• Korean Journal of Veterinary Research
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• v.40 no.2
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• pp.361-371
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• 2000

It has been recently reported that 2-bromopropane (2-BP) induces male reproductive toxicity in both human and experimental animals. However, delayed effects of 2-BP on male reproductive system have not been investigated in detail. The present study was conducted to investigate the testicular toxicity of 2-BP and to determine the recovery of normal spermatogenesis in Sprague-Dawley rats. Male rats aged 5 weeks were administered 1,000mg/kg 2-BP by gavage daily for 4 weeks and sacrificed sequentially at 1, 2, 3, 4 and 12 weeks after initiation of 2-BP treatment. Testicular toxicity was evaluated qualitatively by histopathological examinations and quantitatively by reproductive organ weights, spermatid head count, and repopulation index. In the 2-BP treated rats, the body weights was significantly suppressed and the weights of testes and epididymides were also decreased in a time-dependent manner. On histopathological examination, spermatogonia in stages I-VI and preleptotene and leptotene spermatocytes in stages VII-IX were strongly depleted at 1 week of dosing. Spermatogonia were depleted extensively in all spermatogenic stages at 2 weeks. Continuing with the evolution of spermatogenic cycle, zygotene spermatocytes, pachytene spermatocytes, and round spermatids were sequentially depleted at 2, 3, and 4 weeks of dosing due to the depletion of their precursor cells. Vacuolization of Sertoli cells and spermatid retention were also observed at all time points, suggesting that 2-BP induced Sertoli cell dysfunction. At 12 weeks, after 8 weeks recovery, most of the tubules appeared severely atrophic and were lined by Sertoli cells only. Leydig cell hyperplasia in the interstitial tissue was also found. In addition, dramatic reductions in the number of spermatid heads and repopulation index were observed, indicating that 2-BP-induced testicular injury is irreversible. These results indicate that 4 weeks repeated-dose of 1,000mg/kg 2-BP results in a progressive germ cell loss due to the depletion of spermatogonia followed by long-term testicular atrophy in SD rats.

• Korean Journal of Veterinary Research
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• v.41 no.3
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• pp.437-445
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• 2001

This study was performed to validate the procedure of transarterial embolization of the renal artery (TAE-RA) using iohexol-ethanol solution in dogs with unilateral experimental hydronephrosis and to evaluate the embolized kidney using B-mode ultrasonography and selective angiography. Experimental hydronephrosis was induced by ligation of unilateral ureter in 12 dogs. Ultrasonographic findings revealed that size of the kidney was significantly increased at 9 days and 17 days and the length of renal cortex was significantly decreased at 17 days after ligation of the unilateral ureter and it was in accordance with dilation of ipsilateral renal pelvis. No significant change of BUN, creatinine, ALT, calcium, and phosphorus was found immediately after unilateral experimental hydronephrosis. Therefore, it was concluded that unilateral hydronephrosis was established in 12 dogs at 17 days after ligation of ureter. Renal artery embolization was performed using selective catheterization in the hydronephrotic kidney of seven dogs and EKG, $SpO_2$, body temperature, pulse, and respiratory rate were within normal ranges during procedures. Iohexol-ethanol solution was used as embolic material. Average ethanol dose for renal artery embolization was $1.94{\pm}1.24ml/kg$. There were no dogs expired after TAE-RA and no side effects associated with regurgitation of iohexol-ethanol solution. Revascularization of renal artery was not found in angiography in dogs treated by TAE-RA at immediately after TAE-RA and 14 days after TAE-RA. Ultrasonographically, the mean longitudinal length of the embolized kidney decreased significantly at 2 and 3 months after TAE-RA compared to that of contralateral normal kidney. In summary, marked shrinkage of the embolized kidney was observed in dogs with unilateral experimental hydronephrosis treated by TAE-RA with iohexol-ethanol and no adverse effects were observed throughout the observation period. It is concluded that TAE-RA with iohexol-ethanol solution is a viable alternative to nephrectomy in dogs with unilateral hydronephrosis.

• Journal of Gastric Cancer
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• v.4 no.4
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• pp.242-251
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• 2004

Purpose: Recently, because of the increasing numbers of early gastric cancer patients and improvements in their survivals, greater attention has been directed towards the quality of life and nutritional status of gastric cancer patients after surgery. However, conventional reconstructions, Billroth- I, -II (B-I and B-II) or Roux-en-Y, have proven to have certain limitations, such as a small reservoir, and a malabsorption for iron, fat, calcium, and carotene. To overcome these limitations, we used a jejunal pouch interposition(JPI) after a distal gastrectomy not only to substitute for the small reservoir but also to maintain a physiologic pathway for ingested foods. Materials and Methods: A total of 196 gastric cancer patients who underwent a distal gastrectomy between March 2001 and February 2004 were divided into 3 groups: JPI group (n=100), B-I group (n=29), and B-II group (n=67). We assessed the patient's nutritional status, gastric emptying time, and gastrofiberscopic findings. Results: The percents of body weight loss at 6 months, 1 year, and 2 years postoperatively in the JPI group ($5.14\%,\;3.01\%,\;2.37\%$) were significantly less than those of the conventional B-I ($8.41\%,\;6.69\%,\;5.90\%$) and B-II groups ($7.50\%,\;7.65\%,\;5.86\%$) (P=0.011, 0.000, 0.013). The laboratory findings showed no significant differences between the 3 groups, except for a higher total protein level in the JPI group after 6 months postoperatively. Especially, stage I and II cancers in the JPI group showed much higher total protein levels after 1 year postoperatively. The gastric emptying times in the $\^{99m}$Tc- semisolid scans at 6 months, 1 year, and 2 years postoperatively were 102.5, 83.1, and 58.1 minutes in the JPI group, 95.5, 92.0, and 58.5 minutes in the B-I group, and 53.9, 69.1, and 50.2 minutes in the B-II group, respectively. Also, the symptomatic gastric stasis detected with a gastrofiberscope during the early postoperative period (6 months) was gradually improved. Conclusion: From a nutritional aspect, a jejunal pouch interposition after a distal gastrectomy could be an alternative reconstruction method, especially in stage I and II gastric cancer patients, in spite of the longer operation time and the probable delayed gastric emptying.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.4
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• pp.277-288
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• 2010

The multi-level $H_2O/CO_2$ profile system has been widely used to quantify the storage and advection effects on energy and mass fluxes measured by eddy covariance systems. In this study, we expanded the utility of the profile system by accommodating air sampling devices for isotope analyses of water vapor and $CO_2$. A pre-evacuated 2L glass flask was connected to the discharge of an Infrared Gas Analyzer (IRGA) of the profile system so that airs with known concentration of $H_2O$ and $CO_2$ can be sampled. To test the performance of this sampling system, we sampled airs from 8 levels (from 0.1 to 40 m) at the KoFlux tower of Gwangneung deciduous forest, Korea. Air samples in the 2L flask were separated into its component gases and pure $H_2O$ and $CO_2$ were extracted by using a vacuum extraction line. This novel technique successfully produced vertical profiles of ${\delta}D$ of $H_2O$ and ${\delta}^{13}C$ of $CO_2$ in a mature forest, and estimated ${\delta}D$ of evapotranspiration (${\delta}D_{ET}$) and ${\delta}^{13}C$ of $CO_2$ from ecosystem respiration (${\delta}^{13}C_{resp}$) by using Keeling plots. While technical improvement is still required in various aspects, our sampling system has two major advantages over other proposed techniques. First, it is cost effective since our system uses the existing structure of the profile system. Second, both $CO_2$ and $H_2O$ can be sampled simultaneously so that net ecosystem exchange of $H_2O$ and $CO_2$ can be partitioned at the same temporal resolution, which will improve our understanding of the coupling between water and carbon cycles in terrestrial ecosystems.

• Journal of Wetlands Research
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• v.24 no.3
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• pp.204-212
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• 2022

The LID technique began to be applied in Korea after 2009, and LID facilities are installed and operated for rainwater management in business districts such as the Ministry of Environment, the Ministry of Land, Infrastructure and Transport, and LH Corporation, public institutions, commercial land, housing, parks, and schools. However, looking at domestic cases, the application cases and operation periods are insufficient compared to those outside the country, so appropriate design standards and measures for operation and maintenance are insufficient. In particular, LID facilities constructed using LID techniques need to maintain the environment inside LID facilities because hydrological and environmental effects are expressed by material circulation and energy flow. The LID facility is designed with the treatment capacity planned for the water circulation target, and the proper maintenance, vegetation, and soil conditions are periodically identified, and the efficiency is maintained as much as possible. In other words, the soil created in LID is a very important design element because LID facilities are expected to have effects such as water pollution reduction, flood reduction, water resource acquisition, and temperature reduction while increasing water storage and penetration capacity through water circulation construction. In order to maintain and manage the functions of LID facilities accurately, the current state of the facilities and the cycle of replacement and maintenance should be accurately known through various quantitative data such as soil contamination, snow removal effects, and vegetation criteria. This study was conducted to investigate the current status of LID facilities installed in Korea from 2009 to 2020, and analyze soil changes through the continuity and current status of LID facilities applied over the past 10 years after collecting soil samples from the soil layer. Through analysis of Saturn, organic matter, hardness, water contents, pH, electrical conductivity, and salt, some vegetation-type LID facilities more than 5 to 7 years after construction showed results corresponding to the lower grade of landscape design. Facilities below the lower level can be recognized as a point of time when maintenance is necessary in a state that may cause problems in soil permeability and vegetation growth. Accordingly, it was found that LID facilities should be managed through soil replacement and replacement.