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1.
Biochem Biophys Res Commun ; 696: 149469, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38194806

RESUMO

Accumulating data suggest that ribosomal protein S6 kinase 1 (S6K1), an effector in the mammalian target of rapamycin (mTOR) pathway, plays pleiotropic roles in tumor progression. However, to date, while the tumorigenic function of S6K1 in tumor cells has been well elucidated, its role in the tumor stroma remains poorly understood. We recently showed that S6K1 mediates vascular endothelial growth factor A (VEGF-A) production in macrophages, thereby supporting tumor angiogenesis and growth. As macrophage-derived VEGF-A is crucial for both tumor cell intravasation and extravasation across the vascular endothelium, our previous findings suggest that stromal S6K1 signaling is required for tumor metastatic spread. Therefore, we aimed to determine the impact of host S6K1 depletion on tumor metastasis using a murine model of pulmonary metastasis (S6k1-/- mice implanted with B16F10 melanoma). The ablation of S6K1 in the host microenvironment significantly reduced the metastasized B16F10 melanoma cells on the lung surface in both spontaneous and intravenous lung metastasis mouse models without affecting the incidence of metastasis to distant lymph nodes. In addition, stromal S6K1 loss decreased the number of tumor cells circulating in the peripheral blood of mice bearing B16F10 xenografts without affecting the vascular leakage induced by VEGF-A in vivo. These observations demonstrate that S6K1 signaling in host cells other than endothelial cells is required to modulate the host microenvironment to facilitate the metastatic spread of tumors via blood circulation, thus revealing its novel role in the tumor stroma during tumor progression.


Assuntos
Neoplasias Pulmonares , Melanoma , Proteínas Quinases S6 Ribossômicas 90-kDa , Animais , Humanos , Camundongos , Células Endoteliais/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Mamíferos/metabolismo , Melanoma/metabolismo , Melanoma/patologia , Transdução de Sinais , Microambiente Tumoral , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo
2.
BMC Infect Dis ; 24(1): 259, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402154

RESUMO

BACKGROUND: While there is a high burden of methicillin-resistant Staphylococcus aureus (MRSA) infections among pediatric patients, studies on the molecular epidemiology of MRSA infections in Korean children since the 2010s are lacking. This study aimed to investigate the molecular genotypes and clinical characteristics of MRSA isolates from children with MRSA bacteremia at Asan Medical Center Children's Hospital from 2016 to 2021. METHODS: Clinical data were retrospectively reviewed, and the molecular types of MRSA were determined using multilocus sequence typing (MLST) and Staphylococcal cassette chromosome mec (SCCmec) typing. RESULTS: The overall methicillin resistance rate of S. aureus bacteremia was 44.8% (77/172); 49.5% in the period 2016-2018 (period 1) and 37.3% in the period 2019-2021 (period 2) (P = 0.116). Community-acquired infections accounted for only 3.9% of cases. The predominant ST group was ST72 group (67.6%), followed by ST5 group (18.9%) and ST1 group (5.4%). The proportion of ST5 was significantly lower in period 2 compared to period 1 (P = 0.02). Compared to the ST5 and ST1 groups, the ST72 group exhibited lower overall antibiotic resistance and multidrug-resistant (MDR) rates (12.0% [6/50] in ST72 group vs. 100.0% [14/14] in ST5 group vs. 50.0% [2/4] in ST1 group; P < 0.001). In the multivariate analysis, the ST1 group was an independent risk factor for 30-day all-cause mortality (aOR, 44.12; 95% CI, 3.46-562.19). CONCLUSION: The ST72-MRSA strain remained the most frequently isolated genotype in Korean children, while the ST1 group emerged as an independent risk factor for 30-day all-cause mortality in pediatric MRSA bacteremia. Ongoing efforts to uncover the evolving epidemiology of MRSA are essential for developing effective strategies for prevention and treatment.


Assuntos
Bacteriemia , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Criança , Staphylococcus aureus , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Estudos Retrospectivos , Infecções Estafilocócicas/epidemiologia , Testes de Sensibilidade Microbiana , Bacteriemia/epidemiologia , Genótipo , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
3.
J Korean Med Sci ; 39(15): e136, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38651222

RESUMO

BACKGROUND: Haemophilus influenzae is a frequently encountered pathogen responsible for respiratory tract infections in children. Following the detection of ceftriaxone-resistant H. influenzae at our institution, we aimed to investigate the resistance mechanisms of ceftriaxone in H. influenzae, with a particular focus on alterations in penicillin-binding protein 3 (PBP3) and ß-lactamase production. METHODS: Among H. influenzae isolates collected at Asan Medical Center Children's Hospital from March 2014 to April 2019, ceftriaxone-resistant strains by the disk-diffusion test were included. Ceftriaxone minimum inhibitory concentrations (MICs) were determined using the E-test according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines. The presence of ß-lactamase was assessed through cefinase test and TEM-1/ROB-1 polymerase chain reaction (PCR). PBP3 alterations were explored via ftsI gene sequencing. RESULTS: Out of the 68 collected strains, 21 exhibited resistance to ceftriaxone in disk diffusion tests. Two strains were excluded due to failed subculture. Among 19 ceftriaxone-resistant H. influenzae isolates, eighteen were non-typeable H. influenzae, and twelve were positive for TEM-1 PCR. Isolates were classified into groups II (harboring only N526K, n = 3), III (N526K+S385T, n = 2), III+ (S385T+L389F+N526K, n = 11), and III-like+ (S385T+L389F+R517H, n = 3) according to the PBP3 alteration pattern. With a median ceftriaxone MIC of 0.190 mg/L (range, 0.008-0.750), the median ceftriaxone MIC was the highest in group III-like+ (0.250 mg/L), followed by groups III+ (0.190 mg/L), III (0.158 mg/L), and II (0.012 mg/L). All three strains belonging to group II, which did not harbor the S385T substitution, had ceftriaxone MICs of ≤ 0.125 mg/L. CONCLUSION: The emergence of ceftriaxone-resistant H. influenzae with ceftriaxone MIC values of up to 0.75 mg/L was observed even in children in South Korea, with most associated with S385T and L389F substitutions. The N526K mutation alone does not significantly impact ceftriaxone resistance. Further large-scale studies are essential to investigate changes in antibiotic resistance patterns and factors influencing antibiotic resistance in H. influenzae isolated from pediatric patients in Korea.


Assuntos
Antibacterianos , Ceftriaxona , Infecções por Haemophilus , Haemophilus influenzae , Testes de Sensibilidade Microbiana , beta-Lactamases , Ceftriaxona/farmacologia , Haemophilus influenzae/efeitos dos fármacos , Haemophilus influenzae/isolamento & purificação , Haemophilus influenzae/genética , Humanos , Antibacterianos/farmacologia , República da Coreia , beta-Lactamases/genética , beta-Lactamases/metabolismo , Criança , Infecções por Haemophilus/microbiologia , Infecções por Haemophilus/tratamento farmacológico , Proteínas de Ligação às Penicilinas/genética , Pré-Escolar , Farmacorresistência Bacteriana , Lactente , Feminino , Masculino , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
4.
J Korean Med Sci ; 38(33): e252, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37605494

RESUMO

BACKGROUND: Ralstonia mannitolilytica is a causative organism of nosocomial infections, particularly associated with contaminated water, and resistant to various antibiotics, including carbapenems. Several clusters of R. mannitolilytica infections appeared in children at our institute from August 2018 to November 2019. METHODS: From March 2009 to March 2023, all patients admitted to Asan Medical Center Children's Hospital in Seoul, Korea, with culture-confirmed R. mannitolilytica and corresponding clinical signs of infection were identified. Epidemiological and environmental investigations were conducted. Polymerase chain reaction (PCR) was performed for the genes of OXA-443 and OXA-444 on R. mannitolilytica isolates. RESULTS: A total of 18 patients with R. mannitolilytica infection were included in this study, with 94.4% (17/18) and 5.6% (1/18) being diagnosed with pneumonia and central line-associated bloodstream infection, respectively. All-cause 30-day mortality rate was 61.1% (11/18), and seven of the fatal cases were caused by R. mannitolilytica infection itself. The resistance rates to meropenem and imipenem werew 94.4% (17/18) and 5.6% (1/18), respectively. Although four out of nine meropenem-resistant R. mannitolilytica isolates had positive PCR results for OXA-443 and OXA-444 genes, there were no significant differences in antimicrobial susceptibility patterns. Environmental sampling identified R. mannitolylica at two sites: a cold-water tap of a water purifier and an exhalation circuit of a patient mechanical ventilator. After implementing and improving adherence to infection control policies, no additional R. mannitolilytica infection cases have been reported since December 2019. CONCLUSION: R. mannitolilytica can cause life-threatening infections with high mortality in fragile pediatric populations. To prevent outbreaks, healthcare workers should be aware of R. mannitolilytica infections and strive to comply with infection control policies.


Assuntos
Antibacterianos , Surtos de Doenças , Humanos , Criança , Meropeném/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Hospitais Pediátricos
5.
Sensors (Basel) ; 23(12)2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37420693

RESUMO

Solubility measurements are essential in various research and industrial fields. With the automation of processes, the importance of automatic and real-time solubility measurements has increased. Although end-to-end learning methods are commonly used for classification tasks, the use of handcrafted features is still important for specific tasks with the limited labeled images of solutions used in industrial settings. In this study, we propose a method that uses computer vision algorithms to extract nine handcrafted features from images and train a DNN-based classifier to automatically classify solutions based on their dissolution states. To validate the proposed method, a dataset was constructed using various solution images ranging from undissolved solutes in the form of fine particles to those completely covering the solution. Using the proposed method, the solubility status can be automatically screened in real time by using a display and camera on a tablet or mobile phone. Therefore, by combining an automatic solubility changing system with the proposed method, a fully automated process could be achieved without human intervention.


Assuntos
Algoritmos , Redes Neurais de Computação , Humanos , Solubilidade , Automação
6.
Pain Pract ; 23(1): 123-126, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35638334

RESUMO

BACKGROUND: Lumbar spinal stenosis is a common degenerative disease that causes low back and lower-extremity pain that increases with age. The treatment of lumbar spinal stenosis is either conservative or surgical. ESI is a commonly performed conservative treatment, but evidence of its effectiveness in lumbar spinal stenosis is limited. CASE SERIES: We encountered the three patients with back pain and claudication due to lumbar spinal stenosis, which could not be controlled by conservative therapy including ESIs. Trimacinolone acetonide was injected into the patients' ligamentum flavum. All patients experienced dramatic improvement in their symptoms. CONCLUSIONS: Trimacinolone acetonide injection into the ligamentum flavum may be effective for lumbar spinal stenosis that does not improve with ESIs.


Assuntos
Ligamento Amarelo , Dor Intratável , Estenose Espinal , Humanos , Estenose Espinal/complicações , Estenose Espinal/tratamento farmacológico , Manejo da Dor/métodos , Esteroides/uso terapêutico , Vértebras Lombares/cirurgia
7.
Proc Natl Acad Sci U S A ; 116(39): 19288-19293, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31501346

RESUMO

Bacterial cellulose nanofiber (BCNF) with high thermal stability produced by an ecofriendly process has emerged as a promising solution to realize safe and sustainable materials in the large-scale battery. However, an understanding of the actual thermal behavior of the BCNF in the full-cell battery has been lacking, and the yield is still limited for commercialization. Here, we report the entire process of BCNF production and battery manufacture. We systematically constructed a strain with the highest yield (31.5%) by increasing metabolic flux and improved safety by introducing a Lewis base to overcome thermochemical degradation in the battery. This report will open ways of exploiting the BCNF as a "single-layer" separator, a good alternative to the existing chemical-derived one, and thus can greatly contribute to solving the environmental and safety issues.

8.
Bioorg Med Chem ; 45: 116312, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34332211

RESUMO

Phosphatidylinositol 3-kinases (PI3Ks) mediate intracellular signal transduction. Aberrant PI3K signaling is associated with oncogenesis and disease progression in solid tumors and hematologic malignancies. Idelalisib (1), a first-in-class PI3Kδ inhibitor for the treatment of hematologic malignancies, was developed, but its sales were limited by black box warnings due to unexpected adverse effects. Therefore, to overcome these adverse events, various quinazolinone derivatives were synthesized and evaluated in vitro based on their inhibitory activity against the PI3K enzyme and the viability of cell lines such as MOLT and SUDHL. Among them, 6f (IC50 = 0.39 nM) and 6m (IC50 = 0.09 nM) showed excellent enzyme activity, and 6m displayed an approximately four-fold higher selectivity for PI3Kγ/δ compared with Idelalisib (1). Furthermore, in vivo PK experiments with 6f and 6m revealed that 6f (AUClast = 81.04 h*ng/mL, Cmax = 18.34 ng/mL, Tmax = 0.5 h, t1/2 = 10.2 h in 1 mpk dose) had improved PK compared with 1. Finally, further experiments will be conducted with 6f selected as a candidate, and the potential for it to be developed as a treatment with good efficacy for hematologic malignancies will be determined.


Assuntos
Antineoplásicos/farmacologia , Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Neoplasias Hematológicas/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Purinas/farmacologia , Quinazolinonas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias Hematológicas/metabolismo , Neoplasias Hematológicas/patologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Inibidores de Fosfoinositídeo-3 Quinase/síntese química , Inibidores de Fosfoinositídeo-3 Quinase/química , Purinas/química , Quinazolinonas/síntese química , Quinazolinonas/química , Relação Estrutura-Atividade
9.
J Korean Med Sci ; 36(36): e246, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34519187

RESUMO

In 2017, the Korean government launched an unprecedentedly large-scaled latent tuberculosis infection (LTBI) screening project which covered more than a million individuals in congregate settings. A total of 1,047,689 participants of source population (n = 2,336,157) underwent LTBI testing from 2017 to 2018. The overall LTBI test uptake rate during this project was 44.8%. Workers in daycare centers (83.5%) and kindergartens (78.9%) showed high participation rate. A total of 1,012,206 individuals with valid results of interferon-gamma release assay (IGRA) were selected to constitute the IGRA cohort. Most of the enrolled participants in the IGRA cohort were in their working age. Approximately, three-quarters of total enrolled population were female. Investigating the LTBI prevalence, stages of LTBI care cascade, natural history of LTBI, efficacy of LTBI treatment and cost-effectiveness of LTBI screening are feasible within this IGRA cohort.


Assuntos
Testes de Liberação de Interferon-gama/métodos , Tuberculose Latente/diagnóstico , Programas de Rastreamento/economia , Adulto , Antituberculosos/uso terapêutico , Estudos de Coortes , Análise Custo-Benefício , Feminino , Humanos , Tuberculose Latente/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Prevalência , República da Coreia
10.
Int J Mol Sci ; 20(16)2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31412537

RESUMO

In this study, we synthesized a Zr-89-labeled anti-adenosine triphosphate synthase monoclonal antibody (ATPS mAb) for applications in immuno-positron emission tomography (PET) and evaluated its feasibility for angiogenesis imaging. The cellular uptake of Zr-89 ATPS mAb was measured after treatment of cancer cell lines in vitro, and its biodistribution was evaluated at 4, 24 and 48 h in vivo in mice bearing xenografts. PET images were acquired at 4, 24, 48, and 96 h after Zr-89 ATPS mAb administration. Tumor angiogenesis was analyzed using anti-CD31 immunofluorescence staining. The cellular uptake of Zr-89 ATPS mAb increased over time in MDA-MB-231 breast cancer cells but did not increase in PC3 prostate cancer cells. The tumor uptake of Zr-89 ATPS mAb at 24 h was 9.4 ± 0.9% ID/g for MDA-Mb-231 cells and was 3.8 ± 0.6% ID/g for PC3 cells (p = 0.004). Zr-89 ATPS mAb uptake in MDA-MB-231 xenografts was inhibited by the administration of cold ATPS mAb (4.4 ± 0.5% ID/g, p = 0.011). Zr-89 ATPS mAb uptake could be visualized by PET for up to 96 h in MDA-MB-231 tumors. In contrast, there was no distinct tumor uptake detected by PET in the PC3 xenograft model. CD31-positive tumor vessels were abundant in MDA-MB-231 tumors, whereas they were scarcely detected in PC3 tumors. In conclusion, ATPS mAb was successfully labeled with Zr-89, which could be used for immuno-PET imaging targeting tumor angiogenesis.


Assuntos
Trifosfato de Adenosina , Imagem Molecular , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Neovascularização Patológica/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Radioisótopos , Compostos Radiofarmacêuticos , Zircônio , Trifosfato de Adenosina/metabolismo , Animais , Anticorpos Monoclonais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Xenoenxertos , Humanos , Imunoconjugados , Masculino , Camundongos , Imagem Molecular/métodos , Tomografia por Emissão de Pósitrons/métodos , Radioisótopos/química , Radioisótopos/metabolismo , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/metabolismo , Distribuição Tecidual , Zircônio/química , Zircônio/metabolismo
11.
J Phys Ther Sci ; 30(8): 958-959, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30154580

RESUMO

[Purpose] The purpose of this research was to examine differences in muscle activity between the resting forearm position (RFP) and the straight forearm position (SFP) during upper arm strengthening exercises. [Participants and Methods] In total, 35 healthy college students were randomly sampled (18 males and 17 females). Surface electromyography data were collected from the medial and lateral sides of the biceps and triceps brachii muscles. [Results] The medial muscles showed greater activity during SFP versus RFP, but no difference in overall activation was found between the two positions. [Conclusion] Carrying angle less affected to biceps and triceps brachii muscles activation during upper arm strengthening exercises.

12.
Food Microbiol ; 61: 72-82, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27697172

RESUMO

Prokaryotes were extracted from skates and fermented skates purchased from fish markets and a local manufacturer in South Korea. The prokaryotic community composition of skates and fermented skates was investigated using 16S rRNA pyrosequencing. The ranges for pH and salinity of the grinded tissue extract from fermented skates were 8.4-8.9 and 1.6-6.6%, respectively. Urea and ammonia concentrations were markedly low and high, respectively, in fermented skates compared to skates. Species richness was increased in fermented skates compared to skates. Dominant and predominant bacterial groups present in the fermented skates belonged to the phylum Firmicutes, whereas those in skates belonged to Gammaproteobacteria. The major taxa found in Firmicutes were Atopostipes (Carnobacteriaceae, Lactobacillales) and/or Tissierella (Tissierellaceae, Tissierellales). A combination of RT-PCR and pyrosequencing for active bacterial composition showed that the dominant taxa i.e., Atopostipes and Tissierella, were active in fermented skate. Those dominant taxa are possibly marine lactic acid bacteria. Marine bacteria of the taxa Lactobacillales and/or Clostridia seem to be important in alkaline fermentation of skates.


Assuntos
Bactérias/isolamento & purificação , Fermentação , Consórcios Microbianos , Alimentos Marinhos/microbiologia , Rajidae/microbiologia , Animais , Bactérias/classificação , Bactérias/genética , Clostridium/genética , Clostridium/isolamento & purificação , Firmicutes/genética , Firmicutes/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Concentração de Íons de Hidrogênio , Lactobacillales/genética , Lactobacillales/isolamento & purificação , Consórcios Microbianos/genética , República da Coreia
13.
Langmuir ; 30(41): 12164-70, 2014 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-25226338

RESUMO

We study electrostatic interactions of polystyrene particles at an oil/water interface controlled by a chemical reaction of carboxylate surface functional groups. By replacing the carboxyl functional groups with hydrocarbon chains using the well-known EDC (1-ethyl-3-(3-(dimethylamino)propyl)carbodiimide) coupling reaction, the surface charge density decreases while the hydrophobicity of the colloid surface increases. Direct visualization of the particle-laden interface reveals that, depending on the extent of hydrocarbon coupling, the strength of the electrostatic repulsion can be regulated: the repulsive interaction increases with the reaction, removing aggregates, but rapidly decreases if the reaction proceeds too much, forming a large aggregation. This simple reaction, thus, dramatically changes the structures of the colloidal monolayers at the oil/water interface. We conclude that such structural change is the result of change of the repulsive interactions from the oil phase, although interactions in the water phase are also changed slightly.

14.
Pharmaceuticals (Basel) ; 16(9)2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37765069

RESUMO

Artificial intelligence (AI) has permeated various sectors, including the pharmaceutical industry and research, where it has been utilized to efficiently identify new chemical entities with desirable properties. The application of AI algorithms to drug discovery presents both remarkable opportunities and challenges. This review article focuses on the transformative role of AI in medicinal chemistry. We delve into the applications of machine learning and deep learning techniques in drug screening and design, discussing their potential to expedite the early drug discovery process. In particular, we provide a comprehensive overview of the use of AI algorithms in predicting protein structures, drug-target interactions, and molecular properties such as drug toxicity. While AI has accelerated the drug discovery process, data quality issues and technological constraints remain challenges. Nonetheless, new relationships and methods have been unveiled, demonstrating AI's expanding potential in predicting and understanding drug interactions and properties. For its full potential to be realized, interdisciplinary collaboration is essential. This review underscores AI's growing influence on the future trajectory of medicinal chemistry and stresses the importance of ongoing synergies between computational and domain experts.

15.
J Liver Cancer ; 23(2): 341-349, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37488925

RESUMO

BACKGROUND/AIM: Cancer-associated fibroblasts (CAFs) play an immunosuppressive role in the tumor microenvironment (TME) of human cancers; however, their characteristics and role in hepatocellular carcinoma (HCC) remain to be elucidated. METHODS: Nine tumor and surrounding liver tissue samples from patients with HCC who underwent surgery were used to isolate patient-derived CAFs. Cell morphology was observed using an optical microscope after culture, and cell phenotypes were evaluated using flow cytometry and immunoblotting. Cytokines secreted by CAFs into culture medium were quantified using a multiplex cytokine assay. RESULTS: CAFs were abundant in the TME of HCC and were adjacent to immune cells. After culture, the CAFs and non-tumor fibroblasts exhibited spindle shapes. We observed a robust expression of alpha-smooth muscle actin and fibroblast activation protein in CAFs, whereas alpha-fetoprotein, epithelial cell adhesion molecule, platelet/endothelial cell adhesion molecule-1, and E-cadherin were not expressed in CAFs. Furthermore, CAFs showed high secretion of various cytokines, namely C-X-C motif chemokine ligand 12, interleukin (IL)-6, IL-8, and C-C motif chemokine ligand 2. CONCLUSIONS: CAFs are abundant in the TME of HCC and play a crucial role in tumor progression. These fibroblasts secrete cytokines that promote tumor growth and metastasis.

16.
Sci Adv ; 9(44): eadj0461, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37910607

RESUMO

The automation of organic compound synthesis is pivotal for expediting the development of such compounds. In addition, enhancing development efficiency can be achieved by incorporating autonomous functions alongside automation. To achieve this, we developed an autonomous synthesis robot that harnesses the power of artificial intelligence (AI) and robotic technology to establish optimal synthetic recipes. Given a target molecule, our AI initially plans synthetic pathways and defines reaction conditions. It then iteratively refines these plans using feedback from the experimental robot, gradually optimizing the recipe. The system performance was validated by successfully determining synthetic recipes for three organic compounds, yielding that conversion rates that outperform existing references. Notably, this autonomous system is designed around batch reactors, making it accessible and valuable to chemists in standard laboratory settings, thereby streamlining research endeavors.

17.
Bioconjug Chem ; 23(10): 2114-20, 2012 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-23025585

RESUMO

New zwitterionic polymer-coated immunoaffinity beads were developed to resist nonspecific protein adsorption from undiluted human serum for diagnostic applications of exosomes. A zwitterionic sulfobetaine monomer with an amine functional group was employed for simple surface chemistry and antifouling properties. An exosomal biomarker protein, epithelial cell adhesion molecule (EpCAM), was selected as a target molecule in this work. The beads were coated with polyacrylic acids (PAA) for increasing biorecognition sites, and protein G was then conjugated with carboxylic acid groups on the surfaces for controlling EpCAM antibody orientation. The remaining free carboxylic acid groups were modified with sulfobetaine moieties, and anti-EpCAM antibody was finally introduced. The amount of anti-EpCAM on the beads was increased by 40% when compared with PAA-uncoated beads. The surfaces of the beads exhibited near-net-zero charge, and nonspecific protein adsorption was effectively suppressed by sulfobetaine moieties. EpCAM was captured from undiluted human serum with almost the same degree of efficiency as from PBS buffer solution using the newly developed immunoaffinity beads.


Assuntos
Resinas Acrílicas/química , Anticorpos/química , Fracionamento Celular/métodos , Exossomos/metabolismo , Adsorção , Anticorpos/imunologia , Antígenos de Neoplasias/imunologia , Moléculas de Adesão Celular/imunologia , Molécula de Adesão da Célula Epitelial , Humanos , Imãs/química , Microesferas , Propriedades de Superfície
18.
Anal Biochem ; 431(2): 96-8, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22982508

RESUMO

A direct extraction method was developed for exosomal microRNAs. After isolation of exosomes from human serum by immunoaffinity magnetic beads, microRNAs were extracted by just mixing beads with a lysis solution and heating without further purification. The lysis solution was composed of a nonionic detergent and salt (NaCl). The concentration of each component was optimized to maximize lysis efficiency and to inhibit adsorption of extracted microRNAs on beads. MicroRNAs extracted by this method could be quantitatively analyzed by qRT-PCR, indicating that the method could replace conventional methods for extracting microRNAs from immunobead-captured exosomes.


Assuntos
Exossomos , Separação Imunomagnética/métodos , MicroRNAs/isolamento & purificação , Exossomos/metabolismo , Exossomos/ultraestrutura , Humanos , MicroRNAs/sangue
19.
Biomater Res ; 26(1): 58, 2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36273198

RESUMO

BACKGROUND: Recombinant tissue plasminogen activator (rtPA) has a short half-life, and additional hemorrhagic transformation (HT) can occur when treatment is delayed. Here, we report the design and thrombolytic performance of 3 [Formula: see text]m discoidal polymeric particles loaded with rtPA and superparamagnetic iron oxide nanoparticles (SPIONs), referred to as rmDPPs, to address the HT issues of rtPA. METHODS: The rmDPPs consisted of a biodegradable polymeric matrix, rtPA, and SPIONs and were synthesized via a top-down fabrication. RESULTS: The rmDPPs could be concentrated at the target site with magnetic attraction, and then the rtPA could be released under acoustic stimulus. Therefore, we named that the particles had magnetoacoustic properties. For the in vitro blood clot lysis, the rmDPPs with magnetoacoustic stimuli could not enhance the lytic potential compared to the rmDPPs without stimulation. Furthermore, although the reduction of the infarcts in vivo was observed along with the magnetoacoustic stimuli in the rmDPPs, more enhancement was not achieved in comparison with the rtPA. A notable advantage of rmDPPs was shown in delayed administration of rmDPPs at poststroke. The late treatment of rmDPPs with magnetoacoustic stimuli could reduce the infarcts and lead to no additional HT issues, while rtPA alone could not show any favorable prognosis. CONCLUSION: The rmDPPs may be advantageous in delayed treatment of thrombotic patients.

20.
Int J Nanomedicine ; 17: 6317-6334, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36536939

RESUMO

Background: Ototoxicity currently has no available treatment other than medication withdrawal as soon as toxicity is suspected. The human inner ear organs have little potential for regeneration; thus, ototoxicity-induced hair cell injury is deemed permanent. Dexamethasone (Dexa) is a synthetic steroid analog that has significant potential for otoprotection in the treatment of various inner ear diseases; however, its low absorption into the inner ear prevents significant recovery of function. Nanoparticles facilitate targeted drug delivery, stabilize drug release, and increase half-life of the drug. Methods: This study aimed to develop poly(lactic-co-glycolic acid) (PLGA) nanoparticles loaded superparamagnetic iron oxide nanoparticles (SPIONs) and Dexa (PSD-NPs) to control localized drug delivery by magnetic attraction in the treatment of ototoxicity-induced hearing loss. PSD-NPs and without SPIONs (PD-NPs) were prepared using a nanoprecipitation method. Results: Using an inner ear simulating system, we confirmed that PSD-NPs has an otoprotective effect in organotypic culture that is enhanced by magnetic attraction. PSD-NPs delivered via intrabullar injection in a magnetic field penetrated the inner ear and prevented hearing loss progression to a greater degree than equivalent doses of Dexa or PSD-NPs alone (day 28: ototoxic: 80.0 ± 0.0 dB; Dexa 100: 60.0 ± 15.5 dB; PSD 100: 50.0 ± 8.2 dB; PSD 100 with magnet: 22.5 ± 5.0 dB; P < 0.05). The protective effects were confirmed in various in vivo and in vitro models of ototoxicity. Conclusion: Our findings suggest that SPIONs with Dexa and magnetic field application prevent the progression of ototoxicity-induced hearing loss through anti-apoptotic mechanisms in the inner ear.


Assuntos
Perda Auditiva , Nanopartículas , Ototoxicidade , Camundongos , Humanos , Animais , Modelos Animais de Doenças , Nanopartículas Magnéticas de Óxido de Ferro , Dexametasona/farmacologia , Fenômenos Magnéticos
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