A lectin histochemistry study on the development of rat microglial cells.

A lectin-histochemical study on microglial development has been performed on the rat central nervous system. Isolectin B4 from the Griffonia simplicifolia (GSA I-B4) and Ricinus communis agglutinin-120 (RCA-1) were used as labelling lectins. Our results demonstrate the existence of microglial elements in the nervous parenchyma at E18, derived from the meningeal connective tissue layer.

Resection of the buccal fat pad in the treatment of hypertrophy of the masseter muscle.

Partial resection of the buccal fat pad added to the resection of the masseter muscle clearly improves the results in hypertrophy of these muscles.

Microglial cells in the central nervous system of the rabbit and rat: cytochemical identification using two different lectins.

Microglial cells were selectively demonstrated in the central nervous system of adult rabbits and rats using lectin histochemistry. Biotinylated Ricinus communis agglutinin-120 (RCA-1) and biotinylated Griffonia simplicifolia B4 isolectin (GSA I-B4) were used as histochemical markers on sections of Bouin-fixed paraffin-embedded cerebrum and cerebellum. Results were quite similar using both lectins and both species.

Coexpression of vimentin and glial fibrillary acidic protein in astrocytes of the adult rat optic nerve.

The localization of vimentin (VIM) and glial fibrillary acidic protein (GFAP) was studied immunohistochemically in adult rat optic nerve. Consecutive Epon semithin tissue sections were immunostained respectively for VIM or GFAP. With this method, both antigens were detected in consecutive sections of the same cell.

Placebo-controlled trial of nimodipine in the treatment of acute ischemic cerebral infarction.

Nimodipine is a 1,4-dihydropyridine derivative that shows a preferential cerebrovascular activity in experimental animals. Clinical data suggest that nimodipine has a beneficial effect on the neurologic outcome of patients suffering an acute ischemic stroke. Our double-blind placebo-controlled multicenter trial was designed to assess the effects of oral nimodipine on the mortality rate and neurologic outcome of patients with an acute ischemic stroke.

Ultrastructural study on meningeal regeneration and meningo-glial relationships after cerebral stab wound in the adult rat.

Meningeal regeneration and meninges-glial relationships during the reparation of an experimental brain stab wound, are studied with the electron microscope. At 14 days after the wound, a continuous newly formed basal lamina separates both nervous and meningeal tissues. Later, the astroglial processes of regenerated glia limitans showed very infolded surfaces and numerous filaments inside of them.

Myofibroblasts in human palatal mucosa.

Myofibroblasts in human osseous palatal mucosa are described. They appear as fusiform or ramified cells, rich in homogeneous 60- to 70-Angström-thick microfilaments, rough endoplasmic reticulum cisternae, and abundant pinocytotic vesicles in relation with the plasma membrane. On the surface of these cells there are small areas covered by basal lamina.

Appearance of microglial cells in the postnatal rat retina.

The development of microglial cells in the postnatal rat retina is described using histochemical techniques for acid phosphatase and peroxidase as well as silver impregnations for microglia. On the second postnatal day, round acid phosphatase-positive macrophages appeared on the vitreal surface of retina, locating themselves close to developing blood vessels. Later, microglial precursors invaded retinal tissues, reaching the outer plexiform layer by the tenth postnatal day.

Ultrastructural study on the origin of rat microglia cells.

An ultrastructural study of the origin of microglial cells has been performed in albino rat brains taken from 17-day-old embryos up to 35-day-old rats. Invasion of the nervous parenchyma by macrophagic cells which appear in mesodermal sources is described. Although the two main microglial sources are the meningeal membranes and the vascular adventitia, pericytes may also participate in the formation of microglial cells.

The presence of oxytalan fibres in normal and regenerating rat leptomeninx: an ultrastructural demonstration.

The present ultrastructural study demonstrates the presence of oxytalan fibres in normal and regenerating leptomeninges of adult albino rats. They appear as bundles of fibrils 10-15 nm thick without transverse striations, which frequently merge with collagen microfibrils.

Nature of macrophages in rat brain. A histochemical study.

The nature of phagocytes appearing in lesions of the central nervous system is strongly debated with a tendency to assess an exclusively hematogenous origin. We studied the origin of phagocytes appearing in a stab wound in the rat brain. Histochemical stains for acid phosphatase and peroxidase, and silver impregnation techniques were used for our study.

A human plasma cell line: induction and characterization.

A stable line of IgG K producing human plasma cells was established from a myelomatous human bone marrow using conditioned media from a rapidly metabolizing lymphoblast line, RPMI 4098. Growth in RPMI 1640 (15% fetal calf serum) at 6% CO2 promoted a 62-hour doubling time with a preferred cell concentration of 1 x 10(6)/mL. Surface marker studies showed: no receptors for sheep erythrocytes, no surface immunoglobulins, variable number of cells bearing complement receptors and 83% bearing Fc receptors.

The formation of human lymphocyte colonies in semisolid cultures in response to allogeneic mixed-lymphocyte stimulation.

A technique is described for the growth of human lymphocyte colonies in semisolid culture systems in response to allogeneic lymphocyte stimulation. Colonies did not form to any major extent using autologous lymphocyte stimulation. Both one-way and two-way mixed-lymphocyte reactions were investigated.

Cell surface markers on canine lymphocytes.

Reference values for T and B lymphocytes were determined on lymphocytes from canine thymus, spleen, lymph node, bone marrow, and peripheral blood by use of erythrocyte (E) and erythrocyte-antibody-complement (EAC) rosette assays, plus a direct fluorescent technique for assay of surface immunoglobulins. Numbers of T lymphocytes, indicated by E rosette formation with human erythrocytes, ranged from a low of 1% in the thymus to 13% in the peripheral blood, whereas B-lymphocyte numbers ranged from 3% (thymus) to 41% (bone marrow) and from 6% (thymus) to 36% (bone marrow), as indicated by EAC rosette formation or presence of surface immunoglobulins respectively. Stimulation of peripheral blood lymphocytes with either phytohemagglutinin or concanavalin A increased the total number of E-rosetting cells two to threefold, whereas the number of EAC-rosetting cells decreased by half.

Markers of neoplastic transformation in epithelial cell lines derived from human carcinomas.

Density-dependent inhibition of growth, plating efficiency on confluent monolayers of 3T3 cells, and growth in agar have been measured in epithelial tumor cell lines to determine whether they have properties in common with transformed mesenchymal cells. Five lines (RT4, RT112, J82, T24, and EJ) were derived from different human bladder tumors and HT29 was from a human colon tumor. All the lines resembled transformed "fibroblasts" in the absence of density-dependent inhibition of growth and the cell-surface large external transformation-sensitive protein, and they could form colonies on 3T3 monolayers.

Metastasizing tumors from serum-supplemented and serum-free cell lines from a C57BL mouse lung tumor.

A tissue culture cell line was established from an alveologenic lung carcinoma from a C57BL/lcrf-at mouse. The cells can be maintained in a completely defined serum-free medium. Tumors derived from the tissue culture cells grown in serum-free or serum-supplemented medium give rise to lung metastases.

Midfacial fractures from vehicular accidents.

An effort is made to simplify, categorize, and outline the various forms and treatment of midfacial trauma from automotive crashes. Panfacial fractures resulting from high speed automotive accidents will continue to be a challenge to the innovative and persistent surgeon seeking the best possible results.

Nucleoid condensation and cell division in Escherichia coli MX74T2 ts52 after inhibition of protein synthesis.

The reorganization of the bacterial nucleoid of an Escherichia coli mutant, MX74T2 ts52, was studied by electron microscopy after protein synthesis inhibition by using whole mounts of cell ghosts, ultrathin-sectioning, and freeze-etching. The bacterial nucleoid showed two morphological changes after chloramphenicol addition: deoxyribonucleic acid (DNA) localization and DNA condensation. DNA localization was observed 10 min after chloramphenicol addition; the DNA appeared as a compact, solid mass.