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1.
J Dairy Sci ; 107(7): 4394-4408, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38278300

RESUMO

Our objectives were to determine the effects of reducing dietary CP concentration on nutrient digestibility, rumen function, N balance, and serum AA concentration for dairy cows in late lactation. At the initiation of the experimental period, we stratified Holstein cows (n = 128; mean ± SD 224 ± 54 DIM) by parity and days pregnant (86 ± 25 d) and assigned them to 1 of 16 pens. For 3 wk, all cows received a covariate diet containing 16.9% CP (DM basis). For the subsequent 12 wk, we assigned pens to 1 of 4 treatments containing 16.2%, 14.4%, 13.4%, or 11.9% CP (DM basis) in a randomized complete block design. Diets were fed as a TMR once daily. To reduce dietary CP, we replaced soybean meal with soybean hulls in the concentrate mix (DM basis). Diet evaluations suggested that several EAA, especially His, limited productivity as dietary CP declined. Digestibility of DM and CP decreased linearly with dietary CP reduction. Digestibility of NDF and potentially digestible NDF tended to respond in a quadratic pattern with the greatest digestibility at intermediate treatments. The reduction in dietary CP did not affect ruminal pH, but ruminal ammonia-N and branched-chain VFA concentrations declined linearly. The concentration of milk urea-N and plasma urea-N, secretion of milk N, and excretions of fecal N, urinary N, urinary urea-N, and unaccounted N decreased linearly with the reduction in dietary CP concentration. Urinary N expressed as a percentage of N intake was unaffected by dietary CP. Serum concentrations of total essential AA and NEAA were unaffected by dietary CP concentration. However, the ratio of essential to NEAA decreased with decreasing dietary CP. Serum 3-methylhistidine concentration increased linearly with decreasing dietary CP concentration, indicating greater skeletal muscle breakdown. Although our trial confirmed that reducing dietary CP decreased absolute excretion of urinary N, diet evaluations suggested that milk protein production decreased as certain essential AA became increasingly limited. Thus, reduced-CP diets have the potential to lessen reactive-N outputs of late-lactation cows, but more research is needed to design diets that minimize deleterious effects on productivity.


Assuntos
Ração Animal , Dieta , Proteínas Alimentares , Digestão , Lactação , Nitrogênio , Animais , Bovinos/metabolismo , Feminino , Nitrogênio/metabolismo , Nitrogênio/urina , Dieta/veterinária , Proteínas Alimentares/metabolismo , Rúmen/metabolismo , Leite/metabolismo , Leite/química
2.
Neurologia (Engl Ed) ; 39(3): 226-234, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37442428

RESUMO

INTRODUCTION: Cerebral venous thrombosis (CVT) is an uncommon cause of stroke that mainly affects young adults. Early, accurate diagnosis can reduce the rate and severity of complications. OBJECTIVE: The aim of this study was to analyse the clinical characteristics, management, and treatment of CVT in different centres in Spain. METHODS: We conducted a multicentre, retrospective, descriptive study of patients hospitalised due to CVT between 2008 and 2017 at 10 Spanish centres. RESULTS: We included 256 patients, with a mean age (SD) of 49.8 (18.7) years; 51% of patients were women. The most frequent symptoms were headache (73%), focal deficits (50%), epileptic seizures (33%), and encephalopathy (21%). The most frequent localisations were the superior sagittal sinus (12.5%), the transverse sinus (10.9%), and 2 or more sinuses or veins (66.4%). Thrombophilia was the most frequent known aetiology (24%), and was most commonly associated with the prothrombin G20210A mutation (19%). Forty-six percent of patients were treated with antithrombotics for 3 to 6 months, 21% for one year, and 22.6% required indefinite anticoagulation. Endovascular therapy was performed in 5% of cases, and 33% required neurosurgery. Regarding outcomes, 75% of patients were independent at 3 months (modified Rankin Scale [mRS] score ≤ 2), with papilloedema (P =  .03), focal deficits (P = .001), and encephalopathy (P < .001) showing a statistically significant association with poor prognosis (mRS > 3). The in-hospital mortality rate was 4.3%, with a 3-month mortality rate of 6.3%. CONCLUSION: The diverse risk factors and variable presentation of CVT represent a challenge in the diagnosis and treatment of this condition. To improve prognosis and reduce mortality, it is essential to establish management protocols for this entity.


Assuntos
Trombose Intracraniana , Acidente Vascular Cerebral , Trombose Venosa , Adulto Jovem , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Estudos Retrospectivos , Espanha , Trombose Venosa/terapia , Trombose Venosa/tratamento farmacológico , Trombose Intracraniana/terapia , Trombose Intracraniana/tratamento farmacológico
3.
J Chem Phys ; 158(17)2023 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-37139999

RESUMO

The non-exponential character of the structural relaxation is considered one of the hallmarks of the glassy dynamics, and in this context, the relatively narrow shape observed by dielectric techniques for polar glass formers has attracted the attention of the community for long time. This work addresses the phenomenology and role of specific non-covalent interactions in the structural relaxation of glass-forming liquids by the study of polar tributyl phosphate. We show that dipole interactions can couple to shear stress and modify the flow behavior, preventing the occurrence of the simple liquid behavior. We discuss our findings in the general framework of glassy dynamics and the role of intermolecular interactions.

4.
Int J Surg ; 96: 106169, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34848373

RESUMO

BACKGROUND: Controlled donation after circulatory death (cDCD) has expanded the donor pool for liver transplantation (LT). However, transfusion requirements and perioperative outcomes should be elucidated. The aim of this multicenter study was to assess red blood cell (RBC) transfusions, one-year graft and patient survival after LT after cDCD with normothermic regional perfusion (NRP) compared with donors after brain death (DBD). METHODS: 591 LT carried out in ten centers during 2019 were reviewed. Thromboelastometry was used to manage coagulation and blood product transfusion in all centers. Normothermic regional perfusion was the standard technique for organ recovery. RESULTS: 447 patients received DBD and 144 cDCD with NRP. Baseline MCF Extem was lower in the cDCD group There were no differences in the percentage of patients (63% vs. 61% p = 0.69), nor in the number of RBC units transfused (4.7 (0.2) vs 5.5 (0.4) in DBD vs cDCD, p = 0.11. Twenty-six patients (6%) died during admission for LT in the DBD group compared with 3 patients (2%) in the cDCD group (p = 0.15). To overcome the bias due to a worse coagulation profile in cDCD recipients, matched samples were compared. No differences in baseline laboratory data, or in intraoperative use of RBC or one-year outcome data were observed between DBD and cDCD recipients. CONCLUSIONS: cDCD with NRP is not associated with increased RBC transfusion. No differences in graft and patient survival between cDCD and DBD were found. Donors after controlled circulatory death with NRP can increasingly be utilized with safety, improving the imbalance between organ donors and the ever-growing demand.


Assuntos
Morte Encefálica , Transplante de Fígado , Estudos de Coortes , Sobrevivência de Enxerto , Humanos , Preservação de Órgãos , Perfusão , Doadores de Tecidos
5.
Neurologia (Engl Ed) ; 2021 Sep 09.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34511275

RESUMO

INTRODUCTION: Cerebral venous thrombosis (CVT) is an uncommon cause of stroke that mainly affects young adults. Early, accurate diagnosis can reduce the rate and severity of complications. OBJECTIVE: The aim of this study was to analyse the clinical characteristics, management, and treatment of CVT in different centres in Spain. METHODS: We conducted a multicentre, retrospective, descriptive study of patients hospitalised due to CVT between 2008 and 2017 at 11 Spanish centres. RESULTS: We included 256 patients, with a mean age (SD) of 49.8 (18.7) years; 51% of patients were women. The most frequent symptoms were headache (73%), focal deficits (50%), epileptic seizures (33%), and encephalopathy (21%). The most frequent localisations were the superior sagittal sinus (12.5%), the transverse sinus (10.9%), and 2 or more sinuses or veins (66.4%). Thrombophilia was the most frequent known aetiology (24%), and was most commonly associated with the prothrombin G20210A mutation (19%). Forty-six percent of patients were treated with antithrombotics for 3-6 months, 21% for one year, and 22.6% required indefinite anticoagulation. Endovascular therapy was performed in 5% of cases, and 33% required neurosurgery. Regarding outcomes, 75% of patients were independent at 3 months (modified Rankin Scale [mRS] score ≤ 2), with papilloedema (P=.03), focal deficits (P=.001), and encephalopathy (P <.001) showing a statistically significant association with poor prognosis (mRS> 3). The in-hospital mortality rate was 4.3%, with a 3-month mortality rate of 6.3%. CONCLUSION: The diverse risk factors and variable presentation of CVT represent a challenge in the diagnosis and treatment of this condition. To improve prognosis and reduce mortality, it is essential to establish management protocols for this entity.

6.
J Dairy Sci ; 102(9): 8546-8558, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31301834

RESUMO

In the semi-arid highlands of central Mexico, triticale (× Triticosecale L.) is emerging as an alternative, less water-demanding forage crop than alfalfa for dairy cattle. Studies reported here were aimed at evaluating triticale hay (TH) relative to alfalfa hay (AH) for lactating cow performance, apparent digestibility, N partition, and ruminal degradation kinetics of dry matter (DM), crude protein (CP), and neutral detergent fiber (NDF). Study 1 was conducted on a privately owned farm. Four barns were used to conduct 4 replicated 3 × 3 Latin squares (1 barn = 1 square), where each barn included 3 pens (experimental units) receiving 1 of 3 dietary treatments. Each pen had 62 Holstein dairy cows. All diets included a forage-to-concentrate ratio of 42:58 (DM basis), which is typical for intensive dairy farms of the region. Dietary treatments were formulated to replace AH with TH on a CP basis, and included (DM basis) 15.1% AH and 0% TH, 9.0% AH and 7.4% TH, and 0% AH and 16.4% TH. Diets were iso-energetic (1.64 Mcal of net energy for lactation/kg of DM) and iso-nitrogenous (17.9% CP). Pen-level DM intake and milk production were from all cows in the pen, but pen-level milk composition, apparent digestibility, and N partitioning were from 8 cows (observational units) randomly selected in each pen. Orthogonal contrasts were used to determine linear and quadratic effects of increasing TH from 0 to 7.4, and 16.4% of dietary DM. Although DM intake was not affected, there was a tendency for CP intake to decline linearly and for NDF intake to increased linearly as TH replaced AH in the diet. Milk production declined linearly by 0.077 kg/d for each additional percentage unit of TH in the diet, which amounted to a 3.5% decline when TH replaced AH entirely. However, no effect was observed on energy-corrected milk production because of a compensatory linear effect of increasing milk fat concentration with the incorporation of TH in the diet. Total-tract NDF digestibility tended to increase linearly by 18.5%, but no differences were detected for urinary urea-N excretion and for N utilization estimated as milk N/(fecal N + urinary N + milk N). Study 2 was an in situ trial conducted to determine the degradation kinetics of AH and TH used in study 1. In spite of differences in degradation kinetics parameters for DM, CP, and NDF, only NDF effective ruminal degradation tended to be greater for TH than AH. Replacing AH with TH at the level typically found in intensive dairy farms of the semi-arid regions of Mexico had minimal effects on milk production and N utilization.


Assuntos
Bovinos/fisiologia , Lactação/fisiologia , Medicago sativa , Nitrogênio/metabolismo , Triticale , Ração Animal , Animais , Clima , Indústria de Laticínios/métodos , Dieta/veterinária , Fibras na Dieta/administração & dosagem , Digestão , Feminino , Medicago sativa/metabolismo , México , Leite/química , Zea mays/metabolismo
7.
J Dairy Sci ; 102(2): 1601-1607, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30471912

RESUMO

Our objectives were to assess the relationships between milk urea N (MUN), serum urea N (SUN), urine N (UN), and urinary urea N (UUN) in late-lactation cows fed N-limiting diets and compare these relationships with those previously established. Data were from a pen-based study in which 128 Holstein cows had been assigned to 1 of 16 pens in a randomized complete block design to assess the effects of diets containing 16.2, 14.4, 13.1, and 11.8% crude protein (CP, dry matter basis) during a 12-wk period. At least half of the cows in each pen were randomly selected to collect pen-level samples of serum and urine in wk 3, 7, and 11, when wk in lactation averaged 35, 39, and 43, respectively. A mixed model was developed to study the relationship of MUN with SUN, UN, and UUN. Week of lactation did not affect the relation between MUN and SUN across dietary treatments. However, we found a week × MUN interaction, suggesting that between wk 35 and 43 of lactation, UN excretion decreased from 89 to 73 g/d (-17 g/d) when MUN was 6.0 mg/dL (11.8% dietary CP) but increased from 142 to 149 g/d (+7 g/d) when MUN was 13.3 mg/dL (16.2% dietary CP). These effects were essentially due to changes in UUN excretion, which declined from 54 to 37 g/d (-17 g/d) and increased from 112 to 117 g/d (+5 g/d) when MUN was 6.0 and 13.3 mg/dL, respectively. When MUN was 11.2 mg/dL (15% dietary CP), UN and UUN excretions remained constant over time. Based on root mean squared prediction error and the concordance correlation coefficient, these data did not conform to most previously published prediction equations because of both mean and slope biases. The discrepancy could have resulted from difference in study design (cow vs. pen as experimental unit), dietary treatments (energy vs. N-limiting diets), frequency of measurement and duration of adaptation period (single measurement after 1 to 3 wk of adaptation vs. repeated measurements over a 12-wk period), method for determining urine volume (total collection vs. spot sampling), and the assay used to measure MUN. However, our data captured changes in kidney physiology that warrant further studies of long-term renal adaptation to N-limiting diets.


Assuntos
Bovinos/metabolismo , Dieta/veterinária , Leite/química , Nitrogênio/metabolismo , Animais , Nitrogênio da Ureia Sanguínea , Bovinos/urina , Feminino , Lactação , Nitrogênio/urina , Ureia/análise , Ureia/urina
8.
Transplant Proc ; 50(8): 2317-2319, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30316349

RESUMO

Transplant Procurement Management and the University of Barcelona has offered a Master of Donation and Transplantation degree since 2004. The aim of this study is to analyze the number of participants, their profiles, and scores to evaluate improving measures introduced since 2011, when the modular structure was stablished. The data is organized in 3 groups: number of participants, profile, and scores in each module. The variables for the profile are gender, nationality, and background. According to the number of participants, 127 professionals were trained since 2011, with a decrease in the last classes (21; 20; 15). Regarding their profiles, from 2011 until 2016 the proportion of women was higher (63.13%). The background heterogeneity was an average of 4 different backgrounds in each edition, and medicine was most frequent background for students (58.27%). Participants were from 37 countries, mostly from the United States (45.6%) and Europe (40.9%). As for the scores, participants were evaluated in 4 modules (Donation, Transplantation, Management, and Tissue Banking), an internship, and a final master dissertation. The Donation module presented the lowest score (7.45/10) and the Transplantation module the highest (8.22/10). Considering that the main characteristics of the master's degree are the participants' internationality and heterogeneity, improvement measures must continue focusing on flexibility in the module selection and promoting the online modality.


Assuntos
Educação Profissionalizante/métodos , Obtenção de Tecidos e Órgãos , Europa (Continente) , Feminino , Humanos , Masculino , Estudantes
9.
Phys Chem Chem Phys ; 20(44): 27758-27765, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30209466

RESUMO

The impact of supramolecular aggregate formation on the shear viscosity response of hydrogen bonded liquids was investigated. In particular, we study the shear mechanical response of several monoalcohols showing exponential and non-exponential shape dielectric Debye-like relaxation. In addition to the structural relaxation, distinctive of the glass transition, and the terminal crossover to pure viscous flow, characteristic of simple liquid flow, systematic analysis of complex viscosity curves evidences the presence of an additional intermediate process between those two. While the recovery of pure viscous flow would reflect the complete relaxation of the hydrogen bonded aggregates the intermediate process correlates with the rotational dynamics of hydroxyl groups, potentially caused by the breaking of individual hydrogen bonds.

10.
Rev Neurol ; 66(9): 322-323, 2018 May 01.
Artigo em Espanhol | MEDLINE | ID: mdl-29696621
11.
Am J Transplant ; 18(1): 197-206, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28649744

RESUMO

Mannose-binding lectin (MBL) is synthesized by the liver and binds to microbes. MBL2 gene polymorphisms produce intermediate/low/null or normal MBL serum levels (MBL-deficient or MBL-sufficient phenotypes, respectively). We aimed to evaluate the incidence and severity of infection, rejection, and survival within 1 year after liver transplantation (LT) according to donor and recipient MBL2 gene polymorphisms. A repeated-event analysis for infection episodes (negative binomial regression, Andersen-Gill model) was performed in 240 LTs. Four hundred twenty-eight infectious episodes (310 bacterial, 15 fungal, 65 cytomegalovirus [CMV]-related, and 38 viral non-CMV-related episodes) and 48 rejection episodes were recorded. The main bacterial infections were urinary (n = 82, 26%) and pneumonia (n = 69, 22%). LT recipients of MBL-deficient livers had a higher risk of bacterial infection (incidence rate ratio [IRR] 1.48 [95% confidence interval 1.04-2.09], p = 0.028), pneumonia (IRR 2.4 [95% confidence interval 1.33-4.33], p = 0.013), and septic shock (IRR 5.62 [95% confidence interval 1.92-16.4], p = 0.002) compared with recipients of MBL-deficient livers. The 1-year bacterial infection-related mortality was higher in recipients of MBL-deficient versus MBL-sufficient livers (65.8% vs. 56.1%, respectively; p = 0.0097). The incidence of rejection, viral, or fungal infection was similar in both groups. Recipient MBL2 genotype did not significantly increase the risk of bacterial infection. LT recipients of MBL-deficient livers have a higher risk of bacterial infection, pneumonia, septic shock, and 1-year bacterial infection-related mortality after LT.


Assuntos
Infecções Bacterianas/mortalidade , Rejeição de Enxerto/mortalidade , Transplante de Fígado/mortalidade , Lectina de Ligação a Manose/genética , Polimorfismo Genético , Complicações Pós-Operatórias , Doadores de Tecidos , Adulto , Idoso , Infecções Bacterianas/etiologia , Infecções Bacterianas/patologia , Feminino , Seguimentos , Predisposição Genética para Doença , Genótipo , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto , Humanos , Transplante de Fígado/efeitos adversos , Masculino , Lectina de Ligação a Manose/deficiência , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco , Taxa de Sobrevida
12.
J Dairy Sci ; 100(7): 5434-5448, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28501404

RESUMO

The objectives of this study were to measure performance responses and to evaluate indictors of N utilization in late-lactation cows fed diets with incremental reductions in crude protein (CP) concentration. Holstein cows (n = 128; 224 ± 54 d in milk) were stratified by parity and days pregnant (86 ± 25 d) and randomly assigned to 1 of 16 pens in a randomized complete block design. For 3 wk, all cows received a covariate diet containing 16.9% CP [dry matter (DM) basis]. For the subsequent 12 wk, pens were randomly assigned to 1 of 4 treatments that contained 16.2, 14.4, 13.1, or 11.8% CP (DM basis). Diets were offered once daily and contained 32.5% corn silage, 32.5% alfalfa silage, 13.5% high-moisture corn, and 21.5% concentrate mix. A reduction in dietary CP was achieved by replacing soybean meal with soy hulls in the concentrate mix (DM basis). Dry matter intake, milk urea N (MUN; mg/dL), and the yield of milk urea N (g/d) decreased linearly with dietary CP. Compared with a 16.2% CP diet, a 14.4% CP diet did not alter milk yield throughout the study, but the 13.1 and 11.8% CP diets reduced milk yield after 4 and 1 wk, respectively. Furthermore, milk protein percentage was reduced for all dietary CP less than 16.2%, but this negative effect was temporary and disappeared after 7 wk for the 14.4% CP diet. In contrast, MUN adjusted to a new steady state within 1 wk for all dietary treatments. Modeling quadratic responses with a plateau led to predictions of no reduction in fat- and protein-corrected milk (32.6 kg/d) and yields of fat (1.31 kg/d), lactose (1.49 kg/d), and true protein (1.12 kg/d) until dietary CP decreased below 15.5, 15.3, 15.9, and 16.2%, respectively. In this study, MUN and the yield of MUN were highly correlated with N intake, milk protein yield, and fat- and protein-corrected milk. Surprisingly, N use efficiency (milk protein N/intake N) was not correlated with any variables related to N utilization and reached an apparent upper limit of approximately 30%. Although this observation may be associated with feeding diets deficient in metabolizable protein, late-lactation cows in this study adjusted to low dietary CP concentration better than anticipated as milk production was 2.6, 3.6, 6.4, and 8.0 kg/d higher than National Research Council (2001)-predicted metabolizable protein-allowable milk for dietary CP of 16.2, 14.4, 13.1, and 11.8%, respectively.


Assuntos
Dieta/veterinária , Proteínas Alimentares/farmacologia , Lactação , Nitrogênio/metabolismo , Silagem , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos , Proteínas Alimentares/administração & dosagem , Feminino , Leite/química , Paridade , Gravidez , Distribuição Aleatória , Rúmen , Zea mays
13.
J Chem Phys ; 146(11): 114502, 2017 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-28330358

RESUMO

We have investigated the Debye-like relaxation in a series of monoalcohols (MAs) by broadband dielectric spectroscopy and thermally stimulated depolarization current techniques in order to get further insight on the time dispersion of this intriguing relaxation. Results indicate that the Debye-like relaxation of MAs is not always of exponential type and conforms well to a dispersion of Cole-Davidson type. Apart from the already reported non-exponentiality of the Debye-like relaxation in 2-hexyl-1-decanol and 2-butyl-1-octanol, a detailed analysis of the dielectric permittivity of 5-methyl-3-heptanol shows that this MA also presents some extent of dispersion on its Debye-like relaxation which strongly depends on the temperature. Results suggest that the non-exponential character of the Debye-like relaxation might be a general characteristic in the case of not so intense Debye-like relaxations relative to the α relaxation. Finally, we briefly discuss on the T-dependence and possible origin for the observed dispersion.

14.
Phys Rev Lett ; 117(18): 185501, 2016 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-27834987

RESUMO

The analysis of neutron scattering results on H dynamics (H_{2}O) and the dynamic structure factor (D_{2}O) around the intermolecular peak and at intermediate length scales in terms of the susceptibilities reveals three processes (diffusive, local relaxational and vibrational) at frequencies below 3 THz, to which the contributions commonly invoked in dielectric studies can be directly mapped. We achieve a unified description of the results from both techniques, clarifying the nature of the molecular motions involved in the dielectric spectra and their impact on the structural relaxation.

15.
J Chem Phys ; 144(15): 154903, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27389236

RESUMO

We have combined X-ray diffraction, neutron diffraction with polarization analysis, small angle neutron scattering,differential scanning calorimetry, and broad band dielectric spectroscopy to investigate the structure and dynamics of binary mixtures of poly(2-(dimethylamino)ethyl methacrylate) with either water or tetrahydrofuran (THF) at different concentrations. Aqueous mixtures are characterized by a highly heterogeneous structure where water clusters coexist with an underlying nano-segregation of main chains and side groups of the polymeric matrix. THF molecules are homogeneously distributed among the polymeric nano-domains for concentrations of one THF molecule/monomer or lower. A more heterogeneous situation is found for higher THF amounts, but without evidences for solvent clusters. In THF-mixtures, we observe a remarkable reduction of the glass-transition temperature which is enhanced with increasing amount of solvent but seems to reach saturation at high THF concentrations. Adding THF markedly reduces the activation energy of the polymer ß-relaxation. The presence of THF molecules seemingly hinders a slow component of this process which is active in the dry state. The aqueous mixtures present a strikingly broad glass-transition feature, revealing a highly heterogeneous behavior in agreement with the structural study. Regarding the solvent dynamics, deep in the glassy state all data can be described by an Arrhenius temperature dependence with a rather similar activation energy. However, the values of the characteristic times are about three orders of magnitude smaller for THF than for water. Water dynamics display a crossover toward increasingly higher apparent activation energies in the region of the onset of the glass transition, supporting its interpretation as a consequence of the freezing of the structuralrelaxation of the surrounding matrix. The absence of such a crossover (at least in the wide dynamic window here accessed) in THF is attributed to the lack of cooperativity effects in the relaxation of these molecules within the polymeric matrix.

16.
Actas urol. esp ; 40(4): 263-267, mayo 2016. ilus
Artigo em Espanhol | IBECS | ID: ibc-151379

RESUMO

Antecedentes: El cáncer vesical es la segunda malignidad más común del tracto urinario y la novena a nivel mundial, en Latinoamérica con incidencia de 5.6 por cada 100.000 habitantes por año. El 75% de casos nuevos diagnosticados son cáncer vesical no musculoinvasivos y el 25% se presenta con invasión muscular. El pilar del tratamiento del cáncer vesical no musculoinvasivo es la resección transuretral con asa. En 2013 el grupo del Dr. Mundhenk del Hospital Universitario de Tübingen, Alemania, fueron los primeros en describir el equipo Hybrid Knife(R) para realizar resección de tumor vesical en bloque con resultados funcionales y oncológicos favorables. Objetivo: Describir la técnica quirúrgica de resección de tumor vesical en bloque con Hybrid Knife(R) como alternativa de tratamiento para los tumores vesicales no musculoinvasivos. Material y métodos: Varón con tumor vesical diagnosticado por urotomografía y uretrocistoscopia de 2 × 1 cm en piso, se realizó resección transuretral de tumor vesical en bloque con Hybrid Knife(R). Resultados: Se realizó cirugía, en 35 min, con 70 watts en corte y 50 watts en coagulación, resecando y evacuando en bloque el tumor vesical incluyendo macroscópicamente capa muscular de la vejiga, sin complicaciones. Conclusión: La técnica de resección de tumor vesical en bloque con Hybrid Knife(R) es una alternativa eficaz a la resección transuretral con asa bipolar. La resección con Hybrid Knife(R) es un procedimiento con escaso sangrado, buena visión quirúrgica, minimizando el riesgo de perforación vesical o implantes tumorales con mayor facilidad para lograr determinar positividad de proceso neoplásico, infiltración vascular e invasión a músculo vesical en estudio histopatológico


Background: Bladder cancer is the second most common malignancy of the urinary tract and the 9 th worldwide. Latin American has an incidence of 5.6 per 100,000 inhabitants per year. Seventy-five percent of newly diagnosed cases are nonmuscle invasive bladder cancer, and 25% of cases present as muscle invasive. The mainstay of treatment for nonmuscle invasive bladder cancer is loop transurethral resection. In 2013, the group led by Dr Mundhenk of the University Hospital of Tübingen, Germany, was the first to describe the Hybrid Knife(R) equipment for performing en bloc bladder tumour resection, with favourable functional and oncological results. Objective: To describe the surgical technique of en bloc bladder tumour resection with a Hybrid Knife(R) as an alternative treatment for nonmuscle invasive bladder tumours. Material and methods A male patient was diagnosed by urotomography and urethrocystoscopy with a bladder tumour measuring 2 × 1 cm on the floor. En bloc transurethral resection of the bladder tumour was performed with a Hybrid Knife(R). Results: Surgery was performed for 35 min, with 70 watts for cutting and 50 watts for coagulation, resecting and evacuating en bloc the bladder tumour, which macroscopically included the muscle layer of the bladder. There were no complications. Conclusion: The technique of en bloc bladder tumour resection with Hybrid Knife® is an effective alternative to bipolar loop transurethral resection. Resection with a Hybrid Knife(R) is a procedure with little bleeding and good surgical vision and minimises the risk of bladder perforation and tumour implants. The procedure facilitates determining the positivity of the neoplastic process, vascular infiltration and bladder muscle invasion in the histopathology study


Assuntos
Humanos , Masculino , Idoso de 80 Anos ou mais , Cistectomia/instrumentação , Cistectomia/métodos , Neoplasias da Bexiga Urinária/cirurgia , Desenho de Equipamento , Uretra
17.
Osteoporos Int ; 27(8): 2631-4, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27010647

RESUMO

Non-uremic calciphylaxis is a severe rare disorder characterized by ischemic necrosis. Recently, three cases of cutaneous calciphylaxis have been described in the context of teriparatide treatment. We present a 51-year-old woman with alcoholic cirrhosis who developed multiorganic calciphylaxis shortly after starting teriparatide treatment associated with calcium and 25-hydroxyvitamin D supplements for severe osteoporosis. After lengthy care of the infectious complications and treatment with bisphosphonates and sodium thiosulfate progressive improvement was observed over a 3-year period. The time between the initiation of teriparatide and the development of calciphylaxis suggests that this agent may have been the triggering factor of this process. Nevertheless, other non-negligible risk factors for calciphylaxis such as alcoholic liver disease, obesity, and vitamin D treatment must also be considered in this patient. Considering the severity of this extremely rare clinical condition, better knowledge of the risk factors related to calciphylaxis development is mandatory.


Assuntos
Calciofilaxia/induzido quimicamente , Cálcio/administração & dosagem , Teriparatida/efeitos adversos , Vitamina D/análogos & derivados , Feminino , Humanos , Pessoa de Meia-Idade , Teriparatida/administração & dosagem , Vitamina D/administração & dosagem
18.
Actas Urol Esp ; 40(4): 263-7, 2016 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26708386

RESUMO

BACKGROUND: Bladder cancer is the second most common malignancy of the urinary tract and the 9th worldwide. Latin American has an incidence of 5.6 per 100,000 inhabitants per year. Seventy-five percent of newly diagnosed cases are nonmuscle invasive bladder cancer, and 25% of cases present as muscle invasive. The mainstay of treatment for nonmuscle invasive bladder cancer is loop transurethral resection. In 2013, the group led by Dr Mundhenk of the University Hospital of Tübingen, Germany, was the first to describe the Hybrid Knife(®) equipment for performing en bloc bladder tumour resection, with favourable functional and oncological results. OBJECTIVE: To describe the surgical technique of en bloc bladder tumour resection with a Hybrid Knife(®) as an alternative treatment for nonmuscle invasive bladder tumours. MATERIAL AND METHODS: A male patient was diagnosed by urotomography and urethrocystoscopy with a bladder tumour measuring 2×1cm on the floor. En bloc transurethral resection of the bladder tumour was performed with a Hybrid Knife(®). RESULTS: Surgery was performed for 35min, with 70 watts for cutting and 50 watts for coagulation, resecting and evacuating en bloc the bladder tumour, which macroscopically included the muscle layer of the bladder. There were no complications. CONCLUSION: The technique of en bloc bladder tumour resection with Hybrid Knife(®) is an effective alternative to bipolar loop transurethral resection. Resection with a Hybrid Knife(®) is a procedure with little bleeding and good surgical vision and minimises the risk of bladder perforation and tumour implants. The procedure facilitates determining the positivity of the neoplastic process, vascular infiltration and bladder muscle invasion in the histopathology study.


Assuntos
Cistectomia/instrumentação , Cistectomia/métodos , Neoplasias da Bexiga Urinária/cirurgia , Idoso de 80 Anos ou mais , Desenho de Equipamento , Humanos , Masculino , Uretra
19.
J Chem Phys ; 143(9): 094505, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26342375

RESUMO

We have investigated a mixture of poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) and tetrahydrofuran (THF) (70 wt. % PDMAEMA/30 wt. % THF) by combining dielectric spectroscopy and quasielastic neutron scattering (QENS) on a labelled sample, focusing on the dynamics of the THF molecules. Two independent processes have been identified. The "fast" one has been qualified as due to an internal motion of the THF ring leading to hydrogen displacements of about 3 Å with rather broadly distributed activation energies. The "slow" process is characterized by an Arrhenius-like temperature dependence of the characteristic time which persists over more than 9 orders of magnitude in time. The QENS results evidence the confined nature of this process, determining a size of about 8 Å for the volume within which THF hydrogens' motions are restricted. In a complementary way, we have also investigated the structural features of the sample. This study suggests that THF molecules are well dispersed among side-groups nano-domains in the polymer matrix, ruling out a significant presence of clusters of solvent. Such a good dispersion, together with a rich mobility of the local environment, would prevent cooperativity effects to develop for the structural relaxation of solvent molecules, frustrating thereby the emergence of Vogel-Fulcher-like behavior, at least in the whole temperature interval investigated.

20.
J Chem Phys ; 142(21): 214504, 2015 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-26049505

RESUMO

We explore new routes for characterizing the Debye-like and α relaxation in 2-ethyl-1-hexanol (2E1H) monoalcohol by using low frequency dielectric techniques including thermally stimulated depolarization current (TSDC) techniques and isothermal depolarization current methods. In this way, we have improved the resolution of the overlapped processes making it possible the analysis of the data in terms of a mode composition as expected for a chain-like response. Furthermore the explored ultralow frequencies enabled to study dynamics at relatively low temperatures close to the glass transition (Tg). Results show, on the one hand, that Debye-like and α relaxation timescales dramatically approach to each other upon decreasing temperature to Tg. On the other hand, the analysis of partial polarization TSDC data confirms the single exponential character of the Debye-like relaxation in 2E1H and rules out the presence of Rouse type modes in the scenario of a chain-like response. Finally, on crossing the glass transition, the Debye-like relaxation shows non-equilibrium effects which are further emphasized by aging treatment and would presumably emerge as a result of the arrest of the structural relaxation below Tg.


Assuntos
Vidro/química , Hexanóis/química , Temperatura , Elétrons
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