Search Results (87)

Laurinterol, a halogenated sesquiterpene produced by red algae of the genus Laurencia, is one of the most characteristic compounds within the laurane and cyclolaurane families. This review compiles and examines current knowledge on laurinterol, integrating evidence on its occurrence, biosynthesis, biological activities, and structural features. Within a functional and ecological framework, laurinterol is proposed as an archetypal Smart Secondary Metabolite (SSM), a concept that reflects the convergence of structural singularity, high abundance within its biosynthetic context, broad biological activity, multi-target interactions, and ecological or chemotaxonomic relevance. This perspective highlights its role in adaptive processes within producing organisms and associated trophic networks. Laurinterol exhibits a broad bioactivity profile, including antimicrobial, antimycobacterial, cytotoxic, antiparasitic, enzyme inhibitory, antifouling, and insecticidal or repellent effects. Structure–activity relationship (SAR) studies remain limited and are mainly developed in specific models, particularly against Naegleria fowleri. The current intellectual property landscape related to laurinterol, including patent applications, granted patents, and technological development trends, is also examined. Overall, this review positions laurinterol as a structurally distinctive and functionally relevant marine metabolite within chemical ecology and marine natural products research. Full article

Dehydrothyrsiferol (DT), a brominated oxasqualenoid from the red alga Laurencia viridis, represents a compelling example of this framework. This review establishes DT as a model Smart Secondary Metabolite based on the convergence of a unique molecular architecture of rigid stereogroups connected by flexible bonds; a high metabolic yield (0.42% w/w of crude extract); potent selective bioactivity against kinetoplastids and drug-resistant tumors; multi-target modulation of protein phosphatase 2A (PP2A) and cell-surface integrins; and distinctive chemotaxonomic relevance within Macaronesian communities. Its biosynthesis proceeds through stereocontrolled epoxide-opening cascades, generating an evolutionarily refined scaffold. Ecologically, DT operates as a multifunctional shield, providing antifouling protection and deterring herbivory. Pharmacologically, it acts as a selective signaling modulator, triggering integrin-mediated cell death (IMD) in resistant cancer cells and inducing mitochondrial collapse in protozoa. In vivo studies in murine models of cutaneous leishmaniasis have demonstrated an 87% reduction in lesion size, reinforcing its promise as a lead structure. Full article

Ciprofloxacin (CIP) is an antibiotic that is widely used in humans and animals. However, the compound has been detected in animal-derived products and the environment due to its extensive use, causing serious concern for public health and environmental safety. The issue raises the urgent need to develop innovative techniques to monitor CIP. Therefore, this study aims to develop a simple and sensitive CIP sensor called the boron-doped diamond nanoparticle-modified screen-printed electrode (BDD NPs/SPE) and the nickel oxide nanoparticle-modified BDD NPs/SPE (NiO NPs/BDD NPs/SPE). NiO NPs were synthesized via green synthesis using Spatholobus littoralis Hassk. root extract as the reducing agent. The formation and characteristics of NiO NPs were then confirmed through a UV-Vis spectrophotometer, XRD, PSA, FT-IR, and XPS. The successful modification of SPE was confirmed through SEM-EDX, followed by measurements using square-wave voltammetry. The results showed that the modified SPE could detect CIP over a concentration range of 0.1–100 µM and produced a low detection limit of 0.109 µM for BDD NPs/SPE and 0.054 µM for NiO NPs/BDD NPs/SPE. The proposed method was successfully applied to the determination of CIP in commercial tablets, milk, and human urine, with a satisfactory % recovery from 95 to 100%. The current study successfully developed a simple yet highly sensitive sensor that enabled robust, reliable, and efficient detection of CIP, showing its strong potential for practical applications. Full article

Passiflora germplasm represents an important genetic resource for improving fruit yield and quality in breeding programs targeting semi-arid environments. This study aimed to assess the phenotypic diversity, genetic parameters, and breeding potential of Passiflora accessions conserved in the Passion Fruit Active Germplasm Bank of Embrapa Semiárido. A total of 55 accessions, predominantly Passiflora cincinnata Mast., were evaluated using morphoagronomic descriptors related to plant, flower, and fruit traits. Quantitative data were analyzed using mixed linear models (REML/BLUP) to estimate genetic parameters, and multivariate analyses were applied to characterize phenotypic divergence. Substantial phenotypic variability was observed, particularly for fruit-related traits. Fruit weight ranged from 43.25 to 142.88 g, pulp weight ranged from 7.86 to 51.37 g, and pulp yield ranged from 17.06% to 40.27% among accessions. Broad-sense heritability estimates for key fruit traits were moderate to high, reaching 0.50 for fruit weight, 0.49 for pulp weight, and 0.36 for pulp yield, indicating favorable prospects for selection. Principal Component Analysis explained 66.0% of the total variation in the first two components, with fruit size, pulp-related traits, and seed number contributing most strongly to accession differentiation. Multivariate analyses consistently identified accessions 1 and 16 as superior for fruit weight and pulp yield, whereas accession 55 combined high fruit weight with elevated soluble solid content (up to 14.24 °Brix) but lower pulp yield. Overall, the observed variability highlights the relevance of Passiflora germplasm conserved under semi-arid conditions as a valuable resource for breeding programs focused on fruit yield, quality, and adaptation to water-limited environments. Full article

As a part of an SAR study aimed at testing the antitumor activity of some C₁₅ acetogenins related to mycalin A, we report here the synthesis of the C-1 debromo-derivative of laurenciallene, a substance recently isolated from the red alga Laurencia obtusa. This new substance has been obtained by the selective, reductive debromination of the terminal bromoallene moiety of laurenciallene with Zn/AcOH. Its structure has been fully characterized by spectral methods, including 2D-NMR spectra. Full article

The concept of “Smart Secondary Metabolites” is introduced here to describe a privileged class of natural products defined by structural originality, biosynthetic adaptability, and broad interaction potential with biological systems. Elatol, a halogenated sesquiterpene chiefly produced by Laurencia red seaweeds and occasionally accumulated by their consumers, exemplifies this concept with remarkable clarity. Its biosynthesis unfolds from farnesyl diphosphate via γ-bisabolane cations, bromochlorination, and stereoselective cyclization to chamigrene scaffolds, generating both (+)- and (–)-enantiomers, two metabolites with clearly distinct potential ecological roles and pharmacological profiles. This review synthesizes the current state of knowledge on elatol’s distribution, biosynthetic origins, ecological relevance, and therapeutic potential. Elatol serves as a multifunctional chemical mediator, fulfilling defensive, communicative, and regulatory roles whose intensity shifts in response to herbivory, biofouling, temperature, and salinity. In parallel, its potent activities against infectious, metabolic, and neoplastic diseases highlight its growing value as a drug lead, reflected in a rising number of patent claims. Altogether, elatol emerges as a model Smart Secondary Metabolite whose ecological sophistication and biochemical versatility position it as a promising scaffold for marine-derived drug discovery. Full article

Background: Marine macroalgae has been studied by our research group as alternative sources of bioactive compounds with promising antiparasitic activity, particularly against Schistosoma mansoni. Objectives: This study aimed to employ a metabolomics-based approach to identify anthelminthic active compounds from the macroalgae Laurencia aldingensis Saito and Womersley 1974 and Laurencia dendroidea J. Agardh 1852. Methods: The algae were extracted using a dichloromethane/methanol mixture, followed by liquid–liquid partitioning and sequential chromatographic fractionation using solvents of varying polarities. The resulting fractions were tested for biological activity against adult Schistosoma mansoni worms. Detailed chemical characterization of the extracts was conducted via HPLC-DAD-MS/MS, with subsequent data alignment and statistical analysis (Pearson correlation) to associate specific chemical compounds with the observed bioactivity. Results: Non-polar fractions (hexane and dichloromethane) exhibited significant anthelminthic activity, substantially reducing parasite viability and reproduction. Specific subfractions obtained from the dichloromethane fraction demonstrated notable activity. Metabolomic analysis revealed considerable chemical diversity, emphasizing the presence of bromophenols and halogenated sesquiterpenes, including potentially novel compounds with therapeutic potential against schistosomiasis. Conclusions: The metabolomics approach proved effective in identifying promising bioactive compounds from Laurencia spp. macroalgae with activity against S. mansoni. Full article

(1) Background: Violence against healthcare professionals is becoming a growing concern for healthcare systems and a public health issue, and in Portugal it remains undocumented at a national level, leaving a critical knowledge gap. This scenario compromises the development of effective public policies and evidence-based institutional strategies, which are essential for guiding policymakers in the implementation of preventive measures and appropriate safety protocols to assess the nature, frequency, and key factors contributing to violence against healthcare professionals (doctors and nurses) in clinical settings. (2) Methods: This is a quantitative, descriptive, and cross-sectional study. The sample size was 440 professionals (n = 440). Between January and May 2024, healthcare professionals (physicians and nurses) working in four local health units located in the south of Portugal were invited to participate in this study via institutional e-mail. Data was collected using a structured questionnaire on the healthcare professional’s sociodemographic and work-related characteristics and aspects related to violence towards healthcare professionals in the workplace. Unconditional logistic regression models were fitted to compute crude odds ratios (ORs) and 95% confidence intervals (95%CIs) for the association between sociodemographic and work-related characteristics and violence at work. (3) Results: Nearly 40% of the healthcare professionals sampled reported having been victims of violence in the workplace, and, among these, the majority reported experiencing psychological violence (94.2%), followed by physical violence (46.2%), another type of violence (39.1%), and sexual violence (4.1%). Incidents were mostly occasional (65.5%), occurring during the daytime (51.5%) and on weekdays (84.8%). Healthcare professionals aged between 34 and 55 years old were approximately twice as likely to experience violence compared to those who were 56 years old or older (OR = 2.28; 95%CI 1.33–3.90). Also, those who had been with the organization for more than 4 years (5–7 years: OR = 2.37; 95%CI 1.05–5.37. ≥8 years: OR = 1.87; 95%CI 1.00–3.50), as well as those who worked shifts (OR = 1.84; 95%CI 1.25–2.72), reported incidents of violence more frequently. (4) Conclusions: The low response rate (12.5%) and cross-sectional design limit the generalizability of the results, which should be interpreted considering these methodological limitations. Workplace violence in Portugal is a reality, and it requires solutions. Information related to violent incidents must be comprehensively gathered to understand the full extent of the problem and develop prevention strategies based on potentially changeable risk factors to minimize the negative effects of workplace violence. Full article

Objectives: This study characterised and evaluated the stability, solubility, and in vitro drug release of OA- and AA-loaded SLNs. Methods: The OA- and AA-SLNs were formulated using the emulsion solvent evaporation method and characterised based on particle size (PS), polydispersity index (PDI), zeta potential (ZP), and transmission electron microscopy (TEM). Solubility studies were conducted in PBS (pH 1.2 and 6.8) and dH₂O using HPLC, while in vitro drug release was assessed in simulated intestinal fluid (SIF) (pH 6.8). Results: The optimised OA-SLNs (1:1 drug-to-lipid ratio) showed PS, PDI, ZP, and EE% values of 312.9 ± 3.617 nm, 0.157 ± 0.014, −17.0 ± 0.513 mV, and 86.54 ± 1.818%, respectively. The optimised AA-SLNs (1:2 drug-to-lipid: ratio) had a PS of 115.5 ± 0.458 nm, PDI of 0.255 ± 0.007, ZP of −11.9 ± 0.321 mV, and EE% of 76.22 ± 0.436%. The SLNs remained stable for 60 days at 4 °C and room temperature (p < 0.05). The solubility study revealed that free OA and AA showed no measurable values in the three solvents. However, OA-SLNs showed the highest solubility in H₂O (16-fold) followed by PBS at pH 6.8 (10-fold) and pH 1.2 (10-fold). AA-SLNs significantly improved the solubility in PBS at pH 6.8 (88-fold), compared to dH₂O (6-fold) and PBS at pH 1.2 (26-fold). In vitro drug release studies showed that OA release from the SLNs was significantly increased within 300 min (p < 0.05) compared to the free drug. Similarly, AA release from the SLNs was significantly increased within 300 min (p < 0.05) compared to free AA. Conclusions: These results demonstrate that SLNs enhance OA and AA solubility and drug release, suggesting a promising strategy for improving oral bioavailability and therapeutic efficacy. Full article

One of the most important steps in preclinical drug discovery is to demonstrate the in vivo efficacy of potential leishmanicidal compounds and good characteristics at the level of parasite killing prior to initiating human clinical trials. This paper describes the use of dehydrothyrsiferol (DT), isolated from the red alga Laurencia viridis, in a pharmaceutical form supported on Sepigel, and the in vivo efficacy against a mouse model of cutaneous leishmaniasis. Studying the ultrastructural effect of DT was also carried out to verify the suspected damage at the cellular level and determine the severity of damages produced in the homeostasis of promastigotes. BALB/c mice infected with Leishmania amazonensis were divided into four groups: untreated mice, mice treated with miltefosine orally and mice treated topically with 1% and 0.5% DT-Sepigel; treatment was carried out for two weeks. Treatment with DT significantly reduced the parasite load in skin, liver and spleen compared with the untreated group. In addition, DT-Sepigel at the lowest concentration (0.5%) showed the best results, reducing lesion size by 87% at 3 weeks post-treatment. DT-Sepigel has demonstrated to be a potent topical treatment that, in combined drug trials, may aim at combating cutaneous leishmaniasis. Full article

The Eastern Cape Province of South Africa is largely rural, with agriculture as the main livelihood for many households. However, the province has a semi-arid climate and reliance on rain-fed agriculture, which makes the region highly vulnerable to climate-related risks, particularly droughts. Smallholder farmers, who play a crucial role in food production and local economies, face significant challenges due to limited access to resources like irrigation, modern technology, and financial support, exacerbating their vulnerability to climate variability. These droughts cause severe losses in agricultural productivity, threatening food security, increasing poverty, and driving rural migration. Despite the potential benefits of adaptation strategies, many farmers lack the tools and knowledge to effectively cope with the increasing frequency and severity of droughts. This study examines how smallholder farmers in South Africa’s Eastern Cape Province perceive, experience, and cope with drought risk and its food and nutrition security implications. Using structured questionnaires, the authors collected data from 160 smallholder farmers and employed statistical analysis techniques, including a multinomial logit model. The study found that smallholder farmers understand drought risk but continue to face high vulnerability to adverse effects such as water scarcity, crop failure, increased disease incidence, and rising temperatures. Socioeconomic and institutional factors significantly influenced the adaptation strategies chosen by smallholder farmers. This study suggests that a combination of localized and modern adaptation approaches, supported by various institutional, policy, and technological interventions, is essential to enhance the resilience of these farmers. Specifically, localized strategies such as using traditional water management systems and crop diversification were effective in addressing region-specific climate challenges. At the same time, modern approaches like climate-resilient crop varieties and early-warning systems provided broader, more scalable solutions. Institutional support measures, such as access to climate information and extension services, policy interventions promoting sustainable practices, and technological advancements in irrigation and seed technologies, were key factors in improving adaptive capacity and reducing vulnerability. There is an urgent need to provide comprehensive support and empower farmers to adapt effectively, protect their livelihoods, and contribute to broader food security and poverty reduction efforts. This study highlights the importance of understanding and addressing the perceptions and experiences of smallholder farmers facing drought risk to ensure sustainable food production, income generation, and poverty alleviation. Full article

Background: Violence against health professionals is a global and growing problem, with significant impacts on the quality of care and the mental health of workers. Objectives: To analyze the level of knowledge, reporting practices and consequences of violence against health professionals in the Alentejo region (southern Portugal). Methods: This was an observational, cross-sectional study involving 440 health professionals (doctors and nurses). Data were collected using an online platform and a structured questionnaire created specifically for this study. In the statistical analysis, the data were described as counts and proportions and the X2 test was used considering a significance level of 0.05. Results: This study reveals that violence against health professionals in the southern region of Portugal is a frequent problem (40%), with a higher incidence among nurses (80%). Despite awareness of the existence and functioning of reporting channels, reporting is low (52%). The main causes are related to the health system, professionals and users. The consequences include mental health problems and a reduction in the quality of care provided. Suggested measures to combat violence include improving security, training and punishing aggressors. Conclusions: This study reveals that violence against health professionals in the southern region of Portugal is a frequent, under-reported problem with serious consequences for professionals and the quality of care. Full article

Taxonomy—the classification of species—is an important branch of biology that allows us to systematically understand and study biodiversity. Conventional taxonomy relies heavily on morphological and anatomical structures for classification, but recent discoveries of potentially cryptic species and morphological plasticity in many species underscore the importance of having an alternative or complementary method for species classification. In this paper, we discuss the emerging method of classification using biochemical signals, i.e., chemotaxonomy. We also present a case study on the feasibility of biomarker-based chemotaxonomy on the marine red alga Laurencia snackeyi using halogenated snyderane-type sesquiterpenes, which were proposed in earlier studies. Full article

Background: Addressing informal caregivers’ needs is essential for ensuring quality healthcare and promoting citizen-centred care. This systematic review assessed current knowledge about programmes aimed at meeting the needs of informal caregivers of adults who are dependent on others for daily life activities. Methods: Following the PRISMA guidelines, the electronic databases EBSCOhost Research Platform, MEDLINE, CINAHL, Scopus, Web of Science and The Virtual Health Library were searched for randomized experimental studies published between 2012 and 2022 that implemented programmes addressing informal caregivers’ needs to improve their experiences, health, and well-being. Quality was assessed using the standardized critical evaluation tools from the Joanna Briggs Institute. Two independent investigators performed the eligibility assessment and data extraction. Quantitative data on the effectiveness of interventions were collected, and the content of each intervention was synthesized and aggregated into categories, through narrative synthesis. Results: The majority of the included studies (n = 16) were conducted in European countries and implemented a structured intervention programme compared to the provision of usual care. The studies were of fair to high methodological quality, with a higher risk of bias related to blinding. The results supported the achievement of favourable health outcomes among informal caregivers, namely improvements in mental health (n = 3) and quality of life (n = 3) and a decrease in psychological symptomatology (n = 5) and burden (n = 3). None of the interventions reported adverse outcomes; however, five studies did not describe significant differences in the outcomes assessed after the implementation of the programmes. Interventions focusing on training and educating caregivers (n = 14) and cognitive–behavioural strategies (n = 7) were the most common, while programmes focusing on emotional and psychological support as a resource to improve caregivers’ psychological outcomes were scarce. Conclusions: This systematic review adds to the growing body of evidence and insight showing that programmes that address informal caregivers’ needs seem to contribute to better physical and psychological health outcomes through the promotion of caregivers’ educational support and the implementation of cognitive–behavioural strategies. Future research should implement methodologically robust cross-country programmes tailored to informal caregivers’ physical, emotional, psychosocial, societal, and educational needs throughout the care trajectory. Full article

College students are a primary population for risky alcohol use behaviors, with one of every eleven students grappling with severe alcohol-related issues. The objective of this scoping review was to synthesize the existing literature to identify factors influencing the prevalence of drinking and driving (DAD) behaviors among college students. A scoping review was conducted using Medline (PubMed), ERIC, The American Journal on Addictions, and the NCHA databases. Criteria for article selection included being published in English and focused on DAD behaviors among college students. Articles excluded from the review were systematic reviews and discussion pieces without empirical findings related to college DAD. Of the included studies (n = 23), most identified a range of factors as being influential in college students’ DAD behavior including a family history of alcohol misuse, the use of other substances such as marijuana, age of initial alcohol consumption, place of residence, propensity for sensation seeking, affiliation with sorority/fraternity groups, and the perception of associated risks. Effective strategies may include education on the risks of combined alcohol and substance use, screening and brief interventions tailored to at-risk students, and the implementation of campus policies that promote responsible alcohol consumption and deter DAD. Full article