Increased Screening Rates for Thyroid Cancer Among Residents Living Near Nuclear Power Plants

Frequent screening for thyroid cancer has been suggested as a probable explanation for the observed high risk of thyroid cancer in nuclear power plant (NPP) areas. We aimed to compare thyroid cancer screening rates of residents living near NPPs to those of the general population. This study utilized data from two national survey-based studies in 2016 and in 2014, respectively, for residents (n = 1,200) living in administrative districts within 5 km of NPP sites as the interest group, and the general population (n = 228,712) including distant-living residents (n = 19,100) in administrative districts within 30 km of NPP sites as reference groups. We observed an increase in screening rates in residents near NPPs, which may lead to a higher possibility of thyroid cancer detection. Therefore, further epidemiological studies investigating radiation-induced thyroid cancer risk among residents near NPPs should be carefully designed and interpreted considering possible detection bias.

Trends in socioeconomic inequalities in obesity among Korean adolescents: the Korea Youth Risk Behavior Web-based Survey (KYRBS) 2006 to 2020

OBJECTIVES

This study investigated recent trends in the prevalence of obesity among Korean adolescents and explored socioeconomic disparities in obesity.

METHODS

This study used annual self-reported data on height, weight, and socioeconomic information from the Korea Youth Risk Behavior Web-based Survey from 2006 to 2020. With a 95.8% response rate, the sample consisted of 818,210 adolescents. Obesity prevalence was calculated according to 4 socioeconomic indicators (household income, father's educational attainment, mother's educational attainment, and urbanicity). Socioeconomic inequality was quantified using the relative index of inequality (RII).

RESULTS

The overall prevalence of obesity increased, doubling from 5.9% in 2006 to 11.7% in 2020. Boys and high school students showed a higher prevalence. The RIIs in household income and parental educational attainments significantly increased with time, indicating a growing inequality in obesity. Socioeconomic disadvantages had a greater influence on obesity among girls. The most recent RII values for boys were 1.25 for income, 1.79 for the father's education, and 1.45 for the mother's education, whereas the corresponding values for girls were 2.49, 3.17, and 2.62, respectively.

CONCLUSIONS

These findings highlight growing inequalities in adolescent obesity according to household income and parental educational attainments, especially for girls and middle schoolers.

Obesity, hypertension, diabetes mellitus, and hypercholesterolemia in Korean adults before and during the COVID-19 pandemic: a special report of the 2020 Korea National Health and Nutrition Examination Survey

OBJECTIVES

We investigated trends in obesity, hypertension, diabetes, and hypercholesterolemia before and during the coronavirus disease 2019 (COVID-19) pandemic in the Korean adult population.

METHODS

Data from 60,098 participants in the Korea National Health and Nutritional Examination Survey between 2011 and 2020 aged ≥19 were used. The age-standardized prevalence and annual percent changes (APCs) were calculated for obesity (body mass index ≥25 kg/m2), hypertension (systolic/diastolic blood pressure ≥140/90 mmHg or under treatment), diabetes (hemoglobin A1c ≥6.5%, fasting glucose ≥126 mg/dL, physician diagnosis, or under treatment), and hypercholesterolemia (total cholesterol ≥240 mg/dL or under treatment).

RESULTS

Over the past decade (2011-2020), the age-standardized APCs (95% confidence intervals) for obesity, hypertension, diabetes and hypercholesterolemia were 3.0% (2.1 to 3.8), 0.1% (-1.3 to 1.5), 1.5% (-1.0 to 4.0) and 8.0% (5.7 to 10.3), respectively, in men; and -0.2% (-1.5 to 1.2), -0.5% (-1.9 to 0.9), -0.1% (-2.3 to 2.2) and 5.9% (3.9 to 8.0), respectively, in women. In 2020 compared to the previous 3 years (2017-2019), obesity, hypertension, diabetes, and hypercholesterolemia increased in men (6.0, 1.8, 1.9, and 2.8%p, respectively), but an increase was not apparent in women (2.5, -1.1, 0.8, and 0.7%p, respectively).

CONCLUSIONS

An increase in major chronic diseases was observed in Korean adults, especially men, during the COVID-19 pandemic. In order to reduce the burden of cardiovascular and metabolic diseases in the future, effective intervention strategies need to be developed according to the characteristics of the target groups.

Circumferential Rim Augmentation Suture Around the Perimeniscal Capsule Decreases Meniscal Extrusion and Progression of Osteoarthritis in Rabbit Meniscus Root Tear Model

BACKGROUND

We recently analyzed the joint capsule adjacent to the medial meniscus and found that the perimeniscal joint capsule has collagen fiber orientation similar to that of circumferential meniscal fibers, potentially playing a role in preventing extrusion.

PURPOSE

To analyze the meniscal extrusion prevention potential of the circumferential rim augmentation suture around the perimeniscal capsule in a rabbit root tear model and analyze the biomechanical function in a porcine cadaveric knee.

STUDY DESIGN

Controlled laboratory study.

METHODS

Rabbit medial meniscus root tear models were divided into 3 experimental groups: root tear, root tear and suture repair, and root tear and circumferential rim augmentation suture. As for the circumferential rim augmentation suture procedure, a suture was placed to circumscribe the outer rim of the medial meniscus and passed through bone tunnels located at the tibial insertion of each root. After 4 and 8 weeks, meniscal extrusion was analyzed by micro-computed tomography, gross morphology, and histologic analysis of the medial femoral cartilage. For biomechanical analysis, porcine knees were divided into groups similar to rabbit experiments. Tibiofemoral contact parameters were assessed using a pressure mapping sensor system after applying a load of 200 N on the knee joint.

RESULTS

The root tear and circumferential rim augmentation suture group showed less meniscal extrusion, less gap within the tear site, and less cartilage degeneration compared with other groups after 4 and 8 weeks of surgery in the rabbit root tear model. Biomechanical analysis showed the root tear and circumferential rim augmentation suture group had larger contact area and lower peak contact pressure compared with root tear and root tear and suture repair groups.

CONCLUSION

The circumferential rim augmentation suture reduced the degree of meniscal extrusion while restoring meniscal function, potentially preventing progression of arthritis in a rabbit root tear model and porcine knee biomechanical analysis.

CLINICAL RELEVANCE

The circumferential rim augmentation suture may be a novel augmentation option during root tear treatment.

Socioeconomic inequality in precautions compliance and health behavior changes during COVID-19 outbreak: analysis of the Korean Community Health Survey 2020

OBJECTIVES

This study examined socioeconomic inequalities in compliance with precautions and health behavior changes during the coronavirus disease 2019 (COVID-19) outbreak using a representative Korean sample.

METHODS

This exploratory study utilized around 210,000 participants aged ≥25 years in the Korean Community Health Survey 2020. Socioeconomic status was measured with educational attainment and household income. Outcomes included non-compliance with 8 precaution measures and deterioration in 6 health behaviors. The relative inequality index (RII) was calculated to quantify the degree of inequality by education and income level. RII values >1.0 indicate that deprived people have a higher frequency of health problems, and RII values <1.0 conversely indicate a higher frequency of health problems in more advantaged groups.

RESULTS

People with lower education or income levels tended to have higher rates of non-compliance with COVID-19 safety precautions (RII range, 1.20 to 3.05). Lower education and income levels were associated with an increased smoking amount (RII=2.10 and 1.67, respectively) and sleep duration changes (RII=1.21 and 1.36, respectively). On the contrary, higher education and income levels were associated with decreased physical activity (RII=0.59 and 0.77, respectively) and increased delivery food consumption (RII=0.27 and 0.37, respectively). However, increased alcohol drinking was associated with lower education and income levels in younger men (RII=1.73 and 1.31, respectively), but with higher levels in younger women (RII=0.73 and 0.68, respectively).

CONCLUSIONS

Our findings suggest the need to develop customized strategies, considering the characteristics of the target population, to decrease the burden and impact of the COVID-19 outbreak.

Association between a family history of diabetes and carotid artery atherosclerosis in Korean adults

OBJECTIVES

Diabetes is a well-known risk factor for atherosclerosis, but the association between a family history of diabetes and atherosclerosis remains unknown. In this study, we assessed the association between a family history of diabetes and increased carotid intima-media thickness (IMT), a marker of subclinical atherosclerosis, in a middle-aged Korean population.

METHODS

This cross-sectional study included 3,974 community-dwelling adults (1,404 male and 2,570 female) aged 30-64 years from the Cardiovascular and Metabolic Diseases Etiology Research Center cohort. The presence of a family history of diabetes was assessed through face-to-face interviews using a standardized questionnaire. Carotid IMT was assessed using B-mode ultrasonography, and increased IMT was defined as a value in the top quartile of the IMT values of all participants. Multivariate logistic regression was used to evaluate independent associations between a family history of diabetes and increased IMT.

RESULTS

A family history of diabetes was significantly associated with increased carotid IMT (odds ratio, 1.23; 95% confidence interval, 1.03 to 1.48) after adjusting for sex; age; body mass index; systolic blood pressure; total cholesterol, triglyceride, and hemoglobin A1c levels; smoking; alcohol consumption; exercise; use of antidiabetic, antihypertensive, and antilipidemic drugs; and a family history of hypertension. The positive association remained significant after excluding participants with diabetes (odds ratio, 1.21; 95% confidence interval, 1.00 to 1.47).

CONCLUSIONS

A family history of diabetes was positively associated with increased carotid IMT, even in participants without diabetes. Therefore, information on a family history of diabetes may help identify individuals at high risk of atherosclerotic cardiovascular disease.

Association between socioeconomic status and longitudinal sleep quality patterns mediated by depressive symptoms

STUDY OBJECTIVES

We aimed to examine whether associations between socioeconomic status (SES) and longitudinal sleep quality patterns are mediated by depressive symptoms.

METHODS

We utilized data on 3347 participants in the Korean Genome and Epidemiology Study aged 40-69 years at baseline from 2001 to 2002 who were followed up for 16 years. A group-based modeling approach was used to identify sleep quality trajectories using the Pittsburgh Sleep Quality Index (years 2, 6, 8, 10, and 12). Educational attainment (college graduated or less), monthly household income (≥$2500 or less), and occupation (unemployed, manual labor, and professional labor) at baseline (year 0) were used for analyses. Depressive symptoms were assessed using Beck's Depression Inventory at year 4. Associations between SES and sleep quality patterns were examined using a multinomial logistic regression model. The mediation effect of depressive symptoms was further examined using PROC CAUSALMED.

RESULTS

We identified five distinct sleep quality trajectories: "normal-stable" (n = 1697), "moderate-stable" (n = 1157), "poor-stable" (n = 320), "developing to poor" (n = 84), and "severely poor-stable" (n = 89). Overall, associations between SES levels and longitudinal sleep patterns were not apparent after full adjustment for sociodemographic and lifestyle factors measured at baseline. Depressive symptoms, however, tended to fully mediate associations between SES levels and sleep quality patterns (odds ratio range for indirect effects of depressive symptoms: for education, 1.05-1.17; for income, 1.05-1.15).

CONCLUSION

A significant mediating role for depressive symptoms between SES levels and longitudinal sleep quality warrants consideration among mental healthcare professionals.

The association between psychological resilience and cognitive function in longitudinal data: Results from the community follow-up survey

BACKGROUND

The present study aimed to investigate the association between resilience and cognitive function of middle-aged Koreans in a longitudinal setting.

METHODS

We utilized the baseline and 5-year follow-up data from the Cardiovascular and Metabolic Diseases Etiology Research Center study. The final number of participants included in the analysis was 397 (108 men, 289 women, mean age 55.4 years) who had valid measurements of both baseline resilience and Mini-Mental State Estimation at follow-up. The resilient people at baseline were operationally defined as the people who had at least one negative experience in the Life Experience Survey without depression, which was defined as a Beck Depressive Inventory-Ⅱ score of 20 or above. Cognitive function was evaluated by the Korean version of the Mini-Mental State Examination in both surveys. A generalized linear model was applied after adjusting for confounders. The association between resilience and cognitive function was further analyzed using stratification by median age and education level.

RESULTS

At follow-up, only in men, the resilience group showed a higher MMSE level compared to the reference group (β = 1.3, p = 0.002). Stratified by median age, both the younger group (β = 1.2, SE = 0.5, p = 0.031) and the older group among men (β = 2.1, SE = 0.7, p = 0.0069) showed a positive association between resilience and cognitive functions. However, when stratified by education level, only the low-education group presented the association (β = 1.7, SE = 0.5, p = 0.002). In women, no significant results were found.

LIMITATION

This study had limited number of participants.

CONCLUSION

Resilience at baseline was associated with more well-preserved cognitive function at follow-up in men.

Association between psychological resilience and cognitive function in older adults: effect modification by inflammatory status

To examine the association between psychological resilience and cognitive function and investigate the role of acute inflammation as an effect modifier. Total 7535 people from the Cardiovascular and Metabolic Disease Etiology Research Center (CMERC), aged ≥ 50 years and residing in areas near Seoul, South Korea, were included in this cross-sectional analysis. Stressful life events in the past 6 months were gauged by the Life Experience Survey, and current depression symptoms were analyzed with the Beck Depression Inventory-II. Participants were categorized into the following four groups according to their past experience and depression status: reference, resilient, reactive depression, and vulnerable depression. Cognitive function was evaluated using the mini-mental state examination (MMSE). The level of high-sensitivity C-reactive protein (hsCRP) was measured from blood samples. A generalized linear model was used. Upon adjusting for socio-demographic factors, comorbidity, and lifestyle factors, the final model was stratified with the highest quartile of the hsCRP level by sex. Compared to the reference group, the resilient group showed higher MMSE, which was also significant in women (adj-β = 0.280, p-value < 0.001). Vulnerable depression group showed a significantly lower MMSE (adj-β =  − -0.997, p-value 0.002), especially in men. This pattern seemed to be limited to the low hsCRP subgroup. We provided evidence from the largest Korean population used to evaluate the association between psychological resilience and cognition, which was more prominent in low inflammatory status. Psychological resilience was associated with a lower likelihood of cognitive deficit in women. This pattern was modulated by inflammatory status.

Stressful life events and serum triglyceride levels: the Cardiovascular and Metabolic Diseases Etiology Research Center cohort in Korea

OBJECTIVES

Elevated serum triglyceride levels are a risk factor for developing cardiovascular disease. A number of studies have demonstrated a positive association between psychological stress and serum triglyceride levels. However, there is limited evidence regarding the impact of stressful life events (SLEs) on serum triglyceride levels in the healthy population. Therefore, we evaluated the independent association between SLEs and serum triglyceride levels in a middle-aged Korean population.

METHODS

We analyzed a sample of 2,963 people (aged 30-64 years; 36% men) using baseline data from the Cardiovascular and Metabolic Diseases Etiology Research Center (CMERC) cohort study. The Korean version of the Life Experience Survey questionnaire was used to measure the presence and positive/negative impact of SLEs. Hypertriglyceridemia was defined as a fasting serum triglyceride level of ≥ 150 mg/dL.

RESULTS

Of the 2,963 participants, 33.1% reported at least 1 SLE over the past 6 months and 24.8% had hypertriglyceridemia. Even after adjusting for potential confounders, the serum triglyceride level was significantly associated with the total number of SLEs in men (3.333 mg/dL per event; p= 0.001), but not in women (0.451 mg/dL per event, p= 0.338). Hypertriglyceridemia was also associated with having 4 or more SLEs with positive effects (odds ratio [OR], 2.57; 95% CI, 1.02 to 6.46) and 4 or more SLEs with negative effects (OR, 1.99; 95% CI, 1.16 to 3.41) in men.

CONCLUSIONS

Our findings suggest that SLEs may increase the risk of hypertriglyceridemia in middle-aged men.

Association between sleep duration and augmentation index in post-menopausal women: A moderating role of depressive symptoms

OBJECTIVES

Physiological and psychological changes, including sleep disturbance and mood changes, frequently occur in post-menopausal women. We explored associations between sleep duration/quality and arterial stiffness, as well as the moderating role of depressive symptoms, in post-menopausal women.

STUDY DESIGN

This cross-sectional study utilized data obtained from 1687 post-menopausal women in the Cardiovascular and Metabolic Diseases Etiology Research Center cohort study.

MAIN OUTCOME MEASURES

Self-reported sleep was classified into short (<6 h/day), normal, and long (≥ 8 h/day) sleep durations. Poor sleep quality was operationally defined using the fatigue-related Berlin questionnaire. Depressive symptoms were assessed using the Beck Depression Index-II (BDI-II). Arterial stiffness was evaluated using the augmentation index (AI) and the HEM-9000AI system. The associations between sleep and AI were examined using generalized linear models, followed by a path model to investigate whether depressive symptoms act as an effect modifier.

RESULTS

AI (%) values for participants with poor sleep quality were higher than those for participants with normal sleep quality (β=1.53, standard error [SE]=0.59, p = 0.009). Although overall sleep duration was not associated with AI values, the severity of depressive symptoms altered the association (p-for interaction=0.021). The magnitude of the positive association between sleep duration and AI was amplified in participants with higher BDI-II scores. In participants with severe depressive symptoms (BDI-II ≥20), a long sleep duration was significantly associated with elevated AI values (β=4.80, SE=1.56, p = 0.003) compared with those with a normal sleep duration.

CONCLUSION

In post-menopausal women, poor sleep quality appears to result in an increase in arterial stiffness, and depressive symptoms seem to modify the association between sleep duration and AI. This modifying role for mental health should be considered in the association between sleep and cardiovascular health in post-menopausal women.

Dose-Response Association between Smoking Cessation and Arterial Stiffness: The Cardiovascular and Metabolic Diseases Etiology Research Center (CMERC) Cohort

Background and Objectives

Cigarette smoking has been reported to be associated with arterial stiffness. However, the clinical relevance of smoking cessation on arterial stiffness is debatable. Thus, we evaluated whether smoking cessation is associated with arterial stiffness.

Methods

A total of 1,169 male participants aged 30–64 years with absence of cardiovascular diseases in 2013–2017 were selected from the Cardiovascular and Metabolic Disease Etiology Research Center cohort study. The subjects were classified into the following 5 groups based on self-reporting: non-smokers, former smokers (<1, 1 to <10, and ≥10, years after cessation), and current smokers. Arterial stiffness was assessed using the augmentation index (AIx). The radial artery AIx was obtained from the peripheral artery waveform. The association was explored cross-sectionally.

Results

The AIx of former smokers did not differ from that of non-smokers (p=0.089). However, after former smokers were stratified by duration of smoking cessation, we noted a linear trend according to the smoking status (p<0.001). Men who quit smoking <1 year ago showed an elevated AIx (β=3.94, standard error=1.54, p=0.011) as much as ones of current smokers (β=4.39, standard error=0.74, p<0.001), while those who quit more than a decade ago showed an AIx similar to that of non-smokers (β=0.35, standard error=0.82, p=0.670) after controlling covariates.

Conclusions

A dose-response association between smoking cessation and AIx was revealed, which implies the possibility of a reversible effect of smoking cessation on arterial stiffness. Therefore, our findings may motivate current smokers to modify their smoking habits to delay or reverse disease progression.

Comparison of self-reported and accelerometer-assessed measurements of physical activity according to socio-demographic characteristics in Korean adults

OBJECTIVES

Previous studies have shown relatively low correlations between self-reported and accelerometer-assessed physical activity (PA). However, this association differs by socio-demographic factors, and this relationship has not been fully investigated in the general population. Thus, we investigated the correlation between self-reported and accelerometer-assessed PA and whether it differed by demographic and socioeconomic factors among the Korean general population.

METHODS

This cross-sectional study included 623 participants (203 men and 420 women) aged 30 to 64 years, who completed a PA questionnaire and wore a wrist-worn accelerometer on the non-dominant wrist for 7 days. We examined the agreement for metabolic equivalent task minutes per week (MET-min/wk) between the 2 measures and calculated Spearman correlation coefficients according to demographic and socioeconomic factors.

RESULTS

The kappa coefficient between tertiles of self-reported and accelerometer-assessed total MET-min/wk was 0.16 in the total population, suggesting overall poor agreement. The correlation coefficient between the 2 measurements was 0.26 (p<0.001) in the total population, and the correlation tended to decrease with increasing age (p for trend <0.001) and depression scores (p for trend <0.001).

CONCLUSIONS

We found a low correlation between self-reported and accelerometer-assessed PA among healthy Korean adults, and the correlation decreased with age and depression score. When studying PA using accelerometers and/or questionnaires, age and depression need to be considered, as should differences between self-reported and accelerometer-assessed PA.

Electrokinetic injection techniques in microfluidic chips

The separation efficiency of a microfluidic chip is influenced to a significant degree by the flow field conditions within the injection microchannel. Therefore, an understanding of the physics of the flow within this channel is beneficial in the design and operation of such a system. The configuration of an injection system is determined by the volume of the sample plug that is to be delivered to the separation process. Accordingly, this paper addresses the design and testing of injection systems with a variety of configurations, including a simple cross, a double-T, and a triple-T configuration. This paper also presents the design of a unique multi-T injection configuration. Each injection system cycles through a predetermined series of steps, in which the electric field magnitude and distribution within the various channels is strictly manipulated, to effectuate a virtual valve. The uniquemulti-T configuration injection system presented within this paper has the ability to simulate the functions of the cross, double-T, and triple-T systems through appropriate manipulations of the electric field within its various channels. In other words, the proposed design successfully combines several conventional injection systems within a single microfluidic chip.

Flow-through sampling for electrophoresis-based microfluidic chips using hydrodynamic pumping

This work presents a novel electrophoretic microchip design which is capable of directly coupling with flow-through analyzers for uninterrupted sampling. In this device, a 3 mm wide sampling channel (SC) was etched on quartz substrate to create the sample inlet and outlet and the 75 microm wide electrophoretic channels were also fabricated on the same substrate. Pressure was used to drive the sample flow through the external tube into the SC and the flow was then split into outlet and electrophoretic channels. A gating voltage was applied to the electrophoretic channel to control the sample loading for subsequent separations and inhibit the sample leakage. The minimum gating voltage required to inhibit the sample leakage depended on the solution buffer and increased with the hydrodynamic flow-rate. A fluorescent dye mixture containing Rhodamine B and Cy3 was introduced into the sample stream at either a continuous or discrete mode via an on-line injection valve and then separated and detected on the microchip using laser-induced fluorescence. For both modes, the relative standard deviation of migration time and peak intensity for consecutive injections was determined to be below 0.6 and 8%, respectively. Because the SC was kept floating, the external sampling equipment requires no electric connection. Therefore, such an electrophoresis-based microchip can be directly coupled with any pressure-driven flow analyzers without hardware modifications. To our best knowledge, this is something currently impossible for reported electrophoretic microchip designs.

A disposable poly(methylmethacrylate)-based microfluidic module for protein identification by nanoelectrospray ionization-tandem mass spectrometry

The design, fabrication, and analytical use of a poly(methylmethacrylate) (PMMA)-based microfluidic module for nanoelectrospray ionization-tandem mass spectrometry (nano-ESI-MS/MS) were described. The microfluidic module can be mass-produced at low costs and used as a disposable device to generate nano-ESI-MS/MS signals for protein identification from low amounts of protein samples. Compared with commercially available nanospray capillary tips, the module gave comparable signal quality and also offered advantages in convenience and easiness of operation, permitting repeated usage, and disposability.

Plastic microchip electrophoresis for genetic screening: The analysis of polymerase chain reactions products of fragile X (CGG)n alleles

Clinical screening of abnormal chromosomes associated with fragile X syndrome (FXS) demands a high-throughput method including DNA sizing and detection of the amplified products. This study is to explore the use of polymer microchip electrophoresis for the analysis of polymerase chain reaction (PCR) products of fragile X (CGG)n alleles to facilitate a fast exclusion test of FXS. The sequences flanking the CGG-repeat of FMR1 gene was amplified by betaine-PCR and the amplified products were desalted and then analyzed by microchips which were fabricated on poly(methyl methacrylate) (PMMA) substrate. The PCR bands with more than six CGG-repeats in difference could be clearly distinguished in less than 3 min by microchip electrophoresis with a separation length of 6 cm. It was found that the signal was greatly enhanced with the use of both covalent (Cy5) and intercalating dye (TORRO-3), which has never been demonstrated before. We tested the method by reanalysis of twelve samples from males and six samples from females. For female samples with less than six repeat differences, Southern blotting method was performed to confirm or exclude the findings from microchips. It was found that the test results from all male and female samples show a 100% correlation between the microchip electrophoresis and the existing methods.

Establishment and characterization of chromosomal aberrations in human cholangiocarcinoma cell lines by cross-species color banding

Cholangiocarcinoma (CC), a malignant neoplasm of the biliary epithelium, is usually fatal because of difficulty in early diagnosis and lack of availability of effective therapy. Furthermore, little is known about the genetics and biology of CC. Only a few reports concerning cytogenetic studies of CC have been published, and few cell lines have been established. We recently established four CC cell lines, designated as SCK, JCK, Cho-CK, and Choi-CK, and report the first application of cross-species color banding (RxFISH) and multiple chromosome painting for the characterization of the chromosomal rearrangements of these CC cell lines. Each cell line had unique modal karyotypic characteristics and showed a variable number of numerical and structural clonal cytogenetic aberrations. Chromosomes 3, 6, 7, 8, 12, 14, 17, and 18 were commonly involved in structural abnormalities. Homogeneously staining regions were determined in SCK and JCK, and double minute chromosomes were found in Cho-CK. The chromosomal aberrations of the four CC cell lines were effectively analyzed by RxFISH and FISH with multiple chromosome painting probes. The nonrandom rearrangements suggest candidate regions for isolation of genes related to CC.

Establishment and characterization of chromosomal aberrations in human cholangiocarcinoma cell lines by cross-species color banding

Cholangiocarcinoma (CC), a malignant neoplasm of the biliary epithelium, is usually fatal because of difficulty in early diagnosis and lack of availability of effective therapy. Furthermore, little is known about the genetics and biology of CC. Only a few reports concerning cytogenetic studies of CC have been published, and few cell lines have been established. We recently established four CC cell lines, designated as SCK, JCK, Cho-CK, and Choi-CK, and report the first application of cross-species color banding (RxFISH) and multiple chromosome painting for the characterization of the chromosomal rearrangements of these CC cell lines. Each cell line had unique modal karyotypic characteristics and showed a variable number of numerical and structural clonal cytogenetic aberrations. Chromosomes 3, 6, 7, 8, 12, 14, 17, and 18 were commonly involved in structural abnormalities. Homogeneously staining regions were determined in SCK and JCK, and double minute chromosomes were found in Cho-CK. The chromosomal aberrations of the four CC cell lines were effectively analyzed by RxFISH and FISH with multiple chromosome painting probes. The nonrandom rearrangements suggest candidate regions for isolation of genes related to CC.

Decreased activity of hepatic uroporphyrinogen decarboxylase in sporadic porphyria cutanea tarda

To investigate the role of uroporphyrinogen decarboxylase in the pathogenesis of the sporadic form of porphyria cutanea tarda, we measured this enzyme in liver, erythrocytes and cultured skin fibroblasts, and also measured coproporphyrinogen oxidase and the total iron concentration in liver. The mean uroporphyrinogen decarboxylase activity was lower in liver from seven male patients (9.0 pmol of coproporphyrin per minute per milligram of protein) than in 12 controls, including seven with alcoholic liver disease (22.3 pmol per minute per milligram; P less than 0.05). Coproporphyrinogen oxidase activities were the same in each group. Liver iron concentrations were lower during remission, but uroporphyrinogen decarboxylase activities were not related to clinical activity for uroporphyrin excretion. Erythrocyte and fibroblast enzyme activities were the same as in normal subjects. A hepatic uroporphyrinogen decarboxylase defect is a prerequisite for the development of porphyria cutanea tarda, but other factors, which probably do not alter uroporphyrinogen decarboxylase activity, determine the clinical onset. In sporadic porphyria cutaneous tarda, the enzyme defect appears to be restricted to the liver.

Familial foveal retinoschisis

Three young women, offspring of a nonconsanguineous marriage of normal parents, manifested mild visual loss associated with a bilateral foveal dystrophy that resembled the macular involvement in juvenile sex-linked retinoschisis. Electrophysiologic and psychophysiologic tests showed less severe involvement than the gonosomal equivalent. An autosomal recessive inheritance is proposed.

Lymphosarcoma in Crohn's disease: report of a case

In a patient who had a family history of ulcerative colitis and colonic carcinoma, a jejunal lymphosarcoma developed four years after resection for Crohn's disease of the small intestine. It is suggested that the association of lymphosarcoma with Crohn's disease is more than a chance association.

Photoelectron microscopy: a new approach to mapping organic and biological surfaces

A general method of imaging organic and biological surfaces based on the photoelectric effect is reported. For the experiments, a photoelectron emission microscope was constructed. It is an ultrahigh vacuum instrument using electrostatic electron lenses, microchannel plate image intensifier, cold stage, hydrogen excitation source, and magnesium fluoride optics. The organic surfaces examined were grid patterns of acridine orange, fluorescein, and benzo(a)pyrene on a Butvar surface. A biological sample, sectioned rat epididymis, was also imaged by the new photoelectron microscope. Good contrast was obtained in these initial low magnification experiments. These data demonstrate the feasibility of mapping biological surfaces according to differences in ionization potentials of exposed molecules. A number of technical difficulties, such as the intensity of the excitation source, must be solved before high resolution experiments are practical. However, it is probable that this approach can be useful, even at low magnifications, in determination of the properties of organic and biological surfaces.

Prolapse of semilunar cusps as causes of aortic insufficiency

Among the various anatomic classes of aortic valvular insufficiency is that associated with prolapse of one or several cusps of the valve. A number of etiologic factors come into play, including intrinsic weakness or excessive cuspid tissue, trauma, infection, inadequate support of the aorta as in certain ventricular septal defects, and loss of commissural support from laceration of the ascending aorta. The latter condition may result from trauma, cystic medial necrosis, inflammation, or hypertension. The lacerated aorta may either be associated with typical dissecting aneurysm or there may be little intramural dissection of blood.

In some instances wherein prolapse of one or more cusps causes aortic insufficiency, the functional disturbance may be overcome by correcting the basic problem while preserving the natural aortic valve.

Colour vision in blue-cone 'monochromacy'

1. Atypical (blue cone) monochromats show two action spectra when tested by the increment threshold method of Stiles with ;central' fixation. One spectrum peaks near 450 nm and has the spectral characteristics of normal blue cones. The other resembles rhodopsin (pi(0)) modified slightly by photostable macular pigment.2. Under some circumstances such observers are dichromats. There is a neutral point (matched to Illuminant ;C') in the neighbourhood of 460-470 nm.3. The spectral colour matching functions using two primaries have been measured on three such subjects. They can be fit reasonably well, although imperfectly, by linear combinations of pi(0) and pi(1). The chromaticity co-ordinates have been calculated according to the convention of W. D. Wright and compared to the results predicted from pi(0) and pi(1). The comparison suggests that part of the imperfections of the colour matching function fit is due to prereceptor differences (e.g. macular pigment) between the blue-cone monochromats and the hypothetical pi(0), pi(1) observer.4. Colour matches made at high light levels continue to hold when the intensity of the field is reduced below the cone threshold.5. Therefore one of the visual pigments participating in the colour matches has an action spectrum which is not measurably different from that of the rod pigment rhodopsin.6. Increment threshold measurements show that the mechanism which has the rhodopsin action spectrum has the directional sensitivity of cones, not rods.7. Blue test threshold during dark adaptation after a full bleach follow a bipartite exponential recovery curve. The first exponential has a time constant of 1 min, the second 2 min. By comparing these curves to the increment thresholds it is possible to relate the first to the pi(1), the second to the pi(0) cones.8. Using a broad band blue gelatin filter in the measuring light of the retinal densitometer and studying the same retinal region tested in 7 it is possible to follow the regeneration of a pigment after a full bleach which has an exponential recovery with a time constant of 1.0 min. With a yellow green filter in the measuring light the exponential recovery observed after a full bleach has a time constant of 2.0 min.9. One of the two visual pigments participating in the colour matches resides in receptors which have the action spectrum, the directional sensitivity and probably the dark adaptation curve of normal blue cones.10. The other resides in receptors which have the action spectrum of normal rods but the directional sensitivity and the dark adaptation curve of normal red and green cones.

Type II hyperlipoproteinemia in mother and twins

A 36-year-old housewife with type II hyperlipoproteinemia became pregnant with twins. Although the pregnancy was uneventful, the serum triglycerides were elevated during the third trimester, the delivery, and early puerperium. The mother had no complications directly related to the pregnancy despite hypercholesterolemia, coronary atherosclerosis, and hypertension. Cord blood cholesterol and beta lipoprotein in both twins were greater than twice normal. Despite this genetic defect in lipid transport the twins have developed normally during their first year of life. Since lipids and lipoproteins do not cross the placental barrier, it is concluded that type II hyperlipoproteinemia may have been present at birth.

Correlation of vectorcardiogram and electrocardiogram with coronary arteriogram

One hundred patients with suspected coronary heart disease were studied by vectorcardiography (VCG), electrocardiography (ECG), and coronary arteriography. Twenty-eight patients had VCG evidence of anterior infarction; 26 of this group had severe narrowing or obstruction of the left anterior descending branch. Five did not have anterior infarction by ECG. Twenty-seven patients had VCG evidence of diaphragmatic infarction; 25 of this group had severe narrowing of the right coronary artery or the left circumflex branch or both. Six of the 27 did not have ECG evidence of diaphragmatic infarction. Twelve patients had VCG evidence of posterior infarction whereas it was detected by ECG in only two. Only six of the 12, however, had severe narrowing of the nutrient arteries to the posterobasal part of the myocardium. Thirteen patients with infarction had severe narrowing but not total obstruction of a coronary artery. On the other hand, 15 patients had total obstruction of a major coronary vessel without actual infarction.

Particle-Size Analysis of Valders Drift in Eastern Wisconsin

Analysis of the fraction of Late Wisconsin deposits less than 2 mm in diameter has shown a wide range in textural composition of glacial tills. Massive lake sediments were high in clay content and contained less sand than the till of the same textural class. Glaciofluvial and eolian deposits were loamy to sandy and sandy, respectively.