Microbial Tests Research Articles

Validation of the Peel Plate Staphylococcus Aureus (SA) Test for Enumeration of S. aureus in Selected Foods and Non-cultured Dairy Products: AOAC Performance Tested MethodSM 082401.

The microbial testing platform, Peel Plate™, was developed with Baird Parker ingredients for Staphylococcus aureus (SA) specificity. After rehydrating with 1 mL of the diluted food sample, Peel Plate SA is incubated for 24-48 h at 35-37 °C and observed for purple colonies. A validation study was performed to evaluate Peel Plate SA for enumeration of S. aureus in selected foods and non-cultured dairy products for Performance Tested MethodsSM (PTM) certification. Peel Plate SA was evaluated in inclusivity/exclusivity and matrix studies, product consistency, stability, and robustness testing. Non-fat dried milk, frozen raw cod fish, corned beef, frozen raw vegetables, potato salad, vegetable soup, frozen unshelled raw shrimp and baby food (apple, cinnamon, and granola) were evaluated in the matrix studies comparing Peel Plate SA to U.S. and international reference methods. Three levels of contamination along with non-inoculated controls were tested for each matrix. Peel Plate SA detected 49 of 50 S. aureus isolates tested. Of the 38 exclusivity species tested, none were detected. In the matrix studies, the Peel Plate SA results were determined to be equivalent to the reference method results by paired statistical analysis. In an accelerated stability study, the shelf-life of Peel Plate SA was shown to be stable for 12 months. Equivalence was demonstrated between different production lots. Small changes to critical test parameters did not significantly affect the Peel Plate SA results. Peel Plate SA is a ready-to-use method for enumeration of S. aureus in a variety of foods and non-cultured dairy products. As with reference methods, colonies Peel Plate SA colonies should be isolated and confirmed with differentiation tests such as catalase and strong coagulase positive. The data were reviewed by the PTM Program and certification was granted for the Peel Plate SA method PTM 082401.

Bio-inhibitive corrosion effect of carica papaya leaf extract on cold-rolled mild steel in 0.1 M HCl solution

Plant extracts are prone to microbial growth that can lead to microbial-induced corrosion (MIC), a major setback for their performance and stability as corrosion inhibitors. Hence, this work aims to identify the microbes that may cause the ineffectiveness of carica papaya leaf extract (CPLE) as a bio-corrosion inhibitor of cold-rolled mild steel in 0.1 M HCl solution for 48 days at 28℃. Cold-rolled mild steel coupons were immersed in 100 ml of 0.1 M hydrochloric (HCl) acid solution containing 1 g, 2 g, 3 g, 4 g, and 5 g of carica papaya leaf extract (CPLE) for 48 days at 28℃. The gravimetric method was used to determine the coupons' corrosion rate (CR), surface coverage, and inhibition efficiency (IE%) of the CPLE. The functional groups in the CPLE were identified using Fourier Transform Infrared Spectroscopy (FTIR), and the surface appearance of the coupons after immersion was examined using an atomic force microscope (AFM). Gravimetric data showed the coupons dipped in a 0.1 M HCl solution containing 3 g/100 ml of the inhibitor exhibited the highest inhibition efficiency of 87.73%, surface coverage of 0.88, and lowest corrosion rate of 0.00255 mm/day or 0.93 mm/yr, after 48 days at 28℃. In FTIR, transmittance peaks occurred at 1558 cm−1 for amines (-NH) in alkaloid scissoring, 1452 cm−1 for aromatic -C = C in flavonoids, 2932 cm−1 for aliphatic methylene (-CH2) and aldehyde (RCOH) stretching, 1035 and 1077 cm−1 for aromatic-OR in tannin, and 3280 cm−1 for out-of-plane bending of hydroxyl (-OH) in phenolics. Vitamin C (522,940 μg/g), flavonoids (860 μg/g), saponins (637.9 μg/g), terpenoid (48.4 μg/g), phenol (120%μg/g), alkaloid (4.18 μg/g), tannin (59.84%), and glycosides (9.04%) make up the extract's average phytochemical content. AFM presents pits and ridges on the mild steel coupons immersed in 0.1 M HCl solution without the extract. Those immersed in the solutions with varying concentrations of the extract had a passive layer of the CPLE adhering to the surfaces of the coupons thereby preventing the coupon’s direct contact with the acid solution and weight loss. However, over time, microbial growth decreased the efficiency of CPLE due to metabolites. Microbial tests show creamy, irregular and raised bacterial total colony-forming units per gram (Tcfu/g) as 4.6 × 105 Tcfu/g and 1.9 × 107 Tcfu/g in 2 runs. Also, a mixture of white and fluffy appearance and spore formation of fungi population of 4.8 × 105 Tcfu/g and 3.2 × 107 Tcfu/g in 2 Runs made up of Penicillium spp, Coccidioides immitis, Aspergillus flavus, and Fusarium spp, with hyphae, were seen in the solutions containing CPLE.

Antimicrobial Effect of Zinc Oxide Nanoparticle Coating on Titanium 6 Aluminum 4 Vanadium (Ti-6Al-4V)-Fixed Orthodontic Retainer Substrate

Abstract Objectives Due to its excellent biocompatibility, superior mechanical qualities, and exceptional corrosion resistance, titanium 6 aluminum 4 vanadium (Ti-6Al-4V) alloy is frequently used for medical and orthodontic purposes as a fixed retainer after active orthodontic treatment. Titanium lacks the antibacterial characteristics and is bioinert, this may influence the usage of such materials in the field of biomedical applications. Bacterial adhesion to the orthodontic retainer surface is a common first step in infection; this is followed by bacterial colonization ending with the formation of a biofilm. Once biofilm forms, it is highly resistant to medicines and the host immune system's defense mechanism, making it difficult to remove the biofilm from orthodontic retainer. This study aimed to test the antimicrobial effect of a zinc oxide (ZnO) nanoparticle coating on Ti-6Al-4V orthodontic retainers. Materials and Methods ZnO nanoparticles, with a particle size of 10 to 30 nm, were used to coat the alloy using the electrophoretic deposition method. Various parameters and surface characterization tests were employed to obtain an optimized sample. This sample was subjected to the microbial adherence optical density test to examine the adherence of Streptococcus mutans, Lactobacillus acidophilus bacteria, and Candida albicans. Results The optimized sample had a 5-mg/L ZnO concentration, applied voltage of 50 V, and a 1-cm distance between electrodes. The ZnO coating significantly reduced microbial adherence compared to uncoated samples, effectively inhibiting bacterial development. Conclusion Electrophoretic deposition is an efficient and cost-effective technique for coating orthodontic titanium retainer substrates. Coating Ti-6Al-4V with ZnO nanoparticles increased the antimicrobial effectiveness of the material and as the concentration of the nanoparticles rises, the antimicrobial effect increases too.

The Description of Microbial Pattern and Antibiotic Sensitivity Among Pediatric Patients at RSUP M Djamil Padang

Background Infection alludes to the invasion and multiplication of either microorganisms or parasites inside bodily tissues. The management of such infections is closely interrelated to the use of antibiotics. Ineffective use of antibiotics is contributed to the antibiotic resistance. Severe disease complications and lengthy hospital stays are among essential reasons why physicians may prescribe myriad types of antibiotics for longer durations. In effort to diminish resistance, the selection of antibiotics ought to be based on information about the bacterial spectrum causing the infection and the patterns of sensitivity to antibiotics. Annual reporting of microbial patterns and sensitivity testing is essential, particularly for pediatric ward patients, as it provides a guide for administering relevant antibiotics and preventing further spread of infections. Objectives This study evaluated microbial patterns, sensitivity test results, and antibiotic resistance among patients in the pediatric ward of RSUP M Djamil Padang from January-December 2020, with a total of 138 samples. Results The proportion of gram-negative and gram-positive bacteria are 83.3% and 16.7%, respectively. The most prevalent gram-negative bacteria are Klebsiella pneumoniae (28.9%), Escherichia coli (26.1%). Pseudomonas aeruginosa (7.9%), Staphylococcus epidermidis (7.2%) and Acinetobacter baumannii (3.7%) also present. These bacteria are predominantly found in samples of feces, urine, and blood. Gram-positive bacteria show notable resistance to the antibiotics such as erythromycin (22.2%), trimethoprim-sulfamethoxazole (19%), and ciprofloxacin (15.8%), while being sensitive to chloramphenicol (17.4%), vancomycin (15.1%), and tetracycline (12%). In contrast, gram-negative bacteria exhibit resistance to ampicillin (16.5%), ceftriaxone (12.1%), and ceftazidime (11.3%), but are sensitive to amikacin (19.8%), meropenem (19.4%), and gentamicin (10.9%). Keywords: microbial patterns, antibiotic sensitivity, pediatric ward

Freeze-dried wafers containing sesame oil for alleviation of dry mouth

A dry mouth is a condition with significant morbidity. Conventional saliva substitutes are expensive, short-lived, and prone to contamination. This study presents a Freeze-Dried Sesame Oil Emulsion Saliva Substitute (FD-SOESS), which combines the advantages of sesame oil through a freeze-drying process and assesses its effectiveness. High-speed homogenization (HSH) as well as high-pressure homogenization (HPH) techniques were employed to fabricate the FD-SOESS. The formulations that underwent the additional HPH step demonstrated improved physical properties, such as lower viscosity and faster redispersion times, compared to HSH alone. The optimized formulation (F11) possessed a near neutral pH of 6.67 and rapid re-dispersibility that was <141.5 s), which is acceptable for oral administration. Additionally, the FD-SOESS formulation revealed heterogeneous porous structures with a layered arrangement of different pore sizes, and the resulting formulation had low moisture content (2.76 %). The formulation met the microbial limit test. The antioxidant IC₅₀ of sesamin was found to be 0.318 μM. Furthermore, it was not toxic to periodontal cells at 50 μg/mL or 100 μg/mL. Human periodontal cell lines subjected to scratch and treated with FD-SOESS demonstrated notable migration that achieved complete wound closure within two days. The administration of FD-SOESS led to a notable elevation in the mucus concentrations found in the saliva samples of all participants. Overall, the results indicated that FD-SOESS is a highly promising alternative to saliva and may improve oral health for individuals suffering from dry mouth.

Improvement of thermostable productivity ?-amylase from local isolate Bacillus licheniformis H14.

(28)Bacterial local isolates of Bacillus sp. were obtained from soil samples. Isolates were tested for thermostable alpha- amylase production on solid media; fifteen isolates were able to develop clear zone around the bacterial growth after floating the plates with iodine reagent (Lugol's solution). There were further tested in submerged culture which led to selection of Bacillus sp. H14since it was the most efficient .Microbial and biochemical tests showed that the local isolate Bacillus sp.H14was refered to the species B.licheniformis that signed as H14 was refered to the species B.licheniformis H14 .,To get ahigher yield of alpha – amylase(48.70unit/mg protein) production from the local isolate B.licheniformis H14 . This study used different mutation ways such as physical way by using the physical mutagen (ultraviolet light) and chemical way by using the chemical mutagen (nitrosoguanidine). Physical mutation results showed that the local isolate B.licheniformis HM14 get higher yield of alpha – amylase production(102.10 unit/mg protein) according to killing percentage (90%) while the chemical mutation results showed that the local isolate B.licheniformis HM4 get higher yield of alpha –amylase production(100.94 unit/mg protein) from the two mutant local isolates (HM14 and HM4)were the best carbon source starch (1.5%), peptone (1.5%) as nitrogen source, calcium chloride (0.02%), sodium chloride (0.05%), magnicium phosphate (0.05%), sodium di –hydrogen phosphate (0.16%), at initial pH (5) and inoculum size 1*108 cfu/ml at (50?C) For (72) hours, using shaking incubator at (150) rpm.

Structural characteristics and biological evaluation of copper coating cotton material obtained by chemical reduction method

The article describes the preparation of new cotton materials obtained by chemical deposition of copper sulfide. This two-stage process consists of chelation of copper sulfate on cellulose chains of cotton (COT → COT-CuSO4) with subsequent precipitation of copper in the form of copper sulfide (COT-CuSO4 → COT-CuS) using sodium sulfide. The obtained COT-CuS composites were characterized physicobiologically. Thus, the structural characteristic of the Cotton-CuS material was determined by microscopy analysis (SEM), Atomic Absorption Spectrometry with Flame Excitation (FAAS), specific surface area and total pore volume analysis (BET). The copper functionalized cotton fabric was subjected to microbial activity tests against colonies of Gram-negative (Escherichia coli) and Gram-positive ( Staphylococcus aureus) bacteria and Chaetomium globosum, Aspergillus niger fungal molds species. Biochemical evaluation includes hematological tests of activated partial thromboplastin time (aPTT) and prothrombin time (PT). The substantial antimicrobial properties of the newly synthesized COT-CuS material with the lack of influence on blood coagulation processes offer prospects of a potential use as applications as an antibacterial/antifungal material.

Production and Evaluation of Peanut Butter Prepared with Peanut Shells

Background:: Innovative application of processing is an emerging trend in food production. Objective:: The present study was conducted to produce peanut butter and evaluate the physical, chemical, and sensory properties of the product, to which the outer shells of peanuts were added in different proportions (5, 10, 15%) to reduce the calories of the product by reducing the fat content in the peanut butter as well as benefiting from the shells as a residue secondary to the peanut seeds. Methods:: The chemical composition of the prepared sample, along with bioactive determination Using HPLC, microbial testing, Aflatoxin content, and sensory evaluation, have been done for the prepared peanut butter using standard methods. Results:: The chemical composition of the peanut outer shell powder was characterized by the highest value of fiber (46.6%), followed by total carbohydrates and protein (23.25%, (12.54%) respectively. The produced peanut butter showed that the total carbohydrate resulted in the highest value (23.25%), followed by fat (42.21) and protein (28.12%). Substitution at 5, 10, and 15% peanut outer shell resulted in a non-significant difference concerning protein. At the same time, the lipid content showed a significant decrease compared to the control. A similar trend was found concerning total carbohydrate-to-fat content. Total fiber increased to 1.5 &amp; 2.08, and 2.6 times as high as the content parallel to dietary fiber, while β-Carotene decreased significantly due to the substitution level. The substitution level decreased energy (cal) by about 203.58, 730.093, 562.86, 545.19, and 526.66, respectively, compared with the control. A slight increase was found in the mineral content due to the substitution, except for the calcium increases at 15%. DPPH and ABTS% increased in parallel with the substitution level, which was in line with total phenols and flavonoids. Flavonoid fraction resulted in nariagin (94.72 QE), the major flavonoid, followed by lutein (82.23 QE). Meanwhile, phenolic compounds were described with pyrogallol (68.31 GAE) (as the main compound, followed by chlorogenic (780.76 GAE). The fatty acid composition showed that oleic and linoleic were predominant in all treatments. Bacterial, yeast, and mold counts appeared after three months of storage (20 ± 2°C). Aflatoxin was not detectable in the sample of the peanut outer shells and peanut butter samples. Sensory characteristics showed approximately the same score for all treatments except that of 15% substitution, which resulted in a significant decrease in all parameters compared with the control. Conclusion:: This study reported that 5%, followed by 10% of peanut outer shells, were the most suitable levels for making peanut butter, improving the nutritional value by increasing the percentage of fiber and antioxidants in peanut shells, leading to better quality products and shelf life.

Campylobacteriosis Outbreak Linked to Municipal Water, Nebraska, USA, 20211.

In September 2021, eight campylobacteriosis cases were identified in a town in Nebraska, USA. We assessed potential exposures for a case-control analysis. We conducted whole-genome sequencing on Campylobacter isolates from patients' stool specimens. We collected large-volume dead-end ultrafiltration water samples for Campylobacter and microbial source tracking testing at the Centers for Disease Control and Prevention. We identified 64 cases in 2 waves of illnesses. Untreated municipal tap water consumption was strongly associated with illness (wave 1 odds ratio 15.36; wave 2 odds ratio 16.11). Whole-genome sequencing of 12 isolates identified 2 distinct Campylobacter jejuni subtypes (1 subtype/wave). The town began water chlorination, after which water testing detected coliforms. One dead-end ultrafiltration sample yielded nonculturable Campylobacter and avian-specific fecal rRNA genomic material. Our investigation implicated contaminated, untreated, municipal water as the source. Results of microbial source tracking supported mitigation with continued water chlorination. No further campylobacteriosis cases attributable to water were reported.

Development of a flexible produce supply chain food safety risk model: Comparing tradeoffs between improved process controls and additional product testing for leafy greens as a test case.

The produce industry needs a tool to evaluate food safety interventions and prioritize investments and future research. A model was developedin R for a generic produce supply chain and made accessible via Shiny. Microbial contamination events, increases, reductions, and testing can be modeled. The output for each lot was the risk of one, 300-gram sample testing positive, described by two industry-relevant risk metrics, the overall risk of a positive test (proxy for recall risk) and the number of lots with the highest risk (>1 in 10 chance) of testing positive (proxy for public health risk). A leafy green supply chain contaminated with Shiga-toxin-producing Escherichia coli was modeled with a mean of 1 pathogen cell per pound (µ=1 CFU/lb or -2.65 Log(CFU/g)) under high (σ=0.8 Log(CFU/g)) and low (σ=0.2 Log(CFU/g)) variability. Baseline risk of a positive test in the low-variability scenario (1 in 20,000) was lower than for high-variability (1 in 4,500), showing rare high-level contamination drives risk. To evaluate tradeoffs, we modeled two well-studied, frequently used interventions: additional product testing (8 of 375-gram tests/lot) and improved process controls (additional -0.87±0.32 Log(CFU/g) reduction). Improved process controls better reduced recall risk (to 1 in 115,000 and 1 in 26,000 for low- and high-variability, respectively), compared to additional product testing (to 1 in 21,000 and 1 in 11,000 for low- and high-variability, respectively). For low variability contamination, no highest risk lots existed. Under high variability contamination, both interventions removed all highest risk lots (about 0.05% of total). Yet, additional product testing rejected more lower-risk lots (about 1% of total), suggesting meaningful food waste tradeoffs. This model evaluates tradeoffs between interventions using industry-relevant risk metrics to support decision-making and can be adapted to assess other commodities, process stages, and less-studied interventions.

Screening methods for antibiotic residue detection in milk: Recent advances, challenges, and regulations

Antimicrobial residues in milk pose a significant risk to human health, prompting regulatory bodies to establish safety limits to protect consumers. While traditional screening methods have primarily targeted single analytes or classes, recent advancements in multiclass screening techniques offer more comprehensive and efficient monitoring. This review highlights these advancements and focuses on methods developed since 2010, such as microbial inhibition tests, immunoassays, biosensors and LC–MS‐based approaches. It also discusses the strengths and limitations of these techniques, as well as the challenges associated with analysing milk's complex matrix, emphasising the ongoing need for innovation in food safety practices.

Toll-like Receptor Expression in Pelodiscus sinensis Reveals Differential Responses after Aeromonas hydrophila Infection.

Background: Toll-like receptor (TLR), as an important pattern recognition receptor, is a bridge between non-specific immunity and specific immunity, and plays a vital role in the disease resistance of aquatic animals. However, the function of TLR in Pelodiscus sinensis is still unclear. Methods and Results: The sequence characteristics and homology of three TLRs (PsTLR2, PsTLR3 and PsTLR5) were determined in this investigation. Their annotation and orthologies were supported by phylogenetic analysis, functional domain prediction, and sequence similarity analysis. qPCR showed that the identified TLRs were expressed in all tissues, among the high expression of PsTLR5 in the brain and liver and the high expression of PsTLR2 and PsTLR3 in the liver. PsTLR2 mRNA expression increased 6.7-fold in the liver 12 h after Aeromonas hydrophila infection, while the mRNA expression of PsTLR3 was down-regulated by 0.29 times in liver and 0.31 times in spleen. The mRNA expression of PsTLR5 was significantly up-regulated in four immune tissues, and it was up-regulated by 122.8 times in the spleen after 72 h infection. Finally, the recombinant proteins of extracellular LRR domains of these three TLRs were obtained by prokaryotic expression technology, and the binding tests were performed to discover their ability of binding pathogenic microorganisms. Microbial binding test showed that rPsTLR2, rPsTLR3 and rPsTLR5 can combine A. hydrophila, Edwardsiella tarda, Vibrio parahaemolyticus, Staphylococcus aureus, Streptococcus agalactiae and Candida albicans, while rPsTLR3 can bind A. hydrophila, E. tarda, V. parahaemolyticus and C. albicans. Conclusions: Our findings suggested that TLRs may be crucial to turtles' innate immune response against microbes.

Three-dimensional gel network structure of agarose interlayer dispersed Pd nanoparticles in copper foam electrode for electrocatalytic degradation of doxycycline hydrochloride

In this study, we successfully prepared palladium/agarose/copper foam (Pd/AG/CF) composite electrodes by utilizing the three-dimensional network structure agarose (AG), a green material derived from biomass, and homogeneously immobilizing palladium (Pd) atoms on a copper foam (CF) substrate through a facile route. The electrode showed excellent performance in the electrocatalytic degradation of doxycycline (DOX), with a high DOX degradation rate of 92.19 % in 60 min. In-depth studies revealed that palladium can form metal-metal interactions with the CF substrates, which enhances the electron transfer on the catalyst surface. In addition, the introduction of agarose effectively prevented the agglomeration of palladium nanoparticles. In addition, the hydroxyl functional groups in the molecular structure of agarose facilitate interactions between water molecules and the electrode interface through the formation of hydrogen bonds, thereby further enhancing the efficiency of the electrocatalytic reaction. In addition to good stability and reusability. Microbial toxicity test results show that the degraded wastewater has minimal impact on the environment. Also, possible degradation pathways of DOX were explored in this study. Finally, a novel continuous flow reactor was designed, featuring a unique design that ensures full contact between wastewater and the composite electrodes, thereby achieving continuous and efficient treatment of antibiotic wastewater.

Physicochemical Properties, Heavy Metal and Pesticide Contaminations, and Microbial Limit Tests of Cannabis Oral Drops

Cannabis, a medicinal herb renowned for its therapeutic potential, is utilized in the treatment of various ailments, including the stimulation of appetite in cancer patients. In Thailand, the predominant dosage form is oral drops; however, the absence of robust quality control measures for these products poses significant health risks to patients. The primary objectives of this study were to formulate and evaluate cannabis oral drops, with a comprehensive evaluation encompassing physicochemical properties such as appearance, pH, Δ9-tetrahydrocannabinol, and cannabidiol contents. Furthermore, heavy metals (specifically arsenic, cadmium, and lead), pesticides (including pyrethroids, organochlorines, organophosphates, and carbamates), and microbial contaminations (Staphylococcus aureus, Clostridium spp., and Salmonella spp.) were evaluated. The results revealed that the optimal formulation, comprising cannabis extract derived from supercritical carbon dioxide fluid, vitamin E acetate, and medium-chain triglyceride oil, exhibited a pH of approximately 4.0, a Δ9-tetrahydrocannabinol content of approximately 27 mg/mL, and a cannabidiol content of approximately 9 mg/mL. Furthermore, there were no heavy metals or pesticides detected. Microbial limit tests demonstrated the absence of Staphylococcus aureus, Clostridium spp., and Salmonella spp. In conclusion, this endeavor successfully achieved the development of high-quality cannabis oral drops, showcasing the potential for safe and therapeutic use.

The application of copper sulfate mixed with Caesalpinia sappan L. extract to increase colorfastness in pressed blush products

This study aims to increase the colorfastness of pressed blush products by combining copper sulfate with Caesalpinia sappan L. extract. This experiment consisted of four conditions used for color extraction: 70% w w-1, 95% w w-1, 70% w w-1 with 10% w w-1 copper sulfate, and 95% w w-1 with 10% w w-1 copper sulfate. The highest yield percentage of crude extract was found at 70% w w-1, with the highest absorption value (λmax) at 70% methanol with 10% w w-1 copper sulfate. The darkest shade of red was found at 70% w w-1 with 10% w w-1 copper sulfate. The development of pressed blush occurred when corn starch was mixed with more white color and smell than arrowroot flour. The highest red color was achieved at 4.5% w w-1, with the highest red - purple intensity. The microbial contamination test showed no microbial contamination in pressed blush products. GRAPHICAL ABSTRACT HIGHLIGHTS Caesalpinia sappan L. was extracted using maceration methods with methanol solvent. Phytochemical screening revealed pink anthraquinone and anthocyanidins. The chemical properties showed a pH range of 5.31–5.74, maximum light absorption, and mordant increased absorption. A compress blush was developed with corn starch and arrowroot flour, suitable for the cosmetic industry.

Bugs and Brains: The Microbiome &amp; Dementia

Interest in the microbiome and its correlation with different neurological diseases has grown significantly over the past decade. The gut microbiome contains a vast array of diverse organisms living in the gastrointestinal (GI) tract. Predominantly composed of bacteria, the gut microbiome helps regulate homeostasis and metabolism in the host, aiding in immune system development as well as vitamin and nutrient absorption. Studies suggest that, in addition to providing humans with these physiological benefits, the gut microbiome is also linked to and communicates with the brain via the gut-brain axis (GBA). Long-standing research on the GBA has demonstrated that the GI tract and the central nervous system are interconnected through both neurological and immunological signaling pathways. Recent research is expanding our understanding of the microbiome and the GBA, revealing correlations between the microbiome impact on the GBA and neurological conditions such as Alzheimer’s dementia and Lewy body dementia, going as far as to identify and highlight specific microbial species that may serve as risk or protective factors for various forms of dementia. This letter aims to highlight the current findings and recommend the use of tools such as microbial cell-free DNA testing to gain a better understanding of the role of gut dysbiosis in dementia patients.

Antimicrobial stewardship and education in optometry

ABSTRACT Clinical relevance Antimicrobial stewardship aims to improve how antibiotics are prescribed by clinicians and used by patients, to ensure safe appropriate use, and to prevent and contain antimicrobial resistance. Background Australian optometrists can prescribe a range of antimicrobial agents, but to what extent they consider antimicrobial stewardship is not known. This study evaluated what final-year optometry students and optometrists understood about antimicrobial stewardship in eye care and considered relevance to oral prescribing and education. Methods A knowledge, attitude, and practice (KAP) questionnaire was developed comprising four sections: i) demographic questions, ii) 10 multiple choice questions regarding Knowledge about antimicrobial agents and likely pathogens, diagnosis, treatment, and preventing resistance, iii) 10 Likert rating scale questions about thoughts and Attitudes, iv) mix of question types (5× MCQ: course of action, 16 Likert scale: confidence) related to Practice (diagnosis, management, and prescribing). Descriptive analyses were conducted (medians, mean±SD, and distributions). Results Thirteen students and 36 optometrists completed the survey. Both groups had a good understanding of microbial resistance and antibiotic prescribing for ocular conditions; average knowledge scores were 9.2 ± 0.7 and 8.7 ± 1.1 for students and practitioners, respectively. Scores were neutral to agree for questions related to the need for more educational programs. The answers of practice-related MCQs had a dichotomy of answers indicating a diversity of opinion, as can be the case in practice. Average total practice confidence scores were approximately 57/80 for students and 68/80 for optometrists. Optometrists and students were very confident in their ability to conduct an appropriate case history and use their knowledge and clinical skills, including slit lamp anterior eye assessment. The lowest confidence scores were for conducting microbial testing, i.e. taking swabs for pathology. Conclusion Student and optometrist knowledge, attitudes, and practice around antimicrobial stewardship were high and in line with other health professions globally. There is scope for increased stewardship training.

Evaluation of Gentamicin Release of PMMA Cements Using Different Methods: HPLC, Elution and Inhibition Zone Testing.

(1) Background: There is an ongoing discussion on the elution efficacy of antibiotic-impregnated cements. Our experiments were intended to clarify if there are differences in the antibiotic elution of HPLC compared with inhibition zone testing using eluates or PMMA discs. (2) Materials and Methods: Two cement brands with different concentrations of the active ingredient were tested in antimicrobial Kirby-Bauer (disc diffusion) assays. Cement platelets were directly applied on the agar plates and their zone of inhibition was measured. In parallel, the platelets were incubated in phosphate buffered saline (PBS) and at distinct points of time transferred into new buffer. At these time points, 50 µL of the bone cement eluates was used for zone of inhibition testing. Standard gentamicin sulfate solutions served as a control in the same test setup. To verify the microbiological investigations, the antibiotic content of the eluates was also measured via high-performance liquid chromatography (HPLC). (3) Results: The experiments with cement eluates showed better differentiable results than the direct application of the cement discs. The results were also comparable to investigations with HPLC and gentamicin sulfate standard solutions. (4) Conclusions: The results of elution rates are influenced by the test system and the period of observation chosen. The microbial test systems reflect the results of HPLC to the same degree and give evidence of the efficacy of the antibiotics. The HPLC tests on eluates were more suitable in representing differences in release characteristics.

Feasibility, efficacy, and safety of animal-assisted activities with visiting dogs in inpatient pediatric oncology.

Childhood cancer entails a heavy burden for patients and their families. Recent advances in overall survival rates have increasingly brought long-term quality of life into focus. Animal-assisted activities (AAAs) have long been hypothesized to alleviate the burden on pediatric patients and their peers in the hospital setting. However, their use in inpatient pediatric oncology has been a sensitive issue mainly due to the fear of infections, resulting in a lack of studies. This study presents data on the feasibility, safety, and efficacy of AAAs from a single German center. Between 2018 and 2022, 60 patients (median age = 10.3years) diagnosed with malignancy and undergoing treatment were visited by an intervention dog (total visits = 100). Patients were screened for infections as per hospital policy, with additional microbiological testing performed based on symptoms. The dog was screened for human pathogens and zoonoses. Microbial data and hospitalizations were analyzed from twomonths prior to the first visit until twomonths after the last visit. Acceptance of being in the hospital, both with and without planned animal-assisted interventions and pre- and post-intervention state stress, were measured using a validated visual analogue scale (0-10). Patients benefited from AAAs, showing increased acceptance of being in the hospital (median: 7.25 vs. 4.50, P < 0.001) and decreased median state stress ratings one hour after the visit compared to one hour before the visit (1.00 vs. 4.25, P < 0.001). The intervention did not result in an increased number of infections or unplanned hospitalizations, and no zoonoses were detected. All microbial screening tests of the dog were negative. AAAs with visiting dogs in inpatient pediatric oncology are feasible and safe. Although they hold promise for enhancing patients' well-being, further prospective studies are needed. Supplementary file2 (MP4 240076KB).

Preparation, Quality control and Standardization of a Destructive Distillate &lt;i&gt;Swasakasa Nei&lt;/i&gt; (SKN), A Traditional Siddha Herbal Pharmaceutic for &lt;i&gt;Swasakasam&lt;/i&gt; (Bronchial Asthma)

Standardization is essential to ensure the quality and reliability of traditional medicines. This study aimed to collect, authenticate and purification of raw materials, preparation of &lt;i&gt;Swasakasa Nei&lt;/i&gt; (SKN) according to SOP, and Quality evaluation and Standardization procedures following Pharmacopoeial Laboratory of Indian Medicine (PLIM) guidelines. SKN, prepared as &lt;i&gt;Kuzhithylam&lt;/i&gt;, is used to treat &lt;i&gt;Swasakasam&lt;/i&gt; (Bronchial Asthma) in the Siddha system of medicine. The organoleptic characters of &lt;i&gt;Swasakasa Nei&lt;/i&gt; reveal that SKN was a black, thick semisolid with a smoky odour, greasy consistency, and free-flowing nature drug. Physicochemical analysis showed values for Saponification Value (202.19), Iodine Value (30), Acid Value (7.25%), Peroxide Value (0.58%), Refractive Index (1.462), Specific Gravity (0.9131 g/ml), Loss on Drying (34.17%), Total Fatty Matter (60.18%), Free Fatty Acids (1.06%), and Unsaponifiable Matter (0.98%). The congealing point was 19°C, with no mineral oil and definite oxidation on rancidity. HPTLC fingerprint analysis revealed multiple prominent peaks at various wavelengths. Microbial contamination tests showed no specific microbes, and aflatoxin assays confirmed SKN was free from Aflatoxins B1, B2, G1, and G2. Pesticide residue analysis detected no organochlorine, organophosphorus, or pyrethroids, and heavy metal analysis showed no trace elements or heavy metals. These standards affirm the authenticity, genuineness, and safety of SKN, contributing to its scientific validation.