• The Korean Journal of Physiology and Pharmacology
• /
• 제7권2호
• /
• pp.53-57
• /
• 2003

The glutamate receptors (GluRs) are key receptors for modulatory synaptic events in the central nervous system. It has been reported that glutamate increases the intracellular $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) and induces cytotoxicity. In the present study, we investigated whether the glutamate-induced $[Ca^{2+}]_i$ increase was associated with the activation of ionotropic (iGluR) and metabotropic GluRs (mGluR) in substantia gelatinosa neurons, using spinal cord slice of juvenile rats (10${\sim}21 day). $[Ca^{2+}]_i$ was measured using conventional imaging techniques, which was combined with whole-cell patch clamp recording by incorporating fura-2 in the patch pipette. At physiological concentration of extracellular $Ca^{2+}$, the inward current and $[Ca^{2+}]_i$ increase were induced by membrane depolarization and application of glutamate. Dose-response relationship with glutamate was observed in both $Ca^{2+}$ signal and inward current. The glutamate-induced $[Ca^{2+}]_i$ increase at holding potential of -70 mV was blocked by CNQX, an AMPA receptor blocker, but not by AP-5, a NMDA receptor blocker. The glutamate-induced $[Ca^{2+}]_i$ increase in $Ca^{2+}$ free condition was not affected by iGluR blockers. A selective mGluR (group I) agonist, RS-3,5-dihydroxyphenylglycine (DHPG), induced $[Ca^{2+}]_i$ increase at holding potential of -70 mV in SG neurons. These findings suggest that the glutamate-induced $[Ca^{2+}]_i$ increase is associated with AMPA-sensitive iGluR and group I mGluR in SG neurons of rats.

• 대한방사선기술학회지:방사선기술과학
• /
• 제12권1호
• /
• pp.3-16
• /
• 1989

In order to investigate the in vivo effect of $^{60}Co$ radiation on rabbit liver, the uptake ratio and regional excretory value in hepatocytes and Kupffer cells were estimated during acute and chronic hepatic injuries. The left lobe of liver was irradiated at 15 Gy or 30 Gy with a single dose and subsequent changes were analysed with a seial nuclear medicine imaging by using $^{99m}Tc-phytate,\;^{99m}Tc-DISIDA\;and\;^{99m}Tc-HSA$ and resulting data were computerized. The degree of hepatic damage, duration of the injury, and recovery pattern after the irradation were in agreement with the findings of other investigations. However, out values were more quantitative evacuation than those of other publications. Recovery of decreased uptake of $^{99m}Tc-phytate$ was delayed approximately $2{\sim}3$ days later than that of $^{99m}Tc-DISIDA$. In acute radiation induced injury, the results demonstrated that the recovery of Kupffer cells was delayed more than that of hepatocytes. This discrepancy was considered due to the differences in repair activities between these cell types. The decreased of regional excretory value in irradiated area was found to be dose-dependent but had no corelation with regional uptakes of DISIDA and phytate. The decreased of regional excretory value observed in non-irradiated region suggested that irradiated liver might induce an indirect effect.

• Asian Pacific Journal of Cancer Prevention
• /
• 제14권1호
• /
• pp.63-68
• /
• 2013

Background: Tumor angiogenesis correlates with recurrence and appears to be a prognostic factor for both breast and prostate cancers. In the present study, we aimed to investigate the correlation of microvessel density (MVD), a measure of angiogenesis, with nuclear pleomorphism, mitotic count, and vascular invasion in breast and prostate cancers at preclinical and clinical levels. Methods: Samples from xenograft tumors of luminal B breast cancer and prostate adenocarcinoma, established by BT-474 and PC-3 cell lines, respectively, and commensurate human paraffin-embedded blocks were obtained. To determine MVD, specimens were immunostained for CD-34. Nuclear pleomorphism, mitotic count, and vascular invasion were determined using hematoxylin and eosin (H&E)-stained slides. Results: MVD showed significant correlations with nuclear pleomorphism (r=0.68, P=0.03) and vascular invasion (r=0.77, P=0.009) in breast cancer. In prostate cancer, MVD was significantly correlated with nuclear pleomorphism (r=0.75, P=0.013) and mitotic count (r=0.75, P=0.012). In the breast cancer xenograft model, a significant correlation was observed between MVD and vascular invasion (r=0.87, P=0.011). In the prostate cancer xenograft model, MVD was significantly correlated with all three parameters (nuclear pleomorphism, r=0.95, P=0.001; mitotic count, r=0.91, P=0.001; and vascular invasion, r=0.79, P=0.017; respectively). Conclusions: Our results demonstrate that MVD is correlated with nuclear pleomorphism, mitotic count, and vascular invasion at both preclinical and clinical levels. This study therefore supports the predictive value of MVD in breast and prostate cancers.

• IMMUNE NETWORK
• /
• 제12권6호
• /
• pp.284-290
• /
• 2012

Innate immune cells sense and respond to the cytoplasmic infection of bacterial pathogens through NLRP3, NLRC4 or AIM2 inflammasome depending on the unique molecular pattern of invading pathogens. The infection of flagellin- or type III secretion system (T3SS)-containing Gram-negative bacteria such as Salmonella enterica serovar Typhimurium (S. typhimurium) or Pseudomonas aeruginosa (P. aeruginosa) triggers NLRC4-dependent caspase-1 activation leading to the secretion of proinflammatory cytokines such as interleukin-1-beta (IL-$1{\beta}$) and IL-18. Previous studies have shown that apoptosis-associated speck-like protein containing a CARD (ASC) is also required for Salmonella-induced caspase-1 activation, but it is still unclear how ASC contributes to the activation of NLRC4 inflammasome in response to S. typhimurium infection. In this study, we demonstrate that S. typhimurium triggers the formation of ASC oligomer in a potassium depletion-independent manner as determined by in vitro crosslinking and in situ fluorescence imaging. Remarkably, inhibition of potassium efflux failed to block Salmonella-promoted caspase-1 activation and macrophage cell death. These results collectively suggest that ASC is substantially oligomerized to facilitate the activation of caspase-1 in response to S. typhimurium infection. Contrary to NLRP3 inflammasome, intracellular potassium depletion is not critical for NLRC4 inflammasome signaling by S. typhimurium.

• 천문학회보
• /
• 제35권1호
• /
• pp.41.1-41.1
• /
• 2010

IGRINS (the Immersion GRating Infrared Spectrograph) is a high resolution infrared spectrograph which is being developed by a collaboration of the University of Texas, the Korea Astronomy and Space Science Institute, and Kyung Hee University. The wavelength calibration unit of IGRINS will be situated between the telescope flange and IGRINS dewar. It will include Th-Ar hallow cathode lamp, optical elements, and gas absorption cell for the case that requires precise calibration (e.g., radial velocity observation). The system will also use a tungsten halogen lamp in an integrating sphere as a blackbody source for the flat-field imaging. IGRINS will be placed initially on the McDonald 2.7m Harlan J. Smith telescope and later on 4-8m class telescopes. We present an overview of the plan for the wavelength calibration sources and of the development process for the optical and mechanical design of the IGRINS calibration system.

• Journal of Yeungnam Medical Science
• /
• 제31권1호
• /
• pp.43-47
• /
• 2014

Extramedullary plasmacytoma (EMP) is a rare disease that occurs in 3% to 5% of patients with plasma cell disorder. It occurs most commonly in the upper respiratory tract and the oral cavity. Very few EMP cases have been reported in the central nervous system (CNS). We report herein an unusual case of EMP in the nasal cavity that recurred in the CNS without systemic involvement. A 67-year-old man visited our hospital due to a month-long bout with exophthalmos. He was diagnosed with EMP in the nasal cavity, paranasal sinus, and orbital cavity. He received radiotherapy to which he had complete responses. After 2 years, he visited our hospital because of a month-long headache. He was diagnosed with EMP recurrence in the CNS via brain magnetic resonance imaging and cerebrospinal fluid analysis. He was treated with whole brain radiotherapy and intrathecal chemotherapy with methotrexate, but he expired due to pneumonia.

• The Korean Journal of Physiology and Pharmacology
• /
• 제12권6호
• /
• pp.315-321
• /
• 2008

Eugenol is widely used in dentistry to relieve pain. We have recently demonstrated voltage-gated $Na^+$ and $Ca^{2+}$ channels as molecular targets for its analgesic effects, and hypothesized that eugenol acts on $P2X_3$, another pain receptor expressed in trigeminal ganglion (TG), and tested the effects of eugenol by whole-cell patch clamp and $Ca^{2+}$ imaging techniques. In the present study, we investigated whether eugenol would modulate 5'-triphosphate (ATP)-induced currents in rat TG neurons and $P2X_3$-expressing human embryonic kidney (HEK) 293 cells. ATP-induced currents in TG neurons exhibited electrophysiological properties similar to those in HEK293 cells, and both ATP- and $\alpha$, $\beta$-meATP-induced currents in TG neurons were effectively blocked by TNP-ATP, suggesting that $P2X_3$ mediates the majority of ATP-induced currents in TG neurons. Eugenol inhibited ATP-induced currents in both capsaicin-sensitive and capsaicin-insensitive TG neurons with similar extent, and most ATP-responsive neurons were IB4-positive. Eugenol inhibited not only $Ca^{2+}$ transients evoked by $\alpha$, $\beta$-meATP, the selective $P2X_3$ agonist, in capsaicin-insensitive TG neurons, but also ATP-induced currents in $P2X_3$-expressing HEK293 cells without co-expression of transient receptor potential vanilloid 1 (TRPV1). We suggest, therefore, that eugenol inhibits $P2X_3$ currents in a TRPV1-independent manner, which contributes to its analgesic effect.

• The Plant Pathology Journal
• /
• 제32권4호
• /
• pp.300-310
• /
• 2016

Pathogen infection in plants induces complex responses ranging from gene expression to metabolic processes in infected plants. In spite of many studies on biotic stress-related changes in host plants, little is known about the metabolic and phenotypic responses of the host plants to Pseudomonas cichorii infection based on image-based analysis. To investigate alterations in tomato plants according to disease severity, we inoculated plants with different cell densities of P. cichorii using dipping and syringe infiltration methods. High-dose inocula (${\geq}10^6cfu/ml$) induced evident necrotic lesions within one day that corresponded to bacterial growth in the infected tissues. Among the chlorophyll fluorescence parameters analyzed, changes in quantum yield of PSII (${\Phi}PSII$) and non-photochemical quenching (NPQ) preceded the appearance of visible symptoms, but maximum quantum efficiency of PSII ($F_v/F_m$) was altered well after symptom development. Visible/near infrared and chlorophyll fluorescence hyperspectral images detected changes before symptom appearance at low-density inoculation. The results of this study indicate that the P. cichorii infection severity can be detected by chlorophyll fluorescence assay and hyperspectral images prior to the onset of visible symptoms, indicating the feasibility of early detection of diseases. However, to detect disease development by hyperspectral imaging, more detailed protocols and analyses are necessary. Taken together, change in chlorophyll fluorescence is a good parameter for early detection of P. cichorii infection in tomato plants. In addition, image-based visualization of infection severity before visual damage appearance will contribute to effective management of plant diseases.

• 대한세포병리학회지
• /
• 제5권2호
• /
• pp.90-98
• /
• 1994

There has been a marked increase in the utility of aspiration cytology for pathologic diagnosis. It may be applied to any kinds of organs and substitutes surgical biopsy. Be cause of the high risk of complication and difficulties In localization, aspiration cytology in the central nervous system (CNS) has been used with less frequency compared to other sites. However, with the advent of sophisticated imaging instruments, aspiration cytology of lesions in the CNS is being used increasingly. We present cytologic features of brain tumors as well as corresponding histologic findings. Eight types of tumors were aspirated intraoperatively and stained with the Papanicolaou method; 1 anaplastic astrocytoma, 1 glioblastoma multiforme, 1 ependymoma, 1 malignant ependymoma, 1 central neurocytoma, 1 primitive neuroectodermal tumor, 1 benign neurogenic tumor and 1 germinoma. Cytologic features of the CNS neoplasms were quite similar to those of histology except one spindle cell tumor. Reviewing various CNS neoplasms, it appears that cytology may be a useful diagnostic method.

• Applied Microscopy
• /
• 제42권2호
• /
• pp.111-114
• /
• 2012

The scanning electron microscopy is an ideal technique for examining plant surface at high resolution. Most hydrate samples, however, must be fix and dehydrate for observation in the scanning electron microscope. Because the microscopes operate under high vacuum, most specimens, especially biological samples, cannot withstand water removal by the vacuum system without morphological distortion. Cryo-techniques can observe in their original morphology and structure without various artifacts from conventional sample preparation. Rapid cooling is the method of choice for preparing plant samples for scanning electron microscopy in a defined physiological state. As one of cryo-technique, high-pressure freezing allows for fixation of native non-pretreated samples up to $200{\mu}M$ thick and 2 mm wide with minimal or no ice crystal damage for the freezing procedure. In this study, we could design to optimize structural preservation and imaging by comparing cryo-SEM and convention SEM preparation, and observe a fine, well preserved Arabidopsis stem's inner ultrastructure using HPF and cryo-SEM. These results would suggest a useful method of cryo-preparation and cryo-SEM for plant tissues, especially intratubule and vacuole rich structure.