Current clinical treatment of infection, the main etiological factor in the development of gastritis, gastric ulcers, and gastric carcinoma, requires a combination of at least two antibiotics and one proton pump inhibitor. However, such triple therapy suffers from progressively decreased therapeutic efficacy due to the drug resistance and undesired killing of the commensal bacteria due to poor selectivity. Here, we report the development of antimicrobial polypeptide-based monotherapy, which can specifically kill under acidic pH in the stomach while inducing minimal toxicity to commensal bacteria under physiological pH. Specifically, we designed a class of pH-sensitive, helix-coil conformation transitionable antimicrobial polypeptides (HCT-AMPs) (PGA)--(PHLG-MHH), bearing randomly distributed negatively charged glutamic acid and positively charged poly(γ-6--(methyldihexylammonium)hexyl-l-glutamate) (PHLG-MHH) residues. The HCT-AMPs showed unappreciable toxicity at physiological pH when they adopted random coiled conformation. Under acidic condition in the stomach, they transformed to the helical structure and exhibited potent antibacterial activity against , including clinically isolated drug-resistant strains. After oral gavage, the HCT-AMPs afforded comparable killing efficacy to the triple-therapy approach while inducing minimal toxicity against normal tissues and commensal bacteria, in comparison with the remarkable killing of commensal bacteria by 65% and 86% in the ileal contents and feces, respectively, following triple therapy. This strategy renders an effective approach to specifically target and kill in the stomach while not harming the commensal bacteria/normal tissues.

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Electrosynthesis has received great attention among researchers in both academia and industry as an ideal technique to promote single electron reduction without the use of expensive catalysts. In this work, we report the electrochemical reduction of Katritzky salts to alkyl radicals by sacrificing the easily accessible metal anode. This catalyst and electrolyte free platform has broad applicability to single electron transfer chemistry, including fluoroalkenylation, alkynylation and thiolation. The deaminative functionalization is facilitated by the rapid molecular diffusion across microfluidic channels, demonstrating the practicality that outpaces the conventional electrochemistry setups.

Hepatic perivascular epithelioid cell neoplasm (PEComa) is a rare type of neoplasm derived from mesenchymal tumors that is often misdiagnosed as hepatocellular carcinoma (HCC), hepatic hemangioma or other liver malignancies. The clinical and histological characteristics of PEComa have yet to be fully documented. To optimize the diagnosis and treatment of the disease, a retrospective analysis was performed to investigate the clinicopathological characteristics of 7 patients diagnosed with hepatic PEComa in the Sun Yat-Sen Memorial Hospital between January 2004 and December 2015. Briefly, all the patients lacked specific symptoms, and a serological examination provided no further useful information. Additionally, non-specific imaging manifestations were observed. Microscopically, detection of epithelioid or spindle-shaped cells with adipocytes was suggestive of the disease, and an analysis of biomarkers, including the monoclonal antibody HMB-45, the melanocytic differentiation marker, Melan-A, and smooth muscle α-actin (SMA), helped to confirm the diagnosis. Regarding the treatment, 6 patients (85.7%) received surgical resection procedures, and 1 patient (14.3%) was admitted for tumor arterial embolization and percutaneous microwave coagulation therapy. After a follow-up period of 12–20 months, no recurrence was observed. Taken together, hepatic PEComa should be suspended in patients with a liver tumor with asymptomatic manifestation and normal serological test results. In imaging studies, hepatic PEComa was able to mimic HCC, hepatic hemangioma and metastatic tumor, although the mass did not invade the adjacent organs and vessel. The definitive diagnosis was made on the basis of the typical morphological features and notable markers of the tumor tissue. It is recommended that patients with PEComa in a benign pattern deserve serial imaging follow-up, but surgery is indicated in patients suffering from large tumors (>5 cm), or progressive enlargement or malignant tendency.