Avaliação dos insulinomas pela ultra-sonografia intra-operatória: estado atual do tema

Os autores fazem uma revisão da literatura sobre a utilização da ultra-sonografia intra-operatória para a avaliação dos insulinomas pancreáticos. São referidos os resultados da ultra-sonografia intra-operatória, ultra-sonografia e tomografia computadorizada realizadas no pré-operatório, e os resultados da inspeção e palpação do pâncreas realizadas durante procedimentos cirúrgicos referidos na literatura.

A Randomized, Placebo-controlled Trial of Preemptive Antifungal Therapy for the Prevention of Invasive Candidiasis Following Gastrointestinal Surgery for Intra-abdominal Infections.

BACKGROUND: Patients undergoing emergency gastrointestinal surgery for intra-abdominal infection are at risk of invasive candidiasis (IC) and candidates for preemptive antifungal therapy. METHODS: This exploratory, randomized, double-blind, placebo-controlled trial assessed a preemptive antifungal approach with micafungin (100 mg/d) in intensive care unit patients requiring surgery for intra-abdominal infection. Coprimary efficacy variables were the incidence of IC and the time from baseline to first IC in the full analysis set; an independent data review board confirmed IC. An exploratory biomarker analysis was performed using logistic regression. RESULTS: The full analysis set comprised 124 placebo- and 117 micafungin-treated patients. The incidence of IC was 8.9% for placebo and 11.1% for micafungin (difference, 2.24%; [95% confidence interval, -5.52 to 10.20]). There was no difference between the arms in median time to IC. The estimated odds ratio showed that patients with a positive (1,3)-β-d-glucan (ßDG) result were 3.66 (95% confidence interval, 1.01-13.29) times more likely to have confirmed IC than those with a negative result. CONCLUSIONS: This study was unable to provide evidence that preemptive administration of an echinocandin was effective in preventing IC in high-risk surgical intensive care unit patients with intra-abdominal infections. This may have been because the drug was administered too late to prevent IC coupled with an overall low number of IC events. It does provide some support for using ßDG to identify patients at high risk of IC. CLINICAL TRIALS REGISTRATION: NCT01122368.

Determinants of male fitness: disentangling intra- and inter-sexual selection.

Both intra- and inter-sexual selection may crucially determine a male's fitness. Their interplay, which has rarely been experimentally investigated, determines a male's optimal reproductive strategy and thus is of fundamental importance to the understanding of a male's behaviour. Here we investigated the relative importance of intra- and inter-sexual selection for male fitness in the common lizard. We investigated which male traits predict a male's access to reproduction allowing for both selective pressures and comparing it with a staged mating experiment excluding all types of intra-sexual selection. We found that qualitatively better males were more likely to reproduce and that sexual selection was two times stronger when allowing for both selective pressures, suggesting that inter- and intra-sexual selection determines male fitness and confirming the existence of multi-factorial sexual selection. Consequently, to optimize fitness, males should trade their investment between the traits, which are important for inter- and intra-sexual selection.

Altérations dans le cordon ombilical de nouveau-nés avec une restriction de la croissance intra-utérine

Introduction: Le retard de croissance intra-utérin (RCIU) est défini comme une incapacité du foetus à atteindre son plein potentiel de croissance. C'est une complication fréquente (affectant ~8% des grossesses), associée à un risque accru de mortalité et morbidité périnatales et de maladies chroniques à l'âge adulte, telles que les maladies coronariennes, l'hypertension, ou le diabète. Une croissance foetale adéquate est déterminée principalement par la disponibilité en oxygène et nutriments apportés au foetus par la circulation ombilico-placentaire. Chez l'homme, le tonus vasculaire ombilical est régulé majoritairement par la voie du monoxyde d'azote (NO)/GMPc. Nous avons émis l'hypothèse que le RCIU pourrait être associé à des altérations dans la régulation de la circulation ombilicale, en particulier dans la voie du NO/GMPc. Méthodes: Cette étude a été conçue pour identifier dans des cordons ombilicaux, les changements structurels, fonctionnels et moléculaires survenant en cas de RCIU, en particulier dans la veine om-bilicale. Résultats: De façon générale, le diamètre du cordon ombilical était significativement réduit chez les nouveau-nés avec RCIU par rapport aux contrôles. Les mesures histomorphométriques ont mis en évidence une diminution significative de la surface transversale totale ainsi que de muscle lisse dans la veine ombilicale en cas de RCIU. Les études pharmacologiques effectuées sur des anneaux vasculaires de veines ombilicales ont montré une diminution de la tension maximale induite par des vasoconstricteurs chez les garçons avec RCIU, et une réduction significative de la relaxation induite par le NO chez les filles avec RCIU. Cette altération de la relaxation s'accompagne de modifications de plusieurs composants de la voie du NO/GMPc au niveau du muscle lisse de la veine ombilicale des filles avec RCIU. Enfin l'addition d'un inhibiteur non-spécifique des phosphodiesterases (PDEs) a permis d'améliorer la réponse au NO dans tous les groupes et surtout de compenser la réduction de la relaxation induite par le NO chez les filles avec RCIU. Conclusion: Cette étude a permis de mettre en évidence des modifications structurelles dans le cordon ombilical de nouveau-nés présentant un RCIU, ainsi que des changements fonctionnels et moléculaires dans la veine ombilicale, en particulier dans la voie du NO/GMPc, qui pourraient contribuer au développement du RCIU. L'effet bénéfique de l'inhibition des PDEs sur la relaxation suggère qu'elles pourraient constituer des cibles thérapeutiques potentielles.

Tomografia computadorizada das células etmoidais intra e extramurais: ensaio iconográfico

O desenvolvimento dos seios paranasais é um processo intricado que se inicia na vida intrauterina e termina na idade adulta. Dos seios da face, as células etmoidais são provavelmente as estruturas mais complexas e as que estão associadas com o maior número de variantes da normalidade. Variações no padrão de pneumatização das células etmoidais podem ser divididas em intra ou extramurais. Intramurais são aquelas que ao se desenvolverem mantêm contato com o labirinto etmoidal, e extramurais as que se desenvolvem isoladamente. A tomografia computadorizada é a ferramenta mais útil na avaliação de processos inflamatórios dos seios paranasais. De igual modo, ela é importante para o planejamento pré-operatório e controle pós-operatório, pois possibilita grande detalhe anatômico das estruturas normais e detecção precisa de suas variantes. Neste ensaio iconográfico os autores descrevem as principais variantes da normalidade do labirinto etmoidal e suas relações com estruturas adjacentes. Cirurgias endoscópicas para o tratamento de afecções dos seios paranasais têm-se tornado cada vez menos invasivas, o que certamente aumentará a demanda por relatórios de imagem cada vez mais ricos em detalhes desta região.

Resultate und ausser- gewöhnliche Komplikationen der Chirurgie der Gehörgangexostosen [Results and extraordinary complications of surgery for exostoses of the external auditory canal].

We present a retrospective study on 22 operations of exostosis of the external auditory canal in 20 patients. 8 patients were passionated by water sports. The most frequent indication for surgery (13 operations) was recurrent external otitis or ceruminal obstruction. In 7 cases the need for a wider access to the middle ear indicated surgery. Surgery was usually performed as an outpatient procedure, maximum hospitalization was 3 days. The mean healing period was 6 (3-10) weeks. Mean follow up was 43 (3-110) months. There were no severe intraoperative complications such as facial paresis, lesions of the ossicles or of the inner ear. As intraoperative complications we found 2 perforations of the tympanic membrane, 2 expositions of the capsule of the mandibular joint, one of which was followed by chronic pain. As postoperative complications we found an early soft tissue stenosis of the external auditory canal and one late soft tissue stenosis which recurred after revision surgery. No recurrence of exostosis was seen. We describe an up to now unknown complication: the appearance of bilateral petrositis caused by staphylococcus epidermidis after bilateral surgery in an otherwise healthy patient. This study confirms that severe complications are rare, minor ones however relatively common. And that also minor complications may have a troublesome follow. Therefore and because of the potential of severe complications indication for surgery must be made cautiously and risks of the operation must not be underestimated.

Les WNK kinases et les effets de WNK3 sur l'activité du canal ENaC

Les WNK kinases sont une famille de sérine/thréonine protéines kinases, des enzymes capables de phosphoryler le résidu OH de sérine ou thréonine. Quatre membres (WNK 1-4) ont été identifiés, largement distribués dans les cellules et tissus des mammifères et dont les fonctions sont de réguler des canaux ioniques et cotransporteurs. Leur particularité se situe au niveau de leur structure puisque une lysine a été substituée par une cystéine dans le domaine catalytique, d'où leur nom « with-no-lysine kinase » (McCormick and Ellison, 2011). Leur rôle dans le bon fonctionnement du rein et plus particulièrement dans le contrôle et maintien du bilan hydro-sodé n'est plus à vérifier puisque des mutations dans WNK 1 et WNK 4 sont connues pour causer la maladie de l'hypertension familiale ou syndrome de pseudohypoaldostéronisme de type 2, aussi appelé syndrome de Gordon (ou Fhht = Familial hyperkalaemic hypertension) (Furgeson and Linas, 2010). Le syndrome de Gordon est une maladie génétique autosomale dominante caractérisée par une hypertension, une hyperkaliémie et une acidose métabolique. Les WNKs contrôlent de nombreux canaux et transporteurs dans le rein, devenant des acteurs importants dans la régulation du bilan sodique et potassique. Leurs effets sont nombreux et variables et les canaux jouant un rôle clé dans cette régulation sont ENaC, NCC et ROMK (Kahle et al., 2008). Dans ce travail, nous commencerons par une partie théorique faisant le point sur l'organisation des néphrons et la régulation du bilan sodique et les différents mécanismes entrant en jeu. Nous intégrerons des informations générales concernant les WNKs ainsi qu'une revue plus détaillée de leurs effets respectifs dans le néphron. Pour terminer, nous aborderons les résultats d'une expérience qui a été réalisée en laboratoire sur des oocytes de Xenopus laevis. L'implication de WNK1 et WNK4 dans le contrôle du sodium ayant déjà été prouvée à de nombreuses reprises, nous nous sommes intéressés ici aux effets de WNK3 sur le canal ENaC ainsi que l'implication de Nedd4-2 dans ce procédé.

A randomized double-blind control study of early intra-coronary autologous bone marrow cell infusion in acute myocardial infarction: the REGENERATE-AMI clinical trial?.

AIMS: Clinical trials suggest that intracoronary delivery of autologous bone marrow-derived cells (BMCs) 1-7 days post-acute myocardial infarction (AMI) may improve left ventricular (LV) function. Earlier time points have not been evaluated. We sought to determine the effect of intracoronary autologous BMC on LV function when delivered within 24 h of successful reperfusion therapy. METHODS AND RESULTS: A multi-centre phase II randomized, double-blind, and placebo-controlled trial. One hundred patients with anterior AMI and significant regional wall motion abnormality were randomized to receive either intracoronary infusion of BMC or placebo (1:1) within 24 h of successful primary percutaneous intervention (PPCI). The primary endpoint was the change in left ventricular ejection fraction (LVEF) between baseline and 1 year as determined by advanced cardiac imaging. At 1 year, although LVEF increased compared with baseline in both groups, the between-group difference favouring BMC was small (2.2%; 95% confidence interval, CI: -0.5 to 5.0; P = 0.10). However, there was a significantly greater myocardial salvage index in the BMC-treated group compared with placebo (0.1%; 95% CI: 0.0-0.20; P = 0.048). Major adverse events were rare in both treatment groups. CONCLUSION: The early infusion of intracoronary BMC following PPCI for patients with AMI and regional wall motion abnormality leads to a small non-significant improvement in LVEF when compared with placebo; however, it may play an important role in infarct remodelling and myocardial salvage. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov NCT00765453 and EudraCT 2007-002144-16.

Alternativa al poder; establecimiento de poder: el discurso en el canal en YouTube de Podemos

Peer-reviewed

Anestésicos locais: interação com membranas biológicas e com o canal de sódio voltagem-dependente

Many theories about the mechanism of action of local anesthetics (LA) are described in the literature. Two types of theories can be distinguished: those that focus on the direct effects of LA on their target protein in the axon membranes, i.e. the voltage-gated sodium channel and the ones that take into account the interaction of anesthetic molecules with the lipid membrane phase for the reversible nerve blockage. Since there is a direct correlation between LA hydrophobicity and potency, it is crucial to take this physico-chemical property into account to understand the mechanism of action of LA, be it on the sodium channel protein, lipid(s), or on the whole membrane phase.