5,145 research outputs found
A Comparative Study of Some Markov Random Fields and Different Criteria Optimization in Image Restoration
The present chapter illustrates the use of some recent alternative methods to deal with digital image filtering and restoration. This collection of methods is inspired on the use of Markov Random Fields (MRF), which introduces prior knowledge of information that will allow, more efficiently, modeling the image acquisition process. The methods based on the MRF are analyzed and proposed into a Bayesian framework and their principal objective is to eliminate noise and some effects caused by excessive smoothness on the reconstruction process of images which are rich in contours or edges. In order to preserve object edges into the image, the use of certain convexity criteria into the MRF is proposed obtaining adequate weighting of cost functions in cases where discontinuities are remarked and, even better, for cases where such discontinuities are very smooth
Alguns caràcters del margall (lolium multiflorum var. westerwoldicum) correlacionats amb la producció
Peer Reviewe
Alguns caràcters del margall (Lolium multiflorum var. westerwoldicum). Correlacionats amb la producció
Peer Reviewe
Impact of chlorogenic acids from coffee on urine metabolome in healthy human subjects
Several studies suggest that coffee has some benefits for health; however, little is known about the specific role of the main polyphenol compounds of coffee, chlorogenic acids (CGAs), without caffeine interaction. A 1H-Nuclear Magnetic Resonance (1H-NMR)-based metabolomics approach was used to assess the effect of CGAs from coffee on the human urine metabolome. Ten male volunteers participated in a dietary crossover randomized intervention study with a rich CGAs coffee extract beverage (CEB: 223 mg/100 ml of CGAs). The study consisted of a daily intake of CEB or a control beverage with equal caffeine dose during 28 days. Fasting urines collected at the first and last days of each period of the study were analyzed using an CGAs untargeted 1H-NMR approach. Additionally, 4-hour postpandrial urines after the first intake of each beverage were also analyzed. Uni- and multi-variate statistic approaches were used to strengthen the results. Multilevel partial least squares discriminant analysis (ML-PLS-DA) was used to paired comparisons across the crossover design. A further univariate analysis model for crossover studies was performed to assess the significant changes. Acute consumption of CEB resulted in high excretion of 2-furoylglycine, likewise endogenous compounds such as succinic, citric, 3-methyl-2-oxovaleric and isobutyric acids. Sustained consumption of CEB showed an increase of microbiota-derived compounds such as hippuric, 3-(3-Hydroxyphenyl)-3-hydroxypropionic and 3-hydroxyhippuric acids in urine. Moreover, trigonelline was found in urine after both acute and sustained intakes, as well as in the composition of the beverage exhibiting a direct excretion of this biomarker without any biotransformation, suggesting a non-interindividual variation
In vitro culture with gemcitabine augments death receptor and NKG2D ligand expression on tumour cells
Much effort has been made to try to understand the relationship between chemotherapeutic treatment of cancer and the immune system. Whereas much of that focus has been on the direct effect of chemotherapy drugs on immune cells and the release of antigens and danger signals by malignant cells killed by chemotherapy, the effect of chemotherapy on cells surviving treatment has often been overlooked. In the present study, tumour cell lines: A549 (lung), HCT116 (colon) and MCF-7 (breast), were treated with various concentrations of the chemotherapeutic drugs cyclophosphamide, gemcitabine (GEM) and oxaliplatin (OXP) for 24 hours in vitro. In line with other reports, GEM and OXP upregulated expression of the death receptor CD95 (fas) on live cells even at sub-cytotoxic concentrations. Further investigation revealed that the increase in CD95 in response to GEM sensitised the cells to fas ligand treatment, was associated with increased phosphorylation of stress activated protein kinase/c-Jun N-terminal kinase and that other death receptors and activatory immune receptors were co-ordinately upregulated with CD95 in certain cell lines. The upregulation of death receptors and NKG2D ligands together on cells after chemotherapy suggest that although the cells have survived preliminary treatment with chemotherapy they may now be more susceptible to immune cell-mediated challenge. This re-enforces the idea that chemotherapy-immunotherapy combinations may be useful clinically and has implications for the make-up and scheduling of such treatments
Effect of Mono and Di-rhamnolipids on Biofilms Pre-formed by Bacillus subtilis BBK006.
Different microbial inhibition strategies based on the planktonic bacterial physiology have been known to have limited efficacy on the growth of biofilms communities. This problem can be exacerbated by the emergence of increasingly resistant clinical strains. Biosurfactants have merited renewed interest in both clinical and hygienic sectors due to their potential to disperse microbial biofilms. In this work, we explore the aspects of Bacillus subtilis BBK006 biofilms and examine the contribution of biologically derived surface-active agents (rhamnolipids) to the disruption or inhibition of microbial biofilms produced by Bacillus subtilis BBK006. The ability of mono-rhamnolipids (Rha-C10-C10) produced by Pseudomonas aeruginosa ATCC 9027 and the di-rhamnolipids (Rha-Rha-C14-C14) produced by Burkholderia thailandensis E264, and phosphate-buffered saline to disrupt biofilm of Bacillus subtilis BBK006 was evaluated. The biofilm produced by Bacillus subtilis BBK006 was more sensitive to the di-rhamnolipids (0.4 g/L) produced by Burkholderia thailandensis than the mono-rhamnolipids (0.4 g/L) produced by Pseudomonas aeruginosa ATCC 9027. Rhamnolipids are biologically produced compounds safe for human use. This makes them ideal candidates for use in new generations of bacterial dispersal agents and useful for use as adjuvants for existing microbial suppression or eradication strategies
Gestión de la Innovación en Equipos Multidisciplinarios: Rol del Liderazgo en la Colaboración Exitosa
This summary examines the management of innovation in multidisciplinary teams with a focus on the role of leadership in successful collaboration in Higher Education Institutions (HEIs) in the State of Mexico. The objective is to investigate how leadership impacts effective collaboration and the generation of innovation in multidisciplinary academic environments. The methodology is based on documentary analysis, surveys and interviews with team members and leaders in HEIs. The results indicate that goal-oriented and participatory leadership is essential to foster synergy between disciplines, promote communication and trust, and facilitate the generation of innovative ideas in multidisciplinary teams. Likewise, the importance of training and training leaders to develop interdisciplinary management skills is highlighted. These findings provide valuable information to improve innovation management in HEIs and optimize collaboration in multidisciplinary teams in the State of Mexico.Este resumen examina la gestión de la innovación en equipos multidisciplinarios con un enfoque en el papel del liderazgo en la colaboración exitosa en Instituciones de Educación Superior (IES) en el Estado de México. El objetivo es investigar cómo el liderazgo impacta en la colaboración efectiva y la generación de innovación en entornos académicos multidisciplinarios. La metodología se basa en análisis documental, encuestas y entrevistas a miembros de equipos y líderes en IES. Los resultados indican que un liderazgo participativo y orientado a metas es esencial para fomentar la sinergia entre disciplinas, promover la comunicación y la confianza, y facilitar la generación de ideas innovadoras en equipos multidisciplinarios. Asimismo, se destaca la importancia de la formación y capacitación de líderes para desarrollar habilidades de gestión interdisciplinaria. Estos hallazgos proporcionan información valiosa para mejorar la gestión de la innovación en IES y optimizar la colaboración en equipos multidisciplinarios en el Estado de México
HPV infection and immunochemical detection of cell-cycle markers in verrucous carcinoma of the penis
Penile verrucous carcinoma is a rare disease and little is known of its aetiology or pathogenesis. In this study we examined cell-cycle proteins expression and correlation with human papillomavirus infection in a series of 15 pure penile verrucous carcinomas from a single centre. Of 148 penile tumours, 15 (10%) were diagnosed as pure verrucous carcinomas. The expression of the cell-cycle-associated proteins p53, p21, RB, p16INK4A and Ki67 were examined by immunohistochemistry. Human papillomavirus infection was determined by polymerase chain reaction to identify a wide range of virus types. The expression of p16INK4A and Ki67 was significantly lower in verrucous carcinoma than in usual type squamous cell carcinoma, whereas the expression of p53, p21 and RB was not significantly different. p53 showed basal expression in contrast to usual type squamous cell carcinoma. Human papillomavirus infection was present in only 3 out of 13 verrucous carcinomas. Unique low-risk, high-risk and mixed viral infections were observed in each of the three cases. In conclusion, lower levels of p16INK4A and Ki67 expressions differentiate penile verrucous carcinoma from usual type squamous cell carcinoma. The low Ki67 index reflects the slow-growing nature of verrucous tumours. The low level of p16INK4A expression and human papillomavirus detection suggests that penile verrucous carcinoma pathogenesis is unrelated to human papillomavirus infection and the oncogenes and tumour suppressor genes classically altered by virus infection.Peer reviewedFinal Accepted Versio
N-terminal Pro B-type Natriuretic Peptide and the Evaluation of Cardiac Dysfunction and Severity of Disease in Cirrhotic Patients
Purpose: Cardiac dysfunction and hyperdynamic systemic circulation may be present in patients with cirrhosis. The purpose of this study was to identify relations between plasma levels of N-terminal-proBNP (NT-proBNP), reflecting early ventricular dysfunction, and the severity of liver disease and cardiac dysfunction in cirrhotic patients. Materials and Methods: Sixty-three cirrhotic patients and 15 controls (group 1) were enrolled in this study. Plasma levels of NT-proBNP were determined in echocardiographically examined patients, which were allocated to 1 of 3 groups according to Child-Pugh classification or into 2 groups, i.e., a compensated group without ascites (group 2) and decompensated group with ascites (group 3). Results: Plasma NT-proBNP levels were significantly higher in cirrhotic patients (groups 2 and 3) than in age-matched controls (155.9 and 198.3 vs. 40.3 pg/mL
Consensus-Based Technical Recommendations for Clinical Translation of Renal Phase Contrast MRI
BACKGROUND:
Phase-contrast (PC) MRI is a feasible and valid noninvasive technique to measure renal artery blood flow, showing potential to support diagnosis and monitoring of renal diseases. However, the variability in measured renal blood flow values across studies is large, most likely due to differences in PC-MRI acquisition and processing. Standardized acquisition and processing protocols are therefore needed to minimize this variability and maximize the potential of renal PC-MRI as a clinically useful tool.
PURPOSE:
To build technical recommendations for the acquisition, processing, and analysis of renal 2D PC-MRI data in human subjects to promote standardization of renal blood flow measurements and facilitate the comparability of results across scanners and in multicenter clinical studies.
STUDY TYPE:
Systematic consensus process using a modified Delphi method.
POPULATION:
Not applicable.
SEQUENCE FIELD/STRENGTH:
Renal fast gradient echo-based 2D PC-MRI.
ASSESSMENT:
An international panel of 27 experts from Europe, the USA, Australia, and Japan with 6 (interquartile range 4–10) years of experience in 2D PC-MRI formulated consensus statements on renal 2D PC-MRI in two rounds of surveys. Starting from a recently published systematic review article, literature-based and data-driven statements regarding patient preparation, hardware, acquisition protocol, analysis steps, and data reporting were formulated.
STATISTICAL TESTS:
Consensus was defined as ≥75% unanimity in response, and a clear preference was defined as 60–74% agreement among the experts.
RESULTS:
Among 60 statements, 57 (95%) achieved consensus after the second-round survey, while the remaining three showed a clear preference. Consensus statements resulted in specific recommendations for subject preparation, 2D renal PC-MRI data acquisition, processing, and reporting.
DATA CONCLUSION:
These recommendations might promote a widespread adoption of renal PC-MRI, and may help foster the set-up of multicenter studies aimed at defining reference values and building larger and more definitive evidence, and will facilitate clinical translation of PC-MRI.
LEVEL OF EVIDENCE:
1
TECHNICAL EFFICACY STAGE:
- …