224 research outputs found
Divergence of stable isotopes in tap water across China
Stable isotopes in water (e.g., δ2H and δ18O) are important indicators of hydrological and ecological patterns and processes. Tap water can reflect integrated features of regional hydrological processes and human activities. China is a large country with significant meteorological and geographical variations. This report presents the first national-scale survey of Stable Isotopes in Tap Water (SITW) across China. 780 tap water samples have been collected from 95 cities across China from December 2014 to December 2015. (1) Results yielded the Tap Water Line in China is δ2H = 7.72 δ18O + 6.57 (r2 = 0.95). (2) SITW spatial distribution presents typical "continental effect". (3) SITW seasonal variations indicate clearly regional patterns but no trends at the national level. (4) SITW can be correlated in some parts with geographic or meteorological factors. This work presents the first SITW map in China, which sets up a benchmark for further stable isotopes research across China. This is a critical step toward monitoring and investigating water resources in climate-sensitive regions, so the human-hydrological system. These findings could be used in the future to establish water management strategies at a national or regional scale
Development and Validation of a New Method to Diagnose Apical Hypertrophic Cardiomyopathy By Gated Single-Photon Emission Computed Tomography Myocardial Perfusion Imaging
Aim The aim of this study is to develop and validate a new method to diagnose apical hypertrophic cardiomyopathy (AHCM) by the integral quantitative analysis of myocardial perfusion and wall thickening from gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI).
Patients and methods Twenty-two consecutive patients, who showed T wave inversion of at least 3 mm in precordial leads and sinus rhythm in ECG, were enrolled. All the patients underwent cardiac magnetic resonance (CMR), gated rest SPECT MPI and echocardiography. According to CMR diagnostic results, 13 patients were categorized as in the AHCM group and the remaining nine patients were categorized as in the non-AHCM group. Operators who were blinded to the CMR diagnosis independently performed the diagnosis by gated SPECT MPI. The regions of interest inside the apical hotspots on the perfusion polar map were drawn and the mean values of wall thickening in the drawn region of interests were calculated. Using MRI diagnosis as the gold standard, AHCM was diagnosed based on receiver operating characteristic analysis of the mean wall thickening in the apical perfusion hotspot. The area under curve, sensitivity, specificity, and accuracy of our method were 0.97, 100, 89, and 95%, respectively.
Conclusion Our new method has high sensitivity, specificity, and accuracy against CMR diagnosis. It has great promise to become a clinical tool in the diagnosis of AHCM
The DNA Methylome and Transcriptome of Different Brain Regions in Schizophrenia and Bipolar Disorder
Extensive changes in DNA methylation have been observed in schizophrenia (SC) and bipolar disorder (BP), and may contribute to the pathogenesis of these disorders. Here, we performed genome-scale DNA methylation profiling using methylated DNA immunoprecipitation followed by sequencing (MeDIP-seq) on two brain regions (including frontal cortex and anterior cingulate) in 5 SC, 7 BP and 6 normal subjects. Comparing with normal controls, we identified substantial differentially methylated regions (DMRs) in these two brain regions of SC and BP. To our surprise, different brain regions show completely distinct distributions of DMRs across the genomes. In frontal cortex of both SC and BP subjects, we observed widespread hypomethylation as compared to normal controls, preferentially targeting the terminal ends of the chromosomes. In contrast, in anterior cingulate, both SC and BP subjects displayed extensive gain of methylation. Notably, in these two brain regions of SC and BP, only a few DMRs overlapped with promoters, whereas a greater proportion occurs in introns and intergenic regions. Functional enrichment analysis indicated that important psychiatric disorder-related biological processes such as neuron development, differentiation and projection may be altered by epigenetic changes located in the intronic regions. Transcriptome analysis revealed consistent dysfunctional processes with those determined by DMRs. Furthermore, DMRs in the same brain regions from SC and BP could successfully distinguish BP and/or SC from normal controls while differentially expressed genes could not. Overall, our results support a major role for brain-region-dependent aberrant DNA methylation in the pathogenesis of these two disorders
Ancient mitochondrial genomes reveal extensive genetic influence of the steppe pastoralists in Western Xinjiang
The population prehistory of Xinjiang has been a hot topic among geneticists, linguists, and archaeologists. Current ancient DNA studies in Xinjiang exclusively suggest an admixture model for the populations in Xinjiang since the early Bronze Age. However, almost all of these studies focused on the northern and eastern parts of Xinjiang; the prehistoric demographic processes that occurred in western Xinjiang have been seldomly reported. By analyzing complete mitochondrial sequences from the Xiabandi (XBD) cemetery (3,500–3,300 BP), the up-to-date earliest cemetery excavated in western Xinjiang, we show that all the XBD mitochondrial sequences fall within two different West Eurasian mitochondrial DNA (mtDNA) pools, indicating that the migrants into western Xinjiang from west Eurasians were a consequence of the early expansion of the middle and late Bronze Age steppe pastoralists (Steppe_MLBA), admixed with the indigenous populations from Central Asia. Our study provides genetic links for an early existence of the Indo-Iranian language in southwestern Xinjiang and suggests that the existence of Andronovo culture in western Xinjiang involved not only the dispersal of ideas but also population movement.Introduction Materials and methods - Archaeological Background, Sampling, and Sequencing - Sequence Mapping and Mitochondrial DNA Haplogroup Determination - Analysis of Xiabandi Mitochondrial DNA Genomes Results - Mitochondrial DNA Authentication and Contamination Assessment - Major Bronze Age Steppe Pastoralist Origin of the Xiabandi Mitochondrial Haplogroups - Expansion of the Bronze Age Steppe Pastoralists as a Dynamic Process to Form the Genetic Landscape of Xiabandi Individuals Discussion Conclusion
The prognostic value of multiparametric cardiac magnetic resonance in patients with systemic light chain amyloidosis
BackgroundLate gadolinium enhancement (LGE) is a classic imaging modality derived from cardiac magnetic resonance (CMR), which is commonly used to describe cardiac tissue characterization. T1 mapping with extracellular volume (ECV) and native T1 are novel quantitative parameters. The prognostic value of multiparametric CMR in patients with light chain (AL) amyloidosis remains to be thoroughly investigated.MethodsA total of 89 subjects with AL amyloidosis were enrolled from April 2016 to January 2021, and all of them underwent CMR on a 3.0 T scanner. The clinical outcome and therapeutic effect were observed. Cox regression was used to investigate the effect of multiple CMR parameters on outcomes in this population.ResultsLGE extent, native T1 and ECV correlated well with cardiac biomarkers. During a median follow-up of 40 months, 21 patients died. ECV (hazard ratio [HR]: 2.087 for per 10% increase, 95% confidence interval [CI]: 1.379-3.157, P < 0.001) and native T1 (HR: 2.443 for per 100 ms increase, 95% CI: 1.381-4.321, P=0.002) were independently predictive of mortality. A novel prognostic staging system based on median native T1 (1344 ms) and ECV (40%) was similar to Mayo 2004 Stage, and the 5-year estimated overall survival rates in Stage I, II, and III were 95%, 80%, and 53%, respectively. In patients with ECV > 40%, receiving autologous stem cell transplantation had higher cardiac and renal response rates than conventional chemotherapy.ConclusionBoth native T1 and ECV independently predict mortality in patients with AL amyloidosis. Receiving autologous stem cell transplantation is effective and significantly improves the clinical outcomes in patients with ECV > 40%
Evaluation of white matter microstructural alterations in premature infants with necrotizing enterocolitis
Background: Preterm infants with necrotizing enterocolitis (NEC) are at high risk of adverse neurodevelopmental outcomes. The aim of this study was to explore the value of diffusion tensor imaging (DTI) combined with serum C-reactive protein (CRP) and procalcitonin (PCT) in evaluating alterations of white matter (WM) microstructure in preterm infants with NEC.
Methods: A retrospective cross-sectional study was conducted in which all participants were consecutively enrolled at The Third Affiliated Hospital of Zhengzhou University from June 2017 and October 2021. Data from 30 preterm infants with NEC [mean gestational age at birth 31.41±1.15 weeks; mean age at magnetic resonance imaging (MRI) 37.53±3.08 weeks] and 40 healthy preterm infants with no NEC were recorded (mean gestational age at birth 32.27±2.09 weeks; mean age at MRI 37.15±3.23 weeks). WM was used to obtain the fractional anisotropy (FA) and mean diffusivity (MD) values of the regions of interest (ROIs). Additionally, serum levels of CRP and PCT were determined. Spearman correlation analysis was performed between the WM-derived parameters, CRP level, and the PCT serum index.
Results: Preterm infants with NEC had reduced FA values and elevated MD values in WM regions [posterior limbs of the internal capsule (PLIC), lentiform nucleus (LN), frontal white matter (FWM)] compared to the control group (P<0.05). Additionally, the FA of the PLIC was negatively correlated with serum CRP (r=−0.846; P<0.05) and PCT (r=−0.843; P<0.05). Meanwhile, the MD of PLIC was positively correlated with serum CRP (r=0.743; P<0.05) and PCT (r=0.743; P<0.05, respectively). The area under the curve (AUC) of FA and MD combined with CRP and PCT in the diagnosis of WM microstructure alterations with NEC was 0.968, representing a considerable improvement in predicted efficacy over single indicators, including FA [AUC: 0.938; 95% confidence interval (CI): 0.840–0.950], MD (AUC: 0.807; 95% CI: 0.722–0.838), CRP (AUC: 0.867; 95% CI: 0.822–0.889), and PCT (AUC: 0.706; 95% CI: 0.701–0.758).
Conclusions: WM can noninvasively and quantitatively assess the WM microstructure alterations in preterm infants with NEC. WM combined with serum CRP and PCT demonstrated superior performance in detecting and evaluating WM microstructure alterations in preterm infants with NEC
ALMA [N \i\i ] 205 \mu m Imaging Spectroscopy of the Lensed Submillimeter galaxy ID 141 at redshift 4.24
We present the Atacama Large Millimeter/submillimeter Array (ALMA)
observation of the Sub-millimeter galaxy (SMG) ID 141 at z=4.24 in the [N II]
205 m line (hereafter [N II]) and the underlying continuum at (rest-frame)
197.6 m. Benefiting from lensing magnification by a galaxy pair at
z=0.595, ID 141 is one of the brightest z SMGs. At the angular resolutions
of to ( kpc), our observation clearly
separates, and moderately resolves the two lensed images in both continuum and
line emission at . Our continuum-based lensing model implies an
averaged amplification factor of and reveals that the de-lensed
continuum image has the S\'ersic index and the S\'ersic radius of
kpc). Furthermore, the reconstructed [N II] velocity
field in the source plane is dominated by a rotation component with a maximum
velocity of km/s at large radii, indicating a dark matter halo mass
of . This, together with the reconstructed velocity
dispersion field being smooth and modest in value ( km/s) over much of
the outer parts of the galaxy, favours the interpretation of ID 141 being a
disk galaxy dynamically supported by rotation. The observed [N II]/CO (7-6) and
[N II]/[C II] 158 m line luminosity ratios, which are consistent with the
corresponding line ratio vs. far-infrared color correlation from local luminous
infrared galaxies, imply a de-lensed star formation rate of (/yr and provide an independent estimate on the size of
the star-forming region kpc in radius.Comment: 13 pages, 6 figures, 2 tables, accepted by ApJ, lensing model code
can be found here https://gitlab.com/cxylzlx/tiny_len
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