Selection Of Agents Research Articles

P-1523. Evaluation of Standardized Treatment Regimens for Patients with Documented Melioidosis Septicemia at Tertiary Care Hospital in Thailand

Abstract Background Burkholderia pseudomallei (B. pseudomallei), an environmental Gram-negative bacterium, is the causative agent of melioidosis in humans. Therefore, its biothreat potential, the U.S. Centers for Disease Control and Prevention designates it as a tier 1 select agent. Melioidosis is predominantly a disease in subtropical and tropical regions. It is endemic in northern Australia and parts of Southeast Asia and the Indian subcontinent. Mostly, melioidosis (85%) results in acute infections from recent bacterial exposure. The majority of patients with acute melioidosis present with sepsis with or without pneumonia, or localized abscesses, regardless of the route of infection. Currently, therapy consists of an intensive phase of a minimum of 10 days with intravenous ceftazidime or a carbapenem (meropenem or imipenem), with or without trimethoprim-sulfamethoxazole to prevent mortality followed by an eradication phase with oral antibiotics to prevent relapse. In Thailand, still found the mortality rate was 40%.We have uncleared study clinical outcomes comparable to ceftazidime and carbapenems treatment in documented melioidosis septicemia. This is the first study to evaluate the efficacy of ceftazidime compared to carbapenems in patients with documented melioidosis septicemia whose blood cultures confirmed B. pseudomallei and susceptible to both ceftazidime and carbapenems in Thailand. Baseline characteristic (N=264) Methods A retrospective study was conducted at Sunprasitthiprasong hospital, Thailand from 2021-2023. Adult patients who were admitted had documented positive B. pseudomallei septicemia and received ceftazidime or carbapenem at least one dose. The exclusion criteria were incomplete chart summary. Significant level p-value≤0.05 (STATA version 16) ceftazidime versus carbapenems in non-septic shock patients p-value < 0.001 Results 264 patients were included and reported B. pseudomallei septicemia susceptibility to ceftazidime and meropenem were 264 (100%) pathogens and imipenem/cilastatin 262 (99.24%) pathogens. ceftazidime versus carbapenems in septic shock patients p-value =0.034 Conclusion Ceftazidime compared to carbapenems in the intensive phase for documented melioidosis septicemia trends higher survival rate in 14 days after confirming pathogens in non-severe patients. Furthermore, randomized controlled trials (RCTs) will prove clinical outcomes in documented melioidosis septicemia. Factors associated with mortality Disclosures All Authors: No reported disclosures

P-1106. Sulopenem is Efficacious in a Rabbit Model of Inhalational Anthrax

Abstract Background Sulopenem (SUL) is a penem β-lactam antibiotic in development for the treatment of resistant bacterial infections. It is available as intravenous and oral prodrug formulations, and its activity aligns with the most urgent drug-resistant antimicrobial threats defined by the CDC. SUL possesses potent activity against Enterobacterales species that encode ESBLs or AmpC-type β-lactamases that confer resistance to 3rd generation cephalosporins. SUL has also demonstrated potent in vitro activity against numerous biothreat pathogens, including Bacillus anthracis at concentrations likely to be achieved after oral dosing in humans. B. anthracis is a CDC Tier 1 Select Agent, and remains of considerable concern for biodefense. The potential for mass casualties resulting from a biothreat incident combined with the risk of antibiotic resistance necessitates development of novel medical countermeasures (MCM) for B. anthracis. Orally administered SUL was previously shown to be protective in the murine model of inhalational anthrax and provided proof-of-concept to advance the drug into the well-established rabbit model. Methods Female New Zealand White rabbits were challenged with a lethal dose of B. anthracis Ames spores via the inhalational route. Post-exposure prophylaxis (PEP) was initiated at 24 ±1 h postchallenge with cohorts (N=6) of animals receiving vehicle (saline, SC), ciprofloxacin (CIP) 10 mg/kg, SC or SUL 10 mg/kg, SC. This dosing regimen was informed by pharmacokinetic models to establish a human-equivalent dose. Treatment was continued BID for 14 days. Clinical progression and survival were assessed up to 30 days postchallenge. Results The untreated saline control group demonstrated 100% lethality with a median time to death of 48 h. Both the SUL and CIP groups demonstrated 100% survival through study termination on day 30. Conclusion As a MCM for inhalational anthrax, SUL would provide considerable advantages as an addition to the slate of current standards of care. Combined with positive efficacy results in two preclinical models of inhalational anthrax and advantages offered by an orally available penem antibiotic, SUL remains a promising candidate for advanced development for treating B. anthracis. Disclosures Sailaja Puttagunta, MD, Iterum Therapeutics: Employee|Iterum Therapeutics: Employee|Iterum Therapeutics: Stocks/Bonds (Public Company)|Iterum Therapeutics: Stocks/Bonds (Public Company) Steven I. Aronin, MD, Iterum Therapeutics: Employee|Iterum Therapeutics: Employee|Iterum Therapeutics: Stocks/Bonds (Public Company)|Iterum Therapeutics: Stocks/Bonds (Public Company)

P-1168. Activity of Isavuconazole and Comparator Agents against Pediatric Fungal Isolates Collected from 2017–2023 in a Global Surveillance Program

Abstract Background Isavuconazole (ISA) is an azole antifungal agent with desirable properties, often making it the treatment of choice for invasive fungal infections. In December 2023, ISA became the sole FDA-approved azole antifungal for the treatment of invasive aspergillosis and mucormycosis in pediatric patients as young as 1 year old. Here, we compare the in vitro activity of ISA and comparator agents against pediatric fungal isolates collected from 2017–2023 in the SENTRY Antimicrobial Surveillance Program. In vitro Activity of Isavuconazole and select comparator agents against pediatric isolates from the SENTRY database in 2017–2023 Methods A total of 851 isolates from invasive fungal infections were collected from patients ≤ 17 years old, including 284 patients ≤ 1 year old (yo), 186 2–5 yo, 204 6–12 yo, and 177 13–17 yo. The majority of isolates were from bloodstream infections (515/851, 60.5%). The second most common infection source was pneumonia in hospitalized patients (129/851, 15.2%). Antifungal susceptibility testing was performed by broth microdilution according to CLSI guidelines. Results were interpreted using epidemiological cutoff values (ECV) where applicable. Results Isolates were from 28 different countries, with 25 hospitals in North America, 25 in Europe, 13 in Asia-Pacific, and 7 in Latin America. There were 684 Candida spp., 19 other yeasts, 123 Aspergillus spp., and 25 other moulds. For ISA tested against Candida spp., the MIC50 was ≤ 0.008 mg/L and the MIC90 was 0.06 mg/L (Table 1). This result was comparable to MIC50/90 for voriconazole (VRC) against Candida spp. The fluconazole (FLC) MIC50/90 was higher at 0.25/2 mg/L. For Aspergillus spp., the MIC50/90 for ISA was 0.5/2 mg/L and 89.2% of isolates were wildtype (WT) by ECV. The VRC MIC50/90 was 0.5/1 mg/L and 95% of isolates were WT. For Mucorales, MICs were 1–8 mg/L for ISA and 4– > 8 mg/L for VRC. For all other moulds, MICs ranged from 0.25– > 8 mg/L for ISA and 0.12– > 8 mg/L for VRC. Conclusion ISA has good activity against pediatric fungal isolates from diverse geographical locations and infection sources. MICs were low for Candida spp. and Aspergillus spp., lower than FLC, and comparable to VRC. All agents had high MICs to non-Aspergillus moulds, highlighting the continued need for novel antifungal agents targeting these organisms. Disclosures Marisa Winkler, MD, PhD, Element Iowa City (JMI Laboratories) was contracted to perform services in 2023 for > 30 biotech and pharmaceutical companies: Grant/Research Support Kelley A. Fedler, BS, Paratek Pharmaceuticals: Grant/Research Support

Suggested Dosing of Select Beta-lactam Agents for the Treatment of Antimicrobial-Resistant Gram-Negative Infections in Children.

The Infectious Diseases Society of America (IDSA) publishes annual guidance on the treatment of antimicrobial-resistant (AMR) gram-negative infections. Within the AMR guidance, suggested dosages of antibiotics for adults infected with AMR pathogens are provided. This document serves as a companion document to the IDSA guidance to assist pediatric specialists with dosing β-lactam agents for the treatment of AMR infections in children. A panel of 13 pediatric infectious diseases specialists, including 11 pharmacists and two physicians, reviewed existing pharmacokinetic/pharmacodynamic, animal, and clinical data for newer β-lactam agents that are available in the United States and suggested for the treatment of AMR infections (i.e., cefiderocol, ceftazidime-avibactam, ceftazidime-avibactam & aztreonam, ceftolozane-tazobactam, imipenem-cilastatin-relebactam, meropenem-vaborbactam, sulbactam-durlobactam). Suggested dosing for ampicillin-sulbactam is also provided given complexities in appropriate dosing for carbapenem-resistant Acinetobacter baumannii infections. Consensus-based suggested dosing for β-lactam agents used to treat AMR infections in neonates, infants, children, and adolescents and relevant supporting evidence are provided. Content is up to date as of December 1st, 2024. Gaps and limitations to existing data are discussed. Optimizing antibiotic dosing is critical to improving the outcomes of children with AMR infections.

Francisella tularensis universal stress protein contributes to persistence during growth arrest and paraquat-induced superoxide stress.

Francisella tularensis is classified as a Tier 1 select agent due to the low infectious dose, ease of transmission, and potential use as a bioweapon. To better understand the stress defense mechanisms that contribute to the ability of this highly virulent pathogen to persist, we evaluated the conserved F. tularensis universal stress protein (Usp). We show that F. tularensis Usp is unusually stable and remains abundant, regardless of the stress conditions tested, differing from other bacterial Usp homologs. We also determined that F. tularensis Usp enhances the expression of several critical antioxidant defense genes and increases survival during paraquat exposure and growth arrest. Determining the factors that promote F. tularensis persistence in the environment is needed to prevent tularemia transmission.

Rapid identification of bacterial select agents using loop-mediated isothermal amplification

BackgroundPoint of need diagnostics provide efficient testing capability for remote or austere locations, decreasing the time to answer by minimizing travel or sample transport requirements. Loop-mediated isothermal amplification (LAMP) is an appealing technology for point-of-need diagnostics due to its rapid analysis time and minimal instrumentation requirements.MethodsHere, we designed and optimized nine LAMP assays that are sensitive and specific to targeted bacterial select agents including Bacillus anthracis, Francisella tularensis, Yersinia pestis, and Brucella spp. Evaluation of each assay determined preliminary limit of detection (LOD) with LOD confirmed across 60 replicates (≥ 95% positivity rate). Testing across a robust set of strains of the target agent, common DNA agents, and near-neighbors documented sensitivity and specificity for independent assays.ResultsSpecifically, all assays were 100% specific and sensitive except for Y. pestis Caf1 (90% inclusive across Y. pestis strains).ConclusionHere, we optimized assay turn-around-time, decreasing a standard 60 min traditional polymerase chain reaction (PCR) to 30 min using LAMP with positive results in as little as 5–10 min. Incorporating point of need sample processing and evaluating the potential inhibitory impact of sample matrices such as whole blood and soil would be needed to enable this test system for use on field-forward clinical and environmental sample testing.

Cryogenic Electron Microscopy of Rift Valley Fever Virus.

Rift Valley fever virus (RVFV) is an important livestock and human pathogen. It is also a potential bioweapon owing to its ability to spread by aerosols. It is an enveloped virus containing surface protrusions composed of two viral glycoproteins, Gc and Gn; the viral core contains ribonucleoprotein complexes. We describe the use of cryogenic electron microscopy (Cryo-EM) of single particles to visualize the three-dimensional (3D) organization of RVFV. The spherical RVFV virions have a diameter of 100nm with icosahedral symmetry (T=12) and 720 prominent protrusions on their surface.In this chapter we describe the general protocols to prepare virus suspensions for Cryo-EM, image acquisition of virus particles embedded in vitreous water, and their image processing. Because of RVFV being classified as a BSL3 and potentially as a select agent, we also describe the protocol of performing Cryo-EM grid preparation and imaging in our Cryo-EM BSL3 containment, along with the general etiquette of using BSL3 containment for research, including entry into containment, dressing up for work there, manipulation with the agent, grid preparation, transfer of the frozen grids into a microscope, etc., waste disposal, and finally exit from the containment. The microscope decontamination with ClO2 is briefly described as well because that technique is not widely used in the Cryo-EM field.

Exploring the antihypertensive potential of natural compounds from Zygophyllum sp plant: An in-silico investigation of ACE inhibition

Abstract Hypertension, a major contributor to global mortality, requires comprehensive management including lifestyle changes and medication. This study explores the potential of natural compounds from Zygophyllum sp as Angiotensin-converting enzyme (ACE) inhibitors, a key class of antihypertensive drugs. Using molecular docking methodology, we investigated the inhibitory effects of these compounds on the ACE enzyme (PDB: 1UZF). Our work demonstrated that several molecules exhibited promising binding scores compared to established reference ligands, suggesting potential ACE-inhibiting properties. Myristic acid showed the most favorable score (-9.2454 kcal/mol), surpassing conventional reference drugs. Geranyllinalool, Pseudophytol, Methyl linoleate and Phytol also demonstrated superior scores. 1-Octadecene and linoleic acid outperformed captopril and aligned closely with other reference ligand scores. The computational scores, largely exceeding those of established drugs, indicate strong affinities between Zygophyllum sp ’ s chemical constituents and the ACE enzyme. This suggests potential antihypertensive properties of the plant and its bioactive components, supporting its traditional use as an antihypertensive remedy. The notable efficacy scores of select known therapeutic agents further validate this potential. However, additional in-vitro and in-vivo investigations are necessary to robustly establish the ACE-inhibitory capability of Zygophyllum sp compounds. This study provides a foundation for further research into natural antihypertensive treatments, potentially offering new avenues for managing this widespread health concern.

Virulome and phylogenomic profiling of a novel Burkholderia pseudomallei strain from an Indian clinical isolate.

Highly pathogenic Burkholderia pseudomallei is the causative agent of melioidosis, a neglected tropical disease endemic in Southeast Asian tropical region. This bacterium encompasses diverse virulence factors which further undergo dynamic gene-expression flux as it transits through distinct environmental niches within the host which may lead to manifestation of differential clinical symptoms. B. pseudomallei, is classified as a Tier 1 select agent in the United States and regarded as a risk group 3 organism in India with the potential to be used as bioweapon. Considering these facts, it is vital to uncover both physiological and genetic heterogeneity of B. pseudomallei, particularly to identify any novel virulence factors that may contribute to pathogenicity. B. pseudomallei strain CM000113 was isolated from a clinical case in India, characterized it for its physiological, biochemical, and prominently genetic traits through WGS. It has a type 2 morphotype with faster doubling time and high biofilm producing capacity as compared to Pseudomonas aeruginosa. The genome size is 7.3 Mbp and it is phylogenetically close to B. pseudomallei strain Mahidol 1106a and Burkholderia mallei Turkey 2. We observed genetic heterogeneity, as key virulence factors that were identified shows sequence dissimilarity with reference strains. Additionally, presence of genomic islands, harbouring two virulence factors, GmhA and GmhB2, associated with pathogenesis indicates possibility of horizontal gene transfer. These results emphasize the need for an extensive study focusing the genome of B. pseudomallei and its associated heterogeneity, to identify molecular biomarkers aiding to develop point-of-care diagnostic kits for early diagnosis of melioidosis.

Virulence of Burkholderia pseudomallei ATS2021 Unintentionally Imported to United States in Aromatherapy Spray.

In the United States in 2021, an outbreak of 4 cases of Burkholderia pseudomallei, the etiologic agent of melioidosis and a Tier One Select Agent (potential for deliberate misuse and subsequent harm), resulted in 2 deaths. The causative strain, B. pseudomallei ATS2021, was unintentionally imported into the United States in an aromatherapy spray manufactured in India. We established that ATS2021 represents a virulent strain of B. pseudomallei capable of robust formation of biofilm at physiologic temperatures that may contribute to virulence. By using mouse melioidosis models, we determined median lethal dose estimates and analyzed the bacteriologic and histopathologic characteristics of the organism, particularly the potential neurologic pathogenesis that is probably associated with the bimABm allele identified in B. pseudomallei strain ATS2021. Our data, combined with previous case reports and the identification of endemic B. pseudomallei strains in Mississippi, support the concept that melioidosis is emerging in the United States.

Engineered antibodies targeted to bacterial surface integrate effector functions with toxin neutralization to provide superior efficacy against bacterial infections.

Anti-bacterial monoclonal antibody (mAb) therapies either rely on toxin neutralization or opsonophagocytic killing (OPK). Toxin neutralization protects the host from toxin-induced damage, while leaving the organism intact. OPK inducing antibodies clear the bacteria but leave the released toxins unencountered. Infection site targeted anti-toxin antibodies (ISTAbs) that we report here addresses this binary paradigm by combining both functionalities into a single molecule. ISTAbs consist of cell wall targeting (CWT) domains of bacteriophage endolysins fused to toxin neutralizing mAbs (IgG). CWT governs specific binding to the surface of bacteria while the IgG variable domain neutralizes the toxins as they are released. The complex is then cleared by phagocytic cells. As proof of concept, we generated several ISTAb prototypes targeting major toxins from two Gram-positive spore forming pathogens that have a high clinical significance; Clostridium difficile , causative agent of the most common hospital-acquired infection, and Bacillus anthracis , a Category A select agent pathogen. Both groups of ISTAbs exhibited potent toxin neutralization, binding to their respective bacterial cells, and induction of opsonophagocytosis. In mice infected with B. anthracis , ISTAbs exhibit significantly higher efficacy than parental IgG in both pre- and post-challenge models. Furthermore, ISTAbs fully protected against B. anthracis infection in a nonhuman primate (NHP) aerosol challenge model. These findings establish that as a platform technology, ISTAbs are broadly applicable for therapeutic intervention against several toxigenic bacterial pathogens.

Phylogenetic analyses show the Select Agent Coniothyrium glycines represents a single species that has significant morphological and genetic variation

ABSTRACT Soybean red leaf blotch (RLB), caused by the fungus Coniothyrium glycines, represents a foliar disease of soybean that is thus far restricted to Africa. The fungus is listed as a Select Agent by the Federal Select Agent Program because it could pose a severe threat to plant health were it to establish in the United States. Previous work uncovered tremendous molecular diversity at the internal transcribed spacer region, suggesting that there may be multiple species causing RLB. To determine whether multiple species cause RLB, we reconstructed the phylogeny of C. glycines and taxonomic allies using sequence data from four genes. We included 33 C. glycines isolates collected from six African countries and determined that all isolates form a well-supported, monophyletic lineage. Within this lineage there are at least six well-supported clades that largely correspond to geography, with one clade exclusively composed of isolates from Ethiopia, another exclusively composed of isolates from Uganda, and four composed of isolates from southern Africa. However, we did not detect any concordance for these clades between the four genes, indicating that all isolates included in this analysis are representative of a single species. Isolates in the Ethiopia clade are morphologically distinct from isolates in the other clades, as they produce larger sclerotia and smaller pycnida and more sclerotia in planta. Additionally, ancestral range estimations suggest that the C. glycines lineage emerged in southern Africa. These results show that there is significantly more genetic and morphological diversity than was initially suspected with this high-consequence fungal plant pathogen.

Development of a novel sandwich immunoassay based on targeting recombinant Francisella outer membrane protein A for the diagnosis of tularemia.

Tularemia, caused by the bacterium Francisella tularensis, poses health risks to humans and can spread through a variety of routes. It has also been classified as a Tier 1 Select agent by the CDC, highlighting its potential as a bioterrorism agent. Moreover, it is difficult to diagnose in a timely fashion, owing to the non-specific nature of tularemia infections. Rapid, sensitive, and accurate detection methods are required to reduce mortality rates. We aimed to develop antibodies directed against the outer membrane protein A of F. tularensis (FopA) for rapid and accurate diagnosis of tularemia. We used a baculovirus insect cell expression vector system to produce the FopA antigen and generate anti-FopA antibodies through immunization of BALB/c mice. We then employed hybridoma and phage display technologies to screen for antibodies that could recognize unique epitopes on FopA. Two monoclonal antibodies, 6B12 and 3C1, identified through phage display screening specifically bound to recombinant FopA in a dose-dependent manner. The binding affinity of the anti-FopA 6B12 and 3C1 antibodies was observed to have an equilibrium dissociation constant of 1.76 × 10-10 M and 1.32 × 10-9 M, respectively. These antibodies were used to develop a sandwich ELISA system for the diagnosis of tularemia. This assay was found to be highly specific and sensitive, with detection limits ranging from 0.062 ng/mL in PBS to 0.064 ng/mL in skim milk matrices. Our findings demonstrate the feasibility of a novel diagnostic approach for detecting F. tularensis based on targeting FopA, as opposed to existing tests that target the bacterial lipopolysaccharide.

Potency Evaluations of Recombinant Botulinum Neurotoxin A1 Mutants Designed to Reduce Toxicity.

Recombinant mutant holotoxin BoNTs (rBoNTs) are being evaluated as possible vaccines against botulism. Previously, several rBoNTs containing 2-3 amino acid mutations in the light chain (LC) showed significant decreases in toxicity (2.5-million-fold-12.5-million-fold) versus wild-type BoNT/A1, leading to their current exclusion from the Federal Select Agent list. In this study, we added four additional mutations in the receptor-binding domain, translocation domain, and enzymatic cleft to further decrease toxicity, creating 7M rBoNT/A1. Due to poor expression in E. coli, 7M rBoNT/A1 was produced in an endogenous C. botulinum expression system. This protein had higher residual toxicity (LD50: 280 ng/mouse) than previously reported for the catalytically inactive rBoNT/A1 containing only three of the mutations (>10 µg/mouse). To investigate this discrepancy, several additional rBoNT/A1 constructs containing individual sets of amino acid substitutions from 7M rBoNT/A1 and related mutations were also endogenously produced. Similarly to endogenously produced 7M rBoNT/A1, all of the endogenously produced mutants had ~100-1000-fold greater toxicity than what was reported for their original heterologous host counterparts. A combination of mutations in multiple functional domains resulted in a greater but not multiplicative reduction in toxicity. This report demonstrates the impact of production systems on residual toxicity of genetically inactivated rBoNTs.

Discovery of D8-03 as an Inhibitor of Intracellular Growth of Francisella tularensis.

Francisella tularensis is a Gram-negative facultative intracellular bacterial pathogen that is classified by the Centers for Disease Control and Prevention as a Tier 1 Select Agent. F. tularensis infection causes the disease tularemia, also known as rabbit fever. Treatment of tularemia is limited to few effective antibiotics which are associated with high relapse rates, toxicity, and potential emergence of antibiotic-resistant strains. Consequently, new therapeutic options for tularemia are needed. Through screening a focused chemical library and subsequent structure-activity relationship studies, we have discovered a new and potent inhibitor of intracellular growth of Francisella tularensis, D8-03. Importantly, D8-03 effectively reduces bacterial burden in mice infected with F. tularensis. Preliminary mechanistic investigations suggest that D8-03 works through a potentially novel host-dependent mechanism and serves as a promising lead compound for further development.

Nanodisc assembly from bacterial total lipid extracts

Nanodiscs are discoidal lipoproteins that have often been used as vehicles to study membrane proteins in their native configuration. Nanodiscs have been primarily made from synthetic lipids. However, nanodiscs also offer a format by which native lipids can be studied in their natural configuration. Here, we present a method to synthesize nanodiscs from bacterial total lipid extracts using the biothreat agent, Yersinia pestis, as a proof-of-concept. The creation of nanoparticles entirely composed of bacterial lipids supports membrane characterization and vaccine antigen discovery without the inherent safety concerns associated with live bacterial cells of this Tier 1 select agent pathogen.

NEW STRATEGIES IN COMBATING FUNGAL PATHOGENS

Background. The relevance of the research is driven by the emerging trend of increasing resistance to existing drugs for the treatment of fungal infections. Addressing this issue is only possible by developing new formulations of antifungal agents or improving existing ones; studying the mechanisms of interaction of drugs with fungal cell walls and their exopolysaccharide matrices; refining delivery methods of antifungal agents, such as DectiSomes, for maximum effectiveness and minimizing side effects; expanding understanding of the immune response mechanisms to fungal infections and developing vaccines for the prevention of these diseases. The research aims to improve methods of diagnosis, treatment, and prevention of fungal infections to enhance the quality of life for patients and reduce the overall impact of these diseases on public health. Aim: To evaluate new treatment strategies for fungal infections to increase the effectiveness of antifungal agents, reduce their toxicity, and slow down the development of resistance. Materials and Methods: The materials for this study included publications of results from contemporary scientific research on the topic. The methods used for conducting the research were: a systematic approach and analysis, literary and critical analysis. Results. Prove the prospects for developing new strategies and techniques for antifungal therapy. By analyzing the results of clinical studies, including the assessment of the effectiveness of various antifungal drugs, it is possible to determine which ones are most effective under certain conditions and for specific types of fungal infections. New methodologies based on the principle of delivering or acting directly on the target area allow reducing the overall burden on the body. Better penetration of drugs into the skin and tissues allows for better control of fungal infection and accelerated healing process. Evaluating side reactions and patient tolerance levels to different drugs helps select antifungal agents that are the safest and most comfortable to use. Conclusion. Fungal infections continue to be a serious public health problem, and the development of new treatment and prevention methods is extremely important. Overall, research in these areas can help develop new therapeutic strategies that are more effective and safer for treating fungal infections, which pose a threat to humanity.

Cancer therapy in patients with reduced kidney function.

Chronic kidney disease (CKD) and cancer constitute two major public health burdens, and both are on the rise. Moreover, the number of patients affected simultaneously by both conditions is growing. The potential nephrotoxic effect of cancer therapies is particularly important for patients with CKD, as they are also affected by several comorbidities. Therefore, administering the right therapy at the right dose for patients with decreased kidney function can represent a daunting challenge. We review in detail the renal toxicities of anticancer therapies, i.e. conventional chemotherapy, targeted therapy, immune checkpoint inhibitors and radioligand therapies, issue recommendations for patient monitoring along with guidance on when to withdraw treatment and suggest dosage guidelines for select agents in advanced stage CKD. Various electrolytes disturbances can occur as the result of the administration of anticancer agents in the patient with decreased kidney function. These patients are prone to developing hyponatremia, hyperkalemia and other metabolic abnormalities because of a decreased glomerular filtration rate. Therefore, all electrolytes, minerals and acid base status should be checked at baseline and before each administration of chemotherapeutic agents. Moreover, studies on patients on kidney replacement therapy are very limited and only single cases or small case series have been published. Therefore, clinical therapeutical decisions in cancer patients with decreased function should be made by multidisciplinary teams constituted of medical oncologists, nephrologists and other specialists. Onconephrology is an evolving and expanding subspecialty. It is crucial to consider anticancer drug treatment in these patients and offer them a chance to be treated effectively.

Peripheral vascular dysfunction and the aging brain.

Aging is the greatest non-modifiable risk factor for most diseases, including cardiovascular diseases (CVD), which remain the leading cause of mortality worldwide. Robust evidence indicates that CVD are a strong determinant for reduced brain health and all-cause dementia with advancing age. CVD are also closely linked with peripheral and cerebral vascular dysfunction, common contributors to the development and progression of all types of dementia, that are largely driven by excessive levels of oxidative stress (e.g., reactive oxygen species [ROS]). Emerging evidence suggests that several fundamental aging mechanisms (e.g., "hallmarks" of aging), including chronic low-grade inflammation, mitochondrial dysfunction, cellular senescence and deregulated nutrient sensing contribute to excessive ROS production and are common to both peripheral and cerebral vascular dysfunction. Therefore, targeting these mechanisms to reduce ROS-related oxidative stress and improve peripheral and/or cerebral vascular function may be a promising strategy to reduce dementia risk with aging. Investigating how certain lifestyle strategies (e.g., aerobic exercise and diet modulation) and/or select pharmacological agents (natural and synthetic) intersect with aging "hallmarks" to promote peripheral and/or cerebral vascular health represent a viable option for reducing dementia risk with aging. Therefore, the primary purpose of this review is to explore mechanistic links among peripheral vascular dysfunction, cerebral vascular dysfunction, and reduced brain health with aging. Such insight and assessments of non-invasive measures of peripheral and cerebral vascular health with aging might provide a new approach for assessing dementia risk in older adults.

Prime-boost vaccination combining rF1-V subunit and novel live attenuated bacterial strains protects mice from virulent aerosolized nonencapsulated Yersinia pestis

Abstract Yersinia pestis (Yp) is a security concern since it can be aerosolized and cause pneumonic plague, a rapidly progressing illness that is fatal if not treated promptly with antibiotics. There are no FDA-approved vaccines, and candidate vaccines are less effective against pneumonic than bubonic plague. The major protective vaccine antigen has been the F1 capsule protein; protection against nonencapsulated strains has been elusive. We constructed two novel live attenuated vaccine (LAV) strains on the pgm-pPst- background, which is excluded from the CDC select agent list due to established safety. These strains, Δcaf1 and ΔyopD/Δcaf1, lack F1 and may be more effective at inducing immunity against nonencapsulated strains like C12. Female BALB/c mice were immunized with a heterologous prime-boost strategy combining one subcutaneous injection of novel LAV and one of recombinant F1-V (rF1-V) subunit, then challenged with aerosolized virulent Yp C12 and monitored for survival, bacterial load, and immunological factors. Priming with rF1-V and boosting with LAV was more protective than the reverse strategy. Protection was accompanied by high antibody titers against rF1-V and rV. rF1-V prime and LAV boost also led to a higher IgG2a/IgG1 antibody ratio than the reverse, suggesting a balanced Th1/Th2 response. These data support rF1-V prime and pgm-pPst-Δcaf1 LAV boost as a promising strategy for a safe and effective vaccine against both encapsulated and nonencapsulated Yp.