• Applied Chemistry for Engineering
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• v.32 no.4
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• pp.461-466
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• 2021

In this article, a portable and cost-effective voltammetric biosensor with nanoparticles was developed for the measurements of heterogeneous nuclear ribonucleoprotein A1 protein (hnRNP A1) biomarker which can potentially be used for lung cancer diagnosis. Gold nanoparticles were first electrodeposited onto screen printed carbon electrode (SPCE) followed by immobilizing a single stranded DNA aptamer specific to hnRNP A1 onto the electrode surface. Ethanolamine was also used when immobilizing DNA aptamer on the surface to prevent signals from non-specific adsorption events. Sequential injection of hnRNP A1 biomarker and anti-hnRNP A1 conjugated with alkaline phosphatase (ALP) onto the aptamer chip surface allows to form the sandwich complex of DNA aptamer/hnRNP A1/ALP-anti-hnRNP A1 on the electrode surface which further reacted with 4-aminophenyl phosphate (APP). The electrocatalytic reaction of the enzyme, ALP, and the substrate, APP, resulting in the oxidative current response changes at -0.05 and -0.17 V (vs. Ag/AgCl) against the hnRNP A1 concentration was measured using cyclic and differential pulse voltammetry, respectively. The Au nanoparticles-integrated voltammetric biosensor was applied to analyze human normal serum solutions possibly suggesting potential applicability for lung cancer diagnosis.

• The Korean Journal of Nuclear Medicine
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• v.32 no.6
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• pp.482-489
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• 1998

Purpose: Radionuclide cisternography may be helpful in understanding pathophysiology of postural head-ache and low CSF pressure in patients with spontaneous intracranial hypotension. The purpose of this study was to characterize radionuclide cisternographic findings of spontaneous intracranial hypotension. Materials and Methods: The study population consists of 15 patients with spontaneous intracranial hypotension. Diagnosis was based on their clinical symptoms and results of lumbar puncture. All patients underwent radionuclide cisternography following injection of 111 to 222 MBq of Tc-99m DTPA into the lumbar subarachnoid space. Sequential images were obtained between 112 hour and 24 hour after the injection of Tc-99m DTPA. Radioactivity of the bladder, soft tissue uptake, migration of radionuclide in the subarachnoid space, and extradural leakage of radionuclide were evaluated according to the scan time. Results: Radionuclide cisternogram showed delayed migration of radionuclide into the cerebral convexity (14/15), increased soft tissue uptake (11/15), and early visualization of bladder activity at 30min (6/10) and 2hr (13/13). Cisternography also demonstrated leakage site of CSF in 4 cases and 2 of these were depicted at 30min. Epidural blood patch was done in 11 patients and headache was improved in all cases. Conclusion: The characteristic findings of spontaneous intracranial hypotension were delayed migration of radionuclide and early visualization of the soft tissue and bladder activity. These scintigraphic findings suggest that CSF leakage rather than increased CSF absorption or decreased production may be the main pathophysiology of spontaneous intracranial hypotension. Early and multiple imaging including the bladder and soft tissue is required to observe the entire dynamics of radionuclide migration.

• The Korean Journal of Nuclear Medicine
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• v.33 no.3
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• pp.247-261
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• 1999

Purpose: The aim of this study was to evaluate the normal values of regional cerebral blood flow (rCBF) and cerebrovascular reserve (CVR) in normal children to aged volunteers using Tc-99m HMPAO, Materials and Methods: Thirty four right-handed normal volunteers (20 males, 14 females, mean age $40.3{\pm}24.9$ years, range 4 to 82 years) were underwent rost/acetazolamide (ACZ) brain SPECT using Tc-99m HMPAO and the sequential injection and subtraction method. rCBF was estimated on the basis of a semiquantitative approach by means of right/left ratio, region/cerebellum and region to whole brain ratios in (rental, parietal, temporal, and occipital lobes, basal ganglia, thalami, and cerebellum. CVR was measured by means of % perfusion increase calculated as % mean count change compared to rest rCBF in each regions. Results: Mean values of right to left ratios range from 1.004 to 1.018, rCBF was highest in cerebellum and lowest in basal ganglia and thalami. Frontal and temporal rCBF decreased while occipital and thalamic rCBF increased according to age. No sexual difference of rCBF was noted. Mean CVR was $29.9{\pm}12.9%$. Mean CVR significantly increased to late teens, and declined thereafter. After 6th decade, CVR in both frontal lobes, left parietal lobe and right basal ganglia decreased significantly with advancing age. There was no sexual difference of CVR. Conclusion: Quantitative assessment of CVR was possible by ACZ Tc-99m HMPAO brain SPECT. It revealed that rCBF and CVR changed according to age in normal Korean volunteers. There was no sexual difference.

• Clinical and Experimental Reproductive Medicine
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• v.21 no.2
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• pp.165-176
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• 1994

This study was carried out to investigate the effect of the timing and dose of human chorionic gonadotropin(hCG) on oocyte recovery, in vitro fertilization, and preimplantation development in superovulation of mouse. F1 hybrid($C57BL{\times}CBA$) mice were obtained and superovulation was induced in female mice by sequential intraperitoneal injection of PMSG and hCG. In the first series of experiments, mice received 5 IU of PMSG given intraperitoneally, and 48 hours later were injected 1 IU, 5 IU, or 10 IU of hCG respectively. In the second series of experiments, mice received 5 IU of PMSG given intraperitoneally and were injected 5IU of hCG 36, 48, or 60 hours later respectively. 1. When the mice received 5 IU of PMSG given intraperitoneally and 48 hours later were injected 1 ItT, 5 IU, or 10 IU of hCG respectively, there were no differences in the total number of the oocytes obtained from the three experimental groups. When the cultures were examined 48 hrs after the termination of insemination the proportion of unfragmented oocytes which had developed over two-cell stage was observer to be lowest in 10 IU hCG group. When the cultrues were examined 120 hour after termination of insemination the proportion of embryos which had developed to the blastocyst stage was observed to be significantly higher in 10IU hCG group than 5IU hCG group(p<0.05), but there was no difference between 10 IU hCG group and 1IU hCG group. 2. When the mice received 5 IU of PMSG and were injected 5 IU of hCG 36, 48, or 60 hours later respectively, there were no differences in the total number of oocytes obtained from the three experimental groups. When cultures were examined 48 hour after the termination of insemination the proportion of unfragmented oocytes which had developed over two-cell stage was observed to be significantly lower in 36 hour interval group than 48 hour interval and 60 hour interval group(p<0.05). When the cultures were examined 120 hour after termination of insemination the proportion of embryos which had developed to the blastocyst stage was found to be higher in 60 hour interval group than 36 interval or 48 hour interval group (P<0.05), and the proportion of hatching blastocyst was found to be higher in 60 hour interval group as well. In this study, it was concluded that the administration of adequate dose of hCG, and long (60 hour) PMSG-hCG interval were necessary in superovulation of mice($C57BL{\times}CBA$) in order to get a large number of oocytes which had an early oocytes which had an early embryonic developmental capability when fertilized in vitro, and especially it had better have been avoided to administer a large dose of hCG.

• The Korean Journal of Nuclear Medicine
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• v.29 no.1
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• pp.79-83
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• 1995

Purpose : We analysed $^{99m}Tc-MAG_3$ renal scans to evaluate renal function of transplanted kidney and to detect various renal transplant complications, measuring the ratio of renal radioactivity at three minutes to that at 20 minutes(elimination index). Material and Methods : The fifty seven renal transplantation recipients were studied. There were 50 normal functioning transplanted kidneys as group I and 7 abnormal function-ing transplanted kidney, including 5 cases of acute renal rejection, 2 cases of acute tubular necrosis as group IIl. The protocol consisted of: (1) $^{99m}Tc-MAG_3$ 740MBq injection intravenously : (2) sequential imaging for 2min(60two-second images) followed by 30min(30 sixty-second images) : (3) drawing of region of interest(ROI) on renal imaging; (4) time-activity corves were generated from renal ROI after background subtraction, and time of maximum activity($T_{max}$) and half time of maximal peak radioactivity($T_{1/2}$) were produced in the renogram curve. (5) EI through Bischof-Delaloye method as determined on the renogram curve. Results : Normal group( I ) shows mean EI of 2.21(95.0% Confidence limit of 2.01-2.87), $T_{max}$ of 154 sec, $T_{1/2}$ of 1,139 sec. Abnormal group(II) shows mean EI of 0.74, $T_{max}$ of 1,466 sec, $T_{1/2}$ of 19,224 sec. The EI, $T_{max}$, $T_{1/2}$, BUN and serum creatinine values are significantly different between normal group(I) and abnormal group(II) (p<0.0001). Conclusion : By measuring EI with $^{99m}Tc-MAG_3$, renal function of transplanted kidney could be easily evaluated and various complications could be detected early.

• Progress in Medical Physics
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• v.23 no.4
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• pp.309-316
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• 2012

Multimodal-imaging technique has been rapidly developed for improvement of diagnosis and evaluation of therapeutic effects. In despite of integrated hardware, registration accuracy was decreased due to a discrepancy between multimodal image and insufficiency of count in accordance with different acquisition method of each modality. The purpose of this study was to improve the PET image by event data resampling through analysis of data format, noise and statistical properties of small animal PET list data. Inveon PET listmode data was acquired as static data for 10 min after 60 min of 37 MBq/0.1 ml $^{18}F$-FDG injection via tail vein. Listmode data format was consist of packet containing 48 bit in which divided 8 bit header and 40 bit payload space. Realigned sinogram was generated from resampled event data of original listmode by using adjustment of LOR location, simple event magnification and nonparametric bootstrap. Sinogram was reconstructed for imaging using OSEM 2D algorithm with 16 subset and 4 iterations. Prompt coincidence was 13,940,707 count measured from PET data header and 13,936,687 count measured from analysis of list-event data. In simple event magnification of PET data, maximum was improved from 1.336 to 1.743, but noise was also increased. Resampling efficiency of PET data was assessed from de-noised and improved image by shift operation of payload value of sequential packet. Bootstrap resampling technique provides the PET image which noise and statistical properties was improved. List-event data resampling method would be aid to improve registration accuracy and early diagnosis efficiency.