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1.
BJS Open ; 8(4)2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38987232

RESUMEN

BACKGROUND: Inguinal lymph node dissection plays an important role in the management of melanoma, penile and vulval cancer. Inguinal lymph node dissection is associated with various intraoperative and postoperative complications with significant heterogeneity in classification and reporting. This lack of standardization challenges efforts to study and report inguinal lymph node dissection outcomes. The aim of this study was to devise a system to standardize the classification and reporting of inguinal lymph node dissection perioperative complications by creating a worldwide collaborative, the complications and adverse events in lymphadenectomy of the inguinal area (CALI) group. METHODS: A modified 3-round Delphi consensus approach surveyed a worldwide group of experts in inguinal lymph node dissection for melanoma, penile and vulval cancer. The group of experts included general surgeons, urologists and oncologists (gynaecological and surgical). The survey assessed expert agreement on inguinal lymph node dissection perioperative complications. Panel interrater agreement and consistency were assessed as the overall percentage agreement and Cronbach's α. RESULTS: Forty-seven experienced consultants were enrolled: 26 (55.3%) urologists, 11 (23.4%) surgical oncologists, 6 (12.8%) general surgeons and 4 (8.5%) gynaecology oncologists. Based on their expertise, 31 (66%), 10 (21.3%) and 22 (46.8%) of the participants treat penile cancer, vulval cancer and melanoma using inguinal lymph node dissection respectively; 89.4% (42 of 47) agreed with the definitions and inclusion as part of the inguinal lymph node dissection intraoperative complication group, while 93.6% (44 of 47) agreed that postoperative complications should be subclassified into five macrocategories. Unanimous agreement (100%, 37 of 37) was achieved with the final standardized classification system for reporting inguinal lymph node dissection complications in melanoma, vulval cancer and penile cancer. CONCLUSION: The complications and adverse events in lymphadenectomy of the inguinal area classification system has been developed as a tool to standardize the assessment and reporting of complications during inguinal lymph node dissection for the treatment of melanoma, vulval and penile cancer.


Asunto(s)
Consenso , Técnica Delphi , Conducto Inguinal , Escisión del Ganglio Linfático , Melanoma , Neoplasias del Pene , Complicaciones Posoperatorias , Neoplasias de la Vulva , Humanos , Escisión del Ganglio Linfático/efectos adversos , Escisión del Ganglio Linfático/métodos , Femenino , Masculino , Neoplasias del Pene/cirugía , Neoplasias del Pene/patología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/epidemiología , Neoplasias de la Vulva/cirugía , Neoplasias de la Vulva/patología , Melanoma/cirugía , Melanoma/patología , Conducto Inguinal/cirugía , Encuestas y Cuestionarios
2.
J Org Chem ; 78(4): 1343-53, 2013 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-23373989

RESUMEN

Notwithstanding its half-life of 70 years at 25 °C, the spontaneous hydrolysis of the anion of di-2-pyridyl phosphate (DPP) is thousands of times faster (ca. 3000 at 100 °C, over 10000-fold at 25 °C) than expected for a diester with leaving groups of pK(a) 9.09. The kinetic parameters do not permit a conclusive choice between five possible mechanisms considered, but the combination of kinetics and calculational evidence supports a single-step, concerted, S(N)2(P) mechanism involving the attack of solvent water on phosphorus assisted by intramolecular catalysis by a (weakly basic) pyridine nitrogen acting as a general base. Catalysis is relatively efficient for this mechanism, with an estimated effective molarity (EM) of the general base of >15 M, consistent with the absence of catalysis by typical buffers. Further new results confirm that varying the nonleaving group has minimal effect on the rate of spontaneous diester hydrolysis, in striking contrast to the major effect on the corresponding reaction of triesters: though protonation of one nitrogen of DPP(-) increases the rate of hydrolysis by 6 orders of magnitude, in line with expectation.


Asunto(s)
Organofosfatos/química , Piridinas/química , Catálisis , Ésteres , Concentración de Iones de Hidrógeno , Hidrólisis , Cinética , Estructura Molecular , Temperatura , Agua
3.
J Vis Exp ; (194)2023 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-37184250

RESUMEN

Urethral reconstruction is an important area of expertise for urologists. The buccal mucosa is considered the best option when urethral grafting is necessary, although in some cases, it is inappropriate or needs to be optimized to repair a given stricture. Therefore, developing innovative procedures and evaluating their putative success in experimental models is crucial to fit the clinical need. With this goal, this study describes a protocol in which urethral stricture was induced by electrocautery in Wistar rats. Urethral reconstruction was performed 1 week later with a buccal mucosa graft, harvested from the lower lip, and placed in a ventral onlay fashion. A retrograde urethrogram showed a significant improvement in urethral diameter after urethroplasty compared to the respective value after stricture induction. Additionally, the graft placement was assessed by blood perfusion analysis using laser Doppler. As expected, a dark blue area corresponded to the non-vascularized buccal mucosa graft. This procedure can successfully simulate the normal pathophysiological process of urethral injury and tissue modulation, as well as urethral reconstruction using a buccal mucosa graft in a reproducible manner, and serve as the basis for future research based on tissue engineering or urethral grafts.


Asunto(s)
Mucosa Bucal , Uretra , Estrechez Uretral , Procedimientos Quirúrgicos Urológicos Masculinos , Animales , Masculino , Ratas , Mucosa Bucal/cirugía , Ratas Wistar , Resultado del Tratamiento , Estrechez Uretral/diagnóstico por imagen , Estrechez Uretral/cirugía , Procedimientos Quirúrgicos Urológicos Masculinos/efectos adversos , Procedimientos Quirúrgicos Urológicos Masculinos/métodos , Uretra/irrigación sanguínea , Uretra/diagnóstico por imagen , Uretra/cirugía , Flujometría por Láser-Doppler , Imagen de Perfusión , Modelos Animales de Enfermedad , Electrocoagulación
4.
Front Hum Neurosci ; 16: 941981, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36118977

RESUMEN

Introduction: Transcranial magnetic stimulation (TMS) is a consolidated procedure for the treatment of depression, with several meta-analyses demonstrating its efficacy. Theta-burst stimulation (TBS) is a modification of TMS with similar efficacy and shorter session duration. The geriatric population has many comorbidities and a high prevalence of depression, but few clinical trials are conducted specifically for this age group. TBS could be an option in this population, offering the advantages of few side effects and no pharmacological interactions. Therefore, our aim is to investigate the efficacy of TBS in geriatric depression. Clinical trial registration: [https://clinicaltrials.gov/ct2/], identifier [NCT04842929].

5.
Chemistry ; 17(52): 14996-5004, 2011 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-22106028

RESUMEN

The high rate of spontaneous hydrolysis of tris-2-pyridyl phosphate (TPP) is explained by the activating effects of the non-leaving ("spectator") groups on P-OAr cleavage, and not by intramolecular catalysis. Previous work on phosphate-transfer reactions has concentrated on the contributions to reactivity of the nucleophile and the leaving group, but our results make clear that the effects of the non-leaving groups on phosphorus can be equally significant. Rate measurements for three series of phosphate triesters showed that sensitivities to the non-leaving groups are substantial for spontaneous hydrolysis reactions, although significantly smaller for reactions with good nucleophiles. There are clear differences between triaryl and dialkyl aryl triesters in sensitivities to leaving and non-leaving groups with the more reactive triaryl systems showing lower values for both ß(LG) and ß(NLG). Intramolecular catalysis of the hydrolysis of TPP by the neighbouring pyridine nitrogens is insignificant, primarily because of their low basicity.


Asunto(s)
Organofosfatos/química , Piridinas/química , Catálisis , Concentración de Iones de Hidrógeno , Hidrólisis , Cinética , Estructura Molecular
6.
J Org Chem ; 76(19): 8003-8, 2011 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-21861472

RESUMEN

The phosphorylation of imidazole by two activated phosphate diesters and a triester gives phosphorylimidazole derivatives that are stable enough in aqueous solution to be observed and identified by ESI-MS/MS and NMR. Half-lives ranging from hours to days (in the case of the monoethyl ester) show that it is possible to design molecules with variable half-lives with potential to be used for biological intervention experiments as possible inhibitors of biosignaling processes or as haptens for the generation of antibodies.


Asunto(s)
Imidazoles/química , Imidazoles/metabolismo , Transducción de Señal , Diseño de Fármacos , Ésteres , Cinética , Espectroscopía de Resonancia Magnética , Espectrometría de Masa por Ionización de Electrospray
7.
J Environ Monit ; 12(1): 355-60, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20082032

RESUMEN

Dissolved oxygen (DO) is one of the most important environmental variables of water quality, especially for marine life. Consequently, oxygen is one of the Chemical Quality Elements required for the implementation of European Union Water Framework Directive. This study uses the example of the Ria Formosa, a meso-tidal lagoon on the south coast of Portugal to demonstrate how monitoring of water quality for coastal waters must be well designed to identify symptoms of episodic hypoxia. New data from the western end of the Ria Formosa were compared to values in a database of historical data and in the published literature to identify long-term trends. The dissolved oxygen concentration values in the database and in the literature were generally higher than those found in this study, where episodic hypoxia was observed during the summer. Analysis of the database showed that the discrepancy was probably related with the time and the sites where the samples had been collected, rather than a long-term trend. The most problematic situations were within the inner lagoon near the city of Faro, where episodic hypoxia (<2 mg dm(-3) DO) occurred regularly in the early morning. These results emphasise the need for a balanced sampling strategy for oxygen monitoring which includes all periods of the day and night, as well as a representative range of sites throughout the lagoon. Such a strategy would provide adequate data to apply management measures to reduce the risk of more persistent hypoxia that would impact on the ecological, economic and leisure uses of this important natural resource.


Asunto(s)
Ecosistema , Monitoreo del Ambiente , Geografía , Oxígeno/análisis , Agua de Mar/química , Hipoxia/metabolismo , Hipoxia/patología , Oxígeno/metabolismo , Portugal , Control de Calidad , Estaciones del Año
8.
Chemistry ; 15(34): 8475-8479, 2009 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-19621399

RESUMEN

We have identified the first highly efficient intramolecular general base catalysis (IGBC) of a hydrolysis reaction, in a system where two general bases are available to assist the attack of the same nucleophilic water molecule. The suggested mechanism, available uniquely to a phosphate triester model, is readily available in enzyme active sites, and the results suggest a possible solution to the long-unsolved question of how enzymes are able to activate a water molecule to be a highly effective nucleophile.


Asunto(s)
Fosfatos/química , Agua/química , Catálisis , Cristalografía por Rayos X , Activación Enzimática , Ésteres , Hidrólisis , Cinética , Modelos Moleculares , Estereoisomerismo , Termodinámica
9.
Rev Port Cir Cardiotorac Vasc ; 15(3): 163-6, 2008.
Artículo en Portugués | MEDLINE | ID: mdl-19116682

RESUMEN

The authors report the clinical case of a 34 years old male, with a germ cell tumor of the testis, who developed large retroperitoneal metastasis, with compression and later on invasion of the inferior vena cava. The patient underwent chemotherapy followed by resection of the original tumor and of the retroperitoneal metastasis and the vena cava was replaced by a vascular prosthesis. The post operative course was uneventful and one year later he was found in excellent condition. The rarity of the situation as well as of its surgical management justifies the presentation and the discussion of the case, based on the most recent data of the literature dedicated to the topic.


Asunto(s)
Neoplasias de Células Germinales y Embrionarias/patología , Neoplasias de Células Germinales y Embrionarias/cirugía , Neoplasias Testiculares/patología , Neoplasias Testiculares/cirugía , Neoplasias Vasculares/patología , Neoplasias Vasculares/cirugía , Vena Cava Inferior , Adulto , Humanos , Masculino , Invasividad Neoplásica
10.
Am J Surg Pathol ; 34(3): 371-6, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20139762

RESUMEN

In this report, we present the clinicopathologic features of 27 cases of the lipid cell variant of urothelial bladder carcinoma. This is a rare variant of bladder cancer recognized by the current WHO classification of urologic tumors. The lipid cell component varied from 10% to 50% of the tumor specimen; in 11 cases the lipid cell component composed greater than 30% of the tumor. The architectural pattern of the tumor varied from solid expansile to infiltrative nests. The large epithelial tumor cells had an eccentrically placed nucleus and abundant vacuolated cytoplasm resembling signetring lipoblasts. Mucin stains were negative in all the cases. Typical features of high grade conventional urothelial carcinoma were present in all the cases with micropapillary or plasmacytoid carcinoma in 2 and 1 cases, respectively; extensive squamous or glandular differentiation was present in 2 additional cases. Most neoplastic cells had nuclei of intermediate nuclear grade with occasional nuclear pleomorphism. Immunohistochemical staining showed that the lipid cell component was positive for cytokeratins 7, 20, CAM 5.2, high molecular weight (34ssE12) and AE1/AE3, epithelial membrane antigen, and thrombomodulin; vimentin and S100 protein were negative. The loss of heterozygosity (LOH) analysis was done on 8 cases using 4 polymorphic microsatellite markers (D9S171, D9S177, IFNA, and TP 53); LOH at least in 1 marker was present in 6 cases. The LOH results were the same for lipid variant and conventional urothelial carcinoma. Pathologic stage was Ta (n=1), T1 (=2), T2, at least (n=7), T3a (n=4), T3b (n=8), and T4a (n=5). Electron microcopy analysis based on 2 cases supported lipid content in tumor cells. Follow-up information was available in all the cases, ranging from 6 to 58 months (mean, 28 mo). Sixteen of the patients died of disease at 16 to 58 months (mean, 33 mo) and 8 patients were alive with disease at 8 to 25 months (mean, 22 mo). Another 3 patients died of other causes at 6 to 15 months (mean, 10 mo). In summary, lipid cell urothelial bladder carcinoma is typically associated with advanced stage high-grade urothelial carcinoma, in which the prognosis is poor and clonally related to the concurrent conventional urothelial carcinoma. In limited samples, it may be misdiagnosed as liposarcoma, sarcomatoid carcinoma (carcinosarcoma), or signetring cell carcinoma. Morphologic distinction from other malignant neoplasms with lipid cell phenotype is critical for its clinical management.


Asunto(s)
Carcinoma/genética , Lípidos/análisis , Pérdida de Heterocigocidad , Repeticiones de Microsatélite , Neoplasias de la Vejiga Urinaria/genética , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/análisis , Carcinoma/química , Carcinoma/mortalidad , Carcinoma/patología , Carcinoma/terapia , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Factores de Tiempo , Resultado del Tratamiento , Neoplasias de la Vejiga Urinaria/química , Neoplasias de la Vejiga Urinaria/mortalidad , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/terapia , Urotelio/química , Urotelio/patología
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