Increased Mast Cell Counts and Degranulation in Microscopic Colitis

Objectives: Microscopic colitis (MC) is characterized by chronic diarrhea, normal colonoscopy findings, and mucosal inflammation in colonic biopsies and can be classified as collagenous colitis (CC) or lymphocytic colitis (LC). However, the pathogenesis of MC is largely unknown. In this study, we aimed to study mast cell counts and activation in MC. Methods: We investigated 64 biopsy samples from the surgical pathology database of Indiana University Health, which met the diagnostic criteria for CC or LC along with 20 control samples collected from 2014 to 2015. The specimens were used for the quantification of mast cells by examining the presence of intracellular and extracellular tryptase by immunohistochemistry. Results: In the lamina propria, the mast cell count was higher in both CC and LC groups than the control (mean highest count, 39/high-power field (HPF) vs. 30/HPF vs. 23/HPF; P < 0.01). Extracellular tryptase was present in 10% of control subjects as compared to 41% of CC (P < 0.01). Extracellular tryptase was present in 10% of control subjects as compared to 41% of CC (P < 0.01). Extracellular tryptase was present in 10% of control subjects as compared to 41% of CC (. Conclusions: The increased mast cell count and degranulation are identified in MC, suggesting that mast cell activation might be involved in the pathogenesis of MC

Multivisceral Transplant is a Viable Treatment Option for Patients with Nonresectable Intra-abdominal Fibromatosis

Background Intra-abdominal fibromatosis often involves the mesentery root which is non-resectable by conventional surgery. Multivisceral transplant (MVT), as a potential cure to non-resectable fibromatosis, has rarely been reported and the prognosis is unknown. Methods Six patients who underwent MVT for intra-abdominal fibromatosis were reviewed. Clinicopathological features, immunohistochemistry for β-catenin, p53, and Ki67, and outcomes were evaluated. Appropriate data for comparative analysis were obtained from a cohort of 24 patients who underwent conventional resection for intra-abdominal fibromatosis. Results Among six MVT patients, four had familial adenomatous polyposis (FAP). Two patients had an initial intestinal transplantation, three had multiple prior surgeries, and two had adjuvant therapy. One patient died of hemorrhagic stroke shortly after MVT, and five patients (83%) survived with a median follow-up of 64 months. The 1-year and 5-year survival rates were 67% for all five patients. Two patients had recurrences after MVT and one of them had FAP. In comparison, six of 24 patients who underwent conventional surgery had FAP; six (25%) had recurrences and three had FAP. For FAP patients; the mean recurrence time was 13 months for MVT versus 6 months for conventional surgery. Ki67 proliferative index, β-catenin, and p53 expression did not significantly correlate to recurrence. Conclusions Multivisceral transplant (MVT) is a viable option for patients who have non-resectable intra-abdominal fibromatosis with promising surviving rates, although recurrence still occurs. Surgical margin, Ki67 proliferative index, β-catenin, and p53 expression are not predicative for recurrence of fibromatosis

Mucinous intrahepatic cholangiocarcinoma: a distinct variant

Mucinous variant of intrahepatic cholangiocarcinoma (iCC) is rare, and its clinicopathological features and prognosis are far less clear. Six patients who had iCCs with more than 50% of mucinous component and 79 conventional iCCs were included in the study. The mean size of mucinous and conventional iCCs was 6.2 cm and 6.0 cm, respectively. The majority of patients (83%) with mucinous iCC presented at T3 stage or above, compared to 28% of the conventional group (p < 0.01). Three patients with mucinous iCC (50%) died within 1 year. The average survival time of patients with mucinous iCCs was significantly reduced compared to that of conventional group (9 months vs 2 years; P < .001). Immunohistochemistry was performed on 6 mucinous and 12 conventional iCCs with matched age, sex and stage, which revealed positive immunoreactivity in MUC1 (83% vs 58%), MUC2 (33% vs 17%), MUC5AC (100% vs 42%), MUC6 (50% vs 0), CK7 (83% vs 83%), CK20 (0 vs 17%), and CDX2 (17% vs 0) in mucinous and conventional iCCs, respectively. Molecular studies showed one mucinous iCC with KRAS G12C mutation and no BRAF or IDH1/2 mutations. Mucinous iCC is a unique variant that constitutes 7.2% of iCCs. It is more immunoreactive for MUC1, MUC2, MUC5AC and MUC6. Unlike adenocarcinomas of colorectal primary, mucinous iCCs are often CK7+/CK20-/CDX2- and microsatellite stable. Patients with mucinous iCC likely present at advanced stage upon diagnosis with shorter survival time compared to the conventional counterparts

The AAA+ ATPase Thorase Regulates AMPA Receptor-Dependent Synaptic Plasticity and Behavior

SummaryThe synaptic insertion or removal of AMPA receptors (AMPAR) plays critical roles in the regulation of synaptic activity reflected in the expression of long-term potentiation (LTP) and long-term depression (LTD). The cellular events underlying this important process in learning and memory are still being revealed. Here we describe and characterize the AAA+ ATPase Thorase, which regulates the expression of surface AMPAR. In an ATPase-dependent manner Thorase mediates the internalization of AMPAR by disassembling the AMPAR-GRIP1 complex. Following genetic deletion of Thorase, the internalization of AMPAR is substantially reduced, leading to increased amplitudes of miniature excitatory postsynaptic currents, enhancement of LTP, and elimination of LTD. These molecular events are expressed as deficits in learning and memory in Thorase null mice. This study identifies an AAA+ ATPase that plays a critical role in regulating the surface expression of AMPAR and thereby regulates synaptic plasticity and learning and memory

Pax8 as a useful adjunct marker to differentiate pancreatic serous cystadenoma from clear cell renal cell carcinoma in both cytologic and surgical specimens

Abstract Background Histomorphological differentiation between pancreatic serous cystadenoma (SCA) and clear cell renal cell carcinoma (RCC) can be challenging. We aimed to study Paired box 8 protein (Pax8) expression profile in cytologic and surgical specimens with pancreatic SCA to assess its utility as a differentiating marker from clear cell RCC. Methods We characterized Pax8 immunohistochemistry in 33 patients with pancreatic SCA (23 surgical resections and 10 cytology specimens). Nine cytology specimens from metastatic clear cell RCC involving pancreas were used as control tissue. Electronic medical records were reviewed to retrieve clinical information. Results All 10 pancreatic SCA cytology specimens, and 16 of 23 pancreatic SCA surgical resections showed absent Pax8 immunostaining, while the remaining 7 surgical resection specimens showed 1%-2% immunoreactivities. Islet and lymphoid cells adjacent to the pancreatic SCA expressed Pax8. In contrast, the proportion of Pax8 immunoreactivity ranged from 50 to 90% (average of 76%) in nine cases of metastatic clear cell RCC involving pancreas. Using a 5% immunoreactivity cutoff, all cases of pancreatic SCA are interpreted as negative for Pax8 immunostains while all cases of metastatic clear cell RCC involving pancreas are interpreted as positive for Pax8 immunostains. Conclusions These results suggest that Pax8 immunohistochemistry staining can be a useful adjunct marker to differentiate pancreatic SCA from clear cell RCC in clinical practice. To the best of our knowledge, this is the first large-scale study of Pax8 immunostaining on surgical and cytology specimens with pancreatic SCA

Neonatal stroke in mice causes long-term changes in neuronal notch-2 expression that may contribute to prolonged injury

Background and Purpose: Notch receptors (1–4) are membrane proteins that, on ligand stilumation, release their cytoplasmic domains to serve as transcription factors. Notch-2 promotes proliferation both during development and cancer, but its role in response to ischemic injury is less well understood. The purpose of this study was to understand whether Notch-2 is induced after neonatal stroke and to investigate its functional relevance.Methods: P12 CD1 mice were subjected to permanent unilateral (right-sided) double ligation of the common carotid artery.Results: Neonatal ischemia induces a progressive brain injury with prolonged apoptosis and Notch-2 up-regulation. Notch-2 expression was induced shortly after injury in hippocampal areas with elevated c-fos activation and increased cell death. Long-term induction of Notch-2 also occurred in CA1 and CA3 in and around areas of cell death, and had a distinct pattern of expression as compared to Notch-1. In vitro oxygen glucose deprivation treatment showed a similar increase in Notch-2 in apoptotic cells. In vitro gain of function experiments, using an active form of Notch-2, show that Notch-2 induction is neurotoxic to a comparable extent as oxygen glucose deprivation treatment.Conclusions: These results suggest that Notch-2 up-regulation after neonatal ischemia is detrimental to neuronal survival

Botch Is a γ-Glutamyl Cyclotransferase that Deglycinates and Antagonizes Notch

Botch promotes embryonic neurogenesis by inhibiting the initial S1 furin-like cleavage step of Notch maturation. The biochemical process by which Botch inhibits Notch maturation is not known. Here, we show that Botch has γ-glutamyl cyclotransferase (GGCT) activity that deglycinates Notch, which prevents the S1 furin-like cleavage. Moreover, Notch is monoglycinated on the γ-glutamyl carbon of glutamate 1,669. The deglycinase activity of Botch is required for inhibition of Notch signaling both in vitro and in vivo. When the γ-glutamyl-glycine at position 1,669 of Notch is degylcinated, it is replaced by 5-oxy-proline. These results reveal that Botch regulates Notch signaling through deglycination and identify a posttranslational modification of Notch that plays an important role in neurogenesis

Dynamically Reversible Interconversion of Molecular Catalysts for Efficient Electrooxidation of Propylene into Propylene Glycol

For the electrooxidation of propylene into 1,2-propylene glycol (PG), the process involves two key steps of the generation of *OH and the transfer of *OH to the CC bond in propylene. The strong *OH binding energy (EB(*OH)) favors the dissociation of H2O into *OH, whereas the transfer of *OH to propylene will be impeded. The scaling relationship of the EB(*OH) plays a key role in affecting the catalytic performance toward propylene electrooxidation. Herein, we adopt an immobilized Ag pyrazole molecular catalyst (denoted as AgPz) as the electrocatalyst. The pyrrolic N–H in AgPz could undergo deprotonation to form pyrrolic N (denoted as AgPz-Hvac), which can be protonated reversibly. During propylene electrooxidation, the strong EB(*OH) on AgPz favors the dissociation of H2O into *OH. Subsequently, the AgPz transforms into AgPz-Hvac that possesses weak EB(*OH), benefiting to the further combination of *OH and propylene. The dynamically reversible interconversion between AgPz and AgPz-Hvac accompanied by changeable EB(*OH) breaks the scaling relationship, thus greatly lowering the reaction barrier. At 2.0 V versus Ag/AgCl electrode, AgPz achieves a remarkable yield rate of 288.9 mmolPG gcat–1 h–1, which is more than one order of magnitude higher than the highest value ever reported