Conducting a national burden of disease study in South Korea: from past to present

South Korea has been measuring its own burden of disease since the early 2000s and has developed a methodology for its calculation. Since 2012, South Korea has been carrying out disease burden research through the Research and Development Project, supported by the Ministry of Health and Welfare. Because the Korean health insurance system covers the entire population of the country, the Korean National Burden of Disease (KNBD) study is based on individual claims data. Disease prevalence, incidence, and mortality rates, which are the epidemiologic indicators used to calculate burden of disease, are based on actual data, and the incidence-based approach is used for Years Lived with disability (YLD), Years of Life Lost (YLL), and Disability Adjusted Life Year (DALY). The KNBD study is conducted for 260 diseases and injuries and subdivided into sub-national levels. Disability weights (DW) are calculated to reflect the sociocultural characteristics of a disease. For cause-specific DWs, we conducted a self-administered web-based survey for medical doctors and students. Using a ranking method, we calculated cause-specific DWs. For this reason, KNBD study results cannot be directly compared with GBD results.

The major findings of the KNBD study are as follows. In Korea, the DALY rate (per 100,000 people) steadily increased for all income levels. The higher the income, the lower the burden of disease; low-income people had a higher burden of disease than high-income people. However, thyroid cancer, refraction and accommodation disorders had a high burden of disease in the high-income group. Growth in the YLD rate was faster than in the YLL rate. In 2016 the leading causes of disease burden were diabetes mellitus, low back pain, and chronic obstructive pulmonary disease.

We will present South Korea's disease burden calculation methodology and its results and share the efforts to calculate disease burden in other countries.

Augmentation of Butyrate-induced Differentiation of Human Hepatocyte by Cyclin E Over-expression

In mammalian cells, cellular differentiation into specific cell types is usually preceded by growth arrest. On the other hand, the induced differentiation may also be preceded by an enhanced G1–S transition of the cell cycle prior to the growth arrest. This suggests that an early increase in proliferation is in some way a prerequisite for subsequent differentiation. We therefore attempted to assess whether we could produce human hepatocytes with further differentiated functions by promoting G1-S transition in a butyrate-treated human hepatocyte cell line. A cyclin E-over-expressing cell line was established by transfecting human cyclin E cDNA. Upon butyrate treatment, the cyclin E-over-expressing cells exhibited a significantly increased albumin-secreting and ammonia-detoxifying capacity when compared to the control cells. In particular, the ornithine transcarbamylase activity was increased in these cells. Collectively, these results implicate that the cyclin E over-expression may augment the hepatocyte-specific functions during the butyrate-induced differentiation process of human hepatocytes by enhancing G1-S cell cycle transition.

Identification of aldo-keto reductase (AKR7A1) and glutathione S-transferase pi (GSTP1) as novel renal damage biomarkers following exposure to mercury

The kidney is one of the main targets for toxicity induced by xenobiotics. Sensitive detection of early impairment is critical to assess chemical-associated renal toxicity. The aim of this study was to identify potential nephrotoxic biomarkers in rat kidney tissues after exposure to mercury (Hg), a representative nephrotoxicant, and to evaluate these new biomarkers employing in vivo and in vitro systems. Mercuric chloride was administered orally to Sprague-Dawley rats for 2 weeks. Proteomic analysis revealed that aldo-keto reductase (AKR7A1) and glutathione S-transferase pi (GSTP1) were significantly elevated in kidney after Hg exposure. While the levels of conventional nephrotoxic clinical markers including blood urea nitrogen and serum creatinine were not elevated, the mRNA and protein levels of AKR7A1 and GSTP1 were increased upon Hg exposure in a dose-dependent manner. The increases in AKR7A1 and GSTP1 were also observed in rat kidneys after an extended exposure for 6 weeks to low-dose Hg. In in vitro rat kidney proximal tubular cells, changes in AKR7A1 and GSTP1 levels correlated well with the extent of cytotoxicity induced by Hg, cadmium, or cisplatin. AKR7A1 and GSTP1 were identified as new candidates for Hg-induced nephrotoxicity, suggesting that these biomarkers have potential for evaluating or predicting nephrotoxicity.

Novel strategy for a bispecific antibody: induction of dual target internalization and degradation

Activation of the extensive cross-talk among the receptor tyrosine kinases (RTKs), particularly ErbB family-Met cross-talk, has emerged as a likely source of drug resistance. Notwithstanding brilliant successes were attained while using small-molecule inhibitors or antibody therapeutics against specific RTKs in multiple cancers over recent decades, a high recurrence rate remains unsolved in patients treated with these targeted inhibitors. It is well aligned with multifaceted properties of cancer and cross-talk and convergence of signaling pathways of RTKs. Thereby many therapeutic interventions have been actively developed to overcome inherent or acquired resistance. To date, no bispecific antibody (BsAb) showed complete depletion of dual RTKs from the plasma membrane and efficient dual degradation. In this manuscript, we report the first findings of a target-specific dual internalization and degradation of membrane RTKs induced by designed BsAbs based on the internalizing monoclonal antibodies and the therapeutic values of these BsAbs. Leveraging the anti-Met mAb able to internalize and degrade by a unique mechanism, we generated the BsAbs for Met/epidermal growth factor receptor (EGFR) and Met/HER2 to induce an efficient EGFR or HER2 internalization and degradation in the presence of Met that is frequently overexpressed in the invasive tumors and involved in the resistance against EGFR- or HER2-targeted therapies. We found that Met/EGFR BsAb ME22S induces dissociation of the Met-EGFR complex from Hsp90, followed by significant degradation of Met and EGFR. By employing patient-derived tumor models we demonstrate therapeutic potential of the BsAb-mediated dual degradation in various cancers.

Population-based epidemiology of primary biliary cirrhosis in South Korea

BACKGROUND

As a rare disease, only a few population-based epidemiology studies of primary biliary cirrhosis (PBC) have been reported.

AIMS

To elucidate the nationwide prevalence, incidence, complications, fatality and direct medical costs of PBC in South Korea.

METHODS

The nationwide Health Insurance Review and Assessment Service claims data and Rare Intractable Disease registration data on PBC, identified with the International Classification of Diseases (ICD) 10 code of K74.3, were obtained from 2009 to 2013. Age- and gender-specific prevalence and incidence rates of PBC were calculated, and data on complications, comorbidities, prescribed drugs, therapeutic procedures and direct medical costs were analysed.

RESULTS

A total of 2824 patients over 20 years old with PBC were identified in 2009-2013 (female-to-male ratio 6.2, median age 57 years old). The average age- and sex-adjusted incidence from 2011 to 2013 was 8.57 per million per year, and the average age- and sex-adjusted prevalence from 2009 to 2013 was 47.50 per million population. About 10% of patients presented with complications such as ascites (10.3%), variceal bleeding (5.8%) and/or hepatocellular carcinoma (HCC) (1.3%). Liver transplantation was undertaken in 71 patients (2.5%) for 5 years. Case fatality was 2.2% and the transplantation-free survival was 95.4% for 5 years.

CONCLUSIONS

This is the first report on the nationwide epidemiology of primary biliary cirrhosis in South Korea, demonstrating lower incidence and prevalence rates than those of Western countries, but a considerable disease burden, representing at least 10% were complicated with decompensated cirrhosis or hepatocellular carcinoma requiring liver transplantation.

Efficacy and safety of teneligliptin, a dipeptidyl peptidase-4 inhibitor, combined with metformin in Korean patients with type 2 diabetes mellitus: a 16-week, randomized, double-blind, placebo-controlled phase III trial

The aim of the present study was to assess the efficacy and safety of teneligliptin in combination with metformin in Korean patients with type 2 diabetes mellitus who were inadequately controlled with metformin monotherapy. Patients [glycated haemoglobin (HbA1c) 7.0-10.0%, on stable metformin ≥1000 mg/day] were randomized 2 : 1 to receive 20 mg teneligliptin plus metformin (n = 136) or placebo plus metformin (n = 68). The primary endpoint was the change in HbA1c levels from baseline to week 16. The mean baseline HbA1c was 7.9% in the teneligliptin group and 7.8% in the placebo group. The differences between the teneligliptin and placebo groups regarding changes in HbA1c and fasting plasma glucose levels were -0.78 % and -1.24 mmol/l (22.42 mg/dl), respectively, at week 16. The incidence of adverse events was similar between the groups. The addition of teneligliptin once daily to metformin was effective and generally well tolerated in Korean patients with type 2 diabetes.

Rapid genotyping of Plasmodium vivax Pvs25 and Pv38 genes by using mismatch specific endonuclease

Mismatch specific endonuclease (MSE) method was used to detect natural polymorphisms in Pvs25 and Pv38 genes of Plasmodium vivax. Eighty seven patients with P. vivax were recruited in the Republic of Korea (ROK). Pvs25 and Pv38 genes were amplified by polymerase chain reaction (PCR), and the PCR amplicons were mixed with reference DNA sequences. Following the denaturation and gradual annealing, the product mixtures were cleaved by the MSE. Heteroduplex types were readily detected by gel electrophoresis, where extra bands with shorter sizes would appear from the cleavage. After MSE cleavage of 657- bp product from Pvs25 mixtures, three genotypes were detected, while Pv38 mixtures with 1220-bp products presented two genotypes in ROK isolates. After the MSE cleavage, the mismatched samples of Pvs25 and Pv38 were completely sequenced, and the results were in complete agreement with the MSE analyses. In conclusion, genotyping of Pvs25 and Pv38 with MSE cleavage could be a potential method for the high-throughput screening of the large field samples.

Synthetic lethal screening reveals FGFR as one of the combinatorial targets to overcome resistance to Met-targeted therapy

Met is a receptor tyrosine kinase that promotes cancer progression. In addition, Met has been implicated in resistance of tumors to various targeted therapies such as epidermal growth factor receptor inhibitors in lung cancers, and has been prioritized as a key molecular target for cancer therapy. However, the underlying mechanism of resistance to Met-targeting drugs is poorly understood. Here, we describe screening of 1310 genes to search for key regulators related to drug resistance to an anti-Met therapeutic antibody (SAIT301) by using a small interfering RNA-based synthetic lethal screening method. We found that knockdown of 69 genes in Met-amplified MKN45 cells sensitized the antitumor activity of SAIT301. Pathway analysis of these 69 genes implicated fibroblast growth factor receptor (FGFR) as a key regulator for antiproliferative effects of Met-targeting drugs. Inhibition of FGFR3 increased target cell apoptosis through the suppression of Bcl-xL expression, followed by reduced cancer cell growth in the presence of Met-targeting drugs. Treatment of cells with the FGFR inhibitors substantially restored the efficacy of SAIT301 in SAIT301-resistant cells and enhanced the efficacy in SAIT301-sensitive cells. In addition to FGFR3, integrin β3 is another potential target for combination treatment with SAIT301. Suppression of integrin β3 decreased AKT phosphorylation in SAIT301-resistant cells and restored SAIT301 responsiveness in HCC1954 cells, which are resistant to SAIT301. Gene expression analysis using CCLE database shows that cancer cells with high levels of FGFR and integrin β3 are resistant to crizotinib treatment, suggesting that FGFR and integrin β3 could be used as predictive markers for Met-targeted therapy and provide a potential therapeutic option to overcome acquired and innate resistance for the Met-targeting drugs.

Role of pancreatic β-cell death and cell death-associated inflammation in diabetes

Pancreatic β-cell death of various types has diverse and important roles in the pathogenesis of both type 1 (T1D) and type 2 (T2D) diabetes. The most widely recognized types of β-cell death in diabetes are apoptosis (type 1 programmed cell death) and necrosis. Apoptosis of β-cells is the key and final step in the development of T1D and contributes to β-cell failure or dysfunction in T2D. In the course of natural T1D, apoptotic β-cells undergoing secondary necrosis probably due to their defective clearance by phagocytes, may be involved in the initiation and development of the disease. Recently, autophagy (type 2 programmed cell death) is proposed as a third type of cell death and is being recognized as having certain roles in the prevention and execution of β-cell death, depending on the cellular context. Moreover, as dying β-cells are routinely exposed to the immune system, β-cell death could also affect the development of diabetes through regulation of inflammation or immune response. In this review, we describe the role of various types of pancreatic β-cell death in the development of T1D and T2D. We also discuss the role of dying β-cells in the control of inflammation which contributes to the pathogenesis of diabetes.

Efficacy and safety of canagliflozin monotherapy in subjects with type 2 diabetes mellitus inadequately controlled with diet and exercise

AIMS

Canagliflozin is a sodium glucose co-transporter 2 inhibitor in development for type 2 diabetes mellitus (T2DM). The efficacy and safety of canagliflozin were evaluated in subjects with T2DM inadequately controlled with diet and exercise.

METHODS

In this 26-week, randomized, double-blind, placebo-controlled, phase 3 trial, subjects (N = 584) received canagliflozin 100 or 300 mg or placebo once daily. Primary endpoint was the change from baseline in haemoglobin A1c (HbA1c) at week 26. Secondary endpoints included the proportion of subjects achieving HbA1c < 7.0%; change from baseline in fasting plasma glucose (FPG), 2-h postprandial glucose (PPG) and systolic blood pressure (BP); and percent change in body weight, high-density lipoprotein cholesterol (HDL-C) and triglycerides. Adverse events (AEs) were recorded throughout the study.

RESULTS

At week 26, HbA1c was significantly reduced from baseline with canagliflozin 100 and 300 mg compared with placebo (-0.77, -1.03 and 0.14%, respectively; p < 0.001 for both). Both canagliflozin doses significantly decreased FPG, 2-h PPG, body weight and systolic BP (p < 0.001 for all), and increased HDL-C compared with placebo (p < 0.01 for both). Overall incidences of AEs were modestly higher with canagliflozin versus placebo; rates of serious AEs and AE-related discontinuations were low and similar across groups. Incidences of genital mycotic infections, urinary tract infections and osmotic diuresis-related AEs were higher with canagliflozin; these led to few discontinuations. The incidence of hypoglycaemia was low across groups.

CONCLUSION

Canagliflozin treatment improved glycaemic control, reduced body weight and was generally well tolerated in subjects with T2DM inadequately controlled with diet and exercise.

Development of a fibre-optic dosemeter to measure the skin dose and percentage depth dose in the build-up region of therapeutic photon beams

In this study, a fibre-optic dosemeter (FOD) using an organic scintillator with a diameter of 0.5 mm for photon-beam therapy dosimetry was fabricated. The fabricated dosemeter has many advantages, including water equivalence, high spatial resolution, remote sensing and real-time measurement. The scintillating light generated from an organic-dosemeter probe embedded in a solid-water stack phantom is guided to a photomultiplier tube and an electrometer via 20 m of plastic optical fibre. Using this FOD, the skin dose and the percentage depth dose in the build-up region according to the depths of a solid-water stack phantom are measured with 6- and 15-MV photon-beam energies with field sizes of 10 × 10 and 20 × 20 cm(2), respectively. The results are compared with those measured using conventional dosimetry films. It is expected that the proposed FOD can be effectively used in radiotherapy dosimetry for accurate measurement of the skin dose and the depth dose distribution in the build-up region due to its high spatial resolution.

Efficacy and safety of glimepiride/metformin sustained release once daily vs. glimepiride/metformin twice daily in patients with type 2 diabetes

AIMS

The study investigated the clinical equivalence in reducing haemoglobin A1c (A1C) between glimepiride/metformin sustained release (GM-SR) 2/500 mg, a fixed-dose combination, once daily and glimepiride/metformin (GM) 1/250 mg, a fixed-dose combination, twice daily in patients with type 2 diabetes (T2D).

METHODS

A multicentre, randomised, double-blind, double-dummy study was conducted in 14 hospitals in Korea. Inclusion criteria were age 30-75 years, T2D diagnosis no longer than 10 years previously, A1C between 7% and 10%, and body mass index <40 kg/m(2) . A total of 207 subjects were randomised into the GM-SR group (n=101) or the GM group (n=106). Participants were assessed at baseline, 8 weeks and 16 weeks after treatment.

RESULTS

After 16 weeks treatment, no difference in baseline-adjusted changes of A1C (primary efficacy variable) was observed between the two groups (-0.59% for GM-SR group vs. -0.61% for GM group, 95% CI: -0.17 to 0.21; p=0.84). In addition, there were no significant differences in secondary efficacy parameters between the two groups, including changes in A1C up to week 8, changes in fasting plasma glucose (FPG) and 2-h-postprandial plasma glucose up to week 8 and week 16, response rate, drug compliance and hypoglycaemic events. However, there was a difference in baseline-adjusted changes of FPG between the two groups (-1.01 mmol/l for GM-SR group vs. -1.52 mmol/l for GM group, p=0.01 in the intention to treat set).

CONCLUSIONS

GM-SR 2/500 mg once daily was as effective as GM 1/250 mg twice daily in lowering A1C. In addition, no difference was noted in hypoglycaemic events between the two groups.

Differentiation of early hepatocellular carcinoma from benign hepatocellular nodules on gadoxetic acid-enhanced MRI

OBJECTIVE

To test new diagnostic criteria for the discrimination of early hepatocellular carcinoma (HCC) from benign hepatocellular nodules on gadoxetic acid-enhanced MRI (Gd-EOB-MRI).

METHODS

We retrospectively analysed 34 patients with 29 surgically diagnosed early HCCs and 31 surgically diagnosed benign hepatocellular nodules. Two radiologists reviewed Gd-EOB-MRI, including diffusion-weighted imaging (DWI), and the signal intensity at each sequence, presence of arterial enhancement and washout were recorded. We composed new diagnostic criteria based on the lesion size and MRI findings, and then the diagnostic performance was compared with that of conventional imaging criteria with logistic regression and a generalised estimating equation method.

RESULTS

A size cut-off value (≥1.5 cm diameter) and MRI findings of T(1) hypointensity, T(2) hyperintensity, DWI hyperintensity on both low and high b-value images (b=50 and 800 s mm(-2), respectively), arterial enhancement, late washout and hepatobiliary hypointensity were selected as the diagnostic criteria. When lesions were considered malignant if they satisfied three or more of the above criteria, the sensitivity was significantly higher than when making a diagnosis based on arterial enhancement and washout alone (58.6% vs 13.8%, respectively; p=0.0002), while the specificity was 100.0% for both criteria.

CONCLUSION

Our new diagnostic criteria on Gd-EOB-MRI may help to improve the discrimination of early HCC from benign hepatocellular nodules.

Long-term efficacy of entecavir therapy in chronic hepatitis B patients with antiviral resistance to lamivudine and adefovir

No studies have reported the long-term effects of entecavir switching in patients with multidrug resistance who developed resistance after lamivudine/adefovir sequential therapy. We evaluated the efficacy of 96 weeks of entecavir therapy in patients with resistance to lamivudine/adefovir sequential therapy. In total, 33 patients with chronic hepatitis B virus (HBV) infection with evidence of active viral replication (HBV DNA levels ≥ 10(5) copies/mL) or a history of treatment failure to lamivudine/adefovir sequential therapy between April 2007 and July 2009 were treated with entecavir (1.0 mg daily) for at least 48 weeks. The rates of alanine transaminase (ALT) normalization and HBV DNA negativity were 66.7% (14/21) and 24.2% (8/33) at 48 weeks, respectively. The initial HBV DNA level was the only factor that was inversely associated with serum HBV DNA negativity after 48 weeks of entecavir therapy (P < 0.023). At 96 weeks, the rates of ALT normalization and HBV DNA negativity were 77.8% (7/9) and 16.7% (3/18), respectively. Viral breakthrough occurred in 21.2% (7/33) and 78.9% (15/19) of patients at 48 and 96 weeks, respectively. Patients who achieved a HBV DNA level of <4 log(10) copies/mL at 48 weeks maintained a similar HBV DNA level and a normal ALT level until 96 weeks. Entecavir monotherapy for 96 weeks was not efficacious for patients with lamivudine/adefovir-resistant HBV. The initial HBV DNA level was the only predictive factor for antiviral efficacy. However, patients who achieved a HBV DNA level of <4 log(10) copies/mL with a normal ALT level at 48 weeks should maintain, rather than stop, entecavir therapy.

Reactive oxygen species-dependent necroptosis in Jurkat T cells induced by pathogenic free-living Naegleria fowleri

Naegleria fowleri, a free-living amoeba, is the causative pathogen of primary amoebic meningoencephalitis in humans and experimental mice. N. fowleri is capable of destroying tissues and host cells through lytic necrosis. However, the mechanism by which N. fowleri induces host cell death is unknown. Electron microscopy indicated that incubation of Jurkat T cells with N. fowleri trophozoites induced necrotic morphology of the Jurkat T cells. N. fowleri also induced cytoskeletal protein cleavage, extensive poly (ADP-ribose) polymerase hydrolysis and lactate dehydrogenase (LDH) release. Although no activation of caspase-3 was observed in Jurkat T cells co-incubated with amoebae, intracellular reactive oxygen species (ROS) were strongly generated by NADPH oxidase (NOX). Pretreating cells with necroptosis inhibitor necrostatin-1 or NOX inhibitor diphenyleneiodonium chloride (DPI) strongly inhibited amoeba-induced ROS generation and Jurkat cell death, whereas pan-caspase inhibitor z-VAD-fmk did not. N. fowleri-derived secretory products (NfSP) strongly induced intracellular ROS generation and cell death. Necroptotic effects of NfSP were effectively inhibited by pretreating NfSP with proteinase K. Moreover, NfSP-induced LDH release and intracellular ROS accumulation were inhibited by pretreating Jurkat T cells with DPI or necrostatin-1. These results suggest that N. fowleri induces ROS-dependent necroptosis in Jurkat T cells.

Hepatocellular carcinoma in patients with chronic liver disease: a comparison of gadoxetic acid-enhanced MRI and multiphasic MDCT

AIM

To compare the diagnostic performances of gadoxetic acid-enhanced magnetic resonance imaging (MRI) and multiphasic multidetector computed tomography (MDCT) in the detection of hepatocellular carcinoma (HCC) in patients with chronic liver disease.

MATERIALS AND METHODS

Institutional review board approval was obtained for this study and informed consent was obtained from all patients. Fifty-one patients (43 men, eight women; age range 32-80 years) with 73 HCCs underwent gadoxetic acid-enhanced MRI and multiphasic MDCT. Two readers independently analysed each image in three separate reading sessions. The alternative free-response receiver operating characteristic (AFROC) method was used to analyse the diagnostic accuracy. Positive and negative predictive values and sensitivity were evaluated.

RESULTS

A total of 73 HCCs were detected in 51 patients. Although not significant (p>0.05), the areas under the receiver operating characteristic curves were 0.877 and 0.850 for MDCT, 0.918 and 0.911 for dynamic MRI, and 0.905 and 0.918 for combined interpretation of dynamic and hepatobiliary phase MR images. Differences in sensitivity, specificity, and positive and negative predictive values between the readers were not statistically significant (p>0.05). Combined interpretation of dynamic and hepatobiliary phase MRI images was more useful than MDCT in the detection of HCC lesions ≤1cm in diameter for one reader (p=0.043).

CONCLUSION

Gadoxetic acid-enhanced MRI and MDCT show similar diagnostic performances for the detection of HCC in patients with chronic liver disease. However, the combined interpretation of dynamic and hepatobiliary phase MRI images may improve diagnostic accuracy in the detection of HCC lesions ≤1cm in diameter.

Calpain mediates degradation of cytoskeletal proteins during Jurkat T-cell death induced by Entamoeba histolytica

Entamoeba histolytica is known to induce host cell death via activation of calpain and caspases. In this study, we investigated the specific proteases involved in the degradation of cytoskeletal proteins during Jurkat T-cell death induced by E. histolytica. Amoebic trophozoites induced marked degradation of paxillin, Cas, vimentin, vinculin and talin, as well as α- or β-spectrin, in Jurkat T cells. The cleavage effects of E. histolytica were strongly retarded by pretreatment with a calpain inhibitor, but not with a pan-caspase inhibitor. In addition, calpain knockdown with siRNA in Jurkat T cells effectively inhibited E. histolytica-induced PARP, paxillin, α-spectrin, β-spectrin and talin degradation, as compared to scrambled siRNA. These results suggest that calpain plays a crucial role in the cleavage of cytoskeletal proteins during cell death induced by E. histolytica.

ABCG2 polymorphisms, 34G>A and 421C>A in a Korean population: analysis and a comprehensive comparison with other populations

BACKGROUND AND OBJECTIVE

ABCG2, also known as Breast Cancer Resistance Peptide (BCRP) or mitoxantrone-resistant protein, is the second member of the G-family of ABC transporters. The frequencies of ABCG2 34G>A and 421C>A polymorphisms in a Korean population were assessed using a newly developed multiplex pyrosequencing method, and compared with the corresponding frequencies seen in other ethnic groups.

METHOD

We designed a multiplex pyrosequencing method to simultaneously detect ABCG2 421C>A and 34G>A polymorphisms and analysed the allele frequencies of these polymorphisms in 250 Korean subjects.

RESULTS

The results showed 100% concordance between single and multiplex pyrosequencing methods. We also validated the polymorphisms identified by pyrosequencing with a direct sequencing method using randomly selected samples. The allele frequencies of ABCG2 421C>A and 34G>A in the population tested were 0·298 and 0·190 respectively. The allele frequency of the 421C>A polymorphism is comparable to other Asian populations, including Japanese and Chinese. However, both frequencies are different from those of Caucasians and Africans.

CONCLUSIONS

The multiplex pyrosequencing method used to detect two ABCG2 polymorphisms concurrently is a rapid and reliable genotyping method for the detection of important ABCG2 genetic polymorphisms. The ABCG2 34G>A and 421C>A polymorphisms are frequently found in the Korean population. The frequencies are similar to those seen in other Asian populations including Japanese and Chinese, but very different to those of Caucasian and African-American populations.

Relative accuracy of CT and MRI in the differentiation of benign from malignant pancreatic cystic lesions

AIMS

To assess the diagnostic accuracies of multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) for differentiating benign from malignant lesions and suggesting the specific diagnoses for pancreatic cystic lesions, and to assess whether review of both MDCT and MRI is beneficial.

MATERIALS AND METHODS

Patients with various neoplastic and non-neoplastic pancreatic cystic lesions that were identifiable by biopsy or surgery, who underwent both MRI and MDCT (n=63), were retrospectively reviewed by three reviewers. The likelihood of malignancy was recorded on a five-point scale, and a specific diagnosis was given. ROC analysis was performed and the sensitivity, specificity for the characterization of malignancy, and the accuracy of specific diagnoses were calculated.

RESULTS

MDCT and MRI yielded comparable results for the characterization of malignancy (Az: 0.639, 0.735, 0.806 for MDCT and 0.732, 0.753, 0.792 for MRI, for each reviewer). The accuracies of specific diagnosis based on MDCT or MRI were 61.9 versus 55.6% for reviewer 1; 76.2 versus 76.2% for reviewer 2; and 65.1 versus 61.9% for reviewer 3. There was a trend toward better prediction of malignancy (Az: 0.787, 0.745, 0.849 for each reviewer), and better accuracy in suggesting a specific diagnosis (77.8, 73, and 73% for each reviewer) for MDCT+MRI over MDCT or MRI alone, although it was statistically significant for one reviewer in the comparison of MDCT versus MDCT+MRI for the prediction of malignancy, and MRI versus MDCT for suggesting a specific diagnosis.

CONCLUSIONS

MDCT and MRI have equivalent accuracy for characterizing pancreatic cystic lesions as benign or malignant, and suggesting a specific diagnosis. Combined review of MDCT and MRI was not significantly better but may have the potential to improve diagnostic accuracy in equivocal cases.

MRI findings of uncommon non-hepatocyte origin primary liver tumours with pathological correlation

The objective of this article was to illustrate the MRI findings of uncommon non-hepatocyte origin primary liver tumours, correlate them with the pathological features and discuss differential diagnoses. In conclusion, the MRI findings of uncommon benign and malignant non-hepatocyte-origin primary liver tumours vary. Awareness of characteristic MRI features can aid differential diagnosis and prevent unnecessary surgery.

Calpain-dependent cleavage of SHP-1 and SHP-2 is involved in the dephosphorylation of Jurkat T cells induced by Entamoeba histolytica

Host cell death induced by Entamoeba histolytica is an important mechanism for both host defence and microbial immune evasion during human amoebiasis. However, the signalling pathways underlying cell death induced by E. histolytica are not fully understood. This study investigated the involvement of the protein tyrosine phosphatases (PTPs) SHP-1 and SHP-2 in the dephosphorylation associated with E. histolytica-induced host cell death. Incubation with E. histolytica resulted in a marked decrease in protein tyrosine phosphorylation levels and degradation of SHP-1 or SHP-2 in Jurkat cells. Pre-treatment of cells with a calpain inhibitor, calpeptin, impeded the amoeba-induced dephosporylation and cleavage of SHP-1 or SHP-2. Additionally, inhibition of PTPs with phenylarsine oxide (PAO) attenuated Entamoeba-induced dephosphorylation and DNA fragmentation in Jurkat T cells. These results suggest that calpain-dependent cleavage of SHP-1 and SHP-2 may contribute to protein tyrosine dephosphorylation in Jurkat T cell death induced by E. histolytica.

Primary serous papillary carcinoma of the peritoneum mimicking pelvic actinomycosis: a case report and brief literature review

Primary serous papillary carcinoma of the peritoneum is a rare tumor, histologically similar to primary ovarian carcinoma. Pelvic CT and MRI are helpful to diagnose primary carcinoma of the peritoneum. We present a case of primary serous carcinoma of the peritoneum mimicking pelvic actinomycosis in a 59-year-old woman. Pelvic CT and MRI suggested pelvic actinomycosis. Exploratory laparotomy was performed to remove the mass and the diagnosis was confirmed by pathology. A subtotal hysterectomy, left salpingo-oophorectomy and omentectomy were performed. Histopathology examination revealed peritoneal carcinomatosis and primary serous carcinoma of the peritoneum. Pelvic CT and MRI were limited in their ability to differentiate inflammation, such as actinomycosis, from primary carcinoma of the peritoneum.

Effect of CYP3A5*3 genotype on serum carbamazepine concentrations at steady-state in Korean epileptic patients

BACKGROUND AND OBJECTIVE

Carbamazepine (CBZ) is metabolized mainly by the CYP3A family of enzymes, which includes CYP3A4 and CYP3A5. Several studies have suggested that the CYP3A5*3 genotype influences the pharmacokinetics of CYP3A substrates. The present study aimed to assess the effect of the CYP3A5*3 genotype on serum concentration of CBZ at the steady-state in Korean epileptic patients.

METHOD

The serum concentrations of CBZ in 35 Korean epileptic patients were measured and their CYP3A5 genotype was determined. Fourteen patients were CYP3A5 expressors (two for CYP3A5*1/*1 and 12 for CYP3A5*1/*3) and 21 patients were CYP3A5 non-expressors (CYP3A5*3/*3). Dose-normalized concentrations (mean +/- SD) of CBZ were 9.9 +/- 3.4 ng/mL/mg for CYP3A5 expressors and 13.1 +/- 4.5 ng/mL/mg for CYP3A5 non-expressors (P = 0.032). The oral clearance of CBZ was significantly higher in CYP3A5 non-expressors than that of CYP3A5 expressors (0.056 +/-0.017 L/h/kg vs. 0.040 +/- 0.014 L/h/kg, P = 0.004). The CYP3A5 genotype affected the CBZ concentrations in Korean epileptic patients and is a factor that may contribute to inter-individual variability in CBZ disposition in epileptic patients.

Pancreatic ductal adenocarcinoma with intratumoral cystic lesions on MRI: correlation with histopathological findings

The purpose of this study was to evaluate intratumoral cystic lesions of pancreatic ductal adenocarcinoma (PDAC) depicted on MRI, and to correlate these cystic lesions with their histopathological findings. This study included 12 patients (7 males and 5 females; mean age, 59 years) with intratumoral cystic lesions of PDAC detected on a retrospective MRI review. We reviewed the histopathological findings of the cystic lesions within PDACs and analysed the MRI findings, focusing on the appearance of the intratumoral cystic lesions, i.e. the size, number, margin and intratumoral location, and on the ancillary findings of PDAC, i.e. peripancreatic infiltration, upstream pancreatic duct dilatation and distal parenchymal atrophy. Intratumoral cystic lesions were classified as neoplastic mucin cysts (n = 7, 58%) or cystic necrosis (n = 5, 42%) according to the histopathological findings; they ranged in greatest dimension from 0.5 cm to 3.4 cm (mean, 1.7 cm). Seven patients had only one cystic lesion each, while the remaining five had multiple cystic lesions. Most of the neoplastic mucin cysts had smooth margins (n = 6, 86%) and eccentric locations (n = 6), whereas most cystic necroses had irregular margins (n = 4, 80%) and centric locations (n = 4). The most common ancillary findings of PDAC were peripancreatic infiltration, distal pancreatic atrophy and upstream pancreatic duct dilatation (92%, 75% and 58%, respectively). The intratumoral cystic lesions of PDACs on MRI were classified as either neoplastic mucin cysts with smooth margins and eccentric locations or cystic necroses with irregular margins and centric locations.

Comparative pharmacokinetic and pharmacodynamic characteristics of amlodipine besylate and amlodipine nicotinate in healthy subjects

BACKGROUND AND AIM

Amlodipine, a dihydropyridine calcium antagonist, is prescribed for the management of angina and hypertension, and is sold as amlodipine besylate. However, a new salt formulation, amlodipine nicotinate, has recently been developed. Here, we evaluated the comparative pharmacokinetic and pharmacodynamic characteristics of the nicotinate and besylate forms of amlodipine.

SUBJECTS AND METHODS

A randomized, 2-way crossover study was conducted in 18 healthy male volunteers to compare the pharmacokinetics and pharmacodynamics of these two forms, i.e. amlodipine nicotinate (test) and amlodipine besylate (reference), after administration of a single dose of 5 mg of each drug and a washout period between doses of 4 weeks. Blood samples for the pharmacokinetic analysis of amlodipine were obtained over the 144-hour period after administration. Systolic and diastolic blood pressures and pulse rates were recorded immediately prior to each blood sampling.

RESULTS

All participants completed both treatment periods, and no serious adverse events occurred during the study period. After administering a single dose of each formulation, mean AUC0-infinity and Cmax values were 190.91+/-60.49 ng x h/ml and 3.87+/-1.04 ng/ml for the test formulation and 203.15+/-52.05 ng x h/ml and 4.01+/-0.60 ng/ml for the reference formulation, respectively. The 90% confidence intervals of test/reference mean ratios for AUC0- infinity and Cmax fell within the predetermined equivalence range of 80 - 125%. Pharmacodynamic profiles including systolic and diastolic blood pressures and pulse rates exhibited no significant differences between the two formulations.

CONCLUSION

The two amlodipine formulations showed similar pharmacokinetic and pharmacodynamic characteristics and the new amlodipine formulation, amlodipine nicotinate, was found to be equivalent for pharmacokinetics to the currently available amlodipine besylate with respect to the rate and extent of amlodipine absorption.

Unusual renal cell carcinomas: a pictorial essay

Renal cell carcinoma (RCC) is the most common solid renal neoplasm. Clear cell (conventional) carcinoma is the most common pathologic subtype of RCC. Usually RCC is a hypervascular, solid, solitary mass with contour bulging. However, RCC can manifest different features according to the pathologic tumor subtypes. Preoperative diagnosis of cyst-associated RCC is very difficult, especially in cases of RCC originating in a cyst. Multiple or bilateral presentation of RCC occurs in fewer than 5% of cases. In addition, RCCs may demonstrate unusual findings such as infiltrative growth mimicking transitional cell carcinoma, fatty component mimicking angiomyolipoma, severe perinephric infiltration, and extensive calcifications mimicking inflammation or other tumor. RCCs can be associated with hereditary diseases such as von Hippel-Lindau disease. Familiarity with these radiologic features of unusual RCCs can help ensure correct diagnosis and proper management.

Inflammatory myofibroblastic tumor of the stomach with peritoneal dissemination in a young adult: imaging findings

Inflammatory myofibroblastic tumors are lesions that most often affect young adults and children. These tumors have been found in numerous extrapulmonary sites but rarely in the stomach. It is unknown whether this process is reactive or neoplastic. They are infiltrative lesions and often extend through the gastric wall, sometimes reaching adjacent organs including the esophagus, duodenum, peritoneal cavity, spleen. pancreas, and liver. These features mimic malignancy on endoscopy and radiology. We report the ultrasound, color Doppler ultrasound, and helical computed tomographic findings of a gastric inflammatory myofibroblastic tumor with peritoneal dissemination in a young adult. To our knowledge, this is the first report of color Doppler ultrasound and helical computed tomographic findings of this rare disease entity.

The effects of dual blockade of the renin- angiotensin system on urinary protein and transforming growth factor-b excretion in 2 groups of patients with IgA and diabetic nephropathy

AIMS

The therapeutic benefits of dual blockade of the renin-angiotensin system (RAS) have been inconsistent on renal function and proteinuria. To know the contribution of the heterogeneity of study subjects to such inconsistency, we evaluated the effects of dual blockade of RAS in 2 groups of selected renal diseases, IgA and diabetic nephropathy. To avoid confounding by the blood pressure-reducing effects, angiotensin II receptor antagonists (ATRAs) were added on the patients with long-term, optimally controlled blood pressure taking ACE inhibitors. Twenty-four-hour urinary protein excretion rate and urinary TGF-beta1 level were measured as surrogate markers of renal injury.

METHODS

We conducted a prospective crossover trial with 14 IgA and 18 type-2-diabetic nephropathy patients showing moderate degree of proteinuria (> or = 1.0 g/day) and renal dysfunction (creatinine clearance 25 - 75/ml/min). Four to 8 mg once-daily dose of candesartan and placebo were alternatively added on ramipril dose of 5 - 7.5 mg/day for 16 weeks.

RESULTS

All baseline data except for the age factor were statistically the same between the 2 disease groups. Twenty-four-hour mean arterial blood pressures were 91.2 +/- 1.6 and 92.3 +/- 1.8 mmHg in IgA and diabetic nephropathy patients respectively at baseline (p = NS). Mean arterial pressure did not change by the addition of candesartan or placebo in both groups. The addition of candesartan (combination) reduced 24-hour urinary protein excretion rate in IgA nephropathy patients with a mean change of -12.3 +/- 4.5%, which is significantly greater compared to a mean change of -0.1 +/- 3.3% after the addition of placebo (placebo) (mean difference 12.4 +/- 5.0, 95% CI 1.2 - 23.5; p < 0.05). Urinary TGF-beta1 level was reduced considerably by the combination therapy, with a -28.9 +/- 6.0% decrease, which was significantly different to that by the placebo, with +4.3 +/- 12.4% (33.3 +/- 13.5, 3.2 - 63.3; p < 0.05). In diabetic nephropathy patients, the addition of candesartan did not reduce 24-hour urinary protein excretion rate. Mean changes of 24-hour urinary protein excretion rate were -0.8 +/- 4.7% by the combination therapy and +0.5 +/- 6.1% by placebo (mean difference 1.3 +/- 4.7, 95% CI -6.8 - 13.5; p < NS). The level of urinary TGF-beta1 was reduced by the combination therapy, with -14.3 +/- 9.5% decrease, but it did not reach statistical significance compared to placebo of +0.7 +/- 15.5% (15.0 +/- 13.5, -14.4 - 44.5; p < NS). The changes in 24-hour urinary protein excretion rate and urinary TGF-beta1 level were neither correlated with each other, nor with the change in mean arterial pressure. Significant changes in the renal function were not detected during the study period.

CONCLUSION

Definite beneficial effects of dual blockade of RAS on proteinuria and TGF-beta1 excretion were found in IgA nephropathy patients, which was independent of blood pressure-reducing effect. With our 16-week trial, such benefits were not observed in type 2 diabetic nephropathy. The reduction in urinary TGF-beta1 level suggests that the combination therapy may provide additional renoprotection through the antisclerosing effects. Based on our results, for a proper interpretation the therapeutic effects of the combination therapy should be evaluated separately according to the underlying renal disease.

Identification and functional characterization of a novel mutation of hepatocyte nuclear factor-1alpha gene in a Korean family with MODY3

AIMS/HYPOTHESIS

After screening 16 Korean families with early onset Type 2 diabetes in search for hepatocyte nuclear factor (HNF) -1alpha gene mutation, we identified a novel missense mutation (R263L) associated with MODY phenotype. We studied the biological characteristics of the mutation and the potential functional consequences based on the crystallographic structure of HNF-1alpha in complex with DNA.

METHODS

DNA from subjects with a familial form of early onset diabetes was isolated and HNF-1alpha was sequenced. The R263L substitution was generated by PCR-based sited-directed mutagenesis. Functional and biochemical studies were conducted by reporter assay using glucose-transporter type 2 (GLUT2) or insulin promoters and electrophoretic mobility shift assay, respectively.

RESULTS

Transfection of wild-type HNF-1alpha increased the reporter activities of GLUT2 and insulin promoters in NIH3T3 and SK-Hep1 cells, while R263L mutant was defective in transactivation of those promoters. Both wild-type HNF-1alpha and R263L mutant could not transactivate GLUT2 and insulin promoters in MIN6N8 insulinoma cells. R263L mutant had a defective cooperation with its heterodimeric partner HNF-1beta or coactivator p300. R263L mutant protein displayed greatly reduced DNA binding ability, despite its comparable protein stability to the wild-type HNF-1alpha.

CONCLUSION/INTERPRETATION

These results suggest that the mutation of HNF-1alpha at codon 263 from arginine to leucine leads to the development of MODY3 through decreased insulin production and defective glucose sensing. These findings are in good agreement with the crystal structure in which R263 makes hydrogen bonds with phosphorus atoms of DNA backbone to mediate the stable binding of HNF-1alpha homeodomain to the promoter.

IFN gamma/TNF alpha synergism in MHC class II induction: effect of nicotinamide on MHC class II expression but not on islet-cell apoptosis

AIMS/HYPOTHESIS

Interferon-gamma (IFN gamma) and TNFalpha synergistically induce pancreatic beta-cell apoptosis. Apart from their direct effect, we studied the possible indirect immunological role of IFNgamma/TNFalpha synergism on pancreatic beta-cell death by investigating MHC class II induction by cytokines. The effect of nicotinamide on the cytokine-induced MHC class II expression and pancreatic beta-cell death was also studied.

METHODS

Immunocytochemistry, flow cytometry and RNase protection assay were used to study MHC class II expression. Immunoblotting was done to study downstream signals of IFN gamma. The effects of nicotinamide on islet-cell apoptosis and diabetes mellitus were examined using MTT assay and adoptive transfer model.

RESULTS

IFN gamma alone induced MHC class II expression on a small number of insulinoma cells. TNFalpha alone did not induce MHC class II expression, but enhanced IFN gamma-induced MHC class II expression. MHC class II expression by cytokine(s) was due to the induction of class II transactivator (CIITA). Nicotinamide reduced MHC class II expression by cytokine(s) but did not protect insulinoma-cell apoptosis by IFN gamma and TNFalpha in combination or protect against the development of diabetes mellitus after adoptive transfer of diabetogenic lymphocytes.

CONCLUSION/INTERPRETATION

IFN gamma and TNFalpha synergistically induced MHC class II expression on insulinoma cells through the induction of CIITA; nicotinamide reduced the expression of cytokine-induced MHC class II expression on insulinoma cells through its effect on CIITA expression; and the preventive effect of nicotimamide on Type I (insulin-dependent) diabetes mellitus is probably due to its effect of MHC class II expression rather than that on islet cell apoptosis.

Malignant mixed müllerian tumor of the ovary: imaging findings

OBJECTIVE

We describe the imaging findings of malignant mixed müllerian tumor (MMMT) of the ovary, which have not previously been reported.

MATERIALS AND METHODS

We experienced 13 cases of ovarian MMMT in eight patients. All patients underwent surgical resection and the MMMTs were confirmed pathologically. US (n = 8), CT (n = 8), and MRI (n = 1) examinations were performed before operation. Imaging features were analyzed retrospectively for bilaterality, tumor solidity (cystic or solid), size, and contrast enhancement of the tumor on CT and MRI. Presence of ascites and other evidence of peritoneal seeding, adjacent organ invasion, distant metastasis, and surgical staging were also evaluated.

RESULTS

There were bilateral ovarian MMMTs in five patients and unilateral MMMTs in three patients. Two of the MMMTs were multiseptated cystic, and 11 were mixed (solid and cystic). The diameter of the largest dimension was less than 5 cm in one case, 5-10 cm in two cases, and larger than 10 cm in 10 cases. Dense homogeneous contrast enhancement of the solid component was seen in 11 mixed masses. Ascites were found in all patients. Other evidence of peritoneal seeding and direct invasion into adjacent organ such as the uterus or sigmoid colon was seen in five patients each. Pleural metastasis was present in one patient. Surgical stages were FIGO classification IIIb and IV in one patient each, and IIIc in six patients.

CONCLUSION

Ovarian MMMTs usually present as aggressive, bilateral, large, solid and cystic tumors, combined with ascites, frequent peritoneal seeding, and adjacent organ invasion.

A transplantable sorting signal that is sufficient to mediate rapid recycling of G protein-coupled receptors

The beta(2)-adrenergic receptor and delta opioid receptor represent distinct G protein-coupled receptors that undergo agonist-induced endocytosis via clathrin-coated pits but differ significantly in their postendocytic sorting between recycling and degradative membrane pathways, respectively. Previous results indicate that a distal portion of the carboxyl-terminal cytoplasmic domain of the beta(2)-adrenergic receptor, which engages in PDZ domain-mediated protein interaction, is required for efficient recycling of receptors after agonist-induced endocytosis. Here we demonstrate that a four-residue sequence (DSLL) comprising the core of this protein interaction domain functions as a transplantable endocytic sorting signal that is sufficient to re-route endocytosed delta opioid receptor into a rapid recycling pathway, to inhibit proteolytic down-regulation of receptors, and to mediate receptor-autonomous sorting of mutant receptors from the wild type allele when co-expressed in the same cells. These observations define a transplantable signal mediating rapid recycling of a heterologous G protein-coupled receptor, and they suggest that rapid recycling of certain membrane proteins does not occur by bulk membrane flow but is instead mediated by a specific endocytic sorting mechanism.

Injuries from falls in the pediatric population: an analysis of 729 cases

BACKGROUND/PURPOSE

Falls are classified as low or high level for triage purposes. Because triage criteria dictate less urgency for low-level falls, this classification scheme has important implications for pediatric emergency care.

METHODS

Retrospective analysis was conducted of 729 (393 low-level and 336 high-level) pediatric patients treated for fall-related trauma (1992 through 1998). Falls were classified as low (<15 feet) or high-level (> or =15 feet). All falls were reported as accidental or unintentional.

RESULTS

The overall mortality rate was 1.6% (2.4% for high-level falls compared with 1.0% for low-level falls). All 4 patients who died of a low-level fall had an abnormal head computed tomography (CT) scan and intracranial hypertension. Half of deaths from high-level falls were attributable to intracranial injuries, and half were caused by severe extracranial injuries. Common extracranial injuries were upper extremity fracture (6.2%), lower extremity fracture (5.6%), pulmonary contusion (1.8%), pneumothorax (1.1%), liver laceration (1.1%), bowel injury (1.0%), and splenic injury (2.1%). Orthopedic and thoracic injuries resulted more commonly from high-level falls, whereas abdominal injuries were as likely to occur after a low-level fall.

CONCLUSIONS

Intracranial injury accounts for the majority of deaths from falls. Children suffering low-level falls were at similar risk for intracranial and abdominal injuries compared with those who fell from greater heights. Pediatric trauma triage criteria should account for these findings.

Gene profile of replicative senescence is different from progeria or elderly donor

In vitro cellular senescence of human diploid fibroblast has been a good model for aging research, which shows similar phenotypes to in vivo aging. Gene expression profiling would provide an insight to understand the mechanism of senescence. Using cDNA microarray containing 384 known genes, we compared the expression profiles of three different types of aging models: replicative senescence, fibroblasts from progeria or from elderly donor. Although all of them showed senescence phenotypes, distinct sets of genes were altered in each group. Pairwise plots or cluster analysis of activation fold of gene expression revealed closer relationships between fibroblasts from progeria or from old individual, but not between replicative senescence fibroblasts and either models. Differential expression pattern of several genes were confirmed by RT-PCR. We suggest that the replicative senescence model might behave differently to other types of aging models due to the distinct gene expression.

IFN-gamma/TNF-alpha synergism as the final effector in autoimmune diabetes: a key role for STAT1/IFN regulatory factor-1 pathway in pancreatic beta cell death

Fas ligand (FasL), perforin, TNF-alpha, IL-1, and NO have been considered as effector molecule(s) leading to beta cell death in autoimmune diabetes. However, the real culprit(s) in beta cell destruction have long been elusive, despite intense investigation. We and others have demonstrated that FasL is not a major effector molecule in autoimmune diabetes, and previous inability to transfer diabetes to Fas-deficient nonobese diabetic (NOD)-lpr mice was due to constitutive FasL expression on lymphocytes from these mice. Here, we identified IFN-gamma/TNF-alpha synergism as the final effector molecules in autoimmune diabetes of NOD mice. A combination of IFN-gamma and TNF-alpha, but neither cytokine alone, induced classical caspase-dependent apoptosis in insulinoma and pancreatic islet cells. IFN-gamma treatment conferred susceptibility to TNF-alpha-induced apoptosis on otherwise resistant insulinoma cells by STAT1 activation followed by IFN regulatory factor (IRF)-1 induction. IRF-1 played a central role in IFN-gamma/TNF-alpha-induced cytotoxicity because inhibition of IRF-1 induction by antisense oligonucleotides blocked IFN-gamma/TNF-alpha-induced cytotoxicity, and transfection of IRF-1 rendered insulinoma cells susceptible to TNF-alpha-induced cytotoxicity. STAT1 and IRF-1 were expressed in pancreatic islets of diabetic NOD mice and colocalized with apoptotic cells. Moreover, anti-TNF-alpha Ab inhibited the development of diabetes after adoptive transfer. Taken together, our results indicate that IFN-gamma/TNF-alpha synergism is responsible for autoimmune diabetes in vivo as well as beta cell apoptosis in vitro and suggest a novel signal transduction in IFN-gamma/TNF-alpha synergism that may have relevance in other autoimmune diseases and synergistic anti-tumor effects of the two cytokines.

Comparison of anxiety assessments between clinicians and patients with acute myocardial infarction in cardiac critical care units

BACKGROUND

Although anxiety is common after acute myocardial infarction and can adversely affect physical recovery, it is not part of the routine clinical assessment of patients with myocardial infarction. Furthermore, evidence suggests that patients and clinicians differ significantly in their assessments of patients' anxiety levels.

OBJECTIVES

To determine the extent to which clinicians assess anxiety in patients with acute myocardial infarction and to compare patients' self-ratings with their clinicians' assessments.

METHODS

In a prospective, descriptive study, 101 patients used the Spielberger State Anxiety Index to assess their anxiety during the first 48 hours after admission for acute myocardial infarction. Patients' scores were compared with nurses' and physicians' assessments of the patients' anxiety as reported in the medical record.

RESULTS

Only 45 patients (45%) had anxiety assessments noted in the record. Of those 45, 26 patients (58%) were described simply as anxious without any further description of the level of anxiety. Eleven (24%) of those 45 patients had behaviors of anxiety recorded, again without any indication of the level of anxiety. No association between patients' self-assessments and their clinicians' assessments was apparent (lambda = .03; P > .05).

CONCLUSIONS

Anxiety was not routinely assessed, despite nearly half the patients reporting moderate to extreme anxiety when asked. When clinicians assessed anxiety, their assessments did not match patients' self-ratings of anxiety. A simple, easy-to-use instrument for discriminating levels of anxiety is needed.

Comparison of anxiety assessments between clinicians and patients with acute myocardial infarction in cardiac critical care units

BACKGROUND: Although anxiety is common after acute myocardial infarction and can adversely affect physical recovery, it is not part of the routine clinical assessment of patients with myocardial infarction. Furthermore, evidence suggests that patients and clinicians differ significantly in their assessments of patients' anxiety levels. OBJECTIVES: To determine the extent to which clinicians assess anxiety in patients with acute myocardial infarction and to compare patients' self-ratings with their clinicians' assessments. METHODS: In a prospective, descriptive study, 101 patients used the Spielberger State Anxiety Index to assess their anxiety during the first 48 hours after admission for acute myocardial infarction. Patients' scores were compared with nurses' and physicians' assessments of the patients' anxiety as reported in the medical record. RESULTS: Only 45 patients (45%) had anxiety assessments noted in the record. Of those 45, 26 patients (58%) were described simply as anxious without any further description of the level of anxiety. Eleven (24%) of those 45 patients had behaviors of anxiety recorded, again without any indication of the level of anxiety. No association between patients' self-assessments and their clinicians' assessments was apparent (lambda = .03; P &gt; .05). CONCLUSIONS: Anxiety was not routinely assessed, despite nearly half the patients reporting moderate to extreme anxiety when asked. When clinicians assessed anxiety, their assessments did not match patients' self-ratings of anxiety. A simple, easy-to-use instrument for discriminating levels of anxiety is needed.

Intestinal metastases from gastric adenocarcinoma: helical CT findings

PURPOSE

The purpose of this work was to describe the helical CT findings of intestinal metastasis from gastric adenocarcinoma.

METHOD

Twenty-three patients with intestinal metastasis from gastric adenocarcinoma found at helical CT were included. CT findings and clinical and pathologic data were reviewed.

RESULTS

The most common characteristic finding was target-like concentric bowel wall thickening (thick inner high-outer low, n = 18) involving multiple long segments with progressive thickening of the enhancing inner layer. Fifteen cases (65%) involved multiple sites, and the ascending colon (n = 12) and rectum (n = 11) were the two most common sites. Peritoneal carcinomatosis (n = 15, 65%) and bowel obstruction (n = 14, 61%) were common associated findings. Regarding the primary lesion, the majority was linitis plastica (n = 16) and poorly differentiated adenocarcinoma with or without signet-ring cell differentiation (n = 14).

CONCLUSION

Intestinal metastasis from gastric adenocarcinoma, especially of the linitis plastica type, most commonly showed target-like long segmental wall thickening with a characteristically thick inner enhancing layer on helical CT.

Mechanism of refractory ceramic fiber- and rock wool-induced cytotoxicity in alveolar macrophages

OBJECTIVES

Man-made vitreous fibers (MMVFs) can induce cytotoxicity in a way similar to that of other particles, including silica and asbestos fibers. However, as yet the mechanism of MMVF-induced cytotoxicity is still not clear. This report aims to clarify the mechanism of MMVF-induced cytotoxicity in the alveolar macrophage (AM). In this mechanism, an attempt to prove the involvement of the adenosine triphosphate (ATP) generation system and the polyinosinic acid-inhibitable scavenger receptors was made.

METHODS

Several parameters were observed for cytotoxicity, such as cell viability, the release of lactic dehydrogenase (LDH) and ATP levels in rat AM's that were treated with refractory ceramic fibers (RF2) and rock wool (RW1). A specially designed ATP generation system was used to determine the effect of MMVF on ATP generation. A scavenger receptor ligand was applied to evaluate the relationship between scavenger receptors and MMVF-induced ATP depletion.

RESULTS

A 3-(4,5-dimethylthiazol)-2,5-diphenyl tetrazolium bromide (MTT) assay indicated that both RF2 and RW1 caused a decrease in cell viability and this decrease was concentration-dependent. RF2 and RW1 increased the release of LDH with increasing fiber concentration. From these parameters, RF2 was shown to exhibit greater cytotoxicity than did RW1. Both fibers decreased the intracellular ATP content and this decrease was concentration-dependent. The decrease was more pronounced in RW1 than in RF2 at all fiber concentrations. These fibers suppressed succinate-triggered oxygen consumption. Polyinosinic acid, a ligand of the scavenger receptor, inhibited the MMVF-induced decrease in ATP concentration.

CONCLUSION

These results suggest that RF2 and RW1 can induce cytotoxicity and ATP depletion in the AM through the polyinosinic acid-inhibitable scavenger receptor. ATP depletion was the important factor in MMVF cytotoxicity, especially by RW1.

Efficient intracellular delivery of GFP by homeodomains of Drosophila Fushi-tarazu and Engrailed proteins

The 60 amino acid long homeodomain of Antennapedia (Antp), either alone or as a fusion protein with 30-40 amino acid long foreign polypeptides, has been reported to cross biological membranes by an energy- and receptor-protein-independent mechanism. Moreover, the 16 amino acid long third helix of the Antp homeodomain, so-called penetratin, possesses translocation properties when fused to fewer than 100 amino acids as well. These findings led us to study whether such a protein tansduction property is shared by other homeodomains. We report here that homeodomains of two homeoproteins, Fushi-tarazu and Engrailed, are able to transduce a 238 amino acid long green fluorescent protein into cultured cells as efficiently as other well-known protein transduction domains, such as an internal oligopeptide of Tat and penetratin. These findings suggest that such transduction activity of homeodomains might have some physiological roles and that it can be exploited for development of efficient transduction vectors for research use and protein therapy.

Recent advances in particulate-induced pulmonary fibrosis; for the application of possible strategy experimentally and clinically

Chronic interstitial lung diseases including pneumoconiosis have pathological characteristics which alter the lung structure and function consequent to the accumulation and activation of inflammatory cells in the lower respiratory tract. These activated cells usually secrete the inflammatory and fibrogenic mediators. Of the diffuse parenchymal lung diseases, the majority have no known etiology and idiopathic pulmonary fibrosis (IPF) is the diagnosis most frequently encountered by clinicians. Pathogenic similarities between pneumoconiosis and IPF provide a strong basis for hypothesizing that environmental agents may cause IPF. Many case-control studies have been published that provide further evidence for a number of associations between occupational and environmental exposures and IPF. Such reports support a strong evidence that IPF may be a heterogenous disorder associated with a number of environmental exposures. As a model of lung fibrosis, experimental pneumoconiosis is giving us a great information because crystalline silica is probably one of the most typical agent producing pulmonary fibrosis and the severity of its health effects and the widespread nature of exposure have been long recognized. Many papers provide evidence that particles have the potential to cause stimulation of phagocytes to release oxidants and such oxidative stress is believed to be a major factor in pulmonary inflammation followed by fibrotic change. Many kinds of cellular mediators are recognized as a implicating factor in this process including cell-to-cell interaction, enzymes, cytokines, arachidonic acid derivatives et al. Treatment of pneumoconiosis is an attractive and interesting topic. But, the mechanism of pathogenesis of pneumoconiosis is not thoroughly understood yet. Also, whether the process of fibrosis formation be retarded or not is questionable with some therapeutic trial. Therefore, a sensitive biomarker which is possible to estimate the pathological pathway in pneumoconiosis is needed. Our laboratory has studied particulate-induced pulmonary reaction for two decades consistently. This review will focus on signal transduction pathway involved in oxidative stress and some inhibitory agents with pleiotropic mechanism in pulmonary fibrosis. I will also introduce some data of animal studies with multidrug regimen as well.

Identity of mouse IA-2 and PTP35 genes of the tyrosine phosphatase family, and their expression in neuroendocrine tissues

Recently, IA-2, one of the major diabetic autoantigens, and PTP35 cDNA were independently isolated by subtraction cloning using insulinoma cells and a polymerase chain reaction (PCR)-based search for conserved sequences using NIH3T3 fibroblast cell line, respectively. By Southern blot analysis and nucleotide sequence determination of reverse transcription PCR products, we showed that IA-2 and PTP35 are identical and exist as a single gene in a mouse genome. The expression of IA-2/PTP35 messages was detected by northern blot analysis in MIN6N8 cells, an insulinoma cell line derived from non-obese diabetic mice, but its expression level was not affected by the ambient glucose level, phorbol-12-myristate 13-acetate or tumour necrosis factor-alpha. We also generated polyclonal antibodies to murine IA-2/PTP35 by immunization with recombinant proteins. Subsequent immunohistochemical analysis using these polyclonal antibodies disclosed that IA-2/PTP35 is strongly expressed in mouse neuroendocrine tissues such as pancreatic islets and the hypothalamus-pituitary gland. These results suggest that IA-2/PTP35 functions primarily in neuroendocrine tissues.

Identification and partial characterization of a novel hemolysin from Leptospira interrogans serovar lai

It has been suggested that leptospiral hemolysins are important in the virulence and pathogenesis of leptospirosis. We have isolated an Escherichia coli clone carrying the 7.8kb DNA insert from a genomic library of Leptospira interrogans serovar lai by plaque hybridization using a sequence derived from the sphingomyelinase C gene (sphA) of L. borgpetersenii. The clone showed a clear beta-hemolytic zone on sheep blood agar and high hemolytic activities on both human and sheep erythrocytes in liquid assays. The clone carried at least two genes responsible for the hemolytic activities, encoded by two open reading frames of 1662 and 816 nucleotides, which are named sphH and hap-1 (hemolysis associated protein-1), respectively. The SphH showed 75% homology to the SphA at the amino acid level, and the Hap-1 showed no significant homology in major databases. Interestingly, however, E. coli cells harboring sphH did not show sphingomyelinase or phospholipase activities. Moreover, SphH-mediated hemolysis was osmotically protected by polyethylene glycol 5000, suggesting that the hemolysis is likely to be caused by pore formation on the membrane. The SphH was successfully expressed in E. coli as a histidine (His)-SphH fusion protein. Both sphH and hap-1 were highly conserved among the Leptospira species, except for the absence of sphH in non-pathogenic L. biflexa serovar patoc. We concluded that the SphH is a novel hemolysin of a pathogenic Leptospira species, which may be a putative pore-forming protein.

The endonuclease activity of the yeast Dna2 enzyme is essential in vivo

Dna2 is a multifunctional enzyme in yeast that possesses endonuclease activity well suited to remove RNA-DNA primers of Okazaki fragments, raising the question of whether endonuclease activity is essential for in vivo Dna2 function. Systematic site-directed mutations of amino acid residues in Saccharomyces cerevisiae DNA2 conserved in the central region of many eukaryotic DNA2 homologs allowed us to identify mutant dna2 alleles that were divided into three groups based on the viability of the mutant cells: (i) viable; (ii) inviable only when expression was repressed; (iii) inviable. Biochemical analyses of recombinant mutant Dna2 proteins isolated from the latter two groups revealed that they possessed normal ATPase/helicase activity, but were impaired in their endonuclease activity. Cells expressing mutant Dna2 enzymes partially impaired in endonuclease activity were viable, but were unable to grow when expression of their mutant Dna2 enzymes was further reduced. Their growth was restored when the mutant Dna2 proteins decreased in nuclease activity were induced to overexpress. In contrast, mutant Dna2 proteins lacking endonuclease activity did not allow cells to grow under any conditions tested. These in vivo and in vitro results demonstrate that the endonuclease activity of Dna2 is essential for Okazaki fragment processing.

Differences between men and women in anxiety early after acute myocardial infarction

BACKGROUND: Anxiety after acute myocardial infarction influences both short- and long-term recovery. Therefore, determining specific subgroups of patients who have relatively higher anxiety levels is important. Published findings about gender differences in anxiety after acute myocardial infarction are conflicting. OBJECTIVES: To determine whether gender differences in anxiety after acute myocardial infarction exist and whether any of the sociodemographic and clinical variables that often differ between men and women with acute myocardial infarction interact with gender to influence anxiety. METHODS: A total of 424 patients with confirmed acute myocardial infarction were enrolled in this multicenter prospective study. Patients' anxiety level was measured within 72 hours of their arrival at the hospital by using the State Anxiety Inventory and the Brief Symptom Inventory. RESULTS: Women had significantly higher anxiety than did men according to both the State Anxiety Inventory (42 +/- 12.9 vs 37.7 +/- 12.5; P = .001) and the Brief Symptom Inventory (0.83 +/- 0.97 vs 0.63 +/- 0.71; P = .02). Of the sociodemographic and clinical variables examined, only marital status and income significantly interacted with gender to influence anxiety. Married women had higher anxiety than did single and widowed women, and married men had lower anxiety than did single men. Women with lower income had higher anxiety than did women with higher income; income was not related to anxiety in men. CONCLUSION: Women report significantly greater anxiety early after acute myocardial infarction than men do. Women's greater anxiety may be partially explained by marital status and lower income at the time of the infarction.