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Immunoglobulin concentrations in duodenal fluid of infants and children.

The immunoglobulin content of duodenal fluid in children at different ages has not as yet been determined, while that of serum, feces, and saliva has been well established. In 92 normal infants, children, and young adults on whom duodenal intubation was performed, duodenal fluid IgA, IgM, and IgG levels were measured. From these data, a developmental profile of immunoglobulins in duodenal fluid from 2 weeks of life to 19 years was obtained. Duodenal fluid IgA, IgM, and IgG appeared to maintain rather constant levels. The grand mean IgA level was lower than the mean IgG level (12.7 +/- 0.8 vs 29.1 +/- 2.5 mg/g of protein). Secretory component was detected in all duodenal fluids. IgG concentrations were greater than those of IgM (29.1 +/- 2.5 vs 13.2 +/- 1.4 mg/g of protein) over all age ranges. The developmental patterns of all immunoglobulins appeared to be different from those observed in serum or saliva with the exception of duodenal fluid IgA, which has a pattern similar to that of salivary IgA.

Adolescent↗

The nucleotide sequence of a 39 kb segment of yeast chromosome IV: 12 new open reading frames, nine known genes and one genes for Gly-tRNA.

The complete nucleotide sequence of a 39,090 bp segment from the left arm of yeast chromosome IV was determined. Twenty-one open reading frames (ORFs) longer than 100 amino acids and a Gly-tRNA gene were discovered. Nine of the 21 ORFs (D0892, D1022, D1037, D1045, D1057, D1204, D1209, D1214, D1219) correspond to the previously sequenced Saccharomyces cerevisiae genes for the NAD-dependent glutamate dehydrogenase (GDH), the secretory component (SHR3), the GABA transport protein (UGA4), the high mobility group-like protein (NHP2), the hydroxymethylbilane synthase (HEM3), the methylated DNA protein-cysteine S-methyltransferase (MGT1), a putative sugar transport protein, the Shm1 protein (SHM1) and the anti-silencing protein (ASF2). The inferred amino acid sequences of 11 ORFs show significant similarity with known proteins from various organisms, whereas the remaining ORF does not share any similarity with known proteins.

Chromosome Mapping↗

Immunohistochemical localization of the epidermal growth factor, transforming growth factor alpha, and their receptor in the human mesonephros and metanephros.

The distribution of epidermal growth factor (EGF), transforming growth factor alpha (TGF alpha), and EGF/TGF alpha receptor were studied by means of immunohistochemical methods starting from the very early stages of human embryonic kidney development. Mesonephros and metanephros were examined in order to detect immunoreactive staining in serial sectioned embryos and fetal kidneys. Anti-EGF immunoprecipitates were found in the S-shaped mesonephric vesicles of 6-week old embryos as well as in the mesonephric duct albeit with a lower degree of reactivity. Intense reactivity was observed in the metanephros within the blastemic caps of the same gestational period; the reaction was weaker within the ureteric bud branches. Bowman's capsule, proximal tubules, and collecting ducts were also reactive in the fetal kidney to varying degrees. The distribution of TGF alpha reactivity in the mesonephros was similar to that observed for EGF but with a lower intensity. In contrast, there was no reactivity in the metanephros, at least during the embyronic periods examined. By the 11th week of gestation, an intense reactivity for TGF alpha polipeptide was shown in the fetal kidney at the level of the proximal tubules and Bowman's capsule; distal tubules as well as all urinary structures from the collecting ducts to the pelvis were less reactive. Finally, EGF/TGF alpha receptor reactivity was identified by the 6th week of development, being more intense in the mesonephros at the level of the mesonephric duct cells. In the metanephros, the ureteric bud-derived branches were reactive, whereas most of the blastemic tissue did not stain. By the 11th week, only the collecting ducts and the remaining urinary structures contained reaction products: Reactivity was distributed to the tissues originating from the ureteric bud branching. Taking into account recent advances in knowledge about the biology of growth factors, the hypothesis is proposed that the secretory components (vesicles, glomerulus, and tubules) of renal anlagen might release the growth factors while the cells of the urinary tract (i.e., collecting duct, pelvis, etc.) may be their targets.

Epidermal Growth Factor↗

Effects of inhaled beclomethasone compared to systemic dexamethasone on lung inflammation in preterm infants at risk of chronic lung disease.

The purpose of this study was to compare the effects of daily inhaled beclomethasone (3 x 500 microg) started on day 3 of life, with that of systemic dexamethasone (0.5 mg/kg/day) started between days 11-13 on clinical variables, lung inflammation, and pulmonary microvascular permeability in preterm infants at risk for chronic lung disease (CLD). Following administration of surfactant, preterm neonates with RDS and a birth weight of less than 1,200 g were included in this comparative observational pilot study when still mechanically ventilated and with an oxygen requirement on the third day of life. The patients (gestational age 26.1+/-0.9 weeks, birth weight 826+/-140 g, mean+/-SD) were alternately allocated to prophylactic treatment with inhaled beclomethasone (n = 7), or to early systemic dexamethasone therapy after day 10 of life, if clinically indicated (n = 9). Pulmonary inflammation and lung permeability were assessed by analyzing the levels of interleukin-8, elastase alpha1 proteinase inhibitor, free elastase activity, and albumin in tracheal aspirates on days 10 and 14 of life. The secretory component of IgA served as reference protein. We observed no significant differences in the concentrations of interleukin-8, elastase alpha1 proteinase inhibitor, and albumin between the two groups on day 10 of life. On day 14, 3 (median; range, 1-3) days following initiation of dexamethasone treatment, concentrations of the inflammatory mediators and of albumin were significantly lower in the group on systemic steroid therapy than in the group treated with inhaled steroids (P < 0.01). Additionally, there was a significant difference in oxygen requirements between both groups on day 14. In the group treated with inhaled steroids, concentrations of the inflammatory mediators, albumin, and oxygen requirements did not show a difference between day 10 and 14. We conclude that, in contrast to systemic dexamethasone treatment, a 12-day course of inhaled beclomethasone does not affect lung inflammation and pulmonary microvascular permeability in preterm infants at risk for CLD within the first 2 weeks of life.

Administration, Inhalation↗

Preservation of cytometric DNA distribution and epithelial marker expression after tumor progression of human large bowel carcinomas.

Tumor specimens were obtained from seven patients with large bowel carcinomas at operation of the primary neoplasm and by resection of local recurrences or metastases 2 1/2 to 36 months later. All specimens were evaluated with regard to nuclear DNA distribution as measured by flow cytometry and expression of carcinoembryonic antigen (CEA), secretory component, epithelial IgA, and HLA-DR antigens, as determined by immunofluorescence staining of tissue sections. Both the DNA distributions and the immunohistochemical staining patterns were similar in the primary and secondary tumors. These findings are in keeping with a monoclonal or oligoclonal tumor progression in advanced large bowel carcinoma.

Adult↗

Tumor-associated antigens in breast carcinomas. Prognostic significance.

In an attempt to identify biologic markers that might predict prognosis in breast cancer patients, the presence or absence of seven tumor-associated antigens in 54 infiltrating breast carcinomas was correlated with tumor recurrence rates (minimum five-year follow-up), axillary lymph node metastases and tumor volume. Immunohistochemical kappa-casein was present in 30 (56%) tumors, alpha-lactalbumin in 39 (72%) tumors, secretory component of IgA in 26 (48%) tumors, carcinoembryonic antigen in 34 (63%) tumors, pregnancy-specific beta-1-glycoprotein in 7 (13%) tumors, beta subunit of human chorionic gonadotrophin in 1 (2%) tumor and human placental lactogen in 0 (0%) tumors. There was no significant correlation between the presence or absence in tumor of any of the antigens, and prognosis as assessed either by 5-year recurrence rates (P greater than 0.18) or by the presence of axillary lymph node metastases (P greater than 0.20). No significant difference was noted in mean tumor volume (cm3) +/- SEM, between tumors with or without antigen immunoreactivity (P greater than 0.05).

Antigens, Neoplasm↗

Immunohistochemical localization of CA 19-9 and CEA in pancreatic carcinoma and associated diseases.

The distribution of carbohydrate antigen 19-9 (CA 19-9), on pancreatic carcinomas and associated diseases correlated with carcinoembryonic antigen (CEA) localization is described. Immunohistochemical examinations were made on pancreatic specimens from 45 patients with pancreatic carcinoma. In normal pancreatic duct, the antigens were restricted to the luminal surface. In some hyperplastic epithelium, however, they were localized not only to the basolateral plasma membranes but also to the cytoplasm. In neoplastic glands, the antigens were distributed over the entire surface of the cells and in the surrounding stroma adjacent to the basal membranes of the malignant cells. The findings were compatible with previous observations of CEA and secretory component (SC) localization in gastric and colonic mucosa. In addition, the staining intensity of CA 19-9 in the routine formalin-fixed and paraffin-embedded sections was much superior to that of CEA. The relationship between CA 19-9 and other blood group antigens, such as Lewis a and Lewis b, also was discussed. Localizations of these antigens in pancreatic tissues are useful for the biologic analysis of abnormalities of the pancreatic duct epithelium, and may well facilitate pathologic diagnosis of pancreatic carcinoma.

Antigens, Neoplasm↗

A multivariate analysis of pathologic prognostic indicators in large bowel cancer.

A multivariate analysis of the pathologic data of 350 patients with primary colorectal cancer was performed. In addition to conventional parameters such as shape and size of the primary tumor, central node involvement, angioinvasive growth, grade, and stage, new variables such as the immunoreactivity patterns of carcinoembryonic antigen (CEA), CA 19-9, mucin, serotonin, secretory component (SC), and the DNA index were tested for their potential prognostic value. Every variable except CA 19-9, serotonin, and DNA showed significant prognostic information in univariate analysis. However, in the multivariate analysis stage was the predictive factor with the highest hazard ratio, but absence of central node involvement, tumors with diameters between 3.5 cm and 6 cm, exophytic tumor growth, well-differentiated tumors, tumors with CEA immunoreactivity, absence for staining with serotonin, and diploid tumors also were included in the relative risk model. Thus, the aforementioned variables appear to play a role in the establishment of a prognostic index.

Aged↗

Cell lineage markers in human pancreatic cancer.

The normal pancreas consists of three major cell types or lineages that share a common embryologic origin from pluripotent endodermal precursors. The type of cell that undergoes neoplastic transformation to form a pancreatic carcinoma is controversial and may influence the phenotype and biologic behavior of the tumor. In this study, immunohistologic techniques were used to determine the cell lineage differentiation expressed in 29 primary exocrine pancreatic adenocarcinomas, five metastatic exocrine pancreatic adenocarcinomas, and five islet cell neoplasma. Specimens of normal pancreas and chronic pancreatitis were used for comparison. The cell lineage markers consisted of monoclonal and polyclonal antibodies against trypsin and lipase (acinar cells); secretory component, carbonic anhydrase II, and pancreatic cancer mucin SPan-1 (ductal cells); and chromogranin-A and somatostatin (islet cells). The expression of carcinoembryonic antigen (CEA) and lysozyme were also determined. This collection of markers allowed the differentiation between acinar, ductal, and islet cells of normal pancreas and chronic pancreatitis specimens. The expression of cell lineage markers in islet cell tumors was homogeneous and restricted to chromogranin-A. In contrast, the expression of these markers in primary and metastatic exocrine pancreatic adenocarcinomas was variable. Reactivity with monoclonal anti-CEA was absent in normal pancreas, and was present in 83% of chronic pancreatitis specimens as well as 90% of exocrine pancreatic adenocarcinomas. In addition, lysozyme reactivity was absent in normal pancreas; however, lysozyme was expressed in one case of chronic pancreatitis, 17 cases of primary carcinoma, and three cases of metastatic carcinoma. These findings support the concept that the original transformed cell type in many pancreatic exocrine carcinomas resemble endodermal "stem cells" that retain the capability of differentiation along more than one cell lineage pathway.

Biomarkers↗

Effects of early inhaled beclomethasone therapy on tracheal aspirate inflammatory mediators IL-8 and IL-1ra in ventilated preterm infants at risk for bronchopulmonary dysplasia.

We tested the hypothesis that inhaled beclomethasone therapy for prevention of bronchopulmonary dysplasia (BPD) reduces pulmonary inflammation. As part of a randomized, placebo-controlled trial, interleukin-8 (IL-8) and interleukin-1 receptor antagonist (IL-1ra) concentrations in tracheal aspirates were measured as markers of pulmonary inflammation. On study days 1 (baseline), 8, 15, and day 28 of age, samples were obtained from enrolled infants (birth weights <1,251 g, gestational age <33 week, 3 to 14 days of age) who remained ventilated and had not received systemic glucocorticoid therapy. Cytokine levels (pg/microg of free secretory component of immunoglobulin A) were compared between groups. We determined whether baseline cytokine levels modified treatment effect regarding subsequent need for systemic glucocorticoid therapy or occurrence of BPD (age 28 days). Tracheal aspirates were obtained from 161 infants (77 receiving beclomethasone, 84 receiving placebo). Median IL-8 levels were lower in beclomethasone versus placebo infants on study days 8 (82.9 vs. 209.2, P < 0.01) and 15 (37.4 vs. 77.4, P < 0.03) after controlling for antenatal glucocorticoid therapy and maternal race. Median IL-1ra levels were lower in beclomethasone versus placebo infants only on study day 8 (86.5 vs. 153.3, P < 0.01). Fewer beclomethasone infants with baseline IL-8 levels in the interquartile range required systemic glucocorticoid therapy (beclomethasone 30.6% vs. placebo 65.8%, P < 0.01) or developed BPD (beclomethasone 42.4% vs. placebo 69.4%, P < 0.03). We conclude that early-inhaled beclomethasone therapy was associated with a reduction in pulmonary inflammation after 1 week of therapy. Beclomethasone-treated infants with moderately elevated baseline IL-8 levels received less subsequent systemic glucocorticoid therapy and had a lower incidence of BPD than nontreated infants.

Administration, Inhalation↗

Differential sensitivity to acute cholesterol lowering of activation mediated via the high-affinity IgE receptor and Thy-1 glycoprotein.

Lateral cross-linking of transmembrane high-affinity IgE receptors (FcepsilonRI) or glycosylphosphatidylinositol-anchored Thy-1 glycoproteins on the surface of rat mast cells and rat basophilic leukemia (RBL) cells triggers the signaling pathways that lead to the release of allergy mediators. Although both of these pathways are initiated by an increased activity of Lyn kinase, the exact mechanism by which Lyn kinase interacts with aggregated FcepsilonRI and Thy-1 is not completely understood. Here we demonstrate that pretreatment of RBL cells with methyl-beta-cyclodextrin (MBCD) resulted in a dose- and time-dependent decrease in cellular cholesterol, increased detergent solubilization of Thy-1 and Lyn kinase, and a transient increase in tyrosine phosphorylation of several proteins. Acute lowering of cholesterol suppressed the activation through Thy-1, as determined by tyrosine phosphorylation of Syk kinase and some other proteins, and modulation of free cytoplasmic calcium. In contrast, the FcepsilonRI-mediated activation events were more resistant. Thy-1 and FcepsilonRI in MBCD-pretreated cells also differed in the extent of aggregation after cross-linking: Thy-1 formed large caps, whereas FcepsilonRI accumulated in small patches. MBCD treatment induced an increased release of secretory components in both Thy-1- and FcepsilonRI-activated cells. The combined data indicate that cholesterol depletion does not merely block receptor signaling but has more complex consequences.

Animals↗

The epithelium of the excretory duct of the human submandibular gland: a transmission and scanning electron microscopic study.

The duct of the human submandibular gland (Wharton) is lined by a pseudostratified epithelium consisting of principal and basal cells. Scattered among them are a few goblet and ciliated cells. The principal cells are columnar in shape with many mitochondria, numerous dense bodies and a central nucleus with some indentations. Their apical cytoplasm shows a number of clear vesicles, some of which are reactive to silver and are extruded by exocytosis into the lumen. Other vesicles, which are unreactive, may represent the products of the absorption process. A mechanism of apocrine secretion is also observed in the principal cells. Thus, with regard to its functions, the duct of the human submandibular gland modifies the composition of saliva by adding a secretory component to it. This latter material is derived from the goblet cells but chiefly from merocrine (exocytosis) and apocrine secretion of principal cells.

Adult↗

Peptide-containing nerves in labial salivary glands in Sjögren's syndrome.

OBJECTIVE: The presence and spatial distribution of peptide-containing nerves in labial salivary glands from 10 Sjögren's syndrome patients were compared with those in salivary glands from 7 healthy controls. METHODS: Immunoperoxidase staining was used to demonstrate vasoactive intestinal peptide (VIP)-immunoreactive (IR) fibers, postganglionic sympathetic fibers containing the C-flanking peptide of neuropeptide Y (CPON), and sensory fibers containing calcitonin gene-related peptide (CGRP) and substance P. RESULTS: Acini, intralobular ducts, small arteries, and postcapillary veins were richly innervated by VIP-IR fibers, whereas CPON-, CGRP-, and substance P-IR fibers were restricted to blood vessels. Peptide-containing nerves were found surrounding, but not in the middle of, the highly inflamed mononuclear cell areas. CONCLUSION: This topologic distribution suggests involvement of VIP-IR fibers in vascular, motor, and secretory components of the reflex salivary secretion, whereas the distribution and the vasoactive actions of CPON, CGRP, and substance P suggest a role in the regulation of the salivary gland circulation, and thus of transcapillary flow. Excessive release may contribute to a neurogenic inflammation. Local depletion and absence of trophic neuropeptide stimuli may contribute to acinar atrophy.

C-Peptide↗

Rhabdoid meningioma: intraoperative diagnosis using smear preparation.

Tumors with rhabdoid morphology were first described by Beckwith and Palmer in 1978 as aggressive renal tumors in very young children. Subsequently, rhabdoid tumors and tumors with rhabdoid features have been described in many other organ systems and all tend to have a poor outcome no matter what the histogenesis of the original tumor. Rhabdoid cells are plump, with abundant eosinophilic fibrillary to hyaline cytoplasm and peripheral, vesicular, variably pleomorphic nuclei. Nucleoli are invariably present. While their morphology is well recognized in processed biopsy material, their presence on a smear preparation can be quite startling. A case is presented to highlight the appearance of rhabdoid cells on an intraoperative smear preparation of a rhabdoid meningioma. An accompanying secretory component added to the complex picture.

Aged↗

Rapid disappearance from serum of intravenously injected rat myeloma IgA and its secretion into bile.

Intravenously injected monoclonal rat IgA is first removed from rat serum at a very fast rate (93% in 4 h), then at a much slower rate (t/2 = 24 h). The rapid initial disappearance is thought to be due in part to secretion into rat bile. This was demonstrated by rat liver perfusions with semisynthetic medium containing diluted (1:200) IgA myeloma serum. During perfusion, the cannulated bile displayed increasingly high levels of this IgA, with a bile to medium ratio of 38 after 1 h of perfusion; at the same time, there was a 40% drop of the rat monoclonal IgA concentration in the medium, which was not observed for rat IgG2a and albumin. All of the monoclonal biliary IgA was bound to secretory component. The rat liver is thus able to actively secrete a monoclonal IgA from the circulation into bile against a strong concentration gradient.

Animals↗

Expression of receptors for IgA on mitogen-stimulated human T lymphocytes.

This study demonstrates that activation of human peripheral blood mononuclear cells (PBMC) by the T cell mitogens phytohemagglutinin (PHA) and concanavalin A (Con A) induces the expression of receptors for IgA without addition of IgA to the culture medium. Cells bearing receptors for IgA were determined by indirect immunofluorescence using human secretory IgA and fluoresceinated goat anti-human IgA or goat anti-secretory component antibodies. Among freshly isolated PBMC, 4.7 +/- 1.7% of T cells, 12.7 +/- 12.5% of B cells and 14.4 +/- 7.6% of monocytes were found to be IgA receptor positive. In unstimulated PBMC cultures the percentage of IgA receptor-positive cells slightly increased at 48 h and was more elevated after 7 days. In Con A-stimulated cultures 24.3 +/- 18.5% of the cells expressed receptors for IgA after 48 h. Then, the number decreased and rose again thereafter. PHA stimulation induced an increase of smaller magnitude with similar kinetics. Induction of receptor for IgA on activated T cells was demonstrated by double-labelling experiments showing more CD8+ than CD4+ cells with receptors for IgA among Con A-activated PBMC. Furthermore, PHA or Con A stimulation of B cell-depleted PBMC suspensions resulted in a marked increase of cells bearing receptors for IgA. Expression of these receptors was down-regulated by recombinant interferon-gamma (250 units/ml) and by prostaglandin PGE2 (100 nM) both on unstimulated and mitogen-activated PBMC. The receptor for IgA was distinct from the asialoglycoprotein receptor and did not cross-react with the poly-Ig receptor of epithelial cells. It was concluded that, in the absence of inducing exogenous IgA, T cell mitogens trigger the expression of receptors for IgA. Therefore, T cell activation is associated with the down-regulation of receptors for IgM and the increased expression of receptors for IgG, IgA and IgE.

Concanavalin A↗

Thy-1-mediated activation of rat basophilic leukemia cells does not require co-expression of the high-affinity IgE receptor.

The glycosylphosphatidylinositol (GPI)-anchored protein Thy-1 is one of the most abundant molecules expressed on the surface of rat mast cells and rat basophilic leukemia cells, RBL-2H3. Antibody-mediated aggregation of Thy-1 induces in these cells release of secretory components; so does aggregation of the receptor with high affinity for IgE (Fc epsilon RI). To examine whether there is any relationship between Thy-1- and Fc epsilon RI-mediated activation, we have isolated from mutagenized RBL-2H3 cells a variant cell line deficient in the expression of surface Fc epsilon RI, and analyzed its ability to be activated by an antibody to Thy-1. Northern and immuno-blot analyses revealed that the variant cells were deficient in the expression of a structural or a regulatory gene for Fc epsilon RI gamma subunit. The cells did not respond by release of secretagogues and protein-tyrosine phosphorylation to IgE and antigen and anti-Fc epsilon RI monoclonal antibody (mAb) but their response to anti-Thy-1.1 mAb and calcium ionophore A23187 was retained. Transfection of the cloned Fc epsilon RI gamma subunit into the variant cells restored the surface expression of Fc epsilon RI and responsiveness to both the antigen and anti-Fc epsilon RI mAb but had no effect on responsiveness to anti-Thy-1 mAb. The combined data indicate that aggregation of surface Thy-1 glycoproteins activates a metabolic pathway which is independent of the presence of Fc epsilon RI gamma subunit and surface expression of Fc epsilon RI.

Animals↗

Protein tyrosine kinase Syk is involved in Thy-1 signaling in rat basophilic leukemia cells.

Thy-1, a glycosyl-phosphatidylinositol-anchored surface glycoprotein, has been shown to possess transmembrane signaling capacity. In rat mast cells and rat basophilic leukemia cells (RBL) aggregation of surface Thy-1 with antibodies triggers a series of intracellular events, resembling those induced by aggregation of the high-affinity receptor for IgE (Fc epsilonRI), including tyrosine phosphorylation of multiple proteins and release of secretory components. Unlike the Fc epsilonRI-mediated activation, where both the membrane-associated protein tyrosine kinase (PTK) Lyn and the cytoplasmic PTK Syk are responsible for initiating the signaling cascade, only Lyn has been implicated in Thy-1-mediated activation in RBL cells. Here we report that Syk is also rapidly tyrosine phosphorylated upon Thy-1 cross-linking. Increased Syk tyrosine phosphorylation is observed only in cells in which extensive aggregation of Thy-1 is induced by two layers of cross-linking reagents. RBL-derived mutant cells deficient in the expression of surface Thy-1 and transfectants re-expressing surface Thy-1 were used to exclude the possibility that Syk activation reflects an interaction of the cross-linking reagents with surface molecules other than Thy-1. As Fc epsilonRI gamma subunits are well known to promote activation of Syk and its recruitment to membrane complexes, we also investigated the role of these subunits in Thy-1-mediated Syk activation, using RBL-derived mutant cells deficient in the expression of Fc epsilonRI gamma subunits and their revertants. Consistent with the lack of Fc epsilonRI expression, no IgE-induced response could be elicited, while Thy-1-inducible Syk phosphorylation was preserved. Our results suggest that Syk might be one of the kinases responsible for signal propagation upon Thy-1 cross-linking in a Fc epsilonRI-independent pathway.

Animals↗