Faecal microbiome in new-onset juvenile idiopathic arthritis.

Alterations in the intestinal microbial flora have been linked with autoimmune diseases. Our objective was to analyse the composition of the faecal microbiome of children with new-onset juvenile idiopathic arthritis (JIA) compared to healthy controls, and to identify specific gut bacteria associated with JIA. Stool samples from patients were taken at the time of diagnosis of JIA. The microbiome profiles of samples of 30 children with JIA (mean age 6.2 years, 22 girls) were analysed with 16S region-based sequencing profiling and compared to the stool samples of healthy controls (n = 27, mean age 5.4 years, 18 girls). The proportion of bacteria belonging to the phylum Firmicutes was significantly lower in children with JIA [21 % (95 % confident interval [CI]: 17-25 %)] compared to controls [33 % (95 % CI: 26-41 %), p = 0.009]. Bacteria belonging to Bacteroidetes were significantly more abundant in JIA [78 % (95 % CI: 74-82 %)] than in control samples [65 % (95 % CI: 57-73 %), p = 0.008]. Shared operational taxonomic units (OTUs) between the groups revealed that genera Actinobacteria and Fusobacteria were present only in JIA patients and Lentisphaerae only in controls. In summary, faecal flora in JIA is characterised by a low level of Firmicutes and an abundance of Bacteroidetes, resembling the aberration reported in type 1 diabetes. We suggest that alterations in the intestinal microbial flora may challenge the mucosal immune system of genetically susceptible subjects predisposing to local proinflammatory cascades, thus contributing to the development of JIA.

Serum endostatin levels are elevated in colorectal cancer and correlate with invasion and systemic inflammatory markers.

BACKGROUND: Endostatin, a fragment of collagen XVIII, is an endogenous angiogenesis inhibitor with anti-tumour functions. However, elevated circulating endostatin concentrations have been found in several human cancers including colorectal cancer (CRC). METHODS: Serum endostatin levels were measured by enzyme-linked immunoassay from a series of 143 patients with CRC and from 84 controls, and correlated with detailed clinicopathological features of CRC, serum leukocyte differential count and C-reactive protein (CRP) levels. RESULTS: Patients with CRC had higher serum endostatin levels than the controls (P=0.005), and high levels associated with age, tumour invasion through the muscularis propria and poor differentiation, but not with metastases. Endostatin levels showed a positive correlation with the markers of systemic inflammatory response and a negative correlation with the densities of tumour-infiltrating mast cells and dendritic cells. Collagen XVIII was expressed in tumour stroma most strikingly in blood vessels and capillaries, and in the muscle layer of the bowel wall. CONCLUSIONS: Elevated endostatin levels in CRC correlate with systemic inflammation and invasion through the muscularis propria. Increased endostatin level may be a result of invasion-related cleavage of collagen XVIII expressed in the bowel wall. The negative correlations between serum endostatin and intratumoural mast cells and immature dendritic cells may reflect angiogenesis inhibition by endostatin.

Histological damage of colonic epithelium is associated with clinical severity and outcome in colectomized critically Ill patients.

BACKGROUND: Severe intestinal mucosal damage and organ failure has been associated in experimental models. Our purpose was to determine whether there is any association between histopathological findings and postoperative mortality among ICU patients undergoing emergency colectomies for various illnesses. METHODS: In a retrospective case control study, total colectomy specimens from 50 patients in a mixed ICU were analysed: 18 had sepsis, 11 vascular operations, and 21 Clostridium difficile colitis. Overall thickness, the width of epithelial defects, and presence of cryptal damage were assessed. Extent of necrosis and amount of neutrophils were separately evaluated in the layers of the colonic wall. Clinical features, including sequential organ failure assessment (SOFA) scores and survival, were registered. RESULTS: The histopathological findings for the three clinical entities were similar, except for the abundance of characteristic pseudomembranes in the Clostridium group. Mucosal height (maximum) showed a negative correlation with SOFA score on admission (ρ = -0.296, P = 0.037), and with preoperative blood lactate level (ρ = -0.316; P = 0.027). The nonsurvivors had wider enterocyte defects (60 vs. 40.8, P = 0.002) and more severe crypt damage (61 vs. 27 %; P = 0.024) than the survivors. CONCLUSIONS: The histopathological damage involves all layers of the colon wall among ICU patients being largely similar in sepsis, C. difficile infection, and ischemia after vascular operations. Mucosal epithelial damage is associated with clinical severity of the illness and mortality.

Toll-like receptor 5 (TLR5) expression is a novel predictive marker for recurrence and survival in squamous cell carcinoma of the tongue.

BACKGROUND: Toll-like receptor 5 (TLR5) is an immune receptor recognising bacterial flagellin. Activation of TLR5 results in cancer invasion and cytokine release. As certain bacteria have been linked to oral cancer, we wanted to study TLR5 expression in oral tongue squamous cell carcinoma (OTSCC). METHODS: Samples from 119 patients with OTSCC were obtained, including 101 samples of adjacent normal lingual mucosa. The TLR5 histoscore (0-300) was assessed semiquantitatively by immunohistochemistry in a blinded manner. RESULTS: Toll-like receptor 5 was expressed in 84 normal epithelia and 118 cancer samples. Expression of TLR5 was increased in cancer when compared with normal lingual epithelium (median histoscore 15 vs 135). In cancer, higher TLR5 was associated with age of >70 years at the time of diagnosis, female gender and disease recurrence. No association between TLR5 expression and tumour grade, stage or treatment was found. In multivariate analysis, TLR5 was an independent predictor of cancer mortality (hazard ratio (HR) 3.587, 95% confidence interval (CI) (1.632-7.882)) and disease recurrence (HR 4.455, 95% CI (2.168-9.158)). CONCLUSION: Toll-like receptor 5 has a previously undescribed role in the pathophysiology of OTSCC and might represent a link between bacteria and cancer. It could be a useful marker for predicting recurrence or survival of OTSCC patients.

Detailed analysis of inflammatory cell infiltration in colorectal cancer.

BACKGROUND: Higher-grade inflammatory infiltrate is a promising marker for better prognosis in colorectal cancer (CRC). However, the knowledge on the interrelationships between different inflammatory cells and classifications is fragmentary. METHODS: We analysed the densities of eight types of inflammatory cells in a prospectively recruited group of 117 CRC patients and determined their interrelationships and contributions to Klintrup-Mäkinen (K-M) score of overall peritumoural inflammation. We characterised the inflammatory infiltrate in relation to stage and recurrences in 24-month follow-up. RESULTS: There were high positive correlations between the inflammatory cell densities, with the exception of mast cells and CD1a+ immature dendritic cells. High K-M score associated with high peri- and intratumoural densities of CD3+, CD8+, CD68+, CD83+, and FoxP3+ cells and neutrophils. Advanced stage associated with low K-M score, as well as low CD3+, CD8+, CD83+, and FoxP3+ cell counts, of which low K-M score, low CD3(+) T-cell count, and low FoxP3+ T-cell count were linked to higher recurrence rate. CONCLUSION: The density of CRC inflammatory infiltrate declines as stage advances. Especially, low K-M score and low T-cell counts predict higher recurrence rate. The high positive correlations between the individual inflammatory markers support the value of overall inflammatory reaction scoring.

Decreased expression of protease inhibitor 9, a granzyme B inhibitor, in celiac disease: a potential mechanism in enterocyte destruction and villous atrophy.

The objective of this study was to assess the expression of protease inhibitor 9, a granzyme B inhibitor, in human small intestine, and to evaluate its cytoprotective role in the celiac disease of children. Twelve subjects with untreated celiac disease and thirteen healthy controls were examined by endoscopy. The expression of protease inhibitor 9 was analyzed immunohistochemically from duodenal biopsies and compared to granzyme B expression, apoptosis rate, number of intraepithelial lymphocytes and villus and crypt height data from the biopsies. We discovered that protease inhibitor 9 is expressed in the cytoplasm of the duodenal epithelial cells in the majority of cases. The enterocyte expression of protease inhibitor 9 was lower in celiac disease patients than in controls. Protease inhibitor 9 expression also showed a negative correlation with the number of apoptotic cells, overall density of granzyme B expressing intraepithelial lymphocytes, the height of the crypts and the severity of villous atrophy in duodenum. Therefore, we conclude that the protease inhibitor 9 is constantly expressed in the enterocytes of normal duodenum and the expression is decreased in celiac disease. These findings suggest that protease inhibitor 9 has a role in duodenal homeostasis and in the protection of enterocytes from misdirected granzyme B. Indeed, observed associations of lowered protease inhibitor 9 expression together with increased granzyme B expression, apoptosis rate and severity of villous atrophy suggest that impaired balance between granzyme B mediated cytotoxicity and its inhibition by protease inhibitor 9 forms an important factor in the pathogenesis of villous atrophy in celiac disease.

Stage-dependent alterations of the serum cytokine pattern in colorectal carcinoma.

BACKGROUND: Inflammation contributes to the pathogenesis of colorectal cancer (CRC), and cytokine levels are altered during colorectal carcinogenesis. METHODS: The serum levels of 13 cytokines and their relation to clinical and pathological parameters, and systemic inflammatory response (mGPS, CRP and neutrophil-lymphocyte ratio), were analysed from a prospective series of 148 CRC patients and 86 healthy age- and sex-matched controls. RESULTS: CRC patients had higher serum platelet-derived growth factor, interleukin (IL)-6, IL-7, and IL-8 levels and lower monocyte chemotactic protein-1 (MCP-1) levels than the controls. A logistic regression model for discriminating the patients from the controls - including the five most predictive cytokines (high IL-8, high IL-6, low MCP-1, low IL-1ra, and low IP-10) - yielded an area under curve value of 0.890 in receiver operating characteristics analysis. Serum cytokines showed distinct correlation with other markers of systemic inflammatory response, and advanced CRCs were associated with higher levels of IL-8, IL-1ra, and IL-6. A metastasised disease was accompanied by an orientation towards Th2 cytokine milieu. CONCLUSION: CRC is associated with extensive alterations in serum cytokine environment, highlighting the importance of studying relative cytokine level alterations. Serum cytokine profile shows promise in separating CRC patients from healthy controls but its clinical value is yet to be confirmed.

Altered expression of intestinal human leucocyte antigen D-related and immune signalling molecules in juvenile idiopathic arthritis.

We aimed to study intestinal immune activation status in juvenile idiopathic arthritis (JIA) by assessing intestinal human leucocyte antigen (HLA) class II expression and the mRNA expression levels of the pro- and anti-inflammatory mediators and pattern recognition receptors. HLA-D-related (HLA-DR) expression was assessed using immunohistochemical staining of frozen sections in 11 children with JIA and 17 controls. The gene expression levels of the anti- and proinflammatory cytokines, lymphocyte recognition receptors and pattern recognition receptors were studied with reverse transcription-polymerase chain reaction (RT-PCR) in 14 children with JIA and 12 controls. All subjects had various gastrointestinal (GI) symptoms indicating endoscopic examinations, but eventually were not diagnosed with GI disease. In JIA patients, the expression of HLA-DR was increased in the crypt epithelial cells and in the epithelial basement membrane of the ileum when compared with the controls. Positive HLA-DR staining in the ileal mucosa was associated with the presence of high clinical disease activity of JIA and low mRNA expression of anti-inflammatory mediators, such as forkhead box protein P3 (FoxP3), glucocorticoid-induced tumour necrosis factor receptor-related protein (GITR) and transforming growth factor (TGF)-beta. Low ileal expression of interleukin (IL)-10, TGF-ß, FoxP3, Toll-like receptor 2 (TLR-2) and TLR-4 transcripts correlated significantly with a high clinical disease activity in the JIA patients. The increased HLA-DR expression suggests enhanced intestinal antigen presentation in JIA. A correlation between clinical disease activity and low gene expression of tolerogenic mediators in the ileum supports the hypothesis that a link exists between the gut immune system and JIA.

Heat shock protein expression is low in intestinal mucosa in juvenile idiopathic arthritis: a defect in immunoregulation?

OBJECTIVES: Heat shock proteins (HSPs) are involved in the regulation of inflammation and in the maintenance of mucosal integrity. Their altered expression may be a marker of mucosal inflammation and also contribute to tissue injury. The small intestinal mucosa in children with juvenile idiopathic arthritis (JIA) shows signs of intestinal immune activation, such as increased intraepithelial cytotoxic lymphocyte counts. To further evaluate the characteristics of this immune activation in JIA, we have studied the expression of several HSPs, major histocompatibility complex (MHC) class I-related chain A (MICA), and the heat shock transcription factor 1 (HSF1) in intestinal biopsies from children with JIA. METHODS: We studied 15 patients with JIA. Controls included 13 children without JIA, studied for various gastrointestinal (GI) symptoms, but eventually shown not to have any GI disease. The subjects were examined by endoscopy. The expression of HSP60, HSP70, MICA, and HSF1 was analysed in ileal and duodenal biopsies by using immunohistochemistry. RESULTS: The expression levels of HSP60, MICA, and HSF1 were significantly lower in the duodenal epithelium in the JIA patients compared to the controls. MICA and HSF1 also showed lower expression in the ileal epithelium. The expression of HSP70 did not differ between the groups. CONCLUSIONS: The downregulation of HSP60, MICA, and HSF1 in small intestinal mucosa may indicate that intestinal epithelial cells show immune aberration in JIA. We speculate that the low heat shock response may play a role in the pathogenesis of JIA, interfering with mucosal integrity and local intestinal immunoregulation.

Increase of duodenal and ileal mucosal cytotoxic lymphocytes in juvenile idiopathic arthritis.

OBJECTIVE: Intestinal gamma/delta- intraepithelial lymphocytes (IEL) have increased in children with juvenile idiopathic arthritis (JIA). To further characterise intestinal immune activation in these children, we have quantitated cytotoxic lymphocytes in intestinal mucosa. METHODS: We studied 23 children with JIA suffering from gastrointestinal symptoms with gastroduodenoscopy and colonoscopy. The control children (n=20) had GI-symptoms but eventually shown not to have any significant gastrointestinal disease. Granzyme A (GrA) and Granzyme B (GrB) expressing lymphocytes in the epithelium and lamina propria were counted in immunostained sections of ileal and duodenal biopsies. RESULTS: The number of GrB expressing IELs was increased in duodenal mucosa in patients with JIA. In the ileum the number of both GrB and GrA positive IELs was similarly increased. No significant differences in the counts of the lamina propria GrA or GrB expressing cells were observed. Granzyme expression was not associated with the duration or with the severity of the disease, or with medication. CONCLUSIONS: These observations suggest that lymphocyte cytotoxicity is abnormally increased in the intestinal mucosa in JIA. Since a similar pattern of activation has been seen in food allergy and celiac disease, we speculate that some luminal, possibly a nutritional factor may be involved in JIA as well. Further studies are needed to see whether cytotoxic activation plays any role in the pathogenesis of JIA.

Serrated carcinomas form a subclass of colorectal cancer with distinct molecular basis.

Serrated colorectal carcinomas (CRCs) are morphologically different from conventional CRCs and have been proposed to follow a distinct pathway of CRC formation. Despite studies of single molecular events in this tumor type, the diagnosis of serrated CRC relies on morphology and the putative unique biological character of these tumors has not been established. Here we show that the gene expression profiling of 37 CRCs separated serrated and conventional CRCs into two distinct branches in unsupervised hierarchical clustering (P-value 7.8 x 10(-7)), and revealed 201 differentially expressed genes representing potential biomarkers for serrated CRC. Immunohistochemistry was utilized to verify the key findings in the 37 CRCs examined by expression profiling, and a separate validation set of 37 serrated and 86 conventional CRCs was examined to evaluate the candidate biomarkers in an extended sample material. Ephrin receptor B2, hypoxia-inducible factor 1-alpha and patched appeared as proteins important for genesis of serrated CRC. This study establishes serrated CRCs as a biologically distinct subclass of CRC and represents a step forward in the molecular classification of these cancers. The study also provides a platform to understand the molecular basis of serrated CRC and in long term may contribute to the development of specific treatment options for this tumor type.

IgE cross reactivity between reindeer and bovine milk beta-lactoglobulins in cow's milk allergic patients.

BACKGROUND: Allergic reactions to cow's milk are common in small children. One of the main protein allergens found in cow's milk is beta-lactoglobulin (beta-Lg). Reindeer and bovine milk both contain related beta-Lg proteins, but the allergenicity of reindeer beta-Lg has not previously been studied. The purpose of this study was to analyze the immunological cross-reactivity of IgE antibodies from children with cow's milk allergy to reindeer and bovine beta-Lg. METHODS: Sera from 17 children and a serum pool of 4 patients with elevated cow's milk-specific IgE were investigated. Beta-Lg from bovine and reindeer milk was isolated in native form and an enzyme-linked immunosorbent inhibition assay was developed. Bovine beta-Lg was used as a capturing antigen and the inhibiting effects of reindeer and bovine beta-Lg on the IgE binding were measured. RESULTS: Cross-reactivity patterns of bovine milk beta-Lg specific IgE to reindeer beta-Lg varied among patients. In general, reindeer beta-Lg showed significantly lower inhibition (mean 43%) of IgE binding to the capturing antigen than did bovine beta-Lg (mean 89%). In some patients, even high concentrations of reindeer beta-Lg only partly eliminated the IgE binding to bovine beta-Lg. CONCLUSIONS: The partial cross-reactivity of human anti-bovine IgE with reindeer beta-Lg suggests that it lacks important bovine epitopes and those that are recognized are only weakly bound.

Microsatellite instability: impact on cancer progression in proximal and distal colorectal cancers.

Whilst individual planning of treatment and follow-up in every colorectal cancer case is an increasing demand, prognostic markers are needed for predicting cancer progression in the primary phase. We studied the effect of replication error (RER)-positivity on colorectal cancer progression by analysing 255 colorectal cancer specimens by polymerase chain reaction (PCR) and fragment analysis and correlating the results with the clinical and histological features of the tumour and with patient outcome. RER-positivity was detected in 12% (28/235) of cases. It was associated with proximal location of the tumour (P < 0.001), poor differentiation (P = 0.001) and large tumour size (P = 0.009). The 5-year cumulative survival rate of the patients with RER-positive cancer of the proximal colon was markedly better (100%) than that of those with RER-negative proximal cancer (74%), whilst in cases of cancer of the distal colon or rectum, RER-positivity (21%) indicated poorer survival than RER-negativity (57%). Thus, it is suggested that RER-positivity has an opposite impact on cancer progression in cases of proximal and distal cancers. RER-positivity appears to indicate improved prognosis only in cases of proximally located cancer, in which it could accordingly be useful as a prognostic marker.

Laminin and type IV collagen in different histological stages of Kaposi's sarcoma and other vascular lesions of blood vessel or lymphatic vessel origin.

Immunohistochemical staining was used to demonstrate basement membrane (BM) laminin and type IV collagen in eight cases of Kaposi's sarcoma (KS). These KS were not associated with AIDS and represented different histological stages of the disease: patch (three cases), plaque (one case), and nodule (four cases). Nine cases of benign angiogenic lesions, five of blood vessel origin, and four of lymphatic vessel origin were also studied. An early event in vascular proliferation at the patch stage of KS was an intersection of dermal collagen bundles and the appearance of granular BM material around this space. With the increase of amount and linear arrangement of BM material, well-defined capillaries were formed. Two types of capillary were found in KS lesions. One showed morphological features of blood capillaries, with a round lumen; thick, continuous BM, and occasional pericytes in the wall. The other included irregularly shaped vessels with thin, often disrupted BMs; thus these capillaries morphologically resembled lymphatic capillaries. BM staining also clearly revealed the vascular nature of the nodular lesions of KS, which were composed of a network of slit-like spaces surrounded by BMs. The solid tumor cell areas were sparse; they were composed of spindle-shaped cells surrounded by thin, interrupted basal laminae. By using antibodies against human laminin and human type IV collagen, it was also possible to demonstrate thin, widely disrupted BMs subendothelially in normal dermal lymphatic capillaries. Typically, the BMs in lymphangiomas and lymphangiectasias were continuous and more clearly defined.

Immunoelectron microscopic localization of laminin, type IV collagen, and type III pN-collagen in reticular fibers of human lymph nodes.

We studied the ultrastructural distribution of laminin, type IV collagen, and the amino terminal pro-peptide of type III collagen (type III pN-collagen) in normal human lymph nodes. After fixation with freshly prepared 4% paraformaldehyde mixed with 0.1% glutaraldehyde, cryoultramicrotomy proved to preserve the antigenicity of these proteins better than embedding in Lowicryl K4M. Sections were treated with rabbit antibodies against the 7S domain of human type IV collagen, the fragment P1 of human laminin, and the amino terminal pro-peptide of human type III pro-collagen, followed by anti-rabbit IgG conjugated to 10-nm colloidal gold. Laminin and type IV collagen were seen in the basement membrane structures of the blood vessels and in the walls of sinuses. The amorphous material between the collagenous fibers in locations corresponding to reticular fibers also contained laminin and type IV collagen. The amino terminal pro-peptide of type III pro-collagen was present in the collagenous fibers in reticular fibers and in the walls of blood vessels and sinuses. Therefore, a significant number of the type III collagen molecules in these fibers must have retained their amino terminal pro-peptide. These results indicate that the basement membrane proteins laminin and type IV collagen are genuine components of reticular fibers, as suggested earlier by immunohistochemical studies at the light microscopic level.

Cell-specific expression of mitochondrial carbonic anhydrase in the human and rat gastrointestinal tract.

Mitochondrial carbonic anhydrase V (CA V) in liver provides HCO3- to pyruvate carboxylase for the first step in gluconeogenesis and HCO3- to carbamyl phosphate synthetase I for the first step in ureagenesis. Because carbamyl phosphate synthetase I and ornithine transcarbamylase are also expressed in enterocytes, we tested the hypothesis that CA V is expressed in the gastrointestinal tract in addition to liver. Polyclonal rabbit antisera were raised against a polypeptide of 17 C-terminal amino acids of human CA V and against purified recombinant mouse isozyme and were used in Western blotting and immunoperoxidase staining of human and rat tissues. Immunohistochemistry showed that CA V is expressed cell-specifically in the alimentary canal mucosa from stomach to rectum. Immunoreactions for CA V were detected in the parietal cells and gastrin-producing G-cells of the stomach and in intestinal enterocytes. Western blotting of human and rat gastrointestinal tissues with isozyme-specific antibodies showed positive signals for CA V with the expected molecular mass. The findings in human tissues paralleled those in rat. The cell-specific pattern of CA V expression suggests a role for CA V in alimentary canal physiology. We propose that mitochondrial CA V participates in the detoxification of ammonia produced in the gastrointestinal tract by providing bicarbonate to carbamyl phosphate synthetase I. (J Histochem Cytochem 47:517-524, 1999)

Expression of the membrane-associated carbonic anhydrase isozyme XII in the human kidney and renal tumors.

Carbonic anhydrase isozyme XII (CA XII) is a novel membrane-associated protein with a potential role in von Hippel-Lindau carcinogenesis. Although Northern blotting has revealed positive signal for CA XII in normal human kidney, this is the first study to demonstrate its cellular and subcellular localization along the human nephron and collecting duct. Immunohistochemistry with a polyclonal antibody (PAb) raised against truncated CA XII revealed distinct staining in the basolateral plasma membrane of the epithelial cells in the thick ascending limb of Henle and distal convoluted tubules, and in the principal cells of the collecting ducts. A weak basolateral signal was also detected in the epithelium of the proximal convoluted tubules. In addition to the normal kidney specimens, this immunohistochemical study included 31 renal tumors. CA XII showed moderate or strong plasma membrane-associated expression in most oncocytomas and clear-cell carcinomas. The segmental, cellular, and subcellular distribution of CA XII along the human nephron and collecting duct suggests that it may be one of the key enzymes involved in normal renal physiology, particularly in the regulation of water homeostasis. High expression of CA XII in some renal carcinomas may contribute to its role in von Hippel-Lindau carcinogenesis.

Immunohistochemistry of carbonic anhydrase isozyme IX (MN/CA IX) in human gut reveals polarized expression in the epithelial cells with the highest proliferative capacity.

MN/CA IX is a recently discovered member of the carbonic anhydrase (CA) gene family that has been identified in the plasma membranes of certain tumor and epithelial cells and found to promote cell proliferation when transfected into NIH3T3 cells. This study presents localization of MN/CA IX in human gut and compares its distribution to those of CA I, II, and IV, which are known to be expressed in the intestinal epithelium. The specificity of the monoclonal antibody for MN/CA IX was confirmed by Western blots and immunostaining of COS-7 cells transfected with MN/CA IX cDNA. Immunohistochemical stainings of human gut revealed prominent polarized staining for MN/CA IX in the basolateral surfaces of the enterocytes of duodenum and jejunum, the reaction being most intense in the crypts. A moderate reaction was also seen in the crypts of ileal mucosa, whereas the staining became generally weaker in the large intestine. The results indicate isozyme-specific regulation of MN/CA IX expression along the cranial-caudal axis of the human gut and place the protein at the sites of rapid cell proliferation. The unique localization of MN/CA IX on the basolateral surfaces of proliferating crypt enterocytes suggests that it might serve as a ligand or a receptor for another protein that regulates intercellular communication or cell proliferation. Furthermore, MN/CA IX has a completely conserved active site domain of CAs suggesting that it could also participate in carbon dioxide/bicarbonate homeostasis.

Clarithromycin-amoxycillin therapy for Helicobacter pylori infection.

BACKGROUND: More convenient therapies are needed to treat Helicobacter pylori infection successfully. Clarithromycin and amoxycillin are effective against H. pylori both in vivo and in vitro. Recent success with a high dose amoxycillin-metronidazole combination therapy led us to evaluate clarithromycin-amoxycillin dual therapy for H. pylori infection. METHODS: We tested the combination of clarithromycin 500 mg t.d.s. with meals plus amoxycillin 750 mg t.d.s. with meals for 10 days for its effect on H. pylori infection in 29 patients with documented H. pylori peptic ulcers. There were 27 men and 2 women, ranging in age from 23 to 77 years. H. pylori and ulcer status were evaluated at entry and at least 4 weeks after ending antimicrobial therapy. For ulcer healing, ranitidine 300 mg was given each evening for 6 weeks. H. pylori status was determined by CLOtest and histology. RESULTS: H. pylori infection was cured in 86% (95% CI = 78-99%). Compliance averaged 93% by pill count. Ten patients (34%) experienced mild side effects: eight reported dysgeusia and two had mild diarrhoea; none discontinued therapy because of side effects. CONCLUSION: We conclude that dual therapy with clarithromycin and amoxycillin is a safe and effective alternative regimen for the successful treatment of H. pylori infections.