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1.
Anal Chem ; 96(16): 6255-6263, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38588398

RESUMO

Molecular Rotational Resonance (MRR) spectroscopy is a uniquely precise tool for the determination of molecular structures of volatile compounds in mixtures, as the characteristic rotational transition frequencies of a molecule are extremely sensitive to its 3D structure through the moments of inertia in a three-dimensional coordinate system. This enables identification of the compounds based on just a few parameters that can be calculated, as opposed to, for example, mass spectrometric data, which often require expert analysis of 10-20 different signals and the use of many standards/model compounds. This paper introduces a new sampling technique for MRR, laser-induced acoustic desorption (LIAD), to allow the vaporization of nonvolatile and thermally labile analytes without the need for excessive heating or derivatization. In this proof-of-concept study, LIAD was successfully coupled to an MRR instrument to conduct measurements on seven compounds with differing polarities, molecular weights, and melting and boiling points. Identification of three isomers in a mixture was also successfully performed using LIAD/MRR. Based on these results, LIAD/MRR is demonstrated to provide a powerful approach for the identification of nonvolatile and/or thermally labile analytes with molecular weights up to 600 Da in simple mixtures, which does not require the use of reference compounds. In the future, applications to more complex mixtures, such as those relevant to pharmaceutical research, and quantitative aspects of LIAD/MRR will be reported.

2.
Breast Cancer Res Treat ; 206(2): 397-410, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38771398

RESUMO

PURPOSE: To investigate the prognostic significance of lymphovascular invasion in invasive breast cancer and the value of using specific vascular endothelial markers to further classify lymphovascular invasion. METHODS: We collected 2124 patients with invasive breast cancer who were hospitalized at the First Hospital of Dalian Medical University from 2012 to 2020. Statistical methods were used to investigate the relationship between lymphovascular invasion and clinicopathological characteristics of breast cancer, and the correlation between lymphovascular invasion on overall survival (OS) and disease-free survival (DFS) of various categories of breast cancers. Immunohistochemical staining of breast cancer samples containing lymphovascular invasion using specific vascular endothelial markers D2-40 and CD34 was used to classify lymphovascular invasion and to investigate the relationship between lymphovascular invasion and breast cancer progression. RESULTS: There was a high correlation between lymphovascular invasion and T stage, N stage and nerve invasion. Survival analyses showed that patients with lymphovascular invasion, especially luminal B, triple-negative, and Her-2 overexpression breast cancer patients, had poorer OS and DFS prognosis, and that lymphovascular invasion was an independent prognostic factor affecting OS and DFS in breast cancer. The immunohistochemical staining results showed that positive D2-40 staining of lymphovascular invasion was linked to the N stage and localized recurrence of breast cancer. CONCLUSION: Lymphovascular invasion is associated with aggressive clinicopathological features and is an independent poor prognostic factor in invasive breast cancer. Breast cancer localized recurrence rate and lymph node metastases are influenced by lymphatic vessel invasion. Immunohistochemical techniques should be added to the routine diagnosis of lymphovascular invasion.


Assuntos
Neoplasias da Mama , Metástase Linfática , Invasividade Neoplásica , Humanos , Feminino , Neoplasias da Mama/patologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/metabolismo , Neoplasias da Mama/classificação , Pessoa de Meia-Idade , Estudos Retrospectivos , Prognóstico , Metástase Linfática/patologia , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Estadiamento de Neoplasias , Recidiva Local de Neoplasia/patologia , Intervalo Livre de Doença , Receptor ErbB-2/metabolismo , Vasos Linfáticos/patologia
3.
Plant Biotechnol J ; 22(3): 774-784, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37942846

RESUMO

Flowering time is of great agricultural importance and the timing and extent of flowering usually determines yield and availability of flowers, fruits and seeds. Identification of genes determining flowering has important practical applications for tomato breeding. Here we demonstrate the roles of the FANTASTIC FOUR (FAF) gene family in regulating tomato flowering time. In this plant-specific gene family, SlFAF1/2a shows a constitutive expression pattern during the transition of the shoot apical meristem (SAM) from vegetative to reproductive growth and significantly influences flowering time. Overexpressing SlFAF1/2a causes earlier flowering compared with the transformations of other genes in the FAF family. SlFAF1/2c also positively regulates tomato flowering, although to a lesser extent. The other members of the SlFAF gene family, SlFAF1/2b, SlFAF3/4a and SlFAF3/4b, are negative regulators of tomato flowering and faf1/2b, faf3/4a and faf3/4b single mutants all display early flowering. We generated a series of early flowering mutants using the CRISPR/Cas9 editing system, and the faf1/2b faf3/4a faf3/4b triple mutant flowering earliest compared with other mutants. More importantly, these mutants show no adverse effect on yield. Our results have uncovered the role of the FAF gene family in regulating tomato flowering time and generated early flowering germplasms for molecular breeding.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sistemas CRISPR-Cas/genética , Melhoramento Vegetal , Mutação/genética , Flores , Regulação da Expressão Gênica de Plantas/genética
4.
J Exp Bot ; 75(11): 3322-3336, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38506421

RESUMO

Modern tomatoes produce colorful mature fruits, but many wild tomato ancestors form green or gray green ripe fruits. Here, tomato cultivar 'Lvbaoshi' (LBS) that produces green ripe fruits was found to contain three recessive loci responsible for fruit development. The colorless peel of LBS fruits was caused by a 603 bp deletion in the promoter of SlMYB12. The candidate genes of the remaining two loci were identified as STAY-GREEN 1 (SlSGR1) and PHYTOENE SYNTHASE 1 (SlPSY1). SGR1 and PSY1 co-suppression by RNAi converted the pink fruits into green ripe fruits in transgenic plants. An amino acid change in PSY1 and a deletion in the promoter of SGR1 were also identified in several wild tomatoes bearing green or gray ripe fruits. Overexpression of PSY1 from green ripe fruit wild tomatoes in LBS plants could only partially rescue the green ripe fruit phenotype of LBS, and transgenic lines expressing ProSGR1::SGR1 from Solanum pennellii also failed to convert purple-flesh into red-flesh fruits. This work uncovers a novel regulatory mechanism by which SlMYB12, SlPSY1, and SlSGR1 control fruit color in cultivated and some wild tomato species.


Assuntos
Alquil e Aril Transferases , Frutas , Geranil-Geranildifosfato Geranil-Geraniltransferase , Proteínas de Plantas , Solanum lycopersicum , Solanum lycopersicum/genética , Frutas/genética , Frutas/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Geranil-Geranildifosfato Geranil-Geraniltransferase/genética , Geranil-Geranildifosfato Geranil-Geraniltransferase/metabolismo , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Mutação , Plantas Geneticamente Modificadas/genética , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
5.
Plant Cell ; 33(10): 3293-3308, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34338777

RESUMO

The degree of stigma exsertion has a major influence on self-pollination efficiency in tomato, and its improvement is essential for raising productivity and for fixing advantageous traits in cultivated tomato. To study the evolution of stigma exsertion degree in tomato, we searched for genes associated with this trait and other aspects of flower morphology, including the lengths of anthers, styles, and ovaries. We performed a genome-wide association on 277 tomato accessions and discovered a novel stigma exsertion gene (SE3.1). We reannotated the structure of the gene, which encodes a C2H2-type zinc finger transcription factor. A mutation of the lead single nucleotide polymorphism creates a premature termination codon in SE3.1 and an inserted stigma in cultivated tomatoes. SE3.1 is essential for the conversion of flush stigmas to inserted stigmas. This conversion has a major impact on the rate of self-fertilization. Intriguingly, we found that both SE3.1 and Style2.1 contribute to the transition from stigma exsertion to insertion during the domestication and improvement of tomato. Style2.1 controls the first step of exserted stigmas to flush stigmas, and SE3.1 controls the second step of flush stigmas to inserted stigmas. We provide molecular details for the two-step process that controls the transition from stigma exsertion to insertion, which is of great agronomic importance in tomato.


Assuntos
Estudo de Associação Genômica Ampla , Proteínas de Plantas/genética , Polinização/genética , Solanum lycopersicum/fisiologia , Fatores de Transcrição/genética , Solanum lycopersicum/genética , Mutação , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo
6.
J Nutr ; 154(7): 1994-2005, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38642744

RESUMO

BACKGROUND: The causal nature of gut microbiota and cerebral small vessel disease (CSVD) is still obscure regardless of evidence supporting their observational correlations. OBJECTIVES: The primary objective of this research is to investigate the potentially pathogenic or protective causal impacts of specific gut microbiota on various neuroimaging subtypes of CSVD. METHODS: We obtained the latest summary-level genome-wide databases for gut microbiota and 9 CSVD traits. The univariable and multivariable Mendelian randomization (MR) studies were conducted to examine the possible causal link between exposure and outcome. Meanwhile, we conducted sensitivity analyses sequentially, containing the heterogeneity, pleiotropy, and leave-one-out analysis. Additionally, to clarify the potential bidirectional causality, the causality from CSVD traits to the identified gut microbiota was implemented through reverse MR analysis. RESULTS: The univariable MR analysis identified 22 genetically predicted bacterial abundances that were correlated with CSVD traits. Although conditioning on macronutrient dietary compositions, 2 suggestive relationships were retained using the multivariable MR analysis. Specifically, the class Negativicutes and order Selenomonadales exhibited a negative causal association with strictly lobar cerebral microbleeds, one neuroimaging trait of CSVD. There is insufficient evidence indicating the presence of heterogeneity and horizontal pleiotropy. Furthermore, the identified causal relationship was not driven by any single nucleotide polymorphism. The results of the reverse MR analysis did not reveal any statistically significant causality from CSVD traits to the identified gut microbiota. CONCLUSIONS: Our study indicated several suggestive causal effects from gut microbiota to different neuroimaging subtypes of CSVD. These findings provided a latent understanding of the pathogenesis of CSVD from the perspective of the gut-brain axis.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Microbioma Gastrointestinal , Análise da Randomização Mendeliana , Doenças de Pequenos Vasos Cerebrais/genética , Doenças de Pequenos Vasos Cerebrais/microbiologia , Humanos , Estudo de Associação Genômica Ampla
7.
J Surg Res ; 300: 439-447, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38865746

RESUMO

INTRODUCTION: Acute kidney injury (AKI) is a common complication after on-pump cardiac surgery, and previous studies have suggested that blood glucose is associated with postoperative AKI. However, limited evidence is available regarding intraoperative glycemic thresholds in cardiac surgery. The aim of this study was to explore the association between peak intraoperative blood glucose and postoperative AKI, and determine the cut-off values for intraoperative glucose concentration associated with an increased risk of AKI. METHODS: The study was retrospective and single-centered. Adult patients in West China Hospital of Sichuan University who underwent on-pump cardiac surgery (n = 3375) were included. The primary outcome was the incidence of AKI. Multivariable logistic analysis using restricted cubic spline was performed to explore the association between intraoperative blood glucose and postoperative AKI. RESULTS: The incidence of AKI in the study population was 18.0% (607 of 3375). Patients who developed AKI had a significantly higher peak intraoperative glucose during the surgery compared to those without AKI. After adjustment for confounders, the incidence of AKI increased with peak intraoperative blood glucose (adjusted odds ratio, 1.08, 95% confidence interval 1.03, 1.12). Furthermore, it was demonstrated that the possibility of AKI was relatively flat till 127.8 mg/dL (7.1 mmol/L) glucose levels which started to rapidly increase afterward. CONCLUSIONS: Increased intraoperative blood glucose was associated with an increased risk of AKI. Among patients undergoing on-pump cardiac surgery, avoiding a high glucose peak (i.e., below 127.8 mg/dL [7.1 mmol/L]) may reduce the risk of postoperative AKI.


Assuntos
Injúria Renal Aguda , Glicemia , Procedimentos Cirúrgicos Cardíacos , Complicações Pós-Operatórias , Humanos , Estudos Retrospectivos , Masculino , Feminino , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/sangue , Injúria Renal Aguda/diagnóstico , Pessoa de Meia-Idade , Glicemia/análise , Idoso , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/sangue , Incidência , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , China/epidemiologia , Fatores de Risco , Período Intraoperatório , Adulto
8.
Rapid Commun Mass Spectrom ; 38(8): e9722, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38419584

RESUMO

RATIONALE: Recently N-Fluoroarenesulfonamides (ArSO2 NHF) were found to be promising precursors for the preparation of N-fluorobenzenesulfonimide derivatives without applying F2 . However, very few studies have discussed the mass spectrometric behaviors of ArSO2 NHF with N-F structure. METHODS: In this article, we applied high-resolution electrospray ionization tandem mass spectrometry (HR-ESI-MS/MS) to study the effect on the mass spectrometric behaviors of ArSO2 NHF after the introduction of the F-atom to the N-atom of ArSO2 NH2 . RESULTS: High-resolution electrospray ionization mass spectrometry (HR-ESI-MS) experiments showed that ArSO2 NHF produced only good signals in negative ion mode, and the dominating product ion SO2 F- at m/z 83 was observed in all HR-ESI-MS/MS of ArSO2 NF- with different substituents in the Ar group. The formation of the product ion SO2 F- was proof of the gas-phase F-atom migration rearrangement from the N-atom to the S-atom in ESI-MS/MS of ArSO2 NF- . CONCLUSION: To fully explain the gas-phase reaction mechanism from ArSO2 NF- to SO2 F- , we studied the HR-ESI-MS/MS of deprotonated ArSO2 NHF and also performed theoretical calculations. Both results confirmed that ArSO2 NF- first underwent Smiles rearrangement to yield intermediate I (INT1) ArNFSO2 - , and then the F-atom of ArNFSO2 - migrated from the N-atom to the S-atom to form intermediate II (INT2) ArN- SO2 F, which finally dissociated to SO2 F- at m/z 83 with loss of a neutral nitrene (ArN). All these results showed that the formation of the product ion SO2 F- from ArSO2 NF- was a common and intrinsic gas-phase reactivity of ArSO2 NF- .

9.
Aging Male ; 27(1): 2339352, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38590113

RESUMO

OBJECTIVES: To evaluate the efficacy of a novel approach to achieve the optimal penile erection during the penile doppler ultrasound (PDU) examination, which was oral sildenafil combined alprostadil injection. MATERIALS AND METHODS: A total of 60 ED patients were enrolled in our prospective study, and they were randomly assigned to two group with different PDU order. The approaches assisted the PDU included two models, mode A meaning injection of 15 µg alprostadil and model B meaning oral sildenafil 100 mg plus injection of 15 µg alprostadil. The PDU parameters were measured continuously before induced erection, and 5, 10, 15, 20, 25 min. RESULTS: Each group included 30 ED patients with similar clinical characteristics. After pooling the results together, the PSV, EDV, and RI were all improved significantly, when adding the oral sildenafil administration to assist PDU. Also, the clinical response of oral sildenafil administration plus alprostadil injection was better than that in alprostadil injection alone (p = 0.016). The arterial ED were decreased from 31.67% to 15.00% with the P value 0.031, and the mixed ED was also decreased statistically (23.33% vs 8.33%, p = 0.024). CONCLUSION: Oral sildenafil administration plus alprostadil injection could improve the diagnostic accuracy of PDU.


Assuntos
Disfunção Erétil , Ereção Peniana , Masculino , Humanos , Citrato de Sildenafila/farmacologia , Ereção Peniana/fisiologia , Alprostadil , Disfunção Erétil/tratamento farmacológico , Disfunção Erétil/diagnóstico , Estudos Prospectivos , Pênis/diagnóstico por imagem , Ultrassonografia Doppler
10.
Oral Dis ; 30(2): 492-503, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36740958

RESUMO

OBJECTIVES: To explore the prognostic effects of previous cancer history on patients with major salivary gland cancer (SGC). SUBJECTS AND METHODS: SGC patients with (sec-SGC) and without (one-SGC) a previous cancer from the SEER database were identified. Cox proportional hazards regression (CoxPH) models were used to compare the prognosis between sec-SGC and one-SGC patients. Subgroup analyses for sec-SGC patients by gender, previous cancer types, previous cancer histology, and cancer diagnosis interval (CDI) were performed. Two CoxPH models were constructed to distinguish sec-SGC patients with different prognostic risks. RESULTS: 9098 SGC patients were enrolled. Overall, sec-SGC patients (adjusted HR [aHR] = 1.26, p < 0.001), especially those with a CDI ≤ 5 years (aHR = 1.47, p < 0.001), had worse overall survival (OS) than one-SGC patients. In subgroup analysis, only sec-SGC patients with a previous head and neck cancer who were female (aHR = 2.38, p = 0.005), with a CDI ≤ 5 years (aHR = 1.65, p = 0.007) or with a previous squamous cell carcinoma (aHR = 6.52, p < 0.001) had worse OS. Our models successfully differentiated all sec-SGC patients into high-, intermediate- and low-risk groups with different prognosis. CONCLUSIONS: Sec-SGC patients with different previous cancer types, gender, CDI and previous cancer histology had varied prognosis. The models we constructed could help differentiate the prognosis of sec-SGC patients with different risks.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias das Glândulas Salivares , Humanos , Feminino , Masculino , Prognóstico , Neoplasias das Glândulas Salivares/patologia , Carcinoma de Células Escamosas/patologia
11.
J Ultrasound Med ; 43(2): 397-403, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37948532

RESUMO

OBJECTIVES: The present study aims to explore the role of shear wave elastography (SWE) in the diagnosis of Peyronie disease (PD). METHODS: A total of 59 PD patients and 59 age-matched healthy adult men were included in this study. The B-mode ultrasound (US) and SWE were performed for all subjects, and the Young modulus (YM) values of the corresponding regions of the penis in the PD and control groups were recorded and compared. RESULTS: The mean age of the included PD patients and age-matched controls was 53.81 years (SD 9.52, range 32-73). On B-mode US evaluation, 41 (69.5%) of 59 included PD patients were found to have penile plaques, and the remaining 18 (30.5%) patients had no evidence of penile plaque. After evaluation using SWE, the YM values in the penile plaque region of these 41 patients with penile dysplasia were found to be significantly higher (60.29 kPa ± 19.95) than those outside the plaque (in the same patient) (21.05 kPa ± 4.58) and in the same penile region of the control group (20.59 kPa ± 4.65) (P < .001). In the remaining 18 PD patients, the results showed that the YM value of the abnormal penile region in the PD patients (56.67 kPa ± 13.52) was significantly higher than the YM value outside the abnormal penile region in the same patients (22.79 kPa ± 4.31) and in the same penile region in the control group (19.87 kPa ± 3.48) (P < .001; P < .001). CONCLUSIONS: In conclusion, this study showed that SWE as a non-invasive technique is useful in identifying and differentiating penile plaques in PD patients and is a simple, rapid and complementary method to B-mode US.


Assuntos
Técnicas de Imagem por Elasticidade , Induração Peniana , Placa Aterosclerótica , Masculino , Adulto , Humanos , Pessoa de Meia-Idade , Técnicas de Imagem por Elasticidade/métodos , Induração Peniana/diagnóstico por imagem , Ultrassonografia , Módulo de Elasticidade , Interpretação de Imagem Assistida por Computador/métodos
12.
Angew Chem Int Ed Engl ; 63(25): e202406324, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38637292

RESUMO

The reaction regioselectivity of gem-difluoroalkenes is dependent on the intrinsic polarity. Thus, the reversal of the regioselectivity of the addition reaction of gem-difluoroalkenes remains a formidable challenge. Herein, we described an unprecedented reversal of regioselectivity of hydrogen atom transfer (HAT) to gem-difluoroalkenes triggered by Fe-H species for the formation of difluoroalkyl radicals. Hydrogenation of the in situ generated radicals gave difluoromethylated products. Mechanism experiments and theoretical studies revealed that the kinetic effect of the irreversible HAT process resulted in the reversal of the regioselectivity of this scenario, leading to the formation of a less stable α-difluoroalkyl radical regioisomer. On basis of this new reaction of gem-difluoroalkene, the iron-promoted hydrohalogenation of gem-difluoroalkenes for the efficient synthesis of aliphatic chlorodifluoromethyl-, bromodifluoromethyl- and iododifluoromethyl-containing compounds was developed. Particularly, this novel hydrohalogenation of gem-difluoroalkenes provided an effect and large-scale access to various iododifluoromethylated compounds of high value for synthetic application.

13.
Angew Chem Int Ed Engl ; 63(11): e202318545, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38247345

RESUMO

Afterglow imaging holds great promise for ultrasensitive bioimaging due to its elimination of autofluorescence. Self-sustaining afterglow molecules (SAMs), which enable all-in-one photon sensitization, chemical defect formation and afterglow generation, possess a simplified, reproducible, and efficient superiority over commonly used multi-component systems. However, there is a lack of SAMs, particularly those with much brighter near-infrared (NIR) emission and structural flexibility for building high-contrast activatable imaging probes. To address these issues, this study for the first time reports a methylene blue derivative-based self-sustaining afterglow agent (SAN-M) with brighter NIR afterglow chemiluminescence peaking at 710 nm. By leveraging the structural flexibility and tunability, an activatable nanoprobe (SAN-MO) is customized for simultaneously activatable fluoro-photoacoustic and afterglow imaging of peroxynitrite (ONOO- ), notably with a superior activation ratio of 4523 in the afterglow mode, which is at least an order of magnitude higher than other reported activatable afterglow systems. By virtue of the elimination of autofluorescence and ultrahigh activation contrast, SAN-MO enables early monitoring of the LPS-induced acute inflammatory response within 30 min upon LPS stimulation and precise image-guided resection of tiny metastatic tumors, which is unattainable for fluorescence imaging.


Assuntos
Lipopolissacarídeos , Nanopartículas , Luminescência , Imagem Óptica , Nanopartículas/química
14.
Plant Physiol ; 190(1): 576-591, 2022 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-35640121

RESUMO

Plant mitochondrial fatty acid synthesis (mtFAS) appears to be important in photorespiration based on the reverse genetics research from Arabidopsis (Arabidopsis thaliana) in recent years, but its roles in plant development have not been completely explored. Here, we identified a tomato (Solanum lycopersicum) mutant, fern-like, which displays pleiotropic phenotypes including dwarfism, yellowing, curly leaves, and increased axillary buds. Positional cloning and genetic and heterozygous complementation tests revealed that the underlying gene FERN encodes a 3-hydroxyl-ACP dehydratase enzyme involved in mtFAS. FERN was causally involved in tomato morphogenesis by affecting photorespiration, energy supply, and the homeostasis of reactive oxygen species. Based on lipidome data, FERN and the mtFAS pathway may modulate tomato development by influencing mitochondrial membrane lipid composition and other lipid metabolic pathways. These findings provide important insights into the roles and importance of mtFAS in tomato development.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Solanum lycopersicum , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Ácidos Graxos/metabolismo , Regulação da Expressão Gênica de Plantas , Lipídeos , Solanum lycopersicum/metabolismo , Proteínas de Plantas/metabolismo
15.
Phys Rev Lett ; 131(1): 016201, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37478456

RESUMO

In twisted h-BN/graphene heterostructures, the complex electronic properties of the fast-traveling electron gas in graphene are usually considered to be fully revealed. However, the randomly twisted heterostructures may also have unexpected transition behaviors, which may influence the device performance. Here, we study the twist-angle-dependent coupling effects of h-BN/graphene heterostructures using monochromatic electron energy loss spectroscopy. We find that the moiré potentials alter the band structure of graphene, resulting in a redshift of the intralayer transition at the M point, which becomes more pronounced up to 0.22 eV with increasing twist angle. Furthermore, the twisting of the Brillouin zone of h-BN relative to the graphene M point leads to tunable vertical transition energies in the range of 5.1-5.6 eV. Our findings indicate that twist-coupling effects of van der Waals heterostructures should be carefully considered in device fabrications, and the continuously tunable interband transitions through the twist angle can serve as a new degree of freedom to design optoelectrical devices.

16.
Acta Pharmacol Sin ; 44(1): 157-168, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35655095

RESUMO

Hepatic steatosis plays a detrimental role in the onset and progression of alcohol-associated liver disease (ALD). Mesencephalic astrocyte-derived neurotrophic factor (MANF) is an evolutionarily conserved protein related to the unfolded protein response. Recent studies have demonstrated that MANF plays an important role in liver diseases. In this study, we investigated the role of MANF in ethanol-induced steatosis and the underlying mechanisms. We showed that the hepatic MANF expression was markedly upregulated in mouse model of ALD by chronic-plus-single-binge ethanol feeding. Moreover, after chronic-plus-binge ethanol feeding, hepatocyte-specific MANF knockout (HKO) mice displayed more severe hepatic steatosis and liver injury than wild-type (WT) control mice. Immunoprecipitation-coupled MS proteomic analysis revealed that arginosuccinate synthase 1 (ASS1), a rate-limiting enzyme in the urea cycle, resided in the same immunoprecipitated complex with MANF. Hepatocyte-specific MANF knockout led to decreased ASS1 activity, whereas overexpression of MANF contributed to enhanced ASS1 activity in vitro. In addition, HKO mice displayed unique urea cycle metabolite patterns in the liver with elevated ammonia accumulation after ethanol feeding. ASS1 is known to activate AMPK by generating an intracellular pool of AMP from the urea cycle. We also found that MANF supplementation significantly ameliorated ethanol-induced steatosis in vivo and in vitro by activating the AMPK signaling pathway, which was partly ASS1 dependent. This study demonstrates a new mechanism in which MANF acts as a key molecule in maintaining hepatic lipid homeostasis by enhancing ASS1 activity and uncovers an interesting link between lipid metabolism and the hepatic urea cycle under excessive alcohol exposure.


Assuntos
Fígado Gorduroso , Hepatopatias Alcoólicas , Animais , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Astrócitos/metabolismo , Etanol/toxicidade , Fígado Gorduroso/induzido quimicamente , Hepatócitos/metabolismo , Fígado/metabolismo , Camundongos Knockout , Fatores de Crescimento Neural/metabolismo , Proteômica , Ureia/metabolismo
17.
Environ Res ; 229: 115896, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37054832

RESUMO

Traffic noise, characterized by its highly fluctuating nature, is the second biggest environmental problem in the world. Highly dynamic noise maps are indispensable for managing traffic noise pollution, but two key difficulties exist in generating these maps: the lack of large amounts of fine-scale noise monitoring data and the ability to predict noise levels in the absence of noise monitoring data. This study proposed a new noise monitoring method, the Rotating Mobile Monitoring method, that combines the advantages of stationary and mobile monitoring methods and expands the spatial extent and temporal resolution of noise data. A monitoring campaign was conducted in the Haidian District of Beijing, covering 54.79 km of roads and a total area of 22.15 km2, and gathered 18,213 A-weighted equivalent noise (LAeq) measurements at 1-s intervals from 152 stationary sampling sites. Additionally, street view images, meteorological data and built environment data were collected from all roads and stationary sites. Using computer vision and GIS analysis tools, 49 predictor variables were measured in four categories, including microscopic traffic composition, street form, land use and meteorology. Six machine learning models and linear regression models were trained to predict LAeq, with random forest performing the best (R2 = 0.72, RMSE = 3.28 dB), followed by K-nearest neighbors regression (R2 = 0.66, RMSE = 3.43 dB). The optimal random forest model identified distance to the major road, tree view index, and the maximum field of view index of cars in the last 3 s as the top three contributors. Finally, the model was applied to generate a 9-day traffic noise map of the study area at both the point and street levels. The study is easily replicable and can be extended to a larger spatial scale to obtain highly dynamic noise maps.


Assuntos
Monitoramento Ambiental , Ruído dos Transportes , Monitoramento Ambiental/métodos , Automóveis , Modelos Lineares , Aprendizado de Máquina
18.
Environ Res ; 238(Pt 2): 117267, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37776939

RESUMO

Few previous studies have investigated the impacts of coexposure to multiple urban environmental factors on the prognosis of acute myocardial infarction (AMI) events. This study aimed to evaluate the associations between the urban exposome and AMI recurrence. We used data from 88,509 AMI patients from a large cohort obtained from the Beijing Cardiovascular Disease Surveillance System between 2013 and 2019. Twenty-six types of urban exposures were assessed within 300-m, 500-m, and 1000-m buffers of patients' home addresses in the baseline and cumulative average levels. We used the Cox proportional hazard model along with the Elastic Net (ENET) algorithm to estimate the hazard ratios (HRs) of recurrent AMI per interquartile range increase in each selected urban exposure. The increased risk of AMI recurrence was significantly associated with lower urban function diversity in the 500-m buffer, longer distance to subway stations and higher PM2.5 for both baseline and cumulative average exposure. The cumulative averages of two urban factors, including the distance to parks, and the density of fruit and vegetable shops in the 1000-m buffer, were also identified as significant factors affecting the risk of AMI recurrence. These findings can help improve the urban design for promoting human cardiovascular health.


Assuntos
Expossoma , Infarto do Miocárdio , Humanos , Material Particulado/análise , Pequim , Infarto do Miocárdio/epidemiologia , China/epidemiologia , Sobreviventes
19.
Environ Res ; 217: 114847, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36402183

RESUMO

Microorganisms play critical ecological roles in the global biogeochemical cycles. However, extensive information on the microbial communities in Qinghai-Tibet Plateau (QTP), which is the highest plateau in the world, is still lacking, particularly in high elevation locations above 4500 m. Here, we performed a survey of th e soil and water microbial communities in Bamucuo Lake, Tibet, by using shotgun metagenomic methods. In the soil and water samples, we reconstructed 75 almost complete metagenomic assembly genomes, and 74 of the metagenomic assembly genomes from the water sample represented novel species. Proteobacteria and Actinobacteria were found to be the dominant bacterial phyla, while Euryarchaeota was the dominant archaeal phylum. The largest virus, Pandoravirus salinus, was found in the soil microbial community. We concluded that the microorganisms in Bamucuo Lake are most likely to fix carbon mainly through the 3-hydroxypropionic bi-cycle pathway. This study, for the first time, characterized the microbial community composition and metabolic capacity in QTP high-elevation locations with 4555 m, confirming that QTP is a vast and valuable resource pool, in which many microorganisms can be used to develop new bioactive substances and new antibiotics to which pathogenic microorganisms have not yet developed resistance.


Assuntos
Lagos , Microbiota , Tibet , Bactérias/genética , Bactérias/metabolismo , Microbiologia do Solo , Solo , Água
20.
Environ Health ; 22(1): 2, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36604680

RESUMO

BACKGROUND: With rapid urbanization, the urban environment, especially the neighborhood environment, has received increasing global attention. However, a comprehensive overview of the association between neighborhood risk factors and human health remains unclear due to the large number of neighborhood risk factor-human health outcome pairs. METHOD: On the basis of a whole year of panel discussions, we first obtained a list of 5 neighborhood domains, containing 33 uniformly defined neighborhood risk factors. We only focused on neighborhood infrastructure-related risk factors with the potential for spatial interventions through urban design tools. Subsequently, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic meta-review of 17 infrastructure-related risk factors of the 33 neighborhood risk factors (e.g., green and blue spaces, proximity to major roads, and proximity to landfills) was conducted using four databases, Web of Science, PubMed, OVID, and Cochrane Library, from January 2000 to May 2021, and corresponding evidence for non-communicable diseases (NCDs) was synthesized. The review quality was assessed according to the A MeaSurement Tool to Assess Systematic Reviews (AMSTAR) standard. RESULTS: Thirty-three moderate-and high-quality reviews were included in the analysis. Thirteen major NCD outcomes were found to be associated with neighborhood infrastructure-related risk factors. Green and blue spaces or walkability had protective effects on human health. In contrast, proximity to major roads, industry, and landfills posed serious threats to human health. Inconsistent results were obtained for four neighborhood risk factors: facilities for physical and leisure activities, accessibility to infrastructure providing unhealthy food, proximity to industry, and proximity to major roads. CONCLUSIONS: This meta-review presents a comprehensive overview of the effects of neighborhood infrastructure-related risk factors on NCDs. Findings on the risk factors with strong evidence can help improve healthy city guidelines and promote urban sustainability. In addition, the unknown or uncertain association between many neighborhood risk factors and certain types of NCDs requires further research.


Assuntos
Doenças não Transmissíveis , Humanos , Cidades , Nível de Saúde , Doenças não Transmissíveis/epidemiologia , Fatores de Risco , Crescimento Sustentável
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