Pericardial diverticulum arising from the right lateral superior aortic recess: a mimicker of cystic anterior mediastinal mass

AIM

To report the prevalence of pericardial diverticulum of the right lateral superior aortic recess (RSAR) on computed tomography (CT), to analyse the structural CT findings of whether or not the structure is large enough to be seen on chest radiographs, and to describe changes in size and shape of RSAR on follow-up CT.

MATERIALS AND METHODS

A well-circumscribed, fluid-attenuation lesion in the anterior mediastinum with the following CT features was defined as a pericardial diverticulum of the RSAR: no enhancing wall, communication with the RSAR, abutment to the heart with an acute angle, and moulding by adjacent structures. Chest CT images of 31 patients with the diverticulum were evaluated, including four selected from 1,130 consecutive patients (0.4%).

RESULTS

The diverticulum projected ventrally from the RSAR and its largest size on axial CT ranged between 12-56 mm. Although the RSAR and the largest diverticular portion were usually seen on the same axial image (n=19), the latter sometimes lay above (n=1) or below (n=11) the former. On sagittal images, the last 11 diverticula resembled teardrops hanging from the RSAR by small stems. All of the 24 patients, each with 1-31 follow-up CT examinations, showed size fluctuations ranging between 1-46 mm (mean, 16 mm) during a follow-up period of 0.5-172 months (mean, 65 months). The diverticulum was not identifiable in five cases and was identifiable but did not show a connection with the RSAR in three cases when the diverticulum was smallest in size.

CONCLUSIONS

In cases of cystic anterior mediastinal mass, a deliberate search for its connection with the RSAR on all available CT images including previous studies is necessary for the diagnosis of pericardial diverticulum of the RSAR.

Nuclear endonuclease G controls cell proliferation in ovarian cancer

Ovarian cancer is characterized by a high degree of genetic heterogeneity. Platinum-based chemotherapy and some gene-targeted therapies have shown limited treatment efficacy due to toxicity and recurrence, and thus, it is essential to identify additional therapeutic targets based on an understanding of the pathological mechanism. Here, we report that endonuclease G, which exhibits altered expression in ovarian cancer, does not function as a cell death effector that digests chromosomal DNA in ovarian cancer. Endonuclease G is modulated by intracellular reactive oxygen species dynamics and plays a role in cell proliferation in ovarian cancer, suggesting that targeting endonuclease G alone or in combination with other antitumor agents may have the potential for development into a treatment for endonuclease G-overexpressing cancers, including ovarian cancer.

Prenatal diagnosis of vascular ring: evaluation of fetal diagnosis and postnatal outcomes

Funding Acknowledgements

Type of funding sources: None.

Background

The performance of fetal echocardiogram in diagnosing vascular ring (VR) and its impact on postnatal outcomes has not been well examined.

Methods

We reviewed all patients with VR diagnosis from 2000-2020.

Results

50 patients with antenatal diagnosis of VR; 42(84%) with right aortic arch aberrant left subclavian artery and left-sided ductus arteriosus ((RAA-ALS) and 8(16%) with double aortic arch (DAA) were compared to 120 patients with postnatal diagnosis; 90(75%) with DAA, 22(18%) with RAA-ALS (Table 1). Prenatal diagnosis of VR increased over study period; 4 vs 31, 10 vs 29, 14 vs 25, 22 vs 35 between 2000-2005, 2005-2010, 2010-2015, and 2015-2020 respectively, p< 0.01. Prenatal diagnosis of VR was associated with less symptoms [26(52%) vs 72(60%), p < 0.003] and less cross-sectional imaging [22(44%) vs 82(69%), p = 0.0001]. Postnatal diagnosis of VR was associated with more surgical interventions (102(85%) vs 28(56%), p = 0.002), later surgical repair (22.9 ± 35 vs 12.6 ± 10.2 months, p < 0.01), more postoperative complications [8/102 (7.8%) vs 1/28 (3.5%), p = 0.04] and more residual symptoms (2/28(7%) vs 30/102(29%), p = 0.001 respectively].

Conclusion

Prenatal diagnosis of VR has evolved over time. RAA-ALS versus DAA were dominant in the prenatally and postnatally diagnosed cohorts respectively. Prenatal diagnosis of VR was associated less symptoms, less cross-sectional imaging, earlier age of surgical intervention and less residual symptoms.

Table 1 Prenatal Diagnosis (N = 50) Postnatal Diagnosis (N = 120) p-value Gestational Age (weeks) 39 ± 3 38 ± 2 0.9 Male (%) 31 (62%) 69(58%) 0.8 Subtype of vascular ring: Double aortic arch RAA-ALSA Others 8 (16%) 42 (80 %) 0 (0 %) 90 (72%) 22 (17%) 8 (11%) 0.002 0.01 Associated intracardiac CHD: VSD TOF DORV AVSD Coarctation of aorta Others 11 (22%) 1 1 3 0 3 3 24 (20%) 5 7 2 2 3 5 0.8 Associated genetic diagnosis: 22q11 deletion Trisomy 21 Others 9 (18%) 6 3 0 32 (26%) 29 3 0 0.1 Symptomatic presentation: Respiratory Gastrointestinal 26 (52 %) 15 11 72 (60 %) 57 15 <0.03 Age at first symptoms (month) 3.2 ± 2.8 21.6 ± 37 0.01 Diagnostic modalities: Fetal echocardiogram Postnatal echocardiogram Barium swallow Bronchoscopy CT scan MRI 50 (100%) 50 (100%) 2 (4%) 3 (6%) 18 (36 %) 4 (8%) 0 (0%) 120 (100%) 23 (25 %) 18 (15 %) 65 (54%) 7 (14%) Surgical repair 28 (56%) 102 (85%) 0.02 Age at surgical repair (month) 12.6 ± 10.2 22.9 ± 35 <0.01 Postoperative complications 1 (3%) 8 (7%) 0.03 Residual symptoms 2 (1%) 30 (25%) 0.001 Age at most recent follow up (mo) 26 ± 7 60 ± 7 0.02 Table 1: Comparison of patients with prenatal versus postnatal diagnosis of vascular ring

Effects of Inflammatory Disease on Clinical Progression and Treatment of Ischiogluteal Bursitis: A Retrospective Observational Study

Introduction:

The symptoms of Ischiogluteal Bursitis (IGB) are often nonspecific and atypical, and its diagnosis is more challenging. Moreover, it is difficult to predict cases of chronic progression or poor treatment response. Therefore, the aim of this study was to investigate the clinical course of IGB patients and identify factors that are predictive of failure of conservative treatment.

Materials and Methods:

Our study consisted of IGB patients diagnosed between 2010 March and 2016 December who had been followed-up for at least one year. Structured questionnaires and medical records were reviewed to analyse demographic characteristics, lifestyle patterns, blood tests, and imaging studies. We categorized the cases into two groups based on the response to conservative treatment and the need for surgical intervention.

Results:

The most common initial chief symptoms were buttock pains in 24 patients (37.5%). Physical examinations showed the tenderness of ischial tuberosity area in 59 (92.2%) patients, but no specific findings were confirmed in 5 patients (7.8%). 51 patients (79.7%) responded well to the conservative management, 11 patients (17.2%) needed injection, and 2 patients (3.1%) had surgical treatment performed due to continuous recurrence. There was no difference in demographic and blood lab data between the two groups. However, the incidence of inflammatory diseases (response group: 10.3% vs non-response group: 66.7%, p=0.004) was significantly different between the two groups.

Conclusion:

The diagnosis of IGB can be missed due to variations in clinical symptoms, and cautions should be exercised in patients with inflammatory diseases as conservative treatment is less effective in them, leading to chronic progression of IGB.

Stabilization of C-terminal binding protein 2 by cellular inhibitor of apoptosis protein 1 via BIR domains without E3 ligase activity

C-terminal binding protein 2 (CtBP2) is a transcriptional co-repressor that regulates many genes involved in normal cellular events. Because CtBP2 overexpression has been implicated in various human cancers, its protein levels must be precisely regulated. Previously, we reported that CtBP1 and CtBP1-mediated transcriptional repression are regulated by X-linked inhibitor of apoptosis protein (XIAP). In the present study, we sought to investigate whether CtBP2 is also regulated by XIAP or any other human IAP. We found that cIAP1 interacts with CtBP2 via through BIR domains to regulates the steady-state levels of CtBP2 protein in the nucleus. The levels of CtBP2 were gradually increased upon cIAP1 overexpression and downregulated upon cIAP1 depletion. Interestingly, the RING domain of cIAP1 responsible for E3 ligase activity was not required for this regulation. Finally, the levels of CtBP2 modulated by cIAP1 affected the transcription of CtBP2 target genes and subsequent cell migration. Taken together, our data demonstrate a novel function of cIAP1 which involves protecting CtBP2 from degradation to stabilize its steady-state level. These results suggest that cIAP1 might be a useful target in strategies aiming to downregulate the steady-state level of CtBP2 protein in treating human cancers.

P1488 Anomalous origin of left coronary artery from right pulmonary artery in association with scimitar syndrome

Clinical Presentation

A full-term neonate was referred to our institution because of respiratory distress. CXR was significant for right lung hypoplasia and mild cardiomegaly. ECG showed normal sinus rhythm, right atrial enlargement, and right ventricular hypertrophy with no signs of ischemia.

Imaging Findings

The initial echocardiogram demonstrated PAPVD with the right upper pulmonary vein draining into IVC/RA junction with flow acceleration (mean gradient= 7 mmHg), moderate ASD, small muscular VSD with left-right shunting, moderate PDA with bidirectional shunting. Forward flow was seen in the proximal part of left main coronary artery (LMCA). RV systolic pressure was supra-systemic with a qualitatively moderately reduced RV systolic function.

The patient was taken to the catheterization lab where MPA angiography revealed an antegrade flow from the RPA into LMCA supplying both the anterior descending and the circumflex arteries. A selective injection within the scimitar vein showed drainage of the right lung into a vertical vein connecting with stenosis to IVC.

A follow up echocardiogram to re-examine the coronary origin revealed an anomalous origin of LMCA from proximal RPA; 3 mm distal to branch pulmonary artery bifurcation with mainly antegrade low velocity flow into LMCA and LAD. (Image 1)

Role of Imaging in Patient Care

- Imaging of the coronary origin in patients with ALCAPA can be challenging especially if the LMCA originates from RPA. Also, the presence of pulmonary hypertension might contribute to maintain coronary perfusion and lead to misinterpretation of the antegrade flow in LMCA and its branches.

- In certain situations, cardiac catheterization is essential to make the diagnosis of ALCAPA which prevented a potentially catastrophic outcome. Catheter intervention with a series of balloon dilations of the stenotic scimitar vein was successful in relieving the stenosis.

Summary/Discussion Points:

- Extensive review of the available literature revealed only three cases of Scimitar syndrome associated with ALCAPA. In all of these cases, the LMCA originated from the posterior sinus of MPA. Our case is the first to report ALCAPA from RPA in association with Scimitar syndrome. This presentation might have led to the initial misinterpretation of the echocardiography images.

- The presence of pulmonary hypertension in our patient maintained an adequate antegrade flow across the LMCA preventing significant coronary steal and signs of myocardial ischemia.

- The report highlights the challenges in making the diagnosis of ALCAPA with echocardiograms. Moreover, we discuss the role of cross-sectional and invasive imaging to rule out potential coronary arteries anomalies in patients with Scimitar syndrome, as this a rare although a very significant association that may have important implications in their outcomes.

Abstract P1488 Figure. ALCAPA origin from RPA

Ubiquitin-proteasome dependent regulation of Profilin2 (Pfn2) by a cellular inhibitor of apoptotic protein 1 (cIAP1)

The two major isoforms of the profilin (Pfn) family of proteins in mammals are Pfn1 and Pfn2. Pfn1 is a universal actin cytoskeletal regulator, while Pfn2 is an actin binding protein and mediator of synapse architecture, specific to neural tissues. However, it has recently been suggested that Pfn2 is also widely distributed in various tissues and involved in numerous cellular events as well as cytoskeletal regulation. In our previous study, we showed that Pfn1 is regulated by carboxyl terminus of Hsc70-Interacting Protein (CHIP) via an ubiquitin (Ub) proteasome system; although, the mechanism of regulation of Pfn2 is unknown. In this report, we demonstrate that Pfn2 is heavily ubiquitinated via differential Ub-linkages for degradation or as a regulatory signal. We also show that cellular inhibitor of apoptosis 1 (cIAP1) rather than CHIP, functions as an E3 ligase that targets Pfn2 for proteasomal degradation. Finally, we observed that Pfn2 levels, regulated by cIAP1, affected intracellular levels of reactive oxygen species. These results may provide a regulatory mechanism for cellular function of Pfn2 in various tissues.

Genetic evolution of classical swine fever virus under immune environments conditioned by genotype 1-based modified live virus vaccine

Modified live vaccines (MLVs) based on genotype 1 strains, particularly C-strain, have been used to prevent and control classical swine fever virus (CSFV) worldwide. Nevertheless, a shift in the predominant CSFV strains circulating in the field from genotype 1 or 3 to genotype 2 is seen. Genotype 2 is genetically distant from the vaccine strains and was recently reported during outbreaks after vaccine failure; this has raised concerns that vaccination has influenced viral evolution. In Korea in 2016, there was an unexpected CSF outbreak in a MLV-vaccinated commercial pig herd. The causative CSFV strain was genetically distinct from previously isolated Korean strains but similar to recent Chinese strains exhibiting enhanced capacity to escape neutralization; this suggests the need for global cooperative research on the evolution of CSFV. We analysed global E2 sequences, using bioinformatics tools, revealing the evolutionary pathways of CSFV. Classical swine fever virus genotypes 1 and 2 experienced different degrees and patterns of evolutionary growth. Whereas genotype 1 stayed relatively conserved over time, the genetic diversity of genotype 2 has progressively expanded, with few fluctuations. It was determined that genotype 2 evolved under lower immune pressures and at a higher evolutionary rate than genotype 1. Further, several selected codons, under diversifying selection in genotype 1 but under purifying selection in genotype 2, correspond to antigenic determinants, which could lead to evasion of vaccine-induced immunity. Our findings provide evidence that evolutionary changes in CSFV are the result of the disproportionate usage of the CSF MLVs in endemic areas; this underscores the need to develop mitigation strategies to minimize the substantial risk associated with the emergence of vaccine-escaping mutants.

A novel function of cIAP1 as a mediator of CHIP-driven eIF4E regulation

eIF4E is an initiator protein in cap-dependent translation. Its overexpression is linked to tumorigenesis in various human cancers, suggesting that the levels of eIF4E must be under tight control in normal cells. Although several eIF4E regulatory mechanisms have been demonstrated, the intracellular mechanisms controlling eIF4E protein levels remain poorly understood. Here, we report that eIF4E is efficiently regulated by dual mechanisms, both involving human inhibitor of apoptosis family protein cIAP1. cIAP1 itself ubiquitinates eIF4E as an E3 ligase, and interestingly, cIAP1 also functions as a mediator to present eIF4E to another E3 ligase, CHIP. This collaborative activity of cIAP1 and CHIP directs eIF4E toward degradation, controlling its levels and suppressing tumorigenesis. Our results provide the first evidence for a mediator function of cIAP1 and collaborative activity of cIAP1 and CHIP, suggesting that maintaining balanced levels of these E3 ligases might be beneficial for normal cell growth.

Hematological adverse effects and pharmacokinetics of ribavirin in pigs following intramuscular administration

Ribavirin (RBV) is a synthetic guanosine analog that is used as a drug against various viral diseases in humans. The in vitro antiviral effects of ribavirin against porcine viruses were demonstrated in several studies. The purposes of this study were to evaluate the adverse effects and pharmacokinetics of ribavirin following its intramuscular (IM) injection in pigs. Ribavirin was formulated as a double-oil emulsion (RBV-DOE) and gel (RBV-Gel), which were injected into the pigs as single-dose IM injections. After injection of RBV, all of the pigs were monitored. The collected serum and whole blood samples were analyzed by liquid chromatography-tandem mass spectrometry and complete blood count analysis, respectively. All of the ribavirin-treated pigs showed significant decreases in body weight compared to the control groups. Severe clinical signs including dyspnea, anorexia, weakness, and depression were present in ribavirin-treated pigs until 5 days postinjection (dpi). The ribavirin-treated groups showed significant decrease in the number of red blood cells and hemoglobin concentration until 8 dpi. The mean half-life of the RBV-DOE and RBV-Gel was 27.949 ± 2.783 h and 37.374 ± 3.502 h, respectively. The mean peak serum concentration (C_max ) and area under the serum concentration-time curve from time zero to infinity (AUC_inf ) of RBV-DOE were 8340.000 ± 2562.577 ng/mL and 16 0095.430 ± 61 253.400 h·ng/mL, respectively. The C_max and AUC_inf of RBV-Gel were 15 300.000 ± 3764.306 ng/mL and 207526.260 ± 63656.390 h·ng/mL, respectively. The results of this study provided the index of side effect and pharmacokinetics of ribavirin in pigs, which should be considered before clinical application.

Further morphological observations on hearts with twisted atrioventricular connections (criss-cross hearts)

A superior and anterior location of the tricuspid valve in the setting of malalignment between the atrial and ventricular septal structures was the characteristic unifying morphologic feature of seven autopsied hearts with twisted atrioventricular connections. The peculiar angiocardiographic appearances of this lesion could be readily explained by the findings of unusual recesses in the right atrium, in the right ventricle, and in the left ventricle. The recess in the morphologically left ventricle was seen in each case at the right posterior part (or, in the hearts with left-handed ventricles, at the left part) of the chamber. Displacement of the right-sided atrioventricular valve far from the inferior caval vein (vena cava) had produced the recess in the morphologically right atrium; this feature was most prominent in the heart in which the atrioventricular connections were discordant. The recess within the right ventricular outflow tract was seen in four hearts, in all of which the inlet and apical trabecular components of the right ventricle were hypoplastic.

Regulation of fragile X mental retardation 1 protein by C-terminus of Hsc70-interacting protein depends on its phosphorylation status

The fragile X mental retardation 1 (FMR1) protein binds mRNA and acts as a negative regulator of translation. Lack of FMR1 causes the most common neurological disorder, fragile X syndrome, while its overexpression is associated with metastasis of breast cancer. Its activity has been well-studied in nervous tissue, but recent evidence as well as its role in cancer indicates that it also acts in other tissues. We have investigated the expression of FMR1 in brain and other tissues of mouse and examined its regulation. We detected expression of FMR1 in liver and heart tissues of mice as well as in brain tissue, supporting other contentions that it acts in non-nervous tissue. Expression of FMR1 inversely correlated with expression of the C-terminus of Hsc70-interacting protein (CHIP) and, based on the known activity of CHIP in protein homeostasis, we suggest that CHIP regulates expression of FMR1. CHIP ubiquitinated FMR1 for proteasomal degradation in a molecular chaperone-independent manner. FMR1 expression was reduced following treatment with okadaic acid, a phosphatase inhibitor, but not in CHIP-depleted cells. Also, a non-phospho FMR1 mutant was much less efficiently ubiquitinated by CHIP and had a longer half-life compared to either wild-type FMR or a phospho-mimic mutant. Taken together, our results demonstrate that CHIP regulates the levels of FMR1 as an E3 ubiquitin ligase in phosphorylation-dependent manner, suggesting that CHIP regulates FMR1-mediated translational repression by regulating the levels of FMR1.

Relationship among attention-deficit hyperactivity disorder, dietary behaviours and obesity

BACKGROUND

Attention-deficit hyperactivity disorder (ADHD) is one of the most common psychiatric disorders of childhood and can be associated with obesity. The aim of this study was to reveal the connection between ADHD symptoms, food habits and obesity.

METHODS

We examined 12 350 children (6010 boys, 6340 girls) from 27 elementary schools in Cheonan, the Republic of Korea. The study subjects were 5- to 13-year-old children (9.4 ± 1.7 years). Parents completed the DuPaul ADHD Rating Scale. Food habits were measured by a questionnaire adapted from the Korea Youth Risk Behavior Web-based Survey and a validated mini-dietary assessment tool. The full set of hypothesized associations was tested using covariance structural modelling.

RESULTS

The prevalence of ADHD was 7.6% and that of obesity was 4.5% in our study population. The data was well fit by the model. ADHD was associated with body mass index (BMI; standardized β = 0.086, P < 0.001). Bulimic dietary behaviours was related to BMI (standardized β = 0.548, P < 0.001). Socio-economic status was associated with BMI (standardized β = -0.017, P = 0.027).

CONCLUSION

Our analysis suggested that ADHD was a risk factor for obesity through dietary behavioural change and socio-economic status.

Cellular inhibitor of apoptosis protein 1 ubiquitinates endonuclease G but does not affect endonuclease G-mediated cell death

Inhibitors of Apoptosis Proteins (IAPs) are evolutionarily well conserved and have been recognized as the key negative regulators of apoptosis. Recently, the role of IAPs as E3 ligases through the Ring domain was revealed. Using proteomic analysis to explore potential target proteins of DIAP1, we identified Drosophila Endonuclease G (dEndoG), which is known as an effector of caspase-independent cell death. In this study, we demonstrate that human EndoG interacts with IAPs, including human cellular Inhibitor of Apoptosis Protein 1 (cIAP1). EndoG was ubiquitinated by IAPs in vitro and in human cell lines. Interestingly, cIAP1 was capable of ubiquitinating EndoG in the presence of wild-type and mutant Ubiquitin, in which all lysines except K63 were mutated to arginine. cIAP1 expression did not change the half-life of EndoG and cIAP1 depletion did not alter its levels. Expression of dEndoG 54310, in which the mitochondrial localization sequence was deleted, led to cell death that could not be suppressed by DIAP1 in S2 cells. Moreover, EndoG-mediated cell death induced by oxidative stress in HeLa cells was not affected by cIAP1. Therefore, these results indicate that IAPs interact and ubiquitinate EndoG via K63-mediated isopeptide linkages without affecting EndoG levels and EndoG-mediated cell death, suggesting that EndoG ubiquitination by IAPs may serve as a regulatory signal independent of proteasomal degradation.

Whole Body Vibration Reduces Inflammatory Bone Loss in a Lipopolysaccharide Murine Model

Whole body vibration (WBV) stimulation has a beneficial effect on the recovery of osteoporotic bone. We aimed to investigate the immediate effect of WBV on lipopolysaccharide (LPS)-mediated inflammatory bone loss by varying the exposure timing. Balb/C mice were divided into the following groups: control, LPS (L), and LPS with vibration (LV). The L and LV groups received LPS (5 mg/kg) by 2 intraperitoneal injections on days 0 and 4. The LV group was exposed to WBV (0.4 g, 45 Hz) either during LPS treatment (LV1) or after cessation of LPS injection (LV2) and then continued WBV treatment for 10 min/d for 3 d. Evaluation based on micro-computed tomography was performed 7 d after the first injection, when the L group showed a significant decrease in bone volume (-25.8%) and bone mineral density (-33.5%) compared with the control group. The LV2 group recovered bone volume (35%) and bone mineral density (19.9%) compared with the L group, whereas the LV1 group showed no improvement. This vibratory signal showed a suppressive effect on the LPS-mediated induction of inflammatory cytokines such as IL-1β or TNF-α in human mesenchymal stem cells in vitro. These findings suggest that immediate exposure to WBV after the conclusion of LPS treatment efficiently reduces trabecular bone loss, but WBV might be less effective during the course of treatment with inflammatory factor.

Development status of the 18 GHz superconducting electron cyclotron resonance ion source at National Fusion Research Institute

A new superconducting 18 GHz electron cyclotron resonance ion source is being developed at the National Fusion Research Institute in South Korea. This source will be dedicated for future application of highly charged ions in the area of matter interaction, diagnostic imaging, and probing. In this paper, we describe the status of the source development consisting of a double electrode biased disk, sputtering systems for metal ion production, diagnostic ports for the extraction region, a variable gap extraction-Einzel lens system, and a low energy beam transport system.

Prenatal diagnosis and outcome of absent pulmonary valve syndrome: contemporary single-center experience and review of the literature

OBJECTIVE

To review the anomaly spectrum of prenatally detected absent pulmonary valve syndrome (APVS) and the outcome after diagnosis. Previous fetal studies reported survival rates of ≤ 25% for patients with intended postnatal care.

METHODS

Clinical data and echocardiograms of 12 cases with a fetal diagnosis of APVS between 2000 and 2010 were analyzed in this retrospective single-center study. Collected parameters included: gestational age at referral, associated fetal abnormalities, cardiothoracic ratio, maximum diameters of pulmonary annulus and main and branch pulmonary arteries, ventricular dimensions and function as well as ventricular Doppler flows. Karyotyping included fluorescence in-situ hybridization (FISH) analysis for microdeletion 22q11.2.

RESULTS

Median gestational age at diagnosis was 24 weeks. Three subtypes of APVS were observed: (1) with tetralogy of Fallot (TOF) and no arterial duct (n = 10; 83%); (2) isolated, with a large arterial duct (n = 1; 8%); and (3) with tricuspid atresia, right ventricular dysplasia and a restricted duct (n = 1; 8%). The cardiothoracic ratio and pulmonary artery dimensions were increased in all cases. The karyotype was abnormal in 70% of fetuses with TOF and their mortality rate was significantly higher due to pregnancy termination (n = 3) or perinatal demise (n = 2) (hazard ratio, 5; 95% CI, 0.87-28.9; P = 0.015). Of seven live births with active postnatal care, six children (86%) were alive without residual respiratory symptoms at a median follow-up of 4.7 (range, 2.1-10.6) years.

CONCLUSION

Outcome after fetal diagnosis of APVS was significantly better in this study compared with those of previous fetal series, with a low mortality rate for actively managed patients.

Comparative rapid onset of efficacy between doxazosin gastrointestinal therapeutic system and tamsulosin in patients with lower urinary tract symptoms from benign prostatic hyperplasia: a multicentre, prospective, randomised study

AIMS

To compare the rapidity of improvement in lower urinary tract symptoms (LUTS) for the doxazosin gastrointestinal therapeutic system (GITS) and tamsulosin in benign prostatic hyperplasia (BPH) patients.

METHODS

A total of 207 patients were randomised to one of two groups for a 12-week daily treatment with doxazosin-GITS 4 mg or tamsulosin 0.2 mg. The primary end-point was to compare the early onsets of efficacy between the two drugs. This was assessed by analysing the changes from baseline in the total International Prostate Symptom Score (IPSS) in the early period of treatment. Secondary aims were to compare improvements in obstructive/irritative subscore and quality of life (QoL) score between the two groups, and to evaluate the adverse events (AEs) with the drugs.

RESULTS

After 12 weeks of treatment, both groups showed significant improvements in IPSS scores (total, obstructive and irritative subscores, QoL score) from baseline (p < 0.0001). However, the doxazosin-GITS group showed significantly greater improvements in total IPSS and obstructive subscore than the tamsulosin group in the early period (p < 0.05). Improvements in irritative subscore (within 4 weeks) and QoL score (during 12 weeks) were not significantly different between the groups. The incidences of AEs were similar between the groups.

CONCLUSION

In this study, doxazosin-GITS showed significantly more rapid onset of efficacy and similar AEs compared with tamsulosin in BPH patients with LUTS. We believe this will probably improve patient compliance. Future studies with a larger number of patients and a longer follow-up period will be required to confirm this.

A multicenter, randomized, placebo-controlled, double-blind phase II trial evaluating the optimal dose, efficacy and safety of LC 15-0444 in patients with type 2 diabetes

AIM

The objective of this study was to evaluate the optimal dose, efficacy and safety of a novel dipeptidyl peptidase-4 (DPP-IV) inhibitor, LC15-0444, in Korean subjects with type 2 diabetes mellitus treated by diet and exercise.

METHODS

This study was a double-blind, randomized, multicenter and parallel-group, dose-range finding study. We enrolled 145 patients (91 men and 54 women) with a median age of 53 years and a median body mass index of 25.1 kg/m(2) . The median baseline fasting plasma glucose (FPG) was 8.1 mmol/l, the median HbA1c was 7.9% and the median time since the diagnosis of diabetes was 3 years. After 2 weeks of an exercise/diet programme followed by 2 weeks of a placebo period, the subjects were randomized to one of the four following groups for a 12-week active treatment period: placebo and 50, 100 or 200 mg of LC15-0444.

RESULTS

All three doses of LC15-0444 significantly reduced the HbA1c from baseline compared to the placebo group (-0.06 vs. -0.98, -0.74 and -0.78% in the placebo and 50, 100 and 200 mg groups, respectively), without a significant difference between the doses. Subjects with a higher baseline HbA1c (≥8.5%) had a greater reduction in HbA1c. Insulin secretory function, as assessed using homeostasis model assessment-beta cell, C-peptide and the insulinogenic index, improved significantly with LC15-0444 treatment. Insulin sensitivity, as assessed using homeostasis model assessment-insulin resistance, also improved significantly after 12 weeks of treatment. The 50 and 200 mg groups had significantly reduced total cholesterol and low-density lipoprotein cholesterol levels at 12 weeks compared to the placebo group. No dosage of LC15-0444 affected weight or waist circumference. The incidences of adverse events were similar in all study subjects.

CONCLUSIONS

LC15-0444 monotherapy (50 mg for 12 weeks) improved the HbA1c, FPG level, oral glucose tolerance test results, β-cell function and insulin sensitivity measures, and was well tolerated in Korean subjects with type 2 diabetes.

The relationship between adipokines, metabolic parameters and insulin resistance in patients with metabolic syndrome and type 2 diabetes

This study was designed to investigate the relationship between adipokines in metabolic syndrome and insulin resistance. Sixty male and female subjects with or without metabolic syndrome and type 2 diabetes were included. The homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. Compared with lean control subjects, patients with metabolic syndrome and type 2 diabetes had lower circulating levels of total adiponectin and high molecular weight (HMW) adiponectin, and higher levels of leptin and interleukin-6 (IL-6). Total and HMW adiponectin and the adiponectin/leptin (A/L) ratio were negatively correlated with HOMA-IR. After adjusting for age and sex, leptin, IL-6 and tumour necrosis factor-alpha (TNF-alpha) were positively correlated with HOMA-IR. After also adjusting for body mass index, HOMA-IR was found to be independently associated with leptin, A/L ratio and TNF-alpha levels. In conclusion, decreased total adiponectin and HMW adiponectin and increased leptin and IL-6 levels are characteristic of patients with metabolic syndrome and type 2 diabetes.

Evaluation on simultaneous removal of particles and off-flavors using population balance for application of powdered activated carbon in dissolved air flotation process

Most of the water treatment plants applying the DAF process are faced with off-flavors control problems. For simultaneous control of particles of impurities and dissolved organics that cause pungent taste and odor in water, an effective method would be the simple application of powdered activated carbon (PAC) in the DAF process. A series of experiments were carried out to explore the feasibility for simultaneous removal of kaolin particles and organic compounds that produce off-flavors (2-MIB and geosmin). In addition, the flotation efficiency of kaolin and PAC particles adsorbing organics in the DAF process was evaluated by employing the population balance theory. The removal efficiency of 2-MIB and geosmin under the treatment condition with kaolin particles for simultaneous treatment was lower than that of the individual treatment. The decrease in the removal efficiency was probably caused by 2-MIB and geosmin remaining in the PAC particle in the treated water of DAF after bubble flotation. Simulation results obtained by the population balance model indicate, that the initial collision-attachment efficiency of PAC particles was lower than that of kaolin particles.

Chfr is linked to tumour metastasis through the downregulation of HDAC1

Chfr is a ubiquitin ligase that functions in the mitotic checkpoint by delaying entry into metaphase in response to mitotic stress. It has been suggested that Chfr is a tumour suppressor as Chfr is frequently silenced in human cancers. To better understand how Chfr activity relates to cell-cycle progression and tumorigenesis, we sought to identify Chfr-interacting proteins using affinity purification combined with mass spectrometry. Histone deacetylase 1 (HDAC1), which represses transcription by deacetylating histones, was newly isolated as a Chfr-interacting protein. Chfr binds and downregulates HDAC1 by inducing its polyubiquitylation, both in vitro and in vivo. Ectopic expression of Chfr in cancer cells that normally do not express it results in downregulation of HDAC1, leading to upregulation of the Cdk inhibitor p21(CIP1/WAF1) and the metastasis suppressors KAI1 and E-cadherin. Coincident with these changes, cells arrest in the G1 phase of the cell cycle and become less invasive. Collectively, our data suggest that Chfr functions as a tumour suppressor by regulating HDAC1.

Compact 10 GHz loopback arrayed-waveguide grating for high-fidelity optical arbitrary waveform generation

We demonstrate a high-performance optical arbitrary waveform shaper based on a single 10 GHz arrayed-waveguide grating with 64 loopback waveguides and integrated amplitude and phase modulators on each waveguide. The design is compact and self-aligning and allows for bidirectional operation. The device's complex transfer function is manipulated and measured over the full 640 GHz passband. To demonstrate optical arbitrary waveform shaping, high-fidelity 15-line shaped waveforms are measured with cross-correlation frequency-resolved optical gating.

Expression of Kir2.1 channels in astrocytes under pathophysiological conditions

Astrocyte ion channels participate in ionic homeostasis in the brain. Inward rectifying potassium channels (Kir channels) in astrocytes have been particularly implicated in K(+) homeostasis because of their high open probability at resting potential and their increased conductance at high concentrations of extracellular K(+). We examined the expression of the Kir2.1 subunit, one of the Kir channel subunits, in the mouse brain by immunohistochemistry. Kir2.1 channels were widely distributed throughout the brain, with high expression in the olfactory bulb and the cerebellum. Interestingly, they were abundantly expressed in astrocytes of the olfactory bulb, while astrocytes in other brain regions including the hippocampus did not show any detectable expression. However, Kir2.1 channel-expressing cells were dramatically increased in the hippocampus by kainic acid-induced seizure and the cells were glial fibrillary acidic protein (GFAP)-positive, which confirms that astrocytes in the hippocampus express Kir2.1 channels under pathological conditions. Our results imply that Kir2.1 channels in astrocyte may be involved in buffering K(+) against accumulated extracellular K(+) caused by neuronal hyperexcitability under phathophysiological conditions.

Hyperthermal neutral beam sources for material processing

Hyperthermal neutral beams have a great potential for material processes, especially for etching and thin film deposition for semiconductor and display fabrication as well as deposition for various thin film applications. Plasma-induced damage during plasma etching is a serious problem for manufacturing deep submicron semiconductor devices and is expected to be a problem for future nanoscale devices. Thermal and plasma-induced damage is also problematic for thin film depositions such as transparent conductive oxide films on organic light emitting diodes or flexible displays due to high temperature processes in plasma environments. These problems can be overcome by damage-free and low-temperature processes with hyperthermal neutral beams. We will present the status of the hyperthermal neutral beam development and the applications, especially, in semiconductor and display fabrication and introduce potential applications of thin film growing for optoelectronic devices such as light emitting diodes.

Translation initiation factor 4E (eIF4E) is regulated by cell death inhibitor, Diap1

Translation initiation factor 4E (eIF4E) is a key regulator of protein synthesis. Abnormal regulation of eIF4E is closely linked to oncogenic transformation. Several regulatory mechanisms affecting eIF4E are discussed, including transcriptional regulation, phosphorylation and binding of an inhibitor protein. However it is not clear how the level of eIF4E protein is regulated under basal conditions. Here we demonstrate that Diap1 (Drosophila Inhibitor of Apoptosis Protein), a cell death inhibitor, binds directly to eIF4E and poly-ubiquitinates it via its E3 ligase activity, promoting its proteasome-dependent degradation. Expression of Diap1 caused a reduction of Cyclin D1 protein level and inhibited the growth stimulation induced by overexpression of eIF4E. Taken together, our results suggest that the level of eIF4E protein is regulated by Diap1, and that IAPs may play a role in cap-dependent translation by regulating the level of eIF4E protein.

Association of BAF53 with mitotic chromosomes

The conversion of mitotic chromosome into interphase chromatin consists of at least two separate processes, the decondensation of the mitotic chromosome and the formation of the higher-order structure of interphase chromatin. Previously, we showed that depletion of BAF53 led to the expansion of chromosome territories and decompaction of the chromatin, suggesting that BAF53 plays an essential role in the formation of higher-order chromatin structure. We report here that BAF53 is associated with mitotic chromosomes during mitosis. Immunostaining with two different anti-BAF53 antibodies gave strong signals around the DNA of mitotic preparations of NIH3T3 cells and mouse embryo fibroblasts (MEFs). The immunofluorescent signals were located on the surface of mitotic chromosomes prepared by metaphase spread. BAF53 was also found in the mitotic chromosome fraction of sucrose gradients. Association of BAF53 with mitotic chromosomes would allow its rapid activation on the chromatin upon exit from mitosis.

Deubiquitination of Chfr, a checkpoint protein, by USP7/HAUSP regulates its stability and activity

Chfr, a mitotic stress checkpoint, plays an important role in cell cycle progression, tumor suppression and the processes that require the E3 ubiquitin ligase activity mediated by the RING finger domain. Chfr stimulates the formation of polyubiquitin chains by ub-conjugating enzymes, and induces the proteasome-dependent degradation of a number of cellular proteins including Plk1 and Aurora A. In this study, we identified USP7 (also known as HAUSP), which is a member of a family of proteins that cleave polyubiquitin chains and/or ubiquitin precursors, as an interacting protein with Chfr by immunoaffinity purification and mass spectrometry, and their interaction greatly increases the stability of Chfr. In fact, USP7 can remove ubiquitin moiety from the autoubiquitinated Chfr both in vivo and in vitro, which results in the accumulation of Chfr in the cell. Thus, our finding suggests that USP7-mediated deubiquitination of Chfr leads to its accumulation, which might be a key regulatory step for Chfr activation and that USP7 may play an important role in the regulation of Chfr-mediated cellular processes including cell cycle progression and tumor suppression.

The Drosophila inhibitor of apoptosis (IAP) DIAP2 is dispensable for cell survival, required for the innate immune response to gram-negative bacterial infection, and can be negatively regulated by the reaper/hid/grim family of IAP-binding apoptosis inducers

Many inhibitor of apoptosis (IAP) family proteins inhibit apoptosis. IAPs contain N-terminal baculovirus IAP repeat domains and a C-terminal RING ubiquitin ligase domain. Drosophila IAP DIAP1 is essential for the survival of many cells, protecting them from apoptosis by inhibiting active caspases. Apoptosis initiates when proteins such as Reaper, Hid, and Grim bind a surface groove in DIAP1 baculovirus IAP repeat domains via an N-terminal IAP-binding motif. This evolutionarily conserved interaction disrupts DIAP1-caspase interactions, unleashing apoptosis-inducing caspase activity. A second Drosophila IAP, DIAP2, also binds Rpr and Hid and inhibits apoptosis in multiple contexts when overexpressed. However, due to a lack of mutants, little is known about the normal functions of DIAP2. We report the generation of diap2 null mutants. These flies are viable and show no defects in developmental or stress-induced apoptosis. Instead, DIAP2 is required for the innate immune response to Gram-negative bacterial infection. DIAP2 promotes cytoplasmic cleavage and nuclear translocation of the NF-kappaB homolog Relish, and this requires the DIAP2 RING domain. Increasing the genetic dose of diap2 results in an increased immune response, whereas expression of Rpr or Hid results in down-regulation of DIAP2 protein levels. Together these observations suggest that DIAP2 can regulate immune signaling in a dose-dependent manner, and this can be regulated by IBM-containing proteins. Therefore, diap2 may identify a point of convergence between apoptosis and immune signaling pathways.

The Drosophila caspase Ice is important for many apoptotic cell deaths and for spermatid individualization, a nonapoptotic process

Caspase family proteases play important roles in the regulation of apoptotic cell death. Initiator caspases are activated in response to death stimuli, and they transduce and amplify these signals by cleaving and thereby activating effector caspases. In Drosophila, the initiator caspase Nc (previously Dronc) cleaves and activates two short-prodomain caspases, Dcp-1 and Ice (previously Drice), suggesting these as candidate effectors of Nc killing activity. dcp-1-null mutants are healthy and possess few defects in normally occurring cell death. To explore roles for Ice in cell death, we generated and characterized an Ice null mutant. Animals lacking Ice show a number of defects in cell death, including those that occur during embryonic development, as well as during formation of adult eyes, arista and wings. Ice mutants exhibit subtle defects in the destruction of larval tissues, and do not prevent destruction of salivary glands during metamorphosis. Cells from Ice animals are also markedly resistant to several stresses, including X-irradiation and inhibition of protein synthesis. Mutations in Ice also suppress cell death that is induced by expression of Rpr, Wrinkled (previously Hid) and Grim. These observations demonstrate that Ice plays an important non-redundant role as a cell death effector. Finally, we demonstrate that Ice participates in, but is not absolutely required for, the non-apoptotic process of spermatid differentiation.

Drosophila pink1 is required for mitochondrial function and interacts genetically with parkin

Parkinson's disease is the second most common neurodegenerative disorder and is characterized by the degeneration of dopaminergic neurons in the substantia nigra. Mitochondrial dysfunction has been implicated as an important trigger for Parkinson's disease-like pathogenesis because exposure to environmental mitochondrial toxins leads to Parkinson's disease-like pathology. Recently, multiple genes mediating familial forms of Parkinson's disease have been identified, including PTEN-induced kinase 1 (PINK1; PARK6) and parkin (PARK2), which are also associated with sporadic forms of Parkinson's disease. PINK1 encodes a putative serine/threonine kinase with a mitochondrial targeting sequence. So far, no in vivo studies have been reported for pink1 in any model system. Here we show that removal of Drosophila PINK1 homologue (CG4523; hereafter called pink1) function results in male sterility, apoptotic muscle degeneration, defects in mitochondrial morphology and increased sensitivity to multiple stresses including oxidative stress. Pink1 localizes to mitochondria, and mitochondrial cristae are fragmented in pink1 mutants. Expression of human PINK1 in the Drosophila testes restores male fertility and normal mitochondrial morphology in a portion of pink1 mutants, demonstrating functional conservation between human and Drosophila Pink1. Loss of Drosophila parkin shows phenotypes similar to loss of pink1 function. Notably, overexpression of parkin rescues the male sterility and mitochondrial morphology defects of pink1 mutants, whereas double mutants removing both pink1 and parkin function show muscle phenotypes identical to those observed in either mutant alone. These observations suggest that pink1 and parkin function, at least in part, in the same pathway, with pink1 functioning upstream of parkin. The role of the pink1-parkin pathway in regulating mitochondrial function underscores the importance of mitochondrial dysfunction as a central mechanism of Parkinson's disease pathogenesis.

Grim stimulates Diap1 poly-ubiquitination by binding to UbcD1

Diap1 is an essential Drosophila cell death regulator that binds to caspases and inhibits their activity. Reaper, Grim and Hid each antagonize Diap1 by binding to its BIR domain, activating the caspases and eventually causing cell death. Reaper and Hid induce cell death in a Ring-dependent manner by stimulating Diap1 auto-ubiquitination and degradation. It was not clear that how Grim causes the ubiquitination and degradation of Diap1 in Grim-dependent cell death. We found that Grim stimulates poly-ubiquitination of Diap1 in the presence of UbcD1 and that it binds to UbcD1 in a GST pull-down assay, so presumably promoting Diap1 degradation. The possibility that dBruce is another E2 interacting with Diap1 was examined. The UBC domain of dBruce slightly stimulated poly-ubiquitination of Diap1 in Drosophila extracts but not in the reconstitution assay. However Grim did not stimulate Diap1 poly-ubiquitination in the presence of the UBC domain of dBruce. Taken together, these results suggest that Grim stimulates the poly-ubiquitination and presumably degradation of Diap1 in a novel way by binding to UbcD1 but not to the UBC domain of dBruce as an E2.

Analysis of gene expression induced by microtubule-disrupting agents in HeLa cells using microarray

Microtubules are important cytoskeletal elements that have been shown to play a major role in many cellular processes because of their mechanical properties and/or their participation in various cell signaling pathways. Nocodazole is used as an effective microtubule-disrupting agent, and many recent studies have used it for the activation of spindle checkpoint. In this study, we sought to identify the potential nocodazole target genes by profiling the gene expression pattern in HeLa cells. When treated with 0.1ug/ml of nocodazole, cells were efficiently arrested in the mitotic phase. HeLa cells also showed a higher proportion of apoptosis after drug treatment for a prolonged period. By DNA chip assay, we discovered that 50 genes changed their expressions in the nocodazole-treated cells with a minimal 2.0-fold change at 18h post-treatment. The majority of the differentially expressed genes belonged to two functional groups--genes involved in transcription regulation and in cellular signaling. These observations could have significant implications for our understanding of the physiological and pathophysiological regulation of spindle disrupting agents in human cells.

An alarmingly high prevalence of diabetic nephropathy in Asian type 2 diabetic patients: the MicroAlbuminuria Prevalence (MAP) Study

AIM/HYPOTHESIS

Microalbuminuria represents the earliest clinical evidence of diabetic nephropathy and is a marker of increased cardiovascular morbidity and mortality. Its early detection allows the implementation of individualised and aggressive intervention programmes to reduce cardiovascular risk factors. There is limited information on the prevalence of microalbuminuria among hypertensive type 2 diabetic patients in Asia.

METHODS

This cross-sectional epidemiological study aimed to assess the prevalence of microalbuminuria and macroalbuminuria among consecutively screened hypertensive type 2 diabetic adult patients in 103 centres in 10 Asian countries or regions. Predictive factors for microalbuminuria and macroalbuminuria were characterised using a stepwise logistic regression model.

RESULTS

A total of 6,801 patients were enrolled and 5,549 patients constituted the per-protocol population (patients with bacteriuria and haematuria were excluded). The prevalence of microalbuminuria was 39.8% (39.2-40.5; 95% CI) and the prevalence of macroalbuminuria was 18.8% (18.2-19.3; 95% CI). Only 11.6% of the patients had systolic and diastolic blood pressure below the 130/80 mm Hg target. In the multivariate analyses, the predictive factors for the presence of microalbuminuria were age, BMI, systolic blood pressure and ethnic origin. The highlighted predictive factors for the presence of macroalbuminuria were age, sex, ethnic origin, BMI, duration of diabetes, presence of diabetic complications, intake of diuretics, intake of calcium channel blockers, diastolic and systolic blood pressure.

CONCLUSIONS/INTERPRETATION

The high prevalence (58.6%) of micro or macroalbuminuria observed in these patients is alarming and indicates an impending pandemic of diabetic cardiovascular and renal diseases in Asia with its potential economic consequences.

Expression of the intermediate filament vimentin in proliferating duct cells as a marker of pancreatic precursor cells

OBJECTIVES

The expression of the intermediate filament (IF) vimentin, usually considered a marker of mesenchymal cells, has been observed in the epithelial cells during embryogenesis, carcinogenesis, and dedifferentiation, suggesting that it might be useful as a marker of proliferating precursor cells in the pancreas.

METHODS

Rat pancreata at E18 and at different time points after partial pancreatectomy (Px) and human and neonatal pig pancreatic tissue sections and monolayer cultured pancreatic duct cells were observed. All tissues were simultaneously immunostained with pancytokeratin and vimentin antibodies. In costained duct cells, PDX-1 or PCNA expression was also analyzed using confocal microscope images.

RESULTS

In the rat embryonic pancreas at E18, all epithelial cells that formed ductlike structures expressed both cytokeratin and vimentin IF, whereas no duct cells costained for IF in the adult rat or neonatal pig pancreas. Such costaining reappeared in the following order: common pancreatic duct, main ducts, foci of regeneration and then disappeared completely at 30 days after Px. In humans, costaining was found in only 1 diabetic patient's pancreatic section, which was accompanied by massive duct cell proliferation. In monolayer culture, most of the duct cells of human and neonatal pigs coexpressed both IF proteins. Only a few costained duct cells also expressed PDX-1, and most of those cells were also stained with PCNA in rat embryonic pancreas and regenerating foci after partial Px.

CONCLUSIONS

Vimentin IF expression might be a useful marker for pancreatic precursor cells and could be used to investigate the concept of the dedifferentiation of fully matured duct cells during the process of the beta-cell neogenesis.

Rhodococcus equi pneumonia in a heart transplant recipient in Korea, with emphasis on microbial diagnosis

Rhodococcus equi is an opportunistic pathogen that usually causes infection in immunocompromised hosts. A heart transplant recipient who had been treated with amphotericin B for pulmonary aspergillosis showed newly developed multiple nodules with a central necrotic area in the right lower lobes. Cultures of several blood samples and an aspirate of the lung nodule yielded a Gram-positive coccobacillary bacterium, which was initially reported as a Corynebacterium species, but was later identified as R. equi by API CORYNE (bioMerieux SA, Marcy l'Etoile, France) and by demonstrating the production of 'equi factor'. The identification was subsequently confirmed by an R. equi-specific polymerase chain reaction (PCR). The patient was successfully treated with ciprofloxacin and azithromycin for 14 weeks. This is the first documented case of R. equi infection in Korea. There is a possibility of underestimation of R. equi infections due to the misidentification of the organism as a contaminating diphtheroid. Because R. equi will not respond to the conventional empirical therapy, the microbiology laboratory should identify R. equi in a timely manner. R. equi-specific PCR will be a useful confirmatory test in human infection.

Reaper is regulated by IAP-mediated ubiquitination

In most cases, apoptotic cell death culminates in the activation of the caspase family of cysteine proteases, leading to the orderly dismantling and elimination of the cell. The IAPs (inhibitors of apoptosis) comprise a family of proteins that oppose caspases and thus act to raise the apoptotic threshold. Disruption of IAP-mediated caspase inhibition has been shown to be an important activity for pro-apoptotic proteins in Drosophila (Reaper, HID, and Grim) and in mammalian cells (Smac/DIABLO and Omi/HtrA2). In addition, in the case of the fly, these proteins are able to stimulate the ubiquitination and degradation of IAPs by a mechanism involving the ubiquitin ligase activity of the IAP itself. In this report, we show that the Drosophila RHG proteins (Reaper, HID, and Grim) are themselves substrates for IAP-mediated ubiquitination. This ubiquitination of Reaper requires IAP ubiquitin-ligase activity and a stable interaction between Reaper and the IAP. Additionally, degradation of Reaper can be blocked by mutating its potential ubiquitination sites. Most importantly, we also show that regulation of Reaper by ubiquitination is a significant factor in determining its biological activity. These data demonstrate a novel function for IAPs and suggest that IAPs and Reaper-like proteins mutually control each other's abundance.

A case of biphenotypic blast crisis of unclassified myeloproliferative disorder

We report a first case of biphenotypic blast crisis of unclassified myeloproliferative disorder (MPD). A 20-year-old patient presented with fever, splenomegaly, marked leukocytosis (603 x 10(3)/ micro l), and blasts in the peripheral blood. Since Ph chromosome and bcr-abl gene rearrangement were absent, the diagnosis of an unclassified MPD in the blast crisis phase was established. Immunophenotyping confirmed a biphenotypic crisis of myeloid and T-lymphoid antigens. The patient went into a complete remission after chemotherapy, but marked granulocytic hyperplasia (M:E ratio of 5.7) and 90% cellularity remained. Blast crisis recurred during subsequent intensification chemotherapy and the patient did not go into a complete remission regardless of the intense chemotherapy. The blast crisis transformed from unclassified MPD had a grave prognosis as it responded poorly to chemotherapy. This unique blast crisis is distinguishable from the blast crisis of chronic myelogenous leukemia.

A pathway of signals regulating effector and initiator caspases in the developing Drosophila eye

Regulated cell death and survival play important roles in neural development. Extracellular signals are presumed to regulate seven apparent caspases to determine the final structure of the nervous system. In the eye, the EGF receptor, Notch, and intact primary pigment and cone cells have been implicated in survival or death signals. An antibody raised against a peptide from human caspase 3 was used to investigate how extracellular signals controlled spatial patterning of cell death. The antibody crossreacted specifically with dying Drosophila cells and labelled the activated effector caspase Drice. It was found that the initiator caspase Dronc and the proapoptotic gene head involution defective were important for activation in vivo. Dronc may play roles in dying cells in addition to activating downstream effector caspases. Epistasis experiments ordered EGF receptor, Notch, and primary pigment and cone cells into a single pathway that affected caspase activity in pupal retina through hid and Inhibitor of Apoptosis Proteins. None of these extracellular signals appeared to act by initiating caspase activation independently of hid. Taken together, these findings indicate that in eye development spatial regulation of cell death and survival is integrated through a single intracellular pathway.

Hid, Rpr and Grim negatively regulate DIAP1 levels through distinct mechanisms

Inhibitor of apoptosis (IAP) proteins suppress apoptosis and inhibit caspases. Several IAPs also function as ubiquitin-protein ligases. Regulators of IAP auto-ubiquitination, and thus IAP levels, have yet to be identified. Here we show that Head involution defective (Hid), Reaper (Rpr) and Grim downregulate Drosophila melanogaster IAP1 (DIAP) protein levels. Hid stimulates DIAP1 polyubiquitination and degradation. In contrast to Hid, Rpr and Grim can downregulate DIAP1 through mechanisms that do not require DIAP1 function as a ubiquitin-protein ligase. Observations with Grim suggest that one mechanism by which these proteins produce a relative decrease in DIAP1 levels is to promote a general suppression of protein translation. These observations define two mechanisms through which DIAP1 ubiquitination controls cell death: first, increased ubiquitination promotes degradation directly; second, a decrease in global protein synthesis results in a differential loss of short-lived proteins such as DIAP1. Because loss of DIAP1 is sufficient to promote caspase activation, these mechanisms should promote apoptosis.

Juniper oil inhibits the heat shock-induced apoptosis via preventing the caspase-3 activation in human astrocytes CCF-STTG1 cells

BACKGROUND

Brain astrocytes play a pivotal role in neuronal activities.

METHODS

An investigation was undertaken to determine whether juniper oil inhibits heat shock-induced apoptosis of astrocytes.

RESULTS

Juniper oil inhibited the heat shock-induced apoptosis in human astrocyte CCF-STTG1 cells. Pretreatment of the cells with juniper oil inhibited the heat shock-induced DNA fragmentation and condensation of nuclear chromatin. Juniper oil alone did not affect the apoptosis. Juniper oil inhibited the heat shock-induced caspase-3 activation and poly-ADP-ribose polymerase (PARP) fragmentation in the human astrocytes.

CONCLUSIONS

Juniper oil may inhibit the apoptosis of astrocytes by preventing the caspase-3 activation.

A hearing preservation technique for the resection of extensive jugular foramen tumors

OBJECTIVE

To describe a modified surgical approach for patients who maintain hearing function with jugular foramen tumors that extend to the posterior cranial fossa and the neck.

STUDY DESIGN

A retrospective review of 6 patients with jugular foramen tumors that were resected by a combined suboccipital and infralabyrinthine-transcervicomastoid approach.

METHODS

A combined suboccipital and infralabyrinthine-transcervicomastoid approach is characterized as follows: 1) There is no ablation of ear structures except the infralabyrinthine mastoid bone; the auricle is retracted anteriorly while preserving the bony wall and skin of the ear canal. 2) After superficial parotidectomy, a limited length of nerve VII from the intratemporal vertical segment is rerouted to divisions of the parotid portion. 3) The tumor is removed along with the internal jugular vein and sigmoid sinus, then the extended intracranial mass is resected through an additional suboccipital approach.

RESULTS

Five of the 6 patients had complete removal of all gross tumors. There were no major complications or mortalities. The preoperative levels of hearing were preserved in 5 of the 6 patients. Favorable facial function in the immediate postoperative period was noted in 4 of the 6 patients. Incomplete paralysis of 2 patients recovered eventually.

CONCLUSION

We propose that a combined suboccipital and infralabyrinthine-transcervicomastoid approach to the jugular foramen can provide sufficient exposure to resect most dumbbell-shaped tumors, and it could be the initial treatment of choice for patients with remnant hearing.

Tracheal compression by elongated aortic arch in patients with congenitally corrected transposition of the great arteries

We investigate the tracheal compression by aortic arch in patients with congenitally corrected transposition of the great arteries. Fourteen patients whose ascending aorta was connected to descending aorta on the contralateral side were divided into two groups according to the severity of tracheal compression on lateral angiogram: group 1 (stenosis > or = 50%, eight patients) and group 2 (stenosis < 50%, six patients). We compared the following variables between the groups: aortic size, lateral displacement of ascending aorta, retrosternal space, and contour of aortic arch. Spiral computed tomography (CT) was done in five patients of group 1. The ratio between measured and normal diameters of ascending aorta of group 1 was significantly larger than that of group 2 (1.57 +/- 0.14 compared to 1.19 +/- 0.26, p = 0.014). There was linear correlation between the tracheal compression and aortic size (r = 0.69, p = 0.001). The ascending aorta was positioned more laterally and the aortic arch was located more posteriorly in group 1. In four patients with decreased tracheal compression after surgery, aortic size decreased and the ascending aorta restored its anterior position. Spiral CT showed transversely oriented aortic arch and severe tracheal compression in the anteroposterior direction by aortic arch. The tracheal compression by aortic arch in corrected transposition is common when the descending aorta is located on the contralateral side of the ascending aorta. Aortic size, posterior position, elongation, and end-on appearance of the aortic arch are the useful predictors of tracheal compression.

The activation of PI 3-K and PKC zeta in PMA-induced differentiation of HL-60 cells

The human myelocytic leukemia cell line HL-60 is a useful model for the study of cellular differentiation. Phorbol 12-myristate 13-acetate (PMA) induces the monocyte/macrophage-like differentiation of HL-60 cells and results in growth arrest, increasing adherence. In PMA-induced differentiation of HL-60 cells, phosphoinositide 3-kinase (PI 3-K) activity was measured as phosphatidylinositol3P recovery from phosphatidylinositol by in vitro kinase assay. PI 3-K activity was increased in HL-60 cells that were stimulated by 20 nM PMA and the activity was inhibited by pretreatment with 20 microM LY294002, a specific inhibitor of PI 3-K. Members of the protein kinase C (PKC) family have been suggested to be one of the downstream targets of PI 3-K. PKC zeta is one of the atypical PKCs, non-diacylglycerol-responsive PKCs, and the activity was measured by the ability of phosphorylation onto myelin basic protein. PMA also induced the activation of PKC zeta during monocytic differentiation of HL-60 cells, and LY294002-pretreated cells failed to induce PKC zeta activation. The activity of PI 3-K is essential for PKC zeta activation, and LY294002 blocks both monocytic differentiation of HL-60 cells and activation of PKC zeta during PMA-induced cell differentiation. This implies that activated PI 3-K subsequently stimulates the PKC zeta in the process of PMA-induced monocytic differentiation.