Pumpless, selective docking of yeast cells inside a microfluidic channel induced by receding meniscus

We present a simple cell docking method induced by receding meniscus to capture non-adherent yeast cells onto microwells inside a microfluidic channel. Microwells were fabricated either by capillary moulding of UV curable polyurethane acrylate (PUA) onto glass substrate or direct replica moulding of poly(dimethyl siloxane) (PDMS). A cell suspension of the budding yeast, Saccharomyces cerevisiae, was introduced into the microfluidic channel by surface tension driven capillary flow and a receding meniscus was subsequently generated by evaporation. As the meniscus progressed, one to multiple yeast cells were spontaneously captured onto microwells by lateral capillary force created at the bottom of the meniscus. Using this cell-based platform, we observed the response of yeast cells upon stimulation by a mating pheromone (alpha-factor) by monitoring the expression of green fluorescent protein (GFP) with time. It was observed that alpha-factor triggered the expression of GFP at 60 min after stimulation and the fluorescence intensity was sustained for an additional 60 min without changes.This work was supported by the Micro Thermal System Research Center of Seoul National University and the Ministry of Science and Technology through Bio Tool R&D Project for Cell Research. This work was also supported in part by the SRC program of MOST/KOSEF (R11-2005-009-02004-0) to S.-H. P

Soft lithography for microfluidics: a review

Soft lithography has provided a low-expertise route toward micro/nanofabrication and is playing an important role in microfluidics, ranging from simple channel fabrication to the creation of micropatterns onto a surface or within a microfluidic channel. In this review, the materials, methods, and applications of soft lithography for microfluidics are briefly summarized with a particular emphasis on integrated microfluidic systems containing physical microstructures or a topographically patterned substrate. Relevant exemplary works based on the combination of various soft lithographic methods using microfluidics are introduced with some comments on their merits and weaknesses.This work was supported by Korea Science and Engineering Foundation (KOSEF) grant funded by the Korea government (MOST) (R01-2007-000- 20675-0) and the Grant-in-Aid for Next-Generation New Technology Development Programs from the Korea Ministry of Commerce, Industry and Energy (No.10030046). This work was also supported by the Korea Research Foundation Grant funded by the Korean Government (MOEHRD, Basic Research Promotion Fund)(KRF-2007-331-D00064) for Sun Min Kim

Roles of endothelial A-type lamins in migration of T cells on and under endothelial layers

Stiff nuclei in cell-dense microenvironments may serve as distinct biomechanical cues for cell migration, but such a possibility has not been tested experimentally. As a first step addressing this question, we altered nuclear stiffness of endothelial cells (ECs) by reducing the expression of A-type lamins using siRNA, and investigated the migration of T cells on and under EC layers. While most T cells crawling on control EC layers avoided crossing over EC nuclei, a significantly higher fraction of T cells on EC layers with reduced expression of A-type lamins crossed over EC nuclei. This result suggests that stiff EC nuclei underlying T cells may serve as "duro-repulsive" cues to direct T cell migration toward less stiff EC cytoplasm. During subendothelial migration under EC layers with reduced expression of A-type lamins, T cells made prolonged contact and substantially deformed EC nuclei, resulting in reduced speed and directional persistence. This result suggests that EC nuclear stiffness promotes fast and directionally persistent subendothelial migration of T cells by allowing minimum interaction between T cells and EC nuclei.open11102sciescopu

Safety and Efficacy of Second-Generation Everolimus-Eluting Xience V Stents Versus Zotarolimus-Eluting Resolute Stents in Real-World Practice Patient-Related and Stent-Related Outcomes From the Multicenter Prospective EXCELLENT and RESOLUTE-Korea Registries

ObjectivesThis study sought to compare the safety and efficacy of the Xience V/Promus everolimus-eluting stent (EES) (Abbott Vascular, Temecula, California) with the Endeavor Resolute zotarolimus-eluting stent (ZES-R) (Medtronic Cardiovascular, Santa Rosa, California) in “all-comer” cohorts.BackgroundOnly 2 randomized controlled trials have compared these stents.MethodsThe EXCELLENT (Efficacy of Xience/Promus Versus Cypher to Reduce Late Loss After Stenting) and RESOLUTE-Korea registries prospectively enrolled 3,056 patients treated with the EES and 1,998 patients treated with the ZES-R, respectively, without exclusions. Stent-related composite outcomes (target lesion failure [TLF]) and patient-related composite outcomes were compared in crude and propensity score-matched analyses.ResultsOf 5,054 patients, 3,830 (75.8%) had off-label indication (2,217 treated with EES and 1,613 treated with ZES-R). The stent-related outcome (82 [2.7%] vs. 58 [2.9%], p = 0.662) and the patient-related outcome (225 [7.4%] vs. 153 [7.7%], p = 0.702) did not differ between EES and ZES-R, respectively, at 1 year, which was corroborated by similar results from the propensity score-matched cohort. The rate of definite or probable stent thrombosis (18 [0.6%] vs. 7 [0.4%], p = 0.306) also was similar. In multivariate analysis, off-label indication was the strongest predictor of TLF (adjusted hazard ratio: 2.882; 95% confidence interval: 1.226 to 6.779; p = 0.015).ConclusionsIn this robust real-world registry with unrestricted use of EES and ZES-R, both stents showed comparable safety and efficacy at 1-year follow-up. Overall incidences of TLF and definite stent thrombosis were low, even in the patients with off-label indication, suggesting excellent safety and efficacy of both types of second-generation drug-eluting stents

Littoral Cell Angioma (LCA) Associated with Liver Cirrhosis

A littoral cell angioma (LCA) is a rare benign vascular tumor of the spleen. A 60-year-old man, with multiple nodules in imaging study and liver cirrhosis graded as Child-Pugh classification class A, was transferred for splenomegaly. A thrombocytopenia was found on hematological evaluation. Because there was no evidence of hematological and visceral malignancy, a splenectomy was performed for a definitive diagnosis. The histological and immunohistochemical features of the splenic specimens were consistent with a LCA. After the splenectomy, the thrombocytopenia recovered to the normal platelet count. There has been no previous report of a LCA combined with liver cirrhosis. Herein, the first case of a LCA in Korea, diagnosed and treated by a splenectomy, is reported

Retrospective analyses of cisplatin-based doublet combination chemotherapy in patients with advanced gastric cancer

<p>Abstract</p> <p>Backgrounds</p> <p>Cisplatin-based chemotherapy, in combination with fluoropyrimidines or taxanes, have demonstrated efficacy against advanced gastric cancer (AGC). This retrospective study was performed with the data obtained from our cancer chemotherapy registry and eight another cancer centers.</p> <p>Methods</p> <p>In 2008, a total of 283 AGC patients were treated with cisplatin-based doublet chemotherapy in the first-line setting: capecitabine plus cisplatin (XP, n = 77), S-1 plus cisplatin (SP, n = 97), taxanes (docetaxel, paclitaxel) plus cisplatin (TP, n = 72), and 5-fluorouracil plus platinum (FP, n = 37). The primary endpoint of this study was overall survival (OS) and the secondary endpoints were safety, response rate and progression-free survival (PFS).</p> <p>Results</p> <p>The median age was 54 years with a range of 28-78 years and median delivered number of chemotherapy cycles were XP: 4, SP: 5, TP: 5 and FP: 5, respectively. Objective tumor responses (38%; 95% CI, 32-43%) were 40% for XP, 42% for SP, 36% for DP, and 24% for FP. The estimated median PFS was 4.5 months (95% CI, 3.6-5.4 months) and the median OS was 12.3 months (95% CI, 10.8-13.7 months). No statistically significant difference was found between each regimen used as first-line chemotherapy. At multivariate analysis, independent prognostic parameters for OS were prior gastrectomy, peritoneal dissemination, performance status and hemoglobin level</p> <p>Conclusion</p> <p>All of the cisplatin-based doublet chemotherapy regimens appear to be active as first-line chemotherapy for AGC. With better patient selection according to clinical parameters and molecular markers, clinical outcomes of AGC patients in first-line setting can be improved.</p

Multicenter retrospective analysis of 581 patients with primary intestinal non-hodgkin lymphoma from the Consortium for Improving Survival of Lymphoma (CISL)

<p>Abstract</p> <p>Background</p> <p>Primary intestinal non-Hodgkin lymphoma (NHL) is a heterogeneous disease with regard to anatomic and histologic distribution. Thus, analyses focusing on primary intestinal NHL with large number of patients are warranted.</p> <p>Methods</p> <p>We retrospectively analyzed 581 patients from 16 hospitals in Korea for primary intestinal NHL in this retrospective analysis. We compared clinical features and treatment outcomes according to the anatomic site of involvement and histologic subtypes.</p> <p>Results</p> <p>B-cell lymphoma (n = 504, 86.7%) was more frequent than T-cell lymphoma (n = 77, 13.3%). Diffuse large B-cell lymphoma (DLBCL) was the most common subtype (n = 386, 66.4%), and extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) was the second most common subtype (n = 61, 10.5%). B-cell lymphoma mainly presented as localized disease (Lugano stage I/II) while T-cell lymphomas involved multiple intestinal sites. Thus, T-cell lymphoma had more unfavourable characteristics such as advanced stage at diagnosis, and the 5-year overall survival (OS) rate was significantly lower than B-cell lymphoma (28% versus 71%, P < 0.001). B symptoms were relatively uncommon (20.7%), and bone marrow invasion was a rare event (7.4%). The ileocecal region was the most commonly involved site (39.8%), followed by the small (27.9%) and large intestines (21.5%). Patients underwent surgery showed better OS than patients did not (5-year OS rate 77% versus 57%, P < 0.001). However, this beneficial effect of surgery was only statistically significant in patients with B-cell lymphomas (P < 0.001) not in T-cell lymphomas (P = 0.460). The comparison of survival based on the anatomic site of involvement showed that ileocecal regions had a better 5-year overall survival rate (72%) than other sites in consistent with that ileocecal region had higher proportion of patients with DLBCL who underwent surgery. Age > 60 years, performance status ≥ 2, elevated serum lactate dehydrogenase, Lugano stage IV, presence of B symptoms, and T-cell phenotype were independent prognostic factors for survival.</p> <p>Conclusions</p> <p>The survival of patients with ileocecal region involvement was better than that of patients with involvement at other sites, which might be related to histologic distribution, the proportion of tumor stage, and need for surgical resection.</p