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Biomedical subjects

K S Cho

Publications and source records attributed to K S Cho.

At least 73 records · Page 4Linked to original sources
PubMed1996

Effects of polyglactin mesh combined with resorbable calcium carbonate or replamineform hydroxyapatite on periodontal repair in dogs.

This study evaluates periodontal repair and biomaterial reaction following implantation of a polyglactin mesh with or without porous resorbable calcium carbonate (RCC) or porous replamineform hydroxyapatite (RHA) in conjunction with reconstructive surgery. Ligature- and surgically-induced interproximal periodontal defects of left and right mandibular premolar teeth in 7 dogs were used. Bilaterally, mesial defects of the 2nd, 3rd and 4th premolar teeth were treated with polyglactin mesh, polyglactin mesh and RHA, or polyglactin mesh and RCC, respectively. The polyglactin mesh, shaped according to the contour of the defect, was adapted to the experimental teeth; its coronal margin positioned immediately apical to the cemento-enamel junction. Gingival flap margins were adapted and sutured to cover the polyglactin mesh completely. Clinical healing was generally uneventful. The dogs were sacrificed to provide block sections for histologic evaluation at 1, 3, 6, 12, 26, 32 and 56 weeks following wound closure. Generally, cementum regeneration was observed beginning at week 6 in all groups. Bone regeneration was observed from week 3 in polyglactin mesh-treated groups, and from week 6 in polyglactin mesh+RCC or polyglactin mesh+RHA treated groups. Bone regeneration appeared enhanced in polyglactin mesh+RCC or polyglactin mesh+RHA treated defects at week 12 and 26, with little difference between the three experimental conditions at week 56. Polyglactin mesh degradation was observed at week 3 and appeared complete at week 12. The RHA did not appear to resorb, while the RCC was gradually replaced by bone from week 3. Within limitations of the study conditions, periodontal regeneration was observed following implantation of a polyglactin mesh with or without RCC or RHA in conjunction with reconstructive surgery. As a conclusion, there seems to be no significant difference in periodontal regeneration after 12 months of healing between the group treated with the membrane only, and the group treated with the membrane and the bone substitution material. Changes in connective fiber orientation over the 1st 12 weeks of healing may suggest that "fibrous encapsulation" observed in earlier studies may only represent a transient stage in periodontal regeneration.

Animals↗
PubMed1996

Periodontal repair in intrabony defects treated with a calcium carbonate implant and guided tissue regeneration.

Clinical outcome following the concurrent use of a porous resorbable calcium carbonate (CC) implant and guided tissue regeneration (GTR) in intrabony periodontal defects was evaluated in a randomized four-treatment parallel arm study. Eighty (80) patients, each contributing one interproximal intrabony defect, were assigned to the four treatments (20 patients per treatment) including the CC implant and GTR (CC + GTR), GTR alone (GTR control), CC implant alone (CC control), and gingival flap surgery alone (GFS control). Fourteen patients treated with CC + GTR, 19 patients treated with the GTR control, 13 patients treated with the CC control, and 18 patients treated with the GFS control completed the study. Clinical healing was evaluated 6 months postsurgery and included changes in probing depth, clinical attachment level, probing bone level, and gingival recession. Postsurgery probing depth reduction was 4.5 +/- 1.7 mm (CC + GTR; P < 0.01), 4.8 +/- 1.8 mm (GTR; P < 0.01), 3.7 +/- 2.2 mm (CC; P < 0.01), and 3.3 +/- 1.6 mm (GFS; P < 0.01). Clinical attachment gain amounted to 3.3 +/- 1.4 mm (CC + GTR; P < 0.01), 4.0 +/- 2.1 mm (GTR; P < 0.01), 3.0 +/- 2.4 mm (CC; P < 0.01), and 2.0 +/- 1.7 mm (GFS; P < 0.01). The CC + GTR and GTR treatments exhibited significantly greater improvements compared to GFS (P < 0.05). Postsurgery probing bone level gain amounted to 4.0 +/- 1.7 mm (CC + GTR; P < 0.01), 4.1 +/- 1.5 mm (GTR; P < 0.01), 4.0 +/- 2.2 mm (CC; P < 0.01), and 0.5 +/- 2.0 mm (GFS; P > 0.05). The CC + GTR, GTR, and CC treatments exhibited significantly greater improvements compared to GFS (P < 0.05). Gingival recession increased significantly compared to presurgery for GTR, CC, and GFS treatments (-0.9 +/- 1.2, -0.7 +/- 0.7, and -1.2 +/- 1.4 mm, respectively; P < 0.01). The results suggest that the concurrent use of a porous resorbable CC implant and GTR has limited adjunctive effect in the treatment of intrabony periodontal defects.

Adult↗
PubMed1996

Induction chemotherapy with idarubicin plus N4-behenoyl-1-beta-D-arabinofuranosylcytosine in acute myelogenous leukemia: a newly designed induction regimen--a prospective, cooperative multicenter study.

This report describes the results of induction chemotherapy with idarubicin (IDA) plus N4-behenoyl-1-beta-D-arabinofuranosylcytosine (BH-AC), a newly designed induction regimen, in cases of previously untreated acute myelogenous leukemia (AML). The study was conducted by the Multicenter Clinical Study Group of the Korean Biologic Response Modifier Society (KBRMS). From March 1994 through January 1995, 40 patients were treated. The median age was 30 years (range, 15 months to 65 years), with a distribution according to the French-American-British (FAB) classification of one MO, nine MI, 15 M2, six M3, four M4, and five M5 patients. Remission induction therapy consisted of IDA 12 mg/m2 intravenously (i.v.) over 30 minutes daily on days 1 to 3, in combination with BH-AC 300 mg/m2 over 4 hours daily on days 1 to 7 (in patients aged 41 to 65 years, BH-AC dosage was decreased to 200 mg/m2/d). Complete remission (CR) was achieved in 30 patients (75%), 22 by the first induction therapy and eight by the second induction therapy. Ten patients (25%) failed to respond to therapy, six due to resistant disease and four due to death caused by aplasia. The time to CR was 30 days, the median granulocytopenic period was 19 days, and the thrombocytopenic period was 24 days. All nonhematologic side effects such as nausea, vomiting, mucositis, skin eruption, liver and cardiac dysfunction, and neurotoxicity, were transient and tolerable. These data indicate an efficacy comparable to that of other combinations of IDA (or other anthracyclines) with cytosine arabinoside (Ara-C) for remission induction in AML.

Adolescent↗
PubMed1995

Analysis of mutations of neurofibromatosis type 1 gene and N-ras gene in acute myelogenous leukemia.

Neurofibromatosis type 1 (NF1) gene is a tumor suppressor gene, and the NF1 gene product, neurofibromin, can downregulate the N-ras gene. Because the N-ras gene is often mutated in acute myelogenous leukemia (AML), we wondered if the NF1 gene might be mutated in those AML samples not having N-ras mutations. We investigated the mutational status of the N-ras gene and the FLR exon of codons 1371-1423 of the open reading frame of the full-length NF1 cDNA, which has a strong homology with the mammalian ras GTPase-activating protein (GAP), especially for a stretch of three consecutive amino acids (F, L, R), by single-strand conformation polymorphism analysis and direct sequencing in samples from patients with AML. Of 48 AML patients, 10 (21%) had point (missense) mutations of the N-ras gene involving codons 12, 13 and 61. However, mutations in the FLR exon of the NF1 gene were not detected in any of the AML samples. We also examined the difference of clinical response to induction therapy between AML patients with and without N-ras mutation. A significantly lower rate of complete remission was noted in individuals with N-ras gene mutations. These results suggest that mutation of the NF1 gene, at least in the FLR exon, is very rare in AML and the NF1 gene probably is not a functional complement of the N-ras gene mutation. The presence of N-ras gene mutation may be associated with a lower clinical response to antileukemic therapy.

Adult↗
PubMed1995

Self-expandable metallic stents in high-risk patients with benign prostatic hyperplasia: long-term follow-up.

PURPOSE: To evaluate the long-term clinical utility of self-expandable metallic Z stents in benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: Under fluoroscopic guidance, 14 multiple-connected Z stents (10 mm in diameter fully expanded, 30-60 mm in length) were placed in 13 patients with bladder obstruction from BPH and high operative risks. The stents were placed in the prostatic urethra with 2-20-mm protrusion into the urinary bladder in six patients (group A) and entirely within the prostatic urethra in seven patients (group B). RESULTS: Eleven of 13 patients could void immediately, and the other two patients with atonic bladder voided within 8 weeks. Maximum urine flow rates just after stent placement were 8-27 mL/sec. Two patients died of unrelated causes within 2 months. During the follow-up period (mean, 37 months) in the other 11 patients, all patients in group A but none in group B underwent surgery owing to stone formation where the stent protruded into the bladder. CONCLUSION: Expandable Z stents are effective in patients with BPH but should not protrude into the urinary bladder because of stone formation.

Aged↗
PubMed1995

Safety of intravitreally injected ciprofloxacin in phakic rabbit eyes.

This study was designed to determine the maximal safe drug concentration of intravitreal ciprofloxacin in phakic rabbit eyes. Twenty-two eyes of New Zealand pigmented rabbits received midvitreal ciprofloxacin of 100, 200, 400, 600 or 800 micrograms in BSS Plus, or BSS Plus only. Retinal toxicity was dose-dependent as determined with electroretinography, light microscopy, and transmission electron microscopy. At a dose of greater than 400 micrograms, disorganization of the outer segments was a main pathological finding in transmission electron microscopy. We evaluated retinal function by measuring the electroretinograms for a graded series of flash intensities and by fitting electroretinogram b-wave amplitudes to the Naka-Rushton equation. At a dose of greater than 600 micrograms, Rmax was significantly decreased and log K was significantly increased. N-value tended to decrease. A decrease of b-wave amplitudes caused by retinal toxicity could be detected very sensitively with lower luminance stimuli. Determination of retinal toxicity with lower luminance electroretinography revealed a significant decrease of b-wave amplitudes at a dose of greater than 400 micrograms. We concluded that a safe dose of intravitreal ciprofloxacin in phakic rabbit eyes was 200 micrograms in phakic eyes.

Animals↗
PubMed1995

[Occupational medicine services in small enterprises].

The article deals with the materials of International Symposium on Industrial Medicine, which was held in November '93 in Seul (South Korea). Participated by scientists from Finland, China, Hong Kong, Russia, WHO, the Symposium was devoted to 30th Anniversary of Korean Industrial Hygienic Association. The main items discussed were importance of occupational medical control in small enterprises (including also farms, fishing firms and public service offices), as they appear to have unfavourable work conditions (noise, high concentrations of chemicals, heating microclimate). Improved regulation of industrial medicine and developed primary care service were also stressed expedient. Special emphasis involved basic science for industrial hygiene and better professional training.

Congresses as Topic↗
PubMed1994

Loculated fluid collections in hepatic fissures and recesses: CT appearance and potential pitfalls.

The peritoneum invaginates into the liver parenchyma normally, as a normal anatomic variation, or pathologically and then fissures and furrows are formed. There are four normal fissures: fissures for the ligamentum teres, ligamentum venosum, and gallbladder and the transverse fissure. Fissures caused by normal anatomic variations include accessory fissures and furrows created by diaphragmatic indentation. Pathologic fissures occur secondary to traumatic or iatrogenic causes or as a result of liver cirrhosis. When ascites, hemoperitoneum, or infected ascites is loculated in the fissures or recesses, it may be mistaken for a liver cyst, intrahepatic hematoma, or liver abscess. When peritoneally disseminated tumor cells are implanted into these spaces, they may mimic intrahepatic focal lesions. Because the clinical consequences for these entities are very different, exact localization of the lesions may be crucial in the diagnosis and management of the lesions. Complete understanding of the liver surface anatomy and awareness of these situations may prevent a misdiagnosis of a focal intrahepatic abnormality.

Humans↗
PubMed1994

In vitro MR imaging of the resected stomach with a 4.7-T superconducting magnet.

PURPOSE: To study the effects of formalin fixation, signal intensity characteristics of the stomach-wall layers, and findings suggestive of cancerous invasion to the stomach wall in vitro with magnetic resonance (MR) imaging in humans. MATERIALS AND METHODS: MR images of nine specimens of stomach cancer and 29 normal specimens were obtained at 4.7 T; 26 of the normal specimens were fixed in 10% formalin for 2 hours to 187 days before imaging. The field gradient was 10 G/cm; the spatial resolution, 0.1 mm. RESULTS: The mucosal, submucosal, and proper-muscle layers were clearly identifiable. The submucosa of the fresh specimens had the lowest signal intensity of all specimens on both T1- and T2-weighted images (P < .01). No statistical correlation existed between signal intensity and duration of fixation. Tumor invasion was detected in seven of eight specimens with mucosal invasion, all eight specimens with submucosal invasion, and three of six specimens with muscle invasion. CONCLUSION: In vitro MR imaging enabled differentiation of all three layers of the stomach wall, detection of the cancer, and measurement of the depth of invasion.

Formaldehyde↗
PubMed1994

Clinical value of DMSA planar and single photon emission computed tomography as an initial diagnostic tool in adult women with recurrent acute pyelonephritis.

Routine DMSA scintigraphy, ultrasound (US) of the kidney, intravenous pyelography (IVP) and voiding cystoureterography (VCU) were performed in 27 consecutive adult women with recurrent acute pyelonephritis (APN) during a 12-month follow-up. Both planar and single photon emission computed tomography (SPECT) images were obtained for DMSA scan. DMSA scans were repeated in those patients with abnormal initial scan. DMSA-SPECT showed normal findings in 2, single renal cortical detect (RCD) in 9 and multiple RCD in 16 (including nonvisualization in 2). Of the 11 kidneys with normal findings or single RCD on DMSA-SPECT, only 1 (9%) showed vesicoureteral reflux (VUR) on VCU (grade I). A large proportion of those with multiple RCDs showed abnormal findings on IVP (44%, 7/16), US (38%, 6/16) or VCU (31%, 5/16); 63% in any of these three studies. 5 of 6 patients with VUR had multiple RCDs on DMSA-SPECT, and 3 of these 5 showed no abnormality on IVP or US. 7 patients who needed other managements besides initial standard antibiotic treatment had multiple RCDs on DMSA-SPECT. 15 normal women were also studied and showed normal DMSA-SPECT, US and IVP, in all cases. Follow-up DMSA-SPECT was done in 16 patients (7 with single RCD, 9 with multiple RCD). All 7 patients with single RCD showed improvement, in those with multiple RCDs improvement was observed in 2, no change in 7 on follow-up studies. We conclude: (1) DMSA-SPECT is a useful initial diagnostic tool in adult women with recurrent APN to identify patients who need more extensive radiological studies.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Tuberculous epididymitis and epididymo-orchitis: sonographic findings.

The findings at scrotal sonography in 10 patients with tuberculous epididymitis and in 2 with nontuberculous epididymitis are presented. In 6 patients with tuberculous epididymitis the testes were also involved (epididymo-orchitis). The most notable sonographic findings of tuberculous epididymitis were an enlarged epididymis, predominantly in the tail portion, and marked heterogeneity of the echo texture of the involved epididymis. Sonographic findings of associated testicular involvement consisted of a diffusely enlarged hypoechoic testis or ill defined focal intratesticular hypoechoic areas, or an irregular margin between the testis and epididymis. The sonographic findings encountered in patients with tuberculous epididymitis appear to be different from those encountered in nontuberculous epididymitis. Sonography might prove helpful in aiding the clinical distinction between these 2 forms of epididymitis and in demonstrating associated testicular involvement in tuberculous epididymitis.

Adult↗
PubMed1993

Therapeutic percutaneous aspiration of hepatic abscesses: effectiveness in 25 patients.

OBJECTIVE: The objective of this study was to evaluate the effectiveness of sonographically guided needle aspiration and systemic antibiotic therapy for the treatment of hepatic abscesses. SUBJECTS AND METHODS: From June 1989 to September 1991, sonographically guided needle aspiration and systemic antibiotics were used to treat 25 consecutive patients with 25 hepatic abscesses. Among 36 patients with hepatic abscesses who were admitted to the hospital during that time, six had antibiotic therapy only; of these, three had microabscesses, two had abscesses less than 3.0 cm in diameter, and one refused needle aspiration. Four patients had surgical external drainage (three had cholelithiasis in addition to hepatic abscesses, and one did not respond to needle aspiration). Two patients treated in 1989 had drainage via an indwelling catheter, which was the preferred method at that time. The remaining 24 patients and one patient who had needle aspiration followed by surgical drainage made up the study group. Seventeen of the hepatic abscesses were caused by pyogenic organisms, six by amoeba, and two by unknown organisms. Eighteen abscesses (72%) were aspirated once, four (16%) were aspirated twice in 8 days, two (8%) were aspirated three times in 14 days, and one (4%) was aspirated four times in 10 days. Persistent fever, pain and tenderness in the right upper quadrant, and leukocytosis were the indications for multiple aspirations. Follow-up sonography was performed to evaluate the outcome of treatment. RESULTS: In 16 cases (64%), the abscesses disappeared within a mean of 84 days. In eight cases (32%) with only partial follow-up, the patients were asymptomatic at the time of discharge and the abscesses were markedly smaller on the last follow-up sonograms (mean, 43 days). One patient (4%) did not respond to aspiration and had surgical drainage. The length of hospitalization varied from 5 to 42 days (mean, 22 days). In patients who became afebrile during the treatment, the fever had lasted from 0 to 10 days (mean, 3 days). Only one patient had a complication of the procedure, a pleural effusion that was treated conservatively. CONCLUSION: Our results show that sonographically guided needle aspiration combined with antibiotic therapy is effective as the initial treatment for hepatic abscesses.

Adult↗
PubMed1993

Primary breast lymphoma.

We report the case of a 20-year-old female with lymphoma of the breast. Mammography showed an asymmetric pattern of confluent densities without any discrete mass. Sonography revealed diffuse heterogenous echoic mass intermingled with low-and medium level echoes. We present the clinical, radiographic and histologic features of primary breast lymphoma with a brief review of the literatures.

Adult↗
PubMed1992

Degradation of hydrogen sulfide by Xanthomonas sp. strain DY44 isolated from peat.

Xanthomonas sp. strain DY44, capable of degrading H2S, was isolated from dimethyl disulfide-acclimated peat. This bacterium removed H2S either as a single gas or in the presence of the sulfur-containing compounds methanethiol, dimethyl sulfide, and dimethyl disulfide. The maximum specific H2S removal rate, obtained in the late stationary phase, was 3.92 mmol g of dry cells-1 h-1 (6.7 x 10(-16) mol cell-1 h-1) at pH 7 and 30 degrees C through a batch experiment in a basal mineral medium. Since Xanthomonas sp. strain DY44 exhibited no autotrophic growth with H2S, the H2S removal was judged not to be a consequence of chemolithotrophic activity. By using X-ray photoelectron spectroscopy, the metabolic product of H2S oxidation was determined to be polysulfide, which has properties very similar to those of elemental sulfur. Autoclaved cells (120 degrees C, 20 min) did not show H2S degradation, but cells killed by gamma-irradiation and cell extracts both oxidized H2S, suggesting the existence of a heat-labile intracellular enzymatic system for H2S oxidation. When Xanthomonas sp. strain DY44 was inoculated into fibrous peat, this strain degraded H2S without lag time, suggesting that it will be a good candidate for maintaining high H2S removability in the treatment of exhaust gases.

Biodegradation, Environmental↗
PubMed1992

Extracorporeal shockwave lithotripsy of primary intrahepatic stones.

Extracorporeal shockwave lithothripsy (ESWL) was performed in intrahepatic stone patients (n = 18) by Dornier MPL 9,000 with ultrasound guidance. The patients had T-tube (n = 9) or percutaneous transhepatic biliary drainage tube (n = 9). Average treatment session was four and shock-wave numbers were in the range of 3,064 to 12,000 (average 6,288 shocks). Intrahepatic stones were removed completely in 16 patients over a 3 month period by ESWL and combined stone extraction maneuver such as cholangioscopic or interventional radiologic method. Extracorporeal shockwave lithothripsy was very helpful in facilitating extraction of stones in unfavorable locations or located above the severe stricture. In summary, extracorporeal shockwave lithotripsy, followed by percutaneous stone extraction, will provide an improvement in the success rate and duration of treatment required for complete removal of primary hepatolithiasis.

Bile Ducts, Intrahepatic↗
PubMed1991

Computed tomographic analysis of gallbladder stones: correlation with chemical composition and in vitro shock-wave lithotripsy.

The recent advent of nonsurgical treatment for gallstones requires accurate in vivo analysis of their chemical composition in order to select the best candidates. As a preliminary work, we undertook an in vitro CT examination of 53 surgically removed gallstones and compared their CT patterns with their chemical composition. Those results were correlated with in vitro lithotripsy of the gallstones. The CT appearances were classified as follows: laminated (43%), dense (32%), rimmed (11%), isodense (8%) and faint (6%). The dense pattern contained a high calcium content. As the CT density increased, the calcium content increased, but the cholesterol content decreased proportionally. The number of shock waves needed to break down a gallstone less than 2 mm in size increased with stone volume and the cholesterol content increased but did not have any correlation with the calcium content level. As a result we found the CT examination to be a very sensitive method in detecting small amounts of calcium content in gallstones and the CT pattern and density of the gallstones were well correlated with their chemical composition, therefore in vivo CT examinations for ESWL candidates are desirable.

Calcium↗
PubMed1990

[A study on the nurse's response for the clinical application of nursing diagnosis].

Although the usefulness and importance of clinical application of nursing diagnosis are well recognized by the academic circle, it is not yet generally practiced. In order to provide data for establishing a policy for clinical nursing diagnosis; a study was made at a seminar, sponsored by the Department of nursing, Severance Hospital, with participation of 190 nurses from 33 hospitals. The objective of the study was to find out: 1) if the nurses agree with the academic community in recognizing the benefits and problems of clinical application of nursing diagnosis; 2) how the nurses evaluate their ability to carry out nursing diagnosis; and 3) if educational programs would help enhance ability of nursing diagnosis among nurses. The summary of findings by the study is as follows: 1. While all nurses responded positively on the question of benefits improving science and quality of nursing, thus elevating credibility and position of nurses, some expressed concern on the practicality of the system in setting up nursing objectiveness, confirming the nursing problems and utilizing patient information. For the 20 questions and the scale of 1-5, the lowest average score was 3.223 and the highest 4.066. 2. The study attempted to find out the opinion of the nurses on the problems that would make difficult to adopt the nursing diagnosis in clinics. The result of the study indicates the nurses believe the major problems are the fact that the subject of nursing diagnosis are not well defined and that the form sheets do not match with the ones that are currently being used. However, comparing it with the result of the previous study on the same question (inadequate manpower and insufficient time allocated for the job were two major problems pointed out then). It can be said that the opinion of the nurses studied this time was much more positive and it suggests that they believe the system can be adopted without increasing manpower and only by giving additional training and by adjusting the format of nursing record sheets. It suggests that the future for adopting a clinical nursing diagnosis is very bright. 3. As the most urgent problem to be solved for adopting clinical nursing diagnosis, 38. 5% responded that it was "education of nurses", and 34.2% responded that it was "staffing adequate number of nurses". 4. For the 10 questions asked for self-evaluation of ability to adopt the system, with the scale of 1-5, average score was lower than 3.(ABSTRACT TRUNCATED AT 400 WORDS)

Education, Nursing, Continuing↗