• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.4
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• pp.15-20
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• 2009

In a detection system based on laser light scattering, focusing an excitation laser beam into a focal point of a channel in a microfluidic chip is important for obtaining the highest excitation intensity, and consequently for obtaining a laser light scattering signal using a photodetector with a high efficiency. In this paper, we present a polydimethylsiloxane (PDMS) microfluidic chip consisting of an integrated PDMS microlens for cell detection based on laser light scattering. We fabricated PDMS microlens for optical detection system by simply putting down on PDMS chips. The PDMS microlens was fabricated by photoresist reflow and replica molding. This fabrication technique is simple and has an excellent property in terms of the microlens and a high-dimensional accuracy. The PDMS microlens integrated on the PDMS microfluidic chip has been verified to improve the laser intensity, and accordingly, the signal-to-noise ratio and sensitivity of laser light scattering detection for red blood cells(RBCs)

• Tuberculosis and Respiratory Diseases
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• v.74 no.3
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• pp.134-139
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• 2013

Splenosis is defined as an autotransplantation of the splenic tissue after splenic rupture or splenectomy, and occurs most frequently in the peritoneal cavity. Splenosis is usually asymptomatic and is found incidentally. We report a case of combined intrathoracic and intraperitoneal splenosis in a 54-year-old male who worked as a miner for 10 years in his twenties, and was a current smoker. He was referred to our hospital for further evaluation of an incidental left diaphragmatic mass. Positron emission tomography-computed tomography and bronchoscopy were performed to evaluate the possibility of malignancy. There was no evidence of malignancy, but the spleen was not visualized. Reviewing his medical history revealed previous splenectomy, following a dynamite explosion injury. Therefore, splenosis was suspected and technetium-99m-labeled heat-damaged red blood cell scan confirmed the diagnosis. Radionuclide imaging is a useful diagnostic tool for splenosis, which could avoid unnecessary invasive procedures.

• The Journal of Internal Korean Medicine
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• v.33 no.2
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• pp.197-208
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• 2012

Objectives : Gleditsiae Spina has the effects of expelling toxins, draining pus, invigorating blood and resolving abscesses. Some clinicians apply the herb for patients suffering from cancer. However, its anti-cancer activities are not well understood. In the present study, anti-tumor agents from Gleditsiae Spina were purified. Methods : The viability of the PC-3 cell line was determined using MTT assay, and the induction of apoptosis by Gleditsiae Spina extract in PC-3 cells was measured by Annexin-V/propidium iodide double staining assay detected by flow cytometry. TLC and HPLC analysis were used to separate and identify the anti-cancer agents. Results : Treatment of the extract resulted in significant decreased cell viability of PC-3 cells in a dose- and time-dependent manner. Dose-dependent apoptotic cell death was also measured by flow cytometry analysis. The anti-cancer agents were successfully separated and identified by using TLC and HPLC analysis and the most potential agent among them was separated from EtOAC fraction. Conclusions : These results might be applied in developing new drugs from natural resources like Korean traditional medicine, and also support the clinical usefulness of herbal medicine.

• Toxicological Research
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• v.28 no.1
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• pp.57-65
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• 2012

In this study, the 4-week oral toxicity and anti-cancer activity of the hexane layer of Melia azedarach L. var. japonica Makino's bark extract were investigated. We carried out a hollow fiber (HF) assay and 28-day repeated toxicity study to confirm the anti-cancer effect and safety of the hexane layer. The HF assay was carried out using an A549 human adenocarcinoma cell via intraperitoneal (IP) site with or without cisplatin. In the result, the 200 mg/kg b.w of hexane layer with 4 mg/kg b.w of cisplatin treated group, showed the highest cytotoxicity aginst A549 carcinoma cells. For the 28-day repeated toxicity study, 6 groups of 10 male and female mice were given by gavage 200, 100, or 50 mg/kg b.w hexane layer with or without 4 mg/kg b.w of cisplatin against body weight, and were then sacrificed for blood and tissue sampling. The subacute oral toxicity study in mice with doses of 200, 100, and 50 mg/kg b.w hexane layer showed no significant changes in body weight gain and general behavior. The cisplatin-treated group significantly decreased in body weight compared to the control group but regained weight with 100 and 200 mg/kg b.w of hexane layer. The biochemical analysis showed significant increase in several parameters (ALT, total billirubin, AST, creatinine, and BUN) in cisplatin-treated groups. However, in the group given a co-treatment of hexane layer (200 mg/kg b.w), levels of these parameters decreased. In hematological analysis, cisplatin induced the reduction of WBCs and neutrophils but co-treatment with hexane layer (100 and 200 mg/kg b.w) improved these toxicities caused by cisplatin. The histological profile of the livers showed eosinophilic cell foci in central vein and portal triad in cisplatin treated mice. These results show that hexane layer might have an anti-cancer activity and could improve the toxicity of cisplatin.

• Molecules and Cells
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• v.41 no.11
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• pp.971-978
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• 2018

The stem cell factor (SCF)/c-KIT axis plays an important role in the hematopoietic differentiation of human pluripotent stem cells (hPSCs), but its regulatory mechanisms involving microRNAs (miRs) are not fully elucidated. Here, we demonstrated that supplementation with SCF increases the hematopoietic differentiation of hPSCs via the interaction with its receptor tyrosine kinase c-KIT, which is modulated by miR-221 and miR-222. c-KIT is comparably expressed in undifferentiated human embryonic and induced pluripotent stem cells. The inhibition of SCF signaling via treatment with a c-KIT antagonist (imatinib) during hPSC-derived hematopoiesis resulted in reductions in the yield and multi-lineage potential of hematopoietic progenitors. We found that the transcript levels of miR-221 and miR-222 targeting c-KIT were significantly lower in the pluripotent state than they were in terminally differentiated somatic cells. Furthermore, suppression of miR-221 and miR-222 in undifferentiated hPSC cultures induced more hematopoiesis by increasing c-KIT expression. Collectively, our data implied that the modulation of c-KIT by miRs may provide further potential strategies to expedite the generation of functional blood cells for therapeutic approaches and the study of the cellular machinery related to hematologic malignant diseases such as leukemia.

• ALGAE
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• v.31 no.1
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• pp.17-31
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• 2016

To explore the feeding ecology of the newly described heterotrophic dinoflagellate Aduncodinium glandula in the family Pfiesteriaceae, its feeding behavior and prey species were investigated. Additionally, the growth and ingestion rates of A. glandula on the mixotrophic dinoflagellates Heterocapsa triquetra and Akashiwo sanguinea, its optimal and suboptimal prey, respectively were measured. A. glandula fed on prey through a peduncle after anchoring to the prey using a tow filament. A. glandula ate all algal prey and perch blood cells tested and had the most diverse prey species in the family Pfiesteriaceae. Unlike for other pfiesteriacean species, H. triquetra and A. sanguinea support the positive growth of A. glandula. However, the cryptophytes Rhodomonas salina and Teleaulax sp. and the phototrophic dinoflagellate Amphidinium carterae did not support the positive growth of A. glandula. Thus, A. glandula may have a unique kind of prey and its optimal prey differs from that of the other pfiesteriacean dinoflagellates. With increasing mean prey concentration, the growth rates of A. glandula on H. triquetra and A. sanguinea increased rapidly and then slowed or became saturated. The maximum growth rates when feeding on H. triquetra and A. sanguinea were 1.004 and 0.567 d⁻¹, respectively. Further, the maximum ingestion rates of A. glandula on H. triquetra and A. sanguinea were 0.75 and 1.38 ng C predator⁻¹ d⁻¹, respectively. There is no other pfiesteriacean species having H. triquetra and A. sanguinea as optimal and suboptimal prey. Thus, A. glandula may be abundant during blooms dominated by these species not preferred by the other pfiesteriacean dinoflagellates.

• Childhood Kidney Diseases
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• v.15 no.2
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• pp.107-115
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• 2011

Acute kidney injury (AKI) is associated with mortality and may lead to increased medical expense. A modified criteria (pediatric RIFLE [pRIFLE]: Risk, Injury, Failure, Loss, and End-stage renal disease) has been proposed to standardize the definition of AKI. The common causes of AKI are renal ischemia, nephrotoxic medications, and sepsis. A majority of critically ill children develop AKI by the pRIFLE criteria and need to receive intensive care early in the course of AKI. Factors influencing patient survival (pediatric intensive care unit discharge) are known to be low blood pressure at the onset of renal replacement therapy (RRT), the use of vasoactive pressors during RRT, and the degrees of fluid overload at the initiation of RRT. Early intervention of continuous RRT (CRRT) has been introduced to reduce mortality and fluid overload that affects poor prognosis in patients with AKI. Here, we briefly review the practical prescription of pediatric CRRT and literatures on the outcomes of patients with AKI receiving CRRT and associations among AKI, fluid overload, and CRRT. In conclusion, we suggest that an increased emphasis should be placed on the early initiation of CRRT and fluid overload in the management of pediatric AKI.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4327-4333
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• 2016

Purpose: To systematically review efficacyand safety of robotic gastrectomy (RG) compared with conventional laparoscopic gastrectomy (LG) for gastric carcinoma. Materials and Methods: A systematic literature search was carried out using PubMed, Cochrane Library, CBM, CNKI, WanFang, VIP and other sources like relevant references to obtain comparative studies assessing the effectiveness and safety between RG and LG published between 2013 and 2016. Then the literature was screened and the data were extracted by 2 independent reviewers. The quality of the literature was assessed, and the data analyzed using Stata/SE 14 software. Fixed effects or random effects models wereapplied according to heterogeneity. Results: A total of 12 non-randomized observational clinical studies involving 3,580 patients were included, of which 1,096 had undergone RG and 2,484 had received LG. The results of the meta-analysis showed in terms of effectiveness, RG was associated with less blood loss, less time to first flatus and greater number of harvested lymph nodes, but there were no significant differences in proximal and distal resection margins, compared with LG. In terms of efficiency, RG was associated with shorter hospital stay, but longer operative time. In terms of safety, there were no statistically significant differences in complications, mortality and conversions between RG and LG. Conclusions: RG can achieve comparable or better short-term and radical effects than LG, with respect to effectiveness, efficiency and safety in treatment of gastric carcinoma. Future studies involving RG should focus on decreasing operative time and reducing cost. Moreover, there is a need for randomized controlled trials comparing the two techniques with long-term follow-up.

• Journal of the Optical Society of Korea
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• v.20 no.1
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• pp.78-87
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• 2016

Red blood cells (RBCs) are customarily adhered to a bio-functionalised substrate to make them stationary in interferometric phase-imaging modalities. This can make them susceptible to receive alterations in innate morphology due to their own weight. Optical tweezers (OTs) often driven by Gaussian profile of a laser beam is an alternative modality to overcome contact-induced perturbation but at the same time a steeply focused laser beam might cause photo-damage. In order to address both the photo-damage and substrate adherence induced perturbations, we were motivated to stabilize the RBC in OTs by utilizing a laser beam of ‘arbitrary intensity profile’ generated by a source having cavity imperfections per se. Thus the immobilized RBC was investigated for phase-imaging with sinusoidal interferograms generated by a compact and robust Michelson interferometer which was designed from a cubic beam splitter having one surface coated with reflective material and another adjacent coplanar surface aligned against a mirror. Reflected interferograms from bilayers membrane of a trapped RBC were recorded and analyzed. Our phase-imaging set-up is limited to work in reflection configuration only because of the availability of an upright microscope. Due to RBC’s membrane being poorly reflective for visible wavelengths, quantitative information in the signal is weak and therefore, the quality of experimental results is limited in comparison to results obtained in transmission mode by various holographic techniques reported elsewhere.

• The Journal of Internal Korean Medicine
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• v.29 no.3
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• pp.787-799
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• 2008

Objective : Diabetic nephropathy is the most common cause of end stage renal disease. AGE, $TGF-{\beta}1$ type IV collagen, and macrophage/monocyte infiltration are the main factors of diabetic nephropathy. We investigated the effects of Salvia miltiorrhiza on renal function and histopathological changes in streptozotocin(STZ)-induced diabetic nephropathy rat model. Methods : Diabetes was induced in male Sprague-Dawley rats(290${\pm}$10g) by injecting STZ(45mg/kg) into the tail vein. Rats were divided into 3 groups(n = 6): normal, control, and salvia. After 8 weeks of administration of Salvia miltiorrhiza extract on the Salvia group, we checked 24 hrs urine, blood biochemistry and renal tissue to evaluate renal function and histopathological changes by examining parameters including albuminuria, BUN, creatinine, cholesterol, LDL, TG, macrophage/monocyte antigen(ED-1), $TGF-{\beta}1$, AGE, and type IV collagen. Results : Salvia miltiorrhiza decreased the amount of 24hrs proteinuria, and inhibited histopathological changes of diabetic nephropathy including the expression and accumulation of various factors which could promote development of diabetic nephropathy. Conclusion : These findings suggest that Salvia miltiorrhiza might protect the renal function and inhibit the development of renal injury by regulating factors including AGE, $TGF-{\beta}1$ Type IV collagen, macrophage and monocyte infiltration. So Salvia miltiorrhiza can be used for diabetic patients to prevent the progression of diabetic nephropathy.