To overcome infection, hosts employ two defense strategies: resistance (which limits pathogen fitness), and tolerance (which reduces infection damage). These strategies may be influenced by environmental challenges such as food shortage, social conflict, and co-infections. Here, our objective was to assess defense strategies in rats infected with Trichinella spiralis and/or Trypanosoma cruzi under environmental challenges.
View Article and Find Full Text PDFis a Gram-negative bacillus responsible for a wide variety of potentially fatal infections and, in turn, constitutes a critical agent of healthcare-associated infections. Moreover, is characterized by multi-drug-resistant (MDR) bacteria, such as extended-spectrum beta-lactamases (ESBL) and carbapenemase (KPC) producer strains, representing a significant health problem. Because resistances make it difficult to eradicate using antibiotics, antimicrobial photodynamic therapy (aPDT) promises to be a favorable approach to complementing conventional therapy against MDR bacteria.
View Article and Find Full Text PDFspp. are Gram-positive bacteria that cause mild to severe infections, many associated with the oral cavity, such as periapical infections and healthcare-associated infections (HAIs). Many of these infections become serious diseases that are difficult to resolve, specifically when multidrug-resistant (MDR) strains cause them.
View Article and Find Full Text PDFWe studied the depuration mechanisms of metals (Cd, Cu, Pb, Zn, Mn, Ni, Cr, Fe) in Neohelice granulata, from sites with different human impacts (PC, a more impacted site and VM, a less impacted one). Our objectives included assessing metal concentrations (essential and non-essential) before and after depuration treatment, evaluating biochemical biomarkers (non-enzymatic and enzymatic) pre and post-treatment, and determining the role of metal-rich granules (MRG) in depuration. We observed variability in metals and biomarkers post-depuration, with no significant differences observed in PC, while Cd and Mn increased and Ni, Cu, and Fe decreased in VM.
View Article and Find Full Text PDFPhotodiagnosis Photodyn Ther
December 2023
Background: Pseudomonas aeruginosa is a Gram-negative bacillus that causes superficial and deep infections, which can be minor to life-threatening. Recently, P. aeruginosa has gained significant relevance due to the increased incidence of multidrug-resistant (MDR) strains that complicate antibiotic treatment.
View Article and Find Full Text PDFPhotodiagnosis Photodyn Ther
September 2023
Background: Acinetobacter baumannii is a Gram-negative, non-fermenting coccobacillus of the Moraxellaceae family. It is an opportunistic pathogen responsible for several hospital-acquired infections (HAIs) associated with skin and tissue infections at surgical sites, catheter-associated urinary tract infections, and central line catheters. Multidrug-resistant (MDR) A.
View Article and Find Full Text PDFMultidrug-resistant bacteria, such as ESBL producing-Klebsiella pneumoniae, have increased substantially, encouraging the development of complementary therapies such as photodynamic inactivation (PDI). PDI uses photosensitizer (PS) compounds that kill bacteria using light to produce reactive oxygen species. We test Ru-based PS to inhibit K.
View Article and Find Full Text PDFThe SARS-CoV-2 Omicron variant has increased infectivity and immune escape compared with previous variants, and caused the surge of massive COVID-19 waves globally. Despite a vast majority (~90%) of the population of Santa Fe city, Argentina had been vaccinated and/or had been infected by SARS-CoV-2 when Omicron emerged, the epidemic wave that followed its arrival was by far the largest one experienced in the city. A serosurvey conducted prior to the arrival of Omicron allowed to assess the acquired humoral defences preceding the wave and to conduct a longitudinal study to provide individual-level real-world data linking antibody levels and protection against COVID-19 during the wave.
View Article and Find Full Text PDFBackground: Extended-spectrum beta-lactamase (ESBL) and carbapenemase (KPC) producing are multidrug-resistant bacteria (MDR) with the highest risk to human health. The significant reduction of new antibiotics development can be overcome by complementing with alternative therapies, such as antimicrobial photodynamic therapy (aPDI). Through photosensitizer (PS) compounds, aPDI produces local oxidative stress-activated by light (photooxidative stress), nonspecifically killing bacteria.
View Article and Find Full Text PDFBackground: The extended-spectrum beta-lactamase (ESBL) is one of the leading causes of health-associated infections (HAIs), whose antibiotic treatments have been severely reduced. Moreover, HAI bacteria may harbor pathogenic factors such as siderophores, enzymes, or capsules, which increase the virulence of these strains. Thus, new therapies, such as antimicrobial photodynamic inactivation (aPDI), are needed.
View Article and Find Full Text PDFPhotodiagnosis Photodyn Ther
June 2021
Background: Staphylococcus aureus is a Gram-positive spherical bacterium that commonly causes various infections which can range from superficial to life-threatening. Hospital strains of S. aureus are often resistant to antibiotics, which has made their treatment difficult in recent decades.
View Article and Find Full Text PDFBackground: Due to increased bacterial multi-drug resistance (MDR), there is an antibiotic depletion to treat infectious diseases. Consequently, other promising options have emerged, such as the antimicrobial photodynamic inactivation therapy (aPDI) based on photosensitizer (PS) compounds to produce light-activated local oxidative stress (photooxidative stress). However, there are scarce studies regarding the mode of action of PS compounds to induce photooxidative stress on pathogenic γ-proteobacteria such as MDR-Klebsiella pneumoniae.
View Article and Find Full Text PDFPhotodiagnosis Photodyn Ther
September 2020
Background: Carbapenemase-producing strains of Klebsiella pneumoniae (KPC) are one of the multi-drug resistant bacteria with the highest risk for human health. The colistin is the only antibiotic option against KPC; however, due to its emerging resistance, therapies such as antimicrobial photodynamic inactivation (aPDI), are needed. APDI uses photosensitizer compounds (PS) to produce light-activated local oxidative stress (photooxidative stress).
View Article and Find Full Text PDFSurvivin (BIRC5) is an anti-apoptotic protein that is important in cancer. Mechanisms responsible for controlling Survivin levels in cells include transcriptional regulation and modulation of protein stability via post-translational modifications; however to date, translational control has been poorly studied. Here, we focused particularly on the primary control elements present in the Survivin 5' untranslated region (5'UTR).
View Article and Find Full Text PDFBackground: Bacteria prevalent in the hospital environment have developed multi-drug resistance (MDR), such as the carbapenemase-producing Klebsiella pneumoniae (KPC). Photodynamic therapy (PDT), which uses light-activated photosensitizer compounds (PSs), has emerged as an alternative to antibiotics. Cationic-PSs have a better bactericidal effect by interacting more closely with the bacterial envelope.
View Article and Find Full Text PDFBackground: Coinfections of HIV patients with hepatitis B virus (HBV) and hepatitis C virus (HCV) are mayor public health problems, contributing to the emerging burden of HIV-associated hepatic mortality. Coinfection rates vary geographically, depending on various factors such as predominant transmission modes, HBV vaccination rates, and prevalence of HBV and HCV in the general population. In South America, the epidemiology of coinfections is uncertain, since systematic studies are scarce.
View Article and Find Full Text PDFThe emergence of multi-drug resistance for pathogenic bacteria is one of the most pressing global threats to human health in the 21st century. Hence, the availability of new treatment becomes indispensable to prevent morbidity and mortality caused by infectious agents. This article reviews the antimicrobial properties of photodynamic therapy (PDT), which is based on the use of photosensitizers compounds (PSs).
View Article and Find Full Text PDFThe Human Respiratory Syncytial Virus (hRSV) and the Human Metapneumovirus (hMPV) are two pneumoviruses that are leading agents causing acute lower respiratory tract infections (ALRTIs) affecting young infants, the elderly, and immunocompromised patients worldwide. Since these pathogens were first discovered, many approaches for the licensing of safe and effective vaccines have been explored being unsuccessful to date. We have previously described that immunization with recombinant strains of Bacillus Calmette-Guérin (rBCG) expressing the hRSV nucleoprotein (rBCG-N) or the hMPV phosphoprotein (rBCG-P) induced immune protection against each respective virus.
View Article and Find Full Text PDFHuman Respiratory Syncytial Virus (hRSV), human Metapneumovirus (hMPV) and Adenovirus (ADV), are three of the most prevalent viruses responsible for pneumonia and bronchiolitis in children and elderly worldwide, accounting for a high number of hospitalizations annually. Diagnosis of these viruses is required to take clinical actions that allow an appropriate patient management. Thereby, new strategies to design fast diagnostic methods are highly required.
View Article and Find Full Text PDFGlobally, as a leading agent of acute respiratory tract infections in children <5 years of age and the elderly, the human metapneumovirus (HMPV) has gained considerable attention. As inferred from studies comparing vaccinated and experimentally infected mice, the acquired immune response elicited by this pathogen fails to efficiently clear the virus from the airways, which leads to an exaggerated inflammatory response and lung damage. Furthermore, after disease resolution, there is a poor development of T and B cell immunological memory, which is believed to promote reinfections and viral spread in the community.
View Article and Find Full Text PDFAcute respiratory tract infections (ARTIs) are the major cause of child mortality worldwide. The human metapneumovirus (hMPV) is one of the leading causes of child hospitalizations due to pneumonia. The adaptive immune response generated by the host against hMPV is usually inefficient at protecting from reinfections, which is repeat throughout life, from childhood to old age.
View Article and Find Full Text PDFRespiratory Syncytial Virus (RSV) is the first cause of hospitalization due to bronchiolitis in infants. RSV bronchiolitis has been linked to asthma and recurrent wheezing, however the mechanisms behind this association have not been elucidated. Here, we evaluated the cytokine and chemokine profiles in the airways in infants with RSV bronchiolitis.
View Article and Find Full Text PDFHuman metapneumovirus (hMPV) is a leading cause of acute respiratory tract infections in children and the elderly. The mechanism by which this virus triggers an inflammatory response still remains unknown. Here, we evaluated whether the thymic stromal lymphopoietin (TSLP) pathway contributes to lung inflammation upon hMPV infection.
View Article and Find Full Text PDFHuman respiratory syncytial virus (hRSV) is the leading cause of bronchiolitis and pneumonia in young children worldwide. The recurrent hRSV outbreaks and reinfections are the cause of a significant public health burden and associate with an inefficient antiviral immunity, even after disease resolution. Although several mouse- and human cell-based studies have shown that hRSV infection prevents naïve T-cell activation by antigen-presenting cells, the mechanism underlying such inhibition remains unknown.
View Article and Find Full Text PDFAlong with the human respiratory syncytial virus (hRSV), the human metapneumovirus (hMPV) is one of the leading causes of childhood hospitalization and a major health burden worldwide. Unfortunately, owing to an inefficient immunological memory, hMPV infection provides limited immune protection against reinfection. Furthermore, hMPV can induce an inadequate Th2 type immune response that causes severe lung inflammation, leading to airway obstruction.
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