University of Niigata Prefecture

Objectives The aim of this study was to analyze the association between employment status, family structure, and nutrient adequacy in working-age Japanese adults (aged 20-64 years).Methods Data from the 2019 National Health and Nutrition Survey and the Comprehensive Survey of Living Conditions, conducted by the Ministry of Health, Labour and Welfare, were used to examine the associations between nutrient adequacy and employment status (full-time, part-time, unemployed, or not applicable) and family structure (single, couple only, two-parents and child [parent, child], single parent and child [parent, child], three-generations [parent, child], and other family structures). Logistic regression analysis was performed with nutrient deficiency as the dependent variable and employment status and family structure as independent variables, controlling for age, municipality size, and prefecture of residence.Results The association between employment status and nutrient adequacy, as assessed by the chi-squared test, showed statistically significant differences in the percentage of nutrient inadequacy across employment status categories among women for three nutrients, but not among men. The chi-squared test between family structure and nutrient adequacy showed statistically significant differences for 10 nutrients for men and 14 nutrients for women. Among men, parents in three-generation families had higher inadequacy rates; among women, those living alone showed higher inadequacy rates. Logistic regression revealed that, compared with those in full-time employment, men in part-time employment had statistically higher inadequacy in total fiber, folic acid, potassium, and magnesium. For women, employment status was associated with inadequacy of n-6 fatty acids, total fiber, vitamin A, vitamin C, salt equivalents, and magnesium. Furthermore, nutrient inadequacy differed significantly by family structure for 14 nutrients in men and 16 nutrients in women. For men, single individuals, and parents in three-generation families showed statistically higher inadequacy rates for some nutrients, while for women, of the 16 nutrients showing statistically significant differences, children in "two-parent and child families" and women in "couple-only families" showed lower rates of nutrient inadequacy for 9 and 8 nutrients, respectively.Conclusion Nutritional disparities among working-age adults are associated with employment patterns and family structure. In addition, nutrient excesses and deficiencies were identified in groups previously overlooked, such as parents in two-parent and child households and three-generation households, highlighting the need for policies that address these diverse factors.

While the contributions of labor and productivity to agriculture have been extensively studied, agricultural investment and capital accumulation remain underexplored. This gap is largely due to a lack of relevant data, particularly in developing countries. In China, measuring agricultural investment poses significant challenges due to a complex statistical system and frequent changes in official data standards, especially before 1978. This study aimed to construct a comprehensive dataset on agricultural investment from 1952 to 2017, encompassing state-owned, collective, and household agriculture. To ensure consistency and reliability, different estimation methods were applied according to the data sources available in different periods. The analysis revealed that while collective farming was the dominant model before 1978, a substantial share of investment was directed toward state-owned agriculture. After the reform era, the introduction of the household responsibility system led to a surge in household agricultural investment, primarily funded through self-accumulation. However, by 2010, the share of government appropriations and agricultural loans began to decline, with non-household entities accounting for 50% of total agricultural investment. This shift indicates a move away from direct investment by peasant households toward service-oriented agricultural production. Investment in China’s agricultural sector exhibits significant cyclical patterns, influenced by economic policies and labor dynamics. Given recent challenges in food self-sufficiency and declining agricultural labor, reassessing agricultural investment levels is crucial for ensuring sustainable development.

BackgroundSeasonal influenza continues to pose a significant global public health challenge owing to its considerable disease burden, making it imperative to elucidate its potential driving factors. Although the roles of meteorological factors such as temperature and absolute humidity have been extensively investigated, research quantifying the burden of ambient ozone (O₃) as an environmental determinant of influenza, particularly among vulnerable populations, remains limited. The aims of this study were to assess short-term effects of photochemical oxidants (Ox, parts per billion [ppb]) in a temperate Japanese city, quantify the associated attributable burden, and evaluate variations across subgroups to enhance understanding and identify high-risk populations.MethodsDaily time-series data on influenza cases, photochemical Ox levels, and meteorological factors were compiled for Kawasaki City, Japan, spanning 2015 to 2019. Using time-stratified case-crossover analyses and a distributed lag non-linear model, Ox–influenza associations were evaluated, accounting for long-term trends, seasonality, and day-of-the-week effects, and capturing both non-linear and delayed impacts. The overall attributable fractions (AFs) and those corresponding to low and high Ox levels were subsequently calculated. Furthermore, subgroup analyses were conducted according to influenza subtype, sex, and age group.ResultsData of 163,120 influenza cases were analyzed. Overall, a U-shaped exposure–response curve was observed between Ox concentrations and influenza incidence. The overall minimum morbidity Ox (MMOx) level was 48.4 ppb (94.0%), with cumulative relative risks of 2.06 (95% confidence interval [CI]: 1.50, 2.82) and 1.47 (95% CI: 0.78, 1.51) observed at low and high Ox levels, respectively. The burden of influenza incidence attributable to non-optimal MMOx level was estimated at 36.6% (95% empirical CI: 17.1, 50.9), with the majority of this burden arising from low Ox concentrations. Furthermore, patients with influenza A exhibited higher risks and AFs than did patients with influenza B, although the differences by sex and age group were not statistically significant.ConclusionsOverall, non-optimal photochemical Ox levels are associated with a substantial burden of influenza morbidity. These findings may inform local public health initiatives by aiding the development of targeted preparedness and prevention strategies to mitigate short-term effects of air pollution.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12889-025-24755-0.

Background: Long-term inhibition of the renin-angiotensin system (RAS) causes hyperactivation and phenotypic changes of renin cells, resulting in hypertrophy of the renal afferent arterioles. However, the impact of this arteriolar hypertrophy on renal function remains unclear. Atrial natriuretic peptide (ANP) suppresses renin secretion, yet its potential to counteract arteriolar hypertrophy has not been explored. Methods: A novel mouse model of afferent arteriolar hypertrophy was established by long-term administration of an angiotensin II receptor blocker (ARB) in wild-type C57BL/6NJ mice. To evaluate the functional impact, mice were assigned to three groups: control (vehicle), ARB (valsartan), and angiotensin receptor–neprilysin inhibitor (ARNI; sacubitril/valsartan). All treatments were administrated via oral gavage for 24 weeks. To investigate ANP’s effects on renin cells, we used As4.1 cells, a mouse-derived renin-expressing cell line. Cells were treated with ANP, a natriuretic peptide (NP) receptor antagonist, or a combination of both, followed by assessment of renin expression. Results: After 24 weeks, the ARB group exhibited elevated blood urea nitrogen and serum cystatin C levels compared to the controls, along with marked afferent arteriolar hypertrophy and cortical fibrosis on renal histology. In the ARNI group, plasma ANP levels were significantly higher than in the ARB group, despite comparable blood pressure levels. Although arteriolar hypertrophy was also observed in the ARNI group, the arteriolar diameter was significantly smaller than in the ARB group. Furthermore, the ARNI group showed reduced renin expression and secretion, improved renal function, lower injury marker levels, and attenuated cortical fibrosis compared to the ARB group. In As4.1 cells, ANP significantly suppressed renin expression, and this effect was abolished by co-treatment with the NP receptor antagonist. Conclusion: Chronic inhibition of RAS can cause renal dysfunction with afferent arteriolar hypertrophy. ANP suppresses renin cell activation through NP receptor signaling. Neprilysin inhibition, which increases circulating ANP levels, attenuates renin cell activation and arteriolar hypertrophy, thereby offering potential renoprotective effects.

BackgroundWhile the oral glucose tolerance test (OGTT) is the gold standard for diagnosing gestational diabetes mellitus (GDM), hemoglobin A1c (A1C), glycated albumin (GA), and fructosamine (Fruc) have the potential to conveniently classify pregnant women as having or not having GDM because two or more measurements are not necessary, unlike with OGTT. Compared with A1C, GA or Fruc, which reflects more recent glycemic indices, may more accurately detect GDM. This meta-analysis compared the diagnostic ability of GDM between GA or Fruc and A1C.MethodComprehensive literature searches were performed for studies published up to Sep.11, 2023. Selected studies were limited to those that attempted to identify GDM using both GA and/or Fruc and A1C to compare these indicators. Two authors extracted the data. Disagreements were resolved by a third author. Study quality was assessed by a revised tool for quality assessment of diagnostic accuracy in studies (QUADUS-2). The dataset consisting of true-positives, false-positives, false-negatives, and true-negatives was pooled with a bivariate between-study model and hierarchical summary receiver operating characteristic model. Pooled relative sensitivity and specificity based on a random-effects model were calculated to compare the diagnostic ability of A1C and GA and/or Fruc for GDM.ResultThere were 20 eligible studies. Pooled positive and negative likelihood ratios with 95% confidence intervals (CI) were 5.11 (2.30–11.37) and 0.53 (0.40–0.71), respectively, if GA or Fruc was used and 3.75 (2.61–11.39) and 0.53 (0.42–0.66), respectively, if A1C was used. Relative sensitivity and specificity (95% CI) for GA or Fruc compared with A1C was 1.00 (0.94–1.07) and 0.99 (0.97–1.01), respectively.ConclusionThe insufficiently low value of the negative likelihood ratio did not support the single use of GA/Fruc or A1C in screening for GDM suggesting the necessity of combining other risk factors with glycemic indicators. Although there was no statistically significant difference in diagnostic ability between GA or Fruc and A1C, the value of the positive likelihood ratio indicated that GA or Fruc was somewhat more useful than A1C as a rule-in test for the diagnosis of GDM.Systematic review registrationPROSPERO CRD42023461975.

ABSTRACTThe coronavirus disease 2019 (COVID‐19) pandemic required face masks to be worn in public spaces, changing daily face‐to‐face communication. This study investigated whether infants perceived masked faces as faces during the COVID‐19 pandemic, a time when wearing masks in public was nearly universal in Japan. Between July 2021 and November 2022, we conducted an experiment using a novel remote method to examine infants' preferences for upright versus inverted faces under both masked and unmasked conditions. Overall, infants aged 4–5 months and 7–8 months (n = 32 in each age group) preferred upright to inverted faces in both conditions. These results suggest that Japanese infants born during the COVID‐19 pandemic could recognize masked faces as faces. Furthermore, across both age groups, the preference was more pronounced in the masked‐face condition than in the unmasked‐face condition. These results possibly reflect the fact that infants had relatively frequent exposure to masked faces during the pandemic.

We investigated whether rice protein ameliorates the osteoporosis associated with type 2 diabetes in Zucker diabetic fatty rats. Diets containing rice endosperm protein, rice bran protein, or casein were fed for 10 weeks. The rats exhibited an early stage of diabetic nephropathy and chronic kidney disease–mineral and bone disorder, and parameters reflecting mineral and bone metabolism and bone structure and strength were evaluated. Feeding casein to Zucker Diabetic Fatty rats increased their serum fibroblast growth factor 23 and parathyroid hormone concentrations, suggesting relative excess phosphorus intake, a low serum osteocalcin concentration, and a slightly elevated serum tartrate-resistant acid phosphatase-5b concentration, indicating bone catabolism. In addition, the microarchitecture and strength of the femur were impaired. However, feeding rice endosperm protein and rice bran protein improved these parameters to near normal. These results imply that feeding these rice proteins causes an amelioration of diabetic osteoporosis.

ABSTRACT This article compares two methods for detecting local item dependence (LID): residual correlation examination and Rasch testlet modeling (RTM), in a commonly used 3:6 matching format and an extended matching test (EMT) format. The two formats are hypothesized to facilitate different levels of item dependency due to differences in the number of options and instructions regarding option recycling. The findings indicate that (1) RTM allows deeper LID inspection compared to residual correlation examination in matching tests, and (2) the EMT format has good resistance to LID while the traditional 3:6 format does not.