Publications by authors named "Pezhouh M"

Aims: Widespread use of immune checkpoint inhibitors (ICIs) for treatment of advanced malignancies led to an increase in number of immune-related adverse events such as ICI gastrointestinal (GI) injury (ICIGI). The resulting immune dysregulation of the GI mucosa is believed to predispose patients to viral infections. We characterised the histopathological features of ICIGI and the frequency of viral infections such as cytomegalovirus (CMV), adenovirus, and Epstein-Barr virus (EBV).

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A variety of systemic diseases may affect the gastrointestinal (GI) tract. Since the GI tract responds to injury in limited ways, identifying these processes may be challenging, especially on small endoscopic biopsies. This article reviews the clinicopathologic features of commonly encountered systemic diseases affecting the tubular GI tract: sarcoidosis, graft vs.

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Gastrointestinal (GI) tract involvement by Langerhans cell histiocytosis (LCH) is rare and its clinicopathologic characteristics have only been described in case reports and small series. We reviewed hematoxylin and eosin and CD1a, S100, and Langerin immunohistochemical-stained slides from 47 patients with well-documented demographic and clinical findings. Our cases included 8 children and 39 adults, with a mean follow-up of 63 months.

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Article Synopsis
  • Lobular capillary hemangioma (LCH) is an uncommon condition in the GI tract, with this study analyzing its clinicopathologic features in 34 cases involving 16 men and 10 women.
  • Most cases occurred in the colorectum, with lesions often appearing as mucosal polyps, averaging 1.3 cm in size.
  • The study found that LCHs can be multifocal, have specific microscopic characteristics, and none of the patients experienced recurrence after follow-up.
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B3 thymoma is a rare malignant type of thymic epithelial neoplasm found in the anterior mediastinum. Diagnosis of thymoma from fine needle aspiration (FNA) can be challenging due to the infrequency of sampling and its morphologic overlap with other entities such as squamous cell carcinoma, lymphoma or thyroid carcinoma. We report a case of B3 thymoma mimicking poorly differentiated thyroid carcinoma.

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Programmed death ligand 1 (PD-L1) dysregulation has been implicated in chronic inflammatory diseases, but its role in regulating intestinal mucosa inflammation is still unclear. The aim of this study was to assess PD-L1 expression in the intestinal mucosa of patients with refractory inflammatory bowel disease (IBD) compared to controls. We evaluated PD-L1 expression by immunohistochemistry in colectomy specimens of patients with ulcerative colitis (UC) and Crohn disease (CD) compared to controls.

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The rate of syphilis in the United States has been increasing steadily in the past decade, but it remains an uncommon diagnosis in tissue biopsies. Most of the pathology literature on hepatic syphilis consists of older series or case reports. This study aimed to systematically characterize the histologic spectrum of hepatic syphilis in a contemporary cohort.

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Objectives: The novel coronavirus, severe acute respiratory syndrome coronavirus 2, causing coronavirus disease 2019 (COVID-19) remains a global health threat and a significant source of human morbidity and mortality. While the virus primarily induces lung injury, it also has been reported to cause hepatic sequelae.

Methods: We aimed to detect the virus in formalin-fixed tissue blocks and document the liver injury patterns in patients with COVID-19 compared with a control group.

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Hereditary pancreatitis is a rare form of recurrent acute pancreatitis that typically has an onset in early adulthood. We report a rare case of hereditary pancreatitis in an individual with a serine protease inhibitor Kazal type 1 () mutation. Histologically the pancreas showed features of chronic pancreatitis with variable fibrosis, acinar destruction, and prominent inspissated secretions within the pancreatic ducts.

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Implantable drug release platforms that offer wirelessly programmable control over pharmacokinetics have potential in advanced treatment protocols for hormone imbalances, malignant cancers, diabetic conditions, and others. We present a system with this type of functionality in which the constituent materials undergo complete bioresorption to eliminate device load from the patient after completing the final stage of the release process. Here, bioresorbable polyanhydride reservoirs store drugs in defined reservoirs without leakage until wirelessly triggered valve structures open to allow release.

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Malakoplakia is an inflammatory process related to defective macrophage response to bacterial infection. To further characterize the clinicopathologic manifestations of gastrointestinal malakoplakia, 26 cases were identified from 6 institutions. Hematoxylin and eosin-stained slides and available stains were reviewed, and pertinent clinicopathologic features analyzed.

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Colon polypectomy can require an injection of a submucosal lifting agent to fully visualize and completely remove the polyp. To the best of our knowledge, this is the largest morphologic series on the novel lifting agents Eleview and Orise. The study consisted of 1 polypectomy and 8 colon resections from 9 patients: 6 women, 3 men (mean age=64 y); Orise=6, Eleview=3; the median time interval between injection and resection=16 weeks.

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Capabilities in real-time monitoring of internal physiological processes could inform pharmacological drug-delivery schedules, surgical intervention procedures and the management of recovery and rehabilitation. Current methods rely on external imaging techniques or implantable sensors, without the ability to provide continuous information over clinically relevant timescales, and/or with requirements in surgical procedures with associated costs and risks. Here, we describe injectable classes of photonic devices, made entirely of materials that naturally resorb and undergo clearance from the body after a controlled operational lifetime, for the spectroscopic characterization of targeted tissues and biofluids.

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Objective: The aim of the study was to investigate whether inhibition of Sonic Hedgehog (SHH) pathway would prevent progression of Barrett's Esophagus (BE) to esophageal adenocarcinoma.

Background: The hedgehog signaling pathway is a leading candidate as a molecular mediator of BE and esophageal adenocarcinoma (EAC). Repurposed use of existing off-patent, safe and tolerable drugs that can inhibit hedgehog, such as itraconazole, could prevent progression of BE to EAC.

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Continuous measurements of pressure and temperature within the intracranial, intraocular, and intravascular spaces provide essential diagnostic information for the treatment of traumatic brain injury, glaucoma, and cardiovascular diseases, respectively. Optical sensors are attractive because of their inherent compatibility with magnetic resonance imaging (MRI). Existing implantable optical components use permanent, nonresorbable materials that must be surgically extracted after use.

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Pressures in the intracranial, intraocular and intravascular spaces are clinically useful for the diagnosis and management of traumatic brain injury, glaucoma and hypertension, respectively. Conventional devices for measuring these pressures require surgical extraction after a relevant operational time frame. Bioresorbable sensors, by contrast, eliminate this requirement, thereby minimizing the risk of infection, decreasing the costs of care and reducing distress and pain for the patient.

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Selective internal radiation therapy with Y-TheraSphere or Y-SIRSphere is used in the treatment of unresectable hepatic malignancies. To the best of our knowledge, this is the first Y-TheraSpheres series. BTG International Canada Inc.

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Little is known about an oncogenic signal transducer β-1,4-galactosyltransferase-V (β-1,4-GalT-V), in human colorectal cancer. Using quantitative RT-PCR, immunohistochemical staining and ELISA assays, we determined that β-1,4-GalT-V gene/protein expression is specifically increased in human colorectal cancer (CRC) tumors, compared to visibly normal tissue. Furthermore, we observed a marked increase in its enzymatic activity, and its product lactosylceramide.

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A potential role for viral infections has been implicated in inflammatory bowel disease (IBD) unresponsive to medical treatment. It is well known that Epstein-Barr virus (EBV) infection can elicit a brisk mononuclear response in the gastrointestinal tract. The aim of this study was to further evaluate the role of EBV in patients with refractory IBD and compare them with nonrefractory IBD cases.

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Background: Use of the immune checkpoint inhibitor ipilimumab is sometimes complicated by ipilimumab-associated colitis (Ipi-AC), an immune-mediated colitis that mimics inflammatory bowel disease.

Objective: We sought to characterize the histopathologic and immunophenotypic features of Ipi-AC and to directly compare these features to ulcerative colitis (UC).

Methods: This is a retrospective cohort study of 22 patients with Ipi-AC, 12 patients with treatment-naïve UC and five controls with diarrhoea but normal endoscopic findings.

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Patients with hepatocellular carcinoma (HCC) frequently have multiple anatomically distinct tumors. In these patients, multifocal HCC could represent intrahepatic metastases (IMs) of a single cancer or multicentric carcinogenesis (MC) with multiple independent neoplasms. To determine the frequency and clinical implications of these 2 possibilities, we performed histological and molecular analysis of 70 anatomically distinct HCCs from 24 patients.

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Barrett esophagus (BE) predisposes patients to the development of esophageal adenocarcinoma (EAC). However, the global definition of BE is controversial. Pathologists in Europe and the United States require intestinal metaplasia (IM) within columnar-lined mucosa (CLM) in the tubular esophagus to diagnose BE, whereas in the UK and Japan only the presence of CLM is required.

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