172 research outputs found
Cognitive predictors of balance in Parkinson's disease
Postural instability is one of the most incapacitating symptoms of Parkinsons disease (PD) and appears to be related to cognitive deficits. This study aims to determine the cognitive factors that can predict deficits in static and dynamic balance in individuals with PD. A sociodemographic questionnaire characterized 52 individuals with PD for this work. The Trail Making Test, Rule Shift Cards Test, and Digit Span Test assessed the executive functions. The static balance was assessed using a plantar pressure platform, and dynamic balance was based on the Timed Up and Go Test. The results were statistically analysed using SPSS Statistics software through linear regression analysis. The results show that a statistically significant model based on cognitive outcomes was able to explain the variance of motor variables. Also, the explanatory value of the model tended to increase with the addition of individual and clinical variables, although the resulting model was not statistically significant The model explained 25-29% of the variability of the Timed Up and Go Test, while for the anteroposterior displacement it was 23-34%, and for the mediolateral displacement it was 24-39%. From the findings, we conclude that the cognitive performance, especially the executive functions, is a predictor of balance deficit in individuals with PD
Influence of dual-task on sit-to-stand-to-sit postural control in Parkinson's disease
Postural control deficits are the most disabling aspects of Parkinson's disease (PD), resulting in decreased mobility and functional independence. The aim of this study was to assess the postural control stability, revealed by variables based on the centre of pressure (CoP), in individuals with PD while performing a sit-to-stand-to-sit sequence under single- and dual-task conditions. An observational, analytical and cross-sectional study was performed. The sample consisted of 9 individuals with PD and 9 healthy controls. A force platform was used to measure the CoP displacement and velocity during the sit-to-stand-to-sit sequence. The results were statistically analysed. Individuals with PD required greater durations for the sit-to-stand-to-sit sequence than the controls (p < 0.05). The anteroposterior and mediolateral CoP displacement were higher in the individuals with PD (p < 0.05). However, only the anteroposterior CoP velocity in the stand-to-sit phase (p = 0.006) was lower in the same individuals. Comparing the single- and dual-task conditions in both groups, the duration, the anteroposterior CoP displacement and velocity were higher in the dual-task condition (p < 0.05). The individuals with PD presented reduced postural control stability during the sit-to-stand-to-sit sequence, especially when under the dual-task condition. These individuals have deficits not only in motor performance, but also in cognitive performance when performing the sit-to-stand-to-sit sequence in their daily life tasks. Moreover, both deficits tend to be intensified when two tasks are performed simultaneously
Marine-inspired drugs and biomaterials in the perspective of pancreatic cancer therapies
Despite its low prevalence, pancreatic cancer (PC) is one of the deadliest, typically characterised as silent in early stages and with a dramatically poor prognosis when in its advanced stages, commonly associated with a high degree of metastasis. Many efforts have been made in pursuing innovative therapeutical approaches, from the search for new cytotoxic drugs and other bioactive compounds, to the development of more targeted approaches, including improved drug delivery devices. Marine biotechnology has been contributing to this quest by providing new chemical leads and materials originating from different organisms. In this review, marine biodiscovery for PC is addressed, particularly regarding marine invertebrates (namely sponges, molluscs, and bryozoans), seaweeds, fungi, and bacteria. In addition, the development of biomaterials based on marine-originating compounds, particularly chitosan, fucoidan, and alginate, for the production of advanced cancer therapies, is also discussed. The key role that drug delivery can play in new cancer treatments is highlighted, as therapeutical outcomes need to be improved to give further hope to patients.The authors would like to acknowledge the funding from the European Union Framework Program for Research and Innovation Horizon 2020 through project SponGES (H2020-BG-01-2015-679849) and from the European Regional Development Fund, through INTERREG España-Portugal 2014-2020 under BLUEBIOLAB (0474_BLUEBIOLAB_1_E) project and through NORTE2020/PT2020 Programme under ATLANTIDA (Norte-01-0145-FEDER-000040) project
DNA extraction from plant food supplements: Influence of different pharmaceutical excipients
The consumption of plant food supplements (PFS) has been growing globally, with an increase of misleading labeling and fraudulent practices also being reported. Recently, the use of molecular biology techniques has been proposed to detect botanical adulterations, one of the possible frauds in PFS. However, difficulties in recovering DNA from some PFS samples have been described. Aiming at using DNA-based methods for the unequivocal identification of plant species in PFS, adequate DNA isolation is required. However, PFS often contain pharmaceutical excipients known to have adsorbent properties that might interfere with DNA extraction. Thus, the aim of this work was to assess the effect of different excipients (talc, silica, iron oxide and titanium dioxide) on the recovery/amplification of DNA. For that purpose, known amounts of template maize DNA were spiked either to PFS or to model mixtures of excipients and quantified by real-time PCR. The tested excipients evidenced clear adsorption phenomena that justify the hampering effect on DNA extraction from PFS. The use of either 10% talc or 0.5% dyes completely adsorbed DNA, resulting in negative PCR amplifications. For the first time, pharmaceutical excipients were shown to affect DNA extraction explaining the inability of recovering DNA from some PFS samples in previous studies.This work received financial support from the European Union
(FEDER funds through COMPETE) and National Funds (FCT,
Fundaç~ao para a Ci^encia e Tecnologia) through project EXPL/DTPSAP/
1438/2013 (Safety of plant food supplements: searching for
adulterant pharmaceutical drugs and plants) and UID/QUI/50006/
2013. Joana Costa and Telmo J.R. Fernandes are grateful to FCT
grants SFRH/BPD/102404/2014 and SFRH/BD/93711/2013, respectively,
financed by POPH-QREN (subsidized by FSE and MCTES).This work received financial support from the European Union
(FEDER funds through COMPETE) and National Funds (FCT,
Fundaç~ao para a Ci^encia e Tecnologia) through project EXPL/DTPSAP/
1438/2013 (Safety of plant food supplements: searching for
adulterant pharmaceutical drugs and plants) and UID/QUI/50006/
2013. Joana Costa and Telmo J.R. Fernandes are grateful to FCT
grants SFRH/BPD/102404/2014 and SFRH/BD/93711/2013, respectively,
financed by POPH-QREN (subsidized by FSE and MCTES).info:eu-repo/semantics/publishedVersio
Drosophila motor neuron boutons remodel through membrane blebbing coupled with muscle contraction
Funding Information: We would like to thank Telmo Pereira from the Microscopy Facility for technical support, the Fly Facility at Nova Medical Research; CONGENTO: consortium for genetically tractable organisms. We thank the Developmental Studies Hybridoma Bank, Bloomington Drosophila Stock Center and VDRC for antibodies and fly stocks. This work was supported by PTDC-01778/2022- NeuroDev3D to R.O.T. GEMiNI and PTDC/BIA-COM/0151/2020 to C.S.M and European Research Council H2020-GA 810207-ARPCOMPLEXITY to E.R.G. A.R.F. is supported with a PhD scholarship from Fundação para a Ciência e Tecnologia, Portugal, reference SFRH/BD/144488/2019, and J.P.M. with a reference SFRH/BD/130920/2017. This work also supported by iNOVA4Health (UIDB/04462/2020 and UIDP/04462/2020), and LS4FUTURE (LA/P/0087/2020). Funding Information: We would like to thank Telmo Pereira from the Microscopy Facility for technical support, the Fly Facility at Nova Medical Research; CONGENTO: consortium for genetically tractable organisms. We thank the Developmental Studies Hybridoma Bank, Bloomington Drosophila Stock Center and VDRC for antibodies and fly stocks. This work was supported by PTDC-01778/2022- NeuroDev3D to R.O.T. GEMiNI and PTDC/BIA-COM/0151/2020 to C.S.M and European Research Council H2020-GA 810207-ARPCOMPLEXITY to E.R.G.. A.R.F. is supported with a PhD scholarship from Fundação para a Ciência e Tecnologia, Portugal, reference SFRH/BD/144488/2019, and J.P.M. with a reference SFRH/BD/130920/2017. This work also supported by iNOVA4Health (UIDB/04462/2020 and UIDP/04462/2020), and LS4FUTURE (LA/P/0087/2020). Publisher Copyright: © 2023, The Author(s).Wired neurons form new presynaptic boutons in response to increased synaptic activity, however the mechanism(s) by which this occurs remains uncertain. Drosophila motor neurons (MNs) have clearly discernible boutons that display robust structural plasticity, being therefore an ideal system in which to study activity-dependent bouton genesis. Here, we show that in response to depolarization and in resting conditions, MNs form new boutons by membrane blebbing, a pressure-driven mechanism that occurs in 3-D cell migration, but to our knowledge not previously described to occur in neurons. Accordingly, F-actin is decreased in boutons during outgrowth, and non-muscle myosin-II is dynamically recruited to newly formed boutons. Furthermore, muscle contraction plays a mechanical role, which we hypothesize promotes bouton addition by increasing MN confinement. Overall, we identified a mechanism by which established circuits form new boutons allowing their structural expansion and plasticity, using trans-synaptic physical forces as the main driving force.publishersversionpublishe
Cooperation or conflict? Impact of intraspecific diversity on Escherichia coli biofilms
Intraspecific diversity in biofilm communities is associated with enhanced
survival and growth of the individual biofilm populations. In here, we
assess if this apparent cooperative behavior still holds as the number of
different strains in a biofilm increases. Using E. coli as a model organism,
the influence of intraspecific diversity in biofilm populations composed of
up to six different E. coli strains, was assessed. Biofilm quantification was
evaluated by crystal violet (CV) staining and colony forming units (CFU)
counts. In general, with the increasing number of strains in a biofilm, an
increase in cell counts and a decrease in matrix production was
observed. This observation was confirmed by cluster analysis that
indicated that after 24h of biofilm formation the best model, according to
the Bayesian information criterion (BIC), consisted of three clusters that
grouped together biofilms with an equal number of strains. It hence
appears that increased genotypic diversity in a biofilm leads E. coli to
maximize the production of its offspring, in detriment of the production of
public goods (i.e. matrix components), that would be beneficial to all
strains individually and the consortium as a whole. Apart from the
ecological implications, these results can be explored in the area of
clinical biofilms, as a decrease in matrix production might render these
intraspecies biofilms more sensitive to antimicrobial agents
First stage of the development of an eco-friendly detergent formulation for efficient removal of carbonized soil
Detergent formulations for cleaning a carbonized soil-degreasers-typically comprise surfactants, organic solvents, phosphate-based cleaning agents, and alkaline agents, which results in high pH values (>11) that raise human and environmental risks. It is important to develop eco-friendly and safer degreasers, while maintaining their cleaning efficiency. In this work, simple degreaser formulations, with a pH below 11 and without phosphates, were developed by using a mixture of solvent, surfactant, and water to remove carbonized soil. The efficiency of the new degreaser formulations (with 5 wt% solvent, 5 wt% nonionic or ionic surfactant, and 90 wt% water) was evaluated by an abrasion test in the removal of carbonized soil from ceramic and stainless steel surfaces and compared with a commercial product. The results obtained show that the formulations comprising isopropylene glycol (IPG) with C11-C13 9EOs and diethylene glycol butyl ether (BDG) with octyltrimethylammonium octanoate ([N1118][C8O2]) present the best cleaning efficiency for both surfaces. The composition of these formulations was optimized for each surface using a mixture design. The resulting formulations, despite having a simpler composition, a pH lower than 11, and being phosphate-free, presented a cleaning efficiency equal or slightly higher than the commercial control. These results show that it is possible to design degreasers that are much less aggressive to the environment and user, while simultaneously fulfilling the market requirements.publishe
Integration of Single Cell Traps, Chemical Gradient Generator and Photosensors in a Microfluidic Platform for the Study of Alpha-Synuclein Toxicity in Yeast
AbstractAlpha-synuclein (aSyn) is a key player in Parkinson's disease. Genetically engineered yeast cells producing aSyn fused with GFP (aSyn-GFP) have been used to study this protein. In this work, we present a microfluidic platform with integrated photosensors that captures single yeast cells in arrays of hydrodynamic traps and exposes them to a chemical gradient of precise composition. This platform enables the study of the effects of aSyn expression level and aggregation in genetically modified yeast cells by chemical stimulation. The photosensors allow the detection of cells in the traps by measuring the variations in light transmission or of the fluorescence produced by aSyn-GFP for real-time signal acquisition
Parkinson's Disease and Cognitive-Motor Dual-Task: Is Motor Prioritization Possible in the Early Stages of the Disease?
. The authors aimed to compare the postural phase ofgait initiation under single-task (gait initiation) and dual-task (gaitinitiation plus Stroop test) conditions in healthy subjects and insubjects with Parkinson's disease (PD) in the early stages (Hoehnand Yahr scale .05). Also,no interaction was found between the groups and the conditions(single- and dual-task). Differences were found in the duration ofthe mediolateral postural phase (p D .003), which was higher inPD subjects than in healthy subjects. The findings suggest thatsubjects in the early stages of PD prioritize gait initiation, as theirmotor performance was similar to that of healthy subjects
The influence of a cognitive task on the postural phase of gait initiation in Parkinson's disease: an electromyographic based analysis
The aim of this study was to compare postural control strategies during gait initiation in single- and dual-task conditions in individuals in early stages of Parkinson's Disease (PD). The activation timing of tibialis anterior occurred significantly later in the individuals with PD than in the controls (p =.05), and a significant interaction between the groups, conditions and limbs was found (p =.027). Differences between the single- and dual-task conditions were observed for the activation timing of the tibialis anterior (p =.042) and for the magnitude of soleus (p =.007), with lower values for the dual-task condition. Furthermore, not all the individuals followed the previously reported pattern of soleus inhibition followed by tibialis anterior activation. The duration of the mediolateral displacement of the center of pressure was longer in the individuals with PD than in the controls (p =.019). The anticipatory postural adjustments during gait initiation are impaired in PD and are expressed by an activation failure of tibialis anterior in both single- and dual-task conditions. Hence, it is important that during rehabilitation, intervention should concentrate on the tibialis anterior TA
- …