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Abstract The low response rate of immune checkpoint inhibitors (ICIs) is a challenge. The efficacy of ICIs is influenced by the tumour microenvironment, which is controlled by the gut microbiota. In particular, intestinal bacteria and their metabolites, such as short chain fatty acids (SCFAs), are important regulators of cancer immunity; however, our knowledge on the effects of individual SCFAs remains limited. Here, we show that isobutyric acid has the strongest effect among SCFAs on both immune activity and tumour growth. In vitro, cancer cell numbers were suppressed by approximately 75% in humans and mice compared with those in controls. Oral administration of isobutyric acid to carcinoma-bearing mice enhanced the effect of anti-PD-1 immunotherapy, reducing tumour volume by approximately 80% and 60% compared with those in the control group and anti-PD-1 antibody alone group, respectively. Taken together, these findings may support the development of novel cancer therapies that can improve the response rate to ICIs.

The centrosome is a major microtubule organizing center in animal cells. The position of the centrosomes inside the cell is important for cell functions such as cell cycle, and thus should be tightly regulated. Theoretical models based on the forces generated along the microtubules have been proposed to account for the dynamic movements of the centrosomes during the cell cycle. These models, however, often adopted inconsistent assumptions to explain distinct but successive movements, thus preventing a unified model for centrosome positioning. For the centration of the centrosomes, weak attachment of the astral microtubules to the cell cortex was assumed. In contrast, for the separation of the centrosomes during spindle elongation, strong attachment was assumed. Here, we mathematically analyzed these processes at steady state and found that the different assumptions are proper for each process. We experimentally validated our conclusion using nematode and sea urchin embryos by manipulating their shapes. Our results suggest the existence of a molecular mechanism that converts the cortical attachment from weak to strong during the transition from centrosome centration to spindle elongation.

Abstract Corticosteroids use in coronavirus disease 2019 (COVID-19) is controversial, especially in mild to severe patients who do not require invasive/noninvasive ventilation. Moreover, many factors remain unclear regarding the appropriate use of corticosteroids for COVID-19. In this context, this multicenter, retrospective, propensity score–matched study was launched to evaluate the efficacy of systemic corticosteroid administration for hospitalized patients with COVID-19 ranging in the degree of severity from mild to critically-ill disease. This multicenter, retrospective study enrolled consecutive hospitalized COVID-19 patients diagnosed January–April 2020 across 30 institutions in Japan. Clinical outcomes were compared for COVID-19 patients who received or did not receive corticosteroids, after adjusting for propensity scores. The primary endpoint was the odds ratio (OR) for improvement on a 7-point ordinal score on Day 15. Of 1092 COVID-19 patients analyzed, 118 patients were assigned to either the corticosteroid and non-corticosteroid group, after propensity score matching. At baseline, most patients did not require invasive/noninvasive ventilation (85.6% corticosteroid group vs. 89.8% non-corticosteroid group). The odds of improvement in a 7-point ordinal score on Day 15 was significantly lower for the corticosteroid versus non-corticosteroid group (OR, 0.611; 95% confidence interval [CI], 0.388–0.962; p = 0.034). The time to improvement in radiological findings was significantly shorter in the corticosteroid versus non-corticosteroid group (hazard ratio [HR], 1.758; 95% CI, 1.323–2.337; p

This study explored how foreign language anxiety in class relates to individualism-collectivism culture. Additionally, to serve as a guideline for foreign language anxiety assessment, the study determined a normative score of the Foreign Language Classroom Anxiety Scale (FLCAS), which is well known and frequently applied for foreign language anxiety examination. After conducting a literature search identifying 106 studies in 35 countries/regions, a top-down approach was used to analyze aggregate FLCAS mean scores by country/region and examine relationships between the FLCAS score and the rating of individualism-collectivism cultural dimension from Hofstede’s cultural index. This relationship was significant for higher education institutions but insignificant for all institutions and for elementary to high schools. The FLCAS normative score was 94.82, slightly lower than the theoretical midpoint of 99. The findings have implications for educators, since university/college/graduate students in countries/regions with stronger collectivism had higher foreign language anxiety.

Experimental studies have developed, conducted, and evaluated classroom interventions for foreign language anxiety (FLA) reduction. However, various characteristics of those classroom interventions make it difficult to synthesize the findings and apply them to practice. We conducted what is, to the best of our knowledge, the first systematic review on educational interventions for FLA. Six criteria were established for inclusion of studies. Using English keywords, we identified 854 potentially eligible studies through ProQuest and Scopus, 40 of which were finally included. All included studies were published from 2007 to 2020. The studies differed in type of intervention, duration of intervention, and scale to measure FLA. Our systematic review resulted in seven features of classroom interventions, categorized as student–student interactions, student-teacher interactions, self-management, and mood boosters; we also categorized interventions as either individual or interactional.

This study had two aims: to attempt to verify the construct validity of the measure of international posture—which refers to attitudes toward the international community—in foreign language education and to explore how international posture structurally relates to personality traits. A total of 163 Japanese undergraduate students participated in the study. To examine the first aim, exploratory factor analysis was conducted, followed by confirmatory factor analysis. Results of the exploratory factor analysis showed that three latent constructs were extracted from 23 items of the measure. Next, confirmatory factor analysis confirmed the constructs with the fit indices except the chi-square score. To investigate the second aim, structural equation modeling was used. It showed that two personality traits—openness to experience and extraversion—were strongly associated with international posture. Furthermore, our study indicated a second-order configuration structured in the verified measure in relation to the two personality traits.

Abstract This study aimed to investigate the latent constructs in the Foreign Language Classroom Anxiety Scale using a research context of Japanese undergraduates who learn English as a foreign language. The study conducted both exploratory and confirmatory factor analysis against two different groups of Japanese undergraduate students. First, exploratory factor analysis was used to extract factors from 33 items of the scale in its application to 149 management major students. Subsequently, confirmatory factor analysis was conducted on the factors from the exploratory factor analysis. Data from 237 English language learners at two universities—155 undergraduates at a foreign study university and 82 at a general university—were applied to test a hypothetical model in relation to the extracted latent constructs. Results of the two factor analyses identified and confirmed two underlying components of the scale: (1) communication apprehension and (2) fear of failing. The model fit statistics illustrated that the two-factor paradigm appropriately fit the data from the second undergraduate group. Implications of the results are discussed.

Inhibition of macrophage apoptosis by Mycobacterium tuberculosis has been proposed as one of the virulence mechanisms whereby the pathogen avoids the host defense. The mechanisms by which M. tuberculosis H37Rv strain suppress apoptosis and escapes human macrophage killing was investigated.The screening of a transposon mutant bank identified several mutants, which, in contrast to the wild-type bacterium, had impaired ability to inhibit apoptosis of macrophages. Among the identified genes, Rv3659c (31G12 mutant) belongs to an operon reminiscent of type IV pili. The Rv3654c and Rv3655c putative proteins in a seven-gene operon are secreted into the macrophage cytoplasm and suppress apoptosis by blocking the extrinsic pathway. The operon is highly expressed when the bacterium is within macrophages, compared to the expression level in the extracellular environment. Rv3654c recognizes the polypyrimidine tract binding Protein-associated Splicing Factor (PSF) and cleaves it, diminishing the availability of caspase-8. While M. tuberculosis inhibits apoptosis by the extrinsic pathway, the pathogen does not appear to affect the intrinsic pathway. Inactivation of the intrinsic pathway by pharmacologic agents afftects M. tuberculosis and induces cell necrosis. Likewise, inactivation of PSF by siRNA significantly decreased the level of caspase-8 in macrophages.While M. tuberculosis inhibits the extrinsic pathway of apoptosis, it appears to activate the intrinsic pathway leading to macrophage necrosis as a potential exit strategy.

Caffeine (CFF) is efficiently absorbed after ingestion, and approximately 80% of ingested CFF is metabolized to paraxanthine (PXT). Although PXT has approximately twice the adenosine receptor antagonist activity of CFF, there are few reports measuring the metabolite concentrations during CFF intoxication. Furthermore, no studies have examined the efficacy of hemodialysis (HD) on PXT or the indicators that contribute to treatment strategies for patients with acute CFF intoxication. This study analyzed the association between CFF and PXT blood levels, the blood biochemical data, and the vital signs of 27 cases with information on CFF intake and elapsed time data. It was found that HD was not as effective as CFF against PXT in CFF intoxication; however, HD was effective in cases with relatively high PXT concentrations (>10 μg/mL). Simultaneous analysis of CFF and PXT would make it possible to estimate the time elapsed from CFF intake and the risk of hyperCKemia, which may develop in cases left untreated for a prolonged period after ingestion. Therefore, the measurement of PXT, in addition to CFF, is expected to provide useful information for understanding the pathogenesis of CFF intoxication and the development of treatment strategies of acute CFF intoxication. [ABSTRACT FROM AUTHOR]

Methylmercury (MeHg), a potent neurotoxin, poses substantial risks to prenatal brain development by crossing the placental barrier. In our daily lives, we are exposed to various environmental metals simultaneously with MeHg. Therefore, the combined exposure effects of these metals and MeHg should be investigated. Hence, this study examined the combined fetal exposure effects of MeHg and copper (Cu), an essential element. Gene expression changes in the fetal brains of mice exposed to MeHg, Cu, or both were examined through RNA-seq analysis. Our results showed that the number of variable genes exposed to combined MeHg and Cu increased compared with that in single exposure. Most of them were gene variations specific to combined exposure. Gene Ontology biological process analysis revealed the amplified effects on GABAergic interneurons in the cerebral cortex under combined exposure. IPA pathway analysis indicated considerable variations in pathways related to oxidative stress, neuronal development, and energy metabolism, including the activation of NRF2-mediated oxidative stress response and the suppression of mitochondrial fatty acid beta-oxidation. These findings highlighted the complexity and enhanced risks of combined MeHg and Cu exposure. Therefore, neurodevelopmental effects were more severe and multifaceted than those caused by individual exposures. This research highlighted the importance of understanding the mechanisms of the combined exposure effects of MeHg. [ABSTRACT FROM AUTHOR]

A 76-year-old woman was admitted to the emergency room of Nagano Municipal Hospital with the complain of severe back pain. Chest and abdominal enhanced computed tomography scans showed bilateral adrenal infarction and minute pulmonary nodules, but she had no respiratory symptoms. After admission, a family member of the patient was found to have been in close contact with a coronavirus disease 2019 (COVID-19) patient. Thus, polymerase chain reaction and antigen tests of severe acute respiratory syndrome coronavirus 2 were conducted, and both tests returned positive. D-dimer levels were normal on admission but increased 2 days thereafter. Anticoagulation therapy and steroid replacement were started, and the patient improved over about two weeks. One month after the onset of adrenal infarction, a rapid adrenocorticotropic hormone loading test was conducted, which revealed that the primary adrenal insufficiency due to adrenal infarction might have been caused by the COVID-19 infection. This case was rare and suggestive of adrenal infarction with COVID-19, which usually presents at the severe stage. In patients with COVID-19, attention should be paid to the onset of thrombosis, even with mild respiratory infection. We also suggest that patients with thrombosis should be suspected of having COVID-19 even in the absence of respiratory infectious symptoms in a situation of COVID-19 epidemic. [ABSTRACT FROM AUTHOR]