210 research outputs found
Self-aggregation of hydrophobically modified dextrin and their interaction with surfactant
A series of newly hydrophobically modified polymers (dexC16) with different degrees of substitution (DSC16) have been synthesized. They can self-assemble to form micelle-like aggregates through association of the hydrophobic alkyl chains in aqueous solution. The self-aggregation processes, i.e. the critical micelle concentrations (cmc's) of the polymers were characterized by steady-state fluorescence. Further, the interaction between these dexC16 polymers and ionic surfactants (SOS, SDS and DTAC) was investigated by isothermal titration calorimetry (ITC). For the studied mixed systems some important parameters can be derived from calorimetric titration curves, such as interaction enthalpies, critical concentrations and enthalpies of aggregation. The critical concentrations and the aggregation behaviour for the dexC16/SDS system were confirmed by fluorescence measurements. The effects of hydrophobic side group concentrations on the interaction were evaluated in detail. Importantly, we show that the aggregation behaviour of the mixed systems depends on the molar ratio of surfactant to hydrophobic side group (R = ns/nside group).Fundação para a Ciência e a Tecnologia (FCT
ANESTHESIA AND ANALGESIA IN ANTARCTIC FISH: AN EXPERIMENTAL APPROACH
Foi levado a efeito em peixes antárticos um estudo sobre as ações anestésicas e/ou analgésicas de
depressores centrais ketamine, fentanyl e thiopental bem como do anestésico local benzocaina. As drogas foram
adicionadas à água marinha aerada nas temperaturas de 1 a 1,5oC. Ketamine (15 mg/L) e fentanyl (50 g/L) não
induziram anestesia mas causaram demorada analgesia e sedação. Doses de 100 mg/L de Thiopental foram necessárias
para anestesiar peixes, ou seja, em concentração 30 vezes maior do que a dose anestésica usual utilizada para
mamÃferos. A anestesia ocasionada nos peixes foi longa - de 3 a 4 horas - e difÃcil de ser controlada. Um dos peixes
utilizados na experimentação permaneceu em estado de comatose por quatro dias com sobrevida. Benzocaina em
doses de 100 mg/L foi eficiente para anestesiar peixes dentro de 6 a 8 minutos após a sua administração. A anestesia,
neste caso, teve duração de 15 a 20 minutos acompanhada de pequena depressão respiratória.
Abstract
It was studied in Antarctic fishes the anesthetic and/or analgesic actions of central depressors
ketamine, fentanyl and thiopental as well as the local anesthetic benzocaine. The drugs were added to aerated
marine water at temperatures of 1-1.5 C. Ketamine (15 mg/L) and fentanyl (50 g/L) failed in inducing
anesthesia but caused a long lasting analgesia and sedation. Thiopental was required in doses of 100 mg/L to
anesthetize the fishes, that is, about 30 times higher than the usual anesthetic dose for mammals. The anesthesia
was long lasting, that is, 3-4 h, and difficult to control. One fish remained in a comatose state for four days with
survival. Benzocaine in doses of 100 mg/L was successful in anesthetizing the fishes within 6-8 min, anesthesia
lasting for 15-20 min, with a minor respiratory depression
Clinical Outcome and Morphologic Analysis after Endovascular Aneurysm Repair Using the Excluder Endograft
OBJECTIVE: Long-term follow-up after endovascular aneurysm repair (EVAR) is very scarce, and doubt remains regarding the durability of these procedures. We designed a retrospective cohort study to assess long-term clinical outcome and morphologic changes in patients with abdominal aortic aneurysms (AAAs) treated by EVAR using the Excluder endoprosthesis (W. L. Gore and Associates, Flagstaff, Ariz).
METHODS: From 2000 to 2007, 179 patients underwent EVAR in a tertiary institution. Clinical data were retrieved from a prospective database. All patients treated with the Excluder endoprosthesis were included. Computed tomography angiography (CTA) scans were retrospectively analyzed preoperatively, at 30 days, and at the last follow-up using dedicated tridimensional reconstruction software. For patients with complications, all remaining CTAs were also analyzed. The primary end point was clinical success. Secondary end points were freedom from reintervention, sac growth, types I and III endoleak, migration, conversion to open repair, and AAA-related death or rupture. Neck dilatation, renal function, and overall survival were also analyzed.
RESULTS: Included were 144 patients (88.2% men; mean age, 71.6 years). Aneurysms were ruptured in 4.9%. American Society of Anesthesiologists classification was III/IV in 61.8%. No patients were lost during a median follow-up of 5.0 years (interquartile range, 3.1-6.4; maximum, 11.2 years). Two patients died of medical complications ≤ 30 days after EVAR. The estimated primary clinical success rates at 5 and 10 years were 63.5% and 41.1%, and secondary clinical success rates were 78.3% and 58.3%, respectively. Sac growth was observed in 37 of 142 patients (26.1%). Cox regression showed type I endoleak during follow-up (hazard ratio, 3.74; P = .008), original design model (hazard ratio, 3.85; P = .001), and preoperative neck diameter (1.27 per mm increase, P = .006) were determinants of sac growth. Secondary interventions were required in 32 patients (22.5%). The estimated 10-year rate of AAA-related death or rupture was 2.1%. Overall life expectancy after AAA repair was 6.8 years.
CONCLUSIONS: EVAR using the Excluder endoprosthesis provides a safe and lasting treatment for AAA, despite the need for maintained surveillance and secondary interventions. At up to 11 years, the risk of AAA-related death or postimplantation rupture is remarkably low. The incidences of postimplantation sac growth and secondary intervention were greatly reduced after the introduction of the low-permeability design in 2004
Novel FGFR1 mutations in Kallmann syndrome and normosmic idiopathic hypogonadotropic hypogonadism: evidence for the involvement of an alternatively spliced isoform
OBJECTIVE:
To determine the prevalence of fibroblast growth factor receptor 1 (FGFR1) mutations and their predicted functional consequences in patients with idiopathic hypogonadotropic hypogonadism (IHH).
DESIGN:
Cross-sectional study.
SETTING:
Multicentric.
PATIENT(S):
Fifty unrelated patients with IHH (21 with Kallmann syndrome and 29 with normosmic IHH).
INTERVENTION(S):
None.
MAIN OUTCOME MEASURE(S):
Patients were screened for mutations in FGFR1. The functional consequences of mutations were predicted by in silico structural and conservation analysis.
RESULT(S):
Heterozygous FGFR1 mutations were identified in six (12%) kindreds. These consisted of frameshift mutations (p.Pro33-Alafs*17 and p.Tyr654*) and missense mutations in the signal peptide (p.Trp4Cys), in the D1 extracellular domain (p.Ser96Cys) and in the cytoplasmic tyrosine kinase domain (p.Met719Val). A missense mutation was identified in the alternatively spliced exon 8A (p.Ala353Thr) that exclusively affects the D3 extracellular domain of FGFR1 isoform IIIb. Structure-based and sequence-based prediction methods and the absence of these variants in 200 normal controls were all consistent with a critical role for the mutations in the activity of the receptor. Oligogenic inheritance (FGFR1/CHD7/PROKR2) was found in one patient.
CONCLUSION(S):
Two FGFR1 isoforms, IIIb and IIIc, result from alternative splicing of exons 8A and 8B, respectively. Loss-of-function of isoform IIIc is a cause of IHH, whereas isoform IIIb is thought to be redundant. Ours is the first report of normosmic IHH associated with a mutation in the alternatively spliced exon 8A and suggests that this disorder can be caused by defects in either of the two alternatively spliced FGFR1 isoform
Risk Factors, Dynamics, and Clinical Consequences of Aortic Neck Dilatation after Standard Endovascular Aneurysm Repair
Objective: Aortic neck dilatation (AND) occurs after endovascular aneurysm repair (EVAR) with self expanding stent grafts (SESs). Whether it continues, ultimately exceeding the endograft diameter leading to abdominal aortic aneurysm (AAA) rupture, remains uncertain. Dynamics, risk factors, and clinical relevance of AND were investigated after EVAR with standard SESs.
Methods: All intact EVAR patients treated from 2000 to 2015 at a tertiary institution were included. Demographic, anatomical, and device related characteristics were investigated as risk factors for AND. Outer to outer diameters were measured at a single standardised aortic level on reconstructed computed tomography (CT) images.
Results: A total of 460 patients were included (median follow up 5.2 years, interquartile range [IQR] 3.0, 7.7 years; CT imaging follow up 3.3 years, IQR 1.3, 5.4). Baseline neck diameter was 24 mm (IQR 22, 26) and increased 11.1% (IQR 1.5%, 21.9%) at last CT imaging. Endograft oversizing was 20.0% (IQR 13.6, 28.0). AND was greater during the first year (5.2% [IQR 0, 11.7]) decreasing subsequently (two to four years to 1.4%/year [IQR 0.0, 4.5%], p ≤ .001) and was associated with suprarenal fixation endografts (t value = 7.9, p 5 mm (HR 3.1, 95% CI 1.4 - 6.9).
Conclusion: AND after EVAR with SES is associated with endograft oversizing and radial force but decelerates after the first post-operative year. Baseline aortic neck diameter and suprarenal stent bearing endografts were associated with an increased risk of AND beyond nominal stent graft diameter. However, it remains unclear whether patient selection, differences in endograft radial force or the suprarenal stent are accountable for this difference.info:eu-repo/semantics/publishedVersio
Long-Term Outcomes of Standard Endovascular Aneurysm Repair in Patients With Severe Neck Angulation
Objective: Severe neck angulation is associated with complications after endovascular aneurysm repair (EVAR). Newer endografts may overcome this limitation, but the literature lacks long-term results. We studied the long-term outcomes of EVAR in patients with severe neck angulation.
Methods: A retrospective case-control study of a prospective multicenter database was performed. All measurements were made with dedicated software with center lumen line reconstruction. A study group including patients with neck length >15 mm, infrarenal angle (β) >75 degrees or suprarenal angle (α) >60 degrees, and neck length 10 to 15 mm with β >60 degrees or α >45 degrees was compared with a control group matched for demographics and other morphologic neck features. The primary end point was type IA endoleak (EL1A). Secondary end points were freedom from neck-related secondary interventions, primary clinical success, and overall survival.
Results: Forty-five patients were included in the angulated neck group and compared with 65 matched patients. Median follow-up was 7.4 years (interquartile range, 4.8-8.5 years). In the angulated neck group, mean α was 51.4 degrees (±21.1 degrees) and the mean β was 80.8 degrees (±15.6 degrees); in the nonangulated group, these were 17.9 degrees (±17.0 degrees) and 35.4 degrees (±20.0 degrees), respectively. At 7 years, five patients in the angulated neck group and two nonangulated patients developed EL1A, yielding a freedom from EL1A of 86.1% (n = 14; standard error [SE], 0.069) and 96.6% (n = 34; SE, 0.023), respectively (P = .056). After exclusion of a patient who developed an EL1A secondary to an endograft infection, this difference was significant: 86.1% (n = 14; SE, 0.069) in the angulated neck group and 98.2% (n = 34; SE, 0.018) in the nonangulated group (P = .016). At 7 years, freedom from neck-related secondary interventions was 91.7% (n = 14; SE, 0.059) and 91.6% (n = 29; SE, 0.029), respectively. The 7-year primary clinical success estimates were 41.2% (n = 11; SE, 0.085) and 56.6% (n = 20; SE, 0.072) for the angulated neck and nonangulated groups, respectively (P = .12). The 7-year survival rates were 44.3% (n = 18; SE, 0.076) vs 66.7% (n = 42; SE, 0.059) for the angulated neck and nonangulated groups, respectively (P = .25). Device integrity failure was not observed.
Conclusions: Despite satisfactory results early and in the midterm, a higher rate of EL1A was identified among patients with severely angulated necks in the long term. However, mortality was not affected by this difference. These findings suggest that EVAR should be used judiciously in patients with extreme angulation of the proximal neck and highlight the need for close follow-up of EVAR, especially in the long term and in patients treated outside instructions for use.info:eu-repo/semantics/publishedVersio
Chronic wasting disease risk assessment in Portugal: results and future work.
Número da Revista Portuguesa de Ciências Veterinárias, dedicado à publicação dos "Proceedings of the 10th Iberian Congress on Prions" que decorreu em Vila Real, Portugal de 19 1 20 de maio de 2022.Chronic wasting disease risk assessment in Portugal: results and future work.This work was supported by the project WastingPrionRisk [POCI-01-0145-FEDER-029947 / PTDC/
CVT-CVT/29947/2017] funded by the Portuguese Foundation for Science and Technology (FCT). FCT PhD grant [SFRH/BD/146961/2019] financed by FCT through FSE (Fundo Social Europeu). This work was also supported by national funds [UIDB/CVT/00772/2020], [LA/P/0059/2020] and [UIDB/04033/2020] by FCT.info:eu-repo/semantics/publishedVersio
Zoneamento agroecológico do dendezeiro para as áreas desmatadas do Pará.
O trabalho foi realizado com base nas informações de solo obtidas do banco de dados do SIPAM e de clima obtidas de várias fontes que dispunham de séries de dados de perÃodos não inferiores a 10 anos.PT2389
Filme biodegradável de base celulósica incorporado de óleos essenciais.
bitstream/item/98609/1/COT13006.pd
- …