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Observational studies have linked elevated homocysteine to vascular conditions. Folate intake has been associated with lower homocysteine concentration, although randomised controlled trials of folic acid supplementation to decrease the incidence of vascular conditions have been inconclusive. We investigated determinants of maternal homocysteine during pregnancy, particularly in a folic acid-fortified population.
Data were from the Ottawa and Kingston Birth Cohort of 8085 participants. We used multivariable regression analyses to identify factors associated with maternal homocysteine, adjusted for gestational age at bloodwork. Continuous factors were modelled using restricted cubic splines. A subgroup analysis examined the modifying effect of MTHFR 677C>T genotype on folate, in determining homocysteine concentration.
Participants were recruited in Ottawa and Kingston, Canada, from 2002 to 2009.
Women were recruited when presenting for prenatal care in the early second trimester.
In 7587 participants, factors significantly associated with higher homocysteine concentration were nulliparous, smoking and chronic hypertension, while factors significantly associated with lower homocysteine concentration were non-Caucasian race, history of a placenta-mediated complication and folic acid supplementation. Maternal age and BMI demonstrated U-shaped associations. Folic acid supplementation of >1 mg/d during pregnancy did not substantially increase folate concentration. In the subgroup analysis, MTHFR 677C>T modified the effect of folate status on homocysteine concentration.
We identified determinants of maternal homocysteine relevant to the lowering of homocysteine in the post-folic acid fortification era, characterised by folate-replete populations. A focus on periconceptional folic acid supplementation and improving health status may form an effective approach to lower homocysteine.
Superior and inferior rice grains have different weights and are located on the upper primary branch and lower secondary branches of the panicle, respectively. To study differences in germination vigour of these two types of grain, a number of factors were investigated from 0 to 48 h of germination. The present study demonstrated that in inferior grains the starch granule structure was looser at 0 h, with full water absorption at 48 h, while in superior grains the structure was tight and dense. Relative water content increased, and dry matter decreased, more rapidly in inferior grains than in superior ones. Abscisic acid and gibberellin levels, as well as α-amylase activity, also changed more rapidly in inferior grains, while soluble sugar content and amylase coding gene expression increased more rapidly in inferior than superior grains during early germination. The expression of OsGAMYB was higher in inferior grains at 24 h but higher in superior grains at 48 h. The phenotypic index of seedlings was higher in seedlings from superior grains at the two-leaf stage. However, the thousand-grain weight and yield per plant in superior and inferior plants showed no significant difference at harvest. The present study indicates that inferior grains germinate faster than superior ones in the early germination stage. Although inferior grains produced weaker seedlings, it is worthwhile using them in rice production due to their comparative yield potential over that of superior grains.
Bacillary dysentery continues to be a major health issue in developing countries and ambient temperature is a possible environmental determinant. However, evidence about the risk of bacillary dysentery attributable to ambient temperature under climate change scenarios is scarce. We examined the attributable fraction (AF) of temperature-related bacillary dysentery in urban and rural Hefei, China during 2006–2012 and projected its shifting pattern under climate change scenarios using a distributed lag non-linear model. The risk of bacillary dysentery increased with the temperature rise above a threshold (18·4 °C), and the temperature effects appeared to be acute. The proportion of bacillary dysentery attributable to hot temperatures was 18·74% (95 empirical confidence interval (eCI): 8·36–27·44%). Apparent difference of AF was observed between urban and rural areas, with AF varying from 26·87% (95% eCI 16·21–36·68%) in urban area to −1·90% (95 eCI −25·03 to 16·05%) in rural area. Under the climate change scenarios alone (1–4 °C rise), the AF from extreme hot temperatures (>31·2 °C) would rise greatly accompanied by the relatively stable AF from moderate hot temperatures (18·4–31·2 °C). If climate change proceeds, urban area may be more likely to suffer from rapidly increasing burden of disease from extreme hot temperatures in the absence of effective mitigation and adaptation strategies.
Chitotriosidase, secreted by activated macrophages, is a biomarker of activated macrophages. In this study, we explored whether chitotriosidase could be adopted as a biomarker to evaluate the curative effect on tuberculosis (TB). Five counties were randomly selected out of 122 counties/cities/districts in Hunan Province, China. Our cases were all TB patients who were newly diagnosed or had been receiving treatment at the Centers for Disease Control (CDCs) of these five counties between April and August in 2009. Healthy controls were selected from a community health facility in the Kaifu district of Changsha City after frequency-matching of gender and age with the cases. Chitotriosidase activity was evaluated by a fluorometric assay. Categorical variables were analysed with the χ2 test. Measurement data in multiple groups were tested with analysis of variance and least significant difference (LSD). Correlation between chitotriosidase activity and the degree of radiological extent (DRE) was examined by Spearman's rank correlation test. The average chitotriosidase activity levels of new TB cases, TB cases with different periods of treatment (<3, 3–6, >6 months) and the control group were 54·47, 34·77, 21·54, 12·73 and 10·53 nmol/h.ml, respectively. Chitotriosidase activity in TB patients declined along with the continuity of treatment. The chitotriosidase activity of both smear-positive and the smear-negative pulmonary TB patients decreased after 6 months' treatment to normal levels (P < 0·05). Moreover, chitotriosidase activity was positively correlated with DRE (r = 0·607, P < 0·001). Our results indicate that chitotriosidase might be a marker of TB treatment effects. However, further follow-up study of TB patients is needed in the future.
Co-infections of cystic echinococcosis (CE) and HIV/AIDS is rare. We report four CE cases that were HIV positive. Three out of the four patients underwent a surgical operation to remove the hydatid cysts in their livers. The operation confirmed that in two of the cases their cysts had ruptured. These patients were given 3 months of albendazole after the operation. Follow-up showed they were remarkably improved in term of their health, although they were still HIV antibody positive 6 months after surgical treatment. Interestingly, the treatment remarkably increased their CD4+ cell population. We showed that surgery is suitable for treating hepatic cystic echinococcosis with HIV/AIDS co-infection.
To understand the clinical epidemiology and molecular characteristics of human bocavirus (HBoV) infection in children with diarrhoea in Guangzhou, South China, we collected 1128 faecal specimens from children with diarrhoea from July 2010 to December 2012. HBoV and five other major enteric viruses were examined using real-time polymerase chain reaction. Human rotavirus (HRV) was the most prevalent pathogen, detected in 250 (22·2%) cases, followed by enteric adenovirus (EADV) in 76 (6·7%) cases, human astrovirus (HAstV) in 38 (3·4%) cases, HBoV in 17 (1·5%) cases, sapovirus (SaV) in 14 (1·2%) cases, and norovirus (NoV) in 9 (0·8%) cases. Co-infections were identified in 3·7% of the study population and 23·5% of HBoV-positive specimens. Phylogenetic analysis revealed 14 HBoV strains to be clustered into species HBoV1 with only minor variations among them. Overall, the detection of HBoV appears to partially contribute to the overall detection gap for enteric infections, single HBoV infection rarely results in severe clinical outcomes, and HBoV sequencing data appears to support conserved genomes across strains identified in this study.
Pneumonia is an important cause of mortality and morbidity in infants. However, information of risk factors for pneumonia in children aged <6 months is limited. This study aimed to evaluate the risk factors and their contribution to infantile pneumonia in a large population-based survey. Of 24 200 randomly sampled main caregivers invited, 21 248 (87·8%) participated in this study. A structured questionnaire was used to interview the main caregivers. Information regarding whether hospitalization was required, family environment, and medical history were obtained. The prevalence of pneumonia was 0·62% in our study cohort. Multivariate logistic regression analysis showed that preterm birth, congenital cardiopulmonary disease, antibiotic use during pregnancy, maternal overweight, daily prenatal exposure to environmental tobacco smoke, maternal smoking during pregnancy, and visible mould on walls at home are risk factors associated with infantile pneumonia. Further study is warranted to investigate the causality and mechanisms of these novel factors.
Our previous studies demonstrated prompt elevation of proteinase activity in mammary secretion of drying-off cows and goats. The current study examined the progressive changes in composition of cow mammary secretion following drying-off and, in parallel, characterized the mode of peptide neogenesis using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) and liquid chromatography-electrospray-ionization (LC-ESI) MS/MS. The results show that the percentage of casein of total milk protein at time of drying-off was 76%, which dropped to 41%, 24%, and 16%, respectively, 1, 2, and 3 weeks after drying-off. Levels of β-lactoglobulin and α-lactoalbumin in mammary secretions of drying-off cows decreased prominently while levels of lactoferrin, BSA, and casein derived-proteins increased concomitantly compared with regular milk. A fractionation procedure was applied to remove molecules larger than 10 kDa before MALDI-TOF MS and LC-ESI MS/MS and the results show that the MALDI-TOF MS peptide profile of mammary secretion ranging from m/z 600 to 4000 was apparently modified after drying-off for 1 week, whereas species 1590 m/z and 2460 m/z were most obviously enriched compared with regular milk. LC-ESI MS/MS results were used to map peptide sequence with Mascot search server and under no post translational modification to reduce database size and 202 novel β-casein-derived peptides were successfully identified in mammary secretion after drying-off for 1 week in contrast to regular milk. Accordingly at least 48 additional cleavage positions were assigned on β-casein for mammary secretion. Among the 202 novel peptides, 5 are homologous with confirmed opioid agonists, angiotensin 1-converting enzyme inhibitors, or immuno-modulators. In conclusion, peptides are released in situ from milk proteins within short intervals following drying-off in cows. They might play roles in the transition of mammary glands from lactating to non-lactating. With specified post-translational modifications and focused functional screening, novel peptides are yet to be discovered in dry cow mammary secretion.
In-field critical current Ic variations, detected using a short sample, angular Ic(77K, H=5.2kOe, Angle) measurement on the ends of a 20 m coated conductor tape fabricated by the MOD / RABiTS process, are shown to be variations in the Ic(H) anisotropy that exist on subcentimeter length scales. A Ic(75 K, H, Angle) study was performed on segments cut from the tape where the power law exponent of the field dependence, α, Ic ∼H−α was calculated for Ic(H, Angle) data. Two extrema behaviors, anisotropic and isotropic, were identified. The isotropic material is shown to outperform the anisotropic material for a wide range of fields and angles at T=26 K.
We present the temporal and spatial characterization of X-ray sources (at ~1 keV) driven by a 200 TW, 30 fs, 800 nm laser pulse on SILEX-I laser facility at Research Center of Laser Fusion. For laser copper foil interaction with laser intensity between 6 × 1018 W/cm2 and 3 × 1019 W/cm2, the X-ray images show cone-like jet structures. While the yield of X-rays is strongly dependent on the laser intensity, the plasma expansion length is weakly dependent on the laser intensity, and the open angle of the cone-like jet is not correlated to the laser intensity. The formation of the jet structure is attributed to the plasma transverse confine by the self-induced quasi-static magnetic field. An X-ray pedestal 4 ns preceding the main pulse was observed. The correlation between X-ray pedestal and collimated proton beam generation was found.
The ZnO thin film was successfully deposited on a glass substrate at RT by a RF reactive magnetron sputtering method. Structural, chemical, optical, and hydrophilic/hydrophobic properties are measured by using a surface profilometer, an x-ray diffractometry (XRD), an x-ray photoelectron spectroscopy (XPS), a UV-VIS spectrophotometer, and a contact angle system, respectively. Results show that the deposition rate decreases with increasing O2/(Ar+O2) ratio. Otherwise, the best stoichiometric and quality of ZnO thin film was observed at 0.30 of O2/(Ar+O2) ratio by the smallest FWHM and the strong O-Zn bonds. Regardless of O2/(Ar+O2) ratio effect or thickness effect, high transmittance (> 86%) in the visible region is observed, while the UV-shielding characteristics depend upon both the magnitude of film thickness. The film thickness plays a more prominent role in controlling optical properties, especially in the UV-shielding characteristics, than the O2/(Ar+O2) ratio. However, the hydrophobic characteristics can be obtained when the glass coating with ZnO thin films. In general, with properly coated ZnO thin film, we can obtain a glass substrate which is highly transparent in the visible region, has good UV-shielding characteristics, and possesses highly hydrophobic characteristics (self-clean capability), which is highly suitable for applications in the glass industries.
This paper presents a study on the shape control and emission wavelength extension of InP-based InAsSb nanostructures. InGaAs buffer, combined with low growth temperature and medium V/III ratio, provides an effective approach to fabricate InAsSb QDs. By using InGaAsSb sandwich layer to serve as both strain reducing layer and metamorphic buffer layer, the emission wavelength of InAsSb QDs can be extended well beyond 2um, which is very useful for their application as mid-infrared emitters.
In a compression test for a Zr-based bulk metallic glass, a dominant shear band was preserved before fracture by a cylindrical stopper. A heat-affected zone (HAZ) ∼10 μm thick together with shear band was discovered in the center of the deformed sample by preferential ion milling. By using a low aspect ratio sample for compression, diverse micron-scaled HAZs among multiple shear bands were also revealed. Based on above experimental results and the isothermal source model, it was found that the thickness of shear band and its HAZ increased continuously with the progression of shear deformation.
The level of gelatinases in surrounding body fluids of actively remodelling tissue is indicative of basement membrane and extracellular matrix degradation under various physiological and pathological circumstances. To elucidate the association of gelatinase with mammary tissue remodelling during gradual or acute involution, in the first trial, goats milked twice daily (lactation) and goats receiving decreased milking frequency (involution) served to provide a total of 12 milk samples and 11 mammary secretion samples, respectively. In the second trial, 6 cows served to provide samples of dry secretion in 3 consecutive weeks immediately following milk stasis. Gelatin zymography was applied for gelatinase phenotyping and quantification on milk, plasma and the degranulation medium/lysate of milk somatic cells. Results indicated that the most prevalent gelatinase subtype switched from gelatinase A in milk to gelatinase B in involution secretion. Mammary secretion of goats during involution contained marginally higher protein level, significantly lower casein ratio and greater specific capacity of gelatinase B compared with those of milk during lactation. Specific capacities of gelatinases A and B in plasma of goats were similar during lactation and involution, while gelatinase B capacity in degranulation medium/lysates based on unit number of goat somatic cell was significantly higher during involution than during lactation. Milk stasis of cows induced a significant increase in specific capacity of gelatinase B, but not gelatinase A, of dry secretion up to the third week. Results of both trials agree that regional selective accretion of gelatinase B in milk might have played a role in mammary tissue remodelling during involution induced by either decreasing milking frequency or milk stasis. It is suggested that infiltrated polymorphonuclear neutrophils are one of the potential contributors responsible for the accumulation of gelatinase B during involution.
Traumatic optic neuropathy can be treated by various methods including steroids and surgical decompression. Endoscopic optic nerve decompression has been suggested to be effective in treating this condition. The aim of this study was to assess the outcome of treating traumatic optic neuropathy with steroids and endoscopic surgical decompression.
Two hundred and thirty-seven patients with traumatic optic neuropathy were treated with steroids; 176 also consented to endoscopic optic nerve decompression.
The total vision improvement rate was 55 per cent in the 176 patients treated with both steroids and endoscopic optic nerve decompression, compared with 51 per cent in the 61 patients treated with steroids alone; this difference was not statistically significant (p > 0.05). Treatment with steroids plus endoscopic optic nerve decompression resulted in a significantly greater vision improvement in patients with gradual vision loss, compared with those with immediate blindness (68 vs 42 per cent, respectively). Early surgery (within one week) was an important prognostic factor for vision recovery, compared with more delayed surgical treatment (associated vision improvement rates were 60 and 31 per cent, respectively).
Endoscopic optic nerve decompression is a minimally invasive, safe and efficient treatment for traumatic optic neuropathy. Used in combination with steroids, it provides effective rescue for some patients suffering visual loss. It should be undertaken as soon as possible.
We report on deposition and properties of m-plane GaN/InGaN/AlInN structures on LiAlO2 substrates grown by metal organic vapor phase epitaxy (MOVPE). At first, two different buffer structures, one of them including an m-plane AlInN interlayer, were investigated concerning their suitability for the subsequent coalesced single-phase m-plane GaN growth. A series of quantum well structures with different well thickness based on one of these buffers showed absence of polarization-induced electric fields verified by room temperature photoluminescence (RT PL) measurements at different excitation intensities. Furthermore, polarization-resolved PL measurements revealed a high degree of polarization (DoP) of the emitted light with an intensity ratio of 8:1 between light polarized perpendicular and parallel to the c-axis.
The Xinjiang Uygur Autonomous Region, multi-ethnic province in northwestern China, is one of the most important foci of human cystic echinococcosis (CE) in the world. Two Echinococcus granulosus genotypes (G1 and G6) are known to infect the intermediate hosts in this area but, to date, the source of the human infection remains unclear. The current study aimed to genetically analyse 67 hydatid cysts removed from 47 CE patients for which epidemiological, clinical and serological data were also recorded. Mitochondrial cox 1 gene sequencing suggested that the E. granulosus G1 genotype is the major source of infection (45/47 CE patients). Nevertheless, for the first time in China, 2 patients were found with hydatid cysts of the G6 genotype. In addition, 45 E. granulosus gravid tapeworms, isolated from 13 dogs, were genotyped. The majority of adult worms (42/45) exhibited the G1 genotype, whereas 3 adult tapeworms with the G6 genotype were found in one dog, that also harboured E. granulosus tapeworms of the G1 genotype. This sympatric occurrence of G1 and G6 genotypes of E. granulosus, not only in the same area but also in the same definitive host, raises the interesting question of putative genetic recombination between these E. granulosus genotypes.