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Biomedical subjects

T H Kim

Publications and source records attributed to T H Kim.

At least 163 records · Page 9Linked to original sources

Anti-angiogenic activity of ursodeoxycholic acid and its derivatives.

Ursodeoxycholic acid (UDCA) and its derivatives were examined for anti-angiogenic activities by using the chick embryo chorioallantoic membrane (CAM) assay. The presence of UDCA or its derivatives inhibited angiogenesis in a dose-dependent manner; the dose required for half-maximal inhibition (ID50) was 4 microg per CAM for UDCA. The conjugate forms of UDCA with glycine methyl ester (HS-1030), L-leucine benzyl ester (HS-1068) and L-leucine methyl ester (HS-1133) were showing ID50 of 0.09, 0.08 and 0.6 microg per CAM, respectively. Also, the effect of UDCA and its derivatives on the viability of calf pulmonary artery endothelial (CPAE) cells was examined. Among them, HS-1030 effectively reduced the viability of CPAE cells in a concentration-dependent manner. Based on these results, we speculated that HS-1030 might be a promising candidate as angiogenesis inhibitor for use in the management of diseases accompanied by uncontrolled angiogenesis including solid tumor.

Animals↗

Extracellular matrix remodeling at the early stages of liver regeneration in the rat.

Previous studies have shown that activity of urokinase-type plasminogen activator (u-PA) increases very rapidly (within 1 minute) after partial hepatectomy. In view of the well-recognized roles of u-PA as one of the major initiators of the matrix proteolysis cascade and as an activator of plasminogen and hepatocyte growth factor (HGF), we studied matrix degradation in liver shortly after partial hepatectomy. The activation of plasminogen to plasmin following partial hepatectomy was examined by Western blot analysis, and a small increase in plasmin at approximately 15 minutes followed by a large elevation at approximately 3 to 6 hours after partial hepatectomy was detected. In addition, we found that fibrinogen, the major substrate for plasmin, begins to be degraded at approximately 15 to 30 minutes following partial hepatectomy. Using immunohistochemical staining, we detected that the distribution of fibrinogen in normal liver is localized to the perisinusoidal space surrounding the periportal region. A decreased distribution of fibrinogen in the periportal region was found by 15 minutes and continued through 24 hours following partial hepatectomy. In addition, the distribution of fibronectin in normal liver was localized to the perisinusoidal space surrounding the periportal and the pericentral regions. A strikingly decreased distribution of fibronectin in the periportal region was found at 5 minutes after partial hepatectomy. Furthermore, we observed that the protein levels of laminin, entactin, and fibronectin in an extracellular matrix (ECM)-enriched preparation decreased shortly after partial hepatectomy, and were restored later. No changes were observed with either vitronectin or the integrin chain alpha(v). In contrast to the protein levels of the ECM components, the messenger RNA (mRNA) levels of fibronectin, integrin chain beta1, and integrin chain alpha(v) gradually increased over 18 hours and then decreased thereafter. Taken together, these results suggest that rapid reorganization of selected ECM components are important for hepatocyte proliferation at the early stages of liver regeneration.

Animals↗

Pseudo-Kaposi's sarcoma associated with acquired arteriovenous fistula.

Pseudo-Kaposi's sarcoma or acroangiodermatitis usually has underlying conditions of increased venous pressure or circulatory abnormality. We experienced two cases of pseudo-Kaposi's sarcoma in patients with acquired iatrogenic arteriovenous fistula from hemodialysis on their forearms. The patients complained of painful swollen crusted vesicles and purple or erythematous patches or plaques on their hands and fingers. Histologic findings included features of pseudo-Kaposi's sarcoma such as proliferations of small vascular spaces with narrow vascular channels lined by spindle cells, extravasated erythrocytes, and hemosiderin deposits. Percutaneous arteriography performed in Case one excluded the possible coexistence of arteriovenous malformation. In both cases, venous pressure and skin surface temperature were increased around the lesions; these may have played important roles in the development of the lesions. Both cases improved after oral erythromycin treatment, which seemed to be safe and effective for pseudo-Kaposi's sarcoma.

Acrodermatitis↗

A case of estrogen dermatitis.

A 29-year-old Korean woman had erythematous papular patches on her face for six months. The eruptions recurred in a cyclic fashion along with her menstruation. The patient responded positively to an intradermal skin test for estrogen and showed marked improvement with the antiestrogen drug, Tamoxifen. We concluded that sensitivity to her own estrogen caused this dermatitis, that an intradermal skin test with progesterone and estrogen should be carried out routinely in patients with cyclic premenstrual flares, and that tamoxifen can be used as a specific therapy. To the best of our knowledge, this woman is the first patient with estrogen dermatitis reported in Korea.

Adult↗

Benign and malignant esophageal strictures: treatment with a polyurethane-covered retrievable expandable metallic stent.

PURPOSE: To evaluate the clinical effectiveness of a polyurethane-covered, retrievable, self-expandable metallic stent and hook catheter in the treatment of esophageal strictures. MATERIALS AND METHODS: Stents were constructed of 0.4-mm stainless steel wire in a cylindric zig-zag configuration of six to nine bends. Four to eight stents were connected in tandem by dipping in a polyurethane solution. A nylon loop was hooked inside to each bend of the proximal portion of the stent and strung with a thread. Under fluoroscopic guidance, 22 stents were placed in 16 patients with a malignant stricture and five patients with a benign stricture. The stent was removed with a hook catheter 2 months after placement in patients with a benign stricture and when complications occurred in patients with a malignant stricture. All patients had dysphagia with ingestion of soft foods or liquids. RESULTS: Stent placement was technically successful and well tolerated in 20 patients. In one patient, the stent was misplaced but relocated successfully. After stent placement, all patients were able to ingest solid and/or soft foods without dysphagia. After stent removal, strictures showed improvement but recurred in two patients. CONCLUSION: Use of polyurethane-covered, retrievable expandable stents seems to be a feasible and effective method of treatment of benign and malignant esophageal strictures.

Adolescent↗

[Bacterial endosymbiosis within the cytoplasm of Acanthamoeba lugdunensis isolated from a contact lens storage case].

Transmission electron microscopy of an Acanthamoeba isolate (KA/L5) from a contact lens case revealed bacterial endosymbionts within cytoplasm of the amoebae. The Acanthamoeba isolate belonged to the morphological group II. Based on the polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) of 18S ribosomal RNA coding DNA (rDNA), the isolate was identified as A. lugdunensis. Strain typing by isoenzyme analysis using isoelectric focusing (IEF) and mitochondrial (Mt) DNA RFLP revealed that the isolate was closely related with KA/L1, the most predominant type of isolates from contact lens storage cases, KA/E2, a clinical isolate, KA/W4, previously reported to host endosymbionts, and L3a strains of A. lugdunensis. The endosymbionts were similar to those of KA/W4 in aspects that they were randomly distributed in both trophozoites and cysts, and were rod-shaped bacteria measuring approximately 1.38 x 0.50 microns. But the number of endosymbionts per amoeba was significantly lower than that of KA/W4. They were neither limited by phagosomal membranes nor included in lacunaelike structure.

Acanthamoeba↗

Presence of urokinase in serum-free primary rat hepatocyte cultures and its role in activating hepatocyte growth factor.

Serum-free rat hepatocyte cultures can be stimulated to divide by the inactive, single-chain form of hepatocyte growth factor (scHGF), suggesting that hepatocytes contain a protein that can cleave scHGF to its biologically active, two-chain (tcHGF) form. We added radiolabeled scHGF to serum-free cultures and confirmed that tcHGF was being generated. Because scHGF can be cleaved to tcHGF by plasminogen activators (PAs), we next tested the cultures for active PA. Although little PA activity was initially present, the majority was of the urokinase type (u-PA) as determined by neutralization studies using either a polyclonal antibody against u-PA or, since u-PA functions in the context of its receptor (u-PAR), a monoclonal antibody against u-PAR. Considerable PA activity developed within 24 h, which was also neutralizable with antibody. To test whether the active, receptor-bound u-PA from the cell cultures was cleaving scHGF, iodinated scHGF was added to intact cells in the presence of the antibody against u-PAR. Comparison to control cultures determined that the antibody prevented scHGF cleavage. Analysis of cultures treated with HGF, epidermal growth factor, and transforming growth factor alpha (TGF-alpha) alpha showed these growth factors increased the hepatocyte PA activity in parallel with the mRNA for u-PA. TGF-beta had the opposite effect, and when TGF-beta was added to the culture system, conversion of scHGF to tcHGF was prevented in concert with the production of the type 1 PA inhibitor. When liver remnants from hepatectomized animals were assayed for active TGF-beta, elevated protein was found just prior to the appearance of PA inhibitor 1 message and protein. Collectively, our data show that in culture, active u-PA is present and cleaves scHGF to tcHGF in the context of its receptor. It also suggests that modulation of u-PA activity by various growth factors is relevant for regulating cleavage of scHGF to tcHGF both in vitro and in vivo.

Animals↗

Protective effect of ginseng on radiation-induced DNA double strand breaks and repair in murine lymphocytes.

We have examined the effects of ginseng on the induction and repair of gamma-ray-induced DNA double strand breaks (dsb) using neutral filter elution technique at pH 9.6 in cultured murine spleen lymphocytes. Ginseng water extract 500 micrograms/ml was added to the culture medium either for 48 hours prior to irradiation. Ginseng extract showed protective effect against the formation of dsb when it was treated for 48 hours before 100 Gy gamma-ray-irradiation. While repair was almost completed until 220.2 minutes after irradiation, DNA repair of irradiated cells in the presence of ginseng extract was did not return to the corresponding control levels even after 621.8 minutes. From these data, it could be calculated that ginseng reduced the relative strand scission factor (RSSF) by about 2. Therefore, it could be concluded that ginseng has radioprotective effect against gamma-ray induced DNA dsb and repair in cultured mouse lymphocytes.

Animals↗

Two cases of pachydermodactyly.

We report two cases of pachydermodactyly. Case 1 was a 16-year-old girl who complained of asymptomatic, bulbous, firm swellings which developed insidiously on both sides of the proximal interphalangeal (PIP) joint of her right middle finger. Case 2 was a 14-year-old boy with similar lesions on the sides of the PIP joints of the index and middle fingers of both hands. They both had histories of mild, repetitive mechanical trauma of the fingers. Radiologic findings showed soft tissue swellings without any bony or articular abnormalities. Histopathologic findings from the bulbous swellings revealed marked hyperkeratosis, slight epidermal hyperplasia, and a markedly thickened dermis with a deposition of mucinous material among the collagen fibers. Ultrastructural examinations of both cases showed decreased diameters of collagen fibrils. The lesions temporarily improved with intralesional injection of triamcinolone acetonide. Pachydermodactyly is more commonly found in boys and the affected fingers are more numerous in boys. Both of the present cases had the habit of rubbing and gripping their fingers unconsciously. Mechanical trauma of the fingers around puberty may play an important role in pachydermodactyly.

Adolescent↗

Appendicitis: usefulness of color Doppler US.

PURPOSE: To assess whether color Doppler ultrasonography (US) can help diagnose early acute appendicitis in appendices of equivocal size at gray-scale US. MATERIALS AND METHODS: In a retrospective study, color Doppler US findings were evaluated in 20 individuals with proved normal appendix at barium enema examination and in 50 patients in whom pathologic findings confirmed acute appendicitis. In a prospective study, the diagnostic value of hyperemia in the wall of the appendix in differentiating a normal from an inflamed appendix was evaluated in 26 patients with appendices of equivocal size (5-7 mm in maximal outer diameter) at grayscale US. RESULTS: In the retrospective study, 44 of the 50 patients had hyperemia at color Doppler US. The remaining six patients had no hyperemia, and pathologic findings confirmed gangrenous appendices. The 20 patients with proved normal appendix at barium enema examination had no detectable blood flow in the wall. In the prospective study, 10 of 26 patients had hyperemia at color Doppler US, and pathologic findings confirmed early acute appendicitis. Results of barium enema examination (n = 12) or clinical follow-up (n = 4) confirmed no appendicitis in the remaining 16 patients. CONCLUSION: Hyperemia in the wall of the appendix at color Doppler US is a sensitive indicator for inflammation. A simple additional color Doppler US examination may be helpful in the diagnosis of early acute appendicitis when an appendix is well depicted and is equivocal in size at gray-scale US.

Acute Disease↗

A case of bleomycin-induced scleroderma.

The association of exposure to bleomycin with the development of scleroderma-like cutaneous abnormalities has been reported. We experienced a case of scleroderma involving the hands, feet, and forearms after bleomycin chemotherapy. The present report supports the possible causal relation of bleomycin with scleroderma. Regarding the widespread use of bleomycin, this complication is thought to be under appreciated.

Bleomycin↗

Two cases of mequitazine-induced photosensitivity reactions.

Mequitazine is a phenothiazine derivative antihistamine. We experienced 2 cases of mequitazine-induced photosensitivity reaction in patients who took mequitazine for their dermatologic problems. Case no. 1 showed features of photoallergy such as 1-month incubation period, decreased MED to UVA, strong positive photopatch test result, cross reaction to chlorpromazine, and angry back phenomenon found in allergic contact dermatitis. In addition, an immediate erythematous macule was observed on the photopatch test site of mequitazine directly after UV exposure which was similar to the immediate erythema noted in chlorpromazine photoallergy. During the follow-up period of two months, there was transiently decreased MED to UVB, which became normalized after 1 month treatment with cyclophosphamide. In case no. 2, the pathogenic mechanism seemed to be persistent light reaction preceded by systemic photoallergy, as he had taken mequitazine for 6 months, and there were strong positive photopatch test results with immediate erythema reaction, cross-reaction to promethazine, decreased MED to both UVA and UVB, and persistence of the photosensitivity over a 3-year follow-up period after discontinuation of the mequitazine. Photopatch tests to 1% mequitazine with 5 J/cm2 of UVA in 30 normal subjects were all negative, which means that 1% concentration may be appropriate for the photopatch test. Mequitazine seemed to play a part similar to chlorpromazine, and absence of mequitazine-induced photosensitivity may be due to a relatively low dosage of the drug. However, dermatologists should be cautious about a photosensitivity reaction induced by mequitazine or other phenothiazine-derivative drugs.

Chlorpromazine↗

Nonsurgical placement of a nasolacrimal polyurethane stent.

PURPOSE: To describe the placement of a nasolacrimal polyurethane stent with a new introducer set and hook. MATERIALS AND METHODS: The authors designed a soft polyurethane stent, an introducer that does not require balloon dilation, and a hook that can remove a ball-tipped guide wire from the inferior nasal meatus under fluoroscopic guidance. The stent was placed in 51 lacrimal systems in 44 outpatients who had complete obstruction of the lacrimal sac or nasolacrimal duct. RESULTS: Stent placement was technically successful and well tolerated in 50 of 51 nasolacrimal systems. The procedure lasted an average of 16 minutes (range, 10-33 minutes). After stent placement, 47 of 50 eyes showed complete resolution of epiphora, and the other three showed partial resolution. During follow-up, no stents migrated, and one stent became blocked. The stent was reopened by means of forceful irrigation of saline solution through the superior punctum. CONCLUSION: Placing a polyurethane nasolacrimal stent by use of the new introducer and hook simplifies the technique, shortens operating time, reduces cost, and makes the procedure well tolerated by patients.

Adolescent↗

Profound hypotension immediately following insertion of methyl methacrylate during bipolar endoprosthesis in a patient with long-term levodopa-treated paralysis agitans.

Insertion of methyl methacrylate polymer into newly reamed bony cavities has sometimes resulted in profound hypotension, cardiac arrest, or sudden death which are more common in patients with hemodynamic instability or hypovolemia. In paralysis agitans(Parkinson's disease), dramatic worsening of the disease often occurs when another illness or trauma accompanies it. And it is possible that chronic medication with levodopa can cause the loss of ability to support blood pressure. So, it involves some risk to use methyl methacrylate in chronic levodopa-treated paralysis agitans. We present a case of paralysis agitans who demonstrated profound hypotension immediately following insertion of methyl methacrylate polymer in spite of normovolemia and proper anesthetic management.

Aged↗

The first human case of Diplogonoporus balaenopterae (Cestoda: Diphyllobothriidae) infection in Korea.

The first human case of Diplogonoporus balaenopterae infection is reported in Korea. The patient was a 41-year old male who passed a part of cestode strobila, about 1 m long, spontaneously in his stool. He used to eat raw marine fish when he drank alcohol. The worm was identified as D. balaenopterae after morhological observations and literature review. Results of laboratory examination were within normal limits except for slight eosinophilia (6%) and extraordinarily high serum Ig E level (10,182 IU/ml).

Adult↗