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Water pollution and antimicrobial resistance (AMR) have become two global threats; 80% of diseases and 50% of child deaths are due to poor water quality. In this study, hydrothermal processing was employed to manufacture manganese oxide nanorods. Silver dopant was deposited on the surface of manganese oxide. XRD diffractogram confirmed the facile synthesis of Ag/Mn2O3 nanocomposite. XPS survey analysis demonstrated silver content of 9.43 atom %. Photocatalytic measurements demonstrated the outstanding efficiency of the Ag-Mn2O3 compared to virgin oxide particles under visible radiation. Degradation efficiencies Mn2O3 and Ag/Mn2O3 on methyl orange (MO) dye was found to be 53% and 85% under visible spectrum. Silver dopant was found to decrease the binding energy of valence electrons; this action could support electron-hole pair generation under visible spectrum and could promote catalytic performance. Ag/Mn2O3 NPs demonstrated most effective performance (95% removal efficiency) at pH 3; this could be ascribed to the electrostatic attraction between positively charged catalyst and the negatively charged MO. Ag/Mn2O3 demonstrated enhanced antibacterial activity against Gram-positive Staphylococcus aureus (S. aureus) (19 mm ZOI), and Gram-negative Escherichia coli (E. coli) (22 mm ZOI) respectively; the developed nanocomposite demonstrated advanced anti-film activity with inhibition percentage of 95.5% against E. coli followed by 89.5% against S. aureus.
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Escherichia coli , Compostos de Manganês , Nanocompostos , Óxidos , Prata , Staphylococcus aureus , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Óxidos/química , Óxidos/farmacologia , Prata/química , Prata/farmacologia , Nanocompostos/química , Catálise , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Luz , Compostos Azo/química , Compostos Azo/farmacologia , Testes de Sensibilidade Microbiana , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/síntese química , Processos FotoquímicosRESUMO
Seaweeds are recognised as a potential eco-friendly food source. However, some species have shown the capacity to bioaccumulate many substances of diverse nature, such as inorganic nanoparticles (NPs), which may have potentially harmful effects on them. Among these NPs, silver nanoparticles (AgNPs) have been used to enhance the antifungal and antibacterial properties of the final consumer products, such as textiles and food packages. Their potential release into the aquatic environment raises significant concern, increasing the probability of interaction with aquatic biota, such as macroalgae. In this work, we investigated the differences in bioaccumulation, biodistribution, and transformation of NPs as a function of seaweed species. We selected polyvinylpyrrolidone-coated silver nanoparticles (PVP-AgNPs) as model NP since they remain colloidally stable in seawater, focusing the study only on single particles and not on aggregates. The study was conducted on two different seaweed species with high commercial interest and value as human food: the red seaweed Palmaria palmata and the green seaweed Ulva fenestrata. Single-particle inductively coupled plasma mass spectroscopy (spICP-MS) analysis showed high and similar bioaccumulation of PVP-AgNPs in both seaweeds, in the range of 109 NPs/g of seaweed. However, electron microscopy with energy-dispersive X-ray analysis demonstrated that their time-dependent distribution and transformation in the algal tissue, mainly dissolution and formation of sulfur-rich corona and/or sulfidation, highly depended on the seaweed type. These results indicate that special attention should be given to the presence and transformation of AgNPs in seaweeds intended for human consumption. Not only the dissolution degree but also the speciation of these NPs could heavily impact their bioaccessibility, bioavailability, biodistribution, and toxicity to humans after ingestion.
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Algas Comestíveis , Nanopartículas Metálicas , Povidona , Prata , Poluentes Químicos da Água , Bioacumulação , Algas Comestíveis/química , Algas Comestíveis/metabolismo , Nanopartículas Metálicas/química , Povidona/química , Povidona/metabolismo , Prata/química , Prata/metabolismo , Distribuição Tecidual , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/análiseRESUMO
Pathologic narcissism (PN) and narcissistic personality disorder (NPD) are 2 common and stigmatized clinical constructs that are known to have large consequences for patients' functioning and mental health-related outcomes. To date, no treatment for these conditions has been empirically validated, but there is a relative consensus about the importance of psychoeducation. Here we present a model for a psychoeducational intervention for patients with PN or NPD. We start with a review of the current evidence on the role of psychoeducation in different treatment models for PN, and we discuss several aspects regarding the content and format of this type of intervention. Based on this review, we outline a 6-week Good Psychiatric Management-based psychoeducation group program that we developed. We also describe how such a psychoeducational intervention can be implemented individually, with fewer resources, in general care settings. Finally, we discuss the strengths and limitations of our approach and elaborate on the rationale for our proposal. We believe that this program proposal is a first step in the development of psychoeducational programs for PN and NPD that can be further corrected and enhanced.
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Narcisismo , Transtornos da Personalidade , Psicoterapia de Grupo , Humanos , Transtornos da Personalidade/terapia , Psicoterapia de Grupo/métodos , Educação de Pacientes como Assunto/métodos , Transtorno da Personalidade NarcisísticaRESUMO
INTRODUCTION: Pathological narcissism (PN) can be defined as the compromised and fluctuating ability to regulate self-esteem, the latter depending on external validation, admiration, or enhancement, all resulting in grandiose (e.g., self-enhancement, aggressiveness, manipulation) or vulnerable (e.g., depression, anxiety, self-criticism, avoidance) dysfunctional reactions when confronting with self-esteem threats. A link has been suggested between PN and emotion dysregulation (ED), but to date, no systematic review has been conducted. METHODS: We conducted a systematic review of the literature published until February 2024 studying the association between PN (with or without a diagnosis of narcissistic personality disorder) and ED, divided in two domains: emotion regulation difficulties and strategies. RESULTS: Twenty-two studies were included in our analysis. Altogether, the available data are insufficient to conclude on the link between grandiose narcissism and emotion regulation difficulties in non-clinical population (notably due to different patterns of associations depending on the scale used to assess narcissism). However, the small number of studies conducted in clinical population seems to indicate a possible absence of association between the two constructs. On the other side, there is considerable evidence for the existence of a positive association between vulnerable narcissism and emotion regulation difficulties, regardless of the scale used to assess narcissism and the type of population considered. Finally, regarding emotion regulation strategies, data are too scarce to draw any conclusion, even though there seems to be a trend toward positive association between narcissistic vulnerability and expressive suppression. CONCLUSION: ED seems to be highly associated with narcissistic vulnerability. Given that every patient suffering from PN may experience vulnerable states, we believe that ED should be considered as an important part of psychoeducation programs and psychotherapeutic treatments designed for this population.
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DNA origami is an emerging technology that can be used as a nanoscale platform in numerous applications ranging from drug delivery systems to biosensors. The DNA nanostructures are assembled from large single-stranded DNA (ssDNA) scaffolds, ranging from hundreds to thousands of nucleotides and from short staple strands. Scaffolds are usually obtained by asymmetric PCR (aPCR) or Escherichia coli infection/transformation with phages or phagemids. Scaffold quantification is typically based on agarose gel electrophoresis densitometry for molecules obtained by aPCR, or by UV absorbance, in the case of scaffolds obtained by infection or transformation. Although these methods are well-established and easy-to-apply, the results obtained are often inaccurate due to the lack of selectivity and sensitivity in the presence of impurities. Herein, we present an HPLC method based on ion-pair reversed-phase (IP-RP) chromatography to quantify DNA scaffolds. Using IP-RP chromatography, ssDNA products (449 and 1000 nt) prepared by aPCR were separated from impurities and from the double stranded (ds) DNA byproduct. Additionally, both ss and dsDNA were quantified with high accuracy. The method was used to guide the optimization of the production of ssDNA by aPCR, which targeted the maximization of the ratio of ssDNA to dsDNA obtained. Moreover, ssDNA produced from phage infection of E. coli cells was also quantified by IP-RP using commercial ssDNA from the M13mp18 phage as a standard.
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The search for affordable enzymes with exceptional characteristics is fundamental to overcoming industrial and environmental constraints. In this study, a recombinant GH10 xylanase (Xyn10-HB) from the extremely alkaliphilic bacterium Halalkalibacterium halodurans C-125 cultivated at pH 10 was cloned and expressed in E. coli BL21(DE3). Removal of the signal peptide improved the expression, and an overall activity of 8 U/mL was obtained in the cell-free supernatant. The molecular weight of purified Xyn10-HB was estimated to be 42.6 kDa by SDS-PAGE. The enzyme was active across a wide pH range (5-10) with optimal activity recorded at pH 8.5 and 60 °C. It also presented good stability with a half-life of 3 h under these conditions. Substrate specificity studies showed that Xyn10-HB is a cellulase-free enzyme that conventionally hydrolyse birchwood and oat spelts xylans (Apparent Km of 0.46 mg/mL and 0.54 mg/mL, respectively). HPLC analysis showed that both xylans hydrolysis produced xylooligosaccharides (XOS) with a degree of polymerization (DP) ranging from 2 to 9. The conversion yield was 77% after 24 h with xylobiose and xylotriose as the main end-reaction products. When assayed on alkali-extracted wheat straw heteroxylan, the Xyn10-HB produced active XOS with antioxidant activity determined by the DPPH radical scavenging method (IC50 of 0.54 mg/mL after 4 h). Owing to its various characteristics, Xyn10-HB xylanase is a promising candidate for multiple biotechnological applications.
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Endo-1,4-beta-Xilanases , Proteínas Recombinantes , Xilanos , Especificidade por Substrato , Hidrólise , Xilanos/metabolismo , Endo-1,4-beta-Xilanases/metabolismo , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Escherichia coli/genética , Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio , Clonagem Molecular , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Glucuronatos/metabolismo , Estabilidade Enzimática , Cinética , Peso Molecular , Oligossacarídeos/metabolismo , DissacarídeosRESUMO
Pathological narcissism (PN) is a common psychopathological issue leading to maladaptive strategies to cope with self-esteem threats, including self-enhancement and exploitation (grandiose strategies) or internalized shame, depression, and social withdrawal (vulnerable strategies). Mentalizing is a key process for regulating self and other representations and their associated emotions. Patients with PN further struggle with emotion dysregulation (ED), which during development is intertwined with the growing capacity to mentalize. We seek to contribute to emerging empirical data documenting the associations between PN and ED and between PN and mentalizing, and to provide information on the nature of their mutual relationships. In the present study, we assessed PN, ED, and three mentalizing dimensions (mentalizing self, other, and motivation to mentalize) in 183 patients consulting in our outpatient unit specialized in ED. We found that narcissistic vulnerability was negatively associated with self-mentalizing and positively associated with overall ED, both even after adjustment for borderline and attention deficit hyperactivity disorder (ADHD) symptoms. However, the association with ED was not maintained after further adjustment for self-mentalizing or overall-mentalizing, which suggests that mentalizing may play a mediating role in this relationship. On the other hand, narcissistic grandiosity was positively associated with other-mentalizing and ED and negatively associated with self-mentalizing in bivariate analyses, but these last two associations were not maintained after adjustment for comorbid borderline and/or ADHD symptomatology. This study provides new information on the link between PN and ED and on key mentalizing dimensions meaningfully relating to PN, notably through a potential role of self-mentalizing processes between PN and ED.
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Regulação Emocional , Transtorno da Personalidade Narcisística , Autoimagem , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Sintomas Afetivos , Transtorno do Deficit de Atenção com Hiperatividade , Regulação Emocional/fisiologia , Mentalização/fisiologia , Transtorno da Personalidade Narcisística/psicologiaRESUMO
The quest for environmentally sustainable materials spans many fields and applications including optical materials. Here, we present the development of light filters using a gelatin-based nanocomposite. Owing to the plasmonic properties of metallic nanoparticles (NPs), strong light-matter interactions, these filters can be customized across the UV-Visible-NIR spectrum. The filters are designed for modular use, allowing for the addition or removal of desired spectral ranges. Moreover, the nanocomposites are composed of biodegradable and biocompatible materials which highlight the intersection of chemistry and ecological awareness for the exploration of new eco-friendly alternatives. These plasmonic gelatin-based filters block light due to the Localized Surface Plasmon Resonance (LSPR) of the NPs and can be tailored to meet various requirements, akin to a diner selecting options from a menu. This approach is inspired by culinary techniques, and we anticipate it will stimulate further exploration of biomaterials for applications in optics, materials science or electronics.
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Adult attention deficit hyperactivity disorder (ADHD) is often associated with personality pathology. However, only few studies have been conducted on the link between ADHD and pathological narcissism (PN), with or without a diagnosis of narcissistic personality disorder (NPD). In order to fill this gap, PN and NPD were assessed in 164 subjects suffering from ADHD, with several other measures including ADHD severity, quality of life, depression, anxiety, impulsivity, and emotion dysregulation (ED). We found that a significant proportion of ADHD patients suffered from NPD, and that both narcissistic grandiosity and vulnerability were associated with ADHD hyperactivity and impulsivity symptoms, but not with inattentive symptoms. These two dimensions seemed to be negatively associated with well-being and positively associated with most of the other studied psychiatric dimensions except ED, the latter being only associated with vulnerability, even after adjustment on borderline symptoms. Overall, despite important limitations that limit the generalizability of our findings to the overall ADHD population (notably linked to selection bias), we believe that this exploratory study sheds light on the potential clinical relevance of narcissistic pathology in adult ADHD patients.
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Transtorno do Deficit de Atenção com Hiperatividade , Narcisismo , Transtornos da Personalidade , Humanos , Adulto , Masculino , Feminino , Transtornos da Personalidade/epidemiologia , Estudos Retrospectivos , Escalas de Graduação Psiquiátrica , Adulto Jovem , Pessoa de Meia-Idade , Qualidade de Vida , Comportamento Impulsivo/fisiologia , Transtorno da Personalidade NarcisísticaRESUMO
MicroRNA (miRNA) modulation has been identified as a promising strategy for improving the response of human prostate cancer (PCa) to radiotherapy (RT). Studies have shown that mimics or inhibitors of miRNAs could modulate the sensitivity of PCa cells to RT. In addition, pegylated gold nanoparticles have been studied as a therapeutic approach to treat PCa cells and/or vehicles for carrying miRNAs to the inside of cells. Therefore, we evaluated the capacity of hypofractionated RT and pegylated gold nanorods (AuNPr-PEG) to modulate the miRNA signature on PCa cells. Thus, RT-qPCR was used to analyze miRNA-95, miRNA-106-5p, miRNA-145-5p, and miRNA-541-3p on three human metastatic prostate cell lines (PC3, DU145, and LNCaP) and one human prostate epithelial cell line (HprEpiC, a non-tumor cell line) with and without treatment. Our results showed that miRNA expression levels depend on cell type and the treatment combination applied using RT and AuNPr-PEG. In addition, cells pre-treated with AuNPr-PEG and submitted to 2.5 Gy per day for 3 days decreased the expression levels of miRNA-95, miRNA-106, miRNA-145, and miRNA-541-3p. In conclusion, PCa patients submitted to hypofractionated RT could receive personalized treatment based on their metastatic cellular miRNA signature, and AuNPr-PEG could be used to increase metastatic cell radiosensitivity.
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Nanopartículas Metálicas , MicroRNAs , Neoplasias da Próstata , Masculino , Humanos , MicroRNAs/genética , Ouro/metabolismo , Linhagem Celular Tumoral , Neoplasias da Próstata/metabolismo , Polietilenoglicóis/metabolismo , Regulação Neoplásica da Expressão GênicaRESUMO
Emotion dysregulation (ED) has primarily been described in patients suffering from borderline personality disorder (BPD) and is an integral part of this diagnosis, but it is also a transdiagnostic construct that can be found in several other psychiatric disorders. The strong relationships between ED and BPD may lead clinicians to underestimate ED associated to other clinical contexts. This can lead to difficulties in diagnostic and treatment orientation, especially in the context of comorbidities. In this article, after reviewing the literature on the development and functioning of emotion dysregulation, and on the evidence for emotion dysregulation in eight disorders (borderline personality disorder, pathological narcissism with/without narcissistic personality disorder, obsessive-compulsive personality disorder, antisocial personality disorder, bipolar disorder, autism spectrum disorder, complex post-traumatic stress disorder, and adult attention deficit hyperactivity disorder), we present a transdiagnostic processual model of emotion dysregulation based on core triggers and interpersonal styles to try to address this issue and to provide a simple but technical tool to help clinicians in their diagnostic assessment and treatment orientation. By focusing more on typical patterns and interpersonal dynamics than only on categories, we believe that this model may contribute to the actual need for improvement of our current psychiatric classifications, alongside other well-studied and under-used dimensional models of psychopathology (e.g., HiTOP, AMPD), and may be useful to build more specific treatment frameworks for patients suffering from ED.
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Biosynthetic gold nanoparticles (bAuNPs) present a promising avenue for enhancing bio-compatibility and offering an economically and environmentally responsible alternative to traditional production methods, achieved through a reduction in the use of hazardous chemicals. While the potential of bAuNPs as anticancer agents has been explored, there is a limited body of research focusing on the crucial physicochemical conditions influencing bAuNP production. In this study, we aim to identify the optimal growth phase of Pseudomonas aeruginosa cultures that maximizes the redox potential and coordinates the formation of bAuNPs with increased efficiency. The investigation employs 2,6-dichlorophenolindophenol (DCIP) as a redox indicator. Simultaneously, we explore the impact of temperature, pH, and incubation duration on the biosynthesis of bAuNPs, with a specific emphasis on their potential application as antitumor agents. Characterization of the resulting bAuNPs is conducted using ATR-FT-IR, TEM, and UV-Vis spectroscopy. To gain insights into the anticancer potential of bAuNPs, an experimental model is employed, utilizing both non-neoplastic (HPEpiC) and neoplastic (PC3) epithelial cell lines. Notably, P. aeruginosa cultures at 9 h/OD600 = 1, combined with biosynthesis at pH 9.0 for 24 h at 58 °C, produce bAuNPs that exhibit smaller, more spherical, and less aggregated characteristics. Crucially, these nanoparticles demonstrate negligible effects on HPEpiC cells while significantly impacting PC3 cells, resulting in reduced viability, migration, and lower IL-6 levels. This research lays the groundwork for the development of more specialized, economical, and ecologically friendly treatment modalities.
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Antineoplásicos , Nanopartículas Metálicas , Neoplasias da Próstata , Humanos , Masculino , Antibacterianos/química , Ouro/química , Espectroscopia de Infravermelho com Transformada de Fourier , Nanopartículas Metálicas/uso terapêutico , Nanopartículas Metálicas/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Química Verde/métodos , Extratos Vegetais/químicaRESUMO
La inversión uterina es una patología de presentación rara e infrecuente. Se presenta el caso de una paciente con inversión uterina no puerperal con requerimiento de histerectomía abdominal total. Sin antecedentes de importancia asistió al servicio de urgencias por un cuadro clínico de dolor abdominal de 10 días de evolución asociado a sangrado vaginal abundante con inestabilidad hemodinámica y sensación de masa vaginal. Al examen físico se evidenció una masa sobresaliente del canal vaginal de aspecto necrótico, por lo que se sospechó mioma nascens. Durante la estancia hospitalaria presentó inestabilidad hemodinámica, por lo que fue llevada a histerectomía abdominal de urgencia con hallazgo de inversión uterina. La inversión uterina no puerperal es infrecuente. Es importante realizar un buen diagnóstico clínico apoyado de las imágenes si se encuentran disponibles, la intervención quirúrgica es necesaria y proporciona un buen pronóstico. La histerectomía vaginal no es sencilla en estos casos, por lo que se recomienda la histerectomía abdominal total.
Uterine inversion is a rare and infrequent disease. The case of a patient with a non-puerperal uterine inversion that had to be treated with a total abdominal hysterectomy is presented in this study. With no important history of disease, she attended the emergency department presenting abdominal pain in the last 10 days associated with vaginal bleeding and mass sensation. The physical examination revealed a protruding necrotic-like mass through the vagina, hence the suspicion of a myoma nascens. During her hospital ward stay, she presented hemodynamic instability, urgent abdominal hysterectomy had to be done which revealed uterine inversion. Non-puerperal uterine inversion is infrequent. Precise clinical diagnosis is important supported by diagnostic imaging if available. The surgical intervention is necessary, giving a good prognosis. Vaginal hysterectomy is not easy in this type of cases, therefore total abdominal hysterectomy is recommended.
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Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias Uterinas/diagnóstico , Inversão Uterina/diagnóstico , Leiomioma/diagnóstico , Neoplasias Uterinas/cirurgia , Inversão Uterina/cirurgia , Histerectomia/métodos , Leiomioma/cirurgia , Leiomioma/complicaçõesRESUMO
The increasing attention that carbon-based nanomaterials have attracted due to their distinctive properties makes them one of the most widely used nanomaterials for industrial purposes. However, their toxicity and environmental effects must be carefully studied, particularly regarding aquatic biota. The implications of these carbon-based nanomaterials on aquatic ecosystems, due to their potential entry or accidental release during manufacturing and treatment processes, need to be studied because their impacts upon living organisms are not fully understood. In this research work, the toxicity of oxidized multi-walled carbon nanotubes (Ox-MWCNTs) was measured using the freshwater bivalve (Corbicula fluminea) after exposure to different concentrations (0, 0.1, 0.2, and 0.5 mg·L-1 Ox-MWCNTs) for 14 days. The oxidized multi-walled carbon nanotubes were analyzed (pH, Raman microscopy, high-resolution electron microscopy, and dynamic light scattering), showing their properties and behavior (size, aggregation state, and structure) in water media. The antioxidant defenses in the organism's digestive gland and gills were evaluated through measuring oxidative stress enzymes (glutathione-S-transferase, catalase, and superoxide dismutase), lipid peroxidation, and total ubiquitin. The results showed a concentration-dependent response of antioxidant enzymes (CAT and GST) in both tissues (gills and digestive glands) for all exposure periods in bivalves exposed to the different concentrations of oxidized multi-walled carbon nanotubes. Lipid peroxidation (MDA content) showed a variable response with the increase in oxidized multi-walled carbon nanotubes in the gills after 7 and 14 exposure days. Overall, after 14 days, there was an increase in total Ub compared to controls. Overall, the oxidative stress observed after the exposure of Corbicula fluminea to oxidized multi-walled carbon nanotubes indicates that the discharge of these nanomaterials into aquatic ecosystems can affect the biota as well as potentially accumulate in the trophic chain, and may even put human health at risk if they ingest contaminated animals.
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Corbicula , Nanotubos de Carbono , Poluentes Químicos da Água , Animais , Humanos , Corbicula/metabolismo , Antioxidantes/metabolismo , Nanotubos de Carbono/toxicidade , Ecossistema , Estresse Oxidativo , Glutationa Transferase/metabolismo , Água Doce , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análiseRESUMO
Photocatalysis stands as a very promising alternative to photovoltaics in exploiting solar energy and storing it in chemical products through a single-step process. A central obstacle to its broad implementation is its low conversion efficiency, motivating research in different fields to bring about a breakthrough in this technology. Using plasmonic materials to photosensitize traditional semiconductor photocatalysts is a popular strategy whose full potential is yet to be fully exploited. In this work, we use CdS quantum dots as a bridge system, reaping energy from Au nanostructures and delivering it to TiO2 nanoparticles serving as catalytic centers. The quantum dots can do this by becoming an intermediate step in a charge-transfer cascade initiated in the plasmonic system or by creating an electron-hole pair at an improved rate due to their interaction with the enhanced near-field created by the plasmonic nanoparticles. Our results show a significant acceleration in the reaction upon combining these elements in hybrid colloidal photocatalysts that promote the role of the near-field enhancement effect, and we show how to engineer complexes exploiting this approach. In doing so, we also explore the complex interplay between the different mechanisms involved in the photocatalytic process, highlighting the importance of the Au nanoparticles' morphology in their photosensitizing capabilities.
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Photocatalysis reactions are of great interest as an effective tool against the profusely increasing population of antibiotic-resistant bacteria species. In particular, the promising evidence on plasmon-sensitized titanium dioxide (TiO2) photocatalysis inspired us to investigate their antibacterial activity stemming from the photogenerated reactive oxygen species (ROS). Herein, TiO2 nanostructures were grown in situ within a silica (SiO2) aerogel matrix with high surface area and porosity, and their ROS-related phototoxic effects against Escherichia coli bacteria were investigated under solar- and visible-light irradiations. Photodegradation profiles obtained from Rhodamine B (RhB) organic dye used as a chemical probe proved that the types of ROS produced by SiO2/TiO2 aerogels varied depending on the electromagnetic spectrum portion that was used during material irradiation. Further, the SiO2/TiO2 aerogel matrix was decorated with silver-gold nanostars (Ag@Au NSs) to enhance its photocatalytic efficiency under visible light irradiations. Our design showed that plasmon-enriched composite aerogels efficiently boosted ROS production under visible light exposures and that the structures containing Ag@Au NSs showed a much more effective antibacterial effect compared to their counterparts.
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(1) Background: COVID-19 has evolved during seven epidemic waves in Spain. Our objective was to describe changes in mortality and severity in our hospitalized patients. (2) Method: This study employed a descriptive, retrospective approach for COVID-19 patients admitted to the Hospital de Fuenlabrada (Madrid, Spain) until 31 December 2022. (3) Results: A total of 5510 admissions for COVID-19 were recorded. The first wave accounted for 1823 (33%) admissions and exhibited the highest proportion of severe patients: 65% with bilateral pneumonia and 83% with oxygen saturation under 94% during admission and elevated levels of CRP, IL-6, and D-dimer. In contrast, the seventh wave had the highest median age (79 years) and comorbidity (Charlson: 2.7), while only 3% of patients had bilateral pneumonia and 3% required intubation. The overall mortality rate was 10.3%. The first wave represented 39% of the total. The variables related to mortality were age (OR: 1.08, 1.07-1.09), cancer (OR: 1.99, 1.53-2.60), dementia (OR: 1.82, 1.20-2.75), the Charlson index (1.38, 1.31-1.47), the need for high-flow oxygen (OR: 6.10, 4.94-7.52), mechanical ventilation (OR: 11.554, 6.996-19.080), and CRP (OR: 1.04, 1.03-1.06). (4) Conclusions: The variables associated with mortality included age, comorbidity, respiratory failure, and inflammation. Differences in the baseline characteristics of admitted patients explained the differences in mortality in each wave. Differences observed between patients admitted in the latest wave and the earlier ones suggest that COVID-19 has evolved into a distinct disease, requiring a distinct approach.
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COVID-19 , Epidemias , Humanos , Idoso , COVID-19/epidemiologia , Estudos Retrospectivos , Hospitais , HospitalizaçãoRESUMO
In this study, multicore-like iron oxide (Fe3O4) and manganese ferrite (MnFe2O4) nanoparticles were synthesized and combined with nanogels based on chitosan and alginate to obtain a multimodal drug delivery system. The nanoparticles exhibited crystalline structures and displayed sizes of 20 ± 3 nm (Fe3O4) and 11 ± 2 nm (MnFe2O4). The Fe3O4 nanoparticles showed a higher saturation magnetization and heating efficiency compared with the MnFe2O4 nanoparticles. Functionalization with citrate and bovine serum albumin was found to improve the stability and modified surface properties. The nanoparticles were encapsulated in nanogels, and provided high drug encapsulation efficiencies (~70%) using doxorubicin as a model drug. The nanogels exhibited sustained drug release, with enhanced release under near-infrared (NIR) laser irradiation and acidic pH. The nanogels containing BSA-functionalized nanoparticles displayed improved sustained drug release at physiological pH, and the release kinetics followed a diffusion-controlled mechanism. These results demonstrate the potential of synthesized nanoparticles and nanogels for controlled drug delivery, offering opportunities for targeted and on-demand release in biomedical applications.
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Hydroxyapatite (HA), the most common bioceramic material, offers attractive properties as a catalyst support. Highly crystalline mono-dispersed silver doped hydroxyapatite (Ag-HA) nanorods of 60 nm length was developed via hydrothermal processing. Silver dopant offered enhanced chemisorption for crystal violet (CV) contaminant. Silver was found to intensify negative charge on the catalyst surface; in this regard enhanced chemisorption of positively charged contaminants was accomplished. Silver dopant experienced decrease in the binding energy of valence electron for oxygen, calcium, and phosphorous using X-ray photoelectron spectroscopy XPS/ESCA; this finding could promote electron-hole generation and light absorption. Removal efficiency of Ag-HA nanocomposite for CV reached 88% after the synergistic effect with 1.0 mM H2O2; silver dopant could initiate H2O2 cleavage and intensify the release of active ȮH radicals. Whereas HA suffers from lack of microbial resistance; Ag-HA nanocomposite demonstrated high activity against Gram-positive (S. aureus) bacteria with zone of inhibition (ZOI) mm value of 18.0 mm, and high biofilm inhibition of 91.1%. Ag-HA nanocompsite experienced distinctive characerisitcs for utilization as green bioceramic photocatalyst for wastewater treatment.
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Peróxido de Hidrogênio , Purificação da Água , Prata/farmacologia , Staphylococcus aureus , Antibacterianos/farmacologia , Durapatita , Violeta GencianaRESUMO
The in vivo intramolecular recombination of a parental plasmid allows excising prokaryotic backbone from the eukaryotic cassette of interest, leading to the formation of, respectively, a miniplasmid and a minicircle. Here we describe a real-time PCR protocol suitable for the determination of recombination efficiency of parental plasmids with multimer resolution sites (MRS). The protocol was successfully applied to purified DNA samples obtained from E. coli cultures, allowing a more reproducible determination of recombination efficiency than densitometry analysis of agarose gels.