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1.
Expert Rev Clin Immunol ; : 1-14, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38712535

RESUMO

INTRODUCTION: Vasculogenic mimicry (VM) alludes to the ability of cancer cells to organize on three-dimensional channel-like structures to obtain nutrients and oxygen. This mechanism confers an aggressive phenotype, metastatic potential, and resistance to chemotherapy resulting in a poor prognosis. Recent studies have been focused on the identification of microRNAs (miRNAs) that regulate the VM representing potential therapeutic targets in cancer. AREAS COVERED: An overview of the roles of miRNAs on VM development and their functional relationships with tumor microenvironment. The functions of cancer stem-like cells in VM, and resistance to therapy are also discussed. Moreover, the modulation of VM by natural compounds is explored. The clinical significance of deregulated miRNAs as potential therapeutic targets in tumors showing VM is further highlighted. EXPERT OPINION: The miRNAs are regulators of protein-encoding genes involved in VM; however, their specific expression signatures with clinical value in large cohorts of patients have not been established yet. We considered that genomic profiling of miRNAs could be useful to define some hallmarks of tumors such as stemness, drug resistance, and VM in cancer patients. However, additional studies are needed to establish the relevant role of miRNAs as effective therapeutic targets in tumors that have developed VM.

2.
Mol Carcinog ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629425

RESUMO

Breast cancer is the most frequent neoplasia in developed countries and the leading cause of death in women worldwide. Epithelial-to-mesenchymal transition (EMT) is a cellular process through which epithelial cells decrease or lose their epithelial characteristics and gain mesenchymal properties. EMT mediates tumor progression, because tumor cells acquire the capacity to execute the multiple steps of invasion and metastasis. Benzo[a]pyrene (B[a]P) is an environmental organic pollutant generated during the burning of fossil fuels, wood, and other organic materials. B[a]P exposition increases the incidence of breast cancer, and induces migration and/or invasion in MDA-MB-231 and MCF-7 breast cancer cells. However, the role of B[a]P in the induction of an EMT process and metastasis of mammary carcinoma cells has not been studied in detail. In this study, we demonstrate that B[a]P induces an EMT process in MCF10A mammary non-tumorigenic epithelial cells. In addition, B[a]P promotes the formation of larger tumors in Balb/cJ mice inoculated with 4T1 cells than in untreated mice and treated with dimethyl sulfoxide (DMSO). B[a]P also increases the number of mice with metastasis to brain and the total number of brain metastatic nodules in Balb/cJ mice inoculated with 4T1 cells compared with untreated mice and treated with DMSO. In conclusion, B[a]P induces an EMT process in MCF10A cells and the growth of mammary tumors and metastasis to brain in Balb/cJ mice inoculated with 4T1 cells.

3.
Noncoding RNA ; 10(1)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38392969

RESUMO

Tumors have high requirements in terms of nutrients and oxygen. Angiogenesis is the classical mechanism for vessel formation. Tumoral vascularization has the function of nourishing the cancer cells to support tumor growth. Vasculogenic mimicry, a novel intratumoral microcirculation system, alludes to the ability of cancer cells to organize in three-dimensional (3D) channel-like architectures. It also supplies the tumors with nutrients and oxygen. Both mechanisms operate in a coordinated way; however, their functions in breast cancer stem-like cells and their regulation by microRNAs remain elusive. In the present study, we investigated the functional role of microRNA-204 (miR-204) on angiogenesis and vasculogenic mimicry in breast cancer stem-like cells. Using flow cytometry assays, we found that 86.1% of MDA-MB-231 and 92% of Hs-578t breast cancer cells showed the CD44+/CD24- immunophenotype representative of cancer stem-like cells (CSCs). The MDA-MB-231 subpopulation of CSCs exhibited the ability to form mammospheres, as expected. Interestingly, we found that the restoration of miR-204 expression in CSCs significantly inhibited the number and size of the mammospheres. Moreover, we found that MDA-MB-231 and Hs-578t CSCs efficiently undergo angiogenesis and hypoxia-induced vasculogenic mimicry in vitro. The transfection of precursor miR-204 in both CSCs was able to impair the angiogenesis in the HUVEC cell model, which was observed as a diminution in the number of polygons and sprouting cells. Remarkably, miR-204 mimics also resulted in the inhibition of vasculogenic mimicry formation in MDA-MB-231 and Hs-578t CSCs, with a significant reduction in the number of channel-like structures and branch points. Mechanistically, the effects of miR-204 were associated with a diminution of pro-angiogenic VEGFA and ß-catenin protein levels. In conclusion, our findings indicated that miR-204 abrogates the angiogenesis and vasculogenic mimicry development in breast cancer stem-like cells, suggesting that it could be a potential tool for breast cancer intervention based on microRNA replacement therapies.

4.
Transl Oncol ; 33: 101680, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37121177

RESUMO

Tumor cells grow in three-dimensional (3D) channels-like structures denoted as vasculogenic mimicry (VM), which provides a route for nutrients and oxygen acquisition. VM is activated by hypoxia and associated with metastasis and poor prognosis. MetastamiRs are microRNAs regulating metastasis, however, if they control VM in breast cancer remains poorly understood. The aim of this study was to evaluate the expression of VM-associated microRNAs in tumors of metastatic breast cancer patients. Firstly, we constructed microRNAs/mRNAs coregulation networks using expression data from TCGA databases. Dozens of microRNAs regulating genes involved in VM and metastasis were found. Of these, we selected 10 microRNAs for further characterization. The presence of VM in histological samples from patients with or without metastasis was evaluated using CD31-/PAS+ immunophenotyping. Remarkably, data showed that VM was significantly increased in tumors from patients with metastasis in comparison with no-metastatic group. Gene expression analysis indicated that miR-145, miR-142-3p, miR-31, miR-148a, miR-200b-3p and miR-526b were downregulated in primary tumors from patients with metastatic disease and positive for VM. Moreover, modulated microRNAs showed a predictive clinical value in overall survival in a cohort (n=1262) of breast cancer patients. Of these, we evaluated the role of miR-145 in formation of hypoxia-induced 3D channels-like using an in vitro model that recapitulates the early stages of VM. Data showed that miR-145 mimics was able to abolish the VM development in both metastatic Hs578t and MDA-MB-231 breast cancer cells. In conclusion, manipulation of miR-145 levels may represent a therapeutic approach in metastatic breast cancer patients that developed VM.

5.
J Membr Biol ; 256(1): 79-90, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35751654

RESUMO

Caveolae are small plasma membrane invaginations constituted for membrane proteins namely caveolins and cytosolic proteins termed cavins, which can occupy up to 50% of the surface of mammalian cells. The caveolae have been involved with a variety of cellular processes including regulation of cellular signaling. Insulin is a hormone that mediates a variety of physiological processes through activation of insulin receptor (IR), which is a tyrosine kinase receptor expressed in all mammalian tissues. Insulin induces activation of signal transducers and activators of transcription (STAT) family members including STAT5. In this study, we demonstrate, for the first time, that insulin induces phosphorylation of STAT5 at tyrosine-694 (STAT5-Tyr(P)694), STAT5 nuclear accumulation and an increase in STAT5-DNA complex formation in MCF-7 breast cancer cells. Insulin also induces nuclear accumulation of STAT5-Tyr(P)694, caveolin-1, and IR in MCF-7 cells. STAT5 nuclear accumulation and the increase of STAT5-DNA complex formation require the integrity of caveolae and microtubule network. Moreover, insulin induces an increase and nuclear accumulation of STAT5-Tyr(P)694 in MDA-MB-231 breast cancer cells. In conclusion, results demonstrate that caveolae and microtubule network play an important role in STAT5-Tyr(P)694, STAT5 nuclear accumulation and STAT5-DNA complex formation induced by insulin in breast cancer cells.


Assuntos
Neoplasias da Mama , Cavéolas , Animais , Humanos , Feminino , Cavéolas/metabolismo , Insulina/farmacologia , Insulina/metabolismo , Células MCF-7 , Fator de Transcrição STAT5/metabolismo , Neoplasias da Mama/metabolismo , Caveolina 1/genética , Caveolina 1/metabolismo , Fosforilação , Tirosina/metabolismo , DNA/metabolismo , Mamíferos/metabolismo
6.
Heliyon ; 8(11): e11405, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36387436

RESUMO

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype due to its greater invasive capacity and non-response to hormone therapy. Several species of the Ficus genus have been used as an alternative to traditional medicine against malignant diseases. Previously, leaf extracts from Ficus crocata (Miq.) Mart. ex Miq. (F. crocata) showed antiproliferative activity in vitro against breast and cervical tumor cells without having a cytotoxic effect on non-tumor cell lines. The purpose of the study was to evaluate the effect of hexane (Hex-EFc), dichloromethane (Dic-EFc), and acetone (Ace-EFc) extracts from F. crocata on the proliferative and invasive capacity of breast cancer cells MCF-7 and MDA-MB-231. Materials and methods: The phytochemical profile was carried out by gas chromatography-mass spectrometry (GC-MS). Cell proliferation, migration, and invasion were determined by MTT, wound closure, and transwell assays, respectively. MMPs activity was analyzed using gelatin zymography, and fluorescence microscopy was used to visualize F-actin distribution. Results: Hex-EFc, Dic-EFc, and Ace-EFc showed cytotoxic activity on MDA-MB-231 tumor cells and, to a lesser extent, on MCF-7 cells, without presenting cytotoxicity at the same concentrations in MCF-10A non-tumor cells. Dic-EFc and Ace-EFc (5-10 µg/mL) reduced the migration capacity of MCF-7 and MDA-MB-231 cells. Interestingly, exposure to Dic-EFc and Ace-EFc (5-10 µg/mL) inhibited the invasive ability of MDA-MB-231 cells, reducing the secretion and activity of MMP-2 and MMP-9, as well as the F-actin distribution. Conclusions: Dic-EFc and Ace-EFc at low concentrations decreased breast cancer cell proliferation and invasiveness, mainly of MDA-MB-231 cells. The above supports the potential use of compounds from leaf extracts of F. crocata in neoadjuvant therapy to reduce the progression of breast cancer tumors, mainly triple-negative tumors.

7.
Cells ; 11(20)2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36291097

RESUMO

Excess body weight and obesity have become significant risk factors for cancer development. During obesity, adipose tissue alters its biological function, deregulating the secretion of bioactive factors such as hormones, cytokines, and adipokines that promote an inflammatory microenvironment conducive to carcinogenesis and tumor progression. Adipokines regulate tumor processes such as apoptosis, proliferation, migration, angiogenesis, and invasion. Additionally, it has been found that they can modulate autophagy, a process implicated in tumor suppression in healthy tissue and cancer progression in established tumors. Since the tumor-promoting role of autophagy has been well described, the process has been suggested as a therapeutic target in cancer. However, the effects of targeting autophagy might depend on the tumor type and microenvironmental conditions, where circulating adipokines could influence the role of autophagy in cancer. Here, we review recent evidence related to the role of adipokines in cancer cell autophagy in an effort to understand the tumor response in the context of obesity under the assumption of an autophagy-targeting treatment.


Assuntos
Adipocinas , Autofagia , Carcinogênese , Neoplasias , Obesidade , Humanos , Adipocinas/metabolismo , Carcinogênese/metabolismo , Citocinas/metabolismo , Neoplasias/etiologia , Neoplasias/metabolismo , Obesidade/complicações , Microambiente Tumoral
8.
Tissue Cell ; 76: 101814, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35526310

RESUMO

Breast cancer is the most frequent malignancy among women in developed countries and the main cause of death related to cancer in women worldwide. Extracellular vesicles (EVs) are vesicles with a variable size enclosed within a phospholipid bilayer that contain a variety of molecules with biological activity. Cancer cells release EVs that induce proliferation, escape from apoptosis, reprogramming energy metabolism, invasion and metastasis. In this study we studied whether EV fractions deprived of platelet EVs from breast cancer women (BC EVs) can mediate cell processes related with angiogenesis in human umbilical vein endothelial cells (HUVECs). Our findings demonstrate that BC EVs enhance migration, invasion and formation of new tubules in HUVECs, compared with EV fractions deprived of platelet EVs from healthy women (Ctrl EVs). In summary, we demonstrate, for the first time, that BC EVs induce cellular processes in HUVECs that participate in angiogenesis.


Assuntos
Neoplasias da Mama , Vesículas Extracelulares , Neoplasias da Mama/patologia , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/patologia , Feminino , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Neovascularização Patológica/patologia
9.
J Cell Commun Signal ; 16(4): 531-546, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34309795

RESUMO

Insulin-like growth factor-1 (IGF-1) plays an important role in function and development of the mammary gland. However, high levels of IGF-1 has been associated with an increased risk of breast cancer development. Epithelial-mesenchymal transition (EMT) is a process where epithelial cells lose their epithelial characteristics and acquire a mesenchymal phenotype, which is considered one of the most important mechanisms in cancer initiation and promotion of metastasis. Extracellular vesicles (EVs) are released into the extracellular space by different cell types, which mediate intercellular communication and play an important role in different physiological and pathological processes, such as cancer. In this study, we demonstrate that EVs from MDA-MB-231 breast cancer cells stimulated with IGF-1 (IGF-1 EVs) decrease the levels of E-cadherin, increase the expression of vimentin and N-cadherin and stimulate the secretion of metalloproteinase-9 in mammary non-tumorigenic epithelial cells MCF10A. IGF-1 EVs also induce the expression of Snail1, Twist1 and Sip1, which are transcription factors involved in EMT. Moreover, IGF-1 EVs induce activation of ERK1/2, Akt1 and Akt2, migration and invasion. In summary, we demonstrate, for the first time, that IGF-1 EVs induce an EMT process in mammary non-tumorigenic epithelial cells MCF10A.

10.
J Pers Med ; 11(12)2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34945799

RESUMO

One of the main microvascular complications presented in the Mexican population is diabetic retinopathy which affects 27.50% of individuals with type 2 diabetes. Therefore, the purpose of this study is to construct a predictive model to find out the risk factors of this complication. The dataset contained a total of 298 subjects, including clinical and paraclinical features. An analysis was constructed using machine learning techniques including Boruta as a feature selection method, and random forest as classification algorithm. The model was evaluated through a statistical test based on sensitivity, specificity, area under the curve (AUC), and receiving operating characteristic (ROC) curve. The results present significant values obtained by the model obtaining 69% of AUC. Moreover, a risk evaluation was incorporated to evaluate the impact of the predictors. The proposed method identifies creatinine, lipid treatment, glomerular filtration rate, waist hip ratio, total cholesterol, and high density lipoprotein as risk factors in Mexican subjects. The odds ratio increases by 3.5916 times for control patients which have high levels of cholesterol. It is possible to conclude that this proposed methodology is a preliminary computer-aided diagnosis tool for clinical decision-helping to identify the diagnosis of DR.

11.
Healthcare (Basel) ; 9(4)2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33917300

RESUMO

Diabetes incidence has been a problem, because according with the World Health Organization and the International Diabetes Federation, the number of people with this disease is increasing very fast all over the world. Diabetic treatment is important to prevent the development of several complications, also lipid profile monitoring is important. For that reason the aim of this work is the implementation of machine learning algorithms that are able to classify cases, that corresponds to patients diagnosed with diabetes that have diabetes treatment, and controls that refers to subjects who do not have diabetes treatment but some of them have diabetes, bases on lipids profile levels. Logistic regression, K-nearest neighbor, decision trees and random forest were implemented, all of them were evaluated with accuracy, sensitivity, specificity and AUC-ROC curve metrics. Artificial neural network obtain an acurracy of 0.685 and an AUC value of 0.750, logistic regression achieve an accuracy of 0.729 and an AUC value of 0.795, K-nearest neighbor gets an accuracy of 0.669 and an AUC value of 0.709, on the other hand, decision tree reached an accuracy pg 0.691 and a AUC value of 0.683, finally random forest achieve an accuracy of 0.704 and an AUC curve of 0.776. The performance of all models was statistically significant, but the best performance model for this problem corresponds to logistic regression.

12.
Med Oncol ; 38(4): 40, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33728516

RESUMO

Linoleic acid (LA) is the most abundant polyunsaturated fatty acid in occidental diets, which mediate a variety of processes in human breast cancer cells, including migration and invasion. Extracellular vesicles (EVs) are vesicles released from endosomes and plasma membrane that are composed of a variety of molecules, including proteins, nucleic acids and lipids. EVs from cancer cells promote processes related with cancer progression. In the present study, we demonstrate that treatment of MDA-MB-231 cells with EVs from MDA-MB-231 cells stimulated with LA (LA EVs) promote migration and invasion via Src activity. LA EVs induce activation of FAK via Src activity and of Src and Akt2. LA EVs also induce the assembly of focal adhesions and MMP-9 secretion. These findings demonstrate that LA EVs mediate an autocrine and/or paracrine Src/FAK signaling pathway to promote migration and invasion.


Assuntos
Movimento Celular/efeitos dos fármacos , Vesículas Extracelulares/metabolismo , Quinase 1 de Adesão Focal/metabolismo , Ácido Linoleico/farmacologia , Quinases da Família src/metabolismo , Linhagem Celular Tumoral , Vesículas Extracelulares/efeitos dos fármacos , Adesões Focais/efeitos dos fármacos , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
13.
Healthcare (Basel) ; 9(2)2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33535510

RESUMO

The prevalence of diabetes mellitus is increasing worldwide, causing health and economic implications. One of the principal microvascular complications of type 2 diabetes is Distal Symmetric Polyneuropathy (DSPN), affecting 42.6% of the population in Mexico. Therefore, the purpose of this study was to find out the predictors of this complication. The dataset contained a total number of 140 subjects, including clinical and paraclinical features. A multivariate analysis was constructed using Boruta as a feature selection method and Random Forest as a classification algorithm applying the strategy of K-Folds Cross Validation and Leave One Out Cross Validation. Then, the models were evaluated through a statistical analysis based on sensitivity, specificity, area under the curve (AUC) and receiving operating characteristic (ROC) curve. The results present significant values obtained by the model with this approach, presenting 67% of AUC with only three features as predictors. It is possible to conclude that this proposed methodology can classify patients with DSPN, obtaining a preliminary computer-aided diagnosis tool for the clinical area in helping to identify the diagnosis of DSPN.

14.
Prostaglandins Other Lipid Mediat ; 153: 106519, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33238201

RESUMO

Extracellular vesicles (EVs) are vesicles secreted by normal and malignant cells that are implicated in tumor progression. Linoleic acid (LA) is an essential polyunsaturated fatty acid that induces migration, invasion and an increase in phospholipase D activity in breast cancer cells. In this study, we determined whether stimulation of MDA-MB-231 breast cancer cells with LA induces the secretion of EVs, which can mediate cell processes related with angiogenesis in human umbilical vein endothelial cells (HUVECs). Our findings demonstrate that treatment of MDA-MB-231 cells with 90 µM LA for 48 h induce an increase in the number of EVs released. Moreover, EVs from MDA-MB-231 stimulated with 90 µM LA induce FAK and Src activation and migration via FAK and Src activity, whereas the secretion of these EVs is through FFAR1 and FFAR4 activation in HUVECs. The EVs from MDA-MB-231 cells treated with LA also increase proliferation, invasion, MMP-9 secretion, an increase of MMP-2 secretion and formation of new tubules in HUVECs. In summary, we demonstrate, for the first time, that treatment with LA induces the release of EVs from MDA-MB-231 cells that induce cellular processes involved with angiogenesis in HUVECs.


Assuntos
Células Endoteliais da Veia Umbilical Humana , Neoplasias da Mama , Humanos , Ácido Linoleico , Metaloproteinase 2 da Matriz
15.
Cells ; 8(10)2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31554180

RESUMO

Leptin is one of the main adipokines secreted in breast tissue. Leptin promotes epithelial-mesenchymal transition (EMT), cell migration and invasion in epithelial breast cells, leading to tumor progression. Although, the molecular mechanisms that underlie these events are not fully understood, the activation of different signaling pathways appears to be essential. In this sense, the effects of leptin on the activation of kinases like Src and FAK, which regulate signaling pathways that activate the EMT program, are not completely described. Therefore, we investigated the involvement of these kinases using an in vitro model for leptin-induced EMT process in the non-tumorigenic MCF10A cell line. To this end, MCF10A cells were stimulated with leptin, and Src and FAK activation was assessed. Specific events occurring during EMT were also evaluated in the presence or absence of the kinases' chemical inhibitors PP2 and PF-573228. For instance, we tested the expression and subcellular localization of the EMT-related transcription factors Twist and ß-catenin, by western blot and immunofluorescence. We also evaluated the secretion and activation of matrix metalloproteases (MMP-2 and MMP-9) by gelatin zymography. Invasiveness properties of leptin-stimulated cells were determined by invadopodia formation assays, and by the Transwell chamber method. Our results showed that leptin promotes EMT through Src and FAK activation, which leads to the secretion and activation of MMP-2 and MMP-9, invadopodia formation and cell invasion in MCF10A cells. In conclusion, our data suggest that leptin promotes an increase in the expression levels of Twist and ß-catenin, the secretion of MMP-2, MMP-9, the invadopodia formation and invasion in MCF10A cells in a Src and FAK-dependent manner.


Assuntos
Mama/patologia , Leptina/farmacologia , Proteínas Nucleares/metabolismo , Proteína 1 Relacionada a Twist/metabolismo , Regulação para Cima , beta Catenina/metabolismo , Mama/citologia , Mama/efeitos dos fármacos , Mama/metabolismo , Linhagem Celular , Movimento Celular , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal , Feminino , Quinase 1 de Adesão Focal/metabolismo , Humanos , Pirimidinas/farmacologia , Quinolonas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sulfonas/farmacologia , Quinases da Família src/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-30700010

RESUMO

Diabetes is a chronic and noncommunicable but preventable disease that is affecting the Mexican population at worrying levels, being the first place in prevalence worldwide. Early diabetes detection has become important to prevent other health conditions that involve low organ yield until the patient death. Based on this problem, this work proposes the architecture of an Artificial Neural Network (ANN) for the automated classification of healthy patients from diabetics patients. The analysis was performed used a set of 19 para-clinical features to determine the health status of the patients. The developed model was evaluated through a statistical analysis based on the calculation of the loss function, accuracy, area under the curve (AUC) and receiving operating characteristics (ROC) curve. The results obtained present statistically significant values, with accuracy of 0.94 and AUC values of 0.98. Based on these results, it is possible to conclude that the ANN implemented in this work can classify patients with presence of diabetes from controls with significant accuracy, presenting preliminary results for the development of a diagnostic tool that can be supportive for health specialists.


Assuntos
Diabetes Mellitus/diagnóstico , Redes Neurais de Computação , Adulto , Área Sob a Curva , Diagnóstico Precoce , Feminino , Nível de Saúde , Humanos , Masculino , México , Pessoa de Meia-Idade , Modelos Teóricos , Curva ROC
17.
Sensors (Basel) ; 17(11)2017 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-29160799

RESUMO

Human Activity Recognition (HAR) is one of the main subjects of study in the areas of computer vision and machine learning due to the great benefits that can be achieved. Examples of the study areas are: health prevention, security and surveillance, automotive research, and many others. The proposed approaches are carried out using machine learning techniques and present good results. However, it is difficult to observe how the descriptors of human activities are grouped. In order to obtain a better understanding of the the behavior of descriptors, it is important to improve the abilities to recognize the human activities. This paper proposes a novel approach for the HAR based on acoustic data and similarity networks. In this approach, we were able to characterize the sound of the activities and identify those activities looking for similarity in the sound pattern. We evaluated the similarity of the sounds considering mainly two features: the sound location and the materials that were used. As a result, the materials are a good reference classifying the human activities compared with the location.


Assuntos
Atividades Humanas , Acústica , Humanos , Reconhecimento Automatizado de Padrão , Processamento de Sinais Assistido por Computador , Som
18.
Ginecol Obstet Mex ; 83(8): 467-70, 2015 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-26591030

RESUMO

BACKGROUND: The absence of IUD visible threads in the cervix is a complication of the intrauterine device. The IUD withdrawal in these cases was performed with Novak cannula or curettage instrumented under anesthesia and surgery. Its extraction with Mathew clip is an alternative. OBJECTIVE: To demostrate the effectiveness of the Mathew's clip as an alternatively for removal of intrauterine devices not visible threads. MATERIAL AND METHODS: A cross-sectional, retrospective, descriptive study was conducted in from February 2012 to July 2014 at the Family Planning Service of Gynecology and Obstetrics of the General Hospital of Mexico "Dr. Eduardo Liceaga ". RESULTS: 106 patients (54%) had no visible threads; in 84 patients (81.5 %) it was removed with Novak, cannula; in 19 patients (18.4%) in which it was not possible, the removal was done with a Mathew's clip. DISCUSSION: Mathew' clip is an alternative in cases where it was not possible to remove the IUD with Novak cannula, 19 IUDs no visible threads were removed. CONCLUSIONS. Mathew clip for removal of intrauterine devices with no visible threads means less risk to the patient and a decrease in institutional costs.


Assuntos
Remoção de Dispositivo/instrumentação , Dispositivos Intrauterinos , Adolescente , Adulto , Estudos Transversais , Desenho de Equipamento , Serviços de Planejamento Familiar , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
19.
Ginecol Obstet Mex ; 82(8): 547-51, 2014 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-25282947

RESUMO

The risk of pregnancy in breastfeeding should be a concern of women. Family planning programs in the post natal period contraceptive choices offer high efficiency. Breastfeeding is a natural contraception method (LAM) as a contraceptive shield has 98% efficiency. Women should consider using an alternate contraceptive method when feeding requirements for this method to be effective are not met. Some of contraceptive alternatives in lactation include hormonal methods. According to the Medical Eligibility Criteria for Contraceptive Use WHO combined hormonal methods are contraindicated during breastfeeding, hormonal progestogen only methodo are considered only in Group 3 and Group 1 immediate postpartum after 6 weeks postpartum. There are modifications to these criteria by the CDC and the UK for the use of these hormones in early in lactation.


Assuntos
Intervalo entre Nascimentos , Aleitamento Materno , Anticoncepção/métodos , Feminino , Humanos
20.
Ginecol Obstet Mex ; 82(6): 389-93, 2014 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-25016898

RESUMO

The risk of pregnancy in breastfeeding should be a concern of women. Family planning programs in the postnatal period contraceptive choices offer high efficiency. Breastfeeding is a natural contraception method (LAM) as a contraceptive shield has 98 % efficiency. Women should consider using an alternate contraceptive method when feeding requirements for this method to be effective are not met. Some of contraceptive alternatives in lactation include hormonal methods. According to the Medical Eligibility Criteria for Contraceptive Use WHO combined hormonal methods are contraindicated during breast feeding, hormonal progestogen only method are considered only in Group 3 and Group 1 immediate postpartum after 6 weeks postpartum. There are modifications to these criteria by the CDC and the UK for the use of these hormones in early in lactation.


Assuntos
Aleitamento Materno , Anticoncepção/métodos , Lactação/fisiologia , Contraindicações , Serviços de Planejamento Familiar , Feminino , Humanos , Período Pós-Parto , Gravidez , Fatores de Tempo , Organização Mundial da Saúde
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