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1.
Antimicrob Agents Chemother ; 68(5): e0161523, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38526047

RESUMEN

AT-752 is a novel guanosine nucleotide prodrug inhibitor of the dengue virus (DENV) polymerase with sub-micromolar, pan-serotype antiviral activity. This phase 1, double-blind, placebo-controlled, first-in-human study evaluated the safety, tolerability, and pharmacokinetics of ascending single and multiple oral doses of AT-752 in healthy subjects. AT-752 was well tolerated when administered as a single dose up to 1,500 mg or when administered as multiple doses up to 750 mg three times daily (TID). No serious adverse events occurred, and the majority of treatment-emergent adverse events were mild in severity and resolved by the end of the study. In those receiving single ascending doses of AT-752, no pharmacokinetic sensitivity was observed in Asian subjects, and no food effect was observed. Plasma exposure of the guanosine nucleoside metabolite AT-273, the surrogate of the active triphosphate metabolite of the drug, increased with increasing dose levels of AT-752 and exhibited a long half-life of approximately 15-25 h. Administration of AT-752 750 mg TID led to a rapid increase in plasma levels of AT-273 exceeding the target in vitro 90% effective concentration (EC90) of 0.64 µM in inhibiting DENV replication, and maintained this level over the treatment period. The favorable safety and pharmacokinetic results support the evaluation of AT-752 as an antiviral for the treatment of dengue in future clinical studies.Registered at ClinicalTrials.gov (NCT04722627).


Asunto(s)
Antivirales , Dengue , Nucleótidos de Guanina , Profármacos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Antivirales/efectos adversos , Antivirales/farmacocinética , Dengue/tratamiento farmacológico , Método Doble Ciego , Semivida , Profármacos/efectos adversos , Profármacos/farmacocinética , Adolescente
2.
J Antimicrob Chemother ; 79(6): 1423-1431, 2024 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-38708557

RESUMEN

BACKGROUND: Bemnifosbuvir (AT-527) is a novel oral guanosine nucleotide antiviral drug for the treatment of persons with COVID-19. Direct assessment of drug disposition in the lungs, via bronchoalveolar lavage, is necessary to ensure antiviral drug levels at the primary site of SARS-CoV-2 infection are achieved. OBJECTIVES: This Phase 1 study in healthy subjects aimed to assess the bronchopulmonary pharmacokinetics, safety and tolerability of repeated doses of bemnifosbuvir. METHODS: A total of 24 subjects were assigned to receive bemnifosbuvir twice daily at doses of 275, 550 or 825 mg for up to 3.5 days. RESULTS: AT-511, the free base of bemnifosbuvir, was largely eliminated from the plasma within 6 h post dose in all dosing groups. Antiviral drug levels of bemnifosbuvir were consistently achieved in the lungs with bemnifosbuvir 550 mg twice daily. The mean level of the guanosine nucleoside metabolite AT-273, the surrogate of the active triphosphate metabolite of the drug, measured in the epithelial lining fluid of the lungs was 0.62 µM at 4-5 h post dose. This exceeded the target in vitro 90% effective concentration (EC90) of 0.5 µM for antiviral drug exposure against SARS-CoV-2 replication in human airway epithelial cells. Bemnifosbuvir was well tolerated across all doses tested, and most treatment-emergent adverse events reported were mild in severity and resolved. CONCLUSIONS: The favourable pharmacokinetics and safety profile of bemnifosbuvir demonstrates its potential as an oral antiviral treatment for COVID-19, with 550 mg bemnifosbuvir twice daily currently under further clinical evaluation in persons with COVID-19.


Asunto(s)
Antivirales , Tratamiento Farmacológico de COVID-19 , Profármacos , SARS-CoV-2 , Humanos , Antivirales/farmacocinética , Antivirales/administración & dosificación , Antivirales/efectos adversos , Masculino , Adulto , Profármacos/farmacocinética , Profármacos/administración & dosificación , Femenino , SARS-CoV-2/efectos de los fármacos , Persona de Mediana Edad , Administración Oral , COVID-19 , Adulto Joven , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/virología , Voluntarios Sanos , Guanosina/análogos & derivados , Guanosina/farmacocinética , Guanosina/administración & dosificación
3.
J Nanobiotechnology ; 22(1): 376, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38926780

RESUMEN

Tissue regeneration technology has been rapidly developed and widely applied in tissue engineering and repair. Compared with traditional approaches like surgical treatment, the rising gene therapy is able to have a durable effect on tissue regeneration, such as impaired bone regeneration, articular cartilage repair and cancer-resected tissue repair. Gene therapy can also facilitate the production of in situ therapeutic factors, thus minimizing the diffusion or loss of gene complexes and enabling spatiotemporally controlled release of gene products for tissue regeneration. Among different gene delivery vectors and supportive gene-activated matrices, advanced gene/drug nanocarriers attract exceptional attraction due to their tunable physiochemical properties, as well as excellent adaptive performance in gene therapy for tissue regeneration, such as bone, cartilage, blood vessel, nerve and cancer-resected tissue repair. This paper reviews the recent advances on nonviral-mediated gene delivery systems with an emphasis on the important role of advanced nanocarriers in gene therapy and tissue regeneration.


Asunto(s)
Técnicas de Transferencia de Gen , Terapia Genética , Regeneración , Ingeniería de Tejidos , Andamios del Tejido , Humanos , Animales , Terapia Genética/métodos , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Nanopartículas/química , Portadores de Fármacos/química , Vectores Genéticos
4.
J Environ Manage ; 367: 122087, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39111001

RESUMEN

With the rapid expansion of human activities, there has been a significant increase in the release of volatile organic compounds (VOCs) from factories and interior decoration materials, posing a substantial risk to the surrounding ecosystem and human health. Photocatalysis technology based on semiconductors has emerged as a promising solution for mitigating atmospheric pollution and indoor air quality concerns. However, single semiconductors encounter several challenges when it comes to VOC photodegradation, including issues like the weak adsorption capacity for VOC molecules, insufficient surface-active sites, and limited light utilization. In recent decades, carbon-based materials have gained considerable interest in photodegrading VOCs owing to their strong adsorption capacity, electrical conductivity, broad light absorption range, and tunable surface characteristics. The incorporation of carbon materials can enhance the photodegradation efficiency of VOCs by facilitating the transfer of VOCs from the ambient air to the surface of the photocatalysts, increasing the number of active surface sites, expanding the light absorption region, and promoting the separation of charge carriers. This review provides a comprehensive overview of the applications of carbon materials with different dimensions in enhancing the performance of semiconductors for the photocatalytic degradation of VOCs. Based on the fundamental principles of photocatalytic VOC degradation, this review explores the factors influencing the degradation performance of catalysts and elucidates the degradation mechanisms. Moreover, it summarizes a range of synthesis approaches for carbon-based photocatalysts, discussing the multiple roles played by carbon materials in these processes. In conclusion, the review offers insights into the current state of carbon-based photocatalysts and outlines the existing challenges. It also provides a perspective on the future development of these materials, highlighting the need for continued research and innovation in this field.


Asunto(s)
Carbono , Compuestos Orgánicos Volátiles , Compuestos Orgánicos Volátiles/química , Catálisis , Carbono/química , Adsorción , Fotólisis
5.
Chembiochem ; 24(7): e202200719, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-36734180

RESUMEN

Optically active epoxides play important roles in pharmaceutical, agricultural and fine chemical syntheses. There are many chiral medications with pharmacodynamic activity in nature that can be synthesized by chiral epoxides. In recent years, researchers have developed a variety of biocatalysts for the asymmetric epoxidation of alkenes, which use oxygen or hydrogen peroxide as eco-friendly and low-cost oxidants, to provide better chemo-, regio- and stereoselectivity under moderate reaction conditions. In this paper, the advances, opportunities and challenges of the asymmetric epoxidation of unactive alkenes by biocatalyst are reviewed.


Asunto(s)
Alquenos , Oxidantes , Catálisis , Peróxido de Hidrógeno , Compuestos Epoxi , Estereoisomerismo
6.
Respir Res ; 23(1): 182, 2022 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-35831898

RESUMEN

OBJECTIVE: To establish the predicted value of pulmonary function determined by impulse oscillometry (IOS) in children (4-17 years old) in China. METHODS: A total of 6270 healthy children aged 4-17 years in China were included. The Master Screen IOS pulmonary function device (Jaeger Co, Germany) was used to detect the respiratory impedance (Zrs), resonant frequency (Fres), respiratory system resistance (Rrs) and respiratory system reactance (Xrs) at various oscillation frequencies, and the indices above were analysed. Stepwise multivariate regression was used to establish the regression equation of related parameters of IOS in different sexes, ages, height, and weight. RESULTS: The differences in the main IOS parameters between different age stages were statistically significant regardless of sex (P < 0.05). The stepwise multivariate regression analysis showed that IOS parameters were related to height, age, and weight, and most IOS parameters were most closely related to height (the absolute value of the regression coefficient was the largest). With increasing age and height, the values of Z5, R5, R20, R5-R20, and Fres decreased, while the value of X5 increased. Through height, age, and weight, we obtained the normal predicted values equation of children's IOS parameters. Compared with the other reference equations, our reference equation is more suitable for Chinese children. CONCLUSIONS: The study revealed the reference values of IOS parameters in healthy Chinese children. In the evaluation of results for lung function measurements, this predicted value equation is more consistent with the characteristics of Chinese children than other reference equations. CLINICAL TRIAL: ChiCTR: 1800019029.


Asunto(s)
Pulmón , Adolescente , Niño , Preescolar , China , Humanos , Oscilometría/métodos , Valores de Referencia , Pruebas de Función Respiratoria/métodos , Espirometría
7.
Environ Res ; 206: 112275, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-34710437

RESUMEN

Exposure to fine particulate matter (PM2.5) and ozone (O3) may lead to inflammation and oxidative damage in the oral cavity, which is hypothesized to contribute to the worsening of airway inflammation and asthma symptoms. In this panel study of 43 asthmatic children aged 5-13 years old, each child had 4 clinic visits with a 2-week interval between two consecutive visits. At each visit, saliva samples were collected and subsequently analyzed for interleukin 6 (IL-6) and eosinophil cationic protein (ECP) as biomarkers of inflammation and malondialdehyde (MDA) as a biomarker of oxidative stress in the oral cavity. At each visit, children were measured for fractional exhaled nitric oxide (FeNO) as a marker of pulmonary inflammation. Asthma symptoms of these children were measured using the Childhood Asthma Control Test (C-ACT). We found that an interquartile range (IQR) increase in 24-h average personal exposure to PM2.5 measured 1 and 2 days prior was associated with increased salivary IL-6 concentration by 3.0% (95%CI: 0.2%-6.0%) and 4.2% (0.7%-8.0%), respectively. However, we did not find a clear association between personal O3 exposure and any of the salivary biomarkers, except for a negative association between salivary MDA and O3 exposure measured 1 day prior. An IQR increase in salivary IL-6 concentration was associated with significantly increased FeNO by 28.8% (4.3%-53.4%). In addition, we found that increasing salivary IL-6 concentrations were associated with decreased individual and total C-ACT scores, indicating the worsening of asthma symptoms. We estimated that 13.2%-22.2% of the associations of PM2.5 exposure measured 1 day prior with FeNO and C-ACT scores were mediated by salivary IL-6. These findings suggest that the induction of inflammation in the oral cavity may have played a role in linking air pollution exposure with the worsening of airway inflammation and asthma symptoms.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Asma , Neumonía , Adolescente , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Contaminación del Aire/análisis , Asma/inducido químicamente , Asma/metabolismo , Niño , Preescolar , Exposición a Riesgos Ambientales/efectos adversos , Humanos , Inflamación/inducido químicamente , Boca/química , Boca/metabolismo , Material Particulado/análisis , Material Particulado/toxicidad
8.
Chirality ; 34(7): 1019-1034, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35521642

RESUMEN

A readily available chiral cyclohexanediamine-derived bifunctional tertiary amine-squaramide catalyst is more effective for the asymmetric dearomative 1,3-dipolar cycloaddition of 2-nitrobenzofurans and N-2,2,2-trifluoroethylisatin ketimines. A range of structurally diverse spiro-fused polyheterocyclic compounds containing oxindole, pyrrolidine, and hydrobenzofuran motifs were smoothly obtained in excellent results (up to 99% yield, >20:1 dr in all cases and up to 99% ee). This method features high efficiency, mild reaction conditions, exquisite asymmetric induction, wide functional group tolerance, great potential for scale-up synthesis, and attractive product diversification.


Asunto(s)
Iminas , Compuestos de Espiro , Benzofuranos , Reacción de Cicloadición , Nitrilos , Estereoisomerismo
9.
J Obstet Gynaecol ; 42(7): 2813-2817, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35980725

RESUMEN

A total of 179 normal full-term pregnant women and their newborns were randomly selected. Umbilical venous blood was extracted after the delivery, and the serum level of 25(OH)D3 was measured. Forty 2 days, 3 months, 6 months, and one year after the birth to be asked about the occurrence and development of infant eczema. Thirteen cases were lost to follow-up. The median concentration of 25(OH)D3 in the cord blood was 25.40 ng/mL. Thirty eight cases (22.9%) were vitamin D deficient (<20 ng/mL), 77 cases (46.4%) were vitamin D insufficient (20-30 ng/mL), and 51 cases (30.7%) were vitamin D sufficient (≥30 ng/mL). The incidence of eczema in the umbilical cord blood vitamin D sufficient group was lower than that in the deficient and insufficient groups (p < .05). Sufficient umbilical cord blood vitamin D levels are associated with a lower incidence of eczema in infants up to one year of age. IMPACT STATEMENTWhat is already known on this subject? A number of studies have suggested that vitamin D levels in early life are related to the occurrence of allergic diseases, but the conclusions are not uniform.What do the results of this study add? The rate of sufficient umbilical cord blood vitamin D was low in the Songjiang area of Shanghai. Sufficient umbilical cord blood vitamin D levels (≥30 ng/mL) are associated with a lower incidence of eczema in infants up to 1 year of age.What are the implications of these findings for clinical practice and/or further research? At present, the dose of vitamin D for pregnant women at home and abroad is not consistent, so the specific dose of vitamin D for pregnant women to maintain the foetus needs further discussion. It is expected that a reasonable recommended dose can be developed to reduce the risk of allergic diseases in future generations from a primary prevention perspective.


Asunto(s)
Dermatitis Atópica , Eccema , Deficiencia de Vitamina D , Lactante , Recién Nacido , Femenino , Humanos , Embarazo , Vitamina D , Sangre Fetal , China , Vitaminas , Deficiencia de Vitamina D/complicaciones , Deficiencia de Vitamina D/epidemiología , Calcifediol , Eccema/epidemiología , Eccema/etiología
10.
Artículo en Inglés | MEDLINE | ID: mdl-33558299

RESUMEN

The impact of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the causative agent of COVID-19, is global and unprecedented. Although remdesivir has recently been approved by the FDA to treat SARS-CoV-2 infection, no oral antiviral is available for outpatient treatment. AT-527, an orally administered double prodrug of a guanosine nucleotide analog, was previously shown to be highly efficacious and well tolerated in hepatitis C virus (HCV)-infected subjects. Here, we report the potent in vitro activity of AT-511, the free base of AT-527, against several coronaviruses, including SARS-CoV-2. In normal human airway epithelial cells, the concentration of AT-511 required to inhibit replication of SARS-CoV-2 by 90% (EC90) was 0.47 µM, very similar to its EC90 against human coronavirus (HCoV)-229E, HCoV-OC43, and SARS-CoV in Huh-7 cells. Little to no cytotoxicity was observed for AT-511 at concentrations up to 100 µM. Substantial levels of the active triphosphate metabolite AT-9010 were formed in normal human bronchial and nasal epithelial cells incubated with 10 µM AT-511 (698 ± 15 and 236 ± 14 µM, respectively), with a half-life of at least 38 h. Results from steady-state pharmacokinetic and tissue distribution studies of nonhuman primates administered oral doses of AT-527, as well as pharmacokinetic data from subjects given daily oral doses of AT-527, predict that twice daily oral doses of 550 mg AT-527 will produce AT-9010 trough concentrations in human lung that exceed the EC90 observed for the prodrug against SARS-CoV-2 replication. This suggests that AT-527 may be an effective treatment option for COVID-19.


Asunto(s)
Antivirales/farmacología , Tratamiento Farmacológico de COVID-19 , Guanosina Monofosfato/análogos & derivados , Guanosina/farmacología , Fosforamidas/farmacología , Profármacos/farmacología , SARS-CoV-2/efectos de los fármacos , Administración Oral , Animales , COVID-19/virología , Línea Celular , Línea Celular Tumoral , Chlorocebus aethiops , Coronavirus Humano 229E/metabolismo , Coronavirus Humano OC43/metabolismo , Cricetinae , Células Epiteliales/virología , Guanosina Monofosfato/farmacología , Humanos , Pulmón/virología , SARS-CoV-2/metabolismo , Células Vero , Replicación Viral/efectos de los fármacos
11.
Opt Express ; 29(12): 18654-18668, 2021 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-34154118

RESUMEN

Quantum-dot color conversion (QDCC) is a promising technique for next-generation full-color displays, such as QD converted organic light-emitting diodes and micro light-emitting diodes. Although present QDCC research has made some progress on the experimental aspect, the optical model and corresponding mathematical expression that can lay an indispensable foundation for QDCC have not been reported yet. In this paper, we present a theoretical model for precisely describing the complete optical behavior of QDCC, including optical transmission, scattering, absorption, and conversion process. A key parameter of QDCC, called dosage factor (DoF), is defined to quantitatively express the total consumption of QDs that can be calculated as the product of film thickness and QD concentration. Theoretical relations are established between DoF and three key performance indicators of QDCC, namely the light conversion efficiency (LCE), blue light transmittance (BLT), and optical density (OD). The maximum LCE value can be predicted based on this theoretical model, as well as the relationship between the slope of the OD curve and the molar absorption coefficient of blue light. This theoretical model is verified by both simulation and experiment. Results show that the simulation and experimental data highly match the theoretical model, and the goodness of fit reaches higher than 96% for LCE, BLT, and OD. Based on this, the optimal interval of DoF is recommended that provides key guiding significance to the QDCC related experiment.

12.
Environ Sci Technol ; 55(5): 3101-3111, 2021 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-33555874

RESUMEN

Fine particulate matter (PM2.5) with a higher oxidative potential has been thought to be more detrimental to pulmonary health. We aim to investigate the associations between personal exposure to PM2.5 oxidative potential and pulmonary outcomes in asthmatic children. We measured each of the 43 asthmatic children 4 times for airway mechanics, lung function, airway inflammation, and asthma symptom scores. Coupling measured indoor and outdoor concentrations of PM2.5 mass, constituents, and oxidative potential with individual time-activity data, we calculated 24 h average personal exposures 0-3 days prior to a health outcome measurement. We found that increases in daily personal exposure to PM2.5 oxidative potential were significantly associated with increased small, large, and total airway resistance, increased airway impedance, decreased lung function, and worsened scores of individual asthma symptoms and the total symptom score. Among the PM2.5 constituents, organic matters largely of indoor origin contributed the greatest to PM2.5 oxidative potential. Given that the variability in PM2.5 oxidative potential was a stronger driver than PM2.5 mass for the variability in the respiratory health outcomes, it is suggested to reduce PM2.5 oxidative potential, particularly by reducing the organic matter constituent of indoor PM2.5, as a targeted source control strategy in asthma management.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Asma , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Niño , Exposición a Riesgos Ambientales , Monitoreo del Ambiente , Humanos , Estrés Oxidativo , Material Particulado/análisis
13.
Environ Sci Technol ; 54(18): 11405-11413, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32822160

RESUMEN

Fine particulate matter (PM2.5) and ozone (O3) may exert oxidative damage in the nose, which is hypothesized to be associated with worsened asthma symptoms. This study, hence, is to explore whether an oxidative stress biomarker, malondialdehyde (MDA) in the nasal fluid, has the potential to aid personalized asthma control. In a panel study of 43 asthmatic children, 5-13 years old, each child was measured 4 times with a 2-week interval between consecutive clinic visits. At each visit, nasal fluid and urine samples were collected, and fractional exhaled nitric oxide (FeNO) was measured as a biomarker of pulmonary inflammation. In addition to nasal MDA, urinary MDA and 8-hydroxy-2'-deoxyguanosine (8-OHdG) were measured as biomarkers of systemic oxidative stress. We also assessed asthma symptoms using the Childhood Asthma-Control Test (C-ACT). We found that interquartile range (IQR) increases in 24 h average personal PM2.5 exposure (22.2-33.5 µg/m3), estimated 0 to 5 days prior to a clinic visit, were associated with increased nasal MDA concentrations by 38.6-54.9%. Similarly, IQR increases in 24 h average personal O3 exposure (7.7-8.2 ppb) estimated 2 to 4 days prior were associated with increased nasal MDA by 22.1-69.4%. Only increased PM2.5 exposure was associated with increased FeNO. Increased nasal MDA concentration was associated with decreased total and individual C-ACT scores, indicating worsening of asthma symptoms. However, no significant associations were observed between urinary MDA or 8-OHdG and C-ACT scores. The results confirm that oxidative stress plays an important role in linking air pollution exposure and adverse respiratory health effects. These findings support that MDA in the nasal fluid may serve as a useful biomarker for monitoring asthma status, especially in relation to PM2.5 and O3 exposures, two known risk factors of asthma exacerbation.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Asma , Adolescente , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Biomarcadores , Niño , Preescolar , Exposición a Riesgos Ambientales , Humanos , Malondialdehído , Material Particulado/efectos adversos , Material Particulado/análisis
14.
Antimicrob Agents Chemother ; 63(12)2019 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-31570394

RESUMEN

AT-527 is a novel modified guanosine nucleotide prodrug inhibitor of the hepatitis C virus (HCV) NS5B polymerase, with increased in vitro antiviral activity as compared to sofosbuvir and a highly differentiated favorable preclinical profile compared to other anti-HCV nucleoside/nucleotide analogs. This was a multiple part clinical study where multiple ascending doses of AT-527 up to 600 mg (expressed as AT-527 salt form; equivalent to 553 mg free base) once daily for seven days were evaluated in a randomized, double-blind, placebo-controlled study of treatment-naïve, non-cirrhotic, genotype 1b, HCV-infected subjects. The highest dose of AT-527 for the same duration was then evaluated in two open label cohorts of a) non-cirrhotic, genotype 3, HCV-infected subjects and b) HCV-infected subjects of any genotype with compensated (Child-Pugh A) cirrhosis. AT-527 was well tolerated for seven days in all cohorts. At the highest dose tested, mean HCV RNA reductions of up to 2.4 log10 IU/mL occurred within the first 24 hours of dosing. Mean maximum reductions observed with seven days of dosing were 4.4, 4.5 and 4.6 log10 IU/mL in non-cirrhotic subjects with HCV genotype 1b, non-cirrhotic subjects with HCV genotype 3, and subjects with compensated cirrhosis, respectively. The systemic half-life of AT-273, the nucleoside metabolite considered a surrogate of intracellular phosphates including the active triphosphate, exceeded 20 hours, supporting once daily dosing. In summary, AT-527 demonstrated rapid, potent, dose/exposure-related and pan-genotypic antiviral activity with similar responses between subjects with and without cirrhosis. Exposure-antiviral response analysis identified 550 mg (free base equivalent) as the optimal dose of AT-527. Safety and antiviral activity data from this study warrant continued clinical development of AT-527 dosed once daily.

15.
Plant Biotechnol J ; 17(4): 762-775, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30220108

RESUMEN

Upland cotton (Gossypium hirsutum) is the world's largest source of natural fibre and dominates the global textile industry. Hybrid cotton varieties exhibit strong heterosis that confers high fibre yields, yet the genome-wide effects of artificial selection that have influenced Upland cotton during its breeding history are poorly understood. Here, we resequenced Upland cotton genomes and constructed a variation map of an intact breeding pedigree comprising seven elite and 19 backbone parents. Compared to wild accessions, the 26 pedigree accessions underwent strong artificial selection during domestication that has resulted in reduced genetic diversity but stronger linkage disequilibrium and higher extents of selective sweeps. In contrast to the backbone parents, the elite parents have acquired significantly improved agronomic traits, with an especially pronounced increase in the lint percentage. Notably, identify by descent (IBD) tracking revealed that the elite parents inherited abundant beneficial trait segments and loci from the backbone parents and our combined analyses led to the identification of a core genomic segment which was inherited in the elite lines from the parents Zhong 7263 and Ejing 1 and that was strongly associated with lint percentage. Additionally, SNP correlation analysis of this core segment showed that a non-synonymous SNP (A-to-G) site in a gene encoding the cell wall-associated receptor-like kinase 3 (GhWAKL3) protein was highly correlated with increased lint percentage. Our results substantially increase the valuable genomics resources available for future genetic and functional genomics studies of cotton and reveal insights that will facilitate yield increases in the molecular breeding of cotton.


Asunto(s)
Genoma de Planta/genética , Genómica , Gossypium/genética , Productos Agrícolas , Domesticación , Sitios Genéticos , Genotipo , Desequilibrio de Ligamiento , Linaje , Fenotipo , Fitomejoramiento
16.
Theor Appl Genet ; 132(7): 1991-2002, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30982110

RESUMEN

KEY MESSAGE: A genome-wide associated study identified six novel QTLs for lint percentage. Two candidate genes underlying this trait were also detected. Increasing lint percentage (LP) is a core goal of cotton breeding. To better understand the genetic basis of LP, a genome-wide association study (GWAS) was conducted using 276 upland cotton accessions planted in multiple environments and genotyped with a CottonSNP63K array. After filtering, 10,660 high-quality single-nucleotide polymorphisms (SNPs) were retained. Population structure, principal component and neighbor-joining phylogenetic tree analyses divided the accessions into two subpopulations. These results along with linkage disequilibrium decay indicated accessions were not highly structured and exhibited weak relatedness. GWAS uncovered 23 polymorphic SNPs and 15 QTLs significantly associated with LP, with six new QTLs identified. Two candidate genes, Gh_D05G0313 and Gh_D05G1124, both contained one significant SNP, highly expressed during ovule and fiber development stages, implying that the two genes may act as the most promising regulators of LP. Furthermore, the phenotypic value of LP was found to be positively correlated with the number of favorable SNP alleles. These favorable alleles for LP identified in the study may be useful for improving lint yield.


Asunto(s)
Fibra de Algodón , Gossypium/genética , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Estudios de Asociación Genética , Genética de Población , Genoma de Planta , Genotipo , Desequilibrio de Ligamiento , Fenotipo , Fitomejoramiento
17.
J Org Chem ; 84(7): 4381-4391, 2019 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-30865449

RESUMEN

An organocatalyzed dearomative aza-Michael/Michael addition cascade of 2-nitrobenzofurans and 2-nitrobenzothiophenes with 2-aminochalcones has been developed, opening a new channel to access a series of optically active tetrahydrobenzofuro[3,2- b]quinolines and tetrahydrobenzo[4,5]thieno[3,2- b]quinolines bearing three contiguous stereocenters with excellent diastereo- and enantioselectivities (all cases >20:1 dr, up to 99% ee). This study features the first asymmetric dearomative cascade reaction of 2-nitrobenzofurans and 2-nitrobenzothiophenes beginning with aza-Michael addition. The potential applications of the methodology were demonstrated by the preparative-scale experiment and the versatile transformations of the products.

18.
J Nat Prod ; 82(2): 368-374, 2019 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-30693772

RESUMEN

Cultivation of the mangrove rhizosphere soil-derived fungus Penicillium janthinellum HK1-6 with NaBr led to the isolation of two new brominated azaphilones, penicilones G and H (5, 6), two new tricyclic polyketides, penijanthinones A and B (7, 8), and two known azaphilones, penicilones A and B (1, 2). The planar structures and relative configurations of the new compounds were elucidated using comprehensive spectroscopic methods including 1D and 2D NOE spectra. Their absolute configurations were determined by chemical conversions, TDDFT ECD calculations, and comparisons of their ECD spectra. Interestingly, the NaBr-induced brominated azaphilones (5, 6) had the opposite configuration at C-7 compared to the chloro analogues (3, 4) produced by this fungus cultivated with sea salt. Ester hydrolysis of penicilone B (2) afforded the carboxylic acid side chain 2,4-dimethyldec-2-enoic acid (9), with a 4 S configuration assigned by its specific rotation. Penicilone H (6) showed antibacterial activity with MIC values ranging from 3.13 to 12.5 µg/mL.


Asunto(s)
Benzopiranos/metabolismo , Penicillium/metabolismo , Policétidos/metabolismo , Microbiología del Suelo , Benzopiranos/química , Benzopiranos/farmacología , Bromuros/farmacología , Línea Celular Tumoral , Halogenación , Humanos , Espectroscopía de Resonancia Magnética , Policétidos/química , Policétidos/farmacología , Compuestos de Sodio/farmacología
19.
BMC Pediatr ; 19(1): 79, 2019 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-30885166

RESUMEN

BACKGROUND: Maternofetal carnitine transport through the placenta is the main route of fetal carnitine uptake. Decreased free carnitine levels discovered by newborn screening has identified many asymptomatic adult women with systemic primary carnitine deficiency (PCD). Here, we presented amplitude integrated electroencephalogram (aEEG) and magnetic resonance imaging (MRI) findings from a neonate with epilepsy whose mother was carnitine deficient. CASE PRESENTATION: A one-day-old female newborn was admitted after experiencing seizures for half a day; status epilepticus was found on the continuous normal voltage background pattern with immature sleep-wake cycling during aEEG monitoring. On T1-weighted, T2-weighted, FLAIR, and DWI head MRI, there were various degrees of hyperintense signals and diffusion restrictions in the deep white matter of the right hemisphere. Tandem mass spectrometry discovered carnitine deficiency on the second day, which elevated to normal by the 9th day before L-carnitine supplementation was started. The patient was treated with phenobarbital after admission. No further seizures were noted by day 5. It was confirmed that the patient's mother had a low level of serum-free carnitine. Gene analyses revealed that the newborn had heterozygote mutations on c.1400C > G of the SLC22A5 gene, and her mother had homozygous mutations on c.1400C > G. The patient had a good outcome at the 8-month follow up. CONCLUSIONS: Maternal carnitine deficiency that occurs during the perinatal period may manifest as secondary epilepsy with cerebral injury in neonates. The short-term neurodevelopmental outcomes were good. Early diagnosis of asymptomatic PCD in female patients can provide guidance for future pregnancies.


Asunto(s)
Cardiomiopatías/complicaciones , Carnitina/deficiencia , Hiperamonemia/complicaciones , Enfermedades Musculares/complicaciones , Convulsiones/etiología , Encéfalo/diagnóstico por imagen , Cardiomiopatías/diagnóstico , Cardiomiopatías/genética , Carnitina/sangre , Carnitina/genética , Electroencefalografía , Femenino , Enfermedades Fetales/etiología , Humanos , Hiperamonemia/diagnóstico , Hiperamonemia/genética , Recién Nacido , Enfermedades del Recién Nacido/diagnóstico , Imagen por Resonancia Magnética , Madres , Enfermedades Musculares/diagnóstico , Enfermedades Musculares/genética , Mutación
20.
Mar Drugs ; 17(6)2019 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-31159234

RESUMEN

Three novel monomeric naphtho-γ-pyrones, peninaphones A-C (compounds 1-3), along with two known bis-naphtho-γ-pyrones (compounds 4 and 5) were isolated from mangrove rhizosphere soil-derived fungus Penicillium sp. HK1-22. The absolute configurations of compounds 1 and 2 were determined by electronic circular dichroism (ECD) spectra, and the structure of compound 3 was confirmed by single-crystal X-ray diffraction analysis. Compounds 4 and 5 are a pair of hindered rotation isomers. A hypothetical biosynthetic pathway for the isolated monomeric and dimeric naphtho-γ-pyrones is also discussed in this study. Compounds 1-3 showed antibacterial activity against Staphylococcus aureus (ATCC 43300, 33591, 29213, and 25923) with minimum inhibitory concentration (MIC) values in the range of 12.5-50 µg/mL. Compound 3 exhibited significant activity against the rice sheath blight pathogen Rhizoctonia solani.


Asunto(s)
Organismos Acuáticos/química , Basidiomycota/efectos de los fármacos , Penicillium/química , Pironas/química , Pironas/farmacología , Staphylococcus aureus/efectos de los fármacos , Antiinfecciosos/química , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Dicroismo Circular , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Difracción de Rayos X
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