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Iodine, an essential trace element for the human body, plays a pivotal role in sustaining health. Malnutrition has emerged as a pressing public health concern, posing a significant threat to human well-being. Iodine deficiency poses a substantial threat to the development of children, potentially leading to neurological developmental disorders and mental retardation. Conversely, excessive iodine intake can result in structural and functional abnormalities in the thyroid gland. In this study, we selected children aged 3-6 years through a stratified cluster sampling approach in six regions across China to explore the correlation between iodine nutrition and their physical growth. A total of 5920 preschool children participated in this study, with a median urinary iodine concentration (UIC) of 177.33 [107.06, 269.92] µg/L. Among these children, 250 (4.2%) exhibited stunting, 180 (3.0%) were underweight, 198 (3.3%) experienced wasting, 787 (3.3%) were overweight and 414 (7.0%) were classified as obese. The multivariate linear regression revealed that UIC exhibited a positive correlation with body mass index z-Score (BMIZ) in overweight children (ß = 0.038; 95% CI: 0.001, 0.075). In normally growing children, the associations between UIC and height-for-age z-score, weight-for-age z-score and BMIZ displayed nonlinear patterns. Our findings suggest that iodine nutrition is adequate for Chinese children aged 3-6 years. Furthermore, iodine nutrition is intricately linked to the growth and development of these children. Consequently, it is imperative to implement decisive measures to prevent both iodine deficiency and excess.
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Background: Artificial intelligence (AI) chatbots, such as ChatGPT-4, have shown immense potential for application across various aspects of medicine, including medical education, clinical practice, and research. Objective: This study aimed to evaluate the performance of ChatGPT-4 in the 2023 Taiwan Audiologist Qualification Examination, thereby preliminarily exploring the potential utility of AI chatbots in the fields of audiology and hearing care services. Methods: ChatGPT-4 was tasked to provide answers and reasoning for the 2023 Taiwan Audiologist Qualification Examination. The examination encompassed six subjects: (1) basic auditory science, (2) behavioral audiology, (3) electrophysiological audiology, (4) principles and practice of hearing devices, (5) health and rehabilitation of the auditory and balance systems, and (6) auditory and speech communication disorders (including professional ethics). Each subject included 50 multiple-choice questions, with the exception of behavioral audiology, which had 49 questions, amounting to a total of 299 questions. Results: The correct answer rates across the 6 subjects were as follows: 88% for basic auditory science, 63% for behavioral audiology, 58% for electrophysiological audiology, 72% for principles and practice of hearing devices, 80% for health and rehabilitation of the auditory and balance systems, and 86% for auditory and speech communication disorders (including professional ethics). The overall accuracy rate for the 299 questions was 75%, which surpasses the examination's passing criteria of an average 60% accuracy rate across all subjects. A comprehensive review of ChatGPT-4's responses indicated that incorrect answers were predominantly due to information errors. Conclusions: ChatGPT-4 demonstrated a robust performance in the Taiwan Audiologist Qualification Examination, showcasing effective logical reasoning skills. Our results suggest that with enhanced information accuracy, ChatGPT-4's performance could be further improved. This study indicates significant potential for the application of AI chatbots in audiology and hearing care services.
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Inteligencia Artificial , Audiólogos , Audiología , Humanos , Taiwán , Audiología/métodos , Evaluación Educacional/métodos , Masculino , Competencia Clínica/normas , FemeninoRESUMEN
Small particles that are trapped, deposited, or otherwise fixed can be imaged by digital holography with a resolution approaching that of optical microscopy. When such particles are in motion as an aerosol, a comparable resolution is challenging to achieve. Using a simplified bi-telecentric lens system, we demonstrate that 1µm free-flowing aerosol particles can be imaged at the single-particle level using digital in-line holography. The imaging is demonstrated with an aerosol of 1µm polystyrene latex microspheres and a ragweed pollen aerosol.
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OBJECTIVE: The morphology and functions of the human trabecular meshwork (HTM) are dysregulated in glaucoma, and the molecular mechanisms of this dysregulation remain unknown. According to an established in vitro model, whose function was to study the regulatory networks sustaining the response of HTM cells to the increased substrate stiffness, we systematically analyzed the expression pattern of long noncoding RNAs (lncRNAs), the important regulatory RNAs in cells. METHODS: Bioinformatics analysis was performed to identify the dysregulated lncRNAs in response to increased substrate stiffness using transcriptome sequencing data (RNA-seq). Then we interfered with the expression of several dysregulated lncRNAs in HTM cells to explore their molecular targets. The cross-linking immunoprecipitation and sequencing method (CLIP-seq) was used to identify enhancer of zeste homolog 2 (EZH2)-targeted RNAs in HTM cells. The chromatin IP and sequencing method (ChIP-seq) was used to identify the targets of EZH2 and histone H3 at lysine 27 (H3K27me3). RESULTS: The response of thousands of dysregulated lncRNAs to increased substrate stiffness was identified through RNA-seq. Functional prediction of these lncRNAs revealed that they potentially regulated key biological processes, including extracellular matrix (ECM) organization. By interfering with the expression of lncRNA SHNG8, ZFHX4-AS1, and RP11-552M11.4, the results demonstrated that those lncRNAs extensively regulated the expression levels of ECM-associated genes. Moreover, we found that EZH2 expression was significantly decreased at high substrate stiffness. Using CLIP-seq to identify EZH2-targeted RNAs in HTM cells, we found that SNHG8 was bound by EZH2. According to the CLIP-seq data of EZH2, we found that EZH2 binding sites were observed in the transcripts of SNHG8-regulated genes, but not in the ChIP-seq results of EZH2 and H3K27me3. CONCLUSION: Our results suggest that SNHG8 and EZH2 may cooperate to regulate the expression of a subset of genes by influencing their RNA abundance, explaining how they support HTM cell morphology and high density. This study contributes to the understanding of the alteration of HTM during the progression of glaucoma by identifying functional lncRNAs, especially SNHG8, and suggests novel therapeutic targets to treat glaucoma.
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Glaucoma , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Histonas/metabolismo , Transcriptoma , Malla Trabecular/metabolismo , Cromatina/metabolismo , Biología Computacional/métodos , Glaucoma/genética , Glaucoma/metabolismoRESUMEN
There has been an upward trend in the incidence of glioma, with high recurrence and high mortality. The beta subunits of the 20S proteasome are encoded by the proteasome beta (PSMB) genes and may affect the proteasome's function in glioma, assembly and inhibitor binding. This study attempted to reveal the function of the proliferation and invasion of glioma cells, which is affected by proteasome 20S subunit beta 2 (PSMB2). We subjected the data downloaded from the TCGA database to ROC, survival, and enrichment analyses. After establishing the stable PSMB2 knockdown glioma cell line. We detect the changes in the proliferation, invasion and migration of glioma cells by plate colony formation assay, transwell assay, wound healing assay and flow cytometry and PSMB2 expression was verified by quantitative PCR and Western blotting to identify the mRNA and protein levels. PSMB2 expression was higher in glioma tissues, and its expression positively correlated with poor prognosis and high tumor grade and after PSMB2 knockdown, the proliferation, invasion and migration of glioma cells were weakened.
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Neoplasias Encefálicas , Glioma , Humanos , Neoplasias Encefálicas/patología , Complejo de la Endopetidasa Proteasomal/genética , Proliferación Celular/genética , Glioma/patología , Línea Celular Tumoral , Movimiento Celular/genética , Microambiente Tumoral/genéticaRESUMEN
Phenols such as bisphenols, parabens, and triclosan are common environmental endocrine disruptors. Previous epidemiological studies have suggested that phenols may affect semen quality, but the results were inconsistent. In addition, most existing studies have been limited to the effects of a single chemical compound, ignoring the health effects of mixed exposure to multiple chemicals. Thus, we aimed to explore the associations between individual and mixed exposure to phenols and various semen quality parameters. In this study, a rapid and sensitive method was used to determine 18 phenolic compounds in urine samples of 799 volunteers who donated sperm samples to the Shanghai Human Sperm Bank. A spot urine sample was collected from each subject on the day of their clinic visit and stored at -20 â until testing. Urine samples (200 µL) were extracted and added with 20 µL of an internal standard and 50 µL of ß-glucuronidase solution. The mixtures were then incubated for 12 h at 37 â. After hydrolysis, the samples were extracted twice using ethyl acetate (500 µL). The concentrations of the 18 phenolic compounds were measured using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Semen quality parameters were analyzed using a computer-aided semen analyzer. Multiple linear regressions were used to detect the associations between individual phenol exposure and semen quality parameters. In addition, weighted quantile sum (WQS) models were used to explore the associations between mixed-phenol exposure and semen quality parameters. After adjusting for potential covariates, the results of multiple linear regressions showed that exposure to ethyl paraben (EtP) was significantly negatively associated with sperm concentration and total sperm count (P<0.05). In addition, exposure to mixed phenols was significantly associated with decreased sperm concentration; methyl paraben (MeP) and EtP were identified as the main contributors to this decrease. Thus, phenol exposure may be associated with decreased semen quality in young males, particularly with respect to sperm concentration and total sperm count.
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Parabenos , Fenol , Análisis de Semen , Humanos , Masculino , Semen , Espectrometría de Masas en Tándem/métodos , China , Fenoles/orinaRESUMEN
Largely driven by agricultural pressures, biodiversity has experienced great changes globally. Exploring biodiversity responses to agricultural practices associated with agricultural intensification can benefit biodiversity conservation in agricultural landscapes. However, the effects of agricultural practices may also extend to natural habitats. Moreover, agricultural impacts may also vary with geographical region. We analyze biodiversity responses to landscape cropland coverage, cropping frequency, fertiliser and yield, among different land-use types and across geographical regions. We find that species richness and total abundance generally respond negatively to increased landscape cropland coverage. Biodiversity reductions in human land-use types (pasture, plantation forest and cropland) were stronger in tropical than non-tropical regions, which was also true for biodiversity reductions with increasing yield in both human and natural land-use types. Our results underline substantial biodiversity responses to agricultural practices not only in cropland but also in natural habitats, highlighting the fact that biodiversity conservation demands a greater focus on optimizing agricultural management at the landscape scale.
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Conservación de los Recursos Naturales , Ecosistema , Humanos , Conservación de los Recursos Naturales/métodos , Biodiversidad , Bosques , Agricultura/métodos , Productos AgrícolasRESUMEN
Of the 12 wild felid species found in China, Asiatic golden cat (Catopuma temminckii) is one of the least studied species. This medium-sized cat with a prominently polymorphic coat was once distributed across much of southern China, but is believed to have experienced severe decline and range contraction during the past decades, primarily due to anthropogenic pressures. A lack of knowledge of its current distribution, ecology, and natural history has greatly hindered the implementation of conservation and management actions for this species. In this study, for the first time, we compiled the state-wide occurrence records (N = 409), mainly from the camera-trapping surveys, of Asiatic golden cats from 2008 to 2019, and predicted its distribution across the country through species distribution modeling using random forest algorithm. The results showed that the predicted habitats were mainly located in southwest China and suggested a rather low probability of possible current distribution across its vast historic range in central, eastern, and southern China. We divided its current range into four geographic regions (i.e., Qinling Mountains, Hengduan Mountains, East Himalayas, and southern Yunnan region) and considered the cats in each region as a regional population within the country. From the 287 camera-trapping detections with photographs and/or videos collected across all populations, we identified six coat morphs and determined their occurrence percentages: common golden (47.4%), spotted (20.9%), red (13.6%), dark cinnamon (10.1%), melanistic (7.0%), and gray (1.0%). The complexity of coat morph composition within regional populations showed an increasing gradient from northeast to southwest. Among the four regional populations, the East Himalayas hosted the highest abundance and coat variation with all six morphs recorded. Our study results update the current distribution and coat morphology variations of this elusive cat in China and provide important knowledge to guide future research and conservation planning for this threatened species.
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INTRODUCTION: The use of the neodymium:yttrium-aluminum-garnet (Nd:YAG) laser to treat malignant glaucoma (MG) has been described in the literature since the 1980s. However, the technique has been reported to have a short-term effect, with a notable relapse rate. In the present study, we report the efficacy and durability of a modified Nd:YAG laser treatment methodology for treatment of pseudophakic or aphakic MG. METHODS: Patients with chronic angle-closure glaucoma and deemed at high risk of developing post-operative MG received prophylactic peripheral iridectomy during their conventional operation beginning in 2017. When the diagnosis of pseudophakic or aphakic MG was confirmed, a thorough Nd:YAG laser capsulo/zonulo-hyaloido-vitreolysis (CZHV) was performed through iridectomy, along with standardized pre- and post-laser medications. This retrospective case series includes 14 eyes of 11 patients with MG who had surgical preset iridectomy and modified Nd:YAG laser CZHV between 2017 and 2022. Outcome measures included resolution and recurrence of MG and incidence of treatment complications. RESULTS: The mean follow-up was 27.1 ± 15.0 months (range, 12-48). Long-term resolution of MG was obtained in all included eyes at the end of the follow-up. Six eyes (42.9%) achieved long-term resolution with a single Nd:YAG laser intervention. Eight eyes (57.1%) achieved long-term resolution following two to three laser interventions, with two eyes (14.3%) experiencing recurrence. There was no complication during the follow-up. At the final visit, a significant reduction (P = 0.0001) in the mean intraocular pressure (IOP) was observed (13.1 ± 2.8 mmHg) compared to presentation (21.4 ± 6.3 mmHg). CONCLUSION: The modified Nd:YAG laser treatment methodology is a minimally invasive option to manage pseudophakic or aphakic MG with sustained effectiveness. Reduced inflammatory reactions due to prophylactic peripheral iridectomy, rapid diagnosis, and timely treatment initiation have all contributed to the favorable outcomes associated with this modified treatment methodology.
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BACKGROUND: Manganese (Mn) overexposure can induce neurotoxicity and lead to manganism. Vitamin E (Vit E) has neuroprotective effects by acting as an ROS scavenger, preventing mitochondrial dysfunction and neuronal apoptosis. However, the effects of Vit E on Mn-induced nigrostriatal system lesions remains unknown. OBJECTIVES: We aim to investigate whether Vit E has protective effects on Mn-induced nigrostriatal system lesions and mRNA expression profiles in the SN of mice. METHODS: Sixty 8-week-old C57BL/6 male mice were randomly divided into the Control, MnCl2, MnCl2 +Vit E, and Vit E group. Twenty-four hours after the last injection, the behaviour test was performed. The numbers of dopaminergic neurons in Substantia nigra (SN), the contents of dopamine and its metabolite levels in striatium, and the morphology of mitochondria and nuclei in the dopaminergic neurons in SN were detected by immunofluorescence staining, high-performance liquid chromatography, and transmission electron microscopy. Transcriptome analysis was used to analyze the signaling pathways and RT-PCR was used to verify the mRNA levels. RESULTS: Vit E ameliorates behavioral disorders and attenuates the loss of nigral dopaminergic neurons in the Mn-induced mouse model. In addition, Vit E antagonized Mn-induced toxicity by restoring mitochondrial function. The results of transcriptome sequencing and RTPCR show that the protective effect of Vit E was related to the upregulation of CHRM1 and KCNJ4 mRNA in the SN. CONCLUSIONS: Vit E has neuroprotective effects on Mn-induced neurodegeneration in the nigrostriatal system. This effect may be related to the upregulation of CHRM1 and KCNJ4 mRNA stimulated by Vit E in the SN.
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Neuronas Dopaminérgicas , Intoxicación por Manganeso , Manganeso , Fármacos Neuroprotectores , Vitamina E , Animales , Masculino , Ratones , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/patología , Manganeso/toxicidad , Intoxicación por Manganeso/prevención & control , Ratones Endogámicos C57BL , Fármacos Neuroprotectores/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Vitamina E/farmacologíaRESUMEN
Inhibition of the Embryonic Ectoderm Development (EED) subunit in Polycomb Repressive Complex 2 (PRC2) can inhibit tumor growth. In this paper, we selected six experimentally designed EED competitive Inhibitors of the triazolopyrimidine derivatives class. We investigated the difference in the binding mode of the natural substrate to the Inhibitors and the effects of differences in the parent nuclei, heads, and tails of the Inhibitors on the inhibitory capacity. The results showed that the binding free energy of this class of Inhibitors was close to or lower compared to the natural substrate, providing an energetic basis for competitive inhibition. For the Inhibitors, the presence of a strong negatively charged group at the 6-position of the parent nucleus or the 8'-position of the head would make the hydrogen atom on the head imino group prone to flip, resulting in the vertical movement of the parent nucleus, which significantly decreased the inhibitory ability. When the 6-position of the parent nucleus was a nonpolar group, the parent nucleus would move horizontally, slightly decreasing the inhibitory ability. When the 8'-position of the head was methylene, it formed an intramolecular hydrophobic interaction with the benzene ring on the tail, resulting in a significant increase in inhibition ability.
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Ectodermo , Simulación de Dinámica Molecular , Ectodermo/metabolismo , Complejo Represivo Polycomb 2/química , Complejo Represivo Polycomb 2/metabolismoRESUMEN
Large increases in the number of low earth orbit satellites are projected in the coming decades [L. Schulz, K.-H. Glassmeier, Adv. Space Res. 67, 1002-1025 (2021)] with perhaps 50,000 additional satellites in orbit by 2030 [GAO, Large constellations of satellites: Mitigating environmental and other effects (2022)]. When spent rocket bodies and defunct satellites reenter the atmosphere, they produce metal vapors that condense into aerosol particles that descend into the stratosphere. So far, models of spacecraft reentry have focused on understanding the hazard presented by objects that survive to the surface rather than on the fate of the metals that vaporize. Here, we show that metals that vaporized during spacecraft reentries can be clearly measured in stratospheric sulfuric acid particles. Over 20 elements from reentry were detected and were present in ratios consistent with alloys used in spacecraft. The mass of lithium, aluminum, copper, and lead from the reentry of spacecraft was found to exceed the cosmic dust influx of those metals. About 10% of stratospheric sulfuric acid particles larger than 120 nm in diameter contain aluminum and other elements from spacecraft reentry. Planned increases in the number of low earth orbit satellites within the next few decades could cause up to half of stratospheric sulfuric acid particles to contain metals from reentry. The influence of this level of metallic content on the properties of stratospheric aerosol is unknown.
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BACKGROUND: Parabens are common preservatives in personal care products, cosmetics, and medical goods. In the past few years, animal studies showed the male reproductive toxicity associated with some parabens. Yet, epidemiological studies have generated inconsistent findings and research rarely has focused on the mixture effects of the parabens. We aimed to explore the associations between individual paraben exposure as well as the mixture and semen quality parameters. METHODS: A total of 795 male partners from preconception couples were included in the study. Their urine samples were analyzed for the concentrations of six parabens, namely methyl paraben (MeP), ethyl paraben (EtP), propyl paraben (PrP), butyl paraben (BuP), benzyl paraben (BzP) and heptyl paraben (HeP). Multiple linear regression models and weighted quantile sum regression (WQS) models were utilized to assess the relationships between individual paraben exposure and paraben mixture with semen quality parameters, respectively. RESULTS: After adjusting for covariates, exposure to a paraben mixture was significantly associated with declining sperm concentration, total sperm count, and progressive motility, among which BuP was identified as the main contributor to sperm concentration and total sperm count while MeP to progressive motility. Results from multiple linear regression models were generally in line with the WQS analysis. CONCLUSIONS: Our results suggest negative associations between paraben mixture and sperm concentration, total sperm count, and sperm motility among reproductive-aged men.
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Parabenos , Análisis de Semen , Animales , Masculino , Humanos , Adulto , Parabenos/toxicidad , Motilidad Espermática , SemenRESUMEN
Objective: This study aims to develop and evaluate a non-imaging clinical data-based nomogram for predicting the risk of vision-threatening diabetic retinopathy (VTDR) in diabetes mellitus type 2 (T2DM) patients. Methods: Based on the baseline data of the Guangdong Shaoguan Diabetes Cohort Study conducted by the Zhongshan Ophthalmic Center (ZOC) in 2019, 2294 complete data of T2DM patients were randomly divided into a training set (n=1605) and a testing set (n=689). Independent risk factors were selected through univariate and multivariate logistic regression analysis on the training dataset, and a nomogram was constructed for predicting the risk of VTDR in T2DM patients. The model was evaluated using receiver operating characteristic (ROC) curves and area under the curve (AUC) in the training and testing datasets to assess discrimination, and Hosmer-Lemeshow test and calibration curves to assess calibration. Results: The results of the multivariate logistic regression analysis showed that Age (OR = 0.954, 95% CI: 0.940-0.969, p = 0.000), BMI (OR = 0.942, 95% CI: 0.902-0.984, p = 0.007), systolic blood pressure (SBP) (OR =1.014, 95% CI: 1.007-1.022, p = 0.000), diabetes duration (10-15y: OR =3.126, 95% CI: 2.087-4.682, p = 0.000; >15y: OR =3.750, 95% CI: 2.362-5.954, p = 0.000), and glycated hemoglobin (HbA1C) (OR = 1.325, 95% CI: 1.221-1.438, p = 0.000) were independent risk factors for T2DM patients with VTDR. A nomogram was constructed using these variables. The model discrimination results showed an AUC of 0.7193 for the training set and 0.6897 for the testing set. The Hosmer-Lemeshow test results showed a high consistency between the predicted and observed probabilities for both the training set (Chi-square=2.2029, P=0.9742) and the testing set (Chi-square=7.6628, P=0.4671). Conclusion: The introduction of Age, BMI, SBP, Duration, and HbA1C as variables helps to stratify the risk of T2DM patients with VTDR.
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Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Humanos , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/etiología , Estudios de Cohortes , Hemoglobina Glucada , Diabetes Mellitus Tipo 2/complicaciones , Factores de RiesgoRESUMEN
Per- and polyfluoroalkyl substances (PFAS) are persistent, ubiquitous pollutants, and the current epidemiological evidence regarding the impact of in utero exposure to PFAS on anogenital distance (AGD) is limited and inconclusive. The primary aim of this study was to investigate the potential associations between maternal exposure to PFAS during pregnancy and AGD in newborns. A total of 2273 mother-child pairs were recruited for this study, and both PFAS levels and AGD were measured. Multiple linear regression models were utilized to explore the relationships between individual PFAS and AGD. Additionally, quantile-based g-computation (QGC) was employed to assess the joint effects of mixtures of PFAS on AGD. Our findings showed that maternal exposure to PFOS (ß = 0.518, 95% CI: 0.093, 0.942), PFNA (ß = 0.487, 95% CI: 0.037, 0.937), PFDA (ß = 0.443, 95% CI: 0.048, 0.838), PFUA (ß = 0.434, 95% CI: 0.031, 0.838), and PFBS (ß = 0.444, 95% CI: 0.124, 0.763) during early pregnancy had a significant positive association with AGD in boys. Similarly, in girls, maternal exposure to PFOS (ß = 0.423, 95% CI: 0.006, 0.841), PFNA (ß = 0.641, 95% CI: 0.207, 1.074), PFDA (ß = 0.670, 95% CI: 0.306, 1.033), PFUA (ß = 0.895, 95% CI: 0.509, 1.281), and PFBS (ß = 0.474, 95% CI: 0.178, 0.770) had a positive association with AGD, while PFOA (ß = -1.254, 95% CI: -1.786, -0.723) had a negative association. QGC models further confirmed that PFAS mixtures were positively associated with AGD. Moreover, PFBS was the primary contributor to the joint effects of PFAS mixtures on AGD. In summary, our study has provided further corroboration for the possibility that PFAS exposure can have an impact on AGD in both boys and girls. The use of AGD as a promising biomarker for endocrine disruption highlights the significance of our findings, which may have valuable clinical implications for reproductive diseases.
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Ácidos Alcanesulfónicos , Contaminantes Ambientales , Fluorocarburos , Masculino , Embarazo , Femenino , Humanos , Recién Nacido , Estudios Prospectivos , Exposición a Riesgos Ambientales , Exposición MaternaRESUMEN
BACKGROUND: Previous studies have reported that ambient temperature may affect perinatal outcomes. However, whether extreme temperature affects the risk of preterm birth (PTB) remains controversial. Studies on the associations of extreme temperature with PTB subtypes are lacking. OBJECTIVES: We aimed to investigate the associations of extreme climate events with the risks of PTB and its subtypes, discerning possible modifiers. METHODS: Data on all singleton deliveries were obtained from the China Labor and Delivery Survey (CLDS), a nationwide investigation implemented in 2015 and 2016. PTB was defined as gestational weeks <37 and then categorized as early (24-34 wk) and late PTBs (35-36 wk), and clinical subtypes [spontaneous PTB, preterm premature rupture of the fetal membranes (PPROM), iatrogenic PTB]. Ambient temperature data were provided by the China National Weather Data Sharing System. Five heat indexes and five cold indexes were used to define heat waves and cold spells. Generalized linear mixed models with a random term by hospital unit were used to assess the associations of short-term prenatal extreme temperature exposure. The Cox proportional hazard regression model was applied to assess the nonlinear associations of low- or high-temperature exposure at the whole and different trimesters of pregnancy with the risk of PTB. Stratified analyses were conducted to assess the possible modification by geographic region and fetal sex. RESULTS: A total of 70,818 singleton births from 96 hospitals in China were included, among which 4,965 (7.01%) were PTBs. Exposure to extreme cold events 1 wk before delivery was associated with an increased PTB risk, with an adjusted odds ratio (aOR) [95% confidence intervals (CIs)] of 1.07 (95% CI: 1.04, 1.10) and 1.06 (1.04, 1.09) for the total days when the daily average temperature below the fifth percentile (fifth-days) and the 10th percentile (10th-days), 1.18 (1.04, 1.34) for the cold spells when the daily average temperature below the fifth percentile for two consecutive days (fifth-2D), 1.09 (1.03, 1.16) and 1.12 (1.06, 1.19) for the cold spells when the daily average temperature below the 10th percentile for three and two consecutive days (10th-3D and 10th-2D), respectively. Results of extreme temperature exposure during 2 weeks before delivery showed similarly significant associations. The association between cold spells and PTB tended to be stronger for late PTB than for early PTB. Cold spells were mainly associated with spontaneous PTB and late PPROM. A stratified analysis indicated that pregnant women in western and northern regions tended to be more sensitive to cold spells, and pregnant women with a female fetus appeared to be at a higher risk of PTB when exposed to cold spells. Pregnant women in late pregnancy were more susceptible to extreme temperatures. No significant or stable association was found between heat waves and preterm birth. DISCUSSION: Exposure to cold spells was associated with an increased risk of PTB, especially late, spontaneous PTB and PPROM. The associations appeared to be more pronounced in the north and west regions and in pregnancies with female fetuses. https://doi.org/10.1289/EHP10831.
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Rotura Prematura de Membranas Fetales , Nacimiento Prematuro , Embarazo , Humanos , Femenino , Recién Nacido , Nacimiento Prematuro/epidemiología , Temperatura , China/epidemiologíaRESUMEN
Myanmar is one of the most biodiverse countries in the Asia-Pacific region due to a wide range of climatic and environmental heterogeneity. Floristic diversity in Myanmar is largely unknown, resulting in a lack of comprehensive conservation plans. We developed a database of higher plants in Myanmar derived from herbarium specimens and literature sources, and analyzed patterns of diversity inventories and collection inconsistencies, aiming to provide a baseline floristic data of Myanmar and act as a guide for future research efforts. We collected 1,329,354 records of 16,218 taxa. Results show that the collection densities at the township level was variable, with 5% of townships having no floristic collections. No ecoregion had an average collection density of greater than 1 specimen/km2 and the lowest collection density was found in the Kayah-Karen Montane Rainforests, which covered 8% of Myanmar's total area. The highest sampling densities were found in Mandalay Region, Chin State, and Yangon Region. Despite floristic collections over the past three centuries, knowledge of the distribution of the vast majority of plant taxa remained limited, particularly for gymnosperms, pteridophytes, and bryophytes. More botanical surveys and further analyses are needed to better describe Myanmar's floristic diversity. An important strategy to promote knowledge of the biodiversity patterns in Myanmar is to improve the collection and digitalization of specimens and to strengthen cooperation among countries.