Biomedical Sciences Research Articles

A-308 Placental Growth Factor Kryptor Immunoassay Reveals Quality Control Imprecision and Drift

Abstract Background The utility and value of determining the soluble fms-like tyrosine kinase-1 to placental growth factor (sFlt-1/PlGF) ratio for predicting the likelihood of progression to pre-eclampsia in pregnant women admitted with hypertension are increasingly becoming widely recognized. A key finding of the multi-center PRAECIS trial (NEJM Evid 2022;1(12)) is the observation that sFlt-1/PlGF ratios ≥ 40 correlate with higher risk for adverse maternal outcomes. The sFlt-1 and PlGF immunoassays performed on the ThermoFisher Scientific B·R·A·H·M·S Kryptor autoanalyzer became the first FDA-approved tests in 2023 for determining sFlt-1/PlGF ratio. In this study, an evaluation of the analytical performance of the sFlt-1 and PlGF KRYPTOR immunoassays was performed, which included analyte measuring range (AMR), accuracy, precision, and stability studies. Methods Calibration and QC materials (consisting of lyophilized recombinant human proteins), test reagents and solutions, and consumables were purchased and provided by ThermoFisher Scientific. Analytical runs were performed according to vendor’s instructions by trained medical laboratory scientists. Between-day precision of our two instruments for both immunoassays was assessed by assaying all three levels of sFlt-1 and PlGF QC materials, as well as patient serum pools with low PlGF concentration, once to twice daily for multiple consecutive days. Results While the analytical performance of the sFlt-1 immunoassay was robust and performed according to expectation (within-day CV <1% and between-day CV <3%), the PlGF immunoassay was surprisingly less reliable. Imprecision and inaccuracy of the PlGF immunoassay at the low end of its analytical measurement range was reflected by both sporadically out-of-control between-day measurements of all three QC levels (with target ranges of 24 - 36 pg/mL, 80 - 120 pg/mL, and 320 - 480 pg/mL), as well as slow downward drifts of particularly the low level QC material. In one instance, a downtrend was observed from 28 pg/mL to 14 pg/mL over 6 days, even with fresh reagents, solutions, and calibration. Such shortened stability of the PlGF assay does not meet the vendor’s claims of calibration stability of 15 days and onboard kit stability of 29 days. Using vendor’s provided material, the AMR of both sFlt-1 and PlGF were adequately verified and showed excellent linearity (r2> 0.99). Conclusions Despite low level QC imprecision and drift, the sFlt-1/PlGF ratios determined using the B·R·A·H·M·S Kryptor analyzers are acceptable for clinical use but with the caveat that we will perform batch testing with bracketing QCs and conduct stringent QC monitoring, frequent calibrations, and reduce the onboard kit stability as defined by ThermoFisher Scientific. Our findings serve as a reminder that FDA approval does not preclude thorough verification studies of any assay prior to implementation for clinical use.

The Role of the Biomedical and Pharmaceutical Sciences in Pharmacy Education and Practice

A current major topic of conversation in academic pharmacy is "curricular hoarding", the overloading of the curriculum due to the steady addition of required knowledge and skills without a concomitant subtraction of existing content. It can be tempting to consider addressing hoarding by just reducing content in the foundational biomedical and pharmaceutical sciences, or by shifting some foundational content into prerequisites for admission into the Doctor of Pharmacy program. The healthcare education literature suggests that this approach would negatively impact the development of the critical and clinical thinking skills needed by a modern pharmacist. This commentary is intended to inform conversations on curricular hoarding by affirming and demonstrating the reliance of pharmacists' clinical and critical thinking on the scientific concepts of the biomedical and pharmaceutical science disciplines, and reiterating the importance to the practicing pharmacist of a deep understanding of these concepts, conferred through a careful and intentional educational integration.

Advances in the study of the biological activity of polysaccharide-based carbon dots: A review.

Carbon dots have attracted worldwide interest due to their customizable nature, luminescent properties, and exceptional biocompatibility. In particular, biomass-derived carbon dots have attracted attention for their environmentally friendly and cost-effective synthesis. Recent research looks into how polysaccharides can be used to make carbon dots. Using them as starting materials for nanomaterials has benefits in terms of structure, morphology, and doping elements. Although research has extensively examined the optical properties of carbon dots, their potential biological applications have not been thoroughly investigated. This review mainly summarises the cytotoxicity and biological functions of polysaccharide-based carbon dots (e.g. agar, alginate, cellulose, carrageenan, chitosan, chitosan, starch, gelatin, etc.), such as antioxidant, antibacterial and anti-tumor functions, highlighting the different scenarios of the methods of preparation of carbon dots. The applications of carbon dots in food, biomedical sciences, soil fertilization, and power generation are highlighted by reviewing the low toxicity of carbon dots with safety and biocompatibility in human contact. Finally, the importance and challenges of polysaccharide-based carbon dots and the prospects and research directions of polysaccharide-based carbon dots are explained by comparing them with other nanomaterials.

Mechanism underlying V-type structure formation in maize starch through glycerol–ethanol thermal substitution method

V-type starches have been widely used in food science, agriculture, and biomedical science, but their mechanism of formation in nonaqueous solvents remains unclear. This study performed glycerol–ethanol thermal substitution to prepare V-type starch at atmospheric pressure. Scanning electron microscopy and confocal laser scanning microscopy revealed that breakage of starch particles began in the hilum region and rapidly spread to the periphery with the temperature increased from 100 °C to 130 °C. The Maltese crosses of the starch disappeared and starch particles had the form of doughnut-shaped rings when the glycerol temperature was 140 °C. Glycerol temperature was not found to significantly affect the chain length of amylopectin, meaning that glycerol molecules may stabilize the conformation of amylose through hydrogen bonding, promoting the amylose to form a V-type spiral structure. Additionally, A-type crystallinity and double helix structure proportion of the samples significantly decreased from 30.81 % and 42.21 % to 5.70 % and 16.47 % as the temperature of glycerol was increased to 140 °C, whereas the V-type crystallinity and single helix structure proportion of the samples remarkably increased from 13.26 % and 1.05 % to 37.97 % and 25.09 %, respectively. This study provided a facile and versatile approach to effectively regulate the formation of V-type starch.

Hybridization of Machine Learning Model with Bee Colony based Feature Selection for Medical Data Classification

Nowadays, an important count of biomedical data is created continuously in several biomedical equipment and experiments because of quick technical enhancements in biomedical science. The study of clinical and health data is vital to enhance the analysis precision, prevention, and treatment. Initial analysis and treatment are extremely important approaches for preventing deaths in many diseases. Accordingly, the data mining and machine learning (ML) approaches are helpful tools for utilizing minimization error and for providing helpful data for analysis. But the data obtained in digital machines takes higher dimensionality, and not every data attained in digital machines is significant to specific diseases. This article develops an artificial bee colony-based feature selection with optimal hybrid ML model for medical data classification (ABCFS-OHML) technique. The presented ABCFS-OHML technique mainly aims to identify and classify the presence of disease using medical data. To attain this, the presented ABCFS-OHML technique initially pre-processes the input data in two ways namely null value removal and data transformation. Furthermore, the presented ABCFS-OHML technique uses ABCFS model for the choice of effectual subset of features. At last, root means square propagation with convolutional neural network-Hop field neural network (CNN-HFNN) model for classification purposes. The usage of RMSProp optimizer assists in attaining optimal hyperparameter selection of the CNN-HFNN method. The performance validation of the ABCFS-OHML technique takes place using three medical datasets. The comparison study reported that the ABCFS-OHML technique has accurately classified the medical data over other recent approaches.

Malabou, Medicine and Film: Screening Brain Injury, Organ Transplantation and Plasticity in Katell Quillévéré's Heal the Living

This article brings Catherine Malabou's explorations of bodily mutation and metamorphosis at the intersections of philosophy and biomedical science into contact with film. In particular, it explores dialogues between Malabou's work on biomedical understandings of bodily plasticity and filmic representations of medical interventions in the body. This article specifically explores Malabou in relation to Katell Quillévéré's film Heal the Living ( Réparer les vivants, 2016), an adaptation of Maylis de Kerangal's novel The Heart ( Réparer les vivants, 2014). The film tells the story of Simon Limbres, who is taken to a hospital following a road accent and pronounced brain dead. The film then explores how Simon undergoes organ donation, following his organs on their journey to other bodies in need. I argue that Heal the Living allows us to challenge and extend Malabou's central thinking of (neuro)plasticity, precisely by emphasising the plasticity of the body beyond and in the wake of the brain. Further, the film's emphasis on transplantation allows for an exploration of interpersonal plasticity, developing an ethics of transplanted plasticity in testing and extending conceptions of otherness and alterity central to Malabou's thinking.

Characterization of population connectivity for enhanced cross-border surveillance of yellow fever at Mutukula and Namanga borders in Tanzania

IntroductionYellow fever (YF) remains a public health threat in Sub-Saharan Africa and South America with an estimated 200,000 cases and 30,000 deaths annually. Although the World Health Organization considers Tanzania as low risk for YF because no YF cases have been reported, the country remains at alert to importation of the virus due to ecological factors and high connectivity to high-risk YF areas in other countries. PurposeThis study aimed to identify points of interest with connectivity to high-risk YF areas to guide preparedness efforts in Tanzania. MethodsUsing the Population Connectivity Across Borders toolkit, the Nelson Mandela African Institution of Science and Technology (Department of Health and Biomedical Sciences) in collaboration with the Tanzania Ministry of Health and the Centers for Disease Control and Prevention implemented 12 focus group discussions with participatory mapping in two high-risk borders of Mutukula and Namanga. ResultsParticipants identified 147 and 90 points of interest with connectivity to YF risk areas in Kenya and Uganda, respectively. The identified locations are important for trade, fishing, pastoralism, tourism, health-seeking, agriculture, mining, religious activities, education, and cross-border marriages. ConclusionThe Tanzania Ministry of Health used the results to update cross-border surveillance and risk communication strategies and vaccination guidelines to prevent the importation of YF into Tanzania.

Flexible Single Microwire X-Ray Detector with Ultrahigh Sensitivity for Portable Radiation Detection System.

Sensitive, flexible, and low false alarm rate X-ray detector is crucial for medical diagnosis, industrial inspection, and scientific research. However, most semiconductors for X-ray detectors are susceptible to interference from ambient light, and their high thickness hinders their application in wearable electronics. Herein, a flexible visible-blind and ultraviolet-blind X-ray detector based on Indium-doped Gallium oxide (Ga2O3:In) single microwire is prepared. Joint experiment-theory characterizations reveal that the Ga2O3:In microwire possess a high crystal quality, large band gap, and satisfactory stability, and reliability. On this basis, an extraordinary sensitivity of 5.9×105µCGyair -1cm-2 and a low detection limit of 67.4nGyairs-1 are achieved based on the prepared Ag/Ga2O3:In/Ag device, which has outstanding operation stability and excellent high temperature stability. Taking advantage of the flexible properties of the single microwire, a portable X-ray detection system is demonstrated that shows the potential to adapt to flexible and lightweight formats. The proposed X-ray detection system enables real-time monitor for X-rays, which can be displayed on the user interface. More importantly, it has excellent resistance to natural light interference, showing a low false alarm rate. This work provides a feasible method for exploring high-performance flexible integrated micro/nano X-ray detection devices.

Eco‐friendly Green Synthesis of Silver Nanoparticles Using Daphne Mucronata Royle Seeds Extract and the Potential Antibacterial, Antifungal, and Scolicidal Activities

AbstractGreen synthesized silver nanoparticles (AgNPs) have received lots of attention due to being used as potential therapeutic agents. For the first time, this research investigated the biosynthesis of silver nanoparticles using the extract of Daphne mucronata seeds, which are rich in phenolic and polyphenolic substances and evaluated their antibacterial, antifungal, and scavenging activities. The process of nanoparticle (NPs) preparation was confirmed using UV–vis spectroscopy with an absorption peak at a wavelength of 440 nm. Dynamic light scattering (DLS) was used to determine the particles' distribution. Fourier‐transform infrared spectroscopy (FTIR) validated the functional groups contributing to the reduction of Ag+ to Ag. Moreover, X‐ray diffraction analysis (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) approved the crystalline nature and spherical shape of the particles with mean and standard deviation of particle size to be 60.25 and 24.88 nm, respectively. The antibacterial, antifungal, and scolicidal activities of AgNPs were studied using disc diffusion against four standard bacteria species and microdilution methods for four Candida strains. The greatest effect of AgNPs with the highest concentration (80 µg/mL) was observed on Staphylococcus aureus (22.26 mm) and the lowest on Pseudomonas aeruginosa (19.07 mm). In the case of Candida fungus, the highest effect of AgNPs was reported for Candida krusei (7.93 µg/mL) and the lowest for Candida albicans (63.49 µg/mL). Also, these nanoparticles were able to register 100% lethality on the Echinococcus granulosus parasite in 15 min at a concentration (80 µg/mL). Therefore, the production of AgNPs as a renewable and cheap material can be effective after performing all the necessary tests as antibacterial, antifungal and antiparasitic agents with the least side effects in biomedical and pharmaceutical sciences.

Vascular fibrosis and extracellular matrix remodelling in post-COVID 19 conditions

Causal associations between viral infections and acute myocardial injury are not fully understood, with mechanisms potentially involving direct cardiovascular involvement or systemic inflammation. This review explores plausible mechanisms of vascular fibrosis in patients with post-COVID-19 syndrome, focusing on extracellular matrix remodelling. Despite global attention, significant mechanistic or translational breakthroughs in the management of post-viral syndromes remain limited. No effective pharmacological or non-pharmacological interventions are currently available for patients experiencing persistent symptoms following COVID-19 infection. The substantial expansion of scientific knowledge resulting from collaborative efforts by medical experts, scientists, and government organisations in undertaking COVID-19 research could inform treatment strategies for other post-viral syndromes and respiratory illnesses. There is a critical need for clinical trials to evaluate potential therapeutic candidates, providing evidence to guide treatment decisions for post-COVID-19 syndromes.

Proceedings of the 2022 "Lifestyle Intervention for Epilepsy (LIFE)" symposium hosted by Cleveland Clinic.

Lifestyle interventions are strategies used to self-manage medical conditions, such as epilepsy, and often complement traditional pharmacologic and surgical therapies. The need for integrating evidence-based lifestyle interventions into mainstream medicine for the treatment of epilepsy is evident given that despite the availability of a multitude of treatments with medications and surgical techniques, a significant proportion of patients have refractory seizures, and even those who are seizure-free report significant adverse effects with current treatments. Although the evidence base for complementary medicine is less robust than it is for traditional forms of medicine, the evidence to date suggests that several forms of complementary medicine including yoga, mindfulness meditation, cognitive behavioral therapy, diet and nutrition, exercise and memory rehabilitation, and music therapy may have important roles as adjuncts in the treatment armamentarium for epilepsy. These topics were discussed by a diverse group of medical providers and scientists at the "Lifestyle Intervention for Epilepsy (LIFE)" symposium hosted by Cleveland Clinic. PLAIN LANGUAGE SUMMARY: There are many people with epilepsy who continue to have seizures even though they are being treated with medication or brain surgery. Even after seizures stop, some may experience medication side effects. There is research to suggest that certain lifestyle changes, such as yoga, mindfulness, exercise, music therapy, and adjustments to diet, could help people with epilepsy, when used along with routine treatment. Experts discussed the latest research at the "Lifestyle Intervention for Epilepsy (LIFE)" symposium hosted by Cleveland Clinic.

3D Tumor-Engineered Model Replicating the Osteosarcoma Stem Cell Niche and In Vivo Tumor Complexity.

Osteosarcoma, among all bone sarcomas, remains a challenge despite the unwavering efforts of medical professionals and scientists. To address this, the scientific community is actively pursuing the development of three-dimensional (3D) in vitro models to faithfully replicate the heterogeneity of osteosarcoma, thereby facilitating the reliable preclinical screening of potential therapies. In this study, we present the latest advancements in engineering an in vitro 3D osteosarcoma model comprising enriched Cancer Stem Cells (CSCs) and a hybrid hydroxyapatite-based scaffold (MgHA/CoII). The improvement of the model occurred through two primary steps: (1) serial passaging of sarcospheres as the CSCs enrichment system and (2) the optimization of the structural configuration of the niche in the scaffold. Two injection-mediated approaches of sarcosphere seeding were designed and extensively characterized in vitro and in vivo Chorioallantoic Membrane (CAM) models to explore their biological properties and tumorigenic potential. The combination of the selected enriched-CSCs and custom-made seeding into the scaffold resulted in the development of 3D osteosarcoma models exhibiting tumor-like features in vitro and tumorigenic properties in vivo. The outcomes of this study offer prospects for future endeavors involving more complex systems capable of replicating specific malignant tumor behaviors (metastatic process and drug resistance), pushing the discovery of new therapeutic strategies for clinical applications.

Biochemical, Immunological Markers, Histology and Ultrastructural Changes of Open Wound Healing in Rats Treated with Ethyl Acetate Extract of Zingiber zerumbet Rhizomes.

Research on plant-based wound healing agents has been one of the current developing areas in modern biomedical science. This study aimed to assess the effects of ethyl acetate extract of Zingiber zerumbet rhizome (ZZRE) on open wound healing activity in Wistar rats. Ninety male Wistar rats (220-320 g) were divided into three groups treated with phosphate buffered saline (PBS) (negative control), Solcoseryl gel (positive control), and 10% ZZRE (treatment group), respectively. Six circular full-skin thickness wounds of 6.0 mm in diameter were induced bilaterally on the dorsal surface of each rat. Six rats were sacrificed on Day-1, Day-3, Day-6, Day-10 and Day-14 respectively from each group after wound induction. All data obtained are considered statistically significant at p < 0.05. Macroscopic observations showed that the 10% ZZRE treated wounds healed faster compared to other groups. The wound closure percentage showed that the wound treated with 10% ZZRE is significantly higher (p<0.05) than the PBS group on Day-6, Day-10 and Day-14. Protein levels of the 10% ZZRE group decreased significantly at Day-1 compared to the PBS group and significantly (p<0.05) higher at Day-14 compared to both control groups. The hexosamine and uronic acid levels of the 10% ZZRE group showed a significant (p < 0.05) decrease on Day-14. Conversely, hydroxyproline levels showed significant (p < 0.05) increase starting from Day-3 until Day-14. As for the immunological markers, the level of total TGF-β1 of the 10% ZZRE group was significantly (p < 0.05) higher than the PBS group on Day-14, whereas the level of IL-10 on the wound tissue of the 10% ZZRE group was significantly (p < 0.05) lower than the PBS group on Day-1 but significantly (p < 0.05) higher on Day-10 and Day-14 compared to both control groups. Histological observation showed that the wounds treated with 10% ZZRE infiltrated with lesser inflammatory cells while collagen deposition was denser as compared to both control groups. Based on the result obtained, it is clearly proven that treatment of 10% ZZRE on open wound healing in rats, showed that the extract was effective in healing the wound and accelerated the healing process. Therefore, the 10% ZZRE tested has the potential to be developed as an alternative wound healing agent in the future.

Alpha-calcium sulfate hemihydrate incorporated with tri-calcium phosphate and hydroxyapatite bioceramics as potential scaffold for bone regeneration

The development of artificial grafts, including biodegradable materials and non-biodegradable ones, for bone regeneration is a significant advance in the field of biomaterial science. Notably, bioceramics such as calcium sulfate hemihydrate and calcium phosphates have attracted extensive attention from researchers due to their natural bone-like composition. However, some requirements related to mechanical properties, resorption ability, osteoinduction and osteoconduction of each bioceramics have not been effectively controlled to make them ideal materials for bone regeneration applications. In this study, composites of β-tricalcium phosphate, hydroxyapatite, and α-calcium sulfate hemihydrate (β-TCP/HA/α-CSH) were synthesized using wet mixing method in order to create a template that degrades in sync with bone growth, offer sufficient mechanical strength during healing process, and has appropriate setting time for precise surgical application. The β-TCP/HA compositional phase with the ratio of 80/20 (% in weight) would be used for the entire study meanwhile the influence of α-CSH on the behaviour of β-TCP/HA/α-CSH composites would be investigated. The successful preparation of β-TCP/HA/α-CSH composite was evaluated by FTIR, XRD, and SEM. In vitro testing has further demonstrated the commendable biodegradability of β-TCP/HA/α-CSH composites and its ability for cell adhesion and migration, suggesting that β-TCP/HA/α-CSH composites would be a promising biomaterial for bone engineering.

Synthesis of low-dimensional metal halide CsAgCl2 for X-ray scintillation applications

Low-dimensional metal halides, which possess efficient luminescent properties, have garnered significant interest in the fields of optoelectronics and radiation detection. This study introduces novel lead-free silver-based metal halide material, CsAgCl2 microcrystals (MCs). These MCs have a one-dimensional atomic chain structure and a unique [AgCl5]4- tetragonal shared triangular configuration. CsAgCl2 MCs exhibit excellent performance as X-ray scintillators due to their bright broadband yellow emission and fast decay time in the microsecond range. The large Stokes shift of 350 nm is produced by self-trapped exciton emission. In X-ray scintillation applications, CsAgCl2 MCs demonstrate a high light yield of 13280 photons/MeV and a wide range of linear scintillation response. It is noteworthy that the CsAgCl2 MCs maintain good stability under both atmospheric conditions and continuous X-ray irradiation. The sample was used in an X-ray imaging screen, which clearly presented the X-ray projection image of a wooden stick. As a result, this research not only contributes to the collection of lead-free metal halide scintillators but also indicates that CsAgCl2 MCs have a wide range of future applications and potential in areas such as medical imaging, scientific research, and diagnostic and detection technologies.

Environmental and patient safety: Advances in radiological techniques to reduce radiation exposure

The growing concern for environmental and patient safety in medical imaging has driven significant advancements in radiological techniques aimed at reducing radiation exposure. This review explores these developments, emphasizing the dual focus on minimizing harm to patients and addressing the broader environmental impact of radiological practices. Recent innovations include the optimization of imaging protocols, the introduction of low-dose imaging technologies, and the integration of advanced software algorithms that enhance image quality while reducing the need for higher radiation doses. The implementation of iterative reconstruction techniques, for instance, has allowed for significant dose reductions in computed tomography (CT) scans without compromising diagnostic accuracy. Additionally, the use of alternative imaging modalities such as magnetic resonance imaging (MRI) and ultrasound, which do not involve ionizing radiation, is increasingly recommended where clinically appropriate, further mitigating radiation risks. Furthermore, the shift towards personalized imaging protocols, where radiation doses are adjusted based on individual patient characteristics, marks a critical advance in patient safety. This approach not only reduces unnecessary exposure but also enhances the overall effectiveness of diagnostic procedures. Environmental safety considerations have also led to the development of more sustainable radiological practices, including the safe disposal of radioactive materials and the reduction of energy consumption in imaging facilities. These efforts are aligned with broader healthcare initiatives to lower the carbon footprint of medical practices. The advancements in radiological techniques to reduce radiation exposure reflect a growing commitment to patient-centered care and environmental stewardship in healthcare. As technology continues to evolve, ongoing research and collaboration between medical professionals, physicists, and environmental scientists will be crucial in furthering these goals. By continuing to innovate and implement safer radiological practices, the medical community can significantly mitigate the risks associated with radiation exposure, ensuring better health outcomes for patients and reducing the environmental impact of radiological services.

Grit and Optimism Predict Academic Performance Among Medical and Health Sciences Students at a Malaysian University: A Cross-sectional Study

Grit is the perseverance and passion for long-term goals, optimism represents an individual’s expectation of a positive outcome in most situations, whereas life satisfaction is a major indicator of well-being. Grit, optimism, and life satisfaction play a role in medical and health science education, as they are associated with academic performance. This cross-sectional study explored the relationship between grit, optimism, and life satisfaction among medical and health sciences students at a Malaysian university using the 12-Item Grit Scale, Life Orientation Test-Revised (LOT-R) scale and Satisfaction with Life Scale (SWLS). Medical students were significantly grittier than optometry students (p = 0.015) and significantly more optimistic than biomedical science students (p = 0.007). Academic performance was significantly correlated with grit (r = 0.135, p = 0.027) and optimism (r = 0.139, p = 0.023). On the other hand, a significant correlation existed between grit and optimism (r = 0.316, p = 0.000) as well as optimism and life satisfaction (r = 0.328, p = 0.000), whereas a correlation was observed between grit and life satisfaction (r = 0.171, p = 0.003). The findings show that interdisciplinary differences in grit and optimism exist and that grit and optimism are related to the academic performance of medical and health sciences students. Grit, optimism, and life satisfaction were interrelated in this study.

Synergistic effects of Psidium guajava and procaine penicillin on MRSA, MSSA and E. faecalis

Background: Antibiotic resistance is a significant public health challenge, exacerbated by resistant strains such as methicillin-resistant Staphylococcus aureus (MRSA).Aim: This study investigates the synergistic antibacterial effects of Psidium guajava aqueous extract combined with procaine penicillin against MRSA, methicillin-sensitive S. aureus (MSSA) and Enterococcus faecalis.Setting: In-vitro study conducted under controlled laboratory settings at the Mangosuthu University of Technology, Department of Biomedical Sciences, Kwa-Zulu Natal, South Africa.Methods: Psidium guajava leaves were collected and prepared according to the German Homeopathic Pharmacopoeia, while procaine penicillin was diluted for testing. The combination treatment was evaluated using the Kirby–Bauer Antimicrobial Sensitivity Test and Minimum Inhibitory Concentration (MIC) assays.Results: Results showed that the combination of P. guajava extract and procaine penicillin significantly enhanced the antibacterial activity against MRSA, as evidenced by larger zones of inhibition and lower MIC values compared to P. guajava extract and procaine penicillin on their own. However, no significant difference was observed against MSSA and E. faecalis.Conclusion: The findings suggest that P. guajava extract could potentiate the efficacy of procaine penicillin against MRSA, providing a potential alternative strategy to combat antibiotic-resistant bacteria.Contribution: The study revealed that P. guajava aqueous extract enhances the antibacterial efficacy of procaine penicillin specifically against MRSA, suggesting a potential alternative treatment strategy for antibiotic-resistant infections, validated through robust methods and highlighting the need for further research to understand the mechanisms and clinical applications.

Vat photopolymerization of ultra-porous bioactive glass foams

The introduction of additive manufacturing technologies in the field of biomaterials science has opened new horizons for regenerative medicine. In this work, we pushed the potential of vat polymerization to the limit for fabricating ultra-porous bioactive SiO2-CaO-MgO-P2O5-CaF2-Na2O glass scaffolds with bone-like architectural characteristics. The tomographic reconstruction of an open-cell foam was used as input file to the printing system and reliably reproduced in all its exquisite details, as assessed by morphological analyses of sintered scaffolds (thickness of single struts 35 μm, exceptionally high porosity around 94 vol%, most pores with size from 500 to 900 μm). Immersion studies in simulated body fluid (SBF) revealed the apatite-forming ability (i.e., in vitro bioactivity) of the scaffolds, the surface of which started being coated by calcium phosphate after just 3 days from the beginning of the experiments. Taken together, these results show great promise for application of such scaffolds in bone defect repair.

A simulation-based analysis of optical read-out for electrochemical reactions using composite vortex beams.

We propose an optical read-out method for extracting faradaic current in electrochemical (EC) reactions and analyze its performance using opto-EC simulations. Our approach utilizes structured electrodes to generate composite optical vortex (COV) beams upon optical illumination. Through opto-EC simulations, we demonstrate that the EC reaction of 10 mM potassium ferricyanide induces a refractive index (RI) change, RI, of approximately RI units, leading to the rotation of the COV beam's intensity profile with a peak rotation of . This rotation's magnitude is proportional to RI, while the rate correlates with the faradaic current ( ) density responsible for RI. As the opto-EC information is from bulk RI, it remains unaffected by interfering non-faradaic components at the interface and is advantageous for studying intermediate species and bulk homogeneous reactions. Furthermore, as rotation depends on density rather than itself, this method proves beneficial in low scenarios, such as when employing micro-electrodes to decrease solution resistance or obtain localized EC data. Even in low density scenarios, like monitoring slow EC reactions, our method enables signal amplification by accumulating rotation over time. This interdisciplinary approach holds promise for advancing EC research and addressing critical challenges across various fields, including energy storage, corrosion protection, environmental remediation, and biomedical sciences.