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1.
Anal Chim Acta ; 1189: 339213, 2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-34815035

RESUMO

Staphylococcus aureus is a common foodborne pathogen that can cause a suppurative infection after eating contaminated food. Detection of S. aureus plays an important role in the food industry. In this study, a strategy for the detection of S. aureus using magnetic separation (MS) technology combined with rolling circle amplification (MS-RCA) was proposed. The strategy used antibiotics to capture bacteria and employed RCA products as signal output probes. Vancomycin (Van), as a commonly used antibiotic, can recognize peptidoglycan on the cell wall of Gram-positive bacteria and can effectively identify target bacteria. Therefore, we prepared BSAylated-Van functionalized magnetic beads (Van-MBs) for the pre-enrichment of S. aureus. To ensure the selectivity of this method, we used biotin-pig IgG to bind S. aureus. In addition, to amplify the output signal of the MS-RCA strategy, we introduced streptavidin (SA) and successfully obtained the Van-MBs@S. aureus@biotin-pig IgG@SA@biotin-RCA probe complex and used the biotin-avidin-system (BAS) by combining magnetic separation technology and RCA technology to realize the enrichment and specific detection of S. aureus. Furthermore, by optimizing the experimental conditions such as the magnetic separation time and the amount of Van-MBs, the detection performance of this method was improved. Under the optimal conditions, the detection limit of this method for S. aureus was 3.3 × 102 CFU/mL in fruit juice, and it was less affected by other bacteria.


Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Animais , Sucos de Frutas e Vegetais , Técnicas de Amplificação de Ácido Nucleico , Infecções Estafilocócicas/diagnóstico , Estreptavidina , Suínos , Vancomicina
2.
Talanta ; 237: 122938, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34736669

RESUMO

As one of the most common and important post-translational modifications, protein N-glycosylation plays essential roles in many biological processes and have long been considered closely correlated with the occurrence and progression of multiple diseases. Systematic characterization of these disease-related protein N-glycosylation is one of the most convenient ways for new diagnostic biomarker and therapeutic drug target discovering. However, the biological samples are extremely complex and the abundance of N-glycoproteins are especially low, which make highly efficient N-glycoprotein/glycopeptide enrichment before mass spectrometry analysis a prerequisite. In this work, a new type of hydrophilic material (GO-pDMAPS) was prepared by in situ growth of linear zwitterionic polymer chains on the surface of GO and it was successfully applied for N-glycopeptide enrichment from human urine. Due to the excellent hydrophilicity and the facilitate interactions between this GO-pDMAPS and the targets, a total of 1426 N-glycosylated sites corresponding to 766 N-glycoproteins as well as 790 N-glycosylation sites corresponding to 470 N-glycoproteins were enriched and identified from urine of healthy subjects and patients with lung adenocarcinoma, respectively. Among which, 27 N-glycoproteins were expressed exclusively and 4 N-glycoproteins were upregulated at least 3 times comparing with the healthy group, demonstrating the tremendous potential of this new hydrophilic material for large scale and in depth N-glycoproteome research.


Assuntos
Adenocarcinoma de Pulmão , Glicopeptídeos , Grafite , Voluntários Saudáveis , Humanos , Interações Hidrofóbicas e Hidrofílicas , Polímeros
3.
J Inflamm Res ; 14: 5955-5967, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803392

RESUMO

Background: It is known that osteoarthritis (OA) pathogenesis involves inflammation that drives pathologic changes and that the matricellular protein, thrombospondin-2 (TSP2), is involved in angiogenesis, carcinogenesis, and inflammation. However, how TSP2 contributes to OA inflammatory processes is unclear. Objective: The aim of current study was to elucidate whether TSP2 could promote interleukin-6 (IL-6), a pro-inflammatory cytokine, expression in osteoarthritis synovial fibroblasts (OASFs). Methods: The synovial fibroblasts isolated from osteoarthritis and healthy donors were incubated with recombinant TSP2 to evaluate its effect in OA pathogenesis. The SFs were incubated with recombinant TSP2, followed by determining the IL-6 expression by qPCR and Western blot. After SFs were incubated with TSP2 for different time interval, the Western blot was performed to investigate the activation of signal pathway. The different strategies including neutralizing antibodies, siRNAs, and chemical inhibitors were used to discover the signal transduction in response to TSP2 incubation in OASFs. To evaluate the therapeutic potential of TSP2 in osteoarthritis, the anterior cruciate ligament transection (ACLT) in SD rats was performed in the presence or absence of TSP neutralizing antibody treatment. Results: Our investigations have revealed that TSP2 promoted IL-6 expression in OASFs in a dose-dependent manner, especially in 30 and 100 ng/mL concentration (p < 0.05). Using different strategies including neutralizing antibodies, siRNAs, and chemical inhibitors, all of which attenuated signal pathway components in OASFs, we found evidence for the involvement of integrin αvß3, PI3K, Akt, and NF-κB in TSP2-mediated upregulation of IL-6 (p < 0.05). Finally, in the result of rat ACLT surgical model, we found that TSP2 neutralizing antibody had protective effects in cartilage destruction during OA progression. Conclusion: Thrombospondin-2 palys an important role in osteoarthritis pathogenesis and provides an opportunity to deal with osteoarthritis.

4.
Front Cardiovasc Med ; 8: 731844, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722665

RESUMO

Backgrounds: Influenza vaccination could decrease the risk of major cardiac events in patients with chronic obstructive pulmonary disease (COPD). However, the effects of the vaccine on decreasing the risk of ventricular arrhythmia (VA) development in such patients remain unclear. Methods: We retrospectively analyzed the data of 18,658 patients with COPD (≥55 years old) from the National Health Insurance Research Database from January 1, 2001, to December 31, 2012. After a 1:1 propensity score matching by the year of diagnosis, we divided the patients into vaccinated and unvaccinated groups. Time-varying Cox proportional hazards regression was applied to assess the time to event hazards of influenza vaccination exposure. Results: The risk of VA occurrence was significantly lower in the vaccinated group during influenza season and all seasons [adjusted hazard ratio (aHR): 0.62, 95% CI: 0.41-0.95; aHR: 0.69, 95% CI: 0.44-1.08; and aHR: 0.65, 95% CI: 0.48-0.89, in the influenza season, non-influenza season, and all seasons, respectively]. Among patients with CHA2DS2-VASc scores (conditions and characteristics included congestive heart failure, hypertension, diabetes, stroke, vascular disease, age, and sex) of 2-3, receiving one time and two to three times of influenza vaccination were associated with lower risk of VA occurrence in all seasons (aHR: 0.28, 95% CI: 0.10-0.80; aHR: 0.27, 95% CI: 0.10-0.68, respectively). Among patients without stroke, peripheral vascular disease, and diabetes, a lower risk of VA occurrence after receiving one and two to three times vaccination was observed in all seasons. Among patients with a history of asthma and patients without a history of heart failure, ischemic heart disease, angina hypertension, or renal failure, a significantly lower risk of VA occurrence was observed after the first time of vaccination in all seasons. Conclusions: Influenza vaccination may be associated with lower risks of VA among patients with COPD aged 55-74. Further investigation is still needed to resolve this clinical question.

5.
Rheumatol Ther ; 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34806155

RESUMO

INTRODUCTION: This phase III trial (NCT04178850) evaluated the efficacy, safety, and immunogenicity of GB242, an infliximab biosimilar, vs. infliximab (Remicade®) reference product in patients with moderate-to-severe active rheumatoid arthritis (RA) combination with methotrexate (MTX) therapy. METHODS: Patients were randomized in a 1:1 ratio to receive either GB242 or INF (3 mg/kg). Therapeutic equivalence of clinical response according to the American College of Rheumatology 20% (ACR20) response rate at week 30 was declared if the two-sided 95% CI for the treatment difference was within ± 14%. The comparison of GB242 with INF also included the proportion of patients achieving a week 30 ACR 50 response, ACR70 response, change in Disease Activity Score 28 (DAS28), as well as safety and immunogenicity. RESULTS: A total of 570 subjects were randomized into GB242 (N = 285) or INF (N = 285) and 283 subjects in each group were analyzed. At week 30, the ACR20 was 62.54% for the GB242 group (95% CI 56.62-68.20%) and 56.89% for the INF group (95% CI 50.90-62.74%). The difference between the two groups was 5.65% with a 95% CI of - 2.48 to 13.74. ACR50 response was 37.12% for GB242 and 32.86% for INF at week 30. ACR70 response was 19.79% for GB242 and 16.96% for INF at week 30, respectively. The incidence of treatment-emergent adverse events was comparable (77.4% in GB242 vs. 80.2% in INF) and detection of antidrug antibodies (ADA) to infliximab up to week 30 (60.8% in GB242 vs. 59.4% in INF) was comparable. CONCLUSIONS: GB242 demonstrated equivalent efficacy to INF at week 30. Moreover, GB242 was well tolerated, with a similar immunogenicity and safety profile comparable to INF.

6.
Front Oncol ; 11: 735277, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34760697

RESUMO

Osteosarcoma, a common aggressive and malignant cancer, appears in the musculoskeletal system among young adults. The major cause of mortality in osteosarcoma was the recurrence of lung metastases. However, the molecular mechanisms of metastasis involved in osteosarcomas remain unclear. Recently, CXCL1 and CXCR2 have been crucial indicators for lung metastasis in osteosarcoma by paracrine releases, suggesting the involvement of directing neutrophils into tumor microenvironment. In this study, overexpression of CXCL1 has a positive correlation with the migratory and invasive activities in osteosarcoma cell lines. Furthermore, the signaling pathway, CXCR2/FAK/PI3K/Akt, is activated through CXCL1 by promoting vascular cell adhesion molecule 1 (VCAM-1) via upregulation of nuclear factor-kappa B (NF-κB) expression and nuclear translocation. The in vivo animal model further demonstrated that CXCL1 serves as a critical promoter in osteosarcoma metastasis to the lung. The correlated expression of CXCL1 and VCAM-1 was observed in the immunohistochemistry staining from human osteosarcoma specimens. Our findings demonstrate the cascade mechanism regulating the network in lung metastasis osteosarcoma, therefore indicating that the CXCL1/CXCR2 pathway is a worthwhile candidate to further develop treatment schemas.

7.
Cell Death Dis ; 12(12): 1101, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34815382

RESUMO

Chondrosarcoma is a malignancy of soft tissue and bone that has a high propensity to metastasize to distant organs. Nerve growth factor (NGF) is critical for neuronal cell growth, apoptosis, and differentiation, and also appears to promote the progression and metastasis of several different types of tumors, although the effects of NGF upon chondrosarcoma mechanisms are not very clear. We report that NGF facilitates lysyl oxidase (LOX)-dependent cellular migration and invasion in human chondrosarcoma cells, and that NGF overexpression enhances lung metastasis in a mouse model of chondrosarcoma. NGF-induced stimulation of LOX production and cell motility occurs through the inhibition of miR-149-5p expression, which was reversed by PI3K, Akt, and mTOR inhibitors and their respective short interfering RNAs. Notably, levels of NGF and LOX expression correlated with tumor stage in human chondrosarcoma samples. Thus, NGF appears to be a worthwhile therapeutic target for metastatic chondrosarcoma.

8.
Bioorg Chem ; 118: 105471, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34798457

RESUMO

On the basis of N-(3-amino-4-methoxyphenyl)acrylamide scaffold, a series of novel compounds containing 3-substitutional-1-methyl-1H-indole, 2-substitutional pyrrole or thiophene moieties were synthesized and their in vitro antiproliferation activities against A549 and H1975 cell lines were evaluated. The results indicated that most of the compounds showed moderate to excellent antitumor activities. Especially, compounds 9a (A549 IC50 = 1.96 µM, H1975 IC50 = 0.095 µM), 17i (A549 IC50 = 4.17 µM, H1975 IC50 = 0.052 µM), 17j (A549 IC50 = 1.67 µM, H1975 IC50 = 0.061 µM) exhibited comparable antitumor activities and selectivity ratios compared to the positive control osimertinib (A549 IC50 = 2.91 µM, H1975 IC50 = 0.064 µM). In vitro inhibitory activities against EGFR kinases containing different mutations were also tested. Compound 17i showed remarkable inhibitory activity (with IC50 value of 1.7 nM) to EGFRL858R/T790M kinase and selectivity (22-folds compared to EGFRWT kinase). Furthermore, acridine orange/ethidium bromide (AO/EB) staining assay, cell apoptosis assay, cell cycle distribution assay and wound-healing assay of the compounds 9a and 17i were performed on H1975 cell line. The results showed dose-dependent activities of the induction of apoptosis, G0/G1-phase arrestation and inhibition of migration, which were similar to the positive control osimertinib. Additionally, molecular docking analysis was performed to seek the possible binding mode between the selected compounds (9a, 17i-17j) and EGFRL858R/T790M kinase. The results demonstrated that compound 17i is a promising candidate and worth further study.

9.
Mol Cell Probes ; 60: 101777, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34737039

RESUMO

Escherichia coli O157:H7 (E. coli O157:H7) is a common foodborne morbigenous microorganism, which can spread through fecal-oral transmission. Humans can be infected by ingesting foods and water contaminated with E. coli O157:H7, which can cause various symptoms. In present study, we have successfully developed a quick and hypersensitive fluorescent probe-based Recombinase-aided amplification (RAA) method and applied in E. coli O157:H7 detection at 39 °C in 20 min. The sensitivity of the assay in pure E. coli O157:H7 suspension was 5.6 × 100 CFU/mL. The fluorescent probe-based RAA assay was further applied in three samples, and the limit of detection (LOD) in skimmed milk, lettuces and lake water was 5.4 × 101 CFU/mL, 7.9 × 101 CFU/mL and 5.2 × 101 CFU/mL, separately. This method showed a high sensitivity and short detection time, which has the feasible application in on-site test in real samples.

10.
World J Gastrointest Oncol ; 13(9): 1099-1108, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34616515

RESUMO

Dysbiosis of the gastric microbiome is involved in the development of gastric cancer (GC). A number of studies have demonstrated an increase in the relative abundance of Lactobacillus in GC. In this review, we present data that support the overgrowth of Lactobacillus in GC from studies on molecular and bacterial culture of the gastric microbiome, discuss the heterogenic effects of Lactobacillus on the health of human stomach, and explore the potential roles of the overgrowth of Lactobacillus in gastric carcinogenesis. Further studies are required to examine the association between Lactobacillus and GC at strain and species levels, which would facilitate to elucidate its role in the carcinogenic process.

11.
Opt Express ; 29(16): 25365-25376, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34614869

RESUMO

A practical direct-view scheme for generating arbitrary high-order cylindrical vector (HCV) beams by cascading vortex half-wave plates (VHPs) is presented. The combination of odd number 2n-1 VHPs for n≥1 can realize (m2n-1-m2n-2+…+m1)-order CV beams, in which m is the order number of VHP and the corresponding subscript 2n-1 represents the arrangement number of VHPs, and the cascading of even number 2n ones can obtain (m2n-m2n-1+…+m2-m1)-order CV beams. All 1-12 order CV beams, including the high-order anti-vortex CV (ACV) beams, are generated only by selectively cascading the VHPs with m=1, 3 and 8. The polarization properties of the generated HCV beams are investigated by measuring the corresponding Stokes parameters. It is experimentally demonstrated that arbitrary HCV beams are effectively achieved by the proposed method. The order numbers of CV beams can be greatly expanded by cascading limited types of VHPs.

12.
Exp Ther Med ; 22(6): 1389, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34650637

RESUMO

Increasing evidence suggest that NOD-like receptor protein 3 (NLRP3) inflammasome-mediated pyroptosis may be the underlying pathological mechanism of sepsis-induced cardiomyopathy. DDX3X, an ATP-dependent RNA helicase, plays a vital role in the formation of the NLRP3 inflammasome by directly interacting with cytoplasmic NLRP3. However, whether DDX3X has a direct impact on lipopolysaccharide (LPS)-induced cardiomyocyte injury by regulating NLRP3 inflammasome assembly remains unclear. The present study aimed to investigate the role of DDX3X in the activation of the NLRP3 inflammasome and determine the molecular mechanism of DDX3X action in LPS-induced pyroptosis in H9c2 cardiomyocytes. H9c2 cardiomyocytes were treated with LPS to simulate sepsis in vitro. The results demonstrated that LPS stimulation upregulated DDX3X expression in H9c2 cardiomyocytes. Furthermore, Ddx3x knockdown significantly attenuated pyroptosis and cell injury in LPS-treated H9c2 cells by suppressing NLRP3 inflammasome activation. Taken together, these results suggest that DDX3X is involved in LPS-induced cardiomyocyte pyroptosis, and DDX3X deficiency mitigates cardiomyocyte damage induced by LPS treatment.

13.
Sci Rep ; 11(1): 20931, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34686713

RESUMO

The activities of various MgO catalysts, which were prepared from different methods such as hydration synthesis, thermal decomposition, combustion, sol-gel and co-precipitation, were conducted in dimethyl carbonate (DMC) synthesis via transesterification of ethylene carbonate with methanol. MgO-P-Na2CO3-3.14 synthesized by the excess Na2CO3 precipitation compared the best catalytic activity and stability, which could be reused for seven times without obvious deactivation. The DMC yield was as high as 69.97% at 68 °C. The transesterification reaction could be separated into two steps, and the samples obtained by NaOH precipitant exhibited better ring-opening capability, while the catalysts acquired by Na2CO3 precipitant displayed superior transesterification ability. The structure-performance relationship was evaluated by multiple characterization methods. The results indicated that the as-synthesized catalyst derived from dried precursors with more crystalline magnesium carbonate was favorable for the promotion of DMC yield, and MgO-P-Na2CO3-3.14 with more Mg-O pairs, which were the active center for the transesterification of 2-hydroxyethyl methyl carbonate (HEMC) intermediate with methanol, resulted in more moderately basic sites left that was in accordance with the DMC yield variation. MgO-P-Na2CO3-3.14 with greater BET surface area and mesopore volume, relative low surface oxygen content and larger moderately basic sites amount compared the excellent activity in DMC synthesis.

14.
J Phys Chem Lett ; 12(40): 9926-9932, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34613726

RESUMO

The GPU-accelerated molecular dynamics simulations are performed to explore the dynamical inserting process of ionic liquids (ILs) into the lipid bilayer. We found that the free ions and clusters coexist in the system, but only the cation can insert into the lipid bilayer. In specific, after a microsecond-scale simulation (up to 1.16 µs), the inserting rate increases first and then decreases nonmonotonic as side chain of cation (nchain) elongates, peaking at nchain = 10. However, the inserting free energy decreases with nchain, indicating the inserting process is easier for the larger nchain. Such contrary originates from the formation of cluster, where the cluster dissociating energy shows that only cluster for nchain ≤ 10 can dissociate spontaneously. Hence, the inserting rate is determined by the balance between nchain and cluster stability. These quantitative competition mechanisms shed light to the rational design of the biocompatible ILs toward their applications in the biochemical-related fields.

15.
Ecotoxicol Environ Saf ; 225: 112749, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34488142

RESUMO

The effects of long-term rare earth element (REE) and heavy metal (HM) contamination on soil bacterial communities remains poorly understood. In this study, soil samples co-contaminated with REEs and HMs were collected from a rare-earth tailing dam. The bacterial community composition and diversity were analyzed through Illumina high-throughput sequencing with 16S rRNA gene amplicons. Bacterial community richness and diversity were lower in the co-contaminated soils than in the uncontaminated soils, with clearly different bacterial community compositions. The results showed that total organic carbon and available potassium were the most important factors affecting bacterial community richness and diversity, followed by the REE and HM contents. Although the canonical correspondence analysis results showed that an REE alone had no obvious effects on bacterial community structures, we found that the combined effects of soil physicochemical properties and REE and HM contents regulated bacterial community structure and composition. The effects of REEs and HMs on bacterial communities were similar, whereas their combined contributions were greater than the individual effects of REEs or HMs. Some bacterial taxa were worth noting. These specifically included the plant growth-promoting bacteria Exiguobacterium (sensitive to REEs and HMs) and oligotrophic microorganisms with metal tolerance (prevalent in contaminated soil); moreover, relative abundance of JTB255-Marine Benthic Group, Rhodobacteraceae, Erythrobacter, and Truepera may be correlated with REEs. This study was the first to investigate the responses of bacterial communities to REE and HM co-contamination. The current results have major implications for the ecological risk assessment of environments co-contaminated with REEs and HMs.


Assuntos
Metais Pesados , Poluentes do Solo , Bactérias/genética , Metais Pesados/análise , Metais Pesados/toxicidade , RNA Ribossômico 16S/genética , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
16.
BMC Cancer ; 21(1): 1027, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34525964

RESUMO

BACKGROUND: Previous research found that the cancer history of an individual's sibling may be a better indicator than that of the parents. We aim to provide recommendations for opportunistic screening for individuals whose sibling had been diagnosed with cancer. METHODS: During the physical examination in Cancer Hospital, Chinese Academy of Medical Sciences, 43,300 people were asked if they have at least two siblings who developed cancer. RESULTS: A total of 1270 sibling-pairs from 766 families developed cancer, including 367 pairs of brothers (Bro-pairs), 368 pairs of sisters (Sis-pairs), and 535 pairs of brother-and-sister (BroSis-pairs). The mean ages at diagnosis of cancer for the three groups were from 58 to 62 years. More than half of Bro-pairs (55.3%) or Sis-pairs (51.1%) had cancer from the same systemic origin, and more than a quarter of Bro-pairs (28.1%) and Sis-pairs (37.2%) developed the same type of cancer. However, only 36.0% of BroSis-pairs developed cancers from the same systemic origin, and 18.9% developed the same type of cancer. In Bro-pairs and BroSis-pairs, lung cancer and digestive system cancer were the most common cancers, while in Sis-pairs, breast cancer, lung cancer, cervical cancer, liver cancer and thyroid cancer were the most common ones. CONCLUSIONS: If an individual's sibling is diagnosed with cancer, the individual should consider participating in opportunistic screening annually, especially for lung cancer and digestive system cancers for both sexes. For sisters, breast cancer, cervical cancer and thyroid cancer should be screened early. Additionally, genetic services are essential for individuals who have siblings with cancer.


Assuntos
Neoplasias/diagnóstico , Irmãos , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , China/epidemiologia , Neoplasias do Sistema Digestório/diagnóstico , Neoplasias do Sistema Digestório/epidemiologia , Detecção Precoce de Câncer , Neoplasias das Glândulas Endócrinas/diagnóstico , Neoplasias das Glândulas Endócrinas/epidemiologia , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Distribuição por Sexo , Fatores Sexuais , Neoplasias Urogenitais/diagnóstico , Neoplasias Urogenitais/epidemiologia
17.
J Dairy Sci ; 104(12): 12342-12352, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34482981

RESUMO

Rapid and credible detection of pathogens is essential to prevent and control outbreaks of foodborne diseases. In this study, a poly-l-lysine-functionalized magnetic beads (PLL-MB) strategy combined with a PCR assay was established to detect Staphylococcus aureus. We also detected Escherichia coli O157:H7 to further verify the strategy for gram-negative bacteria detection. Poly-l-lysine has strong positive charges because of its amino groups, which can conjugate with the carboxyl of carboxyl magnetic beads. Furthermore, it can be used to combine with bacteria through electrostatic adsorption. Under optimum conditions, the developed PLL-MB complexes showed 90% capture efficiency in phosphate-buffered saline and 85% capture efficiency in milk for S. aureus detection. The limit of detection of the PLL-MB-PCR assay was 102 cfu/mL (1.8 × 102 cfu/mL for S. aureus and 7 × 102 cfu/mL for E. coli O157:H7) in phosphate-buffered saline and milk samples. The whole assay can be performed within 4 h. The proposed strategy showed a lower limit of detection when compared with the conventional PCR assay without enrichment. In addition, this method exhibited the advantages of a high-efficient, cost-efficient, and simple operation, indicating its potential applications in foodborne pathogen detection.


Assuntos
Escherichia coli O157 , Animais , Escherichia coli O157/genética , Microbiologia de Alimentos , Fenômenos Magnéticos , Leite , Polilisina , Reação em Cadeia da Polimerase/veterinária , Staphylococcus aureus
18.
J Dairy Sci ; 104(12): 12365-12374, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34531051

RESUMO

Cronobacter sakazakii is a foodborne, emerging opportunistic pathogen that causes severe bacteremia, necrotizing enterocolitis, and sepsis with a mortality rate of up to 80%. In this study, we developed a simple and sensitive fluorescent turn-off aptasensor with rolling circle amplification assay for viable C. sakazakii detection in powdered infant formula. The results showed that the proposed aptasensor has good performance and specificity for detecting viable C. sakazakii in pure culture and powdered infant formula samples within 3 h. Under the optimal reaction conditions, there is a linear relationship between fluorescent intensity at 490 nm and logarithmic concentration of C. sakazakii in the range of 2.7 × 105 to 2.7 × 102 cfu/mL, with a limit of detection of 2.7 × 102 cfu/mL in pure culture. The proposed aptasensor achieved a recovery of 104 to 111% in pure culture, and 96 to 107% in spiked powdered infant formula samples. The proposed aptasensor does not require complicated DNA extraction steps or antibodies, and can be performed at 37°C, making it a convenient and sensitive strategy for C. sakazakii detection.


Assuntos
Cronobacter sakazakii , Cronobacter , Animais , Cronobacter/genética , Microbiologia de Alimentos , Fórmulas Infantis/análise , Pós
19.
Microvasc Res ; 139: 104240, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34508787

RESUMO

Aging contributes to the progression of vascular dysfunction and is a major nonreversible risk factor for cardiovascular disease. The aim of this study was to determine the effectiveness of using arterial pulse-wave measurements, frequency-domain pulse analysis, and machine-learning analysis in distinguishing vascular aging. Radial pulse signals were measured noninvasively for 3 min in 280 subjects aged 40-80 years. The cardio-ankle vascular index (CAVI) was used to evaluate the arterial stiffness of the subjects. Forty frequency-domain pulse indices were used as features, comprising amplitude proportion (Cn), coefficient of variation of Cn, phase angle (Pn), and standard deviation of Pn (n = 1-10). Multilayer perceptron and random forest with supervised learning were used to classify the data. The detected differences were more prominent in the subjects aged 40-50 years. Several indices differed significantly between the non-vascular-aging group (aged 40-50 years; CAVI <9) and the vascular-aging group (aged 70-80 years). Fivefold cross-validation revealed an excellent ability to discriminate the two groups (the accuracy was >80%, and the AUC was >0.8). For subjects aged 50-60 and 60-70 years, the detection accuracies of the two trained algorithms were around 80%, with AUCs of >0.73 for both, which indicated acceptable discrimination. The present method of frequency-domain analysis may improve the index reliability for further machine-learning analyses of the pulse waveform. The present noninvasive and objective methodology may be meaningful for developing a wearable-device system to reduce the threat of vascular dysfunction induced by vascular aging.

20.
Antimicrob Agents Chemother ; 65(11): e0106321, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-34491805

RESUMO

SCTA01 is a novel monoclonal antibody with promising prophylactic and therapeutic potential for COVID-19. This study aimed to evaluate the safety, tolerability, pharmacokinetics (PK) and immunogenicity of SCTA01 in healthy adults. This was a randomized, double-blind, placebo-controlled, dose escalation phase I clinical trial. Healthy adults were randomly assigned to cohort 1 (n = 5; 3:2), cohort 2 (n = 8; 6:2), cohort 3, or cohort 4 (both n = 10; 8:2) to receive SCTA01 (5, 15, 30, and 50 mg/kg, respectively) versus placebo. All participants were followed up for clinical, laboratory, PK, and immunogenicity assessments for 84 days. The primary outcomes were the dose-limiting toxicity (DLT) and maximal tolerable dose (MTD), and the secondary outcomes included PK parameters, immunogenicity, and adverse events (AE). Of the 33 participants, 18 experienced treatment-related AEs; the frequency was 52.0% (13/25) in participants receiving SCTA01 and 62.5% (5/8) in those receiving placebo. All AEs were mild. There was no serious AE or death. No DLT was reported, and the MTD of SCTA01 was not reached. SCTA01 with a dose range of 5 to 50 mg/kg had nearly linear dose-proportional increases in Cmax and AUC parameters. An antidrug antibody response was detected in four (16.0%) participants receiving SCTA01, with low titers, between the baseline and day 28, but all became negative later. In conclusion, SCTA01 up to 50 mg/kg was safe and well-tolerated in healthy participants. Its PK parameters were nearly linear dose-proportional. (This study has been registered at ClinicalTrials.gov under identifier NCT04483375.).


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Anticorpos Monoclonais/efeitos adversos , Anticorpos Antivirais , Método Duplo-Cego , Humanos
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