Juxta-adrenal Ancient Schwannoma: A Rare Retroperitoneal Tumor

Retroperitoneal schwannoma is a rare tumor that is often misdiagnosed as malignancy due to a concerning appearance on cross-sectional imaging. Pathology and immunohistochemistry form the gold standard for diagnosis; as such, local excision is the treatment of choice for this disease. We present two cases of juxta-adrenal ancient schwannoma that were treated with adrenalectomy and discuss the current literature regarding this entity.Key words: Ancient schwannoma, Adrenal tumor, AdrenalectomySchwannomas are tumors of the nerve sheath cells that surround peripheral nerves throughout the body. These tumors are typically benign in nature, although malignant transformation has been documented in rare cases. Schwannomas are most often found in women between the ages of 20 and 50 years; although they can be found throughout the peripheral nervous system, they seldom present in the retroperitoneum.¹ Less than 0.2% of incidental adrenal and periadrenal masses are eventually diagnosed as schwannoma,² and only 0.7% of schwannomas are found in the retroperitoneal space.^3,4 These tumors are classically well encapsulated, hypervascular, and can appear heterogeneous, making them difficult to distinguish from more concerning lesions through imaging studies alone.Schwannomas, or neurilemmomas, originate from neural crest cells and are histologically composed of spindle-shaped tumor cells organized in the Antoni A and Antoni B regions (cellularly dense and sparse, respectively).⁵ The term ancient schwannoma was coined in 1951 by Ackerman and Taylor to describe an uncommon histologic subtype with only occasional tumor cells surrounded by a hyalinized matrix, more characteristic of the degeneration associated with a long-standing and slow-growing mass.⁶Given the paucity of data regarding juxta-adrenal and other retroperitoneal ancient schwannomas, and their similar appearance to more invasive cancers, we discuss two cases of juxta-adrenal ancient schwannoma that initially presented as a malignant-appearing adrenal mass.     

Modulation of acute cadmium toxicity by Emblica officinalis fruit in rat

The efficacy of Emblica officinalis in modifying the acute cytotoxicity of cadmium in male rats was evaluated. Oral administration of Emblica fruit juice (500 mg/kg, b.w.) for 8 days followed by a single toxic dose of Cd as CdCl2 (3 mg/kg,b.w. ip), considerably reduced the mortality in rats as well as prevented to some extent the cadmium induced histopathological damage in testis, liver and kidneys. Biochemical investigation also revealed reduced levels of Cd induced serum glutamate oxaloacetate transaminase, glutamate pyruvate transaminase and gamma glutamyltranspeptidase. The enhanced levels of Cd and lipid peroxidation in liver, kidney, and testes and metallothionein and total sulphydryl in liver and kidney by Cd were significantly reduced by Emblica pretreatment. These results suggest cytoprotective potential of Emblica fruit in acute cadmium toxicity which could be due to its multiple role in biological system.     

Thermostable microbial xylanases for pulp and paper industries: trends,applications and further perspectives

World Journal of Microbiology and Biotechnology - As obligate aerobic soil organisms, the ability of Azotobacter species to fix nitrogen is unusual given that the nitrogenase complex requires a...     

Biochemical and biophysical characterization of a peroxidase isolated from Euphorbia tirucalli with antifungal activity

A novel peroxidase from the latex of medicinal plant Euphorbia tirucalli (Pencil tree) belonging to the Euphorbiaceae family is purified to homogeneity using cation exchange chromatography. The enzyme, named Euphorbia tirucalli peroxidase (ETP) has a molecular mass of 38.8?kDa. The isoelectric point of the enzyme is pH 7.5 with optimum pH and temperature of pH 6.0 and 50?°C respectively. The extinction coefficient (?_280 nm^1%) of the enzyme is 20.52 and the molecular structure consists of 13 tryptophan, nine tyrosine, and eight cysteine residues forming four disulfide bridges. Three peptide sequences, ALVHKECGPVVSCSDIVAIAARDSVVLTGGPKYDV, YYVDLMNRQGLFTSDQDLYT DKR, and MGQLEVVTGNQGEIR are obtained by MS/MS analysis which confirms the novelty of the enzyme. ETP belongs to α/β class of proteins with secondary structural features of approximately 10% α-helix, 29% β-sheet, and 61% random coil. ETP exhibits antifungal activity against Aspergillus niger and Candida albicans which shows its role in defense mechanism of plants. The enzyme is stable and retains its activity over a broad range of pH and temperature or prolonged storage at 4?°C. Simple purification, high yield, and stability enable exploration of the peroxidase for structure–function relationship studies as well as other biotechnological applications.     

Effects of side group functionality and molecular weight on the activity of synthetic antimicrobial polypeptides

The rapid emergence of antibiotic-resistant bacteria along with increasing difficulty in biofilm treatment has caused an immediate need for the development of new classes of antimicrobial therapeutics. We have developed a library of antimicrobial polypeptides, prepared by the ring-opening polymerization of γ-propargyl-L-glutamate N-carboxyanhydride and the alkyne-azide cycloaddition click reaction, which mimic the favorable characteristics of naturally occurring antimicrobial peptides (AmPs). AmPs are known not to cause drug resistance as well as prevent bacteria attachment on surfaces. The ease and scale of synthesis of the antimicrobial polypeptides developed here are significantly improved over the traditional Merrifield synthetic peptide approaches needed for naturally occurring antimicrobial peptides and avoids the unique challenges of biosynthetic pathways. The polypeptides range in length from 30 to 140 repeat units and can have varied side group functionality, including primary, secondary, tertiary, and quaternary amines with hydrocarbon side chains ranging from 1 to 12 carbons long. Overall, we find these polypeptides to exhibit broad-spectrum activity against both Gram positive and Gram negative bacteria, namely, S. aureus and E. coli , while having very low hemolytic activity. Many of the polypeptides can also be used as surface coatings to prevent bacterial attachment. The polypeptide library developed in this work addresses the need for effective biocompatible therapeutics for drug delivery and medical device coatings.     

Resistance Evolution against Host-directed Antiviral Agents: Buffalopox Virus Switches to Use p38-ϒ under Long-term Selective Pressure of an Inhibitor Targeting p38-α

Host-dependency factors have increasingly been targeted to minimize antiviral drug resistance. In this study, we have demonstrated that inhibition of p38 mitogen-activated protein kinase (a cellular protein) suppresses buffalopox virus (BPXV) protein synthesis by targeting p38-MNK1-eIF4E signaling pathway. In order to provide insights into the evolution of drug resistance, we selected resistant mutants by long-term sequential passages (P; n = 60) in the presence of p38 inhibitor (SB239063). The P60-SB239063 virus exhibited significant resistance to SB239063 as compared to the P60-Control virus. To provide mechanistic insights on the acquisition of resistance by BPXV-P60-SB239063, we generated p38-α and p38-ϒ (isoforms of p38) knockout Vero cells by CRISPR/Cas9-mediated genome editing. It was demonstrated that unlike the wild type (WT) virus which is dependent on p38-α isoform, the resistant virus (BPXV-P60-SB239063) switches over to use p38-ϒ so as to efficiently replicate in the target cells. This is a rare evidence wherein a virus was shown to bypass the dependency on a critical cellular factor under selective pressure of a drug.