10(6) infection-forming units of C. trachomatis serovar E. Frozen sections were prepared from these tissues and were stained by immunohistochemical techniques. Infection with live, but not UV-inactivated, C. trachomatis induced a significant increase in levels of vascular cell adhesion molecule-1 and the mucosal addressin cell adhesion molecule-1 but not of other adhesion molecules. Therefore, infection with C. trachomatis induces adhesion molecules that are associated with other mucosal tissues and inflammatory sites, which suggests that mucosal routes of immunization may be effective.

Bile acid absorption after near-total proctocolectomy in dogs: ileal pouch vs. jejunal pouch-distal rectal anastomosis

Bile acid malabsorption is often present in patients after near-total proctocolectomy and ileal pouch-anal canal anastomosis, suggesting ileal dysfunction. Experiments were performed in dogs to compare bile acid absorption after a modified procedure, in which a jejunal pouch was interposed between the terminal ileum and the distal rectum, with that after a conventional ileal pouch operation. Fecal bile acid output (equivalent to hepatic bile acid biosynthesis) and composition were determined by gas chromatography/mass spectrometry in five jejunal pouch dogs and in five ileal pouch dogs more than 6 months after operation. Fecal bile acid output in the jejunal pouch dogs (mean +/- standard deviation) was 215 +/- 59 mg/day (10.1 +/- 2.7 mg/kg-day), a value similar to that obtained in the ileal pouch dogs (261 +/- 46 mg/day [12.8 +/- 3.1 mg/kg-day]; P >0.05). These values were also similar to those reported by others for healthy unoperated dogs, indicating that increased bile acid biosynthesis occurring in response to bile acid malabsorption was not present. Fecal bile acids in pouch dogs were completely deconjugated and extensively 7-dehydroxylated (jejunal pouch = 90.4% dehydroxylated; ileal pouch = 88.6% +/- 6.6% dehydroxylated) and consisted predominantly of deoxycholic acid derivatives. We conclude that when either a jejunal pouch or an ileal pouch is used as a rectal substitute in dogs, an anaerobic pouch flora develops that efficiently deconjugates and dehydroxylates bile acids, rendering them membrane permeable. The resultant passive absorption of unconjugated bile acids appears to compensate for any loss of active ileal absorption of conjugated bile acids, and bile acid malabsorption does not occur.

Tetrahydrobiopterin levels regulate endothelial cell proliferation

Vascular abnormalities, including altered angiogenesis, are major factors contributing to the morbidity and mortality of diabetes. We hypothesized that impaired angiogenesis in diabetes results from decreased tetrahydrobiopterin (BH4)-dependent synthesis of nitric oxide (NO) by endothelial cells (EC). To test this hypothesis, we utilized EC from spontaneously diabetic BB (BBd) and nondiabetes-prone BB (BBn) rats to investigate the link between BH4 and EC proliferation. There were significant decreases in the proliferation rate and expression of proliferating cell nuclear antigen in BBd versus BBn EC, with no evidence of apoptosis in either group. Sepiapterin (a precursor of BH4 via the salvage pathway) increased BH4 synthesis and enhanced proliferation of BBd EC. The stimulating effect of sepiapterin on EC proliferation was attenuated by NG-monomethyl-L-arginine, a NO synthase inhibitor. Reducing BH4 concentrations in BBn EC caused a decrease in proliferation, which was attenuated by a long-acting NO donor. Our results suggest that BH4 levels regulate proliferation of normal EC and that a BH4 deficiency impairs NO-dependent proliferation of BBd EC.

Characteristics and evolution of extraintestinal manifestations associated with ulcerative colitis after proctocolectomy

AIMS

Describe the characteristics of extraintestinal manifestations complicating ulcerative colitis present preoperatively and determine their evolution after surgery.

METHODS

Between 1976 and 1986, 281 patients with ulcerative colitis exhibiting one or more extraintestinal manifestations (EIM) before either IPAA (n = 147), Brooke ileostomy (n = 71), Kock pouch (n = 48) or ileorectostomy (n = 15) were assessed retrospectively. The clinical evolution of each manifestation was classified as having disappeared, improved, remained unchanged or aggravated postoperatively. An efficacy index was designed to assess the ratio of the number of cases cured or improved over the number of cases unchanged or aggravated. The relationship between EIM and gender, age, duration of disease and the type of surgery was also ascertained.

RESULTS

433 EIM were observed in 281 patients. The most common were arthralgias of the large joints (n = 146), of the sacroiliac joint (n = 59) and the small joints (n = 51). In comparison to patients without EIM having received the same operation during the same period of time, EIM were seen more often in women, younger patients, than those with longer duration of disease and the ileoanal anastomosis group. 60% had only one EIM at a time. Based on the efficacy index, thromboembolic accidents and erythema nodosum were the most commonly cured or improved. Ocular manifestations and primary sclerosing cholangitis were unaffected. The other EIM responded favorably but variably with improvement in two thirds of patients. The presence of a rectal remnant (IRA) or ileal reservoir did not affect the evolution of the EIM.

CONCLUSIONS

Thromboembolic complications which are life-threatening, erythema nodosum and arthralgia of the small and large joints which impair quality of life, benefited the most from proctocolectomy. Those conditions may be considered preoperatively when making the decision for surgery.

Chlamydia trachomatis infection does not enhance local cellular immunity against concurrent Candida vaginal infection

Although Th1-type cell-mediated immunity (CMI) is the predominant host defense mechanism against mucosal Candida albicans infection, CMI against a vaginal C. albicans infection in mice is limited at the vaginal mucosa despite a strong Candida-specific Th1-type response in the draining lymph nodes. In contrast, Th1-type CMI is highly effective against an experimental Chlamydia trachomatis genital tract infection. This study demonstrated through two independent designs that a concurrent Candida and Chlamydia infection could not accelerate or modulate the anti-Candida CMI response. Together, these results suggest that host responses to these genital tract infections are independent and not influenced by the presence of the other.

Development of dendritic cells in culture from human and murine thymic precursor cells

The earliest T-precursor population in the adult murine thymus can give rise to dendritic cells (DC) in culture if stimulated with a cocktail of cytokines that includes interleukin (IL)-3, but not with cytokine mixes based on granulocyte-macrophage colony stimulating factor (GM-CSF), normally used to generate myeloid-derived DC. This and other evidence led to the proposal that two different lineages of DC exist, one lymphoid-related and the other myeloid-related. To determine whether this selective response to cytokines was restricted to murine DC, early human thymic T-precursors were isolated and their capacity to generate DC in response to various cytokines directly compared to their murine counterparts. In contrast to cultures of murine thymic precursors, CD34+CD1a- lineage marker negative (Lin-) precursor cells from the human thymus proliferated and generated DC with both the IL-3-containing cytokine mix lacking GM-CSF and with GM-CSF based cytokine mixes. These CD34+CD1a-Lin- human precursor cells also gave rise to NK cells under appropriate culture conditions, but produced no granulocyte, monocyte, eosinophil, megakaryocyte or erythroid cells in standard soft-agar colony-forming cell assays. Thus, although apparently lymphoid-restricted, the human thymic DC precursors responded to the myeloid factor GM-CSF as well as to the cytokines selective for murine lymphoid-related DC.

Enhancing release of peptide YY after near-total proctocolectomy: jejunal pouch vs. ileal pouch-distal rectal anastomosis

Reconstructing the enteric tract after near-total proctocolectomy by interposing a jejunal pouch between the distal ileum and the distal rectum slows small intestinal transit and decreases the number of stools per day compared to a conventional ileal pouch-distal rectal reconstruction. Our hypothesis was that the jejunal pouch operation brings about these results by protecting the ability of the ileal mucosa to secrete peptide YY, thus augmenting the hormonal ileal brake on small intestinal transit and decreasing the stool frequency. In five jejunal pouch dogs and five ileal pouch dogs, more than 6 months after the operation, serum peptide YY concentrations were determined before and at 30-minute intervals for 180 minutes after a standard meal. Fasting serum concentrations of peptide YY, measured by radioimmunoassay, were greater in jejunal pouch dogs (mean +/- SEM, 1340 +/- 143 pg/ml) than in ileal pouch dogs (804 +/- 52 pg/ml; P < 0.01). Postprandial peptide YY concentrations in jejunal pouch dogs were also greater at 30 minutes (jejunal pouch = 1524 +/- 131 pg/ml, ileal pouch = 913 +/- 67 pg/ml; P = 0.01) and 60 minutes after the meal (jejunal pouch = 1723 +/- 250 pg/ml, ileal pouch = 1001 +/- 70 pg/ml; P = 0.05) and peaked sooner (jejunal pouch = 81 +/- 17 minutes, ileal pouch = 147 +/- 12 minutes; P = 0.01). We concluded that the jejunal pouch operation results in greater ileal fasting and postprandial secretion of peptide YY than the ileal pouch operation. The greater release may account, in part, for the slower small bowel transit and decreased number of stools after the jejunal pouch operation.

Dendritic cells derived from multiple myeloma patients efficiently internalize different classes of myeloma protein

Myeloma protein is a unique tumor antigen that can be used to devise tumor-specific vaccination strategies. As dendritic cells (DCs) are extremely potent at inducing T-cell responses, clinical protocols have been designed using myeloma protein-pulsed DCs to elicit anti-tumor cell responses in vivo. To optimize antigen pulsing of DCs, we investigated mechanisms of antigen uptake and evaluated various laboratory parameters including class of myeloma protein, antigen exposure time, and DC maturational stage.DCs were generated by culturing peripheral blood stem cells from myeloma patients in granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4). Myeloma proteins were labeled with fluorescein isothiocyanate (FITC) and internalization of protein by DCs was measured by flow cytometry.IgG, IgA, and free-kappa light chain myeloma proteins were all rapidly internalized by DCs in a time-dependent fashion. Maturation of DCs with tumor necrosis factor-alpha (TNF-alpha) resulted in diminished uptake. Endocytosis of myeloma protein by DCs was primarily mediated by fluid-phase macropinocytosis based on morphology, nonsaturable uptake kinetics, and sensitivity to drugs that inhibit membrane ruffling. Pulse-chase experiments revealed that the majority of internalized myeloma protein disappeared within 4 hours but was retained in the presence of chloroquine, indicating antigen processing had occurred. Cultured DCs from myeloma patients are functional and can efficiently endocytose different classes of myeloma protein by the mechanism of macropinocytosis. This demonstrates the feasibility of using all classes of myeloma protein for producing DC vaccines, and defines culture conditions for optimizing antigen loading of DCs for induction of anti-myeloma responses.

Glucosamine inhibits inducible nitric oxide synthesis

Glucosamine is widely used in Europe for treatment of arthritis in humans. Based on recent findings that excess production of nitric oxide (NO) by inducible NO synthase (iNOS) mediates the pathogenesis of arthritis, we hypothesized that glucosamine may inhibit NO synthesis. To test this hypothesis, we used an in vivo rat model of lipopolysaccharide (LPS)-induced inflammation. Intravenous administration of d-glucosamine (0.5 mmol/kg) 6 h before, at the time of, and 6 h after intraperitoneal LPS injection (1 mg/kg) decreased urinary excretion of nitrate by 31 and 48%, respectively, at days 1 and 2 post LPS administration. When cultured macrophages were treated with LPS (1 microg/ml) to induce iNOS expression, addition of 0.1, 0.5, 1, and 2 mM d-glucosamine decreased NO production by 18, 38, 60, and 89%, respectively. Glucosamine had no effect on cellular arginine, NADPH or tetrahydrobiopterin concentrations, but dose-dependently suppressed iNOS protein expression. Similar decreases in iNOS protein occurred in spleen, lung, and peritoneal macrophages of glucosamine-treated rats. These studies demonstrate that glucosamine is a novel inhibitor of inducible NO synthesis via inhibition of iNOS protein expression, and provide a biochemical basis for the use of glucosamine in treating chronic inflammatory diseases such as arthritis.

Characterization of the binding site for a novel class of noncompetitive alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonists

The alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor is an ionotropic glutamate receptor that mediates fast excitatory synaptic transmission throughout the central nervous system. In addition to the glutamate binding site, allosteric modulatory sites on the receptor are inferred from the ability of synthetic compounds to affect channel function without interaction with the glutamate binding site. We have identified a novel class of potent, noncompetitive AMPA receptor antagonists typified by CP-465, 022 and CP-526,427. The latter compound was radiolabeled and used to elucidate the pharmacology of one allosteric modulatory site. [(3)H]CP-526,427 labels a single binding site in rat forebrain membranes with a K(d) value of 3.3 nM and a B(max) of 7.0 pmol/mg of protein. The [(3)H]CP-526,427 binding site does not seem to interact directly with the glutamate binding site but overlaps with that for another class of AMPA receptor antagonists, the 2,3-benzodiazepines. This binding site is distinct from that for the antagonist Evans blue and for several classes of compounds that modulate AMPA receptor desensitization. These results indicate the existence of at least two physically distinct allosteric sites on the AMPA receptor through which channel activity or desensitization is modulated.

Modulation of tumor angiogenesis by stem cell factor

Mast cells accumulate within solid tumors and can release many angiogenic factors, suggesting that they may modulate vascularization of tumors. Stem cell factor (SCF) stimulates mast cell migration, proliferation, and degranulation and therefore may influence mast cell behavior within tumors. We investigated the contribution of SCF to tumor angiogenesis by manipulating its level in mammary tumors. Sense or antisense cDNA fragments of rat SCF were ligated into an episomal expression vector. Ethylnitrosourea-induced rat mammary tumor cell lines were transfected with vector containing either control (no insert, C-P), sense (S-P), or antisense (AS-P) SCF DNA. The functional nature of the transfectants was confirmed by measuring SCF in cell lysates and conditioned media. Immunohistochemical analysis of the tumors induced in Berlin-Druckrey rats by these transfected cells demonstrated that mast cell number and microvascular density were significantly higher in S-P tumors and significantly lower in AS-P tumors, compared with C-P tumors. The expression of von Willebrand factor, an endothelial cell marker, showed a similar pattern. AS-P tumors were significantly smaller than either C-P or S-P tumors. These data suggest that SCF modulates tumor growth and angiogenesis via the involvement of mast cells.

Ten and more years after vertical banded gastroplasty as primary operation for morbid obesity

Long-term follow-up (>10 years) after vertical banded gastroplasty (VBG) is almost nonexistent. The aim of this study was to determine long-term outcome after VBG in a group of 71 patients studied prospectively. Seventy-one consecutive patients with morbid obesity (54 women and 17 men; mean age 40 years [range 22 to 71 years]) underwent VBG from 1985 to 1989 and were followed prospectively. Follow-up was obtained in 70 (99%) of the 71 patients. Weight (mean +/- standard error of the mean) preoperatively was 138 +/- 3 kg and decreased to 108 +/- 2 kg 10 or more years postoperatively. Body mass index decreased from 49 +/-1 to 39 +/- 1. Only 14 (20%) of 70 patients lost and maintained the loss of at least half of their excess body weight with the VBG anatomy. Vomiting one or more times per week continues to occur in 21% and heartburn in 16%. Fourteen patients have undergone conversion from VBG to Roux-en-Y gastric bypass (11 patients) or other procedures (3 patients) because of a combination of inadequate weight loss in 13 patients, gastroesophageal reflux in five, and frequent vomiting in four. Only 26% of patients after VBG have maintained a weight loss of at least 50% of their excess body weight; 17% underwent bariatric reoperation with good results. Thus VBG is not an effective, durable bariatric operation.

Expression of mucosal homing receptor alpha4beta7 is associated with enhanced migration to the Chlamydia-infected murine genital mucosa in vivo

The CD4 T helper cell type 1 (Th1) response is essential for the resolution of chlamydial genital infection in mice. However, not all Th1 clones are equally protective in eradicating the infection. Since oral immunization regimens produce protective immunity, we evaluated the role of the mucosa-associated homing receptor, alpha4beta7, in trafficking to the genital mucosa. Using a panel of CD4, Th1 cell lines and clones, we compared the lymphocyte homing patterns of a Chlamydia-specific, protective clone (P-MoPn), a nonprotective clone (N-MoPn), and a keyhole limpet hemocyanin (KLH)-specific cell line (KLH-1). T cells were labeled with the fluorescent dye PKH-26, adoptively transferred into Chlamydia-infected mice, and monitored at different time points throughout the course of a genital infection. We found that clones P-MoPn and N-MoPn migrated to similar extents to the genital tract and in significantly greater numbers than the KLH-specific T-cell line. Both clones and the KLH-1 line expressed similar levels of the adhesion molecules alpha4, beta1, CD44, and CD11a. However, clones P-MoPn and N-MoPn expressed higher levels of the mucosal homing receptor, alpha4beta7. Also, clones P-MoPn and N-MoPn but not the KLH-1 line migrated to the mesenteric lymph node, suggesting a mucosal recirculation pattern. Moreover, blocking alpha4beta7 adhesion interaction in vivo significantly reduced the recruitment of P-MoPn but not KLH-1 to the genital tract. These findings show that the mucosal homing receptor alpha4beta7 is utilized by a subset of CD4 cells during migration to the Chlamydia-infected genital tract.

Characterization of lymphocyte response in the female genital tract during ascending Chlamydial genital infection in the guinea pig model

It is well known that pathology caused by chlamydial infection is associated closely with the host response to the organism and that both innate and adaptive host responses contribute to tissue damage. While it is likely that the organism itself initiates the acute inflammatory response by eliciting cytokine and chemokine production from the host cell, the adaptive response is the result of activation of the cell-mediated immune response. While there are several studies describing the nature of the pathologic response in primate, guinea pig, and murine models, there is less information on the kinetics of the CD4 and CD8 response following primary and challenge infections. In this study, we have quantified by flow cytometry the mononuclear cell response to genital infection with the agent of guinea pig inclusion conjunctivitis in the cervix, endometrium, and oviducts at various times following a primary intravaginal infection and after a challenge infection. Tissues from individual animals were assessed for cells expressing CD4, CD8, or Mac-1 and for B cells. Peak responses of each subset occurred 10 to 14 days after a primary infection. The number of Mac-1-expressing cells in each tissue site was found to be dependent on the size of the inoculating dose of chlamydiae. The responses of each cell type were generally stronger in the cervix than in the upper genital tract. In contrast to the murine model but consistent with the primate models, there were equal numbers of CD4 and CD8 cells present in the infiltrates. Twenty-one days after challenge infection, which was performed 50 days after the primary infection, there was a significant increase in the number of CD4, CD8, and B cells in the oviduct compared to the number of these cells at the same time after a primary infection, providing clear cellular evidence for a cell-mediated immune pathologic response.

Impaired nitric oxide production in coronary endothelial cells of the spontaneously diabetic BB rat is due to tetrahydrobiopterin deficiency

Endothelial cells (EC) from diabetic BioBreeding (BB) rats have an impaired ability to produce NO. This deficiency is not due to a defect in the constitutive isoform of NO synthase in EC (ecNOS) or alterations in intracellular calcium, calmodulin, NADPH or arginine levels. Instead, ecNOS cannot produce sufficient NO because of a deficiency in tetrahydrobiopterin (BH(4)), a cofactor necessary for enzyme activity. EC from diabetic rats exhibited only 12% of the BH(4) levels found in EC from normal animals or diabetes-prone animals which did not develop disease. As a result, NO synthesis by EC of diabetic rats was only 18% of that for normal animals. Increasing BH(4) levels with sepiapterin increased NO production, suggesting that BH(4) deficiency is a metabolic basis for impaired endothelial NO synthesis in diabetic BB rats. This deficiency is due to decreased activity of GTP-cyclohydrolase I, the first and rate-limiting enzyme in the de novo biosynthesis of BH(4). GTP-cyclohydrolase activity was low because of a decreased expression of the protein in the diabetic cells.

Collodion baby: a case report

A case report of a collodion baby born in a community hospital who was diagnosed, stabilized, and transferred for dermatologic management is presented. Differential diagnosis based on cornification disorder phenotypes is outlined. The initial stabilization, management, and nursing considerations of the infant with impaired barrier function of the skin are outlined.

The jejunal pouch as a rectal substitute after proctocolectomy

Our hypothesis was that a jejunal pouch used as a rectal substitute after proctocolectomy would slow enteric transit, delay defecation, and decrease stool frequency compared to an ileal pouch so used. Twelve dogs underwent proctocolectomy; six had a jejunal pouch-distal rectal anastomosis and six had an ileal pouch-distal rectal anastomosis. After recovery, postprandial mouth-to-anus transit was slower in jejunal pouch dogs (253 +/- 18 minutes [mean +/- SEM]) than in ileal pouch dogs (112 +/- 7.9 minutes; P <0.05). Moreover, jejunal pouch dogs passed only 4.1 +/- 0.3 stools during the 12 hours after eating, whereas ileal pouch dogs passed 6.3 +/- 0. 9 stools (P <0.05). The mean frequency of proximal ileal pacesetter potentials after feeding was less in jejunal pouch dogs (12 +/- 0.4 cycles/min) than in ileal pouch dogs (16 +/- 0.3 counts/min; P = 0. 01), and jejunal pouches had more action potentials (jejunal = 82% +/- 4.3% of pacesetter potentials had action potentials, ileal = 61% +/- 3.0%; P <0.05). In contrast, gastric emptying and pouch motility, emptying, mucosal integrity, and bacteriologic and histologic properties were similar in the two groups of dogs. We concluded that the jejunal pouch operation slowed enteric transit, delayed defecation, and decreased postprandial stooling compared to the ileal pouch operation.

Differential regulation of CD4 lymphocyte recruitment between the upper and lower regions of the genital tract during Chlamydia trachomatis infection

Genital infection with Chlamydia trachomatis results in both the local recruitment of protective immune responses and an inflammatory infiltrate that may also participate in tubal pathology. As a beginning to understanding the etiology of immune system-mediated tubal pathology, we evaluated the regional recruitment of lymphocyte subsets to different areas of the female genital tract (GT) over the course of a murine infection with the mouse pneumonitis agent of Chlamydia trachomatis (MoPn). Using flow cytometric techniques we found that the CD4 lymphocyte subset was preferentially recruited to the upper GT (oviduct and uterine horn) over the lower GT (cervical-vaginal region) throughout the course of MoPn infection. The influx of CD4 cells also correlated with the expression of endothelial cell adhesion molecules (ECAMs) and in vitro lymphocyte adherence in the upper GT. Interestingly, the expression of ECAMs in the lower GT was not maintained longer than 7 days after infection, even in the presence of viable chlamydiae. Taken together, these data suggest that regulatory mechanisms of lymphocyte recruitment differ between the upper and lower regions of the GT and may influence the clearance of chlamydiae and the development of tubal pathology.

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.