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1.
Cell Rep ; 40(5): 111160, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35921835

RESUMO

Although COVID-19 vaccines have been developed, multiple pathogenic coronavirus species exist, urging on development of multispecies coronavirus vaccines. Here we develop prototype lipid nanoparticle (LNP)-mRNA vaccine candidates against SARS-CoV-2 Delta, SARS-CoV, and MERS-CoV, and we test how multiplexing LNP-mRNAs can induce effective immune responses in animal models. Triplex and duplex LNP-mRNA vaccinations induce antigen-specific antibody responses against SARS-CoV-2, SARS-CoV, and MERS-CoV. Single-cell RNA sequencing profiles the global systemic immune repertoires and respective transcriptome signatures of vaccinated animals, revealing a systemic increase in activated B cells and differential gene expression across major adaptive immune cells. Sequential vaccination shows potent antibody responses against all three species, significantly stronger than simultaneous vaccination in mixture. These data demonstrate the feasibility, antibody responses, and single-cell immune profiles of multispecies coronavirus vaccination. The direct comparison between simultaneous and sequential vaccination offers insights into optimization of vaccination schedules to provide broad and potent antibody immunity against three major pathogenic coronavirus species.


Assuntos
COVID-19 , Coronavírus da Síndrome Respiratória do Oriente Médio , Vacinas Virais , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Lipossomos , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Nanopartículas , RNA Mensageiro/genética , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética , Vacinação , Vacinas Sintéticas , Vacinas de mRNA
2.
Sci Total Environ ; : 157996, 2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-35964743

RESUMO

Nano zero-valent iron via green synthesis (g-nZVI) has great potential in removing toxic hexavalent Cr(VI) from industrial wastewater. Sulfate and phosphate in wastewater can influence the Cr(VI) remediation of g-nZVI. In this study, the Cr(VI) removal kinetics by different g-nZVI materials were investigated with the existence of sulfate and/or phosphate, and the corresponding mechanisms were first revealed using multiple characterizations, including X-ray absorption near-edge spectra (XANES) and X-ray photoelectron spectroscopy (XPS). The results showed that the dominant Cr(OH)3 initially formed on the surface of g-nZVI particles before Cr2O3 formation during the reaction of g-nZVI with Cr(VI). Sulfate in wastewater can promote the reduction from Cr(VI) to Cr(OH)3 by g-nZVI, because sulfate triggers the release of Fe(II) and tea polyphenols (from tea extracts) from the g-nZVI surface due to the corrosion of Fe0 core, which is in line with an obvious increase in pseudo-second-order rate constant (k2) and subtle change in Cr(VI) removal capacity (qe). However, phosphate impedes the g-nZVI corrosion and inhibits qe because of the inner-sphere complexation of phosphate onto g-nZVI decreasing the released Fe(II) for Cr2O3 production. When sulfate and phosphate coexisted in contaminated water, the inhibition effect of phosphate in Cr(VI) removal by g-nZVI was stronger than the promotion of sulfate. Accordingly, qe value of g-nZVI declined from 93.4 mg g-1 to 77.5 mg g-1 with the k2 remaining consistent as the molar ratio of phosphate/sulfate increased from 0.1 to 10 in water. This study provides new insights into applying g-nZVI in efficient Cr(VI) removal from contaminated water with enrichment of sulphates and phosphates.

3.
Asian J Surg ; 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35918226

RESUMO

Lymph node dissection is a vital part of surgical treatment for early-stage non-small cell lung cancer (NSCLC). Lobectomy with systematic lymph node dissection (SLND) still remains the gold standard surgical treatment for early-stage NSCLC patients. However, an increasing number of studies have demonstrated that lobe-specific lymph node dissection (L-SLND) can be used as an alternative therapy for SLND in carefully selected patients with early-stage NSCLC. However, there are no currently available evidences of review summarizing the role of L-SLDN in treating early-stage NSCLC. Therefore, we performed this literature review by summarizing the existing literatures on the lymph node drainage pattern, definition, scope and role of L-SLND in patients with early-stage NSCLC, aiming to provide evidence for the application of L-SLND in patients with early-stage NSCLC.

4.
Histochem Cell Biol ; 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35930054

RESUMO

The Ran-GTP/importin ß pathway has been implicated in a diverse array of mitotic functions in somatic mitosis; however, the possible meiotic roles of Ran-GTP/importin ß in mammalian oocyte meiosis are still not fully understood. In the present study, importazole (IPZ), a small molecule inhibitor of the interaction between Ran and importin ß was used to explore the potential meiotic roles of Ran-GTP/importin ß in porcine oocytes undergoing meiosis. After IPZ treatment, the extrusion rate of the first polar body (PB1) was significantly decreased, and a higher proportion of the oocytes were arrested at the germinal vesicle breakdown (GVBD) stage. Moreover, IPZ treatment led to severe defects in metaphase I (MI) spindle assembly and chromosome alignment during the germinal vesicle (GV)-to-MI stage, as well as failure of metaphase II (MII) spindle reassembly and homologous chromosome segregation during the MI-to-MII stage. Notably, IPZ treatment decreased TPX2 expression and abnormal subcellular localization. Furthermore, the expression levels of aurora kinase A (AURKA) and transforming acidic coiled-coil 3 (TACC3) were significantly reduced after IPZ treatment. Collectively, these data indicate that the interaction of Ran-GTP and importin ß is essential for proper spindle assembly and successful chromosome segregation during two consecutive meiotic divisions in porcine oocytes, and regulation of this complex might be related to its effect on the TPX2 signaling cascades.

5.
Surg Endosc ; 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35836034

RESUMO

BACKGROUND: The purpose of this study was to introduce an "eight-step modularized procedure (M-RET)" for trans-subxiphoid robotic extended thymectomy for patients with myasthenia gravis (MG). Its safety and feasibility were further verified in this study. MATERIALS AND METHODS: This retrospective study included 87 consecutive MG patients who underwent trans-subxiphoid robotic extended thymectomy at our institution between September 2016 and August 2021. According to different resection models, patients were divided into two groups: traditional trans-subxiphoid robotic extended thymectomy group (T-RET group) and eight-step modularized technique group (M-RET group). Baseline demographic characteristics and operation-related parameters were collected and compared between the two groups. RESULTS: There were 41 (47.1%) patients in the M-RET group and 46 (52.9%) patients in the T-RET group. The M-RET group resected a greater amount of mediastinal adipose tissues and required more dissection time (median and interquartile range: 135.0, 125.0 to 164.0 v. 120.0, 105.0 to 153.8, P = 0.006) compared with the T-RET group. There were no statistically significant differences in terms of the intraoperative blood loss, duration of chest drainage, length of hospital stay, and postoperative complications between the two groups. There was no mortality or conversion in each of the two groups and all patients recovered well upon discharge. CONCLUSION: The eight-step modularized technique of trans-subxiphoid robotic extended thymectomy was verified to be a safe, effective, radical procedure, which offers unique superiority over ectopic thymic tissue resection.

6.
Biol Reprod ; 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35774023

RESUMO

G protein-coupled estrogen receptor (GPER), a seven-transmembrane G protein-coupled receptor, mediates the rapid pre-genomic signaling actions of estrogen and derivatives thereof. The expression of GPER is extensive in mammal male reproductive system. However, the functional role of GPER in mouse sperm has not yet been well recognized. This study revealed that GPER was expressed at the acrosome and the mid-flagellum of the mouse sperm. The endogenous GPER ligand 17ß-estradiol and the selective GPER agonist G1 increased intracellular Ca2+ concentration ([Ca2+]i) in mouse sperm, which could be abolished by G15, an antagonist of GPER. In addition, the G1-stimulated Ca2+ response was attenuated by interference with the phospholipase C (PLC) signaling pathways or by blocking the cation sperm channel (CatSper). Chlortetracycline staining assay showed that the activation of GPER increased the incidence of acrosome-reacted sperm. Conclusively, GPER was located at the acrosome and mid-flagellum of the mouse sperm. Activation of GPER triggered the elevation of [Ca2+]i through PLC-dependent Ca2+ mobilization and CatSper-mediated Ca2+ influx, which promoted the acrosome reaction in mouse sperm.

8.
APMIS ; 130(9): 578-589, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35751523

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) is resistant to almost all ß-lactam antibiotics. Hence, new ways to control MRSA infection, such as antibacterial antibodies, need to be explored. α-hemolysin is the most important virulence factor widely expressed in S. aureus. This study aimed to develop a new fully human antibody against α-hemolysin of S. aureus and research its neutralizing effect. The single-chain antibody fragments (scFvs) against S. aureus were screened from a fully human scFv library using phage display technology. The selected scFvs had good binding affinities to α-hemolysin and S. aureus. The IgG-like scFv-Fc inserted into the pcDNA3.1 or pMH3 vector was expressed in HEK293F suspension cells to extend the half-life and restore Fc function. The size of purified scFv-Fc was about 55 kDa. The functions of expressed scFv-Fcs against α-hemolysin were validated. The cytotoxicity assays showed that scFv555-Fc had better protective effects on A549 cells than other scFv-Fcs. The results of anti-rabbit erythrocyte lysis and A549 cell apoptosis assay confirmed that scFv555-Fc had a significant neutralizing effect on α-hemolysin. The scFv555-Fc was used to construct the docking model of antigen-antibody complexes using Discovery Studio software. It predicted that the key binding sites of α-hemolysin were TYR28, LYS37, PHE39, ARG56, and LYS58, which might be the key toxic sites of α-hemolysin. A novel fully human scFv-Fc antibody neutralizing the α-hemolysin toxin of S. aureus was successfully developed. The findings might provide a new theoretical basis and treatment method for preventing MRSA infection.


Assuntos
Anticorpos Neutralizantes , Proteínas Hemolisinas , Staphylococcus aureus Resistente à Meticilina , Anticorpos de Cadeia Única , Células A549 , Anticorpos Neutralizantes/química , Proteínas Hemolisinas/antagonistas & inibidores , Humanos , Anticorpos de Cadeia Única/química , Infecções Estafilocócicas/prevenção & controle
9.
Foods ; 11(11)2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35681333

RESUMO

Polygonum perfoliatum L. has a long history of medicinal and edible applications. Studies have shown that it can significantly protect liver injury, but the mechanism is unclear. The purpose of this study was to explore the protective mechanism of P. perfoliatum on chronic alcoholic liver injury from the perspective of lipid metabolism. After 8 weeks of alcohol exposure in male Wister mice, the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) in serum were significantly increased, and the activities of alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) in liver were significantly decreased. Meanwhile, pathological changes of liver tissue in mice were observed by histopathology. Then, Ultra-High Performance Liquid Chromatography (UHPLC) QExactive Plus Mass Spectrometer lipidomics and matrix-assisted laser desorption/ionization time-of-flight/time -of-flight (MALDI-TOF/TOF) mass spectrometry imaging methods were established to analyze lipid metabolism in mice. Ten different lipids were identified by statistical analysis, including Fatty Acyls, Glycerophospholipids, Prenol lipids and Sphingomyelins. After intervention with P. perfoliatum extracts at different doses (25 to 100 mg/kg), levels of AST, ALT, ALP in serum, and activities of ADH and ALDH in liver were significantly corrected. The hepatic cord structure was clear, and the liver cells were closely arranged without other obvious abnormalities. Non-target lipidomics analysis showed that P. perfoliatum extract could regulate the metabolic disorders of the 10 different lipids caused by continuous alcohol exposure. Pathway analysis suggested that the mechanism of P. perfoliatum extract on chronic alcoholic liver injury may be related to the regulation of linoleic acid and α-linolenic acid.

10.
Nat Commun ; 13(1): 3250, 2022 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-35668119

RESUMO

The Omicron variant of SARS-CoV-2 recently swept the globe and showed high level of immune evasion. Here, we generate an Omicron-specific lipid nanoparticle (LNP) mRNA vaccine candidate, and test its activity in animals, both alone and as a heterologous booster to WT mRNA vaccine. Our Omicron-specific LNP-mRNA vaccine elicits strong antibody response in vaccination-naïve mice. Mice that received two-dose WT LNP-mRNA show a > 40-fold reduction in neutralization potency against Omicron than WT two weeks post boost, which further reduce to background level after 3 months. The WT or Omicron LNP-mRNA booster increases the waning antibody response of WT LNP-mRNA vaccinated mice against Omicron by 40 fold at two weeks post injection. Interestingly, the heterologous Omicron booster elicits neutralizing titers 10-20 fold higher than the homologous WT booster against Omicron variant, with comparable titers against Delta variant. All three types of vaccination, including Omicron alone, WT booster and Omicron booster, elicit broad binding antibody responses against SARS-CoV-2 WA-1, Beta, Delta variants and SARS-CoV. These data provide direct assessments of an Omicron-specific mRNA vaccination in vivo, both alone and as a heterologous booster to WT mRNA vaccine.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Lipossomos , Camundongos , Nanopartículas , RNA Mensageiro/genética , SARS-CoV-2/genética , Vacinação , Vacinas Sintéticas , Vacinas de mRNA
11.
Cell Rep Methods ; 2(7): 100252, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35757815

RESUMO

Efficient quantitative assays for measurement of viral replication and infectivity are indispensable for future endeavors to develop prophylactic or therapeutic antiviral drugs or vaccines against SARS-CoV-2. We developed a SARS-CoV-2 cell-cell transmission assay that provides a rapid and quantitative readout to assess SARS-CoV-2 spike hACE2 interaction in the absence of pseudotyped particles or live virus. We established two well-behaved stable cell lines, which demonstrated a remarkable correlation with standard cell-free viral pseudotyping for inhibition by convalescent sera, small-molecule drugs, and murine anti-spike monoclonal antibodies. The assay is rapid, reliable, and highly reproducible, without a requirement for any specialized research reagents or laboratory equipment and should be easy to adapt for use in most investigative and clinical settings. It can be effectively used or modified for high-throughput screening for compounds and biologics that interfere with virus-cell binding and entry to complement other neutralization assays currently in use.

12.
Cell Rep Med ; 3(5): 100634, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35561673

RESUMO

Lipid nanoparticle (LNP)-mRNA vaccines offer protection against COVID-19; however, multiple variant lineages caused widespread breakthrough infections. Here, we generate LNP-mRNAs specifically encoding wild-type (WT), B.1.351, and B.1.617 SARS-CoV-2 spikes, and systematically study their immune responses. All three LNP-mRNAs induced potent antibody and T cell responses in animal models; however, differences in neutralization activity have been observed between variants. All three vaccines offer potent protection against in vivo challenges of authentic viruses of WA-1, Beta, and Delta variants. Single-cell transcriptomics of WT- and variant-specific LNP-mRNA-vaccinated animals reveal a systematic landscape of immune cell populations and global gene expression. Variant-specific vaccination induces a systemic increase of reactive CD8 T cells and altered gene expression programs in B and T lymphocytes. BCR-seq and TCR-seq unveil repertoire diversity and clonal expansions in vaccinated animals. These data provide assessment of efficacy and direct systems immune profiling of variant-specific LNP-mRNA vaccination in vivo.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Neutralizantes , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Imunidade , Lipossomos , Nanopartículas , RNA Mensageiro/genética , Vacinação
14.
Theriogenology ; 187: 164-172, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35576634

RESUMO

The targeting protein for Xklp2 (TPX2) is a spindle assembly factor, that can stimulate microtubule formation and promote spindle completion during mitosis. However, the role of TPX2 in mammalian oocyte meiotic maturation is still not fully understood. This study was conducted to address the dynamic distribution and potential roles of TPX2 in microtubule nucleation during meiotic maturation in porcine oocytes by microinjecting specific siRNAs. Western blotting results revealed that the expression of TPX2 displayed a lower level from 0 to 22 h of culture, while its expression exhibited a higher level after 28 h of culture. Immunofluorescence staining demonstrated that TPX2 was distributed along the microtubules and enriched in the poles after meiotic spindle formation at the 28 and 44 h of culture. From immunoprecipitation, TPX2 can interact with the microtubule-associated proteins aurora kinase A (AURKA) and transforming acidic coiled-coil 3 (TACC3). Meanwhile, the dynamic changes in the expression and localization of AURKA and TACC3 were highly consistent with TPX2 during meiotic maturation. After knocking down TPX2 by siRNA injection, the proportion of oocytes with aberrant spindles and scattered cytoplasmic actin filaments was significantly increased. In addition, TPX2 depletion markedly downregulated the expression of AURKA and TACC3. Thus, these results suggested that TPX2 is essential for meiotic spindle formation in the porcine oocyte, and that this regulation is related to its effect on AURKA and TACC3 expression.


Assuntos
Aurora Quinase A , Fuso Acromático , Animais , Aurora Quinase A/genética , Aurora Quinase A/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Mamíferos , Meiose , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos , Oócitos/metabolismo , Fuso Acromático/genética , Fuso Acromático/metabolismo , Suínos
15.
Front Surg ; 9: 861739, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35402500

RESUMO

Giant cell tumor (GCT) of the bone is a rare benign, locally aggressive tumor that occurs in the epiphysis of long bones, especially the lower femur and the upper tibia. GCT of the bone of cranial origin is very rare, accounting for 1% of all GCT of the bone. We report the diagnosis, treatment, and immunohistochemistry of a rare case of intracranial GCT of the bone. We also review and summarize the imaging features, diagnostic markers, and current major treatment options for GCT of the bone. Our case and literature review emphasizes the importance of considering the full picture when making a diagnosis, rather than relying on imaging alone to make the diagnosis.

16.
Phys Chem Chem Phys ; 24(16): 9384-9393, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35383793

RESUMO

The emerging semiconductor boron arsenide (BAs) with high thermal conductivity has attracted much attention recently, due to its promising application to overcome the bottleneck of high-density heat generated in power electronics and optoelectronic devices. In this work, based on first-principles calculations, we find that cubic BAs possesses high intrinsic electron/hole mobilities and the ionized impurity scattering plays a more important role in carrier scattering, compared with other scattering processes. The mobilities can be significantly enhanced by 14.9% and 76.2% for electrons and holes, respectively, by strain engineering. The investigation of the optoelectronic properties of indirect semiconductor cubic BAs by considering the many-body excitonic effects reveals that the contribution from finite-momentum excitons to optical properties is larger for photon energy ranging from 2.25 eV to 3.50 eV, compared with that from zero-momentum excitons. Finally, we observe that the phonon-electron couplings to total lattice thermal conductivities are non-trivial at low temperatures. These findings provide new insight into the transport and optoelectronic properties of cubic BAs, which are beneficial for the acceleration of the application of this revolutionary thermal management material.

17.
Front Immunol ; 13: 842008, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35386711

RESUMO

To review the role of inflammation in the occurrence and development of benign prostatic hyperplasia (BPH), we searched PubMed for the latest published articles up to February 2021 using the following key words: "benign prostatic hyperplasia", "inflammation", "pathogenesis" and "disease development". Articles were obtained and reviewed to provide a systematic review of the current progress of the role of inflammation in the pathogenesis and progression of BPH. Inflammation contributes to the initiation and maintenance of unregulated cell proliferation and is closely related to the occurrence and development of BPH. Its action pathways include tissue damage and subsequent chronic healing, autoimmunity, and coaction with androgens. During the progression of inflammation, macrophages, interleukin-8 (IL-8), interleukin-1 (IL-1) and other inflammatory-related substances aggregate locally and cause BPH through various biochemical pathways. At the same time, BPH can also counteract inflammation to expand its scope and aggravate the situation. Inflammation can independently affect the development of BPH in a variety of ways, and it can also interact with androgens. In the course of treatment, early intervention in the occurrence and development of inflammation in prostate tissue can slow down the progression of BPH. The combination of standard therapies and anti-inflammatory measures may provide valuable new ideas for the treatment of BPH.


Assuntos
Hiperplasia Prostática , Envelhecimento , Androgênios/metabolismo , Anti-Inflamatórios , Humanos , Inflamação , Masculino
18.
Bull Environ Contam Toxicol ; 108(6): 1033-1038, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35426516

RESUMO

To evaluate combined effects of co-existed pesticides and nanomaterials on aquatic plants, the toxicity of herbicide atrazine (ATZ) on Iris pseudacorus in the presence and absence of Graphene oxide (GO) was investigated using chlorophyll a fluorescence transients. Results showed that GO reduced ATZ accumulation in plant. ATZ or ATZ combined with GO mainly blocked electron transport beyond QA at PSII as indicated by the sharp rise of the J-step level of fluorescence rise kinetics. The pronounced increase in Fm and the loss of I-step were observed when ATZ was at 2.0 mg·L- 1 implying the damage on the oxygen evolution complex and PSI. GO at environmentally relevant concentration did not exhibit significant photosynthetic inhibitory effects on I. pseudacorus. GO at 1.0 mg·L- 1 promoted photosynthesis of I. pseudacorus under ATZ stress at 2.0 mg·L- 1. These result indicated that the presence of GO alleviated the photosynthesis inhibition by ATZ at high levels.


Assuntos
Atrazina , Herbicidas , Iris (Planta) , Atrazina/toxicidade , Clorofila A , Grafite , Herbicidas/toxicidade , Fotossíntese , Plantas
19.
Membranes (Basel) ; 12(4)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35448387

RESUMO

The realistic resistance zone of water and salt molecules to transport across a TFC-RO membrane is the topmost polyamide nanofilm. The existence of hollow voids in the fully aromatic polyamide (PA) film gives its surface ridge-and-valley morphologies, which confuses the comprehensions of the definition of the PA thickness. The hollow voids, however, neither participate in salt-water separation nor hinder water penetrating. In this paper, the influence of intrinsic thickness (single wall thickness) of the PA layer on water permeability was studied by adjusting the concentration of reacting monomers. It confirms that the true permeation resistance of water molecules originates from the intrinsic thickness portion of the membrane. The experimental results show that the water permeability constant decreases from 3.15 ± 0.02 to 2.74 ± 0.10 L·m-2·h-1·bar-1 when the intrinsic thickness of the membrane increases by 9 nm. The defects on the film surface generate when the higher concentration of MPD is matched with the relatively low concentration of TMC. In addition, the role of MPD and TMC in the micro-structure of the PA membrane was discussed, which may provide a new way for the preparation of high permeability and high selectivity composite reverse osmosis membranes.

20.
Front Plant Sci ; 13: 816492, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35283889

RESUMO

The commodity value of fruits is directly affected by fruit flavor and color. Secondary metabolites, such as amino acids, organic acids, esters, and ß-carotene, are important synthetic products, which are of great significance in the flavor formation of mango fruits. In this study, a total of 309 different metabolites, consisting of organic acids, amino acids, phenolic acids, and saccharides, and a further 84 types of volatile organic compounds (VOCs) were identified in differential levels in TR vs. MG mango fruit stages. The major volatile compounds found were ester [2(3H)-furanone, 5-ethyldihydro; N-(2,5-ditrifluoromethylbenzoyl)-D-alanine, pentyl ester; and Octanoic acid, ethyl ester], aldehyde (benzaldehyde, 3-ethyl, and nonanal), and phenol [2-(1,1-dimethylethyl)-6-(1-methylethyl) phenol]. The analysis of carotenoid contents identified 68 carotenoids and we report for the first-time significant contents of zeaxanthin palmitate and (E/Z)-phytoene in mango fruits. α-carotene was a further major contributor to carotene contents with lesser contributions from 5,6epoxy-lutein-caprate-palmitate, ß-carotene, lutein oleate, and ß-cryptoxanthin. What is more, lutein content was significantly decreased in TR vs. MG fruit. RT-qPCR analysis revealed that relative to the MG stage, the expression of carotenogenic genes GGPS, PSY, LCYB, and ZEP was downregulated in TR mango fruit, whereas the transcript levels of PSD, CHYB, and NCED were downregulated. Additionally, the transcription level of some transcription factors (MYB, bHLH, and NAC) was highly correlated with pigment content in the pulp and may be responsible for carotenoid accumulation. The results describe major differences in metabolic pathways during the transition from MG to the TR stage of fruit ripening that are likely to contribute alterations in fruit flavor and provide several associated genes to be further studied in mango fruit.

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