Clinical performance testing of the automated haematology analyzer XN-31 prototype using whole blood samples from patients with imported malaria in Japan.

BACKGROUND: The automated haematology analyzer XN-31 prototype (XN-31p) is a new flow cytometry-based device developed to measure the number and the ratio of malaria-infected red blood cells (MI-RBC) with a complete blood count (CBC). The XN-31p can provide results in about one minute and also can simultaneously provide information on the malaria parasite (Plasmodium) species. In this study, clinical testing of the XN-31p was performed using blood samples from patients with imported malaria in Japan. METHODS: Blood samples were collected from 80 patients who visited the hospital of the National Center for Global Health and Medicine, Tokyo, Japan, for malaria diagnosis from January 2017 to January 2019. The test results by the XN-31p were compared with those by other standard methods, such as microscopic observation, rapid diagnostic tests and the nested PCR. RESULTS: Thirty-three patients were diagnosed by the nested PCR as being malaria positive (28 Plasmodium falciparum, 2 Plasmodium vivax, 1 Plasmodium knowlesi, 1 mixed infection of P. falciparum and Plasmodium malariae, and 1 mixed infection of P. falciparum and Plasmodium ovale), and the other 47 were negative. The XN-31p detected 32 patients as "MI-RBC positive", which almost matched the results by the nested PCR and, in fact, completely matched with the microscopic observations. The ratio of RBCs infected with malaria parasites as determined by the XN-31p showed a high correlation coefficient of more than 0.99 with the parasitaemia counted under microscopic observation. The XN-31p can analyse the size and nucleic acid contents of each cell, and the results were visualized on a two-dimensional cytogram termed the "M scattergram". Information on species and developmental stages of the parasites could also be predicted from the patterns visualized in the M scattergrams. The XN-31p showed a positive coincidence rate of 0.848 with the nested PCR in discriminating P. falciparum from the other species. CONCLUSIONS: The XN-31p could rapidly provide instructive information on the ratio of MI-RBC and the infecting Plasmodium species. It was regarded to be of great help for the clinical diagnosis of malaria.

Use of Membrane Potential to Achieve Transmembrane Modification with an Artificial Receptor.

We developed a strategy to modify cell membranes with an artificial transmembrane receptor. Coulomb force on the receptor, caused by the membrane potential, was used to achieve membrane penetration. A hydrophobically modified cationic peptide was used as a membrane potential sensitive region that was connected to biotin through a transmembrane oligoethylene glycol (OEG) chain. This artificial receptor gradually disappeared from the cell membrane via penetration despite the presence of a hydrophilic OEG chain. However, when the receptor was bound to streptavidin (SA), it remained on the cell membrane because of the large and hydrophilic nature of SA.

[A Survey of Health Food Use and Patient Satisfaction among Patients Undergoing Cancer Pharmacotherapy].

This study aimed to clarify the situation of use of health foods by patients and the level of satisfaction of patients in order to make use of information on cases where patients undergoing cancer medication therapy use health foods. Between May 7, 2018 and June 29, 2018, we conducted a questionnaire survey of patients with progressive cancer who were undergoing cancer chemotherapy at Ogaki Municipal Hospital. In addition, we conducted a multivariate analysis of patients who were using health foods and those who were not. The questionnaire items included the objectives of use, product effectiveness and satisfaction, and QOL. The rate of health food use was 81/281 (29.5%). The primary objectives of use were, "to maintain health" (29.8%) and "to alleviate symptoms" (24.0%). The primary sources of information about health foods were "a friend" (50.6%) and "TV" (13.5%). The satisfaction level was 0-3 points in 8.3% of patients, 4-6 points in 38.1% of patients, and 7-10 points in 53.6% of patients. For "stage of illness (recurrence)," the odds ratio was 1.810 (95% CI, 1.040-3.150; p=0.035), and for "QOL value," the odds ratio was 2.210 (95% CI, 1.220-4.020; p=0.009), indicating that these factors had a significant influence on health food use. Health foods tended to be used in patients who had recurring cancer with low QOL and various symptoms, and friends and other people close to the patient had a large influence on the patient's decision. It was clear that the patients' satisfaction level was high.