• Journal of Sensor Science and Technology
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• v.31 no.2
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• pp.115-119
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• 2022

A readout circuit for a mercury-cadmium-telluride (MCT)-amplified mid-wave infrared (IR) photodetector was realized and applied to noncontact chemical agent detectors based on a quantum cascade laser (QCL). The QCL emitted 250 times for each wavelength in 0.2-㎛ steps from 8 to 12 ㎛ with a frequency of 100 kHz and duty ratio of 10%. Because of the nonconstant QCL emission power during on-duty, averaging the photodetector signals is essential. Averaging can be performed in digital back-end processing through a high-speed analog-to-digital converter (ADC) or in analog front-end processing through an integrator circuit. In addition, it should be considered that the 250 IR data points should be completely transferred to a PC during each wavelength tuning period of the QCL. To average and minimize the IR data, we designed a readout circuit using the analog front-end processing method. The proposed readout circuit consisted of a switched-capacitor integrator, voltage level shifter, relatively low-speed analog-to-digital converter, and micro-control unit. We confirmed that the MCT photodetector signal according to the QCL source can be accurately read and transferred to the PC without omissions.

• Anatomy and Cell Biology
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• v.56 no.4
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• pp.421-427
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• 2023

Bladder exstrophy is a rare congenital condition of the pelvis, bladder, and lower abdomen that opens the bladder against the abdominal wall, produces aberrant growth, short penis, upward curvature during erection, wide penis, and undescended testes. Exstrophy affects 1/30,000 newborns. The bladder opens against the abdominal wall in bladder exstrophy, a rare genitourinary condition. This study is vital to provide appropriate therapy choices as a basis to improve patient outcomes. This study may explain bladder exstrophy and provide treatment. Epispadias, secretory placenta, cloacal exstrophy, and other embryonic abnormalities comprise the exstrophy-spades complex. The mesenchymal layer does not migrate from the ectoderm and endoderm layers in the first trimester, affecting the cloacal membrane. Embryological problems define the exstrophy-aspidistra complex, which resembles epimedium, classic bladder, cloacal exstrophy, and other diseases. Urogenital ventral body wall anomalies expose the bladder mucosa, causing bladder exstrophy. Genetic mutations in the Hedgehog cascade pathway, Wnt signal, FGF, BMP4, Alx4, Gli3, and ISL1 cause ventral body wall closure and urinary bladder failure. External factors such as high maternal age, smoking moms, and high maternal body mass index have also been associated to bladder exstrophy. Valproic acid increases bladder exstrophy risk; chemicals and pollutants during pregnancy may increase bladder exstrophy risk. Bladder exstrophy has no identified cause despite these risk factors. Exstrophy reconstruction seals the bladder, improves bowel function, reconstructs the vaginal region, and restores urination.

• Journal of Microbiology and Biotechnology
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• v.34 no.3
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• pp.681-688
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• 2024

The accurate and rapid detection of methicillin-resistance of Staphylococcus aureus (SA) holds significant clinical importance. However, the methicillin-resistance detection strategies commonly require complicated cell lysis and gene extraction. Herein, we devised a novel colorimetric approach for the sensitive and accurate identification of methicillin-resistance of SA by combining allosteric probe-based target recognition with self-primer elongation-based target recycling. The PBP2a aptamer in the allosteric probe successfully identified the target MRSA, leading to the initiation of self-primer elongation based-cascade signal amplification. The peroxidase-like hemin/G-quadruplex undergo an isothermal autonomous process that effectively catalyzes the oxidation of ABTS2- and produces a distinct blue color, enabling the visual identification of MRSA at low concentrations. The method offers a shorter duration for bacteria cultivation compared to traditional susceptibility testing methods, as well as simplified manual procedures for gene analysis. The overall amplification time for this test is 60 min, and it has a detection limit of 3 CFU/ml. In addition, the approach has exceptional selectivity and reproducibility, demonstrating commendable performance when tested with real samples. Due to its advantages, this colorimetric assay exhibits considerable potential for integration into a sensor kit, thereby offering a viable and convenient alternative for the prompt and on-site detection of MRSA in patients with skin and soft tissue infections.

• Nutritional Sciences
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• v.7 no.1
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• pp.23-30
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• 2004

As a central component of a novel protein kinase cascade, the activation of the mitogen-activated protein (MAP) kinase cascade has attracted considerable attention. We sought to determine the effect of exercise and diet on the activation of the extracellular-signal regulated protein kinase (ERK) 1/2 and the p38 MAP kinase pathways in rat soleus muscle. Forty-eight Sprague-Dawley rats were assigned to one of two dietary conditions: high-carbohydrate (CHO) or high-fat (FAT). Animals having each dietary condition were further divided into one of three subgroups: a sedentary control group that did not exercise (NT), a group that performed 8 weeks of treadmill running and was sacrificed 48 h after their final treadmill run (CE), and a group that was sacrificed immediately after their final routine exercise training (AE). A high-fat diet did not have any significant effect on phosphorylated and total forms of ERK 1/2 or p38 MAP kinase. In chronically trained muscle that was taken 48 h after the last training, phosphorylated ERK 1/2 significantly increased only in the FAT but not in the CHO groups. In the case of total ERK 1/2, it increased significantly for both groups. In contrast, both phosphorylated and total forms of p38 MAP kinase decreased markedly compared to sedentary muscle. In muscle that was taken immediately after a last bout of exercise, phosphorylated ERK 1/2 increased in both groups but statistical significance was seen only in the CHO group. Total ERK 1/2 in acutely stimulated muscle increased only in the CHO-AE group even though the degree was much lower than the phosphorylated status. Muscle that was taken immediately after the routine training increased in phosphorylation status of p38 MAP kinase for both dietary conditions. However, statistical significance was seen only in the CHO group owing to a large variation with FAT. In conclusion, a high-fat diet per se did not have any notable effect versus a high-carbohydrate diet on MAP kinase pathways. However, when diet (either CHO or FAT) was combined with exercise and/or training, there was differentiated protein expression in MAP kinase pathways. This indicates MAP kinase pathways have diverse control mechanisms in slow-twitch fibers.

• Development and Reproduction
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• v.18 no.4
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• pp.197-212
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• 2014

Osteosarcoma (OS) is one of the most common malignant primary bone tumors and NF-${\kappa}B$ appears to play a causative role, but the mechanisms are poorly understood. OS is one of the pleomorphic, highly metastasized and invasive neoplasm which is capable to generate osteoid, osteoclast and osteoblast matrix. Its high incidence has been reported in adolescent and children. Cell signal cascade is the pivotal functional mechanism acquired during the differentiation, proliferation, growth and survival of the cells in neoplasm including OS. The major limitation to the success of chemotherapy in OS is the development of multidrug resistance (MDR). Answers to all such queries might come from the knock-in experiments in which the combined approach of miRNAs with NF-${\kappa}B$ pathway is put into use. Abnormal miRNAs can modulate several epigenetical switching as a hallmark of number of diseases via different cell signaling. Studies on miRNAs have opened up the new avenues for both the diagnosis and treatment of cancers including OS. Collectively, through the present study an attempt has been made to establish a new systematic approach for the investigation of microRNAs, bio-physiological factors and their target pairs with NF-${\kappa}B$ to ameliorate oncogenesis with the "bridge between miRNAs and NF-${\kappa}B$". The application of NF-${\kappa}B$ inhibitors in combination with miRNAs is expected to result in a more efficient killing of the cancer stem cells and a slower or less likely recurrence of cancer.

• Clinical and Experimental Reproductive Medicine
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• v.33 no.2
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• pp.115-123
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• 2006

Objective: To investigate new signal transduction cascade through integrin, FAK and ERK in the suppressed cell proliferation by GnRH-I and -II. Method: Human endometrial cancer cells (HEC1A) were cultured under the following condition: DMEM/F12 (10% FBS). GnRH-I and -II were treated time (0, 5, 10, 15, 20, 30 min; 100 nM) and dose (10 nM or 100 nM; 20 min) dependent manner according to experimental purposes. Cell proliferation was measured using [$^3H$] thymidine incorporation assay. Immunoblotting was utilized to detect proteins. Results: GnRH-I and -II inhibited proliferation of HEC1A cells and induced expression of integrin ${\beta}3$. Phosphorylation of FAK and ERK were induced by GnRH-I and -II. Conclusion: GnRH inhibited cell proliferation via the expression of integrin and FAK, ERK phosphorylation.

• Korean Journal of Food Science and Technology
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• v.50 no.3
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• pp.349-355
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• 2018

Ginsenoside Rg5, one of the protopanaxadiol ginsenosides of wood-cultivated ginseng, has been implicated in various diseases, such as diabetes, cancer, and hypertension; however, its angiogenic activity and molecular mechanisms have not yet been elucidated. Here, we found that wood-cultivated ginseng extract and ginsenoside Rg5 increase in vitro proliferation, migration, and tube-like structure formation, which are typical phenomena associated with angiogenesis, in cultured human umbilical vein endothelial cells (HUVECs). Moreover, Ginsenoside Rg5 stimulated the phosphorylation of Akt, endothelial nitric oxide (NO) synthase (eNOS), and extracellular-regulated kinase (ERK)1/2, which are well-known signal mediators of the angiogenic pathway. Furthermore, Ginsenoside Rg5 did not accelerate the activation of ICAM-1 and VCAM-1 which are inflammatory response mediators. These results suggest that wood-cultivated ginseng extract and ginsenoside Rg5 stimulated in vitro angiogenesis by activating the Akt/eNOS- and ERK1/2-dependent signal pathways without inducing vascular inflammation.

• Journal of Photoscience
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• v.9 no.2
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• pp.229-232
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• 2002

There are two distinct UV-responsive signaling pathways in UV-irradiated mammalian cells, i.e., the DNA damage-dependent and -independent pathways. The former occurs in nucleus and results in growth arrest and apoptosis via post-translational modification of p53. The latter is initiated by oxidative stress and/or by damages in cell membrane or cytoplasm, which activate signaling cascade through intracellular molecules including mitogen activated protein kinases (MAPK). In normal human fibroblastic cells, all of MAPK family members, extracellular signal-related kinases (ERK), c-Jun N-terminal kinases (JNK) and p38, were rapidly phosphorylated following UV-irradiation. ERK phosphorylation was suppressed by an inhibitor of receptor tyrosine kinases (RTK). As ERK usually responds to mitogenic stimuli from RTK ligands, UV-induced ERK phosphorylation may be linked to the proliferation of survived cells. In contrast, phosphorylation of JNK and p38, as well as apoptosis, were modulated by the level of UV-generated oxidative stress Therefore, JNK and p38 may take part in oxidative stress-mediated apoptosis. Phosphorylation of p53 at Ser and Thr residues are essential for stabilization and activation of p53. Among several sites reported, we confirmed phosphorylation at Ser-15 and Ser-392 after UV-irradiation. Both of these were inhibited by a phosphoinositide 3-kinase inhibitor, presumably due to the shutdown of signals from DNA damage to p53. Phosphorylation at Ser-392 was also sensitive to an antioxidant and a p38 inhibitor, suggesting that Ser-392 of p53 is one of the possible points where DNA damage-dependent and -independent apoptic signals merge. Thus, MAPK pathway links UV-induced intracellular signals to the nuclear responses and modifies DNA damage-dependent cellular outcome, resulting in the determination of cell death.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.1
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• pp.52-58
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• 2009

A low voltage, low power delta-sigma modulator is proposed for cardiac pacemaker applications. A cascade of delta-sigma modulator stages that employ a feedforward topology has been used to implement a high-resolution oversampling ADC under the low supply. An inverter-based switched-capacitor circuit technique is used for low-voltage operation and ultra-low power consumption. An experimental prototype of the proposed circuit has been implemented in a $0.35-{\mu}m$ CMOS process, and it achieves 61-dB SNDR, 63-dB SNR, and 65-dB DR for a 120-Hz signal bandwidth at 7.6-kHz sampling frequency. The power consumption is only 280 nW at 1-V power supply.

• Journal of Microbiology and Biotechnology
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• v.16 no.7
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• pp.1078-1083
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• 2006

Capsaicin is the active ingredient in chili pepper and has an inhibitory effect on Helicobacter pylori growth and $NF-{\kappa}B$ activation. The present study examined the effect of capsaicin on interleukin (IL)-8 production by H. pylori ATCC 43504-infected MKN-45 cells, a gastric epithelial cell line. The viability of the MKN-45 cells treated with capsaicin at 0, 50, 100, 250, and $500\;{\mu}M$ was 99, 98, 99, 99, and 85%, respectively. A capsaicin concentration as low as $50\;{\mu}M$ significantly inhibited the IL-8 production induced by H. pylori ATCC 43504 infection (43.2% of control) during 24 h of incubation. However, low concentrations of capsaicin $(50\;and\;100{\mu}M)$ did not significantly inhibit the IL-8 production by $TNF-{\alpha}-$ or PMA-treated MKN-45 cells. Therefore, the overall inhibitory effect of capsaicin on H. pylori ATCC 43504 was the sum of H. pylori ATCC 43504 growth inhibition, host cell survival, and $NF-{\kappa}B$ signal cascade inhibition.