Self-Collection Blood Test for PFASs: Comparing Volumetric Microsamplers with a Traditional Serum Approach.

A remote sampling approach was developed at Eurofins for quantifying per- and polyfluoroalkyl substances (PFASs) in whole blood samples collected using volumetric absorptive microsamplers (VAMSs), which allow for self-collection of blood using a finger prick. This study compares PFAS exposure measured by self-collection of blood using VAMSs to the standard venous serum approach. Blood samples were collected from participants (n = 53) in a community with prior PFAS drinking water contamination using a venous blood draw as well as participant self-collection using VAMSs. Whole blood from the venous tubes was also loaded onto VAMSs to compare differences in capillary vs venous whole blood PFAS levels. Samples were quantified for PFASs using liquid chromatography tandem mass spectrometry and online solid-phase extraction. PFAS levels in serum were highly correlated with measurements in capillary VAMSs (r ≥ 0.91 and p < 0.05). Serum PFAS levels were generally twofold higher than whole blood, reflecting expected differences in their composition. Of interest, FOSA was detected in whole blood (both venous and capillary VAMSs) but not in serum. Overall, these findings indicate that VAMSs are useful self-collection tools for assessing elevated human exposure to PFASs.

Pharmacokinetics of Albendazole, Albendazole Sulfoxide, and Albendazole Sulfone Determined from Plasma, Blood, Dried-Blood Spots, and Mitra Samples of Hookworm-Infected Adolescents.

Albendazole is an effective anthelmintic intensively used for decades. However, profound pharmacokinetic (PK) characterization is missing in children, the population mostly affected by helminth infections. Blood microsampling would facilitate PK studies in pediatric populations but has not been applied to quantify albendazole's disposition. Quantification methods were developed and validated using liquid chromatography-tandem mass spectrometry to analyze albendazole and its metabolites albendazole sulfoxide and albendazole sulfone in wet samples (plasma and blood) and blood microsamples (dried-blood spots [DBS]; Mitra). The use of DBS was limited by a matrix effect and poor recovery, but the extraction efficiency was constant throughout the concentration range. Hookworm-infected adolescents were venous and capillary blood sampled posttreatment with 400 mg albendazole and 25 mg/kg oxantel pamoate. Similar half-life (t1/2 = ∼1.5 h), time to reach the maximum concentration (tmax = ∼2 h), and maximum concentration (Cmax = 12.5 to 26.5 ng/ml) of albendazole were observed in the four matrices. The metabolites reached Cmax after ∼4 h with a t1/2 of ca. 7 to 8 h. A statistically significant difference in albendazole sulfone's t1/2 as determined by using DBS and wet samples was detected. Cmax of albendazole sulfoxide (288 to 380 ng/ml) did not differ among the matrices, but higher Cmax of albendazole sulfone were obtained in the two microsampling devices (22 ng/ml) versus the wet matrices (14 ng/ml). In conclusion, time-concentration profiles and PK results of the four matrices were similar, and the direct comparison of the two microsampling devices indicates that Mitra extraction was more robust during validation and can be recommended for future albendazole PK studies.

Living morphology and molecular phylogeny of oligohymenophorean ciliates associated with freshwater turbellarians.

Three freshwater turbellarian species (Dugesia gonocephala, Girardia tigrina, and Polycelis felina), belonging to the order Tricladida, were examined for the presence of ciliates. Living morphology and phylogenetic position of the isolated ciliates were studied using light microscopy and molecular phylogenetic methods. Three ciliate species, all from the highly diverse class Oligohymenophorea, were detected: Haptophrya planariarum from the subclass Astomatia, Urceolaria mitra from the subclass Peritrichia, and Tetrahymena sp. from the subclass Hymenostomatia. Each of these ciliates is specialized for different parts of the turbellarian bodies: H. planariarum lives in the pharynx and rami of the intestine, U. mitra colonizes the body surface, and Tetrahymena sp. attacks open wounds and feeds on the mesenchyme. Astomes and peritrichs isolated from turbellarians are placed deeper in 18S rRNA gene phylogenies than their relatives isolated from annelids and mollusks. On the other hand, Tetrahymena sp. isolated from turbellarians is classified comparatively deeply within the family Tetrahymenidae, suggesting that the phylogeny of tetrahymenids does not correlate with that of their obligate/facultative host groups. Nevertheless, the reconstruction of ancestral traits corroborated the hypothesis that histophagy was already a life history trait of the progenitor of the subclass Hymenostomatia to which Tetrahymena belongs.

MitraClip: How Do We Reconcile the Inconsistent Findings of MITRA-FR and COAPT?

PURPOSE OF REVIEW: Secondary mitral regurgitation (MR) is a common valvular disorder in patients with left ventricular (LV) dysfunction and is associated with worse morbidity and mortality. New data on percutaneous mitral valve (MV) repair suggest that targeting the valve itself may improve outcomes. Our objective is to review two recent trials (MITRA-FR and COAPT) with regard to percutaneous MV repair. We will dive into their methodology and results and propose potential explanations for their divergent outcomes. RECENT FINDINGS: MITRA-FR and COAPT studied the MitraClip plus guideline-directed medical therapy (GDMT) versus GDMT alone in patients with secondary MR. COAPT found an overwhelming benefit in reduction in HF hospitalization and mortality whereas MITRA-FR found no difference between treatment groups. Patient selection, differences in procedural outcomes, and smaller LV dimensions may explain these diametrically opposed results. Secondary MR is a common valvular disorder with complex pathophysiology. There are certain patients who will not benefit from percutaneous MV repair. The results of MITRA-FR and COAPT suggest that percutaneous MV repair may benefit carefully selected individuals with secondary MR on maximum tolerated doses of GDMT.

Procedural trends, outcomes, and readmission rates pre-and post-FDA approval for MitraClip from the National Readmission Database (2013-14).

BACKGROUND: There are sparse clinical data on the procedural trends, outcomes and readmission rates following FDA approval and expansion of Transcatheter mitral valve repair/MitraClip® . Whether a complex new technology can be disseminated safely and quickly is controversial. METHODS: The study cohort was derived from the National Readmission Data (NRD) 2013-14. MitraClip® was identified using appropriate International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) codes. The primary outcome was a composite of in-hospital mortality + procedural complications. Secondary outcome included 30-day readmissions. Hierarchical two level logistic models were used to evaluate study outcomes. RESULTS: Our analysis included 2003 MitraClip® procedures. Overall in-hospital mortality was 3.9%. As expected, there was a significant increase in procedural volume post-FDA approval. Importantly, a corresponding downward trend in mortality and procedural complications was observed. Significant predictors of in-hospital mortality and procedural complications included the use of vasopressors (P <0.001) and hemodynamic support (P < 0.001). Higher hospital volume (≥10 MitraClips/year) was associated with lower in-hospital mortality and complications (P = 0.02). There were 304 (15.1%) 30-day readmissions, with heart failure being the most common cause of readmission. Elective procedures had lower in-hospital mortality (P < 0.001) and lower readmission rates (P = 0.011) compared with nonelective procedures. CONCLUSION: A significant increase in MitraClip® procedural volumes occurred post-FDA approval. Overall morbidity and mortality were low and trended downwards. Hospital procedure volume ≥10 cases were associated with lower mortality and overall complication rates. These data suggest a successful roll out of a very complex novel structural heart procedure.

Surface-to-volume ratio mapping of tumor microstructure using oscillating gradient diffusion weighted imaging.

PURPOSE: To disentangle the free diffusivity (D0 ) and cellular membrane restrictions, by means of their surface-to-volume ratio (S/V), using the frequency-dependence of the diffusion coefficient D(ω), measured in brain tumors in the short diffusion-time regime using oscillating gradients (OGSE). METHODS: In vivo and ex vivo OGSE experiments were performed on mice bearing the GL261 murine glioma model (n = 10) to identify the relevant time/frequency (t/ω) domain where D(ω) linearly decreases with ω(-1/2) . Parametric maps (S/V, D0 ) are compared with conventional DWI metrics. The impact of frequency range and temperature (20°C versus 37°C) on S/V and D0 is investigated ex vivo. RESULTS: The validity of the short diffusion-time regime is demonstrated in vivo and ex vivo. Ex vivo measurements confirm that the purely geometric restrictions embodied in S/V are independent from temperature and frequency range, while the temperature dependence of the free diffusivity D0 is similar to that of pure water. CONCLUSION: Our results suggest that D(ω) in the short diffusion-time regime can be used to uncouple the purely geometric restriction effect, such as S/V, from the intrinsic medium diffusivity properties, and provides a nonempirical and objective way to interpret frequency/time-dependent diffusion changes in tumors in terms of objective biophysical tissue parameters. Magn Reson Med 76:237-247, 2016. © 2015 Wiley Periodicals, Inc.

Development of mitral stenosis after single MitraClip insertion for severe mitral regurgitation.

We report the first case of mitral stenosis following Mitra-Clip insertion in a patient with symptomatic NYHA IV heart failure, secondary to severe mitral regurgitation (MR). A 79-year-old female with a history of prior aortic valve replacement underwent percutaneous mitral valve (MV) repair. A single clip was advanced coaxially down onto the MV under TOE guidance, with the anterior and posterior leaflets clipped together between A2 and P2. TOE confirmed a significant reduction in MR (grade 4 to grade 1). Despite initial symptomatic relief, she represented 3 months later with similar symptoms. Repeat TOE confirmed a well positioned Mitra-Clip with mild residual MR. However, the possibility of significant mitral stenosis was raised due to the presence of significant turbulence through the bi-orifice valve, with a peak gradient of 25 mm Hg. In addition there was evidence of severe functional tricuspid valve (TV) regurgitation with elevated pulmonary artery pressures (PAP 90 mm Hg), confirmed on subsequent right heart catheterization. After repeated heart team discussions and a failure of optimal medical therapy, and despite a logistic EuroScore of 35.5, minimally invasive surgical replacement of the MV and simultaneous TV repair was undertaken via a right thoracotomy. Despite procedural success and initial good postoperative response, the patient died subsequently from a combination of hospital-acquired pneumonia and significant gastrointestinal bleeding (post operative day 35). Mitra-Clip is a promising novel approach to MV repair. The establishment of further clinical and echocardiographic based selection criteria will help identify the correct patients for this treatment.

Mitra shunt (spleen preserving, side to side lieno-renal shunt) for portal hypertension with hypersplenism in early infancy.

Extrahepatic portal vein obstruction (EHPVO) is the commonest cause of portal hypertension presenting with gastrointestinal bleeding and splenomegaly. Medical management of this condition may provide relief, but involves repeated hospital visits and endoscopic procedures. Surgery is an effective curative solution by lowering portal venous pressure with effective shunting of venous blood from splanchnic to systemic circulation. Shunt surgery for such a small baby has not been previously reported and splenectomy has its own problems. Similarly, banding or sclerotherapy in such babies is not without risk. Among the various shunt options, Mitra shunt (spleen preserving, side-to-side lienorenal shunt), developed and standardized in our own country, stands out as the most optimum surgical treatment for EHPVO in early infancy. We report a 4-month-old baby, youngest recipient of Mitra shunt reported in literature with successful outcome.

Clinical Bridging Studies and Modeling Approach for Implementation of a Patient Centric Sampling Technique in Padsevonil Clinical Development.

Volumetric absorptive microsampling (VAMS) techniques have gained popularity these last years as innovative tool for collection of blood pharmacokinetic (PK) samples in clinical trials as they offer many advantages over dried blood spot and conventional venous blood sampling. The use of Mitra®, a blood collection device based on volumetric absorptive microsampling (VAMS) technology, was implemented during clinical development of padsevonil (PSL), an anti-seizure medication (ASM) candidate. The present study describes the approach used to bridge plasma (obtained from conventional venous blood sampling) and blood exposures (obtained with Mitra®) to support the use of Mitra as sole blood PK sampling method in clinical trials. Paired blood (using Mitra®) and plasma samples (using conventional venous blood sampling) were collected in healthy volunteers as well as in patients with epilepsy. PSL concentration in plasma and blood were analyzed using different approaches which included evaluation of blood-to-plasma ratios (B/P) over time, linear regression, Bland-Altman analysis as well as development of a linear-mixed effect model based on clinical pharmacology studies. Results showed that the observed in vivo B/P and the measured bias between the 2 collection methods were consistent with the measured in vitro B/P. Graphical analysis demonstrated a clear time effect on the B/P which was confirmed in the linear mixed effect model with sampling time identified as significant covariate. Finally, the built-in model was validated using independent datasets and was shown to adequately predict plasma concentration based on blood concentration with a mean bias of less than 9% (predicted versus observed plasma concentration).

Using Mitra sampling to support first-in-human pharmacokinetic evaluations for PF-07059013.

Aim: A sensitive and selective method for the determination of PF-07059013 in dried blood collected by Mitra™ tips was developed and qualified from 50 to 50,000 ng/ml. Materials & methods: PF-07059013 is isolated from 10 µl of human dried blood by extraction with methanol and analyzed by HPLC-MS/MS. Results & conclusions: In addition to routine validation elements, impact of hematocrit and Mitra tip's lot-to-lot variation on assay accuracy were evaluated. The qualified method was used in one clinical study with excellent performance. Correlation coefficient between blood concentrations obtained from liquid-incurred blood samples and dried-incurred blood samples is 0.95. Clinical Trial Registration: NCT04323124 (ClinicalTrials.gov).

Mitral Regurgitation Severity Assessment after Transcutaneous Edge-to-Edge Mitral Valve Repair: Recommended Integration versus Volumetric Assessment Guidelines.

Objectives: This article aims to evaluate the accuracy of the color-Doppler-based technique to evaluate residual mitral regurgitation post TEER. Background: The evaluation of residual mitral regurgitation (MR) post-mitral transcutaneous edge-to-edge repair (mitral TEER) is a critical determinant in patients' outcomes. The common methods used today, based on the integration of color flow Doppler parameters, may be misleading because of the multiple jets and high velocities created by the TEER devices. Methods: Patients undergoing TEER at Hadassah hospital were recruited between 2015 and 2019. Post-procedural MR was evaluated using the integrated qualitative approach as recommended by the guidelines. In addition, the MR volume for each patient was calculated by subtracting the forward stroke volume (calculated by multiplying the LVOT area with the velocity time integral of the LVOT systolic flow) from the total stroke volume (calculated by the biplane Simpson method of discs). We compared the two methods for concordance. Results: Overall, 112 cases were enrolled. In 55.4% of cases, the volumetric residual MR was milder than the MR severity assessed by the guidelines' recommended method. In 25.1%, the MR severity was similar in both methods. In 16.2%, the MR severity was worse when calculated using the volumetric method (pValue < 0.001, Kappameasure of agreement = 0.053). The lower residual MR degree using the volumetric approach was mostly observed in patients classified as "moderate" by the integrated approach. Conclusions: MR severity after TEER is often overestimated by the guideline-recommended integrative method when compared with a volumetric method. Alternative methods should be considered to assess the MR severity after mitral TEER.

Microsampling in pediatric studies: pharmacokinetic sampling for baricitinib (Olumiant™) in global pediatric studies.

Background: Managing blood volumes in pediatric studies is challenging and should be minimized where possible. Results: A sensitive liquid chromatography with tandem mass spectrometry (LC-MS/MS) method was validated and implemented across two phase III global pediatric trials. Two 10-µl aliquots of blood were collected at each time point using the Mitra® device. Concordance between plasma and dried blood was established from older pediatric patients. Incurred sample reanalysis was performed in both studies using the second Mitra tip and acceptance was greater than 83%. Conclusion: The use of microsampling to generate pharmacokinetic data in 2-18-year-old pediatric patients was successfully implemented. Positive feedback was received from clinical sites about the microsampling technique assisting with enrollment of pediatric patients.

Paclitaxel and Therapeutic Drug Monitoring with Microsampling in Clinical Practice.

Paclitaxel is an anticancer agent efficacious in various tumors. There is large interindividual variability in drug plasma concentrations resulting in a wide variability in observed toxicity in patients. Studies have shown the time the concentration of paclitaxel exceeds 0.05 µM is a predictive parameter of toxicity, making dose individualization potentially useful in reducing the adverse effects. To determine paclitaxel drug concentration, a venous blood sample collected 24 h following the end of infusion is required, often inconvenient for patients. Alternatively, using a microsampling device for self-sampling would facilitate paclitaxel monitoring regardless of the patient's location. We investigated the feasibility of collecting venous and capillary samples (using a Mitra® device) from cancer patients to determine the paclitaxel concentrations. The relationship between the venous plasma and whole blood and venous and capillary blood (on Mitra®) paclitaxel concentrations, defined by a Passing-Bablok regression, were 0.8433 and 0.8569, respectively. Demonstrating a clinically acceptable relationship between plasma and whole blood paclitaxel concentration would reduce the need to establish new target concentrations in whole blood. However, in this study, comparison of venous and capillary blood using Mitra® for sampling displayed wide confidence intervals suggesting the results from the plasma and whole blood on this device may not be interchangeable.

Volumetric absorptive microsampling coupled with hybridization LC-MS/MS for quantitation of antisense oligonucleotides.

Background: Volumetric absorptive microsampling has emerged as a less invasive alternative to venous sampling for small-molecule pharmacokinetic studies, but its application to novel therapeutics such as antisense oligonucleotides (ASOs) is not well-established. Results: A workflow was developed using Mitra microsampling coupled with hybridization LC-MS/MS for accurate determination of fomivirsen, a 21-mer ASO, in human blood. Quantitative recovery was achieved regardless of blood hematocrit level or microsample age by implementing impact-assisted extraction. A thorough method evaluation confirmed sensitivity, linearity, precision/accuracy, matrix effect, metabolite interference and four months of microsample stability. Conclusion: The combined impact-assisted extraction and hybridization LC-MS/MS workflow demonstrated the successful quantitation of fomivirsen, establishing the validity and applicability of the approach for ASO drug candidates.

Validation of low-volume sampling devices for pharmacokinetic analysis: technical and logistical challenges and solutions.

While low-volume sampling technologies offer numerous advantages over venipuncture, implementation in clinical trials poses technical and logistical challenges. Bioanalytical methods were validated for measuring the concentration of crenezumab and etrolizumab in dried blood samples collected using Mitra and Tasso-M20. The data generated demonstrate that the concentrations of crenezumab and etrolizumab in dried blood collected by either device could be determined using calibrators prepared in serum. Drug concentrations from dried blood were converted to serum concentrations using patient hematocrit levels. Contract Research Organization experience in sample handling and analysis allowed us to compare differences between various low-volume sampling technologies. This study evaluated challenges and presented potential solutions for use of different low-volume sampling technologies for pharmacokinetic analysis.

Same day discharge after structural heart disease interventions in the era of the coronavirus-19 pandemic and beyond.

With recent advancements in imaging modalities and techniques and increased recognition of the long-term impact of several structural heart disease interventions, the number of procedures has significantly increased. With the increase in procedures, also comes an increase in cost. In view of this, efficient and cost-effective methods to facilitate and manage structural heart disease interventions are a necessity. Same-day discharge (SDD) after invasive cardiac procedures improves resource utilization and patient satisfaction. SDD in appropriately selected patients has become the standard of care for some invasive cardiac procedures such as percutaneous coronary interventions. This is not the case for the majority of structural heart procedures. With the coronavirus disease 2019 pandemic, safely reducing the duration of time spent within the hospital to prevent unnecessary exposure to pathogens has become a priority. In light of this, it is prudent to assess the feasibility of SDD in several structural heart procedures. In this review we highlight the feasibility of SDD in a carefully selected population, by reviewing and summarizing studies on SDD among patients undergoing left atrial appendage occlusion, patent foramen ovale/atrial septal defect closure, Mitra-clip, and trans-catheter aortic valve replacement procedures.

Volumetric absorptive microsampling-LC-MS/MS assays for quantitation of giredestrant in dried human whole blood.

Volumetric absorption microsampling devices offer minimally invasive and user-friendly collection of capillary blood in volumes as low as 10 µl. Herein we describe the assay validation for determination of the selective estrogen receptor degrader giredestrant (GDC-9545) in dried human whole blood collected using the Mitra® and Tasso-M20 devices. Both LC-MS/MS assays met validation acceptance criteria for the linear range 1-1000 ng/ml giredestrant. Mitra and Tasso-M20 samples were stable for 84 and 28 days at ambient conditions, respectively, and for 7-9 days at 40 and -70°C. Blood hematocrit, hyperlipidemia and anticoagulant did not impact quantitation of giredestrant. These validated assays are suitable for the determination of giredestrant in dried blood samples collected using Mitra and Tasso-M20 microsampling devices.

Development and validation of an LC-MS/MS method for the quantification of the anthelmintic drug moxidectin in a volumetric absorptive microsample, blood, and plasma: Application to a pharmacokinetic study of adults infected with Strongyloides stercoralis in Laos.

Moxidectin is a promising candidate for addition to the lean repertoire of drugs against neglected tropical diseases (NTD) including strongyloidiasis. Pharmacokinetic (PK) and -dynamic studies are required to support its clinical development. Microsampling approaches enable PK studies in the challenging environments where NTDs are most prevalent, due to simplified collection and processing. We developed a liquid chromatography tandem mass spectrometry method for the sensitive quantification of moxidectin in human blood obtained by capillary sampling with the microsampling device Mitra® compared to blood and plasma obtained by venous sampling. Sample preparation consisted of protein precipitation, evaporation and reconstitution and also included phospholipid filtration for blood and plasma. Moxidectin was detected by multiple reaction monitoring (640.4 â†’ 528.5 m/z) using a Luna C8(2) (30 × 2.0 mm, 3 µm particle size, 100 Å) analytical column with a gradient program of 6 min duration. Validation was performed with respect to accuracy, precision, sensitivity, selectivity, linearity, stability, recovery, and haematocrit influence with a limit of quantification of 0.5 and 2.5 ng/mL, for venous and capillary blood respectively. Moxidectin was stable up to 2 months at storage condition (blood and plasma: -20 °C, microsamples: room temperature), 3 cycles of temperature shift, for at least 4 h on the bench-top and 24 h in the autosampler (4 °C). Deviations of inter- and intra-assay accuracy and precision were smaller than 12.6% and recoveries were in the range of 80.7-111.2%. The method was applied to samples obtained from nine Strongyloides stercoralis-infected adults from northern Laos. A good agreement in the time-concentration profiles of moxidectin and a high consistency in PK parameters was found between the different matrixes and sampling strategies: e.g. identical time to reach maximal concentration of 4.0 h and a similar maximal concentration of 83.9-88.5 ng/mL of moxidectin. The simple and practical capillary procedure using Mitra® microsampling has been demonstrated to be suitable for PK studies of moxidectin and will pave the way for future PK studies.

Assessment of low volume sampling technologies: utility in nonclinical and clinical studies.

Background: Low volume sampling technologies have come a long way; however, their uptake has been slow due to logistical and perceived implementation challenges. Additional studies are needed to overcome these barriers. Materials & methods/results: Here we present two studies where different sampling technologies were evaluated to determine the feasibility of their implementation. First, we evaluated pharmacokinetic profiles for anti-gD in rats using three tail bleed sampling methods, glass capillary tubes, Shimadzu MSW2® and the Neoteryx Mitra® microsampler. Second, we evaluated two low volume-sampling methods to measure drug levels from patients treated with anti-A therapeutic. This evaluation used whole blood finger pricks for Neoteryx Mitra and plasma from capillary blood using TASSO OnDemand technology to compare results to established venipuncture collection method. Conclusion: These studies evaluate the feasibility and considerations for implementation of different low volume sampling technologies.

Ischemic Mitral Regurgitation: A Multifaceted Syndrome with Evolving Therapies.

Dysfunction of the left ventricle (LV) with impaired contractility following chronic ischemia or acute myocardial infarction (AMI) is the main cause of ischemic mitral regurgitation (IMR), leading to moderate and moderate-to-severe mitral regurgitation (MR). The site of AMI exerts a specific influence determining different patterns of adverse LV remodeling. In general, inferior-posterior AMI is more frequently associated with regional structural changes than the anterolateral one, which is associated with global adverse LV remodeling, ultimately leading to different phenotypes of IMR. In this narrative review, starting from the aforementioned categorization, we proceed to describe current knowledge regarding surgical approaches in the management of IMR.