Ga-Doped Pt-Ni Octahedral Nanoparticles as a Highly Active and Durable Electrocatalyst for Oxygen Reduction Reaction

Bimetallic PtNi nanoparticles have been considered as a promising electrocatalyst for oxygen reduction reaction (ORR) in polymer electrolyte membrane fuel cells (PEMFCs) owing to their high catalytic activity. However, under typical fuel cell operating conditions, Ni atoms easily dissolve into the electrolyte, resulting in degradation of the catalyst and the membrane-electrode assembly (MEA). Here, we report gallium-doped PtNi octahedral nanoparticles on a carbon support (Ga-PtNi/C). The Ga-PtNi/C shows high ORR activity, marking an 11.7-fold improvement in the mass activity (1.24 A mg_Pt^-1) and a 17.3-fold improvement in the specific activity (2.53 mA cm^-2) compared to the commercial Pt/C (0.106 A mg_Pt^-1 and 0.146 mA cm^-2). Density functional theory calculations demonstrate that addition of Ga to octahedral PtNi can cause an increase in the oxygen intermediate binding energy, leading to the enhanced catalytic activity toward ORR. In a voltage-cycling test, the Ga-PtNi/C exhibits superior stability to PtNi/C and the commercial Pt/C, maintaining the initial Ni concentration and octahedral shape of the nanoparticles. Single cell using the Ga-PtNi/C exhibits higher initial performance and durability than those using the PtNi/C and the commercial Pt/C. The majority of the Ga-PtNi nanoparticles well maintain the octahedral shape without agglomeration after the single cell durability test (30,000 cycles). This work demonstrates that the octahedral Ga-PtNi/C can be utilized as a highly active and durable ORR catalyst in practical fuel cell applications.

Low serum phosphate as an independent predictor of increased infection-related mortality in dialysis patients: A prospective multicenter cohort study

BACKGROUND

The role of mineral metabolism in mortality among dialysis patients has received increased attention, but some aspects remain unclear. The aim of the present study was to investigate the prognostic value of serum calcium and phosphate levels for all-cause mortality and cause-specific mortality in dialysis patients.

METHODS

Patients on hemodialysis and peritoneal dialysis were enrolled from a multicenter prospective cohort study in Korea (NCT00931970). The patients were divided into low, normal, and high groups according to their baseline serum calcium or phosphate levels. Cox proportional analysis and a proportional hazards model for the subdistribution of a competing risk were used to calculate hazard ratios (HRs) for the association of serum calcium and phosphate levels with all-cause and cause-specific mortality. Time-dependent values of calcium and phosphate were also evaluated to assess the effect of longitudinal change in mineral metabolism parameters on mortality types.

RESULTS

A total of 3,226 dialysis patients were followed up for a mean of 19.8 ± 8.2 months. Infection was the most common cause of death. Low serum phosphate was significantly associated with all-cause and infection-related death using time-dependent values (HR, 1.43 [95% confidence interval (CI), 1.06-1.93], P = 0.02, and HR, 1.66 [95% CI, 1.02-2.70], P = 0.04, respectively). Low serum phosphate was associated with significantly higher infection-related mortality, especially in patients older than 65 years or on dialysis more than one year or with serum albumin lower than 3.9 g/dL (HR, 2.06 [95% CI, 1.13-3.75], P = 0.02, HR, 2.19 [95% CI, 1.20-4.01], P = 0.01, and HR, 1.77 [95% CI, 1.00-3.13], P = 0.05, respectively). Multinomial logistic regression analysis results suggested that low serum albumin, creatinine, and body mass index correlated with low serum phosphate.

CONCLUSIONS

Low serum phosphate in dialysis patients was an independent risk factor for infection-related death, especially in elderly patients. Persistently low serum phosphate might be a nutritional biomarker to predict increased susceptibility to infection and in turn worse outcomes in dialysis patients.

Synthesis of Chemically Ordered Pt3Fe/C Intermetallic Electrocatalysts for Oxygen Reduction Reaction with Enhanced Activity and Durability via a Removable Carbon Coating

Recently, Pt₃M (M = Fe, Ni, Co, Cu, etc.) intermetallic compounds have been highlighted as promising candidates for oxygen reduction reaction (ORR) catalysts. In general, to form those intermetallic compounds, alloy phase nanoparticles are synthesized and then heat-treated at a high temperature. However, nanoparticles easily agglomerate during the heat treatment, resulting in a decrease in electrochemical surface area (ECSA). In this study, we synthesized Pt-Fe alloy nanoparticles and employed carbon coating to protect the nanoparticles from agglomeration during heat treatment. As a result, Pt₃Fe L1₂ structure was obtained without agglomeration of the nanoparticles; the ECSA of Pt-Fe alloy and intermetallic Pt₃Fe/C was 37.6 and 33.3 m² g_Pt^-1, respectively. Pt₃Fe/C exhibited excellent mass activity (0.454 A mg_Pt^-1) and stability with superior resistances to nanoparticle agglomeration and iron leaching. Density functional theory (DFT) calculation revealed that, owing to the higher dissolution potential of Fe atoms on the Pt₃Fe surface than those on the Pt-Fe alloy, Pt₃Fe/C had better stability than Pt-Fe/C. A single cell fabricated with Pt₃Fe/C showed higher initial performance and superior durability, compared to that with commercial Pt/C. We suggest that Pt₃M chemically ordered electrocatalysts are excellent candidates that may become the most active and durable ORR catalysts available.

Impact of dialysis modality on technique survival in end-stage renal disease patients

BACKGROUND/AIMS

This study analyzed the risk factors for technique survival in dialysis patients and compared technique survival rates between hemodialysis (HD) and peritoneal dialysis (PD) in a prospective cohort of Korean patients.

METHODS

A total of 1,042 patients undergoing dialysis from September 2008 to June 2011 were analyzed. The dialysis modality was defined as that used 90 days after commencing dialysis. Technique survival was compared between the two dialysis modalities, and the predictive risk factors were evaluated.

RESULTS

The dialysis modality was an independent risk factor predictive of technique survival. PD had a higher risk for technique failure than HD (hazard ratio [HR], 10.8; 95% confidence interval [CI], 1.9 to 62.0; p = 0.008) during a median follow-up of 11.0 months. In the PD group, a high body mass index (BMI) was an independent risk factor for technique failure (HR, 1.3; 95% CI, 1.0 to 1.8; p = 0.036). Peritonitis was the most common cause of PD technique failure. The difference in technique survival between PD and HD was more prominent in diabetic patients with a good nutritional status and in non-diabetic patients with a poor nutritional status.

CONCLUSIONS

In a prospective cohort of Korean patients with end-stage renal disease, PD was associated with a higher risk of technique failure than HD. Diabetic patients with a good nutritional status and non-diabetic patients with a poor nutritional status, as well as patients with a higher BMI, had an inferior technique survival rate with PD compared to HD.

Optimal assessment of lymph node status in gallbladder cancer

BACKGROUND

Lymph node (LN) metastasis is an important prognostic factor in gallbladder cancer (GBCA). LN status has been adopted as a critical element of staging systems. However, the influence of total lymph node count (TLNC) remains unclear. We determined the optimal minimum TLNC and compared the prognostic significance of LN status indices in GBCA.

METHODS

We retrospectively reviewed medical records of 128 patients with T2 or greater GBCA who underwent LN dissection. We analyzed overall survival (OS) and relevance of the number of metastatic LNs, ratio of metastatic LNs to retrieved LNs (LNR), and TLNC in predicting OS.

RESULTS

The median OS durations were 120, 35, and 18 months in T2, T3, and T4 GBCA. Five-year OS rates were 73%, 43%, and 0% in T2, T3, and T4 GBCA. LN status did not significantly impact OS in T2 or T4 GBCA. However, all LN indices were significantly correlated with OS in T3 GBCA. Furthermore, multivariate analysis revealed that a metastatic LN count of more than four and a TLNC of more than eight were independent prognostic factors of OS in T3 GBCA.

CONCLUSIONS

TLNC and the number of positive LNs may be more important prognostic factors than LNR in T3 GBCA. Additionally, accurate staging may not be achieved in cases of T3 GBCA if the total number of retrieved LNs is less than eight. Thus, to ensure proper staging, we recommend that surgeons harvest more than eight LNs in patients with T3 GBCA.

Deacetylation of the tumor suppressor protein PML regulates hydrogen peroxide-induced cell death

The promyelocytic leukemia protein (PML) is a tumor suppressor that is expressed at a low level in various cancers. Although post-translational modifications including SUMOylation, phosphorylation, and ubiquitination have been found to regulate the stability or activity of PML, little is known about the role of its acetylation in the control of cell survival. Here we demonstrate that acetylation of lysine 487 (K487) and SUMO1 conjugation of K490 at PML protein are mutually exclusive. We found that hydrogen peroxide (H₂O₂) promotes PML deacetylation and identified SIRT1 and SIRT5 as PML deacetylases. Both SIRT1 and SIRT5 are required for H₂O₂-mediated deacetylation of PML and accumulation of nuclear PML protein in HeLa cells. Knockdown of SIRT1 reduces the number of H₂O₂-induced PML-nuclear bodies (NBs) and increases the survival of HeLa cells. Ectopic expression of wild-type PML but not the K487R mutant rescues H₂O₂-induced cell death in SIRT1 knockdown cells. Furthermore, ectopic expression of wild-type SIRT5 but not a catalytic defective mutant can also restore H₂O₂-induced cell death in SIRT1 knockdown cells. Taken together, our findings reveal a novel regulatory mechanism in which SIRT1/SIRT5-mediated PML deacetylation plays a role in the regulation of cancer cell survival.

Successful treatment of recurrent focal segmental glomerulosclerosis with a low dose rituximab in a kidney transplant recipient

Recurrence of focal segmental glomerulosclerosis (FSGS) is a major therapeutic challenge in kidney transplantation (KT). Although intensive plasmapheresis and high-dose rituximab have been introduced to treat recurrent FSGS, the most effective dosage and regimen of rituximab have not been determined. Herein we reported the first case of successful treatment of recurrent FSGS with a low-dose rituximab. The patient showed marked proteinuria (3.5 g/d) and oliguria 2 d after KT. Two courses of plasmapheresis and immunoglobulin were applied to the patient, however, nephrotic range proteinuria persisted and creatinine level increased to 3.56 mg/dL. Five months post-transplant, the patient received injection with only one dose of rituximab 100 mg, without further plasmapheresis, which resulted in immediate reduction of serum creatinine and full remission of proteinuria during the following 18 months. This case suggested that recurrent FSGS, which frequently relapses after plasmapheresis, could be treated successfully with a low-dose rituximab even without plasmapheresis.

Abstract P4-12-28: HER2-related biomarkers in HER2+ breast cancer patients in Asia Pacific

Recent findings suggest that HER2-related molecular markers such as PTEN deletion or downregulation, PIK3CA mutation, truncated HER2 receptor (p95HER2), and tumor HER2 mRNA levels, have the potential to predict anti-HER2 treatment response. We evaluated the distribution of these biomarkers at the time of primary diagnosis and their relationship to responsiveness to lapatinib treatment in the metastatic setting in HER2+ breast cancer patients.

We conducted an observational study of female HER2+ breast cancer patients who were initiated on lapatinib treatment following recurrence or metastases in five Asia Pacific countries. Patients were enrolled between August 2010 and December 2012. Eligible patients had a tumor biopsy specimen available from their primary breast cancer diagnosis or before they started on any anti-HER2 treatment, had not been exposed to more than two lines of anti-HER2 treatment in the metastatic setting or other experimental anti-HER2 treatment, and had no other primary tumor. Biomarkers levels at primary diagnosis were measured; PTEN levels were assessed by immunohistochemistry and PIK3CA mutations were detected by a mass spectroscopy-based approach. The primary endpoint was progression-free survival (PFS) from the initiation of first lapatinib-based regimen given in metastatic setting to disease progression from that regimen or death from any cause. PFS analysis was conducted with a data cut-off date of 31 December 2012.

A total of 162 patients were included in this study and 96% have confirmed HER2+ breast cancer primary tumor. The mean age was 52±10 years and 97% had metastases at study entry, with bone being the most common site of metastasis (48%). About a quarter had PTEN protein loss (24%), 30% had PIK3CA mutation, and 7% had both at primary diagnosis. No significant association was observed between both biomarkers or between each biomarker and estrogen receptor status or HER2 status.

Table 1. Relationship between PTEN and PIK3CA PIK3CA mutation, n (%)PIK3CA wild-type, n (%)p-valuePTEN status  0.674Loss11 (29)27 (71) Normal33 (33)68 (67) 

Patients with altered PTEN expression, or PIK3CA mutation showed comparable PFS with lapatinib-based treatment as those with normal PTEN or PIK3CA expression at analysis cut-off date (median PFS 7.5 and 8.5 months respectively vs. 8.9 and 9.0 months respectively; p = 0.502 and p = 0.268 respectively). There remained no significant difference in PFS after having adjusted for significant confounders (HR 1.2 and 1.1 respectively; 95% CI 0.7–1.9 and 0.7–1.8 respectively; p = 0.481 and p = 0.730 respectively). The distribution of p95HER2 expression and tumor HER mRNA levels and their association with PFS will be included at the time of presentation.

Our preliminary findings suggest that PTEN alteration, or PIK3CA mutation may not be predictive of clinical response to lapatinib treatment in HER2+ breast cancer patients. The final PFS results with additional markers will provide more clues regarding their relationship to treatment response.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-12-28.

Isolation and characterization of a proteinaceous antifungal compound from Lactobacillus plantarum YML007 and its application as a food preservative

Korean kimchi is known for its myriad of lactic acid bacteria (LAB) with diverse bioactive compounds. This study was undertaken to isolate an efficient antifungal LAB strain among the isolated kimchi LABs. One thousand and four hundred LABs isolated from different kimchi samples were initially screened against Aspergillus niger. The strain exhibiting the highest antifungal activity was identified as Lactobacillus plantarum YML007 by 16S rRNA sequencing and biochemical assays using API 50 CHL kit. Lact. plantarum YML007 was further screened against Aspergillus oryzae, Aspergillus flavus, Fusarium oxysporum and other pathogenic bacteria. The morphological changes during the inhibition were assessed by scanning electron microscopy. Preliminary studies on the antifungal compound demonstrated its proteinaceous nature with a molecular weight of 1256·617 Da, analysed by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF). The biopreservative activity of Lact. plantarum YML007 was evaluated using dried soybeans. Spores of A. niger were observed in the negative control after 15 days of incubation. However, fungal growth was not observed in the soybeans treated with fivefold concentrated cell-free supernatant of Lact. plantarum YML007. The broad activity of Lact. plantarum YML007 against various food spoilage moulds and bacteria suggests its scope as a food preservative.

SIGNIFICANCE AND IMPACT OF THE STUDY

After screening 1400 kimchi bacterial isolates, strain Lactobacillus plantarum YML007 was selected with strong antifungal activity against various foodborne pathogens. From the preliminary studies, it was found that the bioactive compound is a low molecular weight novel protein of 1256·617 Da. Biopreservative potential of Lact. plantarum YML007 was demonstrated on soybean grains, and the results point out YML007 as a potent biopreservative having broad antimicrobial activity against various foodborne pathogens.

Clinical characteristics of patients with tuberculosis-destroyed lung

SETTING

Multicentre study.

OBJECTIVE

To define the clinical characteristics of patients with tuberculosis (TB) destroyed lung due to past TB.

DESIGN

We reviewed patients with TB-destroyed lung between May 2005 and June 2011.

RESULTS

A total of 595 patients from 21 hospitals were enrolled. The mean age was 65.63 ± 0.47 (mean ± standard error); 60.5% were male. The mean number of lobes involved was 2.59 ± 0.05. Pleural thickening was observed in 54.1% of the patients. Mean forced vital capacity (FVC), forced expiratory volume in 1 s (FEV(1)), FEV(1)/FVC, bronchodilator response and number of exacerbations per year were respectively 2.06 ± 0.03 l (61.26% ± 0.79), 1.16 ± 0.02 l (49.05% ± 0.84), 58.03% ± 0.70, 5.70% ± 0.34, and 0.40 ± 0.04. The number of lobes involved was significantly correlated with FVC and FEV(1), and with the number of exacerbations per year. Use of long-acting muscarinic antagonists or long-acting beta-2 agonists plus inhaled corticosteroids resulted in bronchodilatory effects. Multivariable regression analysis showed that age, initial FEV(1) (%) and number of exacerbations during follow-up were independent factors affecting change in FEV(1).

CONCLUSION

Decreased lung function with exacerbation, and progressive decline of FEV(1) were observed in patients with TB-destroyed lung.

Early volumetric change and treatment outcome of metastatic brain tumors after external beam radiotherapy: differential radiotherapy for brain metastasis

PURPOSE

To evaluate the treatment outcomes of low-dose whole brain radiation therapy (WBRT)-based differential radiation therapy (RT) for metastatic brain tumors.

METHODS

A total of 242 targets (metastatic brain lesions) were analyzed in the present study. Median WBRT dose and number of fractions were 25 (range 25-35) Gy and 10 (range 8-15) fractions, respectively. A median normalized total dose (NTD) of 1.8 Gy (NTD(1.8Gy)) to the metastatic lesion was 45 (range 27-64.8) Gy. We numbered and contoured each metastatic lesion sequentially using computed tomography fused with serial magnetic resonance imaging to evaluate volumetric changes.

RESULTS

The 6-month and 1-year freedom from remote intracranial failure rates were 87.7 and 58.5 %, respectively. The 6-month actuarial local control (LC) rate was 93.4 %. Tumor diameter was a major determinant for LC, and tumor histology was a significant parameter predicting the volume reduction rate. With overall complete response (CR) rate of 56.6 % after RT, CR rate, if the target was more than 1 cm in size, was 25 % with a median NTD(1.8Gy) of 45 Gy, requiring dose escalation to achieve better target regression.

CONCLUSIONS

Low-dose WBRT with selective boost was feasible and effective. Our results pose the rationale of future trial of differential radiation therapy (RT), which prescribes different radiation dose according to the tumor density in metastatic brain tumors.

Resveratrol prevents renal lipotoxicity and inhibits mesangial cell glucotoxicity in a manner dependent on the AMPK-SIRT1-PGC1α axis in db/db mice

AIMS/HYPOTHESIS

Many of the effects of resveratrol are consistent with the activation of AMP-activated protein kinase (AMPK), silent information regulator T1 (SIRT1) and peroxisome proliferator-activated receptor (PPAR)γ co-activator 1α (PGC-1α), which play key roles in the regulation of lipid and glucose homeostasis, and in the control of oxidative stress. We investigated whether resveratrol has protective effects on the kidney in type 2 diabetes.

METHODS

Four groups of male C57BLKS/J db/m and db/db mice were used in this study. Resveratrol was administered via gavage to diabetic and non-diabetic mice, starting at 8 weeks of age, for 12 weeks.

RESULTS

The db/db mice treated with resveratrol had decreased albuminuria. Resveratrol ameliorated glomerular matrix expansion and inflammation. Resveratrol also lowered the NEFA and triacylglycerol content of the kidney, and this action was related to increases in the phosphorylation of AMPK and the activation of SIRT1-PGC-1α signalling and of the key downstream effectors, the PPARα-oestrogen-related receptor (ERR)-1α-sterol regulatory element-binding protein 1 (SREBP1). Furthermore, resveratrol decreased the activity of phosphatidylinositol-3 kinase (PI3K)-Akt phosphorylation and class O forkhead box (FOXO)3a phosphorylation, which resulted in a decrease in B cell leukaemia/lymphoma 2 (BCL-2)-associated X protein (BAX) and increases in BCL-2, superoxide dismutase (SOD)1 and SOD2 production. Consequently, resveratrol reversed the increase in renal apoptotic cells and oxidative stress, as reflected by renal 8-hydroxy-deoxyguanosine (8-OH-dG), urinary 8-OH-dG and isoprostane concentrations. Resveratrol prevented high-glucose-induced oxidative stress and apoptosis in cultured mesangial cells through the phosphorylation of AMPK and activation of SIRT1-PGC-1α signalling and the downstream effectors, PPARα-ERR-1α-SREBP1.

CONCLUSIONS/INTERPRETATION

The results suggest that resveratrol prevents diabetic nephropathy in db/db mice by the phosphorylation of AMPK and activation of SIRT1-PGC-1α signalling, which appear to prevent lipotoxicity-related apoptosis and oxidative stress in the kidney.

Impact of gene polymorphisms of interleukin-18, transforming growth factor-β, and vascular endothelial growth factor on development of IgA nephropathy and thin glomerular basement membrane disease

Background

We investigated the effects of gene polymorphisms on the development of IgA nephropathy and thin glomerular basement membrane (GBM) disease by analyzing polymorphisms in the interleukin (IL)-18, transforming growth factor (TGF)-β, and vascular endothelial growth factor (VEGF) genes in Korean patients.

Methods

This study included 146 normal individuals and 69 biopsy-proven IgA nephropathy and 44 thin GBM disease patients. The gene polymorphisms −607 A/C and −137 G/C in IL-18, −509C/T and T869C in TGF-β, and −2578C/A and 405C/G in VEGF were investigated in DNA extracted from peripheral blood.

Results

The frequencies of the IL-18 −607CC genotype (43.5% vs. 21.2%, P=0.002, P corrected=0.012) and the VEGF 405 GG genotype (37.7% vs. 21.2%, P=0.002, P corrected=0.012) were significantly increased in the IgA nephropathy group compared with the control group, whereas no significant differences in genotype frequency were observed between the thin GBM disease and control groups. However, there were no significant differences in genotype and allele frequencies between the IgA nephropathy and thin GBM disease groups.

Conclusion

This study did not show any statistically significant differences of six selected gene polymorphisms of the IL-18, TGF-β, and VEGF genes between IgA nephropathy and thin GBM disease. Additional extensive studies are required to clarify the potential role of gene polymorphism to discriminate IgA nephropathy and thin GBM disease without renal biopsy.

Preliminary study for gait phases detection to develop a rehabilitation equipment for hemiplegic patients

Preliminary experiment for analyzing weight shift during gait phases for hemiplegic patients was carried out to develop rehabilitation equipment. A gait phase detection system using pressure sensors was developed and the experiment was carried out for eight hemiplegic patients and normal adult. The weight shift during gait phases for a normal adult showed symmetrical for left and right footing phase, but that for the hemiplegic patients showed asymmetrical footing phase. However, it gave sufficient information to discriminate between left and right footing phases.

A case of transient central diabetes insipidus after aorto-coronary bypass operation

Diabetes insipidus (DI) is characterized by excessive urination and thirst. This disease results from inadequate output of antidiuretic hormone (ADH) from the pituitary gland or the absence of the normal response to ADH in the kidney. We present a case of transient central DI in a patient who underwent a cardiopulmonary bypass (CPB) for coronary artery bypass grafting (CABG). A 44-yr-old male underwent a CABG operation. An hour after the operation, the patient developed polyuria and was diagnosed with central DI. The patient responded to desmopressin and completely recovered five days after surgery. It is probable that transient cerebral ischemia resulted in the dysfunction of osmotic receptors in the hypothalamus or hypothalamus-pituitary axis during CPB. It is also possible that cardiac standstill altered the left atrial non-osmotic receptor function and suppressed ADH release. Therefore, we suggest that central DI is a possible cause of polyuria after CPB.

Hypoxia inducible factor-1α gene polymorphisms in Korean patients with pre-eclampsia

BACKGROUND

Placental hypoxia has been implicated in the pathogenesis of pre-eclampsia. Hypoxia inducible factor-1α (HIF-1α) is activated by low oxygen tension and is a key regulator of genes involved in the cellular responses to hypoxia.

AIM

We determined whether maternal blood c.1722C>T (Pro582Ser) and c.1790G>A (Ala588Thr) polymorphisms in exon 12 of the HIF-1α gene are associated with pre-eclampsia.

SUBJECTS AND METHODS

Subjects included 163 pre-eclamptic patients (48 mild and 115 severe preeclampsia) and 194 healthy pregnant women. Polymorphisms were genotyped by PCR and direct DNA sequencing.

RESULTS

There were no significant differences in genotype or allele frequencies of the c.1772C>T and c.1790G>A polymorphisms of the HIF-1α gene among the study groups. Moreover, subgroup analysis according to pre-eclampsia severity revealed no significant differences in genotype or allele frequencies of the HIF-1α c.1772C>T and c.1790G>A polymorphism in mild pre-eclamptic compared to severe pre-eclamptic group. In addition, there were no significant differences in the frequencies of 3 haplotypes (C-G,-G, T-G, and C-A) between the control and pre-eclamptic groups.

CONCLUSIONS

Our results suggest that the HIF-1α gene polymorphisms are not associated with the development of pre-eclampsia in the studied Korean women population.

Evaluation of Leuconostoc mesenteroides YML003 as a probiotic against low-pathogenic avian influenza (H9N2) virus in chickens

AIM

  The aims of the study were to isolate anti-H9N2 bacteria from Korean Kimchi isolates and to evaluate its performance in cell line, egg and in specific pathogen-free (SPF) chickens.

METHODS AND RESULTS

  Using Madin-Darby canine kidney (MDCK) cell line, 220 bacterial isolates were screened and the isolate YML003 was selected having pronounced antiviral activity against H9N2 virus. This isolate was identified as Leuconostoc mesenteroides by 16S rRNA gene sequencing. Anti-H9N2 activity of the strain was also evaluated by hemagglutination assay. Leuconostoc mesenteroides YML003 was assessed for its survival in gastric juice and 5% bile acid and the antibiotic susceptibility. Both live and heat-killed cells were selected for in vivo chicken feeding experiment. Body weight, immune index, serobiochemical parameters and splenic IFN-γ production were assessed during selected intervals. Viral population in the trachea and cloacae were calculated by quantitative real-time reverse transcriptase PCR (qRT-PCR).

CONCLUSIONS

  Leuconostoc mesenteroides YML003 exhibited anti-H9N2 activity both in in vitro cell line as well as in vivo SPF chickens.

SIGNIFICANCE AND IMPACT OF THE STUDY

  This is a primary report on the anti-H9N2 activity by a Leuconostoc strain. Amid the increasing reports of avian influenza virus occurrence resulting in severe losses to the poultry industry, prophylactic administration of such probiotic strains are highly significant.

Magnetic resonance findings of acute severe lower back pain

Objective

To determine abnormal MRI findings in adults hospitalized with acute severe axial LBP.

Method

Sixty patients with back pain were divided into 3 groups consisting of 1) 23 adults with acute axial severe LBP who could not sit up or stand up for several days, but had not experienced previous back-related diseases or trauma (group A), 2) 19 adults who had been involved in a minor traffic accident, and had mild symptoms but not limited mobility (group B), and 3) 18 adults with LBP with radicular pain (group C)., Various MRI findings were assessed among the above 3 groups and compared as follows: disc herniation (protrusion, extrusion), lumbar disc degeneration (LDD), annular tear, high intensity zone (HIZ), and endplate changes.

Results

The MRI findings of A group were as follows: disc herniation (87%), LDD (100%), annular tear (100%), HIZ (61%), and end plate changes (4.4%). The findings of disc herniation, annular tear, HIZ, and LDD were more prevalent in A group than in B group (p<0.01). HIZ findings were more prevalent in A group than in group B or group C (p<0.05).

Conclusion

Patients with acute severe axial LBP were more likely to have disc herniation, LDD, annular tear, HIZ. Among LBP groups, there was a significant association of HIZ on MRI with acute severe axial LBP.

Clinical Feasibility of Multiplanar Reconstruction Images of Temporal Bone CT in the Diagnosis of Temporal Bone Fracture with Otic-Capsule-Sparing Facial Nerve Paralysis

The aim of this study is to evaluate the feasibility of multiplanar reconstructive (MPR) imaging of temporal bone CT in the diagnosis of temporal bone fracture with oticcapsule-sparing facial nerve paralysis. Twelve patients with traumatic facial nerve paralysis with otic-capsule sparing and temporal bone fractures were selected. Multiplanar reconstruction images were obtained with the V-works 4.0 software program (Cybermed, Seoul, Korea) using axial scanning of high-resolution temporal bone CT of the fracture line. The clinical profiles of the patients displaying temporal bone fractures were examined in relation to the findings. Multiplanar images of the fracture line provided information regarding the direction of the external force that fractured the temporal bone. The fracture line was more continuous in the MPR images than in the axial view. All patients showed an imaginary extended fracture line directed toward the otic capsule. The direction of the fracture line toward the middle ear cavity is important, as it may suggest insult to the otic capsule. The MPR image parallel to the fracture line of the temporal bone provides a guideline for the vector of the force that induced the fracture. Thorough investigation of the critical organs during surgical exploration is recommended if the direction of the fracture in the MPR image points toward the otic capsule in the middle ear even if the fracture line relative to the otic capsule is not well defined in the axial or CT view.

Usefulness of the Scale for the Assessment and Rating of Ataxia (SARA) in Ataxic Stroke Patients

Objective

To examine the usefulness of the Scale for the Assessment and Rating of Ataxia (SARA) in ataxic stroke patients.

Method

This was a retrospective study of 54 patients following their first ataxic stroke. The data used in the analysis comprised ambulation status on admission and scores on the SARA, the Korean version of the Modified Barthel Index (K-MBI) and the Berg Balance Scale (BBS). The subjects were divided into four groups by gait status and into five groups by level of dependency in activities of daily living (ADLs) based on their K-MBI scores. Data were subjected to a ROC curve analysis to obtain cutoff values on the SARA for individual gait status and levels of activity dependency. The correlations between the SARA, K-MBI and BBS scores were also computed.

Results

There was significant correlation between the SARA and the K-MBI scores (p<0.001), and this correlation (r=-0.792) was higher than that found between the BBS and the K-MBI scores (r=0.710). The SARA scores of upper extremity ataxia categories were significantly related to the K-MBI scores of upper extremity related function (p<0.001). The SARA scores were also significantly correlated negatively with ambulation status (p<0.001) and positively with ADL dependency (p<0.001). In the ROC analysis, patients with less than 5.5 points on the SARA had minimal dependency in ADL, while those with more than 23 points showed total dependency.

Conclusion

SARA corresponds well with gait status and ADL dependency in ataxic stroke patients and is considered to be a useful functional measure in that patient group.

Downregulation of mitochondrial lon protease impairs mitochondrial function and causes hepatic insulin resistance in human liver SK-HEP-1 cells

AIMS/HYPOTHESIS

Lon protease degrades oxidatively damaged proteins in mitochondrial matrix. To examine the relationships between mitochondrial quality control, mitochondrial functions and diabetes, we investigated whether lon protease deficiency influences insulin resistance by affecting mitochondrial function.

METHODS

Lon protease-specific small interfering RNA (siRNA) was transfected into human liver SK-HEP-1 cells and changes in molecules related to insulin resistance were analysed.

RESULTS

Reduction in lon protease was achieved using specific siRNA-induced mitochondrial dysfunction in human liver SK-HEP-1 cells. Concurrently, insulin signalling and subsequent insulin action were impaired and levels of gluconeogenic enzymes were increased by lon protein deficiency. Moreover, the activity of mitogen-activated protein kinases and transcription factors related to hepatic gluconeogenesis were elevated in LON (also known as LONP1) siRNA-transfected cells via increased intracellular reactive oxygen species production. Overproduction of lon protease restored mitochondrial function and also diminished the insulin resistance induced by treatment with cholesterol and palmitate. In addition, levels of lon protease decreased dramatically in livers of diabetic db/db mice compared with their lean mice counterparts.

CONCLUSIONS/INTERPRETATION

Here we have demonstrated that reduction of lon protease induced hepatic insulin resistance by lowering mitochondrial function. This is the first study to report that defects in mitochondrial protein quality control could cause insulin resistance and diabetes.