A Method for High Throughput Free Fatty Acids Determination in a Small Section of Bovine Liver Tissue Using Supercritical Fluid Extraction Combined with Supercritical Fluid Chromatography-Medium Vacuum Chemical Ionization Mass Spectrometry.

A novel ionization technique named medium vacuum chemical ionization (MVCI) mass spectrometry (MS), which is a chemical ionization using oxonium (HO) and hydroxide (OH) formed from water, has excellent compatibility with the supercritical fluid extraction (SFE)/supercritical fluid chromatography (SFC). We have studied a method to determine free fatty acids (FFAs) in a small section of bovine liver tissue using SFE/SFC-MVCI MS analysis without further sample preparation. A series of FFA molecules interact with the C18 stationary phase, exhibiting broad chromatographic peaks when using a non-modified CO as the mobile phase.

Rapid Analysis of α-Tocopherol and Its Oxidation Products Using Supercritical Carbon Dioxide and Proton Transfer Reaction Ionization Mass Spectrometry.

We have developed a rapid and sensitive analytical method for α-tocopherol and its oxidative products by combining online hyphenation of supercritical fluid extraction-supercritical fluid chromatography (SFC) with proton transfer reaction (PTR) ionization mass spectrometry (MS). α-Tocopherol is a well-known antioxidant that plays a vital role in the antioxidant defense system in plant cells. However, studies on the cellular mechanisms of α-tocopherol have been limited owing to the lack of a rapid analytical method, which limits the comparison of plant cells incubated in various conditions.

Attempts to Detect Lipid Metabolites from a Single Cell Using Proton-Transfer-Reaction Mass Spectrometry Coupled with Micro-Scale Supercritical Fluid Extraction: A Preliminary Study.

Proton-transfer-reaction (PTR) mass spectrometry (MS), a widely used method for detecting trace-levels of volatile organic compounds in gaseous samples, can also be used for the analysis of small non-volatile molecules by using supercritical fluid as a transporter for the molecules. Supercritical fluid extraction (SFE) is a method that permits lipophilic compounds to be rapidly and selectively extracted from complex matrices. The combination of the high sensitivity of PTR MS with the SFE is a potentially novel method for analyzing small molecules in a single cell, particularly for the analysis of lipophilic compounds.

Matrix-Assisted Laser Desorption/Ionization (MALDI) Mass Spectrometry Imaging of L-4-Phenylalanineboronic Acid (BPA) in a Brain Tumor Model Rat for Boron Neutron Capture Therapy (BNCT).

Boron neutron capture therapy (BNCT) is a cell-selective particle therapy for cancer using boron containing drugs. Boron compounds are accumulated in high concentration of tens ppm level of boron in target tumors to cause lethal damage to tumor tissue. The examination of boron distribution in target tumor and normal tissue is important to evaluate the efficiency of therapy.

Boron Delivery to Brain Cells via Cerebrospinal Fluid (CSF) Circulation in BNCT of Brain-Tumor-Model Rats-Ex Vivo Imaging of BPA Using MALDI Mass Spectrometry Imaging.

The blood-brain barrier (BBB) is likely to be intact during the early stages of brain metastatic melanoma development, and thereby inhibits sufficient drug delivery into the metastatic lesions. Our laboratory has been developing a system for boron drug delivery to brain cells via cerebrospinal fluid (CSF) as a viable pathway to circumvent the BBB in boron neutron capture therapy (BNCT). BNCT is a cell-selective cancer treatment based on the use of boron-containing drugs and neutron irradiation.

Microscale supercritical fluid extraction combined with supercritical fluid chromatography and proton-transfer-reaction ionization time-of-flight mass spectrometry for a magnitude lower limit of quantitation of lipophilic compounds.

The application of proton transfer ionization reaction mass spectrometry (PTR MS) combined with microscale supercritical fluid extraction (SFE) and supercritical fluid chromatography (SFC) aiming to quantitate single-cell fatty acid analysis levels was investigated. Using a microscale extraction vessel, the obtained low limits of quantitation (LLOQs) of arachidonic acid and arachidic acid were 1.2 and 2.

Effects of Rikkunshi-To, a Japanese kampo medicine, on donepezil-induced gastrointestinal side effects in mice.

Donepezil, an acetylcholinesterase inhibitor, is associated with gastrointestinal symptoms, such as nausea, vomiting, and anorexia, which may affect adherence to continuous therapy. Since Rikkunshi-To, a Japanese herbal medicine, activates the ghrelin signaling pathway and promotes gastrointestinal function, it is administered to prevent gastrointestinal symptoms. We herein investigated whether donepezil-induced gastrointestinal side effects in mice are ameliorated by Rikkunshi-To and if its therapeutic efficacy is mediated by ghrelin.

Analysis of Nonvolatile Molecules in Supercritical Carbon Dioxide Using Proton-Transfer-Reaction Ionization Time-of-Flight Mass Spectrometry.

Proton-transfer-reaction (PTR) mass spectrometry (MS) is capable of detecting trace-level volatile organic compounds (VOCs) in gaseous samples in real time. Therefore, PTR-MS has become a popular method in many different study areas. Most of the currently reported PTR-MS applications are designed to determine volatile compounds.

Prenatal ultrasonographic findings and fetal/neonatal outcomes of body stalk anomaly.

We studied 27 cases that were post or prenatally diagnosed with body stalk anomaly (BSA) using medical records of prenatal ultrasound findings, pregnancy outcomes, and fetal/neonatal prognosis during 1992 to 2018. Termination of pregnancy was chosen in 15 cases. Of the remaining 12 cases, seven were stillbirths and five were live births.

New Method for Improving LC/Time-of-Flight Mass Spectrometry Detection Limits Using Simultaneous Ion Counting and Waveform Averaging.

Simultaneous ion counting and waveform averaging implemented on a field-programmable gate array compiled with a high-speed digitizer was applied to ultraperformance liquid chromatography-time-of-flight mass spectrometric analysis of sulfa drugs. Ion counting was carried out by a "Peak Detection" (PKD) function that works together with signal averaging (AVG). Sulfadimidine (SDD) and sulfadimethoxine (SDMX) were measured in human serum (HS) model sample matrix.

Low-Dose Sodium Nitrite Fluid Resuscitation Prevents Lethality From Crush Syndrome by Improving Nitric Oxide Consumption and Preventing Myoglobin Cytotoxicity in Kidney in A Rat Model.

Objective: Crush syndrome (CS) is a serious medical condition characterized by muscle cell damage resulting from pressure. CS has a high mortality, even when patients receive fluid therapy. We examined whether administration of NaNO2-containing fluid can improve survival in a rat model of CS.

Structure-activity relationships of xanthocillin derivatives as thrombopoietin receptor agonist.

Xanthocillin derivatives, which show thrombopoietin receptor agonist activity, were synthesized through our developed method. Bioassay data suggest the importance of alkene geometry, the presence of substituents at the benzene ring that support hydrophobic character, and the moderate size of the molecule. One of the two isonitrile group of the natural product appears to be dispensable.

Glucose intolerance and serum aminotransferase activities in Japanese men.

Background/aims: Elevated activities of serum aminotransferase are commonly observed in patients with diabetes mellitus. Few studies have addressed the relation between glucose intolerance and serum activities of aminotransferase in free-living populations.

Methods: Using a 75 g oral glucose tolerance test, we examined the association of impaired fasting glycemia (IFG), impaired glucose tolerance (IGT), and type 2 diabetes mellitus with serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and gamma-glutamyltransferase (GGT) among 4621 men aged 49-59 years of the Japan Self-Defense Forces.