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1.
J Dairy Sci ; 107(7): 4381-4393, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38278298

RESUMEN

The objectives of this retrospective observational study were to investigate the association between BCS at 21 d before calving with prepartum and postpartum DMI, energy balance (EB), and milk yield. Data from 427 multigravid cows from 11 different experiments conducted at the University of Florida (Gainesville, FL) were used. Cows were classified according to their BCS at 21 d before calving as fat (BCS ≥ 4.00; n = 83), moderate (BCS = 3.25-3.75; n = 287), and thin (BCS ≤ 3.00; n = 57). Daily DMI from -21 to -1 and from +1 to +28 DIM was individually recorded. Energy balance was calculated as the difference between net energy for lactation consumed and required. Dry matter intake in fat cows was lower than that in moderate and thin cows both prepartum (fat = 9.97 ± 0.21, moderate = 11.15 ± 0.14, and thin = 11.92 ± 0.22 kg/d) and postpartum (fat = 14.35 ± 0.49, moderate = 15.47 ± 0.38, and thin = 16.09 ± 0.47 kg/d). Dry matter intake was also lower for moderate cows compared with thin cows prepartum, but not postpartum. Energy balance in fat cows was lower than in moderate and thin cows both prepartum (fat = -4.16 ± 0.61, moderate = -1.20 ± 0.56, and thin = 0.88 ± 0.62 Mcal/d) and postpartum (fat = -12.77 ± 0.50, moderate = -10.13 ± 0.29, and thin = -6.14 ± 0.51 Mcal/d). Energy balance was also lower for moderate cows compared with thin cows both prepartum and postpartum. There was a quadratic association between BCS at 21 d before calving and milk yield. Increasing BCS from 2.5 to 3.5 was associated with an increase in daily milk yield of 6.0 kg and 28 d cumulative milk of 147 kg. Increasing BCS from 3.5 to 4.5 was associated with a decrease in daily milk yield of 4.4 kg and 28 d cumulative milk of 116 kg. In summary, a moderate BCS at 21 d before calving was associated with intermediate DMI and EB pre- and postpartum but greater milk yield compared with thinner and fatter cows. Our findings indicate that a moderate BCS is ideal for ensuring a successful lactation.


Asunto(s)
Metabolismo Energético , Lactancia , Leche , Periodo Posparto , Animales , Bovinos , Femenino , Leche/metabolismo , Embarazo , Estudios Retrospectivos , Dieta/veterinaria
2.
Nanotechnology ; 34(32)2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37163999

RESUMEN

The microwave detection capability of GaN-based asymmetric planar nanodiodes (so-called Self-Switching Diode, SSD, due to its non-linearity) has been characterized in a wide temperature range, from 70 K up to 300 K. At low temperature, microwave measurements reveal an enhancement of the responsivity at frequencies below 1 GHz, which, together with a pronounced hysteresis in the DC curves, indicate a significant influence of the surface states. This leads to a significant variability and non-repeatability which needs to be reduced since it degrades the accuracy of the detection. For this sake, the RF characterization was repeated after applying a positive/negative voltage able to fill/empty the surface states in order to have a well-established preconditioned state. As a consequence of the positive pre-soak bias, a significant enhancement of the measured responsivity, with a × 10 increase at low temperature. The RF detection measurements after such preconditioning contains a time dependence induced by the slow discharge mechanism of the traps, so that the improved responsivity remains even after 100s of seconds. On the other hand, a negative voltage pre-soak benefits the discharge process, thus suppressing the low frequency dispersion and the important variability of the detection without the pre-conditioning step. We also show that the relation between the voltage and current responsivities in each case allows to explain the impact of the surface charges in terms of the device impedance.

3.
J Dairy Sci ; 106(11): 8098-8109, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37641346

RESUMEN

The objective of this study was to identify metabolites associated with metritis and use them for identification of cellular mechanisms affected during transition into lactation. Holstein cows (n = 104) had blood collected in the prepartum period (d -14 ± 6 relative to calving), at calving (d 0), and at the day of metritis diagnosis (d 7 ± 2 after calving). Cows with reddish or brownish, watery, and fetid discharge were diagnosed with metritis (n = 52). Cows with metritis were paired with herdmates without metritis (n = 52) based on days in milk. The metabolome of plasma samples was evaluated using untargeted gas chromatography time-of-flight mass spectrometry. Univariate analyses included t-tests and fold change analyses. Metabolites with false discovery rate adjusted P ≤ 0.10 on t-tests were used for partial least squares discriminant analysis coupled with permutational analysis using 2,000 permutations. Metabolites with false discovery rate adjusted P ≤ 0.10 on t-tests were also used for enriched pathway analyses and identification of cellular processes. Cows that developed metritis had affected cellular processes associated with lower amino acid metabolism in the prepartum period, greater lipolysis, cell death, and oxidative stress at calving and at metritis diagnosis, and greater leukocyte activation at calving, but lower immune cell activation at metritis diagnosis. In summary, cows that developed metritis had plasma metabolomic changes associated with greater lipolysis, oxidative stress, and a dysregulated immune response which may predispose cows to metritis development.

4.
J Dairy Sci ; 106(12): 9244-9259, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37641354

RESUMEN

The objective was to unravel the peripartum immune and metabolic changes associated with metritis in Holstein cows. Holstein cows (n = 128) had blood collected at -14, 0, 3, and 7 d relative to parturition (DRP). Flow cytometry was used to evaluate blood leukocyte counts, proportions, and activation. Total cells, live cells, single cells, monocytes (CD172α+/CD14+), polymorphonuclears (CD172α+/CD14-/SSChigh), B-cells (CD21+/MHCII+), CD4+ T-cells (CD4+), CD8+ T-cells (CD8+), and γδ T-cells (γδTCR+) were evaluated. Both CD62L and CD11b were used as markers of cell activation. Major histocompatibility complex class II was used as a marker of antigen presentation in monocytes. A Milliplex Bovine Cytokine/Chemokine 08-plex kit was used to evaluate plasma concentrations of IFN-γ, IL-1α, IL-1ß, IL-4, IL-6, IL-8, IL-10, and tumor necrosis factor-α. The body weight (BW) change prepartum was calculated as the difference between calving BW and prepartum BW divided by the number of days between measurements. Plasma fatty acids (FA) were measured at -14 and 0 DRP using untargeted gas chromatography with time-of-flight mass spectrometry. Data were analyzed by ANOVA for repeated measures. Cows that developed metritis (n = 57) had greater prepartum BW, prepartum BW loss, and greater FA concentrations at calving. Plasma FA at calving was positively correlated with IL-1ß. Cows that developed metritis had persistent systemic inflammation, which was demonstrated by greater B-cell activation, greater pro-inflammatory cytokine concentrations, and greater cell damage pre- and postpartum. Postpartum, we observed greater polymorphonuclear cell activation and extravasation but lesser monocytes and CD4+ T-cells activation and extravasation, which suggests postpartum immune tolerance. Greater prepartum adiposity in cows that developed metritis may lead to systemic inflammation pre- and postpartum and immune tolerance postpartum, which may lead to failure to prevent bacterial infection, and development of puerperal metritis.


Asunto(s)
Enfermedades de los Bovinos , Enfermedad Inflamatoria Pélvica , Femenino , Bovinos , Animales , Linfocitos T CD8-positivos , Cromatografía de Gases y Espectrometría de Masas/veterinaria , Periodo Posparto , Citocinas , Inflamación/veterinaria , Enfermedad Inflamatoria Pélvica/veterinaria , Lactancia
5.
J Dairy Sci ; 105(6): 5506-5518, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35465991

RESUMEN

Objectives were to evaluate the effect of 2 analogs of PGF2α (cloprostenol vs. dinoprost) and 2 doses (1 injection vs. 2 injections) on luteolysis, follicle diameter, hormonal concentrations, and time to ovulation in dairy heifers. Holstein heifers were fitted with automated estrus detection devices and had their estrous cycle synchronized using PGF2α and an intravaginal insert containing progesterone. Heifers detected in estrus were blocked by weight and randomly assigned to 1 of 4 treatments in a 2 × 2 factorial arrangement: cloprostenol on d 7 after estrus (CLOx1; n = 45), cloprostenol on d 7 and 8 after estrus (CLOx2; n = 41), dinoprost on d 7 after estrus (DINx1; n = 43), or dinoprost on d 7 and 8 after estrus (DINx2; n = 44). Treatment with the first injection of PGF2α was defined as experiment d 0. Area and blood flow of corpus luteum (CL) and diameter of follicles >5 mm were recorded every 12 h from d 0 to estrus and every 6 h thereafter until ovulation. Blood was sampled every 6 h from d 0 until ovulation. Heifers treated with cloprostenol had shorter interval to luteolysis (± SEM; CLOx1 = 23.5 ± 2.2, CLOx2 = 22.9 ± 2.2, DINx1 = 32.6 ± 2.7, DINx2 = 26.4 ± 2.1 h); however, time to ovulation was not affected by treatment. A smaller proportion of heifers treated with a single injection of PGF2α underwent luteolysis compared with heifers treated with 2 injections (CLOx1 = 84.6 ± 6.2, CLOx2 = 100.0 ± 0.0, DINx1 = 59.7 ± 9.8, DINx2 = 96.3 ± 2.7%). Proportion of heifers that ovulated was smaller for DINx1 compared with other treatments (CLOx1 = 88.8 ± 5.1, CLOx2 = 100.0 ± 0.0, DINx1 = 55.2 ± 9.7, DINx2 = 94.4 ± 3.4%). Ovulatory follicle diameter was larger for DINx1 (18.2 ± 2.7 mm) compared with DINx2 (17.4 ± 2.7 mm), whereas dose did not affect the diameter of the ovulatory follicle in heifers treated with cloprostenol (CLOx1 = 17.6 ± 2.7 vs. CLOx2 = 17.8 ± 2.8 mm). Among heifers that underwent luteolysis, progesterone concentrations from 18 to 36 h after treatment were lesser in heifers treated with cloprostenol compared with those treated with dinoprost. Type of PGF2α did not affect progesterone concentrations past 36 h from treatment; however, heifers treated with 2 PGF2α injections had lesser progesterone concentrations and CL blood flow from 36 to 72 h after treatment compared with heifers that received a single PGF2α injection.


Asunto(s)
Dinoprost , Luteólisis , Animales , Bovinos , Cloprostenol/farmacología , Sincronización del Estro , Femenino , Inseminación Artificial/veterinaria , Ovulación , Progesterona
6.
Environ Res ; 202: 111517, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34216609

RESUMEN

Tartrazine degradation was investigated by electrochemical and sonochemical oxidation processes. Anodic oxidation was carried out using boron-doped diamond (BDD) electrodes. The influence of current density and dye initial concentration on the removal of tartrazine from water was analyzed. The experimental results indicate that total removal of tartrazine was obtained, and Chemical Oxygen Demand (COD) and Total Organic Carbon (TOC) removals of up to 94.4% and 72.8% were achieved, respectively. To optimize the process, the pollutant removal percentage, the kinetic rate constant, and the TOC removal efficiency were chosen as target variables. Moreover, sonochemical oxidation experiments at a high-frequency range of cavitation (up to 1 MHz) were performed to establish the influence of three different operating variables, namely ultrasound frequency (0.5-1.1 MHz), ultrasound power (2.0-26.6 W ⋅L-1), and pulse-stop ratio (5:1-1:1). The process was also analyzed in terms of kinetics and energy costs. The kinetics resulted to be three times faster for the electrochemical process. However, the calculated energy costs were very similar, at least at long treatment times. Finally, the influence of three aqueous matrices was investigated. According to the experimental results, the natural occurrence of chloride and/or nitrate ions in water strongly conditions the rate of the process, although at least 90% of tartrazine removal was achieved within the first 50 min of treatment.


Asunto(s)
Tartrazina , Contaminantes Químicos del Agua , Boro , Diamante , Oxidación-Reducción , Agua , Contaminantes Químicos del Agua/análisis
7.
J Eur Acad Dermatol Venereol ; 35 Suppl 2: 3-11, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34668238

RESUMEN

INTRODUCTION: Hair disorders are one of the most common conditions within dermatology practice but, although new diagnostic tools and therapeutic options have arisen, the management of these patients still represents a major clinical challenge. OBJECTIVE: This study aimed at gathering information and achieving consensus on relevant recommendations on the latest advances in alopecia, trichoscopy and hair dermocosmetics. METHODS: Experts of the steering committee consulted the available evidence on trichology-related areas from the past 5 years and formulated recommendations based on the evidence and their experience. A modified two-round Delphi procedure was performed among 45 European dermatologists experts in trichology to consult their degree of agreement on twenty recommendations, using a 4-point Likert scale. Consensus was defined as >80% of participants scoring either 1 (totally agree) or 2 (agree). RESULTS: In the first round of the Delphi questionnaire, 75% of the recommendations reached consensus. Those that were not agreed upon were reformulated by the steering committee and voted again after an online meeting, where consensus was achieved in all recommendations. CONCLUSIONS: All recommendations reached consensus after the two-round Delphi questionnaire and may be useful in clinical practice for dermatologists. The participants agreed that besides this consensus, further clinical studies are needed to assess the benefits of the emerging tools and treatments and to clarify the controversies that still exist in the field, aiming at improving patients' quality of life.


Asunto(s)
Calidad de Vida , Consenso , Técnica Delphi , Humanos , Encuestas y Cuestionarios
8.
Nanotechnology ; 31(40): 405204, 2020 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-32544891

RESUMEN

The zero-bias microwave detection capability of self-switching diodes (SSDs) based on AlGaN/GaN is analyzed in a wide temperature range, from 10 K to 300 K. The measured responsivity shows an anomalous enhancement at low temperature, while the detected voltage exhibits a roll-off in frequency, which can be attributed to the presence of surface and bulk traps. To gain a deep insight into this behavior, a systematic DC and AC characterization of the diodes has been carried out in the mentioned temperature range. DC results confirm the existence of traps and AC measurements allow us to identify their properties. In particular, impedance studies enable to distinguish two types of traps: at the lateral surfaces of the channel, with a wide spread of relaxation times, and in the bulk.

9.
J Environ Manage ; 256: 109972, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-31989988

RESUMEN

The degradation of a model pollutant, tartrazine, very used in food industry and usually present in WWTPs effluents and surface waters, was investigated by nine activated homogeneous catalytic processes, namely, Fe3+/H2O2, Fe2+/H2O2, UV/H2O2, UV/S2O82-, UV/Fe2+/H2O2, UV/Fe3+/H2O2, UV, VIS/Fe3+/H2O2, and VIS/Fe3+/H2O2/C2O42-. In order to compare the mineralization and oxidation ability of each process, the removal of dye, chemical oxygen demand (COD) and total organic carbon (TOC) were analyzed, as well as the overall kinetic rate constant. Also, the different oxidation path-ways (direct photolysis and/or oxidation by free radicals) were estimated for each system. After the comparison, the Fenton process, which had the highest mineralization values, was tested in luminous and dark phases using designed experiments, and the influences of all operating variables were studied by RSM.


Asunto(s)
Peróxido de Hidrógeno , Contaminantes Químicos del Agua , Catálisis , Cinética , Oxidación-Reducción , Fotólisis , Rayos Ultravioleta
11.
Eur J Vasc Endovasc Surg ; 51(4): 536-42, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26916389

RESUMEN

OBJECTIVES: The use of branched stent grafts for the treatment of thoracoabdominal aneurysms [TAAA] is increasing, but mating stent graft choice has not been studied. This study combined experience of five high volume centres to assess a preferred mating stent. METHODS: Data from five centres were retrospectively combined. Patients were included if they underwent stent graft for treatment of TAAA that used only branches to mate with visceral and renal vessels. All patients with fenestrations in their device were excluded. Perioperative details, reintervention, occlusion, and death were recorded. Outcome of occlusion or reintervention, as well as a composite outcome of any death, occlusion, or reintervention was planned using a per-patient, and per-branch analysis. RESULTS: In 235 included patients, there were 940 vessels available for placement of mating stent. The average age of included patients was 70 years (SD 7.9), and 179 of the 235 were male. Medical comorbidities included diabetes in 29/234 (12.4%), current smoker in 81/233 (34.8%), and COPD in 77/234 (32.9%). The primary stent deployed was self-expanding in 556 branches, balloon expandable in 231 branches, and was unknown in 92 branches. After a mean of 20.7 months (SD 25) follow-up, there have been 44 incidents of occlusion or reintervention, of which 40 culprit stents are known. Where the stent placed is known, the event rate in renal branches (35/437, 8%) is higher than that of visceral branches (8/443, 1.8%). There is no difference in occlusion or reintervention between self-expanding and balloon expandable stents (HR 0.95, p = .91) but there is a statistically significant difference between renal and visceral artery occlusions (HR 3.51, p = 0.001). CONCLUSION: There appears to be no difference in occlusion or reintervention rate for branch vessels mated with balloon expandable compared with self-expanding stents. Renal events appear to outnumber visceral events in this population.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares/instrumentación , Stents , Anciano , Aneurisma de la Aorta Torácica/diagnóstico , Aneurisma de la Aorta Torácica/mortalidad , Aneurisma de la Aorta Torácica/fisiopatología , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/mortalidad , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/mortalidad , Europa (Continente) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Grado de Desobstrucción Vascular
12.
Eur J Vasc Endovasc Surg ; 52(2): 141-8, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27105550

RESUMEN

OBJECTIVE/BACKGROUND: The objective was to investigate renal outcomes following endovascular repair of thoraco-abdominal aortic aneurysms (TAAA) comparing fenestrations with branches for the renal arteries. METHODS: Renal outcomes following TAAA endovascular repair performed with renal branches were collected from five high volume European centers and compared with renal outcomes following TAAA endovascular repair performed with renal fenestrations at one center. Renal re-intervention and occlusion rates, and freedom from any renal outcome and death were analyzed by patient and target vessel. Estimated glomerular filtration rate (eGFR) was calculated and collected pre-operatively and at the last available follow up. RESULTS: In total, 449 patients were included in this retrospective study (235 treated with branched devices [BEVAR] and 214 with fenestrated devices [FEVAR]). Altogether, 856 renal vessels were analyzed (445 perfused by branches and 411 by fenestrations). Both groups were comparable except for sex and smoking habits. Technical success rates were 95% and 99%, respectively. Mean ± SD follow up was 19 ± 18 months after BEVAR and 24 ± 20 months after FEVAR. During follow up, renal re-intervention rates were similar in both groups (4.7% vs. 5.2%). The renal occlusion rate was significantly higher following BEVAR (9.6% vs. 2.3%; p < .01), and the 2 year freedom for renal occlusion rate was 90.4% (SE 85.8-95.3%) following BEVAR and 97.1% (SE 94.6-99.7%) following FEVAR (p < .01). During follow up, a 12% median decrease in eGFR was observed following BEVAR versus 9% following FEVAR (non-significant). The 2 year survival rates were 73.4% (SE 66.6-80.9%) and 81.8% (SE 76.1-87.9%) following BEVAR and FEVAR, respectively. CONCLUSION: Mid-term renal outcomes following endovascular repair of TAAA are satisfactory. Endograft designs incorporating renal fenestrations rather than renal branches are associated with significantly lower occlusion rates. A prospective trial is now required to confirm these results.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Riñón/fisiopatología , Arteria Renal/cirugía , Anciano , Angioplastia/métodos , Aneurisma de la Aorta Torácica/complicaciones , Aneurisma de la Aorta Torácica/fisiopatología , Prótesis Vascular , Femenino , Tasa de Filtración Glomerular , Humanos , Riñón/irrigación sanguínea , Masculino , Obstrucción de la Arteria Renal/etiología , Estudios Retrospectivos , Stents , Resultado del Tratamiento , Injerto Vascular/métodos
13.
Phys Chem Chem Phys ; 18(18): 12755-67, 2016 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-27097793

RESUMEN

Cis and trans proline conformers are often associated with dramatic changes in the biological function of peptides. A slow equilibrium between cis and trans Ile-Pro amide bond conformers occurs in constrained derivatives of the native marine cyclic heptapeptide stylostatin 1 (cyclo-(NSLAIPF)), a potential anticancer agent. In this work, four cyclopeptides, cyclo-(NSTAIPF), cyclo-(KSTAIPF), cyclo-(RSTAIPF) and cyclo-(DSTAIPF), which are structurally related to stylostatin 1, are experimentally and computationally examined in order to assess the effect of residue mutations on the cis-trans conformational ratio and the apparent capacity to form dimeric aggregates. Primarily, cyclo-(KSTAIPF) and cyclo-(RSTAIPF) showed specific trends in circular dichroism, MALDI-TOF and HPLC purification experiments, which suggests the occurrence of peptide dimerization. Meanwhile, the NMR spectrum of cyclo-(KSTAIPF) indicates that this cyclopeptide exists in the two slow-exchange families of conformations mentioned above. Molecular dynamics simulations combined with quantum mechanical calculations have shed light on the factors governing the cis/trans conformational ratio. In particular, we have found that residue mutations affect the internal hydrogen bond pattern which ultimately tunes the cis/trans conformational ratio and that only trans conformers are capable of aggregating due to the shape complementarity of the two subunits.


Asunto(s)
Péptidos Cíclicos/química , Prolina/química , Dimerización , Isomerismo , Espectroscopía de Resonancia Magnética , Simulación de Dinámica Molecular , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
15.
Eur J Vasc Endovasc Surg ; 49(3): 248-54, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25575833

RESUMEN

OBJECTIVE/BACKGROUND: Spinal cord ischemia (SCI) is a devastating complication following endovascular thoracoabdominal aortic aneurysm (TAAA) repair. In an attempt to reduce its incidence two peri-procedural changes were implemented by the authors in January 2010: (i) all large sheaths are withdrawn from the iliac arteries immediately after deploying the central device and before cannulation and branch extension to the visceral vessels; (ii) the peri-operative protocol has been modified in an attempt to optimize oxygen delivery to the sensitive cells of the cord (aggressive blood and platelet transfusion, median arterial pressure monitoring >85 mmHg, and systematic cerebrospinal fluid drainage). METHODS: Between October 2004 and December 2013, 204 endovascular TAAA repairs were performed using custom made devices manufactured with branches and fenestrations to maintain visceral vessel perfusion. Data from all of these procedures were prospectively collected in an electronic database. Early post-operative results in patients treated before (group 1, n = 43) and after (group 2, n = 161 patients) implementation of the modified implantation and peri-operative protocols were compared. RESULTS: Patients in groups 1 and 2 had similar comorbidities (median age at repair 70.9 years [range 65.2-77.0 years]), aneurysm characteristics (median diameter 58.5 mm [range 53-65 mm]), and length of procedure (median 190 minutes [range 150-240 minutes]). The 30 day mortality rate was 11.6% in group 1 versus 5.6% in group 2 (p = .09). The SCI rate was 14.0% versus 1.2% (p < .01). If type IV TAAAs were excluded from this analysis, the SCI rate was 25.0% (6/24 patients) in group 1 versus 2.1% (2/95 patients) in group 2 (p < .01). CONCLUSION: The early restoration of arterial flow to the pelvis and lower limbs, and aggressive peri-operative management significantly reduces SCI following type I-III TAAA endovascular repair. With the use of these modified protocols, extensive TAAA endovascular repairs are associated with low rates of SCI.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/métodos , Procedimientos Endovasculares/métodos , Extremidad Inferior/irrigación sanguínea , Pelvis/irrigación sanguínea , Isquemia de la Médula Espinal/prevención & control , Anciano , Aneurisma de la Aorta Torácica/diagnóstico , Aneurisma de la Aorta Torácica/mortalidad , Aneurisma de la Aorta Torácica/fisiopatología , Prótesis Vascular , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/instrumentación , Comorbilidad , Bases de Datos Factuales , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/instrumentación , Procedimientos Endovasculares/mortalidad , Femenino , Francia/epidemiología , Hospitales de Alto Volumen , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Flujo Sanguíneo Regional , Medición de Riesgo , Factores de Riesgo , Isquemia de la Médula Espinal/diagnóstico , Isquemia de la Médula Espinal/mortalidad , Isquemia de la Médula Espinal/fisiopatología , Stents , Factores de Tiempo , Resultado del Tratamiento
16.
Eur J Vasc Endovasc Surg ; 50(4): 420-30, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26021528

RESUMEN

OBJECTIVE: The purpose of this study was to analyze immediate and long-term renal outcomes (renal function and renal events) after fenestrated (FEVAR) and branched endovascular aortic aneurysm repair (BEVAR). METHODS: All FEVAR and BEVAR performed between October 2004 and October 2012 were included in this study. Post-operative acute renal failure (ARF) was defined according to the RIFLE criteria. Renal volume (calculated with a 3D workstation) and estimated glomerular filtration rate (GFR) (estimated with the Modification of Diet in Renal Disease [MDRD] formula) were evaluated before the procedure, before discharge, 12 months after, and yearly thereafter. Renal stent occlusion, dissection, fracture, stenosis, kink, renal stent related endoleak, and renal stent secondary intervention were all considered "renal composite events" and analyzed. A time to event analysis was performed for renal events and secondary renal interventions. RESULTS: 225 patients were treated with FEVAR and BEVAR. Renal target vessels (n = 427) were perfused by fenestrations (n = 374), or branches (n = 53). Median follow up was 3.1 years (2.9-3.3 years). Technical success was achieved in 95.5% of patients. Post-operative ARF was seen in 64 patients (29%). Mean total renal volume and eGFR at 1 year, 2 year, and 3 year follow up were significantly lower when compared with pre-operative levels (after BEVAR and FEVAR); the decrease at 3 years was 14.8% (6.7%; 22.2%) (p = .0006) for total renal volume and 14.3% (3.1%; 24.3%) (p = .02) for eGFR. The 30 day and 5 year freedom from renal composite event was 98.6% (95.8-99.6%) and 84.5% (76.5-89.9%) after FEVAR and BEVAR (NS). The 30 day and 5 year freedom from renal occlusion was 99.5% (96.7-99.9%) and 94.4% (89.3-97.1%) after FEVAR and BEVAR (NS). CONCLUSION: FEVAR and BEVAR are durable options for the treatment of complex aortic aneurysms and are associated with low renal morbidity, without differences between devices types. The clinical impact of decreasing renal volume over time in these patients is yet to be fully understood.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular , Prótesis Vascular , Procedimientos Endovasculares , Enfermedades Renales/etiología , Stents , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Torácica/diagnóstico , Aneurisma de la Aorta Torácica/mortalidad , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/instrumentación , Implantación de Prótesis Vascular/mortalidad , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/instrumentación , Procedimientos Endovasculares/mortalidad , Femenino , Tasa de Filtración Glomerular , Humanos , Riñón/fisiopatología , Enfermedades Renales/diagnóstico , Enfermedades Renales/mortalidad , Enfermedades Renales/fisiopatología , Enfermedades Renales/terapia , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
17.
Eur J Vasc Endovasc Surg ; 49(5): 541-8, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25752417

RESUMEN

OBJECTIVES: This study evaluated a new strategy to assess technical success after standard and complex endovascular aortic repair (EVAR), combining completion contrast enhanced cone beam computed tomography (ceCBCT) and post-operative contrast enhanced ultrasound (CEUS). METHODS: Patients treated with bifurcated or fenestrated and branched endografts in the hybrid room during the study period were included. From December 2012 to July 2013, a completion angiogram (CA) was performed at the end of the procedure, and computed tomography angiography (CTA) before discharge (group 1). From October 2013 to April 2014, a completion ceCBCT was performed, followed by CEUS during the 30 day post-operative period (group 2). The rate of peri-operative events (type I or III endoleaks, kinks, occlusion of target vessels), need for additional procedures or early secondary procedures, total radiation exposure (mSv), and total volume of contrast medium injected were compared. RESULTS: Seventy-nine patients were included in group 1 and 54 in group 2. Peri-operative event rates were respectively 8.9% (n = 7) and 33.3% (n = 18) (p = .001). Additional procedures were performed in seven patients (8.9%) in group 1 versus 17 (31.5%) in group 2 (p = .001). Two early secondary procedures were performed in group 2 (3.7%), and three (3.8%) in group 1 (p = .978). Median radiation exposure due to CBCT was 7 Gy cm(2) (5.25-8) (36%, 27%, and 9% of the total procedure exposure, respectively for bifurcated, fenestrated, and branched endografts). CEUS did not diagnose endoleaks or any adverse events not diagnosed by ceCBCT. Overall radiation and volume of contrast injected during the patient hospital stay in groups 1 and 2 were 34 (25.8-47.3) and 11 (5-20.5) mSv, and 184 (150-240) and 91 (70-132.8) mL respectively (reduction of 68% and 50%, p < .001). CONCLUSIONS: Completion ceCBCT is achievable in routine practice to assess technical success after EVAR. Strategies to evaluate technical success combining ceCBCT and CEUS can reduce total in hospital radiation exposure and contrast medium volume injection.


Asunto(s)
Angiografía , Aneurisma de la Aorta Abdominal/cirugía , Procedimientos Endovasculares , Procedimientos Quirúrgicos Vasculares , Anciano , Angiografía/métodos , Implantación de Prótesis Vascular/métodos , Medios de Contraste/uso terapéutico , Endofuga/diagnóstico por imagen , Endofuga/cirugía , Femenino , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía
18.
Appl Microbiol Biotechnol ; 99(12): 5109-21, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25874532

RESUMEN

Magnetotactic bacteria are a diverse group of prokaryotes that share the unique ability of biomineralizing magnetosomes, which are intracellular, membrane-bounded crystals of either magnetite (Fe3O4) or greigite (Fe3S4). Magnetosome biomineralization is mediated by a number of specific proteins, many of which are localized in the magnetosome membrane, and thus is under strict genetic control. Several studies have partially elucidated the effects of a number of these magnetosome-associated proteins in the control of the size of magnetosome magnetite crystals. However, the effect of MamC, one of the most abundant proteins in the magnetosome membrane, remains unclear. In this present study, magnetite nanoparticles were synthesized inorganically in free-drift experiments at 25 °C in the presence of different concentrations of the iron-binding recombinant proteins MamC and MamCnts (MamC without its first transmembrane segment) from the marine, magnetotactic bacterium Magnetococcus marinus strain MC-1 and three commercial proteins [α-lactalbumin (α-Lac), myoglobin (Myo), and lysozyme (Lyz)]. While no effect was observed on the size of magnetite crystals formed in the presence of the commercial proteins, biomimetic synthesis in the presence of MamC and MamCnts at concentrations of 10-60 µg/mL resulted in the production of larger and more well-developed magnetite crystals (~30-40 nm) compared to those of the control (~20-30 nm; magnetite crystals grown protein-free). Our results demonstrate that MamC plays an important role in the control of the size of magnetite crystals and could be utilized in biomimetic synthesis of magnetite nanocrystals.


Asunto(s)
Alphaproteobacteria/metabolismo , Proteínas Bacterianas/metabolismo , Óxido Ferrosoférrico/metabolismo , Alphaproteobacteria/química , Alphaproteobacteria/genética , Proteínas Bacterianas/genética , Óxido Ferrosoférrico/química , Magnetosomas/química , Magnetosomas/genética , Magnetosomas/metabolismo , Tamaño de la Partícula
19.
Radiologia ; 57(2): 101-12, 2015.
Artículo en Inglés, Español | MEDLINE | ID: mdl-25554118

RESUMEN

Bile duct tumors are benign or malignant lesions which may be associated to risk factors or potentially malignant lesions. They constitute an heterogenous entities group with a different biological behavior and prognosis according to location and growth pattern. We revise the role of the radiologist in order to detect, characterize and stage these tumors, specially the importance of their classification when deciding an appropriate management and treatment.


Asunto(s)
Neoplasias de los Conductos Biliares/diagnóstico por imagen , Colangiocarcinoma/diagnóstico por imagen , Humanos , Lesiones Precancerosas/diagnóstico por imagen
20.
Anal Chem ; 86(22): 11028-32, 2014 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-25312744

RESUMEN

The design and evaluation of analytical methods that permit quantitative analysis of specific DNA sequences is exponentially increasing. For this purpose, highly sensitive methodologies usually based on labeling protocols with fluorescent dyes or nanoparticles are often explored. Here, the possibility of label-free signal amplification using end-point polymerase chain reaction (PCR) are exploited using on-column agarose gel electrophoresis as separation and inductively coupled plasma-mass spectrometry (ICP-MS) for the detection of phosphorus in amplified DNA sequences. The calibration of the separation system with a DNA ladder permits direct estimation of the size of the amplified gene fragment after PCR. With this knowledge, and considering the compound-independent quantification capabilities exhibited by ICP-MS for phosphorus (it is only dependent on the number of P atoms per molecule), the correlation of the P-peak area of the amplified gene fragment, with respect to the gene copy numbers (in the starting DNA), is then established. Such a relationship would permit the determination of copy number variations (CNVs) in genomic DNA using ICP-MS measurements. The method detection limit, in terms of the required amount of starting DNA, is ∼6 ng (or 1000 cells if 100% extraction efficiency is expected). The suitability of the proposed label-free amplification strategy is applied to CNVs monitoring in cells exposed to a chemical agent capable of deletion induction, such as cisplatin.


Asunto(s)
Variaciones en el Número de Copia de ADN , ADN/genética , Internet , Reacción en Cadena de la Polimerasa , Secuencia de Bases , Línea Celular , Electroforesis , Humanos , Espectrometría de Masas , Reacción en Cadena de la Polimerasa/instrumentación
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