Dor em portadores de próteses totais primárias da anca: causas e avaliação clínica

Apesar da prótese total primária da anca ser referenciada como uma das endopróteses com maior sucesso em Ortopedia, uma pequena percentagem de doentes desenvolve um quadro doloroso localizado na anca num curto, médio ou a longo prazo, que pode ou não ser provocado pelo implante. A razão da persistência da dor após a implantação de uma prótese da anca pode ser sustentada por fatores intrínsecos, por fatores extrínsecos loco-regionais ou por outros fatores extrínsecos. O estudo das próteses da anca não pode ser feito isoladamente, deve estar integrado no complexo funcional vertebro-pélvico-femoral. Assim, tendinopatias dos músculos glúteos, do psoas-ilíaco, dos adutores, dos isquiotíbiais ou as afeções da coluna lombar, da articulação sacroilíaca ou do joelho homolateral e, ainda, afeções vasculares, nervosas e fatores psicológicos podem justificar a presença da dor. Neste contexto, o desprendimento assético e a infeção periprotética são dois importantes fatores que poderão estar na origem da dor na anca após uma prótese total da anca e devem, desde logo, ser excluídos antes de se considerarem outras causas menos comuns. Se não existir, aparentemente, uma razão que justifique a dor, o doente deve ser considerado como tendo uma infeção periprotética até prova do contrário. A anamnese e o exame físico, complementados por provas laboratoriais sanguíneas e do aspirado articular ou periarticular e, ainda, pelos exames imagiológicos, constituem os pilares sobre os quais assenta o diagnóstico das diferentes afeções que podem estar na génese da dor. Com efeito, o hemograma com fórmula leucocitária, a velocidade de sedimentação, a proteína C reativa, os exames radiográficos em diferentes incidências, a ecografia, a artrocentese com estudo citológico, microbiológico, cultura e antibiograma do aspirado articular, a tomografia axial computorizada quando indicada, são instrumentos valiosos para se conseguir alcançar um diagnóstico definitivo. Identificada a etiologia da dor, torna-se possível definir a estratégia terapêutica mais indicada, que é necessariamente diferente de um caso para outro. Constitui um princípio crucial só iniciar a terapêutica após o conhecimento do diagnóstico, quer se trate de uma abordagem conservadora ou, sobretudo, de uma intervenção cirúrgica. As dores inexplicáveis, de causa desconhecida, não encontram indicação para uma intervenção cirúrgica, assim como não é de aceitar a origem periarticular da dor sem terem sido eliminadas todas as causas de dor relacionadas com a prótese. A intervenção cirúrgica com a finalidade de se proceder a uma eventual recolocação artroplástica, sem prévio esclarecimento da etiologia da dor, não é uma boa prática produz, muitas vezes, um pobre resultado clínico

G-quadruplexes and their ligands: Biophysical methods to unravel g-quadruplex/ligand interactions

Funding Information: (PD/00065/2013). This work was supported by PESSOA program ref. 5079 and project “Projeto de Investigação Exploratória” ref. IF/00959/2015 entitled “NCL targeting by G-quadruplex aptamers for cervical cancer therapy” financed by Fundo Social Europeu e Programa Operacional Potencial Humano. Thanks are due to FCT/MCT for the financial support of the CICS-UBI UIDB/00709/2020 research unit and to the Portuguese NMR Network (ROTEIRO/0031/2013-PINFRA/22161/2016), through national funds and, where applicable, supported by European Investment Funds FEDER through COMPETE 2020, POCI, PORL and PIDDAC.Progress in the design of G-quadruplex (G4) binding ligands relies on the availability of approaches that assess the binding mode and nature of the interactions between G4 forming sequences and their putative ligands. The experimental approaches used to characterize G4/ligand interactions can be categorized into structure-based methods (circular dichroism (CD), nuclear magnetic resonance (NMR) spectroscopy and X-ray crystallography), affinity and apparent affinity-based methods (surface plasmon resonance (SPR), isothermal titration calorimetry (ITC) and mass spectrometry (MS)), and high-throughput methods (fluorescence resonance energy transfer (FRET)-melting, G4-fluorescent intercalator displacement assay (G4-FID), affinity chromatography and microarrays. Each method has unique advantages and drawbacks, which makes it essential to select the ideal strategies for the biological question being addressed. The structural-and affinity and apparent affinity-based methods are in several cases complex and/or time-consuming and can be combined with fast and cheap high-throughput approaches to improve the design and development of new potential G4 ligands. In recent years, the joint use of these techniques permitted the discovery of a huge number of G4 ligands investigated for diagnostic and therapeutic purposes. Overall, this review article highlights in detail the most commonly used approaches to characterize the G4/ligand interactions, as well as the applications and types of information that can be obtained from the use of each technique.publishersversionpublishe

Urgent-Start Peritoneal Dialysis – a viable option? A case report and literature review

Background: Many patients with end -stage renal disease start renal replacement therapy in an unplanned manner. The vast majority initiate hemodialysis by a central venous catheter, since its use is more widespread and available. This technique is associated with a high risk of infection and damage of the vascular patrimony associated with the use of central veins. Urgent -start peritoneal dialysis comes as an alternative treatment for selected patients. Case report: A 55 -year -old woman with focal segmental glomerulosclerosis presented with a rapid decline of renal function and was given renal replacement therapy counselling and opted for peritoneal dialysis. Her chosen modality was postponed for one month due to early uremic symptoms, followed by hemodialysis start through a central venous catheter. During this period a sepsis due to central venous catheter infection occurred, implying four weeks of intravenous antibiotics. Discussion and Conclusion: Although there has been an increase in the number of publications on urgent -start peritoneal dialysis, showing that this technique has comparable results either to urgent -start hemodialysis and planned -start peritoneal dialysis, there still is some resistance to the use of this modality. Given the importance of this subject, this review aims to describe and summarize the available evidence on urgent -start peritoneal dialysis outcomes. Moreover, specific barriers are addressed. Its use is encouraged in hospitals where peritoneal dialysis is available, as an opportunity to improve chronic kidney disease patient management and transition to dialysis.info:eu-repo/semantics/publishedVersio

Undifferentiated Sarcoma of the Liver in the Adult

Os AA apresentam um caso clínico de sarcoma indiferenciado do fígado no adulto com metástases pulmonares, cardíacas e com recidiva local hepática. Salienta-se a contribuição dos exames complementares de diagnóstico, com especial relevo para a ecocardiografia no diagnóstico precoce de metástases intracardiacas. Não encontrámos qualquer outro caso descrito na literatura portuguesa

Epitope Mapping by NMR of a Novel Anti-Aβ Antibody (STAB-MAb)

FP7-SP3-People-606950 POCI-01-0145-FEDER-007728 Project No 022161Alzheimer´s Disease (AD) is one of the most common neurodegenerative disorders worldwide. Excess of β-amyloid (Aβ), a peptide with a high propensity to misfold and self-aggregate, is believed to be the major contributor to the observed neuronal degeneration and cognitive decline in AD. Here, we characterize the epitope of a novel anti-Aβ monoclonal antibody, the STAB-MAb, which has previously demonstrated picomolar affinities for both monomers (KD = 80 pM) and fibrils (KD = 130 pM) of Aβ(1–42) and has shown therapeutic efficacy in preclinical mouse models of AD. Our findings reveal a widespread epitope that embraces several key Aβ residues that have been previously described as important in the Aβ fibrillation process. Of note, STAB-MAb exhibits a stronger affinity for the N-terminus of Aβ and stabilizes an α-helix conformation in the central to N-terminal region of the peptide, in addition to disrupting a characteristic salt-bridge of a hairpin structure present in fibrils. The NMR derived epitope supports the observed results from ThT-monitored fluorescence and electron microscopy experiments, in which STAB-MAb was shown to inhibit the formation of aggregates and promote disruption of pre-formed fibrils. In combination with the published in vitro and in vivo assays, our study highlights STAB-MAb as a rare and versatile antibody with analytical, diagnostic and therapeutic efficacy.publishersversionpublishe

Are we building too many arteriovenous fistulas? A single-center experience

Introduction: Arteriovenous fistula has been associated with improved morbimortality in hemodialysis patients. This has resulted in the “fistula First, catheter last” initiative. Nonetheless, the survival benefit of arteriovenous fistula has been questioned. Methods: We conducted a retrospective observational study of all patients with non-end stage renal disease referred for first vascular access building between January 2014 and December 2015 in our hospital center. Our main goal was to evaluate the clinical impact and burden of building fistula in predialysis patients. Results: During this period, of 178 first arteriovenous accesses placed, 87 patients remained in predialysis and 91 patients started a chronic hemodialysis program. Median follow-up time by a nephrologist was 3.9 (2.5, 9.7) years. The mean age was 65.8±14.7 years, with 50.6% (n=90) of male patients. A higher rate of thrombosis in the predialysis group (26% vs 13%, p=0.037) was observed, but vascular access survival did not differ significantly (55% vs 67%, p=0.12). Mean vascular access placing was higher in the predialysis group (1.4±0.7 vs 1.2±0.4, p=0.006) and less interventions were requested (0.2±0.5 vs 0.3±0.6, p=0.10). Median time from vascular access placement to hemodialysis start was 22 (13, 41) months. At hemodialysis initiation, 10 (10.9%) patients used a central venous catheter; 80 (87.9%) patients an arteriovenous fistula, and one patient a graft. A total of 227 vascular accesses were built; 121 (53.3%) in predialysis vs 106 (46.7%) in incident hemodialysis patients. In a multivariate model, the presence of a functional arteriovenous fistula at hemodialysis start was only associated with a trend to survival benefit (HR 0.38, 95% CI 0.14-1.00, p=0.05). Conclusions: Our results stress the need for an individual approach and for future tools to assess the risk of death and progression to end-stage renal disease, therefore helping reduce the number of unutilized vascular accesses and rising cost of interventions.info:eu-repo/semantics/publishedVersio

Arterio-arterial graft – an option for hemodialysis patients with exhaustion of venous patrimony

Introduction: Vascular access (VA) for hemodialysis (HD) is the lifeline for End Stage Renal Disease (ESRD) patients. Long-term HD patients often have exhaustion of their venous patrimony for an autologous VA construction and, sometimes, even for a central venous catheter (CVC) placement. Case report: We describe the case of a 43-year-old woman with ESRD due to lupus nephritis, on maintenance HD since 2009. She also had secondary antiphospholipid syndrome and was chronically anticoagulated. Nevertheless, the patient had multiorgan thrombotic events (without sequelae) and several episodes of irreversible thrombosis of arteriovenous fistulas. Her HD course was also marked by multiple severe CVC infections, at diferente locations; a hemoperitoneum during cholecystectomy, and an immediate thrombosis of the renal artery of a kidney transplant. She was admitted to our hospital after an irreversible dysfunction of a right jugular CVC, with documentation of thrombosis of the superior and inferior vena cava. Exhaustion of the venous patrimony for HD was assumed and it was decided to make an arterio-arterial graft (AAG) of early cannulation. The first cannulation of the AAG was performed two days after surgical intervention, with no complications. The patient performed a twelve hour per week HD treatment with good efficiency. Conclusion: AAG is an alternative for HD patients who have exhausted all their venous patrimony and it can be considered prior to the placement of a CVC as their sole remaining vascular access.info:eu-repo/semantics/publishedVersio

Acute tubulointersticial nephritis with uveitis: A report of two cases

Tubulointersticial nephritis and uveitis syndrome is an idiopathic and rare cause of acute kidney injury that should not overlooked, because it usually requires specific therapeutic interventions. We report two distinct cases: a young and an elder female. Both cases presented with unspecific constitutional symptoms but had different onset of renal and ocular involvement. Both were treated with topical and systemic corticoids and although there was a good initial response in both cases, an early relapse after steroids taper was observed in the younger patient and a persistent renal dysfunction in the older one. A high clinical suspicion and understanding of this disease is necessary for an adequate management and treatment of these patients. Recent data associates a worse renal prognosis when the disease appears in advanced age. In both of our cases the outcome was good but we had a short follow-up. The histological presentation of this disease in our older patient was similar to that reported in the literature, with a high percentage of fibrosis and chronicity of renal tissue that can contribute to the higher grade of renal dysfunction in this type of patients.info:eu-repo/semantics/publishedVersio

Techniques of intestinal transplantation in rat

Two surgical models of intestinal transplantation in the rat are described. One is the implantation of fetal and newborn intestine as free grafts into the omentum of adult recipients, the other the adult intestine transplantation as an accessory graft using vascular anastomoses. A hundred and sixteen small-bowel transplantations were done; 36 of which were fetal intestine (group I), 40 of newborn intestine (group II), and 40 of adult intestine (group III). In the fetal and newborn intestinal transplantation, we emphasize the practices that allowed us to avoid ischemic and traumatic injury to the graft. In the adult intestine transplantation with vascular anastomoses, we heighten the modifications in the surgical technique that made the operation easier and the strategies used to prevent hypothermia and hypovolemic shock. Once experienced with the two chosen surgical techniques, transplantation using an avascular segment became much easier and quicker than transplantation with vascular anastomoses. © 1998 Wiley-Liss, Inc. MICROSURGERY 18:424-429, 199

Overhydration prevalence in peritoneal dialysis - A 2 year longitudinal analysis

Hypervolemia is a major concern in dialysis patients, and is associated with increased cardiovascular risk and death. Cross sectional analysis have previously demonstrated that peritoneal dialysis (PD) patients are not more overhydrated when compared to haemodialysiś ones. This study was designed to evaluate longitudinal trends in hydration status and corporal composition in a PD population.Pedro Ventura Aguiar, by Abbott laboratory for conferences presentation