Microbiological Assessment Research Articles

Assessing microbial risks of Escherichia coli: A spatial and temporal study of virulence and resistance genes in surface water in resource-limited regions.

Environmental microbial pollution can potentially cause illnesses and deaths among human populations. Environmental factors such as geomorphology, land use, human activities, and seasonality could influence pathogen dissemination. This study performed a space-temporal analysis of Escherichia coli concentrations, virulence (eaeA, bfpA, stx2, aatA, and st), and resistance (tetA, blaTEM, blaOXA, Intl-1, Intl-2, sul-1, and sul-2) genes in surface water within the Virilla sub-watershed, Costa Rica. The research employs microbiological, geostatistical, and quantitative microbial risk assessment (QMRA) techniques to evaluate the health risks associated with diarrheagenic E. coli. Samples collected monthly over a year were analyzed for fecal coliforms, E. coli, Enterococcus faecalis, physicochemical parameters, and the presence of virulence and resistance genes. The geographically weighted regression model identified significant associations between the virulence and resistance genes presence and environmental factors influence such as land use, slope, altitude, and seasonal changes. The results show that urban and grazing land use significantly influence the presence of resistance genes, while human fecal pollution is associated with higher concentrations of virulence genes. Seasonal variations showed that wet seasons contributed to increased gene presence (number of positive samples) and diversity (variety of virulence and resistance genes) compared with dry season. The QMRA results indicated that the total health disease burden was higher than the benchmark for drinking water recommended by WHO (1.00×10-6 DALY - Disability-Adjusted Life Years - per person per year) by between one and four magnitudes orders, particularly in regions with urban and grazing land use, human fecal pollution class, and lower altitudes. This study highlights the relevance of integrating environmental and microbial data to enhance water quality management and public health strategies in resource-limited regions. It underscores the need for targeted interventions, such as improved wastewater treatment and establishing buffer zones, to mitigate the risks associated with microbial pollution in surface waters.

Bacteriospermia in men among infertile couples in the Nepalese population

Infection of the male urogenital tract or male accessory glands is considered one of the important causes of male infertility, and results in the presence of bacteria in semen affecting the fertility potential of men. This study aims to understand the rate of seminal infection in infertile men, and its association with semen parameters related to fertility potential. The study was carried out from June 2021 to July 2022, in which 217 semen samples were collected from male partners of couples consulting for fertility complaints in a fertility center in Nepal. Analysis of semen parameters was done following the WHO guidelines for human semen analysis, 2021. Microbiological assessment of semen by culture-based approach showed bacteriospermia among 25.3% of samples. Staphylococcus aureus was the predominant isolate in semen. The volume of semen was reduced (p = 0.001 at 95% confidence interval) with bacteriospermia. The concentration, total motility, morphology, and vitality of spermatozoa in the samples tended to be negatively impacted due to bacteriospermia, however, the associations were insignificant at 95% CI. Our study indicates impairment of semen parameters is partially associated with bacterial infection, and hence bacteriospermia may be an important cause of male infertility. Our data represent a baseline for future in-depth studies on bacterial infection in the semen of infertile men in Nepal.

Microbial Assessment of Herbal Tea Production with Natural Ingredients

Purpose: The study aimed to assess the microbial safety and quality of herbal tea production using natural ingredients. The objectives of the research were to: determine the sensory characteristics of herbal tea produced using lemongrass, cloves, “precise”, and negro pepper. To evaluate critical control points for microbial contamination. Design/Methodology/Approach: The study employed an experimental research design with staff from the Western Regional House of Chiefs as the population. A sample size of one hundred (100) respondents was selected for the study using purposive and convenience sampling methods. The sensory evaluation utilised a 7-point hedonic scale, whilst mineral content and proximate analysis were conducted. Analysis of Variance (ANOVA) was employed to evaluate differences among the various tea samples. Findings: Participants showed a strong preference for Lemongrass (201) and Basic tea (204) due to their delightful taste experience, which encompassed appealing attributes such as colour, aroma, texture, and aftertaste. The investigation revealed notable differences in the nutrient composition of the herbal tea samples. Cloves (202) stood out for its higher protein and fat contents, with the highest counts of both aerobic microorganisms and yeast and molds, while Lemongrass was found to have more fibre and carbohydrates. Research Limitation: This research focused on the production of herbal tea using negro, pepper, “prekese”, cloves and lemongrass. Practical Implication: Healthcare systems benefit from validated safety standards for herbal products, reducing the burden of foodborne illnesses and contamination-related health issues. Social Implication: The research contributes to food security by ensuring the safety and reliability of traditional herbal beverages while maintaining their cultural significance. Originality/Value: This research contributes to food safety science by bridging traditional herbal knowledge with modern microbiological assessment methods, potentially influencing industry standards and regulatory frameworks.

ИССЛЕДОВАНИЕ ВОЗМОЖНОСТИ ОБОГАЩЕНИЯ МЯСНЫХ ПОЛУФАБРИКАТОВ БЕЛКОВЫМИ КОНЦЕНТРАТАМИ КРЕСТОЦВЕТНЫХ КУЛЬТУР

The purpose of the study is to develop a recipe for a semi-finished meat product with the addition of a protein concentrate of cruciferous crops – camelina and rapeseed grown in the agroecological conditions of the Krasnoyarsk Region. Research objectives: to study the amino acid composition of cruciferous protein concentrates, to assess the quality and food safety indicators; to determine the rational dosage of the protein concentrate of cruciferous crops – rapeseed and camelina in the semi-finished meat product; to conduct an organoleptic evaluation of the finished semi-finished meat product with the addition of cruciferous protein concentrates; to determine the quality and safety indicators of the developed ready-made semi-finished meat product. Objects of study: protein concentrates of cruciferous rapeseed and camelina obtained in the research laboratory of the Federal State Budgetary Educational Institution of Higher Education "Krasnoyarsk State Agrarian University"; developed meat semi-finished products with the addition of cruciferous protein concentrates. To obtain meat chopped semi-finished products, the following raw materials were used: beef cutlet meat – according to TU 9214-001-92075951; raw beef fat – according to TU 100098867.332-2013; wheat bread – according to GOST 27842; breadcrumbs – according to GOST 28402; fresh onion – according to GOST 1723; ground black pepper – according to GOST 29050; table salt – according to GOST R 51574. Methods according to GOST 32951 and TU 9214-039-52115729-2015 were used to determine the quality indicators of protein concentrate and product. The microbiological assessment of the test samples was carried out in accordance with TR CU 034/2013 "On the safety of meat and meat products" and TR CU 021/2011 "On food safety". As a result of the study, the amino acid composition of rapeseed and camelina protein concentrates, which include all essential amino acids, was studied. The organoleptic, physico-chemical parameters of protein concentrates and their safety have been determined. A rational dosage of cruciferous protein concentrate was established, which was 3 % instead of minced meat. The indicators of quality and safety of the developed meat chopped semi-finished product were determined and their compliance with regulatory documentation was confirmed.

Microbiological and physicochemical water quality assessments of the Upper Basin Litany River, Lebanon.

The Litany River has encountered severe environmental pollution. This study focused on assessing the pollution level in the upper basin of the Litany River by monitoring seasonal variation of water quality and testing physicochemical parameters and microbial qualities. A total of 72 freshwater samples were taken from six sites for 1 year during the four seasons. The microbiological parameters included total coliform, fecal coliform, and Escherichia coli counts. The physicochemical parameters comprised pH, total dissolved solids, nitrate, sodium, potassium, biochemical oxygen demand, chemical oxygen demand, total nitrogen, and total phosphorus. The microbiological quality of samples was evaluated by comparing the fecal pollution indicators loads to the SEQ-EAUX2003 standard for irrigation, and the physicochemical analyses were assessed according to Lebanese Standards Institution (LIBNOR) NL161: 2016 and the World Health Organization (WHO) Guidelines for Water Quality. The results revealed that most physicochemical parameters are not within the permitted limit of LIBNOR and WHO, especially in sites S2, S3, and S6 during the dry seasons. The pH ranged between 6 and 8.16. The total dissolved solids reached 1948 mg/L. The nitrate, sodium, and potassium ranged between 0 and 253 mg/L. The total nitrogen and total phosphorous reached 103 and 5.16 mg/L, respectively. The chemical oxygen demand reached 2210 mg/L, and the biochemical oxygen demand reached 732 mg/L. Concerning the microbiological analysis, fecal pollution was detected in all sites during all seasons, with detectable higher values during the dry seasons, and all samples were considered to be non-conforming, with significant spatiotemporal variation of most parameters. Our results highlight the need to take measures to prevent the high level of pollution. This could be achieved by monthly water quality monitoring of the upper basin and introducing appropriate guidelines to detect pathogens and toxic chemicals that affect the entire ecosystem and lead to severe public health issues.

Microbiological Assessment and Evaluation of Virus Yield in Germ-free Chicken Eggs

Background Increasing yield will have major implications for vaccine manufacturers. Internal bacterial contamination of specific pathogen-free (SPF) eggs results in batches of vaccines being rejected and may negatively impact vaccine yield. Objective The objectives of this study were to analyze Germ-Free (GF) eggs microbiologically and evaluate the yield of H1N1 when compared with SPF eggs from 2 different suppliers. Methods The contents of GF eggs were analyzed using three different methods (sterility test, total viable count, and bioluminescence). Eggs from each source were inoculated with H1N1 virus. Chick Embryo Fibroblast (CEF) cell cultures were generated from GF and SPF eggs from both suppliers and infected with H1N1. The supernatant was titrated for viral Haemagglutinin activity and virus infectivity while cellular RNA extracts were assayed for Interferon (α and β) gene expression by RT-qPCR using gene-specific primers. Results The analysis of GF eggs confirmed that the contents were sterile. The batch yield of GF eggs was ~1.2-fold and ~1.8-fold higher than SPF supplier 1 and SPF supplier 2 virus yields, respectively. Replication of H1N1 was 2-fold higher in CEF derived from GF eggs than CEF derived from SPF supplier 1 or SPF supplier 2. IFN-β antiviral response of GF-derived CEF cells was 2-fold lower than SPF supplier 1-derived and ~3-fold lower than SPF supplier 2-derived CEF cells. Conclusion The content of GF eggs was sterile. The yield of H1N1 was higher in GF eggs than in SPF eggs, and the higher yield was associated with a significant reduction in interferon Beta levels.

Microbiological Quality Assessment of Meatball Samples Collected from Businesses with Different Pricing Strategies

Objective: The purpose of this study was to evaluate the microbiological quality of meatball samples collected from establishments employing different pricing strategies. Materials and Methods: Samples were obtained from low-priced establishments (Business I) and high-priced establishments (Business II) and were analyzed for total aerobic mesophilic bacteria (TAMB), yeasts and molds, coliform bacteria, Staphylococcus aureus, Escherichia coli, Salmonella spp., and Listeria monocytogenes. Results: Both groups of samples complied with Turkish Food Codex standards for TAMB and S. aureus, while yeast and mold count in Business I samples exceeded the permissible limits. Salmonella spp. was detected in 3.3% of the samples from Business I and 6.6% from Business II, whereas L. monocytogenes was not detected in any of the samples. Conclusion: The study findings showed that there was no significant difference in microbiological quality between the two groups, except for yeast and mold counts. It was also concluded that there was no direct relationship between product price and hygienic quality. Keywords: Food pricing strategies, Hygienic quality, Meatball, Microbiological quality

Microbiological water quality assessment of swimming pools and jacuzzis in Northern Greece: a retrospective study.

Swimming pools and jacuzzis can pose significant public health risks as potential sources of infections. The present study aimed to evaluate the prevalence and concentration of microbiological indicators in recreational water facilities in Thessaloniki, Northern Greece, focusing on their hygiene status before and after the COVID-19 pandemic. Between January 2018 and December 2022, 1114 water samples were analyzed by the regional Water Hygiene Laboratory at Aristotle University of Thessaloniki, using standardized ISO methods. Jacuzzis exhibited the highest microbial contamination, particularly for Pseudomonas aeruginosa (19.7%), while indoor adult pools showed the lowest. Overall, P. aeruginosa was found in 12.4% of samples, with the highest concentrations in jacuzzis (median: 30 CFU/100 ml). Significant seasonal variations were identified in the prevalence of total microbial flora (p < 0.001) and total coliforms (p = 0.03), as well as in the concentration of residual chlorine (p = 0.023). During the COVID-19 pandemic, microbial prevalence decreased across facilities. We concluded a strong compliance with Greek and international microbiological standards. The decline in microbial prevalence overtime likely reflects the impact of the strict hygiene measures implemented during the pandemic. These findings highlight the importance of maintaining rigorous hygiene practices to protect public health.

A Novel Non-Alcoholic Einkorn-Based Beverage Produced by Lactic Acid Fermentation: Microbiological, Chemical, and Sensory Assessment.

Einkorn (Triticum monococcum L. ssp. monococcum) is gaining renewed interest for its high nutritional value and digestibility. Lactic acid fermentation could enhance these properties by improving micronutrient bioavailability, sensory properties, and shelf life. This study aimed to develop a novel non-alcoholic einkorn-based beverage through lactic acid fermentation. A multiple-strain starter was selected based on acidifying properties and inoculated into an einkorn-based substrate to produce a yogurt-like beverage. Prototypes were evaluated through physico-chemical, chemical, and microbiological analyses and compared to uninoculated controls. A sensory analysis was also performed to assess flavor attributes before and after lactic acid fermentation. The inoculated starter culture reached a load of approximately 9 Log CFU g⁻¹ and remained viable throughout storage, leading to an increase in lactic acid concentration and high titratable acidity, corresponding to low pH values. Total polyphenol content increased during fermentation and remained stable during storage, whereas antioxidant activity did not show significant differences over time. An increase in monosaccharides, acids, and ketones was observed during fermentation and storage. The prototypes exhibited a distinctive proximate composition, along with yogurt and fruity aroma notes. These results suggest the feasibility of producing a safe and stable non-alcoholic einkorn-based fermented beverage with appealing sensory characteristics.

Combined stochastic modelling of pathogenic and spoilage microorganisms.

Quantitative microbiological risk assessment (QMRA) of pathogens in food safety is well established, but steps are being taken to expand this methodology to food spoilage. Parallels can be drawn between the steps involved in a QMRA for pathogens and its application to specific spoilage organisms (SSO). During hazard characterisation for pathogens, the appropriate dose-response model is used to link the hazard level to the health outcome by estimating the probability of illness, resulting from the ingestion of a certain dose of the hazard. The dose-response model, in the case of food spoilage, may be translated into a spoilage-response relationship linking the spoilage-level with the probability the consumer will discard the food and not consume it. Such models are developed with sensory testing, assessing consumers sensitivity to microbial spoilage quality defects and correlating them to the SSO concentration. Ignoring food spoilage before the stated expiration date can lead to the final health risk being overestimated, since cases in which the food item poses a real risk to the consumer but is not consumed due to perceived spoilage are not excluded. Plenty of risk assessments have been carried out for pathogens in different RTE foods. What is missing is the integration of the two approaches into a single model that can estimate the risk of illness, factoring in the variability of consumer responses to spoilage. The spoilage-response relationship was combined with a stochastic modelling approach for lactic acid bacteria (LAB) and Listeria monocytogenes growth, also taking into account microbial interaction between LAB and L. monocytogenes (Jameson effect) to increase accuracy. The comparison of results between the 'Baseline' and the 'Spoilage-informed' approach showed significant difference in listeriosis cases, both for consumers under and over 65 years old. These results may suggest, that the hypothesis about overestimation of listeriosis risk in case of not taking into account product spoilage is correct. The combined QMRA model developed in the present study can be a useful tool for risk management decisions in the meat industry.

Exploring frameworks for quantitative risk assessment of antimicrobial resistance along the food chain.

Campylobacter is one of the most reported causes of bacterial gastroenteritis worldwide. Birds are the predominant reservoirs for thermotolerant Campylobacter, therefore consumption of contaminated and undercooked poultry products represents one of the major transmission routes for campylobacteriosis. In addition to foodborne diseases, another relevant public challenge is the silent pandemic of antimicrobial resistance (AMR), impacting also the food chain. The occurrence of antimicrobial-resistant Campylobacter in broiler meat poses a significant threat to public health. In this context, quantitative microbiological risk assessment (QMRA) might support policy-makers in addressing these challenges. Hence, this project aimed to describe the current status of knowledge on occurrence of AMR Campylobacter at a global scale, with focus in estimating the prevalence of fluoroquinolone-resistant Campylobacter isolated from broiler meat at retail level. Following the drafting of a dedicated protocol, a systematic literature review and meta-analysis were conducted. Based on the extracted data, after the determination of the proportion of AMR isolates, the proportions were compared by Campylobacter species, geographical regions, processing step and sampling matrices. Meta-analysis allowed the estimation of the pooled prevalences of resistant isolates by regions and species, combining the findings from different independent studies in a comparable way. In terms of future perspectives, the outcome of this project will support future risk assessment and provide valuable inputs for estimating consumer exposure to AMR Campylobacter via broiler meat consumption. In conclusion, this report will provide a general overview of activities, preliminary results and research performed during the EU-FORA fellowship programme (2023/2024).

Training in modern statistical methodologies and software tools for the definition and analysis of (stochastic) quantitative microbial risk assessment models with relevant food products for the Italian and Spanish food supply chains.

The fellowship, entitled 'Training in modern statistical methodologies and software tools for the definition and analysis of (stochastic) quantitative microbial risk assessment models with relevant food products for the Italian and Spanish food supply chains', was implemented at the Universidad Politécnica de Cartagena (UPCT), Spain. Supervised by Dr. Alberto Garre and Prof. Pablo S. Fernandez and coordinated by Dr. Virginia Filipello of the Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Italy, the fellowship aimed to provide hands-on training in quantitative microbial risk assessment (QMRA). The fellow benefited from UPCT's expertise in microbiological risk assessment, gaining knowledge of methodologies, terminologies and software tools essential for QMRA. The focus of the fellowship was on the risks associated with plant-based milk products, which are increasingly popular as sustainable alternatives to dairy milk. Despite the heat treatments these beverages undergo to ensure safety, risks persist, such as cross-contamination during post-processing or the survival of heat-resistant spores like Bacillus cereus. A recent European outbreak linked to contaminated oat milk underscored the importance of assessing these risks. The project was conducted in two phases: first, at UPCT's Food Microbiology Laboratory, where the fellow handled and characterised the thermal resistance of various B. cereus strains using a thermoresistometer; and second, through remote analysis of experimental data using risk analysis software tools. The fellow developed skills in microbiological techniques, such as spore preparation and thermal resistance evaluation, and became proficient in data analysis using the R programming language and the biorisk package. The fellowship culminated in the development of a QMRA model to estimate the likelihood of B. cereus-related foodborne illness from plant-based milks, considering different heat treatments and bacterial strains. The fellow's training covered all stages of risk assessment, including hazard identification, exposure assessment, hazard characterisation and risk characterisation, providing a comprehensive foundation for a career in food safety and microbial risk assessment.

A clinical and microbiological assessment of the efficacy of chemo-mechanical caries removal versus conventional caries removal methods in children: a randomized controlled clinical trial

A clinical and microbiological assessment of the efficacy of chemo-mechanical caries removal versus conventional caries removal methods in children: a randomized controlled clinical trial

Occurrence of Aggregatibacter actinomycetemcomitans and Its JP2 Genotype in a Cohort of 220 Western Australians with Unstable Periodontitis.

The main purpose of the present study was to investigate the carrier rate of Aggregatibacter actinomycetemcomitans and its JP2 genotype in a cohort of 200 Western Australians diagnosed with periodontitis. In this descriptive cross-sectional study, 220 consecutive patients with periodontitis, aged 18 years and older, were recruited to a specialist periodontal practice in Perth City. Every patient included in this study contributed three different intra-oral samples. Periodontal, radiographical, and microbiological assessments were performed. The samples were analysed using a polymerase chain reaction for the detection of Aggregatibacter actinomycetemcomitans and its JP2 genotype using the primers and conditions described previously. A Chi-square test and logistic regression analysis were performed to evaluate the results. The prevalence of Aggregatibacter actinomycetemcomitans was 28.18%. The carrier rates of A. actinomycetemcomitans in the unstimulated saliva, cheek swabs, and pooled subgingival plaque samples were 21.80%, 19.50%, and 17.70%, respectively. There was a significant correlation between the severe form of periodontitis (stage IV, grade C) and younger age (p = 0.004), positive family history of periodontitis (p < 0.001), oral hygiene method (p < 0.001), and irregular dental visit attendance (p < 0.001). The binary logistic regression analysis revealed that having severe periodontitis risk increased almost three times in those who were young (OR: 2.812) and came from a family with a history of periodontal disease (OR: 3.194). However, the risk of severe periodontitis was five times higher in those patients with tooth loss due to periodontal disease (OR: 5.071). The highly leukotoxic JP2 genotype of Aggregatibacter actinomycetemcomitans was not detected. This study of a Western Australian cohort confirmed the low presence of Aggregatibacter actinomycetemcomitans and the complete absence of its JP2 genotype. Young age, family history of periodontal disease, lack of flossing, irregular dental visits, and tooth loss due to periodontitis were identified as potential risk factors for periodontitis stage IV, grade C in this cohort.

Ecological conditions of vineyards and the polymorphism of Saccharomyces cerevisiae strains as a prerequisite of terroir identification

Aim. The aim of the study was to assess whether the ecological conditions for vineyards and the phylogenetic analysis of Saccharomyces cerevisiae wine yeast strains isolated from several locations in the Odesa and Mykolayiv regions could be used for terroir identification. Methods. The study employed microbiological, analytical, expedition, cartographic, and comparative assessment methods. Phylogenetic analysis was conducted using the MEGA software program, and VIN-CAD-UKR software was used for the vineyard cadastre and the ampelecological characteristics data management. Results. The study highlighted differences in the ecological conditions of vineyards in the Odesa and Mykolayiv regions and within the Tairovo and Izmail territorial communities in the Odesa region, focusing on soil and microclimatic characteristics. Saccharomyces cerevisiae strains isolated in 2012 and 2013, years with varying weather conditions in temperature and precipitation, were primarily clustered by the year of isolation. Two notable exceptions included a strain isolated from the Isabela variety belonging to a hybrid group (direct producer, contrary to other varieties, which mainly represent Vitis vinifera or its hybrids with Vitis riparia, Vitis amurensis, Vitis berlandieri) and a strain isolated from the Odesa Black variety inoculated at the beginning of fermentation with a commercial strain of wine yeast. The 2013 isolates, collected under conditions of higher precipitation and lower temperature in the first half of the growing season, showed a more differentiated clustering pattern, with two strains isolated from the Sukholymansky White variety forming a distinct cluster, while the rest grouped together, irrespective of the region, formed of isolation. Conclusions. Phylogenetic analysis of 64 strains of Saccharomyces cerevisiae isolated from 36 technical grape varieties based on the ITS1_5.8S_ITS2 nucleotide sequence demonstrated that the year of isolation (reflecting agroclimatic factors) was the primary influence on sample clustering. These factors, as components of the ecological conditions of terroir, form the foundation for terroir identification.

An Assessment of Drinking Water Quality in the Chief Albert Luthuli Local Municipality, South Africa: A Case Study of the Elukwatini Water Supply Scheme

This study analysed the water quality of 156 samples collected from 13 different points within the Chief Albert Luthuli Local Municipality between January and December 2021, focusing on compliance with the South African National Standard 241 (SANS 241). Microbiological assessments revealed widespread contamination, with heterotrophic plate counts (HPCs) exceeding the recommended range in nearly all samples. The median HPC levels were particularly concerning, with the untreated source (RE000) exhibiting a median of 2555 CFU/mL. Total coliforms and Escherichia coli were present at alarming levels, indicating significant faecal contamination; the highest total coliform count, 2420 CFU/100 mL, was recorded at RE000. Physically, while all samples complied with electrical conductivity standards (0–70 µS/cm), turbidity levels showed variability, with nine samples exceeding the acceptable threshold of 1 NTU. The highest turbidity, 7.55 NTU, was recorded at the untreated source (RE000). Chemically, pH levels fell within safe ranges (6.0–9.0), with all samples being compliant with standards. However, only one sample (E001) met the free chlorine standard of 0.3–0.6 mg/L, suggesting inadequate disinfection practices. The untreated source was classified as ‘Unsuitable for drinking’ (WQI = 207.27). These findings highlight the critical need for enhanced monitoring and remediation strategies to improve drinking water safety in the region.

Value of bronchial amylase level for predicting ventilator associated pneumonia in intubated adults: a systematic review and meta-analysis

BackgroundThe ability of bronchial amylase level for predicting ventilator associated pneumonia (VAP) has been extensively studied with conflicting results. This meta-analysis aimed to explore the value of bronchial amylase for predicting VAP in intubated adults.MethodsPubMed, Embase, and Cochrane Central Register of Controlled Trials were searched up to November 2023. The diagnostic odds ratio (DOR), sensitivity, and specificity were calculated. The summary receiver operating characteristic curve was estimated, and the area under the curve (AUROC) was calculated.ResultsOverall, six studies including 769 patients were included in this review, of whom 273 (36%) were developed VAP. The cutoff values of bronchial amylase level were ranged from 8.1 U/L to 4681.5U/L. Heterogeneity between studies was assessed with an overall Q = 1.99, I2 = 0, and P = 0.185, The pooled sensitivity and specificity for the overall population were 0.78 [95% confidence interval (CI) 0.67–0.86] and 0.75(95% CI 0.56–0.88) respectively. The DOR was 11(95% CI 3.0–40.0). The pooled AUROC was 0.83 (95%CI 0.80–0.86).ConclusionsThe bronchial amylase is a helpful marker for predicting VAP in intubated adults. However, it cannot be recommended as the single definitive test for VAP, but rather it must be interpreted in context with information from careful medical history, physical examination, and when feasible, microbiological assessment.

Beef Carcasses Aged at Mild Temperature to Improve Sustainability of Meat Production

Beef carcass aging, which enhances tenderness and flavor through proteolysis, is traditionally costly and slow, requiring long-term storage at temperatures near 0 °C. To reduce energy consumption, a new technique using moderate cooling room temperatures was tested. Six carcasses of Holstein bulls were used. From each carcass, two shoulders were processed in different ways: one was refrigerated at 8 °C (W), and after spraying with a solution with calcium chloride and sodium chloride, was coated with sodium alginate. The other shoulder was stored at 2 ± 1 °C as a cold control (C). After five days of aging, the shoulders were dissected, and two muscles (Caput longum triceps brachii and Supraspinatus) were subjected to physico-chemical analysis, microbiological safety assessment, and sensory testing. The remaining samples of both muscles were stored in domestic conditions for an additional 5 days at various temperatures (2, 4, 8 °C), where the same physic-chemical and sensory tests were conducted. The results showed that moderate aging temperature improved meat quality, significantly reducing the shear force (p = 0.001) and increasing sarcomere length, the myofibrillar fragmentation index, and sensory tenderness (p = 0.042, p = 0.039, and p = 0.027, respectively). However, domestic storage post-dissection should not exceed 4 °C to prevent rapid lipid oxidation, as observed at 8 °C for both muscles (p &lt; 0.001). Mild aging temperature maintained legal safety standards, enhanced certain meat qualities, and promoted enzymatic activity similar to traditional dry aging while reducing high energy consumption.

Soil microbiological assessment on diversified annual cropping systems in China

Recent studies have demonstrated that monocropping of flue-cured tobacco can lead to various issues, including nutrient deficiencies, accumulation of allelopathic substances, and disturbance in soil microbial flora. While diversification in cropping systems has proven effective in alleviating monocropping barriers, however, further exploration is needed to understand the potential microbial mechanisms involved in this process. In our study, we set five cropping systems (RR: rice monocropping; TR: tobacco-rice rotation over 20 years; TRA: tobacco-rice-astragalus rotation; TRW: tobacco-rice-wheat rotation; TRO: tobacco-rice-oilseed rape rotation) to explore the impact on crop yield and quality, soil chemical properties, and microbial diversity. The results showed that the yield and gross margin were significantly decreased. Following diversification in cropping systems, particularly after implementing the TRA treatment, the yield and gross margin increased by 27.35% and 38.67%, respectively, compared to the TR treatment. Additionally, the presence of tobacco in the soil resulted in acidification, reduced soil fertility, and suppression of soil microorganism diversity and metabolite abundance. With diversification in cropping systems, there was an increase in soil pH, carbon and nitrogen cycle enzyme activities, and the relative abundance of beneficial microorganisms (acidobacteria, nitrospirillum, and ascomycota) and soil metabolites. Diversification in cropping systems has the potential to increase crop biomass, soil fertility, and soil microbial environment. Our results suggest a scientific foundation for implementing effective nutrient management practices and rational crop rotation systems.

In Vitro Microscopical and Microbiological Assessment of the Sealing Ability of Calcium Silicate-Based Root Canal Sealers.

This in vitro study evaluated the sealing ability and microleakage of calcium silicate-based sealers compared to an epoxy resin-based sealer. One hundred twenty-five roots from anterior teeth were chemo-mechanically prepared and divided into four groups: AH Plus (AH), ProRoot MTA (PR), Medcem MTA (MC), and Total Fill BC Sealer/BC-coated gutta-percha (TF); n = 30. Confocal laser scanning microscopy was used to measure sealer penetration at three horizontal levels in 10 roots per group, while glucose leakage over 30 days was assessed in 20 roots. A lateral compaction technique was used for most groups, except for TF, which employed a single-cone method. Data were analyzed using Python with a Kruskal-Wallis test and Dunn's post hoc test. TF showed significantly greater penetration in the coronal and middle sections, while PR had the least penetration in the apical section. PR exhibited the highest canal circumference penetration, especially compared to MC and TF. Glucose leakage increased over time in all groups, with TF showing the highest permeability after 30 days. Overall, calcium silicate-based sealers PR, MC, and TF performed similarly to the epoxy resin standard AH, with all groups exhibiting decreasing penetration from coronal to apical and increased leakage over time.