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2.
Ann Surg Oncol ; 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38695982

RESUMEN

BACKGROUND: Despite stage IV categorization, survival outcomes for breast cancer patients who experience contralateral axillary lymph node metastasis (CAM) remain uncertain. This study aimed to investigate the clinical outcomes for patients with metachronous CAM to provide insights into its prognosis and treatment recommendations. METHODS: This study retrospectively reviewed medical records of patients who underwent curative surgery for breast cancer and experienced CAM as the first site of distant metastasis (DM) during the follow-up period between January 2001 and April 2023. Survival outcomes of the CAM patients were compared with those of breast cancer patients with other DM via propensity score-matching (PSM). RESULTS: The study identified 40 breast cancer patients with metachronous CAM. The estimated 5-year overall survival (OS) was 39.6%, and the progression-free survival was 39.4%. The patients with CAM exhibited marginally better OS than the patients with DM (p = 0.071), but survival similar to that of the patients with isolated supraclavicular node recurrence (SCN) (p = 0.509). Moreover, matching of CAM with DM using two PSM models showed a consistently insignificant survival difference (hazard ratio [HR], 1.47; p = 0.124 vs. HR, 1.19; p = 0.542). Ipsilateral breast tumor recurrences (IBTRs) were experienced by 12 patients before or concurrently with the CAM. These patients exhibited significantly better survival than the remaining patients (HR, 0.28; p = 0.024). CONCLUSION: The breast cancer patients with CAM showed survival similar to that for the patients with DM, supporting the current stage IV classification of the CAM. However, CAM associated with IBTR exhibited superior survival outcomes, suggesting that this subset of CAM may benefit from treatments with curative intent.

3.
J Am Chem Soc ; 146(18): 12645-12655, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38651821

RESUMEN

The increased production of plastics is leading to the accumulation of plastic waste and depletion of limited fossil fuel resources. In this context, we report a strategy to create polymers that can undergo controlled depolymerization by linking renewable feedstocks with siloxane bonds. α,ω-Diesters and α,ω-diols containing siloxane bonds were synthesized from an alkenoic ester derived from castor oil and then polymerized with varied monomers, including related biobased monomers. In addition, cyclic monomers derived from this alkenoic ester and hydrosiloxanes were prepared and cyclized to form a 26-membered macrolactone containing a siloxane unit. Sequential ring-opening polymerization of this macrolactone and lactide afforded an ABA triblock copolymer. This set of polymers containing siloxanes underwent programmed depolymerization into monomers in protic solvents or with hexamethyldisiloxane and an acid catalyst. Monomers afforded by the depolymerization of polyesters containing siloxane linkages were repolymerized to demonstrate circularity in select polymers. Evaluation of the environmental stability of these polymers toward enzymatic degradation showed that they undergo enzymatic hydrolysis by a fungal cutinase from Fusarium solani. Evaluation of soil microbial metabolism of monomers selectively labeled with 13C revealed differential metabolism of the main chain and side chain organic groups by soil microbes.


Asunto(s)
Fusarium , Polimerizacion , Siloxanos , Siloxanos/química , Aceites de Plantas/química , Polímeros/química , Estructura Molecular , Hidrolasas de Éster Carboxílico
4.
J Breast Cancer ; 27(1): 1-13, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38433090

RESUMEN

PURPOSE: In total mastectomy (TM), sentinel lymph node biopsy (SLNB) is recommended but can be omitted for breast-conserving surgery (BCS) in patients with ductal carcinoma in situ (DCIS). However, concerns regarding SLNB-related complications and their impact on quality of life exist. Consequently, further research is required to evaluate the role of axillary surgeries, including SLNB, in the treatment of TM. We aimed to explore the clinicopathological factors and outcomes associated with axillary surgery in patients with a final diagnosis of pure DCIS who underwent BCS or TM. METHODS: We retrospectively analyzed large-scale data from the Korean Breast Cancer Society registration database, highlighting on patients diagnosed with pure DCIS who underwent surgery and were categorized into two groups: BCS and TM. Patients were further categorized into surgery and non-surgery groups according to their axillary surgery status. The analysis compared clinicopathological factors and outcomes according to axillary surgery status between the BCS and TM groups. RESULTS: Among 18,196 patients who underwent surgery for DCIS between 1981 and 2022, 11,872 underwent BCS and 6,324 underwent TM. Both groups leaned towards axillary surgery more frequently for large tumors. In the BCS group, clinical lymph node status was associated with axillary surgery (odds ratio, 11.101; p = 0.003). However, in the TM group, no significant differences in these factors were observed. Survival rates did not vary between groups according to axillary surgery performance. CONCLUSION: The decision to perform axillary surgery in patients with a final diagnosis of pure DCIS does not affect the prognosis, regardless of the breast surgical method. Furthermore, regardless of the breast surgical method, axillary surgery, including SLNB, should be considered for high-risk patients, such as those with large tumors. This may reduce unnecessary axillary surgery and enhance the patients' quality of life.

5.
Ann Surg Oncol ; 31(5): 3168-3176, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38368292

RESUMEN

OBJECTIVE: This study aimed to determine whether sentinel lymph node biopsy (SLNB) alone could afford oncological outcomes comparable with axillary lymph node dissection (ALND) in patients with early breast cancer without palpable lymphadenopathy who underwent total mastectomy (TM) and were SLN-positive. METHODS: This study analyzed clinical data of 6747 patients with breast cancer who underwent TM between 2014 and 2018 in two tertiary hospitals in Korea. Overall, 643 clinical stage T1-3 N0 patients who did not receive neoadjuvant therapy and had one to two metastatic SLNs at the time of surgery were included. Propensity score matching was performed between the SLNB alone and ALND groups, adjusting for clinical T stage and number of metastatic SLNs. In total, 237 patients were allocated to each group. RESULTS: Mean number of metastatic SLNs was 1.2 for the SLNB group and 1.6 for the ALND group. With a median follow-up of 65.0 months, 5 year disease-free survival was 90.8% for the SLNB group and 93.9% for the ALND group (hazard ratio [HR] 1.35, 95% confidence interval [CI] 0.70-2.58; p = 0.36). 5 year ipsilateral locoregional recurrence-free survival (LRRFS) was not significantly different between the two groups (95.1% and 98.3% for the SLNB and ALND groups, respectively) [HR 1.86, 95% CI 0.69-5.04; p = 0.21]. In the SLNB group, patients who received radiation therapy (RT) showed superior 5 year LRRFS than patients who did not receive RT (100% vs. 92.9%; p = 0.02). CONCLUSION: Collectively, our findings suggest that SLNB could afford comparable outcomes to ALND in patients with early breast cancer and one to two metastatic SLNs who underwent TM. Importantly, RT could decrease locoregional recurrence in patients who underwent SLNB alone.


Asunto(s)
Neoplasias de la Mama , Linfadenopatía , Ganglio Linfático Centinela , Humanos , Femenino , Neoplasias de la Mama/patología , Mastectomía Simple , Mastectomía , Recurrencia Local de Neoplasia/patología , Escisión del Ganglio Linfático , Biopsia del Ganglio Linfático Centinela , Ganglios Linfáticos/patología , Linfadenopatía/cirugía , Axila/patología , Ganglio Linfático Centinela/cirugía , Ganglio Linfático Centinela/patología
6.
Breast Cancer Res ; 26(1): 14, 2024 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-38254240

RESUMEN

BACKGROUND: This study aimed to investigate the contralateral breast cancer (CBC) recurrence rate in Korean breast cancer patients according to their BRCA1/2 germline mutation status, focusing particularly on the CBC recurrence risk in BRCA1/2 negative (BRCAx) patients. METHODS: We conducted a retrospective study on 13,107 primary breast cancer patients. The patients were divided into high-risk and low-risk groups for hereditary breast cancer based on the Korean National Health Insurance Service's eligibility criteria for BRCA1/2 germline mutation testing. The high-risk group was further categorized into the BRCA mutation group, the BRCAx group, and the not tested group. We evaluated the overall survival and cumulative risk of developing CBC in these patients. RESULTS: Among 4494 high-risk patients, 973 (21.7%) underwent genetic testing for BRCA1/2 germline mutation, revealing mutations in 158 patients (16.2%). We observed significant overall survival differences across all four groups, with the high-risk, not-tested group demonstrating notably worse overall survival (p < 0.001). However, when adjusted for other prognostic factors, there was no significant differences in hazard ratio of death between the four groups. The cumulative risk of CBC also varied among the groups. Patients with BRCA1/2 mutations showed a 7.3-fold increased risk of CBC compared to the low-risk group (95% CI 4.11-13.0, p < 0.001). Interestingly, BRCAx patients also demonstrated a significantly higher risk of CBC (HR 2.77, 95% CI 1.76-4.35, p < 0.001). The prognostic importance of the BRCAx for CBC recurrence persisted after adjusting for the age and subtype, but became insignificant when the family history of breast cancer was adjusted. CONCLUSION: Breast cancer patients who are at high risk of hereditary breast cancer but with wild-type BRCA 1/2 genes (BRCAx) have increased risk of developing contralateral breast cancer when compared to the low-risk patients. More careful surveillance and follow-up can be offered to these patients especially when they have family history of breast cancer.


Asunto(s)
Proteína BRCA1 , Neoplasias de la Mama , Humanos , Femenino , Proteína BRCA1/genética , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/genética , Estudios Retrospectivos , Proteína BRCA2/genética , República de Corea/epidemiología
7.
ACS Appl Bio Mater ; 6(5): 1981-1991, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-37083357

RESUMEN

Numerous disinfection methods have been developed to reduce the transmission of infectious diseases that threaten human health. However, it still remains elusively challenging to develop eco-friendly and cost-effective methods that deactivate a wide range of pathogens, from viruses to bacteria and fungi, without doing any harm to humans or the environment. Herein we report a natural spraying protocol, based on a water-dispersible supramolecular sol of nature-derived tannic acid (TA) and Fe3+, which is easy-to-use and low-cost. Our formulation effectively deactivates viruses (influenza A viruses, SARS-CoV-2, and human rhinovirus) as well as suppressing the growth and spread of pathogenic bacteria (Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, and Acinetobacter baumannii) and fungi (Pleurotus ostreatus and Trichophyton rubrum). Its versatile applicability in a real-life setting is also demonstrated against microorganisms present on the surfaces of common household items (e.g., air filter membranes, disposable face masks, kitchen sinks, mobile phones, refrigerators, and toilet seats).


Asunto(s)
Antiinfecciosos , COVID-19 , Virus , Humanos , Polifenoles/farmacología , SARS-CoV-2 , COVID-19/prevención & control , Antiinfecciosos/farmacología , Desinfección/métodos , Bacterias , Escherichia coli , Hongos
8.
Polymers (Basel) ; 15(5)2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36904345

RESUMEN

One-step fabrication method for thin films and shells is developed with nature-derived eggshell membrane hydrolysates (ESMHs) and coffee melanoidins (CMs) that have been discarded as food waste. The nature-derived polymeric materials, ESMHs and CMs, prove highly biocompatible with living cells, and the one-step method enables cytocompatible construction of cell-in-shell nanobiohybrid structures. Nanometric ESMH-CM shells are formed on individual probiotic Lactobacillus acidophilus, without any noticeable decrease in viability, and the ESMH-CM shells effectively protected L. acidophilus in the simulated gastric fluid (SGF). The cytoprotection power is further enhanced by Fe3+-mediated shell augmentation. For example, after 2 h of incubation in SGF, the viability of native L. acidophilus is 30%, whereas nanoencapsulated L. acidophilus, armed with the Fe3+-fortified ESMH-CM shells, show 79% in viability. The simple, time-efficient, and easy-to-process method developed in this work would contribute to many technological developments, including microbial biotherapeutics, as well as waste upcycling.

9.
Stem Cell Res ; 66: 102986, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36493708

RESUMEN

CRISPR/Cas9-based transcriptional regulation systems can induce the site-specific activation or repression of endogenous genes. p300 is a transcriptional co-activator that functions as a histone acetyltransferase that regulates gene transcription via chromatin remodeling. Here, we generated a human embryonic stem cell line stably expressing catalytically dead Cas9 (dCas9) fused to the catalytic core domain of human p300 via lentiviral transduction. This cell line can be used for locus-specific histone acetylation in combination with guide RNAs, and is a valuable tool for gene regulation in stem cell research.


Asunto(s)
Proteína 9 Asociada a CRISPR , Células Madre Embrionarias Humanas , Humanos , Proteína 9 Asociada a CRISPR/genética , Sistemas CRISPR-Cas/genética , Regulación de la Expresión Génica , Factores de Transcripción/genética , Línea Celular , Activación Transcripcional
10.
Cancer Res Treat ; 55(2): 562-569, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36164944

RESUMEN

PURPOSE: In sentinel lymph node (SLN) biopsy (SLNB) during breast cancer surgery, SLN mapping using dye and isotope (DUAL) may have lower false-negative rates than the dye-only (DYE) method. However, the long-term outcomes of either method are unclear. We aimed to compare long-term oncological outcomes of DYE and DUAL for SLNB in early breast cancer. Materials and Methods: This retrospective single-institution cohort study included 5,795 patients (DYE, 2,323; DUAL, 3,472) with clinically node-negative breast cancer who underwent SLNB and no neoadjuvant therapy. Indigo carmine was used for the dye method and Tc99m-antimony trisulfate for the isotope. To compare long-term outcomes, pathologic N0 patients were selected from both groups, and propensity score matching (PSM), considering age, pT category, breast surgery, and adjuvant treatment, was performed (1,441 patients in each group). RESULTS: The median follow-up duration was 8.7 years. The median number of harvested sentinel nodes was 3.21 and 3.12 in the DYE and DUAL groups, respectively (p=0.112). The lymph node-positive rate was not significantly different between the two groups in subgroups of similar tumor sizes (p > 0.05). Multivariate logistic regression revealed that the mapping method was not significantly associated with the lymph node-positive rate (p=0.758). After PSM, the 5-year axillary recurrence rate (DYE 0.8% vs. DUAL 0.6%, p=0.096), and 5-year disease-free survival (DYE 93.9% vs. DUAL 93.7%, p=0.402) were similar between the two groups. CONCLUSION: Dye alone for SLNB was not inferior to dual mapping regarding long-term oncological outcomes in early breast cancer.


Asunto(s)
Neoplasias de la Mama , Ganglio Linfático Centinela , Humanos , Femenino , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/cirugía , Neoplasias de la Mama/patología , Ganglio Linfático Centinela/diagnóstico por imagen , Ganglio Linfático Centinela/cirugía , Ganglio Linfático Centinela/patología , Estudios Retrospectivos , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/cirugía , Ganglios Linfáticos/patología , Estudios de Cohortes , Puntaje de Propensión , Biopsia del Ganglio Linfático Centinela/métodos , Radioisótopos
11.
Biomaterials ; 286: 121575, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35598335

RESUMEN

Human in vitro hepatic models that faithfully recapitulate liver function are essential for successful basic and translational research. A limitation of current in vitro models, which are extensively used for drug discovery and toxicity testing, is the loss of drug metabolic function due to the low expression and activity of cytochrome P450 (CYP450) enzymes. Here, we aimed to generate human pluripotent stem cell-derived hepatic organoids (hHOs) with a high drug metabolic ability. We established a two-step protocol to produce hHOs from human pluripotent stem cells for long-term expansion and drug testing. Fully differentiated hHOs had multicellular composition and exhibited cellular polarity and hepatobiliary structures. They also displayed remarkable CYP450 activity and recapitulated the metabolic clearance, CYP450-mediated drug toxicity, and metabolism. Furthermore, hHOs successfully modeled Wilson's disease in terms of Cu metabolism, drug responses, and diagnostic marker expression and secretion. In conclusion, hHOs exhibit high capacity for drug testing and disease modeling. Hence, this hepatic model system provides an advanced tool for studying hepatic drug metabolism and diseases.


Asunto(s)
Células Madre Pluripotentes Inducidas , Células Madre Pluripotentes , Diferenciación Celular , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Hígado/metabolismo , Modelos Biológicos , Organoides/metabolismo
12.
Molecules ; 26(19)2021 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-34641624

RESUMEN

(‒)-Cannabidiol (CBD) is one of the major phytocannabinoids extracted from the Cannabis genus. Its non-psychoactiveness and therapeutic potential, partly along with some anecdotal-if not scientific or clinical-evidence on the prevention and treatment of neurological diseases, have led researchers to investigate the biochemical actions of CBD on neural cells. This review summarizes the previously reported mechanistic studies of the CBD actions on primary neural cells at the in vitro cell-culture level. The neural cells are classified into neurons, microglia, astrocytes, oligodendrocytes, and neural stem cells, and the CBD effects on each cell type are described. After brief introduction on CBD and in vitro studies of CBD actions on neural cells, the neuroprotective capability of CBD on primary neurons with the suggested operating actions is discussed, followed by the reported CBD actions on glia and the CBD-induced regeneration from neural stem cells. A summary section gives a general overview of the biochemical actions of CBD on neural cells, with a future perspective. This review will provide a basic and fundamental, but crucial, insight on the mechanistic understanding of CBD actions on neural cells in the brain, at the molecular level, and the therapeutic potential of CBD in the prevention and treatment of neurological diseases, although to date, there seem to have been relatively limited research activities and reports on the cell culture-level, in vitro studies of CBD effects on primary neural cells.


Asunto(s)
Cannabidiol/farmacología , Células-Madre Neurales/citología , Neuroglía/citología , Neuronas/citología , Animales , Cannabidiol/química , Células Cultivadas , Humanos , Estructura Molecular , Células-Madre Neurales/efectos de los fármacos , Neuroglía/efectos de los fármacos , Neuronas/efectos de los fármacos , Cultivo Primario de Células
13.
Surg Infect (Larchmt) ; 22(7): 741-751, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33533687

RESUMEN

Background: Treatment of biliary infection in liver transplant (LT) recipients is a challenge, especially because of ineffectiveness of the antibiotic agents otherwise recommended for non-transplant populations. We aimed to understand the factors underlying the choice of antibiotic therapy. Patients and Methods: A total of 373 bile cultures from LT recipients with biliary complications (n = 127; LT group) and from a non-transplant population that underwent cholecystectomy for acute cholecystitis (n = 246; non-transplant group) between January 2009 and December 2018, were investigated. Results: Polymicrobial cultures (13.4% vs. 1.6%; p < 0.001), Enterococcus faecium (26.0% vs. 8.5%; p < 0.001), and Pseudomonas (13.4% vs. 4.1%; p = 0.001) in the LT group, and non-faecium enterococci (3.9% vs. 18.3%; p < 0.001) and Enterobacteriales (40.2% vs. 54.9%; p = 0.007), especially Escherichia (11.0% vs. 29.7%; p < 0.001), in the non-transplant group, showed higher abundance. Most of the antibiotic agents recommended as initial antibiotic therapy for the non-transplant population as per previous guidelines were not effective in LT recipients. The incidences of Enterococcus faecium (14.9% vs. 32.5%; p = 0.029) in the LT recipients with model for end-stage liver disease (MELD) score >12 and non-faecium enterococci (8.5% vs. 1.3%; p = 0.042) in those with MELD score ≤12 were higher than those in the other group. The incidence of Enterobacteriales increased over time after LT (p = 0.048) and was similar to that in the non-transplant group after one year of LT. Bile micro-organisms in LT recipients, resistant to most antibiotic agents, especially soon after LT changed over time and became similar to those in the non-transplant group after one year of LT. Conclusions: Antibiotic therapy for biliary infection in LT recipients should be different from that in non-transplant populations, considering clinical factors such as the time interval after LT and MELD score.


Asunto(s)
Enfermedad Hepática en Estado Terminal , Trasplante de Hígado , Antibacterianos/uso terapéutico , Bilis , Enfermedad Hepática en Estado Terminal/tratamiento farmacológico , Humanos , Índice de Severidad de la Enfermedad
14.
Phys Chem Chem Phys ; 22(32): 17867-17879, 2020 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-32766621

RESUMEN

Steady-state and transient absorption spectra with <50 fs time resolution were obtained for two conjugated polymers, both with ≈200 conjugated double bonds (N), constrained in planar, stable, polyene frameworks. Solutions of the polymers exhibit the same S2 → S1 → S* → S0 decay pathway observed for the N = 11-19 polyene oligomers and for zeaxanthin homologues with N = 11-23. Comparisons with the excited state dynamics of polydiactylene and a much longer, more disordered polyene polymer (poly(DEDPM)) show that the S2, S1, and S* lifetimes of the four polymers are almost identical. The S* signals in the polymers are assigned to absorption from vibrationally excited ground states. In spite of significant heterogeneities and variations in conjugation lengths in these long polyenes, their S0 → S2 absorptions are vibronically-resolved in room temperature solutions with electronic origins at ≈600 nm. The limiting wavelength for the S0 → S2 transitions is consistent with the persistence of bond length alternation in the electronic ground states and a HOMO-LUMO band gap in polyenes with N ≈ 200. The coincidence of the well-resolved S0 → S2 electronic origins and the convergence of the excited state lifetimes in the four polymers point to a common, "nearly infinite" polyene limit.

15.
Adv Biosyst ; 4(8): e2000092, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32500640

RESUMEN

Nanotopography mimicking extracellular environments reportedly impact cell morphological changes; however, elucidating this relationship has been challenging. To control cellular responses using nanostructures, in this study, the quantitative relationship between nanotopography and cell spreading mediated by focal adhesions (FAs) is demonstrated using adipose-derived stem cells (ASCs). The spreading of ASCs and area of FAs are analyzed for the distribution of filamentous actin and vinculin, respectively, using fluorescent images. FAs require a specific area for adhesion (herein defined as effective contact area [ECA]) to maintain cell attachment on nanopillar arrays. An ECA is the area of FAs supported by nanopillars, multiplying the area fraction (AF) of their top surface. Regarding the spreading of cells, the mean area of ASCs linearly decreases as the mean area of FAs increases. Because the area of FAs is inversely correlated to the AF of the nanopillar arrays, the spreading of cells can be quantitatively correlated with nanotopography. The results provide a conceptual framework for controlling cell behaviors to design artificial substrates for tissue-engineering applications.


Asunto(s)
Adipocitos/citología , Fluorocarburos/farmacología , Adhesiones Focales/efectos de los fármacos , Silanos/farmacocinética , Células Madre/citología , Adipocitos/efectos de los fármacos , Adipocitos/fisiología , Tejido Adiposo/citología , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/fisiología , Adhesión Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Ácidos Grasos , Adhesiones Focales/ultraestructura , Humanos , Nanoestructuras/química , Nanoestructuras/ultraestructura , Células Madre/efectos de los fármacos , Células Madre/fisiología , Ingeniería de Tejidos/métodos
16.
Biomed Mater ; 15(5): 055026, 2020 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-32526712

RESUMEN

Nanoparticle-enhanced coatings of bone implants are a promising method to facilitate sustainable wound healing, leading to an increase in patient well-being. This article describes the in vitro characterization of osteoblast cells interacting with polyelectrolyte multilayers, which contain detonation nanodiamonds (NDs), as a novel class of carbon-based coating material, which presents a unique combination of photoluminescence and drug-binding properties. The cationic polyelectrolyte, namely polydiallyldimethylammonium chloride (PDDA), has been used to immobilize NDs on silica glass. The height of ND-PDDA multilayers varies from a minimum of 10 nm for one bilayer to a maximum of 90 nm for five bilayers of NDs and PDDA. Human fetal osteoblasts (hFOBs) cultured on ND-PDDA multilayers show a large number of focal adhesions, which were studied via quantitative fluorescence imaging analysis. The influence of the surface roughness on the filopodia formation was assessed via scanning electron microscopy and atomic force microscopy. The nano-rough surface of five bilayers constrained the filopodia formation. The hFOBs grown on NDs tend to show not only a similar cell morphology compared to cells cultured on extracellular matrix protein-coated silica glass substrates, but also increased cell viability by about 40%. The high biocompatibility of the ND-PDDA multilayers, indicated via high cell proliferation and sound cell adhesion, shows their potential for biomedical applications such as drug-eluting coatings and biomaterials in general.


Asunto(s)
Sustitutos de Huesos , Nanodiamantes , Osteoblastos/efectos de los fármacos , Materiales Biocompatibles , Adhesión Celular , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Electrólitos , Humanos , Técnicas In Vitro , Membrana Dobles de Lípidos/química , Luminiscencia , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Nanotecnología/métodos , Polielectrolitos , Polietilenos/química , Compuestos de Amonio Cuaternario/química , Dióxido de Silicio/química , Propiedades de Superficie , Cicatrización de Heridas
17.
FASEB J ; 34(7): 9141-9155, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32421247

RESUMEN

Human-induced pluripotent stem cells (hiPSCs) are invaluable sources for drug screening and toxicity tests because of their differentiation potential and proliferative capacity. Recently, the CRISPR-Cas9-mediated homologous recombination system has enabled reporter knock-ins at desired loci in hiPSCs, and here, we generated a hiPSC reporter line expressing mCherry-tagged cytochrome P450 1A1 (CYP1A1), which can be utilized to screen for the modulators of aryl hydrocarbon receptor (AHR) in live cells. CYP1A1-mCherry hiPSCs exhibited typical characteristics of pluripotent stem cells such as marker expression, differentiation potential, and normal karyotype. After differentiation into hepatocyte-like cells (HLCs), CYP1A1-mCherry fusion protein was expressed and localized at the endoplasmic reticulum, and induced by AHR agonists. We obtained 23 hits modulating CYP1A1 expression from high-content screening with 241 hepatotoxicity chemicals and nuclear receptor ligands, and identified three upregulating chemicals and two downregulating compounds. Responses of hiPSC-HLCs against an AHR agonist were more similar to human primary hepatocytes than of HepG2 hepatocellular carcinoma cells. This platform has the advantages of live-cell screening without sacrificing cells (unlike previously available CYP1A1 reporter cell lines), as well as an indefinite supply of cells, and can be utilized in a wide range of screening related to AHR- and CYP1A1-associated diseases in desired cell types.


Asunto(s)
Citocromo P-450 CYP1A1/química , Fluorescencia , Hepatocitos/citología , Células Madre Pluripotentes Inducidas/citología , Preparaciones Farmacéuticas/metabolismo , Bibliotecas de Moléculas Pequeñas/farmacología , Diferenciación Celular , Citocromo P-450 CYP1A1/metabolismo , Células Hep G2 , Hepatocitos/efectos de los fármacos , Ensayos Analíticos de Alto Rendimiento , Humanos , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células Madre Pluripotentes Inducidas/enzimología , Transducción de Señal
18.
Sci Rep ; 10(1): 5586, 2020 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-32221392

RESUMEN

The first member of the velvet family of proteins, VeA, regulates sexual development and secondary metabolism in the filamentous fungus Aspergillus nidulans. In our study, through comparative proteome analysis using wild type and veA-deletion strains, new putative regulators of sexual development were identified and functionally analyzed. Among these, SvfA, containing a yeast survival factor 1 domain, plays multiple roles in the growth and differentiation of A. nidulans. Deletion of the svfA gene resulted in increased sensitivity to oxidative and cold stress as in yeast. The svfA-deletion strain showed an increase in bi-polar germination and a decrease in radial growth rate. The deletion strain formed structurally abnormal conidiophores and thus produced lower amounts of conidiospores during asexual development. The svfA-deletion strain produced few Hülle cells and small cleistothecia with no ascospores, indicating the requirement of svfA for the completion of sexual development. Transcription and genetic analyses indicated that SvfA modulates the expression of key development regulatory genes. Western blot analysis revealed two forms of SvfA. The larger form showed sexual-specific and VeA-dependent production. Also, the deletion of svfA caused decreased ST (sterigmatocystin) production. We propose that SvfA is a novel central regulator of growth, differentiation and secondary metabolism in A. nidulans.


Asunto(s)
Aspergillus nidulans/crecimiento & desarrollo , Proteínas Fúngicas/fisiología , Aspergillus nidulans/genética , Western Blotting , Regulación Fúngica de la Expresión Génica/genética , Reproducción , Esporas Fúngicas/crecimiento & desarrollo
19.
Appl Microsc ; 50(1): 26, 2020 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-33580331

RESUMEN

The biocompatible polyurethane acrylate (PUA) nanopillars were fabricated by soft lithography using three different sizes of nanobeads (350, 500, and 1000 nm), and the human adipose-derived stem cells (hASCs) were cultured on the nanopillars. The hASCs and their various behaviors, such as cytoplasmic projections, migration, and morphology, were observed by high resolution images using a scanning electron microscope (SEM). With the accurate analysis by SEM for the controlled sizes of nanopillars, the deflections are observed at pillars fabricated with 350- and 500-nm nanobeads. These high-resolution images could offer crucial information to elucidate the complicated correlations between nanopillars and the cells, such as morphology and cytoplasmic projections.

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