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1.
ACS Nano ; 18(34): 23217-23231, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39141004

RESUMO

Flexible fiber-based microelectrodes allow safe and chronic investigation and modulation of electrically active cells and tissues. Compared to planar electrodes, they enhance targeting precision while minimizing side effects from the device-tissue mechanical mismatch. However, the current manufacturing methods face scalability, reproducibility, and handling challenges, hindering large-scale deployment. Furthermore, only a few designs can record electrical and biochemical signals necessary for understanding and interacting with complex biological systems. In this study, we present a method that utilizes the electrical conductivity and easy processability of MXenes, a diverse family of two-dimensional nanomaterials, to apply a thin layer of MXene coating continuously to commercial nylon filaments (30-300 µm in diameter) at a rapid speed (up to 15 mm/s), achieving a linear resistance below 10 Ω/cm. The MXene-coated filaments are then batch-processed into free-standing fiber microelectrodes with excellent flexibility, durability, and consistent performance even when knotted. We demonstrate the electrochemical properties of these fiber electrodes and their hydrogen peroxide (H2O2) sensing capability and showcase their applications in vivo (rodent) and ex vivo (bladder tissue). This scalable process fabricates high-performance microfiber electrodes that can be easily customized and deployed in diverse bioelectronic monitoring and stimulation studies, contributing to a deeper understanding of health and disease.


Assuntos
Peróxido de Hidrogênio , Microeletrodos , Peróxido de Hidrogênio/química , Animais , Bexiga Urinária , Condutividade Elétrica , Ratos , Técnicas Eletroquímicas/instrumentação , Nanoestruturas/química
2.
Sens Diagn ; 3(8): 1310-1318, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39129860

RESUMO

MicroRNAs (miRNAs) are short (about 18-24 nucleotides) non-coding RNAs and have emerged as potential biomarkers for various diseases, including cancers. Due to their short lengths, the specificity often becomes an issue in conventional amplification-based methods. Next-generation sequencing techniques could be an alternative, but the long analysis time and expensive costs make them less suitable for routine clinical diagnosis. Therefore, it is essential to develop a rapid, selective, and accurate miRNA detection assay using a simple, affordable system. In this work, we report a CRISPR/Cas13a-based miRNA biosensing using point-of-care dark-field (DF) imaging. We utilized magnetic-gold nanoparticle (MGNPs) complexes as signal probes, which consist of 200 nm-sized magnetic beads and 60 nm-sized gold nanoparticles (AuNPs) linked by DNA hybridization. Once the CRISPR/Cas13a system recognized the target miRNAs (miR-21-5p), the activated Cas13a cleaved the bridge linker containing RNA sequences, releasing 60 nm-AuNPs detected and quantified by a portable DF imaging system. The combination of CRISPR/Cas13a, MGNPs, and DF imaging demonstrated amplification-free detection of miR-21-5p within 30 min at a detection limit of 500 attomoles (25 pM) and with single-base specificity. The CRISPR/Cas13a-assisted MGNP-DF assay achieved rapid, selective, and accurate detection of miRNAs with simple equipment, thus providing a potential application for cancer diagnosis.

3.
Nat Commun ; 15(1): 6271, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39054353

RESUMO

Addressing the global disparity in cancer care necessitates the development of rapid and affordable nucleic acid (NA) testing technologies. This need is particularly critical for cervical cancer, where molecular detection of human papillomavirus (HPV) has emerged as an accurate screening method. However, implementing this transition in low- and middle-income countries has been challenging due to the high costs and centralized facilities required for current NA tests. Here, we present CreDiT (CRISPR Enhanced Digital Testing) for on-site NA detection. The CreDiT platform integrates i) a one-pot CRISPR strategy that simultaneously amplifies both target NAs and analytical signals and ii) a robust fluorescent detection based on digital communication (encoding/decoding) technology. These features enable a rapid assay (<35 minutes) in a single streamlined workflow. We demonstrate the sensitive detection of cell-derived HPV DNA targets down to single copies and accurate identification of HPV types in clinical cervical brushing specimens (n = 121).


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/virologia , Neoplasias do Colo do Útero/genética , Feminino , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/virologia , Sistemas CRISPR-Cas/genética , DNA Viral/genética , Papillomaviridae/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Processamento de Sinais Assistido por Computador , Colo do Útero/virologia
4.
ACS Appl Mater Interfaces ; 16(29): 38243-38251, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38980927

RESUMO

Development of efficient portable sensors for accurately detecting biomarkers is crucial for early disease diagnosis, yet remains a significant challenge. To address this need, we introduce the enhanced luminescence lateral-flow assay, which leverages highly luminescent upconverting nanoparticles (UCNPs) alongside a portable reader and a smartphone app. The sensor's efficiency and versatility were shown for kidney health monitoring as a proof of concept. We engineered Er3+- and Tm3+-doped UCNPs coated with multiple layers, including an undoped inert matrix shell, a mesoporous silica shell, and an outer layer of gold (UCNP@mSiO2@Au). These coatings synergistically enhance emission by over 40-fold and facilitate biomolecule conjugation, rendering UCNP@mSiO2@Au easy to use and suitable for a broad range of bioapplications. Employing these optimized nanoparticles in lateral-flow assays, we successfully detected two acute kidney injury-related biomarkers─kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL)─in urine samples. Using our sensor platform, KIM-1 and NGAL can be accurately detected and quantified within the range of 0.1 to 20 ng/mL, boasting impressively low limits of detection at 0.28 and 0.23 ng/mL, respectively. Validating our approach, we analyzed clinical urine samples, achieving biomarker concentrations that closely correlated with results obtained via ELISA. Importantly, our system enables biomarker quantification in less than 15 min, underscoring the performance of our novel UCNP-based approach and its potential as reliable, rapid, and user-friendly diagnostics.


Assuntos
Biomarcadores , Ouro , Receptor Celular 1 do Vírus da Hepatite A , Lipocalina-2 , Nanopartículas , Humanos , Biomarcadores/urina , Lipocalina-2/urina , Receptor Celular 1 do Vírus da Hepatite A/análise , Ouro/química , Nanopartículas/química , Érbio/química , Injúria Renal Aguda/urina , Injúria Renal Aguda/diagnóstico , Dióxido de Silício/química , Túlio/química , Medições Luminescentes/métodos , Luminescência , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Limite de Detecção
5.
Biomolecules ; 14(7)2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-39062520

RESUMO

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is the most prevalent genetic kidney disorder. While metformin has demonstrated the ability to inhibit cyst growth in animal models of ADPKD via activation of adenosine monophosphate-activated protein kinase (AMPK), its effectiveness in humans is limited due to its low potency. This study explored the impact of HL156A, a new and more potent AMPK activator, in a mouse model of ADPKD. METHODS: To investigate whether HL156A inhibits the proliferation of renal cyst cells in ADPKD in vitro, exogenous human telomerase reverse transcriptase (hTERT)-immortalized renal cyst cells from ADPKD patients were treated with HL156A, and an MTT (dimethylthiazol-diphenyltetrazolium bromide) assay was performed. To assess the cyst-inhibitory effect of HL156A in vivo, we generated Pkd1 conditional knockout (KO) mice with aquaporin 2 (AQP2)-Cre, which selectively expresses Cre recombinase in the collecting duct. The effectiveness of HL156A in inhibiting cyst growth and improving renal function was confirmed by measuring the number of cysts and blood urea nitrogen (BUN) levels in the collecting duct-specific Pkd1 KO mice. RESULTS: When cyst cells were treated with up to 20 µM of metformin or HL156A, HL156A reduced cell viability by 25% starting at a concentration of 5 µM, whereas metformin showed no effect. When AQP2-Cre male mice were crossed with Pkd1flox/flox female mice, and when AQP2-Cre female mice were crossed with Pkd1flox/flox male mice, the number of litters produced by both groups was comparable. In collecting duct-specific Pkd1 KO mice, HL156A was found to inhibit cyst growth, reducing both the number and size of cysts. Furthermore, it was confirmed that kidney function improved as HL156A treatment led to a reduction in elevated BUN levels. Lastly, it was observed that the increase in AMPK phosphorylation induced by HL156A decreased ERK phosphorylation and α-SMA expression. CONCLUSION: HL156A has potential as a drug that can restore kidney function in ADPKD patients by inhibiting cyst growth.


Assuntos
Proteínas Quinases Ativadas por AMP , Rim Policístico Autossômico Dominante , Animais , Rim Policístico Autossômico Dominante/tratamento farmacológico , Rim Policístico Autossômico Dominante/metabolismo , Rim Policístico Autossômico Dominante/patologia , Rim Policístico Autossômico Dominante/genética , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Humanos , Camundongos Knockout , Proliferação de Células/efeitos dos fármacos , Masculino , Modelos Animais de Doenças , Cistos/tratamento farmacológico , Cistos/patologia , Cistos/metabolismo
6.
Oncol Res ; 32(6): 1021-1030, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827321

RESUMO

Background: Apolipoprotein B mRNA editing catalytic polypeptide (APOBEC), an endogenous mutator, induces DNA damage and activates the ataxia telangiectasia and Rad3-related (ATR)-checkpoint kinase 1 (Chk1) pathway. Although cisplatin-based therapy is the mainstay for muscle-invasive bladder cancer (MIBC), it has a poor survival rate. Therefore, this study aimed to evaluate the efficacy of an ATR inhibitor combined with cisplatin in the treatment of APOBEC catalytic subunit 3B (APOBEC3B) expressing MIBC. Methods: Immunohistochemical staining was performed to analyze an association between APOBEC3B and ATR in patients with MIBC. The APOBEC3B expression in MIBC cell lines was assessed using real-time polymerase chain reaction and western blot analysis. Western blot analysis was performed to confirm differences in phosphorylated Chk1 (pChk1) expression according to the APOBEC3B expression. Cell viability and apoptosis analyses were performed to examine the anti-tumor activity of ATR inhibitors combined with cisplatin. Conclusion: There was a significant association between APOBEC3B and ATR expression in the tumor tissues obtained from patients with MIBC. Cells with higher APOBEC3B expression showed higher pChk1 expression than cells expressing low APOBEC3B levels. Combination treatment of ATR inhibitor and cisplatin inhibited cell growth in MIBC cells with a higher APOBEC3B expression. Compared to cisplatin single treatment, combination treatment induced more apoptotic cell death in the cells with higher APOBEC3B expression. Conclusion: Our study shows that APOBEC3B's higher expression status can enhance the sensitivity of MIBC to cisplatin upon ATR inhibition. This result provides new insight into appropriate patient selection for the effective application of ATR inhibitors in MIBC.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia , Cisplatino , Citidina Desaminase , Antígenos de Histocompatibilidade Menor , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Citidina Desaminase/genética , Citidina Desaminase/metabolismo , Linhagem Celular Tumoral , Masculino , Antígenos de Histocompatibilidade Menor/metabolismo , Antígenos de Histocompatibilidade Menor/genética , Pessoa de Meia-Idade , Feminino , Quinase 1 do Ponto de Checagem/metabolismo , Quinase 1 do Ponto de Checagem/antagonistas & inibidores , Quinase 1 do Ponto de Checagem/genética , Apoptose , Idoso , Invasividade Neoplásica , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos
7.
Artigo em Inglês | MEDLINE | ID: mdl-38517415

RESUMO

BACKGROUND: A clear classification of the subtype and grade of soft tissue sarcoma is important for predicting prognosis and establishing treatment strategies. However, the rarity and heterogeneity of these tumors often make diagnosis difficult. In addition, it remains challenging to predict the response to chemotherapy and prognosis. Thus, we need a new method to help diagnose soft tissue sarcomas and determine treatment strategies in conjunction with traditional methods. Genetic alterations can be found in some subtypes of soft tissue sarcoma, but many other types show dysregulated gene expression attributed to epigenetic changes, such as DNA methylation status. However, research on DNA methylation profiles in soft tissue sarcoma is still insufficient to provide information to assist in diagnosis and therapeutic decisions. QUESTIONS/PURPOSES: (1) Do DNA methylation profiles differ between normal tissue and soft tissue sarcoma? (2) Do DNA methylation profiles vary between different histologic subtypes of soft tissue sarcoma? (3) Do DNA methylation profiles differ based on tumor grade? METHODS: Between January 2019 and December 2022, we treated 85 patients for soft tissue sarcomas. We considered patients whose specimens were approved for pilot research by the Human Biobank of St. Vincent's Hospital, The Catholic University of Korea, as potentially eligible. Based on this, 41% (35 patients) were eligible; 1% (one patient) was excluded because of gender mismatch between clinical and genetic data after controlling for data quality. Finally, 39 specimens (34 soft tissue sarcomas and five normal samples) were included from 34 patients who had clinical data. All tissue samples were collected intraoperatively. The five normal tissue samples were from muscle tissues. There were 20 female patients and 14 male patients, with a median age of 58 years (range 19 to 82 years). Genomic DNA was extracted from frozen tissue, and DNA methylation profiles were obtained. Genomic annotation of DNA methylation sites and hierarchical cluster analysis were performed to interpret results from DNA methylation profiling. A t-test was used to analyze different methylation probes. Benjamini-Hochberg-adjusted p value calculations were used to account for bias resulting from evaluating thousands of methylation sites. RESULTS: The most common histologic subtypes were liposarcoma (n = 10) and leiomyosarcoma (n = 9). The tumor grade was Fédération Nationale des Centres de Lutte Contre Le Cancer Grades 1, 2, and 3 in 3, 15, and 16 patients, respectively. DNA methylation profiling demonstrated differences between soft tissue sarcoma and normal tissue as 21,188 cytosine-phosphate-guanine sites. Despite the small number of samples, 72 of these sites showed an adjusted p value of < 0.000001, suggesting a low probability of statistical errors. Among the 72 sites, 70 exhibited a hypermethylation pattern in soft tissue sarcoma, with only two sites showing a hypomethylation pattern. Thirty of 34 soft tissue sarcomas were distinguished from normal samples using hierarchical cluster analysis. There was a different methylation pattern between leiomyosarcoma and liposarcoma at 7445 sites. Using the data, hierarchical clustering analysis showed that liposarcoma was distinguished from leiomyosarcoma. When we used the same approach and included other subtypes with three or more samples, only leiomyosarcoma and myxofibrosarcoma were separated from the other subtypes, while liposarcoma and alveolar soft-part sarcoma were mixed with the others. When comparing DNA methylation profiles between low-grade (Grade 1) and high-grade (Grades 2 and 3) soft tissue sarcomas, a difference in methylation pattern was observed at 144 cytosine-phosphate-guanine sites. Among these, 132 cytosine-phosphate-guanine sites exhibited hypermethylation in the high-grade group compared with the low-grade group. Hierarchical clustering analysis showed a division into two groups, with most high-grade sarcomas (28 of 31) separated from the low-grade group and few (3 out of 31) clustered together with the low-grade group. However, three high-grade soft tissue sarcomas were grouped with the Grade 1 cluster, and all of these sarcomas were Grade 2. When comparing Grades 1 and 2 to Grade 3, Grade 3 tumors were separated from Grades 1 and 2. CONCLUSION: We observed a different DNA methylation pattern between soft tissue sarcomas and normal tissues. Liposarcoma was distinguished from leiomyosarcoma using methylation profiling. High-grade soft tissue sarcoma samples showed a hypermethylation pattern compared with low-grade ones. Our findings indicate the need for research using methylation profiling to better understand the diverse biological characteristics of soft tissue sarcoma. Such research should include studies with sufficient samples and a variety of subtypes, as well as analyses of the expression and function of related genes. Additionally, efforts to link this research with clinical data related to treatment and prognosis are necessary. LEVEL OF EVIDENCE: Level III, diagnostic study.

8.
Front Oncol ; 13: 1252014, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37909014

RESUMO

Radiation treatment is one of the most frequently used therapies in patients with cancer, employed in approximately half of all patients. However, the use of radiation therapy is limited by acute or chronic adverse effects and the failure to consider the tumor microenvironment. Blood vessels substantially contribute to radiation responses in both normal and tumor tissues. The present study employed a three-dimensional (3D) microvasculature-on-a-chip that mimics physiological blood vessels to determine the effect of radiation on blood vessels. This model represents radiation-induced pathophysiological effects on blood vessels in terms of cellular damage and structural and functional changes. DNA double-strand breaks (DSBs), apoptosis, and cell viability indicate cellular damage. Radiation-induced damage leads to a reduction in vascular structures, such as vascular area, branch length, branch number, junction number, and branch diameter; this phenomenon occurs in the mature vascular network and during neovascularization. Additionally, vasculature regression was demonstrated by staining the basement membrane and microfilaments. Radiation exposure could increase the blockage and permeability of the vascular network, indicating that radiation alters the function of blood vessels. Radiation suppressed blood vessel recovery and induced a loss of angiogenic ability, resulting in a network of irradiated vessels that failed to recover, deteriorating gradually. These findings demonstrate that this model is valuable for assessing radiation-induced vascular dysfunction and acute and chronic effects and can potentially improve radiotherapy efficiency.

9.
Cancers (Basel) ; 15(20)2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37894424

RESUMO

The role of upfront primary tumor resection (PTR) in patients with unresectable metastatic colorectal cancer without severe symptoms remains controversial. We retrospectively analyzed the role of PTR in overall survival (OS) in this population. Among the 205 patients who enrolled, the PTR group (n = 42) showed better performance (p = 0.061), had higher frequencies of right-sided origin (p = 0.058), the T4 stage (p = 0.003), the M1a stage (p = 0.012), and <2 organ metastases (p = 0.002), and received fewer targeted agents (p = 0.011) than the chemotherapy group (n = 163). The PTR group showed a trend for longer OS (20.5 versus 16.0 months, p = 0.064) but was not related to OS in Cox regression multivariate analysis (p = 0.220). The male sex (p = 0.061), a good performance status (p = 0.078), the T3 stage (p = 0.060), the M1a stage (p = 0.042), <2 organ metastases (p = 0.035), an RAS wild tumor (p = 0.054), and the administration of targeted agents (p = 0.037), especially bevacizumab (p = 0.067), seemed to be related to PTR benefits. Upfront PTR could be considered beneficial in some subgroups, but these findings require larger studies to verify.

10.
Cancers (Basel) ; 15(15)2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37568771

RESUMO

The clinical significance of PD-1 expression in circulating CD8+ T cells in patients with gastric cancer (GC) receiving chemotherapy remains unelucidated. Therefore, we aimed to examine its prognostic significance in blood samples of 68 patients with advanced GC who received platinum-based chemotherapy. The correlation between peripheral blood mononuclear cells, measured using fluorescence-activated cell sorting, was evaluated. Patients were divided into two groups according to the changes in PD-1+CD8+ T-cell frequencies between day 0 and 7. They were categorized as increased or decreased PD-1+CD8+ T-cell groups. The increased PD-1+CD8+ T-cell group showed longer progression-free survival (PFS) and overall survival (OS) than the decreased PD-1+CD8+ T-cell group (PFS: 8.7 months vs. 6.1 months, p = 0.007; OS: 20.7 months vs. 10.8 months, p = 0.003). The mean duration of response was significantly different between the groups (5.7 months vs. 2.5 months, p = 0.041). Multivariate analysis revealed that an increase in PD-1+CD8+ T-cell frequency was an independent prognostic factor. We concluded that the early increase in PD-1+CD8+ T-cell frequency is a potential predictor of favorable prognoses and durable responses in patients with advanced GC receiving chemotherapy.

11.
Diabetes Res Clin Pract ; 203: 110866, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37536513

RESUMO

AIMS: We aimed to evaluate the association of prediabetes, diabetes, and diabetes duration with risk of total and site-specific cancer in the Korean population aged 65 years and above. METHODS: This study included 1,232,173 subjects aged ≥ 65 years who underwent a general health screening program. Diabetes status was categorized as normal glucose tolerance, impaired fasting glucose, new-onset diabetes, diabetes duration of < 5 years, and diabetes duration of ≥ 5 years. Cox proportional hazards models were used to investigate the association of diabetes status with cancer risk. RESULTS: The risk of total cancer increased as diabetes status worsened, as did the risks of liver, biliary, and pancreatic cancer. Risks of liver, biliary, and pancreatic cancer were significantly higher in subjects aged 65-74 years than in those aged ≥ 75 years. The relationship of diabetes status with overall cancer incidence was found to significantly interact with sex. Among subjects with diabetes, the risks of liver and lung cancer were significantly higher in men than in women regardless of diabetes duration. CONCLUSIONS: Diabetes status is associated with increased risk of cancer in the elderly. There are age and sex differences in the risk of total and site-specific cancers, including liver, biliary, and pancreatic cancer. This study highlights the importance of cancer screening for elderly subjects with diabetes.

12.
Lab Chip ; 23(15): 3501-3517, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37432664

RESUMO

In vitro investigation of a glomerular filtration barrier (GFB) remains difficult because of the inability to mimic its specialized structure, although various kidney diseases are characterized by GFB dysfunction. Here, the development of a microfluidic model that replicates the physiology of the GFB has been achieved by tunable glomerular basement membrane (gBM) deposition and 3D co-culture of podocytes with glomerular endothelial cells (gECs). By precisely controlling the thickness of the gBM, our model successfully reproduced the biphasic response of the GFB, where variations in gBM thickness influence barrier properties. Moreover, this microscale proximity of gECs and podocytes facilitated their dynamic crosstalk, which is essential for maintaining the integrity and function of the GFB. We observed that addition of gBM and podocytes enhanced barrier function of gECs by inducing up-regulation of gEC's tight junctions synergistically, and moreover, found an ultrastructure of gECs-gBM-podocytes' foot process contacting each other by confocal and TEM imaging. The dynamic interaction of gECs and podocytes played a significant role in the response to drug-induced injury and the regulation of barrier properties. Nephrotoxic injury simulated in our model helped to elucidate that the over-production of vascular endothelial growth factor A from the injured podocytes mediates GFB impairment. We believe that our GFB model can provide a valuable tool for mechanistic studies such as investigating GFB biology, comprehending disease mechanisms, and evaluating potential therapeutic approaches in a controlled and physiologically relevant environment.


Assuntos
Podócitos , Podócitos/metabolismo , Barreira de Filtração Glomerular , Células Endoteliais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Membrana Basal Glomerular/metabolismo , Dispositivos Lab-On-A-Chip
13.
J Am Chem Soc ; 145(31): 17075-17086, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37490414

RESUMO

Complex I is a redox-driven proton pump that drives electron transport chains and powers oxidative phosphorylation across all domains of life. Yet, despite recently resolved structures from multiple organisms, it still remains unclear how the redox reactions in Complex I trigger proton pumping up to 200 Å away from the active site. Here, we show that the proton-coupled electron transfer reactions during quinone reduction drive long-range conformational changes of conserved loops and trans-membrane (TM) helices in the membrane domain of Complex I from Yarrowia lipolytica. We find that the conformational switching triggers a π → α transition in a TM helix (TM3ND6) and establishes a proton pathway between the quinone chamber and the antiporter-like subunits, responsible for proton pumping. Our large-scale (>20 µs) atomistic molecular dynamics (MD) simulations in combination with quantum/classical (QM/MM) free energy calculations show that the helix transition controls the barrier for proton transfer reactions by wetting transitions and electrostatic effects. The conformational switching is enabled by re-arrangements of ion pairs that propagate from the quinone binding site to the membrane domain via an extended network of conserved residues. We find that these redox-driven changes create a conserved coupling network within the Complex I superfamily, with point mutations leading to drastic activity changes and mitochondrial disorders. On a general level, our findings illustrate how catalysis controls large-scale protein conformational changes and enables ion transport across biological membranes.


Assuntos
Complexo I de Transporte de Elétrons , Prótons , Complexo I de Transporte de Elétrons/metabolismo , Oxirredução , Transporte de Elétrons , Quinonas , Bombas de Próton/metabolismo , Catálise
14.
J Gastric Cancer ; 23(2): 315-327, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37129155

RESUMO

PURPOSE: Oxaliplatin, a component of the capecitabine plus oxaliplatin (XELOX) regimen, has a more favorable toxicity profile than cisplatin in patients with advanced gastric cancer (GC). However, oxaliplatin can induce sensory neuropathy and cumulative, dose-related toxicities. Thus, the capecitabine maintenance regimen may achieve the maximum treatment effect while reducing the cumulative neurotoxicity of oxaliplatin. This study aimed to compare the survival of patients with advanced GC between capecitabine maintenance and observation after 1st line XELOX chemotherapy. MATERIALS AND METHODS: Sixty-three patients treated with six cycles of XELOX for advanced GC in six hospitals of the Catholic University of Korea were randomized 1:1 to receive capecitabine maintenance or observation. The primary endpoint was progression-free survival (PFS), analyzed using a two-sided log-rank test stratified at a 5% significance level. RESULTS: Between 2015 and 2020, 32 and 31 patients were randomized into the maintenance and observation groups, respectively. After randomization, the median number of capecitabine maintenance cycles was 6. The PFS was significantly higher in the maintenance group than the observation group (6.3 vs. 4.1 months, P=0.010). Overall survival was not significantly different between the 2 groups (18.2 vs. 16.5 months, P=0.624). Toxicities, such as hand-foot syndrome, were reported in some maintenance group patients. Maintenance treatment was a significant factor associated with PFS in multivariate analysis (hazard ratio, 0.472; 95% confidence interval, 0.250-0.890; P=0.020). CONCLUSIONS: After 6 cycles of XELOX chemotherapy, capecitabine maintenance significantly prolonged PFS compared with observation, and toxicity was manageable. Maintenance treatment was a significant prognostic factor associated with PFS. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02289547.

15.
Adv Sci (Weinh) ; 10(10): e2206872, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36725305

RESUMO

CRISPR/Cas systems offer a powerful sensing mechanism to transduce sequence-specific information into amplified analytical signals. However, performing multiplexed CRISPR/Cas assays remains challenging and often requires complex approaches for multiplexed assays. Here, a hydrogel-based CRISPR/Cas12 system termed CLAMP (Cas-Loaded Annotated Micro-Particles) is described. The approach compartmentalizes the CRISPR/Cas reaction in spatially-encoded hydrogel microparticles (HMPs). Each HMP is identifiable by its face code and becomes fluorescent when target DNA is present. The assay is further streamlined by capturing HMPs inside a microfluidic device; the captured particles are then automatically recognized by a machine-learning algorithm. The CLAMP assay is fast, highly sensitive (attomolar detection limits with preamplification), and capable of multiplexing in a single-pot assay. As a proof-of-concept clinical application, CLAMP is applied to detect nucleic acid targets of human papillomavirus in cervical brushing samples.


Assuntos
Ácidos Nucleicos , Humanos , Hidrogéis , DNA , Sistemas CRISPR-Cas/genética
16.
Anesth Pain Med (Seoul) ; 18(1): 65-69, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36746904

RESUMO

BACKGROUND: Pleurisy is an inflammation of the parietal pleura and is characterized by pleuritic pain. The most common cause of pleurisy is infection; other causes include rheumatoidarthritis, malignancy, rib fractures, or trauma. Possible causes of chest pain associated withgolf include costochondritis, stress fractures of the ribs, intercostal muscle strain, or, rarely,Tietze's syndrome and slipping rib syndrome. CASE: A 64-year-old female presented with intractable chest pain that began 4 months priorwhile playing golf. No specific cause was found after various examinations. There was persistent pain despite medical treatment. Ultrasonography (US) was performed over the painful areas, which revealed focal pleural effusions. A mixture of ropivacaine and triamcinolonewas injected into the focal pleural effusions using US guidance, which dramatically relievedher pain. CONCLUSIONS: This case demonstrates that US can be used as a diagnostic and therapeuticmodality for intractable chest pain with an undetected pathology.

18.
Front Oncol ; 12: 976450, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36505826

RESUMO

Studies have been actively conducted to identify actionable mutations and incorporate them into clinical practice in pancreatic ductal adenocarcinoma (PDAC), which is known to have a poor prognosis with traditional cytotoxic chemotherapy. A BRAF point mutation in V600E is commonly reported in KRAS wild-type PDAC, and targeting BRAF_V600E is already being applied to various carcinomas, including PDAC. Accumulated evidence also shows that not only BRAF_V600E but also short in-frame deletions of BRAF have an oncogenic function. Here, we report that a patient with BRAF N486_P490 deletion initiated on dabrafenib or trametinib, a BRAF inhibitor, and a MEK inhibitor, respectively, after cytotoxic chemotherapy failure. The patient then presented with a partial response.

19.
Biomedicines ; 10(12)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36551870

RESUMO

Patients with stage IV colorectal cancer (CRC) who have not undergone primary tumor resection (PTR) are at risk of sudden medical emergencies. Despite the ongoing controversy over the necessity and timing of PTR in patients with stage IV CRC, studies comparing the survival outcomes of elective and emergency surgery in this population are scarce. This is a retrospective study conducted at a single institute. The patients were divided into two groups: the elective surgery (ELS) group (n = 46) and the emergency surgery (EMS) group (n = 26). The primary outcome was 2-year overall survival (OS). During a median follow-up period of 27.0 months, the 2-year OS was significantly better in the ELS group (80% vs. 42.9%, p = 0.002). No significant differences were observed in the 2-year relapse-free survival and 30-day postoperative complication rates. Planning and performing elective surgery could help increase the survival rate of patients with synchronous stage IV CRC, especially those that undergo simultaneous or staged metastasectomy.

20.
Front Pharmacol ; 13: 1003849, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36324694

RESUMO

Backgrounds No standard treatment exist for reducing symptoms related to sequelae of motor vehicle accidents (MVAs). In Korea, comprehensive Korean Medicine (KM) treatment that includes botanical drugs (herbal medicine), acupuncture, pharmacopuncture, tuina, moxibustion, and cupping is covered by automobile insurance and increasingly used to help alleviate such pain. This study aimed to analyze real-world data and to evaluate the effectiveness and safety of comprehensive KM treatment for low back pain caused by MVAs. Methods We conducted a retrospective chart review of patients who received KM treatment during hospitalization. Records that lacked follow-up outcome assessments were excluded. The Verbal Numerical Rating Scale (VNRS), the Korean version of the Oswestry Disability Index (K-ODI) and the Korean version of the Roland-Morris Disability Questionnaire (K-RMDQ) were evaluated at admission and discharge. Adverse events were also analyzed. A paired t-test was used to identify the effectiveness of KM treatment. Results A total of 50 patients, 30 males and 20 females, were included in the analysis. The mean age of the patients was 40.72 ± 13.31 years and the average treatment period was 7.22 ± 3.84 days. After treatment, VNRS, K-ODI and K-RMDQ were significantly improved (p < 0.001). There was a decrease from 5.06 ± 1.60 to 3.40 ± 1.81 in VNRS, 33.38 ± 16.88 to 24.54 ± 13.63 in K-ODI, and 6.84 ± 6.27 to 4.14 ± 4.38 in K-RMDQ. During this period, a total of two adverse events were reported. Discussion Although this retrospective chart review looked into the short term effects only, comprehensive KM treatment might be an effective and safe therapeutic option to reduce acute low back pain especially after MVA. Prospective research data is needed to support this hypothesis.

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