Prognostic utility of ADAMTS13 activity for the atypical hemolytic uremic syndrome (aHUS) and comparison of complement serology between aHUS and thrombotic thrombocytopenic purpura

BACKGROUND: Atypical hemolytic uremic syndrome (aHUS) involves dysregulation of the complement system, but whether this also occurs in thrombotic thrombocytopenic purpura (TTP) remains unclear. Although these conditions are difficult to differentiate clinically, TTP can be distinguished by low (<10%) ADAMTS13 activity. The aim was to identify the differences in complement activation products between TTP and aHUS and investigate ADAMTS13 activity as a prognostic factor in aHUS. METHODS: We analyzed patients with thrombotic microangiopathy diagnosed as TTP (N=48) or aHUS (N=50), selected from a Korean registry (N=551). Complement activation products in the plasma samples collected from the patients prior to treatment and in 40 healthy controls were measured by ELISA. RESULTS: The levels of generalized (C3a), alternate (factor Bb), and terminal (C5a and C5b-9) markers were significantly higher (all P<0.01) in the patients than in the healthy controls. Only the factor Bb levels significantly differed (P=0.008) between the two disease groups. In aHUS patients, high normal ADAMTS13 activity (≥77%) was associated with improved treatment response (OR, 6.769; 95% CI, 1.605–28.542; P=0.005), remission (OR, 6.000; 95% CI, 1.693–21.262; P=0.004), exacerbation (OR, 0.242; 95% CI, 0.064–0.916; P=0.031), and disease-associated mortality rates (OR, 0.155; 95% CI, 0.029–0.813; P=0.017). CONCLUSION: These data suggest that complement biomarkers, except factor Bb, are similarly activated in TTP and aHUS patients, and ADAMTS13 activity can predict the treatment response and outcome in aHUS patients.

Association of MicroRNA Biogenesis Genes Polymorphisms with Ischemic Stroke Susceptibility and Post-Stroke Mortality / 대한뇌졸중학회지

BACKGROUND AND PURPOSE: MicroRNA (miRNA) expression has been examined in multiple conditions, including various cancers, neurological diseases, and cerebrovascular diseases, particularly stroke. Existing evidence indicates that miRNA biosynthesis and function play crucial roles in ischemic stroke physiology and pathology. In this study, we selected six known polymorphisms in miRNA-biogenesis genes; DICER rs13078A>T, rs3742330A>G; DROSHA rs10719T>C, rs6877842G>C; Ran GTPase (RAN) rs14035C>T; exportin 5 (XPO5) rs11077A>C. METHODS: We analyzed the associations between these polymorphisms and disease status and clinical factors in 585 ischemic stroke patients and 403 controls. Genotyping was performed with the polymerase chain reaction-restriction fragment length polymorphism method. RESULTS: The DICER rs3742330A>G (AA vs. AG+GG: adjusted odds ratio [AOR], 1.360; 95% confidence interval [CI], 1.024 to 1.807; P=0.034) and DROSHA rs10719T>C polymorphisms (TT vs. CC: AOR, 2.038; 95% CI, 1.113 to 3.730; P=0.021) were associated with ischemic stroke prevalence. During a mean follow-up of 4.80±2.11 years, 99 (5.91%) of the stroke patients died. In multivariate Cox proportional hazard regression models, a significant association was found between RAN rs14035 and survival of large artery disease patients with ischemic stroke (CC vs. TT: adjusted hazard ratio, 5.978; P=0.015). CONCLUSIONS: An association was identified between the DICER and DROSHA polymorphisms and ischemic stroke. Specifically, polymorphisms (rs3742330 and rs10719) were more common in stroke patients, suggesting that they may be associated with an increased risk of ischemic stroke.

MTHFR 3′-untranslated region polymorphisms contribute to recurrent pregnancy loss risk and alterations in peripheral natural killer cell proportions / 대한생식의학회지

OBJECTIVE: To identify the associations between polymorphisms of the 3′-untranslated region (UTR) of methylenetetrahydrofolate reductase (MTHFR) gene, which codes for an important regulatory enzyme primarily involved in folate metabolism, and idiopathic recurrent pregnancy loss (RPL) in Korean women. METHODS: The study population comprised 369 RPL patients and 228 controls. MTHFR 2572C>A, 4869C>G, 5488C>T, and 6685T>C 3′-UTR polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis or by TaqMan allelic discrimination assays. Natural killer cell proportions were determined by flow cytometry. RESULTS: The MTHFR 2572-5488-6685 (A-C-T) haplotype had an adjusted odds ratio of 0.420 (95% confidence interval, 0.178–0.994; p=0.048) for RPL. Analysis of variance revealed that MTHFR 4869C>G was associated with altered CD56⁺ natural killer cell percentages (CC, 17.91%±8.04%; CG, 12.67%±4.64%; p=0.024) and folate levels (CC, 12.01±7.18 mg/mL; CG, 22.15±26.25 mg/mL; p=0.006). CONCLUSION: Variants in the 3′-UTR of MTHFR are potential biomarkers for RPL. However, these results should be validated in additional studies of ethnically diverse groups of patients.

Clinical Characteristics of Colorectal Cancer Patients With a Second Primary Cancer

PURPOSE: The incidence of colorectal cancer is increasing due to a westernized dietary lifestyle, and improvements in treatment and diagnostic tools have resulted in more patients being confirmed of having multiple primary cancers. However, studies regarding multiple primary cancers are insufficient. In this study, the clinical aspects of patients with primary multiple cancers, including colorectal cancers, were investigated, and the results were compared to those of patients with primary colorectal cancer only. METHODS: Seven hundred eighteen patients who received surgery for colorectal cancer between March 2003 and September 2012 in CHA Medical Center were enrolled. A retrograde cohort was done for comparison of the two groups: those with and those without multiple primary cancer. The analysis was done according to sex, age, tumor location, tumor size, metastatic regional lymph-node number, vascular/lymphatic microinvasion, staging, tumor markers, microsatellite instability, and C/T subgroup of polymorphism in methylenetetrahydrofolate reductase. RESULTS: Of the 718 subjects, 33 (4.6%) had multiple primary cancers: 12 (36.4%) synchronous and 21 (63.6%) metachronous. The malignancy most frequently accompanying colorectal cancer was gastric cancer, followed by thyroid, prostate, and esophageal malignancies in that order. In the comparison between groups, mean age, tumor location, and microsatellite instability showed statistically significant differences; others parameters did not. CONCLUSION: The incidence of multiple primary cancers, including colorectal cancer, is increasing. Therefore, defining the characteristics of patients with multiple primary cancers is crucial, and those characteristics need to be acknowledged in the follow-up of colorectal cancer patients.

Analysis of an Association between Single Nucleotide Polymorphisms of Vascular Endothelial Growth Factor Gene and Risk of Cerebral White Matter Lesion

BACKGROUND: Endothelial dysfunction is suggested to be one of the pathogenesis of cerebral white matter lesion (cWML). Vascular endothelial growth factor (VEGF) plays a crucial role in angiogenesis and integrity of vascular endothelial cell, and altered expression of VEGF gene induces vascular diseases including cerebrovascular diseases. The objective of this study is to investigate whether single nucleotide polymorphism (SNP) of VEGF gene confers an increased risk of cWML. METHODS: Total 337 study subjects without history of stroke were included. The presence and severity of cWML were measured on fluid-attenuated inversion recovery image. Genotypes of VEGF -2578G>A, -1154G>A, -634G>C and +936C>T were analyzed. RESULTS: Among 337 study subjects, cWML was found in 208 patients (62%), and fifty-eight cases (17%) of them had overt cWML. In univariate analysis, age, female sex and plasma total homocysteine level (tHcyt) were higher in the mild and overt cWML group than no cWML group (p<0.05). The percentage of previous history of hypertension and the value of systolic blood pressure were higher in overt cWML group than no cWML group. In univariate and logistic regression analysis, none of four tested VEGF SNPs was significantly different between control group, mild and overt cWML groups. There was no difference between plasma tHcyt levels and each VEGF SNPs in control group and cWML groups. CONCLUSIONS: In this study, old age, female sex, hypertension and plasma tHcyt were associated with cWML. However, we failed to find an association between cWML and VEGF gene polymorphism, which may indicate that genetic polymorphism of VEGF does not play a direct role in the pathogenesis of cWML.

Relationship between Metabolic Syndrome and MTHFR Polymorphism in Colorectal Cancer

PURPOSE: There have been studies on the relations between metabolic syndrome and colorectal cancer or on the relations between methylenetetrahydrofolate reductase (MTHFR) polymorphism and colorectal cancer, but reports on the relationship between metabolic syndrome, MTHFR polymorphism and colorectal cancer all together are rare. The aim of this study is to find the interrelation between metabolic syndrome and MTHFR polymorphism in colorectal cancer. METHODS: This study investigated 255 colorectal cancer patients (cancer group) who underwent surgery in our hospital from March 2003 to December 2008 and compared those patients to 488 healthy patients (control group). The diagnostic criterion for metabolic syndrome was based on the National Cholesterol Education Program-Adult Treatment Panel III (NCEP ATP III), and the MTHFR 677 polymorphism was analyzed. RESULTS: When colorectal cancer patients and patients in the control group were classified as MTHFR 677 subtypes, there was no difference between the two groups: CC 87 (34.1%), CT 134 (52.6%), and TT 34 (13.3%) for the cancer group and CC 145 (32.4%), CT 238 (53.1%), and TT 65 (14.5%) for the control group. Distributions of MTHFR 677C/T genotype and allele frequencies in the individuals with and without metabolic syndrome in the cancer group showed no differences. Moreover, we could find no differences in distributions of MTHFR 677C/T genotypes in the clinical and the biomedical variables of individuals with and without metabolic syndrome in the cancer group. CONCLUSION: Our results show no relation between metabolic syndrome and MTHFR polymorphism in colorectal cancer. However, a further prospective study, based on a precise diagnostic criterion for metabolic syndrome, is needed.

Association between Single Nucleotide Polymorphisms of alpha2A-, alpha2B-, and alpha2C-Adrenergic Receptor Genes and Risk of Cerebral White Matter Lesion / 대한뇌졸중학회지

BACKGROUND: An alpha2-adrenergic receptor (alpha2-AR, ADRA2) mediates induction of hypotension and inhibition of lipolysis and insulin secretion. We evaluated whether single nucleotide polymorphisms (SNPs) of alpha2A (ADRA2A), alpha2B (ADRA2B), and alpha2C (ADRA2C) adrenergic receptors are associated with cerebral white matter lesion (cWML). METHODS: Total 336 study subjects who had no stroke were enrolled in this study. The Indices of cWML include total WML (TWML), periventricular WML (PVWML), and subcortical WML (SCWML) on brain fluid-attenuated inversion recovery (FLAIR) image. Common genetic variants of ADRA2A (1780G>A), ADRA2B (Ins/Del301-303), and ADRA2C (Ins/Del322-325) were examined. RESULTS: Among 336 study subjects, cWML was found in 66 patients (20%). In multivariate analysis, there were no significant effects of all tested ADRA2 polymorphisms on TWML. Significant association of ADRA2A 1780 AA genotype was found in PVWML (OR: 3.368, 95% CIs: 1.280-8.865, adjusted p-value after false discovery rate (FDR) correction=0.014) but not SCWML. CONCLUSION: Although SNPs of three ADRA2 subtypes failed to reach a significance in overall risk for cWML, the ADRA2A 1780G>A polymorphism may be associated with development of PVWML.

ADAMTS13 Gene Mutations in Children with Hemolytic Uremic Syndrome

We investigated ADAMTS13 activity as well as the ADAMTS13 gene mutation in children with hemolytic uremic syndrome (HUS). Eighteen patients, including 6 diarrhea-negative (D-HUS) and 12 diarrhea-associated HUS (D+HUS) patients, were evaluated. The extent of von Willebrand factor (VWF) degradation was assayed by multimer analysis, and all exons of the ADAMTS13 gene were PCR-amplified using Taq DNA polymerase. The median and range for plasma activity of ADAMTS13 in 6 D-HUS and 12 D+HUS patients were 71.8% (22.8-94.1%) and 84.9% (37.9-119.9%), respectively, which were not statistically significantly different from the control group (86.4%, 34.2-112.3%) (p>0.05). Five ADAMTS13 gene mutations, including 2 novel mutations [1584+2T>A, 3941C>T (S1314L)] and 3 polymorphisms (Q448E, P475S, S903L), were found in 2 D-HUS and one D+HUS patients, which were not associated with deficiency of ADAMTS13 activity. Whether these mutations without reduced ADAMTS13 activity are innocent bystanders or predisposing factors in HUS remains unanswered.

Association of Methylenetetrahydrofolate Reductase (MTHFR 677C>T and 1298A>C) Polymorphisms and Haplotypes with Silent Brain Infarction and Homocysteine Levels in a Korean Population

PURPOSE: Methylenetetrahydrofolate reductase (MTHFR) is the main regulatory enzyme for homocysteine metabolism. In the present study, we evaluated whether the MTHFR 677C>T and 1298A>C gene polymorphisms are associated with SBI and plasma homocysteine concentration in a Korean population. MATERIALS AND METHODS: We enrolled 264 patients with SBI and 234 healthy controls in South Korea. Fasting plasma total homocysteine (tHcy) concentrations were measured, and genotype analysis of the MTHFR gene was carried out. RESULTS: The plasma tHcy levels were significantly higher in patients with SBI than in healthy controls. Despite a significant association between the MTHFR 677TT genotype and hyperhomocysteinemia, the MTHFR 677C>T genotypes did not appear to influence susceptibility to SBI. However, odds ratios of the 1298AC and 1298AC + CC genotypes for the 1298AA genotype were significantly different between SBI patients and normal controls. The frequencies of 677C-1298A and 677C-1298C haplotypes were significantly higher in the SBI group than in the control group. CONCLUSION: This study demonstrates that the MTHFR 1298A>C polymorphism is a risk factor for SBI in a Korean population. The genotypes of 677C>T and 1298A>C polymorphisms interact additively, and increase the risk of SBI in Korean subjects.

Gender-specific Association between Polymorphism of Vascular Endothelial Growth Factor (VEGF 936C>T) Gene and Patients with Stomach Cancer

PURPOSE: Angiogenesis plays an important role in the growth, progression, and metastasis of tumors. Vascular endothelial growth factor (VEGF) overexpression has been associated with advanced stage and poor survival in several cancers. We investigated the present case-control study to determine whether there is an association between the VEGF 936C>T polymorphism and stomach cancer. PATIENTS AND METHODS: The association of functional single nucleotide polymorphisms (SNPs) of the VEGF gene with stomach cancer development was evaluated in a case-control study of 154 Korean stomach cancer patients. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. RESULTS: Our results revealed significant association of T allele-bearing genotypes with increased risk for stomach cancer development. Genotype frequencies of the VEGF 936C>T polymorphisms were significantly different between patient and control groups (CT, AOR: 2.007, 95% CI: 1.277-3.156, TT, AOR: 4.790, 95% CI: 1.174-19.539, CT+TT, AOR: 2.147, 95% CI: 1.382-3.337). When stratified by gender and age, genotype frequencies were significantly different for stomach cancer in women and in patients younger than 55 years (in women, CT, OR: 3.049, 95% CI: 1.568-5.930, CT+TT, OR: 3.132, 95% CI: 1.638-5.990; in T polymorphism is a susceptibility factor for stomach cancer, at least in Korean. These observations, however, require further confirmation by a larger multi-ethnic study.

Frequency of Pro475Ser Polymorphism of ADAMTS13 Gene and Its Association with ADAMTS-13 Activity in the Korean Population

PURPOSE: The in vitro study suggested that proline to serine polymorphism in codon 475 (C1423T) of the A Disintegrin and Metalloprotease with ThromboSpondin type 1 repeats-13 (ADAMTS-13) gene is related to reduced activity of ADAMTS- 13. In this study, the frequency of the Pro475Ser polymorphism in Koreans was studied and plasma ADAMTS-13 activity was measured to find out whether this polymorphism contributes to decreased ADAMTS-13 activity in Koreans. PATIENTS AND METHODS: The frequency of the C1423T allele of the ADAMTS13 gene was studied along with measuring plasma ADAMTS-13 activity in 250 healthy Korean individuals. RESULTS: The allele frequency of C1423T polymorphism was 4%, and the median activity of CT type was 107 (69-143)%, which was lower than in controls with the CC genotype [118 (48-197)%, (p=0.021)]. CONCLUSION: Therefore, the Pro475Ser polymorphism seems to be popular in the Korean population, and attenuates ADAMTS-13 plasma activity.

Influence of Combined Methionine Synthase (MTR 2756A > G) and Methylenetetrahydrofolate Reductase (MTHFR 677C > T) Polymorphisms to Plasma Homocysteine Levels in Korean Patients with Ischemic Stroke

PURPOSE: Methionine synthase (MTR) and 5,10-methylenetetrahydrofolate reductase (MTHFR) are the main regulatory enzymes for homocysteine metabolism. The present case- control study was conducted to determine whether there is an association between the MTR 2756A > G or MTHFR 677C > T polymorphism and plasma homocysteine concentration in Korean subjects with ischemic stroke. MATERIALS AND METHODS: DNA samples of 237 patients who had an ischemic stroke and 223 age and sex-matched controls were studied. MTR 2756A > G and MTHFR 677C > T genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: Frequencies of mutant alleles for MTR and MTHFR polymorphisms were not significantly different between the controls and cases. The patient group, however, had significantly higher homocysteine concentrations of the MTR 2756AA and MTHFR 677TT genotypes than the control group (p=0.04 for MTR, p=0.01 for MTHFR). The combined MTR 2756AA and MTHFR 677TT genotype (p= 0.04) and the homocysteine concentrations of the patient group were also higher than those of the controls. In addition, the genotype distribution was significant in the MTHFR 677TT genotype (p=0.008) and combined MTR 2756AA and MTHFR 677TT genotype (p=0.03), which divided the groups into the top 20% and bottom 20% based on their homocysteine levels. CONCLUSION: The results of the present study demonstrate that the MTR 2756A > G and MTHFR 677C > T polymorphisms interact with elevated total homocysteine (tHcy) levels, leading to an increased risk of ischemic stroke.

A pilot study of neuroprotection with umbilical cord blood cell transplantation for preterm very low birth weight infants / 소아과

PURPOSE: Preterm very low birth weight infant have high rate of adverse neurodevelopmental sequale. Recently, there have been lots of reports that human umbilical cord blood transplantation ameliorates functional deficits in animal models as hypoxic ischemic injury. This pilot study was undertaken to determine the clinical efficacy and safety of autologous umbilical cord blood cell transplantation for preventing neurodevelopmental sequale in perterm VLBW. METHODS: Subjects were 26 preterm infants whose birth weight are less than 1,500 g and delivered under the intrauterine period 34 weeks. Autologous umbilical mononuclear cells (about 5.87x10(7)/kg) were injected to neonate via the umbilical vein on the postnatal 24-48 hour. The therapeutic efficacy was assessed by numbers of nucleated RBC, urinary uric acid/creatinine ratio, concentration of neuron specific enolase (NSE), interleukin 6 (IL6), interleukin-1beta (IL-1beta), and glial cell derived neurotrophic factor (GDNF) in serum and cerebrospinal fluid on day 1 and 7. RESULTS: There were no significant differences in the numbers of the nucleated RBC, urinary uric acid/creatinine ratio, concentration of creatine kinase between the transplanted infants and controls. But the nucleated RBC is more likely to be rapidly discharged in the transplanted group. In the transplanted group, the concentrations of IL6, IL-1beta, and GDNF were no significant difference between day 1 and 7, although GDNF seemed to be elevated. Serum NSE concentration was significantly elevated after transplantation, but not in CSF. CONCLUSION: It is suggested that autologous umbilical cord blood transplantation in preterm very low birth weight infant is safe to apply clinical practice. Long term follow up study should be needed to evaluate the potential therapeutic effect of umbilical cord blood transplantation for neuroprotection.

The Effect of Folic Acid to the Level of Homocysteine and Analysis of the Factors in Epilepsy Patients / 대한간질학회지

BACKGROUND: Folic acid has been frequently used for hyperhomocyesteinemia in various diseases and decreases the level of homocysteine. OBJECTIVES: To assess the effect of folic acid in the level of homocysteine in epilepsy patients, and to analyze factors affecting its responsiveness and the difference of its efficacy according to methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism. METHODS: Total 75 epilepsy patients with antiepileptic drugs (AEDs) therapy were included. 41 patients had normal level of homocysteine and 34 patients with hyperhomocysteinemia (> or =12 micro mol/ ) were supplemented with folic acid for 1 year. Thirty-four patients with hyperhomocyteinemia were divided into two groups according to the responsiveness of homocysteine to folic acid; decrease group (DG) and non-decrease group (NDG). RESULTS: The level of homocysteine in patients with hyperhomocysteinemia was significantly decreased after administration of folic acid, comparing with patients with normal level. DG was younger and had more male gender, shorter duration of seizure, and initial higher homocysteine level, compared to NDG (p<0.05). Patients with mutant type of MTHFR (CT+TT) had more decreased homocysteine level after supplement of folic acid, but had more increased homocysteine level without supplement of folic acid. Comparing between MTHFR genotypes, TT type had the most decreased homocysteine level than others, but there was no significance. CONCLUSION: Folic acid is useful treatment of hyperhomocysteinemia in epilepsy patients and the supplement of folic acid might be considered in patients with mutant type of MTHFR regardless of homocysteine level. The effect of folic acid supplement is greater in younger age, male sex, shorter duration of seizure, and initial higher homocysteine level.

Genetic Polymorphism of Thymidylate Synthase Enhancer Region (TSER) in Patients with Silent Brain Infarction

BACKGROUND: Hyperhomocysteinemia is an independent risk factor for silent brain infarction (SBI). The plasma homocysteine (pHcy) level is influenced by the activities of enzymes such as 5,10-methylenetetrahydrofolate reductase (MTHFR). Thymidylate synthase (TS) also competes with MTHFR for their common cofactor, 5,10-methylenetetrahydrofolate (5,10-meTHF). The polymorphism of thymidylate synthase enhancer region (TSER) might affect homocystein metabolism by modulating the activity of TS, and may be a determinant of SBI by elevating pHcy concentrations. Therefore, we studied the polymorphism of TSER in patients with SBI. METHODS: 98 patients with SBI and 92 healthy controls were included in the study. The genotypes of TSER and MTHFR were identified with the PCR-RFLP methods. RESULTS: The mean pHcy level was significantly higher in SBI patients (13.5+/-8.5 micro mol/L) than in controls (10.3+/-4.1 micro mol/L)(p<0.01). The frequencies of MTHFR C677T genotype and TSER 28 bp tandem repeat genotype were not different between the patients and the controls. The pHcy concentrations were not considerably different between the 3R3R and 2R3R genotypes in the population as a whole (p=0.712), nor in subsets of patients with SBI (p=0.484). However, in cases with the TSER 3R3R genotype, the pHcy level was significantly higher in patients (14.0+/-10.26 micro mol/L) than in controls (9.9+/-3.1 micro mol/L)(p=0.006). Folate and pHcy was inversely correlated in the SBI patients with the TSER 3R3R genotype (r=-0.424, p=0.039). CONCLUSIONS: Our findings suggest that the TSER genotype is not a major determinant of pHcy concentrations and is neither a risk factor for SBI in the Korean population. However, further study will be needed to confirm this findings.

Distributions of MTHFR Gene Polymorphism according to the Location of Colon Cancer

PURPOSE: Colon carcinogenesis seems to vary according to the original location of tumor, especially theright and the left sides. Two common methylenetetrahydrofolate reductase (MTHFR) polymorphisms, 677C->T and 1298A->C, are now known. Especially, the TT type of the 677C->T mutation shows reduced catalytic activity at a rate 30% that of wild type. The aim of this study is to investigate the distributions of MTHFR polymorphisms of 677C->T and 1298A->C according to the location of the colon cancer. METHODS: Blood samples were collected from 112 patients diagnosed in our hospital, as having colon cancer: 34 proximal and 78 distal cases to the splenic flexure and 448 healthy control subjects. In order to characterize MTHFR polymorphisms, we applied the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: The distributions of MTHFR 677C->T polymorphisms as genotypes CC, CT, and TT were 32.4%, 53.1%, and 14.5% in the control group, and 34.8%, 58.0%, and 7.1% in the cancer group (P=0.056). In the 34 proximal cancers, the CC, CT, and TT distributions were 44.1%, 55.9%, and 0% (PC polymorphism by genotypes, AA, AC, CC were 69.6%, 28.6%, and 1.8% in the control group, and 58.9%, 38.4%, and 2.7% in the cancer group. The proximal and the distal groups show genotype distributions of 44.1%, 53.0%, and 2.9% and 65.4%, 32.0%, and 2.6%, respectively, but the differences were not statistically significant. CONCLUSIONS: There are no definite differences between control subjects and colon-cancer patients in the two polymorphisms 677C->T and 1298A->C. However, the TT genotype shows a lower frequency in the cancer group than in the control group with a marginal statistical value (P=0.056), which suggest a reduced risk of cancer incidence for this type, compared with a CC or a CT type.

ADAMTS13 Activity in Childhood Hemolytic Uremic Syndrome(HUS)

PURPOSE: HUS usually occurs in children after infection with shiga toxin-producing microorganism(D+HUS). In contrast, non-postdiarrheal(D-) HUS occurs at any age and has a high rate of relapse and a poor prognosis. The clinical presentation of D-HUS is similar to that of thrombotic thrombocytopenic purpura(TTP). Recently severe deficiencies of ADAMTS13 were reported not only in TTP and D- HUS but also in D+ HUS during their acute phase. The purpose of the study is to evaluate the plasma ADAMTS13 activity in D+ and D-HUS. METHODS: Nineteen children with HUS(D+ HUS 12 and D- HUS 7) were enrolled. The assays of plasma ADAMTS13 activity were performed during the acute stage in the D+ HUS and at various stages of relapsing courses in the D- HUS patients by multimer assay, based on electrophoresis. RESULTS: The median plasma activity of ADAMTS13 in D+ HUS and D- HUS were 80.9%(37.8-132.4%) and 53.9%(1.0-94.1%), respectively, which were not statistically significantly different from control(86.4%, 34.2-112.3%)(P>0.05). One boy with D- HUS had severe deficiency of ADAMTS13(1.0%). His platelet count was normalized temporarily by fresh frozen plasma infusion. CONCLUSION: We have demonstrated that there is no significant difference of the plasma ADAMTS13 activity between D+ HUS, D- HUS and control. We detected severe deficiency of ADAMTS13 in one boy who presented with relapsing episodes of D- HUS. ADAMTS13 deficiency should be considered in the subgroup of D- HUS especially with early onset and recurrent courses. Plasma therapy can be beneficial in this subgroup.

The Relationship of Methylenetetrahydrofolate Reductase(MTHFR) C677T, Thymidylate Synthase(TS) Gene Polymorphism and Epilepsy / 대한간질학회지

PURPOSE: Thymidylate synthase (TS) gene encodes a tightly regulated enzyme that catalyzes the conversion of deoxyuridylate to thymidylate, and contains a tandem repeat polymorphism, of which a triple repeat is associated with increased expression of TS. TS is a key enzyme in the folate metabolism and compete with methylenetetrahydrofolate reductase (MTHFR) for limiting supplies of folate required for the remethylation of homocysteine. We studied to clarify the association between MTHFR C677T and TS polymorphism and prognosis in epilepsy. METHODS: 119 patients with antiepileptic drug more than one year were included. We investigated the MTHFR C677T and TS polymorphism using PCR, and analyzed the association between plasma homocysteine, folate levels, clinical profiles (especially seizure frequencies) and polymorphism. RESULTS: In seizure frequencies during one year, TT type in MTHFR and 3R3R type in TS polymorphism had higher frequencies than any other types without statistical significance. In plasma homocysteine levels, TT type had significantly higher homocsyteine levels than any other types, but 3R3R type had higher homocsyteine levels than any other types without statistical significance. Combined analysis of MTHFR C677T and TS polymorphism revealed that plasma homocysteine levels (18.22+/-8.32 micromol/l; p=0.039) and seizure frequencies (6.38+/-7.35/year; p=0.04) in patients with TT/3R3R were significantly higher than any other groups. A significant correlation between plasma homocysteine levels and seizure frequencies also was shown in multivariate linear regression analysis (B=0.160, Std error=0.069, adjusted R2=0.039, p=0.021). CONCLUSION: Epileptic patients with hyperhomocysteinemia, especially when combined with mutant allele for MTHFR and TS genes, have higher seizure frequencies. Therefore, our results suggest that the genotyping for the MTHFR and TS polymorphism may become a useful indicator in determining prognosis of epilepsy.

The Associtation between Methylenetetrahydrofolate Reductase Gene Polymorphisms and a Risk of Spontaneously Aborted Embryos / 대한불임학회지

OBJECTIVE: This study was performed to understand the influence of the methylenetetrahydrofolate reductase (MTHFR C677T and A1298C) genotypes on the spontaneously aborted embryos. METHODS: DNA was extracted from tissue samples of 95 spontaneously aborted embryos and 100 samples of normal children randomly and 449 samples of normal adults were selected as the controls. MTHFR genotypes were determined by a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. RESULTS: The aborted embryo group had higher frequency of MTHFR 677CC type (p=0.014) and lower 677CT type (p=0.063) than the controlled child group. The frequency of MTHFR 677CT type was drastically lower than that of controlled adult group (p=0.032). In the MTHFR C677T/A1298C combination, 677CC/1298AC genotype of the aborted embryo was significantly higher (p=0.034) than that of controlled child group, but it was not statistically significant in controlled adult group (p=0.063). CONCLUSION: MTHFR 677CC and MTHFR 677CC/1298AC genotypes may represent genetic markers for the risk of spontaneously aborted embryos at least in Koreans.

Polymorphism in the DNA Repair Gene XRCC1 Associated with Squamous Cell Carcinoma and Basal Cell Carcinoma of the Skin in Koreans

PURPOSE: DNA in most cell is regularly damaged by endogenous and exogenous mutagens. Unrepaired damage resulted in apoptosis or may lead to unregulated cell growth and cancer. Inheritance of genetic variants at one or more loci results in an reduced DNA repair capacity. These polymorphisms are highly prevalent in the population, and therefore the attributable risks for cancer could be high. Several studies have documented that polymorphisms of XRCC1, XPD and XRCC3 are associated with skin cancer, especially, XRCC1 among of them has been reported frequently. So, this study involves the relationship between mutation of XRCC1 of squamous cell and basal cell cancer of the skin and risk of cancer development in Korean population. METHODS: In case control study, study population (n=100, each cancer) is patients who were pathologically diagnosed as skin cancer(squamous cell carcinoma and basal cell carcinoma) in Yonsei Wonju Christian Hospital and Bundang CHA General Hospital between 1998 and 2004. The samples of DNA from whom no history of premalignant skin lesion and other malignant diseases were reported belonged to the control group(n=210). Blood and tissue samples were analyzed for presence of XRCC1 Arg399Glu, Arg280His, Arg194Trp using PCR/ RFLP method. RESULTS: For Korean, there was a significant correlation between XRCC1 Arg399Gln gene mutation and risk of basal cell carcinoma development(Arg 399Gln(GA), p=0.012, OR=2.016, 95% CI; 1.230-3.305) /Arg399Gln (AA), p=0.011, OR=1.864, 95% CI; 1.149-3.026)). And, there was also significant correlation between XRCC1 Arg194Trp and risk of skin squamous cell carcinoma development (Arg194Trp (CT+TT), p=0.041, OR=0.537, 95% CI; 0.301-0.960)). In contrast, there was no significant correlation between XRCC1 Arg280His and risk of either basal cell carcinoma or squamous cell carcinoma development. CONCLUSION: Our result present that XRCC1 Arg399 Gln in basal cell carcinoma and XRCC1 Arg194Trp in squamous cell carcinoma have possibility of cancer risk and biomarker in Korean population. But XRCC1 Arg280 His known having cancer risk on other studies is not associated with cancer risk to squamous cell carcinoma and basal cell carcinoma in Korean population.