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Biomedical subjects

C B Kim

Publications and source records attributed to C B Kim.

At least 37 records · Page 2Linked to original sources
PubMed1997

Retrospective comparison of infusional 5-fluorouracil, doxorubicin, and mitomycin-C (modified FAM) combination chemotherapy versus palliative therapy in treatment of advanced gastric cancer.

About one-third of patients with gastric cancer are unresectable at the time of diagnosis. Their median survival is < 6 months, with a grave prognosis. The purpose of this study was to assess the efficacy of a modified FAM (mFAM) regimen in advanced gastric cancer. We retrospectively reviewed the clinical records of 409 advanced gastric cancer patients who had not received curative surgery. Among 409 patients, 202 patients were treated with an mFAM regimen (infusional 5-FU + doxorubocin + mitomycin-C), and 207 patients received no chemotherapy (control group). No differences were found in clinical parameters between the two groups. The 1-year survival rates were 34.1% for the mFAM-treated group and 22.5% for the control group (p = 0.0135). In subset analysis, a higher 1-year survival rate was demonstrated in patients with mFAM and palliative surgery. Of the 154 evaluable patients in the mFAM-treated group, the response rate was 17.5%. In these patients, median response duration was 30 weeks, and progression-free survival was 23 weeks. Overall toxicity of mFAM regimen was relatively tolerable and reversible. In conclusion, FAM combination chemotherapy, which has been used as a standard therapy, prolonged survival after modification of the administration schedule and combination with palliative surgery. A prospective randomized study is warranted to confirm this conclusion from our retrospective study.

Adenocarcinoma↗
PubMed1996

Phylogenetic relationships of annelids, molluscs, and arthropods evidenced from molecules and morphology.

Annelids and arthropods have long been considered each other's closest relatives, as evidenced by similarities in their segmented body plans. An alternative view, more recently advocated by investigators who have examined partial 18S ribosomal RNA data, proposes that annelids, molluscs, and certain other minor phyla with trochophore larva stages share a more recent common ancestor with one another than any do with arthropods. The two hypotheses are mutually exclusive in explaining spiralian relationships. Cladistic analysis of morphological data does not reveal phylogentic relationships among major spiralian taxa but does suggest monophyly for both the annelids and molluscs. Distance and maximum-likelihood analyses of 18S rRNA gene sequences from major spiralian taxa suggest a sister relationship between annelids and molluscs and provide a clear resolution within the major groups of the spiralians. The parsimonious tree based on molecular data, however, indicates a sister relationship of the Annelida and Bivalvia, and an earlier divergence of the Gastropoda than the Annelida-Bivalvia clade. To test further hypotheses on the phylogenetic relationships among annelids, molluscs, and arthropods, and the ingroup relationships within the major spiralian taxa, we combine the molecular and morphological data sets and subject the combined data matrix to parsimony analysis. The resulting tree suggests that the molluscs and annelids form a monophyletic lineage and unites the molluscan taxa to a monophyletic group. Therefore, the result supports the Eutrochozoa hypothesis and the monophyly of molluscs, and indicates early acquisition of segmented body plans in arthropods.

Animals↗
PubMed1996

Differentiation of alpha coma from awake alpha by nonlinear dynamics of electroencephalography.

The electroencephalogram, as a probe of scalp-recorded electrical activity arising from the human cortex, provides useful information because of its temporal and spatial organization. Recent developments in nonlinear dynamics suggest that an object can be constructed in an n-dimensional space out of a temporal sequence of data such as an EEG signal and that its organization is characterized by the dimensionality of the object (in this case, human brain activity). We have carried out an analysis of a set of alpha coma EEG patterns in comparison to the awake alpha EEG patterns of normal volunteers and patients. Alpha coma recorded from a single channel is visually indistinguishable from normal resting alpha due to its similar frequency spectrum (a broad-band spectrum with 1/f characteristics). Our results show that alpha coma dimensionality, however, differs from that of normal alpha in that it has a greater variability over different temporal segments of EEG. Single channel recordings in 7 patients with alpha coma were differentiable from those of 10 subjects with "normal" EEGs. Through dynamic analysis of the EEG, novel methods of signal extraction from EEG may become evident and applicable to clinical practice.

Adult↗
PubMed1996

Accuracy of biplane and multiplane transesophageal echocardiography in diagnosis of typical acute aortic dissection and intramural hematoma.

OBJECTIVES: The purpose of this study was to evaluate the diagnostic accuracy of biplane and multiplane transesophageal echocardiography in patients with suspected aortic dissection, including intramural hematoma. BACKGROUND: Transesophageal echocardiography is a useful technique for rapid bedside evaluation of patients with suspected acute aortic dissection. The sensitivity of transesophageal echocardiography is high, but the diagnostic accuracy of biplane and multiplane transesophageal echocardiography for dissection and intramural hematoma is less well defined. METHODS: We studied 112 consecutive patients at a major referral center who had undergone biplane or multiplane transesophageal echocardiography to identify aortic dissection. The presence, absence and type of aortic dissection (type A or B, typical dissection or intramural hematoma) were confirmed by operation or autopsy in 60 patients and by other imaging techniques in all. The accuracy of transesophageal echocardiography for ancillary findings of aortic dissection (intimal flap, fenestration and thrombosis) was assessed in the 60 patients with available surgical data. RESULTS: Of the 112 patients, aortic dissection was present in 49 (44%); 10 of these had intramural hematoma (5 with and 5 without involvement of the ascending aorta). Of the remaining 63 patients without dissection, 33 (29%) had aortic aneurysm and 30 (27%) had neither dissection nor aneurysm. The overall sensitivity and specificity of transesophageal echocardiography for the presence of dissection were 98% and 95%, respectively. The specificity for type A and type B dissection was 97% and 99%, respectively. The sensitivity and specificity for intramural hematoma was 90% and 99%, respectively. The accuracy of transesophageal echocardiography for diagnosis of acute significant aortic regurgitation and pericardial tamponade was 100%. CONCLUSIONS: Biplane and multiplane transesophageal echocardiography are highly accurate for prospective identification of the presence and site of aortic dissection, its ancillary findings and major complications in a large series of patients with varied aortic pathology. Intramural hematoma carries a high complication rate and should be treated identically with aortic dissection.

Acute Disease↗
PubMed1995

Transhiatal gastric transposition of a long gap esophageal atresia.

Transhiatal gastric transposition was performed in a long gap esophageal atresia without tracheoesophageal fistula. The patient was a 12 months old female infant with previous stamm-type gastrostomy. The stomach was mobilized preserving the right gastric artery, the right gastroepiploic artery and spleen. The proximal and distal blind pouches of esophagus were excised by transcervical and transhiatal route, respectively. The mobilized stomach was pulled up into the neck through esophageal hiatus and posterior mediastinal route. The esophagogastrostomy, the only one anastomosis of this procedure, was safely performed in the neck. There were neither anastomotic leak nor early anastomotic stricture. The oral feeding was quickly established. There was no clinical evidence of regurgitation, difficulty of gastric emptying, hoarseness or respiratory problem. The low morbidity combined with satisfactory functional result indicates that the transhiatal gastric transposition is a safe and easy alternative surgical procedure for esophageal replacement in long gap esophageal atresia.

Esophageal Atresia↗
PubMed1995

Long-term follow-up of gracilis muscle transposition in children.

Sixteen children of uncontrollable fecal incontinence have been treated with Pickrell's gracilis muscle transposition since 1983: 12 had an imperforate anuses with multiple corrective operative procedures and 4 had traumatic destructions of anal sphincters. We report a series of 11 cases whom we followed-up over a period of 0.8 to 10.5 years (mean; 5.6 years). Seven patients were evaluated by anorectal manometry. All patients except one who had left hemipelvectomy and permanent colostomy showed nearly normal continence during the follow-up period. There was no evidence of fibrosis in the transposed muscles and the tensions of the transposed muscles were well maintained. The voluntary contractions of the transposed muscles were well maintained and efficient in all cases. The general manometric parameters did not correlate well with the functional results; however, there was a strong correlation in the S/R ratio (maximum squeeze pressure/resting pressure) with the functional results. We believe that the good functional outcome of this procedure need not only the meticulous surgical technique but also the personal motivation and the compliance with physiotherapy. In conclusion, although the gracilis muscle transposition never results in normal continence, acceptable continence can be achieved in the selected patients.

Adolescent↗
PubMed1994

Effects of aging on the primate visual system: spatial and temporal processing by lateral geniculate neurons in young adult and old rhesus monkeys.

1. Visual abilities decline during normal aging, and many of these declines are due to neural changes in the retina or central visual pathways. We have begun studies of the primate visual system to investigate the location and nature of these changes as well as to answer general questions about the effects of aging on neural function. We began with the dorsal lateral geniculate nucleus (LGN) because it is the main structure through which visual information passes on the way to cortex and because the parallel parvocellular and magnocellular pathways, which may be affected differently by aging, are anatomically distinct there. 2. Single-cell recordings were made in the LGN of young adult (5-16 yr) and old (25-28 yr) rhesus monkeys. We made quantitative measures of a wide variety of response properties for a large number of parvocellular (n = 257) and magnocellular (n = 113) neurons in the two groups of animals. As a result, in addition to studying the effects of aging, we were able to make quantitative comparisons between parvocellular and magnocellular neurons using larger samples than have been studied previously and for some properties that have not been studied before. 3. We found that magnocellular neurons have significantly higher maximal response rates and signal-to-noise ratios than parvocellular neurons. However, response latencies to visual stimulation were similar for neurons in the two types of layers. In agreement with previous studies, magnocellular neurons had higher maximal contrast sensitivity and higher contrast gain than parvocellular neurons. However, the sensitivity difference occurred because nearly all of the neurons with low sensitivities (< 10) were in the parvocellular layers, not because neurons in the magnocellular layers had the highest sensitivities. 4. Neurons with the smallest receptive-field centers, the highest spatial-frequency resolutions, and the highest optimal spatial frequencies were found in the parvocellular layers. However, the overall distributions of each of these properties overlapped substantially for neurons in the two types of layers, and the mean values were not significantly different. The mean high temporal-frequency cutoff was significantly higher for magnocellular than parvocellular neurons, but the difference was small (only 3 Hz), and it occurred because many parvocellular neurons had lower cutoffs than any seen in the magnocellular layers, not because magnocellular neurons had the highest temporal-frequency cutoffs. Parvocellular neurons also had narrower temporal-frequency tuning than magnocellular neurons. However, there was no significant difference in optimal temporal frequency.(ABSTRACT TRUNCATED AT 400 WORDS)

Aging↗
PubMed1994

Foveal flicker sensitivity in healthy aging eyes. II. Cross-sectional aging trends from 18 through 77 years of age.

Foveal flicker contrast sensitivity was measured for healthy adults at temporal frequencies from 2.5 to 50 Hz. The first experiment compared two-interval forced-choice (2IFC) and yes-no detection (Y-N) testing procedures for younger (19-33-year-old) and older (67-73-year-old) observers. The 2IFC technique resulted in higher absolute estimates of sensitivity. However, within a method, relative differences were similar. Therefore the two methods gave similar estimates of temporal contrast-sensitivity change with age. Experiment 2 compared 89 observers from 18 through 77 years of age to explore the effect of the time course of aging on flicker sensitivity. The 2IFC procedure was used, and retinal illuminance changes with age were controlled. Significant overall losses in contrast sensitivity were found for the 45-54, 55-64, and 65-77-year-old age groups. Overall sensitivities for the 35-44-year-old group were comparable with or (not significantly) higher than those for the 18-24- and 25-34-year-old groups. The results suggested that (1) foveal temporal contrast sensitivity does not decline until after 44 years, (2) losses after 44 years are in amplitude but not in temporal resolution of the visual response, and (3) the mean rate of loss is approximately 0.78 decilog per decade after 44 years. These results are consistent with the existence of three phases of development of temporal contrast sensitivity over the life span. The results also emphasize the importance of including healthy-eyed age-matched controls in studies of flicker sensitivity in visual dysfunctions that affect mainly older adults.

Adolescent↗
PubMed1993

Roux-en-Y end-to-side esophagojejunostomy with stapler after total gastrectomy.

One hundred gastric cancer patients who underwent total gastrectomy and Roux-en-Y, end-to-side esophagojejunostomy by using stapling devices were analyzed with regard to their operative results. The median time required for the anastomosis was 18 minutes (range of 15 to 45 minutes). A cartridge of 25 mm in diameter was preferred (85% of 25 mm vs. 15% of 28 mm). In 92 patients, procedures were uneventful. Intraoperative problems happened in 8 patients: Two misfirings of stapler due to mechanical problems, in 6 patients, doughnut tissues were incomplete. Mechanical problems were solved by a change of the stapler and for incomplete doughnut tissues, anastomosis was simply reinforced (2 cases) or reanastomosed with restaplings (4 cases). Anastomotic leakage occurred in 2 patients but it was seen only in radiological studies. During the follow up period, two cases of anastomotic stricture were found and they were treated with endoscopic dilatations. There was no operative mortality nor other complication. In addition, routine use of the Levin tube after total gastrectomy was appraised by comparing postoperative courses. Twenty patients were randomly divided into two groups; for 10 patients the Levin tube was removed at the recovery room and for another 10 patients the Levin tube was indwelled until peristalsis returned. Timing of the tube removal did not affect the duration of the hospital stay and starting day of oral intake. We think that the stapler, when properly used, can facilitate the esophagojejunostomy safely and routine use of the Levin tube after total gastrectomy may be unnecessary.

Adult↗
PubMed1992

Binocular processing in the cat's dorsal lateral geniculate nucleus. III. Spatial frequency, orientation, and direction sensitivity of nondominant-eye influences.

The present experiments examined the extent to which binocular processing in the cat's dorsal lateral geniculate nucleus (LGN) depends upon the spatial frequency, orientation, and direction of movement of stimuli presented to the nondominant eye. In Experiment 1, we tested the effects of varying these stimulus parameters on the responses of LGN cells to nondominant-eye stimulation. Sixteen of 34 cells tested had statistically significant responses to the nondominant eye and, in agreement with a previous study (Guido et al. 1989), the responsive cells were spatial-frequency sensitive. However, there was little evidence for orientation or direction sensitivity in responses to the nondominant eye: changes in discharge with changes in stimulus orientation and direction were small and were statistically significant in only nine of the cells. In Experiment 2, we tested the effects of varying spatial frequency, orientation, and direction of movement of stimuli presented to the nondominant eye on its ability to influence responses to the dominant eye (i.e., on binocular interactions). The dominant eye was stimulated with the optimal spatial frequency for the cell being tested. For 22 of 45 cells tested, nondominant-eye stimulation had a statistically significant effect on the response to the dominant eye. Fourteen of these cells showed band-pass spatial-frequency sensitivity in the nondominant-eye influence, and eight showed low-pass spatial-frequency sensitivity. However, only 11 of the cells had statistically significant variations in their binocular interactions that depended on the orientation or direction of stimuli presented to the nondominant eye. Furthermore, even for those cells, the effect of varying orientation and direction was only about half as strong as the effect of varying spatial frequency. We conclude that binocular processing in the LGN, including responses to the nondominant eye and nondominant-eye influences on responses to the dominant eye, are affected significantly by the spatial frequency of the nondominant-eye stimulus and relatively little by stimulus orientation or direction of movement. The significance of these findings for understanding the functions of LGN binocular processing is discussed.

Analysis of Variance↗
PubMed1992

Effect of duodenal switch procedure on gastric acid production, intragastric pH, gastric emptying, and gastrointestinal hormones.

The duodenal switch operation preserves the pylorus and the proximal 3 to 7 cm of duodenum in continuity with the stomach while diverting pancreaticobiliary secretions. We compared it with the Roux-en-Y without vagotomy or antrectomy in 12 dogs with innervated gastric pouches. Acid secretion was inhibited between tests using ranitidine in the Roux-en-Y group only, but two of the six dogs still developed stomal ulcers and the remainder showed stomal hyperemia. This may be due to a significant increase in gastric acid output after Roux-en-Y, but gastric emptying and plasma gastrin, cholecystokinin, secretin, gastric inhibitory polypeptide, peptide YY, and neurotensin were similar after both procedures. In 12 patients and a further 6 dogs, the duodenal switch caused no significant change in the intragastric pH environment as assessed by intragastric pH monitoring. The duodenal switch is a suitable procedure for pancreaticobiliary diversion.

Anastomosis, Roux-en-Y↗
PubMed1992

Mid-frequency loss of foveal flicker sensitivity in early stages of age-related maculopathy.

Temporal contrast sensitivity in eyes at risk for exudative age-related maculopathy (ARM) was compared to that in age-matched healthy older eyes. The test stimulus was a foveally viewed, flickering, long-wavelength 2.8 degrees diameter circle in an equiluminant (photopic) surround. Retinal illuminance and decision criterion differences were experimentally controlled. Eyes in the healthy and ARM-risk groups had 20/30 or better Snellen acuity and intraocular pressure of less than 22 mmHg. Nevertheless, the ARM-risk patients were less sensitive to flicker contrast, especially for mid-temporal frequencies. This suggests that flicker sensitivity may be useful in identifying patients at risk for exudative ARM. In addition, comparison with other research reveals a paradox: Mid-temporal frequency sensitivity losses may be attributable primarily to a "high temporal frequency" mechanism.

Aged↗
PubMed1992

Foveal flicker sensitivity discriminates ARM-risk from healthy eyes.

The "good" eyes of 13 patients with monocular exudative ARM were compared with age-matched healthy eyes of 19 subjects. Membership in the two study groups was based upon careful clinical evaluation of the tested eye as well as upon status of the fellow eye. We asked whether temporal contrast sensitivity for a long-wavelength, low spatial frequency stimulus can be used to identify the group in which a given eye belongs. Using step-wise discriminant analysis, we found that the ARM-risk and healthy eyes could be classified with 78% accuracy on the basis of foveal flicker sensitivity at two temporal frequencies--14 and 10 Hz (in order of estimated weight.)

Adult↗
PubMed1992

Preliminary evaluation of flicker sensitivity as a predictive test for exudative age-related maculopathy.

Flicker contrast sensitivity was tested in the "good" eyes of 13 patients with monocular exudative age-related maculopathy (ARM). The stimulus was a foveal, long-wavelength, low spatial frequency 2.8 degrees circle in an equiluminant (photopic) surround. Two of these ARM-risk eyes have since developed exudative ARM. Compared to healthy age-matched eyes, the two eyes that developed exudative ARM had significantly lower sensitivity at 10-40 Hz up to 9 mo before exudative symptoms appeared. The implications of these results regarding the time-course of ARM and the predictive value of foveal contrast sensitivity testing are considered. Based upon data and theoretical considerations, the authors speculate that sensitivity loss between 10 and 40 Hz is a good predictor of which eyes will develop exudative ARM. This proposal will be tested by new data from current as well as new ARM-risk subjects.

Aged↗
PubMed1991

Isolation and structural characterization of a molecular variant of dog pancreatic secretory trypsin inhibitor.

A rapid two-step method has been developed for the purification of pancreatic secretory trypsin inhibitor (PSTI) from pancreatic juice obtained from dogs, stimulated with secretin and the octapeptide of cholecystokinin. The PSTI was isolated in two biologically active molecular forms. Determination of amino acid compositions and NH2-terminal amino acid sequences demonstrated that the major form represented the intact 57-amino-acid residue peptide, and the minor form (comprising 5-10% of the total activity) represented des[Asn1 Asn2 Met3] PSTI. The metabolite arises from cleavage of a Met-Leu bond, and its formation may be a consequence of incomplete inhibition of chymotrypsinogen activation in the juice.

Amino Acid Sequence↗