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B L Hansen

Publications and source records attributed to B L Hansen.

At least 37 records · Page 2Linked to original sources
PubMed1990

Immunocytochemical localization and immunochemical characterization of an insulin-related peptide in the insect Leucophaea maderae.

Immunocytochemical tests with eight monoclonal antibodies against either bovine or human insulin and seven polyclonal antibodies against bovine insulin were carried out to determine the presence of insulin-like neuropeptides in the brain and affiliated neuroendocrine structures of the insect Leucophaea maderae. Reaction products identified in the brain, subesophageal ganglion, and corpus cardiacum-corpus allatum complex indicate the presence of materials resembling mammalian insulins in its antigenic properties. The immunostaining observed with monoclonal antibodies appears to indicate the occurrence of an insulin-related peptide that shows sequential similarities with parts of both the A- and B-chains of mammalian insulin molecules. These suppositions are supported by the results of dot-blot and two-site time-resolved immunofluorometric assay (TRI-IFMA) screenings of fractions of Leucophaea tissue extracts obtained by chromatography. The polyclonal antibodies yielded reaction products in some of the same areas and in additional parts of the neuroendocrine system not visualized by the monoclonal antibodies. Immunoreaction was observed in the following areas: the pars intercerebralis of the protocerebrum, the nervi corporis cardiaci I transporting insulin-like material to the corpus cardiacum, the dorsolateral protocerebral area and the optic lobes, the deutocerebrum, the tritocerebrum, and the subesophageal ganglion. In addition, smaller cell bodies with immunoreactive deposits occur at the border between proto- and deuto-cerebrum, and in the central area of the protocerebrum. The distribution of reactive material in the corpus cardiacum-corpus allatum complex after use of both groups of antibodies was the same.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Induction of experimental chronic Pseudomonas aeruginosa lung infection with P. aeruginosa entrapped in alginate microspheres.

Alginate-producing, mucoid P. aeruginosa is frequently found in the lungs of patients with cystic fibrosis (CF), where it causes a chronic infection. The importance of alginate in the pathogenesis was demonstrated by the ability to establish chronic P. aeruginosa lung infection in rats if P. aeruginosa entrapped in minute alginate-beads were inoculated transtracheally. Alginate beads containing P. aeruginosa were formed by nebulizing a suspension of seaweed sodium-alginate and P. aeruginosa into a calcium solution. The alginate bead method of establishing infection was compared to an agar-bead method and proved to be quantitatively similar after 4 weeks. The ability of the two methods to induce formation of precipitins, IgA and IgG antibodies against P. aeruginosa antigens, including outer membrane proteins, flagella, exoenzymes and alginate, was assessed by crossed immunoelectrophoresis, enzyme-linked immunosorbent assay and immunoblotting. The two methods of inducing infection were comparable and infected rats had significantly higher antibody response than rats inoculated with sterile beads. We suggest that the alginate bead model closely resembles the later stages of CF-lung infection and that it offers the theoretical advantage of using a substance which is chemically similar to the alginate produced in vivo by P. aeruginosa.

Agar↗
PubMed1989

Immunocytochemical localization and immunochemical characterization of an insulin-related peptide in the pancreas of the urodele amphibian, Ambystoma mexicanum.

The pancreas of the axolotl, Ambystoma mexicanum, was investigated by immunocytochemical methods for the presence of immunoreactivity to a number of antisera raised against mammalian insulins. All anti-insulin antisera tested revealed substantial amounts of reaction products confined solely to the aldehyde-fuchsinophilic B cells of the endocrine pancreas. The reactive cell population was detected by use of one polyclonal antiserum against bovine insulin and eight different monoclonal antibodies against insulins from various mammalian species. Six of these antibody clones have known specificity to sub-regions of the insulin molecule. Additionally, fractions of an ethanol-HCl extract of pancreatic tissue from Ambystoma was studied in both conventional dot-blot tests by means of the same panel of antibodies and a two-site sandwich time-resolved immunofluorometric assay for human insulin involving two of the monoclonal antibodies. These experiments support the immunocytochemical observations by demonstrating the existence of an insulin-related peptide with a great deal of structural resemblance to mammalian insulins and displaying antigenic determinants in common at least with the amino acid residues A8-10 and B26-30. In conclusion, we interpret the findings as indicating that the immunocytochemically revealed tissue bound antigen in the Ambystoma pancreatic B-cells may be a peptide related to human insulin.

Ambystoma↗
PubMed1989

Hypertension is not a complication in cyclosporine-A monotherapy.

The course of blood pressure and antihypertensive treatment (AHT) was studied in 27 renal transplant recipients immunosuppressed with cyclosporine-A (CyA) as monotherapy. At the time of transplantation 13 patients received AHT and 14 were normotensive. The final outcome of transplantation and CyA immunosuppression was 19 patients without AHT, 4 with reduced AHT and 3 with unchanged doses of AHT, while in 1 case a de novo mild hypertension necessitated diuretic treatment.

Adult↗
PubMed1989

Pituitary-cell autoantibody diversity in sera from patients with untreated Graves' disease.

Sera from 22 untreated patients with recently diagnosed Graves' disease (GD) were screened in an immunocytochemical tissue assay for presumptive pituitary IgG autoantibodies, as defined by the presence of immunoreaction with rat and swine pituitary cell types. Forty four patients with Hashimoto's thyroiditis (HT) and 97 healthy subjects were also studied. Anti-pituitary antibodies were found in 14 of the 22 GD sera (64%). Of these, 6 sera reacted with cytoplasmic components of growth hormone (GH) cells, 3 with prolactin (PRL) cells, and 5 with both GH and PRL cells. Yet, none of the immunoreactive sera reacted with human GH, bovine PRL or TSH in dot-blot assays and absorption studies. Anti-pituitary antibodies also occurred in 4 of the 44 HT patients (9.1%) and in 9 of the 97 healthy subjects (9.2%). The frequency of sera revealing anti-pituitary antibodies was significantly higher in patients with GD compared to the groups of HT patients (P less than 0.00005), and healthy subjects (P less than 0.00005). Healthy subjects and patients with HT had a similar frequency of anti-pituitary antibodies (P = 1.0000). These data demonstrate that in thyroid autoimmune conditions antibodies reactive with cytoplasmic components of pituitary GH/PRL cells, may be present in sera from patients with GD. The pathological importance of this observation is at present unknown.

Adolescent↗
PubMed1988

Diversity of prolactin systems in the insect Leucophaea maderae: use of antiserum polyclonality for immunocytochemical detection of neuropeptide heterogeneity.

The presence of prolactin-like neuropeptides was demonstrated immunocytochemically in the brain and affiliated neuroendocrine structures of the insect Leucophaea maderae. Use of the unlabelled peroxidase-antiperoxidase method of Sternberger revealed a rather widespread and differential distribution of reaction products resembling human (hPRL) and ovine (oPRL) prolactin. Tests with antirat PRL antibody were negative. The specificity of the antibodies used was established by liquid-phase absorptions and confirmed in tissue control systems. In L. maderae, anti-oPRL identifies part of an oPRL-like molecule different from human and rat PRL. Anti-hPRL reveals part of a human and ovine PRL-like molecule different from rat prolactin. These results indicate the occurrence, in the nervous tissue of one insect species, of at least two types of prolactin-like molecules.

Animals↗
PubMed1988

Bacterial urinary tract infection in cyclosporine-A immunosuppressed renal transplant recipients.

Urinary tract infection and rejection in 48 renal transplant patients immunosuppressed with cyclosporine-A monotherapy were analysed. Urinary tract infection was diagnosed in 52% of the cases with Escherichia coli dominating. Urinary tract infection took a mild and relatively uncomplicated course as only one case of graft pyelonephritis caused graft nephrectomy and no influence on graft survival was observed (p greater than 0.05) in the infected cases in contrast to rejection episodes which caused a significantly reduced graft survival (p less than 0.01).

Aged↗
PubMed1987

Gastrin/CCK-like immunoreactivity in the corpus cardiacum-corpus allatum complex of the cockroach Leucophaea maderae.

By use of immunocytochemistry, a gastrin/CCK-like material has been demonstrated in the corpus cardiacum-corpus allatum complex of the cockroach Leucophaea maderae. Reactivity toward gastrin and CCK with region-specific antisera suggests that the gastrin/CCK-like peptide of this insect contains the COOH-terminal tetrapeptide sequence which is common to gastrin and CCK, and that the material is more gastrin-like than CCK-like. The results indicate that, like other neuropeptides, the gastrin/CCK peptide family appeared early in evolution within neuronal elements, and that the COOH-terminal region of gastrin has been conserved during phylogeny.

Animals↗
PubMed1987

Insulin-, glucagon- and somatostatin-like immunoreactivity in the endocrine pancreas of the lungfish, Neoceratodus forsteri.

The endocrine pancreas of the Australian lungfish, Neoceratodus forsteri, was investigated immunocytochemically for the presence of polypeptide hormone-producing cells. Three cell types were identified, namely insulin-, glucagon-, and somatostatin-immunoreactive elements. The insulin cells are confined solely to the center of the islets. Glucagon and somatostatin cells are distributed peripherally around the central mass of the insulin cells. Isolated cells or clusters of glucagon and somatostatin cells are also dispersed within the exocrine parenchyma. The immunoreactive cell types are compared with those staining with standard histological procedures. The spatial relationships of the different cell populations are examined.

Animals↗
PubMed1987

Graft failure and graft nephrectomy without severe complications.

The courses of 34 graft failures leading to graft nephrectomy in 19 patients were examined retrospectively. Cyclosporin (CsA) was the sole immunosuppressive in 70% of the cases, and azathioprine-prednisolone in 30%. Having diagnosed graft failure, the immunosuppressive treatment was continued for about 2-3 months and then tapered slowly. No deaths related to graft failure were recorded. In three cases a delay in graft nephrectomy caused complications such as sepsis and coagulopathy. We conclude that continuing immunosuppression a few months after having diagnosed graft failure may postpone or avoid graft nephrectomy while steroid withdrawal symptoms do not complicate the course at the time of graft failure.

Adolescent↗
PubMed1986

Localisation of oxytocin, vasopressin and parts of precursors in the human neonatal adrenal.

Being a possible alternative source for the production of vasopressin (AVP) and oxytocin (OXT), a study was undertaken of the fetal adrenal. The concentrations of these peptides within the fetal adrenal turned out to be low, viz., approx. 1 pg/mg in the rat and within the pg/g range in the human. Immunocytochemistry was performed either on conventional autopsy material kept till 12 years in paraffin blocks, or on more recently obtained formalin or glutaraldehyde-paraformaldehyde fixed material. In both types of material staining was good. In order to localize AVP cells, anti-AVP, an antibody against its associated neurophysin (anti-NSN) or an antibody raised against the c-terminal glycopeptide part of the AVP precursor (anti-GP) was used. OXT cells were localized by means of anti-OXT or an auto-antibody of a multiple sclerosis patient (auto-MS) probably recognizing OXT-neurophysin. The antibodies were characterized on human and rat brain material. In the external zone of the definitive cortex, apart from parenchyma cells, anti-AVP, anti-NSN and anti-GP stained fibre-like structures running in the connective tissue septa and around parenchyma cells and the cytoplasma of these cells. Anti-OXT and auto-MS stained droplets in the cytoplasm of the fetal zone cells. Similar distinct staining patterns for AVP and OXT cells were obtained in human anencephalics. These observations show that the peptides are not derived from the fetal brain, but are rather produced in the fetal adrenal cortex.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Glands↗