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The elemental composition of chemical elements can vary between healthy and diseased tissues, providing essential insights into metabolic processes in physiological and diseased states. This study aimed to evaluate the calcium (Ca) and phosphorus (P) levels in the bones of rats with/without streptozotocin-induced diabetes and/or exposure to infrasound. X-ray fluorescence spectroscopy was used to determine the concentrations of Ca and P in Wistar rat tibiae samples.The results showed a significant decrease in bone P concentration in streptozotocin-induced diabetic rats compared to untreated animals. Similarly, the Ca/P ratio was higher in the streptozotocin-induced diabetic group. No significant differences were observed in bone Ca concentration between the studied groups or between animals exposed and not exposed to infrasound.Moreover, streptozotocin-induced diabetic rats had lower bone P concentration but unaltered bone Ca concentration compared to untreated rats. Infrasound exposure did not impact bone Ca or P levels. The reduced bone P concentration may be associated with an increased risk of bone fractures in diabetes.

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In the context of marine litter monitoring, reporting the weight of beached litter can contribute to a better understanding of pollution sources and support clean-up activities. However, the litter scaling task requires considerable effort and specific equipment. This experimental study proposes and evaluates three methods to estimate beached litter weight from aerial images, employing different levels of litter categorization. The most promising approach (accuracy of 80 %) combined the outcomes of manual image screening with a generalized litter mean weight (14 g) derived from studies in the literature. Although the other two methods returned values of the same magnitude as the ground-truth, they were found less feasible for the aim. This study represents the first attempt to assess marine litter weight using remote sensing technology. Considering the exploratory nature of this study, further research is needed to enhance the reliability and robustness of the methods.

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The abundance of beach litter has been increasing globally during the last decades, and it is an issue of global concern. A new survey strategy, based on uncrewed aerial vehicles (UAV, aka drones), has been recently adopted to improve the monitoring of beach macro-litter items abundance and distribution. This work identified and analysed the 15 studies that used drone for beach litter surveys on an operational basis. The analysis of technical parameters for drone flight deployment revealed that flight altitude varied between 5 and 40 m. The analysis of final assessments showed that, through manual and/or automated items detection on images, most of studies provided litter bulk characteristics (type, material and size), along with litter distribution maps. The potential standardization of drone-based litter survey would allow a comparison among surveys, however it seems difficult to propose a standard set of flight parameters, given the wide variety of coastal environments, the different devices available, and the diverse objectives of drone-based litter surveys. On the other hand, in our view, a set of common outcomes can be proposed, based on the grid mapping process, which can be easily generated following the procedure indicated in the paper. This work sets the ground for the development of a standardized protocol for drone litter data collection, analysis and assessments. This would allow the provision of broad scale comparative studies to support coastal management at both national and international scales.

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A vast number of adhesive formulations exist currently. However, available adhesives still have several drawbacks such as increased hydrophilicity, polymerization deficiency, potential cytotoxicity and limited monomer interdiffusion within dentin. To improve material properties, a Bisphenol A-free adhesive containing a novel dendrimer G(2)-isocyanatoethyl methacrylate (G-IEMA) in replacement of Bis-GMA was made and tested. Sound human molars were sectioned to expose mid-coronal dentin, which was bonded using four adhesives­Futurabond, Scotchbond Universal and experimentals EM1 and EM2. The experimental adhesive EM2 contained G-IEMA, while EM1 had Bis-GMA. Groups were further allocated to two different adhesive strategies: etch-and-rinse (20 s etching) or self-etch. Immediate (24 h) microtensile bond strength to dentin (n = 5) was tested using a universal testing machine (1 mm/min, 5 kN; Shimadzu AGS-X Autograph, Tokyo, Japan), while the ultrastructure of the interface (n = 2) was assessed using scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS). Nanoleakage expression was evaluated using silver nitrate penetration and posterior SEM-EDS analysis (n = 3). Linear mixed models/Generalized models were used for inferential statistics (5% significance level). Bond strength results did not depend on the adhesive choice, although differences were found between strategies (p < 0.001). Regarding nanoleakage, when applied in an etch-and-rinse mode, experimental adhesives scored lower nanoleakage means than Futurabond and Scotchbond Universal. The novel adhesive shows interesting interfacial properties, with favorable nanoleakage results and a bond strength to dentin that matches current commercial adhesives.

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The emergence of carbapenemase-producing Klebsiella pneumoniae strains has triggered the use of old antibiotics such as colistin. This is driving the emergence of colistin resistance in multidrug-resistant strains that underlie life-threatening infections. This study analyses the mutational diversity of 22 genes associated with colistin resistance in 140 K. pneumoniae clinical isolates integrated in a high-resolution phylogenetic scenario. Colistin susceptibility was accessed by broth microdilution. A total of 98 isolates were susceptible and 16 were resistant, 10 of which were carbapenemase producers. Across the 22 genes examined, 171 non-synonymous mutations and 9 mutations associated with promoter regions were found. Eighty-five isolates had a truncation and/or deletion in at least one of the 22 genes. However, only seven mutations, the complete deletion of mgrB or insertion sequence (IS)-mediated disruption, were exclusively observed in resistant isolates. Four of these (mgrBIle13fs, pmrBGly207Asp, phoQHis339Asp and ramAIle28Met) comprised novel mutations that are potentially involved in colistin resistance. One strain bore a ISEcp1-blaCTX-M-15::mgrB disruption, underlying co-resistance to third-generation cephalosporins and colistin. Moreover, the high-resolution phylogenetic context shows that most of the mutational diversity spans multiple phylogenetic clades, and most of the mutations previously associated with colistin resistance are clade-associated and present in susceptible isolates, showing no correlation with colistin resistance. In conclusion, the present study provides relevant data on the genetic background of genes involved with colistin resistance deeply rooted across monophyletic groups and provides a better understanding of the genes and mutations involved in colistin resistance.

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In Portugal, data on mortality rate attributed to household and ambient air pollution are not reported due to shortness and irregularity of the available data series, and therefore, the disclosure of the national progress in reducing the number of deaths and illnesses from air contamination in exposures to multiple pollutants is incomplete. The present work describes the application of the AirQ+ model developed by the WHO to calculate how much of specific health outcomes is attributable to long-term exposure to atmospheric NO2, PM2.5, and O3 in the population of various municipalities in Portugal, from 2010 to 2019. Linear Mixed Models were used for data analysis and have shown that (i) approximately 5000 deaths per year are attributable to exposure to mixtures of NO2 and PM2.5; (ii) the spatial distribution of the proportion of deaths attributable to NO2, PM2.5 and O3 shows significant differences between locations, and (iii) that AirQ+ is a useful tool for the purpose of effective Public Health policymaking and reporting on the national progress to implement the 2030 Agenda.

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Ainda não existe consenso a respeito da prescrição de testosterona terapêutica para mulheres cisgênero na menopausa, seus benefícios e efeitos colaterais. Objetivo: Sumarizar os estudos recentes sobre o uso terapêutico da testosterona em mulheres na menopausa. Método: Revisão sistemática de literatura baseada nos dados da plataforma PubMed. Foram identificados 10.912 estudos potenciais. As palavras-chave usadas foram "testosterone", "women", "therapy", "treatment". Selecionou-se revisões sistemáticas e metanálises dos últimos 5 anos, todas na língua inglesa. Excluiram-se artigos duplicados, os que abordam uso de testosterona como anabolizantes e/ou em atletas e em transexuais e estudos que envolviam homens. O levantamento de dados foi realizado com 9 artigos. Resultados: O uso dessa terapia hormonal no período da pós-menopausa mostrou melhora dos sintomas sexuais. Há diferença entre as vias de aplicação, sendo que a via oral pode acarretar maiores prejuízos, principalmente em relação aos níveis lipídicos séricos. A testosterona intravaginal melhora a função sexual. A prescrição na prática se mostra um problema, pois as apresentações comercializadas não atendem à necessidade fisiológica feminina. Conclusão: A terapia mostra-se eficaz em curto prazo, apesar de ainda haver necessidade de estudos para uso em longo prazo

There is still no consensus regarding the prescription of testosterone therapy for cisgender menopausal woman, its benefits and side effects. Objective: Summarize recent studies on the therapeutic use of testosterone in menopausal woman. Methods: Systematic literature review based on data from the PubMed platform. A total of 10.912 potential studies were identified. The used keywords were "testosterone", "woman", "therapy", "treatment". Systematic reviews and meta-analyses from the last 5 years were selected, all in English. Were excluded: duplicated articles, the ones that address the use of testosterone as anabolic steroid and/or in athletes and transsexuals and studies that involved man. Tthe data collection was made with 9 articles. Results: The use of this hormone therapy in postmenopausal period showed sexual symptoms improvement. There are differences between the routes of administration, for the oral administration could lead to more damage, mainly related to the lipids serum levels. Intravaginal testosterone improves sexual function. The prescription in practice is shown to be a problem, since the commercialized presentations do not meet the feminine physiological necessities. Conclusion: This therapy proves to be effective in short term use, although there is still a need for studies for long-term use

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Introdução: A intolerância à lactose é síndrome decorrente da má digestão do dissacarídeo lactose por deficiência da enzima lactase, gerando sintomas principalmente gastrintestinais. Ela envolve 4 causas principais: deficiência congênita de lactase; deficiência de lactase de desenvolvimento; intolerância primária à lactose; e deficiência secundária à lactase. Objetivo: Revisão da apresentação clínica da intolerância à lactose e os principais métodos disponíveis para seu diagnóstico clínico. Método: Revisão narrativa da base de dados PubMed, por meio das palavras-chave "lactose intolerance" e "genetic test" utilizando o descritor boleano and. Foram incluídos somente artigos em língua inglesa e publicados entre os anos de 2017 e 2022, totalizando 8 artigos. Resultado: O diagnóstico de intolerância à lactose relaciona-se com o seu tipo e utiliza-se dos principais métodos: teste oral de tolerância à lactose, teste genético, teste do hidrogênio expirado. Conclusão: Quanto aos métodos de diagnóstico, o teste do hidrogênio expirado é o de escolha, por não ser invasivo, possuir execução fácil e baixo custo. Entretanto, ele não dispensa associação com outras técnicas diagnósticas. O teste genético também é muito útil e sua vantagem é que não há necessidade da realização do teste oral de tolerância.

Introduction: Lactose intolerance is a syndrome resulting from maldigestion of the disaccharide lactose due to lactase enzyme deficiency causing symptoms mainly gastrointestinal. It involves 4 main causes: congenital lactase deficiency; developmental lactase deficiency; primary lactose intolerance; and secondary lactase deficiency. Objective: Review of the clinical presentation of lactose intolerance and the main methods available for its clinical diagnosis. Methods: Literature review in the PubMed database, using the keywords "lactose intolerance" and "genetic test" and using the Boolean data type and. Only articles in English and published between the years 2017 and 2022 were included, totalizing 8 articles. Results: The diagnosis of lactose intolerance is related to its type and uses the main diagnostic tests: oral lactose tolerance, genetic, expired hydrogen. Conclusion: Regarding diagnostic methods, the expired hydrogen test is the one of choice, as it is not invasive, is easy to perform and has low cost. However, it does not dispense association with other diagnostic techniques. Genetic testing is also very usefull and its advantage is that there is no need to use the oral lactose tolerance test.

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The emergence of multidrug resistant Gram-negative pathogens, particularly carbapenemase producers, has forced clinicians to use last line antibiotics, such as colistin. Since colistin susceptibility testing presents several challenges, this study aimed at evaluating the performance of two alternative susceptibility methods for Klebsiella pneumoniae, namely, agar dilution (AD) and MIC test strips (MTS). These approaches were compared with the reference method, broth microdilution (BMD), and provide a quantitative description for the "skipped well" (SW) phenomenon. Colistin susceptibility was evaluated by BMD and AD in parallel and triplicate, using 141 K. pneumoniae clinical isolates while MTS performance was evaluated only for a subset (n = 121). Minimum inhibitory concentration analysis revealed that a substantial part (n = 26/141; 18.4%) of the initial isolates was deemed undetermined by BMD due to the following: discordance between replicates (1.4%); presence of multiple SWs (7.8%); and the combination of both events (9.2%). Both AD and MTS revealed a high number of false-susceptible strains ("very major errors"), 37.5% and 68.8%, respectively. However, AD agreement indices were reasonably high (EA = 71.3% and CA = 94.8%). For MTS these indices were lower, in particular EA (EA = 41.7% and CA = 89.6), but the approach enabled the detection of distinct sub-populations for four isolates. In conclusion, this study provides the most comprehensive study on the performance of AD and MTS for colistin susceptibility testing in K. pneumoniae, highlighting its limitations, and stressing the importance of sample size and composition. Further, this study highlights the impact of the SW phenomenon associated with the BMD method for K. pneumoniae.

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Klebsiella pneumoniae is an increasing threat to public health and represents one of the most concerning pathogens involved in life-threatening infections. The resistant and virulence determinants are coded by mobile genetic elements which can easily spread between bacteria populations and co-evolve with its genomic host. In this study, we present the full genomic sequences, insertion sites and phylogenetic analysis of 150 prophages found in 40 K. pneumoniae clinical isolates obtained from an outbreak in a Portuguese hospital. All strains harbored at least one prophage and we identified 104 intact prophages (69.3%). The prophage size ranges from 29.7 to 50.6 kbp, coding between 32 and 78 putative genes. The prophage GC content is 51.2%, lower than the average GC content of 57.1% in K. pneumoniae. Complete prophages were classified into three families in the order Caudolovirales: Myoviridae (59.6%), Siphoviridae (38.5%) and Podoviridae (1.9%). In addition, an alignment and phylogenetic analysis revealed nine distinct clusters. Evidence of recombination was detected within the genome of some prophages but, in most cases, proteins involved in viral structure, transcription, replication and regulation (lysogenic/lysis) were maintained. These results support the knowledge that prophages are diverse and widely disseminated in K. pneumoniae genomes, contributing to the evolution of this species and conferring additional phenotypes. Moreover, we identified K. pneumoniae prophages in a set of endolysin genes, which were found to code for proteins with lysozyme activity, cleaving the ß-1,4 linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in the peptidoglycan network and thus representing genes with the potential for lysin phage therapy.

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Biofilm formation has been shown to be critical to the success of uropathogens. Although Staphylococcus saprophyticus is a common cause of urinary tract infections, its biofilm production capacity, composition, genetic basis, and origin are poorly understood. We investigated biofilm formation in a large and diverse collection of S. saprophyticus (n = 422). Biofilm matrix composition was assessed in representative strains (n = 63) belonging to two main S. saprophyticus lineages (G and S) recovered from human infection, colonization, and food-related environment using biofilm detachment approach. To identify factors that could be associated with biofilm formation and structure variation, we used a pangenome-wide association study approach. Almost all the isolates (91%; n = 384/422) produced biofilm. Among the 63 representative strains, we identified eight biofilm matrix phenotypes, but the most common were composed of protein or protein-extracellular DNA (eDNA)-polysaccharides (38%, 24/63 each). Biofilms containing protein-eDNA-polysaccharides were linked to lineage G and environmental isolates, whereas protein-based biofilms were produced by lineage S and infection isolates (p < 0.05). Putative biofilm-associated genes, namely, aas, atl, ebpS, uafA, sasF, sasD, sdrH, splE, sdrE, sdrC, sraP, and ica genes, were found with different frequencies (3-100%), but there was no correlation between their presence and biofilm production or matrix types. Notably, icaC_1 was ubiquitous in the collection, while icaR was lineage G-associated, and only four strains carried a complete ica gene cluster (icaADBCR) except one that was without icaR. We provided evidence, using a comparative genomic approach, that the complete icaADBCR cluster was acquired multiple times by S. saprophyticus and originated from other coagulase-negative staphylococci. Overall, the composition of S. saprophyticus biofilms was distinct in environmental and clinical isolates, suggesting that modulation of biofilm structure could be a key step in the pathogenicity of these bacteria. Moreover, biofilm production in S. saprophyticus is ica-independent, and the complete icaADBCR was acquired from other staphylococci.

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Unmanned aerial systems (UAS, aka drones) are being used to map macro-litter on the environment. Sixteen qualified researchers (operators), with different expertise and nationalities, were invited to identify, mark and categorize the litter items (manual image screening, MS) on three UAS images collected at two beaches. The coefficient of concordance (W) among operators varied between 0.5 and 0.7, depending on the litter parameter (type, material and colour) considered. Highest agreement was obtained for the type of items marked on the highest resolution image, among experts in litter surveys (W = 0.86), and within territorial subgroups (W = 0.85). Therefore, for a detailed categorization of litter on the environment, the MS should be performed by experienced and local operators, familiar with the most common type of litter present in the target area. This work provides insights for future operational improvements and optimizations of UAS-based images analysis to survey environmental pollution.

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Staphylococcus saprophyticus is a common pathogen of the urinary tract, a heavy metal-rich environment, but information regarding its heavy metal resistance is unknown. We investigated 422 S. saprophyticus isolates from human infection and colonization/contamination, animals, and environmental sources for resistance to copper, zinc, arsenic, and cadmium using the agar dilution method. To identify the genes associated with metal resistance and assess possible links to pathogenicity, we accessed the whole-genome sequence of all isolates and used in silico and pangenome-wide association approaches. The MIC values for copper and zinc were uniformly high (1,600 mg/liter). Genes encoding copper efflux pumps (copA, copB, copZ, mco, and csoR) and zinc transporters (zinT, czrAB, znuBC, and zur) were abundant in the population (20 to 100%). Arsenic and cadmium showed various susceptibility levels. Genes encoding the ars operon (arsRDABC), an ABC transporter and a two-component permease, were linked to resistance to arsenic (MICs ≥ 1,600 mg/liter; 14% [58/422]; P < 0.05). At least three cad genes (cadA or cadC and cadD-cadX or czrC) and genes encoding multidrug efflux pumps and hyperosmoregulation in acidified conditions were associated with resistance to cadmium (MICs ≥ 200 mg/liter; 20% [85/422]; P < 0.05). These resistance genes were frequently carried by mobile genetic elements. Resistance to arsenic and cadmium were linked to human infection and a clonal lineage originating in animals (P < 0.05). Altogether, S. saprophyticus was highly resistant to heavy metals and accumulated multiple metal resistance determinants. The highest arsenic and cadmium resistance levels were associated with infection, suggesting resistance to these metals is relevant for S. saprophyticus pathogenicity.

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A patient with previous CABG was hospitalized for fever and Staphylococcus aureus bacteraemia without cardiac involvement. After appropriate antibiotic cycle, the patient recovered and was discharged. Six months later, symptoms and bacteraemia relapsed. A small intriguing 'cystic' mass was visualized in the right atrium by echocardiography. Once again, was discharged after successful antibiotic treatment. Four months later, symptoms and Staphylococcus bacteraemia reappeared with increasing mass size and surgery was decided. Intraoperatively, it was perceived that the mass was related to an epicardial pacemaker wire. Retained epicardial wires should be remembered in endocarditis evaluation.

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Few studies have explored the impacts of COVID-19 and lockdown on the mental health of undergraduate nursing students. This study aimed: a) to explore perceived stress among undergraduate nursing students in Portugal and Spain during the COVID-19 pandemic outbreak; and b) to analyze several COVID-19 related factors and psychological issues that may be associated with perceived stress. A cross-sectional study was conducted with a convenience sample of Portuguese and Spanish undergraduate nursing students (n=1075). The data gathered included demographic information, questions about COVID-19 related factors, and psychological issues. Data were analyzed using multiple logistic regression with a degree of significance at p<0.05. High perceived stress scores were found in 558 participants (51.9%). Students with high perceived stress most likely had a COVID-19 diagnosis in their household; their household income had been affected by the COVID-19 pandemic; experienced difficulty falling asleep or sleeping all night; consumed junk food in excess; neglected their appearance; felt headaches, stomach aches, and back pain; and lacked the patience or desire to exercise. Additionally, high perceived stress was negatively associated with life satisfaction. The results provide evidence that infectious diseases, such as COVID-19, may significantly influence mental health. Further research should explore the long-term psychological effects of the COVID-19 pandemic among nursing students.

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A wealth of studies focusing on the relationships between negative health outcomes and short-term and long-term exposures to environmental risk factors have produced estimates of the burden of disease attributable to air pollution, which have led to the implementation of air pollution control strategies. However, the call to expand those studies, in terms of geographical units of analysis to produce more accurate estimates of the burden of disease in the different countries has been made. Studies of the specific environment-health relationship concerning air pollution in Portugal are scarce and rather descriptive. Therefore, this work assesses the trends both in atmospheric levels of pollutants including particulate matter (PM10), ozone (O3), nitrogen dioxide (NO2) and sulphur dioxide (SO2), and in mortality rates for diabetes, malignant neoplasms and diseases of the respiratory, digestive and circulatory systems, and explores the links between exposure to air pollutants and mortality, following proposed biological pathways and using inferential statistics methods, for the period 2010 to 2017 in Portugal. The following major conclusions were drawn: (i) despite a somewhat initial downward trend in PM10 and a peak in O3 levels, fairly constant air pollution levels were mostly observed; (ii) concomitantly, increases in age-adjusted mortality rates were significant for all diseases except diabetes; (iii) lower atmospheric levels of pollutants were observed in rural areas, when compared to urban areas, except for ozone; (iv) age-adjusted mortality rates were higher in rural regions, for diabetes, and in urban regions, for malignant neoplasms; (v) for a 10 µg/m3 increase in atmospheric levels of PM10, regression analysis estimated an increase of 0.30% in the mortality rate for diseases of the respiratory, digestive and circulatory systems, and malignant neoplasms combined.

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