Myeloid cell dynamics correlating with clinical outcomes of severe COVID-19 in Japan

An expanded myeloid cell compartment is a hallmark of severe coronavirus disease 2019 (COVID-19). However, data regarding myeloid cell expansion have been collected in Europe, where the mortality rate by COVID-19 is greater than those in other regions including Japan. Thus, characteristics of COVID-19-induced myeloid cell subsets remain largely unknown in the regions with low mortality rates. Here, we analyzed cellular dynamics of myeloid-derived suppressor cell (MDSC) subsets and examined whether any of them correlate with disease severity and prognosis, using blood samples from Japanese COVID-19 patients. We observed that polymorphonuclear (PMN)-MDSCs, but not other MDSC subsets, transiently expanded in severe cases but not in mild or moderate cases. Contrary to previous studies in Europe, this subset selectively expanded in survivors of severe cases and subsided before discharge, but such transient expansion was not observed in non-survivors in Japanese cohort. Analysis of plasma cytokine/chemokine levels revealed positive correlation of PMN-MDSC frequencies with interleukin 8 (IL-8) levels prior to the cell expansion, indicating the involvement of IL-8 on recruitment of PMN-MDSCs to peripheral blood following the onset of severe COVID-19. Thus, our data indicates that transient expansion of the PMN-MDSC subset results in improved clinical outcome. Thus, this myeloid cell subset may be a predictor of prognosis in cases of severe COVID-19 in Japan.

Study of the K_{L}→π^{0}νν[over ¯] Decay at the J-PARC KOTO Experiment

The rare decay K_{L}→π^{0}νν[over ¯] was studied with the dataset taken at the J-PARC KOTO experiment in 2016, 2017, and 2018. With a single event sensitivity of (7.20±0.05_{stat}±0.66_{syst})×10^{-10}, three candidate events were observed in the signal region. After unveiling them, contaminations from K^{±} and scattered K_{L} decays were studied, and the total number of background events was estimated to be 1.22±0.26. We conclude that the number of observed events is statistically consistent with the background expectation. For this dataset, we set an upper limit of 4.9×10^{-9} on the branching fraction of K_{L}→π^{0}νν[over ¯] at the 90% confidence level.

Air Quality Response in China Linked to the 2019 Novel Coronavirus (COVID-19) Lockdown

Efforts to stem the spread of COVID-19 in China hinged on severe restrictions to human movement starting 23 January 2020 in Wuhan and subsequently to other provinces. Here, we quantify the ancillary impacts on air pollution and human health using inverse emissions estimates based on multiple satellite observations. We find that Chinese NOx emissions were reduced by 36% from early January to mid-February, with more than 80% of reductions occurring after their respective lockdown in most provinces. The reduced precursor emissions increased surface ozone by up to 16 ppb over northern China but decreased PM2.5 by up to 23 μg m-3 nationwide. Changes in human exposure are associated with about 2,100 more ozone-related and at least 60,000 fewer PM2.5-related morbidity incidences, primarily from asthma cases, thereby augmenting efforts to reduce hospital admissions and alleviate negative impacts from potential delayed treatments.

Efficacy of PD-1 Inhibitors in Older Non-small Cell Lung Cancer Patients

BACKGROUND/AIM

We assessed the efficacy of immune checkpoint inhibitors (ICIs) in older patients because of the limited information regarding these patients.

PATIENTS AND METHODS

We retrospectively analyzed 66 consecutive patients ≥70 years old with advanced non-small cell lung cancer (NSCLC). A total of 31 patients received ICIs (ICIs group) and 35 patients received only cytotoxic regimens (No ICIs group).

RESULTS

Patients with squamous cell carcinoma who received ICIs had better overall survival (OS) than those who did not (9.7 versus 4.7 months, p=0.027). In multivariate analysis, treatment with ICIs [hazard ratio (HR)=0.54, 95% confidence interval (CI)=0.30-0.98, p=0.044], good performance status (HR=0.30, 95%CI=0.16-0.57, p=0.0003), and histology other than squamous cell carcinoma (HR=0.41, 95%CI=0.19-0.83, p=0.014) were significantly favorable factors for OS.

CONCLUSION

ICIs may be effective for older patients with NSCLC, especially squamous cell carcinoma patients.

Search for K_{L}→π^{0}νν[over ¯] and K_{L}→π^{0}X^{0} Decays at the J-PARC KOTO Experiment

A search for the rare decay K_{L}→π^{0}νν[over ¯] was performed. With the data collected in 2015, corresponding to 2.2×10^{19} protons on target, a single event sensitivity of (1.30±0.01_{stat}±0.14_{syst})×10^{-9} was achieved and no candidate events were observed. We set an upper limit of 3.0×10^{-9} for the branching fraction of K_{L}→π^{0}νν[over ¯] at the 90% confidence level (C.L.), which improved the previous limit by almost an order of magnitude. An upper limit for K_{L}→π^{0}X^{0} was also set as 2.4×10^{-9} at the 90% C.L., where X^{0} is an invisible boson with a mass of 135  MeV/c^{2}.

Balance of Emission and Dynamical Controls on Ozone During the Korea-United States Air Quality Campaign From Multiconstituent Satellite Data Assimilation

Global multiconstituent concentration and emission fields obtained from the assimilation of the satellite retrievals of ozone, CO, NO2, HNO3, and SO2 from the Ozone Monitoring Instrument (OMI), Global Ozone Monitoring Experiment 2, Measurements of Pollution in the Troposphere, Microwave Limb Sounder, and Atmospheric Infrared Sounder (AIRS)/OMI are used to understand the processes controlling air pollution during the Korea-United States Air Quality (KORUS-AQ) campaign. Estimated emissions in South Korea were 0.42 Tg N for NO x and 1.1 Tg CO for CO, which were 40% and 83% higher, respectively, than the a priori bottom-up inventories, and increased mean ozone concentration by up to 7.5 ± 1.6 ppbv. The observed boundary layer ozone exceeded 90 ppbv over Seoul under stagnant phases, whereas it was approximately 60 ppbv during dynamical conditions given equivalent emissions. Chemical reanalysis showed that mean ozone concentration was persistently higher over Seoul (75.10 ± 7.6 ppbv) than the broader KORUS-AQ domain (70.5 ± 9.2 ppbv) at 700 hPa. Large bias reductions (>75%) in the free tropospheric OH show that multiple-species assimilation is critical for balanced tropospheric chemistry analysis and emissions. The assimilation performance was dependent on the particular phase. While the evaluation of data assimilation fields shows an improved agreement with aircraft measurements in ozone (to less than 5 ppbv biases), CO, NO2, SO2, PAN, and OH profiles, lower tropospheric ozone analysis error was largest at stagnant conditions, whereas the model errors were mostly removed by data assimilation under dynamic weather conditions. Assimilation of new AIRS/OMI ozone profiles allowed for additional error reductions, especially under dynamic weather conditions. Our results show the important balance of dynamics and emissions both on pollution and the chemical assimilation system performance.

Comparison of the efficacies of first-generation epidermal growth factor receptor tyrosine kinase inhibitors for brain metastasis in patients with advanced non-small-cell lung cancer harboring EGFR mutations

BACKGROUND

Compared with standard chemotherapy, epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are more effective in patients with advanced non-small-cell lung cancer (NSCLC) harboring EGFR mutations. However, data comparing the efficacies of different EGFR-TKIs, especially regarding the presence of brain metastasis, are lacking.

METHODS

EGFR-TKI naive patients with recurrent or stage IIIB/IV NSCLC harboring EGFR mutations, excluding resistance mutations, were enrolled in this study. We retrospectively determined progression-free survival (PFS) using the Kaplan-Meier method with log-rank test in patients treated with either gefitinib or erlotinib, cumulative incidence of central nervous system (CNS) progression using the Fine and Gray competing risk regression model, and favorable prognostic factors for CNS progression by multivariate analysis.

RESULTS

Seventy-seven EGFR-TKI-naive patients were started on either gefitinib (n = 55) or erlotinib (n = 22) in our hospital from April 2010 to April 2016. Among the patients with brain metastasis, PFS tended to be longer in the erlotinib than in the gefitinib group. In the analysis of cumulative incidence, the probability of CNS progression was lower in the erlotinib group than in the gefitinib group. Particularly, in a subgroup analysis of the patients with brain metastasis, there was a significant difference between the erlotinib and gefitinib groups (hazard ratio 0.25; 95% confidence interval, 0.08-0.81; p = 0.021). Of the prognostic factors for CNS progression evaluated, the absence of brain metastasis before EGFR-TKI therapy and receiving erlotinib (vs gefitinib) had a significantly favorable effect on patient prognosis.

CONCLUSION

Although this was a retrospective analysis involving a small sample size, erlotinib is potentially more promising than gefitinib for treatment of brain metastasis in patients with EGFR-mutant NSCLC.

Bifidobacterium bifidum YIT 10347 fermented milk exerts beneficial effects on gastrointestinal discomfort and symptoms in healthy adults: A double-blind, randomized, placebo-controlled study

In a preliminary open-label trial by our group, Bifidobacterium bifidum YIT 10347 (YIT10347) relieved gastric symptoms in patients with functional gastrointestinal disorders. Hence, in this study, we investigated the effects of YIT10347 on gastrointestinal symptoms in healthy adults. In this prospective double-blind, randomized, placebo-controlled trial (UMIN000024654), 100 healthy Japanese adults were randomly assigned to a YIT10347 group or placebo group and consumed 100 mL of YIT10347-fermented milk or placebo fermented milk, respectively, every day for 4 wk. Gastrointestinal symptoms were evaluated by using the modified Frequency Scale for Symptoms of Gastroesophageal Reflux Disease (m-FSSG) and Gastrointestinal Symptom Rating Scale (GSRS) as primary endpoints. Mental symptoms, quality of life, salivary stress markers, and gastric emptying were evaluated as secondary endpoints. Effectiveness and safety were analyzed in a per-protocol set (YIT10347 group, n = 39; placebo group, n = 40) and full analysis set (YIT10347 group, n = 50; placebo group, n = 50), respectively. In the m-FSSG evaluation, the YIT10347 group had a significantly higher relief rate of postprandial discomfort and greater changes in postprandial epigastric pain score from baseline than the placebo group. In the GSRS evaluation, the YIT10347 group had significantly higher relief rates of overall gastrointestinal symptoms, upper gastrointestinal symptoms, flatus, and diarrhea than the placebo group. We detected no significant differences in scores or relief rates of mental symptoms and quality of life, a salivary stress marker, or gastric emptying between the 2 groups. No severe adverse events associated with test beverage consumption were observed in either group. These findings suggest that daily consumption of YIT10347-fermented milk exerts beneficial effects on gastrointestinal discomfort and symptoms such as postprandial discomfort and epigastric pain in healthy adults.

Effects of fermented soymilk with Lactobacillus casei Shirota on skin condition and the gut microbiota: a randomised clinical pilot trial

Several clinical studies have shown that isoflavones and Lactobacillus casei Shirota (LcS) have beneficial effects on skin condition and the gut microbiota, respectively. Thus, we investigated the effects of consecutive intake of fermented soymilk (FSM) with LcS on skin condition and the gut microbiota, as well as isoflavone bioavailability, in a randomised, double-blind, placebo-controlled trial as a pilot study. Sixty healthy premenopausal Japanese women received FSM containing a moderate level of isoflavone aglycones and a probiotic LcS, or soymilk (SM) containing neither of them, twice a day for 8 weeks. Skin condition was assessed by a subjective questionnaire for face and morphological analysis of the stratum corneum on the inner forearm. Faecal microbiota and urinary isoflavone were analysed by 16S rRNA gene amplicon sequencing and high-performance liquid chromatography tandem mass spectrometry, respectively. Both the FSM and SM groups had improved skin condition as assessed from scores of overall satisfaction, dryness, moisture, elasticity, coarseness, pigmentation and/or stratum corneum morphology, as well as significantly increased levels of urinary isoflavones during the intake period compared with the pre-intake period, although there were no significant differences between the two groups. There was a significant positive correlation between urinary isoflavone levels and skin questionnaire scores. In contrast, the relative abundance levels of Lactobacillaceae significantly increased and those of Bifidobacteriaceae tended to increase during the intake period compared with the pre-intake period. For the after-intake period they only decreased significantly in the FSM group. The levels of Enterobacteriaceae and Porphyromonadaceae significantly decreased during the intake period in the FSM group. These findings suggest that daily intake of FSM, as well as SM, provides health benefits that improve skin condition via increased levels of isoflavone absorption in the body, and that only FSM beneficially modifies the gut microbiota in premenopausal healthy women.

Intracellular GSH of Streptococcus thermophilus shows anti-oxidative activity against low-density lipoprotein oxidation in vitro and in a hyperlipidaemic hamster model

Streptococcus thermophilus YIT 2001 (ST-1), a lactic acid bacterial strain, was shown to have inhibitory effects on the oxidation of low-density lipoprotein (LDL) and the development of aortic fatty lesions in an animal model, and lower the serum levels of malondialdehyde-modified LDL, an oxidative modification product of LDL, in a clinical trial. This study aimed to identify the intracellular active component of ST-1 associated with anti-oxidative activity against LDL oxidation. High-performance liquid chromatography-electrospray ionisation mass spectrometry analysis after fractionation of the cellular extract by reversed-phase chromatography demonstrated that the active fraction contained reduced glutathione (GSH). GSH showed anti-oxidative activity in a dose-dependent manner, while this activity disappeared following thiol derivatisation. ST-1 had the strongest anti-oxidative activity against LDL oxidation and the highest level of intracellular GSH among five strains of S. thermophilus. In addition, the anti-oxidative activity of ST-1 after thiol derivatisation decreased by about half, which was similar to that of three other strains containing poor or no intracellular GSH or thiol components. Moreover, anti-oxidative activity against LDL oxidation was observed in hyperlipidaemic hamsters fed with high GSH ST-1 cells but not in those given low GSH cells. These findings suggest that intracellular GSH in ST-1 may provide beneficial effects via anti-oxidative activity against LDL oxidation and excess oxidative stress in the blood.

Beneficial effects of Lactobacillus casei strain Shirota on academic stress-induced sleep disturbance in healthy adults: a double-blind, randomised, placebo-controlled trial

The present study examined whether Lactobacillus casei strain Shirota (LcS) improves sleep quality under psychological stress. A double-blind, placebo-controlled trial was conducted in healthy 4^th year medical students exposed to academic examination stress. The trial was repeated over two consecutive years in different groups of students, and the data were pooled. For 8 weeks prior to and 3 weeks after a national standardised examination, a total of 48 and 46 subjects received a daily dose of 100 ml of LcS-fermented milk or non-fermented placebo milk, respectively. Study measures included subjective anxiety, overnight single-channel electroencephalography (EEG) recordings, and the Oguri-Shirakawa-Azumi (OSA) sleep inventory scores of subjective sleep quality. Total OSA scores were significantly lower than baseline on the day before the exam and recovered after the exam, indicating a stress-induced decline in sleep quality. There was a significant positive effect of LcS treatment on OSA factors for sleepiness on rising and sleep length. Sleep latency measured by EEG lengthened as the exam approached in the placebo group but was significantly suppressed in the LcS group. The percentage of stage 3 non-REM (N3) sleep decreased in the placebo group as the exam approached, whereas it was maintained in the LcS group throughout the trial. Delta power during the first sleep cycle, measured as an index of sleep intensity, increased as the exam approached in the LcS group and was significantly higher than in the placebo group. These findings suggest that daily consumption of LcS may help to maintain sleep quality during a period of increasing stress. The observed retention of N3 sleep and increased delta power in the LcS group may have contributed to higher perceived sleep satisfaction.