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N H Cho

Publications and source records attributed to N H Cho.

At least 37 records · Page 2Linked to original sources
PubMed1998

Novel mucosal immunization with polysaccharide-protein conjugates entrapped in alginate microspheres.

A novel mucosal immunization was examined using biocompatible and biodegradable alginate microspheres containing a conjugate of polysaccharide antigen and cholera toxin B subunit (CTB). In order to prepare the alginate microspheres with diameters of less than 5 microm, a new diffusion-controlled interfacial gelation technique was developed. Also, in order to improve the mucosal immune response, a pneumococcal capsular polysaccharide type 19 (PS19) was conjugated to the CTB (PS19-CTB). This conjugate was subsequently encapsulated into the alginate microspheres. The loading content of PS19-CTB to the alginate microspheres was 60%. An in vitro sustained release pattern was observed with the antigen-loaded microspheres, showing 80% antigen release within one day. Mucosal and systemic immunities following oral immunization with the alginate microspheres were studied. Balb/c mice were immunized perorally three times at intervals of two weeks. Peroral immunization with 25 microg of PS19-CTB entrapped in the alginate microspheres evoked both the mucosal IgA and systemic IgM responses to PS19 in small intestine and in sera, respectively. The results suggest that both the mucosal and systemic antibody responses could be induced by oral administration of the PS19-CTB antigen entrapped in alginate microspheres.

Alginates↗
PubMed1998

Underexpression of cyclin-dependent kinase (CDK) inhibitors in cervical carcinoma.

Recent studies have revealed a new family of tumor suppressor genes that directly implicate aberrant cell cycle regulation in tumorigenesis. The general function of these gene products is that they prevent cell cycle progression by directly interfering with cyclin/cyclin-dependent kinase (CDK) activation. The importance of these genes is that they are potent inhibitors of CDK. Among these cell cycle inhibitors, p21(WAF1/CIP1) and p16 have been thoroughly studied. However, the role of p21(WAF1/CIP1) and p16 in the tumorigenesis of the uterine cervix has been poorly defined. We used immunohistochemical techniques to study the expression of these cell cycle inhibitors in formalin-fixed, paraffin-embedded cervical tissue to explore the relationship between cyclin/CDK inhibitors and cervical carcinoma. Cervical tissues were analyzed from 46 patients with cervical carcinoma, 30 cases with cervical intraepithelial neoplasia (CIN) and 22 control cases who underwent hysterectomy due to benign gynecologic disease at Yonsei University College of Medicine. All CDK inhibitors were strongly expressed in the reverse cell hyperplasia and koilocytes, whereas they revealed significantly decreased expression in neoplastic tissues (P < 0.05). P16 revealed higher expressions in cases associated with human papillomavirus (HPV) (t test, P < 0.05) than in cases lacking any type of HPV. Our results were consistent with the concept that underexpression of CDK inhibitors may play an important role in neoplastic transformation in cervical carcinoma.

Adult↗
PubMed1998

Short stature in Korean women: a contribution to the multifactorial predisposition to gestational diabetes mellitus.

We examined the associations between demographic characteristics including short stature and the prevalence of gestational diabetes mellitus (GDM) in Korean women. In this study, a total of 9005 pregnant women underwent universal screening for GDM. Oral glucose tolerance tests (100 g OGTT) were performed in positive screenees (1 h plasma glucose > or = 7.2 mmol/l) and GDM was diagnosed using National Diabetes Data Group criteria. Women with GDM were older and heavier than those with a positive screen and normal OGTT, as well as those with a negative screen. However, height of women with GDM was significantly shorter than those with a positive screen and normal OGTT, and a negative screen. When the study subjects were stratified according to height quartiles, the plasma glucose at the screening test decreased as height increased. Furthermore, the prevalence of GDM was highest in the shortest quartile (< or = 157 cm) group; the odds ratio for GDM was two times greater compared with the highest quartile (> or = 163 cm) group, even after controlling for age and body mass index (BMI). In addition, multiple logistic regression analysis revealed that greater prepregnancy BMI, age, weight gain, a parental history of diabetes mellitus, and shorter maternal height were directly and independently associated with the prevalence of GDM. We have found that short stature is an independent risk factor for GDM in the racially homogeneous population of Seoul, Korea. It is suggested that this propensity may be conveyed primarily by environmental influences. However, genetic factors may also modify the response to the environmental insult. Our findings also emphasize the heterogeneity of factors which predispose to GDM.

Adult↗
PubMed1998

Detection of human papillomavirus in warty carcinoma of the uterine cervix: comparison of immunohistochemistry, in situ hybridization and in situ polymerase chain reaction methods.

Warty carcinoma of the uterine cervix is a very rare specific variant of invasive squamous cell carcinoma, usually described as a hybrid feature of condyloma with invasive squamous cell carcinoma. Besides having the koilocytes and maturation of squamous epithelium, there is unequivocal stromal invasion. The feathery surface seems to be characteristic of warty carcinoma, differentiating it from condylomata acuminata or verrucous carcinoma. Using in situ polymerase chain reaction (IS-PCR) and in situ hybridization (ISH) as well as an immunohistochemical technique (IHC), we determined the amplification and expression of several human papilloma virus (HPV) types (6, 11, 33, 16 and 18) in nine warty carcinomas of the uterine cervix. We found amplified HPV predominantly in the nuclei of the feathery surface in all cases only when IS-PCR was applied, while it was detected only in five (55.6%) or six cases (66.7%) by conventional IHC or ISH, respectively. We found multiple types in the same lesion in six cases (66.7%) by IS-PCR, in comparison with ISH which detected a lower incidence (22.2%). This finding of coinfection is more consistent with that seen in low-grade squamous intraepithelial lesions (LSILs) of the uterine cervix than in high SIL. It is important to be aware of these distinct lesions in postmenopausal women with their characteristic feathery and thin surface, as well as a hybrid form of exophytic condyloma and stromal invasion, and frequent coinfection of multiple different HPVs as a type of LSILs.

Adult↗
PubMed1998

Long-term effects of the intrauterine environment. The Northwestern University Diabetes in Pregnancy Center.

We sought to test the hypothesis that long-term postnatal development may be modified by metabolic experiences in utero. We enrolled offspring of women with pregestational diabetes (this included type 1 and type 2 diabetes) and gestational diabetes in a prospective study from 1977 to 1983. Fetal beta-cell function was assessed by measurement of amniotic fluid insulin (AFI) concentration at 32-38 weeks' gestation. Postnatally, offspring were seen yearly for neuropsychological testing, measurement of anthropometrics, and modified glucose tolerance testing. Neuropsychological control subjects were followed longitudinally. Additional control subjects had anthropometrics measured once, and a random subset of these had a single oral glucose challenge at 10-16 years. The rates of major neuropsychological disturbances in our cohort did not differ significantly from national estimates. However, aberrant maternal metabolism was associated with poorer intellectual performance and psychomotor development. The macrosomia observed at birth in offspring of diabetic mothers (ODM) resolves by 1 year of age. Obesity recurs in childhood; and by 14-17 years, the mean BMI is 24.6 +/- 5.8 kg/m2 in ODM versus 20.9 +/- 3.4 kg/m2 in control subjects. Obesity in adolescence is associated with sex, mother's weight, and AFI concentration. Impaired glucose tolerance (IGT) is found in 36% of ODM and is also associated with elevated amniotic fluid insulin in utero. In confirmation of our original hypothesis, aberrant maternal metabolism is associated with poorer intellectual and psychomotor development, obesity, and IGT in offspring. Excessive insulin secretion in utero, as assessed by AFI concentration, is a predictor of both obesity and IGT in adolescence. This study is a long-term prospective evaluation of the effects of maternal diabetes on pregnant women and their offspring. In this article, we report the results of the correlations between indexes of maternal and fetal metabolism during pregnancy and the offspring's subsequent physical, metabolic, and psychological development from birth through adolescence.

Adolescent↗
PubMed1997

Correlation between G1 cyclins and HPV in the uterine cervix.

G1 cyclin, as a candidate proto-oncogene, plays a key role as a cellular regulator through direct interaction with retinoblastoma gene product (pRB), p107, and cyclin-dependent kinase. Human papillomavirus (HPV) 16/18 E6/7 proteins may bind the unphosphorylated pRB and act as a down-regulator of cyclin D. However, this theory has not been proven and the relationship between cyclin E and HPV also remains unclear. Using formalin-fixed and paraffin-embedded cervical tissues, we examined for HPV types 16 and 18 by nested polymerase chain reaction (PCR), and for the accumulation of cyclin D1 and E by immunohistochemistry in 22 cases of normal cervix, 23 cases of cervical intraepithelial neoplasia (CIN), 39 cases of invasive squamous cell carcinoma (SCC), and 6 cases of adenocarcinoma. Cyclin index (CI) was defined as the percentage of positively labeled nuclei per 1000 cells. The accumulation of cyclin D1 was detected in the normal basal and parabasal epithelium and was markedly decreased in neoplastic epithelium (0.87% CI in CIN, 5.88% in SCC). However, cyclin E was absent in the normal cervix but increased in neoplastic epithelium (7.17% CI in CIN, 10.32% in SCC). Cyclin D1 expression was significantly low (p = 0.004), but cyclin E expression was significantly high (p = 0.026) in HPV-positive cases. Cyclin E plays a leading role in neoplastic transformation whereas cyclin D is down-regulated, especially when associated with HPV.

Adenocarcinoma↗
PubMed1997

Behavioral adjustment in children of diabetic mothers.

The aim of this study was to evaluate whether maternal diabetes in pregnancy may adversely affect the children's behavioral adjustment, in a sample of 201 mothers (68 with pre-gestational diabetes, 50 with gestational diabetes, and 83 with non-diabetic pregnancies) and their singleton offspring. After accounting for socioeconomic status, ethnicity and maternal attitudes, none of the Child Behavior Checklist ratings correlated significantly with maternal patient group or several indices of antepartum maternal metabolism. Child obesity, a common sequela of diabetic pregnancies, correlated positively with Internalizing Behavior problems and three narrow-band sub-scales: Somatic Complaints, Anxious/Depressed, and Social Problems. Results suggest that children of diabetic mothers are at increased risk for a variety of developmental disturbances. Screening for learning and behavioral difficulties should be made at regular pediatric visits, with follow-up evaluations warranted by positive indications, excessive weight gain, or other evolving medical concerns.

Adaptation, Psychological↗
PubMed1997

Increased macrosomia and perinatal morbidity independent of maternal obesity and advanced age in Korean women with GDM.

OBJECTIVE: To examine the impact of gestational diabetes mellitus(GDM) on perinatal outcome in a setting where influences of maternal age and obesity would be minimal. RESEARCH DESIGN AND METHODS: A case-control study was done to compare the outcome of pregnancy in 65 women with GDM and 153 women with normal carbohydrate metabolism matched for age, height, and prepregnancy weight. RESULTS: The frequencies of preeclampsia and primary cesarean sections were higher and delivery was earlier in pregnancies complicated by GDM. Birth weight, symmetry index, and chest circumference were greater, and macrosomia and need for phototherapy were more common in offspring of mothers with GDM. Cord-serum C-peptide and insulin concentrations were higher in the infants of mothers with GDM and were strongly correlated with birth weight and symmetry index. However, maternal age, prepregnancy weight, and prepregnancy BMI were not correlated with birth weight. Postprandial glucose levels during the first 2 weeks after diagnosis of GDM had associations with the infants' birth weight, symmetry index, and cord insulin concentration in the diet-treated patients with GDM. CONCLUSIONS: Antepartum maternal glucose metabolism was significantly associated with fetal hyperinsulinemia and excessive fetal growth in relatively nonobese Korean women. These findings support a direct role for metabolic factors in the adverse outcomes in pregnancies complicated by GDM.

Adult↗
PubMed1997

Sry gene detection in gonads of intersex patients using FISH.

A candidate gene for sex determination was localized within a 35 kb region of the Y chromosome immediately adjacent to the pseudoautosomal boundary. Here, we describe a study of Sry detection in the gonads of intersex patients including 5 male pseudohermaphrodite (MPH), 4 XX true hermaphrodite (TH) and each 1 mixed gonadal dysgenesis (MGD) and XX sex reversal, and in the clitoris of 3 female pseudohermaphrodite (FPH) by fluorescent in situ hybridization (FISH). Sry gene was observed in all cases of MPH and each case of MGD and sex reversal in contrast to bare expression in all cases of FPH and most of TH. To our knowledge, the Sry gene itself functions testicular determination in almost all intersex cases except true hermaphrodite, a distinguished type of intersex in a different pathogenesis. In addition, FISH might be useful to detect the translocated Sry gene and localize the signal with ease.

Adolescent↗
PubMed1997

Expression of alpha-1-antichymotrypsin in prostate carcinoma.

Prostate specific antigen (PSA) is a glycoprotein with the enzymatic activity of serine protease, the gene which is encoded in the human glandular kallikrein gene locus. Catalytically active PSA released into serum may be inactivated by a complex formation with alpha 1ACT (ACT) and alpha 2MG (MG), two major protease inhibitors. The serum complex-to-total PSA ratio can be used as a marker for the differentiation between prostate carcinoma (PCa) and a benign lesion because of a significant elevation of PSA binding to ACT in PCa. Apparently higher immunohistochemical expressions of PSA and ACT have been reported in PCa of low Gleason scores when compared with benign lesions. The fact that only normal secretory epitheliums are capable of producing ACT was recently proved by immunohistochemical and in situ hybridization methods. Our immunohistochemical study of ACT showed a tendency toward stronger expression in high Gleason grade PCa than in low Gleason grade Pca. Prostate intraepithelial neoplasia (PIN), as well as BPH, seldom react to ACT. Expression of ACT in normal ducts or acini was influenced by their location. In a normal prostate, expression of ACT was predominantly in secretory epithelial cells, with a minority of basal cells and rarely in the interdigitating neuroendocrine cells. Whereas the potency of ACT production in epithelial cells almost always appeared to be suppressed under normal conditions, it was noted that a strong expression of ACT was apparent in the normal ducts or acini near a high grade carcinoma with a weak reaction to ACT. ACT expression is much more enhanced in high grade carcinomas and in the residual normal acini adjacent to carcinomas of low ACT expression, presumably representing scale down the elevated PSA.

Carcinoma↗
PubMed1997

Nitrous oxide synthase expression in placenta of preeclampsia.

To compare the expression of endothelial nitrous oxide synthase (e-NOS), which plays a major role in vasoconstriction, in preeclampsia with that in the normotensive placenta and to identify whether or not e-NOS actually influences the pathogenesis of preeclampsia, we have studied the distribution and intensity of the endothelial isoform of NOS expression in preeclampsia (n = 121) and normal (n = 14) pregnancies. Archival paraffin-embedded tissues were immunostained with a polyclonal e-NOS antibody. E-NOS was stained predominantly in the endothelial cells of the umbilical cord and along the surface of the villi, especially within the cytoplasms of the syncytiotrophoblasts with a granular and punctuated pattern, but not in the trophoblastic island or in the intravillous capillaries. The degree of e-NOS expression in pregnancy-induced hypertension (PIH) was significantly lower than in normotensive placenta, and moreover in the patients lacking abruptio. The expression of e-NOS in preeclampsia has some correlation with patient age. In conclusion, the degree of e-NOS expression in cotyledon from PIH is far less than from control, it means a kind of hemodynamic alteration of the fetoplacental circulation in preeclampsia.

Adult↗
PubMed1997

Early malnutrition and child neurobehavioral development: insights from the study of children of diabetic mothers.

In this study we sought to discern whether disturbances in mothers' metabolism during pregnancy may exert long-range effects on the neurobehavioral development of the progeny. Participants were 139 women with diabetes in pregnancy and their singleton offspring. Serial estimates of circulating maternal fuels were obtained for each pregnancy, along with detailed records of perinatal course and outcome. Offspring were administered the Wechsler Intelligence Scale for Children--Revised (WISC-R) and Kaufman Test of Educational Achievement: Short Form (KTEA) at ages 7 to 11 years. The rate of WISC-R full-scale IQ scores below 70 in our cohort did not differ significantly from national estimates. Nonetheless, after statistically controlling for other influences, WISC-R verbal, performance, and full-scale IQ scores, and Bannatyne's indices of Verbal Conceptualization Ability, Acquired knowledge, Spatial Ability, and Sequencing Ability were inversely correlated with measures of maternal lipid and glucose metabolism in the second and third trimesters. KTEA Arithmetic scores were similarly correlated with measures of maternal lipids in the third trimester. All correlations indicate that poorer maternal metabolic regulation was attended by poorer child performance. The effects of maternal metabolism on fetal brain and neurobehavioral development are discussed as potential intermediary factors.

Child↗
PubMed1996

Ethnic variation in the incidence of stomach cancer in Illinois, 1986-1988.

Wide ethnic and geographic variation in stomach cancer incidence has been reported in Eastern and Western countries. Stomach cancer is reported to be the most common malignant neoplasm in Asia, specifically, China, Japan, and Korea. In contrast, stomach cancer incidence in the United States among Caucasians is low and among blacks, moderate to low. Only one other study has directly compared the rates of stomach cancer in the three ethnic groups (i.e., white, African American, and immigrant Korean) living in the same region. The authors extend their investigation by comparing the incidence rate of stomach cancer among the same three ethnic groups in the state of illinois from 1986 to 1988. In this study, the incidence of stomach cancer was observed to be lowest in whites, intermediate in African Americans, and highest in immigrant Koreans. The overall 3-year cumulative incidence rate from 1986 to 1988 was 62.6/100,000 (95% confidence interval (CI) 38.6-86.7), 28.2/100,000 (95% CI 25.7-31), and 22.5/100,000 (95% CI 21.5-23.5) for immigrant Koreans, African Americans, and whites, respectively. The 3-year age-adjusted cumulative incidence rate for immigrant Koreans (172/100,000) was approximately four-and eightfold higher than for African Americans (41/100,000) and whites (21/100,000). The incidence of stomach cancer increased as a function of age in both sexes. Although a higher rate was observed in males than in females, these rates were four-and eightfold higher in African Americans and immigrant Koreans, when compared with their white counterparts in both sexes. Despite a substantial reduction of stomach cancer incidence in the United States and other Western countries, it remains the most frequent malignancy in native and immigrant Koreans. The high rate of stomach cancer in immigrant Koreans compared with African Americans and white populations residing in Illinois indicates either a drastically disproportionate undercount of immigrant Koreans in the 1990 census or a profound genetic-environmental interaction.

Adolescent↗
PubMed1995

Prenatal and perinatal influences on long-term psychomotor development in offspring of diabetic mothers.

OBJECTIVE: Our purpose was to assess to what extent disturbances in antepartum maternal metabolism and perinatal complications and morbidities contribute to poorer psychomotor development in offspring of diabetic mothers. STUDY DESIGN: One hundred ninety-six pregnant women and their singleton offspring participated in this prospective cohort-analytic study. Ninety-five women had pregestational diabetes mellitus, and 101 women had gestational diabetes mellitus. Serial estimates of circulating maternal fuels were obtained throughout each index pregnancy along with detailed records of the perinatal course and outcome. Offspring were administered the psychomotor development index of the Bayley Scales of Infant Development at age 2 years and the Bruininks-Oseretsky Test Of Motor Proficiency at ages 6, 8, and 9 years. Tests were performed blinded to the mother's antepartum metabolic status, and perinatal history, and the child's previous test scores. Partial correlations and analyses of covariance were used to control for other influences and confounds, such as family socioeconomic status, racial or ethnic origin, patient group (i.e., pregestational or gestational diabetes mellitus), and sex of child. RESULTS: Children's average score on the Bruininks-Oseretsky test at ages 6 to 9 years correlated significantly with maternal second (p < 0.02) and third trimester (p < 0.001) beta-hydroxybutyrate. There was also a borderline association between the children's scores on the psychomotor development index at age 2 years and maternal third-trimester beta-hydroxybutyrate levels (p = 0.06). No other correlations approached significance. CONCLUSIONS: Intrauterine metabolic experiences continue to influence the neurodevelopmental course in offspring of diabetic mothers. Prevailing practices in diabetes management and obstetric and neonatal care appear to effectively mitigate the potential long-term effects of most perinatal complications and morbidities. Management and obstetric and neonatal care appear to effectively miltigate the potential long-term effects of most perinatal complications and morbidities.

Child↗
PubMed1995

Screening for gestational diabetes mellitus in Korea.

OBJECTIVES: To examine the effect of clinical characteristics on the prevalence of gestational diabetes mellitus (GDM) and to find the most effective screening program for GDM in Korea. METHODS: Universal screening with a 50-g glucose load at 24-28 weeks' gestation, as recommended by the Third International Workshop-Conference on Gestational Diabetes Mellitus, was carried out among 3581 consecutive Korean women. Women with a 1-h plasma glucose > or = 130 mg/dl underwent a 3-h 100-g oral glucose tolerance test. The women's clinical characteristics and risk factors for GDM were recorded at the time of the screening test. RESULTS: The overall prevalence of GDM in Korean women was 2.2 cases/100. Although only 1.3% of this population was obese, the prevalence of GDM was found to be significantly increased with increasing body mass index. When 135 mg/dl is used as a threshold, the number of women requiring a diagnostic test decreases to 19.5%, enabling identification of 98.8% of women with GDM. CONCLUSION: Universal screening using 135 mg/dl as a threshold and early screening of those with two or more risk factors represent the most effective paradigm for Korea.

Adult↗