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1.
Small ; : e2405618, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39264000

RESUMO

Since the coronavirus pandemic, mRNA vaccines have revolutionized the field of vaccinology. Lipid nanoparticles (LNPs) are proposed to enhance mRNA delivery efficiency; however, their design is suboptimal. Here, a rational method for designing LNPs is explored, focusing on the ionizable lipid composition and structural optimization using machine learning (ML) techniques. A total of 213 LNPs are analyzed using random forest regression models trained with 314 features to predict the mRNA expression efficiency. The models, which predict mRNA expression levels post-administration of intradermal injection in mice, identify phenol as the dominant substructure affecting mRNA encapsulation and expression. The specific phospholipids used as components of the LNPs, as well as the N/P ratio and mass ratio, are found to affect the efficacy of mRNA delivery. Structural analysis highlights the impact of the carbon chain length on the encapsulation efficiency and LNP stability. This integrated approach offers a framework for designing advanced LNPs and has the potential to unlock the full potential of mRNA therapeutics.

2.
J Infect Dis ; 225(5): 777-784, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-34850034

RESUMO

BACKGROUND: There are limited data directly comparing immune responses to vaccines and to natural infections with coronavirus disease 2019 (COVID-19). This study assessed the immunogenicity of the BNT162b2 and ChAdOx1 nCoV-19 vaccines over a 3-month period and compared the immune responses with those to natural infections. METHOD: We enrolled healthcare workers who received BNT162b2 or ChAdOx1 nCoV-19 vaccines and patients with confirmed COVID-19 and then measured S1 immunoglobulin (Ig) G and neutralizing antibodies and T-cell responses. RESULTS: A total of 121 vaccinees and 26 patients with confirmed COVID-19 were analyzed. After the second dose, the BNT162b2 vaccine yielded S1 IgG antibody responses similar to those achieved with natural infections (mean IgG titer [standard deviation], 2241 [899] vs 2601 [5039]; P = .68) but significantly stronger than responses to the ChAdOx1 vaccine (174 [96]; P < .001). The neutralizing antibody titer generated by BNT162b2 was 6-fold higher than that generated by ChAdOx1 but lower than that by natural infection. T-cell responses persisted for 3 months with BNT162b2 and natural infection but decreased with ChAdOx1. CONCLUSIONS: Antibody responses after the second dose of BNT162b2 are higher than after the second dose of ChAdOx1 and like those occurring after natural infection. T-cell responses are maintained longer in BNT162b2 vaccinees than in ChAdOx1 vaccinees.


Assuntos
Vacina BNT162/imunologia , COVID-19/prevenção & controle , ChAdOx1 nCoV-19/imunologia , SARS-CoV-2/imunologia , Adulto , Idoso , Anticorpos Neutralizantes/imunologia , Formação de Anticorpos/imunologia , Vacina BNT162/administração & dosagem , Vacina BNT162/efeitos adversos , COVID-19/epidemiologia , COVID-19/imunologia , ChAdOx1 nCoV-19/administração & dosagem , ChAdOx1 nCoV-19/efeitos adversos , Feminino , Humanos , Imunoglobulina G , Masculino , Pessoa de Meia-Idade , Vacinação
3.
Molecules ; 27(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36296616

RESUMO

Although C17 polyacetylenes from Panax ginseng exhibit cytotoxic properties against various tumor cells, there have been few experiments on epithelial ovarian carcinoma cells. This study aimed to investigate the cytotoxic effects of C17 polyacetylenes from P. ginseng against ovarian cancer cell lines. Four unreported (1-4) and fifteen known (5-19) C17 polyacetylenes were obtained from the roots of P. ginseng using repeated chromatography (open column, MPLC, and preparative HPLC). The chemical structures of all the compounds were determined by analyzing their spectroscopic data (NMR, IR, and optical rotation) and HR-MS. The structures of new polyacetylenes were elucidated as (3S,8S,9R,10R)-(-)-heptadeca-9,10-epoxy-4,6-diyne-3,8-diyl diacetate (1), (3S,8S,9R,10R)-(-)-heptadeca-1-en-9,10-epoxy-4,6-diyne-3,8-diyl diacetate (2), (-)-haptadeca-9,10-epoxy-8-methoxy-4,6-diyne-3,11-diol (3), and (3R,9R,10R)-(+)-3-acetoxy-9,10-dihydroxyheptadeca-1-en-4,6-diyne (4), named ginsenoynes O, P, and Q, and 3-acetyl panaxytriol, respectively. Subsequently, in vitro experiments on A2780 and SKOV3 human epithelial ovarian carcinoma cells were performed to assess the cytotoxic properties of the isolates. Among the isolates, panaquinquecol 4 (15) exhibited the most remarkable cytotoxic effects on both human ovarian cancer cells A2780 (IC50 value of 7.60 µM) and SKOV3 (IC50 value of 27.53 µM). Therefore, C17 polyacetylenes derived from P. ginseng may warrant further investigation for their therapeutic potential in epithelial ovarian cancer.


Assuntos
Neoplasias Ovarianas , Panax , Humanos , Feminino , Panax/química , Carcinoma Epitelial do Ovário , Polímero Poliacetilênico , Linhagem Celular Tumoral , Neoplasias Ovarianas/tratamento farmacológico , Poli-Inos/farmacologia , Poli-Inos/química , Raízes de Plantas/química
4.
Molecules ; 27(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36500714

RESUMO

To test whether homologous recombination repair (HRR) depends on FOXO3a, a cellular aging model of human dermal fibroblast (HDF) and tet-on flag-h-FOXO3a transgenic mice were studied. HDF cells transfected with over-expression of wt-h-FOXO3a increased the protein levels of MRE11, BRCA1, BRIP1, and RAD50, while knock-down with siFOXO3a decreased them. The protein levels of MRE11, BRCA1, BRIP1, RAD50, and RAD51 decreased during cellular aging. Chromatin immunoprecipitation (ChIP) assay was performed on FOXO3a binding accessibility to FOXO consensus sites in human MRE11, BRCA1, BRIP1, and RAD50 promoters; the results showed FOXO3a binding decreased during cellular aging. When the tet-on flag-h-FOXO3a mice were administered doxycycline orally, the protein and mRNA levels of flag-h-FOXO3a, MRE11, BRCA1, BRIP1, and RAD50 increased in a doxycycline-dose-dependent manner. In vitro HRR assays were performed by transfection with an HR vector and I-SceI vector. The mRNA levels of the recombined GFP increased after doxycycline treatment in MEF but not in wt-MEF, and increased in young HDF comparing to old HDF, indicating that FOXO3a activates HRR. Overall, these results demonstrate that MRE11, BRCA1, BRIP1, and RAD50 are transcriptional target genes for FOXO3a, and HRR activity is increased via transcriptional activation of MRE11, BRCA1, BRIP1, and RAD50 by FOXO3a.


Assuntos
Reparo do DNA , Reparo de DNA por Recombinação , Humanos , Camundongos , Animais , Ativação Transcricional , DNA Helicases/genética , RNA Mensageiro , Proteínas de Ligação a DNA/genética , Hidrolases Anidrido Ácido/genética , Proteína BRCA1/genética
5.
Medicina (Kaunas) ; 57(1)2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33467547

RESUMO

Pathology of the lumbar spine and hip joint can commonly coexist in the elderly. Anterior and lateral leg pain as symptoms of hip osteoarthritis and spinal stenosis can closely resemble each other, with only subtle differences in both history and physical examinations. It is not easy to identify the origin of this kind of hip pain. The possibility of hip osteoarthritis should not be underestimated, as this could lead to an incorrect diagnosis and inappropriate spinal surgery. We report the case of a 54-year-old female with chronic right anterior and lateral leg pain who did not respond to repeated spinal blocks based on lumbar MRI, but in whom hip osteoarthritis was considered since severe atrophy of the ipsilateral psoas muscle was identified. We suggest that severe psoas muscle atrophy can be a clinical clue to identify hip osteoarthritis and is related to lower extremity pain, even if there is a coexisting lumbar spine pathology.


Assuntos
Osteoartrite do Quadril , Estenose Espinal , Idoso , Atrofia , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Pessoa de Meia-Idade , Osteoartrite do Quadril/complicações , Osteoartrite do Quadril/diagnóstico por imagem , Músculos Psoas/diagnóstico por imagem , Músculos Psoas/patologia , Estenose Espinal/complicações , Estenose Espinal/diagnóstico por imagem , Estenose Espinal/cirurgia
6.
Molecules ; 25(8)2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32340370

RESUMO

Kinetoplastid parasites, including Leishmania and Trypanosoma spp., are life threatening pathogens with a worldwide distribution. Next-generation therapeutics for treatment are needed as current treatments have limitations, such as toxicity and drug resistance. In this study, we examined the activities of established mammalian target of rapamycin (mTOR)/phosphoinositide 3-kinase (PI3K) inhibitors against these tropical diseases. High-throughput screening of a library of 1742 bioactive compounds against intracellular L. donovani was performed, and seven mTOR/PI3K inhibitors were identified. Dose-dilution assays revealed that these inhibitors had half maximal effective concentration (EC50) values ranging from 0.14 to 13.44 µM for L. donovani amastigotes and from 0.00005 to 8.16 µM for T. brucei. The results of a visceral leishmaniasis mouse model indicated that treatment with Torin2, dactolisib, or NVP-BGT226 resulted in reductions of 35%, 53%, and 54%, respectively, in the numbers of liver parasites. In an acute T. brucei mouse model using NVP-BGT226 parasite numbers were reduced to under the limits of detection by five consecutive days of treatment. Multiple sequence and structural alignment results indicated high similarities between mTOR and kinetoplastid TORs; the inhibitors are predicted to bind in a similar manner. Taken together, these results indicated that the TOR pathways of parasites have potential for the discovery of novel targets and new potent inhibitors.


Assuntos
Antiprotozoários/farmacologia , Leishmania donovani/efeitos dos fármacos , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Trypanosoma brucei brucei/efeitos dos fármacos , Animais , Antiprotozoários/química , Sítios de Ligação , Linhagem Celular , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Camundongos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Inibidores de Fosfoinositídeo-3 Quinase/química , Ligação Proteica , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/química
7.
Mar Drugs ; 17(6)2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31234277

RESUMO

Cardiac progenitor cells (CPCs) are resident stem cells present in a small portion of ischemic hearts and function in repairing the damaged heart tissue. Intense oxidative stress impairs cell metabolism thereby decreasing cell viability. Protecting CPCs from undergoing cellular apoptosis during oxidative stress is crucial in optimizing CPC-based therapy. Histochrome (sodium salt of echinochrome A-a common sea urchin pigment) is an antioxidant drug that has been clinically used as a pharmacologic agent for ischemia/reperfusion injury in Russia. However, the mechanistic effect of histochrome on CPCs has never been reported. We investigated the protective effect of histochrome pretreatment on human CPCs (hCPCs) against hydrogen peroxide (H2O2)-induced oxidative stress. Annexin V/7-aminoactinomycin D (7-AAD) assay revealed that histochrome-treated CPCs showed significant protective effects against H2O2-induced cell death. The anti-apoptotic proteins B-cell lymphoma 2 (Bcl-2) and Bcl-xL were significantly upregulated, whereas the pro-apoptotic proteins BCL2-associated X (Bax), H2O2-induced cleaved caspase-3, and the DNA damage marker, phosphorylated histone (γH2A.X) foci, were significantly downregulated upon histochrome treatment of hCPCs in vitro. Further, prolonged incubation with histochrome alleviated the replicative cellular senescence of hCPCs. In conclusion, we report the protective effect of histochrome against oxidative stress and present the use of a potent and bio-safe cell priming agent as a potential therapeutic strategy in patient-derived hCPCs to treat heart disease.


Assuntos
Miócitos Cardíacos/efeitos dos fármacos , Naftoquinonas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Anexina A5/metabolismo , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Senescência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/farmacologia , Miócitos Cardíacos/metabolismo , Traumatismo por Reperfusão/induzido quimicamente , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Federação Russa , Proteína X Associada a bcl-2/metabolismo
8.
J Phys Ther Sci ; 30(4): 540-543, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29706702

RESUMO

[Purpose] The purpose of this study was to examine the correlation between the quadriceps angle and muscle-activation ratios for the vastus medialis, rectus femoris, and vastus lateralis during various activities. [Subjects and Methods] Seventeen heathy females were recruited. The quadriceps angles were measured with long-arm goniometers. The muscle activity of the vastus medialis, rectus femoris, and vastus lateralis were measured using electromyography under four different activity settings: walking, squatting, step-up, and sit-to-stand. The muscle activation ratios were calculated and their correlations with the quadriceps angles were analyzed. [Results] The activation ratio of the rectus femoris to the vastus medialis (and, although less significant, of the vastus lateralis to the vastus medialis) was positively correlated with the quadriceps angle during the step-up and sit-to-stand. A similar tendency was also seen during squatting. The activation ratio of the vastus lateralis to the rectus femoris was negatively correlated with the quadriceps angle during walking. [Conclusion] The relative muscle activity among the muscles composing the quadriceps was correlated with the quadriceps angle. During activities involving deeper knee flexion like the step-up, sit-to-stand, and squatting, the relative activity of the lateral muscles tended to increase as the quadriceps angle increased. Meanwhile, during walking the activity of the medial muscles seemed to increase with a larger quadriceps angle.

9.
PLoS One ; 18(9): e0288432, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37768896

RESUMO

Image search systems could be endangered by adversarial attacks and data perturbations. The image retrieval system can be compromised either by distorting the query or hacking the ranking system. However, existing literature primarily discusses attack methods, whereas the research on countermeasures to defend against such adversarial attacks is rare. As a defense mechanism against the intrusions, quality assessment can complement existing image retrieval systems. "GuaRD" is proposed as an end-to-end framework that uses the quality metric as a weighted-regularization term. Proper utilization and balance of the two features could lead to reliable and robust ranking; the original image is assigned a higher rank while the distorted image is assigned a relatively lower rank. Meanwhile, the primary goal of the image retrieval system is to prioritize searching the relevant images. Therefore, the use of leveraged features should not compromise the accuracy of the system. To evaluate the generality of the framework, we conducted three experiments on two image quality assessment(IQA) benchmarks (Waterloo and PieAPP). For the first two tests, GuaRD achieved enhanced performance than the existing model: the mean reciprocal rank(mRR) value of the original image predictions increased by 61%, and the predictions for the distorted input query decreased by 18%. The third experiment was conducted to analyze the mean average precision (mAP) score of the system to verify the accuracy of the retrieval system. The results indicated little deviation in performance between the tested methods, and the score was not effected or slightly decreased by 0.9% after the GuaRD was applied. Therefore, GuaRD is a novel and robust framework that can act as a defense mechanism for data distortions.


Assuntos
Benchmarking , Motivação , Projetos de Pesquisa
10.
Arch Med Res ; 54(2): 86-94, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36702668

RESUMO

BACKGROUD AND AIM: Endometriosis is one of the most common gynecological diseases associated with chronic pelvic pain, infertility, and cancer. However, its molecular pathogenesis remains unclear. This study aimed to identify key genes involved in the pathogenesis of endometriosis. METHODS: Bioinformatic analyses were perfomed to identify key differentially expressed genes (DEGs), transcription factors (TFs), and functionally enriched pathways. Effect of SPI1 on migration, invasion, expression of ADH1B, MYH11, and PLN were analyzed in human endometriotic cells. RESULTS: By screening three transcriptome datasets from the GEO for overlapping DEGs between eutopic and ectopic endometria in patients with endometriosis, we found that the expression of ADH1B, MYH11, and PLN was markedly upregulated in the ectopic endometrium. Knockdown of ADH1B, MYH11, and PLN significantly inhibited the migration and invasion of human endometriotic 12Z cells. Additionally, gene set enrichment analysis revealed that epithelial-mesenchymal transition gene signature was positively correlated with ADH1B, MYH11, and PLN expression. Notably, the TF SPI1 was found to regulate the expression of these three genes in the endometriotic tissues and 12TZ cells. Moreover, SPI1 expression was associated with the invasion of endometriotic cells and was increased in the ectopic endometrium of patients with endometriosis. CONCLUSION: These data suggest that SPI1 plays a key role in the progression of endometriosis by regulating ADH1B, MYH11, and PLN expression and may therefore serve as a potential prognostic and therapeutic factor for endometriosis.


Assuntos
Endometriose , Feminino , Humanos , Endometriose/metabolismo , Regulação para Cima , Transição Epitelial-Mesenquimal , Fenótipo , Endométrio/metabolismo , Endométrio/patologia
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