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1.
Sensors (Basel) ; 23(15)2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37571755

RESUMO

Sound classification has been widely used in many fields. Unlike traditional signal-processing methods, using deep learning technology for sound classification is one of the most feasible and effective methods. However, limited by the quality of the training dataset, such as cost and resource constraints, data imbalance, and data annotation issues, the classification performance is affected. Therefore, we propose a sound classification mechanism based on convolutional neural networks and use the sound feature extraction method of Mel-Frequency Cepstral Coefficients (MFCCs) to convert sound signals into spectrograms. Spectrograms are suitable as input for CNN models. To provide the function of data augmentation, we can increase the number of spectrograms by setting the number of triangular bandpass filters. The experimental results show that there are 50 semantic categories in the ESC-50 dataset, the types are complex, and the amount of data is insufficient, resulting in a classification accuracy of only 63%. When using the proposed data augmentation method (K = 5), the accuracy is effectively increased to 97%. Furthermore, in the UrbanSound8K dataset, the amount of data is sufficient, so the classification accuracy can reach 90%, and the classification accuracy can be slightly increased to 92% via data augmentation. However, when only 50% of the training dataset is used, along with data augmentation, the establishment of the training model can be accelerated, and the classification accuracy can reach 91%.

2.
J Pharm Biomed Anal ; 233: 115420, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37207489

RESUMO

Quantitation of host cell proteins (HCPs) is essential in the process of preparation of many biological and vaccine products. Common methods of quantitation include the widely applied enzyme-linked immunosorbent assays (ELISAs), mass spectrometry (MS) and other orthogonal assays. Prior to using these techniques, critical reagents need to be evaluated, for example, antibodies need to be assessed for HCP coverage. Percent of HCP coverage is often established by denatured 2D Western blot. However, ELISAs measure the amount of HCP only in a native state. There are limited studies linking reagents validated by 2D-Western to ensure adequate coverage in the final ELISA. ProteinSimple's newly developed capillary Western blot technology allows for separation, blotting, and detection of proteins in a semi-automated and simplified format. Capillary Westerns are similar to slab Westerns, with the added benefit of being quantitative. Here we outline the capillary Western method that links the 2D Western coverage and ultimately ELISAs for more efficient HCP quantitation. This study describes the development of the capillary Western analytical method to quantitively evaluate HCPs in Vero and Chinese Hamster Ovarian (CHO) cell lines. The amount of CHO HCPs decreases as the sample is purified as expected. Using this approach, we determined that the detected Vero HCPs amount was similar irrespective of denatured (capillary Western) versus native assay format (ELISA). This new method can also be potentially employed to quantitatively assess the anti-HCP antibody reagent coverage used in commercial HCP ELISA kits.


Assuntos
Produtos Biológicos , Proteínas , Cricetinae , Animais , Cricetulus , Proteínas/análise , Células CHO , Western Blotting
3.
Biotechnol Bioeng ; 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37209394

RESUMO

Live virus vaccine (LVV) purification, employing chromatography, can be challenged by low binding capacities and elution yields. Alternatively, processes relying solely on enzymatic digestion steps and size-based membrane separations can be limited by suboptimal reduction of process related impurities and poorly scalable unit operations. Here, we demonstrate that the combination of flowthrough mode chromatography and an ultrafiltration/diafiltration (UF/DF) unit operation delivers a purification process for two different LVV candidates, V590 and Measles, expressed in adherent Vero cells. For V590, chromatography with mixed mode cation exchange resins returned final product yields of ∼50% and logarithmic reduction values (LRVs) of 1.7->3.4 and 2.5-3.0 for host cell DNA (hcDNA) and host cell proteins (HCPs), respectively. For Measles, chromatography with mixed mode anion exchange resins returned final product yields of ∼50% and LRVs of 1.6 and 2.2 for hcDNA and HCPs, respectively. For both V590 and Measles processing, the employed resins cleared a key HCP, fibronectin, which could foul the UF/DF unit operation, and thusly enabling it to further reduce HCPs and to formulate the final LVV products. This integrated purification process utilizes the complementary action of the two unit operations and its applicability across LVVs supports its consideration for their processing.

4.
Emerg Infect Dis ; 28(3): 599-607, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35195517

RESUMO

Vancomycin-resistant Clostridium innocuum was recently identified as an etiologic agent for antibiotic-associated diarrhea in humans. We conducted a case-control study involving 152 C. innocuum-infected patients during 2014-2019 in Taiwan, using 304 cases of Clostridioides difficile infection (CDI) matched by diagnosis year, age (+2 years), and sex as controls. The baseline characteristics were similar between the 2 groups. C. innocuum-infected patients experienced more extraintestinal clostridial infection and gastrointestinal tract-related complications than did patients with CDI. The 30-day mortality rate among C. innocuum-infected patients was 14.5%, and the overall rate was 23.0%. Chronic kidney disease, solid tumor, intensive care unit admission, and shock status were 4 independent risk factors for death. C. innocuum identified from clinical specimens should be recognized as a pathogen requiring treatment, and because of its intrinsic vancomycin resistance, precise identification is necessary to guide appropriate and timely antimicrobial therapy.


Assuntos
Infecções por Clostridium , Firmicutes , Antibacterianos/uso terapêutico , Estudos de Casos e Controles , Pré-Escolar , Infecções por Clostridium/tratamento farmacológico , Infecções por Clostridium/epidemiologia , Humanos , Taiwan/epidemiologia
5.
Anticancer Res ; 40(8): 4491-4504, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32727779

RESUMO

BACKGROUND: Peroxiredoxin II (PRDX2) performs unique roles in cells. It can reduce peroxides through cysteine residues, and helps prevent the effects of oxidative stress on cells. It is closely related to the occurrence and development of various diseases, especially alcoholic liver injury and even liver cancer. The metabolism of alcohol in hepatocytes leads to the increase in the levels of reactive oxygen species (ROS), oxidative stress, injury, and apoptosis. Therefore, this study focused on the investigating the protection conferred by PRDX2 against alcohol-induced apoptosis of hepatocytes. MATERIALS AND METHODS: PRDX2 inhibition of alcohol-induced apoptosis in L02 hepatocytes was analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, fluorescence microscopy, flow cytometry, western blotting and hematoxylin and eosin staining. RESULTS: The results showed that the levels of reactive oxygen species, protein kinase B, ß-catenin, B-cell lymphoma-2 (BCL2), BCL-XL, BCL2-associated X, cleaved caspase-3, and cleaved poly (ADP-ribose) polymerase in PRDX2-silenced cells were increased significantly after the treatment of cells with ethanol. Similar results were obtained in an in vivo Prdx2-knockout mouse model of alcoholic liver injury. Therefore, PRDX2 may regulate the phosphorylation of the AKT signal protein by eliminating reactive oxygen species from cells, and it inhibits the downstream mitochondria-dependent apoptosis pathway, and, thereby, the apoptosis of cells. CONCLUSION: Thus, PRDX2 may be a potential molecular target for the prevention and treatment of alcoholic liver injury.


Assuntos
Etanol/efeitos adversos , Hepatócitos/citologia , Peroxirredoxinas/genética , Transdução de Sinais , Apoptose , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Fosforilação/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , beta Catenina/metabolismo
6.
Open Heart ; 5(2): e000891, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30487981

RESUMO

Background: Although remote ischaemic preconditioning (RIP) provides protection against myocardial ischaemia and reperfusion injury during cardiac surgery, it is not widely used. Systemic intermittent hypoxic-hyperoxic training (IHHT) may be a suitable alternative. Methods: This is a prospective, single-centre, randomised controlled trial. 127 patients with ischaemic heart disease and indication for coronary artery bypass graft (CABG) surgery from the Cardiology Clinic IM Sechenov First Moscow State Medical University were randomly assigned to IHHT, IHHT-control or RIP. Primary endpoint was serum concentration of troponin I and lactate 2 and 24 hours after surgery. Results: Median value for troponin I 24 hours after surgery was 1.068 (0.388-1.397) ng/mL in the IHHT group and was significantly lower compared with IHHT-controls with 1.980 (1.068-3.239) ng/mL (p=0.012) and to the RIP group with 1.762 (1.288-2.186) ng/mL (p=0.029), while there was no significant difference between RIP and the IHHT-control. Serum lactate after surgery was 1.74 (1.23-2.04) mmol/L in the IHHT group and was also significantly lower compared with IHHT-controls with 2.10 (1.80-2.29) mmol/L (p=0.045) and RIP with 2.12 (1.91-2.33) mmol/L (p=0.032). No significant complications or serious adverse events were observed during IHHT. Intraoperative and early postoperative complications did not differ significantly between groups. Conclusions: The results of this first trial using IHHT for myocardial protection against perioperative ischaemic myocardial injury in patients undergoing CABG surgery are promising and further larger trials should be done with adequate power to detect clinical rather than surrogate marker benefits.

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