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Hye Jin Choi

Publications and source records attributed to Hye Jin Choi.

18 recordsLinked to original sources
PubMed2007

Prognostic impact of resection margin involvement after extended (D2/D3) gastrectomy for advanced gastric cancer: a 15-year experience at a single institute.

BACKGROUND AND OBJECTIVES: The aim of this study was to investigate whether microscopic positive margins are detrimental to the outcome of gastric cancer patients treated with extended (D2/3) gastrectomy. METHODS: Among 2,740 consecutive patients who had undergone extended gastrectomy for advanced gastric cancer between January 1987 and December 2002, 49 patients (1.8%) had positive resection margins on final histology. RESULTS: Among 49 patients, 29 (59.2%) had proximal involved margins and 20 (40.8%) had distal involved margins. The median survival time of the positive margin group was 34 months. The negative margin group had a significantly longer median survival time of 69 months (P = 0.025). When both groups of patients were stratified according to nodal stage, a positive resection margin determined a worse prognosis only in patients with node-negative disease (174 months vs. 37 months, P = 0.0001). In patients with nodal metastasis, the median survival time was similar in both groups. CONCLUSIONS: Our results suggest that a positive microscopic margin is associated with a worse outcome in patients with node-negative disease. Therefore, a more aggressive treatment, such as re-operation, is needed in node-negative patients with a positive microscopic disease.

Adenocarcinoma↗
PubMed2006

A phase II trial of fractionated irinotecan plus carboplatin for previously untreated extensive-disease small cell lung cancer.

PURPOSE: Irinotecan plus cisplatin has been previously documented to be effective in the treatment of extensive-disease small cell lung cancer (ED-SCLC). This study was undertaken to investigate the efficacy and feasibility of combination chemotherapy of irinotecan and carboplatin in previously untreated ED-SCLC. PATIENTS AND METHODS: From December 2002 to October 2005, 39 patients with previously untreated ED-SCLC were enrolled. Patients were treated with irinotecan (50mg/m(2) IV on days 1, 8, and 15) and carboplatin (target AUC=5 IV on day 1) every 4 weeks for up to six cycles. RESULTS: Thirty-four patients (87.2%) were male and the median age was 65 years. ECOG performance status was 0-1 in 20 (51.3%) patients and 2 in 19 (48.7%) patients. The median number of chemotherapy cycles was six (range: 1-6 cycles). Thirty-five patients were assessable for response evaluation. The overall response rate was 69.2% (1 CR, 26 PR) under the intent-to-treat analysis. After a median follow-up of 22.7 months, the median time to progression was 6.4 months (95% confidence interval [CI]: 5.7-7.1 months) and median overall survival was 11.0 months (95% CI: 9.9-12.0 months). The estimated 1-year survival rate was 42.5%. In terms of toxicities, Grade 3/4 neutropenia and thrombocytopenia occurred in eight (25.6%) and five (15.4%) patients, respectively. Grade 3/4 non-hematologic toxicities included diarrhea (10.3%), anorexia (7.7%), infection (10.3%), and neutropenic fever (12.8%). There was one treatment-related death due to superimposed infection on the broncho-pleural fistula. CONCLUSION: The combination chemotherapy of irinotecan and carboplatin was effective and tolerable in previously untreated ED-SCLC patients.

Adult↗
PubMed2006

Intermediate dose 5-fluorouracil-induced encephalopathy.

As an acute neurotoxicity, high dose 5-fluorouracil (5-FU)-induced encephalopathy is well-known, but encephalopathy associated with lower dose is rarely reported. Here, we report a case of a male with anal cancer who was treated with 5-FU 1000 mg/m(2), continuous infusion for 5 days q4 weeks. At the second and the fourth cycles of chemotherapy, sudden confusion, cognitive dysfunction and disorientation occurred during 5-FU infusion. They were accompanied by hyperammonemia in the absence of focal neurological deficits or structural abnormalities. These symptoms completely disappeared and the serum ammonia level returned to normal after discontinuation of 5-FU and conservative care. In order to investigate a possible deficit of dihydropyrimidine dehydrogenase (DPD), we checked its mRNA level before and after treatment using real-time PCR. The patient's pre-treatment level was 80% compared with reference group, and it was elevated up to 187% of initial after 5-FU treatment, implying that that his encephalopathy may be 5-FU catabolite type rather than DPD deficiency. In conclusion, we report that encephalopathy can develop even with the dose of 5-FU lower than ever reported, and it should be considered as a differential diagnosis for proper management.

Aged↗
PubMed2006

Paclitaxel and leucovorin-modulated infusional 5-fluorouracil combination chemotherapy for metastatic gastric cancer.

As no standard chemotherapy regimen has been established for advanced gastric cancer, this study sought to evaluate the efficacy and safety of combination chemotherapy that included paclitaxel and leucovorin (LV)-modulated infusional 5-fluorouracil (5-FU) in metastatic gastric cancer. Patients received a three-hour infusion of 175 mg/m2 of paclitaxel on day 1. A bolus of 20 mg/m2 of LV was then administered, followed by a 24-h infusion of 1,000 mg/m2 of 5-FU on days 1 through 3. The treatment cycle was re-peated every 3 weeks until disease progression. Response evaluation was performed according to the RECIST criteria, with toxicity determined by NCI-CTC (version 2.0). A total of 66 patients, including 21 (31.8%) with a history of prior chemotherapy, were enrolled. Fifteen (71.4%) of the 21 patients with prior chemotherapy received prolonged infusional 5-FU. In the 56 evaluable patients (37 in the chemotherapy-naïve group and 19 in the prior chemotherapy group), tumor responses according to prior exposure to chemotherapy were as follows: 17 (45.9%) partial response (PR), 6 (16.2%) stable disease (SD) and 14 (37.8%) progressive disease (PD) in the chemotherapy-naïve group; 1 (7.1%) complete response, 3 (15.8%) PRs, 8 (42.1%) SDs and 7 (36.8%) PDs in the prior chemotherapy group. The overall median response duration was 20 weeks (range, 8-61 weeks), with a median progression-free survival of 20 weeks [95% confidence interval (CI), 13.4-26.6 weeks] and 12 weeks (95% CI, 5.7-18.3 weeks) in the chemotherapy-naïve and prior chemotherapy groups, respectively. The median overall survival was 48 weeks (95% CI, 38-58 weeks) in the chemotherapy-naïve group and 28 weeks (95% CI, 22-34 weeks) in the prior chemotherapy group. The most frequent grade III/IV toxicity was neutro-penia. Non-hematological toxicity of grade III/IV was rare. Paclitaxel in combination with 5-FU/LV is clinically beneficial for patients with advanced gastric cancer and is a feasible salvage regimen for 5-FU-refractory gastric cancer patients.

Adult↗
PubMed2005

A pilot study of trans-arterial injection of 166Holmium-Chitosan complex for treatment of small hepatocellular carcinoma.

Percutaneous approaches, such as percutaneous ethanol injection and radiofrequency ablation, have been most widely used for hepatocellular carcinoma patients who were not eligible for surgery. New technologies to improve the efficacy are currently needed. (166)Holmium is a neutron activated radionuclide, and has several beneficial radiophysical characteristics for internal radiation therapy. (166)Holmium-Chitosan complex, in which chitosan is chelated with (166)Holmium, was developed as a radiopharmaceutical for cancer therapy. We have conducted a pilot study to evaluate the clinical efficacy of transarterial administration of (166)Holmium-Chitosan complex in patients with a single and small (< 3 cm) hepatocellular carcinoma. (166)Holmium-Chitosan complex, at a dose of 20 mCi per cm of tumor mass-diameter, was administered through the artery that directly fed the tumor. Twelve patients were treated with a median follow-up duration of 26 (range: 12-61) months. The tumor diameter ranged between 1.5 and 2.5 cm. Ten patients (83%) had complete response and two (17%) had partial response. The median complete response duration was not reached. The median AFP level declined from 83.8 to 8.3 ng/mL within 2 months after treatment. No grade III/IV toxicity was observed. Grade I and II toxicities were observed in four patients (2 abdominal pain, 1 fever, and 1 AST/ALT elevation). No toxic death occurred. This preliminary study shows a promising and durable complete response rate with an acceptable safety profile. Further studies with greater accrual of patients are warranted.

Adult↗
PubMed2004

Dynamic and redox active pillared bilayer open framework: single-crystal-to-single-crystal transformations upon guest removal, guest exchange, and framework oxidation.

A metal-organic pillared bilayer open framework having 3D channels, [Ni(2)(C(26)H(52)N(10))](3)[BTC](4).6C(5)H(5)N.36H(2)O (BOF-1, 1), has been assembled from bismacrocyclic nickel(II) complex [Ni(2)(C(26)H(52)N(10))(Cl)(4)].H(2)O and sodium 1,3,5-benzenetricarboxylate (Na(3)BTC). The channels are occupied by pyridine and water guest molecules. When the single crystal of 1 was dried in air and then heated at 75 degrees C for 1.5 h, respectively, [Ni(2)(C(26)H(52)N(10))](3)[BTC](4).30H(2)O (1') and [Ni(2)(C(26)H(52)N(10))](3)[BTC](4).4H(2)O (2) resulted with retention of the single crystallinity. The X-ray structures reveal spongelike dynamic behavior of the bilayer framework that reduces the interlayer distance in response to the amount of guest molecules. Solid 2 differentiates various alcohols. When 1 was immersed in pyridine and benzene, guest molecules were exchanged with retention of the single-crystal nature to give rise to [Ni(2)(C(26)H(52)N(10))](3)[BTC](4).20pyridine.6H(2)O (3) and [Ni(2)(C(26)H(52)N(10))](3)[BTC](4).14benzene.19H(2)O (4), respectively. Furthermore, crystal 1 reacted with I(2) via single-crystal-to-single-crystal transformation to produce [Ni(2)(C(26)H(52)N(10))](3)[C(9)H(3)O(6)](4)(I(3))(4).nI(2).17H(2)O (5) that consists of positively charged framework incorporating nickel(III) and nickel(II) ions and the channels including I(3)(-) and I(2).

Journal Article↗
PubMed2004

Congenital absence of inferior vena cava as a rare cause of pulmonary thromboembolism.

Interruption of the inferior vena cava (IVC) with azygos continuation is an uncommon vascular anomaly that results from aberrant development during embryogenesis. We report a rare case of this anomaly, presenting with massive pulmonary embolism. Subsequent evaluation with abdominal CT scan revealed the congenital absence of retrohepatic IVC. The patient was successfully treated with anticoagulation. When deep venous thrombosis (DVT) develops in patients with no apparent risk factors, the presence of congenital IVC anomalies should be considered.

Adult↗
PubMed2004

Raising the spin-reversal barrier in cyano-bridged single-molecule magnets: linear Mn(III)(2)M(III)(CN)(6) (M = Cr, Fe) species incorporating [(5-Brsalen)Mn](+) units.

Reactions between K(3)[M(CN)(6)] and [Mn(5-Brsalen)(H(2)O)(2)](+) (5-Brsalen = N,N'-ethylenebis(5-bromosalicylidene)aminato dianion) in a mixture of methanol and water afford the compounds K[(5-Brsalen)(2)(H(2)O)(2)Mn(2)M(CN)(6)].2H(2)O, with M = Cr (1) or Fe (2). The two compounds are isostructural, each containing a molecular cluster with a linear Mn(III)-NC-M(III)-CN-Mn(III) core and tetragonally elongated coordination about the Mn(III) centers. Magnetic data indicate the presence of weak exchange interactions within the clusters, giving rise to ground states of S = (5)/(2) and (9)/(2) with significant zero-field splitting. Despite the proximity of spin-excited states, ac susceptibility data reveal frequency-dependent out-of-phase signals characteristic of single-molecule magnets with spin-reversal barriers of U(eff) = 16 and 25 cm(-)(1), respectively.

Journal Article↗
PubMed2003

Caspase-3-mediated cleavage of Cdc6 induces nuclear localization of p49-truncated Cdc6 and apoptosis.

We show that Cdc6, an essential initiation factor for DNA replication, undergoes caspase-3-mediated cleavage in the early stages of apoptosis in HeLa cells and SK-HEP-1 cells induced by etoposide, paclitaxel, ginsenoside Rh2, or tumor necrosis factor-related apoptosis-inducing ligand. The cleavage occurs at the SEVD442/G motif and generates an N-terminal truncated Cdc6 fragment (p49-tCdc6) that lacks the carboxy-terminal nuclear export sequence. Cdc6 is known to be phosphorylated by cyclin A-cyclin dependent kinase 2 (Cdk2), an event that promotes its exit from the nucleus and probably blocks it from initiating inappropriate DNA replication. In contrast, p49-tCdc6 translocation to the cytoplasm is markedly reduced under the up-regulated conditions of Cdk2 activity, which is possibly due to the loss of nuclear export sequence. Thus, truncation of Cdc6 results in an increased nuclear retention of p49-tCdc6 that could act as a dominant negative inhibitor of DNA replication and its accumulation in the nucleus could promote apoptosis. Supporting this is that the ectopic expression of p49-tCdc6 not only promotes apoptosis of etoposide-induced HeLa cells but also induces apoptosis in untreated cells. Thus, the caspase-mediated cleavage of Cdc6 creates a truncated Cdc6 fragment that is retained in the nucleus and induces apoptosis.

Active Transport, Cell Nucleus↗
PubMed2003

Nickel(II) macrocyclic complexes with long alkyl pendant chain: synthesis, x-ray structure, and anion exchange property in the solid state.

A nickel(II) pentaaza macrocyclic complex containing a 1-hexadecyl pendant chain, [Ni(C(25)H(55)N(5))](ClO(4))(2).H(2)O (1), was synthesized by a one-pot metal-template condensation reaction. Crystal data for 1: triclinic, Ponemacr;, a = 8.333(4) A, b = 8.356(3) A, c = 28.374(9) A, alpha = 81.865(19) degrees, beta = 86.242(18) degrees, gamma = 63.871(17) degrees, Z = 2. Solid 1 forms hydrophobic layers that are constructed by the long alkyl chains of the macrocycles. Solid 1 exchanges ClO(4)(-) with NCS(-), PF(6)(-), C(2)O(4)(2-), NO(3)(-), and CF(3)SO(3)(-) that are dissolved in water. From the reaction of [Ni(C(25)H(55)N(5))Cl(2)] with Et(3)NH(TCNQ)(2) in EtOH/DMF/acetone solution, [Ni(C(25)H(55)N(5))(TCNQ)(2)](TCNQ).(CH(3)COCH(3)) (2) (TCNQ = 7,7,8,8-tetracyano-p-quinodimethane) was prepared. Crystal data for 2: triclinic, Ponemacr;, a = 8.459(0) A, b = 13.945 (1) A, c = 26.833(2) A, alpha = 88.744(2) degrees, beta = 84.536(2) degrees, gamma = 80.089(4) degrees, Z = 2. In 2, TCNQ anions coordinate nickel(II) at the axial sites, which form pi-stacked TCNQ(-) dimers to give rise to 1-D chains. The neutral TCNQ molecules are included between the dimerized TCNQ(-) species, which construct a pi-stacked group of six TCNQ units as blocked by the long alkyl chains. Compound 2 is an electric insulator. It shows a weak signal in the EPR spectrum. The magnetic susceptibility data of 2 measured at 5-300 K exhibit a simple paramagnetism at low temperatures (<100 K) but an increase in the magnetic moment at higher temperatures due to the contribution of a thermally accessible triplet state for the antiferromagnetically coupled [TCNQ](2)(2-).

Journal Article↗
PubMed2002

A metal-organic bilayer open framework with a dynamic component: single-crystal-to-single-crystal transformations.

A metal-organic bilayered open framework, [Ni2(C26H52N10)]3[BTC]4.6C5H5N.36H2O (BOF-1, 1), has been prepared by the self-assembly of a new bismacrocyclic nickel(II) complex [Ni2(C26H52N10)(Cl)4].H2O (A) and sodium 1,3,5-benzenetricarboxylate (Na3BTC) in the mixture of water/DMSO/pyridine. The X-ray crystal structure of 1 shows that 2D layers with the cavities of brick-wall motifs (22.6 x 14.3 A2) are formed by the coordination of the nickel(II) complex with BTC3- ions and that the two 2D layers are linked with the p-xylyl bridging groups of the bismacrocycles as pillars to generate 3D channels in the bilayered framework. The voids of the channels occupy 61% of the total volume, which are filled with pyridine and water guest molecules. When 1 was dried at 75 degrees C for 1.5 h, [Ni2(C26H52N10)]3[BTC]4.4H2O (2) resulted by maintaining the single-crystallinity, which exhibited a dramatic decrease in the interlayer spacing as well as changes in the cell parameters. Solid 2 differentiates various alcohols such as MeOH, EtOH, isopropyl alcohol, and benzyl alcohol in toluene. When 1 was immersed in insoluble solvents such as pyridine and benzene, some guest molecules were exchanged with the aromatic molecules to give [Ni2(C26H52N10)]3[BTC]4.20pyridine.6H2O (3) and [Ni2(C26H52N10)]3[BTC]4.14benzene.19H2O (4), respectively. The guest-exchange processes also involve single-crystal-to-single-crystal transformation.

Journal Article↗
PubMed2002

Isolation of an oxomanganese(V) porphyrin intermediate in the reaction of a manganese(III) porphyrin complex and H2O2 in aqueous solution.

The reaction of [Mn(TF(4)TMAP)](CF(3)SO(3))(5) (TF(4)TMAP=meso-tetrakis(2,3,5,6-tetrafluoro-N,N,N-trimethyl-4-aniliniumyl)porphinato dianion) with H(2)O(2) (2 equiv) at pH 10.5 and 0 degrees C yielded an oxomanganese(V) porphyrin complex 1 in aqueous solution, whereas an oxomanganese(IV) porphyrin complex 2 was generated in the reactions of tert-alkyl hydroperoxides such as tert-butyl hydroperoxide and 2-methyl-1-phenyl-2-propyl hydroperoxide. Complex 1 was capable of epoxidizing olefins and exchanging its oxygen with H(2) (18)O, whereas 2 did not epoxidize olefins. From the reactions of [Mn(TF(4)TMAP)](5+) with various oxidants in the pH range 3-11, the O-O bond cleavage of hydroperoxides was found to be sensitive to the hydroperoxide substituent and the pH of the reaction solution. Whereas the O-O bond of hydroperoxides containing an electron-donating tert-alkyl group is cleaved homolytically, an electron-withdrawing substituent such as an acyl group in m-chloroperoxybenzoic acid (m-CPBA) facilitates O-O bond heterolysis. The mechanism of the O-O bond cleavage of H(2)O(2) depends on the pH of the reaction solution: O-O bond homolysis prevails at low pH and O-O bond heterolysis becomes a predominant pathway at high pH. The effect of pH on (18)O incorporation from H(2) (18)O into oxygenated products was examined over a wide pH range, by carrying out the epoxidation of carbamazepine (CBZ) with [Mn(TF(4)TMAP)](5+) and KHSO(5) in buffered H(2) (18)O solutions. A high proportion of (18)O was incorporated into the CBZ-10,11-oxide product at all pH values but this proportion was not affected significantly by the pH of the reaction solution.

Carbamazepine↗
PubMed2002

[Clinical efficacy of serum PIVKA-II in the diagnosis and follow up after treatment of hepatocellular carcinoma].

BACKGROUND/AIMS: Protein induced by vitamin K absence or antagonist II (PIVKA-II) appears to be a useful tumor marker for the evaluation of patients with hepatocellular carcinoma (HCC). But the usefulness of PIVKA-II was not yet clear in Korea where hepatitis B-virus is endemic. We investigated the usefulness of PIVKA-II in the diagnosis and follow-up after treatment of HCC. METHODS: We studied patients with HCC which was pathologically confirmed. PIVKA-II was measured by enzyme immunoassay. PIVKA- levels before and after treatment, in correlation with imaging studies, were analyzed for the comparison of treatment responses. Kappa index was obtained. RESULTS: A total of 129 patients were included. 93 patients (72%) were HBsAg positive. 86 patients (67%) were PIVKA-II >40 mAU/mL. 52 patients (40%) were AFP >20 ng/mL and 77 patients (60%) were AFP < or = 20 ng/mL. Of 77 patients, 40 patients (52%) showed PIVKA-II >40 mAU/mL. 68 of 129 patients were evaluated treatment response. On the basis of radiologic response, CR was 33, PR 17, SD 12, and PD 6. Of the 33 radiologic CR patients, 30 patients were CR and 3 patients were PR by means of PIVKA-II response. Of the 17 radiologic PR patients, 6 patients were CR and 7 patients were PR. Therefore, tumor responses by radiologic and PIVKA-II were well correlated (Kappa index was 0.59). CONCLUSIONS: PIVKA-II can be used as a useful tumor marker for patients with HCC, especially those with low levels of AFP, before and after treatment in Korea.

Biomarkers↗