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S H Huh

Publications and source records attributed to S H Huh.

17 recordsLinked to original sources
PubMed2003

Advanced management of venous malformation with ethanol sclerotherapy: mid-term results.

PURPOSE: This paper is an update of previously published data on the basis of a retrospective review of midterm results of ethanol sclerotherapy on 87 patients (January 1995 to December 2000) for assessment of its efficacy as an improved treatment method for venous malformation (VM). According to this assessment, VMs were defined with a new classification and studied with advanced diagnostic technology and an advanced care system. METHODS: The average follow-up period was 24 months after completion of a multisession treatment (mean, 8.2 months). Classification of VM was based on a modification of the Hamburg classification. Advanced diagnostic technology, mostly noninvasive, was used on 226 of 520 patients with congenital vascular malformation registered at the Congenital Vascular Malformation Clinic at the Samsung Medical Center. Of the 226 patients with VM, 87 with infiltrating extratruncular lesions had a total of 399 sessions of sclerotherapy. Follow-up assessment with periodic clinical examinations by the multidisciplinary team was supplemented with body blood pool scans, duplex scans, and magnetic resonance imaging, according to protocol, once the multisession therapy was completed. Angiographic assessment was seldom included. The endpoint of this phase II study was 24 months. RESULTS: Of 399 sessions, initial success was seen in 379 sessions (95.0%) and failure was seen in 20 sessions (5%). This was mostly caused by forced abandonment from technical difficulty in delivering ethanol safely to the lesion (eg, direct drainage of VM into normal deep vein system). Later results after completion of the multisession therapy with a minimum follow-up of 24 months on 71 VMs have shown no evidence of recurrence. Eighty-seven patients have shown the same results without recurrence on an average of 18.2 months of follow-up. Fifty-one minor to major complications, mostly skin damage, developed after 47 sessions among the 379 sessions (12.4% in 24/87 patients; 27.9%). However, complications resolved spontaneously or were managed successfully, except for one permanent facial nerve palsy and one peroneal nerve palsy. CONCLUSION: Absolute ethanol sclerotherapy can deliver excellent results as an independent therapy to the infiltrating type of extratruncular form of VM, which was once taboo because of prohibitively high morbidity. Absolute ethanol may be accepted as an effective treatment method because no recurrence has been observed in the relatively long-term observation period and the morbidity has been acceptable. However, it should be reserved only for individuals and centers with expertise. The morbidity involved should be clearly understood and accepted by the patient or family, and the risk of acute and chronic complications, both major or minor, should be explained to the patient. Long-term assessment of the complication's sequelae is warranted.

Adolescent↗
PubMed2001

Negative regulation of the SAPK/JNK signaling pathway by presenilin 1.

Presenilin 1 (PS1) plays a pivotal role in Notch signaling and the intracellular metabolism of the amyloid beta-protein. To understand intracellular signaling events downstream of PS1, we investigated in this study the action of PS1 on mitogen-activated protein kinase pathways. Overexpressed PS1 suppressed the stress-induced stimulation of stress-activated protein kinase (SAPK)/c-Jun NH(2)-terminal kinase (JNK) in human embryonic kidney 293 cells. Interestingly, two functionally inactive PS1 mutants, PS1(D257A) and PS1(D385A), failed to inhibit UV-stimulated SAPK/JNK. Furthermore, H(2)O(2-) or UV-stimulated SAPK activity was higher in mouse embryonic fibroblast (MEF) cells from PS1-null mice than in MEF cells from PS(+/+) mice. MEF(PS1(-/-)) cells were more sensitive to the H(2)O(2)-induced apoptosis than MEF(PS1(+/+)) cells. Ectopic expression of PS1 in MEF(PS1(-/-)) cells suppressed H(2)O(2)-stimulated SAPK/JNK activity and apoptotic cell death. Together, our data suggest that PS1 inhibits the stress-activated signaling by suppressing the SAPK/JNK pathway.

Animals↗
PubMed2001

Hsp72 functions as a natural inhibitory protein of c-Jun N-terminal kinase.

Hsp72, a major inducible member of the heat shock protein family, can protect cells against many cellular stresses including heat shock. In our present study, we observed that pretreatment of NIH 3T3 cells with mild heat shock (43 degrees C for 20 min) suppressed UV-stimulated c-Jun N-terminal kinase 1 (JNK1) activity. Constitutively overexpressed Hsp72 also inhibited JNK1 activation in NIH 3T3 cells, whereas it did not affect either SEK1 or MEKK1 activity. Both in vitro binding and kinase studies indicated that Hsp72 bound to JNK1 and that the peptide binding domain of Hsp72 was important to the binding and inhibition of JNK1. In vivo binding between endogenous Hsp72 and JNK1 in NIH 3T3 cells was confirmed by co-immunoprecipitation. Hsp72 also inhibited JNK-dependent apoptosis. Hsp72 antisense oligonucleotides blocked Hsp72 production in NIH 3T3 cells in response to mild heat shock and concomitantly abolished the suppressive effect of mild heat shock on UV-induced JNK activation and apoptosis. Collectively, our data suggest strongly that Hsp72 can modulate stress-activated signaling by directly inhibiting JNK.

3T3 Cells↗
PubMed2000

Nitric oxide negatively regulates c-Jun N-terminal kinase/stress-activated protein kinase by means of S-nitrosylation.

NO, produced from l-arginine in a reaction catalyzed by NO synthase, is an endogenous free radical with multiple functions in mammalian cells. Here, we demonstrate that endogenously produced NO can suppress c-Jun N-terminal kinase (JNK) activation in intact cells. Treatment of BV-2 murine microglial cells with IFN-gamma induced endogenous NO production, concomitantly suppressing JNK1 activation. Similarly, IFN-gamma induced suppression of JNK1 activation in RAW264.7 murine macrophage cells and rat alveolar macrophages. The IFN-gamma-induced suppression of JNK1 activation in BV-2, RAW264.7, or rat alveolar macrophage cells was completely prevented by N(G)-nitro-l-arginine, a NO synthase inhibitor. Interestingly, the IFN-gamma-induced suppression of JNK1 activation was not affected by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, an inhibitor of guanylyl cyclase. 8-Bromo-cGMP, a membrane-permeant analogue of cGMP, did not change JNK1 activation in intact cells either. In contrast, S-nitro-N-acetyl-dl-penicillamine (SNAP), a NO donor, inhibited JNK1 activity in vitro. Furthermore, a thiol reducing agent, DTT, reversed not only the in vitro inhibition of JNK1 activity by SNAP but also the in vivo suppression of JNK1 activity by IFN-gamma. Substitution of serine for cysteine-116 in JNK1 abolished the inhibitory effect of IFN-gamma or SNAP on JNK1 activity in vivo or in vitro, respectively. Moreover, IFN-gamma enhanced endogenous S-nitrosylation of JNK1 in RAW264.7 cells. Collectively, our data suggest that endogenous NO mediates the IFN-gamma-induced suppression of JNK1 activation in macrophage cells by means of a thiol-redox mechanism.

Animals↗
PubMed2000

Selenite negatively regulates caspase-3 through a redox mechanism.

Selenium, an essential biological trace element, exerts its modulatory effects in a variety of cellular events including cell survival and death. In our study we observed that selenite protects HEK293 cells from cell death induced by ultraviolet B radiation (UVB). Exposure of HEK293 cells to UVB radiation resulted in the activation of caspase-3-like protease activity, and pretreatment of the cells with z-DEVD-fmk (N-benzyloxycarbonyl-Asp-Glu-Val-Asp-fluoromethylketone), a caspase-3 inhibitor, prevented UVB-induced cell death. Interestingly, enzymatic activity of caspase-3-like protease in cell lysates of UVB-exposed cells was repressed in vitro by the presence of selenite. Selenite also inhibited the in vitro activity of purified recombinant caspase-3 in cleaving Ac-DEVD-pNA (N-acetyl-Asp-Glu-Asp-p-nitroanilide) or ICAD(L) (inhibitor of a caspase-activated deoxyribonuclease) and in the induction of DNA fragmentation. The inhibitory action of selenite on a recombinant active caspase-3 could be reversed by sulfhydryl reducing agents, such as dithiothreitol and beta-mercaptoethanol. Furthermore, pretreatment of cells with selenite suppressed the stimulation of the caspase-3-like protease activity in UVB-exposed cells, whereas dithiothreitol and beta-mercaptoethanol reversed this suppression of the enzymatic activity. Taken together, our data suggest that selenite inhibits caspase-3-like protease activity through a redox mechanism and that inhibition of caspase-3-like protease activity may be the mechanism by which selenite exerts its protective effect against UVB-induced cell death.

Caspase 3↗
PubMed1998

Cloning and identification of a phospholipase gene from vibrio mimicus.

The phospholipase gene phl was identified from Vibrio mimicus (ATCC33653) and sequenced. The entire open reading frame (ORF) was composed of 1410 nucleotides and encoding 470 amino acids. The phl was placed upstream of hemolysin gene (vmhA) with opposite direction of transcription. From the BLAST search program, the deduced amino acids sequence showed 74.4% identity with phospholipase gene (lec) from V. cholerae El Tor. The entire ORF of phospholipase gene was amplified by PCR and inserted into an Escherichia coli expression vector, pET22b(+) and introduced E. coli BL21(DE3). SDS-PAGE demonstrated that a protein corresponding to the phospholipase was overexpressed and migrated at a molecular mass of 53 kDa.

Amino Acid Sequence↗
PubMed1998

Solution structures of the melanocyte-stimulating hormones by two-dimensional NMR spectroscopy and dynamical simulated-annealing calculations.

Melanocortins, which are involved in melanocyte pigmentation control and glucocorticoid stimulation, have functional roles in various physiological mechanisms and have been shown to participate in higher cortical functions. Recently, it has also been reported that melanocyte-stimulating hormone (MSH) and melanocortin 4 receptor (MC4R) are the key components of the hypothalamic response to obesity. The solution structures of both melanocyte-stimulating hormone alpha-MSH (Ac-Ser-Tyr-Ser-Met-Glu-His-Phe-Arg-Trp-Gly-Lys-Pro-Val-NH2) and its analog alpha-MSH-ND (Ac-Ahx-Asp-His-DPhe-Arg-Trp-Lys-NH2) (Ahx, 2-aminohexanoic acid) have been determined by two-dimensional NMR spectroscopy and simulated-annealing calculations. The NMR data revealed that alpha-MSH forms a hairpin loop conformation which includes conserved message sequences, whereas alpha-MSH-ND prefers a type I beta-turn comprising residues of Asp2-His3-DPhe4-Arg5. Final simulated-annealing structures of both alpha-MSH-ND and alpha-MSH peptides converged with rmsd of 0.07 nm for alpha-MSH-ND and 0.1 nm for alpha-MSH between backbone atoms, respectively. This result will provide the structural bases of melanocortin functions as well as valuable information for structure-based drug design involving the regulation of obesity and feeding.

Amino Acid Sequence↗
PubMed1997

Nucleotide sequence of the vmhA gene encoding hemolysin from Vibrio mimicus.

The structural gene (vmhA) of hemolysin from Vibrio mimicus (ATCC33653) was cloned and sequenced. The vmhA gene contains an open reading frame consisting of 2232 nucleotides which can code for a protein of 744 amino acids with a predicted molecular mass of 83,059. The similarity of amino acid sequence shows 81.6% identity with Vibrio cholerae El Tor hemolysin.

Amino Acid Sequence↗
PubMed1987

Is preoperative computed tomography necessary in the management of patients treated for carcinoma of the prostate by 125iodine interstitial implantation and bilateral pelvic lymphadenectomy?

We have evaluated the impact of preoperative pelvic computed tomography (PCT) on the management of 145 patients with adenocarcinoma of the prostate. Our preoperative interpretations were correct in 47 (76%) of the 62 cases with PCT. Twenty-six percent of the 62 patients had microscopically positive lymph nodes, and, of this subgroup, only 50% remain disease-free, at risk for 1 to 7 1/2 years. In contrast, 93% of the subgroup with microscopically negative lymph nodes are free of disease. Of the 83 patients who did not have PCT preoperatively, 18 patients (22%) had microscopically positive lymph nodes and 33% are disease-free; 65 patients (78%) had microscopically negative lymph nodes, and 90% are disease-free, followed for 1 1/2 to 9 years. Thus, there is no significant difference in percent nodal positivity, or disease-free survivals, when comparing the PCT and non-PCT groups, subdivided according to nodal status. We believe that preoperative PCT is an important screening tool, and will provide correct pathological correlations in the majority of cases. However, on the basis of the information derived from this study, the preoperative clinical assessment patients fared no differently from the preoperative PCT patients, thus suggesting that PCT may not be indicated routinely, but should be reserved for questionable situations.

Brachytherapy↗
PubMed1987

The impact of palliative irradiation on the management of patients with acquired immune deficiency syndrome.

We have studied the natural history of the acquired immune deficiency syndrome (AIDS), and the part that irradiation plays in the management of this devastating and fatal disease. The radioresponsiveness of the two most common malignancies associated with AIDS, Kaposi's sarcoma (KS) and malignant lymphoma (ML), has been demonstrated. We have documented satisfactory time-dose relationships for the management of multiple manifestations of KS, including cutaneous and deep subcutaneous extremity involvement, visceral lesions, and AIDS-associated lymphadenopathy. A similar time-dose construct has been documented for ML, involving the brain and both central and peripheral lymph nodes. Irradiation can provide good to excellent palliation with only minimal side effects, and will produce a lesser impact on the hematological and immunological systems than chemotherapy. Therefore, we advocate the liberal employment of palliative radiation therapy in patients with AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1984

Intra-operative iodine-125 prostatic implant following bilateral pelvic lymphadenectomy.

Sixty-five patients with prostatic adenocarcinoma Stages B and C were treated with intraoperative Iodine-125 prostatic implantation following bilateral pelvic lymphadenectomy. Pelvic nodal metastases were found in 31% of the patients: 23% (7/31) in clinical Stage B1 disease, 29% (8/28) in clinical Stage B2, and 83% (5/6) in clinical Stage C. All the patients have been followed for a period of 1 1/2 to 6 years. Serial digital rectal examination revealed complete regression of the palpable disease in 15% of the patients at 6 months, 47% at 1 year, and 87% at 2 years. Post-operative complications were also evaluated: 13% of the patients became sexually impotent, 11% had impaired potency after the procedure, and 16% of patients complained of dry ejaculation; and 17% developed scrotal and/or penile swelling, which persisted up to 14 months, but usually subsided within 5 months. Two patients developed local recurrence. Both patients responded to subsequent external radiation therapy of 7000 rad in 11 to 14 weeks with clinical regression of palpable disease.

Adenocarcinoma↗
PubMed1981

Interstitial irradiation of carcinoma of the prostate with 125iodine and simultaneous extraperitoneal pelvic lymphadenectomy in 32 patients: trials, tribulations and possible triumphs.

A series of 32 patients with carcinoma of the prostate who underwent 125iodine interstitial irradiation to the prostate and simultaneous extraperitoneal pelvic lymphadenectomy was reviewed. The patients were segregated into 3 groups: group 1-patients with early localized low grade disease, group 2-patients with advanced localized high grade disease and group 3-patients with early localized high grade disease and those with advanced localized low grade disease. Owing to the high degree of predictability of the absence or presence of pelvic lymph node metastasis in patients in groups 1 and 2 and the morbidity associated with superficial pelvic lymphadenectomy we do not advocate this procedure in these patients. However, we advocate pelvic lymphadenectomy in patients in group 3 because of the unpredictability of lymph node metastasis. Furthermore, our data indicate that 1) the morbidity of the combined procedures is relatively low, with no patients becoming incontinent and only 12.5 per cent becoming impotent, 2) 125iodine interstitial irradiation of the prostate after transurethral prostatectomy is safer in terms of postoperative complications than is radical prostatectomy and 3) while superficial pelvic lymphadenectomy is not an innocuous procedure it generally is safe and, at times, an important diagnostic staging procedure.

Adenocarcinoma↗
PubMed1976

Locally recurrent carcinoma of the breast. Results of radiation therapy.

Local and regional recurrences are frequent problems in breast cancer management. Radiation therapy is effective in producing long term remission. This study evaluates the results of radiation therapy of 215 patients with recurrent disease limited to the chest wall and/or regional lymph node areas. The local results showed complete control in 67% of cases (mean and median durations 32 months and 22 months, respectively), partial control in 24% of cases (mean and median 11 and 8 months, respectively) and no control in the remaining 9%. The radiation dose recommended for the treatment of recurrent mammary carcinoma is 5000 rads in 5 weeks for relatively small lesions. Supplementary local doses of 500-1000 rads in 1 week may be given to bulky lesions as necessary for residual disease. Although local relapse indicates a poor prognosis, it is by no means totally hopeless. Of 215 patients treated 44 (21%) survived 5 years and 10 (5%) survived 10 years following radiation therapy of recurrent disease. There were seven patients, or 3%, who were free of cancer at 5 to 15 years. Radiation therapy was valuable in controlling local lesions, and thus, in improving quality of survival, even in those patients who eventually died of metastatic disease.

Breast Neoplasms↗
PubMedDate not supplied

Current concepts in lymphatic malformation.

A lymphatic malformation (LM) is the most common form of congenital vascular malformation (CVM). The new Hamburg classification of CVM distinguishes the truncular (T) form from the extratruncular (ET) form of LMs. Both are consequences of a developmental arrest at the different stages of lymphangiogenesis as a result of defective genes. The purpose of this review was to evaluate the current management results of both forms of LMs. A retrospective review of the clinical data of 315 patients with a diagnosis of LMs treated between September 1994 and December 2001 was performed. Lymphoscintigraphy was the most frequent diagnostic test. The patients with the ET form were treated with sclerotherapy with OK-432 and/or ethanol. Combinations of CDP (complex decongestive physiotherapy) and/or compressotherapy were used to treat all the T-form patients. In addition, surgery, either reconstructive or ablative, was offered to patients with the T form who failed to respond to the proper CDP. A multidisciplinary team performed the management of LM, and the results were evaluated every 6 months. Among 797 patients with CVM, 315 were confirmed to have LMs, either as the T form (226) or the ET form (89). Another 66 LMs were diagnosed with hemolymphatic malformations (HLM). Most of the ET forms (89/315) were the cystic type (70/89), while the T forms included aplasia and/or an obstruction (204/226). The ET form was most frequent in the head, neck, and thorax (69/89). The T form was located most frequently to the extremities (202/226), mostly to the lower limb (180/202). Two hundred and twenty-six T forms belonged to the various clinical stages: stages I-32, II-104, III-48, IV-18, and an unclear stage-24. The ET form was treated with sclerotherapy using OK-432 (108/120) and absolute ethanol (12/120). Among the 11 patients with the multiple ET form, 7 patients underwent perioperative sclerotherapy with OK-432 and a subsequent surgical excision. The clinical response of the T form at the extremity to CDP was excellent to good in a majority of clinical stages I to II (121/136) but decreased to a good to fair degree in stages III to IV (31/66). The additional surgical therapy, either reconstructive (10/19) or ablative (9/19), provided limited success in improving CDP efficacy, owing mainly to poor compliance. The long-term outcome of the initial success through self-motivated home-maintenance care during the follow-up period of up to 48 months was totally dependent on patient compliance. OK-432 sclerotherapy to 51 ET forms has shown excellent results on 88.9% of the cystic type (40/45) and 50% (3/6) of the cavernous type (minimum follow-up for 24 months). Seventeen ET forms in 7 patients were treated with a preoperative OK-432 sclerotherapy and a subsequent surgical excision, which provided good to excellent results in 14 for a minimum of 24 months. Primary lymphedema, which is the T form of LMs, can be managed safely by a combination of CDP with compressotherapy. Patients with good compliance can benefit from additional surgical therapy, either reconstructive or ablative. The ET form, particularly the cystic type, can be treated with various scleroagents that are preferably less toxic as the primary therapy. A surgical excision with or without perioperative sclerotherapy provides good results for patients with the localized cavernous type of the ET form. A multidisciplinary team approach is essential for the proper care of LM.

Adolescent↗
PubMedDate not supplied

Expression of the c-erb-B2 and p53 protein in gallbladder carcinomas.

Gallbladder carcinoma is the most common malignancy of the biliary tract in Korea and known to be more common in East Asia and Latin America than in Europe and North America. However, their exact histopathological characteristics and carcinogenesis are not well-elucidated. A total of 71 cases of gallbladder carcinomas, two cases of gallbladder dysplasia and 20 cases of gallbladder adenoma were immunohistochemically studied to evaluate the expression of c-erb-B2 and p53 proteins in the light of their relationship with various prognostic factors. Thirty-three gallbladder carcinomas (46.5%) showed positive staining for c-erb-B2, but none of the dysplasia and adenoma were positive (p<0.05). c-erb-B2 was stained in the cell membrane of the cancer cells. Adjacent normal mucosa was negative for c-erb-B2 staining. Forty-eight gallbladder carcinomas (67.6%) showed positive staining in the nucleus for p53 protein. None of the cases with dysplasia, adenoma, and normal mucosa stained positive for p53 protein. There was no significant correlation between c-erb-B2 and p53 expression and age, gender, histological tumor grade, and tumor stage. In the multivariate analysis, tumor stage approached statistical significance (p=0.05), but c-erb-B2 and p53 expression was not significant (p=0.14 and p=0.29, respectively). The mean survival periods of the c-erb-B2 positive and negative groups were 26 months and 52 months, respectively (p=0.02). However, the mean survival periods of the p53 protein positive and negative patients were 34 months and 35 months, respectively (p=0.45). In conclusion, our results suggest that c-erb-B2 and p53 protein expression is strongly associated with neoplastic progression in gallbladder carcinomas, and that c-erb-B2 expression identifies patients with a worse prognosis.

Adenocarcinoma↗