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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 284: 121832, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36088741

RESUMO

Total antioxidant capacity (TAC) is an important indicator for evaluating oxidative stress of the human body. Since TAC is related to the concentration of reducing substances, it can be detected by using peroxidase-like or oxidase-like activity of nanozyme materials. In this work, the cobalt and nitrogen co-doped carbon dots (Co/N-CDs) are fabricated for building stability and high peroxidase-like nanozyme through the Box-Behnken design of response surface methodology. The morphology and luminescence properties of obtained Co/N-CDs were characterized by TEM and fluorophotometer, respectively. Interestingly, the surface charge of Co/N-CDs are innovatively investigated by a simple and widespread gel electrophoresis, which holds the potential to be an alternative to Zeta potential analysis. In addition, a flow injection spectrophotometric assay to detect ascorbic acid is develop with a high sensitivity and automation based on a Co/N-CDs/guaiacol/H2O2 catalytic reaction system. The proposed method is also responsive to other reducing substances such as cysteine and glutathione. Therefore, the presented sensor can realize the determination of TAC, and then, some actual human serum samples are detected accurately and quickly (the recovery rates are 93.46-105.61 %).


Assuntos
Carbono , Pontos Quânticos , Antioxidantes/análise , Ácido Ascórbico , Cobalto , Cisteína/análise , Glutationa , Guaiacol , Humanos , Peróxido de Hidrogênio/análise , Nitrogênio , Peroxidase , Peroxidases
2.
J Colloid Interface Sci ; 630(Pt A): 772-782, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36283265

RESUMO

Immobilizing catalyst system faces the challenge of balancing catalysts stability and exposure of active site in water treatment. In this study, a novel in-situ synthesis of monoclinic phase of titanium dioxide (TiO2(B)) in cellulose-derived carbon aerogel (TCA) is proposed for processing multi-task in water treatment. The homogeneous gelation reaction supported the high dispersion of TiO2(B) in carbon skeleton. Meanwhile, TiO2 acts as crosslinker to reinforce cellulose network, then the grain refinement of amorphous TiO2 is limited to obtain TiO2(B) during carbonization. Benefiting from the reinforced structure, TCA remains the porous structure after carbonization and exposes more adsorption site than carbon aerogel blended with anatase particles (ACA). The adsorption performance of TCA are 837.3 mg/g, 1156.2 mg/g and 512.6 mg/g on methylene blue, malachite green and crystal violet, respectively. Compared with ACA, the superior interaction between TiO2 and graphite-like carbon improves the degradation rate of tetracycline from 1.3 × 10-3 min-1 to 8.6 × 10-3 min-1, and maintains the degradation efficiency in 3 rounds cyclic test. Besides, TCA also exhibits nearly twice to ACA on absorption capacity of different oil. This facile in-situ synthesis method offers a new insight in fabricating carbon aerogel immobilized photocatalysts system for multi-task in water treatment.


Assuntos
Nanocompostos , Purificação da Água , Carbono , Titânio/química , Nanocompostos/química , Celulose/química , Catálise
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 286: 122025, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36308829

RESUMO

In this paper, highly fluorescent carbon dots were synthesized from sodium ascorbate and polyethyleneimine at room temperature (R-CDs). The proposed green synthesis method was energy-saving, environmentally friendly and easy online. R-CDs exhibit an optimal emission peak of 490 nm under excitation at 380 nm with a quantum yield of 32 %. R-CDs morphology, composition, and properties were characterized using TEM, FTIR, XPS, UV-vis and fluorescence spectroscopy. The study revealed that nitrite quenched the fluorescence of R-CDs under acidic conditions. Subsequently, this discovered reaction of R-CDs and nitrite was combined with flow-injection technology, and a simple, precise and automatic fluorescence strategy for nitrite determination was accomplished. The response to nitrite was linear in 5-300 µg·L-1 concentration range and the limit of detection was 2.85 µg·L-1 (3.3 S/k). This method was applied to nitrite determination in Sichuan pickles during the pickling process and results were consistent with the standard method, demonstrating its feasibility in practical applications.


Assuntos
Alimentos Fermentados , Pontos Quânticos , Carbono/química , Nitritos , Pontos Quânticos/química , Temperatura , Espectrometria de Fluorescência , Corantes Fluorescentes/química
4.
JACC Basic Transl Sci ; 7(10): 1021-1037, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36337919

RESUMO

Modulation of sarcomere contractility represents a new therapeutic opportunity for the treatment of heart failure by directly targeting the thick and thin filament proteins of the sarcomere to increase cardiac muscle contraction. This study compared the effect of 2 small molecules (M and T) that selectively alter myosin thick filament (M) or troponin thin filament (T) activity on overall cardiac muscle mechanics. This study revealed key differences related to the mechanism utilized by M and T to increase contractile force generation and suggests that targeting different proteins within the sarcomere may result in differentiating therapeutic profiles.

5.
Curr Issues Mol Biol ; 44(11): 5788-5801, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36421677

RESUMO

Metabolic dysregulation of the retinal pigment epithelium (RPE) has been implicated in age-related macular degeneration (AMD). However, the molecular regulation of RPE metabolism remains unclear. RIP140 is known to affect oxidative metabolism and mitochondrial biogenesis by negatively controlling mitochondrial pathways regulated by PPAR-γ co-activator-1 α(PGC-1α). This study aims to disclose the effect of RIP140 on the RPE metabolic program in vitro and in vivo. RIP140 protein levels were assayed by Western blotting. Gene expression was tested using quantitative real-time PCR (qRT-PCR), ATP production, and glycogen concentration assays, and the release of inflammatory factors was analyzed by commercial kits. Mice photoreceptor function was measured by electroretinography (ERG). In ARPE-19 cells, RIP140 overexpression changed the expression of the key metabolic genes and lipid processing genes, inhibited mitochondrial ATP production, and enhanced glycogenesis. Moreover, RIP140 overexpression promoted the translocation of NF-κB and increased the expression and production of IL-1ß, IL-6, and TNF-α in ARPE-19 cells. Importantly, we also observed the overexpression of RIP140 through adenovirus delivery in rat retinal cells, which significantly decreased the amplitude of the a-wave and b-wave measured by ERG assay. Therapeutic strategies that modulate the activity of RIP140 could have clinical utility for the treatment of AMD in terms of preventing RPE degeneration.

6.
Front Public Health ; 10: 996447, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36353286

RESUMO

Background: Malnutrition, dynapenia, and sarcopenia are prevalent conditions among patients with maintenance hemodialysis (MHD). They are related to numerous adverse health outcomes. The aim of this study was to compare the effect of three nutritional screening tools on predicting the risk of dynapenia and sarcopenia in patients with MHD. Methods: From July 2020 to April 2021, a total of 849 patients with MHD were enrolled at seven different healthcare facilities in Shanghai, China in this multi-center cross-sectional study. Geriatric nutritional risk index (GNRI), malnutrition inflammation score (MIS), and creatinine (Cr) index were used for nutritional assessment. The cutoff values of muscle mass and strength to define dynapenia, pre-sarcopenia, and sarcopenia were based on the consensus by the Asia Working Group of Sarcopenia in 2019. Results: Among 849, almost 60% were malnourished with the majority suffering from dynapenia (27.7%), followed by sarcopenia (22.7%), and pre-sarcopenia (6.2%).The area under the receiver-operating characteristic curve for GNRI was 0.722 [95% confidence interval (CI) = 0.684-0.760] and 0.723 (95% CI = 0.663-0.783) in predicting sarcopenia and pre-sarcopenia. The GNRI [odds ratio (OR) =6.28, 95% CI: 4.05-9.73], MIS (OR =1.91, 95% CI: 1.31-2.78), and the Cr index (OR =2.73, 95% CI: 1.71-4.34) were all significantly associated with the risk of sarcopenia. More importantly, the sarcopenia predictability of the GNRI appears greater than the MIS and Cr index, while MIS was similar to the Cr index. Similarly, the superiority of GNRI prediction was also found in pre-sarcopenia, but not in dynapenia. Conclusion: All the three nutritional screening tools were significantly associated with an increased risk of sarcopenia. The sarcopenia predictability of the GNRI was greater than the MIS and Cr index.


Assuntos
Desnutrição , Sarcopenia , Humanos , Idoso , Avaliação Nutricional , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia , Sarcopenia/complicações , Estado Nutricional , Estudos Transversais , Avaliação Geriátrica , China , Diálise Renal/efeitos adversos , Desnutrição/diagnóstico , Desnutrição/epidemiologia , Desnutrição/etiologia , Creatinina
7.
Artigo em Chinês | MEDLINE | ID: mdl-36373640

RESUMO

Each stage of chronic kidney disease has a high risk of cognitive dysfunction.The decline of cognitive function will affect the daily life and treatment compliance of the patients with chronic kidney disease and increase the patients' risk of death and public health burden,which has aroused widespread concern.However,the specific mechanism of cognitive impairment in the patients with chronic kidney disease remains unclear.This paper summarizes the possible association mechanisms,related indicators,and impaired cognitive domains,aiming to provide a theoretical basis for the early diagnosis and slow down the progression of the cognitive impairment associated with chronic kidney disease.

8.
Int Rev Immunol ; : 1-12, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36369864

RESUMO

Preeclampsia (PE), a leading cause of maternal and fetal morbidity and mortality, is closely related to the immune system alterations. However, little is known about the landscape and heterogeneity of maternal immune system at single-cell level among PE patients. In this study, peripheral blood mononuclear cells (PBMCs) were isolated from three early-onset preeclamptic pregnant women and two healthy control, respectively. Single-cell RNA sequencing was performed on 10× genomics platform and single-cell transcriptomes were obtained to characterize immune cell subgroups at the pregnant and postpartum stages. In total, 80,429 single-cell transcriptomes were obtained. 19 cellular compositions were identified, which were categorized into six cell types including T cells, natural killer (NK) cells, B cells, monocytes, plasmacytoid dendritic cells and conventional dendritic cells. There were excessive activation of B cells, monocytes and NK cells in PE patients at the pregnant stage based on comparative analysis. Lower immune response activation was noticed in CD4+ and CD8+ T cells in PE patients, especially the low-activation of memory T cells at the pregnant and postpartum stages. PE patients showed high activation of B cells in pregnancy persisted postpartum and lower activation of memory T cells, indicating their persistent effects on the pathogenesis and recurrence risk of PE. This study provide a broad characterization of the single-cell transcriptome of PBMCs in PE, which contributes to identification of immune imbalance for its monitoring and treatment.


Preeclampsia (PE) is characterized by de novo onset of proteinuria or other maternal organ dysfunction and hypertension at gestational age of 20 weeks or more. Its pathogenesis is associated with the abnormal placental development caused by insufficient trophoblast invasion and impaired spiral artery remodeling, and consequent maternal-inflammatory response and endovascular dysfunction. Peripheral immune response may play a crucial role in the pathogenesis of PE. Besides, lower activation of CD4+ memory T cells was related to the onset of PE. However, the roles of the immune cells in PE recurrence are still not well defined. Single-cell RNA sequencing was performed to immune cells in PE patients, which confirmed an excessive inflammatory state in monocytes, NK cells and B cells and lower activation of memory T cells in PE women. Our data showed that PE was associated with the immune imbalance, which may provide potential therapeutic strategies for its treatment.

9.
Foods ; 11(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36360086

RESUMO

The effect of frying temperature on heat transfer, water loss kinetic, oil uptake kinetic, and quality of French fries was evaluated. With increasing frying temperature, the core temperature of fries increased, and the Biot number and heat transfer coefficient (h) first decreased and then increased significantly (p < 0.05). The water loss rate (kw) and water effective diffusion of fries increased with the increasing frying temperature. The kw of fries fried at 150-190 °C were 0.2391, 0.2414, 0.3205, 0.3998, and 0.3931, respectively. The oil uptake rate (ko) first increased and then decreased with increasing frying temperature, and the ko of samples fried at 150-190 °C were 0.2691, 0.2564, 0.4764, 0.3387, and 0.2522, respectively. There were significant differences in the a*, L*, ΔE, and BI between fries with different temperatures (p < 0.05), while there was no significant difference in the b* (p > 0.05). The hardness and crispness of fries increased with increased frying temperature. The highest overall acceptability scores of fries were fried at 170 °C. Therefore, the changes in color, texture overall acceptability, and oil content were due to the Maillard reaction and the formation of porous structure, which was induced by h and water evaporation of fries when they changed.

10.
BMC Med ; 20(1): 380, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36336678

RESUMO

BACKGROUND: Language deficits frequently occur during the prodromal stages of Alzheimer's disease (AD). However, the characteristics of linguistic impairment and its underlying mechanism(s) remain to be explored for the early diagnosis of AD. METHODS: The percentage of silence duration (PSD) of 324 subjects was analyzed, including patients with AD, amnestic mild cognitive impairment (aMCI), and normal controls (NC) recruited from the China multi-center cohort, and the diagnostic efficiency was replicated from the Pitt center cohort. Furthermore, the specific language network involved in the fragmented speech was analyzed using task-based functional magnetic resonance. RESULTS: In the China cohort, PSD increased significantly in aMCI and AD patients. The area under the curve of the receiver operating characteristic curves is 0.74, 0.84, and 0.80 in the classification of NC/aMCI, NC/AD, and NC/aMCI+AD. In the Pitt center cohort, PSD was verified as a reliable diagnosis biomarker to differentiate mild AD patients from NC. Next, in response to fluency tasks, clusters in the bilateral inferior frontal gyrus, precentral gyrus, left inferior temporal gyrus, and inferior parietal lobule deactivated markedly in the aMCI/AD group (cluster-level P < 0.05, family-wise error (FWE) corrected). In the patient group (AD+aMCI), higher activation level of the right pars triangularis was associated with higher PSD in in both semantic and phonemic tasks. CONCLUSIONS: PSD is a reliable diagnostic biomarker for the early stage of AD and aMCI. At as early as aMCI phase, the brain response to fluency tasks was inhibited markedly, partly explaining why PSD was elevated simultaneously.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Testes Neuropsicológicos , Estudos Transversais , Fala , Disfunção Cognitiva/diagnóstico , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/patologia , Encéfalo/patologia , Imageamento por Ressonância Magnética , Estudos de Coortes , Biomarcadores
11.
Artigo em Inglês | MEDLINE | ID: mdl-36361351

RESUMO

The environmental maintenance of public dining spaces significantly impacts urban construction's sustainable and healthy development. This paper studied the influence of image-text information tailoring relationships on behavioral intentions to promote public dining space environment maintenance. We used a two-factor between-subject experimental design, two (image reference points: self vs. others) × two (text appeals: feasibility vs. desirability). We also examined the mediating roles of environmental maintenance attitudes and environmental responsibility perceptions as regards pro-environmental behavioral intentions. The research results showed the following: (1) Among the four image-text information construction methods, the other's image reference point with the desirability text appeal promotes the diners' pro-environmental behavioral intention with optimal effectiveness; and (2) Environmental maintenance attitudes and environmental responsibility perceptions play mediating roles in promoting diners' intention to maintain environmental behavior in the image-text combined information presentation. Environmental responsibility perceptions cannot be mediated alone and must be progressively mediated with environmental maintenance attitudes.


Assuntos
Intenção , Envio de Mensagens de Texto , Atitude , Meio Ambiente
12.
Int J Mol Sci ; 23(21)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36361683

RESUMO

More research is required to understand how melatonin protects neurons. The study aimed to find out if and how long non-coding RNA (lncRNA) contributes to melatonin's ability to defend the hippocampus from H2O2-induced oxidative injury. LncRNAs related to oxidative injury were predicted by bioinformatics methods. Mouse hippocampus-derived neuronal HT22 cells were treated with H2O2 with or without melatonin. Viability and apoptosis were detected by Cell Counting Kit-8 and Hoechst33258. RNA and protein levels were measured by quantitative real-time PCR, Western blot, and immunofluorescence. Bioinformatics predicted that 38 lncRNAs were associated with oxidative injury in mouse neurons. LncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) was related to H2O2-induced oxidative injury and up-regulated by melatonin in HT22 cells. The knockdown of NEAT1 exacerbated H2O2-induced oxidative injury, weakened the moderating effect of melatonin, and abolished the increasing effect of melatonin on the mRNA and protein level of Slc38a2. Taken together, melatonin attenuates H2O2-induced oxidative injury by upregulating lncRNA NEAT1, which is essential for melatonin stabilizing the mRNA and protein level of Slc38a2 for the survival of HT22 cells. The research may assist in the treatment of oxidative injury-induced hippocampal degeneration associated with aging using melatonin and its target lncRNA NEAT1.


Assuntos
Melatonina , MicroRNAs , RNA Longo não Codificante , Camundongos , Animais , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Melatonina/farmacologia , Peróxido de Hidrogênio/toxicidade , Hipocampo/metabolismo , Apoptose/genética , Estresse Oxidativo , RNA Mensageiro/metabolismo , MicroRNAs/genética
13.
Toxins (Basel) ; 14(11)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36356014

RESUMO

In this study, a gas chromatography-mass spectrometry (GC-MS) method was established for the determination of zearalenone and its five derivatives in feed, including zearalanone, α-zearalanol, ß-zearalanol, α-zearalenol, and ß-zearalenol. An effective immunoaffinity column was prepared for sample purification, which was followed by the silane derivatization of the eluate after an immunoaffinity chromatography analysis for target compounds by GC-MS. Matrix effects were corrected by an isotope internal standard of zearalenone in this method. The six analytes had a good linear relationship in the range of 2-500 ng/mL, and the correlation coefficients were all greater than 0.99. The limits of detection (LODs) and limits of quantification (LOQs) were less than 1.5 µg/kg and 5.0 µg/kg, respectively. The average spike recoveries for the six feed matrices ranged from 89.6% to 112.3% with relative standard deviations (RSDs) less than 12.6%. Twenty actual feed samples were analyzed using the established method, and at least one target was detected. The established GC-MS method was proven to be reliable and suitable for the determination of zearalenone and its derivatives in feed.


Assuntos
Zearalenona , Zearalenona/análise , Cromatografia Gasosa-Espectrometria de Massas , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Isótopos
14.
Sensors (Basel) ; 22(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36433613

RESUMO

In view of various security requirements, there are various security services in the network. In particular, DDoS attacks have various types and detection methods. How to flexibly combine security services and make full use of the information provided by security services have become urgent problems to be solved. This paper combines the reasoning ability of the malicious behavior knowledge base to realize the dynamic deployment of the service function chain and dynamic configuration of the security service function. The method feeds back the information generated by the security service to the knowledge base. After the analysis of the knowledge base, the service function chain path and the security service configuration policies are generated, and these policies will be dynamically distributed to the security service function. Finally, security services can be dynamically arranged for different network traffic, realizing the coordinated use of various security services and improving the overall detection rate of the network. The experimental results show that by arranging the paths under the UDP and the TCP, the overall detection rate of the network can reach 99% and 88%, respectively, indicating that it has a good overall detection performance for multiple distributed denial of service (DDoS) attacks.


Assuntos
Segurança Computacional , Bases de Conhecimento
15.
Front Public Health ; 10: 1042618, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438265

RESUMO

Background: As an emerging technology, virtual reality (VR) has been broadly applied in the medical field, especially in neurorehabilitation. The growing application of VR therapy promotes an increasing amount of clinical studies. In this paper, we present a bibliometric analysis of the existing studies to reveal the current research hotspots and guide future research directions. Methods: Articles and reviews on the related topic were retrieved from the Science Citation Index Expanded of Web of Science Core Collection database. VOSviewer and Citespace software were applied to systematically analyze information about publications, countries, institutions, authors, journals, citations, and keywords from the included studies. Results: A total of 1,556 papers published between 1995 and 2021 were identified. The annual number of papers increased gradually over the past three decades, with a peak publication year in 2021 (n = 276). Countries and institutions from North America and Western European were playing leading roles in publications and total citations. Current hotspots were focused on the effectiveness of VR therapy in cognitive and upper limb motor rehabilitation. The clusters of keywords contained the four targeted neurological diseases of VR, while the burst keywords represented that the latest studies were directed toward more defined types of VR therapy and greater study design. Conclusions: Our study offers information regarding to the current hotspots and emerging trends in the VR for rehabilitation field. It could guide future research and application of VR therapy in neurorehabilitation.


Assuntos
Reabilitação Neurológica , Realidade Virtual , Humanos , Bibliometria , América do Norte
16.
Int J Mol Sci ; 23(22)2022 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-36430482

RESUMO

The tree peony (Paeonia section Moutan DC.) is the candidate flower in China, with abundant germplasm resources and high ornamental value. However, the short and concentrated flowering period severely restricted the improvement of the economic value of tree peonies. Based on the full-length transcriptome database of tree peonies, the PoVIN3 (GenBank ID: OP341879), involved in the flowering regulation of tree peonies were identified and cloned for the first time. The PoVIN3 was also characterized by bioinformatics methods, quantitative real-time PCR (qRT-PCR), and the establishment of a transgenic system. The expression levels of PoVIN3 in seven different petals developmental stages were the highest at the initial flowering stage of the variant cultivar of Paeonia ostii 'Fengdan,' the initial decay stage of the normal flowering Paeonia ostii 'Fengdan,' and the half opening stage of the late flowering Paeonia suffruticosa 'Lianhe.' Tissue-specific expression analysis showed that the relative expression levels of PoVIN3 were the highest in sepals of both normal flowering Paeonia ostii 'Fengdan' and the late flowering Paeonia suffruticosa 'Lianhe,' and the highest expression was in stamens of early flowering mutant Paeonia ostii 'Fengdan.' In addition, the flowering time of pCAMBIA2300-PoVIN3 transgenic plants was significantly earlier than that of the wild-type, indicating that PoVIN3 could promote plant flowering. The results provide a theoretical basis for exploring the role of PoVIN3 in the regulation of flowering in tree peonies.


Assuntos
Paeonia , Paeonia/genética , Paeonia/metabolismo , Flores/genética , Transcriptoma , Reação em Cadeia da Polimerase em Tempo Real , China
17.
J Agric Food Chem ; 70(47): 14877-14885, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36382709

RESUMO

Lactic acid bacteria can convert selenium (Se) from inorganic to organic and elemental forms, but the distribution and existence form of organic Se in the bacteria are not clear after Se enrichment, and the effects of selenization on the growth and nutritional value of strains also need to be studied. In this study, Pediococcus acidilactici MRS-7 could absorb up to 67% of inorganic Se and convert most of it into organic Se; about 75% of organic Se was selenoprotein, 2.7% was Se-polysaccharide, and 4.6% was Se-nucleic acid. Additionally, Se-enriched treatment increased the levels of amino acids and essential elements in P. acidilactici MRS-7. Finally, after Se enrichment, Se nanoparticles (SeNPs) were found on the surface of P. acidilactici MRS-7, but they had no harmful effect on its morphology, and its survival during gastrointestinal digestion was not affected, indicating that SeP has potential probiotic value in the food industry.

18.
Nat Commun ; 13(1): 7290, 2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36435942

RESUMO

The combined catalytic systems derived from organocatalysts and transition metals exhibit powerful activation and stereoselective-control abilities in asymmetric catalysis. This work describes a highly efficient chiral aldehyde-nickel dual catalytic system and its application for the direct asymmetric α-propargylation reaction of amino acid esters with propargylic alcohol derivatives. Various structural diversity α,α-disubstituted non-proteinogenic α-amino acid esters are produced in good-to-excellent yields and enantioselectivities. Furthermore, a stereodivergent synthesis of natural product NP25302 is achieved, and a reasonable reaction mechanism is proposed to illustrate the observed stereoselectivity based on the results of control experiments, nonlinear effect investigation, and HRMS detection.


Assuntos
Aldeídos , Aminoácidos , Aldeídos/química , Aminoácidos/química , Níquel , Estereoisomerismo , Catálise , Ésteres
19.
Nephron ; : 1-6, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36446345

RESUMO

BACKGROUND: Hemodialysis (HD) patients have decreased physical function. Getting enough sleep is important for maintaining physical function. However, the relationship between sleep duration and physical performance in HD patients is unclear. METHODS: We conducted a multicenter cross-sectional study at seven HD centers in Shanghai and Suzhou, China. 880 HD patients were enrolled between July 2020 and April 2021. Clinical Characteristics, laboratory indicator, sleep assessment data were collected. Physical performance included balance function, muscle strength, and mobility, which were measured by timed up and go test (TUGT), handgrip, and 4-m walk test, respectively. We divided sleep duration into four groups <7 h, 7-8 h, >8-9 h, ≥9 h. RESULTS: A total of 840 patients had completed data (men 525, women 315, mean age 61.24 years). TUGT in group <7 h and ≥9 h was higher than mid-range sleep duration. Handgrip strength in group ≥9 h was lower than group <7 h and 7-8 h. Gait speed in group <7 h and ≥9 h was lower than group 7-8 h. Adjusting for the covariates, short and long sleep duration were associated with slower gait speed. CONCLUSION: HD patients with abnormal sleep duration had poorer physical performance. Short and long sleep duration were significantly associated with gait speed.

20.
J Int Med Res ; 50(11): 3000605221136683, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36446755

RESUMO

OBJECTIVE: To determine whether a relationship exists between sarcopenia, including its individual components (muscle mass, muscle strength and gait speed), and mild-to-moderate chronic kidney disease (CKD) in Chinese older adults. METHODS: This cross-sectional study comprised participants aged ≥60 years from Tianjin and Shanghai, China, who joined a national free physical examination program between 2014 and 2019, and consented to study inclusion. Sarcopenia was defined according to the Asian Working Group for Sarcopenia (2019 version). Mild-to-moderate CKD was defined as estimated glomerular filtration rate (eGFR) between 45 ml/min/1.73 m2 and 60 ml/min/1.73 m2. RESULTS: A total of 1627 participants were included (mean age, 69.32 ± 6.17 years; 43.8% male). Sarcopenia was significantly associated with mild-to-moderate CKD in men but not women. Among three physical performance components, slow gait speed (odds ratio 1.89, 95% confidence interval 1.38, 2.58) was associated with mild-to-moderate CKD in both men and women after adjusting for all other variables. CONCLUSIONS: Sarcopenia was closely associated with mild-to-moderate CKD in older men, and slow gait speed was related to mild-to-moderate CKD in men and women. These findings may help guide better diagnosis and management of CKD in the context of slow gait speed, and facilitate earlier CKD detection and appropriate intervention in older adults.

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