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PubMed2002

Cloning and expression pattern of a spermatogenesis-related gene, BEX1, mapped to chromosome Xq22.

Through screening a human fetal brain cDNA library, a cDNA similar to the mouse Bex1 was isolated. This new gene was named brain expressed X-linked protein 1 (BEX1). Northern blot analysis revealed a 1.0 kb transcript highly expressed in brain, pancreas, testis, and ovary, with lower levels present in heart, placenta, liver, kidney, spleen, thymus, prostate, small intestine, colon (no mucus), thyroid, spinal cord, and adrenal gland. No hybridization signal was seen in lung, skeletal muscle, peripheral blood leukocyte, stomach, lymph node, trachea, and bone marrow. The BEX1 gene was localized to chromosome band Xq22 between markers between DXS990 and DXS1059 by screening Stanford radiation hybrid G3 panels. In situ hybridization of mouse testis using BEX1 as a probe detected the signal in the pachytene spermatocytes and spermatids but not in spermatogonia. Furthermore, it was not detected at 6, 9, and 12 days postpartum, was present in low amount on Days 15 and 18 and its expression increased sharply after the initiation of puberty (about 21 days) in mouse testis.

Amino Acid Sequence↗
PubMed2004

Obesity and cancer risk among white and black United States veterans.

BACKGROUND: Obesity has been linked to excess risk for many cancers, but the evidence remains tenuous for some types. Although the prevalence of obesity varies by race, few studies of obesity-related cancer risk have included non-white subjects. METHODS: In a large cohort of male US veterans (3,668,486 whites; 832,214 blacks) hospitalized with a diagnosis of obesity between 1969 and 1996, we examined risk for all major cancer sites and subsites. Person-years accrued from the date of first obesity diagnosis until the occurrence of a first cancer, death, or the end of the observation period (September 30, 1996). We calculated age- and calendar-year adjusted relative risks (RR) and 95% confidence intervals (CI) for cancer among white and black veterans, comparing obese men to men hospitalized for other reasons, with obesity status as time-dependent. For selected cancers, we performed additional analyses stratified by specific medical conditions related to both obesity and risk of those cancers. To determine whether obesity-related cancer risks differed significantly between white and black men, we evaluated heterogeneity of risk for each cancer site. RESULTS: Among white veterans, risk was significantly elevated for several cancers, including cancers of the lower esophagus, gastric cardia, small intestine, colon, rectum, gallbladder and ampulla of vater, male breast, prostate, bladder, thyroid, and connective tissue, and for malignant melanoma, multiple myeloma, chronic lymphocytic leukemia (CLL), and acute myeloid leukemia (AML). Excess risks initially observed for cancers of the liver and pancreas persisted among men without a history of diabetes or alcoholism. Among black veterans, risks were significantly elevated for cancers of the colon, extrahepatic bile ducts, prostate, thyroid, and for malignant melanoma, multiple myeloma, CLL and AML. CONCLUSIONS: Obese men are at increased risk for several major cancers as well as a number of uncommon malignancies, a pattern generally similar for white and black men. Due to the increasing prevalence of obesity and overweight worldwide, it is important to clarify the impact of excess body weight on cancer and to elucidate the mechanisms involved.

Black or African American↗
PubMed1981

Molecular cloning of the K1 capsular polysaccharide genes of E. coli.

Epidemiological and immunological evidence indicates that the K1 capsular polysaccharide confers the property of virulence on Escherichia coli. E coli K1 is associated with invasive diseases in humans and in laboratory and domesticated animals. K1 isolates account for 80% of E. coli neonatal meningitis and comprise the majority of capsular types in neonatal septicaemia without meningitis and in childhood pyelonephritis. Passive administration of K1 antibodies prevented bacteraemia and meningitis in infant rats fed E. coli K1. Nonencapsulated derivatives of these invasive K1 strains did not cause bacteraemia in infant rats, although intestinal colonization was similar to that of the parent strains (M. Achtman and R.P.S., unpublished results). Several reports propose that the E. coli K1 capsular polysaccharide exerts an anti-phagocytic effect similar to that observed with other pathogenic encapsulated bacteria. One approach to studying whether the K1 antigen is sufficient to confer virulence of if other E. coli structures are necessary is to isolate the K1 genes for genetic and biochemical analysis. Recombinant DNA methodology provides a powerful tool for such an approach. Here, we report the molecular cloning of the E. coli K1 antigen genes. The cloned K1 genes synthesize a capsule in E. coli K12 indistinguishable chemically and immunologically from that of wild-type K1 strains.

Cloning, Molecular↗
PubMed1996

Cloning of the mucosal addressin MAdCAM-1 from human brain: identification of novel alternatively spliced transcripts.

The mucosal addressin cell adhesion molecule-1 (MAdCAM-1), expressed selectively on high endothelial venules (HEV) and lamina propria venules, directs lymphocyte traffic by binding the lymphocyte Peyer's patch adhesion molecule-1 (LPAM-1, alpha 4 beta 7). Full-length DNA encoding human MAdCAM-1 was obtained by combining sequences from an expressed sequence tag (EST) identified in an early stage human brain cDNA library, a polymerase chain reaction-derived clone, and a MAdCAM-1 genomic clone. The deduced amino acid sequence revealed an 18 amino acid signal peptide, two N-terminal immunoglobulin (Ig)-like domains conserved (59-65%) in sequence with those of the mouse homologue, an 86 amino acid mucin-like region rich in serine-threonine residues, a 20 amino acid transmembrane domain and a 43 amino acid charged cytoplasmic domain. No counterpart to the third IgA-like domain of mouse MAdCAM-1 was present; however, the serine-threonine-rich mucin domain was extended as two distinguishable major and minor mucin regions unrelated to the mouse domain. The major domain is formed from six tandem repeats of an eight amino acid sequence having the MUC-2-related consensus DTTSPEP/SP. Human MAdCAM-1 mRNA transcripts were restricted to small intestine, colon, spleen, pancreas and brain. Alternatively spliced MAdCAM-1 variants were identified that lack parts of the second Ig domain and all or part of the major mucin domain, indicating that the function of this vascular addressin is regulated by extensive modifications to its multi-domain structure.

Alternative Splicing↗
PubMed2005

Second primary cancers among 109 000 cases of non-Hodgkin's lymphoma.

An analysis of other primary cancers in individuals with non-Hodgkin's lymphoma (NHL) can help to elucidate this cancer aetiology. In all, 109 451 first primary NHL were included in a pooled analysis of 13 cancer registries. The observed numbers of second cancers were compared to the expected numbers derived from the age-, sex-, calendar period- and registry-specific incidence rates. We also calculated the standardised incidence ratios for NHL as a second primary after other cancers. There was a 47% (95% confidence interval 43-51%) overall increase in the risk of a primary cancer after NHL. A strongly significant (P<0.001) increase was observed for cancers of the lip, tongue, oropharynx*, stomach, small intestine, colon*, liver, nasal cavity*, lung, soft tissues*, skin melanoma*, nonmelanoma skin*, bladder*, kidney*, thyroid*, Hodgkin's lymphoma*, lymphoid leukaemia* and myeloid leukaemia. Non-Hodgkin's lymphoma as a second primary was increased after cancers marked with an asterisk. Patterns of risk indicate a treatment effect for lung, bladder, stomach, Hodgkin's lymphoma and myeloid leukaemia. Common risk factors may be involved for cancers of the lung, bladder, nasal cavity and for soft tissues, such as pesticides. Bidirectional effects for several cancer sites of potential viral origin argue strongly for a role for immune suppression in NHL.

Aged↗
PubMed2004

GBPI, a novel gastrointestinal- and brain-specific PP1-inhibitory protein, is activated by PKC and inactivated by PKA.

The activities of PP1 (protein phosphatase 1), a principal cellular phosphatase that reverses serine/threonine protein phosphorylation, can be altered by inhibitors whose activities are themselves regulated by phosphorylation. We now describe a novel PKC (protein kinase C)-dependent PP1 inhibitor, namely GBPI (gut and brain phosphatase inhibitor). The shorter mRNA that encodes this protein, GBPI-1, is expressed in brain, stomach, small intestine, colon and kidney, whereas a longer GBPI-2 splice variant mRNA is found in testis. Human GBPI-1 mRNA encodes a 145-amino-acid, 16.5 kDa protein with pI 7.92. GBPI contains a consensus PP1-binding motif at residues 21-25 and consensus sites for phosphorylation by enzymes, including PKC, PKA (protein kinase A or cAMP-dependent protein kinase) and casein kinase II. Recombinant GBPI-1-fusion protein inhibits PP1 activity with IC50=3 nM after phosphorylation by PKC. Phospho-GBPI can even enhance PP2A activity by >50% at submicromolar concentrations. Non-phosphorylated GBPI-1 is inactive in both assays. Each of the mutations in amino acids located in potential PP1-binding sequences, K21E+K22E and W25A, decrease the ability of GBPI-1 to inhibit PP1. Mutations in the potential PKC phosphoacceptor site T58E also dramatically decrease the ability of GBPI-1 to inhibit PP1. Interestingly, when PKC-phosphorylated GBPI-1 is further phosphorylated by PKA, it no longer inhibits PP1. Thus, GBPI-1 is well positioned to integrate PKC and PKA modulation of PP1 to regulate differentially protein phosphorylation patterns in brain and gut. GBPI, its closest family member CPI (PKC-potentiated PP1 inhibitor) and two other family members, kinase-enhanced phosphatase inhibitor and phosphatase holoenzyme inhibitor, probably modulate integrated control of protein phosphorylation states in these and other tissues.

Amino Acid Sequence↗
PubMed2003

A novel serine protease predominately expressed in macrophages.

We have identified a novel serine protease designated EOS by sequence identity searches. The deduced protein contains 284 amino acids with an active form containing 248 amino acids starting from an Ile-Val-Gly-Gly motif. The active form comprises a catalytic triad of conserved amino acids: His77, Asp126 and Ser231. It shares 44% identity with beta-tryptase and belongs to the S1 trypsin-like serine-protease family. Interestingly, this gene also maps to human chromosome 16p13.3. The purified protease showed amidolytic activity, cleaving its substrates before arginine residues. Tissue distribution by immunohistochemistry analysis demonstrated that EOS is highly expressed in spleen and moderately expressed in intestine, colon, lung and brain. We confirmed this expression pattern at the mRNA level by performing in situ hybridization. The results from both immunohistochemistry and in situ hybridization indicate that EOS is associated with macrophages. We corroborated this observation by double immunofluorescence using the anti-EOS antibody and an anti-CD68 antibody, a macrophage specific marker. Furthermore, we have detected a dramatic increase in immune staining of EOS in cultured U937 cells treated with PMA, which represent activated macrophages. This up-regulation is also reflected by elevated EOS mRNA in the PMA-treated U937 cells detected by Northern blotting. Since macrophages have important roles in various pathological conditions, such as wound healing, atherosclerosis and numerous inflammatory diseases, the localization of this novel serine protease to active macrophages may help to further the elucidation of the roles of this gene product in modulating these disorders.

Amino Acid Sequence↗
PubMed1997

Molecular cloning, chromosomal assignment and tissue-specific expression of a murine alpha(1,2)fucosyltransferase expressed in thymic and epididymal epithelial cells.

Terminal Fucalpha(1-2)Galbeta epitopes have been proposed to play significant roles in cell-cell interactions in development, cell adhesion, and malignant transformation. To begin to investigate the regulation and function of alpha(1-2)fucosylated epitopes in an animal model, we have isolated and characterized a mouse genomic DNA segment encoding a protein orthologous to the human H blood group locus alpha(1,2)fucosyltransferase (FUT1). This segment maintains an open reading frame encoding 376 amino acids sharing 75% sequence identity with the enzyme encoded by human FUT1, and 55% sequence identity with the enzyme encoded by the human Secretor blood group locus (FUT2). Expression of the open reading frame in COS-7 cells yields an alpha(1,2)fucosyltransferase activity with a Km of 7.6 mM for phenyl-beta-d-galactoside. Southern blotting and interspecific backcross analyses indicate that this murine locus represents a single copy sequence mapping to a novel locus 2.1 centimorgans from the Klk1 locus, in a region of homology between mouse chromosome 7 and the human FUT1 locus on the long arm of chromosome 19. Mouse FUT1 yields a 2.8 kb mRNA transcript identifiable in many organs, including thymus, lung, stomach, pancreas, small intestine, colon, uterus and epidiymis. Hybridization analyses in situ localize expression of FUT1 transcripts to thymic medullary and epididymal epithelial cells, implying that this gene determines the expression of cell surface Fucalpha(1-2)Galbeta epitopes in these tissues.

Amino Acid Sequence↗
PubMed2001

Cerebral and regional organ perfusion in pigs during xenon anaesthesia.

Little is known about the haemodynamic effects of inhaled xenon on regional organ perfusion. The aim of this study was to investigate the effect of 79% xenon ventilation on organ perfusion in pigs. We investigated 10 pigs, which were randomly allocated to receive either xenon 79% or total intravenous anaesthesia (TIVA)/oxygen anaesthesia. Microspheres were used to determine organ perfusion. The following regions of interest were investigated: cerebral cortex, medulla oblongata, brainstem, cerebellum, liver, kidney, small intestine, colon, muscle, skin and heart. The results demonstrated a significant increase in regional perfusion in the brainstem (+63%), cerebral cortex (+38%), medulla oblongata (+35%) and cerebellum (+34%). All other organs showed no significant change in regional perfusion. We conclude that xenon should be used with caution in clinical situations associated with pathological increases in intracranial pressure, e.g. neurosurgical procedures, head injury, cerebral mass lesions or stroke.

Anesthetics, Combined↗
PubMed2003

Caesarean section increases the risk of hospital care in childhood for asthma and gastroenteritis.

OBJECTIVE: To investigate if caesarean section (CS) increases the risk for childhood asthma and gastroenteritis with reference made to children born with vaginal delivery (VD). METHODS: Retrospective study of data from linked Swedish medical service registers--Medical Birth Registry (MBR) and Hospital Discharge Registry (HDR). Data were obtained from women without any background/perinatal morbidity noted, and from children without any neonatal complications. Children that had reached at least 1 year of age and were found in the HDR were considered as cases, whereas children not found in the HDR or hospitalized for other causes than asthma or gastroenteritis were defined as controls. Odds ratios (OR) stratified for year of birth, maternal age, parity and smoking in early pregnancy were calculated. Investigations were made comparing the risk for in hospital treatment for asthma or gastroenteritis in CS children and in VD siblings of CS children. The overall inpatient morbidity in CS and VD children were also investigated. RESULTS: The OR for asthma in CS children was 1.31 [95% confidence interval (CI) 1.23-1.40]. The same OR, 1.31, was found for gastroenteritis (95% CI 1.24-1.38). The OR for CS children having experienced both asthma and gastroenteritis was further increased (1.74, 95% CI 1.36-2.23). The risk for asthma in VD siblings of CS children was not significantly increased, whereas VD siblings experienced a slightly increased risk for gastroenteritis. CS children had an increased overall in hospital morbidity when compared to VD children. CONCLUSION: There is a significant increase of the risk for developing symptoms of asthma and/or gastroenteritis that motivates admission for hospital care in CS children older than 1 year. It is speculated that a disturbed intestinal colonization pattern in CS children may be a common pathogenic factor.

Adult↗
PubMed1999

The Tir-binding region of enterohaemorrhagic Escherichia coli intimin is sufficient to trigger actin condensation after bacterial-induced host cell signalling.

Enterohaemorrhagic Escherichia coli (EHEC) has emerged as an important agent of diarrhoeal disease. Attachment to host cells, an essential step during intestinal colonization by EHEC, is associated with the formation of a highly organized cytoskeletal structure containing filamentous actin, termed an attaching and effacing (A/E) lesion, directly beneath bound bacteria. The outer membrane protein intimin is required for the formation of this structure, as is Tir, a bacterial protein that is translocated into the host cell and is thought to function as a receptor for intimin. To understand intimin function better, we fused EHEC intimin to a homologous protein, Yersinia pseudotuberculosis invasin, or to maltose-binding protein. The N-terminal 539 amino acids of intimin were sufficient to promote outer membrane localization of the C-terminus of invasin and, conversely, the N-terminal 489 amino acids of invasin were sufficient to promote the localization of the C-terminus of intimin. The C-terminal 181 residues of intimin were sufficient to bind mammalian cells that had been preinfected with an enteropathogenic E. coli strain that expresses Tir but not intimin. Binding of intimin derivatives to preinfected cells correlated with binding to recombinant Tir protein. Finally, the 181-residue minimal Tir-binding region of intimin, when purified and immobilized on latex beads, was sufficient to trigger A/E lesions on preinfected mammalian cells.

Actins↗
PubMed2000

Identification of a novel genetic locus that is required for in vitro adhesion of a clinical isolate of enterohaemorrhagic Escherichia coli to epithelial cells.

Enterohaemorrhagic Escherichia coli (EHEC) are food-borne intestinal pathogens with a low infectious dose. Adhesion of some EHEC strains to epithelial cells is attributed, in part, to intimin, but other factors may be required for the intestinal colonizing ability of these bacteria. In order to identify additional adherence factors of EHEC, we generated transposon mutants of a clinical EHEC isolate of serotype O111:H-, which displayed high levels of adherence to cultured Chinese hamster ovary (CHO) cells. One mutant was markedly deficient in CHO cell adherence, human red blood cell agglutination and autoaggregation. Sequence analysis of the gene disrupted in this mutant revealed a 9669 bp novel chromosomal open reading frame (ORF), which was designated efa1, for EHEC factor for adherence. efa1 displayed 28% amino acid identity with the predicted product of a recently described ORF from the haemolysin-encoding plasmid of EHEC O157:H7. The amino termini of the putative products of these two genes exhibit up to 38% amino acid similarity to Clostridium difficile toxins A and B. efa1 occurred within a novel genetic locus, at least 15 kb in length, which featured a low G+C content, several insertion sequence homologues and a homologue of the Shigella flexneri enterotoxin ShET2. DNA probes prepared from different regions of efa1 hybridized with all of 116 strains of attaching-effacing E. coli (AEEC) of a variety of serotypes, including enteropathogenic E. coli (EPEC) and EHEC, but with none of 91 non-AEEC strains. Nevertheless, efa1 was not required for the attachment-effacement phenotype, and the efa1 locus was not physically linked to the locus for enterocyte effacement (LEE) pathogenicity island, which is responsible for this phenotype in EPEC. These findings suggest that efa1 encodes a novel virulence-associated determinant of AEEC, which contributes to the adhesive capacity of these bacteria.

Amino Acid Sequence↗
PubMed2003

Phase variation of the 987P-like CS18 fimbriae of human enterotoxigenic Escherichia coli is regulated by site-specific recombinases.

The gene cluster of the CS18 (PCFO20) fimbriae of human enterotoxigenic Escherichia coli (ETEC) was found to include seven genes (fotA to fotG) that are similar to each of the seven structural and export proteins of the 987P fimbriae. However, no analogous gene to the fasH regulatory gene, which is located at the 3' end of the 987P gene cluster and encodes an AraC-like activator of transcription, could be detected. Surprisingly, two novel genes (fotS and fotT) encoding proteins similar to the site-specific recombinases of the type 1 fimbriae (FimB and FimE) were identified at the 5' end of the fot gene cluster. These genes were shown to be required for the catalysis of a 312 bp-inversion just upstream of fotA. The inversion determines CS18 fimbrial phase variation. FotS participates in inverting the 312 bp-segment in both the ON and OFF orientation, whereas FotT has a bias for the OFF oriented recombination. Similar regulators of fimbriation by phase variation were described in uropathogenic and commensal Enterobacteriaceae. In contrast, only AraC-like transcriptional activators were previously described as regulators of the intestinal colonization factors of human ETEC isolates. Thus, the CS18 and 987P gene clusters encode similar components for fimbrial biogenesis but different types of regulators for fimbriation. The combination of blocks of genes encoding similar structural products but different regulatory proteins underlines how modular DNA rearrangements can evolve by serving pathogen diversification. Acquisition of a phase variation module to regulate fimbrial genes is proposed to be beneficial for the adaptation and transmission of pathogens.

Amino Acid Sequence↗
PubMed2002

Isolation and characterization of MUC15, a novel cell membrane-associated mucin.

The present work reports isolation and characterization of a highly glycosylated protein from bovine milk fat globule membranes, known as PAS III. Partial amino-acid sequencing of the purified protein allowed construction of degenerate oligonucleotide primers, enabling isolation of a full-length cDNA encoding a protein of 330 amino-acid residues. N-terminal amino-acid sequencing of derived peptides and the purified protein confirmed 76% of the sequence and demonstrated presence of a cleavable signal peptide of 23 residues, leaving a mature protein of 307 amino acids. Database searches showed no homology to any other proteins. A survey of the human genome indicated the presence of a corresponding gene on chromosome band 11p14.3. Isolation and sequencing of the complete cDNA sequence of the human homologue proved the existence of the gene product (334 amino-acid residues). This novel mucin-like protein was named MUC15 by appointment of the HUGO Gene Nomenclature Committee. The deduced amino-acid sequences of human and bovine MUC15 demonstrated structural hallmarks characteristic for other membrane-bound mucins, such as a serine, threonine, and proline-rich extracellular region with several potential glycosylation sites, a putative transmembrane domain, and a short cytoplasmic C-terminal. We have shown the presence of O-glycosylations, identified N-glycosylations at 11 of 15 potential sites in bovine MUC15, and a splice variant encoding a short secreted mucin. Finally, analysis of human and bovine cDNA panels and libraries showed MUC15 gene expression in adult human spleen, thymus, prostate, testis, ovary, small intestine, colon, peripheral blood leukocyte, bone marrow, lymph node, tonsil, breast, fetal liver, bovine lymph nodes and lungs of both species.

Alternative Splicing↗
PubMed1999

Expression of MUC2, MUC5AC and MUC6 apomucins in carcinoma, dysplasia and non-dysplastic epithelia of the gallbladder.

To date, nine apomucins have been characterized and their expression in malignant and premalignant lesions is under evaluation. The purpose of this study was to characterize immunohistochemically the expression of MUC2 (colonic/ intestinal type), MUC5AC (gastric surface type), and MUC6 (pyloric gland type) apomucins in 55 patients with gallbladder carcinoma (10 with in situ carcinoma, 45 with invasive carcinoma), 20 patients with gallbladder dysplasia, and 15 patients with non-dysplastic gallbladder. MUC2 was expressed mainly in 'goblet type' cells. The frequency was increased in non-dysplastic gallbladder (47%), dysplasia (75%), and in situ carcinoma (100%), and decreased in invasive carcinoma (58%). Carcinoma cells expressing MUC2, which were usually distributed at superficial areas, and well-differentiated carcinoma expressed MUC2 more extensively than moderately and poorly differentiated ones. MUC5AC was frequently expressed in gallbladder irrespective of non-dysplastic epithelia, dysplasia and carcinoma. MUC5AC was expressed also in carcinoma cells at deeply invasive sites. MUC6 was expressed frequently in pseudopyloric gland metaplasia as well as dysplasia and carcinoma. In conclusion, non-dysplastic gallbladder has a similar phenotype to gastric pyloric mucosa. Gallbladder carcinoma exhibits both intestinal and gastric surface phenotypes in the early stage of carcinogenesis, with the gastric surface phenotype dominant in invasive carcinoma.

Adult↗
PubMed1999

Morphology of the lymphoid organs of the bottlenose dolphin, Tursiops truncatus.

The anatomy of the lymphoid organs was studied during the course of detailed dissections of 50 beach-stranded bottlenose dolphins, Tursiops truncatus. Constant lymph nodes occur in 4 groups, based on their location and structure. These groups are somatic, including nodes of the cervical region and pelvic recess; lung-associated, included marginal, diaphragmatic and hilar nodes; visceral, including the mesenteric, pancreatic, pericolic and porta hepatis nodes; and aortic arch nodes. Lymphatic drainage of the lung is primarily to the marginal and diaphragmatic nodes. The mesenteric node mass is well-endowed with capsular and trabecular smooth muscle, and a network of muscle fascicles within the organ implies an important contractile function in the circulation of lymph. In addition to constant nodes, occasionally nodes are found in relation to the thoracic aorta, the kidney, and under the scapula. Gut-associated structures include dorsal and ventral oropharyngeal tonsils, mucosal aggregates in the straight segment of the intestine (colon) and anal tonsils; this gut-associated lymphoid tissue tends to involute with age, being greatly reduced by puberty. Formed lymphoid organs include the thymus and the spleen, the latter being relatively small in relation to body size. None of these structures is unique among cetaceans, but the anal tonsils are particularly well developed in T. truncatus. The lymphoid aggregates in the colon resemble the arrangement in the vermiform appendix, which is lacking in most cetaceans, and may have functions analogous to that organ.

Animals↗
PubMed2003

Binding of extracellular matrix molecules by probiotic bacteria.

AIMS: The aim of this study was to investigate extracellular matrix (ECM) and mucin binding of selected bacterial isolates with probiotic features in comparison with commercially used probiotic bacteria. METHODS AND RESULTS: ECM molecules were immobilized in microtitre plates (mucin and fetuin) or on the surface of latex beads. Porcine mucin was bound by all 13 probiotic strains tested with important inter-strain differences; however, fetuin binding was similar (weak) for all 14 strains tested. Strongly positive (three) binding of bovine fibrinogen was expressed by strains from fermented food (Lactobacillus rhamnosus GG, L. casei Shirota and L. johnsonii La1) as well as by L. casei L.c., Lactobacillus sp. 2I3 and by L. plantarum LP. The other strains expressed moderate (2) or weakly positive (1) binding of bovine fibrinogen. Strongly positive (3) binding of porcine fibronectin was observed only with two strains; however, all other strains also bound this molecule. Bovine lactoferrin was bound to a higher extent than transferrins. SIGNIFICANCE AND IMPACT OF THE STUDY: Some animal strains (at least L. casei L.c. and Lactobacillus sp. 2I3) are comparable with the commercially used strains with respect to their ECM binding ability. As this feature is important for probiotic bacteria to be able to colonize intestine, these strains should be considered for their wider use in fermented feed (or probiotic preparations) for animals.

Animals↗
PubMed2001

Cytokeratin 7 and 20 and thyroid transcription factor 1 can help distinguish pulmonary from gastrointestinal carcinoid and pancreatic endocrine tumors.

Expression of cytokeratin (CK) 7 and 20 is commonly used to help distinguish adenocarcinomas from different sites. Thyroid transcription factor 1 (TTF-1) is a 38-kd protein, located primarily in the nucleus of type 2 pneumocytes and clara cells. TTF-1 has been shown to be present in a variety of lung and thyroid tumors and in pulmonary small-cell carcinomas. Carcinoid tumors from the lung and the gastrointestinal (GI) tract are histologically similar and thus are difficult to differentiate from each other based on histologic criteria. Pancreatic endocrine tumors (PET) have a similar histologic appearance to these other tumors. The purpose of this study was to determine the efficacy of differentiating these 3 groups of tumors by their expression of CK7, CK20, and TTF-1. Routinely processed paraffin-embedded tissue sections from 62 carcinoid tumors (lung, 16; gastrointestinal [GI] tract, 46) and 12 PETs were immunohistochemically stained for CK7, CK20, and TTF-1. The degree of expression in each tumor was graded as 1+ (1% to 10% of cells positive), 2+ (11% to 25%), 3+ (26% to 50%), and 4+ (>50%). The data were compared between tumor types and between carcinoid tumors from the various locations in the GI tract (stomach, 8; small intestine, 19; large intestine, 17; appendix, 2). CK7 was expressed in 10 (63%) of 16 pulmonary carcinoid tumors and only 5 (11%) of 46 GI carcinoid tumors (P <.001). Pancreatic endocrine tumors showed CK7 positivity in 6 (50%) of 12 cases, which was similar to the findings in lung carcinoids and significantly higher than in GI carcinoids (P <.01). CK20 was expressed in 0 (0%) of 16 pulmonary carcinoid tumors, in contrast to 24% and 33% of GI carcinoid tumors (P <.05) and PETs (P <.05), respectively. TTF-1 expression was highly specific for pulmonary carcinoid tumors. This peptide was present in 11 (69%) of 16 pulmonary carcinoid tumors and in only 1 (2%) of 46 and 0 (0%) of 12 GI carcinoid tumors (P <.001) and PETs (P <.001), respectively. A CK7(+)/CK20(-)/TTF-1(+) immunopanel result was moderately sensitive (sensitivity, 50%), and highly specific (specificity, 100%), for a diagnosis of pulmonary carcinoid tumor. CK7, CK20, and TTF-1 did not differ significantly between carcinoid tumors located in different sites of the GI tract. However, a trend was observed toward a lower prevalence of CK20 positivity in gastric tumors (P =.06) than in GI carcinoid tumors from the small intestine, colon, or appendix. Expression of CK7 and CK20, and particularly TTF-1, may be useful in distinguishing pulmonary from GI carcinoid tumors and PETs, especially when evaluated as a panel of markers. TTF-1 is highly specific for pulmonary carcinoid tumors.

Adult↗