Aina Venkatasamy

Surgical management of a De Garengeot’s hernia using a biologic mesh: A case report and review of literature

Highlights • The De Garengeot hernia is a rare form of femoral hernia, containing the appendix, first described by french surgeon René Jacques Croissant de Garengeot (1688–1759).• There is no consensus for the surgical approach in case of a De Garengeot hernia.• In this case, we chose to perform an inguinal approach associated with a laparoscopic procedure.• We chose to repair the femoral hernia with a biological mesh to prevent infections.

A redox ruthenium compound directly targets PHD2 and inhibits the HIF1 pathway to reduce tumor angiogenesis independently of p53

Targeting specific tumor metabolic needs represents an actively investigated therapeutic strategy to bypass tumor resistance mechanisms. In this study, we describe an original approach to impact the cancer metabolism by exploiting the redox properties of a ruthenium organometallic compound. This organometallic complex induced p53-independent cytotoxicity and reduced size and vascularization of patients-derived tumor explants that are resistant to platinum drugs. At the molecular level, the ruthenium complex altered redox enzyme activities and the intracellular redox state by increasing the NAD+/NADH ratio and ROS levels. Pathway analysis pointed to HIF-1 as a top deregulated metabolite pathway. Unlike cisplatin, treatment with the ruthenium complex decreased HIF1A protein levels and expression of HIF1A target genes. The rapid downregulation of HIF1A protein levels involved a direct interaction of the ruthenium compound with the redox enzyme PHD2, a HIF1A master regulator. HIF1A inhibition led to decreased angiogenesis in patient-derived xenografted using fragments of primary human colon tumors. Altogether, our results show that a ruthenium compound impacts metabolic pathways acting as anticancer agents in colon cancer via an original mechanism of action that affects redox enzymes differently than platinum-based drugs.

The hyperdense crescent sign

Wenjing Pang, Anne Karol, Quentin Minault, Francis Veillon, and Aina Venkatasamy 2,3 Shanghai Ninth People’s Hospital, Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China Lab. Stress Response and Innovative Therapies, Inserm U1113, Strasbourg University, Strasbourg, France Service de Radiologie 1, Hôpital de Hautepierre, Hôpitaux Universitaires de Strasbourg, 1 avenue Molière, 67098 StrasbourgCedex, France

White liver sign

The white liver sign refers to a spontaneously hyperdense appearance of the liver on non-injected abdominal CT [1]. The accumulation of substances in the liver, such as iron in hemochromatosis, copper in Wilson’s disease, or drugs such as amiodarone, can result in diffusely increased attenuation of the liver parenchyma [2] (Fig. 1), as compared with the spleen and surrounding tissue. In the presence of a white liver sign, the attenuation value of the liver is about 110 HU, while the normal mean liver attenuation is approximately 55 HU (Fig. 2) [2–5].

Tree-in-bud sign

The tree-in-bud pattern represents bronchiolar luminal impaction with mucus, pus or fluid, which demarcates the normally invisible branching course of the distal peripheral pathways, thus resembling a tree branch studded with buds on High-Resolution CT of the lungs (Figs. 1, 2) [1]. This sign corresponds to small (2–4 mm) and peripheral (close to the pleural surface) well-defined small nodules of soft-tissue attenuation which are connected to linear branching opacities with more than one contiguous branching site [1]. It is a pattern of centrolobular nodules characterized by impaction of the terminal bronchioles. Initially, the tree-in-bud sign had been described by Im as indicating endobronchial spread of Mycobacterium tuberculosis [2], but it is now known that the pattern can occur in various peripheral airway diseases such as infection (bacterial, fungal, viral or parasitic), congenital or idiopathic disorders (obliterative bronchiolitis, panbronchiolitis), inhalation of foreign substances, immunologic tissue disorders, and peripheral pulmonary vascular diseases (neoplastic pulmonary emboli) [1, 3, 4]. Because the lung bases are visible in nearly all abdomen CT studies, recognition of this sign is important for abdominal imagers.

The lateral crescent sign

The lateral crescent sign was first described by Burkhardt et al. [1]. This sign represents the lateral compression and stretching of the fat of the inguinal canal and its contents by the hernia sac. The contents of the inguinal canal are the testicular vessels, vas deferens, and branches of the genitofemoral nerve (men) or the round ligament together with branches of the ilio inguinal nerve (women) [1]. This sign is useful for the diagnosis of early direct inguinal hernia [1]. Direct inguinal hernias (less common than the indirect type) are usually acquired and with an incidence increasing with age [2, 3]. They protrude through the Hesselbach triangle above the inguinal ligament and lie medial to the inferior epigastric vessels [1]. Direct inguinal hernias are more frequently observed in men and have a lesser rate of complications (such as strangulation) compared to indirect inguinal or femoral hernias [2, 3]. In the direct form of inguinal hernia, the contents of the inguinal canal are compressed and laterally deviated by the herniated omentum or viscera into a semi-circle of tissue (Fig. 1A, B) that resembles a crescent moon (Fig. 2). This sign is more commonly observed at early stages of direct inguinal hernia. With

Fat halo sign

The fat halo sign corresponds to a widened and fat-infiltrated submucosal layer of the bowel (small or large bowel) that can been seen in patients with inflammatory bowel diseases, such as Crohn’s disease or ulcerative colitis, mostly seen in chronic forms of the disease [1–3]. This sign is not entirely specific, as it has been described in cases of graft vs. host disease, and also as a normal finding—possibly related to obesity—in the absence of clinical or radiological evidence of inflammatory bowel disease [4]. On abdominal CT, the thickened bowel wall presents with three different layers: a fatty submucosa with low attenuation value (between 18 and – 64 HU), located between a normally enhancing mucosa (inner layer) and muscularis propria/serosa (outer layer) (Figs. 1 and 2 ). This sign also can be observed on CT without contrast enhancement, due to the very different attenuations of the three bowel wall layers [1]. The fat halo sign should be differentiated from the target sign, which is due to submucosal edema [5].

The cluster sign

The cluster sign, or ‘‘cluster of grapes sign’’ (Fig. 1) was first described by Jeffrey et al. in 1988 to describe multiple small adjacent hepatic abscesses in pyogenic bacterial liver parenchymal infection [1]. On CT (Fig. 2), the lesions usually appear as rounded cavities with contents near water density, resembling poorly defined hepatic cysts, with rim or capsular peripheral enhancement [2]. On MR, the clustered liver abscesses display low signal intensity on T1-weighted images and high signal intensity on T2-weighted images [3]. The clustered appearance generally is not seen with fungal or mycobacterial microabscesses [1]. The differential diagnosis includes metastases, infarction, biliary cystadenocarcinoma and macronodular mycobacterial infection [2, 3].

The Champagne sign

The champagne sign or ‘‘effervescent gallbladder’’ is a term used to describe the hyperechoic appearance of air bubbles secondary to gas formation in the gallbladder lumen related to necrosis in acute emphysematous cholecystitis [1, 2]. It was first described by Hegner on plain radiographs in 1931 [3]. On ultrasound, the air in the gallbladder lumen appears highly echogenic with low-level posterior shadowing and reverberation artifact (Fig. 1), due to the gas within the lumen of the gallbladder. A less common appearance consists of tiny hyperechoic foci within the lumen released from gas-producing bacteria. These hyperechoic foci are reminiscent of champagne bubbles rising inside a flute of champagne (Fig. 2). Abdominal CT (enhanced or not) confirms the diagnosis by identifying gas within the gallbladder lumen [1, 2].

The hourglass sign

The Hourglass sign is a useful imaging clue for diagnosing diaphragmatic ruptures with viscera herniation on multidetector CT, with a sensitivity ranging from 16% to 63% and a specificity around 98%–100%. This sign is also commonly found in the literature under the name “Collar sign,” first described in 1995 by Worthy et al. It refers to the waistlike constriction of the herniated structure at the site of the diaphragmatic rupture.