Primary Thymic Mucosa-Associated Lymphoid Tissue Lymphoma: Diagnostic Tips

AbstractMucosa-associated lymphoid tissue (MALT) lymphoma arising in the thymus is extremely rare and little is known regarding its clinicopathological features. This study examined the clinicopathological features of nine cases of thymic MALT lymphoma. Most patients had autoimmune disease or hyperglobulinemia, and they also had cysts in the tumors. Both increased serum autoantibody levels and polyclonal serum immunoglobulin levels remained essentially unchanged after total thymectomy in all patients. Thymic MALT lymphoma needs to be included in the differential diagnosis in Asian patients with a cystic thymic mass accompanied by autoimmune disease or hyperglobulinemia

CID12261165, a flavonoid compound as antibacterial agents against quinolone-resistant Staphylococcus aureus

Abstract Flavonoids are plant-produced secondary metabolites that are found ubiquitously. We have previously reported that apigenin, a class of flavonoid, has unique antimicrobial activity against Staphylococcus aureus (S. aureus), one of the major human pathogens. Apigenin inhibited fluoroquinolone-resistant S. aureus with DNA gyrase harboring the quinolone-resistant S84L mutation but did not inhibit wild-type DNA gyrase. In this study, we describe five flavonoids, quercetin, luteolin, kaempferol, baicalein, and commercially available CID12261165, that show similar antimicrobial activity against fluoroquinolone-resistant S. aureus. Among them, CID12261165 was the most effective with MIC values of ≤ 4 mg/L against quinolone-resistant S. aureus strains. In vitro DNA cleavage and supercoiling assays demonstrated inhibitory activity of CID12261165 against mutated DNA gyrase, whereas activity against wild-type DNA gyrase was not observed. CID12261165 also inhibited quinolone-resistant Enterococci with an MIC value of 8 mg/L. While fluoroquinolone-resistant amino acid replacements can improve the fitness of bacterial cells, it is unknown why quinolone-susceptible S. aureus strains were predominant before the introduction of fluoroquinolone. The present study discusses the current discrepancies in the interpretation of antimicrobial activities of flavonoids, as well as the possible reasons for the preservation of wild-type DNA gyrase wherein the environmental flavonoids cannot be ignored

Hepatocellular Carcinoma Mimicking Liver Abscesses in a Cirrhotic Patient with Severe Septic Shock as a Result of Salmonella O9 HG Infection

We describe a case of severe Salmonella O9 HG sepsis with a mass in the liver, which was diagnosed as hepatocellular carcinoma (HCC) by autopsy of the liver. The patient was a 67-year-old man with chronic high blood pressure. In addition, he was an alcoholic and had been drinking every day for many years. He had had a dinner of ‘sukiyaki’ with a raw egg two days before admission. The next morning, he had developed vomiting, diarrhea, and abdominal pain. Salmonella O9 HG was found in the blood and stool cultures. In the computed tomography (CT) finding of the liver, there was a 2 cm early-enhanced mass with a multilocular structure, with ringed enhancement and daughter nodes. Since we thought that the mass was a liver abscess, we performed needle aspiration from the liver mass and were able to withdraw blood. Despite adequate antibiotic treatment, the patient died as a result of complications on the 55th day after admission. After the patient’s death, we conducted an autopsy. There were two HCC masses, a moderately-differentiated and a well-differentiated mass, as a result of alcoholic cirrhosis of the liver. As the HCC had multilocular cyst-like structures, which were fiber- and necrosis-rich, CT images of the liver masses resembled abscesses

Interaction Analysis of FABP4 Inhibitors by X‑ray Crystallography and Fragment Molecular Orbital Analysis

X-ray crystal structural determination of FABP4 in complex with four inhibitors revealed the complex binding modes, and the resulting observations led to improvement of the inhibitory potency of FABP4 inhibitors. However, the detailed structure–activity relationship (SAR) could not be explained from these structural observations. For a more detailed understanding of the interactions between FABP4 and inhibitors, fragment molecular orbital analyses were performed. These analyses revealed that the total interfragment interaction energies of FABP4 and each inhibitor correlated with the ranking of the <i>K</i>_i value for the four inhibitors. Furthermore, interactions between each inhibitor and amino acid residues in FABP4 were identified. The oxygen atom of Lys58 in FABP4 was found to be very important for strong interactions with FABP4. These results might provide useful information for the development of novel potent FABP4 inhibitors