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Y Kim

Publications and source records attributed to Y Kim.

At least 613 records · Page 34Linked to original sources
PubMed1995

Evaluation of lead exposure in workers at a lead-acid battery factory in Korea: with focus on activity of erythrocyte pyrimidine 5'-nucleotidase (P5N).

OBJECTIVE: To evaluate lead exposure among lead-acid battery workers in Korea, to evaluate in more detail the erythrocyte pyrimidine 5'-nucleotidase (P5N) test for lead exposure, and to evaluate the abnormal accumulation of erythrocyte pyrimidine nucleotides in the battery workers. METHODS: Activity of P5N and other biological variables were examined in 66 exposed workers in a lead-acid battery factory and in 26 non-exposed workers in Korea. RESULTS: At the factory the time-weighted average of 13 (72%) of 18 air samples for lead exceeded 0.05 (range 0.012-0.468) mg/m3. Blood lead concentration (PbB) in 39 of the 66 exposed workers was above 40 micrograms/dl, and the mean (SD) PbB in the exposed group was 45.7 (15.7) micrograms/dl. Compared with the nonexposed group, free erythrocyte protoporphyrin in the exposed group was significantly increased, whereas erythrocyte P5N activity and activity of erythrocyte delta-aminolevulinic acid dehydratase (ALAD) were significantly inhibited. Erythrocyte P5N activity had valid correlation biologically with PbB and with other biological variables, such as ALAD activity. In 28 exposed workers, the concentration of erythrocyte pyrimidine nucleotides (uridine 5'-diphosphate-glucose and cytidine 5'-triphosphate) correlated inversely with P5N activity and positively with PbB. CONCLUSIONS: These findings show that the depression of erythrocyte P5N activity by lead exposure results in the accumulation of erythrocyte pyrimidine nucleotides. In general, the standard analysis of PbB performed in laboratories around the world remains the most useful index of recent exposure. The results indicate that the erythrocyte P5N activity test provides supporting evidence of lead exposure and shows the effect of lead on nucleotide metabolism.

5'-Nucleotidase↗
PubMed1995

Individual differences in relationship between upper airway resistance and ventilation during sleep onset.

Sleep-induced hypoventilation is caused partly by inadequate compensation for elevated upper airway resistance (UAR). Some evidence suggests that the effect of UAR on ventilation may vary among individuals. The relationship between minute ventilation (VI) and UAR was examined in 26 healthy young men (average of 10.12 sleep onsets). Variables were analyzed over transitions between wakefulness (defined by alpha electroencephalographic activity) and sleep (theta electroencephalographic activity). Transitions to sleep were associated with increases in UAR in synchrony with reductions in VI, and equally rapid opposite changes occurred with awakenings. The relationship between the magnitudes of the changes in VI and UAR at transitions varied among subjects, accounting for 30% of the variance for alpha-to-theta transitions and 50% of the variance for theta-to-alpha transitions. Results indicated that, although ventilatory changes during sleep onset are partly a consequence of changes in UAR, alterations in UAR do not account fully for alterations in VI. Other factors that may contribute to ventilatory instability during sleep onset include state-related fluctuations in drive to the primary respiratory muscles and variability in compensatory mechanisms.

Adult↗
PubMed1995

Differential distribution of type IV collagen chains in patients with diabetic nephropathy in non-insulin-dependent diabetes mellitus.

Thickening of the glomerular basement membrane (GBM) and expansion of the mesangial matrix are hallmarks of human diabetic nephropathy. Renal tissues from 15 patients with type II (non-insulin-dependent) diabetes (NIDDM) were studied by immunofluorescence (IF) and immunogold electron microscopy (IEM) for the distribution of 2 type IV collagen peptides [alpha 3(IV) noncollagenous (NC) domain and alpha 4(IV) NC domain] and 2 classical type IV collagen chains [alpha 1(IV) NC domain and alpha 2(IV) domain]. There was intense staining for alpha 3(IV) NC and alpha 4(IV) NC domain in the GBM but not in the mesangial matrix of patients with overt diabetic nephropathy. In contrast, staining with antibodies to alpha 1(IV) NC and alpha 2(IV) NC domain reacted with mesangial matrix but was significantly decreased in the GBM in the patients with overt diabetic nephropathy. IEM confirmed the IF findings. These data suggest that expansion of the mesangial matrix and thickening of GBM in NIDDM involves separate and distinct type IV collagen components and that the site-specific matrix alterations in NIDDM and type I (insulin-dependent) diabetes are parallel.

Adult↗
PubMed1995

Molecular cloning and characterization of the bovine and porcine outer dense fibers cDNA and organization of the bovine gene.

Outer dense fibers (ODF) or accessory fibers are filamentous structures of the sperm tail of many eumetozoan organisms endowed with internal fecundation. The bovine and porcine cDNA of an outer dense fiber protein was cloned, sequenced and compared to the previously characterized human and rat cDNA sequences. The coding sequences and the 5' and 3' untranslated regions of the ODF cDNAs are highly conserved. A comparison of the bovine, porcine, human and rat ODF protein sequences revealed that the protein displays a high degree of similarity, ranging from 87% to 98%. The ODF protein is rich in cysteine and contains the C.X.P. repeat at the C-terminal which is different in number among mammalian species. All the 27 cysteine residues in the ODF sequence except those in the C.X.P. repeat are conserved in the four species. We report here also the organization of the bovine ODF gene which is similar to that of human and rat. The transcription start site in the bovine ODF gene is localized 98 bp upstream of the translation start site. Alignment of the 5' flanking region of bovine ODF with the rat gene reveals that the first 130 nucleotides upstream of the transcription start site exhibit an overall sequence similarity of 83%. This conserved region contains a TATA-like box (TTTAAA) and binding sites for AFT/CREB and EGR-1 transcription factors.

Amino Acid Sequence↗
PubMed1995

Combined pyridostigmine-thyrotrophin-releasing hormone test for the evaluation of hypothalamic somatostatinergic activity in healthy normal men.

Pyridostigmine (PST), a cholinesterase inhibitor, induces a clear growth hormone (GH) release in man by suppression of hypothalamic somatostatin (SRIH). Somatostatin suppresses thyrotrophin (TSH) release in rats and men. Earlier studies showed that the thryotrophin-releasing hormone (TRH)-induced TSH response was not altered by 60-120 mg of PST. We studied whether a larger dose (180 mg) of PST can increase the TSH response to TRH. Six healthy young men were studied with the following six tests: (Test 1) 200 micrograms of TRH i.v.; (Test 2) 180 mg of PST po; (Test 3) three different doses of PST (60, 120, 180 mg) + TRH; (Test 4) 100 micrograms of octreotide (SMS) i.v.; (Test 5) SMS + TRH; (Test 6) PST + SMS + TRH. A large dose of PST (180 mg) significantly augmented GH, TSH and prolactin responses to TRH, while smaller doses of PST (60 and 120 mg) did not significantly increase the responses of GH and TSH. While the increased TRH-induced prolactin response by PST was not suppressed by SMS, the increased responses of GH and TSH were suppressed remarkably by SMS. Most of the subjects noticed a mild to moderate abdominal pain, nausea and muscular fasciculation after the administration of a large dose of PST administration. These data suggest that suppression of hypothalamic SRIH secretion by 180 mg of PST can augment the TSH response to TRH. However, the considerable side effects should be minimized before clinical application of the combined PST-TRH test.

Adult↗
PubMed1995

Structural-functional relationships in Alport syndrome.

Renal morphometric analysis was performed in 15 (13 male) Alport syndrome patients ages 4 to 26 years, along with 10 controls ages 3 to 26 years, to better understand the structural basis of renal dysfunction in Alport syndrome. The glomerular basement membrane (GBM) width class frequencies of controls were normally distributed; those of Alport syndrome patients were slightly skewed, especially toward thicker classes, although there was also an increase in the proportion of thinner classes. Mesangial volume fraction was not different between Alport syndrome patients (0.21 +/- 0.09) and controls (0.19 +/- 0.04). There was an inverse correlation between mesangial volume fraction and creatinine clearance in Alport syndrome patients (r = -0.72, P < 0.01); however, the creatinine clearances in Alport syndrome patients were far less than in insulin-dependent diabetic patients with similar mesangial volume fraction. Similarly, there was no significant difference in the surface density of the peripheral GBM (in square micrometers per cubic micrometer) in Alport syndrome patients (0.12 +/- 0.04) versus controls (0.13 +/- 0.02). The surface density of the peripheral GBM correlated with creatinine clearance in Alport syndrome patients (r = 0.71, P < 0.01). However, there was a greater reduction in creatinine clearance as related to declining the surface density of the peripheral GBM in Alport syndrome than in diabetic patients. The cortical interstitial volume fraction was highly inversely correlated with creatinine clearance in Alport syndrome patients (r = -0.85, P < 0.01). Global glomerular sclerosis was 0% in five and 5 to 61% in nine Alport syndrome patients and correlated inversely with creatinine clearance (r = -0.74, P < 0.01). However, the creatinine clearance was lower in Alport syndrome than in diabetic patients with similar cortical interstitial volume fraction and percent glomerular sclerosis. There was no significant difference in an index of glomerular number between Alport syndrome patients and controls. Thus, changes in mesangial volume fraction, cortical interstitial volume fraction, percent glomerular sclerosis, and surface density of the peripheral GBM in Alport syndrome patients only partially account for the reduction in creatinine clearance. It was speculated that decreased glomerular capillary wall hydraulic conductivity in Alport syndrome could explain many of these observations.

Adolescent↗
PubMed1995

Prevalence of diabetes and IGT in Yonchon County, South Korea.

OBJECTIVE: To determine the prevalence of diabetes and impaired glucose tolerance (IGT) in Yonchon County of South Korea and to investigate their associated factors. RESEARCH DESIGN AND METHODS: We performed a population-based cross-sectional study with random cluster sampling of residents > or = 30 years of age. Among the 3,804 residents sampled, a total of 2,520 participants had a standard 75-g oral glucose tolerance test and answered a detailed questionnaire. We also collected standard anthropometric data. RESULTS: If the data for participants in the age range of 30-64 years were adjusted to the standard world population, the prevalence of diabetes was 7.2% and the prevalence of IGT was 8.9%. It was observed that the significant factors associated with diabetes were waist-to-hip circumference ratio, serum triglyceride levels, age, systolic blood pressure, family history of diabetes, and locality. CONCLUSIONS: The prevalence of diabetes in Yonchon County was substantially higher than was previously suggested. The risk of diabetes increased with the increased central obesity and metabolic disturbances associated with insulin resistance.

Adult↗
PubMed1995

Glucose-induced alteration of integrin expression and function in cultured human mesangial cells.

Alteration in mesangial volume, due to an increase of the matrix surrounding mesangial cells, is a hallmark indicator of nephropathy in diabetes. Mesangial cells may also play a significant role in the development of nephropathy. Therefore, we examined the effect of glucose on the expression of integrins by cultured human mesangial cells and their ability to interact with collagen IV, a major component of the mesangial matrix. Human mesangial cells were grown in 5 and 25 mM glucose and their integrin profile was examined by immunoprecipitation and flow cytometry in each experimental condition. The results indicate that when mesangial cells were grown in 25 mM glucose, the expression of integrin subunit alpha 2, was increased, while the alpha 1 subunit was considerably decreased, as compared to cells grown in 5 mM glucose. Additionally, mesangial cells were tested for their ability to adhere to collagen IV in a solid-phase assay in the presence of neutralizing antibodies to integrin subunits. The results of these experiments indicate that both alpha 1 and alpha 2 complexed to beta 1 (alpha 2 beta 1 and alpha 1 beta 1) are major mesangial cell receptors for adhesion to collagen IV both in 5 and 25 mM glucose. The two receptors act in concert to mediate adhesion of mesangial cells to type IV collagen. When cell surface expression of the alpha 1 subunit in 25 mM glucose was reduced, the alpha 2 subunit was involved in adhesion to a greater extent than it was in 5 mM glucose. Immunoperoxidase histochemical studies localized both alpha 1 and alpha 2 integrin subunits in the mesangium of normal adult kidneys, suggesting that in vivo interaction with collagen IV could involve both of these receptors. These observations suggest that glucose-induced alterations in integrin expression may modify the ability of mesangial cells to interact with collagen IV.

Antibodies, Monoclonal↗
PubMed1995

A new technique for pancreaticogastrointestinal anastomosis without suturing the pancreatic parenchyma.

BACKGROUND: In an attempt to lessen the incidence of pancreatic fistula and the disruption of pancreatic anastomosis after pancreatoduodenectomy, we have developed a new technique for pancreaticogastrointestinal anastomosis that consists of pancreatectomy using the ultrasonic dissector and implantation of the pancreatic duct into the gastrointestinal tract without suturing the pancreatic parenchyma. The purpose of this study is to evaluate the safety and reliability of this new technique in a canine model of pancreaticogastrostomy and pancreaticoduodenostomy using 10 beagle dogs. STUDY DESIGN: Canine pancreas was resected using the ultrasonic dissector. In the distal pancreas, a 1-cm long stump of the main pancreatic duct was freed and the other smaller pancreatic ducts were skeletonized and securely ligated. The main pancreatic duct was implanted into the stomach or the duodenum and fixed to the seromuscular layer with purse-string sutures without suturing the pancreatic parenchyma. RESULTS: There was no anastomotic leakage, signs of peritonitis, or abscess formation, and the pancreas was grossly normal in appearance seven days after operation. Histologic examination of the specimens harvested 30 days after operation revealed good connective tissue union between the pancreas and the gastric or duodenal wall, and good mucosal continuity between the pancreatic duct and the stomach or duodenum. CONCLUSIONS: This new technique is simple, safe, and reliable, and is recommended as an alternative method for restoring pancreaticogastrointestinal continuity after pancreatoduodenectomy.

Anastomosis, Surgical↗
PubMed1995

p53 gene status in endometrial carcinomas showing diffuse positivity for p53 protein by immunohistochemical analysis.

Although detection of p53 protein by immunohistochemical testing was originally thought to indicate p53 gene mutation, recent analyses of human malignancies have shown that high expression of p53 protein may occur without detectable gene mutation. Several explanations have been proposed for this phenomenon, including mutation out of "hot spot" regions, overexpression of wild-type protein, sampling error in molecular analyses, and conformational changes of wild-type p53 protein. As discussed, it is unlikely that the first two possibilities contribute significantly to the occurrence of this phenomenon, and the current study examined the possibility that sampling error in molecular analyses might account for a lack of concordance between immunohistochemical and molecular analyses. Such a possibility exists because immunohistochemical studies frequently report high expression when staining is only focal or regional and molecular analyses are based on the polymerase chain reaction, which is highly exponential in nature and may not detect mutation if the target gene segment is not amplified early in the chain reaction. In the current report, p53 protein expression was examined by immunohistochemical testing in 45 cases of endometrioid carcinoma, and all cases showing diffuse positivity were then examined by polymerase chain reaction in combination with single-strand conformational analysis for exons 4 to 9 with the use of a microdissection technique to separate malignant from benign cells. Of the 45 cases, diffuse staining was found in four cases, and only two of the four were found to show evidence of gene mutation.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence↗
PubMed1995

[Metabolic fate of porphyrin and its precursors in porphyria and porphyrinuria].

The metabolic fate of porphyrins and its precursors in porphyria and porphyrinuria is discussed to understand their excretion into the feces or urine. Eight enzymes play important roles in the porphyrin pathway. An enzymatic defect at each step of heme synthesis will induce each typical form of porphyria with the exception of the first enzyme. Each porphyria is described according to the enzyme in the heme biosynthetic sequence. Lead, which disturbs two enzymes involved in the heme biosynthesis, is one of typical chemicals inducing porphyrinuria. Lead porphyrinuria is also described according to the enzymes in the pathway. The figure of porphyrin pathway, drawn in details in the present chapter, will make it easier to understand the heme biosynthetic pathway related to porphyria or porphyrinuria.

Aminolevulinic Acid↗
PubMed1995

HPLC preparation of highly purified single-stranded M13 DNA.

Closed-circular, single-stranded viral DNAs are widely employed in DNA cloning and sequencing experiments. Because of their well-defined structure and sequence, closed-circular, single-stranded DNAs have also been used for ligand binding experiments and light scattering measurements. However, there is a high molecular weight impurity observed in light scattering experiments, which sometimes contaminates single-stranded DNA purified from phage that has been precipitated in polyethylene glycol, average molecular weight 8000, and purified by standard phenol-chloroform extraction. Three methods have been examined that remove this impurity from closed-circular, single-stranded M13mp19 DNA (SS M13 DNA). One employs a commercial peparation. This procedure yields pure but degraded SS M13 DNA, as shown by light scattering measurements and HPLC. Another employs a Whatman DE52 (diethylamino cellulose) column. This procedure yields intact DNA, but in poor yield (less than 20% of that obtained by phenol-chloroform extraction). The last was the most successful. This employs HPLC with a Waters AP-1 column with DEAE 8HR bedding. This procedure, which provides DNA in high yield (80%-90% column recovery) with an intact structure, is an efficient method for the isolation of high-purity, closed-circular, single-stranded viral DNA suitable for physical investigations and ligand binding measurements.

Artifacts↗
PubMed1995

Altered expression of matrix metalloproteinase-2, TIMP, and TIMP-2 in obstructive nephropathy.

We have previously characterized the evolution of renal cortical interstitial fibrosis in the rabbit model of unilateral ureteral obstruction (UUO). In our earlier report, we examined the extracellular matrix protein composition of the interstitial space. Of note, UUO was associated with the acquisition of prominent interstitial collagen IV immunoreactivity. Interstitial collagens I and III were also increased. In situ hybridization localized increased expression of collagens I and IV to cells of the interstitial space. In the current study, we examine metalloproteinase and metalloproteinase inhibitor expression in the obstructed renal cortex. Matrix metalloproteinase-2 is a metalloproteinase with activity against both collagen IV and denatured collagen I. At day 3 of UUO, both transcripts were significantly increased, although expression of these mRNAs was not different from controls after 7 and 16 days of UUO. Expression of mRNA of tissue inhibitor of the metalloproteinases (TIMP) was significantly increased in the UUO samples at all times, although it was maximal at day 3. Immunohistochemically, increased TIMP reactivity localized to the interstitial space, and TIMP mRNA expression was seen to parallel the interstitial macrophage infiltration that accompanies ureteteral obstruction. In contrast, TIMP-2 mRNA expression appeared to be biphasic, with peaks at both day 3 and day 16 of UUO. At day 7, expression was not different from controls. These data suggest a role for impaired matrix degradation in the development of interstitial fibrosis in the obstructed kidney, particularly at late times when collagen mRNA expression has returned to control values.

Animals↗
PubMed1995

An echocardiographic study of interactions between pindolol and epinephrine contained in a local anesthetic solution.

An increasing number of dental patients are taking beta-adrenergic blockers for the treatment of hypertension or angina pectoris. If epinephrine-containing local anesthetics are administered to such patients, interactions between epinephrine and the beta-blocking agent may induce cardiovascular complications. We assessed in volunteers the effects of intraoral injection with 2% lidocaine containing 1:80,000 epinephrine (L-E) on cardiac function after pretreatment with the beta-blocking agent pindolol. M-Mode echocardiography was used for the assessment. The injection of L-E after administration of pindolol did not alter cardiac preload, whereas it reduced the stroke volume, due to an increase in afterload and a decrease in myocardial contractility. Reductions in stroke volume and heart rate led to a decrease in cardiac output. Because total peripheral vascular resistance increased markedly, blood pressure was elevated despite the reduced cardiac output. These results suggest that cardiac function of dental patients on beta-blocker therapy can be adversely affected by epinephrine-containing local anesthetics. Therefore, when such an anesthetic solution has to be used in patients on beta-blocker therapy, careful systemic monitoring is needed.

Adrenergic beta-Antagonists↗
PubMed1995

The incidence of arrhythmias during induction of general anesthesia.

In this study, our induction methods of endotracheal anesthesia was evaluated with reference to electrocardiogram, hemodynamic status and arterial blood gas analysis on 153 patients. From the beginning of induction, electrocardiogram was recorded continuously to the completion of intubation. The blood pressure and heart rate were also measured. Arterial blood samples were taken at 40 seconds of apneic period after the mask was removed from the patient's face (CONT group), at 40 seconds of apnea with intratracheal spray (LIDO group), and after intubation following intratracheal spray (INT group). In the electrocardiographic survey, arrhythmias during intubation were rare (1/113, 0.9%). PaCO2 values in INT group showed a significant elevation (+ 14.0 mmHg; p < 0.01) compared to these in CONT group. As a result of careful and gentle induction techniques, the incidence of arrhythmias during intubation was very low. However, an elevation of PaCO2 was not avoidable, even in smooth and successful intubation. In conclusion, the importance of more adequate ventilation coupled with skillful intubation in a shorter period to avoid hypercapnia and arrhythmias is appreciated again in the endotracheal anesthesia for the maxillofacial surgical patients with anatomical airway problems.

Adult↗