Avoiding unnecessary intraoperative sentinel lymph node frozen section biopsy of patients with early breast cancer.

Purpose: After the publication of the ACOSOG (American College of Surgeons Oncology Group) Z0011 trial, the rate of axillary lymph node dissection has reduced. Thus, the need for intraoperative frozen section biopsy of sentinel lymph nodes (SLNs) has become controversial. We identified patients for whom intraoperative SLN frozen section biopsy could be omitted and found that frozen section biopsy rate can be reduced. Methods: We reviewed the records of patients with tumors ≤5 cm in diameter who underwent breast-conserving surgery between January 2013 and December 2019 at Seoul St. Mary's Hospital. Clinicopathological and imaging characteristics were compared according to number of positive SLNs (0-2 SLNs positive vs. ≥3 SLNs positive). Results: A total of 1,983 patients were included in this study. Thirty-two patients (1.6%) had at least 3 positive SLNs. Patients with ≥3 positive SLNs had significantly larger tumors and were more frequently high-grade tumors (P < 0.001 and P = 0.002, respectively). Identification of suspicious lymph nodes on imaging studies was also associated with the presence of ≥3 positive SLNs (hazard ratio, 11.54; 95% confidence interval, 4.42-30.10). All patients with none or only 1 suspicious lymph node on any imaging modality (n = 647, 32.6%) had 0-2 positive SLNs. Also, among patients with clinical T1-stage tumors and at least 2 suspicious lymph nodes on only 1 imaging modality (n = 514, 25.9%), only 2 cases had ≥3 positive SLNs. Conclusion: We found that intraoperative SLN frozen biopsy could be omitted in patients using tumor size and axillary lymph node status on imaging modality.

Treatment of 10-mm-Deep or Greater Uncontained Tibial Bone Defects in Primary Total Knee Reconstruction without Metal Augmentation: Autologous Oblique Structural Peg Bone and Cancellous Chip Bone Grafting.

BACKGROUD: In this study, we report satisfactory clinical and radiological outcomes after autologous oblique structural peg bone and cancellous chip bone grafting without metal augmentation, including the use of a metal wedge, block, or additional stem, for patients with ≥ 10-mm-deep uncontained medial proximal tibial bone defects in primary total knee replacement. METHODS: The study group included 40 patients with primary total knee replacement with ≥ 10-mm-deep uncontained tibial bone defects who underwent autologous oblique structural peg bone and cancellous chip bone grafting and were followed-up for at least 1 year. Tibial cutting was performed up to a depth of 10 mm from the articular surface of the lateral tibial condyle, after which the height and area of the remaining bone defect in the medial condyle were measured. The bone defect was treated by making a peg bone and chip bone using excised segments of the tibia and femur. In all cases, the standard tibial stem and full cemented fixation techniques were used without metal augmentation. Preoperative and final follow-up radiologic changes and clinical measures were compared, and prosthesis loosening and bone union were checked radiologically at final follow-up. RESULTS: The mean depth of the bone defects was 10.9 mm, and the mean percentage of the area occupied by bone defects in the axial plane was 18.4%. The mean mechanical femorotibial angle was corrected from 19.5° varus preoperatively to 0.2° varus postoperatively (p < 0.002). There was no prosthesis loosening, and all cases showed bone union at the 1-year postoperative follow-up. CONCLUSIONS: Even in patients with uncontained tibial bone defects ≥ 10-mm deep in primary total knee replacement, if the defect occupies less than 30% of the cut surface, autologous oblique structural peg bone and cancellous chip bone grafting can be used to achieve satisfactory outcomes with a standard tibial stem and no metal augmentation.

Influence of Atlantoaxial Fusion on Sagittal Alignment of the Occipitocervical and Subaxial spines in Os Odontoideum with Atlantoaxial Instability.

Study Design: Retrospective case analysis. Purpose: We hypothesized that larger the C1-C2 fusion angle, greater the severity of the sagittal malalignment of C0-C1 and C2- C7. Overview of Literature: In our experience, instances of sagittal malalignment occur at C0-C1 and C2-C7 following atlantoaxial fusion in patients with Os odontoideum (OO). Methods: We assessed 21 patients who achieved solid atlantoaxial fusion for reducible atlantoaxial instability secondary to OO. The mean patient age at the time of the operation was 42.8 years, and the mean follow-up duration was 4.9 years. Radiographic parameters were preoperatively measured and at the final follow-up. The patients were divided into two groups (A and B) depending on the C1-C2 fusion angle. In group A (n=11), the C1-C2 fusion angle was ≥22°, whereas in group B, it was <22°. The differences in the radiographic parameters of the two groups were evaluated. Results: At the final follow-up, the C1-C2 angle was increased. However, this increase was not statistically significant (18° vs. 22°, p=0.924). The C0-C1 angle (10° vs. 5°, p<0.05) and C2-C7 angle (22° vs. 13°, p<0.05) significantly decreased. The final C1-C2 angle was negatively correlated with the final C0-C1 and C2-C7 angles. The final C0-C1 angle (4° vs. 6°, p<0.05) and C2-C7 angle (8° vs. 20°, p<0.05) were smaller in group A than in group B. After atlantoaxial fusion, the C0-C1 range of motion (ROM; 17° vs. 9°, p<0.05) and the C2-C7 ROM (39° vs. 31°, p<0.05) were significantly decreased. Conclusions: We found a negative association between the sagittal alignment of C0-C1 and C2-C7 after atlantoaxial fusion and the C1-C2 fusion angle along with decreased ROM. Therefore, overcorrection of C1-C2 kyphosis should be avoided to maintain good physiologic cervical sagittal alignment.

Posterior Sublaminar Wiring and/or Transarticular Screw Fixation for Reducible Atlantoaxial Instability Secondary to Symptomatic Os Odontoideum: A Neglected Technique?

STUDY DESIGN: Retrospective case analysis. PURPOSE: We retrospectively evaluated the clinical and radiological outcomes of posterior sublaminar wiring (PSLW) and/or transarticular screw fixation (TASF) for reducible atlantoaxial instability (AAI) secondary to os odontoideum. OVERVIEW OF LITERATURE: Limited information is available about the surgical outcomes of symptomatic os odontoideum with AAI. METHODS: We examined 23 patients (12 women and 11 men) with os odontoideum and reducible AAI. The average age of the patients at the time of the operation was 44.2 years. The average follow-up duration was 4.5 years. Thirteen patients with anterior AAI underwent PSLW alone, while 10 patients with combined (anterior+posterior) AAI underwent PSLW and TASF. An autogenous iliac bone graft was used for all patients. Nine patients complained of neck or suboccipital pain, and 14 complained of myelopathy. RESULTS: Angulational instability (preoperative 18.7°±8.9° vs. postoperative 2.1°±4.6°, p<0.001), translational instability (16.3±4.9 mm vs. 1.8±2.2 mm, p<0.001), and segmental angle of the C1-C2 joint (23.7°±7.2° vs. 28.4°±3.8°, p<0.05) showed significant improvement postoperatively. Neck Visual Analog Scale score (6.2±2.4 vs. 2.5±1.8, p<0.05) and the modified Japanese Orthopedic Association (9.1±3.1 vs. 13.2±2.6, p<0.05) score also improved, with a recovery rate of 51.8%. Among the three patients who developed nonunion and/or wire breakage, one underwent revision surgery with repeat PSLW and was finally able to achieve fusion. The final fusion rate was 91.3%. CONCLUSIONS: PSLW and/or TASF provided satisfactory clinical and radiological outcomes in reducible AAI secondary to os odontoideum without significant neurological complications. Our results suggest that PSLW and/or TASF can be considered a viable surgical option over segmental fixation in highly selected cases of os odontoideum with reducible AAI.

Psychological Vulnerability of Residents of Communities Affected by the Hebei Spirit Oil Spill.

OBJECTIVE: Psychological health is an important issue after disasters. This study aimed to investigate the prevalence of psychological symptoms among 993 residents of Taean District in South Korea after the Hebei Spirit oil spill and to examine determinants of vulnerability in residents' psychological symptoms. METHODS: Symptoms of post-traumatic stress (PTS), depression, suicidal ideation, and anxiety were assessed by questionnaires, and the responses were analyzed by using the survey analysis considering the sampling frame. RESULTS: Among the study subjects, the symptom prevalences of PTS, depression, suicidal ideation, and anxiety were 19.5%, 22.0%, 2.3%, and 4.2%, respectively, and symptoms were higher in people who were female, were older, were less educated, and had lower family income. People with fishery or related occupations compared to those with unrelated livelihoods and people residing in the vicinity of the oil band in the contaminated coastline showed additively increased symptom risks of PTS. Risk of suicidal ideation was predominantly increased in people with fishery or related occupations compared with those with unrelated livelihoods. CONCLUSIONS: Social supports, including compensation for income loss and community mental health programs, and longer follow-up studies are needed for residents in the communities affected by the Hebei Spirit oil spill.

Variation in the numbers of red blood cell units transfused at different medical institution types from 2006 to 2010 in Korea.

BACKGROUND: This study aimed at assessing the number of red blood cell (RBC) units transfused at different types of medical institution and examining the characteristics of transfusion recipients. METHODS: We calculated and compared the number of transfusion recipients, total RBC units transfused, and RBC units transfused per recipient. Study data were extracted from insurance benefits reimbursement claims for RBC units at the Health Insurance Review & Assessment Service from 2006 to 2010. RESULTS: Between 2006 and 2010, the number of recipients of RBC units increased from 298,049 to 376,445, the number of RBC units transfused increased from 1,460,799 to 1,841,695, and the number of RBC units transfused per recipient changed from 4.90 to 4.89. The number of recipients aged ≥65 yr increased from 133,833 (44.9%) in 2006 to 196,127 (52.1%) in 2010. The highest number of RBC units was transfused to patients with neoplastic diseases (31.9%) and diseases of the musculoskeletal system and connective tissue (14.4%). More than 80% of the total number of RBC units were transfused at tertiary and general hospitals. However, this composition rate was slightly decreasing, with the composition rate for hospitals increasing from 12.6% to 16.3%. CONCLUSIONS: This study revealed an increase in the number of RBC units transfused over a 5-yr period due to an increase in the number of transfused recipients, especially recipients aged ≥65 yr; moreover, the number of RBC units transfused differed based on medical institution type. These results provide fundamental data on RBC transfusions required for future research.

Polycyclic aromatic hydrocarbon-induced oxidative stress, antioxidant capacity, and the risk of lung cancer: a pilot nested case-control study.

AIM: We conducted a pilot nested case-control study to prospectively evaluate the effects of polycyclic aromatic hydrocarbons (PAH) exposure, antioxidant capacity, and oxidative stress on lung carcinogenesis. MATERIALS AND METHODS: Thirty-five patients with lung cancer and 140 age- and sex-matched controls were selected from a sub-cohort of the Korean Multi-center Cancer Cohort. PAH metabolites (1-hydroxypyrene and 2-naphthol), oxidative stress markers, and total antioxidant capacity (TAC) were assessed using urine samples collected at baseline. RESULTS: The levels of urinary PAH metabolites and oxidative stress were not different between cases and controls. Urinary 1-hydroxypyrene and 2-naphthol levels were significantly associated with urinary oxidative stress markers only in lung cancer cases. Individuals with low urinary TAC and high urinary oxidative stress levels had significantly higher risk of lung cancer compared to those with high urinary TAC and low urinary oxidative stress levels. CONCLUSION: Oxidative stress induced by PAH exposure and TAC may be important determinants for the susceptibility to lung cancer.

Trends in the incidence of hospitalized acute myocardial infarction and stroke in Korea, 2006-2010.

This study attempted to calculate and investigate the incidence of hospitalized acute myocardial infarction (AMI) and stroke in Korea. Using the National Health Insurance claim data, we investigated patients whose main diagnostic codes included AMI or stroke during 2006 to 2010. As a result, we found out that the number of AMI hospitalized patients had decreased since 2006 and amounted to 15,893 in 2010; and that the number of those with stroke had decreased since 2006 and amounted to 73,501 in 2010. The age-standardized incidence rate of hospitalized AMI, after adjustment for readmission, was 41.6 cases per 100,000-population in 2006, and had decreased to 29.4 cases in 2010 (for trend P < 0.001). In the case of stroke was estimated at 172.8 cases per 100,000-population in 2006, and had decreased to 135.1 cases in 2010 (for trend P < 0.001). In conclusion, the age-standardized incidence rates of both hospitalized AMI and stroke in Korea had decreased continuously during 2006 to 2010. We consider this decreasing trend due to the active use of pharmaceuticals, early vascular intervention, and the national cardio-cerebrovascular disease care project as the primary and secondary prevention efforts.

Cancer risk in diagnostic radiation workers in Korea from 1996–2002.

This study was aimed to examine the association between the effective radiation dose of diagnostic radiation workers in Korea and their risk for cancer. A total of 36,394 diagnostic radiation workers (159,189 person-years) were included in this study; the effective dose and cancer incidence were analyzed between the period 1996 and 2002. Median (range) follow-up time was 5.5 (0.04-7) years in males and 3.75 (0.04-7) years in females. Cancer risk related to the average annual effective dose and exposure to more than 5 mSv of annual radiation dose were calculated by the Cox proportional hazard model adjusted for occupation and age at the last follow-up. The standardized incidence ratio of cancer in radiation workers showed strong healthy worker effects in both male and female workers. The relative risk of all cancers from exposure of the average annual effective dose in the highest quartile (upper 75% or more of radiation dose) was 2.14 in male workers (95% CI: 1.48-3.10, p-trend: <0.0001) and 4.43 in female workers (95% CI: 2.17-9.04, p-trend: <0.0001), compared to those in the lower three quartiles of radiation exposure dose (less than upper 75% of radiation dose). Cancer risks of the brain (HR: 17.38, 95% CI: 1.05-287.8, p-trend: 0.04) and thyroid (HR: 3.88, 95% CI: 1.09-13.75, p-trend: 0.01) in female workers were significantly higher in the highest quartile group of radiation exposure compared to those in the lower three quartiles, and the risk of colon and rectum cancers in male workers showed a significantly increasing trend according to the increase of the average annual radiation dose (HR: 2.37, 95% CI: 0.99-5.67, p-trend: 0.02). The relative risk of leukemia in male workers and that of brain cancer in female workers were significantly higher in the group of people who had been exposed to more than 5 mSv/year than those exposed to less than 5 mSv/year (HR: 11.75, 95% CI: 1.08-128.20; HR: 63.11, 95% CI: 3.70-1,075.00, respectively). Although the present study involved a relatively young population and a short follow-up time, statistically significant increased risks of some cancers in radiation workers were found, which warrants a longer follow-up study and more intensive protective measures in this population.

Influenza-related mortality among adults aged 25-54 years with AIDS in South Africa and the United States of America.

BACKGROUND: Data are limited on human immunodeficiency virus (HIV)-associated influenza burden in sub-Saharan Africa and the impact of highly active antiretroviral therapy (HAART). We compared influenza-related mortality in adults with AIDS in South Africa and the United States in the pre-HAART era and evaluated mortality trends after HAART introduction in the United States. METHODS: Monthly all-cause and pneumonia and influenza (P&I) mortality rates were compiled for adults with AIDS aged 25-54 years in South Africa (1998-2005) and the United States (pre-HAART era, 1987-1994; HAART era, 1997-2005). We estimated influenza-related deaths as excess mortality above a model baseline during influenza epidemic periods. Influenza-related mortality rates in adults with AIDS were compared with rates for age peers in the general population and adults ≥65 years old. RESULTS: In the United States before HAART, influenza-related mortality rates in adults with AIDS were 150 (95% confidence interval [CI], 49-460) and 208 (95% CI, 74-583) times greater than in the general population for all-cause and P&I deaths, respectively, and 2.5 (95% CI, 0.9-7.2) and 4.1 (95% CI, 1.4-13) times higher than in elderly adults. After HAART introduction , influenza-related mortality in adults with AIDS dropped 3-6-fold but remained elevated compared with the general population (all-cause relative risk [RR], 44 [95% CI, 16-121]); P&I RR, 73 [95% CI, 47-113]). Influenza-related mortality in South African adults with AIDS in recent years was similar to that in the United States in the pre-HAART era. CONCLUSIONS: Adults with AIDS experience substantially elevated influenza-associated mortality, which declines with widespread HAART introduction but does not disappear. These data support increased access to HAART and influenza vaccination for HIV-infected adults.

Utility of fractional exhaled nitric oxide (F(E)NO) measurements in diagnosing asthma.

BACKGROUND: To facilitate the use of fractional exhaled nitric oxide (F(E)NO) as a clinical test, F(E)NO measurements need more clarification. AIM: We sought to evaluate the yield of F(E)NO measurement for the diagnosis of asthma and identify the determinants of F(E)NO in children. METHODS: Two hundred forty five consecutive steroid-naïve patients aged 8-16 years with symptoms suggestive of asthma were included. Children were evaluated using F(E)NO measurements, questionnaires, skin prick tests, spirometries, and methacholine challenge tests. RESULTS: Asthma was diagnosed in 167 children. The sensitivity, specificity, and positive (PPV) and negative predictive values (NPV) of F(E)NO measurements for the diagnosis of asthma at the best cutoff value of 22 ppb were 56.9%, 87.2%, 90.5%, and 48.6%, respectively. At a cutoff value of 42 ppb, specificity and PPV were all 100% but at the cost of very low sensitivity (23.4%) and NPV (37.9%). Both atopy and asthma were identified as independent risk factors associated with high F(E)NO. The association of asthma with high F(E)NO was found only in atopic children because F(E)NO was low in non-atopic children regardless of asthma status. Although highest F(E)NO was observed in atopic asthmatic patients, 28% of these patients had F(E)NO values lower than 22 ppb. CONCLUSION: Atopic asthmatic patients with low F(E)NO values and non-atopic asthmatic patients were responsible for false-negative cases that might contribute to low sensitivity of F(E)NO measurements in diagnosing asthma. High specificity of F(E)NO measurements may help identify patients with atopic asthma among subjects with respiratory symptoms.

The effect of volatile fatty acids as a sole carbon source on lipid accumulation by Cryptococcus albidus for biodiesel production.

The use of volatile fatty acids (VFAs) for microbial lipid accumulation was investigated in flask cultures of Cryptococcus albidus. The optimum culture temperature and pH were 25°C and pH 6.0, respectively, and the highest lipid content (27.8%) was obtained with ammonia chloride as a nitrogen source. The lipid yield coefficient on VFAs was 0.167 g/g of C. albidus with a VFAs (acetic, propionic, butyric acids) ratio of 8:1:1, which was in good agreement with a theoretically predicted lipid yield coefficient of the VFAs as a carbon source. The major fatty acids of the lipids accumulated by C. albidus were similar to those of soybean oil and jatropha oil. A preliminary cost analysis shows that VFAs-based biodiesel production is competitive with current palm and soybean based biodiesels. Further process development for lower aeration cost and higher lipid yield will make this process more economical.

Multi-stage high cell continuous fermentation for high productivity and titer.

We carried out the first simulation on multi-stage continuous high cell density culture (MSC-HCDC) to show that the MSC-HCDC can achieve batch/fed-batch product titer with much higher productivity to the fed-batch productivity using published fermentation kinetics of lactic acid, penicillin and ethanol. The system under consideration consists of n-serially connected continuous stirred-tank reactors (CSTRs) with either hollow fiber cell recycling or cell immobilization for high cell-density culture. In each CSTR substrate supply and product removal are possible. Penicillin production is severely limited by glucose metabolite repression that requires multi-CSTR glucose feeding. An 8-stage C-HCDC lactic acid fermentation resulted in 212.9 g/L of titer and 10.6 g/L/h of productivity, corresponding to 101 and 429% of the comparable lactic acid fed-batch, respectively. The penicillin production model predicted 149% (0.085 g/L/h) of productivity in 8-stage C-HCDC with 40 g/L of cell density and 289% of productivity (0.165 g/L/h) in 7-stage C-HCDC with 60 g/L of cell density compared with referring batch cultivations. A 2-stage C-HCDC ethanol experimental run showed 107% titer and 257% productivity of the batch system having 88.8 g/L of titer and 3.7 g/L/h of productivity. MSC-HCDC can give much higher productivity than batch/fed-batch system, and yield a several percentage higher titer as well. The productivity ratio of MSC-HCDC over batch/fed-batch system is given as a multiplication of system dilution rate of MSC-HCDC and cycle time of batch/fed-batch system. We suggest MSC-HCDC as a new production platform for various fermentation products including monoclonal antibody.

Elevated influenza-related excess mortality in South African elderly individuals, 1998-2005.

BACKGROUND: Although essential to guide control measures, published estimates of influenza-related seasonal mortality for low- and middle-income countries are few. We aimed to compare influenza-related mortality among individuals aged ≥65 years in South Africa and the United States. METHODS: We estimated influenza-related excess mortality due to all causes, pneumonia and influenza, and other influenza-associated diagnoses from monthly age-specific mortality data for 1998-2005 using a Serfling regression model. We controlled for between-country differences in population age structure and nondemographic factors (baseline mortality and coding practices) by generating age-standardized estimates and by estimating the percentage excess mortality attributable to influenza. RESULTS: Age-standardized excess mortality rates were higher in South Africa than in the United States: 545 versus 133 deaths per 100,000 population for all causes (P<.001) and 63 vs 21 deaths per 100,000 population for pneumonia and influenza (P=.03). Standardization for nondemographic factors decreased but did not eliminate between-country differences; for example, the mean percentage of winter deaths attributable to influenza was 16% in South Africa and 6% in the United States (P<.001). For all respiratory causes, cerebrovascular disease, and diabetes, age-standardized excess death rates were 4-8-fold greater in South Africa than in the United States, and the percentage increase in winter deaths attributable to influenza was 2-4-fold higher. CONCLUSIONS: These data suggest that the impact of seasonal influenza on mortality among elderly individuals may be substantially higher in an African setting, compared with in the United States, and highlight the potential for influenza vaccination programs to decrease mortality.

Influence of NQO1, ALDH2, and CYP2E1 genetic polymorphisms, smoking, and alcohol drinking on the risk of lung cancer in Koreans.

OBJECTIVES: We investigated the association of genetic polymorphisms of NQO1, ALDH2, CYP2E1, and the combined genotype of these genes on lung cancer risk, and also evaluated the association after stratification by cumulative smoking amounts and alcohol drinking levels. METHODS: The case-control study was performed in 387 lung cancer patients and 387 age- and sex-matched cancer-free controls. Direct interview was conducted and the genotypes of NQO1, ALDH2, and CYP2E1 were investigated using PCR-RFLP or 5'-nuclease activity assay. RESULTS: The proportion of individuals with occupational history of mining was significantly higher in cases than in controls. The risk of lung cancer was significantly lower in light-drinkers (<108 g/week) than non-drinkers. The NQO1 Pro/Ser + Ser/Ser genotype showed an increased risk for lung cancer with a marginal significance (OR = 1.35, 95% CI = 0.99-1.86) compared with NQO1 Pro/Pro genotype. In heavy-smokers, the combination of NQO1 Pro/Ser + Ser/Ser and CYP2E1 c1/c1 genotype was associated with a significantly increased risk for lung cancer (OR = 2.25, 95% CI = 1.14-4.43) compared with those of NQO1 Pro/Pro and CYP2E1 c1/c2 + c2/c2 genotype. We found a significant interaction between alcohol drinking level and the CYP2E1 genotype (P = 0.0227). CONCLUSIONS: Our result suggests that the risk of lung cancer is affected by smoking, alcohol drinking, and the genetic polymorphism of NQO1. In particular, genetic polymorphisms for NQO1, CYP2E1, and ALDH2 synergistically with cumulative smoking amounts and alcohol drinking levels interact in the carcinogenesis of lung cancer in Koreans.

Ethanol-induced oxidative DNA damage and CYP2E1 expression in liver tissue of Aldh2 knockout mice.

Excessive alcohol consumption is associated with increased risks of many diseases including cancer. We evaluated oxidative DNA damage in Aldh2 +/+ and Aldh2 -/- mice after they had been subjected to acute ethanol exposure. Olive tail moment, which was measured using a comet assay, was not increased by ethanol treatment in both Aldh2 +/+ and Aldh2 -/- mice. However, after controlling for the effect of ethanol exposure, the Aldh2 genotype was a significant determinant for Olive tail moments. Although the ethanol treatment significantly increased the hepatic 8-OHdG generation in only Aldh2 +/+ mice, the level of 8-OHdG was the highest in Aldh2 -/- ethanol treated mice. The increase in the level of 8-OHdG was associated with hepatic expression of cytochrome P450 2E1 (CYP2E1). The levels of Olive tail moment and the hepatic 8-OHdG in the Aldh2 -/- control group were significantly higher than those of the Aldh2 +/+ control group. The level of CYP2E1 in liver tissue showed a similar pattern to those of the oxidative DNA damage markers. This study shows that acute ethanol consumption increases oxidative DNA damage and that expression of CYP2E1 protein may play a pivotal role in the induction of oxidative DNA damage. The finding that oxidative DNA damage was more intense in Aldh2 -/- mice than in Aldh2 +/+ mice suggests that ALDH2-deficient individuals may be more susceptible than wild-type ALDH2 individuals to ethanol-mediated liver disease, including cancer.

Aryl hydrocarbon receptor gene polymorphisms affect lung cancer risk.

To evaluate the role of genetic polymorphisms of AhR related to the carcinogen metabolism and cell proliferation, genotypes of three AhR polymorphisms Ex1+185A>G, IVS7+33T>G and Ex10+501G>A were determined in 616 lung cancer cases and 616 lung cancer-free controls. When the effect of each AhR allele on lung cancer risk was evaluated, any AhR genotype did not show the association with lung cancer risk. However, when haplotypes were composed of three AhR SNP sites, non-smokers with GGG haplotype (adjusted OR=1.7, 95% CI, 1.06-2.71) and smokers without GGG haplotype (adjusted OR=2.5, 95% CI, 1.64-3.74) showed significantly increased risk of lung cancer compared to non-smokers without GGG haplotype. Moreover, smokers with GGG haplotype showed the highest risk (adjusted OR=3.2, 95% CI, 2.10-4.74). Particularly, the synergistic effect between AhR haplotype and smoking was more apparent in squamous cell carcinoma (adjusted OR=6.1, 95% CI, 2.53-14.68). This result suggests that haplotypes of AhR gene play an important role in the development of lung cancer and there is a synergistic interaction between AhR gene and smoking for lung cancer risk.

[Effects of oxidative DNA damage and genetic polymorphism of the glutathione peroxidase 1 (GPX1) and 8-oxoguanine glycosylase 1 (hOGG1) on lung cancer].

OBJECTIVES: Oxidative DNA damage is a known risk factor of lung cancer. The glutathione peroxidase (GPX) antioxidant enzyme that reduces hydrogen peroxide and lipid peroxides plays a significant role in protecting cells from the oxidative stress induced by reactive oxygen species. The aim of this case-control study was to investigate effects of oxidative stress and genetic polymorphisms of the GPX1 genes and the interaction between them in the carcinogenesis of lung cancer. METHODS: Two hundreds patients with lung cancer and 200 age- and sex-matched controls were enrolled in this study. Every subject was asked to complete a questionnaire concerning their smoking habits and their environmental exposure to PAHs. The genotypes of the GPX1 and 8-oxoguanine glycosylase 1 (hOGG1) genes were examined and the concentrations of urinary 1-hydroxypyrene (1-OHP), 2-naphthol and 8-hydroxydeoxyguanosine (8-OH-dG) were measured. RESULTS: Cigarette smoking was a significant risk factor for lung cancer. The levels of urinary 8-OH-dG were higher in the patients (p < 0.001), whereas the urinary 1-OHP and 2-naphthol levels were higher in the controls. The GPX1 codon 198 polymorphism was associated with an increased risk of lung cancer. Individuals carrying the Pro/Leu or Leu/Leu genotype of GPX1 were at a higher risk for lung cancer (adjusted OR = 2.29). In addition, these individuals were shown to have high urinary 8-OH-dG concentrations compared to the individuals with the GPX1 Pro/Pro genotype. On the other hand, the polymorphism of the hOGG1 gene did not affect the lung cancer risk and the oxidative DNA damage. CONCLUSIONS: These results lead to a conclusion that individuals with the GPX1 Pro/Leu or Leu/Leu genotype would be more susceptible to the lung cancer induced by oxidative stress than those individuals with the Pro/Pro genotype.

[Effects of oxidative DNA damage induced by polycyclic aromatic hydrocarbons and genetic polymorphism of the paraoxonase-1 (PON1) gene on lung cancer].

OBJECTIVES: Polycyclic aromatic hydrocarbons (PAHs), which are risk factors for lung cancer, have been reported to induce oxidative DNA damage. The paraoxonase (PON) plays a significant role in the detoxification of a variety of organophosphorous compounds, with paraoxonase-1 (PON1) being one of the endogenous free-radical scavenging systems in the human body. The aim of this case-control study was to investigate the effects of PAH exposure, oxidative stress and the Q192R polymorphism of PON1 genes, and their interactions in the carcinogenesis of lung cancer. METHODS: One hundred and seventy seven lung cancer patients and 177 age- and sex-matched controls were enrolled in this study. Each subject was asked to complete a questionnaire concerning their smoking habits and environmental exposure to PAHs. The Q192R genotypes of the PON1 gene was examined, and the concentrations of urinary 1-hydroxypyrene (1-OHP), 2-naphthol and 8-hydroxydeoxyguanosine (8-OH-dG) measured. RESULTS: Cigarette smoking was found to be a significant risk factor for lung cancer. The urinary 8-OH-dG level was higher in the patients, whereas the urinary 1-OHP and 2-naphthol levels were higher in the controls. There was a significant correlation between the urinary levels of 8-OH-dG and 1-OHP in both the cases and controls. The PON1 polymorphism was associated with an increased risk of lung cancer. Individuals carrying the Q/Q genotype of the PON1 gene were found to be at higher risk of developing lung cancer. There was a significant correlation between the urinary levels of 8-OH-dG and 1-OHP in those with the PON1 Q/Q genotype. CONCLUSIONS: These results lead to the conclusion that PAHs would induce oxidative DNA damage, especially in individuals with the PON1 Q/Q genotype. Therefore, people with the PON1 Q/Q genotype would be more susceptible to lung cancer than those with the R/R or Q/R genotypes of the PON1 gene.

[Epidemiologic investigation on sporadic occurrence of shigellosis in a subcounty of Cheongwon County in Chungbuk Province in 2003].

OBJECTIVES: This study was undertaken to investigate the source of infection and mode of transmission of shigellosis, which occurred sporadically among residents and students in a subcounty of Cheongwon county, Chungbuk province, Korea, from June 4 to July 3 2003. METHODS: 692 subjects completed a questionnaire and provided a swab for microbiological examinations and 7 environmental specimens were examined for bacterial organisms. PFGE (pulsed-field gel electrophoresis) and fingerprinting were performed to find the genetic relationship among the temporally associated sporadic isolates. RESULTS: A total of 29 patients had symptoms consistent with the case definition, with 13 confirmed and 16 suspected cases. The frequency of diarrhea was 6 times or more a day (80.8%), with a duration of 1 to 4 days (88.5%) in most cases. The most common symptoms accompanying the diarrhea were fever (80.9%) followed by abdominal pain (76.9%), headache (65.4%), chill (61.5%), vomiting (46.2%) and tenesmus (15.4%). The epidemic curve was characteristic of a person-to-person transmission. The PFGE and fingerprinting demonstrated identical or similar DNA patterns among the 3 Shigella sonnei isolates (A51, A53 and A61 types) found in this outbreak. CONCLUSION: A genetically identical strain of S. sonnei was estimated to be the cause of this outbreak, and the mode of transmission was most likely person-to-person.