3,566 research outputs found
Congenital Adrenal Hyperplasia - The Main Effect of 21-Hydroxylase Deficiency
Congenital adrenal hyperplasia (CAH) consists of a group of autosomal recessive disorders resulting from enzymatic defects in steroidogenesis. More than 95% of CAH cases result from a deficiency of the 21-hydroxylase enzyme, which leads to cortisol deficiency, with or without aldosterone insufficiency, and also an excess of androgen. The clinical spectrum varies from milder symptoms to severe cases settled by the functional impairment of the corresponding pathogenic variant in the CYP21A2 gene. The two major forms of CAH caused by 21-hydroxylase deficiency are the classical form and the non-classic, or late onset form. There are two subtypes of the classic form: salt wasting and simple virilized. Diagnosis is clinically confirmed by 17OH-progesterone measurements, although genotyping is now progressively assuming an essential role for characterising patients. Genotyping is sometimes challenging, due to the existence of the highly homologous CYP21A1P pseudogene. The 21-hydroxylase enzyme is encoded by the CYP21A2 gene, where most of the pathogenic variants defects are due to meiotic recombination phenomena events between the CYP21A2 and CYP21A1P. Complete gene analysis is recommended to obtain a correct diagnosis and a better understanding of the underlying mechanisms of the disease in patients with CAH, and is relevant for prognosis and for prescribing the appropriate type of genetic counselling
Using meta-learning to predict performance metrics in machine learning problems
Machine learning has been facing significant challenges over the last years, much of which stem from the new characteristics of machine learning problems, such as learning from streaming data or incorporating human feedback into existing datasets and models. In these dynamic scenarios, data change over time and models must adapt. However, new data do not necessarily mean new patterns. The main goal of this paper is to devise a method to predict a model's performance metrics before it is trained, in order to decide whether it is worth it to train it or not. That is, will the model hold significantly better results than the current one? To address this issue, we propose the use of meta-learning. Specifically, we evaluate two different meta-models, one built for a specific machine learning problem, and another built based on many different problems, meant to be a generic meta-model, applicable to virtually any problem. In this paper, we focus only on the prediction of the root mean square error (RMSE). Results show that it is possible to accurately predict the RMSE of future models, event in streaming scenarios. Moreover, results also show that it is possible to reduce the need for re-training models between 60% and 98%, depending on the problem and on the threshold used.This work was supported by the Northern Regional Operational Program, Portugal 2020 and European Union, trough European Regional Development Fund (ERDF) in the scope of project number 39900 - 31/SI/2017, and by FCT – Fundação para a Ciência e Tecnologia within projects UIDB/04728/2020 and UIDB/00319/2020
Assessing dental symmetry: introduction of the Symmetry Measure Score (SMS) in periodontal disease analysis
IMS and CEAULinfo:eu-repo/semantics/publishedVersio
Familial combined pituitary hormone deficiency by a mutation in PROP1: 4 of 7 brothers affected
AbstractIntroductionPROP1 (Prophet of POUF1) mutations are the most frequent genetic cause of combined pituitary hormone deficiency, a condition associated with a deficiency or inadequate production of hormones of the anterior pituitary. The PROP1 gene encodes a transcription factor involved in the ontogeny, differentiation and function of somatotrophs, lactotrophs and thyrotrophs. These mutations are characterized by a remarkable clinical variability, including time of onset of hormonal deficiencies, hypophyseal dimensions and secretion of cortisol.Case reportWe describe a family of consanguineous parents (second-degree cousins), composed of 7 siblings, 4 with combined pituitary hormone deficiency. Two brothers, 41 and 45 years of age, had an initial diagnosis of dwarfism at ages 9 and 12 respectively. Subsequently, TSH, FSH/LH and prolactin deficiency was detected in both. The latter was also diagnosed with cortisol deficiency. The two sisters, aged 46 and 50-years-old, were diagnosed with combined pituitary hormone deficiency, namely of GH, TSH, FSH/LH, prolactin and ACTH, since the ages of 15 and 9, respectively. There was no previous family history of combined pituitary hormone deficiency. The genetic study was performed in the 4 brothers, detecting a homozygous mutation in the PROP1 gene (c.301–302delAG).ConclusionThis case reflects the variability of clinical expression and the progressive functional impairment, including pituitary secretion of ACTH, in patients with PROP1 gene mutations
Cellulose Acetate Microbeads for Controlled Delivery of Essential Micronutrients
The controlled delivery
of micronutrients to soil and plants is
essential to increase agricultural yields. However, this is today
achieved using fossil fuel-derived plastic carriers, posing environmental
risks and contributing to global carbon emissions. In this work, a
novel and efficient way to prepare biodegradable zinc-impregnated
cellulose acetate beads for use as controlled release fertilizers
is presented. Cellulose acetate solutions in DMSO were dropped into
aqueous antisolvent solutions of different zinc salts. The droplets
underwent phase inversion, forming solid cellulose acetate beads containing
zinc, as a function of zinc salt type and concentration. Even higher
values of zinc uptake (up to 15.5%) were obtained when zinc acetate
was added to the cellulose acetate–DMSO solution, prior to
dropping in aqueous zinc salt antisolvent solutions. The release profile
in water of the beads prepared using the different solvents was linked
to the properties of the counter-ions via the Hofmeister series. Studies
in soil showed the potential for longer release times, up to 130 days
for zinc sulfate beads. These results, together with the efficient
bead production method, demonstrate the potential of zinc-impregnated
cellulose acetate beads to replace the plastic-based controlled delivery
products used today, contributing to the reduction of carbon emissions
and potential environmental impacts due to the uptake of plastic in
plants and animals
Cellulose Acetate Microbeads for Controlled Delivery of Essential Micronutrients
The controlled delivery of micronutrients to soil and plants is essential to increase agricultural yields. However, this is today achieved using fossil fuel-derived plastic carriers, posing environmental risks and contributing to global carbon emissions. In this work, a novel and efficient way to prepare biodegradable zinc-impregnated cellulose acetate beads for use as controlled release fertilizers is presented. Cellulose acetate solutions in DMSO were dropped into aqueous antisolvent solutions of different zinc salts. The droplets underwent phase inversion, forming solid cellulose acetate beads containing zinc, as a function of zinc salt type and concentration. Even higher values of zinc uptake (up to 15.5%) were obtained when zinc acetate was added to the cellulose acetate-DMSO solution, prior to dropping in aqueous zinc salt antisolvent solutions. The release profile in water of the beads prepared using the different solvents was linked to the properties of the counter-ions via the Hofmeister series. Studies in soil showed the potential for longer release times, up to 130 days for zinc sulfate beads. These results, together with the efficient bead production method, demonstrate the potential of zinc-impregnated cellulose acetate beads to replace the plastic-based controlled delivery products used today, contributing to the reduction of carbon emissions and potential environmental impacts due to the uptake of plastic in plants and animals.</p
Epidemiological, social and economic burden of severe hypoglycaemia in patients with diabetes mellitus in Portugal: a structured literature review
Introduction: The aim of this review was to identify and review studies reporting on the epidemiological, social, and economic impact associated with severe hypoglycemia (SH) in people with diabetes mellitus (DM) in Portugal. Methods: A structured literature search was carried out in PubMed and Embase using a predefined selection criterion. Studies published in either Portuguese or English, between January 2010 and February 2021 were deemed eligible for inclusion. Results: Twelve studies including adults (aged ≥ 18 years) with type 1 and/or type 2 diabetes mellitus (T1DM/T2DM) were eligible for inclusion. Epidemiological estimates varied according to the setting and type of data source used. The proportion of patients who experienced ≥ 1 SH episode (SHE) in the previous 6-12 months varied from 3.1% in adults with T2DM to 36.8% in adults with T1DM. In adults with T2DM, the prevalence in a community-based study was highest in the insulin and secretagogue combination-treated group (9.1%), while in an emergency department setting prevalence was highest in the insulin-based therapy group and the oral hypoglycaemic agent without secretagogues group (32.0% and 20.0%, respectively). The prevalence of SH in other studies of patients with DM ranged from 0.1% (emergency department) to 18.1% (hospital ward). Patients treated with secretagogues had the highest rates of hospitalizations. In patients with T1DM, the annual rate of SHE was higher in those with impaired hypoglycemia awareness than in those with intact awareness. Mean total cost (direct and indirect) per SHE ranged from €1493.00 in patients with T2DM treated in an emergency setting to €2608.51 in patients with T1DM who were hospitalized. Conclusion: Hypoglycaemic events, especially SHE, have a significant effect on the life of persons living with DM and their caregivers. Studies show that the prevalence of this acute complication of diabetes is not negligible. In addition to the negative impact on the quality of life, the burden of SHE in Portugal translates into a significant impact on global health expenditure.info:eu-repo/semantics/publishedVersio
A Structured Literature Review
Funding Information: This work and the journal’s Rapid Service Fee was supported by Eli Lilly and Company. Publisher Copyright: © 2023, The Author(s).Introduction: The aim of this review was to identify and review studies reporting on the epidemiological, social and economic impact associated with severe hypoglycaemia (SH) in people with diabetes mellitus (DM) in Portugal. Methods: A structured literature search was carried out in PubMed and Embase using a predefined selection criterion. Studies published in either Portuguese or English, between January 2010 and February 2021 were deemed eligible for inclusion. Results: Twelve studies including adults (aged ≥ 18 years) with type 1 and/or type 2 diabetes mellitus (T1DM/T2DM) were eligible for inclusion. Epidemiological estimates varied according to the setting and type of data source used. The proportion of patients who experienced ≥ 1 SH episode (SHE) in the previous 6–12 months varied from 3.1% in adults with T2DM to 36.8% in adults with T1DM. In adults with T2DM the prevalence in a community-based study was highest in the insulin and secretagogue combination treated group (9.1%), while in an emergency department setting prevalence was highest in the insulin-based therapy group and the oral hypoglycaemic agent without secretagogues group (32.0% and 20.0%, respectively). The prevalence of SH in other studies in patients with DM ranged from 0.1% (emergency department) to 18.1% (hospital ward). Patients treated with secretagogues had the highest rates of hospitalisations. In patients with T1DM, the annual rate of SHE was higher in those with impaired hypoglycaemia awareness than in those with intact awareness. Mean total cost (direct and indirect) per SHE ranged from €1493.00 in patients with T2DM treated in an emergency setting to €2608.51 in patients with T1DM who were hospitalised. Conclusion: Hypoglycaemic events, especially SHE, have a significant effect on the life of persons living with DM and their caregivers. Studies show that the prevalence of this acute complication of diabetes is not negligible. In addition to the negative impact on the quality of life, the burden of SHE in Portugal translates into a significant impact on the global health expenditure.publishersversionpublishe
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