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1.
Chem Commun (Camb) ; 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39363686

RESUMO

The efficient preparation of long-chain amines via a one-step transfer-hydrogenation/reductive-amination reaction (THRA) of polyenals has been achieved. This strategy, which combines transfer hydrogenation and reductive amination, significantly enhances the synthetic efficiency of amino compounds. Additionally, this protocol offers a practical method for carbon-chain elongation/amination to construct long-chain amino compounds. The reaction system exhibits remarkable versatility in substrate scope using a non-noble ruthenium catalyst with formate and isopropanol as hydrogen sources, making it an appealing method for drug synthesis and molecular modification.

2.
Sci Total Environ ; 954: 176377, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39299320

RESUMO

In dryland farming, plastic film mulching can significantly increase crop yields, but the resulting residues impair soil health. Heretofore, only few studies had examined how heat treatment facilitates the rapid degradation of polyethylene (PE) residual films. Herein, we characterized the variations in micro-morphology, functional groups, and crystallinity of PE residual films after moderate heat exposure using a self-made flame-spraying equipment. The results revealed that solid residues (SR) obtained from flame-spraying showed a gravimetric weight loss of 9.39 %-15.35 % compared with untreated PE residual films (UPF). Scanning electron microscope equipped with energy dispersive X-ray spectroscopy revealed considerable pits, cracks, and visible roughness in appearance and an increase in the oxygen-to-carbon (O/C) atomic ratio. Fourier-transform infrared spectroscopy identified characteristic oxygen-containing functional groups and double bonds. X-ray diffraction showed that flame-spraying treatments did not alter the crystal form of polymer, but increased the crystallinity. Higher flame-spraying temperatures resulted in larger oxygen-containing bond indices and lower crystallinity, suggesting a more severe decomposition of PE residual film. The possible volatile gaseous products at different reaction temperatures were predicted using thermogravimetric analysis coupled with Fourier transform infrared spectroscopy (TG-FTIR). Degradation of the PE residual film started at 220 °C, and concentrated release of major products such as long-chain aliphatic hydrocarbons, ketones, and CO2, occurred in the temperature range of 340 °C-440 °C. These results highlighted the effectiveness of the moderate flame-spraying method in accelerating rapid decomposition of residual films, and a flame-spraying temperature range of 220 °C-340 °C should be recommended to avoid potential environmental risks induced by the release of large quantities of degradation products. This study will contribute to enhance our understanding of the thermal oxidative degradation behavior of PE waste and provide a scientific basis for the rapid and clean establishment of PE residual films mitigation in agricultural fields.

3.
Plants (Basel) ; 13(18)2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39339586

RESUMO

Tillage practices significantly influence crop yield and soil quality. This study investigated the impact of rotary tillage (RT) and deep tillage (DT) on soil properties, microbial diversity, and melon (Cucumis melo L.) root growth and yield. RT involved breaking up the topsoil to a depth of 15 cm using a rotary tiller, while DT employed a rotary tiller followed by a moldboard plow to turn the soil layer over to a depth of 35 cm. The melon variety "Nasimi" was used as the material. Our findings revealed a remarkable response of soil phosphorus to tillage practices. High-throughput sequencing results revealed a significant impact of tillage practices on the soil fungal composition, richness, and diversity but little impact on the bacterial communities. Compared to RT, DT markedly enhanced melon root length, root surface area, root volume, and mean root diameter by 47.42%, 56.70%, 58.83%, and 27.28%, respectively. Additionally, DT treatments significantly increased melon yield (53.46%) compared to RT. The results indicate that DT improves soil nutrient availability, affects soil fungal community characteristics, and optimizes root distribution in soil, thereby improving melon yield. The findings offer valuable theoretical insights for the implementation of effective tillage practices in open-field melon cultivation.

4.
J Proteome Res ; 23(10): 4658-4673, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39298182

RESUMO

The dormancy of cancer stem cells is a major factor leading to drug resistance and a high rate of late recurrence and mortality in estrogen receptor-positive (ER+) breast cancer. Previously, we demonstrated that a stiffer matrix induces tumor cell dormancy and drug resistance, whereas a softened matrix promotes tumor cells to exhibit a stem cell state with high proliferation and migration. In this study, we present a comprehensive analysis of the proteome and phosphoproteome in response to gradient changes in matrix stiffness, elucidating the mechanisms behind cell dormancy-induced drug resistance. Overall, we found that antiapoptotic and membrane transport processes may be involved in the mechanical force-induced dormancy resistance of ER+ breast cancer cells. Our research provides new insights from a holistic proteomic and phosphoproteomic perspective, underscoring the significant role of mechanical forces stemming from the stiffness of the surrounding extracellular matrix as a critical regulatory factor in the tumor microenvironment.


Assuntos
Neoplasias da Mama , Matriz Extracelular , Células-Tronco Neoplásicas , Fosfoproteínas , Proteômica , Humanos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Matriz Extracelular/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Feminino , Proteômica/métodos , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Proteoma/análise , Proteoma/metabolismo , Microambiente Tumoral , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Células MCF-7
6.
Biochem Biophys Res Commun ; 739: 150568, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39178797

RESUMO

Doxorubicin (DOX), as a first-line anticancer drug, is widely used in the treatment of various cancers. However, its clinical application is restricted due to its severe cardiac toxicity. Previous studies have indicated exercise training can alleviate the DOX-induced cardiotoxicity (DIC), but the underlying mechanism remains unclear. Our research has discovered, post-exercise, an elevated expression level of mir-17-3p, but in DIC its level decreases. Therefore, we further studied the effect of exercise mir-17-3p axis on DIC. In vivo, we simulated DIC mouse model, followed by an intervention using swimming and adenovirus to inhibit mir-17-3p. We found that inhibition of mir-17-3p can weaken the protection of exercise against DIC, presenting as weakened heart function. Besides, the levels of Malondialdehyde and Fe2+ in the cardiac tissue increased, along with diminished glutathione peroxidase 4 and Solute Carrier Family 7 Member 11 levels, and a decline in the concentration of glutathione, causing an increase in ferroptosis. Moreover, in vitro, we used dual-luciferase assay to confirm that Kelch Like ECH Associated Protein 1 (KEAP1) can be a target gene of mir-17-3p. We used Keap1/NFE2 Like BZIP Transcription Factor 2 (NRF2) inhibitor brusatol and Stimulator of Interferon Response CGAMP Interactor 1 (STING) agonist SR-717 to verify the mir-17-3p/KEAP1 axis can affect the Cyclic GMP-AMP Synthase (CGAS)/STING pathway, leading to further ferroptosis in DIC. This manifested as a reduction in ferroptosis. In summary, our research suggests swimming training enhances the levels of mir-17-3p, thereby activating the KEAP1/NRF2 pathway, and weakening the CGAS/STING pathway, improving ferroptosis in DIC.

7.
iScience ; 27(9): 110602, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39211577

RESUMO

Clinical research indicates that SARS-CoV-2 infection is linked to several neurological consequences, and the virus is still spreading despite the availability of vaccinations and antiviral medications. To determine how hosts respond to SARS-CoV-2 infection, we employed LC-MS/MS to perform ubiquitinome and proteome analyses of the brain cortexes from K18-hACE2 mice in the presence and absence of SARS-CoV-2 infection. A total of 8,024 quantifiable proteins and 5,220 quantifiable lysine ubiquitination (Kub) sites in 2023 proteins were found. Glutamatergic synapse, calcium signaling pathway, and long-term potentiation may all play roles in the neurological consequences of SARS-CoV-2 infection. Then, we observed possible interactions between 26 SARS-CoV-2 proteins/E3 ubiquitin-protein ligases/deubiquitinases and several differentially expressed mouse proteins or Kub sites. We present the first description of the brain cortex ubiquitinome in K18-hACE2 mice, laying the groundwork for further investigation into the pathogenic processes and treatment options for neurological dysfunction following SARS-CoV-2 infection.

8.
Syst Rev ; 13(1): 189, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030630

RESUMO

BACKGROUND: The COVID-19 pandemic has caused a large mortality and morbidity burden globally. For individuals, a strong immune response is the most effective means to block SARS-CoV-2 infection. To inform clinical case management of COVID-19, development of improved vaccines, and public health policy, a better understanding of antibody response dynamics and duration following SARS-CoV-2 infection and after vaccination is imperatively needed. METHODS: We systematically analyzed antibody response rates in naturally infected COVID-19 patients and vaccinated individuals. Specifically, we searched all published and pre-published literature between 1 December 2019 and 31 July 2023 using MeSH terms and "all field" terms comprising "COVID-19" or "SARS-CoV-2," and "antibody response" or "immunity response" or "humoral immune." We included experimental and observational studies that provided antibody positivity rates following natural COVID-19 infection or vaccination. A total of 44 studies reporting antibody positivity rate changes over time were included. RESULTS: The meta-analysis showed that within the first week after COVID-19 symptom onset/diagnosis or vaccination, antibody response rates in vaccinated individuals were lower than those in infected patients (p < 0.01), but no significant difference was observed from the second week to the sixth month. IgG, IgA, and IgM positivity rates increased during the first 3 weeks; thereafter, IgG positivity rates were maintained at a relatively high level, while the IgM seroconversion rate dropped. CONCLUSIONS: Antibody production following vaccination might not occur as quickly or strongly as after natural infection, and the IgM antibody response was less persistent than the IgG response.


Assuntos
Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Vacinação , Humanos , COVID-19/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , SARS-CoV-2/imunologia , Imunidade Inata/imunologia , Formação de Anticorpos/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia
9.
PLOS Glob Public Health ; 4(7): e0003387, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38990924

RESUMO

Understanding public preferences concerning vaccination is critical to inform pandemic response strategies. To investigate Chinese adults' preferences regarding COVID-19 vaccine attributes, we conducted a cross-sectional online survey in 12,000 Chinese adults in June-July, 2021. Participants were requested to answer a series of discrete choice questions related to hypothetical COVID-19 vaccines. Using mixed logit models, our analysis revealed that participants had a higher preference for COVID-19 vaccines with longer duration of protection (coefficient: 1.272, 95% confidence interval [1.016 to 1.529]) and higher efficacy (coefficient: 1.063, [0.840, 1.287]). Conversely, participants demonstrated a lower preference associated with higher risk of rare but serious side-effects (coefficient: -1.158, [-1.359, -0.958]), oral administration (coefficient: -0.211, [-0.377, -0.046]), more doses (coefficient: -0.148, [-0.296, 0.000]) and imported origin (coefficient: -0.653, [-0.864, -0.443]). Moreover, preferences were heterogeneous by individual factors: highly educated participants were more sensitive to the negative vaccine attributes including price (coefficient -0.312, [-0.370, -0.253]) and imported vaccine (coefficient -0.941, [-1.186, -0.697]); there was also substantial heterogeneity in vaccine preferences with respect to age group, marital status, work status, income, chronic diagnosis history, COVID-19 vaccination history and geographic regions. As the first study of examining the public preferences for COVID-19 vaccine in China with a large nationwide sample of 12,000 adults, our results indicate that future vaccine should pose lower risk, possess longer protection period, have higher efficacy, be domestically produced, and have lower costs to increase the COVID-19 vaccination coverage. Our current study findings from this study provide insights and recommendations for not only COVID-19 vaccine design but also vaccine attribute preferences to increase vaccine uptake in potential future pandemics.

10.
BMC Musculoskelet Disord ; 25(1): 509, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38956545

RESUMO

BACKGROUND: The lumbar vertebra and paraspinal muscles play an important role in maintaining the stability of the lumbar spine. Therefore, the aim of this study was to investigate the relationship between paraspinal muscles fat infiltration and vertebral body related changes [vertebral bone quality (VBQ) score and Modic changes (MCs)] in patients with chronic low back pain (CLBP). METHODS: Patients with CLBP were prospectively collected in four hospitals and all patients underwent 3.0T magnetic resonance scanning. Basic clinical information was collected, including age, sex, course of disease (COD), and body mass index (BMI). MCs were divided into 3 types based on their signal intensity on T1 and T2-weighted imaging. VBQ was obtained by midsagittal T1-weighted imaging (T1WI) and calculated using the formula: SIL1-4/SICSF. The Proton density fat fraction (PDFF) values and cross-sectional area (CSA) of paraspinal muscles were measured on the fat fraction map from the iterative decomposition of water and fat with the echo asymmetry and least-squares estimation quantitation (IDEAL-IQ) sequences and in/out phase images at the central level of the L4/5 and L5/S1 discs. RESULTS: This study included 476 patients with CLBP, including 189 males and 287 females. 69% had no Modic changes and 31% had Modic changes. There was no difference in CSA and PDFF for multifidus(MF) and erector spinae (ES) at both levels between Modic type I and type II, all P values>0.05. Spearman correlation analysis showed that VBQ was weakly negatively correlated with paraspinal muscles CSA (all r values < 0.3 and all p values < 0.05), moderately positive correlation with PDFF of MF at L4/5 level (r values = 0.304, p values<0.001) and weakly positively correlated with PDFF of other muscles (all r values<0.3 and all p values<0.001). Multivariate linear regression analysis showed that age (ß = 0.141, p < 0.001), gender (ß = 4.285, p < 0.001) and VBQ (ß = 1.310, p = 0.001) were related to the total PDFF of muscles. For MCs, binary logistic regression showed that the odds ratio values of age, BMI and COD were 1.092, 1.082 and 1.004, respectively (all p values < 0.05). CONCLUSIONS: PDFF of paraspinal muscles was not associated with Modic classification. In addition to age and gender, PDFF of paraspinal muscles is also affected by VBQ. Age and BMI are considered risk factors for the MCs in CLBP patients.


Assuntos
Tecido Adiposo , Dor Lombar , Vértebras Lombares , Músculos Paraespinais , Humanos , Feminino , Masculino , Músculos Paraespinais/diagnóstico por imagem , Músculos Paraespinais/patologia , Dor Lombar/diagnóstico por imagem , Estudos Prospectivos , Estudos Transversais , Pessoa de Meia-Idade , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Adulto , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/patologia , Idoso , Imageamento por Ressonância Magnética , Dor Crônica/diagnóstico por imagem
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