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Topic Review
Biography
Topic Review
Circulating Tumor Cells in Colorectal Cancer
Circulating tumor cells (CTCs) are intact cells separated from the primary tumor or metastases and released into the peripheral circulation. They were observed and discovered for the first time in 1869 in the blood of a patient with breast cancer. CTCs mainly originate from solid tumors of epithelial origin (breast, prostate, colon, and lung). CTCs are nucleated and express epithelial cell adhesion molecules (EpCAM) and/or cytokeratins (CK) in the cytoplasm without coexpressing the common leukocyte antigen CD45. It is known today that there is significant heterogeneity in cell species and surface markers, which represents a challenge in isolating all clinically relevant subpopulations of CTCs.
534
22 Nov 2022
Topic Review
Imaging in Portal Vein Thrombosis
The term portal vein thrombosis (PVT) refers to the complete or partial obstruction of blood flow in the portal vein, due to the presence of a thrombus in the vasal lumen. The underlying etiology of PVT remains unclear in up to 50% of children and adults. PVT, either primary or secondary to an underlying chronic liver disease, is the most common cause of prehepatic portal hypertension. On the one hand, primary PVT can be idiopathic, iatrogenic (neonatal umbilical vein catheterization), or related to an altered coagulation status. On the other hand, the progression of most chronic liver diseases leads to fibrosis, which increases sinusoid resistance and determines an abnormal elevation of portal venous pressure. The spontaneous development of a collateral circulation to divert the flow to the systemic circulation is the first observed anomaly, which itself contributes to PVT.
590
11 Nov 2022
Topic Review
Cancer-Associated Fibroblasts in Cholangiocarcinoma
Cholangiocarcinoma (CCA) is an aggressive neoplasia with an increasing incidence and mortality. It is characterized by a strong desmoplastic stroma surrounding cancer cells. Cancer-associated fibroblasts (CAFs) are the main cell type of CCA stroma and they have an important role in modulating cancer microenvironments. CAFs originate from multiple lines of cells and mainly consist of fibroblasts and alpha-smooth muscle actin (α-SMA) positive myofibroblast-like cells. The continuous cross-talking between CCA cells and desmoplastic stroma is permitted by CAF biochemical signals, which modulate a number of pathways. Stromal cell-derived factor-1 expression increases CAF recruitment to the tumor reactive stroma and influences apoptotic pathways. The Bcl-2 family protein enhances susceptibility to CAF apoptosis and PDGFRβ induces fibroblast migration and stimulates tumor lymphangiogenesis. Many factors related to CAFs may influence CCA prognosis.
551
10 Nov 2022
Topic Review
Human Pluripotent Stem Cell-Based Models for Hirschsprung Disease
Hirschsprung disease (HSCR) is a complex congenital disorder caused by defects in the development of the enteric nervous system (ENS). It is attributed to failures of the enteric neural crest stem cells (ENCCs) to proliferate, differentiate and/or migrate, leading to the absence of enteric neurons in the distal colon, resulting in colonic motility dysfunction. Due to the oligogenic nature of the disease, some HSCR conditions could not be phenocopied in animal models. Building the patient-based disease model using human induced pluripotent stem cells (hPSC) has opened up a new opportunity to untangle the unknowns of the disease. The expanding armamentarium of hPSC-based therapies provides needed new tools for developing cell-replacement therapy for HSCR.
468
09 Nov 2022
Topic Review
Mesenteric Ischemia
Mesenteric ischemia is a medical condition in which injury to the small intestine occurs due to not enough blood supply. It can come on suddenly, known as acute mesenteric ischemia, or gradually, known as chronic mesenteric ischemia. The acute form of the disease often presents with sudden severe abdominal pain and is associated with a high risk of death. The chronic form typically presents more gradually with abdominal pain after eating, unintentional weight loss, vomiting, and fear of eating. Risk factors for acute mesenteric ischemia include atrial fibrillation, heart failure, chronic kidney failure, being prone to forming blood clots, and previous myocardial infarction. There are four mechanisms by which poor blood flow occurs: a blood clot from elsewhere getting lodged in an artery, a new blood clot forming in an artery, a blood clot forming in the superior mesenteric vein, and insufficient blood flow due to low blood pressure or spasms of arteries. Chronic disease is a risk factor for acute disease. The best method of diagnosis is angiography, with computed tomography (CT) being used when that is not available. Treatment of acute ischemia may include stenting or medications to break down the clot provided at the site of obstruction by interventional radiology. Open surgery may also be used to remove or bypass the obstruction and may be required to remove any intestines that may have died. If not rapidly treated outcomes are often poor. Among those affected even with treatment the risk of death is 70% to 90%. In those with chronic disease bypass surgery is the treatment of choice. Those who have thrombosis of the vein may be treated with anticoagulation such as heparin and warfarin, with surgery used if they do not improve. Acute mesenteric ischemia affects about five per hundred thousand people per year in the developed world. Chronic mesenteric ischemia affects about one per hundred thousand people. Most people affected are over 60 years old. Rates are about equal in males and females of the same age. Mesenteric ischemia was first described in 1895.
237
07 Nov 2022
Topic Review
Vitamins in Inflammatory Bowel Disease
The pathogenesis of inflammatory bowel disease (IBD) highlights the role of mucosal immunology and changes in the gut microbiome triggered by genetic and environmental factors including diet regiments, as suggested by many nutritional studies. Along with medications usually used for IBD treatment, therapeutic strategies also include the supplementation of micronutrients such as vitamin D, folic acid, iron, and zinc.
563
04 Nov 2022
Topic Review
Protocols of Investigation of Neonatal Cholestasis
Neonatal cholestasis (NC) starts during the first three months of life and comprises extrahepatic and intrahepatic groups of diseases, some of which have high morbimortality rates if not timely identified and treated. Prolonged jaundice, clay-colored or acholic stools, and choluria in an infant indicate the urgent need to investigate the presence of NC, and thenceforth the differential diagnosis of extra- and intrahepatic causes of NC. The differential diagnosis of NC is a laborious process demanding the accurate exclusion of a wide range of diseases, through the skillful use and interpretation of several diagnostic tests. A wise integration of clinical-laboratory, histopathological, molecular, and genetic evaluations is imperative, employing extensive knowledge about each evaluated disease as well as the pitfalls of each diagnostic test.
691
02 Nov 2022
Topic Review
Enteric Glia and Its Modulation by Endocannabinoid System
The enteric nervous system (ENS) is a part of the autonomic nervous system that intrinsically innervates the gastrointestinal (GI) tract. Whereas enteric neurons have been deeply studied, the enteric glial cells (EGCs) have received less attention. However, these are immune-competent cells that contribute to the maintenance of the GI tract homeostasis through supporting epithelial integrity, providing neuroprotection, and influencing the GI motor function and sensation. The endogenous cannabinoid system (ECS) includes endogenous classical cannabinoids (anandamide, 2-arachidonoylglycerol), cannabinoid-like ligands (oleoylethanolamide (OEA) and palmitoylethanolamide (PEA)), enzymes involved in their metabolism (FAAH, MAGL, COX-2) and classical (CB1 and CB2) and non-classical (TRPV1, GPR55, PPAR) receptors. The ECS participates in many processes crucial for the proper functioning of the GI tract, in which the EGCs are involved.
425
01 Nov 2022
Topic Review
Antibacterial and Antiviral Properties of Tetrahydrocurcumin-Based Formulations
Special attention was given to the bactericidal effects of one of the tetrahydrocurcumin (THC)-phospholipid formulations, which has shown greater bioavailability and activity than pure THC. Similarly, quinoline derivatives and amino acid conjugates of THC have also shown antibacterial effects in the gut. Furthermore, the antiviral characteristics of curcumin (Cur) compared to those of THC are more pronounced in preventing the influenza virus.
533
01 Nov 2022
Topic Review
Quality Optimization of Small Bowel Magnetic Resonance Imaging
Magnetic resonance enterography (MRE) is one of the most highly utilised tools in the assessment of patients with small bowel Crohn’s disease (CD). As a non-invasive modality, it has both patient and procedure-related advantages over ileocolonoscopy which is the current gold standard for Crohn’s disease activity assessment. MRE relies upon high-quality images to ensure accurate disease activity assessment; however, few studies have explored the impact of image quality on the accuracy of small bowel CD activity assessment. Bowel distension and motion artifacts are two key imaging parameters that impact the quality of images obtained through MRE. Multiple strategies have been employed to both minimise the effects of motion artifacts and improve bowel distension.
411
28 Oct 2022
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