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1.
N Engl J Med ; 386(21): 2011-2023, 2022 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-35544369

RESUMEN

BACKGROUND: Vaccination of children to prevent coronavirus disease 2019 (Covid-19) is an urgent public health need. The safety, immunogenicity, and efficacy of the mRNA-1273 vaccine in children 6 to 11 years of age are unknown. METHODS: Part 1 of this ongoing phase 2-3 trial was open label for dose selection; part 2 was an observer-blinded, placebo-controlled expansion evaluation of the selected dose. In part 2, we randomly assigned children (6 to 11 years of age) in a 3:1 ratio to receive two injections of mRNA-1273 (50 µg each) or placebo, administered 28 days apart. The primary objectives were evaluation of the safety of the vaccine in children and the noninferiority of the immune response in these children to that in young adults (18 to 25 years of age) in a related phase 3 trial. Secondary objectives included determination of the incidences of confirmed Covid-19 and severe acute respiratory syndrome coronavirus 2 infection, regardless of symptoms. Interim analysis results are reported. RESULTS: In part 1 of the trial, 751 children received 50-µg or 100-µg injections of the mRNA-1273 vaccine, and on the basis of safety and immunogenicity results, the 50-µg dose level was selected for part 2. In part 2 of the trial, 4016 children were randomly assigned to receive two injections of mRNA-1273 (50 µg each) or placebo and were followed for a median of 82 days (interquartile range, 14 to 94) after the first injection. This dose level was associated with mainly low-grade, transient adverse events, most commonly injection-site pain, headache, and fatigue. No vaccine-related serious adverse events, multisystem inflammatory syndrome in children, myocarditis, or pericarditis were reported as of the data-cutoff date. One month after the second injection (day 57), the neutralizing antibody titer in children who received mRNA-1273 at a 50-µg level was 1610 (95% confidence interval [CI], 1457 to 1780), as compared with 1300 (95% CI, 1171 to 1443) at the 100-µg level in young adults, with serologic responses in at least 99.0% of the participants in both age groups, findings that met the prespecified noninferiority success criterion. Estimated vaccine efficacy was 88.0% (95% CI, 70.0 to 95.8) against Covid-19 occurring 14 days or more after the first injection, at a time when B.1.617.2 (delta) was the dominant circulating variant. CONCLUSIONS: Two 50-µg doses of the mRNA-1273 vaccine were found to be safe and effective in inducing immune responses and preventing Covid-19 in children 6 to 11 years of age; these responses were noninferior to those in young adults. (Funded by the Biomedical Advanced Research and Development Authority and the National Institute of Allergy and Infectious Diseases; KidCOVE ClinicalTrials.gov number, NCT04796896.).


Asunto(s)
Vacuna nCoV-2019 mRNA-1273 , COVID-19 , Vacuna nCoV-2019 mRNA-1273/efectos adversos , Vacuna nCoV-2019 mRNA-1273/inmunología , Vacuna nCoV-2019 mRNA-1273/uso terapéutico , Adolescente , Adulto , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , COVID-19/sangre , COVID-19/complicaciones , COVID-19/inmunología , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Vacunas contra la COVID-19/uso terapéutico , Niño , Método Doble Ciego , Humanos , SARS-CoV-2 , Síndrome de Respuesta Inflamatoria Sistémica , Eficacia de las Vacunas , Adulto Joven
2.
N Engl J Med ; 387(18): 1673-1687, 2022 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-36260859

RESUMEN

BACKGROUND: The safety, reactogenicity, immunogenicity, and efficacy of the mRNA-1273 coronavirus disease 2019 (Covid-19) vaccine in young children are unknown. METHODS: Part 1 of this ongoing phase 2-3 trial was open label for dose selection; part 2 was an observer-blinded, placebo-controlled evaluation of the selected dose. In part 2, we randomly assigned young children (6 months to 5 years of age) in a 3:1 ratio to receive two 25-µg injections of mRNA-1273 or placebo, administered 28 days apart. The primary objectives were to evaluate the safety and reactogenicity of the vaccine and to determine whether the immune response in these children was noninferior to that in young adults (18 to 25 years of age) in a related phase 3 trial. Secondary objectives were to determine the incidences of Covid-19 and severe acute respiratory syndrome coronavirus 2 infection after administration of mRNA-1273 or placebo. RESULTS: On the basis of safety and immunogenicity results in part 1 of the trial, the 25-µg dose was evaluated in part 2. In part 2, 3040 children 2 to 5 years of age and 1762 children 6 to 23 months of age were randomly assigned to receive two 25-µg injections of mRNA-1273; 1008 children 2 to 5 years of age and 593 children 6 to 23 months of age were randomly assigned to receive placebo. The median duration of follow-up after the second injection was 71 days in the 2-to-5-year-old cohort and 68 days in the 6-to-23-month-old cohort. Adverse events were mainly low-grade and transient, and no new safety concerns were identified. At day 57, neutralizing antibody geometric mean concentrations were 1410 (95% confidence interval [CI], 1272 to 1563) among 2-to-5-year-olds and 1781 (95% CI, 1616 to 1962) among 6-to-23-month-olds, as compared with 1391 (95% CI, 1263 to 1531) among young adults, who had received 100-µg injections of mRNA-1273, findings that met the noninferiority criteria for immune responses for both age cohorts. The estimated vaccine efficacy against Covid-19 was 36.8% (95% CI, 12.5 to 54.0) among 2-to-5-year-olds and 50.6% (95% CI, 21.4 to 68.6) among 6-to-23-month-olds, at a time when B.1.1.529 (omicron) was the predominant circulating variant. CONCLUSIONS: Two 25-µg doses of the mRNA-1273 vaccine were found to be safe in children 6 months to 5 years of age and elicited immune responses that were noninferior to those in young adults. (Funded by the Biomedical Advanced Research and Development Authority and National Institute of Allergy and Infectious Diseases; KidCOVE ClinicalTrials.gov number, NCT04796896.).


Asunto(s)
Vacuna nCoV-2019 mRNA-1273 , COVID-19 , Inmunogenicidad Vacunal , Niño , Preescolar , Humanos , Lactante , Adulto Joven , Vacuna nCoV-2019 mRNA-1273/inmunología , Vacuna nCoV-2019 mRNA-1273/uso terapéutico , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/epidemiología , COVID-19/inmunología , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Método Doble Ciego , Inmunogenicidad Vacunal/inmunología , Eficacia de las Vacunas , Resultado del Tratamiento , Adolescente , Adulto
3.
Exp Cell Res ; 434(1): 113877, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-38072302

RESUMEN

Exploration of the molecular mechanisms of mesenchymal stem cell (MSC) growth has significant clinical benefits. Long non-coding RNAs (lncRNAs) have been reported to play vital roles in the regulation of the osteogenic differentiation of MSCs. However, the mechanism by which lncRNA affects the proliferation and apoptosis of MSCs is unclear. In this study, sequencing analysis revealed that LINC00707 was significantly decreased in non-adherent human MSCs (non-AC-hMSCs) compared to adherent human MSCs. Moreover, LINC00707 overexpression promoted non-AChMSC proliferation, cell cycle progression from the G0/G1 phase to the S phase and inhibited apoptosis, whereas LINC00707 silencing had the opposite effect. Furthermore, LINC00707 interacted directly with the quaking (QKI) protein and enhanced the E3 ubiquitin-protein ligase ring finger protein 6 (RNF6)-mediated ubiquitination of the QKI protein. Additionally, the overexpression of QKI rescued the promotive effects on proliferation and inhibitory effects on apoptosis in non-AC-hMSCs induced by the ectopic expression of LINC00707. Thus, LINC00707 contributes to the proliferation and apoptosis in non-AChMSCs by regulating the ubiquitination and degradation of the QKI protein.


Asunto(s)
Células Madre Mesenquimatosas , ARN Largo no Codificante , Humanos , Osteogénesis/genética , Proliferación Celular/genética , Apoptosis/genética , Células Madre Mesenquimatosas/metabolismo , Ubiquitinación , ARN Largo no Codificante/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ARN/metabolismo
4.
J Infect Dis ; 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38349280

RESUMEN

BACKGROUND: Monovalent Omicron XBB.1.5-containing vaccines were approved for Coronavirus disease 2019 (COVID-19) 2023-2024 immunizations. METHODS: This ongoing, open-label, phase 2/3 study evaluated mRNA-1273.815-monovalent (50-µg Omicron XBB.1.5-spike mRNA) and mRNA-1273.231-bivalent (25-µg each Omicron XBB.1.5- and BA.4/BA.5-spike mRNAs))vaccines, administered as 5th doses to adults who previously received a primary series, a 3rd dose of an original mRNA COVID-19 vaccine, and a 4th dose of an Omicron BA.4/BA.5 bivalent vaccine. Interim safety and immunogenicity results 29 days post-vaccination are reported. RESULTS: Participants (randomized 1:1) received 50-µg mRNA-1273.815(n=50) or mRNA-1273.231(n=51); median (interquartile range) months from the prior BA.4/BA.5-bivalent dose were 8.2 (8.1-8.3) and 8.3 (8.1-8.4), respectively. Neutralizing antibody (nAb) increased from pre-booster levels against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants tested. Day 29 nAb fold-increases from pre-booster levels were numerically higher against XBB.1.5, XBB.1.16, EG.5.1, BA.2.86, and JN.1 than BA.4/BA.5, BQ.1.1 and D614G. The monovalent vaccine also cross-neutralized FL.1.5.1, EG.5.1, BA.2.86, HK.3.1, HV.1 and JN.1 variants in a participant (n=20) subset, 15 days post-vaccination. Reactogenicity was similar to previously reported mRNA-1273 original and bivalent vaccines. CONCLUSIONS: XBB.1.5-containing mRNA-1273 vaccines elicit robust, diverse nAb responses against more recent SARS-CoV-2 variants including JN.1, supporting the XBB.1.5-spike sequence selection for the 2023-2024 COVID-19 vaccine update.

5.
N Engl J Med ; 385(24): 2241-2251, 2021 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-34379915

RESUMEN

BACKGROUND: The incidence of coronavirus disease 2019 (Covid-19) among adolescents between 12 and 17 years of age was approximately 900 per 100,000 population from April 1 through June 11, 2021. The safety, immunogenicity, and efficacy of the mRNA-1273 vaccine in adolescents are unknown. METHODS: In this ongoing phase 2-3, placebo-controlled trial, we randomly assigned healthy adolescents (12 to 17 years of age) in a 2:1 ratio to receive two injections of the mRNA-1273 vaccine (100 µg in each) or placebo, administered 28 days apart. The primary objectives were evaluation of the safety of mRNA-1273 in adolescents and the noninferiority of the immune response in adolescents as compared with that in young adults (18 to 25 years of age) in a phase 3 trial. Secondary objectives included the efficacy of mRNA-1273 in preventing Covid-19 or asymptomatic severe acute respiratory syndrome coronavirus 2 infection. RESULTS: A total of 3732 participants were randomly assigned to receive mRNA-1273 (2489 participants) or placebo (1243 participants). In the mRNA-1273 group, the most common solicited adverse reactions after the first or second injections were injection-site pain (in 93.1% and 92.4%, respectively), headache (in 44.6% and 70.2%, respectively), and fatigue (in 47.9% and 67.8%, respectively); in the placebo group, the most common solicited adverse reactions after the first or second injections were injection-site pain (in 34.8% or 30.3%, respectively), headache (in 38.5% and 30.2%, respectively), and fatigue (in 36.6% and 28.9%, respectively). No serious adverse events related to mRNA-1273 or placebo were noted. The geometric mean titer ratio of pseudovirus neutralizing antibody titers in adolescents relative to young adults was 1.08 (95% confidence interval [CI], 0.94 to 1.24), and the absolute difference in serologic response was 0.2 percentage points (95% CI, -1.8 to 2.4), which met the noninferiority criterion. No cases of Covid-19 with an onset of 14 days after the second injection were reported in the mRNA-1273 group, and four cases occurred in the placebo group. CONCLUSIONS: The mRNA-1273 vaccine had an acceptable safety profile in adolescents. The immune response was similar to that in young adults, and the vaccine was efficacious in preventing Covid-19. (Funded by Moderna and the Biomedical Advanced Research and Development Authority; Teen COVE ClinicalTrials.gov number, NCT04649151.).


Asunto(s)
Vacuna nCoV-2019 mRNA-1273 , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , COVID-19/prevención & control , Inmunogenicidad Vacunal , Vacuna nCoV-2019 mRNA-1273/administración & dosificación , Vacuna nCoV-2019 mRNA-1273/efectos adversos , Vacuna nCoV-2019 mRNA-1273/inmunología , Adolescente , Niño , Femenino , Humanos , Masculino , Método Simple Ciego , Eficacia de las Vacunas
6.
N Engl J Med ; 384(5): 403-416, 2021 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-33378609

RESUMEN

BACKGROUND: Vaccines are needed to prevent coronavirus disease 2019 (Covid-19) and to protect persons who are at high risk for complications. The mRNA-1273 vaccine is a lipid nanoparticle-encapsulated mRNA-based vaccine that encodes the prefusion stabilized full-length spike protein of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes Covid-19. METHODS: This phase 3 randomized, observer-blinded, placebo-controlled trial was conducted at 99 centers across the United States. Persons at high risk for SARS-CoV-2 infection or its complications were randomly assigned in a 1:1 ratio to receive two intramuscular injections of mRNA-1273 (100 µg) or placebo 28 days apart. The primary end point was prevention of Covid-19 illness with onset at least 14 days after the second injection in participants who had not previously been infected with SARS-CoV-2. RESULTS: The trial enrolled 30,420 volunteers who were randomly assigned in a 1:1 ratio to receive either vaccine or placebo (15,210 participants in each group). More than 96% of participants received both injections, and 2.2% had evidence (serologic, virologic, or both) of SARS-CoV-2 infection at baseline. Symptomatic Covid-19 illness was confirmed in 185 participants in the placebo group (56.5 per 1000 person-years; 95% confidence interval [CI], 48.7 to 65.3) and in 11 participants in the mRNA-1273 group (3.3 per 1000 person-years; 95% CI, 1.7 to 6.0); vaccine efficacy was 94.1% (95% CI, 89.3 to 96.8%; P<0.001). Efficacy was similar across key secondary analyses, including assessment 14 days after the first dose, analyses that included participants who had evidence of SARS-CoV-2 infection at baseline, and analyses in participants 65 years of age or older. Severe Covid-19 occurred in 30 participants, with one fatality; all 30 were in the placebo group. Moderate, transient reactogenicity after vaccination occurred more frequently in the mRNA-1273 group. Serious adverse events were rare, and the incidence was similar in the two groups. CONCLUSIONS: The mRNA-1273 vaccine showed 94.1% efficacy at preventing Covid-19 illness, including severe disease. Aside from transient local and systemic reactions, no safety concerns were identified. (Funded by the Biomedical Advanced Research and Development Authority and the National Institute of Allergy and Infectious Diseases; COVE ClinicalTrials.gov number, NCT04470427.).


Asunto(s)
Vacunas contra la COVID-19 , COVID-19/prevención & control , SARS-CoV-2 , Vacuna nCoV-2019 mRNA-1273 , Adolescente , Adulto , Anciano , COVID-19/diagnóstico , COVID-19/inmunología , Vacunas contra la COVID-19/efectos adversos , Vacunas contra la COVID-19/inmunología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Gravedad del Paciente , Método Simple Ciego , Glicoproteína de la Espiga del Coronavirus , Resultado del Tratamiento , Adulto Joven
7.
N Engl J Med ; 385(19): 1774-1785, 2021 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-34551225

RESUMEN

BACKGROUND: At interim analysis in a phase 3, observer-blinded, placebo-controlled clinical trial, the mRNA-1273 vaccine showed 94.1% efficacy in preventing coronavirus disease 2019 (Covid-19). After emergency use of the vaccine was authorized, the protocol was amended to include an open-label phase. Final analyses of efficacy and safety data from the blinded phase of the trial are reported. METHODS: We enrolled volunteers who were at high risk for Covid-19 or its complications; participants were randomly assigned in a 1:1 ratio to receive two intramuscular injections of mRNA-1273 (100 µg) or placebo, 28 days apart, at 99 centers across the United States. The primary end point was prevention of Covid-19 illness with onset at least 14 days after the second injection in participants who had not previously been infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The data cutoff date was March 26, 2021. RESULTS: The trial enrolled 30,415 participants; 15,209 were assigned to receive the mRNA-1273 vaccine, and 15,206 to receive placebo. More than 96% of participants received both injections, 2.3% had evidence of SARS-CoV-2 infection at baseline, and the median follow-up was 5.3 months in the blinded phase. Vaccine efficacy in preventing Covid-19 illness was 93.2% (95% confidence interval [CI], 91.0 to 94.8), with 55 confirmed cases in the mRNA-1273 group (9.6 per 1000 person-years; 95% CI, 7.2 to 12.5) and 744 in the placebo group (136.6 per 1000 person-years; 95% CI, 127.0 to 146.8). The efficacy in preventing severe disease was 98.2% (95% CI, 92.8 to 99.6), with 2 cases in the mRNA-1273 group and 106 in the placebo group, and the efficacy in preventing asymptomatic infection starting 14 days after the second injection was 63.0% (95% CI, 56.6 to 68.5), with 214 cases in the mRNA-1273 group and 498 in the placebo group. Vaccine efficacy was consistent across ethnic and racial groups, age groups, and participants with coexisting conditions. No safety concerns were identified. CONCLUSIONS: The mRNA-1273 vaccine continued to be efficacious in preventing Covid-19 illness and severe disease at more than 5 months, with an acceptable safety profile, and protection against asymptomatic infection was observed. (Funded by the Biomedical Advanced Research and Development Authority and the National Institute of Allergy and Infectious Diseases; COVE ClinicalTrials.gov number, NCT04470427.).


Asunto(s)
Vacunas contra la COVID-19/inmunología , COVID-19/prevención & control , Inmunogenicidad Vacunal , Vacuna nCoV-2019 mRNA-1273 , Adolescente , Adulto , Anciano , COVID-19/epidemiología , Vacunas contra la COVID-19/efectos adversos , Estudios de Seguimiento , Humanos , Inmunización Secundaria , Incidencia , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Gravedad del Paciente , Método Simple Ciego , Resultado del Tratamiento , Adulto Joven
8.
Biochem Genet ; 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38429602

RESUMEN

BACKGROUND: Solamargine (SM) has been shown to play anti-tumor role in hepatocellular carcinoma (HCC). However, the underlying molecular mechanisms of SM in HCC progression deserve further exploration. METHODS: HCC cell proliferation and apoptosis were assessed by cell counting kit 8 assay, colony formation assay and flow cytometry. Ferroptosis was evaluated by detecting the levels of Fe2+, iron, MDA, ROS and GSH in HCC cells. In addition, mitochondrial carrier 1 (MTCH1) mRNA level was detected by quantitative real-time PCR. Western blot was used to test MTCH1 and signal transduction and activation of transcription 1 (STAT1) protein levels. Dual-luciferase reporter assay was employed to analyze the interaction between STAT1 and MTCH1. A mouse xenograft model was also constructed to explore the role of SM in vivo. RESULTS: SM could potentially suppress HCC cell growth by inducing ferroptosis. MTCH1 was highly expressed in HCC tissues and cells, and its silencing inhibited HCC cell proliferation, promoted apoptosis and ferroptosis. MTCH1 expression was reduced by SM, and its overexpression reversed SM-induced HCC cell apoptosis and ferroptosis. Furthermore, STAT1 facilitated MTCH1 transcription and promoted its expression. Besides, STAT1 expression could be reduced by SM, and its overexpression abolished the decreasing effect of SM on MTCH1 expression. In vivo, SM suppressed HCC tumor growth by reducing MTCH1 expression. CONCLUSION: SM promoted HCC cell apoptosis and ferroptosis via the STAT1/MTCH1 axis.

9.
Angew Chem Int Ed Engl ; 63(13): e202318476, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38288790

RESUMEN

Herein, we have synthesized multifunctionalized 2-oxa-3-azabicyclo[3.1.1]heptanes, which are considered potential bioisosteres for meta-substituted arenes, through Eu(OTf)3 -catalyzed formal dipolar [4π+2σ] cycloaddition of bicyclo[1.1.0]butanes with nitrones. This methodology represents the initial instance of fabricating bicyclo[3.1.1]heptanes adorned with multiple heteroatoms. The protocol exhibits both mild reaction conditions and a good tolerance for various functional groups. Computational density functional theory calculations support that the reaction mechanism likely involves a nucleophilic addition of nitrones to bicyclo[1.1.0]butanes, succeeded by an intramolecular cyclization. The synthetic utility of this novel protocol has been demonstrated in the concise synthesis of the analogue of Rupatadine.

10.
Clin Infect Dis ; 76(2): 271-280, 2023 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-36130187

RESUMEN

BACKGROUND: The reactogenicity and immunogenicity of coronavirus disease 2019 (COVID-19) vaccines are well studied. Little is known regarding the relationship between immunogenicity and reactogenicity of COVID-19 vaccines. METHODS: This study assessed the association between immunogenicity and reactogenicity after 2 mRNA-1273 (100 µg) injections in 1671 total adolescent and adult participants (≥12 years) from the primary immunogenicity sets of the blinded periods of the Coronavirus Efficacy (COVE) and TeenCOVE trials. Associations between immunogenicity through day 57 and solicited adverse reactions (ARs) after the first and second injections of mRNA-1273 were evaluated among participants with and without solicited ARs using linear mixed-effects models. RESULTS: mRNA-1273 reactogenicity in this combined analysis set was similar to that reported for these trials. The vaccine elicited high neutralizing antibody (nAb) geometric mean titers (GMTs) in evaluable participants. GMTs at day 57 were significantly higher in participants who experienced solicited systemic ARs after the second injection (1227.2 [1164.4-1293.5]) than those who did not (980.1 [886.8-1083.2], P = .001) and were associated with fever, chills, headache, fatigue, myalgia, and arthralgia. Significant associations with local ARs were not found. CONCLUSIONS: These data show an association of systemic ARs with increased nAb titers following a second mRNA-1273 injection. While these data indicate systemic ARs are associated with increased antibody titers, high nAb titers were observed in participants after both injections, consistent with the immunogenicity and efficacy in these trials. These results add to the body of evidence regarding the relationship of immunogenicity and reactogenicity and can contribute toward the design of future mRNA vaccines.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Adulto , Adolescente , Humanos , Vacunas contra la COVID-19/efectos adversos , Vacuna nCoV-2019 mRNA-1273 , SARS-CoV-2 , COVID-19/prevención & control , Anticuerpos Neutralizantes , Inmunogenicidad Vacunal , Anticuerpos Antivirales
11.
Chemistry ; 29(33): e202300536, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-36959094

RESUMEN

Sulfur(VI)-fluoride exchange linkage as a next generation of click chemistry was introduced by Sharpless and coworkers in 2014. Distinguished from CuAAC, the SuFEx reaction proceeds under metal-free conditions, and the reactive linkers are variable, enabling access to a diverse class of linkage compounds. Therein, a series of SuFEx linkers emerged has been widely prevalent in diverse fields. The SVI -F bond in comparison to SVI -Cl bond features excellent stability and chemoselectivity. The linkage chemistry primarily involves the formation of S-O and S-N bonds via commercially available phenols and amines, yet less study on C-SuFEx linkage. This review will focus on three types of linkage for SuFEx linkers comprising S-O, S-N, and S-C bonds, and we hope to provide a practical guidance for SuFEx linkage chemistry.


Asunto(s)
Fluoruros , Fluoruros/química , Química Clic , Azufre/química , Polímeros/química , Nitrógeno/química
12.
Environ Geochem Health ; 45(12): 9029-9040, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36183309

RESUMEN

Yunnan Province is the main planting area of the precious Chinese herbal medicines (CHM) Panax notoginseng; however, it locates the geological area with high soil heavy metals in China. The frequent land replacement due to continuous cropping obstacles and excessive application of chemicals makes P. notoginseng prone to be contaminated by heavy metals under the farmland P. notoginseng (FPn) planting. To overcome farmland shortage, understory P. notoginseng (UPn) was developed as a new ecological planting model featured by no chemicals input. However, this newly developed planting system requires urgently the soil-plant heavy metal characteristics and risk assessment. This study aimed to evaluate the pollution status of eight heavy metals in the tillage layer (0-20 cm), subsoil layer (20-40 cm) and the plants of UPn in Lancang County, Yunnan Province. Pollution index (Pi) showed that the contamination degree of heavy metals in the tillage layer and subsoil layer was Cd > Pb > Ni > Cu > Zn > Cr > Hg > As and Pb > Cd > Cu > Ni > Cr > Hg > Zn > As, respectively. Potential ecological risk index (PERI) for the tillage layer and subsoil layer was slight and middle, respectively. The exceeding standard rate of Cd, As, Pb, Hg, Cu in the UPn roots was 5.33%, 5.33%, 13.33%, 26.67% and 1.33%, respectively, while only Cd and Hg in the UPn leaves exceeded the standard 10% and 14%, respectively. The enrichment abilities of Cd and Hg in the roots and leaves of UPn were the strongest, while that of Pb was the weakest. The Hazard index (HI) and target hazard quotient (THQ) of eight heavy metals in the roots and leaves of UPn were less than 1.Therefore, our results prove that Upn has no human health risk and provide a scientific basis for the safety evaluation and extension of UPn.


Asunto(s)
Mercurio , Metales Pesados , Panax notoginseng , Contaminantes del Suelo , Cadmio , Plomo , Monitoreo del Ambiente/métodos , China , Contaminantes del Suelo/análisis , Metales Pesados/análisis , Suelo , Medición de Riesgo
13.
J Infect Dis ; 226(10): 1731-1742, 2022 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-35535503

RESUMEN

BACKGROUND: Messenger RNA (mRNA)-1273 vaccine demonstrated 93.2% efficacy against coronavirus disease 2019 (COVID-19) in the Coronavirus Efficacy (COVE) trial. The humoral immunogenicity results are now reported. METHODS: Participants received 2 mRNA-1273 (100 µg) or placebo injections, 28 days apart. Immune responses were evaluated in a prespecified, randomly selected per-protocol immunogenicity population (n = 272 placebo; n = 1185 mRNA-1273). Serum binding antibodies (bAbs) and neutralizing antibodies (nAbs) to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-spike protein were assessed at days 1, 29, and 57 by baseline SARS-CoV-2-negative (n = 1197) and SARS-CoV-2-positive (n = 260) status, age, and sex. RESULTS: SARS-CoV-2-negative vaccinees had bAb geometric mean AU/mL levels of 35 753 at day 29 that increased to 316 448 at day 57 and nAb inhibitory dilution 50% titers of 55 at day 29 that rose to 1081 at day 57. In SARS-CoV-2-positive vacinees, the first mRNA-1273 injection elicited bAb and nAb levels that were 11-fold (410 049) and 27-fold (1479) higher than in SARS-CoV-2-negative vaccinees, respectively, and were comparable to levels after 2 injections in uninfected participants. Findings were generally consistent by age and sex. CONCLUSIONS: mRNA-1273 elicited robust serologic immune responses across age, sex, and SARS-CoV-2 status, consistent with its high COVID-19 efficacy. Higher immune responses in those previously infected support a booster-type effect. Clinical Trials Registration. NCT04470427.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Vacuna nCoV-2019 mRNA-1273 , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/prevención & control , Vacunas contra la COVID-19 , Inmunogenicidad Vacunal , ARN Mensajero , Glicoproteína de la Espiga del Coronavirus
14.
Angew Chem Int Ed Engl ; 61(26): e202203661, 2022 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-35446472

RESUMEN

The enantioselective cascade reaction between racemic 2-(1-hydroxyallyl)phenols and alkynols/alkynamides was realized by using a gold and iridium sequential catalytic system. In this procedure, the in situ generated exocyclic vinyl ethers or enamides undergo the asymmetric allylation/spiroketalization with π-ally-Ir amphiphilic species, which provides an efficient and straightforward access to spiroketals and spiroaminals with excellent enantioselectivities. Moreover, racemic 2-(1-hydroxyallyl)anilines were also suitable in this reaction along with a kinetic resolution process, affording enantioenriched spiroaminals and 2-(1-hydroxyallyl)anilines in good yields. The synthetic utility of this method has been demonstrated by efficient enantioselective synthesis of the analogue of Paecilospirone.


Asunto(s)
Oro , Iridio , Compuestos de Anilina , Catálisis , Furanos , Compuestos de Espiro , Estereoisomerismo
15.
Angew Chem Int Ed Engl ; 61(19): e202117079, 2022 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-35212099

RESUMEN

An unprecedented asymmetric γ-allylic alkylation of free dienolates via Sc/Ir dual catalysis is reported, which affords a range of synthetically versatile γ-allylic crotonaldehydes in high efficiency with excellent chemo-, regio-, and enantioselectivities. The dienolates bearing no essential auxiliary groups were generated in situ by scandium triflate-mediated Meinwald rearrangement of vinyloxiranes atom-economically. With the assistance of computational density functional theory calculations, a Sc/Ir bimetallic catalytic cycle was proposed to illustrate the reaction mechanism.


Asunto(s)
Iridio , Escandio , Alquilación , Catálisis , Estereoisomerismo
16.
Angew Chem Int Ed Engl ; 61(44): e202207100, 2022 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-36104295

RESUMEN

Sulfur(VI) fluoride cleavage and exchanging linkage, a new generation of linkage chemistry, exhibits enormous potential for combining a range of functional molecules in an increasing number of fields. Herein, we established a metal-free linkage of unactivated alkenes and sulfonimidoyl fluorides via hydrosulfonimidoylation to construct sulfoximines within minutes. An intermolecular hydride transfer process is the key step, and it occurs via overlap of the LUMO in the sulfonimidoyl cation and HOMO in the unactivated alkene, which was confirmed via control experiments with deuterated compounds. DFT calculations further demonstrated the concerted process involving formation of the S-C(sp3 ) bond and hydride transfer. Remarkably, abundant natural products and pharmaceuticals with multiple heteroatoms and sensitive functional groups have been subjected to the current linkage reaction to achieve various sulfoximine linkages, furnishing the basis for drug discovery and drug conjugation.


Asunto(s)
Alquenos , Productos Biológicos , Alquenos/química , Fluoruros , Catálisis , Azufre , Cationes , Preparaciones Farmacéuticas
17.
Angew Chem Int Ed Engl ; 61(42): e202210207, 2022 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-35924328

RESUMEN

We reported herein an iridium/silver/acid ternary catalytic system to access bisbenzannulated [6,6]-spiroketals in high efficiency with generally high diastereo- and enantioselectivities (up to >20 : 1 dr, >99 % ee). In this procedure, readily available o-alkynylacetophenones undergo cycloisomerization to generate isochromenes in situ that participate in stereoselective allylation/spiroketalization sequence with 2-(1-hydroxyallyl)phenols. Meanwhile, 2-(1-hydroxyallyl)anilines were also compatible in this cascade reaction, furnishing structurally novel bisbenzannulated [6,6]-spiroaminals with good diastereoselectivities (8 : 1-12 : 1 dr) and excellent enantioselectivities (98 %->99 % ee). Moreover, experimental studies and theoretical calculations were performed to illustrate the reaction mechanism and stereochemistry.


Asunto(s)
Iridio , Plata , Compuestos de Anilina , Catálisis , Furanos , Fenoles , Compuestos de Espiro , Estereoisomerismo
18.
Proc Natl Acad Sci U S A ; 115(20): 5093-5098, 2018 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-29712826

RESUMEN

Amino acids are the building blocks for protein biosynthesis and find use in myriad industrial applications including in food for humans, in animal feed, and as precursors for bio-based plastics, among others. However, the development of efficient chemical methods to convert abundant and renewable feedstocks into amino acids has been largely unsuccessful to date. To that end, here we report a heterogeneous catalyst that directly transforms lignocellulosic biomass-derived α-hydroxyl acids into α-amino acids, including alanine, leucine, valine, aspartic acid, and phenylalanine in high yields. The reaction follows a dehydrogenation-reductive amination pathway, with dehydrogenation as the rate-determining step. Ruthenium nanoparticles supported on carbon nanotubes (Ru/CNT) exhibit exceptional efficiency compared with catalysts based on other metals, due to the unique, reversible enhancement effect of NH3 on Ru in dehydrogenation. Based on the catalytic system, a two-step chemical process was designed to convert glucose into alanine in 43% yield, comparable with the well-established microbial cultivation process, and therefore, the present strategy enables a route for the production of amino acids from renewable feedstocks. Moreover, a conceptual process design employing membrane distillation to facilitate product purification is proposed and validated. Overall, this study offers a rapid and potentially more efficient chemical method to produce amino acids from woody biomass components.


Asunto(s)
Aminoácidos/metabolismo , Biomasa , Nanopartículas/química , Nanotubos de Carbono/química , Aminoácidos/química , Catálisis , Hidrogenación , Níquel/química , Rutenio/química
19.
Angew Chem Int Ed Engl ; 60(9): 4712-4719, 2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33230943

RESUMEN

Green synthesis of adipic acid from renewable biomass is a very attractive goal of sustainable chemistry. Herein, we report efficient catalysts for a two-step transformation of cellulose-derived glucose into adipic acid via glucaric acid. Carbon nanotube-supported platinum nanoparticles are found to work efficiently for the oxidation of glucose to glucaric acid. An activated carbon-supported bifunctional catalyst composed of rhenium oxide and palladium is discovered to be powerful for the removal of four hydroxyl groups in glucaric acid, affording adipic acid with a 99 % yield. Rhenium oxide functions for the deoxygenation but is less efficient for four hydroxyl group removal. The co-presence of palladium not only catalyzes the hydrogenation of olefin intermediates but also synergistically facilitates the deoxygenation. This work presents a green route for adipic acid synthesis and offers a bifunctional-catalysis strategy for efficient deoxygenation.


Asunto(s)
Adipatos/síntesis química , Biomasa , Tecnología Química Verde , Adipatos/química , Alquenos/química , Catálisis , Teoría Funcional de la Densidad , Hidrogenación , Nanopartículas del Metal/química , Conformación Molecular , Nanotubos de Carbono/química , Paladio/química , Platino (Metal)/química , Termodinámica
20.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(10): 1069-1074, 2021 Oct 15.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-34719425

RESUMEN

Systemic lupus erythematosus (SLE) is an autoimmune disease involving multiple organs, and lupus nephritis (LN) is the most common renal complication of SLE. Belimumab is a fully humanized monoclonal antibody that can reduce the number of B cells, thereby reducing the formation of autoantibodies. Belimumab can improve SLE response index and SLE disease activity score and delay the progression of LN in both adults and children and thus plays an important role in the treatment of SLE and LN. This article reviews related research reports of belimumab used in the treatment of children and adults with SLE in China and overseas and analyzes the efficacy and safety of belimumab in pediatric patients, in order to provide a reference for the clinical application of belimumab in children with SLE.


Asunto(s)
Lupus Eritematoso Sistémico , Nefritis Lúpica , Anticuerpos Monoclonales Humanizados , Niño , Humanos , Inmunosupresores , Riñón , Lupus Eritematoso Sistémico/tratamiento farmacológico , Resultado del Tratamiento
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