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7. |
- McMahon, C. R., et al.
(author)
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Animal Borne Ocean Sensors - AniBOS - An Essential Component of the Global Ocean Observing System
- 2021
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In: Frontiers in Marine Science. - : Frontiers Media SA. - 2296-7745. ; 8
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Research review (peer-reviewed)abstract
- Marine animals equipped with biological and physical electronic sensors have produced long-term data streams on key marine environmental variables, hydrography, animal behavior and ecology. These data are an essential component of the Global Ocean Observing System (GOOS). The Animal Borne Ocean Sensors (AniBOS) network aims to coordinate the long-term collection and delivery of marine data streams, providing a complementary capability to other GOOS networks that monitor Essential Ocean Variables (EOVs), essential climate variables (ECVs) and essential biodiversity variables (EBVs). AniBOS augments observations of temperature and salinity within the upper ocean, in areas that are under-sampled, providing information that is urgently needed for an improved understanding of climate and ocean variability and for forecasting. Additionally, measurements of chlorophyll fluorescence and dissolved oxygen concentrations are emerging. The observations AniBOS provides are used widely across the research, modeling and operational oceanographic communities. High latitude, shallow coastal shelves and tropical seas have historically been sampled poorly with traditional observing platforms for many reasons including sea ice presence, limited satellite coverage and logistical costs. Animal-borne sensors are helping to fill that gap by collecting and transmitting in near real time an average of 500 temperature-salinity-depth profiles per animal annually and, when instruments are recovered (similar to 30% of instruments deployed annually, n = 103 +/- 34), up to 1,000 profiles per month in these regions. Increased observations from under-sampled regions greatly improve the accuracy and confidence in estimates of ocean state and improve studies of climate variability by delivering data that refine climate prediction estimates at regional and global scales. The GOOS Observations Coordination Group (OCG) reviews, advises on and coordinates activities across the global ocean observing networks to strengthen the effective implementation of the system. AniBOS was formally recognized in 2020 as a GOOS network. This improves our ability to observe the ocean's structure and animals that live in them more comprehensively, concomitantly improving our understanding of global ocean and climate processes for societal benefit consistent with the UN Sustainability Goals 13 and 14: Climate and Life below Water. Working within the GOOS OCG framework ensures that AniBOS is an essential component of an integrated Global Ocean Observing System.
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8. |
- Mello, D. A. A., et al.
(author)
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Optical Networking With Variable-Code-Rate Transceivers
- 2014
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In: Journal of Lightwave Technology. - 0733-8724 .- 1558-2213. ; 32:2, s. 257-266
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Journal article (peer-reviewed)abstract
- We evaluate the impact of variable-code-rate transceivers on cost, capacity and survivability of wavelength-routed optical networks. The transmission rate and reach trade-off is quantified for two hypothetical coded modulation schemes (aggressive and conservative) in a wavelength routing network with 50-GHz-spaced channels. The aggressive scenario assumes the 64-QAM modulation format, a small gap to capacity, and a small excess bandwidth. The conservative scenario considers the 16-QAM modulation format, and a larger capacity gap and excess bandwidth. The performance of the conservative and aggressive technologies is evaluated in three representative networks. Transparent reaches are calculated by means of an existing analytical method which assumes the AWGN hypothesis for the nonlinear noise. It is shown that variable-code-rate transceivers enable the concept of soft protection, in which the protection lightpath operates at a data rate which is lower than the corresponding working lightpath, in a way to avoid regeneration. This is specially attractive in the transport of IP traffic, where capacity reduction (in average up to 25%) may be tolerable during a repair time. It is also shown that variable-code-rate transceivers have the potential to offer significant savings in terms of transceiver usage and wavelength occupation, when compared to current fixed-rate transceivers operating at 100, 200 or 400 Gb/s. Finally, practical variable-code-rate transceivers may achieve a discrete set of N code rates, yielding a quantized capacity-versus-reach curve. The system impact of N is evaluated for several network scenarios.
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9. |
- Attermeyer, Katrin, et al.
(author)
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Carbon dioxide fluxes increase from day to night across European streams
- 2021
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In: Communications Earth & Environment. - : Springer Nature. - 2662-4435. ; 2:1
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Journal article (peer-reviewed)abstract
- Globally, inland waters emit over 2 Pg of carbon per year as carbon dioxide, of which the majority originates from streams and rivers. Despite the global significance of fluvial carbon dioxide emissions, little is known about their diel dynamics. Here we present a large-scale assessment of day- and night-time carbon dioxide fluxes at the water-air interface across 34 European streams. We directly measured fluxes four times between October 2016 and July 2017 using drifting chambers. Median fluxes are 1.4 and 2.1mmolm(-2) h(-1) at midday and midnight, respectively, with night fluxes exceeding those during the day by 39%. We attribute diel carbon dioxide flux variability mainly to changes in the water partial pressure of carbon dioxide. However, no consistent drivers could be identified across sites. Our findings highlight widespread day-night changes in fluvial carbon dioxide fluxes and suggest that the time of day greatly influences measured carbon dioxide fluxes across European streams. Diel patterns can greatly impact total stream carbon dioxide emissions, with 39% greater carbon dioxide flux during the night-time relative to the day-time, according to a study of 34 streams across Europe.
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- Estienne, A., et al.
(author)
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The endogenous hydrogen sulfide generating system regulates ovulation
- 2019
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In: Free Radical Biology and Medicine. - : Elsevier BV. - 0891-5849. ; 138, s. 43-52
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Journal article (peer-reviewed)abstract
- The generation of free-radicals such as nitric oxide has been implicated in the regulation of ovarian function, including ovulation. Tissues that generate nitric oxide typically generate another free-radical gas, hydrogen sulfide (H2S), although little is known about the role of H2S in ovarian function. The hypothesis of this study was that H2S regulates ovulation. Treatment with luteinizing hormone (LH) increased the levels of mRNA and protein of the H2S generating enzyme cystathionine.-lyase (CTH) in granulosa cells of mice and humans in vivo and in vitro. Pharmacological inhibition of H2S generating enzymes reduced the number of follicles ovulating in mice in vivo and in vitro, and this inhibitory action was reversed by cotreatment with a H2S donor. Addition of a H2S donor to cultured mouse granulosa cells increased basal and LH-dependent abundance of mRNA encoding amphiregulin, betacellulin and tumor necrosis alpha induced protein 6, proteins important for cumulus expansion and follicle rupture. Inhibition of CTH activity reduced abundance of mRNA encoding matrix metalloproteinase-2 and -9 and tissue-type plasminogen activator, and cotreatment with the H2S donor increased the levels of these mRNA above those stimulated by LH alone. We conclude that the H2S generating system plays an important role in the propagation of the preovulatory cascade and rupture of the follicle at ovulation.
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13. |
- Ferreira, Cláudia, et al.
(author)
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eLIFEwithIBD : study protocol for a randomized controlled trial of an online acceptance and commitment therapy and compassion-based intervention in inflammatory bowel disease
- 2024
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In: Frontiers in Psychology. - : Frontiers Media S.A.. - 1664-1078. ; 15
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Journal article (peer-reviewed)abstract
- Background: Inflammatory bowel disease (IBD) entails physical, psychological, and social burden and holds a significant impact on quality of life. Experiential avoidance, cognitive fusion, shame, and self-criticism have been identified as possible therapeutic targets for improving mental health in people with IBD. Traditional face-to-face psychological therapy continues to provide obstacles for patients seeking assistance. Online psychological therapies centered on acceptance, mindfulness, and compassion have been shown to improve psychological distress in other populations.Objective: This paper presents the study protocol of a two-arm Randomized Controlled Trial (RCT) of an ACT and compassion-based, online intervention –eLIFEwithIBD - on the improvement of psychological distress, quality of life, work and social functioning, IBD symptom perception, illness-related shame, psychological flexibility, and self-compassion.Methods: The eLIFEwithIBD intervention is an adaptation of the LIFEwithIBD programme (delivered through an in-person group format) and entails an ACT, mindfulness, and compassion-based intervention designed to be delivered as an e-health tool for people with IBD. This protocol outlines the structure and contents of the eLIFEwithIBD intervention. Participants were recruited by an advertisement on the social media platforms of Portuguese Associations for IBD in January 2022. A psychologist conducted a brief interview with 80 patients who were interested in participating. Fifty-five participants were selected and randomly assigned to one of two conditions [experimental group (eLIFEwithIBD + medical TAU; n = 37) or control group (medical TAU;n = 18)]. Outcome measurement took place at baseline, post-intervention, and 4-month follow-up. All analyses are planned as intent-to-treat (ITT).Results: The eLIFEwithIBD intervention is expected to empower people with IBD by fostering psychological strategies that promote illness adjustment and well-being and prevent subsequent distress. The eLIFEwithIBD aims to gain a novel and better understanding of the role of online contextual behavioral interventions on improving the quality of life and mental health of people with IBD.Clinical Trial Registration: https://classic.clinicaltrials.gov/ct2/show/NCT05405855, NCT05405855.
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15. |
- Lohmander, A., et al.
(author)
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Students take charge of Learning–Using e-learning in Perceptual Assessment in Speech–Language Pathology
- 2020
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In: Scandinavian Journal of Educational Research. - : Routledge. - 0031-3831 .- 1470-1170.
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Journal article (peer-reviewed)abstract
- Perceptual assessment is the basis for diagnosis and evaluation of treatment in speech–language pathology (SLP). Students need to practise assessment skills. A web-based platform with cases and expert feedback in cleft palate disorders was developed in national collaboration. The aim of the study was to evaluate the results of individual training on assessment skills in SLP students and their perception of e-learning. Forty-five students performed tests using a pre- and post-test set-up. Perceptual assessments were demonstrated and instructions provided during teacher-led activities in ongoing fully scheduled courses; students were then individually trained in their free time. Reference samples were available. A significant improvement was found in rating and phonetic transcriptions after training. Positive comments concerned accessibility and practice time.
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- Trindade, Inês, 1990, et al.
(author)
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The LIFEwithIBD Intervention: Study Protocol for a Randomized Controlled Trial of a Face-to-Face Acceptance and Commitment Therapy and Compassion-Based Intervention Tailored to People With Inflammatory Bowel Disease
- 2021
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In: Frontiers in Psychiatry. - : Frontiers Media SA. - 1664-0640. ; 12
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Journal article (peer-reviewed)abstract
- Background: There is ample evidence of the high mental health burden caused by Inflammatory Bowel Disease (IBD). Several constructs such as experiential avoidance, cognitive fusion, shame, and self-criticism have recently emerged as potential intervention targets to improve mental health in IBD. Psychotherapeutic models such as Acceptance and Commitment Therapy and compassion-based interventions are known to target these constructs. In this protocol, we aim to describe a two-arm Randomized Controlled Trial (RCT) testing the efficacy of an ACT and compassion-focused intervention named Living with Intention, Fullness, and Engagement with Inflammatory Bowel Disease (LIFEwithIBD) intervention + Treatment As Usual (TAU) vs. TAU in improving psychological distress, quality of life, work and social functioning, IBD symptom perception, illness-related shame, psychological flexibility, self-compassion, disease activity, inflammation biomarkers, and gut microbiota diversity. Methods: This trial is registered at (Identifier: NCT03840707, date assigned 13/02/2019). The LIFEwithIBD intervention is an adaptation to the IBD population of the Mind programme for people with cancer, an acceptance, mindfulness, and compassion-based intervention designed to be delivered in a group format. The LIFEwithIBD intervention's structure and topics are presented in this protocol. Participants were recruited at the Gastroenterology Service of the Coimbra University Hospital between June and September 2019. Of the 355 patients screened, 61 participants were selected, randomly assigned to one of two conditions [experimental group (LIFEwithIBD + TAU) or control group (TAU)] and completed the baseline assessment. Outcome measurement took place at baseline, post-intervention, 3- and 12-month follow-ups. Discussion: Results from this RCT will support future studies testing the LIFEwithIBD intervention or other acceptance and/or compassion-based interventions for IBD.
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- Albuquerque, Joaquim F. S., et al.
(author)
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Adaptive changes of the enterochromaffin and gastrin cells in the rat gastrointestinal tract following subtotal colectomy
- 2006
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In: Scandinavian Journal of Gastroenterology. - : Informa UK Limited. - 0036-5521 .- 1502-7708. ; 41:8, s. 963-968
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Journal article (peer-reviewed)abstract
- Objective. Colectomized patients often have diarrhoea and increased gastric acid secretion. Although serotonin influences gastrointestinal (GI) motility and secretion, GI serotonin-producing enterochromaffin (EC) cells have not been investigated after colectomy, nor have the antral gastrin cells. The aim of this experimental study was to investigate the GI tract in rats 8 weeks after subtotal colectomy, with particular emphasis on the frequency and distribution of EC and gastrin cells. Material and methods. Immunohistochemical techniques were used to identify the two endocrine cell types. Results. The colectomized animals had diarrhoea. Body-weight was lower and the small intestine shorter in the colectomized animals compared with sham-operated and untreated controls. In the two surgically treated groups, the antral mucosa was thinner and the small intestinal mucosa was thicker compared with that of the untreated rats, whereas the thickness of the rectum of the colectomized rats was increased compared with that of the control groups. In the colectomized animals, the number of EC cells was increased in the small intestine and rectum, whereas the numbers of both EC and gastrin cells were decreased in the antrum. Conclusions. The results indicate that colectomy exerts a significant influence on the GI mucosa and on the endocrine cell systems studied. An increased number of EC cells can result in alterations in motility and secretion, which may be important in the pathogenesis of the diarrhoea that often occurs after colectomy.
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18. |
- Bravo, Andrea G., et al.
(author)
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The interplay between total mercury, methylmercury and dissolved organic matter in fluvial systems : A latitudinal study across Europe
- 2018
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In: Water Research. - : Elsevier. - 0043-1354 .- 1879-2448. ; 144, s. 172-182
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Journal article (peer-reviewed)abstract
- Large-scale studies are needed to identify the drivers of total mercury (THg) and monomethyl-mercury (MeHg) concentrations in aquatic ecosystems. Studies attempting to link dissolved organic matter (DOM) to levels of THg or MeHg are few and geographically constrained. Additionally, stream and river systems have been understudied as compared to lakes. Hence, the aim of this study was to examine the influence of DOM concentration and composition, morphological descriptors, land uses and water chemistry on THg and MeHg concentrations and the percentage of THg as MeHg (%MeHg) in 29 streams across Europe spanning from 41°N to 64°N. THg concentrations (0.06–2.78 ng L−1) were highest in streams characterized by DOM with a high terrestrial soil signature and low nutrient content. MeHg concentrations (7.8–159 pg L−1) varied non-systematically across systems. Relationships between DOM bulk characteristics and THg and MeHg suggest that while soil derived DOM inputs control THg concentrations, autochthonous DOM (aquatically produced) and the availability of electron acceptors for Hg methylating microorganisms (e.g. sulfate) drive %MeHg and potentially MeHg concentration. Overall, these results highlight the large spatial variability in THg and MeHg concentrations at the European scale, and underscore the importance of DOM composition on mercury cycling in fluvial systems.
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19. |
- Bravo, Andrea G., et al.
(author)
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The interplay between total mercury, methylmercury and dissolved organic matter in fluvial systems : A latitudinal study across Europe
- 2018
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In: Water Research. - : Pergamon. - 0043-1354 .- 1879-2448. ; 144, s. 172-182
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Journal article (peer-reviewed)abstract
- Large-scale studies are needed to identify the drivers of total mercury (THg) and monomethyl-mercury (MeHg) concentrations in aquatic ecosystems. Studies attempting to link dissolved organic matter (DOM) to levels of THg or MeHg are few and geographically constrained. Additionally, stream and river systems have been understudied as compared to lakes. Hence, the aim of this study was to examine the influence of DOM concentration and composition, morphological descriptors, land uses and water chemistry on THg and MeHg concentrations and the percentage of THg as MeHg (%MeHg) in 29 streams across Europe spanning from 41°N to 64 °N. THg concentrations (0.06–2.78 ng L−1) were highest in streams characterized by DOM with a high terrestrial soil signature and low nutrient content. MeHg concentrations (7.8–159 pg L−1) varied non-systematically across systems. Relationships between DOM bulk characteristics and THg and MeHg suggest that while soil derived DOM inputs control THg concentrations, autochthonous DOM (aquatically produced) and the availability of electron acceptors for Hg methylating microorganisms (e.g. sulfate) drive %MeHg and potentially MeHg concentration. Overall, these results highlight the large spatial variability in THg and MeHg concentrations at the European scale, and underscore the importance of DOM composition on mercury cycling in fluvial systems.
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20. |
- Buhai, I. Sebastian, et al.
(author)
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RETURNS TO TENURE OR SENIORITY?
- 2014
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In: Econometrica. - 0012-9682 .- 1468-0262. ; 82:2, s. 705-730
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Journal article (peer-reviewed)abstract
- This study documents two empirical facts using matched employer-employee data for Denmark and Portugal. First, workers who are hired last, are the first to leave the firm. Second, workers' wages rise with seniority, where seniority is defined as a worker's tenure relative to the tenure of his colleagues. Controlling for tenure, the probability of a worker leaving the firm decreases with seniority. The increase in expected seniority with tenure explains a large part of the negative duration dependence of the separation hazard. Conditional on ten years of tenure, the wage differential between the 10th and the 90th percentiles of the seniority distribution is 1.1-1.4 percentage points in Denmark and 2.3-3.4 in Portugal.
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- Ferreira, Cláudia, et al.
(author)
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Randomized controlled trial of an Acceptance and Commitment Therapy and compassion-based group intervention for persons with inflammatory bowel disease : the LIFEwithIBD intervention
- 2024
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In: Frontiers in Psychology. - : Frontiers Media S.A.. - 1664-1078. ; 15
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Journal article (peer-reviewed)abstract
- Objectives: This study tested the acceptability and efficacy of an Acceptance and Commitment Therapy and compassion-based intervention (LIFEwithIBD) in people with IBD through a two-arm RCT.Methods: Participants were recruited at the Gastroenterology Department of the Coimbra University Hospital between June and September 2019. Of the 355 patients screened, those who accepted to participate were randomly assigned to one of two conditions: experimental group (LIFEwithIBD; n = 25) or control group (waitlist; n = 29). Participants completed self-report measures at baseline (T0), post-intervention (T1), and 3-month (T2) and 12-month (T3) follow-ups. Intervention acceptability was assessed. Efficacy was examined using intent-to-treat ANCOVA at post-intervention after adjusting for baseline values of depressive, anxiety, and stress symptoms (primary outcomes). Linear mixed models for all longitudinal outcomes were also analysed. Inflammatory and disease biomarkers were determined at T0 and T3.Results: Acceptability results revealed a high level of satisfaction and perceived usefulness regarding the intervention. Both groups experienced a significant decrease in stress symptoms and IBD symptom perception at T1. No significant differences were observed at follow-up for the primary outcomes. The experimental group reported significantly lower Crohn’s disease Symptom severity at T2 than the control group. Post-hoc analyses designed to mitigate floor effects revealed substantial treatment effects for the experimental group regarding anxiety symptoms. No significant differences were observed in clinical biomarkers from T0 to T3.Conclusion: The LIFEwithIBD intervention shows promising, although preliminary, benefits for managing disease activity and reducing anxiety symptoms in IBD patients with high severity of psychological distress.
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24. |
- Garcia-Cisneros, A., et al.
(author)
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Long telomeres are associated with clonality in wild populations of the fissiparous starfish Coscinasterias tenuispina
- 2015
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In: Heredity. - : Springer Science and Business Media LLC. - 0018-067X .- 1365-2540. ; 115:5, s. 437-443
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Journal article (peer-reviewed)abstract
- Telomeres usually shorten during an organism's lifespan and have thus been used as an aging and health marker. When telomeres become sufficiently short, senescence is induced. The most common method of restoring telomere length is via telomerase reverse transcriptase activity, highly expressed during embryogenesis. However, although asexual reproduction from adult tissues has an important role in the life cycles of certain species, its effect on the aging and fitness of wild populations, as well as its implications for the long-term survival of populations with limited genetic variation, is largely unknown. Here we compare relative telomere length of 58 individuals from four populations of the asexually reproducing starfish Coscinasterias tenuispina. Additionally, 12 individuals were used to compare telomere lengths in regenerating and non-regenerating arms, in two different tissues (tube feet and pyloric cecum). The level of clonality was assessed by genotyping the populations based on 12 specific microsatellite loci and relative telomere length was measured via quantitative PCR. The results revealed significantly longer telomeres in Mediterranean populations than Atlantic ones as demonstrated by the Kruskal-Wallis test (K=24.17, significant value: P-value <0.001), with the former also characterized by higher levels of clonality derived from asexual reproduction. Telomeres were furthermore significantly longer in regenerating arms than in non-regenerating arms within individuals (pyloric cecum tissue: Mann-Whitney test, V=299, P-value <10(-6); and tube feet tissue Student's t=2.28, P-value = 0.029). Our study suggests that one of the mechanisms responsible for the long-term somatic maintenance and persistence of clonal populations is telomere elongation.
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- Portela, E., et al.
(author)
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Controls on Dense Shelf Water Formation in Four East Antarctic Polynyas
- 2022
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In: Journal of Geophysical Research: Oceans. - 2169-9275. ; 127:12
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Journal article (peer-reviewed)abstract
- Coastal polynyas are key formation regions for dense shelf water (DSW) that ultimately contributes to the ventilation of the ocean abyss. However, not all polynyas form DSW. We examine how the physiographic setting, water-mass distribution and transformation, water column stratification, and sea-ice production regulate DSW formation in four East Antarctic coastal polynyas. We use a salt budget to estimate the relative contribution of sea-ice production and lateral advection to the monthly change in salinity in each polynya. DSW forms in Mackenzie polynya due to a combination of physical features (shallow water depth and a broad continental shelf) and high sea-ice production. Sea-ice formation begins early (March) in Mackenzie polynya, counteracting fresh advection and establishing a salty mixed layer in autumn that preconditions the water column for deep convection in winter. Sea-ice production is moderate in the other three polynyas, but saline DSW is not formed (a fresh variety is formed in the Barrier polynya). In the Shackleton polynya, brine rejection during winter is insufficient to overcome the very fresh autumn mixed layer. In Vincennes Bay, a strong inflow of modified Circumpolar Deep Water stratifies the water column, hindering deep convection and DSW formation. Our study highlights that DSW formation in a given polynya depends on a complex combination of factors, some of which may be strongly altered under a changing climate, with potentially important consequences for the ventilation of the deep ocean, the global meridional overturning circulation, and the transport of ocean heat to Antarctic ice shelves.
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29. |
- Portela-Gomes, GM, et al.
(author)
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Insulin-like growth factor II in human fetal pancreas and its co-localization with the major islet hormones: comparison with adult pancreas
- 2000
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In: The Journal of endocrinology. - : Bioscientifica. - 0022-0795 .- 1479-6805. ; 165:2, s. 245-251
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Journal article (peer-reviewed)abstract
- Insulin-like growth factor II (IGF-II) appears to play an important role during fetal life in cell growth and differentiation in several organs, including the pancreas. In the present study we investigated the cellular localization of IGF-II in human fetal pancreas at 16, 18 and 22 embryonic weeks and compared it with adult pancreas. Single and double immunofluorescence methods were used to study co-localization of IGF-II with the four major islet hormones - insulin, glucagon, somatostatin, pancreatic polypeptide - and with islet amyloid polypeptide (IAPP). Distinct IGF-II immunoreactive (IR) cells were found in the endocrine, but not in the exocrine, pancreas. The intensity of IGF-II immunoreactivity was more pronounced in the fetal than in the adult pancreas. In fetal pancreas IGF-II immunoreactivity was observed in virtually all insulin-IR cells and in subsets of the glucagon, somatostatin and IAPP cells. In the adult pancreas, IGF-II immunoreactivity was found in insulin/IAPP cells only. Our results suggest a broader effect of IGF-II in fetal endocrine pancreatic cells than in the adult.
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31. |
- Portela-Gomes, GM, et al.
(author)
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PACAP is expressed in secretory granules of insulin and glucagon cells in human and rodent pancreas - Evidence for generation of cAMP compartments uncoupled from hormone release in diabetic islets
- 2003
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In: Regulatory Peptides. - 1873-1686 .- 0167-0115. ; 113, s. 31-
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Journal article (peer-reviewed)abstract
- Pituitary adenylate cyclase-activating polypeptide (PACAP) is an islet neuropeptide with potent insulinotropic action. The current study investigates PACAP expression in normal human and rat pancreatic islets, and whether it is altered in diabetic state. To that end, PACAP immunoreactivity was studied by immunofluorescence methods enhanced by the catalyzed reporter deposition (CARD) technique. Insulin and cyclic adenosine monophosphate (cAMP) generation induced by PACAP were investigated in islets isolated from the spontaneously diabetic Goto-Kakizaki (GK) rat. PACAP immunoreactivity was observed in virtually all insulin and glucagon cells in both species, but not in somatostatin or pancreatic polypeptide (PP) cells; this co-localization pattern was unaltered in diabetic pancreata. In normal human pancreas, PACAP was further localized ultrastructurally to the secretory granules of insulin and glucagon cells. PACAP significantly potentiated glucose-stimulated insulin release in isolated islets of normal but not of GK rats. PACAP failed to enhance cAMP generation in normal islets, but induced similar to 5-folds exaggeration in the diabetic islets. In conclusion, using improved immunocytochemistry techniques and electron microscopy (EM), PACAP was shown to be expressed both in normal and diabetic islet cells and localized to secretory granules of insulin and glucagon cells. Furthermore, the insulinotropic action of PACAP was markedly impaired in diabetic islets in spite of exaggerated cAMP response. (C) 2003 Elsevier Science B.V. All rights reserved.
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33. |
- Trindade, Inês A., 1990-, et al.
(author)
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Measuring structural model invariance across internet-recruited and hospital-recruited IBD patients : Experiential avoidance’s effect on psychopathological symptoms
- 2021
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In: Current Psychology. - : Springer. - 1046-1310 .- 1936-4733. ; 40:7, s. 3459-3466
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Journal article (peer-reviewed)abstract
- Research has questioned whether it is feasible to assess psychosocial variables through web-based recruitment methods. Previous literature on IBD focused exclusively on testing differences on psychosocial scores and did not test the invariance between types of recruitment on the relationships between variables. The aim of the present study is thus to analyse structural invariance between internet-recruited and hospital-recruited groups of IBD patients on a mediation model with theoretical basis on previous studies (experiential avoidance as possible mediator of the association between IBD symptomatology and psychopathology). The internet sample included 137 IBD patients recruited through a patients association, and the hospital sample comprised 66 IBD patients. Structural equation modelling was used; a multiple-group comparison was conducted to examine model invariance between samples. Although the internet sample presented higher levels of experiential avoidance and psychopathological symptoms compared to the hospital sample, the relationships between these variables were invariant across groups. Experiential avoidance partially mediated the impact of IBD symptomatology on levels of stress, anxiety, and depression symptoms in a similar way for online respondents and hospital-recruited patients. This is a new finding that argues for the validity of web-based research methods.
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34. |
- Trindade, Inês A., 1990-, et al.
(author)
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The influence of self-criticism on depression symptoms among ambulatory patients with inflammatory bowel disease
- 2019
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In: Clinical Psychology and Psychotherapy. - : John Wiley & Sons. - 1063-3995 .- 1099-0879. ; 26:6, s. 743-750
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Journal article (peer-reviewed)abstract
- Considering that self-criticism is an important process in the development and maintenance of depression, and taking into account the stigma associated with inflammatory bowel disease (IBD), the present study aimed to analyse whether self-criticism exacerbates the relationships of depression symptoms with IBD symptomatology and chronic illness-related shame. The sample included 53 ambulatory IBD patients (66% females) with ages from 18 to 65. Moderation analyses were conducted using structural equation modelling. Self-criticism exacerbated the associations of depression with IBD symptoms (b = 0.01; standard error [SE] = 0.00; Z = 3.73; P < .001) and illness shame (b = 0.02; SE = 0.01; Z = 2.40; P = .016). For the same level of IBD symptomatology or chronic illness-related shame, those individuals who present more feelings of inadequacy towards the self, experience more symptoms of depression. This exacerbation effect is stronger when IBD symptomatology and chronic illness-related shame are more intense. A high self-critical IBD patient may view the illness and/or symptomatology as a flaw or error that should be self-corrected. Physicians and other health professionals should be attentive to these pathological mechanisms and should attempt to alleviate them. It may be beneficial to refer high self-critical patients to psychological care.
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