A growing number of diseases in humans, including trauma, certain cancers, and infection, are known to be associated with l-arginine deficiency. In addition, l-arginine must be supplemented by diet during pregnancy to aid fetal development. In conditions of l-arginine depletion, T cell proliferation is impaired. We have previously shown that neonatal blood has lower l-arginine levels than adult blood, which is associated with poor neonatal lymphocyte proliferation, and that l-arginine enhances neonatal lymphocyte proliferation through an interleukin (IL)-2-independent pathway. In this study, we have further investigated how exogenous l-arginine enhances neonatal regulatory T-cells (Tregs) function in relation to IL-10 production under epigenetic regulation. Results showed that cord blood mononuclear cells (CBMCs) produced higher levels of IL-10 than adult peripheral blood mononuclear cells (PBMCs) by phytohemagglutinin stimulation but not by anti-CD3/anti-CD28 stimulation. Addition of exogenous l-arginine had no effect on transforming growth factor-β production by PBMCs or CBMCs, but enhanced IL-10 production by neonatal CD4⁺CD25⁺FoxP3⁺ Tregs. Further studies showed that IL-10 promoter DNA hypomethylation, rather than histone modification, corresponded to the l-arginine-induced increase in IL-10 production by neonatal CD4⁺ T cells. These results suggest that l-arginine modulates neonatal Tregs through the regulation of IL-10 promoter DNA methylation. l-arginine supplementation may correct the Treg function in newborns with l-arginine deficiency.

In the real world, dynamic changes in air pollutants and meteorological factors coexist simultaneously. Studies identifying the effects of individual pollutants on acute exacerbation (AE) of asthma may overlook the health effects of the overall combination. A comprehensive study examining the influence of air pollution and meteorological factors is required. Asthma AE data from emergency room visits were collected from the Taiwan National Health Insurance Research Database. Complete monitoring data for air pollutants (SO₂; NO₂; O₃; CO; PM_2.5; PM₁₀) and meteorological factors were collected from the Environmental Protection Agency monitoring stations. A bi-directional case-crossover analysis was used to investigate the effects of air pollution and meteorological factors on asthma AE. Among age group divisions, a 1 °C temperature increase was a protective factor for asthma ER visits with OR = 0.981 (95% CI, 0.971–0.991) and 0.985 (95% CI, 0.975–0.994) for pediatric and adult patients, respectively. Children, especially younger females, are more susceptible to asthma AE due to the effects of outdoor air pollution than adults. Meteorological factors are important modulators for asthma AE in both asthmatic children and adults. When studying the effects of air pollution on asthma AE, meteorological factors should be considered.

The objective of this study is to compare the chromosomal distribution of early miscarriages with or without embryonic poles. It was a retrospective study of 223 women who underwent dilation and curettage (D&C) between 1995 and 2013 for early miscarriages. The presence or absence of a fetal pole was evaluated by abdominal or transvaginal ultrasound. Cytogenetic tests of products of conception following culture were determined in both groups. Of the 223 early miscarriages, 143 had embryos and 80 did not. The abnormality rate differed significantly (61.5 % vs. 46.3 %, p < 0.05), with trisomy 18, 21 and 45X found only in miscarriages with embryos. There were no significant differences between groups in rates of triploidy, tetraploidy, mosaicism, structure and double abnormality. The female abortus rate was higher in miscarriages with or without embryonic poles, as well as in groups with normal and abnormal karyotypes. Chromosome distribution differs in miscarriages with or without embryonic poles. The ultrasound findings might offer different direction to determine the causes of early miscarriages. The higher female abortus rate may be associated with early selection.

In cases of arginine depletion, lymphocyte proliferation, cytokine production and CD3ζ chain expression are all diminished. In addition to myeloid suppressor cells, polymorphonuclear cells (PMN) also exert T‐cell immune suppressive effects through arginase‐induced l‐arginine depletion, especially during pregnancy. In this study, we investigated how arginase/l‐arginine modulates neonatal lymphocyte proliferation. Results showed that the neonatal plasma l‐arginine level was lower than in adults (48·1 ± 11·3 versus 86·5 ± 14·6 μm; P = 0·003). Neonatal PMN had a greater abundance of arginase I protein than adult PMN. Both transcriptional regulation and post‐transcriptional regulation were responsible for the higher arginase I expression of neonatal PMN. Exogenous l‐arginine enhanced neonate lymphocyte proliferation but not that of adult cells. The RNA‐binding protein HuR was important but was not the only modulation factor in l‐arginine‐regulated neonatal T‐cell proliferation. l‐Arginine‐mediated neonatal lymphocyte proliferation could not be blocked by interleukin‐2 receptor blocking antibodies. These results suggest that the altered arginase/l‐arginine cascade may be one of the mechanisms that contribute to altered neonatal immune responses. Exogenous l‐arginine could enhance neonate lymphocyte proliferation through an interleukin‐2‐independent pathway.