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The performance of BACT/ALERT FA/FN Plus (France) blood culture containing a novel resin, DL (China) blood culture containing common resin, and adsorbent-free REDOX (USA) blood culture relying on dilution for antimicrobial neutralization at %peak serum concentration was evaluated by measuring the recovery of organisms and time to detection (TTD) in nine simulated microorganism-antimicrobial combination blood cultures. Significant differences were observed in the recovery rates among the aerobic media: 87.5% for BACT/ALERT media, 42.9% for DL media, and 12.5% for REDOX media. In contrast, no statistical difference was found in the TTD between FA Plus media and DL aerobic media. For the anaerobic media, the recovery rates were 91.4% for BACT/ALERT media, 2.9% for DL media, and 14.3% for REDOX media, with significant differences only between BACT/ALERT FN Plus media and the others. Among the seven main antimicrobial categories, only BACT/ALERT FA/FN Plus culture media demonstrated high recovery of microorganisms, with the exception of carbapenems. The DL culture media exhibited a relatively high recovery rate of microorganisms in the presence of piperacillin/tazobactam, levofloxacin, and gentamicin, but only in aerobic conditions. Conversely, REDOX media displayed microorganism recovery solely in the presence of gentamicin. BACT/ALERT FA/FN Plus culture media with novel resin showed absolute advantages over DL and REDOX culture media and can, therefore, be selectively applied in clinical settings when antimicrobials are used prior to blood collection. DL culture media, containing common resin, outperformed adsorbent-free dilution-based REDOX culture media, making it a viable backup option. There is a need to focus on improving the neutralization of carbapenems with current inefficiency in all three medias. IMPORTANCE: We present a study on performance comparison of three different commercial culture media for neutralization of antibiotic effects in simulated blood cultures. BACT/ALERT (FA Plus and FN Plus) culture media with novel resin showed absolute advantages over DL and REDOX culture media at %PSL concentration of antimicrobials.

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PURPOSE: Blood culture (BC) is the standard for diagnosing bloodstream infections. Available blood culture (BC) systems have been developed to shorten the time to detection (TTD) of positive BCs. This study aimed to evaluate the performance of the Mindray TDR automatic BC system by comparing it with the BacT/ALERT®3D system. METHODS: Sixteen reference strains and 14 clinical isolates were used. Serial dilutions were prepared from all bacterial and yeast colonies with a final concentration of 100 CFU/ml and 10 CFU/ml. The prepared solutions were simultaneously inoculated into the bottles of both systems and placed in blood culture devices. RESULTS: Three hundred and fifty-two (176 BacT/ALERT®3D and 176 Mindray TDR-X060) blood culture bottles were evaluated, 336 aerobic and 16 anaerobic. At both 10 CFU/ml and 100 CFU/ml dilution, there was no significant difference between the two systems in terms of mean detection times for all isolates (p = 0.965, p = 0.245). When evaluated according to the type of organism, the detection time of gram-positive bacteria at 10 CFU/ml dilution was significantly shorter in the BacT/ALERT system (p = 0.019), whereas detection time for yeasts was significantly shorter with the Mindray system (p = 0.047). The number of anaerobic bacteria was too small to draw statistical conclusions, but we observed a trend of shorter detection times in the Mindray TDR-X060 system. CONCLUSION: Two systems with similar operating principles showed different concentrations-dependent performances in terms of positivity detection times depending on the type of microorganism. Mindray TDR-X060 system has been found to be safe to use at high concentrations with this at lower concentrations further comparative studies are needed on the newly introduced Mindray system.

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BACKGROUND AND OBJECTIVE: Septic transfusion reactions due to bacterial contamination in platelet concentrates (PCs) are continually reported to hemovigilance (HV) programs. Worldwide, blood centers use different systems to avoid transfusion-associated bacterial sepsis in PCs. Herein, national HV data were gathered to compare bacterial protection systems and to assess the risk of bacterial contamination. MATERIALS AND METHODS: HV data with definite transfusion-associated bacterial sepsis in PCs were obtained from Australia, Canada, the United Kingdom (U. K.), and Switzerland between 2006 and 2016. These data were reviewed to evaluate bacterial protection systems including early small-volume (ESV), early large-volume (ELV), and delayed large-volume (DLV) bacterial culture screening and pathogen inactivation (PI) treatment. RESULTS: Implementation of DLV bacterial culture screening in the U. K. and PI treatment in Switzerland resulted in significant reductions (P < 0.05) in transfusion-associated bacterial sepsis for the period of 2011-2016 compared to the prior 4 years (2006-2010). Approximately 1.86 million DLV bacterial culture-screened PCs and 0.21 million PI-treated PCs were issued with no reported septic fatalities nor cases of life-threatening sepsis. In Australia, two life-threatening septic transfusion reactions (1.923 per million) were reported out of almost 1.04 million ELV bacterial culture-screened PCs, and no septic fatalities were reported. Meanwhile, in Canada, four life-threatening septic transfusion reactions (3.6/million) and one fatality (0.9/million) were observed in about 1.11 million ESV bacterial culture-screened PCs. CONCLUSION: DLV bacterial culture and PI treatment significantly reduced the incidence of septic reactions. The advantages and disadvantages of both systems merit further investigation before implementation.

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BACKGROUND: Microbial screening of platelet concentrates (PC) with automated culture methods is widely implemented to reduce septic transfusion reactions. Herein, detection of bacterial contamination in PC was compared between units prepared in plasma and a mix of plasma and platelet additive solution (PAS) and between the BACT/ALERT 3D and next generation BACT/ALERT VIRTUO systems. STUDY DESIGN/METHODS: Double apheresis units were split into single units, diluted in either PAS (PAS-PC) or plasma (plasma-PC), and tested for in vitro quality and sterility prior to spiking with ~30 CFU/unit of Staphylococcus epidermidis, Staphylococcus aureus, Serratia marcescens, and Klebsiella pneumoniae or ~10 CFU/mL of Cutibacterium acnes. Spiked PC were sampled for BACT/ALERT testing (36 and 48 h post-spiking) and colony counts (24, 36, and 48 h post-spiking). Times to detection (TtoD) and bacterial loads were compared between PC products and BACT/ALERT systems (N = 3). RESULTS: Bacterial growth was similar in plasma-PC and PAS-PC. No significant differences in TtoD were observed between plasma-PC and PAS-PC at the 36-h sampling time except for S. epidermidis which grew faster in plasma-PC and C. acnes which was detected earlier in PAS-PC (p < .05). Detection of facultative bacteria was 1.3-2.2 h sooner in VIRTUO compared with 3D (p < .05) while TtoD for C. acnes was not significantly different between the two systems. DISCUSSION: Comparable bacterial detection was observed in plasma-PC and PAS-PC with PC sampling performed at 36-h post blood collection. PC sampling at ≤36 h could result in faster detection of facultative pathogenic organisms with the VIRTUO system and improved PC safety.

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BACKGROUND: Neonatal sepsis is a major determinant of neonatal mortality. There is a scarcity of evidence-based guidelines for the duration of antibiotics in culture-positive sepsis. OBJECTIVES: The aim of this study was to compare the efficacy of 10- and 14-day antibiotic therapies in the management of culture-positive neonatal sepsis. METHODS: This randomized controlled trial was conducted in the neonatal intensive care unit of a tertiary care center among the neonates suffering from culture-positive sepsis (with signs of clinical remission on day 9 of antibiotic) between January 2023 and May 2023. Newborns with major congenital anomaly, deep-seated infections, multi-organ dysfunction, associated fungal infections/infection by multiple organisms and severe birth asphyxia were excluded. Two hundred and thirty-four newborns were randomized into two groups-study (received 10 days of antibiotics) and control (received 14 days of antibiotics). Treatment failure, hospital stay and adverse effects were compared between the two groups. p < 0.05 was taken as the limit of statistical significance. RESULTS: Median [interquartile range (IQR)] birth weight and gestational age of the study population (53.8% boys) were 2.424 kg (IQR: 2.183-2.695) and 37.3 weeks (IQR: 35.5-38.1), respectively. Acinetobacter was the most commonly isolated species (56, 23.9%). The baseline characteristics of both groups were almost similar. Treatment failure was similar in the study and control groups (3.8% vs. 1.7%, p = 0.40), with a shorter hospital stay [median (IQR): 14 (13-16) vs. 18 (17-19) days, p < 0.001]. CONCLUSION: Ten-day antibiotic therapy was comparable with 14-day antibiotic therapy in efficacy, with a shorter duration of hospital stay and without any significant increase in adverse effects.

Neonatal sepsis is a major cause of neonatal mortality in developing countries like India. Textbooks recommend 14-day antibiotic treatment for culture-positive neonatal sepsis. However, these guidelines are not strictly evidence based. Prolonged antibiotic treatment might be associated with drug resistance, secondary infections and organ damage. A shorter course of antibiotic, if found effective, would be beneficial especially in the resource-constrained settings like India. Hence, this study was undertaken to compare a shorter duration antibiotic treatment (10 days) with the conventional 14-day antibiotic therapy. Two hundred and thirty-four newborns with culture-positive sepsis were randomized into the study group (received 10 days of antibiotics) and the control group (received 14 days of antibiotics). Socio-demographic characters, clinical and laboratory features and bacteriological profile of both the groups were recorded. Both the groups were comparable in baseline features. Two-thirds of them were suffering from Gram-negative sepsis, Acinetobacter being the most commonly isolated organism. Incidence of treatment failure was similar in the study and control groups. Duration of hospital stay was significantly lower in the study group than in the control group. This observation was true irrespective of gestational age and type of organisms. There were no significant differences in adverse effects between the groups. However, there are certain limitations in the study, and hence, multi-centric research should be undertaken before making generalized recommendations of practising short duration of antibiotics.

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Peptidyl-prolyl isomerase-like 1 (PPIL1) is associated with the human spliceosome complex. However, its function in pre-mRNA splicing remains unclear. In this study, we show that Arabidopsis thaliana CYCLOPHILIN 18-2 (AtCYP18-2), a PPIL1 homolog, plays an essential role in heat tolerance by regulating pre-mRNA splicing. Under heat stress conditions, AtCYP18-2 expression was upregulated in mature plants and GFP-tagged AtCYP18-2 redistributed to nuclear and cytoplasmic puncta. We determined that AtCYP18-2 interacts with several spliceosome complex BACT components in nuclear puncta and is primarily associated with the small nuclear RNAs U5 and U6 in response to heat stress. The AtCYP18-2 loss-of-function allele cyp18-2 engineered by CRISPR/Cas9-mediated gene editing exhibited a hypersensitive phenotype to heat stress relative to the wild type. Moreover, global transcriptome profiling showed that the cyp18-2 mutation affects alternative splicing of heat stress-responsive genes under heat stress conditions, particularly intron retention (IR). The abundance of most intron-containing transcripts of a subset of genes essential for thermotolerance decreased in cyp18-2 compared to the wild type. Furthermore, the intron-containing transcripts of two heat stress-related genes, HEAT SHOCK PROTEIN 101 (HSP101) and HEAT SHOCK FACTOR A2 (HSFA2), produced functional proteins. HSP101-IR-GFP localization was responsive to heat stress, and HSFA2-III-IR interacted with HSF1 and HSP90.1 in plant cells. Our findings reveal that CYP18-2 functions as a splicing factor within the BACT spliceosome complex and is crucial for ensuring the production of adequate levels of alternatively spliced transcripts to enhance thermotolerance.

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Candida auris and other Candida species (C. albicans, C. glabrata, C. parapsilosis, C. tropicalis, and C. krusei) are important causes of bloodstream infection. Early or prolonged treatment with antifungal agents is often required. The inhibitory effect of antifungal agents in the patients' bloodstream may compromise the sensitivity of blood culture (BC) to diagnose and/or monitor patients with candidemia. Using a clinical BC simulation model, we compared antimicrobial drug-neutralizing BC media in BacT/Alert FA PLUS (FAP) or Bactec Plus Aerobic/F (PAF) bottles with non-neutralizing BC media in Bactec Mycosis IC/F (MICF) bottles to allow Candida growth in the presence of 100%, 50%, or 25% peak serum level (PSL) antifungal concentrations. In total, 117 organism/antifungal combinations were studied, and Candida growth was detected after incubating bottles into BacT/Alert VIRTUO or Bactec FX BC systems. Compared to control (without antifungal) bottles, both FAP and PAF bottles with 100% PSL antifungal concentrations allowed 100% recovery for C. auris, C. glabrata, and C. parapsilosis, whereas recovery was below 100% for C. albicans, C. krusei, and C. tropicalis. MICF bottles were less efficient at 100%, 50%, or 25% PSL antifungal concentrations, for all Candida species, except for C. auris. While azoles and amphotericin B did not hinder Candida growth in FAP or PAF bottles, echinocandins allowed C. auris, C. glabrata, and C. parapsilosis to grow in FAP, PAF, or MICF bottles. Overall, the maximum time to detection was 4.6 days. Taken together, our findings emphasize the reliability of BCs in patients undergoing antifungal treatment for candidemia. IMPORTANCE While echinocandins remain the preferred antifungal therapy for candidemia, bloodstream infections caused by C. auris, C. glabrata, or, at a lesser extent, C. parapsilosis may be difficult to treat with these antifungal agents. This is in view of the high propensity of the above-mentioned species to develop antifungal resistance or tolerance during treatment. Azoles and amphotericin B are possible alternatives. Thus, optimizing the recovery of Candida from BCs is important to exclude the likelihood of negative BCs for Candida species, owing to the inhibitory effect of antifungal agents present in the blood sample with which BCs are inoculated. Consistently, our results about the recovery of medically important Candida species (including C. auris) from simulated BCs in BacT/Alert FAP, Bactec PAF, or Bactec MICF bottles containing clinically relevant antifungal concentrations add support to this research topic, as well as to the use of BCs for monitoring the clinical and therapeutic course of candidemia.

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Theoretically, Aspergillus spp. grow in culture media, but frequently, blood cultures of patients with invasive Aspergillosis are negative, even if until now, the reasons are not clear. This aspect underlines the lack of a good strategy for the cultivation and isolation of Aspergillus spp. In order to develop a complete analytical method to detect Aspergillus in clinical and pharmaceutical samples, we investigated the growth performance of two blood culture systems versus the pharmacopeia standard method. At <72 h, all test systems showed comparable sensitivity, about 1−2 conidia. However, the subculture analysis showed a suboptimal recovery for the methods, despite the positive growth and the visualization of the "Aspergillus balls" in the culture media. To investigate this issue, we studied three different subculture approaches: (i) the use of a sterile subculture unit, (ii) the use of a sterile subculture unit and the collection of a larger aliquot (100 µL), following vigorous agitation of the vials, and (iii) to decapsulate the bottle, withdrawing and centrifuging the sample, and aliquot the pellet onto SDA plates. Our results showed that only the third procedure recovered Aspergillus from all positive culture bottles. This work confirmed that our strategy is a valid and faster method to culture and isolate Aspergillus spp. from blood culture bottles.

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The utility of anaerobic blood culture bottles remains controversial, especially for specimens from children. Data are limited on the inclusion of an anaerobic bottle as part of a blood culture "set" when using contemporary blood culture instruments and media. Here, we evaluated the clinical utility of anaerobic blood culture bottles (FN Plus) and aerobic bottles (FA Plus) for the BacT/Alert Virtuo blood culture system (bioMérieux). A total of 158,710 bottles collected between November 2018 and October 2019 were evaluated. There were 6,652 positive anaerobic bottles, of which 384 (5.8%) contained 403 obligate anaerobes. In patients <19 years old, there were 389 positive anaerobic bottles, with 15 (1.8%) containing 16 obligate anaerobes. If not for anaerobic bottles, all but 8 obligate anaerobes would have gone undetected. Furthermore, anaerobic bottles were advantageous for some facultative anaerobes. Staphylococcus aureus from anaerobic bottles demonstrated statistically significant increased recovery (1,992 anaerobic versus 1,901 aerobic bottles, P = 0.009) and faster mean time to positivity (1,138 versus 1,174 min, P = 0.027). Only 25 microorganisms had statistically significant improved recovery and/or faster time to positivity from aerobic versus anaerobic bottles, suggesting anaerobic bottles offer comparable growth for most species. Finally, if only an aerobic bottle had been collected, 2,027 fewer positive cultures would have been detected and 7,452 fewer isolates would have been reported, including cultures with S. aureus (413 isolates, 10.6% less), Pseudomonas aeruginosa (9 isolates, 3.1% less) and Escherichia coli (193 isolates, 14.0% less). Taken together, these findings support the practice of routinely including an anaerobic bottle for blood culture collection.

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The BacT/Alert system has been used for detecting the presence of bacteria in various clinical settings as well as in blood services, but it is associated with a relatively high incidence of false-positive results. We analyzed the results of our quality control sterility testing of blood products by BacT/Alert 3D to understand the mechanism of false-positive results. Anaerobic and aerobic bottles were inoculated with 10 mL of samples and cultured in BacT/Alert 3D for 10 days. Positive-reaction cases were classified as true positive if any bacterium was identified or false positive if the identification test had a negative result. The detection algorithm and the bottle graph pattern of the positive reaction cases were investigated. Among the 43,374 samples, 25 true positives (0.06%) and 29 false positives (0.07%) were observed. Although the detection algorithm of all true positives and 25 of 29 false positives was accelerating production of CO2, a steep rise in the bottle graph was observed only in the true positives, and it was not observed in either of the false positives. Four of 29 false positives were dependent on high baseline scatter reflections. Furthermore, evaluating the bottle graph pattern of Streptococcus pneumoniae, a bacterium known to autolyze, we confirmed that no viable bacterium was detected even if a steep rise was observed. In conclusion, the bottle graph pattern of positive reactions allows the differentiation between true positives and false positives. In case of a steep rise without bacterium detection, the bacterium might have autolyzed. Moreover, positive reactions with high baseline scatter reflections, despite immediate loading of bottles after sampling, are potentially false positive. IMPORTANCE In clinical settings, false-positive results are treated as positive until bacterial identification. It may result in the discarding of blood products in blood centers or affect clinical decisions in hospitals or testing facilities. Moreover, the management of these samples is usually time- and labor-consuming. The results of our study may help clinicians and laboratory staff in making a more precise evaluation of positive reactions in BacT/Alert.

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Microbiological diagnosis of osteoarticular infections (OAIs) is based on culture on several media. Experts recommend the use of liquid media, such as Schaedler broth, but many laboratories use blood culture media with automated detection instead for convenience. We aimed to evaluate the performance of culturing in BacT/Alert (bioMérieux) bottles for the microbiological diagnosis of OAI versus culturing in Schaedler broth. This prospective study was conducted on all osteoarticular specimens sent to the microbiology laboratories of the Versailles and Diaconesses Croix Saint-Simon hospitals between October 2016 and February 2017. Each sample was inoculated onto solid agar, into BacT/Alert bottles incubated for 14 days, and into a Schaedler broth incubated for 14 days with daily reading. The gold standard was defined as follow: OAI was diagnosed for a patient if at least two samples were positive for a nonskin microorganism and at least three for a cutaneous species. The times to detection were compared. A total of 1,616 specimens from 349 patients were collected. BacT/Alert bottles were significantly more sensitive than the Schaedler process for OAI diagnosis (114/135 OAI detected by BacT/Alert bottles; 91/135 OAI detected by Schaedler broth; +17.0% [95% confidence interval {CI}, 6.8%, 27.3%]; P = 0.0004). The time to detection was significantly shorter using BacT/Alert bottles (2.0 ± 2.2 days) than using Schaedler broth (4.6 ± 3.6 days, P < 0.0001). The culture of osteoarticular specimens in BacT/Alert bottles allows bacterial enrichment with an automated detection of positivity. Their use decreased detection time and increased sensitivity, making it a useful tool for the diagnosis of OAI that should be included among the recommended media. IMPORTANCE Microbiological diagnosis of OAI is based on culture on several media. French experts recommend the use of liquid media such as Schaedler broth, but many laboratories use blood culture media with automated detection in substitution because it is more convenient. We report here a prospective multicentric study evaluating the performance of culture in BacT/Alert (bioMérieux) bottles for microbiological diagnosis of OAI in comparison with culture in Schaedler broth. A total of 1,616 osteoarticular specimens from 349 patients were collected and inoculated onto agar, into BacT/Alert aerobic and anaerobic bottles, and into a Schaedler broth. BacT/Alert bottles were significantly more sensitive than the Schaedler process for OAI diagnosis (+17.0% [95% CI, 6.8%, 27.3%], P = 0.0004). The time to detection was significantly shorter for the BacT/Alert bottles (2.0 ± 2.2 days) than for Schaedler broth (4.6 ± 3.6 days, P < 0.0001). This study suggests that the use of BacT/Alert bottles should be recommended in microbiological diagnosis of OAI.

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Although Candida spp are aerobic microorganisms, some Candida strains, mainly Candida glabrata, can be recovered from anaerobic blood culture vials. We assessed the contribution of the anaerobic vials for the diagnosis of candidemia, especially for C. glabrata. We conducted a multicenter retrospective study including eight university or regional hospitals. A single episode of monomicrobial candidemia per patient was included from September 1st, 2016, to August 31st, 2019. The characteristics of all aerobic and anaerobic blood culture vials sampled within 2 h before and after the first positive blood culture vials were recorded (type of vials, result, and for positive vials time-to-positivity and Candida species). Overall, 509 episodes of candidemia were included. The main species were C. albicans (55.6%) followed by C. glabrata (17.1%), C. parapsilosis (4.9%), and C. tropicalis (4.5%). An anaerobic vial was positive in 76 (14.9%) of all episodes of which 56 (73.8%) were due to C. glabrata. The number of C. glabrata infections only positive in anaerobic vials was 1 (2.6%), 1 (11.1%), and 15 (37.5%) with the BACT/ALERT 3D the BACT/ALERT VIRTUO and the BACTEC FX instrument, respectively (P < 0.01). The initial positivity of an anaerobic vial was highly predictive of the isolation of C. glabrata with the BACTEC FX (sensitivity of 96.8%). C. glabrata time-to-positivity was shorter in anaerobic vial than aerobic vial with all instruments. Anaerobic blood culture vials improve the recovery of Candida spp mainly C. glabrata. This study could be completed by further analyses including mycological and pediatric vials. LAY SUMMARY: Although Candida spp are aerobic microorganisms, C. glabrata is able to grow in anaerobic conditions. In blood culture, the time-to-positivity of C. glabrata is shorter in anaerobic than aerobic vials. Only the anaerobic vial was positive in up to 15 (37.5%) C. glabrata bloodstream infections.

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BACKGROUND: Persistent cough and large amounts of purulent sputum affects many bronchiectasis patients. No studies have evaluated the efficacy and safety of bronchoscopic airway clearance therapy and bronchoalveolar lavage (B-ACT) for non-cystic fibrosis bronchiectasis patients with acute exacerbation. METHODS: A randomised controlled trial was conducted to explore the efficacy and safety of B-ACT among 189 bronchiectasis inpatients from February 1, 2018 to February 28, 2019. The primary outcome was the time to first acute exacerbation. Secondary outcomes included changes of health-related scores, length of hospital stay, hospitalization expenses and incidences of adverse events. FINDINGS: B-ACT therapy significantly prolonged the median days to first acute exacerbation when compared with control group (198 vs 168 days, HR 0·555 (0·322-0·958), p=0·012; effect size(r)= 0·94). Further analysis showed that B-ACT therapy was more beneficial for these patients with severe disease and greater symptoms. COPD Assessment Test (CAT) scores improved significantly on the third day (5·45 vs 4·85, 0·60 (0·09-1·11), p=0·023), and Leicester Cough Questionnaire (LCQ) scores improved obviously on the third and seventh days (1·53 vs 1·23, 0·30 (0·05-0·55), p=0·044; 1·66 vs 1·32, 0·34 (0·08-0·60), p=0·022; respectively) after B-ACT therapy. Adverse events associated with B-ACT were mostly transient and mild. Differences of the lengths of hospital stay and hospitalization expenses in both group was not significant. INTERPRETATION: B-ACT therapy significantly prolonged the time to first acute exacerbation after discharge, highlighting the importance of B-ACT therapy focused on symptom improvements in preventing exacerbation. FUNDING: National Natural Science Foundation of China. TRIAL REGISTRY: ClinicalTrials.gov; No.:NCT03643302; URL: www.clinicaltrials.gov.

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Introducción: Existen diferentes métodos de descontaminación de muestras pulmonares para el diagnóstico de micobacterias. El Programa Nacional de Control de Tuberculosis recomienda el método de Petroff modificado con solución salina, pero no existen evidencias documentadas que avalen este método. Objetivo: Evaluar el método de Petroff modificado con solución salina para el diagnóstico de micobacterias en el sistema Bact/Alert 3D. Métodos: Se realizó un estudio observacional analítico de pruebas diagnósticas utilizando 100 muestras pulmonares recibidas en el Laboratorio Nacional de Referencia e Investigaciones de Tuberculosis, Lepra y Micobacterias del Instituto Pedro Kourí, abril 2016 enero 2017. La muestra se dividió en 3 alícuotas y se descontaminaron mediante 3 métodos; luego se inocularon en los medios de cultivo sólido y líquido. Se compararon los resultados del cultivo en cuanto: tiempo de detección de crecimiento, tasa de contaminación, por ciento de positividad, además se calcularon indicadores de desempeño. Resultados: Al comparar el método Petroff modificado con solución salina con el Petroff modificado con solución fosfato en Löwenstein Jensen, el tiempo de detección de crecimiento, por ciento de positividad y la tasa de contaminación se comportaron de forma similar y la sensibilidad (93,75 por ciento), concordancia (96,47 por ciento) e índice de Youden (0,91) fueron elevadas. Al compararlo el Petroff modificado con solución salina con el N-Acetil-L-Cisteína, las variables no mostraron diferencias significativas y los Indicadores de Desempeño se comportaron por encima del 93 por ciento, para el medio sólido y líquido. Conclusiones: Los resultados avalan la continuidad del uso del Petroff modificado con solución salina como método de descontaminación de las muestras pulmonares en la red de laboratorios de Cuba y como alternativa en el pretratamiento de las muestras para el medio líquido (Bact/Alert 3D), además constituye un soporte para el Programa Nacional de Control de Tuberculosis(AU)

Introduction: There are different decontamination methods of pulmonary samples for the diagnosis of mycobacteria. The National Program for the Control of Tuberculosis recommends Petroff method modified with saline solution; but there are not documented evidences that endorse it. Objective: Assess Petroff method modified with saline solution for the diagnosis of mycobacteria in Bact / Alert 3D system. Methods: An observational analytic study of diagnostic tests was conducted; there were used 100 pulmonary samples received in the National Laboratory of References and Researches of Tuberculosis, Leprosy and Mycobacteria of Pedro Kourí Institute, from April 2016 to January 2017. The sample was divided in 3 aliquots and those were decontaminated using 3 methods; then, they were inoculated in the solid and liquid culture means. Cultures´ results were compared according to: growth's detection time, contamination rate, percent of positivity; in addition, performance indicators were calculated. Results: When comparing Petroff method modified with saline solution with Petroff method modified with phosphate solution in Löwenstein Jensen, the growth's detection time, the percent of positivity and the rate of contamination behaved similarly, and sensitivity (93,75percent), concordance (96,47percent) and Youden´s index (0,91) were high. When the Petroff method modified with saline solution was compared with N-Acetil-L- Cisteina, the variables did not show significative differences and the behaviour indicators were over 93percent for the solid and liquid mean. Conclusions: The results endorse the continuity of the use of Petroff method modified with saline solution as a decontamination method of pulmonary samples in the network of Cuban laboratories and as alternative to the pre-treatment of the samples for the liquid mean (Bact/Alert 3D); it also constitutes a support for the National Program for the Control of Tuberculosis(AU)

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The U.S. Food and Drug Administration (FDA) regulates manufacturing and testing of advanced therapeutic medicinal products (ATMPs) to ensure the safety of each product for human use. Gold-standard sterility testing (USP<71>) and alternative blood culture systems have major limitations for the detection of fungal contaminants. In this study, we evaluated the performance of iLYM (lactic acid-fermenting organisms, yeasts, and mold) medium (designed originally for the food and beverage industry) to assess its potential for use in the biopharmaceutical field for ATMP sterility testing. We conducted a parallel evaluation of four different test systems (USP<71>, BacT/Alert, Bactec, and Sabouraud dextrose agar [SDA] culture), three different bottle media formulations (iLYM, iFA Plus, and Myco/F Lytic), and two incubation temperatures (22.5°C and 32.5 to 35°C) using a diverse set of fungi (n = 51) isolated from NIH cleanroom environments and previous product contaminants. Additionally, we evaluated the effect of agitation versus delayed-entry static preincubation on test sensitivity and time to detection (TTD). Overall, delayed entry of bottles onto the BacT/Alert or Bactec instruments (with agitation) did not improve test performance. USP<71> and SDA culture continued to significantly outperform each automated culture condition alone. However, we show, for the first time, that a closed-system, dual-bottle combination of iLYM 22.5°C and iFA Plus 32.5°C can provide high fungal sensitivity, statistically comparable to USP<71>, when tested against a diverse range of environmental fungi. Our study fills a much-needed gap in biopharmaceutical testing and offers a favorable testing algorithm that maximizes bacterial and fungal test sensitivity while minimizing risk of product contamination associated with laboratory handling.

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Pellagra is characterized by "dermatitis - diarrhea - dementia - death". Various causes were discussed over the course of two centuries. The initial presumption was that the sun caused changes in exposed areas of the body. The "Zeïsts" blamed the maize (corn), which forms the main constituent in the diet of poor peoples, for being an insufficient nutrient and thus causing the pellagra in such indigent populations. The "Toxikozeïsts", however, regarded toxins produced by innocuous bacteria and fungi in unripe or in ripe but badly stored maize or in maize flour or in poorly baked maize bread as the cause of pellagra. Pellagra as an allergic disease was also discussed. Self-experiments of Goldberger's group in 1916 and finally Elvehjem's detection of niacin deficiency in maize in 1937 solved the problem.In the Austrian empire and (from 1867 on) in the Austro-Hungarian monarchy, pellagra was diagnosed and combated in the provinces of Küstenland, Tirolia and Bukovina and in Hungary. Originally believing in the noxiousness of maize in the poor population, extensive measures were planned and partially executed. Primarily measures for providing salubrious maize products were planned for the population, such as public bakeries and eating houses, kilns and storage houses for maize. For the treatment of pellagra patients, so-called pellagrosaria and auxiliary hospitals were established and the number of general practitioners was increased. It was also important to educate the population about preventing pellagra by consuming proper food. Pellagra funds to sustain the measures were established. In the provinces, pellagra commissions, chaired by the governor and consisting of twelve experts of the relevant medical branches, were appointed as an advisory and expert body.

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Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of the feed additive consisting of Bacillus licheniformis DSM 28710 (trade name: B-Act®) when used in feed for laying hens, minor poultry species for laying and for breeding purposes and ornamental birds. B. licheniformis is considered suitable for the qualified presumption of safety (QPS) approach to safety assessment. The identity of the active agent was established, and it does not harbour acquired antimicrobial resistance genes or has toxigenic potential. Following the QPS approach, B. licheniformis DSM 28710 is presumed safe for the target species, consumers and the environment. Since no concerns are expected from the other components of the additive, B-Act® is also considered safe for the target species, consumers and the environment. No conclusions can be drawn on the skin/eye irritation or skin sensitisation potential of the additive, but B-Act® is considered a respiratory sensitiser. B-Act® when supplemented at 1.6 × 109 CFU/kg complete feed has the potential to be efficacious in laying hens. Considering also that the efficacy of the product was already shown in chickens and turkeys for fattening, the Panel concludes that the additive has the potential to be efficacious in minor poultry species for laying, poultry species for breeding purposes and for ornamental birds at the same inclusion level. The conclusions on the compatibility of B-Act® with coccidiostats previously drawn apply to the current application provided that the maximum authorised concentrations of the coccidiostats for the target species are equal or lower than those for chickens.

RESUMEN

Effective detection of microbiological contaminations present in medicinal cellular products is a crucial step to ensure patients' safety. In recent decades, several rapid microbiological methods have been developed and validated, but variabilities linked to the use of different resources have led to discordant validation of methods and performance results. Considering this, while developing an in-house BacT/Alert-based method, we evaluated all of the materials used in its validation. Of particular importance, we noticed that the syringe gauge used to inject the samples into the bottles was crucial to obtain robust results. We chose to conduct a comparative test between the BacT/Alert system and the compendial method described in the European Pharmacopoeia, using five dilutions of nine reference microorganism strains and 21G or 27G needles. Our results confirmed that the BacT/Alert system is a valid and faster alternative method to assess sterility of clinical cell therapy products, and that the use of 27G needles increases its sensitivity to detect reference anaerobe microorganisms.

RESUMEN

PURPOSE: To evaluate the antimicrobial inactivation capabilities of BacT/ALERT (FA Plus and FN Plus) and BACTEC (Plus Aerobic/F and Lytic/10 Anaerobic/F) media. PATIENTS AND METHODS: The inactivation capabilities of the commercial blood culture media were compared using 21 microorganism-antimicrobial combinations in simulated adult blood cultures. RESULTS: BacT/ALERT culture media demonstrated higher detection rates than the BACTEC culture media. The recovery rates of the aerobic bottles were 74/115 (64.3%) for FA Plus bottles and 64/115 (55.7%) for BACTEC Aerobic Plus bottles. The BacT/ALERT FAN Plus culture media exhibited a shorter time to detection (TTD). The TTD of FA Plus media was 14.7 h, 4.85 h shorter than the BACTEC Aerobic media (19.55 h), while the TTDs of FN Plus media and BACTEC Anaerobic media were 16.8 h and 18.4 h, respectively. CONCLUSION: BacT/ALERT (FA Plus and FN Plus) media showed relative, but not absolute, advantages, as it had higher detection rates and shorter TTD and thus can be selectively applied to patients with prior use of antimicrobial agents before blood culture samples are taken.

RESUMEN

The evolution of homologous and functionally equivalent multiprotein assemblies is intriguing considering sequence divergence of constituent proteins. Here, we studied the implications of protein sequence divergence on the structure, dynamics and function of homologous yeast and human SF3b spliceosomal subcomplexes. Human and yeast SF3b comprise of 7 and 6 proteins respectively, with all yeast proteins homologous to their human counterparts at moderate sequence identity. SF3b6, an additional component in the human SF3b, interacts with the N-terminal extension of SF3b1 while the yeast homologue Hsh155 lacks the equivalent region. Through detailed homology studies, we show that SF3b6 is absent not only in yeast but in multiple lineages of eukaryotes implying that it is critical in specific organisms. We probed for the potential role of SF3b6 in the spliceosome assembled form through structural and flexibility analyses. By analysing normal modes derived from anisotropic network models of SF3b1, we demonstrate that when SF3b1 is bound to SF3b6, similarities in the magnitude of residue motions (0.86) and inter-residue correlated motions (0.94) with Hsh155 are significantly higher than when SF3b1 is considered in isolation (0.21 and 0.89 respectively). We observed that SF3b6 promotes functionally relevant 'open-to-close' transition in SF3b1 by enhancing concerted residue motions. Such motions are found to occur in the Hsh155 without SF3b6. The presence of SF3b6 influences motions of 16 residues that interact with U2 snRNA/branchpoint duplex and supports the participation of its interface residues in long-range communication in the SF3b1. These results advocate that SF3b6 potentially acts as an allosteric regulator of SF3b1 for BPS selection and might play a role in alternative splicing. Furthermore, we observe variability in the relative orientation of SF3b4 and in the local structure of three ß-propeller domains of SF3b3 with reference to their yeast counterparts. Such differences influence the inter-protein interactions of SF3b between these two organisms. Together, our findings highlight features of SF3b evolution and suggests that the human SF3b may have evolved sophisticated mechanisms to fine tune its molecular function.