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Induction of autolysis of staphylococci by the basic peptide antibiotics Pep 5 and nisin and their influence on the activity of autolytic enzymes.

Pep 5 and nisin are cationic bactericidal peptides which were shown to induce autolysis in Staphylococcus cohnii 22. In contrast to nisin, Pep 5 induced lysis could be stimulated in the presence of glucose. Addition of lipoteichoic acids (LTA) (D-alanine:phosphorus = 0.475:1) inhibited all effects of Pep 5 on susceptible cells in a molar ratio LTA:Pep 5 of 10:1. Treatment of S. cohnii 22 with Pep 5 or nisin for 20 min and subsequent washing with 2.5 M NaCl released autolysin activity. Crude preparations of the hydrolyzing enzymes produced free amino groups as well as polysaccharide fragments from the murein backbone, suggesting the presence of a muramidase or glucosamidase, and endopeptidase or amidase. Both enzyme activities were inhibited by lipoteichoic acid; they could be fully reactivated by addition of Pep 5 in sufficient concentrations. The velocity of hydrolysis was not influenced by nisin, whereas it was doubled in presence of Pep 5. The results are discussed in view of a possible mechanism of induction of lysis by Pep 5 and nisin.

Anti-Bacterial Agents↗

Malignant histiocytosis. Immunohistochemical characterization on paraffin embedded tissue.

Clinically, malignant histiocytosis is a malignant neoplasia with poor prognosis. Diseased are lymphnodes (especially cervical nodes), liver, spleen and bones. Few cases become leukemic. The cells show characteristic pale roundish, often indented nuclei, without large nucleoli and with abundant ill-defined cytoplasm. Phagocytosis of erythrocytes and leukocytes, as well as, hemosiderin deposits may serve as indicators for histiocytic, respectively macrophagic qualities. On touch preparation, tumor cells previously had been marked by acid phosphatase and non-spevific esterase, as being histiocytic. - A comparable marking could be carried out on paraffin embedded material with lysozyme (muramidase) and alpha1-antichymotrypsin, by the indirect immuno-peroxidase technique. No correlation could be proven between any special shape of tumor cells or between different grades of cellular atypism and presence or absence of the immunohistochemical reaction. The reaction with lysozyme and alpha1-antichymotrypsin was also tested in other tumors and was found to be positive in a variety of different tumor cells showing degenerative changes, respectively necrobiosis. - But lysozyme and alpha1-antichymotrypsin are markers characteristically found in histiocytes, respectively histiocytic tumor cells. They are apparently less distinct in MH with a larger number of immature histiocytic tumor cells.

Adolescent↗

Conditions for the immunohistochemical demonstration of complement factor C3 in formaldehyde-fixed and paraffin-embedded renal tissues.

Paraffin sections of formaldehyde-fixed renal biopsies were labeled for complement C3 by a polyclonal rabbit antibody to human complement C3, by the peroxidase-antiperoxidase complex (PAP) and the avidin-biotin peroxidase complex (ABC) techniques, respectively. All tissues had C3 deposits according to direct immunofluorescence on fresh frozen sections. Staining for muramidase was introduced as an intrinsic control for the degree of tissue proteolysis after the necessary trypsin digestion prior to the immunoenzyme labeling. The results indicated that even minute deposits of C3 could be detected in paraffin sections by the ABC method, which was more sensitive than the PAP technique; the ABC method allowed a maximal dilution of 1:2,400 of the primary antibody as compared to 1:800 for the PAP technique.

Animals↗

Proliferative activity of cells in the synovium as demonstrated by a monoclonal antibody, Ki67.

The presence of proliferating cells has been sought in the synovium of rheumatoid arthritic (RA) and osteoarthritic (OA) joints using the monoclonal antibody Ki67, which marks a nuclear antigen present in all stages of the cell cycle apart from Go. Synovia were studied from 21 RA and 14 OA cases using the indirect immunoperoxidase technique. Double-staining was performed on 18 RA and 17 OA synovia with the simultaneous labelling of lysozyme (muramidase) by the immuno-alkaline phosphatase method and with Ki67 by the indirect immunoperoxidase method. Most of the RA and OA synovia showed an absence of Ki67-positive cells in the intimal cell layer. Three RA and four OA synovia showed no more than ten proliferating cells in the whole of the intimal layer examined. Similar results were obtained when double-labelling was performed. Eight RA and six OA synovia showed the presence of occasional Ki67-positive cells in the intimal layer. The total number of intimal cells was measured for each histological section, and the proliferation index calculated as the percentage of total cells in the intimal layer showing Ki67-positive staining. This varied between 0.03% and 0.0033% (between 1:2800 and 1:30,000 cells). In contrast, there were plentiful Ki67-positive cells present in the lymphocytic infiltrate and around blood vessels in the RA synovia and in the synovial infiltrate, where present, in the OA cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗

Immunohistochemistry of so called "neoplastic angioendotheliosis".

Three cases of "neoplastic angioendotheliosis" were examined immunohistochemically by the peroxidase-antiperoxidase method for Factor VIII-related antigen and various leukocyte markers. In all three cases, the tumor cells stained positively for common leukocyte antigen. IgM, and kappa or lambda light chains were demonstrable in two cases. Stains for carcino-embryonic antigen and muramidase were negative. This indicates that the neoplastic cells in the lumen of blood vessels were of lymphoid origin.

Antigens↗

Reactions of vessel walls and brain parenchyma to the accumulation of Gaucher cells in the Norrbottnian type (type III) of Gaucher disease.

Splenectomy in children with the Norrbottnian type of Gaucher disease is followed by increased blood levels of glucosylceramide and impaired neurological and mental status. High blood levels are associated with an increased accumulation of glucosylceramide in perivascular Gaucher cells in the brain compared to non-splenectomised cases. Surrounding the Gaucher cell infiltrates there is loss of neurons and slight demyelination in the brain parenchyma. The brains of four cases with the Norrbottnian type of Gaucher disease were examined by immunohistochemical stains in an attempt to further characterize the perivascular Gaucher cells and to examine the reactions of the vessel walls and brain parenchyma to the accumulation of Gaucher cells. The perivascular storage cells showed granular staining with antibodies to muramidase and alpha 1-anti-chymotrypsin confirming that they are blood-derived macrophages belonging to the monocyte-macrophage system. The Gaucher cells contained material positive for antisera to plasma proteins strongly suggesting that large molecules (including glucosylceramide) can escape from the blood and be taken up by the macrophages in Gaucher disease. The storage cells were surrounded by a reticulin network stained by antisera to collagen type III, type IV and laminin. The infiltrates were bounded from the brain parenchyma by a membrane strongly positive with antiserum for the basal lamina protein collagen type IV and laminin. The formation of a basal lamina around the Gaucher cell cuffs probably constitutes a protective phenomenon governing the brain parenchyma against the foreign cells. A focal loss of neurons but only minor loss of axons could be demonstrated with the antiserum to neurofilament.(ABSTRACT TRUNCATED AT 250 WORDS)

Astrocytes↗

Lectin I of Ulex europaeus as a marker for a subset of histiocytic tumours of the lymph node.

We describe four lymph node based tumours in which numerous neoplastic cells and some mitotic figures were characterized by staining affinity for Lectin I of Ulex europaeus (UEA-I). The patients had no vascular or epithelial tumours and presented symptoms suggestive of a systemic lymphoproliferative disease. Histologically, the tumours were composed of large, cohesive, cells which were mainly located in the paracortex. UEA-I reactivity was more evident in the Golgi area and was present in large mononucleated cells often arranged to delimit vascular-like spaces. The neoplastic cells were weakly muramidase-positive in one case, and were ANAE+/AP+ in two other cases. Large dots of UEA-I reactivity were detected in S-100+/muramidase-negative Langerhans-like cells present in one case of Letterer-Siwe disease. UEA-I staining was consistently negative in 20 cases of B cell- or T cell lymphoma and in 9 other cases of histiocytic lymphoma. It is suggested that UEA-I+ tumours of the lymph nodes are part of a distinct subset of histiocytic malignancies whose neoplastic cells present some morphological and phenotypic properties normally associated with endothelial cells.

Adolescent↗

Granular cell tumour of the mammary gland simulating malignancy. A report on two cases with light microscopy, transmission electron microscopy and immunohistochemical investigation.

Primary granular cell tumours of the breast in 35 and 55 year old women were studied by light microscopy, transmission electron microscopy and immunohistochemistry. Light and electron microscopy revealed a neural origin of the tumours and this was further substantiated by immunohistochemical studies, with positive S-100 protein reaction and negative reactions for surface heavy and light chains, CEA, alfa-1-antitrypsin, muramidase and GFA-protein. Granular cell tumour of the mammary gland is a very rare tumour. Clinically it sometimes simulates carcinoma because of its fibrous consistency, fixation to pectoral fascia and skin retraction. The diagnosis of granular cell tumour should be included in the differential diagnosis of carcinoma of the breast. The granular cell tumour is derived from neuro-ectodermal tissue. Whether it represents a neurogenic cell-confined metabolic disturbance with lysosomal activation, or a true neoplasm remains to be elucidated.

Adult↗

Reversion of Lactobacillus lactis protoplasts.

More than 99% of L. lactis cells have been converted to protoplasts upon digestion of cell walls with mutanolysin (N-(acetyl)muramidase). Functional protoplasts were obtained even with the lowest level of the enzyme that was used (0.1 U.ml-1 of the cell suspension) and after incubation at 37 degrees C for 2 min. The regeneration of the polymerized cell wall appears to be induced by a cell homogenate of the same organism.

Cell Wall↗

Lymph Node Reaction to Cancer. (Immunohistochemical and Ultrastructural Study).

A total of 153 regional lymph nodes obtained from 50 patients, operated for gastric, lung, breast, colonic and cervical cancers, were studied. Immunohistochemical methods were used to detect different markers and enzymes (CD1, CD2, CD3, CD4, CD8, CD20, CD30, CD35, CD45, l light Ig chain, lysozyme (muramidase), a-1-antichymotrypsin, protein S100 and FVIIIR). Results indicate that failure of local immunity is explained by the followings: 1. decrease in the total number of T-cells (suppressors as well as helpers); 2. high number of B-cells, plasmoblasts and antibody-forming plasmocytes, know to be able to block the cytotoxic T cells; 3. decrease in the number of incoming free phagocytes of monocytic origin and reduction in the phagocytic activity of fixed macrophages (sinus histiocytes); 4. high functional activity of dendritic reticulum cells; 5. non-handled stimulation 6. reduction in area of postcapillary venules and impairment of lymphocyte recirculation through them.

Journal Article↗

Tumor necrosis factor-alpha is expressed by monocytes/macrophages following cardiac microembolization and is antagonized by cyclosporine.

The time course of expression of TNF-alpha in myocardial wound healing following ischemic injury was investigated in the porcine heart. Microembolization was used to induce focal ischemia and necrosis in hearts of 39 adult pigs. The animals were sacrificed after 3, 6, 12, 24 h, 3 and 7 days, and after 4 weeks, and the myocardial tissue was studied by immunofluorescence using specific antibodies. TNF-alpha containing cells were identified as monocytes/macrophages by double staining with a muramidase antibody. Monocytes/macrophages were the only source of TNF-alpha. Microembolization caused multiple necrotic foci with loss of myocytes in the left ventricular myocardium. These foci contained numerous monocytes/macrophages and showed an inflammatory reaction typical of wound healing followed by replacement with scar tissue. The number of TNF-alpha positive cells increased after 24 h, peaked between 3-7 days and slowly decreased thereafter. Expression of TNF-alpha in monocytes/macrophages was significantly reduced after pretreatment of pigs with cyclosporine or dexamethasone. It is concluded that 1.) in myocardial tissue monocytes/macrophages are the only cell type expressing TNF-alpha, 2.) TNF-alpha is involved in wound healing after ischemia, and 3.) synthesis of TNF-alpha and inflammatory angiogenesis can be inhibited be treatment with either cyclosporine or dexamethasone.

Animals↗

The mitogenicity for murine splenocytes of specific surface components of the oral periodontopathic bacterium, Actinomyces viscosus.

Many characterized fractions obtained from A. viscosus were examined to identify the macromolecules responsible for mitogenicity for lymphocytes. Spleen-cell suspensions of CBA/J mice were cultured with 50-200 micrograms dry weight of A. viscosus strains T14V and T14AV cellular components. Lipopolysaccharide (LPS) (Escherichia coli) was used as a positive control. Mechanical disruption with a French pressure cell or sonication produced preparations with a stimulation of 69,082 and 45,183 counts above background (CAB), respectively. Mitogenic activity was also present in the culture supernatant (38,000 CAB). Other poorly mitogenic fractions included the peptidoglycan, cell-wall fractions, muramidase digests of cell walls, and the microcapsule extracted from whole cells with 0.5 M MgNO3. The results suggest that mitogenic activity is not associated with the isolated cell-wall structure. The activity was released from the cell surface by physical shearing forces, as well as released into the medium growth.

Actinomyces↗

Methylprednisolone attenuates inflammation, increase of brain water content and intracranial pressure, but does not influence cerebral blood flow changes in experimental pneumococcal meningitis.

We investigated the effect of methylprednisolone on pathophysiological alterations in experimental pneumococcal meningitis. Untreated rats injected with pneumococcal cell wall components after hydrolization with M1 muramidase (PCW-M) developed an increase of regional cerebral blood flow (rCBF; 165.0 +/- 12.8%, baseline 100%, mean +/- S.E.M.), brain water content (79.23 +/- 0.10%), intracranial pressure (ICP; 11.9 +/- 1.0 mmHg) and white blood cell (WBC) count in the cerebrospinal fluid (CSF) (2,709 +/- 482 cells/microliters) within 8 h after intracisternal (i.c.) challenge. Pretreatment with methylprednisolone or administration of methylprednisolone 4 h after i.c. challenge significantly attenuated the increase of brain water content (78.88 +/- 0.08% and 78.82 +/- 0.05%, resp.), ICP (7.7 +/- 1.1 mmHg and 4.9 +/- 0.8 mmHg, resp.) and CSF WBC count (1,257 +/- 168 cells/microliters and 976 +/- 105 cells/microliters, resp.). However, methylprednisolone did not inhibit the increase of rCBF (163.5 +/- 13.7% and 160.9 +/- 6.8%, resp.), whereas dexamethasone significantly attenuated microvascular changes. Hypercapnia-induced reactivity of cerebral vessels tested 8 h after i.c. injection was preserved in all groups. In conclusion, we found that methylprednisolone significantly attenuated the increase of brain water content, ICP and CSF WBC count, but had no effect on microvascular changes during the early phase of experimental pneumococcal meningitis.

Animals↗

Osteosarcomas and chondrosarcomas of the jaws: immunohistochemical correlations.

Clinical, microscopic, and immunohistochemical characteristics of 17 jaw sarcomas are reported. Histologic subtypes included chondroblastic (five), fibroblastic (five), osteoblastic (three), telangiectatic (one), parosteal (two), and chondrosarcoma (one). Reactivity for all antigenic markers in decalcified tissue was judged to be comparable to nondecalcified tissue. All neoplasms were nonreactive for muramidase and leukocyte common antigen. alpha-1 Antichymotrypsin and HLA-DR immunoreactivity was found focally. Positive S-100 staining was found predominantly in chondrocytes. All tumors were positive for vimentin. Cells in focal zones of cartilage were positive for keratin. No distinctive pattern emerged relative to clinical recurrence and histologic subtype or immunotype. Leukocyte common antigen determinations were useful because they distinguished between neoplastic and inflammatory cells. S-100 protein stains helped in the subclassification of chondroblastic osteosarcoma, and vimentin stains confirmed mesenchymal origin. Cross-reactive staining of cartilage with keratin antibodies was regarded as a possible diagnostic pitfall.

Adolescent↗

Oral granular cell tumors: a clinicopathologic and immunocytochemical study.

To investigate the histogenesis of the granular cell, a large series of granular cell tumors was studied for clinical and histopathologic features with emphasis on immunocytochemical markers. The nongingival granular cell tumors (NGGCT) were found to be more prevalent among females than males by a ratio of 2:1 and arose on the tongue (67%), the buccal mucosa (13%), the lips (8%), the soft palate (6%), and other sites (6%). With the use of the avidin-biotin-peroxidase method, polyclonal rabbit antisera were employed. The antisera were directed to the following antigens: S-100 protein, myoglobin, myosin, actin, desmin, alpha-1-antitrypsin, and muramidase. Results indicated that granular cell tumors are not homogenous for immunocytochemical markers. Nongingival granular cell tumors were universally positive for S-100 protein and failed to exhibit immunoreactivity for myogenous or histiocytic markers. Alternatively, the gingival granular cell tumor of infancy was negative for all markers, whereas rhabdomyoma was reactive with myogenous markers and a subpopulation of tumor cells displayed S-100 protein immunoreactivity. The granular cell ameloblastoma was reactive only with antiserum to alpha-1-antitrypsin. Ultrastructurally, granular cells from one of two NGGCT showed a direct evolution from skeletal muscle fibers. It is concluded that the oral NGGCT is a tumor positive for S-100 protein that may arise from muscle or nerve sheath.

Adolescent↗

Malignant fibrous histiocytoma of the uterus.

A primary, malignant pleomorphic giant cell tumor of the uterus was studied by light and electron microscopy. The tumor was characterized by spindle cells, plump epithelioid cells, pleomorphic giant cells, osteoclast-like giant cells, and foamy xanthomatous cells. Histochemically, tumor cells did not show either myogenic or epithelial characteristics. Immunohistochemically, tumor cells were devoid of evidence of desmin, cytokeratin, myoglobin, and lysozyme (muramidase), but vimentin was weakly positive, and alpha 1-antichymotrypsin was weakly positive in the cytoplasm of pleomorphic giant cells. Ultrastructurally, tumor cells did not show either myogenic or epithelial features, but they resembled a variant of malignant fibrous histiocytoma. The present case was classified as a storiform-pleomorphic and giant cell type of malignant fibrous histiocytoma of the soft tissues. The uterus is considered to be an additional possible site of malignant fibrous histiocytoma.

Female↗

Establishment and characterization of a new permanent cell line (GDM-1) from a patient with myelomonoblastic leukemia.

The GDM-1 permanent cell line was established from the peripheral blood of a patient with a Philadelphia chromosome negative myeloproliferative disorder, after transformation to acute myelomonoblastic leukemia. The GDM-1 cells exhibited the same characteristics as those isolated from the peripheral blood of the patient prior to death: cells contained non-specific esterase sensitive to fluoride, myeloperoxidase, lysozyme (muramidase), and exhibited both Fc and complement (C3) receptors but lacked B- and T-cell surface markers including T-associated antigens. E-rosetting capacity, surface and intracytoplasmic immunoglobulins and EBV determined nuclear antigen (EBNA). The GDM-1 cells bore the 1a receptor and the myeloid leukemia antigen (M-1). The karyotype of the cultured leukemic cells showed the same specific chromosomal abnormalities present in the monoblasts obtained from the peripheral blood prior to death, indicating that the cell line was derived from the original leukemic cells.

Aged↗

Purification of the proteinase from group B streptococci that inactivates human C5a.

We previously reported that group B streptococci (GBS) possess a cell-associated activity that inactivates the chemotactic activity generated in zymosan-activated serum by cleaving a specific site within the carboxy termini of C5a and C5adesarg. This inactivates the major chemoattractants for neutrophils that are generated when serum complement is activated. We now report the isolation of the enzyme responsible for the proteolytic cleavage of C5a. Treatment of GBS with mutanolysin, an endo-N-acetyl muramidase, released activity from GBS which destroyed the functional activity of C5a. The soluble activity was purified to homogeneity by hydroxyapatite, ion-exchange and gel-filtration chromatography. Analysis by SDS-PAGE showed that the enzyme (GBS C5a-ase) has an Mr of approx. 120,000. The GBS C5a-ase appears to be a serine esterase on the basis of its sensitivity to di-isopropyl fluorophosphate. This enzyme is distinct from the C5a-cleaving enzyme produced by group A streptococci, since the two bacterial products migrate differently on SDS-PAGE, and lack antigenic cross reactivity. This enzyme may play a role in the pathogenesis of group B streptococcal disease through its ability to rapidly inactivate the potent neutrophil agonist, C5a, at sites of infection.

Adhesins, Bacterial↗