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Degenerative Diseases of the Nervous System
Published in Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw, Hankey's Clinical Neurology, 2020
James A. Mastrianni, Elizabeth A. Harris
Dystrophic neurites are found, together with loss of neocortical neurons (> 40%). Loss is widespread (hippocampus, entorhinal cortex, association areas of neocortex, and nucleus basalis of Meynert [the substantia innominata] and locus ceruleus) and predominantly involves cholinergic, noradrenergic, and dopaminergic neurons. There is loss of neuronal synapses, assessed using antibodies to synaptic proteins such as synaptophysin. The degree of synaptic loss best correlates with the severity of dementia.
Endocrine Surgery
Published in Tjun Tang, Elizabeth O'Riordan, Stewart Walsh, Cracking the Intercollegiate General Surgery FRCS Viva, 2020
A 33-year-old male who underwent a laparoscopic appendicectomy 2 weeks ago has been referred to your endocrine clinic. The histology report confirms an 18 mm carcinoid tumour in the tip of the appendix. What is a carcinoid tumour?Carcinoid tumours are of neuroendocrine origin; the term now specifically applies to tumours of the midgut origin (jejunoileal and proximal colon).They predominantly secrete serotonin; stain with chromogranin A and synaptophysin immunostains.
Viral neuro-oncogenesis: Polyomaviruses and brain tumors
Published in Avindra Nath, Joseph R. Berger, Clinical Neurovirology, 2020
Martyn K. White, Sidney E. Croul, Kamel Khalili
Histopathologically, the vast majority of medulloblastomas fall into three categories: classic, neuroblastic, and desmoplastic. They all feature densely packed cells with round to oval or carrot-shaped hyperchromatic nuclei and a high nuclear-to-cytoplasmic ratio. Homer-Wright rosettes are a frequent feature. The neuroblastic variety features columns or “Indian files” of the neoplastic cells. In the desmoplastic tumors, nodular reticulin zones (pale islands) stand out from the background of the tumor. These nodules show reduced cellularity, extracellular fibrillary material, and marked nuclear uniformity. Immunohistochemically, synaptophysin expression is characteristic of these tumors and is found prominently in nodules and neuroblastic rosettes [114]. Of the intermediate filament proteins, vimentin, nestin, and neurofilament are most characteristically expressed. Stellate GFAP positive cells are often found as well that may represent trapped astrocytes or differentiated tumor cells with an astrocytic phenotype [115]. These tumors also express both high and low affinity nerve growth factor receptors. Electron microscopy shows features consistent with embryonal neurons, including neurite-like cytoplasmic processes with microtubules and specialized adhesion plaques, dense core vesicles, and synapses [83].
Lack of bombesin receptor-activated protein homologous protein impairs hippocampal synaptic plasticity and promotes chronic unpredictable mild stress induced behavioral changes in mice
Published in Stress, 2023
Xueping Yao, Xiaoqun Qin, Hui Wang, Jiaoyun Zheng, Zhi Peng, Jie Wang, Horst Christian Weber, Rujiao Liu, Wenrui Zhang, Ji Zeng, Suhui Zuo, Hui Chen, Yang Xiang, Chi Liu, Huijun Liu, Lang Pan, Xiangping Qu
Synaptophysin is a synaptic vesicle glycoprotein present in nearly all neurons that participate in synaptic transmission. It is often used for quantification of synapses ubiquity at the synapse (Raja et al., 2019). Analysis of immunostaining of hippocampal sections showed that the percentage of the area stained by synaptophysin antibody decreased in bc004004−/− mice (Figure 6(A,B)). The expression of this protein in the hippocampal tissues analyzed by western blot is shown in Figure 6(E,F). After 21-day of CUMS both main effects of CUMS (F(1, 5) =7.5, p = .04) and genotype (F(1, 5)=13.13, p = .02) on synaptophysin expression were significant. There was interaction between genotype and CUMS treatment (F (1, 5) = 11.97, p = .02). The expression of this protein decreased in knockout mice compared with those of control mice after 21-day of CUMS.
Grape seed extract effects on hippocampal neurogenesis, synaptogenesis and dark neurons production in old mice. Can this extract improve learning and memory in aged animals?
Published in Nutritional Neuroscience, 2022
Seyed Hamidreza Rastegar-moghaddam, Maryam Bigham, Mahmoud Hosseini, Alireza Ebrahimzadeh-bideskan, Amir Mohammad Malvandi, Abbas Mohammadipour
Previous studies proved that synaptogenesis is also decreased in the aging brain [47]. New synapses are generated in the brain throughout life that generate and maintain memory and learning. In the current study, for the first time, we found that GSE improves synaptogenesis in aged mice. Our results revealed that GSE administration increases the expression of the amount of synaptophysin protein. Synaptophysin is a synaptic molecule and is a marker of synaptic density. This protein is highly expressed in the axons’ presynaptic vesicles and is the most abundant integral membrane protein constituent of synaptic vesicles in neurons [16,48]. Aging reduces synaptophysin expressions in the hippocampus [16]. Therefore, it seems that GSE can support synaptic connectivity and memory formation by preventing a decrease in hippocampal synaptophysin level. As mentioned above, GSE increases the level of BDNF, which can increase hippocampal synaptogenesis and long-term potentiation (LTP) [49]. Due to the limitations, here we investigated synaptophysin, a presynaptic marker and GSE effect on the other pre- and post-synaptic markers cannot be excluded.
Congenital Sacrococcygeal Neuroblastoma: A Report of Two Cases with Summary of Prior Published Cases
Published in Fetal and Pediatric Pathology, 2022
Soumya Dey, Arindam Ghosh, Kaushik Sil, Kalyani Saha Basu, Uttara Chatterjee
Case-2: A 6 days old baby boy presented with a swelling in the sacral region since birth. Serum AFP and hCG levels were within normal limits. MRI of lumbosacral spine showed a multilobulated mass below the distal end of spine and differential diagnosis of teratoma and terminal meningomyelocele were suggested (Fig. 3a and b). The mass was excised along with coccyx and on gross examination it was a bosselated, tan colored mass with patchy hemorrhagic and measured 5 cm. across (Fig. 3c). Microscopic examination revealed a tumor composed of small round cells with hyperchromatic nuclei and scanty cytoplasm arranged in nests. Extensive rosette formation and neuropil was identified in center of rosettes. The tumor had low MKI and minimal fibrillary stroma. On extensive sampling no heterologous elements were noted. Only remnant of coccyx was noted bearing notochordal elements in the center. On immunohistochemistry, the tumor cells were positive for synaptophysin and chromogranin (Fig. 4a–d). CD99, FLI-1, WT-1, TLE-1, desmin, myogenin, CD 117, OCT 4, LCA were negative. Based on the morphologic features and IHC findings, the diagnosis of poorly differentiated neuroblastoma was made. FISH analysis was negative for MYCN amplification. The baby was discharged on seventh post-operative day without any complications. On a fifteen months follow up, the patient is doing well without chemotherapy and urinary VMA level is normal. PET scan for metastatic workup was normal at 10 months of follow up.