Association between Smoking Status and Obesity in a Nationwide Survey of Japanese Adults

Objective

A positive association between the number of cigarettes smoked per day and obesity has been reported, whereas how other smoking-related indices, such as pack-years and duration of smoking, are related with obesity has been less investigated. We analyzed the age-adjusted cross-sectional association between smoking and obesity in a general Japanese population.

Methods

We used data from a nationwide epidemiological study of Japanese adults (N = 23,106). We compared the prevalence of obesity (defined as body mass index ≥ 25kg/m²) among groups classified by smoking behavior, pack-years, number of cigarettes per day, duration of smoking, and duration and time of smoking cessation.

Results

In men, current smokers had a lower odds ratio (OR) for obesity of 0.80 (95% confidence interval (CI): 0.72–0.88) compared to non-smokers, whereas past smokers had a higher OR of 1.23 (95% CI: 1.09–1.37) compared to current smokers. In women, there were no differences in obesity between the three groups classified by smoking behavior. However, in both sexes, the prevalence of obesity tended to increase with pack-years and the number of cigarettes per day, but not with duration of smoking in current and past smokers. Further, in male smokers, the risks for obesity were markedly higher in short-term heavy smokers compared with long-term light smokers, even with the same number of pack-years. Regarding the impact of smoking cessation, female past smokers who quit smoking at an age > 55-years had an elevated OR of 1.60 (95% CI:1.05–2.38) for obesity.

Conclusions

In a general Japanese population, obesity is progressively associated with pack-years and number of cigarettes per day, but not with the duration of smoking. When investigating the association between obesity and cigarette smoking, the daily smoking burden and the duration of smoking require to be independently considered.     

Nondestructive evaluation of photosynthesis by delayed luminescence in Arabidopsis in Petri dishes

Nondestructive evaluation of photosynthesis is a valuable tool in the field and laboratory. Delayed luminescence (DL) can reflect charge recombination through the backflow of electrons. However, DL detection has not yet been adapted for whole plants in Petri dishes. To compensate for differences in DL decay between sibling Arabidopsis plants grown under the same conditions, we developed a time-sequential double measurement method. Using this method, we examined the influence of photosynthetic electron flow inhibitors, and differences in the DL decay curves were categorized by considering the initial and late phases of the decay curves, as well as their intermediate slopes. The appearance of concavity and convexity in DL curves in Arabidopsis was different from unicellular algae, suggesting complexity in the photosynthetic machinery of higher plants. This detection method should be invaluable for evaluating photosynthetic defects in higher plants under sterile conditions without interrupting plant culture.     

FOXO1 delays skeletal muscle regeneration and suppresses myoblast proliferation

Unloading stress, such as bed rest, inhibits the regenerative potential of skeletal muscles; however, the underlying mechanisms remain largely unknown. FOXO1 expression, which induces the upregulated expression of the cell cycle inhibitors p57 and Gadd45α, is known to be increased in the skeletal muscle under unloading conditions. However, there is no report addressing FOXO1-induced inhibition of myoblast proliferation. Therefore, we induced muscle injury by cardiotoxin in transgenic mice overexpressing FOXO1 in the skeletal muscle (FOXO1-Tg mice) and observed regeneration delay in skeletal muscle mass and cross-sectional area in FOXO1-Tg mice. Increased p57 and Gadd45α mRNA levels, and decreased proliferation capacity were observed in C2C12 myoblasts expressing a tamoxifen-inducible active form of FOXO1. These results suggest that decreased proliferation capacity of myoblasts by FOXO1 disrupts skeletal muscle regeneration under FOXO1-increased conditions, such as unloading.     

Uptake of infant and preschool immunisations in Scotland and England during the COVID-19 pandemic: An observational study of routinely collected data

BackgroundIn 2020, the SARS-CoV-2 (COVID-19) pandemic and lockdown control measures threatened to disrupt routine childhood immunisation programmes with early reports suggesting uptake would fall. In response, public health bodies in Scotland and England collected national data for childhood immunisations on a weekly or monthly basis to allow for rapid analysis of trends. The aim of this study was to use these data to assess the impact of different phases of the pandemic on infant and preschool immunisation uptake rates.Methods and findingsWe conducted an observational study using routinely collected data for the year prior to the pandemic (2019) and immediately before (22 January to March 2020), during (23 March to 26 July), and after (27 July to 4 October) the first UK “lockdown”. Data were obtained for Scotland from the Public Health Scotland “COVID19 wider impacts on the health care system” dashboard and for England from ImmForm.Five vaccinations delivered at different ages were evaluated; 3 doses of “6-in-1” diphtheria, tetanus, pertussis, polio, Haemophilus influenzae type b, and hepatitis B vaccine (DTaP/IPV/Hib/HepB) and 2 doses of measles, mumps, and rubella (MMR) vaccine. This represented 439,754 invitations to be vaccinated in Scotland and 4.1 million for England. Uptake during the 2020 periods was compared to the previous year (2019) using binary logistic regression analysis. For Scotland, uptake within 4 weeks of a child becoming eligible by age was analysed along with geographical region and indices of deprivation. For Scotland and England, we assessed whether immunisations were up-to-date at approximately 6 months (all doses 6-in-1) and 16 to 18 months (first MMR) of age.We found that uptake within 4 weeks of eligibility in Scotland for all the 5 vaccines was higher during lockdown than in 2019. Differences ranged from 1.3% for first dose 6-in-1 vaccine (95.3 versus 94%, odds ratio [OR] compared to 2019 1.28, 95% confidence intervals [CIs] 1.18 to 1.39) to 14.3% for second MMR dose (66.1 versus 51.8%, OR compared to 2019 1.8, 95% CI 1.74 to 1.87). Significant increases in uptake were seen across all deprivation levels.In England, fewer children due to receive their immunisations during the lockdown period were up to date at 6 months (6-in-1) or 18 months (first dose MMR). The fall in percentage uptake ranged from 0.5% for first 6-in-1 (95.8 versus 96.3%, OR compared to 2019 0.89, 95% CI 0.86– to 0.91) to 2.1% for third 6-in-1 (86.6 versus 88.7%, OR compared to 2019 0.82, 95% CI 0.81 to 0.83).The use of routinely collected data used in this study was a limiting factor as detailed information on potential confounding factors were not available and we were unable to eliminate the possibility of seasonal trends in immunisation uptake.ConclusionsIn this study, we observed that the national lockdown in Scotland was associated with an increase in timely childhood immunisation uptake; however, in England, uptake fell slightly. Reasons for the improved uptake in Scotland may include active measures taken to promote immunisation at local and national levels during this period and should be explored further. Promoting immunisation uptake and addressing potential vaccine hesitancy is particularly important given the ongoing pandemic and COVID-19 vaccination campaigns.

Fiona McQuaid and colleagues assess the uptake of infant and pre-school immunisations in Scotland and England during the COVID-19 pandemic.     

Species diversity in native fish community in Japan: comparison between non-invaded and invaded ponds by exotic fish

The relationship between invasions by two exotic fishes (Micropterus salmoides and Lepomis macrochirus) and species diversity in native fish communities was studied in 14 Japanese farm ponds. We found that mean number of species in native fish communities was three times higher in the ponds without the exotic fish than in the ponds with them. Further, negative relationships were observed between abundance of the two exotic fish and the total abundance of native fish communities. Our results suggest that invasions by the two exotic fish caused serious depletion of native fish communities, although another process can also be considered , that is, that ponds with poor native fish communities were prone to colonization by these exotic fish.     

Migration from plant to plant: an important factor controlling densities of the epiphytic cladoceran <Emphasis Type="Italic">Alona</Emphasis> (Chydoridae,Anomopoda) on lake vegetation

We investigated seasonal changes in the density of epiphytic cladocerans Alona spp. (Chydoridae, Anomopoda) in two habitats, emergent and submerged aquatic plants, in Lake Suwa, Japan, from April to August 1998 and from April to November 2000. Alona had a density peak in early June on reeds (emergent) and in late June on Potamogeton malaianus (submerged). In summer, Alona density remained low in both habitats. Although density was positively correlated with the abundance of epiphytic algae, the birth rate was constant and no correlation between algal abundance and clutch size was detected. In a field experiment using ropes as an artificial substrate covered with high and low densities of epiphytic algae as food, more Alona attached to the ropes with the high density of algae. These results suggest that Alona may select food-rich habitats and migrate seasonally, and that migration is an important factor in the population dynamics of epiphytic chydorid cladocerans such as Alona. In Lake Suwa, Alona may migrate from the reed zone to the submerged macrophyte zone in June.     

Comparison of HIV-1 nef and gag Variations and Host HLA Characteristics as Determinants of Disease Progression among HIV-1 Vertically Infected Kenyan Children

Objectives

Disease progression varies among HIV-1-infected individuals. The present study aimed to explore possible viral and host factors affecting disease progression in HIV-1-infected children.

Methods

Since 2000, 102 HIV-1 vertically-infected children have been followed-up in Kenya. Here we studied 29 children (15 male/14 female) who started antiretroviral treatment at <5 years of age (rapid progressors; RP), and 32 (17 male/15 female) who started at >10 years of age (slow progressors; SP). Sequence variations in the HIV-1 gag and nef genes and the HLA class I-related epitopes were compared between the two groups.

Results

Based on nef sequences, HIV-1 subtypes A1/D were detected in 62.5%/12.5% of RP and 66.7%/20% of SP, with no significant difference in subtype distribution between groups (p = 0.8). In the ten Nef functional domains, only the PxxP₃ region showed significantly greater variation in RP (33.3%) than SP (7.7%, p = 0.048). Gag sequences did not significantly differ between groups. The reportedly protective HLA-A alleles, A*74:01, A*32:01 and A*26, were more commonly observed in SP (50.0%) than RP (11.1%, p = 0.010), whereas the reportedly disease-susceptible HLA-B*45:01 was more common in RP (33.3%) than SP (7.4%, p = 0.045). Compared to RP, SP showed a significantly higher median number of predicted HLA-B-related 12-mer epitopes in Nef (3 vs. 2, p = 0.037), HLA-B-related 11-mer epitopes in Gag (2 vs. 1, p = 0.029), and HLA-A-related 9-mer epitopes in Gag (4 vs. 1, p = 0.051). SP also had fewer HLA-C-related epitopes in Nef (median 4 vs. 5, p = 0.046) and HLA-C-related 11-mer epitopes in Gag (median 1 vs. 1.5, p = 0.044) than RP.

Conclusions

Compared to rapid progressors, slow progressors had more protective HLA-A alleles and more HLA-B-related epitopes in both the Nef and Gag proteins. These results suggest that the host factor HLA plays a stronger role in disease progression than the Nef and Gag sequence variations in HIV-1-infected Kenyan children.