Inhibition of microglial activity alters spinal wide dynamic range neuron discharge and reduces microglial Toll‐like receptor 4 expression in neuropathic rats

It is believed that neuropathic pain results from aberrant neuronal discharges although some evidence suggests that the activation of glia cells contributes to pain after an injury to the nervous system. This study aimed to evaluate the role of microglial activation on the hyper‐responsiveness of wide dynamic range neurons (WDR) and Toll‐like receptor 4 (TLR4) expressions in a chronic constriction injury (CCI) model of neuropathic pain in rats. Adult male Wistar rats (230 ± 30 g) underwent surgery for induction of CCI neuropathy. Six days after surgery, administration of minocycline (10, 20, and 40 mg/kg, i.p.) was initiated and continued until day 14. After administration of the last dose of minocycline or saline, a behavioral test was conducted, then animals were sacrificed and lumbar segments of the spinal cord were collected for Western blot analysis of TLR4 expression. The electrophysiological properties of WDR neurons were investigated by single unit recordings in separate groups. The findings showed that after CCI, in parallel with thermal hyperalgesia, the expression of TLR4 in the spinal cord and the evoked response of the WDR neurons to electrical, mechanical, and thermal stimulation significantly increased. Post‐injury administration of minocycline effectively decreased thermal hyperalgesia, TLR4 expression, and hyper‐responsiveness of WDR neurons in CCI rats. The results of this study indicate that post‐injury, repeated administration of minocycline attenuated neuropathic pain by suppressing microglia activation and reducing WDR neuron hyper‐responsiveness. This study confirms that post‐injury modulation of microglial activity is a new strategy for treating neuropathic pain.     

Reserpine-induced altered neuro-behavioral,biochemical and histopathological assessments prevent by enhanced antioxidant defence system of thymoquinone in mice

Metabolic Brain Disease - Thymoquinone (Tq), an active compound of Nigella sativa, has been known for its anti-inflammatory, antioxidant, and neuroprotective characteristics. The present study is...     

Potential role of Nigella sativa supplementation with physical activity in prophylaxis and treatment of COVID-19: a contemporary review

Sport Sciences for Health - The widespread prevalence and mortality of coronavirus diseases-2019 (COVID-19) lead many researchers to study the SARS-CoV-s2 infection to find a treatment for this...     

Endoscopic ultrasound‐guided fine‐needle aspiration diagnosis of large cell neuroendocrine carcinoma of the gallbladder and common bile duct: Report of a case

Endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) allows a reliable and accurate diagnosis of neoplasms of the gallbladder and bile ducts. We report the cytopathologic findings of a case of large cell neuroendocrine carcinoma (LCNEC) of the gallbladder and extrahepatic bile ducts in a 67‐year‐old woman who presented with progressive abdominal pain and jaundice. EUS‐FNA of the mass involving the common bile duct and of a porta hepatis lymph node showed abundant cellularity with tumor cells arranged singly and occasionally in tight and loose clusters and rosette‐like structures in a background showing extensive necrotic debris. The tumor cells were predominantly plasmacytoid, showed a moderate amount of focally vacuolated cytoplasm and large round to oval hyperchromatic nuclei with prominent nucleoli, numerous mitoses, and apoptotic bodies. The differential diagnosis included poorly differentiated adenocarcinoma, lymphoma, melanoma, and poorly differentiated neuroendocrine carcinoma (NEC), large cell type. The tumor cells were strongly and diffusely positive for cytokeratin AE1/AE3, CD56, synaptophysin, and chromogranin and showed a very high proliferative fraction on Ki67 staining, supporting the diagnosis of a high‐grade NEC. Due to the large size of the neoplastic cells, moderate amounts of cytoplasm and prominent nucleoli, a diagnosis of LCNEC was made on the EUS‐FNA sample. Despite the prompt institution of chemotherapy, the patient died shortly thereafter and the diagnosis was confirmed at autopsy. This is to our knowledge the first case of LCNEC of the gallbladder and bile ducts diagnosed by EUS‐FNA. Diagn. Cytopathol. 2013;41:1091–1095. © 2012 Wiley Periodicals, Inc.     

Large platelet aggregates in endoscopic ultrasound‐guided fine‐needle aspiration of the pancreas and peripancreatic region: A clue for the diagnosis of intrapancreatic or accessory spleen

Intrapancreatic and intraabdominal accessory spleens (IPIASs) are rarely encountered in endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) biopsies. However, as incidentally discovered IPIAS can mimic a benign or malignant pancreatic neoplasm on imaging studies, a definitive diagnosis made by EUS‐FNA can avert an unnecessary surgical intervention or additional radiologic follow‐up. We report five cases of intrapancreatic splenules and one case of accessory spleen (AS) in which a definitive diagnosis was made on EUS‐FNA. Previously recognized FNA cytomorphologic features of splenic tissue, including ASs and splenosis, are endothelial cells and polymorphous lymphocytes admixed with neutrophils, eosinophils, plasma cells, histiocytes, and lymphoglandular bodies. We describe the additional finding of abundant large platelet aggregates as another distinguishing feature of splenic tissue on FNA. In all six cases, large platelet aggregates were identified along with polymorphous lymphoid cells, lymphoglandular bodies, loose aggregates of endothelial cells and scattered or aggregated bland spindle cells. A review of 10 consecutive cases of EUS‐FNA‐sampled benign intraabdominal lymph nodes showed that the presence of large platelet aggregates, three‐dimensional aggregates of lymphoid cells and of bland slender spindle cells and the absence of follicular germinal cell components (tingible body macrophages and lymphohistiocytic aggregates) are useful in differentiating IPIASs from reactive lymph nodes. Immunoperoxidase stains were useful to confirm a suspected IPIASs by showing CD31‐positive acellular flocculent material, consistent with large platelet aggregates and a rich CD8‐positive endothelial cell network between CD45‐positive lymphoid cells and CD68‐positive histiocytes in all six cases. Diagn. Cytopathol. 2013;41:661–672. © 2013 Wiley Periodicals, Inc.