High cortisol levels are associated with oxidative stress and mortality in maintenance hemodialysis patients

Background

Chronic stimulation of the mineralocorticoid receptor has been suggested as one of the potential causes of cardiovascular events and death in patients with end-stage renal disease. This observational cohort study was performed to demonstrate that serum cortisol might be a predictive marker for patient mortality and to evaluate its association with oxidized low-density lipoprotein (oxLDL) in hemodialysis (HD) patients.

Methods

Patients receiving HD three times a week were screened for enrollment at two institutions. Baseline cortisol levels were measured before each HD session, and the patients were divided into two groups according to the median value of serum cortisol before analysis. The baseline characteristics and laboratory values of the high and low cortisol groups were compared. Serum cortisol, adrenocorticotropic hormone, renin, aldosterone, and oxLDL were measured in 52 patients to evaluate the effect of oxidative stress on serum cortisol levels.

Results

A total of 133 HD patients were enrolled in this cohort study. Compared to the patients with low serum cortisol levels, the patients with high serum cortisol levels (baseline cortisol ≥ 10 μg/dL) showed higher rates of cardiovascular disease (59.7% vs. 39.4%, P=0.019) and left ventricular systolic dysfunction (LVSD) (25.9% vs. 8.0%, P=0.016). The patients in the high cortisol group demonstrated higher all-cause mortality than those in the low cortisol group. The serum cortisol level was an independent risk factor for patient mortality (hazard ratio 1.234, 95% confidence interval 1.022-1.49, P=0.029). Among the 52 patients with oxLDL measurements, oxLDL was an independent risk factor for elevated serum cortisol levels (Exp(B) 1.114, P=0.013) and LVSD (Exp(B) 12.308, P=0.045). However, plasma aldosterone levels did not affect serum cortisol levels.

Conclusions

Serum cortisol is a useful predictive marker for all-cause death among patients receiving HD. OxLDL is an independent marker for elevated serum cortisol among HD patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02722-w.

Suicide associated with COVID-19 infection: an immunological point of view

OBJECTIVE

Coronavirus disease 2019 (COVID-19) is a pandemic and leading cause of death. Beyond the deaths directly caused by the virus and the suicides related to the psychological response to the dramatic changes as socioeconomic related to the pandemic, there might also be suicides related to the inflammatory responses of the infection. Infection induces inflammation as a cytokine storm, and there is an increasing number of studies that report a relationship between infection and suicide.

MATERIALS AND METHODS

We searched the World Health Organization status report and the PubMed database for keywords (COVID-19, suicide, infection, inflammation, cytokines), and reviewed five cytokine pathways between suicide and inflammation using two meta-analyses and two observational studies starting from November 31, 2020, focusing on the relationship between suicide and inflammation by infection. First, we discussed existing evidence explaining the relationship between suicidal behaviors and inflammation. Second, we summarized the inflammatory features found in COVID-19 patients. Finally, we highlight the potential for these factors to affect the risk of suicide in COVID-19 patients.

RESULTS

Patients infected with COVID-19 have high amounts of IL-1β, IFN-γ, IP10, and MCP1, which may lead to Th1 cell response activation. Also, Th2 cytokines (e.g., IL-4 and IL-10) were increased in COVID-19 infection. In COVID-19 patients, neurological conditions, like headache, dizziness, ataxia, seizures, and others have been observed.

CONCLUSIONS

COVID-19 pandemic can serve as a significant environmental factor contributing directly to increased suicide risk; the role of inflammation by an infection should not be overlooked.

Malnutrition, inflammation, progression of vascular calcification and survival: Inter-relationships in hemodialysis patients

Background and aims

Malnutrition and inflammation are closely linked to vascular calcification (VC), the severity of which correlate with adverse outcome. However, there were few studies on the interplay between malnutrition, inflammation and VC progression, rather than VC presence per se. We aimed to determine the relationship of malnutrition, inflammation, abdominal aortic calcification (AAC) progression with survival in hemodialysis (HD) patients.

Methods

Malnutrition and inflammation were defined as low serum albumin (< 40 g/L) and high hs-CRP (≥ 28.57 nmol/L), respectively. We defined AAC progression as an increase in AAC score using lateral lumbar radiography at both baseline and one year later. Patients were followed up to investigate the impact of AAC progression on all-cause and cardiovascular mortality.

Results

AAC progressed in 54.6% of 97 patients (mean age 58.2±11.7 years, 41.2% men) at 1-year follow-up. Hypoalbuminemia (Odds ratio 3.296; 95% confidence interval 1.178–9.222), hs-CRP (1.561; 1.038–2.348), low LDL-cholesterol (0.976; 0.955–0.996), and the presence of baseline AAC (10.136; 3.173–32.386) were significant risk factors for AAC progression. During the mean follow-up period of 5.9 years, 38(39.2%) patients died and 27(71.0%) of them died of cardiovascular disease. Multivariate Cox regression analysis adjusted for old age, diabetes, cardiovascular history, and hypoalbuminemia determined that AAC progression was an independent predictor of all-cause mortality (2.294; 1.054–4.994).

Conclusions

Malnutrition and inflammation were significantly associated with AAC progression. AAC progression is more informative than AAC presence at a given time-point as a predictor of all-cause mortality in patients on maintenance HD.

The relationship between intradialytic hypotension and vascular calcification in hemodialysis patients

Background

Vascular calcification is associated with structural and functional abnormality of the heart and blood vessels. We investigated the relationship between intradialytic hypotension (IDH) and vascular calcification in hemodialysis (HD) patients, and their impacts on cardiovascular events (CVEs).

Method

We enrolled 191 maintenance HD patients who underwent plain abdomen radiography for abdominal aortic calcification score (AACS). A nadir systolic blood pressure (BP) < 90 mm Hg or the requirement of bolus fluid administration was required to quantify the hypotension diagnosis. IDH was defined as > 2 hypotension episodes during 10 HD treatments.

Results

Among the 191 patients, IDH occurred in 32. AACS was higher in the IDH group compared with the no-IDH group (8.4 ± 6.0 vs. 4.9 ± 5.2, respectively; P = 0.001). High AACS was an independent risk factor after adjustment for age, diabetes mellitus, ultrafiltration, diastolic BP, and calcium level (odds ratio (OR) = 1.09, 95% CI = 1.01–1.18; P = 0.03). Patients with both IDH and AACS ≧ 4 had the highest cumulative CVE rate (27.9%, P = 0.008) compared with 11.2%, 12.5%, and 6% for those with AACS ≧ 4 only, with IDH only, and neither, respectively. In multivariate analysis, the presence of both IDH and AACS ≧ 4 was a significant predictor of CVE (hazard ratio (HR) = 2.84, 95% CI = 1.04–7.74, P = 0.04).

Conclusion

IDH is associated with abdominal aortic calcification and is an independent risk factor for IDH. Both IDH and high AACS were significant predictors of CVE.

Extracellular Fluid/Intracellular Fluid Volume Ratio as a Novel Risk Indicator for All-Cause Mortality and Cardiovascular Disease in Hemodialysis Patients

Background

In hemodialysis patients, fluid overload and malnutrition are accompanied by extracellular fluid (ECF) expansion and intracellular fluid (ICF) depletion, respectively. We investigated the relationship between ECF/ICF ratio (as an integrated marker reflecting both fluid overload and malnutrition) and survival and cardiovascular disease (CVD) in the context of malnutrition-inflammation-arteriosclerosis (MIA) complex.

Methods

Seventy-seven patients from a single hemodialysis unit were prospectively enrolled. The ECF/ICF volume was measured by segmental multi-frequency bioimpedance analysis. MIA and volume status were measured by serum albumin, C-reactive protein (CRP), pulse wave velocity (PWV) and plasma B-type natriuretic peptide (BNP), respectively.

Results

The mean ECF/ICF ratio was 0.56±0.06 and the cut-off value for maximum discrimination of survival was 0.57. Compared with the low ECF/ICF group, the high ECF/ICF group (ratio≥0.57, 42%) had higher all-cause mortality, CVD, CRP, PWV, and BNP, but lower serum albumin. During the 5-year follow-up, 24 all-cause mortality and 38 CVD occurred (18 and 24, respectively, in the high ECF/ICF group versus 6 and 14 respectively in the low ECF/ICF group, P<0.001). In the adjusted Cox analysis, the ECF/ICF ratio nullifies the effects of the MIA and volume status on survival and CVD and was an independent predictor of all-cause mortality and CVD: hazard ratio (95% confidence interval); 1.12 (1.01–1.25) and 1.09 (1.01–1.18) for a 0.01 increase in the ECF/ICF ratio. The degree of malnutrition (albumin), inflammation (CRP), arteriosclerosis (PWV), and fluid overload (BNP) were correlated well with the ECF/ICF ratio.

Conclusions

Hemodialysis patients with high ECF/ICF ratio are not only fluid overloaded, but malnourished and have stiff artery with more inflammation. The ECF/ICF ratio is highly related to the MIA complex, and is a major risk indicator for all-cause mortality and CVD.

Novel fabrication method of the peritoneal dialysis filter using silk fibroin with urease fixation system

During the last decade, there has been a great advance in the kidney dialysis system by wearable artificial kidney (WAK) system for end-stage renal disease patients. Uremic solute removal and water regeneration system are the most prerequisite for WAK to work properly. In this study, we designed a filtering membrane system by using immobilized urease silk fibroin filter and evaluated its comparative effectiveness with a PVDF filtering system in peritoneal dialysate regeneration system by urea removal efficacy. We evaluated this membrane's characteristic and performances by conducting SEM-EDX analyze, water-binding abilities and porosity test, removal abilities of urea, cytotoxicity assay and enzyme activity assay. Under the condition for optimization of urease, the percentage removal of urea was about 40% and 60% in 50 mg/dL urea solution by urease immobilized PVDF and silk fibroin scaffolds, respectively. The batch experimental result showed that immobilized filter removed more than 50% of urea in 50 mg/dL urea solution. In addition silk fibroin with urease filter removed 90 percent of urea in the peritoneal dialysate after 24 h filtration. We suggest that silk fibroin with urease fixation filter can be used more effectively for peritoneal dialysate regeneration system, which have hydrophilic property and prolonged enzyme activity. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2136-2144, 2017.

Clinical significance of serum YKL-40 in Behçet disease

BACKGROUND

Serum YKL-40 is an inflammatory biomarker of endothelial dysfunction and may play a role in the inflammatory process of Behçet disease (BD).

OBJECTIVES

Serum YKL-40 levels were evaluated in patients with BD in order to identify associations with other inflammatory cytokines and establish laboratory parameters. Serum YKL-40 levels were also compared with BD clinical features and disease activity.

METHODS

In total, 112 patients with BD and 45 age- and sex-matched healthy volunteers were included. Disease activity was assessed with BD Current Activity Form score and Electronic Medical Record-based Activity Index (EMRAI) score.

RESULTS

Serum YKL-40 levels were significantly higher in patients with BD (median 41·88, range 12·52-171·30 ng mL(-1) ) than in healthy volunteers (median 20·92, range 5·01-64·20 ng mL(-1) ; P < 0·01). The cut-off value for YKL-40 (30·005 ng mL(-1) ) was determined from the receiver operating characteristic curve. EMRAI scores and the proportion of patients in the active phase of BD presenting with two or more major criteria were significantly higher in patients with elevated YKL-40 levels (P = 0·04 and P = 0·04, respectively). A statistically significant elevation in YKL-40 levels was observed in patients with active BD compared with patients with inactive BD (P = 0·05). Serum YKL-40 values were positively correlated with interleukin-6 and EMRAI scores (both P = 0·04), indicating that serum YKL-40 levels are increased in patients with BD and positively correlate with disease activity.

CONCLUSIONS

YKL-40 may play a role in the pathophysiology of BD and provide a useful marker for monitoring patients with BD.

Post calibration of the two-dimensional electron cyclotron emission imaging instrument with electron temperature characteristics of the magnetohydrodynamic instabilities

The electron cyclotron emission imaging (ECEI) instrument is widely used to study the local electron temperature (Te) fluctuations by measuring the ECE intensity IECE ∝ Te in tokamak plasmas. The ECEI measurement is often processed in a normalized fluctuation quantity against the time averaged value due to complication in absolute calibration. In this paper, the ECEI channels are relatively calibrated using the flat Te assumption of the sawtooth crash or the tearing mode island and a proper extrapolation. The 2-D relatively calibrated electron temperature (Te,rel) images are reconstructed and the displacement amplitude of the magnetohydrodynamic modes can be measured for the accurate quantitative growth analysis.

Quasi 3D ECE imaging system for study of MHD instabilities in KSTAR

A second electron cyclotron emission imaging (ECEI) system has been installed on the KSTAR tokamak, toroidally separated by 1/16th of the torus from the first ECEI system. For the first time, the dynamical evolutions of MHD instabilities from the plasma core to the edge have been visualized in quasi-3D for a wide range of the KSTAR operation (B0 = 1.7∼3.5 T). This flexible diagnostic capability has been realized by substantial improvements in large-aperture quasi-optical microwave components including the development of broad-band polarization rotators for imaging of the fundamental ordinary ECE as well as the usual 2nd harmonic extraordinary ECE.

The prevention of contrast-induced nephropathy by simultaneous hemofiltration during coronary angiographic procedures: a comparison with periprocedural hemofiltration

BACKGROUND

Periprocedural (6 h pre- and 24 h post-angiography) hemofiltration appears to effectively prevent contrast-induced nephropathy (CIN) in chronic kidney disease (CKD) patients undergoing coronary angiography. However, this procedure over-uses medical resources, and the cessation of hemofiltration during coronary angiography results in persistent renal injury. In comparison, simultaneous hemofiltration performed only during coronary angiography requires fewer medical resources and can provide instantaneous protection against CIN.

METHODS

Sixty-eight CKD patients (serum creatinine, 2.51±1.15 mg/dL) undergoing coronary angiography were randomized in a 1:2 ratio to receive either periprocedural (n=23) or simultaneous (n=45) hemofiltration. The expected CIN rate was similar for the two groups (41.3% versus 40.0%, p=0.769).

RESULTS

On day 3 after contrast exposure, four and seven patients in the periprocedural and simultaneous groups, respectively experienced CIN (17.4% versus 15.6%, p=0.846). On days 5-30, seven and three patients in the periprocedural and simultaneous groups, respectively experienced CIN (30.4% versus 6.7%, p=0.009). The serum creatinine levels of patients in the periprocedural group transiently decreased on day 1 and persistently increased during days 5-30 compared with the simultaneous group. This difference between the two groups in terms of creatinine levels over time was statistically significant (F statistic=6.830; p=0.001, by ANCOVA). The cost of hemofiltration was doubled in the periprocedural group ($1066±83 versus $504±40, p<0.001).

CONCLUSIONS

Simultaneous hemofiltration provide equal early (day 3) and better late-stage (days 5-30) renal protection against CIN at a significantly lower cost compared with periprocedural hemofiltration.

Distal renal tubular acidosis associated with Sjogren syndrome

Renal tubular acidosis is a common cause of normal anion gap metabolic acidosis but these disorders can be easily missed or misdiagnosed. We highlight the approach to assessing renal tubular acidosis by discussing a case study with a temporal data set collected over more than 5 weeks. We highlight the principles and the necessary information required for a diagnosis of classic distal renal tubular acidosis. We also briefly review several aspects of type 1 renal tubular acidosis related to autoimmune disease, drugs and thyroid disorders.

Toroidal mode number estimation of the edge-localized modes using the KSTAR 3-D electron cyclotron emission imaging system

A new and more accurate technique is presented for determining the toroidal mode number n of edge-localized modes (ELMs) using two independent electron cyclotron emission imaging (ECEI) systems in the Korea Superconducting Tokamak Advanced Research (KSTAR) device. The technique involves the measurement of the poloidal spacing between adjacent ELM filaments, and of the pitch angle α* of filaments at the plasma outboard midplane. Equilibrium reconstruction verifies that α* is nearly constant and thus well-defined at the midplane edge. Estimates of n obtained using two ECEI systems agree well with n measured by the conventional technique employing an array of Mirnov coils.

Automated registration of optical coherence tomography and dermoscopy in the assessment of sub-clinical spread in basal cell carcinoma

Optical coherence tomography (OCT) has been shown to be of clinical value in imaging basal cell carcinoma (BCC). A novel dual OCT-video imaging system, providing automated registration of OCT and dermoscopy, has been developed to assess the potential of OCT in measuring the degree of sub-clinical spread of BCC. Seventeen patients selected for Mohs micrographic surgery (MMS) for BCC were recruited to the study. The extent of BCC infiltration beyond a segment of the clinically assessed pre-surgical border was evaluated using OCT. Sufficiently accurate (<0.5 mm) registration of OCT and dermoscopy images was achieved in 9 patients. The location of the OCT-assessed BCC border was also compared with that of the final surgical defect. Infiltration of BCC across the clinical border ranged from 0 mm to >2.5 mm. In addition, the OCT border lay between 0.5 mm and 2.0 mm inside the final MMS defect in those cases where this could be assessed. In one case, where the final MMS defect was over 17 mm from the clinical border, OCT showed >2.5 mm infiltration across the clinical border at the FOV limit. These results provide evidence that OCT allows more accurate assessment of sub-clinical spread of BCC than clinical observation alone. Such a capability may have clinical value in reducing the number of surgical stages in MMS for BCC. There may also be a role for OCT in aiding the selection of patients most suitable for MMS.

Catechin-capped gold nanoparticles: green synthesis, characterization, and catalytic activity toward 4-nitrophenol reduction

An eco-friendly approach is described for the green synthesis of gold nanoparticles using catechin as a reducing and capping agent. The reaction occurred at room temperature within 1 h without the use of any external energy and an excellent yield (99%) was obtained, as determined by inductively coupled plasma mass spectrometry. Various shapes of gold nanoparticles with an estimated diameter of 16.6 nm were green-synthesized. Notably, the capping of freshly synthesized gold nanoparticles by catechin was clearly visualized with the aid of microscopic techniques, including high-resolution transmission electron microscopy, atomic force microscopy, and field emission scanning electron microscopy. Strong peaks in the X-ray diffraction pattern of the as-prepared gold nanoparticles confirmed their crystalline nature. The catalytic activity of the as-prepared gold nanoparticles was observed in the reduction of 4-nitrophenol to 4-aminophenol in the presence of NaBH4. The results suggest that the newly prepared gold nanoparticles have potential uses in catalysis.

Earthworm extracts utilized in the green synthesis of gold nanoparticles capable of reinforcing the anticoagulant activities of heparin

Gold nanoparticles were obtained using a green synthesis approach with aqueous earthworm extracts without any additional reducing or capping agents. The gold nanoparticles were characterized using UV-visible spectrophotometry, high-resolution transmission electron microscopy, atomic force microscopy, field emission scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and inductively coupled plasma mass spectrometry. The anticoagulant activity of the gold nanoparticles was assessed using the activated partial thromboplastin time and was mildly enhanced by combining the gold nanoparticles with heparin. In addition to the generation of spherical nanoparticles with an average diameter of 6.13 ± 2.13 nm, cubic and block-shaped nanoparticles with an average aspect ratio, defined as the length divided by width, of 1.47 were also observed.

Rhabdomyolysis and acute kidney injury associated with hypothyroidism and statin therapy

Rhabdomyolysis is a syndrome involving the breakdown of skeletal muscle that causes myoglobin and other intracellular proteins to leak into the circulatory system, resulting in organ injury including acute kidney injury. We report a case of statin-induced rhabdomyolysis and acute kidney injury that developed in a 63-year-old woman with previously undiagnosed hypothyroidism. Untreated hypothyroidism may have caused her hypercholesterolemia requiring statin treatment, and it is postulated that statin-induced muscle injury was aggravated by hypothyroidism resulting in her full-blown rhabdomyolysis. Although this patient was successfully treated with continuous venovenous hemofiltration and L-thyroxin replacement, rhabdomyolysis with acute kidney injury is a potentially life-threatening disorder. Physicians must pay special attention to the possible presence of subclinical hypothyroidism when administering statins in patients with hypercholesterolemia.

Comparative Antitumor Activity of Different Solvent Fractions from an Auricularia auricula-judae Ethanol Extract in P388D1 and Sarcoma 180 Cells

The objective of this study was to evaluate and compare the antitumor activity of different solvent fractions (ethanol, dichloromethane, ethyl acetate, butanol and water) of the Auricularia auricula-judae 70% ethanol extract on the P388D1 macrophage and sarcoma 180 cells. A dose-dependent antitumor activity of each solvent fraction (from 0.01 mg/ml to 0.3 mg/ml) was shown against both cell types. These cytotoxic effects of all the tested fractions were confirmed on the MTT and SRB assays, without statistical differences each other. IC₅₀ value of dichloromethane fraction was 94.2 μg/ml against sarcoma 180 cells lower than any other solvent fractions. The potent antitumor effect of the dichloromethane (DCM) fraction was also found against solid tumor in BALB/c mice. The splenomegaly and higher splenic index were found in tumor-bearing mice, with the DCM fraction returning to the negative control values. Thus, the results indicated the dichloromethane fraction may have potential ingredients as antitumor candidates.

Serum IgA reactivity against GroEL of Streptococcus sanguinis and human heterogeneous nuclear ribonucleoprotein A2/B1 in patients with Behçet disease

BACKGROUND

Infectious agents, especially Streptococcus sanguinis and herpes simplex virus, have long been postulated as major triggering factors for Behçet disease (BD).

OBJECTIVES

To identify an anti-S. sanguinis antigen reacting with serum IgA antibody in patients with BD.

METHODS

We detected a target protein by proteomics analysis and evaluated serum IgA reactivity of 100 patients with BD against the identified streptococcal target protein and human heterogeneous nuclear ribonucleoprotein (hnRNP) A2/B1. Homologous epitope sequences between the streptococcal target protein and human hnRNP A2/B1 were also evaluated.

RESULTS

Four protein bands were detected by immunoprecipitation, and chaperonin GroEL was identified by a proteomics analysis. Reactivity of serum IgA against recombinant S. sanguinis GroEL was detected in 77 of 100 patients with BD (77%) and in 21 of 70 healthy controls (30%). In addition, reactivity of serum IgA against human recombinant hnRNP A2/B1 was seen in 79 of 100 patients with BD (79%) and in eight of 70 healthy controls (11%). Among the eight distinctive epitopes with significant homology between S. sanguinis GroEL and human hnRNP A2/B1, the serum IgA reactivity of patients with BD was markedly higher with epitope 3 (hnRNP A2/B1 peptide 33-46 and GroEL peptide 57-70) and epitope 6 (hnRNP A2/B1 peptide 177-188 and GroEL peptide 347-358).

CONCLUSION

We identified an S. sanguinis GroEL protein as a target of serum anti-S. sanguinis IgA antibody reactivity in patients with BD. In addition, patients with BD exhibited serum IgA reactivity against homologous epitope regions between S. sanguinis GroEL and human hnRNP A2/B1.

RAF kinase inhibitor-independent constitutive activation of Yes-associated protein 1 promotes tumor progression in thyroid cancer

The transcription coactivator Yes-associated protein 1 (YAP1) is regulated by the Hippo tumor suppressor pathway. However, the role of YAP1 in thyroid cancer, which is frequently associated with the BRAF^V600E mutation, remains unknown. This study aimed to investigate the role of YAP1 in thyroid cancer. YAP1 was overexpressed in papillary (PTC) and anaplastic thyroid cancer, and nuclear YAP1 was more frequently detected in BRAF^V600E (+) PTC. In the thyroid cancer cell lines TPC-1 and HTH7, which do not have the BRAF^V600E mutation, YAP1 was cytosolic and inactive at high cell densities. In contrast, YAP1 was retained in the nucleus and its target genes were expressed in the thyroid cancer cells 8505C and K1, which harbor the BRAF^V600E mutation, regardless of cell density. Furthermore, the nuclear activation of YAP1 in 8505C was not inhibited by RAF or MEK inhibitor. In vitro experiments, YAP1 silencing or overexpression affected migratory capacities of 8505C and TPC-1 cells. YAP1 knockdown resulted in marked decrease of tumor volume, invasion and distant metastasis in orthotopic tumor xenograft mouse models using the 8505C thyroid cancer cell line. Taken together, YAP1 is involved in the tumor progression of thyroid cancer and YAP1-mediated effects might not be affected by the currently used RAF kinase inhibitors.

Both the sera of patients with Behçet's disease and Streptococcus sanguis stimulate membrane expression of hnRNP A2/B1 in endothelial cells

OBJECTIVES

Heterogeneous nuclear ribonucleoprotein (hnRNP) A2/B1 has been identified as a target antigen of anti-endothelial cell immunglobulin (Ig)A antibodies in patients with Behçet's disease (BD). The aim was to investigate the effects of the sera from BD patients and Streptococcus sanguis on the subcellular expression of hnRNP A2/B1 in human dermal microvascular endothelial cells (HDMECs).

METHOD

The sera of BD patients and healthy controls (HC) as well as cultured S. sanguis were used to stimulate HDMECs. Subcellular fractions were obtained from stimulated HDMECs and were subjected to immunoblot analyses. The distribution of hnRNP A2/B1 was investigated by immunocytochemistry and direct immunofluorescence study was performed in biopsy specimens of mucosal ulcers from BD patients.

RESULTS

BD patients' sera increased the membrane expression of hnRNP A2/B1 in HDMECs after 12 and 24 h of incubation compared with HDMECs incubated with endothelial cell culture media and HC sera. S. sanguis also increased hnRNP A2/B1 in the cellular membrane. hnRNP A2/B1 mRNA level was also significantly upregulated in HDMECs incubated with BD patients' sera and S. sanguis. Immunocytochemistry demonstrated marked expression of hnRNP A2/B1 in the cytoplasm and cellular membrane of HDMECs incubated with BD patients' sera or S. sanguis. In addition, direct immunofluorescence experiments revealed the co-localization of serum IgA antibodies and monoclonal antibodies (mAbs) against hnRNP A2/B1 in tissue sections from ulcers of BD patients.

CONCLUSIONS

Our data indicate that both the sera of BD patients with active disease and S. sanguis infection are inflammatory stimuli that can induce membranous hnRNP A2/B1 expression in HDMECs.

Distinct groups and antimicrobial resistance of clinical Stenotrophomonas maltophilia complex isolates from Korea

One hundred and twenty-one isolates of Stenotrophomonas maltophilia complex were collected from seven Korean hospitals. Species and groups were identified using partial gyrB gene sequences and antimicrobial susceptibility testing was performed using a broth microdilution method. Based on partial gyrB gene sequences, 118 isolates were identified as belonging to S. maltophilia complex, including S. maltophilia, S. pavanii, Pseudomonas beteli, P. geniculata and P. hibisciola. The S. maltophilia isolates were further divided into three groups, I to III. S. maltophilia groups II and III were clustered into clade A with S. pavanii and P. beteli; S. maltophilia group I was clustered into clade B with P. geniculata and P. hibisciola. For all S. maltophilia complex isolates, the resistance rate to trimethoprim/sulfamethoxazole (TMP/SMX) was very high (30.5%). Antimicrobial resistance rates varied among species or groups of S. maltophilia complex. Isolates of clade A showed significantly lower antimicrobial resistance rates than those of clade B; while 25% of clade A isolates were multidrug resistant, 46% of clade B isolates were multidrug resistant (P=0.001). The finding of high antimicrobial resistance rates, particularly to TMP/SMX, among S. maltophilia complex isolates from Korea, and the existence of distinct groups among the isolates, with differences in antimicrobial resistance rates, suggests consideration of alternative agents to TMP/SMX to treat S. maltophilia infections and indicates the importance of accurate identification for appropriate selection of treatment options.

Appearance and dynamics of helical flux tubes under electron cyclotron resonance heating in the core of KSTAR plasmas

Dual (or sometimes multiple) flux tubes (DFTs) have been observed in the core of sawtoothing KSTAR tokamak plasmas with electron cyclotron resonance heating. The time evolution of the flux tubes visualized by a 2D electron cyclotron emission imaging diagnostic typically consists of four distinctive phases: (1) growth of one flux tube out of multiple small flux tubes during the initial buildup period following a sawtooth crash, resulting in a single dominant flux tube along the m/n=1/1 helical magnetic field lines, (2) sudden rapid growth of another flux tube via a fast heat transfer from the first one, resulting in approximately identical DFTs, (3) coalescence of the two flux tubes into a single m/n=1/1 flux tube resembling the internal kink mode in the normal sawteeth, which is explained by a model of two current-carrying wires confined on a flux surface, and (4) fast localized crash of the merged flux tube similar to the standard sawtooth crash. The dynamics of the DFTs implies that the internal kink mode is not a unique prerequisite to the sawtooth crash, providing a new insight on the control of the sawtooth.

The optimization of ELISA for methamphetamine determination: the effect of immunogen, tracer and antibody purification method on the sensitivity

To obtain more sensitive immunoassay for methamphetamine (MA) determination, the optimum condition of enzyme-linked immunosorbent assay (ELISA) was investigated in regard to immunogens, antibody purification methods and coating tracers. Activated MA, N-(4-aminobutyl)methamphetamine (4-ABMA), was conjugated with bovine serum albumin (BSA) or keyhole limpet hemocyanin (KLH) and used as immunogen. The antibodies were purified by protein G chromatography or various immunoaffinity chromatography-linked MA-protein ligands, such as MA-BSA, MA-KLH or MA-ovalbumin (OVA). Each purified antibody was characterized by means of sensitivity and cross-reactivity using the three MA-protein coating tracers, MA-BSA, MA-KLH and MA-OVA. The best sensitivity of each antibody was acquired with the MA-OVA tracer although the tracer concentration and the antibody titer level at optimum condition were varied. The antibody with high titer level did not always yield good sensitivity. At optimum condition, immunoaffinity chromatography-purified antibodies were better for sensitivity and for specificity than protein G-purified antibodies. The cross-reactivity of the purified antibodies seemed to be affected by immunogen structure and showed somewhat different patterns according to the immunoaffinity ligand utilized. These data show that the antibody purification method as well as choice of coating tracer and immunogen is essential for the sensitivity and specificity of EIA; the optimum condition for assay should be discovered using various methods and combinations.

Behçet's disease in concurrence with psoriasis

BACKGROUND

Behçet's disease (BD) and psoriasis are chronic inflammatory diseases characterized by multisystemic vasculitis and epidermal hyperplasia respectively. Although it has been found that the pathogenesis of BD and psoriasis share common perspectives, reports of patients who have both diseases in concurrence are rare.

OBJECTIVES

To analyse and evaluate the clinical manifestations of BD patients who have psoriasis together.

METHODS

Retrospective evaluation of the medical records of nine BD patients who were also diagnosed with psoriasis at the BD Specialty Clinic of Severance Hospital was carried out. We analysed the characteristics of patients and the clinical activity of both diseases, and also the effect of the treatment of one disease against the other.

RESULTS

Of the nine BD patients who also had psoriasis, male to female ratio was 1 : 2. Two (22.2%) patients had a complete type of BD and seven (77.8%) patients had an incomplete type of BD. For the psoriatic lesions, all nine (100%) patients were diagnosed as psoriasis vulgaris. Five (55.6%) patients had BD as the preceding disease and four (44.4%) patients had psoriasis as the preceding. All five patients who formerly developed BD followed by psoriasis had an active state of BD, but the activity of psoriasis of all nine patients was minimal to average.

CONCLUSION

In this study, we evaluated the clinical manifestations of nine patients who had BD and psoriasis together. Although the exact pathogenesis remains unclear, there might be some influence by each disease to the other between BD and psoriasis.

Replicon sequence typing of IncF plasmids and the genetic environments of blaCTX-M-15 indicate multiple acquisitions of blaCTX-M-15 in Escherichia coli and Klebsiella pneumoniae isolates from South Korea

OBJECTIVES

The purpose of this study was to investigate variations in IncF plasmids and the genetic environments of bla(CTX-M-15) in CTX-M-15-producing Escherichia coli and Klebsiella pneumoniae isolates from South Korea.

METHODS

A total of 56 E. coli and 15 K. pneumoniae isolates, which were previously characterized for CTX-M-15 production, sequence type by multilocus sequence typing and replicon type, were included in this study. Replicon sequence typing for IncF plasmids was performed and the genetic environments of bla(CTX-M-15) were determined using PCR and sequencing.

RESULTS

A total of 34 and 10 IncF-replicon sequence types (RSTs) were identified among the E. coli and K. pneumoniae isolates, respectively. Only eight and four IncF-RSTs were found in multiple isolates of E. coli and K. pneumoniae, respectively. No common IncF-RSTs were found between E. coli and K. pneumoniae isolates. Five and three different bla(CTX-M-15) genetic environments were identified in E. coli and K. pneumoniae isolates, respectively. Even in the same E. coli clone, diverse IncF-RSTs and bla(CTX-M-15) genetic environments were identified.

CONCLUSIONS

Diverse IncF plasmids have incorporated into diverse strains of E. coli and K. pneumoniae, contributing to the spread of the CTX-M-15 extended-spectrum β-lactamase in South Korea. It can also be inferred that bla(CTX-M-15) has not been transferred directly from E. coli to K. pneumoniae.

Transthoracic needle biopsy using a C-arm cone-beam CT system: diagnostic accuracy and safety

OBJECTIVE

The purpose of this study was to evaluate the diagnostic accuracy and safety of performing transthoracic needle biopsy (TNB) under combined fluoroscopy and CT guidance using a C-arm cone-beam CT (CBCT) system.

METHODS

We evaluated the diagnostic accuracy and safety of performing TNB using a C-arm CBCT system. We retrospectively evaluated 99 TNB cases performed in 98 patients using a C-arm CBCT system with an 18-gauge automated cutting needle. We reviewed the diagnostic accuracy according to the size and depth of the lesion, incidence of complications, additional treatment for complications, procedure time, number of needle passes per biopsy and radiation dose.

RESULTS

The final diagnoses revealed 72 malignant and 27 benign lesions. The overall malignancy sensitivity, malignancy specificity and diagnostic accuracy were 95.8%, 100% and 97.0%, respectively, and those for small pulmonary nodules <20 mm in size were 94.1%, 100% and 96.6%, respectively. There was no significant difference in the correct diagnosis of malignancy according to lesion size (p = 0.634) or depth (p = 0.542). For benign lesions, a specific diagnosis was obtained in 14 cases (51.9%). TNB induced complications in 19 out of 99 procedures (19.2%), including pneumothorax (16.2%), immediate haemoptysis (2.0%) and subcutaneous emphysema (1.0%). Among these, four patients with pneumothorax required chest tube insertion (2.0%) or pig-tail catheter drainage (2.0%). The mean procedure time, number of needle passes and radiation doses were 11.9 ± 4.0 min, 1.2 ± 0.5 times and 170.0 ± 67.2 mGy, respectively.

CONCLUSION

TNB using a C-arm CBCT system provides high diagnostic accuracy with a low complication rate and a short procedure time, particularly for small pulmonary nodules.

Two-dimensional visualization of growth and burst of the edge-localized filaments in KSTAR H-mode plasmas

The filamentary nature and dynamics of edge-localized modes (ELMs) in the KSTAR high-confinement mode plasmas have been visualized in 2D via electron cyclotron emission imaging. The ELM filaments rotating with a net poloidal velocity are observed to evolve in three distinctive stages: initial linear growth, interim quasisteady state, and final crash. The crash is initiated by a narrow fingerlike perturbation growing radially from a poloidally elongated filament. The filament bursts through this finger, leading to fast and collective heat convection from the edge region into the scrape-off layer, i.e., ELM crash.

Brain-derived neurotrophic factor gene polymorphisms and mirtazapine responses in Koreans with major depression

Brain-derived neurotrophic factor (BDNF) is a candidate molecule for influencing the clinical response to antidepressant treatment. The aims of this study were to determine the relationship between the Val66Met polymorphism in the BDNF gene and the response to mirtazapine in 243 Korean subjects with major depressive disorder (MDD). The reduction in the Hamilton Depression score over the 8-week treatment period was not influenced by BDNF V66M genotypes. A marginal effect of genotype on somatic anxiety score was observed at baseline (P = 0.047 in the dominant model). However, genotype-time interaction had no effect on somatic anxiety score after the 8-week a treatment period. Plasma BDNF levels tended to increase during mirtazapine treatment, although without statistical significance (P = 0.055). After 8 weeks of mirtazapine treatment, plasma BDNF levels were higher in Met allele homozygotes (1499.7 ± 370.6 ng/mL) than in Val allele carriers (649.7 ± 158.5 ng/mL, P = 0.049). Our results do not support the hypothesis that the Val66Met promoter polymorphism in the BDNF gene influences the therapeutic response to mirtazapine in Korean MDD patients. However, our data indicate that this polymorphism results in increased plasma BDNF after mirtazapine treatment.

Relatively scaled ECE temperature profiles of KSTAR plasmas

A scheme to obtain relatively scaled profiles of electron cyclotron emission (ECE) temperature directly from uncalibrated raw radiometer data is proposed and has been tested for the 2009 campaign KSTAR plasmas. The proposed method utilizes a position controlled system to move the plasma adiabatically and compares ECE radiometer channels at the same relative radial positions assuming the profile consistency during the adiabatic change. This scaling method is an alternative solution when an absolute calibration is unreliable or too time consuming. The application to the two dimensional ECE imaging data, wherein calibration is extremely difficult, may also prove to be useful.

Development of KSTAR ECE imaging system for measurement of temperature fluctuations and edge density fluctuations

The ECE imaging (ECEI) diagnostic tested on the TEXTOR tokamak revealed the sawtooth reconnection physics in unprecedented detail, including the first observation of high-field-side crash and collective heat transport [H. K. Park, N. C. Luhmann, Jr., A. J. H. Donné et al., Phys. Rev. Lett. 96, 195003 (2006)]. An improved ECEI system capable of visualizing both high- and low-field sides simultaneously with considerably better spatial coverage has been developed for the KSTAR tokamak in order to capture the full picture of core MHD dynamics. Direct 2D imaging of other MHD phenomena such as tearing modes, edge localized modes, and even Alfvén eigenmodes is expected to be feasible. Use of ECE images of the optically thin edge region to recover 2D electron density changes during L/H mode transitions is also envisioned, providing powerful information about the underlying physics. The influence of density fluctuations on optically thin ECE is discussed.

Immunomodulatory activities and subacute toxicity of a novel β-glucan from Paenibacillus polymyxa JB115 in rats

Subacute toxicity and immunopharmacological activities of β-glucan from P. polymyxa JB115 was evaluated in a 28-day feeding study in rats. The white blood cell count, red blood cell count, hematocrit, hemoglobin, thrombocytes (THR) and thrombocytocrit were significantly higher in male fed with β-glucan than control rats and the insignificant lower eosinophil count, mean corpuscular volume, mean cell hemoglobin and uninfected THR (uTHR) levels were observed in male whereas no marked changes in female rats. No other significant differences in serum chemistry and liver, kidney, and spleen weights were observed. The pathological changes and other abnormal indicators were not detected in urine. Female rats fed with diet supplemented with 0.01% β-glucan also showed marked increase in the percentage of blood cytotoxic T-lymphocytes compared to that of the control group while not significant differences in the percentage of blood B-lymphocytes. No adverse effects on general condition and behavior, growth, feed and water consumption and feed conversion efficiency were found. The results suggest that consumption of the novel β-1, 3/1, 6-glucan from P. polymyxa JB115 was not associated with any obvious toxic effects in rats, indicating its safety as a potential immunostimulant or as an adjuvant of some animal vaccines.

Elastic vesicles as topical/transdermal drug delivery systems

Skin acts a major target as well as a principle barrier for topical/transdermal drug delivery. Despite the many advantages of this system, the major obstacle is the low diffusion rate of drugs across the stratum corneum. Several methods have been assessed to increase the permeation rate of drugs temporarily. One simple and convenient approach is application of drugs in formulation with elastic vesicles or skin enhancers. Elastic vesicles are classified with phospholipid (Transfersomes((R)) and ethosomes) and detergent-based types. Elastic vesicles were more efficient at delivering a low and high molecular weight drug to the skin in terms of quantity and depth. Their effectiveness strongly depends on their physicochemical properties: composition, duration and application volume, and entrapment efficiency and application methods. This review focuses on the effect of elastic liposomes for enhancing the drug penetration and defines the action mechanism of penetration into deeper skin.

Studies on the Dermal and Ocular Irritation of Prodigiosin Isolated from Zooshikella rubidus

This study was carried out to investigate the irritation of the prodigiosin isolated from Zooshikella rubidus on the skin and eyes in New Zealand white rabbits. The tests were performed on the basis of Korea Food and Drug Administration (KFDA) guidelines. Prodigiosin induced severe eye irritation at high concentration (0.5 g/site/ml) but there was no eye irritation at low concentration (0.3 mg/site/ ml). The primary irritation index was calculated from higher concentration (0.5 g/site/ml) to lower concentration (0.3 mg/site/ml). There were found non-irritation or induced mild irritation at lower concentration of prodigiosin application. On the basis of this study, it could be concluded that the prodigiosin may be non-irritant to mild irritant of usual application at lower concentration (0.3 mg/site) resulting it is safe and useful in dyeing technology of fabrics.

Mycoplasma hyopneumoniae Induces Grap, Gadd45β, and secreted phosphoprotein 1 Gene Expression as Part of the Inflammatory Response in RAW264.7 Cells

Genes related to Mycoplasma hyopneumoniae-induced inflammation were identified using the gene-fishing technology, an improved method for identifying differentially expressed genes (DEGs) using an annealing control primer (ACP) system in RAW264.7 cells. After treatment with M. hyopneumo-niae, 16 DEGs were expressed in RAW264.7 cells using a pre-screening system. Among these 16 DEGs, 11 DEGs (DEGs 1, 4, 5-10, 12-15) were selected and sequenced directly, revealing that DEG12 (Grap), DEG14 (Gadd45), and DEG15 (secreted phosphoprotein 1) were related to inflammatory cytokines. This is the first report that intact M. hyopneumoniae induces the expression of Grap, Gadd 45β, and secreted phosphoprotein 1 in RAW264.7 cells. Subsequently, these genes may be targets for screening novel inhibitors of the mycoplasmal inflammatory response.

Effects of low-intensity ultrasound (LIUS) stimulation on human cartilage explants

OBJECTIVE

To evaluate the effects of low-intensity ultrasound (LIUS) stimulation on the anabolic state of human cartilage from patients with osteoarthritis (OA).

METHODS

Explant cultures of human OA cartilage were stimulated for 10 min every day for 7 consecutive days using continuous-wave sonication at a frequency of 1 MHz with spatial and temporal average intensities of 0 (control), 40, 200, 500, or 700 mW/cm2. The effects of LIUS on cell proliferation were evaluated by 3H-thymidine incorporation. Proteoglycan synthesis was evaluated by the incorporation of 35S-sulfate and by Safaranin O staining. Collagen synthesis was evaluated by 3H-proline incorporation and immunohistochemistry.

RESULTS

At an intensity of 200 mW/cm2, LIUS treatment induced the expression of collagen type II and proteoglycan measured by the incorporation of radioactivity and specific staining of the cartilage explants. However, the expression decreased again at the higher intensities of 500 or 700 mW/cm2. Ultrasound had no stimulatory effect on cell proliferation at any intensity.

CONCLUSION

LIUS has anabolic effects on human cartilage in explant cultures, indicating a potentially important method for the repair of osteoarthritic cartilage.

Evaluation of the Antioxidant Capacity and Preventive Effects of a Topical Emulsion and Its Vehicle Control on the Skin Response to UV Exposure

Supplying topical exogenous antioxidants to the skin may prevent or minimize free radical-induced damaging. This study determines antioxidative capacity of a topical skin care emulsion (an oil-in-water vitamin E-containing formulation) versus its vehicle on human skin that was exposed to ultraviolet radiation (UVR) by utilizing a photochemiluminescence device and biophysical methods. Ten healthy Caucasians (3 male and 7 female; mean age 47 +/- 10 years) were enrolled. In a randomized and double-blind manner, a pH-balanced vitamin E emulsion or its vehicle control was applied onto predesignated forearm prior to UVR exposure. Thirty minutes after application, these test sites were exposed to a UV light to induce the minimal erythema dose. One untreated site served as a blank control. Visual scoring and instrumental measurements were recorded at baseline and at 24 h and 48 h thereafter. At day 3, after completing instrumental measurements, each test site was stripped three times in a consecutive manner with a proprietary adhesive tape disc. These tapes were quantified for antioxidant capacity using a photochemiluminescence device. Vitamin E emulsion and vehicle control significantly (p < 0.05) suppressed visual scores when compared with blank control at day 2 and day 3 after UV exposure. However, vitamin E emulsion showed significantly (p < 0.05) lower visual scores when compared with vehicle control at day 2 and day 3 after UV exposure.Also,vitamin E emulsion and its vehicle control significantly (p < 0.05) diminished skin color measurement (a*) values when compared with blank control at day 2 and day 3 after UV exposure. At day 2 after UV exposure, only vitamin E emulsion significantly (p < 0.05) reduced skin blood flow volume when compared with blank control. Vitamin E emulsion and its vehicle control showed significant (p < 0.05) reduction of blood flow volume when compared with blank control at day 3 after UV exposure. Vitamin E emulsion and its vehicle control proved effective in preventing induction of erythema and reducing inflammatory damage caused by UV exposure. The effect of vitamin E emulsion exceeded that of an 'active control'.

Liposomes and niosomes as topical drug delivery systems

The skin acts as a major target as well as a principle barrier for topical/transdermal (TT) drug delivery. The stratum corneum plays a crucial role in barrier function for TT drug delivery. Despite major research and development efforts in TT systems and the advantages of these routes, low stratum corneum permeability limits the usefulness of topical drug delivery. To overcome this, methods have been assessed to increase permeation. One controversial method is the use of vesicular systems, such as liposomes and niosomes, whose effectiveness depends on their physicochemical properties. This review focuses on the effect of liposomes and niosomes on enhancing drug penetration, and defines the effect of composition, size and type of the vesicular system on TT delivery.

Serotonergic genes and personality traits in the Korean population

Serotonergic genes have been implicated in mood disorders, alcoholism and certain personality traits. The goal of this study was to investigate the relationship between personality traits and several important genes in the serotonin system. The participants included 146 healthy adults with no history of psychiatric disorders or other physical illness during the last 6 months. All participants were tested by the Temperament and Character Inventory (TCI) and genotyped serotonin transporter, serotonin receptors (5-HT(2A) and 5-HT(6)) and tryptophan hydroxylase gene polymorphisms. Genotyping was analyzed with polymerase chain reaction. Differences in TCI dimensions and sub-scales among three groups were examined with ANOVA. Our result suggested that 5-HT(2A) receptor gene polymorphism (A-1438G) appears to be associated with self-determinism and self-transcendence (ST). Our result also indicated a significant relationship between 5-HT(6) receptor gene polymorphism (C267T) and ST. Further studies of polymorphisms of other genes and their interactions may clarify the complex relationship between personality and genes.

Topical vaccination of DNA antigens: topical delivery of DNA antigens

Topical DNA vaccines have been shown to elicit both broad humoral and cellular immune responses in vivo. The skin is an attractive site for the delivery of DNA antigens for DNA vaccination. However, due to skin's barrier properties, the penetration of DNA and the applications of topical vaccination are limited. To improve permeability, chemical and physical approaches have been examined to decrease stratum corneum barrier properties. Topical vaccination has been achieved using topical application of naked DNA, DNA/liposomes or emulsion complex, liposomal cream, as well as physical methods such as stripping, electroporation, and micromechanical disruption methods. All methods resulted in a significant enhancement in humoral and cellular immune responses over naked DNA alone. To develop more cost-effective and needle-free vaccines, skin-targeted immunizations are required. This review focuses on the chemical and physical methods developed to enhance DNA delivery into skin.