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1.
Parkinsons Dis ; 2021: 8871549, 2021.
Article in English | MEDLINE | ID: mdl-34094501

ABSTRACT

INTRODUCTION: In a degenerative disorder such as Parkinson's disease (PD), it is important to establish clinical stages that allow to know the course of the disease. Our aim was to analyze whether a scale combining Hoehn and Yahr's motor stage (H&Y) and the nonmotor symptoms burden (NMSB) (assessed by the nonmotor symptoms scale (NMSS)) provides information about the disability and the patient's quality of life (QoL) with regard to a defined clinical stage. MATERIALS AND METHODS: Cross-sectional study in which 603 PD patients from the COPPADIS cohort were classified according to H&Y (1, stage I; 2, stage II; 3, stage III; 4, stage IV/V) and NMSB (A: NMSS = 0-20; B: NMSS = 21-40; C: NMSS = 41-70; D: NMSS ≥ 71) in 16 stages (HY.NMSB, from 1A to 4D). QoL was assessed with the PDQ-39SI, PQ-10, and EUROHIS-QOL8 and disability with the Schwab&England ADL (Activities of Daily Living) scale. RESULTS: A worse QoL and greater disability were observed at a higher stage of H&Y and NMSB (p < 0.0001). Combining both (HY.NMSB), patients in stages 1C and 1D and 2C and 2D had significantly worse QoL and/or less autonomy for ADL than those in stages 2A and 2B and 3A and 3B, respectively (p < 0.005; e.g., PDQ-39SI in 1D [n = 15] vs 2A [n = 101]: 28.6 ± 17.1 vs 7.9 ± 5.8; p < 0.0001). CONCLUSION: The HY.NMSB scale is simple and reflects the degree of patient involvement more accurately than the H&Y. Patients with a lower H&Y stage may be more affected if they have a greater NMS burden.

2.
J Vet Cardiol ; 35: 25-41, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33812131

ABSTRACT

INTRODUCTION/OBJECTIVES: In the past few years, novel markers such as the interval between the peak and the end of T-wave (Tpte) and Tpte/QT ratio have been shown to have high sensitivity for ventricular arrhythmias and mortality. We analyzed these and other parameters of ventricular repolarization, such as QT interval, QT interval corrected for heart rate (QTc), and QT dispersion (QTd) in dogs with myxomatous mitral valve disease (MMVD). Additionally, we investigated their relationship with the progression of the disease, echocardiographic parameters, and ventricular arrhythmias and assessed their prognostic value with development of clinical signs or mortality as the final outcome. ANIMALS, MATERIALS AND METHODS: Epidemiological, clinical, echocardiographic, and electrocardiographic data were obtained from 236 dogs with MMVD and 15 healthy dogs. Prognostic and survival information was also recorded for the MMVD group. All ventricular repolarization indices were measured in 10 lead electrocardiographic recordings. RESULTS: With the exception of the QT interval, most repolarization markers increased along with the frequency of arrhythmias and with the progression of MMVD. The parameters that best identified ventricular arrhythmias (AUC > 0.7) were Tpte (aVR, rV2, average rV2-V10, average rV2-V4) and Tpte/QT (II, aVR, rV2). In survival analysis, statistically significant markers with the highest differences in median survival were Tpte (maximum of any lead, maximum rV2-V10), QTc aVR, and Tpte rV2. CONCLUSION: Tpte and Tpte/QT are good non-invasive markers for clinical risk stratification in dogs with MMVD.


Subject(s)
Dog Diseases , Heart Valve Diseases , Animals , Arrhythmias, Cardiac/veterinary , Dogs , Electrocardiography/veterinary , Heart Rate , Heart Valve Diseases/veterinary , Mitral Valve
4.
Int J Geriatr Psychiatry ; 36(5): 627-646, 2021 05.
Article in English | MEDLINE | ID: mdl-33169885

ABSTRACT

BACKGROUND: Although depression is known to be frequent in Parkinson's disease (PD), it is unclear how mood can change and/or impact on patient's quality of life (QoL) over time. Our aim was to analyze the frequency of depression, mood related factors and the contribution of mood to a patient's QoL perception in regard to disease duration. METHODS: PD patients recruited from the COPPADIS cohort from January 2016 to November 2017 were included in this cross-sectional study. Three groups were defined: <5 years (Group A); from 5 to <10 years (Group B); ≥10 years (Group C). Analysis with well-planned linear regression models was conducted to determine how different factors contribute to mood (Beck Depression Inventory-II [BDI-II] as dependent variable), to health-related QoL (39-item Parkinson's Disease Questionnaire [PDQ-39SI] as dependent variable) and to global QoL (European Health Interview Survey - Quality of Life Eight-Item Index [EUROHIS-QOL8] as dependent variable). RESULTS: Six hundred and sixty-three PD patients (62.6 ± 8.9 years old, 59.6% males) were included: Group A, 50.1% (n = 332); Group B, 33.3% (n = 221) and Group C, 16.6% (n = 110). There were no differences between the three groups in terms of the frequency of depressive symptoms nor the frequency of depression type (major vs. minor vs. subthreshold) (p = 0.729). However, the unique percent variance of PDQ-39SI and EUROHIS-QOL8 explained by BDI-II total score was 2 (23.7%) and threefold (26.9%), respectively, in Group C compared to the other two groups. EUROHIS-QOL8 total score provided the highest unique contribution to mood (16.8%). CONCLUSIONS: Although depression-type frequency does not appear to change over time in PD; the contribution of mood on QoL perception is greater in patients with longer disease duration.


Subject(s)
Parkinson Disease , Aged , Cross-Sectional Studies , Female , Health Surveys , Humans , Male , Parkinson Disease/epidemiology , Quality of Life , Surveys and Questionnaires
5.
Environ Monit Assess ; 191(10): 635, 2019 Sep 15.
Article in English | MEDLINE | ID: mdl-31522254

ABSTRACT

This study aimed to analyze the spatial and temporal variation of the vegetation in the northern Argentine Puna, utilizing both field sampling and remote-sensing tools. The study was performed within the Pozuelos Biosphere Reserve (Jujuy province, Argentina), which aims to generate socio-economic development compatible with biodiversity conservation. Our study was designed to analyze the dynamics of the Puna vegetation at local scale and assess and monitor the seasonal (dry and wet seasons), interannual, and spatial variation of the vegetation cover, biomass, dominant species, and vegetation indices. Ten vegetation units (with differences in composition, cover, and high and low stratum biomass) were identified at our study site. The diversity of these vegetation units correlated with geomorphology and soil type. In the dry season, the vegetation unit with greatest vegetation cover and biomass was the Festuca chrysophylla grassland, whereas in the wet season, the units with greatest cover and biomass were vegas (peatlands) and short grasslands. The Festuca chrysophylla grasslands and short grasslands were located in areas with clay soils, except peatlands, associated with valleys and coarse-texture soils. The vegetation indices used (NDVI, SAVI, and MSAVI2) were able to differentiate functional types of vegetation and showed a good statistical fit with cover values. Our results suggest that the integrated utilization of remote-sensing tools and field surveys improves the assessment of the Puna vegetation and would allow a periodic monitoring at production unit scale taking into account its spatial and temporal variation.


Subject(s)
Environmental Monitoring/methods , Grassland , Plants/classification , Argentina , Biodiversity , Biomass , Parks, Recreational , Remote Sensing Technology , Seasons , Soil/chemistry
6.
Parkinsonism Relat Disord ; 66: 151-157, 2019 09.
Article in English | MEDLINE | ID: mdl-31409572

ABSTRACT

OBJECTIVE: To identify factors related to a poor health-related and global quality of life (QoL) in a cohort of non-demented Parkinson's disease (PD) patients and compare to a control group. METHODS: The data correspond to the baseline evaluation of the COPPADIS-2015 Study, an observational, 5-year follow-up, multicenter, evaluation study. Three instruments were used to assess QoL: (1) the 39-item Parkinson's disease Questionnaire (PDQ-39), (2) a subjective rating of global QoL (PQ-10), and (3) the EUROHIS-QOL 8-item index (EUROHIS-QOL8). Multiple linear regression methods were used to evaluate the direct impact of different variables on these QoL measures. RESULTS: QoL was worse in PD patients (n = 692; 62.6 ±â€¯8.9 years old, 60.3% males) than controls (n = 206; 61 ±â€¯8.3 years old, 49.5% males): PDQ-39, 17.1 ±â€¯13.5 vs 4.4 ±â€¯6.3 (p < 0.0001); PQ-10, 7.3 ±â€¯1.6 vs 8.1 ±â€¯1.2 (p < 0.0001); EUROHIS-QOL8, 3.8 ±â€¯0.6 vs 4.2 ±â€¯0.5 (p < 0.0001). A high correlation was observed between PDQ-39 and Non-Motor Symptoms Scale (NMSS) (r = 0.72; p < 0.0001), and PDQ-39 and Beck Depression Inventory-II (BDI-II) (r = 0.65; p < 0.0001). For health-related QoL (PDQ-39), non-motor symptoms burden (NMSS), mood (BDI-II), and gait problems (Freezing Of Gait Questionnaire [FOGQ]) provided the highest contribution to the model (ß = 0.32, 0.28, and 0.27, respectively; p < 0.0001); whereas mood and gait problems contributed the most to global QoL (PQ-10, ß = -0.46 and -0.21, respectively; EUROHIS-QOL8, ß = -0.44 and -0.23, respectively). CONCLUSIONS: QoL is worse in PD patients than in controls. Mood, non-motor symptoms burden, and gait problems seem to be the most relevant factors affecting health-related and global perceived QoL in non-demented PD patients.


Subject(s)
Affective Symptoms/physiopathology , Gait Disorders, Neurologic/physiopathology , Parkinson Disease/physiopathology , Quality of Life , Affective Symptoms/etiology , Aged , Female , Follow-Up Studies , Gait Disorders, Neurologic/etiology , Humans , Male , Middle Aged , Parkinson Disease/complications , Severity of Illness Index
7.
Eur J Neurol ; 26(11): 1399-1407, 2019 11.
Article in English | MEDLINE | ID: mdl-31179586

ABSTRACT

BACKGROUND AND PURPOSE: In Parkinson's disease (PD), the course of the disorder is highly variable between patients. Well-designed, prospective studies for identifying PD progression biomarkers are necessary. Our aim was to show the results of baseline evaluations of an ongoing global PD project, COPPADIS-2015 (Cohort of Patients with PArkinson's DIsease in Spain, 2015). METHODS: This was an observational, descriptive, nationwide study (Spain). The recruitment period ended in October 2017. Baseline evaluation included more than 15 validated scales and complementary studies in a subgroup of participants. RESULTS: In total, 1174 subjects from 35 centres were considered valid for baseline analysis: 694 patients (62.6 ± 8.9 years old, 60.3% males), 273 caregivers (58.5 ± 11.9 years old, 31.8% males) and 207 controls (61 ± 8.3 years old, 49.5% males). The mean disease duration was 5.5 ± 4.4 years. Hoehn and Yahr stage was 1 or 2 in 90.7% of the patients whilst 33.9% and 18.1% of them presented motor fluctuations and dyskinesias, respectively. The mean Non-Motor Symptoms Scale total score was 45.4 ± 38.1, and 30.4% of the patients presented cognitive impairment, 16.1% major depression, 12.7% impulse control disorder, 7.2% compulsive behaviour, 57.2% pain and 13.2% falls. Compared to the control group, PD patients presented a significantly higher burden of non-motor symptoms and a worse quality of life. More than 300 subjects conducted complementary studies (serum biomarkers, genetic and neuroimaging). CONCLUSIONS: Parkinson's disease is a complex disorder and different non-motor symptoms are frequently present and are more prevalent than in controls. In real clinical practice it is important to ask for them.


Subject(s)
Parkinson Disease/pathology , Aged , Aged, 80 and over , Caregivers/statistics & numerical data , Cognition Disorders/epidemiology , Cognition Disorders/etiology , Cohort Studies , Comorbidity , Disease Progression , Disruptive, Impulse Control, and Conduct Disorders , Female , Humans , Longitudinal Studies , Male , Mental Disorders/epidemiology , Mental Disorders/etiology , Middle Aged , Movement Disorders/epidemiology , Movement Disorders/etiology , Parkinson Disease/epidemiology , Parkinson Disease/psychology , Prospective Studies , Quality of Life , Socioeconomic Factors , Spain/epidemiology
8.
Comput Methods Biomech Biomed Engin ; 20(14): 1543-1553, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29017357

ABSTRACT

We propose a fully automated methodology for hexahedral meshing of patient-specific structures of the human knee obtained from magnetic resonance images, i.e. femoral/tibial cartilages and menisci. We select eight patients from the Osteoarthritis Initiative and validate our methodology using MATLAB on a laptop computer. We obtain the patient-specific meshes in an average of three minutes, while faithfully representing the geometries with well-shaped elements. We hope to provide a fundamentally different means to test hypotheses on the mechanisms of disease progression by integrating our patient-specific FE meshes with data from individual patients. Download both our meshes and software at http://im.engr.uconn.edu/downloads.php .


Subject(s)
Cartilage/pathology , Knee Joint/pathology , Osteoarthritis/pathology , Automation , Femur/pathology , Humans , Imaging, Three-Dimensional , Magnetic Resonance Imaging , Menisci, Tibial/pathology
9.
J Biomech ; 56: 1-9, 2017 05 03.
Article in English | MEDLINE | ID: mdl-28318603

ABSTRACT

Accurate estimation of peak wall stress (PWS) is the crux of biomechanically motivated rupture risk assessment for abdominal aortic aneurysms aimed to improve clinical outcomes. Such assessments often use the finite element (FE) method to obtain PWS, albeit at a high computational cost, motivating simplifications in material or element formulations. These simplifications, while useful, come at a cost of reliability and accuracy. We achieve research-standard accuracy and maintain clinically applicable speeds by using novel computational technologies. We present a solution using our custom finite element code based on graphics processing unit (GPU) technology that is able to account for added complexities involved with more physiologically relevant solutions, e.g. strong anisotropy and heterogeneity. We present solutions up to 17× faster relative to an established finite element code using state-of-the-art nonlinear, anisotropic and nearly-incompressible material descriptions. We show a realistic assessment of the explicit GPU FE approach by using complex problem geometry, biofidelic material law, double-precision floating point computation and full element integration. Due to the increased solution speed without loss of accuracy, shown on five clinical cases of abdominal aortic aneurysms, the method shows promise for clinical use in determining rupture risk of abdominal aortic aneurysms.


Subject(s)
Aortic Aneurysm, Abdominal , Aortic Rupture , Finite Element Analysis , Humans , Models, Cardiovascular , Reproducibility of Results , Risk , Stress, Mechanical
12.
Comput Math Methods Med ; 2015: 202539, 2015.
Article in English | MEDLINE | ID: mdl-26236390

ABSTRACT

A correct patient-specific identification of the abdominal aortic aneurysm is useful for both diagnosis and treatment stages, as it locates the disease and represents its geometry. The actual thickness and shape of the arterial wall and the intraluminal thrombus are of great importance when predicting the rupture of the abdominal aortic aneurysms. The authors describe a novel method for delineating both the internal and external contours of the aortic wall, which allows distinguishing between vessel wall and intraluminal thrombus. The method is based on active shape model and texture statistical information. The method was validated with eight MR patient studies. There was high correspondence between automatic and manual measurements for the vessel wall area. Resulting segmented images presented a mean Dice coefficient with respect to manual segmentations of 0.88 and a mean modified Hausdorff distance of 1.14 mm for the internal face and 0.86 and 1.33 mm for the external face of the arterial wall. Preliminary results of the segmentation show high correspondence between automatic and manual measurements for the vessel wall and thrombus areas. However, since the dataset is small the conclusions cannot be generalized.


Subject(s)
Aortic Aneurysm, Abdominal/diagnosis , Aortic Aneurysm, Abdominal/pathology , Blood Vessels/pathology , Endothelium, Vascular/pathology , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging , Thrombosis/pathology , Algorithms , Angiography , Biomechanical Phenomena , Humans , Imaging, Three-Dimensional , Models, Statistical , Reproducibility of Results , Software , Thrombosis/diagnosis , Tomography, X-Ray Computed
13.
J Anim Sci ; 93(1): 238-46, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25568372

ABSTRACT

Salmonella enterica serovar Enteritidis is one of the leading causes of food-borne salmonellosis in humans. Poultry is the single largest reservoir, and the consumption of incorrectly processed chicken meat and egg products is the major source of infection. Since 2006, the use of antibiotics as growth promoters has been banned in the European Union, and the dietary inclusion of ß-galactomannans (ßGM) has become a promising strategy to control and prevent intestinal infections. The aim of this study was to investigate the effect of various ßGM-rich products on intestinal morphology in chickens challenged with Salmonella Enteritidis. To assess this effect, a total of 280 male Ross 308 chickens were studied (40 animals per treatment housed in 5 cages). There were 7 treatments, including controls: uninoculated birds fed the basal diet (negative control) and inoculated birds fed the basal diet (positive control) or the basal diet supplemented with Salmosan (1 g/kg), Duraió gum (1 g/kg), Cassia gum (1 g/kg), the cell walls of Saccharomyces cerevisiae (0.5 g/kg), or the antibiotic colistine (0.8 g/kg). The birds were fed these diets from the d 1 to 23, except the animals in the colistine group, which were fed the diet containing the antibiotic only from d 5 to 11. The inoculated animals were orally infected on d 7 with 10(8) cfu of Salmonella Enteritidis. Bird performance per replicate was determined for the whole study period (23 d), and the distal ileum and cecal tonsil of 5 animals per treatment (1 animal per replicate) were observed at different magnification levels (scanning electron, light, and laser confocal microscopy). In the images corresponding to the treatments containing ßGM we observed more mucus, an effect that can be associated with the observation of more goblet cells. Moreover, the images also show fewer M cells, which are characteristic of infected animals. Regarding the morphometric parameters, the animals that received Duraió and Cassia gums show greater (P = 0.001 and P = 0.016, respectively) villus length compared with the animals in the positive control, thus indicating the capacity of these products to increase epithelial surface area. However, no effect (P > 0.05) on microvillus dimensions was detected. In conclusion, the results obtained indicating the beneficial effects of these ßGM on intestinal morphology give more evidence of the positive effects of these supplements in poultry nutrition.


Subject(s)
Chickens/microbiology , Diet/veterinary , Enteritis/veterinary , Intestines/drug effects , Mannans/pharmacology , Poultry Diseases/pathology , Salmonella Infections, Animal/pathology , Salmonella enteritidis , Animal Feed , Animals , Anti-Bacterial Agents/pharmacology , Cecum/drug effects , Cecum/microbiology , Cecum/pathology , Colistin/pharmacology , Dietary Supplements , Enteritis/microbiology , Enteritis/pathology , Galactose/analogs & derivatives , Humans , Ileum/drug effects , Ileum/microbiology , Ileum/pathology , Intestinal Mucosa/drug effects , Intestinal Mucosa/microbiology , Intestinal Mucosa/pathology , Intestines/microbiology , Intestines/pathology , Male , Mannans/administration & dosage , Microvilli/drug effects , Microvilli/microbiology , Microvilli/ultrastructure , Poultry Diseases/microbiology , Salmonella Infections, Animal/microbiology , Salmonella enteritidis/isolation & purification
14.
Mar Pollut Bull ; 85(1): 67-77, 2014 Aug 15.
Article in English | MEDLINE | ID: mdl-25015016

ABSTRACT

This study analyzes the coastal exposure to potential oil spills coming from the various corridors that constitute the Finisterre Traffic Separation Scheme (NW Iberia). A Lagrangian model was executed with results from a realistic configuration of an ocean model during 2012, validated here against High-Frequency (HF) radar-derived surface currents. Virtual particles were released each hour and followed during the next 4 days. A series of maps summarize which regions would be impacted and when. We have learnt, for example, that Cape Finisterre is the most affected area under a wide range of scenarios and that a sensitive area such as the National Park of the Atlantic Islands would require protective actions in less than 24 h if oil spills from the south eventually occurred. A complete analysis by corridor and during specific wind events is available through a web tool, which could be useful for decision makers in case of contingency.


Subject(s)
Environmental Monitoring/methods , Petroleum Pollution/analysis , Geography , Hydrocarbons/analysis , Models, Theoretical , Oceans and Seas , Probability , Radar , Time Factors , Water Pollutants/analysis , Wind
15.
Med Biol Eng Comput ; 52(2): 159-68, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24306943

ABSTRACT

In order to perform finite element (FE) analyses of patient-specific abdominal aortic aneurysms, geometries derived from medical images must be meshed with suitable elements. We propose a semi-automatic method for generating conforming hexahedral meshes directly from contours segmented from medical images. Magnetic resonance images are generated using a protocol developed to give the abdominal aorta high contrast against the surrounding soft tissue. These data allow us to distinguish between the different structures of interest. We build novel quadrilateral meshes for each surface of the sectioned geometry and generate conforming hexahedral meshes by combining the quadrilateral meshes. The three-layered morphology of both the arterial wall and thrombus is incorporated using parameters determined from experiments. We demonstrate the quality of our patient-specific meshes using the element Scaled Jacobian. The method efficiently generates high-quality elements suitable for FE analysis, even in the bifurcation region of the aorta into the iliac arteries. For example, hexahedral meshes of up to 125,000 elements are generated in less than 130 s, with 94.8 % of elements well suited for FE analysis. We provide novel input for simulations by independently meshing both the arterial wall and intraluminal thrombus of the aneurysm, and their respective layered morphologies.


Subject(s)
Aortic Aneurysm, Abdominal/diagnosis , Thrombosis/diagnosis , Algorithms , Aorta/pathology , Aortic Aneurysm, Abdominal/pathology , Computer Simulation , Finite Element Analysis , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Software , Thrombosis/pathology
16.
J Anim Sci ; 92(1): 129-40, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24352966

ABSTRACT

Intramuscular fat is an important quality trait in pork. Lysine and protein have been reported to influence this trait, but most studies have modified both factors simultaneously. In this study, the effects of dietary Lys and protein were investigated in finishing pigs to determine if either of the 2 factors alone or in combination influence the deposition of intramuscular fat. One hundred and four barrows (Landrace × Duroc) were fed 1 of 4 experimental diets, including control protein-control Lys (CPCL), control protein-low Lys (CPLL), low protein-control Lys (LPCL), and low protein-low Lys diets (LPLL) with 10 pens per treatment and 2 or 3 pigs per pen. Pigs fed CPLL showed a trend to decrease feed efficiency (P < 0.10) compared with those fed CPCL, but pigs fed LPLL performed similarly to the CPCL pigs, indicating that CP levels can be reduced to 12% for pigs between 62 and 97 kg and to 9.8% afterward without negative effects on performance. In the longissimus thoracis, intramuscular fat increased in pigs fed LPCL or CPLL (P < 0.05) compared with CPCL. In the semimembranosus muscle, intramuscular fat was reduced in pigs fed LPLL compared with those fed CPLL (P < 0.05), and the same trend was observed in the longissimus thoracis (P < 0.10). Dietary protein reduction tended to increase back fat thickness (P < 0.10) and reduced SFA and MUFA (P < 0.05) and PUFA, particularly in subcutaneous fat (P < 0.05), whereas the effect on MUFA in the longissimus thoracis was less pronounced. A reduction of n-3 FA (P < 0.05) and PUFA (P < 0.01) in the semimembranosus muscle and in the liver, respectively, was observed when the level of dietary protein was reduced. These results indicate that the effect of a reduction of dietary protein and Lys on growth and intramuscular fat is not independent, and reduction of protein, while maintaining Lys, may improve meat quality without impairing performance.


Subject(s)
Adipose Tissue/metabolism , Dietary Proteins/metabolism , Lysine/metabolism , Muscle, Skeletal/physiology , Sus scrofa/physiology , Animal Feed/analysis , Animal Nutritional Physiological Phenomena/drug effects , Animals , Body Composition/drug effects , Diet/veterinary , Fatty Acids/metabolism , Lipid Metabolism/drug effects , Male , Random Allocation , Sus scrofa/growth & development
17.
J Chem Ecol ; 39(3): 398-412, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23475221

ABSTRACT

Prescribed burning (PB) is gaining popularity as a low-cost forest protection measure that efficiently reduces fuel build-up, but its effects on tree health and growth are poorly understood. Here, we evaluated the impact of PB on plant defenses in Mediterranean pine forests (Pinus halepensis and P. nigra ssp. laricio). These chemical defenses were estimated based on needle secondary metabolites (terpenes and phenolics including flavonoids) and discussed in terms of chlorophyll fluorescence and soil nutrients. Three treatments were applied: absence of burning (control plots); single burns (plots burned once); and repeated burns (plots burned twice). For single burns, we also explored changes over time. In P. laricio, PB tended to trigger only minor modifications consisting exclusively of short-lived increases (observed within 3 months after PB) in flavonoid index, possibly due to the leaf temperature increase during PB. In P. halepensis, PB had detrimental effects on physiological performance, consisting of (i) significant decreases in actual PSII efficiency (ΦPSII) in light-adapted conditions after repeated PB, and (ii) short-lived decreases in variable-to-maximum fluorescence ratio (Fv/Fm) after single PB, indicating that PB actually stressed P. halepensis trees. Repeated PB also promoted terpene-like metabolite production, which increased 2 to 3-fold compared to control trees. Correlations between terpene metabolites and soil chemistry were found. These results suggest that PB impacts needle secondary metabolism both directly (via a temperature impact) and indirectly (via soil nutrients), and that these impacts vary according to species/site location, frequency and time elapsed since last fire. Our findings are discussed with regard to the use of PB as a forest management technique and its consequences on plant investment in chemical defenses.


Subject(s)
Conservation of Natural Resources/methods , Fires , Pinus/metabolism , Plant Leaves/metabolism , Secondary Metabolism , Pinus/growth & development , Soil/chemistry , Terpenes/metabolism , Trees/growth & development
18.
Med Phys ; 39(10): 6351-9, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23039671

ABSTRACT

PURPOSE: Accurate delineation of the rectum is of high importance in off-line adaptive radiation therapy since it is a major dose-limiting organ in prostate cancer radiotherapy. The intensity-based deformable image registration (DIR) methods cannot create a correct spatial transformation if there is no correspondence between the template and the target images. The variation of rectal filling, gas, or feces, creates a non correspondence in image intensities that becomes a great obstacle for intensity-based DIR. METHODS: In this study the authors have designed and implemented a semiautomatic method to create a rectum mask in pelvic computed tomography (CT) images. The method, that includes a DIR based on the demons algorithm, has been tested in 13 prostate cancer cases, each comprising of two CT scans, for a total of 26 CT scans. RESULTS: The use of the manual segmentation in the planning image and the proposed rectum mask method (RMM) method in the daily image leads to an improvement in the DIR performance in pelvic CT images, obtaining a mean value of overlap volume index = 0.89, close to the values obtained using the manual segmentations in both images. CONCLUSIONS: The application of the RMM method in the daily image and the manual segmentations in the planning image during prostate cancer treatments increases the performance of the registration in presence of rectal fillings, obtaining very good agreement with a physician's manual contours.


Subject(s)
Image Processing, Computer-Assisted/methods , Pelvis/diagnostic imaging , Rectum/metabolism , Tomography, X-Ray Computed/methods , Humans , Male , Prostatic Neoplasms/diagnostic imaging , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/radiotherapy , Rectum/diagnostic imaging
19.
J Anim Sci ; 90 Suppl 4: 340-2, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23365373

ABSTRACT

The aim of this study was to investigate underlying mechanisms of dietary conjugated linoleic acid (CLA) on lipid metabolism in various tissues of pigs. Sixteen gilts (73 ± 3 kg) were fed a control (containing sunflower oil) or an experimental diet in which 4% of sunflower oil was replaced by CLA, and slaughtered at an average BW of 117 ± 4.9 kg. Transcription of peroxisome proliferator-activated receptor alpha (PPARα), peroxisome proliferator-activated receptor gamma (PPARγ), fatty acid synthase (FAS), sterol regulatory element binding protein (SREBP1), acetyl-CoA carboxylase (ACC), lipoprotein lipase (LPL), delta-6-desaturase (D6D), and stearoyl CoA desaturase (SCD) were determined by real-time PCR in longissimus thoracis (LT) and semimembranosus (SM) muscles, LT subcutaneous and SM intermuscular fat, and in the liver. Fatty acid (FA) composition was analyzed using gas chromatography in these tissues, except for SM intermuscular fat. Dietary CLA increased PPARγ in LT muscle (P < 0.05), whereas CLA reduced PPARα transcription in all tissues studied (P < 0.05) with the exception of intermuscular fat. Transcription of genes related to FA synthesis was reduced by CLA in SM muscle and liver (SREBP1, both P < 0.1; ACC, P < 0.01 in SM; and FAS, P < 0.01 in liver), whereas CLA reduced (P < 0.05) LPL and D6D transcriptions in SM muscle and reduced (P < 0.05) SCD in liver but increased (P < 0.05) SCD in LT muscle and intermuscular fat. Saturated FA were increased in all studied tissues (P < 0.01), while monosaturated and polyunsaturated FA were reduced in a tissue-specific way by CLA. It was concluded that dietary CLA affected transcription of genes and fat metabolism in a tissue-specific manner.


Subject(s)
Adipose Tissue/drug effects , Gene Expression Regulation/drug effects , Linoleic Acids, Conjugated/pharmacology , Liver/drug effects , Muscle, Skeletal/drug effects , Swine/physiology , Adipose Tissue/metabolism , Animal Feed/analysis , Animal Nutritional Physiological Phenomena , Animals , Diet/veterinary , Dietary Supplements , Female , Liver/metabolism , Muscle, Skeletal/metabolism , Plant Oils , Sunflower Oil
20.
Med Phys ; 37(3): 1137-45, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20384249

ABSTRACT

PURPOSE: Current radiotherapy is progressing to the concept of adaptive radiotherapy, which implies the adaptation of planning along the treatment course. Nonrigid registration is an essential image processing tool for adaptive radiotherapy and image guided radiotherapy, and the three-dimensional (3D) nature of the current radiotherapy techniques requires a 3D quantification of the registration error that existing evaluation methods do not cover appropriately. The authors present a method for 3D evaluation of nonrigid registration algorithms' performance, based on organ delineations, capable of working with near-spherical volumes even in the presence of concavities. METHODS: The evaluation method is composed by a volume shape description stage, developed using a new ad hoc volume reconstruction algorithm proposed by the authors, and an error quantification stage. The evaluation method is applied to the organ delineations of prostate and seminal vesicles, obtained by an automatic segmentation method over images of prostate cancer patients treated with intensity modulated radiation therapy. RESULTS: The volume reconstruction algorithm proposed has been shown to accurately model complex 3D surfaces by the definition of clusters of control points. The quantification method, inspired by the Haussdorf-Chebysev distance, provides a measure of the largest registration error per control direction, defining a valid metric for concave-convex volumes. Summarizing, the proposed evaluation methodology presents accurate results with a high spatial resolution in a negligible computation time in comparison with the nonrigid registration time. CONCLUSIONS: Experimental results show that the metric selected for quantifying the registration error is of utmost importance in a quantitative evaluation based on measuring distances between volumes. The accuracy of the volume reconstruction algorithm is not so relevant as long as the reconstruction is tight enough on the actual volume of the organ. The new evaluation method provides a smooth and accurate volume reconstruction for both the reference and the registered organ, and a complete 3D description of nonrigid registration algorithms' performance, resulting in a useful tool for study and comparison of registration algorithms for adaptive radiotherapy.


Subject(s)
Algorithms , Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Radiotherapy, Computer-Assisted/methods , Radiotherapy, Conformal/methods , Tomography, X-Ray Computed/methods , Image Enhancement/methods , Reproducibility of Results , Sensitivity and Specificity
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