Associations of sleep problems with asthma and allergic rhinitis among Chinese preschoolers.

The aim of this study was to examine the associations of sleep problems with asthma and allergic rhinitis among Chinese preschoolers. This cross-sectional survey was conducted in Guangzhou, China. Children aged 3-6 years were recruited from 32 kindergartens in 7 administrative districts. Asthma, allergic rhinitis and sleep problems were evaluated using a valid questionnaire. Binary logistic regression models were employed to estimate the odds ratios (OR) and 95% confidence intervals (CI) for the associations of asthma and allergic rhinitis with short sleep duration, late bedtime and frequent nocturnal awakening. We included 4876 preschool children in the current analysis. Of these, 182 (3.7%) diagnosed as asthma, and 511 (10.5%) diagnosed as allergic rhinitis. Frequent nocturnal awakening was associated with asthma and allergic rhinitis, with adjusted OR were 1.49 (95% CI 1.05-2.13) and 1.59 (95% CI 1.27-1.99), respectively. Subgroup analysis showed the OR for frequent nocturnal awakening with asthma was higher in girls (1.68; 95% CI 1.02-2.78) than in boys (1.35; 95% CI 0.81-2.24), but the OR for frequent nocturnal awakening with allergic rhinitis were similar in girls (1.73; 95% CI 1.15-2.30) and boys (1.57; 95% CI 1.17-2.12). No significant associations of short sleep duration and late bedtime with asthma or allergic rhinitis were identified. Our data suggested that frequent nocturnal awakening was associated with asthma and allergic rhinitis among preschoolers, and the association of frequent nocturnal awakening with asthma differed by gender. Further studies are warranted to address the causal relationship between nocturnal awakening and asthma and allergic rhinitis.

Trends in urban/rural inequalities in physical growth among Chinese children over three decades of urbanization in Guangzhou: 1985-2015.

BACKGROUND: Great growth inequalities between urban and rural areas have been reported in China over the past years. By examining urban/rural inequalities in physical growth among children < 7 years old over the past three decades from 1985 to 2015 in Guangzhou, we analyzed altering trends of anthropometric data in children and their association with economic development during the period of rapid urbanization in Guangzhou. METHODS: The height, body weight and nutrition status of children under 7 years old were obtained from two successive cross-sectional surveys and one health surveillance system. Student's t-test, Spearman's rank-order correlation and polynomial regression were used to assess the difference in physical growth between children in urban and rural areas and the association between socioeconomic index and secular growth changes. RESULTS: A height and weight difference was found between urban and rural children aged 0-6 years during the first two decades of our research (1985-2005), which gradually narrowed in both sex groups over time. By the end of 2015, elder boys (age group ≥5 year) and girls (age group ≥4 year) in rural areas were taller than their counterparts in urban areas (p < 0.05).The same trend could be witnessed in the weight of children aged 6 years, with a - 1.30 kg difference (P = 0.03) for boys, and a - 0.05 difference (P = 0.82) for girls. When GDP increased, the gap in boys' weight-for-age z-score (WAZ from 0.25 to 0.01) and height-for-age z-score (HAZ from 0.55 to 0.03) between urban and rural areas diminished, and disappeared when the GDP per capita (USD) approached 25,000. In either urban or rural areas, the urbanization rate and GDP were positively associated with the prevalence of obesity (all R > 0.90 with P < 0.05) and negatively correlated with the prevalence of stunted growth (all R < -0.87 with P < 0.05). CONCLUSION: Growth inequalities gradually decreased with economic development and urbanization, while new challenges such as obesity emerged. To eliminate health problems due to catch-up growth among rural children, comprehensive intervention programs for early child growth should be promoted in rural areas.

[Neuropsychological development of late preterm infants and early term infants at the age of 1 year: a follow-up study].

OBJECTIVE: To study the level of neuropsychological development in late preterm infants and early term infants at the age of 1 year. METHODS: A total of 1 257 children with a corrected age of 1 year were enrolled as subjects. According to gestational age at birth, they were divided into an early preterm group (28-33+6 weeks), a late preterm group (34-36+6 weeks), an early term group (37-38+6 weeks), and a full-term group (39-41+6 weeks). Gesell Developmental Schedules were used to assess the neuropsychological development of the children, and the groups were compared in terms of neuropsychological development at the age of 1 year. RESULTS: There were significant differences in the developmental quotients of the five functional areas (adaptability, gross motor, fine motor, language and social ability) between the four groups at the age of 1 year (P<0.05), and the full-term infants had the highest development quotients, followed by the early term infants, the late preterm infants, and the early preterm infants (P<0.05). The full-term infants had the lowest rate of developmental delay in each functional area, while the early preterm infants had the highest rate (P<0.05). Compared with the full-term infants, the early term infants had a higher risk of developmental delay in adaptability (OR=1.796, P<0.05), and the late preterm infants had a higher risk of developmental delay in adaptability (OR=2.651, P<0.05) and fine motor (OR=2.679, P<0.05), while the early preterm infants had a higher risk of developmental delay in adaptability (OR=4.069, P<0.05), fine motor (OR=3.710, P<0.05), and social ability (OR=3.515, P<0.05). CONCLUSIONS: The risk of neuropsychological developmental delay decreases with the increase in gestational age in children at the age of 1 year, with a dose-response effect. There are varying degrees of developmental delay in early term infants and late preterm infants, and health care follow-up for early term infants and late preterm infants should be taken seriously.

Identification of prognostic biomarkers of prostate cancer with long non-coding RNA-mediated competitive endogenous RNA network.

Prostate cancer (PCa) is the second most frequently diagnosed male cancer, and no treatments exist for effective inhibition of metastatic spread of PCa. Long non-coding RNA (lncRNA) plays key roles in pathogenesis and development of various cancers through competing with endogenous RNAs (ceRNAs), but at present research on lncRNA functions in PCa is still very limited. Hence, this aspect was investigated using bioinformatics methods. Firstly, the functional lncRNA-mediated ceRNA network associated with PCa was constructed by the multi-step computational approach. Then the cytoscape software was used to analyze the node degree and betweenness centrality (BC) value of lncRNAs and mRNAs in the interaction. Finally, the lncRNAs were screened in the central region of the network by the node degree and BC value, and the functional enrichment of mRNAs was evaluated with the Gene Ontology (GO) database. In our results, LINC00476, MALAT1, SNHG11, LINC00649, and ILF3-AS1 are the lncRNAs which have the most nodes and higher BC values and considered as prognostic markers in PCa. GO analysis suggested that the function of screened lncRNAs was obviously focused on intracellular receptor signaling pathway, which indicated these lncRNAs might be potential biomarkers for diagnosis, evaluation and gene-targeted therapy of PCa.

Effectiveness of a Kindergarten-Based Intervention for Preventing Childhood Obesity.

BACKGROUND AND OBJECTIVES: Interventions to prevent childhood obesity targeting school age children have mostly reported limited effectiveness, suggesting such prevention programs may need to start at an earlier age, but evidence has been scarce. We reported a pilot study aiming to demonstrate the feasibility of a multifaceted intervention for preschool children and to provide a preliminary assessment of the effectiveness. METHODS: This nonrandomized controlled trial recruited children aged 3 to 6 years from 6 kindergartens in Guangzhou, China. Based on the preference of the School and Parents Committees, 4 kindergartens (648 children) received a 3-component intervention (training of kindergarten staff, initiating healthy curriculum for children, and close collaboration between families and kindergartens) over 12 months, while the other 2 kindergartens (336 children), serving as controls, received routine health care provision. Outcome measures were the changes in BMI z score between baseline and the end of 12 months, and the prevalence of postintervention children who were overweight or obese. RESULTS: By 12 months, children within the intervention group had a smaller BMI z score increase (0.24) compared to the control (0.41), with a difference of -0.31 (95% CI -0.47 to -0.15). The prevalence of overweight or obesity was also lower among the intervention group at the end of the study (OR: 0.43, 95% CI 0.19 to 0.96), adjusted for baseline status. CONCLUSIONS: Our results indicated a multicomponent health behavior intervention might be effective in reducing the prevalence of obesity, but the longer term effects will need confirmation from randomized controlled trials.

Self-diffusivity, M-S and Fick diffusivity of CO2 in Na-clay: The influences of concentration and temperature.

Storing CO2 in underground saline aquifers is an important way to reduce CO2 emission in atmosphere, where gas/fluid diffusion in clay plays a key role in CO2 leakage and migration. Various diffusivities, self-diffusivity, Maxwell-Stefan (M-S) diffusivity and Fick diffusivity, in clay interlayer are investigated by molecular dynamics (MD). Self-diffusivity varies with CO2 concentration, and reaches the maximum value at 2 molecules/unit-cell. High fluid concentration leads to clay swelling, thereby increasing self-diffusivity. However, the fractional free volume of clay explains the trend of CO2 self-diffusivity, which does not decrease with CO2 concentration monotonously but reaches the maximum when CO2 concentration reaches 2. Displacement distribution of CO2 molecules is analysed to explore the microscopic diffusion mechanism, which is characterised by logarithmic normal distribution. The mean value of such distribution further explains the self-diffusivity dependence on CO2 concentration. M-S and Fick diffusivities of CO2 are calculated by MD for the first time, both of which increase with increasing CO2 and H2O concentration and temperature. Based on self-diffusivity and M-S diffusivity, a quantity representing the coupling strength between CO2 molecules is presented; it increases firstly with CO2 concentration but begins to decrease when CO2 concentration is beyond 2.

The Born in Guangzhou Cohort Study (BIGCS).

The Born in Guangzhou Cohort Study (BIGCS) is a large-scale prospective observational study investigating the role of social, biological and environmental influences on pregnancy and child health and development in an urban setting in southern China. Pregnant women who reside in Guangzhou and who attend Guangzhou Women and Children's Medical Center (GWCMC) for antenatal care in early pregnancy (<20 weeks' gestation) are eligible for inclusion. Study recruitment commenced in February 2012, with an overall participation rate of 76.3%. Study recruitment will continue until December 2018 to achieve the target sample size of 30,000 mother-child pairs. At 30 April 2016, a total of 75,422 questionnaires have been collected, while 14,696 live births have occurred with planned follow-up of cohort children until age 18 years. During the same period a total of 1,053,000 biological samples have been collected from participants, including maternal, paternal and infant blood, cord blood, placenta, umbilical cord, and maternal and infant stool samples. The dataset has been enhanced by record linkage to routine health and administrative records. We plan future record linkage to school enrolment and national examination records.

Optical Nyquist pulse generation using a time lens with spectral slicing.

Optical Nyquist pulse generation based on a time lens with subsequent optical filtering is proposed. A nearly chirp-free 10-GHz 8.1-ps Nyquist pulse generator is experimentally demonstrated. By inserting group velocity dispersion (GVD) between cascaded phase and amplitude modulators, 11 tones ultraflat optical frequency comb (OFC) of 10-GHz frequency spacing within 0.9 dB power variation is obtained. The quasi-rectangular shape spectrum is then filtered out with a tunable rectangular-shaped optical band-pass filter (OBPF) and the quasi-linear chirp is compensated by a segment of standard single mode fiber (SSMF). By changing the wavelength of the continuous wave (CW) light, nearly chirp-free Nyquist pulses over C band are obtained. Furthermore, simultaneous dual-wavelength pulse generation is also demonstrated.

Ultra-flat optical frequency comb generator using a single-driven dual-parallel Mach-Zehnder modulator.

We propose and experimentally demonstrate a simple and cost-effective ultra-flat optical frequency comb (OFC) generator by directly modulating a standalone dual-parallel Mach-Zehnder modulator (DP-MZM) with only one radio frequency (RF) signal without any other assisting devices. Five- and seven-tone OFC with exactly the same intensity can be theoretically generated using two sets of parameters obtained by solving equations derived from the DP-MZM modulation model. In good agreement with the theoretical results, five- and seven-tone OFC with flatness of 0.1 and 1 dB are experimentally demonstrated, respectively.

Gaussian-like dual-wavelength prescaled clock recovery with simultaneous frequency-doubled clock recovery using an optoelectronic oscillator.

A novel multifunctional frequency-doubling optoelectronic oscillator (FD-OEO) mainly based on a Mach-Zehnder modulator (MZM) cascaded with a phase modulator (PM) and a subsequent optical bandpass filter (OBPF) is proposed. We experimentally demonstrate simultaneous operations of frequency-doubled optical clock (FD-OC) recovery, low-duty-cycle dual-wavelength prescaled OC recovery and error-free fourfold time division demultiplexing with the proposed OEO injected with a 4 × 25-Gb/s optical time-division-multiplexing (OTDM) signal. We show that the proposed FD-OEO operates well for both the differential phase shift keying (DPSK) and on-off keying (OOK) modulation formats. The extracted dual-wavelength prescaled OC is proved to be nearly transform-limited with Gaussian-like shape. Furthermore, all four 25-Gb/s tributaries can be selectively demultiplexed by adjusting the phase shifters in the OEO loop. The power penalty at a bit error rate (BER) of 10(-9) is measured to be 2.4 dB, 1.2 dB for the best channel for DPSK signal and to be 2.5 dB, 1.1 dB for the best channel for OOK signal. In addition, as an extra benefit of the OEO, low-phase-noise prescaled electrical clock (EC) is also extracted.

Spontaneous nanoinjection with carbon nanotubes: a molecular dynamics simulation study.

Based on the interactions between the zinc finger protein (ZNF) and single-walled carbon nanotubes (SWCNTs), we design a nanodevice for injecting ZNF spontaneously. The new injection device involves four essential components: a small-diameter SWCNT as a plunger, a large-diameter SWCNT as a tube as well as the nozzle and needle, ZNF and water solution. The injection behavior is demonstrated and analyzed using molecular dynamics simulations. The effects of the diameter, chirality and length of SWCNTs on the injection behavior are analyzed with the center of mass distance, the van der Waals interaction between ZNF and SWCNTs, the root-mean-square deviation of ZNF, and the radius of gyration for ZNF.

Frequency chirp linearization for ultraflat optical frequency comb generation based on group velocity dispersion.

We propose to insert group velocity dispersion between cascaded phase and amplitude modulation for ultraflat optical frequency comb (OFC) generation. With the dispersion, the sinusoidally varied chirp of the continuous wave light induced by phase modulation becomes linear within a relatively wide time interval. This is useful to improve the flatness of the generated OFC by directly cascaded phase and amplitude modulation. Simulation shows a flat comb of 37 tones within 0.88 dB power variation when the modulation index of the phase modulation reaches 20. An ultraflat comb generator with 10 GHz frequency spacing is also demonstrated. The flatness of the 15 tones around the center wavelength has been improved to 0.98 dB.

Effective optical clock recovery and simultaneous fourfold demultiplexing of OTDM signal using an optoelectonic oscillator.

We propose and demonstrate a novel scheme for clock recovery and simultaneous fourfold optical time-division demultiplexing using a dual-parallel Mach-Zehnder modulator based optoelectronic oscillator. 25-GHz prescaled optical clock with a 23% duty cycle and a 22-dB extinction ratio is successfully extracted from both 100-Gb/s on-off keying (OOK) and differential phase-shift keying (DPSK) optical time-division-multiplexing (OTDM) signal. The timing jitters (100 Hz to 10 MHz) are measured to be 195.9 fs and 125.6 fs for the optical clock extracted from the 100-Gb/s OOK and DPSK signal, respectively. Error-free optical time-division demultiplexing is also achieved simultaneously with clock recovery. By adjusting the phase shifter in the OEO loop, all four channels can be selectively demultiplexed. The power penalties at a bit error rate (BER) of 10⁻9 for the four demultiplexed channels are measured to be between 0.8 dB and 1.2 dB for the OOK signal and between 0.9 dB and 1.5 dB for the DPSK signal.

[Epidemiological study on the trend of accidental deaths among children under five in Guangzhou, 2001 - 2010].

OBJECTIVE: To study the trend of accidental death among children under 5 years of age. METHODS: A survey on accidental death among children was performed in Guangzhou to compare the data from the national monitoring program on the deaths under five in the same period during 2001 - 2010. Data on mortality and causes of injures were adjusted by missing reports. RESULTS: Mortality rates on injuries were decreasing annually from 2001 to 2010. Comparing with 2001, the magnitude of the drop in mortality among the 0, 1 - 4 and under 5 year groups were 72.02%, 77.17% and 74.66% respectively, with statistically significant differences (P = 0.000). During the 10 years of observation, data showed a dropping trend (P = 0.000) of the mortalities on drowning, traffic accident, suffocation and falling, especially on drowning and suffocation. The main causes of death were suffocation in the 0 year group, drowning in the 1-2-year group, traffic accident and poisoning in the 3-year group, traffic accident and falling in the 4-year group. The accidental deaths happened in 'C area' which including Huadu, Conghua, Zengcheng, Panyu and Nansha, with the total proportion of accidental death in Guangzhou as 75.69%. CONCLUSION: The mortality of accidental deaths among children under 5 years of age in Guangzhou had been decreasing during 2001 - 2010, mainly owing to the practice of intervention programs on drowning and suffocation, suggesting the necessity of integrating the health education programs on accidental injury with the healthcare management system in children in the country, focusing on the suburban and county levels where economy was relatively undeveloped or with more floating population.

[Study on the status of unintentional injuries in children under age 7 in Guangzhou].

OBJECTIVE: To understand the prevalence and distribution of unintentional injuries in children under age 7 in Guangzhou. METHODS: Data was descriptively analyzed from the Guangzhou Unintentional Injuries Surveillance System among 470 770 children under age 7 living scatter or collectively. RESULTS: The incidence rates of unintentional injuries among children in Guangzhou was 1.48%, among which the incidence rates were: living scatter as 1.11% living collectively as 1.66%, living in urban areas as 1.36% in rural as 2.52%. In order, the proportion of main causes of children's unintentional injuries were as follows: falls (70.54%), animal injuries (8.48%), burn and scald (5.75%), blunt force injuries (3.92%), and road traffic injuries (RTIs) (3.48%). The main body parts being injured were head and face (60.00%), wrist and hand (15.48%), knee and leg (11.70%), elbow and forearm (4.54%), shoulder and arm (2.99%). The degrees of children's unintentional injuries were as follows: mild impairment (85.35%), moderate impairment (9.12%), and severe impairment (0.57%). Places that the patients went were as follows: hospital outpatient department or emergency room (49.66%), inpatient department or ICU (2.06%), home and kindergarten (43.34%). CONCLUSION: The overall incidence rate of children's unintentional injuries under age 7 in Guangzhou was 1.48%, with main causes as fall, animal injuries, burn and scald, blunt force injuries, and RTIs. There were considerable differences of characteristics and distributions on age and areas among the patients.

Tea catechins induce the conversion of preformed lysozyme amyloid fibrils to amorphous aggregates.

Natural polyphenols are major constituents of plant foods and herbs. Numerous studies have demonstrated that natural polyphenols inhibited amyloid formation and destabilized the preformed amyloid fibrils. However, the molecular mechanism for the antiamyloidogenesis of polyphenols is still unclear and remains to be further explored. In the present study, the preformed lysozyme fibrils were used as an in vitro model to study the disruptive effects of tea catechins on amyloid fibrils. Results showed that tea catechins induced the conversion of lysozyme fibrils to amorphous aggregates and inhibited fibril-induced hemolysis. Hydroquinone also showed disruptive effect on the fibrils, whereas phenol and two typical antioxidants, ascorbic acid and alpha-tocopherol, did not affect the fibrillar structure, suggesting that polyphenolic structure is essential for fibril deposition. Correlation analyses indicate that the fibril-depositing effects were related to both the antioxidative potency and hydrophobicity of tea catechins. These findings provide new evidence for comprehensive understanding of the interaction between natural polyphenols and amyloid fibrils.