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Biomedical subjects

Y D Kim

Publications and source records attributed to Y D Kim.

At least 37 records · Page 2Linked to original sources
PubMed2000

Upper airway resistance syndrome and its treatment.

Although upper airway resistance syndrome (UARS) is being recognized by a growing number of specialists, its prevalence remains unknown. UARS is associated with nocturnal and daytime complaints and oro-naso-maxillo-mandibular signs. Spectrum analysis of the nocturnal sleep EEG from the central leads indicates significant differences in absolute power in the 12-14 Hz and the 7-9 Hz bands of UARS patients compared to controls. The 0.5-2.0 Hz band also appears to be involved when analyses performed on matched controls are compared to results obtained in subjects treated with nasal CPAP. Several treatment avenues--nasal CPAP, dental devices, surgical procedures, and radiofrequency thermal ablation--have been used for the treatment of UARS. The number of subjects treated have been too low and the protocols too limited to arrive at appropriate outcome recommendations, but many of the approaches have shown positive results, suggesting the possibility of several treatment avenues.

Electroencephalography↗
PubMed2000

Clinical implication of altered expression of Mad1 protein in human breast carcinoma.

BACKGROUND: Mad1 protein is known to repress Myc target genes and antagonize Myc function. The authors undertook this study to investigate the clinical implication of Mad1 expression in human breast carcinoma. METHODS: The authors performed immunohistochemical assays for Mad1 and Myc proteins in human breast carcinoma, along with tissues from normal breast and benign diseases. The data from protein assays were analyzed in terms of the clinical and biologic characteristics of the patients. RESULTS: Of 66 patients with invasive ductal carcinoma, Mad1 expression was detected in 22 (33. 3%). Intensity and area of Mad1 expression significantly decreased in DCIS and invasive cancers, whereas high levels of Mad1 expression were persistent in benign breast lesions. Mad1 expression was significantly reduced in poorly differentiated tumors (P < 0.001). Expression of Mad1 was not associated with tumor size, lymph node status, or stage of disease. The authors did not observe any correlation between S-phase and expression status of Myc or Mad1. Mad1 expression was closely linked to differentiation of the cancer cells and inversely correlated with Myc expression (P = 0.042). In survival analysis, Mad1 was a significant factor in predicting recurrence of the disease, but not overall survival after CMF chemotherapy. CONCLUSIONS: In human breast carcinoma cells, expression of Mad1 seems to be down-regulated, whereas expression of Myc is amplified. Altered expression of Mad1 may play a role in the malignant transformation of human mammary epithelial cells and represent an aggressive phenotype in human breast carcinoma.

Adult↗
PubMed2000

Actin-binding cellular proteins inside human immunodeficiency virus type 1.

Host proteins are incorporated both on and inside human immunodeficiency virus type 1 (HIV-1) virions. To identify cellular proteins inside HIV-1, virion preparations were treated by a protease-digestion technique that removes external host proteins, allowing for the study of the proteins inside the virus. Treated HIV-1 preparations were analyzed by immunoblot, high-pressure liquid chromatography, and protein sequence analyses. These analyses identified several cellular proteins inside HIV-1: elongation factor 1alpha, glyceraldehyde-3-phosphate dehydrogenase, HS-1, phosphatidylethanolamine-binding protein, Pin1, Lck, Nm23-H1, and the C-terminal tail of CD43. Several of these proteins were found as fragments of their full-sized proteins that appear to be generated by our protease treatment of the virions, the HIV-1 protease, or a cellular protease. Recent advances in cell biology and biochemistry have identified some of these proteins as actin-binding proteins. These results support the hypothesis that actin filaments are incorporated into the virion and may provide additional clues for the understanding of the interaction between viral and cellular proteins during assembly and budding.

Actins↗
PubMed2000

Current status of the Maze procedure for the treatment of atrial fibrillation.

Since the first patient underwent the Maze procedure on September 25, 1987, 346 patients have undergone this operation for the treatment of atrial fibrillation. The procedure was designed as an open-heart operation performed through a median sternotomy. It underwent 2 major modifications relatively early in the series, evolving into the so-called Maze-III procedure, which has been used exclusively since April 16, 1992. Since that time, the Maze-III procedure has been adapted to allow it to be done by minimally invasive techniques. In addition, we recently performed the entire procedure in 2 patients without the use of cardiopulmonary bypass. The operative mortality rate has remained at 2% to 3%. This includes patients undergoing concomitant high-risk cardiac surgical procedures and all re-do cases. The overall success rate in curing atrial fibrillation has been 99%. The procedure itself has been shown to cause no permanent damage to the sinus node. The left atrium has been documented to function long-term postoperatively in 93% of patients and the right atrium functions in 99% of patients. The Maze-III procedure remains the surgical procedure of choice for the treatment of medically refractory atrial fibrillation.

Atrial Fibrillation↗
PubMed2000

The Maze-III procedure combined with valve surgery.

Previous studies have suggested that the Maze procedure is not as effective in controlling atrial fibrillation when the arrhythmia is associated with significant valvular heart disease. In this study, we evaluate our own results in 83 patients who underwent 96 valve procedures in combination with the Maze-III procedure. Our results indicate that the Maze-III procedure is just as safe and effective in controlling atrial fibrillation associated with valvular heart disease as it is in controlling atrial fibrillation not associated with valvular heart disease.

Aged↗
PubMed2000

Observations on the perioperative management of patients undergoing the Maze procedure.

In addition to the usual measures that constitute optimal perioperative care after cardiac surgery, the Maze procedure demands several other measures because of certain complications that are unique to this particular operation. These complications include preoperative conditions such as amiodarone therapy, thromboembolism, diastolic dysfunction of the left ventricle, and associated valvular heart disease, as well as intraoperative differences that include multiple atriotomies and excision of both atrial appendages. The most common postoperative complications are atrial arrhythmias, excessive fluid retention, and pulmonary complications. In this article, we outline our own approach to the perioperative care of patients undergoing the Maze procedure.

Atrial Fibrillation↗
PubMed2000

Nsc and Fmoc Nalpha-amino protection for solid-phase peptide synthesis: a parallel study.

The 2-(4-nitrophenylsulfonyl)ethoxycarbonyl (Nsc) group is an alternative to Fmoc for Nalpha-protection in solid-phase peptide synthesis. Nsc-amino acids may be particularly suitable for automatic synthesizers, in which the amino acids are stored in solution, and the incorporation of residues prone to racemization such as Cys and His. Owing to the hydrophilicity of the Nsc group, these derivatives are useful for the preparation of protected peptides in convergent solid-phase peptide synthesis strategies.

Amino Acid Sequence↗
PubMed2000

Surgical correction for lower lid epiblepharon in Asians.

BACKGROUND/AIMS: Epiblepharon is a congenital lid anomaly in which a fold of skin and underlying orbicularis muscle push the lashes against the eyeball. It is important to get a good lash eversion effect without forming a prominent lid crease in Asian patients. The surgical effect of this rotating suture technique was evaluated. METHODS: Surgical correction for epiblepharon was performed on 197 patients and the results analysed in 169 patients who had been followed for 1 month or more. After subciliary incision, several buried 8-0 nylon sutures were placed to allow adhesion between the tarsal plate and the subcutaneous tissue of the upper skin flap with minimal resection of pretarsal orbicularis and redundant skin. RESULTS: 156 patients (92.3%) showed satisfactory results during 7.1 months of average follow up. Reoperation was performed only on two patients out of 13 because of mildness of symptoms and signs. Complications were minimal including suture abscesses in four patients and wound dehiscence in one. CONCLUSION: The rotating suture technique was very effective in repairing epiblepharon without forming a prominent lower eyelid crease.

Adolescent↗
PubMed2000

Vascular hamartoma of the orbit.

The aim of this presentation is to report a combined form of vascular malformation of the orbit. A 2-year-old girl had a four-month history of severe proptosis in the right eye. The patient had intermittent proptosis in association with a common cold. The globe was displaced downward and extraocular motility was markedly limited. Multiple intraconal and some extraconal cysts were removed with transcutaneous transseptal anterior orbitotomy. Histological examination showed several characteristics of vascular anomaly. There were malformatively dilated veins intermingled with dilated lymphatic channels, focal cavernous and capillary hemangiomatous features. This combined form of vascular anomaly can be presented as a venous lymphatic malformation associated with hemangiomatous features.

Child, Preschool↗
PubMed1999

Assay of 2-naphthol in human urine by high-performance liquid chromatography.

This paper describes a novel liquid chromatographic method for the quantitation of 2-naphthol in human urine. Urine samples were extracted after enzymatic hydrolysis of glucuronides and sulfates; 2-naphthol was then separated using reversed-phase high-performance liquid chromatography. The corresponding detection limits were 0.04 ng/ml for the standard sample in acetonitrile and 0.13 ng/ml for urine samples. The level of urinary 2-naphthol in 100 Korean shipyard workers was analyzed using this new method. The level ranged from 0.21 ng/ml (0.26 micromol/mol creatinine) to 34.19 ng/ml (59.11 micromol/mol creatinine), and the mean+/-standard deviation was 5.08 ng/ml (6.60 micromol/mol creatinine)+/-5.75 ng/ml (9.22 micromol/mol creatinine). The mean+/-standard deviation of urinary 2-naphthol level of smokers, 7.03 ng/ml (8.49 micromol/mol creatinine)+/-6.16 ng/ml (10.23 micromol/mol creatinine), was significantly higher than that of non-smokers, 2.49 ng/ml (4.10 micromol/mol creatinine)+/-3.92 ng/ml (7.03 micromol/mol creatinine).

Acetonitriles↗
PubMed1999

123I-IPT brain SPECT study in essential tremor and Parkinson's disease.

OBJECTIVE: To investigate nigral neuronal damage in patients with isolated postural tremor and those with postural and rest tremor without parkinsonism. METHODS: Using [123I]-N-(3-iodopropen-2-yl)-2 -carbomethoxy-3beta-(4-chlorophenyl) tropane SPECT, we measured the basal ganglia-occipital cortex/occipital cortex ([BG-OCC]/OCC) uptake ratios in 21 control subjects and patients with isolated postural tremor (n = 9), postural and rest tremor (n = 6), and PD (n = 11). RESULTS: In the patients with PD, the means (+/-SD) of the (BG-OCC)/OCC ratios of the ipsilateral (2.35+/-0.37) and the contralateral (1.97+/-0.33) sides to the more severely affected limbs were significantly lower than the mean of the bilateral (BG-OCC)/OCC ratios of the age-matched control subjects (3.83+/-0.66). The mean (+/-SD) of the bilateral (BG-OCC)/OCC ratios of the patients with isolated postural tremor (3.60+/-0.83) was comparable with that of the age-matched control subjects. However, the mean (+/-SD) of the bilateral (BG-OCC)/OCC ratios of the patients with postural and rest tremor (2.61+/-0.18) was lower than that of the control subjects (p < 0.05). The mean of the bilateral (BG-OCC)/OCC ratios of the patients with postural and rest tremor was comparable with that of the side ipsilateral to the severely affected limbs of the patients with PD. However, it was higher than that of the side contralateral to the limbs more severely affected by PD. Four of the six patients with postural and rest tremor had (BG-OCC)/OCC ratios lower than 2 standard deviations from the mean of the age-matched control subjects. CONCLUSIONS: Later in their clinical courses, some patients with postural tremor may acquire rest tremor in association with mild substantia nigra neuronal loss.

Adult↗
PubMed1999

Nonanticoagulant heparin prevents coronary endothelial dysfunction after brief ischemia-reperfusion injury in the dog.

BACKGROUND: Coronary endothelial dysfunction after brief ischemia-reperfusion (IR) remains a clinical problem. We investigated the role of heparin and N-acetylheparin, a nonanticoagulant heparin derivative, in modulating coronary endothelial function after IR injury, with an emphasis on defining the role of the nitric oxide (NO)-cGMP pathway in the heparin-mediated effect. METHODS AND RESULTS: Male mongrel dogs were surgically instrumented, and the effects of both bovine heparin and N-acetylheparin on coronary endothelial vasomotor function, expressed as percent change from baseline flow after acetylcholine challenge, were studied after 15 minutes of regional ischemia of the left anterior descending artery (LAD) followed by 120 minutes of reperfusion. In dogs treated with placebo (saline), coronary vasomotor function was significantly (P</=0.03) decreased after 15 and 30 minutes of reperfusion (65+/-12% and 73+/-12%) compared with preischemia (103+/-6%). In contrast, the vasodilatory response to the endothelium-independent vasodilator sodium nitroprusside was maintained during reperfusion. Preischemic administration of both bovine heparin and N-acetylheparin (6.0 mg/kg IV) preserved coronary endothelial function throughout reperfusion. In a parallel group of dogs, nitrate/nitrite (NOx) and cGMP levels in the LAD were measured after treatment and during 15-minute reperfusion. Preischemic administration of N-acetylheparin caused a significant increase in basal NOx and cGMP levels compared with saline controls. Pretreatment with N-acetylheparin also caused a significant increase in NOx and cGMP levels in the LAD after 15 minutes of reperfusion compared with IR alone. CONCLUSIONS: These results suggest that heparin preserves coronary endothelial function after brief IR injury by a mechanism independent of its anticoagulant activity and that the effect of heparin may be mediated in part by activation of the NO-cGMP pathway.

Animals↗
PubMed1999

Role of retinoid receptors in the regulation of mucin gene expression by retinoic acid in human tracheobronchial epithelial cells.

To investigate which retinoid receptors are critical in the regulation by all-trans-retinoic acid (RA) of the mucin genes MUC2, MUC5AC and MUC5B in cultured normal human tracheobronchial epithelial (NHTBE) cells, we used pan-RAR-, pan-RXR- and RAR- isotype (alpha, beta and gamma)-selective agonists and RARalpha- and RARgamma-selective antagonists (RAR is RA receptor and RXR is retinoid X receptor). RAR-, RARalpha- and RARgamma-selective agonists strongly induced mucin mRNAs in a dose-dependent manner, while the RARbeta-selective retinoid only weakly induced mucin gene expression at very high concentrations (1 microM). The pan-RXR-selective agonist by itself did not induce mucin gene expression, but acted synergistically with suboptimal concentrations of the pan-RAR agonist. A retinoid with selective anti-activator-protein-1 activity only marginally induced mucin gene expression. The RARalpha antagonist strongly inhibited mucin gene induction and mucous cell differentiation caused by RA and by the RARalpha- and RARgamma-selective retinoids. In contrast, the RARgamma antagonist only weakly inhibited RARalpha-selective-retinoid-induced mucin gene expression, but completely blocked mucin gene expression induced by the RARgamma-selective retinoid. Our studies indicate that RARalpha is the major retinoid receptor subtype mediating RA-dependent mucin gene expression and mucous cell differentiation, but that the RARgamma isotype can also induce mucin genes. Furthermore these studies suggest that RARbeta is probably not (directly) involved in RA-induced mucin gene expression.

Base Sequence↗
PubMed1999

Expression of p27Kip1 and cyclin D1 proteins is inversely correlated and is associated with poor clinical outcome in human gastric cancer.

BACKGROUND AND OBJECTIVES: p27Kip1 is an inhibitor of cyclin-dependent kinases and is speculated to be a potential prognostic indicator in numerous human cancers. We investigated expression of p27Kip1 along with cyclin D1 in gastric cancer to estimate the clinical utility of p27Kip1. METHODS: Immunohistochemical assay for p27Kip1 and cyclin D1 proteins was performed in 64 patients with primary gastric cancer. Correlation between p27Kip1 expression and clinical-biological parameters including patient survival was analyzed. RESULTS: p27Kip1 expression was suppressed in 40 (62.5%) of 64 gastric cancer patients and cyclin D1 was overexpressed in 22 (34.4%) out of 64. Expression of p27Kip1 was significantly reduced in poorly differentiated cancers (82.1%, 23/28; P = 0.015) and was also reduced in the tumors with high S-phase fraction (86.7%, 26/30) compared with tumors showing low S-phase fraction (41.2%, 14/34; P = 0.0002). Expression of p27Kip1 and cyclin D1 was inversely correlated (P = 0.021). In univariate analysis, extent of the disease (P < 0.001), expression of cyclin D1 (P = 0.0001), and reduced expression of p27Kip1 (P = 0. 0006), were statistically significant to predict patient's outcome, but depth of invasion (P = 0.008) and pathologic stage (P = 0.009) emerged as significant prognostic indicators in multivariate analysis. CONCLUSION: Expression of p27Kip1 is closely linked with cell proliferation and differentiation of human gastric cancer. p27Kip1 seems to have potential as a prognostic marker in the management of gastric cancer patients.

Adult↗
PubMed1999

Comparative studies of Nsc and Fmoc as N(alpha)-protecting groups for SPPS.

2-(4-Nitrophenyl)sulfonylethoxycarbonyl (Nsc) is an alternative base-labile N(alpha)-protecting group to 9-fluorenylmethoxycarbonyl (Fmoc) for amino acids. The UV spectrum of the Nsc group exhibits moderate absorption at 380 nm which is excellent for real-time monitoring of the deprotection process. It also decreases the rearrangement of X-Asp, which can be a serious problem in SPPS.

Amino Acids↗