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1.
Can J Anaesth ; 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671251

RESUMEN

PURPOSE: Remimazolam is a recently developed ultra-short-acting benzodiazepine used for anesthesia induction and maintenance. Nevertheless, the effective bolus dose of remimazolam for i-gel® (Intersurgical Ltd., Wokingham, Berkshire, UK) insertion without the use of neuromuscular blocking agents (NMBAs) has not been well established. METHODS: This study included 25 adult patients scheduled for surgery under general anesthesia who were eligible for i-gel use. Anesthesia was induced with predetermined bolus doses of remimazolam, starting at 0.3 mg·kg-1 for the first patient, without the use of NMBAs. All patients concurrently received remifentanil using target-controlled infusion (TCI) at a fixed effect-site concentration (Ce) of 3.0 ng·mL-1. Insertion of the i-gel was attempted 90 sec after remimazolam administration, and insertion conditions were assessed. Subsequent doses of remimazolam were decreased or increased by 0.05 mg·kg-1, depending on the success or failure of i-gel insertion. RESULTS: The mean (standard deviation) 50% effective dose (ED50) of a remimazolam bolus for successful i-gel insertion as determined by the modified Dixon's up-and-down method was 0.100 (0.027) mg·kg-1. The ED50 and ED95 estimated by isotonic regression were 0.111 (83% confidence interval [CI], 0.096 to 0.131) mg·kg-1 and 0.182 (95% CI, 0.144 to 0.195) mg·kg-1, respectively. None of the patients required treatment for hypotension or bradycardia during anesthesia induction. CONCLUSION: Based on the ED95 of remimazolam bolus dose determined in our study, we recommend using 0.182 mg·kg-1 of remimazolam in combination with remifentanil TCI at a Ce of 3.0 ng·mL-1 for successful i-gel insertion without NMBAs in adult patients. This regimen seems effective with a low risk of hemodynamic instability during anesthesia induction. STUDY REGISTRATION: ClinicalTrials.gov ( NCT05298228 ); first submitted 6 March 2022.


RéSUMé: OBJECTIF: Le remimazolam est une benzodiazépine à action ultra-courte récemment mise au point et utilisée pour l'induction et le maintien de l'anesthésie. Toutefois, la dose efficace en bolus de remimazolam pour l'insertion de l'i-gel® (Intersurgical Ltd., Wokingham, Berkshire, Royaume-Uni) sans utiliser de bloqueurs neuromusculaires (BNM) n'a pas été bien établie. MéTHODE: Cette étude a inclus 25 adultes devant bénéficier d'une intervention chirurgicale sous anesthésie générale qui étaient éligibles à l'utilisation d'un i-gel. L'anesthésie a été induite avec des doses prédéterminées en bolus de remimazolam, à partir de 0,3 mg·kg−1 pour la première personne, sans utiliser de BNM. Toutes les personnes anesthésiées ont reçu en parallèle du rémifentanil en perfusion à objectif de concentration à une concentration au site effecteur (Ce) de 3,0 ng·mL−1. L'insertion de l'i-gel a été tentée 90 secondes après l'administration de remimazolam, et les conditions d'insertion ont été évaluées. Les doses subséquentes de remimazolam ont été diminuées ou augmentées de 0,05 mg·kg−1, en fonction du succès ou de l'échec de l'insertion de l'i-gel. RéSULTATS: La dose efficace moyenne (écart type) de 50 % (DE50) d'un bolus de remimazolam pour une insertion réussie de l'i-gel, telle que déterminée par la méthode « up-and-down ¼ de Dixon modifiée, était de 0,100 (0,027) mg·kg−1. Les DE50 et DE95 estimées par régression isotonique étaient de 0,111 (intervalle de confiance [IC] à 83 %, 0,096 à 0,131) mg·kg−1 et 0,182 (IC 95 %, 0,144 à 0,195) mg·kg−1, respectivement. Aucun·e patient·e n'a eu besoin de traitement pour une hypotension ou une bradycardie pendant l'induction de l'anesthésie. CONCLUSION: D'après la DE95 de la dose de remimazolam en bolus déterminée dans notre étude, nous recommandons d'utiliser 0,182 mg·kg−1 de remimazolam en association avec une perfusion à objectif de concentration de rémifentanil à une Ce de 3,0 ng·mL−1 pour réussir l'insertion de l'i-gel sans BNM chez la patientèle adulte. Ce schéma semble efficace avec un faible risque d'instabilité hémodynamique lors de l'induction de l'anesthésie. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT05298228); première soumission le 6 mars 2022.

2.
Math Biosci Eng ; 21(3): 3876-3909, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38549312

RESUMEN

Bortezomib and oncolytic virotherapy are two emerging targeted cancer therapies. Bortezomib, a proteasome inhibitor, disrupts protein degradation in cells, leading to the accumulation of unfolded proteins that induce apoptosis. On the other hand, virotherapy uses genetically modified oncolytic viruses (OVs) to infect cancer cells, trigger cell lysis, and activate anti-tumor response. Despite progress in cancer treatment, identifying administration protocols for therapeutic agents remains a significant concern, aiming to strike a balance between efficacy, minimizing toxicity, and administrative costs. In this work, optimal control theory was employed to design a cost-effective and efficient co-administration protocols for bortezomib and OVs that could significantly diminish the population of cancer cells via the cell death program with the NF$ \kappa $B-BAX-RIP1 signaling network. Both linear and quadratic control strategies were explored to obtain practical treatment approaches by adapting necroptosis protocols to efficient cell death programs. Our findings demonstrated that a combination therapy commencing with the administration of OVs followed by bortezomib infusions yields an effective tumor-killing outcome. These results could provide valuable guidance for the development of clinical administration protocols in cancer treatment.


Asunto(s)
Neoplasias , Viroterapia Oncolítica , Virus Oncolíticos , Humanos , Bortezomib/farmacología , Bortezomib/uso terapéutico , Viroterapia Oncolítica/métodos , Virus Oncolíticos/fisiología , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Muerte Celular
3.
J Math Biol ; 86(1): 14, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36512100

RESUMEN

Cellular senescence can induce dual effects (promotion or inhibition) on cancer progression. While immune cells naturally respond and migrate toward various chemotactic sources from the tumor mass, various factors including senescent tumor cells (STCs) in the tumor microenvironment may affect this chemotactic movement. In this work, we investigate the mutual interactions between the tumor cells and the immune cells that either inhibit or facilitate tumor growth by developing a mathematical model that consists of taxis-reaction-diffusion equations and receptor kinetics for the key players in the interaction network. We apply a mathematical model to a transwell Boyden chamber invasion assay used in the experiments to illustrate that STCs can play a pivotal role in negating immune attack through tight regulation of intra- and extra-cellular signaling molecules. In particular, we show that senescent tumor cells in cell cycle arrest can block intratumoral infiltration of CD8+ T cells by secreting a high level of CXCL12, which leads to significant reduction its receptors, CXCR4, on T cells, and thus impaired chemotaxis. The predictions of nonlinear responses to CXCL12 were in good agreement with experimental data. We tested several hypotheses on immune-tumor interactions under various biochemical conditions in the tumor microenvironment and developed new concepts for anti-tumor strategies targeting senescence induced immune impairment.


Asunto(s)
Citocinas , Neoplasias , Humanos , Quimiotaxis/fisiología , Microambiente Tumoral , Modelos Teóricos , Línea Celular Tumoral
4.
R Soc Open Sci ; 9(2): 210705, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35127110

RESUMEN

In a tumour microenvironment, tumour-associated neutrophils could display two opposing differential phenotypes: anti-tumour (N1) and pro-tumour (N2) effector cells. Converting N2 to N1 neutrophils provides innovative therapies for cancer treatment. In this study, a mathematical model for N1-N2 dynamics describing the cancer survival and immune inhibition in response to TGF-ß and IFN-ß is considered. The effects of exogenous intervention of TGF-ß inhibitor and IFN-ß are examined in order to enhance N1 recruitment to combat tumour progression. Our approach employs optimal control theory to determine drug infusion protocols that could minimize tumour volume with least administration cost possible. Four optimal control scenarios corresponding to different therapeutic strategies are explored, namely, TGF-ß inhibitor control only, IFN-ß control only, concomitant TGF-ß inhibitor and IFN-ß controls, and alternating TGF-ß inhibitor and IFN-ß controls. For each scheme, different initial conditions are varied to depict different pathophysiological condition of a cancer patient, leading to adaptive treatment schedule. TGF-ß inhibitor and IFN-ß drug dosages, total drug amount, infusion times and relative cost of drug administrations are obtained under various circumstances. The control strategies achieved could guide in designing individualized therapeutic protocols.

5.
PLoS Comput Biol ; 17(10): e1009457, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34669701

RESUMEN

Acute administration of trastuzumab (TZB) may induce various forms of cognitive impairment. These cancer-related cognitive changes (CRCC) are regulated by an adverse biological process involving cancer stem cells (CSCs) and IL-6. Recent studies have reported that atorvastatin (ATV) may change the dynamic of cognitive impairment in a combination (TZB+ATV) therapy. In this study, we investigate the mutual interactions between cancer stem cells and the tumor cells that facilitate cognitive impairment during long term TZB therapy by developing a mathematical model that involves IL-6 and the key apoptotic regulation. These include the densities of tumor cells and CSCs, and the concentrations of intracellular signaling molecules (NFκB, Bcl-2, BAX). We apply the mathematical model to a single or combination (ATV+TZB) therapy used in the experiments to demonstrate that the CSCs can enhance CRCC by secreting IL-6 and ATV may interfere the whole regulation. We show that the model can both reproduce the major experimental observation on onset and prevention of CRCC, and suggest several important predictions to guide future experiments with the goal of the development of new anti-tumor and anti-CRCC strategies. Moreover, using this model, we investigate the fundamental mechanism of onset of cognitive impairment in TZB-treated patients and the impact of alternating therapies on the anti-tumor efficacy and intracellular response to different treatment schedules.


Asunto(s)
Antineoplásicos/efectos adversos , Atorvastatina/farmacología , Disfunción Cognitiva/inducido químicamente , Modelos Biológicos , Trastuzumab/efectos adversos , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Proliferación Celular/efectos de los fármacos , Biología Computacional , Citocinas/metabolismo , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/fisiopatología , Células Madre Neoplásicas/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Trastuzumab/uso terapéutico , Células Tumorales Cultivadas
6.
R Soc Open Sci ; 8(9): 210594, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34631119

RESUMEN

In various diseases, the STAT family display various cellular controls over various challenges faced by the immune system and cell death programs. In this study, we investigate how an intracellular signalling network (STAT1, STAT3, Bcl-2 and BAX) regulates important cellular states, either anti-apoptosis or apoptosis of cancer cells. We adapt a mathematical framework to illustrate how the signalling network can generate a bi-stability condition so that it will induce either apoptosis or anti-apoptosis status of tumour cells. Then, we use this model to develop several anti-tumour strategies including IFN-ß infusion. The roles of JAK-STATs signalling in regulation of the cell death program in cancer cells and tumour growth are poorly understood. The mathematical model unveils the structure and functions of the intracellular signalling and cellular outcomes of the anti-tumour drugs in the presence of IFN-ß and JAK stimuli. We identify the best injection order of IFN-ß and DDP among many possible combinations, which may suggest better infusion strategies of multiple anti-cancer agents at clinics. We finally use an optimal control theory in order to maximize anti-tumour efficacy and minimize administrative costs. In particular, we minimize tumour volume and maximize the apoptotic potential by minimizing the Bcl-2 concentration and maximizing the BAX level while minimizing total injection amount of both IFN-ß and JAK2 inhibitors (DDP).

7.
PLoS Comput Biol ; 17(2): e1008257, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33596197

RESUMEN

Lung cancer is one of the leading causes of cancer-related deaths worldwide and is characterized by hijacking immune system for active growth and aggressive metastasis. Neutrophils, which in their original form should establish immune activities to the tumor as a first line of defense, are undermined by tumor cells to promote tumor invasion in several ways. In this study, we investigate the mutual interactions between the tumor cells and the neutrophils that facilitate tumor invasion by developing a mathematical model that involves taxis-reaction-diffusion equations for the critical components in the interaction. These include the densities of tumor and neutrophils, and the concentrations of signaling molecules and structure such as neutrophil extracellular traps (NETs). We apply the mathematical model to a Boyden invasion assay used in the experiments to demonstrate that the tumor-associated neutrophils can enhance tumor cell invasion by secreting the neutrophil elastase. We show that the model can both reproduce the major experimental observation on NET-mediated cancer invasion and make several important predictions to guide future experiments with the goal of the development of new anti-tumor strategies. Moreover, using this model, we investigate the fundamental mechanism of NET-mediated invasion of cancer cells and the impact of internal and external heterogeneity on the migration patterning of tumour cells and their response to different treatment schedules.


Asunto(s)
Trampas Extracelulares/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Modelos Biológicos , Biología Computacional , Simulación por Computador , Humanos , Técnicas In Vitro , Interleucina-8/antagonistas & inhibidores , Neoplasias Pulmonares/terapia , Invasividad Neoplásica/patología , Metástasis de la Neoplasia/patología , Neutrófilos/metabolismo , Neutrófilos/patología , Receptores de Factores de Crecimiento Transformadores beta/antagonistas & inhibidores , Transducción de Señal , Factor de Crecimiento Transformador beta/antagonistas & inhibidores , Microambiente Tumoral
8.
J R Soc Interface ; 18(174): 20200669, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33402021

RESUMEN

Proteasome inhibition and oncolytic virotherapy are two emerging targeted cancer therapies. Bortezomib, a proteasome inhibitor, disrupts the degradation of proteins in the cell leading to accumulation of unfolded proteins inducing apoptosis. On the other hand, oncolytic virotherapy uses genetically modified oncolytic viruses (OV) to infect cancer cells, induce cell lysis, and activate an antitumour response. In this work, optimal control theory is used to minimize the cancer cell population by identifying strategic infusion protocols of bortezomib, OV and natural killer (NK) cells. Three different therapeutic protocols are explored: (i) periodic bortezomib and single administrations of both OV and NK cells therapy; (ii) alternating sequential combination therapy; and (iii) NK cell depletion and infusion therapy. In the first treatment scheme, early OV administration followed by well-timed adjuvant NK cell infusion maximizes antitumour efficacy. The second strategy supports timely OV infusion. The last treatment scheme indicates that transient NK cell depletion followed by appropriate NK cell adjuvant therapy yields the maximal benefits. Relative doses and administrative costs of the three anticancer agents for each approach are qualitatively presented. This study provides potential polytherapeutic strategies in cancer treatment.


Asunto(s)
Antineoplásicos , Neoplasias , Viroterapia Oncolítica , Virus Oncolíticos , Bortezomib/farmacología , Bortezomib/uso terapéutico , Humanos , Células Asesinas Naturales , Neoplasias/tratamiento farmacológico
9.
J Appl Stat ; 48(4): 738-749, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35706984

RESUMEN

Bivariate recurrent event data are observed when subjects are at risk of experiencing two different type of recurrent events. In this paper, our interest is to suggest statistical model when there is a substantial portion of subjects not experiencing recurrent events but having a terminal event. In a context of recurrent event data, zero events can be related with either the risk free group or a terminal event. For simultaneously reflecting both a zero inflation and a terminal event in a context of bivariate recurrent event data, a joint model is implemented with bivariate frailty effects. Simulation studies are performed to evaluate the suggested models. Infection data from AML (acute myeloid leukemia) patients are analyzed as an application.

10.
Philos Trans R Soc Lond B Biol Sci ; 375(1807): 20190390, 2020 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-32713306

RESUMEN

Glioblastoma multiforme (GBM) is the most aggressive form of brain cancer with a short median survival time. GBM is characterized by the hallmarks of aggressive proliferation and cellular infiltration of normal brain tissue. miR-451 and its downstream molecules are known to play a pivotal role in regulation of the balance of proliferation and aggressive invasion in response to metabolic stress in the tumour microenvironment (TME). Surgery-induced transition in reactive astrocyte populations can play a significant role in tumour dynamics. In this work, we develop a multi-scale mathematical model of miR-451-LKB1-AMPK-OCT1-mTOR pathway signalling and individual cell dynamics of the tumour and reactive astrocytes after surgery. We show how the effects of fluctuating glucose on tumour cells need to be reprogrammed by taking into account the recent history of glucose variations and an AMPK/miR-451 reciprocal feedback loop. The model shows how variations in glucose availability significantly affect the activity of signalling molecules and, in turn, lead to critical cell migration. The model also predicts that microsurgery of a primary tumour induces phenotypical changes in reactive astrocytes and stem cell-like astrocytes promoting tumour cell proliferation and migration by Cxcl5. Finally, we investigated a new anti-tumour strategy by Cxcl5-targeting drugs. This article is part of the theme issue 'Multi-scale analysis and modelling of collective migration in biological systems'.


Asunto(s)
Proliferación Celular , Glioblastoma/fisiopatología , Invasividad Neoplásica/fisiopatología , Factor 1 de Transcripción de Unión a Octámeros/genética , Transducción de Señal , Astrocitos/patología , Glioblastoma/cirugía , Glucosa/metabolismo , Humanos , Modelos Biológicos , Factor 1 de Transcripción de Unión a Octámeros/metabolismo
11.
Materials (Basel) ; 13(13)2020 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-32610504

RESUMEN

Feasibility studies have been performed on ingots with reduced hot-top heights for the cost-effective hot forging of heavy ingots. The quality of the heavy ingots is generally affected by internal voids, which have been known to be accompanied by inclusions and segregation. To guarantee the expected mechanical performance of the forged products, these voids should be closed and eliminated during the hot open die forging process. Hence, to effectively control the internal voids, the optimum hot-top height and forging schedules need to be determined. In order to improve the utilization ratio of ingots, the ingot hot-top height needs to be minimized. To investigate the effect of the reduced hot-top height on the forged products, shaft and bar products have been manufactured via hot forging of ingots having various hot-top heights. From the operational results, the present work suggests effective forging processes to produce acceptable shaft and bar products using ingots having reduced hot tops. The mechanical properties of shop-floor products manufactured from ingots with reduced hot tops have also been measured and compared with those of conventional ingot products.

12.
Appl Opt ; 59(4): 991-997, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32225236

RESUMEN

Two types of phase-shifting algorithms were developed for simultaneous measurement of the surface and thickness variation of an optical flat. During wavelength tuning, phase-shift nonlinearity can cause a spatially nonuniform error and spatially uniform DC drift error. A 19-sample algorithm was developed that eliminates the effect of the spatially uniform error by expanding the 17-sample algorithm with characteristic polynomial theory. The 19-sample algorithm was then altered to measure the surface shape of the optical flat by rotation of the characteristic diagram. The surface shape and thickness variation were measured with these two algorithms and a wavelength-tuning Fizeau interferometer.

13.
Biom J ; 62(1): 24-33, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31544257

RESUMEN

In a longitudinal study where the recurrence of an event and a terminal event such as death are observed, a certain portion of the subjects may experience no event during a long follow-up period; this often denoted as the cure group which is assumed to be the risk-free from both recurrent events and death. However, this assumption ignores the possibility of death, which subjects in the cure group may experience. In the present study, such misspecification is investigated with the addition of a death hazard model to the cure group. We propose a joint model using a frailty effect, which reflects the association between a recurrent event and death. For the estimation, an expectation-maximization (EM) algorithm was developed and PROC NLMIXED in SAS was incorporated under a piecewise constant baseline. Simulation studies were performed to check the performance of the suggested method. The proposed method was applied to leukemia patients experiencing both infection and death after bone marrow transplant.


Asunto(s)
Biometría/métodos , Modelos Estadísticos , Ensayos Clínicos como Asunto , Humanos , Leucemia/tratamiento farmacológico , Estudios Longitudinales , Análisis Multivariante , Recurrencia
14.
PLoS One ; 14(4): e0215547, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31009513

RESUMEN

Glioblastoma multiforme is one of the most invasive type of glial tumors, which rapidly grows and commonly spreads into nearby brain tissue. It is a devastating brain cancer that often results in death within approximately 12 to 15 months after diagnosis. In this work, optimal control theory was applied to regulate intracellular signaling pathways of miR-451-AMPK-mTOR-cell cycle dynamics via glucose and drug intravenous administration infusions. Glucose level is controlled to activate miR-451 in the up-stream pathway of the model. A potential drug blocking the inhibitory pathway of mTOR by AMPK complex is incorporated to explore regulation of the down-stream pathway to the cell cycle. Both miR-451 and mTOR levels are up-regulated inducing cell proliferation and reducing invasion in the neighboring tissues. Concomitant and alternating glucose and drug infusions are explored under various circumstances to predict best clinical outcomes with least administration costs.


Asunto(s)
Proteínas Quinasas Activadas por AMP/genética , Neoplasias Encefálicas/genética , Glioblastoma/genética , MicroARNs/genética , Transducción de Señal/genética , Serina-Treonina Quinasas TOR/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Algoritmos , Antineoplásicos/farmacología , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/metabolismo , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glioblastoma/tratamiento farmacológico , Glioblastoma/metabolismo , Glucosa/metabolismo , Glucosa/farmacología , Humanos , Invasividad Neoplásica , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo
15.
Cancers (Basel) ; 11(2)2019 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-30781871

RESUMEN

It is well-known that the tumor microenvironment (TME) plays an important role in the regulation of tumor growth and the efficacy of anti-tumor therapies. Recent studies have demonstrated the potential of combination therapies, using oncolytic viruses (OVs) in conjunction with proteosome inhibitors for the treatment of glioblastoma, but the role of the TME in such therapies has not been studied. In this paper, we develop a mathematical model for combination therapies based on the proteosome inhibitor bortezomib and the oncolytic herpes simplex virus (oHSV), with the goal of understanding their roles in bortezomib-induced endoplasmic reticulum (ER) stress, and how the balance between apoptosis and necroptosis is affected by the treatment protocol. We show that the TME plays a significant role in anti-tumor efficacy in OV combination therapy, and illustrate the effect of different spatial patterns of OV injection. The results illustrate a possible phenotypic switch within tumor populations in a given microenvironment, and suggest new anti-invasion therapies.

16.
PLoS One ; 14(1): e0211041, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30689655

RESUMEN

Neutrophils display rapid and potent innate immune responses in various diseases. Tumor-associated neutrophils (TANs) however either induce or overcome immunosuppressive functions of the tumor microenvironment through complex tumor-stroma crosstalk. We developed a mathematical model to address the question of how phenotypic alterations between tumor suppressive N1 TANS, and tumor promoting N2 TANs affect nonlinear tumor growth in a complex tumor microenvironment. The model provides a visual display of the complex behavior of populations of TANs and tumors in response to various TGF-ß and IFN-ß stimuli. In addition, the effect of anti-tumor drug administration is incorporated in the model in an effort to achieve optimal anti-tumor efficacy. The simulation results from the mathematical model were in good agreement with experimental data. We found that the N2-to-N1 ratio (N21R) index is positively correlated with aggressive tumor growth, suggesting that this may be a good prognostic factor. We also found that the antitumor efficacy increases when the relative ratio (Dap) of delayed apoptotic cell death of N1 and N2 TANs is either very small or relatively large, providing a basis for therapeutically targeting prometastatic N2 TANs.


Asunto(s)
Neoplasias Pulmonares/metabolismo , Modelos Biológicos , Neutrófilos/metabolismo , Microambiente Tumoral , Humanos , Interferón beta/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Proteínas de Neoplasias/metabolismo , Neutrófilos/patología , Factor de Crecimiento Transformador beta/metabolismo
17.
PLoS One ; 13(10): e0204865, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30286133

RESUMEN

The cellular dispersion and therapeutic control of glioblastoma, the most aggressive type of primary brain cancer, depends critically on the migration patterns after surgery and intracellular responses of the individual cancer cells in response to external biochemical cues in the microenvironment. Recent studies have shown that miR-451 regulates downstream molecules including AMPK/CAB39/MARK and mTOR to determine the balance between rapid proliferation and invasion in response to metabolic stress in the harsh tumor microenvironment. Surgical removal of the main tumor is inevitably followed by recurrence of the tumor due to inaccessibility of dispersed tumor cells in normal brain tissue. In order to address this complex process of cell proliferation and invasion and its response to conventional treatment, we propose a mathematical model that analyzes the intracellular dynamics of the miR-451-AMPK- mTOR-cell cycle signaling pathway within a cell. The model identifies a key mechanism underlying the molecular switches between proliferative phase and migratory phase in response to metabolic stress in response to fluctuating glucose levels. We show how up- or down-regulation of components in these pathways affects the key cellular decision to infiltrate or proliferate in a complex microenvironment in the absence and presence of time delays and stochastic noise. Glycosylated chondroitin sulfate proteoglycans (CSPGs), a major component of the extracellular matrix (ECM) in the brain, contribute to the physical structure of the local brain microenvironment but also induce or inhibit glioma invasion by regulating the dynamics of the CSPG receptor LAR as well as the spatiotemporal activation status of resident astrocytes and tumor-associated microglia. Using a multi-scale mathematical model, we investigate a CSPG-induced switch between invasive and non-invasive tumors through the coordination of ECM-cell adhesion and dynamic changes in stromal cells. We show that the CSPG-rich microenvironment is associated with non-invasive tumor lesions through LAR-CSGAG binding while the absence of glycosylated CSPGs induce the critical glioma invasion. We illustrate how high molecular weight CSPGs can regulate the exodus of local reactive astrocytes from the main tumor lesion, leading to encapsulation of non-invasive tumor and inhibition of tumor invasion. These different CSPG conditions also change the spatial profiles of ramified and activated microglia. The complex distribution of CSPGs in the tumor microenvironment can determine the nonlinear invasion behaviors of glioma cells, which suggests the need for careful therapeutic strategies.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Matriz Extracelular/metabolismo , Glioblastoma/metabolismo , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/metabolismo , Microambiente Tumoral , Adenilato Quinasa/metabolismo , Sulfatos de Condroitina/metabolismo , Humanos , MicroARNs/genética , Modelos Teóricos , Invasividad Neoplásica , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo
18.
Opt Express ; 26(8): 10870-10878, 2018 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-29716017

RESUMEN

Wavelength-tuning interferometry has been widely used for measuring the thickness variation of optical devices used in the semiconductor industry. However, in wavelength-tuning interferometry, the nonlinearity of phase shift causes a spatially uniform error in the calculated phase distribution. In this study, the spatially uniform error is formulated using Taylor series. A new 9-sample phase-shifting algorithm is proposed, with which the uniform spatial phase error can be eliminated. The characteristics of 9-sample algorithm is discussed using Fourier representation and RMS error analysis. Finally, optical-thickness variation of transparent plate is measured using the proposed algorithm and wavelength-tuning Fizeau interferometer and the error is compared with 7-sample algorithm.

19.
Proc Natl Acad Sci U S A ; 115(19): 4927-4932, 2018 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-29686060

RESUMEN

In the present work, we investigated the role of natural killer (NK) cells in combination therapy with oncolytic virus (OV) and bortezomib, a proteasome inhibitor. NK cells display rapid and potent immunity to metastatic and hematological cancers, and they overcome immunosuppressive effects of tumor microenvironment. We developed a mathematical model to address the question of how the density of NK cells affects the growth of the tumor. We found that the antitumor efficacy increases when the endogenous NKs are depleted and also when exogenous NK cells are injected into the tumor. These predictions were validated by our in vivo and in vitro experiments.


Asunto(s)
Bortezomib/uso terapéutico , Neoplasias Hematológicas , Células Asesinas Naturales/inmunología , Modelos Inmunológicos , Viroterapia Oncolítica , Microambiente Tumoral , Animales , Línea Celular Tumoral , Chlorocebus aethiops , Neoplasias Hematológicas/inmunología , Neoplasias Hematológicas/patología , Neoplasias Hematológicas/terapia , Humanos , Células Asesinas Naturales/patología , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunología , Células Vero
20.
PLoS One ; 12(2): e0171312, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28166231

RESUMEN

Gliomas are malignant tumors that are commonly observed in primary brain cancer. Glioma cells migrate through a dense network of normal cells in microenvironment and spread long distances within brain. In this paper we present a two-dimensional multiscale model in which a glioma cell is surrounded by normal cells and its migration is controlled by cell-mechanical components in the microenvironment via the regulation of myosin II in response to chemoattractants. Our simulation results show that the myosin II plays a key role in the deformation of the cell nucleus as the glioma cell passes through the narrow intercellular space smaller than its nuclear diameter. We also demonstrate that the coordination of biochemical and mechanical components within the cell enables a glioma cell to take the mode of amoeboid migration. This study sheds lights on the understanding of glioma infiltration through the narrow intercellular spaces and may provide a potential approach for the development of anti-invasion strategies via the injection of chemoattractants for localization.


Asunto(s)
Glioma/metabolismo , Glioma/patología , Modelos Teóricos , Miosina Tipo II/metabolismo , Actinas/metabolismo , Algoritmos , Animales , Fenómenos Biomecánicos , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Factores Quimiotácticos/metabolismo , Difusión , Humanos , Invasividad Neoplásica , Ratas
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