Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ultrastructural study of neuroblastoma group tumors including 7 neuroblastomas, 4 ganglioneuroblastomas, and 2 ganglioneuromas was performed by using both TEM and SEM. Tumor cells showed a wide variation comparable to the developmental stages of nerve cells and were classified into four types according to the neuritic process projections; namely apolar, monopolar, bipolar, and multipolar. Neuroblastoma was composed of small cells of apolar, monopolar, and bipolar types with few multipolar cells. Tumor cells ganglioneuroblastoma and ganglioneuroma were multipolar type. SEM observation demonstrated characteristic varicosities in the elongated neuritis processes, and by TEM examination the dilated portions of these varicosities revealed disruption or disappearance of parallel runnings of the microtubules and microfilaments. TEM examination demonstrated presence of Schwann cells in ganglioneuroblastoma and ganglioneuroma, and satellite cells and perineurial cells in ganglioneuroma. The hitherto undescribed cells with caveolar structure which are thought to be a precursor of these stromal elements were disclosed in ganglioneuroblastoma. In order to evaluate the maturation and prognosis of tumors of this group, stromal differentiation seems to be equally important as ganglionic differentiation because both stromal elements and tumor cells have a common origin of neural crest.
 ...
PMID:Transmission and scanning electron microscopic studies on the tumors of neuroblastoma group. 628 64

The mechanisms of activation and termination of autoimmune responses are poorly understood. We have studied the sites and mode of activation and elimination of T cells in actively induced experimental autoimmune neuritis (EAN) and in adoptively transferred by P2-specific T cells (AT-EAN). The bromodeoxyuridine (BrdU) technique was employed to detect in situ proliferating cells in spleen and sciatic nerve. We assessed the nuclear morphology of infiltrating T cells using morphological criteria of apoptotic cell death. Apoptosis of lymphoid cells was also investigated using molecular labeling techniques. In AT-EAN, the number of BrdU positive cells in splenic germinal centers peaked at day 2 after cell transfer [554 +/- 267] (mean +/- SEM per mm2, controls 98 +/- 35), 1 day before disease onset, and declined thereafter. BrdU incorporation in spleens from animals with active EAN peaked at day 11, around disease onset, but reached lower total values (165 +/- 29 per mm2). In neither model did we observe a significant proportion of BrdU-positive T cells in the peripheral nervous system. However, T cells exhibiting morphological signs of apoptosis were detected in the sciatic nerve immediately after disease onset. The number of these cells was highest on day 7 in AT-EAN (6.6 +/- 3.2 per mm2) and on day 17 in active EAN (11.2 +/- 2.2 per mm2) corresponding to the maximum of T cell infiltration in both animal models. T cell activation occurs systematically and not just in the autoimmune lesion. Infiltrating T cells are eliminated by apoptosis in situ, terminating the inflammatory process. Further insight into these mechanisms may help to develop new therapeutic strategies for autoimmune disorders of the peripheral nervous system.
 ...
PMID:In situ demonstration of T cell activation and elimination in the peripheral nervous system during experimental autoimmune neuritis in the Lewis rat. 892 12

The effect of systemic complement depletion by cobra venom factor (CVF) was evaluated in adoptive transfer experimental allergic neuritis (AT-EAN). Spleen cells of rats immunized with a neuritogenic peptide SP26 were injected into naive rats. On days 3 and 6 after cell transfer AT-EAN rats were treated with CVF or saline intraperitoneally. AT-EAN rats treated with CVF had significantly lower scores for histological inflammation (0.25 +/- 0.25 vs 1.9 +/- 0.4, mean +/- SEM, P < 0.03) and demyelination (0.13 +/- 0.13 vs 1.6 +/- 1.4, P < 0.02) than saline-treated AT-EAN rats. Immunocytochemistry of lumbosacral nerve roots showed significantly less ED1-positive macrophages (0.5 +/- 0.3 vs 1.6 +/- 0.6, P < 0.04) and CD11bc-positive (expressing complement receptor 3 or CR3) inflammatory cells (0.6 +/- 0.4 vs 1.7 +/- 0.5, P < 0.03). Our data suggest that complement plays a crucial role in inflammatory demyelination since systemic complement depletion significantly reduces recruitment of macrophages into the nerve and subsequent macrophage-mediated demyelination.
 ...
PMID:Systemic complement depletion reduces inflammation and demyelination in adoptive transfer experimental allergic neuritis. 954 96

Partial median-nerve injury high in the upper extremity, resulting from brachial plexus neuritis or trauma, can affect the pronator teres muscle and result in the inability to pronate the forearm. A nerve transfer from an ulnar nerve-innervated branch to the flexor carpi ulnaris (FCU) muscle to the branch to the pronator teres (PT) is an attractive option in this clinical scenario. This study, a histomorphometric analysis of nine cadaver specimens harvested at the proposed FCU branch to PT branch transfer site, demonstrates sufficient similarities between the two branches in total number of nerve fibers (371.6 with SEM 35.1, and 361.9 with SEM 47.1; p = 0.87) and nerve cross-sectional area (122,181 microm2 with SEM 14,546 microm2, and 142,492 microm2 with SEM 19,633 microm2; p = 0.42), to predict a functional transfer result. In addition, clinical application of this transfer resulted in functional pronation strength of M4+.
 ...
PMID:Transfer of flexor carpi ulnaris branch of the ulnar nerve to the pronator teres nerve: histomorphometric analysis. 1044 17