Gastric Syphilis Mimicking Lymphoma: A Case Report.

Gastric syphilis is a rare manifestation of syphilis that occurs in about 1% of cases and is often overlooked due to its non-specific signs and symptoms. We report a case of a 28-year-old Chinese woman who presented with epigastric pain, nausea, vomiting, hematemesis, alopecia, and weight loss. She tested positive for Helicobacter pylori (H. pylori), with rapid plasma reagin (RPR) and Treponema pallidum particle assay (TPPA) tests showing titers of 1:128 and 1:320, respectively. CT imaging revealed thickening of the gastric wall, exudation around the antrum, and multiple lymphadenopathies. Gastroscopy showed multiple irregular ulcers, which resembled lymphoma. However, biopsy results did not support the presence of lymphoma, but immunohistochemistry showed an abundance of syphilis spirochetes in the mucosal lamina propria and glands. This led to a diagnosis of gastric syphilis. The patient received standard treatment for syphilis as well as anti-H. pylori therapy, and her symptoms and endoscopic findings gradually improved and eventually resolved. We hope that this case report can provide valuable insights into the diagnosis and management of gastric syphilis, which can mimic other diseases like lymphoma.

The Predominance of a Specific Genotype of Cryptococcus neoformans var. Grubii in China and Japan.

Background: The extensive deployment of molecular genotyping methods is the top reliable keyword to characterize the population genetic structure of C. neoformans in the past decade. However, studies involving genotypic analysis of C. neoformans var. grubii from China and Japan are limited. Objectives: We address this challenge to determine the genotype distribution of C. neoformans var. grubii strains from China and Japan. Methods: Genotypic analysis of 52 C. neoformans var. grubii isolates was performed using multilocus microsatellite typing (MLMT) based on the sequence analysis of 3 functional genes. In order to place the herein-studied strains into the global picture, 22 strains randomly selected from the 52 strains studied by MLMT were also analyzed by restriction fragment length polymorphism analysis of the orotidine monophosphate pyrophosphorylase gene (URA5-RFLP), M13 PCR-fingerprinting, and multilocus sequence typing (MLST). Results: MLMT classified 46 (88.5%) of the 52 strains as genotype MLMT-17. The high prevalence of the MLMT-17 type was observed for environmental and clinical isolates from China and Japan. URA5-RFLP analysis, M13 PCR-fingerprinting, and MLST showed that most of these belong to the VNI/ST5 (M5) genotype. Conclusions: Our study suggests the predominance of a specific genotype of C. neoformans var. grubii in China and Japan.

Microfluidic Particle Separation and Detection System Based on Standing Surface Acoustic Wave and Lensless Imaging.

OBJECTIVE: Separation and detection of micro-particles or cells from bio-samples by point-of-care (POC) systems are critical for biomedical and healthcare diagnostic applications. Among various microfluidic separation techniques, acoustophoresis-based technique has the advantages of label-free and good biocompatibility. However, most of the existing separation techniques are bulky and require additional equipment for analysis. METHODS: We proposed a platform, which integrates an acoustophoresis-based separation device and a lensless imaging sensor into a compact standalone system to tackle this challenge. Standing Surface Acoustic Wave (SSAW) is utilized for label-free particle separation, while lensless imaging is employed for seamless particle detection and counting using self-developed dual-threshold motion detection algorithms. In particular, we specially optimized the design of microfluidic channel and interdigital transducers (IDTs) for higher performance bioparticle separation, designed a heat dissipation system for the suppression of fluid temperature, and proposed a novel frequency-temperature-curve based method to determine the appropriate signal driving frequency for IDTs. RESULTS: At 2 µL/min flow rate, separation efficiency of 93.52% and purity of 94.29% for 15 µm microbead were achieved in mixed 5µm and 15µm microbead solution at a 25 dBm RF driving power, and similar results for mixed 10 µm and 15 µm microbead solution. CONCLUSIONS: The results showed that the integrated platform has an excellent capability to seamlessly separate, distinguish, and count microbeads of different sizes. SIGNIFICANCE: Such a platform and the design methodologies offer a promising POC solution for label-free cell separation and detection in biomedical diagnostics.