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1.
Proc Natl Acad Sci U S A ; 120(45): e2205463120, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37917793

RESUMO

Zero-knowledge proof (ZKP) is a fundamental cryptographic primitive that allows a prover to convince a verifier of the validity of a statement without leaking any further information. As an efficient variant of ZKP, noninteractive zero-knowledge proof (NIZKP) adopting the Fiat-Shamir heuristic is essential to a wide spectrum of applications, such as federated learning, blockchain, and social networks. However, the heuristic is typically built upon the random oracle model that makes ideal assumptions about hash functions, which does not hold in reality and thus undermines the security of the protocol. Here, we present a quantum solution to the problem. Instead of resorting to a random oracle model, we implement a quantum randomness service. This service generates random numbers certified by the loophole-free Bell test and delivers them with postquantum cryptography (PQC) authentication. By employing this service, we conceive and implement NIZKP of the three-coloring problem. By bridging together three prominent research themes, quantum nonlocality, PQC, and ZKP, we anticipate this work to inspire more innovative applications that combine quantum information science and the cryptography field.

2.
BMC Infect Dis ; 24(1): 571, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851671

RESUMO

OBJECTIVE: In this study, we examined the value of chest CT signs combined with peripheral blood eosinophil percentage in differentiating between pulmonary paragonimiasis and tuberculous pleurisy in children. METHODS: Patients with pulmonary paragonimiasis and tuberculous pleurisy were retrospectively enrolled from January 2019 to April 2023 at the Kunming Third People's Hospital and Lincang People's Hospital. There were 69 patients with pulmonary paragonimiasis (paragonimiasis group) and 89 patients with tuberculous pleurisy (tuberculosis group). Clinical symptoms, chest CT imaging findings, and laboratory test results were analyzed. Using binary logistic regression, an imaging model of CT signs and a combined model of CT signs and eosinophils were developed to calculate and compare the differential diagnostic performance of the two models. RESULTS: CT signs were used to establish the imaging model, and the receiver operating characteristic (ROC) curve was plotted. The area under the curve (AUC) was 0.856 (95% CI: 0.799-0.913), the sensitivity was 66.7%, and the specificity was 88.9%. The combined model was established using the CT signs and eosinophil percentage, and the ROC was plotted. The AUC curve was 0.950 (95% CI: 0.919-0.980), the sensitivity was 89.9%, and the specificity was 90.1%. The differential diagnostic efficiency of the combined model was higher than that of the imaging model, and the difference in AUC was statistically significant. CONCLUSION: The combined model has a higher differential diagnosis efficiency than the imaging model in the differentiation of pulmonary paragonimiasis and tuberculous pleurisy in children. The presence of a tunnel sign on chest CT, the absence of pulmonary nodules, and an elevated percentage of peripheral blood eosinophils are indicative of pulmonary paragonimiasis in children.


Assuntos
Eosinófilos , Paragonimíase , Tomografia Computadorizada por Raios X , Tuberculose Pleural , Humanos , Paragonimíase/diagnóstico , Paragonimíase/diagnóstico por imagem , Masculino , Feminino , Criança , Estudos Retrospectivos , Diagnóstico Diferencial , Tuberculose Pleural/diagnóstico , Pré-Escolar , Adolescente , Curva ROC , Sensibilidade e Especificidade
3.
J Org Chem ; 88(6): 3772-3780, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36877592

RESUMO

A novel multicomponent sulfonylation of alkenes is described for the assembly of various ß-substituted arylsulfones using cheap and easily available K2S2O5 as a sulfur dioxide source. Of note, the procedure does not need any extra oxidants and metal catalysts and exhibits a relatively wide substrate scope and good functional group compatibility. Mechanistically, an initial arylsulfonyl radical is formed involving the insertion of sulfur dioxide with aryl diazonium salt, followed by alkoxyarylsulfonylation or hydroxysulfonylation of alkenes.

4.
J Org Chem ; 87(18): 12265-12273, 2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-36037316

RESUMO

A novel copper-catalyzed cross-coupling of arylsulfonyl radicals with diazo compounds is described for the synthesis of various arylsulfones under mild conditions. In this reaction, the cheap, environmentally friendly, and readily available inorganic K2S2O5 is employed as the sulfur dioxide source for providing arylsulfonyl radicals. In addition, a radical mechanism involving the insertion of sulfur dioxide with aryl radicals followed by the coupling of arylsulfonyl radicals with copper carbenes is proposed.


Assuntos
Cobre , Dióxido de Enxofre , Compostos Azo , Catálise , Estrutura Molecular
5.
J Org Chem ; 87(5): 2740-2747, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-35089023

RESUMO

A novel and mild metal-free catalyzed radical-mediated cascade spirocyclization of N-benzylacrylamides with polyhaloalkanes is proposed for the preparation of polyhalo-substituted azaspirocyclohexadienones. Notably, polyhaloalkanes are employed as efficient alkyl radical sources via the cleavage of C(sp3)-H bonds. This protocol undergoes a cascade radical addition and intramolecular cyclization/dearomatization process, and enables the easy construction of multiple chemical bonds and a spiro ring in a single reaction.


Assuntos
Compostos de Espiro , Ciclização , Radicais Livres , Compostos de Espiro/química
6.
Opt Express ; 29(16): 25859-25867, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34614905

RESUMO

Quantum key distribution (QKD) provides information theoretically secure key exchange requiring authentication of the classic data processing channel via pre-sharing of symmetric private keys to kick-start the process. In previous studies, the lattice-based post-quantum digital signature algorithm Aigis-Sig, combined with public-key infrastructure (PKI), was used to achieve high-efficiency quantum security authentication of QKD, and we have demonstrated its advantages in simplifying the MAN network structure and new user entry. This experiment further integrates the PQC algorithm into the commercial QKD system, the Jinan field metropolitan QKD network comprised of 14 user nodes and 5 optical switching nodes, and verifies the feasibility, effectiveness and stability of the post-quantum cryptography (PQC) algorithm and advantages of replacing trusted relays with optical switching brought by PQC authentication large-scale metropolitan area QKD network. QKD with PQC authentication has potential in quantum-secure communications, specifically in metropolitan QKD networks.

7.
J Dairy Sci ; 101(10): 8767-8777, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30100502

RESUMO

Pathogens, mycotoxins, or antibiotics may exist in a food sample. Micro- and macromolecular substances must be detected quickly. A rapid and convenient lateral flow immunoassay (LFI) integrated with competitive and sandwich models was developed to detect micro- and macromolecular substances. In this study, aflatoxin M1 (AFM1) and Escherichia coli O157:H7 were selected as the micro- and macromolecular substances, respectively. Two test lines in the LFI test strip were evaluated to detect AFM1 and E. coli O157:H7 by competitive and sandwich models. Results showed that the limits of detection for detecting AFM1 and E. coli O157:H7 were 50 pg·mL-1 and 1.58 × 104 cfu·mL-1, respectively. The whole assay time was 30 min. The recoveries of gold nanoparticle-LFI ranged from 78.0 to 111.6% with coefficients of variation in the range of 3.9 to 8.5% for the detection of AFM1. For the detection of E. coli O157:H7, the range of recoveries was from 70.1 to 89.6% with coefficients of variation ranging from 4.9 to 13.0%. This study not only tested sensitivity and specificity, but also was a systematic study of location of 2 test lines of the LFI test strip integrated with competitive and sandwich models.


Assuntos
Aflatoxina M1/isolamento & purificação , Escherichia coli O157/isolamento & purificação , Imunoensaio/métodos , Leite/química , Leite/microbiologia , Animais , Microbiologia de Alimentos , Ouro , Nanopartículas Metálicas
8.
Org Lett ; 26(33): 6983-6987, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39140705

RESUMO

A novel Fe-catalyzed fluorosulfonylation of alkenes with Na2S2O4 and N-fluorobenzenesulfonimide (NFSI) for assembling various lactam-functionalized alkyl sulfonyl fluorides is disclosed. In this reaction, Na2S2O4 acts as both an SO2 source and a reductant. Furthermore, the resulting products can be efficiently transformed into valuable chemicals, including sulfonyl esters and sulfonamides, via the sulfur(VI) fluoride exchange (SuFEx) click reaction. Preliminary mechanistic studies suggest that the transformation proceeds through intramolecular radical cyclization, SO2 insertion, sulfite anion formation, and fluorination.

9.
Org Lett ; 25(31): 5817-5821, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37498112

RESUMO

A Pd-catalyzed multicomponent cross-coupling of allyl esters with alkyl bromides to synthesize allylic sulfones by using K2S2O5 as a connector is first reported. The reaction displays a broad range of substrate generality along with excellent functional group compatibility and produces the products with high regioselectivity (only E). Furthermore, the biologically active molecules with a late-stage modification, including aspirin, menthol, borneol, and estrone, are also highly compatible with the multicomponent cross-coupling reaction. Mechanistic studies indicate that the process of SO2 insertion into the C-Pd bond was involved in this transformation.

10.
Food Chem ; 257: 382-387, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29622226

RESUMO

Amantadine (AMD), a banned antiviral veterinary drug, is still being abused. This study developed a novel enzyme linked immunosorbent assay for the colorimetric detection of AMD involving DNA hybridization reaction and non-crosslinking gold nanoparticles (AuNPs) aggregation. Accordingly, the Primer 1-AuNPs-anti-AMD monoclonal antibody (mAb) could be captured by AMD artificial antigen on ELISA wells. Primer 2, which was complementary paired to Primer 1, was eventually added into the ELISA wells. After the hybridization reaction, the free Primer 2 in the supernatant was mixed with AuNPs and NaCl and induced a rapid color change of AuNPs. The lack of AMD in the sample resulted in capturing a substantial Primer 1-AuNPs-mAb complex and limited free Primer 2 in the supernatant. After adding NaCl, the color of AuNPs turned blue with limited Primer 2. This simple and visualized novel method had good sensitivity (0.033 µM) and exhibited a potential application for AMD screening on site.


Assuntos
Amantadina/análise , Ensaio de Imunoadsorção Enzimática/métodos , Ouro/química , Nanopartículas Metálicas/química , Amantadina/imunologia , Anticorpos Monoclonais/imunologia , Colorimetria , DNA/química , DNA/metabolismo , Hibridização de Ácido Nucleico
11.
Nan Fang Yi Ke Da Xue Xue Bao ; 35(10): 1380-3, 2015 Oct.
Artigo em Zh | MEDLINE | ID: mdl-26547327

RESUMO

OBJECTIVE: To compare the long-term outcomes of patients receiving percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG), or medical therapy for treatment of chronic total coronary occlusion (CTO). METHODS: The patients with CTO were selected from a consecutive cohort of patients who underwent coronary angiography (CAG) between 2008 and 2009. The patients with multiple CAG were excluded. The patients received treatments with PCI, CABG, or conservative medication therapy and were followed for major adverse cardiovascular events (MACE) within 5 years. RESULTS: A total of 253 patients were enrolled in this study, including 192 receiving PCI, 48 receiving CABG, and 13 treated conservatively with medications. The baseline clinical characteristics were similar among the 3 groups except for increased low-density lipoprotein (LDL) and total cholesterol (TC) in the medication group, and increased Syndax score in CABG group. During the follow-up, the incidences of MACE, AMI, death, stroke or heart failure did not differ significantly among the 3 groups (P>0.05). However, CABG group showed a higher incidence of the stroke than the other two groups although this difference did not reach a statistically significantly level (P=0.06). CONCLUSION: Our study did not demonstrate that recanalization offers greater long-term benefits than medications for treatment of CTO, and the patients receiving CABG appeared to have a higher incidence of stroke.


Assuntos
Ponte de Artéria Coronária , Oclusão Coronária/cirurgia , Oclusão Coronária/terapia , Intervenção Coronária Percutânea , Doença Crônica , Estudos de Coortes , Angiografia Coronária , Humanos , Incidência , Acidente Vascular Cerebral/epidemiologia , Resultado do Tratamento
12.
Chin Med J (Engl) ; 126(9): 1630-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23652041

RESUMO

BACKGROUND: Percutaneous coronary intervention (PCI) is indicated for angina with coronary stenosis. However, PCI for asymptomatic coronary stenosis remains controversial. We prospectively followed a group of patients for four years who underwent coronary computed tomography angiography (CCTA) for major adverse cardiac events (MACE). We hypothesized that the results of this trial would reliably reflect the natural outcome of the coronary disease. METHODS: Consecutive patients who underwent CCTA from June 2008 to May 2009 were selected. Those who could not be reached by telephone, had significant angina, had CT images that were not interpretable, or poor kidney and left ventricular (LV) function were excluded. The patients were divided into five groups: group A normal CCTA without stenosis, group B mild stenosis (1% - 49%), group C moderate stenosis (50% - 74%), group D severe stenosis (= 75%) and they were treated with optimal medical therapy (OMT) or PCI. The group E had PCI before the CCTA examination. The patients were then followed for MACE after different treatments. MACE included acute myocardial infarction (MI), heart failure (HF) and death. RESULTS: The patient population consisted of 419 patients. The follow-up time was (51 ± 5) months. The age was (60 ± 31) years. Male made up 67.78% of the population (n = 284). A total of 51 cases of MACE occurred including 25 MI, eight HF and 18 all-cause deaths. There was no MACE in group A. Although MACE occurred in two patients in group B, they were not attributed to cardiac death. We further compared the MACE in groups C-E and no significant difference was found (P > 0.05). However, a difference was detected among patients with unstable angina pectoris (UAP), stable angina pectoris (SAP), re-hospitalization, and cerebrovascular events from groups A-E (P < 0.05). The plaque scores were used to predict MACE. The scores progressively increased significantly with lesion severity (P < 0.05). Receiver operating curve (ROC) was performed to determine the sensitivity and specificity in predicting MACE. Our scores predicted MI with area of 0.76, predicted HF with area of 0.77, and predicted death with area of 0.70. CONCLUSIONS: Normal and mild lesions had very few events. With increased stenosis the MACE rate increased progressively. PCI did not significantly reduce the MACE in comparison with OMT in asymptomatic patients. Furthermore, UAP, re-hospitalization, and re-PCI were significantly increased in patients who were treated with PCI.


Assuntos
Angiografia Coronária , Estenose Coronária/terapia , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Estenose Coronária/diagnóstico por imagem , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico por imagem , Intervenção Coronária Percutânea , Estudos Prospectivos , Resultado do Tratamento
13.
Chin Med J (Engl) ; 126(8): 1509-16, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23595386

RESUMO

BACKGROUND: Recent studies showed that bone marrow-derived mesenchymal stem cells (BMSCs) had risk of ectopic bone formation. In this study, we aimed to investigate the effect of growth and differentiation factor 6 (GDF-6) on the tenogenic differentiation of BMSCs in vitro, and then combined with small intestine submucous (SIS) to promote tendon regeneration in vivo. METHODS: The BMSCs were isolated from the green fluorescent protein (GFP) rats, and were characterized by multi-differentiation assays following our previous study protocol. BMSCs cultured with different concentrations of GDF-6, without growth factors served as control. After 2 weeks, mRNA expression and protein expression of tendon specific markers were examined by qRT-PCR and Western blotting to define an optimal concentration of GDF-6. Mann-Whitney U-test was used to compare the difference in relative mRNA expression among all groups; P ≤ 0.05 was regarded as statistically significant. The GDF-6 treated BMSCs combined with SIS were implanted in nude mice and SD rat acute patellar tendon injury model, the BMSCs combined with SIS served as control. After 12 and 4 weeks in nude mice and tendon injury model, the samples were collected for histology. RESULTS: After the BMSCs were treated with different concentration of GDF-6 for 2 weeks, the fold changes of the specific markers (Tenomodulin and Scleraxis) mRNA expression were significantly higher in GDF-6 (20 ng/ml) group (P ≤ 0.05), which was also confirmed by Western blotting result. The BMSCs became parallel in orientation after GDF-6 (20 ng/ml) treatment, but the BMSCs in control group were randomly oriented. The GDF-6 (20 ng/ml) treated BMSCs were combined with SIS, and were implanted in nude mice for 12 weeks, the histology showed neo-tendon formation. In the SD rat patellar tendon window injury model, the histology also indicated the GDF-6 (20 ng/ml) treated BMSCs combined with SIS could promote tendon regeneration. CONCLUSIONS: GDF-6 has tenogenic effect on the tenogenic differentiation of BMSCs, and GDF-6 (20 ng/ml) has better tenogenic effect compared to other concentrations. The GDF-6 (20 ng/ml) treated BMSCs combined with SIS can form neo-tendons and promote tendon regeneration.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Fator 6 de Diferenciação de Crescimento/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Tendões/efeitos dos fármacos , Animais , Masculino , Proteínas de Membrana/genética , Células-Tronco Mesenquimais/citologia , Camundongos , Camundongos Nus , Ratos , Ratos Sprague-Dawley , Regeneração/efeitos dos fármacos , Tendões/fisiologia
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