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Connectivity of landslide sediment to and within fluvial systems is a key factor affecting the extent of mobilization of hillslope material. In particular, the formation of landslide dams and the transformation into landslide-induced debris flows represent “end members” of landslide sediment mobility. To quantify sediment connectivity, we developed a two-segment flume representing tributary inflow and the main channel. Mobility of sediment was examined by combinations of various topographic factors, such as tributary inflow angle (0 to 90° in 30° increments) and main channel gradient (10° and 15°), as well as water content of sediment (0 to 100% in 20% increments). We also examined differences of mobility among sediments derived from various lithologies (sand and shale, pyroclastic sediment, weathered granite, and weathered sedimentary rock). Mobility of sediment differed, depending on the water content of sediment, particularly less than saturation or greater than saturation. When all types of unsaturated landslide sediments entered the channel at inflow angles of 60° and 90°, substantial deposition occurred, suggesting the formation of landslide dams. At low inflow angles (0° and 30°) in a steep channel (15°), >50% of landslide sediment was transported downstream, indicating the occurrence of a debris flow. The amount of sediment deposited at the junction angle was greater for pyroclastic sediment followed by weathered granite, weathered sedimentary rock, and finally, sand and shale. Our connectivity index suggests that a threshold exists between landslide dam formation and debris flow occurrence associated with topographic conditions, water content, and types of sediment.

Resumo Fundamento A regurgitação valvar pulmonar é uma importante complicação de longo prazo em pacientes com tetralogia de Fallot (TF). Objetivo O presente estudo tem como objetivo investigar os efeitos do implante valvar pulmonar (IVP) na anatomia e função do ventrículo direito (VD) e na evolução em longo prazo da prótese implantada em posição pulmonar. Métodos Uma análise de coorte retrospectiva e unicêntrica foi realizada em 56 pacientes consecutivos com TF submetidos a IVP. O estudo incluiu pacientes de ambos os gêneros, com idade ≥ 12 anos e compreendeu avaliação de dados clínicos e cirúrgicos, ressonância magnética cardiovascular pré e pós-operatória e dados ecocardiográficos obtidos mais de 1 ano após IVP. Resultados Após o IVP, houve uma diminuição significativa do volume sistólico final do VD indexado pela área de superfície corpórea (ASC), de 89 mL/ASC para 69 mL/ASC (p < 0,001) e do volume diastólico final indexado do VD, de 157 mL/ASC para 116 mL/ASC (p < 0,001). Além disso, houve aumento da fração de ejeção corrigida do VD [ FEVDc = fluxo pulmonar ajustado (fluxo pulmonar anterógrado − fluxo regurgitante) / volume diastólico final do VD ] de 23% para 35% (p < 0,001) e da fração de ejeção do ventrículo esquerdo de 58% para 60% (p = 0,008). No entanto, foi observado um aumento progressivo no gradiente de pico da válvula pulmonar ao longo do tempo, com 25% dos pacientes apresentando um gradiente superior a 60 mmHg. Próteses menores (tamanhos 19 a 23) foram associadas a um risco 4,3 vezes maior de gradiente > 60 mmHg em comparação com próteses maiores (tamanhos 25 a 27; p = 0,029; intervalo de confiança: 1,18 a 17,8). Conclusão Conforme esperado, o IVP demonstrou melhorias nos volumes e na função do VD. O acompanhamento e a vigilância a longo prazo são cruciais para avaliar a durabilidade da prótese e detectar potenciais complicações. O dimensionamento adequado das próteses é essencial para melhorar a longevidade da prótese.

Giant cell arteritis (GCA) is a type of chronic vasculitis that affects medium and large-caliber arteries, frequently related to aortic involvement and, consequently, to aneurysm formation. However, associated valvulitis with giant cells is uncommon. We describe the case of a 50-year-old female patient with aortic aneurysm and valvular insufficiency, whose anatomopathological examination revealed giant-cell aortic valvulitis associated with giant cell aortitis.

Abstract Left ventricular hypertrophy is a risk factor for cardiovascular mortality in patients on peritoneal dialysis (PD). Because icodextrin has a greater ultrafiltration power compared with glucose-based solutions for long dwell, it could improve left ventricular mass by reducing fluid overload. This was a randomized clinical trial that included patients on PD recruited from 2 teaching hospitals, in Sao Paulo—Brazil. Patients were allocated to the control glucose group (GLU) or the intervention icodextrin (ICO) group. Clinical and cardiac magnetic resonance image (MRI) parameters were evaluated at baseline and 6 months after randomization. The primary outcome was the change in left ventricular mass adjusted by surface area (ΔLVMI), measured by cardiac MRI. A total of 22 patients completed the study (GLU, N = 12 and ICO, N = 10). Baseline characteristics such as age, sex, underlying disease, and time on dialysis were similar in both groups. At baseline, 17 patients (77.3%) presented with left ventricular hypertrophy with no difference between groups (p = 0.748). According to the total body water (TBW)/extracellular water (ECW) ratio, 36.8% and 80% of patients from GLU and ICO groups, respectively, were considered hypervolemic (p = 0.044). During follow-up, ΔLVMI was 3.9 g/m (− 10.7, 2.2) in GLU and 5.2 (− 26.8, 16.8) in ICO group (p = 0.651). ΔLVMI correlated with change in brain natriuretic peptide (r = 0.566, p = 0.044), which remained significant in a multiple regression analysis. The use of the icodextrin-based solution in prevalent patients on PD compared with a glucose-based solution was not able to improve LMV. A larger randomized trial with a longer follow-up period may be needed to show changes in LVM in this patient population. Trial registration: this study has been registered at ReBEC (Registro Brasileiro de Ensaios Clinicos) under the identification #RBR-2mzhmj2, available at: https://ensaiosclinicos.gov.br/pesquisador .