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1.
Behav Sci (Basel) ; 13(7)2023 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-37504011

RESUMEN

Demand for foreign nurses and medical staff is rapidly increasing due to the severe labor shortage in U.S. hospitals triggered by the COVID-19 pandemic. However, empirical studies on the effect of the racial diversity of medical staff on hospital operations are still lacking. This research gap is thus investigated based on the foreign medical staff working in 3870 U.S. hospitals. Results show that workforce racial diversity has a significantly positive relationship with hospital operational efficiency regarding occupancy rate, manpower productivity, capacity productivity, and case mix index. Notably, this study empirically supports that increasing the ratio of foreign nurses positively affects the overall operational efficiency of hospitals. In addition, the study results also indicate that the hospital location, size, ownership, and teaching status act as significant control variables for the relationship between racial diversity and hospital efficiency. These results imply that hospitals with these specific operating conditions need to pay more attention to racial diversity in the workplace, as they are structurally more sensitive to the relationship between racial diversity and operational efficiency. In short, the findings of this study suggest that hospital efficiency can be operationally improved by implementing workforce ethnic diversity. For this reason, hospital stakeholders and healthcare policymakers are expected to benefit from this study's findings. Above all, the results of this study imply that if an organization adapts to extreme external environmental changes (e.g., the COVID-19 pandemic) through appropriate organizational restructuring (i.e., expanding the workforce racial diversity by hiring foreign medical staff), the organization can gain a competitive advantage, a claim that is supported by contingency theory. Further, investors are increasingly interested in ESG, especially companies that embody ethical and socially conscious workplaces, including a diverse and inclusive workforce. Thereby, seeking racial diversity in the workforce is now seen as a fundamental benchmark for organizational behavior that predicts successful ESG business practices, a claim that is supported by stakeholder theory. Therefore, in conclusion, the findings of this study suggest that workforce racial diversity is no longer an optional consideration but should be considered as one of the essential determinants of competitive advantage in organizations, particularly in the healthcare sector.

2.
Healthcare (Basel) ; 11(12)2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37372897

RESUMEN

The purpose of this study is to explore how machine learning technologies can improve healthcare operations management. A machine learning-based model to solve a specific medical problem is developed to achieve this research purpose. Specifically, this study presents an AI solution for malaria infection diagnosis by applying the CNN (convolutional neural network) algorithm. Based on malaria microscopy image data from the NIH National Library of Medicine, a total of 24,958 images were used for deep learning training, and 2600 images were selected for final testing of the proposed diagnostic architecture. The empirical results indicate that the CNN diagnostic model correctly classified most malaria-infected and non-infected cases with minimal misclassification, with performance metrics of precision (0.97), recall (0.99), and f1-score (0.98) for uninfected cells, and precision (0.99), recall (0.97), and f1-score (0.98) for parasite cells. The CNN diagnostic solution rapidly processed a large number of cases with a high reliable accuracy of 97.81%. The performance of this CNN model was further validated through the k-fold cross-validation test. These results suggest the advantage of machine learning-based diagnostic methods over conventional manual diagnostic methods in improving healthcare operational capabilities in terms of diagnostic quality, processing costs, lead time, and productivity. In addition, a machine learning diagnosis system is more likely to enhance the financial profitability of healthcare operations by reducing the risk of unnecessary medical disputes related to diagnostic errors. As an extension for future research, propositions with a research framework are presented to examine the impacts of machine learning on healthcare operations management for safety and quality of life in global communities.

3.
Sensors (Basel) ; 22(14)2022 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-35891125

RESUMEN

Urinalysis, an elementary chemical reaction-based method for analyzing color conversion factors, facilitates examination of pathological conditions in the human body. Recently, considerable urinalysis-centered research has been conducted on the analysis of urine dipstick colors using smartphone cameras; however, such methods have a drawback: the problem of reproducibility of accuracy through quantitative analysis. In this study, to solve this problem, the function values for each concentration of a range of analysis factors were implemented in an algorithm through urine dipstick RGB semi-quantitative color analysis to enable real-time results. Herein, pH, glucose, ketones, hemoglobin, bilirubin, protein (albumin), and nitrites were selected as analysis factors, and the accuracy levels of the existing equipment and the test application were compared and evaluated using artificial urine. In the semi-quantitative analysis, the red (R), green (G), and blue (B) characteristic values were analyzed by extracting the RGB characteristic values of the analysis factors for each concentration of artificial urine and obtaining linear function values. In addition, to improve the reproducibility of detection accuracy, the measurement value of the existing test equipment was set to an absolute value; using a machine-learning technique, the confusion matrix, we attempted to stabilize test results that vary with environment.


Asunto(s)
Teléfono Inteligente , Urinálisis , Glucosa , Humanos , Nitritos , Reproducibilidad de los Resultados , Urinálisis/métodos
4.
Toxicol Res ; 37(1): 25-33, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33489855

RESUMEN

Gastric cancer is the fifth leading cause of cancer and a global public health problem. 5-Fluorouracil (5-FU) is the primary drug chosen for the treatment of advanced gastric cancer, but acquired cancer drug resistance limits its effectiveness and clinical use. Proliferation assays showed that a gastric carcinoma cell line, AGS and 5-FU-resistant AGS cells (AGS FR) treated with 3-100 µM 5-FU for 48 h or 72 h showed different sensitivities to 5-FU. Immunoblot assay demonstrated that AGS FR cells expressed more COX-2 and PGE2-cognated receptor EP2 than AGS cells. AGS FR cells considerably produced PGE2 than AGS upon stimulation with 5-FU. These results suggest that COX-2 expression is associated with 5-FU resistance. Unlike AGS FR cells, AGS cells showed increased levels of both cleaved caspase-3 and Bax following 5-FU treatment. Treatment of cells with the COX-2 selective inhibitor celecoxib induced cell death of AGS FR cells in a time- and concentration-dependent manner. FACS analysis showed that celecoxib at high doses caused apoptotic cell death, demonstrating a concentration-dependent increase in the cell populations undergoing early apoptosis and late apoptosis. This apoptotic induction was strongly supported by the expression profiles of apoptosis- and survival-associated proteins in response to celecoxib; pro-apoptotic cellular proteins increased while expressions of COX-2 and p-Akt were downregulated in a concentration-dependent manner. An increase in PTEN expression was accompanied with downregulation of p-Akt. Based on the data that downregulation of COX-2 was correlated with the concentrations of celecoxib, COX-2 may play a key role in celecoxib-induced cell death of AGS FR cells. Butaprost, the EP2 agonist, promoted proliferative activity of AGS FR cells in a concentration-dependent manner compared with AGS cells. In cells exposed to butaprost, expressions of COX-2 and p-Akt were increased in a concentration-dependent manner with concomitantly reduced PTEN levels. Taken together, 5-FU-resistance in gastric cancer is correlated with COX-2 expression, and therefore the selective inhibition of COX-2 leads to suppression of cell proliferation of AGS FR cells. Modulation of COX-2 expression and its catalytic activity may be a potential therapeutic strategy to overcome 5-FU-resistant gastric cancer.

5.
Artículo en Inglés | MEDLINE | ID: mdl-35010368

RESUMEN

BACKGROUND: Mechanical tongue cleaning is an important oral hygiene procedure; it is known that a significant cause of volatile sulfur compounds (VSCs), a major component of bad breath, is due to the bacteria coating the tongue. This study was conducted to identify the effect of mechanical tongue cleaning on reducing bad breath and tongue coating. METHODS: Various mechanical tongue-cleaning methods were studied, including removing tongue coating using a toothbrush, removing tongue coating using a tongue scraper, and removing tongue coating using a toothbrush and a tongue scraper together. The results were as follows. RESULTS: First, the organic bad breath measurement value after cleaning the tongue significantly decreased in the group using only the toothbrush, the group using only the tongue scraper, and the group using both the toothbrush and the tongue scraper. However, there was no difference between the groups. Second, after cleaning the tongue, the measured values of the tongue coating in the values of WTCI (Winkel's tongue coating index) and Qray view were significantly reduced in all three groups, and there was no difference between the groups. Third, the gas measurement value in the oral cavity using a machine significantly decreased only the H2S value of the group using the tongue scraper immediately after the mechanical tongue cleaning. CONCLUSIONS: From these results, it can be confirmed that mechanical tongue cleaning is effective at reducing bad breath and tongue coating. However, in this study, there was no difference in the reduction effect according to the tools (groups) used for mechanical tongue cleaning. It can therefore be seen that wiping accurately from the rear of the tongue to the front is more effective at reducing bad breath and tongue coating.


Asunto(s)
Halitosis , Pruebas Diagnósticas de Rutina , Halitosis/prevención & control , Humanos , Compuestos de Azufre , Lengua , Cepillado Dental
6.
Anal Chem ; 92(17): 11654-11663, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32786492

RESUMEN

Enzyme-linked immunosorbent assays (ELISA) for the detection of soluble epoxide hydrolase (sEH), a key enzyme in the metabolism of fatty acids and a biomarker, may increasingly represent an important diagnostic tool. However, there is a lack of ELISAs for mouse sEH quantification, thus resulting in a bottleneck in understanding the pathogenesis of many diseases related to sEH based on mouse models. In this work, nanobodies recognizing mouse sEH were obtained through rebiopanning against mouse sEH in the previous phage display library of human sEH. Later, we developed four ELISAs involving a combination of anti-mouse sEH polyclonal antibodies (pAbs) and nanobodies. It was found that the double antibodies worked as dual filters and had a huge impact on both the sensitivity and selectivity of sandwich immunoassays. The switch from anti-human sEH pAbs to anti-mouse sEH pAbs led to over a 100-fold increase in the sensitivity and a dramatic decrease of the limit of detection to a picogram per milliliter range in format B (pAb/biotin-VHH/streptavidin-poly-horseradish peroxidase). Moreover, we found that the four sandwich ELISAs might demonstrate excellent selectivities to mouse sEH, despite the antibodies alone showing significant cross-reactivity to the matrix, indicating the enhanced selectivity of double antibodies as dual filters. Eventually, for the first time, the ELISA (format B) was successfully used to measure the mouse sEH level in cancer cells with ultralow abundances. The ELISAs proposed here represent a sensitive tool for tracking sEH in various biological processes and also provide deep insights into developing sandwich immunoassays against various targets in terms of both the sensitivity and selectivity.


Asunto(s)
Ensayo de Inmunoadsorción Enzimática/métodos , Epóxido Hidrolasas/metabolismo , Inmunoensayo/métodos , Anticuerpos de Dominio Único/metabolismo , Animales , Humanos , Ratones
7.
J Anal Sci Technol ; 11(1): 21, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32542115

RESUMEN

Cubic-shaped Ag3PO4 crystals with a mean size of 1 µm were synthesized by a precipitation method from a mixed solution of AgNO3, Na2HPO4, and triethanolamine. The antibacterial activities against Escherichia coli, Listeria innocua, and Pseudomonas syringae DC3000 in both the absence and presence of Ag3PO4 under dark conditions and in the presence of Ag3PO4 under red-light (625 nm) and blue-light (460 nm) irradiation were examined. The concentrations of reactive oxygen species (ROS) were also measured in the antibacterial action of the Ag3PO4 against Escherichia coli. The photoinduced enhancement of the Ag3PO4 antibacterial activity under blue-light irradiation is explained by the formation of ROS during the antibacterial action of the Ag3PO4. Moreover, the antiviral activity of Ag3PO4 against amphotropic 10A1 murine leukemia virus enhanced under blue-light irradiation via ROS production. These results provide an insight into extended bio-applications of Ag3PO4.

8.
Phytomedicine ; 52: 60-69, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30599913

RESUMEN

BACKGROUND: Licochalconce (LC) H is an artificial compound in the course of synthesizing LCC in 2013. So far, few studies on the effects of LCH have been found in the literature. Despite progress in treatment modalities for oral cancer, the cure from cancer has still limitations. PURPOSE: The effects of LCH were investigated on human oral squamous cell carcinoma (OSCC) cells to elucidate its mechanisms. STUDY DESIGN: We explored the mechanism of action of LCH by which it could have effects on JAK2/STAT3 signaling pathway. METHODS: To confirm LCH anti-cancer effect, analyzed were MTT assay, DAPI staining, soft agar, kinase assay, molecular docking simulation, flow cytometry and Western blotting analysis. RESULTS: According to docking and molecular dynamics simulations, the predicted pose of the complex LCH and JAK2 seems reasonable and LCH is strongly bound to active JAK2 with opened activation loop. The LCH inhibitor is surrounded by specific ATP-binding pocket in which it is stabilized by forming hydrogen bonds and hydrophobic interactions. It is shown that LCH plays as a competitive inhibitor in an active state of JAK2. LCH caused a dose-dependent decrease in phosphorylation of JAK2 and STAT3. More interestingly, LCH suppressed JAK2 kinase activity in vitro by its direct binding to the JAK2. LCH significantly inhibited the JAK2/STAT3 signaling pathway, causing the down-regulation of target genes such as Bcl-2, survivin, cyclin D1, p21 and p27. In addition, LCH inhibited cell proliferation and colony formation of OSCC cells in a dose- and time-dependent manner, as well as induction of cell apoptosis through extrinsic and intrinsic pathway. The induction of apoptosis in OSCC cells by LCH was evident in the increased production of ROS, loss of mitochondrial membrane potential, release of cyto c, variation of apoptotic proteins and activation of caspase cascade. CONCLUSION: LCH not only induces apoptosis in OSCC cells through the JAK/STAT3 signaling pathway but also inhibits cell growth. It is proposed that LCH has a promising use for the chemotherapeutic agent of oral cancer.


Asunto(s)
Apoptosis/efectos de los fármacos , Carcinoma de Células Escamosas/patología , Chalconas/farmacología , Janus Quinasa 2/metabolismo , Neoplasias de la Boca/patología , Carcinoma de Células Escamosas/tratamiento farmacológico , Caspasas/metabolismo , Ciclo Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Chalconas/química , Ciclina D1/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Simulación del Acoplamiento Molecular , Neoplasias de la Boca/tratamiento farmacológico , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/efectos de los fármacos , Survivin/metabolismo
9.
J Cell Physiol ; 234(2): 1780-1793, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30070696

RESUMEN

Licochalcone (LC) families have been reported to have a wide range of biological function such as antioxidant, antibacterial, antiviral, and anticancer effects. Although various beneficial effects of LCD were revealed, its anticancer effect in human oral squamous cancer has not been identified. To examine the signaling pathway of LCD's anticancer effect, we determined whether LCD has physical interaction with Janus kinase (JAK2)/signal transducer and activator of transcription-3 (STAT3) signaling, which is critical in promoting cancer cell survival and proliferation. Our results demonstrated that LCD inhibited the kinase activity of JAK2, soft agar colony formation, and the proliferation of HN22 and HSC4 cells. LCD also induced mitochondrial apoptotic events such as altered mitochondrial membrane potential and reactive oxygen species production. LCD increased the expression of apoptosis-associated proteins in oral squamous cell carcinoma (OSCC) cells. Finally, the xenograft study showed that LCD significantly inhibited HN22 tumor growth. Immunohistochemical data supported that LCD suppressed p-JAK2 and p-STAT3 expression and induced cleaved-caspase-3 expression. These results indicate that the anticancer effect of LCD is due to the direct targeting of JAK2 kinase. Therefore, LCD can be used for therapeutic application against OSCC.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Chalconas/farmacología , Janus Quinasa 2/antagonistas & inhibidores , Inhibidores de las Cinasas Janus/farmacología , Neoplasias de la Boca/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Janus Quinasa 2/metabolismo , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/patología , Terapia Molecular Dirigida , Neoplasias de la Boca/enzimología , Neoplasias de la Boca/patología , Transducción de Señal , Carcinoma de Células Escamosas de Cabeza y Cuello/enzimología , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
10.
Molecules ; 23(12)2018 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-30501110

RESUMEN

Protein kinases are deeply involved in immune-related diseases and various cancers. They are a potential target for structure-based drug discovery, since the general structure and characteristics of kinase domains are relatively well-known. However, the ATP binding sites in protein kinases, which serve as target sites, are highly conserved, and thus it is difficult to develop selective kinase inhibitors. To resolve this problem, we performed molecular dynamics simulations on 26 kinases in the aqueous solution, and analyzed topological water networks (TWNs) in their ATP binding sites. Repositioning of a known kinase inhibitor in the ATP binding sites of kinases that exhibited a TWN similar to interleukin-1 receptor-associated kinase 4 (IRAK4) allowed us to identify a hit molecule. Another hit molecule was obtained from a commercial chemical library using pharmacophore-based virtual screening and molecular docking approaches. Pharmacophoric features of the hit molecules were hybridized to design a novel compound that inhibited IRAK4 at low nanomolar levels in the in vitro assay.


Asunto(s)
Diseño de Fármacos , Quinasas Asociadas a Receptores de Interleucina-1/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Agua/química , Sitios de Unión , Evaluación Preclínica de Medicamentos , Reposicionamiento de Medicamentos , Simulación del Acoplamiento Molecular , Inhibidores de Proteínas Quinasas/química , Estaurosporina/química , Estaurosporina/farmacología
11.
J Cell Biochem ; 119(12): 10118-10130, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30129052

RESUMEN

Oral cancer is of an aggressive malignancy that arises on oral cavity and lip, 90% of cancers histologically originated in the squamous cells. Licochalcone (LC)C has been known as natural phenolic chalconoid substances, and its origin is the root of Glycyrrhiza glabra or Glycyrrhiza inflata. LCC inhibited oral squamous cell carcinoma (OSCC) cell viability, mitochondrial function, and anchorage-independent growth in a dose-dependent manner. To investigate the ability of LCC to target Janus kinase 2 (JAK2), we performed pull-down binding assay, kinase assay, and docking simulation. The molecular docking studies were performed between JAK2 and the potent inhibitor LCC. It was shown that LCC tightly interacted with ATP-binding site of JAK2. In addition, LCC inhibited the JAK2/signal transducer and activator of transcription 3 pathway, upregulated p21, and downregulated Bcl-2, Mcl-1, and Survivin, while it disrupted mitochondrial membrane potential and subsequently caused cytochrome c release with activation of multi-caspase, eventually leading to apoptosis in HN22 and HSC4 cells. LCC elevated the protein levels of Bax, cleaved Bid and PARP, and increased Apaf-1, and this effect was reversed by LCC treatment. Our results demonstrated that treatment of OSCC cells with LCC induced the death receptor (DR)4 and DR5 expression level with the generation of reactive oxygen species and the upregulation of CHOP protein expression. Taken together, these results could provide the basis for clinical application as a new therapeutic strategy in the treatment of oral cancer.


Asunto(s)
Carcinoma de Células Escamosas/tratamiento farmacológico , Chalconas/farmacología , Janus Quinasa 2/genética , Neoplasias de la Boca/tratamiento farmacológico , Factor de Transcripción STAT3/genética , Apoptosis/efectos de los fármacos , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Simulación del Acoplamiento Molecular , Neoplasias de la Boca/genética , Neoplasias de la Boca/patología , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos
12.
BMB Rep ; 51(5): 219-224, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29636122

RESUMEN

Necroptosis is an emerging form of programmed cell death occurring via active and well-regulated necrosis, distinct from apoptosis morphologically, and biochemically. Necroptosis is mainly unmasked when apoptosis is compromised in response to tumor necrosis factor alpha. Unlike apoptotic cells, which are cleared by macrophages or neighboring cells, necrotic cells release danger signals, triggering inflammation, and exacerbating tissue damage. Evidence increasingly suggests that programmed necrosis is not only associated with pathophysiology of disease, but also induces innate immune response to viral infection. Therefore, necroptotic cell death plays both physiological and pathological roles. Physiologically, necroptosis induce an innate immune response as well as premature assembly of viral particles in cells infected with virus that abrogates host apoptotic machinery. On the other hand, necroptosis per se is detrimental, causing various diseases such as sepsis, neurodegenerative diseases and ischemic reperfusion injury. This review discusses the signaling pathways leading to necroptosis, associated necroptotic proteins with target-specific inhibitors and diseases involved. Several studies currently focus on protective approaches to inhibiting necroptotic cell death. In cancer biology, however, anticancer drug resistance severely hampers the efficacy of chemotherapy based on apoptosis. Pharmacological switch of cell death finds therapeutic application in drug- resistant cancers. Therefore, the possible clinical role of necroptosis in cancer control will be discussed in brief. [BMB Reports 2018; 51(5): 219-224].


Asunto(s)
Apoptosis , Enfermedad , Animales , Humanos , Modelos Biológicos , Necrosis , Transducción de Señal
13.
Int J Oncol ; 52(5): 1749-1759, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29568920

RESUMEN

The anti-inflammatory effects of oridonin (Ordn) have been well established in previous studies. However, the apoptotic effects of Ordn on oral cancer cells have not yet been evaluated, at least to the best of our knowledge. The aim of this study was to examine the apoptotic activity of Ordn in oral squamous cell carcinoma cells and to eluciudate the underlying mechanisms. For this purpose, we employed experimental techniques, such as MTT assay, DAPI staining, soft agar assay, flow cytometry and western blot analysis. Our results revealed that Ordn suppressed oral cancer cell proliferation and soft agar colony formation, while it induced reactive oxygen species (ROS)-dependent apoptosis in a dose or time-dependent manner. The generation of ROS was detected in HN22 and HSC4 cells treated with Ordn and the use of the free radical scavenger, N-acetyl-L-cysteine, almost blocked Ordn-induced apoptosis. The phosphorylation of JNK and p38 mitogen-activated protein kinase (MAPK) was manifested in the Ordn-treated cells. Furthermore, Ordn induced the apoptosis of oral cancer cells through the mitochondrial-dependent pathway, involving the loss of mitochondrial membrane potential, the release of cytochrome c, the induction of poly(ADP-Ribose) polymerase (PARP) cleavage, alterations in the ratios of apoptotic proteins and the activation of the caspase cascade. Taken together, these findings indicate that Ordn induces the apoptosis of oral cancer cells probably via ROS-mediated JNK/p38 MAPK and mitochondrial pathways; thus, Ordn may have potential for use in the treatment of oral cancer.

14.
Oncol Lett ; 14(2): 1207-1214, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28789335

RESUMEN

Programmed necrosis, or necroptosis, is a type of specialized cell death with necrotic characteristics, including the loss of membrane integrity and swollen organelles in dying cells. However, unlike simple necrosis, it may be induced as an alternative form of cell death when apoptosis is blocked and it is mediated in an orchestrated manner, similar to apoptosis, by a series of signaling molecules. Necroptosis-associated proteins and their specific small molecules have been extensively identified in order to illuminate the underlying mechanisms by which necroptosis is activated through a novel signaling pathway. However, the biological significance of necroptosis, which is known as a secondary route of apoptosis, remains under debate. Concurrent with these concerns, the clinical application of necroptosis has been cautiously proposed to treat necroptosis-associated diseases, and to overcome resistance to anticancer drugs. Accordingly, the present review will highlight the harnessing of necroptosis for anticancer therapy. To this end, the state-of-the art technique of necroptosis as a cancer therapy will be briefly described, and then its potential for clinical purposes will be delineated. For a further understanding of necroptosis, the present review begins with a basic introduction to necroptosis and its multifaceted physiological consequences.

15.
Immune Netw ; 17(3): 171-178, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28680378

RESUMEN

11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1) catalyzes the conversion of inactive cortisone into active cortisol, which has pleiotropic roles in various biological conditions, such as immunological and metabolic homeostasis. Cortisol is mainly produced in the adrenal gland, but can be locally regenerated in the liver, fat, and muscle. Its diverse actions are primarily mediated by binding to the glucocorticoid receptor. SW982, a human synovial cell line, expresses 11ß-HSD type 1, but not type 2, that catalyzes the conversion of cortisone to cortisol. In this study, therefore, we investigated the control of lipopolysaccharide (LPS)-induced inflammatory responses by prereceptor regulation-mediated maintenance of cortisol levels. Preliminarily, cell seeding density and incubation period were optimized for analyzing the catalytic activity of SW982. Additionally, cellular 11ß-HSD1 still remained active irrespective of monolayer or spheroid culture conditions. Inflammatory stimulants, such as interleukin (IL)-1ß, tumor necrosis factor (TNF)α, and LPS, did not affect the catalytic activity of 11ß-HSD1, although a high dose of LPS significantly decreased its activity. Additionally, autocrine effects of cortisol on inflammatory responses were investigated in LPS-stimulated SW982 cells. LPS upregulated pro-inflammatory cytokines, including IL-6 and IL-1ß, in SW982 cells, while cortisol production, catalyzed by cellular 11ß-HSD1, downregulated LPS-stimulated cytokines. Furthermore, suppression of NFκB activation-mediated pro-inflammatory responses by cortisol was revealed. In conclusion, the activity of cellular 11ß-HSD1 was closely correlated with suppression of LPS-induced inflammation. Therefore, these results partly support the notion that prereceptor regulation of locally regenerated cortisol could be taken into consideration for treatment of inflammation-associated diseases, including arthritis.

16.
Asian-Australas J Anim Sci ; 29(8): 1197-206, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27165017

RESUMEN

Adipose tissue in the loin muscle area of beef cattle as a marbling factor is directly associated with beef quality. To elucidate whether properties of proteins involved in depot specific adipose tissue were sex-dependent, we analyzed protein expression of intramuscular adipose tissue (IMAT) and omental adipose tissue (OMAT) from Hanwoo cows, steers, and bulls of Korean native beef cattle by liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomic analysis, quantitative polymerase chain reaction (PCR) and western blot analysis. Two different adipose depots (i.e. intramuscular and omental) were collected from cows (n = 7), steers (n = 7), or bulls (n = 7). LC-MS/MS revealed a total of 55 and 35 proteins in IMAT and OMAT, respectively. Of the 55 proteins identified, 44, 40, and 42 proteins were confirmed to be differentially expressed in IMAT of cows, steers, and bulls, respectively. In OMAT of cows, steers, and bulls, 33, 33, and 22 were confirmed to be differentially expressed, respectively. Tropomyosin (TPM) 1, TPM 2, and TPM3 were subjected to verification by quantitative PCR and western blot analysis in IMAT and OMAT of Hanwoo cows, steers, and bulls as key factors closely associated with muscle development. Both mRNA levels and protein levels of TPM1, TPM2, and TPM3 in IMAT were lower in bulls compared to in cows or steers suggesting that they were positively correlated with marbling score and quality grade. Our results may aid the regulation of marbling development and improvement of meat quality grades in beef cattle.

17.
Asian-Australas J Anim Sci ; 29(11): 1653-1663, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27165031

RESUMEN

Meat quality is a complex trait influenced by many factors, including genetics, nutrition, feeding environment, animal handling, and their interactions. To elucidate relevant factors affecting pork quality associated with oxidative stress and muscle development, we analyzed protein expression in high quality longissimus dorsi muscles (HQLD) and low quality longissimus dorsi muscles (LQLD) from Duroc pigs by liquid chromatographytandem mass spectrometry (LC-MS/MS)-based proteomic analysis. Between HQLD (n = 20) and LQLD (n = 20) Duroc pigs, 24 differentially expressed proteins were identified by LC-MS/MS. A total of 10 and 14 proteins were highly expressed in HQLD and LQLD, respectively. The 24 proteins have putative functions in the following seven categories: catalytic activity (31%), ATPase activity (19%), oxidoreductase activity (13%), cytoskeletal protein binding (13%), actin binding (12%), calcium ion binding (6%), and structural constituent of muscle (6%). Silver-stained image analysis revealed significant differential expression of lactate dehydrogenase A (LDHA) between HQLD and LQLD Duroc pigs. LDHA was subjected to in vitro study of myogenesis under oxidative stress conditions and LDH activity assay to verification its role in oxidative stress. No significant difference of mRNA expression level of LDHA was found between normal and oxidative stress condition. However, LDH activity was significantly higher under oxidative stress condition than at normal condition using in vitro model of myogenesis. The highly expressed LDHA was positively correlated with LQLD. Moreover, LDHA activity increased by oxidative stress was reduced by antioxidant resveratrol. This paper emphasizes the importance of differential expression patterns of proteins and their interaction for the development of meat quality traits. Our proteome data provides valuable information on important factors which might aid in the regulation of muscle development and the improvement of meat quality in longissimus dorsi muscles of Duroc pigs under oxidative stress conditions.

18.
Oncol Rep ; 36(1): 117-24, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27176604

RESUMEN

Manumycin A (Manu A) is a natural product isolated from Streptomyces parvulus and has been reported to have anti-carcinogenic and anti-biotic properties. However, neither its molecular mechanism nor its molecular targets are well understood. Thus, the aim of the present study was to explore the possibility that Manu A has cancer preventive and chemotherapeutic effects on malignant pleural mesothelioma (MPM) through regulation of Sp1 and induction of mitochondrial cell death pathway. Manu A inhibited the cell viability of MSTO-211H and H28 cells in a concentration­dependent manner as determined by MTS assay. IC50 values were calculated as 8.3 and 4.3 µM in the MSTO-311H and H28 cells following 48 h incubation, respectively. Manu A induced a significant increase in apoptotic indices as shown by DAPI staining, Annexin V assay, multi-caspase activity and mitochondrial membrane potential assay. The downregulation of Sp1 mRNA and protein expression by Manu A led to apoptosis by suppressing Sp1-regulated proteins (cyclin D1, Mcl-1 and survivin). Manu A decreased the protein levels of BID, Bcl-xL and PARP while it increased Bax levels. Manu A caused depolarization of the mitochondrial membrane with induction of CHOP, DR4 and DR5. Our results demonstrated that Manu A exerted anticancer effects by inducing apoptosis via inhibition of the Sp1-related signaling pathway in human MPM.


Asunto(s)
Apoptosis/efectos de los fármacos , Neoplasias Pulmonares/tratamiento farmacológico , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mesotelioma/tratamiento farmacológico , Neoplasias Pleurales/tratamiento farmacológico , Polienos/farmacología , Alcamidas Poliinsaturadas/farmacología , Factor de Transcripción Sp1/metabolismo , Anexina A5/metabolismo , Proteína Proapoptótica que Interacciona Mediante Dominios BH3/metabolismo , Línea Celular Tumoral , Permeabilidad de la Membrana Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ciclina D1/antagonistas & inhibidores , Humanos , Proteínas Inhibidoras de la Apoptosis/antagonistas & inhibidores , Mesotelioma Maligno , Mitocondrias/metabolismo , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/antagonistas & inhibidores , Poli(ADP-Ribosa) Polimerasas/metabolismo , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Survivin , Factor de Transcripción CHOP/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Proteína bcl-X/metabolismo
19.
Int J Oncol ; 48(4): 1749-57, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26847145

RESUMEN

Licochalcone B (Lico B), which belongs to the retrochalcone family, is isolated from the roots of Chinese licorice. Lico B has been reported to have several other useful pharmacological properties, such as anti-inflammatory, antibacterial, antioxidant, antiulcer, anticancer, and anti-metastasis activities. We elucidated the underlying mechanism by which Lico B can induce apoptosis in oral squamous cell carcinoma (OSCC). Our results showed that exposure of OSCC cells (HN22 and HSC4) to Lico B significantly inhibited cell proliferation in a time- and concentration-dependent manner. Lico B caused cell cycle arrest at G1 phase along with downregulation of cyclin D1 and upregulation of p21 and p27 proteins. Lico B also facilitated the diffusion of phospholipid phosphatidylserine (PS) from inner to outer leaflets of the plasma membrane with chromatin condensation, DNA fragmentation, accumulated sub-G1 population in a concentration-dependent manner. Moreover, Lico B promoted the generation of reactive oxygen species (ROS), which, in turn, can induce CHOP, death receptor (DR) 4 and DR5. Lico B treatment induced downregulation of anti-apoptotic proteins (Bid and Bcl-xl and Mcl-1), and up-regulation of pro-apoptotic protein (Bax). Lico B also led to the loss of mitochondrial membrane potential (MMP), resulting in cytochrome c release. As can be expected from the above results, the apoptotic protease activating factor-1 (Apaf-1) and survivin were oppositely expressed in favor of apoptotic cell death. This notion was supported by the fact that Lico B activated multi-caspases with cleavage of poly (ADP-ribose) polymerase (PARP) protein. Therefore, it is suggested that Lico B is a promising drug for the treatment of human oral cancer via the induction of apoptotic cell death.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Carcinoma de Células Escamosas/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Chalconas/farmacología , Neoplasias de la Boca/metabolismo , Fosfatidilserinas/metabolismo , Apoptosis , Carcinoma de Células Escamosas/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Neoplasias de la Boca/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos
20.
Mol Cells ; 39(3): 195-203, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26743904

RESUMEN

Copper is an essential element required for a variety of functions exerted by cuproproteins. An alteration of the copper level is associated with multiple pathological conditions including chronic ischemia, atherosclerosis and cancers. Therefore, copper homeostasis, maintained by a combination of two copper ions (Cu(+) and Cu(2+)), is critical for health. However, less is known about which of the two copper ions is more toxic or functional in endothelial cells. Cubic-shaped Cu2O and CuO crystals were prepared to test the role of the two different ions, Cu(+) and Cu(2+), respectively. The Cu2O crystal was found to have an effect on cell death in endothelial cells whereas CuO had no effect. The Cu2O crystals appeared to induce p62 degradation, LC3 processing and an elevation of LC3 puncta, important processes for autophagy, but had no effect on apoptosis and necrosis. Cu2O crystals promote endothelial cell death via autophagy, elevate the level of reactive oxygen species such as superoxide and nitric oxide, and subsequently activate AMP-activated protein kinase (AMPK) through superoxide rather than nitric oxide. Consistently, the AMPK inhibitor Compound C was found to inhibit Cu2O-induced AMPK activation, p62 degradation, and LC3 processing. This study provides insight on the pathophysiologic function of Cu(+) ions in the vascular system, where Cu(+) induces autophagy while Cu(2+) has no detected effect.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Autofagia , Cobre/farmacología , Superóxidos/metabolismo , Animales , Bovinos , Células Cultivadas , Células Endoteliales , Regulación de la Expresión Génica/efectos de los fármacos , Pirazoles/metabolismo , Pirimidinas/metabolismo
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