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2.
Cell Biol Int ; 48(5): 610-625, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38263584

RESUMEN

Fucosyltransferases (Fut) regulate the fucosylation process associated with tumorogenesis in different cancer types. Ascitic fluid (AF) from patients diagnosed with advanced stage of epithelial ovarian cancer (EOC) is considered as a dynamic tumor microenvironment associated with poor prognosis. Previous studies from our laboratory showed increased fucosylation in SKOV-3 and OVCAR-3, cancer-derived cell lines, when these cells were incubated with AFs derived from patients diagnosed with EOC. In the present work we studied three fucosyltransferases (Fut 2, Fut 4, and Fut 8) in SKOV-3, OVCAR-3 and CAOV-3 cell lines in combination with five different AFs from patients diagnosed with this disease, confirming that all tested AFs increased fucosylation. Then, we demonstrate that mRNAs of these three enzymes were overexpressed in the three cell lines under treatment with AFs. SKOV-3 showed the higher overexpression of Fut 2, Fut 4, and Fut 8 in comparison with the control condition. We further confirmed, in the SKOV-3 cell line, by endpoint PCR, WB, and confocal microscopy, that the three enzymes were overexpressed, being Fut 4 the most overexpressed enzyme compared to Fut 2 and Fut 8. These enzymes were concentrated in vesicular structures with a homogeneous distribution pattern throughout the cytoplasm. Moreover, we found that among the three enzymes, only Fut 4 was located inside the nuclei. The nuclear location of Fut 4 was confirmed for the three cell lines. These results allow to propose Fut 2, Fut 4, and Fut 8 as potential targets for EOC treatment or as diagnostic tools for this disease.


Asunto(s)
Neoplasias Ováricas , Humanos , Femenino , Neoplasias Ováricas/metabolismo , Carcinoma Epitelial de Ovario , Líquido Ascítico/metabolismo , Líquido Ascítico/patología , 60622 , Apoptosis , Línea Celular Tumoral , Fucosiltransferasas/genética , Fucosiltransferasas/metabolismo , Microambiente Tumoral
4.
Injury ; 54 Suppl 6: 110731, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37085352

RESUMEN

BACKGROUND: The COVID-19 epidemic generated major changes in general surgical management protocols. The literature has reported high mortality rates for hip fracture surgery in patients with COVID-19. This study describes the morbidity and mortality in patients undergoing surgery due to hip fractures in 12 Colombian institutions between March and September 2020. METHODOLOGY: This was a retrospective observational descriptive study. Medical records of 12 hospitals were reviewed. Consecutive patients who underwent hip fracture surgery from March 6 to September 6, 2020, were included. Data collected were sociodemographic profile, type of fracture, surgical treatment, complications, and early (1 month) or mid-term (1-6 months) mortality associated or not with COVID-19. RESULTS: Five hundred twenty patients with hip fractures requiring surgery in the 12 institutions were included. 364 (70%) were women; mean age was 77.7 years (SD: 13.8), mean BMI was 25.1, 91.73% of patients had at least one comorbidity, 60.38% were classified as ASA II and 25.77% as ASA III. There were 267 (51.34%) pertrochanteric fractures, 227 (43.65%) femoral neck fractures, and 26 (5.0%) subtrochanteric fractures. 274 (52.69%) patients were treated with osteosynthesis, 244 (46.92%) with arthroplasty, and 2 (0.38%) with girdlestone. Surgery was performed less than 24 h after the fracture for 115 (22.11%) patients, between 24 and 72 h for 208 (40.0%) patients, and more than 72 h for 197 (37.88%) patients. One hundred six patients in total suffered a medical or surgical complication throughout the different follow-up stages, amongst the most frequent were respiratory failure, coronary events, surgical site infection, cutting-out and peri­implant fracture. 25 (4.8%) patients required attention in the Intensive Care Unit (ICU). 13 patients had COVID-19 throughout the follow-up period. 27 patients died due to any cause, and 3 of them had reported a positive COVID-19 test any time during follow-up period, of which one died during the first month, and two died between 1 and 6 months. Statistically significant associations were found between age older than 75 years old, ASA classification, ICU requirement, and death. CONCLUSION: 520 patients received surgical treatment for hip fracture during the first six months of the COVID-19 pandemic in 12 medical centers in Colombia. 21.10% suffered a complication during the early stage (30 days) and 4.77% during the midterm stage (1-6 months). 4.8% were admitted in the ICU during the early stage. All-cause death was 27 patients, early death was 11 (40.74%) and midterm death was 16 (59.25%). 13 patients were positive for COVID-19, 3 died, one (1/5=20%) on the first 30 days and the other two (2/8=25%) from month 1 to 6.


Asunto(s)
Artroplastia de Reemplazo de Cadera , COVID-19 , Fracturas de Cadera , Anciano , Femenino , Humanos , Masculino , Artroplastia de Reemplazo de Cadera/efectos adversos , COVID-19/epidemiología , Fracturas de Cadera/epidemiología , Fracturas de Cadera/cirugía , Fracturas de Cadera/etiología , Morbilidad , Pandemias , Estudios Retrospectivos , Persona de Mediana Edad , Anciano de 80 o más Años
5.
Artículo en Inglés | MEDLINE | ID: mdl-36697230

RESUMEN

BACKGROUND AND OBJECTIVES: Myasthenia gravis (MG) is an autoimmune disease associated with comorbid thymoma in 10%-15% of cases. Cytotoxic T lymphocyte-associated antigen 4 (CTLA4) expressed by T cells downregulates T-cell-mediated immune response. Polymorphisms in the CTLA4 gene have been associated with the development of MG. In this context, we aimed to determine whether CTLA4 expression in the thymoma differs between patients with and without MG and whether CTLA4 gene polymorphisms are associated with these differences. METHODS: This is a retrospective study of all patients, with and without MG, surgically treated at our institution for thymoma between January 2010 and December 2020. Ten samples were obtained from normal thymuses as controls. The number of CTLA4-positive cells in paraffin-embedded thymoma samples was determined by immunohistochemistry. The presence of follicular-center and regulatory T-cell lymphocytes was determined by immunohistochemistry (B-cell lymphoma [BCL]-6 expression) and double immunofluorescence-based staining of CD4-FOXP3, respectively. We evaluated the association between thymic expression of CTLA4 and the development of MG. We also determined the association between CTLA4 expression and various clinical and prognostic characteristics of MG. We sequenced the CTLA4 gene and evaluated possible associations between CTLA4 polymorphisms and thymic CTLA4 expression. Finally, we assessed the potential association between these polymorphisms and the risk of MG. RESULTS: Forty-one patients with thymoma were included. Of them, 23 had comorbid MG (56.1%). On average, patients with MG had fewer CTLA4-positive cells in the thymoma than non-MG patients: 69.3 cells/mm2 (95% CIs: 39.6-99.1) vs 674.4 (276.0-1,024.0) cells/mm2; p = 0.001 and vs controls (200.74 [57.9-343.6] cells/mm2; p = 0.02). No between-group differences (MG vs non-MG) were observed in the number of cells positive for BCL6 or CD4-FOXP3. CTLA4 expression was not associated with differences in MG outcome or treatment refractoriness. Two polymorphisms were detected in the CTLA4 gene, rs231770 (n = 30 patients) and rs231775 (n = 17). MG was present in a similar proportion of patients for all genotypes. However, a nonsignificant trend toward a lower CTLA4-positive cell count was observed among carriers of the rs231775 polymorphism vs noncarriers: 77.9 cells/mm2 (95% CI: -51.5 to 207.5) vs 343.3 cells/mm2 (95% CI: 126.2-560.4). DISCUSSION: Reduced CTLA4 expression in thymoma may predispose to a higher risk of developing MG.


Asunto(s)
Miastenia Gravis , Timoma , Neoplasias del Timo , Humanos , Antígeno CTLA-4/genética , Estudios Retrospectivos , Neoplasias del Timo/complicaciones , Factores de Transcripción Forkhead/genética , Probabilidad
6.
Cir Esp (Engl Ed) ; 101(6): 408-416, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35671974

RESUMEN

OBJECTIVES: The objective of this study was to assess the diagnostic performance of combined computerised tomography (CT) and positron emission tomography (PET) in mediastinal staging of surgical lung cancer based on data obtained from the prospective cohort of the Spanish Group for Video-Assisted Thoracic Surgery (GEVATS). METHODS: A total of 2782 patients underwent surgery for primary lung carcinoma. We analysed diagnostic success in mediastinal lymph node staging (cN2) using CT and PET. Bivariate and multivariate analyses were performed of the factors involved in this success. The risk of unexpected pN2 disease was analysed for cases in which an invasive testing is recommended: cN1, the tumour centrally located or the tumour diameter >3 cm. RESULTS: The overall success of CT together with PET was 82.9% with a positive predictive value of 0.21 and negative predictive value of 0.93. If the tumour was larger than 3 cm and for each unit increase in mediastinal SUVmax, the probability of success was lower with OR 0.59 (0.44-0.79) and 0.71 (0.66-0.75), respectively. In the video-assisted thoracic surgery (VATS) approach, the probability of success was higher with OR 2.04 (1.52-2.73). The risk of unexpected pN2 increased with the risk factors cN1, the tumour centrally located or the tumour diameter >3 cm: from 4.5% (0 factors) to 18.8% (3 factors) but did not differ significantly as a function of whether invasive testing was performed. CONCLUSIONS: CT and PET together have a high negative predictive value. The overall success of the staging is lower in the case of tumours >3 cm and high mediastinal SUVmax, and it is higher when VATS is performed. The risk of unexpected pN2 is higher if the disease is cN1, the tumour centrally located or the tumour diameter >3 cm but does not vary significantly as a function of whether patients have undergone invasive testing.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Cirugía Torácica Asistida por Video , Estudios Prospectivos , Estadificación de Neoplasias , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Neoplasias Pulmonares/patología , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/cirugía , Ganglios Linfáticos/patología
7.
World J Clin Oncol ; 13(6): 429-447, 2022 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-35949427

RESUMEN

The treatment of small cell lung cancer (SCLC) is a challenge for all specialists involved. New treatments have been added to the therapeutic armamentarium in recent months, but efforts must continue to improve both survival and quality of life. Advances in surgery and radiotherapy have resulted in prolonged survival times and fewer complications, while more careful patient selection has led to increased staging accuracy. Developments in the field of systemic therapy have resulted in changes to clinical guidelines and the management of patients with advanced disease, mainly with the introduction of immunotherapy. In this article, we describe recent improvements in the management of patients with SCLC, review current treatments, and discuss future lines of research.

8.
World J Clin Oncol ; 13(4): 276-286, 2022 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-35582653

RESUMEN

The 2004 discovery of EGFR mutations, followed by ALK rearrangements, ushered in a targeted therapy era for advanced non-small cell lung cancer (NSCLC). Tyrosine kinase inhibitors targeting gene alterations have substantially improved survival and quality of life for patients with NSCLC. In the last decade, rearrangements of the ROS1 oncogene have been incorporated into healthcare practice that are applicable to another small subgroup of patients who benefit from similar targeted strategies. Recent genome studies of lung adenocarcinoma have identified other possible therapeutic targets, including RET, NTRK fusions, c-MET alterations, and activating mutations in KRAS, BRAF, and HER2, all with frequencies greater than 1%. Lung cancers harbouring these genome changes can potentially be treated with agents approved for other indications or under clinical development. This review updates the therapeutic arsenal that especially targets those genes.

9.
Cancer Cell Int ; 22(1): 6, 2022 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-34991589

RESUMEN

BACKGROUND: Ovarian cancer is the most aggressive gynecological malignancy. Transcriptional regulators impact the tumor phenotype and, consequently, clinical progression and response to therapy. PHD finger protein 20-like protein 1 (PHF20L1) is a transcriptional regulator with several isoforms, and studies on its role in ovarian cancer are limited. We previously reported that PHF20L1 is expressed as a fucosylated protein in SKOV-3 cells stimulated with ascites from patients with ovarian cancer. METHODS: We decided to analyze the expression of PHF20L1 in ovarian cancer tissues, determine whether a correlation exists between PHF20L1 expression and patient clinical data, and analyze whether ascites can modulate the different isoforms of this protein. Ovarian cancer biopsies from 29 different patients were analyzed by immunohistochemistry, and the expression of the isoforms in ovarian cancer cells with or without exposure to the tumor microenvironment, i.e., the ascitic fluid, was determined by western blotting assays. RESULTS: Immunohistochemical results suggest that PHF20L1 exhibits increased expression in sections of tumor tissues from patients with ovarian cancer and that higher PHF20L1 expression correlates with shorter progression-free survival and shorter overall survival. Furthermore, western blotting assays determined that protein isoforms are differentially regulated in SKOV-3 cells in response to stimulation with ascites from patients with epithelial ovarian cancer. CONCLUSION: The results suggest that PHF20L1 could play a relevant role in ovarian cancer given that higher PHF20L1 protein expression is associated with lower overall patient survival.

10.
BMJ Open ; 12(12): e063778, 2022 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-36600389

RESUMEN

INTRODUCTION: Myocardial injury after non-cardiac surgery has been defined as myocardial injury due to ischaemia, with or without additional symptoms or ECG changes occurring during or within 30 days after non-cardiac surgery and mainly diagnosed based on elevated postoperative cardiac troponin (cTn) values. In patients undergoing thoracic surgery for lung resection, only postoperative cTn elevations are seemingly not enough as an independent predictor of cardiovascular complications. After lung resection, troponin elevations may be regulated by mechanisms other than myocardial ischaemia. The combination of perioperative natriuretic peptide measurement together with high-sensitivity cTns may help to identify changes in ventricular function during thoracic surgery. Integrating both cardiac biomarkers may improve the predictive value for cardiovascular complications after lung resection. We designed our cohort study to evaluate perioperative elevation of both high-sensitivity troponin I (hs-TnI) and N-terminal pro-brain natriuretic peptide (NT-proBNP) in patients undergoing lung resection and to establish a risk score for major cardiovascular postoperative complications. METHODS AND ANALYSIS: We will conduct a prospective, multicentre, observational cohort study, including 345 patients undergoing elective thoracic surgery for lung resection. Cardiac biomarkers such as hs-TnI and NT-proBNP will be measured preoperatively and at postoperatively on days 1 and 2. We will calculate a risk score for major cardiovascular postoperative complications based on both biomarkers' perioperative changes. All patients will be followed up for 30 days after surgery. ETHICS AND DISSEMINATION: All participating centres were approved by the Ethics Research Committee. Written informed consent is required for all patients before inclusion. Results will be disseminated through publication in peer-reviewed journals and presentations at national or international conference meetings. TRIAL REGISTRATION NUMBER: NCT04749212.


Asunto(s)
Cardiopatías , Troponina I , Humanos , Biomarcadores , Relevancia Clínica , Estudios de Cohortes , Cardiopatías/etiología , Incidencia , Pulmón , Péptido Natriurético Encefálico , Estudios Observacionales como Asunto , Fragmentos de Péptidos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/diagnóstico , Valor Predictivo de las Pruebas , Estudios Prospectivos , Troponina T
11.
Eur J Neurol ; 28(6): 2083-2091, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33721382

RESUMEN

BACKGROUND AND PURPOSE: Prognosis of myasthenia gravis (MG) in patients with thymoma is not well established. Moreover, it is not clear whether thymoma recurrence or unresectable lesions entail a worse prognosis of MG. METHODS: This multicenter study was based on data from a Spanish neurologist-driven MG registry. All patients were aged >18 years at onset and had anti-acetylcholine receptor antibodies. We compared the clinical data of thymomatous and nonthymomatous patients. Prognosis of patients with recurrent or nonresectable thymomas was assessed. RESULTS: We included 964 patients from 15 hospitals; 148 (15.4%) had thymoma-associated MG. Median follow-up time was 4.6 years. At onset, thymoma-associated MG patients were younger (52.0 vs. 60.4 years, p < 0.001), had more generalized symptoms (odds ratio [OR]: 3.02, 95% confidence interval [CI]: 1.95-4.68, p < 0.001) and more severe clinical forms according to the Myasthenia Gravis Foundation of America (MGFA) scale (OR: 1.6, 95% CI: 1.15-2.21, p = 0.005). Disease severity based on MGFA postintervention status (MGFA-PIS) was higher in thymomatous patients at 1 year, 5 years, and the end of follow-up. Treatment refractoriness and mortality were also higher (OR: 2.28, 95% CI: 1.43-3.63, p = 0.001; hazard ratio: 2.46, 95% CI: 1.47-4.14, p = 0.001). Myasthenic symptoms worsened in 13 of 27 patients with recurrences, but differences in long-term severity were not significant. Fifteen thymomatous patients had nonresectable thymomas with worse MGFA-PIS and higher mortality at the end of follow-up. CONCLUSIONS: Thymoma-associated MG patients had more severe myasthenic symptoms and worse prognosis. Thymoma recurrence was frequently associated with transient worsening of MG, but long-term prognosis did not differ from nonrecurrent thymoma. Patients with nonresectable thymoma tended to present severe forms of MG.


Asunto(s)
Miastenia Gravis , Timoma , Neoplasias del Timo , Humanos , Miastenia Gravis/complicaciones , Miastenia Gravis/epidemiología , Recurrencia Local de Neoplasia , Estudios Retrospectivos , Timectomía , Timoma/complicaciones , Timoma/epidemiología , Neoplasias del Timo/complicaciones , Neoplasias del Timo/epidemiología
12.
Sensors (Basel) ; 22(1)2021 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-35009753

RESUMEN

This work presents a hybrid visual-based SLAM architecture that aims to take advantage of the strengths of each of the two main methodologies currently available for implementing visual-based SLAM systems, while at the same time minimizing some of their drawbacks. The main idea is to implement a local SLAM process using a filter-based technique, and enable the tasks of building and maintaining a consistent global map of the environment, including the loop closure problem, to use the processes implemented using optimization-based techniques. Different variants of visual-based SLAM systems can be implemented using the proposed architecture. This work also presents the implementation case of a full monocular-based SLAM system for unmanned aerial vehicles that integrates additional sensory inputs. Experiments using real data obtained from the sensors of a quadrotor are presented to validate the feasibility of the proposed approach.


Asunto(s)
Algoritmos , Robótica , Dispositivos Aéreos No Tripulados
13.
Sensors (Basel) ; 20(12)2020 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-32580347

RESUMEN

To obtain autonomy in applications that involve Unmanned Aerial Vehicles (UAVs), the capacity of self-location and perception of the operational environment is a fundamental requirement. To this effect, GPS represents the typical solution for determining the position of a UAV operating in outdoor and open environments. On the other hand, GPS cannot be a reliable solution for a different kind of environments like cluttered and indoor ones. In this scenario, a good alternative is represented by the monocular SLAM (Simultaneous Localization and Mapping) methods. A monocular SLAM system allows a UAV to operate in a priori unknown environment using an onboard camera to simultaneously build a map of its surroundings while at the same time locates itself respect to this map. So, given the problem of an aerial robot that must follow a free-moving cooperative target in a GPS denied environment, this work presents a monocular-based SLAM approach for cooperative UAV-Target systems that addresses the state estimation problem of (i) the UAV position and velocity, (ii) the target position and velocity, (iii) the landmarks positions (map). The proposed monocular SLAM system incorporates altitude measurements obtained from an altimeter. In this case, an observability analysis is carried out to show that the observability properties of the system are improved by incorporating altitude measurements. Furthermore, a novel technique to estimate the approximate depth of the new visual landmarks is proposed, which takes advantage of the cooperative target. Additionally, a control system is proposed for maintaining a stable flight formation of the UAV with respect to the target. In this case, the stability of control laws is proved using the Lyapunov theory. The experimental results obtained from real data as well as the results obtained from computer simulations show that the proposed scheme can provide good performance.

16.
Cancer Microenviron ; 12(2-3): 181-195, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31267484

RESUMEN

Ovarian cancer is considered to be the most lethal type of gynecological cancer. During the advanced stages of ovarian cancer, an accumulation of ascites is observed. Fucosylation has been classified as an abnormal post-translational modification that is present in many diseases, including ovarian cancer. Ovarian cancer cells that are cultured with ascites stimulation change their morphology; concomitantly, the fucosylation process is altered. However, it is not known which fucosylated proteins are modified. The goal of this work was to identify the differentially fucosylated proteins that are expressed by ovarian cancer cell lines that are cultured with ovarian cancer patients' ascites. Aleuria aurantia lectin was used to detect fucosylation, and some changes were observed, especially in the cell membrane. Affinity chromatography and mass spectrometry (MALDI-TOF) were used to identify 6 fucosylated proteins. Four proteins (Intermediate filament family orphan 1 [IFFO1], PHD finger protein 20-like protein 1 [PHF20L1], immunoglobulin gamma 1 heavy chain variable region partial [IGHV1-2], and Zinc finger protein 224 [ZNF224]) were obtained from cell cultures stimulated with ascites, and the other two proteins (Peregrin [BRPF1] and Dystrobrevin alpha [DTNA]) were obtained under normal culture conditions. The fucosylated state of some of these proteins was further analyzed. The experimental results show that the ascites of ovarian cancer patients modulated the fucosylation process. The PHD finger protein 20-like protein 1, Zinc finger protein 224 and Peregrin proteins colocalize with fucosylation at different levels.

17.
BMC Complement Altern Med ; 19(1): 153, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31262287

RESUMEN

BACKGROUND: Rhus trilobata Nutt. (Anacardiaceae) (RHTR) is a plant of Mexico that is traditionally used as an alternative treatment for several types of cancer. However, the phytochemical composition and potential toxicity of this plant have not been evaluated to support its therapeutic use. Therefore, this study aimed to evaluate the biological activity of RHTR against colorectal adenocarcinoma cells, determine its possible acute toxicity, and analyze its phytochemical composition. METHODS: The traditional preparation was performed by decoction of stems in distilled water (aqueous extract, AE), and flavonoids were concentrated with C18-cartridges and ethyl acetate (flavonoid fraction, FF). The biological activity was evaluated by MTT viability curves and the TUNEL assay in colorectal adenocarcinoma (CACO-2), ovarian epithelium (CHO-K1) and lung/bronchus epithelium (BEAS-2B) cells. The toxicological effect was determined in female BALB/c mice after 24 h and 14 days of intraperitoneal administration of 200 mg/kg AE and FF, respectively. Later, the animals were sacrificed for histopathological observation of organs and sera obtained by retro-orbital bleeding for biochemical marker analysis. Finally, the phytochemical characterization of AE and FF was conducted by UPLC-MSE. RESULTS: In the MTT assays, AE and FF at 5 and 18 µg/mL decreased the viability of CACO-2 cells compared with cells treated with vehicle or normal cells (p ≤ 0.05, ANOVA), with changes in cell morphology and the induction of apoptosis. Anatomical and histological analysis of organs did not reveal important pathological lesions at the time of assessment. Additionally, biochemical markers remained normal and showed no differences from those of the control group after 24 h and 14 days of treatment (p ≤ 0.05, ANOVA). Finally, UPLC-MSE analysis revealed 173 compounds in AE-RHTR, primarily flavonoids, fatty acids and phenolic acids. The most abundant compounds in AE and FF were quercetin and myricetin derivates (glycosides), methyl gallate, epigallocatechin-3-cinnamate, ß-PGG, fisetin and margaric acid, which might be related to the anticancer properties of RHTR. CONCLUSION: RHTR exhibits biological activity against cancer cells and does not present adverse toxicological effects during its in vivo administration, supporting its traditional use.


Asunto(s)
Antineoplásicos Fitogénicos/análisis , Rhus/química , Animales , Antioxidantes/análisis , Células CHO , Células CACO-2 , Cricetulus , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Flavonoides/análisis , Humanos , Medicina Tradicional , México , Ratones Endogámicos BALB C , Fitoterapia , Extractos Vegetales/análisis , Extractos Vegetales/uso terapéutico , Extractos Vegetales/toxicidad , Polifenoles/análisis , Rhus/toxicidad
18.
Sensors (Basel) ; 18(12)2018 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-30513949

RESUMEN

In this work, the problem of the cooperative visual-based SLAM for the class of multi-UA systems that integrates a lead agent has been addressed. In these kinds of systems, a team of aerial robots flying in formation must follow a dynamic lead agent, which can be another aerial robot, vehicle or even a human. A fundamental problem that must be addressed for these kinds of systems has to do with the estimation of the states of the aerial robots as well as the state of the lead agent. In this work, the use of a cooperative visual-based SLAM approach is studied in order to solve the above problem. In this case, three different system configurations are proposed and investigated by means of an intensive nonlinear observability analysis. In addition, a high-level control scheme is proposed that allows to control the formation of the UAVs with respect to the lead agent. In this work, several theoretical results are obtained, together with an extensive set of computer simulations which are presented in order to numerically validate the proposal and to show that it can perform well under different circumstances (e.g., GPS-challenging environments). That is, the proposed method is able to operate robustly under many conditions providing a good position estimation of the aerial vehicles and the lead agent as well.

19.
Sensors (Basel) ; 18(5)2018 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-29701722

RESUMEN

This work presents a cooperative monocular-based SLAM approach for multi-UAV systems that can operate in GPS-denied environments. The main contribution of the work is to show that, using visual information obtained from monocular cameras mounted onboard aerial vehicles flying in formation, the observability properties of the whole system are improved. This fact is especially notorious when compared with other related visual SLAM configurations. In order to improve the observability properties, some measurements of the relative distance between the UAVs are included in the system. These relative distances are also obtained from visual information. The proposed approach is theoretically validated by means of a nonlinear observability analysis. Furthermore, an extensive set of computer simulations is presented in order to validate the proposed approach. The numerical simulation results show that the proposed system is able to provide a good position and orientation estimation of the aerial vehicles flying in formation.

20.
Rev. colomb. ortop. traumatol ; 32(3): 161-166, 2018. ilus.
Artículo en Español | LILACS, COLNAL | ID: biblio-1373443

RESUMEN

Introducción Las copas de doble movilidad son implantes en que se introduce una cabeza protésica en un núcleo de polietileno, el cual posteriormente se articula con una copa metálica implantada en el acetábulo. Este tipo de diseño desarrollado en Francia desde la década de 1970ha demostrado disminuir el riesgo de luxación en un remplazo total de cadera. Estas copas han sido utilizadas históricamente de forma no cementada. No obstante, actualmente se pueden utilizar copas cementadas. Los objetivos de este estudio son determinar la sobrevida de las copas de doble movilidad cementadas y medir la calidad de vida de los pacientes. Materiales y métodos Se realiza un estudio multicéntrico retrospectivo, cuya indicación para la cirugía sea fracturas (61,5%), artrosis (34,6%) o tumores (3,8%). El análisis se realizó con los pacientes operados entre los años 2011-2013 y se encontraron 82 caderas operadas con copas de doble movilidad cementadas con un promedio de edad de 76 años. Resultados Se revisó una copa de doble movilidad por infección; por tanto, se obtuvo una sobrevida del 97,6% con un promedio de tiempo de seguimiento de 33,7 (29,7-37,7) meses con un IC 95%, y un promedio en la escala de Oxford de 38,2 (34,8-41,7) con un IC 95%. Discusión Se pudo concluir que la tasa de sobrevida es óptima para el tiempo de seguimiento y el puntaje promedio en la escala de Oxford es bueno si se tienen en cuenta las comorbilidades y la media de edad de los pacientes. Nivel de evidencia clínica. Nivel IV.


Background The dual mobility cups are implants where a prosthetic head is introduced into a polyethylene core, which is subsequently articulated with a metal cup to be implanted in the acetabulum. This type of design developed in France since the seventies has shown to decrease the risk of dislocation in total hip replacement. These cups have been used historically cementless, however now can be use cemented. The objectives are to determine the survival of double cemented mobility cups and to measure the quality of life of patients. Materials and methods A retrospective multicenter study was made. Patients who underwent primary surgery and whose indication for surgery is fractures (61.5%), osteoarthritis (34.6%) or tumors (3.8%) were included. The analysis was performed with patients operated between 2011 and 2013. Results The study was based in 82 hips operated with dual mobility cemented cups with a patient's average age of 76 (13.4) years old. A dual mobility cup was checked for infection therefore obtaining a survival rate of 97.6% and an average follow up of 33.7 months with 95% CI (29,7-37,7) and an average in the Oxford scale of 38.2 with 95% CI (34,8-41,7) Discussion It was concluded that the survival rate is optimal taking into account the follow up time and the average score on Oxford scale were good considering comorbidities and the average age of patients. Evidence level. IV.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Osteoartritis , Calidad de Vida , Fracturas Óseas , Prótesis de Cadera
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