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Hyeon Hoe Kim

Publications and source records attributed to Hyeon Hoe Kim.

At least 19 recordsLinked to original sources
PubMed2006

Prevention of nephrolithiasis by Lactobacillus in stone-forming rats: a preliminary study.

Hyperoxaluria is a risk factor for renal stones. It appears to be sustained by increased dietary load or increased intestinal absorption. The aim of this study was to evaluate whether oral administration of lactobacilli could prevent urolithiasis in stone-forming rats. Oxalate-degrading activities of lactobacilli were evaluated by measuring the oxalate level in a culture medium after inoculation with lactobacilli. Only the strains of Lactobacillus having oxalate-degrading activity were used. Sprague-Dawley rats were fed a powdered standard diet containing 3% sodium oxalate and/or received 100 mg/kg of celecoxib for the first 8 days by gavage, before or after the beginning of this experiment (groups with previous treatment or with co-treatment). Rats were sacrificed after 4 weeks and kidneys were harvested for the assay of crystal formation under a dissecting microscope. Twenty-four-hour urine collections were performed before kidney harvest. Only two strains, Lactobacillus casei HY2743 and L. casei HY7201 out of 31 strains of Lactobacillus were able to degrade oxalate. In both groups of co-treatment and previous treatment with L. casei HY2743 and L. casei HY7201, urine oxalate excretion decreased compared to the group without lactobacilli. The dissecting microscope examination of kidneys in the rats in two previous treatment groups and the co-treatment group with L. casei HY7201 showed less abundant crystals than control groups. Our results show that lactobacilli may be used as a potential therapeutic strategy in the prevention of urinary stones.

Animals↗
PubMed2006

In vivo hepatocyte growth factor gene transfer to bladder smooth muscle after bladder outlet obstruction in the rat: a morphometric analysis.

PURPOSE: We determined whether hepatocyte growth factor gene transfer after partial bladder outlet obstruction would prove effective for decreasing transforming growth factor-beta expression and consequently decreasing collagen deposition in partially obstructed rat bladders. MATERIALS AND METHODS: Ten-week-old male Sprague-Dawley rats were divided into 3 groups of 10 each, including group 1--sham operation, group 2--bladder outlet obstruction for 4 weeks and group 3--hepatocyte growth factor gene transfer after bladder outlet obstruction. Two weeks after the onset of bladder outlet obstruction in group 3 hepatocyte growth factor-liposome complex (50 microg human hepatocyte growth factor cDNA) was injected into the smooth muscle of the rats. RESULTS: We noted no difference between groups 2 and 3 with regard to the ratio of bladder weight to body weight. The ratio in groups 2 and 3 was significantly higher than in group 1 (p = 0.043). The mean percent of collagen area +/- SE was 36.32% +/- 1.83%, 27.90% +/- 2.66% and 8.97% +/- 3.35% in groups 1 to 3, respectively (p <0.05). Relative hepatocyte growth factor and c-met mRNA and protein expression were higher in group 3 than in groups 1 and 2. However, the expression of transforming growth factor-beta1 mRNA and protein was higher in group 2 than in groups 1 and 3. CONCLUSIONS: These findings may imply a possible novel therapeutic strategy against bladder dysfunction arising in patients with bladder outlet obstruction.

Animals↗
PubMed2006

Effects of green tea on urinary stone formation: an in vivo and in vitro study.

PURPOSE: We evaluated whether epigallocatechin gallate (EGCG), a main constituent of green tea polyphenols, could protect against cellular toxicity by oxalate and whether green tea supplementation attenuates the development of nephrolithiasis in an animal model. MATERIALS AND METHODS: Cells of the NRK-52E line were incubated with different concentrations of oxalate with and without EGCG, and toxicity and malondialdehyde assays were done to investigate the cytotoxic effect of oxalate and the anti-oxalate effect of EGCG.. In a second series of experiments, male Sprague-Dawley rats were divided into three groups. Group 1 animals (controls) were fed regular chow and drank water ad libitum; group 2 animals were fed chow containing 3% sodium oxalate with the administration of gentamicin (40 mg/kg) and drank water ad libitum; group 3 animals were fed the same diet as group 2 with gentamicin administration and drank only green tea. Rats were killed 4 weeks later after a 24-hour urine collection, and the kidneys were removed for morphologic examination. RESULTS: As oxalate concentrations increased, the number of surviving cells decreased, and the formation of free radicals increased. The administration of EGCG inhibited free-radical production induced by oxalate. Green tea supplementation decreased the excretion of urinary oxalate and the activities of urinary gammaglutamyltranspeptidase and N-acetylglucosaminidase. The number of crystals within kidneys in group 3 was significantly lower than in group 2. CONCLUSIONS: Green tea has an inhibitory effect on urinary stone formation, and the antioxidative action of EGCG is considered to be involved.

Acetylglucosaminidase↗
PubMed2006

Serial microscopic changes in cell proliferation and apoptosis in obstructed ureter of rat.

PURPOSE: We investigated the histologic findings and serial changes in cell proliferation and apoptosis in obstructed rat ureters. MATERIALS AND METHODS: After unilateral ligation of the ureter, animals from each of five groups of Sprague- Dawley rats were sacrificed for examination at 1, 5, 10, 15, 20, 25, 30, or 35 days. Cell division was detected with proliferating cell nuclear antigen (PCNA) immunohistochemistry, and apoptosis was detected with terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) in-situ nick-end labeling (TUNEL) study. RESULTS: The epithelial layer was thickened in 5-day-obstructed ureters (5 DOUs). The severity of thickening of the fibrous and smooth-muscle layers progressed consistently to 15 DOUs and were maintained in 35 DOUs. Expression of PCNA in the epithelial layer was present in every ureter, and a significant increase in the number of labeled cells was present in 1 and 5 DOUs. Expression of PCNA in the fibrous and smoothmuscle layers was detectable in 10 DOUs and was maintained in 20 DOUs, after which, it declined significantly in the 25 DOUs. TUNEL-positive cells in the epithelial layer were shown in 10, 15, 20, 25, 30, and 35 DOUs, with the peak being reached at 25 days. TUNEL-positive cells in the fibrous and smooth-muscle layers were found in 25, 30, and 35 DOUs. CONCLUSIONS: Cell proliferation and apoptosis may play an important role in the pathogenesis of damage in obstructed ureters. Peak times of proliferation and apoptosis were different in the epithelial and fibrous and smooth-muscle layers.

Animals↗
PubMed2006

Laparoscopic ureteroneocystostomy with vesicopsoas hitch: nonrefluxing ureteral reimplantation using cystoscopy-assisted submucosal tunneling.

PURPOSE: We described laparoscopic nonrefluxing ureteral reimplantation with a psoas hitch using a submucosal tunneling technique combined with cystoscopy. PATIENTS AND METHODS: We performed this operation on two female patients. The first patient had a right lower-ureteral stricture after a laparoscopy-assisted vaginal hysterectomy, and the second patient had a left distal-ureteral stricture after a left laparoscopic oophorectomy, which was performed for endometriosis. We performed laparoscopic intravesical ureteral reimplantations with a psoas hitch using submucosal tunneling after a submucosal injection of normal saline was provided under cystoscopy. RESULTS: The operative times were 325 and 280 minutes, respectively. The estimated blood loss was 300 mL in the first case and 120 mL in the second. The hospital stays were 5 and 3 days, respectively. There were no postoperative complications. Follow-up voiding cystourethrography and intravenous urography demonstrated normal compliance and function of the kidneys and ureters with no vesicoureteral reflux. CONCLUSIONS: Laparoscopic intravesical nonrefluxing ureteroneocystostomy with a psoas hitch is a safe and feasible procedure. Cystoscopic submucosal injection of normal saline during submucosal tunneling is beneficial.

Adult↗
PubMed2006

Retroperitoneal laparoscopic ureterolithotomy for upper ureter stones.

We evaluated the role of retroperitoneal laparoscopic ureterolithotomy (RPLU) for upper ureter stones. Between February 1998 and July 2004, 12 patients (10 men and 2 women) underwent RPLU for upper ureter stones (mean size 18.1 mm, range 10-25). RPLU was carried out in 5 patients as a salvage treatment after failed shock wave lithotripsy (SWL) (3) and both of failed SWL and ureteroscopy (URS) (2), and in 7 patients as primary treatment for large impacted stones. Total 6 of 12 cases were converted to open surgery. The reason of open conversion was failure of locating ureter due to severe adhesion in 5 cases and vascular injury in 1 case. In 6 successful cases, mean operation time, mean estimated blood loss, and mean postoperative hospital stay were respectively 109 min (90-120 min), 50 mL (10-100 mL), 4.6 days (2-7 days). There was no serious postoperative complication except for one patient who showed delayed urinary leakage but was cured with conservative management. Our experience suggested that RPLU was not easy to perform simply because it was indicated mainly in ureter stones with severe adhesion or after failed SWL and/or URS. Nevertheless, it can be considered as a primary procedure before open ureterolithotomy.

Adult↗
PubMed2005

An animal model of calcium oxalate urolithiasis based on a cyclooxygenase 2 selective inhibitor.

Our aim was to develop a stone-forming animal model involving renal tubular injury using a cyclooxygenase 2 selective inhibitor. Male Sprague-Dawley rats fed chow containing 3% sodium oxalate with or without 100 mg/kg celecoxib were compared to animals fed normal chow. Rats were killed after 2 or 4 weeks and the kidneys were harvested for morphological examination. Collections of 24-h urine were made before kidney harvest. After 2 weeks only a few crystals were observed in rats that received oxalate and celecoxib, but after 4 weeks more crystals were observed at the renal papilla than in rats that received only oxalate. Few crystals were found in rats fed normal chow with or without celecoxib. The urinary activities of gamma-glutamyl transpeptidase (GGT) were increased by celecoxib administration whereas creatinine clearance rates were unchanged. In rats fed oxalate, urinary oxalate excretion increased, but calcium excretion decreased. This model using a cyclooxygenase 2 selective inhibitor is a useful stone forming animal model involving mild renal tubular injury together with mild hyperoxaluria.

Animals↗
PubMed2005

How painful are shockwave lithotripsy and endoscopic procedures performed at outpatient urology clinics?

Our aim was to investigate the subjective pain felt by patients during shockwave lithotripsy (SWL) and endoscopic procedures such as cystoscopy, retrograde ureteral stenting, retrograde pyelography (RGP), and ureteroscopic lithotripsy performed in an outpatient clinic, and to identify how severe pain during such procedures is. We estimated subjective pain in 984 patients after SWL (186), cystoscopy (489), retrograde ureteral stenting (127), RGP (97), and ureteroscopic lithotripsy (85) performed by a single expert in an outpatient clinic using a prospective questionnaire with a ten point visual analog scale between January 2001 and December 2003. There was no premedication in any procedure except ureteroscopic lithotripsy for which an intramuscular injection of analgesics (pethidine HCl 50 mg) was used. The pain scale score in SWL was 6.62+/-2.27, the highest among the procedures (P<0.05). Pain scores for endoscopies were 4.48+/-2.07 in retrograde ureteral stenting, 3.81+/-2.06 in ureteroscopic lithotripsy, 3.72+/-1.75 in RGP, and 3.08+/-1.95 in cystoscopy. In this study, we observed that patients feel most pain in SWL without anesthesia, and that pain during ureteroscopic lithotripsy under local anesthesia is not high, compared with other endoscopic procedures.

Adolescent↗
PubMed2005

Apoptosis induced by oxalate in human renal tubular epithelial HK-2 cells.

Oxalate is not only considered to be one of the main constituents of urinary stones, but it also has toxic effects on renal tubular epithelial cells, affecting the pathogenesis of nephrolithiasis. We tried to elucidate the effects of oxalate on human renal tubular epithelial cells (HK-2 cells). In addition, we investigated whether the toxic effect of oxalate occurs by apoptosis, and determined the expression of Bcl-2 family and caspase 9 proteins known as apoptosis-related protein. HK-2 cells were incubated with different concentrations of oxalate, and the effect of oxalate on the growth of the cells was assessed by MTT assay. A caspase-3 activity assay and TUNEL assay were performed on HK-2 cells after oxalate exposure in order to evaluate apoptosis. Immunoblot analysis of Bax, Bcl-2, Bcl-xL, and caspase-9 were performed. Oxalate exposure resulted in significant growth inhibition of HK-2 cells as oxalate concentrations increased. The toxic effect of oxalate on HK-2 cells was considered to occur through apoptosis, as suggested by the increase of caspase-3 activity. The percentage of positive nuclei stained using the TUNEL method was 18+/-2.3 in oxalate-treated cells and 2.5+/-0.9 in untreated cells (P<0.05). Bax and caspase-9 protein expression increased significantly as oxalate concentrations increased, but Bcl-2 protein expression decreased. There was no difference in Bcl-xL protein expression among the various concentrations of oxalate. Our results show that oxalate has a toxic effect on HK-2 cells and that this effect is induced by apoptosis, which may be mediated by an intrinsic pathway.

Apoptosis↗
PubMed2005

Metastasis of transitional cell carcinoma to the lower abdominal wall 20 years after cystectomy.

Iatrogenic implantation has been the main cause in the majority of cases of transitional call carcinoma (TCC) with metastasis to the abdominal wall. A 66-year-old woman had undergone radical cystectomy 20 years prior to presenting. Radiological investigations revealed one mass in the left lower abdominal wall and one mass in the right inguinal area. She underwent wide excision of the lesions that revealed metastasis of TCC. This report describes this case of a woman with bladder carcinoma who developed a metastasis in the anterior abdominal wall following an apparent disease-free interval of 20 years.

Abdominal Wall↗
PubMed2005

Direct ureteric length measurement from intravenous pyelography: does height represent ureteric length?

Ureteric length is the most important factor for determining the ideal length of a ureteric stent. In most of the literature, ureteric length is estimated according to a patient's height. We investigated the reliability of a patient's height as a measure of ureteric length. We measured the actual length of the ureteric trace (ALUT) and the linear distance (LD) from the ureterorenal junction to the ureterovesical junction by intravenous pyelography (IVP), using a 15 min view. A total of 203 patients (100 men, 103 women, 406 ureters) with normal findings were studied, and ALUT, LD and height were measured. The mean patient height was 164.3 +/- 8.3(SD) cm. Mean ALUTs of the right and left ureters were 23.4 +/- 1.9 cm and 24.4 +/- 2.0 cm, respectively, and the mean LDs of the right and left ureters were 22.1 +/- 1.9 cm and 22.9 +/- 2.0 cm, respectively. Height was significantly correlated with the ALUTs of both sides, but these were not linear (r2 = 0.024 right, 0.059 left). However, LD showed significant linear correlations with the ALUTs of both sides (r2 = 0.879 right, 0.884 left). Two formulas to estimate the ALUT from LD were suggested: right ALUT = 0.94 x right LD + 2.6, left ALUT = 0.96 x left LD + 2.4. Our results demonstrated that patient height does not provide a reliable estimate of ureteric length. LD by IVP is preferable to patient height when estimating the ureteric length.

Adolescent↗
PubMed2005

Involvement of Rho-kinase in the contractile mechanism of human ureteral smooth muscle.

AIM: Even though many agents have been implicated as modulators of ureteral contractile activity, the exact mechanisms that control human ureteral smooth muscle contractility have yet to be clearly defined. Recently, Rho-kinase has been reported to be involved in the contractile mechanism of smooth muscles in various organs. In the present study, we sought to investigate whether or not Rho-kinase is expressed in the human ureteral smooth muscle, and to study its role regarding human ureteral smooth muscle contractility. METHODS: Ureteral samples were obtained from human adult subjects undergoing radical nephrectomy. Immunohistochemistry and Western blotting were performed to determine the presence of Rho-kinase in human ureter. Functional studies were performed with human ureteral strips suspended in organ bath, and the effects of Y-27632, a specific inhibitor of Rho-kinase, on baseline tensions, spontaneous contractions, and electrical field stimulation (EFS)-induced contractions were analyzed. RESULTS: The results of immunohistochemistry and immunoblotting study indicated that Rho-kinase is present in human ureteral smooth muscle. In functional analysis, Y-27632 was shown to decrease the baseline tension. And, both spontaneous and EFS-induced contractile responses of human ureteral strips were attenuated by Y-27632 in dose-dependent manners. CONCLUSIONS: For the first time, the results of the present study indicate that Rho-kinase is present in human ureteral smooth muscle and may play an important role in the intricate mechanism of human ureteral contractility and tone.

Adult↗
PubMed2005

Laparoscopic nephrectomy for renal diseases in children: is there a learning curve?

BACKGROUND/PURPOSE: We evaluated the impact of a surgeon's experience, divided our first 20 consecutive series that involved a single surgeon at the numerical midpoint of his experience, and compared outcomes regarding this midpoint. METHODS: From August 1996 to August 2001, laparoscopic nephrectomy or nephroureterectomy was performed in 20 consecutive children, 12 girls and 8 boys aged between 1 and 15 years (median, 5.9 years). Disease was in the right side in 11 patients and in the left side in 9. The children were divided into 2 groups of 10. We retrospectively obtained data on all patients and compared pertinent perioperative information including operation time, blood loss, length of hospital stay, and postoperative complications. RESULTS: The procedure was feasible in all cases and did not require conversion to open surgery or perioperative transfusion in any case. The operation time reduced from a median of 181 minutes over the first 10 patients to 125 minutes over the second 10, and this difference was significant (P = .02). Estimated blood loss and days to the first postoperative oral feeding for the second 10 patients were less than for those of the first 10 but there was no significant difference. The median hospital stay of the first 10 patients was 5.4 days (range, 2-10 days), significantly longer than the 2.5 days of the second 10 (range, 2-7 days) (P = .009). CONCLUSIONS: Laparoscopic nephrectomy operation times in children reduced when the surgical experience level exceeded approximately 10 cases.

Adolescent↗
PubMed2005

Hand-assisted laparoscopic and open living donor nephrectomy in Korea.

BACKGROUND: We compared the results of hand-assisted laparoscopic living donor nephrectomy (LLDN) and conventional open living donor nephrectomy (OLDN). METHODS: The clinical data on 49 hand-assisted LLDN and 21 OLDN on the left side performed at two institutions in Korea from January 2001 to February 2003 were reviewed. Demographic data of donors and recipients were similar in the two groups. RESULTS: There was one conversion to an open procedure due to bleeding in the LLDN group. The median operation times (180 min in LLDN versus 170 min in OLDN) and warm ischemic times (2.5 min in LLDN versus 2.0 min in OLDN) in the two groups were similar. The estimated mean blood loss, duration of hospital stay and complication rate was also similar in the two groups. The LLDN group reported less pain (visual analog scale) postoperatively (4.1 versus 5.3), but this was not significant (P=0.058). The time to oral intake in the LLDN group was significantly longer by an average of 1 day (P=0.001). Return to work was sooner in the LLDN group (4.0 weeks versus 6.0 weeks; P=0.026). The recipient graft function was equivalent between the two groups. Hand-assisted LLDN appears to be a safe and effective alternative to OLDN. CONCLUSION: Our findings suggest that this technique may give the ability provide grafts of similar quality to OLDN, while extending to the donors the advantages of a traditional LLDN procedure.

Adult↗
PubMed2005

Systemic chemotherapy in patients with indwelling ureteral stenting.

BACKGROUND: We investigated whether systemic chemotherapy increased episodes of acute pyelonephritis (APN) in patients with an indwelling double-J stent due to non-urological malignant ureteral obstruction. METHODS: A retrospective study was performed on a total of 74 patients (16 men and 58 women; median age, 53.0; range, 34-84 years) with non-urological malignant ureteral obstruction, who were managed by double-J stenting between October 1997 and December 2001. The patients were divided into those who received (33 patients, group I) and those who did not receive systemic chemotherapy (41 patients, group II) during the stent indwelling period (median, 7.0; range, 1-44 month). Routine antibiotic prophylaxis was not administered to any patient. Median follow-up was 10.5 (range, 1-45) months. Clinical features, including the incidence of febrility and APN, were compared between the two groups. RESULTS: Of the 74 patients, 18 patients (24.3%) experienced acute febrile episodes during ureteral stenting, but only five (6.8%) patients were diagnosed as having APN. No significant difference in the incidence of fever or APN was found between the two groups (P = 1.000 and P = 0.651, respectively). Univariate logistic analysis indicated that only the duration of follow-up was a risk factor for an episode of fever. Other parameters had no clinical significance. CONCLUSION: Our findings suggest that systemic chemotherapy may not predispose the risk of acute pyelonephritis in patients with an indwelling ureteral stent due to non-urological malignant ureteral obstruction.

Acute Disease↗
PubMed2005

Laparoscopic nephrectomy for congenital benign renal diseases in children: comparison with adults.

AIM: To compare the results of laparoscopic nephrectomy for congenital benign renal diseases in children and adults. METHODS: From August 1996 to February 2003, laparoscopic nephrectomies were performed on 26 children and 60 adults. Of these patients, 33 patients (17 children, 16 adults) with comparable diseases were included in the analysis. RESULTS: Disease was on the right side in 16 patients and on the left in 17. Operative and convalescence parameters, including operative time, blood loss, transfusion rate, conversion rate to open surgery, resumption of oral intake, hospital stay, and complication rate, were evaluated in both groups. Median operative time in the paediatric group was 140 min compared to 147.5 in adults (p=0.626). The estimated blood loss was significantly different (median 25 and 75 cm(3) in children and adults, respectively; p<0.001). Other operative and convalescence parameters were not statistically different. However, whereas no child required a blood transfusion, three adults (18.8%) did. No major perioperative complications occurred in the paediatric group, but open surgical exploration was needed due to retroperitoneal bleeding in a single adult. CONCLUSION: Our findings indicate that laparoscopic nephrectomy for congenital benign disease in children is achieved safely and that the modality offers additional advantages in children as compared to adults.

Adult↗