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1.
Ann Surg ; 278(6): e1204-e1209, 2023 12 01.
Article in English | MEDLINE | ID: mdl-37051926

ABSTRACT

OBJECTIVE: To assess the frequency of occult metastases (OM) in patients with resected pancreatic ductal adenocarcinoma (PDAC) or ampullary adenocarcinoma (AA) discovered on detailed pathologic examination on lymph nodes (LNs) previously considered negative by conventional analysis and to examine the association between OM and overall survival (OS). BACKGROUND: Poor prognosis of patients with no pathologic evidence of LN metastases may be due to OM that is not detected on conventional LN analysis. METHODS: Patients with LN-negative resected PDAC or AA (2010-2020) were identified from our institutional database. Original hematoxylin and eosin ( H and E ) slides were reanalyzed. In addition, selected LN were analyzed by H and E (3 sections/LN) and pan-cytokeratin (AE1-AE3/PCK26) immunohistochemistry. RESULTS: A total of 598 LNs from 74 LN-negative patients were reexamined. Nineteen patients (25.7%) had OM; 9 (47.4%) were found with immunohistochemistry but not on H and E . The number of positive LNs ranged from 1 to 3. No clinicodemographic, pathologic, or treatment-related factors were associated with OM. On conventional LN analysis, 3/19 patients (15.8%) had stage IA, 9/34 (26.5%) had stage IB, and 7/19 (36.8%) had stage IIA. On detailed LN analysis, 11/19 patients (57.9%) were upstaged to IIB, whereas 8/19 (42.1%) had isolated tumor cells only (N0i+). OM was associated with shorter OS (median OS: 22.3 vs 50.5 months; hazard ratio=3.95, 95% CI: 1.58-9.86). CONCLUSIONS: There is a 26% discordance rate between conventional and detailed LN pathologic analysis in resected PDAC and AA. The presence of OM is associated with shorter OS.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Humans , Prognosis , Neoplasm Staging , Retrospective Studies , Lymph Nodes/pathology , Lymph Node Excision , Carcinoma, Pancreatic Ductal/surgery , Carcinoma, Pancreatic Ductal/pathology , Pancreatic Neoplasms
2.
Brain ; 138(Pt 4): 1009-22, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25688081

ABSTRACT

Genetic and environmental factors that increase the risk of late-onset Alzheimer disease are now well recognized but the cause of variable progression rates and phenotypes of sporadic Alzheimer's disease is largely unknown. We aimed to investigate the relationship between diverse structural assemblies of amyloid-ß and rates of clinical decline in Alzheimer's disease. Using novel biophysical methods, we analysed levels, particle size, and conformational characteristics of amyloid-ß in the posterior cingulate cortex, hippocampus and cerebellum of 48 cases of Alzheimer's disease with distinctly different disease durations, and correlated the data with APOE gene polymorphism. In both hippocampus and posterior cingulate cortex we identified an extensive array of distinct amyloid-ß42 particles that differ in size, display of N-terminal and C-terminal domains, and conformational stability. In contrast, amyloid-ß40 present at low levels did not form a major particle with discernible size, and both N-terminal and C- terminal domains were largely exposed. Rapidly progressive Alzheimer's disease that is associated with a low frequency of APOE e4 allele demonstrates considerably expanded conformational heterogeneity of amyloid-ß42, with higher levels of distinctly structured amyloid-ß42 particles composed of 30-100 monomers, and fewer particles composed of < 30 monomers. The link between rapid clinical decline and levels of amyloid-ß42 with distinct structural characteristics suggests that different conformers may play an important role in the pathogenesis of distinct Alzheimer's disease phenotypes. These findings indicate that Alzheimer's disease exhibits a wide spectrum of amyloid-ß42 structural states and imply the existence of prion-like conformational strains.


Subject(s)
Alzheimer Disease/genetics , Alzheimer Disease/pathology , Amyloid beta-Peptides/genetics , Disease Progression , Peptide Fragments/genetics , Adult , Aged , Aged, 80 and over , Cohort Studies , Female , Humans , Male , Middle Aged , Time Factors
3.
ScientificWorldJournal ; 2014: 806959, 2014.
Article in English | MEDLINE | ID: mdl-25114973

ABSTRACT

The amount of water on earth is the same and only the distribution and the reallocation of water forms are altered in both time and space. To improve the rainwater harvesting a better understanding of the hydrological cycle is mandatory. Clouds are major component of the hydrological cycle; therefore, clouds distribution is the keystone of better rainwater harvesting. Remote sensing technology has shown robust capabilities in resolving challenges of water resource management in arid environments. Soil moisture content and cloud average distribution are essential remote sensing applications in extracting information of geophysical, geomorphological, and meteorological interest from satellite images. Current research study aimed to map the soil moisture content using recent Landsat 8 images and to map cloud average distribution of the corresponding area using 59 MERIS satellite imageries collected from January 2006 to October 2011. Cloud average distribution map shows specific location in the study area where it is always cloudy all the year and the site corresponding soil moisture content map came in agreement with cloud distribution. The overlay of the two previously mentioned maps over the geological map of the study area shows potential locations for better rainwater harvesting.


Subject(s)
Rain , Remote Sensing Technology , Water Cycle , Conservation of Natural Resources , Geography , Saudi Arabia
4.
Article in English | MEDLINE | ID: mdl-32899595

ABSTRACT

Land Cover monitoring is an essential task for a better understanding of the ecosystem's dynamicity and complexity. The availability of Remote Sensing data improved the Land Use Land Cover mapping as it is routine work in ecosystem management. The complexity of the Mediterranean ecosystems involves a complexity of the surrounding environmental factors. An attempt to quantitatively investigate the interdependencies between land covers and affected environmental factors was conducted in Nisos Elafonisos to represent diverse and fragile coastal Mediterranean ecosystems. Sentinel-2 (MSI) sensor and ASTER Digital Elevation Model (DEM) data were used to classify the LULC as well as to draw different vegetation conditions over the designated study area. DEM derivatives were conducted and incorporated. The developed methodology is intended to assess the land use land cover for different practices under the present environmental condition of Nisos Elafonisos. Supervised classification resulted in six different land cover clusters and was tested against three different environmental clusters. The findings of the current research pointed out that the environmental variables are independent and there is a vertical distribution of the vegetation according to altitude.


Subject(s)
Ecosystem , Environmental Monitoring , Agriculture , Altitude , Conservation of Natural Resources , Greece
5.
Saudi J Biol Sci ; 27(11): 3169-3179, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33100880

ABSTRACT

Accurate and up to date land use and land cover (LU/LC) changes information is the main source to understanding and assessing the environmental outcomes of such changes and is important for development plans. Thus, this study quantified the outlines of land cover variation of 10-years in the northwestern costal land of the Red Sea, Saudi Arabia. Two different supervised classification algorithms are visualized and evaluated to preparing a policy recommendation for the proper improvements towards better determining the tendency and the proportion of the vegetation cover changes. Firstly, to determine present vegetation structure of study area, 78 stands with a size of 50 × 50 m were analysed. Secondly, to obtain the vegetation dynamics in this area, two satellite images of temporal data sets were used; therefore, SPOT-5 images were obtained in 2004 and 2013. For each data set, four SPOT-5 scenes were placed into approximately 250-km intervals to cover the northwestern coastal land of the Red Sea. Both supervised and non-supervised cataloguing methods were attained towards organise the study area in 4-major land cover classes through using 5 various organizations algorithms. Approximately 900 points were evenly distributed within each SPOT-5 image and used for assessment accuracy. The floristic composition exhibits high diversity with 142 species and seven vegetation types were identified after multivariate analysis (VG I: Acacia tortilis-Acacia ehrenbergiana, VG II: Acacia tortilis-Stipagrostis plumosa, VG III: Zygophyllum coccineum-Zygophyllum simplex, VG IV: Acacia raddiana-Lycium shawii-Anabasis setifera, VG V: Tamarix aucheriana-Juncus rigidus, VG VI: Capparis decidua-Zygophyllum simplex and VG VII: Avicennia marina-Aristida adscensionis) and ranged between halophytic vegetation on the coast to xerophytic vegetation with scattered Acacia trees inland. The dynamic results showed rapid, imbalanced variations arises between 3-land cover classes (areas as urban, vegetation and desert). However, these findings shall serve as the baseline data for the design of rehabilitation programs that conserve biodiversity in arid regions and form treasured resources for an urban planner and decision makers to device bearable usage of land and environmental planning.

6.
Environ Sci Pollut Res Int ; 26(35): 35377-35386, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31168717

ABSTRACT

The current study observes the input/output energy quantities and its associated financial value, in vegetable greenhouses on Crete, Greece, for the 2015-2016 cropping seasons. The utilized data was taken in regular direct basis for the implementation of energy input-output analysis and data envelopment analysis. For input data analysis, four crop practices were used tomato, pepper, cucumber, and eggplant. The outcomes of the expended majority of energy input-output analysis showed that fertilizers count for 53%, fossil fuel counts for 16%, and electricity counts for 12%. The mean crop and energy consumption for each crop practice were estimated as 94,036 MJ/ha and 171,950 kg/ha, 115,473 MJ/ha and 173,000 kg/ha, 81,196 MJ/ha and 128,893 kg/ha, and 146,067 MJ/ha and 209,501 kg/ha, respectively. Inputs with the biggest shares in total inputs were manpower counts for 30%, fertilizers count for 22%, and crop protection counts for 16%. DEA method showed that the mean values of technical efficiency, pure technical efficiency, and scale efficiency were 0.90193, 0.97272, and 0.80322, respectively. The mean scale efficiencies were set as 0.80. The findings of this research would be valuable to the inefficient producers undertaking into consideration the recommendations made by this method, where the overall input in Euro could be meaningfully condensed without any reduction on the current overall output.


Subject(s)
Data Analysis , Fertilizers/analysis , Agriculture/methods , Crops, Agricultural/growth & development , Greece , Islands
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