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1.
Immunity ; 56(11): 2570-2583.e6, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37909039

RESUMO

Dimeric IgA (dIgA) can move through cells via the IgA/IgM polymeric immunoglobulin receptor (PIGR), which is expressed mainly on mucosal epithelia. Here, we studied the ability of dIgA to target commonly mutated cytoplasmic oncodrivers. Mutation-specific dIgA, but not IgG, neutralized KRASG12D within ovarian carcinoma cells and expelled this oncodriver from tumor cells. dIgA binding changed endosomal trafficking of KRASG12D from accumulation in recycling endosomes to aggregation in the early/late endosomes through which dIgA transcytoses. dIgA targeting of KRASG12D abrogated tumor cell proliferation in cell culture assays. In vivo, KRASG12D-specific dIgA1 limited the growth of KRASG12D-mutated ovarian and lung carcinomas in a manner dependent on CD8+ T cells. dIgA specific for IDH1R132H reduced colon cancer growth, demonstrating effective targeting of a cytoplasmic oncodriver not associated with surface receptors. dIgA targeting of KRASG12D restricted tumor growth more effectively than small-molecule KRASG12D inhibitors, supporting the potential of this approach for the treatment of human cancers.


Assuntos
Carcinoma , Imunoglobulina A , Humanos , Imunoglobulina A/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Citoplasma/metabolismo
2.
Immunity ; 55(1): 115-128.e9, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35021053

RESUMO

The immune checkpoint receptor PD-1 on T follicular helper (Tfh) cells promotes Tfh:B cell interactions and appropriate positioning within tissues. Here, we examined the impact of regulation of PD-1 expression by the genomic organizer SATB1 on Tfh cell differentiation. Vaccination of CD4CreSatb1f/f mice enriched for antigen-specific Tfh cells, and TGF-ß-mediated repression of SATB1 enhanced Tfh differentiation of human T cells. Mechanistically, high Icos expression in Satb1-/- CD4+ T cells promoted Tfh cell differentiation by preventing T follicular regulatory cell skewing and resulted in increased isotype-switched B cell responses in vivo. Ovarian tumors in CD4CreSatb1f/f mice accumulated tumor antigen-specific, LIGHT+CXCL13+IL-21+ Tfh cells and tertiary lymphoid structures (TLS). TLS formation decreased tumor growth in a CD4+ T cell and CXCL13-dependent manner. The transfer of Tfh cells, but not naive CD4+ T cells, induced TLS at tumor beds and decreased tumor growth. Thus, TGF-ß-mediated silencing of Satb1 licenses Tfh cell differentiation, providing insight into the genesis of TLS within tumors.


Assuntos
Centro Germinativo/imunologia , Linfócitos do Interstício Tumoral/imunologia , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Estruturas Linfoides Terciárias/imunologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Diferenciação Celular , Regulação da Expressão Gênica , Inativação Gênica , Genótipo , Proteínas de Ligação à Região de Interação com a Matriz/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Fator de Crescimento Transformador beta/genética
3.
Immunity ; 52(4): 668-682.e7, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32294407

RESUMO

The primary mechanisms supporting immunoregulatory polarization of myeloid cells upon infiltration into tumors remain largely unexplored. Elucidation of these signals could enable better strategies to restore protective anti-tumor immunity. Here, we investigated the role of the intrinsic activation of the PKR-like endoplasmic reticulum (ER) kinase (PERK) in the immunoinhibitory actions of tumor-associated myeloid-derived suppressor cells (tumor-MDSCs). PERK signaling increased in tumor-MDSCs, and its deletion transformed MDSCs into myeloid cells that activated CD8+ T cell-mediated immunity against cancer. Tumor-MDSCs lacking PERK exhibited disrupted NRF2-driven antioxidant capacity and impaired mitochondrial respiratory homeostasis. Moreover, reduced NRF2 signaling in PERK-deficient MDSCs elicited cytosolic mitochondrial DNA elevation and, consequently, STING-dependent expression of anti-tumor type I interferon. Reactivation of NRF2 signaling, conditional deletion of STING, or blockade of type I interferon receptor I restored the immunoinhibitory potential of PERK-ablated MDSCs. Our findings demonstrate the pivotal role of PERK in tumor-MDSC functionality and unveil strategies to reprogram immunosuppressive myelopoiesis in tumors to boost cancer immunotherapy.


Assuntos
Carcinoma Pulmonar de Lewis/imunologia , Carcinoma Epitelial do Ovário/imunologia , Regulação Neoplásica da Expressão Gênica , Melanoma Experimental/imunologia , Proteínas de Membrana/imunologia , Neoplasias Cutâneas/imunologia , eIF-2 Quinase/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Carcinoma Pulmonar de Lewis/genética , Carcinoma Pulmonar de Lewis/metabolismo , Carcinoma Pulmonar de Lewis/patologia , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/metabolismo , Carcinoma Epitelial do Ovário/patologia , Feminino , Humanos , Terapia de Imunossupressão , Interferon-alfa/genética , Interferon-alfa/imunologia , Interferon beta/genética , Interferon beta/imunologia , Masculino , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/imunologia , Mitocôndrias/metabolismo , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/patologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/imunologia , Receptores de Interferon/genética , Receptores de Interferon/imunologia , Transdução de Sinais , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Resposta a Proteínas não Dobradas/imunologia , eIF-2 Quinase/deficiência , eIF-2 Quinase/genética
4.
Nature ; 591(7850): 464-470, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536615

RESUMO

Most ovarian cancers are infiltrated by prognostically relevant activated T cells1-3, yet exhibit low response rates to immune checkpoint inhibitors4. Memory B cell and plasma cell infiltrates have previously been associated with better outcomes in ovarian cancer5,6, but the nature and functional relevance of these responses are controversial. Here, using 3 independent cohorts that in total comprise 534 patients with high-grade serous ovarian cancer, we show that robust, protective humoral responses are dominated by the production of polyclonal IgA, which binds to polymeric IgA receptors that are universally expressed on ovarian cancer cells. Notably, tumour B-cell-derived IgA redirects myeloid cells against extracellular oncogenic drivers, which causes tumour cell death. In addition, IgA transcytosis through malignant epithelial cells elicits transcriptional changes that antagonize the RAS pathway and sensitize tumour cells to cytolytic killing by T cells, which also contributes to hindering malignant progression. Thus, tumour-antigen-specific and -antigen-independent IgA responses antagonize the growth of ovarian cancer by governing coordinated tumour cell, T cell and B cell responses. These findings provide a platform for identifying targets that are spontaneously recognized by intratumoural B-cell-derived antibodies, and suggest that immunotherapies that augment B cell responses may be more effective than approaches that focus on T cells, particularly for malignancies that are resistant to checkpoint inhibitors.


Assuntos
Antígenos de Neoplasias/imunologia , Imunoglobulina A/imunologia , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/patologia , Linfócitos T Citotóxicos/imunologia , Transcitose , Especificidade de Anticorpos , Antígenos CD/imunologia , Linhagem Celular , Progressão da Doença , Feminino , Humanos , Neoplasias Ovarianas/prevenção & controle , Receptores Fc/imunologia , Família de Moléculas de Sinalização da Ativação Linfocitária/imunologia , Transcitose/imunologia , Microambiente Tumoral/imunologia
5.
Semin Immunol ; 65: 101707, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36527759

RESUMO

Immuno-oncology has traditionally focused on the cellular arm of the adaptive immune response, while attributing tumor-promoting activity to humoral responses in tumor-bearing hosts. This view stems from mouse models that do not necessarily recapitulate the antibody response process consistently observed in most human cancers. In recent years, the field has reconsidered the coordinated action of T and B cell responses in the context of anti-tumor immunity, as in any other immune response. Thus, recent studies in human cancer identify B cell responses with better outcome, typically in association with superior T cell responses. An area of particular interest is tertiary lymphoid structures, where germinal centers produce isotype switched antibodies and B cells and T lymphocytes interact with other immune cell types. The presence of these lymphoid structures is associated with better immunotherapeutic responses and remain poorly understood. Here, we discuss recent discoveries on how coordination between humoral and cellular responses is required for effective immune pressure against malignant progression, providing a perspective on the role of tertiary lymphoid structures and interventions to elicit their formation in unresectable tumors.


Assuntos
Linfócitos B , Neoplasias , Linfócitos T , Estruturas Linfoides Terciárias , Animais , Humanos , Camundongos , Imunidade Adaptativa/imunologia , Linfócitos B/imunologia , Neoplasias/imunologia , Neoplasias/terapia , Linfócitos T/imunologia , Estruturas Linfoides Terciárias/imunologia
6.
Semin Immunol ; 49: 101419, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-33183950

RESUMO

Solid cancers progress from primordial lesions through complex interactions between tumor-promoting and anti-tumor immune cell types, ultimately leading to the orchestration of humoral and T cell adaptive immune responses, albeit in an immunosuppressive environment. B cells infiltrating most established tumors have been associated with a dual role: Some studies have associated antibodies produced by tumor-associated B cells with the promotion of regulatory activities on myeloid cells, and also with direct immunosuppression through the production of IL-10, IL-35 or TGF-ß. In contrast, recent studies in multiple human malignancies identify B cell responses with delayed malignant progression and coordinated T cell protective responses. This includes the elusive role of Tertiary Lymphoid Structures identified in many human tumors, where the function of B cells remains unknown. Here, we discuss emerging data on the dual role of B cell responses in the pathophysiology of human cancer, providing a perspective on future directions and possible novel interventions to restore the coordinated action of both branches of the adaptive immune response, with the goal of maximizing immunotherapeutic effectiveness.


Assuntos
Linfócitos B/imunologia , Imunidade Humoral , Neoplasias/etiologia , Animais , Linfócitos B/metabolismo , Biomarcadores , Citocinas/metabolismo , Gerenciamento Clínico , Suscetibilidade a Doenças , Humanos , Imunomodulação , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/terapia , Microambiente Tumoral/imunologia
7.
Gynecol Oncol ; 173: 114-121, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37121178

RESUMO

OBJECTIVE: To demonstrate that shared antibody responses in endometriosis and endometriosis-associated ovarian cancer spontaneously antagonize malignant progression and can be leveraged to develop future immunotherapies. METHODS: B cells from cyopreserved clear cell ovarian carcinoma (CCC, n = 2), endometrioid ovarian carcinoma (EC, n = 2), and endometriomas (n = 2) were isolated, activated, and EBV-immortalized. Antibodies were purified from B cell supernatants and used for screening arrays containing most of the human proteome. Targets were prioritized based on accessibility (transmembrane or secreted proteins), expression in endometriosis and cancer, and concurrent IgA and IgG responses. We focused on antibodies targeting tumor-promoting syndecan binding protein (SDCBP) to demonstrate anti-tumor activity. Immunoblots and qPCR were performed to assess SDCBP expression in ovarian cancer and endometriosis cell lines and tumor samples. Recombinant IgG4 was generated using the variable heavy and light chains of dominant B cell receptors (BCRs) reacting against the extracellular domain of SDCBP, and used in in vivo studies in human CCC- and high-grade serous ovarian carcinoma (HGSOC)-bearing immunodeficient mice. RESULTS: Nine accessible proteins detected by both IgA and IgG were identified in all samples - including SDCBP, which is expressed in ovarian carcinomas of multiple histologies. Administration of α-SDCBP IgG4 in OVCAR3 (HGSOC), TOV21G and RMG-I (CCC) tumor-bearing mice significantly decreased tumor volume compared to control irrelevant IgG4. CONCLUSIONS: Spontaneous antibody responses exert suboptimal but measurable immune pressure against malignant progression in ovarian carcinomas. Using tumor-derived antibodies for developing novel immunotherapeutics warrants further investigation.


Assuntos
Adenocarcinoma de Células Claras , Carcinoma Endometrioide , Endometriose , Neoplasias Ovarianas , Humanos , Feminino , Animais , Camundongos , Neoplasias Ovarianas/patologia , Apoptose , Formação de Anticorpos , Linhagem Celular Tumoral , Carcinoma Epitelial do Ovário , Carcinoma Endometrioide/patologia , Imunoglobulina A/metabolismo , Adenocarcinoma de Células Claras/patologia , Sinteninas/metabolismo
8.
Org Biomol Chem ; 21(8): 1657-1661, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36727302

RESUMO

An iron oxide nanocatalyst supported on a potassium exchanged zeolite-Y (Fe2O3-KY) is an efficient and reusable catalyst that promotes the selective α-H functionalization of 2-naphthols with various aromatic primary alcohols. The reaction occurs at 110 °C in dichloroethane and requires 6 h for completion. The product yields were found to vary with respect to the nature of the substituents. Benzyl alcohols with electron-donating groups gave the highest yields of up to 90%.

9.
Sensors (Basel) ; 22(7)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35408129

RESUMO

A lightweight on-device liquid consumption estimation system involving an energy-aware machine learning algorithm is developed in this work. This system consists of two separate on-device neural network models that carry out liquid consumption estimation with the result of two tasks: the detection of sip from gestures with which the bottle is handled by its user and the detection of first sips after a bottle refill. This predictive volume estimation framework incorporates a self-correction mechanism that can minimize the error after each bottle fill-up cycle, which makes the system robust to errors from the sip classification module. In this paper, a detailed characterization of sip detection is performed to understand the accuracy-complexity tradeoffs by developing and implementing a variety of different ML models with varying complexities. The maximum energy consumed by the entire framework is around 119 mJ during a maximum computation time of 300 µs. The energy consumption and computation times of the proposed framework is suitable for implementation in low-power embedded hardware that can be incorporated in consumer grade water bottles.


Assuntos
Algoritmos , Redes Neurais de Computação , Computadores , Gestos , Aprendizado de Máquina
10.
J Immunol ; 203(12): 3447-3460, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31704881

RESUMO

Tumor-associated macrophages are major contributors to malignant progression and resistance to immunotherapy, but the mechanisms governing their differentiation from immature myeloid precursors remain incompletely understood. In this study, we demonstrate that exosomes secreted by human and mouse tumor-educated mesenchymal stem cells (MSCs) drive accelerated breast cancer progression by inducing differentiation of monocytic myeloid-derived suppressor cells into highly immunosuppressive M2-polarized macrophages at tumor beds. Mechanistically, MSC-derived exosomes but not exosomes from tumor cells contain TGF-ß, C1q, and semaphorins, which promote myeloid tolerogenic activity by driving PD-L1 overexpression in both immature myelomonocytic precursors and committed CD206+ macrophages and by inducing differentiation of MHC class II+ macrophages with enhanced l-Arginase activity and IL-10 secretion at tumor beds. Accordingly, administration of tumor-associated murine MSC-derived exosomes accelerates tumor growth by dampening antitumor immunity, and macrophage depletion eliminates exosome-dependent differences in malignant progression. Our results unveil a new role for MSC-derived exosomes in the differentiation of myeloid-derived suppressor cells into macrophages, which governs malignant growth.


Assuntos
Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Exossomos/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células Mieloides/metabolismo , Animais , Biomarcadores Tumorais , Neoplasias da Mama/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Técnicas de Cocultura , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal , Feminino , Xenoenxertos , Humanos , Imunomodulação , Imunofenotipagem , Ativação de Macrófagos/imunologia , Macrófagos/patologia , Camundongos , Células Mieloides/citologia
11.
J Appl Biomech ; 37(3): 215-223, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33631718

RESUMO

Impairment of arm movements poststroke often results in the use of compensatory trunk movements to complete motor tasks. These compensatory movements have been mostly observed in tightly controlled conditions, with very few studies examining them in more naturalistic settings. In this study, the authors quantified the presence of compensatory movements during a set of continuous reaching and manipulation tasks performed with both the paretic and nonparetic arm (in 9 chronic stroke survivors) or the dominant arm (in 20 neurologically unimpaired control participants). Kinematic data were collected using motion capture to assess trunk and elbow movement. The authors found that trunk displacement and rotation were significantly higher when using the paretic versus nonparetic arm (P = .03). In contrast, elbow angular displacement was significantly lower in the paretic versus nonparetic arm (P = .01). The reaching tasks required significantly higher trunk compensation and elbow movement than the manipulation tasks. These results reflect increased reliance on compensatory trunk movements poststroke, even in everyday functional tasks, which may be a target for home rehabilitation programs. This study provides a novel contribution to the rehabilitation literature by examining the presence of compensatory movements in naturalistic reaching and manipulation tasks.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Braço , Fenômenos Biomecânicos , Humanos , Movimento , Sobreviventes , Tronco
13.
Sensors (Basel) ; 19(18)2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31533275

RESUMO

Various sensors have been proposed to address the negative health ramifications of inadequate fluid consumption. Amongst these solutions, motion-based sensors estimate fluid intake using the characteristics of drinking kinematics. This sensing approach is complicated due to the mutual influence of both the drink volume and the current fill level on the resulting motion pattern, along with differences in biomechanics across individuals. While motion-based strategies are a promising approach due to the proliferation of inertial sensors, previous studies have been characterized by limited accuracy and substantial variability in performance across subjects. This research seeks to address these limitations for a container-attachable triaxial accelerometer sensor. Drink volume is computed using support vector machine regression models with hand-engineered features describing the container's estimated inclination. Results are presented for a large-scale data collection consisting of 1908 drinks consumed from a refillable bottle by 84 individuals. Per-drink mean absolute percentage error is reduced by 11.05% versus previous state-of-the-art results for a single wrist-wearable inertial measurement unit (IMU) sensor assessed using a similar experimental protocol. Estimates of aggregate consumption are also improved versus previously reported results for an attachable sensor architecture. An alternative tracking approach using the fill level from which a drink is consumed is also explored herein. Fill level regression models are shown to exhibit improved accuracy and reduced inter-subject variability versus volume estimators. A technique for segmenting the entire drink motion sequence into transport and sip phases is also assessed, along with a multi-target framework for addressing the known interdependence of volume and fill level on the resulting drink motion signature.

14.
Biochim Biophys Acta Mol Basis Dis ; 1864(6 Pt A): 2053-2066, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29526821

RESUMO

The multifunctional cytokine TGF-ß crucially participates in breast cancer (BCa) metastasis and works differently in the disease stages, thus contributing in BCa progression. We address connections between TGF-ß and the stem cell-related transcription factor (TF) Oct4 in BCa. In 147 BCa patients with infiltrating duct carcinoma, we identified a significantly higher number of cases with both moderate/high Oct4 expression and high TGF-ß in late stages compared to early stages of the disease. In vitro studies showed that TGF-ß elevated Oct4 expression, which in turn, regulated Epithelial-to-Mesenchymal transition (EMT)-regulatory gene (Snail and Slug) expression, migratory ability, chemotactic invasiveness and extracellular matrix (ECM) degradation potential of BCa cells. Putative binding sites for Oct4 on the snail, slug and cxcl13 promoters and for Smad3 on the snail and slug promoters were identified. Promoter activities of snail and slug were greater in dual-treated cells than only TGF-ß-treated or Oct4-overexpressing cells. CXCL13 mRNA fold changes, however, were low in cells induced with TGF-ß, compared to dual-treated or Oct4-overexpressing cells. Our co-IP studies confirmed that Oct4 and Smad3 form heterodimers that recognize specific promoter sequences to promote Snail and Slug expression, but which in turn, indirectly inhibits Smad3-mediated repression of CXCL13 expression, allowing Oct4 to act as a positive TF for CXCL13. Taken together, these data suggest that TGF-ß signaling and Oct4 cooperate to induce expression of EMT-related genes Snail, Slug and CXCL13, which accelerates disease progression, particularly in the late stages, and may indicate a poor prognosis for BCa patients.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Fator 3 de Transcrição de Octâmero/metabolismo , Proteína Smad3/metabolismo , Fatores de Transcrição da Família Snail/genética , Adulto , Idoso , Mama/patologia , Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Biologia Computacional , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Regiões Promotoras Genéticas , Multimerização Proteica , Transdução de Sinais/genética , Fatores de Transcrição da Família Snail/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Adulto Jovem
15.
Biochem Biophys Res Commun ; 482(1): 126-133, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27720715

RESUMO

Breast cancer is the most deadly cancer among women and the second leading cause of cancer death worldwide. Treatment effectiveness is complicated with tumor invasiveness/drug resistance. To tailor treatments more effectively to individual patients, it is important to define tumor growth and metastasis at molecular levels. SDCBP is highly overexpressed and associated with a strikingly poor prognosis in breast cancer. However the post transcriptional regulation of SDCBP overexpression remains to be an unexplored area. Our study reveals that miR-216b directly regulates SDCBP expression by binding to its 3'UTR region. miR-216b is a tumor suppressive miRNA and it is underexpressed during metastatic breast cancer. Consequently, overexpression of miR-216b resulted in decreased proliferation, migration and invasion in BC cell lines by modulating the expression of SDCBP. Inhibition of miR-216b divergent the tumor suppressive role by inducing the growth proliferation, migration and invasion in vitro. There is therefore a negative correlation between the expression of miR-216b and its target gene SDCBP in the BC tissue samples as well as cell lines. Simultaneous expression of miR-216b and SDCBP rescued the growth, migration and invasion effect suggesting that tumor suppressive action of miR-216b may be directly mediated by SDCBP. In summary, the study identifies miR-216b as a regulator of SDCBP expression in breast cancer which can potentially be targeted for developing newer therapies for the effective treatment of this killer disease.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/secundário , Proliferação de Células/genética , Genes Supressores de Tumor , MicroRNAs/metabolismo , Sinteninas/genética , Neoplasias da Mama/patologia , Feminino , Humanos , Células Tumorais Cultivadas
16.
J Sports Sci ; 34(21): 2130-9, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26942316

RESUMO

The purpose of this study was to validate a wireless network of accelerometers and compare it to a hip-mounted accelerometer for predicting energy expenditure in a semi-structured environment. Adults (n = 25) aged 18-30 engaged in 14 sedentary, ambulatory, exercise, and lifestyle activities over a 60-min protocol while wearing a portable metabolic analyser, hip-mounted accelerometer, and wireless network of three accelerometers worn on the right wrist, thigh, and ankle. Participants chose the order and duration of activities. Artificial neural networks were created separately for the wireless network and hip accelerometer for energy expenditure prediction. The wireless network had higher correlations (r = 0.79 vs. r = 0.72, P < 0.01) but similar root mean square error (2.16 vs. 2.09 METs, P > 0.05) to the hip accelerometer. Measured (from metabolic analyser) and predicted energy expenditure from the hip accelerometer were significantly different for the 3 of the 14 activities (lying down, sweeping, and cycle fast); conversely, measured and predicted energy expenditure from the wireless network were not significantly different for any activity. In conclusion, the wireless network yielded a small improvement over the hip accelerometer, providing evidence that the wireless network can produce accurate estimates of energy expenditure in adults participating in a range of activities.


Assuntos
Acelerometria/métodos , Metabolismo Energético , Exercício Físico , Monitorização Ambulatorial/métodos , Esforço Físico , Adolescente , Adulto , Feminino , Humanos , Extremidade Inferior , Masculino , Redes Neurais de Computação , Reprodutibilidade dos Testes , Comportamento Sedentário , Punho , Adulto Jovem
17.
J Med Biol Eng ; 36(6): 765-775, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28111533

RESUMO

Self-reported questionnaires are widely used by researchers for analyzing the dietary behavior of overweight and obese individuals. It has been established that questionnaire-based data collection often suffers from high errors due to its reporting subjectivity. Automatic swallow detection, as an alternative to questionnaires, is proposed in this paper to avoid such subjectivity. Existing approaches for swallow detection include the use of surface electromyography and sound to detect individual swallowing events. Many of these methods are generally too complicated and cumbersome for daily usage in a free-living setting. This paper presents a wearable solid food intake monitoring system that analyzes human breathing signals and swallow sequence locality. Food intake is identified by detecting swallow events. The system works based on a key observation that the otherwise continuous breathing process is interrupted by a short apnea during swallowing. A support vector machine (SVM) is first used for detecting such apneas in breathing signals collected from a wearable chest belt. The resulting swallow detection is then refined using a hidden Markov model (HMM)-based mechanism that leverages the known temporal locality in the sequence of human swallows. Temporal locality is based on the fact that people usually do not swallow in consecutive breathing cycles. The HMM model is used to model such temporal locality in order to refine the SVM results. Experiments were carried out on six healthy subjects wearing the proposed system. The proposed SVM method achieved up to 61% precision and 91% recall on average. Utilization of HMM in addition to SVM improved the overall performance to up to 75% precision and 86% recall.

18.
Mol Carcinog ; 54(12): 1636-55, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25358602

RESUMO

Reactive oxygen species (ROS), the key mediators of cellular oxidative stress and redox dysregulation involved in cancer initiation and progression, have recently emerged as promising targets for anticancer drug discovery. Continuous free radical assault upsets homeostasis in cellular redox system and regulates the associated signaling pathways to mediate stress-induced cell death. This study investigates the dose-specific pro-oxidative behavior of a bacterial fucose polysaccharide, which attenuated proliferation of different cancer cells. In the fermentation process, Bacillus megaterium RB-05 [GenBank Accession Number HM371417] was found to biosynthesize a polysaccharide with low-fucose content (4.9%), which conferred the maximum anti-proliferative activity (750 µg/mL) against human lung cancer epithelial cells (A549) during preliminary screening. Structural elucidation and morphological characterization of the duly purified polysaccharide was done using HPLC, GC-MS, (1)H/(13)C NMR, and microscopy. The polysaccharide exhibited concentration- and time-dependent anti-proliferative effects against A549 cells by inducing intracellular ROS level and regulating the mitochondrial membrane-permeability following the apoptotic pathway. This process encompasses activation of caspase-8/9/3/7, increase in the ratio of Bax/Bcl2 ratio, translocation of Bcl2-associated X protein (Bax) and cytochrome c, decrease in expression of anti-apoptotic members of Bcl2 family, and phosphorylation of mitogen activated protein kinases (MAPKs). Apoptosis was attenuated upon pretreatment with specific caspase-inhibitors. Simultaneously, during apoptosis, the ROS-mediated stress as well as activated MAPKs triggered nuclear translocation of transcription factors like nuclear factor (erythroid-derived)-like 2 (Nrf2) and promoted further transcription of downstream cytoprotective genes, which somehow perturbed the chemotherapeutic efficacy of the polysaccharide, although using CuPP, a chemical inhibitor of HO-1, apoptosis increased significantly (P < 0.05).


Assuntos
Apoptose/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Pulmonares/metabolismo , Mitocôndrias/efeitos dos fármacos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Polissacarídeos Bacterianos/farmacologia , Proteínas Reguladoras de Apoptose/metabolismo , Carcinoma/metabolismo , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Fucose/farmacologia , Células HeLa , Homeostase/efeitos dos fármacos , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch , Células MCF-7 , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
19.
Breast Cancer Res Treat ; 143(2): 265-76, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24337540

RESUMO

We investigated the expression of -CXC chemokine ligand 13 (CXCL13) and its receptor -CXC chemokine receptor 5 (CXCR5) in 98 breast cancer (BC) patients with infiltrating duct carcinoma, out of which 56 were found lymph node metastasis (LNM) positive. Interestingly, co-expression of CXCL13 and CXCR5 showed a significant correlation with LNM. Since, epithelial to mesenchymal transition (EMT) is highly associated with metastasis we investigated EMT-inducing potential of CXCL13 in BC cell lines. In CXCL13-stimulated BC cells, expression of various mesenchymal markers (Vimentin, N-cadherin), EMT regulators (Snail, Slug), and matrix metalloproteinase-9 (MMP9) was increased, whereas the expression of epithelial marker E-cadherin was found to be decreased. In addition, expression of receptor activator of nuclear factor kappa-B ligand (RANKL), which is known to regulate MMP9 expression via Src activation, was also significantly increased after CXCL13 stimulation. Using specific protein kinase inhibitors, we confirmed that CXCL13 stimulated EMT and MMP9 expression via RANKL-Src axis in BC cell lines. To further validate this observation, we examined gene expression patterns in primary breast tumors and detected significantly higher expression of various mesenchymal markers and regulators in CXCL13-CXCR5 co-expressing patients. Therefore, this study showed the EMT-inducing potential of CXCL13 as well as demonstrated the prognostic value of CXCL13-CXCR5 co-expression in primary BC. Moreover, CXCL13-CXCR5-RANKL-Src axis may present a therapeutic target in LNM positive BC patients.


Assuntos
Neoplasias da Mama/patologia , Quimiocina CXCL13/metabolismo , Transição Epitelial-Mesenquimal , Metástase Linfática/patologia , Receptores CXCR5/metabolismo , Adulto , Idoso , Antígenos CD/biossíntese , Biomarcadores Tumorais/metabolismo , Caderinas/biossíntese , Linhagem Celular Tumoral , Movimento Celular , Quimiocina CXCL13/antagonistas & inibidores , Quimiocina CXCL13/biossíntese , Feminino , Furanos/farmacologia , Humanos , Indóis/farmacologia , Metaloproteinase 9 da Matriz/biossíntese , Pessoa de Meia-Idade , Inibidores de Fosfoinositídeo-3 Quinase , Piridinas/farmacologia , Pirimidinas/farmacologia , Ligante RANK/biossíntese , Ligante RANK/genética , RNA Mensageiro/biossíntese , Receptores CXCR5/antagonistas & inibidores , Receptores CXCR5/biossíntese , Transdução de Sinais , Fatores de Transcrição da Família Snail , Sulfonamidas/farmacologia , Fatores de Transcrição/biossíntese , Vimentina/biossíntese , Quinases da Família src/antagonistas & inibidores
20.
PLoS One ; 19(5): e0303949, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38805441

RESUMO

Cognitive rehabilitation, STEM (science, technology, engineering, and math) skill acquisition, and coaching games such as chess often require tutoring decision-making strategies. The advancement of AI-driven tutoring systems for facilitating human learning requires an understanding of the impact of evaluative feedback on human decision-making and skill development. To this end, we conduct human experiments using Amazon Mechanical Turk to study the influence of evaluative feedback on human decision-making in sequential tasks. In these experiments, participants solve the Tower of Hanoi puzzle and receive AI-generated feedback while solving it. We examine how this feedback affects their learning and skill transfer to related tasks. Additionally, treating humans as noisy optimal agents, we employ maximum entropy inverse reinforcement learning to analyze the effect of feedback on the implicit human reward structure that guides their decision making. Lastly, we explore various computational models to understand how people incorporate evaluative feedback into their decision-making processes. Our findings underscore that humans perceive evaluative feedback as indicative of their long-term strategic success, thus aiding in skill acquisition and transfer in sequential decision-making tasks. Moreover, we demonstrate that evaluative feedback fosters a more structured and organized learning experience compared to learning without feedback. Furthermore, our results indicate that providing intermediate goals alone does not significantly enhance human learning outcomes.


Assuntos
Tomada de Decisões , Aprendizagem , Humanos , Aprendizagem/fisiologia , Masculino , Feminino , Adulto , Adulto Jovem , Inteligência Artificial , Reforço Psicológico
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