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Biomedical subjects

W H Kim

Publications and source records attributed to W H Kim.

At least 163 records · Page 9Linked to original sources
PubMed1992

Differential pattern of perivascular type IV collagen deposits in phyllodes tumors of the breast.

Deposition of basement membrane extracellular matrix is influenced by adjacent tumor cells, and in some cases, the pattern of type IV collagen deposit is characteristic in malignant tumors. In this report, we analyzed the difference in type IV collagen deposition patterns between benign and malignant phyllodes tumors (PTs) of the breast. Of the 15 cases of PTs, 8 cases were benign PTs and 7 cases were malignant PTs. Three cases of other primary sarcomas of the breast (stromal sarcoma, angiosarcoma and osteosarcoma) and 2 cases of fibroadenomas were studied for comparison. The malignant PTs were distinguished from benign ones by increased mitotic figures, cellular atypism, and a higher proliferation index of stromal cells. Immunohistochemical staining against type IV collagen in malignant PTs revealed extensive to moderate deposition of type IV collagen around the small blood vessels in duplicate or multilayering pattern, while benign PTs showed minimal deposition in a single linear pattern. All of the three cases of other sarcomas revealed multilayering or meshwork pattern of type IV collagen around the blood vessels. The deposition of type IV collagen around the blood vessels may reflect the malignant behavior of the stromal tumors of the breast.

Adult↗
PubMed1992

[An imported human case of hookworm infection with worms in the rectum].

An imported case of rectal hookworm infection was diagnosed by stool examination and recovery of adult worms from the rectal mucosa by sigmoidoscopy. The chief complaints of a patient were diarrhea, abdominal pain and weight loss for about 1 month after returning from his travel abroad to the Southeast Asia. Leukocytosis(16,750/microliters) and peripheral eosinophilia(33.7%) were noticed without anemia. Typical hookworm eggs were detected by stool examination, and 3 worms were collected by sigmoidoscopy from rectal mucosa of this patient. Those worms were confirmed as adult worms of Ancylostoma duodenale(male:1, female:2) based on their morphological characteristics. The symptoms were relieved after treatment with anthelmintics. This case was considered as one of the imported parasitic infections in Korea, and a rare case of hookworm infection on human rectal mucosa.

Ancylostoma↗
PubMed1992

Gastric varices: diagnosis with duplex Doppler ultrasonography--a case report.

The diagnosis of gastric varices may be difficult due to their anatomic location and morphology. In this abstract we describe a case of gastric varices, of which a duplex Doppler sonography was useful in the diagnosis, that was initially suggested as submucosal tumor of the stomach by barium studies and endoscopy.

Aged↗
PubMed1992

Histologic study of chronic active hepatitis C; comparison with chronic active hepatitis B.

Reports on the histologic findings of chronic active hepatitis C (CAH-C) have been rare, and the characteristic histologic findings of CAH-C have been not yet determined. To compare the differences in the histologic findings between CAH-C and chronic active hepatitis B (CAH-B) group, we analyzed the histologic findings of 19 patients with CAH-C, who had positive tests for HCV-antibody by EIA, and 19 patients with CAH-B who had negative tests for HCV-antibody but positive tests for HBsAg by RIA. Histologic features were analyzed between the CAH-C and CAH-B groups using a scoring system which is modified from Knodell's histologic activity index-looking at portal inflammation, periportal necroinflammation, portal fibrosis, focal necrosis, regeneration, polyploid nuclear change, sinusoidal lymphocytic reaction and fatty change. Portal inflammatory cell infiltrations with prominent lymphocytes and follicular arrangement were more frequent in the CAH-C group (10 of 19 cases) than in the CAH-B group (5 of 19 cases). Severe sinusoidal lymphocytic reactions were also more prominent in the CAH-C group (11 of 19 cases) than in the CAH-B group (6 of 19 cases). However, periportal necroinflammation, portal fibrosis, focal hepatic necrosis, regeneration and polyploid nuclear changes were more prominent in the CAH-B group than in the CAH-C group. In conclusion, follicular portal inflammation and severe sinusoidal lymphocytic reactions were common histologic findings in serologically proven CAH-C when compared to CAH-B.

Adult↗
PubMed1991

Ossification of the N-methyl-N'-nitro-N-nitrosoguanidine-induced small intestine adenocarcinomas in rats.

Eighty rats out of 233 developed malignant tumors in the stomach and small intestine by administration of 100 micrograms/ml N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in drinking water for 28 weeks. Fifteen lesions (30%) among the 50 small intestinal carcinomas showed ossification in the tumor, while none in the sarcomas (12 lesions) or gastric adenocarcinomas (59 lesions) showed ossification. Multifocal heterotopic bone formation was found within stroma in close approximation to the neoplastic glands. The islands of bone trabeculae were covered by osteoblast-like cells, and abundant fibroblasts in loose stroma gathered around the bony islands which enclosed osteocytes in lacunae. Neither osteoclast nor cartilage was identified. In 5 cases, ossification was extensive, which comprised the major portion of the stroma. In contrast, intraluminal calcification without ossified foci were occasionally seen in the gastric carcinoma. Ossification of the intestinal tumors correlated to the degree of mucin content (p < 0.05, chi square with Yates' correction), degree of neutrophilic infiltration (p < 0.05), and size of the tumor (p < 0.1). (The average size of the ossified tumor was 21.5 +/- 4.0 mm, while that of nonossified tumors was 12.5 +/- 1.9 mm). The degree of tumoral necrosis, desmoplasia or depth of invasion did not seem to be related to the ossification of the tumor. The ossification rate of this experimental model was much higher than in human cases. Various histologic alterations, such as mucin leakage, inflammatory cell infiltration, necrosis and/or fibrosis, which might be caused by continuous stimulation of the strong carcinogen, may play some role in the ossification of experimental tumors.

Adenocarcinoma↗
PubMed1990

Neoplastic Paneth cells in the experimental murine carcinoma of the small intestine.

The purpose of this study is to elucidate the participation of Paneth cells in experimentally induced adenocarcinoma of the intestine. The rats were fed with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) dissolved in drinking water ad libitum at a concentration of 100 micrograms/ml for 28 weeks. They were sacrificed 12 weeks after the last MNNG administration. A number of tumor cells containing large eosinophilic granules in their supranuclear cytoplasm (Paneth cells) were observed in about 20% of the experimentally induced adenocarcinoma of the small intestine. The granules were stained positively with Lendrum, periodic acid-Schiff, Masson's trichrome, and Mallory's phosphotungstic acid hematoxylin. Ultrastructurally, the granules were round, osmiophilic, and relatively even in size. We compared the morphologic features of the Paneth cell-containing small intestinal adenocarcinomas (Group I) with those without Paneth cells (Group II). Group I was distinguished from Group II by its better differentiation, larger tumor size and lower incidence of calcification. Although Paneth cells are extremely rare in human gastrointestinal carcinomas, twenty percent of MNNG-induced intestinal carcinomas harbor Paneth cells. The neoplastic Paneth cells in experimental carcinomas may differentiate from uncommitted cells in the deeper portion of the crypt.

Adenocarcinoma↗
PubMed1990

Endoscopic injection sclerotherapy in patients with bleeding esophageal varices: a retrospective analysis.

Endoscopic injection sclerotherapy has been accepted as the procedure of choice for patients with variceal hemorrhage. To evaluate the efficiency of endoscopic injection sclerotherapy in patients with bleeding esophageal varices, we did a retrospective study of 52 patients (non-sclerotherapy group) with bleeding esophageal varices who were admitted to hospitals and did not receive sclerotherapy and of 50 patients (sclerotherapy group) who received sclerotherapy with ethanolamine oleate. The mortality (sclerotherapy group vs. non-sclerotherapy group: 18.0% vs. 32.7%) during index hospitalization, the bleeding risk factor (the number of rebleeds per patient/month; 1.56 +/- 2.76 vs. 4.96 +/- 9.99: mean +/- SEM) and the mortality due to bleeding (14.0% vs. 36.5%) were higher in the non-sclerotherapy group than in the sclerotherapy group. Only those in Child's class C who received sclerotherapy had a significantly better survival rate than the non-sclerotherapy group (p less than 0.05). Although formal comparisons were not made because of the retrospective nature of this study, endoscopic injection sclerotherapy is effective and appears to be superior to conventional medical treatments.

Adult↗
PubMed1989

Stage dependent expression of inhibin alpha and beta-B subunits during the cycle of the rat seminiferous epithelium.

In order to elucidate the putative role of inhibin in regulation of spermatogenesis, expression of inhibin subunits was examined at defined stages of the cycle of the rat seminiferous epithelium. Twenty 2-mm segments of seminiferous tubules at stages XIII-I, II-VI, VII-VIII, and IX-XII were dissected using the transillumination technique and subunit specific messenger RNAs (mRNAs) were quantitated by filter hybridization. The alpha and beta-B subunit mRNAs varied significantly in different stages, the highest levels of both alpha and beta-B subunit expression were seen in stages XIII-I and the lowest in stages VII-VIII. The hybridization signals obtained with beta-actin probe were not significantly different between different stages indicating that the differences in the quantities of subunit mRNAs in different stages were not due to different amounts of RNA blotted. beta-A subunit mRNA levels were below the detection limit of the filter hybridization method. These data demonstrate that expression of inhibin alpha and beta-B subunits in the rat testis is stage dependent and suggest a paracrine role for inhibin-related peptides in regulation of spermatogenesis.

Animals↗
PubMed1989

Regulation of testicular inhibin subunit messenger ribonucleic acid levels in vivo: effects of hypophysectomy and selective follicle-stimulating hormone replacement.

To examine the pretranslational regulation of inhibin subunits in the rat testis by FSH, we studied the effects of hypophysectomy with or without selective FSH replacement on testicular inhibin subunit mRNA levels in immature and adult animals. In the first experiment (Exp I), sexually immature (20-23 days old) intact and hypophysectomized male rats were killed 1, 3, and 7 days after surgery, and the testicular content of inhibin subunit mRNAs was determined by filter hybridization. A second group of immature, intact, or hypophysectomized rats was treated with saline or FSH for 7 days as follows: I) intact, saline; II) hypophysectomized, saline; III) hypophysectomized, FSH [0.05 microgram/100 g BW, sc, twice daily (BID)]; IV) hypophysectomized, FSH (0.50 microgram/100 g BW, sc, BID); V) hypophysectomized, FSH (5.0 micrograms/100 g BW, sc, BID); and VI) hypophysectomized, FSH (50.0 micrograms/100 g BW, sc, BID). In the second experiment (Exp II), adult (60 days old) intact or hypophysectomized animals were treated with saline, FSH, and/or testosterone for 7 days as follows: I) intact, saline; II) hypophysectomized; saline; III) hypophysectomized, 22-mm testosterone implant; IV) hypophysectomized, FSH (50.0 micrograms/100 g BW, sc, BID; and V) hypophysectomized, 22-mm testosterone implant plus FSH (50.0 micrograms/100 g BW, sc, BID. The effects of FSH and testosterone on testicular inhibin subunit mRNA levels were measured by filter hybridization. In Exp I, the level of inhibin alpha-subunit mRNA per testis was significantly lower in hypophysectomized rats than in intact controls at all time points after surgery. Replacement of FSH to hypophysectomized immature rats led to a dose-dependent increase in alpha-subunit mRNA per testis. However, hypophysectomy and FSH replacement had no significant effect on beta-B-subunit mRNA. In adult rats (Exp II), hypophysectomy significantly lowered and FSH replacement increased testicular inhibin alpha-subunit mRNA levels. Replacement of testosterone to adult animals, either alone or in combination with FSH, had no effect on expression of inhibin alpha-subunit mRNA. beta-B mRNA levels in adult testis were not significantly altered by any of the treatments. beta-A-Subunit mRNA levels were below the detection threshold of filter hybridization in both Exp I and II. Collectively, these data demonstrate that FSH regulates alpha- but not beta-B-subunit mRNA in the testis of both immature and adult rats in vivo. Differential regulation of inhibin subunits may provide a mechanism for creation and regulation of functional diversity of inhibin-related peptides in the testis.

Animals↗
PubMed1989

[Development of Eimeria tenella in MDBK cell culture with a note on enhancing effect of preincubation with chicken spleen cells].

Eimeria tenella, an intracellular protozoan parasite infecting the epithelial cells of the ceca of chickens, causes severe diarrhea and bleeding that can lead its host to death. It is of interest that E. tenella first penetrate into the mucosal intraepithelial lymphocytes (IEL) before they parasitize crypt or villous epithelial cells. This in vitro study was undertaken to know whether the penetration of E. tenella into such a lymphoid cell is a beneficial step for the parasite survival and development. Three sequential experiments were performed. First, the in vitro established bovine kidney cell line, MDBK cells, were evaluated for use as host cells for E. tenella, through morphological observation. Second, the degree of parasite development and multiplication in MDBK cells was quantitatively assayed using radioisotope-labelled uracil (3H-uracil). Third, the E. tenella sporozoites viability was assayed after preincubation of them with chicken spleen cells. E. tenella oöcysts obtained from the ceca of the infected chickens were used for the source of the sporozoites. Spleen cells (E) obtained from normal chickens (FP strain) were preincubated with the sporozoites (T) at the E:T ratio of 100:1, 50:1 or 25:1 for 4 or 12 hours, and then the mixture was inoculated into the MDBK cell monolayer. Morphologically the infected MDBK cells revealed active schizogonic cycle of E. tenella in 3-4 days, which was characterized by the appearance of trophozoites, and immature and mature schizonts containing merozoites. The 3H-uracil uptake by E. tenella increased gradually in the MDBK cells, which made a plateau after 48-60 hours, and decreased thereafter. The uptake amount of 3H-uracil depended not only upon the inoculum size of the sporozoites but also on the degree of time delay (preincubation; sporozoites only) from excystation to inoculation into MDBK cells. The 3H-uracil uptake became lower as the preincubation time was prolonged. In comparison, after preincubation of sporozoites with spleen cells for 4 or 12 hours, the 3H-uracil uptake was significantly increased compared with that of control group. From the results, it was inferred that, although the penetration of E. tenella sporozoites into the lymphoid cells such as IEL is not an essential step, it should be at least a beneficial one for the survival and development of sporozoites in the chicken intestine.

Animals↗
PubMed1988

Inflammatory fibroid polyps of gastrointestinal tract. Evolution of histologic patterns.

Fifteen cases of inflammatory fibroid polyps (IFPs) of the gastrointestinal tract were subjected to histopathologic analysis. Six of them were from the small intestines and the remainder from the stomach. Their size ranged from 0.2 to 12.0 cm in maximum cross-section. The polyps were classified into four groups, based on histology and size. The nodular stage (average: 0.4 cm) showed nodules of immature fibroblasts with a loose myxoid background resembling a tactile corpuscle of Meissner. The fibrovascular stage (average: 1.5 cm) demonstrated concentric aggregations of mature fibroblasts, with endothelial proliferation and eosinophilic infiltration. When the polyps became larger (average: 4.8 cm), the histologic patterns were modified, evolving into the sclerotic or edematous stage by either collagenization or vascular compromise following intestinal obstruction. This study suggests that histologic patterns of IFPs may represent an evolutional change when size is increased.

Adult↗
PubMed1988

Regulation of alpha and luteinizing hormone beta subunit messenger ribonucleic acids during stimulatory and downregulatory phases of gonadotropin-releasing hormone action.

Decreased gonadotropin responsiveness (downregulation) to gonadotropin-releasing hormone (GnRH) following chronic in vivo and in vitro exposure to GnRH or its agonist (GnRH-A) has been previously reported. In the present studies, changes in LH subunit mRNAs in rat pituitary monolayer culture during stimulatory and down regulatory phases of GnRH action are described. Rat pituitary cells in culture, pretreated with medium alone or GnRH-A (10(-6) M) for 48 h were extensively washed and treated with graded concentrations of GnRH [10(-9) to 10(-7)] for 4 h. Medium was assayed for luteinizing hormone (LH) immunoreactivity, and total cytoplasmic RNAs were extracted by the hot phenol-guanidinium isothiocyanate method. Subunit-specific mRNAs were quantified by dot-hybridization assay using 32P-labeled subunit-specific cDNA probes. Cells pretreated with medium alone showed a dose-dependent increase in medium LH immunoreactivity, but the alpha and LH beta mRNAs showed no change over the 4-h period. Cells pretreated with GnRH-A showed no significant increase in medium LH with GnRH treatment, thus demonstrating that the cells had been desensitized by prior GnRH-A treatment. Alpha and LH beta subunit mRNAs of cells pretreated with GnRH-A did not show any significant change with further GnRH treatment. In subsequent experiments, cells were incubated with medium alone or 10(-7) M GnRH for 4, 8, or 24 h. GnRH failed to increase subunit mRNAs after 4 and 8 h incubation; after 24 h, alpha subunit mRNA showed a modest but significant increase and beta subunit mRNA showed a modest decrease compared to controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Peripheral cholangiocarcinoma and clonorchiasis: CT findings.

Sixteen patients with peripheral cholangiocarcinoma of the liver were examined with computed tomography (CT). None of the 16 patients presented with jaundice or had documented cirrhosis. On scans obtained both before and after the injection of contrast material, the tumors were depicted as low-attenuation masses in all cases, with wide variations in homogeneity. The tumor margin was irregular in 12 cases, and there was minimal contrast enhancement of the tumor in 14 cases. In 11 (69%) patients, CT demonstrated masses of markedly low attenuation, which corresponded to areas of diffuse microcystic change seen at histologic examination of resected specimens. In ten (63%) patients, the results of stool or intradermal tests for Clonorchis sinensis were positive. In all ten cases of clonorchiasis, mild, diffuse dilatation of the intrahepatic bile ducts was seen in addition to the low-attenuation masses, but there was no dilatation of the extrahepatic biliary tree. In five of the ten patients with clonorchiasis, stippled or aggregated, powderlike areas of high attenuation were seen on precontrast CT scans; at pathologic examination, those areas were found to be mucin. Extrahepatic metastases were demonstrated in ten (63%) patients. Peripheral cholangiocarcinoma should be the primary diagnostic consideration when these characteristic CT findings are detected in a noncirrhotic patient.

Adenoma, Bile Duct↗
PubMed1988

Regulation of alpha and rat luteinizing hormone-beta messenger ribonucleic acids during gonadotropin-releasing hormone agonist treatment in vivo in the male rat.

Agonist analogs of GnRH, after an initial period of stimulation, down-regulate gonadotropin secretion in both man and experimental animals. To study the pretranslational changes in LH subunits during GnRH agonist (GnRH-A) treatment in vivo, 55-day-old male Wistar rats were divided into two groups as follows: 1) sham operated, and 2) testosterone (T)-replaced castrated animals. T replacement was given by 20-mm T implants. Each group was subdivided into two subgroups to receive either saline or 1 microgram GnRH-A (D-Leu6,Des,Gly10-GnRH Net) by daily sc injection. Pituitaries were harvested after 1, 7, and 28 days of GnRH-A treatment for measurements of LH subunit mRNAs by dot hybridization assay. Serum LH concentrations were measured by a RIA. In intact animals, serum LH concentrations, measured 24 h after the GnRH-A injection, were higher in the GnRH-A group than in saline controls on day 1, but not on days 7 and 28. However, alpha and LH beta mRNA levels were higher in the GnRH-A-treated animals than in saline controls only on day 28, but not on days 1 and 7, however, in T-replaced castrated rats, in which testicular feedback to the pituitary was clamped by orchiectomy and replacement with a fixed dose of exogenous T, GnRH-A decreased serum LH and LH beta mRNA levels compared to those in saline controls. alpha mRNA levels were, however, not different between GnRH-A- and saline-treated animals at any time. We conclude that 1) an early increase in serum LH after 1 day of GnRH-A treatment probably reflects the release of preformed LH rather than increased synthesis; 2) in T-replaced castrated animals where the testicular feedback is clamped, GnRH-A-induced down-regulation of LH can be explained by a decrease in LH beta mRNA; and 3) differences in the LH subunit responses of intact and T-replaced castrated animals provide further evidence for testicular modulation of the LH response to GnRH-A.

Animals↗
PubMed1987

The effect of verapamil on cysteamine-induced duodenal ulcer in the rat.

To determine the effect of verapamil on experimental duodenal ulcer, pathologic assessment and secretory study were performed in the rats with ulcerogenic dose of cysteamine. The cysteamine increased gastric acid secretion and produced double duodenal ulcers at the proximal protion of the duodenum. Intramuscular injection of verapamil, 3 hours later, produced a significant decreased in gastric acid secretion which lasted at least 4 hours (cysteamine vs. cysteamine+ verapamil; 63.5 +/- 18.4 muEq vs. 25.5 +/- 9.0 muEq during the 1st hour after verapamil administration, 83.1 +/- 24.2 muEq vs. 27.8 +/- 12.3 muEq during the 2nd hour, 110.9 +/- 14.4 muEq vs. 38.5 +/- 25.9 muEq during the 3rd hour, 116.4 +/- 12.1 muEq vs. 40.7 +/- 29.6 muEq during the 4th hour, p less than 0.001). However, cysteamine-induced duodenal ulcers were not alleviated by two doses of intramuscular verapamil administration (4 mg/kg x 2). It is presumed that suppression of gastric acid secretion may not be sufficient to reduce cysteamine-induced duodenal ulcer formation or that verapamil itself may have aggresive effects against duodenum. To illucidate the exact role of verapamil in cysteamine-induced duodenal ulcer, further studies would be needed.

Animals↗