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The limited anthropogenic activities on the Tibetan Plateau make this an ideal natural laboratory to elucidate how climate change impacts lake changes. Previous studies have mainly focused on decadal lake changes, yet their rapid evolutions at short temporal intervals and the associated atmospheric origins remain elusive. Here, we produce a new lake area change dataset at monthly sampling over 2015-2020 from 16,801 satellite images. Our estimates achieve an accuracy of <30 m, as evidenced by in-situ GPS field survey validations of representative lake shorelines. We found contrasting patterns in recent rapid area changes: deaccelerating in the north and accelerating in the south. Such contrasting pattern was unprecedented in the last two decades and is likely caused by recent precipitation anomalies, indicating that lakes in TP may experience a tipping point. Lakes are found to store only a small portion (<5 %) of net precipitation in summer, increased to â¼11 % for years with heavy precipitation, which helps understand the water mass budget for lakes over there. Our study highlights the importance of investigating short-term lake area changes as a climate proxy to study their rapid responses to intra- and inter-annual climate variability.
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Grassland degradation decreases ecosystem productivity and diminishes soil biodiversity, leading to the loss of beneficial microorganisms. Arbuscular mycorrhizal fungi (AMF) play a critical role in ecosystem functioning, being a key link between plant and microbial communities, soil, and vegetation. Here, we evaluated the potential of increasing the productivity of degraded grassland by AMF inoculation. A gradient of soil biodiversity: complete sterilization, low, moderate, and high biodiversity was established using the dilution-to-extinction approach. Grassland microcosms under greenhouse conditions were inoculated with three AMF taxa in an increasing diversity: no AMF, single AMF taxa, and all three AMF taxa together. The loss of soil biodiversity decreased plant community productivity, primarily due to reduced biomass of legumes and non-N2-ï¬xing forbs. AMF inoculation raised plant community productivity by 190%, mainly attributed to the greater biomass of legumes and non-N2-fixing forbs. This positive effect of AMF inoculation was particularly pronounced on soils with low biodiversity, where soil mutualists were absent. The biomass of grasses remained independent of AMF inoculation. This differential responsiveness to mycorrhiza was mainly due to the distinctive plant traits of each plant functional group. Inoculating with a single AMF was more beneficial for plant biomass production than inoculation with multiple AMF under lower levels of soil biodiversity, probably due to high functional redundancy among AMF taxa. In conclusion, AMF inoculation reduced the adverse impact of soil degradation and biodiversity loss on plant biomass and vegetation development, highlighting the key roles and importance of AMF for grassland restoration.
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Cadmium contamination in saline-alkali soil is becoming a great concern. Combined microbe-plant remediation is an economic way to treat this contamination, but is compromised by its low cadmium-removing capacity. In this study, the novel fungus-derived biochar was prepared to enhance the salt-tolerant bacterium-plant remediation of cadmium-contaminated saline-alkali soil. This biochar was prepared by pre-incubation of living Trichoderma atroviride hyphae with imidazole and further heating at 500 °C for 1 h. The obtained fungus-derived nitrogen-doped biochar (FBioCN) exhibited the high affinity to bacterial cells, leading to efficient colonization of exogenous salt-tolerant bacteria (e.g., Rhizobacter sp. and Sphingomonas sp.) on Amaranthus hypochondriacus roots. During culturing of the plants in the cadmium-contaminated saline-alkali soil, FBioCN drastically remodeled the rhizosphere microbiome, leading to enhance colonization of the exogeneous salt-tolerant bacteria, and increase bacterial diversity. The combination of FBioCN and the exogeneous bacteria further improved the activity of rhizosphere functional enzymes, protected the plants from the multiple stress, and promoted cadmium transport from the soil to the plants. Consequently, FBioCN together with the salt-tolerant bacteria drastically improved cadmium removal from the saline-alkali soil, with the percent of cadmium removal at the rhizosphere region increasing from 35.1% to 95.1%. This study sheds a light on the application of fungus-derived biochar in combined microbe-plant remediation in saline-alkali soil.
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Cádmio , Poluentes do Solo , Cádmio/análise , Álcalis , Solo , Poluentes do Solo/análise , Bactérias , Fungos , Micélio/químicaRESUMO
Little is known about the association of ambient ozone with ovarian reserve. Based on a retrospective cohort study of 6008 women who attended a fertility center in Hubei, China, during 2018-2021, we estimated ozone exposure levels by calculating averages during the development of follicles (2-month [W1], 4-month [W2], 6-month [W3]) and 1-year before measurement (W4) according to Tracking Air Pollution in China database. We used multivariate logistic regression and linear regression models to investigate association of ozone exposure with anti-müllerian hormone (AMH), the preferred indicator of ovarian reserve. Each 10 µg/m3 increases in ozone were associated with 2.34% (0.68%, 3.97%), 2.08% (0.10%, 4.01%), 4.20% (1.67%, 6.67%), and 8.91% (5.79%, 11.93%) decreased AMH levels during W1-W4; AMH levels decreased by 15.85%, 11.90%, 16.92% in the fourth quartile during W1, W3, and W4 when comparing the extreme quartile, with significant exposure-response relationships during W4 (P < 0.05). Ozone exposure during W1 was positively associated with low AMH. Additionally, we detected significant effect modification by age, body mass index, and temperature in ozone-associated decreased AMH levels. Our findings highlight the potential adverse impact of ozone pollution on female ovarian reserve, especially during the secondary to small antral follicle stage and 1-year before measurement.
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Reserva Ovariana , Ozônio , Feminino , Humanos , Estudos Retrospectivos , População do Leste Asiático , Folículo Ovariano/fisiologia , Hormônio Antimülleriano/fisiologiaRESUMO
OBJECTIVE: To examine for the in vitro existence of contractile nodules on the taut band of muscle fibers where myofascial trigger points (MTrPs) are located (using cell culture). METHODS: Sixteen male Sprague-Dawley rats (7 weeks old) were randomly divided into experimental and control groups. A blunt striking injury and eccentric exercise were applied to the gastrocnemius muscle of rats in the experimental group once a week for 8 weeks to establish an MTrP model. Subsequently, the rats were reared normally and rested for 4 weeks. After modeling, the skeletal muscles at the MTrPs (and non-MTrPs at the same anatomical position) were extracted from the two groups of rats for in vitro cell culture experiments of single muscle fibers. Potential contractile nodules in the MTrP group were exposed to different concentrations of acetylcholinesterase, whereas non-MTrP cells were exposed to acetylcholine. The morphological changes of muscle cells in each group were observed. RESULTS: By culturing MTrP cells in vitro, large contractile nodules remained in single MTrP muscle fibers, whereas some contractile nodules were twisted and deformed. After the addition of different acetylcholinesterase concentrations, no obvious morphological changes were observed in the contractile nodules in the MTrP group. After the non-MTrP cells were exposed to different acetylcholine concentrations, no significant morphological changes were observed in the single muscle fibers. CONCLUSION: MTrP cells can continue to maintain contractile morphology in vitro, but whether the recovery of such contractile nodules is related to acetylcholine remains uncertain.
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PURPOSE: Streptococcus pneumoniae (Spn) is a major cause of child death. We investigated the epidemiology of S. pneumoniae in a pediatric fever clinic and explored the genomics basis of the limited vaccine response of serotype 14 strains worldwide. METHODS: Febrile disease and pneumonia were diagnosed following criteria from the WHO at the end of 2019 at a tertiary children's hospital. Spn was isolated by culture from nasopharyngeal (NP) swabs. The density was determined by lytA-base qPCR. Isolates were serotyped by Quellung and underwent antimicrobial susceptibility testing. Whole-genome sequencing was employed for molecular serotyping, MLST, antibiotic gene determination, SNP calling, recombination prediction, and phylogenetic analysis. RESULTS: The presence of pneumococcus in the nasopharynx (87.5%, 7/8, p = 0.0227) and a high carriage (100%, 7/7, p = 0.0123) were significantly associated with pneumonia development. Living with siblings (73.7%, 14/19, p = 0.0125) and non-vaccination (56.0%, 28/50, p = 0.0377) contributed significantly to the Spn carriage. Serotype 14 was the most prevalent strain (16.67%, 5/30). The genome analysis of 1497 serotype 14 strains indicated S14/ST876 strains were only prevalent in China, presented limited vaccine responses with higher recombination activities within its cps locus, and unique variation patterns in the genes wzg and lrp. CONCLUSION: With the lifting of the one-child policy, it will be crucial for families with multiple children to get PCV vaccinations in China. Due to the highly variant cps locus and distinctive variation patterns in capsule shedding and binding proteins genes, the prevalent S14/ST876 strains have shown poor response to current vaccines. It is necessary to continue monitoring the molecular epidemiology of this vaccine escape clone.
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Importance: To date, the diagnostic test completion rate and the time to diagnostic endoscopy or colonoscopy among adults with iron-deficiency anemia (IDA) and/or hematochezia have not been well characterized. Objective: To evaluate the diagnostic test completion rate and the time to diagnostic testing among veterans younger than 50 years with IDA and/or hematochezia. Design, Setting, and Participants: This cohort study was conducted within the Veterans Health Administration between October 1, 1999, and December 31, 2019, among US veterans aged 18 to 49 years from 2 separate cohorts: those with a diagnosis of IDA (n = 59â¯169) and those with a diagnosis of hematochezia (n = 189â¯185). Statistical analysis was conducted from August 2021 to August 2023. Exposures: Diagnostic testing factors included age, sex, race and ethnicity, Veterans Health Administration geographic region, and hemoglobin test value (IDA cohort only). Main Outcomes and Measures: Primary outcomes of diagnostic testing were (1) bidirectional endoscopy after diagnosis of IDA and (2) colonoscopy or sigmoidoscopy after diagnosis of hematochezia. The association between diagnostic testing factors and diagnostic test completion was examined using Poisson models. Results: There were 59â¯169 veterans with a diagnosis of IDA (mean [SD] age, 40.7 [7.1] years; 30â¯502 men [51.6%]), 189â¯185 veterans with a diagnosis of hematochezia (mean [SD] age, 39.4 [7.6] years; 163â¯690 men [86.5%]), and 2287 veterans with IDA and hematochezia (mean [SD] age, 41.6 [6.9] years; 1856 men [81.2%]). The cumulative 2-year diagnostic workup completion rate was 22% (95% CI, 22%-22%) among veterans with IDA and 40% (95% CI, 40%-40%) among veterans with hematochezia. Veterans with IDA were mostly aged 40 to 49 years (37â¯719 [63.7%]) and disproportionately Black (24â¯480 [41.4%]). Women with IDA (rate ratio [RR], 0.42; 95% CI, 0.40-0.43) had a lower likelihood of diagnostic test completion compared with men with IDA. Black (RR, 0.65; 95% CI, 0.62-0.68) and Hispanic (RR, 0.88; 95% CI, 0.82-0.94) veterans with IDA were less likely to receive diagnostic testing compared with White veterans with IDA. Veterans with hematochezia were mostly White (105â¯341 [55.7%]). Among veterans with hematochezia, those aged 30 to 49 years were more likely to receive diagnostic testing than adults younger than 30 years of age (age 30-39 years: RR, 1.15; 95% CI, 1.12-1.18; age 40-49 years: RR, 1.36; 95% CI, 1.33-1.40). Hispanic veterans with hematochezia were less likely to receive diagnostic testing compared with White veterans with hematochezia (RR, 0.96; 95% CI, 0.93-0.98). Conclusions and Relevance: In the cohorts of veterans younger than 50 years with IDA and/or hematochezia, the diagnostic test completion rate was low. Follow-up was less likely among female, Black, and Hispanic veterans with IDA and Hispanic veterans with hematochezia. Optimizing timely follow-up across social and demographic groups may contribute to improving colorectal cancer outcomes and mitigate disparities.
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Anemia Ferropriva , Masculino , Feminino , Adulto , Humanos , Anemia Ferropriva/diagnóstico , Anemia Ferropriva/epidemiologia , Estudos de Coortes , Colonoscopia , Endoscopia Gastrointestinal , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiologiaRESUMO
Tea is one of the most popular beverages, it has many health benefits and flavor properties due to the presence of numerous secondary metabolites. Camellia assamica is also a main source of tea, which is mainly planted in the regions of southwest China. In this study, a non-targeted and targeted metabolomics analysis and sensory evaluation on tea leaves with and without mistletoe (Viscum articulatum) was carried out using liquid chromatography-mass spectrometry. RNA-seq-based transcriptomic analysis was conducted in parallel on the same samples, subsequently gene expression and metabolic differentiation were also investigated. Tea leaves with mistletoe presented much lower contents of (-)-catechin, (-)-epicatechin, (-)-gallocatechin gallate and (-)-epicatechin gallate, but significantly higher levels of free amino acids including Arg, Asp, GABA and Gln than that without mistletoe. Transcriptomic analysis also confirmed the main differentially expressed genes (DEGs) containing phenylpropanoid and flavonoid biosynthesis were down-regulated, but genes of amino acid biosynthesis were up-regulated. qRT-PCR analysis further revealed that the relative expression of CsCHS, CsC4H, CsANS, CsLAR, and CsF3H was hindered, while CsglyA and CsilvE expression was increased.
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Cancer surgery remains a mainstay in clinical treatment. However, the efficacy of subsequent therapies largely depends on the precise evaluation of postoperative prognoses, underscoring the critical need for a comprehensive and accurate assessment of surgical outcomes. Nanoprobes targeting tumors offer a promising solution for visual prognostic assessment. In this study, we developed a "Spindle Monitor" system, designated as APPADs (Au NBPs@PDA-pep-AS1411-Dox), composed of core-shell nanoparticles. The core was made up of gold nanobipyramids (Au NBPs), coated with polydopamine (PDA), and subsequently loaded with peptide chains, AS1411, and doxorubicin (Dox). Upon deployment in the acidic tumor microenvironment (TME), APPADs released substantial amounts of Dox, initiating the apoptotic process. This triggered the activity of caspase-3, which is a crucial executor in the apoptotic pathway. Consequently, DEVD, a specific recognition site for caspase-3, was cleaved, enabling the disconnection of FITC-conjugated peptide chains and the recovery of fluorescence. Through assessing this fluorescence imaging effect, local laser irradiation could be precisely guided to the postoperative site, facilitating a synergistic combination of photothermal therapy and chemotherapy. Specifically, our "Spindle Monitor" APPADs had been validated to achieve accurate fluorescence imaging in vitro and in vivo, which demonstrated its potential value as a versatile tool for evaluating postoperative prognosis in surgical treatments, such as thyroid cancer, and assessing chemotherapy efficacy in difficult cases, like late-stage osteosarcoma. This promising tool lays a good foundation for development in visual prognosis evaluation after tumor surgery.
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INTRODUCTION: Achalasia is a postulated risk factor for esophageal cancer (EC); however, EC-associated risk in achalasia is understudied. We aimed to evaluate EC risk among individuals within the nationwide Veterans Affairs Achalasia Cohort (VA-AC). METHODS: We conducted a matched cohort study among US Veterans ≥18 years from 1999-2019. Individuals with achalasia were age- and sex-matched 1:4 to individuals without achalasia. Follow-up continued from study entry until diagnosis with incident/fatal EC (primary outcome), death from non-EC related causes, or end of the study follow up (12/31/2019). Association between achalasia and EC risk was examined using Cox regression models. RESULTS: We included 9,315 individuals in the analytic cohort (median age 55 years; 92% male): 1,863 with achalasia matched to 7,452 without achalasia. During median 5.5 years follow-up, 17 esophageal cancers occurred (3 esophageal adenocarcinoma (EAC), 12 squamous cell carcinoma (SCC), 2 unknown-type) among individuals with achalasia, compared to 15 esophageal cancers (11 EAC, 1 SCC, 3 unknown-type) among those without achalasia. EC incidence for those with achalasia was 1.4 per 1,000 person-years, and median time from achalasia diagnosis to EC development was 3.0 years (Q1-Q3: 1.3-9.1). Individuals with achalasia had higher cumulative EC incidence at 5, 10, and 15-years follow-up compared to individuals without achalasia, and EC risk was 5-fold higher (hazard ratio 4.6, 95% CI 2.3-9.2). DISCUSSION: Based on substantial EC risk, individuals with achalasia may benefit from a high index of suspicion and endoscopic surveillance for EC.
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A porous hydrogen-bonded organic framework (HOF) structure was explored for the first time in the design of high-performance electrochromic devices (ECDs) using polyoxometalate (POM)-based charge-balancing layers as counter electrodes (CEs). The novelty of this work lies in the facile construction of films using small molecule-based EC materials to form a porous HOF structure. A full-cell model of an ECD was constructed by utilizing a POM-based CE to optimize the voltage distribution on the HOF-coated working electrode (WE). The addition of PW12O403- (PW12) on CE significantly enhanced the voltage distribution on EC electrodes and decreased the overvoltage on the WE, further preventing the formation of non-EC species and resulting in a 3.3-fold increase in the lifetime of the ECD. The optical contrast was enhanced from 47% (TiO2 only) to 68%, and the coloration efficiency was enhanced from 185 (TiO2 only) to 373 cm2 C-1. The optimized voltage distribution on the WE, leading to the fast response time and high optical EC contrast, could be explained by the charge-balancing effect. Overall, this new finding provides a robust framework for designing high-performance ECDs, taking advantage of the porous morphology and potential matching of the HOF and PW12.
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AIM: The effect of increased vitamin D levels on vascular function in patients with chronic kidney disease (CKD) is controversial. This meta-analysis aimed to assess the effect of regulated vitamin D increase on vascular markers in patients with CKD. DATA SYNTHESIS: We searched PubMed, Web of Science, Embase and ClinicalTrials.gov from database inception up until July 21, 2023. We included randomized controlled trials assessing the effects of using vitamin D and its analogues on vascular function in patients with CKD. Fixed-effects and random-effects model analyses were performed using weighted mean difference effects for each trial by heterogeneity (I2) assessment. Primary outcomes encompassed blood flow-mediated dilation (FMD)ãpulse wave velocity (PWV) and augmentation index (AIx). FINDINGS: From 1964 records we selected 12 trials, 5 (n = 331) on FMD, 8 (n = 626) on PWV and 4 (n = 393) on AIx. Vitamin D and VDRA supplementation failed to significantly improve FMD (WMD 1.68%; 95% CI -0.18 to 3.53; P = 0.08; I2 = 88%)ãPWV (WMD -0.41 m/s; 95%CI -0.95 to 0.13; P = 0.14; I2 = 57%)and AIx (WMD -0.53%; 95%CI -1.69 to 0.63; P = 0.37; I2 = 0%). Subgroup analysis revealed that 2 µg paricalcitol significantly improved FMD (WMD 2.09%; 95%CI 1.28 to 2.90; P < 0.00001); I2 = 0%), as did cholecalciferol (WMD 5.49%; 95% CI 4.35 to 6.63; P < 0.00001). CONCLUSION: Supplementation vitamin D and VDRA are associated with improved vascular function as measured by FMD, but not arterial stiffness as measured by PWV and AIx, tentatively suggesting that regulating the increase of vitamin D could not potentially reduce the incidence of cardiovascular disease.
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The oocyte, a long-lived, post-mitotic cell, is the locus of reproductive aging in women. Female germ cells replicate only during fetal life and age throughout reproductive life. Mechanisms of oocyte aging include accumulation of oxidative damage, mitochondrial dysfunction and disruption of proteins, including cohesion. Nobel Laureate Bob Edwards also discovered a "production line" during oogonial replication in the mouse, wherein the last oocytes to ovulate in the adult derived from the last oogonia to exit mitotic replication in the fetus. Based on this, we proposed a two hit "telomere theory of reproductive aging" to integrate the myriad features of oocyte aging. The first hit- oocytes remaining in older women traversed more cell cycles during fetal oogenesis. The second hit- oocytes accumulated more environmental and endogenous oxidative damage across the life of the woman. Telomeres could mediate both these aspects of oocyte aging. Telomeres provide a "mitotic clock", with telomere attrition an inevitable consequence of cell division due to of the end-replication problem. And telomere's guanine-rich sequence renders them especially sensitive to oxidative damage, even in post-mitotic cells. Telomerase, the reverse transcriptase that restores telomeres, is better at maintaining than elongating telomeres. Moreover, telomerase remains inactive during much of oogenesis and early development. Oocytes are left with short telomeres, on the brink of viability. In support of this theory, mice with induced telomere attrition and women with naturally occurring telomeropathy suffer diminished ovarian reserve, abnormal embryo development and infertility. In contrast, sperm are produced throughout the life of the male by a telomerase-active progenitor, spermatogonia, resulting in the longest telomeres in the body. In mice, cleavage stage embryos elongate telomeres via "Alternative Lengthening of Telomeres (ALT)", a recombination-based mechanism, rarely encountered outside of telomerase-deficient cancers. Many questions about telomeres and reproduction are raised by these findings:- Does the "normal" telomere attrition observed in human oocytes contribute to their extraordinarily high rate of meiotic non-disjunction? Does recombination-based telomere elongation render embryos susceptible to mitotic non-disjunction (and mosaicism)? Can some features of telomeres serve as markers of oocyte quality?
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OBJECTIVE: Prior research has revealed a heightened prevalence of neoplasms in individuals diagnosed with rheumatoid arthritis (RA). The primary objective of this study is to delve into the causal association between RA and two distinct types of neoplasms: benign neoplasm of bone and articular cartilage (BNBAC) and malignant neoplasm of bone and articular cartilage (MNBAC). METHODS: We employed summary data from genome-wide association analyses (GWAS) to investigate the causal relationship between RA and two neoplasms, BNBAC and MNBAC, using a two-sample bidirectional Mendelian randomization (MR) study design. The IEU OpenGWAS database provided the GWAS summary data for RA, while the Finnish consortium supplied the GWAS summary data for BNBAC and MNBAC. Our analysis involved the utilization of eight distinct MR methods, namely random-effects inverse variance weighted (IVW), MR Egger, weighted median, simple mode, weighted mode, maximum likelihood, penalized weighted median, and fixed effects IVW. Subsequently, we conducted assessments to evaluate heterogeneity, horizontal pleiotropy, outliers, the impact of a single-nucleotide polymorphism (SNP), and adherence to the assumption of normal distribution in the MR analysis. RESULTS: The results from the MR analysis revealed that there was no significant genetic association between RA and BNBAC (P = 0.427, odds ratio [OR] 95% confidence interval [CI] = 0.971 [0.904-1.044]). However, a positive genetic association was observed between RA and MNBAC (P = 0.001, OR 95% CI = 1.413 [1.144-1.745]). Conducting a reverse MR analysis, we found no evidence to support a genetic causality between BNBAC (P = 0.088, OR 95% CI = 1.041 [0.994-1.091]) or MNBAC (P = 0.168, OR 95% CI = 1.013 [0.995-1.031]) and RA. Our MR analysis demonstrated the absence of heterogeneity, horizontal pleiotropy, and outliers and confirmed that the effect was not driven by a single SNP. Additionally, the data exhibited a normal distribution. CONCLUSION: The findings of this study demonstrate that RA constitutes a significant risk factor for MNBAC. In the context of clinical application, it is advisable to conduct MNBAC screening in RA patients and remain vigilant regarding its potential manifestation. Importantly, the outcomes of this investigation introduce a fresh vantage point into the understanding of the tumorigenesis associated with RA.
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Artrite Reumatoide , Cartilagem Articular , Neoplasias , Humanos , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Neoplasias/epidemiologia , Neoplasias/genética , Artrite Reumatoide/epidemiologia , Artrite Reumatoide/genéticaRESUMO
This study aimed to investigate whether brain anatomical structures and functional network connectivity are altered after chronic complete thoracic spinal cord injury (cctSCI) and to determine how these changes impact clinical outcomes. Structural and resting-state functional MRI was performed for 19 cctSCI patients (18 for final statistics) and 19 healthy controls. Voxel-based morphometry (VBM) was used to assess gray matter volume (GMV) with differences between cctSCI patients and controls. VBM results were used as seeds for whole-brain functional connectivity (FC) analysis. The relationship between brain changes and clinical variables was investigated. Compared with those of the control group, the left triangular inferior frontal gyrus, middle frontal gyrus, orbital inferior frontal gyrus, precuneus and parietal superior gyrus volumes of SCI patients decreased, while the left superior frontal gyrus and supplementary motor area volumes increased. Additionally, when the regions with increased GMV were used as seeds, the FC of the parahippocampus and thalamus increased. Subsequent partial correlation analysis showed a positive correlation between FC and total sensorimotor score based on the ASIA criteria (p = 0.001, r = 0.746). Overall, the structural and functional changes in the brain after cctSCI occurred in some visual and cognitive areas and sensory or motor control areas. These findings aid in improving our understanding of the underlying brain injury mechanisms and the subsequent structural and functional reorganization to reveal potential therapeutic targets and track treatment outcomes.
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Molecularly imprinted polymers (MIPs) synthesized from chain functional monomers are restricted by spatial extension and exhibit relatively poor affinity and selectivity; this results in unsatisfactory applications in complex media. In this study, we prepared unique spherical carbonized polymer dots (CPDs-OH) via the incomplete carbonization of 1-allyl-3-vinylimidazolium bromide and ethylene glycol, and used it as a functional monomer to prepare a newly imprinted polymer (CPDs-OH@MIP) in aqueous media. As a result, the CPDs-OH@MIP exhibited effective recognition of oxytetracycline with an impressive imprinting factor of 6.17, surpassing MIPs prepared with chain functional monomers (1-3). Furthermore, CPDs-OH@MIP exhibited excellent adsorption for oxytetracycline (278.52 mg g-1) and achieved equilibrium in 30 min, with stronger resistance to coexisting cations, anions, and humic acid. Compared to other MIPs and adsorbents, the recognition performance of CPDs-OH@MIP improved 2-4 times; this polymer could remove >92.1% of oxytetracycline in real water samples with at least 10 cycle times. CPDs-OH@MIP prepared using the special spherical monomer forms a denser structure with fewer nonimprinted regions and precisely imprinted sites, remarkably improving the affinity and selectivity of MIPs combined via hydrogen bonds and electrostatic and π-π interactions. Our proposed strategy provides an effective basis for breakthroughs in the practical application of MIPs.
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This study employs a Bayesian panel vector autoregressive model to examine the impact of economic uncertainty on public health, using an annual, country-level panel dataset of 103 emerging markets and developing countries spanning the years 1995 through 2019. The results from the full sample suggest that the immediate effects of heightened economic uncertainty on health are marginal, yet it may engender prolonged life expectancy and lowered mortality rates. The analysis unveils considerable heterogeneities among various country classifications. The health-enhancing effects of economic uncertainty are predominantly discernible in emerging markets, low-income and upper-middle-income countries. Additionally, a diminution in suicide rates, attributed to escalated economic uncertainty, is uniquely detected in upper-middle-income countries. Furthermore, economic growth and healthcare expenditure emerge as paramount determinants in bolstering overall population health, particularly in lower-middle-income countries. The detrimental effect of environmental pollution on health is more pronounced in emerging markets and middle-income nations. Excluding high-income countries, it is essential to emphasize the beneficial health outcomes resulting from financial development and globalization, as well as the deleterious effects of environmental pollution. Lastly, several policy implications aligned with the findings are outlined, providing a roadmap for decision-makers in these diverse economies to promote better health outcomes.
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Países em Desenvolvimento , Renda , Humanos , Incerteza , Teorema de Bayes , PobrezaRESUMO
Telomeres and their associated proteins protect the ends of chromosomes to maintain genome stability. Telomeres undergo progressive shortening with each cell division in mammalian somatic cells without telomerase, resulting in genome instability. When telomeres reach a critically short length or are recognized as a damage signal, cells enter a state of senescence, followed by cell cycle arrest, programmed cell death, or immortalization. This review provides an overview of recent advances in the intricate relationship between telomeres and genome instability. Alongside well-established mechanisms such as chromosomal fusion and telomere fusion, we will delve into the perspective on genome stability by examining the role of retrotransposons. Retrotransposons represent an emerging pathway to regulate genome stability through their interactions with telomeres.
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Chiral carbon nanohoops with both high fluorescence quantum yield and large luminescence dissymmetry factor are essential to the development of circularly polarized luminescence (CPL) materials. Herein, the rational design and synthesis of a series of highly fluorescent chiral carbon nanohoops TP-[8-13]CPPs via symmetry breaking with a chiral triptycene motif is reported. Theoretical calculations revealed that breaking the symmetry of nanohoops causes a unique size-dependent localization in the highest occupied molecular orbitals (HOMOs) and the lowest unoccupied molecular obtitals (LUMOs) as the increasing of sizes, which is sharply different from those of [n]cycloparaphenylenes. Photophysical investigations demonstrated that TP-[n]CPPs display size-dependent emissions with high fluorescence quantum yields up to 92.9% for TP-[13]CPP, which is the highest value among the reported chiral conjugated carbon nanohoops. The high fluorescence quantum yields are presumably attributed to both the unique acyclic, and radial conjugations and high radiative transition rates, which are further supported by theoretical investigations. Chiroptical studies revealed that chiral TP-[n]CPPs exhibit bright CPL with CPL brightness up to 100.5 M-1 cm-1 for TP-[11]CPP due to the high fluorescence quantum yield. Importantly, the investigations revealed the intrigued size-dependent properties of TP-[n]CPPs with regards to (chir)optical properties, which follow a nice linear relationship versus 1/n. Such a nice linear relationship is not observed in other reported conjugated nanohoops including CPPs.