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An efficient method was discovered for catalyzing the esterification under air using Novozym 435 to obtain pyridine esters. The following conditions were found to be optimal: 60 mg of Novozyme 435, 5.0 mL of n-hexane, a molar ratio of 2:1 for nicotinic acids (0.4 mmol) to alcohols (0.2 mmol), 0.25 g of molecular sieve 3A, a revolution speed of 150 rpm, a reaction temperature of 50 °C, and reaction time of 48 h. Under nine cycles of Novozym 435, the 80 % yield was consistently obtained. Optimum conditions were used to synthesize 23 pyridine esters, including five novel compounds. Among them, gas chromatography-mass spectrometry-olfactometry (GC-MS-O) showed phenethyl nicotinate (3g), (E)-hex-4-en-1-yl nicotinate (3m), and octyl nicotinate (3n) possessed strong aromas. Thermogravimetric analysis (TG) revealed that the compounds 3g, 3m and 3n exhibited stability at the specified temperature. This finding provides theoretical support for adding pyridine esters fragrance to high-temperature processed food.
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Nitroxyl (HNO), a reactive nitrogen species (RNS), is essential for plant growth. However, the action of HNO in plants has been difficult to understand due to the lack of highly sensitive and real-time in-situ monitoring tools. Herein, we presented a near-infrared fluorescent probe, DCI-HNO, based on dicyanoisophorone fluorophore, for real-time mapping HNO in plants. The introduction of a phosphine moiety as a specific HNO recognition unit can inhibit the intramolecular charge transfer (ICT) of probe DCI-HNO. However, in the presence of HNO, the ICT process occurred, leading to the emission at 665 nm. Probe DCI-HNO exhibited high sensitivity (97 nM), rapid response time (8 min), large Stokes shift (135 nm) for detection of HNO in plants. The novel developed probe has successfully imaged endogenous HNO produced during NO/H2S cross-talk in plant tissues. Additionally, the up-regulated in HNO levels during tobacco aging and in response to stress has been confirmed. Therefore, probe DCI-HNO has provided a reliable method for monitoring the NO/H2S cross-talk and revealing the role of HNO in plants.
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Corantes Fluorescentes , Óxidos de Nitrogênio , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Óxidos de Nitrogênio/análise , Óxidos de Nitrogênio/química , Nicotiana/química , Nicotiana/metabolismo , Espectrometria de Fluorescência/métodos , Plantas/química , Plantas/metabolismoRESUMO
Six low molecular weight fenugreek polysaccharides (FP) were isolated and purified by ethanol stepwise precipitation (EFP-20, EFP-40, and EFP-60) and DEAE-52 cellulose column method (DFP-0, DFP-0.15, and DFP-0.3), respectively. The effects of different separation and purification techniques on the preliminary properties and biological activities of fenugreek polysaccharides were compared. The results showed that the DEAE-52 cellulose-eluted fractions had a higher total sugar content and displayed a looser structure. The molecular weights of all six fractions were in the range of 4-19â kDa, with significant changes in the ratio of galactose to mannose. All six fractions contained α-D-galactopyranose and ß-D-mannopyranose structures. Activity tests showed that all six fractions possessed antioxidant, hypoglycemic and DNA-protective activities. Among them, the DFP-0 fraction showed the highest activity. Overall, different isolation and purification methods lead to changes in the properties and bioactivities of FP, which provides a theoretical basis for the development and application of FP in functional foods and drugs.
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Antioxidantes , DNA , Hipoglicemiantes , Polissacarídeos , Trigonella , Trigonella/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Polissacarídeos/química , Hipoglicemiantes/farmacologia , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/química , DNA/química , Animais , Peso MolecularRESUMO
BACKGROUND: Temperature affects influenza transmission; however, currently, limited evidence exists about its effect in China at the national and city levels as well as how temperature can be integrated into influenza interventions. METHODS: Meteorological, pollutant, and influenza data from 201 cities in mainland China between 2013 and 2018 were analyzed at both the city and national levels to investigate the relationship between temperature and influenza prevalence. We examined the impact of temperature on the time-varying reproduction number (Rt) using generalized additive quasi-Poisson regression models combined with the distributed lag nonlinear model. Threshold temperatures were determined for seven regions based on the early warning threshold of serious influenza outbreaks, set at Rt = 1.2. A multivariate random-effects meta-analysis was employed to assess region-specific associations. The excess risk (ER) index was defined to investigate the correlation between Rt and temperature, modified based on seasonal and regional characteristics. RESULTS: At the national level and in the central, northern, northwestern, and southern regions, temperature was found to be negatively correlated with relative risk, whereas the shapes of the data curves for the eastern, southwestern, and northeastern regions were not well defined. Low temperatures had an observable effect on influenza prevalence; however, the effects of high temperatures were not obvious. At an Rt of 1.2, the threshold temperatures for reaching a warning for serious influenza outbreaks were - 24.3 °C in the northeastern region, 16.6 °C in the northwestern region, and between 1â and 10 °C in other regions. CONCLUSION: The study findings revealed that temperature had a varying effect on influenza transmission trends (Rt) across different regions in China. By identifying region-specific temperature thresholds at Rt = 1.2, more effective early warning systems for influenza outbreaks could be tailored. These findings emphasize the significance of the region-specific adaptation of influenza prevention and control measures.
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Cidades , Influenza Humana , Temperatura , China/epidemiologia , Influenza Humana/epidemiologia , Humanos , Cidades/epidemiologia , Prevalência , Estações do AnoRESUMO
Plant viral diseases can seriously affect the yield and quality of crops. In this work, a convenient and highly sensitive biosensor for the visual detection of plant viral disease is proposed by the PCR-induced generation of DNAzyme. In the absence of nucleic acid for a target plant virus, the primers prohibited the production of G-quadruplex by forming a hairpin structure. However, PCR amplification occurred and generated a number of specific PCR products with free G-quadruplex sequences at both ends in the presence of the target cDNA. A catalytically active G-quadruplex DNAzyme was formed with the help of K+ and hemin, resulting in the formation of colored products visible to the naked eye and a strong absorbance by the addition of ABTS2- and H2O2. The absorbance and the logarithm of target cDNA concentrations showed a good linear relationship in the range of 10 fM-1.0 nM, with a linear regression equation of A = 0.1402 lg c + 0.3761 (c: fM) and a detection limit of 0.19 fM. This method was successfully applied to the analysis of emerging tobacco mosaic virus (TMV) infections in tobacco leaf samples collected in the field due to its flexibility and convenience, indicating a potential application for the early detection of plant viral disease.
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DNA Catalítico , Vírus de Plantas , Viroses , Humanos , DNA Catalítico/química , DNA Complementar , Peróxido de Hidrogênio/química , Vírus de Plantas/genética , Reação em Cadeia da PolimeraseRESUMO
To develop new chemicals that are stable at high temperatures with biological activity, a pyrrole intermediate was firstly synthesized using glucosamine hydrochloride as raw materials through cyclization and oxidation. Further, two novel pyrrole ester derivatives were prepared via Steglich esterification from pyrrole intermediate with vanillin and ethyl maltol, respectively. Nuclear magnetic resonance (1 H-NMR, 13 C NMR), infrared spectroscopy (IR) and high resolution mass spectrometry (HRMS) were used to confirm the target compounds. Thermal behavior of the compounds was investigated by thermogravimetry (TG), differential scanning calorimeter (DSC) and the pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) methods. The plausible pyrolytic mechanism was proposed. Additionally, their biological activities against the pathogens Fusarium graminearum, Fusarium oxysporum, Fusarium moniliforme, Phytophthora nicotianae, and Rhizoctonia solani were assessed. These target compounds showed outstanding antifungal activities and the highest inhibitor rates of 62.50 % and 68.75 % against R. solani with EC50 values of 0.0296 and 0.0200â mg mL-1 , respectively. SDHI protein sequence was molecularly docked to identify the binding mechanisms in the active pocket and examine the interactions between both the molecules and the SDHI protein.
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Antifúngicos , Fusarium , Antifúngicos/química , Ésteres/farmacologia , Pirróis/farmacologia , Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Relação Estrutura-AtividadeRESUMO
Polysaccharides possess excellent moisturizing effects due to their abundance of hydrophilic groups and film-forming properties. Additionally, they can produce a refreshing aroma during the pyrolysis process. However, there is scarce research on their application in the tobacco field. Herein, we investigated the effects of low molecular weight fenugreek polysaccharide (FP) obtained through ethanol fractionation and DEAE-52 cellulose column chromatography on moisture retention and aroma enhancement in tobacco. The moisture retention test revealed that the addition of FP increased the moisture retention index (MRI) of tobacco by 11.72 %-16.69 %, indicating that the hydrophilic nature of polysaccharides facilitated the migration of free water in tobacco to bound water, resulting in reduced water activity. Moreover, the contact angle between polysaccharide and tobacco was <90°, enabling better infiltration into tobacco and slowing down tobacco shrinkage caused by water loss. Among all the components, EFP-20 and EFP-40 demonstrated superior performance. Furthermore, FP exhibited excellent thermal stability below 200 °C and can decomposed to produce aromatic substances at high temperatures. It also demonstrated the ability to adsorb ethyl heptanoate and thermally decompose to produce a substantial amount of heptanoic acid. Consequently, the incorporation of FP in tobacco demonstrated favorable effects on both moisturization and aroma enhancement.
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Produtos do Tabaco , Trigonella , Odorantes/análise , Peso Molecular , Polissacarídeos/farmacologia , Polissacarídeos/química , Água/químicaRESUMO
Sulfur dioxide (SO2) is emerging as a double-edged molecule, while plays vital roles in food and biological system. However, the fast, highly sensitive, and versatile fluorescent probe still remains a tough challenge among current reports. Herein, we developed a novel aggregation-induced emission (AIE) fluorescent probe TPE-PN for specifically sensing SO2 derivatives with high sensitivity (150 nmol/L) and rapid response time (10 s) based on intramolecular charge transfer (ICT) mechanism. And the fluorescence at 575 nm decreased tremendously with 31-fold after the probe was treated with HSO3-. Employing the probe, the accurate analysis of HSO3- was successfully realized in food samples, cells, plant tissues, and zebrafishes. Furthermore, we successfully demonstrate the eruption of SO2 derivatives within plant during drought and salt stress processes. Therefore, probe TPE-PN illustrates significant potential for applications in food analysis and monitoring of SO2 derivatives levels in biological systems under stress conditions.
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Corantes Fluorescentes , Mitocôndrias , Humanos , Fluorescência , Mitocôndrias/química , Dióxido de Enxofre/análise , Células HeLaRESUMO
OBJECTIVE: Kratom ( Mitragyna speciosa ) use in pregnancy is associated with maternal and neonatal opioid withdrawal syndrome. However, kratom use patterns in the population of peripartum and postpartum individuals with substance use disorder (SUD) are unknown. The aim of this study was to determine the proportion of pregnant and postpartum individuals with SUD who report using kratom in pregnancy or lactation and the reasons for their use. METHODS: We conducted an anonymous survey of pregnant and postpartum individuals receiving care at a single center's multidisciplinary prenatal clinic for individuals with SUD. We collected participants' demographic and pregnancy characteristics. We assessed ever use of kratom, kratom use during pregnancy or lactation, and reasons for kratom use. Descriptive statistics were used to summarize the data. RESULTS: From January 2021 to May 2021, a total of 80 surveys were collected (81% response rate of 98 eligible individuals). Most respondents were pregnant (n = 50 [62.5%]). The most frequent substance(s) of use were opioids (n = 50 [62.5%]) and methamphetamine (n = 39 [48.8%]). Many (n = 26 [32.5%]) reported ever use of kratom use. Of all respondents, 4 (5%) reported use during pregnancy, and 1 (1%) reported use during lactation. Kratom was primarily used to relieve opioid withdrawal symptoms and for relaxation, pain control, and stress relief. CONCLUSION: In a survey of pregnant and postpartum individuals with SUD at a single high-risk pregnancy clinic, ever use of kratom was frequent, whereas peripartum use was rare.
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Mitragyna , Síndrome de Abstinência a Substâncias , Transtornos Relacionados ao Uso de Substâncias , Feminino , Gravidez , Recém-Nascido , Humanos , Lactação , Analgésicos OpioidesRESUMO
In the present work a simple enzymatic approach (Novozym 435) for transesterification to synthesize pyrrole esters was reported. To generate the best reaction conditions, which resulted in the optimum yield of 92%, the effects of lipase type, solvent, lipase load, molecular sieves, substrate molar ratio of esters to alcohol, reaction temperature, reaction duration, and speed of agitation were evaluated. The range of alcohols was assessed under optimal circumstances. The spectrum observations conclusively demonstrated that the compounds could be generated with high yield under the circumstances utilized for synthesis. The odor characteristics of the pyrrolyl esters obtained were examined by gas chromatography-mass spectrometry-olfactometry (GC-MS-O). Among them, compounds of benzhydryl 1H-pyrrole-2-carboxylate (3j), butyl 1H-pyrrole-2-carboxylate (3k) and pentyl 1H-pyrrole-2-carboxylate (3l) present sweet and acid aroma. In addition, the thermal degradation process was further studied using the Py-GC/MS (pyrolysis-gas chromatography/mass spectrometry), TG (thermogravimetry), and DSC (differential scanning calorimeter) techniques. The outcomes of the Py-GC/MS, TG, and DSC techniques show that they have excellent thermal stability.
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Cadmium (Cd) removal from soil to reduce Cd accumulation in plants is essential for agroecology, food safety, and human health. Cd enters plants from soil and affects plant growth and development. Hydrogels can easily combine with Cd, thereby altering its bioavailability in soil. However, few studies have evaluated the effects of hydrogel on the complex phytotoxicity caused by Cd uptake in plants and the microbial community structure. Herein, a new poly (acrylic acid)-grafted starch and potassium humate composite (S/K/AA) hydrogel was added to soil to evaluate its impact on tobacco growth and the soil microenvironment. The results indicate that the addition of S/K/AA hydrogel can significantly improve the biomass, chlorophyll (Chl) content, and photosynthetic capacity of tobacco plants during Cd stress conditions, and decrease Cd concentration, probably by affecting Cd absorption through the expression of Cd absorption transporters (e.g., NRAMP5, NRAMP3, and IRT1). Moreover, the application of S/K/AA hydrogel not only reduced the accumulation of reactive oxygen species (ROS), but also reduced the antioxidant activities of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT), suggesting that S/K/AA hydrogel alleviates Cd toxicity via a non-antioxidant pathway. Notably, we further analyzed the effectiveness of the hydrogel on microbial communities in Cd-contaminated soil and found that it increased the Cd-tolerant microbial community (Arthrobacter, Massilia, Streptomyces), enhancing the remediation ability of Cd-contaminated soil and helping tobacco plants to alleviate Cd toxicity. Overall, our study provides primary insights into how S/K/AA hydrogel affects Cd bioavailability and alleviates Cd toxicity in plants.
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Arthrobacter , Cádmio , Humanos , Cádmio/toxicidade , Disponibilidade Biológica , Nicotiana , HidrogéisRESUMO
Background: Evidence is inefficient about how meteorological factors influence the trends of influenza transmission in different regions of China. Methods: We estimated the time-varying reproduction number (Rt) of influenza and explored the impact of temperature and relative humidity on Rt using generalized additive quasi-Poisson regression models combined with the distribution lag non-linear model (DLNM). The effect of temperature and humidity interaction on Rt of influenza was explored. The multiple random-meta analysis was used to evaluate region-specific association. The excess risk (ER) index was defined to investigate the correlation between Rt and each meteorological factor with the modification of seasonal and regional characteristics. Results: Low temperature and low relative humidity contributed to influenza epidemics on the national level, while shapes of merged cumulative effect plots were different across regions. Compared to that of median temperature, the merged RR (95%CI) of low temperature in northern and southern regions were 1.40(1.24,1.45) and 1.20 (1.14,1.27), respectively, while those of high temperature were 1.10(1.03,1.17) and 1.00 (0.95,1.04), respectively. There were negative interactions between temperature and relative humidity on national (SI = 0.59, 95%CI: 0.57-0.61), southern (SI = 0.49, 95%CI: 0.17-0.80), and northern regions (SI = 0.59, 95%CI: 0.56,0.62). In general, with the increase of the change of the two meteorological factors, the ER of Rt also gradually increased. Conclusions: Temperature and relative humidity have an effect on the influenza epidemics in China, and there is an interaction between the two meteorological factors, but the effect of each factor is heterogeneous among regions. Meteorological factors may be considered to predict the trend of influenza epidemic.
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OBJECTIVE: The objective of this study is to explore pregnant and postpartum individuals' knowledge, attitudes, and perceptions regarding extended-release buprenorphine (XR-BUP) treatment for opioid use disorder. METHODS: We conducted a paper-based survey of pregnant or postpartum individuals with opioid use disorder attending a multidisciplinary perinatal addiction specialty care clinic where XR-BUP is available. Participants' nonidentifiable demographic and treatment characteristics were collected, including duration and satisfaction of current medication for opioid use disorder. Participants' knowledge, attitudes, and perceptions about XR-BUP were assessed using a 5-point Likert scale. Descriptive statistics were used to summarize the data. RESULTS: From February 2021 to August 2021, 79 of 98 eligible participants completed the survey (81% response rate). More than 9 of 10 participants were currently taking medication for opioid use disorder, and 7 individuals (8.9%) were taking XR-BUP. Nearly half (49.4%) had never heard of XR-BUP, and 84.8% did not personally know anyone taking XR-BUP. However, 45.6% and 29.1% would consider an injectable medication for opioid use disorder to avoid trouble remembering to take their daily medications and avoid opioid withdrawal symptoms, respectfully. CONCLUSIONS: In a population of pregnant and postpartum individuals, nearly half were unaware of a monthly XR-BUP option for the treatment of opioid use disorder. Many were interested in considering this medication. Future studies are needed to rigorously assess outcomes associated with XR-BUP among pregnant and postpartum individuals with opioid use disorder.
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Buprenorfina , Transtornos Relacionados ao Uso de Opioides , Feminino , Humanos , Gravidez , Buprenorfina/uso terapêutico , Antagonistas de Entorpecentes/uso terapêutico , Naltrexona/uso terapêutico , Conhecimentos, Atitudes e Prática em Saúde , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Preparações de Ação Retardada/uso terapêuticoRESUMO
Knowledge of viral shedding remains limited. Repeated measurement data have been rarely used to explore the influencing factors. In this study, a joint model was developed to explore and validate the factors influencing the duration of viral shedding based on longitudinal data and survival data. We divided 361 patients infected with Delta variant hospitalized in Nanjing Second Hospital into two groups (≤ 21 days group and > 21 days group) according to the duration of viral shedding, and compared their baseline characteristics. Correlation analysis was performed to identify the factors influencing the duration of viral shedding. Further, a joint model was established based on longitudinal data and survival data, and the Markov chain Monte Carlo algorithm was used to explain the influencing factors. In correlation analysis, patients having received vaccination had a higher antibody level at admission than unvaccinated patients, and with the increase of antibody level, the duration of viral shedding shortened. The linear mixed-effects model showed the longitudinal variation of logSARS-COV-2 IgM sample/cutoff (S/CO) values, with a parameter estimate of 0.193 and a standard error of 0.017. Considering gender as an influencing factor, the parameter estimate of the Cox model and their standard error were 0.205 and 0.1093 (P = 0.608), the corresponding OR value was 1.228. The joint model output showed that SARS-COV-2 IgM (S/CO) level was strongly associated with the risk of a composite event at the 95% confidence level, and a doubling of SARS-COV-2 IgM (S/CO) level was associated with a 1.38-fold (95% CI: [1.16, 1.72]) increase in the risk of viral non-shedding. A higher antibody level in vaccinated patients, as well as the presence of IgM antibodies in serum, can accelerate shedding of the mutant virus. This study provides some evidence support for vaccine prevention and control of COVID-19 variants.
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COVID-19 , Humanos , SARS-CoV-2 , Eliminação de Partículas Virais , Imunoglobulina MRESUMO
Ferroptosis is a newly discovered form of regulated cellular demise, characterized by the accumulation of intracellular oxidative stress that is dependent on iron. Ferroptosis plays a crucial role not only in the development and treatment of tumors but also in the pathogenesis of neurodegenerative diseases and illnesses related to ischemia-reperfusion injury. This mode of cell death possesses distinctive properties that differentiate it from other forms of cell death, including unique morphological changes at both the cellular and subcellular levels, as well as molecular features that can be detected using specific methods. The use of fluorescent probes has become an invaluable means of detecting ferroptosis, owing to their high sensitivity, real-time in situ monitoring capabilities, and minimal damage to biological samples. This review comprehensively elucidates the physiological mechanisms underlying ferroptosis, while also detailing the development of fluorescent probes capable of detecting ferroptosis-related active species across various cellular compartments, including organelles, the nucleus, and the cell membrane. Additionally, the review explores how the dynamic changes and location of active species from different cellular compartments can influence the ignition and execution of ferroptotic cell death. Finally, we discuss the future challenges and opportunities for imaging ferroptosis. We believe that this review will not only aid in the elucidation of ferroptosis's physiological mechanisms but also facilitate the identification of novel treatment targets and means of accurately diagnosing and treating ferroptosis-related diseases.
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Ferroptose , Corantes Fluorescentes , Morte Celular , Ferro/metabolismo , Estresse OxidativoRESUMO
Nickel-catalyzed amidation of aryl alkynyl acids using tetraalkylthiuram disulfides as the amine source is described, affording a series of aryl alkynyl amides in good to excellent yields under mild conditions. This general methodology provides an alternative pathway for the synthesis of useful aryl alkynyl amides in an operationally simple manner, which shows its practical synthetic value in organic synthesis. The mechanism of this transformation was explored through control experiments and DFT calculations.
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BACKGROUND: Chest computerized tomography (CT) scan is an important strategy that quantifies the severity of COVID-19 pneumonia. To what extent inactivated COVID-19 vaccines could impact the COVID-19 pneumonia on chest CT is not clear. METHODS: This study recruited 357 SARS-COV-2 B.1.617.2 (Delta) variant-infected patients admitted to the Second Hospital of Nanjing from July to August 2021. An artificial intelligence-assisted CT imaging system was used to quantify the severity of COVID-19 pneumonia. We compared the volume of infection (VOI), percentage of infection (POI) and chest CT scores among patients with different vaccination statuses. RESULTS: Of the 357 Delta variant-infected patients included for analysis, 105 were unvaccinated, 72 were partially vaccinated and 180 were fully vaccinated. Fully vaccination had the least lung injuries when quantified by VOI (median VOI of 222.4 cm3, 126.6 cm3 and 39.9 cm3 in unvaccinated, partially vaccinated and fully vaccinated, respectively; p < 0.001), POI (median POI of 7.60%, 3.55% and 1.20% in unvaccinated, partially vaccinated and fully vaccinated, respectively; p < 0.001) and chest CT scores (median CT score of 8.00, 6.00 and 4.00 in unvaccinated, partially vaccinated and fully vaccinated, respectively; p < 0.001). After adjustment for age, sex, comorbidity, time from illness onset to hospitalization and viral load, fully vaccination but not partial vaccination was significantly associated with less lung injuries quantified by VOI {adjust coefficient[95%CI] for "full vaccination": - 106.10(- 167.30,44.89); p < 0.001}, POI {adjust coefficient[95%CI] for "full vaccination": - 3.88(- 5.96, - 1.79); p = 0.001} and chest CT scores {adjust coefficient[95%CI] for "full vaccination": - 1.81(- 2.72, - 0.91); p < 0.001}. The extent of reduction of pulmonary injuries was more profound in fully vaccinated patients with older age, having underlying diseases, and being female sex, as demonstrated by relatively larger absolute values of adjusted coefficients. Finally, even within the non-severe COVID-19 population, fully vaccinated patients were found to have less lung injuries. CONCLUSION: Fully vaccination but not partially vaccination could significantly protect lung injury manifested on chest CT. Our study provides additional evidence to encourage a full course of vaccination.
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Vacinas contra COVID-19 , COVID-19 , Lesão Pulmonar , Feminino , Humanos , Masculino , Inteligência Artificial , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Lesão Pulmonar/diagnóstico por imagem , SARS-CoV-2RESUMO
To overcome the shortcomings of high relative humidity and harmful oxidation products from traditional humectants, excellent humectants and flavor precursors were reported herein. Glucosamine hydrochloride was used as the starting material for the cyclization, oxidation, and alkylation processes that produced pyrrole acid. Then, esterification occurred with polyol catalyzed by EDC and DMAP to give the target compounds 2-(2,3-dihydroxypropyl) 4-methyl 5-methyl-1-propyl-1H-pyrrole-2,4-dicarboxylate (Gpe) and (2-hydroxypropyl) 4-methyl 5-methyl-1-propyl-1H-pyrrole-2,4-dicarboxylate (Ppe). Nuclear magnetic resonance (1H NMR, 13C NMR), infrared spectroscopy (IR), and high-resolution mass recorded spectrometry (HRMS) were used to confirm the two novel polyol pyrrole ester compounds. When Gpe and Ppe were added to the tobacco shred, low-field nuclear magnetic resonance (LF-NMR) imaging was applied to assess the hygroscopicity and moisturizing capacity. Furthermore, thermogravimetry (TG) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) techniques were applied to study their thermal behaviors. These results showed that the target compounds (Gpe and Ppe) are good humectants with thermal properties of high-temperature stability and flavor release.
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High temperature in summer is an unfavorable factor for passion fruit (Passiflora edulis), which can lead to restricted growth, short flowering period, few flower buds, low fruit setting rate, severe fruit drop, and more deformed fruit. To explore the molecular physiology mechanism of passion fruit responding to high-temperature stress, we use 'Zhuangxiang Mibao', a hybrid passion fruit cultivar, as the test material. Several physiological indicators were measured and compared between high-temperature (average temperature 38 °C) and normal temperature (average temperature 25 °C) conditions, including photosynthesis, chlorophyll fluorescence parameters, peroxidase activity (POD), superoxide dismutase activity (SOD) and malondialdehyde content. We performed RNA-seq analysis combined with biochemistry experiment to investigate the gene and molecular pathways that respond to high-temperature stress. The results showed that some physiological indicators in the high-temperature group, including the net photosynthetic rate, stomatal conductance, intercellular CO2 concentration, transpiration rate, and the maximum chemical quantum yield of photosystemII (PSII), were significantly lower than those of the control group. Malondialdehyde content was substantially higher than the control group, while superoxide dismutase and superoxide dismutase activities decreased to different degrees. Transcriptome sequencing analysis showed that 140 genes were up-regulated and 75 genes were down-regulated under high-temperature stress. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation analysis of differentially expressed genes revealed many metabolic pathways related to high-temperature stress. Further investigation revealed that 30 genes might be related to high-temperature stress, such as chlorophyllide a oxygenase (CAO), glutathione (GSH), WRKY transcription factors (WRKY), and heat shock protein (HSP), which have also been reported in other species. The results of real-time fluorescence quantitative PCR and RNA-seq of randomly selected ten genes are consistent, which suggests that the transcriptome sequencing results were reliable. Our study provides a theoretical basis for the mechanism of passion fruit response to high-temperature stress. Also, it gives a theoretical basis for the subsequent breeding of new heat-resistant passion fruit varieties.
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Passiflora , Temperatura , Passiflora/genética , Frutas/metabolismo , Melhoramento Vegetal , Perfilação da Expressão Gênica , Superóxido Dismutase/metabolismo , MalondialdeídoRESUMO
A novel approach for converting N-substituted acetylpyrroles and primary alcohols into N-substituted pyrrolyl chalcones in air with the assistance of t-BuOK is reported, and several prominent flavor and bioactive molecules were obtained. The process entails oxidizing the alcohols to the corresponding aldehydes, and t-BuOK is crucial to the effective production of CîC bonds by aldol condensation. Gas chromatography-mass spectrometry-olfactometry (GC-MS-O) was used to examine the odor properties of pyrrolyl chalcones, which are usually different from those of the associated acetylpyrroles and alcohols. The biological evaluation assay showed that the products (E)-3-(3-fluorophenyl)-1-(1-methyl-1H-pyrrol-2-yl)prop-2-en-1-one (3j), (E)-1-(1-ethyl-1H-pyrrol-2-yl)-3-phenylprop-2-en-1-one (4a), (E)-3-(4-bromophenyl)-1-(1-ethyl-1H-pyrrol-2-yl)prop-2-en-1-one (4e), (E)-3-(4-chlorophenyl)-1-(1-ethyl-1H-pyrrol-2-yl)prop-2-en-1-one (4f) and (E)-1-(1-ethyl-1H-pyrrol-2-yl)-3-(4-fluorophenyl)prop-2-en-1-one (4g) exhibited excellent inhibitory activity against R. solani with EC50 values from 0.0107 to 0.0134 mg mL-1. Molecular docking of 3j with SDH (succinate dehydrogenase) was performed to reveal the binding modes in the active pocket and analyze the interactions between the molecules and the SDH protein. Meanwhile, they have good thermal stability according to the results of thermogravimetry (TG) analysis.