Hepatic stearoyl-CoA desaturase-1 deficiency induces fibrosis and hepatocellular carcinoma-related gene activation under a high carbohydrate low fat diet.

Stearoyl-CoA desaturase-1 (SCD1) is a pivotal enzyme in lipogenesis, which catalyzes the synthesis of monounsaturated fatty acids (MUFA) from saturated fatty acids, whose ablation downregulates lipid synthesis, preventing steatosis and obesity. Yet deletion of SCD1 promotes hepatic inflammation and endoplasmic reticulum stress, raising the question of whether hepatic SCD1 deficiency promotes further liver damage, including fibrosis. To delineate whether SCD1 deficiency predisposes the liver to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC), we employed in vivo SCD1 deficient global and liver-specific mouse models fed a high carbohydrate low-fat diet and in vitro established AML12 mouse cells. The absence of liver SCD1 remarkably increased the saturation of liver lipid species, as indicated by lipidomic analysis, and led to hepatic fibrosis. Consistently, SCD1 deficiency promoted hepatic gene expression related to fibrosis, cirrhosis, and HCC. Deletion of SCD1 increased the circulating levels of Osteopontin, known to be increased in fibrosis, and alpha-fetoprotein, often used as an early marker and a prognostic marker for patients with HCC. De novo lipogenesis or dietary supplementation of oleate, an SCD1-generated MUFA, restored the gene expression related to fibrosis, cirrhosis, and HCC. Although SCD1 deficient mice are protected against obesity and fatty liver, our results show that MUFA deprivation results in liver injury, including fibrosis, thus providing novel insights between MUFA insufficiency and pathways leading to fibrosis, cirrhosis, and HCC under lean non-steatotic conditions.

Biocorrosion and Cytotoxicity Studies on Biodegradable Mg-Based Multicomponent Alloys.

Magnesium-based multicomponent alloys with different compositions, namely Mg60Al20Zn5Cu10Mn5 (Mg60 alloy), Mg70Al15Zn5Cu5Mn5 (Mg70 alloy), and Mg80Al5Cu5Mn5Zn5 (Mg 80) alloys, were prepared using the disintegrated melt deposition technique. The DMD technique is a distinctive method that merges the benefits from gravity die casting and spray forming. This approach facilitates high solidification rates, process yields, and reduced metal wastage, resulting in materials with a fine microstructure and minimal porosity. Their potential as biodegradable materials was assessed through corrosion in different simulated body fluids (SBFs), microstructure, and cytotoxicity tests. It was observed that the Mg60 alloy exhibited low corrosion rates (~× 10-5 mm/year) in all SBF solutions, with a minor amount of corrosive products, and cracks were observed. This can be attributed to the formation of the Mg32(AlZn)49 phase and to its stability due to Mg(OH)2 film, leading to excellent corrosion resistance when compared to the Mg70 and M80 alloys. Conversely, the Mg80 alloy exhibited high corrosion rates, along with more surface degradation and cracks, due to active intermetallic phases, such as Al6Mn, Al2CuMg, and Al2Cu phases. The order of corrosion resistance for the Mg alloy was found to be ASS > HBSS > ABP > PBS. Further, in vitro cytotoxicity studies were carried out using MDA-MB-231 tumor cells. By comparing all three alloys, in terms of proliferation and vitality, the Mg80 alloy emerged as a promising material for implants, with potential antitumor activity.

Solitary Isolated Oropharyngeal Neurofibroma Presenting With Dysphagia in the Setting of Von Recklinghausen's Disease.

A 24-year-old man with von Recklinghausen's disease presented with complaints of difficulty in swallowing for 6 months and change of voice for 3 months. He also had recent-onset difficulty in breathing. Telelaryngoscopy and subsequent contrast-enhanced computed tomography scan revealed a well-defined, smooth submucosal mass in the oropharynx (attached to the posterior pharyngeal wall, superior to the level of left aryepiglottic fold), obscuring the ipsilateral pyriform fossa, and nearly blocking the pharyngeal lumen. The mass was removed with endoscopic coblation-assisted laryngeal surgery, and subsequent histopathology revealed it to be neurofibroma. Neurofibromas are rare neoplasms to be encountered in the oropharynx. However, in the setting of von Recklinghausen's disease (neurofibromatosis type 1), one or more well-demarcated, submucosal nodular lesions in the upper aerodigestive tract may be considered as neurofibromas, and workup and treatment should be directed accordingly based on this clinical presumption. Endoscopic coblation during laryngeal surgery can effectively be used as a surgical tool to excise such lesions. It provides a relatively bloodless field compared to the conventional cold steel excision, and reduces the risk of complications at surgery and during the follow-up period. This clinical record illustrates the presentation and management of a solitary, isolated oropharyngeal neurofibroma in a man suffering from von Recklinghausen's disease. It further emphasizes the role of endoscopic coblation-assisted laryngeal surgery in this setup, and the need to maintain a low threshold of suspicion in having a provisional clinical diagnosis of such lesions.

Craniocervical Tetanus: A Practical Consideration During Work-up of Acute-Onset Trismus.

This clinical record revisits the classical and pathognomonic features of craniocervical tetanus in a 65-year-old farmer who presented with acute-onset trismus, multiple cranial nerve pareses (III, IX, and X), risus sardonicus, and spasm of the head-neck musculature. This paper explores the relevant literature and presents a brief pictorial analysis of the global epidemiologic data. With most countries successfully adopting the maternal and neonatal tetanus elimination (MNTE) program, the incidence and mortality of tetanus across age groups have sharply reduced in high-income and most middle-income nations. In adults, tetanus is now encountered in specialized situations like waning immunity and incomplete vaccination, in the resource-poor and low-income nations, in countries achieving MNTE recently, and as cluster cases in the aftermath of natural disasters involving human settlements. Therefore, present-day practicing otolaryngologists and residents who have limited exposure to the tell-tale clinical features of craniocervical tetanus should consider it during work-up of acute-onset trismus in adults in susceptible situations and with a conducive background. The clinical spectrum of craniocervical tetanus as depicted in this report, including the demonstration of the pathognomonic positive spatula test, provides valuable learning points for otolaryngologists in this regard.

Identification of antiviral phytochemicals from cranberry as potential inhibitors of SARS-CoV-2 main protease (Mpro).

Cranberry phytochemicals are known to possess antiviral activities. In the current study, we explored the therapeutic potential of cranberry against SARS-CoV-2 by targeting its main protease (Mpro) enzyme. Firstly, phytochemicals of cranberry origin were identified from three independent databases. Subsequently, virtual screening, using molecular docking and molecular dynamics simulation approaches, led to the identification of three lead phytochemicals namely, cyanidin 3-O-galactoside, ß-carotene and epicatechin. Furthermore, in vitro enzymatic assays revealed that cyanidin 3-O-galactoside had the highest inhibitory potential with IC50 of 9.98 µM compared to the other two phytochemicals. Cyanidin 3-O-galactoside belongs to the class of anthocyanins. Anthocyanins extracted from frozen cranberry also exhibited the highest inhibitory potential with IC50 of 23.58 µg/ml compared to the extracts of carotenoids and flavanols, the class for ß-carotene and epicatechin, respectively. Finally, we confirm the presence of the phytochemicals in the cranberry extracts using targeted LC-MS/MS analysis. Our results, therefore, indicate that the identified cranberry-derived bioactive compounds as well as cranberry could be used for therapeutic interventions against SARS-CoV-2.

GC-MS based metabolite profiling and angiotensin I-converting enzyme inhibitory property of black tea extracts

Abstract Angiotensin I-converting enzyme inhibitors are used as therapeutic agents for the treatment of hypertension. Regular consumption of black tea (Camellia sinensis (L.) Kuntze, Theaceae) has been reported to lower blood pressure. The aims of the present work were to compare chemical composition and angiotensin I-converting enzyme inhibitory properties of infusion and decoction of four samples of black tea. GC/MS based metabolomics approach helped in identification of fifty-one metabolites including ten organic acids, one inorganic acid, sixteen amino acids, two sugars, five sugar alcohols, fifteen phenols and flavonoids, two fatty acids from infusions and decoctions of four black tea samples. Partial least squares discriminant analysis and orthogonal partial least squares discriminant analysis models showed good classification among the two groups, diffusion and infusion, based on metabolites. Both infusion and decoction inhibited the enzyme. However, the activity differed with samples. Multivariate analysis also segregated extracts on the basis of activity. Thearubigin, theaflavin, catechin inhibited the enzyme. Epicatechin, epigallocatechin gallate, gallic acid, caffeine showed lower activity.