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Biomedical subjects

J A Reed

Publications and source records attributed to J A Reed.

72 records · Page 4Linked to original sources

Rapid colorimetric detection of epidermal growth factor receptor mRNA by in situ hybridization.

We describe a rapid, formamide-free, random oligomer-enhanced in situ hybridization method in formalin-fixed, paraffin-embedded tissue sections using a biotinylated oligonucleotide probe for colorimetric detection of the mRNA transcript of the epidermal growth factor receptor (EGFR) gene, a putative protooncogene. Transitional cell carcinomas (TCC) of the urinary bladder and oral squamous cell carcinomas (SCC) were examined. A431, a human squamous carcinoma cell line that overexpresses EGFR mRNA, and mature skeletal muscle, known to express EGFR, served as control tissues. A biotinylated poly-T oligonucleotide probe was used to evaluate the preservation of mRNA in the formalin-fixed, paraffin-embedded tissues. The EGFR mRNA and poly-T oligonucleotide probes were constructed with a target-specific, 5' region and a 3' non-hybridizing, biotinylated tail. Random sequence oligomers nine bases long added to the probe cocktail eliminated the need for formamide and sheared carrier DNA in the method. The assay produced strong, specific staining for EGFR mRNA in all cases of TCC and SCC, and in the A431 tumors, but not in skeletal muscle. The assay was completed in approximately 90 minutes. This method may have widespread utility for rapid and specific detection of other mRNA sequences.

Base Sequence↗

Elicitation of a predominantly lambda light chain-bearing antibody response in BALB/c mice to a novel bifunctional aminocarboxylate chelating agent.

A panel of murine monoclonal antibodies has been raised against the aminocarboxylate bifunctional chelating agent PA-DOTA complexed with Samarium. Ninety percent of the antibodies (43 of 48) used a lambda light chain. The binding specificity of 11 of the antibodies was examined by competition assays using several structurally related aminocarboxylate chelating agents containing different metals. Most of the antibodies are directed against the macrocycle ring of PA-DOTA and require the presence of a metal within the structure for binding.

Animals↗

Benign trichogenic tumours: a report of two cases supporting a simplified nomenclature.

We report two cases of a rare benign tumour of hair germ. Clinically, both were solitary, well-circumscribed, subcutaneous nodules located in the extremities. Histologically, the tumours were characterized by nests and thin cords of basaloid epithelial cells intimately associated with a cellular stroma. The basaloid cells exhibited peripheral palisading, keratinization in the form of keratotic cysts and squamoid transformation, and pilar differentiation. An unusual, but distinctive, cribriform pattern of growth was observed. There was no communication with the overlying epidermis. Abundant primitive hair germinal buds and rare more advanced abortive hair follicles were identified. These histological appearances encompass features of both trichoblastic fibroma and trichogenic trichoblastoma, thus distinguishing these neoplasms from other skin tumours and reinforcing the hypothesis that these tumours are closely related from a histogenetic point of view. The presence of overlapping histological features can be problematic for practising histopathologists who rarely encounter these conditions. With this in mind, the term benign trichogenic tumour may be more appropriate to encompass these two tumours and related neoplasms that appear to lie within the spectrum of hair follicle development.

Adult↗

Immunomycology: rapid and specific immunocytochemical identification of fungi in formalin-fixed, paraffin-embedded material.

We report the rapid (less than 1 hr), immunocytochemical identification of various fungi in formalin-fixed, paraffin-embedded tissues using antisera originally developed for use in immunodiffusion assays. Primary antisera directed towards fungal genera including Aspergillus, Blastomyces, Candida, Coccidioides, Cryptococcus, Histoplasma, and Sporothrix were examined. The specificity of each antiserum was evaluated by the presence or absence of crossreactivity with other morphologically similar fungi in both paraffin-embedded pure fungal cultures and tissues with culture-confirmed fungal infections. Each antiserum reacted strongly with the fungus to which it had been raised, whether examined in pure culture or infected tissues. The antisera raised against Candida, Cryptococcus, and Sporothrix did not exhibit cross-reactivity with any other fungus tested. However, the antisera raised to Aspergillus, Blastomyces, Coccidioides, and Histoplasma demonstrated significant crossreactivity with other genera of fungi, thus precluding their routine use in diagnostic immunocytochemistry. The results indicate that immunocytochemistry may provide an important adjunct to other methods, such as immunodiffusion or complement fixation assays and histochemical stains such as the Grocott methenamine silver or periodic acid-Schiff, when attempts are made to specifically identify certain fungi in formalin-fixed, paraffin-embedded tissues before mycology culture results are available.

Antigens, Fungal↗

Immunocytochemical identification of Rochalimaea henselae in bacillary (epithelioid) angiomatosis, parenchymal bacillary peliosis, and persistent fever with bacteremia.

We report the immunocytochemical identification of Rochalimaea henselae, a newly recognized fastidious, Gram-negative, Warthin-Starry-positive organism, as the common pathogen in bacillary angiomatosis (BA), bacillary peliosis (BP) of the liver and spleen, and persistent fever with bacteremia in immunocompromised patients. Immunogenic proteins of the R. henselae strain isolated from the blood of a febrile immunocompromised patient with BP of the liver were used to produce primary immune serum in rabbits. Using immunocytochemical procedures, the polyclonal antiserum reacted strongly not only with the immunizing strain of the bacteria, but also with other blood isolates of R. henselae (five cases) from both immunocompromised and immunocompetent patients and with the organisms present in the tissue lesions of cutaneous BA (five cases) and BP of the liver (two cases) and spleen (one case). The blood isolates and BA and BP tissue samples were obtained from widely separated geographic areas. The antiserum was weakly cross-reactive with cultures of Rochalimaea quintana, an organism closely related to R. henselae, but this reactivity was eliminated by specific adsorption. The antiserum did not cross-react with the Warthin-Starry-positive organisms associated with cat scratch disease (Afipia felis), syphilis (Treponema pallidum), Lyme disease (Borrelia burgdorferi) or chronic active gastritis (Helicobacter pylori). Likewise, the antiserum did not identify organisms in eight cases of Kaposi's sarcoma, a disorder of immunocompromised patients that is clinically similar to BA. Further studies are needed to determine the prevalence of this newly recognized organism as well as its possible involvement in other angioproliferative diseases.

Acquired Immunodeficiency Syndrome↗

Complete one-hour immunocytochemistry based on capillary action.

We describe a less than one-hour manual method for immunocytochemical analyses of B5 or formalin-fixed, paraffin-embedded tissue sections. The method employs capillary action to sequentially apply, incubate and remove liquid reagents from apposed pairs of up to 20 glass microscope slides and allows for simultaneous immunocytochemical analyses of as many as 10 different antigens. The method described here uses a) positively charged glass slides to rapidly immobilize tissue sections; b) rapid deparaffinization techniques; c) multipurpose reagents; d) ethanol-enriched buffer washes to improve capillary action and reduce nonspecific background; e) a single broad spectrum streptavidin-peroxidase or streptavidin-alkaline phosphatase detection system that identifies most primary monoclonal and polyclonal antibodies; and f) specific immunocytochemical signal amplification by cyclic chromogen enhancement.

Alkaline Phosphatase↗

Prenatal cocaine exposure fails to modify neurobehavioral responses and the striatal dopaminergic system in newborn rats.

1. The effects of cocaine on locomotor activity and striatal dopaminergic receptors and dopamine turnover were studied in rat pups exposed to cocaine (30 mg/kg/day) throughout the entire gestational period. 2. Prenatal exposure to cocaine did not alter the motor coordination or spontaneous locomotor activity in the offspring. 3. No change in the characteristics of dopaminergic receptors and the rate of dopamine turnover was detected in the striatum.

Animals↗

Effect of nicotine on central GABAergic system.

1. The acute and chronic effects of nicotine (1.5 mg/kg/day) on the striatal and mesolimbic GABAergic systems were examined in the rat. 2. Despite altering the striatal DAergic activity, neither acute nor chronic administration of nicotine significantly affected the GABAergic system. 3. The nicotine treatment did not alter the ability of muscimol to inhibit the hyperactivity elicited by apomorphine. 4. Similarly, the levels of GABA in striata and nucleus accumbens remained unchanged.

Animals↗

Acrocephalopolysyndactyly type II--Carpenter syndrome: clinical spectrum and an attempt at unification with Goodman and Summit syndromes.

Carpenter syndrome (ACPS type II) was first described by Carpenter in 1901. The syndrome consists of acrocephaly, soft tissue syndactyly, brachy- or agenesis mesophalangy of the hands and feet, preaxial polydactyly, congenital heart disease, mental retardation, hypogenitalism, obesity, and umbilical hernia. Here we review the literature on Carpenter syndrome and add 2 affected sibs with marked intrafamilial variability. This review showed that 2 reported variations of Carpenter syndrome, Goodman and Summitt syndromes, actually fall within the clinical spectrum of this disorder. This confirms earlier suggestions of Gorlin (personal communication 1982) and Hall et al [Am J Med Genet 5:423-434, 1980].

Acrocephalosyndactylia↗

A fluorescent dye which recognizes mature peripheral erythrocytes of myeloproliferative disorders.

Based on the previous finding that erythrocytes from patients with chronic myelogenous leukemia stain with the fluorescent dye merocyanine 540, erythrocytes from patients with other myeloproliferative disorders were examined for their ability to bind the membrane probe. As assessed by both fluorescence staining and a quantitative dye removal assay, all samples of erythrocytes from patients with chronic myelogenous leukemia, polycythemia vera, myelofibrosis with myeloid metaplasia and essential thrombocythemia bound more dye than did erythrocytes from normal, healthy individuals. Erythrocytes from three of six patients with acute myelogenous leukemia also showed increased affinity for the dye. In contrast, erythrocytes from three patients with acute lymphocytic leukemia and one with unclassifiable leukemia bound only normal amounts of dye. The procedures described may be useful as a supplemental aid to diagnosis of myeloproliferative disorders or for investigation of hematological diseases where multilineage involvement is suspected.

Cell Differentiation↗

Merocyanine 540 recognizes membrane abnormalities of erythrocytes in chronic myelogenous leukemia.

Merocyanine 540 is a fluorescent dye which stains erythrocytes that have lost their normal membrane phospholipid asymmetry. Because erythrocytes from patients with chronic myelogenous leukemia have been reported to display this abnormal phenotype, peripheral blood erythrocytes from such patients were examined for their ability to stain with the dye. Erythrocytes from all patients with active disease states stained, whereas neither erythrocytes from normal, healthy individuals nor from a patient whose disease symptoms were eliminated by chemotherapy stained. These results suggest that merocyanine 540 may have utility in the clinical evaluation of chronic myelogenous leukemia.

Adult↗

Characterization of protein kinases in mitotic and meiotic cell extracts.

A number of protein kinases have been separated and identified in extracts from mitotic and interphase culture cells and from mature and immature amphibian oocytes using nondenaturing polyacrylamide gel electrophoresis followed by in situ phosphorylation assays. Certain of these protein kinase activities appear to correlate with the biological activity of extracts, assayed by their ability to induce meiotic maturation following injection into Xenopus oocytes. These results are consistent with the notion that protein phosphorylation/dephosphorylation may be integral to the mechanisms of both nuclear membrane breakdown and chromosome condensation, events common and distinctive to mitosis and meiosis.

Animals↗

Injected mitotic extracts induce condensation of interphase chromatin.

Although extracts from mitotic cells have been shown to induce chromosome condensation when injected into amphibian oocytes, they have not as yet been shown to induce this response in somatic interphase cells. In the experiments reported here, when mitotic extracts were injected into syncytial frog embryos, whose somatic nuclei were arrested in interphase, chromosome condensation was observed. The inability of interphase extracts, injected at similar concentrations, to induce this event demonstrates the cell cycle-specific accumulation of the factors responsible.

Animals↗

Granulocyte-macrophage colony-stimulating factor and pulmonary surfactant homeostasis.

Pulmonary surfactant lining the alveolus of the lung is critical to postnatal adaptation to air breathing. Precise concentrations of surfactant proteins and lipids are maintained in the alveolar space by a careful balance among synthesis, recycling, and catabolism. Pulmonary alveolar proteinosis is a rare pulmonary disease associated with accumulation of surfactant lipids and proteins in the alveolar spaces. Recent work with transgenic mice demonstrated that disruption of the production of granulocyte-macrophage colony-stimulating factor (GM-CSF) or the common beta-subunit of the GM-CSF receptor caused alveolar proteinosis that was histologically similar to that seen in human patients. The defect in surfactant homeostasis is caused by decreased surfactant clearance, mediated (at least in part) by dysfunction of the alveolar macrophage. Local production of GM-CSF corrects the alveolar proteinosis in the GM-CSF knockout mouse. Likewise, transplantation of wild-type bone marrow cells expressing the common beta-chain of the GM-CSF receptor restores surfactant homeostasis in the GM-CSF receptor knockout mouse. These studies demonstrate the previously unanticipated role of GM-CSF signaling in surfactant homeostasis, mediated (at least in part) by its actions on the clearance of surfactant lipids and proteins by the alveolar macrophage. These findings may have important implications for the diagnosis and treatment of pulmonary alveolar proteinosis syndromes in humans.

Animals↗