Characterization of Influenza A(H1N1)pdm09 Viruses Isolated in the 2018-2019 and 2019-2020 Influenza Seasons in Japan.

The influenza A(H1N1)pdm09 virus that emerged in 2009 causes seasonal epidemic worldwide. The virus acquired several amino acid substitutions that were responsible for antigenic drift until the 2018-2019 influenza season. Viruses possessing mutations in the NA and PA proteins that cause reduced susceptibility to NA inhibitors and baloxavir marboxil, respectively, have been detected after antiviral treatment, albeit infrequently. Here, we analyzed HA, NA, and PA sequences derived from A(H1N1)pdm09 viruses that were isolated during the 2018-2019 and 2019-2020 influenza seasons in Japan. We found that A(H1N1)pdm09 viruses possessing the D187A and Q189E substitutions in HA emerged and dominated during the 2019-2020 season; these substitutions in the antigenic site Sb, a high potency neutralizing antibody-eliciting site for humans, changed the antigenicity of A(H1N1)pdm09 viruses. Furthermore, we found that isolates possessing the N156K substitution, which was predicted to affect the antigenicity of A(H1N1)pdm09 virus at the laboratory level, were detected at a frequency of 1.0% in the 2018-2019 season but 10.1% in the 2019-2020 season. These findings indicate that two kinds of antigenically drifted viruses-N156K and D187A/Q189E viruses-co-circulated during the 2019-2020 influenza season in Japan.

A Nationwide Antenatal Human T-Cell Leukemia Virus Type-1 Antibody Screening in Japan.

Japan has been running a nationwide antenatal human T-cell leukemia virus type-1 (HTLV-1) antibody screening program since 2010 for the prevention of HTLV-1 mother-to-child transmission. As part of the program, pregnant women are invited to take an HTLV-1 antibody screening test, usually within the first 30 weeks of gestation, during regular pregnancy checkups. Pregnant women tested positive on the antibody screening test undergo a confirmatory test, either western blotting or line immunoassay. In indeterminate case, polymerase chain reaction (PCR) is used as a final test to diagnose infection. Pregnant women tested positive on a confirmatory or PCR test are identified as HTLV-1 carriers. As breastfeeding is a predominant route of postnatal HTLV-1 mother-to-child transmission, exclusive formula feeding is widely used as a postnatal preventive measure. Although there is insufficient evidence that short-term breastfeeding during ≤3 months does not increase the risk of mother-to-child transmission compared to exclusive formula feeding, this feeding method is considered if the mother is eager to breastfeed her child. However, it is important that mothers and family members fully understand that there is an increase in the risk of mother-to-child transmission when breastfeeding would be prolonged. As there are only a few clinical studies on the protective effect of frozen-thawed breastmilk feeding on mother-to-child transmission of HTLV-1, there is little evidence to recommend this feeding method. Further study on the protective effects of these feeding methods are needed. It is assumed that the risk of anxiety or depression may increase in the mothers who selected exclusive formula feeding or short-term breastfeeding. Thus, an adequate support and counseling for these mothers should be provided. In addition to raising public awareness of HTLV-1 infection, epidemiological data from the nationwide program needs to be collected and analyzed. In most cases, infected children are asymptomatic, and it is necessary to clarify how these children should be followed medically.

Antigenic variants of influenza B viruses isolated in Japan during the 2017-2018 and 2018-2019 influenza seasons.

BACKGROUND: Here, we genetically and antigenically analyzed influenza B viruses (IBVs) isolated in Japan during the 2017-2018 and 2018-2019 influenza seasons. METHODS: A total of 68 IBVs (61 B/Yamagata/16/88-like [B/Yamagata]-lineage and 7 B/Victoria/2/87-like [B/Victoria]-lineage) were antigenically and genetically characterized by using hemagglutination inhibition (HI) assays and phylogenetic analysis, respectively. The susceptibility of IBVs to neuraminidase (NA) inhibitors was assessed by using a fluorescence-based NA inhibition assay. RESULTS: All 61 B/Yamagata-lineage isolates were genetically closely related to B/Phuket/3073/2013, the vaccine strain for these two seasons. Eleven B/Yamagata-lineage isolates tested were antigenically similar to B/Phuket/3073/2013 by the HI test. Seven B/Victoria-lineage isolates were genetically closely related to B/Texas/02/2013, the WHO-recommended vaccine strain for the 2017-2018 season; however, they were antigenically distinct from B/Texas/02/2013 with an eightfold or 16-fold difference in HI titer. Of these 7 isolates, 4 possessed a two-amino-acid deletion at positions 162 and 163 in hemagglutinin (HA) and the other 3 had a three-amino-acid deletion at positions 162-164 in HA. Importantly, the variants with the three-amino-acid deletion appeared to be antigenically different from the B/Colorado/06/2017 virus with the two-amino-acid deletion, the vaccine strain for the 2018-2019 season with a fourfold or eightfold difference in HI titer. One B/Yamagata-lineage isolate carrying a G407S mutation in its NA showed a marked reduction in susceptibility to zanamivir, peramivir, and laninamivir. CONCLUSIONS: These results highlight the need for continued monitoring for the prevalence of the antigenic variant with the three-amino-acid deletion and the variant with reduced NA inhibitor susceptibility.

Influenza A variants with reduced susceptibility to baloxavir isolated from Japanese patients are fit and transmit through respiratory droplets.

Here we report the isolation of the influenza A/H1N1 2009 pandemic (A/H1N1pdm) and A/H3N2 viruses carrying an I38T mutation in the polymerase acidic protein-a mutation that confers reduced susceptibility to baloxavir marboxil-from patients before and after treatment with baloxavir marboxil in Japan. These variants showed replicative abilities and pathogenicity that is similar to those of wild-type isolates in hamsters; they also transmitted efficiently between ferrets by respiratory droplets.

Physiologic Leg Bowing is not a Physiologic Condition but Instead is Associated with Vitamin D Disorders in Toddlers.

When children around 2-year-old show leg bowing without lower-limb radiographic abnormalities for rickets, the leg bowing is classified as "physiologic" genu varum without conducting a blood test. However, it has recently been suggested that toddlers who are diagnosed with physiologic genu varum may in fact have some form of bone metabolic disorder. In this 1:2 case-control study, blood samples were obtained from 33 toddlers with genu varum without radiographic abnormalities for rickets and 66 age- and gender-matched healthy children. Serum alkaline phosphatase (sALP), intact parathyroid hormone (siPTH), 25-hydroxy vitamin D [s25(OH)D], calcium (sCa), and inorganic phosphate (sP) were measured. s25(OH)D of the subjects with genu varum (24.8 ng/ml) were significantly lower than those of the control (33.6 ng/ml) (p < 0.001). The frequency of vitamin D insufficiency/deficiency (< 20 ng/ml) of the subjects with genu varum (39%) was significantly higher than that in the control (14%) (p = 0.004) (odds ratio by vitamin D insufficiency/deficiency: 4.1 [1.5-11.1, p = 0.004]). sCa in subjects with genu varum (10.2 ng/ml) were significantly higher than in control (9.8 ng/ml) (p < 0.001), as were sALP (1057 IU/l) and siPTH (28.4 pg/ml) (740 IU/l and 8.8 pg/ml in control, respectively; p < 0.001). siPTH levels were associated with s25(OH)D levels in subjects with genu varum (r = - 0.57, p < 0.001), while no association was observed in the control (r = 0.11, p = 0.36). Genu varum without radiographic abnormalities of rickets was associated with both vitamin D and bone-metabolic disorders in toddlers, indicating that physiologic genu varum is not a physiologic condition in toddlers.

The increase in bone mineral density by bisphosphonate with active vitamin D analog is associated with the serum calcium level within the reference interval in postmenopausal osteoporosis.

OBJECTIVES: To examine the factors associated with increase in lumbar spine bone mineral density (LS-BMD) by bisphosphonates (BPs) with active vitamin D analog (aVD). METHODS: Two independent postmenopausal osteoporotic patients treated by BPs with aVD for 24 months (Study 1: n = 93, Study 2: n = 99) were retrospectively analyzed. RESULTS: In Study 1, LS-BMD of the patients significantly increased for 24 m (5.4%, p < .001). A multiple regression analysis among baseline characteristics revealed that serum calcium (sCa: 8.5-10.5 mg/dL) was associated with an increased LS-BMD by treatment (r2: 0.088, p = .02). While average sCa of the patients was 9.2 mg/dL before treatment, it increased time-dependently to 9.6 mg/dL for 24 m by treatment. As each patient had their LS-BMD five times during the study, there were four instances of %LS-BMD in each patient, resulting in 372 instances of %LS-BMD in Study 1. The smallest Akaike's information criterion value for the most appropriate cut-off levels of sCa for %LS-BMD by treatment every 6 m was 9.3 mg/dL. The %LS-BMD by treatment for 6 m during 24 m period in patients with sCa ≥9.3 mg/dL (1.5%) was significantly higher than that in patients with sCa <9.3 mg/dL (0.8%, p = .038). The results of Study 2 were similar to those of Study 1, confirming the phenomena observed. CONCLUSION: sCa was associated with an increased LS-BMD by BPs with aVD.

Current Vitamin D Status in Healthy Japanese Infants and Young Children.

This study aimed to characterize serum 25-hydroxyvitamin D (25OH-D) values among Japanese children aged ≤48 mo. The study included 290 healthy infants and young children aged 0-48 mo (males/females=166/124) living in Shizuoka or Tokyo. The subjects were divided into three groups by age (Low Age: 0-5, Middle Age: 6-15, High Age: 16-48 mo). The vitamin D deficient state was defined as 25OH-D <12 ng/mL, the insufficient state as 12-20 ng/mL, and the sufficient state as >20 ng/mL. The seasonal variation of serum 25OH-D levels was also analyzed. The median serum 25OH-D levels in each group were: Low Age (n=50), 19 ng/mL; Middle Age (n=94), 30 ng/mL; and High Age (n=146), 30 ng/mL. The serum 25OH-D level was significantly lower in the Low Age group than in the other groups (p<0.01). Serum 25OH-D levels in summer and autumn (n=149) were significantly higher than in winter and spring (n=141) (33 vs. 25 ng/mL, p<0.01). In the Low Age group, there was a significant difference in serum 25OH-D levels between breast-fed infants (n=26) and formula-fed or mixed-fed infants (n=19) (12 vs. 32 ng/mL, p<0.01). However, there were no significant differences in 25OH-D levels between the two season classifications in either breast-fed or formula-fed and mixed-fed infants. Although clinical symptoms were not available, more than 75% of the breast-fed infants and 14.6% of infants and young children to whom food had been introduced were defined as having a vitamin D deficient or insufficient state. Breastfeeding seems one of the contributing factor to lower serum 25 OH-D levels among infants ≤5 mo of age.

Association between leg bowing and serum alkaline phosphatase level regardless of the presence of a radiographic growth plate abnormality in pediatric patients with genu varum.

When children around 2 years of age show leg bowing and diseases are ruled out based on radiographic findings without conducting blood tests, they are classified as "physiologic" genu varum. Since whether or not physiologic genu varum is associated with bone metabolism is unclear, this study was conducted to clarify the association between genu varum and bone metabolism in children. Thirty-five pediatric patients with genu varm who visited our out-patient clinic were enrolled. While two of the 35 children had nutritional rickets, showing abnormalities on both blood test (ALP, ≥1000 IU/L; iPTH, >65 pg/mL and 25(OH)D, ≤20 ng/mL) and radiographs (such as cupping, fraying or splaying), five of 35 children showed abnormalities on blood tests but not radiographs. While metaphyseal-diaphyseal angle (MDA) correlated with serum 25-hydroxy vitamin D (r = -0.35, p = 0.04) and magnesium (r = -0.36, p = 0.04), MDA and femorotibial angle (FTA) correlated with alkaline phosphatase (r = 0.43, p = 0.01 and r = 0.51, p = 0.006, respectively). A ridge regression analysis adjusted for age and body mass index indicated that ALP was associated with MDA and FTA. A logistic regression analysis adjusted for age and BMI indicated that higher ALP influenced an MDA >11°, which indicates the risk for the progression of genu varum (odds ratio 1.002, 95% confidence interval 1.0003-1.003, p = 0.021). The higher ALP (+100 IU), the higher risk of an MDA >11° (odds ratio 1.22). In conclusion, genu varum is associated with the alkaline phosphatase level regardless of the presence of radiographic abnormalities in the growth plate in children.

Prophylaxis for ribavirin-related anemia using eicosapentaenoic acid in chronic hepatitis C patients.

BACKGROUND: Ribavirin-related anemia is a serious side-effect of the pegylated interferon and ribavirin therapy used for hepatitis C, and may be cause for a reduction in ribavirin dose or even cessation of treatment. The aim of this study was to evaluate the prophylactic effects of oral eicosapentaenoic acid (EPA) supplementation on ribavirin-induced hemolytic anemia in pediatric and young adult patients. METHODS: Twelve chronic hepatitis C patients ranging in age from 3 to 21 years (mean, 13.9 ± 5.1 years) who received pegylated interferon α-2b and ribavirin combination therapy were randomized to either the control group (n = 6) or EPA group (n = 6). Blood samples were collected before, and at 4, 8, and 16 weeks after treatment to measure clinical laboratory parameters. RESULTS: The reduction in hemoglobin levels of the EPA group was significantly ameliorated at 8 and 16 weeks when compared to the control group (P < 0.05). There was no significant difference in plasma ribavirin concentrations between the two groups during the treatment. However, one patient in the control group had a reduction in ribavirin dose. CONCLUSION: EPA supplementation prevented ribavirin-induced hemolytic anemia during combination therapy with pegylated interferon α-2b and ribavirin in pediatric and young adult patients.

Minimum required vitamin D level for optimal increase in bone mineral density with alendronate treatment in osteoporotic women.

Vitamin D insufficiency and deficiency are common in the elderly. Most previous studies using alendronate have used vitamin D supplementation regardless of individual vitamin D status. However, the minimum required vitamin D levels for the efficacy of alendronate treatment of osteoporosis remain unclear. Fifty-two postmenopausal women, diagnosed with osteoporosis, were enrolled in this prospective study, in which they took 5 mg of alendronate daily for 6 months without any supplements. Associations between baseline factors and their changes during the treatment and the change in the lumbar spine bone mineral density (LS-BMD) were examined. The most appropriate cut-off level of 25-hydroxyvitamin D (25[OH]D) for the optimal increase in LS-BMD with alendronate was determined using the Akaike information criterion statistical criterion. Overall, alendronate treatment significantly increased LS-BMD by 4.7%. The basal serum 25(OH)D and change in urinary NTX were significantly associated with the increase in LS-BMD. The increase in LS-BMD between the two groups was not different when comparing those with baseline 25(OH)D above vs. below 30 ng/ml. However, 25(OH)D of 25 ng/ml was determined to be the minimum required vitamin D level for an adequate effect of alendronate. Vitamin D status may affect the increase in LS-BMD with alendronate treatment in individuals being treated for osteoporosis, and a 25(OH)D level >25 ng/ml appears to be required for an optimal LS-BMD response.

Association of oestrogen receptor gene polymorphism with the long-term results of rotational acetabular osteotomy.

Acetabular dysplasia (AD) contributes to the development of osteoarthritis of the hip. A rotational acetabular osteotomy (RAO) is one of the methods of pelvic osteotomy to prevent or treat secondary osteoarthritis of the hip. Although most of the patients that undergo RAO show satisfactory results, some have poor results. This study investigated whether gene polymorphisms of both the vitamin D receptor (VDR) and oestrogen receptor (ER) are involved in both AD and the postoperative results following RAOs. Sixty-four Japanese patients with AD who were treated by an RAO were enrolled in this study (59 women and 5 men, aged 13-59, with an average age of 40.3). Gene polymorphisms of the VDR [ApaI and TaqI restriction fragment length polymorphisms (RFLPs)] and ER (PvuII and XbaI RFLPs) were determined in these patients. The relationship between both the AD and radiographic postoperative changes of the hip joint after an RAO with these gene polymorphisms were examined. The frequencies of ER gene polymorphism coded as pp (RFLP/PvuII) in patients with AD were statistically significantly different (p = .011) from those coded as both PP and Pp. The joint space width narrowed even after RAO in 90% of the patients with the pp gene polymorphism, while it narrowed in only 35% of the patients with either PP or Pp seven years or longer after an RAO. The PvuII polymorphism in the ER gene was associated with the postoperative result of an RAO, while no association was observed between the AD with VDR and ER gene polymorphisms.

Bone mineral density in children and adolescent girls with anorexia nervosa in Japan.

BACKGROUND: The correlation between reduced bone mineral density (BMD) and the disease anorexia nervosa (AN) has long been established. The aim of the present study was to examine the relationship in more detail, particularly focusing on the increasing incidence of the disease occurring in adolescent patients. METHOD: Twenty-four girls diagnosed with AN were enrolled in the study. All subjects ranged in age from 11.1 to 15.5 years, with an average age of 13.5 years. The BMD of lumbar spines and femoral necks were measured. All the values for BMD at admission were expressed as means +/- SD and patients with and without menarche were separately investigated. RESULTS: The average BMD of lumbar spines at the time of admission was -0.51 SD in total. However, the average BMD of patients without menarche was -1.28 SD, which was significantly lower than the -0.16 SD on average in patients with menarche. As a whole the BMD of femoral necks at admission tended to be lower than that of lumbar spines. Similarly, it was lower in patients without menarche (-1.7 SD on average) than in those with menarche (-0.77 SD on average). CONCLUSIONS: BMD was lower in children and adolescent AN patients without menarche, and such a tendency was more significant at the femoral neck region. In child AN cases without menarche, the BMD, especially at the femoral neck, needs to be measured, and later recovery should be monitored closely over a long period.

Serum free T4 and thyroid stimulating hormone levels in preterm infants and relationship between these levels and respiratory distress syndrome.

BACKGROUND: There have been few studies of the thyroid stimulating hormone (TSH) surge in extremely low-birthweight (ELBW) infants, and the relationship between thyroid hormones and respiratory distress syndrome (RDS) has yet to be clarified. The present study sought to determine the serum levels of free T4 (fT4) and TSH in ELBW infants and to examine the relationship between these levels and the development of RDS. METHODS: The authors measured serum fT4 and TSH levels soon after birth in 449 preterm infants, who were born at 22-36 weeks of gestation, and determined the associations between these levels, the incidence of RDS, and the recognized clinical factors associated with RDS. RESULTS: Serum fT4 and TSH levels, and the fT4/TSH ratio, in the group at 22-24 weeks of gestation were significantly lower than those in the group at 28-36 weeks. The levels and ratio increased significantly with increasing gestational age. There were significant correlations between the serum fT4 level and the birthweight, Apgar score, and gender, and between the serum TSH level and the gestational age, mode of delivery, and birthweight. No significant relationship between the incidence of RDS and the serum levels of fT4 and TSH was observed. CONCLUSION: The authors' results suggest that the serum levels of fT4 and TSH in ELBW infants are very low, and that these levels are not correlated with the occurrence of RDS.

TRRAP as a hepatic coactivator of LXR and FXR function.

TBP-free TAF II-containing-type HAT complex subclasses, which contain hGCN5 HAT and TRRAP, appear to act as common coactivator complexes for nuclear receptors. However, their physiological significance with respect to each nuclear receptor remains to be established. To address this issue, we used hepatic cell lines (HepG2) with reduced endogenous TRRAP expression through antisense RNA expression or with overexpressed TRRAP or other major coactivators. The ligand-induced transactivation function of liver X receptor alpha (LXRalpha) and farnesoid X receptor/bile acid receptor reflected TRRAP expression levels, while that of PPARgamma did not. A GST pull-down assay indicated that TRRAP contains two potential LXRalpha-interacting domains in the C-terminal and central domains. Expression of antisense TRRAP RNA in HepG2 cells abolished the ligand-induced expression of LXRalpha target genes. These results suggested that TRRAP plays an important role as a coactivator, presumably part of a complex, in lipid metabolism through regulation of the LXRalpha-mediated gene cascade in hepatic cells.

Association of bone mineral density with vitamin D and estrogen receptor gene polymorphisms during GnRH agonist treatment.

AIMS: This study examined whether or not a decrease in bone mineral density (BMD) induced by the use of gonadotropin-releasing hormone agonist (GnRHa) during sexual maturation is affected by vitamin D receptor and/or estrogen receptor gene polymorphisms, like the phenomenon observed during the postmenopausal period. METHODS: In 43 patients who received GnRHa therapy for 6 months to treat uterine myoma or endometriosis at our department and who were confirmed to have pituitary down-regulation, we measured bone density before and after GnRHa treatment using DXA and analyzed the bone metabolism turnover using bone metabolic markers. Polymorphisms were analyzed by RFLP using FokI and TaqI for the vitamin D receptor gene and PvuII and XbaI for the estrogen receptor gene. The then determined gene polymorphism was analyzed in relation to the percentage decreases in BMD following GnRHa treatment. RESULTS: The patients were divided by f, t into two groups: (f, t) < 2 (Group V-I) and (f, t) > or = 2 (Group V-II). They were also divided by P, x into two groups (P, x) < 3 (Group E-I) and (P, x) > or = 3 (Group E-II). The BMD change was significantly higher in Group V-II than in Group V-I. Group E-II tended to have a higher BMD change than Group E-I, although this difference was not statistically significant. CONCLUSION: Patients who often have f and t polymorphism are more likely to show BMD reduction following GnRHa therapy, like the phenomenon seen during the postmenopausal period, than patients with other gene polymorphisms. Measures to avoid BMD reduction are required when using GnRHa in such patients.

The chromatin-remodeling complex WINAC targets a nuclear receptor to promoters and is impaired in Williams syndrome.

We identified a human multiprotein complex (WINAC) that directly interacts with the vitamin D receptor (VDR) through the Williams syndrome transcription factor (WSTF). WINAC has ATP-dependent chromatin-remodeling activity and contains both SWI/SNF components and DNA replication-related factors. The latter might explain a WINAC requirement for normal S phase progression. WINAC mediates the recruitment of unliganded VDR to VDR target sites in promoters, while subsequent binding of coregulators requires ligand binding. This recruitment order exemplifies that an interaction of a sequence-specific regulator with a chromatin-remodeling complex can organize nucleosomal arrays at specific local sites in order to make promoters accessible for coregulators. Furthermore, overexpression of WSTF could restore the impaired recruitment of VDR to vitamin D regulated promoters in fibroblasts from Williams syndrome patients. This suggests that WINAC dysfunction contributes to Williams syndrome, which could therefore be considered, at least in part, a chromatin-remodeling factor disease.

[Genetic factors of osteoporosis and polymorphisms].

Osteoporosis is a common disease with a strong genetic factors. Twin studies have shown that genetic factors play an important role in regulating bone turnover and bone mineral density. These phenotypes are determined by the combined effects of several genes and environmental influences. A great deal of research has been done on candidate genes, among the best studied are vitamin D receptor gene. From a clinical standpoint, advances in knowledge about the prospect of developing genetic markers for the assessment of fracture risk will be used as targets for the design of new drugs for the prevention and treatment of osteoporosis.

[Dietary calcium and VDR gene polymorphism's interaction].

The fundamental role of vitamin D receptor (VDR) gene polymorphisms have been reviewed. The VDR gene polymorphisms are associated with the intestinal calcium absorption , rate of bone gain and loss. The observed variability in younger and elderly people in the response of bone mass to calcium intake and supplementation may be explained partly by the interaction between environmental and genetic factors.