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Biomedical subjects

M H Kim

Publications and source records attributed to M H Kim.

At least 145 records · Page 8Linked to original sources
PubMed1999

Inflammatory pseudotumor of the liver in patients with recurrent pyogenic cholangitis: CT-histopathologic correlation.

PURPOSE: To correlate computed tomographic (CT) features of inflammatory pseudotumors of the liver with histopathologic results in patients with recurrent pyogenic cholangitis. MATERIALS AND METHODS: CT features of 13 cases of inflammatory hepatic pseudotumor in 10 patients with recurrent pyogenic cholangitis were reviewed. Diagnosis was made by means of surgical resection in all patients. CT scans were analyzed for the appearance of masses and ancillary findings in correlation with the histopathologic findings in each resected specimen. RESULTS: The masses were 2.0-7.0 cm (mean, 3.5 cm). At nonenhanced CT, the masses appeared as ill-defined, hypoattenuating lesions. At contrast material-enhanced CT, the masses exhibited central hypoattenuating areas with an iso- or hyperattenuating thickened periphery in four cases and a multiseptate appearance with hyperattenuating internal septa and periphery in nine cases. CT-histopathologic correlation showed that the central hypoattenuating area indicated the presence of chronic inflammatory infiltrates with foamy histiocytes, plasmacytes, and lymphocytes, while iso- or hyperattenuating areas in the periphery and internal septa of the mass represented fibroblastic proliferation. All patients had CT features of recurrent pyogenic cholangitis, such as hepatolithiasis, intrahepatic duct stricture and dilatation, common bile duct calculi, pneumobilia, or parenchymal atrophy. CONCLUSION: Although CT features are not specific, inflammatory pseudotumor should be included in the differential diagnosis in patients with recurrent pyogenic cholangitis and a hepatic mass detected at CT.

Adult↗
PubMed1999

Factors relating to readmission of term and near-term neonates in the first two weeks of life. Early Discharge Survey Group of the Health Professional Advisory Board of the Greater New York Chapter of the March of Dimes.

AIMS: A multisite study of term and near term infants readmitted in the first two weeks of life to 9 New York City area hospitals in 1995 was conducted to evaluate factors related to readmission, including length of newborn stay. RESULTS: Of the 30,884 infants born at the 9 study hospitals 391 newborns were readmitted. The major admission diagnoses were infection, 40.7%, hyperbilirubinemia, 39.1%, and feeding and/or gastrointestinal problems, 10.5%. In the first week, 65.1% of readmissions were for hyperbilirubinemia and 19.1% were for infection or suspected sepsis. In the second week, 67.8% of readmissions were for infection and 7.6% were for hyperbilirubinemia. Hyperbilirubinemia was the most frequent diagnosis for White and Asian infants, while infection was most frequent for African-American and Hispanic infants. Age at readmission was younger and the interval from discharge was shorter for infants with hyperbilirubinemia. Abnormalities which should have precluded early discharge included feeding difficulties, cyanotic congenital heart defects, hemolytic disease of the newborn, early jaundice or early high bilirubin levels. CONCLUSION: Attention to identification of infants at risk and programs such as lactation counseling and universal screening for bilirubin (with appropriate interpretation) prior to discharge could have reduced the necessity for readmission regardless of the newborn length of stay.

Adolescent↗
PubMed1999

Intraspinal epidermoid cyst occurring 15 years after lipomyelomeningocele repair. Case report.

The authors report the case of a spinal epidermoid cyst that developed in a patient who had undergone surgery for lipomyelomeningocele repair 15 years earlier. The patient presented with symptoms of retethering. Magnetic resonance imaging revealed a cystic intraspinal mass that extended from L-2 to L-5. The mass proved to be an epidermoid cyst. Spinal epidermoid cysts can cause retethering after a repair of lipomyelomeningocele, and the risk of this development can be present for decades.

Adult↗
PubMed1999

The role of endoscopic fenestration procedures for cerebral arachnoid cysts.

Recently, endoscopic procedures have been recommended as the first surgical option for cerebral arachnoid cyst (AC). The author reports seven ACs treated endoscopically and discuss the role of endoscopic fenestration. The age of the patients ranged from two to 62 years. Three ACs were located in the posterior cranial fossa, two in the suprasellar area, one in the middle cranial fossa, and one in the convexity. All cases were examined by cine magnetic resonance (MR) flow study. The patient's symptoms included headache, vomiting, dizziness, problems in balance, visual disturbance, and seizure. The author performed a cysto-cisternostomy or cysto-ventriculostomy via a single burr hole. The follow-up periods ranged from six to 18 months. There was no mortality or morbidity except one case of intracisternal bleeding during endoscopic procedure. Symptoms were relieved in all seven patients. Follow-up imaging studies revealed a decrease in the size or disappearance of the cysts. The results support that the minimal fenestration procedure as possibly as preserving the internal environment is valuable for the management of ACs.

Adolescent↗
PubMed1999

Choledochal cyst associated the with anomalous union of pancreaticobiliary duct (AUPBD) has a more grave clinical course than choledochal cyst alone.

OBJECTIVE: Since choledochal cyst is frequently associated with the anomalous union of pancreaticobiliary duct (AUPBD), AUPBD has been regarded to be the etiologic factor of choledochal cyst. However, the clinical significance of AUPBD an patients with choledochal cyst has not been clearly defined. Therefore, to clarify the significance of AUPBD in choledochal cyst patients, we compared the clinical features of patients with choledochal cyst according to the presence or absence of AUPBD. METHODS: Among 52 cases which were diagnosed as choledochal cyst out of 5,037 ERCP referrals between August 1990 and December 1996, we selected 44 cases, in which the pancreaticobiliary junction was clearly visualized on cholangio-pancreaticography. These cases were divided into AUPBD-present group (n = 28) and AUPBD-absent group (n = 16). Clinical features were compared between the two groups. Furthermore, in AUPBD-present group, clinical data were also analyzed according to Kimura's classification of AUPBD. RESULTS: In our study, AUPBD was associated with choledochal cyst in 28 (64%) cases. AUPBD was found only in type I and IV according to Todani's classification of choledochal cyst. There were no significant differences between the AUPBD-present group and the AUPBD-absent group in the incidence of gallstone disease, while the incidence of acute inflammation was 93% (26/28) in the AUPBD-absent group (p < 0.01). Carcinoma developed only in the AUOBD-present group (9/28, 32%) (p < 0.05). Pancreatic disorders (i.e. pancreatic stone, pancreatitis or pancreatic cancer) occurred in 12 of 28 cases in the AUPBD-present group (43%), while only in 1 of 16 cases in the AUPBD-absent group (6%) (p < 0.05). CONCLUSION: AUPBD associated with choledochal cyst may have implications not only as a possible etiologic factor but also as an important factor that may affect the clinical course, surgical planning and prognosis. In cases with choledochal cyst, we should make an effort to evaluate the presence of AUPBD.

Adolescent↗
PubMed1999

C677T mutation of the methylenetetrahydrofolate reductase gene among the Korean infants in Seoul city.

The missense mutation, C677T (Ala--->Val), in the methylenetetrahydrofolate reductase (MTHFR) gene, is related to hyperhomocysteinemia and is regarded as a risk factor for coronary artery disease and neural tube defects. The prevalence of this mutation was reported to differ among various ethnic groups, but there are few reports concerning Asian populations. We have investigated the frequencies of C677T mutation in 124 Korean infants (residents in Seoul city, Korea) and 115 Japanese adults (residents in Kobe city, Japan), and compared them with the reported data from other ethnic groups. The frequencies of the three genotypes in Koreans were as follows: C/C (wild homozygosity) 0.27, C/T (heterozygosity) 0.66, T/T (mutated homozygosity) 0.07, while those in Japanese were as follows: C/C 0.44, C/T 0.40, T/T 0.16. There was a marked difference in the genotype frequencies between the two populations (chi-square = 16.67, P = 0.0002), even though they are closely related in genetic background. The high C/T genotype frequency led to significant deviation from Hardy-Weinberg equilibrium (chi-square = 17.35, P = 0.00003). Deviation from Hardy-Weinberg equilibrium has not been found in any other ethnic groups. The high frequency of C/T genotype may offer Koreans a selective advantage.

Adult↗
PubMed1998

Two metal-binding sites in a lead ribozyme bound to competitively by Pb2+ and Mg2+--induced structural changes as revealed by NMR.

We reported recently that a lead ribozyme with modified bases cleaved at an additional site at high Pb2+ concentrations (>0.1 mM), and that the cleavage at a canonical site was enhanced nearly fourfold at the optimum combination of Pb2+ and Mg2+ concentrations [Kim, M. H., Katahira, M., Sugiyama, T. & Uesugi, S. (1997) J. Biochem. (Tokyo) 122, 1062-1067]. Here we have identified two metal-binding sites (sites 1 and 2) of the lead ribozyme at the residue level by NMR. Both sites are located in an asymmetric internal loop of the lead ribozyme. Site 1 is composed of residues of an enzyme strand and site 2 of residues of a substrate strand. The two sites are bound to competitively by Pb2+ and Mg2+. It was revealed that at certain Pb2+ and Mg2+ concentrations, site 1 is occupied by Pb2+ and site 2 is occupied by Mg2+. The dependency of the cleavage at the canonical and other sites on the Pb2+ and Mg2+ concentrations is interpreted by considering the species of metal ions bound to the two sites. It is suggested that the addition of the two metal ions produces similar and different effects on the structure of the lead ribozyme, and the two metal ions have a synergistic effect on the structure.

Binding Sites↗
PubMed1998

Cloning and sequencing of a cyclodextrin glycosyltransferase gene from Brevibacillus brevis CD162 and its expression in Escherichia coli.

A cyclodextrin glycosyltransferase (CGTase) gene of Brevibacillus brevis CD162 was cloned into Escherichia coli using pUC19 as a vector. Determination of the nucleotide sequence showed the presence of an open reading frame of 2079 bp encoding a polypeptide of 693 amino acid residues, composed of a 20-amino acid signal sequence and a 673-amino acid mature enzyme. Neither a TATA- nor a TTGA-like sequence was observed within the cloned DNA fragment. However, the fragment was expressed in Escherichia coli by the lac promoter of pUC19 and 74% of the total activity was secreted into the fermentation medium. The amino acid sequence of the mature CGTase showed the highest homology of 86% to that of Bacillus sp. KC201. The CGTase purified to homogeneity from the recombinant E. coli exhibited the same properties as those of native CGTase from Brevibacillus brevis CD162 in terms of molecular mass, reaction conditions, stability and the production of cyclodextrins.

Amino Acid Sequence↗
PubMed1998

Isolation and characterization of a pufferfish MLL (mixed lineage leukemia)-like gene (fMll) reveals evolutionary conservation in vertebrate genes related to Drosophila trithorax.

The MLL gene is interrupted and fused to a number of partner genes as a result of chromosomal translocations in human leukemias. MLL is a very large protein with a unique domain structure and large regions of homology to Drosophila trx. To define the key structural and functional domains of the MLL protein in vertebrates, we have cloned the genomic region encoding an MLL-like gene in the compact model vertebrate genome of Fugu rubripes. While the similarity between the mouse and human MLL proteins is very high, a lower overall similarity is present between the Fugu and mammalian proteins. Several new highly conserved regions were identified in the portion of the protein included in the MLL leukemia-associated fusion proteins. The conserved nature of regions of similarity between vertebrate forms of MLL and the Drosophila TRX proteins, as well as other domains previously suggested to have a functional role in MLL (including the AT hooks and the DNA methyltransferase domain), was also observed. Therefore, strong evolutionary constraints limited sequence divergence within these domains. The information derived from this comparative analysis will form the basis for the functional study of the MLL protein, particularly as it relates to human leukemogenesis.

Amino Acid Sequence↗
PubMed1998

Cine MR CSF flow study in hydrocephalus: what are the valuable parameters?

To evaluate the changes of intracranial cerebrospinal fluid (CSF) dynamics in hydrocephalus, we studied the various parameters of cine phase contrast (PC) magnetic resonance (MR) CSF flow images in cases of acutely progressive hydrocephalus, comparing them with those in normal CSF circulation. The MR images were obtained with 1.5 T unit using the 2 dimensional cine PC sequence with cardiac gating in 10 non-obstructive hydrocephalus (NOH), 3 obstructive hydrocephalus (OH), and 10 controls. The temporal velocity information from the anterior and posterior cervical pericord spaces, third and fourth ventricles, and aqueduct were plotted as wave form. The wave forms were analyzed for configurations, amplitude parameters (Smax, Smin, Sdif), and temporal parameters (R-S, R-SMV, R-D, R-DMV). The statistical significance of each parameter was examined with paired t-test. All patients with OH underwent endoscopic thrid ventriculostomy, whereas all NOH underwent shunting procedures. In 5 ROIs, distinct reproducible configuration features were obtained at aqueductal and cervical pericord spaces. Statistically significant differences between control and hydrocephalus only in temporal parameters were determined. In NOH, the graph showed R-DMV shortening (p < 0.01) at anterior cervical pericord space. In OH, there were R-DMV shortening (p < 0.05) at anterior cervical pericord space, R-SMV shortening (p < 0.02) at posterior cervical pericord space. Also the level of obstructions could be determined in all OHs. The analysis of MR CSF flow images may give us valuable information on the site of obstruction, explaining the cause of hydrocephalus, thus deciding the necessity of shunting procedures using in vivo images.

Adolescent↗
PubMed1998

Pharmacokinetics of propentofylline and the quantitation of its metabolite hydroxypropentofylline in human volunteers.

Propentofylline (PPF, 3-methyl-1-(5-oxohexyl)-7-propylxanthine) has been reported to be effective for the treatment of both vascular dementia and dementia of the Alzheimer type. The pharmacological effects of PPF may be exerted via the stimulation of nerve growth factor, increased cerebral blood flow, and inhibition of adenosine uptake. The objectives of this experiment are to determine the kinetic behavior of PPF, to identify, and to quantify its metabolite in human. Blood samples were obtained from human volunteers following oral administration of 200 mg of PPF tablets. For the identification and quantification of the metabolite, 3-methyl-1-(5-hydroxyhexyl)-7-propylxanthine (PPFOH), PPFOH was synthesized and identified by gas chromatography/mass spectroscopy (GC/MS) and 1H-nuclear magnetic resonance spectroscopy. The molecular weight of synthesized metabolite is 308 dalton. The PPF and PPFOH in plasma were extracted with diethyl ether and identified by electron impact GC/MS. The plasma concentrations of PPF and PPFOH were determined by gas chromatography/nitrogen phosphorus detector in plasma and their pharmacokinetic parameters were determined. The mean half-life of PPF was 0.74 hr. The areas under the curve (AUCs) of PPF and PPFOH were 508 and 460 ng.hr/ml, respectively. Cmax of PPF was about 828.4 ng/ml and the peak concentration was achieved at about 2.2 hr (Tmax). These results indicate that PPF is rapidly disappeared from blood due to extensive metabolism into PPFOH.

Administration, Oral↗
PubMed1998

US findings of xanthogranulomatous cholecystitis.

The ultrasound (US) scans of eleven patients with histologically proven xanthogranulomatous cholecystitis have been reviewed. The thickness of the gallbladder (GB) wall, echogenicity of the thickened GB wall, the presence of intramural nodules, gallstones, pericholecystic fluid, loss of wall definition with the liver, and intrahepatic ductal dilatation were specifically assessed by two radiologists. The range of thickness of the GB wall was 3-20mm (mean, 11.2 mm). Thickening was diffuse in nine cases and focal in two. The thickened GB wall, excluding intramural nodules, was echogenic in seven, isoechoic in three and hypoechoic in one, compared with hepatic echogenicity. Intramural nodules were found in eight cases. These were discrete, oval or flat, and of low echogenicity. These ranged in size from 6 to 12 mm (mean, 10.5 mm). Gallstones were present in six cases and there was intrahepatic duct dilatation in two of these. Definition between the liver and the GB was obliterated in seven cases. One case of GB perforation, confirmed at operation, demonstrated pre-operatively a GB wall defect and connection with the surrounding pericholecystic fluid. Pericholecystic fluid was absent in the other 10 cases. Xanthogranulomatous cholecystitis presents ultrasonically as GB wall thickening, and the majority of cases in this series also demonstrated intramural hypoechoic nodules. These findings can be helpful in the diagnosis of xanthogranulomatous cholecystitis.

Adult↗
PubMed1998

Dimeric inhibin: a direct marker of ovarian aging.

OBJECTIVE: To investigate whether luteal secretion of inhibin-a is altered in the perimenopausal transition and to evaluate whether luteal inhibin secretion is correlated with other markers of ovarian reserve such as FSH and inhibin-b. DESIGN: Prospective study. SETTING: Reproductive Endocrinology Laboratories at The Ohio State University. PATIENT(S): Twenty-five women 39-52 years of age with regular menstrual cycles. INTERVENTION(S): Daily urine samples were monitored (LH predictor kit) to identify the day of ovulation. Blood samples obtained on days 6 and 8 after the LH surge and on day 3 of the subsequent follicular phase were assayed for FSH, E2, progesterone. inhibin-a, and inhibin-b. MAIN OUTCOME MEASURE(S): Serum levels of inhibin-a, inhibin-b, FSH, E2, and progesterone. RESULT(S): Luteal phase inhibin-a and follicular phase inhibin-b were correlated inversely with age in perimenopausal women. In addition, luteal phase inhibin-a and follicular phase inhibin-b levels were correlated inversely with follicular phase FSH levels. CONCLUSION(S): Both luteal phase inhibin-a and follicular phase inhibin-b levels are correlated inversely with age during the fifth decade of life. These findings suggest that corpus luteum function is altered during the perimenopausal transition. Moreover, these direct measures of ovarian function may be more sensitive indicators of "ovarian reserve" than indirect indicators such as pituitary FSH secretion.

Adult↗
PubMed1998

Effects of ovarian source, patient age, and menstrual cycle phase on in vitro maturation of immature human oocytes.

OBJECTIVE: To determine the efficiency of in vitro maturation, expressed by nuclear maturation, of oocytes aspirated during gynecologic surgeries or collected from excised ovaries. To assess the effect of patient age and cycle phase at collection on the oocyte's ability to mature in vitro. To examine the time course of oocyte maturation in vitro. DESIGN: Nuclear maturation based on patient criteria compared. SETTING: University-based IVF program and research center. PATIENT(S): Consented patients undergoing gynecologic surgeries or patients undergoing oophorectomy. INTERVENTION(S): Oocytes were maintained in culture for 48 hours and evaluated for maturation. MAIN OUTCOME MEASURE(S): Nuclear maturation evaluated as germinal vesicle breakdown (GVBD) or progression to the metaphase II (MII) stage. RESULT(S): A significantly higher percentage of oocytes collected during the follicular phase of the menstrual cycle underwent GVBD than did oocytes collected during the luteal phase (60% versus 48%, respectively). The percentage of oocytes reaching the MII stage, from these two groups, was not different. No statistically significant differences in maturation were observed in oocytes from different ovarian sources or from patients >40 or <40 years of age. CONCLUSION(S): These data suggest that oocytes collected during the follicular phase are more likely to undergo GVBD than oocytes collected during the luteal phase. In this study, ovarian source, age, or cycle phase did not influence the final meiotic maturation of oocytes to metaphase II.

Adult↗