A new ion sampling interface for an electrospray ionization 3D ion trap mass spectrometer system is described. The interface uses linear rf quadrupoles as ion guides and ion traps to enhance the performance of the 3D trap. Trapping ions in the linear quadrupoles is demonstrated to improve the duty cycle of the system. Dipolar excitation of ions trapped in a linear quadrupole is used to eject unwanted ions. A resolution of ejection of up to 254 is demonstrated for protonated reserpine ions (m/z 609.3). A composite waveform with a notch in frequency space is used to eject a wide range of matrix ions and to isolate trace analyte ions in a linear quadrupole before ions are injected into the 3D trap. This is useful to overcome space charge problems in the 3D trap caused by excess matrix ions. For trace reserpine in a 500-fold molar excess of poly(propylene glycol) (PPG), it is demonstrated that the resolution and sensitivity of the 3D trap can be increased dramatically with ejection of the excess PPG matrix ions. In comparison to ejection of matrix ions in the 3D trap with a similar broad-band waveform, a 5-fold increase in sensitivity with a 7 times shorter acquisition time was achieved.

After fecal microbiota transplantation (FMT) to treat Clostridioides difficile infection (CDI), cognitive improvement is noticeable, suggesting an essential association between the gut microbiome and neural function. Although it is known that the gut microbiome is linked with cognitive function, whether FMT may lead to cognitive improvement in patients with neurodegenerative disorders remains to be elucidated. We present the case of a 90-year-old woman with Alzheimer's dementia and severe CDI who underwent FMT. Cognitive function testing (Mini-Mental State Examination, Montreal Cognitive Assessment, and Clinical Dementia Rating assessment) was performed one month before FMT and one week and one month after FMT. We collected the patients' fecal samples before FMT and 3 weeks after FMT to compare the microbiota composition. The 16S rRNA gene amplicons were analyzed using the QIIME2 platform (version 2020.2) and the Phyloseq R package. The linear discriminant analysis effect size was performed to determine the taxonomic difference between pre-and post-FMT. Functional biomarker analysis using the Kruskal-Wallis H test was performed between the pre-and post-FMT. The cognitive function tests after FMT showed an improvement compared to the tests before the procedure. FMT changed the microbiota composition in recipient feces. We found that the genera were reported to be associated with cognitive function. In addition, short-chain fatty acids were found to be significantly different between before and after FMT. This finding suggests the presence of an association between the gut microbiome and cognitive function. Further, it emphasizes the need for clinical awareness regarding the effect of FMT on the brain-gut-microbiome axis and its potential as a therapy for patients with dementia.

No abstract

Helicobacter pylori deregulates the genes that control homeostasis between apoptosis and cell proliferation of gastric epithelial cells. Nuclear factor-kappaB (NF-kappaB) has an important role in H. pylori-induced apoptosis in gastric epithelial cells. The peroxisome proliferator-activated receptor-gamma ligand 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)) regulates growth and the signaling cascade in H. pylori-infected gastric epithelial cells. In the present study, we determined whether 15d-PGJ(2) inhibits apoptosis by regulating apoptotic gene expression and NF-kappaB activation in gastric epithelial cells infected with CagA+, VacA+H. pylori in a Korean isolate (HP99). 15d-PGJ(2) was found to inhibit H. pylori-induced DNA fragmentation and cell death. 15d-PGJ(2) induced downregulation of proapoptotic Bax and upregulation of antiapoptotic Bcl-2 as well as suppression of NF-kappaB activation caused by H. pylori in gastric epithelial cells. The results suggest that 15d-PGJ(2) inhibits apoptotic cell death by inhibiting NF-kappaB activation and apoptotic gene expression in gastric epithelial cells.

No abstract