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Progress in Molecular Biology and... 2024The rise of multidrug-resistant bacteria is a well-recognized threat to world health, necessitating the implementation of effective treatments. This issue has been... (Review)
Review
The rise of multidrug-resistant bacteria is a well-recognized threat to world health, necessitating the implementation of effective treatments. This issue has been identified as a top priority on the global agenda by the World Health Organization. Certain strains, such as Candida glabrata, Candida krusei, Candida lusitaniae, Candida auris, select cryptococcal species, and opportunistic Aspergillus or Fusarium species, have significant intrinsic resistance to numerous antifungal medicines. This inherent resistance and subsequent suboptimal clinical outcomes underscore the critical imperative for enhanced therapeutic alternatives and management protocols. The challenge of effectively treating fungal infections, compounded by the protracted timelines involved in developing novel drugs, underscores the pressing need to explore alternative therapeutic avenues. Among these, drug repurposing emerges as a particularly promising and expeditious solution, providing cost-effective solutions and safety benefits. In the fight against life-threatening resistant fungal infections, the idea of repurposing existing medications has encouraged research into both established and new compounds as a last-resort therapy. This chapter seeks to provide a comprehensive overview of contemporary antifungal drugs, as well as their key resistance mechanisms. Additionally, it seeks to provide insight into the antimicrobial properties of non-traditional drugs, thereby offering a holistic perspective on the evolving landscape of antifungal therapeutics.
Topics: Drug Repositioning; Humans; Antifungal Agents; Mycoses; Drug Resistance, Fungal; Animals
PubMed: 38942545
DOI: 10.1016/bs.pmbts.2024.04.002 -
Methods in Enzymology 2024The step catalyzed by terpene synthases is a well-recognized and significant bottleneck in engineered terpenoid bioproduction. Consequently, substantial efforts have...
The step catalyzed by terpene synthases is a well-recognized and significant bottleneck in engineered terpenoid bioproduction. Consequently, substantial efforts have been devoted towards increasing metabolic flux catalyzed by terpene synthases, employing strategies such as gene overexpression and protein engineering. Notably, numerous studies have demonstrated remarkable titer improvements by applying translational fusion, typically by fusing the terpene synthase with a prenyl diphosphate synthase that catalyzes the preceding step in the pathway. The main appeal of the translational fusion approach lies in its simplicity and orthogonality to other metabolic engineering tools. However, there is currently limited understanding of the underlying mechanism of flux enhancement, owing to the unpredictable and often protein-specific effects of translational fusion. In this chapter, we discuss practical considerations when engineering translationally fused terpene synthases, drawing insights from our experience and existing literature. We also provide detailed experimental workflows and protocols based on our previous work in budding yeast (Saccharomyces cerevisiae). Our intention is to encourage further research into the translational fusion of terpene synthases, anticipating that this will contribute mechanistic insights not only into the activity, behavior, and regulation of terpene synthases, but also of other enzymes.
Topics: Alkyl and Aryl Transferases; Metabolic Engineering; Saccharomyces cerevisiae; Recombinant Fusion Proteins; Terpenes; Protein Biosynthesis; Protein Engineering
PubMed: 38942501
DOI: 10.1016/bs.mie.2024.02.005 -
PDA Journal of Pharmaceutical Science... Jun 2024Microbiological contamination may cause microbial proliferation and consequently additional problems for pharmaceutical companies through production stoppage, product...
Quantitative and qualitative evaluation of microorganism profile identified in bioburden analysis in a biopharmaceutical facility in Brazil: Criteria for classification and management of results.
Microbiological contamination may cause microbial proliferation and consequently additional problems for pharmaceutical companies through production stoppage, product contamination, investigations of process deviations, out-of-specification results and product disposal. This is one of the major concerns of the regulatory health agencies. Microbiological load (bioburden) may represent a potential risk for patients if the sterilization process is not effective and/or due to the production of toxins. Although bioburden can be eliminated by terminal sterilization or filtration processes, it is important to monitor the amount and determine the identity and characteristics of the microorganisms present prior to final processing. The application of microorganism identification systems is crucial for identifying the type of contamination, which can be extremely useful for investigating. The aim of this study was to evaluate the profiles of microorganisms identified in bioburden assays from solutions, culture medias, and products (SCP) from a pharmaceutical industry facility. From 2018-2020, a total of 1,078 samples from 857 different lots of SCP were analyzed and isolated microorganisms were identified. A prefiltering step was included after March 2020, in order to reduce the bioburden before sterilizing filtration. Criteria for the definition and management of microorganisms identified were evaluated after an integrative bibliographic review, and three groups were proposed (critical, objectionable, and nonobjectionable microorganisms). For the samples that did not include prefiltering (n=636), 227 (35.7%) presented microbial growth. For those that included prefiltering, before prefiltering (n=221), 60.6% presented microbial growth, and after prefiltering, this value was reduced to 4.1%, which can be attributed to a contamination during the sampling or a wrong filtering. From the samples that presented microbial growth, 678 microorganisms were identified as bacteria and 59 as molds and yeasts. A total of 120 microorganisms (56 and 27 Gram-positive and negative bacteria, respectively, 31 yeasts, and six filamentous molds) could not be identified, and the remaining microorganisms were classified as objectionable (n=507; 82.2%), nonobjectionable (n=103; 16.7%) and critical (n=7; 1.1%). Most of the bioburden species (>80.0%) were considered objectionable microorganisms. A process for classification and management of bioburden analysis results based on a literature review of pathogenic and physiological characteristics of the microorganisms was proposed.
PubMed: 38942484
DOI: 10.5731/pdajpst.2023.012883 -
PDA Journal of Pharmaceutical Science... Jun 2024Vial and syringe filling by peristaltic pump has been widely implemented by contract manufacturing organizations and biopharmaceutical companies. Fill volume is commonly...
Vial and syringe filling by peristaltic pump has been widely implemented by contract manufacturing organizations and biopharmaceutical companies. Fill volume is commonly considered as critical quality attribute related in aseptic filling process and the variation needs to be well controlled to guarantee the safety, efficacy and consistency of drug products. However, the criteria for justifying the filling variation and underlying mechanisms that affect the variability are not fully revealed quantitatively in the literatures. This study selected filling accuracy, filling process capability and filling precision as three criteria for evaluating the filling process performance with four statistical indexes: Relative Error Mean, Critical Control Limit (Cpk ≥ 1.33), Relative Standard Deviation and Relative Moving Range Mean. The impact of liquid properties, pump tubing sizes and pump settings on above indexes were investigated using a bench-top system with a peristatic pump and a high-precision balance. The results showed that the viscosity, target fill volume, pump tubing size, pump speed, acceleration/deceleration rate and suck-back had statistical significance on the fill volume variability. Definitive Screening Design was further applied to clarify and visualize the priorities and interaction impact of above factors on fill volume variability. Stepwise approach for fill volume variability optimization and control based on predictive models was established and verified for drug product solution with viscosity between 1-23 cp and target fill volume between 0.2-2.0 mL.
PubMed: 38942483
DOI: 10.5731/pdajpst.2023.012867 -
PDA Journal of Pharmaceutical Science... Jun 2024Challenges in manufacturing of high concentration antibody formulations have seldom been discussed. These are observed mainly form late downstream operations where...
Challenges in manufacturing of high concentration antibody formulations have seldom been discussed. These are observed mainly form late downstream operations where antibody gets concentrated to its final strength, to final fill finish processing and containerization of the product. Present paper summarizes challenges typically observed in manufacturing and processing of high concentration antibody products and provides turnkey solutions to these typical challenges in order to have their consistent and robust manufacturing process. IgG1 has been used as model protein for studying the challenges and providing solutions to them. The late downstream challenges like increased viscosity limiting further concentration can be resolved by used of viscosity modifying agents in the formulation. Replacement of conventionally used 'A' screen membranes with 'D' screen or using single pass TFF can further provide advantage in targeting higher concentrations for same protein with lesser shear and aggregation. Using 0.5μm/0.2μm asymmetric or bilayered membrane instead of conventional 0.2μm membrane resulted in better flux while filtration of high concentration IgG1 formulation. In process holding time during filling operation was optimized to be <60min based on the nozzle drying time for high concentration IgG1 formulation. Appropriate control strategy of replacing filling nozzles and performing periodic fill weight check was proposed for fill finish process of high concentration IgG1 formulation.
PubMed: 38942482
DOI: 10.5731/pdajpst.2023.012873 -
PDA Journal of Pharmaceutical Science... Jun 2024Leachables in pharmaceutical products may react with biomolecule active pharmaceutical ingredients (APIs), for example, monoclonal antibodies (mAb), peptides, and...
Leachables in pharmaceutical products may react with biomolecule active pharmaceutical ingredients (APIs), for example, monoclonal antibodies (mAb), peptides, and ribonucleic acids (RNA), potentially compromising product safety and efficacy or impacting quality attributes. This investigation explored a series of models to screen extractables and leachables to assess their possible reactivity with biomolecules. These models were applied to collections of known leachables to identify functional and structural chemical classes likely to be flagged by these approaches. Flagged leachable functional classes included antimicrobials, colorants, and film-forming agents, whereas specific chemical classes included epoxides, acrylates, and quinones. In addition, a dataset of 22 leachables with experimental data indicating their interaction with insulin glargine was used to evaluate whether one or more methods are fit-for-purpose as a preliminary screen for assessing this biomolecule reactivity. Analysis of the data showed that the sensitivity of an screen using multiple methodologies was 80%-90% and the specificity was 58%-92%. A workflow supporting the use of methods in this field is proposed based on both the results from this assessment and best practices in the field of computational modeling and quality risk management.
Topics: Computer Simulation; Drug Contamination; Pharmaceutical Preparations; Antibodies, Monoclonal
PubMed: 38942477
DOI: 10.5731/pdajpst.2022.012818 -
Letters in Applied Microbiology Jun 2024The increasing resistance to polymyxins in Acinetobacter baumannii has made it even more urgent to develop new treatments. Anti-virulence compounds have been researched...
The increasing resistance to polymyxins in Acinetobacter baumannii has made it even more urgent to develop new treatments. Anti-virulence compounds have been researched as a new solution. Here, we evaluated the modification of virulence features of A. baumannii after acquiring resistance to polymyxin B. The results showed lineages attaining unstable resistance to polymyxin B, except for Ab7 (A. baumannii polymyxin B resistant lineage), which showed stable resistance without an associated fitness cost. Analysis of virulence by a murine sepsis model indicated diminished virulence in Ab7 (A. baumannii polymyxin B resistant lineage) compared with Ab0 (A. baumannii polymyxin B susceptible lineage). Similarly, downregulation of virulence genes was observed by qPCR at 1 and 3 h of growth. However, an increase in bauE, abaI, and pgAB expression was observed after 6 h of growth. Comparison analysis of Ab0, Ab7, and Pseudomonas aeruginosa suggested no biofilm formation by Ab7. In general, although a decrease in virulence was observed in Ab7 when compared to Ab0, some virulence feature that enables infection could be maintained. In light of this, virulence genes bauE, abaI, and pgAB showed a potential relevance in the maintenance of virulence in polymyxin B-resistant strains, making them promising anti-virulence targets.
PubMed: 38942450
DOI: 10.1093/lambio/ovae061 -
International Journal of Biological... Jun 2024Cellulose modified hydrogels can be produced directly from raw biopolymers in novel cellulose solvents such as NaOH/urea aqueous solution. The effect of cellulose...
Cellulose modified hydrogels can be produced directly from raw biopolymers in novel cellulose solvents such as NaOH/urea aqueous solution. The effect of cellulose characteristics on the synthesis of a cellulose-graft-(net-poly(acrylamide-co-acrylic acid)) and its performance as water absorbent/methylene blue dye removal material is analyzed. Three cellulose samples, one analytical grade and two obtained from teak wood sawdust with different pretreatments (one alkaline and the other, a novel one known as (gas phase) acid pretreatment) were compared. The starting raw celluloses were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and viscosity in cupri ethylenediamine hydroxide (CED) solution, whereas the chemically modified materials were characterized by SEM, FTIR, and TGA. The pretreatment used influences composition, crystallinity index and degree of polymerization (DP) of the cellulose obtained. The modified material produced with cellulose from alkaline pretreatment showed the highest swelling ratio in water absorption tests at room temperature (12,714 %); in contrast, the one with cellulose from acid pretreatment showed the lowest swelling ratio (7470 %). However, this difference is not so significative in dye removal tests, where absorption capacity is 139 and 140 mg/g, respectively. The results indicate that cellulose composition, particularly structures with significant hemicellulose and lignin remaining content, has a major effect on the performance of modified materials for water absorption, and degree of polymerization has a major effect on adsorption capacity of methylene blue.
PubMed: 38942409
DOI: 10.1016/j.ijbiomac.2024.133482 -
International Journal of Biological... Jun 2024Thiosulfate has been considered as a more environmentally-friendly alternative to cyanide salts for the extraction of gold from gold ores and the development of...
Thiosulfate has been considered as a more environmentally-friendly alternative to cyanide salts for the extraction of gold from gold ores and the development of affordable, green and efficient adsorbents for the isolation of gold-thiosulfate complex (Au(SO)) from the leaching solution remains a significant challenge. To address this issue, chitosan, a natural macromolecule, was selected as a carrier and chemically modified with ionic liquids. The ionic liquids modified chitosan showed greater adsorption capacity towards Au(SO) compared with pristine chitosan. The adsorption of Au(SO) on ionic liquid modified chitosan followed Freundlich isotherm and pseudo-second order kinetic models, involving an anion-exchange mechanism with liquid film diffusion as the rate-limiting step. The chitosan modified with butylimidazolium-based ionic liquid modified had an adsorption capacity of 5.0 mg g for Au(SO) (10 mg L, pH 6, 2 g L of adsorbent dosage), outperforming other reported adsorbents. The ionic liquid modified chitosan showed a high adsorption efficiency of up to 96.7 % for Au(SO) in an actual thiosulfate leaching solution with a desorption efficiency of 98.4 %, suggesting that the ionic liquid modified chitosan has the potential to be a eco-friendly, biocompatible and effective adsorbent for the recovery of Au(SO).
PubMed: 38942407
DOI: 10.1016/j.ijbiomac.2024.133481 -
Urology Jun 2024To present an ex-vivo bovine model for retrograde intrarenal surgery (RIRS) training.
OBJECTIVES
To present an ex-vivo bovine model for retrograde intrarenal surgery (RIRS) training.
MATERIALS AND METHODS
The model was specifically developed for a pre-congress course organized as part of the National Pediatric Urology Congress. The course involved a two-day online theoretical segment followed by hands-on training. Bovine kidneys were chosen for their anatomical resemblance to human kidneys. The kidneys were sourced from a local slaughterhouse, ensuring the intactness of the pelvis, ureters, and perirenal fat. A Modified Larssen solution was used for tissue preservation. The tissue was positioned within a cardboard box, with specific preparation techniques to ensure realism. During the hands-on training, participants utilized a flexible ureterorenoscope for practice. After the course, participants completed an 18-question survey assessing the model and training experience.
RESULTS
24 participants completed the training and survey. Four out of eight procured kidneys were suitable. The model's cost was 18 euros. 87.5% of participants reported increased RIRS confidence. Those with prior course experience rated the model's anatomical resemblance higher (p=0.016). No significant difference was observed in feedback on the model's durability or tactile feedback based on prior experience (p>0.05).
CONCLUSION
The ex-vivo bovine model provides a promising alternative for RIRS training. While further studies are needed to validate its widespread application, initial feedback suggests it offers a balance between cost-effectiveness and realistic training experience.
PubMed: 38942389
DOI: 10.1016/j.urology.2024.06.053