Synthesis of sub-5 nm Co-doped SnO2_2 nanoparticles and their structural, microstructural, optical and photocatalytic properties

A swift chemical route to synthesize Co-doped SnO$_2$ nanopowders is described. Pure and highly stable Sn$_{1-x}$Co$_x$O$_{2-\delta}$ (0 $\le$ x $\le$ 0.15) crystalline nanoparticles were synthesized, with mean grain sizes < 5 nm and the dopant element homogeneously distributed in substitutional sites of the SnO$_2$ matrix. The UV-visible diffuse reflectance spectra of the Sn$_{1-x}$Co$_x$O$_{2-\delta}$ samples reveal red shifts, the optical bandgap energies decreasing with increasing Co concentration. The Urbach energies of the samples were calculated and correlated with their bandgap energies. The photocatalytic activity of the Sn$_{1-x}$Co$_x$O$_{2-\delta}$ samples was investigated for the 4-hydroxylbenzoic acid (4-HBA) degradation process. A complete photodegradation of a 10 ppm 4-HBA solution was achieved using 0.02% (w/w) of Sn$_{0.95}$Co$_{0.05}$O$_{2-\delta}$ nanoparticles in 60 min of irradiation.Comment: 29 pages, 2 tables, 10 figure

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

Peritoneal dialysis dropouts in different age and era cohorts: focus on the elderly

Introduction and Aims: Peritoneal dialysis (PD) is an efficient renal replacement therapy (RRT), but still remains underutilized at any age. Clinicians fear the rate of dropouts and lower technique survival, particularly in elderly patients. The authors aimed to explore such outcomes over the past 3 decades, in different age and era cohorts. Methods: Consecutive incident patients starting PD were identified from an ongoing registry-base prospective study of quality assessment. In order to control for an era effect, patients were assigned to 6 cohorts (5 years interval) according to the admission year between 1985 and 2014. Regression models taking competing risks into account were performed to identify potential prognostic factors for death and transfer to haemodialysis (HD) (adjusted for age, gender, diabetes, cohort era, automated peritoneal dialysis (APD) use, and first treatment modality – PD first, PD after HD, PD after renal transplant (RT). Then the patients were studied according to age at enrolment in the programme: A (18 44 years; n = 193); B (45 64 years; n = 176) and C (≥ 65 years old; n = 75). The HD transfer rates using Poisson analysis were evaluated. The incidence of dropout rates was compared at different times and between age groups, focusing particular attention on the elderly. Results: A total of 525 patients were evaluated: 211 male (40.2%), aged 48 ± 15.7 years old, on PD for 23 (IQR 9 – 41.5) months. The major cause of dropout technique was transfer to HD (35.4%), followed by renal transplantation (27.6%) and death (21.7%). The probability of technical failure and renal transplantation at 2 and 5 years was 19.2% and 18.1% and 34.2%; 27.4%, respectively. Probability of death at 2 and 5 years was 12.7%, and 21.8%, respectively. The contemporary cohort was associated with a lower risk of mortality and lower risk of transfer to haemodialysis, with greater access to renal transplantation. The regression model Fine & Gray showed that older age was associated with increased mortality, but was not associated with greater technical failure. Transfer to HD occurred in the elderly at a rate of 11epy/100 patient year (in comparison to 15 and 14 epy/100 patient-year in non-elderly groups A and B, respectively P= 0.33). The proportions of specific causes of technique failure did not change significantly according to age cohort. The dropout rates due to access-related-infection and ultrafiltration failure decreased in the elderly group in the more contemporary cohort, despite the differences were not statistically significant. Conclusions: The dropout by technique failure decreased significantly in the recent decade. Age at admission in peritoneal dialysis did not show to be a compromising factor of the technique survivalIntrodução e Objetivos: A diálise peritoneal (DP) é uma técnica substitutiva da função renal (TSFR) com eficácia semelhante à hemodiálise (HD); no entanto, ainda permanece subutilizada em qualquer idade. Os médicos temem o elevado drop-out da técnica e a sua menor sobrevida, particularmente nos doentes idosos. Os autores pretenderam explorar causas de drop-out e sobrevida da técnica ao longo das últimas três décadas, em diferentes faixas etárias, centrando uma atenção particular no idoso. Métodos: Foram usados dados do registo prospetivo do programa hospitalar de doentes adultos incidentes em DP. Tendo em conta as diferentes épocas, os doentes foram divididos em 6 coortes (5 anos de intervalo) de acordo com o ano de admissão no programa (1985-2014). Usaram-se modelos de regressão tendo em conta a análise de riscos competitivos para identificar potenciais fatores de prognóstico para a morte e transferência para HD (ajustados para a idade, género, diabetes, era, tipo de técnica e primeira modalidade de TSFR). Posteriormente, os doentes foram estudados de acordo com a idade à admissão no programa: A (18 44 anos); B (45 64 anos) e C (≥ 65 anos de idade). Foram avaliadas as taxas de transferência para HD usando a análise de Poisson. As taxas de incidência de drop-out foram comparadas em diferentes épocas e entre os grupos etários, focando particular atenção no doente idoso. Resultados: Foram avaliados 525 pacientes: 211 eram do sexo masculino (40,2%), com idade média de 48 ± 15,7 anos, com follow-up mediano de 23 meses (IQR 9-41,5). A maior causa de drop-out da técnica foi a transferência para HD (35,4%), seguida do transplante renal (27,6%) e de morte (21,7%). A probabilidade de falência técnica e transplantação renal aos 2 e aos 5 anos foi 19,2% e 18,1% e 34,2%; 27,4%, respetivamente. A probabilidade de morte aos 2 e aos 5 anos foi 12,7%, e 21,8%, respetivamente. A coorte mais recente associou-se a menor risco de mortalidade e menor transferência para HD. O modelo de regressão Fine & Gray mostrou que a idade avançada se associou a maior mortalidade, contudo não se associou a maior falência técnica. Nos idosos, a taxa de transferência para HD foi 11,2 episódios/100 doentes-ano (em comparação com 15 e 14 episódios/100 doentes-ano nos grupos A e B, respectivamente, p= 0,33). Não houve diferenças significativas nas causas de transferência para HD entre os diferentes grupos etários. As taxas de drop-out por falência de acessos e por falência de ultrafiltração diminuíram no grupo mais velho e na coorte mais recente, contudo as diferenças não foram estatisticamente significativas entre os grupos. Conclusões: O drop-out por falência técnica diminuiu significativamente na década mais recente. A idade de admissão na diálise peritoneal não mostrou ser um fator de comprometimento da sobrevida da técnic

Hepatocyte growth factor signalizes peritoneal membrane failure in peritoneal dialysis

BACKGROUND: Hepatocyte growth factor (HGF) counteracts peritoneal fibrosis in animal models and in-vitro studies, but no study explored effluent HGF in peritoneal dialysis (PD) patients with ultrafiltration failure (UFF). Our aim was to assess the relationship between effluent HGF with UF profile, free water transport (FWT) and small-solute transport. METHODS: We performed 4-hour, 3.86% PET with additional UF measurement at 60 minutes in 68 PD patients. MTACcreatinine, FWT, small-pore ultrafiltration, and effluent HGF were quantified. RESULTS: Effluent HGF negatively correlated with UF (r=-0.80, p=0.009) and FWT (r=-0.69, p=0.04). Patients with UFF had higher dialysate HGF (103 pg/mL vs 77 pg/mL, p=0.018) and, although not statistically significant, those with FWT compromise had also higher dialysate HGF compared with subgroup of UFF without FWT compromise (104 pg/mL vs 88 pg/mL, p=0.08). FWT≤45% without clinical UFF was documented in some patients who also had increased effluent HGF. CONCLUSIONS: Dialysate HGF concentration is significantly higher among patients with UFF, specially, if FWT is impaired, being a sign of peritoneal membrane deterioration.This study was partially performed with the help of investigations grants from Sociedade Portuguesa de Nefrologia. This work was also supported by UMIB/ICBAS – University of Porto (UP). Multidisciplinary Unit for Biomedical Research (UMIB) is funded by grants from Foundation for Science and Technology (Fcomp-01-0124-FEDER-015896

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

Monoclonal gammopathy of renal significance: Diagnostic workup

The clinical spectrum of diseases associated with monoclonal gammopathies is wide and they are most commonly the consequence of renal deposition of monoclonal immunoglobulin or its components. The differential diagnosis is difficult and renal biopsy is essential. To distinguish many of these pathologies is necessary to use techniques that are not always available, even in tertiary central hospitals. This review will discuss the clinical presentation, pathologic features, treatment, prognosis and common diagnostic difficulties of these entities.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

Different kidney function trajectory patterns before dialysis in elderly patients: clinical implications and outcomes

Background. Identifying trajectories of kidney disease progression in chronic kidney disease (CKD) patients may help to deliver better care. We aimed to identify and characterize trajectories of renal function decline in CKD patients and to investigate their association with mortality after dialysis.Methods. This retrospective cohort study included 378 CKD patients who initiated dialysis (aged 65 years and over) between 2009 and 2016. Were considered mixed models using linear quadratic and cubic models to define the trajectories, and we used probabilistic clustering procedures. Patient characteristics and care practices at and before dialysis were examined by multivariable multinomial logistic regression. The association of these trajectories with mortality after dialysis was examined using Cox models.Results. Four distinct groups of eGFR trajectories decline before dialysis were identified: slower decline (18.3%), gradual decline (18.3%), early rapid decline (41.2%), and rapid decline (22.2%). Patients with rapid eGFR decline were more likely to have diabetes, more cognitive impairment, to have been hospitalized before dialysis, and were less likely to have received pre-dialysis care compared to the patients with a slower decline. They had a higher risk of death within the first and fourth year after dialysis initiation, and after being more than 4 years in dialysis.Conclusions. There are different patterns of eGFR trajectories before dialysis initiation in the elderly, that may help to identify those who are more likely to experience an accelerated decline in kidney function, with impact on pre ESKD care and in the mortality risk after dialysis

A novel pentacyclic triterpene from Leontodon filii

A novel oleanene triterpenetetrol was isolated from the chloroform extract of the aerial parts of Leontodon filii. Its structure was shown to be 2β,3β,15α,21β-olean-12-ene-2,3,15,21-tetrol by chemical and spectroscopic methods. The fungicidal efficacy of the chloroform and methanol extracts of the plant was also evaluated, a protective effect being found against Plasmopara viticola, Botrytis cinerea, particularly powerful against Pyricularia oryzae.info:eu-repo/semantics/publishedVersio