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1.
Evol Appl ; 17(9): e13686, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39247090

RESUMEN

The unprecedented habitat fragmentation or loss has threatened the existence of many species. Therefore, it is essential to understand whether and how these species can pace with the environmental changes. Recent advantages in landscape genomics enabled us to identify molecular signatures of adaptation and predict how populations will respond to changing environments, providing new insights into the conservation of species. Here, we investigated the pattern of neutral and putative adaptive genetic variation and its response to changing environments in a tertiary relict tree species, Taxus cuspidata Sieb. et Zucc, which is distributed in northeast China and adjacent regions. We investigated the pattern of genetic diversity and differentiation using restriction site-associated DNA sequencing (RAD-seq) and seven nuclear microsatellites (nSSRs) datasets. We further explored the endangered mechanism, predicted its vulnerability in the future, and provided guidelines for the conservation and management of this species. RAD-seq identified 16,087 single nucleotide polymorphisms (SNPs) in natural populations. Both the SNPs and nSSRs datasets showed high levels of genetic diversity and low genetic differentiation in T. cuspidata. Outlier detection by F ST outlier analysis and genotype-environment associations (GEAs) revealed 598 outlier SNPs as putative adaptive SNPs. Linear redundancy analysis (RDA) and nonlinear gradient forest (GF) showed that the contribution of climate to genetic variation was greater than that of geography, and precipitation played an important role in putative adaptive genetic variation. Furthermore, the genetic offset and risk of non-adaptedness (RONA) suggested that the species at the northeast edge may be more vulnerable in the future. These results suggest that although the species has maintained high current genetic diversity in the face of recent habitat loss and fragmentation, future climate change is likely to threaten the survival of the species. Temperature (Bio03) and precipitation (Prec05) variables can be potentially used as predictors of response of T. cuspidata under future climate. Together, this study provides a theoretical framework for conservation and management strategies for wildlife species in the context of future climate change.

2.
Phys Rev Lett ; 133(6): 061001, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39178452

RESUMEN

In this Letter we try to search for signals generated by ultraheavy dark matter at the Large High Altitude Air Shower Observatory (LHAASO) data. We look for possible γ rays by dark matter annihilation or decay from 16 dwarf spheroidal galaxies in the field of view of the LHAASO. Dwarf spheroidal galaxies are among the most promising targets for indirect detection of dark matter that have low fluxes of astrophysical γ-ray background while having large amount of dark matter. By analyzing more than 700 days of observational data at LHAASO, no significant dark matter signal from 1 TeV to 1 EeV is detected. Accordingly we derive the most stringent constraints on the ultraheavy dark matter annihilation cross section up to EeV. The constraints on the lifetime of dark matter in decay mode are also derived.

3.
Phys Rev Lett ; 133(7): 071501, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39213544

RESUMEN

On 9 October 2022, the Large High Altitude Air Shower Observatory (LHAASO) reported the observation of the very early TeV afterglow of the brightest-of-all-time gamma-ray burst 221009A, recording the highest photon statistics in the TeV band ever obtained from a gamma-ray burst. We use this unique observation to place stringent constraints on the energy dependence of the speed of light in vacuum, a manifestation of Lorentz invariance violation (LIV) predicted by some quantum gravity (QG) theories. Our results show that the 95% confidence level lower limits on the QG energy scales are E_{QG,1}>10 times the Planck energy E_{Pl} for the linear LIV effect, and E_{QG,2}>6×10^{-8}E_{Pl} for the quadratic LIV effect. Our limits on the quadratic LIV case improve previous best bounds by factors of 5-7.

4.
Phys Rev Lett ; 132(13): 131002, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38613275

RESUMEN

We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15 PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.

5.
Plant Dis ; 2024 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-38616399

RESUMEN

Oaks are the most abundant trees in naturally regenerated forests in China, play a crucial role in preventing soil erosion and maintaining ecological stability (Du et al. 2022). Quercus guyavifolia H. Léveillé (Fagaceae family, Subgenus Cerris, section Ilex), is endemic in China, distributed in the southeastern boundary of the Qinghai-Tibet Plateau, with elevations from 2, 000 - 4, 500 m a.s.l. (Denk et al. 2018; Sun et al. 2016). Powdery mildew is a prevalent disease of oaks with up to 60% of foliage infection, which can induce leaf necrosis or deformation and might contribute to oak decline (Marçais and Desprez-Loustau 2014). In September 2023, we found leaves of Q. guyavifolia near Yunnan Baima Snow Mountain covered with white fungal colonies. Diseased Q. guyavifolia plants were transplanted into a greenhouse at Yunnan University for pathogenicity tests. Conidia from diseased plants were blown into twenty healthy Q. guyavifolia seedlings by cold air blower and five non-inoculated healthy seedlings were used as control. The inoculated seedlings developed powdery mildew symptoms within ten days on both sides of the leaves. Trypan blue staining was used to identify the pathogen that infects Q. guyavifolia (Xiao et al. 2017). Microscopic examination revealed abundant conidia and extensive branched hyphae on leaves, similar to the characteristics of powdery mildew fungi. The mean length and width of conidia were 29.06 ± 3.96 × 9.52 ± 1.36 µm (n = 50). We collected fungi (YNBAIMAXS01) and extracted genomic DNA from five diseased plants (from the same location) using the CTAB method. We amplified and sequenced the ITS (Gardes and Bruns, 1993), MS294, and MS447 (two nuclear protein-encoding genes; Feau et al. 2011; GenBank numbers: PP079015, PP083693, PP083694). BLAST analysis revealed 100% identity of above three sequences with the ITS of Erysiphe quercicola isolate DACA010 (GenBank accession MT569439), MS294 of E. quercicola isolate GEM09_11_FRTB1 (GenBank accession KY348509), and MS447 of E. quercicola isolate A1I1.5 (GenBank accession KY466619). Therefore, the isolate YNBAIMAXS01 was identified as E. quercicola based on its morphological and molecular characteristics. Sequences from the above three regions for YNBAIMAXS01 and five Erysiphe species were used to construct a Maximum likelihood (ML) tree. In addition, we constructed a ML tree using only the ITS region of YNBAIMAXS01 and eight Erysiphe species from GenBank to better distinguish E. quercicola from these species. Both trees were constructed using MEGA X with K2 + G as best model. The ML trees confirmed the powdery mildew fungi isolated from Q. guyavifolia is closely related to E. alphitoides. To date, thirty-four powdery mildew species belonging to genus Erysiphe have been found affecting Quercus and nine oak species can be infected by E. quercicola (https://fungi.ars.usda.gov/). To our knowledge, this is the first report of powdery mildew caused by E. quercicola on Q. guyavifolia, thus the development of control strategies and disease management is urgently needed.

6.
Ecol Evol ; 14(2): e11032, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38357593

RESUMEN

Plant phenotypic characteristics, especially leaf morphology of leaves, are an important indicator for species identification. However, leaf shape can be extraordinarily complex in some species, such as oaks. The great variation in leaf morphology and difficulty of species identification in oaks have attracted the attention of scientists since Charles Darwin. Recent advances in discrimination technology have provided opportunities to understand leaf morphology variation in oaks. Here, we aimed to compare the accuracy and efficiency of species identification in two closely related deciduous oaks by geometric morphometric method (GMM) and deep learning using preliminary identification of simple sequence repeats (nSSRs) as a prior. A total of 538 Asian deciduous oak trees, 16 Q. aliena and 23 Q. dentata populations, were firstly assigned by nSSRs Bayesian clustering analysis to one of the two species or admixture and this grouping served as a priori identification of these trees. Then we analyzed the shapes of 2328 leaves from the 538 trees in terms of 13 characters (landmarks) by GMM. Finally, we trained and classified 2221 leaf-scanned images with Xception architecture using deep learning. The two species can be identified by GMM and deep learning using genetic analysis as a priori. Deep learning is the most cost-efficient method in terms of time-consuming, while GMM can confirm the admixture individuals' leaf shape. These various methods provide high classification accuracy, highlight the application in plant classification research, and are ready to be applied to other morphology analysis.

7.
Nat Commun ; 15(1): 1683, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38395938

RESUMEN

Dipterocarpoideae species form the emergent layer of Asian rainforests. They are the indicator species for Asian rainforest distribution, but they are severely threatened. Here, to understand their adaptation and population decline, we assemble high-quality genomes of seven Dipterocarpoideae species including two autotetraploid species. We estimate the divergence time between Dipterocarpoideae and Malvaceae and within Dipterocarpoideae to be 108.2 (97.8‒118.2) and 88.4 (77.7‒102.9) million years ago, and we identify a whole genome duplication event preceding dipterocarp lineage diversification. We find several genes that showed a signature of selection, likely associated with the adaptation to Asian rainforests. By resequencing of two endangered species, we detect an expansion of effective population size after the last glacial period and a recent sharp decline coinciding with the history of local human activities. Our findings contribute to understanding the diversification and adaptation of dipterocarps and highlight anthropogenic disturbances as a major factor in their endangered status.


Asunto(s)
Dipterocarpaceae , Genómica , Bosque Lluvioso , Genoma , Filogenia
8.
J Dairy Sci ; 107(3): 1620-1629, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37806623

RESUMEN

Supplementation of oral Ca via blanket administration of an oral Ca bolus at 0 and 24 h after calving has shown limited success in increasing production and minimizing adverse health events. Recent evidence that reductions in blood Ca at 4 d in milk (DIM) are more closely associated with negative outcomes than hypocalcemia at 0 to 24 h postpartum might explain this lack of Ca bolus efficacy. Therefore, our primary objective was to explore the effect of delayed oral Ca bolus supplementation on milk production, with secondary objectives of exploring the effects on disease incidence and postpartum blood Ca dynamics. We conducted a randomized controlled trial on multiparous Holstein cows (n = 998) from 4 herds in New York. At calving, cows were randomly assigned to 1 of 3 treatment groups: (1) control, no supplemental Ca at or around parturition (CON; n = 343); (2) conventional bolus, an oral Ca bolus containing 43 g of Ca at calving and 24 h later (BOL-C; n = 330); or (3) delayed bolus, an oral Ca bolus containing 43 g of Ca at 48 and 72 h after calving (BOL-D; n = 325). We created generalized linear mixed models to analyze differences in milk yield for the first 10 wk of lactation and serum total Ca (tCa) at 1 and 4 DIM between treatment groups; multivariable Poisson regression models were used to analyze adverse event outcomes (metritis, displaced abomasum, herd removal, or a combination of one or more of the 3) in the first 30 DIM. Milk yield increased by week and was not affected by treatment. However, a treatment by parity group interaction for milk yield showed that BOL-D cows in the third parity produced more milk than third-parity BOL-C or CON cows (BOL-D = 52.0 kg/d, 95% confidence interval [50.6, 53.4] kg/d, BOL-C = 47.9 [46.3, 49.5] kg/d, CON = 49.8 [48.2, 51.2] kg/d). The incidence of adverse health events was similar between treatments (BOL-D = 3.7%, BOL-C = 3.7%, CON = 3.6%). Serum tCa was lower at 1 than 4 DIM, and we detected no difference in tCa between treatment groups. Our findings suggest that delaying oral Ca bolus supplementation has limited influence on blood Ca concentrations but may be beneficial to cohorts of cows as a targeted prophylactic supplement to support milk production.


Asunto(s)
Líquidos Corporales , Calcio , Animales , Bovinos , Femenino , Embarazo , Calcio de la Dieta , Lactancia , Leche
9.
Phys Rev Lett ; 131(15): 151001, 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37897763

RESUMEN

The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°10 TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60 TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.

10.
Phys Rev Lett ; 131(5): 051201, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37595214

RESUMEN

We report the first detection of a TeV γ-ray flux from the solar disk (6.3σ), based on 6.1 years of data from the High Altitude Water Cherenkov (HAWC) observatory. The 0.5-2.6 TeV spectrum is well fit by a power law, dN/dE=A(E/1 TeV)^{-γ}, with A=(1.6±0.3)×10^{-12} TeV^{-1} cm^{-2} s^{-1} and γ=3.62±0.14. The flux shows a strong indication of anticorrelation with solar activity. These results extend the bright, hard GeV emission from the disk observed with Fermi-LAT, seemingly due to hadronic Galactic cosmic rays showering on nuclei in the solar atmosphere. However, current theoretical models are unable to explain the details of how solar magnetic fields shape these interactions. HAWC's TeV detection thus deepens the mysteries of the solar-disk emission.

11.
Science ; 380(6652): 1390-1396, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37289911

RESUMEN

Some gamma-ray bursts (GRBs) have a tera-electron volt (TeV) afterglow, but the early onset of this has not been observed. We report observations with the Large High Altitude Air Shower Observatory (LHAASO) of the bright GRB 221009A, which serendipitously occurred within the instrument's field of view. More than 64,000 photons >0.2 TeV were detected within the first 3000 seconds. The TeV flux began several minutes after the GRB trigger and then rose to a peak ~10 seconds later. This was followed by a decay phase, which became more rapid ~650 seconds after the peak. We interpret the emission using a model of a relativistic jet with half-opening angle of ~0.8°. This is consistent with the core of a structured jet and could explain the high isotropic energy of this GRB.

12.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(3): 393-400, 2023 Mar 10.
Artículo en Chino | MEDLINE | ID: mdl-36942333

RESUMEN

Objective: To describe the prevalence of alcohol consumption and the burden of hemorrhagic stroke and hypertensive heart disease attributed to alcohol consumption in adults aged ≥20 years in 31 provinces in China from 2005 to 2018. Methods: Data from several national representative surveys was used to estimate provincial alcohol exposure level of adults aged ≥20 years from 2005 to 2018 by using kriging interpolation and locally weighted regression methods. Global disease burden research method and data, and China's death cause surveillance data were used to calculate the population attributable fraction (PAF) of hemorrhagic stroke and hypertensive heart disease and the deaths due to alcohol consumption in men and women aged ≥20 years in 31 provinces in China. China census data of 2010 were used to calculate the attributable standardized mortality rate. Results: In 2005 and 2018, the prevalence of alcohol consumption was 58.7% (95%CI: 57.8%-59.5%) and 58.4% (95%CI: 57.6%-59.3%), respectively, in men and 17.0% (95%CI: 16.6%-17.4%) and 18.7% (95%CI:18.1%-19.3%), respectively, in women. The daily alcohol intake was 24.6 (95%CI: 23.8-25.3) g and 27.7 (95%CI: 26.8-28.7) g, respectively, in men and 6.3 (95%CI: 6.0-6.5) g and 5.3 (95%CI: 5.0-5.6) g, respectively, in women. Alcohol exposure level was higher in the provinces in central and eastern China than in western provinces. The lowest exposure level was found in northwestern provinces. From 2005 to 2018, the PAF of hemorrhagic stroke death due to alcohol consumption increased from 5.5% to 6.8%, the attributable deaths increased from 50 200 to 59 100, while the PAF of hypertensive heart disease death due to alcohol consumption increased from 7.0% to 7.7%, the attributable deaths increased from 15 200 to 29 300. The PAF of hypertensive heart disease and hemorrhagic stroke was higher in men than in women, and in central and eastern provinces than in western provinces. In 2018, the standardized mortality rates of hemorrhagic stroke and hypertensive heart disease attributed to alcohol consumption were 4.58/100 000 and 2.11/100 000, respectively. Conclusions: The prevalence of alcohol consumption in men and daily alcohol intake of drinkers were relatively high in China, especially in eastern provinces. Alcohol exposure level was lower in women than in men. Regional measures should be taken to reduce the alcohol intakes in men and current drinkers in order to reduce the health problems caused by alcohol consumption.


Asunto(s)
Cardiopatías , Accidente Cerebrovascular Hemorrágico , Hipertensión , Adulto , Masculino , Humanos , Femenino , Hipertensión/epidemiología , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/epidemiología , Cardiopatías/epidemiología , China/epidemiología
13.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(3): 415-421, 2023 Mar 10.
Artículo en Chino | MEDLINE | ID: mdl-36942336

RESUMEN

Objective: To estimate the risk for type 2 diabetes mellitus (T2DM) death attributed to insufficient whole grain intake in seven regions of China from 2005 to 2018. Methods: Based on China National Nutrition and Health Surveys and China Adult Chronic Disease and Nutrition Surveillance, ordinary Kriging method and locally weighted regression were used to estimate the level of whole grain intake of Chinese residents from 2005 to 2018. Based on the results of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 and Chronic Diseases Risk Factors Surveillance in China, we calculated the population attributable fraction (PAF), attributable death number and attributable mortality rate of T2DM due to insufficient whole grain intake in people aged ≥20 years in different regions of China, and we used the 2010 Chinese census data to compare the changes in T2DM deaths attributed to insufficient intake of whole grains in seven regions of China. Results: The whole grain intake levels of Chinese people over 20 years old in 2002, 2010 and 2015 were 19.0 g/d, 14.3 g/d and 19.8 g/d, respectively. The estimated overall whole grain intake level was 20.1 g/d in Chinese residents in 2018, and the intake level was 19.4 g/d in men and 20.8 g/d in women. Among the seven regions, the intake level was highest in northern China (47.4 g/d) and lowest in southwestern China (6.0 g/d). In 2018, the PAF was lowest in northern China (12.8%) and highest in southwestern China (19.3%). From 2005 to 2018, the PAF varied in the seven regions, and the PAF in northeastern China fluctuated around 18.5%. Other regions showed downward trends, especially in northern China and northwestern China, decreased by 26.4% and 21.2%, respectively. Over the past 14 years, the number of attributable deaths in the seven regions showed upward trends, with the highest annual average growth rate of 6.7% in southern China and the lowest annual average growth rate of 2.4% in northern China. In 2018, the standardized T2DM mortality rate attributed to insufficient whole grain intake in China was 3.13/100 000, and the attributable mortality was 3.21/100 000 in men and 3.05/100 000 in women. The standardized attributable mortality rate was highest in southwestern China (3.97/100 000) and lowest in northern China (1.78/100 000). From 2005 to 2018, the standardized attributable mortality rate increased by 11.5% in men and decreased by 8.1% in women. The standardized attributable mortality rate in southwestern, southern and central China increased by 23.7%, 21.3% and 4.2%, respectively. The standardized attributable mortality rate in northern, northwestern, eastern and northeastern China decreased by 20.9%, 11.0%, 4.5% and 3.9%, respectively. Conclusion: The whole grain intake level of Chinese residents was low, and the whole grain intake of residents in all seven regions should be increased, especially in the southwest, and men should have more whole grain intake than women to reduce the death risk in patients with T2DM.


Asunto(s)
Diabetes Mellitus Tipo 2 , Granos Enteros , Adulto , Masculino , Humanos , Femenino , Adulto Joven , Diabetes Mellitus Tipo 2/epidemiología , Factores de Riesgo , Enfermedad Crónica , China/epidemiología
14.
Rev Sci Instrum ; 93(8): 083518, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-36050087

RESUMEN

A synthetic electron cyclotron emission (ECE) diagnostic is used to interpret ECE signals from preset plasma equilibrium profiles, including magnetic field, electron density, and electron temperature. According to the simulation results, the electron temperature (Te) profile covering the harmonic overlap region can be obtained by receiving ECE signals at the high field side (HFS) of the HL-2M plasma. The third harmonic ECE at the low field side (LFS) cannot pass through the second harmonic resonance layer at the HFS unless the optical thickness (τ) of the second harmonic becomes gray (τ ≤ 2). In addition, the impact of the relativistic frequency down-shift has been evaluated and corrected. The measurable range of the HFS ECE has been calculated by scanning different parameters (electron density, temperature, and magnetic field). Higher plasma parameters allow a wider radial range of electron temperature measurements. The minimum inner measurable position can reach R = 120 cm (r/a = -0.89) when the product of core temperature (Te0) and density (ne0) is greater than 35 × 1019 keV m-3, which is extended by more than 30 cm inward compared with that of the LFS measurement. The HFS ECE will greatly improve the diagnostic ability of ECE systems on the HL-2M tokamak.

15.
New Phytol ; 236(3): 1212-1224, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35706383

RESUMEN

Ecological character displacement (ECD) refers to a pattern of increased divergence at sites where species ranges overlap caused by competition for resources. Although ECD is believed to be common, there are few in-depth studies that clearly establish its existence, especially in plants. Thus, we have compared leaf traits in allopatric and sympatric populations of two East Asian deciduous oaks: Quercus dentata and Quercus aliena. In contrast to previous studies, we define sympatry and allopatry at a local scale, thereby comparing populations that can or cannot directly interact. Using genetic markers, we found greater genetic divergence between the two oak species growing in mixed stands and inferred that long-term gene flow has predominantly occurred asymmetrically from the cold-tolerant species (Q. dentata) to the warm-demanding later colonizing species (Q. aliena). Analysis of leaf traits revealed greater divergence in mixed than in pure oak stands. This was mostly due to the later colonizing species being characterized by more resource-conservative traits in the presence of the other species. Controlling for relevant environmental differences did not alter these conclusions. These results suggest that asymmetric trait divergence can take place where species coexist, possibly due to the imbalance in demographic history of species resulting in asymmetric inter-specific selection pressures.


Asunto(s)
Quercus , Flujo Génico , Marcadores Genéticos , Fenotipo , Quercus/genética , Simpatría
16.
Front Plant Sci ; 13: 858526, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35665182

RESUMEN

The combination of population and landscape genetics can facilitate the understanding of conservation strategy under the changing climate. Here, we focused on the two most diverse and ecologically important evergreen oaks: Quercus aquifolioides and Quercus spinosa in Qinghai-Tibetan Plateau (QTP), which is considered as world's biodiversity hotspot. We genotyped 1,657 individuals of 106 populations at 15 nuclear microsatellite loci throughout the species distribution range. Spatial patterns of genetic diversity were identified by mapping the allelic richness (AR) and locally common alleles (LCA) according to the circular neighborhood methodology. Migration routes from QTP were detected by historical gene flow estimation. The response pattern of genetic variation to environmental gradient was assessed by the genotype-environment association (GEA) analysis. The overall genetic structure showed a high level of intra-species genetic divergence of a strong west-east pattern. The West-to-East migration route indicated the complex demographic history of two oak species. We found evidence of isolation by the environment in Q. aqu-East and Q. spi-West lineage but not in Q. aqu-West and Q. spi-East lineage. Furthermore, priority for conservation should be given to populations that retain higher spatial genetic diversity or isolated at the edge of the distribution range. Our findings indicate that knowledge of spatial diversity and migration route can provide valuable information for the conservation of existing populations. This study provides an important guide for species conservation for two oak species by the integration of population and landscape genetic methods.

17.
Front Plant Sci ; 13: 911163, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35574114

RESUMEN

[This corrects the article DOI: 10.3389/fpls.2022.822217.].

18.
J Biol Chem ; 298(5): 101899, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35398354

RESUMEN

The spinocerebellar ataxias (SCAs) are a class of incurable diseases characterized by degeneration of the cerebellum that results in movement disorder. Recently, a new heritable form of SCA, spinocerebellar ataxia type 48 (SCA48), was attributed to dominant mutations in STIP1 homology and U box-containing 1 (STUB1); however, little is known about how these mutations cause SCA48. STUB1 encodes for the protein C terminus of Hsc70 interacting protein (CHIP), an E3 ubiquitin ligase. CHIP is known to regulate proteostasis by recruiting chaperones via a N-terminal tetratricopeptide repeat domain and recruiting E2 ubiquitin-conjugating enzymes via a C-terminal U-box domain. These interactions allow CHIP to mediate the ubiquitination of chaperone-bound, misfolded proteins to promote their degradation via the proteasome. Here we have identified a novel, de novo mutation in STUB1 in a patient with SCA48 encoding for an A52G point mutation in the tetratricopeptide repeat domain of CHIP. Utilizing an array of biophysical, biochemical, and cellular assays, we demonstrate that the CHIPA52G point mutant retains E3-ligase activity but has decreased affinity for chaperones. We further show that this mutant decreases cellular fitness in response to certain cellular stressors and induces neurodegeneration in a transgenic Caenorhabditis elegans model of SCA48. Together, our data identify the A52G mutant as a cause of SCA48 and provide molecular insight into how mutations in STUB1 cause SCA48.


Asunto(s)
Ataxias Espinocerebelosas , Ubiquitina-Proteína Ligasas , Ubiquitina , Humanos , Mutación , Ataxias Espinocerebelosas/genética , Ataxias Espinocerebelosas/metabolismo , Ubiquitina/genética , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación
19.
J Paediatr Child Health ; 58(7): 1244-1250, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35388934

RESUMEN

AIM: Paediatric eosinophilic gastritis (EG) is a rare disorder and existing literature on diagnostic criteria and management remains lacking. We aim to describe the clinical spectrum and assess the efficacy of dietary elimination and proton-pump inhibitor (PPI) therapy, with particular emphasis on histologic remission in children with primary EG. METHODS: We performed a retrospective study of patients aged 0-18 years diagnosed with EG at a single centre in Singapore from 2013 to 2021. EG was diagnosed based on histological criteria of infiltration of >30 eosinophils per high-power film (HPF) in >5 separate HPFs from gastric biopsies, in the absence of other causes. First-line treatment consisted of PPI therapy and empiric 1-6 food elimination diet (FED). Outcomes measured were clinical, endoscopic and histological remission (defined as eosinophil count <20/HPF in gastric biopsies). RESULTS: Twenty-one (66.7% females) patients were included with median age at diagnosis of 15 months (range:3-192). Majority presented with vomiting (76.2%) and gastrointestinal bleeding (71.4%). Twenty patients were initiated on FED+PPI and 16 had post-treatment biopsies. Clinical, endoscopic and histologic remissions were achieved in 94.7%, 81.3% and 68.8% respectively following FED+PPI. Histologic remission was significantly associated with younger age (9 vs. 132 months; P = 0.026). Four patients who did not respond to FED+PPI were started on oral viscous budesonide, of whom one achieved histological remission and two had clinical improvement. CONCLUSIONS: FED+PPI is effective as first-line treatment in achieving histological remission in paediatric EG particularly in younger patients. Topical corticosteroids can be considered for those who have failed FED+PPI therapy.


Asunto(s)
Enteritis , Esofagitis Eosinofílica , Budesonida , Niño , Enteritis/tratamiento farmacológico , Eosinofilia , Esofagitis Eosinofílica/diagnóstico , Esofagitis Eosinofílica/tratamiento farmacológico , Esofagitis Eosinofílica/patología , Femenino , Gastritis , Humanos , Masculino , Inhibidores de la Bomba de Protones/uso terapéutico , Estudios Retrospectivos
20.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(3): 340-345, 2022 Mar 06.
Artículo en Chino | MEDLINE | ID: mdl-35381656

RESUMEN

Objective: To explore the knowledge, attitude and behavior of salt reduction in adults of Beijing in 2017. Methods: Based on the monitoring data of chronic diseases and corresponding risk factors in adults of Beijing in 2017, the indicators of salt reduction knowledge, attitude and behavior of 13 240 participants aged 18-79 years old were analyzed. The awareness rate, attitude support rate and behavior rate were calculated by complex weighting method, and compared among different age groups, genders, residential areas, and history of hypertension. The proportion of people taking various salt reduction measures to the total number of people was compared. Results: The awareness rate of recommended daily salt intake, the awareness of hypertension caused or aggravated by more salt intake, the attitude support rate and behavior rate of adults were 31.77%, 88.56%, 90.27% and 53.86%, respectively. After weighted adjustment, the awareness rate of recommended daily salt intake was 31.08%, which increased with age (χ2trend=431.56, P<0.001) and education level (χ2trend=95.44, P<0.001). The awareness rate of women was higher than that of men (χ²=118.89, P<0.001), and the awareness rate of population in urban areas was higher than that of population in suburban areas (χ²=34.09, P=0.001). The awareness rate of hypertension caused or aggravated by eating more salt was 86.73%. The support rate of salt reduction attitude was 90.45%. The rate of salt-reducing behavior was 54.05%. Among different salt reduction measures, reducing salt when cooking was the most common measure (52.41%), while the least common one (35.22%) was using low sodium salt. Logistic regression model analysis showed that the gender, age, education level, self-reported history of hypertension, awareness of salt recommendation, awareness of hypertension caused or aggravated by eating more salt, and salt reduction attitude were significantly associated with salt reduction behavior. Conclusion: In 2017, adults in Beijing have a basic understanding of the impact of high-salt diet on health and support salt reduction, but the rate of salt reduction behavior is still relatively low. There are obvious gender and age differences, and the salt reduction measure is simple. Targeted measures should be taken to promote the formation of salt reduction behavior.


Asunto(s)
Hipertensión , Cloruro de Sodio Dietético , Adolescente , Adulto , Anciano , Beijing , Dieta Hiposódica , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Hipertensión/inducido químicamente , Hipertensión/epidemiología , Hipertensión/prevención & control , Masculino , Persona de Mediana Edad , Ingesta Diaria Recomendada , Adulto Joven
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