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1.
Int J Toxicol ; 43(3): 243-252, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38183303

RESUMEN

This work investigated the safety of extracts obtained from plants growing in Colombia, which have previously shown UV-filter/antigenotoxic properties. The compounds in plant extracts obtained by the supercritical fluid (CO2) extraction method were identified using gas chromatography coupled to mass spectrometry (GC/MS) analysis. Cytotoxicity measured as cytotoxic concentration 50% (CC50) and genotoxicity of the plant extracts and some compounds were studied in human fibroblasts using the trypan blue exclusion assay and the Comet assay, respectively. The extracts from Pipper eriopodon and Salvia aratocensis species and the compound trans-ß-caryophyllene were clearly cytotoxic to human fibroblasts. Conversely, Achyrocline satureioides, Chromolaena pellia, and Lippia origanoides extracts were relatively less cytotoxic with CC50 values of 173, 184, and 89 µg/mL, respectively. The C. pellia and L. origanoides extracts produced some degree of DNA breaks at cytotoxic concentrations. The cytotoxicity of the studied compounds was as follows, with lower CC50 values representing the most cytotoxic compounds: resveratrol (91 µM) > pinocembrin (144 µM) > quercetin (222 µM) > titanium dioxide (704 µM). Quercetin was unique among the compounds assayed in being genotoxic to human fibroblasts. Our work indicates that phytochemicals can be cytotoxic and genotoxic, demonstrating the need to establish safe concentrations of these extracts for their potential use in cosmetics.


Asunto(s)
Supervivencia Celular , Fibroblastos , Extractos Vegetales , Protectores Solares , Humanos , Protectores Solares/toxicidad , Protectores Solares/química , Extractos Vegetales/toxicidad , Extractos Vegetales/química , Fibroblastos/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayo Cometa , Salvia/química , Daño del ADN/efectos de los fármacos , Células Cultivadas , Lippia/química , Cromatografía de Gases y Espectrometría de Masas
2.
J Aging Phys Act ; : 1-9, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39089679

RESUMEN

BACKGROUND: Executive function (EF) deficits are a significant risk factor for falls among older adults (OAs). However, relationship between EF subdomains (shifting, updating, and inhibition), postural balance (PB), and fall risk in healthy OAs, remains poorly understood. OBJECTIVE: This study aimed to investigate the relationship between EF subdomains (shifting, updating, and inhibition) and PB, and to assess their impact on risk of falls in community-dwelling OAs. METHODS: A cross-sectional study involving 50 OAs aged over 60 years (average age of 72 years) was conducted. Participants underwent assessments of EF subdomains and PB using validated tests. A correlation analysis was employed to examine the relationships between EF and PB. RESULTS: The study revealed significant correlations between subdomains and PB. Mental set shifting (r = -.539; p < .001) and inhibition (r = -.395; p = .050) exhibited inverse relationships with PB. Stepwise multiple linear regression showed that Trail Making Test Part B was associated with the PB (R2 = .42, p < .001). CONCLUSION: These findings highlight the importance of assessing EF subdomains, particularly shifting and inhibition, to identify risk of falls. Trail Making Test Part B largely explains the variability of the PB. Integrating PB assessments and EF training, such as the Mini-BESTest, into routine care can be vital for fall prevention strategies. Significance/Implications: This knowledge underscores the need for cognitive training interventions focusing on shifting and inhibition to enhance PB and potentially reduce falls. Additionally, incorporation of EF assessment tools as Trail Making Test Part B and the Mini-BESTest into routine clinical practice for community-dwelling OAs is recommended to address fall prevention strategies.

3.
Neurourol Urodyn ; 42(1): 49-55, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36183388

RESUMEN

BACKGROUND: d-mannose is used as preventive measure against recurrent urinary tract infections (RUTIs). We studied d-mannosuria after a challenge test to identify favorable responders that could be targeted for long-term preventive therapy. MATERIAL AND METHODS: Following institutional review board approval, women attending a specialized tertiary care center urology clinic with a history of RUTIs were invited to participate by providing a urine sample (baseline), followed by the intake of home-dose d-mannose, and a second urine sample 1 h later (post). Urine samples were processed according to a d-mannosuria assay technique reported previously by our group. d-mannose concentrations were normalized to urinary creatinine. RESULTS: From July 2020 to March 2021, 26 patients met study criteria. Thirteen had a lower or unchanged ratio of baseline to post d-mannose, whereas 13 were responders. Among 19 taking 2 g, 12 had a lower or unchanged trend and 7 were responders with >20% increase in the d-mannose/creatinine ratio. Comparison of urinary baseline d-mannose/creatinine ratios was significantly different between the responder (mean = 0.337 ± 0.158) and nonresponder (mean = 0.692 ± 0.444; p = 0.016) groups. Urinary post d-mannose/creatinine ratios did not significantly differ between the two groups (p = 0.46). d-mannose-naïve patients had few responders, and age and urinary creatinine did not affect the findings. CONCLUSION: This preliminary study on d-mannose challenge tests indicates a urine response if urinary d-mannose/creatinine ratio is low, which it was in some women with a history of RUTIs.


Asunto(s)
Manosa , Infecciones Urinarias , Humanos , Femenino , Manosa/uso terapéutico , Proyectos Piloto , Creatinina , Infecciones Urinarias/prevención & control , Infecciones Urinarias/tratamiento farmacológico
4.
World J Urol ; 40(7): 1723-1730, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35665841

RESUMEN

PURPOSE: To study human bladder biopsies to investigate urothelial response to UTI, expression of uroplakin, and urothelial response after healing from cystoscopy with electrofulguration (CEF) treatment for antibiotic-recalcitrant RUTI. METHODS: Following IRB approval, cold cup bladder biopsies from "no cystitis" and "cystitis" regions were obtained from women with antibiotic-recalcitrant rUTI undergoing CEF under anesthesia. "No cystitis" and "cystitis" biopsies from 14 patients (5 had prior CEF, 9 naïve) were analyzed by immunofluorescence (IF) confocal microscopy using antibodies against uroplakin-IIIa. For an additional 6 patients (2 prior CEF, 4 naïve), only "cystitis" area biopsies were taken and analyzed. Cytokeratin 5 (marker for squamous metaplasia) staining was performed on 14 patients. RESULTS: In healthy tissue, uroplakin-IIIa staining was observed as a contiguous line on the luminal surface of umbrella cells. In "cystitis" areas for 19/20 patients, there was either no uroplakin-IIIa staining observed or spotty (+) staining. The "cystitis" regions of all patients had less intense uroplakin-IIIa staining compared to the matched "no cystitis" area in the same patient. In patients post-CEF but requiring repeat EF for persistent RUTI lesions, healed areas served as control and in 3 of 7 patients no uroplakin-IIIa staining was observed. Squamous metaplasia was observed in 10 patients. CONCLUSION: In bladders of postmenopausal women with antibiotic-recalcitrant RUTI, areas with visible cystitis expressed less uroplakin-IIIa, supporting the model of urothelial exfoliation in response to UTI.


Asunto(s)
Carcinoma de Células Escamosas , Cistitis , Infecciones Urinarias , Antibacterianos , Carcinoma de Células Escamosas/patología , Cistitis/metabolismo , Femenino , Humanos , Metaplasia/metabolismo , Metaplasia/patología , Proyectos Piloto , Posmenopausia , Vejiga Urinaria/patología , Uroplaquina III/metabolismo
5.
Molecules ; 27(17)2022 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-36080288

RESUMEN

Plants are sources of sunscreen ingredients that prevent cellular mutations involved in skin cancer and aging. This study investigated the sunscreen properties of the extracts from some ornamental plants growing in Colombia. The UV filter capability of the flower extracts obtained from Rosa centifolia L., Posoqueria latifolia (Rudge) Schult, and Ipomoea horsfalliae Hook. was examined. Photoprotection efficacies were evaluated using in vitro indices such as sun protection factor and critical wavelength. UVB antigenotoxicity estimates measured with the SOS Chromotest were also obtained. Extract cytotoxicity and genotoxicity were studied in human fibroblasts using the trypan blue exclusion and Comet assays, respectively. Major compounds of the promising flower extracts were identified by UHPLC-ESI+-Orbitrap-MS. The studied extracts showed high photoprotection efficacy and antigenotoxicity against UVB radiation, but only the P. latifolia extract showed broad-spectrum photoprotection at non-cytotoxic concentrations. The P. latifolia extract appeared to be safer for human fibroblast cells and the R. centifolia extract was shown to be moderately cytotoxic and genotoxic at the highest assayed concentrations. The I. horsfalliae extract was unequivocally cytotoxic and genotoxic. The major constituents of the promising extracts were as follows: chlorogenic acid, ecdysterone 20E, rhamnetin-rutinoside, cis-resveratrol-diglucoside, trans-resveratrol-diglucoside in P. latifolia; quercetin, quercetin-glucoside, quercetin-3-rhamnoside, kaempferol, kaempferol-3-glucoside, and kaempferol-rhamnoside in R. centifolia. The potential of the ornamental plants as sources of sunscreen ingredients was discussed.


Asunto(s)
Quempferoles , Protectores Solares , Flores , Glucósidos , Humanos , Extractos Vegetales/farmacología , Plantas , Quercetina , Protectores Solares/farmacología , Rayos Ultravioleta
6.
Glob Chang Biol ; 27(4): 904-928, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33159712

RESUMEN

Simulation models represent soil organic carbon (SOC) dynamics in global carbon (C) cycle scenarios to support climate-change studies. It is imperative to increase confidence in long-term predictions of SOC dynamics by reducing the uncertainty in model estimates. We evaluated SOC simulated from an ensemble of 26 process-based C models by comparing simulations to experimental data from seven long-term bare-fallow (vegetation-free) plots at six sites: Denmark (two sites), France, Russia, Sweden and the United Kingdom. The decay of SOC in these plots has been monitored for decades since the last inputs of plant material, providing the opportunity to test decomposition without the continuous input of new organic material. The models were run independently over multi-year simulation periods (from 28 to 80 years) in a blind test with no calibration (Bln) and with the following three calibration scenarios, each providing different levels of information and/or allowing different levels of model fitting: (a) calibrating decomposition parameters separately at each experimental site (Spe); (b) using a generic, knowledge-based, parameterization applicable in the Central European region (Gen); and (c) using a combination of both (a) and (b) strategies (Mix). We addressed uncertainties from different modelling approaches with or without spin-up initialization of SOC. Changes in the multi-model median (MMM) of SOC were used as descriptors of the ensemble performance. On average across sites, Gen proved adequate in describing changes in SOC, with MMM equal to average SOC (and standard deviation) of 39.2 (±15.5) Mg C/ha compared to the observed mean of 36.0 (±19.7) Mg C/ha (last observed year), indicating sufficiently reliable SOC estimates. Moving to Mix (37.5 ± 16.7 Mg C/ha) and Spe (36.8 ± 19.8 Mg C/ha) provided only marginal gains in accuracy, but modellers would need to apply more knowledge and a greater calibration effort than in Gen, thereby limiting the wider applicability of models.


Asunto(s)
Carbono , Suelo , Agricultura , Carbono/análisis , Francia , Federación de Rusia , Suecia , Incertidumbre , Reino Unido
7.
Glob Chang Biol ; 26(1): 219-241, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31469216

RESUMEN

There is growing international interest in better managing soils to increase soil organic carbon (SOC) content to contribute to climate change mitigation, to enhance resilience to climate change and to underpin food security, through initiatives such as international '4p1000' initiative and the FAO's Global assessment of SOC sequestration potential (GSOCseq) programme. Since SOC content of soils cannot be easily measured, a key barrier to implementing programmes to increase SOC at large scale, is the need for credible and reliable measurement/monitoring, reporting and verification (MRV) platforms, both for national reporting and for emissions trading. Without such platforms, investments could be considered risky. In this paper, we review methods and challenges of measuring SOC change directly in soils, before examining some recent novel developments that show promise for quantifying SOC. We describe how repeat soil surveys are used to estimate changes in SOC over time, and how long-term experiments and space-for-time substitution sites can serve as sources of knowledge and can be used to test models, and as potential benchmark sites in global frameworks to estimate SOC change. We briefly consider models that can be used to simulate and project change in SOC and examine the MRV platforms for SOC change already in use in various countries/regions. In the final section, we bring together the various components described in this review, to describe a new vision for a global framework for MRV of SOC change, to support national and international initiatives seeking to effect change in the way we manage our soils.


Asunto(s)
Secuestro de Carbono , Gases de Efecto Invernadero , Agricultura , Carbono , Suelo
8.
J Med Syst ; 43(6): 175, 2019 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-31069548

RESUMEN

The Preparadxs app was designed to enhace the prevention of the HIV and other sexually transmitted infections transmission through the empowerment of the user. The purpose of this study is to determine the usability and perception about the app among real users. In this prospective cross-sectional study all app end-users were asked to answer the System Usability Scale and question regarding app capability to reduce sexually transmitted infections in the future. Influence of several variables (gender identity, educational level and digital native condition) was explored. A total of 69 users answered the survey during study period. Most of them were male and had university studies. Final usability score was 80,8 points which means a good, near excellent usability. No differences in usability scores were observed regarding to gender identity, native condition or educational level. Most users were strongly agree (56,5%) or agree (28,9%) with app potential to reduce the incidence of HIV and other STIs in the future.


Asunto(s)
Infecciones por VIH/prevención & control , Enfermedades de Transmisión Sexual/prevención & control , Programas Informáticos , Estudios Transversales , Femenino , Humanos , Masculino , Encuestas y Cuestionarios , Interfaz Usuario-Computador , Tecnología Inalámbrica
9.
J Environ Qual ; 47(4): 644-653, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30025039

RESUMEN

Soil organic C (SOC) stock assessments at the regional scale under climate change scenarios are of paramount importance in implementing soil management practices to mitigate climate change. In this study, we estimated the changes in SOC sequestration under climate change conditions in agricultural land in Spain using the RothC model at the regional level. Four Intergovernmental Panel on Climate Change (IPCC) climate change scenarios (CGCM2-A2, CGCM2-B2, ECHAM4-A2, and ECHAM4-B2) were used to simulate SOC changes during the 2010 to 2100 period across a total surface area of 2.33 × 10 km. Although RothC predicted a general increase in SOC stocks by 2100 under all climate change scenarios, these SOC sequestration rates were smaller than those under baseline conditions. Moreover, this SOC response differed among climate change scenarios, and in some situations, some losses of SOC occurred. The greatest losses of C stocks were found mainly in the ECHAM4 (highest temperature rise and precipitation drop) scenarios and for rainfed and certain woody crops (lower C inputs). Under climate change conditions, management practices including no-tillage for rainfed crops and vegetation cover for woody crops were predicted to double and quadruple C sequestration rates, reaching values of 0.47 and 0.35 Mg C ha yr, respectively.


Asunto(s)
Carbono , Cambio Climático , Suelo/química , Agricultura , Modelos Teóricos , España
10.
Matern Child Health J ; 20(2): 477-83, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26520153

RESUMEN

OBJECTIVES: This study of primarily Latino caregivers and Latino child welfare-involved children had the following aims: (1) explore the return appointment adherence patterns at a pediatric medical clinic; and (2) determine the relationship of adherence to return appointments and caregiver, child, and clinic variables. METHODS: The sample consisted of caregivers of child welfare-involved children who were asked to make a pediatric outpatient clinic return appointment (N = 87). Predictors included caregiver demographics, child medical diagnoses and age, and clinic/convenience factors including distance from the clinic to caregiver's home, days until the return appointment, reminder telephone call, Latino provider, and additional specialty appointment. Predictors were examined using χ(2) and t tests of significance. RESULTS: Thirty-nine percent of all caregivers were nonadherent in returning for pediatric appointments. When return appointments were scheduled longer after the initial appointment, caregivers were less likely to bring children back for medical care. CONCLUSIONS: The 39 % missed return appointment rate in this study is higher than other similar pediatric populations. Better coordination between pediatricians and caregivers in partnership with child welfare case workers is needed to ensure consistent follow-up regarding health problems, especially when appointments are not scheduled soon after the initial appointment.


Asunto(s)
Citas y Horarios , Cuidadores , Protección a la Infancia , Hispánicos o Latinos/psicología , Cooperación del Paciente/etnología , Pediatría , Adulto , Instituciones de Atención Ambulatoria , Niño , Atención a la Salud/organización & administración , Femenino , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Los Angeles , Masculino , Persona de Mediana Edad , Cooperación del Paciente/psicología , Sistemas Recordatorios , Encuestas y Cuestionarios , Teléfono , Estados Unidos
11.
J Strength Cond Res ; 30(7): 2049-56, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27328276

RESUMEN

Gallardo-Fuentes, F, Gallardo-Fuentes, J, Ramírez-Campillo, R, Balsalobre-Fernández, C, Martínez, C, Caniuqueo, A, Cañas, R, Banzer, W, Loturco, I, Nakamura, FY, and Izquierdo, M. Intersession and intrasession reliability and validity of the My Jump app for measuring different jump actions in trained male and female athletes. J Strength Cond Res 30(7): 2049-2056, 2016-The purpose of this study was to analyze the concurrent validity and reliability of the iPhone app named My Jump for measuring jump height in 40-cm drop jumps (DJs), countermovement jumps (CMJs), and squat jumps (SJs). To do this, 21 male and female athletes (age, 22.1 ± 3.6 years) completed 5 maximal DJs, CMJs, and SJs on 2 separate days, which were evaluated using a contact platform and the app My Jump, developed to calculate jump height from flight time using the high-speed video recording facility on the iPhone. A total of 630 jumps were compared using the intraclass correlation coefficient (ICC), Bland-Altman plots, Pearson's product moment correlation coefficient (r), Cronbach's alpha (α), and coefficient of variation (CV). There was almost perfect agreement between the measurement instruments for all jump height values (ICC = 0.97-0.99), with no differences between the instruments (p > 0.05; mean difference of 0.2 cm). Almost perfect correlation was observed between the measurement instruments for SJs, CMJs, and DJs (r = 0.96-0.99). My Jump showed very good within-subject reliability (α = 0.94-0.99; CV = 3.8-7.6) and interday reliability (r = 0.86-0.95) for SJs, CMJs, and DJs in all subjects. Therefore, the iPhone app named My Jump provides reliable intersession and intrasession data, as well as valid measurements for maximal jump height during fast (i.e., DJs) and slow (i.e., CMJs) stretch-shortening cycle muscle actions, and during concentric-only explosive muscle actions (i.e., SJs), in both male and female athletes in comparison with a professional contact platform.


Asunto(s)
Rendimiento Atlético/fisiología , Prueba de Esfuerzo/métodos , Aplicaciones Móviles , Adulto , Prueba de Esfuerzo/instrumentación , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Teléfono Inteligente , Grabación en Video , Adulto Joven
12.
J Cell Physiol ; 230(12): 3068-75, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25989529

RESUMEN

The acrosome reaction (AR) is the exocytosis of the acrosomal vesicle in response to different physiological and non-physiological stimuli. Particularly in mammals, the AR is needed for sperm to fuse with the oocyte plasma membrane, and it occurs only in capacitated sperm. Previous evidence in the literature indicates that extracellular ATP induces the AR in capacitated human and bovine spermatozoa, but its receptor has not yet been identified. The aim of this work was to define a putative ATP receptor in rat spermatozoa using pharmacological and biochemical approaches. We found that ATP induced the AR only in capacitated rat spermatozoa, which was inhibited in the presence of two general inhibitors of ATP receptors (P2 receptors), Suramin, and oxidized ATP (oATP), and one inhibitor of P2X receptor (pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid [PPADS]). In addition, the AR induced by ATP in capacitated rat spermatozoa was inhibited by brilliant blue-G (BB-G) and 17-ß-oestradiol, two blockers of P2X7 receptors. Moreover, the ATP analog 2'(3')-O-(4-benzoylbenzoyl) ATP (BzATP) was almost 500 times more potent than ATP to induce the AR, which agrees with the pharmacology of a P2X7 receptor. Here, we show the presence of P2X7 receptor by Western blot and its localization in the tail and acrosome by indirect immunofluorescence. Finally, we quantify the presence of ATP in the rat oviduct during the estrous cycle. We found that the ATP concentration within the lumen of the oviduct is similar to those required to induce acrosome reaction, which agree with its role during in vivo fertilization. Therefore, our results strongly suggest that ATP induces the AR in capacitated rat spermatozoa through a P2X7 receptor, which may be functional during in vivo fertilization.


Asunto(s)
Reacción Acrosómica/efectos de los fármacos , Acrosoma/efectos de los fármacos , Adenosina Trifosfato/farmacología , Agonistas del Receptor Purinérgico P2X/farmacología , Receptores Purinérgicos P2X7/efectos de los fármacos , Acrosoma/metabolismo , Animales , Relación Dosis-Respuesta a Droga , Ciclo Estral/metabolismo , Femenino , Masculino , Oviductos/metabolismo , Antagonistas del Receptor Purinérgico P2X/farmacología , Ratas Sprague-Dawley , Receptores Purinérgicos P2X7/metabolismo , Transducción de Señal/efectos de los fármacos , Factores de Tiempo
13.
Cancer Cell Int ; 15: 47, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26221079

RESUMEN

BACKGROUND: Most of the knowledge about the mechanisms of multidrug resistance in lung cancer has been achieved through the use of cell lines isolated from tumours cultivated either in suspensions of isolated cells or in monolayers and following exposition to different cytostatic agents. However, tumour cell lines growing as multicellular tumour spheroids (MTS) frequently develop multicellular resistance in a drug-independent form. The aim of this study was to characterize the phenotypic and functional differences between two human NSCLC cell lines (INER-37 and INER-51) grown as traditional monolayer cultures versus as MTS. METHODS: After 72 hours treatment with anticancer drugs, chemosensitivity in monolayers and tumour spheroids cultures was assessed using MTT assay. Reverse transcription-polymerase chain reaction was employed to detect the mRNAs of multidrug resistance-related genes. The expression of P-gp was analyzed by immunohistochemical staining and cell cycle profiles were analyzed using FACS. RESULTS: The results indicate that when grown as MTS each lung cancer cell line had different morphologies as well as and abrogation of cell proliferation with decrease of the G2/M phase. Also, MTS acquired multicellular resistance to several chemotherapeutic agents in only a few days of culture which were accomplished by significant changes in the expression of MDR-related genes. CONCLUSION: Overall, the MTS culture changed the cellular response to drugs nevertheless each of the cell lines studied seems to implement different mechanisms to acquire multicellular resistance.

14.
AJR Am J Roentgenol ; 205(1): W19-31, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26102414

RESUMEN

OBJECTIVE: This article discusses the clinical challenge of low-radiation-dose examinations, the commonly used approaches for dose optimization, and their effect on image quality. We emphasize practical aspects of the different iterative reconstruction techniques, along with their benefits, pitfalls, and clinical implementation. CONCLUSION: The widespread use of CT has raised concerns about potential radiation risks, motivating diverse strategies to reduce the radiation dose associated with CT. CT manufacturers have developed alternative reconstruction algorithms intended to improve image quality on dose-optimized CT studies, mainly through noise and artifact reduction. Iterative reconstruction techniques take unique approaches to noise reduction and provide distinct strength levels or settings.


Asunto(s)
Dosis de Radiación , Protección Radiológica/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Radiografía Abdominal/métodos , Tomografía Computarizada por Rayos X/métodos , Algoritmos , Humanos
15.
AJR Am J Roentgenol ; 204(2): W176-83, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25615778

RESUMEN

OBJECTIVE. The objective of our study was to compare the performance of three hybrid iterative reconstruction techniques (IRTs) (ASiR, iDose4, SAFIRE) and their respective strengths for image noise reduction on low-dose CT examinations using filtered back projection (FBP) as the standard reference. Also, we compared the performance of these three hybrid IRTs with two model-based IRTs (Veo and IMR) for image noise reduction on low-dose examinations. MATERIALS AND METHODS. An anthropomorphic abdomen phantom was scanned at 100 and 120 kVp and different tube current-exposure time products (25-100 mAs) on three CT systems (for ASiR and Veo, Discovery CT750 HD; for iDose4 and IMR, Brilliance iCT; and for SAFIRE, Somatom Definition Flash). Images were reconstructed using FBP and using IRTs at various strengths. Nine noise measurements (mean ROI size, 423 mm(2)) on extracolonic fat for the different strengths of IRTs were recorded and compared with FBP using ANOVA. Radiation dose, which was measured as the volume CT dose index and dose-length product, was also compared. RESULTS. There were no significant differences in radiation dose and image noise among the scanners when FBP was used (p > 0.05). Gradual image noise reduction was observed with each increasing increment of hybrid IRT strength, with a maximum noise suppression of approximately 50% (48.2-53.9%). Similar noise reduction was achieved on the scanners by applying specific hybrid IRT strengths. Maximum noise reduction was higher on model-based IRTs (68.3-81.1%) than hybrid IRTs (48.2-53.9%) (p < 0.05). CONCLUSION. When constant scanning parameters are used, radiation dose and image noise on FBP are similar for CT scanners made by different manufacturers. Significant image noise reduction is achieved on low-dose CT examinations rendered with IRTs. The image noise on various scanners can be matched by applying specific hybrid IRT strengths. Model-based IRTs attain substantially higher noise reduction than hybrid IRTs irrespective of the radiation dose.


Asunto(s)
Artefactos , Procesamiento de Imagen Asistido por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Humanos , Fantasmas de Imagen
16.
Acta Gastroenterol Latinoam ; 44(3): 233-8, 2014.
Artículo en Español | MEDLINE | ID: mdl-26742295

RESUMEN

INTRODUCTION: There is considerable evidence on the direct relationship between higher volume and lower mortality in the pancreatoduodenectomy (DPC). However, there is little evidence of morbidity and mortality in the process of building a high-volume pancreatic surgery center. Objective. To evaluate the morbidity and mortality of the DPC in the process of building a high-volume center for pancreatic resection. METHODS: All consecutive patients undergoing DPC from July 2007 through July 2009 at a single center were included. High volume center was defined as that doing more than 19 DPC per year and high volume surgeon as that doing 16 or more DPC per year. The analysis of data was carried out in two periods according to the number of DPC per year: the first (1998 to 2005) as low volume center and the second (2006 to 2012) as high volume center. RESULTS: Three hundred and thirty five DPC were conducted consecutively. All surgeries were performed by a high volume surgeon. One hundred and seven patients were operated in the first period and 228 in the second period. There were no significant differences in morbidity and mortality between the both periods. In the second period there were significantly less operative time and minor length ofstay. CONCLUSIONS: High volume surgeons in pancreatic surgery can transfer their experience to the creation of a high volume pancreatic surgery center without sacrificing the morbidity and mortality.


Asunto(s)
Competencia Clínica/estadística & datos numéricos , Hospitales de Alto Volumen/estadística & datos numéricos , Pancreaticoduodenectomía/efectos adversos , Adulto , Anciano , Femenino , Humanos , Unidades de Cuidados Intensivos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Morbilidad , Tempo Operativo , Pancreatectomía/efectos adversos , Pancreatectomía/estadística & datos numéricos , Fístula Pancreática/mortalidad , Pancreaticoduodenectomía/mortalidad , Pancreaticoduodenectomía/estadística & datos numéricos , Hemorragia Posoperatoria/mortalidad , Periodo Posoperatorio , Cirujanos/estadística & datos numéricos , Resultado del Tratamiento , Adulto Joven
17.
Life Sci ; 337: 122341, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38101613

RESUMEN

Since DNA damage can occur spontaneously or be produced by the environmental genotoxins in living cells, it is important to investigate compounds that can reverse or protect DNA damage. An appropriate methodology is essential for the responsive identification of protection offered against DNA damage. This review includes information on the current state of knowledge on prokaryotic cell-based assays (SOS chromotest, umu test, vitotox assay) and cytogenetic techniques (micronucleus assay, chromosome aberration test and sister chromatid exchange assay) with an emphasis on the possibility to explore genoprotective compounds. Throughout the last decade, studies have extrapolated the scientific methodologies utilized for genotoxicity to assess genoprotective compounds. Therefore, shortcomings of genotoxicity studies are also mirrored in antigenotoxicity studies. While regulatory authorities around the world (OECD, US-EPA and ICH) continue to update diverse genotoxic assay strategies, there are still no clear guidelines/approaches for efficient experimental design to screen genoprotective compounds. As a consequence, non-synergetic and inconsistent implementation of the test method by the researchers to execute such simulations has been adopted, which inevitably results in unreliable findings. The review has made the first attempt to collect various facets of experimentally verified approaches for evaluating genoprotective compounds, as well as to acknowledge potential significance and constraints, and further focus on the assessment of end points which are required to validate such action. Henceforth, the review makes an incredible commitment by permitting readers to equate several components of their test arrangement with the provided simplified information, allowing the selection of convenient technique for the predefined compound from a central repository.


Asunto(s)
Daño del ADN , Mutágenos , Humanos , Pruebas de Mutagenicidad/métodos , Mutágenos/toxicidad , Pruebas de Micronúcleos , Aberraciones Cromosómicas
18.
PeerJ ; 12: e17507, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38832030

RESUMEN

Objective: (1) This trial will compare the clinical and psychosocial effectiveness of in-group and individually pain neuroscience education (PNE) in patients with chronic low back pain (CLBP). In addition, (2) the influence of social determinants of health on post-treatment results will be analyzed. Methods: A three-arm randomized controlled trial will be conducted. Sixty-nine participants with CLBP will be recruited in a 1:1:1 ratio. Participants, assessor, and statistician will be blinded to group assignment. The PNE intervention will be adapted to the context of the participants. An experimental group (n = 33) will receive PNE in an in-group modality, the other experimental group (n = 33) will receive PNE in an individually modality and the control group (n = 33) will continue with usual care. Additionally, participants will be encouraged to stay active by walking for 20-30 min 3-5 times per week and will be taught an exercise to improve transversus abdominis activation (bracing or abdominal following). The outcome measures will be fear avoidance and beliefs, pressure pain threshold, pain self-efficacy, catastrophizing, pain intensity, and treatment expectation. Outcome measures will be collected at one-week before intervention, immediately post-intervention, and four-weeks post-intervention. Conclusion: The innovative approach of PNE oriented to fear beliefs proposed in this study could broaden the application strategies of this educational therapeutic modality. Impact. Contextualized PNE delivered by physical therapist could be essential to achieve a good cost-effectiveness ratio of this intervention to improve the clinical condition of people with CLBP.


Asunto(s)
Dolor Crónico , Dolor de la Región Lumbar , Neurociencias , Educación del Paciente como Asunto , Humanos , Dolor de la Región Lumbar/psicología , Dolor de la Región Lumbar/terapia , Neurociencias/educación , Educación del Paciente como Asunto/métodos , Dolor Crónico/terapia , Dolor Crónico/psicología , Masculino , Femenino , Adulto , Catastrofización/psicología , Dimensión del Dolor , Persona de Mediana Edad , Resultado del Tratamiento , Autoeficacia , Terapia por Ejercicio/métodos
19.
Patient Educ Couns ; 123: 108201, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38387389

RESUMEN

OBJECTIVE: (1) To identify the characteristics of PNE programs in terms of teaching-learning strategies, session modality, content delivery format, number of sessions, total minutes and instructional support material used in patients with chronic musculoskeletal pain, (2) to describe PNE adaptations for patients with different educational levels or cultural backgrounds, and (3) to describe the influence of the patient's educational level or cultural background on the effects of PNE. METHODS: The PRISMA guideline for scoping reviews was followed. Nine databases were systematically searched up to July 8, 2023. Articles that examined clinical or psychosocial variables in adults with chronic musculoskeletal pain who received PNE were included. RESULTS: Seventy-one articles were included. Studies found benefits of PNE through passive/active teaching-learning strategies with group/individual sessions. However, PNE programs presented great heterogeneity and adaptations to PNE were poorly reported. Most studies did not consider educational level and culture in the effects of PNE. CONCLUSIONS: Despite the large number of studies on PNE and increased interest in this intervention, the educational level and culture are poorly reported in the studies. PRACTICAL IMPLICATIONS: It is recommended to use passive and/or active teaching-learning strategies provided in individual and/or group formats considering the patient's educational level and culture.


Asunto(s)
Dolor Crónico , Neurociencias , Educación del Paciente como Asunto , Humanos , Dolor Crónico/terapia , Educación del Paciente como Asunto/métodos , Neurociencias/educación , Manejo del Dolor/métodos , Aprendizaje , Escolaridad , Enseñanza , Dolor Musculoesquelético/terapia
20.
Acta Trop ; 254: 107195, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38548212

RESUMEN

A clinical case of an adult horse with invasive, ulcerative, proliferative, pyogranulomatous disease of the skin (tumor) in the shoulder region is presented. The mass had a granulomatous and crater-shaped appearance, with serosanguinous discharge and the presence of fistulas with caseous material. The tumor was removed by surgery and sent to the laboratory for diagnosis. Histopathology was performed using Grocott-Gomori methenamine silver stain. The presence of necrotic material, fibrosis, infiltrated cells, and brown-colored hyphae, characteristic of members of the genus Pythium, were observed. To identify the infecting species, conventional PCRs for the amplification of the ITS-1 was carried out. Histopathological and PCR tests confirmed infection by a Pythium insidiosum strain closely associated with previous records from the US and Central America. Our report represents the first molecularly confirmed case of equine pythiosis in Mexico.


Asunto(s)
Enfermedades de los Caballos , Pitiosis , Pythium , Animales , Pitiosis/diagnóstico , Pitiosis/microbiología , Pitiosis/patología , Caballos , Pythium/aislamiento & purificación , Pythium/genética , Pythium/clasificación , Enfermedades de los Caballos/parasitología , Enfermedades de los Caballos/microbiología , Enfermedades de los Caballos/diagnóstico , México , Reacción en Cadena de la Polimerasa , ADN Espaciador Ribosómico/genética , Masculino , Histocitoquímica , Piel/patología , Piel/microbiología , Piel/parasitología
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