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Actinomycosis is a rare infectious disease characterized by slowly progressive, chronic suppurative lesions, often mistaken for malignancies due to its ability to mimic them. It is caused by Actinomyces bacteria, which are part of the normal flora of the human oropharynx, gastrointestinal, and urogenital tracts. This case report describes a 51-year-old male with a history of mandibular rhabdomyosarcoma presenting with severe shoulder and hip pain, dysphagia, and headaches, initially suspected to be a cancer recurrence. However, after further investigation, including a PET-CT and tonsillectomy, the diagnosis of actinomycosis was confirmed through histopathological examination. The case highlights the diagnostic challenges of actinomycosis, especially in patients with complex clinical histories, emphasizing the importance of considering it as a differential diagnosis in similar presentations. The patient was treated with long-term antibiotic therapy, predominantly beta-lactams, demonstrating the necessity of a comprehensive diagnostic approach and the implications of a delayed diagnosis. This case underscores the critical need for high clinical suspicion and awareness among healthcare professionals regarding the potential for actinomycosis to mimic more common diseases, ensuring timely and accurate treatment.
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Actinomicose , Rabdomiossarcoma , Humanos , Masculino , Pessoa de Meia-Idade , Actinomicose/diagnóstico , Actinomicose/tratamento farmacológico , Diagnóstico Diferencial , Rabdomiossarcoma/diagnóstico , Antibacterianos/uso terapêutico , Tonsila Palatina/microbiologiaRESUMO
The growing challenge of chronic wounds and antibiotic resistance has spotlighted the potential of dual-function peptides (antimicrobial and wound healing) as novel therapeutic strategies. The investigation aimed to characterize and correlate in silico the physicochemical attributes of these peptides with their biological activity. We sourced a dataset of 207 such peptides from various peptide databases, followed by a detailed analysis of their physicochemical properties using bioinformatic tools. Utilizing statistical tools like clustering, correlation, and principal component analysis (PCA), patterns and relationships were discerned among these properties. Furthermore, we analyzed the peptides' functional domains for insights into their potential mechanisms of action. Our findings spotlight peptides in Cluster 2 as efficacious in wound healing, whereas Cluster 1 peptides exhibited pronounced antimicrobial potential. In our study, we identified specific amino acid patterns and peptide families associated with their biological activities, such as the cecropin antimicrobial domain. Additionally, we found the presence of polar amino acids like arginine, cysteine, and lysine, as well as apolar amino acids like glycine, isoleucine, and leucine. These characteristics are crucial for interactions with bacterial membranes and receptors involved in migration, proliferation, angiogenesis, and immunomodulation. While this study provides a groundwork for therapeutic development, translating these findings into practical applications necessitates additional experimental and clinical research.
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Anti-Infecciosos , Antifibrinolíticos , Humanos , Anti-Infecciosos/farmacologia , Cicatrização , Aminoácidos , ArgininaRESUMO
The COVID-19 pandemic has had significant impacts on healthcare systems around the world, including in Latin America. In Colombia, there have been over 23,000 confirmed cases and 100 deaths since 2022, with the highest number of cases occurring in females and the highest number of deaths in males. The elderly and those with comorbidities, such as arterial hypertension, diabetes mellitus, and respiratory diseases, have been particularly affected. Coinfections with other microorganisms, including dengue virus, Klebsiella pneumoniae, and Mycobacterium tuberculosis, have also been a significant factor in increasing morbidity and mortality rates in COVID-19 patients. It is important for surveillance systems to be improved and protocols to be established for the early detection and management of coinfections in COVID-19. In addition to traditional treatments, alternatives such as zinc supplementation and nanomedicine may have potential in the fight against COVID-19. It is also crucial to consider the social, labor, educational, psychological, and emotional costs of the pandemic and to address issues such as poverty and limited access to potable water in order to better prepare for future pandemics.
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COVID-19 , Coinfecção , Superinfecção , Masculino , Feminino , Humanos , Idoso , COVID-19/epidemiologia , SARS-CoV-2 , Pandemias , Colômbia/epidemiologia , Coinfecção/epidemiologia , Superinfecção/epidemiologiaRESUMO
Mesenteric ischemia is a serious complication that can occur after splenectomy for hemolytic anemia, potentially leading to lifelong intestinal problems such as ischemia and/or portal hypertension. We present the case of a 33-year-old man with a history of autoimmune hemolytic anemia and splenectomy who developed mesenteric ischemia. The patient experienced abdominal pain and diarrhea, and imaging studies revealed mesenteric vein thrombosis. Surgical intervention confirmed the diagnosis. This case significantly contributes to the existing literature by providing insights into the occurrence of mesenteric ischemia in younger individuals with predisposing factors, as well as its clinical presentation, diagnostic challenges, and severity. Moreover, it has implications for the future diagnosis and management of long-term mesenteric ischemia in patients who have undergone splenectomy for hemolytic anemia.
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Anemia Hemolítica , Hipertensão Portal , Isquemia Mesentérica , Masculino , Humanos , Adulto , Isquemia Mesentérica/etiologia , Isquemia Mesentérica/diagnóstico , Veia Porta , Hipertensão Portal/complicações , Isquemia/etiologia , Anemia Hemolítica/complicaçõesRESUMO
A serious pandemic has been caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The interaction between spike surface viral protein (Sgp) and the angiotensin-converting enzyme 2 (ACE2) cellular receptor is essential to understand the SARS-CoV-2 infectivity and pathogenicity. Currently, no drugs are available to treat the infection caused by this coronavirus and the use of antimicrobial peptides (AMPs) may be a promising alternative therapeutic strategy to control SARS-CoV-2. In this study, we investigated the in silico interaction of AMPs with viral structural proteins and host cell receptors. We screened the antimicrobial peptide database (APD3) and selected 15 peptides based on their physicochemical and antiviral properties. The interactions of AMPs with Sgp and ACE2 were performed by docking analysis. The results revealed that two amphibian AMPs, caerin 1.6 and caerin 1.10, had the highest affinity for Sgp proteins while interaction with the ACE2 receptor was reduced. The effective AMPs interacted particularly with Arg995 located in the S2 subunits of Sgp, which is key subunit that plays an essential role in viral fusion and entry into the host cell through ACE2. Given these computational findings, new potentially effective AMPs with antiviral properties for SARS-CoV-2 were identified, but they need experimental validation for their therapeutic effectiveness.
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Enzima de Conversão de Angiotensina 2/química , Tratamento Farmacológico da COVID-19 , SARS-CoV-2/química , Glicoproteína da Espícula de Coronavírus/química , Proteínas de Anfíbios/química , Proteínas de Anfíbios/uso terapêutico , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Antivirais/química , Antivirais/uso terapêutico , Sítios de Ligação/genética , COVID-19/genética , COVID-19/virologia , Simulação por Computador , Humanos , Pandemias , Proteínas Citotóxicas Formadoras de Poros/química , Proteínas Citotóxicas Formadoras de Poros/uso terapêutico , Ligação Proteica/genética , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/uso terapêutico , Proteínas Estruturais Virais/química , Proteínas Estruturais Virais/genética , Proteínas Estruturais Virais/uso terapêuticoRESUMO
Peptides are naturally produced by all organisms and exhibit a wide range of physiological, immunomodulatory, and wound healing functions. Furthermore, they can provide with protection against microorganisms and tumor cells. Their multifaceted performance, high selectivity, and reduced toxicity have positioned them as effective therapeutic agents, representing a positive economic impact for pharmaceutical companies. Currently, efforts have been made to invest in the development of new peptides with antimicrobial and anticancer properties, but the poor stability of these molecules in physiological environments has triggered a bottleneck. Therefore, some tools, such as nanotechnology and in silico approaches can be applied as alternatives to try to overcome these obstacles. In silico studies provide a priori knowledge that can lead to the development of new anticancer peptides with enhanced biological activity and improved stability. This review focuses on the current status of research in peptides with dual antimicrobial-anticancer activity, including advances in computational biology using in silico analyses as a powerful tool for the study and rational design of these types of peptides.
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Anti-Infecciosos/química , Peptídeos Catiônicos Antimicrobianos/química , Antineoplásicos/química , Desenho de Fármacos , Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Biologia Computacional , HumanosRESUMO
In this study, a systematic review of randomized clinical trials conducted from January 2000 to December 2023 was performed to examine the efficacy of psychobiotics-probiotics beneficial to mental health via the gut-brain axis-in adults with psychiatric and cognitive disorders. Out of the 51 studies involving 3353 patients where half received psychobiotics, there was a notably high measurement of effectiveness specifically in the treatment of depression symptoms. Most participants were older and female, with treatments commonly utilizing strains of Lactobacillus and Bifidobacteria over periods ranging from 4 to 24 weeks. Although there was a general agreement on the effectiveness of psychobiotics, the variability in treatment approaches and clinical presentations limits the comparability and generalization of the findings. This underscores the need for more personalized treatment optimization and a deeper investigation into the mechanisms through which psychobiotics act. The research corroborates the therapeutic potential of psychobiotics and represents progress in the management of psychiatric and cognitive disorders.
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Transtornos Mentais , Probióticos , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Probióticos/uso terapêutico , Feminino , Transtornos Mentais/tratamento farmacológico , Transtornos Mentais/terapia , Transtornos Cognitivos/tratamento farmacológico , Masculino , Resultado do Tratamento , Adulto , Eixo Encéfalo-Intestino/efeitos dos fármacos , Pessoa de Meia-Idade , Microbioma Gastrointestinal/efeitos dos fármacos , Lactobacillus , Idoso , BifidobacteriumRESUMO
Cutaneous leishmaniasis (CL) is a zoonotic disease caused by protozoa of the Leishmania genus, transmitted by vectors from the Phlebotominae subfamily. The interaction between the vector, reservoir, and parasite is susceptible to climate change. This study explores how temperature and rainfall influenced the incidence of CL in 15 Colombian municipalities between 2017 and 2019. Epidemiological data were obtained from Colombia's Instituto Nacional de Salud, while climatological data came from the Instituto de Hidrología, Meteorología y Estudios Ambientales. Using Spearman's rank correlation coefficient, we examined the relationships between monthly climatic variables and the cumulative incidence of CL, considering various lag times. The data were further analyzed using Locally Weighted Scatterplot Smoothing (LOWESS). Our findings reveal both significant positive and negative correlations, depending on locality and climate variables. LOWESS analysis indicates that while rainfall-related incidence remains stable, temperature impacts incidence in a parabolic trend. This study underscores the significant yet complex influence of climatic factors on CL incidence. The insights gained could aid public health efforts by improving predictive models and crafting targeted interventions to mitigate the disease's impact, particularly in regions vulnerable to climate variability.
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Non-small-cell lung cancer (NSCLC) comprises approximately 85% of all lung cancer cases, often diagnosed at advanced stages, which diminishes the effective treatment options and survival rates. This systematic review assesses the utility of emerging biomarkers-circulating tumor DNA (ctDNA), microRNAs (miRNAs), and the blood tumor mutational burden (bTMB)-enhanced by next-generation sequencing (NGS) to improve the diagnostic accuracy, prognostic evaluation, and treatment strategies in NSCLC. Analyzing data from 37 studies involving 10,332 patients from 2020 to 2024, the review highlights how biomarkers like ctDNA and PD-L1 expression critically inform the selection of personalized therapies, particularly beneficial in the advanced stages of NSCLC. These biomarkers are critical for prognostic assessments and in dynamically adapting treatment plans, where high PD-L1 expression and specific genetic mutations (e.g., ALK fusions, EGFR mutations) significantly guide the use of targeted therapies and immunotherapies. The findings recommend integrating these biomarkers into standardized clinical pathways to maximize their potential in enhancing the treatment precision, ultimately fostering significant advancements in oncology and improving patient outcomes and quality of life. This review substantiates the prognostic and predictive value of these biomarkers and emphasizes the need for ongoing innovation in biomarker research.
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The prevalence of schizophrenia, affecting approximately 1% of the global population, underscores the urgency for innovative therapeutic strategies. Recent insights into the role of neuroinflammation, the gut-brain axis, and the microbiota in schizophrenia pathogenesis have paved the way for the exploration of psychobiotics as a novel treatment avenue. These interventions, targeting the gut microbiome, offer a promising approach to ameliorating psychiatric symptoms. Furthermore, advancements in artificial intelligence and nanotechnology are set to revolutionize psychobiotic development and application, promising to enhance their production, precision, and effectiveness. This interdisciplinary approach heralds a new era in schizophrenia management, potentially transforming patient outcomes and offering a beacon of hope for those afflicted by this complex disorder.
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INTRODUCTION: This academic article discusses the historical underrepresentation of female in science, with a focus on Latin America. It highlights the importance of both technical and non-technical skills in the medical-surgical field, particularly the role of research skills. The study aims to quantify and characterize the scientific output of Latin American female researchers over the past decade, providing insights into the challenges and opportunities in low and middle-income countries. MATERIAL AND METHODS: A retrospective cross-sectional bibliometric study was conducted in 2023, focusing on pediatric surgical science journals in Scopus and PubMed. It assessed Latin American female participation, journal details, and interaction networks, using SPSS and Gephi software. The period analyzed was from January 2012 to December 2022. RESULTS: Between 2012 and 2022, 727 articles with Latin authorship in pediatric surgery were analyzed across 304 journals. Of these, 63.69% had female co-authors. The majority were original articles (53.13%), with contributions from Brazil, Mexico, and Chile. Notable journals included the Journal of Pediatric Surgery and Child's Nervous System. Keywords like Laparoscopy and Cardiac surgery were common. A growth trend in female Latin American publications was observed, despite temporary declines. CONCLUSIONS: This study highlights a growing trend in Latin American females' scientific contributions to pediatric surgery from 2012 to 2022, although a gender gap persists. The research mainly consists of primary data studies, with a focus on Brazil and Mexico from public institutions. The Journal of Pediatric Surgery featured prominently, and common topics included Laparoscopy, Cardiac surgery, Liver transplant, Congenital heart defects, and COVID-19. LEVEL OF EVIDENCE: IV.
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Bibliometria , Pediatria , Especialidades Cirúrgicas , América Latina , Humanos , Feminino , Estudos Transversais , Estudos Retrospectivos , Pediatria/estatística & dados numéricos , Especialidades Cirúrgicas/estatística & dados numéricos , Médicas/estatística & dados numéricos , Autoria , Publicações Periódicas como Assunto/estatística & dados numéricos , Pesquisa Biomédica/estatística & dados numéricosRESUMO
Postpartum depression (PPD) affects 10-20% of women. Traditional treatments have raised concerns, but omega-3 fatty acids show potential as an alternative. This thematic review, sourced from databases like PubMed and Scopus between 1 February 2023 and 15 March 2023, seeks to delve into the various perspectives on omega-3 supplementation for PPD. The criteria included studies detailing depressive symptoms, social functioning, and neurobiological variables. The review includes research with women showing PPD symptoms, randomized clinical trials, and articles in Spanish, English, and French. Exclusions were studies lacking proper control comparisons and other interventions besides omega-3. Data extraction was performed independently. Two key studies provide contrasting findings on omega-3's impact on PPD symptoms. In the study comparing DHA supplementation to a placebo, significant differences were not found in the EPDS scale, but differences were observed in the BDI scale. In contrast, another study recorded a significant decrease in depression scores in all dose groups, with reductions of 51.5% in the EPDS scale and 48.8% in the HRSD scale. Other studies, encompassing both prenatal and postpartum periods, underscore the differentiation between prenatal depression and PPD. Despite shared diagnostic criteria, PPD presents unique symptoms like restlessness, emotional lability, and baby-related concerns. It is crucial to address biases and obtain specific results, recommending exclusive PPD-focused studies. This review emphasizes the need for continuous exploration of omega-3's relationship with PPD to enhance the life quality of pregnant women and their families.
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Non-small cell lung cancer (NSCLC) is a significant public health concern with high mortality rates. Recent advancements in genomic data, bioinformatics tools, and the utilization of biomarkers have improved the possibilities for early diagnosis, effective treatment, and follow-up in NSCLC. Biomarkers play a crucial role in precision medicine by providing measurable indicators of disease characteristics, enabling tailored treatment strategies. The integration of big data and artificial intelligence (AI) further enhances the potential for personalized medicine through advanced biomarker analysis. However, challenges remain in the impact of new biomarkers on mortality and treatment efficacy due to limited evidence. Data analysis, interpretation, and the adoption of precision medicine approaches in clinical practice pose additional challenges and emphasize the integration of biomarkers with advanced technologies such as genomic data analysis and artificial intelligence (AI), which enhance the potential of precision medicine in NSCLC. Despite these obstacles, the integration of biomarkers into precision medicine has shown promising results in NSCLC, improving patient outcomes and enabling targeted therapies. Continued research and advancements in biomarker discovery, utilization, and evidence generation are necessary to overcome these challenges and further enhance the efficacy of precision medicine. Addressing these obstacles will contribute to the continued improvement of patient outcomes in non-small cell lung cancer.
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Rectal cancer (RC) is one of the most common malignant neoplasms, and cancer stem cells (CSCs) of the intestinal tract have been implicated in its origin. The oncofetal protein OCT4 has been linked to neoplastic processes, but its role and clinical significance in RC are unknown. This study investigates the expression of the stem cell marker OCT4 related to clinical-pathological characteristics and its clinical significance in RC patients. The expression level of stem cell marker OCT4 was analyzed in 22 primary rectal tumors by western blot. The association between OCT4 protein expression and the clinical-pathological features of tumors was evaluated by χ2 test and Fisher's exact test. We demonstrated that the expression of the stem cell marker OCT4 was observed in tumor tissue but not adjacent non-tumor tissue. High expression of the stem cell marker OCT4 was significantly associated with histological differentiation grade (p = 0.039), tumor invasion level (p = 0.004), lymph node involvement (p = 0.044), tumor-node-metastasis (TNM) stage (p = 0.002), and clinical stage (p = 0.021). These findings suggest that high OCT4 expression is associated with a more aggressive RC phenotype, with a greater likelihood of progression and metastasis. These results shed light on the importance of targeting this CSC marker to attenuate RC progression.
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Vinasse, a waste from the bioethanol industry, presents a crucial environmental challenge due to its high organic matter content, which is difficult to biodegrade. Currently, no sustainable alternatives are available for treating the amount of vinasse generated. Conversely, biopolymers such as cellulose, carboxymethylcellulose, and chitosan are emerging as an interesting alternative for vinasse control due to their flocculating capacity against several organic compounds. This study seeks to determine the thermodynamic behavior of in silico interactions among three biopolymers (cellulose, carboxymethylcellulose, and chitosan) regarding 15 organic compounds found in vinasse. For this, the Particle Mesh Ewald (PME) method was used in association with the Verlet cutoff scheme, wherein the Gibbs free energy (ΔG) was calculated over a 50 ns simulation period. The findings revealed that cellulose showed a strong affinity for flavonoids like cyanidin, with a maximum free energy of -84 kJ/mol and a minimum of -55 kJ/mol observed with phenolic acids and other flavonoids. In contrast, chitosan displayed the highest interactions with phenolic acids, such as gallic acid, reaching -590 kJ/mol. However, with 3-methoxy-4-hydroxyphenyl glycol (MHPG), it reached an energy of -70 kJ/mol. The interaction energy for flavonoid ranged from -105 to -96 kJ/mol. Finally, carboxymethylcellulose (CMC) demonstrated an interaction energy with isoquercetin of -238 kJ/mol, while interactions with other flavonoids were almost negligible. Alternatively, CMC exhibited an interaction energy of -124 kJ/mol with MHPG, while it was less favorable with other phenolic acids with minimal interactions. These results suggest that there are favorable interactions for the interfacial sorption of vinasse contaminants onto biopolymers, indicating their potential for use in the removal of contaminants from the effluents of the bioethanol industry.
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Background: There is very limited evidence on biomarkers for evaluating the clinical behavior and therapeutic response in rectal cancer (RC) with positive expression of cancer stem cells (CSCs). Methods: An exploratory prospective study was conducted, which included fresh samples of tumor tissue from 109 patients diagnosed with primary RC. Sociodemographic, pathological and clinical characteristics were collected from medical records and survey. The OCT4 protein was isolated using the Western Blot technique. It was calculated the ΔCEA, ΔOCT4, and ΔOCT4/GUSB values by assessing the changes before and after chemotherapy, aiming to evaluate the therapeutic response. Results: Patients had an average age of 69.9 years, with 55% (n=60) being male. Approximately 63.3% of the tumors were undifferentiated, and the most frequent staging classification was pathological stage III (n=64; 58.7%). Initial positive expression was observed in 77.1% of the patients (n=84), and the median ΔCEA was -1.03 (-3.82 - 0.84) ng/ml, with elevated levels (< -0.94 ng/ml) found in 51.4% of the subjects (n=56). Being OCT4 positive and having an elevated ΔCEA value were significantly associated with undifferentiated tumor phenotype (p=0.002), advanced tumor progression stage (p <0.001), and negative values of ΔOCT4 (p <0.001) (suggestive of poor therapeutic response) compared to those without this status. Conclusion: This study identified a significant and directly proportional association among the values of ΔCEA, ΔOCT4, and ΔOCT4/GUSB. These findings suggest that ΔCEA holds potential as a clinical biomarker for determining the undifferentiated tumor phenotype, advanced clinical stage, and poor therapeutic response in RC with CSCs positive expression.
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The prevalence of fungal infections is increasing worldwide, especially that of aspergillosis, which previously only affected people with immunosuppression. Aspergillus fumigatus can cause allergic bronchopulmonary aspergillosis and endangers public health due to resistance to azole-type antimycotics such as fluconazole. Antifungal peptides are viable alternatives that combat infection by forming pores in membranes through electrostatic interactions with the phospholipids as well as cell death to peptides that inhibit protein synthesis and inhibit cell replication. Engineering antifungal peptides with nanotechnology can enhance the efficacy of these therapeutics at lower doses and reduce immune responses. This manuscript explains how antifungal peptides combat antifungal-resistant aspergillosis and also how rational peptide design with nanotechnology and artificial intelligence can engineer peptides to be a feasible antifungal alternative.
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Congenital knee dislocation (CKD) is a rare disease with an estimated incidence of 1 per 100,000 live births, characterized by a rare musculoskeletal malformation in genu recurvatum deformity present at birth, affecting one or both lower limbs. The diagnosis may be suspected during ultrasound when observing that the situation of the extremities is not correct, and is confirmed by physical examination at birth, with plain radiography being helpful to establish the degree of severity. At present there are controversies regarding treatment and there is no definitive protocol. We present a new case of CKD, observed in the city of Manizales, diagnosed immediately after birth.
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Bacterial antibiotic resistance is a serious global public health concern. Infections caused by colistin-resistant Pseudomonas aeruginosa (CRPa) strains represent a serious threat due to their considerable morbidity and mortality rates, since most of the current empirical antibiotic therapies are ineffective against these strains. Accordingly, cationic antimicrobial peptides (CAMPs) have emerged as promising alternatives to control resistant bacteria. In this study, the interaction of a CAMP derived from cecropin D-like (∆M2) with model membranes mimicking bacterial biomembranes of wild-type (WTPa) strains of P. aeruginosa and CRPa was evaluated through in vitro and in silico approaches. In vitro interaction was determined by infrared spectroscopy, whereas in silico molecular dynamics was performed to predict specific interactions between amino acids of ∆M2 and lipids of model membrane systems. Experimental analysis showed this peptide interacted with the lipids of bacterial-like model membranes of WTPa and CRPa. In both cases, an increase in the concentration of peptides induced an increase in the phase transition temperature of the lipid systems. On the other hand, the peptides in solution underwent a transition from a random to a helical secondary structure after interacting with the membranes mostly favored in the CRPa system. The α-helix structure percentage for ΔM2 interacting with WTPa and CRPa lipid systems was 6.4 and 33.2%, respectively. Finally, molecular dynamics showed ∆M2 to have the most affinities toward the phospholipids palmitoyl-oleyl-phosphatidylglycerol (POPG) and palmitoyl-oleoyl-phosphatidylethanolamine (POPE) that mimic membranes of WTPa and CRPa, respectively. This work provides clues for elucidating the membrane-associated mechanism of action of ∆M2 against colistin-susceptible and -resistant strains of Pseudomonas aeruginosa.
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Antimicrobial treatment alternatives for methicillin-resistant Staphylococcus aureus (MRSA) are increasingly limited. MRSA strains are resistant to methicillin due to the formation of ß-lactamase enzymes, as well as the acquisition of the mecA gene, which encodes the penicillin-binding protein (PBP2a) that reduces the affinity for ß-lactam drugs. Previous studies have shown that the use of ampicillin-loaded nanoparticles can improve antimicrobial activity on resistant S. aureus strains. However, the biological mechanism of this effect has not yet been properly elucidated. Therefore, this short communication focused on characterizing the in silico interactions of the PBP2a membrane receptor protein from S. aureus against the monomeric units of two polymeric materials previously used in the development of different nanoparticles loaded with ampicillin. Such polymers correspond to Eudragit E-100 chloride (EuCl) and the sodium salt of poly(maleic acid-alt-octadecene) (PAM-18Na). For this, molecular coupling studies were carried out in the active site of the PBP2a protein with the monomeric units of both polymers in neutral and ionized form, as well as with ampicillin antibiotic (model ß-lactam drug). The results showed that ampicillin, as well as the monomeric units of EuCl and PAM18Na, described a slight binding free energy to the PBPa2 protein. In addition, it was found that the amino acids of the active site of the PBPa2 protein have interactions of different types and intensities, suggesting, in turn, different forms of protein-substrate coupling.