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1.
Environ Monit Assess ; 191(8): 482, 2019 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-31273536

RESUMEN

Hydrological indices provide excellent input to geographic information systems for the successful mapping of erosion-prone areas. In this research, a digital elevation model was processed and analyzed to obtain the necessary hydrological indices necessary for erosion modeling. The indices (such as sediment transport index, compound topography index, and stream power index) along with other themes (Like Slope gradient, curvature, distance to channels, and channel density) were overlaid using the "Weighted Sum" overlay tool in the geographic information system. The results showed that 33.14 km2 of the test watershed (sub-basin of Abay, Ethiopia) falls in very high/severe erosion zone and needs immediate conservation measures. A total of 98.26 km2, 153.40 km2, and 263.17 km2 fall in high-, moderate-, and low-erosion hazard zones, respectively. Therefore, the primary and secondary derivatives of the digital elevation model along with morphometric parameters coupled with a Spatial Analyst tool proves to be a powerful integrated approach in demarcating erosion vulnerable zones and could be applied at regional and continental scale for proper watershed management.


Asunto(s)
Monitoreo del Ambiente/métodos , Programas Informáticos , Conservación de los Recursos Naturales , Etiopía , Sistemas de Información Geográfica , Sedimentos Geológicos , Hidrología , Ríos , Suelo
2.
Sci Total Environ ; 855: 158845, 2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36122722

RESUMEN

Inland saline waters in Central Asia constitute an important part of steppe ecosystems, providing considerable ecological functions and ecosystem services. Here we aim to present a multi-spatial scale analysis of nutrient cycling and transport waterbird guilds, and the environmental attributes of saline-soda aquatic ecosystems in Kazakhstan. The density, biomass, and diversity of waterbird guilds was determined in the case of three nutrient cycling and transport guilds: a) net-importer (IM), b) importer-exporter (IMEX), c) net-exporter (EX), according to the Boros's guild classification method, and for several traditional feeding guilds: carnivorous, herbivorous, invertebrate eater, omnivorous and piscivorous. Our results revealed that waterbird guilds, as predictors represented by the complete waterbird community, are in close relationship with several (N = 12) environmental attributes of inland saline waters through complex trophic linkages of waterbird populations on multi-spatial scales. The density and the biomass of the EX and IMEX guilds are strongly and positively correlated (i) with the productivity metrics of habitats (e.g., CHL, GPP), indicating their trophic position, and (ii) with water depth. We found significant correlations among guild density, biomass, diversity and environmental attributes on multi-spatial scales for IMEX and EX. Our results revealed that IMEX predicts the surrounding environment of aquatic habitats, whereas EX species are substantial environmental predictors of aquatic ecosystems. However, the diversity metric had valid models only with EX. The herbivorous and omnivorous guilds, that feed chiefly on plant materials consist mainly of IMEX and EX duck species, which were positively related to grassland coverage and the shoreline development index. As a methodological result, here we present a novel approach, the guild transport index, which has more robust relationships with environmental attributes than individual guilds, thus it provides a complex evaluation of the nutrient cycling by birds between aquatic and terrestrial environments on multi-spatial scales.


Asunto(s)
Aves , Ecosistema , Animales , Invertebrados , Biomasa , Kazajstán
3.
Pharmaceutics ; 15(12)2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38140073

RESUMEN

Many evaluation tools for predicting human absorption are well-known for using cultured cell lines such as Caco-2, MDCK, and so on. Since the combinatorial chemistry and high throughput screening system, pharmacological assay, and pharmaceutical profiling assay are mainstays of drug development, PAMPA has been used to evaluate human drug absorption. In addition, cultured cell lines from iPS cells have been attracting attention because they morphologically resemble human intestinal tissues. In this review, we used human intestinal tissues to estimate human intestinal absorption and metabolism. The Ussing chamber uses human intestinal tissues to directly assay a drug candidate's permeability and determine the electrophysiological parameters such as potential differences (PD), short circuit current (Isc), and resistance (R). Thus, it is an attractive tool for elucidating human intestinal permeability and metabolism. We have presented a novel prediction method for intestinal absorption and metabolism by utilizing a mini-Ussing chamber using human intestinal tissues and animal intestinal tissues, based on the transport index (TI). The TI value was calculated by taking the change in drug concentrations on the apical side due to precipitation and the total amounts accumulated in the tissue (Tcorr) and transported to the basal side (Xcorr). The drug absorbability in rank order, as well as the fraction of dose absorbed (Fa) in humans, was predicted, and the intestinal metabolism of dogs and rats was also predicted, although it was not quantitative. However, the metabolites formation index (MFI) values, which are included in the TI values, can predict the evaluation of intestinal metabolism and absorption by using ketoconazole. Therefore, the mini-Ussing chamber, equipped with human and animal intestinal tissues, would be an ultimate method to predict intestinal absorption and metabolism simultaneously.

4.
MethodsX ; 10: 102062, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36845367

RESUMEN

Hydrological modelling is a precondition for many scientific researches such as species distribution models, ecological models, agricultural suitability models, climatological models, hydrological models, flood and flash flood models, landslide models etc. Even the topographic control over many hydrological factors has also been studied. Over time different hydrological models have been developed and extensively used. Recently, these models have been used to prepare different types of conditional factors that are widely used in hazard modelling such as floods, flash floods, landslides etc. Quantitative analysis of the Digital Elevation Model (DEM) according to different models by engaging Geographic Information Systems (GIS) supports users to extract various types of information about landscapes where hydrological and topographic information are most important. Methods to prepare hydrological factors namely TWI, TRI, SPI, STI, TPI, stream density and distance to stream by processing DEM in GIS are discussed in this paper. These common hydrological factors are extensively used in many scientific research papers either for modelling or to measure their relationship with other environmental factors.•Hydrological factors have great importance in understanding the landscape and are widely used in scientific research, especially geo-environmental hazard mapping.•Physically based hydrological methods are engaged in ArcMap 10.5 software.•Commonly used hydrological factors are processed using freely available DEM and ArcMap 10.5 software.

5.
J Pharm Sci ; 109(4): 1623-1626, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31870787

RESUMEN

The purpose of this study was to examine drug absorption profile utilizing human intestinal tissues from ulcerative colitis (UC) patients and to compare with normal tissues from intestinal cancer patients. Human intestinal tissues from UC and cancer patients mounted in a mini-Ussing chamber were used to evaluate the permeation of drugs, including FD-4, a very low permeable marker, rebamipide, a low permeable marker, and metoprolol, a high permeable marker. The transport index, an index of sum of permeated and tissue-accumulated molecules, of the model drugs was in accordance with their absorption rank order, and was almost kept constant irrespective of autopsy grade based on tissue fibrosis. On the other hand, UC tissues of grade 2 showed the decreased Xcorr, an index of permeated amount of molecules and increased Tcorr, an index of tissue-accumulated molecules for every tested compound. Our finding of the transport characteristics in intestinal tissues of severe UC patients in mini-Ussing chamber system demonstrated that autopsy grade of UC patients did not drastically change membrane permeability of the tested compounds. Furthermore, it was suggested that morphological changes of intestinal tissues caused by fibrosis led to limited permeation and subsequently increased accumulation with little change of total absorption.


Asunto(s)
Colitis Ulcerosa , Preparaciones Farmacéuticas , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/metabolismo , Humanos , Absorción Intestinal , Mucosa Intestinal/metabolismo , Permeabilidad , Preparaciones Farmacéuticas/metabolismo
6.
Nucl Med Mol Imaging ; 53(1): 47-56, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30828401

RESUMEN

INTRODUCTION: Lymphoscintigraphy is the gold standard for imaging in the diagnosis of peripheral lymphedema. However, there are no clear guidelines to standardize usage across centers, and as such, large variability exists. The aim of this perspectives paper is to draw upon the knowledge and extensive experience of lymphoscintigraphy here in Genoa, Italy, from our center of excellence in the assessment and treatment of lymphatic disorders for over 30 years to provide general guidelines for nuclear medicine specialists. METHOD: The authors describe the technical characteristics of lymphoscintigraphy in patients with limb swelling. Radioactive tracers, dosage, administration sites, and the rationale for a two-compartment protocol with the inclusion of subfascial lymphatic vessels are all given in detail. RESULTS: Examples of lymphoscintigraphic investigations with various subgroups of patients are discussed. The concept of a transport index (TI) for semi-quantitative analysis of normal/pathological lymphatic flow is introduced. Different concepts of injection techniques are outlined. DISCUSSION: It is past time that lymphoscintigraphy in the diagnosis of lymphatic disorders becomes standardized. This represents our first attempt to outline a clear protocol and delineate the relevant points for lymphoscintigraphy in this patient population.

7.
J Pharm Sci ; 108(1): 763-769, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30389567

RESUMEN

The purpose of this study was to investigate the possibility of simultaneous prediction of the intestinal absorption and metabolism in a mini-Ussing chamber equipped with rat intestinal tissues, based on the transport index (TI). TI value was defined as the sum of drug amounts, by mass balance method, transported to the basal-side component and drug amounts accumulated in the tissue, which are normalized by area under the curve of the drug in the apical compartment. Midazolam and nifedipine with high permeability were used as typical P450 substrates to examine the possibility of simultaneous prediction of intestinal absorption and metabolism. The metabolite formation of both compounds was observed and ketoconazole strongly inhibited the metabolite formation of both compounds in rat intestinal tissues, leading to the improvement of the TI value to a statistically significant extent for both compounds. TI ratio of nifedipine between in the presence and absence of ketoconazole was larger than that of midazolam, which was consistent with the reported lower value of fraction absorbed multiplied by intestinal availability of nifedipine. Therefore, the mini-Ussing chamber, equipped with animal intestinal tissues, showed potential to predict the intestinal absorption and metabolism simultaneously.


Asunto(s)
Absorción Intestinal/fisiología , Mucosa Intestinal/metabolismo , Preparaciones Farmacéuticas/metabolismo , Animales , Sistemas de Liberación de Medicamentos/métodos , Cetoconazol/metabolismo , Masculino , Midazolam/metabolismo , Nifedipino/metabolismo , Permeabilidad , Ratas , Ratas Sprague-Dawley
8.
J Plast Reconstr Aesthet Surg ; 72(2): 216-224, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30472046

RESUMEN

INTRODUCTION: Vascularized lymph node transfer is an established treatment for secondary lymphedema. Different donor sites of lymph node flap have been described. In our institute, vascularized groin lymph node (VGLN) flap is the workhorse flap for treating breast cancer-related lymphedema (BCRL). Potential complications of VGLN flap harvesting include seroma formation, thigh dysaesthesia, and iatrogenic lymphedema. METHODS: Between August 2013 and June 2016, 30 consecutive patients with a mean age of 60 years underwent VGLN transfer for BCRL. Reverse mapping of lower limb lymphatics with patent blue solution was performed in all cases. The donor limb conditions were assessed clinically with limb circumference measurement and radiologically with lymphoscintigraphy. Postoperative lymphoscintigraphy findings and transport indexes were compared between the donor and nonoperated limbs. RESULTS: The mean follow-up period was 22.11 ±â€¯7.83 months. Three (10%) patients developed groin seroma and 18 (60%) patients complained of transient thigh dysaesthesia. There was no clinically detectable donor limb lymphedema. Lymphoscintigraphy was performed at a mean of 13 months after operation. The mean transport indexes of the nonoperated limbs and donor limbs were 2.04 and 3.32, respectively. For the donor limbs, all patients had normal distribution pattern of contrast uptake. No dermal backflow pattern was demonstrated. CONCLUSION: With good knowledge of groin anatomy and meticulous surgical skills, VGLN flap can be harvested without causing major consequence to the donor limb.


Asunto(s)
Conducto Inguinal/diagnóstico por imagen , Conducto Inguinal/patología , Ganglios Linfáticos/irrigación sanguínea , Ganglios Linfáticos/trasplante , Linfedema/cirugía , Linfocintigrafia , Colgajos Quirúrgicos/irrigación sanguínea , Sitio Donante de Trasplante/diagnóstico por imagen , Sitio Donante de Trasplante/patología , Anciano , Neoplasias de la Mama/complicaciones , Femenino , Humanos , Linfedema/etiología , Persona de Mediana Edad , Estudios Prospectivos
9.
Artículo en Inglés, Español | MEDLINE | ID: mdl-31196709

RESUMEN

Lymphoscintigraphy represents the "gold standard" for diagnosis of lymphedema, but an important limitation is the lack of procedural standardization. The aim of this Italian expert panel was to provide a procedural standard for lymphoscintigraphy in the evaluation of lymphatic system disorders. Topic anaesthetic gels containing lidocaine should be avoided. Patients should remove compressive dressings. Total recommended activity for 99mTc-nanocolloid administration in adults is 74MBq, or 37MBq per limb and per investigated compartment, in single or multiple aliquots. 2-3 subcutaneous injections should be performed (II-III±I interdigital space of each hand/foot), avoiding intravascular injection. Deep lymphatic system of lower limbs should be evaluated in presence of dermal back-flow or lymphatic stasis (1-2 subfascial administrations in retro-malleolar or plantar region). Planar images should be acquired from injection site to liver with whole-body or serial static acquisitions 20' and 90' after subcutaneous administration. Additional information on lymphatic pathways is obtained after a quick and/or prolonged exercise protocol. SPECT/CT is recommended to study the thoracic, abdominal and pelvic territories. When required, deep lymphatic system of lower limbs should be evaluated with static acquisition 90' after subfascial administration. The report should describe administration and imaging procedure, exercise protocol, qualitative and semi-quantitative analysis (wash-out rate, transport index), potential sources of error. Due to the essential role fulfilled by lymphoscintigraphy in clinical management of primary and secondary lymphedema, an effort for the standardization of this technique should be made to provide the clinicians with a homogeneous and reliable technical methodology.


Asunto(s)
Extremidades/diagnóstico por imagen , Linfedema/diagnóstico por imagen , Linfocintigrafia , Humanos , Guías de Práctica Clínica como Asunto , Informe de Investigación
10.
Eur J Pharm Biopharm ; 122: 49-53, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28974435

RESUMEN

The purpose of this study was to evaluate the intestinal metabolism and absorption in a mini-Ussing chamber equipped with animal intestinal tissues, based on the transport index (TI). TI value was defined as the sum of drug amounts transported to the basal-side component (Xcorr) and drug amounts accumulated in the tissue (Tcorr), which are normalized by AUC of a drug in the apical compartment, as an index for drug absorption. Midazolam was used as a test compound for the evaluation of intestinal metabolism and absorption. The metabolite formulation of midazolam was observed in both rats and dogs. Ketoconazole inhibited the intestinal metabolism of midazolam in rats and improved its intestinal absorption to a statistically significant extent. Therefore, the mini-Ussing chamber, equipped with animal intestinal tissues, showed potential to use the evaluation of the intestinal metabolism and absorption, including the assessment of species differences.


Asunto(s)
Absorción Intestinal/fisiología , Mucosa Intestinal/metabolismo , Cetoconazol/metabolismo , Animales , Transporte Biológico/efectos de los fármacos , Perros , Masculino , Permeabilidad/efectos de los fármacos , Ratas , Ratas Sprague-Dawley
11.
Eur J Pharm Sci ; 96: 373-380, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-27721045

RESUMEN

An adequate evaluation system for drug intestinal absorption is essential in the pharmaceutical industry. Previously, we established a novel prediction system of drug intestinal absorption in humans, using the mini-Ussing chamber equipped with human intestinal tissues. In this system, the TI value was defined as the sum of drug amounts transported to the basal-side component (Xcorr) and drug amounts accumulated in the tissue (Tcorr), which are normalized by AUC of a drug in the apical compartment, as an index for drug absorption. In order to apply this system to the screening assay, it is important to understand the differences between animal and human tissues in the intestinal absorption of drugs. In this study, the transport index (TI) values of three drugs, with different levels of membrane permeability, were determined to evaluate the rank order of drug absorbability in intestinal tissues from rats, dogs, and monkeys. The TI values in small intestinal tissues in rats and dogs showed a good correlation with those in humans. On the other hand, the correlation of TI values in monkeys was lower compared to rats and dogs. The rank order of the correlation coefficient between human and investigated animal tissues was as follows: dog (r2=0.978), rat (r2=0.955), and monkey (r2=0.620). TI values in large intestinal tissues from rats (r2=0.929) and dogs (r2=0.808) also showed a good correlation. The obtained TI values in small intestinal tissues in rats and dogs were well correlated with the fraction of drug absorbed (Fa) in humans. From these results, the mini-Ussing chamber, equipped with intestinal tissues in rats and dogs, would be useful as a screening tool in the drug discovery stage. In addition, the obtained TI values can be used for the prediction of the Fa in humans.


Asunto(s)
Absorción Intestinal/efectos de los fármacos , Absorción Intestinal/fisiología , Animales , Atenolol/metabolismo , Atenolol/farmacología , Transporte Biológico/efectos de los fármacos , Transporte Biológico/fisiología , Cámaras de Difusión de Cultivos , Perros , Predicción , Haplorrinos , Humanos , Masculino , Metoprolol/metabolismo , Metoprolol/farmacología , Ratas , Ratas Sprague-Dawley , Especificidad de la Especie
12.
J Pharm Sci ; 102(8): 2564-71, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23686795

RESUMEN

The objective of this study was to establish a novel prediction system of drug absorption in humans by utilizing human intestinal tissues. Based on the transport index (TI), a newly defined parameter, calculated by taking account of the change in drug concentrations because of precipitation on the apical side and the amounts accumulated in the tissue and transported to the basal side, the absorbability of drugs in rank order as well as the fraction of dose absorbed (Fa) in humans were estimated. Human intestinal tissues taken from ulcerative colitis or Crohn's disease patients were mounted in a mini-Ussing chamber and transport studies were performed to evaluate the permeation of drugs, including FD-4, a very low permeable marker, atenolol, a low permeable marker, and metoprolol, a high permeable marker. Although apparent permeability coefficients calculated by the conventional equation did not reflect human Fa values for FD-4, atenolol, and metoprolol, TI values were well correlated with Fa values, which are described by 100 · [1 - e (- f · (TI - α)) ]. Based on this equation, Fa values in humans for other test drugs were predicted successfully, indicating that our new system utilizing human intestinal tissues would be valuable for predicting oral drug absorption in humans.


Asunto(s)
Antagonistas de Receptores Adrenérgicos beta 1/farmacocinética , Atenolol/farmacocinética , Imidazoles/farmacocinética , Absorción Intestinal , Mucosa Intestinal/metabolismo , Metoprolol/farmacocinética , Éteres Fenílicos/farmacocinética , Adulto , Anciano , Algoritmos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Biológicos , Permeabilidad , Adulto Joven
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