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4.
Sci Total Environ ; 601-602: 1147-1159, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28599371

RESUMEN

Land cover is one of the most important conditioning factors in landslide susceptibility analysis. Usually it is considered as a static factor, but it has proven to be dynamic, with changes occurring even in few decades. In this work the influence of land cover changes on landslide susceptibility are analyzed for the past and for future scenarios. For the application, an area representative of the hilly-low mountain sectors of the Italian Southern Apennines was chosen (Rivo basin, in Molise Region). With this purpose landslide inventories and land cover maps were produced for the years 1954, 1981 and 2007. Two alternative future scenarios were created for 2050, one which follows the past trend (2050-trend), and another one more extreme, foreseeing a decrease of forested and cultivated areas (2050-alternative). The landslide susceptibility analysis was performed using the Spatial Multi-Criteria Evaluation method for different time steps, investigating changes to susceptibility over time. The results show that environmental dynamics, such as land cover change, affect slope stability in time. In fact there is a decrease of susceptibility in the past and in the future 2050-trend scenario. This is due to the increase of forest or cultivated areas, that is probably determined by a better land management, water and soil control respect to other land cover types such as shrubland, pasture or bareland. Conversely the results revealed by the alternative scenario (2050-alternative), show how the decrease in forest and cultivated areas leads to an increase in landslide susceptibility. This can be related to the assumed worst climatic condition leading to a minor agricultural activity and lower extension of forested areas, possibly associated also to the effects of forest fires. The results suggest that conscious landscape management might contribute to determine a significant reduction in landslide susceptibility.

5.
Infez Med ; 17(1): 24-7, 2009 Mar.
Artículo en Italiano | MEDLINE | ID: mdl-19359821

RESUMEN

Voriconazole is used for treating invasive Aspergillosis, Fusarium and Scedosporium infections as well as resistant candidiasis. It is referred to as a second generation triazole. The purpose of this study was to evaluate the concordance of the results of antifungal voriconazole susceptibility tests for yeast isolates, comparing the Sensititre YeastOne method, Atb Fungus 3 and Etest. In all, 138 yeast isolates (42 C. tropicalis, 36 C. glabrata, 14 C. albicans, 8 C. famata, 6 C. parapsilosis, 4 C. dubliniensis, 3 C. krusei, 3 C. lusitaniae, 2 C. zeylanoides, 20 Candida spp.) were tested for susceptibility to amphotericin B, flucytosine, fluconazole , itraconazole and voriconazole with Atb Fungus 3 method. The concordance between the Sensititre YeastOne method, Atm Fungus 3 and Etest for voriconazole was high (90%).


Asunto(s)
Antifúngicos/farmacología , Candida/efectos de los fármacos , Pirimidinas/farmacología , Triazoles/farmacología , Anfotericina B/farmacología , Candida/aislamiento & purificación , Candidiasis/microbiología , Farmacorresistencia Fúngica , Farmacorresistencia Fúngica Múltiple , Fluconazol/farmacología , Flucitosina/farmacología , Humanos , Itraconazol/farmacología , Pruebas de Sensibilidad Microbiana , Especificidad de la Especie , Voriconazol
6.
Int J Artif Organs ; 29(1): 142-52, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16485250

RESUMEN

Peritoneal dialysis (PD) represents a treatment opportunity for patients with end-stage renal failure, but it has particular complications that sometimes force cessation of this procedure (1- 9). These complications are due to the presence of the peritoneal catheter and of dialysis solution within the peritoneal cavity. Infections are the most common complications of PD, followed by mechanical complications. Diagnostic imaging of the complications of PD is important because such an evaluation can aid in the diagnosis and in the decision making process about the treatment. In this review we present the main radiologic investigations employed: plain radiograph, US, peritoneography, computed tomography peritoneography, magnetic resonance peritoneography, peritoneal scintigraphy. To diagnose catheter-related problems plain radiograph, ultrasonography and peritoneography can be useful. US is useful in diagnosing and following-up exit-site and tunnel infections. Peritoneography and CT-peritoneography, alone or in combination, can be recommended as gold standard investigation to assess mechanical peritoneal dialysis complications, such as catheter malfunction, leaks, hernias and sclerosing peritonitis. Newer methods, such as MR peritoneography or scintigraphy could be useful in selected patients, on center-based experience. An appropriate use of radiology may significantly improve technique survival, morbidity and mortality of patients treated with PD.


Asunto(s)
Catéteres de Permanencia/efectos adversos , Diálisis Peritoneal/efectos adversos , Abdomen/diagnóstico por imagen , Abdomen/patología , Humanos , Cavidad Peritoneal/diagnóstico por imagen , Cavidad Peritoneal/patología , Radiografía Abdominal , Ultrasonografía
7.
Am J Kidney Dis ; 38(2): 240-8, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11479148

RESUMEN

In idiopathic membranous nephropathy (MN), the main predictors for progression to chronic renal failure (CRF) are the amount of proteinuria and extent of tubulointerstitial damage. The aim of this study is to evaluate whether urinary excretion of proteins reflecting the alteration of permselectivity in the glomerular capillary wall, such as immunoglobulin G (IgG), and the reabsorption impairment of low-molecular-weight proteins, such as alpha(1)-microglobulin (alpha(1)m), correlates with the extent of tubulointerstitial damage and have a predictive value for functional outcome and response to therapy better than 24-hour proteinuria. In 78 patients with MN, urinary excretion of albumin, transferrin, IgG, and alpha(1)m was measured by immunonephelometry in second-morning urine samples and expressed in milligrams per gram of urinary creatinine (uCr). In 48 patients with characterization of proteinuria and renal biopsy performed at the same time, excretion of IgG (P = 0.0087) and alpha(1)m (P = 0.0024), but not albumin (P = 0.37), transferrin (P = 0.38), or 24-hour proteinuria (P = 0.32), was associated significantly with the extent of tubulointerstitial damage (score, 0 to 1 versus >/=2). Only alpha(1)m excretion was associated significantly with global glomerular sclerosis (P = 0.0032) and arteriolar hyalinosis (P = 0.0004). Moreover, urinary excretion of alpha(1)m was significantly dependent on IgG excretion (r = 0.67; P = 0.0001), but not on albumin (P = 0.66) or 24-hour proteinuria (P = 0.07). Functional outcome could be evaluated in 38 patients with nephrotic syndrome and baseline normal renal function (serum creatinine, 0.99 +/- 0.20 mg/dL; follow-up, 44 +/- 22 months). Remission was 100% versus 20% in patients with IgG excretion less than 110 mg/g uCr versus 110 mg/g uCr or greater (P = 0.0001) and 77% versus 17% in patients with alpha(1)m excretion less than 33.5 mg/g uCr versus 33.5 mg/g uCr or greater (P = 0.0009), respectively. In patients with IgG and alpha(1)m excretion less than or greater than the cutoff value, progression to CRF was 0% versus 35% (P = 0.0026) and 0% versus 58% (P = 0.0001), respectively. Nineteen patients treated with immunosuppressive therapy were compared with 19 untreated patients. There was no difference in remission or progression between treated and untreated patients when IgG and alpha(1)m excretion were less than the cutoff value. There was a significant difference for progression to CRF between treated and untreated patients when alpha(1)m excretion was greater than the cutoff value (17% versus 100%; P = 0.0076). In conclusion, IgG excretion is associated significantly with the extent of tubulointerstitial damage and alpha(1)m excretion. This observation supports the hypothesis that IgG may be the toxic moiety of proteinuria. Excretion of IgG and alpha(1)m has a significant predictive value for both remission and progression and is useful to identify patients who are at risk for progression and for whom treatment with immunosuppressive therapy is indicated soon after diagnosis.


Asunto(s)
alfa-Globulinas/orina , Glomerulonefritis Membranosa/complicaciones , Glomerulonefritis Membranosa/orina , Inmunoglobulina G/orina , Proteinuria/etiología , Albuminuria/diagnóstico , Albuminuria/etiología , Biopsia , Creatinina/sangre , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Glomerulonefritis Membranosa/patología , Humanos , Terapia de Inmunosupresión , Riñón/patología , Fallo Renal Crónico/diagnóstico , Fallo Renal Crónico/etiología , Fallo Renal Crónico/prevención & control , Glomérulos Renales/patología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Proteinuria/diagnóstico , Proteinuria/terapia , Inducción de Remisión , Sensibilidad y Especificidad , Transferrina/orina , Resultado del Tratamiento
8.
J Org Chem ; 65(2): 322-31, 2000 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-10813937

RESUMEN

Electrophilic and electrostatic catalysis have been identified as distinct contributions that affect the reactivity of radical anions in the reductive cleavage of alkyl aryl ethers. Two modes of mesolytic scission of these radical anions are possible: homolytic (dealkylation, a thermodynamically favored but kinetically forbidden process) and heterolytic (dealkoxylation). From our studies (alkali metal reductions, electrochemical studies, use of substrates with a preformed positive charge in certain positions of their structure) it can be concluded that the heterolytic scission is very much dependent on the electrophilic assistance by the counterion and it is only observed in contact ionic pairs with unsaturated cations (electrophilic catalysis). On the other hand, the homolytic scission is observed in solvent-separated ionic pairs, and it is especially efficient when the pair has a controlled topology with a tetralkylammonium cation (saturated cation) near the oxygen atom. The effect of the cation has, in this case, electrostatic origin (electrostatic catalysis), probably lowering the barrier of the intramolecular pi-sigma electron transfer process and thus reducing the kinetic control of the reaction in such a way that the thermodynamically more favorable process is produced.

9.
Diabetes Metab Res Rev ; 15(3): 181-5, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10441040

RESUMEN

BACKGROUND: Intensive insulin therapy is the gold standard by which Type 1 diabetes is treated. In addition to this therapy, administration of nicotinamide (NA) can be beneficial. This concept is reinforced by the results of a recent meta-analysis of the use of NA in patients with recent-onset Type 1 diabetes. METHODS: In this study we compared two different doses of NA in 74 patients with duration of Type 1 diabetes <4 weeks (mean age 13 years). Patients were randomly allocated in blind to two treatment groups: 38 patients received a dose of 25 mg/kg (b.w.) of NA and 36 patients received a dose of 50 mg/kg (b.w.) of NA. Intensive insulin therapy was carried out in order to optimize metabolic control as soon as possible after diagnosis and to maintain blood glucose level as near to normal as possible. Response to therapy was monitored throughout the study by investigating the occurrence of clinical (complete) remission defined, according to the recommendations of the International Diabetes Immunotherapy Group, as restoration of normal fasting and post-prandial blood glucose without any insulin administration for more than 2 weeks. Moreover, the integrated measures of metabolic control (C-peptide, HbA(1c) and insulin dose) were analysed at 3- month intervals up to 1 year after diagnosis. RESULTS: There were no significant differences in the integrated measures of metabolic control between the two NA treated groups either at onset of the disease or at each 3-month interval up to 1 year after diagnosis, although there was a tendency toward higher insulin dosages in the 50 mg NA group. No significant differences were observed in the rate of clinical remission between the two groups. CONCLUSION: We conclude that patients with recent-onset Type 1 diabetes treated with two different doses of NA, in addition to intensive insulin therapy, show similar residual beta-cell function 1 year later. Since both doses of NA are likely to be effective in reducing beta-cell dysfunction, the smaller dose of 25 mg/kg NA would be sufficient as a higher dose may induce insulin resistance.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Niacinamida/administración & dosificación , Niacinamida/uso terapéutico , Adolescente , Adulto , Niño , Preescolar , Diabetes Mellitus Tipo 1/metabolismo , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/uso terapéutico , Insulina/administración & dosificación , Insulina/uso terapéutico , Masculino , Niacinamida/efectos adversos , Tamaño de la Muestra , Resultado del Tratamiento
10.
J Vasc Surg ; 26(5): 796-802, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9372817

RESUMEN

PURPOSE: In spite of its invasiveness, measurement of ambulatory venous pressure (AVP) is widely considered the gold standard measurement of venous function. We studied a technique for noninvasive ultrasonographic AVP determination in superficial venous incompetence. METHODS: A linear relationship between venous pressure (measured by echo-guided venous puncture) and diameter (measured by transverse axis duplex imaging) was preliminarily demonstrated with multiple measurements in different conditions (supine, sitting, standing, and Trendelenburg positions, after exercise with and without cuff occlusion) in a saphenous tract at the thigh of 82 limbs in which reflux had been previously demonstrated. Then AVP was measured in another group of 44 patients who had demonstrated superficial venous incompetence, both with and without proximal occlusion, using again the same invasive method and a new noninvasive technique. The latter technique consisted in the construction of a linear diameter/pressure curve obtained after saphenous diameter (by high-resolution sonography) and noninvasive pressure (using hydrostatic values) determinations in the sitting and standing positions. Further measurement of saphenous diameter after standardized exercise permits extrapolation of the AVP values from the curve. RESULTS: Linear regression analysis demonstrates that (1) beginning from 20 mm Hg, the pressure/diameter relationship of the incompetent greater saphenous vein is linear; and (2) AVP values derived invasively and noninvasively are significantly correlated (r = 0.7347 and p < 0.0001 for AVP derived without occlusion; r = 0.7270 and p < 0.0001 for values recorded with occlusion). CONCLUSIONS: The proposed technique appears able to reliably assess noninvasively AVP values in superficial venous incompetence. In addition, it can be performed with equipment that is widely used for vascular investigations.


Asunto(s)
Ejercicio Físico , Insuficiencia Venosa/diagnóstico por imagen , Presión Venosa , Femenino , Humanos , Masculino , Persona de Mediana Edad , Postura , Vena Safena/fisiopatología , Ultrasonografía , Insuficiencia Venosa/fisiopatología
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