Phenotypic and genotypic determination of resistance to common disinfectants among strains of Acinetobacter baumannii producing and non-producing biofilm isolated from Iran.

BACKGROUND: Nosocomial infections are a global problem in hospitals all around the world. It is considered a major health problem, especially in developing countries. The increase in the patient's stay in hospitals has increased the mortality rate, and consequently, the costs drastically increase. The main purpose of using disinfectants in the hospital environment is to reduce the risk of nosocomial infections. Ethylene diamine tetra acetic acid (EDTA) causes lysis and increases susceptibility to antimicrobial agents in the planktonic form of bacteria. This substance affects the permeability of the outer membrane of bacteria. It also prevents the formation of biofilms by bacteria. MATERIALS AND METHODS: In the current study, 120 isolates of Acinetobacter baumannii (A. baumannii) were confirmed by phenotypic and genotypic methods. Antibiogram was performed and then the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of isolates against 5% sodium hypochlorite, ethanol %70, sayasept-HP 2%, chlorhexidine 2%, dettol 4/8% were evaluated. In addition, the disinfectant effect was re-evaluated with the mixture of EDTA solution. All isolates were examined for biofilm presence by crystal violet staining method in triplicates and repeated three times for each strain. Also for all isolates detection of efflux pump genes (Qac-E, qacE-Δ1, SUG-E) by PCR technique was done. RESULTS: Antibiogram results of A. baumannii showed that 6.7% were Multi-drug-resistant (MDR), and 89.2% were Extensively drug-resistant (XDR) isolates. The highest effect of disinfectants was related to 5% sodium hypochlorite, and the least effect was 70% ethanol. EDTA increases the efficacy of selected disinfectants significantly. The highest prevalence of the efflux pump genes was related to SUG-E (95%) and Qac-E (91.7%), and, the qacE-Δ1 gene with 12.5%. The biofilm production rate was 91.3% among all isolates. CONCLUSION: The best and safest way to disinfect hospital floors and surfaces is to choose the right disinfectants, and learn how to use them properly. In this study, a mixture of disinfectants and EDTA had a significant effect on bactericidal activity. it was found that improper use of disinfectants, especially the use of sub-inhibitory dilutions, increases the resistance of bacteria to disinfectants.

Full-length target sequences of GeoMx digital spatial profiling probes reveal that gene-promiscuity predicts probe sensitivity to EDTA tissue decalcification.

GeoMx Digital Spatial Profiling (Nanostring) is a commercial spatial transcriptomics method to selectively analyze regions of interest within intact tissue sections. We show that decalcification with ethylene-diamine-tetra-acetic (EDTA) variably attenuates probe counts, while probes that are more resistant to this effect consequently appear overexpressed after quantile normalization. By determining the undisclosed full-length target sequences of probes used in the human whole transcriptome panel, hereby updating target transcripts and genes, we find that the gene-promiscuity of probes is an important factor that determines sensitivity to EDTA incubation.

Adjunctive intravesical EDTA-tromethamine treatment of a biofilm-associated recurrent Escherichia coli cystitis in a dog.

A 15-month-old spayed female greater Swiss mountain dog was brought to our clinic because of relapsing episodes of urinary tract infection, present since her adoption at 2 mo of age. A diagnosis of chronic bacterial cystitis associated with an invasive, biofilm-forming uropathogenic Escherichia coli was made with bladder-wall histology and fluorescent in situ hybridization analysis. Local treatment with EDTA-tromethamine (EDTA-Tris) infusions along with parenteral cefquinome and prophylactic measures (Type-A proanthocyanidins and probiotics) coincided with clinical and bacterial remission. The dog has been free of clinical signs of urinary tract infection for >4 y. Biofilm-forming uropathogenic E. coli can cause chronic, recurrent cystitis due to low antibiotic efficacy and should be considered in cases of recurrent cystitis in dogs, especially in the absence of identified predisposing factors. This case report describes the diagnostic and therapeutic options that were used to manage a case of this type. Key clinical message: Fluorescent in situ hybridization analysis may be considered in the diagnosis of chronic bacterial cystitis in dogs, and intravesical instillations of EDTA-Tris may be helpful in managing such cases.

Traitement adjuvant intravésical avec de l'EDTA-trométhamine chez un chien présentant une cystite récurrente à Escherichia coli formant des biofilmsUne chienne grand bouvier suisse stérilisée de 15 mois nous a été présentée pour des épisodes d'infection du tractus urinaire récidivants depuis son adoption à l'âge de 2 mois. Une cystite bactérienne chronique associée à un Escherichia coli uropathogène formant des biofilms a été identifiée par l'examen histologique de la paroi vésicale et par hybridation in situ fluorescente. Des instillations intravésicales d'EDTA et trométhamine (EDTA-Tris) en complément d'une antibiothérapie parentérale de courte durée (cefquinome) et de mesures prophylactiques (proanthocyanidines de type A et probiotiques) ont permis une guérison clinique et bactériologique de la cystite pendant plus de 4 ans. Les infections par Escherichia coli formant des biofilms peuvent causer des cystites chroniques récurrentes dues à une faible efficacité des antibiotiques et doivent être incluses dans le diagnostic différentiel des cystites récurrentes chez le chien, particulièrement en l'absence d'autre facteur prédisposant. Ce rapport propose des stratégies diagnostiques et thérapeutiques ayant permis la prise en charge d'un de ces cas.Message clinique clé :L'analyse par hybridation in situ fluorescente peut être envisagé dans le diagnostic de cystite bactérienne chronique chez les chiens, et l'instillation intravésicale d'EDTA-Tris peut être utile dans la gestion de tels cas.(Traduit par les auteurs).

Evaluation of Gallium-68 prostate-specific membrane antigen, positron emission tomography/computed tomography (GA-68 PSMA PET/CT) in recurrent prostate cancer: a retrospective review of initial clinical experience at Tygerberg Hospital.

Introduction: prostate cancer recurrence after definitive therapy for organ-confined disease often manifests as rising prostate-specific antigen (PSA) levels without clinically overt disease. 68Gallium prostate-specific membrane antigen, positron emission tomography/computed tomography (68GaPSMA PET/CT) imaging plays a major role in the management of recurrent prostate cancer. The purpose of this study was to assess the positivity rate of 68Ga PSMA PET/CT scans in cases of prostate cancer recurrence, and to compare the results with existing international literature. Methods: a retrospective analysis of 177 68Ga PSMA PET/CT scans of patients with biochemically proven disease recurrence was performed. The possible association of a positive PSMA PET/CT with the PSA level and Gleason score were analyzed. Results: a total of 177 68Ga PSMA PET/CT scans were performed in 163 patients (median age 66 years). Of these, 117 (66%) scans detected the site of disease recurrence. Among patients with PSA 0.2-0.99 ng/ml, 23/49 (47%, p<0.0001) were positive, and 20/35 (57%, p<0.0005) were positive in the group of patients with PSA 1.00-1.99. When PSA values were further categorized into PSA <2 ng/ml and PSA ≥2 ng/ml, detection rates were 49% and 86% respectively (p <0.0001). The scans were positive in 65% of patients with Gleason score of <7, 62% with Gleason score of =7 and 68% with Gleason score >7 (p=0.745). Conclusion: there was an increase in the detection rate with an increase in the PSA. Gleason score was not a predictor of a positive 68Ga PSMA PET/CT scan. 68Ga-PSMA PET/CT should be prioritized in patients with biochemical recurrence with PSA levels >0.2 ng/ml.

Molecular imaging with 68Ga-PSMA PET/CT in high grade glioma: A biomarker for tumour neo-angiogenesis.

There are several promising radiotracers used for both staging and restaging of primary and recurrent brain tumours based on various mechanisms of tracer localization in tumour cells. 68Ga-PSMA PET has extremely low background uptake in normal brain tissue and consequently high tumour-to-brain ratio making it a promising imaging radiotracer for gliomas. 68Ga-PSMA demonstrates utility in evaluating high grade glioma during both initial workup or when suspecting recurrence. Herein the authors evaluate the role of this imaging modality and the potential future it holds in the management of high grade gliomas.

The effects of EDTA and Trichoderma species on growth and Cu uptake of maize (Zea mays) plants grown in a Cu-contaminated soil.

Metal contamination in soil poses a significant environmental concern worldwide, necessitating effective remediation strategies such as phytoremediation. The present study investigated the effects of EDTA dosage (1.5 and 3 mmol kg-1) and two Trichoderma species (T. harzianum and T. aureoviride) on copper (Cu) content and growth of maize plants grown in a Cu-contaminated soil, as well as Cu fractionation in the soil. In the absence of EDTA, only inoculation with T. harzianum led to a significant increase in shoot biomass. Combining fungal inoculum with EDTA only yielded a significant increase in shoot biomass when using T. aureoviride at a low EDTA rate, highlighting the interplay between fungal species and EDTA rates on plant growth. Results also indicated that EDTA application increased Cu bioavailability, enhancing Cu dissolution and root (not shoot) Cu concentrations. Conversely, inoculation with both Trichoderma species reduced Cu mobility and bioavailability in soil, thereby decreasing the shoot Cu concentrations of plants. When combined with EDTA, only application of T. harzianum resulted in an enhanced shoot Cu concentration, whereas combined application of T. aureoviride and EDTA did not make a significant change compared to the corresponding control (no fungal inoculation, no EDTA), possibly due to a lower compatibility of the T. aureoviride isolate with EDTA. Our results demonstrated that EDTA application, in both non-inoculated and inoculated treatments, increased Cu availability by facilitating its redistribution and transformation from less plant-available fractions (residual, Fe/Mn oxide-bound, and carbonate-bound) to the more readily plant-available forms (water-soluble and exchangeable fractions). In conclusion, although individual Trichoderma application proved beneficial for phytostabilization by reducing Cu content and mitigating Cu toxicity in plants, the combined application of EDTA and a compatible Trichoderma isolate (here, the T. harzianum isolate) holds promise for enhancing the phytoextraction capacity of plants. Although using maize has the advantage of being a food crop, to optimize phytoextraction, plant species with superior metal tolerance and phytoextraction capabilities should be selected, exceeding those of maize.

Stability of adrenocorticotropic hormone in whole blood samples: effects of storage conditions.

Introduction: Adrenocorticotropic hormone (ACTH) is a peptide secreted by pituitary gland that plays an important role in regulating cortisol secretion. Its determination is difficult because of instability in whole blood. Several factors that influence ACTH stability in blood before analysis have been identified: temperature, hemolysis, time to centrifugation and presence of protease inhibitors. Published results on ACTH whole blood stability seem contradictory. Materials and methods: We performed a stability study in 10 healthy volunteers. Three different conditions were tested: ethylenediaminetetraacetic acid (EDTA) at 4 °C, EDTA + aprotinin at 4 °C, EDTA + aprotinin at room temperature. Stability was evaluated for 8 hours. Adrenocorticotropic hormone measurements and hemolysis index were performed respectively on Cobas e602 and c701 (Roche Diagnostics, Mannheim, Germany). We compared percentage deviations with total change limit using a threshold of 7.5%. Results: We showed that ACTH is stable 8 hours with EDTA at 4 °C, 4 hours with EDTA + aprotinin at 4 °C and 2 hours with EDTA + aprotinin at 22 °C. Conclusions: Aprotinin does not appear to give ACTH greater stability but can be used without exceeding 4 hours at 4 °C. Refrigerated pouch transport also seems to be more appropriate for ACTH in whole blood.

Validation of a method for the determination of Aderamastat (FP-025) in K2EDTA human plasma by LC-MS/MS.

Aderamastat (FP-025) is a small molecule, selective matrix metalloproteinase (MMP)-12 inhibitor, under development for respiratory conditions which may include chronic inflammatory airway diseases and pulmonary fibrosis. To support evaluation of the pharmacokinetic parameters of Aderamastat in humans, we developed and validated a high-performance liquid chromatography tandem mass spectrometry (LC-MS/MS) analytical method for the quantification of Aderamastat in human plasma. This assay was validated in compliance with the Food and Drug Administration (FDA) Good Laboratory Practice Regulations (GLP) and European Medicines Agency (EMA) guidelines. K2EDTA human plasma samples were spiked with internal standard, processed by liquid-liquid extraction, and analyzed using reversed-phase HPLC with Turbo Ion Spray® MS/MS detection. Separation was done using a chromatographic gradient on 5 µm C6-Phenyl 110 Å, 50*2 mm analytical column at a temperature of 35 °C. The LC-MS/MS bioanalytical method, developed by QPS Taiwan to determine the concentration of Aderamastat in K2EDTA human plasma, was successfully validated with respect to linearity, sensitivity, accuracy, precision, dilution, selectivity, hemolyzed plasma, lipemic plasma, batch size, recovery, matrix effect, and carry-over. These data indicate that the method for determination of Aderamastat concentrations in human K2EDTA plasma can be used in pharmacokinetics studies and subsequent clinical trials with Aderamastat. Authors declare that, this novel data is not published and not under consideration for publication by another journal than this journal. All data will be made available on request.

A sustainable bioremediation of vanadium from marine environment and value-addition using potential thraustochytrids.

Rising concerns about global environmental degradation underscore the pressing need for effective solutions to combat heavy metal pollution. Industries such as semiconductor and steel production discharge vanadium into marine ecosystems, posing significant risks to both marine life and human health. The current study investigates efficacy of utilizing marine thraustochytrid for efficient vanadium removal outcompeting other microbial sources. By optimizing pH and temperature conditions during harvesting, achieved a remarkable 50.80 % enhancement in vanadium removal efficiency, from 19.31 to 29.12 mg/L. Furthermore, chelating agents EDTA and citric acid supplementation demonstrated promising enhancements, reaching up to 31.21 and 32.59 mg/L, respectively. Notably, vanadium-treated biomass supplemented with citric acid exhibited maximum enhancement in lipid content, from 58.47 to 75.34 %, indicating thraustochytrid's potential for biofuel production. This study presents a sustainable approach for industrial-scale vanadium bioremediation, aligning with Sustainable Development Goals focused on dual benefits of environmental protection and renewable energy.

The effect of ascorbic acid, QMix and other conditioning solutions on the bond strength of adhesively luted glass fiber-reinforced composite posts to root dentin, a laboratory study.

PURPOSE: This study was designed to investigate the effect of post space conditioning with different solutions on the bond strength of glass FRC posts and evaluate the mode of resin failure. METHODS: Sixty extracted human single rooted teeth were root filled using a resin sealer and suitable gutta-percha cones. Post spaces were prepared, and the teeth randomly allocated into 5 groups according to their irrigation regimens which included the following solutions: 17 % EDTA, 2 % CHX, 3 % NaOCl, 10 % ascorbic acid and QMix solutions. Post spaces were irrigated with 5 ml of the solution for 15 s and subsequently washed with distilled water and dried with paper points. Glass FRC posts were cemented into their spaces using a self-adhesive resin cement. The specimens were mounted in plexiglass molds using autopolymerizing acrylic resin. A universal testing machine was used to measure post retention at a crosshead speed of 2 mm/min. The results were analyzed by one-way ANOVA followed by Tukey HSD test (α = 0.05). Dislodged posts and post spaces were examined microscopically to evaluate retention failure. RESULTS: The Ascorbic acid group exhibited the highest mean retentive strength value at 229 N, followed by QMix at 198 N, NaOCl at 186 N, CHX at 170 N, and EDTA at 124 N. The mean value of the ascorbic acid group was significantly higher than EDTA group, p = 0.012. The failure category was primarily mixed. CONCLUSIONS: Rinsing post spaces with ascorbic acid exhibited significantly superior bond strength. The failure mode was mixed. CLINICAL SIGNIFICANCE: Irrigating post spaces with ascorbic acid solution before luting FRC posts significantly improves their bond strength compared to irrigation with EDTA solution. Irrigation with QMix solution produced the second highest retentive strength but showed no statistical significance when compared to using ascorbic acid, NaOCl, CHX, or EDTA solutions.

Performance evaluation of the quantitative assay Adenovirus ELITe MGB® Kit on EDTA-plasma, using the ELITe BeGenius® system.

BACKGROUND: Adenovirus infections constitute an important cause of morbidity and mortality after hematopoietic stem cell transplantation. Detection and monitoring of adenovirus in EDTA-plasma by real-time quantitative PCR is a sensitive tool for identification and management of patients at risk of a potentially fatal infection. OBJECTIVES: The aim of this study was to evaluate the analytical and clinical performance of the quantitative Adenovirus ELITe MGB® Kit (ELITechGroup S.p.A.) using the ELITe BeGenius® (ELITechGroup S.p.A.) system and compare the assay to a laboratory-developed quantitative real-time PCR assay. STUDY DESIGN: Analytical sensitivity of the Adenovirus ELITe MGB® Kit was determined by testing serial dilutions of the WHO standard. Detection of adenovirus serotypes was assessed using a panel of 51 serotypes. Clinical sensitivity and specificity were determined by comparing the Adenovirus ELITe MGB® Kit results with the laboratory-developed assay results of 155 retrospective and prospective EDTA-plasma samples from transplant recipients. RESULTS: The analytical sensitivity of the Adenovirus ELITe MGB® Kit was at least 54 (1.7 Log) IU/mL and the quantitative results showed a high correlation with the WHO standard (R2 = 0.9978; Pearson) within the range of 1.7 to 6.6 Log IU/mL. All 51 adenovirus serotypes were detected. The clinical specificity and sensitivity for EDTA plasma of the Adenovirus ELITe MGB® Kit were 97.4 % and 99.1 % respectively. CONCLUSION: The Adenovirus ELITe MGB® Kit performed on the ELITe BeGenius® system is a highly sensitive and specific assay for the detection of adenovirus in EDTA-plasma from transplantation patients.

Utility of 64Cu-Sarcophagine-Bombesin PET/CT in Men with Biochemically Recurrent Prostate Cancer and Negative or Equivocal Findings on 68Ga-PSMA-11 PET/CT.

Despite a high detection rate of 68Ga-prostate-specific membrane antigen (PSMA) PET/CT in biochemical recurrence (BCR) of prostate cancer, a significant proportion of men have negative 68Ga-PSMA-11 PET/CT results. Gastrin-releasing peptide receptor, targeted by the copper-chelated bombesin analog 64Cu-sarcophagine-bombesin (SAR-BBN) PET/CT, is also overexpressed in prostate cancer. In this prospective imaging study, we investigate the detection rate of 64Cu-SAR-BBN PET/CT in patients with BCR and negative or equivocal 68Ga-PSMA-11 PET/CT results. Methods: Men with confirmed adenocarcinoma of the prostate, prior definitive therapy, and BCR (defined as a prostate-specific antigen [PSA] level > 0.2 ng/mL) with negative or equivocal 68Ga-PSMA-11 PET/CT results within 3 mo were eligible for enrollment. 64Cu-SAR-BBN PET/CT scans were acquired at 1 and 3 h after administration of 200 MBq of 64Cu-SAR-BBN, with further delayed imaging undertaken optionally at 24 h. PSA (ng/mL) was determined at baseline. All PET (PSMA and bombesin) scans were assessed visually. Images were read with masking of the clinical results by 2 experienced nuclear medicine specialists, with a third reader in cases of discordance. Accuracy was defined using a standard of truth that included biopsy confirmation, confirmatory imaging, or response to targeted treatment. Results: Twenty-five patients were enrolled. Prior definitive therapy was radical prostatectomy (n = 24, 96%) or radiotherapy (n = 1, 4%). The median time since definitive therapy was 7 y (interquartile range [IQR], 4-11 y), and the Gleason score was 7 or less (n = 15, 60%), 8 (n = 3, 12%), or 9 (n = 7, 28%). The median PSA was 0.69 ng/mL (IQR, 0.28-2.45 ng/mL). Baseline PSMA PET scans were negative in 19 patients (76%) and equivocal in 6 (24%). 64Cu-SAR-BBN PET-avid disease was identified in 44% (11/25): 12% (3/25) with local recurrence, 20% (5/25) with pelvic node metastases, and 12% (3/25) with distant metastases. The κ-score between readers was 0.49 (95% CI, 0.16-0.82). Patients were followed up for a median of 10 mo (IQR, 9-12 mo). Bombesin PET/CT results were true-positive in 5 of 25 patients (20%), false-positive in 2 of 25 (8%), false-negative in 7 of 25 (28%), and unverified in 11 of 25 (44%). Conclusion: 64Cu-SAR-BBN PET/CT demonstrated sites of disease recurrence in 44% of BCR cases with negative or equivocal 68Ga-PSMA-11 PET/CT results. Further evaluation to confirm diagnostic benefit is warranted.

[68Ga]Ga-PSMA-11 PET and Prostate Cancer Bone Metastases: Diagnostic Performance of Available Standardized Criteria.

In up to two thirds of prostate-specific membrane antigen (PSMA) PET scans, unspecific bone uptake has been described. The aim of this study was to estimate the diagnostic accuracy of [68Ga]Ga-PSMA-11 PET/CT for bone metastases and the occurrence of equivocal lesions. Methods: We analyzed retrospectively 118 patients who underwent a [68Ga]Ga-PSMA-11 PET/CT for initial staging or recurrence evaluation. Lesions were interpreted according to the PSMA reporting and data system (PSMA-RADS) and the prostate cancer molecular imaging standardized evaluation (PROMISE) criteria. The SUVmax and the localization of each lesion were recorded. A combination of prior or follow-up examinations was used as a reference standard to categorize benign and malignant lesions. Correlation between the final diagnosis and imaging or clinicobiochemical parameters was tested. The diagnostic accuracy was calculated for different cutoffs of PSMA-RADS criteria, for PROMISE criteria, and the sequential combination of both. Results: In total, 265 bone abnormalities were identified in 70 of 118 patients. Among these, 148 (55.8%) lesions in 50 (42.4%) patients were classified as PSMA-RADS-3B. There were no PSMA-RADS-3D lesions in our cohort. Equivocal lesions were more frequent on the ribs (30.6%) followed by the pelvis (26.5%), but in the ribs, such an uptake was malignant in 33.3% of cases versus 66.7% in the pelvis. A significant association was found between the final diagnosis and the SUVmax, prostate-specific antigen (PSA), PSA doubling time, International Society of Urological Pathology score, and the number of foci. The sensitivity and specificity were 100% and 63.6% for the PSMA-RADS-3B cutoff, respectively; 40.5% and 100% for the PSMA-RADS-4 cutoff, respectively; and 89.3% and 96.6% for both the PROMISE criteria and the sequential PSMA-RADS/PROMISE strategy, respectively. In the sequential method, the number of equivocal lesions was reduced from 147 to 2. We found that 53% of PSMA-RADS-3B lesions were malignant; 95.5% of lesions classified positive by the sequential method were true positives, whereas 32.6% were false negatives. Conclusion: [68Ga]Ga-PSMA-11 PET/CT has high accuracy for the diagnosis of bone metastases. Equivocal lesions constitute nearly half of the lesions seen on PSMA PET. The sequential combination of PSMA-RADS and PROMISE criteria reduces the number of lesions classified as equivocal. PSMA-RADS-3B lesions which are positive according to the PROMISE criteria should be considered highly suggestive of malignancy.

Quantitative 68Ga-PSMA-11 PET and Clinical Outcomes in Metastatic Castration-resistant Prostate Cancer Following 177Lu-PSMA-617 (VISION Trial).

Background Lutetium 177 [177Lu]Lu-PSMA-617 (177Lu-PSMA-617) is a prostate-specific membrane antigen (PSMA)-targeted radioligand therapy for metastatic castration-resistant prostate cancer (mCRPC). Quantitative PSMA PET/CT analysis could provide information on 177Lu-PSMA-617 treatment benefits. Purpose To explore the association between quantitative baseline gallium 68 [68Ga]Ga-PSMA-11 (68Ga-PSMA-11) PET/CT parameters and treatment response and outcomes in the VISION trial. Materials and Methods This was an exploratory secondary analysis of the VISION trial. Eligible participants were randomized (June 2018 to October 2019) in a 2:1 ratio to 177Lu-PSMA-617 therapy (7.4 GBq every 6 weeks for up to six cycles) plus standard of care (SOC) or to SOC only. Baseline 68Ga-PSMA-11 PET parameters, including the mean and maximum standardized uptake value (SUVmean and SUVmax), PSMA-positive tumor volume, and tumor load, were extracted from five anatomic regions and the whole body. Associations of quantitative PET parameters with radiographic progression-free survival (rPFS), overall survival (OS), objective response rate, and prostate-specific antigen response were investigated using univariable and multivariable analyses (with treatment as the only other covariate). Outcomes were assessed in subgroups based on SUVmean quartiles. Results Quantitative PET parameters were well balanced between study arms for the 826 participants included. The median whole-body tumor SUVmean was 7.6 (IQR, 5.8-9.9). Whole-body tumor SUVmean was the best predictor of 177Lu-PSMA-617 efficacy, with a hazard ratio (HR) range of 0.86-1.43 for all outcomes (all P < .001). A 1-unit whole-body tumor SUVmean increase was associated with a 12% and 10% decrease in risk of an rPFS event and death, respectively. 177Lu-PSMA-617 plus SOC prolonged rPFS and OS in all SUVmean quartiles versus SOC only, with no identifiable optimum among participants receiving 177Lu-PSMA-617. Higher baseline PSMA-positive tumor volume and tumor load were associated with worse rPFS (HR range, 1.44-1.53 [P < .05] and 1.02-1.03 [P < .001], respectively) and OS (HR range, 1.36-2.12 [P < .006] and 1.04 [P < .001], respectively). Conclusion Baseline 68Ga-PSMA-11 PET/CT whole-body tumor SUVmean was the best predictor of 177Lu-PSMA-617 efficacy in participants in the VISION trial. Improvements in rPFS and OS with 177Lu-PSMA-617 plus SOC were greater among participants with higher whole-body tumor SUVmean, with evidence for benefit at all SUVmean levels. ClinicalTrials.gov identifier: NCT03511664 Published under a CC BY 4.0 license. Supplemental material is available for this article.

Assessing the Heterogeneity of Response of [68Ga] Ga-PSMA-11 PET/CT Lesions in Patients With Biochemical Recurrence of Prostate Cancer.

INTRODUCTION: Treatment of men with metastatic prostate cancer can be difficult due to the heterogeneity of response of lesions. [68Ga]Ga-PSMA-11 (PSMA) PET/CT assists with monitoring and directing clinical intervention; however, the impact of response heterogeneity has yet to be related to outcome measures. The aim of this study was to assess the impact of quantitative imaging information on the value of PSMA PET/CT to assess patient outcomes in response evaluation. PATIENTS AND METHODS: Baseline and follow-up (6 months) PSMA PET/CT of 162 men with oligometastatic PC treated with standard clinical care were acquired between 2015 and 2016 for analysis. An augmentative software medical device was used to track lesions between scans and quantify lesion change to categorize them as either new, increasing, stable, decreasing, or disappeared. Quantitative imaging features describing the size, intensity, extent, change, and heterogeneity of change (based on percent change in SUVtotal) among lesions were extracted and evaluated for association with overall survival (OS) using Cox regression models. Model performance was evaluated using the c-index. RESULTS: Forty-one (25%) of subjects demonstrated heterogeneous response at follow-up, defined as having at least 1 new or increasing lesion and at least 1 decreasing or disappeared lesion. Subjects with heterogeneous response demonstrated significantly shorter OS than subjects without (median OS = 76.6 months vs. median OS not reached, P < .05, c-index = 0.61). In univariate analyses, SUVtotal at follow-up was most strongly associated with OS (HR = 1.29 [1.19, 1.40], P < .001, c-index = 0.73). Multivariable models applied using heterogeneity of change features demonstrated higher performance (c-index = 0.79) than models without (c-index = 0.71-0.76, P < .05). CONCLUSION: Augmentative software tools enhance the evaluation change on serial PSMA PET scans and can facilitate lesional evaluation between timepoints. This study demonstrates that a heterogeneous response at a lesional level may impact adversely on patient outcomes and supports further investigation to evaluate the role of imaging to guide individualized patient management to improve clinical outcomes.

Direct addition of EDTA to LABScreen single antigen bead suspension: A simple way to prevent complement mediated interference and streamline HLA antibody testing.

Compromised detection of HLA specific antibodies due to complement mediated interference (CMI) is a well-recognized limitation of the single antigen bead (SAB) assay. Serum treatment with EDTA prior to SAB assay testing is a common strategy used to prevent CMI, however, treatment of individual sera, especially in large clinical runs, can extend assay turnaround time and increase the risk of a sample mix-up. In this study, we describe a simplified EDTA treatment strategy that can be applied simultaneously to all sera in a testing run. This strategy effectively prevents CMI without added pipetting steps and the increased turnaround time associated with other strategies. In the novel bead treatment (BT) method, EDTA solution and SAB suspension are combined and added into the wells of a testing tray together, patient sera are then added to the SAB/EDTA mixture. This eliminates the separate EDTA pre-treatment step used in the standard procedure (ST). Parallel testing using the BT, ST, and no EDTA treatment strategies followed by antibody identification using the Rapid Optimized SAB (ROB) protocol was performed for 19 well characterized sera with known CMI at two different laboratories. Both BT and ST methods were equally effective in preventing CMI. In addition, excellent MFI correlation was observed for specificities not affected by CMI. Both negative and pooled positive control sera performed as expected using the BT method and the pooled positive control serum, specifically designed to exhibit CMI, served well as an EDTA treatment control for all sera. The modified BT protocol can be easily implemented for clinical testing and eliminates extra pipetting steps, reduces the likelihood of pipetting error, and decreases turnaround time, while effectively preventing CMI and ensuring accurate detection of HLA antibodies. This protocol was recently implemented in the Halifax HLA Laboratory and has been very positively received by the laboratory team.

Early Impact of Bevacizumab on the 99m Tc-HYNIC-PSMA-11 Uptake in a Case of Recurrent Glioblastoma Multiforme.

ABSTRACT: Glioblastoma multiforme (GBM) is a highly vascularized tumor with reported high prostate-specific membrane antigen (PSMA) expression. On the other hand, bevacizumab as an antiangiogenesis drug is increasingly used in the treatment of GBM recurrence. We present a case of GBM recurrence with significant reduction of 99m Tc-HYNIC-PSMA-11 uptake in her tumor 1 week after administration of 2 doses of bevacizumab with 2 weeks' interval. This case emphasizes the main mechanism of PSMA uptake in GBM secondary to angiogenesis and also implies a potential interaction of bevacizumab with PSMA uptake that should be especially considered during diagnostic and therapeutic application of PSMA radiotracers in GBM.

Influence of Anticoagulants on the Dissociation of Cardiac Troponin Complex in Blood Samples.

Immunodetection of cardiac isoforms of troponin I (cTnI) and troponin T (cTnT) in blood samples is widely used for the diagnosis of acute myocardial infarction. The cardiac troponin complex (ITC-complex), comprising cTnI, cTnT, and troponin C (TnC), makes up a large portion of troponins released into the bloodstream after the necrosis of cardiomyocytes. However, the stability of the ITC-complex has not been fully investigated. This study aimed to investigate the stability of the ITC-complex in blood samples. A native ITC-complex was incubated in buffer solutions, serum, and citrate, heparin, or EDTA plasma at various temperatures. Western blotting and gel filtration were performed, and troponins were detected using specific monoclonal antibodies. The ITC-complex dissociated at 37 °C in buffers with or without anticoagulants, in citrate, heparin, and EDTA plasmas, and in serum, into a binary cTnI-TnC complex (IC-complex) and free cTnT. In plasma containing heparin and EDTA, the IC-complex further dissociated into free TnC and cTnI. No dissociation was found at 4 °C or at room temperature (RT) in all matrices within 24 h except for EDTA plasma. After incubation at 37 °C in EDTA plasma and serum, dissociation was accompanied by proteolytic degradation of both cTnI and cTnT. The presence of anti-troponin autoantibodies in the sample impeded dissociation of the ITC-complex. The ITC-complex dissociates in vitro to form the IC-complex and free cTnT at 37 °C but is mostly stable at 4 °C or RT. Further dissociation of the IC-complex occurs at 37 °C in plasmas containing heparin and EDTA.

The effect of final irrigation with different solutions on smear layer removal and dentin erosion: A scanning electron microscope study.

AIM: This study aimed to compare the effectiveness of initial irrigation with sodium hypochlorite (NaOCl) and final irrigation with QMix, 40% citric acid, and 17% ethylenediaminetetraacetic acid (EDTA) on smear layer removal and dentin erosion. METHODOLOGY: Forty extracted human mandibular premolar teeth were randomly divided into four groups (n = 10) according to the type of final irrigants used: 17% EDTA, QMix, citric acid, and control (normal saline). Canals were mechanically prepared using ProTaper Next instruments to an apical size of X3. Subsequently, the roots were sectioned in a buccolingual direction. Scanning electron microscopy (SEM) was used to assess the presence of the smear layer and the amount of dentin erosion in the coronal, middle, and apical thirds of the root canals. RESULTS: In regards to smear layer removal, there was a significant difference between the control group and the other tested groups. Moreover, it was significantly higher in the coronal and middle thirds than in the apical third. However, there were no significant differences between the groups of EDTA, QMix, and citric acid. Concerning dentin erosion, citric acid produced significantly more dentin erosion than the other tested groups. CONCLUSION: Final irrigation with solutions had a higher ability to remove the smear layer in the coronal and middle thirds compared to the apical third. Of all the solutions tested, 40% citric acid had the most pronounced impact on dentin erosion, followed by 17% EDTA and QMix.

Calcium-dependent HLA-DQ epitope revealed by EDTA mediated inhibition of antibody reactions in the Luminex single antigen bead assay.

Complement mediated interference with the detection of antibodies targeting HLA is a known limitation of the single antigen bead (SAB) Luminex assay. Ethylenediaminetetraacetic acid (EDTA) is currently the serum treatment of choice in most histocompatibility laboratories to block complement activation by chelating calcium. The purpose of this study was to investigate a serum with an antibody reactivity to HLA-DQ6, 7, 8 and 9 molecules, in the Luminex SAB assay, that was inhibited by treatment with EDTA. Serum was from a 55-year-old highly sensitised female renal transplant candidate that contained, among others, antibodies to an epitope containing the 74EL eplet, shared by HLA-DQ6, DQ7, DQ8 and DQ9 molecules. Serum samples were treated with EDTA, dithiothreitol (DTT), or heat prior to testing by SAB assay. EDTA-treated serum was also tested after the addition of calcium chloride (CaCl2). HLA-DQ-specific antibodies were isolated by adsorption/elution method using three informative donor cells and were tested in the absence or presence of EDTA. The antibody reactivity against HLA-DQ6, DQ7, DQ8 and DQ9 in the SAB assay was significantly inhibited by treating serum and eluates with EDTA and was restored by addition of CaCl2. The study represents the first description of a calcium-dependent epitope in HLA molecules. The relevance of this finding is that the treatment of sera with EDTA could lead to false-negative reactions in the SAB assay, which may compromise virtual crossmatching.