Low Contamination Rate Research Articles

Microbial communities during the composting process of Agaricus subrufescens and their effects on mushroom agronomic and nutritional qualities.

Tunnel composting technology for preparing Agaricus subrufescens cultivation media can achieve a higher biological efficiency (BE) and a lower contamination rate (CR). However, this technology lacks in-depth and systematic study. In the present study, the changes in the microbiome and microbial metabolic functions were surveyed using metagenomic analysis. The physicochemical parameters, agronomic properties and nutritional qualities were also evaluated. Results showed that the contents of cellulose, hemicellulose and lignin dropped to 10.18, 11.58, 27.53%, respectively at the end of composting. The tunnel composting technology led to significant increases in crude protein content (32.56%) and crude fiber content (13.68%). Variations of physicochemical characteristics led to different successions of microbial communities. Bacteria manifested significantly higher abundance than fungi. Firmicutes, Actinobacteriota, Chloroffexi and Deinococcota were the predominant bacterial phyla. Ascomycota and Basidiomycota were the dominant fungal phyla in the thermophilic phase. Pseudonocardia, Truepera, and Thermopolyspora were positively correlated with the yield of A. subrufescens. In addition to TN, most of the physicochemical properties were significantly correlated with fungal communities in the thermophilic phase. The metabolisms of carbohydrate, amino acid and energy were the primary enrichment pathways. These findings deepen the understanding of microbial communities composition during the composting of A. subrufescens substrates. Moreover, this study provides a basis for improving tunnel composting technology.

Development of an Effective Sterilization Protocol for Plant Tissue Culture Studies in Superfruit Aronia [Aronia melanocarpa (Michaux) Elliot

Effective sterilization protocols are crucial for a successful tissue culture study in Aronia. These protocols directly influence contamination rates, shoot health, and root development. In this context, the aim of the study is to develop an effective sterilization protocol for plant tissue culture studies in Aronia [Aronia melanocarpa (Michaux) Elliot], commonly known as the "superfruit." In study, shoot tips of the Nero Aronia variety were used as material. The sterilized shoot tips were transferred to the respective plant tissue culture media in a randomized parcels trial pattern with three replicates, each containing three explants per replicate. Various concentrations and combinations of sterilizing agents, such as sodium hypochlorite (NaOCl), hydrogen peroxide (H2O2), mercuric chloride (HgCl2), and ethanol (C2H5OH), were evaluated to determine their effectiveness in maintaining tissue health and reducing contamination. A total of twelve protocols were developed, incorporating different concentrations of these chemicals. The results showed that the combination of 5% NaOCl and 3% H2O2 provided the lowest average contamination rate (5%) and the highest average number of healthy (uncontaminated) explants (9.00 piece), demonstrating the sterilization efficiency of this combination. On the other hand, protocols containing HgCl2, especially at higher concentrations, resulted in impaired root development. High ethanol concentrations also contributed to effective sterilization, with the combination of 7% NaOCl and 80% ethanol yielding a low contamination rate (8%) and preserving tissue health. This study emphasizes the need to balance sterilization protocols between effective contamination control and tissue viability. The findings are expected to benefit the improvement and development of tissue culture techniques for Aronia and similar species, providing a basis for further research on effective sterilization practices, which are currently limited in Aronia tissue culture.

Comparison of Power Ultrasound and NALC-NaOH Decontamination Methods for Stool Mycobacterial Culture: A Prospective Study.

Stool samples have been reported to be useful for the diagnosis of pulmonary tuberculosis (PTB), especially in patients who are unable to produce sputum. However, contamination limits the usefulness of stool specimens in mycobacterial culture. In this study, a novel decontamination method of power ultrasound (PU) was evaluated for mycobacterial isolation from suspected PTB cases. Stool samples (n = 650) were collected, and each sample was divided into approximately three equal groups. In addition to an AFB smear (Auramine O method), the stool samples were treated using different decontamination methods (NaOH-NALC vs. PU methods). The sensitivity (calculated against CRS) and contamination rates between the two methods were compared using McNemar's test. Of the 650 samples, 32 (4.92%) stool samples treated with the NaOH-NALC method were culture-positive, including Mycobacterium tuberculosis (M.TB; n = 21, 3.23%) and nontuberculous mycobacteria (NTM; n = 11, 1.69%). Sixty-one (9.38%) stool samples treated with the PU method were culture-positive, including M.TB (n = 37, 5.69%) and NTM (n = 24, 3.69%). Statistical analysis showed that a significant difference was found in the isolation rate of M.TB and NTM between the two methods (p < 0.05). Additionally, compared with the NALC-NaOH method (19.07%), stool samples treated with the PU method (13.23%) had a significantly lower contamination rate (p < 0.05). In conclusion, our findings suggest that the utilization of the PU method as a novel decontamination technique could significantly enhance the isolation rates of both NTM and M.TB when stool specimens are employed for culture. Compared to the NaOH-NALC method, this approach proves to be more effective in facilitating stool mycobacterial culture.

Construction of CS-SDAEM long-chain polysaccharide derivative on TA@CNTs coated PVDF membrane with effective oil-water emulsion purification and low contamination rate

Currently, the most effective way to improve the anti-fouling performance of water treatment separation membrane is to enhance the hydrophilicity of the membrane surface, but it can still cause contamination, leading to the occurrence of flux reduction. The construction of a strong hydration layer to resist wastewater contamination is still a challenging task. In this study, a defect-free hydration layer barrier was achieved by grafting chitosan polysaccharide derivatives (CS-SDAEM) on the membrane, which achieved in effective fouling prevention and low flux decline rate. A layer of tannic acid-coated carbon nanotubes (TA@CNTs) has been uniformly deposited on the commercial PVDF membrane so that the surface was rich in -COOH groups, providing sufficient reaction sites. These reactive groups facilitate the grafting of amphiphilic polymers onto the membrane. This modification strategy achieved in enhancing the antifouling performance. The modified membrane achieved low contamination rate with DR of 16.9 % for wastewater filtration, and the flux recovery rate was above 95 % with PWF of 1100 (L·m−2·h−1). The membrane had excellent anti-fouling performance, which provided a new route for the future development of water treatment membrane.

Back to Basics: Blood Culture Contamination Reduction Across a Multicenter Academic Health System

Background: Blood culture contamination is common in healthcare and contributes to diagnostic uncertainty, unnecessary treatments and follow-up testing, increased length of stay, higher rates of reportable healthcare-associated infections and events, over utilization of resources and staff including consultative care, and undue emotional stress to patients. The national benchmark for institutional blood culture contamination rates as recommended by The American Society for Microbiology (ASM) and the Clinical Laboratory Standards Institute (CLSI) is &lt; 3 %. Our institution’s overall rate was 8.9% with the highest burden being from our Emergency Department (ED) locations. We formed a multidisciplinary team aimed to reduce these rates through efforts centered around education and simplification of the collection process. Method: Working closely with and gathering feedback from nursing staff, nurse educators, and supply chain, we developed a blood culture collection kit that included all items necessary for blood culture collection thus eliminating the need for nurses to gather these items individually prior to collection. Additionally, simple step-by-step educational materials (Fig. 1) detailing the collection technique were provided. Education was presented at nursing huddles and skills fairs prior to kit roll-out. Blood culture kits were then stocked in place of individual blood culture collection bottles in all ED stock rooms in August 2022. Result: The 12-week pre-intervention period found 249 contamination events from 4265 total collections deriving a contamination rate of 5.8% across our health system’s four ED locations. During a 12-week post-intervention period following kit roll-out, 116 contamination events occurred from 3629 total collections deriving a contamination rate of 3.2% across our four ED locations. Given our results, we ultimately rolled this out to all units in all locations of our health system. When including all time from kit rollout to present (August 2022 to November 2023, 16 months), there were 1077 contamination events from 43379 total collections deriving an overall contamination rate of 2.5%. When compared to the 16 months prior to the kit rollout (April 2021 to July 2022) there were 1803 contamination events in 49335 total collections (3.7% contamination rate) deriving an overall percent reduction of 32.1%. Conclusion: We were able to decrease our health system’s blood culture contamination rate through simple interventions aimed at reducing the mental burden on nursing staff by developing a blood culture collection kit and educational materials. Since implementation of the kits, we have continued to maintain lower contamination rates as evident by our 16 month follow up period.

Assessing the performance of methods for central statistical monitoring of a binary or continuous outcome in multi-center trials: A simulation study

BackgroundQuality study monitoring is fundamental to patient safety and data integrity. Regulators and industry consortia have increasingly advocated for risk-based monitoring (RBM) and central statistical monitoring (CSM) for more effective and efficient monitoring. Assessing which statistical methods underpin these approaches can best identify unusual data patterns in multi-center clinical trials that may be driven by potential systematic errors is important. MethodsWe assessed various CSM techniques, including cross-tests, fixed-effects, mixed-effects, and finite mixture models, across scenarios with different sample sizes, contamination rates, and overdispersion via simulation. Our evaluation utilized threshold-independent metrics such as the area under the curve (AUC) and average precision (AP), offering a fuller picture of CSM performance. ResultsAll CSM methods showed consistent characteristics across center sizes or overdispersion. The adaptive finite mixture model outperformed others in AUC and AP, especially at 30% contamination, upholding high specificity unless converging to a single-component model due to low contamination or deviation. The mixed-effects model performed well at lower contamination rates. However, it became conservative in specificity and exhibited declined performance for binary outcomes under high deviation. Cross-tests and fixed-effects methods underperformed, especially when deviation increased. ConclusionOur evaluation explored the merits and drawbacks of multiple CSM methods, and found that relying on sensitivity and specificity alone is likely insufficient to fully measure predictive performance. The finite mixture method demonstrated more consistent performance across scenarios by mitigating the influence of outliers. In practice, considering the study-specific costs of false positives/negatives with available resources for monitoring is important.

Umbilical cord blood culture for early onset sepsis in preterm infants.

Umbilical cord blood culture (UCBC) may have a diagnostic utility for early onset sepsis (EOS) detection in preterm infants. It may prevent sampling the newborn and collect a higher volume of blood for pathogenic identification. Retrospective analysis at a tertiary care center in Canada of preterm infants ≤ 34 0/7 weeks' gestation with UCBC taken at birth. Of 505 admitted infants, 195 had UCBC. 170 UCBCs were negative; 44 of these had also negative neonatal blood culture (NBC). No infants with negative UCBC showed EOS symptoms in the first week of life. 25 UCBCs were positive: 18 were contaminants (all with negative NBC) and 7 were confirmed as EOS. 18 infants with UCBC contaminants remained asymptomatic. 7 EOS cases were identified, with varying bacteriological profiles; 5 displayed sepsis symptoms while 2 were asymptomatic. Risk of EOS increased with prolonged rupture of membranes. UCBC effectively detected EOS establishing it as a method with possibly better diagnostic performance than NBC in high-risk neonates. Further studies are needed to improve UCBC technique and lower contamination rates. Umbilical cord blood culture has a higher bacterial identification rate than peripheral venous blood culture for the early identification of early-onset sepsis in preterm infants. Umbilical cord blood cultures that showed no growth were reliable predictors of not developing early onset sepsis. Umbilical cord blood culture should be considered as part of the evaluation for early onset sepsis in the preterm infants.

Assessment of heavy metals and fungi contamination of spices available in Saudi Arabian food cuisines

The study investigates the elemental composition and fungal contamination of commonly utilized spices and herbs, namely Turmeric, Cloves, Black pepper, Latency/cumin, Ring/legume, Cinnamon, Coriander, Ginger, Indian saffron, Fenugreek, Fennel flower, Aniseed, and Cayenne pepper. The presence of minerals and poisons elements, including zinc (Zn), iron (Fe), chromium (Cr), manganese (Mn), copper (Cu), nickel (Ni), cadmium (Cd), and lead (Pb), was examined. The concentration of the poisonous elements ranged from 44.1 ± 1.3 to 231±41 µgg−1 for Fe, 3.8 ± 5.9 to 17.3 ± 3.1 µgg−1 for Zn, 1.3 ± 0.2 to 9.3 ± 0.4 µgg−1 for Cu, 10.4 ± 1.1 µgg−1 for Mn, and 219±2.1 µgg−1 for Pb; Cd was below the level of detection. The study also assessed fungal contamination, revealing black pepper as the most contaminated sample (87.6 %), followed by saffron (76.2 %), Cayenne pepper (72.1 %), Coriander (65.0 %), and cumin (64.4 %). Conversely, fenugreek (52.5 %) and cinnamon (51.6 %) exhibited lower contamination rates. Aspergillus flavus was predominant in white pepper (70.0 %) and black pepper (34.0 %), while ginger showed a diverse range of fungal species, including A. niger, A. flavus, and Rhizopus stolonifera (50 %). Notably, cinnamon was found highly contaminated with Aspergillus flavus (40 %), Aspergillus niger (40 %), and Rhizopus stolonifera (40 %), while legumes were contaminated with Aspergillus niger (40 %), Penicillium arenicola (40 %), and Penicillium oxalicum (40 %). This study highlights potential health risks associated with spice consumption, particularly in large quantities, due to mycotoxin contamination. The findings emphasize the importance of monitoring and implementing stringent quality control measures in the spice industry to ensure food safety and mitigate health hazards associated with elemental and fungal contamination. By combining scientific rigor with a focus on local context, this research strives to make a meaningful impact on public health, culinary traditions, and the broader global conversation on food safety.

Assessing the Profile of Glyphosate Residues in Maize Grains Sold in the Federal Capital Territory Abuja, Nigeria

The profile of glyphosate residues in maize grains sold in the Federal Capital Territory Abuja (FCT), Nigeria was assessed. Methods Twenty-six maize grains samples of yellow and white morphotypes were collected from some selected markets within the FCT, Abuja. Analytical methods on the pulverized maize grains included solvent extraction using (acetonitrile/water (55:45), clean-up of pesticide residues and their quantification by HPLC/UV as described by AOAC - QuEChERS method. Results The results showed that the mean concentration of glyphosate in the maize grains ranged from 0 to 24.30 ± 0.002 mgkg_1 with a mean glyphosate concentration of 3.474 mgkg-1 was detected. Four samples representing 17.86% of the samples collected violated WHO/FAO CODEX standard of 5.0 mgkg-1 while values recorded for Acceptable Daily Intake (ADI) for all the samples were within an acceptable limit of 0 - 1 mgkg-1. Heath risk index values were &lt;1 suggesting that the consumer populations were not at risk. Conclusion The high profile of glyphosate residue in maize grains from Gwagwalada Area Council of the FCT is of great concern and needed to be further investigated HIGHLIGHTS Maize grains had a low glyphosate residue contamination rate of 96.15% in the FCT, Nigeria. The concentration rate of glyphosate residue in the maize grains range was 0 - 24.3mg/kg Yellow maize grains from Gwagwalada Area Councils had the highest mean concentration of glyphosate residue. Four samples i.e. 15.38% of the maize grains violated the CODEX Maximum Residual limit. The Health Index (HI) for all the maize grains was ˂ 1 and signified no associated risk

Rapid high-throughput processing of tissue samples for microbiological diagnosis of periprosthetic joint infections using bead-beating homogenization.

Enrichment of periprosthetic tissue samples in blood culture bottles (BCBs) for microbiological diagnosis of periprosthetic joint infections (PJI) is more reliable than the use of an enrichment broth. Nevertheless, the extremely time-consuming homogenization of the samples for BCB processing has so far limited its use, especially in high-throughput settings. We aimed to establish a highly scalable homogenization process of tissue samples for long-term incubation in BCBs. A protocol for homogenization of tissue samples using bead beating was established and validated. In a second step, the use of the homogenate for enrichment in BCBs was compared to the use of thioglycolate broth (TB) in terms of diagnostic accuracy using clinical tissue samples from 150 patients with suspected PJI. Among 150 analyzed samples, 35 samples met the microbiological criteria for PJI. Using BCB, 32 of 35 (91.4%) PJI were detected compared to 30 of 35 (85.7%) by TB. The use of BCB had a lower secondary contamination rate (2/115; 1.7% vs 4/115; 3.5%) but the trend was not significant due to low numbers of samples (P = 0.39). The time to process a batch of 12 samples using the established homogenization method was 23 ± 5 min (n = 10 batches). We established and validated a homogenization workflow that achieves the highest sensitivity in the microbiological diagnostic of PJI. The enrichment of the tissue homogenate in BCBs showed equally good results as the use of enrichment broth and allows semi-automated high-throughput processing while demonstrating lower contamination rates in our study.

Effectiveness of Multimodal Intervention to Improve Blood Culture Collection in a Tertiary Care Hospital.

Introduction and methods Blood culturing has become one of the backbone investigations for septicemia, fever of unknown origin, etc. This study was conducted to test the effect of multimodal interventions on the practical skills of healthcareworkers (HCWs), raise awareness regarding the importance of aseptic blood culture collection practices, and increase compliance with the specific steps to be followed. Hence, this current interventional study was aimed at comparing the rate of isolation of contaminants grown among the blood culture specimens, assessing the knowledge, attitude, and practice (KAP) of HCWscollecting the blood culture specimen on various aspects of sample collection, educating the nursing staff regarding blood sample collection using a structured, pre-formed checklist, and emphasizing best practices for blood culture collection. All of the study's objectives were successfully met within the time frame specified. Using a pre-formed checklist and a Google form for KAP analysis eased the calculation. Results On analysis, the blood culture contamination rate in the pre-interventional phase dropped drastically from 6.16% to 3.03% in the post-interventional phase. The educational sessions conducted are a paramount reason for the reduction in the contamination rate. The HCWs were the least compliant towards the eighth step in the checklist (regarding palpation of skin); however, that too increased from 66.93% and 64.51% to a whopping 82.25% and 83.06%, respectively, with a chi-squarevalue of 0.03 and a p-valueof 0.85 (not significant). Conclusion Implementation of interventional studies as an audit like this in tertiary care hospitals can result in a significant reduction in blood culture contamination rates and can also improve the compliance of HCWs with blood culture protocols. This, in turn, can overall improve the effectiveness of blood culture (BC) testing and reduce mortality and morbidity in tertiary care hospitals. Further research can be conducted to brainstorm more methods to increase the compliance of HCWs. Better monitoring strategies can also be set to ensure low contamination rates. Additionally, some other methods can be derived to locate the source of contamination within the hospital environment and thus eliminate it. Similar interventions can be conducted for a longer duration of time to further reduce the blood culture contamination rate below 3% (as per the recommendations).

Fungal contamination of the water distribution system of a tertiary hospital water supply system in a resource-limited setting.

Fungal contamination of hospital water distribution systems has been implicated in outbreaks of healthcare-associated infections. To evaluate the prevalence of fungi in the water distribution system of a tertiary hospital in Nigeria. This was a descriptive cross-sectional study. Swabs and water samples were collected from taps and faucets in the hospital categorized into low (Accidents and Emergency Unit, Children Emergency Unit, Acute Stroke Unit and the 24 in-patient hospital wards) and high-risk (Renal Dialysis Unit, Central Sterile Services Department, Theatres and Intensive Care Units (ICUs)) units based on the vulnerability of patients being managed there. The membrane filtration method for water analysis was used. Where possible, isolates cultured were identified to species level. In total, 105 water and 49 swab samples were collected for analysis. All analysed water samples grew fungi. A total of 289 (high-risk; n = 178; low-risk; n = 111) and 76 fungi isolates were recorded from water and swab samples, respectively, with 31 different species identified. Aspergillus was the most predominant genus with five different species: Aspergillus niger (9.9%), terreus (4.4%), flavus (3.3%), fumigatus (8.8%) and versicolor (2.20%) isolated. Twenty-five and 18 species of fungi were identified in the low and high-risk units, respectively. The labour ward (n = 46; 25.8%) and modular theatre (n = 47; 42.3%) were the most contaminated units. Cladosporium spp. and Paecilomyces spp. were the most frequently isolated fungi in the low and high-risk units, respectively. The dialysis centre (n = 9; 8.1%) and renal transplant theatre (n = 7; 6.31%) had the lowest contamination rates in the high-risk units. Aspergillus niger, Cephalosporium curtipes, Penicillium chrysogenum and Penicillium glabrum were each identified in 4/6 units from which swabs were taken. The facility had no documented protocol for its water safety and quality. Our data reveal a high rate of contamination of hospital water sources by fungi, some of which are known to cause life-threatening infections. For better water treatment and water tank cleaning and disinfection, a standard protocol is advised. Ensuring that the water distribution systems in hospital settings are free of fungal contaminants is important to prevent the possibility of waterborne mycosis outbreaks.

Gümüş Nitrat ve Ön Soğuk Uygulamalarının Çilek Anter Kültüründe Kallus Oluşumuna Etkileri

Strawberry (Fragaria x ananassa Duch.) which is one of the widely grown berry species in the world has economic and commercial importance. In commercial strawberry varieties, in order to increase yield and quality, it is necessary to obtain starting materials that are resistant/tolerant to biotic and abiotic stress factors. Biotechnological methods have an important place in strawberry breeding studies due to the long and costly process of classical breeding methods, the genetic expansion of seed production, high ploidy level and strong heterozygosity. Haploid plant production is an efficient breeding method that has been successfully applied to most plant species. However, due to the lack of sufficient haploid studies on strawberry and the fact that a specific protocol for this species has not yet been developed the necessary progress has not been made in this regard. In this study, the effectiveness of some factors determine the success in anther culture which has a significant place in obtaining haploid strawberries was investigated. For this reason, first, different sodium hypochlorite doses (NaOCl; 1%, 2%, 3%) and application durations (10, 15, 20 min) were used to determine the appropriate method for sterilisation, then cold pre-treatments (24, 36, 48, 72 hours at +4 °C) and different silver nitrate doses (AgNO3; 10, 20, 30, 40 mg l-1) were employed for callus induction in Festival strawberry variety. At the conclusion of the study it was observed that the lowest contamination rate (1%) was obtained by soaking in 1% sodium hypochlorite solution for 10 minutes. Cold pre-treatment of flower buds at +4 °C for 36 hours produced the highest callus induction rate (96%). The evaluation of the effect of AgNO3 application at different doses on the callus induction rate revealed that the highest callus induction (82%) was obtained from 20 mg l-1 AgNO3 dosage. This study showed that anther culture practices in strawberry can be improved by using cold pre-treatment, appropriate sterilization method and silver nitrate addition to the medium.

Dominance of Diarrheagenic E. coli Virulent Types in Integrated Crop–Livestock Farms and Their Antibiotic Resistance Patterns

Microbial ecology on integrated crop–livestock farms (ICLFs) can impact food safety through pathogen transfer between animals and crops. Recent reports of pathogen-contaminated products sold in local organic retail, roadside, and farmers markets highlight the need for assessment of the ecological patterns of bacterial pathogens. This study investigated the prevalence and antibiotic resistance of the virulent type of diarrheagenic E. coli in ICLFs. Over two years, 2973 samples from ICLFs and markets in Maryland and Washington DC were analyzed. Diarrheagenic E. coli was found in 4.30% (128/2973) of collected samples, with a higher isolation rate in environmental (4.42%, 59/1332) and produce (4.20%, 69/1641) samples. Overall, livestock bedding materials had the highest prevalence (8.51%, 4/47). Post-harvest produce exhibited a lower contamination rate of 1.32% (10/756), whereas pre-harvest produce had a higher incidence with 6.67% contamination (59/885), indicating the presence of E. coli. Alarmingly, 92.30% (72/78) of pathogenic E. coli isolates were resistant to common antibiotics. The findings highlight potential risks associated with integrated farming practices and emphasize the importance of safe harvesting and post-harvesting measures, particularly in the context of the growing popularity of local integrated farming. Implementing precautions at on-farm and market levels is crucial to mitigate the risk of antibiotic-resistant E. coli-related enteric illnesses, safeguarding both consumers and the integrity of integrated farming systems.

Optimização do crescimento in vitro e composição de óleos essenciais de cultivares de manjericão

Abstract The objective of this work was to evaluate the effect of the use of the Murashige &amp; Skook (MS) and Linsmaer &amp; Skoog (LS) media and of filter caps on culture flasks on the morphological and physiological characteristics of basil cultivars in vitro, as well as to determine the composition of the essential oil of plants acclimatized in pots. For the evaluation of the cultivation media, cultivars Anise, Cinnamon, Grecco a Palla, and Italian Large Leaf were used. The Anise, Cinnamon, Italian Large Leaf, and Maria Bonita cultivars were used for the evaluation of the use of filter caps. The composition of the essential oils of cultivars Anise, Cinnamon, and Italian Large Leaf was also evaluated. The basil seedlings showed a higher aerial-part dry mass and a lower hyperhydricity rate when grown in the MS medium. The flasks without filter caps produced seedlings with lower contamination rates. When acclimatized in pots, cultivars Limoncino and Anise presented the tallest plants with the largest crown diameters. In the composition of essential oils, methyl cinnamate and linalool stood out in cultivar Cinnamon, methyl chavicol in Anise, and linalool in Italian Large Leaf. In the in vitro cultivation, the evaluated cultivars present a higher aerial-part production in the MS medium and a lower contamination without the use of filters, whereas, in the pots, the composition of essential oils varies according to the cultivar.

Review of Blood Cultures Taken From Arterial Lines in James Cook University Hospital: Contamination Analysis And Comparison With Venous Samples

BACKGROUND: Blood cultures are crucial diagnostic tools for identifying and treating bloodstream infections. Traditionally, venous blood is the preferred source for sample acquisition, but arterial lines offer an alternative. However, concerns regarding contamination and diagnostic accuracy have been raised, questioning the reliability of arterial line blood cultures. This study aimed to evaluate the contamination rates of arterial line blood cultures at James-Cook University Hospital (JCUH), UK and compare them with venous samples to understand their clinical utility better. METHODS: A comprehensive retrospective review analysed 17,643 blood culture samples collected between September 2022 and March 2023 at JCUH. Among these, 109 arterial line blood cultures and 785 venous peripheral adult samples were included for data analysis. Contamination rates were calculated as the number of positive blood cultures with contaminants per total positive samples (arterial or venous). The incidence of contamination was defined as the number of total blood cultures reported with contaminants per total samples (arterial or venous). No discrimination was made based on the number of contaminants found. Clinical information accompanying the blood cultures, such as the specification of arterial lines as 'new' samples, was also considered. RESULTS: The overall contamination rate at JCUH was found to be 4.99%. Specifically, the contamination rate for venous samples was 49.26%, while arterial samples had a higher contamination rate of 56.52%. The incidence of contamination from arterial samples was 11.92%, significantly higher than the incidence rate for venous samples at 3.18%. Most arterial samples were requested from intensive care units (ICUs) and highly dependent wards (HDUs), indicating potential areas for targeted interventions to improve blood culture collection practices. CONCLUSION: Arterial blood cultures demonstrated higher contamination rates compared to venous samples, raising concerns about their reliability. Contamination in arterial samples, particularly when collected from critically ill patients in ICUs and HDUs, can lead to inappropriate use of antibiotics, delayed, or missed diagnosis, and suboptimal patient outcomes. The study recommends targeted interventions to improve arterial blood culture collection practices and further training for healthcare workers involved in arterial line care. Encouraging the use of only 'new' arterial lines and implementing standardized protocols can help reduce contamination rates. Furthermore, the study identified certain limitations, such as potential human errors in data analysis and the need for a larger dataset of arterial line cultures. Extending the analysis to compare different sample sources like CVCs, Hickman lines, and central lines could provide a more comprehensive understanding of contamination rates across various culture collection methods. In conclusion, venous samples showed higher clinical favourability with a lower contamination rate, providing increased dependability for accurate diagnosis and management. Although some studies have not shown clear superiority of arterial samples over venous samples, this analysis highlights considerable differences in contamination rates, suggesting a potential inferiority of arterial blood culture samples. While efforts can be made to optimize the consistency of arterial samples and reduce contamination rates, their use should be approached with caution. Implementing the recommended measures is essential for accurate diagnosis, improved patient outcomes, and effective antibiotic management in clinical practice.

Transvaginal natural orifice transluminal endoscopic surgery-assisted versus transumbilical laparoendoscopic single-site ovarian cystectomy for ovarian mature cystic teratoma. A randomized controlled trial.

Transvaginal natural orifice transluminal endoscopic surgery (vNOTES) and transumbilical laparoendoscopic single-site surgery (LESS) have shown the prospection as minimally invasive procedures. Here we aimed to compare ovarian cystectomy assisted by vNOTES and by LESS for ovarian mature cystic teratoma (OMCT). A total of 81 premenopausal women with OMCT were randomized to undergo ovarian cystectomy assisted by either vNOTES (n = 41) or LESS (n = 40). The main outcome was the operative time. Secondary outcomes included the length of hospital stay, visual analog scale (VAS) pain scores, abdominal contamination by teratoma contents, and intraoperative and postoperative complications. There were no intergroup differences in age, body mass index, tumor size, or bilaterality of tumor. The operative time for the vNOTES group was significantly shorter than that for the LESS group (68.41 ± 20.92 min vs 85.05 ± 32.94 min, p = 0.008). The highest VAS pain score 24 hours postoperatively was 1.21 ± 0.48 in the vNOTES group and 2.43 ± 0.57 in the LESS group (p < 0.001). Twenty-four of the 40 patients in the LESS group experienced teratoma rupture intraoperatively, leading to abdominal contamination by the teratoma content, while 5 abdominal contamination was observed in the vNOTES group （p = 0.005. No significant differences between the two groups were observed in the other outcomes. vNOTES assisted ovarian cystectomy has short operative time, fast recovery, no scarring, less pain, and low rate of abdominal contamination. Consequently, vNOTES might be superior to LESS for treating OMCTs.

The Usability of Extracts of Walnut Green Outer Shell for In vitro Surface Sterilization of Rosehip (Rosa canina L.) Plant

In this study, it was aimed to determine the efficiency ratios of extracts obtained from walnut outer green shell at different concentrations in order to provide surface sterilization in in vitro propagation of rosehip plant. Axillary buds taken in June were used as explants. After surface sterilization of the explants with walnut outer shell extract, they were cultured in MS0 nutrient medium. The lowest contamination rate on the 5th and 7th days was observed in the control and 20K groups. In addition, the highest number of shoots per explant was obtained in the 20K group. Uncontaminated explants were subcultured to MS0 medium containing 1.0 mg /L IBA + 1.0 mg /L BAP and 1.0 mg/L BAP + 1.0 mg/L NAA at the end of the 7th day. Rooting was not observed in the explants due to browning. In the in vitro propagation of plants, extract (20K) obtained from oven-dried walnut shell can be used instead of chemical sterilant.

Detecting changes in the performance of a clinical machine learning tool over time

Excessive use of blood cultures (BCs) in Emergency Departments (EDs) results in low yields and high contamination rates, associated with increased antibiotic use and unnecessary diagnostics. Our team previously developed and validated a machine learning model to predict BC outcomes and enhance diagnostic stewardship. While the model showed promising initial results, concerns over performance drift due to evolving patient demographics, clinical practices, and outcome rates warrant continual monitoring and evaluation of such models. A real-time evaluation of the model's performance was conducted between October 2021 and September 2022. The model was integrated into Amsterdam UMC's Electronic Health Record system, predicting BC outcomes for all adult patients with BC draws in real time. The model's performance was assessed monthly using metrics including the Area Under the Curve (AUC), Area Under the Precision-Recall Curve (AUPRC), and Brier scores. Statistical Process Control (SPC) charts were used to monitor variation over time. Across 3.035 unique adult patient visits, the model achieved an average AUC of 0.78, AUPRC of 0.41, and a Brier score of 0.10 for predicting the outcome of BCs drawn in the ED. While specific population characteristics changed over time, no statistical points outside the statistical control range were detected in the AUC, AUPRC, and Brier scores, indicating stable model performance. The average BC positivity rate during the study period was 13.4%. Despite significant changes in clinical practice, our BC stewardship tool exhibited stable performance, suggesting its robustness to changing environments. Using SPC charts for various metrics enables simple and effective monitoring of potential performance drift. The assessment of the variation of outcome rates and population changes may guide the specific interventions, such as intercept correction or recalibration, that may be needed to maintain a stable model performance over time. This study suggested no need to recalibrate or correct our BC stewardship tool. No funding to disclose.

Headspace stir-bar sorptive extraction combined with gas chromatography-mass spectrometry for trace analysis of volatile organic compounds in Schisandra chinensis Baillon (omija).

Analyzing volatile organic compounds (VOCs) in food is crucial but challenging. Schisandra chinensis Baillon (omija) is an herbal plant with various functional health activities. Previous VOC analyses focused on S. chinensis fruit but not its leaves. Therefore, VOCs in S. chinensis fruit and leaves were analyzed using headspace stir-bar sorptive extraction (HS-SBSE)-GC-MS, and optimal conditions were established. Various factors, such as the sample preparation method, twister stir-bar type, sample amount, extraction temperature, and extraction time, expected to affect extraction were carefully optimized. Under the optimal conditions, 35 and 40 VOCs were identified in S. chinensis fruit and leaves, respectively. This HS-SBSE method is capable of rapid analysis and a low contamination rate without requiring organic solvents. These findings provide practical guidelines for HS-SBSE applications in various food matrices by providing analytical methods for VOC detection.