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1.
Lancet Infect Dis ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38614117

RESUMO

BACKGROUND: The Oka varicella vaccine strain remains neurovirulent and can establish lifelong latent infection, raising safety concerns about vaccine-related herpes zoster. In this study, we aimed to evaluate the immunogenicity and safety of a skin-attenuated and neuro-attenuated varicella vaccine candidate (v7D vaccine). METHODS: We did this randomised, double-blind, controlled, phase 2a clinical trial in Jiangsu, China. Healthy children aged 3-12 years with no history of varicella infection or vaccination were enrolled and randomly assigned (1:1:1:1) to receive a single subcutaneous injection of the v7D vaccine at 3·3 log10 plaque forming units (PFU; low-dose v7D group), 3·9 log10 PFU (medium-dose v7D group), and 4·2 log10 PFU (high-dose v7D group), or the positive control varicella vaccine (vOka vaccine group). All the participants, laboratory personnel, and investigators other than the vaccine preparation and management staff were masked to the vaccine allocation. The primary outcome was assessment of the geometric mean titres (GMTs) and seroconversion rates of anti-varicella zoster virus immunoglobulin G (IgG) induced by different dose groups of v7D vaccine at 0, 42, 60, and 90 days after vaccination in the per-protocol set for humoral immune response analysis. Safety was a secondary outcome, focusing on adverse events within 42 days post-vaccination, and serious adverse events within 6 months after vaccination. This study was registered on Chinese Clinical Trial Registry, ChiCTR2000034434. FINDINGS: On Aug 18-21, 2020, 842 eligible volunteers were enrolled and randomly assigned treatment. After three participants withdrew, 839 received a low dose (n=211), middle dose (n=210), or high dose (n=210) of v7D vaccine, or the vOka vaccine (n=208). In the per-protocol set for humoral immune response analysis, the anti-varicella zoster virus IgG antibody response was highest at day 90. At day 90, the seroconversion rates of the low-dose, medium-dose, and high-dose groups of v7D vaccine and the positive control vOka vaccine group were 100·0% (95% CI 95·8-100·0; 87 of 87 participants), 98·9% (93·8-100·0; 87 of 88 participants), 97·8% (92·4-99·7; 91 of 93 participants), and 96·4% (89·8-99·2; 80 of 83 participants), respectively; the GMTs corresponded to values of 30·8 (95% CI 26·2-36·0), 31·3 (26·7-36·6), 28·2 (23·9-33·2), and 38·5 (31·7-46·7). The v7D vaccine, at low dose and medium dose, elicited a humoral immune response similar to that of the vOka vaccine. However, the high-dose v7D vaccine induced a marginally lower GMT compared with the vOka vaccine at day 90 (p=0·027). In the per-protocol set, the three dose groups of the v7D vaccine induced a similar humoral immune response at each timepoint, with no statistically significant differences. The incidence of adverse reactions in the low-dose, medium-dose, and high-dose groups of v7D vaccine was significantly lower than that in the vOka vaccine group (17% [35 of 211 participants], 20% [41 of 210 participants], and 13% [27 of 210 participants] vs 24% [50 of 208 participants], respectively; p=0·025), especially local adverse reactions (10% [22 of 211 participants], 14% [30 of 210 participants] and 9% [18 of 210 participants] vs 18% [38 of 208 participants], respectively; p=0·016). None of the serious adverse events were vaccine related. INTERPRETATION: The three dose groups of the candidate v7D vaccine exhibit similar humoral immunogenicity to the vOka vaccine and are well tolerated. These findings encourage further investigations on two-dose vaccination schedules, efficacy, and the potential safety benefit of v7D vaccine in the future. FUNDING: The National Natural Science Foundation of China, CAMS Innovation Fund for Medical Sciences, the Fundamental Research Funds for the Central Universities, and Beijing Wantai. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

2.
Front Immunol ; 14: 1241153, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37799724

RESUMO

Background: Updated vaccine strategies are needed to protect against new SARS-CoV-2 variants with increased immune escape. Here, information on the safety and immunogenicity of an inactivated Omicron-adapted vaccine is presented, as compared with CoronaVac. Methods: A randomized, double-blind, active-controlled, phase III clinical trial was conducted to compare a modified Omicron-adapted vaccine (Omicron vaccine) with the authorized prototype vaccine (CoronaVac®) as a booster dose. Healthy adults aged ≥18 years, who have previously received 2 or 3 doses of CoronaVac (2C or 3C cohort) at least 6 months before, were enrolled to get a booster dose of Omicron vaccine or CoronaVac in a ratio of 2:1 (2C/3C+1O/1C). Back-up serums after two initial doses of CoronaVac (2C+0) for adults aged 26-45 years were collected from a previous study. Immunogenicity and safety data at 28 days after vaccination were collected and analyzed. One of the primary objectives was to evaluate the superiority of immunogenicity of Omicron vaccine booster against Omicron BA.1, compared with CoronaVac booster against BA.1. Another objective was to evaluate the non-inferiority of immunogenicity of Omicron vaccine booster against BA.1, compared with two initial doses of CoronaVac against ancestral strain. Results: Between June 1st and July 21st, 2022, a total of 1,500 healthy adults were enrolled. Results show that all pre-specified superiority criteria for BA.1 neutralizing antibody were met. Specifically, within the 3C cohort (3C+1O vs. 3C+1C), the geometric mean titers' (GMT) ratio and 95% confidence interval (CI) was 1.64 (1.42, 1.89), with the lower 95%CI ≥1; a GMT ratio of 1.84 (1.57, 2.16) was observed for 2C+1O versus 3C+1C. For seroconversion rate, the lower 95%CIs of differences between immuno-comparative groups (2/3C+1O vs. 3C+1C) were all above the superiority criterion 0%. However, the non-inferiority criterion of the lower 95%CI of GMT ratio ≥2/3 was unfulfilled for 2C/3C+1O against BA.1 versus 2C+0 against ancestral strain. Safety profiles were similar between groups, with no safety concerns identified. Conclusion: The Omicron-adapted vaccine was well-tolerated and could elicit superior immune responses as compared with CoronaVac against Omicron, while it appeared inferior to CoronaVac against ancestral strain. Clinical trial registration: https://classic.clinicaltrials.gov/ct2/show/NCT05381350?term=NCT05381350&draw=2&rank=1, identifier NCT05381350.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Adolescente , Adulto , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , SARS-CoV-2 , Vacinas de Produtos Inativados/efeitos adversos , Método Duplo-Cego
3.
Angew Chem Int Ed Engl ; 62(23): e202303668, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37032316

RESUMO

The asymmetric total syntheses of (+)-vulgarisins A-E, which share a rare and highly oxygenated [5-6-4-5] tetracyclic core structure that were isolated from P. vulgaris Linn., have been described for the first time in a divergent manner. Key transformations include: 1) a catalytic asymmetric intramolecular cyclopropanation to forge the A ring bearing desired stereochemistry at C14; 2) a one-pot borylation/conjugate addition process for creation of the C1-C11 bond; 3) a Wolff ring contraction to assemble the bicyclo[3.2.0]heptane subunit (CD rings); and 4) a stereocontrolled pinacol cyclization for construction of the central B ring of the natural products.

4.
Hum Vaccin Immunother ; 18(6): 2135929, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36441137

RESUMO

Previous phase I to III clinical trials have shown that the inactivated SARS-CoV-2 vaccine namely CoronaVac has good efficacy, safety, and immunogenicity. This phase IV trial aims to evaluate the lot-to-lot consistency, immunogenicity, and safety on a commercial scale in healthy adults, which could provide data to support stable manufacturing. In this single-center, randomized, double-blind study, 1,080 healthy adults aged 26-45 years were randomly assigned into three groups to receive one of three lots of vaccines. All subjects received two doses of CoronaVac with an interval of 28 days. Serum samples were collected before the first dose and 28 days after the second dose to assess the immunogenicity. Solicited local and systemic adverse events (AEs) within 7 days and unsolicited AEs within 28 days after each dose of vaccination were recorded. A total of 1,039 participants completed the study and were included in the per-protocol set (PPS). The GMTs were 75.2 (68.5,82.6), 65.0 (59.0,71.7), and 65.3 (59.4,71.8), respectively, and the seroconversion rates of neutralizing antibody were all higher than 98%. The GMT ratios of each pair of lots were 1.16 (1.01,1.32), 1.15 (1.01, 1.32), and 0.99 (0.87, 1.14), respectively, meeting the immunological equivalence criteria. The incidence rates of adverse reactions (ARs) were 19.17%, 13.89%, and 18.33%, with no statistical difference. The ARs were all in grade 1 and grade 2, with incidences of 15.46% and 2.50%. Non-vaccine-related serious adverse events (SAEs) were reported. These results showed robust lot-to-lot consistency, immunogenicity, and safety. The stable production indicated that CoronaVac is suitable for large-scale use.Trial registration number: NCT04894227 (ClinicalTrials.gov).


Assuntos
Vacinas contra COVID-19 , COVID-19 , Adulto , Humanos , Vacinas contra COVID-19/efeitos adversos , Método Duplo-Cego , SARS-CoV-2 , COVID-19/prevenção & controle , Vacinas de Produtos Inativados/efeitos adversos , Anticorpos Neutralizantes , Imunogenicidade da Vacina , Anticorpos Antivirais
5.
Cell Death Discov ; 8(1): 335, 2022 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-35871166

RESUMO

Liver metastasis is the leading cause of death in colorectal carcinoma (CRC). However, little is known about the mechanisms of transferring effector messages between the primary tumor and the site of metastasis. Exosomes provide a novel transfer message method, and exosomal circular RNAs (circRNAs) play critical regulatory roles in cancer biology. In this study, the results showed that the expression of circPABPC1 was aberrantly upregulated in CRC tissues and exosomes. Exosomal circPABPC1 was considered an oncogene by functional experimental analysis in vitro and in vivo. Mechanistically, circPABPC1 recruited KDM4C to the HMGA2 promoter, reduced its H3K9me3 modification and initiated the transcription process in the nucleus. Moreover, cytoplasmic circPABPC1 promoted CRC progression by protecting ADAM19 and BMP4 from miR-874-/miR-1292-mediated degradation. Our findings indicated that exosomal circPABPC1 is an essential regulator in CRC liver metastasis progression by promoting HMGA2 and BMP4/ADAM19 expression. CircPABPC1 is expected to be a novel biomarker and antimetastatic therapeutic target in CRC.

6.
Chin Med J (Engl) ; 135(7): 799-805, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35671181

RESUMO

BACKGROUND: The new emerging avian influenza A H7N9 virus, causing severe human infection with a mortality rate of around 41%. This study aims to provide a novel treatment option for the prevention and control of H7N9. METHODS: H7 hemagglutinin (HA)-specific B cells were isolated from peripheral blood plasma cells of the patients previously infected by H7N9 in Jiangsu Province, China. The human monoclonal antibodies (mAbs) were generated by amplification and cloning of these HA-specific B cells. First, all human mAbs were screened for binding activity by enzyme-linked immunosorbent assay. Then, those mAbs, exhibiting potent affinity to recognize H7 HAs were further evaluated by hemagglutination-inhibiting (HAI) and microneutralization in vitro assays. Finally, the lead mAb candidate was selected and tested against the lethal challenge of the H7N9 virus using murine models. RESULTS: The mAb 6-137 was able to recognize a panel of H7 HAs with high affinity but not HA of other subtypes, including H1N1 and H3N2. The mAb 6-137 can efficiently inhibit the HA activity in the inactivated H7N9 virus and neutralize 100 tissue culture infectious dose 50 (TCID50) of H7N9 virus (influenza A/Nanjing/1/2013) in vitro, with neutralizing activity as low as 78 ng/mL. In addition, the mAb 6-137 protected the mice against the lethal challenge of H7N9 prophylactically and therapeutically. CONCLUSION: The mAb 6-137 could be an effective antibody as a prophylactic or therapeutic biological treatment for the H7N9 exposure or infection.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Subtipo H7N9 do Vírus da Influenza A , Vacinas contra Influenza , Influenza Aviária , Influenza Humana , Animais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais , Hemaglutininas , Humanos , Vírus da Influenza A Subtipo H3N2 , Influenza Humana/prevenção & controle , Camundongos
7.
J Am Chem Soc ; 144(6): 2495-2500, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35112847

RESUMO

A hydrogen atom transfer (HAT)-initiated Dowd-Beckwith rearrangement reaction was developed, which enables the efficient assembly of diversely functionalized polyquinane frameworks. By incorporation of an iridium-catalyzed regio- and enantioselective hydrogenation and a diastereocontrolled ODI-[5+2] cycloaddition/pinacol rearrangement cascade reaction, the asymmetric total syntheses of eight tetraquinane natural products, including (-)-crinipellins A-F and (-)-dihydrocrinipellins A and B, have been achieved in a concise and divergent manner.

8.
J Infect Dis ; 225(10): 1701-1709, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-34958382

RESUMO

BACKGROUND: Control of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic needs effective vaccines. METHODS: In a phase 2 randomized, double-blind, placebo-controlled trial, 500 adults aged 18-59 years or ≥60 years were randomized in 2:2:1 ratio to receive 3 doses of 5 µg or 10 µg of a SARS-CoV-2 inactivated vaccine, or placebo separated by 28 days. Adverse events (AEs) were recorded through day 28 after each dosing. Live virus or pseudovirus neutralizing antibodies, and receptor binding domain immunoglobulin G (RBD-IgG) antibody were tested after the second and third doses. RESULTS: Two doses of the vaccine elicited geometric mean titers (GMTs) of 102-119, 170-176, and 1449-1617 for the 3 antibodies in younger adults. Pseudovirus neutralizing and RBD-IgG GMTs were similar between older and younger adults. The third dose slightly (<1.5 fold) increased GMTs. Seroconversion percentages were 94% or more after 2 doses, which were generally similar after 3 doses. The predominant AEs were injection-site pain. All the AEs were grade 1 or 2 in intensity. No serious AE was deemed related to study vaccination. CONCLUSIONS: Two doses of this vaccine induced robust immune response and had good safety profile. A third dose given 28 days after the second dose elicited limited boosting antibody response.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Imunogenicidade da Vacina , Adolescente , Adulto , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/imunologia , Método Duplo-Cego , Humanos , Imunoglobulina G/sangue , Pessoa de Meia-Idade , SARS-CoV-2 , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , Adulto Jovem
9.
Org Lett ; 23(17): 6745-6749, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34402626

RESUMO

A metal- and hypervalent iodine reagent-free electrochemical oxidative dearomatization-induced [5+2] cycloaddition/pinacol rearrangement cascade reaction was described. The electrosynthetic method showed strong tolerance for vinylphenols, ethynylphenols, and allenylphenols, which thus enabled the rapid assembly of diversely functionalized bicyclo[3.2.1]octanes in 41-95% yields and up to >20:1 dr. This protocol could be scaled up to gram amounts and should find wide application in complex natural product synthesis.

10.
Hum Vaccin Immunother ; 17(9): 3162-3168, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-33945439

RESUMO

Background: To evaluate the persistence of antibody for 10 years, and investigate the effect of one or two booster doses with Kanghua human diploid cells rabies vaccine (HDCV) in China.Methods: Participants were re-recruited at year 10 post the primary phase 3 clinical study. Some of them in Kanghua HDCV group who had been boosted one dose at year 8, received one more dose at this boosted study. Participants who never boosted were randomly assigned to boost 1 or 2 doses of Kanghua HDCV. Blood samples were collected at day 0, 1, 3, 7, and 14. Safety was evaluated from day 0-14.Results: At year 10 after primary vaccination, the seroconversion rates of neutralizing antibody were 98.28-100% in Kanghua and Pasteur groups.After booster, the seroconversion rate in each group reached to 100% from day 7 to day 14. GMCs were similar in the groups with the same booster doses, and two doses of booster induced higher levels of antibody. The reported rates of solicited local and systemic adverse reaction were low, and no serious adverse events were found through the boosted study.Conclusion: 5 doses of Kanghua HDCV maintained long-term immunity at least 10 years. One or two doses of booster, rapidly triggered 100% protection against rabies virus.Trial registration: ClinicalTrials.gov: NCT03774628.


Assuntos
Vacina Antirrábica , Raiva , Anticorpos Antivirais , Diploide , Humanos , Imunização Secundária , Raiva/prevenção & controle , Vacinação
11.
Bioresour Technol ; 335: 125290, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34023662

RESUMO

Macroalgal biomass is currently considered as a potential candidate for biofuel production. In this study, the effects of pretreatment method and heat shock protein overexpression were investigated for efficient butanol production from Saccharina japonica using engineered Clostridium tyrobutyricum. First, various pretreatment methods including acid hydrolysis, acid hydrolysis and enzymatic saccharification, and ultrasonic-assisted acid hydrolysis were employed to obtain the fermentable sugars, and the resulted hydrolysates were evaluated for butanol fermentation. The results showed that ultrasonic-assisted acid hydrolysate obtained the highest butanol yield (0.26 g/g) and productivity (0.19 g/L⋅h). Then, the effects of homologous or heterologous heat shock protein overexpression on butanol production and tolerance were examined. Among all the engineered strains, Ct-pMA12G exhibited improved butanol tolerance and enhanced butanol production (12.15 g/L butanol with a yield of 0.34 g/g and productivity of 0.15 g/L⋅h) from 1.8-fold concentrated S. japonica hydrolysate, which was the highest level ever reported for macroalgal biomass.


Assuntos
Clostridium tyrobutyricum , 1-Butanol , Butanóis , Fermentação , Proteínas de Choque Térmico , Hidrólise
12.
Chin Med J (Engl) ; 134(11): 1289-1298, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33928916

RESUMO

BACKGROUND: The significant morbidity and mortality resulted from the infection of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) call for urgent development of effective and safe vaccines. We report the immunogenicity and safety of an inactivated SARS-CoV-2 vaccine, KCONVAC, in healthy adults. METHODS: Phase 1 and phase 2 randomized, double-blind, and placebo-controlled trials of KCONVAC were conducted in healthy Chinese adults aged 18 to 59 years. The participants in the phase 1 trial were randomized to receive two doses, one each on Days 0 and 14, of either KCONVAC (5 or 10 µg/dose) or placebo. The participants in the phase 2 trial were randomized to receive either KCONVAC (at 5 or 10 µg/dose) or placebo on Days 0 and 14 (0/14 regimen) or Days 0 and 28 (0/28 regimen). In the phase 1 trial, the primary safety endpoint was the proportion of participants experiencing adverse reactions/events within 28 days following the administration of each dose. In the phase 2 trial, the primary immunogenicity endpoints were neutralization antibody seroconversion and titer and anti-receptor-binding domain immunoglobulin G seroconversion at 28 days after the second dose. RESULTS: In the phase 1 trial, 60 participants were enrolled and received at least one dose of 5-µg vaccine (n = 24), 10-µg vaccine (n = 24), or placebo (n = 12). In the phase 2 trial, 500 participants were enrolled and received at least one dose of 5-µg vaccine (n = 100 for 0/14 or 0/28 regimens), 10-µg vaccine (n = 100 for each regimen), or placebo (n = 50 for each regimen). In the phase 1 trial, 13 (54%), 11 (46%), and seven (7/12) participants reported at least one adverse event (AE) after receiving 5-, 10-µg vaccine, or placebo, respectively. In the phase 2 trial, 16 (16%), 19 (19%), and nine (18%) 0/14-regimen participants reported at least one AE after receiving 5-, 10-µg vaccine, or placebo, respectively. Similar AE incidences were observed in the three 0/28-regimen treatment groups. No AEs with an intensity of grade 3+ were reported, expect for one vaccine-unrelated serious AE (foot fracture) reported in the phase 1 trial. KCONVAC induced significant antibody responses; 0/28 regimen showed a higher immune responses than that did 0/14 regimen after receiving two vaccine doses. CONCLUSIONS: Both doses of KCONVAC are well tolerated and able to induce robust immune responses in healthy adults. These results support testing 5-µg vaccine in the 0/28 regimen in an upcoming phase 3 efficacy trial. TRIAL REGISTRATION: http://www.chictr.org.cn/index.aspx (No. ChiCTR2000038804, http://www.chictr.org.cn/showproj.aspx?proj=62350; No. ChiCTR2000039462, http://www.chictr.org.cn/showproj.aspx?proj=63353).


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Vacinas contra COVID-19 , Método Duplo-Cego , Humanos , Vacinas de Produtos Inativados/efeitos adversos
13.
Acc Chem Res ; 54(4): 875-889, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33508196

RESUMO

Tetracyclic diterpenoids (C20) mainly refer to the plant terpenoids bearing biogenetically related carbon skeletons derived from copalyl diphosphates (ent-CPP and syn-CPP). This large family contains over 1600 known members that can be categorized into 11 major structural types. Among them, more than three-quarters share a bridged bicyclo[3.2.1]octane subunit, which is also an important branching point in biosynthesis en route to the other types of bicyclic scaffolds, such as bicyclo[2.2.2]-, bicyclo[3.3.0]-, and tricyclo[3.2.1.0]octanes. Combined with the significance of its stereochemical importance in biological activity, the assembly of the bicyclo[3.2.1]octane skeletons is critical to the success of the whole synthesis blueprint toward tetracyclic diterpenoids. Although a number of inspiring methodologies have been disclosed, general approaches by the incorporation of innovative cascade reactions permitting access to diverse structural types of tetracyclic diterpenoids remain limited and in urgent demand.Because of the long-standing interest in the synthesis of bridged diterpenoids, we have recently developed two complementary types of oxidative dearomatization induced (ODI) cascade approaches to the rapid and efficient construction of bicyclo[3.2.1]octane skeletons. In this Account, we summarize our original synthesis design, methodology development, and the application of these two strategies in tetracyclic diterpenoid synthesis during the past few years in our laboratory.First, we detail our preliminary investigation of the ODI-[5 + 2] cycloaddition/pinacol rearrangement cascade reaction, which showed a wide scope of vinylphenol substrates and led to cyclopentane and cyclohexane-fused bicyclo[3.2.1]octanes in good yields with excellent dr values. Next, we describe the utilization of this ODI-[5 + 2] cascade reaction which resulted in the asymmetric total syntheses of four highly oxygenated ent-kauranoids. The strategy concerning accurate stereochemical control in the ODI-[5 + 2] cycloaddition was then successfully transplanted to the total syntheses of three stemaranoids, thus providing a straightforward and diastereoselective route to C9-ethano-bridged tetracyclic diterpenoids. To access more complex diterpenoid rhodomollanol A, we exploited two additional biomimetic rearrangements, namely, the retro-Dieckmann fragmentation/vinylogous Dieckmann cyclization cascade and the photo-Nazarov cyclization/intramolecular cycloetherification cascade. Taken together with the ODI-[5 + 2] cascade, the asymmetric total synthesis of the target molecule was realized, which shed light on the biogenetic pathway of the unprecedented rhodomollane-type carbon framework. Finally, we describe an ODI-Diels-Alder/Beckwith-Dowd cascade approach as a valuable supplement to the ODI-[5 + 2] cascade for the fabrication of cycloheptane-fused bicyclo[3.2.1]octane skeletons. Its versatility was also demonstrated by the total syntheses of two challenging grayanane diterpenoids. In view of the high functional-group compatibility and scalability, we anticipate that the two novel cascade approaches will find further use in the field of complex natural product synthesis.


Assuntos
Compostos Bicíclicos com Pontes/química , Diterpenos/síntese química , Octanos/química , Reação de Cicloadição , Diterpenos/química , Diterpenos do Tipo Caurano/síntese química , Diterpenos do Tipo Caurano/química , Desenho de Fármacos , Oxirredução
14.
Exp Ther Med ; 21(2): 145, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33456512

RESUMO

Noncoding RNAs (ncRNAs) are involved in the pathological processes of various diseases. The aim of the present study was to verify the expression levels and the diagnostic value of two candidate ncRNAs in the blood leukocytes of patients with gestational diabetes mellitus (GDM) compared to healthy controls. The long ncRNA paired box 8 antisense 1 (Pax8-AS1) and the microRNA miR-4646 were selected, which were identified to be associated with GDM by bioinformatics analysis of a dataset from the Gene Expression Omnibus GEO database. By using reverse transcription-quantitative PCR, the expression levels of Pax8-AS1 and miR-4646 were analysed in leukocytes of patients with GDM (n=35) and normal pregnant females (n=35). The results indicated a significant decrease in the expression levels of both Pax8-AS1 and miR-4646 in patients with GDM as compared with those in the healthy controls. In the second trimester, a strong negative correlation between Pax8-AS1/miR-4646 and 2-h glucose levels was detected in patients with GDM. Receiver operating characteristic curve analysis indicated that the levels of Pax8-AS1 and miR-4646 in the second trimester of pregnancy had a significant diagnostic value with high selectivity and specificity for GDM (area under the curve values, 0.902 and 0.891, respectively; P<0.001). Overall, the present study suggested that Pax8-AS1 and miR-4646 may serve as promising diagnostic biomarkers for GDM.

15.
Epigenetics Chromatin ; 13(1): 35, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32933557

RESUMO

BACKGROUND: Gametes are highly differentiated cells specialized to carry and protect the parental genetic information. During male germ cell maturation, histone proteins undergo distinct changes that result in a highly compacted chromatin organization. Technical difficulties exclude comprehensive analysis of precise histone mutations during mammalian spermatogenesis. The model organism Saccharomyces cerevisiae possesses a differentiation pathway termed sporulation which exhibits striking similarities to mammalian spermatogenesis. This study took advantage of this yeast pathway to first perform systematic mutational and proteomics screens on histones, revealing amino acid residues which are essential for the formation of spores. METHODS: A systematic mutational screen has been performed on the histones H2A and H2B, generating ~ 250 mutants using two genetic backgrounds and assessing their ability to form spores. In addition, histones were purified at key stages of sporulation and post-translational modifications analyzed by mass spectrometry. RESULTS: The mutation of 75 H2A H2B residues affected sporulation, many of which were localized to the nucleosome lateral surface. The use of different genetic backgrounds confirmed the importance of many of the residues, as 48% of yeast histone mutants exhibited impaired formation of spores in both genetic backgrounds. Extensive proteomic analysis identified 67 unique post-translational modifications during sporulation, 27 of which were previously unreported in yeast. Furthermore, 33 modifications are located on residues that were found to be essential for efficient sporulation in our genetic mutation screens. The quantitative analysis of these modifications revealed a massive deacetylation of all core histones during the pre-meiotic phase and a close interplay between H4 acetylation and methylation during yeast sporulation. Methylation of H2BK37 was also identified as a new histone marker of meiosis and the mouse paralog, H2BK34, was also enriched for methylation during meiosis in the testes, establishing conservation during mammalian spermatogenesis. CONCLUSION: Our results demonstrate that a combination of genetic and proteomic approaches applied to yeast sporulation can reveal new aspects of chromatin signaling pathways during mammalian spermatogenesis.


Assuntos
Evolução Molecular , Gametogênese , Código das Histonas , Meiose , Animais , Epigênese Genética , Histonas/química , Histonas/metabolismo , Metilação , Camundongos , Processamento de Proteína Pós-Traducional , Proteoma/genética , Proteoma/metabolismo , Saccharomyces cerevisiae , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Esporos Fúngicos/fisiologia
16.
Vaccine ; 38(37): 5940-5946, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32732142

RESUMO

Inactivated quadrivalent influenza vaccine (IIV4) containing two influenza A strains (H1N1 and H3N2) and one strain from each B lineage (Victoria and Yamagata) may offer broader protection against seasonal influenza. This study examined the immunogenicity and safety of a candidate IIV4. A randomized, double-blind, controlled phase III clinical trial was conducted in healthy subjects aged ≥3 years. Subjects were randomly assigned into three groups in a 2:1:1 ratio, receiving single dose of IIV4 or inactivated trivalent influenza vaccine (IIV3) which contains either B/Victoria strain (BV) or B/Yamagata strain (BY). Blood samples were collected before and 28 days after vaccination to test hemagglutination inhibition (HI) antibodies of the four influenza strains. Safety information was collected for 28 days after vaccination. A total of 2320 subjects (IIV4: 1160, IIV3-BV: 580, IIV3-BY: 580) were enrolled in this study. After vaccination, the seroconversion rates of IIV4 against H1N1, H3N2, BV and BY strains were 77.15%, 81.93%, 60.14% and 64.57%, respectively. Geometric mean titers (GMTs) against the four influenza strains were 523.91, 274.13, 115.35 and 257.81, respectively. The investigational IIV4 was non-inferiority to IIV3 for the four strains, meanwhile superior to IIV3 for additional B strains (B/BV, B/BY). For safety, there had no significant difference in the incidence of the adverse reactions among the three groups (P = 0.5986). No serious adverse events related to vaccination occurred. The IIV4 had good immunogenicity and safety, which added an influenza B protection with no increased safety concerns. (ClinicalTrials.gov number: NCT03853993).


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Anticorpos Antivirais , Pré-Escolar , Método Duplo-Cego , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Testes de Inibição da Hemaglutinação , Humanos , Imunogenicidade da Vacina , Vírus da Influenza A Subtipo H3N2 , Vacinas contra Influenza/efeitos adversos , Influenza Humana/prevenção & controle , Vacinas de Produtos Inativados/efeitos adversos
17.
Hum Vaccin Immunother ; 16(7): 1579-1585, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32209003

RESUMO

Enterovirus 71 (EV71) is the dominant pathogen in severe and fatal hand-foot-mouth disease (HFMD) cases. Since 2015, three inactivated EV71 vaccines have been approved in China. The vaccination coverage of the EV71 vaccine has been relatively low, especially in rural areas. A cross-sectional survey from July 19 to August 22, 2018, was conducted in three rural counties of northern Jiangsu Province among parents of children aged 6-60 months. We adopted a pretested validated questionnaire to assess knowledge, awareness, and attitude of HFMD and EV71 vaccines among respondents and used univariate and multivariate binary logistic analyses to explore potential factors associated with the acceptance of EV71 vaccines. Of the 1,112 parents who participated, 87.8% were willing to vaccinate their children with EV71 vaccines. Parents over 40 y old were less likely to have their children vaccinated [adjusted odds ratio (aOR) = 2.12, 95% confidence interval (CI): 1.13-3.97]. Parents who lived in Ganyu (aOR = 0.50, 95% CI: 0.31-0.79) or Xinyi county (aOR = 0.33, 95% CI: 0.20-0.53), had a university or higher degree (aOR = 0.26, 95% CI: 0.11-0.64), had good knowledge of EV71 vaccines (aOR = 0.81, 95% CI: 0.67-0.98), perceived their children's disease susceptibility, and worried about the severity of HFMD had a higher willingness to vaccinate their children. Most parents were willing to vaccinate their children against EV71-related HFMD. Parental age, location, education level, knowledge of EV71 vaccines, concern about susceptibility, and severity of HFMD were all factors that influenced willingness to vaccinate.


Assuntos
Enterovirus Humano A , Enterovirus , Doença de Mão, Pé e Boca , Criança , Pré-Escolar , China , Estudos Transversais , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/prevenção & controle , Humanos , Lactente , Pais , Cobertura Vacinal , Vacinas de Produtos Inativados
18.
Org Lett ; 22(4): 1426-1430, 2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-32003567

RESUMO

An asymmetric and efficient approach for the total syntheses of (+)-stemarin and the proposed structures of stemara-13(14)-en-18-ol and stemara-13(14)-en-17-acetoxy-18-ol are described. The key features of the strategy include a Lewis acid-induced cationic polyene cyclization and an ODI-[5+2] cycloaddition/pinacol-type 1,2-acyl migration cascade.

19.
Bioresour Technol ; 301: 122764, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31958691

RESUMO

The sucrose metabolic genes (scrA, scrB and scrK) from C. acetobutylicum ATCC 824 were successfully overexpressed in C. tyrobutyricum ATCC 25755, endowing it with the ability to co-utilize sucrose, fructose and glucose in the cane molasses. As a result, the engineering strain C. tyrobutyricum ATCC 25755/scrBAK produced 18.07 g/L and 18.98 g/L butyric acid when sucrose and cane molasses were used as the carbon source, respectively. Furthermore, the medium composition and initial cane molasses concentration were optimized to make full use of the untreated cane molasses. Based on these results, 45.71 g/L butyric acid with a yield of 0.39 g/g was obtained in fed-batch fermentation, and the feedstock cost of using untreated cane molasses was decreased by ~47% when compared with the conventional glucose fermentation. This study demonstrated the potential application of C. tyrobutyricum ATCC 25755/scrBAK for economic butyric acid production from untreated cane molasses.


Assuntos
Clostridium tyrobutyricum , Ácido Butírico , Bengala , Fermentação , Melaço
20.
Biotechnol Biofuels ; 12: 214, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31528202

RESUMO

BACKGROUND: As a renewable and clean energy carrier, the production of biohydrogen from low-value feedstock such as lignocellulose has increasingly garnered interest. The NADH-dependent reduced ferredoxin:NADP+ oxidoreductase (NfnAB) complex catalyzes electron transfer between reduced ferredoxin and NAD(P)+, which is critical for production of NAD(P)H-dependent products such as hydrogen and ethanol. In this study, the effects on end-product formation of deletion of nfnAB from Thermoanaerobacterium aotearoense SCUT27 were investigated. RESULTS: Compared with the parental strain, the NADH/NAD+ ratio in the ∆nfnAB mutant was increased. The concentration of hydrogen and ethanol produced increased by (41.1 ± 2.37)% (p < 0.01) and (13.24 ± 1.12)% (p < 0.01), respectively, while the lactic acid concentration decreased by (11.88 ± 0.96)% (p < 0.01) when the ∆nfnAB mutant used glucose as sole carbon source. No obvious inhibition effect was observed for either SCUT27 or SCUT27/∆nfnAB when six types of lignocellulose hydrolysate pretreated with dilute acid were used for hydrogen production. Notably, the SCUT27/∆nfnAB mutant produced 190.63-209.31 mmol/L hydrogen, with a yield of 1.66-1.77 mol/mol and productivity of 12.71-13.95 mmol/L h from nonsterilized rice straw and corn cob hydrolysates pretreated with dilute acid. CONCLUSIONS: The T. aotearoense SCUT27/∆nfnAB mutant showed higher hydrogen yield and productivity compared with those of the parental strain. Hence, we demonstrate that deletion of nfnAB from T. aotearoense SCUT27 is an effective approach to improve hydrogen production by redirecting the electron flux, and SCUT27/∆nfnAB is a promising candidate strain for efficient biohydrogen production from lignocellulosic hydrolysates.

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