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1.
Genome Res ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38951026

RESUMEN

mRNA-based vaccines and therapeutics are gaining popularity and usage across a wide range of conditions. One of the critical issues when designing such mRNAs is sequence optimization. Even small proteins or peptides can be encoded by an enormously large number of mRNAs. The actual mRNA sequence can have a large impact on several properties including expression, stability, immunogenicity, and more. To enable the selection of an optimal sequence, we developed CodonBERT, a large language model (LLM) for mRNAs. Unlike prior models, CodonBERT uses codons as inputs which enables it to learn better representations. CodonBERT was trained using more than 10 million mRNA sequences from a diverse set of organisms. The resulting model captures important biological concepts. CodonBERT can also be extended to perform prediction tasks for various mRNA properties. CodonBERT outperforms previous mRNA prediction methods including on a new flu vaccine dataset.

2.
Transfusion ; 64(6): 1025-1039, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38661221

RESUMEN

BACKGROUND: Limited studies have explored the association between clinical symptoms and titers of SARS-CoV-2 antibodies. STUDY DESIGN AND METHODS: In this cross-sectional study, whole-blood donors who had experienced a confirmed or suspected COVID-19 infection completed questionnaires at the time of blood donation. Plasma SARS-CoV-2 immunoglobulin G (IgG) titers were measured using an enzyme-linked immunosorbent assay. Logistic regression models were used to calculate odds ratios (ORs) for high-titer COVID-19 convalescent plasma (CCP) for each variable. RESULTS: Among the total 386 donors, 120 (31%) donors with IgG titers ≥1:160 were classified as high-titer donors. The multivariable ORs (95% confidence intervals [CIs]) for high titers were 2.33 (1.45-3.75), 2.11 (1.29-3.43), 1.10 (1.01-1.21), 1.19 (1.00-1.43), and 1.97 (1.05-3.71) for sore throat, cough, symptom count, fever duration, and low fever (compared with non-fever), respectively. No significant association was observed between other symptoms and medical visits and the odds of high-titer CCP. The association between high-titer CCP and fever duration was restricted to confirmed COVID-19-infected donors, while associations with sore throat and cough remained significant in suspected infected donors. In addition, medical visit was positively associated with high-titer CCP in suspected donors, but not in confirmed donors. In bootstrapped logistic regression models, the associations remained significant and reproducible for medical visit in suspected donors and for sore throat and cough in both suspected donors and total donors. DISCUSSION: Experiencing a sore throat and cough were associated with high-titer CCP in overall donors. We also identified sore throat, cough, and medical visits as potential predictors of high-titer CCP for suspected donors during the pandemic.


Asunto(s)
Anticuerpos Antivirales , Donantes de Sangre , Sueroterapia para COVID-19 , COVID-19 , Inmunoglobulina G , SARS-CoV-2 , Humanos , COVID-19/sangre , COVID-19/inmunología , COVID-19/epidemiología , Donantes de Sangre/estadística & datos numéricos , Masculino , Femenino , SARS-CoV-2/inmunología , Adulto , Inmunoglobulina G/sangre , Estudios Transversales , Anticuerpos Antivirales/sangre , China/epidemiología , Persona de Mediana Edad , Inmunización Pasiva , Adulto Joven , Tos
3.
PLoS Biol ; 17(3): e3000169, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30822302

RESUMEN

CD1d-restricted invariant natural killer T (iNKT) cells represent a heterogeneous population of lipid-reactive T cells that are involved in many immune responses, mediated through T-cell receptor (TCR)-dependent and/or independent activation. Although numerous microbial lipid antigens (Ags) have been identified, several lines of evidence have suggested the existence of relevant Ags of endogenous origin. However, the identification of their precise nature as well as the molecular mechanisms involved in their generation are still highly controversial and ill defined. Here, we identified two mammalian gangliosides-namely monosialoganglioside GM3 and disialoganglioside GD3-as endogenous activators for mouse iNKT cells. These glycosphingolipids are found in Toll-like receptor-stimulated dendritic cells (DC) as several species varying in their N-acyl fatty chain composition. Interestingly, their ability to activate iNKT cells is highly dependent on the ceramide backbone structure. Thus, both synthetic GM3 and GD3 comprising a d18:1-C24:1 ceramide backbone were able to activate iNKT cells in a CD1d-dependent manner. GM3 and GD3 are not directly recognized by the iNKT TCR and required the Ag presenting cell intracellular machinery to reveal their antigenicity. We propose a new concept in which iNKT cells can rapidly respond to pre-existing self-molecules after stress-induced structural changes in CD1d-expressing cells. Moreover, these gangliosides conferred partial protection in the context of bacterial infection. Thus, this report identified new biologically relevant lipid self-Ags for iNKT cells.


Asunto(s)
Ceramidas/metabolismo , Gangliósidos/metabolismo , Células T Asesinas Naturales/metabolismo , Receptor Toll-Like 9/metabolismo , Animales , Antígenos CD1d/metabolismo , Células de la Médula Ósea/metabolismo , Células Dendríticas/metabolismo , Gangliósido G(M3)/metabolismo , Glicoesfingolípidos/metabolismo , Masculino , Ratones Endogámicos C57BL , Reacción en Cadena en Tiempo Real de la Polimerasa
4.
RNA ; 23(5): 770-781, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28213527

RESUMEN

Accurate thermodynamic parameters improve RNA structure predictions and thus accelerate understanding of RNA function and the identification of RNA drug binding sites. Many viral RNA structures, such as internal ribosome entry sites, have internal loops and bulges that are potential drug target sites. Current models used to predict internal loops are biased toward small, symmetric purine loops, and thus poorly predict asymmetric, pyrimidine-rich loops with >6 nucleotides (nt) that occur frequently in viral RNA. This article presents new thermodynamic data for 40 pyrimidine loops, many of which can form UU or protonated CC base pairs. Uracil and protonated cytosine base pairs stabilize asymmetric internal loops. Accurate prediction rules are presented that account for all thermodynamic measurements of RNA asymmetric internal loops. New loop initiation terms for loops with >6 nt are presented that do not follow previous assumptions that increasing asymmetry destabilizes loops. Since the last 2004 update, 126 new loops with asymmetry or sizes greater than 2 × 2 have been measured. These new measurements significantly deepen and diversify the thermodynamic database for RNA. These results will help better predict internal loops that are larger, pyrimidine-rich, and occur within viral structures such as internal ribosome entry sites.


Asunto(s)
Pirimidinas/química , ARN Viral/química , Termodinámica , Emparejamiento Base , Citosina/química , Bases de Datos de Ácidos Nucleicos , Conformación de Ácido Nucleico , Uracilo/química
5.
BMC Psychiatry ; 19(1): 232, 2019 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-31357958

RESUMEN

BACKGROUND: Postpartum depression was associated with maternal suffering and diminished functioning, increased risk of marital conflict as well as adverse child outcomes. Perceived social support during pregnancy was associated with postpartum depression among women. However, its causal relationship remains unclear. Therefore, we prospectively evaluate the association between perceived social support during early pregnancy and postpartum depressive symptoms. METHODS: We prospectively examined whether perceived social support during early pregnancy affected depressive symptoms at 6 weeks postpartum in a cohort of 3310 women. Perceived social support and postpartum depression were assessed by ENRICHD Social Support Instrument (ESSI) and the postpartum Edinburgh Postpartum Depression Scale (EPDS), respectively. Prevalence of postpartum depressive symptoms was 11.4% (EPDS cutoff≥10). As a test of heterogeneity of association in subpopulations, logistic regression models were performed to analyze the association between social support and postpartum depressive symptoms in strata which were defined by the potential confounder candidates. After multiple imputation, multivariable logistic regression was performed to assess the effect of social support on postpartum symptoms in individual items and total score. Two models were built. Model I adjusted for the variables associated with social support or postpartum depression and changed the association estimates by ≥10%. Model II adjusted for all variables that may be related to social support or postpartum depression. RESULTS: Significant associations between low perceived social support and postpartum depressive symptoms was found(Model I odds ratio: 1.63, 95% confidence interval: 1.15, 2.30; Model II odds ratio: 1.77, 95% confidence interval: 1.24-2.52). Stratified analyses showed that there was little evidence of heterogeneity of association in subpopulations by basic characteristics of participants. CONCLUSIONS: These findings suggest that early intervention may be able to help protect against depression symptoms at 6 weeks postpartum.


Asunto(s)
Depresión Posparto/epidemiología , Atención Prenatal/psicología , Apoyo Social , Adulto , Depresión Posparto/psicología , Femenino , Humanos , Modelos Logísticos , Oportunidad Relativa , Percepción , Periodo Posparto/psicología , Embarazo , Prevalencia , Estudios Prospectivos , Escalas de Valoración Psiquiátrica
6.
J Nanobiotechnology ; 13: 32, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25929281

RESUMEN

BACKGROUND: Ceragenins, synthetic mimics of endogenous antibacterial peptides, are promising candidate antimicrobial agents. However, in some settings their strong bactericidal activity is associated with toxicity towards host cells. To modulate ceragenin CSA-13 antibacterial activity and biocompatibility, CSA-13-coated magnetic nanoparticles (MNP-CSA-13) were synthesized. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to characterize MNP-CSA-13 physicochemical properties. Bactericidal action and ability of these new compounds to prevent Pseudomonas. aeruginosa biofilm formation were assessed using a bacteria killing assay and crystal violet staining, respectively. Release of hemoglobin from human red blood cells was measured to evaluate MNP-CSA-13 hemolytic activity. In addition, we used surface activity measurements to monitor CSA-13 release from the MNP shell. Zeta potentials of P. aeruginosa cells and MNP-CSA-13 were determined to assess the interactions between the bacteria and nanoparticles. Morphology of P. aeruginosa subjected to MNP-CSA-13 treatment was evaluated using atomic force microscopy (AFM) to determine structural changes indicative of bactericidal activity. RESULTS: Our studies revealed that the MNP-CSA-13 nanosystem is stable and may be used as a pH control system to release CSA-13. MNP-CSA-13 exhibits strong antibacterial activity, and the ability to prevent bacteria biofilm formation in different body fluids. Additionally, a significant decrease in CSA-13 hemolytic activity was observed when the molecule was immobilized on the nanoparticle surface. CONCLUSION: Our results demonstrate that CSA-13 retains bactericidal activity when immobilized on a MNP while biocompatibility increases when CSA-13 is covalently attached to the nanoparticle.


Asunto(s)
Antibacterianos/farmacología , Nanopartículas de Magnetita , Esteroides/química , Antibacterianos/efectos adversos , Antibacterianos/química , Biopelículas/efectos de los fármacos , Rastreo Diferencial de Calorimetría , Eritrocitos/efectos de los fármacos , Humanos , Nanopartículas de Magnetita/química , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Transmisión , Pseudomonas aeruginosa/efectos de los fármacos , Espectroscopía Infrarroja por Transformada de Fourier , Esteroides/farmacología , Termogravimetría
7.
Sensors (Basel) ; 15(8): 17895-915, 2015 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-26213929

RESUMEN

An autonomous remote clock control system is proposed to provide time synchronization and frequency syntonization for satellite to satellite or ground to satellite time transfer, with the system comprising on-board voltage controlled oven controlled crystal oscillators (VC-OCXOs) that are disciplined to a remote master atomic clock or oscillator. The synchronization loop aims to provide autonomous operation over extended periods, be widely applicable to a variety of scenarios and robust. A new architecture comprising the use of frequency division duplex (FDD), synchronous time division (STDD) duplex and code division multiple access (CDMA) with a centralized topology is employed. This new design utilizes dual one-way ranging methods to precisely measure the clock error, adopts least square (LS) methods to predict the clock error and employs a third-order phase lock loop (PLL) to generate the voltage control signal. A general functional model for this system is proposed and the error sources and delays that affect the time synchronization are discussed. Related algorithms for estimating and correcting these errors are also proposed. The performance of the proposed system is simulated and guidance for selecting the clock is provided.

8.
Sci Total Environ ; 946: 174204, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38914342

RESUMEN

Film mulching has been extensively used to improve agricultural production in arid regions of China. However, without sufficient mulch film recovery, large amounts of residual film accumulated in the farmland, which would affect crop yield and water use efficiency (WUE). In order to comprehensively analyze the effects of residual film on crop yield and WUE, and clarify its influencing mechanism, present study adopted a meta-analysis to systematically evaluate the impacts of residual film on soil physicochemical properties, crop root growth, yield, and WUE. The results showed that residual film significantly increased soil bulk density and the soil moisture content in 0-20 cm soil layer, but decreased soil porosity, soil organic matter, soil total nitrogen content, and soil moisture content in >20 cm soil layer, especially when residual film amount was >400 kg ha-1. Residual film significantly reduced crop root dry weight, root length, root diameter, root volume and root surface area. Generally, crop yield and WUE decreased with the increase of residual film amount; and crop yield was reduced by about 14.00 % when the residual film amount increased by 1000 kg ha-1. In average, crop yield and WUE under film residual condition were significantly decreased by 13.46 % and 9.21 %, respectively. The negative effects of residual film on root growth, yield and WUE were greater for cash crops (cotton, tomato and potato) than for cereal crops (wheat, maize). The structural equation model indicated that residual film generated indirect negative effects on crop yield and WUE by directly affecting soil physicochemical properties and crop root growth, with the standard path coefficients of -0.302 and - 0.217, respectively. The results would provide a theoretical basis for reducing residual film pollution on farmland and promoting the green and sustainable development of agriculture.

9.
Biomol Biomed ; 2024 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-38498300

RESUMEN

This study investigates the clinical features and therapeutic outcomes of otitis media with effusion (OME) in adults following infection with the Omicron variant of coronavirus disease 2019 (COVID-19), in the context of China ending its "Zero-COVID-19" policy. Conducted as a multicenter, retrospective analysis at two medical institutions in Eastern China from December 2022 to February 2023, the study included patients with confirmed Omicron infection who were diagnosed with OME within two months, adhering to guidelines from the American Academy of Otolaryngology-Head and Neck Surgery Foundation (AAO-HNSF). Data on demographics, time from infection to OME manifestation, associated symptoms, and treatment outcomes were collected. Among 68 patients (73 affected ears) with OME post-Omicron infection, common symptoms included cough and nasal obstruction (69.1%). All reported ear fullness, with 86.8% experiencing hearing loss. Tympanic bullae were observed in 72.6% during otoscopy, and most tympanometry results showed a B-type tympanogram (80.0%). An integrated treatment strategy led to an 83.6% cure rate, although 8.2% experienced relapse within 2-3 months. Our findings highlight OME as a prevalent ear complication associated with COVID-19 during the Omicron pandemic, underscoring the necessity for further investigation into its complexities. While the integrated treatment approach proved effective, the 8.2% post-treatment recurrence rate underscores the importance of ongoing monitoring and signals an urgent need for more comprehensive research.

10.
Sci Rep ; 14(1): 6072, 2024 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-38480826

RESUMEN

Blood transfusions from convalescent Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infected patients could be used to treat patients with severe infections or immunocompromised patients. However, it is necessary to select the optimal donors to maximize the utilization of resources. In this study, we investigated the associations among body mass index (BMI), tobacco smoking, exercise frequency and duration, and alcohol consumption with the SARS-CoV-2 immunoglobulin-G (IgG) antibody titer levels with in the Chinese convalescent blood donor population. Here we show that BMI, smoking habits, and exercise frequency appear to be predictive factors for IgG levels in convalescent male blood donors. However, these variables were not observed as predictive of IgG levels in female convalescent blood donors. The findings could be used to optimize the screening for potential blood donors to treat immunocompromised or severely ill COVID-19 patients.


Asunto(s)
COVID-19 , Humanos , Masculino , Femenino , SARS-CoV-2 , Donantes de Sangre , Estudios Transversales , Inmunización Pasiva , Sueroterapia para COVID-19 , Anticuerpos Antivirales , Inmunoglobulina G , China
11.
Endocr Pathol ; 34(3): 323-332, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37572175

RESUMEN

Reliable preoperative diagnosis of thyroid nodules remained challenging because of the inconclusiveness of fine-needle aspiration (FNA) cytology. In the present study, 583 formalin-fixed paraffin embedded (FFPE) thyroid nodule tissues and 161 FNA specimens were enrolled retrospectively. Then BRAF V600E, EZH1 Q571R, SPOP P94R, and ZNF148 mutations among these samples were identified using Sanger sequencing. Based on this four-gene genomic classifier, we proposed a two-step modality to diagnose thyroid nodules to differentiate benign and malignant thyroid nodules. In the FFPE group, thyroid cancers were effectively diagnosed in 37.7% (220/583) of neoplasms by the primary BRAF V600E testing, and 15.7% (57/363) of thyroid nodules could be further determined as benign by subsequent EZH1 Q571R, SPOP P94R, and ZNF148 (we called them "ESZ") mutation testing. In the FNA group, 161 BRAF wild-type specimens were classified according to The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC). A total of 7 mutated samples fell within Bethesda categories III-IV, and the mutation rate of "ESZ" in Bethesda III-IV categories was 8.4%. The two-step genomic classifier could further improve thyroid nodule diagnosis, which may inform more optimal patient management.


Asunto(s)
Neoplasias de la Tiroides , Nódulo Tiroideo , Humanos , Nódulo Tiroideo/diagnóstico , Nódulo Tiroideo/genética , Nódulo Tiroideo/patología , Proteínas Proto-Oncogénicas B-raf/genética , Estudios Retrospectivos , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Mutación , Análisis Mutacional de ADN , Complejo Represivo Polycomb 2/genética , Proteínas de Unión al ADN/genética , Factores de Transcripción/genética
12.
Front Immunol ; 14: 1191479, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37388736

RESUMEN

Background: Demographic information has been shown to help predict high antibody titers of COVID-19 convalescent plasma (CCP) in CCP donors. However, there is no research on the Chinese population and little evidence on whole-blood donors. Therefore, we aimed to investigate these associations among Chinese blood donors after SARS-CoV-2 infection. Methods: In this cross-sectional study, 5,064 qualified blood donors with confirmed or suspected SARS-CoV-2 infection completed a self-reported questionnaire and underwent tests of SARS-CoV-2 Immunoglobulin G (IgG) antibody and ABO blood type. Logistic regression models were used to calculate odds ratios (ORs) for high SARS-CoV-2 IgG titers according to each factor. Results: Totally, 1,799 participants (with SARS-CoV-2 IgG titers≥1:160) had high-titer CCPs. Multivariable analysis showed that a 10-year increment in age and earlier donation were associated with higher odds of high-titer CCP, while medical personnel was associated with lower odds. The ORs (95% CIs) of high-titer CCP were 1.17 (1.10-1.23, p< 0.001) and 1.41 (1.25-1.58, p< 0.001) for each 10-year increment in age and earlier donation, respectively. The OR of high-titer CCP was 0.75 (0.60-0.95, p = 0.02) for medical personnel. Female early donors were associated with increased odds of high-titer CCP, but this association was insignificant for later donors. Donating after 8 weeks from the onset was associated with decreased odds of having high-titer CCP compared to donating within 8 weeks from the onset, and the HR was 0.38 (95% CI: 0.22-0.64, p <0.001). There was no significant association between ABO blood type or race and the odds of high-titer CCP. Discussion: Older age, earlier donation, female early donors, and non-medical-related occupations are promising predictors of high-titer CCP in Chinese blood donors. Our findings highlight the importance of CCP screening at the early stage of the pandemic.


Asunto(s)
Antígenos de Grupos Sanguíneos , COVID-19 , Femenino , Humanos , Donantes de Sangre , Estudios Transversales , SARS-CoV-2 , Sueroterapia para COVID-19 , China/epidemiología , Anticuerpos Antivirales , Inmunoglobulina G
14.
J Biol Chem ; 286(16): 14419-26, 2011 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-21349846

RESUMEN

Prohead RNA (pRNA) is an essential component of the self-assembling ϕ29 bacteriophage DNA packaging motor. Different related species of bacteriophage share only 12% similarity in pRNA sequences. The secondary structure for pRNA is conserved, however. In this study, we present evidence for self-assembly in different pRNA sequences and new measurements of the energetics for the quaternary interactions in pRNA dimers and trimers. The energetics for self-assembly in different pRNA sequences are similar despite very different sequences in the loop-loop interactions. The architecture surrounding the interlocking loops contributes to the stability of the pRNA quaternary interactions, and sequence variation outside the interlocking loops may counterbalance the changes in the loop sequences. Thus, the evolutionary divergence of pRNA sequences maintains not only conservation of function and secondary structure but also stabilities of quaternary interactions. The self-assembly of pRNA can be fine-tuned with variations in magnesium chloride, sodium chloride, temperature, and concentration. The ability to control pRNA self-assembly holds promise for the development of nanoparticle therapeutic applications for this biological molecule. The pRNA system is well suited for future studies to further understand the energetics of RNA tertiary and quaternary interactions, which can provide insight into larger biological assemblies such as viruses and biomolecular motors.


Asunto(s)
ARN Viral/química , Secuencia de Bases , Dicroismo Circular , Dimerización , Cloruro de Magnesio/farmacología , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Nucleótidos/química , Unión Proteica , Estructura Secundaria de Proteína , Cloruro de Sodio/farmacología , Temperatura , Ultracentrifugación
15.
J Am Chem Soc ; 134(49): 20060-9, 2012 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-22934853

RESUMEN

The structure and stability of long telomeric DNAs, (T(2)AG(3))(n) (n = 4-20), were studied under dilute and molecular crowding conditions in the presence of Na(+) and K(+). Structural analysis showed that the long telomeric DNAs formed intramolecular G-quadruplexes under all conditions. In the presence of Na(+), the telomeric DNAs formed an antiparallel G-quadruplex under both dilute and molecular crowding conditions. However, in the presence of K(+), molecular crowding induced a conformational change from mixed to parallel. These results are consistent with numerous structural studies for G-quadruplex units under molecular crowding conditions. Thermodynamic analysis showed that G-quadruplexes under the molecular crowding conditions were obviously more stable than under dilute condition. Interestingly, this stabilization effect of molecular crowding was reduced for the longer telomeric DNAs, indicating that the G-quadruplex structure of long telomeric DNAs is not as stable under molecular crowding conditions, as implied from the large stabilization of isolated G-quadruplex units as previously reported. Moreover, a hydration study revealed that upon structure folding, the interior of a G-quadruplex unit was dehydrated, whereas the linker between two units was more hydrated. It is thus possible to propose that the linkers between G-quadruplex units are ordered structures but not random coils, which could have an important influence on the stability of the entire structure of long telomeric DNAs. These results are significant to elucidate the biological characteristics of telomeres, and can aid in the rational design of ligands and drugs targeting the telomere and related proteins.


Asunto(s)
ADN/química , Telómero/química , Conformación de Ácido Nucleico , Potasio/química , Sodio/química , Termodinámica
16.
Sci Total Environ ; 835: 155507, 2022 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-35483464

RESUMEN

Soil is the largest terrestrial carbon pool, and adsorption of soil organic matter (SOM) by ferrihydrite is an essential geochemical process for preservation of organic carbon in soil. Freshly formed gel-like ferrihydrite and seasonally dried dense ferrihydrite are two typical morphologies of ferrihydrite in soil. However, the differences in SOM adsorption by gel-like ferrihydrite and dense ferrihydrite and the underlying mechanisms are unknown. In this study, adsorption of eight SOM or SOM-like compounds by gel-like ferrihydrite and dense ferrihydrite were compared. It was observed that the adsorption capacity of SOM by gel-like ferrihydrite (e.g., 304 mg C/g) was two orders of magnitude higher than that by dense ferrihydrite (e.g., 3.44 mg C/g). SOM adsorbed by the nanosized gel-like ferrihydrite could be mainly attributed to the heteroaggregation, confirmed by not only the TEM images but also the positive linear correlation between adsorption capacity and molecular weight of SOM. However, SOM adsorbed by the microsized dense ferrihydrite should be attributed to the pore-filling adsorption with molecular sieve effects, confirmed by the negative linear correlation between adsorption capacity and molecular weight of SOM. The obtained results could provide a new insight to understand the preservation of organic carbon by ferrihydrite in soil.


Asunto(s)
Contaminantes del Suelo , Suelo , Adsorción , Carbono , Compuestos Férricos , Suelo/química , Contaminantes del Suelo/análisis
17.
Foods ; 11(16)2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-36010455

RESUMEN

Malolactic fermentation (MLF) converts malic acid into lactic acid by lactic acid bacteria (LAB). MLF may affect potential wine quality impact as global warming intensifies, and the alcohol in the wine increases, which threatens MLF. Lactiplantibacillus plantarum is considered a new generation of MLF starter because of the ability of high ethanol tolerance and good enological characteristics. In this research, 132 LAB strains were isolated from the eastern foothills of Helan Mountain in Ningxia, China. Twenty-one higher ethanol tolerance isolates were obtained by 15% (v/v) ethanol preliminary screening. They were identified by 16S rRNA sequencing and differentiated by randomly amplified polymorphic DNA (RAPD). Stress factors include ethanol, pH, and SO2, and the combination of stresses was used to screen stress-tolerance strains. ß-D-glucosidase activity, MLF performance, and biogenic amine content were tested to evaluate the enological characteristics. GC-MS detected the volatile components of the wine after MLF. The results showed that twenty strains were identified as L. plantarum, and one strain was Lentilactobacillus hilgardii. Especially, the strains of A7, A18, A23, A50, and B28 showed strong resistance to high ethanol, low pH, and high SO2. A7, A50, and B28 showed better ß-D-glucosidase activity and thus were inoculated into cabernet sauvignon wines whose ethanol content was 14.75% (v/v) to proceed MLF. A7 finished MLF in 36 d, while the control strains Oenococcus oeni 31-DH and L. plantarum BV-S2 finished MLF in 24 d and 28 d, respectively. Nevertheless, A50 and B28 did not finish MLF in 36 d. The data showed that A7 brought a more volatile aroma than control. Notably, the esters and terpenes in the wine increased. These results demonstrated the potential applicability of L. plantarum A7 as a new MLF starter culture, especially for high-ethanol wines.

18.
Foods ; 11(18)2022 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-36140932

RESUMEN

Grape volatile compounds directly determine the aroma quality of wines. Although the aroma profile of grapes evolved greatly at different maturity stages, there were less considerations for aroma status when determining grape harvest time. In the present study, several maturation indicators, namely, sugars/acids ratio, free volatile compounds, bound volatile compounds and IBMP (3-isobutyl-2-methoxypyrazine) content were monitored in four red wine grape varieties (Vitis vinifera L. cv Cabernet Sauvignon, Cabernet Gernischet, Cabernet Franc and Merlot) near harvest time (42 days) in Ningxia, China. The results showed that the highest sugars/acids ratio was reached on day 21 and day 28 for Merlot and the other three varieties, respectively. For both free and bound volatile compounds, the content of carbonyl compounds decreased continuously in the process of ripening. The contents of free alcohols, esters and terpenes increased in the ripening stage and decreased in the stage of over-ripening. The accumulation of favorable bound aroma compounds peaked at day 35. The content of IBMP presenting a green smell in all four varieties descended continuously and kept steady from day 28. Therefore, the present findings revealed that the best aroma maturity time of four studied grape varieties was later than the sugars/acids ratio in Ningxia region. Aroma maturity should be taken into account during harvest time determination.

19.
Front Public Health ; 10: 879410, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35664106

RESUMEN

Purpose: This study aimed to evaluate the effectiveness of smartphone otoscope telemedicine in the rural medical consortium in East China in the COVID-19 era. Methods: This prospective study was conducted within a rural medical consortium that provides health care services by integrating medical resources in the same area. When a patient visited primary health care (PHC) for ear diseases, the PHC provider used a smartphone otoscope to examine the patient's external ear canal and eardrum, and then sent photos or videos of the patient's ear to the otolaryngologist at the lead hospital via WeChat group. The otolaryngologist provided remote diagnosis and management recommendations to the PHC provider. The following data were recorded: age and gender, outpatient diagnosis, disease duration, sides, duration of treatment, telemedicine visits, treatment outcomes, patient satisfaction, and PHC providers' self-evaluation score. Results: A total of 83 patients were included in the study, including 43 males and 40 females, with a mean age of 44.6 ± 19.7 years (range 3-83 years). The duration of treatment for these patients was 14.0 (7,14) days. PHC visits were 2.2 ± 1.1 times (range: 1-7 times). Telemedicine visits ranged from 1 to 5, with a mean of 1.8 ± 0.9. Among of patients, 62 (74.7%) were cured, 21 (25.3%) improved, and 0 (0%) were ineffective. Sixty-five patients (78.3%) were very satisfied, 16 (19.3%) patients were somewhat satisfied, and two patients (2.4%) were dissatisfied. Based on the self-reported helpfulness, the primary health care providers assessed telemedicine as very helpful (n = 63, 75.9%), helpful (n = 20, 24.1%), and unhelpful (n = 0, 0%). Conclusions: Smartphone otoscope telemedicine in the medical consortium can effectively improve the ability of rural PHC providers to diagnose and treat ear diseases, save time and costs for patients, and improve patient satisfaction.


Asunto(s)
COVID-19 , Enfermedades del Oído , Telemedicina , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/epidemiología , Niño , Preescolar , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Otoscopios , Estudios Prospectivos , Teléfono Inteligente , Adulto Joven
20.
J Oleo Sci ; 71(2): 247-255, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35110467

RESUMEN

Disorganization and breakdown of extracellular matrix proteins like fibronectin, collagen, and elastin are key characteristics of skin aging due to the increased activation of important proteolytic enzymes like elastases and collagenase enzymes. Also, inhibition of their enzymatic activities by natural molecules might be a promising factor to prevent extrinsic skin aging. All chemicals were obtained from Sigma-Aldrich unless otherwise stated. The assay employed was based on spectrophotometric methods reported in the literature. The collagenase and elastase inhibition assays of some phenolic compounds were performed according to the previous studies. These compounds showed excellent to good inhibitory activities of vulpinic acid against studied these enzymes with IC50 values of 195.36 µM for collagenase and 25.24 µM for elastase. The molecular docking calculations were conducted to investigate the chemical and biological activity of vulpinic acid and usnic acid against collagenase and elastase. The results indicated that these two compounds can interact with the essential residues of the enzymes and affect their activities. The calculations of binding free energies were also performed to obtain more details about the characteristics and free energies of the ligand-enzyme complexes. Additionally, both compounds exhibited the most potent inhibition in the three lung cancer cells, with an IC50 value of 21-68 µM, indicating that vulpinic acid is more potent than Doxorubicin, which exhibited an IC50 value of 21-29 µM.


Asunto(s)
Antineoplásicos , Benzofuranos/farmacología , Colagenasas/metabolismo , Furanos/farmacología , Gerociencia , Neoplasias Pulmonares/patología , Elastasa Pancreática/metabolismo , Fenilacetatos/farmacología , Envejecimiento de la Piel/efectos de los fármacos , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Proteínas de la Matriz Extracelular/metabolismo , Humanos , Modelos Moleculares , Envejecimiento de la Piel/fisiología
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