Number of C-bands of human isochromosome Xqi and relation to 45,X mosaicism

With combination of C and G banding techniques, three morphologically different types of isochromosome for the long arm of X (Xqi) have been identified, i.e. those with one C-band and symmetrical banding patterns of both arms, those with two C-bands and symmetrical banding patterns of two arms, and those with two C-bands but with asymmetrical banding patterns of two arms. The last type is a heterogeneous group with various different asymmetrical patterns. We have studied 6 cases of Xqi with C, G, and Q banding: 3 showed one C-band and symmetrical arms and all these were without 45,X mosaicism; the other 3 cases showed two C-bands, 2 of the cases having symmetrical arms and being mosaic for 45X/46,XXqi/47,XXqiXqi (those 2 were a pair of identical twins). One other had asymmetrical arms and was mosaic for 45,X/46,XXqi. Including our 6 cases, there have been a total of 30 reported cases of Xqi with C and G banding studies. Two-thirds of Xqi's were found to have 2 C-bands and one-third to have 1 C-band. Mosaicism was found in 85% of Xqi's with 2 C-bands and in only 44% of Xqi's with 1 C-band. Apparently, Xqi's with 2 C-bands have a greater tendency for anaphase lag and mitotic nondisjunction. Several possible mechanisms for the formation of the different types of Xqi's are discussed.     

Plurihormonal pituitary adenomas: immunostaining of all pituitary hormones is mandatory for correct classification

AIMS: We studied the clinicopathological characteristics of plurihormonal pituitary adenomas. METHODS AND RESULTS: The study material included 167 plurihormonal adenomas, which consisted of 31% of the surgically removed pituitary adenomas that we collected during a 12-year period. The mean age of patients with plurihormonal adenoma was 45.7 years (range 13-75 years). There were 86 men and 81 women. All tumours were fully classified by immunohistochemical staining for seven pituitary hormones or subunits. Thirty immunohistochemical subtypes of plurihormonal adenomas were recognized. Hormonal symptoms were present in 70% of patients, while serum hormonal levels were increased in 89% of patients. Most patients had symptoms related to only one of the hormones and only 7% of patients had symptoms related to two hormones. The most common hormonal symptom was acromegaly (50%); symptoms related to hyperprolactinaemia ranked second (20%). Double immunostaining of all the possible combinations of the hormones was performed in 30 selected tumours, and they all showed mixtures of hormones in individual adenoma cells in any hormonal combinations studied. The latter finding supported the view that plurihormonal adenomas are monomorphous adenomas. CONCLUSIONS: Plurihormonal adenomas are common pituitary adenomas. Immunohistochemical staining of all pituitary hormones is mandatory for correct classification.     

Human leukaemic T cells with complement receptors

Peripheral blood lymphocytes from a patient (EP) with lymphosarcoma cell leukaemia reported previously, had been found capable of forming sheep erythrocyte rosettes, reacting with T cell-specific antiserum and carrying surface immunoglobulins (Ig), IgM and IgD. It was suggested that the surface Ig were generated by leukaemic T cells due to activation of genes controlling synthesis of surface Ig. We here present evidence that these lymphocytes also carry complement receptors of B cells as detected by bovine erythrocyte–anti-bovine serum–complement complexes and by complement-coated zymosan. This study firmly establishes the presence of dual surface markers for T and B cells on the same leukaemic lymphocytes.     

The syndrome of ectrodactyly, ectodermal dysplasia and cleft lip and palate: report of a family demonstrating a dominant inheritance pattern

The syndrome of ectrodactyly, ectodermal dysplasia and cleft lip and palate (EEC syndrome) is described in a mother and 3 of her 4 children. Autosomal dominant inheritance was suggested in this family. However, genetic heterogeneity may exist in this syndrome. The significance of associated finClings, incluCling carcinoma of the cervix uteri, lacrimal duct stenosis and urinary tract strictures in patients with ectodermal dysplasia is considered.     

Specific and nonspecific immune factors in dental plaque fluid and saliva from young and old populations.

Separate samples of supragingival dental plaque overtly free of blood were centrifuged to obtain the free fluid phase (plaque fluid). Bound protein was eluted from the plaque bacteria and matrix by washing the plaque with a low-pH buffer. The plaque fluid, low pH eluate, and whole saliva were assayed for immunoglobulins A, G, and M, the third component of complement, lysozyme, lactoferrin, and lactoperoxidase. Concentrations of total protein and albumin were also determined. Antibody reactive with specific plaque bacteria was detected by indirect immunofluorescent microscopy. Specific and nonspecific immune proteins were present in plaque fluid from adult subjects at significantly greater concentrations than in their saliva, which suggests that these proteins are concentrated in dental plaque. The results indicate that both saliva and gingival exudate contribute to the immunological proteins found in the free fluid phase of dental plaque. The observation that immunoglobulin A antibody reactive with plaque bacteria could be detected in plaque fluid suggests that a wide variety of immunological reactions may occur in the dental plaque. These potential interactions between host, plaque bacteria, and their products could serve to influence the plaque flora and its ability to induce disease.     

Use of an immunoperoxidase method for identification of Bacteroides fragilis.

An indirect immunoperoxidase (IP) slide test was evaluated for the laboratory identification of Bacteroides fragilis. Antigen-antibody complexes were detected with goat anti-rabbit immunoglobulin G-peroxidase conjugate with 3-amino-9-ethyl-carbazole as the peroxidase substrate. Ninety-one percent of 44 B. fragilis strains tested were IP positive (3+ to 4+ reactions) with greater than or equal to 1:160 dilutions of rabbit antiserum produced against whole cells of B. fragilis ATCC 23745. The antiserum was species specific. No cross-reactions were observed with 35 Bacteroides strains of other species or with a variety of facultative or aerobic gram-negative bacilli. Four B. fragilis strains were IP negative. One of these (VPI 2393) was the deoxyribonucleic acid (DNA) homology group II reference strain. The other three were clinical isolates. IP-negative and representative IP-positive strains were tested for DNA homology with the type strains for DNA homology groups I and II (VPI 2553 and VPI 2393). Two of the three clinical isolates were classified as DNA homology group II, and the remaining strain was classified as a group I. Capsular material known to be unique to B. fragilis was common to both DNA homology groups as indicated by reactions with purified anticapsular antiserum. The IP technique provides a suitable alternative to fluorescent microscopy for the rapid immunological identification of B. fragilis.     

Bacteria induce osteoclastogenesis via an osteoblast-independent pathway

Bacteria or their products may cause chronic inflammation and subsequent bone loss. This inflammation and bone loss may be associated with significant morbidity in chronic otitis media, periodontitis, endodontic lesions, and loosening of orthopedic implants caused by lipopolysaccharide (LPS)-contaminated implant particles. Currently, it is not clear how bacteria or endotoxin-induced bone resorption occurs and what cell types are involved. Here we report that Porphyromonas gingivalis, a periodontal pathogen, and Escherichia coli LPS induce osteoclastic cell formation from murine leukocytes in the absence of osteoblasts. In contrast, stimulation with parathyroid hormone had no effect. These multinucleated, tartrate-resistant acid phosphatase-positive cells were positive for receptor activator of NF-kappaB (RANK), the receptor for osteoprotegerin ligand (OPGL), also known as RANK ligand (RANKL). Blocking antibodies demonstrated that their formation was dependent upon expression of OPGL and, to a lesser extent, on tumor necrosis factor alpha. Mononuclear cells represented a significant source of OPGL production. In vivo, P. gingivalis injection stimulated OPGL expression in both mononuclear leukocytes and osteoblastic cells. Thus, these findings describe a pathway by which bacteria could enhance osteolysis independently of osteoblasts and suggest that the mix of cells that participate in inflammatory and physiologic bone resorption may be different. This may give insight into new targets of therapeutic intervention.     

Expression of interleukin-1 in Reed-Sternberg cells and neoplastic cells from true histiocytic malignancies.

Interleukin-1, a peptide produced by monocytes, histiocytes, and interdigitating reticulum cells, plays an important role in the regulation of immune function. In this styde, we examined the production of interleukin-1 in 115 patients with a variety of human lymphomas by using a rabbit anti-interleukin-1 antibody and the immunoperoxidase technique. Interleukin-1 was detected in Reed-Sternberg cells from 20 patients with Hodgkin's disease as well as in neoplastic cells from 9 patients with true histiocytic lymphoma or malignant histiocytosis. In the other 86 cases, which included T- and B-cell lymphomas, no interleukin-1 could be detected. This result indicates a close relationship between Hodgkin's disease and true histiocytic malignancies and provides additional evidence to support our hypothesis that Reed-Sternberg cells are related to interdigitating reticulum cells.     

Point mutations in the P30 domain of the gag gene of Moloney murine leukemia virus

A series of point mutations in the P30 domain of the Moloney murine leukemia virus gag gene was generated by bisulfite treatment of heteroduplex DNAs containing a single-stranded region in the gag gene. One virus bearing such a mutation exhibited a coordinate defect in gag and pol function, and was similar to previously described deletion mutants with alterations in this gene. One mutant virus displayed a different phenotype: it could assemble virion particles and provide pol function, but the particles were defective in the early stages of infection. The continued concordance of the mutants' failure or ability to both assemble virions and provide pol lends further support to the proposal that similar parts of the gag gene are required for these two processes.     

Etiological diagnosis of influenza A virus by enzymatic radioimmunoassay.

An enzymatic radioimmunoassay for influenza A virus was developed by using polystyrene beads coated with rabbit immunoglobulin G to capture viral hemagglutinins (H1 and H3). Captured hemagglutinin was detected with goat immunoglobulin G followed by affinity-purified rabbit anti-goat immunoglobulin G labeled with alkaline phosphatase. [3H]AMP was added to quantify alkaline phosphatase activity, and free [3H]adenosine was measured with a scintillation counter. The assay detected as little as 0.1 ng of purified hemagglutinin. It was specific for hemagglutinin subtype and, depending on the source of the goat immunoglobulin G used, detected either H1 or H3. There was no reaction with neuraminidase or core antigens of influenza strain WSN-33. The clinical efficacy of the assay was evaluated with sequential nasal washes from 33 patients with naturally acquired H1N1 influenza. In the first 3 days of infection, the assay was consistently less sensitive than the viral culture, although detectable antigen persisted in secretions longer than did the infectious virus. Testing of multiple samples greatly increased the number of individuals in whom an etiological diagnosis could be made by immunoassay (81% of patients were positive for viral antigens at some point in their illness), and such testing was necessary to achieve the sensitivity of a single culture. Mean antigen levels were highest in nasal washes with the highest titers of infectious virus.