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The 2014 chikungunya outbreak in the Dominican Republic resulted in intense local transmission, with high postoutbreak seroprevalence. The resulting population immunity will likely minimize risk for another large outbreak through 2035, but changes in population behavior or environmental conditions or emergence of different virus strains could lead to increased transmission.

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have emerged as a potent therapeutic option for the management of obesity, demonstrating exceptional efficacy in several large-scale clinical trials. Despite their promising therapeutic outcomes, the rising popularity of these agents raises significant concerns, particularly regarding their off-label use by individuals seeking weight loss for aesthetic reasons rather than addressing underlying metabolic health conditions. This article critically evaluates the efficacy and safety of GLP-1 RAs in obesity management. Additionally, it explores the economic implications and ethical challenges associated with the increasing demand for GLP-1 RAs. By addressing these dimensions, this article aims to facilitate informed and responsible decision-making in clinical practice, highlighting the need for individualized patient assessments and careful consideration of both short- and long-term safety risks.

Little is known about the epidemiology of leptospirosis in the Dominican Republic, the second most populous country in the Caribbean. We report on findings from a multi-stage household survey across two regions in the country that reveals a previously under-estimated burden of human Leptospira infection. Our findings, based on the reference-standard microscopic agglutination test, indicate a complex picture of serogroup diversity, spatial heterogeneity in infection and risk, and a marked discrepancy between reported cases and serologically estimated infections. Given an overall seroprevalence of 11.3% (95% CI: 10.8-13.0%) and a lower estimated force of infection (0.30% per year [0.27%-0.35%]) the number of infections may exceed national reported case data by 145-fold or more. Icterohaemorrhagiae, associated with severe Weil's disease, was the most commonly identified serogroup with a serogroup-specific prevalence of 4.4%. Consistent with other settings, risk factors including age, male sex, and rat exposure were associated with higher seroprevalence. Our study highlights the need for targeted public health interventions informed by serogroup-specific dynamics, detailed spatial analyses, knowledge of local animal reservoirs, and strengthened laboratory surveillance to effectively control this pathogen.

ABSTRACTThe present work advances a methodology to optimise variables involved in fluid dynamic phenomena for augmented wind turbines. Particularly, the study focuses on improving the performance of a convergent-divergent augmented wind turbine based on eolic cells designed to increase wind speed at the throat section, where a peripherally supported magnetic levitation rotor will be installed as part of a novel wind energy system for distributed generation. Previous studies focused on maximising average wind velocity as the target variable. In contrast, this study shifted its focus to power density, resulting in more effective and consistent results. Numerical axisymmetric computational fluid dynamics simulations were conducted to determine the impact of these improvements. Response surfaces were created for parametric analysis, and the metamodel of optimal prognosis was implemented to provide accuracy. The results indicate a significant improvement in available power, with an average increase of up to 12.5 times compared to non-augmented conditions.

Abstract Objective The objective of the study was to understand the role of self-reported drinking behavior on liver health after achieving sustained viral response (SVR) among HCV patients. Results The study was conducted in HCV treatment provider clinics in three cities in Georgia: Tbilisi, Batumi, and Telavi. Face-to-face interviews were conducted using a questionnaire developed specifically for this study. 9.5% considered themselves heavy drinkers, while 94.2% were aware that heavy alcohol consumption can progress liver fibrosis. During treatment, 97.8% abstained from alcohol, while 76.6% reported resuming drinking after achieving SVR. Additionally, 52.1% believed that moderate alcohol intake is normal for individuals with low fibrosis scores. Liver fibrosis improvement was more prevalent among individuals who abstained from alcohol after HCV diagnosis (85.4% vs. 71.4%, p

Summary: Background: Individual immune responses to SARS-CoV-2 are well-studied, while the combined effect of these responses on population-level immune dynamics remains poorly understood. Given the key role of population immunity on pathogen transmission, delineation of the factors that drive population immune evolution has critical public health implications. Methods: We enrolled individuals 5 years and older selected using a multistage cluster survey approach in the Northwest and Southeast of the Dominican Republic. Paired blood samples were collected mid-pandemic (Aug 2021) and late pandemic (Nov 2022). We measured serum pan-immunoglobulin antibodies against the SARS-CoV-2 spike protein. Generalized Additive Models (GAMs) and random forest models were used to analyze the relationship between changes in antibody levels and various predictor variables. Principal component analysis and partial dependence plots further explored the relationships between predictors and antibody changes. Findings: We found a transformation in the distribution of antibody levels from an irregular to a normalized single peak Gaussian distribution that was driven by titre-dependent boosting. This led to the convergence of antibody levels around a common immune setpoint, irrespective of baseline titres and vaccination profile. Interpretation: Our results suggest that titre-dependent kinetics driven by widespread transmission direct the evolution of population immunity in a consistent manner. These findings have implications for targeted vaccination strategies and improved modeling of future transmission, providing a preliminary blueprint for understanding population immune dynamics that could guide public health and vaccine policy for SARS-CoV-2 and potentially other pathogens. Funding: The study was primarily funded by the Centers for Disease Control and Prevention grant U01GH002238 (EN). Salary support was provided by Wellcome Trust grant 206250/Z/17/Z (AK) and the Australian National Health and Medical Research Council Investigator grant APP1158469 (CLL).

Background: Language analytic ability is well researched in the context of foreign language acquisition but its role in the acquisition of grammar in the native language is under investigation. Objectives: Our study explored the influence of language analytic ability and print exposure on receptive grammar and reading comprehension in childhood. Additionally, we investigated whether exposure to specific constructions through the written modality held an advantage over exposure in the audio modality. Method: We assessed the language analytic ability, reading comprehension, reading fluency, print exposure, and receptive grammar of 12-year-olds. Subsequently, we exposed them to written or spoken target constructions, followed by an assessment of receptive grammar. Linear regression models were used to analyse the contributions of reading fluency, print exposure, and language analytic ability to reading comprehension and receptive grammar. We also examined the influence of the intervention on receptive grammar. Results: Language analytic ability and print exposure significantly predicted receptive grammar. Print exposure significantly predicted reading comprehension and improvement in receptive grammar. Conclusion: Language analytic ability is important for grammar and reading comprehension development. Print exposure enhances reading comprehension by supporting vocabulary development and providing exposure to intricate structures. Both language analytic ability and experience are key factors in construction acquisition. Contribution: This study adds to the growing body of evidence emphasising the role of language analytic skills in native language grammar acquisition and advocates for explicit grammar teaching. Furthermore, it underscores the importance of adequate print exposure in grammar acquisition and the development of reading comprehension skills.

Abstract Image-guided radiofrequency ablation (RFA) is used to treat focal tumors in the liver and other organs. Despite potential advantages over surgery, hepatic RFA can promote local and distant tumor growth by activating pro-tumorigenic growth factor and cytokines. Thus, strategies to identify and suppress pro-oncogenic effects of RFA are urgently required to further improve the therapeutic effect. Here, the proliferative effect of plasma of Hepatocellular carcinoma or colorectal carcinoma patients 90 min post-RFA was tested on HCC cell lines, demonstrating significant cellular proliferation compared to baseline plasma. Multiplex ELISA screening demonstrated increased plasma pro-tumorigenic growth factors and cytokines including the FGF protein family which uniquely and selectively activated HepG2. Primary mouse and immortalized human hepatocytes were then subjected to moderate hyperthermia in-vitro, mimicking thermal stress induced during ablation in the peri-ablational normal tissue. Resultant culture medium induced proliferation of multiple cancer cell lines. Subsequent non-biased protein array revealed that these hepatocytes subjected to moderate hyperthermia also excrete a similar wide spectrum of growth factors. Recombinant FGF-2 activated multiple cell lines. FGFR inhibitor significantly reduced liver tumor load post-RFA in MDR2-KO inflammation-induced HCC mouse model. Thus, Liver RFA can induce tumorigenesis via the FGF signaling pathway, and its inhibition suppresses HCC development.

Objective This study investigates the role of trust in shaping COVID-19 vaccine acceptance in the Dominican Republic (DR) during the COVID-19 pandemic.Design Cross-sectional household survey.Setting Randomly selected households across 134 clusters in the DR, from 30 June 2021 to 12 October 2021.Participants 5999 participants ≥16 years of age were enrolled.Outcome measures COVID-19 vaccine hesitancy (CVH) data were collected from participants ≥16 years of age and analysed as both an ordinal and binary variable.Results Overall, CVH was low (5.2% (95% CI 4.6% to 5.8%)), but more common among younger individuals, women and individuals of Mestizo ethnicity. Higher trust in local government, national government, scientists and local doctors (considered official sources) was associated with lower odds of CVH (OR 0.89 (95% CI 0.72 to 0.88), 0.89 (95% CI 0.81 to 0.98), 0.87 (95% CI 0.80 to 0.94) and 0.70 (95% CI 0.62 to 0.80), respectively). Higher trust in religious leaders, social media and traditional media (considered unofficial sources) was associated with higher odds of CVH, with respective ORs of 1.32 (95% CI 1.18 to 1.47), 1.30 (95% CI 1.19 to 1.41) and 1.08 (95% CI 0.97 to 1.22).Conclusion We report findings on CVH from a national household survey in the DR and identify overall low rates of CVH but marked heterogeneity by age, gender and ethnicity. Trust in unofficial versus official sources of information is associated with increased CVH. These findings highlight and quantify the importance of trust as a key parameter when considering public health communication strategies.

Abstract Introduction South Africa has one of the highest rates of internal migration on the continent, largely comprised of men seeking labour in urban centres. South African men who move within the country (internal migrants) are at higher risk than non‐migrant men of acquiring HIV yet are less likely to test or use pre‐exposure prophylaxis (PrEP). However, little is known about the mechanisms that link internal migration and challenges engaging in HIV services. Methods We recruited 30 internal migrant men (born outside Gauteng Province) during August 2022 for in‐depth qualitative interviews at two sites in Johannesburg (Gauteng) where migrants may gather, a factories workplace and a homeless shelter. Interviewers used open‐ended questions, based in the Theory of Triadic Influence, to explore experiences and challenges with HIV testing and/or PrEP. A mixed deductive inductive content analytic approach was used to review data and explain why participants may or may not use these services. Results Migrant men come to Johannesburg to find work, but unreliable income, daily stress and time constraints limit their availability to seek health services. While awareness of HIV testing is high, the fear of a positive diagnosis often overshadows the benefits. In addition, many men lack knowledge about the opportunity for PrEP should they test negative, though they express interest in the medication after learning about it. Additionally, these men struggle with adjusting to urban life, lack of social support and fear of potential stigma. Finally, the necessity to prioritize work combined with long wait times at clinics further restricts their access to HIV services. Despite these challenges, Johannesburg also presents opportunities for HIV services for migrant men, such as greater anonymity and availability of HIV information and services in the city as compared to their rural homes of origin. Conclusions Bringing HIV services to migrant men at community sites may ease the burden of accessing these services. Including PrEP counselling and services alongside HIV testing may further encourage men to test, particularly if integrated into counselling for livelihood and coping strategies, as well as support for navigating health services in Johannesburg.

Adsorptive–photocatalytic composites based on activated carbon (AC) and α-ferrous oxalate dihydrate (α-FOD) were synthesized by an original two-step method and subsequently used for the removal of phenol from aqueous solutions. To obtain the composites, ferrotitaniferous black mineral sands (0.6FeTiO3·0.4Fe2O3) were first dissolved in an oxalic acid solution at ambient pressure, and further treated under hydrothermal conditions to precipitate α-FOD on the AC surface. The ratio of oxalic acid to the mineral sand precursor was tuned to obtain composites with 8.3 and 42.7 wt.% of α-FOD on the AC surface. These materials were characterized by X-ray powder diffraction, scanning electron microscopy, and the nitrogen adsorption–desorption method. The phenol removal efficiency of the composites was determined during 24 h of adsorption under dark conditions, followed by 24 h of adsorption–photocatalysis under visible light irradiation. AC/α-FOD composites with 8.3 and 42.7 wt.% of α-FOD adsorbed 60% and 51% of phenol in 24 h and reached a 90% and 96% removal efficiency after 12 h of irradiation, respectively. Given its higher photocatalytic response, the 42.7 wt.% α-FOD composite was also tested during successive cycles of adsorption and adsorption–photocatalysis. This composite exhibited a reasonable level of cyclability (~99% removal after four alternated dark/irradiated cycles of 24 h and ~68% removal after three simultaneous adsorption–photocatalysis cycles of 24 h). The promising performance of the as-prepared composites opens several opportunities for their application in the effective removal of organic micropollutants from water.

The emergence of new resistant bacterial strains is a worldwide challenge. A resistant bacterial population can emerge from a single cell that acquires resistance or persistence. Hence, new ways of tackling the mechanism of antibiotic response, such as single cell studies are required. It is necessary to see what happens at the single cell level, in order to understand what happens at the population level. To date, linking the heterogeneity of single-cell susceptibility to the population-scale response to antibiotics remains challenging due to the trade-offs between the resolution and the field of view. Here we present a platform that measures the ability of individual E. coli cells to form small colonies at different ciprofloxacin concentrations, by using anchored microfluidic drops and an image and data analysis pipelines. The microfluidic results are benchmarked against classical microbiology measurements of antibiotic susceptibility, showing an agreement between the pooled microfluidic chip and replated bulk measurements. Further, the experimental likelihood of a single cell to form a colony is used to provide a probabilistic antibiotic susceptibility curve. In addition to the probabilistic viewpoint, the microfluidic format enables the characterization of morphological features over time for a large number of individual cells. This pipeline can be used to compare the response of different bacterial strains to antibiotics with different action mechanisms.

Abstract Background Pheochromocytoma (PCC) is rare in cats and plasma (PL) and urinary (U) metanephrines (metanephrine [MN]; normetanephrine [NMN]) measurement is rarely described in cats. Objectives We evaluated the utility of PL and U MNs measurement in 10 healthy cats and a cat with a confirmed diagnosis of pheochromocytoma (PheoCat), using liquid chromatography with tandem mass spectrometry (LC‐MS‐MS). Methods Urine and EDTA PL samples collected from each of the 10 cats and the PheoCat were promptly stored at −80°C and remained frozen until analysis. To evaluate U MNs stability, an additional urine sample collected from the healthy cats was refrigerated for 24 hours before freezing. Urinary creatinine concentration (Creat) was assessed using the same spot urine samples to calculate U MNs‐to‐creatinine ratios. Results The PL‐MN and PL‐NMN median concentrations of the healthy cats were 2.73 and 7.02 nmol/L, respectively. The median U‐MN/Creat and U‐NMN/Creat ratios were 70 and 139 μg/g, respectively. The PheoCat had a PL‐MN of 3.68 nmol/L, PL‐NMN of 66.27 nmol/L, U‐MN/Creat of 179 μg/g, and U‐NMN/Creat of 1262 μg/g. The PheoCat had markedly increased concentrations of both PL and U MNs when compared to the healthy cats. No significant difference was found between U MNs measured in urine samples that underwent 24 hours of refrigeration in comparison to those that were frozen immediately. Conclusions We report preliminary reference intervals for PL and U MNs in cats using LC‐MS‐MS and the potential clinical applicability of these biomarkers for the diagnosis of PCC in cats.

To assess changes in SARS-CoV-2 spike binding antibody prevalence in the Dominican Republic and implications for immunologic protection against variants of concern, we prospectively enrolled 2,300 patients with undifferentiated febrile illnesses in a study during March 2021–August 2022. We tested serum samples for spike antibodies and tested nasopharyngeal samples for acute SARS-CoV-2 infection using a reverse transcription PCR nucleic acid amplification test. Geometric mean spike antibody titers increased from 6.6 (95% CI 5.1–8.7) binding antibody units (BAU)/mL during March–June 2021 to 1,332 (95% CI 1,055–1,682) BAU/mL during May–August 2022. Multivariable binomial odds ratios for acute infection were 0.55 (95% CI 0.40–0.74), 0.38 (95% CI 0.27–0.55), and 0.27 (95% CI 0.18–0.40) for the second, third, and fourth versus the first anti-spike quartile; findings were similar by viral strain. Combining serologic and virologic screening might enable monitoring of discrete population immunologic markers and their implications for emergent variant transmission.

Objective. Colistin is an antibiotic of last resort for treating serious Gram-negative bacterial infections. However, the misuse of colistin, especially as an animal growth promoter, has contributed to increasing antimicrobial resistance, mediated mainly through plasmid transfer of the mcr-1 gene. This study assessed the prevalence of phenotypic and molecular colistin resistance in Escherichia coli and Klebsiella pneumoniae in Ecuador in healthy humans and their chickens and pigs. Methods. Fecal samples were collected from humans and their chickens and pigs in two rural coastal and Amazon regions between April and August 2020. Gram-negative bacteria were isolated and identified using conventional techniques. Phenotypic resistance was determined using the broth microdilution technique, and the mcr-1 gene was detected using conventional polymerase chain reaction. Results. A total of 438 fecal samples were obtained from 137 humans, 147 pigs and 154 chickens. The prevalence of E. coli isolates was 86.3% (378/438) and K. pneumoniae, 37.4% (164/438). Overall, the mcr-1 gene was found in 90% (340/378) of E. coli isolates, with higher prevalences found in isolates from coastal regions (96.5%, 191/198), humans (95.6%, 111/116) and chickens (91.8%, 123/134); for K. pneumoniae, the gene was found in 19.5% (32/164) of isolates, with equal distribution between regions and hosts. Only four isolates, two E. coli and two K. pneumoniae, showed phenotypic resistance: mcr-1 was present in both E. coli strains but absent in the K. pneumoniae strains. Conclusions. Despite a low prevalence of phenotypic resistance to colistin, the high prevalence of the mcr-1 gene in E. coli is of concern. Ecuador’s ban on using colistin in animal husbandry must be enforced, and continual monitoring of the situation should be implemented.

Context Due to the interesting potential of essential oils (EO) against cholinesterases and their close relation in Alzheimer’s disease, the EO of Lepechinia betonicifolia (Lam) Epling (Lamiaceae), a native shrub from Ecuador, was assessed. Chemical profiling and enantiomeric distribution were also recorded for the first time. Objective To analyse the chemical profile including the enantiomeric composition and anticholinesterase effect exerted by EO of L. betonicifolia. Materials and methods The EO of L. betonicifolia fresh aerial parts was obtained by hydrodistillation in a Clevenger-type apparatus. Physical properties were determined according to standard norms. The chemical composition was determined by GC-MS and GC-FID. Enantioselective GC-MS analysis was carried out by using a capillary chiral column. Anticholinesterase effect was assessed by Ellman’s method with acetylthiocoline as substrate and Ellman’s reagent (DTNB) to detect its hydrolysis at 405 nm for 60 min. Donepezil was used as a reference drug. EO was dissolved in methanol to reach 10 mg/mL concentration and two more 10× dilutions were included. Results Thirty-nine constituents were identified corresponding to 97.55% of the total oil composition. The main components were β-pinene (30.45%), sabinene (27.98%), α-pinene (4.97%), β-phellandrene (4.79%), E-caryophyllene (4.44%) and limonene (3.84%). L. betonicifolia EO exerted a strong inhibitory effect over the AChE enzyme with an IC50 value of 74.97 ± 1.17 μg/mL. Discussion and conclusions Current chemical characterisation and anticholinesterase effect of EO of L. betonicifolia encourage us to propose this EO as a candidate for the preparation of functional foods or as adjuvant therapy for Alzheimer’s disease.

Synthesis of silver nanoparticles with antibacterial properties using a one-pot green approach that harnesses the natural reducing and capping properties of cinnamon (Cinnamomum verum) bark extract is presented in this work. Silver nitrate was the sole chemical reagent employed in this process, acting as the precursor salt. Gas Chromatography-Mass Spectroscopy (GC-MS), High-Performance Liquid Chromatography (HPLC) analysis, and some phytochemical tests demonstrated that cinnamaldehyde is the main component in the cinnamon bark extract. The resulting bio-reduced silver nanoparticles underwent comprehensive characterization by Ultraviolet–Vis (UV-Vis) and Fourier Transform InfraRed spectrophotometry (FTIR), Dynamic Light Scattering (DLS), Transmission Electron Microscopy, and Scanning Electron Microscopy suggesting that cinnamaldehyde was chemically oxidated to produce silver nanoparticles. These cinnamon-extract-based silver nanoparticles (AgNPs-cinnamon) displayed diverse morphologies ranging from spherical to prismatic shapes, with sizes spanning between 2.94 and 65.1 nm. Subsequently, the antibacterial efficacy of these nanoparticles was investigated against Klebsiella, E. Coli, Pseudomonas, Staphylococcus aureus, and Acinetobacter strains. The results suggest the promising potential of silver nanoparticles obtained (AgNPs-cinnamon) as antimicrobial agents, offering a new avenue in the fight against bacterial infections.

Palm kernel cake (PKC), a byproduct of palm oil extraction, serves an important role in Ecuador’s animal feed industry. The emergence of yellow-orange fungal growth in PKC on some cattle farms in Ecuador sparked concerns within the cattle industry regarding a potential mycotoxin-producing fungus on this substrate. Due to the limited availability of analytical chemistry techniques in Ecuador for mycotoxin detection, we chose to isolate and identify the fungus to determine its association with mycotoxin-producing genera. Through molecular identification via ITS region sequencing, we identified the yellow-orange fungus as the yeast Candida ethanolica. Furthermore, we isolated two other fungi—the yeast Pichia kudriavzevii, and the fungus Geotrichum candidum. Molecular identification confirmed that all three species are not classified as mycotoxin-producing fungi but in contrast, the literature indicates that all three have demonstrated antifungal activity against Aspergillus and Penicillium species, genera associated with mycotoxin production. This suggests their potential use in biocontrol to counter the colonization of harmful fungi. We discuss preventive measures against the fungal invasion of PKC and emphasize the importance of promptly identifying fungi on this substrate. Rapid recognition of mycotoxin-producing and pathogenic genera holds the promise of mitigating cattle intoxication and the dissemination of mycotoxins throughout the food chain.

Diabetes mellitus (DM) is a global health concern characterized by a deficiency in insulin production. Considering the systemic toxicity and limited efficacy associated with current antidiabetic medications, there is the utmost need for natural, plant-based alternatives. Herbal medicines have experienced exponential growth in popularity globally in recent years for their natural origins and minimal side effects. Ecuador has a rich cultural history in ethnobotany that plays a crucial role in its people’s lives. This study identifies 27 Ecuadorian medicinal plants that are traditionally used for diabetes treatment and are prepared through infusion, decoction, or juice, or are ingested in their raw forms. Among them, 22 plants have demonstrated hypoglycemic or anti-hyperglycemic properties that are rich with bioactive phytochemicals, which was confirmed in several in vitro and in vivo studies. However, Bryophyllum gastonis-bonnieri, Costus villosissimus, Juglans neotropica, Pithecellobium excelsum, and Myroxylon peruiferum, which were extensively used in traditional medicine preparation in Ecuador for many decades to treat diabetes, are lacking in pharmacological elucidation. The Ecuadorian medicinal plants used to treat diabetes have been found to have several bioactive compounds such as flavonoids, phenolics, fatty acids, aldehydes, and terpenoids that are mainly responsible for reducing blood sugar levels and oxidative stress, regulating intestinal function, improving insulin resistance, inhibiting α-amylase and α-glucosidase, lowering gluconeogenic enzymes, stimulating glucose uptake mechanisms, and playing an important role in glucose and lipid metabolism. However, there is a substantial lack of integrated approaches between the existing ethnomedicinal practices and pharmacological research. Therefore, this review aims to discuss and explore the traditional medicinal plants used in Ecuador for treating DM and their bioactive phytochemicals, which are mainly responsible for their antidiabetic properties. We believe that the use of Ecuadorian herbal medicine in a scientifically sound way can substantially benefit the local economy and industries seeking natural products.

Even though tissue-engineered medicines are under intense academic, clinical, and commercial investigation, only a handful of products have been commercialised, primarily due to the costs associated with their prolonged manufacturing. While macromolecular crowding has been shown to enhance and accelerate extracellular matrix deposition in eukaryotic cell culture, possibly offering a solution in this procrastinating tissue-engineered medicine development, there is still no widely accepted macromolecular crowding agent. With these in mind, we herein assessed the potential of gum Arabic, gum gellan, gum karaya, and gum xanthan as macromolecular crowding agents in WS1 skin fibroblast cultures (no macromolecular crowding and carrageenan were used as a control). Dynamic light scattering analysis revealed that all macromolecules had negative charge and were polydispersed. None of the macromolecules affected basic cellular function. At day 7 (the longest time point assessed), gel electrophoresis analysis revealed that all macromolecules significantly increased collagen type I deposition in comparison to the non-macromolecular crowding group. Also at day 7, immunofluorescence analysis revealed that carrageenan; the 50 µg/mL, 75 µg/mL, and 100 µg/mL gum gellan; and the 500 µg/mL and 1000 µg/mL gum xanthan significantly increased both collagen type I and collagen type III deposition and only carrageenan significantly increased collagen type V deposition, all in comparison to the non-macromolecular crowding group at the respective time point. This preliminary study demonstrates the potential of gums as macromolecular crowding agents, but more detailed biological studies are needed to fully exploit their potential in the development of tissue-engineered medicines.

Corema (C.) album is a shrub endemic to the Atlantic coast and has been described as yielding beneficial effects for human health. Nevertheless, studies concerning the bioactivity of C. album leaves are scarce. This study aims at investigating the anticancer potential and mode of action, of an hydroethanolic extract of C. album leaves (ECAL) on triple-negative breast cancer. This is a poor survival breast cancer subtype, owing to its high risk of distant reappearance, metastasis rates and the probability of relapse. The ECAL ability to prevent tumor progression through (i) the inhibition of cell proliferation (cell viability); (ii) the induction of apoptosis (morphological changes, TUNEL assay, caspase-3 cleaved) and (iii) the induction of DNA damage (PARP1 and γH2AX) with (iv) the involvement of NF-κB and of ERK1/2 pathways (AlphaScreen assay) was evaluated. ECAL activated the apoptotic pathway (through caspase-3) along with the inhibition of ERK and NF-κB pathways causing DNA damage and cell death. The large polyphenolic content of ECAL was presumed to be accountable for these effects. The extract of C. album leaves can target multiple pathways and, thus, can block more than one possible means of disease progression, evidencing the anticancer therapeutic potential from a plant source.

In situ mineralogical and chemical analyses of rock samples using a space-prototype laser ablation ionization mass spectrometer along with unsupervised machine learning are powerful tools for the study of surface samples on planetary bodies. This potential is demonstrated through the examination of a thin section of a terrestrial rock sample in the laboratory. Autonomous isolation of mineral phases within the acquired mass spectrometric data is achieved with two dimensionality reduction techniques: uniform manifold approximation and projection (UMAP) and density-preserving variation of UMAP (densMAP), and the density-based clustering algorithm Hierarchical Density-Based Spatial Clustering of Applications with Noise (HDBSCAN). Both densMAP and UMAP yield comparable outcomes, successfully isolating the major mineral phases fluorapatite, calcite, and forsterite in the studied rock sample. Notably, densMAP reveals additional insights into the composition of the sample through outlier detection, uncovering signals from the trace minerals pyrite, rutile, baddeleyite, and uranothorianite. Through a grid search, the stability of the methods over a broad model parameter space is confirmed, revealing a correlation between the level of data preprocessing and the resulting clustering quality. Consequently, these methods represent effective strategies for data reduction, highlighting their potential application on board spacecraft to obtain direct and quantitative information on the chemical composition and mineralogy of planetary surfaces and to optimize mission returns through the unsupervised selection of valuable data.

Background: Physical, financial, social and emotional demands placed on caregivers caring for their children with severe intellectual disabilities (CWSID) could lead to high levels of burden. Aim: This study aimed to evaluate the potential level of burden experienced by South African caregivers and aimed to identify possible contributing risk factors for increased levels of caregiver burden. Setting: Online and community parent support groups. Methods: This quantitative survey design study utilised data from 218 South African caregivers of CWSID. Both descriptive and inferential statistics were used for analysis. Family is the main support for 67% of participants. Results: Moderate to severe levels of caregiver burden were reported. No definite links between potentially contributing demographic risk factors and the overall level of caregiver burden were found. Caregivers of CWSID need to receive the required support from an early stage in the child’s diagnosis to decrease potential caregiver burden and improve quality of life (QoL). Conclusion: Implications on intervention and prevention practices could inform the creation and implementation of a protocol to avert increased caregiver burden. Future research could be conducted to determine the implications of intervention towards CWSID and their family to decrease caregiver burden. Contribution: The study provided insight into the burden experienced by caregivers of CWSID. This is in line with the journal as it further proves how vulnerable CWSID are and the support they should be receiving from professionals.

Background: Learners with reading and writing difficulties (RWD) are accommodated in Mauritian government schools without formal curriculum adjustment and teacher support. Little is known about their RWD. The aim was to describe the characteristics of Grade 4 learners with RWD. Aim: To describe the characteristics of Grade 4 learners with RWD. Setting: Government primary schools in Mauritius, in urban and rural areas. Methods: Grade 4 learners with RWD from 20 randomly selected schools were identified with the Screening Tool for Learning Disorders (STLD). A comparative design was used. Parents of 67 learners with RWD (research group [RG]) gave consent. Forty-nine learners without RWD were selected as a control group (CG) based on academic performance and consent. Hearing loss and visual impairment were excluded. The Clinical Evaluation of Language Function Observation Rating Scale (CELF-5 ORS), the Schonell Spelling Test and the Gray Oral Reading Test were used. Results: The CELF-5 ORS showed a wide range of difficulties of the RG with speaking, listening, oral reading and writing. There were significant differences between the RG and CG with reading and spelling. Despite being in Grade 4 (mean age 9.0 years), the mean spelling age for the RG was 5.5 years, corresponding to a Grade 1 level. Positive correlations were found between the STLD and listening, speaking and reading on the CELF-5 ORS for the RG. The more likely it was that participants had specific learning disorders on the STLD, the worse the spelling. Those with a history of speech and language delay performed more poorly with reading and spelling. Conclusion: Difficulties were confirmed by all the measures. Diagnostic assessments for specific learning disorders are required to exclude intellectual disability and other comorbidities. There is a dire need for intervention programs for learners with RWD in mainstream government schools in Mauritius. Programs should include speech-language therapists and aim at prevention, identification, diagnosis and intervention. Contribution: The study is important for speech–language therapists working in the education system and primary school teachers. There is a dire need to implement intervention programs for learners with RWD in mainstream government schools in Mauritius.

Background: Despite extensive research on the specific learning disorder (developmental dyslexia) – SLD (DD), many fallacies still cause confusion amongst professionals worldwide. These myths involve the characteristics, diagnoses and treatment of SLD (DD) and should be eradicated. Aim: The authors aimed to determine the knowledge, needs and perspectives of South African professionals working with children with SLD (DD). Setting: A mixed-methods research design was implemented. Methods: A survey study was carried out and a sample of 108 respondents was obtained. The respondents include speech–language therapists (SLTs), occupational therapists (OTs) and psychologists. Results: Speech–language therapists and psychologists displayed better knowledge about the facts of SLD (DD), compared to OTs. Their knowledge levels were, however, not significantly affected by existing misconceptions surrounding the condition. The fallacy that SLD (DD) is caused by a visual impairment is still believed. An investigation into the professionals’ perspectives regarding the identification of SLD (DD) suggested that South African psychologists were the most confident of their ability to identify characteristics. Nonetheless, all professionals reported not being convinced of their ability to provide a differential diagnosis of the disorder. Statements regarding management highlighted the uncertainties about the importance of addressing phonological awareness skills in treatment. Additional training needs were also identified as SLTs, OTs and psychologists generally feel unprepared to assess and treat SLD (DD). Conclusion: The differences identified amongst professional groups were related to the knowledge of the facts and characteristics of SLD (DD) and the ability to identify and manage the condition. Additional training needs should be addressed. Contribution: The authors would like to acknowledge and thank the NRF for partially funding the publication of this article.

Summary: Background: Population-level SARS-CoV-2 immunological protection is poorly understood but can guide vaccination and non-pharmaceutical intervention priorities. Our objective was to characterise cumulative infections and immunological protection in the Dominican Republic. Methods: Household members ≥5 years were enrolled in a three-stage national household cluster serosurvey in the Dominican Republic. We measured pan-immunoglobulin antibodies against the SARS-CoV-2 spike (anti-S) and nucleocapsid glycoproteins, and pseudovirus neutralising activity against the ancestral and B.1.617.2 (Delta) strains. Seroprevalence and cumulative prior infections were weighted and adjusted for assay performance and seroreversion. Binary classification machine learning methods and pseudovirus neutralising correlates of protection were used to estimate 50% and 80% protection against symptomatic infection. Findings: Between 30 Jun and 12 Oct 2021 we enrolled 6683 individuals from 3832 households. We estimate that 85.0% (CI 82.1–88.0) of the ≥5 years population had been immunologically exposed and 77.5% (CI 71.3–83) had been previously infected. Protective immunity sufficient to provide at least 50% protection against symptomatic SARS-CoV-2 infection was estimated in 78.1% (CI 74.3–82) and 66.3% (CI 62.8–70) of the population for the ancestral and Delta strains respectively. Younger (5–14 years, OR 0.47 [CI 0.36–0.61]) and older (≥75-years, 0.40 [CI 0.28–0.56]) age, working outdoors (0.53 [0.39–0.73]), smoking (0.66 [0.52–0.84]), urban setting (1.30 [1.14–1.49]), and three vs no vaccine doses (18.41 [10.69–35.04]) were associated with 50% protection against the ancestral strain. Interpretation: Cumulative infections substantially exceeded prior estimates and overall immunological exposure was high. After controlling for confounders, markedly lower immunological protection was observed to the ancestral and Delta strains across certain subgroups, findings that can guide public health interventions and may be generalisable to other settings and viral strains. Funding: This study was funded by the US CDC.

Currently, most of all wind energy installed capacity in the world is located in wind farms and the reason behind that is related to the fact that conventional horizontal-axis wind turbines are highly efficient only at large scales, thus posing a concentration problem to the progress of energy transition and wind distributed generation. To address that problem, the present paper explores the utilization of a novel modular augmented wind turbine, based on Eolic Cells, to increase wind speed in order to harvest more power from the same wind resource as means to decentralize wind-energy generation around a wider range of wind sites suitable for distributed generation. The Eolic Cell’s wind velocity augmentation effect was simulated numerically by using computational fluid dynamics and optimized through a metamodel of optimal prognosis, for which geometries were parameterized using Bezier Curves and turbulence parameters were calibrated against field experiments. Results confirm the ability of this new device to substantially increase wind velocity and potentially achieve high levels of efficiency at a distributed-generation scale. The present work is the first release of a broader and more comprehensive research project on Eolic Cells as an alternative wind energy system for distributed generation. The whole research project involves studies on power augmentation curves, multivariable prognosis surfaces, optimum spacing layout, peripherally-supported wind turbine, power curves, prototype testing, as well as exhaustive wind-tunnel and field experiments, which are expected to be included in future releases of the present research project.

Incidence of COVID-19 has been associated with sociodemographic factors. We investigated variations in SARS-CoV-2 seroprevalence at sub-national levels in the Dominican Republic and assessed potential factors influencing variation in regional-level seroprevalence. Data were collected in a three-stage cross-sectional national serosurvey from June to October 2021. Seroprevalence of antibodies against the SARS-CoV-2 spike protein (anti-S) was estimated and adjusted for selection probability, age, and sex. Multilevel logistic regression was used to estimate the effect of covariates on seropositivity for anti-S and correlates of 80% protection (PT80) against symptomatic infection for the ancestral and Delta strains. A total of 6683 participants from 134 clusters in all 10 regions were enrolled. Anti-S, PT80 for the ancestral and Delta strains odds ratio varied across regions, Enriquillo presented significant higher odds for all outcomes compared with Yuma. Compared to being unvaccinated, receiving ≥2 doses of COVID-19 vaccine was associated with a significantly higher odds of anti-S positivity (OR 85.94, [10.95–674.33]) and PT80 for the ancestral (OR 4.78, [2.15–10.62]) and Delta strains (OR 3.08, [1.57–9.65]) nationally and also for each region. Our results can help inform regional-level public health response, such as strategies to increase vaccination coverage in areas with low population immunity against currently circulating strains.

Abstract Background The incidence of invasive pneumococcal disease (IPD) varies depending on a number of factors, including vaccine uptake, in both children and adults, the geographic location, and local serotype prevalence. There are limited data about the burden of Streptococcus pneumoniae (Spn), serotype distribution, and clinical characteristics of adults hospitalized due to IPD in Colombia. The objectives of this study included assessment of Spn serotype distribution, clinical characteristics, mortality, ICU admission, and the need for mechanical ventilation. Methods This was an observational, retrospective, a citywide study conducted between 2012 and 2019 in Bogotá, Colombia. We analyzed reported positive cases of IPD from 55 hospitals in a governmental pneumococcal surveillance program. Pneumococcal strains were isolated in each hospital and typified in a centralized laboratory. This is a descriptive study stratified by age and subtypes of IPD obtained through the analysis of medical records. Results A total of 310 patients with IPD were included, of whom 45.5% were female. The leading cause of IPD was pneumonia (60%, 186/310), followed by meningitis. The most frequent serotypes isolated were 19A (13.87%, 43/310) and 3 (11.94%, 37/310). The overall hospital mortality rate was 30.3% (94/310). Moreover, 52.6% (163/310 patients) were admitted to the ICU, 45.5% (141/310) required invasive mechanical ventilation and 5.1% (16/310) non-invasive mechanical ventilation. Conclusion Pneumococcal pneumonia is the most prevalent cause of IPD, with serotypes 19A and 3 being the leading cause of IPD in Colombian adults. Mortality due to IPD in adults continues to be very high.

Background: Dyslexia and attention deficit hyperactivity disorder (ADHD) are marked comorbid neurodevelopmental disorders with an estimated bidirectional comorbidity of 25% – 40%. Previous international studies have identified strong hereditary and neurological overlap between these disorders, but the comorbidity of these developmental disorders in a South African practice has not yet been explored. Methods: This retrospective study aimed to investigate the co-existence of ADHD and the specific learning disorder (SLD) related to reading known as developmental dyslexia (DD). Additionally, the study sought to determine possible correlations between the overlapping diagnostic factors of the two developmental disorders. The study database consisted of 847 learners ranging from 8 to 18 years of age. Study data were obtained through a parent questionnaire regarding scholastic difficulties as well as prior ADHD diagnosis and/or treatment. A comprehensive psychometric assessment of DD was conducted on each participant in the first language of educational instruction, that is English or Afrikaans, to establish a direct dyslexia diagnosis as inclusion criterion. Results: Of the 847 participants analysed in this study, 38.6% presented with a co-existing diagnosis of both ADHD and DD. However, there was no evidence of statistically significant interdependency between overlapping diagnostic factors of these two disorders. Conclusions: The zero-correlations in the mentioned areas may indicate an overlap of shared symptoms rather than of distinctive diagnostic approaches.

Reading and writing difficulties (RWD) in learners pose significant challenges not just for children but also for parents. While there is limited support available for children with RWD and their parents in Mauritian schools, research may reveal areas of parental need that speech-language therapists may address. The aim was to determine parents’ perspectives regarding their Grade 4 children with RWD in mainstream government schools in Mauritius. Teachers identified children with RWD with the Screening Tool for Learning Disorder, and parents were requested to participate in the study. Sixty-seven parents completed a questionnaire investigating their perspectives on the symptoms and causes of their child’s RWD and the ways in which they assist their child. The screening tool differentiated between children at risk of specific learning disorder (SLD) and children who indicated clear symptoms of SLD. The results of the tool did not correspond closely with the participants’ satisfaction with their child’s academic performance. The majority of participants could, however, identify RWD in their children when descriptions were given. Parents mostly cited laziness as the main cause of their child’s RWD. The results showed that participants had limited information about the causes and symptoms of RWD and SLD. There is a lack of awareness about the role of speech-language therapists in the intervention of RWD. There are limited resources and support for children with RWD, despite an inclusive education policy in Mauritius. Speech-language therapists and teachers should collaborate to support children with RWD and their parents using inclusive education strategies.

A multiplex PCR system (m-PCR) has been developed to accurately differentiate the five most important pathogenic Prototheca species, including the three species associated with infection in dairy cattle (P. ciferrii, P. blaschkeae, and P. bovis) and the two species associated with human infections (P. wickerhamii and P. cutis). The method is low-cost since it employs a simple “heat-shock” method in a TE buffer for DNA extraction. Furthermore, it requires only primers, a Taq polymerase, an agarose gel, and a molecular weight marker for identification. The method was based on published Prototheca cytochrome B sequences and was evaluated using reference strains from each of the five Prototheca species. The validity of the method was confirmed by identifying 50 strains isolated from milk samples. The specificity was tested in silico and with experimental PCR trials, showing no cross-reactions with other Prototheca species, as well as with bacteria, fungi, cows, algae, animals, or humans. The method could detect mixed infections involving two or three Prototheca species, providing a rapid test that delivers results within three hours.

Background: South Africa has a dearth of research regarding the management of children with dyslexia (CWD), which could be exacerbated by the apparent lack of parental support. South Africa has a unique educational, linguistic and socio-economic context; thus, more specific investigations were warranted into the perspectives and needs of parents and caregivers of CWD in South Africa. Aim: To determine the parental perspectives of the management of their CWD in South African schools. Setting: An online research survey was sent to South African parents with a CWD. Methods: A descriptive, embedded design, including both qualitative and quantitative aspects, was implemented. The study was cross-sectional in nature. Stratified sampling was used in which the participants were divided into two separate strata. Results: Results indicated that most parents of CWD had good knowledge regarding dyslexia in South Africa. Most parents with CWD had difficulty with the social stigma surrounding the disorder. Furthermore, parents were aware of their role in their CWD’s education; however, a lack of resources was evident in South Africa leading to poor parental experiences. Conclusion: There is a lack of resources and access to appropriate services such as multisensory teaching methods and accommodations in South Africa. Parents of CWD therefore did not receive enough support in the management of their child’s dyslexia. Future research should be conducted regarding South African teachers’ knowledge and perspectives regarding dyslexia and the management thereof. It was recommended that professionals trained in the management of dyslexia educate and advocate for CWD and their families.

ObjectiveTo identify risk factors for SARS-CoV-2 infection and for severe/critical COVID-19, and to assess the humoral response after COVID-19 in these patients.MethodsNationwide study of adult patients with inflammatory RMDs prospectively followed in the Rheumatic Diseases Portuguese Register—Reuma.pt—during the first 6 months of the pandemic. We compared patients with COVID-19 with those who did not develop the disease and patients with mild/moderate disease with those exhibiting severe/critical COVID-19. IgG antibodies against SARS-CoV-2 were measured ≥3 months after infection and results were compared with matched controls.Results162 cases of COVID-19 were registered in a total of 6,363 appointments. Patients treated with TNF inhibitors (TNFi; OR = 0.160, 95% CI 0.099–0.260, P < 0.001) and tocilizumab (OR 0.147, 95% CI 0.053–0.408, P < 0.001) had reduced odds of infection. Further, TNFi tended to be protective of severe and critical disease. Older age, major comorbidities, and rituximab were associated with an increased risk of infection and worse prognosis. Most patients with inflammatory RMDs (86.2%) developed a robust antibody response. Seroconversion was associated with symptomatic disease (OR 13.46, 95% CI 2.21–81.85, P = 0.005) and tended to be blunted by TNFi (OR 0.17, 95% CI 0.03–1.05; P = 0.057).ConclusionsTNFi and tocilizumab reduced the risk of infection by SARS-CoV-2. Treatment with TNFi also tended to reduce rates of severe disease and seroconversion. Older age, general comorbidities and rituximab were associated with increased risk for infection and worse prognosis, in line with previous reports. Most patients with RMDs developed a proper antibody response after COVID-19, particularly if they had symptomatic disease.

Abstract To study the effect of the incorporation of silver nanoparticles into polyvinyl alcohol (PVA) films on their optical and conducting properties, silver nanostructures with different sizes covering from spherical to polyhedral shapes were synthesized and embedded into the polymer. The sizes of the obtained silver nanostructures were analyzed by Dynamic Light Scattering (DLS), which exhibited high stability, attributed to their surface potential. Multimodal distributions suggest changes in shape ranging from spheres (~40 nm) to prisms (~100 nm), which was confirmed by Scanning Electron Microscopy (STEM/SEM) analysis. By embedding these nanostructures in polyvinyl alcohol (PVA), AgNPs loaded PVA polymer films were prepared, exhibiting a hypsochromic shift in the surface plasmon resonance band of the nanostructures. For conductivity determination of AgNPs loaded PVA polymer films, Electrochemical Impedance Spectroscopy (EIS) was used. The results indicated that the conductivity of the samples is highly dependent on the size and shape of the AgNPs embedded into the polymer, resulting in higher conductivity for smaller silver nanostructures.