Search Results (817)

Ensuring bacterial safety of blood transfusions remains a critical focus in medicine. We investigated a novel pathogen reduction technology utilizing nylon functionalized with synthetic dyes (nylon affinity networks) to capture and remove bacteria from plasma. In the initial screening process, we spiked phosphate buffer solution (PBS) and human plasma (1 mL each) with 10 or 100 colony forming units (cfu) of either Escherichia coli or Staphylococcus epidermidis, exposed the suspensions to affinity networks and assessed the extent of bacterial reduction using agar plate cultures as the assay output. Nineteen synthetic dyes were tested. Among these, Alcian Blue exhibited the best performance with both bacterial strains in both PBS and plasma. Next, bacterial suspensions of approximately 1 and 2 cfu/mL in 10 and 50 mL, respectively, were treated with Alcian Blue affinity networks in three sequential capture steps. This procedure resulted in complete bacterial depletion, as demonstrated by the lack of bacterial growth in the remaining fraction. The viability of the captured bacteria was confirmed by plating the post-treatment affinity networks on agar. Alcian Blue affinity networks captured and sequestered a few plasma proteins identified by liquid chromatography tandem mass spectrometry. These findings support the potential applicability of nylon affinity networks to enhance transfusion safety, although additional investigations are needed. Full article

The aim of this work is to evaluate the effectiveness of antimicrobial photodynamic therapy (aPDT) against oral MDR (multi-drug-resistant) Candida spp. infections related to orthodontic treatment with palatal expanders through in vitro study. Methods: PDT protocol: Curcumin + H₂O₂ was used as a photosensitizer activated by a 460 nm diode LED lamp, with an 8 mm blunt tip for 2 min in each spot of interest. In vitro simulation: A palatal expander sterile device was inserted into a custom-designed orthodontic bioreactor, realized with 10 mL of Sabouraud dextrose broth plus 10% human saliva and infected with an MDR C. albicans clinical isolate CA95 strain to reproduce an oral palatal expander infection. After 48 h of incubation at 37 °C, the device was treated with the PDT protocol. Two samples before and 5 min after the PDT process were taken and used to contaminate a Petri dish with a Sabouraud field to evaluate Candida spp. CFUs (colony-forming units). Results: A nearly 99% reduction in C. albicans colonies in the palatal expander biofilm was found after PDT. Conclusion: The data showed the effectiveness of using aPDT to treat palatal infection; however, specific patient oral micro-environment reproduction (Ph values, salivary flow, mucosal adhesion of photosensitizer) must be further analyzed. Full article

Background: Unambiguous clinical interpretation of PCR results for urinary tract infections (UTIs) remains a challenge. Here we compare and correlate multiplex qPCR results (quantification cycle values) with traditional microbial culture results (colony forming units) for clinical samples. Methods: Serial dilutions [10⁸ to 10⁰ colony forming units (CFU)/mL] were performed on five Gram-negative and two Gram-positive UTI-causing bacterial pathogens. For each dilution, quantitative cultures on solid media to confirm CFU/mL values and a real-time PCR UTI panel employing a nanofluidic Open Array^TM platform producing quantification cycle (Cq) values were performed. Cq values were correlated with CFU/mL values, generating a semi-quantitative interpretive scale for clinical samples. The clinical utility of the scale was then assessed using PCR and culture data from 168 clinical urine samples. Results: For Gram-negative bacteria, Cq values of <23, 23 to 28, and >28 corresponded with ≥10⁵ CFU/mL, <10⁵ CFU/mL and negative cultures, respectively. For Gram-positive bacteria, Cq values of <26, 26 to 30, and >30 corresponded with ≥10⁵ CFU/mL, <10⁵ CFU/mL and negative cultures, respectively. Among 168 urine specimens (including 138 Gram-negative and 30 Gram-positive bacteria), there was 83.3% agreement (n = 140/168) and 16.6% non-agreement (n = 28/168) between culture CFU/mL and qPCR Cq. Gram-negative bacteria had higher agreement (87.6%, 121/138) than Gram-positive bacteria (63.3%, 19/30). Conclusions: This study demonstrates that qPCR Cq results can be directly correlated with traditional urine quantitative culture results and reliably identify the clinically relevant cutoff of 10⁵ CFU/mL for detected uropathogens. Full article

Wildfires can significantly alter soil physicochemical conditions and microbial communities in forest ecosystems. This study aimed to characterize the culturable soil fungal community and evaluate biological activity in Banco Totumo Bijibana, a protected dry tropical forest in Atlántico, Colombia, affected by a wildfire in 2014. Twenty soil samples were collected for microbiological (10 cm depth) and physicochemical (30 cm) analysis. Basal respiration was measured using Stotzky’s method, nitrogen mineralization via Rawls’ method, and fungal diversity through culture-based identification and colony-forming unit (CFU) counts. Diversity was assessed using Simpson, Shannon–Weaver, and ACE indices. The soils presented low organic matter (0.70%) and nitrogen content (0.035%), with reduced biological activity as indicated by basal respiration (0.12 kg C ha⁻¹ d⁻¹) and mineralized nitrogen (5.61 kg ha⁻¹). Four fungal morphotypes, likely from the genus Aspergillus, were identified. Simpson index indicated moderate dominance, while Shannon–Weaver values reflected low diversity. Correlation analysis showed Aspergillus-3 was positively associated with moisture, whereas Aspergillus-4 correlated negatively with pH and sand content. The species accumulation curve reached an asymptote, suggesting an adequate sampling effort. Although no control site was included, the findings provide a baseline characterization of post-fire soil microbial structure and function in a dry tropical ecosystem. Full article

Disruption of the intestinal epithelial barrier is a key driver of gut-derived inflammation in various disorders, yet strategies to preserve or restore barrier integrity remain limited. To address this, we evaluated a four-strain Bifidobacterium mixture—selected for complementary anti-inflammatory potency and industrial scalability—in lipopolysaccharide (LPS)-challenged RAW 264.7 macrophages and a Caco-2/THP-1 transwell co-culture model. Pretreatment with the probiotic blend reduced nitric oxide (NO) release in a dose-dependent manner by 25.9–48.3% and significantly down-regulated the pro-inflammatory markers in macrophages. In the co-culture system, the formulation decreased these markers, increased transepithelial electrical resistance (TEER) by up to 31% at 10⁵ colony-forming unit (CFU)/mL after 48 h, and preserved the membrane localization of tight junction (TJ) proteins. Adhesion to Caco-2 cells (≈ 6%) matched that of the benchmark probiotic Lacticaseibacillus rhamnosus GG, suggesting direct epithelial engagement. These in vitro findings demonstrate that this probiotic mixture can attenuate LPS-driven inflammation and reinforce epithelial architecture, providing a mechanistic basis for its further evaluation in animal models and clinical studies of intestinal inflammatory disorders. Full article

Background: Monolithic zirconia has attracted considerable interest in dentistry due to its favorable physical and mechanical properties, making it a promising alternative for crown fabrication. Nonetheless, a standardized finishing protocol for this material has yet to be established. Objective: This study aimed to evaluate the surface characteristics and in vitro biofilm formation of zirconia finished by either polishing or glazing. Methods: A total of 72 zirconia specimens were fabricated and divided into control, glazing, and polishing groups. Surface analysis included roughness, wettability, and surface free energy. Microbiological analysis included CFU (colony-forming units per mL) counts, microbial adhesion at 2, 4, 6, and 8 h, biofilm biovolume, and qualitative biofilm assessment via scanning electron microscopy (sEm). Results: The glazing group showed significantly greater roughness than the polishing (p = 0.006) and control (p = 0.016) groups, along with a lower contact angle (polishing—p = 0.002; control—p < 0.001) and higher surface energy (polishing—p = 0.005; control—p < 0.001). No significant differences were observed in CFU counts for the tested microorganisms (C. albicans, p = 0.158; L. casei, p = 0.610; S. mutans, p = 0.904). Regarding microbial adhesion, the polishing group showed a smaller biofilm-covered area compared to the control group for both total biofilm (p = 0.008) and viable biofilm (p = 0.005). no statistically significant difference was observed in biofilm biovolume (p = 0.082). Conclusions: These findings suggest that, despite the surface differences among the groups, biofilm formation was not significantly affected. Full article

This work presents the synthesis, characterization and evaluation of physicochemical and biological properties of two new aminoporphyrazine derivatives bearing magnesium(II) cations in their cores and peripheral pyrrolyl groups. The synthesis was carried out in several stages, using classical methods and the Microwave-Assisted Organic Synthesis (MAOS) approach. The obtained compounds were characterized using spectral techniques: UV-Vis spectrophotometry, mass spectrometry, ¹H and ¹³C NMR spectroscopy. The porphyrazine derivatives were tested for their electrochemical properties (CV and DPV), which revealed four redox processes, of which in compound 7 positive shifts of oxidation potentials were observed, resulting from the presence of free phenolic hydroxyl groups. In spectroelectrochemical measurements, changes in UV-Vis spectra associated with the formation of positive-charged states were noted. Photophysical studies revealed the presence of characteristic absorption Q and Soret bands, low fluorescence quantum yields and small Stokes shifts. The efficiency of singlet oxygen generation (Φ_Δ) was higher for compound 6 (up to 0.06), but compound 7, despite its lower efficiency (0.02), was distinguished by a better biological activity profile. Toxicity tests using the Aliivibrio fischeri bacteria indicated the lower toxicity of 7 compared to 6. The most promising result was the strong photodynamic activity of porphyrazine 7 against the Methicillin-resistant Stapylococcus aureus (MRSA) strain, leading to a more-than-5.6-log decrease in viable counts after the colony forming units (CFU) after light irradiation. Compound 6 did not show any significant antibacterial activity. The obtained data indicate that porphyrazine 7 is a promising candidate for applications in photodynamic therapy of bacterial infections. Full article

This study aimed to evaluate whether probiotic administration could protect against cognitive impairments in a scopolamine-induced cognitive impairment mice model. Male C57BL/6 mice (8 weeks of age) were injected with scopolamine hydrobromide to induce memory impairments. The experimental groups were additionally supplemented with 10⁹ colony-forming units (CFU)/day probiotics containing Lactobacillus helveticus CNU395 or L. paracasei CNU396. Behavioral test results and histopathological evaluations showed that the spatial memory ability and pathological tissue abnormalities of the mice in the CNU395 and CNU396 groups significantly improved compared with those in the disease group. CNU395 and CNU396 mitigated scopolamine-induced neuroinflammation by reducing the expression of pro-inflammatory cytokines (IL-6, IL-8, IL-10, and TNF-α) and the NLRP3 inflammasome, through the inhibition of MAPK and NF-κB inflammatory pathways. Additionally, the CNU395 and CNU396 groups showed decreased levels of Iba-1 and Bax, alongside increased levels of BDNF and Bcl-2, relative to the disease group. Therefore, CNU395 or CNU396 supplementation might help prevent the onset of cognitive deficits and neuroinflammation. Full article

Beyond its immunological role, colostrum has emerged as a promising, non-invasive source of bioactive factors, including mesenchymal stem/stromal cells (MSCs). This study represents the first attempt to isolate and characterize MSCs from equine colostrum (C-MSCs) to assess their potential use in veterinary regenerative medicine. Colostrum (n = 6) was collected from mares immediately after their delivery and centrifuged, and the recovered cells were cultured under standard conditions. The C-MSCs displayed plastic adherence and a heterogeneous morphology, including spindle-shaped and epithelial-like cells. The population doubling time (PDT) values varied among the samples, and four out of six showed rapid proliferation (<2 days). Colony-forming unit (CFU) assays confirmed their clonogenic potential, though significant inter-sample variability was observed (p < 0.05). Spheroid formation assays revealed differences in cell–cell adhesion: four out of six samples formed stable spheroids within four days. A migration assay showed significant variability (p < 0.05): one out of six achieved complete wound closure within 72 h, whereas five out of six reached ~30% at 96 h. All samples were positive for adipogenic, chondrogenic, and osteogenic differentiation as shown via staining. RT-PCR confirmed MSC marker expression, while hematopoietic markers were absent. MHC-I expression was weak in five out of six samples, whereas MHC-II was consistently negative. These findings support equine colostrum as a viable MSC source, though its variability requires further validation with larger samples. Additional research is needed to investigate C-MSCs’ immunomodulatory properties and therapeutic potential. Full article

Continued efforts have been made to enhance the antibacterial properties of root canal sealers by adding antimicrobial agents to them. This study aims to investigate the antibacterial effect of 0.15% silver nanoparticles (NAg) and 5% dimethylaminohexadecyl methacrylate (DMAHDM) when added to EndoSequence Bioceramic (BC) sealer against Enterococcus faecalis (E. faecalis) biofilm and their impact on its physical properties (flowability and film thickness). Four root canal sealers were tested for flow and film thickness properties, as well as against antibiofilm of E. faecalis-impregnated dentin discs, as follows: group 1: EndoSequence BC sealer only; group 2: EndoSequence BC sealer + 0.15% NAg; group 3: EndoSequence BC sealer + 5% DMAHDM; and group 4: EndoSequence BC sealer + 0.15% NAg + 5% DMAHDM. The findings show that all groups had flow and film thickness values that were in accordance with the ISO requirements. Combining 0.15% NAg and 5% DMAHDM in EndoSequence significantly reduced colony-forming unit (CFU) counts by approximately 5 logs. The combination of NAg and DMAHDM offers a promising strategy for developing endodontic sealers with improved antimicrobial properties and acceptable physical performance. Full article

Clubroot, caused by Plasmodiophora brassicae Woronin, poses a major threat to Chinese cabbage (Brassica rapa subsp. pekinensis) production worldwide, significantly impacting crop yield, quality, and economic value. Biological control represents a promising approach since it is non-toxic and eco-friendly, and it reduces the risk of pathogen resistance development. In this study, our objective was to screen for actinomycetes that can effectively inhibit clubroot. We screened 13 actinomycete strains, identifying 2, XDS3-6 and CD1-1, with substantial in vivo inhibitory effects, achieving infection suppression rates above 64% against P. brassicae. Phylogenetic analysis classified XDS3-6 and CD1-1 as Streptomyces virginiae and Streptomyces cinnamonensis, respectively. Both strains exhibited protease and glucanase production capabilities, essential for pathogenic suppression. Additionally, these strains induced host defense responses, as evidenced by increased jasmonic acid (JA) and salicylic acid (SA) accumulation and elevated activities of defense-related enzymes. Colonization studies of XDS3-6 and CD1-1 mutant strains in cabbage roots indicated sustained root colonization, with peak colony-forming units (CFUs) at 20 days post-inoculation, reaching 11.0 × 10⁴ CFU/g and 8.5 × 10⁴ CFU/g, respectively, and persisting for at least 30 days. Overall, these findings underscore the potential of Streptomyces strains XDS3-6 and CD1-1 as effective biocontrol agents, providing a theoretical foundation for their application in managing clubroot in Chinese cabbage. Full article

Apple pomace, a by-product from the production of concentrated juice, is a major contributor to global food waste. Despite its beneficial nutritional profile, apple pomace is predominantly disposed of in landfills. Rapid fermentation and spoilage caused by microorganisms are compounding factors in this demise, despite significant research into upcycling strategies. Thus, there is an unmet need for economical approaches that allow for the preservation of pomace during storage and transportation to centralized processing facilities from regional hubs. To address this challenge, we investigated the potential of different preservatives for preventing microbial growth and the spoilage of apple pomace, including antimicrobials (natamycin and iodine), polysaccharides (chitosan and fucoidan), and acetic acid. Spread plates for total microbial and fungal counts were employed to assess the effectiveness of the treatments. High concentrations (10,000 ppm) of chitosan were effective at reducing the microbial load and inhibiting growth, and in combination with antimicrobials, eliminated all microbes below detectable levels. Nevertheless, acetic acid at an equivalent concentration to commercial vinegar displayed the highest economic potential. Apple pomace submerged in 0.8 M acetic acid (3 kg pomace per liter) resulted in a five-log reduction in the microbial colony-forming units (CFUs) out to 14 days and prevented fermentation and ethanol production. These results provide a foundation for the short-term storage and preservation of apple pomace that could contribute to its upcycling. Full article

The detection of colony-forming units (CFUs) is a time-consuming but essential task in mulberry bacterial blight research. To overcome the problem of inaccurate small-target detection and high computational consumption in mulberry bacterial blight colony detection task, a mulberry bacterial blight colony dataset (MBCD) consisting of 310 images and 23,524 colonies is presented. Based on the MBCD, a colony detection model named Colony-YOLO is proposed. Firstly, the lightweight backbone network StarNet is employed, aiming to enhance feature extraction capabilities while reducing computational complexity. Next, C2f-MLCA is designed by embedding MLCA (Mixed Local Channel Attention) into the C2f module of YOLOv8 to integrate local and global feature information, thereby enhancing feature representation capabilities. Furthermore, the Shape-IoU loss function is implemented to prioritize geometric consistency between predicted and ground truth bounding boxes. Experiment results show that the Colony-YOLO achieved an mAP of 96.1% on MBCDs, which is 4.8% higher than the baseline YOLOv8n, with FLOPs and Params reduced by 1.8 G and 0.8 M, respectively. Comprehensive evaluations demonstrate that our method excels in detection accuracy while maintaining lower complexity, making it effective for colony detection in practical applications. Full article

Surgical Site Infection (SSI) can be a devastating complication, leading to increased morbidity, mortality, and healthcare costs. Pre-surgical hand preparation is an effective strategy to prevent SSI. The two most common pre-surgical hand preparation methods are antimicrobial soap for surgical hand scrub and alcohol-based surgical hand rub. The antimicrobial soap hand scrub remains more commonly used among operating theater staff. However, several studies showed that alcohol-based hand rubs are much more effective than antiseptic soap hand scrubs. Objective: This study aimed to compare the effect of the two methods of surgical hand preparation on the number of bacterial colonies. Methods: The design of this study was a comparative study with a pre-test and post-test approach in two groups (a surgical hand scrub using 4% chlorhexidine soap group and a surgical hand rub using 70% ethyl alcohol and 2.5% chlorhexidine group). Hand smear sampling was performed before surgical hand preparation (pre-test), immediately after surgical hand preparation (post-test 1), and after the surgery was completed (post-test 2). Seventy-one hand smear samples (35 samples applied the surgical hand rub, and 36 samples applied the surgical hand scrub) were divided into two groups and examined for colony counts in Colony Forming Units (CFU) using the total plate count method. Descriptive and comparative analysis were applied. Results: The surgical hand-scrub group had average pre-test, post-test 1, and post-test 2 colony counts of 0.202 CFU/cm², 0.007 CFU/cm², and 0.016 CFU/cm², respectively, while the surgical hand-rub group had average pre-test, post-test 1, and post-test 2 colony counts of 0.163 CFU/cm², 0.001 CFU/cm², and 0.001 CFU/cm² respectively. Statistical analysis using the Friedman test showed that both methods significantly reduced the number of colonies (p < 0.01). Based on the Mann–Whitney test, there was no significant difference between the two groups regarding the number of colonies (p > 0.05). Conclusions: Surgical hand-scrub and hand-rub have similar effectiveness in reducing and maintaining the number of colonies on hands during surgery, both gram-positive and gram-negative bacteria. Full article

Background/Objectives: Natural products such as honey and propolis have been widely studied for their antimicrobial properties. Combining these substances has shown synergistic effects against foodborne pathogens and has also demonstrated promising results in previous applications on fermented meat products. This study evaluated the antibacterial potential of Spanish thyme (Thymus spp.) and chestnut (Castanea sativa) honeys, enriched with 10% ethanolic extract of propolis, against two major foodborne pathogens: Listeria monocytogenes and Clostridium perfringens. Methods: Antibacterial activity was assessed using broth microdilution assays and colony-forming unit (CFU) counts. The phenolic composition of the most active samples was characterized by LC-MS-Q/TOF and UPLC-PDA to identify and quantify the bioactive compounds. Results: All samples exhibited differential responses depending on the pathogen, with C. perfringens being the most susceptible. Propolis addition significantly enhanced the bactericidal response of honey against L. monocytogenes and C. perfringens (p < 0.05). This effect correlated with higher levels of antimicrobial phenolic compounds, particularly cinnamic acid derivatives, pinobanksin-3-O-hexanoside, sakuranetin, quercetin, and quercetin-3,7-dimethyl ether. Conclusions: These findings support the synergistic antibacterial potential of honey-propolis combinations, highlighting their application as natural preservatives for reducing the risk of foodborne diseases, as well as bioactive ingredients in nutraceutical formulations with antibacterial properties and additional health benefits. Full article