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K Kim

Publications and source records attributed to K Kim.

At least 55 records · Page 3Linked to original sources
PubMed2004

Auditory evoked field responses in the left hemisphere to morphosyntactic violations in Korean sentence.

To investigate multiple cortical regions associated with syntactic processes at the sentence level, auditory evoked field responses to morphosyntactic violations were measured over the left hemisphere of seven subjects. Subjects were asked to judge the acceptability of the final verb in verb-ending Korean sentence. Measured field data were transformed to the fields that would be detected on a standard sensing plane and averaged across subjects in different violation conditions. In the grand average data, we found distinct features at latencies of 400 ms and 600 ms, which seem to be specific to morphosyntactic processes. Equivalent current dipoles (ECDs) plotted on a standard brain indicate the inferior frontal region and the superior temporal gyrus for 400 ms component, and the middle temporal gyrus for 600 ms component. Our MEG study localized the distinct cortical regions involved in syntactic processes, which may be reflected in LAN and P600 of ERP.

Acoustic Stimulation↗
PubMed2004

Averaging algorithm based on data statistics in magnetocardiography.

An algorithm for automatic averaging of a magnetocardiogram (MCG) is described. Due to the relatively low signal-to-noise ratio in the MCG, the measured MCG data are often averaged to be analyzed. Generally, R-peaks are used as trigger points, which become anchors for superposition and we can obtain an averaged epoch eventually. However, we have to determine several parameters, such as the threshold magnitude for recognizing R-peak, the time-period of the epoch window, and which channel has dominant R-peaks. In order to determine these parameters automatically, we utilize the magnitude histogram of the root-mean-square waveform of all the channels. We can determine the threshold magnitudes for recognizing R-peaks and T-peaks, respectively, by using the characteristic distribution of the MCG signal histogram. Peak detection procedure using these thresholds records all the locations of the R-peaks and T-peaks, thus we get the average latencies of the R-T intervals and the R-R intervals. From these latencies, we estimate the full width of the epoch window. By adding a routine for processing double R-peaks, our algorithm could conduct the MCG averaging sequence fully automatically. The algorithm has been tested on recordings of 40 normal subjects and 15 patients suffering from myocardial ischemia, and we conclude that this algorithm reliably performs the averaging sequence. The MCG recordings are measured by our 62-channel planar gradiometer system in a magnetically shielded room.

Algorithms↗
PubMed2004

Combination chemotherapy with epirubicin, docetaxel and cisplatin (EDP) in metastatic or recurrent, unresectable gastric cancer.

Based on single agent activities and the additive or synergistic effects of three individual drugs in gastric cancer, we performed a phase II study of a new regimen combining epirubicin, docetaxel and cisplatin (EDP) for unresectable gastric cancer. The patients with histologically confirmed metastatic or recurrent, unresectable gastric cancer and no history of palliative chemotherapy were eligible for this trial. In total, 40 mg m(-2) epirubicin (reduced to 30 mg m(-2) due to high incidence of febrile neutropaenia; 75%) intravenously (i.v.) over 30 min, followed by 60 mg m(-2) docetaxel i.v. over 1 h, then 75 mg m(-2) cisplatin i.v. over 1 h was administered every 3 weeks. Between January 2002 and February 2003, 30 patients (epirubicin 40 mg m(-2), eight; 30 mg m(-2), 22) were enrolled. The median age was 52 years (range, 33-68). The patients received a median of four cycles (range, 1-8). One patient (3%) achieved a complete response, 13 (43%) showed partial responses, 13 (43%) had stable diseases and three (10%) progressed. The overall response rate was 47% (95% CI, 28-66%), and the median duration of response was 5.0 months (95% CI, 3.0-7.0). The median time to progression was 4.1 months (95% CI, 2.4-5.9), and the median overall survival was 11.0 months (95% CI, 9.5-12.4). Grade 4 neutropaenia were observed in 41%, and febrile neutropaenia in 32%, out of the patients receiving 30 mg m(-2) of epirubicin. Grade 3 nonhaematological toxicities included nausea, vomiting, anorexia and peripheral neuropathy. In conclusion, EDP is active in gastric cancer, with a manageable and predictable toxicity profile.

Adult↗
PubMed2004

Axial patterning of C. elegans male sensilla identities by selector genes.

The fan and rays of the C. elegans male tail constitute a compound sensory organ essential for mating. Within this organ, the individual sensilla, known as rays, have unique identities. We show that ray identities are patterned by a selector gene mechanism in a manner similar to other serially homologous axial structures. One selector gene that promotes the identities of a subset of the rays is the Hox gene egl-5. Within EGL-5-expressing rays, further patterning is provided by a Pax-6 homolog and a signal of the TGFbeta family. These genes and pathway coordinately specify multiple ray properties affecting all three terminal ray cell types. These properties include complex patterns of FMRFamide-like (FaRP) neuropeptides, serotonin (5HT) and dopamine expression, and ray morphology. Differences in these differentiated characteristics give each sensillum a unique identity and potentially endow the compound ray organ with a higher-order information gathering capacity.

Animals↗
PubMed2004

Measurement of the flux of ultrahigh energy cosmic rays from monocular observations by the High Resolution Fly's Eye experiment.

We have measured the cosmic ray spectrum above 10(17.2) eV using the two air-fluorescence detectors of the High Resolution Fly's Eye observatory operating in monocular mode. We describe the detector, phototube, and atmospheric calibrations, as well as the analysis techniques for the two detectors. We fit the spectrum to a model consisting of galactic and extragalactic sources.

Journal Article↗
PubMed2004

Comparison of the toxicity using body residues of DDE and select PCB congeners to the midge, Chironomus riparius, in partial-life cycle tests.

Due to the long time course required to achieve steady state with highly lipophilic contaminants such as PCBs (polychlorinated biphenyls), data derived from short-term toxicity tests may lead to an erroneous interpretation of hazard. In addition, PCBs bioaccumulated over time can cause sublethal impairments in organisms at concentrations much lower than required for mortality. Here, the body residues of 1,1-dichloro-2,2-bis-p-chlorophenyl ethane (DDE) and select PCB congeners associated with a spectrum of chronic effects in the midge, Chironomus riparius, were evaluated. The route of exposure was ingestion of the PCB-contaminated alga, Chlorella vulgarus, and trout chow loaded with the selected test compound. Two separate exposures of midges were performed. In the first experiment, midges were exposed from the second instar to the pupal stage. In the second exposure, midges were exposed from the second instar to the adult stage. A variety of sublethal endpoints was monitored, including developmental time within a stadium, body weight, and fecundity for the female adult. The dose was assessed as the whole body residue concentration of the contaminant. Overall, the midge concentration increased with increasing exposure concentration in algae and trout chow. Body weight at the end of each stadium was the assessment parameter that was least significantly affected among the test endpoints monitored. In contrast, a significant increase in development time was the endpoint that was most frequently observed in response to contaminant exposure. Reduction in fecundity was found only for DDE-exposed midges. These data, in which chronic endpoints are related to body residues, suggest that body residues will be useful in defining sublethal hazards of DDE and some PCB congeners.

Administration, Oral↗
PubMed2004

Perivascular-submandibular lymph node metastasis in squamous cell carcinoma of the tongue and floor of mouth.

AIMS: The goal of this study was to investigate the incidence of occult metastasis in perivascular lymph node and nodal recurrence in these nodal pads in squamous cell carcinoma (SCC) of the tongue and floor of mouth. METHODS: We performed a prospective analysis of the incidence of an occult metastasis in the perivascular lymph nodes in 55 patients (41 with an oral tongue carcinoma and 14 with a mouth floor carcinoma) who underwent an elective supraomohyoid neck dissection (SOHND) for SCC of the tongue and floor of mouth, from 1997 to 2002. 99 SOHND procedures were performed as follows: 72 in tongue carcinomas and 27 in the mouth floor carcinomas. RESULT: Clinically occult, but pathologically positive perivascular lymph nodes occurred in four of 72 of the tongue carcinomas and two of 27 of the mouth floor carcinomas. The incidence of the regional recurrence at level I was three of 45. CONCLUSIONS: This preliminary report reveals a small incidence of perivascular lymph-node metastases and the infrequent nodal recurrence in this area after SOHND in early-staged tongue and floor of mouth SCC.

Adult↗
PubMed2004

The Mainz Severity Score Index: a new instrument for quantifying the Anderson-Fabry disease phenotype, and the response of patients to enzyme replacement therapy.

Anderson-Fabry disease (AFD) is an X-linked disorder caused by deficient activity of the lysosomal enzyme alpha-galactosidase A. The availability of enzyme replacement therapy (ERT) for this debilitating condition has led to the need for a convenient and sensitive instrument to monitor clinical effects in an individual patient. This study aimed to develop a scoring system--the Mainz Severity Score Index (MSSI)--to measure the severity of AFD and to monitor the clinical course of the disease in response to ERT. Thirty-nine patients (24 males and 15 females) with AFD were assessed using the MSSI immediately before and 1 year after commencing agalsidase alfa ERT. Control data were obtained from 23 patients in whom AFD was excluded. The MSSI of patients with AFD was significantly higher than that of patients with other severe debilitating diseases. The MSSI indicated that, although more men than women had symptoms classified as severe, overall, the median total severity scores were not significantly different between male and female patients. One year of ERT with agalsidase alfa led, in all patients, to a significant (p < 0.001) reduction in MSSI score (by a median of nine points). This study has shown that the MSSI score may be a useful, specific measure for objectively assessing the severity of AFD and for monitoring ERT-related treatment effects.

Adolescent↗
PubMed2004

Capecitabine monotherapy in patients with anthracycline- and taxane-pretreated metastatic breast cancer.

The selection of chemotherapeutic regimens is challenging for metastatic breast cancer (MBC) patients whose diseases have failed to respond to anthracyline and taxane. Capecitabine has advantages of oral administration and favorable toxicity profiles. This study was conducted to evaluate the efficacy of capecitabine and to identify the subgroup of patients who would potentially have benefit from capecitabine monotherapy in patients with anthracycline- and taxane-pretreated MBC. Female patients with MBC who had been previously treated with anthracycline and taxane received oral capecitabine 2500 mg/m(2) divided in two doses daily for 2 wk with 1-wk rest period. Between September, 1999, and December, 2002, a total of 38 patients were enrolled. Among the 36 evaluable patients, one patient achieved a complete response (CR), 9 patients had partial responses (PRs), and 13 patients had stable diseases (SDs). Response rate was 26% [95% confidence interval (CI), 12-40%] and the tumor control rate (TCR, CR+PR+SD) was 61% (95% CI, 45-77%). The median follow-up duration was 27.8 mo. The median duration of response was 8.9 mo, the median time to progression was 4.6 mo, and the median overall survival was 18.1 mo. The major toxicities were hand-foot syndrome, diarrhea, and emesis. There was no treatment-related death. The predictors of better overall survival were positivity of hormone receptor, disease-free survival longer than 1 yr, non-refractoriness to anthracycline, and fewer number (<or= 3) of involved organs. Capecitabine monotherapy is effective and well tolerated for MBC patients who had previously been treated with anthracycline and taxane. The TCR could predict overall survival as well as the objective response in this study, suggesting a possible role of TCR as a surrogate marker for survival in MBC patients on salvage chemotherapy. The patients who have relatively slow growing tumor and less tumor burden could have benefit from capecitabine monotherapy following anthracycline- and taxane-based chemotherapy.

Administration, Oral↗
PubMed2004

Targeted degradation of proteins by small molecules: a novel tool for functional proteomics.

A novel strategy that targets protein for degradation has recently been developed by exploiting a protein-targeting chimeric molecule ('Protac'). Typically, the chimeric Protac is composed of a small-molecule ligand ('bait') on one end and a synthetic octapeptide on the other. This octapeptide is recognized by E3 ubiquitin ligase pVHL (von Hippel Lindau tumor suppressor protein), thereby recruiting a small molecule-bound protein ('prey') to pVHL for ubiquitination and degradation. Since selective degradation of a cellular protein generates a "loss of function" mutation, this protein knock-out strategy may be useful to study the function of a given protein or to evaluate whether a cellular protein is a potential target for drug intervention, in a manner reminiscent of gene knock-out or siRNA approaches. Herein, we show that a synthetic pentapeptide is sufficient to interact with pVHL E3 ligase, and that the pentapeptide-based Protac efficiently induces ubiquitination and degradation of target protein. Our results also demonstrate that the pentapeptide-based Protac can enter cells efficiently to exerts its biological activity effectively. These results suggest that the synthetic pentapeptide can be used either directly in the preparation of cell-permeable Protacs or as a template to develop peptidomimetic or non-peptide Protacs.

Blotting, Western↗
PubMed2003

Observation of an exotic S = +1 baryon in exclusive photoproduction from the deuteron.

In an exclusive measurement of the reaction gammad-->K(+)K(-)pn, a narrow peak that can be attributed to an exotic baryon with strangeness S=+1 is seen in the K(+)n invariant mass spectrum. The peak is at 1.542+/-0.005 GeV/c(2) with a measured width of 0.021 GeV/c(2) FWHM, which is largely determined by experimental mass resolution. The statistical significance of the peak is (5.2+/-0.6)sigma. The mass and width of the observed peak are consistent with recent reports of a narrow S=+1 baryon by other experimental groups.

Journal Article↗
PubMed2003

Hand-assisted laparoscopic colorectal surgery using GelPort.

BACKGROUND: An easily usable hand access device will optimize success in hand-assisted laparoscopic surgery (HALS). The authors describe their initial series of HALS colorectal resections using GelPort to evaluate their current technique and results with this new device. METHODS: A retrospective study investigated 33 HALS colorectal procedures including total colectomy ( n = 16) and low anterior resection ( n = 10). All operative data, including intraoperative GelPort performance, were prospectively recorded and retrospectively analyzed. RESULTS: In this study, 3 (9.1%) of 33 HALS procedures were converted to open surgery, and 4 (13.3%) of 30 HALS procedures required minimal enlargement of incisions to facilitate extracorporeal procedures. The operative time was 263 +/- 85 min, and the blood loss was 282 +/- 148 ml. There were no device malfunctions. Three major complications (9.1%) and 7 minor wound infections (21%) were noted postoperatively. The mean hospital stay was 7.9 +/- 3.8 days. CONCLUSION: When performed with GelPort, HALS is safely and reliably applicable for various colorectal procedures.

Adult↗
PubMed2003

Measurement of ep-->e' ppi+ pi- and baryon resonance analysis.

The cross section for the reaction ep-->e(')ppi(+)pi(-) was measured in the resonance region for 1.4<W<2.1 GeV and 0.5<Q2<1.5 GeV(2)/c(2) using the CLAS detector at Jefferson Laboratory. The data show resonant structures not visible in previous experiments. The comparison of our data to a phenomenological prediction using available information on N(*) and Delta states shows an evident discrepancy. A better description of the data is obtained either by a sizable change of the properties of the P13(1720) resonance or by introducing a new baryon state, not reported in published analyses.

Journal Article↗
PubMed2003

Development of a nanostructured DNA delivery scaffold via electrospinning of PLGA and PLA-PEG block copolymers.

The present work utilizes electrospinning to fabricate synthetic polymer/DNA composite scaffolds for therapeutic application in gene delivery for tissue engineering. The scaffolds are non-woven, nano-fibered, membranous structures composed predominantly of poly(lactide-co-glycolide) (PLGA) random copolymer and a poly(D,L-lactide)-poly(ethylene glycol) (PLA-PEG) block copolymer. Release of plasmid DNA from the scaffolds was sustained over a 20-day study period, with maximum release occurring at approximately 2 h. Cumulative release profiles indicated amounts released were approximately 68-80% of the initially loaded DNA. Variations in the PLGA to PLA-PEG block copolymer ratio vastly affected the overall structural morphology, as well as both the rate and efficiency of DNA release. Results indicated that DNA released directly from these electrospun scaffolds was indeed intact, capable of cellular transfection, and successfully encoded the protein beta-galactosidase. When tested under tensile loads, the electrospun polymer/DNA composite scaffolds exhibited tensile moduli of approximately 35 MPa, with approximately 45% strain initially. These values approximate those of skin and cartilage. Taken together, this work represents the first successful demonstration of plasmid DNA incorporation into a polymer scaffold using electrospinning.

Animals↗
PubMed2003

Needles to promote ventricular blood into the ischemic myocardium applied in a rat heart transplant model: an acute observation [corrected].

Two needles were designed in order to revascularize an ischemic myocardium in the event of left coronary artery occlusion. This study was conducted by performing the Lee modified Fox-Montorsi heart-lung transplant on 25 San Diego Microsurgical Institute-bred Sprague Dawley rats that were subjected to left coronary artery ligation in each case. Of these 25 rats, a straight-porous (SP) needling procedure was applied to 9 heterotopically transplanted rat hearts, and a distinct horseshoe (HS)-shaped needle application was performed on the remaining 16 heterotopically transplanted rat hearts. This report represents an acute study on the efficiency of these two needles to transmit oxygen-rich blood from the left ventricle into the ischemic myocardium. Doppler readings for male vs. female transplants showed that the control peak (PK) and mean (MN) kHz values are on the average of 0.20 kHz higher in males than in females. However, control heart rate values in both sexes are approximately equal. Ligation of the left coronary artery caused a dramatic decrease of PK and MN kHz values in both sexes, while heart rate showed no significant decrease from the original control values in response to ischemia. Application of the SP needle showed only a slight return of PK and MN values in both sexes, but heart rate values increased to levels higher than the original control values. The HS needling procedure was able to recover approximately 80% of the control PK and MN kHz values in both sexes. Thus, these data indicate that the HS needle can successfully transmit left ventricular blood into the myocardium.

Animals↗
PubMed2003

Consecutive en-bloc liver (30%)-pancreas-duodenum-spleen-stomach transplant in Lewis rats.

It is well-known that 30% of the remaining liver mass, following partial hepatectomy, regenerates to full original mass within 2 weeks in rats. In order to carry the transplanted rat liver to repeated transplantation, a technique of combining 30% of the liver with the pancreaticoduodenum and spleen transplantation is performed in this consecutive organ transplantation study. Our laboratory observed several 37-month-old transplanted rats by carrying through 2-3 generations, and histological disclosure were made. Because the partial liver transplants did not regenerate after the transplantation with other splanchnic organs, this technique is not so difficult though subsequent surgical maneuvers are needed and the liver histology proved entirely normal in every aspect when followed beyond the rat's life span of 24 months.

Animals↗
PubMed2003

Observations of rat ovarian-splenic consecutive transplants.

We examined the results after implantation of ovarian follicles by various modes in a total of 82 cases. One or five ovarian follicles were implanted into spleens in castrated female rats. In 20 cases among these, each five follicles were implanted into native and transplanted spleens after spleen transplantation (double implantation of the ovary). Through consecutive spleen transplantation, we observed the results beyond the rat's life span for a limited period. In many cases, we found a more aggressive form of malignant tumor, i.e., dysgerminoma. We present the results and discuss the modes of implantations and possible pathogenetic mechanisms of tumor formation.

Animals↗