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1.
Actas urol. esp ; 46(9): 572-576, nov. 2022. tab
Artigo em Espanhol | IBECS | ID: ibc-211500

RESUMO

Objetivo: Se ha descrito que la timoglobulina podría aumentar el riesgo de infecciones y neoplasias, en comparación con basiliximab. La leucocitopenia y la trombocitopenia también son más frecuentes en los primeros días tras el trasplante en los pacientes tratados con timoglobulina.Nuestro objetivo fue analizar las complicaciones hemorrágicas en este subconjunto de pacientes.Material y métodos: Se evaluaron las complicaciones hemorrágicas en 515 trasplantes renales realizados en nuestra institución entre 2012 y 2018. Se comparó a los pacientes tratados con timoglobulina (grupo 1, N=91) con los tratados con basiliximab (grupo 2, N=424).Resultados: Encontramos diferencias en cuanto al descenso plaquetario: 95.142,2 (55.339,6) en el grupo 1 y 52.364,3 (69.116,6) en el grupo 2 (p=0,001), número de pacientes con trombocitopenia grave (< 7.5000/mm3) (20,8% vs. 3,7%, p=0,001), número de concentrados de hematíes transfundidos (3,25 [0,572] vs. 2,2 [0,191], p=0,028) y porcentaje de pacientes que requirieron reintervención por sangrado (18,2% vs. 7,7%, p=0,046). En un análisis multivariable de regresión lineal múltiple (la variable dependiente fue el número de concentrado de hematíes transfundidos), solo la edad (OR 0,037, IC del 95%, 0,003-0,070) y el tipo de inmunosupresión (OR 1,592, IC del 95%, 1,38-2,84) tuvieron significación estadística.Conclusiones: El uso de timoglobulina en el período perioperatorio del trasplante podría aumentar las complicaciones hemorrágicas. En nuestra serie, la trombocitopenia grave y el sangrado activo que requirió reintervención, fueron 6 y 2,5 veces más frecuente, respectivamente, en el grupo de pacientes con timoglobulina. En lugar de suspender el uso de este agente inmunosupresor, se podría ajustar la dosis para continuar con el tratamiento.Se debe evaluar el uso de timoglobulina en el postoperatorio de estos pacientes (AU)


Objective: It has been described that thymoglobulin could increase the risk of infections and malignancies, in comparison to basiliximab. Leukopenia and thrombocytopenia are also more common within the first days after transplantation among thymoglobulin patients. Our objective was to analyze bleeding complications in this subset of patients.Material and methods: Bleeding complications were evaluated among 515 renal transplants carried out at our institution between 2012 and 2018. We compared patients treated with thymoglobulin (Group 1, N=91) with those treated with basiliximab (Group 2, N=424).Results: We found differences in platelet decrease:95142.2 (55,339.6) in Group 1 and 52,364.3 (69,116.6) in Group 2 (P=.001), number of patients with severe thrombocytopenia (<75,000/mm3) (20.8% vs. 3.7%, P=.001), number of blood units transfused (3.25 (0.572) vs. 2.2 (0.191, P=.028) and percentage of patients that required surgery due to bleeding (18.2% vs. 7.7%, P=.046). In a multiple lineal regression multivariable analysis (dependent variable was number of blood units transfused), only age [OR 0.037, 95% CI (0.003-0.070)] and type of immunosuppression [OR 1.592, 95% CI (1.38-2.84)] showed statistical significance.Conclusions: The use of thymoglobulin in the perioperative transplantation period could increase bleeding complications. In our series, in the group of patients with thymoglobulin, severe thrombocytopenia was 6 times more frequent, and active bleeding that required surgery was also 2.5 times more frequent. One way to continue with the use of this immunosuppression agent, might be to adjust the dose instead of discontinuing it. The use of thymoglobulin should be a factor to consider in the postoperative period of these patients (AU)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Anticorpos Monoclonais/uso terapêutico , Basiliximab/uso terapêutico , Imunossupressores/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Transplante de Rim/efeitos adversos , Hemorragia/induzido quimicamente , Hemorragia/prevenção & controle , Estudos Retrospectivos
2.
Actas Urol Esp (Engl Ed) ; 46(9): 572-576, 2022 11.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35717440

RESUMO

OBJECTIVE: It has been described that thymoglobulin could increase the risk of infections and malignancies, in comparison to basiliximab. Leukopenia and thrombocytopenia are also more common within the first days after transplantation among thymoglobulin patients. Our objective was to analyze bleeding complications in this subset of patients. MATERIAL AND METHODS: Bleeding complications were evaluated among 515 renal transplants carried out at our institution between 2012 and 2018. We compared patients treated with thymoglobulin (Group 1, N=91) with those treated with basiliximab (Group 2, N=424). RESULTS: We found differences in platelet decrease: 95,142.2 (55,339.6) in Group 1 and 52,364.3 (69,116.6) in Group 2 (P=0.001), number of patients with severe thrombocytopenia (<75,000/mm3) (20.8% vs. 3.7%, P=0.001), number of blood units transfused (3.25 (0.572) vs. 2.2 (0.191, P=0.028) and percentage of patients that required surgery due to bleeding (18.2% vs. 7.7%, P=0.046). In a multiple lineal regression multivariable analysis (dependent variable was number of blood units transfused), only age [OR 0.037, 95% CI (0.003-0.070)] and type of immunosuppression [OR 1.592, 95% CI (1.38-2.84)] showed statistical significance. CONCLUSIONS: The use of thymoglobulin in the perioperative transplantation period could increase bleeding complications. In our series, in the group of patients with thymoglobulin, severe thrombocytopenia was 6 times more frequent, and active bleeding that required surgery was also 2.5 times more frequent. One way to continue with the use of this immunosuppression agent, might be to adjust the dose instead of discontinuing it. The use of thymoglobulin should be a factor to consider in the postoperative period of these patients.


Assuntos
Rejeição de Enxerto , Trombocitopenia , Humanos , Basiliximab/efeitos adversos , Anticorpos Monoclonais/uso terapêutico , Estudos Retrospectivos , Rim , Trombocitopenia/tratamento farmacológico
3.
Actas urol. esp ; 45(6): 455-460, julio-agosto 2021. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-216999

RESUMO

Introducción y objetivo: La mayoría de los cánceres de próstata (CP) se clasifican como adenocarcinoma acinar. El carcinoma intraductal de la próstata (CIDP) es una entidad histológica distinta que se cree que representa la propagación retrógrada del adenocarcinoma acinar invasivo en los conductos prostáticos y acinos.Hemos analizado el impacto del CIDP en pacientes con cáncer de próstata resistente a la castración metastásico (CPRCm) y sin tratamiento hormonal previo (hormone-naïve).Pacientes y métodosEvaluamos retrospectivamente a 118 pacientes con CPRCm con diagnóstico inicial de cáncer de prostata metastásico (CPM) desde mayo del 2010 hasta septiembre del 2018. El grupo uno incluyó 81 personas con CPM con adenocarcinoma acinar y el grupo dos estuvo compuesto por 37 pacientes con CPM con CIDP.ResultadosLa edad media de presentación fue de 76 años (IQR 73,4 a 78,7) en el grupo uno y de 74 años (68,5 a 80,6) en el grupo dos. El valor medio del PSA en el momento del diagnóstico fue de 619 ng/mL (IQR 85 a 1.113) y 868 ng/mL (IQR 186 a 1.922), respectivamente. El tiempo hasta la resistencia a la castración fue de 24,7 meses (IQR 16,7 a 32,7) en el grupo uno y 10,2 meses (IQR 4,2 a 16,2) en el grupo dos (p = 0,007). El tiempo hasta la progresión en los pacientes con cáncer de próstata resistente a la castración (CPRC) fue: 10,6 meses (IQR 5,6 a 15,6) y 6,2 meses (3,2 a 9,2), respectivamente (p = 0,05). La supervivencia global fue de 57,9 meses en el grupo uno (IC 95% 56,4 a 59,5) y de 38 meses (IC 95% 19,9 a 48,06) en el grupo dos (p = 0,001). En el análisis multivariante, el subtipo de adenocarcinoma fue estadísticamente significativo p 0,014, IC 95% (Hazard Ratio [HR] 0,058, 0,006 a 0,56).ConclusionesEl CIDP parece ser un subtipo de CP que se asocia con una respuesta más corta al tratamiento hormonal cuando se compara con el adenocarcinoma acinar en pacientes con cáncer metastásico. (AU)


Introduction and objective: Most prostate cancers are classified as acinar adenocarcinoma. Intraductal carcinoma of the prostate (IDC-P) is a distinct histologic entity that is believed to represent retrograde spread of invasive acinar adenocarcinoma into prostatic ducts and acini.We have analyzed the impact of IDC-P in hormonal naïve and castration resistant metastatic prostate cancer patients.Patients and methodsWe retrospectively evaluated 118 metastatic castration resistant prostate cancer (mCRPC) patients who were initially diagnosed with distant metastases from May 2010 to September 2018. Group 1 patients included 81 metastatic PCa patients with acinar adenocarcinoma and Group 2 included 37 metastatic PCa patients with IDC-P.ResultsMean age at presentation was 76 years (IQR 73.4-78.7) in group 1 and 74 years (68.5-80.6) in group 2. Mean PSA at diagnosis was 619 ng/mL (IQR 85-1113) and 868 ng/mL (IQR 186-1922), respectively. Time to castration resistance was 24.7 months (IQR 16.7-32.7) in group 1 and 10.2 months (IQR 4.2-16.2) in group 2 (p = 0.007). Time to progression in CPRC patients was: 10.6 months (IQR 5.6-15.6) and at 6.2 months (3.2-9.2), respectively (p = 0.05). Overall survival was 57.9 months in group 1(CI 95% 56.4-59.5) and 38 months (CI 95% 19.9-48.06) in group 2 (p = 0.001). In the multivariate analysis, adenocarcinoma subtype was statistically significant p 0.014, CI 95% (HR 0.058, 0.006-0.56).ConclusionsIDC-P seems to be a subtype of prostate cancer that is associated with a shorter response to hormonal treatment when compared to acinar adenocarcinoma in metastatic patients. New drugs in CRPC scenario as abiraterone and enzalutamide also obtained less response in IDC-P patients. In daily clinical practice it might be interesting to take into account that patients with IDC-P may present shorter responses to first and second line hormonal treatments. (AU)


Assuntos
Humanos , Carcinoma Intraductal não Infiltrante , Feniltioidantoína , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Estudos Retrospectivos
4.
Actas Urol Esp (Engl Ed) ; 45(6): 455-460, 2021.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34147428

RESUMO

INTRODUCTION AND OBJECTIVE: Most prostate cancers are classified as acinar adenocarcinoma. Intraductal carcinoma of the prostate (IDC-P) is a distinct histologic entity that is believed to represent retrograde spread of invasive acinar adenocarcinoma into prostatic ducts and acini. We have analyzed the impact of IDC-P in hormonal naïve and castration resistant metastatic prostate cancer patients. PATIENTS AND METHODS: We retrospectively evaluated 118 metastatic castration resistant prostate cancer (mCRPC) patients who were initially diagnosed with distant metastases from May 2010 to September 2018. Group 1 patients included 81 metastatic PCa patients with acinar adenocarcinoma and Group 2 included 37 metastatic PCa patients with IDC-P. RESULTS: Mean age at presentation was 76 years (IQR 73.4-78.7) in group 1 and 74 years (68.5-80.6) in group 2. Mean PSA at diagnosis was 619 ng/mL (IQR 85-1113) and 868 ng/mL (IQR 186-1922), respectively. Time to castration resistance was 24.7 months (IQR 16.7-32.7) in group 1 and 10.2 months (IQR 4.2-16.2) in group 2 (P = .007). Time to progression in CPRC patients was: 10.6 months (IQR 5.6-15.6) and at 6.2 months (3.2-9.2), respectively (P = .05). Overall survival was 57.9 months in group 1(CI 95% 56.4-59.5) and 38 months (CI 95% 19.9-48.06) in group 2 (P = .001). In the multivariate analysis, adenocarcinoma subtype was statistically significant P .014, CI 95% (HR 0.058, 0.006-0.56) CONCLUSIONS: IDC-P seems to be a subtype of prostate cancer that is associated with a shorter response to hormonal treatment when compared to acinar adenocarcinoma in metastatic patients. New drugs in CRPC scenario as abiraterone and enzalutamide also obtained less response in IDC-P patients. Once IDC-P is identified, clinicians could extrapolate the relative poor response to hormonal therapy. Consequently, follow-up of these patients in this scenario should be more strict.


Assuntos
Carcinoma Intraductal não Infiltrante , Neoplasias de Próstata Resistentes à Castração , Humanos , Masculino , Feniltioidantoína , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Estudos Retrospectivos
6.
Nat Mater ; 20(2): 194-201, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33046856

RESUMO

Topological solitons such as magnetic skyrmions have drawn attention as stable quasi-particle-like objects. The recent discovery of polar vortices and skyrmions in ferroelectric oxide superlattices has opened up new vistas to explore topology, emergent phenomena and approaches for manipulating such features with electric fields. Using macroscopic dielectric measurements, coupled with direct scanning convergent beam electron diffraction imaging on the atomic scale, theoretical phase-field simulations and second-principles calculations, we demonstrate that polar skyrmions in (PbTiO3)n/(SrTiO3)n superlattices are distinguished by a sheath of negative permittivity at the periphery of each skyrmion. This enhances the effective dielectric permittivity compared with the individual SrTiO3 and PbTiO3 layers. Moreover, the response of these topologically protected structures to electric field and temperature shows a reversible phase transition from the skyrmion state to a trivial uniform ferroelectric state, accompanied by large tunability of the dielectric permittivity. Pulsed switching measurements show a time-dependent evolution and recovery of the skyrmion state (and macroscopic dielectric response). The interrelationship between topological and dielectric properties presents an opportunity to simultaneously manipulate both by a single, and easily controlled, stimulus, the applied electric field.

7.
Nature ; 568(7752): 368-372, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30996320

RESUMO

Complex topological configurations are fertile ground for exploring emergent phenomena and exotic phases in condensed-matter physics. For example, the recent discovery of polarization vortices and their associated complex-phase coexistence and response under applied electric fields in superlattices of (PbTiO3)n/(SrTiO3)n suggests the presence of a complex, multi-dimensional system capable of interesting physical responses, such as chirality, negative capacitance and large piezo-electric responses1-3. Here, by varying epitaxial constraints, we discover room-temperature polar-skyrmion bubbles in a lead titanate layer confined by strontium titanate layers, which are imaged by atomic-resolution scanning transmission electron microscopy. Phase-field modelling and second-principles calculations reveal that the polar-skyrmion bubbles have a skyrmion number of +1, and resonant soft-X-ray diffraction experiments show circular dichroism, confirming chirality. Such nanometre-scale polar-skyrmion bubbles are the electric analogues of magnetic skyrmions, and could contribute to the advancement of ferroelectrics towards functionalities incorporating emergent chirality and electrically controllable negative capacitance.

8.
Nat Mater ; 16(10): 1003-1009, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28783161

RESUMO

Systems that exhibit phase competition, order parameter coexistence, and emergent order parameter topologies constitute a major part of modern condensed-matter physics. Here, by applying a range of characterization techniques, and simulations, we observe that in PbTiO3/SrTiO3 superlattices all of these effects can be found. By exploring superlattice period-, temperature- and field-dependent evolution of these structures, we observe several new features. First, it is possible to engineer phase coexistence mediated by a first-order phase transition between an emergent, low-temperature vortex phase with electric toroidal order and a high-temperature ferroelectric a1/a2 phase. At room temperature, the coexisting vortex and ferroelectric phases form a mesoscale, fibre-textured hierarchical superstructure. The vortex phase possesses an axial polarization, set by the net polarization of the surrounding ferroelectric domains, such that it possesses a multi-order-parameter state and belongs to a class of gyrotropic electrotoroidal compounds. Finally, application of electric fields to this mixed-phase system permits interconversion between the vortex and the ferroelectric phases concomitant with order-of-magnitude changes in piezoelectric and nonlinear optical responses. Our findings suggest new cross-coupled functionalities.

9.
Actas Urol Esp ; 39(9): 582-7, 2015 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26255076

RESUMO

OBJECTIVE: Cryotherapy is a minimally invasive ablative technique that is considered an alternative to conventional surgery for preserving renal function in small renal tumors and in selected cases. We present our results from laparoscopic renal cryotherapy. MATERIAL AND METHOD: We retrospectively analyzed 17 renal tumors diagnosed in 16 patients treated with cryotherapy. The patients' mean age was 66 years (43-80). The mean tumor size was 1.8cm (0.7-3.7cm). Cryotherapy with double-freeze cycle was performed laparoscopically in all cases (10 by transperitoneal approach and 7 by retroperitoneal approach). RESULTS: Perioperative biopsies were performed on all patients and were positive for malignancy in 10 cases (59%). The mean stay was 2.8 days. The mean operative time was 162 minutes. Only 1 case reverted to open surgery due to bleeding. One patient required a blood transfusion in the immediate postoperative period. The majority of complications were Clavien-Dindo grades I and II. Some 76.5% of the patients had no complications. After a mean follow-up of 31 months (6-102), 1 patient died from nontumor-related causes, and 12 patients (75%) still show no evidence of local recurrence or progression. One patient had tumor persistence and therefore underwent partial nephrectomy at 6 months. One patient had a metachronous recurrence in the same kidney at 36 months, and another patient had a recurrence at 23 months. CONCLUSIONS: Laparoscopic renal cryotherapy is a safe and feasible technique and is a good alternative to surgery for selected renal tumors.


Assuntos
Criocirurgia/métodos , Neoplasias Renais/cirurgia , Laparoscopia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peritônio , Espaço Retroperitoneal , Estudos Retrospectivos
10.
Nat Commun ; 5: 4530, 2014 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-25088659

RESUMO

Complex oxide heterostructures display some of the most chemically abrupt, atomically precise interfaces, which is advantageous when constructing new interface phases with emergent properties by juxtaposing incompatible ground states. One might assume that atomically precise interfaces result from stoichiometric growth. Here we show that the most precise control is, however, obtained by using deliberate and specific non-stoichiometric growth conditions. For the precise growth of Sr(n+1)Ti(n)O(n+1) Ruddlesden-Popper (RP) phases, stoichiometric deposition leads to the loss of the first RP rock-salt double layer, but growing with a strontium-rich surface layer restores the bulk stoichiometry and ordering of the subsurface RP structure. Our results dramatically expand the materials that can be prepared in epitaxial heterostructures with precise interface control--from just the n = ∞ end members (perovskites) to the entire RP homologous series--enabling the exploration of novel quantum phenomena at a richer variety of oxide interfaces.

12.
Actas urol. esp ; 37(1): 47-53, ene. 2013. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-108451

RESUMO

Objetivo: Presentar nuestra experiencia en el control hemostático de la nefrectomía parcial laparoscópica utilizando un compuesto de fibrina autóloga (Vivostat system®), sin reconstrucción del parénquima renal. Material y métodos: Hemos realizado 45 nefrectomías parciales utilizando este agente hemostático. Los principales pasos quirúrgicos fueron: decolación, identificación del uréter, hilio y tumoración renal, control de la arteria renal con torniquete de Rummel, exéresis tumoral con bisturí armónico y aplicación del sellador de fibrina en el lecho quirúrgico en 2 fases (antes y después de la reperfusión renal). Se registraron datos de sangrado precoz o diferido. Resultados: Edad media: 63,9 años (33-80); tamaño medio del tumor 2,5cm (1,5-4); tiempo medio quirúrgico: 136,1minutos (90-180). Tiempo medio de isquemia caliente 19,2minutos (10-30). Pérdida sanguínea media: 97ml (50-300). Se realizaron puntos hemostáticos individuales antes de la aplicación del sellador de fibrina, en caso de sangrado activo importante (14 casos). No se registró ningún caso de sangrado ni fallo renal en el postoperatorio. Un paciente requirió transfusión sanguínea debido a gran hematoma en pared abdominal. El 65% fue carcinoma de célula clara renal, el 10% carcinoma papilar y un 20% fueron oncocitomas. La tasa de márgenes negativos fue del 100%. El tiempo medio de ingreso hospitalario fue 4 días (2-6). El seguimiento medio fue de 14 meses (5-45). Conclusiones: Excluir la renorrafia durante la nefrectomía parcial laparoscópica es posible y seguro. Nuestra experiencia inicial con este sellador de fibrina ha sido positiva, aunque probablemente se necesiten más casos y seguimiento para determinar el beneficio de esta técnica quirúrgica (AU)


Objective: To present our experience using an autologous fibrin sealant prepared with the Vivostat system® to control haemostasis without any renal parenchymal reconstruction. Material and methods: We performed 45 laparoscopic partial nephrectomies using this haemostatic agent. The surgical steps were: colon mobilization, identification of ureter, renal vessels and renal tumor, renal artery control with Rummel tourniquet, tumor excision with harmonic scalpel, application of fibrin glue to the resection bed twice (before and after kidney reperfusion). Patients were evaluated for acute or delayed bleeding. Results: Mean age was 63.9 years (33-80); mean tumor size was 2.5cm (1.5-4); mean operative time was 136.1min (90-180). Mean warm ischemia time was 19.2min (10-30). Mean blood loss was 97ml (50-300). Individual haemostatic stitches were performed before application of the sealant if acute bleeding was observed (14 cases). We did not achieve any case of postoperative bleeding from resection bed or renal failure. 1 patient required transfusion due to an abdominal wall haematoma. 65% were clear cell carcinoma, 10% were papillary carcinoma, 20% were oncocitoma. Free margin rate was 100%. Mean hospital stay was 4 days (2-6). Mean follow-up was 14 months (5-45). Conclusions: Excluding renorrhaphy during laparoscopic partial nephrectomy is feasible and safe. Our initial experience with the vivostat system in laparoscopic partial nephrectomy has been encouraging, but longer follow-up is needed to determine the real benefit of this surgical technique in laparoscopic partial nephrectomy (AU)


Assuntos
Humanos , Hemostasia Cirúrgica/métodos , Nefrectomia/métodos , Laparoscopia/métodos , Perda Sanguínea Cirúrgica/prevenção & controle , Neoplasias Renais/cirurgia , Fibrina/uso terapêutico , Carcinoma de Células Renais/cirurgia
13.
Actas Urol Esp ; 37(1): 47-53, 2013 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-22819491

RESUMO

OBJECTIVE: To present our experience using an autologous fibrin sealant prepared with the Vivostat system(®) to control haemostasis without any renal parenchymal reconstruction. MATERIAL AND METHODS: We performed 45 laparoscopic partial nephrectomies using this haemostatic agent. The surgical steps were: colon mobilization, identification of ureter, renal vessels and renal tumor, renal artery control with Rummel tourniquet, tumor excision with harmonic scalpel, application of fibrin glue to the resection bed twice (before and after kidney reperfusion). Patients were evaluated for acute or delayed bleeding. RESULTS: Mean age was 63.9 years (33-80); mean tumor size was 2.5cm (1.5-4); mean operative time was 136.1min (90-180). Mean warm ischemia time was 19.2min (10-30). Mean blood loss was 97ml (50-300). Individual haemostatic stitches were performed before application of the sealant if acute bleeding was observed (14 cases). We did not achieve any case of postoperative bleeding from resection bed or renal failure. 1 patient required transfusion due to an abdominal wall haematoma. 65% were clear cell carcinoma, 10% were papillary carcinoma, 20% were oncocitoma. Free margin rate was 100%. Mean hospital stay was 4 days (2-6). Mean follow-up was 14 months (5-45). CONCLUSIONS: Excluding renorrhaphy during laparoscopic partial nephrectomy is feasible and safe. Our initial experience with the vivostat system in laparoscopic partial nephrectomy has been encouraging, but longer follow-up is needed to determine the real benefit of this surgical technique in laparoscopic partial nephrectomy.


Assuntos
Adesivo Tecidual de Fibrina , Hemostasia Cirúrgica/métodos , Cuidados Intraoperatórios/métodos , Neoplasias Renais/cirurgia , Laparoscopia , Nefrectomia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Sistemas de Liberação de Medicamentos/instrumentação , Feminino , Adesivo Tecidual de Fibrina/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
14.
Nano Lett ; 12(6): 2846-51, 2012 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-22591200

RESUMO

The performance of ferroelectric devices is intimately entwined with the structure and dynamics of ferroelectric domains. In ultrathin ferroelectrics, ordered nanodomains arise naturally in response to the presence of a depolarizing field and give rise to highly inhomogeneous polarization and structural profiles. Ferroelectric superlattices offer a unique way of engineering the desired nanodomain structure by modifying the strength of the electrostatic interactions between different ferroelectric layers. Through a combination of X-ray diffraction, transmission electron microscopy, and first-principles calculations, the electrostatic coupling between ferroelectric layers is studied, revealing the existence of interfacial layers of reduced tetragonality attributed to inhomogeneous strain and polarization profiles associated with the domain structure.


Assuntos
Campos Magnéticos , Modelos Químicos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Eletricidade Estática , Simulação por Computador , Condutividade Elétrica , Tamanho da Partícula , Propriedades de Superfície
16.
Actas urol. esp ; 34(7): 586-591, jul.-ago. 2010. tab, ilus, graf
Artigo em Espanhol | IBECS | ID: ibc-81917

RESUMO

El incidentaloma suprarrenal es una entidad en aumento en la práctica clínica habitual debido al gran número de exploraciones radiológicas que se realizan. No existen guías clínicas publicadas sobre el manejo del incidentaloma suprarrenal apoyadas por ninguna sociedad científica. Toda masa suprarrenal debe ser estudiada para descartar malignidad o hipersecreción hormonal. Creemos que la patología suprarrenal quirúrgica debe ser manejada por el urólogo, por ser la especialidad que mayor relación tiene con en el retroperitoneo alto. El objetivo de esta revisión es desarrollar los aspectos fundamentales que el urólogo debe saber en el manejo de las masas suprarrenales. Conjuntamente con el servicio de endocrinología de nuestro hospital describimos los principales estudios a realizar ante el diagnóstico de una masa suprarrenal y el esquema terapéutico vigente en nuestro centro (AU)


Adrenal incidentaloma's prevalence is rising because of the big volume of radiologic explorations that we daily do. No comprehensive guidelines have been published by professional societies to guide the evaluation of patients with adrenal incidentalomas. All adrenal masses should be inspected for malignancy or hypersecreting disorders. In our point of view, adrenal surgery should be performed by the urologist, because it's the medical speciality which knows the best this anatomical region. The objective of this review is to present the main points that the urologist may know in the management of adrenal masses. Together with the department of Endocrinology of our hospital, we describe the main studies to perform in front of adrenal mass diagnosis and the current therapeutical diagram utilized in our center (AU)


Assuntos
Humanos , Neoplasias das Glândulas Suprarrenais/cirurgia , Achados Incidentais , Cuidados Pré-Operatórios/métodos , Corticosteroides/análise
17.
Actas Urol Esp ; 34(7): 586-91, 2010 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-20540874

RESUMO

Adrenal incidentaloma's prevalence is rising because of the big volume of radiologic explorations that we daily do. No comprehensive guidelines have been published by professional societies to guide the evaluation of patients with adrenal incidentalomas. All adrenal masses should be inspected for malignancy or hypersecreting disorders. In our point of view, adrenal surgery should be performed by the urologist, because it's the medical speciality which knows the best this anatomical region. The objective of this review is to present the main points that the urologist may know in the management of adrenal masses. Together with the department of Endocrinology of our hospital, we describe the main studies to perform in front of adrenal mass diagnosis and the current therapeutical diagram utilized in our center.


Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico , Neoplasias das Glândulas Suprarrenais/terapia , Algoritmos , Humanos , Achados Incidentais , Guias de Prática Clínica como Assunto , Urologia
18.
Actas Urol Esp ; 34(5): 412-6, 2010 May.
Artigo em Espanhol | MEDLINE | ID: mdl-20470713

RESUMO

INTRODUCTION: Laparoscopic adrenalectomy is currently the gold standard in surgical management of adrenal pathology. OBJECTIVES: To analyze our results after 12 years of experience in this surgery and to compare with the main published series. MATERIAL AND METHODS: we describe retrospectively 100 adrenalectomies performed between 1997-2009. Analyzed variables: age, size, side, preoperative diagnosis, operative time, blood loss, reconversion, hospital stay and histopathologic report. We utilized Fisher test and chi square test to compare categoric data. We utilized t-Student test to compare means from independent groups with normal distribution. We considered statistical significance when p<0.05. RESULTS: Mean age was 53.1 years (+/-14.4). Mean size was 3,7 cm (+/-2.2). In 51% of cases it was the left side. Mean follow-up was 15 months (+/-11.9). Preoperative diagnosis was: functional mass (44%), pheocromocytome (17%), incedentaloma>4 cm (20%), metastasis (10%) and adrenal carcinoma (5%). Mean operative time was 145.1 min (+/-55.6). Mean hematocrite loss was 6.26 points (+/-3.3). Reconversion rate was 9.6%. 2 cases of prolonged postoperative ileus. 2 patients required transfusion. 1 patient death because of an descompensation of liver cirrhosis. 80% of complications were on right side. Mean hospital stay was 6 days (+/-5.6). In last 30 procedures we realized statistical differences with first group, in terms of operative time (119.1 min vs 171.2 min) and hospital stay (4.1 days vs 6.1) (p<0.05). CONCLUSIONS: Transperitoneal laparoscopic adrenalectomy is a surgical feasible and safe procedure in urological groups with previous laparoscopic experience. Our results are similar with the published series and confirm the efficacy, security and reproducibility of this technique.


Assuntos
Adrenalectomia/métodos , Laparoscopia , Feminino , Humanos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
19.
Actas urol. esp ; 34(5): 412-416, mayo 2010. tab
Artigo em Espanhol | IBECS | ID: ibc-81737

RESUMO

Introducción: La suprarrenalectomía laparoscópica es actualmente el gold estándar en el manejo quirúrgico de la patología suprarrenal. Objetivos: Analizar nuestros resultados tras 12 años de experiencia en esta cirugía y compararlos con las principales series publicadas. Material y métodos: Estudio descriptivo y retrospectivo. Análisis de 100 suprarrenalectomías realizadas entre junio de 1997 y junio de 2009. Se describen las siguientes variables: edad, tamaño, lateralidad, diagnóstico preoperatorio, tiempo quirúrgico, pérdida sanguínea, reconversión, complicaciones, estancia media y resultado anatomopatológico. Se utilizaron el test de Fisher y el test de chi cuadrado para comparar datos categóricos. Se utilizó el test t de Student para comparar medias de grupos independientes con distribución normal. Se consideró la significación estadística cuando p<0,05. Resultados: La edad media fue de 53,1 años (±14,4). El tamaño medio fue de 3,7cm (±2,2). En el 51% de los casos fue izquierda. La media de seguimiento fue de 15 meses (±11,9). El diagnóstico preoperatorio fue masa funcionante (44%), feocromocitoma (17%), incidentaloma mayor de 4cm (20%), metástasis (10%) y carcinoma suprarrenal (5%). El tiempo quirúrgico medio fue de 145,1 min (±55,6). El descenso medio de hematocrito fue de 6,26 puntos (±3,3). La tasa de reconversión fue del 9,6%. Hubo 2 casos de íleo postoperatorio prolongado. Dos pacientes requirieron transfusión. Uno murió en el postoperatorio por descompensación de cirrosis hepática asociada. El 80% de las complicaciones fueron en el lado derecho. La estancia media hospitalaria fue de 6 días (±5,6). En el grupo de los 30 últimos procedimientos se obtuvieron diferencias significativas en cuanto al tiempo quirúrgico (119,1 vs. 171,2min) y a la estancia media hospitalaria (4,1 vs. 6,1 días, p<0,05). Conclusiones: La suprarrenalectomía laparoscópica transperitoneal es una cirugía factible y segura en grupos con experiencia laparoscópica previa. Nuestros resultados se asemejan a las series publicadas en cuanto a la eficacia y a la morbilidad de la técnica (AU)


Introduction: Laparoscopic adrenalectomy is currently the gold standard in surgical management of adrenal pathology. Objectives: To analyze our results after 12 years of experience in this surgery and to compare with the main published series. Material & methods: we describe retrospectively 100 adrenalectomies performed between 1997–2009. Analized variables: age, size, side, preoperative diagnosis, operative time, blood loss, reconversion, hospital stay and histopathologic report. We utilized Fisher test and chi square test to compare categoric data. We utilized t-Student test to compare means from independents groups with normal distribution. We considered statistical significance when p<0.05. Results: mean age was 53,1 years (±14,4). Mean size was 3,7cm (±2,2). In 51% of cases it was the left side. Mean follow-up was 15 months (±11,9). Preoperative diagnosis was: functional mass (44%), pheocromocytome (17%), incedentaloma >4cm (20%), metastasis (10%) and adrenal carcinoma (5%). Mean operative time was 145,1min (±55,6). Mean hematocrite loss was 6,26 points (±3,3). Reconversion rate was 9,6%. 2 cases of prolonged postoperative ileus. 2 patients required transfusion. 1 patient death because of an descompensation of liver cirrhosis. 80% of complications were on right side. Mean hospital stay was 6 days (±5,6). In last 30 procedures we realized statistical differences with first group, in terms of operative time (119,1min vs 171,2min) and hospital stay (4,1 days vs 6,1) (p<0,05). Conclusions: Transperitoneal laparoscopic adrenalectomy is a surgical feasible and safe procedure in urological groups with previous laparoscopic experience. Our results are similar with the published series and confirm the efficacy, security and reproducibility of this technique (AU)


Assuntos
Humanos , Adrenalectomia/métodos , Laparoscopia/métodos , Neoplasias das Glândulas Suprarrenais/cirurgia , Estudos Retrospectivos , Complicações Pós-Operatórias/epidemiologia , Complicações Intraoperatórias/epidemiologia , Perda Sanguínea Cirúrgica/estatística & dados numéricos
20.
J Chem Phys ; 129(12): 124313, 2008 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-19045029

RESUMO

The microscopic origin and quantum effects of the low barrier hydrogen bond (LBHB) in the proton-bound ammonia dimer cation N(2)H(7) (+) were studied by means of ab initio and density-functional theory (DFT) methods. These results were analyzed in the framework of vibronic theory and compared to those obtained for the Zundel cation H(5)O(2) (+). All geometry optimizations carried out using wavefunction-based methods [Hartree-Fock, second and fourth order Moller-Plesset theory (MP2 and MP4), and quadratic configuration interaction with singles and doubles excitations (QCISD)] lead to an asymmetrical H(3)N-H(+)cdots, three dots, centeredNH(3) conformation (C(3v) symmetry) with a small energy barrier (1.26 kcalmol in MP4 and QCISD calculations) between both equivalent minima. The value of this barrier is underestimated in DFT calculations particularly at the local density approximation level where geometry optimization leads to a symmetric H(3)Ncdots, three dots, centeredH(+)cdots, three dots, centeredNH(3) structure (D(3d) point group). The instability of the symmetric D(3d) structure is shown to originate from the pseudo-Jahn-Teller mixing of the electronic (1)A(1g) ground state with five low lying excited states of A(2u) symmetry through the asymmetric alpha(2u) vibrational mode. A molecular orbital study of the pseudo-Jahn-Teller coupling has allowed us to discuss the origin of the proton displacement and the LBHB formation in terms of the polarization of the NH(3) molecules and the transfer of electronic charge between the proton and the NH(3) units (rebonding). The parallel study of the H(5)O(2) (+) cation, which presents a symmetric single-well structure, allows us to analyze why these similar molecules behave differently with respect to proton transfer. From the vibronic analysis, a unified view of the Rudle-Pimentel three-center four-electron and charge transfer models of LBHBs is given. Finally, the large difference in the N-N distance in the D(3d) and C(3v) configurations of N(2)H(7) (+) indicates a large anharmonic coupling between alpha(2u)-alpha(1g) modes along the proton-transfer dynamics. This issue was explored by solving numerically the vibrational Schrodinger equation corresponding to the bidimensional E[Q(alpha(2u)),Q(alpha(1g))] energy surface calculated at the MP46-311++G(**) level of theory.


Assuntos
Amônia/química , Dimerização , Cátions/química , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Movimento (Física) , Prótons , Teoria Quântica , Vibração , Água/química
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