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The aim of this study was to explore the impact of polymorphism of PD-1 gene and its interaction with tea drinking on susceptibility to tuberculosis (TB). A total of 503 patients with TB and 494 controls were enrolled in this case–control study. Three single-nucleotide polymorphisms of PD-1 (rs7568402, rs2227982 and rs36084323) were genotyped and unconditional logistic regression analysis was used to identify the association between PD-1 polymorphism and TB, while marginal structural linear odds models were used to estimate the interactions. Genotypes GA (OR 1.434), AA (OR 1.891) and GA + AA (OR 1.493) at rs7568402 were more prevalent in the TB patients than in the controls (P < 0.05). The relative excess risk of interaction (RERI) between rs7568402 of PD-1 genes and tea drinking was −0.3856 (95% confidence interval −0.7920 to −0.0209, P < 0.05), which showed a negative interaction. However, the RERIs between tea drinking and both rs2227982 and rs36084323 of PD-1 genes were not statistically significant. Our data demonstrate that rs7568402 of PD-1 genes was associated with susceptibility to TB, and there was a significant negative interaction between rs7568402 and tea drinking. Therefore, preventive measures through promoting the consumption of tea should be emphasised in the high-risk populations.
The risk of environmental contamination by severe acute respiratory coronavirus virus 2 (SARS-CoV-2) in the intensive care unit (ICU) is unclear. We evaluated the extent of environmental contamination in the ICU and correlated this with patient and disease factors, including the impact of different ventilatory modalities.
In this observational study, surface environmental samples collected from ICU patient rooms and common areas were tested for SARS-CoV-2 by polymerase chain reaction (PCR). Select samples from the common area were tested by cell culture. Clinical data were collected and correlated to the presence of environmental contamination. Results were compared to historical data from a previous study in general wards.
In total, 200 samples from 20 patient rooms and 75 samples from common areas and the staff pantry were tested. The results showed that 14 rooms had at least 1 site contaminated, with an overall contamination rate of 14% (28 of 200 samples). Environmental contamination was not associated with day of illness, ventilatory mode, aerosol-generating procedures, or viral load. The frequency of environmental contamination was lower in the ICU than in general ward rooms. Eight samples from the common area were positive, though all were negative on cell culture.
Environmental contamination in the ICU was lower than in the general wards. The use of mechanical ventilation or high-flow nasal oxygen was not associated with greater surface contamination, supporting their use and safety from an infection control perspective. Transmission risk via environmental surfaces in the ICUs is likely to be low. Nonetheless, infection control practices should be strictly reinforced, and transmission risk via droplet or airborne spread remains.
Ontology alignment is an important and inescapable problem for the interconnections of two ontologies stating the same concepts. Ontology alignment evaluation initiative (OAEI) has been taken place for more than a decade to monitor and help the progress of the field and to compare systematically existing alignment systems. As of 2018, the evaluation of systems is partly transitioned to the HOBBIT platform. This paper contains the description of our alignment system, simulated annealing-based ontology matching (SANOM), and its adaption into the HOBBIT platform. The outcomes of SANOM on the HOBBIT for several OAEI tracks are reported, and the results are compared with other competing systems in the corresponding tracks.
We report an epitaxy growth and characterization of InAs photodetector (PD) on virtual Ge/Si and GaP/Si substrates. The effect of different types of the virtual substrate on the structure and performance of the InAs PD was studied. Although the lattice mismatch between InAs and Si is large (11.6%), close to 100% relaxation of InAs was achieved on both virtual substrates. A higher surface roughness was observed in the InAs layer grown GaP/Si as compared with that of Ge/Si. InAs PD with room temperature blackbody specific detectivity of ~5 × 108 cm·Hz1/2/W is achieved in photovoltaic mode on both types of virtual substrate.
The globally threatened Straw-headed Bulbul Pycnonotus zeylanicus is one of South-East Asia’s most imperilled songbirds due to the surging demand for the species in the regional bird trade. Recently uplisted from Vulnerable to Endangered, populations of the Straw-headed Bulbul have been extirpated from Java, Thailand and possibly Sumatra while those in Borneo and Peninsular Malaysia are in decline. Intriguingly, a significant yet rarely documented population of this species persists in Singapore. A major stronghold in Singapore is Ubin Island where a population is known since the 1920s. Using a long-term citizen science dataset rarely available for South-East Asian bird species, we determined the status and population trends of the Straw-headed Bulbul in Singapore over a 10–15 year period using Poisson regression models and standardised population indices. We found that the Straw-headed Bulbul population has increased at a rate of 3.69 ± 1.21% per annum on Ubin Island, while the population on Singapore Island remained stable (0.56% per annum) from 2000 to 2016. The population trends in Singapore contrast starkly with the declines reported elsewhere in South-East Asia. We estimated the population in Singapore to be a minimum of 202 individuals, distributed over multiple forest patches. The largest subpopulation of about 110 adult individuals persists on Ubin and which alone forms between 6.5–18.3% of the estimated global population in 2016. Given this unique situation, we recommend a number of conservation measures for the Straw-headed Bulbul to better protect the species, including: (1) an expansion of the protected area network in Singapore to include Ubin as a reserve, (2) the development of an endangered species management plan and, (3) the establishment of ex-situ conservation programmes in zoological institutions and wildlife centres in the region.
Autophagy process in Toxoplasma gondii plays a vital role in regulating parasite survival or death. Thus, once having an understanding of certain effects of autophagy on the transformation of tachyzoite to bradyzoite this will allow us to elucidate the function of autophagy during parasite development. Herein, we used three TgAtg proteins involved in Atg8 conjugation system, TgAtg3, TgAtg7 and TgAtg8 to evaluate the autophagy level in tachyzoite and bradyzoite of Toxoplasma in vitro based on Pru TgAtg7-HA transgenic strains. We showed that both TgAtg3 and TgAtg8 were expressed at a significantly lower level in bradyzoites than in tachyzoites. Importantly, the number of parasites containing fluorescence-labelled TgAtg8 puncta was significantly reduced in bradyzoites than in tachyzoites, suggesting that autophagy is downregulated in Toxoplasma bradyzoite in vitro. Moreover, after treatment with drugs, bradyzoite-specific gene BAG1 levels decreased significantly in rapamycin-treated bradyzoites and increased significantly in 3-MA-treated bradyzoites in comparison with control bradyzoites, indicating that Toxoplasma autophagy is involved in the transformation of tachyzoite to bradyzoite in vitro. Together, it is suggested that autophagy may serve as a potential strategy to regulate the transformation.
The widespread decline of migratory shorebirds in the East Asian-Australasian Flyway (EAAF) is one of the greatest crises for migrating birds. Among the migratory species with known population trends, 88% (22 of 25 species) show population declines, and seven have been listed as threatened or Near Threatened in the IUCN Red List. The decline of migratory shorebirds is related to the deterioration of stopping sites (including staging and stopping sites) in the Yellow Sea, including loss of intertidal wetlands, spread of invasive smooth cordgrass Spartina alterniflora on intertidal flats, an increase in pollution, and an increase in human disturbance. We review research concerning shorebird migration through the Yellow Sea and highlight key research activities required for the conservation of shorebirds in the region. These activities include: confirming the population consequences of loss of stopping sites, estimating migration timing and numbers of shorebirds at stopping sites, determining the differing abilities of species to use alternative habitats, understanding intra- and interspecific differences in the use of stopping sites, maintaining and expanding surveys on shorebirds and habitat condition, and identifying threats to shorebirds beyond habitat loss by reclamation. The information generated by these research activities is required for the design and selection of effective conservation actions to reverse the decline in shorebird populations.
To explore (i) the prevalence of thyroid dysfunction in populations with adequate and excessive iodine intakes and (ii) the effect of iodine exposure on the prevalence of thyroid dysfunction.
Cross-sectional study was conducted in Hebei in 2010. The population was classified as having adequate or excessive iodine intake according to the iodine concentration in drinking water. Demographic information was collected by questionnaire. Levels of serum thyroid hormones, thyroid autoantibodies and iodine in drinking water and urine were measured.
Villages with adequate or excessive drinking water iodine in Hebei Province, People’s Republic of China.
A total of 854 men and women aged 20–50 years who had lived in the surveyed areas for over 5 years, including 348 from the adequate iodine area (AIA) and 506 from the excessive iodine area (EIA).
Median urinary iodine concentration was 185 μg/l in AIA and 1152 μg/l in EIA. The prevalence of thyroid dysfunction in AIA was 10·3 %, which included 1·1 % with hypothyroidism and 8·1 % with subclinical hypothyroidism; and 20·6 % in EIA, which included 3·6 % with hypothyroidism and 13·6 % with subclinical hypothyroidism. The positive rates of thyroglobulin antibody were 16·1 % in AIA and 11·9 % in EIA; the positive rates of thyroperoxidase antibody were 20·7 % in AIA and 16·4 % in EIA.
Excessive iodine intake may lead to increased prevalence of biochemical thyroid dysfunction, especially biochemical hypothyroidism. This is not related to an increase in prevalence of thyroid antibodies. Women are more susceptible to iodine excess.
Dietary fibre intake has been suggested to reduce blood glucose levels in diabetic patients, particularly when glycosylated Hb (HbA1c) levels are high. In the present study, we used a quantile regression (QR) approach to characterise the possible heterogeneous associations of dietary fibre intake with HbA1c levels in Chinese diabetic patients. A total of 497 diabetic patients participated in the baseline survey in 2006 and in the follow-up survey in 2011, both of which were conducted in Pudong New Area of Shanghai, China. Structured in-person interviews were conducted to collect information on demographic characteristics and lifestyle factors. Dietary intake was assessed using a validated FFQ. Blood samples were collected during the interviews for biochemical assays. QR models were used to examine the heterogeneous associations of dietary factors with HbA1c levels. A significant marginal association of insoluble dietary fibre intake with subsequent HbA1c levels was observed only when the HbA1c level was over 6·8 %. The associations appeared to be greater when the quantile levels of HbA1c were higher. The coefficient estimates were − 0·174 (95 % CI − 0·433, − 0·025) at the quantile of 0·60, − 0·200 (95 % CI − 0·306, − 0·008) at 0·70, − 0·221 (95 % CI − 0·426, − 0·117) at 0·80, and − 0·389 (95 % CI − 0·516, − 0·018) at 0·90. A similar pattern was observed for the associations of dietary glycaemic index (GI) value with HbA1c levels. In conclusion, the present results indicate that the associations of insoluble dietary fibre intake and GI value with subsequent HbA1c levels depend on glycaemic control status in Chinese diabetic patients. More studies are required to confirm our findings.
Nature and mechanism of interfacial reactions between boron nitride nanotubes (BNNTs) and aluminum matrix at high temperature (650 °C) are studied using high-resolution transmission electron microscopy (HRTEM). This study analyzes the feasibility of the use of BNNTs as reinforcement in aluminum matrix composites for structural application, for which interface plays a critical role. Thermodynamic comparison of aluminum (Al)-BNNT with analogous Al-carbon nanotube (Al-CNT) system reveals lesser amount of reaction in the former. Experimental observation also reveals thin (∼7 nm) reaction-product formation at Al-BNNT interface even after 120 min of exposure at 650 °C. The spatial distribution of the reaction-product species at the interface is governed by the competitive diffusion of N, Al, and B. Morphology of the reaction products are influenced by their orientation relationship with BNNT walls. A theoretical prediction on Al-BNNT interface in macroscale composite suggests the formation of strong bond between the matrix and reinforcement phase.
Recent studies indicate that bipolar disorder is associated with mitochondrial dysfunction and oxidative stress. Previous studies in our laboratory have shown that the mood stabilizer lithium inhibits oxidative stress. The α,β-unsaturated aldehyde 4-hydroxy-2-nonenal (4-HNE), a major product of lipid peroxidation, is able to exert cytotoxicity and disturb cellular function by forming protein adducts. The purpose of this study is to determine whether chronic lithium treatment prevents 4-HNE-protein adduction in an amphetamine-induced hyperactive mania-like model. We found that repeated amphetamine stimulation significantly induced hyperactive behaviour, decreased activities of mitochondrial complexes I and III, and increased 4-HNE-protein adducts in rat frontal cortex, and that chronic lithium treatment inhibited both amphetamine-induced hyperactivity and 4-HNE-protein adduction. Monoamine neurotransmitters are involved in the aetiology and pathology of bipolar disorder and other psychiatric diseases, and also contribute significantly to amphetamine-induced behavioural effects. Vesicular monoamine transporter 2 (VMAT2) is critical in packaging monoamine neurotransmitters. We found that 4-HNE can form protein adducts with VMAT2. Repeated amphetamine stimulation significantly increased 4-HNE-VMAT2 adducts, while chronic lithium treatment reduced amphetamine-increased 4-HNE-VMAT2 adducts in rat frontal cortex. Our findings suggest that chronic lithium treatment may inhibit amphetamine-induced hyperactive mania-like behaviour by preventing 4-HNE-VMAT2 adduction. This finding also indicates that prevention of 4-HNE-VMAT2 adduction may contribute in part to the pharmacological action of lithium for the treatment of bipolar disorder.
Fusion of nucleoli or nucleolus precursor bodies (NPBs) has been observed during somatic cell interphase and pronuclear development of human zygotes; however, the underlying mechanism is unknown. NPB fusion and its regulation by mitogen-activated protein kinase (MAPK) and maturation-promoting factor (MPF) were studied in activated mouse oocytes. Small NPBs appeared about 4 h after ethanol activation, and took about 1.5 h to fuse into a large NPB, which persisted for about 10 h before disappearance. Analysis of the temporal windows for kinase action indicated that a high MAPK activity during the first 2 h and a low MPF activity during the first 3–4 h after activation were essential for subsequent NPB fusion. A preactivation decline in MAPK activity was associated with decreased NPB fusion following activation of aged oocytes. While MAPK inactivation by regulator U0126 prevented NPB fusion in oocytes activated by ethanol or 5 min Sr2+ treatments, it had no effect on oocytes fertilized or activated by 6 h Sr2+ treatment. In most cases, while rates of pronuclear formation did not differ, rates of NPB fusion differed significantly between different treatments. Our results suggest that: (i) the MAPK and MPF activities at the initial stage of activation regulate NPB fusion after pronuclear formation; (ii) pronuclear assembly and NPB fusion are two separable events that might be controlled by different mechanisms; and (iii) high MAPK activity and low MPF activity at the initial stage of activation is essential for NPB fusion when only one calcium rise is induced by ethanol, while inhibition of MAPK activity does not affect NPB fusion when the repetitive intracellular Ca2+ rises are induced after fertilization.
It is known that levels of brain natriuretic peptide predict outcomes of treatment for adults with decompensated heart failure. We hypothesized that it could predict outcomes in children with this condition.
We divided retrospectively 82 patients with serial measurements of brain natriuretic peptide into 3 groups: those who survived and did not need readmission within less than 60 days; those who survived but needed readmission within less than 60 days; and those who died in hospital or within less than 60 days. Initial and final levels of the peptide correlated with adverse outcomes.
The percent change in level of the peptide was minus 78 percent, minus 38 percent, and 138 percent in the readmission-free group, the readmitted, and nonsurviving groups, respectively. Final levels were significantly lower in the readmission-free group than in the readmitted and nonsurviving groups (p equals 0.013 and p is less than 0.00001, respectively) and in the readmitted group than in the nonsurvivors (p equals 0.013). On univariate analysis, the final level, the change in level, and the percentage change in level significantly predicted outcomes (p equals 0.0002, 0.0072 and 0.0005, respectively). On multivariate analysis, only the final level of the peptide significantly predicted outcomes (p equals 0.01).
A final level of brain natriuretic peptide of greater than or equal to 760 picograms per millilitre strongly predicted an adverse outcome. Patients with higher final levels may be at higher risk of death and readmission, suggesting that this variable effectively predicts the response to treatment and prognosis in children with heart failure.
Neonates with congenital cardiac disease are a special population. They are often critically ill, and need prolonged intravenous access. To date, no study has evaluated the efficacy and safety of peripherally inserted central venous catheters placed in this unique population. Our goal was to evaluate the use of such catheters in neonates with critical congenital cardiac disease, and to study features such as duration of use, reasons for removal of catheters, and complications. We inserted a total of 124 catheters in 115 neonates with critical congenital cardiac disease who were admitted to the Intensive Care Unit at Texas Children's Hospital from August 2002 to August 2004. The patients had a mean age of 10 days, and a mean weight of 3.1 kilograms. The peripherally inserted catheters were in place for a mean of 22.3 days. Therapy was completed in 76.6% patients at the time of removal of the catheter. The incidence of occlusion, dislodgement, and thrombus was 4.0%, 2.4%, and 1.6%, respectively. The infection rate was 3.6 per 1000 catheter-days, with a median onset on 37 days after placement. We conclude that central venous catheters, when inserted peripherally, provide reliable and safe access for prolonged intravenous therapy in neonates with critical congenital cardiac disease.
The flow fields behind the Mach stem in steady-state Mach reflections are analysed theoretically and numerically. When the angle between the slipline and the reflecting plane is sufficiently small, the subsonic flow just behind the Mach stem can be described by the isentropic small-disturbance equation. Using this analytical model, a very simple algebraic expression for the shape of the Mach stem is obtained. It is found that the Mach stem is well-approximated by a circular arc with very small curvature. The prediction by the model agrees very well with numerical computations.
Haplotype inference has become an important part of human genetic data analysis due to its functional and statistical advantages over the single-locus approach in linkage disequilibrium mapping. Different statistical methods have been proposed for detecting haplotype – disease associations using unphased multi-locus genotype data, ranging from the early approach by the simple gene-counting method to the recent work using the generalized linear model. However, these methods are either confined to case – control design or unable to yield unbiased point and interval estimates of haplotype effects. Based on the popular logistic regression model, we present a new approach for haplotype association analysis of human disease traits. Using haplotype-based parameterization, our model infers the effects of specific haplotypes (point estimation) and constructs confidence interval for the risks of haplotypes (interval estimation). Based on the estimated parameters, the model calculates haplotype frequency conditional on the trait value for both discrete and continuous traits. Moreover, our model provides an overall significance level for the association between the disease trait and a group or all of the haplotypes. Featured by the direct maximization in haplotype estimation, our method also facilitates a computer simulation approach for correcting the significance level of individual haplotype to adjust for multiple testing. We show, by applying the model to an empirical data set, that our method based on the well-known logistic regression model is a useful tool for haplotype association analysis of human disease traits.
We investigated the spatial distribution of fruiting in Dryobalanops aromatica (Dipterocarpaceae), a mast-seeding emergent tree that is found in the tropical rain forests of Borneo. Of 393 adults (diameter at breast height (dbh) > 30 cm) in a 52-ha area, 143 (36.4%) individuals fruited. A second-order spatial analysis, based on Ripley's K-function, revealed that fruiting trees were significantly (P < 0.05) aggregated with respect to the total population over distances of 15–115 m. Thus, the spatial distribution of fruiting trees was more aggregated than expected from the adult tree distribution, which itself was aggregated within the study plot. Logistic regression analysis showed that fruiting trees had a significantly greater dbh and were surrounded by more conspecific adults per ha than non-fruiting individuals. Moreover, fruiting trees were found at higher elevations, on steeper slopes, and on sandy rather than clayey soils. In contrast, annual diameter growth, adult density over areas < 1 ha, and slope convexity did not significantly affect fruiting probability. The ratio of seedling (20 cm ≤ h < 60 cm) and sapling (60 cm ≤ h < 300 cm) density to adult density was higher in sites at higher elevations, on steeper slopes, and on sandy soils than that for lower elevations, flat slopes and clayey soils. This suggests that the aggregation of fruiting trees occurred not only at the time of the study, but that it had occurred repeatedly in the past, at the high-elevation, steep-sloped, sandy sites. Thus, site conditions probably affect the dynamics and spatial structure of local populations through differences in fruiting frequency among trees experiencing different site conditions.
In the present work, a novel method is proposed to re-construct voids in passivated metal interconnections. In this method, the conventional SEM and EBIC systems are assembled and utilized without much modification. In principle, a constant current is applied to the metal interconnections while an electron beam is scanning and impinging upon the surface of the sample. The voltage at the terminals is monitored simultaneously during electron beam scanning. Resistance change, and hence voltage perturbation are expected when the electron beam approaches the defective area, caused by uneven electron beam heating (EBH) and heat transmission. Information on defects or voids is thus obtained by analyzing the voltage alteration. Finite element simulation showed that the recorded voltage perturbation is not dependent of the length of the interconnect, but a linear function of the void volume. Thus, the method is essentially useful as the metal length has increased tremendously in copper technology. In addition, it can provide the void size and depth, with the possibility to reconstruct the entire void shape in 3D.