The distribution of the 5 alpha-reductase, the enzyme which converts testosterone into its 'active' metabolite dihydrotestosterone (DHT), has been studied in neurons, astrocytes and oligodendrocytes isolated from the brain of male rats by density gradient ultracentrifugation and in neurons and glial cells grown in cultures. Purity of cellular preparations was examined by electron and light microscopy. Purified neurons, astrocytes and oligodendrocytes, obtained from the brain of adult male rats, are all able to form DHT from testosterone and consequently possess a 5 alpha-reductase activity.
View Article and Find Full Text PDFThe 5 alpha-reductase, the enzyme which converts testosterone into dihydrotestosterone (DHT), is present in several CNS structures of the rat. Recent reports from this laboratory indicate that the subcortical white matter and the myelin possess a 5 alpha-reductase activity several times higher than that present in the cerebral cortex. Moreover, previous ontogenetic observations indicate that in all cerebral tissues examined (including the myelin) the 5 alpha-reductase has a higher activity in immature animals.
View Article and Find Full Text PDFPrevious reports from this laboratory indicate that the 5 alpha-reductase, the enzyme which converts testosterone into its "active" metabolite 5 alpha-androstan-17 beta-ol-3-one (dihydrotestosterone, DHT) is highly concentrated in the white matter structures of the CNS, which are mainly composed of myelinated fibers. No studies have been performed up to now, in order to evaluate the possible presence of the 5 alpha-reductase activity in peripheral myelinated nerves. To this purpose the 5 alpha-reductase activity has been evaluated in the sciatic nerve of the rat and compared to that present in the cerebral cortex and in the subcortical white matter, a central structure mainly composed of myelinated fibers.
View Article and Find Full Text PDFThe visual evoked potentials by half-field pattern reversal method were recorded in 12 hemianopic patients. The VEP amplitudes ipsilaterally to the occipital lesion were more important after periorbital acupuncture.
View Article and Find Full Text PDFWe describe the immunohistochemical distribution of components of the extracellular matrix of the chick lymphoid system. In the thymus, basement membranes of epithelial cells bordering the lobules were intensely stained by laminin antibodies; fibronectin antibodies labeled the capsule and the septal matrix, and similar reactivity was seen with tropoelastin and gp 115 antibodies. No positivity was detected with any of the antibodies within the cortical parenchymal cells.
View Article and Find Full Text PDFThe 5 alpha-reductase, the enzyme which converts testosterone into its major "active" metabolite (dihydrotestosterone, DHT), has been found to be present in high concentration in brain structures particularly rich of myelin (white matter structures), as well as in myelin membranes. Previous ontogenetic observations seem to indicate that, during the process of myelinogenesis, the enzyme might be synthesized in the oligodendrocytes, and subsequently incorporated into the myelin membranes. It is well established that postnatal malnutrition produces a decreased formation of myelin, when starvation is performed from birth until to the 2nd or 3rd week of life; on the contrary food deprivation does not produce any significant effect on myelin accumulation when performed after the 14th day of life.
View Article and Find Full Text PDFIntermediate lymphocytic lymphoma has been operationally included among low-grade lymphomas, but few clinical data appeared to support definitely such an inclusion. The clinicopathologic features of 13 out of 14 cases of intermediate lymphocytic lymphoma either encompassing diffuse or mantle-zone pattern variants (ILL or MZL, respectively), diagnosed by conventional histology according to established criteria, are reported. Frozen section immunophenotypic analysis was also performed in 10 cases and enzyme studies were done in five.
View Article and Find Full Text PDFIn the central nervous system of the rat, the 5 alpha-reductase, the enzyme which converts testosterone into dihydrotestosterone, appears to be concentrated in the white matter and in particular to be associated with myelin. In order to verify whether a temporal correlation might exist between the formation of myelin membranes and the variations of the 5 alpha-reductase activity observed in the brain, the enzymatic activity was studied in the cerebral cortex and in the hypothalamus of male rat in the age range of 3-60 days, in myelin purified from animals of 15-60 days of life and in oligodendrocytes (i.e.
View Article and Find Full Text PDFPrevious results have shown that human lymphocyte subpopulations are heterogeneous as to Leu-8 expression. In the present study, we performed a heretofore unreported immunohistologic analysis and flow cytometric double labeling investigation focused on Leu-8+ and Leu-8- human B cells, with special reference to their expression of other B cell lineage antigens (Leu-14, B1, OKB7 or B2, OKB2, BA-1, BA-2, IgD, and IgM) or of a functional marker of cell proliferation (Ki-67). Immunohistologic analysis was performed on frozen sections of nine normal or reactive lymph node and tonsil biopsy specimens tested with either single or paired antibodies, the latter procedure (double labeling) being directed at revealing positively subtracted Leu-8+ or Leu-8- cells expressing a given marker depending on the antibody staining sequence used.
View Article and Find Full Text PDFPrevious results obtained in this laboratory indicate that in the rat brain the 5 alpha-reductase, the enzymatic activity involved in metabolizing testosterone into 5 alpha-androstan-17 beta-ol-3-one (dihydrotestosterone), is particularly concentrated in the white matter. In the present experiments, this enzymatic activity was studied in the following white matter structures, which were microdissected using the punch technique of Palkovits: anterior commissure (CA), fornix (FX), habenulo-interpeduncular tract (HP), corpus callosum (CC), stria medullaris (SM), optic chiasm (CO), fimbria of the hippocampus (FI), cerebral peduncle (PC), pontine fibers (FP), cerebellar medulla (CMD) and corticospinal tract (TCS). Moreover brain myelin was isolated and purified by sucrose density gradient ultracentrifugation.
View Article and Find Full Text PDFA family lineage is reported in whom several subjects, all of them females, suffered from SDAT. The existence of a subgroup of inherited dementias affecting only females is discussed.
View Article and Find Full Text PDFSalivary gland lymph node involvement is rare in patients at risk for AIDS. Intraparotid and perisubmaxillary gland lymph node biopsies from 2 intravenous drug abusers serologically positive for human immunodeficiency virus (HIV) affected by persistent generalized lymphadenopathy (PGL) were also analyzed immunohistologically. We found hypervascular reactive lymphoid hyperplasia with prevalence of suppressor T-cells within follicular centers often lacking surface IgD-positive mantle zone cells and showing disruption of the network of dendritic reticulum cells revealed with DRC-1 and anti-S-100 protein antibodies.
View Article and Find Full Text PDFFollicular dendritic reticulum cells (DRCs) are known to be normally present in primary follicles and both follicular centres and mantle zones of secondary follicles of peripheral lymphoid tissue. Involved frozen biopsy tissue specimens from eight cases of intermediate lymphocytic lymphoma/mantle zone lymphoma (ILL/MZL); eight cases of follicular centre cell lymphomas (FCCL) of the centroblastic/centrocytic type; and seven cases of well-differentiated lymphocytic lymphoma (WDLL) consistent with chronic lymphocytic leukaemia (CLL) were analysed immunohistologically with R4/23 (DRC-1) monoclonal antibody reactive with 'bystander' DRCs. As opposed to FCCL and most WDLL/CLL cases, the DRCs consistently formed a loose, ill-defined meshwork with a radiating or blurred outline in all MZL cases and one ILL.
View Article and Find Full Text PDFUsing in situ immunohistological analysis, expression of Leu-8 and its correlation with other B-cell markers were investigated in 21 selected lymphomas of different categories, each one expressing its own typical immunophenotype. These categories included eight follicular centroblastic/centrocytic (CB/CC) lymphomas, eight intermediately differentiated lymphocytic lymphomas (ILL)/mantle zone lymphomas (MZL), and five lymphocytic lymphomas (LL) associated with chronic lymphocytic leukaemia (CLL). Four reactive lymph nodes and three tonsils were also studied using double immunolabelling procedures.
View Article and Find Full Text PDFThe distribution of S-100 protein was investigated in normal or reactive lymphoid organs from adult mice, rats and humans by the avidin-biotin complex ABC) immunoperoxidase method. In mouse lymph nodes and spleen the protein appeared to be confined to the "tingible-body macrophages" and occasionally in sinus histiocytes in the lymph nodes. No immunoreaction product was detected in the other cell types present inside or outside the follicles.
View Article and Find Full Text PDFA comparative immunohistologic study of the cell density and distribution pattern of follicular dendritic reticulum cells (DRCs) within their follicular microenvironments (germinal centers and mantle zones) was performed by immunoperoxidase technique with a selected panel of antibodies either operationally specific for DRCs (DRC-1) or reported as having additional immunoreactivity with DRCs (antibodies to B- and T-cells, leukocytes, monocytes/macrophages, desmosomal components, and S-100 protein). Twenty-five biopsy specimens, including reactive lymph nodes and tonsils as well as normal spleen tissue, were analyzed. Serial frozen sections were tested either with single antibodies or paired monoclonal reagents in double-labeling procedures.
View Article and Find Full Text PDFThe phenotype of follicular dendritic reticulum cells (DRC) was analyzed with monoclonal antibodies (DRC-1, OKB7, BA-2, Leu-M3, and antidesmoplakin 1 and 2) in 28 frozen biopsy specimens of both morphologically and phenotypically analyzed B-cell lymphomas and 21 normal or reactive controls. The former included 15 follicular center cell lymphomas (FCCL), four intermediately differentiated lymphocytic lymphomas (ILL), four mantle zone lymphomas (MZL), and five well-differentiated lymphocytic lymphomas (WDLL). In controls, DRC-1+ and OKB7+ DRC were localized in both follicular centers (FC) and mantle zones (MZ), but BA-2+ and Leu-M3+ DRC were confined to FC only.
View Article and Find Full Text PDFJ Immunol Methods
December 1987
A rapid immunohistologic method is described to analyze the possible cell origin of a given neoplasm during surgery by using selected examples of monoclonal and polyclonal antibodies (anti-cytokeratins, anti-vimentin, anti-leukocyte common antigen, and anti-keratin). This rapid (26-28 min) procedure, consisting of a two-step immunoperoxidase method, did not differ in terms of intensity and specificity of the immunoreaction from the control procedure for which conventional longer times of incubation and washing were used. The results demonstrate the feasibility and effectiveness of the procedure.
View Article and Find Full Text PDFFifty-eight paraffin-embedded lymph node biopsies from patients with Hodgkin's disease (36 nodular sclerosis, 14 mixed cellularity, five lymphocyte depletion, and three lymphocyte predominance) were immunostained with a panel of monoclonal (anti-Leu-M1, antileukocyte common antigen) and polyclonal (to lysozyme, alpha 1-antitrypsin, alpha 1-antichymotrypsin, and S-100 protein) antibodies by using the avidin-biotin immunoperoxidase technique. Both the immunostaining features of the Reed-Sternberg (R-S) cells and their variants, and the numbers of immunostained accompanying cells morphologically corresponding to macrophage-histiocytes (M-H) and to interdigitating reticulum cells (IRC) were analyzed. Variable numbers of R-S cells and their variants were positive for Leu-M1 in 83% of the cases, for alpha 1-antitrypsin in 40%, for alpha 1-antichymotrypsin in 30%, and for leukocyte common antigen in 3.
View Article and Find Full Text PDFThe presence and distribution of S-100 protein were studied in a case of ovarian teratoma using avidin-biotin complex immunoperoxidase method. S-100 immunoreactivity within the well-differentiated teratomatous tissues appeared to mirror that of their normally developed human counterparts, although we could unexpectedly detect S-100 immunoreactivity in bone osteoblasts and osteocytes, and in tooth germ odontoblasts. Choroid plexus-like formations present in the teratoma were also positive.
View Article and Find Full Text PDFFrozen sections of chick tissues were exposed to affinity-purified monoclonal antibodies raised against chick gp 115 and to affinity-purified antibodies raised against chick tropoelastin to study the distribution pattern of the corresponding antigens by the avidin-biotin immunoperoxidase technique. Laminin and fibronectin antibodies were used for comparison. Gp 115 and tropoelastin antibodies localized to the same structure in several of the tissues examined.
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