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1.
Nature ; 605(7910): 483-489, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35585346

RESUMEN

New particle formation in the upper free troposphere is a major global source of cloud condensation nuclei (CCN)1-4. However, the precursor vapours that drive the process are not well understood. With experiments performed under upper tropospheric conditions in the CERN CLOUD chamber, we show that nitric acid, sulfuric acid and ammonia form particles synergistically, at rates that are orders of magnitude faster than those from any two of the three components. The importance of this mechanism depends on the availability of ammonia, which was previously thought to be efficiently scavenged by cloud droplets during convection. However, surprisingly high concentrations of ammonia and ammonium nitrate have recently been observed in the upper troposphere over the Asian monsoon region5,6. Once particles have formed, co-condensation of ammonia and abundant nitric acid alone is sufficient to drive rapid growth to CCN sizes with only trace sulfate. Moreover, our measurements show that these CCN are also highly efficient ice nucleating particles-comparable to desert dust. Our model simulations confirm that ammonia is efficiently convected aloft during the Asian monsoon, driving rapid, multi-acid HNO3-H2SO4-NH3 nucleation in the upper troposphere and producing ice nucleating particles that spread across the mid-latitude Northern Hemisphere.

2.
Proc Natl Acad Sci U S A ; 119(44): e2214227119, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36279464

RESUMEN

LUBAC-mediated linear ubiquitination plays a pivotal role in regulation of cell death and inflammatory pathways. Genetic deficiency in LUBAC components leads to severe immune dysfunction or embryonic lethality. LUBAC has been extensively studied for its role in mediating TNF signaling. However, Tnfr1 knockout is not able to fully rescue the embryonic lethality of LUBAC deficiency, suggesting that LUBAC may modify additional key cellular substrates in promoting cell survival. GPx4 is an important selenoprotein involved in regulating cellular redox homeostasis in defense against lipid peroxidation-mediated cell death known as ferroptosis. Here we demonstrate that LUBAC deficiency sensitizes to ferroptosis by promoting GPx4 degradation and downstream lipid peroxidation. LUBAC binds and stabilizes GPx4 by modulating its linear ubiquitination both in normal condition and under oxidative stress. Our findings identify GPx4 as a key substrate of LUBAC and a previously unrecognized role of LUBAC-mediated linear ubiquitination in regulating cellular redox status and cell death.


Asunto(s)
Receptores Tipo I de Factores de Necrosis Tumoral , Ubiquitina , Receptores Tipo I de Factores de Necrosis Tumoral/genética , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , FN-kappa B/metabolismo , Ubiquitinación
3.
Environ Sci Technol ; 58(3): 1601-1614, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38185880

RESUMEN

Highly oxygenated organic molecules (HOMs) are a major source of new particles that affect the Earth's climate. HOM production from the oxidation of volatile organic compounds (VOCs) occurs during both the day and night and can lead to new particle formation (NPF). However, NPF involving organic vapors has been reported much more often during the daytime than during nighttime. Here, we show that the nitrate radicals (NO3), which arise predominantly at night, inhibit NPF during the oxidation of monoterpenes based on three lines of observational evidence: NPF experiments in the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber at CERN (European Organization for Nuclear Research), radical chemistry experiments using an oxidation flow reactor, and field observations in a wetland that occasionally exhibits nocturnal NPF. Nitrooxy-peroxy radicals formed from NO3 chemistry suppress the production of ultralow-volatility organic compounds (ULVOCs) responsible for biogenic NPF, which are covalently bound peroxy radical (RO2) dimer association products. The ULVOC yield of α-pinene in the presence of NO3 is one-fifth of that resulting from ozone chemistry alone. Even trace amounts of NO3 radicals, at sub-parts per trillion level, suppress the NPF rate by a factor of 4. Ambient observations further confirm that when NO3 chemistry is involved, monoterpene NPF is completely turned off. Our results explain the frequent absence of nocturnal biogenic NPF in monoterpene (α-pinene)-rich environments.


Asunto(s)
Contaminantes Atmosféricos , Monoterpenos Bicíclicos , Ozono , Compuestos Orgánicos Volátiles , Monoterpenos/química , Nitratos/química , Aerosoles/análisis , Compuestos Orgánicos Volátiles/química
4.
BMC Psychiatry ; 24(1): 261, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38594691

RESUMEN

BACKGROUND: Major depressive disease (MDD), schizophrenia (SCZ), and bipolar disorder (BD) are common psychiatric disorders, and their relationship with thyroid cancer has been of great interest. This study aimed to investigate the potential causal effects of MDD, SCZ, BD, and thyroid cancer. METHODS: We used publicly available summary statistics from large-scale genome-wide association studies to select genetic variant loci associated with MDD, SCZ, BD, and thyroid cancer as instrumental variables (IVs), which were quality controlled and clustered. Additionally, we used three Mendelian randomization (MR) methods, inverse variance weighted (IVW), MR-Egger regression and weighted median estimator (WME) methods, to estimate the bidirectional causal relationship between psychiatric disorders and thyroid cancer. In addition, we performed heterogeneity and multivariate tests to verify the validity of the IVs. RESULTS: We used two-sample bidirectional MR analysis to determine whether there was a positive causal association between MDD and thyroid cancer risk. The results of the IVW analysis (OR = 3.956 95% CI = 1.177-13.299; P = 0.026) and the WME method (OR = 5.563 95% CI = 0.998-31.008; P = 0.050) confirmed that MDD may increase the risk of thyroid cancer. Additionally, our study revealed a correlation between genetic susceptibility to SCZ and thyroid cancer (OR = 1.532 95% CI = 1.123-2.088; P = 0.007). The results of the WME method analysis based on the median estimate (OR = 1.599 95% CI = 1.014-2.521; P = 0.043) also suggested that SCZ may increase the risk of thyroid cancer. Furthermore, our study did not find a causal relationship between BD and thyroid cancer incidence. In addition, the results of reverse MR analysis showed no significant causal relationships between thyroid cancer and MDD, SCZ, or BD (P > 0.05), ruling out the possibility of reverse causality. CONCLUSIONS: This MR method analysis provides new evidence that MDD and SCZ may be positively associated with thyroid cancer risk while also revealing a correlation between BD and thyroid cancer. These results may have important implications for public health policy and clinical practice. Future studies will help elucidate the biological mechanisms of these associations and potential confounders.


Asunto(s)
Trastorno Bipolar , Trastorno Depresivo Mayor , Esquizofrenia , Neoplasias de la Tiroides , Humanos , Trastorno Depresivo Mayor/complicaciones , Trastorno Depresivo Mayor/genética , Trastorno Bipolar/complicaciones , Trastorno Bipolar/genética , Esquizofrenia/genética , Depresión , Estudio de Asociación del Genoma Completo , Neoplasias de la Tiroides/epidemiología , Neoplasias de la Tiroides/genética
5.
BMC Pregnancy Childbirth ; 24(1): 410, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38849748

RESUMEN

BACKGROUND: Decision-to-delivery time (DDT), a crucial factor during the emergency caesarean section, may potentially impact neonatal outcomes. This study aims to assess the association between DDT and various neonatal outcomes. METHODS: A comprehensive search of PubMed, Scopus, Cochrane Library, and Google Scholar databases was conducted. A total of 32 eligible studies that reported on various neonatal outcomes, such as Apgar score, acidosis, neonatal intensive unit (NICU) admissions and mortality were included in the review. Studies were selected based on predefined eligibility criteria, and a random-effects inverse-variance model with DerSimonian-Laird estimate of tau² was used for meta-analysis. Heterogeneity and publication bias were assessed using I² statistics and Egger's test, respectively. RESULTS: The meta-analysis revealed a significant association between DDT < 30 min and increased risk of Apgar score < 7 (OR 1.803, 95% CI: 1.284-2.533) and umbilical cord pH < 7.1 (OR 4.322, 95% CI: 2.302-8.115), with substantial heterogeneity. No significant association was found between DDT and NICU admission (OR 0.982, 95% CI: 0.767-1.258) or neonatal mortality (OR 0.983, 95% CI: 0.565-1.708), with negligible heterogeneity. Publication bias was not detected for any outcomes. CONCLUSIONS: This study underscores the association between shorter DDT and increased odds of adverse neonatal outcomes such as low Apgar scores and acidosis, while no significant association was found in terms of NICU admissions or neonatal mortality. Our findings highlight the complexity of DDT's impact, suggesting the need for nuanced clinical decision-making in cases of emergency caesarean sections.


Asunto(s)
Puntaje de Apgar , Cesárea , Humanos , Recién Nacido , Embarazo , Femenino , Cesárea/estadística & datos numéricos , Factores de Tiempo , Unidades de Cuidado Intensivo Neonatal/estadística & datos numéricos , Acidosis/epidemiología , Parto Obstétrico/estadística & datos numéricos , Parto Obstétrico/métodos , Mortalidad Infantil , Resultado del Embarazo/epidemiología
6.
Proc Natl Acad Sci U S A ; 118(4)2021 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-33479177

RESUMEN

Reactive iodine plays a key role in determining the oxidation capacity, or cleansing capacity, of the atmosphere in addition to being implicated in the formation of new particles in the marine boundary layer. The postulation that heterogeneous cycling of reactive iodine on aerosols may significantly influence the lifetime of ozone in the troposphere not only remains poorly understood but also heretofore has never been observed or quantified in the field. Here, we report direct ambient observations of hypoiodous acid (HOI) and heterogeneous recycling of interhalogen product species (i.e., iodine monochloride [ICl] and iodine monobromide [IBr]) in a midlatitude coastal environment. Significant levels of ICl and IBr with mean daily maxima of 4.3 and 3.0 parts per trillion by volume (1-min average), respectively, have been observed throughout the campaign. We show that the heterogeneous reaction of HOI on marine aerosol and subsequent production of iodine interhalogens are much faster than previously thought. These results indicate that the fast formation of iodine interhalogens, together with their rapid photolysis, results in more efficient recycling of atomic iodine than currently considered in models. Photolysis of the observed ICl and IBr leads to a 32% increase in the daytime average of atomic iodine production rate, thereby enhancing the average daytime iodine-catalyzed ozone loss rate by 10 to 20%. Our findings provide direct field evidence that the autocatalytic mechanism of iodine release from marine aerosol is important in the atmosphere and can have significant impacts on atmospheric oxidation capacity.

7.
Eur Arch Otorhinolaryngol ; 281(3): 1603-1608, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38150022

RESUMEN

OBJECTIVE: Report three cases of simultaneous triple semicircular canal occlusion (TSCO) and cochlear implantation (CI) as the treatment of intractable Meniere's disease (MD). CASE REPORTS: Patients with MD can present occasionally with intractable vertigo and profound sensorineural hearing loss (SNHL). TSCO and CI have been proposed to control vertigo and restore profound deafness in patients with MD separately. However, a few studies have reported simultaneous TSCO and CI in the same surgical procedure for the treatment of MD. In the present study, we described three patients with MD showing incapacitating vertigo and severe SNHL who underwent simultaneous TSCO and CI after examinations of auditory system, vestibular system, and imaging. Their symptoms were significantly alleviated during the follow-up period. CONCLUSION: The combined TSCO and CI remains a viable treatment option which is effective for the control of vertigo as well as the restoring of hearing in patients with MD.


Asunto(s)
Implantación Coclear , Pérdida Auditiva Sensorineural , Enfermedad de Meniere , Humanos , Enfermedad de Meniere/complicaciones , Enfermedad de Meniere/cirugía , Vértigo/etiología , Vértigo/cirugía , Canales Semicirculares/cirugía , Audición , Pérdida Auditiva Sensorineural/etiología , Pérdida Auditiva Sensorineural/cirugía
8.
Environ Sci Technol ; 57(6): 2297-2309, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36716278

RESUMEN

The mechanistic pathway by which high relative humidity (RH) affects gas-particle partitioning remains poorly understood, although many studies report increased secondary organic aerosol (SOA) yields at high RH. Here, we use real-time, molecular measurements of both the gas and particle phase to provide a mechanistic understanding of the effect of RH on the partitioning of biogenic oxidized organic molecules (from α-pinene and isoprene) at low temperatures (243 and 263 K) at the CLOUD chamber at CERN. We observe increases in SOA mass of 45 and 85% with increasing RH from 10-20 to 60-80% at 243 and 263 K, respectively, and attribute it to the increased partitioning of semi-volatile compounds. At 263 K, we measure an increase of a factor 2-4 in the concentration of C10H16O2-3, while the particle-phase concentrations of low-volatility species, such as C10H16O6-8, remain almost constant. This results in a substantial shift in the chemical composition and volatility distribution toward less oxygenated and more volatile species at higher RH (e.g., at 263 K, O/C ratio = 0.55 and 0.40, at RH = 10 and 80%, respectively). By modeling particle growth using an aerosol growth model, which accounts for kinetic limitations, we can explain the enhancement in the semi-volatile fraction through the complementary effect of decreased compound activity and increased bulk-phase diffusivity. Our results highlight the importance of particle water content as a diluting agent and a plasticizer for organic aerosol growth.


Asunto(s)
Contaminantes Atmosféricos , Monoterpenos , Monoterpenos/química , Humedad , Aerosoles
9.
Environ Sci Technol ; 56(19): 14166-14177, 2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-36126141

RESUMEN

Nucleation of neutral iodine particles has recently been found to involve both iodic acid (HIO3) and iodous acid (HIO2). However, the precise role of HIO2 in iodine oxoacid nucleation remains unclear. Herein, we probe such a role by investigating the cluster formation mechanisms and kinetics of (HIO3)m(HIO2)n (m = 0-4, n = 0-4) clusters with quantum chemical calculations and atmospheric cluster dynamics modeling. When compared with HIO3, we find that HIO2 binds more strongly with HIO3 and also more strongly with HIO2. After accounting for ambient vapor concentrations, the fastest nucleation rate is predicted for mixed HIO3-HIO2 clusters rather than for pure HIO3 or HIO2 ones. Our calculations reveal that the strong binding results from HIO2 exhibiting a base behavior (accepting a proton from HIO3) and forming stronger halogen bonds. Moreover, the binding energies of (HIO3)m(HIO2)n clusters show a far more tolerant choice of growth paths when compared with the strict stoichiometry required for sulfuric acid-base nucleation. Our predicted cluster formation rates and dimer concentrations are acceptably consistent with those measured by the Cosmic Leaving Outdoor Droplets (CLOUD) experiment. This study suggests that HIO2 could facilitate the nucleation of other acids beyond HIO3 in regions where base vapors such as ammonia or amines are scarce.

10.
Environ Sci Technol ; 56(19): 13931-13944, 2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-36137236

RESUMEN

Dimethyl sulfide (DMS) influences climate via cloud condensation nuclei (CCN) formation resulting from its oxidation products (mainly methanesulfonic acid, MSA, and sulfuric acid, H2SO4). Despite their importance, accurate prediction of MSA and H2SO4 from DMS oxidation remains challenging. With comprehensive experiments carried out in the Cosmics Leaving Outdoor Droplets (CLOUD) chamber at CERN, we show that decreasing the temperature from +25 to -10 °C enhances the gas-phase MSA production by an order of magnitude from OH-initiated DMS oxidation, while H2SO4 production is modestly affected. This leads to a gas-phase H2SO4-to-MSA ratio (H2SO4/MSA) smaller than one at low temperatures, consistent with field observations in polar regions. With an updated DMS oxidation mechanism, we find that methanesulfinic acid, CH3S(O)OH, MSIA, forms large amounts of MSA. Overall, our results reveal that MSA yields are a factor of 2-10 higher than those predicted by the widely used Master Chemical Mechanism (MCMv3.3.1), and the NOx effect is less significant than that of temperature. Our updated mechanism explains the high MSA production rates observed in field observations, especially at low temperatures, thus, substantiating the greater importance of MSA in the natural sulfur cycle and natural CCN formation. Our mechanism will improve the interpretation of present-day and historical gas-phase H2SO4/MSA measurements.

11.
Eur J Pediatr ; 181(9): 3401-3411, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35802207

RESUMEN

The associations of early-life head circumference (HC) with child neurodevelopmental and mental health among generally healthy population remain unclear. We aimed to examine the associations of early-life HC trajectories with cognitive development and emotional and behavioral problems in adolescence and to identify the HC growth-sensitive period. We conducted a prospective, community-based birth cohort study in rural western China, and 745 adolescents aged 10-14 years were followed between June and December 2016. We assessed their HC eight times during the first 2 years of life and their adolescent cognitive, emotional, and behavioral outcomes using the Wechsler Intelligence Scale for Children-IV and Youth Self-Report-2001, respectively. We applied group-based trajectory modeling to identify the HC trajectories and conditional growth to derive the HC growth-sensitive periods. We identified five distinct HC trajectories characterized as Start below average-then decrease (7.8% of the sample), Start below average-then increase (6.8%), Start average-then decrease (33%), Consistently average (38%), and Consistently above average (14%). Infants in the trajectory of consistently above average had higher cognitive scores in adolescence compared to those from suboptimal trajectories, with adjusted mean differences ranging from 2.84 to 8.99 points. The conditional gains showed that the HC growth-sensitive period was between 0 and 18 months for child cognition. We found null associations between HC measures and adolescent emotional and behavioral problem scores. CONCLUSION: Early-life HC trajectories were associated with adolescent cognitive development. HC may serve as an inexpensive screening tool to monitor child development at risk during the first 18 months, particularly in resource-limited settings. WHAT IS KNOWN: • Postnatal head circumference (HC) has been shown to be associated with cognitive development in infants who were born premature and/or fetal growth restriction, while inconsistent associations were reported among generally healthy populations, especially in low- and middle- income countries, challenging its utility in public health practices. WHAT IS NEW: • Adolescents in the HC growth trajectory of consistently above average had higher cognitive scores compared to those with other suboptimal trajectories, while null findings were observed for adolescent emotional and behavioral health. • HC may serve as an inexpensive screening tool to monitor child development at risk during the first 18 months of life, particularly in resource-limited settings.


Asunto(s)
Problema de Conducta , Adolescente , Niño , Desarrollo Infantil , Cognición , Estudios de Cohortes , Cabeza , Humanos , Lactante , Estudios Prospectivos
12.
BMC Pediatr ; 22(1): 738, 2022 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-36577993

RESUMEN

BACKGROUND: Unreasonable use of antibiotics and probiotics can alter the gut ecology, leading to antibiotic resistance and suboptimal health outcomes during early life. Our study aims are to clarify the association among antibiotic and probiotic exposure in early life, the microecology of the gut microbiota, and the development of antibiotic resistance; to investigate the long-term impact of antibiotics and probiotics on the health outcomes of infants and young children; and to provide a theoretical basis for the rational use of antibiotics and probiotics from a life course perspective. METHODS: The study is a prospective, longitudinal birth cohort study conducted in Shaanxi Province, China from 2018 to 2024. A total of 3,000 eligible mother-child pairs will be enrolled from rural, suburban, and urban areas. The recruitment of the participants begins at pregnancy, and the newborns will be followed up for 2 years at successive timepoints: within 3 days after birth, 42 days after birth, and at 3, 6, 12, 18, and 24 months of age. Sociodemographic data, environmental exposures, dietary patterns, psychological conditions, and medical and drug histories are collected. Cognitive and behavioural development among infants and young children and questionnaires on antibiotic knowledge and behaviour among caregivers will be collected at 12 and 24 months of age. The faecal samples are collected and analysed by 16S rRNA high-throughput sequencing and quantitative PCR (qPCR) for antibiotic resistance genes. DISCUSSION: The findings will inform antibiotic and probiotic use for pregnant women and infants and contribute to establishing rational use strategies of antibiotics and probiotics for paediatricians, health practitioners, and drug administration policy-makers. TRIAL REGISTRATION: The study was registered on the Chinese Clinical Trial Registry (ChiCTR) platform, http://www.chictr.org.cn (Record ID: ChiCTR2100047531, June 20, 2021).


Asunto(s)
Microbioma Gastrointestinal , Probióticos , Lactante , Recién Nacido , Humanos , Femenino , Embarazo , Preescolar , Antibacterianos/uso terapéutico , Salud del Lactante , ARN Ribosómico 16S/genética , Estudios Prospectivos , Cohorte de Nacimiento , Estudios de Cohortes , Probióticos/uso terapéutico
13.
Sensors (Basel) ; 22(12)2022 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-35746353

RESUMEN

X-ray fluorescence (XRF) spectroscopy offers a fast and efficient method for analysing soil elemental composition, both in the laboratory and the field. However, the technique is sensitive to spectral interference as well as physical and chemical matrix effects, which can reduce the precision of the measurements. We systematically assessed the XRF technique under different sample preparations, water contents, and excitation times. Four different soil samples were used as blocks in a three-way factorial experiment, with three sample preparations (natural aggregates, ground to ≤2 mm and ≤1 mm), three gravimetric water contents (air-dry, 10% and 20%), and three excitation times (15, 30 and 60 s). The XRF spectra were recorded and gave 540 spectra in all. Elemental peaks for Si, K, Ca, Ti, Fe and Cu were identified for analysis. We used analysis of variance (anova) with post hoc tests to identify significant differences between our factors and used the intensity and area of the elemental peaks as the response. Our results indicate that all of these factors significantly affect the XRF spectrum, but longer excitation times appear to be more defined. In most cases, no significant difference was found between air-dry and 10% water content. Moisture has no apparent effect on coarse samples unless ground to 1 mm. We suggested that the XRF measurements that take 60 s from dry samples or only slightly moist ones might be an optimum option under field conditions.


Asunto(s)
Suelo , Agua , Espectrometría por Rayos X/métodos , Rayos X
14.
Environ Sci Technol ; 54(7): 3840-3848, 2020 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-32119780

RESUMEN

Condensation fine particles (CFPs) from coal-fired flue gas harm humans and the environment after being emitted into the atmosphere. Given their small size (<0.1 µm), difficulty arises in efficiently removing CFPs by wet electrostatic precipitators and mist eliminators. In this work, a laboratory apparatus was used to study the CFP growth under simulated power plant conditions. Four methods were independently investigated to increase the particle size: addition of ammonia, addition of fly ash, decreasing temperature, and applying an electrical discharge. Results demonstrated that the CFP size distribution possessed a unimodal structure with peak at 0.05 µm. At increased ammonia concentration from 10 to 30 ppm, the peak of growth factor shifted rightward and increased from 1.21 to 1.35 and the range of growth factor >1 was significantly broadened due to joint action of multiple mechanisms. Fly ash acted as the core, and CFPs adhered to the ash surface when forming ash-salt droplets. Cooling flue gas could also enhance the CFP growth due to vapor condensation. At decreased temperature from 45 to 30 °C, the median diameter of CFPs increased by 15%. Finally, the growth and agglomeration of CFPs can be further enhanced when an external electrical field was utilized. The size range of growth factor >1 can be broadened, and the peak growth factor significantly increased at 8 kV applied voltage. The research findings provide valuable guidance for effectively improving the CFP removal efficiency by external regulation for growth enhancement.


Asunto(s)
Contaminantes Atmosféricos , Centrales Eléctricas , Atmósfera , Carbón Mineral , Ceniza del Carbón , Humanos , Tamaño de la Partícula
15.
Appl Opt ; 59(27): 8505-8510, 2020 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-32976441

RESUMEN

With the maturity of nano-manufacturing technology, nano-materials with excellent surface-enhanced Raman scattering (SERS) activities have evolved from homogeneous materials to composite ones, but the structural uniformity of composite materials has not been effectively improved. We successfully obtained a series of Ag-Au composite nanostructures with high SERS activity by using a two-step deposition and confined spheroidization process and one-step in-situ substitution method. Anodized alumina templates with uniform size distribution were employed as the initial confined template for spheroidizing Ag film into periodic Ag nanoparticles (Ag NPs). The composite nanostructure was simply obtained after a one-step in-situ galvanic reaction based on the Ag NPs arrays. The results showed that the prepared Ag-Au composite nanostructure could be used as reliable SERS substrates with low relative standard deviation value of ∼6.25% for crystal violet molecules. Compared with previous reports, this one-step route greatly simplifies the process of preparing periodic composite nanomaterials and provides a new idea for constructing multi-component metal nanostructures.

16.
BMC Public Health ; 20(1): 1297, 2020 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-32854672

RESUMEN

BACKGROUND: The epidemiological evidence on the association of sleep quality on anxiety symptoms has been inconclusive. This study aimed to explore the association between sleep quality and anxiety symptoms in rural Chinese population and investigate whether age, lifestyles, and chronic diseases modified this association. METHODS: A total of 27,911 participants aged 18-79 years from the Henan Rural Cohort Study were included in the study. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI) scale. Poor sleep quality was defined as PSQI ≥6. Anxiety symptoms were evaluated with the two-item generalized anxiety disorder scale (GAD-2). Individual with score ≥ 3 was viewed as having anxiety symptoms. Logistic regression and restricted cubic spline were conducted to examine the association of sleep quality with anxiety symptoms. RESULTS: Altogether, 6087 (21.80%) participants were poor sleepers and 1557 (5.58%) had anxiety symptoms. The odds of anxiety were increased with increment of PSQI score after fitting restricted cubic splines. The poor sleep quality was associated with a higher possibility of anxiety symptoms [odd ratio (OR): 4.60, 95% confidence interval (CI): 3.70-5.72] in men, and (OR: 3.56, 95% CI: 3.10-4.09) in women for multivariable analysis. Further, stratified analyses showed that the effect of sleep quality on anxiety symptoms could be modified by age, marital status, smoking status, drinking status, hypertension, and type 2 diabetes mellitus. CONCLUSIONS: A dose-response association between PSQI score and anxiety symptoms was found. In addition, the relationship between poor sleep quality and greater anxiety symptoms was observed in this rural population, especially in participants aged ≥60 years and those with unhealthy habits or had a chronic disease. TRIAL REGISTRATION: The trial was prospectively registered on July 6, 2015 and available online at ClinicalTrials.gov ID: ChiCTR-OOC-15006699 .


Asunto(s)
Ansiedad/epidemiología , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Sueño , Adolescente , Adulto , Distribución por Edad , Anciano , Pueblo Asiatico , China/epidemiología , Enfermedad Crónica/epidemiología , Estudios de Cohortes , Femenino , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Cuestionario de Salud del Paciente , Población Rural , Adulto Joven
17.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(5): 810-817, 2019 Oct 25.
Artículo en Zh | MEDLINE | ID: mdl-31631630

RESUMEN

As a complex system, the topology of human's brain network has an important effect on further study of brain's structural and functional mechanism. Graph theory, a kind of sophisticated analytic strategies, is widely used for analyzing complex brain networks effectively and comparing difference of topological structure alteration in normal development and pathological condition. For the purpose of using this analysis methodology efficiently, it is necessary to develop graph-based visualization software. Thus, we developed VisConnectome, which displays analysis results of the brain network friendly and intuitively. It provides an original graphical user interface (GUI) including the tool window, tool bar and innovative double slider filter, brain region bar, runs in any Windows operating system and doesn't rely on any platform such as Matlab. When importing the user-defined script file that initializes the brain network, VisConnectome abstracts the brain network to the ball-and-stick model and render it. VisConnectome allows a series of visual operations, such as identifying nodes and connection, modifying properties of nodes and connection such as color and size with the color palette and size double slider, imaging the brain regions, filtering the brain network according to its size property in a specific domain as simplification and blending with the brain surface as a context of the brain network. Through experiment and analysis, we conclude that VisConnectome is an effective visualization software with high speed and quality, which helps researchers to visualize and compare the structural and functional brain networks flexibly.


Asunto(s)
Encéfalo/fisiología , Conectoma , Programas Informáticos , Humanos
18.
J Nanosci Nanotechnol ; 18(7): 5054-5058, 2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-29442693

RESUMEN

We have developed a new solution-phase chemical reduction method for the synthesis of poly(vinyl alcohol) coated copper nanoparticles in aqueous solution. Copper nitrate is used as the precursor, sodium hypophosphite as the reducing agent, and poly(vinyl alcohol) as the coating agent. The synthesis of copper nanoparticles could be completed within several hours and the copper nanoparticles in powder form could be stored within one week in ambient condition. In Ar atmosphere, the complete thermal decomposition temperature of coated layer was lower than 450 °C. The antioxidative properties of poly(vinyl alcohol) coated copper nanoparticles were evaluated compared to that of polyvinylpyrrolidone coated copper nanoparticles.

19.
Endocrine ; 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38565797

RESUMEN

BACKGROUND: Thyroid cancer and educational attainment have been related in observational studies. It is unclear if these correlations indicate causative relationships. METHODS: Using large-scale genome-wide association studies (GWAS) datasets, we conducted an univariable and multivariable Mendelian randomization (MR) study to assess a potential connection between educational attainment and thyroid cancer. The inverse-variance weighted (IVW) analysis method is used as our primary outcome. Additionally, we carry out several sensitivity analyses to evaluate the pleiotropy and robustness of the causal estimates. RESULTS: Univariate MR study shows 4.2 years of additional education is associated with a 41.4% reduction in thyroid cancer risk (OR = 0.586; 95% CI: 0.378-0.909; P = 0.017). Further multivariable MR analysis revealed that body mass index (BMI) acted as a partial mediating factor in the protective impact of higher educational attainment against thyroid cancer. CONCLUSION: This MR study provided genetic evidence that longer education attainment is related to a lower risk of thyroid cancer. Strategies of expanding education may reduce the burden of thyroid cancer in the world.

20.
Front Nutr ; 11: 1331172, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38496794

RESUMEN

Background: The effect of micronutrients on thyroid cancer has been studied in observational studies, however, the cause of relationships has not yet been determined. Thyroid cancer was the subject of a Mendelian randomization (MR) analysis of micronutrients. Aimed to determine whether micronutrient intake has a causal impact on the chance of developing thyroid cancer. Methods: We used a Mendelian randomization (MR) analysis with two samples. Our circulation levels of Cu, Ir, Zn, Ca, VD, and VC were reflected by genetic variations reported from GWAS in individuals of European ancestry. For the GWAS outcome of thyroid cancer. Sensitivity studies that included MR-Egger, weighted median/mode tests, and a more open selection of variations at a genome-wide sub-significant threshold were added to our inverse-variance weighted (IVW) MR study. Results: Using the IVW approach, we did not find evidence that any of the micronutrients to thyroid cancer (Cu: odds ratio [OR = 0.88, p = 0.41]; Zn: odds ratio [OR = 0.87, p = 0.40]; Ir: odds ratio [OR = 1.18, p = 0.39]; Ca: odds ratio [OR = 1.12, p = 0.43]; VC: odds ratio [OR = 0.95, p = 0.22]; VD: odds ratio [OR = 0.89, p = 0.04]). The heterogeneity (p > 0.05) and pleiotropy (p > 0.05) testing provided confirmatory evidence for the validity of our MR estimates. Conclusion: This study does not provide evidence that supplementation with micronutrients including Cu, Ir, Zn, Ca, VD, and VC can prevent thyroid cancer.

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