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Optically induced dielectrophoresis (ODEP) is effective for cell manipulation. However, its utilization has been limited by the requirement of solution with low conductivity. This issue has been ignored in ODEP-relevant studies. To address this issue, this study aims to investigate to what extent the cell viability and performance of ODEP-based cell manipulation are affected by low conductivity conditions. Additionally, this study aims to modify sucrose solutions to reduce the impacts caused by low-conductivity solutions. Results revealed the use of sucrose solution in ODEP operation could significantly reduce the viability of the manipulated cells by 9.1 and 38.5% after 2- and 4-h incubation, respectively. Prolonged operation time (e.g., 4 h) in sucrose solution could lead to significantly inferior performance of cell manipulation, including 47.2% reduction of ODEP manipulation velocity and 44.4% loss of the cells manipulatable by ODEP. The key finding of this study is that the use of bovine serum albumin (BSA)-supplemented sucrose solution (conductivity: 25–50 μS cm−1) might significantly increase the cell viability by 10.9–14.8% compared with that in sucrose solution after 4 h incubation. Moreover, the ODEP manipulation velocity of cells in the BSA-supplemented sucrose solution (conductivity: 25 μS cm−1) was comparable to that in sucrose solution during 4-h incubation. More importantly, compared with sucrose solution, the use of BSA-supplemented sucrose solution (conductivity: 25–50 μS cm−1) contributed high percentage (80.4–93.5%) of the cells manipulatable by ODEP during 4-h incubation. Overall, this study has provided some fundamental information relevant to the improvement of background solutions for ODEP-based cell manipulation.

The heterogeneity of the drug resistance of cancer cells in a tumor is regarded as an important cause of therapeutic resistance and thus treatment failure. An understanding of the heterogeneity of cancer cells in a tumor in terms of their anti-cancer drug resistance is of great value for clinical applications or fundamental studies. To achieve this goal, a combination of cell-based drug testing and optically induced dielectrophoresis (ODEP)-based cell manipulation for sorting, separation, and isolation of drug-treated cells with various degrees of cell viability is proposed. For the latter, the key working principle is based on the difference in the ODEP force generated on the cells with various degrees of viability. To test the proposed idea, an ODEP microfluidic system was designed and fabricated in which two types of ODEP-based cell manipulation schemes were tested. The results successfully demonstrated that the proof-of-concept and practical application schemes were capable of effectively sorting, separating, and isolating doxorubicin-treated Dx5 (i.e., cells with drug resistance) and MES-SA (i.e., cells without drug resistance) cells that exhibited various degrees of viability and levels of anti-cancer drug resistance gene (i.e., ABCB1) expression. Moreover, the results also demonstrated that the proposed technique was capable of sorting and separating cell of the same type (i.e., drug-treated Dx5 cells) but different degrees of viability and anti-cancer drug resistance gene expression levels. Overall, this study presents a technique that is able to effectively sort, separate, and isolate drug-treated cancer cells with phenotypic heterogeneity for subsequent clinical applications or fundamental studies.

Background The goal of this study was to investigate the prognostic factors for locoregional recurrence and metastasis in patients with cutaneous melanoma (CM) who underwent surgery, especially in the acral lentiginous melanoma (ALM) subtype. Methods This study was a retrospective review of patients who underwent surgery for CM at Taipei Veterans General Hospital between 2000 and 2018. We investigated the risk factors for locoregional and distant metastases. The association between clinicopathological factors and locoregional recurrence and distant metastasis of the CM and ALM subtypes was analyzed. In addition, the outcomes between the ALM and non-ALM groups were compared. Results A total of 161 patients were included in the analysis. The most common histological subtype was ALM. The overall locoregional recurrence rate of CM was 13.0% and the distant metastasis rate was 42.9%, whereas that of the ALM subtype was 12.5% and 45.5%, respectively. In patients with CM, male sex, tumor with lymphovascular invasion, and positive lymph node status were the prognostic factors for both locoregional recurrence and distant metastasis. Among the patients with ALM, positive lymph node status was significantly associated with both locoregional recurrence and distant metastasis. Conclusion In this cohort, factors influencing locoregional recurrence and distant metastasis were similar between the ALM and non-ALM groups. The above-recommended surgical margin did not show any benefit in either the CM or the ALM subtype. ALM can be handled using the same surgical strategy as CM in the Asian population.

Simple Summary Information describing circulating tumor cells (CTCs) holds promise for clinical applications. However, conventional CTCs enumeration could ignore the CTCs more relevant to cancer metastasis. Thus, negative selection CTC enumeration was proposed, by which information on the numbers of CTCs and CD45neg EpCAMneg cells can be obtained. By combining this approach with the conventional biomarker carcinoembryonic antigen (CEA), this study aimed to explore whether any combination of these biomarkers could improve the predictive performance for colorectal cancer (CRC) or its status. Results revealed that a combination of the two cell populations showed improved performance (AUROC: 0.893) for CRC prediction over the use of only one population. Compared with CEA alone, the combination of the three biomarkers increased the performance (AUROC) for advanced CRC prediction from 0.643 to 0.727. Compared with that of CEA alone for metastatic CRC prediction, the AUROC was increased from 0.780 to 0.837 when the CTC count was included. Abstract Conventional circulating tumor cell (CTC) enumeration could ignore the CTCs more relevant to cancer metastasis. Thus, negative selection CTC enumeration was proposed, by which information on two cellular biomarkers (numbers of CTCs and CD45neg EpCAMneg cells) can be obtained. By combining this approach with the conventional biomarker carcinoembryonic antigen (CEA), this study aimed to explore whether any combination of these biomarkers could improve the predictive performance for colorectal cancer (CRC) or its status. In this work, these two cell populations in healthy donors and CRC patients were quantified. Results revealed that enumeration of these two cell populations was able to discriminate healthy donors from CRC patients, even patients with non-advanced CRC. Moreover, the combination of the two cell populations showed improved performance (AUROC: 0.893) for CRC prediction over the use of only one population. Compared with CEA alone, the combination of the three biomarkers increased the performance (AUROC) for advanced CRC prediction from 0.643 to 0.727. Compared with that of CEA alone for metastatic CRC prediction, the AUROC was increased from 0.780 to 0.837 when the CTC count was included. Overall, this study demonstrated that the combination of these two cellular biomarkers with CEA improved the predictive performance for CRC and its status.

Negative selection-based circulating tumor cell (CTC) isolation is able to harvest viable, label-free, and clinically meaningful CTCs from the cancer patients' blood. Nevertheless, its main shortcoming is its inability to isolate high-purity CTCs, restricting subsequent CTC-related analysis. To address this issue, this study proposed a two-step optically-induced dielectrophoresis (ODEP) cell manipulation to process the cell sample harvested by negative selection-/immunomagnetic microbeads-based CTC isolation. The working mechanism is that the ODEP force acting on the cells with and without magnetic microbeads binding is different. Accordingly, the use of ODEP cell manipulation in a microfluidic system was designed to first separate and then isolate the cancer cells from other magnetic microbead-bound cells. Immunofluorescent microscopic observation and ODEP cell manipulation were then performed to refine the purity of the cancer cells. In this study, the optimum operating conditions for effective cell isolation were determined experimentally. The results revealed that the presented method was able to further refine the purity of cancer cell in the sample obtained after negative selection-based CTC isolation with high cell purity (81.6~86.1%). Overall, this study proposed the combination of immunomagnetic bead-based cell isolation and ODEP cell manipulation for the negative selection-based isolation of CTCs.

Cell manipulation using optically induced dielectrophoresis (ODEP) in microfluidic systems has attracted the interest of scientists due to its simplicity. Although this technique has been successfully demonstrated for various applications, one fundamental issue has to be addressed&mdash, Whether, the ODEP field affects the native properties of cells. To address this issue, we explored the effect of ODEP electrical conditions on cellular properties. Within the experimental conditions tested, the ODEP-based cell manipulation with the largest velocity occurred at 10 Vpp and 1 MHz, for the two cancer cell types explored. Under this operating condition, however, the cell viability of cancer cells was significantly affected (e.g., 70.5 &plusmn, 10.0% and 50.6 &plusmn, 9.2% reduction for the PC-3 and SK-BR-3 cancer cells, respectively). Conversely, the exposure of cancer cells to the ODEP electrical conditions of 7&ndash, 10 Vpp and 3&ndash, 5 MHz did not significantly alter the cell viability, cell metabolic activity, and the EpCAM, VIM, and ABCC1 gene expression of cancer cells. Overall, this study fundamentally investigated the effect of ODEP electrical conditions on the cellular properties of cancer cells. The information obtained is crucially important for the utilization of ODEP-based cell manipulation in a microscale system for various applications.

Background/Purpose House dust mite (HDM) is well known as one of the major indoor allergens that trigger allergic inflammation, especially asthma, and accounts for 85% of all cases. So far, asthma has been thought of as a condition of imbalance between T helper (Th)1 and Th2. Fungal immunomodulatory protein- Flammulina velutipes (FIP-fve) has been seemingly demonstrated to modulate the response to Th1 cytokine production. The aim of this study was to investigate if the oral administration of FIP-fve can inhibit HDM-induced asthma inflammation in the mouse model. Methods We divided the mice (female BALB/c, 4–6 weeks) into four groups: the prevention group, which consisted of mice sensitized by HDM (intraperitoneally on Day 1, Day 7, and Day 14, and intranasally on Day 14, Day 17, Day 21, Day 24, and Day 27) fed with FIP-fve from Day 1 to Day 14; the treatment group, which comprised mice that received treatment from Day 14 to Day 28; the positive control (PC, sensitized by HDM fed without FIP-fve) group; and the negative control group (NC, nonsensitized). Airway hyperresponsiveness induced by methacholine challenge was determined using whole-body barometric plethysmography. In addition, cytokines were analyzed from bronchoalveolar lavage fluid and serum. Histopathological studies and Liu's staining method in mice lungs were also performed. Results The results showed that both pre- and posttreated FIP-fve groups had significantly reduced airway hyperresponsiveness compared with the PC group after methacholine challenge. In addition, a significantly decreased level of HDM-specific immunoglobulin E in serum and decreased production of Th2 cytokines in bronchoalveolar lavage fluid and serum were observed in these two FIP-fve fed groups. Moreover, more decreased amounts of infiltrating inflammatory cells were present in the lungs of FIP-fve fed groups than those of the PC group. Conclusion Oral FIP-fve had an anti-inflammatory effect on the acute phase of the airway inflammatory process induced by HDM in the mouse model and might have a potentially therapeutic role for allergic airway diseases.

Neonatal adrenal hemorrhage (NAH) is rare and is found in only 0.2% of newborns. Scrotal hematoma (SH) in newborns is also rare. NAH associated with SH is extremely rare, with only 29 cases reported in the literature. Herein, we report a baby boy who presented with SH; after ultrasonography examinations, the diagnosis of NAH associated with SH was made. He received conservative treatment only. From our experience and that of others, appropriate integration of clinical information, physical examination and the results of abdominal and scrotal ultrasonography can achieve the accurate diagnosis of NAH associated with SH. This association allows conservative treatment that avoids unnecessary surgical exploration.