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1.
BMC Infect Dis ; 24(1): 15, 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-38166687

ABSTRACT

BACKGROUND: Viral hepatitis is a significant health concern among indigenous population in the Americas. In Brazil, reports find high endemicity of HBV and HDV infections has been reported in several indigenous groups. However, few studies have documented the prevalence of HBV, HCV and HDV in the Yanomami. In this study, the prevalence of hepatitis B, C, and D serological markers and potential risk factors were investigated to provide guidance for the development of strategies aimed at reducing viral transmission in the Yanomami indigenous villages. METHODS: This cross-sectional study was carried out in March 2015 and included 430 individuals from four Yanomami villages: Alapusi (n = 78), Castanha/Ahima (n = 126), Gasolina (n = 105), and Taibrapa (n = 121). A rapid test was used for detection of HBsAg and anti-HCV and chemiluminescent immunoassay for anti-HBs, anti-HBc, and anti-HDV antibodies. RESULTS: HBsAg, anti-HBc, and anti-HBs were detected in 8.8, 45.5, and 49.4% of the participants, respectively. The estimated HBV status: current infection 9.6% (38/395); resolved infection 43.3% (171/395); vaccine immunity 20.5% (81/395), and susceptible to HBV 26.6% (105/395). Gasolina presented the lowest prevalence of HBV infection (6.5%) and the highest prevalence of vaccine immunity (26.9%). Children < 15 years old were highly susceptible to infection, as 53.1% did not have antibodies to HBV, while more than 80% of individuals over 45 years of age had been exposed to HBV. The markers for HDV were founded among 12.5% (4/32) of the HBsAg carriers. Anti-HCV was identified in all villages, with the highest prevalence in Alapusi (5.1%). Possible risk factors such as the use of piercings, tattoos, and contact with prospectors showed no statistical difference between the groups. CONCLUSIONS: Viral hepatitis B and serological markers for HCV and HDV were found to be widely distributed among the Yanomami indigenous community, while the prevalence of vaccine immunity to HBV was low. This finding reinforces the importance of promoting systematized diagnostic and vaccination strategies in indigenous communities. Our data confirm that isolated and difficult-to-reach indigenous communities lack appropriate access to diagnosis, treatment, and vaccination.


Subject(s)
Hepatitis B , Hepatitis C , Hepatitis, Viral, Human , Vaccines , Child , Humans , Adolescent , Hepatitis B Surface Antigens , Seroepidemiologic Studies , Cross-Sectional Studies , Hepatitis B/epidemiology , Hepatitis B/diagnosis , Hepatitis B Antibodies , Hepatitis B virus , Hepatitis, Viral, Human/epidemiology , Hepatitis C Antibodies , Prevalence , Hepatitis C/epidemiology
2.
Int J Geriatr Psychiatry ; 39(1): e6056, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38229210

ABSTRACT

OBJECTIVES: We have previously demonstrated difficulties in written production in dementia with Lewy bodies (DLB) patients. We now aim to determine the neural correlates of writing production in DLB, combining clinical data and structural MRI measures. METHOD: Sixteen prodromal to mild DLB patients were selected to participate in the study. The GREMOTS test was used to assess writing production. Using three-dimensional T1 brain MRI images, correlations between the GREMOTS test and grey matter (GM) volume were performed using voxel-based morphometry (VBM; SPM12, XjView and Matlab R2021b softwares). RESULTS: VBM analysis (p < 0.001, uncorrected) revealed a positive and significant correlation between both left anterior insula and left supramarginal gyrus GM volumes and DLB patients' ability to write logatoms using the phonological route. The handwriting deficit was negatively and significantly correlated to the supplementary motor area. The parkinsonism-like characteristics of agraphia were negatively and significantly correlated with both right anterior and right posterior cerebellum GM volumes. Our study also revealed a negative and significant correlation between grammatical spelling impairments and an area of the orbitofrontal gyrus, and a negative and significant correlation between supramarginal gyrus and general slowness in dictation tasks. CONCLUSION: Writing disorders in early DLB patients appears to be GM decreases in several brain regions, such as the left anterior insula, the left supramaginal gyrus, as well as two areas of the right cerebellum.


Subject(s)
Dementia , Lewy Body Disease , Humans , Lewy Body Disease/diagnostic imaging , Brain/diagnostic imaging , Gray Matter/diagnostic imaging , Magnetic Resonance Imaging , Writing
3.
Health Res Policy Syst ; 22(1): 61, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38802932

ABSTRACT

BACKGROUND: Decentralization of a health system is a complex and multidimensional phenomenon that demands thorough investigation of its process logistics, predisposing factors and implementation mechanisms, within the broader socio-political environment of each nation. Despite its wide adoption across both high-income countries (HICs) and low-and-middle-income countries (LMICs), empirical evidence of whether decentralization actually translates into improved health system performance remains inconclusive and controversial. This paper aims to provide a comprehensive description of the decentralization processes in three countries at different stages of their decentralization strategies - Pakistan, Brazil and Portugal. MAIN BODY: This study employed a systematic analysis of peer-reviewed academic journals, official government reports, policy documents and publications from international organizations related to health system decentralization. A comprehensive search was conducted using reputable databases such as PubMed, Google Scholar, the WHO repository and other relevant databases, covering the period up to the knowledge cutoff date in June 2023. Information was systematically extracted and organized into the determinants, process mechanics and challenges encountered during the planning, implementation and post-decentralization phases. Although decentralization reforms have achieved some success, challenges persist in their implementation. Comparing all three countries, it was evident that all three have prioritized health in their decentralization reforms and aimed to enhance local decision-making power. Brazil has made significant progress in implementing decentralization reforms, while Portugal and Pakistan are still in the process. Pakistan has faced significant implementation challenges, including capacity-building, resource allocation, resistance to change and inequity in access to care. Brazil and Portugal have also faced challenges, but to a lesser extent. The extent, progress and challenges in the decentralization processes vary among the three countries, each requiring ongoing evaluation and improvement to achieve the desired outcomes. CONCLUSION: Notable differences exist in the extent of decentralization, the challenges faced during implementation and inequality in access to care between the three countries. It is important for Portugal, Brazil and Pakistan to address these through reinforcing implementation strategies, tackling inequalities in access to care and enhancing monitoring and evaluation mechanism. Additionally, fostering knowledge sharing among these different countries will be instrumental in facilitating mutual learning.


Subject(s)
Delivery of Health Care , Health Care Reform , Health Policy , Politics , Humans , Brazil , Delivery of Health Care/organization & administration , Developing Countries , Health Care Reform/organization & administration , Pakistan , Portugal
4.
BMC Med Educ ; 24(1): 378, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38589877

ABSTRACT

BACKGROUND: When healthcare students witness, engage in, or are involved in an adverse event, it often leads to a second victim experience, impacting their mental well-being and influencing their future professional practice. This study aimed to describe the efforts, methods, and outcomes of interventions to help students in healthcare disciplines cope with the emotional experience of being involved in or witnessing a mistake causing harm to a patient during their clerkships or training. METHODS: This systematic review followed the PRISMA guidelines and includes the synthesis of eighteen studies, published in diverse languages from 2011 to 2023, identified from the databases MEDLINE, EMBASE, SCOPUS and APS PsycInfo. PICO method was used for constructing a research question and formulating eligibility criteria. The selection process was conducted through Rayyan. Titles and abstracts of were independently screened by two authors. The critical appraisal tools of the Joanna Briggs Institute was used to assess the risk of bias of the included studies. RESULTS: A total of 1354 studies were retrieved, 18 met the eligibility criteria. Most studies were conducted in the USA. Various educational interventions along with learning how to prevent mistakes, and resilience training were described. In some cases, this experience contributed to the student personal growth. Psychological support in the aftermath of adverse events was scattered. CONCLUSION: Ensuring healthcare students' resilience should be a fundamental part of their training. Interventions to train them to address the second victim phenomenon during their clerkships are scarce, scattered, and do not yield conclusive results on identifying what is most effective and what is not.

5.
Hum Mol Genet ; 30(9): 771-788, 2021 05 28.
Article in English | MEDLINE | ID: mdl-33693642

ABSTRACT

Down syndrome (DS) is the most common genetic form of intellectual disability caused by the presence of an additional copy of human chromosome 21 (Hsa21). To provide novel insights into genotype-phenotype correlations, we used standardized behavioural tests, magnetic resonance imaging and hippocampal gene expression to screen several DS mouse models for the mouse chromosome 16 region homologous to Hsa21. First, we unravelled several genetic interactions between different regions of chromosome 16 and how they contribute significantly to altering the outcome of the phenotypes in brain cognition, function and structure. Then, in-depth analysis of misregulated expressed genes involved in synaptic dysfunction highlighted six biological cascades centred around DYRK1A, GSK3ß, NPY, SNARE, RHOA and NPAS4. Finally, we provide a novel vision of the existing altered gene-gene crosstalk and molecular mechanisms targeting specific hubs in DS models that should become central to better understanding of DS and improving the development of therapies.


Subject(s)
Down Syndrome , Animals , Basic Helix-Loop-Helix Transcription Factors/metabolism , Cognition , Disease Models, Animal , Down Syndrome/genetics , Down Syndrome/pathology , Hippocampus/metabolism , Mice , Mice, Transgenic
6.
BMC Med ; 21(1): 312, 2023 08 17.
Article in English | MEDLINE | ID: mdl-37592294

ABSTRACT

BACKGROUND: All health overuse implies an unnecessary risk of patients suffering adverse events (AEs). However, this hypothesis has not been corroborated by direct estimates for inappropriate hospital admission (IHA). The objectives of the study were the following: (1) to analyze the association between IHA and the development of subsequent AEs; (2) to explore the distinct clinical and economic implications of AEs subsequent IHA compared to appropriate admissions. METHODS: An observational cross-sectional study was conducted on hospitalized patients in May 2019 in a high-complexity hospital in Madrid, Spain. The Appropriateness Evaluation Protocol was used to measure IHA, and the methodologies of the Harvard Medical Practice Study and the European Point Prevalence Survey of Healthcare-associated Infections were used to detect and characterize AEs. The association between IHA and the subsequent. RESULTS: A total of 558 patients in the hospital ward were studied. IHA increased the risk of subsequent occurrence of AEs (OR [95% CI]: 3.54 [1.87 to 6.69], versus appropriate) and doubled the mean AEs per patient (coefficient [95% CI]: 0.19 [0.08 to 0.30] increase, versus appropriate) after adjusting for confounders. IHA was a predictive variable of subsequent AEs and the number of AEs per patient. AEs developed after IHA were associated with scheduled admissions (78.9% of AEs, versus 27.9% after appropriate admissions; p < 0.001). Compared with AEs developed after appropriate admissions, AEs after IHA added 2.4 additional days of stay in the intensive care unit and incurred an extra cost of €166,324.9 for the studied sample. CONCLUSIONS: Patients with IHA have a higher risk of subsequent occurrence of AE. Due to the multifactorial nature of AEs, IHA is a possible contributing factor. AEs developed after IHA are associated with scheduled admissions, prolonged ICU stays, and resulted in significant cost overruns.


Subject(s)
Cross Infection , Hospitalization , Humans , Cross-Sectional Studies , Risk Factors , Hospitals
7.
Med Mycol ; 61(11)2023 Nov 06.
Article in English | MEDLINE | ID: mdl-37947253

ABSTRACT

Vulvovaginal candidiasis (VVC) is a fungal infection caused mainly by Candida albicans. The treatment of VVC with azoles has been impaired due to the increased cases of resistance presented by this pathogen. The aim of the present study was to investigate the antifungal activity of mucoadhesive chitosan nanoparticles encapsulating both green propolis and fluconazole for topical use in the treatment of VVC. The nanoparticles were prepared by the ionic gelation method, resulting in a size of 316.5 nm containing 22 mg/kg of green propolis and 2.4 mg/kg of fluconazole. The nanoparticles were non-toxic in vitro using red blood cells or in vivo in a Galleria mellonella toxicity model. The treatment of female BALB/c mice infected by C. albicans ATCC 10231 with topical nanoparticles co-encapsulating fluconazole and green propolis was effective even using a fluconazole amount 20 times lower than the amount of miconazole nitrate 2% cream. Considering that the mucoadhesive property of chitosan, which is known to allow a prolonged retention time of the compounds at the mucous epithelia, the antifungal potential of the phenols and flavonoids present in green propolis may have favored the effectiveness of this treatment. These results indicate that this formulation of topical use for fluconazole associated with green propolis can be used as a promising approach to therapy for the treatment of VVC, thus contributing to reducing the development of resistance to azoles.


Vulvovaginal candidiasis is a fungal infection for which we search for alternatives for its treatment. Thus, a nanoparticle formulation based on fluconazole and green propolis was developed. These nanoparticles were tested, and we obtained adequate results in laboratory tests.


Subject(s)
Candidiasis, Vulvovaginal , Chitosan , Nanoparticles , Propolis , Female , Animals , Mice , Fluconazole/therapeutic use , Candidiasis, Vulvovaginal/drug therapy , Candidiasis, Vulvovaginal/microbiology , Candidiasis, Vulvovaginal/veterinary , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Propolis/therapeutic use , Disease Models, Animal , Candida albicans , Microbial Sensitivity Tests/veterinary
8.
Br J Nutr ; 130(12): 2198-2205, 2023 12 28.
Article in English | MEDLINE | ID: mdl-37466032

ABSTRACT

Although studies show that the intake of ultra-processed products (UPP) has a negative impact on health, diet quality and dietary vitamin D, its influence on serum concentrations of this vitamin remains unknown; therefore, it is essential to verify the association between the UPP consumption and vitamin D deficiency. This is a cross-sectional, household, population-based study, carried out with 229 individuals aged 20 years or older, residents of the city of Teresina, Piauí, Brazil. Socio-demographic, lifestyle, food consumption and anthropometric data were collected. Food consumption was obtained using a 24-h food recall, and foods were grouped according to the NOVA classification. Plasma concentrations of calcidiol-25 (OH) D3 were determined by HPLC. Crude and adjusted binary logistic regression was applied to estimate the association between UPP consumption and vitamin D deficiency. Most individuals aged 20-39 years were vitamin D deficient (52·1 %). UPP contributed 19·9 % to the energetic intake of the participant's diet. This contribution was higher for individuals with vitamin D deficiency (22·5 %, P = 0·04). In addition, a high intake of UPP was associated with twice the risk of vitamin D deficiency in comparison with low consumption of UPP (OR: 2·05; CI 1·06, 4·50; P: 0·04). Our results suggest that the consumption of UPP may have a negative impact on serum concentrations of vitamin D; more studies are needed.


Subject(s)
Energy Intake , Vitamin D Deficiency , Adult , Aged , Humans , Brazil/epidemiology , Cross-Sectional Studies , Fast Foods , Diet , Vitamins , Vitamin D Deficiency/epidemiology , Vitamin D , Food Handling
9.
Sensors (Basel) ; 23(2)2023 Jan 05.
Article in English | MEDLINE | ID: mdl-36679400

ABSTRACT

Biofouling is the major factor that limits long-term monitoring studies with automated optical instruments. Protection of the sensing areas, surfaces, and structural housing of the sensors must be considered to deliver reliable data without the need for cleaning or maintenance. In this work, we present the design and field validation of different techniques for biofouling protection based on different housing materials, biocides, and transparent coatings. Six optical turbidity probes were built using polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), PLA with copper filament, ABS coated with PDMS, ABS coated with epoxy and ABS assembled with a system for in situ chlorine production. The probes were deployed in the sea for 48 days and their anti-biofouling efficiency was evaluated using the results of the field experiment, visual inspections, and calibration signal loss after the tests. The PLA and ABS were used as samplers without fouling protection. The probe with chlorine production outperformed the other techniques, providing reliable data during the in situ experiment. The copper probe had lower performance but still retarded the biological growth. The techniques based on transparent coatings, epoxy, and PDMS did not prevent biofilm formation and suffered mostly from micro-biofouling.


Subject(s)
Biofouling , Disinfectants , Biofilms , Chlorine , Copper/chemistry , Biofouling/prevention & control , Chlorides
10.
Molecules ; 28(13)2023 Jun 24.
Article in English | MEDLINE | ID: mdl-37446635

ABSTRACT

Caffeic acid (CA) exhibits a myriad of biological activities including cardioprotective action, antioxidant, antitumor, anti-inflammatory, and antimicrobial properties. On the other hand, CA presents low water solubility and poor bioavailability, which have limited its use for therapeutic applications. The objective of this study was to develop a nanohybrid of zinc basic salts (ZBS) and chitosan (Ch) containing CA (ZBS-CA/Ch) and evaluate its anti-edematogenic and antioxidant activity in dextran and carrageenan-induced paw edema model. The samples were obtained by coprecipitation method and characterized by X-ray diffraction, Fourier transform infrared (FT-IR), scanning electron microscope (SEM) and UV-visible spectroscopy. The release of caffeate anions from ZBS-CA and ZBS-CA/Ch is pH-dependent and is explained by a pseudo-second order kinetics model, with a linear correlation coefficient of R2 ≥ 0.99 at pH 4.8 and 7.4. The in vivo pharmacological assays showed excellent anti-edematogenic and antioxidant action of the ZBS-CA/Ch nanoparticle with slowly releases of caffeate anions in the tissue, leading to a prolongation of CA-induced anti-edematogenic and anti-inflammatory activities, as well as improving its inhibition or sequestration antioxidant action toward reactive species. Overall, this study highlighted the importance of ZBS-CA/Ch as an optimal drug carrier.


Subject(s)
Chitosan , Humans , Chitosan/chemistry , Delayed-Action Preparations/chemistry , Spectroscopy, Fourier Transform Infrared , Antioxidants/pharmacology , Anti-Inflammatory Agents/pharmacology , Edema/pathology , Zinc/chemistry
11.
Int J Prod Econ ; 257: 108782, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36687333

ABSTRACT

The COVID-19 pandemic has brought negative impacts to global supply chains, in particular to the agricultural sector. Although these companies have been developing programs to mitigate the impacts caused by COVID-19, researchers have been worried about a possible weakening of the adoption of sustainable initiatives due to a focus on dealing with the consequences of the pandemic. Grounded on the Resource Orchestration Theory, the goal of this study was to assess the effects of the COVID-19 outbreak on sustainable (environmental, social, and economic) performance in the context of agri-food supply chains. To do so, a questionnaire survey was used to collect data from 349 different medium and large agri-food companies in Brazil. Data were analyzed using Structural Equation Modeling-Partial Least Squares technique. This study has found out that, under the impacts arising from COVID-19 pandemic (1) supply management and transportation and logistics management had a positive impact on food supply chains' sustainable performance; (2) the effects of relationship management and supply chain wide impact management were found to be negative on sustainable performance; and (3) the effects of demand and production management on sustainable performance were not considered significant. We propose a framework that clearly represents the relationship between the disrupted supply chain areas and sustainable performance through the development of orchestration capabilities. By knowing which kinds of impacts produce the most significant effects on sustainable performance, policy makers and managers will be able to make decisions and take actions to avoid negative effects and to improve firms' sustainable performance.

12.
Eur J Neurosci ; 55(2): 611-623, 2022 01.
Article in English | MEDLINE | ID: mdl-34888964

ABSTRACT

Dementia with Lewy bodies (DLB) patients show few significant macroscopic structural changes, especially at the early stages of the disease, making quantitative MRI especially interesting to explore more subtle changes that are not detectable by conventional volumetric techniques. Microstructural alterations have been reported in DLB at the dementia stage, but no study to date was conducted in prodromal patients. Here, quantitative MRI data were collected from 46 DLB prodromal patients and 20 healthy elderly subjects, who also underwent a detailed clinical examination including the Mayo Clinic Fluctuation Scale. We conducted voxel-wise between-group comparisons in diffusion tensor imaging (DTI) metrics and in R2* mapping, along with a multivariate analysis combining the two modalities. We highlighted multiple grey matter and white matter microstructural changes in DLB patients at the prodromal stage, compared to control subjects. Our multivariate analysis identified three distinct regional patterns of DTI and R2* changes (anterior, anteromedial, posterior) in DLB patients, that could reflect different neuropathological processes across brain regions. We also observed an association between R2* alterations in the thalamus, and the severity of fluctuations, in the DLB group. These preliminary findings are promising and require future investigations to better understand the biological underpinnings of microstructural alterations.


Subject(s)
Alzheimer Disease , Lewy Body Disease , Aged , Aging , Alzheimer Disease/pathology , Diffusion Tensor Imaging/methods , Humans , Lewy Body Disease/diagnostic imaging , Lewy Body Disease/pathology , Magnetic Resonance Imaging/methods
13.
J Hepatol ; 77(5): 1276-1286, 2022 11.
Article in English | MEDLINE | ID: mdl-35716846

ABSTRACT

BACKGROUND & AIMS: With or without antiviral treatment, few individuals achieve sustained functional cure of chronic hepatitis B virus (HBV) infection. A better definition of what mediates functional cure is essential for improving immunotherapeutic strategies. We aimed to compare HBV-specific T cell responses in patients with different degrees of viral control. METHODS: We obtained blood from 124 HBV-infected individuals, including those with acute self-limiting HBV infection, chronic infection, and chronic infection with functional cure. We screened for HBV-specific T cell specificities by ELISpot, assessed the function of HBV-specific T cells using intracellular cytokine staining, and characterized HBV-specific CD4 T cells using human leukocyte antigen (HLA) class II tetramer staining, all directly ex vivo. RESULTS: ELISpot screening readily identified HBV-specific CD4 and CD8 T cell responses in acute resolving infection compared with more limited reactivity in chronic infection. Applying more sensitive assays revealed higher frequencies of functional HBV-specific CD4 T cells, but not CD8 T cells, in functional cure compared to chronic infection. Function independent analysis using HLA multimers also identified more HBV-specific CD4 T cell responses in functional cure compared to chronic infection, with the emergence of CD4 T cell memory both after acute and chronic infection. CONCLUSIONS: Functional cure is associated with higher frequencies of functional HBV-specific CD4 memory T cell responses. Thus, immunotherapeutic approaches designed to induce HBV functional cure should also aim to improve CD4 T cell responses. LAY SUMMARY: Immunotherapy is a form of treatment that relies on harnessing the power of an individual's immune system to target a specific disease or pathogen. Such approaches are being developed for patients with chronic HBV infection, in an attempt to mimic the immune response in patients who control HBV infection spontaneously, achieving a so-called functional cure. However, what exactly defines protective immune responses remains unclear. Herein, we show that functional cure is associated with robust responses by HBV-specific CD4 T cells (a type of immune cell).


Subject(s)
Hepatitis B, Chronic , Hepatitis B , Antigens, Surface/therapeutic use , Antiviral Agents/therapeutic use , CD4-Positive T-Lymphocytes , CD8-Positive T-Lymphocytes , Cytokines , Hepatitis B/drug therapy , Hepatitis B virus , Hepatitis B, Chronic/drug therapy , Humans
14.
Trends Food Sci Technol ; 122: 104-109, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35039714

ABSTRACT

BACKGROUND: Recently, anosmia and ageusia (and their variations) have been reported as frequent symptoms of COVID-19. Olfactory and gustatory stimuli are essential in the perception and pleasure of eating. Disorders in sensory perception may influence appetite and the intake of necessary nutrients when recovering from COVID-19. In this short commentary, taste and smell disorders were reported and correlated for the first time with food science. SCOPE AND APPROACH: The objective of this short commentary is to report that taste and smell disorders resulted from COVID-19 may impact eating pleasure and nutrition. It also points out important technologies and trends that can be considered and improved in future studies. KEY FINDINGS AND CONCLUSIONS: Firmer food textures can stimulate the trigeminal nerve, and more vibrant colors are able to increase the modulation of brain metabolism, stimulating pleasure. Allied to this, encapsulation technology enables the production of new food formulations, producing agonist and antagonist agents to trigger or block specific sensations. Therefore, opportunities and innovations in the food industry are wide and multidisciplinary discussions are needed.

15.
Magn Reson Med ; 85(1): 369-379, 2021 01.
Article in English | MEDLINE | ID: mdl-32767495

ABSTRACT

PURPOSE: To determine optimal constrained tissue parameters and off-resonance sequence parameters for single-point macromolecular proton fraction (SP-MPF) mapping based on a comprehensive quantitative magnetization transfer (qMT) protocol in healthy and demyelinated living mice at 7T. METHODS: Using 3D spoiled gradient echo-based sequences, a comprehensive qMT protocol is performed by sampling the Z-spectrum of mice brains, in vivo. Provided additional T1 , B1+ and B0 maps allow for the estimation of qMT tissue parameters, among which three will be constrained, namely the longitudinal and transverse relaxation characteristics of the free pool (R1,f T2,f ), the cross-relaxation rate (R) and the bound pool transverse relaxation time (T2,r ). Different sets of constrained parameters are investigated to reduce the bias between the SP-MPF and its reference based on the comprehensive protocol. RESULTS: Based on a whole-brain histogram analysis about the constrained parameters, the optimal experimental parameters that minimize the global bias between reference and SP-MPF maps consist of a 600° and 6 kHz off-resonance irradiation pulse. Following a Bland-Altman analysis over regions of interest, optimal constrained parameters were R1,f T2,f  = 0.0129, R = 26.5 s-1 , and T2,r  = 9.1 µs, yielding an overall MPF bias of 10-4 (limits of agreement [-0.0068;0.0070]) and a relative variation of 0.64% ± 5.95% between the reference and the optimal single-point method across all mice. CONCLUSION: The necessity of estimating animal model- and field-dependent constrained parameters was demonstrated. The single-point MPF method can be reliably applied at 7T, as part of routine preclinical in vivo imaging protocol in mice.


Subject(s)
Magnetic Resonance Imaging , Protons , Animals , Brain/diagnostic imaging , Brain/metabolism , Brain Mapping , Macromolecular Substances/metabolism , Mesothelin , Mice
16.
J Evol Biol ; 34(6): 910-923, 2021 06.
Article in English | MEDLINE | ID: mdl-33484040

ABSTRACT

Climate change is impacting locally adapted species such as the keystone tree species cork oak (Quercus suber L.). Quantifying the importance of environmental variables in explaining the species distribution can help build resilient populations in restoration projects and design forest management strategies. Using landscape genomics, we investigated the population structure and ecological adaptation of this tree species across the Mediterranean Basin. We applied genotyping by sequencing and derived 2,583 single nucleotide polymorphism markers genotyped from 81 individuals across 17 sites in the studied region. We implemented an approach based on the nearest neighbour haplotype 'coancestry' and uncovered a weak population structure along an east-west climatic gradient across the Mediterranean region. We identified genomic regions potentially involved in local adaptation and predicted differences in the genetic composition across the landscape under current and future climates. Variants associated with temperature and precipitation variables were detected, and we applied a nonlinear multivariate association method, gradient forest, to project these gene-environment relationships across space. The model allowed the identification of geographic areas within the western Mediterranean region most sensitive to climate change: south-western Iberia and northern Morocco. Our findings provide a preliminary assessment towards a potential management strategy for the conservation of cork oak in the Mediterranean Basin.


Subject(s)
Adaptation, Biological , Climate Change , Quercus , Ecosystem , Gene-Environment Interaction , Mediterranean Region , Models, Statistical , Polymorphism, Single Nucleotide
17.
Int J Geriatr Psychiatry ; 36(6): 851-857, 2021 06.
Article in English | MEDLINE | ID: mdl-33300151

ABSTRACT

OBJECTIVES: To determine the prevalence, localization and associations of cerebral microbleeds (CMB) in dementia with Lewy bodies (DLB) with its core clinical symptoms and cerebrospinal fluid (CSF) biomarkers of Alzheimer's disease (AD). We hypothesize DLB patients with CMB have increased amyloid burden compared to those without CMB, which could also translate into clinical differences. METHODS: Retrospective cross-sectional analysis from the AlphaLewyMA study (https://clinicaltrials.gov/ct2/show/NCT01876459). Patients underwent a standardized protocol of brain MRI including 3D T1, 3D FLAIR and T2* sequences, and CSF analysis of AD biomarkers. CMB and white matter hyperintensities (WMHs) were visually assessed in prodromal and mild demented (DLB, N = 91) and AD (AD, N = 67) patients. RESULTS: CMB prevalence did not differ among DLB and AD (24.2% vs. 37.3%; p = 0.081). CMB were mainly distributed in lobar topographies in both DLB (74%) and AD (89%). CMB in DLB was not associated with global cognitive performance, executive functioning, speed of information processing, or AD CSF biomarkers. Similarly, there was no difference regarding specific clinical symptoms: fluctuations, psychotic phenomena, sleep behavior disorder and Parkinsonism between DLB patients with and without CMB. AD patients with CMB had increased burden of WMH compared to those without (2.1 ± 0.86 vs. 1.4 ± 0.89; p = 0.005), according to Fazekas scale, whereas no significant difference was observed in DLB patients (1.68 ± 0.95 vs. 1.42 ± 0.91; p = 0.25). CONCLUSION: CMB were equally prevalent with similar topographic distribution in both DLB and AD patients. CMB was not associated with CSF AD biomarkers or core clinical symptoms in DLB.


Subject(s)
Alzheimer Disease , Lewy Body Disease , Amyloid beta-Peptides , Biomarkers , Cerebral Hemorrhage , Cross-Sectional Studies , Humans , Peptide Fragments , Retrospective Studies
18.
Retina ; 41(2): 366-372, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-32355124

ABSTRACT

PURPOSE: To compare the retinal vasculature characteristics between eyes of patients with and without phacomatosis. METHODS: Case-control observational study with retinal vasculature evaluation by optical coherence tomography and optical coherence tomography angiography of the macula and disk. RESULTS: The study included 80 eyes. Neurofibromatosis Type 1 patients presented with a higher central macular thickness (P = 0.007), a lower optical disk nervous fiber layer (P = 0.006), a lower perimeter, area, and circularity of the foveal avascular zone (P < 0.05), a higher vascular density of macular avascular layer (AMVD) (P = 0.004), and a lower papillary vascular density of superficial capillary plexus (SPVD) (P = 0.048). Patients with tuberous sclerosis presented with an increase in central macular thickness (P = 0.024) and in vascular densities (P < 0.05) [except for macular vascular density of deep capillary plexus (PMVD), AMVD, and SPVD]. Patients with Sturge-Weber syndrome showed a decrease in optical disk nervous fiber layer (P < 0.001), subfoveal choroid thickness (P = 0.011), macular vascular density of superficial capillary plexus (SMVD) (P = 0.036), and SPVD (P < 0.001). CONCLUSION: Phacomatosis patients showed statistically significant differences of retinal vasculature characteristics, compared to eyes without pathology. Further studies are needed to determine when and if these parameters change with the course of the disease and if they can be used as biomarkers for disease severity or progression.


Subject(s)
Fluorescein Angiography/methods , Macula Lutea/pathology , Neurocutaneous Syndromes/diagnosis , Retinal Vessels/pathology , Tomography, Optical Coherence/methods , Visual Acuity , Adolescent , Adult , Aged , Child , Female , Follow-Up Studies , Fundus Oculi , Humans , Male , Middle Aged , Retrospective Studies , Young Adult
19.
BMC Public Health ; 21(1): 1054, 2021 06 02.
Article in English | MEDLINE | ID: mdl-34078348

ABSTRACT

BACKGROUND: The impact of the COVID-19 pandemic has been measured in different metrics, mostly by counting deaths and its impact on health services. Few studies have attempted to calculate years of life lost (YLL) to COVID-19 and compare it with YLL due to other causes in different countries. METHODS: We calculated YLL to COVID-19 from week10 to week52 in 2020 for eight European countries by methods defined by the WHO. We calculated excess YLL by subtracting the average YLL from 2017 to 2019 to the YLL in 2020. Our analysis compared YLL to COVID-19 and the excess YLL of non-COVID-19 causes across countries in Europe. RESULTS: Portugal registered 394,573 cases and 6619 deaths due to COVID-19, accounting for 25,395 YLL in just 10 months. COVID-19 was responsible for 6.7% of all deaths but accounted for only 4.2% of all YLL. We estimate that Portugal experienced an excess of 35,510 YLL (+ 6.2%), of which 72% would have been due to COVID-19 and 28% due to non-COVID-19 causes. Spain, Portugal, and the Netherlands experienced excess YLL to non-COVID-19 causes. We also estimated that Portugal experienced an excess of 10,115 YLL due to cancer (3805), cardiovascular diseases (786) and diseases of the respiratory system (525). CONCLUSION: COVID-19 has had a major impact on mortality rates in Portugal, as well as in other European countries. The relative impact of COVID-19 on the number of deaths has been greater than on the number of YLL, because COVID-19 deaths occur mostly in advanced ages.


Subject(s)
COVID-19 , Pandemics , Europe/epidemiology , Humans , Netherlands , Portugal/epidemiology , SARS-CoV-2 , Spain
20.
Euro Surveill ; 26(33)2021 Aug.
Article in English | MEDLINE | ID: mdl-34414882

ABSTRACT

BackgroundDeterminants of hospitalisation, intensive care unit (ICU) admission and death are still unclear for COVID-19. Few studies have adjusted for confounding for different clinical outcomes including all reported cases within a country.AimWe used routine surveillance data from Portugal to identify risk factors for severe COVID-19 outcomes, and to support risk stratification, public health interventions, and planning of healthcare resources.MethodsWe conducted a retrospective cohort study including 20,293 laboratory-confirmed cases of COVID-19 reported between 1 March and 28 April 2020 through the national epidemiological surveillance system. We calculated absolute risk, relative risk (RR) and adjusted relative risk (aRR) to identify demographic and clinical factors associated with hospitalisation, ICU admission and death using Poisson regressions.ResultsIncreasing age (≥ 60 years) was the major determinant for all outcomes. Age ≥ 90 years was the strongest determinant of hospital admission (aRR: 6.1), and 70-79 years for ICU (aRR: 10.4). Comorbidities of cardiovascular, immunodeficiency, kidney and lung disease (aRR: 4.3, 2.8, 2.4, 2.0, respectively) had stronger associations with ICU admission, while for death they were kidney, cardiovascular and chronic neurological disease (aRR: 2.9, 2.6, 2.0).ConclusionsOlder age was the strongest risk factor for all severe outcomes. These findings from the early stages of the COVID-19 pandemic support risk-stratified public health measures that should prioritise protecting older people. Epidemiological scenarios and clinical guidelines should consider this, even though under-ascertainment should also be considered.


Subject(s)
COVID-19 , Aged , Aged, 80 and over , Hospitalization , Humans , Intensive Care Units , Middle Aged , Pandemics , Portugal/epidemiology , Retrospective Studies , Risk Factors , SARS-CoV-2
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