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Background: Research investigating the potential link between gingival microvascular blood flow and inflammatory status is scarce. This study aims to assess color doppler flow imaging (CDFI) and micro-flow imaging (MFI) as tools for the assessment of gingival papilla blood flow (GPBF) and to examine their diagnostic utility as a noninvasive means of detecting gingival bleeding. Methods: CDFI and MFI were used to assess the GPBF grade (0–4) of 140 anterior gingival papilla sites in advanced periodontitis patients. Correlations between GPBF grades and periodontal characteristics were examined, and diagnostic performance as a means of predicting bleeding on probing (BOP) was examined using receiver operating characteristic curves. Results: GPBF grades 0 and 1 assessed by the MFI were 14.29% and 15.71% respectively, lower than the 28.57% and 24.29% assessed by the CDFI. In contrast, MFI detected a higher frequency of GPBF grade 2 sites (40.71%) relative to CDFI (22.14%). The CDFI and MFI provided consistent results in 62.14% of the sites, while the MFI demonstrated higher ratings in rest 37.86% of the sites. A significant positive correlation was detected between GPBF grade and the modified gingival index (MGI), bleeding index (BI), BOP, and probing depth (PD). It showed high accuracy for CDFI or MFI to diagnosing BOP with a sensitivity of 80.51% and 96.43% and a specificity of 77.27% and 57.14%, respectively. Area under the receiver operator characteristic curve values when predicting BOP based on the GPBF grade determined using CDFI and MFI approaches 0.887 (95% CI 0.833–0.942) and 0.917 (95% CI 0.862–0.972), respectively, and there were no significant differences between these values (Z = − 1.502, p = 0.133). Conclusions: Both MFI and CDFI can be employed for the evaluation of GPBF, and MFI is better suited to detecting mild inflammation. Trial registration ChiCTR2200066021 (Date of registration: 22/11/2022). [ABSTRACT FROM AUTHOR]

Purpose This study aimed to determine whether micro-flow imaging (MFI) offers diagnostic performance comparable to that of contrast-enhanced ultrasonography (CEUS) in detecting segmental congestion among patients undergoing living donor liver transplantation (LDLT). Methods Data from 63 patients who underwent LDLT between May and December 2022 were retrospectively analyzed. MFI and CEUS data collected on the first postoperative day were quantified. Segmental congestion was assessed based on imaging findings and laboratory data, including liver enzymes and total bilirubin levels. The reference standard was a postoperative contrast-enhanced computed tomography scan performed within 2 weeks of surgery. Additionally, a subgroup analysis examined patients who underwent reconstruction of the middle hepatic vein territory. Results The sensitivity and specificity of MFI were 73.9% and 67.5%, respectively. In comparison, CEUS demonstrated a sensitivity of 78.3% and a specificity of 75.0%. These findings suggest comparable diagnostic performance, with no significant differences in sensitivity (P=0.655) or specificity (P=0.257) between the two modalities. Additionally, early postoperative laboratory values did not show significant differences between patients with and without congestion. The subgroup analysis also indicated similar diagnostic performance between MFI and CEUS. Conclusion MFI without contrast enhancement yielded results comparable to those of CEUS in detecting segmental congestion after LDLT. Therefore, MFI may be considered a viable alternative to CEUS.

Abstract Background Research investigating the potential link between gingival microvascular blood flow and inflammatory status is scarce. This study aims to assess color doppler flow imaging (CDFI) and micro-flow imaging (MFI) as tools for the assessment of gingival papilla blood flow (GPBF) and to examine their diagnostic utility as a noninvasive means of detecting gingival bleeding. Methods CDFI and MFI were used to assess the GPBF grade (0–4) of 140 anterior gingival papilla sites in advanced periodontitis patients. Correlations between GPBF grades and periodontal characteristics were examined, and diagnostic performance as a means of predicting bleeding on probing (BOP) was examined using receiver operating characteristic curves. Results GPBF grades 0 and 1 assessed by the MFI were 14.29% and 15.71% respectively, lower than the 28.57% and 24.29% assessed by the CDFI. In contrast, MFI detected a higher frequency of GPBF grade 2 sites (40.71%) relative to CDFI (22.14%). The CDFI and MFI provided consistent results in 62.14% of the sites, while the MFI demonstrated higher ratings in rest 37.86% of the sites. A significant positive correlation was detected between GPBF grade and the modified gingival index (MGI), bleeding index (BI), BOP, and probing depth (PD). It showed high accuracy for CDFI or MFI to diagnosing BOP with a sensitivity of 80.51% and 96.43% and a specificity of 77.27% and 57.14%, respectively. Area under the receiver operator characteristic curve values when predicting BOP based on the GPBF grade determined using CDFI and MFI approaches 0.887 (95% CI 0.833–0.942) and 0.917 (95% CI 0.862–0.972), respectively, and there were no significant differences between these values (Z = − 1.502, p = 0.133). Conclusions Both MFI and CDFI can be employed for the evaluation of GPBF, and MFI is better suited to detecting mild inflammation. Trial registration ChiCTR2200066021 (Date of registration: 22/11/2022).

Microvascular ultrasound (MVUS) is a new ultrasound technique that allows the detection of slow-velocity flow, providing the visualization of the blood flow in small vessels without the need of intravenous contrast agent administration. This technology has been integrated in the most recent ultrasound equipment and applied for the assessment of vascularization. Compared to conventional color Doppler and power Doppler imaging, MVUS provides higher capability to detect intralesional flow. A growing number of studies explored the potential applications in hepatobiliary, genitourinary, and vascular pathologies. Different flow patterns can be observed in hepatic and renal focal lesions providing information on tumor vascularity and improving the differential diagnosis. This article aims to provide a detailed review on the current evidences and applications of MVUS in abdominal imaging. [ABSTRACT FROM AUTHOR]

Purpose: During biopharmaceutical drug manufacturing, storage, and distribution, proteins in both liquid and solid dosage forms go through various processes that could lead to protein aggregation. The extent of aggregation in the sub-micron range can be measured by analyzing a liquid or post-reconstituted powder sample using Micro-Flow Imaging (MFI) technique. MFI is widely used in biopharmaceutical industries due to its high sensitivity in detecting and analyzing particle size distribution. However, the MFI's sensitivity to various factors makes accurate measurement challenging. Therefore, in light of the inherent variability of the method, this work aims to explore the capabilities of an adopted coupled sensitivity analysis and machine learning algorithm to quantify the influencing factors on the formed sub-visible particles and method variability. Methods: The proposed algorithm consists of two interconnected components, namely a surrogate model with a neural network and a sensitivity analyzer. A machine learning tool based on artificial neural networks (ANN) is constructed with MFI data. The best fit with an optimized configuration is found. Sensitivity and uncertainty analysis is performed using this network as the surrogate model to understand the impacts of input parameters on MFI data. Results: Results reveal the most impactful reconstitution preparation factors and others that are masked by the instrument variabilities. It is shown that instrument inaccuracy is a function of size category, with higher variabilities associated with larger size ranges. Conclusion: Utilizing this tool while assessing the sensitivity of outputs to various parameters, measurement variabilities for analytical characterization tests can be quantified. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the value of simultaneous display of contrast‐enhanced ultrasound and micro‐flow imaging technology (CEUS‐MFI) in intra‐tumoral vessel detection and hepatic tumor diagnosis. Methods: A total of 82 patients with 82 focal liver lesions were enrolled in this study. Each patient received ultrasound exams including color Doppler flow imaging (CDFI), micro‐flow imaging (MFI), contrast‐enhanced ultrasound (CEUS), and CEUS‐MFI with a Philips EPIQ7 ultrasound imaging system. The intra‐tumoral vessels detected by CDFI, MFI, and CEUS‐MFI were compared, respectively. The accuracy and confidence of using CEUS and CEUS‐MFI in diagnosing hepatic tumors were also compared. Results: CEUS‐MFI was capable of detecting more hepatic intra‐tumoral vessels than MFI (P =.000) and CDFI (P =.000). Compared with CEUS, CEUS‐MFI improved the diagnostic accuracy of hepatic lesions (P =.009). Particularly, among the correctly diagnosed hepatic lesions, the number of cases where radiologists diagnosed with great confidence was increased from 88.4% (61/69) with CEUS only to 92.4% (73/79) with CEUS‐MFI (P =.041). Conclusions: CEUS‐MFI is sensitive in detecting hepatic intra‐tumoral vessels and can improve the accuracy and confidence of radiologists in diagnosing hepatic lesions. [ABSTRACT FROM AUTHOR]

Objective: Monitoring microcirculation and visualizing microvasculature are critical for providing diagnosis to medical professionals and guiding clinical interventions. Ultrasound provides a medium for monitoring and visualization; however, there are challenges due to the complex microscale geometry of the vasculature and difficulties associated with quantifying perfusion. Here, we studied established and state‐of‐the‐art ultrasonic modalities (using six probes) to compare their detection of slow flow in small microvasculature. Methods: Five ultrasonic modalities were studied: grayscale, color Doppler, power Doppler, superb microvascular imaging (SMI), and microflow imaging (MFI), using six linear probes across two ultrasound scanners. Image readability was blindly scored by radiologists and quantified for evaluation. Vasculature visualization was investigated both in vitro (resolution and flow characterization) and in vivo (fingertip microvasculature detection). Results: Superb Microvascular Imaging (SMI) and Micro Flow Imaging (MFI) modalities provided superior images when compared with conventional ultrasound imaging modalities both in vitro and in vivo. The choice of probe played a significant difference in detectability. The slowest flow detected (in the lab) was 0.1885 ml/s and small microvasculature of the fingertip were visualized. Conclusions: Our data demonstrated that SMI and MFI used with vascular probes operating at higher frequencies provided resolutions acceptable for microvasculature visualization, paving the path for future development of ultrasound devices for microcirculation monitoring. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to determine whether micro-flow imaging (MFI) offers diagnostic performance comparable to that of contrast-enhanced ultrasonography (CEUS) in detecting segmental congestion among patients undergoing living donor liver transplantation (LDLT)., Methods: Data from 63 patients who underwent LDLT between May and December 2022 were retrospectively analyzed. MFI and CEUS data collected on the first postoperative day were quantified. Segmental congestion was assessed based on imaging findings and laboratory data, including liver enzymes and total bilirubin levels. The reference standard was a postoperative contrast-enhanced computed tomography scan performed within 2 weeks of surgery. Additionally, a subgroup analysis examined patients who underwent reconstruction of the middle hepatic vein territory., Results: The sensitivity and specificity of MFI were 73.9% and 67.5%, respectively. In comparison, CEUS demonstrated a sensitivity of 78.3% and a specificity of 75.0%. These findings suggest comparable diagnostic performance, with no significant differences in sensitivity (P=0.655) or specificity (P=0.257) between the two modalities. Additionally, early postoperative laboratory values did not show significant differences between patients with and without congestion. The subgroup analysis also indicated similar diagnostic performance between MFI and CEUS., Conclusion: MFI without contrast enhancement yielded results comparable to those of CEUS in detecting segmental congestion after LDLT. Therefore, MFI may be considered a viable alternative to CEUS.

BACKGROUND: Tumor angiogenesis plays a critical role in the growth and metastasis of breast cancer. Evaluating the added value of vascular features to Breast Imaging Reporting and Data System (BI-RADS) in differentiating malignant masses from benign ones is essential. Micro-flow Imaging (MFI) is a promising noninvasive diagnostic method for the microvessels in breast tumors, but its precise value is still uncertain. OBJECTIVES: Understanding whether malignant tumor vascular characteristics by MFI are associated with breast cancer and whether the diagnostic efficiency varies by age. MATERIALS AND METHODS: B-mode ultrasound and MFI were performed for 153 solid breast lesions. The vessels images by MFI were reviewed and assessed by two investigators, respectively. Then the diagnostic efficacy of different vascular features combined with BI-RADS was evaluated in different age groups. RESULTS: The mean size of lesions is 19.4 (range 18–78) mm. There were 94 breast masses in benign, while 59 breast masses in malignant by pathology. III Adler classification, penetrating vessels, and complex flow pattern showed a positive association with a high risk of malignant breast lesions (p < 0.05). BI-RADS combined with vessel characteristics show better improvement of diagnostic performance of breast lesions in the elderly group than in the young group. CONCLUSIONS: Vascular features by MFI contribute to malignant breast masses' diagnosis, and the association might be modified by age. [ABSTRACT FROM AUTHOR]

Previously our laboratory first reported that dropping of freeze-dried monoclonal antibody (mAb) formulations could cause protein degradation and aggregation (J Pharm Sci, 2021, 1625). In this manuscript, we evaluated effects of secondary package on stability of several freeze-dried biopharmaceutical formulations during dropping. The degradation of mAb-Y during dropping with different secondary packages was determined by the sensitive particle analyzing techniques micro-flow imaging (MFI) and dynamic light scattering (DLS). Electron paramagnetic resonance (EPR) was used to detect free radicals after repeated dropping in different secondary packages. The amount of free radicals and SbVPs was correlated to the sample temperature as well as the secondary package during dropping. Our observations suggest that secondary packaging has significant effect on freeze-dried biopharmaceutical stability during dropping and therefore should be thoroughly screened and optimized to assure high product quality even for the presumed highly stable freeze-dried biopharmaceuticals. [ABSTRACT FROM AUTHOR]

Purposes: Liquid protein-based biopharmaceutical formulations have been reported to form aggregation and protein sub-visible particles (SbVPs) during dropping (Randolph et al., J Pharm Sci 2015, 104, 602). However, effects of secondary package on liquid biopharmaceutical formulation stability during dropping are overlooked and have not been reported so far. This study reports the first real-world evaluation on effects of secondary package on liquid biopharmaceutical formulation stability during dropping, using two monoclonal antibodies (mAb-1 and mAb-2) and one fusion protein (FP-1) as model biopharmaceuticals. Methods: The potential protective effects of secondary package and formulation composition on liquid biopharmaceutical formulations during dropping were evaluated with micro-flow imaging (MFI) and dynamic light scattering (DLS). Results: The dropping-induced degradation could be detected with the two sensitive particle analyzing techniques MFI and DLS. Formulation compositions have dramatic impact on biopharmaceutical stability during dropping. Surprisingly, unlike the primary packages that have been reported to impact liquid biopharmaceutical stability, the secondary packaging system as described in our current preliminary design has little or no protective effect during dropping. Conclusions: Our study is the first real-world data showing that the secondary package system has little to no effect on the liquid biopharmaceutical formulation quality during dropping. On the contrary, the stability of liquid biopharmaceutical formulations during dropping is more relevant to formulation compositions and primary packages. [ABSTRACT FROM AUTHOR]

Dropping during shipping and handling of liquid biopharmaceutical formulations has long been known to cause protein degradation and aggregation. On the other hand, accidental dropping of freeze-dried protein formulations is generally considered not a major issue for biopharmaceutical quality. Reports of stability and especially the underling degradation mechanism(s) during shipping and handling of freeze-dried protein formulations were rarely seen in literature. In this manuscript, we report an interesting phenomenon in which repeated dropping of freeze-dried monoclonal antibody X (mAb-X) formulation powder resulted in significant protein sub-visible particles (SbVPs) in the reconstituted liquid as determined by the sensitive particle analyzing technique micro-flow imaging (MFI). Free radicals were observed after repeated dropping by electron paramagnetic resonance (EPR). Formation of SbVPs could be partially inhibited by the free radical scavengers methionine and 3-carbamoyl-2,2,5,5-tetramethyl-1-pyrrolidin-yloxy free radical (CTPO). The amount of free radicals and SbVPs was correlated to the sample temperature during dropping. Therefore we propose that the high temperature formed during dropping was probably the root cause for protein aggregation and free radical formation, which could further cause protein aggregation. Our observations suggest that similar to liquid protein formulations, dropping of freeze-dried protein formulations should also be avoided or mitigated. [ABSTRACT FROM AUTHOR]

We have observed an interesting phenomenon in which grinding of freeze-dried monoclonal antibody X (mAb-X) formulation powder resulted to significant protein sub-visible particles (SbVPs) in the reconstituted liquid, which could only be observed by sensitive particle analytical methods such as MFI and DLS. Effects of grinding temperature and the free radical scavengers methionine and 3-carbamoyl-2,2,5,5-tetramethyl-1-pyrrolidin-yloxy free radical (CTPO) on the formation of SbVPs were also evaluated. Free radicals were observed by EPR and the amount of free radicals was correlated to the sample temperature prior to grinding. Formation of SbVPs could be partially inhibited by methionine and CTPO. The amount of SbVPs formed was dependent on the amount of free radicals/sample temperature prior to grinding. At higher temperatures, more free radicals and SbVPs formed. Other than the previously known protein degradation due to high temperature formed during mechanical grinding, we propose an unreported and supplementary mechanism, i.e., the formation of free radicals (i.e., due to break of C O or C S bonds) in the dried state during mechanical grinding, leading to protein particle formation in the reconstituted solution. Our observation suggested that mechanical grinding of protein powder should be avoided or used cautiously (i.e., grinding temperature, strength and time) and the effects on radical and particle formation be fully evaluated. [ABSTRACT FROM AUTHOR]

The purpose of the study was to evaluate the vascular architecture of focal liver lesions with the newly released non-contrast micro-flow imaging (MFI) technique. Eighty patients with 80 hepatic tumors were enrolled in this study. The richness of displayed blood flow was first compared with color Doppler flow imaging using grades according to Adler's method. The results indicated that MFI outperformed color Doppler flow imaging with a statistically significant difference (p <0.0001). With the enhanced position in arterial phase of contrast-enhanced ultrasound imaging as the ground truth, the displayed blood flow distribution within tumors in MFI was further evaluated. The coincidence rate between MFI and contrast-enhanced ultrasound was 73.75% (59/80), which was higher than that of color Doppler flow imaging (52.5%, 42/80) (p < 0.0001). Moreover, for the five cases of focal nodular hyperplasia, MFI clearly revealed the spoke-wheel or radiating intra-tumoral vasculature, a finding specific to the diagnosis of focal nodular hyperplasia. [ABSTRACT FROM AUTHOR]

Quantification and size distribution characterization of subvisible particles in parenteral biopharmaceutics, present as both proteinaceous and nonproteinaceous particles in the size range from 0.1 to 100 μm, are important for biopharmaceutical industry due to their potential safety and efficacy implications. Although a number of analytical techniques are available to count and size subvisible particles, characterization of particles ≤2 μm remains a significant challenge due to technical limitations of existing particle counting instruments. In this article, we demonstrate the ability of an optimized flow cytometry system to detect and quantify size distribution of subvisible particles without additional labeling that includes the critical submicron range in biopharmaceutical formulations. In addition, these qualitative and quantitative determinations are performed in a high-throughput manner using sample volumes that allow statistically significant evaluations. This approach can be used not only to ascertain the quality of therapeutic protein products but also to evaluate numerous conditions during the screening of drug candidates and their prospective formulations. [ABSTRACT FROM AUTHOR]

The productivity of cell culture-derived vaccines grown in anchorage-dependent animal cells is limited by bioreactor surface area. One way to increase the available surface area is by growing cells as monolayers on small spheres called microcarriers, which are approximately 100-250 μm in diameter. In order for microcarrier-based cell culture to be a success, it is important to understand the kinetics of cell growth on the microcarriers. Micro-flow imaging (MFI) is a simple and powerful technique that captures images and analyzes samples as they are drawn through a precision flow cell. In addition to providing size distribution and defect frequency data to compare microcarrier lots, MFI was used to generate hundreds of images to determine cell coverage and confluency on microcarriers. Same-day manual classification of these images provided upstream cell culture teams with actionable data that informed in-process decision making (e.g. time of infection). Additionally, an automated cell coverage algorithm was developed to increase the speed and throughput of the analyses. [ABSTRACT FROM AUTHOR]

The present study aimed to determine the usefulness of contrast-enhanced ultrasonography (CEUS) with Sonazoid in evaluating the therapeutic response to sorafenib for hepatocellular carcinoma (HCC). In total, 26 patients with advanced HCC who received sorafenib and were followed up by CEUS were enrolled in the present study. CEUS was performed prior to and within 2-4 weeks of treatment, and the images of the target lesion in the post-vascular phase with a re-injection method were analyzed. The presence (+) or absence (-) of intratumoral necrosis and the intratumoral vascular architecture on micro-flow imaging (MFI) were compared prior to and subsequent to treatment. Target lesions that exhibited non-enhancement after re-injection were considered to indicate intratumoral necrosis. The intratumoral vascular architecture was classified into three groups, as follows: Vd, the intratumoral vessels visually narrowed or decreased; Vnc, the vessels remained unchanged; and Vi, the vessels were thickened or increased. Survival curves were estimated using the Kaplan-Meier method and compared using the log rank test between the intratumoral necrosis (+) and (-) groups, and among the Vd, Vnc and Vi groups. P<0.05 was considered to indicate a statistically significant difference. The number of patients in the intratumoral necrosis (+) and (-) groups was 8 and 18 patients, respectively, and the median survival time (MST) was 7.2 months [95% confidence interval (CI), 2.2-12.2] and 9.5 months (95% CI, 5.1-13.8), respectively (P=0.44). The MFI findings were observed in 11 patients in the Vd group, 10 patients in the Vnc group and 5 patients in the Vi group. The MSTs in the Vd, Vnc and Vi groups were 15.6 months (95% CI, 5.0-23.3), 11.0 months (95% CI, 3.5-17.6) and 3.6 months (95% CI: 1.2-6.0), respectively. The P-value for the differences between the Vd and Vnc groups, Vd and Vi groups, and Vnc and Vi groups were 0.78, 0.016 and 0.047, respectively, which indicated that the survival time decreased significantly in the Vi group. Evaluation of intratumoral vascular architecture using MFI demonstrates promise for assessing the therapeutic response to sorafenib in patients with HCC. [ABSTRACT FROM AUTHOR]

Inducing protein aggregation in vitro under various formulation and stress conditions may lead to an increased understanding of the different association routes a protein can undergo. However, a range of factors can affect the aggregation process, often leading to heterogenous samples and experimental irreproducibility between labs. Here, we present detailed methods to reproducibly form homogenous samples of superstructures: amyloid-like fibrils, spherulites, and particulates from human insulin. We discuss pitfalls and good practice in the lab, with the aim of creating awareness on the potential sources of artefacts for protein stability and aggregation studies., (© 2023. Springer Science+Business Media, LLC, part of Springer Nature.)

Abstract: The main purpose of this manuscript is to describe a phenomenon in which vacuum degassing a reconstituted freeze-dried fusion protein etanercept formulation caused a significant amount of protein sub-visible particles (SbVP). Physical stability of etanercept was monitored by micro-flow imaging (MFI), dynamic light scattering (DLS), size-exclusion high pressure liquid chromatography (SE-HPLC) and far- and near-ultraviolet circular dichroism (far- and near-UV CD). One potential explanation of this phenomenon is that bubble collapses when the vacuum is applied, leads to substantial heat formation, and ultimately free radical formation. Subsequently, the effect of a free-radical scavenger (ascorbic acid, AA) on SbVP formation was also evaluated. Degassing of etanercept solution by applying vacuum caused substantial increase of SbVP, as detected by MFI and DLS. However, traditional techniques such as SE-HPLC could not detect any change. The addition of free-radical scavenger had minimal effect on SbVP formation, therefore the formation of free radicals was probably not the main cause for this effect. [Copyright &y& Elsevier]

We tested the hypothesis that foreign particles shed from filters can accelerate the rate of protein aggregation and particle formation during agitation stress. Various types and brands of syringe filters were tested. Particle counts and size distribution (≥1 µm) in buffer alone or in solutions of keratinocyte growth factor 2 (KGF-2) were determined with a micro-flow imaging. Submicron particle populations were characterized by dynamic light scattering. Loss of soluble protein during filtration or postfiltration incubation was determined by ultraviolet spectroscopy and bicinchoninic acid protein assay. There was a wide range (from essentially none to >100,000/mL) in the counts for at least 1 µm particles shed into buffer or KGF-2 solution from the different syringe filters (with or without borosilicate glass microfibers). Filtration of KGF-2 with units containing glass microfibers above the membrane resulted in 20%-80% loss of protein due to adsorption to filter components. Filtration with systems containing a membrane alone resulted in 0%-20% loss of KGF-2. Effects of 24-h postfiltration incubation were tested on KGF-2 solution filtered with polyether sulfone membrane filters. Loss of soluble protein and formation of particles during agitation were much greater than that in control, unfiltered KGF-2 solutions. Similar acceleration of protein aggregation and particle formation was observed when unfiltered KGF-2 solution was mixed with filtered buffer and agitated. Particle shedding from syringe filters-and the resulting acceleration of protein aggregation during agitation-varied greatly among the different syringe filters and individual units of a given filter type. Our results demonstrate that nanoparticles and microparticles shed from the filters can accelerate protein aggregation and particle formation, especially during agitation. © 2012 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 101:2952-2959, 2012 [ABSTRACT FROM AUTHOR]

The need to monitor, measure, and control sub-visible proteinaceous particulates in biopharmaceutical formulations has been emphasized in recent publications and commentaries. Some of these particulates can be highly transparent, fragile, and unstable. In addition, for much of the size range of concern, no practical measurement method with adequate sensitivity and repeatability has been available. A complication in measuring protein particulates in many formulations is the simultaneous presence of other particle types such as silicone micro-droplets, air bubbles, and extrinsic contaminants. The need has therefore been identified for new analytical methods which can accurately measure and characterize sub-visible particulates in formulations. Micro-flow imaging has been shown to provide high sensitivity in detecting and imaging transparent protein particles and a unique capability to independently analyze such populations even when other particle types are present. [ABSTRACT FROM AUTHOR]

Objective: To explore the value of micro-flow imaging (MFI) in evaluating blood flow characteristics and differential diagnosis of gallbladder polypoid lesions., Methods: We retrospectively analyzed the clinical data and ultrasound images of 73 patients with gallbladder polypoid lesions, including 24 patients with pathologically confirmed neoplastic polyps ( n =24) and 49 with non-neoplastic polyps ( n =49). All the patients underwent conventional ultrasound, MFI and contrast enhanced ultrasound (CEUS) before cholecystectomy. The blood flow characteristics of the lesions in color Doppler flow imaging (CDFI) and MFI were compared, and the consistency of the findings by these two modalities with those of CEUS were evaluated by weighted Kappa consistency test. The diagnostic performance of MFI for gallbladder polypoid lesions was assessed., Results: There were significant differences between MFI and CDFI in the evaluation of blood flow characteristics of gallbladder polypoid lesions (χ 2 =37.684, P < 0.001). MFI showed better performance than CDFI in displaying the blood flow characteristics of the polyps. The consistency in the findings was 0.118 between CDFI and CEUS and 0.816 between MFI and CEUS. The sensitivity, specificity and accuracy of MFI in distinguishing neoplastic polyps from non-neoplastic polyps were 75.00%, 93.88% and 87.67%, respectively., Conclusion: MFI has a good consistency with CEUS in displaying the blood flow characteristics of gallbladder polypoid lesions and can accurately distinguish neoplastic polyps from non-neoplastic polyps, thus providing new ultrasound diagnostic evidence to support clinical decisions on optimal treatments of gallbladder polypoid lesions.

Simple Summary: Ultrasound-guided fine needle aspiration cytology (USgFNAC) is commonly used for N-staging in head and neck squamous cell carcinoma (HNSCC). The specificity of USgFNAC is always in the order of 100% as false positive cytology is rare. The difference in sensitivity is mainly attributable to selection of the lymph nodes to aspirate and aspiration technique. The aim of this study was to improve the selection criteria of lymph nodes to aspirate. Ultrasound features of nodes such as a short axis diameter, S/L ratio, loss of a fatty hilum sign, resistive index, and peripheral or mixed hilar and peripheral vascularization, obtained by Micro-flow imaging (MFI), which is a new technique to obtain micro-vascularization, were evaluated. To calculate the sensitivity and PPV of each feature, data of sonographic findings and cytological results of all aspirated nodes were statistically analyzed. We found that next to size, peripheral vascularisation obtained by MFI and absent hilum sign have a high predictive value for malignancy and should be added as selection criteria for fine needle aspiration in lymph nodes. Ultrasound-guided fine needle aspiration cytology (USgFNAC) is commonly used for nodal staging in head and neck squamous cell cancer (HNSCC). Peripheral vascularity is a described feature for node metastasis. Micro-flow imaging (MFI) is a new sensitive technique to evaluate micro-vascularization. Our goal is to assess the additional value of MFI to detect malignancy in lymph nodes. A total of 102 patients with HNSCC were included prospectively. USgFNAC was performed with the Philips eL18–4 transducer. Cytological results served as a reference standard to evaluate the prediction of cytological malignancy depending on ultrasound features such as resistive index (RI), absence of fatty hilum sign, and peripheral vascularization. Results were obtained for all US examinations and for the subgroup of clinically node-negative neck (cN0). USgFNAC was performed in 211 nodes. Peripheral vascularization had a positive predictive value (PPV) of 83% (cN0: 50%) and the absence of a fatty hilum had a PPV of 82% (cN0 50%) The combination of peripheral vascularization and absent fatty hilum had a PPV of 94% (cN0: 72%). RI (threshold: 0.705) had a PPV of 61% (cN0: RI-threshold 0.615, PPV 20%), whereas the PPV of short axis diameter (threshold of 6.5mm) was 59% for all patients and 19% in cN0 necks (threshold of 4 mm). Peripheral vascularization assessed by MFI and absent hilum has a high predictive value for cytological malignancy in neck metastases. Next to size, both features should be used as additional selection criteria for USgFNAC. [ABSTRACT FROM AUTHOR]

Objective To evaluate the performance of micro-flow imaging(MFI)in the differential diagnosis of benign and malignant thyroid nodules. Methods Totally 50 patients with thyroid nodules examined by conventional ultrasound,MFI,and contrast-enhanced ultrasound and confirmed by histological or cytological pathology in the First Medical Center of Chinese PLA General Hospital from May to December in 2020 were enrolled in the study.The clinical data and ultrasound images were retrospectively analyzed.A binary logistic regression model was established to evaluate the performance of the model in predicting benign and malignant thyroid nodules. Results Logistic regression showed that composition and "S-W-C" sign were independent risk factors for predicting malignant thyroid nodule.The sensitivity,specificity,and Youden index of the logistic regression model were 73.33%,80.00%,and 0.53,respectively,and the area under receiver operating characteristic curve was 0.799(95% CI =0.662-0.899). Conclusion MFI facilitates the differential diagnosis of benign and malignant thyroid nodules and has the potential to be applied in the future.

Objective: Breast cancer is one of the most common malignant tumors in women and shows a rising incidence at younger ages. Therefore, early diagnosis is of great significance for treatment and prognosis. This study aimed to compare the value of ultrasound elastography (UE) combined with contrast-enhanced ultrasound (CEUS) and micro-flow imaging (MFI) in differential diagnosis of benign and malignant lesions of the breast., Methods: The sonographic characteristics of UE and CEUS as well as the vascular characteristics of MFI of 109 breast lesions categorized as Breast Imaging Reporting and Data System (BI-RADS) category 4, confirmed by surgical or biopsy pathology were retrospectively analyzed. Receiver operating characteristic (ROC) curves were used to compare the diagnostic efficacy of the three examination modalities, either alone or in combination., Results: Of the 109 breast lesions, 78 lesions were pathologically diagnosed as malignant and 31 as benign. At diagnosis, the area under the ROC curve (AUC), sensitivity, specificity, and accuracy of UE were 0.8495, 65.38%, 83.87% and 83.34%, respectively. The AUC, sensitivity, specificity and accuracy of MFI were 86.29%, 70.51%, 87.10% and 85.56%, respectively. The AUC, sensitivity, specificity and accuracy of CEUS were 90.84%, 88.46%, 74.19% and 89.16%, respectively. The AUC, sensitivity, specificity and accuracy of the combined diagnosis of UE, MFI, and CEUS were 93.90%, 85.90%, 90.32%, and 92.07%, respectively., Conclusions: The combination of UE, CEUS and MFI has the highest specificity and accuracy in the differential diagnosis of benign and malignant breast lesions compared to any one used singly., Competing Interests: None., (AJTR Copyright © 2021.)

Abstract: The need is well recognized for suitable reference populations for calibrating and verifying the size and concentration accuracy of particle analysis instruments for use in the measurement of suspended protein particles in biopharmaceuticals. Polystyrene bead standards are normally used as a reference material for calibrating and validating particle analyzers. However, these standards, unlike protein particles, are easily detected and do not challenge the sensitivity of optical instruments. Groups of instruments verified only with beads can still exhibit significant differences in measuring concentrations of more challenging protein particles. To minimize these and obtain consistent concentration measurements between instruments, reference populations must closely resemble protein aggregates in possessing high transparency and a refractive index close to typical protein matrix fluids. This paper describes work on evaluating a promising reference candidate and the use of this to harmonize the performance of Micro-Flow Imaging instruments. Results show that use of a suitable reference population can significantly increase measurement consistency when multiple instruments are used to characterize the same protein particle suspension. [Copyright &y& Elsevier]

Understanding the contribution of relevant factors to the analytical variability of the micro-flow imaging (MFI) technique is of prime importance because of the significance of the subvisible particulate data in biopharmaceutical product development. The current study was performed to determine the contribution of several key variables to the variability of the subvisible particle counts (e.g., day-to-day, vial-to-vial, sample-to-sample, and measurement-to-measurement variabilities) using a nested statistical analysis. The variability was measured in the <10 μm, ≥10 μm, ≥25 μm, and ≥50 μm size ranges along with the total particle count and the maximum and the mean particle size. The contribution of the vial to the variability of the subvisible particle counts was found to be greater than those of the other factors evaluated in the current study. The analytical method variability in terms of percent relative standard deviation with respect to the particle count in the <10 μm, ≥10 μm, and ≥25 μm size ranges was found to be 16%, 40%, and 44%, respectively. A thorough understanding of the contribution of key factors to the analytical variability revealed how the corresponding contribution can be minimized, that is, by increasing the number of vials, samples, and measurements. The results of the current study may be leveraged for the optimization of the analytical method or for minimization of the analytical variability with the MFI technique., (© PDA, Inc. 2020.)

Increasing interest in microalgal research calls for simple and automated tools to identify algal species' taxonomic level, examine their quality, monitor their growth, determine their size and shape, and enumerate them. We demonstrate the applicability of micro-flow imaging as an innovative tool to count algal cells and determine their shape and size, toward a future systematic species database, and biofuel applications. Ozonation was used to introduce changes in cell morphology such as cell oxidation, lysis and agglomeration, which were characterized by micro-flow imaging. Two ozone system configurations were used—batch and semi-batch—to oxidize four different Spirulina platensis samples, each presenting a different initial morphology correlated to culture growth stage, environmental conditions and hydration–dehydration of the cells. The ozone dose acted differently in each system: with the batch system (ozone dose of 5–15 mg L−1), the dominant action was breakage of spirulina filaments into smaller ones; with the semi-batch system (ozone dose up to ∼510 mg L−1), the dominant action was perforation of the cell walls and an increase in filament transparency (measured by mean intensity). The study also showed the influence of culture growth stage on ozonated spirulina count and shape analysis. Image 1 • Culture growth stage affects ozone tolerance of S. platensis filaments. • In batch ozonation system (lower ozone dose), S. platensis filaments break. • In semi-batch ozonation (higher ozone dose), S. platensis filaments perforate. • Ozonation-induced cell-wall perforation makes S. platensis filaments transparent. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the potential of two flow imaging microscopy (FIM) techniques (Micro-Flow Imaging (MFI) and FlowCAM) to determine total cell concentration and cell viability.Methods: B-lineage acute lymphoblastic leukemia (B-ALL) cells of 2 different donors were exposed to ambient conditions. Samples were taken at different days and measured with MFI, FlowCAM, hemocytometry and automated cell counting. Dead and live cells from a fresh B-ALL cell suspension were fractionated by flow cytometry in order to derive software filters based on morphological parameters of separate cell populations with MFI and FlowCAM. The filter sets were used to assess cell viability in the measured samples.Results: All techniques gave fairly similar cell concentration values over the whole incubation period. MFI showed to be superior with respect to precision, whereas FlowCAM provided particle images with a higher resolution. Moreover, both FIM methods were able to provide similar results for cell viability as the conventional methods (hemocytometry and automated cell counting).Conclusion: FIM-based methods may be advantageous over conventional cell methods for determining total cell concentration and cell viability, as FIM measures much larger sample volumes, does not require labeling, is less laborious and provides images of individual cells. [ABSTRACT FROM AUTHOR]

The present study aimed to determine the usefulness of contrast-enhanced ultrasonography (CEUS) with Sonazoid in evaluating the therapeutic response to sorafenib for hepatocellular carcinoma (HCC). In total, 26 patients with advanced HCC who received sorafenib and were followed up by CEUS were enrolled in the present study. CEUS was performed prior to and within 2-4 weeks of treatment, and the images of the target lesion in the post-vascular phase with a re-injection method were analyzed. The presence (+) or absence (-) of intratumoral necrosis and the intratumoral vascular architecture on micro-flow imaging (MFI) were compared prior to and subsequent to treatment. Target lesions that exhibited non-enhancement after re-injection were considered to indicate intratumoral necrosis. The intratumoral vascular architecture was classified into three groups, as follows: Vd, the intratumoral vessels visually narrowed or decreased; Vnc, the vessels remained unchanged; and Vi, the vessels were thickened or increased. Survival curves were estimated using the Kaplan-Meier method and compared using the log rank test between the intratumoral necrosis (+) and (-) groups, and among the Vd, Vnc and Vi groups. P<0.05 was considered to indicate a statistically significant difference. The number of patients in the intratumoral necrosis (+) and (-) groups was 8 and 18 patients, respectively, and the median survival time (MST) was 7.2 months [95% confidence interval (CI), 2.2-12.2] and 9.5 months (95% CI, 5.1-13.8), respectively (P=0.44). The MFI findings were observed in 11 patients in the Vd group, 10 patients in the Vnc group and 5 patients in the Vi group. The MSTs in the Vd, Vnc and Vi groups were 15.6 months (95% CI, 5.0-23.3), 11.0 months (95% CI, 3.5-17.6) and 3.6 months (95% CI: 1.2-6.0), respectively. The P-value for the differences between the Vd and Vnc groups, Vd and Vi groups, and Vnc and Vi groups were 0.78, 0.016 and 0.047, respectively, which indicated that the survival time decreased significantly in the Vi group. Evaluation of intratumoral vascular architecture using MFI demonstrates promise for assessing the therapeutic response to sorafenib in patients with HCC.

Unlabelled: The purpose of this work was to investigate the susceptibility of an aluminum adjuvant and an aluminum-adjuvanted native outer membrane vesicle (nOMV) vaccine formulation to freeze/thaw-induced agglomeration using static light scattering and micro-flow Imaging analysis; and to evaluate the use of propylene glycol as a vaccine formulation excipient by which freeze/thaw-induced agglomeration of a nOMV vaccine formulation could be mitigated. Our results indicate that including 7% v/v propylene glycol in an nOMV containing aluminum adjuvanted vaccine formulation, mitigates freeze/thaw-induced agglomeration., Lay Abstract: We evaluated the effect of freeze-thawing on an aluminum adjuvant and an aluminum adjuvanted native outer membrane vesicle (nOMV) vaccine formulation. Specifically, we characterized the freeze/thaw-induced agglomeration through the use of static light scattering, micro-flow imaging, and cryo-electron microscopy analysis. Further, we evaluated the use of 0-9% v/v propylene glycol as an excipient which could be included in the formulation for the purpose of mitigating the agglomeration induced by freeze/thaw. The results indicate that using 7% v/v propylene glycol as a formulation excipient is effective at mitigating agglomeration of the nOMV vaccine formulation, otherwise induced by freeze-thawing., (© PDA, Inc. 2015.)

It is considered difficult to make a definitive diagnosis of focal nodular hyperplasia (FNH) of <3 cm when using conventional diagnostic imaging modalities. Typical FNH imaging findings are: i) central scar formation, ii) nutrient vessels extending radially from the center and iii) the presence of Kupffer cells. In a clinical setting, identification of a spoke-wheel pattern formed by nutrient vessels extending radially is a key feature in the diagnosis of FNH. In this study, we investigated the detection rate of spoke-wheel patterns of FNH <3 cm using arrival time parametric imaging (At-PI) technology with Sonazoid-enhanced ultrasonography (US). Five patients with FNH <3 cm who had undergone Sonazoid-enhanced US at the Toho University Omori Medical Center between February 2008 and March 2009 were included in the study. The mean tumor diameter was 20.2±7.2 mm. Lesions were enhanced with 0.5 ml Sonazoid US contrast agent and a video of the procedure was saved and used for At-PI analysis of contrast agent dynamics in FNH. Three ultrasonographic specialists examined the images and made a diagnosis of FNH based on the findings of spoke-wheel patterns. Similarly, micro-flow imaging (MFI) was performed to evaluate the contrast agent dynamics in FNH. Using MFI, FNH was diagnosed in 3 of the 5 cases by the three specialists, whereas At-PI enabled the identification of spoke-wheel patterns in all 5 cases. At-PI using Sonazoid-enhanced US is superior for detecting spoke-wheel patterns of FNH <3 cm.

Computer-aided diagnosis (CAD) has become one of the major research subjects in medical imaging and diagnostic radiology. The basic concept of CAD is to provide computer output as a second opinion to assist radiologists' image interpretations by improving the accuracy and consistency of radiologic diagnosis and also by reducing the image-reading time. To date, research on CAD in ultrasound (US)-based diagnosis has been carried out mostly for breast lesions and has been limited in the fields of gastroenterology and hepatology, with most studies being conducted using B-mode US images. Two CAD schemes with contrast-enhanced US (CEUS) that are used in classifying focal liver lesions (FLLs) as liver metastasis, hemangioma, or three histologically differentiated types of hepatocellular carcinoma (HCC) are introduced in this article: one is based on physicians' subjective pattern classifications (subjective analysis) and the other is a computerized scheme for classification of FLLs (quantitative analysis). Classification accuracies for FLLs for each CAD scheme were 84.8% and 88.5% for metastasis, 93.3% and 93.8% for hemangioma, and 98.6% and 86.9% for all HCCs, respectively. In addition, the classification accuracies for histologic differentiation of HCCs were 65.2% and 79.2% for well-differentiated HCCs, 41.7% and 50.0% for moderately differentiated HCCs, and 80.0% and 77.8% for poorly differentiated HCCs, respectively. There are a number of issues concerning the clinical application of CAD for CEUS, however, it is likely that CAD for CEUS of the liver will make great progress in the future.