Bacterial Contamination Research Articles

Flexible roles of TiO2 in enhancing carrier separation for the high photocatalytic performance of water treatment under different spectrum sunlight

Construction of heterogeneous-photocatalysts is an effective mean for enhancing charge separation, however, the specific roles of the individual components have not been thoroughly explored. In this article, a heterogeneous-photocatalyst, TiO2/MoO3-x, was constructed, revealing that the two components, TiO2 and MoO3-x, play varying roles under different light spectra. Under full spectrum light, an S-scheme mechanism was achieved, which preserved the high oxidizing and reducing property of MoO3-x and TiO2, facilitating an augmented generation of reactive oxygen species (ROS). Under visible light, the MoO3-x functioned as the donor of hot electrons and the TiO2 served as the receptor platform for these electrons. The presence of the interfacial electric field enabled the transfer of hot electrons, leading to an enhanced ROS generation. Consequently, the TiO2/MoO3-x achieved high photocatalytic activity under both full spectrum and visible light. The optimized TiO2/MoO3-x catalyst demonstrated outstanding antibacterial efficacy, achieving eradication rates of 98.1 % for Staphylococcus aureus, and 99.6 % for Escherichia coli respectively. Additionally, it exhibited substantial degradation activity with a rate of 0.028 min−1 for Rhodamine B (50 mg/L). Furthermore, the TiO2/MoO3-x membrane removed approximately 81.2 % of bacteria from surface water, underscoring the potential of the designed membrane in water purification systems. This article explored the distinct roles and corresponding charge transfer mechanisms of the TiO2 and MoO3-x under full spectrum or visible light, offering innovative ideas for the design of full-spectrum photocatalysts with high efficiency. The straightforward design of membrane-based filtering device demonstrated wide applications for treating wastewater for the removal of dye and bacterial contamination.

Isolation, identification, and antibiotic susceptibility profile of bacterial isolates from unused diapers sold in major markets in Enugu Metropolis: Clinical and policy perspectives.

Diapers, being one of the most used items for infant care, it is imperative that they are always free of contamination from microorganisms. The objective of this study is to determine the rate of bacterial contamination and the antibiotics profile of isolated bacteria from unused diapers sold in markets in Enugu Metropolis, southeast Nigeria. The study also investigated the effectiveness of the Nigerian Consumer protection laws towards maintaining the standard of care for infants and toddlers. Fifty pieces of different brands of diapers were sampled for bacterial contamination using standard bacteriological procedures. The results show that out of 50 samples analyzed, bacterial growths were identified in 9 (18%), of which five different bacterial species were isolated. The most prevalent being Escherichia coli and Staphylococcus aureus 3 (33.3%). Other bacteria isolated were Lactobacillus spp, Klebsiella spp, and Streptococcus spp 1 (11.1%). There was no statistically significant difference in the distribution of the bacterial contamination of diapers across the different brands(p>0.05). We conclude that baby diapers sold in markets in Enugu metropolis are prone to contamination with bacteria.We recommend that appropriate measures should be taken during the manufacturing process to reduce or prevent the incidence of bacterial contamination of diapers.

Eco-friendly activation of cotton textiles with LiNbO3 nanoparticles for enhanced self-cleaning and antibacterial performance

Cotton textiles play a universal role in everyday life, but they are prone to stain and serve as a primary channel for transmitting viruses and bacteria. The photocatalytic/antibacterial coatings are highly effective in addressing bacterial contamination on fabrics, although their efficacy diminishes with continuous use and washing. Here, insights are provided into the attachment of LiNbO3 on cotton surfaces using eco-friendly chemical activators to promote resistance to washing cycles, self-cleaning, and bactericide textiles. LiNbO3 nanoparticles were synthesized by low-temperature hydrothermal synthesis and directly applied to cotton fabric using immersion. The synthesized nanoparticles were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) N2 adsorption, diffuse reflectance for band gap determination, and Raman spectroscopy. A simple and effective impregnation method was used, promoting an ester-bond attachment between the cotton surface and the activators. Microscopy analysis (SEM) confirmed the successful deposition of the nanoparticles on cotton fabric. The LiNbO3 coating consisted of transparent layers and did not change the properties of cotton. Methylene blue stains are generally eliminated under UV light after 2 h using nanoparticles and activators. Antibacterial properties were evaluated under visible light through direct contact with bacterial suspensions and culturing. The coated cotton fabric that was activated with oxalic acid exhibited significant photocatalytic antibacterial activity against both Escherichia coli (gram-negative) and Staphylococcus aureus (gram-positive) bacteria, with bacterial reduction rate above 97 %, even after 10 washing cycles. This performance can be attributed to the effective coupling of LiNbO3 with oxalic acid in the cotton’s surface and its resistance to washing out. This study's novel synthesis and coating method offers an environmentally friendly, cost-effective, and straightforward approach for producing LiNbO3 self-cleaning and antibacterial surface-activated cotton.

BACTERIOLOGICAL QUALITY OF DRINKING WATER AND ASSOCIATED FACTORS AT COMMUNITY POINT SOURCES, IN ARUA DISTRICT, UGANDA

Background: Access to ample and safe water is vital, yet many globally lack this essential resource. Each year, 3.4 million individuals die from water-related diseases. Specifically, in Uganda, annual estimates suggest 89,000 cholera cases, resulting in 3,000 deaths. Objective: This study aimed to evaluate the bacteriological quality of drinking water and related factors in Arua Districts community water sources. Method: Utilizing a cross-sectional design and laboratory experiments, 140 samples were analyzed for coliform bacteria presence on filter membranes. Factors relating to contamination risks were identified via a sanitary inspection checklist. Data analysis was conducted using Stata/SE 17.0. Results: About 70.71% of samples contained bacteria, primarily total coliform. Significant risk factors included defective wastewater drainage (aOR: 19.7[5.34-72.72]), malfunctioning appliance parts (aOR: 10.7[2.52-45.92]), and inadequate or absence of fencing (aOR: 9.2[2.43-34.96]), each with a P-value <0.001. Conclusion: Ensuring safe drinking water requires treatment, quality monitoring, maintenance of appliances, and proper fencing to reduce bacterial contamination.

Validation of the diagnostic accuracy of the 3M™ Petrifilm™ coliform and aerobic count plates to measure colostrum bacterial contamination on Scottish dairy farms

A calf should receive 10–12 % of its bodyweight in high quality colostrum ( >50 g/L immunoglobulin) shortly after birth in order to confer passive immunity, with calves ideally receiving their first feed of colostrum in the first 1–2 hours of life (Godden et al., 2019). It is recommended (not validated) that total counts for bacteria and coliforms in colostrum should not exceed 100,000 colony forming units per mL (CFU/mL) and 10,000 CFU/mL, respectively. This study was conducted between March and September 2023. Eighty-five colostrum samples from 5 commerical dairy farms in Dumfries and Galloway in Scotland were purposively selected. Samples were collected from various stages during the colostrum harvest, storage and feeding process to provide multiple samples with variable (low, medium and high) bacterial contamination. The objective of this study was to validate the diagnostic accuracy of the 3 M Petrifilm™ Coliform Count Plate (CCP) and Aerobic Count Plate (ACP) for colostrum bacteriology. The Petrifilm™ Aerobic Count Plates were compared to 5 % sheep blood agar (SBA) (total bacteria counts, TBC), and the Petrifilm™ Coliform Count Plates were compared to MacConkey plates (MAC) (total coliform counts, TCC) and test sensitivity and specificity were calculated.Colostrum bacterial contamination was highly variable between farms (TBC median and interquartile range= 50,000CFU/mL and 546000CFU/mL; TCC median and interquartile range=100,750CFU/mL and 188,500CFU/mL). Overall correlation between the Petrifilms™ and reference plate measures was moderate (Spearman rho=0.38–0.47). The statistical accuracy of the Petrifilm™ systems and the test sensitivity were improved by lowering the bacterial cutpoint from 100,000CFU/mL to 91,000 CFU/mL for the aerobic counts plates and from 10,000CFU/mL to 1500 CFU/mL for the coliform count plates. The Petrifilm™ system could be used as a monitoring tool to provide quick and statistically accurate results for TBC and TCC but should not be seen as a comprehensive solution for poor colostrum hygiene.

Physio-chemical and bacteriological quality of well water from Kottayam district, Kerala

This study focused on determining of physio-chemical, Biological and Weighed water quality index of well water samples from twelve different stations in Kottayam district, Kerala. The water samples analyzed for physio-chemical parameters including pH, Electrical conductivity, TDS (Total Dissolved Solids), Total iron, Bacterial contamination and water quality index was calculated. All 120 samples were analyzed separately and were compared with the water quality standard prescribed by the APHA and IS 3025. It was found that the mean pH values showed slight variations ranging from 5.85±0.72- 7.19±2.09. The electrical conductivity showed variations ranging from 64.9±46.34- to 366.4±561.8. The well water samples were shown the TDS value under the permissible limit with a range of 42±39.8-248.2±393.03. A significant variation in total iron value was obtained from the Neendoor station and the range is 0.0033±0.0069-0.5525±1.703. Weighted water quality index was calculated based on physiochemical parameters and it is evident that the water from Neendoor station is unsuitable for drinking purposes. The bacterial concentrations of Pampady station showed 90% contamination and 65.8% of water samples were showed Indicator organism Escherichia coli.

Neutral red/carbon dots photodynamic disinfectant spray for sports mouthguards cleaning and perishable foods preservation

Bacterial contamination of medical devices and food poses critical threat to mankind's health. Although some antibiotics can kill bacteria, their mis/overuse in healthcare and agriculture has brought about serious bacterial antibiotic resistance. Thus, developing a convenient and rapid sterilization method becomes increasingly important. Herein, the nanocomposite NR@CDs was synthesized by the assembly of neutral red (NR) with carbon dots (CDs). Compared with NR, NR@CDs has stronger reactive oxygen species (ROS) generation ability. NR@CDs can photodynamically destroy both gram-positive and gram-negative bacteria efficiently, and the minimum inhibitory concentration (MIC) is 45 μg mL−1. NR@CDs spray is an eco-friendly sterilizing agent, with favorable biocompatibility and water-washability properties. Just 1 min of irradiation, NR@CDs spray can quickly and accurately kill the bacteria on the surface of the mouthguards (MGs). As the NR@CDs aqueous solution sprays on cherries, it can effectively prolong the quality guarantee period of perishable foods. The present work provides an innovative strategy to solve the global bacterial contamination and antibiotic resistance problems.

Integrating loop-mediated isothermal amplification with lateral flow assay to achieve a highly sensitive method for detecting Streptococcus suis Genome in raw pork

Streptococcus suis (S.suis), a zoonotic foodborne pathogen prevalent in Southeast Asia, poses a substantial threat to human and animal health because of its ability to cause severe and life-threatening illnesses. To address this challenge, a rapid and highly sensitive detection platform for S. suis in raw pork was developed by integrating loop-mediated isothermal amplification (LAMP) and a lateral flow assay (LFA), S. suis LAMP-LFA. LAMP reactions targeting the S. suis glutamate dehydrogenase (gdh) gene were optimized for specific detection of S. suis within 45 min at an isothermal temperature of 65 °C. The assay exhibited marked sensitivity, with a detection limit of 100 fg for genomic DNA extracted from S. suis cultures. Notably, this method showed no cross-reactivity with other bacterial contaminants commonly found in raw pork. The resulting LAMP amplicons were effectively detected using LFA, with a test limit of 101 CFU per 25 g of raw pork. S. suis LAMP-LFA proved to be highly specific and reliable, with no false-positives detected in spiked pork samples or pork samples containing other bacterial contaminants. Due to its high sensitivity, specificity, and rapid turnaround time, the proposed technique has immense potential as a field-deployable screening test for S. suis detection in raw pork, contributing to enhanced food safety and public health protection.

First report of wheat leaf spot disease caused by Curvularia inaequalis in China.

Wheat (Triticum aestivum) is an economically important crop widely cultivated in China. In August 2022, brown oval leaf spots with yellow halos were observed on approximately 10% wheat seedlings over an area of about 1 hectare in Xining City, Qinghai Province, which adversely affected wheat growth and production. Six diseased leaves were collected from the field in Huangyuan county (101°69' E, 37°04' N). The 0.5 cm × 0.5 cm pieces were cut from the border between healthy and diseased regions of the sampled leaves, surface sterilized for 10 s in 75% ethanol, followed by a 1% NaClO for 90 s, and rinsed three times with distilled sterile water. The pieces of leaf tissue were dried with sterile tissue, and plated on potato dextrose agar (PDA) amended with streptomycin (0.02 g/L) and ampicillin sulfate (0.05 g/L) to eliminate bacterial contamination. The dishes were placed in an incubator at 25°C for 72 h in dark. Three isolates, WGC201, WGC202 and WGC203, were obtained by a single-spore culture method. Fungal colonies on PDA media were dark green (Fig. 1A and 1B). Conidiophores were septate and geniculate terminals, while conidia exhibited straight or slightly curved forms with four transverse septa, the central cell being notably longer and wider than the others. The size of such conidia were 27.34 µm to 40.62 µm× 11.61 µm to 15.97 µm (number = 50) (av. 32.71 µm× 13.11 µm) (Fig. 1C and 1D) (Moubasher et al. 2010). The internal transcribed spacer (ITS) region of nuclear ribosomal DNA and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene were amplified and sequenced using universal primers ITS1/ITS4 and GPDF/GPDR (White et al. 1990; Berbee et al. 1999). DNA sequences were deposited into the NCBI database (ITS, PP789629, PP801333, and PP801574; GAPDH, PP849124, PP849125, and PP849126). Phylogenetic analysis with a neighbor-joining method based on the concatenated sequences of ITS and GAPDH genes showed that the three isolates clustered within a C. inaequalis branch (Fig. 2). Based on morphological and molecular identification, the fungal isolates were identified as C. inaequalis. The pathogenicity test was conducted in a greenhouse at 25°C using a spore suspension method and three isolates were used. Conidia were produced on PDA media (25℃) for 14 days. Plates were washed with sterilized distilled water and filtered with cheese cloth. Conidial suspension was adjusted to a concentration of 1×107 conidia/mL. Fifteen healthy seedlings of a wheat cultivar Xiaoyan-6 at a 3-4 leaf stage were inoculated by evenly spraying a 100mL spore suspension. Plants inoculated with sterile water served as a control. All plants were covered with plastic bags for 3 days. At 7 days after inoculation, all pathogen-inoculated plants showed similar symptoms (brown leaf oval spots with yellow halos) with those observed in the field, while all plants inoculated with sterile water showed no symptoms (Fig. 1E and 1F). The pathogen was reisolated from the symptomatic leaves and proved to be C. inaequalis. Morphological, molecular and pathogenic results indicated that C. inaequalis is the pathogen causing wheat leaf disease in China. The results are consistent with a previous report in Azerbaijan (Özer et al. 2020). To our knowledge, this is the first report of C. inaequalis causing spot disease on wheat in China. The occurrence, spread and economic importance to different wheat cultivars of the emerging disease in China will be further investigated and evaluated.

Penyuluhan Keamanan Pangan pada Ibu Rumah Tangga di RT 05 RW 06 Kelurahan Bandar Kidul Kota Kediri

Two important factors in preventing foodborne illness are food hygiene and sanitation. These efforts can reduce the risk of bacterial contamination of food. Some examples of hazardous materials in food are plastics, metals, borax, formalin, insecticides, and banned food additives such as benzoic acid, ascorbic acid, lactic acid, and citric acid. The objective of this outreach is to increase knowledge about food safety and how to manage it. The method of counseling to the general public includes coordination with the head of the RT, providing materials, giving pre- and post-tests, and evaluating activities carried out at the RT head's house on June 1, 2024 at 16.00-17.30. The results of this activity were an increase in pre and post-test scores on questions regarding storage temperature and the main purpose of food storage, from 50 to 70 and 95 to 100. The conclusion of this counseling is that there is an increase in housewives' knowledge about food safety on a household scale. Suggestions for further counseling are to increase the number of targets so that more housewives understand the importance of household-scale food safety.

Airborne Menace: Unveiling antibiotic resistance in bacteria around household waste containers

The increase in antibiotic-resistant bacteria and air contamination is a critical issue that requires significant scientific attention. This study was undertaken to isolate, identify, and detect antibiotic-resistant bacteria around garbage containers located in Jeddah city. A total of 40 plates were exposed to the air around garbage containers in major areas of the city such as Al-Salama, Al-Zahra, Al-Safa, and Al-Faisaliyah. The sample plates were taken to the laboratory within an hour for incubation. In total, 38 airborne bacteria were isolated and identified. Overall, 26.325 % of isolates showed multiple drug resistance (MDR). The highest percentage of resistance was seen against ampicillin (90 %), cefotaxime (80 %), cefuroxime (80 %), ceftrazime (80 %), augmentin (50 %), and cefoperazone (20 %). The multiple antibiotic index is seen between 0.16 and 0.5. Al-Safa and Al-Salama were regions that showed the highest contamination of airborne antibiotic-resistant bacteria. These results suggest that the selected area has a significant prevalence of multiple drug resistance to routinely used antibiotics. Due to selection pressure, contaminants like bacteria or other pollutants around garbage containers cause antibiotic resistance, which leads to a global public health crisis. Therefore, to combat antimicrobial resistance, a collaborative, multidisciplinary, and regulatory approach is required.

Reproductive Tract Microbial Transitions from Late Gestation to Early Postpartum Using 16S rRNA Metagenetic Profiling in First-Pregnancy Heifers.

Studies in recent years indicate that reproductive tract microbial communities are crucial for shaping mammals' health and reproductive outcomes. Following parturition, uterine bacterial contamination often occurs due to the open cervix, which may lead to postpartum uterine inflammatory diseases, especially in primiparous individuals. However, investigations into spatio-temporal microbial transitions in the reproductive tract of primigravid females remain limited. Our objective was to describe and compare the microbial community compositions in the vagina at late gestation and in the vagina and uterus at early postpartum in first-pregnancy heifers. Three swab samples were collected from 33 first-pregnancy Holstein Friesian heifers: one vaginal sample at gestation day 258 ± 4, and vaginal and uterine samples at postpartum day 7 ± 2. Each sample underwent 16S rRNA V4 region metagenetic analysis via Illumina MiSeq, with bioinformatics following Mothur MiSeq SOP. The reproductive tract bacterial communities were assigned to 1255 genus-level OTUs across 30 phyla. Dominant phyla, accounting for approximately 90% of the communities, included Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes, and Fusobacteria. However, the results revealed distinct shifts in microbial composition between the prepartum vagina (Vag-pre), postpartum vagina (Vag-post), and postpartum uterus (Utr-post). The Vag-pre and Utr-post microbial profiles were the most distinct. The Utr-post group had lower relative abundances of Proteobacteria but higher abundances of Bacteroidetes, Fusobacteria, and Tenericutes compared to Vag-pre, while Vag-post displayed intermediate values for these phyla, suggesting a transitional profile. Additionally, the Utr-post group exhibited lower bacterial richness and diversity compared to both Vag-pre and Vag-post. The unsupervised probabilistic Dirichlet Multinomial Mixtures model identified two distinct community types: most Vag-pre samples clustered into one type and Utr-post samples into another, while Vag-post samples were distributed evenly between the two. LEfSe analysis revealed distinct microbial profiles at the genus level. Overall, specific microbial markers were associated with anatomical and temporal transitions, revealing a dynamic microbial landscape during the first pregnancy and parturition. These differences highlight the complexity of these ecosystems and open new avenues for research in reproductive biology and microbial ecology.

Vancomycin Soaking to Reduce Intraoperative Contamination by Cutibacterium acnes During the Latarjet Procedure

Background: Postoperative infection after the Latarjet procedure, ranging from 1% to 6%, can compromise the functional outcome of young athletes. Cutibacterium acnes is a main pathogen as a consequence of an intraoperative contamination. Purpose: To evaluate intraoperative contamination with C. acnes and the effectiveness of the local application of vancomycin during the Latarjet procedure. Study Design: Cohort study; Level of evidence, 2. Methods: This was a single-center study including 75 patients (mean age, 26 years; range, 15-55 years) operated on for anterior shoulder instability with the primary open Latarjet procedure; they underwent the same protocol of skin preparation and preoperative prophylactic antibiotics. Three groups of 25 patients were created and divided sequentially, without the results of each group being known before the end of the study: group A (5 mg/mL of vancomycin), group B (20 mg/mL of vancomycin), and group C (control group with no vancomycin). Swab samples of the coracoid were taken before sectioning the coracoid process (time 1) and after its preparation (time 2). The coracoid was then wrapped in gauze impregnated with different concentrations of vancomycin, except for group C. A final sample (time 3) was taken before screwing the bone block onto the glenoid. All samples were cultured for 21 days, and patients underwent clinical and radiological follow-up for 6 months. Results: The C. acnes contamination rates at times 1, 2, and 3 were 25%, 44%, and 45%, respectively, without significant difference. There was no significant difference between groups A and B with respect to the number of positive cultures at each time point. Of 9 positive cultures at time 1, all were still positive at time 3 in group A, whereas 3 of 5 were negative in group B (P = .027). The rate of C. acnes at time 3 in the control group was higher than that in the 2 other groups (68% vs 44% for group A and 20% for group B; P = .003). Body mass index was the only prognostic factor for a C. acnes–positive culture (26.05 ± 3.39 vs 23.34 ± 2.33; P = .018). No clinical infection was reported at the 6-month postoperative follow-up. Conclusion: The rate of C. acnes contamination ranged from 25% to 68% during the open Latarjet procedure in young athletes. Vancomycin reduced the bacterial contamination when it was used at high concentrations in a gauze wrap on the coracoid. The type of C. acnes detected and its clinical implications remain to be studied.

Study protocol of the FRENCH24-ANIS study: postoperative anti-infective strategy following pancreaticoduodenectomy in patients with preoperative biliary stents—an intergroup FRENCH-ACHBT-SFAR prospective randomized controlled trial

BackgroundDespite advances in surgical techniques and care, pancreatoduodenectomy (PD) continues to have high morbidity and mortality rates. Complications such as sepsis, hemorrhage, pulmonary issues, shock, and pancreatic fistula are common postoperative challenges. A key concern in PD outcomes is the high incidence of infectious complications, especially surgical site infections (SSI) and postoperative pancreatic fistula (POPF). Bacteriobilia, or bile contamination with microorganisms, significantly contributes to these infections, increasing the risk of early postoperative complications. The occurrence of SSI in patients who undergo hepatobiliary and pancreatic (HPB) surgeries such as PD is notably higher than that in patients who undergo other surgeries, with rates ranging from 20 to 55%. Recent research by D'Angelica et al. revealed that, compared to cefoxitin, piperacillin/tazobactam considerably lowers the rate of postoperative SSI. However, these findings do not indicate whether extending the duration of antibiotic treatment is beneficial for patients at high risk of bacterial biliary contamination. In scenarios with a high risk of SSI, the specific agents, doses and length of antibiotic therapy remain unexplored. The advantage of prolonged antibiotic prophylaxis following PD has not been established through prospective studies in PD patients following biliary drainage.MethodsThis is an intergroup FRENCH-ACHBT-SFAR multicenter, open-labelled randomized, controlled, superiority trial comparing 2 broad-spectrum antibiotic (piperacillin/tazobactam) treatment modalities to demonstrate the superiority of 5-day postoperative antibiotic therapy to antibiotic prophylaxis against the occurrence of surgical site infections (SSI) following pancreaticoduodenectomy in patients with preoperative biliary stents. The primary endpoint of this study is the overall SSI rate, defined according to the ACS NSQIP, as a composite of superficial SSI, deep incisional SSI, and organ/space SSI.In addition, we will analyze overall morbidity, antibiotic resistance profiles, the pathogenicity of bacteriological and fungal cocontamination, the impact of complications after bile drainage and neoadjuvant treatment on the bacteriological and fungal profile of biliculture and cost-effectiveness.ConclusionThis FRENCH24-ANIS study aims to evaluate 5-day post-operative antibiotic therapy combined with antibiotic prophylaxis on the occurrence of surgical site infections (SSI) following pancreaticoduodenectomy in patients with preoperative biliary stents.Trial registrationClinicaTrials.gov number, NCT06123169 (Registration Date 08–11–2023); EudraCT number 2021–006991-18; EUCT Number: 2024–515181-14–00.

Temperature has a greater effect than salinity on microbial survival in saltwater from a single equine hydrotherapy unit.

To determine the ability of bacteria commonly isolated from equine limb wounds to survive in saltwater obtained from an equine hydrotherapy unit at different salinity concentrations and temperatures. Saltwater samples were obtained over a 2-week period (January 22, 2024 to February 2, 2024) from an equine hydrotherapy unit used for clinical patients, kept at either full salinity per manufacturer recommendations or diluted to half salinity to mimic the dilution that likely occurs in the clinical setting between cases when holding tanks are replenished with tap water only. Samples were then autoclaved to eliminate preexisting bacterial contamination before individual inoculation with Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus zooepidemicus. Each inoculated sample was maintained at 2, 22, or 44 °C to represent typical holding tank conditions. The bacterial concentration was determined at each condition every 24 hours up to and including 96 hours. The lower limit of detection was set at 1 CFU/mL. Salinity did not affect bacterial survival. Bacterial concentrations generally decreased with increasing temperature over time. Escherichia coli, S aureus, and S zooepidemicus concentrations decreased to the lower limit of detection at 44 °C by 24 to 48 hours, while P aeruginosa concentrations significantly decreased over 24 hours but remained well above the lower limit of detection. Common bacterial isolates of equine limb wounds can survive in typical saltwater hydrotherapy conditions. Further investigation is warranted to determine the clinical relevance of these findings including protocols for hydrotherapy unit disinfection, wastage of treatment water, and case inclusion/exclusion criteria.

Hydrothermal synthesis of metal-polyphenol coatings on titanium implant for enhancing antioxidant and antibacterial properties

Oxidative stress and bacterial contamination are important causes of titanium implant failure. Although several titanium surface modification techniques have been developed, it is still challenging to combine antioxidant and antibacterial properties. Here, in this study, cerium/zinc-epigallocatechin gallate (EGCG) (ECe&Zn) coatings were constructed on titanium surfaces with antioxidant and antibacterial properties based on metal-polyphenol coating technology and hydrothermal synthesis. SEM and XPS results confirmed the successful preparation of the ECe&Zn coating. Antioxidant experiments showed that Ti-ECe&Zn possessed multiple antioxidant enzyme-like activities and good free radical scavenging ability. In vitro biological evaluation revealed that Ti-ECe&Zn was not cytotoxic and had excellent antibacterial properties. The present work provided a simple and effective method for endowing medical implants with both multiple antioxidant and antibacterial properties.

Application of miniaturized most probable number method for bacterial detection in water samples: detection of multi-drug-resistant Ralstonia insidiosa in drinking water.

The detection of bacterial contamination in drinking water is essential for monitoring the spread of foodborne diseases. We developed a simple, portable, and low-cost method of mini most probable number (mini MPN) to semi-enumerate bacterial suspension in water as a drinking water analogue. In this study, there is no significant difference between mini MPN and the standard method, technique plate count (TPC), at 10 and 100 CFU/ml Klebsiella pneumoniae suspension with a P-value of 0.28. For the ease-of-use aspect of this method, we tested several variables to prove it can be mass-applied in society. The usage of a sterile-plastic pipette, sample inoculation conducted in a biosafety cabinet (BSC), the usage of a 3-month storage medium, and incubation temperature conducted at room temperature compared to aseptic standard laboratory technique showed P-value > 0.05. In a trial for this method, we used commercialized drinking water for bacterial enumeration and characterization. We found multi-drug resistant (MDR) Ralstonia insidiosa which was resistant to at least four antimicrobial classes, including aminoglycosides, penicillins, cephalosporin, and carbapenem. Vitek 2 Compact was used for bacterial identification and antimicrobial susceptibility testing. A virulence test in Omphisa fuscidentalis larvae showed R. insidiosa strain D had a low virulence.

Using Next-Generation Sequencing to Understand Infection Prevention in Surgical Treatment of Upper Extremity Fractures-A Prospective Cohort Study.

Postoperative fracture site infection can lead to notable patient morbidity, increase cost of care, and further contribute to healthcare disparities globally. Dogma suggests surgical blades as a vehicle for introducing bacteria into the surgical site; however, there is a paucity of literature to support this claim. This study uses advanced DNA sequencing to detect bacterial DNA on surgical blades used in upper extremity fracture surgeries. This was a prospective study, conducted at a high-volume level 1 trauma center. All acute, closed upper extremity fractures requiring surgical stabilization were consecutively enrolled in a prospective fashion. The primary end point was the presence of bacterial DNA on the surgical blade using next-generation sequencing (NGS). At the time of surgery, two blades were sterilely opened. One blade served as the control while the other was used for the initial skin incision. Two negative control blades were opened directly into a sterile container. Two positive control blades were used for skin incision through known infections. All samples were sent for NGS analysis. Forty patients were enrolled in this study. The median age was 33.5 years, and 30% were female; the median body mass index was 26.52. Humerus fractures were the most common injury (N = 17, 42.5%), followed by clavicle fractures (13, 32.5%) and radius/ulna fractures (10, 25.0%). NGS analysis revealed no contamination of test blades used for skin incision. Three control blades tested positive for bacterial DNA. Negative control blades tested negative for bacterial DNA (0/2); the positive control blades resulted positive for bacterial DNA contamination (2/2). Surgical blades used for skin incision in the upper extremity are not contaminated with bacterial DNA as analyzed by NGS. This finding challenges previous surgical dogma regarding surgical blade contamination and supports that the same surgical blade can safely be used for deeper dissection. Level II study: IRB approval-IRB#848938.

Bacterial contamination in the different parts of household air conditioners: a comprehensive evaluation from Chengdu, Southwest China.

Air flow driven by air-conditioner has a significant impact on the indoor environment, however, the bacterial contamination conditions in the different parts of air-conditioners have not been fully elucidated. In this study, we assessed the bacterial pollution in the four parts, including air outlet, filter net, cooling fin and water sink, of ten household air-conditioners quantitatively and qualitatively from Chengdu, southwestern China. The microbial cultivation results showed the large total bacterial counts of 5042.0, 9127.6, 6595.1, and 12296.2 CFU/cm2 in air outlet, filter net, cooling fin, and water sink. Furthermore, the sequencing data showed that these four parts displayed different bacterial characteristics. At the level of genus, Caproiciproducens and Acidipropionibacterium were predominant in air outlet. Bacillus, Acinetobacter, Paracoccus, and Corynebacterium were detected as the characteristic bacteria in filter net. For cooling fin, Rhodococcus, Achromobacter, and Nocardioides were the dominant bacteria. The genera of Methylobacterium-Methylorubrum, Brevibacterium, Stenotrophomonas, and Psychrobacter were identified as the bioindicators in water sink. The bioinformatic analysis on the sequencing data illustrated that the bacteria from air-conditioners were associated with metabolic disturbance. This study reveals the distinct bacterial compositions in the different parts of air-conditioner, and provides new clues for the non-negligible bacterial pollution in this common appliance from Chinese households.

Antibiotic-resistant bacteria contaminating leafy vegetables in Saudi Arabia’s eastern region

BackgroundFood-associated antibiotic-resistant bacteria can cause infections that may critically impact human health. The objectives of this study were to determine the microbial contamination level of green leafy vegetables and their antibiotic resistance pattern.MethodsSixty-three samples of leafy vegetables were collected from Dammam Central Fruit and Vegetables Market from January to June 2023. The vegetables included lettuce (Lactuca sativa), parsley (Petroselinum crispum), and watercress (Nasturtium officinale). Samples were tested by standard microbiological techniques for identification and antibiotic susceptibility testing.ResultEight types of bacteria belonging to six different genera were detected. Enterobacteriaceae family was represented by four genera: Klebsiella, Proteus, Morganella, and Enterobacter. The other two genera were Pseudomonas and Aeromonas. Enterobacter cloacae was the most abundant organism, followed by Pseudomonas putida and Aeromonas sobria. On the other hand, Morganella morganii, Aeromonas hydrophila, and Proteus mirabilis were the least abundant. The three vegetable types had different levels of bacterial contamination. All isolated organisms were sensitive to penicillin, cephalosporin, aminoglycoside, and fluoroquinolone. However, Klebsiella oxytoca, M. morganii, and K. pneumonia showed resistance to ampicillin. A. hydrophila, Morganella morganii, and E. cloacae showed resistance to amoxicillin. M. morganii and E. cloacae were found to be resistant to cefalotin. Moreover, A. hydrophila, M. morganii, and E. cloacae were resistant to cefoxitin. Again, A. hydrophila was found to be resistant to imipenem. Only M. morganii was resistant to Ciprofloxacin. Two isolates, P. mirabilis and M. morganii were resistant to tigecycline. Another two, M. morganii and P. mirabilis were resistant to Nitrofurantoin. Only M. morganii was found to be resistant to trimethoprim.ConclusionThis study aligns with the broad consensus in the literature about the significance of bacterial contamination in vegetables and the public health implications. The unique focus on antibiotic resistance patterns adds an essential dimension to the existing body of knowledge.