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1.
Cureus ; 16(6): e63482, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38952594

RESUMEN

Although myopia is a growing global concern, comprehensive studies on its prevalence among Latin American (LATAM) children and adolescents are still lacking. Thus, we conducted a systematic review and meta-analysis to determine the prevalence of myopia in LATAM children and adolescents aged three to 20. The study conducted a thorough literature search from January 1, 1975, to February 28, 2023, identifying 24 studies on the prevalence of myopia in LATAM that met the inclusion criteria. Quality assessment and standardized data collection were performed. The meta-analysis used a random-effects model due to heterogeneity and calculated prevalence rates. Finally, the analysis of data from 24 eligible studies revealed a myopia prevalence of 8.61% (range 0.80-47.36%, 95% confidence interval (CI): 5.22-13.87%, p < 0.05) among 165,721 LATAM children and adolescents. No significant age-based associations or temporal trends were observed in this study. Studies with non-cycloplegic or objective assessment exhibited a numerically higher, although statistically non-significant, myopia prevalence (10.62%, 95% CI: 4.9-21.6%) compared to studies using cycloplegia (7.17%, 95% CI: 3.40-14.50%). In conclusion, myopia affects approximately one in 11 LATAM children and adolescents. Given the increasing exposure of LATAM youth to known myopia risk factors, such as extensive near-work, online learning, and limited outdoor activities, it is crucial to monitor myopia trends in this region. Further research is imperative to address and prevent myopia in LATAM.

2.
bioRxiv ; 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38895230

RESUMEN

Identifying cell types and states remains a time-consuming and error-prone challenge for spatial biology. While deep learning is increasingly used, it is difficult to generalize due to variability at the level of cells, neighborhoods, and niches in health and disease. To address this, we developed TACIT, an unsupervised algorithm for cell annotation using predefined signatures that operates without training data, using unbiased thresholding to distinguish positive cells from background, focusing on relevant markers to identify ambiguous cells in multiomic assays. Using five datasets (5,000,000-cells; 51-cell types) from three niches (brain, intestine, gland), TACIT outperformed existing unsupervised methods in accuracy and scalability. Integration of TACIT-identified cell with a novel Shiny app revealed new phenotypes in two inflammatory gland diseases. Finally, using combined spatial transcriptomics and proteomics, we discover under- and overrepresented immune cell types and states in regions of interest, suggesting multimodality is essential for translating spatial biology to clinical applications.

3.
mBio ; : e0099524, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38832792

RESUMEN

Leishmania (L.) infantum is one of the main causative agents of animal and human leishmaniasis across many endemic areas in South America, Europe, North Africa, and Asia. Despite its clinical significance, little is known about the genetic diversity of L. infantum circulating in a given endemic area. Here, we investigate this important open question by applying a comparative genomics approach to seven L. infantum isolates from different hosts and Italian regions, including the northern part of the country (Emilia-Romagna, RER), Sicily, and Sardinia, as an initial attempt to explore the breadth of parasite genetic heterogeneity in Italy. Additionally, microsatellite analysis was carried out to compare the isolates from RER with other 70 L. infantum strains from the same region as well as 65 strains belonging to the L. donovani complex from other countries. We revealed important karyotypic instability and identified strain-specific changes in gene dosage, which affected important virulence factors such as amastins and surface antigen-like proteins. Single nucleotide polymorphism-based clustering analysis of these genomes together with over 80 publicly available L. infantum and L. donovani genomes placed the Italian isolates into three geographically distinct clusters within the Mediterranean basin and uncovered three isolates clustering with putative L. infantum/L. donovani hybrids isolated in Cyprus. As judged by microsatellite profiling, these hybrid isolates are representative of a sub-population of parasites circulating in northern Italy that preferentially infect humans but not dogs. Our results place Italy at the crossroads of L. infantum infection in the Mediterranean and call attention to the public health risk represented by the introduction of non-European Leishmania species.IMPORTANCEThis study closes important knowledge gaps with respect to Leishmania (L.) infantum genetic heterogeneity in a given endemic country, as exemplified here for Italy, and reveals genetic hybridization as a main cause for re-emerging human leishmaniasis in northern Italy. The observed high diversity of Leishmania parasites on the Italian peninsula suggests different geographical origins, with genomic adaptation to various ecologies affecting both pathogenicity and transmission potential. This is documented by the discovery of a putative L. infantum/L. donovani hybrid strain, which has been shown to preferentially infect humans but not dogs. Our results provide important information to health authorities, which need to consider the public health risk represented by the introduction of new Leishmania species into EU countries due to population displacement or travel from countries where exotic/allochthonous parasite species are endemic.

4.
J Fish Biol ; 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38757464

RESUMEN

Phylogenetic analyses of mitochondrial and nuclear data of 31 specimens of Cyphocharax from trans-Andean rivers support the presence of one lineage of Cyphocharax aspilos in Lago Maracaibo and three cryptic lineages of Cyphocharax magdalenae: (1) Cauca-Magdalena and Ranchería, (2) León and Atrato, and (3) Chucunaque-Tuira, Santa María, and Chiriquí basins of Central America. Results suggest that the Serranía del Perijá facilitated Late Miocene cladogenetic events, whereas post-Isthmian C. magdalenae expansion was enabled by gene flow across the lower Magdalena valley and Central American lowlands. Time-calibrated phylogenetics indicate that the C. magdalenae colonized lower Central America in the Pliocene (3.7 MYA; Ma), the divergence Atrato-Magdalena occurred in Late Pliocene (3.0 Ma) and the split Ranchería-Magdalena during the Middle Pleistocene (1.3 Ma). Updated geographic distribution data support the hypothesis that the Cordillera de Talamanca functions as a barrier to northward expansion of C. magdalenae in Central America.

5.
Int Ophthalmol ; 44(1): 215, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38705919

RESUMEN

PURPOSE: There is limited literature on the ocular manifestations in patients with psoriasis. Therefore, this study aimed to identify the prevalence of and factors associated with ocular manifestations in adults with psoriasis. METHODS: This cross-sectional study included Brazilian adults with psoriasis. The dermatological evaluation included diagnosis, clinical form, Psoriasis Area and Severity Index (PASI) measurement, and location of the lesions. Patients underwent a full ophthalmological examination, including the Schirmer I test, Rose Bengala staining, and tear breakup time tests. The results were analyzed using chi-square and Pearson's linear correlation tests. RESULTS: Of the 130 patients assessed, 118 (90.8%) exhibited ocular abnormalities, with meibomian gland dysfunction (MGD) being the most prevalent (59.2%), followed by dry eye disease (DED) (56.2%). A significant correlation was observed between MGD and PASI (p = 0.05), and between MGD and certain treatment modalities. DED was significantly associated with PASI (p < 0.05). Concurrent use of acitretin was identified as an independent predictor of MGD (odds ratio [OR] = 3.5, p < 0.05), whereas PASI was a protective factor against DED (OR = 0.39, p < 0.01). CONCLUSION: Given the high prevalence of eye disease among individuals with psoriasis, routine ophthalmological assessments are recommended to prevent possible ocular complications.


Asunto(s)
Síndromes de Ojo Seco , Psoriasis , Humanos , Estudios Transversales , Masculino , Psoriasis/epidemiología , Psoriasis/complicaciones , Femenino , Brasil/epidemiología , Adulto , Persona de Mediana Edad , Prevalencia , Síndromes de Ojo Seco/epidemiología , Síndromes de Ojo Seco/etiología , Síndromes de Ojo Seco/diagnóstico , Disfunción de la Glándula de Meibomio/epidemiología , Disfunción de la Glándula de Meibomio/diagnóstico , Disfunción de la Glándula de Meibomio/etiología , Índice de Severidad de la Enfermedad , Anciano , Adulto Joven
6.
Vision (Basel) ; 8(2)2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38804351

RESUMEN

This study aimed to determine the pars plana length in postmortem human eyes using advanced morphometric techniques and correlate demographics to ocular metrics such as age, sex, ethnicity, and axial length. Between February and July 2005, we conducted a cross-sectional observational study on 46 human cadaver eyes deemed unsuitable for transplant by the SBO Eye Bank. The morphometric analysis was performed on projected images using a surgical microscope and a video-microscopy system with a 20.5:1 correction factor. The pars plana length was measured three times per quadrant, with the final value being the mean of these measurements. Of the 46 eyes collected, 9 were unsuitable for the study due to technical constraints in conducting intraocular measurements. Overall, the average axial length was 25.20 mm. The average pars plana length was 3.8 mm in all quadrants, with no measurements below 2.8 mm or above 4.9 mm. There were no statistically significant variations across quadrants or with age, sex, axial length, or laterality. Accurately defining the pars plana dimensions is crucial for safely accessing the posterior segment of the eye and minimizing complications during intraocular procedures, such as intravitreal injections and vitreoretinal surgeries.

7.
PLoS One ; 19(5): e0296593, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38805480

RESUMEN

BACKGROUND: Ensuring optimal nutrition through early breastfeeding is vital for infant mental development and overall health. HIV infections complicate decisions regarding exclusive breastfeeding, jeopardizing effective infant and young child feeding, which affects nutrition and health outcomes. Recognizing the lack of evidence on barriers to infant feeding in the context of HIV in Tanzania, this study was conducted to explore individual, household, and community obstacles in the Ilala district, Dar es Salaam. MATERIALS AND METHODS: A case study design employing a qualitative approach was used. The study was executed at the Reproductive and Child Health (RCH) Clinic within Amana Regional Referral Hospital, Mnazi Mmoja Health Centre, and Buguruni Health Centre. Data collection ensued through the purposive sampling of healthcare providers and HIV-positive mothers, utilizing in-depth interview techniques. The textual data accrued were analyzed using inductive and deductive content analysis strategies, thereby enabling the delineation and formulation of principal thematic constructs. RESULTS: The study involved interviews with twenty-seven key informants, encompassing HIV-positive mothers, nurses, clinicians, and community-based healthcare workers. The analysis of these interviews resulted in the identification of three major themes. Firstly, individual barriers to exclusive breastfeeding were delineated, encompassing sub-themes such as occupation-related hectic schedules, early motherhood-related non-compliance to safe infant feeding directives, postpartum depression, and issues related to breast sores and abscesses. Secondly, household-level barriers were identified, highlighting challenges like food insecurity and inaccessibility to key resources, the influence of male partners and family members on decision-making, and barriers arising from non-disclosure of HIV status affecting Exclusive Breastfeeding (EBF) support. Lastly, community-level barriers were explored, revealing a sub-theme related to the low retentivity of HIV-positive women in the Prevention of Mother-to-Child Transmission (PMTCT) programs. CONCLUSIONS: Individual barriers encompass practical, psychological, and physical challenges, while household-level obstacles include food insecurity, limited resources, and family dynamics influencing decisions. At the community level, there's a concern about the low retentivity of HIV-positive women in PMTCT programs, indicating broader societal challenges in supporting exclusive breastfeeding. There is a need for tailored interventions at individual, household, and community levels to promote and support optimal infant feeding practices among HIV-positive women.


Asunto(s)
Lactancia Materna , Infecciones por VIH , Madres , Investigación Cualitativa , Humanos , Lactancia Materna/psicología , Tanzanía/epidemiología , Femenino , Adulto , Madres/psicología , Infecciones por VIH/psicología , Infecciones por VIH/epidemiología , Lactante , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Masculino , Recién Nacido , Adulto Joven
8.
Polymers (Basel) ; 16(8)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38675000

RESUMEN

Hydrogels are three-dimensional crosslinked materials known for their ability to absorb water, exhibit high flexibility, their biodegradability and biocompatibility, and their ability to mimic properties of different tissues in the body. However, their application is limited by inherent deficiencies in their mechanical properties. To address this issue, reduced graphene oxide (rGO) and tannins (TA) were incorporated into alginate hydrogels (Alg) to evaluate the impact of the concentration of these nanomaterials on mechanical and adhesive, as well as cytotoxicity and wound-healing properties. Tensile mechanical tests demonstrated improvements in tensile strength, elastic modulus, and toughness upon the incorporation of rGO and TA. Additionally, the inclusion of these materials allowed for a greater energy dissipation during continuous charge-discharge cycles. However, the samples did not exhibit self-recovery under environmental conditions. Adhesion was evaluated on pig skin, revealing that higher concentrations of rGO led to enhanced adhesion, while the concentration of TA did not significantly affect this property. Moreover, adhesion remained consistent after 10 adhesion cycles, and the contact time before the separation between the material and the surface did not affect this property. The materials were not cytotoxic and promoted healing in human fibroblast-model cells. Thus, an Alg/rGO/TA hydrogel with enhanced mechanical, adhesive, and wound-healing properties was successfully developed.

9.
Nutrients ; 16(8)2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38674918

RESUMEN

As gluten may trigger gastrointestinal disorders (GIDs), its presence or absence in the diet can change the diversity and proportion of gut microbiota. The effects of gluten after six weeks of a double-blind, placebo-controlled intervention with a gluten-free diet (GFD) were studied in participants with GIDs suffering from migraines and atopic dermatitis (n = 46). Clinical biomarkers, digestive symptoms, stool, the Migraine Disability Assessment questionnaire, and zonulin levels were analyzed. Next-generation sequencing was used to amplify the 16S rRNA gene of bacteria and the internal transcribed spacer (ITS) regions of fungi. The GFD increased Chao1 fungal diversity after the intervention, while the fungal composition showed no changes. Bacterial diversity and composition remained stable, but a positive association between bacterial and fungal Chao1 diversity and a negative association between Dothideomycetes and Akkermansia were observed. GIDs decreased in both groups and migraines improved in the placebo group. Our findings may aid the development of GID treatment strategies.


Asunto(s)
Dieta Sin Gluten , Enfermedades Gastrointestinales , Microbioma Gastrointestinal , Glútenes , Trastornos Migrañosos , Humanos , Trastornos Migrañosos/microbiología , Femenino , Masculino , Enfermedades Gastrointestinales/microbiología , Adulto , Método Doble Ciego , Glútenes/efectos adversos , Persona de Mediana Edad , Dermatitis Atópica/microbiología , Heces/microbiología , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Hongos , ARN Ribosómico 16S , Precursores de Proteínas , Haptoglobinas
10.
J Control Release ; 368: 566-579, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38438093

RESUMEN

Intravenous (IV) iron-carbohydrate complexes are widely used nanoparticles (NPs) to treat iron deficiency anaemia, often associated with medical conditions such as chronic kidney disease, heart failure and various inflammatory conditions. Even though a plethora of physicochemical characterisation data and clinical studies are available for these products, evidence-based correlation between physicochemical properties of iron-carbohydrate complexes and clinical outcome has not fully been elucidated yet. Studies on other metal oxide NPs suggest that early interactions between NPs and blood upon IV injection are key to understanding how differences in physicochemical characteristics of iron-carbohydrate complexes cause variance in clinical outcomes. We therefore investigated the core-ligand structure of two clinically relevant iron-carbohydrate complexes, iron sucrose (IS) and ferric carboxymaltose (FCM), and their interactions with two structurally different human plasma proteins, human serum albumin (HSA) and fibrinogen, using a combination of cryo-scanning transmission electron microscopy (cryo-STEM), x-ray diffraction (XRD), small-angle x-ray scattering (SAXS) and small-angle neutron scattering (SANS). Using this orthogonal approach, we defined the nano-structure, individual building blocks and surface morphology for IS and FCM. Importantly, we revealed significant differences in the surface morphology of the iron-carbohydrate complexes. FCM shows a localised carbohydrate shell around its core, in contrast to IS, which is characterised by a diffuse and dynamic layer of carbohydrate ligand surrounding its core. We hypothesised that such differences in carbohydrate morphology determine the interaction between iron-carbohydrate complexes and proteins and therefore investigated the NPs in the presence of HSA and fibrinogen. Intriguingly, IS showed significant interaction with HSA and fibrinogen, forming NP-protein clusters, while FCM only showed significant interaction with fibrinogen. We postulate that these differences could influence bio-response of the two formulations and their clinical outcome. In conclusion, our study provides orthogonal characterisation of two clinically relevant iron-carbohydrate complexes and first hints at their interaction behaviour with proteins in the human bloodstream, setting a prerequisite towards complete understanding of the correlation between physicochemical properties and clinical outcome.


Asunto(s)
Anemia Ferropénica , Maltosa/análogos & derivados , Nanopartículas del Metal , Humanos , Hierro/química , Dispersión del Ángulo Pequeño , Ligandos , Difracción de Rayos X , Compuestos Férricos , Sacarato de Óxido Férrico/uso terapéutico , Anemia Ferropénica/tratamiento farmacológico , Nanopartículas del Metal/química , Fibrinógeno
11.
Polymers (Basel) ; 16(5)2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38475316

RESUMEN

The mechanical, thermal and gamma radiation attenuation properties of ethylene-propylene-diene monomer (EPDM)-based composites containing graphene nanoplatelets (GNs) and bismuth (III) oxide nanoparticles (B) were investigated. The use of polyethylene glycol (PEG) as a compatibilizer to improve the dispersion of the fillers was also investigated. The results showed that the combined use of these fillers resulted in a drastic increase in mechanical properties, reaching 123% and 83% of tensile strength and elongation at break, respectively, compared to those of EPDM. In contrast, the addition of PEG to composites containing EPDM GNs and B resulted in composites with lower values of mechanical properties compared to the EPDM/B/GN-based composite. However, the presence of PEG leads to obtaining a composite (EPDM/B/GNP) with a mass attenuation coefficient to gamma radiation (137Cs, 662 keV) superior to that composite without PEG. In addition, the composite EPDM, B and PEG exhibited an elongation at break 153% superior to unfilled EPDM. Moreover, the binary filler system consisting of 100 phr of bismuth (III) oxide and 10 phr of GN leads to reaching 61% of the linear damping coefficient of the EPDM composite compared to that value of the unfilled EPDM. The study of the morphology and the state of filler dispersion in the polymer matrix, obtained using scanning electron microscopy and energy-dispersive X-ray spectroscopy, respectively, provides a useful background for understanding the factors affecting the gamma radiation attenuation properties. Finally, the results also indicated that by adjusting the formulation, it is possible to tune the mechanical and thermal properties of EPDM composites reinforced with bismuth oxide and graphene nanoplatelets.

12.
Ann Glob Health ; 90(1): 18, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38463453

RESUMEN

Background: Non-communicable diseases (NCDs) arise from diverse risk factors with differences in the contexts and variabilities in regions and countries. Addressing such a complex challenge requires local evidence. Tanzania has been convening stakeholders every year to disseminate and discuss scientific evidence, policies, and implementation gaps, to inform policy makers in NCDs responses. This paper documents these dissemination efforts and how they have influenced NCDs response and landscape in Tanzania and the region. Methods: Desk review was conducted through available MOH and conference organizers' documents. It had both quantitative and qualitative data. The review included reports of the four NCDs conferences, conference organization, and conduct processes. In addition, themes of the conferences, submitted abstracts, and presentations were reviewed. Narrative synthesis was conducted to address the objectives. Recommendations emanated from the conference and policy uptake were reviewed and discussed to determine the impact of the dissemination. Findings: Since 2019, four theme-specific conferences were organized. This report includes evidence from four conferences. The conferences convened researchers and scientists from research and training institutions, implementers, government agencies, and legislators in Tanzania and other countries within and outside Africa. Four hundred and thirty-five abstracts were presented covering 14 sub-themes on health system improvements, financing, governance, prevention intervention, and the role of innovation and technology. The conferences have had a positive effect on governments' response to NCDs, including health care financing, NCDs research agenda, and universal health coverage. Conclusion: The National NCDs conferences have provided suitable platforms where stakeholders can share, discuss, and recommend vital strategies for addressing the burden of NCDs through informing policies and practices. Ensuring the engagement of the right stakeholders, as well as the uptake and utilization of the recommendations from these platforms, remains crucial for addressing the observed epidemiological transition in Tanzania and other countries with similar contexts.


Asunto(s)
Enfermedades no Transmisibles , Humanos , Tanzanía , Enfermedades no Transmisibles/prevención & control , Política de Salud , Formulación de Políticas , Factores de Riesgo
13.
Sci Rep ; 14(1): 4375, 2024 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-38388524

RESUMEN

The analysis of ceramide (Cer) and sphingomyelin (SM) lipid species using liquid chromatography-tandem mass spectrometry (LC-MS/MS) continues to present challenges as their precursor mass and fragmentation can correspond to multiple molecular arrangements. To address this constraint, we developed ReTimeML, a freeware that automates the expected retention times (RTs) for Cer and SM lipid profiles from complex chromatograms. ReTimeML works on the principle that LC-MS/MS experiments have pre-determined RTs from internal standards, calibrators or quality controls used throughout the analysis. Employed as reference RTs, ReTimeML subsequently extrapolates the RTs of unknowns using its machine-learned regression library of mass-to-charge (m/z) versus RT profiles, which does not require model retraining for adaptability on different LC-MS/MS pipelines. We validated ReTimeML RT estimations for various Cer and SM structures across different biologicals, tissues and LC-MS/MS setups, exhibiting a mean variance between 0.23 and 2.43% compared to user annotations. ReTimeML also aided the disambiguation of SM identities from isobar distributions in paired serum-cerebrospinal fluid from healthy volunteers, allowing us to identify a series of non-canonical SMs associated between the two biofluids comprised of a polyunsaturated structure that confers increased stability against catabolic clearance.


Asunto(s)
Esfingolípidos , Espectrometría de Masas en Tándem , Humanos , Esfingolípidos/análisis , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida con Espectrometría de Masas , Ceramidas/química , Esfingomielinas/química
14.
BMJ Open ; 14(2): e073859, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38373858

RESUMEN

OBJECTIVE: This study aimed to document lessons learnt and best practices for scaling up an innovative emergency transportation system, drawing insights from the m-mama programme implemented in Shinyanga, Tanzania. The m-mama pilot programme was implemented in phases from 2014 to 2016 in two districts and later scaled up to include all districts in Shinyanga region in 2017. The programme employed an emergency transportation system and technical and operational support of the health system to address the three delays leading to maternal and neonatal mortality. DESIGN: Cross-sectional, qualitative research with key healthcare system stakeholders from the national, regional and district levels. SETTING: The study was conducted in Kahama and Kishapu districts in Shinyanga, Tanzania. The two districts were selected purposefully to represent the programme implementation districts' rural and urban or semiurban settings. PARTICIPANTS: District, regional and national stakeholders involved in implementing the m-mama pilot programme in Shinyanga were interviewed between February and March 2022. RESULTS: Lessons learnt from implementing the m-mama programme were grouped into four key themes: community engagement, emergency transportation system, government engagement, and challenges and constraints in technical implementation. Stakeholder engagement and collaboration at all levels, community involvement in implementation, adherence to local contexts and effective government partnerships were identified as key drivers for programme success. Coordination, supervision and infrastructure enhancement were crucial in implementing the emergency transportation system. CONCLUSIONS: Facilitating community involvement, understanding the local context and adapting to existing structures can enhance programme ownership and utilisation. The government serves as the central coordinator, overseeing resource mobilisation and distribution. A well-executed and coordinated emergency transportation system holds promise in addressing delays and curbing maternal and neonatal mortality. Collaborative knowledge-sharing among implementers is essential for identifying best practices and gaining insights into practical strategies for addressing anticipated challenges.


Asunto(s)
Atención a la Salud , Mortalidad Infantil , Recién Nacido , Humanos , Tanzanía , Estudios Transversales , Investigación Cualitativa
15.
Behav Res Methods ; 56(1): 318-329, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36622558

RESUMEN

Fish are the most species-rich vertebrate group, displaying vast ecological, anatomical and behavioural diversity, and therefore are of major interest for the study of behaviour and its evolution. However, with respect to other vertebrates, fish are relatively underrepresented in psychological and cognitive research. A greater availability of easily accessible, flexible, open-source experimental platforms that facilitate the automation of task control and data acquisition may help to reduce this bias and improve the scalability and refinement of behavioural experiments in a range of different fish species. Here we present GoFish, a fully automated platform for behavioural experiments in aquatic species. GoFish includes real-time video tracking of subjects, presentation of stimuli in a computer screen, an automatic feeder device, and closed-loop control of task contingencies and data acquisition. The design and software components of the platform are freely available, while the hardware is open-source and relatively inexpensive. The control software, Bonsai, is designed to facilitate rapid development of task workflows and is supported by a growing community of users. As an illustration and test of its use, we present the results of two experiments on discrimination learning, reversal, and choice in goldfish (Carassius auratus). GoFish facilitates the automation of high-throughput protocols and the acquisition of rich behavioural data. Our platform has the potential to become a widely used tool that facilitates complex behavioural experiments in aquatic species.


Asunto(s)
Conducta Animal , Programas Informáticos , Humanos , Animales , Aprendizaje Discriminativo
16.
Rev Sci Instrum ; 94(4)2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38081256

RESUMEN

The characterization of the mechanical behavior of shape memory thin film alloys is essential for their application as microactuators. Depending on the particular application, different elements have been considered for the fabrication of ternary NiTi-based alloys in order to shift the martensitic transformation toward a lower or a higher temperature range. This work presents the design and implementation of a specific device to perform thermal cycles at constant stress on film-like samples over a wide temperature range, between -130 and 300 °C. The uniaxial stress application, the elongations and contractions measurements associated with the martensitic transformations, and the cooling and heating methods are detailed in the present work. The fabrication and operation features of this relatively low cost device facilitate and promote the study of shape memory thin films.

17.
An Acad Bras Cienc ; 95(4): e20190182, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38088692

RESUMEN

The present study aimed was to evaluate the spatial variability of weed species by means of phytosociological parameters and their correlations with the physical-chemical soil properties, under semiarid climate conditions. Weed phytosociology and soil characterization were carried out in two areas one newly deforested area covering 8.86 ha, and one experimental agricultural area covering 24.7 ha; both in the semi-arid region of Brazil. Weed and soil were sampled by following georeferenced grids in each area. Biomass and the total number of weed individuals, as well as soil properties, were mapped by the ordinary Kriging method. The predominant herbaceous plants in the newly deforested area were Hexasepalum teres and Digitaria insularis. The weed species that predominated in the agricultural area were Cyperus rotundus L., Euphorbia heterophylla L. and Herissantia Crispa (L.) Brizicky; the latter species outstanding for dry biomass (873.5g). Spatial dependence was observed for the predominant species, except for Digitaria insularis. The spatial distribution of these weeds was conditioned by soil K+ contents in both areas, and by sand content for the experimental agricultural area. Therefore, these two soil attributes resulted key factors for weed infestation in this semi-arid region.


Asunto(s)
Agricultura , Suelo , Humanos , Suelo/química , Brasil , Agricultura/métodos , Malezas , Biomasa
18.
Cell Death Dis ; 14(12): 797, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38057340
19.
Ann Glob Health ; 89(1): 89, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38107601

RESUMEN

Background: Five million people die every year from non-communicable diseases (NCDs) globally. In Tanzania, more than two-thirds of deaths are NCD-related. The country is investing in preventive and advocacy activities as well as interventions to reduce the burden. Of particular interest, the Ministry of Health (MoH) commemorates NCDs' week using a multisectoral and multi-stakeholders' approach. This paper highlights activities conducted during NCDs week with the aim of sharing lessons for other countries with similar context and burdens. Methods: A thorough review of official reports and the national strategic plans for NCDs was done including the 2020 and 2021 National NCDs' week reports, the National Strategic Plan for NCDs 2015-2020, and the National NCDs agenda. Findings: NCDs week is commemorated annually throughout the country involving the five key activities. First, community awareness and participation are encouraged through media engagement and community-based preventive and advocacy activities. Second, physical activities and sports festivals are implemented with a focus on developing and renovating infrastructures for sports and recreation. Third, health education is provided in schools to promote healthy behaviors for secondary school adolescents in transition to adulthood. Fourth, health service provision and exhibitions are conducted involving screening for hypertension, diabetes, obesity, alcohol use, and physical activities. The targeted screening of NCDs identified 10% of individuals with at least one NCD in 2020. In 2021, a third of all screened individuals were newly diagnosed with hypertension, and 3% were found to have raised blood glucose levels. Fifth, the national NCDs scientific conferences conducted within the NCDs week provide an avenue for stakeholders to discuss scientific evidence related to NCDs and recommend strategies to mitigate NCDs burden. Conclusion: The initiation of NCDs week has been a cornerstone in advocating for NCDs control and prevention in the country. It has created awareness on NCDs, encourage healthy lifestyles and regular screening for NCDs. The multi-stakeholder and multi-sectoral approaches have made the implementation of the mentioned activities feasible and impactful. This has set an example for the united efforts toward NCD control and prevention at national, regional, and global platforms while considering contextual factors during adoption and implementation.


Asunto(s)
Diabetes Mellitus , Hipertensión , Enfermedades no Transmisibles , Adolescente , Humanos , Tanzanía/epidemiología , Enfermedades no Transmisibles/epidemiología , Enfermedades no Transmisibles/prevención & control , Educación en Salud , Diabetes Mellitus/epidemiología , Diabetes Mellitus/prevención & control , Hipertensión/epidemiología , Hipertensión/prevención & control
20.
Arch Biochem Biophys ; 750: 109805, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37913855

RESUMEN

BACKGROUND: The extracellular matrix (ECM) is a complex tridimensional scaffold that actively participates in physiological and pathological events. The objective of this study was to test whether structural proteins of the ECM and glycosaminoglycans (GAGs) may favor the retention of human apolipoprotein A-I (apoA-I) variants associated with amyloidosis and atherosclerosis. METHODS: Biopolymeric matrices containing collagen type I (Col, a main macromolecular component of the ECM) with or without heparin (Hep, a model of GAGs) were constructed and characterized, and used to compare the binding of apoA-I having the native sequence (Wt) or Arg173Pro, a natural variant inducing cardiac amyloidosis. Protein binding was observed by fluorescence microscopy and unbound proteins quantified by a colorimetric assay. RESULTS: Both, Wt and Arg173Pro bound to the scaffolds containing Col, but the presence of Hep diminished the binding efficiency. Col-Hep matrices retained Arg173Pro more than the Wt. The retained protein was only partially removed from the matrices with saline solutions, indicating that electrostatic interactions may occur but are not the main driving force. Using in addition thermodynamic molecular simulations and size exclusion chromatography approaches, we suggest that the binding of apoA-I variants to the biopolymeric matrices is driven by many low affinity interactions. CONCLUSIONS: Under this scenario Col-Hep scaffolds contribute to the binding of Arg173Pro, as a cooperative platform which could modify the native protein conformation affecting protein folding. GENERAL SIGNIFICANCE: We show that the composition of the ECM is key to the protein retention, and well characterized biosynthetic matrices offer an invaluable in vitro model to mimic the hallmark of pathologies with interstitial infiltration such as cardiac amyloidosis.


Asunto(s)
Amiloidosis , Heparina , Humanos , Amiloidosis/metabolismo , Apolipoproteína A-I/genética , Apolipoproteína A-I/química , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Heparina/metabolismo
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