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We theoretically propose a scheme of the nonreciprocal conversion device between photons of two arbitrary frequencies in a hybrid cavity optomechanical system, where two optical cavities and two microwave cavities are coupled to two different mechanical resonators via radiation pressure. Two mechanical resonators are coupled together via the Coulomb interaction. We study the nonreciprocal conversions between both the same and different types of frequency photons. The device is based on multichannel quantum interference to break the time-reversal symmetry. Our results show the perfect nonreciprocity conditions. By adjusting the Coulomb interaction and the phase differences, we find that the nonreciprocity can be modulated and even transformed into reciprocity. These results provide new insight into the design of nonreciprocal devices, including isolators, circulators, and routers in quantum information processing and quantum networks.
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PREMISE: The phylogeography of coastal plant species is shaped by contemporary and historical biogeographic processes. In this study, we aim to decipher the phylogeography of Derris trifoliata, a woody legume of relatively recent origin and wide distribution, in coastal areas in the Indo-West Pacific (IWP) region. METHODS: Genetic diversity and population structure were assessed by analyzing six nuclear and three chloroplast DNA sequences from 30 populations across the species' range. Phylogeography was inferred by estimating gene flow, divergence time, historical population size changes, and historical habitat suitability using paleoclimatic niche modeling. RESULTS: High genetic diversity was observed at the species level. The populations of three oceanic regions included in this study (i.e., Indian Ocean, South China Sea, and Pacific Ocean) formed distinct clades and likely diverged during the late Pleistocene. Potential barriers to gene flow were identified, including the Sunda and Sahul shelves, geographic distance, and current patterns of oceanic circulation. Analysis of changes in population size supported the bottleneck model, which was strengthened by estimates of habitat suitability across paleoclimatic conditions. CONCLUSIONS: The once widespread distribution of D. trifoliata was fragmented by changes in climatic suitability and biogeographic barriers that arose following sea-level changes during the Pleistocene. In addition, contemporary patterns of oceanic circulation and geographic distance between populations appear to maintain genetic differentiation across its distribution in the IWP.
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Derris , Fabaceae , ADN Mitocondrial/genética , Derris/genética , Fabaceae/genética , Variación Genética , Océano Pacífico , Filogenia , FilogeografíaRESUMEN
BACKGROUND: Until now, the influential factors associated with pleural adenosine deaminase (ADA) activity among children remain unclear. This retrospective study was therefore conducted aiming to investigate the factors associated with negative pleural ADA results in the diagnosis of childhood pleural tuberculosis (TB). METHODS: Between January 2006 and December 2019, children patients with definite or possible pleural TB were recruited for potential analysis. Then, patients were stratified into two categories: negative pleural ADA results group (experimental group, ≤40 U/L) and positive pleural ADA results group (control group, > 40 U/L). Univariate and multivariate logistic regression analyses were performed to estimate risk factors for negative pleural ADA results. RESULTS: A total of 84 patients with pleural TB were recruited and subsequently classified as experimental (n = 17) and control groups (n = 67). Multivariate analysis (Hosmer-Lemeshow goodness-of-fit test: χ2 = 1.881, df = 6, P = 0.930) revealed that variables, such as chest pain (age-adjusted OR = 0.0510, 95% CI: 0.004, 0.583), pleural total protein (≤45.3 g/L, age-adjusted OR = 27.7, 95% CI: 2.5, 307.7), pleural lactate dehydrogenase (LDH, ≤505 U/L, age-adjusted OR = 59.9, 95% CI: 4.2, 857.2) and blood urea nitrogen (≤3.2 mmol/L, age-adjusted OR = 32.0, 95% CI: 2.4, 426.9), were associated with negative pleural ADA results when diagnosing childhood pleural TB. CONCLUSION: Our findings demonstrated that chest pain, pleural total protein, pleural LDH, and blood urea nitrogen were associated with a negative pleural ADA result for the diagnosis of pleural TB among children. When interpreting pleural ADA levels in children with these characteristics, a careful clinical assessment is required for the pleural TB diagnosis.
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Adenosina Desaminasa/análisis , Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis Pleural/diagnóstico , Adolescente , Nitrógeno de la Urea Sanguínea , Estudios de Casos y Controles , Dolor en el Pecho , Niño , Femenino , Humanos , L-Lactato Deshidrogenasa/análisis , Modelos Logísticos , Masculino , Análisis Multivariante , Derrame Pleural/microbiología , Estudios Retrospectivos , Factores de Riesgo , Esputo/microbiología , Tuberculosis Pleural/microbiología , Tuberculosis Pleural/patologíaRESUMEN
Chronic cadmium (Cd) toxicity is a significant health concern, and the mechanism of long-term low-dose Cd exposure on bone has not been fully elucidated yet. This study aimed to assess the association between long-term environmental Cd exposure and bone remodeling in women who aged over 50. A total of 278 non-smoking subjects from Cd-polluted group (n = 191) and non-Cd polluted group (n = 87) were investigated. Bone mineral density (BMD), the levels of three bone turnover markers (BTMs), including total procollagen type 1 amino-terminal propeptide (P1NP), collagen type 1 cross-linked C-telopeptide (ß-CTX), bone-specific alkaline phosphatase (BALP), together with serum soluble receptor activator of nuclear factor-κB ligand (sRANKL) and osteoprotegerin (OPG) were determined. Early markers of renal dysfunction were measured as well. Urinary Cd concentrations ranged from 0.41 to 87.31 µg/g creatinine, with a median of 4.91 µg/g creatinine. Age, BMD, T-score, and prevalence of osteoporosis showed no statistical differences among the quartiles of urinary Cd concentrations, while serum levels of P1NP, ß-CTX, and OPG were higher in the upper quartiles. Multivariate linear regression models indicated significantly positive associations of urinary Cd concentration with serum levels of P1NP, ß-CTX, BALP, sRANKL, and OPG. A ridge regression analysis with T-score and the three BTMs, sRANKL, and OPG, adjusted for age and body mass index (BMI), indicated that except for age and Cd exposure, ß-CTX was a predictor of T-score. These findings demonstrated that Cd may directly accelerate bone remodeling. Serum ß-CTX might be an appropriate biochemical marker for evaluating and monitoring Cd-related bone loss. Capsule: Cadmium (Cd) may directly accelerate bone remodeling and serum ß-CTX is a valuable biochemical marker for evaluating Cd-related bone loss.
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Remodelación Ósea , Cadmio/sangre , Exposición a Riesgos Ambientales/estadística & datos numéricos , Contaminantes Ambientales/sangre , Adulto , Anciano , Fosfatasa Alcalina , Biomarcadores/sangre , Índice de Masa Corporal , Densidad Ósea , Huesos , Colágeno Tipo I , Femenino , Humanos , Persona de Mediana Edad , Osteoporosis/sangre , Osteoprotegerina , Péptidos , Ligando RANK/sangreRESUMEN
As the largest cultivated fiber crop in the world, cotton (Gossypium hirsutum) is often exposed to various biotic stresses during its growth periods. Verticillium wilt caused by Verticillium dahliae is a severe disease in cotton, and the molecular mechanism of cotton resistance for Verticillium wilt needs to be further investigated. Here, we revealed that the cotton genome contains nine types of GST genes. An evolutionary analysis showed that a newly identified cluster (including Gh_A09G1508, Gh_A09G1509 and Gh_A09G1510) located on chromosome 09 of the A-subgenome was under positive selection pressure during the formation of an allotetraploid. Transcriptome analysis showed that this cluster participates in Verticillium wilt resistance. Because the Gh_A09G1509 gene showed the greatest differential expression in the resistant cultivar under V. dahliae stress, we overexpressed this gene in tobacco and found that its overexpression resulted in enhanced Verticillium wilt resistance. Suppression of the gene cluster via virus-induced gene silencing made cotton plants of the resistant cultivar Nongda601 significantly susceptible. These results demonstrated that the GST cluster played an important role in Verticillium wilt resistance. Further investigation showed that the encoded enzymes of the cluster were essential for the delicate equilibrium between the production and scavenging of H2 O2 during V. dahliae stress.
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Resistencia a la Enfermedad/genética , Glutatión Transferasa/genética , Gossypium/genética , Familia de Multigenes/genética , Enfermedades de las Plantas/microbiología , Verticillium/patogenicidad , Arabidopsis/genética , Cacao/genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Genoma de Planta/genética , Glutatión Transferasa/clasificación , Peróxido de Hidrógeno/metabolismo , Vitis/genéticaRESUMEN
BACKGROUND: Expansins (EXPs), a group of proteins that loosen plant cell walls and cellulosic materials, are involved in regulating cell growth and diverse developmental processes in plants. However, the biological functions of this gene family in cotton are still unknown. RESULTS: In this paper, we identified a total of 93 expansin genes in Gossypium hirsutum. These genes were classified into four subfamilies, including 67 GhEXPAs, 8 GhEXPBs, 6 GhEXLAs, and 12 GhEXLBs, and divided into 15 subgroups. The 93 expansin genes are distributed over 24 chromosomes, excluding Ghir_A02 and Ghir_D06. All GhEXP genes contain multiple exons, and each GhEXP protein has multiple conserved motifs. Transcript profiling and qPCR analysis revealed that the expansin genes have distinct expression patterns among different stages of cotton fibre development. Among them, 3 genes (GhEXPA4o, GhEXPA1A, and GhEXPA8h) were highly expressed in the initiation stage, 9 genes (GhEXPA4a, GhEXPA13a, GhEXPA4f, GhEXPA4q, GhEXPA8f, GhEXPA2, GhEXPA8g, GhEXPA8a, and GhEXPA4n) had high expression during the fast elongation stage, and GhEXLA1c and GhEXLA1f were preferentially expressed in the transition stage of fibre development. CONCLUSIONS: Our results provide a solid basis for further elucidation of the biological functions of expansin genes in relation to cotton fibre development and valuable genetic resources for future crop improvement.
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Pared Celular/metabolismo , Regulación de la Expresión Génica de las Plantas , Genoma de Planta , Gossypium/crecimiento & desarrollo , Gossypium/genética , Proteínas de Plantas/genética , Pared Celular/genética , Genes de Plantas , Gossypium/metabolismo , Familia de Multigenes , Proteínas de Plantas/metabolismoRESUMEN
BACKGROUND AND AIMS: Mikania micrantha, a climbing perennial weed of the family Asteraceae, is native to Latin America and is highly invasive in the tropical belt of Asia, Oceania and Australia. This study was framed to investigate the population structure of M. micrantha at a large spatial scale in Asia and to identify how introduction history, evolutionary forces and landscape features influenced the genetic pattern of the species in this region. METHODS: We assessed the genetic diversity and structure of 1052 individuals from 46 populations for 12 microsatellite loci. The spatial pattern of genetic variation was investigated by estimating the relationship between genetic distance and geographical, climatic and landscape resistances hypothesized to influence gene flow between populations. KEY RESULTS: We found high genetic diversity of M. micrantha in this region, as compared with the genetic diversity parameters of other invasive species. Spatial and non-spatial clustering algorithms identified the presence of multiple genetic clusters and admixture between populations. Most of the populations showed heterozygote deficiency, primarily due to inbreeding, and the founder populations showed evidence of a genetic bottleneck. Persistent gene flow throughout the invasive range caused low genetic differentiation among populations and provided beneficial genetic variation to the marginal populations in a heterogeneous environment. Environmental suitability was found to buffer the detrimental effects of inbreeding at the leading edge of range expansion. Both linear and non-linear regression models demonstrated a weak relationship between genetic distance and geographical distance, as well as bioclimatic variables and environmental resistance surfaces. CONCLUSIONS: These findings provide evidence that extensive gene flow and admixture between populations have influenced the current genetic pattern of M. micrantha in this region. High gene flow across the invaded landscape may facilitate adaptation, establishment and long-term persistence of the population, thereby indicating the range expansion ability of the species.
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Mikania/genética , Asia , Australia , Flujo Génico , Variación Genética , Genética de Población , Humanos , Especies Introducidas , Repeticiones de MicrosatéliteRESUMEN
Even though a growing number of reports indicated favorable health effects with fish consumption, kinds of hazardous substances in fish were detected in fish and to be exceeded advisory limitation. Benefit-risk assessment of commonly consumed fish is urgently needed. We conducted fish consumption survey and fish sampling in the coast of South China Sea to assess benefit-risk effect of commonly consumed fish species. For local residents, weekly methyl mercury (MeHg) exposures from commonly consumed fish species ranged from 0.12 to 2.11 µg/kg bw. Apart from Muraenesox cinereus and Acanthopagrus latus, the rest of 92% (23/25) fish species were at low risk of MeHg exposure. Daily docosahexaenoic acid intakes via consuming specific fish were between 42.18 and 1687.04 mg/day. A total of 72% (18/25) fish species could provide 200 mg/day of DNA for local residents. Benefit-risk assessment assuming intelligence quotient (IQ) score model showed net IQ point gains between 1.53 and 5.65 points with consuming various fish species, indicative of large distinction of health benefit from various fish species. This study suggests commonly consumed fish species from China South Sea could bring much more positive effect than negative effect. Species-specific fish should be considered when providing recommendations of fish consumption. Muraenesox cinereus and Acanthopagrus latus should be minded with risk of MeHg exposure in taking large amounts.
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Exposición Dietética/análisis , Ácidos Docosahexaenoicos/análisis , Peces , Compuestos de Metilmercurio/análisis , Alimentos Marinos/análisis , Animales , China , Peces/metabolismo , Humanos , Medición de Riesgo , Especificidad de la EspecieRESUMEN
The first catalytic asymmetric synthesis of highly functionalized pentafluorosulfanylated pyrrolidines is described. The method, based on a 1,3-dipolar cycloaddition reaction of aryl and heteroaryl-substituted glycine Schiff bases with pentafluorosulfanyl acrylic esters, gave access to a broad range of pyrrolidines bearing aryl, naphtyl, and heteroaryl groups. By using Xing-Phos as a catalyst, the corresponding products were obtained in good yields, good to high regioselectivity, and excellent diastereo- and enantioselectivities (up to 98 %â ee). This methodology allowed the preparation of enantioenriched SF5 compounds for the first time using an enantioselective approach.
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Hidrocarburos Fluorados/síntesis química , Pirrolidinas/síntesis química , Compuestos de Azufre/síntesis química , Catálisis , Reacción de Cicloadición , Hidrocarburos Fluorados/química , Estructura Molecular , Pirrolidinas/química , Estereoisomerismo , Compuestos de Azufre/químicaRESUMEN
OBJECTIVE: The objective of this study was to explore whether diffusion kurtosis imaging (DKI) combined with DWI can improve the performance of DWI in detection and assessment of aggressiveness of prostate cancer (PCa). MATERIALS AND METHODS: One hundred twenty patients with complete DK and MR images and diagnosis confirmed by prostate biopsy, including 67 patients with PCa and 53 patients with benign prostatic hyperplasia (BPH), were retrospectively analyzed. The patients with PCa were divided into a low-grade PCa group (Gleason score [GS] ≤ 3 + 3) and intermediate- and high-grade PCa group (GS ≥ 3 + 4). A DKI-derived parameter (i.e., apparent kurtosis coefficient [Kapp]) and a DWI-derived parameter (i.e., apparent diffusion coefficient [ADC]) were fitted. The intraclass correlation coefficient (ICC) test, t test, ROC curves, Delong test, and Spearman correlation were performed. RESULTS: Ninety ROIs in 67 patients with PCa were drawn, including ROIs in 37 low-grade tumors and ROIs in 53 intermediate- and high-grade tumors. PCa and intermediate- and high-grade PCa had significantly lower ADC values and significantly higher Kapp values than BPH and low-grade PCa (p < 0.01 for all). The AUCs of Kapp were significantly lower than the AUCs of ADC in the diagnosis (0.947 vs 0.978, p < 0.001) and grading (0.689 vs 0.894, p = 0.008) of PCa. The AUCs of the combination of the two metrics were significantly higher than the AUCs of Kapp for the diagnosis (0.979 vs 0.947, p = 0.013) and grading (0.934 vs 0.689, p < 0.001) of PCa and were higher than the AUCs of ADC without significance between groups (both p > 0.05). The combination of the two metrics significantly increased the specificity in grading of PCa compared with Kapp alone (0.838 vs 0.730, p = 0.035). CONCLUSION: Both ADC and Kapp can be used as quantitative parameters in detection and assessment of aggressiveness of PCa. The combination of DKI and DWI showed no significant superiority to DWI alone in detection and assessment of the aggressiveness of PCa.
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Imagen de Difusión por Resonancia Magnética/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Anciano , Anciano de 80 o más Años , Biopsia , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estudios RetrospectivosRESUMEN
The offshore area of the South China Sea is an important fishing ground in China. We used a food frequency questionnaire to determine marine fish consumption by local residents, and we detected mercury concentrations in commonly consumed marine fish species. In total, 127.9 g/day of the marine fish consumed was identified in 178 local residents. THg and MeHg concentrations in 209 samples of 22 fish species ranged from 11.3 to 215.0 µg/kg wt and 2.0 to 160.0 µg/kg wt, respectively. The mean MeHg exposure from marine fish to local residents was 0.099 µg/kg bw, accounting for 43.0% of the provisional tolerated weekly intake (PTWI) (1.6 µg/kg bw/week), suggesting a low health risk. However, a potentially high health risk (202.2% of PTWI) was identified in those with 97.5% MeHg exposure.
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Peces , Contaminación de Alimentos/análisis , Mercurio/análisis , Compuestos de Metilmercurio/análisis , Contaminantes Químicos del Agua/análisis , Adolescente , Adulto , Anciano , Animales , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Medición de Riesgo , Adulto JovenRESUMEN
A novel organocatalytic olefinic carbon-sulfur bond forming reaction was developed. Under the catalysis of 10 mol% stable N-heterocyclic carbene, thiols undergo direct nucleophilic substitution reaction with gem-difluoroalkenes to produce α-fluorovinyl thioethers in high yields with excellent Z-selectivity. In this process, bases are not necessary.
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MAIN CONCLUSION: Cotton S-adenosylmethionine decarboxylase-, rather than spermine synthase-, mediated spermine biosynthesis is required for salicylic acid- and leucine-correlated signaling in the defense response to Verticillium dahliae. Spermine (Spm) signaling is correlated with plant resistance to the fungal pathogen Verticillium dahliae. We identified genes for key rate-limiting enzymes in the biosynthesis of Spm, namely S-adenosylmethionine decarboxylase (GhSAMDC) and Spm synthase (GhSPMS). These were found by screening suppression subtractive hybridization and cDNA libraries of cotton (Gossypium) species tolerant to Verticillium wilt. Both were induced early and strongly by inoculation with V. dahliae and application of plant hormones. Silencing of GhSPMS or GhSAMDC in cotton leaves led to a significant accumulation of upstream substrates and, ultimately, enhanced plant susceptibility to Verticillium infection. Exogenous supplementation of Spm to the silenced cotton plants improved resistance. When compared with the wild type (WT), constitutive expression of GhSAMDC in Arabidopsis thaliana was associated with greater Verticillium wilt resistance and higher accumulations of Spm, salicylic acid, and leucine during the infection period. By contrast, transgenic Arabidopsis plants that over-expressed GhSPMS were unexpectedly more susceptible than the WT to V. dahliae and they also had impaired levels of putrescine (Put) and salicylic acid (SA). The susceptibility exhibited in GhSPMS-overexpressing Arabidopsis plants was partially reversed by the exogenous supply of Put or SA. In addition, the responsiveness of those two transgenic Arabidopsis lines to V. dahliae was associated with an alteration in transcripts of genes involved in plant resistance to epidermal penetrations and amino acid signaling. Together, these results suggest that GhSAMDC-, rather than GhSPMS-, mediated spermine biosynthesis contributes to plant resistance against V. dahliae through SA- and leucine-correlated signaling.
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Adenosilmetionina Descarboxilasa/metabolismo , Gossypium/metabolismo , Gossypium/microbiología , Espermina/biosíntesis , Verticillium/patogenicidad , Adenosilmetionina Descarboxilasa/genética , Arabidopsis/genética , Arabidopsis/microbiología , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Leucina/metabolismo , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Putrescina/metabolismo , Ácido Salicílico/metabolismo , Espermina/metabolismo , Espermina Sintasa/genética , Espermina Sintasa/metabolismoRESUMEN
An efficient N-heterocyclic carbene (NHC)-catalyzed vinylogous Michael addition of deconjugated butenolides was developed. In the presence of 5 mol % of the NHC catalyst, both γ-alkyl- and aryl-substituted deconjugated butenolides undergo vinylogous Michael addition with various α, ß-unsaturated ketones, esters, or nitriles to afford γ,γ-disubstituted butenolides containing adjacent quaternary and tertiary carbon centers in good to excellent yields with excellent diastereoselectivities. In this process, the free carbene is assumed to act as a strong Brønsted base to promote the conjugate addition.
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A novel DCC reaction between aromatic aldehydes or ketones and H-phosphonates has been developed for the synthesis of p-formyl or p-acylphenylphosphonates. The synthetic method has excellent para regioselectivities, good yields, and broad substrate scopes and is more benign to the environment. The DCC reaction also tolerates many functional groups, and results in a series of new p-formyl and p-acylphenylphosphonates, which should be important building blocks for the synthesis of versatile arylphosphonate derivatives.
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Aldehídos/química , Hidrocarburos Aromáticos/química , Cetonas/química , Organofosfonatos/química , Acilación , Aldehídos/síntesis química , Formiatos/síntesis química , Formiatos/química , Hidrocarburos Aromáticos/síntesis química , Cetonas/síntesis química , Organofosfonatos/síntesis química , EstereoisomerismoRESUMEN
OBJECTIVE: To perform a prospective study the effects of autologous peripheral blood stem cell (APBSC) transplantation on acoustic radiation force impulse (ARFI) in patients with hepatitis B virus (HBV)-related decompensated cirrhosis. METHODS: A total of 68 hospitalized patients with HBV-related decompensated cirrhosis undergoing conventional treatment were included in the study. Thirty-three of these patients also received APBSC transplantation therapy (treatment group) and 35 did not (control group). The treatment group was observed for postoperative adverse reaction, and changes (pre-vs.post-treatment) in total bilirubin, prothrombin time (PT), albumin (Alb), spleen size and ARFI imaging findings. Statistical analyses were carried out using the t-test, non-parametric test, and chi-square test. RESULTS: The patients who received APBSC transplantation showed improving levels of Alb and PT, but not of total bilirubin, at postoperative weeks 24, 36 and 48, and reduced spleen length and ARFI findings at postoperative weeks 36 and 48.Compared to the baseline data (week 0) for the treatment group and to the data for the control groups, these differences were statistically significant (P less than 0.05). CONCLUSIONS: APBSC transplantation can reduce ARFI imaging findings and improve the pathology of liver fibrosis in patients with HBV-related decompensated cirrhosis.
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Hepatitis B/terapia , Cirrosis Hepática/terapia , Trasplante de Células Madre de Sangre Periférica , Bilirrubina/sangre , Biomarcadores/sangre , Diagnóstico por Imagen de Elasticidad , Virus de la Hepatitis B , Humanos , Cirrosis Hepática/virología , Estudios Prospectivos , Tiempo de ProtrombinaRESUMEN
A dehydrogenative cross-coupling reaction between allylic C-H bonds and the α-C-H bond of ketones or aldehydes was developed using Cu(OTf)2 as a catalyst and DDQ as an oxidant. This synthetic approach to γ,δ-unsaturated ketones and aldehydes has the advantages of broad scope for both ketones and aldehydes as reactants, mild reaction conditions, good yields and atom economy. A plausible mechanism using Cu(OTf)2 as a Lewis acid catalyst was also proposed (DDQ=2,3-dichloro-5,6-dicyano-1,4-benzoquinone; Tf=trifluoromethanesulfonate).
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Based on the PM2.5 monitoring data, NCEP data, and the meteorological data of the weather situation analysis at the corresponding time in Yangquan City from 2020 to 2022, using the HYSPLIT4 backward trajectory model, multi-station potential source contribution factor analysis ï¼MS-PSCFï¼ and trajectory density analysis ï¼TDAï¼ were introduced to study the differentiation and classification of PM2.5 transport channels and potential sources in Yangquan City. The results showed thatï¼ â The PM2.5 pollution in Yangquan was mainly concentrated in Yangquan and Pingding, whereas the pollution in Yuxian was relatively light. The proportion of days with different pollution levels and the average and maximum values of PM2.5 concentration in Yangquan and Pingding were significantly higher than those in Yuxian, and the distribution characteristics of PM2.5 were closely related to the local special terrain. â¡ The amount of PM2.5 pollution and the concentration of PM2.5 in different pollution levels were the highest in light wind weather. The influence of east-west regional transport on PM2.5 pollution times and PM2.5 concentration of Yangquan and Pingding was obvious, and the contribution of east wind was significant. The influence of local pollution sources was the main factor in the moderate pollution weather in Yuxian County. ⢠There were four main ground conditions for the generation and maintenance of moderate or above pollution weatherï¼ warm low pressure type ï¼22%ï¼, high pressure front ï¼bottomï¼ type ï¼54%ï¼, high pressure back type ï¼14%ï¼, and pressure equalization field ï¼10%ï¼. High pressure front ï¼bottomï¼ type was the main ground situation causing the increase in PM2.5 concentration. There were two types of upper air conditions, namely, flat westerly flow type ï¼78%ï¼ and northwest flow type ï¼22%ï¼. The upper westerly flow type was the main upper air condition that caused the increase in PM2.5 concentration. ⣠The results of transport channels and potential source areas of PM2.5 with different pollution levels obtained by MS-PSCF and TDA were consistent. The main transport channels of PM2.5 were the northeast, southeast, and northwest channels, whereas the northeast and southeast channels were short-distance transport routes, which were the main routes causing the increase in PM2.5 concentration. The northwest channel was consistent with the northwest dust transport channel, belonging to long-distance transmission. The main potential source areas of PM2.5 pollution were located in the central and western parts of Hebei and the southeast part of Hebei, the northeast part of Henan and its junction with the southwest part of Shandong, and the southeast part of Shanxi.
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Stress is an emotional state caused by an unexpected external environmental change or stimulus, and several experiments have demonstrated its negative impact on ovarian function, ultimately affecting reproductive ability. Melatonin (MT) has been shown to facilitate oocyte maturation and enhance ovarian function by regulating mitochondrial function. However, the specific effect and underlying molecular mechanisms of MT on stress-induced ovarian dysfunction remain largely unknown. In this study, we established a mouse model of chronic unpredictable mild stress (CUMS) to investigate its impact on ovarian function. Our findings revealed that CUMS led to premature ovarian insufficiency (POI) in mice, characterized by a reduction in follicle numbers and decreased levels of anti-Müllerian hormone (AMH) and bone morphogenetic protein 15 (BMP15). Furthermore, CUMS caused decreased expression of mitochondrial fission protein 1 (FIS1) and enhanced level of mitochondrial fusion protein optic atrophy 1(OPA1), mitofusin1(MFN1), as well as nucleus-encoded protein succinate dehydrogenase complex A (SDHA), reflecting mitochondrial dyshomeostasis. Additionally, CUMS resulted in excessive autophagy and apoptosis. However, MT reversed these effects and improved ovarian damage. Importantly, the protective effects of MT were mediated through the inhibition of the eIF2α-AFT4 pathway. Overall, this study provides valuable insights into the treatment of POI caused by CUMS.
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BACKGROUND: Verticillium wilt, caused by the fungal pathogen Verticillium dahliae, is the most severe disease in cotton (Gossypium spp.), causing great lint losses worldwide. Disease management could be achieved in the field if genetically improved, resistant plants were used. However, the interaction between V. dahliae and cotton is a complicated process, and its molecular mechanism remains obscure. To understand better the defense response to this pathogen as a means for obtaining more tolerant cultivars, we monitored the transcriptome profiles of roots from resistant plants of G. barbadense cv. Pima90-53 that were challenged with V. dahliae. RESULTS: In all, 46,192 high-quality expressed sequence tags (ESTs) were generated from a full-length cDNA library of G. barbadense. They were clustered and assembled into 23126 unigenes that comprised 2661 contigs and 20465 singletons. Those unigenes were assigned Gene Ontology terms and mapped to 289 KEGG pathways. A total of 3027 unigenes were found to be homologous to known defense-related genes in other plants. They were assigned to the functional classification of plant-pathogen interactions, including disease defenses and signal transduction. The branch of "SAâNPR1âTGAâPR-1âDisease resistance" was first discovered in the interaction of cotton-V. dahliae, indicating that this wilt process includes both biotrophic and necrotrophic stages. In all, 4936 genes coding for putative transcription factors (TF) were identified in our library. The most abundant TF family was the NAC group (527), followed by G2-like (440), MYB (372), BHLH (331), bZIP (271) ERF, C3H, and WRKY. We also analyzed the expression of genes involved in pathogen-associated molecular pattern (PAMP) recognition, the activation of effector-triggered immunity, TFs, and hormone biosynthesis, as well as genes that are pathogenesis-related, or have roles in signaling/regulatory functions and cell wall modification. Their differential expression patterns were compared among mock-/inoculated- and resistant/susceptible cotton. Our results suggest that the cotton defense response has significant transcriptional complexity and that large accumulations of defense-related transcripts may contribute to V. dahliae resistance in cotton. Therefore, these data provide a resource for cotton improvement through molecular breeding approaches. CONCLUSIONS: This study generated a substantial amount of cotton transcript sequences that are related to defense responses against V. dahliae. These genomics resources and knowledge of important related genes contribute to our understanding of host-pathogen interactions and the defense mechanisms utilized by G. barbadense, a non-model plant system. These tools can be applied in establishing a modern breeding program that uses marker-assisted selections and oligonucleotide arrays to identify candidate genes that can be linked to valuable agronomic traits in cotton, including disease resistance.