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1.
Water Res ; 255: 121548, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38569357

RESUMO

Rhizoremediation of wetland plants is an environmentally friendly strategy for sediment phosphorous (P) removal, the basic underlying principle of which is the complex interactions between roots and microorganisms. This study investigated the immobilization and mobilization mechanisms of P in the rhizosphere of wetland plants using high-resolution spatial visualization techniques and metagenomic sequencing. Two-dimensional visualization of the spatial distribution of P, iron (Fe) and manganese (Mn) indicated that the sequestration of Fe-oxides rather than Mn-oxides caused the depletion of labile P, resulting in an increase in the Fe-adsorbed P fraction. Plants altered the rhizospheric environments and P-cycling microbial community to mobilize low-availability P from sediments. Mineral P solubilization and organic P mineralization were enhanced by local acidification and increased phosphatase activity, respectively. Microbial P mobilization also increased with increasing relative abundances of P solubilization and mineralization genes (gcd and phnW) and decreasing P transportation genes (ugpA, ugpB, and pit) genes in the rhizosphere. These processes led to the remobilization of 10.04 % of inorganic P, and 15.23 % of organic P, in the rhizosphere during the incubation period. However, the resupply of P via the above processes did not compensate for the depletion of rhizospheric P via root uptake and mineral sequestration. Our results provide novel insights into the mechanisms of rhizospheric P cycling, which will help to inform future phytoremediation strategies.

2.
J Phys Chem A ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635947

RESUMO

Herein, we report a computation study based on the density functional theory calculations to understand the mechanism and ligand effect of the base-stabilized dialumenes toward dihydrogen activation. Among all of the examined modes of dihydrogen activation using the base-stabilized dialumene, we found that the concerted 1,2-hydrogenation of the Al═Al double bond is kinetically more preferable. The concerted 1,2-hydrogenation of the Al═Al double bond adopts an electron-transfer model with certain asynchrony. That is, the initial electron donation from the H-H σ bonding orbital to the empty 3p orbital of the Al1 center is followed by the backdonation from the lone pair electron of the Al2 center to the H-H σ antibonding orbital. Combined with the energy decomposition analysis on the transition states of the concerted 1,2-hydrogenation of the Al═Al double bond and the topographic steric mapping analysis on the free dialumenes, we ascribe the higher reactivity of the aryl-substituted dialumene over the silyl-substituted analogue in dihydrogen activation to the stronger electron-withdrawing effect of the aryl group, which not only increases the flexibility of the Al═Al double bond but also enhances the Lewis acidity of the Al═Al core. Consequently, the aryl-substituted dialumene fragment suffers less geometric deformation, and the orbital interactions between the dialumene and dihydrogen moieties are more attractive during the 1,2-hydrogenation process. Moreover, our calculations also predict that the Al═Al double bond has a good tolerance with the stronger electron-withdrawing group (-CF3) and the weaker σ-donating N-heterocyclic carbene (NHC) analogue (e.g., triazol carbene and NHSi). The reactivity of the dialumene in dihydrogen activation can be further improved by introducing these groups as the supporting ligand and the stabilizing base on the Al═Al core, respectively.

3.
World J Orthop ; 15(2): 192-200, 2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38464349

RESUMO

The effectiveness of platelet-rich plasma (PRP) for the treatment of Achilles tendon disorders still needs to be evaluated through a series of prospective studies, but genomic analysis can reveal the existence of complementary PRP treatment options. Based on the 96 platelet activation-related genes in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, we performed Gene Ontology functional enrichment analysis and KEGG enrichment analysis, pathway correlation analysis, and enrichment mapping to determine the enrichment results of the gene set enrichment analysis and found that the cAMP signalling pathway may be the key to enhancing the effectiveness of PRP treatment. The cAMP signalling pathway interacts with the Rap1 signalling pathway and cGMP-PKG signalling pathway to mediate the entire pathophysiological process of Achilles tendon disease. Moreover, ADCY1-9 may be the key to the activation of the cAMP signalling network. Further based on the data in the Gene Expression Omnibus database, it was found that ADCY4 and ADCY7 may be the players that play a major role, associated with the STAT4-ADCY4-LAMA5 axis and the GRbeta-ADCY7-SEMA3C axis, which is expected to be a complementary target for enhancing the efficacy of PRP in the treatment of Achilles tendon disease.

4.
Huan Jing Ke Xue ; 45(2): 1058-1068, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471943

RESUMO

In order to explore the characteristics and sources of heavy metal pollution in cultivated soil around a red mud yard in Chongqing, the content and spatial distribution characteristics of eight heavy metal elements (Cd, Cr, Hg, Ni, Pb, As, Cu, and Zn) in the soil were analyzed, and the single factor pollution index method and Nemerow comprehensive pollution index method were used to evaluate the characteristics of heavy metal pollution in soil. On the basis of correlation analysis, the APCS-MLR and PMF models were used to quantitatively analyze the sources of heavy metals. The results showed that the average contents of the other seven heavy metal elements were higher than the background values of Chongqing soil, except for that of Cr. The heavy metals Cd, Hg, and As were moderately polluted, and Pb, Cu, Ni, and Zn were mildly polluted. The spatial distribution pattern of Cr, Ni, Pb, Cu, and Zn in the soil was similar, and there was a very significant positive correlation between them (P < 0.01). The spatial distribution characteristics of Cd, Hg, and As were significantly different, and there was no significant correlation between them (P > 0.05). The source apportionment showed that the sources of heavy metals in the soil in the study area were relatively complex, and the APCS-MLR and PMF models could identify the same four pollution sources, namely red mud yard percolation emission and natural sources, thermal power generation emission sources, agricultural activities and natural sources, and non-ferrous metal smelting emission sources. There was little difference in the results of source apportionment between the two models. The contribution rates of the four pollution sources in the APCS-MLR model were 51.8%, 18.0%, 15.9%, and 14.3%, respectively, whereas those in the PMF model were 45.9%, 12.8%, 21.5%, and 19.8%, respectively.

5.
Adv Sci (Weinh) ; : e2308710, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477453

RESUMO

The synthesis of allenyl boronates is an important yet challenging topic in organic synthesis. Reported herein is an NHC-gold-catalyzed 1,3-H shift toward allenyl boronates synthesis from simple propargylic B(MIDA)s. Mechanistic studies suggest dual roles of the boryl moiety in the reaction: to activate the substrate for isomerization and at the same time, to prevent the allene product from further isomerization. These effects should be a result of α-anion stabilization and α-cation destabilization conferred by the B(MIDA) moiety, respectively. The NHC-Au catalyst, which is commercially available, is also found to be reactive in alkyne-to-1,3-diene isomerization reactions in an atom-economic and base-free manner.

6.
Sci Rep ; 14(1): 5976, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472256

RESUMO

We performed this cohort study to investigate whether the myocardial bridge (MB) affects the fat attenuation index (FAI) and to determine the optimal cardiac phase to measure the volume and the FAI of pericoronary adipose tissue (PCAT). The data of 300 patients who were diagnosed with MB of the left anterior descending (LAD) coronary artery were retrospectively analyzed. All of patients were divided into the MB group and the MB with atherosclerosis group. In addition, 104 patients with negative CCTA results were enrolled as the control group. There was no significant difference between FAI values measured in systole and diastole (P > 0.05). There was no significant difference in FAI among the MB group, the MB with atherosclerosis group, and the control group (P > 0.05). In MB with atherosclerosis group, LAD stenosis degree (< 50%) (OR = 0.186, 95% CI 0.036-0.960; P = 0.045) and MB located in the distal part of LAD opening (OR = 0.880, 95% CI 0.789-0.980; P = 0.020) were protective factors of FAI value. A distance (from the LAD opening to the proximal point of the MB) of 29.85 mm had the highest predictive value for abnormal FAI [area under the curve (AUC), 0.798], with a sensitivity of 81.1% and a specificity of 74.6%.


Assuntos
Aterosclerose , Doença da Artéria Coronariana , Ponte Miocárdica , Humanos , Angiografia Coronária/métodos , Estudos de Coortes , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Vasos Coronários , Tecido Adiposo
7.
Huan Jing Ke Xue ; 45(3): 1428-1438, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471858

RESUMO

To understand the water pollution status and environmental risks of Changshou Lake, the concentrations of heavy metals (Cr, Cu, Zn, As, Cd, and Pb) in the water were collected and analyzed during different seasons. The study investigated temporal and spatial variations, distribution characteristics, pollution levels, and health risks associated with heavy metals in Changshou Lake. The results showed that all six heavy metals were below than the Class Ⅰ standard of the Surface Water Environmental Quality Standard (GB 3838-2002), but recent years have witnessed an increasing trend, with Cu, As, and Pb showing a significant increase (P<0.05). The temporal and spatial distributions of these heavy metals were different. Temporally, Cr and Cd concentrations in surface water were higher in summer, As and Zn were higher in spring, and Pb and Cu were higher in autumn and winter. Spatially, the concentrations of Cr, As, Cu, Zn, and Pb showed higher concentrations in the southern outlet of the reservoir, the northwestern Longxi River inlet, and the central part of the reservoir, whereas Cd was higher in the northern stagnant area. The overall levels of heavy metals in the water body of Changshou Lake were low, with Cr and Cu slightly polluted, while other heavy metals were identified as having an insignificant pollution level. Drinking water was the primary exposure pathway to carcinogenic and non-carcinogenic heavy metals in surface water bodies. The health risk values of Cr and As in water bodies were high, ranging from 6.2×10-10 to 3.0×10-4 and 5.1×10-8 to 3.9×10-5, respectively. The corresponding contribution rates for children and adults to the total health risk were high, with Cr accounting for 87.18% and 87.20%, respectively, while As accounted for 12.73% and 12.71%, respectively. Therefore, it is crucial to prioritize environmental risks associated with Cr and Cu, as well as the health risks associated with Cr and As in Changshou Lake These findings provide a scientific foundation for water pollution control and environmental quality improvement in Changshou Lake, and rational development and utilization of water resources.


Assuntos
Água Potável , Metais Pesados , Poluentes Químicos da Água , Cádmio , China , Monitoramento Ambiental , Sedimentos Geológicos , Lagos/análise , Chumbo , Metais Pesados/análise , Medição de Risco , Poluentes Químicos da Água/análise , Humanos , Criança , Adulto
8.
Quant Imaging Med Surg ; 14(3): 2213-2224, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38545056

RESUMO

Background: There is an increasing evidence that pulmonary vein (PV) enlargement is associated with atrial fibrillation (AF); however, the predictive value of PV enlargement in AF recurrence remains unclear. This study sought to evaluate whether PV volume quantification derived from cardiac computed tomographic angiography (CCTA) could serve as a predictive indicator of the success of the catheter ablation (CA) procedure. Methods: The data of 160 patients diagnosed with AF who underwent both CCTA and CA treatments from January to June 2020 were retrospectively examined; the CCTA was conducted before the CA surgery. The study focused on documenting the PV structure, and the volume of the PV and left atrium (LA). The clinical, CCTA, and echocardiographic predictors of the recurrence and no-recurrence groups were compared. A multivariable logistic regression analysis was performed to adjust for confounders. Receiver operating characteristic (ROC) curves were analyzed to assess the predictive performance of the predictors of AF recurrence. Results: Of the 160 patients [55.6% male, 62.00 (55.25-68.00) years, 23.1% with persistent AF], 45 (28.1%) experienced AF recurrence within a one-year period. Notably, patients with AF recurrence had elevated CHADS2 scores (P=0.020) and increased LA and PV volumes (P<0.05). Patients with persistent AF (n=37) had significantly larger LA volume indexes (P<0.001) than those with paroxysmal AF, but there was no difference between the two groups in terms of the PV maximum volume index (P=0.200). Moreover, the PV maximum volume index [odds ratio (OR): 1.244, 95% confidence interval (CI): 1.008-1.536, P=0.042] and the LA minimum volume index (OR: 1.026, 95% CI: 1.001-1.052, P=0.038) were found to be significant predictors of AF recurrence. The ROC curves revealed that the PV maximum volume index threshold for predicting AF recurrence was 7.13 mL/m2, with a sensitivity of 84.4% and a specificity of 34.8% [area under the curve (AUC): 0.635, 95% CI: 0.540-0.730, P=0.008], and the LA minimum volume index threshold for predicting AF recurrence was 46.16 mL/m2, with a sensitivity of 88.9% and a specificity of 31.3% (AUC: 0.629, 95% CI: 0.534-0.723, P=0.012). A sub-analysis of patients with a lower left atrial dimension (LAD ≤38 mm in females, LAD ≤40 mm in males, n=120) demonstrated that the PV maximum volume index was a noteworthy indicator of AF recurrence (OR: 1.443: 95% CI: 1.145-1.820, P=0.002). Conversely, no significant correlation between AF recurrence and the LA volume index was found. The AUC value for the PV maximum volume index predictive of recurrent AF was 0.680 (95% CI: 0.577-0.781, P=0.003), with a sensitivity of 75.8%, specificity of 54%, and the cut-off value of the maximum AUC was 7.89 mL/m2. Conclusions: PV volume, derived from CCTA, may help to predict the recurrence of AF after CA, and is superior to the LA size in patients with less pronounced LA enlargement.

9.
J Transl Med ; 22(1): 316, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549133

RESUMO

BACKGROUND: Propofol is a widely used anesthetic and sedative, which has been reported to exert an anti-inflammatory effect. TLR4 plays a critical role in coordinating the immuno-inflammatory response during sepsis. Whether propofol can act as an immunomodulator through regulating TLR4 is still unclear. Given its potential as a sepsis therapy, we investigated the mechanisms underlying the immunomodulatory activity of propofol. METHODS: The effects of propofol on TLR4 and Rab5a (a master regulator involved in intracellular trafficking of immune factors) were investigated in macrophage (from Rab5a-/- and WT mice) following treatment with lipopolysaccharide (LPS) or cecal ligation and puncture (CLP) in vitro and in vivo, and peripheral blood monocyte from sepsis patients and healthy volunteers. RESULTS: We showed that propofol reduced membrane TLR4 expression on macrophages in vitro and in vivo. Rab5a participated in TLR4 intracellular trafficking and both Rab5a expression and the interaction between Rab5a and TLR4 were inhibited by propofol. We also showed Rab5a upregulation in peripheral blood monocytes of septic patients, accompanied by increased TLR4 expression on the cell surface. Propofol downregulated the expression of Rab5a and TLR4 in these cells. CONCLUSIONS: We demonstrated that Rab5a regulates intracellular trafficking of TLR4 and that propofol reduces membrane TLR4 expression on macrophages by targeting Rab5a. Our study not only reveals a novel mechanism for the immunomodulatory effect of propofol but also indicates that Rab5a may be a potential therapeutic target against sepsis.


Assuntos
Propofol , Sepse , Camundongos , Humanos , Animais , Propofol/farmacologia , Propofol/uso terapêutico , Propofol/metabolismo , Receptor 4 Toll-Like/metabolismo , Modelos Animais de Doenças , Macrófagos/metabolismo , Sepse/complicações , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo
10.
Heliyon ; 10(6): e28075, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38533028

RESUMO

The evolution of the hotel industry's corporate environmental performance cannot be realized without employees acting in an environmentally friendly manner, such as low carbon behaviour. However, a thorough analysis of the factors influencing employees' low-carbon behaviour and hotels' corporate environmental performance has not yet been done. To overcome this literature gap and envision the social identity theory, this study evaluated how employees' green self-efficacy, environmental awareness, and perceived corporate environmental responsibility facilitate staff low carbon behaviour. Also, the study explored the moderation role of employees' moral reflectiveness. Through a purposive sampling technique, data was collected from 455 employees in the hotel industry in South Africa. The partial least squares structural equation model method examined the proposed hypothesis. The empirical findings revealed that: (1) employees' green self-efficacy, environmental awareness, and perceived corporate environmental responsibility positively influence their low carbon behaviour. (2) Employees' low carbon behaviour directly and positively affected hotels' corporate environmental performance. (3) The outcome supported the moderation effect of employees' moral reflectiveness on the linkage between green self-efficacy and low-carbon behaviour. The practical and theoretical implications are discussed. The limitations and areas of future research are further outlined.

11.
Environ Res ; 251(Pt 2): 118734, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493854

RESUMO

Mercury (Hg), especially in the form of methylmercury (MeHg), poses a significant threat to both organisms and the environment due to its extreme toxicity. While methylation process of Hg in sediments has been extensively studied, recognition of its associated risks and mechanisms during cyanobacterial blooms remains limited. This study investigated the distribution characteristics of Hg and MeHg in sediments of Taihu Lake, China. The concentration of Hg and MeHg varied within the range of 96.0-212.0 ng g-1 and 0.1-0.5 ng g-1, respectively. Higher ecological risks of Hg were found in algal-dominated regions compared to macrophyte areas. The significant correlations observed between Hg, MeHg, and algal-derived dissolved organic matter (ADOM) components C1 and C2 in algal-dominated regions indicate a close association between ADOM components and the Hg methylation process. These components are involved in the absorption or complexation of Hg, participate in redox reactions, and modulate microbial activity. The dsrB gene in sulfate-reducing bacteria (SRB) was found to accelerate the metabolic pathways of Hg methylation. These findings indicate that ADOM could enhance the methylation process of Hg during cyanobacterial blooms, which warrants attention.

12.
BMC Med Res Methodol ; 24(1): 69, 2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38494505

RESUMO

BACKGROUND: Intensive longitudinal data (ILD) collected in near real time by mobile health devices provide a new opportunity for monitoring chronic diseases, early disease risk prediction, and disease prevention in health research. Functional data analysis, specifically functional principal component analysis, has great potential to abstract trends in ILD but has not been used extensively in mobile health research. OBJECTIVE: To introduce functional principal component analysis (fPCA) and demonstrate its potential applicability in estimating trends in ILD collected by mobile heath devices, assessing longitudinal association between ILD and health outcomes, and predicting health outcomes. METHODS: fPCA and scalar-to-function regression models were reviewed. A case study was used to illustrate the process of abstracting trends in intensively self-measured blood glucose using functional principal component analysis and then predicting future HbA1c values in patients with type 2 diabetes using a scalar-to-function regression model. RESULTS: Based on the scalar-to-function regression model results, there was a slightly increasing trend between daily blood glucose measures and HbA1c. 61% of variation in HbA1c could be predicted by the three preceding months' blood glucose values measured before breakfast (P < 0.0001, [Formula: see text]). CONCLUSIONS: Functional data analysis, specifically fPCA, offers a unique tool to capture patterns in ILD collected by mobile health devices. It is particularly useful in assessing longitudinal dynamic association between repeated measures and outcomes, and can be easily integrated in prediction models to improve prediction precision.


Assuntos
Diabetes Mellitus Tipo 2 , Telemedicina , p-Cloroanfetamina/análogos & derivados , Humanos , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/terapia , Glicemia , Hemoglobinas Glicadas , Análise de Componente Principal , Avaliação de Resultados em Cuidados de Saúde
13.
Opt Express ; 32(3): 2959-2971, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297531

RESUMO

The diffuse attenuation coefficient (Kd) is known to be closely related to the light transmittance of sea ice, which plays a critical role in the energy balance and biological processes of the upper ocean. However, the commercial instruments cannot easily measure Kd in sea ice because sea ice is a solid. The authors of this study are developing an instrument with a high spectral solution to measure the irradiance profile of sea ice and the irradiance in the atmosphere. Three Kd experiments were carried out, including two in-situ experiments in the Liaodong Bay and one in the laboratory. The results showed that the Kd of the sea ice varied with depth, and the values in adjacent sea ice layers differed by up to 2 times. In addition, due to changes in the climate environment, the Kd of sea ice showed temporal variations. For example, there was a 1.38-fold difference in the Kd values of the surface layer of sea ice at different times in 2022. The values in different sea ice layers also showed different trends over time, and the coefficient of determination (R2) of Kd between adjacent layers over time was as low as 0.008. To explain the driving mechanism of spatio-temporal variability of Kd, an additional experiment focusing on the physical microstructure of sea ice was conducted in Liaodong Bay in 2022. The result shows that the change in air bubbles in the sea ice may be the main the reason for the change in Kd. For example, when the sea ice was exchanging brine and bubbles with the atmosphere above and the seawater below, the highly absorbent particles in it tend to remain in their original position. Considering that the total absorption coefficient changed slightly, the bubbles with the characteristic of intense scattering were found to be the main factor influencing the Kd changes. This conclusion is supported by the fact that the value of R2 between the bubbles and Kd was 0.52. If climatic changes have led to an increase in the volume of bubbles, the more bubbles will increase the scattering properties of sea ice and lead to an increase in Kd. Conversely, the reduced bubble volume would reduce the scattering properties of sea ice, which in turn would reduce Kd.

14.
Clin Physiol Funct Imaging ; 44(3): 251-259, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38356324

RESUMO

PURPOSE: To quantitatively investigate the effect of myocardial bridge (MB) in the left anterior descending artery (LAD) on the fractional flow reserve (FFR). MATERIALS AND METHODS: Three-hundred patients with LAD MB who had undergone coronary artery CT angiography (CCTA) were retrospectively enroled, and 104 normal patients were enroled as the control. The CCTA-derived fractional flow reserve (FFRCT) was measured at the LAD 10 mm proximal (FFR1) and 20-40 mm distal (FFR3) to the MB and at the MB location (FFR2). RESULTS: FFR2 and FFR3 of the MB (with BM only) and MBLA (with both MB and atherosclerosis) groups were significantly (p < 0.01) lower than those of the control. The FFR3 distal to the MB was significantly lower (p < 0.01) than that of the control. The FFRCT of the whole LAD in the MBLA group was significantly (p < 0.05) lower than that of the MB and control group (p < 0.05). MB length (OR 1.061) and MB muscle index (odds ratio or OR 1.007) were two risk factors for abnormal FFRCT, and MB length was a significant independent risk factor for abnormal FFRCT (OR = 1.077). LAD stenosis degree was a risk factor for abnormal FFRCT values (OR 3.301, 95% confidence interval [CI] 1.441-7.562, p = 0.005) and was also a significant independent risk factor (OR = 3.369, 95% CI: 1.392-8.152; p = 0.007) for abnormal FFRCT. CONCLUSION: MB significantly affects the FFRCT of distal coronary artery. For patients with MB without atherosclerosis, the MB length is a risk factor significantly affecting FFRCT, and for patients with MB accompanied by atherosclerosis, LAD stenotic severity is an independent risk factor for FFRCT.


Assuntos
Aterosclerose , Doença da Artéria Coronariana , Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Ponte Miocárdica , Humanos , Angiografia por Tomografia Computadorizada/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Vasos Coronários/diagnóstico por imagem , Estudos Retrospectivos , Ponte Miocárdica/diagnóstico por imagem , Valor Preditivo dos Testes , Estenose Coronária/diagnóstico por imagem , Angiografia Coronária/métodos , Índice de Gravidade de Doença
15.
Mol Breed ; 44(3): 20, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38404720

RESUMO

Nonapomictic citrus tetraploids are desirable in citrus breeding for the production of triploid, seedless varieties, and polyploid rootstocks. However, only a few lines have been reported, and they were all generated using chemical methods. A 2x + 4 × cytochimera of the nonapomictic citrus variety 'Orah' mandarin, which developed from a bud mutant, was found due to its morphology differing from that of diploid plants and characterised via ploidy analysis combining flow cytometry and chromosome observation. The chimaera was stable, and there were 1.86-1.90 times as tetraploid cells as diploid cells. Anatomical structure observation revealed that the 'Orah' chimaera may be a periclinal chimaera with diploid cells in the L1 layer and tetraploid cells in the L2 and L3 layers. The chimaera showed some typical traits of polyploid plants, including thicker shoots, wider and thicker leaves, larger flowers and fruits, and fewer but larger seeds in fruits than in diploid plants. Almost all the seeds of the chimaera were monoembryonic. Most of the self-pollinated progenies of the chimaera were identified as tetraploids, and some triploid, pentaploid, and hexaploid plants were found. As a female, the chimaera produced allotriploids when crossed with Australian finger lime. In addition, 6 plants developed from polyembryonic seeds of the chimaera were identified as sexual tetraploid progenies with low-level recombinant genomes. Therefore, the 'Orah' 2x + 4 × chimaera can be used as a female parent to produce hybrid triploid and tetraploid citrus plants with high efficiency. Identification of the chimaera demonstrated that tetraploid citrus plants, especially nonapomictic varieties, can be generated from shoot bud mutants. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01456-x.

16.
Pediatr Blood Cancer ; 71(5): e30928, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38418934

RESUMO

OBJECTIVES: This study aims to analyze the behavior and treatment of adenoid cystic carcinoma (AdCC) in the pediatric and young adult population and to identify factors affecting overall survival (OS). MATERIALS AND METHODS: The study analyzed salivary gland malignancies in patients aged 0-21 with AdCC histology using the National Cancer Database from 2004 to 2018. RESULTS: A total of 72 patients (59.7% parotid, 36.1% submandibular, 1.4% sublingual, 2.8% unspecified) met criteria. Median age was 18 years [range: 0-21]. High-grade dysplasia was present in 67% of cases. Therapy consisted of primary surgery for all cases, regional lymph node dissection (LND) (74%), radiotherapy (71%), chemotherapy (8%), and chemoradiation (7%). The 5-year OS rate was 93.2% [95% confidence interval (CI): 86.9%-99.9%], respectively. Patients who underwent associated LND had improved OS (p = .0083, log-rank test) with a 5-year OS at 82.4% [95% CI: 66.1%-100%] versus 97.6% [95% CI: 93.0%-100%]. A significant difference in OS was found with unfavorable outcomes after positive marginal status: 5-year OS 84.1% [95% CI: 71.0%-99.7%] versus 100% [95% CI: 100%]; p < .001. Adjuvant therapy did not seem to impact the outcome. CONCLUSION: This study confirms that AdCC in children and young adults has an overall good prognosis despite frequent high grade. It suggests that cervical LND may be of importance, but the value of systematic adjuvant therapy is not confirmed. These findings emphasize the importance and relevance of population-based studies in shaping clinical practice and informing the design of future prospective investigations.


Assuntos
Carcinoma Adenoide Cístico , Neoplasias das Glândulas Salivares , Humanos , Adulto Jovem , Criança , Adolescente , Carcinoma Adenoide Cístico/patologia , Carcinoma Adenoide Cístico/radioterapia , Glândula Submandibular/patologia , Esvaziamento Cervical , Estudos Retrospectivos , Prognóstico
17.
J Dig Dis ; 25(1): 36-43, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38323705

RESUMO

OBJECTIVES: We aimed to explore the efficacy and safety of tailored therapy guided by genotypic resistance in the first-line treatment of Helicobacter pylori (H. pylori) infection in treatment-naive patients. METHODS: Gastric mucosal specimens were taken during gastroscopy, and main mutations of clarithromycin- and levofloxacin-resistant genes were detected by polymerase chain reaction (PCR). Sensitive antibiotics were selected individually for treating H. pylori infection with tailored bismuth-containing quadruple therapy (BQT) consisting of esomeprazole 20 mg twice daily, bismuth potassium citrate 220 mg twice daily, amoxicillin 1 g twice daily, and clarithromycin 500 mg twice daily, or levofloxacin 500 mg once daily, or metronidazole 400 mg four times daily. Safety and patient compliance were assessed 1-3 days after eradication. Treatment outcome was evaluated by urea breath test 4-8 weeks after eradication. RESULTS: One hundred and thirty-two treatment-naive patients with H. pylori infection were included. PCR results suggested resistance rates of 47.7% and 34.9% for clarithromycin and levofloxacin, respectively, and a dual resistance rate of 18.2%. Eradication rates of tailored BQT were 87.1% and 95.8% by intention-to-treat (ITT) analysis and per-protocol (PP) analysis, respectively. There was no statistically significant difference in the efficacy of 7-day clarithromycin-containing, 7-day levofloxacin-containing, and 14-day full-dose metronidazole-containing BQT (ITT analysis: P = 0.488; PP analysis: P = 0.833). The incidence of adverse events was 19.7%, and patient compliance was 97.7%. CONCLUSION: Tailored BQT guided by genotypic resistance can achieve satisfactory efficacy, safety, and patient compliance in the first-line treatment of H. pylori infection.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Infecções por Helicobacter/tratamento farmacológico , Claritromicina/farmacologia , Claritromicina/uso terapêutico , Levofloxacino/efeitos adversos , Helicobacter pylori/genética , Bismuto/uso terapêutico , Metronidazol/uso terapêutico , Quimioterapia Combinada , Antibacterianos/efeitos adversos , Amoxicilina/uso terapêutico , Resultado do Tratamento , Reação em Cadeia da Polimerase
18.
Genome Res ; 34(1): 20-33, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38190638

RESUMO

As an essential part of the central nervous system, white matter coordinates communications between different brain regions and is related to a wide range of neurodegenerative and neuropsychiatric disorders. Previous genome-wide association studies (GWASs) have uncovered loci associated with white matter microstructure. However, GWASs suffer from limited reproducibility and difficulties in detecting multi-single-nucleotide polymorphism (multi-SNP) and epistatic effects. In this study, we adopt the concept of supervariants, a combination of alleles in multiple loci, to account for potential multi-SNP effects. We perform supervariant identification and validation to identify loci associated with 22 white matter fractional anisotropy phenotypes derived from diffusion tensor imaging. To increase reproducibility, we use United Kingdom (UK) Biobank White British (n = 30,842) data for discovery and internal validation, and UK Biobank White but non-British (n = 1927) data, Europeans from the Adolescent Brain Cognitive Development study (n = 4399) data, and Europeans from the Human Connectome Project (n = 319) data for external validation. We identify 23 novel loci on the discovery set that have not been reported in the previous GWASs on white matter microstructure. Among them, three supervariants on genomic regions 5q35.1, 8p21.2, and 19q13.32 have P-values lower than 0.05 in the meta-analysis of the three independent validation data sets. These supervariants contain genetic variants located in genes that have been related to brain structures, cognitive functions, and neuropsychiatric diseases. Our findings provide a better understanding of the genetic architecture underlying white matter microstructure.


Assuntos
Substância Branca , Humanos , Adolescente , Substância Branca/diagnóstico por imagem , Imagem de Tensor de Difusão , Estudo de Associação Genômica Ampla , Reprodutibilidade dos Testes , Encéfalo/diagnóstico por imagem
19.
Nat Rev Mol Cell Biol ; 25(5): 359-378, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38182846

RESUMO

A growing class of small RNAs, known as tRNA-derived RNAs (tdRs), tRNA-derived small RNAs or tRNA-derived fragments, have long been considered mere intermediates of tRNA degradation. These small RNAs have recently been implicated in an evolutionarily conserved repertoire of biological processes. In this Review, we discuss the biogenesis and molecular functions of tdRs in mammals, including tdR-mediated gene regulation in cell metabolism, immune responses, transgenerational inheritance, development and cancer. We also discuss the accumulation of tRNA-derived stress-induced RNAs as a distinct adaptive cellular response to pathophysiological conditions. Furthermore, we highlight new conceptual advances linking RNA modifications with tdR activities and discuss challenges in studying tdR biology in health and disease.


Assuntos
RNA de Transferência , Animais , RNA de Transferência/metabolismo , RNA de Transferência/genética , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Regulação da Expressão Gênica , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/metabolismo
20.
Heliyon ; 10(2): e24227, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38293505

RESUMO

Background: In the context of sepsis patients, hypertension has a significant impact on the likelihood of developing sepsis-associated acute kidney injury (S-AKI), leading to a considerable burden. Moreover, sepsis is responsible for over 50 % of cases of acute kidney injuries (AKI) and is linked to an increased likelihood of death during hospitalization. The objective of this research is to develop a dependable and strong nomogram framework, utilizing the variables accessible within the first 24 h of admission, for the anticipation of S-AKI in sepsis patients who have hypertension. Methods: In this study that looked back, a total of 462 patients with sepsis and high blood pressure were identified from Nanfang Hospital. These patients were then split into a training set (consisting of 347 patients) and a validation set (consisting of 115 patients). A multivariate logistic regression analysis and a univariate logistic regression analysis were performed to identify the factors that independently predict S-AKI. Based on these independent predictors, the model was constructed. To evaluate the efficacy of the designed nomogram, several analyses were conducted, including calibration curves, receiver operating characteristics curves, and decision curve analysis. Results: The findings of this research indicated that diabetes, prothrombin time activity (PTA), thrombin time (TT), cystatin C, creatinine (Cr), and procalcitonin (PCT) were autonomous prognosticators for S-AKI in sepsis individuals with hypertension. The nomogram model, built using these predictors, demonstrated satisfactory discrimination in both the training (AUC = 0.823) and validation (AUC = 0.929) groups. The S-AKI nomogram demonstrated superior predictive ability in assessing S-AKI within the hypertension grade I (AUC = 0.901) set, surpassing the hypertension grade II (AUC = 0.816) and III (AUC = 0.810) sets. The nomogram exhibited satisfactory calibration and clinical utility based on the calibration curve and decision curve analysis. Conclusion: In patients with sepsis and high blood pressure, the nomogram that was created offers a dependable and strong evaluation for predicting S-AKI. This evaluation provides valuable insights to enhance individualized treatment, ultimately resulting in improved clinical outcomes.

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