Derivação hepaticojejunal sem sutura: uma alternativa para reconstituição da via biliar

A lesão das vias biliares foi observada em dois pacientes submetidos à colecistectomia videolaparoscópica e convencional. Para reconstituição da via biliar foi aplicada a técnica hepaticojejunostomia em Y-de-Roux com a introdução dao segmento proximal do ducto hepático comum, apoiada por um catéter perdido na luz da alça exclusa, sem sutura. O grau das lesões segundo a classificação de Bismuth tomou a técnica exeqüível. No período de nov/94 a fev/97 os casos evoluíram clinicamente assintomáticos e com exames laboratoriais dentro dos padrões de normalidade. O controle ultra-sonográfico demonstra a presença do catéter simulando o colédoco. A boa evolução dos casos não nos autoriza a conclusões definitivas. A facilidade técnica e a baixa morbidade no pós-operatório nos motivaram a escrever este artigo.

Tratamento cirúrgico das estenoses da via biliar

OBJETIVO: As estenoses benignas da via biliar (EBVB) decorrem de lesões iatrogênicas em 95% casos. Embora pouco freqüentes seu prognóstico é sombrio, e a prevenção é o melhor tratamento. O objetivo deste trabalho é estudar a conduta cirúrgica nas EBVB e seus resultados. MÉTODO: Foram analisados retrospectivamente, 11 pacientes submetidos à correção de EBVB no Hospital Universitário Regional do Norte do Paraná (HURNP) no período de Julho/1992 a Dezembro/2001. RESULTADOS: Nove pacientes eram do sexo feminino e dois do masculino,com média de idade de 43,71 (± 17,05) anos. A cirurgia que originou a lesão foi colecistectomia aberta em 81,8% dos pacientes e por laparoscopia em 18,2%. Os sinais e sintomas mais freqüentes foram icterícia (64,3%), dor (64,3%), e febre (21,4%). O diagnóstico foi confirmado por colangiopancreatografia retrógrada endoscópica (CPRE) em 90,9% dos casos e por colangiografia transparieto- hepática (CTPH) em 9,1%. Segundo os critérios de Bismuth lesões do tipo I ocorreram em 18,2% dos casos, tipo II em 45,4%, tipo III em 18,2% e tipo IV em 18,2%. O tratamento cirúrgico para as EBVB foi anastomose colédoco-duodenal, anastomose hepático-jejunal em Y de Roux , anastomose hepático-jejunal à Hepp- Couinaud e anastomose hepático-jejunal com enxertia de mucosa (Smith), para as lesões tipo I,II,III e IV, respectivamente. Seis (54,55%) pacientes apresentaram complicações pós-operatórias , e dois (18,2%) evoluíram para óbito CONCLUSÕES: As correções cirúrgicas das EBVB apresentam altos índices de complicações e devem ser realizadas em centros especializados. Em geral estas estenoses decorrem de lesões iatrogênicas durante colecistectomias.

A influência do tempo de referencia no tratamento das lesões iatrogênicas da via biliar

OBJETIVO: Avaliar o prognóstico dos pacientes com lesão iatrogênica da via biliar (LIVB) em relação ao tempo de referencia (TR) para a unidade de transplante hepático (TH). MÉTODOS: Foram revisados 51 prontuários de pacientes que sofreram algum tipo de LIVB durante a colecistectomia e que foram encaminhados para a unidade de TH no Hospital Geral de Bonsucesso (HGB). As lesões foram agrupadas de acordo com a classificação de Bismuth. Além da colecistectomia (momento da lesão), também avaliamos o TR e o desfecho. RESULTADOS: Dentre os 51 pacientes estudados encontramos 17 homens e 34 mulheres com uma média de idade de 42,7 anos. Vinte e dois pacientes (43,1%) tinham uma lesão do tipo II; 13 (25,5 %) do tipo III; 10 (19,6 %) do tipo I, 5 (9,8 %) do tipo IV; e apenas um (2 %) do tipo V. Quarenta pacientes foram operados, sendo que três não retornaram para revisão médica e portanto, 37 foram avaliados em relação ao desfecho. Dentre esses, 25 pacientes (67,6 %) tiveram resultados excelentes ou bons com TR médio de 11,5 meses (intervalo: 2-48 meses) e 47,2 meses (intervalo: 3-180 meses) respectivamente. Os 12 pacientes (32,4 %) com resultados ruins tiveram um TR médio de 65,9 meses (intervalo: 3-264 meses), que foi significativamente maior do que o grupo com resultados excelentes ou bons (p=0,004). Sete pacientes foram listadas para fila de TH, porém apenas dois foram realizados. O TR desses sete pacientes foi significativamente mais elevado (p=0,04) do que o daqueles pacientes não listados. Sete pacientes morreram, dos quais seis foram causados por complicações hepáticas. CONCLUSÃO: O TR influenciou significativamente no prognóstico dos pacientes da nossa amostra.

Multiple forms of cotyledonary b-galactosidases from Vigna unguiculata quiescent seeds

Cotyledonary b-galactosidases were isolated and partially purified from Pitiúba cowpea (Vigna unguiculata (L.) Walp.) quiescent seeds. The purification steps consisted of precipitation of the crude extract with ammonium sulphate in the range of 20-60% saturation, acid precipitation, DEAE-Sephadex ion-exchange chromatography and Lactosyl-Sepharose affinity chromatography. This purification process gave rise to three b-galactosidases-rich fractions: b-gal I, b-gal II and b-gal III, which were purified about 5, 509, and 62 fold, respectively. They reached maximal enzyme activity at different pH ranges: 3.5-4.5 for b-gal I, 3.0-3.5 for b-gal II, and 3.0-4.0 for b-gal III. Their maximal activities were reached when the temperature of the assay medium was 60° C, and preincubation of the enzymes at different temperatures has shown that they were heat-stable up to 50° C. There were no significant differences among the partially purified enzymes as far as their response to the different effectors tested, except for Mn2+ and EDTA, which affected differently b-gal I, b-gal II, and b-gal III. They were slightly affected by Mg2+, Ca2+, Zn2+, Co2+, tartarate, molybdate, glucose, and lactose, strongly inhibited by Cu2+ and galactose, and inactivated by Hg2+. These chemical and physical properties are similar to the ones found for other plant b-galactosidases. Although through this process of purification three isoforms of this enzyme were obtained, isoelectric focusing in polyacrylamide slab gel of these enzyme-proteins suggest that cotyledons of Pitiúba cowpea quiescent seeds possess four isoforms of b-galactosidases.

Efficacy of a quadruple therapy regimen for Helicobacter pylori eradication after partial gastrectomy

We aimed to evaluate the effectiveness and safety of bismuth-containing quadruple therapy plus postural change after dosing for Helicobacter pylori eradication in gastrectomized patients. We compared 76 gastric stump patients with H. pylori infection (GS group) with 50 non-gastrectomized H. pylori-positive patients who met the treatment indication (controls). The GS group was divided into GS group 1 and GS group 2. All groups were administered bismuth potassium citrate (220 mg), esomeprazole (20 mg), amoxicillin (1.0 g), and furazolidone (100 mg) twice daily for 14 days. GS group 1 maintained a left lateral horizontal position for 30 min after dosing. H. pylori was detected using rapid urease testing and histologic examination of gastric mucosa before and 3 months after therapy. Mucosal histologic manifestations were evaluated using visual analog scales of the updated Sydney System. GS group 1 had a higher prevalence of eradication than the GS group 2 (intention-to-treat [ITT]: P=0.025; per-protocol [PP]: P=0.030), and the control group had a similar prevalence. GS group 2 had a lower prevalence of eradication than controls (ITT: P=0.006; PP: P=0.626). Scores for chronic inflammation and activity declined significantly (P<0.001) 3 months after treatment, whereas those for atrophy and intestinal metaplasia showed no significant change. Prevalence of adverse reactions was similar among groups during therapy (P=0.939). A bismuth-containing quadruple therapy regimen plus postural change after dosing appears to be a relatively safe, effective, economical, and practical method for H. pylori eradication in gastrectomized patients.

Synthèse d’un inhibiteur de la rénine, l’aliskiren et développement de méthodes catalytiques d’alkylation asymétrique

Une nouvelle approche pour la synthèse de l’aliskiren, un puissant inhibiteur de la rénine pour le traitement de l’hypertension chez l’homme, a été développée. De cette approche, des étapes clés tels qu’une allylation avec un des catalyseurs de MacMillan, une cyclisation par métathèse (RCM) pour la préparation d’une lactone à neuf membres et une séquence de réactions d’aziridination diastéréosélective/réarrangement de cycle par une catalyse acide donnant un produit aminohydroxylé ont permis de compléter la synthèse de l’aliskiren en 11 étapes. Durant l’élaboration de la séquence de réactions pour la préparation de l’aliksiren, il a été noté que la lactone à neuf membres avait une facilité à se réarranger via des intermédiaires quinonoïdaux et les produits issus de cette tendance ont été analysés. De plus, une étude sur la réaction de RCM, donnant la lactone à neuf membres, a montré une dépendance envers la nature diastéréomérique du substrat de départ. Une méthodologie d’alpha-allylation asymétrique de cétones catalysée au palladium, tirant avantage d’un ligand chiral PHOX, a été explorée et utilisée en vue de la synthèse de l’aliskiren. De cette méthode, une étude pour la synthèse de produits alpha-allylcétones acycliques a été démontrée et un effet d’additif sur la sélectivité et la vitesse de réaction a été découvert. De plus, la production d’un intermédiaire avancé d’un produit d’intérêts a été accomplie et la nature de la contribution de l’additif a été investiguée. Les produits obtenus depuis la méthodologie d’allylation catalysée au palladium et la formation d’intermédiaire cationique des certains dérivés de la synthèse de l’aliskiren ont inspirés une nouvelle approche faisant appel à des techniques d’alkylation en catalyse acide pour la formation de produits diaryliques. Il a été trouvé que le catalyseur de chlorure d’or(III) et de triflate de bismuth(III) étaient particulièrement efficaces, démontrant une différence de cinétique pour la réactivité d’un mélange diastéréoisomériques d’alcools alpha-substitués de départ.

Activation of Progesterone Receptor by ATP

Progesterone-receptor complex from freshly prepared hen oviduct cytosol acquired the ability to bind to isolated nuclei, DNA-cellulose and ATP-Sepharose when incubated with 5-10 mM ATP at 4°C. The extent of this ATP-dependent activation was higher when compared with heat-activation achieved by warming the progesterone- receptor complex at 23 °C. The transformation of progesterone-receptor complex which occurred in a time-dependent manner was only partially dependent on hormone presence. The ATP effect was selective in causing this transformation whereas ADP, AMP and cAMP failed to show any such effect. The non-hydrolizable analogs of ATP, adenosine 5'-[a,/3-methylene]triphosphate and adenosine 5-[/l,y-imido]triphosphate were also found to be ineffective. Presence of 10 mM sodium molybdate blocked both the ATP and the heat-activation of progesterone-receptor complex. Mn" or Mg` had no detectable effect on the receptor activation but the presence of Ca" increased the extent of ATP-activation slightly. EDTA presence (> 5 mM) decreased the extent of receptor activation by about 40 % and was, therefore, not included in the buffers used for activation studies. Divalent cations were also ineffective when tested in the presence of 1- 5 mM EDTA. The properties of progesterone-receptor complex remained intact under the above conditions when analyzed for steroid-binding specificity and Scatchard analysis. However, the ATP-activated progesterone-receptor complex lost the ability to aggregate when tested on low-salt sucrose gradients. ATP was equally effective in activating the rat-uterine estradiol-receptor complex at 4 "C and influenced the transformation of 4-S receptor form into a 5-S form when analyzed on sucrose gradients containing 0.3 M KCI. The presence of ATP also increased the rate of activation of progesterone-receptor complex at 23 °C. These findings suggest a role for ATP in receptor function and offer a convenient method of studying the process of receptor activation at low temperature and mild assay conditions.

Tailoring the microwave dielectric properties of BaRE2Ti4O12 and BaRE2Ti5O14 ceramics bycompositional variations

Ceramic dielectric resonators in the BaO-RE2O3-TiO2 (RE=rare earth) system have been prepared by the conventional solid state ceramic route. The dielectric properties have been tailored by substitution of different rare earth oxides and by bismuth oxide addition. The dielectric constants increased with Bi addition whereas the Q decreased. The temperature coeffecient of the resonant frequency improved with bismuth addition.

Tailoring the Microwave Dielectric Properties of BaRE2Ti4012 and BaRE2Ti5014 Ceramics by Compositional Variations

Ceramic dielectric resonators in the BaO-RE2O3-TiO2 (RE = rare earth) system have been prepared by the conventional solid state ceramic route. The dielectric properties have been tailored by substitution of different rare earth oxides and by bismuth oxide addition. The dielectric constants increased with Bi addition whereas the 0 decreased. The temperature coefficient of the resonant frequency improved with bismuth addition

Measurement of laser ablation threshold on doped BiSrCaCuO high temperature superconductors by the pulsed photothermal deflection technique

Laser‐induced damage and ablation thresholds of bulk superconducting samples of Bi2(SrCa)xCu3Oy(x=2, 2.2, 2.6, 2.8, 3) and Bi1.6 (Pb)xSr2Ca2Cu3 Oy (x=0, 0.1, 0.2, 0.3, 0.4) for irradiation with a 1.06 μm beam from a Nd‐YAG laser have been determined as a function of x by the pulsed photothermal deflection technique. The threshold values of power density for ablation as well as damage are found to increase with increasing values of x in both systems while in the Pb‐doped system the threshold values decrease above a specific value of x, coinciding with the point at which the Tc also begins to fall.  

Theory of laser-induced ultrafast structural changes in solids

The present thesis is a contribution to the study of laser-solid interaction. Despite the numerous applications resulting from the recent use of laser technology, there is still a lack of satisfactory answers to theoretical questions regarding the mechanism leading to the structural changes induced by femtosecond lasers in materials. We provide here theoretical approaches for the description of the structural response of different solids (cerium, samarium sulfide, bismuth and germanium) to femtosecond laser excitation. Particular interest is given to the description of the effects of the laser pulse on the electronic systems and changes of the potential energy surface for the ions. Although the general approach of laser-excited solids remains the same, the potential energy surface which drives the structural changes is calculated with different theoretical models for each material. This is due to the difference of the electronic properties of the studied systems. We use the Falicov model combined with an hydrodynamic method to study photoinduced phase changes in cerium. The local density approximation (LDA) together with the Hubbard-type Hamiltonian (LDA+U) in the framework of density functional theory (DFT) is used to describe the structural properties of samarium sulfide. We parametrize the time-dependent potential energy surface (calculated using DFT+ LDA) of bismuth on which we perform quantum dynamical simulations to study the experimentally observed amplitude collapse and revival of coherent $A_{1g}$ phonons. On the basis of a time-dependent potential energy surface calculated from a non-orthogonal tight binding Hamiltonian, we perform molecular dynamics simulation to analyze the time evolution (coherent phonons, ultrafast nonthermal melting) of germanium under laser excitation. The thermodynamic equilibrium properties of germanium are also reported. With the obtained results we are able to give many clarifications and interpretations of experimental results and also make predictions.

Factores asociados a diabetes de nuevo inicio en pacientes postrasplante hepático, un estudio de casos y controles

INTRODUCCIÓN: El trasplante hepático ha permitido mejorar la calidad de vida y la supervivencia de los pacientes con cirrosis, se ha identificado un gran espectro de complicaciones crónicas, dentro de las cuales la Diabetes Mellitus de nuevo inicio posterior al trasplante (DMNPT) hace parte y genera un impacto significativo con relación a morbimortalidad. Nuestro objetivo fue determinar los factores asociados para el desarrollo de DMNPT. METODOLOGÍA: Se llevó a cabo un estudio de casos y controles sobre una cohorte histórica donde se revisaron pacientes colombianos postrasplante hepático y se evaluaron factores clínicos asociados con el inicio de DMNPT. RESULTADOS: Se encontró que la incidencia de DMNPT en nuestra población fue de 14.3% (32/224), con una mediana de aparición desde el procedimiento hasta el diagnóstico de 10 meses (IQR 1 - 40). De los 32 casos el 62.5% (20/32) fueron hombres, con una mediana de edad de 55.5 años. La presencia de encefalopatía (ORA 3,55 IC 95% 1.07-8.2), intolerancia a los carbohidratos (ORA 2,97 IC 95% 1.35-9.32) y el tiempo de isquemia (ORA 1.005 IC 95% 1.001 – 1.01) fueron significativamente asociados con el desenlace, en contraste la etiología autoinmune de la cirrosis se comportó como un factor protector (OR 0.34 IC 95% 0.12-091). CONCLUSIÓN: A pesar de las limitaciones del estudio, hay consistencia con resultados previos con respecto a la asociación entre estas variables independientes y el desarrollo de DMNPT, características que se deben tener en cuenta en el seguimiento de este grupo de pacientes estableciendo estrategias de seguimiento rigurosas y terapéuticas tempranas con miras a disminuir el riesgo de progresión a DM.

Use of 16S rRNA-targeted oligonucleotide probes to investigate function and phylogeny of sulphate-reducing bacteria and methanogenic archaea in a UK estuary

Sulphate-reducing bacteria (SRB) and methanogenic archaea (MA) are important anaerobic terminal oxidisers of organic matter. However, we have little knowledge about the distribution and types of SRB and MA in the environment or the functional role they play in situ. Here we have utilised sediment slurry microcosms amended with ecologically significant substrates, including acetate and hydrogen, and specific functional inhibitors, to identify the important SRB and MA groups in two contrasting sites on a UK estuary. Substrate and inhibitor additions had significant effects on methane production and on acetate and sulphate consumption in the slurries. By using specific 16S-targeted oligonucleotide probes we were able to link specific SRB and MA groups to the use of the added substrates. Acetate consumption in the freshwater-dominated sediments was mediated by Methanosarcinales under low-sulphate conditions and Desulfobacter under the high-sulphate conditions that simulated a tidal incursion. In the marine-dominated sediments, acetate consumption was linked to Desulfobacter. Addition of trimethylamine, a non-competitive substrate for methanogenesis, led to a large increase in Methanosarcinales signal in marine slurries. Desulfobulbus was linked to non-sulphate-dependent H-2 consumption in the freshwater sediments. The addition of sulphate to freshwater sediments inhibited methane production and reduced signal from probes targeted to Methanosarcinales and Methanomicrobiales, while the addition of molybdate to marine sediments inhibited Desulfobulbus and Desulfobacterium. These data complement our understanding of the ecophysiology of the organisms detected and make a firm connection between the capabilities of species, as observed in the laboratory, to their roles in the environment. (C) 2003 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.

Solid supported micellar analysis: some syntheses and characterisations

A synthetic method for chemically tethering organic based surfactant molecules and fluorous surfactant molecules onto a high surface and pore volume silica has been developed. It is shown that heterogenisation of a simple water-soluble ions (i.e. molybdate ion and Co2+) can be accomplished onto these composite materials. They display an excellent activity and selectivity for oxidation of organic molecules in bulk organic solvent or in supercritical CO2. Characterisations indicate that catalysis occurs within the surface supported surfactant assemblies (chemically tethered reversed micelles) in the porous silica structure. (C) 2003 Elsevier B.V. All rights reserved.

Synthesis and reactions of [Et3NH]4[Mo8O6]: X-ray crystal structure of [Et3NH]3[NaMo8O26]

[Et3NH]4[Mo8O26] (1) was prepared by reacting triethylamine with either molybdenum trioxide dihydrate or with a solution of ammonium molybdate in aqueous HCl. An aqueous solution of complex 1 reacted with an excess of sodium chloride to give a mixture of [Et3NH]3[NaMo8O26] (2) and [Et3NH]2[Mo6O19] (3). Complex 2 was also formed on reacting sodium molybdate with triethylamine in aqueous HCl. In the reaction of 1 with potassium chloride the nature of the product obtained was critically dependent upon reaction time. After a 5.5 h reflux period a mixture of [Et3NH]3[KMo8O26] (4) and 3 was obtained, whereas upon prolonged reflux (24 h) only K4Mo8O26 · H2O (5) was precipitated. The X-ray crystal structure of 2 shows it to be polymeric, with each Na+ ion sandwiched between two β[Mo8O26]4− ions. Four oxygen atoms on one face of each β[Mo8O26]4− ion are coordinated to a Na+ ion, and four oxygens from the opposite face are bonded to the next Na+ ion in the polymer chain. This produces a zig-zag arrangement of Na+ ions throughout the molecular structure. Spectral, conductivity and voltammetry data are given.